summaryrefslogtreecommitdiff
path: root/lib/tpm.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/tpm.c')
-rw-r--r--lib/tpm.c581
1 files changed, 581 insertions, 0 deletions
diff --git a/lib/tpm.c b/lib/tpm.c
new file mode 100644
index 0000000..42c9bea
--- /dev/null
+++ b/lib/tpm.c
@@ -0,0 +1,581 @@
+/*
+ * Copyright (c) 2013 The Chromium OS Authors.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <stdarg.h>
+#include <tpm.h>
+#include <asm/unaligned.h>
+
+/* Internal error of TPM command library */
+#define TPM_LIB_ERROR ((uint32_t)~0u)
+
+/* Useful constants */
+enum {
+ COMMAND_BUFFER_SIZE = 256,
+ TPM_PUBEK_SIZE = 256,
+ TPM_REQUEST_HEADER_LENGTH = 10,
+ TPM_RESPONSE_HEADER_LENGTH = 10,
+ PCR_DIGEST_LENGTH = 20,
+};
+
+/**
+ * Pack data into a byte string. The data types are specified in
+ * the format string: 'b' means unsigned byte, 'w' unsigned word,
+ * 'd' unsigned double word, and 's' byte string. The data are a
+ * series of offsets and values (for type byte string there are also
+ * lengths). The data values are packed into the byte string
+ * sequentially, and so a latter value could over-write a former
+ * value.
+ *
+ * @param str output string
+ * @param size size of output string
+ * @param format format string
+ * @param ... data points
+ * @return 0 on success, non-0 on error
+ */
+int pack_byte_string(uint8_t *str, size_t size, const char *format, ...)
+{
+ va_list args;
+ size_t offset = 0, length = 0;
+ uint8_t *data = NULL;
+ uint32_t value = 0;
+
+ va_start(args, format);
+ for (; *format; format++) {
+ switch (*format) {
+ case 'b':
+ offset = va_arg(args, size_t);
+ value = va_arg(args, int);
+ length = 1;
+ break;
+ case 'w':
+ offset = va_arg(args, size_t);
+ value = va_arg(args, int);
+ length = 2;
+ break;
+ case 'd':
+ offset = va_arg(args, size_t);
+ value = va_arg(args, uint32_t);
+ length = 4;
+ break;
+ case 's':
+ offset = va_arg(args, size_t);
+ data = va_arg(args, uint8_t *);
+ length = va_arg(args, uint32_t);
+ break;
+ default:
+ debug("Couldn't recognize format string\n");
+ return -1;
+ }
+
+ if (offset + length > size)
+ return -1;
+
+ switch (*format) {
+ case 'b':
+ str[offset] = value;
+ break;
+ case 'w':
+ put_unaligned_be16(value, str + offset);
+ break;
+ case 'd':
+ put_unaligned_be32(value, str + offset);
+ break;
+ case 's':
+ memcpy(str + offset, data, length);
+ break;
+ }
+ }
+ va_end(args);
+
+ return 0;
+}
+
+/**
+ * Unpack data from a byte string. The data types are specified in
+ * the format string: 'b' means unsigned byte, 'w' unsigned word,
+ * 'd' unsigned double word, and 's' byte string. The data are a
+ * series of offsets and pointers (for type byte string there are also
+ * lengths).
+ *
+ * @param str output string
+ * @param size size of output string
+ * @param format format string
+ * @param ... data points
+ * @return 0 on success, non-0 on error
+ */
+int unpack_byte_string(const uint8_t *str, size_t size, const char *format, ...)
+{
+ va_list args;
+ size_t offset = 0, length = 0;
+ uint8_t *ptr8 = NULL;
+ uint16_t *ptr16 = NULL;
+ uint32_t *ptr32 = NULL;
+
+ va_start(args, format);
+ for (; *format; format++) {
+ switch (*format) {
+ case 'b':
+ offset = va_arg(args, size_t);
+ ptr8 = va_arg(args, uint8_t *);
+ length = 1;
+ break;
+ case 'w':
+ offset = va_arg(args, size_t);
+ ptr16 = va_arg(args, uint16_t *);
+ length = 2;
+ break;
+ case 'd':
+ offset = va_arg(args, size_t);
+ ptr32 = va_arg(args, uint32_t *);
+ length = 4;
+ break;
+ case 's':
+ offset = va_arg(args, size_t);
+ ptr8 = va_arg(args, uint8_t *);
+ length = va_arg(args, uint32_t);
+ break;
+ default:
+ debug("Couldn't recognize format string\n");
+ return -1;
+ }
+
+ if (offset + length > size)
+ return -1;
+
+ switch (*format) {
+ case 'b':
+ *ptr8 = str[offset];
+ break;
+ case 'w':
+ *ptr16 = get_unaligned_be16(str + offset);
+ break;
+ case 'd':
+ *ptr32 = get_unaligned_be32(str + offset);
+ break;
+ case 's':
+ memcpy(ptr8, str + offset, length);
+ break;
+ }
+ }
+ va_end(args);
+
+ return 0;
+}
+
+/**
+ * Get TPM command size.
+ *
+ * @param command byte string of TPM command
+ * @return command size of the TPM command
+ */
+static uint32_t tpm_command_size(const void *command)
+{
+ const size_t command_size_offset = 2;
+ return get_unaligned_be32(command + command_size_offset);
+}
+
+/**
+ * Get TPM response return code, which is one of TPM_RESULT values.
+ *
+ * @param response byte string of TPM response
+ * @return return code of the TPM response
+ */
+static uint32_t tpm_return_code(const void *response)
+{
+ const size_t return_code_offset = 6;
+ return get_unaligned_be32(response + return_code_offset);
+}
+
+/**
+ * Send a TPM command and return response's return code, and optionally
+ * return response to caller.
+ *
+ * @param command byte string of TPM command
+ * @param response output buffer for TPM response, or NULL if the
+ * caller does not care about it
+ * @param size_ptr output buffer size (input parameter) and TPM
+ * response length (output parameter); this parameter
+ * is a bidirectional
+ * @return return code of the TPM response
+ */
+static uint32_t tpm_sendrecv_command(const void *command,
+ void *response, size_t *size_ptr)
+{
+ uint8_t response_buffer[COMMAND_BUFFER_SIZE];
+ size_t response_length;
+ uint32_t err;
+
+ if (response) {
+ response_length = *size_ptr;
+ } else {
+ response = response_buffer;
+ response_length = sizeof(response_buffer);
+ }
+ err = tis_sendrecv(command, tpm_command_size(command),
+ response, &response_length);
+ if (err)
+ return TPM_LIB_ERROR;
+ if (response)
+ *size_ptr = response_length;
+
+ return tpm_return_code(response);
+}
+
+uint32_t tpm_init(void)
+{
+ uint32_t err;
+
+ err = tis_init();
+ if (err)
+ return err;
+
+ return tis_open();
+}
+
+uint32_t tpm_startup(enum tpm_startup_type mode)
+{
+ const uint8_t command[12] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0xc, 0x0, 0x0, 0x0, 0x99, 0x0, 0x0,
+ };
+ const size_t mode_offset = 10;
+ uint8_t buf[COMMAND_BUFFER_SIZE];
+
+ if (pack_byte_string(buf, sizeof(buf), "sw",
+ 0, command, sizeof(command),
+ mode_offset, mode))
+ return TPM_LIB_ERROR;
+
+ return tpm_sendrecv_command(buf, NULL, NULL);
+}
+
+uint32_t tpm_self_test_full(void)
+{
+ const uint8_t command[10] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0xa, 0x0, 0x0, 0x0, 0x50,
+ };
+ return tpm_sendrecv_command(command, NULL, NULL);
+}
+
+uint32_t tpm_continue_self_test(void)
+{
+ const uint8_t command[10] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0xa, 0x0, 0x0, 0x0, 0x53,
+ };
+ return tpm_sendrecv_command(command, NULL, NULL);
+}
+
+uint32_t tpm_nv_define_space(uint32_t index, uint32_t perm, uint32_t size)
+{
+ const uint8_t command[101] = {
+ 0x0, 0xc1, /* TPM_TAG */
+ 0x0, 0x0, 0x0, 0x65, /* parameter size */
+ 0x0, 0x0, 0x0, 0xcc, /* TPM_COMMAND_CODE */
+ /* TPM_NV_DATA_PUBLIC->... */
+ 0x0, 0x18, /* ...->TPM_STRUCTURE_TAG */
+ 0, 0, 0, 0, /* ...->TPM_NV_INDEX */
+ /* TPM_NV_DATA_PUBLIC->TPM_PCR_INFO_SHORT */
+ 0x0, 0x3,
+ 0, 0, 0,
+ 0x1f,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ /* TPM_NV_DATA_PUBLIC->TPM_PCR_INFO_SHORT */
+ 0x0, 0x3,
+ 0, 0, 0,
+ 0x1f,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ /* TPM_NV_ATTRIBUTES->... */
+ 0x0, 0x17, /* ...->TPM_STRUCTURE_TAG */
+ 0, 0, 0, 0, /* ...->attributes */
+ /* End of TPM_NV_ATTRIBUTES */
+ 0, /* bReadSTClear */
+ 0, /* bWriteSTClear */
+ 0, /* bWriteDefine */
+ 0, 0, 0, 0, /* size */
+ };
+ const size_t index_offset = 12;
+ const size_t perm_offset = 70;
+ const size_t size_offset = 77;
+ uint8_t buf[COMMAND_BUFFER_SIZE];
+
+ if (pack_byte_string(buf, sizeof(buf), "sddd",
+ 0, command, sizeof(command),
+ index_offset, index,
+ perm_offset, perm,
+ size_offset, size))
+ return TPM_LIB_ERROR;
+
+ return tpm_sendrecv_command(buf, NULL, NULL);
+}
+
+uint32_t tpm_nv_read_value(uint32_t index, void *data, uint32_t count)
+{
+ const uint8_t command[22] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0x16, 0x0, 0x0, 0x0, 0xcf,
+ };
+ const size_t index_offset = 10;
+ const size_t length_offset = 18;
+ const size_t data_size_offset = 10;
+ const size_t data_offset = 14;
+ uint8_t buf[COMMAND_BUFFER_SIZE], response[COMMAND_BUFFER_SIZE];
+ size_t response_length = sizeof(response);
+ uint32_t data_size;
+ uint32_t err;
+
+ if (pack_byte_string(buf, sizeof(buf), "sdd",
+ 0, command, sizeof(command),
+ index_offset, index,
+ length_offset, count))
+ return TPM_LIB_ERROR;
+ err = tpm_sendrecv_command(buf, response, &response_length);
+ if (err)
+ return err;
+ if (unpack_byte_string(response, response_length, "d",
+ data_size_offset, &data_size))
+ return TPM_LIB_ERROR;
+ if (data_size > count)
+ return TPM_LIB_ERROR;
+ if (unpack_byte_string(response, response_length, "s",
+ data_offset, data, data_size))
+ return TPM_LIB_ERROR;
+
+ return 0;
+}
+
+uint32_t tpm_nv_write_value(uint32_t index, const void *data, uint32_t length)
+{
+ const uint8_t command[256] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xcd,
+ };
+ const size_t command_size_offset = 2;
+ const size_t index_offset = 10;
+ const size_t length_offset = 18;
+ const size_t data_offset = 22;
+ const size_t write_info_size = 12;
+ const uint32_t total_length =
+ TPM_REQUEST_HEADER_LENGTH + write_info_size + length;
+ uint8_t buf[COMMAND_BUFFER_SIZE], response[COMMAND_BUFFER_SIZE];
+ size_t response_length = sizeof(response);
+ uint32_t err;
+
+ if (pack_byte_string(buf, sizeof(buf), "sddds",
+ 0, command, sizeof(command),
+ command_size_offset, total_length,
+ index_offset, index,
+ length_offset, length,
+ data_offset, data, length))
+ return TPM_LIB_ERROR;
+ err = tpm_sendrecv_command(buf, response, &response_length);
+ if (err)
+ return err;
+
+ return 0;
+}
+
+uint32_t tpm_extend(uint32_t index, const void *in_digest, void *out_digest)
+{
+ const uint8_t command[34] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0x22, 0x0, 0x0, 0x0, 0x14,
+ };
+ const size_t index_offset = 10;
+ const size_t in_digest_offset = 14;
+ const size_t out_digest_offset = 10;
+ uint8_t buf[COMMAND_BUFFER_SIZE];
+ uint8_t response[TPM_RESPONSE_HEADER_LENGTH + PCR_DIGEST_LENGTH];
+ size_t response_length = sizeof(response);
+ uint32_t err;
+
+ if (pack_byte_string(buf, sizeof(buf), "sds",
+ 0, command, sizeof(command),
+ index_offset, index,
+ in_digest_offset, in_digest,
+ PCR_DIGEST_LENGTH))
+ return TPM_LIB_ERROR;
+ err = tpm_sendrecv_command(buf, response, &response_length);
+ if (err)
+ return err;
+
+ if (unpack_byte_string(response, response_length, "s",
+ out_digest_offset, out_digest,
+ PCR_DIGEST_LENGTH))
+ return TPM_LIB_ERROR;
+
+ return 0;
+}
+
+uint32_t tpm_pcr_read(uint32_t index, void *data, size_t count)
+{
+ const uint8_t command[14] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0xe, 0x0, 0x0, 0x0, 0x15,
+ };
+ const size_t index_offset = 10;
+ const size_t out_digest_offset = 10;
+ uint8_t buf[COMMAND_BUFFER_SIZE], response[COMMAND_BUFFER_SIZE];
+ size_t response_length = sizeof(response);
+ uint32_t err;
+
+ if (count < PCR_DIGEST_LENGTH)
+ return TPM_LIB_ERROR;
+
+ if (pack_byte_string(buf, sizeof(buf), "sd",
+ 0, command, sizeof(command),
+ index_offset, index))
+ return TPM_LIB_ERROR;
+ err = tpm_sendrecv_command(buf, response, &response_length);
+ if (err)
+ return err;
+ if (unpack_byte_string(response, response_length, "s",
+ out_digest_offset, data, PCR_DIGEST_LENGTH))
+ return TPM_LIB_ERROR;
+
+ return 0;
+}
+
+uint32_t tpm_tsc_physical_presence(uint16_t presence)
+{
+ const uint8_t command[12] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0xc, 0x40, 0x0, 0x0, 0xa, 0x0, 0x0,
+ };
+ const size_t presence_offset = 10;
+ uint8_t buf[COMMAND_BUFFER_SIZE];
+
+ if (pack_byte_string(buf, sizeof(buf), "sw",
+ 0, command, sizeof(command),
+ presence_offset, presence))
+ return TPM_LIB_ERROR;
+
+ return tpm_sendrecv_command(buf, NULL, NULL);
+}
+
+uint32_t tpm_read_pubek(void *data, size_t count)
+{
+ const uint8_t command[30] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0x1e, 0x0, 0x0, 0x0, 0x7c,
+ };
+ const size_t response_size_offset = 2;
+ const size_t data_offset = 10;
+ const size_t header_and_checksum_size = TPM_RESPONSE_HEADER_LENGTH + 20;
+ uint8_t response[COMMAND_BUFFER_SIZE + TPM_PUBEK_SIZE];
+ size_t response_length = sizeof(response);
+ uint32_t data_size;
+ uint32_t err;
+
+ err = tpm_sendrecv_command(command, response, &response_length);
+ if (err)
+ return err;
+ if (unpack_byte_string(response, response_length, "d",
+ response_size_offset, &data_size))
+ return TPM_LIB_ERROR;
+ if (data_size < header_and_checksum_size)
+ return TPM_LIB_ERROR;
+ data_size -= header_and_checksum_size;
+ if (data_size > count)
+ return TPM_LIB_ERROR;
+ if (unpack_byte_string(response, response_length, "s",
+ data_offset, data, data_size))
+ return TPM_LIB_ERROR;
+
+ return 0;
+}
+
+uint32_t tpm_force_clear(void)
+{
+ const uint8_t command[10] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0xa, 0x0, 0x0, 0x0, 0x5d,
+ };
+
+ return tpm_sendrecv_command(command, NULL, NULL);
+}
+
+uint32_t tpm_physical_enable(void)
+{
+ const uint8_t command[10] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0xa, 0x0, 0x0, 0x0, 0x6f,
+ };
+
+ return tpm_sendrecv_command(command, NULL, NULL);
+}
+
+uint32_t tpm_physical_disable(void)
+{
+ const uint8_t command[10] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0xa, 0x0, 0x0, 0x0, 0x70,
+ };
+
+ return tpm_sendrecv_command(command, NULL, NULL);
+}
+
+uint32_t tpm_physical_set_deactivated(uint8_t state)
+{
+ const uint8_t command[11] = {
+ 0x0, 0xc1, 0x0, 0x0, 0x0, 0xb, 0x0, 0x0, 0x0, 0x72,
+ };
+ const size_t state_offset = 10;
+ uint8_t buf[COMMAND_BUFFER_SIZE];
+
+ if (pack_byte_string(buf, sizeof(buf), "sb",
+ 0, command, sizeof(command),
+ state_offset, state))
+ return TPM_LIB_ERROR;
+
+ return tpm_sendrecv_command(buf, NULL, NULL);
+}
+
+uint32_t tpm_get_capability(uint32_t cap_area, uint32_t sub_cap,
+ void *cap, size_t count)
+{
+ const uint8_t command[22] = {
+ 0x0, 0xc1, /* TPM_TAG */
+ 0x0, 0x0, 0x0, 0x16, /* parameter size */
+ 0x0, 0x0, 0x0, 0x65, /* TPM_COMMAND_CODE */
+ 0x0, 0x0, 0x0, 0x0, /* TPM_CAPABILITY_AREA */
+ 0x0, 0x0, 0x0, 0x4, /* subcap size */
+ 0x0, 0x0, 0x0, 0x0, /* subcap value */
+ };
+ const size_t cap_area_offset = 10;
+ const size_t sub_cap_offset = 18;
+ const size_t cap_offset = 14;
+ const size_t cap_size_offset = 10;
+ uint8_t buf[COMMAND_BUFFER_SIZE], response[COMMAND_BUFFER_SIZE];
+ size_t response_length = sizeof(response);
+ uint32_t cap_size;
+ uint32_t err;
+
+ if (pack_byte_string(buf, sizeof(buf), "sdd",
+ 0, command, sizeof(command),
+ cap_area_offset, cap_area,
+ sub_cap_offset, sub_cap))
+ return TPM_LIB_ERROR;
+ err = tpm_sendrecv_command(buf, response, &response_length);
+ if (err)
+ return err;
+ if (unpack_byte_string(response, response_length, "d",
+ cap_size_offset, &cap_size))
+ return TPM_LIB_ERROR;
+ if (cap_size > response_length || cap_size > count)
+ return TPM_LIB_ERROR;
+ if (unpack_byte_string(response, response_length, "s",
+ cap_offset, cap, cap_size))
+ return TPM_LIB_ERROR;
+
+ return 0;
+}
generated by cgit v1.1 at 2024-11-25 04:17:31 +0000