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("$FreeBSD$"); 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/uuid.h> 40 #include <sys/vimage.h> 41 42 #include <net/if.h> 43 #include <net/if_dl.h> 44 #include <net/if_types.h> 45 #include <net/route.h> 46 #include <net/vnet.h> 47 48 /* 49 * See also: 50 * http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt 51 * http://www.opengroup.org/onlinepubs/009629399/apdxa.htm 52 * 53 * Note that the generator state is itself an UUID, but the time and clock 54 * sequence fields are written in the native byte order. 55 */ 56 57 CTASSERT(sizeof(struct uuid) == 16); 58 59 /* We use an alternative, more convenient representation in the generator. */ 60 struct uuid_private { 61 union { 62 uint64_t ll; /* internal. */ 63 struct { 64 uint32_t low; 65 uint16_t mid; 66 uint16_t hi; 67 } x; 68 } time; 69 uint16_t seq; /* Big-endian. */ 70 uint16_t node[UUID_NODE_LEN>>1]; 71 }; 72 73 CTASSERT(sizeof(struct uuid_private) == 16); 74 75 static struct uuid_private uuid_last; 76 77 static struct mtx uuid_mutex; 78 MTX_SYSINIT(uuid_lock, &uuid_mutex, "UUID generator mutex lock", MTX_DEF); 79 80 /* 81 * Return the first MAC address we encounter or, if none was found, 82 * construct a sufficiently random multicast address. We don't try 83 * to return the same MAC address as previously returned. We always 84 * generate a new multicast address if no MAC address exists in the 85 * system. 86 * It would be nice to know if 'ifnet' or any of its sub-structures 87 * has been changed in any way. If not, we could simply skip the 88 * scan and safely return the MAC address we returned before. 89 */ 90 static void 91 uuid_node(uint16_t *node) 92 { 93 INIT_VNET_NET(curvnet); 94 struct ifnet *ifp; 95 struct ifaddr *ifa; 96 struct sockaddr_dl *sdl; 97 int i; 98 99 IFNET_RLOCK(); 100 TAILQ_FOREACH(ifp, &V_ifnet, if_link) { 101 /* Walk the address list */ 102 IF_ADDR_LOCK(ifp); 103 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 104 sdl = (struct sockaddr_dl*)ifa->ifa_addr; 105 if (sdl != NULL && sdl->sdl_family == AF_LINK && 106 sdl->sdl_type == IFT_ETHER) { 107 /* Got a MAC address. */ 108 bcopy(LLADDR(sdl), node, UUID_NODE_LEN); 109 IF_ADDR_UNLOCK(ifp); 110 IFNET_RUNLOCK(); 111 return; 112 } 113 } 114 IF_ADDR_UNLOCK(ifp); 115 } 116 IFNET_RUNLOCK(); 117 118 for (i = 0; i < (UUID_NODE_LEN>>1); i++) 119 node[i] = (uint16_t)arc4random(); 120 *((uint8_t*)node) |= 0x01; 121 } 122 123 /* 124 * Get the current time as a 60 bit count of 100-nanosecond intervals 125 * since 00:00:00.00, October 15,1582. We apply a magic offset to convert 126 * the Unix time since 00:00:00.00, January 1, 1970 to the date of the 127 * Gregorian reform to the Christian calendar. 128 */ 129 static uint64_t 130 uuid_time(void) 131 { 132 struct bintime bt; 133 uint64_t time = 0x01B21DD213814000LL; 134 135 bintime(&bt); 136 time += (uint64_t)bt.sec * 10000000LL; 137 time += (10000000LL * (uint32_t)(bt.frac >> 32)) >> 32; 138 return (time & ((1LL << 60) - 1LL)); 139 } 140 141 struct uuid * 142 kern_uuidgen(struct uuid *store, size_t count) 143 { 144 struct uuid_private uuid; 145 uint64_t time; 146 size_t n; 147 148 mtx_lock(&uuid_mutex); 149 150 uuid_node(uuid.node); 151 time = uuid_time(); 152 153 if (uuid_last.time.ll == 0LL || uuid_last.node[0] != uuid.node[0] || 154 uuid_last.node[1] != uuid.node[1] || 155 uuid_last.node[2] != uuid.node[2]) 156 uuid.seq = (uint16_t)arc4random() & 0x3fff; 157 else if (uuid_last.time.ll >= time) 158 uuid.seq = (uuid_last.seq + 1) & 0x3fff; 159 else 160 uuid.seq = uuid_last.seq; 161 162 uuid_last = uuid; 163 uuid_last.time.ll = (time + count - 1) & ((1LL << 60) - 1LL); 164 165 mtx_unlock(&uuid_mutex); 166 167 /* Set sequence and variant and deal with byte order. */ 168 uuid.seq = htobe16(uuid.seq | 0x8000); 169 170 for (n = 0; n < count; n++) { 171 /* Set time and version (=1). */ 172 uuid.time.x.low = (uint32_t)time; 173 uuid.time.x.mid = (uint16_t)(time >> 32); 174 uuid.time.x.hi = ((uint16_t)(time >> 48) & 0xfff) | (1 << 12); 175 store[n] = *(struct uuid *)&uuid; 176 time++; 177 } 178 179 return (store); 180 } 181 182 #ifndef _SYS_SYSPROTO_H_ 183 struct uuidgen_args { 184 struct uuid *store; 185 int count; 186 }; 187 #endif 188 int 189 uuidgen(struct thread *td, struct uuidgen_args *uap) 190 { 191 struct uuid *store; 192 size_t count; 193 int error; 194 195 /* 196 * Limit the number of UUIDs that can be created at the same time 197 * to some arbitrary number. This isn't really necessary, but I 198 * like to have some sort of upper-bound that's less than 2G :-) 199 * XXX probably needs to be tunable. 200 */ 201 if (uap->count < 1 || uap->count > 2048) 202 return (EINVAL); 203 204 count = uap->count; 205 store = malloc(count * sizeof(struct uuid), M_TEMP, M_WAITOK); 206 kern_uuidgen(store, count); 207 error = copyout(store, uap->store, count * sizeof(struct uuid)); 208 free(store, M_TEMP); 209 return (error); 210 } 211 212 int 213 snprintf_uuid(char *buf, size_t sz, struct uuid *uuid) 214 { 215 struct uuid_private *id; 216 int cnt; 217 218 id = (struct uuid_private *)uuid; 219 cnt = snprintf(buf, sz, "%08x-%04x-%04x-%04x-%04x%04x%04x", 220 id->time.x.low, id->time.x.mid, id->time.x.hi, be16toh(id->seq), 221 be16toh(id->node[0]), be16toh(id->node[1]), be16toh(id->node[2])); 222 return (cnt); 223 } 224 225 int 226 printf_uuid(struct uuid *uuid) 227 { 228 char buf[38]; 229 230 snprintf_uuid(buf, sizeof(buf), uuid); 231 return (printf("%s", buf)); 232 } 233 234 int 235 sbuf_printf_uuid(struct sbuf *sb, struct uuid *uuid) 236 { 237 char buf[38]; 238 239 snprintf_uuid(buf, sizeof(buf), uuid); 240 return (sbuf_printf(sb, "%s", buf)); 241 } 242 243 /* 244 * Encode/Decode UUID into byte-stream. 245 * http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt 246 * 247 * 0 1 2 3 248 * 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 1 249 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 250 * | time_low | 251 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 252 * | time_mid | time_hi_and_version | 253 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 254 * |clk_seq_hi_res | clk_seq_low | node (0-1) | 255 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 256 * | node (2-5) | 257 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 258 */ 259 260 void 261 le_uuid_enc(void *buf, struct uuid const *uuid) 262 { 263 u_char *p; 264 int i; 265 266 p = buf; 267 le32enc(p, uuid->time_low); 268 le16enc(p + 4, uuid->time_mid); 269 le16enc(p + 6, uuid->time_hi_and_version); 270 p[8] = uuid->clock_seq_hi_and_reserved; 271 p[9] = uuid->clock_seq_low; 272 for (i = 0; i < _UUID_NODE_LEN; i++) 273 p[10 + i] = uuid->node[i]; 274 } 275 276 void 277 le_uuid_dec(void const *buf, struct uuid *uuid) 278 { 279 u_char const *p; 280 int i; 281 282 p = buf; 283 uuid->time_low = le32dec(p); 284 uuid->time_mid = le16dec(p + 4); 285 uuid->time_hi_and_version = le16dec(p + 6); 286 uuid->clock_seq_hi_and_reserved = p[8]; 287 uuid->clock_seq_low = p[9]; 288 for (i = 0; i < _UUID_NODE_LEN; i++) 289 uuid->node[i] = p[10 + i]; 290 } 291 292 void 293 be_uuid_enc(void *buf, struct uuid const *uuid) 294 { 295 u_char *p; 296 int i; 297 298 p = buf; 299 be32enc(p, uuid->time_low); 300 be16enc(p + 4, uuid->time_mid); 301 be16enc(p + 6, uuid->time_hi_and_version); 302 p[8] = uuid->clock_seq_hi_and_reserved; 303 p[9] = uuid->clock_seq_low; 304 for (i = 0; i < _UUID_NODE_LEN; i++) 305 p[10 + i] = uuid->node[i]; 306 } 307 308 void 309 be_uuid_dec(void const *buf, struct uuid *uuid) 310 { 311 u_char const *p; 312 int i; 313 314 p = buf; 315 uuid->time_low = be32dec(p); 316 uuid->time_mid = le16dec(p + 4); 317 uuid->time_hi_and_version = be16dec(p + 6); 318 uuid->clock_seq_hi_and_reserved = p[8]; 319 uuid->clock_seq_low = p[9]; 320 for (i = 0; i < _UUID_NODE_LEN; i++) 321 uuid->node[i] = p[10 + i]; 322 } 323 324 int 325 parse_uuid(const char *str, struct uuid *uuid) 326 { 327 u_int c[11]; 328 int n; 329 330 /* An empty string represents a nil UUID. */ 331 if (*str == '\0') { 332 bzero(uuid, sizeof(*uuid)); 333 return (0); 334 } 335 336 /* The UUID string representation has a fixed length. */ 337 if (strlen(str) != 36) 338 return (EINVAL); 339 340 /* 341 * We only work with "new" UUIDs. New UUIDs have the form: 342 * 01234567-89ab-cdef-0123-456789abcdef 343 * The so called "old" UUIDs, which we don't support, have the form: 344 * 0123456789ab.cd.ef.01.23.45.67.89.ab 345 */ 346 if (str[8] != '-') 347 return (EINVAL); 348 349 n = sscanf(str, "%8x-%4x-%4x-%2x%2x-%2x%2x%2x%2x%2x%2x", c + 0, c + 1, 350 c + 2, c + 3, c + 4, c + 5, c + 6, c + 7, c + 8, c + 9, c + 10); 351 /* Make sure we have all conversions. */ 352 if (n != 11) 353 return (EINVAL); 354 355 /* Successful scan. Build the UUID. */ 356 uuid->time_low = c[0]; 357 uuid->time_mid = c[1]; 358 uuid->time_hi_and_version = c[2]; 359 uuid->clock_seq_hi_and_reserved = c[3]; 360 uuid->clock_seq_low = c[4]; 361 for (n = 0; n < 6; n++) 362 uuid->node[n] = c[n + 5]; 363 364 /* Check semantics... */ 365 return (((c[3] & 0x80) != 0x00 && /* variant 0? */ 366 (c[3] & 0xc0) != 0x80 && /* variant 1? */ 367 (c[3] & 0xe0) != 0xc0) ? EINVAL : 0); /* variant 2? */ 368 } 369