1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
|
/* $OpenBSD: ip_ipsp.c,v 1.21 1997/10/01 02:34:06 deraadt Exp $ */
/*
* The author of this code is John Ioannidis, ji@tla.org,
* (except when noted otherwise).
*
* This code was written for BSD/OS in Athens, Greece, in November 1995.
*
* Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
* by Angelos D. Keromytis, kermit@forthnet.gr.
*
* Copyright (C) 1995, 1996, 1997 by John Ioannidis and Angelos D. Keromytis.
*
* Permission to use, copy, and modify this software without fee
* is hereby granted, provided that this entire notice is included in
* all copies of any software which is or includes a copy or
* modification of this software.
*
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTY. IN PARTICULAR, NEITHER AUTHOR MAKES ANY
* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
* MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
* PURPOSE.
*/
/*
* IPSP Processing
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet/in_var.h>
#include <netinet/ip_var.h>
#include <netinet/ip_icmp.h>
#include <net/raw_cb.h>
#include <net/encap.h>
#include <netinet/ip_ipsp.h>
#include <netinet/ip_ah.h>
#include <netinet/ip_esp.h>
#include <dev/rndvar.h>
#include <sys/syslog.h>
int tdb_init __P((struct tdb *, struct mbuf *));
int ipsp_kern __P((int, char **, int));
int encdebug = 0;
u_int32_t kernfs_epoch = 0;
extern void encap_sendnotify(int, struct tdb *);
/*
* This is the proper place to define the various encapsulation transforms.
*/
struct xformsw xformsw[] = {
{ XF_IP4, 0, "IPv4 Simple Encapsulation",
ipe4_attach, ipe4_init, ipe4_zeroize,
(struct mbuf * (*)(struct mbuf *, struct tdb *))ipe4_input,
ipe4_output, },
{ XF_OLD_AH, XFT_AUTH, "Keyed Authentication, RFC 1828/1852",
ah_old_attach, ah_old_init, ah_old_zeroize,
ah_old_input, ah_old_output, },
{ XF_OLD_ESP, XFT_CONF, "Simple Encryption, RFC 1829/1851",
esp_old_attach, esp_old_init, esp_old_zeroize,
esp_old_input, esp_old_output, },
{ XF_NEW_AH, XFT_AUTH, "HMAC Authentication",
ah_new_attach, ah_new_init, ah_new_zeroize,
ah_new_input, ah_new_output, },
{ XF_NEW_ESP, XFT_CONF|XFT_AUTH,
"Encryption + Authentication + Replay Protection",
esp_new_attach, esp_new_init, esp_new_zeroize,
esp_new_input, esp_new_output, },
};
struct xformsw *xformswNXFORMSW = &xformsw[sizeof(xformsw)/sizeof(xformsw[0])];
unsigned char ipseczeroes[IPSEC_ZEROES_SIZE]; /* zeroes! */
/*
* Reserve an SPI; the SA is not valid yet though. Zero is reserved as
* an error return value. If tspi is not zero, we try to allocate that
* SPI. SPIs less than 255 are reserved, so we check for those too.
*/
u_int32_t
reserve_spi(u_int32_t tspi, struct in_addr src, u_int8_t proto, int *errval)
{
struct tdb *tdbp;
u_int32_t spi = tspi; /* Don't change */
while (1)
{
while (spi <= 255) /* Get a new SPI */
get_random_bytes((void *) &spi, sizeof(spi));
/* Check whether we're using this SPI already */
if (gettdb(spi, src, proto) != (struct tdb *) NULL)
{
if (tspi != 0) /* If one was proposed, report error */
{
(*errval) = EEXIST;
return 0;
}
spi = 0;
continue;
}
MALLOC(tdbp, struct tdb *, sizeof(*tdbp), M_TDB, M_WAITOK);
if (tdbp == NULL)
{
(*errval) = ENOBUFS;
return 0;
}
bzero((caddr_t) tdbp, sizeof(*tdbp));
tdbp->tdb_spi = spi;
tdbp->tdb_dst = src;
tdbp->tdb_sproto = proto;
tdbp->tdb_flags |= TDBF_INVALID;
tdbp->tdb_epoch = kernfs_epoch - 1;
puttdb(tdbp);
return spi;
}
}
/*
* An IPSP SAID is really the concatenation of the SPI found in the
* packet, the destination address of the packet and the IPsec protocol.
* When we receive an IPSP packet, we need to look up its tunnel descriptor
* block, based on the SPI in the packet and the destination address (which
* is really one of our addresses if we received the packet!
*/
struct tdb *
gettdb(u_int32_t spi, struct in_addr dst, u_int8_t proto)
{
int hashval;
struct tdb *tdbp;
hashval = (spi + dst.s_addr + proto) % TDB_HASHMOD;
for (tdbp = tdbh[hashval]; tdbp; tdbp = tdbp->tdb_hnext)
if ((tdbp->tdb_spi == spi) && (tdbp->tdb_dst.s_addr == dst.s_addr)
&& (tdbp->tdb_sproto == proto))
break;
return tdbp;
}
struct flow *
get_flow(void)
{
struct flow *flow;
MALLOC(flow, struct flow *, sizeof(struct flow), M_TDB, M_WAITOK);
if (flow == (struct flow *) NULL)
return (struct flow *) NULL;
bzero(flow, sizeof(struct flow));
return flow;
}
struct expiration *
get_expiration(void)
{
struct expiration *exp;
MALLOC(exp, struct expiration *, sizeof(struct expiration), M_TDB,
M_WAITOK);
if (exp == (struct expiration *) NULL)
return (struct expiration *) NULL;
bzero(exp, sizeof(struct expiration));
return exp;
}
void
cleanup_expirations(struct in_addr dst, u_int32_t spi, u_int8_t sproto)
{
struct expiration *exp, *nexp;
for (exp = explist; exp; exp = exp->exp_next)
if ((exp->exp_dst.s_addr == dst.s_addr) &&
(exp->exp_spi == spi) && (exp->exp_sproto == sproto))
{
/* Link previous to next */
if (exp->exp_prev == (struct expiration *) NULL)
explist = exp->exp_next;
else
exp->exp_prev->exp_next = exp->exp_next;
/* Link next (if it exists) to previous */
if (exp->exp_next != (struct expiration *) NULL)
exp->exp_next->exp_prev = exp->exp_prev;
nexp = exp;
exp = exp->exp_prev;
free(nexp, M_TDB);
}
}
void
handle_expirations(void *arg)
{
struct expiration *exp;
struct tdb *tdb;
if (explist == (struct expiration *) NULL)
return;
while (1)
{
exp = explist;
if (exp == (struct expiration *) NULL)
return;
else
if (exp->exp_timeout > time.tv_sec)
break;
/* Advance pointer */
explist = explist->exp_next;
if (explist)
explist->exp_prev = NULL;
tdb = gettdb(exp->exp_spi, exp->exp_dst, exp->exp_sproto);
if (tdb == (struct tdb *) NULL)
{
free(exp, M_TDB);
continue; /* TDB is gone, ignore this */
}
/* Soft expirations */
if (tdb->tdb_flags & TDBF_SOFT_TIMER)
if (tdb->tdb_soft_timeout <= time.tv_sec)
{
encap_sendnotify(NOTIFY_SOFT_EXPIRE, tdb);
tdb->tdb_flags &= ~TDBF_SOFT_TIMER;
}
else
if (tdb->tdb_flags & TDBF_SOFT_FIRSTUSE)
if (tdb->tdb_first_use + tdb->tdb_soft_first_use <=
time.tv_sec)
{
encap_sendnotify(NOTIFY_SOFT_EXPIRE, tdb);
tdb->tdb_flags &= ~TDBF_SOFT_FIRSTUSE;
}
/* Hard expirations */
if (tdb->tdb_flags & TDBF_TIMER)
if (tdb->tdb_exp_timeout <= time.tv_sec)
{
encap_sendnotify(NOTIFY_HARD_EXPIRE, tdb);
tdb_delete(tdb, 0);
}
else
if (tdb->tdb_flags & TDBF_FIRSTUSE)
if (tdb->tdb_first_use + tdb->tdb_exp_first_use <=
time.tv_sec)
{
encap_sendnotify(NOTIFY_HARD_EXPIRE, tdb);
tdb_delete(tdb, 0);
}
free(exp, M_TDB);
}
if (explist)
timeout(handle_expirations, (void *) NULL,
hz * (explist->exp_timeout - time.tv_sec));
}
void
put_expiration(struct expiration *exp)
{
struct expiration *expt;
int reschedflag = 0;
if (exp == (struct expiration *) NULL)
{
#ifdef ENCDEBUG
if (encdebug)
log(LOG_WARNING, "put_expiration(): NULL argument\n");
#endif /* ENCDEBUG */
return;
}
if (explist == (struct expiration *) NULL)
{
explist = exp;
reschedflag = 1;
}
else
if (explist->exp_timeout > exp->exp_timeout)
{
exp->exp_next = explist;
explist->exp_prev = exp;
explist = exp;
reschedflag = 2;
}
else
{
for (expt = explist; expt->exp_next; expt = expt->exp_next)
if (expt->exp_next->exp_timeout > exp->exp_timeout)
{
expt->exp_next->exp_prev = exp;
exp->exp_next = expt->exp_next;
expt->exp_next = exp;
exp->exp_prev = expt;
break;
}
if (expt->exp_next == (struct expiration *) NULL)
{
expt->exp_next = exp;
exp->exp_prev = expt;
}
}
switch (reschedflag)
{
case 1:
timeout(handle_expirations, (void *) NULL,
hz * (explist->exp_timeout - time.tv_sec));
break;
case 2:
untimeout(handle_expirations, (void *) NULL);
timeout(handle_expirations, (void *) NULL,
hz * (explist->exp_timeout - time.tv_sec));
break;
default:
break;
}
}
struct flow *
find_flow(struct in_addr src, struct in_addr srcmask, struct in_addr dst,
struct in_addr dstmask, u_int8_t proto, u_int16_t sport,
u_int16_t dport, struct tdb *tdb)
{
struct flow *flow;
for (flow = tdb->tdb_flow; flow; flow = flow->flow_next)
if ((src.s_addr == flow->flow_src.s_addr) &&
(dst.s_addr == flow->flow_dst.s_addr) &&
(srcmask.s_addr == flow->flow_srcmask.s_addr) &&
(dstmask.s_addr == flow->flow_dstmask.s_addr) &&
(proto == flow->flow_proto) &&
(sport == flow->flow_sport) && (dport == flow->flow_dport))
return flow;
return (struct flow *) NULL;
}
struct flow *
find_global_flow(struct in_addr src, struct in_addr srcmask,
struct in_addr dst, struct in_addr dstmask,
u_int8_t proto, u_int16_t sport, u_int16_t dport)
{
struct flow *flow;
struct tdb *tdb;
int i;
for (i = 0; i < TDB_HASHMOD; i++)
for (tdb = tdbh[i]; tdb; tdb = tdb->tdb_hnext)
if ((flow = find_flow(src, srcmask, dst, dstmask, proto, sport,
dport, tdb)) != (struct flow *) NULL)
return flow;
return (struct flow *) NULL;
}
void
puttdb(struct tdb *tdbp)
{
int hashval;
hashval = ((tdbp->tdb_sproto + tdbp->tdb_spi + tdbp->tdb_dst.s_addr)
% TDB_HASHMOD);
tdbp->tdb_hnext = tdbh[hashval];
tdbh[hashval] = tdbp;
}
void
put_flow(struct flow *flow, struct tdb *tdb)
{
flow->flow_next = tdb->tdb_flow;
flow->flow_prev = (struct flow *) NULL;
tdb->tdb_flow = flow;
flow->flow_sa = tdb;
if (flow->flow_next)
flow->flow_next->flow_prev = flow;
}
void
delete_flow(struct flow *flow, struct tdb *tdb)
{
if (tdb->tdb_flow == flow)
{
tdb->tdb_flow = flow->flow_next;
if (tdb->tdb_flow)
tdb->tdb_flow->flow_prev = (struct flow *) NULL;
}
else
{
flow->flow_prev->flow_next = flow->flow_next;
if (flow->flow_next)
flow->flow_next->flow_prev = flow->flow_prev;
}
FREE(flow, M_TDB);
}
int
tdb_delete(struct tdb *tdbp, int delchain)
{
struct tdb *tdbpp;
struct flow *flow;
int hashval;
hashval = ((tdbp->tdb_sproto + tdbp->tdb_spi + tdbp->tdb_dst.s_addr)
% TDB_HASHMOD);
if (tdbh[hashval] == tdbp)
{
tdbpp = tdbp;
tdbh[hashval] = tdbp->tdb_hnext;
}
else
for (tdbpp = tdbh[hashval]; tdbpp != NULL; tdbpp = tdbpp->tdb_hnext)
if (tdbpp->tdb_hnext == tdbp)
{
tdbpp->tdb_hnext = tdbp->tdb_hnext;
tdbpp = tdbp;
}
if (tdbp != tdbpp)
return EINVAL; /* Should never happen */
/* If there was something before us in the chain, make it point nowhere */
if (tdbp->tdb_inext)
tdbp->tdb_inext->tdb_onext = NULL;
tdbpp = tdbp->tdb_onext;
if (tdbp->tdb_xform)
(*(tdbp->tdb_xform->xf_zeroize))(tdbp);
for (flow = tdbp->tdb_flow; flow; flow = tdbp->tdb_flow)
delete_flow(flow, tdbp);
cleanup_expirations(tdbp->tdb_dst, tdbp->tdb_spi, tdbp->tdb_sproto);
FREE(tdbp, M_TDB);
if (delchain && tdbpp)
return tdb_delete(tdbpp, delchain);
else
return 0;
}
int
tdb_init(struct tdb *tdbp, struct mbuf *m)
{
int alg;
struct encap_msghdr *em;
struct xformsw *xsp;
em = mtod(m, struct encap_msghdr *);
alg = em->em_alg;
/* Record establishment time */
tdbp->tdb_established = time.tv_sec;
tdbp->tdb_epoch = kernfs_epoch - 1;
for (xsp = xformsw; xsp < xformswNXFORMSW; xsp++)
if (xsp->xf_type == alg)
return (*(xsp->xf_init))(tdbp, xsp, m);
log(LOG_ERR, "tdb_init(): no alg %d for spi %08x, addr %x, proto %d\n",
alg, ntohl(tdbp->tdb_spi), tdbp->tdb_dst.s_addr, tdbp->tdb_sproto);
return EINVAL;
}
/*
* Used by kernfs
*/
int
ipsp_kern(int off, char **bufp, int len)
{
static char buffer[IPSEC_KERNFS_BUFSIZE];
struct tdb *tdb;
struct flow *fl;
int l, i;
if (off == 0)
kernfs_epoch++;
if (bufp == NULL)
return 0;
bzero(buffer, IPSEC_KERNFS_BUFSIZE);
*bufp = buffer;
for (i = 0; i < TDB_HASHMOD; i++)
for (tdb = tdbh[i]; tdb; tdb = tdb->tdb_hnext)
if (tdb->tdb_epoch != kernfs_epoch)
{
tdb->tdb_epoch = kernfs_epoch;
l = sprintf(buffer, "SPI = %08x, Destination = %s, Sproto = %u\n",
ntohl(tdb->tdb_spi), inet_ntoa(tdb->tdb_dst),
tdb->tdb_sproto);
l += sprintf(buffer + l, "\testablished %d seconds ago\n",
time.tv_sec - tdb->tdb_established);
l += sprintf(buffer + l, "\tsrc = %s, flags = %08x, SAtype = %u\n",
inet_ntoa(tdb->tdb_src), tdb->tdb_flags,
tdb->tdb_satype);
if (tdb->tdb_xform)
l += sprintf(buffer + l, "\txform = <%s>\n",
tdb->tdb_xform->xf_name);
else
l += sprintf(buffer + l, "\txform = <(null)>\n");
l += sprintf(buffer + l, "\tOSrc = %s", inet_ntoa(tdb->tdb_osrc));
l += sprintf(buffer + l, " ODst = %s, TTL = %u\n",
inet_ntoa(tdb->tdb_odst), tdb->tdb_ttl);
if (tdb->tdb_onext)
l += sprintf(buffer + l, "\tNext (on output) SA: SPI = %08x, Destination = %s, Sproto = %u\n", tdb->tdb_onext->tdb_spi, inet_ntoa(tdb->tdb_onext->tdb_dst), tdb->tdb_onext->tdb_sproto);
if (tdb->tdb_inext)
l += sprintf(buffer + l, "\tNext (on input) SA: SPI = %08x, Destination = %s, Sproto = %u\n", tdb->tdb_inext->tdb_spi, inet_ntoa(tdb->tdb_inext->tdb_dst), tdb->tdb_inext->tdb_sproto);
/* XXX We can reuse variable i, we're not going to loop again */
for (i = 0, fl = tdb->tdb_flow; fl; fl = fl->flow_next)
i++;
l += sprintf(buffer + l, "\t%u flows counted (use netstat -r for more information)\n", i);
l += sprintf(buffer + l, "\tExpirations:\n");
if (tdb->tdb_flags & TDBF_TIMER)
l += sprintf(buffer + l, "\t\tHard expiration(1) in %u seconds\n",
tdb->tdb_exp_timeout - time.tv_sec);
if (tdb->tdb_flags & TDBF_SOFT_TIMER)
l += sprintf(buffer + l, "\t\tSoft expiration(1) in %u seconds\n",
tdb->tdb_soft_timeout - time.tv_sec);
if (tdb->tdb_flags & TDBF_BYTES)
l += sprintf(buffer + l, "\t\tHard expiration after %qu bytes\n",
tdb->tdb_exp_bytes);
if (tdb->tdb_flags & TDBF_SOFT_BYTES)
l += sprintf(buffer + l, "\t\tSoft expiration after %qu bytes\n",
tdb->tdb_soft_bytes);
l += sprintf(buffer + l, "\t\tCurrently %qu bytes processed\n",
tdb->tdb_cur_bytes);
if (tdb->tdb_flags & TDBF_PACKETS)
l += sprintf(buffer + l,
"\t\tHard expiration after %qu packets\n",
tdb->tdb_exp_packets);
if (tdb->tdb_flags & TDBF_SOFT_PACKETS)
l += sprintf(buffer + l,
"\t\tSoft expiration after %qu packets\n",
tdb->tdb_soft_packets);
l += sprintf(buffer + l, "\t\tCurrently %qu packets processed\n",
tdb->tdb_cur_packets);
if (tdb->tdb_flags & TDBF_FIRSTUSE)
l += sprintf(buffer + l, "\t\tHard expiration(2) in %u seconds\n",
(tdb->tdb_established + tdb->tdb_exp_first_use) -
time.tv_sec);
if (tdb->tdb_flags & TDBF_SOFT_FIRSTUSE)
l += sprintf(buffer + l, "\t\tSoft expiration(2) in %u seconds\n",
(tdb->tdb_established + tdb->tdb_soft_first_use) -
time.tv_sec);
if (!(tdb->tdb_flags & (TDBF_TIMER | TDBF_SOFT_TIMER | TDBF_BYTES |
TDBF_SOFT_PACKETS | TDBF_PACKETS |
TDBF_SOFT_BYTES | TDBF_FIRSTUSE |
TDBF_SOFT_FIRSTUSE)))
l += sprintf(buffer + l, "\t\t(none)\n");
l += sprintf(buffer + l, "\n");
return l;
}
return 0;
}
|