diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Makefile | 1 | ||||
| -rw-r--r-- | lib/uuid.c | 61 |
2 files changed, 55 insertions, 7 deletions
diff --git a/lib/Makefile b/lib/Makefile index ae80865..d7ff7ca 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -61,6 +61,7 @@ obj-y += string.o obj-y += time.o obj-$(CONFIG_TRACE) += trace.o obj-$(CONFIG_BOOTP_PXE) += uuid.o +obj-$(CONFIG_PARTITION_UUIDS) += uuid.o obj-y += vsprintf.o obj-$(CONFIG_LIB_RAND) += rand.o @@ -5,18 +5,40 @@ */ #include <linux/ctype.h> -#include "common.h" +#include <errno.h> +#include <common.h> + +#define UUID_STR_LEN 36 /* - * 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. Depends on version uuid number base on a time, + * host name, MAC address or random data. + * + * 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. * - * 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) @@ -43,14 +65,17 @@ int uuid_str_valid(const char *uuid) return 1; } -void uuid_str_to_bin(const char *uuid, unsigned char *out) +int uuid_str_to_bin(char *uuid, unsigned char *out) { uint16_t tmp16; uint32_t tmp32; uint64_t tmp64; if (!uuid || !out) - return; + return -EINVAL; + + if (strlen(uuid) != UUID_STR_LEN) + return -EINVAL; tmp32 = cpu_to_le32(simple_strtoul(uuid, NULL, 16)); memcpy(out, &tmp32, 4); @@ -66,4 +91,26 @@ void uuid_str_to_bin(const char *uuid, unsigned char *out) tmp64 = cpu_to_be64(simple_strtoull(uuid + 24, NULL, 16)); memcpy(out + 10, (char *)&tmp64 + 2, 6); + + return 0; +} + +void uuid_bin_to_str(unsigned char *uuid, char *str) +{ + static const u8 le[16] = {3, 2, 1, 0, 5, 4, 7, 6, 8, 9, 10, 11, + 12, 13, 14, 15}; + int i; + + for (i = 0; i < 16; i++) { + sprintf(str, "%02x", uuid[le[i]]); + str += 2; + switch (i) { + case 3: + case 5: + case 7: + case 9: + *str++ = '-'; + break; + } + } } |