diff options
Diffstat (limited to 'lib/uuid.c')
| -rw-r--r-- | lib/uuid.c | 226 |
1 files changed, 206 insertions, 20 deletions
@@ -4,21 +4,58 @@ * SPDX-License-Identifier: GPL-2.0+ */ +#include <common.h> #include <linux/ctype.h> -#include "common.h" +#include <errno.h> +#include <common.h> +#include <asm/io.h> +#include <part_efi.h> +#include <malloc.h> /* - * This is what a UUID string looks like. + * UUID - Universally Unique IDentifier - 128 bits unique number. + * There are 5 versions and one variant of UUID defined by RFC4122 + * specification. A UUID contains a set of fields. The set varies + * depending on the version of the UUID, as shown below: + * - time, MAC address(v1), + * - user ID(v2), + * - MD5 of name or URL(v3), + * - random data(v4), + * - SHA-1 of name or URL(v5), * - * x is a hexadecimal character. fields are separated by '-'s. When converting - * to a binary UUID, le means the field should be converted to little endian, - * and be means it should be converted to big endian. + * Layout of UUID: + * timestamp - 60-bit: time_low, time_mid, time_hi_and_version + * version - 4 bit (bit 4 through 7 of the time_hi_and_version) + * clock seq - 14 bit: clock_seq_hi_and_reserved, clock_seq_low + * variant: - bit 6 and 7 of clock_seq_hi_and_reserved + * node - 48 bit + * + * source: https://www.ietf.org/rfc/rfc4122.txt + * + * UUID binary format (16 bytes): + * + * 4B-2B-2B-2B-6B (big endian - network byte order) + * + * UUID string is 36 length of characters (36 bytes): * * 0 9 14 19 24 * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx + * be be be be be + * + * where x is a hexadecimal character. Fields are separated by '-'s. + * When converting to a binary UUID, le means the field should be converted + * to little endian and be means it should be converted to big endian. + * + * UUID is also used as GUID (Globally Unique Identifier) with the same binary + * format but it differs in string format like below. + * + * GUID: + * 0 9 14 19 24 + * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx * le le le be be + * + * GUID is used e.g. in GPT (GUID Partition Table) as a partiions unique id. */ - int uuid_str_valid(const char *uuid) { int i, valid; @@ -37,33 +74,182 @@ int uuid_str_valid(const char *uuid) } } - if (i != 36 || !valid) + if (i != UUID_STR_LEN || !valid) return 0; return 1; } -void uuid_str_to_bin(const char *uuid, unsigned char *out) +/* + * uuid_str_to_bin() - convert string UUID or GUID to big endian binary data. + * + * @param uuid_str - pointer to UUID or GUID string [37B] + * @param uuid_bin - pointer to allocated array for big endian output [16B] + * @str_format - UUID string format: 0 - UUID; 1 - GUID + */ +int uuid_str_to_bin(char *uuid_str, unsigned char *uuid_bin, int str_format) { uint16_t tmp16; uint32_t tmp32; uint64_t tmp64; - if (!uuid || !out) - return; + if (!uuid_str_valid(uuid_str)) + return -EINVAL; - tmp32 = cpu_to_le32(simple_strtoul(uuid, NULL, 16)); - memcpy(out, &tmp32, 4); + if (str_format == UUID_STR_FORMAT_STD) { + tmp32 = cpu_to_be32(simple_strtoul(uuid_str, NULL, 16)); + memcpy(uuid_bin, &tmp32, 4); - tmp16 = cpu_to_le16(simple_strtoul(uuid + 9, NULL, 16)); - memcpy(out + 4, &tmp16, 2); + tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 9, NULL, 16)); + memcpy(uuid_bin + 4, &tmp16, 2); - tmp16 = cpu_to_le16(simple_strtoul(uuid + 14, NULL, 16)); - memcpy(out + 6, &tmp16, 2); + tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 14, NULL, 16)); + memcpy(uuid_bin + 6, &tmp16, 2); + } else { + tmp32 = cpu_to_le32(simple_strtoul(uuid_str, NULL, 16)); + memcpy(uuid_bin, &tmp32, 4); - tmp16 = cpu_to_be16(simple_strtoul(uuid + 19, NULL, 16)); - memcpy(out + 8, &tmp16, 2); + tmp16 = cpu_to_le16(simple_strtoul(uuid_str + 9, NULL, 16)); + memcpy(uuid_bin + 4, &tmp16, 2); - tmp64 = cpu_to_be64(simple_strtoull(uuid + 24, NULL, 16)); - memcpy(out + 10, (char *)&tmp64 + 2, 6); + tmp16 = cpu_to_le16(simple_strtoul(uuid_str + 14, NULL, 16)); + memcpy(uuid_bin + 6, &tmp16, 2); + } + + tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 19, NULL, 16)); + memcpy(uuid_bin + 8, &tmp16, 2); + + tmp64 = cpu_to_be64(simple_strtoull(uuid_str + 24, NULL, 16)); + memcpy(uuid_bin + 10, (char *)&tmp64 + 2, 6); + + return 0; } + +/* + * uuid_bin_to_str() - convert big endian binary data to string UUID or GUID. + * + * @param uuid_bin - pointer to binary data of UUID (big endian) [16B] + * @param uuid_str - pointer to allocated array for output string [37B] + * @str_format - UUID string format: 0 - UUID; 1 - GUID + */ +void uuid_bin_to_str(unsigned char *uuid_bin, char *uuid_str, int str_format) +{ + const u8 uuid_char_order[UUID_BIN_LEN] = {0, 1, 2, 3, 4, 5, 6, 7, 8, + 9, 10, 11, 12, 13, 14, 15}; + const u8 guid_char_order[UUID_BIN_LEN] = {3, 2, 1, 0, 5, 4, 7, 6, 8, + 9, 10, 11, 12, 13, 14, 15}; + const u8 *char_order; + int i; + + /* + * UUID and GUID bin data - always in big endian: + * 4B-2B-2B-2B-6B + * be be be be be + */ + if (str_format == UUID_STR_FORMAT_STD) + char_order = uuid_char_order; + else + char_order = guid_char_order; + + for (i = 0; i < 16; i++) { + sprintf(uuid_str, "%02x", uuid_bin[char_order[i]]); + uuid_str += 2; + switch (i) { + case 3: + case 5: + case 7: + case 9: + *uuid_str++ = '-'; + break; + } + } +} + +/* + * gen_rand_uuid() - this function generates a random binary UUID version 4. + * In this version all fields beside 4 bits of version and + * 2 bits of variant are randomly generated. + * + * @param uuid_bin - pointer to allocated array [16B]. Output is in big endian. +*/ +#if defined(CONFIG_RANDOM_UUID) || defined(CONFIG_CMD_UUID) +void gen_rand_uuid(unsigned char *uuid_bin) +{ + struct uuid uuid; + unsigned int *ptr = (unsigned int *)&uuid; + int i; + + /* Set all fields randomly */ + for (i = 0; i < sizeof(struct uuid) / sizeof(*ptr); i++) + *(ptr + i) = cpu_to_be32(rand()); + + clrsetbits_be16(&uuid.time_hi_and_version, + UUID_VERSION_MASK, + UUID_VERSION << UUID_VERSION_SHIFT); + + clrsetbits_8(&uuid.clock_seq_hi_and_reserved, + UUID_VARIANT_MASK, + UUID_VARIANT << UUID_VARIANT_SHIFT); + + memcpy(uuid_bin, &uuid, sizeof(struct uuid)); +} + +/* + * gen_rand_uuid_str() - this function generates UUID v4 (random) in two string + * formats UUID or GUID. + * + * @param uuid_str - pointer to allocated array [37B]. + * @param - uuid output type: UUID - 0, GUID - 1 + */ +void gen_rand_uuid_str(char *uuid_str, int str_format) +{ + unsigned char uuid_bin[UUID_BIN_LEN]; + + /* Generate UUID (big endian) */ + gen_rand_uuid(uuid_bin); + + /* Convert UUID bin to UUID or GUID formated STRING */ + uuid_bin_to_str(uuid_bin, uuid_str, str_format); +} + +#ifdef CONFIG_CMD_UUID +int do_uuid(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) +{ + char uuid[UUID_STR_LEN + 1]; + int str_format; + + if (!strcmp(argv[0], "uuid")) + str_format = UUID_STR_FORMAT_STD; + else + str_format = UUID_STR_FORMAT_GUID; + + if (argc > 2) + return CMD_RET_USAGE; + + gen_rand_uuid_str(uuid, str_format); + + if (argc == 1) + printf("%s\n", uuid); + else + setenv(argv[1], uuid); + + return CMD_RET_SUCCESS; +} + +U_BOOT_CMD(uuid, CONFIG_SYS_MAXARGS, 1, do_uuid, + "UUID - generate random Universally Unique Identifier", + "[<varname>]\n" + "Argument:\n" + "varname: for set result in a environment variable\n" + "e.g. uuid uuid_env" +); + +U_BOOT_CMD(guid, CONFIG_SYS_MAXARGS, 1, do_uuid, + "GUID - generate Globally Unique Identifier based on random UUID", + "[<varname>]\n" + "Argument:\n" + "varname: for set result in a environment variable\n" + "e.g. guid guid_env" +); +#endif /* CONFIG_CMD_UUID */ +#endif /* CONFIG_RANDOM_UUID || CONFIG_CMD_UUID */ |