kern_uuid.c revision 253590
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 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/sys/kern/kern_uuid.c 253590 2013-07-24 04:24:21Z marcel $"); 29 30#include <sys/param.h> 31#include <sys/endian.h> 32#include <sys/kernel.h> 33#include <sys/lock.h> 34#include <sys/mutex.h> 35#include <sys/sbuf.h> 36#include <sys/socket.h> 37#include <sys/sysproto.h> 38#include <sys/systm.h> 39#include <sys/jail.h> 40#include <sys/uuid.h> 41 42#include <net/if.h> 43#include <net/if_dl.h> 44#include <net/if_types.h> 45#include <net/vnet.h> 46 47/* 48 * See also: 49 * http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt 50 * http://www.opengroup.org/onlinepubs/009629399/apdxa.htm 51 * 52 * Note that the generator state is itself an UUID, but the time and clock 53 * sequence fields are written in the native byte order. 54 */ 55 56CTASSERT(sizeof(struct uuid) == 16); 57 58/* We use an alternative, more convenient representation in the generator. */ 59struct uuid_private { 60 union { 61 uint64_t ll; /* internal. */ 62 struct { 63 uint32_t low; 64 uint16_t mid; 65 uint16_t hi; 66 } x; 67 } time; 68 uint16_t seq; /* Big-endian. */ 69 uint16_t node[UUID_NODE_LEN>>1]; 70}; 71 72CTASSERT(sizeof(struct uuid_private) == 16); 73 74struct uuid_macaddr { 75 uint16_t state; 76#define UUID_ETHER_EMPTY 0 77#define UUID_ETHER_RANDOM 1 78#define UUID_ETHER_UNIQUE 2 79 uint16_t node[UUID_NODE_LEN>>1]; 80}; 81 82static struct uuid_private uuid_last; 83 84#define UUID_NETHER 4 85static struct uuid_macaddr uuid_ether[UUID_NETHER]; 86 87static struct mtx uuid_mutex; 88MTX_SYSINIT(uuid_lock, &uuid_mutex, "UUID generator mutex lock", MTX_DEF); 89 90/* 91 * Return the first MAC address added in the array. If it's empty, then 92 * construct a sufficiently random multicast MAC address first. Any 93 * addresses added later will bump the random MAC address up tp the next 94 * index. 95 */ 96static void 97uuid_node(uint16_t *node) 98{ 99 int i; 100 101 if (uuid_ether[0].state == UUID_ETHER_EMPTY) { 102 for (i = 0; i < (UUID_NODE_LEN>>1); i++) 103 uuid_ether[0].node[i] = (uint16_t)arc4random(); 104 *((uint8_t*)uuid_ether[0].node) |= 0x01; 105 uuid_ether[0].state = UUID_ETHER_RANDOM; 106 } 107 for (i = 0; i < (UUID_NODE_LEN>>1); i++) 108 node[i] = uuid_ether[0].node[i]; 109} 110 111/* 112 * Get the current time as a 60 bit count of 100-nanosecond intervals 113 * since 00:00:00.00, October 15,1582. We apply a magic offset to convert 114 * the Unix time since 00:00:00.00, January 1, 1970 to the date of the 115 * Gregorian reform to the Christian calendar. 116 */ 117static uint64_t 118uuid_time(void) 119{ 120 struct bintime bt; 121 uint64_t time = 0x01B21DD213814000LL; 122 123 bintime(&bt); 124 time += (uint64_t)bt.sec * 10000000LL; 125 time += (10000000LL * (uint32_t)(bt.frac >> 32)) >> 32; 126 return (time & ((1LL << 60) - 1LL)); 127} 128 129struct uuid * 130kern_uuidgen(struct uuid *store, size_t count) 131{ 132 struct uuid_private uuid; 133 uint64_t time; 134 size_t n; 135 136 mtx_lock(&uuid_mutex); 137 138 uuid_node(uuid.node); 139 time = uuid_time(); 140 141 if (uuid_last.time.ll == 0LL || uuid_last.node[0] != uuid.node[0] || 142 uuid_last.node[1] != uuid.node[1] || 143 uuid_last.node[2] != uuid.node[2]) 144 uuid.seq = (uint16_t)arc4random() & 0x3fff; 145 else if (uuid_last.time.ll >= time) 146 uuid.seq = (uuid_last.seq + 1) & 0x3fff; 147 else 148 uuid.seq = uuid_last.seq; 149 150 uuid_last = uuid; 151 uuid_last.time.ll = (time + count - 1) & ((1LL << 60) - 1LL); 152 153 mtx_unlock(&uuid_mutex); 154 155 /* Set sequence and variant and deal with byte order. */ 156 uuid.seq = htobe16(uuid.seq | 0x8000); 157 158 for (n = 0; n < count; n++) { 159 /* Set time and version (=1). */ 160 uuid.time.x.low = (uint32_t)time; 161 uuid.time.x.mid = (uint16_t)(time >> 32); 162 uuid.time.x.hi = ((uint16_t)(time >> 48) & 0xfff) | (1 << 12); 163 store[n] = *(struct uuid *)&uuid; 164 time++; 165 } 166 167 return (store); 168} 169 170#ifndef _SYS_SYSPROTO_H_ 171struct uuidgen_args { 172 struct uuid *store; 173 int count; 174}; 175#endif 176int 177sys_uuidgen(struct thread *td, struct uuidgen_args *uap) 178{ 179 struct uuid *store; 180 size_t count; 181 int error; 182 183 /* 184 * Limit the number of UUIDs that can be created at the same time 185 * to some arbitrary number. This isn't really necessary, but I 186 * like to have some sort of upper-bound that's less than 2G :-) 187 * XXX probably needs to be tunable. 188 */ 189 if (uap->count < 1 || uap->count > 2048) 190 return (EINVAL); 191 192 count = uap->count; 193 store = malloc(count * sizeof(struct uuid), M_TEMP, M_WAITOK); 194 kern_uuidgen(store, count); 195 error = copyout(store, uap->store, count * sizeof(struct uuid)); 196 free(store, M_TEMP); 197 return (error); 198} 199 200int 201uuid_ether_add(const uint8_t *addr) 202{ 203 int i; 204 uint8_t c; 205 206 /* 207 * Validate input. No multicast addresses and no addresses that 208 * are all zeroes. 209 */ 210 if (addr[0] & 0x01) 211 return (EINVAL); 212 c = 0; 213 for (i = 0; i < UUID_NODE_LEN; i++) 214 c += addr[i]; 215 if (c == 0) 216 return (EINVAL); 217 218 mtx_lock(&uuid_mutex); 219 220 /* Make sure the MAC isn't known already and that there's space. */ 221 i = 0; 222 while (i < UUID_NETHER && uuid_ether[i].state == UUID_ETHER_UNIQUE) { 223 if (!bcmp(addr, uuid_ether[i].node, UUID_NODE_LEN)) { 224 mtx_unlock(&uuid_mutex); 225 return (EEXIST); 226 } 227 i++; 228 } 229 if (i == UUID_NETHER) { 230 mtx_unlock(&uuid_mutex); 231 return (ENOSPC); 232 } 233 234 /* Insert MAC at index, moving the non-empty entry if possible. */ 235 if (uuid_ether[i].state == UUID_ETHER_RANDOM && i < UUID_NETHER - 1) 236 uuid_ether[i + 1] = uuid_ether[i]; 237 uuid_ether[i].state = UUID_ETHER_UNIQUE; 238 bcopy(addr, uuid_ether[i].node, UUID_NODE_LEN); 239 mtx_unlock(&uuid_mutex); 240 return (0); 241} 242 243int 244uuid_ether_del(const uint8_t *addr) 245{ 246 int i; 247 248 mtx_lock(&uuid_mutex); 249 i = 0; 250 while (i < UUID_NETHER && uuid_ether[i].state == UUID_ETHER_UNIQUE && 251 bcmp(addr, uuid_ether[i].node, UUID_NODE_LEN)) 252 i++; 253 if (i == UUID_NETHER || uuid_ether[i].state != UUID_ETHER_UNIQUE) { 254 mtx_unlock(&uuid_mutex); 255 return (ENOENT); 256 } 257 258 /* Remove it by shifting higher index entries down. */ 259 while (i < UUID_NETHER - 1 && uuid_ether[i].state != UUID_ETHER_EMPTY) { 260 uuid_ether[i] = uuid_ether[i + 1]; 261 i++; 262 } 263 if (uuid_ether[i].state != UUID_ETHER_EMPTY) { 264 uuid_ether[i].state = UUID_ETHER_EMPTY; 265 bzero(uuid_ether[i].node, UUID_NODE_LEN); 266 } 267 mtx_unlock(&uuid_mutex); 268 return (0); 269} 270 271int 272snprintf_uuid(char *buf, size_t sz, struct uuid *uuid) 273{ 274 struct uuid_private *id; 275 int cnt; 276 277 id = (struct uuid_private *)uuid; 278 cnt = snprintf(buf, sz, "%08x-%04x-%04x-%04x-%04x%04x%04x", 279 id->time.x.low, id->time.x.mid, id->time.x.hi, be16toh(id->seq), 280 be16toh(id->node[0]), be16toh(id->node[1]), be16toh(id->node[2])); 281 return (cnt); 282} 283 284int 285printf_uuid(struct uuid *uuid) 286{ 287 char buf[38]; 288 289 snprintf_uuid(buf, sizeof(buf), uuid); 290 return (printf("%s", buf)); 291} 292 293int 294sbuf_printf_uuid(struct sbuf *sb, struct uuid *uuid) 295{ 296 char buf[38]; 297 298 snprintf_uuid(buf, sizeof(buf), uuid); 299 return (sbuf_printf(sb, "%s", buf)); 300} 301 302/* 303 * Encode/Decode UUID into byte-stream. 304 * http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt 305 * 306 * 0 1 2 3 307 * 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 1 308 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 309 * | time_low | 310 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 311 * | time_mid | time_hi_and_version | 312 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 313 * |clk_seq_hi_res | clk_seq_low | node (0-1) | 314 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 315 * | node (2-5) | 316 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 317 */ 318 319void 320le_uuid_enc(void *buf, struct uuid const *uuid) 321{ 322 u_char *p; 323 int i; 324 325 p = buf; 326 le32enc(p, uuid->time_low); 327 le16enc(p + 4, uuid->time_mid); 328 le16enc(p + 6, uuid->time_hi_and_version); 329 p[8] = uuid->clock_seq_hi_and_reserved; 330 p[9] = uuid->clock_seq_low; 331 for (i = 0; i < _UUID_NODE_LEN; i++) 332 p[10 + i] = uuid->node[i]; 333} 334 335void 336le_uuid_dec(void const *buf, struct uuid *uuid) 337{ 338 u_char const *p; 339 int i; 340 341 p = buf; 342 uuid->time_low = le32dec(p); 343 uuid->time_mid = le16dec(p + 4); 344 uuid->time_hi_and_version = le16dec(p + 6); 345 uuid->clock_seq_hi_and_reserved = p[8]; 346 uuid->clock_seq_low = p[9]; 347 for (i = 0; i < _UUID_NODE_LEN; i++) 348 uuid->node[i] = p[10 + i]; 349} 350 351void 352be_uuid_enc(void *buf, struct uuid const *uuid) 353{ 354 u_char *p; 355 int i; 356 357 p = buf; 358 be32enc(p, uuid->time_low); 359 be16enc(p + 4, uuid->time_mid); 360 be16enc(p + 6, uuid->time_hi_and_version); 361 p[8] = uuid->clock_seq_hi_and_reserved; 362 p[9] = uuid->clock_seq_low; 363 for (i = 0; i < _UUID_NODE_LEN; i++) 364 p[10 + i] = uuid->node[i]; 365} 366 367void 368be_uuid_dec(void const *buf, struct uuid *uuid) 369{ 370 u_char const *p; 371 int i; 372 373 p = buf; 374 uuid->time_low = be32dec(p); 375 uuid->time_mid = le16dec(p + 4); 376 uuid->time_hi_and_version = be16dec(p + 6); 377 uuid->clock_seq_hi_and_reserved = p[8]; 378 uuid->clock_seq_low = p[9]; 379 for (i = 0; i < _UUID_NODE_LEN; i++) 380 uuid->node[i] = p[10 + i]; 381} 382 383int 384parse_uuid(const char *str, struct uuid *uuid) 385{ 386 u_int c[11]; 387 int n; 388 389 /* An empty string represents a nil UUID. */ 390 if (*str == '\0') { 391 bzero(uuid, sizeof(*uuid)); 392 return (0); 393 } 394 395 /* The UUID string representation has a fixed length. */ 396 if (strlen(str) != 36) 397 return (EINVAL); 398 399 /* 400 * We only work with "new" UUIDs. New UUIDs have the form: 401 * 01234567-89ab-cdef-0123-456789abcdef 402 * The so called "old" UUIDs, which we don't support, have the form: 403 * 0123456789ab.cd.ef.01.23.45.67.89.ab 404 */ 405 if (str[8] != '-') 406 return (EINVAL); 407 408 n = sscanf(str, "%8x-%4x-%4x-%2x%2x-%2x%2x%2x%2x%2x%2x", c + 0, c + 1, 409 c + 2, c + 3, c + 4, c + 5, c + 6, c + 7, c + 8, c + 9, c + 10); 410 /* Make sure we have all conversions. */ 411 if (n != 11) 412 return (EINVAL); 413 414 /* Successful scan. Build the UUID. */ 415 uuid->time_low = c[0]; 416 uuid->time_mid = c[1]; 417 uuid->time_hi_and_version = c[2]; 418 uuid->clock_seq_hi_and_reserved = c[3]; 419 uuid->clock_seq_low = c[4]; 420 for (n = 0; n < 6; n++) 421 uuid->node[n] = c[n + 5]; 422 423 /* Check semantics... */ 424 return (((c[3] & 0x80) != 0x00 && /* variant 0? */ 425 (c[3] & 0xc0) != 0x80 && /* variant 1? */ 426 (c[3] & 0xe0) != 0xc0) ? EINVAL : 0); /* variant 2? */ 427} 428