2 * Copyright 2011 Calxeda, Inc.
4 * SPDX-License-Identifier: GPL-2.0+
7 #include <linux/ctype.h>
15 * UUID - Universally Unique IDentifier - 128 bits unique number.
16 * There are 5 versions and one variant of UUID defined by RFC4122
17 * specification. Depends on version uuid number base on a time,
18 * host name, MAC address or random data.
20 * UUID binary format (16 bytes):
22 * 4B-2B-2B-2B-6B (big endian - network byte order)
24 * UUID string is 36 length of characters (36 bytes):
27 * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
30 * where x is a hexadecimal character. Fields are separated by '-'s.
31 * When converting to a binary UUID, le means the field should be converted
32 * to little endian and be means it should be converted to big endian.
34 * UUID is also used as GUID (Globally Unique Identifier) with the same binary
35 * format but it differs in string format like below.
39 * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
42 * GUID is used e.g. in GPT (GUID Partition Table) as a partiions unique id.
44 int uuid_str_valid(const char *uuid)
51 for (i = 0, valid = 1; uuid[i] && valid; i++) {
53 case 8: case 13: case 18: case 23:
54 valid = (uuid[i] == '-');
57 valid = isxdigit(uuid[i]);
62 if (i != UUID_STR_LEN || !valid)
69 * uuid_str_to_bin() - convert string UUID or GUID to big endian binary data.
71 * @param uuid_str - pointer to UUID or GUID string [37B]
72 * @param uuid_bin - pointer to allocated array for big endian output [16B]
73 * @str_format - UUID string format: 0 - UUID; 1 - GUID
75 int uuid_str_to_bin(char *uuid_str, unsigned char *uuid_bin, int str_format)
81 if (!uuid_str_valid(uuid_str))
84 if (str_format == UUID_STR_FORMAT_STD) {
85 tmp32 = cpu_to_be32(simple_strtoul(uuid_str, NULL, 16));
86 memcpy(uuid_bin, &tmp32, 4);
88 tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 9, NULL, 16));
89 memcpy(uuid_bin + 4, &tmp16, 2);
91 tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 14, NULL, 16));
92 memcpy(uuid_bin + 6, &tmp16, 2);
94 tmp32 = cpu_to_le32(simple_strtoul(uuid_str, NULL, 16));
95 memcpy(uuid_bin, &tmp32, 4);
97 tmp16 = cpu_to_le16(simple_strtoul(uuid_str + 9, NULL, 16));
98 memcpy(uuid_bin + 4, &tmp16, 2);
100 tmp16 = cpu_to_le16(simple_strtoul(uuid_str + 14, NULL, 16));
101 memcpy(uuid_bin + 6, &tmp16, 2);
104 tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 19, NULL, 16));
105 memcpy(uuid_bin + 8, &tmp16, 2);
107 tmp64 = cpu_to_be64(simple_strtoull(uuid_str + 24, NULL, 16));
108 memcpy(uuid_bin + 10, (char *)&tmp64 + 2, 6);
114 * uuid_bin_to_str() - convert big endian binary data to string UUID or GUID.
116 * @param uuid_bin - pointer to binary data of UUID (big endian) [16B]
117 * @param uuid_str - pointer to allocated array for output string [37B]
118 * @str_format - UUID string format: 0 - UUID; 1 - GUID
120 void uuid_bin_to_str(unsigned char *uuid_bin, char *uuid_str, int str_format)
122 const u8 uuid_char_order[UUID_BIN_LEN] = {0, 1, 2, 3, 4, 5, 6, 7, 8,
123 9, 10, 11, 12, 13, 14, 15};
124 const u8 guid_char_order[UUID_BIN_LEN] = {3, 2, 1, 0, 5, 4, 7, 6, 8,
125 9, 10, 11, 12, 13, 14, 15};
126 const u8 *char_order;
130 * UUID and GUID bin data - always in big endian:
134 if (str_format == UUID_STR_FORMAT_STD)
135 char_order = uuid_char_order;
137 char_order = guid_char_order;
139 for (i = 0; i < 16; i++) {
140 sprintf(uuid_str, "%02x", uuid_bin[char_order[i]]);