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); 176 kern_uuidgen(store, count); 177 error = copyout(store, uap->store, count * sizeof(struct uuid)); 178 kfree(store, M_TEMP); 179 return (error); 180 } 181 182 int 183 snprintf_uuid(char *buf, size_t sz, struct uuid *uuid) 184 { 185 struct uuid_private *id; 186 int cnt; 187 188 id = (struct uuid_private *)uuid; 189 cnt = ksnprintf(buf, sz, "%08x-%04x-%04x-%04x-%04x%04x%04x", 190 id->time.x.low, id->time.x.mid, id->time.x.hi, be16toh(id->seq), 191 be16toh(id->node[0]), be16toh(id->node[1]), be16toh(id->node[2])); 192 return (cnt); 193 } 194 195 int 196 printf_uuid(struct uuid *uuid) 197 { 198 char buf[38]; 199 200 snprintf_uuid(buf, sizeof(buf), uuid); 201 return (kprintf("%s", buf)); 202 } 203 204 int 205 sbuf_printf_uuid(struct sbuf *sb, struct uuid *uuid) 206 { 207 char buf[38]; 208 209 snprintf_uuid(buf, sizeof(buf), uuid); 210 return (sbuf_printf(sb, "%s", buf)); 211 } 212 213 /* 214 * Test functions 215 */ 216 217 /* A macro used to improve the readability of uuid_compare(). */ 218 #define DIFF_RETURN(a, b, field) do { \ 219 if ((a)->field != (b)->field) \ 220 return (((a)->field < (b)->field) ? -1 : 1); \ 221 } while (0) 222 223 /* 224 * kuuid_compare() - compare two UUIDs. 225 * See also: 226 * http://www.opengroup.org/onlinepubs/009629399/uuid_compare.htm 227 * 228 * NOTE: Either UUID can be NULL, meaning a nil UUID. nil UUIDs are smaller 229 * than any non-nil UUID. 230 */ 231 int 232 kuuid_compare(const struct uuid *a, const struct uuid *b) 233 { 234 int res; 235 236 /* Deal with NULL or equal pointers. */ 237 if (a == b) 238 return (0); 239 if (a == NULL) 240 return ((kuuid_is_nil(b)) ? 0 : -1); 241 if (b == NULL) 242 return ((kuuid_is_nil(a)) ? 0 : 1); 243 244 /* We have to compare the hard way. */ 245 DIFF_RETURN(a, b, time_low); 246 DIFF_RETURN(a, b, time_mid); 247 DIFF_RETURN(a, b, time_hi_and_version); 248 DIFF_RETURN(a, b, clock_seq_hi_and_reserved); 249 DIFF_RETURN(a, b, clock_seq_low); 250 251 res = bcmp(a->node, b->node, sizeof(a->node)); 252 if (res) 253 return ((res < 0) ? -1 : 1); 254 return (0); 255 } 256 257 #undef DIFF_RETURN 258 259 int 260 kuuid_is_nil(const struct uuid *uuid) 261 { 262 int i; 263 264 for (i = 0; i < sizeof(*uuid); i += sizeof(int)) { 265 if (*(const int *)((const char *)uuid + i) != 0) 266 return(0); 267 } 268 return(1); 269 } 270 271 int 272 kuuid_is_ccd(const struct uuid *uuid) 273 { 274 static struct uuid ccd_uuid = GPT_ENT_TYPE_DRAGONFLY_CCD; 275 return(kuuid_compare(uuid, &ccd_uuid) == 0); 276 } 277 278 int 279 kuuid_is_vinum(const struct uuid *uuid) 280 { 281 static struct uuid vinum_uuid = GPT_ENT_TYPE_DRAGONFLY_VINUM; 282 return(kuuid_compare(uuid, &vinum_uuid) == 0); 283 } 284 285 /* 286 * Encode/Decode UUID into byte-stream. 287 * http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt 288 * 289 * 0 1 2 3 290 * 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 1 291 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 292 * | time_low | 293 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 294 * | time_mid | time_hi_and_version | 295 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 296 * |clk_seq_hi_res | clk_seq_low | node (0-1) | 297 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 298 * | node (2-5) | 299 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 300 */ 301 302 void 303 le_uuid_enc(void *buf, struct uuid const *uuid) 304 { 305 u_char *p; 306 int i; 307 308 p = buf; 309 le32enc(p, uuid->time_low); 310 le16enc(p + 4, uuid->time_mid); 311 le16enc(p + 6, uuid->time_hi_and_version); 312 p[8] = uuid->clock_seq_hi_and_reserved; 313 p[9] = uuid->clock_seq_low; 314 for (i = 0; i < _UUID_NODE_LEN; i++) 315 p[10 + i] = uuid->node[i]; 316 } 317 318 void 319 le_uuid_dec(void const *buf, struct uuid *uuid) 320 { 321 u_char const *p; 322 int i; 323 324 p = buf; 325 uuid->time_low = le32dec(p); 326 uuid->time_mid = le16dec(p + 4); 327 uuid->time_hi_and_version = le16dec(p + 6); 328 uuid->clock_seq_hi_and_reserved = p[8]; 329 uuid->clock_seq_low = p[9]; 330 for (i = 0; i < _UUID_NODE_LEN; i++) 331 uuid->node[i] = p[10 + i]; 332 } 333 334 void 335 be_uuid_enc(void *buf, struct uuid const *uuid) 336 { 337 u_char *p; 338 int i; 339 340 p = buf; 341 be32enc(p, uuid->time_low); 342 be16enc(p + 4, uuid->time_mid); 343 be16enc(p + 6, uuid->time_hi_and_version); 344 p[8] = uuid->clock_seq_hi_and_reserved; 345 p[9] = uuid->clock_seq_low; 346 for (i = 0; i < _UUID_NODE_LEN; i++) 347 p[10 + i] = uuid->node[i]; 348 } 349 350 void 351 be_uuid_dec(void const *buf, struct uuid *uuid) 352 { 353 u_char const *p; 354 int i; 355 356 p = buf; 357 uuid->time_low = be32dec(p); 358 uuid->time_mid = le16dec(p + 4); 359 uuid->time_hi_and_version = be16dec(p + 6); 360 uuid->clock_seq_hi_and_reserved = p[8]; 361 uuid->clock_seq_low = p[9]; 362 for (i = 0; i < _UUID_NODE_LEN; i++) 363 uuid->node[i] = p[10 + i]; 364 } 365 366 int 367 parse_uuid(const char *str, struct uuid *uuid) 368 { 369 u_int c[11]; 370 int n; 371 372 /* An empty string represents a nil UUID. */ 373 if (*str == '\0') { 374 bzero(uuid, sizeof(*uuid)); 375 return (0); 376 } 377 378 /* The UUID string representation has a fixed length. */ 379 if (strlen(str) != 36) 380 return (EINVAL); 381 382 /* 383 * We only work with "new" UUIDs. New UUIDs have the form: 384 * 01234567-89ab-cdef-0123-456789abcdef 385 * The so called "old" UUIDs, which we don't support, have the form: 386 * 0123456789ab.cd.ef.01.23.45.67.89.ab 387 */ 388 if (str[8] != '-') 389 return (EINVAL); 390 391 n = ksscanf(str, "%8x-%4x-%4x-%2x%2x-%2x%2x%2x%2x%2x%2x", c + 0, c + 1, 392 c + 2, c + 3, c + 4, c + 5, c + 6, c + 7, c + 8, c + 9, c + 10); 393 /* Make sure we have all conversions. */ 394 if (n != 11) 395 return (EINVAL); 396 397 /* Successful scan. Build the UUID. */ 398 uuid->time_low = c[0]; 399 uuid->time_mid = c[1]; 400 uuid->time_hi_and_version = c[2]; 401 uuid->clock_seq_hi_and_reserved = c[3]; 402 uuid->clock_seq_low = c[4]; 403 for (n = 0; n < 6; n++) 404 uuid->node[n] = c[n + 5]; 405 406 /* Check semantics... */ 407 return (((c[3] & 0x80) != 0x00 && /* variant 0? */ 408 (c[3] & 0xc0) != 0x80 && /* variant 1? */ 409 (c[3] & 0xe0) != 0xc0) ? EINVAL : 0); /* variant 2? */ 410 } 411