1 /* $NetBSD: gpt_uuid.c,v 1.24 2024/12/18 20:56:40 andvar Exp $ */ 2 3 /*- 4 * Copyright (c) 2014 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #if HAVE_NBTOOL_CONFIG_H 30 #include "nbtool_config.h" 31 #endif 32 33 #include <sys/cdefs.h> 34 #ifdef __RCSID 35 __RCSID("$NetBSD: gpt_uuid.c,v 1.24 2024/12/18 20:56:40 andvar Exp $"); 36 #endif 37 38 #include <err.h> 39 #include <fcntl.h> 40 #include <stdio.h> 41 #include <unistd.h> 42 43 #include "map.h" 44 #include "gpt.h" 45 #include "gpt_private.h" 46 47 #if defined(HAVE_SYS_ENDIAN_H) || ! defined(HAVE_NBTOOL_CONFIG_H) 48 #include <sys/endian.h> 49 #endif 50 51 52 const gpt_uuid_t gpt_uuid_nil; 53 54 struct dce_uuid { 55 uint32_t time_low; 56 uint16_t time_mid; 57 uint16_t time_hi_and_version; 58 uint8_t clock_seq_hi_and_reserved; 59 uint8_t clock_seq_low; 60 uint8_t node[6]; 61 }; 62 63 static const struct { 64 struct dce_uuid u; 65 const char *n; 66 const char *d; 67 } gpt_nv[] = { 68 /* Must match the gpt_type_t enum in gpt_uuid.h */ 69 { GPT_ENT_TYPE_APPLE_HFS, "apple", "Apple HFS" }, 70 { GPT_ENT_TYPE_APPLE_UFS, "apple-ufs", "Apple UFS" }, 71 { GPT_ENT_TYPE_BIOS, "bios", "BIOS Boot" }, 72 { GPT_ENT_TYPE_EFI, "efi", "EFI System" }, 73 { GPT_ENT_TYPE_FREEBSD, "fbsd-legacy", "FreeBSD legacy" }, 74 { GPT_ENT_TYPE_FREEBSD_SWAP, "fbsd-swap", "FreeBSD swap" }, 75 { GPT_ENT_TYPE_FREEBSD_UFS, "fbsd-ufs", "FreeBSD UFS/UFS2" }, 76 { GPT_ENT_TYPE_FREEBSD_VINUM, "fbsd-vinum", "FreeBSD vinum" }, 77 { GPT_ENT_TYPE_FREEBSD_ZFS, "zfs", "ZFS" }, 78 { GPT_ENT_TYPE_LINUX_DATA, "linux-data", "Linux data" }, 79 { GPT_ENT_TYPE_LINUX_RAID, "linux-raid", "Linux RAID" }, 80 { GPT_ENT_TYPE_LINUX_SWAP, "linux-swap", "Linux swap" }, 81 { GPT_ENT_TYPE_LINUX_LVM, "linux-lvm", "Linux LVM" }, 82 { GPT_ENT_TYPE_MS_BASIC_DATA, "windows", "Windows basic data" }, 83 { GPT_ENT_TYPE_MS_RESERVED, "windows-reserved", "Windows reserved" }, 84 { GPT_ENT_TYPE_MS_RECOVERY, "windows-recovery", "Windows recovery" }, 85 { GPT_ENT_TYPE_NETBSD_CCD, "ccd", "NetBSD ccd component" }, 86 { GPT_ENT_TYPE_NETBSD_CGD, "cgd", "NetBSD Cryptographic Disk" }, 87 { GPT_ENT_TYPE_NETBSD_FFS, "ffs", "NetBSD FFSv1/FFSv2" }, 88 { GPT_ENT_TYPE_NETBSD_LFS, "lfs", "NetBSD LFS" }, 89 { GPT_ENT_TYPE_NETBSD_RAIDFRAME, "raid", 90 "NetBSD RAIDFrame component" }, 91 { GPT_ENT_TYPE_NETBSD_SWAP, "swap", "NetBSD swap" }, 92 { GPT_ENT_TYPE_OPENBSD_DATA, "obsd", "OpenBSD data" }, 93 { GPT_ENT_TYPE_VMWARE_VMKCORE, "vmcore", "VMware VMkernel core dump" }, 94 { GPT_ENT_TYPE_VMWARE_VMFS, "vmfs", "VMware VMFS" }, 95 { GPT_ENT_TYPE_VMWARE_RESERVED, "vmresered", "VMware reserved" }, 96 }; 97 98 static void 99 gpt_uuid_to_dce(const gpt_uuid_t buf, struct dce_uuid *uuid) 100 { 101 const uint8_t *p = buf; 102 size_t i; 103 104 uuid->time_low = le32dec(p); 105 uuid->time_mid = le16dec(p + 4); 106 uuid->time_hi_and_version = le16dec(p + 6); 107 uuid->clock_seq_hi_and_reserved = p[8]; 108 uuid->clock_seq_low = p[9]; 109 for (i = 0; i < sizeof(uuid->node); i++) 110 uuid->node[i] = p[10 + i]; 111 } 112 113 static void 114 gpt_dce_to_uuid(const struct dce_uuid *uuid, uint8_t *buf) 115 { 116 uint8_t *p = buf; 117 size_t i; 118 119 le32enc(p, uuid->time_low); 120 le16enc(p + 4, uuid->time_mid); 121 le16enc(p + 6, uuid->time_hi_and_version); 122 p[8] = uuid->clock_seq_hi_and_reserved; 123 p[9] = uuid->clock_seq_low; 124 for (i = 0; i < sizeof(uuid->node); i++) 125 p[10 + i] = uuid->node[i]; 126 } 127 128 static int 129 gpt_uuid_numeric(char *buf, size_t bufsiz, const struct dce_uuid *u) 130 { 131 return snprintf(buf, bufsiz, 132 "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x", 133 u->time_low, u->time_mid, u->time_hi_and_version, 134 u->clock_seq_hi_and_reserved, u->clock_seq_low, u->node[0], 135 u->node[1], u->node[2], u->node[3], u->node[4], u->node[5]); 136 } 137 138 139 static int 140 gpt_uuid_symbolic(char *buf, size_t bufsiz, const struct dce_uuid *u) 141 { 142 size_t i; 143 144 for (i = 0; i < __arraycount(gpt_nv); i++) 145 if (memcmp(&gpt_nv[i].u, u, sizeof(*u)) == 0) 146 return (int)strlcpy(buf, gpt_nv[i].n, bufsiz); 147 return -1; 148 } 149 150 static int 151 gpt_uuid_descriptive(char *buf, size_t bufsiz, const struct dce_uuid *u) 152 { 153 size_t i; 154 155 for (i = 0; i < __arraycount(gpt_nv); i++) 156 if (memcmp(&gpt_nv[i].u, u, sizeof(*u)) == 0) 157 return (int)strlcpy(buf, gpt_nv[i].d, bufsiz); 158 return -1; 159 } 160 161 int 162 gpt_uuid_snprintf(char *buf, size_t bufsiz, const char *fmt, 163 const gpt_uuid_t uu) 164 { 165 struct dce_uuid u; 166 gpt_uuid_to_dce(uu, &u); 167 168 if (fmt[1] == 's') { 169 int r; 170 if ((r = gpt_uuid_symbolic(buf, bufsiz, &u)) != -1) 171 return r; 172 } 173 if (fmt[1] == 'l') { 174 int r; 175 if ((r = gpt_uuid_descriptive(buf, bufsiz, &u)) != -1) 176 return r; 177 } 178 return gpt_uuid_numeric(buf, bufsiz, &u); 179 } 180 181 static int 182 gpt_uuid_parse_numeric(const char *s, struct dce_uuid *u) 183 { 184 int n; 185 186 if (s == NULL || *s == '\0') { 187 memset(u, 0, sizeof(*u)); 188 return 0; 189 } 190 191 n = sscanf(s, 192 "%8x-%4hx-%4hx-%2hhx%2hhx-%2hhx%2hhx%2hhx%2hhx%2hhx%2hhx", 193 &u->time_low, &u->time_mid, &u->time_hi_and_version, 194 &u->clock_seq_hi_and_reserved, &u->clock_seq_low, &u->node[0], 195 &u->node[1], &u->node[2], &u->node[3], &u->node[4], &u->node[5]); 196 197 /* Make sure we have all conversions. */ 198 if (n != 11) 199 return -1; 200 201 /* We have a successful scan. Check semantics... */ 202 n = u->clock_seq_hi_and_reserved; 203 if ((n & 0x80) != 0x00 && /* variant 0? */ 204 (n & 0xc0) != 0x80 && /* variant 1? */ 205 (n & 0xe0) != 0xc0) /* variant 2? */ 206 return -1; 207 return 0; 208 } 209 210 static int 211 gpt_uuid_parse_symbolic(const char *s, struct dce_uuid *u) 212 { 213 size_t i; 214 215 for (i = 0; i < __arraycount(gpt_nv); i++) 216 if (strcmp(gpt_nv[i].n, s) == 0) { 217 *u = gpt_nv[i].u; 218 return 0; 219 } 220 return -1; 221 } 222 223 int 224 gpt_uuid_parse(const char *s, gpt_uuid_t uuid) 225 { 226 struct dce_uuid u; 227 228 if (gpt_uuid_parse_numeric(s, &u) != -1) { 229 gpt_dce_to_uuid(&u, uuid); 230 return 0; 231 } 232 233 if (gpt_uuid_parse_symbolic(s, &u) == -1) 234 return -1; 235 236 gpt_dce_to_uuid(&u, uuid); 237 return 0; 238 } 239 240 size_t 241 gpt_uuid_query( 242 void (*func)(const char *uuid, const char *short_name, const char *desc)) 243 { 244 size_t i; 245 char buf[64]; 246 247 if (func != NULL) { 248 for (i = 0; i < __arraycount(gpt_nv); i++) { 249 gpt_uuid_numeric(buf, sizeof(buf), &gpt_nv[i].u); 250 (*func)(buf, gpt_nv[i].n, gpt_nv[i].d); 251 } 252 } 253 return __arraycount(gpt_nv); 254 } 255 256 #ifndef GPT_UUID_QUERY_ONLY 257 void 258 gpt_uuid_help(const char *prefix) 259 { 260 size_t i; 261 262 for (i = 0; i < __arraycount(gpt_nv); i++) 263 printf("%s%18.18s\t%s\n", prefix, gpt_nv[i].n, gpt_nv[i].d); 264 } 265 266 void 267 gpt_uuid_create(gpt_type_t t, gpt_uuid_t u, uint16_t *b, size_t s) 268 { 269 gpt_dce_to_uuid(&gpt_nv[t].u, u); 270 if (b) 271 utf8_to_utf16((const uint8_t *)gpt_nv[t].d, b, s / sizeof(*b)); 272 } 273 274 static int 275 gpt_uuid_random(gpt_t gpt, struct dce_uuid *u, size_t n) 276 { 277 int fd; 278 uint8_t *p; 279 ssize_t nread; 280 281 /* Randomly generate the content. */ 282 fd = open("/dev/urandom", O_RDONLY | O_CLOEXEC); 283 if (fd == -1) { 284 gpt_warn(gpt, "Can't open `/dev/urandom'"); 285 return -1; 286 } 287 for (p = (uint8_t *)u; n > 0; p += nread, n -= (size_t)nread) { 288 nread = read(fd, p, n); 289 if (nread < 0) { 290 gpt_warn(gpt, "Can't read `/dev/urandom'"); 291 goto out; 292 } 293 if (nread == 0) { 294 gpt_warn(gpt, "EOF from /dev/urandom"); 295 goto out; 296 } 297 if ((size_t)nread > n) { 298 gpt_warnx(gpt, "read too much: %zd > %zu", nread, n); 299 goto out; 300 } 301 } 302 (void)close(fd); 303 304 /* Set the version number to 4. */ 305 u->time_hi_and_version &= (uint16_t)~0xf000; 306 u->time_hi_and_version |= 0x4000; 307 308 return 0; 309 out: 310 (void)close(fd); 311 return -1; 312 } 313 314 /* 315 * For reproducible builds, we can base UUIDs on one external timestamp. 316 * 317 * Bump timestamp by one 100ns unit to make them unique within a GPT. 318 * Use zero clock sequence and node id, ideally these should also be 319 * passed as input. 320 */ 321 static int 322 gpt_uuid_tstamp(gpt_t gpt, struct dce_uuid *u, size_t l) 323 { 324 uint64_t x; 325 326 /* check for underflow/overflow of 60bit UUID time */ 327 if (gpt->timestamp < -12219292800 || 328 gpt->timestamp > 103072857660) 329 return -1; 330 331 /* 332 * Convert to UUID epoch (Gregorian) 333 * and 100ns units 334 */ 335 x = (uint64_t)(gpt->timestamp + 12219292800) * 10000000; 336 337 /* Make UUID unique */ 338 x += gpt->uuidgen++; 339 340 /* Set UUID fields for version 1 */ 341 u->time_low = x & 0xffffffff; 342 u->time_mid = (x >> 32) & 0xffff; 343 u->time_hi_and_version = 0x1000 | ((x >> 48) & 0xfff); 344 345 /* 346 * The clock sequence should make UUIDs unique in case 347 * the clock went backwards. 348 */ 349 u->clock_seq_hi_and_reserved = 0; 350 u->clock_seq_low = 0; 351 352 /* 353 * A unique system identifier (usually MAC address) 354 */ 355 memset(u->node, 0, sizeof(u->node)); 356 357 return 0; 358 } 359 360 int 361 gpt_uuid_generate(gpt_t gpt, gpt_uuid_t t) 362 { 363 int rv; 364 struct dce_uuid u; 365 366 if (gpt && (gpt->flags & GPT_TIMESTAMP)) 367 rv = gpt_uuid_tstamp(gpt, &u, sizeof(u)); 368 else 369 rv = gpt_uuid_random(gpt, &u, sizeof(u)); 370 371 if (rv == -1) 372 return -1; 373 374 /* Fix the reserved bits. */ 375 u.clock_seq_hi_and_reserved &= (uint8_t)~0x40; 376 u.clock_seq_hi_and_reserved |= 0x80; 377 378 gpt_dce_to_uuid(&u, t); 379 return 0; 380 } 381 #endif 382