diff options
Diffstat (limited to 'lib/avb')
47 files changed, 8306 insertions, 0 deletions
diff --git a/lib/avb/Makefile b/lib/avb/Makefile new file mode 100644 index 0000000..f5a264a --- /dev/null +++ b/lib/avb/Makefile @@ -0,0 +1,14 @@ +subdir-ccflags-y += -D_FILE_OFFSET_BITS=64 \ + -D_POSIX_C_SOURCE=199309L \ + -Wa,--noexecstack \ + -Werror \ + -Wall \ + -Wextra \ + -Wformat=2 \ + -Wno-psabi \ + -Wno-unused-parameter \ + -ffunction-sections \ + -std=gnu99 +obj-y += libavb/ +obj-y += libavb_ab/ +obj-y += fsl/ diff --git a/lib/avb/fsl/Makefile b/lib/avb/fsl/Makefile new file mode 100644 index 0000000..362c917 --- /dev/null +++ b/lib/avb/fsl/Makefile @@ -0,0 +1,4 @@ +ccflags-$(CONFIG_AVB_DEBUG) += -DAVB_DEBUG +obj-y += fsl_avb.o +obj-y += fsl_avbkey.o +obj-y += fsl_bootctl.o diff --git a/lib/avb/fsl/debug.h b/lib/avb/fsl/debug.h new file mode 100644 index 0000000..c1165ec --- /dev/null +++ b/lib/avb/fsl/debug.h @@ -0,0 +1,35 @@ +/* + * Copyright (C) 2016 Freescale Semiconductor, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __AVB_DEBUG_H__ +#define __AVB_DEBUG_H__ + +#ifdef AVB_VVDEBUG +#define AVB_VDEBUG +#define VVDEBUG(format, ...) printf(" %s: "format, __func__, ##__VA_ARGS__) +#else +#define VVDEBUG(format, ...) +#endif + +#ifdef AVB_VDEBUG +#define AVB_DEBUG +#define VDEBUG(format, ...) printf(" %s: "format, __func__, ##__VA_ARGS__) +#else +#define VDEBUG(format, ...) +#endif + +#ifdef AVB_DEBUG +#define DEBUGAVB(format, ...) printf(" %s: "format, __func__, ##__VA_ARGS__) +#else +#define DEBUGAVB(format, ...) +#endif + +#define ERR(format, ...) printf("%s: "format, __func__, ##__VA_ARGS__) + +#define HEXDUMP_COLS 16 +#define HEXDUMP_WIDTH 1 + +#endif diff --git a/lib/avb/fsl/fsl_avb.c b/lib/avb/fsl/fsl_avb.c new file mode 100644 index 0000000..a1bd160 --- /dev/null +++ b/lib/avb/fsl/fsl_avb.c @@ -0,0 +1,715 @@ +/* + * Copyright (C) 2016 Freescale Semiconductor, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <part.h> +#include <stdlib.h> + +#include <fsl_fastboot.h> +#include <fsl_caam.h> +#include "../../../drivers/usb/gadget/fastboot_lock_unlock.h" + +#include "fsl_avb.h" +#include "fsl_avbkey.h" +#include "debug.h" + +#define FSL_AVB_DEV "mmc" + +#define ALIGN_BYTES 64 /*mmc block read/write need 64 bytes aligned */ + +struct margin_pos { + /* which blk the read/write starts */ + lbaint_t blk_start; + /* which blk the read/write ends */ + lbaint_t blk_end; + /* start position inside the start blk */ + unsigned long start; + /* end position inside the end blk */ + unsigned long end; + /* how many blks can be read/write one time */ + unsigned long multi; +}; +typedef struct margin_pos margin_pos_t; + + +static block_dev_desc_t *fs_dev_desc = NULL; +static block_dev_desc_t *get_mmc_desc(void) { + extern int mmc_get_env_devno(void); + int dev_no = mmc_get_env_devno(); + return get_dev(FSL_AVB_DEV, dev_no); +} + +/* get margin_pos struct from offset [to the partition start/end] and num_bytes to read/write */ +static int32_t get_margin_pos(lbaint_t part_start, lbaint_t part_end, unsigned long blksz, + margin_pos_t *margin, int64_t offset, size_t num_bytes, bool allow_partial) { + long off; + if (offset < 0) { + margin->blk_start = (offset + 1) / blksz + part_end; + margin->start = (off = offset % blksz) == 0 ? 0 : blksz + off; // offset == -1 means the last byte?, or start need -1 + if (offset + num_bytes - 1 >= 0) { + if (!allow_partial) + return -1; + margin->blk_end = part_end; + margin->end = blksz - 1; + } else { + margin->blk_end = (num_bytes + offset) / blksz + part_end; // which blk the last byte is in + margin->end = (off = (num_bytes + offset - 1) % blksz) == 0 ? + 0 : blksz + off; // last byte + } + } else { + margin->blk_start = offset / blksz + part_start; + margin->start = offset % blksz; + margin->blk_end = (offset + num_bytes - 1) / blksz + part_start ; + margin->end = (offset + num_bytes - 1) % blksz; + if (margin->blk_end > part_end) { + if (!allow_partial) + return -1; + margin->blk_end = part_end; + margin->end = blksz - 1; + } + } + VDEBUG("bs=%ld, be=%ld, s=%ld, e=%ld\n", + margin->blk_start, margin->blk_end, margin->start, margin->end); + + if (margin->blk_start > part_end || margin->blk_start < part_start) + return -1; + long multi = margin->blk_end - margin->blk_start - 1 + + (margin->start == 0) + (margin->end == blksz -1); + margin->multi = multi > 0 ? multi : 0; + VDEBUG("bm=%ld\n", margin->multi); + return 0; +} + /* Reads |num_bytes| from offset |offset| from partition with name + * |partition| (NUL-terminated UTF-8 string). If |offset| is + * negative, its absolute value should be interpreted as the number + * of bytes from the end of the partition. + * + * This function returns AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION if + * there is no partition with the given name, + * AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION if the requested + * |offset| is outside the partition, and AVB_IO_RESULT_ERROR_IO if + * there was an I/O error from the underlying I/O subsystem. If the + * operation succeeds as requested AVB_IO_RESULT_OK is returned and + * the data is available in |buffer|. + * + * The only time partial I/O may occur is if reading beyond the end + * of the partition. In this case the value returned in + * |out_num_read| may be smaller than |num_bytes|. + */ + AvbIOResult fsl_read_from_partition(AvbOps* ops, const char* partition, + int64_t offset, size_t num_bytes, + void* buffer, size_t* out_num_read) +{ + struct fastboot_ptentry *pte; + unsigned char *bdata; + unsigned char *out_buf = (unsigned char *)buffer; + unsigned long blksz; + unsigned long s, cnt; + size_t num_read = 0; + lbaint_t part_start, part_end, bs, be; + margin_pos_t margin; + + AvbIOResult ret; + + DEBUGAVB("[%s]: offset=%ld, num_bytes=%zu\n", partition, (long)offset, num_bytes); + + assert(buffer != NULL && out_num_read != NULL); + + if (!fs_dev_desc && (fs_dev_desc = get_mmc_desc()) == NULL) { + ERR("mmc device not found\n"); + return AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION; + } + + pte = fastboot_flash_find_ptn(partition); + if (!pte) { + ERR("no %s partition\n", partition); + return AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION; + } + + blksz = fs_dev_desc->blksz; + part_start = pte->start; + part_end = pte->start + pte->length - 1; + VDEBUG("blksz: %ld, part_end: %ld, part_start: %ld:\n", + blksz, part_end, part_start); + + if(get_margin_pos(part_start, part_end, blksz, + &margin, offset, num_bytes, true)) + return AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION; + + bs = margin.blk_start; + be = margin.blk_end; + s = margin.start; + + // alloc a blksz mem + bdata = (unsigned char *)memalign(ALIGN_BYTES, blksz); + if (bdata == NULL) + return AVB_IO_RESULT_ERROR_OOM; + + // one block a time + while (bs <= be) { + memset(bdata, 0, blksz); + if (!fs_dev_desc->block_read(fs_dev_desc->dev, bs, 1, bdata)) { + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } + cnt = blksz - s; + if (num_read + cnt > num_bytes) + cnt = num_bytes - num_read; + VDEBUG("cur: bs=%ld, start=%ld, cnt=%ld bdata=0x%08x\n", + bs, s, cnt, bdata); + memcpy(out_buf, bdata + s, cnt); + bs++; + num_read += cnt; + out_buf += cnt; + s = 0; + } + *out_num_read = num_read; + ret = AVB_IO_RESULT_OK; +#ifdef AVB_VVDEBUG + printf("\nnum_read=%zu", num_read); + printf("\n----dump---\n"); + print_buffer(0, buffer, HEXDUMP_WIDTH, num_read, 0); + printf("--- end ---\n"); +#endif + +fail: + free(bdata); + return ret; +} + +/* multi block read version of read_from_partition */ + AvbIOResult fsl_read_from_partition_multi(AvbOps* ops, const char* partition, + int64_t offset, size_t num_bytes, + void* buffer, size_t* out_num_read) +{ + struct fastboot_ptentry *pte; + unsigned char *bdata; + unsigned char *out_buf = (unsigned char *)buffer; + unsigned char *dst, *dst64 = NULL; + unsigned long blksz; + unsigned long s, cnt; + size_t num_read = 0; + lbaint_t part_start, part_end, bs, be, bm, blk_num; + margin_pos_t margin; + + AvbIOResult ret; + + DEBUGAVB("[%s]: offset=%ld, num_bytes=%zu\n", partition, (long)offset, num_bytes); + + assert(buffer != NULL && out_num_read != NULL); + + if (!fs_dev_desc && (fs_dev_desc = get_mmc_desc()) == NULL) { + ERR("mmc device not found\n"); + return AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION; + } + + pte = fastboot_flash_find_ptn(partition); + if (!pte) { + ERR("no %s partition\n", partition); + return AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION; + } + + blksz = fs_dev_desc->blksz; + part_start = pte->start; + part_end = pte->start + pte->length - 1; + VDEBUG("blksz: %ld, part_end: %ld, part_start: %ld:\n", + blksz, part_end, part_start); + + if(get_margin_pos(part_start, part_end, blksz, + &margin, offset, num_bytes, true)) + return AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION; + + bs = margin.blk_start; + be = margin.blk_end; + s = margin.start; + bm = margin.multi; + + // alloc a blksz mem + bdata = (unsigned char *)memalign(ALIGN_BYTES, blksz); + if (bdata == NULL) + return AVB_IO_RESULT_ERROR_OOM; + + // support multi blk read + while (bs <= be) { + if (!s && bm > 1) { + dst = out_buf; + dst64 = PTR_ALIGN(out_buf, 64); //for mmc blk read alignment + VDEBUG("cur: dst=0x%08x, dst64=0x%08x\n", dst, dst64); + if (dst64 != dst) { + dst = dst64; + bm--; + } + blk_num = bm; + cnt = bm * blksz; + bm = 0; //no more multi blk + } else { + blk_num = 1; + cnt = blksz - s; + if (num_read + cnt > num_bytes) + cnt = num_bytes - num_read; + dst = bdata; + } + VDEBUG("cur: bs=%ld, num=%ld, start=%ld, cnt=%ld dst=0x%08x\n", + bs, blk_num, s, cnt, dst); + if (!fs_dev_desc->block_read(fs_dev_desc->dev, bs, blk_num, dst)) { + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } + + if (dst == bdata) + memcpy(out_buf, bdata + s, cnt); + else if (dst == dst64) + memcpy(out_buf, dst, cnt); //internal copy + + s = 0; + bs += blk_num; + num_read += cnt; + out_buf += cnt; +#ifdef AVB_VVDEBUG + printf("\nnum_read=%ld", cnt); + printf("\n----dump---\n"); + print_buffer(0, buffer, HEXDUMP_WIDTH, cnt, 0); + printf("--- end ---\n"); +#endif + } + *out_num_read = num_read; + ret = AVB_IO_RESULT_OK; +#ifdef AVB_VVDEBUG + printf("\nnum_read=%zu", num_read); + printf("\n----dump---\n"); + print_buffer(0, buffer, HEXDUMP_WIDTH, num_read, 0); + printf("--- end ---\n"); +#endif + +fail: + free(bdata); + return ret; +} + + /* Writes |num_bytes| from |bffer| at offset |offset| to partition + * with name |partition| (NUL-terminated UTF-8 string). If |offset| + * is negative, its absolute value should be interpreted as the + * number of bytes from the end of the partition. + * + * This function returns AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION if + * there is no partition with the given name, + * AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION if the requested + * byterange goes outside the partition, and AVB_IO_RESULT_ERROR_IO + * if there was an I/O error from the underlying I/O subsystem. If + * the operation succeeds as requested AVB_IO_RESULT_OK is + * returned. + * + * This function never does any partial I/O, it either transfers all + * of the requested bytes or returns an error. + */ + AvbIOResult fsl_write_to_partition(AvbOps* ops, const char* partition, + int64_t offset, size_t num_bytes, + const void* buffer) +{ + struct fastboot_ptentry *pte; + unsigned char *bdata; + unsigned char *in_buf = (unsigned char *)buffer; + unsigned long blksz; + unsigned long s, cnt; + size_t num_write = 0; + lbaint_t part_start, part_end, bs; + margin_pos_t margin; + + AvbIOResult ret; + + DEBUGAVB("[%s]: offset=%ld, num_bytes=%zu\n", partition, (long)offset, num_bytes); + + assert(buffer != NULL); + + if (!fs_dev_desc && (fs_dev_desc = get_mmc_desc()) == NULL) { + ERR("mmc device not found\n"); + return AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION; + } + + pte = fastboot_flash_find_ptn(partition); + if (!pte) { + ERR("no %s partition\n", partition); + return AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION; + } + + blksz = fs_dev_desc->blksz; + part_start = pte->start; + part_end = pte->start + pte->length - 1; + VDEBUG("blksz: %ld, part_end: %ld, part_start: %ld:\n", + blksz, part_end, part_start); + + if(get_margin_pos(part_start, part_end, blksz, + &margin, offset, num_bytes, false)) + return AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION; + + bs = margin.blk_start; + s = margin.start; + + // alloc a blksz mem + bdata = (unsigned char *)memalign(ALIGN_BYTES, blksz); + if (bdata == NULL) + return AVB_IO_RESULT_ERROR_OOM; + + while (num_write < num_bytes) { + memset(bdata, 0, blksz); + cnt = blksz - s; + if (num_write + cnt > num_bytes) + cnt = num_bytes - num_write; + if (!s || cnt != blksz) { //read blk first + if (!fs_dev_desc->block_read(fs_dev_desc->dev, bs, 1, bdata)) { + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } + } + memcpy(bdata + s, in_buf, cnt); //change data + VDEBUG("cur: bs=%ld, start=%ld, cnt=%ld bdata=0x%08x\n", + bs, s, cnt, bdata); + if (!fs_dev_desc->block_write(fs_dev_desc->dev, bs, 1, bdata)) { + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } + bs++; + num_write += cnt; + in_buf += cnt; + if (s != 0) + s = 0; + } + ret = AVB_IO_RESULT_OK; + +fail: + free(bdata); + return ret; +} + +/* Reads A/B metadata from persistent storage. Returned data is + * properly byteswapped. Returns AVB_IO_RESULT_OK on success, error + * code otherwise. + * + * If the data read is invalid (e.g. wrong magic or CRC checksum + * failure), the metadata shoule be reset using avb_ab_data_init() + * and then written to persistent storage. + * + * Implementations will typically want to use avb_ab_data_read() + * here to use the 'misc' partition for persistent storage. + */ +AvbIOResult fsl_read_ab_metadata(AvbABOps* ab_ops, struct AvbABData* data) +{ + return avb_ab_data_read(ab_ops, data); +} + +/* Writes A/B metadata to persistent storage. This will byteswap and + * update the CRC as needed. Returns AVB_IO_RESULT_OK on success, + * error code otherwise. + * + * Implementations will typically want to use avb_ab_data_write() + * here to use the 'misc' partition for persistent storage. + */ +AvbIOResult fsl_write_ab_metadata(AvbABOps* ab_ops, const struct AvbABData* data) +{ + return avb_ab_data_write(ab_ops, data); +} + +/* Checks if the given public key used to sign the 'vbmeta' + * partition is trusted. Boot loaders typically compare this with + * embedded key material generated with 'avbtool + * extract_public_key'. + * + * If AVB_IO_RESULT_OK is returned then |out_is_trusted| is set - + * true if trusted or false if untrusted. + */ +AvbIOResult fsl_validate_vbmeta_public_key(AvbOps* ops, + const uint8_t* public_key_data, + size_t public_key_length, + bool* out_is_trusted) { + kblb_hdr_t hdr; + kblb_tag_t *pubk; + size_t num_read, blob_size; + uint8_t *extract_key = NULL; + uint8_t *read_keyblb = NULL; + AvbIOResult ret; + + assert(ops != NULL && out_is_trusted != NULL); + *out_is_trusted = false; + /* read the kblb header */ + if (ops->read_from_partition(ops, "avbkey", 0, sizeof(hdr), + (void *)&hdr, &num_read) != AVB_IO_RESULT_OK) { + ERR("read partition avbkey error\n"); + return AVB_IO_RESULT_ERROR_IO; + } + + if (num_read != sizeof(hdr) || + memcmp(hdr.magic, AVB_KBLB_MAGIC, AVB_KBLB_MAGIC_LEN) != 0) { + ERR("avbkey partition magic not match\n"); + return AVB_IO_RESULT_ERROR_IO; + } + + pubk = &hdr.pubk_tag; + if (pubk->len != public_key_length){ + ERR("avbkey len not match\n"); + return AVB_IO_RESULT_ERROR_IO; + } + blob_size = pubk->len + AVB_CAAM_PAD; + extract_key = malloc(pubk->len); + read_keyblb = malloc(blob_size); + if (extract_key == NULL || read_keyblb == NULL) { + ret = AVB_IO_RESULT_ERROR_OOM; + goto fail; + } + + /* read public keyblob */ + if (ops->read_from_partition(ops, "avbkey", pubk->offset, blob_size, + (void *)read_keyblb, &num_read) != AVB_IO_RESULT_OK) { + ERR("read public keyblob error\n"); + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } + if (num_read != blob_size) { + ERR("avbkey partition magic not match\n"); + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } + + /* caam decrypt */ + caam_open(); + if (caam_decap_blob((uint32_t)extract_key, (uint32_t)read_keyblb, pubk->len)) { + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } + /* match given public key */ + if (memcmp(extract_key, public_key_data, public_key_length)) { + ret = AVB_IO_RESULT_OK; + goto fail; + } +#ifdef AVB_VDEBUG + printf("\n----key dump: stored---\n"); + print_buffer(0, extract_key, HEXDUMP_WIDTH, pubk->len, 0); + printf("\n----key dump: vbmeta---\n"); + print_buffer(0, public_key_data, HEXDUMP_WIDTH, public_key_length, 0); + printf("--- end ---\n"); +#endif + + *out_is_trusted = true; + ret = AVB_IO_RESULT_OK; +fail: + if (extract_key != NULL) + free(extract_key); + if (read_keyblb != NULL) + free(read_keyblb); + return ret; +} + +/* Gets the rollback index corresponding to the slot given by + * |rollback_index_slot|. The value is returned in + * |out_rollback_index|. Returns AVB_IO_RESULT_OK if the rollback + * index was retrieved, otherwise an error code. + * + * A device may have a limited amount of rollback index slots (say, + * one or four) so may error out if |rollback_index_slot| exceeds + * this number. + */ +AvbIOResult fsl_read_rollback_index(AvbOps* ops, size_t rollback_index_slot, + uint64_t* out_rollback_index) { + kblb_hdr_t hdr; + kblb_tag_t *rbk; + size_t num_read, blob_size; + uint64_t *extract_idx = NULL; + uint64_t *read_keyblb = NULL; + AvbIOResult ret; + + assert(ops != NULL && out_rollback_index != NULL); + *out_rollback_index = ~0; + + DEBUGAVB("read rollback slot: %zu\n", rollback_index_slot); + + if (rollback_index_slot >= AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_SLOTS) + return AVB_IO_RESULT_ERROR_IO; + + /* read the kblb header */ + if (ops->read_from_partition(ops, "avbkey", 0, sizeof(hdr), + (void *)&hdr, &num_read) != AVB_IO_RESULT_OK) { + ERR("read partition avbkey error\n"); + return AVB_IO_RESULT_ERROR_IO; + } + + if (num_read != sizeof(hdr) || + memcmp(hdr.magic, AVB_KBLB_MAGIC, AVB_KBLB_MAGIC_LEN) != 0) { + ERR("avbkey partition magic not match\n"); + return AVB_IO_RESULT_ERROR_IO; + } + + rbk = &hdr.rbk_tags[rollback_index_slot]; + blob_size = rbk->len + AVB_CAAM_PAD; + extract_idx = malloc(rbk->len); + read_keyblb = malloc(blob_size); + if (extract_idx == NULL || read_keyblb == NULL) { + ret = AVB_IO_RESULT_ERROR_OOM; + goto fail; + } + + /* read rollback_index keyblob */ + if (ops->read_from_partition(ops, "avbkey", rbk->offset, blob_size, + (void *)read_keyblb, &num_read) != AVB_IO_RESULT_OK) { + ERR("read public keyblob error\n"); + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } + if (num_read != blob_size) { + ERR("avbkey read len not match\n"); + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } + + /* caam decrypt */ + caam_open(); + if (caam_decap_blob((uint32_t)extract_idx, (uint32_t)read_keyblb, rbk->len)) { + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } +#ifdef AVB_VVDEBUG + printf("\n----idx dump: ---\n"); + print_buffer(0, extract_idx, HEXDUMP_WIDTH, rbk->len, 0); + printf("--- end ---\n"); +#endif + + *out_rollback_index = *extract_idx; + DEBUGAVB("rollback_index = %" PRIu64 "\n", *out_rollback_index); + ret = AVB_IO_RESULT_OK; +fail: + if (extract_idx != NULL) + free(extract_idx); + if (read_keyblb != NULL) + free(read_keyblb); + return ret; +} + +/* Sets the rollback index corresponding to the slot given by + * |rollback_index_slot| to |rollback_index|. Returns + * AVB_IO_RESULT_OK if the rollback index was set, otherwise an + * error code. + * + * A device may have a limited amount of rollback index slots (say, + * one or four) so may error out if |rollback_index_slot| exceeds + * this number. + */ +AvbIOResult fsl_write_rollback_index(AvbOps* ops, size_t rollback_index_slot, + uint64_t rollback_index) { + kblb_hdr_t hdr; + kblb_tag_t *rbk; + size_t num_read, blob_size; + uint64_t *plain_idx = NULL; + uint64_t *write_keyblb = NULL; + AvbIOResult ret; + + DEBUGAVB("write to rollback slot: (%zu, %" PRIu64 ")\n", + rollback_index_slot, rollback_index); + + assert(ops != NULL); + + if (rollback_index_slot >= AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_SLOTS) + return AVB_IO_RESULT_ERROR_IO; + + /* read the kblb header */ + if (ops->read_from_partition(ops, "avbkey", 0, sizeof(hdr), + (void *)&hdr, &num_read) != AVB_IO_RESULT_OK) { + ERR("read partition avbkey error\n"); + return AVB_IO_RESULT_ERROR_IO; + } + + if (num_read != sizeof(hdr) || + memcmp(hdr.magic, AVB_KBLB_MAGIC, AVB_KBLB_MAGIC_LEN) != 0) { + ERR("avbkey partition magic not match\n"); + return AVB_IO_RESULT_ERROR_IO; + } + + rbk = &hdr.rbk_tags[rollback_index_slot]; + blob_size = rbk->len + AVB_CAAM_PAD; + plain_idx = malloc(rbk->len); + write_keyblb = malloc(blob_size); + if (plain_idx == NULL || write_keyblb == NULL) { + ret = AVB_IO_RESULT_ERROR_OOM; + goto fail; + } + memset(plain_idx, 0, rbk->len); + *plain_idx = rollback_index; + + /* caam encrypt */ + caam_open(); + if (caam_gen_blob((uint32_t)plain_idx, (uint32_t)write_keyblb, rbk->len)) { + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } + + /* write rollback_index keyblob */ + if (ops->write_to_partition(ops, "avbkey", rbk->offset, blob_size, + (void *)write_keyblb) != AVB_IO_RESULT_OK) { + ERR("read public keyblob error\n"); + ret = AVB_IO_RESULT_ERROR_IO; + goto fail; + } + ret = AVB_IO_RESULT_OK; +fail: + if (plain_idx != NULL) + free(plain_idx); + if (write_keyblb != NULL) + free(write_keyblb); + return ret; +} + +/* Gets whether the device is unlocked. The value is returned in + * |out_is_unlocked| (true if unlocked, false otherwise). Returns + * AVB_IO_RESULT_OK if the state was retrieved, otherwise an error + * code. + */ +AvbIOResult fsl_read_is_device_unlocked(AvbOps* ops, bool* out_is_unlocked) { + + FbLockState status; + + assert(out_is_unlocked != NULL); + *out_is_unlocked = false; + + status = fastboot_get_lock_stat(); + if (status != FASTBOOT_LOCK_ERROR) { + if (status == FASTBOOT_LOCK) + *out_is_unlocked = false; + else + *out_is_unlocked = true; + } else + return AVB_IO_RESULT_ERROR_IO; + + DEBUGAVB("is_unlocked=%d\n", *out_is_unlocked); + return AVB_IO_RESULT_OK; +} + +/* Gets the unique partition GUID for a partition with name in + * |partition| (NUL-terminated UTF-8 string). The GUID is copied as + * a string into |guid_buf| of size |guid_buf_size| and will be NUL + * terminated. The string must be lower-case and properly + * hyphenated. For example: + * + * 527c1c6d-6361-4593-8842-3c78fcd39219 + * + * Returns AVB_IO_RESULT_OK on success, otherwise an error code. + */ +AvbIOResult fsl_get_unique_guid_for_partition(AvbOps* ops, + const char* partition, + char* guid_buf, + size_t guid_buf_size) { + assert(guid_buf != NULL); +#ifdef CONFIG_PARTITION_UUIDS + struct fastboot_ptentry *pte; + pte = fastboot_flash_find_ptn(partition); + if (!pte) { + ERR("no %s partition\n", partition); + return AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION; + } + strncpy(guid_buf, (const char *)pte->uuid, guid_buf_size); + guid_buf[guid_buf_size - 1] = '\0'; + DEBUGAVB("[%s]: GUID=%s\n", partition, guid_buf); + return AVB_IO_RESULT_OK; +#else + return AVB_IO_RESULT_ERROR_IO; +#endif +} diff --git a/lib/avb/fsl/fsl_avb.h b/lib/avb/fsl/fsl_avb.h new file mode 100644 index 0000000..2230931 --- /dev/null +++ b/lib/avb/fsl/fsl_avb.h @@ -0,0 +1,174 @@ +/* + * Copyright (C) 2016 Freescale Semiconductor, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __FSL_AVB_H__ +#define __FSL_AVB_H__ + +#include <libavb_ab.h> +/* Reads |num_bytes| from offset |offset| from partition with name + * |partition| (NUL-terminated UTF-8 string). If |offset| is + * negative, its absolute value should be interpreted as the number + * of bytes from the end of the partition. + * + * This function returns AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION if + * there is no partition with the given name, + * AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION if the requested + * |offset| is outside the partition, and AVB_IO_RESULT_ERROR_IO if + * there was an I/O error from the underlying I/O subsystem. If the + * operation succeeds as requested AVB_IO_RESULT_OK is returned and + * the data is available in |buffer|. + * + * The only time partial I/O may occur is if reading beyond the end + * of the partition. In this case the value returned in + * |out_num_read| may be smaller than |num_bytes|. + */ +AvbIOResult fsl_read_from_partition(AvbOps* ops, const char* partition, + int64_t offset, size_t num_bytes, + void* buffer, size_t* out_num_read); + +/* multi block read version + * */ +AvbIOResult fsl_read_from_partition_multi(AvbOps* ops, const char* partition, + int64_t offset, size_t num_bytes, + void* buffer, size_t* out_num_read); + +/* Writes |num_bytes| from |bffer| at offset |offset| to partition + * with name |partition| (NUL-terminated UTF-8 string). If |offset| + * is negative, its absolute value should be interpreted as the + * number of bytes from the end of the partition. + * + * This function returns AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION if + * there is no partition with the given name, + * AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION if the requested + * byterange goes outside the partition, and AVB_IO_RESULT_ERROR_IO + * if there was an I/O error from the underlying I/O subsystem. If + * the operation succeeds as requested AVB_IO_RESULT_OK is + * returned. + * + * This function never does any partial I/O, it either transfers all + * of the requested bytes or returns an error. + */ +AvbIOResult fsl_write_to_partition(AvbOps* ops, const char* partition, + int64_t offset, size_t num_bytes, + const void* buffer); + +/* Reads A/B metadata from persistent storage. Returned data is + * properly byteswapped. Returns AVB_IO_RESULT_OK on success, error + * code otherwise. + * + * If the data read is invalid (e.g. wrong magic or CRC checksum + * failure), the metadata shoule be reset using avb_ab_data_init() + * and then written to persistent storage. + * + * Implementations will typically want to use avb_ab_data_read() + * here to use the 'misc' partition for persistent storage. + */ +AvbIOResult fsl_read_ab_metadata(AvbABOps* ab_ops, struct AvbABData* data); + +/* Writes A/B metadata to persistent storage. This will byteswap and + * update the CRC as needed. Returns AVB_IO_RESULT_OK on success, + * error code otherwise. + * + * Implementations will typically want to use avb_ab_data_write() + * here to use the 'misc' partition for persistent storage. + */ +AvbIOResult fsl_write_ab_metadata(AvbABOps* ab_ops, const struct AvbABData* data); + +/* Checks if the given public key used to sign the 'vbmeta' + * partition is trusted. Boot loaders typically compare this with + * embedded key material generated with 'avbtool + * extract_public_key'. + * + * If AVB_IO_RESULT_OK is returned then |out_is_trusted| is set - + * true if trusted or false if untrusted. + */ +AvbIOResult fsl_validate_vbmeta_public_key(AvbOps* ops, + const uint8_t* public_key_data, + size_t public_key_length, + bool* out_is_trusted); + +/* Gets the rollback index corresponding to the slot given by + * |rollback_index_slot|. The value is returned in + * |out_rollback_index|. Returns AVB_IO_RESULT_OK if the rollback + * index was retrieved, otherwise an error code. + * + * A device may have a limited amount of rollback index slots (say, + * one or four) so may error out if |rollback_index_slot| exceeds + * this number. + */ +AvbIOResult fsl_read_rollback_index(AvbOps* ops, size_t rollback_index_slot, + uint64_t* out_rollback_index); + +/* Sets the rollback index corresponding to the slot given by + * |rollback_index_slot| to |rollback_index|. Returns + * AVB_IO_RESULT_OK if the rollback index was set, otherwise an + * error code. + * + * A device may have a limited amount of rollback index slots (say, + * one or four) so may error out if |rollback_index_slot| exceeds + * this number. + */ +AvbIOResult fsl_write_rollback_index(AvbOps* ops, size_t rollback_index_slot, + uint64_t rollback_index); + +/* Gets whether the device is unlocked. The value is returned in + * |out_is_unlocked| (true if unlocked, false otherwise). Returns + * AVB_IO_RESULT_OK if the state was retrieved, otherwise an error + * code. + */ +AvbIOResult fsl_read_is_device_unlocked(AvbOps* ops, bool* out_is_unlocked); + +/* Gets the unique partition GUID for a partition with name in + * |partition| (NUL-terminated UTF-8 string). The GUID is copied as + * a string into |guid_buf| of size |guid_buf_size| and will be NUL + * terminated. The string must be lower-case and properly + * hyphenated. For example: + * + * 527c1c6d-6361-4593-8842-3c78fcd39219 + * + * Returns AVB_IO_RESULT_OK on success, otherwise an error code. + */ +AvbIOResult fsl_get_unique_guid_for_partition(AvbOps* ops, + const char* partition, + char* guid_buf, + size_t guid_buf_size); + +/* check if the fastboot getvar cmd is for query [avb] bootctl's slot var + * cmd is the fastboot getvar's cmd in + * return true if it is a bootctl related cmd, false if it's not. + * */ +bool is_slotvar_avb(char *cmd); + +/* return 0 for the first slot + * return 1 for the second slot + * return -1 for not supported slot + * */ +int slotidx_from_suffix(char *suffix); + +/* return fastboot's getvar cmd response + * cmd is the fastboot getvar's cmd in + * if return 0, buffer is bootctl's slot var out + * if return -1, buffer is error string + * */ +int get_slotvar_avb(AvbABOps *ab_ops, char *cmd, char *buffer, size_t size); + +/* reset rollback_index part in avbkey partition + * used in the switch from LOCK to UNLOCK + * return 0 if success, non 0 if fail. + * */ +int rbkidx_erase(const char * kblb_part); + +/* init the avbkey partition, include the header/public key/rollback index + * for public key/rollback index part, use caam to do encrypt + * return 0 if success, non 0 if fail. + * */ +int avbkeyblb_init(uint8_t *plainkey, uint32_t keylen, const char *kblb_part /*"avbkey"*/); + +/* read a/b metadata to get curr slot + * return slot suffix '_a'/'_b' or NULL */ +char *select_slot(AvbABOps *ab_ops); + +#endif /* __FSL_AVB_H__ */ diff --git a/lib/avb/fsl/fsl_avbkey.c b/lib/avb/fsl/fsl_avbkey.c new file mode 100644 index 0000000..db0f068 --- /dev/null +++ b/lib/avb/fsl/fsl_avbkey.c @@ -0,0 +1,184 @@ +/* + * Copyright (C) 2016 Freescale Semiconductor, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <stdlib.h> +#include <fsl_caam.h> +#include <fuse.h> + +#include "fsl_avb.h" +#include "fsl_avbkey.h" +#include "debug.h" + +/* bank 15, GP7, 0xc80[31:0] */ +#define AVBKEY_FUSE_BANK 15 +#define AVBKEY_FUSE_WORD 0 +#define AVBKEY_FUSE_MASK 0xffffffff +#define AVBKEY_FUSE_INIT 0x4156424b /* 'avbk' */ + + +static int encrypt_write(uint8_t *plain, uint32_t len, const char * part, size_t offset) { + + uint8_t *blb; + uint32_t blbsize; + int ret; + + blbsize = len + AVB_CAAM_PAD; + blb = (uint8_t *)malloc(blbsize); + if (blb == NULL) + return -1; + + caam_open(); + if (caam_gen_blob((uint32_t)plain, (uint32_t)blb, len)) { + ret = -1; + goto fail; + } + + if (fsl_write_to_partition(NULL, part, offset, blbsize, + (void *)blb) != AVB_IO_RESULT_OK) { + ret = -1; + goto fail; + } + ret = 0; + +fail: + free(blb); + return ret; +} + +int rbkidx_erase(const char * kblb_part) { + int i; + size_t num_read; + kblb_hdr_t hdr; + kblb_tag_t *tag; + /* read the kblb header */ + if (fsl_read_from_partition(NULL, kblb_part, 0, sizeof(hdr), + (void *)&hdr, &num_read) != AVB_IO_RESULT_OK) { + ERR("read partition avbkey error\n"); + return -1; + } + if (num_read != sizeof(hdr) || + memcmp(hdr.magic, AVB_KBLB_MAGIC, AVB_KBLB_MAGIC_LEN) != 0) { + ERR("avbkey partition magic not match\n"); + return -1; + } + /* reset rollback index */ + uint32_t offset = AVB_RBIDX_START; + uint32_t rbidx_len = AVB_RBIDX_LEN; + uint8_t *rbidx = malloc(rbidx_len); + if (rbidx == NULL) + return -1; + memset(rbidx, 0, rbidx_len); + *(uint64_t *)rbidx = AVB_RBIDX_INITVAL; + for (i = 0; i < AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_SLOTS; i++) { + tag = &hdr.rbk_tags[i]; + tag->flag = AVB_RBIDX_FLAG; + tag->offset = offset; + tag->len = rbidx_len; + /* caam encrypt and write */ + if (encrypt_write(rbidx, tag->len, kblb_part, tag->offset) != 0) { + ERR("write rollback index keyblob error\n"); + free(rbidx); + return -1; + } + offset += AVB_RBIDX_ALIGN; + } + free(rbidx); + /* write hdr */ + if (fsl_write_to_partition(NULL, kblb_part, 0, + sizeof(hdr), (void *)&hdr) != AVB_IO_RESULT_OK) { + ERR("write avbkey hdr error\n"); + return -1; + } + return 0; +} + +int avbkeyblb_init(uint8_t *plainkey, uint32_t keylen, const char * kblb_part) { + int i; + kblb_hdr_t hdr; + kblb_tag_t *tag; + uint32_t fuse_val; + + /* read fuse to check enable init */ + /* fuse_read read the shadow reg of fuse + * use fuse_sense to real read fuse */ +#ifdef CONFIG_AVB_FUSE + if (fuse_sense(AVBKEY_FUSE_BANK, AVBKEY_FUSE_WORD, &fuse_val)) { +#else + if (fuse_read(AVBKEY_FUSE_BANK, AVBKEY_FUSE_WORD, &fuse_val)) { +#endif + ERR("read fuse error\n"); + return -1; + } + if ((fuse_val & AVBKEY_FUSE_MASK) == AVBKEY_FUSE_INIT) { + ERR("key already init\n"); + return -1; + } + fuse_val = AVBKEY_FUSE_MASK & AVBKEY_FUSE_INIT; + + /* write fuse to prevent init again */ + /* fuse_override write the shadow reg of fuse + * use fuse_prog to PERMANENT write fuse */ +#ifdef CONFIG_AVB_FUSE + if (fuse_prog(AVBKEY_FUSE_BANK, AVBKEY_FUSE_WORD, fuse_val)) { +#else + if (fuse_override(AVBKEY_FUSE_BANK, AVBKEY_FUSE_WORD, fuse_val)) { +#endif + ERR("write fuse error\n"); + return -1; + } + + assert(plainkey != NULL); + + /* check overflow */ + if (keylen > AVB_RBIDX_START - AVB_PUBKY_OFFSET) { + ERR("key len overflow\n"); + return -1; + } + + /* init pubkey */ + tag = &hdr.pubk_tag; + tag->flag = AVB_PUBKY_FLAG; + tag->offset = AVB_PUBKY_OFFSET; + tag->len = keylen; + /* caam encrypt and write */ + if (encrypt_write(plainkey, tag->len, kblb_part, tag->offset) != 0) { + ERR("write pubkey keyblob error\n"); + return -1; + } + + /* init rollback index */ + uint32_t offset = AVB_RBIDX_START; + uint32_t rbidx_len = AVB_RBIDX_LEN; + uint8_t *rbidx = malloc(rbidx_len); + if (rbidx == NULL) + return -1; + memset(rbidx, 0, rbidx_len); + *(uint64_t *)rbidx = AVB_RBIDX_INITVAL; + for (i = 0; i < AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_SLOTS; i++) { + tag = &hdr.rbk_tags[i]; + tag->flag = AVB_RBIDX_FLAG; + tag->offset = offset; + tag->len = rbidx_len; + /* caam encrypt and write */ + if (encrypt_write(rbidx, tag->len, kblb_part, tag->offset) != 0) { + ERR("write rollback index keyblob error\n"); + free(rbidx); + return -1; + } + offset += AVB_RBIDX_ALIGN; + } + free(rbidx); + + /* init hdr */ + memcpy(hdr.magic, AVB_KBLB_MAGIC, AVB_KBLB_MAGIC_LEN); + if (fsl_write_to_partition(NULL, kblb_part, 0, + sizeof(hdr), (void *)&hdr) != AVB_IO_RESULT_OK) { + ERR("write avbkey hdr error\n"); + return -1; + } + return 0; +} diff --git a/lib/avb/fsl/fsl_avbkey.h b/lib/avb/fsl/fsl_avbkey.h new file mode 100644 index 0000000..988158f --- /dev/null +++ b/lib/avb/fsl/fsl_avbkey.h @@ -0,0 +1,44 @@ +/* + * Copyright (C) 2016 Freescale Semiconductor, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __FSL_AVBKEY_H__ +#define __FSL_AVBKEY_H__ + + +#define AVB_CAAM_PAD 48 + +#define AVB_PUBKY_FLAG 0xABAB +#define AVB_PUBKY_OFFSET 0x1000 + +#define AVB_RBIDX_FLAG 0xCDCD +#define AVB_RBIDX_START 0x2000 +#define AVB_RBIDX_ALIGN 0x1000 +#define AVB_RBIDX_LEN 0x1D0 +#define AVB_RBIDX_INITVAL 0 + + +#define AVB_KBLB_MAGIC "\0KBLB!" +#define AVB_KBLB_MAGIC_LEN 6 + + +struct kblb_tag { + uint32_t flag; + uint32_t offset; + uint32_t len; +}; +typedef struct kblb_tag kblb_tag_t; + +struct kblb_hdr { + /* avbkey partition magic */ + char magic[AVB_KBLB_MAGIC_LEN]; + /* public key keyblb tag */ + kblb_tag_t pubk_tag; + /* rollback index keyblb tag */ + kblb_tag_t rbk_tags[AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_SLOTS]; +}; +typedef struct kblb_hdr kblb_hdr_t; + +#endif diff --git a/lib/avb/fsl/fsl_bootctl.c b/lib/avb/fsl/fsl_bootctl.c new file mode 100644 index 0000000..94392cf --- /dev/null +++ b/lib/avb/fsl/fsl_bootctl.c @@ -0,0 +1,176 @@ +/* + * Copyright (C) 2016 Freescale Semiconductor, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <stdlib.h> +#include <linux/string.h> + +#include "fsl_avb.h" + +/* as libavb's bootctl doesn't have the get_var support + * we add the getvar support on our side ...*/ +#define SLOT_NUM 2 +static char *slot_suffix[SLOT_NUM] = {"_a", "_b"}; + +static int strcmp_l1(const char *s1, const char *s2) { + if (!s1 || !s2) + return -1; + return strncmp(s1, s2, strlen(s1)); +} + +static bool slot_is_bootable(AvbABSlotData* slot) { + return slot->priority > 0 && + (slot->successful_boot || (slot->tries_remaining > 0)); +} + +int slotidx_from_suffix(char *suffix) { + int slot = -1; + + if (!strcmp(suffix, "_a") || + !strcmp(suffix, "a")) + slot = 0; + else if (!strcmp(suffix, "_b") || + !strcmp(suffix, "b")) + slot = 1; + + return slot; +} + +bool is_slotvar_avb(char *cmd) { + + assert(cmd != NULL); + if (!strcmp_l1("has-slot:", cmd) || + !strcmp_l1("slot-successful:", cmd) || + !strcmp_l1("slot-count", cmd) || + !strcmp_l1("slot-suffixes", cmd) || + !strcmp_l1("current-slot", cmd) || + !strcmp_l1("slot-unbootable:", cmd) || + !strcmp_l1("slot-retry-count:", cmd)) + return true; + return false; +} + +static int get_curr_slot(AvbABData *ab_data) { + if (slot_is_bootable(&ab_data->slots[0]) && + slot_is_bootable(&ab_data->slots[1])) { + if (ab_data->slots[1].priority > ab_data->slots[0].priority) + return 1; + else + return 0; + } else if (slot_is_bootable(&ab_data->slots[0])) + return 0; + else if (slot_is_bootable(&ab_data->slots[1])) + return 1; + else + return -1; +} + +int get_slotvar_avb(AvbABOps *ab_ops, char *cmd, char *buffer, size_t size) { + + AvbABData ab_data; + AvbABSlotData *slot_data; + int slot; + + assert(ab_ops != NULL && cmd != NULL && buffer != NULL); + + char *str = cmd; + if (!strcmp_l1("has-slot:", cmd)) { + str += strlen("has-slot:"); + if (!strcmp(str, "system") || !strcmp(str, "boot")) + strlcpy(buffer, "yes", size); + else + strlcpy(buffer, "no", size); + return 0; + + } else if (!strcmp_l1("slot-suffixes", cmd)) { + strlcpy(buffer, "_a,_b", size); + return 0 ; + + } else if (!strcmp_l1("slot-count", cmd)) { + strlcpy(buffer, "2", size); + return 0 ; + } + + /* load ab meta */ + if (ab_ops->read_ab_metadata == NULL || + ab_ops->read_ab_metadata(ab_ops, &ab_data) != AVB_IO_RESULT_OK) { + strlcpy(buffer, "ab data read error", size); + return -1 ; + } + + if (!strcmp_l1("current-slot", cmd)) { + int curr = get_curr_slot(&ab_data); + if (curr >= 0 && curr < SLOT_NUM) + strlcpy(buffer, slot_suffix[curr], size); + else { + strlcpy(buffer, "no bootable slot", size); + return -1; + } + + } else if (!strcmp_l1("slot-successful:", cmd)) { + str += strlen("slot-successful:"); + slot = slotidx_from_suffix(str); + if (slot < 0) { + strlcpy(buffer, "no such slot", size); + return -1; + } else { + slot_data = &ab_data.slots[slot]; + bool succ = (slot_data->successful_boot != 0); + strlcpy(buffer, succ ? "yes" : "no", size); + } + + } else if (!strcmp_l1("slot-unbootable:", cmd)) { + str += strlen("slot-unbootable:"); + slot = slotidx_from_suffix(str); + if (slot < 0) { + strlcpy(buffer, "no such slot", size); + return -1; + } else { + slot_data = &ab_data.slots[slot]; + bool bootable = slot_is_bootable(slot_data); + strlcpy(buffer, bootable ? "no" : "yes", size); + } + + } else if (!strcmp_l1("slot-retry-count:", cmd)) { + str += strlen("slot-retry-count:"); + slot = slotidx_from_suffix(str); + if (slot < 0) { + strlcpy(buffer, "no such slot", size); + return -1; + } + else { + slot_data = &ab_data.slots[slot]; + char var[7]; + sprintf(var, "%d", + slot_data->tries_remaining); + strlcpy(buffer, var, size); + } + + } else { + strlcpy(buffer, "no such slot command", size); + return -1; + } + + return 0; +} + +char *select_slot(AvbABOps *ab_ops) { + AvbABData ab_data; + int curr; + + assert(ab_ops != NULL); + + /* load ab meta */ + if (ab_ops->read_ab_metadata == NULL || + ab_ops->read_ab_metadata(ab_ops, &ab_data) != AVB_IO_RESULT_OK) { + return NULL; + } + curr = get_curr_slot(&ab_data); + if (curr >= 0 && curr < SLOT_NUM) + return slot_suffix[curr]; + else + return NULL; +} diff --git a/lib/avb/libavb/Makefile b/lib/avb/libavb/Makefile new file mode 100644 index 0000000..2badd60 --- /dev/null +++ b/lib/avb/libavb/Makefile @@ -0,0 +1,17 @@ +ccflags-y += -DAVB_COMPILATION +obj-y += avb_descriptor.o \ + avb_kernel_cmdline_descriptor.o \ + avb_sha512.o \ + avb_vbmeta_image.o \ + avb_chain_partition_descriptor.o \ + avb_footer.o \ + avb_property_descriptor.o \ + avb_slot_verify.o \ + avb_crc32.o \ + avb_hash_descriptor.o \ + avb_rsa.o \ + avb_crypto.o \ + avb_hashtree_descriptor.o \ + avb_sha256.o \ + avb_util.o \ + avb_sysdeps_uboot.o diff --git a/lib/avb/libavb/avb_ab_flow.c b/lib/avb/libavb/avb_ab_flow.c new file mode 100644 index 0000000..bcd6740 --- /dev/null +++ b/lib/avb/libavb/avb_ab_flow.c @@ -0,0 +1,441 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_ab_flow.h" +#include "avb_util.h" + +bool avb_ab_data_verify_and_byteswap(const AvbABData* src, AvbABData* dest) { + /* Ensure magic is correct. */ + if (avb_safe_memcmp(src->magic, AVB_AB_MAGIC, AVB_AB_MAGIC_LEN) != 0) { + avb_error("Magic is incorrect.\n"); + return false; + } + + avb_memcpy(dest, src, sizeof(AvbABData)); + dest->crc32 = avb_be32toh(dest->crc32); + + /* Ensure we don't attempt to access any fields if the major version + * is not supported. + */ + if (dest->version_major > AVB_AB_MAJOR_VERSION) { + avb_error("No support for given major version.\n"); + return false; + } + + /* Bail if CRC32 doesn't match. */ + if (dest->crc32 != + avb_crc32((const uint8_t*)dest, sizeof(AvbABData) - sizeof(uint32_t))) { + avb_error("CRC32 does not match.\n"); + return false; + } + + return true; +} + +void avb_ab_data_update_crc_and_byteswap(const AvbABData* src, + AvbABData* dest) { + avb_memcpy(dest, src, sizeof(AvbABData)); + dest->crc32 = avb_htobe32( + avb_crc32((const uint8_t*)dest, sizeof(AvbABData) - sizeof(uint32_t))); +} + +void avb_ab_data_init(AvbABData* data) { + avb_memset(data, '\0', sizeof(AvbABData)); + avb_memcpy(data->magic, AVB_AB_MAGIC, AVB_AB_MAGIC_LEN); + data->version_major = AVB_AB_MAJOR_VERSION; + data->version_minor = AVB_AB_MINOR_VERSION; + data->slots[0].priority = AVB_AB_MAX_PRIORITY; + data->slots[0].tries_remaining = AVB_AB_MAX_TRIES_REMAINING; + data->slots[0].successful_boot = 0; + data->slots[1].priority = AVB_AB_MAX_PRIORITY - 1; + data->slots[1].tries_remaining = AVB_AB_MAX_TRIES_REMAINING; + data->slots[1].successful_boot = 0; +} + +/* The AvbABData struct is stored 2048 bytes into the 'misc' partition + * following the 'struct bootloader_message' field. The struct is + * compatible with the guidelines in bootable/recovery/bootloader.h - + * e.g. it is stored in the |slot_suffix| field, starts with a + * NUL-byte, and is 32 bytes long. + */ +#define AB_METADATA_MISC_PARTITION_OFFSET 2048 + +AvbIOResult avb_ab_data_read(AvbOps* ops, AvbABData* data) { + AvbABData serialized; + AvbIOResult io_ret; + size_t num_bytes_read; + + io_ret = + ops->read_from_partition(ops, "misc", AB_METADATA_MISC_PARTITION_OFFSET, + sizeof(AvbABData), &serialized, &num_bytes_read); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + return AVB_IO_RESULT_ERROR_OOM; + } else if (io_ret != AVB_IO_RESULT_OK || + num_bytes_read != sizeof(AvbABData)) { + avb_error("Error reading A/B metadata.\n"); + return AVB_IO_RESULT_ERROR_IO; + } + + if (!avb_ab_data_verify_and_byteswap(&serialized, data)) { + avb_error( + "Error validating A/B metadata from disk. " + "Resetting and writing new A/B metadata to disk.\n"); + avb_ab_data_init(data); + return avb_ab_data_write(ops, data); + } + + return AVB_IO_RESULT_OK; +} + +AvbIOResult avb_ab_data_write(AvbOps* ops, const AvbABData* data) { + AvbABData serialized; + AvbIOResult io_ret; + + avb_ab_data_update_crc_and_byteswap(data, &serialized); + io_ret = + ops->write_to_partition(ops, "misc", AB_METADATA_MISC_PARTITION_OFFSET, + sizeof(AvbABData), &serialized); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + return AVB_IO_RESULT_ERROR_OOM; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_error("Error writing A/B metadata.\n"); + return AVB_IO_RESULT_ERROR_IO; + } + return AVB_IO_RESULT_OK; +} + +static bool slot_is_bootable(AvbABSlotData* slot) { + return slot->priority > 0 && + (slot->successful_boot || (slot->tries_remaining > 0)); +} + +static void slot_set_unbootable(AvbABSlotData* slot) { + slot->priority = 0; + slot->tries_remaining = 0; + slot->successful_boot = 0; +} + +/* Ensure all unbootable and/or illegal states are marked as the + * canonical 'unbootable' state, e.g. priority=0, tries_remaining=0, + * and successful_boot=0. + */ +static void slot_normalize(AvbABSlotData* slot) { + if (slot->priority > 0) { + if (slot->tries_remaining == 0 && !slot->successful_boot) { + /* We've exhausted all tries -> unbootable. */ + slot_set_unbootable(slot); + } + if (slot->tries_remaining > 0 && slot->successful_boot) { + /* Illegal state - avb_ab_mark_slot_successful() will clear + * tries_remaining when setting successful_boot. + */ + slot_set_unbootable(slot); + } + } else { + slot_set_unbootable(slot); + } +} + +static const char* slot_suffixes[2] = {"_a", "_b"}; + +/* Helper function to load metadata - returns AVB_IO_RESULT_OK on + * success, error code otherwise. + */ +static AvbIOResult load_metadata(AvbOps* ops, AvbABData* ab_data, + AvbABData* ab_data_orig) { + AvbIOResult io_ret; + + io_ret = ops->read_ab_metadata(ops, ab_data); + if (io_ret != AVB_IO_RESULT_OK) { + avb_error("I/O error while loading A/B metadata.\n"); + return io_ret; + } + *ab_data_orig = *ab_data; + + /* Ensure data is normalized, e.g. illegal states will be marked as + * unbootable and all unbootable states are represented with + * (priority=0, tries_remaining=0, successful_boot=0). + */ + slot_normalize(&ab_data->slots[0]); + slot_normalize(&ab_data->slots[1]); + return AVB_IO_RESULT_OK; +} + +/* Writes A/B metadata to disk only if it has changed - returns + * AVB_IO_RESULT_OK on success, error code otherwise. + */ +static AvbIOResult save_metadata_if_changed(AvbOps* ops, AvbABData* ab_data, + AvbABData* ab_data_orig) { + if (avb_safe_memcmp(ab_data, ab_data_orig, sizeof(AvbABData)) != 0) { + avb_debug("Writing A/B metadata to disk.\n"); + return ops->write_ab_metadata(ops, ab_data); + } + return AVB_IO_RESULT_OK; +} + +AvbABFlowResult avb_ab_flow(AvbOps* ops, + const char* const* requested_partitions, + AvbSlotVerifyData** out_data) { + AvbSlotVerifyData* slot_data[2] = {NULL, NULL}; + AvbSlotVerifyData* data = NULL; + AvbABFlowResult ret; + AvbABData ab_data, ab_data_orig; + size_t slot_index_to_boot, n; + bool is_device_unlocked; + AvbIOResult io_ret; + + io_ret = load_metadata(ops, &ab_data, &ab_data_orig); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_AB_FLOW_RESULT_ERROR_OOM; + goto out; + } else if (io_ret != AVB_IO_RESULT_OK) { + ret = AVB_AB_FLOW_RESULT_ERROR_IO; + goto out; + } + + /* Validate all bootable slots. */ + for (n = 0; n < 2; n++) { + if (slot_is_bootable(&ab_data.slots[n])) { + AvbSlotVerifyResult verify_result; + verify_result = avb_slot_verify(ops, requested_partitions, + slot_suffixes[n], &slot_data[n]); + if (verify_result != AVB_SLOT_VERIFY_RESULT_OK) { + if (verify_result == AVB_SLOT_VERIFY_RESULT_ERROR_OOM) { + ret = AVB_AB_FLOW_RESULT_ERROR_OOM; + goto out; + } + if (verify_result == AVB_SLOT_VERIFY_RESULT_ERROR_IO) { + ret = AVB_AB_FLOW_RESULT_ERROR_IO; + goto out; + } + avb_errorv("Error verifying slot ", slot_suffixes[n], " with result ", + avb_slot_verify_result_to_string(verify_result), + " - setting unbootable.\n", NULL); + slot_set_unbootable(&ab_data.slots[n]); + } + } + } + + if (slot_is_bootable(&ab_data.slots[0]) && + slot_is_bootable(&ab_data.slots[1])) { + if (ab_data.slots[1].priority > ab_data.slots[0].priority) { + slot_index_to_boot = 1; + } else { + slot_index_to_boot = 0; + } + } else if (slot_is_bootable(&ab_data.slots[0])) { + slot_index_to_boot = 0; + } else if (slot_is_bootable(&ab_data.slots[1])) { + slot_index_to_boot = 1; + } else { + /* No bootable slots! */ + avb_error("No bootable slots found.\n"); + ret = AVB_AB_FLOW_RESULT_ERROR_NO_BOOTABLE_SLOTS; + goto out; + } + + /* Update stored rollback index such that the stored rollback index + * is the largest value supporting all currently bootable slots. Do + * this for every rollback index slot. + */ + for (n = 0; n < AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_SLOTS; n++) { + uint64_t rollback_index_value = 0; + + if (slot_data[0] != NULL && slot_data[1] != NULL) { + uint64_t a_rollback_index = slot_data[0]->rollback_indexes[n]; + uint64_t b_rollback_index = slot_data[1]->rollback_indexes[n]; + rollback_index_value = + (a_rollback_index < b_rollback_index ? a_rollback_index + : b_rollback_index); + } else if (slot_data[0] != NULL) { + rollback_index_value = slot_data[0]->rollback_indexes[n]; + } else if (slot_data[1] != NULL) { + rollback_index_value = slot_data[1]->rollback_indexes[n]; + } + + if (rollback_index_value != 0) { + uint64_t current_rollback_index_value; + io_ret = ops->read_rollback_index(ops, n, ¤t_rollback_index_value); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_AB_FLOW_RESULT_ERROR_OOM; + goto out; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_error("Error getting rollback index for slot.\n"); + ret = AVB_AB_FLOW_RESULT_ERROR_IO; + goto out; + } + if (current_rollback_index_value != rollback_index_value) { + io_ret = ops->write_rollback_index(ops, n, rollback_index_value); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_AB_FLOW_RESULT_ERROR_OOM; + goto out; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_error("Error setting stored rollback index.\n"); + ret = AVB_AB_FLOW_RESULT_ERROR_IO; + goto out; + } + } + } + } + + /* Finally, select this slot. */ + avb_assert(slot_data[slot_index_to_boot] != NULL); + data = slot_data[slot_index_to_boot]; + slot_data[slot_index_to_boot] = NULL; + ret = AVB_AB_FLOW_RESULT_OK; + + /* ... and decrement tries remaining, if applicable. */ + if (!ab_data.slots[slot_index_to_boot].successful_boot && + ab_data.slots[slot_index_to_boot].tries_remaining > 0) { + ab_data.slots[slot_index_to_boot].tries_remaining -= 1; + } + +out: + /* do not touch metadata in UNLOCK state */ + io_ret = ops->read_is_device_unlocked(ops, &is_device_unlocked); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_AB_FLOW_RESULT_ERROR_OOM; + goto fail; + } else if (io_ret != AVB_IO_RESULT_OK) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; + avb_error("Error getting device state.\n"); + goto fail; + } + if (is_device_unlocked) + goto ret; + +fail: + io_ret = save_metadata_if_changed(ops, &ab_data, &ab_data_orig); + if (io_ret != AVB_IO_RESULT_OK) { + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_AB_FLOW_RESULT_ERROR_OOM; + } else { + ret = AVB_AB_FLOW_RESULT_ERROR_IO; + } + if (data != NULL) { + avb_slot_verify_data_free(data); + data = NULL; + } + } + +ret: + for (n = 0; n < 2; n++) { + if (slot_data[n] != NULL) { + avb_slot_verify_data_free(slot_data[n]); + } + } + + if (out_data != NULL) { + *out_data = data; + } else { + if (data != NULL) { + avb_slot_verify_data_free(data); + } + } + + return ret; +} + +AvbIOResult avb_ab_mark_slot_active(AvbOps* ops, unsigned int slot_number) { + AvbABData ab_data, ab_data_orig; + unsigned int other_slot_number; + AvbIOResult ret; + + avb_assert(slot_number < 2); + + ret = load_metadata(ops, &ab_data, &ab_data_orig); + if (ret != AVB_IO_RESULT_OK) { + goto out; + } + + /* Make requested slot top priority, unsuccessful, and with max tries. */ + ab_data.slots[slot_number].priority = AVB_AB_MAX_PRIORITY; + ab_data.slots[slot_number].tries_remaining = AVB_AB_MAX_TRIES_REMAINING; + ab_data.slots[slot_number].successful_boot = 0; + + /* Ensure other slot doesn't have as high a priority. */ + other_slot_number = 1 - slot_number; + if (ab_data.slots[other_slot_number].priority == AVB_AB_MAX_PRIORITY) { + ab_data.slots[other_slot_number].priority = AVB_AB_MAX_PRIORITY - 1; + } + + ret = AVB_IO_RESULT_OK; + +out: + if (ret == AVB_IO_RESULT_OK) { + ret = save_metadata_if_changed(ops, &ab_data, &ab_data_orig); + } + return ret; +} + +AvbIOResult avb_ab_mark_slot_unbootable(AvbOps* ops, unsigned int slot_number) { + AvbABData ab_data, ab_data_orig; + AvbIOResult ret; + + avb_assert(slot_number < 2); + + ret = load_metadata(ops, &ab_data, &ab_data_orig); + if (ret != AVB_IO_RESULT_OK) { + goto out; + } + + slot_set_unbootable(&ab_data.slots[slot_number]); + + ret = AVB_IO_RESULT_OK; + +out: + if (ret == AVB_IO_RESULT_OK) { + ret = save_metadata_if_changed(ops, &ab_data, &ab_data_orig); + } + return ret; +} + +AvbIOResult avb_ab_mark_slot_successful(AvbOps* ops, unsigned int slot_number) { + AvbABData ab_data, ab_data_orig; + AvbIOResult ret; + + avb_assert(slot_number < 2); + + ret = load_metadata(ops, &ab_data, &ab_data_orig); + if (ret != AVB_IO_RESULT_OK) { + goto out; + } + + if (!slot_is_bootable(&ab_data.slots[slot_number])) { + avb_error("Cannot mark unbootable slot as successful.\n"); + ret = AVB_IO_RESULT_OK; + goto out; + } + + ab_data.slots[slot_number].tries_remaining = 0; + ab_data.slots[slot_number].successful_boot = 1; + + ret = AVB_IO_RESULT_OK; + +out: + if (ret == AVB_IO_RESULT_OK) { + ret = save_metadata_if_changed(ops, &ab_data, &ab_data_orig); + } + return ret; +} diff --git a/lib/avb/libavb/avb_ab_flow.h b/lib/avb/libavb/avb_ab_flow.h new file mode 100644 index 0000000..c19f846 --- /dev/null +++ b/lib/avb/libavb/avb_ab_flow.h @@ -0,0 +1,226 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_AB_FLOW_H_ +#define AVB_AB_FLOW_H_ + +#include "avb_ops.h" +#include "avb_slot_verify.h" +#include "avb_vbmeta_image.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* Magic for the A/B struct when serialized. */ +#define AVB_AB_MAGIC "\0AB0" +#define AVB_AB_MAGIC_LEN 4 + +/* Versioning for the on-disk A/B metadata - keep in sync with avbtool. */ +#define AVB_AB_MAJOR_VERSION 1 +#define AVB_AB_MINOR_VERSION 0 + +/* Size of AvbABData struct. */ +#define AVB_AB_DATA_SIZE 32 + +/* Maximum values for slot data */ +#define AVB_AB_MAX_PRIORITY 15 +#define AVB_AB_MAX_TRIES_REMAINING 7 + +/* Struct used for recording per-slot metadata. + * + * When serialized, data is stored in network byte-order. + */ +typedef struct AvbABSlotData { + /* Slot priority. Valid values range from 0 to AVB_AB_MAX_PRIORITY, + * both inclusive with 1 being the lowest and AVB_AB_MAX_PRIORITY + * being the highest. The special value 0 is used to indicate the + * slot is unbootable. + */ + uint8_t priority; + + /* Number of times left attempting to boot this slot ranging from 0 + * to AVB_AB_MAX_TRIES_REMAINING. + */ + uint8_t tries_remaining; + + /* Non-zero if this slot has booted successfully, 0 otherwise. */ + uint8_t successful_boot; + + /* Reserved for future use. */ + uint8_t reserved[1]; +} AVB_ATTR_PACKED AvbABSlotData; + +/* Struct used for recording A/B metadata. + * + * When serialized, data is stored in network byte-order. + */ +typedef struct AvbABData { + /* Magic number used for identification - see AVB_AB_MAGIC. */ + uint8_t magic[AVB_AB_MAGIC_LEN]; + + /* Version of on-disk struct - see AVB_AB_{MAJOR,MINOR}_VERSION. */ + uint8_t version_major; + uint8_t version_minor; + + /* Padding to ensure |slots| field start eight bytes in. */ + uint8_t reserved1[2]; + + /* Per-slot metadata. */ + AvbABSlotData slots[2]; + + /* Reserved for future use. */ + uint8_t reserved2[12]; + + /* CRC32 of all 28 bytes preceding this field. */ + uint32_t crc32; +} AVB_ATTR_PACKED AvbABData; + +/* Copies |src| to |dest|, byte-swapping fields in the + * process. Returns false if the data is invalid (e.g. wrong magic, + * wrong CRC32 etc.), true otherwise. + */ +bool avb_ab_data_verify_and_byteswap(const AvbABData* src, AvbABData* dest); + +/* Copies |src| to |dest|, byte-swapping fields in the process. Also + * updates the |crc32| field in |dest|. + */ +void avb_ab_data_update_crc_and_byteswap(const AvbABData* src, AvbABData* dest); + +/* Initializes |data| such that it has two slots and both slots have + * maximum tries remaining. The CRC is not set. + */ +void avb_ab_data_init(AvbABData* data); + +/* Reads A/B metadata from the 'misc' partition using |ops|. Returned + * data is properly byteswapped. Returns AVB_IO_RESULT_OK on + * success, error code otherwise. + * + * If the data read from disk is invalid (e.g. wrong magic or CRC + * checksum failure), the metadata will be reset using + * avb_ab_data_init() and then written to disk. + */ +AvbIOResult avb_ab_data_read(AvbOps* ops, AvbABData* data); + +/* Writes A/B metadata to the 'misc' partition using |ops|. This will + * byteswap and update the CRC as needed. Returns AVB_IO_RESULT_OK on + * success, error code otherwise. + */ +AvbIOResult avb_ab_data_write(AvbOps* ops, const AvbABData* data); + +/* Return codes used in avb_ab_flow(), see that function for + * documentation of each value. + */ +typedef enum { + AVB_AB_FLOW_RESULT_OK, + AVB_AB_FLOW_RESULT_ERROR_OOM, + AVB_AB_FLOW_RESULT_ERROR_IO, + AVB_AB_FLOW_RESULT_ERROR_NO_BOOTABLE_SLOTS +} AvbABFlowResult; + +/* High-level function to select a slot to boot. The following + * algorithm is used: + * + * 1. A/B metadata is loaded and validated using the + * read_ab_metadata() operation. Typically this means it's read from + * the 'misc' partition and if it's invalid then it's reset using + * avb_ab_data_init() and this reset metadata is returned. + * + * 2. All bootable slots listed in the A/B metadata are verified using + * avb_slot_verify(). If a slot fails verification, it will be marked + * as unbootable in the A/B metadata and the metadata will be saved to + * disk before returning. + * + * 3. If there are no bootable slots, the value + * AVB_AB_FLOW_RESULT_ERROR_NO_BOOTABLE_SLOTS is returned. + * + * 4. For each bootable slot, the Stored Rollback Indexes are updated + * such that for each rollback index slot, the Stored Rollback Index + * is the largest number smaller than or equal to the Rollback Index + * of each slot. + * + * 5. The bootable slot with the highest priority is selected and + * returned in |out_data|. If this slot is already marked as + * successful, the A/B metadata is not modified. However, if the slot + * is not marked as bootable its |tries_remaining| count is + * decremented and the A/B metadata is saved to disk before returning. + * In either case the value AVB_AB_FLOW_RESULT_OK is returning. + * + * The partitions to load is given in |requested_partitions| as a + * NULL-terminated array of NUL-terminated strings. Typically the + * |requested_partitions| array only contains a single item for the + * boot partition, 'boot'. + * + * If an I/O operation - such as loading/saving metadata or checking + * rollback indexes - fail, the value AVB_AB_FLOW_RESULT_ERROR_IO is + * returned. + * + * If memory allocation fails, AVB_AB_FLOW_RESULT_ERROR_OOM is + * returned. + * + * Reasonable behavior for handling AVB_AB_FLOW_RESULT_ERROR_NO_BOOTABLE_SLOTS + * is to initiate device recovery (which is device-dependent). + */ +AvbABFlowResult avb_ab_flow(AvbOps* ops, + const char* const* requested_partitions, + AvbSlotVerifyData** out_data); + +/* Marks the slot with the given slot number as active. Returns + * AVB_IO_RESULT_OK on success, error code otherwise. + * + * This function is typically used by the OS updater when completing + * an update. It can also used by the firmware for implementing the + * "set_active" command. + */ +AvbIOResult avb_ab_mark_slot_active(AvbOps* ops, unsigned int slot_number); + +/* Marks the slot with the given slot number as unbootable. Returns + * AVB_IO_RESULT_OK on success, error code otherwise. + * + * This function is typically used by the OS updater before writing to + * a slot. + */ +AvbIOResult avb_ab_mark_slot_unbootable(AvbOps* ops, unsigned int slot_number); + +/* Marks the slot with the given slot number as having booted + * successfully. Returns AVB_IO_RESULT_OK on success, error code + * otherwise. + * + * Calling this on an unbootable slot is an error - AVB_IO_RESULT_OK + * will be returned yet the function will have no side-effects. + * + * This function is typically used by the OS updater after having + * confirmed that the slot works as intended. + */ +AvbIOResult avb_ab_mark_slot_successful(AvbOps* ops, unsigned int slot_number); + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_AB_FLOW_H_ */ diff --git a/lib/avb/libavb/avb_chain_partition_descriptor.c b/lib/avb/libavb/avb_chain_partition_descriptor.c new file mode 100644 index 0000000..40e8bb5 --- /dev/null +++ b/lib/avb/libavb/avb_chain_partition_descriptor.c @@ -0,0 +1,64 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_chain_partition_descriptor.h" +#include "avb_util.h" + +bool avb_chain_partition_descriptor_validate_and_byteswap( + const AvbChainPartitionDescriptor* src, AvbChainPartitionDescriptor* dest) { + uint64_t expected_size; + + avb_memcpy(dest, src, sizeof(AvbChainPartitionDescriptor)); + + if (!avb_descriptor_validate_and_byteswap((const AvbDescriptor*)src, + (AvbDescriptor*)dest)) + return false; + + if (dest->parent_descriptor.tag != AVB_DESCRIPTOR_TAG_CHAIN_PARTITION) { + avb_error("Invalid tag for chain partition descriptor.\n"); + return false; + } + + dest->rollback_index_slot = avb_be32toh(dest->rollback_index_slot); + dest->partition_name_len = avb_be32toh(dest->partition_name_len); + dest->public_key_len = avb_be32toh(dest->public_key_len); + + if (dest->rollback_index_slot < 1) { + avb_error("Invalid rollback index slot value.\n"); + return false; + } + + /* Check that partition_name and public_key are fully contained. */ + expected_size = sizeof(AvbChainPartitionDescriptor) - sizeof(AvbDescriptor); + if (!avb_safe_add_to(&expected_size, dest->partition_name_len) || + !avb_safe_add_to(&expected_size, dest->public_key_len)) { + avb_error("Overflow while adding up sizes.\n"); + return false; + } + if (expected_size > dest->parent_descriptor.num_bytes_following) { + avb_error("Descriptor payload size overflow.\n"); + return false; + } + return true; +} diff --git a/lib/avb/libavb/avb_chain_partition_descriptor.h b/lib/avb/libavb/avb_chain_partition_descriptor.h new file mode 100644 index 0000000..817f74f --- /dev/null +++ b/lib/avb/libavb/avb_chain_partition_descriptor.h @@ -0,0 +1,72 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_CHAIN_PARTITION_DESCRIPTOR_H_ +#define AVB_CHAIN_PARTITION_DESCRIPTOR_H_ + +#include "avb_descriptor.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* A descriptor containing a pointer to signed integrity data stored + * on another partition. The descriptor contains the partition name in + * question (without the A/B suffix), the public key used to sign the + * integrity data, and rollback index slot to use for rollback + * protection. + * + * Following this struct are |partition_name_len| bytes of the + * partition name (UTF-8 encoded) and |public_key_len| bytes of the + * public key. + * + * The |reserved| field is for future expansion and must be set to NUL + * bytes. + */ +typedef struct AvbChainPartitionDescriptor { + AvbDescriptor parent_descriptor; + uint32_t rollback_index_slot; + uint32_t partition_name_len; + uint32_t public_key_len; + uint8_t reserved[64]; +} AVB_ATTR_PACKED AvbChainPartitionDescriptor; + +/* Copies |src| to |dest| and validates, byte-swapping fields in the + * process if needed. Returns true if valid, false if invalid. + * + * Data following the struct is not validated nor copied. + */ +bool avb_chain_partition_descriptor_validate_and_byteswap( + const AvbChainPartitionDescriptor* src, + AvbChainPartitionDescriptor* dest) AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_CHAIN_PARTITION_DESCRIPTOR_H_ */ diff --git a/lib/avb/libavb/avb_crc32.c b/lib/avb/libavb/avb_crc32.c new file mode 100644 index 0000000..55971af --- /dev/null +++ b/lib/avb/libavb/avb_crc32.c @@ -0,0 +1,112 @@ +/*- + * COPYRIGHT (C) 1986 Gary S. Brown. You may use this program, or + * code or tables extracted from it, as desired without restriction. + */ + +/* + * First, the polynomial itself and its table of feedback terms. The + * polynomial is + * X^32+X^26+X^23+X^22+X^16+X^12+X^11+X^10+X^8+X^7+X^5+X^4+X^2+X^1+X^0 + * + * Note that we take it "backwards" and put the highest-order term in + * the lowest-order bit. The X^32 term is "implied"; the LSB is the + * X^31 term, etc. The X^0 term (usually shown as "+1") results in + * the MSB being 1 + * + * Note that the usual hardware shift register implementation, which + * is what we're using (we're merely optimizing it by doing eight-bit + * chunks at a time) shifts bits into the lowest-order term. In our + * implementation, that means shifting towards the right. Why do we + * do it this way? Because the calculated CRC must be transmitted in + * order from highest-order term to lowest-order term. UARTs transmit + * characters in order from LSB to MSB. By storing the CRC this way + * we hand it to the UART in the order low-byte to high-byte; the UART + * sends each low-bit to hight-bit; and the result is transmission bit + * by bit from highest- to lowest-order term without requiring any bit + * shuffling on our part. Reception works similarly + * + * The feedback terms table consists of 256, 32-bit entries. Notes + * + * The table can be generated at runtime if desired; code to do so + * is shown later. It might not be obvious, but the feedback + * terms simply represent the results of eight shift/xor opera + * tions for all combinations of data and CRC register values + * + * The values must be right-shifted by eight bits by the "updcrc + * logic; the shift must be unsigned (bring in zeroes). On some + * hardware you could probably optimize the shift in assembler by + * using byte-swap instructions + * polynomial $edb88320 + * + * + * CRC32 code derived from work by Gary S. Brown. + */ + +#include "avb_sysdeps.h" + +/* Code taken from FreeBSD 8 */ + +static uint32_t crc32_tab[] = { + 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, + 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, + 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, + 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, + 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, + 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, + 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, + 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, + 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, + 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, + 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106, + 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, + 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, + 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, + 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, + 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, + 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, + 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, + 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, + 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, + 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, + 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, + 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, + 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, + 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, + 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, + 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e, + 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, + 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, + 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, + 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, + 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, + 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, + 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, + 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, + 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, + 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, + 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, + 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, + 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, + 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, + 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, + 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d}; + +/* + * A function that calculates the CRC-32 based on the table above is + * given below for documentation purposes. An equivalent implementation + * of this function that's actually used in the kernel can be found + * in sys/libkern.h, where it can be inlined. + */ + +static uint32_t crc32(uint32_t crc_in, const uint8_t* buf, int size) { + const uint8_t* p = buf; + uint32_t crc; + + crc = crc_in ^ ~0U; + while (size--) crc = crc32_tab[(crc ^ *p++) & 0xFF] ^ (crc >> 8); + return crc ^ ~0U; +} + +uint32_t avb_crc32(const uint8_t* buf, size_t size) { + return crc32(0, buf, size); +} diff --git a/lib/avb/libavb/avb_crypto.c b/lib/avb/libavb/avb_crypto.c new file mode 100644 index 0000000..9bd4720 --- /dev/null +++ b/lib/avb/libavb/avb_crypto.c @@ -0,0 +1,38 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_crypto.h" +#include "avb_rsa.h" +#include "avb_sha.h" +#include "avb_util.h" + +bool avb_rsa_public_key_header_validate_and_byteswap( + const AvbRSAPublicKeyHeader* src, AvbRSAPublicKeyHeader* dest) { + avb_memcpy(dest, src, sizeof(AvbRSAPublicKeyHeader)); + + dest->key_num_bits = avb_be32toh(dest->key_num_bits); + dest->n0inv = avb_be32toh(dest->n0inv); + + return true; +} diff --git a/lib/avb/libavb/avb_crypto.h b/lib/avb/libavb/avb_crypto.h new file mode 100644 index 0000000..40740c3 --- /dev/null +++ b/lib/avb/libavb/avb_crypto.h @@ -0,0 +1,137 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_CRYPTO_H_ +#define AVB_CRYPTO_H_ + +#include "avb_sysdeps.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* Algorithms that can be used in the vbmeta image for + * verification. An algorithm consists of a hash type and a signature + * type. + * + * The data used to calculate the hash is the three blocks mentioned + * in the documentation for |AvbVBMetaImageHeader| except for the data + * in the "Authentication data" block. + * + * For signatures with RSA keys, PKCS v1.5 padding is used. The public + * key data is stored in the auxiliary data block, see + * |AvbRSAPublicKeyHeader| for the serialization format. + * + * Each algorithm type is described below: + * + * AVB_ALGORITHM_TYPE_NONE: There is no hash, no signature of the + * data, and no public key. The data cannot be verified. The fields + * |hash_size|, |signature_size|, and |public_key_size| must be zero. + * + * AVB_ALGORITHM_TYPE_SHA256_RSA2048: The hash function used is + * SHA-256, resulting in 32 bytes of hash digest data. This hash is + * signed with a 2048-bit RSA key. The field |hash_size| must be 32, + * |signature_size| must be 256, and the public key data must have + * |key_num_bits| set to 2048. + * + * AVB_ALGORITHM_TYPE_SHA256_RSA4096: Like above, but only with + * a 4096-bit RSA key and |signature_size| set to 512. + * + * AVB_ALGORITHM_TYPE_SHA256_RSA8192: Like above, but only with + * a 8192-bit RSA key and |signature_size| set to 1024. + * + * AVB_ALGORITHM_TYPE_SHA512_RSA2048: The hash function used is + * SHA-512, resulting in 64 bytes of hash digest data. This hash is + * signed with a 2048-bit RSA key. The field |hash_size| must be 64, + * |signature_size| must be 256, and the public key data must have + * |key_num_bits| set to 2048. + * + * AVB_ALGORITHM_TYPE_SHA512_RSA4096: Like above, but only with + * a 4096-bit RSA key and |signature_size| set to 512. + * + * AVB_ALGORITHM_TYPE_SHA512_RSA8192: Like above, but only with + * a 8192-bit RSA key and |signature_size| set to 1024. + */ +typedef enum { + AVB_ALGORITHM_TYPE_NONE, + AVB_ALGORITHM_TYPE_SHA256_RSA2048, + AVB_ALGORITHM_TYPE_SHA256_RSA4096, + AVB_ALGORITHM_TYPE_SHA256_RSA8192, + AVB_ALGORITHM_TYPE_SHA512_RSA2048, + AVB_ALGORITHM_TYPE_SHA512_RSA4096, + AVB_ALGORITHM_TYPE_SHA512_RSA8192, + _AVB_ALGORITHM_NUM_TYPES +} AvbAlgorithmType; + +/* The header for a serialized RSA public key. + * + * The size of the key is given by |key_num_bits|, for example 2048 + * for a RSA-2048 key. By definition, a RSA public key is the pair (n, + * e) where |n| is the modulus (which can be represented in + * |key_num_bits| bits) and |e| is the public exponent. The exponent + * is not stored since it's assumed to always be 65537. + * + * To optimize verification, the key block includes two precomputed + * values, |n0inv| (fits in 32 bits) and |rr| and can always be + * represented in |key_num_bits|. + + * The value |n0inv| is the value -1/n[0] (mod 2^32). The value |rr| + * is (2^key_num_bits)^2 (mod n). + * + * Following this header is |key_num_bits| bits of |n|, then + * |key_num_bits| bits of |rr|. Both values are stored with most + * significant bit first. Each serialized number takes up + * |key_num_bits|/8 bytes. + * + * All fields in this struct are stored in network byte order when + * serialized. To generate a copy with fields swapped to native byte + * order, use the function avb_rsa_public_key_header_validate_and_byteswap(). + * + * The avb_rsa_verify() function expects a key in this serialized + * format. + * + * The 'avbtool extract_public_key' command can be used to generate a + * serialized RSA public key. + */ +typedef struct AvbRSAPublicKeyHeader { + uint32_t key_num_bits; + uint32_t n0inv; +} AVB_ATTR_PACKED AvbRSAPublicKeyHeader; + +/* Copies |src| to |dest| and validates, byte-swapping fields in the + * process if needed. Returns true if valid, false if invalid. + */ +bool avb_rsa_public_key_header_validate_and_byteswap( + const AvbRSAPublicKeyHeader* src, + AvbRSAPublicKeyHeader* dest) AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_CRYPTO_H_ */ diff --git a/lib/avb/libavb/avb_descriptor.c b/lib/avb/libavb/avb_descriptor.c new file mode 100644 index 0000000..db465aa --- /dev/null +++ b/lib/avb/libavb/avb_descriptor.c @@ -0,0 +1,159 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_descriptor.h" +#include "avb_util.h" +#include "avb_vbmeta_image.h" + +bool avb_descriptor_validate_and_byteswap(const AvbDescriptor* src, + AvbDescriptor* dest) { + dest->tag = avb_be64toh(src->tag); + dest->num_bytes_following = avb_be64toh(src->num_bytes_following); + + if ((dest->num_bytes_following & 0x07) != 0) { + avb_error("Descriptor size is not divisible by 8.\n"); + return false; + } + return true; +} + +bool avb_descriptor_foreach(const uint8_t* image_data, size_t image_size, + AvbDescriptorForeachFunc foreach_func, + void* user_data) { + const AvbVBMetaImageHeader* header = NULL; + bool ret = false; + const uint8_t* image_end; + const uint8_t* desc_start; + const uint8_t* desc_end; + const uint8_t* p; + + if (image_data == NULL) { + avb_error("image_data is NULL\n."); + goto out; + } + + if (foreach_func == NULL) { + avb_error("foreach_func is NULL\n."); + goto out; + } + + if (image_size < sizeof(AvbVBMetaImageHeader)) { + avb_error("Length is smaller than header.\n"); + goto out; + } + + /* Ensure magic is correct. */ + if (avb_memcmp(image_data, AVB_MAGIC, AVB_MAGIC_LEN) != 0) { + avb_error("Magic is incorrect.\n"); + goto out; + } + + /* Careful, not byteswapped - also ensure it's aligned properly. */ + avb_assert_word_aligned(image_data); + header = (const AvbVBMetaImageHeader*)image_data; + image_end = image_data + image_size; + + desc_start = image_data + sizeof(AvbVBMetaImageHeader) + + avb_be64toh(header->authentication_data_block_size) + + avb_be64toh(header->descriptors_offset); + + desc_end = desc_start + avb_be64toh(header->descriptors_size); + + if (desc_start < image_data || desc_start > image_end || + desc_end < image_data || desc_end > image_end || desc_end < desc_start) { + avb_error("Descriptors not inside passed-in data.\n"); + goto out; + } + + for (p = desc_start; p < desc_end;) { + const AvbDescriptor* dh = (const AvbDescriptor*)p; + avb_assert_word_aligned(dh); + uint64_t nb_following = avb_be64toh(dh->num_bytes_following); + uint64_t nb_total = sizeof(AvbDescriptor) + nb_following; + + if ((nb_total & 7) != 0) { + avb_error("Invalid descriptor length.\n"); + goto out; + } + + if (nb_total + p < desc_start || nb_total + p > desc_end) { + avb_error("Invalid data in descriptors array.\n"); + goto out; + } + + if (foreach_func(dh, user_data) == 0) { + goto out; + } + + p += nb_total; + } + + ret = true; + +out: + return ret; +} + +static bool count_descriptors(const AvbDescriptor* descriptor, + void* user_data) { + size_t* num_descriptors = user_data; + *num_descriptors += 1; + return true; +} + +typedef struct { + size_t descriptor_number; + const AvbDescriptor** descriptors; +} SetDescriptorData; + +static bool set_descriptors(const AvbDescriptor* descriptor, void* user_data) { + SetDescriptorData* data = user_data; + data->descriptors[data->descriptor_number++] = descriptor; + return true; +} + +const AvbDescriptor** avb_descriptor_get_all(const uint8_t* image_data, + size_t image_size, + size_t* out_num_descriptors) { + size_t num_descriptors = 0; + SetDescriptorData data; + + avb_descriptor_foreach(image_data, image_size, count_descriptors, + &num_descriptors); + + data.descriptor_number = 0; + data.descriptors = + avb_calloc(sizeof(const AvbDescriptor*) * (num_descriptors + 1)); + if (data.descriptors == NULL) { + return NULL; + } + avb_descriptor_foreach(image_data, image_size, set_descriptors, &data); + avb_assert(data.descriptor_number == num_descriptors); + + if (out_num_descriptors != NULL) { + *out_num_descriptors = num_descriptors; + } + + return data.descriptors; +} diff --git a/lib/avb/libavb/avb_descriptor.h b/lib/avb/libavb/avb_descriptor.h new file mode 100644 index 0000000..8086a12 --- /dev/null +++ b/lib/avb/libavb/avb_descriptor.h @@ -0,0 +1,129 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_DESCRIPTOR_H_ +#define AVB_DESCRIPTOR_H_ + +#include "avb_sysdeps.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* Well-known descriptor tags. + * + * AVB_DESCRIPTOR_TAG_PROPERTY: see |AvbPropertyDescriptor| struct. + * AVB_DESCRIPTOR_TAG_HASHTREE: see |AvbHashtreeDescriptor| struct. + * AVB_DESCRIPTOR_TAG_HASH: see |AvbHashDescriptor| struct. + * AVB_DESCRIPTOR_TAG_KERNEL_CMDLINE: see |AvbKernelCmdlineDescriptor| struct. + * AVB_DESCRIPTOR_TAG_CHAIN_PARTITION: see |AvbChainPartitionDescriptor| struct. + */ +typedef enum { + AVB_DESCRIPTOR_TAG_PROPERTY, + AVB_DESCRIPTOR_TAG_HASHTREE, + AVB_DESCRIPTOR_TAG_HASH, + AVB_DESCRIPTOR_TAG_KERNEL_CMDLINE, + AVB_DESCRIPTOR_TAG_CHAIN_PARTITION, +} AvbDescriptorTag; + +/* The header for a serialized descriptor. + * + * A descriptor always have two fields, a |tag| (denoting its type, + * see the |AvbDescriptorTag| enumeration) and the size of the bytes + * following, |num_bytes_following|. + * + * For padding, |num_bytes_following| is always a multiple of 8. + */ +typedef struct AvbDescriptor { + uint64_t tag; + uint64_t num_bytes_following; +} AVB_ATTR_PACKED AvbDescriptor; + +/* Copies |src| to |dest| and validates, byte-swapping fields in the + * process if needed. Returns true if valid, false if invalid. + * + * Data following the struct is not validated nor copied. + */ +bool avb_descriptor_validate_and_byteswap( + const AvbDescriptor* src, AvbDescriptor* dest) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Signature for callback function used in avb_descriptor_foreach(). + * The passed in descriptor is given by |descriptor| and the + * |user_data| passed to avb_descriptor_foreach() function is in + * |user_data|. Return true to continue iterating, false to stop + * iterating. + * + * Note that |descriptor| points into the image passed to + * avb_descriptor_foreach() - all fields need to be byteswapped! + */ +typedef bool AvbDescriptorForeachFunc(const AvbDescriptor* descriptor, + void* user_data); + +/* Convenience function to iterate over all descriptors in an vbmeta + * image. + * + * The function given by |foreach_func| will be called for each + * descriptor. The given function should return true to continue + * iterating, false to stop. + * + * The |user_data| parameter will be passed to |foreach_func|. + * + * Returns false if the iteration was short-circuited, that is if + * an invocation of |foreach_func| returned false. + * + * Before using this function, you MUST verify |image_data| with + * avb_vbmeta_image_verify() and reject it unless it's signed by a known + * good public key. Additionally, |image_data| must be word-aligned. + */ +bool avb_descriptor_foreach(const uint8_t* image_data, size_t image_size, + AvbDescriptorForeachFunc foreach_func, + void* user_data); + +/* Gets all descriptors in a vbmeta image. + * + * The return value is a NULL-pointer terminated array of + * AvbDescriptor pointers. Free with avb_free() when you are done with + * it. If |out_num_descriptors| is non-NULL, the number of descriptors + * will be returned there. + * + * Note that each AvbDescriptor pointer in the array points into + * |image_data| - all fields need to be byteswapped! + * + * Before using this function, you MUST verify |image_data| with + * avb_vbmeta_image_verify() and reject it unless it's signed by a known + * good public key. Additionally, |image_data| must be word-aligned. + */ +const AvbDescriptor** avb_descriptor_get_all( + const uint8_t* image_data, size_t image_size, + size_t* out_num_descriptors) AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_DESCRIPTOR_H_ */ diff --git a/lib/avb/libavb/avb_footer.c b/lib/avb/libavb/avb_footer.c new file mode 100644 index 0000000..5f6ed71 --- /dev/null +++ b/lib/avb/libavb/avb_footer.c @@ -0,0 +1,54 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_footer.h" +#include "avb_util.h" + +bool avb_footer_validate_and_byteswap(const AvbFooter* src, AvbFooter* dest) { + avb_memcpy(dest, src, sizeof(AvbFooter)); + + dest->version_major = avb_be32toh(dest->version_major); + dest->version_minor = avb_be32toh(dest->version_minor); + + dest->original_image_size = avb_be64toh(dest->original_image_size); + dest->vbmeta_offset = avb_be64toh(dest->vbmeta_offset); + dest->vbmeta_size = avb_be64toh(dest->vbmeta_size); + + /* Check that magic is correct. */ + if (avb_safe_memcmp(dest->magic, AVB_FOOTER_MAGIC, AVB_FOOTER_MAGIC_LEN) != + 0) { + avb_error("Footer magic is incorrect.\n"); + return false; + } + + /* Ensure we don't attempt to access any fields if the footer major + * version is not supported. + */ + if (dest->version_major > AVB_FOOTER_MAJOR_VERSION) { + avb_error("No support for footer version.\n"); + return false; + } + + return true; +} diff --git a/lib/avb/libavb/avb_footer.h b/lib/avb/libavb/avb_footer.h new file mode 100644 index 0000000..6607c75 --- /dev/null +++ b/lib/avb/libavb/avb_footer.h @@ -0,0 +1,86 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_FOOTER_H_ +#define AVB_FOOTER_H_ + +#include "avb_sysdeps.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* Magic for the footer. */ +#define AVB_FOOTER_MAGIC "AVBf" +#define AVB_FOOTER_MAGIC_LEN 4 + +/* Size of the footer. */ +#define AVB_FOOTER_SIZE 64 + +/* The current MAJOR and MINOR versions used - keep in sync with avbtool. */ +#define AVB_FOOTER_MAJOR_VERSION 1 +#define AVB_FOOTER_MINOR_VERSION 0 + +/* The struct used as a footer used on partitions, used to find the + * AvbVBMetaImageHeader struct. This struct is always stored at the + * end of a partition. + */ +typedef struct AvbFooter { + /* 0: Four bytes equal to "AVBf" (AVB_FOOTER_MAGIC). */ + uint8_t magic[AVB_FOOTER_MAGIC_LEN]; + /* 4: The major version of the footer struct. */ + uint32_t version_major; + /* 8: The minor version of the footer struct. */ + uint32_t version_minor; + + /* 12: The original size of the image on the partition. */ + uint64_t original_image_size; + + /* 20: The offset of the |AvbVBMetaImageHeader| struct. */ + uint64_t vbmeta_offset; + + /* 28: The size of the vbmeta block (header + auth + aux blocks). */ + uint64_t vbmeta_size; + + /* 36: Padding to ensure struct is size AVB_FOOTER_SIZE bytes. This + * must be set to zeroes. + */ + uint8_t reserved[28]; +} AVB_ATTR_PACKED AvbFooter; + +/* Copies |src| to |dest| and validates, byte-swapping fields in the + * process if needed. Returns true if valid, false if invalid. + */ +bool avb_footer_validate_and_byteswap(const AvbFooter* src, AvbFooter* dest) + AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_FOOTER_H_ */ diff --git a/lib/avb/libavb/avb_hash_descriptor.c b/lib/avb/libavb/avb_hash_descriptor.c new file mode 100644 index 0000000..2e427de --- /dev/null +++ b/lib/avb/libavb/avb_hash_descriptor.c @@ -0,0 +1,61 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_hash_descriptor.h" +#include "avb_util.h" + +bool avb_hash_descriptor_validate_and_byteswap(const AvbHashDescriptor* src, + AvbHashDescriptor* dest) { + uint64_t expected_size; + + avb_memcpy(dest, src, sizeof(AvbHashDescriptor)); + + if (!avb_descriptor_validate_and_byteswap((const AvbDescriptor*)src, + (AvbDescriptor*)dest)) + return false; + + if (dest->parent_descriptor.tag != AVB_DESCRIPTOR_TAG_HASH) { + avb_error("Invalid tag for hash descriptor.\n"); + return false; + } + + dest->image_size = avb_be64toh(dest->image_size); + dest->partition_name_len = avb_be32toh(dest->partition_name_len); + dest->salt_len = avb_be32toh(dest->salt_len); + dest->digest_len = avb_be32toh(dest->digest_len); + + /* Check that partition_name, salt, and digest are fully contained. */ + expected_size = sizeof(AvbHashDescriptor) - sizeof(AvbDescriptor); + if (!avb_safe_add_to(&expected_size, dest->partition_name_len) || + !avb_safe_add_to(&expected_size, dest->salt_len) || + !avb_safe_add_to(&expected_size, dest->digest_len)) { + avb_error("Overflow while adding up sizes.\n"); + return false; + } + if (expected_size > dest->parent_descriptor.num_bytes_following) { + avb_error("Descriptor payload size overflow.\n"); + return false; + } + return true; +} diff --git a/lib/avb/libavb/avb_hash_descriptor.h b/lib/avb/libavb/avb_hash_descriptor.h new file mode 100644 index 0000000..2668118 --- /dev/null +++ b/lib/avb/libavb/avb_hash_descriptor.h @@ -0,0 +1,73 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_HASH_DESCRIPTOR_H_ +#define AVB_HASH_DESCRIPTOR_H_ + +#include "avb_descriptor.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* A descriptor containing information about hash for an image. + * + * This descriptor is typically used for boot partitions to verify the + * entire kernel+initramfs image before executing it. + * + * Following this struct are |partition_name_len| bytes of the + * partition name (UTF-8 encoded), |salt_len| bytes of salt, and then + * |digest_len| bytes of the digest. + * + * The |reserved| field is for future expansion and must be set to NUL + * bytes. + */ +typedef struct AvbHashDescriptor { + AvbDescriptor parent_descriptor; + uint64_t image_size; + uint8_t hash_algorithm[32]; + uint32_t partition_name_len; + uint32_t salt_len; + uint32_t digest_len; + uint8_t reserved[64]; +} AVB_ATTR_PACKED AvbHashDescriptor; + +/* Copies |src| to |dest| and validates, byte-swapping fields in the + * process if needed. Returns true if valid, false if invalid. + * + * Data following the struct is not validated nor copied. + */ +bool avb_hash_descriptor_validate_and_byteswap(const AvbHashDescriptor* src, + AvbHashDescriptor* dest) + AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_HASH_DESCRIPTOR_H_ */ diff --git a/lib/avb/libavb/avb_hashtree_descriptor.c b/lib/avb/libavb/avb_hashtree_descriptor.c new file mode 100644 index 0000000..b961e47 --- /dev/null +++ b/lib/avb/libavb/avb_hashtree_descriptor.c @@ -0,0 +1,69 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_hashtree_descriptor.h" +#include "avb_util.h" + +bool avb_hashtree_descriptor_validate_and_byteswap( + const AvbHashtreeDescriptor* src, AvbHashtreeDescriptor* dest) { + uint64_t expected_size; + + avb_memcpy(dest, src, sizeof(AvbHashtreeDescriptor)); + + if (!avb_descriptor_validate_and_byteswap((const AvbDescriptor*)src, + (AvbDescriptor*)dest)) + return false; + + if (dest->parent_descriptor.tag != AVB_DESCRIPTOR_TAG_HASHTREE) { + avb_error("Invalid tag for hashtree descriptor.\n"); + return false; + } + + dest->dm_verity_version = avb_be32toh(dest->dm_verity_version); + dest->image_size = avb_be64toh(dest->image_size); + dest->tree_offset = avb_be64toh(dest->tree_offset); + dest->tree_size = avb_be64toh(dest->tree_size); + dest->data_block_size = avb_be32toh(dest->data_block_size); + dest->hash_block_size = avb_be32toh(dest->hash_block_size); + dest->fec_num_roots = avb_be32toh(dest->fec_num_roots); + dest->fec_offset = avb_be64toh(dest->fec_offset); + dest->fec_size = avb_be64toh(dest->fec_size); + dest->partition_name_len = avb_be32toh(dest->partition_name_len); + dest->salt_len = avb_be32toh(dest->salt_len); + dest->root_digest_len = avb_be32toh(dest->root_digest_len); + + /* Check that partition_name, salt, and root_digest are fully contained. */ + expected_size = sizeof(AvbHashtreeDescriptor) - sizeof(AvbDescriptor); + if (!avb_safe_add_to(&expected_size, dest->partition_name_len) || + !avb_safe_add_to(&expected_size, dest->salt_len) || + !avb_safe_add_to(&expected_size, dest->root_digest_len)) { + avb_error("Overflow while adding up sizes.\n"); + return false; + } + if (expected_size > dest->parent_descriptor.num_bytes_following) { + avb_error("Descriptor payload size overflow.\n"); + return false; + } + return true; +} diff --git a/lib/avb/libavb/avb_hashtree_descriptor.h b/lib/avb/libavb/avb_hashtree_descriptor.h new file mode 100644 index 0000000..a5aafbf --- /dev/null +++ b/lib/avb/libavb/avb_hashtree_descriptor.h @@ -0,0 +1,83 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_HASHTREE_DESCRIPTOR_H_ +#define AVB_HASHTREE_DESCRIPTOR_H_ + +#include "avb_descriptor.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* A descriptor containing information about a dm-verity hashtree. + * + * Hash-trees are used to verify large partitions typically containing + * file systems. See + * https://gitlab.com/cryptsetup/cryptsetup/wikis/DMVerity for more + * information about dm-verity. + * + * Following this struct are |partition_name_len| bytes of the + * partition name (UTF-8 encoded), |salt_len| bytes of salt, and then + * |root_digest_len| bytes of the root digest. + * + * The |reserved| field is for future expansion and must be set to NUL + * bytes. + */ +typedef struct AvbHashtreeDescriptor { + AvbDescriptor parent_descriptor; + uint32_t dm_verity_version; + uint64_t image_size; + uint64_t tree_offset; + uint64_t tree_size; + uint32_t data_block_size; + uint32_t hash_block_size; + uint32_t fec_num_roots; + uint64_t fec_offset; + uint64_t fec_size; + uint8_t hash_algorithm[32]; + uint32_t partition_name_len; + uint32_t salt_len; + uint32_t root_digest_len; + uint8_t reserved[64]; +} AVB_ATTR_PACKED AvbHashtreeDescriptor; + +/* Copies |src| to |dest| and validates, byte-swapping fields in the + * process if needed. Returns true if valid, false if invalid. + * + * Data following the struct is not validated nor copied. + */ +bool avb_hashtree_descriptor_validate_and_byteswap( + const AvbHashtreeDescriptor* src, + AvbHashtreeDescriptor* dest) AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_HASHTREE_DESCRIPTOR_H_ */ diff --git a/lib/avb/libavb/avb_kernel_cmdline_descriptor.c b/lib/avb/libavb/avb_kernel_cmdline_descriptor.c new file mode 100644 index 0000000..24b2978 --- /dev/null +++ b/lib/avb/libavb/avb_kernel_cmdline_descriptor.c @@ -0,0 +1,57 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_kernel_cmdline_descriptor.h" +#include "avb_util.h" + +bool avb_kernel_cmdline_descriptor_validate_and_byteswap( + const AvbKernelCmdlineDescriptor* src, AvbKernelCmdlineDescriptor* dest) { + uint64_t expected_size; + + avb_memcpy(dest, src, sizeof(AvbKernelCmdlineDescriptor)); + + if (!avb_descriptor_validate_and_byteswap((const AvbDescriptor*)src, + (AvbDescriptor*)dest)) + return false; + + if (dest->parent_descriptor.tag != AVB_DESCRIPTOR_TAG_KERNEL_CMDLINE) { + avb_error("Invalid tag for kernel cmdline descriptor.\n"); + return false; + } + + dest->kernel_cmdline_length = avb_be32toh(dest->kernel_cmdline_length); + + /* Check that kernel_cmdline is fully contained. */ + expected_size = sizeof(AvbKernelCmdlineDescriptor) - sizeof(AvbDescriptor); + if (!avb_safe_add_to(&expected_size, dest->kernel_cmdline_length)) { + avb_error("Overflow while adding up sizes.\n"); + return false; + } + if (expected_size > dest->parent_descriptor.num_bytes_following) { + avb_error("Descriptor payload size overflow.\n"); + return false; + } + + return true; +} diff --git a/lib/avb/libavb/avb_kernel_cmdline_descriptor.h b/lib/avb/libavb/avb_kernel_cmdline_descriptor.h new file mode 100644 index 0000000..0eece7d --- /dev/null +++ b/lib/avb/libavb/avb_kernel_cmdline_descriptor.h @@ -0,0 +1,62 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_KERNEL_CMDLINE_DESCRIPTOR_H_ +#define AVB_KERNEL_CMDLINE_DESCRIPTOR_H_ + +#include "avb_descriptor.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* A descriptor containing information to be appended to the kernel + * command-line. + * + * Following this struct are |kernel_cmdline_len| bytes with the + * kernel command-line (UTF-8 encoded). + */ +typedef struct AvbKernelCmdlineDescriptor { + AvbDescriptor parent_descriptor; + uint32_t kernel_cmdline_length; +} AVB_ATTR_PACKED AvbKernelCmdlineDescriptor; + +/* Copies |src| to |dest| and validates, byte-swapping fields in the + * process if needed. Returns true if valid, false if invalid. + * + * Data following the struct is not validated nor copied. + */ +bool avb_kernel_cmdline_descriptor_validate_and_byteswap( + const AvbKernelCmdlineDescriptor* src, + AvbKernelCmdlineDescriptor* dest) AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_KERNEL_CMDLINE_DESCRIPTOR_H_ */ diff --git a/lib/avb/libavb/avb_ops.h b/lib/avb/libavb/avb_ops.h new file mode 100644 index 0000000..30309c5 --- /dev/null +++ b/lib/avb/libavb/avb_ops.h @@ -0,0 +1,177 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_OPS_H_ +#define AVB_OPS_H_ + +#include "avb_sysdeps.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* Return codes used for I/O operations. + * + * AVB_IO_RESULT_OK is returned if the requested operation was + * successful. + * + * AVB_IO_RESULT_ERROR_IO is returned if the underlying hardware (disk + * or other subsystem) encountered an I/O error. + * + * AVB_IO_RESULT_ERROR_OOM is returned if unable to allocate memory. + * + * AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION is returned if the requested + * partition does not exist. + * + * AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION is returned if the + * range of bytes requested to be read or written is outside the range + * of the partition. + */ +typedef enum { + AVB_IO_RESULT_OK, + AVB_IO_RESULT_ERROR_OOM, + AVB_IO_RESULT_ERROR_IO, + AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION, + AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION +} AvbIOResult; + +struct AvbOps; +typedef struct AvbOps AvbOps; + +struct AvbABData; + +/* High-level operations/functions/methods that are platform + * dependent. + */ +struct AvbOps { + /* Reads |num_bytes| from offset |offset| from partition with name + * |partition| (NUL-terminated UTF-8 string). If |offset| is + * negative, its absolute value should be interpreted as the number + * of bytes from the end of the partition. + * + * This function returns AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION if + * there is no partition with the given name, + * AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION if the requested + * |offset| is outside the partition, and AVB_IO_RESULT_ERROR_IO if + * there was an I/O error from the underlying I/O subsystem. If the + * operation succeeds as requested AVB_IO_RESULT_OK is returned and + * the data is available in |buffer|. + * + * The only time partial I/O may occur is if reading beyond the end + * of the partition. In this case the value returned in + * |out_num_read| may be smaller than |num_bytes|. + */ + AvbIOResult (*read_from_partition)(AvbOps* ops, const char* partition, + int64_t offset, size_t num_bytes, + void* buffer, size_t* out_num_read); + + /* Writes |num_bytes| from |bffer| at offset |offset| to partition + * with name |partition| (NUL-terminated UTF-8 string). If |offset| + * is negative, its absolute value should be interpreted as the + * number of bytes from the end of the partition. + * + * This function returns AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION if + * there is no partition with the given name, + * AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION if the requested + * byterange goes outside the partition, and AVB_IO_RESULT_ERROR_IO + * if there was an I/O error from the underlying I/O subsystem. If + * the operation succeeds as requested AVB_IO_RESULT_OK is + * returned. + * + * This function never does any partial I/O, it either transfers all + * of the requested bytes or returns an error. + */ + AvbIOResult (*write_to_partition)(AvbOps* ops, const char* partition, + int64_t offset, size_t num_bytes, + const void* buffer); + + /* Checks if the given public key used to sign the 'vbmeta' + * partition is trusted. Boot loaders typically compare this with + * embedded key material generated with 'avbtool + * extract_public_key'. + * + * If AVB_IO_RESULT_OK is returned then |out_is_trusted| is set - + * true if trusted or false if untrusted. + */ + AvbIOResult (*validate_vbmeta_public_key)(AvbOps* ops, + const uint8_t* public_key_data, + size_t public_key_length, + bool* out_is_trusted); + + /* Gets the rollback index corresponding to the slot given by + * |rollback_index_slot|. The value is returned in + * |out_rollback_index|. Returns AVB_IO_RESULT_OK if the rollback + * index was retrieved, otherwise an error code. + * + * A device may have a limited amount of rollback index slots (say, + * one or four) so may error out if |rollback_index_slot| exceeds + * this number. + */ + AvbIOResult (*read_rollback_index)(AvbOps* ops, size_t rollback_index_slot, + uint64_t* out_rollback_index); + + /* Sets the rollback index corresponding to the slot given by + * |rollback_index_slot| to |rollback_index|. Returns + * AVB_IO_RESULT_OK if the rollback index was set, otherwise an + * error code. + * + * A device may have a limited amount of rollback index slots (say, + * one or four) so may error out if |rollback_index_slot| exceeds + * this number. + */ + AvbIOResult (*write_rollback_index)(AvbOps* ops, size_t rollback_index_slot, + uint64_t rollback_index); + + /* Gets whether the device is unlocked. The value is returned in + * |out_is_unlocked| (true if unlocked, false otherwise). Returns + * AVB_IO_RESULT_OK if the state was retrieved, otherwise an error + * code. + */ + AvbIOResult (*read_is_device_unlocked)(AvbOps* ops, bool* out_is_unlocked); + + /* Gets the unique partition GUID for a partition with name in + * |partition| (NUL-terminated UTF-8 string). The GUID is copied as + * a string into |guid_buf| of size |guid_buf_size| and will be NUL + * terminated. The string must be lower-case and properly + * hyphenated. For example: + * + * 527c1c6d-6361-4593-8842-3c78fcd39219 + * + * Returns AVB_IO_RESULT_OK on success, otherwise an error code. + */ + AvbIOResult (*get_unique_guid_for_partition)(AvbOps* ops, + const char* partition, + char* guid_buf, + size_t guid_buf_size); +}; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_OPS_H_ */ diff --git a/lib/avb/libavb/avb_property_descriptor.c b/lib/avb/libavb/avb_property_descriptor.c new file mode 100644 index 0000000..03d8315 --- /dev/null +++ b/lib/avb/libavb/avb_property_descriptor.c @@ -0,0 +1,167 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_property_descriptor.h" +#include "avb_util.h" + +bool avb_property_descriptor_validate_and_byteswap( + const AvbPropertyDescriptor* src, AvbPropertyDescriptor* dest) { + uint64_t expected_size; + + avb_memcpy(dest, src, sizeof(AvbPropertyDescriptor)); + + if (!avb_descriptor_validate_and_byteswap((const AvbDescriptor*)src, + (AvbDescriptor*)dest)) + return false; + + if (dest->parent_descriptor.tag != AVB_DESCRIPTOR_TAG_PROPERTY) { + avb_error("Invalid tag for property descriptor.\n"); + return false; + } + + dest->key_num_bytes = avb_be64toh(dest->key_num_bytes); + dest->value_num_bytes = avb_be64toh(dest->value_num_bytes); + + /* Check that key and value are fully contained. */ + expected_size = sizeof(AvbPropertyDescriptor) - sizeof(AvbDescriptor) + 2; + if (!avb_safe_add_to(&expected_size, dest->key_num_bytes) || + !avb_safe_add_to(&expected_size, dest->value_num_bytes)) { + avb_error("Overflow while adding up sizes.\n"); + return false; + } + if (expected_size > dest->parent_descriptor.num_bytes_following) { + avb_error("Descriptor payload size overflow.\n"); + return false; + } + + return true; +} + +typedef struct { + const char* key; + size_t key_size; + const char* ret_value; + size_t ret_value_size; +} PropertyIteratorData; + +static bool property_lookup_desc_foreach(const AvbDescriptor* header, + void* user_data) { + PropertyIteratorData* data = (PropertyIteratorData*)user_data; + AvbPropertyDescriptor prop_desc; + const uint8_t* p; + bool ret = true; + + if (header->tag != AVB_DESCRIPTOR_TAG_PROPERTY) goto out; + + if (!avb_property_descriptor_validate_and_byteswap( + (const AvbPropertyDescriptor*)header, &prop_desc)) + goto out; + + p = (const uint8_t*)header; + if (p[sizeof(AvbPropertyDescriptor) + prop_desc.key_num_bytes] != 0) { + avb_error("No terminating NUL byte in key.\n"); + goto out; + } + + if (data->key_size == prop_desc.key_num_bytes) { + if (avb_memcmp(p + sizeof(AvbPropertyDescriptor), data->key, + data->key_size) == 0) { + data->ret_value = (const char*)(p + sizeof(AvbPropertyDescriptor) + + prop_desc.key_num_bytes + 1); + data->ret_value_size = prop_desc.value_num_bytes; + /* Stop iterating. */ + ret = false; + goto out; + } + } + +out: + return ret; +} + +const char* avb_property_lookup(const uint8_t* image_data, size_t image_size, + const char* key, size_t key_size, + size_t* out_value_size) { + PropertyIteratorData data; + + if (key_size == 0) key_size = avb_strlen(key); + + data.key = key; + data.key_size = key_size; + + if (avb_descriptor_foreach(image_data, image_size, + property_lookup_desc_foreach, &data) == 0) { + if (out_value_size != NULL) *out_value_size = data.ret_value_size; + return data.ret_value; + } + + if (out_value_size != NULL) *out_value_size = 0; + return NULL; +} + +bool avb_property_lookup_uint64(const uint8_t* image_data, size_t image_size, + const char* key, size_t key_size, + uint64_t* out_value) { + const char* value; + bool ret = false; + uint64_t parsed_val; + int base; + int n; + + value = avb_property_lookup(image_data, image_size, key, key_size, NULL); + if (value == NULL) goto out; + + base = 10; + if (avb_memcmp(value, "0x", 2) == 0) { + base = 16; + value += 2; + } + + parsed_val = 0; + for (n = 0; value[n] != '\0'; n++) { + int c = value[n]; + int digit; + + parsed_val *= base; + + if (c >= '0' && c <= '9') { + digit = c - '0'; + } else if (base == 16 && c >= 'a' && c <= 'f') { + digit = c - 'a' + 10; + } else if (base == 16 && c >= 'A' && c <= 'F') { + digit = c - 'A' + 10; + } else { + avb_error("Invalid digit.\n"); + goto out; + } + + parsed_val += digit; + } + + ret = true; + if (out_value != NULL) *out_value = parsed_val; + +out: + return ret; +} diff --git a/lib/avb/libavb/avb_property_descriptor.h b/lib/avb/libavb/avb_property_descriptor.h new file mode 100644 index 0000000..2ad1c2e --- /dev/null +++ b/lib/avb/libavb/avb_property_descriptor.h @@ -0,0 +1,101 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_PROPERTY_DESCRIPTOR_H_ +#define AVB_PROPERTY_DESCRIPTOR_H_ + +#include "avb_descriptor.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* A descriptor for properties (free-form key/value pairs). + * + * Following this struct are |key_num_bytes| bytes of key data, + * followed by a NUL byte, then |value_num_bytes| bytes of value data, + * followed by a NUL byte and then enough padding to make the combined + * size a multiple of 8. + */ +typedef struct AvbPropertyDescriptor { + AvbDescriptor parent_descriptor; + uint64_t key_num_bytes; + uint64_t value_num_bytes; +} AVB_ATTR_PACKED AvbPropertyDescriptor; + +/* Copies |src| to |dest| and validates, byte-swapping fields in the + * process if needed. Returns true if valid, false if invalid. + * + * Data following the struct is not validated nor copied. + */ +bool avb_property_descriptor_validate_and_byteswap( + const AvbPropertyDescriptor* src, + AvbPropertyDescriptor* dest) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Convenience function for looking up the value for a property with + * name |key| in a vbmeta image. If |key_size| is 0, |key| must be + * NUL-terminated. + * + * The |image_data| parameter must be a pointer to a vbmeta image of + * size |image_size|. + * + * This function returns a pointer to the value inside the passed-in + * image or NULL if not found. Note that the value is always + * guaranteed to be followed by a NUL byte. + * + * If the value was found and |out_value_size| is not NULL, the size + * of the value is returned there. + * + * This function is O(n) in number of descriptors so if you need to + * look up a lot of values, you may want to build a more efficient + * lookup-table by manually walking all descriptors using + * avb_descriptor_foreach(). + * + * Before using this function, you MUST verify |image_data| with + * avb_vbmeta_image_verify() and reject it unless it's signed by a + * known good public key. + */ +const char* avb_property_lookup( + const uint8_t* image_data, size_t image_size, const char* key, + size_t key_size, size_t* out_value_size) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Like avb_property_lookup() but parses the intial portions of the + * value as an unsigned 64-bit integer. Both decimal and hexadecimal + * representations (e.g. "0x2a") are supported. Returns false on + * failure and true on success. On success, the parsed value is + * returned in |out_value|. + */ +bool avb_property_lookup_uint64( + const uint8_t* image_data, size_t image_size, const char* key, + size_t key_size, uint64_t* out_value) AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_PROPERTY_DESCRIPTOR_H_ */ diff --git a/lib/avb/libavb/avb_rsa.c b/lib/avb/libavb/avb_rsa.c new file mode 100644 index 0000000..8a2b8b4 --- /dev/null +++ b/lib/avb/libavb/avb_rsa.c @@ -0,0 +1,271 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +/* Copyright (c) 2011 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +/* Implementation of RSA signature verification which uses a pre-processed + * key for computation. The code extends libmincrypt RSA verification code to + * support multiple RSA key lengths and hash digest algorithms. + */ + +#include "avb_rsa.h" +#include "avb_sha.h" +#include "avb_util.h" +#include "avb_vbmeta_image.h" + +typedef struct Key { + unsigned int len; /* Length of n[] in number of uint32_t */ + uint32_t n0inv; /* -1 / n[0] mod 2^32 */ + uint32_t* n; /* modulus as array (host-byte order) */ + uint32_t* rr; /* R^2 as array (host-byte order) */ +} Key; + +Key* parse_key_data(const uint8_t* data, size_t length) { + AvbRSAPublicKeyHeader h; + Key* key = NULL; + size_t expected_length; + unsigned int i; + const uint8_t* n; + const uint8_t* rr; + + if (!avb_rsa_public_key_header_validate_and_byteswap( + (const AvbRSAPublicKeyHeader*)data, &h)) { + avb_error("Invalid key.\n"); + goto fail; + } + + if (!(h.key_num_bits == 2048 || h.key_num_bits == 4096 || + h.key_num_bits == 8192)) { + avb_error("Unexpected key length.\n"); + goto fail; + } + + expected_length = sizeof(AvbRSAPublicKeyHeader) + 2 * h.key_num_bits / 8; + if (length != expected_length) { + avb_error("Key does not match expected length.\n"); + goto fail; + } + + n = data + sizeof(AvbRSAPublicKeyHeader); + rr = data + sizeof(AvbRSAPublicKeyHeader) + h.key_num_bits / 8; + + /* Store n and rr following the key header so we only have to do one + * allocation. + */ + key = (Key*)(avb_malloc(sizeof(Key) + 2 * h.key_num_bits / 8)); + if (key == NULL) goto fail; + + key->len = h.key_num_bits / 32; + key->n0inv = h.n0inv; + key->n = (uint32_t*)(key + 1); /* Skip ahead sizeof(Key) bytes. */ + key->rr = key->n + key->len; + + /* Crypto-code below (modpowF4() and friends) expects the key in + * little-endian format (rather than the format we're storing the + * key in), so convert it. + */ + for (i = 0; i < key->len; i++) { + key->n[i] = avb_be32toh(((uint32_t*)n)[key->len - i - 1]); + key->rr[i] = avb_be32toh(((uint32_t*)rr)[key->len - i - 1]); + } + return key; + +fail: + if (key != NULL) avb_free(key); + return NULL; +} + +void free_parsed_key(Key* key) { avb_free(key); } + +/* a[] -= mod */ +static void subM(const Key* key, uint32_t* a) { + int64_t A = 0; + uint32_t i; + for (i = 0; i < key->len; ++i) { + A += (uint64_t)a[i] - key->n[i]; + a[i] = (uint32_t)A; + A >>= 32; + } +} + +/* return a[] >= mod */ +static int geM(const Key* key, uint32_t* a) { + uint32_t i; + for (i = key->len; i;) { + --i; + if (a[i] < key->n[i]) return 0; + if (a[i] > key->n[i]) return 1; + } + return 1; /* equal */ +} + +/* montgomery c[] += a * b[] / R % mod */ +static void montMulAdd(const Key* key, uint32_t* c, const uint32_t a, + const uint32_t* b) { + uint64_t A = (uint64_t)a * b[0] + c[0]; + uint32_t d0 = (uint32_t)A * key->n0inv; + uint64_t B = (uint64_t)d0 * key->n[0] + (uint32_t)A; + uint32_t i; + + for (i = 1; i < key->len; ++i) { + A = (A >> 32) + (uint64_t)a * b[i] + c[i]; + B = (B >> 32) + (uint64_t)d0 * key->n[i] + (uint32_t)A; + c[i - 1] = (uint32_t)B; + } + + A = (A >> 32) + (B >> 32); + + c[i - 1] = (uint32_t)A; + + if (A >> 32) { + subM(key, c); + } +} + +/* montgomery c[] = a[] * b[] / R % mod */ +static void montMul(const Key* key, uint32_t* c, uint32_t* a, uint32_t* b) { + uint32_t i; + for (i = 0; i < key->len; ++i) { + c[i] = 0; + } + for (i = 0; i < key->len; ++i) { + montMulAdd(key, c, a[i], b); + } +} + +/* In-place public exponentiation. (65537} + * Input and output big-endian byte array in inout. + */ +static void modpowF4(const Key* key, uint8_t* inout) { + uint32_t* a = (uint32_t*)avb_malloc(key->len * sizeof(uint32_t)); + uint32_t* aR = (uint32_t*)avb_malloc(key->len * sizeof(uint32_t)); + uint32_t* aaR = (uint32_t*)avb_malloc(key->len * sizeof(uint32_t)); + if (a == NULL || aR == NULL || aaR == NULL) goto out; + + uint32_t* aaa = aaR; /* Re-use location. */ + int i; + + /* Convert from big endian byte array to little endian word array. */ + for (i = 0; i < (int)key->len; ++i) { + uint32_t tmp = (inout[((key->len - 1 - i) * 4) + 0] << 24) | + (inout[((key->len - 1 - i) * 4) + 1] << 16) | + (inout[((key->len - 1 - i) * 4) + 2] << 8) | + (inout[((key->len - 1 - i) * 4) + 3] << 0); + a[i] = tmp; + } + + montMul(key, aR, a, key->rr); /* aR = a * RR / R mod M */ + for (i = 0; i < 16; i += 2) { + montMul(key, aaR, aR, aR); /* aaR = aR * aR / R mod M */ + montMul(key, aR, aaR, aaR); /* aR = aaR * aaR / R mod M */ + } + montMul(key, aaa, aR, a); /* aaa = aR * a / R mod M */ + + /* Make sure aaa < mod; aaa is at most 1x mod too large. */ + if (geM(key, aaa)) { + subM(key, aaa); + } + + /* Convert to bigendian byte array */ + for (i = (int)key->len - 1; i >= 0; --i) { + uint32_t tmp = aaa[i]; + *inout++ = (uint8_t)(tmp >> 24); + *inout++ = (uint8_t)(tmp >> 16); + *inout++ = (uint8_t)(tmp >> 8); + *inout++ = (uint8_t)(tmp >> 0); + } + +out: + if (a != NULL) avb_free(a); + if (aR != NULL) avb_free(aR); + if (aaR != NULL) avb_free(aaR); +} + +/* Verify a RSA PKCS1.5 signature against an expected hash. + * Returns false on failure, true on success. + */ +bool avb_rsa_verify(const uint8_t* key, size_t key_num_bytes, + const uint8_t* sig, size_t sig_num_bytes, + const uint8_t* hash, size_t hash_num_bytes, + const uint8_t* padding, size_t padding_num_bytes) { + uint8_t* buf = NULL; + Key* parsed_key = NULL; + bool success = false; + + if (key == NULL || sig == NULL || hash == NULL || padding == NULL) { + avb_error("Invalid input.\n"); + goto out; + } + + parsed_key = parse_key_data(key, key_num_bytes); + if (parsed_key == NULL) { + avb_error("Error parsing key.\n"); + goto out; + } + + if (sig_num_bytes != (parsed_key->len * sizeof(uint32_t))) { + avb_error("Signature length does not match key length.\n"); + goto out; + } + + if (padding_num_bytes != sig_num_bytes - hash_num_bytes) { + avb_error("Padding length does not match hash and signature lengths.\n"); + goto out; + } + + buf = (uint8_t*)avb_malloc(sig_num_bytes); + if (buf == NULL) { + avb_error("Error allocating memory.\n"); + goto out; + } + avb_memcpy(buf, sig, sig_num_bytes); + + modpowF4(parsed_key, buf); + + /* Check padding bytes. + * + * Even though there are probably no timing issues here, we use + * avb_safe_memcmp() just to be on the safe side. + */ + if (avb_safe_memcmp(buf, padding, padding_num_bytes)) { + avb_error("Padding check failed.\n"); + goto out; + } + + /* Check hash. */ + if (avb_safe_memcmp(buf + padding_num_bytes, hash, hash_num_bytes)) { + avb_error("Hash check failed.\n"); + goto out; + } + + success = true; + +out: + if (parsed_key != NULL) free_parsed_key(parsed_key); + if (buf != NULL) avb_free(buf); + return success; +} diff --git a/lib/avb/libavb/avb_rsa.h b/lib/avb/libavb/avb_rsa.h new file mode 100644 index 0000000..e82102b --- /dev/null +++ b/lib/avb/libavb/avb_rsa.h @@ -0,0 +1,78 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +/* Copyright (c) 2011 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +#ifdef AVB_INSIDE_LIBAVB_H +#error "You can't include avb_rsa.h in the public header libavb.h." +#endif + +#ifndef AVB_COMPILATION +#error "Never include this file, it may only be used from internal avb code." +#endif + +#ifndef AVB_RSA_H_ +#define AVB_RSA_H_ + +#ifdef __cplusplus +extern "C" { +#endif + +#include "avb_sysdeps.h" + +/* Size of a RSA-2048 signature. */ +#define AVB_RSA2048_NUM_BYTES 256 + +/* Size of a RSA-4096 signature. */ +#define AVB_RSA4096_NUM_BYTES 512 + +/* Size of a RSA-8192 signature. */ +#define AVB_RSA8192_NUM_BYTES 1024 + +/* Using the key given by |key|, verify a RSA signature |sig| of + * length |sig_num_bytes| against an expected |hash| of length + * |hash_num_bytes|. The padding to expect must be passed in using + * |padding| of length |padding_num_bytes|. + * + * The data in |key| must match the format defined in + * |AvbRSAPublicKeyHeader|, including the two large numbers + * following. The |key_num_bytes| must be the size of the entire + * serialized key. + * + * Returns false if verification fails, true otherwise. + */ +bool avb_rsa_verify(const uint8_t* key, size_t key_num_bytes, + const uint8_t* sig, size_t sig_num_bytes, + const uint8_t* hash, size_t hash_num_bytes, + const uint8_t* padding, + size_t padding_num_bytes) AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_RSA_H_ */ diff --git a/lib/avb/libavb/avb_sha.h b/lib/avb/libavb/avb_sha.h new file mode 100644 index 0000000..b925bd2 --- /dev/null +++ b/lib/avb/libavb/avb_sha.h @@ -0,0 +1,94 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#ifdef AVB_INSIDE_LIBAVB_H +#error "You can't include avb_sha.h in the public header libavb.h." +#endif + +#ifndef AVB_COMPILATION +#error "Never include this file, it may only be used from internal avb code." +#endif + +#ifndef AVB_SHA_H_ +#define AVB_SHA_H_ + +#ifdef __cplusplus +extern "C" { +#endif + +#include "avb_sysdeps.h" + +/* Size in bytes of a SHA-256 digest. */ +#define AVB_SHA256_DIGEST_SIZE 32 + +/* Block size in bytes of a SHA-256 digest. */ +#define AVB_SHA256_BLOCK_SIZE 64 + +/* Size in bytes of a SHA-512 digest. */ +#define AVB_SHA512_DIGEST_SIZE 64 + +/* Block size in bytes of a SHA-512 digest. */ +#define AVB_SHA512_BLOCK_SIZE 128 + +/* Data structure used for SHA-256. */ +typedef struct { + uint32_t h[8]; + uint32_t tot_len; + uint32_t len; + uint8_t block[2 * AVB_SHA256_BLOCK_SIZE]; + uint8_t buf[AVB_SHA256_DIGEST_SIZE]; /* Used for storing the final digest. */ +} AvbSHA256Ctx; + +/* Data structure used for SHA-512. */ +typedef struct { + uint64_t h[8]; + uint32_t tot_len; + uint32_t len; + uint8_t block[2 * AVB_SHA512_BLOCK_SIZE]; + uint8_t buf[AVB_SHA512_DIGEST_SIZE]; /* Used for storing the final digest. */ +} AvbSHA512Ctx; + +/* Initializes the SHA-256 context. */ +void avb_sha256_init(AvbSHA256Ctx* ctx); + +/* Updates the SHA-256 context with |len| bytes from |data|. */ +void avb_sha256_update(AvbSHA256Ctx* ctx, const uint8_t* data, uint32_t len); + +/* Returns the SHA-256 digest. */ +uint8_t* avb_sha256_final(AvbSHA256Ctx* ctx) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Initializes the SHA-512 context. */ +void avb_sha512_init(AvbSHA512Ctx* ctx); + +/* Updates the SHA-512 context with |len| bytes from |data|. */ +void avb_sha512_update(AvbSHA512Ctx* ctx, const uint8_t* data, uint32_t len); + +/* Returns the SHA-512 digest. */ +uint8_t* avb_sha512_final(AvbSHA512Ctx* ctx) AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_SHA_H_ */ diff --git a/lib/avb/libavb/avb_sha256.c b/lib/avb/libavb/avb_sha256.c new file mode 100644 index 0000000..b1748eb --- /dev/null +++ b/lib/avb/libavb/avb_sha256.c @@ -0,0 +1,384 @@ +/* SHA-256 and SHA-512 implementation based on code by Oliver Gay + * <olivier.gay@a3.epfl.ch> under a BSD-style license. See below. + */ + +/* + * FIPS 180-2 SHA-224/256/384/512 implementation + * Last update: 02/02/2007 + * Issue date: 04/30/2005 + * + * Copyright (C) 2005, 2007 Olivier Gay <olivier.gay@a3.epfl.ch> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the project nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include "avb_sha.h" + +#define SHFR(x, n) (x >> n) +#define ROTR(x, n) ((x >> n) | (x << ((sizeof(x) << 3) - n))) +#define ROTL(x, n) ((x << n) | (x >> ((sizeof(x) << 3) - n))) +#define CH(x, y, z) ((x & y) ^ (~x & z)) +#define MAJ(x, y, z) ((x & y) ^ (x & z) ^ (y & z)) + +#define SHA256_F1(x) (ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22)) +#define SHA256_F2(x) (ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25)) +#define SHA256_F3(x) (ROTR(x, 7) ^ ROTR(x, 18) ^ SHFR(x, 3)) +#define SHA256_F4(x) (ROTR(x, 17) ^ ROTR(x, 19) ^ SHFR(x, 10)) + +#define UNPACK32(x, str) \ + { \ + *((str) + 3) = (uint8_t)((x)); \ + *((str) + 2) = (uint8_t)((x) >> 8); \ + *((str) + 1) = (uint8_t)((x) >> 16); \ + *((str) + 0) = (uint8_t)((x) >> 24); \ + } + +#define PACK32(str, x) \ + { \ + *(x) = ((uint32_t) * ((str) + 3)) | ((uint32_t) * ((str) + 2) << 8) | \ + ((uint32_t) * ((str) + 1) << 16) | \ + ((uint32_t) * ((str) + 0) << 24); \ + } + +/* Macros used for loops unrolling */ + +#define SHA256_SCR(i) \ + { w[i] = SHA256_F4(w[i - 2]) + w[i - 7] + SHA256_F3(w[i - 15]) + w[i - 16]; } + +#define SHA256_EXP(a, b, c, d, e, f, g, h, j) \ + { \ + t1 = wv[h] + SHA256_F2(wv[e]) + CH(wv[e], wv[f], wv[g]) + sha256_k[j] + \ + w[j]; \ + t2 = SHA256_F1(wv[a]) + MAJ(wv[a], wv[b], wv[c]); \ + wv[d] += t1; \ + wv[h] = t1 + t2; \ + } + +static const uint32_t sha256_h0[8] = {0x6a09e667, 0xbb67ae85, 0x3c6ef372, + 0xa54ff53a, 0x510e527f, 0x9b05688c, + 0x1f83d9ab, 0x5be0cd19}; + +static const uint32_t sha256_k[64] = { + 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, + 0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, + 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786, + 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da, + 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, + 0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, + 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b, + 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070, + 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, + 0x5b9cca4f, 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, + 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2}; + +/* SHA-256 implementation */ +void avb_sha256_init(AvbSHA256Ctx* ctx) { +#ifndef UNROLL_LOOPS + int i; + for (i = 0; i < 8; i++) { + ctx->h[i] = sha256_h0[i]; + } +#else + ctx->h[0] = sha256_h0[0]; + ctx->h[1] = sha256_h0[1]; + ctx->h[2] = sha256_h0[2]; + ctx->h[3] = sha256_h0[3]; + ctx->h[4] = sha256_h0[4]; + ctx->h[5] = sha256_h0[5]; + ctx->h[6] = sha256_h0[6]; + ctx->h[7] = sha256_h0[7]; +#endif /* !UNROLL_LOOPS */ + + ctx->len = 0; + ctx->tot_len = 0; +} + +static void SHA256_transform(AvbSHA256Ctx* ctx, const uint8_t* message, + unsigned int block_nb) { + uint32_t w[64]; + uint32_t wv[8]; + uint32_t t1, t2; + const unsigned char* sub_block; + int i; + +#ifndef UNROLL_LOOPS + int j; +#endif + + for (i = 0; i < (int)block_nb; i++) { + sub_block = message + (i << 6); + +#ifndef UNROLL_LOOPS + for (j = 0; j < 16; j++) { + PACK32(&sub_block[j << 2], &w[j]); + } + + for (j = 16; j < 64; j++) { + SHA256_SCR(j); + } + + for (j = 0; j < 8; j++) { + wv[j] = ctx->h[j]; + } + + for (j = 0; j < 64; j++) { + t1 = wv[7] + SHA256_F2(wv[4]) + CH(wv[4], wv[5], wv[6]) + sha256_k[j] + + w[j]; + t2 = SHA256_F1(wv[0]) + MAJ(wv[0], wv[1], wv[2]); + wv[7] = wv[6]; + wv[6] = wv[5]; + wv[5] = wv[4]; + wv[4] = wv[3] + t1; + wv[3] = wv[2]; + wv[2] = wv[1]; + wv[1] = wv[0]; + wv[0] = t1 + t2; + } + + for (j = 0; j < 8; j++) { + ctx->h[j] += wv[j]; + } +#else + PACK32(&sub_block[0], &w[0]); + PACK32(&sub_block[4], &w[1]); + PACK32(&sub_block[8], &w[2]); + PACK32(&sub_block[12], &w[3]); + PACK32(&sub_block[16], &w[4]); + PACK32(&sub_block[20], &w[5]); + PACK32(&sub_block[24], &w[6]); + PACK32(&sub_block[28], &w[7]); + PACK32(&sub_block[32], &w[8]); + PACK32(&sub_block[36], &w[9]); + PACK32(&sub_block[40], &w[10]); + PACK32(&sub_block[44], &w[11]); + PACK32(&sub_block[48], &w[12]); + PACK32(&sub_block[52], &w[13]); + PACK32(&sub_block[56], &w[14]); + PACK32(&sub_block[60], &w[15]); + + SHA256_SCR(16); + SHA256_SCR(17); + SHA256_SCR(18); + SHA256_SCR(19); + SHA256_SCR(20); + SHA256_SCR(21); + SHA256_SCR(22); + SHA256_SCR(23); + SHA256_SCR(24); + SHA256_SCR(25); + SHA256_SCR(26); + SHA256_SCR(27); + SHA256_SCR(28); + SHA256_SCR(29); + SHA256_SCR(30); + SHA256_SCR(31); + SHA256_SCR(32); + SHA256_SCR(33); + SHA256_SCR(34); + SHA256_SCR(35); + SHA256_SCR(36); + SHA256_SCR(37); + SHA256_SCR(38); + SHA256_SCR(39); + SHA256_SCR(40); + SHA256_SCR(41); + SHA256_SCR(42); + SHA256_SCR(43); + SHA256_SCR(44); + SHA256_SCR(45); + SHA256_SCR(46); + SHA256_SCR(47); + SHA256_SCR(48); + SHA256_SCR(49); + SHA256_SCR(50); + SHA256_SCR(51); + SHA256_SCR(52); + SHA256_SCR(53); + SHA256_SCR(54); + SHA256_SCR(55); + SHA256_SCR(56); + SHA256_SCR(57); + SHA256_SCR(58); + SHA256_SCR(59); + SHA256_SCR(60); + SHA256_SCR(61); + SHA256_SCR(62); + SHA256_SCR(63); + + wv[0] = ctx->h[0]; + wv[1] = ctx->h[1]; + wv[2] = ctx->h[2]; + wv[3] = ctx->h[3]; + wv[4] = ctx->h[4]; + wv[5] = ctx->h[5]; + wv[6] = ctx->h[6]; + wv[7] = ctx->h[7]; + + SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 0); + SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 1); + SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 2); + SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 3); + SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 4); + SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 5); + SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 6); + SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 7); + SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 8); + SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 9); + SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 10); + SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 11); + SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 12); + SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 13); + SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 14); + SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 15); + SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 16); + SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 17); + SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 18); + SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 19); + SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 20); + SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 21); + SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 22); + SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 23); + SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 24); + SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 25); + SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 26); + SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 27); + SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 28); + SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 29); + SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 30); + SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 31); + SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 32); + SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 33); + SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 34); + SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 35); + SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 36); + SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 37); + SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 38); + SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 39); + SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 40); + SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 41); + SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 42); + SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 43); + SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 44); + SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 45); + SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 46); + SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 47); + SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 48); + SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 49); + SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 50); + SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 51); + SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 52); + SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 53); + SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 54); + SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 55); + SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 56); + SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 57); + SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 58); + SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 59); + SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 60); + SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 61); + SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 62); + SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 63); + + ctx->h[0] += wv[0]; + ctx->h[1] += wv[1]; + ctx->h[2] += wv[2]; + ctx->h[3] += wv[3]; + ctx->h[4] += wv[4]; + ctx->h[5] += wv[5]; + ctx->h[6] += wv[6]; + ctx->h[7] += wv[7]; +#endif /* !UNROLL_LOOPS */ + } +} + +void avb_sha256_update(AvbSHA256Ctx* ctx, const uint8_t* data, uint32_t len) { + unsigned int block_nb; + unsigned int new_len, rem_len, tmp_len; + const uint8_t* shifted_data; + + tmp_len = AVB_SHA256_BLOCK_SIZE - ctx->len; + rem_len = len < tmp_len ? len : tmp_len; + + avb_memcpy(&ctx->block[ctx->len], data, rem_len); + + if (ctx->len + len < AVB_SHA256_BLOCK_SIZE) { + ctx->len += len; + return; + } + + new_len = len - rem_len; + block_nb = new_len / AVB_SHA256_BLOCK_SIZE; + + shifted_data = data + rem_len; + + SHA256_transform(ctx, ctx->block, 1); + SHA256_transform(ctx, shifted_data, block_nb); + + rem_len = new_len % AVB_SHA256_BLOCK_SIZE; + + avb_memcpy(ctx->block, &shifted_data[block_nb << 6], rem_len); + + ctx->len = rem_len; + ctx->tot_len += (block_nb + 1) << 6; +} + +uint8_t* avb_sha256_final(AvbSHA256Ctx* ctx) { + unsigned int block_nb; + unsigned int pm_len; + unsigned int len_b; +#ifndef UNROLL_LOOPS + int i; +#endif + + block_nb = + (1 + ((AVB_SHA256_BLOCK_SIZE - 9) < (ctx->len % AVB_SHA256_BLOCK_SIZE))); + + len_b = (ctx->tot_len + ctx->len) << 3; + pm_len = block_nb << 6; + + avb_memset(ctx->block + ctx->len, 0, pm_len - ctx->len); + ctx->block[ctx->len] = 0x80; + UNPACK32(len_b, ctx->block + pm_len - 4); + + SHA256_transform(ctx, ctx->block, block_nb); + +#ifndef UNROLL_LOOPS + for (i = 0; i < 8; i++) { + UNPACK32(ctx->h[i], &ctx->buf[i << 2]); + } +#else + UNPACK32(ctx->h[0], &ctx->buf[0]); + UNPACK32(ctx->h[1], &ctx->buf[4]); + UNPACK32(ctx->h[2], &ctx->buf[8]); + UNPACK32(ctx->h[3], &ctx->buf[12]); + UNPACK32(ctx->h[4], &ctx->buf[16]); + UNPACK32(ctx->h[5], &ctx->buf[20]); + UNPACK32(ctx->h[6], &ctx->buf[24]); + UNPACK32(ctx->h[7], &ctx->buf[28]); +#endif /* !UNROLL_LOOPS */ + + return ctx->buf; +} diff --git a/lib/avb/libavb/avb_sha512.c b/lib/avb/libavb/avb_sha512.c new file mode 100644 index 0000000..f2f0ec4 --- /dev/null +++ b/lib/avb/libavb/avb_sha512.c @@ -0,0 +1,380 @@ +/* SHA-256 and SHA-512 implementation based on code by Oliver Gay + * <olivier.gay@a3.epfl.ch> under a BSD-style license. See below. + */ + +/* + * FIPS 180-2 SHA-224/256/384/512 implementation + * Last update: 02/02/2007 + * Issue date: 04/30/2005 + * + * Copyright (C) 2005, 2007 Olivier Gay <olivier.gay@a3.epfl.ch> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the project nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include "avb_sha.h" + +#define SHFR(x, n) (x >> n) +#define ROTR(x, n) ((x >> n) | (x << ((sizeof(x) << 3) - n))) +#define ROTL(x, n) ((x << n) | (x >> ((sizeof(x) << 3) - n))) +#define CH(x, y, z) ((x & y) ^ (~x & z)) +#define MAJ(x, y, z) ((x & y) ^ (x & z) ^ (y & z)) + +#define SHA512_F1(x) (ROTR(x, 28) ^ ROTR(x, 34) ^ ROTR(x, 39)) +#define SHA512_F2(x) (ROTR(x, 14) ^ ROTR(x, 18) ^ ROTR(x, 41)) +#define SHA512_F3(x) (ROTR(x, 1) ^ ROTR(x, 8) ^ SHFR(x, 7)) +#define SHA512_F4(x) (ROTR(x, 19) ^ ROTR(x, 61) ^ SHFR(x, 6)) + +#define UNPACK32(x, str) \ + { \ + *((str) + 3) = (uint8_t)((x)); \ + *((str) + 2) = (uint8_t)((x) >> 8); \ + *((str) + 1) = (uint8_t)((x) >> 16); \ + *((str) + 0) = (uint8_t)((x) >> 24); \ + } + +#define UNPACK64(x, str) \ + { \ + *((str) + 7) = (uint8_t)x; \ + *((str) + 6) = (uint8_t)((uint64_t)x >> 8); \ + *((str) + 5) = (uint8_t)((uint64_t)x >> 16); \ + *((str) + 4) = (uint8_t)((uint64_t)x >> 24); \ + *((str) + 3) = (uint8_t)((uint64_t)x >> 32); \ + *((str) + 2) = (uint8_t)((uint64_t)x >> 40); \ + *((str) + 1) = (uint8_t)((uint64_t)x >> 48); \ + *((str) + 0) = (uint8_t)((uint64_t)x >> 56); \ + } + +#define PACK64(str, x) \ + { \ + *(x) = \ + ((uint64_t) * ((str) + 7)) | ((uint64_t) * ((str) + 6) << 8) | \ + ((uint64_t) * ((str) + 5) << 16) | ((uint64_t) * ((str) + 4) << 24) | \ + ((uint64_t) * ((str) + 3) << 32) | ((uint64_t) * ((str) + 2) << 40) | \ + ((uint64_t) * ((str) + 1) << 48) | ((uint64_t) * ((str) + 0) << 56); \ + } + +/* Macros used for loops unrolling */ + +#define SHA512_SCR(i) \ + { w[i] = SHA512_F4(w[i - 2]) + w[i - 7] + SHA512_F3(w[i - 15]) + w[i - 16]; } + +#define SHA512_EXP(a, b, c, d, e, f, g, h, j) \ + { \ + t1 = wv[h] + SHA512_F2(wv[e]) + CH(wv[e], wv[f], wv[g]) + sha512_k[j] + \ + w[j]; \ + t2 = SHA512_F1(wv[a]) + MAJ(wv[a], wv[b], wv[c]); \ + wv[d] += t1; \ + wv[h] = t1 + t2; \ + } + +static const uint64_t sha512_h0[8] = { + 0x6a09e667f3bcc908ULL, 0xbb67ae8584caa73bULL, 0x3c6ef372fe94f82bULL, + 0xa54ff53a5f1d36f1ULL, 0x510e527fade682d1ULL, 0x9b05688c2b3e6c1fULL, + 0x1f83d9abfb41bd6bULL, 0x5be0cd19137e2179ULL}; + +static const uint64_t sha512_k[80] = { + 0x428a2f98d728ae22ULL, 0x7137449123ef65cdULL, 0xb5c0fbcfec4d3b2fULL, + 0xe9b5dba58189dbbcULL, 0x3956c25bf348b538ULL, 0x59f111f1b605d019ULL, + 0x923f82a4af194f9bULL, 0xab1c5ed5da6d8118ULL, 0xd807aa98a3030242ULL, + 0x12835b0145706fbeULL, 0x243185be4ee4b28cULL, 0x550c7dc3d5ffb4e2ULL, + 0x72be5d74f27b896fULL, 0x80deb1fe3b1696b1ULL, 0x9bdc06a725c71235ULL, + 0xc19bf174cf692694ULL, 0xe49b69c19ef14ad2ULL, 0xefbe4786384f25e3ULL, + 0x0fc19dc68b8cd5b5ULL, 0x240ca1cc77ac9c65ULL, 0x2de92c6f592b0275ULL, + 0x4a7484aa6ea6e483ULL, 0x5cb0a9dcbd41fbd4ULL, 0x76f988da831153b5ULL, + 0x983e5152ee66dfabULL, 0xa831c66d2db43210ULL, 0xb00327c898fb213fULL, + 0xbf597fc7beef0ee4ULL, 0xc6e00bf33da88fc2ULL, 0xd5a79147930aa725ULL, + 0x06ca6351e003826fULL, 0x142929670a0e6e70ULL, 0x27b70a8546d22ffcULL, + 0x2e1b21385c26c926ULL, 0x4d2c6dfc5ac42aedULL, 0x53380d139d95b3dfULL, + 0x650a73548baf63deULL, 0x766a0abb3c77b2a8ULL, 0x81c2c92e47edaee6ULL, + 0x92722c851482353bULL, 0xa2bfe8a14cf10364ULL, 0xa81a664bbc423001ULL, + 0xc24b8b70d0f89791ULL, 0xc76c51a30654be30ULL, 0xd192e819d6ef5218ULL, + 0xd69906245565a910ULL, 0xf40e35855771202aULL, 0x106aa07032bbd1b8ULL, + 0x19a4c116b8d2d0c8ULL, 0x1e376c085141ab53ULL, 0x2748774cdf8eeb99ULL, + 0x34b0bcb5e19b48a8ULL, 0x391c0cb3c5c95a63ULL, 0x4ed8aa4ae3418acbULL, + 0x5b9cca4f7763e373ULL, 0x682e6ff3d6b2b8a3ULL, 0x748f82ee5defb2fcULL, + 0x78a5636f43172f60ULL, 0x84c87814a1f0ab72ULL, 0x8cc702081a6439ecULL, + 0x90befffa23631e28ULL, 0xa4506cebde82bde9ULL, 0xbef9a3f7b2c67915ULL, + 0xc67178f2e372532bULL, 0xca273eceea26619cULL, 0xd186b8c721c0c207ULL, + 0xeada7dd6cde0eb1eULL, 0xf57d4f7fee6ed178ULL, 0x06f067aa72176fbaULL, + 0x0a637dc5a2c898a6ULL, 0x113f9804bef90daeULL, 0x1b710b35131c471bULL, + 0x28db77f523047d84ULL, 0x32caab7b40c72493ULL, 0x3c9ebe0a15c9bebcULL, + 0x431d67c49c100d4cULL, 0x4cc5d4becb3e42b6ULL, 0x597f299cfc657e2aULL, + 0x5fcb6fab3ad6faecULL, 0x6c44198c4a475817ULL}; + +/* SHA-512 implementation */ + +void avb_sha512_init(AvbSHA512Ctx* ctx) { +#ifdef UNROLL_LOOPS_SHA512 + ctx->h[0] = sha512_h0[0]; + ctx->h[1] = sha512_h0[1]; + ctx->h[2] = sha512_h0[2]; + ctx->h[3] = sha512_h0[3]; + ctx->h[4] = sha512_h0[4]; + ctx->h[5] = sha512_h0[5]; + ctx->h[6] = sha512_h0[6]; + ctx->h[7] = sha512_h0[7]; +#else + int i; + + for (i = 0; i < 8; i++) ctx->h[i] = sha512_h0[i]; +#endif /* UNROLL_LOOPS_SHA512 */ + + ctx->len = 0; + ctx->tot_len = 0; +} + +static void SHA512_transform(AvbSHA512Ctx* ctx, const uint8_t* message, + unsigned int block_nb) { + uint64_t w[80]; + uint64_t wv[8]; + uint64_t t1, t2; + const uint8_t* sub_block; + int i, j; + + for (i = 0; i < (int)block_nb; i++) { + sub_block = message + (i << 7); + +#ifdef UNROLL_LOOPS_SHA512 + PACK64(&sub_block[0], &w[0]); + PACK64(&sub_block[8], &w[1]); + PACK64(&sub_block[16], &w[2]); + PACK64(&sub_block[24], &w[3]); + PACK64(&sub_block[32], &w[4]); + PACK64(&sub_block[40], &w[5]); + PACK64(&sub_block[48], &w[6]); + PACK64(&sub_block[56], &w[7]); + PACK64(&sub_block[64], &w[8]); + PACK64(&sub_block[72], &w[9]); + PACK64(&sub_block[80], &w[10]); + PACK64(&sub_block[88], &w[11]); + PACK64(&sub_block[96], &w[12]); + PACK64(&sub_block[104], &w[13]); + PACK64(&sub_block[112], &w[14]); + PACK64(&sub_block[120], &w[15]); + + SHA512_SCR(16); + SHA512_SCR(17); + SHA512_SCR(18); + SHA512_SCR(19); + SHA512_SCR(20); + SHA512_SCR(21); + SHA512_SCR(22); + SHA512_SCR(23); + SHA512_SCR(24); + SHA512_SCR(25); + SHA512_SCR(26); + SHA512_SCR(27); + SHA512_SCR(28); + SHA512_SCR(29); + SHA512_SCR(30); + SHA512_SCR(31); + SHA512_SCR(32); + SHA512_SCR(33); + SHA512_SCR(34); + SHA512_SCR(35); + SHA512_SCR(36); + SHA512_SCR(37); + SHA512_SCR(38); + SHA512_SCR(39); + SHA512_SCR(40); + SHA512_SCR(41); + SHA512_SCR(42); + SHA512_SCR(43); + SHA512_SCR(44); + SHA512_SCR(45); + SHA512_SCR(46); + SHA512_SCR(47); + SHA512_SCR(48); + SHA512_SCR(49); + SHA512_SCR(50); + SHA512_SCR(51); + SHA512_SCR(52); + SHA512_SCR(53); + SHA512_SCR(54); + SHA512_SCR(55); + SHA512_SCR(56); + SHA512_SCR(57); + SHA512_SCR(58); + SHA512_SCR(59); + SHA512_SCR(60); + SHA512_SCR(61); + SHA512_SCR(62); + SHA512_SCR(63); + SHA512_SCR(64); + SHA512_SCR(65); + SHA512_SCR(66); + SHA512_SCR(67); + SHA512_SCR(68); + SHA512_SCR(69); + SHA512_SCR(70); + SHA512_SCR(71); + SHA512_SCR(72); + SHA512_SCR(73); + SHA512_SCR(74); + SHA512_SCR(75); + SHA512_SCR(76); + SHA512_SCR(77); + SHA512_SCR(78); + SHA512_SCR(79); + + wv[0] = ctx->h[0]; + wv[1] = ctx->h[1]; + wv[2] = ctx->h[2]; + wv[3] = ctx->h[3]; + wv[4] = ctx->h[4]; + wv[5] = ctx->h[5]; + wv[6] = ctx->h[6]; + wv[7] = ctx->h[7]; + + j = 0; + + do { + SHA512_EXP(0, 1, 2, 3, 4, 5, 6, 7, j); + j++; + SHA512_EXP(7, 0, 1, 2, 3, 4, 5, 6, j); + j++; + SHA512_EXP(6, 7, 0, 1, 2, 3, 4, 5, j); + j++; + SHA512_EXP(5, 6, 7, 0, 1, 2, 3, 4, j); + j++; + SHA512_EXP(4, 5, 6, 7, 0, 1, 2, 3, j); + j++; + SHA512_EXP(3, 4, 5, 6, 7, 0, 1, 2, j); + j++; + SHA512_EXP(2, 3, 4, 5, 6, 7, 0, 1, j); + j++; + SHA512_EXP(1, 2, 3, 4, 5, 6, 7, 0, j); + j++; + } while (j < 80); + + ctx->h[0] += wv[0]; + ctx->h[1] += wv[1]; + ctx->h[2] += wv[2]; + ctx->h[3] += wv[3]; + ctx->h[4] += wv[4]; + ctx->h[5] += wv[5]; + ctx->h[6] += wv[6]; + ctx->h[7] += wv[7]; +#else + for (j = 0; j < 16; j++) { + PACK64(&sub_block[j << 3], &w[j]); + } + + for (j = 16; j < 80; j++) { + SHA512_SCR(j); + } + + for (j = 0; j < 8; j++) { + wv[j] = ctx->h[j]; + } + + for (j = 0; j < 80; j++) { + t1 = wv[7] + SHA512_F2(wv[4]) + CH(wv[4], wv[5], wv[6]) + sha512_k[j] + + w[j]; + t2 = SHA512_F1(wv[0]) + MAJ(wv[0], wv[1], wv[2]); + wv[7] = wv[6]; + wv[6] = wv[5]; + wv[5] = wv[4]; + wv[4] = wv[3] + t1; + wv[3] = wv[2]; + wv[2] = wv[1]; + wv[1] = wv[0]; + wv[0] = t1 + t2; + } + + for (j = 0; j < 8; j++) ctx->h[j] += wv[j]; +#endif /* UNROLL_LOOPS_SHA512 */ + } +} + +void avb_sha512_update(AvbSHA512Ctx* ctx, const uint8_t* data, uint32_t len) { + unsigned int block_nb; + unsigned int new_len, rem_len, tmp_len; + const uint8_t* shifted_data; + + tmp_len = AVB_SHA512_BLOCK_SIZE - ctx->len; + rem_len = len < tmp_len ? len : tmp_len; + + avb_memcpy(&ctx->block[ctx->len], data, rem_len); + + if (ctx->len + len < AVB_SHA512_BLOCK_SIZE) { + ctx->len += len; + return; + } + + new_len = len - rem_len; + block_nb = new_len / AVB_SHA512_BLOCK_SIZE; + + shifted_data = data + rem_len; + + SHA512_transform(ctx, ctx->block, 1); + SHA512_transform(ctx, shifted_data, block_nb); + + rem_len = new_len % AVB_SHA512_BLOCK_SIZE; + + avb_memcpy(ctx->block, &shifted_data[block_nb << 7], rem_len); + + ctx->len = rem_len; + ctx->tot_len += (block_nb + 1) << 7; +} + +uint8_t* avb_sha512_final(AvbSHA512Ctx* ctx) { + unsigned int block_nb; + unsigned int pm_len; + unsigned int len_b; + +#ifndef UNROLL_LOOPS_SHA512 + int i; +#endif + + block_nb = + 1 + ((AVB_SHA512_BLOCK_SIZE - 17) < (ctx->len % AVB_SHA512_BLOCK_SIZE)); + + len_b = (ctx->tot_len + ctx->len) << 3; + pm_len = block_nb << 7; + + avb_memset(ctx->block + ctx->len, 0, pm_len - ctx->len); + ctx->block[ctx->len] = 0x80; + UNPACK32(len_b, ctx->block + pm_len - 4); + + SHA512_transform(ctx, ctx->block, block_nb); + +#ifdef UNROLL_LOOPS_SHA512 + UNPACK64(ctx->h[0], &ctx->buf[0]); + UNPACK64(ctx->h[1], &ctx->buf[8]); + UNPACK64(ctx->h[2], &ctx->buf[16]); + UNPACK64(ctx->h[3], &ctx->buf[24]); + UNPACK64(ctx->h[4], &ctx->buf[32]); + UNPACK64(ctx->h[5], &ctx->buf[40]); + UNPACK64(ctx->h[6], &ctx->buf[48]); + UNPACK64(ctx->h[7], &ctx->buf[56]); +#else + for (i = 0; i < 8; i++) UNPACK64(ctx->h[i], &ctx->buf[i << 3]); +#endif /* UNROLL_LOOPS_SHA512 */ + + return ctx->buf; +} diff --git a/lib/avb/libavb/avb_slot_verify.c b/lib/avb/libavb/avb_slot_verify.c new file mode 100644 index 0000000..57477d2 --- /dev/null +++ b/lib/avb/libavb/avb_slot_verify.c @@ -0,0 +1,857 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_slot_verify.h" +#include "avb_chain_partition_descriptor.h" +#include "avb_footer.h" +#include "avb_hash_descriptor.h" +#include "avb_kernel_cmdline_descriptor.h" +#include "avb_sha.h" +#include "avb_util.h" +#include "avb_vbmeta_image.h" + +/* Maximum allow length (in bytes) of a partition name, including + * ab_suffix. + */ +#define PART_NAME_MAX_SIZE 32 + +/* Maximum number of partitions that can be loaded with avb_slot_verify(). */ +#define MAX_NUMBER_OF_LOADED_PARTITIONS 32 + +/* Maximum size of a vbmeta image - 64 KiB. */ +#define VBMETA_MAX_SIZE (64 * 1024) + +static AvbSlotVerifyResult load_and_verify_hash_partition( + AvbOps* ops, const char* const* requested_partitions, const char* ab_suffix, + const AvbDescriptor* descriptor, AvbSlotVerifyData* slot_data) { + AvbHashDescriptor hash_desc; + const uint8_t* desc_partition_name; + const uint8_t* desc_salt; + const uint8_t* desc_digest; + char part_name[PART_NAME_MAX_SIZE]; + AvbSlotVerifyResult ret; + AvbIOResult io_ret; + uint8_t* image_buf = NULL; + size_t part_num_read; + uint8_t* digest; + size_t digest_len; + const char* found; + + if (!avb_hash_descriptor_validate_and_byteswap( + (const AvbHashDescriptor*)descriptor, &hash_desc)) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + desc_partition_name = + ((const uint8_t*)descriptor) + sizeof(AvbHashDescriptor); + desc_salt = desc_partition_name + hash_desc.partition_name_len; + desc_digest = desc_salt + hash_desc.salt_len; + + if (!avb_validate_utf8(desc_partition_name, hash_desc.partition_name_len)) { + avb_error("Partition name is not valid UTF-8.\n"); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + if (!avb_str_concat( + part_name, sizeof part_name, (const char*)desc_partition_name, + hash_desc.partition_name_len, ab_suffix, avb_strlen(ab_suffix))) { + avb_error("Partition name and suffix does not fit.\n"); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + image_buf = avb_malloc(hash_desc.image_size); + if (image_buf == NULL) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto out; + } + + io_ret = + ops->read_from_partition(ops, part_name, 0 /* offset */, + hash_desc.image_size, image_buf, &part_num_read); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto out; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_errorv(part_name, ": Error loading data from partition.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; + goto out; + } + if (part_num_read != hash_desc.image_size) { + avb_errorv(part_name, ": Read fewer than requested bytes.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; + goto out; + } + + if (avb_strcmp((const char*)hash_desc.hash_algorithm, "sha256") == 0) { + AvbSHA256Ctx sha256_ctx; + avb_sha256_init(&sha256_ctx); + avb_sha256_update(&sha256_ctx, desc_salt, hash_desc.salt_len); + avb_sha256_update(&sha256_ctx, image_buf, hash_desc.image_size); + digest = avb_sha256_final(&sha256_ctx); + digest_len = AVB_SHA256_DIGEST_SIZE; + } else if (avb_strcmp((const char*)hash_desc.hash_algorithm, "sha512") == 0) { + AvbSHA512Ctx sha512_ctx; + avb_sha512_init(&sha512_ctx); + avb_sha512_update(&sha512_ctx, desc_salt, hash_desc.salt_len); + avb_sha512_update(&sha512_ctx, image_buf, hash_desc.image_size); + digest = avb_sha512_final(&sha512_ctx); + digest_len = AVB_SHA512_DIGEST_SIZE; + } else { + avb_errorv(part_name, ": Unsupported hash algorithm.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + if (digest_len != hash_desc.digest_len) { + avb_errorv(part_name, ": Digest in descriptor not of expected size.\n", + NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + if (avb_safe_memcmp(digest, desc_digest, digest_len) != 0) { + avb_errorv(part_name, + ": Hash of data does not match digest in descriptor.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION; + goto out; + } + + ret = AVB_SLOT_VERIFY_RESULT_OK; + + /* If this is the requested partition, copy to slot_data. */ + found = + avb_strv_find_str(requested_partitions, (const char*)desc_partition_name, + hash_desc.partition_name_len); + if (found != NULL) { + AvbPartitionData* loaded_partition; + if (slot_data->num_loaded_partitions == MAX_NUMBER_OF_LOADED_PARTITIONS) { + avb_errorv(part_name, ": Too many loaded partitions.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto out; + } + loaded_partition = + &slot_data->loaded_partitions[slot_data->num_loaded_partitions++]; + loaded_partition->partition_name = avb_strdup(found); + loaded_partition->data_size = hash_desc.image_size; + loaded_partition->data = image_buf; + image_buf = NULL; + } + +out: + if (image_buf != NULL) { + avb_free(image_buf); + } + return ret; +} + +static AvbSlotVerifyResult load_and_verify_vbmeta( + AvbOps* ops, const char* const* requested_partitions, const char* ab_suffix, + int rollback_index_slot, const char* partition_name, + size_t partition_name_len, const uint8_t* expected_public_key, + size_t expected_public_key_length, AvbSlotVerifyData* slot_data, + AvbAlgorithmType* out_algorithm_type) { + char full_partition_name[PART_NAME_MAX_SIZE]; + AvbSlotVerifyResult ret; + AvbIOResult io_ret; + size_t vbmeta_offset; + size_t vbmeta_size; + uint8_t* vbmeta_buf = NULL; + size_t vbmeta_num_read; + AvbVBMetaVerifyResult vbmeta_ret; + const uint8_t* pk_data; + size_t pk_len; + AvbVBMetaImageHeader vbmeta_header; + uint64_t stored_rollback_index; + const AvbDescriptor** descriptors = NULL; + size_t num_descriptors; + size_t n; + int is_main_vbmeta; + + avb_assert(slot_data != NULL); + + is_main_vbmeta = (avb_strcmp(partition_name, "vbmeta") == 0); + + if (!avb_validate_utf8((const uint8_t*)partition_name, partition_name_len)) { + avb_error("Partition name is not valid UTF-8.\n"); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + /* Construct full partition name. */ + if (!avb_str_concat(full_partition_name, sizeof full_partition_name, + partition_name, partition_name_len, ab_suffix, + avb_strlen(ab_suffix))) { + avb_error("Partition name and suffix does not fit.\n"); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + avb_debugv("Loading vbmeta struct from partition '", full_partition_name, + "'.\n", NULL); + + /* If we're loading from the main vbmeta partition, the vbmeta + * struct is in the beginning. Otherwise we have to locate it via a + * footer. + */ + if (is_main_vbmeta) { + vbmeta_offset = 0; + vbmeta_size = VBMETA_MAX_SIZE; + } else { + uint8_t footer_buf[AVB_FOOTER_SIZE]; + size_t footer_num_read; + AvbFooter footer; + + io_ret = + ops->read_from_partition(ops, full_partition_name, -AVB_FOOTER_SIZE, + AVB_FOOTER_SIZE, footer_buf, &footer_num_read); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto out; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_errorv(full_partition_name, ": Error loading footer.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; + goto out; + } + avb_assert(footer_num_read == AVB_FOOTER_SIZE); + + if (!avb_footer_validate_and_byteswap((const AvbFooter*)footer_buf, + &footer)) { + avb_errorv(full_partition_name, ": Error validating footer.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + /* Basic footer sanity check since the data is untrusted. */ + if (footer.vbmeta_size > VBMETA_MAX_SIZE) { + avb_errorv(full_partition_name, ": Invalid vbmeta size in footer.\n", + NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + vbmeta_offset = footer.vbmeta_offset; + vbmeta_size = footer.vbmeta_size; + } + + vbmeta_buf = avb_malloc(vbmeta_size); + if (vbmeta_buf == NULL) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto out; + } + + io_ret = ops->read_from_partition(ops, full_partition_name, vbmeta_offset, + vbmeta_size, vbmeta_buf, &vbmeta_num_read); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto out; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_errorv(full_partition_name, ": Error loading vbmeta data.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; + goto out; + } + avb_assert(vbmeta_num_read <= vbmeta_size); + + /* Check if the image is properly signed and get the public key used + * to sign the image. + */ + vbmeta_ret = + avb_vbmeta_image_verify(vbmeta_buf, vbmeta_num_read, &pk_data, &pk_len); + if (vbmeta_ret != AVB_VBMETA_VERIFY_RESULT_OK) { + avb_errorv(full_partition_name, ": Error verifying vbmeta image.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION; + goto out; + } + + /* Check if key used to make signature matches what is expected. */ + if (expected_public_key != NULL) { + avb_assert(!is_main_vbmeta); + if (expected_public_key_length != pk_len || + avb_safe_memcmp(expected_public_key, pk_data, pk_len) != 0) { + avb_errorv(full_partition_name, + ": Public key used to sign data does not match key in chain " + "partition descriptor.\n", + NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED; + goto out; + } + } else { + bool key_is_trusted = false; + + avb_assert(is_main_vbmeta); + io_ret = + ops->validate_vbmeta_public_key(ops, pk_data, pk_len, &key_is_trusted); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto out; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_errorv(full_partition_name, + ": Error while checking public key used to sign data.\n", + NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; + goto out; + } + if (!key_is_trusted) { + avb_errorv(full_partition_name, + ": Public key used to sign data rejected.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED; + goto out; + } + } + + avb_vbmeta_image_header_to_host_byte_order((AvbVBMetaImageHeader*)vbmeta_buf, + &vbmeta_header); + + /* Check rollback index. */ + io_ret = ops->read_rollback_index(ops, rollback_index_slot, + &stored_rollback_index); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto out; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_errorv(full_partition_name, + ": Error getting rollback index for slot.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; + goto out; + } + if (vbmeta_header.rollback_index < stored_rollback_index) { + avb_errorv( + full_partition_name, + ": Image rollback index is less than the stored rollback index.\n", + NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX; + goto out; + } + + /* Now go through all descriptors and take the appropriate action: + * + * - hash descriptor: Load data from partition, calculate hash, and + * checks that it matches what's in the hash descriptor. + * + * - hashtree descriptor: Do nothing since verification happens + * on-the-fly from within the OS. + * + * - chained partition descriptor: Load the footer, load the vbmeta + * image, verify vbmeta image (includes rollback checks, hash + * checks, bail on chained partitions). + */ + descriptors = + avb_descriptor_get_all(vbmeta_buf, vbmeta_num_read, &num_descriptors); + for (n = 0; n < num_descriptors; n++) { + AvbDescriptor desc; + + if (!avb_descriptor_validate_and_byteswap(descriptors[n], &desc)) { + avb_errorv(full_partition_name, ": Descriptor is invalid.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + switch (desc.tag) { + case AVB_DESCRIPTOR_TAG_HASH: { + AvbSlotVerifyResult sub_ret; + sub_ret = load_and_verify_hash_partition( + ops, requested_partitions, ab_suffix, descriptors[n], slot_data); + if (sub_ret != AVB_SLOT_VERIFY_RESULT_OK) { + ret = sub_ret; + goto out; + } + } break; + + case AVB_DESCRIPTOR_TAG_CHAIN_PARTITION: { + AvbSlotVerifyResult sub_ret; + AvbChainPartitionDescriptor chain_desc; + const uint8_t* chain_partition_name; + const uint8_t* chain_public_key; + + /* Only allow CHAIN_PARTITION descriptors in the main vbmeta image. */ + if (!is_main_vbmeta) { + avb_errorv(full_partition_name, + ": Encountered chain descriptor not in main image.\n", + NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + if (!avb_chain_partition_descriptor_validate_and_byteswap( + (AvbChainPartitionDescriptor*)descriptors[n], &chain_desc)) { + avb_errorv(full_partition_name, + ": Chain partition descriptor is invalid.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + chain_partition_name = ((const uint8_t*)descriptors[n]) + + sizeof(AvbChainPartitionDescriptor); + chain_public_key = chain_partition_name + chain_desc.partition_name_len; + + sub_ret = load_and_verify_vbmeta( + ops, requested_partitions, ab_suffix, + chain_desc.rollback_index_slot, (const char*)chain_partition_name, + chain_desc.partition_name_len, chain_public_key, + chain_desc.public_key_len, slot_data, + NULL /* out_algorithm_type */); + if (sub_ret != AVB_SLOT_VERIFY_RESULT_OK) { + ret = sub_ret; + goto out; + } + } break; + + case AVB_DESCRIPTOR_TAG_KERNEL_CMDLINE: { + const uint8_t* kernel_cmdline; + AvbKernelCmdlineDescriptor kernel_cmdline_desc; + + if (!avb_kernel_cmdline_descriptor_validate_and_byteswap( + (AvbKernelCmdlineDescriptor*)descriptors[n], + &kernel_cmdline_desc)) { + avb_errorv(full_partition_name, + ": Kernel cmdline descriptor is invalid.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + kernel_cmdline = ((const uint8_t*)descriptors[n]) + + sizeof(AvbKernelCmdlineDescriptor); + + if (!avb_validate_utf8(kernel_cmdline, + kernel_cmdline_desc.kernel_cmdline_length)) { + avb_errorv(full_partition_name, + ": Kernel cmdline is not valid UTF-8.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + if (slot_data->cmdline == NULL) { + slot_data->cmdline = + avb_calloc(kernel_cmdline_desc.kernel_cmdline_length + 1); + if (slot_data->cmdline == NULL) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto out; + } + avb_memcpy(slot_data->cmdline, kernel_cmdline, + kernel_cmdline_desc.kernel_cmdline_length); + } else { + /* new cmdline is: <existing_cmdline> + ' ' + <newcmdline> + '\0' */ + size_t orig_size = avb_strlen(slot_data->cmdline); + size_t new_size = + orig_size + 1 + kernel_cmdline_desc.kernel_cmdline_length + 1; + char* new_cmdline = avb_calloc(new_size); + if (new_cmdline == NULL) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto out; + } + avb_memcpy(new_cmdline, slot_data->cmdline, orig_size); + new_cmdline[orig_size] = ' '; + avb_memcpy(new_cmdline + orig_size + 1, kernel_cmdline, + kernel_cmdline_desc.kernel_cmdline_length); + avb_free(slot_data->cmdline); + slot_data->cmdline = new_cmdline; + } + } break; + + /* Explicit fall-through */ + case AVB_DESCRIPTOR_TAG_PROPERTY: + case AVB_DESCRIPTOR_TAG_HASHTREE: + /* Do nothing. */ + break; + } + } + + ret = AVB_SLOT_VERIFY_RESULT_OK; + + /* So far, so good. Copy needed data to user, if requested. */ + if (is_main_vbmeta) { + if (slot_data->vbmeta_data != NULL) { + avb_free(slot_data->vbmeta_data); + } + /* Note that |vbmeta_buf| is actually |vbmeta_num_read| bytes long + * and this includes data past the end of the image. Pass the + * actual size of the vbmeta image. Also, no need to use + * avb_safe_add() since the header has already been verified. + */ + slot_data->vbmeta_size = sizeof(AvbVBMetaImageHeader) + + vbmeta_header.authentication_data_block_size + + vbmeta_header.auxiliary_data_block_size; + slot_data->vbmeta_data = vbmeta_buf; + vbmeta_buf = NULL; + } + + if (rollback_index_slot >= AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_SLOTS) { + avb_errorv(full_partition_name, ": Invalid rollback_index_slot.\n", NULL); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA; + goto out; + } + + slot_data->rollback_indexes[rollback_index_slot] = + vbmeta_header.rollback_index; + + if (out_algorithm_type != NULL) { + *out_algorithm_type = (AvbAlgorithmType)vbmeta_header.algorithm_type; + } + +out: + if (vbmeta_buf != NULL) { + avb_free(vbmeta_buf); + } + if (descriptors != NULL) { + avb_free(descriptors); + } + return ret; +} + +#define NUM_GUIDS 2 + +/* Substitutes all variables (e.g. $(ANDROID_SYSTEM_PARTUUID)) with + * values. Returns NULL on OOM, otherwise the cmdline with values + * replaced. + */ +static char* sub_cmdline(AvbOps* ops, const char* cmdline, + const char* ab_suffix) { + const char* part_name_str[NUM_GUIDS] = {"system", "boot"}; + const char* replace_str[NUM_GUIDS] = {"$(ANDROID_SYSTEM_PARTUUID)", + "$(ANDROID_BOOT_PARTUUID)"}; + char* ret = NULL; + AvbIOResult io_ret; + + /* Replace unique partition GUIDs */ + for (size_t n = 0; n < NUM_GUIDS; n++) { + char part_name[PART_NAME_MAX_SIZE]; + char guid_buf[37]; + char* new_ret; + + if (!avb_str_concat(part_name, sizeof part_name, part_name_str[n], + avb_strlen(part_name_str[n]), ab_suffix, + avb_strlen(ab_suffix))) { + avb_error("Partition name and suffix does not fit.\n"); + goto fail; + } + + io_ret = ops->get_unique_guid_for_partition(ops, part_name, guid_buf, + sizeof guid_buf); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + return NULL; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_error("Error getting unique GUID for partition.\n"); + goto fail; + } + + if (ret == NULL) { + new_ret = avb_replace(cmdline, replace_str[n], guid_buf); + } else { + new_ret = avb_replace(ret, replace_str[n], guid_buf); + } + if (new_ret == NULL) { + goto fail; + } + ret = new_ret; + } + + return ret; + +fail: + if (ret != NULL) { + avb_free(ret); + } + return NULL; +} + +static int cmdline_append_option(AvbSlotVerifyData* slot_data, const char* key, + const char* value) { + size_t offset, key_len, value_len; + char* new_cmdline; + + key_len = avb_strlen(key); + value_len = avb_strlen(value); + + offset = 0; + if (slot_data->cmdline != NULL) { + offset = avb_strlen(slot_data->cmdline); + if (offset > 0) { + offset += 1; + } + } + + new_cmdline = avb_calloc(offset + key_len + value_len + 2); + if (new_cmdline == NULL) { + return 0; + } + if (offset > 0) { + avb_memcpy(new_cmdline, slot_data->cmdline, offset - 1); + new_cmdline[offset - 1] = ' '; + } + avb_memcpy(new_cmdline + offset, key, key_len); + new_cmdline[offset + key_len] = '='; + avb_memcpy(new_cmdline + offset + key_len + 1, value, value_len); + if (slot_data->cmdline != NULL) { + avb_free(slot_data->cmdline); + } + slot_data->cmdline = new_cmdline; + + return 1; +} + +static int cmdline_append_uint64_base10(AvbSlotVerifyData* slot_data, + const char* key, uint64_t value) { + const int MAX_DIGITS = 32; + char rev_digits[MAX_DIGITS]; + char digits[MAX_DIGITS]; + size_t n, num_digits; + + for (num_digits = 0; num_digits < MAX_DIGITS - 1;) { + rev_digits[num_digits++] = (value % 10) + '0'; + value /= 10; + if (value == 0) { + break; + } + } + + for (n = 0; n < num_digits; n++) { + digits[n] = rev_digits[num_digits - 1 - n]; + } + digits[n] = '\0'; + + return cmdline_append_option(slot_data, key, digits); +} + +static int cmdline_append_hex(AvbSlotVerifyData* slot_data, const char* key, + const uint8_t* data, size_t data_len) { + char hex_digits[17] = "0123456789abcdef"; + char* hex_data; + int ret; + size_t n; + + hex_data = avb_malloc(data_len * 2 + 1); + if (hex_data == NULL) return 0; + + for (n = 0; n < data_len; n++) { + hex_data[n * 2] = hex_digits[data[n] >> 4]; + hex_data[n * 2 + 1] = hex_digits[data[n] & 0x0f]; + } + hex_data[n * 2] = '\0'; + + ret = cmdline_append_option(slot_data, key, hex_data); + avb_free(hex_data); + return ret; +} + +AvbSlotVerifyResult avb_slot_verify(AvbOps* ops, + const char* const* requested_partitions, + const char* ab_suffix, + AvbSlotVerifyData** out_data) { + AvbSlotVerifyResult ret; + AvbSlotVerifyData* slot_data = NULL; + AvbAlgorithmType algorithm_type = AVB_ALGORITHM_TYPE_NONE; + AvbIOResult io_ret; + + if (out_data != NULL) { + *out_data = NULL; + } + + slot_data = avb_calloc(sizeof(AvbSlotVerifyData)); + if (slot_data == NULL) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto fail; + } + slot_data->loaded_partitions = + avb_calloc(sizeof(AvbPartitionData) * MAX_NUMBER_OF_LOADED_PARTITIONS); + if (slot_data->loaded_partitions == NULL) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto fail; + } + + ret = load_and_verify_vbmeta( + ops, requested_partitions, ab_suffix, 0 /* rollback_index_slot */, + "vbmeta", avb_strlen("vbmeta"), NULL /* expected_public_key */, + 0 /* expected_public_key_length */, slot_data, &algorithm_type); + + /* If things check out, mangle the kernel command-line as needed. */ + if (ret == AVB_SLOT_VERIFY_RESULT_OK) { + /* Fill in |ab_suffix| field. */ + slot_data->ab_suffix = avb_strdup(ab_suffix); + if (slot_data->ab_suffix == NULL) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto fail; + } + + /* Substitute $(ANDROID_SYSTEM_PARTUUID) and friends. */ + if (slot_data->cmdline != NULL) { + char* new_cmdline = sub_cmdline(ops, slot_data->cmdline, ab_suffix); + if (new_cmdline == NULL) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto fail; + } + avb_free(slot_data->cmdline); + slot_data->cmdline = new_cmdline; + } + + /* Add androidboot.slot_suffix, if applicable. */ + if (avb_strlen(ab_suffix) > 0) { + if (!cmdline_append_option(slot_data, "androidboot.slot_suffix", + ab_suffix)) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto fail; + } + } + + /* Set androidboot.avb.device_state to "locked" or "unlocked". */ + bool is_device_unlocked; + io_ret = ops->read_is_device_unlocked(ops, &is_device_unlocked); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto fail; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_error("Error getting device state.\n"); + ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO; + goto fail; + } + if (!cmdline_append_option(slot_data, "androidboot.vbmeta.device_state", + is_device_unlocked ? "unlocked" : "locked")) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto fail; + } + + /* Set androidboot.vbmeta.{hash_alg, size, digest} - use same hash + * function as is used to sign vbmeta. + */ + switch (algorithm_type) { + /* Explicit fallthrough. */ + case AVB_ALGORITHM_TYPE_NONE: + case AVB_ALGORITHM_TYPE_SHA256_RSA2048: + case AVB_ALGORITHM_TYPE_SHA256_RSA4096: + case AVB_ALGORITHM_TYPE_SHA256_RSA8192: { + AvbSHA256Ctx ctx; + avb_sha256_init(&ctx); + avb_sha256_update(&ctx, slot_data->vbmeta_data, slot_data->vbmeta_size); + if (!cmdline_append_option(slot_data, "androidboot.vbmeta.hash_alg", + "sha256") || + !cmdline_append_uint64_base10(slot_data, "androidboot.vbmeta.size", + slot_data->vbmeta_size) || + !cmdline_append_hex(slot_data, "androidboot.vbmeta.digest", + avb_sha256_final(&ctx), + AVB_SHA256_DIGEST_SIZE)) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto fail; + } + } break; + /* Explicit fallthrough. */ + case AVB_ALGORITHM_TYPE_SHA512_RSA2048: + case AVB_ALGORITHM_TYPE_SHA512_RSA4096: + case AVB_ALGORITHM_TYPE_SHA512_RSA8192: { + AvbSHA512Ctx ctx; + avb_sha512_init(&ctx); + avb_sha512_update(&ctx, slot_data->vbmeta_data, slot_data->vbmeta_size); + if (!cmdline_append_option(slot_data, "androidboot.vbmeta.hash_alg", + "sha512") || + !cmdline_append_uint64_base10(slot_data, "androidboot.vbmeta.size", + slot_data->vbmeta_size) || + !cmdline_append_hex(slot_data, "androidboot.vbmeta.digest", + avb_sha512_final(&ctx), + AVB_SHA512_DIGEST_SIZE)) { + ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM; + goto fail; + } + } break; + case _AVB_ALGORITHM_NUM_TYPES: + avb_assert_not_reached(); + break; + } + + if (out_data != NULL) { + *out_data = slot_data; + } else { + avb_slot_verify_data_free(slot_data); + } + } + + return ret; + +fail: + if (slot_data != NULL) { + avb_slot_verify_data_free(slot_data); + } + return ret; +} + +void avb_slot_verify_data_free(AvbSlotVerifyData* data) { + if (data->ab_suffix != NULL) { + avb_free(data->ab_suffix); + } + if (data->vbmeta_data != NULL) { + avb_free(data->vbmeta_data); + } + if (data->cmdline != NULL) { + avb_free(data->cmdline); + } + if (data->loaded_partitions != NULL) { + size_t n; + for (n = 0; n < data->num_loaded_partitions; n++) { + AvbPartitionData* loaded_partition = &data->loaded_partitions[n]; + if (loaded_partition->partition_name != NULL) { + avb_free(loaded_partition->partition_name); + } + if (loaded_partition->data != NULL) { + avb_free(loaded_partition->data); + } + } + avb_free(data->loaded_partitions); + } + avb_free(data); +} + +const char* avb_slot_verify_result_to_string(AvbSlotVerifyResult result) { + const char* ret = NULL; + + switch (result) { + case AVB_SLOT_VERIFY_RESULT_OK: + ret = "OK"; + break; + case AVB_SLOT_VERIFY_RESULT_ERROR_OOM: + ret = "ERROR_OOM"; + break; + case AVB_SLOT_VERIFY_RESULT_ERROR_IO: + ret = "ERROR_IO"; + break; + case AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION: + ret = "ERROR_VERIFICATION"; + break; + case AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX: + ret = "ERROR_ROLLBACK_INDEX"; + break; + case AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED: + ret = "ERROR_PUBLIC_KEY_REJECTED"; + break; + case AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA: + ret = "ERROR_INVALID_METADATA"; + break; + /* Do not add a 'default:' case here because of -Wswitch. */ + } + + if (ret == NULL) { + avb_error("Unknown AvbSlotVerifyResult value.\n"); + ret = "(unknown)"; + } + + return ret; +} diff --git a/lib/avb/libavb/avb_slot_verify.h b/lib/avb/libavb/avb_slot_verify.h new file mode 100644 index 0000000..d644a44 --- /dev/null +++ b/lib/avb/libavb/avb_slot_verify.h @@ -0,0 +1,195 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_SLOT_VERIFY_H_ +#define AVB_SLOT_VERIFY_H_ + +#include "avb_ops.h" +#include "avb_vbmeta_image.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* Return codes used in avb_slot_verify(), see that function for + * documentation for each field. + * + * Use avb_slot_verify_result_to_string() to get a textual + * representation usable for error/debug output. + */ +typedef enum { + AVB_SLOT_VERIFY_RESULT_OK, + AVB_SLOT_VERIFY_RESULT_ERROR_OOM, + AVB_SLOT_VERIFY_RESULT_ERROR_IO, + AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION, + AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX, + AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED, + AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA +} AvbSlotVerifyResult; + +/* Get a textual representation of |result|. */ +const char* avb_slot_verify_result_to_string(AvbSlotVerifyResult result); + +/* Maximum number of rollback index locations supported. */ +#define AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_SLOTS 4 + +/* AvbPartitionData contains data loaded from partitions when using + * avb_slot_verify(). The |partition_name| field contains the name of + * the partition, |data| points to the loaded data which is + * |data_size| bytes long. + * + * Note that this is strictly less than the partition size - it's only + * the image stored there, not the entire partition nor any of the + * metadata. + */ +typedef struct { + char* partition_name; + uint8_t* data; + size_t data_size; +} AvbPartitionData; + +/* AvbSlotVerifyData contains data needed to boot a particular slot + * and is returned by avb_slot_verify() if partitions in a slot are + * successfully verified. + * + * All data pointed to by this struct - including data in each item in + * the |partitions| array - will be freed when the + * avb_slot_verify_data_free() function is called. + * + * The |ab_suffix| field is the copy of the of |ab_suffix| field + * passed to avb_slot_verify(). It is the A/B suffix of the slot. + * + * The partitions loaded and verified from from the slot are + * accessible in the |loaded_partitions| array. The field + * |num_loaded_partitions| contains the number of elements in this + * array. The order of partitions in this array may not necessarily be + * the same order as in the passed-in |requested_partitions| array. + * + * The verified vbmeta image in the 'vbmeta' partition of the slot is + * accessible from the |vbmeta_data| field and is of length + * |vbmeta_size| bytes. You can use this data with + * e.g. avb_descriptor_get_all(). + * + * Rollback indexes for the verified slot are stored in the + * |rollback_indexes| field. Note that avb_slot_verify() will NEVER + * modify stored_rollback_index[n] locations e.g. it will never use + * the write_rollback_index() AvbOps operation. Instead it is the job + * of the caller of avb_slot_verify() to do this based on e.g. A/B + * policy and other factors. See libavb_ab/avb_ab_flow.c for an + * example of how to do this. + * + * The |cmdline| field is a NUL-terminated string in UTF-8 resulting + * from concatenating all |AvbKernelCmdlineDescriptor| and then + * performing proper substitution of the variables + * $(ANDROID_SYSTEM_PARTUUID) and $(ANDROID_BOOT_PARTUUID) using the + * get_unique_guid_for_partition() operation in |AvbOps|. + * + * Additionally, the |cmdline| field will have the following kernel + * command-line options set: + * + * androidboot.avb.device_state: set to "locked" or "unlocked" + * depending on the result of the result of AvbOps's + * read_is_unlocked() function. + * + * androidboot.slot_suffix: If |ab_suffix| as passed into + * avb_slot_verify() is non-empty, this variable will be set to its + * value. + * + * androidboot.vbmeta.{hash_alg, size, digest}: Will be set to + * the digest of the vbmeta image. + * + * This struct may grow in the future without it being considered an + * ABI break. + */ +typedef struct { + char* ab_suffix; + uint8_t* vbmeta_data; + size_t vbmeta_size; + AvbPartitionData* loaded_partitions; + size_t num_loaded_partitions; + char* cmdline; + uint64_t rollback_indexes[AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_SLOTS]; +} AvbSlotVerifyData; + +/* Frees a |AvbSlotVerifyData| including all data it points to. */ +void avb_slot_verify_data_free(AvbSlotVerifyData* data); + +/* Performs a full verification of the slot identified by |ab_suffix| + * and load the contents of the partitions whose name is in the + * NULL-terminated string array |requested_partitions| (each partition + * must use hash verification). If not using A/B, pass an empty string + * (e.g. "", not NULL) for |ab_suffix|. + * + * Typically the |requested_partitions| array only contains a single + * item for the boot partition, 'boot'. + * + * Verification includes loading data from the 'vbmeta', all hash + * partitions, and possibly other partitions (with |ab_suffix| + * appended), inspecting rollback indexes, and checking if the public + * key used to sign the data is acceptable. The functions in |ops| + * will be used to do this. + * + * If |out_data| is not NULL, it will be set to a newly allocated + * |AvbSlotVerifyData| struct containing all the data needed to + * actually boot the slot. This data structure should be freed with + * avb_slot_verify_data_free() when you are done with it. + * + * AVB_SLOT_VERIFY_RESULT_OK is returned if everything is verified + * correctly and all public keys are accepted. + * + * AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED is returned if + * everything is verified correctly out but one or more public keys + * are not accepted. This includes the case where integrity data is + * not signed. + * + * AVB_SLOT_VERIFY_RESULT_ERROR_OOM is returned if unable to + * allocate memory. + * + * AVB_SLOT_VERIFY_RESULT_ERROR_IO is returned if an I/O error + * occurred while trying to load data or get a rollback index. + * + * AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION is returned if the data + * did not verify, e.g. the digest didn't match or signature checks + * failed. + * + * AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX is returned if a + * rollback index was less than its stored value. + * + * AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA is returned if some + * of the metadata is invalid or inconsistent. + */ +AvbSlotVerifyResult avb_slot_verify(AvbOps* ops, + const char* const* requested_partitions, + const char* ab_suffix, + AvbSlotVerifyData** out_data); + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_SLOT_VERIFY_H_ */ diff --git a/lib/avb/libavb/avb_sysdeps.h b/lib/avb/libavb/avb_sysdeps.h new file mode 100644 index 0000000..7fe9d06 --- /dev/null +++ b/lib/avb/libavb/avb_sysdeps.h @@ -0,0 +1,113 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_SYSDEPS_H_ +#define AVB_SYSDEPS_H_ + +#ifdef __cplusplus +extern "C" { +#endif + +/* Change these includes to match your platform to bring in the + * equivalent types available in a normal C runtime. At least things + * like uint8_t, uint64_t, and bool (with |false|, |true| keywords) + * must be present. + */ +#include <compiler.h> +#include <inttypes.h> +/* If you don't have gcc or clang, these attribute macros may need to + * be adjusted. + */ +#define AVB_ATTR_WARN_UNUSED_RESULT __attribute__((warn_unused_result)) +#define AVB_ATTR_PACKED __attribute__((packed)) +#define AVB_ATTR_NO_RETURN __attribute__((noreturn)) +#define AVB_ATTR_SENTINEL __attribute__((__sentinel__)); + +/* Size in bytes used for word-alignment. + * + * Change this to match your architecture - must be a power of two. + */ +#define AVB_WORD_ALIGNMENT_SIZE 8 + +/* Compare |n| bytes in |src1| and |src2|. + * + * Returns an integer less than, equal to, or greater than zero if the + * first |n| bytes of |src1| is found, respectively, to be less than, + * to match, or be greater than the first |n| bytes of |src2|. */ +int avb_memcmp(const void* src1, const void* src2, + size_t n) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Compare two strings. + * + * Return an integer less than, equal to, or greater than zero if |s1| + * is found, respectively, to be less than, to match, or be greater + * than |s2|. + */ +int avb_strcmp(const char* s1, const char* s2); + +/* Copy |n| bytes from |src| to |dest|. */ +void* avb_memcpy(void* dest, const void* src, size_t n); + +/* Set |n| bytes starting at |s| to |c|. Returns |dest|. */ +void* avb_memset(void* dest, const int c, size_t n); + +/* Prints out a message. The string passed must be a NUL-terminated + * UTF-8 string. + */ +void avb_print(const char* message); + +/* Prints out a vector of strings. Each argument must point to a + * NUL-terminated UTF-8 string and NULL should be the last argument. + */ +void avb_printv(const char* message, ...) AVB_ATTR_SENTINEL; + +/* Aborts the program or reboots the device. */ +void avb_abort(void) AVB_ATTR_NO_RETURN; + +/* Allocates |size| bytes. Returns NULL if no memory is available, + * otherwise a pointer to the allocated memory. + * + * The memory is not initialized. + * + * The pointer returned is guaranteed to be word-aligned. + * + * The memory should be freed with avb_free() when you are done with it. + */ +void* avb_malloc_(size_t size) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Frees memory previously allocated with avb_malloc(). */ +void avb_free(void* ptr); + +/* Returns the lenght of |str|, excluding the terminating NUL-byte. */ +size_t avb_strlen(const char* str) AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_SYSDEPS_H_ */ diff --git a/lib/avb/libavb/avb_sysdeps_uboot.c b/lib/avb/libavb/avb_sysdeps_uboot.c new file mode 100644 index 0000000..be5c1d2 --- /dev/null +++ b/lib/avb/libavb/avb_sysdeps_uboot.c @@ -0,0 +1,64 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include <common.h> +#include <stdlib.h> +#include <linux/string.h> + +#include "avb_sysdeps.h" + +int avb_memcmp(const void* src1, const void* src2, size_t n) { + return memcmp(src1, src2, n); +} + +void* avb_memcpy(void* dest, const void* src, size_t n) { + return memcpy(dest, src, n); +} + +void* avb_memset(void* dest, const int c, size_t n) { + return memset(dest, c, n); +} + +int avb_strcmp(const char* s1, const char* s2) { return strcmp(s1, s2); } + +size_t avb_strlen(const char* str) { return strlen(str); } + +void avb_abort(void) { panic("avb_abort!\n"); } + +void avb_print(const char* message) { printf("%s", message); } + +void avb_printv(const char* message, ...) { + va_list ap; + const char* m; + + va_start(ap, message); + for (m = message; m != NULL; m = va_arg(ap, const char*)) { + printf("%s", m); + } + va_end(ap); +} + +void* avb_malloc_(size_t size) { return malloc(size); } + +void avb_free(void* ptr) { free(ptr); } diff --git a/lib/avb/libavb/avb_util.c b/lib/avb/libavb/avb_util.c new file mode 100644 index 0000000..435e556 --- /dev/null +++ b/lib/avb/libavb/avb_util.c @@ -0,0 +1,319 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_util.h" + +uint32_t avb_be32toh(uint32_t in) { + uint8_t* d = (uint8_t*)∈ + uint32_t ret; + ret = ((uint32_t)d[0]) << 24; + ret |= ((uint32_t)d[1]) << 16; + ret |= ((uint32_t)d[2]) << 8; + ret |= ((uint32_t)d[3]); + return ret; +} + +uint64_t avb_be64toh(uint64_t in) { + uint8_t* d = (uint8_t*)∈ + uint64_t ret; + ret = ((uint64_t)d[0]) << 56; + ret |= ((uint64_t)d[1]) << 48; + ret |= ((uint64_t)d[2]) << 40; + ret |= ((uint64_t)d[3]) << 32; + ret |= ((uint64_t)d[4]) << 24; + ret |= ((uint64_t)d[5]) << 16; + ret |= ((uint64_t)d[6]) << 8; + ret |= ((uint64_t)d[7]); + return ret; +} + +/* Converts a 32-bit unsigned integer from host to big-endian byte order. */ +uint32_t avb_htobe32(uint32_t in) { + union { + uint32_t word; + uint8_t bytes[4]; + } ret; + ret.bytes[0] = (in >> 24) & 0xff; + ret.bytes[1] = (in >> 16) & 0xff; + ret.bytes[2] = (in >> 8) & 0xff; + ret.bytes[3] = in & 0xff; + return ret.word; +} + +/* Converts a 64-bit unsigned integer from host to big-endian byte order. */ +uint64_t avb_htobe64(uint64_t in) { + union { + uint64_t word; + uint8_t bytes[8]; + } ret; + ret.bytes[0] = (in >> 56) & 0xff; + ret.bytes[1] = (in >> 48) & 0xff; + ret.bytes[2] = (in >> 40) & 0xff; + ret.bytes[3] = (in >> 32) & 0xff; + ret.bytes[4] = (in >> 24) & 0xff; + ret.bytes[5] = (in >> 16) & 0xff; + ret.bytes[6] = (in >> 8) & 0xff; + ret.bytes[7] = in & 0xff; + return ret.word; +} + +int avb_safe_memcmp(const void* s1, const void* s2, size_t n) { + const unsigned char* us1 = s1; + const unsigned char* us2 = s2; + int result = 0; + + if (0 == n) return 0; + + /* + * Code snippet without data-dependent branch due to Nate Lawson + * (nate@root.org) of Root Labs. + */ + while (n--) result |= *us1++ ^ *us2++; + + return result != 0; +} + +bool avb_safe_add_to(uint64_t* value, uint64_t value_to_add) { + uint64_t original_value; + + avb_assert(value != NULL); + + original_value = *value; + + *value += value_to_add; + if (*value < original_value) { + avb_error("Overflow when adding values.\n"); + return false; + } + + return true; +} + +bool avb_safe_add(uint64_t* out_result, uint64_t a, uint64_t b) { + uint64_t dummy; + if (out_result == NULL) out_result = &dummy; + *out_result = a; + return avb_safe_add_to(out_result, b); +} + +bool avb_validate_utf8(const uint8_t* data, size_t num_bytes) { + size_t n; + unsigned int num_cc; + + for (n = 0, num_cc = 0; n < num_bytes; n++) { + uint8_t c = data[n]; + + if (num_cc > 0) { + if ((c & (0x80 | 0x40)) == 0x80) { + /* 10xx xxxx */ + } else { + goto fail; + } + num_cc--; + } else { + if (c < 0x80) { + num_cc = 0; + } else if ((c & (0x80 | 0x40 | 0x20)) == (0x80 | 0x40)) { + /* 110x xxxx */ + num_cc = 1; + } else if ((c & (0x80 | 0x40 | 0x20 | 0x10)) == (0x80 | 0x40 | 0x20)) { + /* 1110 xxxx */ + num_cc = 2; + } else if ((c & (0x80 | 0x40 | 0x20 | 0x10 | 0x08)) == + (0x80 | 0x40 | 0x20 | 0x10)) { + /* 1111 0xxx */ + num_cc = 3; + } else { + goto fail; + } + } + } + + if (num_cc != 0) { + goto fail; + } + + return true; + +fail: + return false; +} + +bool avb_str_concat(char* buf, size_t buf_size, const char* str1, + size_t str1_len, const char* str2, size_t str2_len) { + uint64_t combined_len; + + if (!avb_safe_add(&combined_len, str1_len, str2_len)) { + avb_error("Overflow when adding string sizes.\n"); + return false; + } + + if (combined_len > buf_size - 1) { + avb_error("Insufficient buffer space.\n"); + return false; + } + + avb_memcpy(buf, str1, str1_len); + avb_memcpy(buf + str1_len, str2, str2_len); + buf[combined_len] = '\0'; + + return true; +} + +void* avb_malloc(size_t size) { + void* ret = avb_malloc_(size); + if (ret == NULL) { + avb_error("Failed to allocate memory.\n"); + return NULL; + } + return ret; +} + +void* avb_calloc(size_t size) { + void* ret = avb_malloc(size); + if (ret == NULL) { + return NULL; + } + + avb_memset(ret, '\0', size); + return ret; +} + +char* avb_strdup(const char* str) { + size_t len = avb_strlen(str); + char* ret = avb_malloc(len + 1); + if (ret == NULL) { + return NULL; + } + + avb_memcpy(ret, str, len); + ret[len] = '\0'; + + return ret; +} + +const char* avb_strstr(const char* haystack, const char* needle) { + size_t n, m; + + /* Look through |haystack| and check if the first character of + * |needle| matches. If so, check the rest of |needle|. + */ + for (n = 0; haystack[n] != '\0'; n++) { + if (haystack[n] != needle[0]) continue; + + for (m = 1;; m++) { + if (needle[m] == '\0') { + return haystack + n; + } + + if (haystack[n + m] != needle[m]) break; + } + } + + return NULL; +} + +const char* avb_strv_find_str(const char* const* strings, const char* str, + size_t str_size) { + size_t n; + for (n = 0; strings[n] != NULL; n++) { + if (avb_strlen(strings[n]) == str_size && + avb_memcmp(strings[n], str, str_size) == 0) { + return strings[n]; + } + } + return NULL; +} + +char* avb_replace(const char* str, const char* search, const char* replace) { + char* ret = NULL; + size_t ret_len = 0; + size_t search_len, replace_len; + const char* str_after_last_replace; + + search_len = avb_strlen(search); + replace_len = avb_strlen(replace); + + str_after_last_replace = str; + while (*str != '\0') { + const char* s; + size_t num_before; + size_t num_new; + + s = avb_strstr(str, search); + if (s == NULL) break; + + num_before = s - str; + + if (ret == NULL) { + num_new = num_before + replace_len + 1; + ret = avb_malloc(num_new); + if (ret == NULL) { + goto out; + } + avb_memcpy(ret, str, num_before); + avb_memcpy(ret + num_before, replace, replace_len); + ret[num_new - 1] = '\0'; + ret_len = num_new - 1; + } else { + char* new_str; + num_new = ret_len + num_before + replace_len + 1; + new_str = avb_malloc(num_new); + if (ret == NULL) { + goto out; + } + avb_memcpy(new_str, ret, ret_len); + avb_memcpy(new_str + ret_len, str, num_before); + avb_memcpy(new_str + ret_len + num_before, replace, replace_len); + new_str[num_new - 1] = '\0'; + avb_free(ret); + ret = new_str; + ret_len = num_new - 1; + } + + str = s + search_len; + str_after_last_replace = str; + } + + if (ret == NULL) { + ret = avb_strdup(str_after_last_replace); + if (ret == NULL) { + goto out; + } + } else { + size_t num_remaining = avb_strlen(str_after_last_replace); + size_t num_new = ret_len + num_remaining + 1; + char* new_str = avb_malloc(num_new); + if (ret == NULL) goto out; + avb_memcpy(new_str, ret, ret_len); + avb_memcpy(new_str + ret_len, str_after_last_replace, num_remaining); + new_str[num_new - 1] = '\0'; + avb_free(ret); + ret = new_str; + ret_len = num_new - 1; + } + +out: + return ret; +} diff --git a/lib/avb/libavb/avb_util.h b/lib/avb/libavb/avb_util.h new file mode 100644 index 0000000..d53be97 --- /dev/null +++ b/lib/avb/libavb/avb_util.h @@ -0,0 +1,232 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_UTIL_H_ +#define AVB_UTIL_H_ + +#include "avb_sysdeps.h" + +#ifdef __cplusplus +extern "C" { +#endif + +#define AVB_STRINGIFY(x) #x +#define AVB_TO_STRING(x) AVB_STRINGIFY(x) + +#ifdef AVB_ENABLE_DEBUG +/* Aborts the program if |expr| is false. + * + * This has no effect unless AVB_ENABLE_DEBUG is defined. + */ +#define avb_assert(expr) \ + do { \ + if (!(expr)) { \ + avb_fatal("assert fail: " #expr "\n"); \ + } \ + } while (0) +#else +#define avb_assert(expr) +#endif + +/* Aborts the program if reached. + * + * This has no effect unless AVB_ENABLE_DEBUG is defined. + */ +#ifdef AVB_ENABLE_DEBUG +#define avb_assert_not_reached() \ + do { \ + avb_fatal("assert_not_reached()\n"); \ + } while (0) +#else +#define avb_assert_not_reached() +#endif + +/* Aborts the program if |addr| is not word-aligned. + * + * This has no effect unless AVB_ENABLE_DEBUG is defined. + */ +#define avb_assert_word_aligned(addr) \ + avb_assert((((uintptr_t)addr) & (AVB_WORD_ALIGNMENT_SIZE - 1)) == 0) + +#ifdef AVB_ENABLE_DEBUG +/* Print functions, used for diagnostics. + * + * These have no effect unless AVB_ENABLE_DEBUG is defined. + */ +#define avb_debug(message) \ + do { \ + avb_print(__FILE__ ":" AVB_TO_STRING(__LINE__) ": DEBUG: "); \ + avb_print(message); \ + } while (0) +#define avb_debugv(message, ...) \ + do { \ + avb_print(__FILE__ ":" AVB_TO_STRING(__LINE__) ": DEBUG: "); \ + avb_printv(message, ##__VA_ARGS__); \ + } while (0) +#else +#define avb_debug(message) +#define avb_debugv(message, ...) +#endif + +/* Prints out a message. This is typically used if a runtime-error + * occurs. + */ +#define avb_error(message) \ + do { \ + avb_print(__FILE__ ":" AVB_TO_STRING(__LINE__) ": ERROR: "); \ + avb_print(message); \ + } while (0) +#define avb_errorv(message, ...) \ + do { \ + avb_print(__FILE__ ":" AVB_TO_STRING(__LINE__) ": ERROR: "); \ + avb_printv(message, ##__VA_ARGS__); \ + } while (0) + +/* Prints out a message and calls avb_abort(). + */ +#define avb_fatal(message) \ + do { \ + avb_print(__FILE__ ":" AVB_TO_STRING(__LINE__) ": FATAL: "); \ + avb_print(message); \ + avb_abort(); \ + } while (0) +#define avb_fatalv(message, ...) \ + do { \ + avb_print(__FILE__ ":" AVB_TO_STRING(__LINE__) ": FATAL: "); \ + avb_printv(message, ##__VA_ARGS__); \ + avb_abort(); \ + } while (0) + +/* Converts a 32-bit unsigned integer from big-endian to host byte order. */ +uint32_t avb_be32toh(uint32_t in) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Converts a 64-bit unsigned integer from big-endian to host byte order. */ +uint64_t avb_be64toh(uint64_t in) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Converts a 32-bit unsigned integer from host to big-endian byte order. */ +uint32_t avb_htobe32(uint32_t in) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Converts a 64-bit unsigned integer from host to big-endian byte order. */ +uint64_t avb_htobe64(uint64_t in) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Compare |n| bytes starting at |s1| with |s2| and return 0 if they + * match, 1 if they don't. Returns 0 if |n|==0, since no bytes + * mismatched. + * + * Time taken to perform the comparison is only dependent on |n| and + * not on the relationship of the match between |s1| and |s2|. + * + * Note that unlike avb_memcmp(), this only indicates inequality, not + * whether |s1| is less than or greater than |s2|. + */ +int avb_safe_memcmp(const void* s1, const void* s2, + size_t n) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Adds |value_to_add| to |value| with overflow protection. + * + * Returns false if the addition overflows, true otherwise. In either + * case, |value| is always modified. + */ +bool avb_safe_add_to(uint64_t* value, + uint64_t value_to_add) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Adds |a| and |b| with overflow protection, returning the value in + * |out_result|. + * + * It's permissible to pass NULL for |out_result| if you just want to + * check that the addition would not overflow. + * + * Returns false if the addition overflows, true otherwise. + */ +bool avb_safe_add(uint64_t* out_result, uint64_t a, + uint64_t b) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Checks if |num_bytes| data at |data| is a valid UTF-8 + * string. Returns true if valid UTF-8, false otherwise. + */ +bool avb_validate_utf8(const uint8_t* data, + size_t num_bytes) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Concatenates |str1| (of |str1_len| bytes) and |str2| (of |str2_len| + * bytes) and puts the result in |buf| which holds |buf_size| + * bytes. The result is also guaranteed to be NUL terminated. Fail if + * there is not enough room in |buf| for the resulting string plus + * terminating NUL byte. + * + * Returns true if the operation succeeds, false otherwise. + */ +bool avb_str_concat(char* buf, size_t buf_size, const char* str1, + size_t str1_len, const char* str2, size_t str2_len); + +/* Like avb_malloc_() but prints a error using avb_error() if memory + * allocation fails. + */ +void* avb_malloc(size_t size) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Like avb_malloc() but sets the memory with zeroes. */ +void* avb_calloc(size_t size) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Duplicates a NUL-terminated string. Returns NULL on OOM. */ +char* avb_strdup(const char* str) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Finds the first occurrence of |needle| in the string |haystack| + * where both strings are NUL-terminated strings. The terminating NUL + * bytes are not compared. + * + * Returns NULL if not found, otherwise points into |haystack| for the + * first occurrence of |needle|. + */ +const char* avb_strstr(const char* haystack, + const char* needle) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Finds the first occurrence of |str| in the NULL-terminated string + * array |strings|. Each element in |strings| must be + * NUL-terminated. The string given by |str| need not be + * NUL-terminated but its size must be given in |str_size|. + * + * Returns NULL if not found, otherwise points into |strings| for the + * first occurrence of |str|. + */ +const char* avb_strv_find_str(const char* const* strings, const char* str, + size_t str_size); + +/* Replaces all occurrences of |search| with |replace| in |str|. + * + * Returns a newly allocated string or NULL if out of memory. + */ +char* avb_replace(const char* str, const char* search, + const char* replace) AVB_ATTR_WARN_UNUSED_RESULT; + +/* Calculates the CRC-32 for data in |buf| of size |buf_size|. */ +uint32_t avb_crc32(const uint8_t* buf, size_t buf_size); + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_UTIL_H_ */ diff --git a/lib/avb/libavb/avb_vbmeta_image.c b/lib/avb/libavb/avb_vbmeta_image.c new file mode 100644 index 0000000..23607ed --- /dev/null +++ b/lib/avb/libavb/avb_vbmeta_image.c @@ -0,0 +1,562 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_vbmeta_image.h" +#include "avb_rsa.h" +#include "avb_sha.h" +#include "avb_util.h" + +/* NOTE: The PKC1-v1.5 padding is a blob of binary DER of ASN.1 and is + * obtained from section 5.2.2 of RFC 4880. + */ + +static const uint8_t + padding_RSA2048_SHA256[AVB_RSA2048_NUM_BYTES - AVB_SHA256_DIGEST_SIZE] = { + 0x00, 0x01, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0x00, 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, + 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20}; + +static const uint8_t + padding_RSA4096_SHA256[AVB_RSA4096_NUM_BYTES - AVB_SHA256_DIGEST_SIZE] = { + 0x00, 0x01, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0x00, 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, + 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20}; + +static const uint8_t + padding_RSA8192_SHA256[AVB_RSA8192_NUM_BYTES - AVB_SHA256_DIGEST_SIZE] = { + 0x00, 0x01, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0x00, 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, + 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20}; + +static const uint8_t + padding_RSA2048_SHA512[AVB_RSA2048_NUM_BYTES - AVB_SHA512_DIGEST_SIZE] = { + 0x00, 0x01, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0x00, 0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, 0x60, + 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, 0x05, 0x00, 0x04, 0x40}; + +static const uint8_t + padding_RSA4096_SHA512[AVB_RSA4096_NUM_BYTES - AVB_SHA512_DIGEST_SIZE] = { + 0x00, 0x01, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x30, 0x51, 0x30, + 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, + 0x05, 0x00, 0x04, 0x40}; + +static const uint8_t + padding_RSA8192_SHA512[AVB_RSA8192_NUM_BYTES - AVB_SHA512_DIGEST_SIZE] = { + 0x00, 0x01, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0x00, 0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, 0x60, + 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, 0x05, 0x00, 0x04, 0x40}; + +typedef struct { + const uint8_t* padding; + size_t padding_len; + size_t hash_len; +} AvbAlgorithmData; + +static AvbAlgorithmData algorithm_data[_AVB_ALGORITHM_NUM_TYPES] = { + /* AVB_ALGORITHM_TYPE_NONE */ + {.padding = NULL, .padding_len = 0, .hash_len = 0}, + /* AVB_ALGORITHM_TYPE_SHA256_RSA2048 */ + {.padding = padding_RSA2048_SHA256, + .padding_len = sizeof(padding_RSA2048_SHA256), + .hash_len = AVB_SHA256_DIGEST_SIZE}, + /* AVB_ALGORITHM_TYPE_SHA256_RSA4096 */ + {.padding = padding_RSA4096_SHA256, + .padding_len = sizeof(padding_RSA4096_SHA256), + .hash_len = AVB_SHA256_DIGEST_SIZE}, + /* AVB_ALGORITHM_TYPE_SHA256_RSA8192 */ + {.padding = padding_RSA8192_SHA256, + .padding_len = sizeof(padding_RSA8192_SHA256), + .hash_len = AVB_SHA256_DIGEST_SIZE}, + /* AVB_ALGORITHM_TYPE_SHA512_RSA2048 */ + {.padding = padding_RSA2048_SHA512, + .padding_len = sizeof(padding_RSA2048_SHA512), + .hash_len = AVB_SHA512_DIGEST_SIZE}, + /* AVB_ALGORITHM_TYPE_SHA512_RSA4096 */ + {.padding = padding_RSA4096_SHA512, + .padding_len = sizeof(padding_RSA4096_SHA512), + .hash_len = AVB_SHA512_DIGEST_SIZE}, + /* AVB_ALGORITHM_TYPE_SHA512_RSA8192 */ + {.padding = padding_RSA8192_SHA512, + .padding_len = sizeof(padding_RSA8192_SHA512), + .hash_len = AVB_SHA512_DIGEST_SIZE}, +}; + +AvbVBMetaVerifyResult avb_vbmeta_image_verify( + const uint8_t* data, size_t length, const uint8_t** out_public_key_data, + size_t* out_public_key_length) { + AvbVBMetaVerifyResult ret; + AvbVBMetaImageHeader h; + uint8_t* computed_hash; + AvbAlgorithmData* algorithm; + AvbSHA256Ctx sha256_ctx; + AvbSHA512Ctx sha512_ctx; + const uint8_t* header_block; + const uint8_t* authentication_block; + const uint8_t* auxiliary_block; + int verification_result; + + ret = AVB_VBMETA_VERIFY_RESULT_INVALID_VBMETA_HEADER; + + if (out_public_key_data != NULL) *out_public_key_data = NULL; + if (out_public_key_length != NULL) *out_public_key_length = 0; + + /* Ensure magic is correct. */ + if (avb_safe_memcmp(data, AVB_MAGIC, AVB_MAGIC_LEN) != 0) { + avb_error("Magic is incorrect.\n"); + goto out; + } + + /* Before we byteswap, ensure length is long enough. */ + if (length < sizeof(AvbVBMetaImageHeader)) { + avb_error("Length is smaller than header.\n"); + goto out; + } + avb_vbmeta_image_header_to_host_byte_order((const AvbVBMetaImageHeader*)data, + &h); + + /* Ensure we don't attempt to access any fields if the major version + * is not supported. + */ + if (h.header_version_major > AVB_MAJOR_VERSION) { + avb_error("No support for given major version.\n"); + goto out; + } + + /* Ensure inner block sizes are multiple of 64. */ + if ((h.authentication_data_block_size & 0x3f) != 0 || + (h.auxiliary_data_block_size & 0x3f) != 0) { + avb_error("Block size is not a multiple of 64.\n"); + goto out; + } + + /* Ensure block sizes all add up to at most |length|. */ + uint64_t block_total = sizeof(AvbVBMetaImageHeader); + if (!avb_safe_add_to(&block_total, h.authentication_data_block_size) || + !avb_safe_add_to(&block_total, h.auxiliary_data_block_size)) { + avb_error("Overflow while computing size of boot image.\n"); + goto out; + } + if (block_total > length) { + avb_error("Block sizes add up to more than given length.\n"); + goto out; + } + + uintptr_t data_ptr = (uintptr_t)data; + /* Ensure passed in memory doesn't wrap. */ + if (!avb_safe_add(NULL, (uint64_t)data_ptr, length)) { + avb_error("Boot image location and length mismatch.\n"); + goto out; + } + + /* Ensure hash and signature are entirely in the Authentication data block. */ + uint64_t hash_end; + if (!avb_safe_add(&hash_end, h.hash_offset, h.hash_size) || + hash_end > h.authentication_data_block_size) { + avb_error("Hash is not entirely in its block.\n"); + goto out; + } + uint64_t signature_end; + if (!avb_safe_add(&signature_end, h.signature_offset, h.signature_size) || + signature_end > h.authentication_data_block_size) { + avb_error("Signature is not entirely in its block.\n"); + goto out; + } + + /* Ensure public key is entirely in the Auxiliary data block. */ + uint64_t pubkey_end; + if (!avb_safe_add(&pubkey_end, h.public_key_offset, h.public_key_size) || + pubkey_end > h.auxiliary_data_block_size) { + avb_error("Public key is not entirely in its block.\n"); + goto out; + } + + /* Ensure algorithm field is supported. */ + if (h.algorithm_type >= _AVB_ALGORITHM_NUM_TYPES) { + avb_error("Invalid or unknown algorithm.\n"); + goto out; + } + algorithm = &algorithm_data[h.algorithm_type]; + + /* Bail early if there's no hash or signature. */ + if (h.algorithm_type == AVB_ALGORITHM_TYPE_NONE) { + ret = AVB_VBMETA_VERIFY_RESULT_OK_NOT_SIGNED; + goto out; + } + + /* Bail if the embedded hash size doesn't match the chosen algorithm. */ + if (h.hash_size != algorithm->hash_len) { + avb_error("Embedded hash has wrong size.\n"); + goto out; + } + + /* No overflow checks needed from here-on after since all block + * sizes and offsets have been verified above. + */ + + header_block = data; + authentication_block = header_block + sizeof(AvbVBMetaImageHeader); + auxiliary_block = authentication_block + h.authentication_data_block_size; + + switch (h.algorithm_type) { + /* Explicit fall-through: */ + case AVB_ALGORITHM_TYPE_SHA256_RSA2048: + case AVB_ALGORITHM_TYPE_SHA256_RSA4096: + case AVB_ALGORITHM_TYPE_SHA256_RSA8192: + avb_sha256_init(&sha256_ctx); + avb_sha256_update(&sha256_ctx, header_block, + sizeof(AvbVBMetaImageHeader)); + avb_sha256_update(&sha256_ctx, auxiliary_block, + h.auxiliary_data_block_size); + computed_hash = avb_sha256_final(&sha256_ctx); + break; + /* Explicit fall-through: */ + case AVB_ALGORITHM_TYPE_SHA512_RSA2048: + case AVB_ALGORITHM_TYPE_SHA512_RSA4096: + case AVB_ALGORITHM_TYPE_SHA512_RSA8192: + avb_sha512_init(&sha512_ctx); + avb_sha512_update(&sha512_ctx, header_block, + sizeof(AvbVBMetaImageHeader)); + avb_sha512_update(&sha512_ctx, auxiliary_block, + h.auxiliary_data_block_size); + computed_hash = avb_sha512_final(&sha512_ctx); + break; + default: + avb_error("Unknown algorithm.\n"); + goto out; + } + + if (avb_safe_memcmp(authentication_block + h.hash_offset, computed_hash, + h.hash_size) != 0) { + avb_error("Hash does not match!\n"); + ret = AVB_VBMETA_VERIFY_RESULT_HASH_MISMATCH; + goto out; + } + + verification_result = + avb_rsa_verify(auxiliary_block + h.public_key_offset, h.public_key_size, + authentication_block + h.signature_offset, + h.signature_size, authentication_block + h.hash_offset, + h.hash_size, algorithm->padding, algorithm->padding_len); + + if (verification_result == 0) { + ret = AVB_VBMETA_VERIFY_RESULT_SIGNATURE_MISMATCH; + goto out; + } + + if (out_public_key_data != NULL) + *out_public_key_data = auxiliary_block + h.public_key_offset; + if (out_public_key_length != NULL) *out_public_key_length = h.public_key_size; + + ret = AVB_VBMETA_VERIFY_RESULT_OK; + +out: + return ret; +} + +void avb_vbmeta_image_header_to_host_byte_order(const AvbVBMetaImageHeader* src, + AvbVBMetaImageHeader* dest) { + avb_memcpy(dest, src, sizeof(AvbVBMetaImageHeader)); + + dest->header_version_major = avb_be32toh(dest->header_version_major); + dest->header_version_minor = avb_be32toh(dest->header_version_minor); + + dest->authentication_data_block_size = + avb_be64toh(dest->authentication_data_block_size); + dest->auxiliary_data_block_size = + avb_be64toh(dest->auxiliary_data_block_size); + + dest->algorithm_type = avb_be32toh(dest->algorithm_type); + + dest->hash_offset = avb_be64toh(dest->hash_offset); + dest->hash_size = avb_be64toh(dest->hash_size); + + dest->signature_offset = avb_be64toh(dest->signature_offset); + dest->signature_size = avb_be64toh(dest->signature_size); + + dest->public_key_offset = avb_be64toh(dest->public_key_offset); + dest->public_key_size = avb_be64toh(dest->public_key_size); + + dest->descriptors_offset = avb_be64toh(dest->descriptors_offset); + dest->descriptors_size = avb_be64toh(dest->descriptors_size); + + dest->rollback_index = avb_be64toh(dest->rollback_index); +} diff --git a/lib/avb/libavb/avb_vbmeta_image.h b/lib/avb/libavb/avb_vbmeta_image.h new file mode 100644 index 0000000..25d3689 --- /dev/null +++ b/lib/avb/libavb/avb_vbmeta_image.h @@ -0,0 +1,240 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb.h instead." +#endif + +#ifndef AVB_VBMETA_IMAGE_H_ +#define AVB_VBMETA_IMAGE_H_ + +#include "avb_sysdeps.h" + +#ifdef __cplusplus +extern "C" { +#endif + +#include "avb_crypto.h" +#include "avb_descriptor.h" + +/* Size of the vbmeta image header. */ +#define AVB_VBMETA_IMAGE_HEADER_SIZE 256 + +/* Magic for the vbmeta image header. */ +#define AVB_MAGIC "AVB0" +#define AVB_MAGIC_LEN 4 + +/* The current MAJOR and MINOR versions used - keep in sync with avbtool. */ +#define AVB_MAJOR_VERSION 1 +#define AVB_MINOR_VERSION 0 + +/* Binary format for header of the vbmeta image. + * + * The vbmeta image consists of three blocks: + * + * +-----------------------------------------+ + * | Header data - fixed size | + * +-----------------------------------------+ + * | Authentication data - variable size | + * +-----------------------------------------+ + * | Auxiliary data - variable size | + * +-----------------------------------------+ + * + * The "Header data" block is described by this struct and is always + * |AVB_VBMETA_IMAGE_HEADER_SIZE| bytes long. + * + * The "Authentication data" block is |authentication_data_block_size| + * bytes long and contains the hash and signature used to authenticate + * the vbmeta image. The type of the hash and signature is defined by + * the |algorithm_type| field. + * + * The "Auxiliary data" is |auxiliary_data_block_size| bytes long and + * contains the auxiliary data including the public key used to make + * the signature and descriptors. + * + * The public key is at offset |public_key_offset| with size + * |public_key_size| in this block. The size of the public key data is + * defined by the |algorithm_type| field. The format of the public key + * data is described in the |AvbRSAPublicKeyHeader| struct. + * + * The descriptors starts at |descriptors_offset| from the beginning + * of the "Auxiliary Data" block and take up |descriptors_size| + * bytes. Each descriptor is stored as a |AvbDescriptor| with tag and + * number of bytes following. The number of descriptors can be + * determined by walking this data until |descriptors_size| is + * exhausted. + * + * The size of each of the "Authentication data" and "Auxiliary data" + * blocks must be divisible by 64. This is to ensure proper alignment. + * + * Descriptors are free-form blocks stored in a part of the vbmeta + * image subject to the same integrity checks as the rest of the + * image. See the documentation for |AvbDescriptor| for well-known + * descriptors. See avb_descriptor_foreach() for a convenience + * function to iterate over descriptors. + * + * This struct is versioned, see the |header_version_major| and + * |header_version_minor| fields. Compatibility is guaranteed only + * within the same major version. + * + * All fields are stored in network byte order when serialized. To + * generate a copy with fields swapped to native byte order, use the + * function avb_vbmeta_image_header_to_host_byte_order(). + * + * Before reading and/or using any of this data, you MUST verify it + * using avb_vbmeta_image_verify() and reject it unless it's signed by + * a known good public key. + */ +typedef struct AvbVBMetaImageHeader { + /* 0: Four bytes equal to "AVB0" (AVB_MAGIC). */ + uint8_t magic[AVB_MAGIC_LEN]; + /* 4: The major version of the vbmeta image header. */ + uint32_t header_version_major; + /* 8: The minor version of the vbmeta image header. */ + uint32_t header_version_minor; + + /* 12: The size of the signature block. */ + uint64_t authentication_data_block_size; + /* 20: The size of the auxiliary data block. */ + uint64_t auxiliary_data_block_size; + + /* 28: The verification algorithm used, see |AvbAlgorithmType| enum. */ + uint32_t algorithm_type; + + /* 32: Offset into the "Authentication data" block of hash data. */ + uint64_t hash_offset; + /* 40: Length of the hash data. */ + uint64_t hash_size; + + /* 48: Offset into the "Authentication data" block of signature data. */ + uint64_t signature_offset; + /* 56: Length of the signature data. */ + uint64_t signature_size; + + /* 64: Offset into the "Auxiliary data" block of public key data. */ + uint64_t public_key_offset; + /* 72: Length of the public key data. */ + uint64_t public_key_size; + + /* 80: Offset into the "Auxiliary data" block of descriptor data. */ + uint64_t descriptors_offset; + /* 88: Length of descriptor data. */ + uint64_t descriptors_size; + + /* 96: The rollback index which can be used to prevent rollback to + * older versions. + */ + uint64_t rollback_index; + + /* 104: Padding to ensure struct is size AVB_VBMETA_IMAGE_HEADER_SIZE + * bytes. This must be set to zeroes. + */ + uint8_t reserved[152]; +} AVB_ATTR_PACKED AvbVBMetaImageHeader; + +/* Copies |src| to |dest|, byte-swapping fields in the process. + * + * Make sure you've verified |src| using avb_vbmeta_image_verify() + * before accessing the data and/or using this function. + */ +void avb_vbmeta_image_header_to_host_byte_order(const AvbVBMetaImageHeader* src, + AvbVBMetaImageHeader* dest); + +/* Return codes used in avb_vbmeta_image_verify(). + * + * AVB_VBMETA_VERIFY_RESULT_OK is returned if the vbmeta image header + * is valid, the hash is correct and the signature is correct. Keep in + * mind that you still need to check that you know the public key used + * to sign the image, see avb_vbmeta_image_verify() for details. + * + * AVB_VBMETA_VERIFY_RESULT_OK_NOT_SIGNED is returned if the vbmeta + * image header is valid but there is no signature or hash. + * + * AVB_VERIFY_INVALID_VBMETA_HEADER is returned if the header of + * the vbmeta image is invalid, for example, invalid magic or + * inconsistent data. + * + * AVB_VERIFY_HASH_MISMATCH is returned if the hash stored in the + * "Authentication data" block does not match the calculated hash. + * + * AVB_VERIFY_SIGNATURE_MISMATCH is returned if the signature stored + * in the "Authentication data" block is invalid or doesn't match the + * public key stored in the vbmeta image. + */ +typedef enum { + AVB_VBMETA_VERIFY_RESULT_OK, + AVB_VBMETA_VERIFY_RESULT_OK_NOT_SIGNED, + AVB_VBMETA_VERIFY_RESULT_INVALID_VBMETA_HEADER, + AVB_VBMETA_VERIFY_RESULT_HASH_MISMATCH, + AVB_VBMETA_VERIFY_RESULT_SIGNATURE_MISMATCH, +} AvbVBMetaVerifyResult; + +/* Checks that vbmeta image at |data| of size |length| is a valid + * vbmeta image. The complete contents of the vbmeta image must be + * passed in. It's fine if |length| is bigger than the actual image, + * typically callers of this function will load the entire contents of + * the 'vbmeta_a' or 'vbmeta_b' partition and pass in its length (for + * example, 1 MiB). + * + * See the |AvbVBMetaImageHeader| struct for information about the + * three blocks (header, authentication, auxiliary) that make up a + * vbmeta image. + * + * If the function returns |AVB_VBMETA_VERIFY_RESULT_OK| and + * |out_public_key_data| is non-NULL, it will be set to point inside + * |data| for where the serialized public key data is stored and + * |out_public_key_length|, if non-NULL, will be set to the length of + * the public key data. + * + * See the |AvbVBMetaVerifyResult| enum for possible return values. + * + * VERY IMPORTANT: + * + * 1. Even if |AVB_VBMETA_VERIFY_RESULT_OK| is returned, you still + * need to check that the public key embedded in the image + * matches a known key! You can use 'avbtool extract_public_key' + * to extract the key (at build time, then store it along your + * code) and compare it to what is returned in + * |out_public_key_data|. + * + * 2. You need to check the |rollback_index| field against a stored + * value in NVRAM and reject the vbmeta image if the value in + * NVRAM is bigger than |rollback_index|. You must also update + * the value stored in NVRAM to the smallest value of + * |rollback_index| field from boot images in all bootable and + * authentic slots marked as GOOD. + * + * This is a low-level function to only verify the vbmeta data - you + * are likely looking for avb_slot_verify() instead for verifying + * integrity data for a whole set of partitions. + */ +AvbVBMetaVerifyResult avb_vbmeta_image_verify( + const uint8_t* data, size_t length, const uint8_t** out_public_key_data, + size_t* out_public_key_length) AVB_ATTR_WARN_UNUSED_RESULT; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_VBMETA_IMAGE_H_ */ diff --git a/lib/avb/libavb/libavb.h b/lib/avb/libavb/libavb.h new file mode 100644 index 0000000..b74307c --- /dev/null +++ b/lib/avb/libavb/libavb.h @@ -0,0 +1,49 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#ifndef LIBAVB_H_ +#define LIBAVB_H_ + +/* The AVB_INSIDE_LIBAVB_H preprocessor symbol is used to enforce + * library users to include only this file. All public interfaces, and + * only public interfaces, must be included here. + */ + +#define AVB_INSIDE_LIBAVB_H +#include "avb_chain_partition_descriptor.h" +#include "avb_crypto.h" +#include "avb_descriptor.h" +#include "avb_footer.h" +#include "avb_hash_descriptor.h" +#include "avb_hashtree_descriptor.h" +#include "avb_kernel_cmdline_descriptor.h" +#include "avb_ops.h" +#include "avb_property_descriptor.h" +#include "avb_slot_verify.h" +#include "avb_sysdeps.h" +#include "avb_util.h" +#include "avb_vbmeta_image.h" +#undef AVB_INSIDE_LIBAVB_H + +#endif /* LIBAVB_H_ */ diff --git a/lib/avb/libavb_ab/Makefile b/lib/avb/libavb_ab/Makefile new file mode 100644 index 0000000..f22d0ed --- /dev/null +++ b/lib/avb/libavb_ab/Makefile @@ -0,0 +1,2 @@ +ccflags-y += -DAVB_COMPILATION +obj-y += avb_ab_flow.o diff --git a/lib/avb/libavb_ab/avb_ab_flow.c b/lib/avb/libavb_ab/avb_ab_flow.c new file mode 100644 index 0000000..da8e4ea --- /dev/null +++ b/lib/avb/libavb_ab/avb_ab_flow.c @@ -0,0 +1,431 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "avb_ab_flow.h" + +bool avb_ab_data_verify_and_byteswap(const AvbABData* src, AvbABData* dest) { + /* Ensure magic is correct. */ + if (avb_safe_memcmp(src->magic, AVB_AB_MAGIC, AVB_AB_MAGIC_LEN) != 0) { + avb_error("Magic is incorrect.\n"); + return false; + } + + avb_memcpy(dest, src, sizeof(AvbABData)); + dest->crc32 = avb_be32toh(dest->crc32); + + /* Ensure we don't attempt to access any fields if the major version + * is not supported. + */ + if (dest->version_major > AVB_AB_MAJOR_VERSION) { + avb_error("No support for given major version.\n"); + return false; + } + + /* Bail if CRC32 doesn't match. */ + if (dest->crc32 != + avb_crc32((const uint8_t*)dest, sizeof(AvbABData) - sizeof(uint32_t))) { + avb_error("CRC32 does not match.\n"); + return false; + } + + return true; +} + +void avb_ab_data_update_crc_and_byteswap(const AvbABData* src, + AvbABData* dest) { + avb_memcpy(dest, src, sizeof(AvbABData)); + dest->crc32 = avb_htobe32( + avb_crc32((const uint8_t*)dest, sizeof(AvbABData) - sizeof(uint32_t))); +} + +void avb_ab_data_init(AvbABData* data) { + avb_memset(data, '\0', sizeof(AvbABData)); + avb_memcpy(data->magic, AVB_AB_MAGIC, AVB_AB_MAGIC_LEN); + data->version_major = AVB_AB_MAJOR_VERSION; + data->version_minor = AVB_AB_MINOR_VERSION; + data->slots[0].priority = AVB_AB_MAX_PRIORITY; + data->slots[0].tries_remaining = AVB_AB_MAX_TRIES_REMAINING; + data->slots[0].successful_boot = 0; + data->slots[1].priority = AVB_AB_MAX_PRIORITY - 1; + data->slots[1].tries_remaining = AVB_AB_MAX_TRIES_REMAINING; + data->slots[1].successful_boot = 0; +} + +/* The AvbABData struct is stored 2048 bytes into the 'misc' partition + * following the 'struct bootloader_message' field. The struct is + * compatible with the guidelines in bootable/recovery/bootloader.h - + * e.g. it is stored in the |slot_suffix| field, starts with a + * NUL-byte, and is 32 bytes long. + */ +#define AB_METADATA_MISC_PARTITION_OFFSET 2048 + +AvbIOResult avb_ab_data_read(AvbABOps* ab_ops, AvbABData* data) { + AvbOps* ops = &(ab_ops->ops); + AvbABData serialized; + AvbIOResult io_ret; + size_t num_bytes_read; + + io_ret = + ops->read_from_partition(ops, "misc", AB_METADATA_MISC_PARTITION_OFFSET, + sizeof(AvbABData), &serialized, &num_bytes_read); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + return AVB_IO_RESULT_ERROR_OOM; + } else if (io_ret != AVB_IO_RESULT_OK || + num_bytes_read != sizeof(AvbABData)) { + avb_error("Error reading A/B metadata.\n"); + return AVB_IO_RESULT_ERROR_IO; + } + + if (!avb_ab_data_verify_and_byteswap(&serialized, data)) { + avb_error( + "Error validating A/B metadata from disk. " + "Resetting and writing new A/B metadata to disk.\n"); + avb_ab_data_init(data); + return avb_ab_data_write(ab_ops, data); + } + + return AVB_IO_RESULT_OK; +} + +AvbIOResult avb_ab_data_write(AvbABOps* ab_ops, const AvbABData* data) { + AvbOps* ops = &(ab_ops->ops); + AvbABData serialized; + AvbIOResult io_ret; + + avb_ab_data_update_crc_and_byteswap(data, &serialized); + io_ret = + ops->write_to_partition(ops, "misc", AB_METADATA_MISC_PARTITION_OFFSET, + sizeof(AvbABData), &serialized); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + return AVB_IO_RESULT_ERROR_OOM; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_error("Error writing A/B metadata.\n"); + return AVB_IO_RESULT_ERROR_IO; + } + return AVB_IO_RESULT_OK; +} + +static bool slot_is_bootable(AvbABSlotData* slot) { + return slot->priority > 0 && + (slot->successful_boot || (slot->tries_remaining > 0)); +} + +static void slot_set_unbootable(AvbABSlotData* slot) { + slot->priority = 0; + slot->tries_remaining = 0; + slot->successful_boot = 0; +} + +/* Ensure all unbootable and/or illegal states are marked as the + * canonical 'unbootable' state, e.g. priority=0, tries_remaining=0, + * and successful_boot=0. + */ +static void slot_normalize(AvbABSlotData* slot) { + if (slot->priority > 0) { + if (slot->tries_remaining == 0 && !slot->successful_boot) { + /* We've exhausted all tries -> unbootable. */ + slot_set_unbootable(slot); + } + if (slot->tries_remaining > 0 && slot->successful_boot) { + /* Illegal state - avb_ab_mark_slot_successful() will clear + * tries_remaining when setting successful_boot. + */ + slot_set_unbootable(slot); + } + } else { + slot_set_unbootable(slot); + } +} + +static const char* slot_suffixes[2] = {"_a", "_b"}; + +/* Helper function to load metadata - returns AVB_IO_RESULT_OK on + * success, error code otherwise. + */ +static AvbIOResult load_metadata(AvbABOps* ab_ops, AvbABData* ab_data, + AvbABData* ab_data_orig) { + AvbIOResult io_ret; + + io_ret = ab_ops->read_ab_metadata(ab_ops, ab_data); + if (io_ret != AVB_IO_RESULT_OK) { + avb_error("I/O error while loading A/B metadata.\n"); + return io_ret; + } + *ab_data_orig = *ab_data; + + /* Ensure data is normalized, e.g. illegal states will be marked as + * unbootable and all unbootable states are represented with + * (priority=0, tries_remaining=0, successful_boot=0). + */ + slot_normalize(&ab_data->slots[0]); + slot_normalize(&ab_data->slots[1]); + return AVB_IO_RESULT_OK; +} + +/* Writes A/B metadata to disk only if it has changed - returns + * AVB_IO_RESULT_OK on success, error code otherwise. + */ +static AvbIOResult save_metadata_if_changed(AvbABOps* ab_ops, + AvbABData* ab_data, + AvbABData* ab_data_orig) { + if (avb_safe_memcmp(ab_data, ab_data_orig, sizeof(AvbABData)) != 0) { + avb_debug("Writing A/B metadata to disk.\n"); + return ab_ops->write_ab_metadata(ab_ops, ab_data); + } + return AVB_IO_RESULT_OK; +} + +AvbABFlowResult avb_ab_flow(AvbABOps* ab_ops, + const char* const* requested_partitions, + AvbSlotVerifyData** out_data) { + AvbOps* ops = &(ab_ops->ops); + AvbSlotVerifyData* slot_data[2] = {NULL, NULL}; + AvbSlotVerifyData* data = NULL; + AvbABFlowResult ret; + AvbABData ab_data, ab_data_orig; + size_t slot_index_to_boot, n; + AvbIOResult io_ret; + + io_ret = load_metadata(ab_ops, &ab_data, &ab_data_orig); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_AB_FLOW_RESULT_ERROR_OOM; + goto out; + } else if (io_ret != AVB_IO_RESULT_OK) { + ret = AVB_AB_FLOW_RESULT_ERROR_IO; + goto out; + } + + /* Validate all bootable slots. */ + for (n = 0; n < 2; n++) { + if (slot_is_bootable(&ab_data.slots[n])) { + AvbSlotVerifyResult verify_result; + verify_result = avb_slot_verify(ops, requested_partitions, + slot_suffixes[n], &slot_data[n]); + if (verify_result != AVB_SLOT_VERIFY_RESULT_OK) { + if (verify_result == AVB_SLOT_VERIFY_RESULT_ERROR_OOM) { + ret = AVB_AB_FLOW_RESULT_ERROR_OOM; + goto out; + } + if (verify_result == AVB_SLOT_VERIFY_RESULT_ERROR_IO) { + ret = AVB_AB_FLOW_RESULT_ERROR_IO; + goto out; + } + avb_errorv("Error verifying slot ", slot_suffixes[n], " with result ", + avb_slot_verify_result_to_string(verify_result), + " - setting unbootable.\n", NULL); + slot_set_unbootable(&ab_data.slots[n]); + } + } + } + + if (slot_is_bootable(&ab_data.slots[0]) && + slot_is_bootable(&ab_data.slots[1])) { + if (ab_data.slots[1].priority > ab_data.slots[0].priority) { + slot_index_to_boot = 1; + } else { + slot_index_to_boot = 0; + } + } else if (slot_is_bootable(&ab_data.slots[0])) { + slot_index_to_boot = 0; + } else if (slot_is_bootable(&ab_data.slots[1])) { + slot_index_to_boot = 1; + } else { + /* No bootable slots! */ + avb_error("No bootable slots found.\n"); + ret = AVB_AB_FLOW_RESULT_ERROR_NO_BOOTABLE_SLOTS; + goto out; + } + + /* Update stored rollback index such that the stored rollback index + * is the largest value supporting all currently bootable slots. Do + * this for every rollback index slot. + */ + for (n = 0; n < AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_SLOTS; n++) { + uint64_t rollback_index_value = 0; + + if (slot_data[0] != NULL && slot_data[1] != NULL) { + uint64_t a_rollback_index = slot_data[0]->rollback_indexes[n]; + uint64_t b_rollback_index = slot_data[1]->rollback_indexes[n]; + rollback_index_value = + (a_rollback_index < b_rollback_index ? a_rollback_index + : b_rollback_index); + } else if (slot_data[0] != NULL) { + rollback_index_value = slot_data[0]->rollback_indexes[n]; + } else if (slot_data[1] != NULL) { + rollback_index_value = slot_data[1]->rollback_indexes[n]; + } + + if (rollback_index_value != 0) { + uint64_t current_rollback_index_value; + io_ret = ops->read_rollback_index(ops, n, ¤t_rollback_index_value); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_AB_FLOW_RESULT_ERROR_OOM; + goto out; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_error("Error getting rollback index for slot.\n"); + ret = AVB_AB_FLOW_RESULT_ERROR_IO; + goto out; + } + if (current_rollback_index_value != rollback_index_value) { + io_ret = ops->write_rollback_index(ops, n, rollback_index_value); + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_AB_FLOW_RESULT_ERROR_OOM; + goto out; + } else if (io_ret != AVB_IO_RESULT_OK) { + avb_error("Error setting stored rollback index.\n"); + ret = AVB_AB_FLOW_RESULT_ERROR_IO; + goto out; + } + } + } + } + + /* Finally, select this slot. */ + avb_assert(slot_data[slot_index_to_boot] != NULL); + data = slot_data[slot_index_to_boot]; + slot_data[slot_index_to_boot] = NULL; + ret = AVB_AB_FLOW_RESULT_OK; + + /* ... and decrement tries remaining, if applicable. */ + if (!ab_data.slots[slot_index_to_boot].successful_boot && + ab_data.slots[slot_index_to_boot].tries_remaining > 0) { + ab_data.slots[slot_index_to_boot].tries_remaining -= 1; + } + +out: + io_ret = save_metadata_if_changed(ab_ops, &ab_data, &ab_data_orig); + if (io_ret != AVB_IO_RESULT_OK) { + if (io_ret == AVB_IO_RESULT_ERROR_OOM) { + ret = AVB_AB_FLOW_RESULT_ERROR_OOM; + } else { + ret = AVB_AB_FLOW_RESULT_ERROR_IO; + } + if (data != NULL) { + avb_slot_verify_data_free(data); + data = NULL; + } + } + + for (n = 0; n < 2; n++) { + if (slot_data[n] != NULL) { + avb_slot_verify_data_free(slot_data[n]); + } + } + + if (out_data != NULL) { + *out_data = data; + } else { + if (data != NULL) { + avb_slot_verify_data_free(data); + } + } + + return ret; +} + +AvbIOResult avb_ab_mark_slot_active(AvbABOps* ab_ops, + unsigned int slot_number) { + AvbABData ab_data, ab_data_orig; + unsigned int other_slot_number; + AvbIOResult ret; + + avb_assert(slot_number < 2); + + ret = load_metadata(ab_ops, &ab_data, &ab_data_orig); + if (ret != AVB_IO_RESULT_OK) { + goto out; + } + + /* Make requested slot top priority, unsuccessful, and with max tries. */ + ab_data.slots[slot_number].priority = AVB_AB_MAX_PRIORITY; + ab_data.slots[slot_number].tries_remaining = AVB_AB_MAX_TRIES_REMAINING; + ab_data.slots[slot_number].successful_boot = 0; + + /* Ensure other slot doesn't have as high a priority. */ + other_slot_number = 1 - slot_number; + if (ab_data.slots[other_slot_number].priority == AVB_AB_MAX_PRIORITY) { + ab_data.slots[other_slot_number].priority = AVB_AB_MAX_PRIORITY - 1; + } + + ret = AVB_IO_RESULT_OK; + +out: + if (ret == AVB_IO_RESULT_OK) { + ret = save_metadata_if_changed(ab_ops, &ab_data, &ab_data_orig); + } + return ret; +} + +AvbIOResult avb_ab_mark_slot_unbootable(AvbABOps* ab_ops, + unsigned int slot_number) { + AvbABData ab_data, ab_data_orig; + AvbIOResult ret; + + avb_assert(slot_number < 2); + + ret = load_metadata(ab_ops, &ab_data, &ab_data_orig); + if (ret != AVB_IO_RESULT_OK) { + goto out; + } + + slot_set_unbootable(&ab_data.slots[slot_number]); + + ret = AVB_IO_RESULT_OK; + +out: + if (ret == AVB_IO_RESULT_OK) { + ret = save_metadata_if_changed(ab_ops, &ab_data, &ab_data_orig); + } + return ret; +} + +AvbIOResult avb_ab_mark_slot_successful(AvbABOps* ab_ops, + unsigned int slot_number) { + AvbABData ab_data, ab_data_orig; + AvbIOResult ret; + + avb_assert(slot_number < 2); + + ret = load_metadata(ab_ops, &ab_data, &ab_data_orig); + if (ret != AVB_IO_RESULT_OK) { + goto out; + } + + if (!slot_is_bootable(&ab_data.slots[slot_number])) { + avb_error("Cannot mark unbootable slot as successful.\n"); + ret = AVB_IO_RESULT_OK; + goto out; + } + + ab_data.slots[slot_number].tries_remaining = 0; + ab_data.slots[slot_number].successful_boot = 1; + + ret = AVB_IO_RESULT_OK; + +out: + if (ret == AVB_IO_RESULT_OK) { + ret = save_metadata_if_changed(ab_ops, &ab_data, &ab_data_orig); + } + return ret; +} diff --git a/lib/avb/libavb_ab/avb_ab_flow.h b/lib/avb/libavb_ab/avb_ab_flow.h new file mode 100644 index 0000000..21f680a93 --- /dev/null +++ b/lib/avb/libavb_ab/avb_ab_flow.h @@ -0,0 +1,226 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_AB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb/libavb_ab.h instead." +#endif + +#ifndef AVB_AB_FLOW_H_ +#define AVB_AB_FLOW_H_ + +#include "avb_ab_ops.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* Magic for the A/B struct when serialized. */ +#define AVB_AB_MAGIC "\0AB0" +#define AVB_AB_MAGIC_LEN 4 + +/* Versioning for the on-disk A/B metadata - keep in sync with avbtool. */ +#define AVB_AB_MAJOR_VERSION 1 +#define AVB_AB_MINOR_VERSION 0 + +/* Size of AvbABData struct. */ +#define AVB_AB_DATA_SIZE 32 + +/* Maximum values for slot data */ +#define AVB_AB_MAX_PRIORITY 15 +#define AVB_AB_MAX_TRIES_REMAINING 7 + +/* Struct used for recording per-slot metadata. + * + * When serialized, data is stored in network byte-order. + */ +typedef struct AvbABSlotData { + /* Slot priority. Valid values range from 0 to AVB_AB_MAX_PRIORITY, + * both inclusive with 1 being the lowest and AVB_AB_MAX_PRIORITY + * being the highest. The special value 0 is used to indicate the + * slot is unbootable. + */ + uint8_t priority; + + /* Number of times left attempting to boot this slot ranging from 0 + * to AVB_AB_MAX_TRIES_REMAINING. + */ + uint8_t tries_remaining; + + /* Non-zero if this slot has booted successfully, 0 otherwise. */ + uint8_t successful_boot; + + /* Reserved for future use. */ + uint8_t reserved[1]; +} AVB_ATTR_PACKED AvbABSlotData; + +/* Struct used for recording A/B metadata. + * + * When serialized, data is stored in network byte-order. + */ +typedef struct AvbABData { + /* Magic number used for identification - see AVB_AB_MAGIC. */ + uint8_t magic[AVB_AB_MAGIC_LEN]; + + /* Version of on-disk struct - see AVB_AB_{MAJOR,MINOR}_VERSION. */ + uint8_t version_major; + uint8_t version_minor; + + /* Padding to ensure |slots| field start eight bytes in. */ + uint8_t reserved1[2]; + + /* Per-slot metadata. */ + AvbABSlotData slots[2]; + + /* Reserved for future use. */ + uint8_t reserved2[12]; + + /* CRC32 of all 28 bytes preceding this field. */ + uint32_t crc32; +} AVB_ATTR_PACKED AvbABData; + +/* Copies |src| to |dest|, byte-swapping fields in the + * process. Returns false if the data is invalid (e.g. wrong magic, + * wrong CRC32 etc.), true otherwise. + */ +bool avb_ab_data_verify_and_byteswap(const AvbABData* src, AvbABData* dest); + +/* Copies |src| to |dest|, byte-swapping fields in the process. Also + * updates the |crc32| field in |dest|. + */ +void avb_ab_data_update_crc_and_byteswap(const AvbABData* src, AvbABData* dest); + +/* Initializes |data| such that it has two slots and both slots have + * maximum tries remaining. The CRC is not set. + */ +void avb_ab_data_init(AvbABData* data); + +/* Reads A/B metadata from the 'misc' partition using |ops|. Returned + * data is properly byteswapped. Returns AVB_IO_RESULT_OK on + * success, error code otherwise. + * + * If the data read from disk is invalid (e.g. wrong magic or CRC + * checksum failure), the metadata will be reset using + * avb_ab_data_init() and then written to disk. + */ +AvbIOResult avb_ab_data_read(AvbABOps* ab_ops, AvbABData* data); + +/* Writes A/B metadata to the 'misc' partition using |ops|. This will + * byteswap and update the CRC as needed. Returns AVB_IO_RESULT_OK on + * success, error code otherwise. + */ +AvbIOResult avb_ab_data_write(AvbABOps* ab_ops, const AvbABData* data); + +/* Return codes used in avb_ab_flow(), see that function for + * documentation of each value. + */ +typedef enum { + AVB_AB_FLOW_RESULT_OK, + AVB_AB_FLOW_RESULT_ERROR_OOM, + AVB_AB_FLOW_RESULT_ERROR_IO, + AVB_AB_FLOW_RESULT_ERROR_NO_BOOTABLE_SLOTS +} AvbABFlowResult; + +/* High-level function to select a slot to boot. The following + * algorithm is used: + * + * 1. A/B metadata is loaded and validated using the + * read_ab_metadata() operation. Typically this means it's read from + * the 'misc' partition and if it's invalid then it's reset using + * avb_ab_data_init() and this reset metadata is returned. + * + * 2. All bootable slots listed in the A/B metadata are verified using + * avb_slot_verify(). If a slot fails verification, it will be marked + * as unbootable in the A/B metadata and the metadata will be saved to + * disk before returning. + * + * 3. If there are no bootable slots, the value + * AVB_AB_FLOW_RESULT_ERROR_NO_BOOTABLE_SLOTS is returned. + * + * 4. For each bootable slot, the Stored Rollback Indexes are updated + * such that for each rollback index slot, the Stored Rollback Index + * is the largest number smaller than or equal to the Rollback Index + * of each slot. + * + * 5. The bootable slot with the highest priority is selected and + * returned in |out_data|. If this slot is already marked as + * successful, the A/B metadata is not modified. However, if the slot + * is not marked as bootable its |tries_remaining| count is + * decremented and the A/B metadata is saved to disk before returning. + * In either case the value AVB_AB_FLOW_RESULT_OK is returning. + * + * The partitions to load is given in |requested_partitions| as a + * NULL-terminated array of NUL-terminated strings. Typically the + * |requested_partitions| array only contains a single item for the + * boot partition, 'boot'. + * + * If an I/O operation - such as loading/saving metadata or checking + * rollback indexes - fail, the value AVB_AB_FLOW_RESULT_ERROR_IO is + * returned. + * + * If memory allocation fails, AVB_AB_FLOW_RESULT_ERROR_OOM is + * returned. + * + * Reasonable behavior for handling AVB_AB_FLOW_RESULT_ERROR_NO_BOOTABLE_SLOTS + * is to initiate device recovery (which is device-dependent). + */ +AvbABFlowResult avb_ab_flow(AvbABOps* ab_ops, + const char* const* requested_partitions, + AvbSlotVerifyData** out_data); + +/* Marks the slot with the given slot number as active. Returns + * AVB_IO_RESULT_OK on success, error code otherwise. + * + * This function is typically used by the OS updater when completing + * an update. It can also used by the firmware for implementing the + * "set_active" command. + */ +AvbIOResult avb_ab_mark_slot_active(AvbABOps* ab_ops, unsigned int slot_number); + +/* Marks the slot with the given slot number as unbootable. Returns + * AVB_IO_RESULT_OK on success, error code otherwise. + * + * This function is typically used by the OS updater before writing to + * a slot. + */ +AvbIOResult avb_ab_mark_slot_unbootable(AvbABOps* ab_ops, + unsigned int slot_number); + +/* Marks the slot with the given slot number as having booted + * successfully. Returns AVB_IO_RESULT_OK on success, error code + * otherwise. + * + * Calling this on an unbootable slot is an error - AVB_IO_RESULT_OK + * will be returned yet the function will have no side-effects. + * + * This function is typically used by the OS updater after having + * confirmed that the slot works as intended. + */ +AvbIOResult avb_ab_mark_slot_successful(AvbABOps* ab_ops, + unsigned int slot_number); + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_AB_FLOW_H_ */ diff --git a/lib/avb/libavb_ab/avb_ab_ops.h b/lib/avb/libavb_ab/avb_ab_ops.h new file mode 100644 index 0000000..d3f6c01 --- /dev/null +++ b/lib/avb/libavb_ab/avb_ab_ops.h @@ -0,0 +1,78 @@ +/* + * Copyright (C) 2016 The Android Open Source Project + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#if !defined(AVB_INSIDE_LIBAVB_AB_H) && !defined(AVB_COMPILATION) +#error "Never include this file directly, include libavb/libavb_ab.h instead." +#endif + +#ifndef AVB_AB_OPS_H_ +#define AVB_AB_OPS_H_ + +#include "../libavb/libavb.h" + +#ifdef __cplusplus +extern "C" { +#endif + +struct AvbABOps; +typedef struct AvbABOps AvbABOps; + +struct AvbABData; + +/* High-level operations/functions/methods for A/B that are platform + * dependent. This struct extends the AvbOps struct from libavb. + */ +struct AvbABOps { + /* Operations from libavb. */ + AvbOps ops; + + /* Reads A/B metadata from persistent storage. Returned data is + * properly byteswapped. Returns AVB_IO_RESULT_OK on success, error + * code otherwise. + * + * If the data read is invalid (e.g. wrong magic or CRC checksum + * failure), the metadata shoule be reset using avb_ab_data_init() + * and then written to persistent storage. + * + * Implementations will typically want to use avb_ab_data_read() + * here to use the 'misc' partition for persistent storage. + */ + AvbIOResult (*read_ab_metadata)(AvbABOps* ab_ops, struct AvbABData* data); + + /* Writes A/B metadata to persistent storage. This will byteswap and + * update the CRC as needed. Returns AVB_IO_RESULT_OK on success, + * error code otherwise. + * + * Implementations will typically want to use avb_ab_data_write() + * here to use the 'misc' partition for persistent storage. + */ + AvbIOResult (*write_ab_metadata)(AvbABOps* ab_ops, + const struct AvbABData* data); +}; + +#ifdef __cplusplus +} +#endif + +#endif /* AVB_AB_OPS_H_ */ |