1 /* 2 * Copyright 2011 Calxeda, Inc. 3 * 4 * SPDX-License-Identifier: GPL-2.0+ 5 */ 6 7 #include <common.h> 8 #include <linux/ctype.h> 9 #include <errno.h> 10 #include <common.h> 11 #include <asm/io.h> 12 #include <part_efi.h> 13 #include <malloc.h> 14 15 /* 16 * UUID - Universally Unique IDentifier - 128 bits unique number. 17 * There are 5 versions and one variant of UUID defined by RFC4122 18 * specification. A UUID contains a set of fields. The set varies 19 * depending on the version of the UUID, as shown below: 20 * - time, MAC address(v1), 21 * - user ID(v2), 22 * - MD5 of name or URL(v3), 23 * - random data(v4), 24 * - SHA-1 of name or URL(v5), 25 * 26 * Layout of UUID: 27 * timestamp - 60-bit: time_low, time_mid, time_hi_and_version 28 * version - 4 bit (bit 4 through 7 of the time_hi_and_version) 29 * clock seq - 14 bit: clock_seq_hi_and_reserved, clock_seq_low 30 * variant: - bit 6 and 7 of clock_seq_hi_and_reserved 31 * node - 48 bit 32 * 33 * source: https://www.ietf.org/rfc/rfc4122.txt 34 * 35 * UUID binary format (16 bytes): 36 * 37 * 4B-2B-2B-2B-6B (big endian - network byte order) 38 * 39 * UUID string is 36 length of characters (36 bytes): 40 * 41 * 0 9 14 19 24 42 * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx 43 * be be be be be 44 * 45 * where x is a hexadecimal character. Fields are separated by '-'s. 46 * When converting to a binary UUID, le means the field should be converted 47 * to little endian and be means it should be converted to big endian. 48 * 49 * UUID is also used as GUID (Globally Unique Identifier) with the same binary 50 * format but it differs in string format like below. 51 * 52 * GUID: 53 * 0 9 14 19 24 54 * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx 55 * le le le be be 56 * 57 * GUID is used e.g. in GPT (GUID Partition Table) as a partiions unique id. 58 */ 59 int uuid_str_valid(const char *uuid) 60 { 61 int i, valid; 62 63 if (uuid == NULL) 64 return 0; 65 66 for (i = 0, valid = 1; uuid[i] && valid; i++) { 67 switch (i) { 68 case 8: case 13: case 18: case 23: 69 valid = (uuid[i] == '-'); 70 break; 71 default: 72 valid = isxdigit(uuid[i]); 73 break; 74 } 75 } 76 77 if (i != UUID_STR_LEN || !valid) 78 return 0; 79 80 return 1; 81 } 82 83 /* 84 * uuid_str_to_bin() - convert string UUID or GUID to big endian binary data. 85 * 86 * @param uuid_str - pointer to UUID or GUID string [37B] 87 * @param uuid_bin - pointer to allocated array for big endian output [16B] 88 * @str_format - UUID string format: 0 - UUID; 1 - GUID 89 */ 90 int uuid_str_to_bin(char *uuid_str, unsigned char *uuid_bin, int str_format) 91 { 92 uint16_t tmp16; 93 uint32_t tmp32; 94 uint64_t tmp64; 95 96 if (!uuid_str_valid(uuid_str)) 97 return -EINVAL; 98 99 if (str_format == UUID_STR_FORMAT_STD) { 100 tmp32 = cpu_to_be32(simple_strtoul(uuid_str, NULL, 16)); 101 memcpy(uuid_bin, &tmp32, 4); 102 103 tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 9, NULL, 16)); 104 memcpy(uuid_bin + 4, &tmp16, 2); 105 106 tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 14, NULL, 16)); 107 memcpy(uuid_bin + 6, &tmp16, 2); 108 } else { 109 tmp32 = cpu_to_le32(simple_strtoul(uuid_str, NULL, 16)); 110 memcpy(uuid_bin, &tmp32, 4); 111 112 tmp16 = cpu_to_le16(simple_strtoul(uuid_str + 9, NULL, 16)); 113 memcpy(uuid_bin + 4, &tmp16, 2); 114 115 tmp16 = cpu_to_le16(simple_strtoul(uuid_str + 14, NULL, 16)); 116 memcpy(uuid_bin + 6, &tmp16, 2); 117 } 118 119 tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 19, NULL, 16)); 120 memcpy(uuid_bin + 8, &tmp16, 2); 121 122 tmp64 = cpu_to_be64(simple_strtoull(uuid_str + 24, NULL, 16)); 123 memcpy(uuid_bin + 10, (char *)&tmp64 + 2, 6); 124 125 return 0; 126 } 127 128 /* 129 * uuid_bin_to_str() - convert big endian binary data to string UUID or GUID. 130 * 131 * @param uuid_bin - pointer to binary data of UUID (big endian) [16B] 132 * @param uuid_str - pointer to allocated array for output string [37B] 133 * @str_format - UUID string format: 0 - UUID; 1 - GUID 134 */ 135 void uuid_bin_to_str(unsigned char *uuid_bin, char *uuid_str, int str_format) 136 { 137 const u8 uuid_char_order[UUID_BIN_LEN] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 138 9, 10, 11, 12, 13, 14, 15}; 139 const u8 guid_char_order[UUID_BIN_LEN] = {3, 2, 1, 0, 5, 4, 7, 6, 8, 140 9, 10, 11, 12, 13, 14, 15}; 141 const u8 *char_order; 142 int i; 143 144 /* 145 * UUID and GUID bin data - always in big endian: 146 * 4B-2B-2B-2B-6B 147 * be be be be be 148 */ 149 if (str_format == UUID_STR_FORMAT_STD) 150 char_order = uuid_char_order; 151 else 152 char_order = guid_char_order; 153 154 for (i = 0; i < 16; i++) { 155 sprintf(uuid_str, "%02x", uuid_bin[char_order[i]]); 156 uuid_str += 2; 157 switch (i) { 158 case 3: 159 case 5: 160 case 7: 161 case 9: 162 *uuid_str++ = '-'; 163 break; 164 } 165 } 166 } 167 168 /* 169 * gen_rand_uuid() - this function generates a random binary UUID version 4. 170 * In this version all fields beside 4 bits of version and 171 * 2 bits of variant are randomly generated. 172 * 173 * @param uuid_bin - pointer to allocated array [16B]. Output is in big endian. 174 */ 175 #if defined(CONFIG_RANDOM_UUID) || defined(CONFIG_CMD_UUID) 176 void gen_rand_uuid(unsigned char *uuid_bin) 177 { 178 struct uuid uuid; 179 unsigned int *ptr = (unsigned int *)&uuid; 180 int i; 181 182 /* Set all fields randomly */ 183 for (i = 0; i < sizeof(struct uuid) / sizeof(*ptr); i++) 184 *(ptr + i) = cpu_to_be32(rand()); 185 186 clrsetbits_be16(&uuid.time_hi_and_version, 187 UUID_VERSION_MASK, 188 UUID_VERSION << UUID_VERSION_SHIFT); 189 190 clrsetbits_8(&uuid.clock_seq_hi_and_reserved, 191 UUID_VARIANT_MASK, 192 UUID_VARIANT << UUID_VARIANT_SHIFT); 193 194 memcpy(uuid_bin, &uuid, sizeof(struct uuid)); 195 } 196 197 /* 198 * gen_rand_uuid_str() - this function generates UUID v4 (random) in two string 199 * formats UUID or GUID. 200 * 201 * @param uuid_str - pointer to allocated array [37B]. 202 * @param - uuid output type: UUID - 0, GUID - 1 203 */ 204 void gen_rand_uuid_str(char *uuid_str, int str_format) 205 { 206 unsigned char uuid_bin[UUID_BIN_LEN]; 207 208 /* Generate UUID (big endian) */ 209 gen_rand_uuid(uuid_bin); 210 211 /* Convert UUID bin to UUID or GUID formated STRING */ 212 uuid_bin_to_str(uuid_bin, uuid_str, str_format); 213 } 214 215 #ifdef CONFIG_CMD_UUID 216 int do_uuid(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) 217 { 218 char uuid[UUID_STR_LEN + 1]; 219 int str_format; 220 221 if (!strcmp(argv[0], "uuid")) 222 str_format = UUID_STR_FORMAT_STD; 223 else 224 str_format = UUID_STR_FORMAT_GUID; 225 226 if (argc > 2) 227 return CMD_RET_USAGE; 228 229 gen_rand_uuid_str(uuid, str_format); 230 231 if (argc == 1) 232 printf("%s\n", uuid); 233 else 234 setenv(argv[1], uuid); 235 236 return CMD_RET_SUCCESS; 237 } 238 239 U_BOOT_CMD(uuid, CONFIG_SYS_MAXARGS, 1, do_uuid, 240 "UUID - generate random Universally Unique Identifier", 241 "[<varname>]\n" 242 "Argument:\n" 243 "varname: for set result in a environment variable\n" 244 "e.g. uuid uuid_env" 245 ); 246 247 U_BOOT_CMD(guid, CONFIG_SYS_MAXARGS, 1, do_uuid, 248 "GUID - generate Globally Unique Identifier based on random UUID", 249 "[<varname>]\n" 250 "Argument:\n" 251 "varname: for set result in a environment variable\n" 252 "e.g. guid guid_env" 253 ); 254 #endif /* CONFIG_CMD_UUID */ 255 #endif /* CONFIG_RANDOM_UUID || CONFIG_CMD_UUID */ 256