1 /*- 2 * Copyright (c) 2002 Marcel Moolenaar 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD: src/sys/kern/kern_uuid.c,v 1.13 2007/04/23 12:53:00 pjd Exp $ 27 * $DragonFly: src/sys/kern/kern_uuid.c,v 1.4 2007/06/19 06:07:57 dillon Exp $ 28 */ 29 30 #include <sys/param.h> 31 #include <sys/endian.h> 32 #include <sys/systm.h> 33 #include <sys/kernel.h> 34 #include <sys/lock.h> 35 #include <sys/kern_syscall.h> 36 #include <sys/random.h> 37 #include <sys/sbuf.h> 38 #include <sys/socket.h> 39 #include <sys/sysproto.h> 40 #include <sys/uuid.h> 41 #include <sys/gpt.h> 42 #include <net/if_var.h> 43 44 /* 45 * See also: 46 * http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt 47 * http://www.opengroup.org/onlinepubs/009629399/apdxa.htm 48 * 49 * Note that the generator state is itself an UUID, but the time and clock 50 * sequence fields are written in the native byte order. 51 */ 52 53 /* We use an alternative, more convenient representation in the generator. */ 54 struct uuid_private { 55 union { 56 uint64_t ll; /* internal. */ 57 struct { 58 uint32_t low; 59 uint16_t mid; 60 uint16_t hi; 61 } x; 62 } time; 63 uint16_t seq; /* Big-endian. */ 64 uint16_t node[UUID_NODE_LEN>>1]; 65 }; 66 67 static struct uuid_private uuid_last; 68 69 static struct lock uuid_lock; 70 71 static 72 void 73 uuid_lock_init(void *arg __unused) 74 { 75 lockinit(&uuid_lock, "uuid", 0, 0); 76 } 77 SYSINIT(uuid_lock, SI_BOOT1_POST, SI_ORDER_ANY, uuid_lock_init, NULL); 78 79 /* 80 * Ask the network subsystem for a real MAC address from any of the 81 * system interfaces. If we can't find one, generate a random multicast 82 * MAC address. 83 */ 84 static void 85 uuid_node(uint16_t *node) 86 { 87 if (if_getanyethermac(node, UUID_NODE_LEN) != 0) 88 read_random(node, UUID_NODE_LEN); 89 *((uint8_t*)node) |= 0x01; 90 } 91 92 /* 93 * Get the current time as a 60 bit count of 100-nanosecond intervals 94 * since 00:00:00.00, October 15,1582. We apply a magic offset to convert 95 * the Unix time since 00:00:00.00, January 1, 1970 to the date of the 96 * Gregorian reform to the Christian calendar. 97 */ 98 static uint64_t 99 uuid_time(void) 100 { 101 struct timespec ts; 102 uint64_t time = 0x01B21DD213814000LL; 103 104 nanotime(&ts); 105 time += ts.tv_sec * 10000000LL; /* 100 ns increments */ 106 time += ts.tv_nsec / 100; /* 100 ns increments */ 107 return (time & ((1LL << 60) - 1LL)); /* limit to 60 bits */ 108 } 109 110 struct uuid * 111 kern_uuidgen(struct uuid *store, size_t count) 112 { 113 struct uuid_private uuid; 114 uint64_t time; 115 size_t n; 116 117 lockmgr(&uuid_lock, LK_EXCLUSIVE | LK_RETRY); 118 119 uuid_node(uuid.node); 120 time = uuid_time(); 121 122 if (uuid_last.time.ll == 0LL || uuid_last.node[0] != uuid.node[0] || 123 uuid_last.node[1] != uuid.node[1] || 124 uuid_last.node[2] != uuid.node[2]) { 125 read_random(&uuid.seq, sizeof(uuid.seq)); 126 uuid.seq &= 0x3fff; 127 } else if (uuid_last.time.ll >= time) { 128 uuid.seq = (uuid_last.seq + 1) & 0x3fff; 129 } else { 130 uuid.seq = uuid_last.seq; 131 } 132 133 uuid_last = uuid; 134 uuid_last.time.ll = (time + count - 1) & ((1LL << 60) - 1LL); 135 136 lockmgr(&uuid_lock, LK_RELEASE); 137 138 /* Set sequence and variant and deal with byte order. */ 139 uuid.seq = htobe16(uuid.seq | 0x8000); 140 141 for (n = 0; n < count; n++) { 142 /* Set time and version (=1). */ 143 uuid.time.x.low = (uint32_t)time; 144 uuid.time.x.mid = (uint16_t)(time >> 32); 145 uuid.time.x.hi = ((uint16_t)(time >> 48) & 0xfff) | (1 << 12); 146 store[n] = *(struct uuid *)&uuid; 147 time++; 148 } 149 150 return (store); 151 } 152 153 /* 154 * uuidgen(struct uuid *store, int count) 155 * 156 * Generate an array of new UUIDs 157 */ 158 int 159 sys_uuidgen(struct uuidgen_args *uap) 160 { 161 struct uuid *store; 162 size_t count; 163 int error; 164 165 /* 166 * Limit the number of UUIDs that can be created at the same time 167 * to some arbitrary number. This isn't really necessary, but I 168 * like to have some sort of upper-bound that's less than 2G :-) 169 * XXX probably needs to be tunable. 170 */ 171 if (uap->count < 1 || uap->count > 2048) 172 return (EINVAL); 173 174 count = uap->count; 175 store = kmalloc(count * sizeof(struct uuid), M_TEMP, M_WAITOK|M_NULLOK); 176 if (store == NULL) 177 return (ENOSPC); 178 kern_uuidgen(store, count); 179 error = copyout(store, uap->store, count * sizeof(struct uuid)); 180 kfree(store, M_TEMP); 181 return (error); 182 } 183 184 int 185 snprintf_uuid(char *buf, size_t sz, struct uuid *uuid) 186 { 187 struct uuid_private *id; 188 int cnt; 189 190 id = (struct uuid_private *)uuid; 191 cnt = ksnprintf(buf, sz, "%08x-%04x-%04x-%04x-%04x%04x%04x", 192 id->time.x.low, id->time.x.mid, id->time.x.hi, be16toh(id->seq), 193 be16toh(id->node[0]), be16toh(id->node[1]), be16toh(id->node[2])); 194 return (cnt); 195 } 196 197 int 198 printf_uuid(struct uuid *uuid) 199 { 200 char buf[38]; 201 202 snprintf_uuid(buf, sizeof(buf), uuid); 203 return (kprintf("%s", buf)); 204 } 205 206 int 207 sbuf_printf_uuid(struct sbuf *sb, struct uuid *uuid) 208 { 209 char buf[38]; 210 211 snprintf_uuid(buf, sizeof(buf), uuid); 212 return (sbuf_printf(sb, "%s", buf)); 213 } 214 215 /* 216 * Test functions 217 */ 218 219 /* A macro used to improve the readability of uuid_compare(). */ 220 #define DIFF_RETURN(a, b, field) do { \ 221 if ((a)->field != (b)->field) \ 222 return (((a)->field < (b)->field) ? -1 : 1); \ 223 } while (0) 224 225 /* 226 * kuuid_compare() - compare two UUIDs. 227 * See also: 228 * http://www.opengroup.org/onlinepubs/009629399/uuid_compare.htm 229 * 230 * NOTE: Either UUID can be NULL, meaning a nil UUID. nil UUIDs are smaller 231 * than any non-nil UUID. 232 */ 233 int 234 kuuid_compare(const struct uuid *a, const struct uuid *b) 235 { 236 int res; 237 238 /* Deal with NULL or equal pointers. */ 239 if (a == b) 240 return (0); 241 if (a == NULL) 242 return ((kuuid_is_nil(b)) ? 0 : -1); 243 if (b == NULL) 244 return ((kuuid_is_nil(a)) ? 0 : 1); 245 246 /* We have to compare the hard way. */ 247 DIFF_RETURN(a, b, time_low); 248 DIFF_RETURN(a, b, time_mid); 249 DIFF_RETURN(a, b, time_hi_and_version); 250 DIFF_RETURN(a, b, clock_seq_hi_and_reserved); 251 DIFF_RETURN(a, b, clock_seq_low); 252 253 res = bcmp(a->node, b->node, sizeof(a->node)); 254 if (res) 255 return ((res < 0) ? -1 : 1); 256 return (0); 257 } 258 259 #undef DIFF_RETURN 260 261 int 262 kuuid_is_nil(const struct uuid *uuid) 263 { 264 int i; 265 266 for (i = 0; i < sizeof(*uuid); i += sizeof(int)) { 267 if (*(const int *)((const char *)uuid + i) != 0) 268 return(0); 269 } 270 return(1); 271 } 272 273 int 274 kuuid_is_ccd(const struct uuid *uuid) 275 { 276 static struct uuid ccd_uuid = GPT_ENT_TYPE_DRAGONFLY_CCD; 277 return(kuuid_compare(uuid, &ccd_uuid) == 0); 278 } 279 280 int 281 kuuid_is_vinum(const struct uuid *uuid) 282 { 283 static struct uuid vinum_uuid = GPT_ENT_TYPE_DRAGONFLY_VINUM; 284 return(kuuid_compare(uuid, &vinum_uuid) == 0); 285 } 286 287 /* 288 * Encode/Decode UUID into byte-stream. 289 * http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt 290 * 291 * 0 1 2 3 292 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 293 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 294 * | time_low | 295 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 296 * | time_mid | time_hi_and_version | 297 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 298 * |clk_seq_hi_res | clk_seq_low | node (0-1) | 299 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 300 * | node (2-5) | 301 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 302 */ 303 304 void 305 le_uuid_enc(void *buf, struct uuid const *uuid) 306 { 307 u_char *p; 308 int i; 309 310 p = buf; 311 le32enc(p, uuid->time_low); 312 le16enc(p + 4, uuid->time_mid); 313 le16enc(p + 6, uuid->time_hi_and_version); 314 p[8] = uuid->clock_seq_hi_and_reserved; 315 p[9] = uuid->clock_seq_low; 316 for (i = 0; i < _UUID_NODE_LEN; i++) 317 p[10 + i] = uuid->node[i]; 318 } 319 320 void 321 le_uuid_dec(void const *buf, struct uuid *uuid) 322 { 323 u_char const *p; 324 int i; 325 326 p = buf; 327 uuid->time_low = le32dec(p); 328 uuid->time_mid = le16dec(p + 4); 329 uuid->time_hi_and_version = le16dec(p + 6); 330 uuid->clock_seq_hi_and_reserved = p[8]; 331 uuid->clock_seq_low = p[9]; 332 for (i = 0; i < _UUID_NODE_LEN; i++) 333 uuid->node[i] = p[10 + i]; 334 } 335 336 void 337 be_uuid_enc(void *buf, struct uuid const *uuid) 338 { 339 u_char *p; 340 int i; 341 342 p = buf; 343 be32enc(p, uuid->time_low); 344 be16enc(p + 4, uuid->time_mid); 345 be16enc(p + 6, uuid->time_hi_and_version); 346 p[8] = uuid->clock_seq_hi_and_reserved; 347 p[9] = uuid->clock_seq_low; 348 for (i = 0; i < _UUID_NODE_LEN; i++) 349 p[10 + i] = uuid->node[i]; 350 } 351 352 void 353 be_uuid_dec(void const *buf, struct uuid *uuid) 354 { 355 u_char const *p; 356 int i; 357 358 p = buf; 359 uuid->time_low = be32dec(p); 360 uuid->time_mid = le16dec(p + 4); 361 uuid->time_hi_and_version = be16dec(p + 6); 362 uuid->clock_seq_hi_and_reserved = p[8]; 363 uuid->clock_seq_low = p[9]; 364 for (i = 0; i < _UUID_NODE_LEN; i++) 365 uuid->node[i] = p[10 + i]; 366 } 367 368 int 369 parse_uuid(const char *str, struct uuid *uuid) 370 { 371 u_int c[11]; 372 int n; 373 374 /* An empty string represents a nil UUID. */ 375 if (*str == '\0') { 376 bzero(uuid, sizeof(*uuid)); 377 return (0); 378 } 379 380 /* The UUID string representation has a fixed length. */ 381 if (strlen(str) != 36) 382 return (EINVAL); 383 384 /* 385 * We only work with "new" UUIDs. New UUIDs have the form: 386 * 01234567-89ab-cdef-0123-456789abcdef 387 * The so called "old" UUIDs, which we don't support, have the form: 388 * 0123456789ab.cd.ef.01.23.45.67.89.ab 389 */ 390 if (str[8] != '-') 391 return (EINVAL); 392 393 n = ksscanf(str, "%8x-%4x-%4x-%2x%2x-%2x%2x%2x%2x%2x%2x", c + 0, c + 1, 394 c + 2, c + 3, c + 4, c + 5, c + 6, c + 7, c + 8, c + 9, c + 10); 395 /* Make sure we have all conversions. */ 396 if (n != 11) 397 return (EINVAL); 398 399 /* Successful scan. Build the UUID. */ 400 uuid->time_low = c[0]; 401 uuid->time_mid = c[1]; 402 uuid->time_hi_and_version = c[2]; 403 uuid->clock_seq_hi_and_reserved = c[3]; 404 uuid->clock_seq_low = c[4]; 405 for (n = 0; n < 6; n++) 406 uuid->node[n] = c[n + 5]; 407 408 /* Check semantics... */ 409 return (((c[3] & 0x80) != 0x00 && /* variant 0? */ 410 (c[3] & 0xc0) != 0x80 && /* variant 1? */ 411 (c[3] & 0xe0) != 0xc0) ? EINVAL : 0); /* variant 2? */ 412 } 413