FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_uuid.c
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: releng/10.4/sys/kern/kern_uuid.c 262239 2014-02-20 08:55:59Z brueffer $");
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
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 struct 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
82 static struct uuid_private uuid_last;
83
84 #define UUID_NETHER 4
85 static struct uuid_macaddr uuid_ether[UUID_NETHER];
86
87 static struct mtx uuid_mutex;
88 MTX_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 */
96 static void
97 uuid_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 */
117 static uint64_t
118 uuid_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
129 struct uuid *
130 kern_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_
171 struct uuidgen_args {
172 struct uuid *store;
173 int count;
174 };
175 #endif
176 int
177 sys_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
200 int
201 uuid_ether_add(const uint8_t *addr)
202 {
203 int i, sum;
204
205 /*
206 * Validate input. No multicast (flag 0x1), no locally administered
207 * (flag 0x2) and no 'all-zeroes' addresses.
208 */
209 if (addr[0] & 0x03)
210 return (EINVAL);
211 sum = 0;
212 for (i = 0; i < UUID_NODE_LEN; i++)
213 sum += addr[i];
214 if (sum == 0)
215 return (EINVAL);
216
217 mtx_lock(&uuid_mutex);
218
219 /* Make sure the MAC isn't known already and that there's space. */
220 i = 0;
221 while (i < UUID_NETHER && uuid_ether[i].state == UUID_ETHER_UNIQUE) {
222 if (!bcmp(addr, uuid_ether[i].node, UUID_NODE_LEN)) {
223 mtx_unlock(&uuid_mutex);
224 return (EEXIST);
225 }
226 i++;
227 }
228 if (i == UUID_NETHER) {
229 mtx_unlock(&uuid_mutex);
230 return (ENOSPC);
231 }
232
233 /* Insert MAC at index, moving the non-empty entry if possible. */
234 if (uuid_ether[i].state == UUID_ETHER_RANDOM && i < UUID_NETHER - 1)
235 uuid_ether[i + 1] = uuid_ether[i];
236 uuid_ether[i].state = UUID_ETHER_UNIQUE;
237 bcopy(addr, uuid_ether[i].node, UUID_NODE_LEN);
238 mtx_unlock(&uuid_mutex);
239 return (0);
240 }
241
242 int
243 uuid_ether_del(const uint8_t *addr)
244 {
245 int i;
246
247 mtx_lock(&uuid_mutex);
248 i = 0;
249 while (i < UUID_NETHER && uuid_ether[i].state == UUID_ETHER_UNIQUE &&
250 bcmp(addr, uuid_ether[i].node, UUID_NODE_LEN))
251 i++;
252 if (i == UUID_NETHER || uuid_ether[i].state != UUID_ETHER_UNIQUE) {
253 mtx_unlock(&uuid_mutex);
254 return (ENOENT);
255 }
256
257 /* Remove it by shifting higher index entries down. */
258 while (i < UUID_NETHER - 1 && uuid_ether[i].state != UUID_ETHER_EMPTY) {
259 uuid_ether[i] = uuid_ether[i + 1];
260 i++;
261 }
262 if (uuid_ether[i].state != UUID_ETHER_EMPTY) {
263 uuid_ether[i].state = UUID_ETHER_EMPTY;
264 bzero(uuid_ether[i].node, UUID_NODE_LEN);
265 }
266 mtx_unlock(&uuid_mutex);
267 return (0);
268 }
269
270 int
271 snprintf_uuid(char *buf, size_t sz, struct uuid *uuid)
272 {
273 struct uuid_private *id;
274 int cnt;
275
276 id = (struct uuid_private *)uuid;
277 cnt = snprintf(buf, sz, "%08x-%04x-%04x-%04x-%04x%04x%04x",
278 id->time.x.low, id->time.x.mid, id->time.x.hi, be16toh(id->seq),
279 be16toh(id->node[0]), be16toh(id->node[1]), be16toh(id->node[2]));
280 return (cnt);
281 }
282
283 int
284 printf_uuid(struct uuid *uuid)
285 {
286 char buf[38];
287
288 snprintf_uuid(buf, sizeof(buf), uuid);
289 return (printf("%s", buf));
290 }
291
292 int
293 sbuf_printf_uuid(struct sbuf *sb, struct uuid *uuid)
294 {
295 char buf[38];
296
297 snprintf_uuid(buf, sizeof(buf), uuid);
298 return (sbuf_printf(sb, "%s", buf));
299 }
300
301 /*
302 * Encode/Decode UUID into byte-stream.
303 * http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt
304 *
305 * 0 1 2 3
306 * 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
307 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
308 * | time_low |
309 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
310 * | time_mid | time_hi_and_version |
311 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
312 * |clk_seq_hi_res | clk_seq_low | node (0-1) |
313 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
314 * | node (2-5) |
315 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
316 */
317
318 void
319 le_uuid_enc(void *buf, struct uuid const *uuid)
320 {
321 u_char *p;
322 int i;
323
324 p = buf;
325 le32enc(p, uuid->time_low);
326 le16enc(p + 4, uuid->time_mid);
327 le16enc(p + 6, uuid->time_hi_and_version);
328 p[8] = uuid->clock_seq_hi_and_reserved;
329 p[9] = uuid->clock_seq_low;
330 for (i = 0; i < _UUID_NODE_LEN; i++)
331 p[10 + i] = uuid->node[i];
332 }
333
334 void
335 le_uuid_dec(void const *buf, struct uuid *uuid)
336 {
337 u_char const *p;
338 int i;
339
340 p = buf;
341 uuid->time_low = le32dec(p);
342 uuid->time_mid = le16dec(p + 4);
343 uuid->time_hi_and_version = le16dec(p + 6);
344 uuid->clock_seq_hi_and_reserved = p[8];
345 uuid->clock_seq_low = p[9];
346 for (i = 0; i < _UUID_NODE_LEN; i++)
347 uuid->node[i] = p[10 + i];
348 }
349
350 void
351 be_uuid_enc(void *buf, struct uuid const *uuid)
352 {
353 u_char *p;
354 int i;
355
356 p = buf;
357 be32enc(p, uuid->time_low);
358 be16enc(p + 4, uuid->time_mid);
359 be16enc(p + 6, uuid->time_hi_and_version);
360 p[8] = uuid->clock_seq_hi_and_reserved;
361 p[9] = uuid->clock_seq_low;
362 for (i = 0; i < _UUID_NODE_LEN; i++)
363 p[10 + i] = uuid->node[i];
364 }
365
366 void
367 be_uuid_dec(void const *buf, struct uuid *uuid)
368 {
369 u_char const *p;
370 int i;
371
372 p = buf;
373 uuid->time_low = be32dec(p);
374 uuid->time_mid = be16dec(p + 4);
375 uuid->time_hi_and_version = be16dec(p + 6);
376 uuid->clock_seq_hi_and_reserved = p[8];
377 uuid->clock_seq_low = p[9];
378 for (i = 0; i < _UUID_NODE_LEN; i++)
379 uuid->node[i] = p[10 + i];
380 }
381
382 int
383 parse_uuid(const char *str, struct uuid *uuid)
384 {
385 u_int c[11];
386 int n;
387
388 /* An empty string represents a nil UUID. */
389 if (*str == '\0') {
390 bzero(uuid, sizeof(*uuid));
391 return (0);
392 }
393
394 /* The UUID string representation has a fixed length. */
395 if (strlen(str) != 36)
396 return (EINVAL);
397
398 /*
399 * We only work with "new" UUIDs. New UUIDs have the form:
400 * 01234567-89ab-cdef-0123-456789abcdef
401 * The so called "old" UUIDs, which we don't support, have the form:
402 * 0123456789ab.cd.ef.01.23.45.67.89.ab
403 */
404 if (str[8] != '-')
405 return (EINVAL);
406
407 n = sscanf(str, "%8x-%4x-%4x-%2x%2x-%2x%2x%2x%2x%2x%2x", c + 0, c + 1,
408 c + 2, c + 3, c + 4, c + 5, c + 6, c + 7, c + 8, c + 9, c + 10);
409 /* Make sure we have all conversions. */
410 if (n != 11)
411 return (EINVAL);
412
413 /* Successful scan. Build the UUID. */
414 uuid->time_low = c[0];
415 uuid->time_mid = c[1];
416 uuid->time_hi_and_version = c[2];
417 uuid->clock_seq_hi_and_reserved = c[3];
418 uuid->clock_seq_low = c[4];
419 for (n = 0; n < 6; n++)
420 uuid->node[n] = c[n + 5];
421
422 /* Check semantics... */
423 return (((c[3] & 0x80) != 0x00 && /* variant 0? */
424 (c[3] & 0xc0) != 0x80 && /* variant 1? */
425 (c[3] & 0xe0) != 0xc0) ? EINVAL : 0); /* variant 2? */
426 }
Cache object: 2c9be32efe4063edd1bc6db43f07f6ba
|