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