1 /*
2 * Copyright (C) 1995-2003 by Darren Reed.
3 *
4 * See the IPFILTER.LICENCE file for details on licencing.
5 *
6 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
7 *
8 * Copyright (c) 2014, Joyent, Inc. All rights reserved.
9 */
10
11 #if defined(KERNEL) || defined(_KERNEL)
12 # undef KERNEL
13 # undef _KERNEL
14 # define KERNEL 1
15 # define _KERNEL 1
16 #endif
17 #include <sys/errno.h>
18 #include <sys/types.h>
19 #include <sys/param.h>
20 #include <sys/file.h>
21 #if defined(__NetBSD__) && (NetBSD >= 199905) && !defined(IPFILTER_LKM) && \
22 defined(_KERNEL)
23 # include "opt_ipfilter_log.h"
24 #endif
25 #if defined(_KERNEL) && defined(__FreeBSD_version) && \
26 (__FreeBSD_version >= 400000) && !defined(KLD_MODULE)
27 #include "opt_inet6.h"
28 #endif
29 #if !defined(_KERNEL) && !defined(__KERNEL__)
30 # include <stdio.h>
31 # include <stdlib.h>
32 # include <string.h>
33 # define _KERNEL
34 # ifdef __OpenBSD__
35 struct file;
36 # endif
37 # include <sys/uio.h>
38 # undef _KERNEL
39 #endif
40 #if defined(_KERNEL) && (__FreeBSD_version >= 220000)
41 # include <sys/filio.h>
42 # include <sys/fcntl.h>
43 # if (__FreeBSD_version >= 300000) && !defined(IPFILTER_LKM)
44 # include "opt_ipfilter.h"
45 # endif
46 #else
47 # include <sys/ioctl.h>
48 #endif
49 #include <sys/time.h>
50 #if !defined(linux)
51 # include <sys/protosw.h>
52 #endif
53 #include <sys/socket.h>
54 #if defined(_KERNEL)
55 # include <sys/systm.h>
56 # if !defined(__SVR4) && !defined(__svr4__)
57 # include <sys/mbuf.h>
58 # endif
59 #endif
60 #if defined(__SVR4) || defined(__svr4__)
61 # include <sys/filio.h>
62 # include <sys/byteorder.h>
63 # ifdef _KERNEL
64 # include <sys/dditypes.h>
65 # endif
66 # include <sys/stream.h>
67 # include <sys/kmem.h>
68 #endif
69
70 #include <net/if.h>
71 #ifdef sun
72 # include <net/af.h>
73 #endif
74 #include <net/route.h>
75 #include <netinet/in.h>
76 #include <netinet/in_systm.h>
77 #include <netinet/ip.h>
78 #include <netinet/tcp.h>
79 #if !defined(linux)
80 # include <netinet/ip_var.h>
81 #endif
82 #if !defined(__hpux) && !defined(linux)
83 # include <netinet/tcp_fsm.h>
84 #endif
85 #include <netinet/udp.h>
86 #include <netinet/ip_icmp.h>
87 #include "netinet/ip_compat.h"
88 #include <netinet/tcpip.h>
89 #include "netinet/ip_fil.h"
90 #include "netinet/ip_nat.h"
91 #include "netinet/ip_frag.h"
92 #include "netinet/ip_state.h"
93 #include "netinet/ip_proxy.h"
94 #include "netinet/ipf_stack.h"
95 #ifdef IPFILTER_SYNC
96 #include "netinet/ip_sync.h"
97 #endif
98 #ifdef IPFILTER_SCAN
99 #include "netinet/ip_scan.h"
100 #endif
101 #ifdef USE_INET6
102 #include <netinet/icmp6.h>
103 #endif
104 #if (__FreeBSD_version >= 300000)
105 # include <sys/malloc.h>
106 # if defined(_KERNEL) && !defined(IPFILTER_LKM)
107 # include <sys/libkern.h>
108 # include <sys/systm.h>
109 # endif
110 #endif
111 /* END OF INCLUDES */
112
113
114 #if !defined(lint)
115 static const char sccsid[] = "@(#)ip_state.c 1.8 6/5/96 (C) 1993-2000 Darren Reed";
116 static const char rcsid[] = "@(#)$Id: ip_state.c,v 2.186.2.36 2005/08/11 19:58:03 darrenr Exp $";
117 #endif
118
119 #ifdef USE_INET6
120 static ipstate_t *fr_checkicmp6matchingstate __P((fr_info_t *));
121 #endif
122 static ipstate_t *fr_matchsrcdst __P((fr_info_t *, ipstate_t *, i6addr_t *,
123 i6addr_t *, tcphdr_t *, u_32_t));
124 static ipstate_t *fr_checkicmpmatchingstate __P((fr_info_t *));
125 static int fr_state_flush __P((int, int, ipf_stack_t *));
126 static ips_stat_t *fr_statetstats __P((ipf_stack_t *));
127 static int fr_state_remove __P((caddr_t, ipf_stack_t *));
128 static void fr_ipsmove __P((ipstate_t *, u_int, ipf_stack_t *));
129 static int fr_tcpstate __P((fr_info_t *, tcphdr_t *, ipstate_t *));
130 static int fr_tcpoptions __P((fr_info_t *, tcphdr_t *, tcpdata_t *));
131 static ipstate_t *fr_stclone __P((fr_info_t *, tcphdr_t *, ipstate_t *));
132 static void fr_fixinisn __P((fr_info_t *, ipstate_t *));
133 static void fr_fixoutisn __P((fr_info_t *, ipstate_t *));
134 static void fr_checknewisn __P((fr_info_t *, ipstate_t *));
135 static int fr_stateiter __P((ipftoken_t *, ipfgeniter_t *, ipf_stack_t *));
136
137 int fr_stputent __P((caddr_t, ipf_stack_t *));
138 int fr_stgetent __P((caddr_t, ipf_stack_t *));
139
140 #define ONE_DAY IPF_TTLVAL(1 * 86400) /* 1 day */
141 #define FIVE_DAYS (5 * ONE_DAY)
142 #define DOUBLE_HASH(x, ifs) \
143 (((x) + ifs->ifs_ips_seed[(x) % ifs->ifs_fr_statesize]) % ifs->ifs_fr_statesize)
144
145
146 /* ------------------------------------------------------------------------ */
147 /* Function: fr_stateinit */
148 /* Returns: int - 0 == success, -1 == failure */
149 /* Parameters: ifs - ipf stack instance */
150 /* */
151 /* Initialise all the global variables used within the state code. */
152 /* This action also includes initiailising locks. */
153 /* ------------------------------------------------------------------------ */
154 int fr_stateinit(ifs)
155 ipf_stack_t *ifs;
156 {
157 #if defined(NEED_LOCAL_RAND) || !defined(_KERNEL)
158 struct timeval tv;
159 #endif
160 int i;
161
162 KMALLOCS(ifs->ifs_ips_table, ipstate_t **,
163 ifs->ifs_fr_statesize * sizeof(ipstate_t *));
164 if (ifs->ifs_ips_table == NULL)
165 return -1;
166 bzero((char *)ifs->ifs_ips_table,
167 ifs->ifs_fr_statesize * sizeof(ipstate_t *));
168
169 KMALLOCS(ifs->ifs_ips_seed, u_long *,
170 ifs->ifs_fr_statesize * sizeof(*ifs->ifs_ips_seed));
171 if (ifs->ifs_ips_seed == NULL)
172 return -2;
173 #if defined(NEED_LOCAL_RAND) || !defined(_KERNEL)
174 tv.tv_sec = 0;
175 GETKTIME(&tv);
176 #endif
177 for (i = 0; i < ifs->ifs_fr_statesize; i++) {
178 /*
179 * XXX - ips_seed[X] should be a random number of sorts.
180 */
181 #if !defined(NEED_LOCAL_RAND) && defined(_KERNEL)
182 ifs->ifs_ips_seed[i] = ipf_random();
183 #else
184 ifs->ifs_ips_seed[i] = ((u_long)ifs->ifs_ips_seed + i) *
185 ifs->ifs_fr_statesize;
186 ifs->ifs_ips_seed[i] += tv.tv_sec;
187 ifs->ifs_ips_seed[i] *= (u_long)ifs->ifs_ips_seed;
188 ifs->ifs_ips_seed[i] ^= 0x5a5aa5a5;
189 ifs->ifs_ips_seed[i] *= ifs->ifs_fr_statemax;
190 #endif
191 }
192
193 /* fill icmp reply type table */
194 for (i = 0; i <= ICMP_MAXTYPE; i++)
195 icmpreplytype4[i] = -1;
196 icmpreplytype4[ICMP_ECHO] = ICMP_ECHOREPLY;
197 icmpreplytype4[ICMP_TSTAMP] = ICMP_TSTAMPREPLY;
198 icmpreplytype4[ICMP_IREQ] = ICMP_IREQREPLY;
199 icmpreplytype4[ICMP_MASKREQ] = ICMP_MASKREPLY;
200 #ifdef USE_INET6
201 /* fill icmp reply type table */
202 for (i = 0; i <= ICMP6_MAXTYPE; i++)
203 icmpreplytype6[i] = -1;
204 icmpreplytype6[ICMP6_ECHO_REQUEST] = ICMP6_ECHO_REPLY;
205 icmpreplytype6[ICMP6_MEMBERSHIP_QUERY] = ICMP6_MEMBERSHIP_REPORT;
206 icmpreplytype6[ICMP6_NI_QUERY] = ICMP6_NI_REPLY;
207 icmpreplytype6[ND_ROUTER_SOLICIT] = ND_ROUTER_ADVERT;
208 icmpreplytype6[ND_NEIGHBOR_SOLICIT] = ND_NEIGHBOR_ADVERT;
209 #endif
210
211 KMALLOCS(ifs->ifs_ips_stats.iss_bucketlen, u_long *,
212 ifs->ifs_fr_statesize * sizeof(u_long));
213 if (ifs->ifs_ips_stats.iss_bucketlen == NULL)
214 return -1;
215 bzero((char *)ifs->ifs_ips_stats.iss_bucketlen,
216 ifs->ifs_fr_statesize * sizeof(u_long));
217
218 if (ifs->ifs_fr_state_maxbucket == 0) {
219 for (i = ifs->ifs_fr_statesize; i > 0; i >>= 1)
220 ifs->ifs_fr_state_maxbucket++;
221 ifs->ifs_fr_state_maxbucket *= 2;
222 }
223
224 fr_sttab_init(ifs->ifs_ips_tqtqb, ifs);
225 ifs->ifs_ips_tqtqb[IPF_TCP_NSTATES - 1].ifq_next = &ifs->ifs_ips_udptq;
226 ifs->ifs_ips_udptq.ifq_ttl = (u_long)ifs->ifs_fr_udptimeout;
227 ifs->ifs_ips_udptq.ifq_ref = 1;
228 ifs->ifs_ips_udptq.ifq_head = NULL;
229 ifs->ifs_ips_udptq.ifq_tail = &ifs->ifs_ips_udptq.ifq_head;
230 MUTEX_INIT(&ifs->ifs_ips_udptq.ifq_lock, "ipftq udp tab");
231 ifs->ifs_ips_udptq.ifq_next = &ifs->ifs_ips_udpacktq;
232 ifs->ifs_ips_udpacktq.ifq_ttl = (u_long)ifs->ifs_fr_udpacktimeout;
233 ifs->ifs_ips_udpacktq.ifq_ref = 1;
234 ifs->ifs_ips_udpacktq.ifq_head = NULL;
235 ifs->ifs_ips_udpacktq.ifq_tail = &ifs->ifs_ips_udpacktq.ifq_head;
236 MUTEX_INIT(&ifs->ifs_ips_udpacktq.ifq_lock, "ipftq udpack tab");
237 ifs->ifs_ips_udpacktq.ifq_next = &ifs->ifs_ips_icmptq;
238 ifs->ifs_ips_icmptq.ifq_ttl = (u_long)ifs->ifs_fr_icmptimeout;
239 ifs->ifs_ips_icmptq.ifq_ref = 1;
240 ifs->ifs_ips_icmptq.ifq_head = NULL;
241 ifs->ifs_ips_icmptq.ifq_tail = &ifs->ifs_ips_icmptq.ifq_head;
242 MUTEX_INIT(&ifs->ifs_ips_icmptq.ifq_lock, "ipftq icmp tab");
243 ifs->ifs_ips_icmptq.ifq_next = &ifs->ifs_ips_icmpacktq;
244 ifs->ifs_ips_icmpacktq.ifq_ttl = (u_long)ifs->ifs_fr_icmpacktimeout;
245 ifs->ifs_ips_icmpacktq.ifq_ref = 1;
246 ifs->ifs_ips_icmpacktq.ifq_head = NULL;
247 ifs->ifs_ips_icmpacktq.ifq_tail = &ifs->ifs_ips_icmpacktq.ifq_head;
248 MUTEX_INIT(&ifs->ifs_ips_icmpacktq.ifq_lock, "ipftq icmpack tab");
249 ifs->ifs_ips_icmpacktq.ifq_next = &ifs->ifs_ips_iptq;
250 ifs->ifs_ips_iptq.ifq_ttl = (u_long)ifs->ifs_fr_iptimeout;
251 ifs->ifs_ips_iptq.ifq_ref = 1;
252 ifs->ifs_ips_iptq.ifq_head = NULL;
253 ifs->ifs_ips_iptq.ifq_tail = &ifs->ifs_ips_iptq.ifq_head;
254 MUTEX_INIT(&ifs->ifs_ips_iptq.ifq_lock, "ipftq ip tab");
255 ifs->ifs_ips_iptq.ifq_next = &ifs->ifs_ips_deletetq;
256 /* entry's ttl in deletetq is just 1 tick */
257 ifs->ifs_ips_deletetq.ifq_ttl = (u_long) 1;
258 ifs->ifs_ips_deletetq.ifq_ref = 1;
259 ifs->ifs_ips_deletetq.ifq_head = NULL;
260 ifs->ifs_ips_deletetq.ifq_tail = &ifs->ifs_ips_deletetq.ifq_head;
261 MUTEX_INIT(&ifs->ifs_ips_deletetq.ifq_lock, "state delete queue");
262 ifs->ifs_ips_deletetq.ifq_next = NULL;
263
264 RWLOCK_INIT(&ifs->ifs_ipf_state, "ipf IP state rwlock");
265 MUTEX_INIT(&ifs->ifs_ipf_stinsert, "ipf state insert mutex");
266 ifs->ifs_fr_state_init = 1;
267
268 ifs->ifs_ips_last_force_flush = ifs->ifs_fr_ticks;
269 return 0;
270 }
271
272
273 /* ------------------------------------------------------------------------ */
274 /* Function: fr_stateunload */
275 /* Returns: Nil */
276 /* Parameters: ifs - ipf stack instance */
277 /* */
278 /* Release and destroy any resources acquired or initialised so that */
279 /* IPFilter can be unloaded or re-initialised. */
280 /* ------------------------------------------------------------------------ */
281 void fr_stateunload(ifs)
282 ipf_stack_t *ifs;
283 {
284 ipftq_t *ifq, *ifqnext;
285 ipstate_t *is;
286
287 while ((is = ifs->ifs_ips_list) != NULL)
288 (void) fr_delstate(is, 0, ifs);
289
290 /*
291 * Proxy timeout queues are not cleaned here because although they
292 * exist on the state list, appr_unload is called after fr_stateunload
293 * and the proxies actually are responsible for them being created.
294 * Should the proxy timeouts have their own list? There's no real
295 * justification as this is the only complicationA
296 */
297 for (ifq = ifs->ifs_ips_utqe; ifq != NULL; ifq = ifqnext) {
298 ifqnext = ifq->ifq_next;
299 if (((ifq->ifq_flags & IFQF_PROXY) == 0) &&
300 (fr_deletetimeoutqueue(ifq) == 0))
301 fr_freetimeoutqueue(ifq, ifs);
302 }
303
304 ifs->ifs_ips_stats.iss_inuse = 0;
305 ifs->ifs_ips_num = 0;
306
307 if (ifs->ifs_fr_state_init == 1) {
308 fr_sttab_destroy(ifs->ifs_ips_tqtqb);
309 MUTEX_DESTROY(&ifs->ifs_ips_udptq.ifq_lock);
310 MUTEX_DESTROY(&ifs->ifs_ips_icmptq.ifq_lock);
311 MUTEX_DESTROY(&ifs->ifs_ips_udpacktq.ifq_lock);
312 MUTEX_DESTROY(&ifs->ifs_ips_icmpacktq.ifq_lock);
313 MUTEX_DESTROY(&ifs->ifs_ips_iptq.ifq_lock);
314 MUTEX_DESTROY(&ifs->ifs_ips_deletetq.ifq_lock);
315 }
316
317 if (ifs->ifs_ips_table != NULL) {
318 KFREES(ifs->ifs_ips_table,
319 ifs->ifs_fr_statesize * sizeof(*ifs->ifs_ips_table));
320 ifs->ifs_ips_table = NULL;
321 }
322
323 if (ifs->ifs_ips_seed != NULL) {
324 KFREES(ifs->ifs_ips_seed,
325 ifs->ifs_fr_statesize * sizeof(*ifs->ifs_ips_seed));
326 ifs->ifs_ips_seed = NULL;
327 }
328
329 if (ifs->ifs_ips_stats.iss_bucketlen != NULL) {
330 KFREES(ifs->ifs_ips_stats.iss_bucketlen,
331 ifs->ifs_fr_statesize * sizeof(u_long));
332 ifs->ifs_ips_stats.iss_bucketlen = NULL;
333 }
334
335 if (ifs->ifs_fr_state_maxbucket_reset == 1)
336 ifs->ifs_fr_state_maxbucket = 0;
337
338 if (ifs->ifs_fr_state_init == 1) {
339 ifs->ifs_fr_state_init = 0;
340 RW_DESTROY(&ifs->ifs_ipf_state);
341 MUTEX_DESTROY(&ifs->ifs_ipf_stinsert);
342 }
343 }
344
345
346 /* ------------------------------------------------------------------------ */
347 /* Function: fr_statetstats */
348 /* Returns: ips_state_t* - pointer to state stats structure */
349 /* Parameters: Nil */
350 /* */
351 /* Put all the current numbers and pointers into a single struct and return */
352 /* a pointer to it. */
353 /* ------------------------------------------------------------------------ */
354 static ips_stat_t *fr_statetstats(ifs)
355 ipf_stack_t *ifs;
356 {
357 ifs->ifs_ips_stats.iss_active = ifs->ifs_ips_num;
358 ifs->ifs_ips_stats.iss_statesize = ifs->ifs_fr_statesize;
359 ifs->ifs_ips_stats.iss_statemax = ifs->ifs_fr_statemax;
360 ifs->ifs_ips_stats.iss_table = ifs->ifs_ips_table;
361 ifs->ifs_ips_stats.iss_list = ifs->ifs_ips_list;
362 ifs->ifs_ips_stats.iss_ticks = ifs->ifs_fr_ticks;
363 return &ifs->ifs_ips_stats;
364 }
365
366 /* ------------------------------------------------------------------------ */
367 /* Function: fr_state_remove */
368 /* Returns: int - 0 == success, != 0 == failure */
369 /* Parameters: data(I) - pointer to state structure to delete from table */
370 /* ifs - ipf stack instance */
371 /* */
372 /* Search for a state structure that matches the one passed, according to */
373 /* the IP addresses and other protocol specific information. */
374 /* ------------------------------------------------------------------------ */
375 static int fr_state_remove(data, ifs)
376 caddr_t data;
377 ipf_stack_t *ifs;
378 {
379 ipstate_t *sp, st;
380 int error;
381
382 sp = &st;
383 error = fr_inobj(data, &st, IPFOBJ_IPSTATE);
384 if (error)
385 return EFAULT;
386
387 WRITE_ENTER(&ifs->ifs_ipf_state);
388 for (sp = ifs->ifs_ips_list; sp; sp = sp->is_next)
389 if ((sp->is_p == st.is_p) && (sp->is_v == st.is_v) &&
390 !bcmp((caddr_t)&sp->is_src, (caddr_t)&st.is_src,
391 sizeof(st.is_src)) &&
392 !bcmp((caddr_t)&sp->is_dst, (caddr_t)&st.is_dst,
393 sizeof(st.is_dst)) &&
394 !bcmp((caddr_t)&sp->is_ps, (caddr_t)&st.is_ps,
395 sizeof(st.is_ps))) {
396 (void) fr_delstate(sp, ISL_REMOVE, ifs);
397 RWLOCK_EXIT(&ifs->ifs_ipf_state);
398 return 0;
399 }
400 RWLOCK_EXIT(&ifs->ifs_ipf_state);
401 return ESRCH;
402 }
403
404
405 /* ------------------------------------------------------------------------ */
406 /* Function: fr_state_ioctl */
407 /* Returns: int - 0 == success, != 0 == failure */
408 /* Parameters: data(I) - pointer to ioctl data */
409 /* cmd(I) - ioctl command integer */
410 /* mode(I) - file mode bits used with open */
411 /* uid(I) - uid of caller */
412 /* ctx(I) - pointer to give the uid context */
413 /* ifs - ipf stack instance */
414 /* */
415 /* Processes an ioctl call made to operate on the IP Filter state device. */
416 /* ------------------------------------------------------------------------ */
417 int fr_state_ioctl(data, cmd, mode, uid, ctx, ifs)
418 caddr_t data;
419 ioctlcmd_t cmd;
420 int mode, uid;
421 void *ctx;
422 ipf_stack_t *ifs;
423 {
424 int arg, ret, error = 0;
425
426 switch (cmd)
427 {
428 /*
429 * Delete an entry from the state table.
430 */
431 case SIOCDELST :
432 error = fr_state_remove(data, ifs);
433 break;
434 /*
435 * Flush the state table
436 */
437 case SIOCIPFFL :
438 error = BCOPYIN(data, (char *)&arg, sizeof(arg));
439 if (error != 0) {
440 error = EFAULT;
441 } else {
442 if (VALID_TABLE_FLUSH_OPT(arg)) {
443 WRITE_ENTER(&ifs->ifs_ipf_state);
444 ret = fr_state_flush(arg, 4, ifs);
445 RWLOCK_EXIT(&ifs->ifs_ipf_state);
446 error = BCOPYOUT((char *)&ret, data,
447 sizeof(ret));
448 if (error != 0)
449 return EFAULT;
450 } else {
451 error = EINVAL;
452 }
453 }
454 break;
455
456 #ifdef USE_INET6
457 case SIOCIPFL6 :
458 error = BCOPYIN(data, (char *)&arg, sizeof(arg));
459 if (error != 0) {
460 error = EFAULT;
461 } else {
462 if (VALID_TABLE_FLUSH_OPT(arg)) {
463 WRITE_ENTER(&ifs->ifs_ipf_state);
464 ret = fr_state_flush(arg, 6, ifs);
465 RWLOCK_EXIT(&ifs->ifs_ipf_state);
466 error = BCOPYOUT((char *)&ret, data,
467 sizeof(ret));
468 if (error != 0)
469 return EFAULT;
470 } else {
471 error = EINVAL;
472 }
473 }
474 break;
475 #endif
476 #ifdef IPFILTER_LOG
477 /*
478 * Flush the state log.
479 */
480 case SIOCIPFFB :
481 if (!(mode & FWRITE))
482 error = EPERM;
483 else {
484 int tmp;
485
486 tmp = ipflog_clear(IPL_LOGSTATE, ifs);
487 error = BCOPYOUT((char *)&tmp, data, sizeof(tmp));
488 if (error != 0)
489 error = EFAULT;
490 }
491 break;
492 /*
493 * Turn logging of state information on/off.
494 */
495 case SIOCSETLG :
496 if (!(mode & FWRITE)) {
497 error = EPERM;
498 } else {
499 error = BCOPYIN((char *)data,
500 (char *)&ifs->ifs_ipstate_logging,
501 sizeof(ifs->ifs_ipstate_logging));
502 if (error != 0)
503 error = EFAULT;
504 }
505 break;
506 /*
507 * Return the current state of logging.
508 */
509 case SIOCGETLG :
510 error = BCOPYOUT((char *)&ifs->ifs_ipstate_logging,
511 (char *)data,
512 sizeof(ifs->ifs_ipstate_logging));
513 if (error != 0)
514 error = EFAULT;
515 break;
516 /*
517 * Return the number of bytes currently waiting to be read.
518 */
519 case FIONREAD :
520 arg = ifs->ifs_iplused[IPL_LOGSTATE]; /* returned in an int */
521 error = BCOPYOUT((char *)&arg, data, sizeof(arg));
522 if (error != 0)
523 error = EFAULT;
524 break;
525 #endif
526 /*
527 * Get the current state statistics.
528 */
529 case SIOCGETFS :
530 error = fr_outobj(data, fr_statetstats(ifs), IPFOBJ_STATESTAT);
531 break;
532 /*
533 * Lock/Unlock the state table. (Locking prevents any changes, which
534 * means no packets match).
535 */
536 case SIOCSTLCK :
537 if (!(mode & FWRITE)) {
538 error = EPERM;
539 } else {
540 error = fr_lock(data, &ifs->ifs_fr_state_lock);
541 }
542 break;
543 /*
544 * Add an entry to the current state table.
545 */
546 case SIOCSTPUT :
547 if (!ifs->ifs_fr_state_lock || !(mode & FWRITE)) {
548 error = EACCES;
549 break;
550 }
551 error = fr_stputent(data, ifs);
552 break;
553 /*
554 * Get a state table entry.
555 */
556 case SIOCSTGET :
557 if (!ifs->ifs_fr_state_lock) {
558 error = EACCES;
559 break;
560 }
561 error = fr_stgetent(data, ifs);
562 break;
563
564 case SIOCGENITER :
565 {
566 ipftoken_t *token;
567 ipfgeniter_t iter;
568
569 error = fr_inobj(data, &iter, IPFOBJ_GENITER);
570 if (error != 0)
571 break;
572
573 token = ipf_findtoken(IPFGENITER_STATE, uid, ctx, ifs);
574 if (token != NULL)
575 error = fr_stateiter(token, &iter, ifs);
576 else
577 error = ESRCH;
578 RWLOCK_EXIT(&ifs->ifs_ipf_tokens);
579 break;
580 }
581
582 case SIOCIPFDELTOK :
583 error = BCOPYIN(data, (char *)&arg, sizeof(arg));
584 if (error != 0) {
585 error = EFAULT;
586 } else {
587 error = ipf_deltoken(arg, uid, ctx, ifs);
588 }
589 break;
590
591 default :
592 error = EINVAL;
593 break;
594 }
595 return error;
596 }
597
598
599 /* ------------------------------------------------------------------------ */
600 /* Function: fr_stgetent */
601 /* Returns: int - 0 == success, != 0 == failure */
602 /* Parameters: data(I) - pointer to state structure to retrieve from table */
603 /* */
604 /* Copy out state information from the kernel to a user space process. If */
605 /* there is a filter rule associated with the state entry, copy that out */
606 /* as well. The entry to copy out is taken from the value of "ips_next" in */
607 /* the struct passed in and if not null and not found in the list of current*/
608 /* state entries, the retrieval fails. */
609 /* ------------------------------------------------------------------------ */
610 int fr_stgetent(data, ifs)
611 caddr_t data;
612 ipf_stack_t *ifs;
613 {
614 ipstate_t *is, *isn;
615 ipstate_save_t ips;
616 int error;
617
618 error = fr_inobj(data, &ips, IPFOBJ_STATESAVE);
619 if (error)
620 return EFAULT;
621
622 isn = ips.ips_next;
623 if (isn == NULL) {
624 isn = ifs->ifs_ips_list;
625 if (isn == NULL) {
626 if (ips.ips_next == NULL)
627 return ENOENT;
628 return 0;
629 }
630 } else {
631 /*
632 * Make sure the pointer we're copying from exists in the
633 * current list of entries. Security precaution to prevent
634 * copying of random kernel data.
635 */
636 for (is = ifs->ifs_ips_list; is; is = is->is_next)
637 if (is == isn)
638 break;
639 if (!is)
640 return ESRCH;
641 }
642 ips.ips_next = isn->is_next;
643 bcopy((char *)isn, (char *)&ips.ips_is, sizeof(ips.ips_is));
644 ips.ips_rule = isn->is_rule;
645 if (isn->is_rule != NULL)
646 bcopy((char *)isn->is_rule, (char *)&ips.ips_fr,
647 sizeof(ips.ips_fr));
648 error = fr_outobj(data, &ips, IPFOBJ_STATESAVE);
649 if (error)
650 return EFAULT;
651 return 0;
652 }
653
654
655 /* ------------------------------------------------------------------------ */
656 /* Function: fr_stputent */
657 /* Returns: int - 0 == success, != 0 == failure */
658 /* Parameters: data(I) - pointer to state information struct */
659 /* ifs - ipf stack instance */
660 /* */
661 /* This function implements the SIOCSTPUT ioctl: insert a state entry into */
662 /* the state table. If the state info. includes a pointer to a filter rule */
663 /* then also add in an orphaned rule (will not show up in any "ipfstat -io" */
664 /* output. */
665 /* ------------------------------------------------------------------------ */
666 int fr_stputent(data, ifs)
667 caddr_t data;
668 ipf_stack_t *ifs;
669 {
670 ipstate_t *is, *isn;
671 ipstate_save_t ips;
672 int error, i;
673 frentry_t *fr;
674 char *name;
675
676 error = fr_inobj(data, &ips, IPFOBJ_STATESAVE);
677 if (error)
678 return EFAULT;
679
680 /*
681 * Trigger automatic call to fr_state_flush() if the
682 * table has reached capacity specified by hi watermark.
683 */
684 if (ST_TAB_WATER_LEVEL(ifs) > ifs->ifs_state_flush_level_hi)
685 ifs->ifs_fr_state_doflush = 1;
686
687 /*
688 * If automatic flushing did not do its job, and the table
689 * has filled up, don't try to create a new entry.
690 */
691 if (ifs->ifs_ips_num >= ifs->ifs_fr_statemax) {
692 ATOMIC_INCL(ifs->ifs_ips_stats.iss_max);
693 return ENOMEM;
694 }
695
696 KMALLOC(isn, ipstate_t *);
697 if (isn == NULL)
698 return ENOMEM;
699
700 bcopy((char *)&ips.ips_is, (char *)isn, sizeof(*isn));
701 bzero((char *)isn, offsetof(struct ipstate, is_pkts));
702 isn->is_sti.tqe_pnext = NULL;
703 isn->is_sti.tqe_next = NULL;
704 isn->is_sti.tqe_ifq = NULL;
705 isn->is_sti.tqe_parent = isn;
706 isn->is_ifp[0] = NULL;
707 isn->is_ifp[1] = NULL;
708 isn->is_ifp[2] = NULL;
709 isn->is_ifp[3] = NULL;
710 isn->is_sync = NULL;
711 fr = ips.ips_rule;
712
713 if (fr == NULL) {
714 READ_ENTER(&ifs->ifs_ipf_state);
715 fr_stinsert(isn, 0, ifs);
716 MUTEX_EXIT(&isn->is_lock);
717 RWLOCK_EXIT(&ifs->ifs_ipf_state);
718 return 0;
719 }
720
721 if (isn->is_flags & SI_NEWFR) {
722 KMALLOC(fr, frentry_t *);
723 if (fr == NULL) {
724 KFREE(isn);
725 return ENOMEM;
726 }
727 bcopy((char *)&ips.ips_fr, (char *)fr, sizeof(*fr));
728 isn->is_rule = fr;
729 ips.ips_is.is_rule = fr;
730 MUTEX_NUKE(&fr->fr_lock);
731 MUTEX_INIT(&fr->fr_lock, "state filter rule lock");
732
733 /*
734 * Look up all the interface names in the rule.
735 */
736 for (i = 0; i < 4; i++) {
737 name = fr->fr_ifnames[i];
738 fr->fr_ifas[i] = fr_resolvenic(name, fr->fr_v, ifs);
739 name = isn->is_ifname[i];
740 isn->is_ifp[i] = fr_resolvenic(name, isn->is_v, ifs);
741 }
742
743 fr->fr_ref = 0;
744 fr->fr_dsize = 0;
745 fr->fr_data = NULL;
746 fr->fr_type = FR_T_NONE;
747
748 fr_resolvedest(&fr->fr_tif, fr->fr_v, ifs);
749 fr_resolvedest(&fr->fr_dif, fr->fr_v, ifs);
750 fr_resolvedest(&fr->fr_rif, fr->fr_v, ifs);
751
752 /*
753 * send a copy back to userland of what we ended up
754 * to allow for verification.
755 */
756 error = fr_outobj(data, &ips, IPFOBJ_STATESAVE);
757 if (error) {
758 KFREE(isn);
759 MUTEX_DESTROY(&fr->fr_lock);
760 KFREE(fr);
761 return EFAULT;
762 }
763 READ_ENTER(&ifs->ifs_ipf_state);
764 fr_stinsert(isn, 0, ifs);
765 MUTEX_EXIT(&isn->is_lock);
766 RWLOCK_EXIT(&ifs->ifs_ipf_state);
767
768 } else {
769 READ_ENTER(&ifs->ifs_ipf_state);
770 for (is = ifs->ifs_ips_list; is; is = is->is_next)
771 if (is->is_rule == fr) {
772 fr_stinsert(isn, 0, ifs);
773 MUTEX_EXIT(&isn->is_lock);
774 break;
775 }
776
777 if (is == NULL) {
778 KFREE(isn);
779 isn = NULL;
780 }
781 RWLOCK_EXIT(&ifs->ifs_ipf_state);
782
783 return (isn == NULL) ? ESRCH : 0;
784 }
785
786 return 0;
787 }
788
789
790 /* ------------------------------------------------------------------------ */
791 /* Function: fr_stinsert */
792 /* Returns: Nil */
793 /* Parameters: is(I) - pointer to state structure */
794 /* rev(I) - flag indicating forward/reverse direction of packet */
795 /* */
796 /* Inserts a state structure into the hash table (for lookups) and the list */
797 /* of state entries (for enumeration). Resolves all of the interface names */
798 /* to pointers and adjusts running stats for the hash table as appropriate. */
799 /* */
800 /* Locking: it is assumed that some kind of lock on ipf_state is held. */
801 /* Exits with is_lock initialised and held. */
802 /* ------------------------------------------------------------------------ */
803 void fr_stinsert(is, rev, ifs)
804 ipstate_t *is;
805 int rev;
806 ipf_stack_t *ifs;
807 {
808 frentry_t *fr;
809 u_int hv;
810 int i;
811
812 MUTEX_INIT(&is->is_lock, "ipf state entry");
813
814 fr = is->is_rule;
815 if (fr != NULL) {
816 MUTEX_ENTER(&fr->fr_lock);
817 fr->fr_ref++;
818 fr->fr_statecnt++;
819 MUTEX_EXIT(&fr->fr_lock);
820 }
821
822 /*
823 * Look up all the interface names in the state entry.
824 */
825 for (i = 0; i < 4; i++) {
826 if (is->is_ifp[i] != NULL)
827 continue;
828 is->is_ifp[i] = fr_resolvenic(is->is_ifname[i], is->is_v, ifs);
829 }
830
831 /*
832 * If we could trust is_hv, then the modulous would not be needed, but
833 * when running with IPFILTER_SYNC, this stops bad values.
834 */
835 hv = is->is_hv % ifs->ifs_fr_statesize;
836 is->is_hv = hv;
837
838 /*
839 * We need to get both of these locks...the first because it is
840 * possible that once the insert is complete another packet might
841 * come along, match the entry and want to update it.
842 */
843 MUTEX_ENTER(&is->is_lock);
844 MUTEX_ENTER(&ifs->ifs_ipf_stinsert);
845
846 /*
847 * add into list table.
848 */
849 if (ifs->ifs_ips_list != NULL)
850 ifs->ifs_ips_list->is_pnext = &is->is_next;
851 is->is_pnext = &ifs->ifs_ips_list;
852 is->is_next = ifs->ifs_ips_list;
853 ifs->ifs_ips_list = is;
854
855 if (ifs->ifs_ips_table[hv] != NULL)
856 ifs->ifs_ips_table[hv]->is_phnext = &is->is_hnext;
857 else
858 ifs->ifs_ips_stats.iss_inuse++;
859 is->is_phnext = ifs->ifs_ips_table + hv;
860 is->is_hnext = ifs->ifs_ips_table[hv];
861 ifs->ifs_ips_table[hv] = is;
862 ifs->ifs_ips_stats.iss_bucketlen[hv]++;
863 ifs->ifs_ips_num++;
864 MUTEX_EXIT(&ifs->ifs_ipf_stinsert);
865
866 fr_setstatequeue(is, rev, ifs);
867 }
868
869 /* ------------------------------------------------------------------------ */
870 /* Function: fr_match_ipv4addrs */
871 /* Returns: int - 2 strong match (same addresses, same direction) */
872 /* 1 weak match (same address, opposite direction) */
873 /* 0 no match */
874 /* */
875 /* Function matches IPv4 addresses. */
876 /* ------------------------------------------------------------------------ */
877 static int fr_match_ipv4addrs(is1, is2)
878 ipstate_t *is1;
879 ipstate_t *is2;
880 {
881 int rv;
882
883 if (is1->is_saddr == is2->is_saddr && is1->is_daddr == is2->is_daddr)
884 rv = 2;
885 else if (is1->is_saddr == is2->is_daddr &&
886 is1->is_daddr == is2->is_saddr)
887 rv = 1;
888 else
889 rv = 0;
890
891 return (rv);
892 }
893
894 /* ------------------------------------------------------------------------ */
895 /* Function: fr_match_ipv6addrs */
896 /* Returns: int - 2 strong match (same addresses, same direction) */
897 /* 1 weak match (same addresses, opposite direction) */
898 /* 0 no match */
899 /* */
900 /* Function matches IPv6 addresses. */
901 /* ------------------------------------------------------------------------ */
902 static int fr_match_ipv6addrs(is1, is2)
903 ipstate_t *is1;
904 ipstate_t *is2;
905 {
906 int rv;
907
908 if (IP6_EQ(&is1->is_src, &is2->is_src) &&
909 IP6_EQ(&is1->is_dst, &is2->is_dst))
910 rv = 2;
911 else if (IP6_EQ(&is1->is_src, &is2->is_dst) &&
912 IP6_EQ(&is1->is_dst, &is2->is_src)) {
913 rv = 1;
914 }
915 else
916 rv = 0;
917
918 return (rv);
919 }
920 /* ------------------------------------------------------------------------ */
921 /* Function: fr_match_addresses */
922 /* Returns: int - 2 strong match (same addresses, same direction) */
923 /* 1 weak match (same address, opposite directions) */
924 /* 0 no match */
925 /* Parameters: is1, is2 pointers to states we are checking */
926 /* */
927 /* Matches addresses, function uses fr_match_ipvXaddrs() to deal with IPv4 */
928 /* and IPv6 address format. */
929 /* ------------------------------------------------------------------------ */
930 static int fr_match_addresses(is1, is2)
931 ipstate_t *is1;
932 ipstate_t *is2;
933 {
934 int rv;
935
936 if (is1->is_v == 4) {
937 rv = fr_match_ipv4addrs(is1, is2);
938 } else {
939 rv = fr_match_ipv6addrs(is1, is2);
940 }
941
942 return (rv);
943 }
944
945 /* ------------------------------------------------------------------------ */
946 /* Function: fr_match_ppairs */
947 /* Returns: int - 2 strong match (same ports, same direction) */
948 /* 1 weak match (same ports, different direction) */
949 /* 0 no match */
950 /* Parameters ppairs1, ppairs - src, dst ports we want to match. */
951 /* */
952 /* Matches two port_pair_t types (port pairs). Each port pair contains */
953 /* src, dst port, which belong to session (state entry). */
954 /* ------------------------------------------------------------------------ */
955 static int fr_match_ppairs(ppairs1, ppairs2)
956 port_pair_t *ppairs1;
957 port_pair_t *ppairs2;
958 {
959 int rv;
960
961 if (ppairs1->pp_sport == ppairs2->pp_sport &&
962 ppairs1->pp_dport == ppairs2->pp_dport)
963 rv = 2;
964 else if (ppairs1->pp_sport == ppairs2->pp_dport &&
965 ppairs1->pp_dport == ppairs2->pp_sport)
966 rv = 1;
967 else
968 rv = 0;
969
970 return (rv);
971 }
972
973 /* ------------------------------------------------------------------------ */
974 /* Function: fr_match_l4_hdr */
975 /* Returns: int - 0 no match, */
976 /* 1 weak match (same ports, different directions) */
977 /* 2 strong match (same ports, same direction) */
978 /* Parameters is1, is2 - states we want to match */
979 /* */
980 /* Function matches L4 header data (source ports for TCP, UDP, CallIds for */
981 /* GRE protocol). */
982 /* ------------------------------------------------------------------------ */
983 static int fr_match_l4_hdr(is1, is2)
984 ipstate_t *is1;
985 ipstate_t *is2;
986 {
987 int rv = 0;
988 port_pair_t pp1;
989 port_pair_t pp2;
990
991 if (is1->is_p != is2->is_p)
992 return (0);
993
994 switch (is1->is_p) {
995 case IPPROTO_TCP:
996 pp1.pp_sport = is1->is_ps.is_ts.ts_sport;
997 pp1.pp_dport = is1->is_ps.is_ts.ts_dport;
998 pp2.pp_sport = is2->is_ps.is_ts.ts_sport;
999 pp2.pp_dport = is2->is_ps.is_ts.ts_dport;
1000 rv = fr_match_ppairs(&pp1, &pp2);
1001 break;
1002 case IPPROTO_UDP:
1003 pp1.pp_sport = is1->is_ps.is_us.us_sport;
1004 pp1.pp_dport = is1->is_ps.is_us.us_dport;
1005 pp2.pp_sport = is2->is_ps.is_us.us_sport;
1006 pp2.pp_dport = is2->is_ps.is_us.us_dport;
1007 rv = fr_match_ppairs(&pp1, &pp2);
1008 break;
1009 case IPPROTO_GRE:
1010 /* greinfo_t can be also interprted as port pair */
1011 pp1.pp_sport = is1->is_ps.is_ug.gs_call[0];
1012 pp1.pp_dport = is1->is_ps.is_ug.gs_call[1];
1013 pp2.pp_sport = is2->is_ps.is_ug.gs_call[0];
1014 pp2.pp_dport = is2->is_ps.is_ug.gs_call[1];
1015 rv = fr_match_ppairs(&pp1, &pp2);
1016 break;
1017 case IPPROTO_ICMP:
1018 case IPPROTO_ICMPV6:
1019 if (bcmp(&is1->is_ps, &is2->is_ps, sizeof (icmpinfo_t)))
1020 rv = 1;
1021 else
1022 rv = 0;
1023 break;
1024 default:
1025 rv = 0;
1026 }
1027
1028 return (rv);
1029 }
1030
1031 /* ------------------------------------------------------------------------ */
1032 /* Function: fr_matchstates */
1033 /* Returns: int - nonzero match, zero no match */
1034 /* Parameters is1, is2 - states we want to match */
1035 /* */
1036 /* The state entries are equal (identical match) if they belong to the same */
1037 /* session. Any time new state entry is being added the fr_addstate() */
1038 /* function creates temporal state entry from the data it gets from IP and */
1039 /* L4 header. The fr_matchstats() must be also aware of packet direction, */
1040 /* which is also stored within the state entry. We should keep in mind the */
1041 /* information about packet direction is spread accross L3 (addresses) and */
1042 /* L4 (ports). There are three possible relationships betwee is1, is2: */
1043 /* - no match (match(is1, is2) == 0)) */
1044 /* - weak match same addresses (ports), but different */
1045 /* directions (1) (fr_match_xxxx(is1, is2) == 1) */
1046 /* - strong match same addresses (ports) and same directions */
1047 /* (2) (fr_match_xxxx(is1, is2) == 2) */
1048 /* */
1049 /* There are functions, which match match addresses (L3 header) in is1, is2 */
1050 /* and functions, which are used to compare ports (L4 header) data. We say */
1051 /* the is1 and is2 are same (identical) if there is a match */
1052 /* (fr_match_l4_hdr(is1, is2) != 0) and matchlevels are same for entries */
1053 /* (fr_match_l3_hdr(is1, is2) == fr_match_l4_hdr(is1, is2)) for is1, is2. */
1054 /* Such requirement deals with case as follows: */
1055 /* suppose there are two connections between hosts A, B. Connection 1: */
1056 /* a.a.a.a:12345 <=> b.b.b.b:54321 */
1057 /* Connection 2: */
1058 /* a.a.a.a:54321 <=> b.b.b.b:12345 */
1059 /* since we've introduced match levels into our fr_matchstates(), we are */
1060 /* able to identify, which packets belong to connection A and which belong */
1061 /* to connection B. Assume there are two entries is1, is2. is1 has been */
1062 /* from con. 1 packet, which travelled from A to B: */
1063 /* a.a.a.a:12345 -> b.b.b.b:54321 */
1064 /* while s2, has been created from packet which belongs to con. 2 and is */
1065 /* also coming from A to B: */
1066 /* a.a.a.a:54321 -> b.b.b.b:12345 */
1067 /* fr_match_l3_hdr(is1, is2) == 2 -> strong match, while */
1068 /* fr_match_l4_hdr(is1, is2) == 1 -> weak match. Since match levels are */
1069 /* different the state entries are not identical -> no match as a final */
1070 /* result. */
1071 /* ------------------------------------------------------------------------ */
1072 static int fr_matchstates(is1, is2)
1073 ipstate_t *is1;
1074 ipstate_t *is2;
1075 {
1076 int rv;
1077 int amatch;
1078 int pmatch;
1079
1080 if (bcmp(&is1->is_pass, &is2->is_pass,
1081 offsetof(struct ipstate, is_ps) -
1082 offsetof(struct ipstate, is_pass)) == 0) {
1083
1084 pmatch = fr_match_l4_hdr(is1, is2);
1085 amatch = fr_match_addresses(is1, is2);
1086 /*
1087 * If addresses match (amatch != 0), then 'match levels'
1088 * must be same for matching entries. If amatch and pmatch
1089 * have different values (different match levels), then
1090 * is1 and is2 belong to different sessions.
1091 */
1092 rv = (amatch != 0) && (amatch == pmatch);
1093 }
1094 else
1095 rv = 0;
1096
1097 return (rv);
1098 }
1099
1100 /* ------------------------------------------------------------------------ */
1101 /* Function: fr_addstate */
1102 /* Returns: ipstate_t* - NULL == failure, else pointer to new state */
1103 /* Parameters: fin(I) - pointer to packet information */
1104 /* stsave(O) - pointer to place to save pointer to created */
1105 /* state structure. */
1106 /* flags(I) - flags to use when creating the structure */
1107 /* */
1108 /* Creates a new IP state structure from the packet information collected. */
1109 /* Inserts it into the state table and appends to the bottom of the active */
1110 /* list. If the capacity of the table has reached the maximum allowed then */
1111 /* the call will fail and a flush is scheduled for the next timeout call. */
1112 /* ------------------------------------------------------------------------ */
1113 ipstate_t *fr_addstate(fin, stsave, flags)
1114 fr_info_t *fin;
1115 ipstate_t **stsave;
1116 u_int flags;
1117 {
1118 ipstate_t *is, ips;
1119 struct icmp *ic;
1120 u_int pass, hv;
1121 frentry_t *fr;
1122 tcphdr_t *tcp;
1123 grehdr_t *gre;
1124 void *ifp;
1125 int out;
1126 ipf_stack_t *ifs = fin->fin_ifs;
1127
1128 if (ifs->ifs_fr_state_lock ||
1129 (fin->fin_flx & (FI_SHORT|FI_STATE|FI_FRAGBODY|FI_BAD)))
1130 return NULL;
1131
1132 if ((fin->fin_flx & FI_OOW) && !(fin->fin_tcpf & TH_SYN))
1133 return NULL;
1134
1135 /*
1136 * Trigger automatic call to fr_state_flush() if the
1137 * table has reached capacity specified by hi watermark.
1138 */
1139 if (ST_TAB_WATER_LEVEL(ifs) > ifs->ifs_state_flush_level_hi)
1140 ifs->ifs_fr_state_doflush = 1;
1141
1142 /*
1143 * If the max number of state entries has been reached, and there is no
1144 * limit on the state count for the rule, then do not continue. In the
1145 * case where a limit exists, it's ok allow the entries to be created as
1146 * long as specified limit itself has not been reached.
1147 *
1148 * Note that because the lock isn't held on fr, it is possible to exceed
1149 * the specified size of the table. However, the cost of this is being
1150 * ignored here; as the number by which it can go over is a product of
1151 * the number of simultaneous threads that could be executing in here.
1152 * So, a limit of 100 won't result in 200, but could result in 101 or 102.
1153 *
1154 * Also note that, since the automatic flush should have been triggered
1155 * well before we reach the maximum number of state table entries, the
1156 * likelihood of reaching the max (and thus exceedng it) is minimal.
1157 */
1158 fr = fin->fin_fr;
1159 if (fr != NULL) {
1160 if ((ifs->ifs_ips_num >= ifs->ifs_fr_statemax) &&
1161 (fr->fr_statemax == 0)) {
1162 ATOMIC_INCL(ifs->ifs_ips_stats.iss_max);
1163 return NULL;
1164 }
1165 if ((fr->fr_statemax != 0) &&
1166 (fr->fr_statecnt >= fr->fr_statemax)) {
1167 ATOMIC_INCL(ifs->ifs_ips_stats.iss_maxref);
1168 ifs->ifs_fr_state_doflush = 1;
1169 return NULL;
1170 }
1171 }
1172
1173 ic = NULL;
1174 tcp = NULL;
1175 out = fin->fin_out;
1176 is = &ips;
1177 bzero((char *)is, sizeof(*is));
1178
1179 if (fr == NULL) {
1180 pass = ifs->ifs_fr_flags;
1181 is->is_tag = FR_NOLOGTAG;
1182 } else {
1183 pass = fr->fr_flags;
1184 }
1185
1186 is->is_die = 1 + ifs->ifs_fr_ticks;
1187 /*
1188 * We want to check everything that is a property of this packet,
1189 * but we don't (automatically) care about it's fragment status as
1190 * this may change.
1191 */
1192 is->is_pass = pass;
1193 is->is_v = fin->fin_v;
1194 is->is_opt[0] = fin->fin_optmsk;
1195 is->is_optmsk[0] = 0xffffffff;
1196 /*
1197 * The reverse direction option mask will be set in fr_matchsrcdst(),
1198 * when we will see the first packet from the peer. We will leave it
1199 * as zero for now.
1200 */
1201 is->is_optmsk[1] = 0x0;
1202
1203 if (is->is_v == 6) {
1204 is->is_opt[0] &= ~0x8;
1205 is->is_optmsk[0] &= ~0x8;
1206 }
1207 is->is_sec = fin->fin_secmsk;
1208 is->is_secmsk = 0xffff;
1209 is->is_auth = fin->fin_auth;
1210 is->is_authmsk = 0xffff;
1211
1212 /*
1213 * Copy and calculate...
1214 */
1215 hv = (is->is_p = fin->fin_fi.fi_p);
1216 is->is_src = fin->fin_fi.fi_src;
1217 hv += is->is_saddr;
1218 is->is_dst = fin->fin_fi.fi_dst;
1219 hv += is->is_daddr;
1220 #ifdef USE_INET6
1221 if (fin->fin_v == 6) {
1222 /*
1223 * For ICMPv6, we check to see if the destination address is
1224 * a multicast address. If it is, do not include it in the
1225 * calculation of the hash because the correct reply will come
1226 * back from a real address, not a multicast address.
1227 */
1228 if ((is->is_p == IPPROTO_ICMPV6) &&
1229 IN6_IS_ADDR_MULTICAST(&is->is_dst.in6)) {
1230 /*
1231 * So you can do keep state with neighbour discovery.
1232 *
1233 * Here we could use the address from the neighbour
1234 * solicit message to put in the state structure and
1235 * we could use that without a wildcard flag too...
1236 */
1237 is->is_flags |= SI_W_DADDR;
1238 hv -= is->is_daddr;
1239 } else {
1240 hv += is->is_dst.i6[1];
1241 hv += is->is_dst.i6[2];
1242 hv += is->is_dst.i6[3];
1243 }
1244 hv += is->is_src.i6[1];
1245 hv += is->is_src.i6[2];
1246 hv += is->is_src.i6[3];
1247 }
1248 #endif
1249 if ((fin->fin_v == 4) &&
1250 (fin->fin_flx & (FI_MULTICAST|FI_BROADCAST|FI_MBCAST))) {
1251 if (fin->fin_out == 0) {
1252 flags |= SI_W_DADDR|SI_CLONE;
1253 hv -= is->is_daddr;
1254 } else {
1255 flags |= SI_W_SADDR|SI_CLONE;
1256 hv -= is->is_saddr;
1257 }
1258 }
1259
1260 switch (is->is_p)
1261 {
1262 #ifdef USE_INET6
1263 case IPPROTO_ICMPV6 :
1264 ic = fin->fin_dp;
1265
1266 switch (ic->icmp_type)
1267 {
1268 case ICMP6_ECHO_REQUEST :
1269 is->is_icmp.ici_type = ic->icmp_type;
1270 hv += (is->is_icmp.ici_id = ic->icmp_id);
1271 break;
1272 case ICMP6_MEMBERSHIP_QUERY :
1273 case ND_ROUTER_SOLICIT :
1274 case ND_NEIGHBOR_SOLICIT :
1275 case ICMP6_NI_QUERY :
1276 is->is_icmp.ici_type = ic->icmp_type;
1277 break;
1278 default :
1279 return NULL;
1280 }
1281 ATOMIC_INCL(ifs->ifs_ips_stats.iss_icmp);
1282 break;
1283 #endif
1284 case IPPROTO_ICMP :
1285 ic = fin->fin_dp;
1286
1287 switch (ic->icmp_type)
1288 {
1289 case ICMP_ECHO :
1290 case ICMP_ECHOREPLY :
1291 case ICMP_TSTAMP :
1292 case ICMP_IREQ :
1293 case ICMP_MASKREQ :
1294 is->is_icmp.ici_type = ic->icmp_type;
1295 hv += (is->is_icmp.ici_id = ic->icmp_id);
1296 break;
1297 default :
1298 return NULL;
1299 }
1300 ATOMIC_INCL(ifs->ifs_ips_stats.iss_icmp);
1301 break;
1302
1303 case IPPROTO_GRE :
1304 gre = fin->fin_dp;
1305
1306 is->is_gre.gs_flags = gre->gr_flags;
1307 is->is_gre.gs_ptype = gre->gr_ptype;
1308 if (GRE_REV(is->is_gre.gs_flags) == 1) {
1309 is->is_call[0] = fin->fin_data[0];
1310 is->is_call[1] = fin->fin_data[1];
1311 }
1312 break;
1313
1314 case IPPROTO_TCP :
1315 tcp = fin->fin_dp;
1316
1317 if (tcp->th_flags & TH_RST)
1318 return NULL;
1319 /*
1320 * The endian of the ports doesn't matter, but the ack and
1321 * sequence numbers do as we do mathematics on them later.
1322 */
1323 is->is_sport = htons(fin->fin_data[0]);
1324 is->is_dport = htons(fin->fin_data[1]);
1325 if ((flags & (SI_W_DPORT|SI_W_SPORT)) == 0) {
1326 hv += is->is_sport;
1327 hv += is->is_dport;
1328 }
1329
1330 /*
1331 * If this is a real packet then initialise fields in the
1332 * state information structure from the TCP header information.
1333 */
1334
1335 is->is_maxdwin = 1;
1336 is->is_maxswin = ntohs(tcp->th_win);
1337 if (is->is_maxswin == 0)
1338 is->is_maxswin = 1;
1339
1340 if ((fin->fin_flx & FI_IGNORE) == 0) {
1341 is->is_send = ntohl(tcp->th_seq) + fin->fin_dlen -
1342 (TCP_OFF(tcp) << 2) +
1343 ((tcp->th_flags & TH_SYN) ? 1 : 0) +
1344 ((tcp->th_flags & TH_FIN) ? 1 : 0);
1345 is->is_maxsend = is->is_send;
1346
1347 /*
1348 * Window scale option is only present in
1349 * SYN/SYN-ACK packet.
1350 */
1351 if ((tcp->th_flags & ~(TH_FIN|TH_ACK|TH_ECNALL)) ==
1352 TH_SYN &&
1353 (TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2))) {
1354 if (fr_tcpoptions(fin, tcp,
1355 &is->is_tcp.ts_data[0]) == -1) {
1356 fin->fin_flx |= FI_BAD;
1357 }
1358 }
1359
1360 if ((fin->fin_out != 0) && (pass & FR_NEWISN) != 0) {
1361 fr_checknewisn(fin, is);
1362 fr_fixoutisn(fin, is);
1363 }
1364
1365 if ((tcp->th_flags & TH_OPENING) == TH_SYN)
1366 flags |= IS_TCPFSM;
1367 else {
1368 is->is_maxdwin = is->is_maxswin * 2;
1369 is->is_dend = ntohl(tcp->th_ack);
1370 is->is_maxdend = ntohl(tcp->th_ack);
1371 is->is_maxdwin *= 2;
1372 }
1373 }
1374
1375 /*
1376 * If we're creating state for a starting connection, start the
1377 * timer on it as we'll never see an error if it fails to
1378 * connect.
1379 */
1380 ATOMIC_INCL(ifs->ifs_ips_stats.iss_tcp);
1381 break;
1382
1383 case IPPROTO_UDP :
1384 tcp = fin->fin_dp;
1385
1386 is->is_sport = htons(fin->fin_data[0]);
1387 is->is_dport = htons(fin->fin_data[1]);
1388 if ((flags & (SI_W_DPORT|SI_W_SPORT)) == 0) {
1389 hv += tcp->th_dport;
1390 hv += tcp->th_sport;
1391 }
1392 ATOMIC_INCL(ifs->ifs_ips_stats.iss_udp);
1393 break;
1394
1395 default :
1396 break;
1397 }
1398 hv = DOUBLE_HASH(hv, ifs);
1399 is->is_hv = hv;
1400 is->is_rule = fr;
1401 is->is_flags = flags & IS_INHERITED;
1402
1403 /*
1404 * Look for identical state.
1405 */
1406 for (is = ifs->ifs_ips_table[is->is_hv % ifs->ifs_fr_statesize];
1407 is != NULL;
1408 is = is->is_hnext) {
1409 if (fr_matchstates(&ips, is) == 1)
1410 break;
1411 }
1412
1413 /*
1414 * we've found a matching state -> state already exists,
1415 * we are not going to add a duplicate record.
1416 */
1417 if (is != NULL)
1418 return NULL;
1419
1420 if (ifs->ifs_ips_stats.iss_bucketlen[hv] >= ifs->ifs_fr_state_maxbucket) {
1421 ATOMIC_INCL(ifs->ifs_ips_stats.iss_bucketfull);
1422 return NULL;
1423 }
1424 KMALLOC(is, ipstate_t *);
1425 if (is == NULL) {
1426 ATOMIC_INCL(ifs->ifs_ips_stats.iss_nomem);
1427 return NULL;
1428 }
1429 bcopy((char *)&ips, (char *)is, sizeof(*is));
1430 /*
1431 * Do not do the modulous here, it is done in fr_stinsert().
1432 */
1433 if (fr != NULL) {
1434 (void) strncpy(is->is_group, fr->fr_group, FR_GROUPLEN);
1435 if (fr->fr_age[0] != 0) {
1436 is->is_tqehead[0] =
1437 fr_addtimeoutqueue(&ifs->ifs_ips_utqe,
1438 fr->fr_age[0], ifs);
1439 is->is_sti.tqe_flags |= TQE_RULEBASED;
1440 }
1441 if (fr->fr_age[1] != 0) {
1442 is->is_tqehead[1] =
1443 fr_addtimeoutqueue(&ifs->ifs_ips_utqe,
1444 fr->fr_age[1], ifs);
1445 is->is_sti.tqe_flags |= TQE_RULEBASED;
1446 }
1447 is->is_tag = fr->fr_logtag;
1448
1449 is->is_ifp[(out << 1) + 1] = fr->fr_ifas[1];
1450 is->is_ifp[(1 - out) << 1] = fr->fr_ifas[2];
1451 is->is_ifp[((1 - out) << 1) + 1] = fr->fr_ifas[3];
1452
1453 if (((ifp = fr->fr_ifas[1]) != NULL) &&
1454 (ifp != (void *)-1)) {
1455 COPYIFNAME(ifp, is->is_ifname[(out << 1) + 1], fr->fr_v);
1456 }
1457 if (((ifp = fr->fr_ifas[2]) != NULL) &&
1458 (ifp != (void *)-1)) {
1459 COPYIFNAME(ifp, is->is_ifname[(1 - out) << 1], fr->fr_v);
1460 }
1461 if (((ifp = fr->fr_ifas[3]) != NULL) &&
1462 (ifp != (void *)-1)) {
1463 COPYIFNAME(ifp, is->is_ifname[((1 - out) << 1) + 1], fr->fr_v);
1464 }
1465 }
1466
1467 is->is_ifp[out << 1] = fin->fin_ifp;
1468 if (fin->fin_ifp != NULL) {
1469 COPYIFNAME(fin->fin_ifp, is->is_ifname[out << 1], fin->fin_v);
1470 }
1471
1472 is->is_ref = 1;
1473 is->is_pkts[0] = 0, is->is_bytes[0] = 0;
1474 is->is_pkts[1] = 0, is->is_bytes[1] = 0;
1475 is->is_pkts[2] = 0, is->is_bytes[2] = 0;
1476 is->is_pkts[3] = 0, is->is_bytes[3] = 0;
1477 if ((fin->fin_flx & FI_IGNORE) == 0) {
1478 is->is_pkts[out] = 1;
1479 is->is_bytes[out] = fin->fin_plen;
1480 is->is_flx[out][0] = fin->fin_flx & FI_CMP;
1481 is->is_flx[out][0] &= ~FI_OOW;
1482 }
1483
1484 if (pass & FR_STSTRICT)
1485 is->is_flags |= IS_STRICT;
1486
1487 if (pass & FR_STATESYNC)
1488 is->is_flags |= IS_STATESYNC;
1489
1490 if (flags & (SI_WILDP|SI_WILDA)) {
1491 ATOMIC_INCL(ifs->ifs_ips_stats.iss_wild);
1492 }
1493 is->is_rulen = fin->fin_rule;
1494
1495
1496 if (pass & FR_LOGFIRST)
1497 is->is_pass &= ~(FR_LOGFIRST|FR_LOG);
1498
1499 READ_ENTER(&ifs->ifs_ipf_state);
1500 is->is_me = stsave;
1501
1502 fr_stinsert(is, fin->fin_rev, ifs);
1503
1504 if (fin->fin_p == IPPROTO_TCP) {
1505 /*
1506 * If we're creating state for a starting connection, start the
1507 * timer on it as we'll never see an error if it fails to
1508 * connect.
1509 */
1510 (void) fr_tcp_age(&is->is_sti, fin, ifs->ifs_ips_tqtqb,
1511 is->is_flags);
1512 MUTEX_EXIT(&is->is_lock);
1513 #ifdef IPFILTER_SCAN
1514 if ((is->is_flags & SI_CLONE) == 0)
1515 (void) ipsc_attachis(is);
1516 #endif
1517 } else {
1518 MUTEX_EXIT(&is->is_lock);
1519 }
1520 #ifdef IPFILTER_SYNC
1521 if ((is->is_flags & IS_STATESYNC) && ((is->is_flags & SI_CLONE) == 0))
1522 is->is_sync = ipfsync_new(SMC_STATE, fin, is);
1523 #endif
1524 if (ifs->ifs_ipstate_logging)
1525 ipstate_log(is, ISL_NEW, ifs);
1526
1527 if (IFS_CFWLOG(ifs))
1528 ipf_log_cfwlog(is, ISL_NEW, ifs);
1529
1530 RWLOCK_EXIT(&ifs->ifs_ipf_state);
1531 fin->fin_rev = IP6_NEQ(&is->is_dst, &fin->fin_daddr);
1532 fin->fin_flx |= FI_STATE;
1533 if (fin->fin_flx & FI_FRAG)
1534 (void) fr_newfrag(fin, pass ^ FR_KEEPSTATE);
1535
1536 return is;
1537 }
1538
1539
1540 /* ------------------------------------------------------------------------ */
1541 /* Function: fr_tcpoptions */
1542 /* Returns: int - 1 == packet matches state entry, 0 == it does not */
1543 /* Parameters: fin(I) - pointer to packet information */
1544 /* tcp(I) - pointer to TCP packet header */
1545 /* td(I) - pointer to TCP data held as part of the state */
1546 /* */
1547 /* Look after the TCP header for any options and deal with those that are */
1548 /* present. Record details about those that we recogise. */
1549 /* ------------------------------------------------------------------------ */
1550 static int fr_tcpoptions(fin, tcp, td)
1551 fr_info_t *fin;
1552 tcphdr_t *tcp;
1553 tcpdata_t *td;
1554 {
1555 int off, mlen, ol, i, len, retval;
1556 char buf[64], *s, opt;
1557 mb_t *m = NULL;
1558
1559 len = (TCP_OFF(tcp) << 2);
1560 if (fin->fin_dlen < len)
1561 return 0;
1562 len -= sizeof(*tcp);
1563
1564 off = fin->fin_plen - fin->fin_dlen + sizeof(*tcp) + fin->fin_ipoff;
1565
1566 m = fin->fin_m;
1567 mlen = MSGDSIZE(m) - off;
1568 if (len > mlen) {
1569 len = mlen;
1570 retval = 0;
1571 } else {
1572 retval = 1;
1573 }
1574
1575 COPYDATA(m, off, len, buf);
1576
1577 for (s = buf; len > 0; ) {
1578 opt = *s;
1579 if (opt == TCPOPT_EOL)
1580 break;
1581 else if (opt == TCPOPT_NOP)
1582 ol = 1;
1583 else {
1584 if (len < 2)
1585 break;
1586 ol = (int)*(s + 1);
1587 if (ol < 2 || ol > len)
1588 break;
1589
1590 /*
1591 * Extract the TCP options we are interested in out of
1592 * the header and store them in the the tcpdata struct.
1593 */
1594 switch (opt)
1595 {
1596 case TCPOPT_WINDOW :
1597 if (ol == TCPOLEN_WINDOW) {
1598 i = (int)*(s + 2);
1599 if (i > TCP_WSCALE_MAX)
1600 i = TCP_WSCALE_MAX;
1601 else if (i < 0)
1602 i = 0;
1603 td->td_winscale = i;
1604 td->td_winflags |= TCP_WSCALE_SEEN |
1605 TCP_WSCALE_FIRST;
1606 } else
1607 retval = -1;
1608 break;
1609 case TCPOPT_MAXSEG :
1610 /*
1611 * So, if we wanted to set the TCP MAXSEG,
1612 * it should be done here...
1613 */
1614 if (ol == TCPOLEN_MAXSEG) {
1615 i = (int)*(s + 2);
1616 i <<= 8;
1617 i += (int)*(s + 3);
1618 td->td_maxseg = i;
1619 } else
1620 retval = -1;
1621 break;
1622 case TCPOPT_SACK_PERMITTED :
1623 if (ol == TCPOLEN_SACK_PERMITTED)
1624 td->td_winflags |= TCP_SACK_PERMIT;
1625 else
1626 retval = -1;
1627 break;
1628 }
1629 }
1630 len -= ol;
1631 s += ol;
1632 }
1633 return retval;
1634 }
1635
1636
1637 /* ------------------------------------------------------------------------ */
1638 /* Function: fr_tcpstate */
1639 /* Returns: int - 1 == packet matches state entry, 0 == it does not */
1640 /* Parameters: fin(I) - pointer to packet information */
1641 /* tcp(I) - pointer to TCP packet header */
1642 /* is(I) - pointer to master state structure */
1643 /* */
1644 /* Check to see if a packet with TCP headers fits within the TCP window. */
1645 /* Change timeout depending on whether new packet is a SYN-ACK returning */
1646 /* for a SYN or a RST or FIN which indicate time to close up shop. */
1647 /* ------------------------------------------------------------------------ */
1648 static int fr_tcpstate(fin, tcp, is)
1649 fr_info_t *fin;
1650 tcphdr_t *tcp;
1651 ipstate_t *is;
1652 {
1653 int source, ret = 0, flags;
1654 tcpdata_t *fdata, *tdata;
1655 ipf_stack_t *ifs = fin->fin_ifs;
1656
1657 source = !fin->fin_rev;
1658 if (((is->is_flags & IS_TCPFSM) != 0) && (source == 1) &&
1659 (ntohs(is->is_sport) != fin->fin_data[0]))
1660 source = 0;
1661 fdata = &is->is_tcp.ts_data[!source];
1662 tdata = &is->is_tcp.ts_data[source];
1663
1664 MUTEX_ENTER(&is->is_lock);
1665
1666 /*
1667 * If a SYN packet is received for a connection that is in a half
1668 * closed state, then move its state entry to deletetq. In such case
1669 * the SYN packet will be consequently dropped. This allows new state
1670 * entry to be created with a retransmited SYN packet.
1671 */
1672 if ((tcp->th_flags & TH_OPENING) == TH_SYN) {
1673 if ((is->is_state[source] > IPF_TCPS_ESTABLISHED) &&
1674 (is->is_state[!source] > IPF_TCPS_ESTABLISHED)) {
1675 is->is_state[source] = IPF_TCPS_CLOSED;
1676 is->is_state[!source] = IPF_TCPS_CLOSED;
1677 /*
1678 * Do not update is->is_sti.tqe_die in case state entry
1679 * is already present in deletetq. It prevents state
1680 * entry ttl update by retransmitted SYN packets, which
1681 * may arrive before timer tick kicks off. The SYN
1682 * packet will be dropped again.
1683 */
1684 if (is->is_sti.tqe_ifq != &ifs->ifs_ips_deletetq)
1685 fr_movequeue(&is->is_sti, is->is_sti.tqe_ifq,
1686 &fin->fin_ifs->ifs_ips_deletetq,
1687 fin->fin_ifs);
1688
1689 MUTEX_EXIT(&is->is_lock);
1690 return 0;
1691 }
1692 }
1693
1694 if (fr_tcpinwindow(fin, fdata, tdata, tcp, is->is_flags)) {
1695 #ifdef IPFILTER_SCAN
1696 if (is->is_flags & (IS_SC_CLIENT|IS_SC_SERVER)) {
1697 ipsc_packet(fin, is);
1698 if (FR_ISBLOCK(is->is_pass)) {
1699 MUTEX_EXIT(&is->is_lock);
1700 return 1;
1701 }
1702 }
1703 #endif
1704
1705 /*
1706 * Nearing end of connection, start timeout.
1707 */
1708 ret = fr_tcp_age(&is->is_sti, fin, ifs->ifs_ips_tqtqb,
1709 is->is_flags);
1710 if (ret == 0) {
1711 MUTEX_EXIT(&is->is_lock);
1712 return 0;
1713 }
1714
1715 /*
1716 * set s0's as appropriate. Use syn-ack packet as it
1717 * contains both pieces of required information.
1718 */
1719 /*
1720 * Window scale option is only present in SYN/SYN-ACK packet.
1721 * Compare with ~TH_FIN to mask out T/TCP setups.
1722 */
1723 flags = tcp->th_flags & ~(TH_FIN|TH_ECNALL);
1724 if (flags == (TH_SYN|TH_ACK)) {
1725 is->is_s0[source] = ntohl(tcp->th_ack);
1726 is->is_s0[!source] = ntohl(tcp->th_seq) + 1;
1727 if (TCP_OFF(tcp) > (sizeof (tcphdr_t) >> 2)) {
1728 (void) fr_tcpoptions(fin, tcp, fdata);
1729 }
1730 if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN))
1731 fr_checknewisn(fin, is);
1732 } else if (flags == TH_SYN) {
1733 is->is_s0[source] = ntohl(tcp->th_seq) + 1;
1734 if ((TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2)))
1735 (void) fr_tcpoptions(fin, tcp, fdata);
1736
1737 if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN))
1738 fr_checknewisn(fin, is);
1739
1740 }
1741 ret = 1;
1742 } else
1743 fin->fin_flx |= FI_OOW;
1744 MUTEX_EXIT(&is->is_lock);
1745 return ret;
1746 }
1747
1748
1749 /* ------------------------------------------------------------------------ */
1750 /* Function: fr_checknewisn */
1751 /* Returns: Nil */
1752 /* Parameters: fin(I) - pointer to packet information */
1753 /* is(I) - pointer to master state structure */
1754 /* */
1755 /* Check to see if this TCP connection is expecting and needs a new */
1756 /* sequence number for a particular direction of the connection. */
1757 /* */
1758 /* NOTE: This does not actually change the sequence numbers, only gets new */
1759 /* one ready. */
1760 /* ------------------------------------------------------------------------ */
1761 static void fr_checknewisn(fin, is)
1762 fr_info_t *fin;
1763 ipstate_t *is;
1764 {
1765 u_32_t sumd, old, new;
1766 tcphdr_t *tcp;
1767 int i;
1768
1769 i = fin->fin_rev;
1770 tcp = fin->fin_dp;
1771
1772 if (((i == 0) && !(is->is_flags & IS_ISNSYN)) ||
1773 ((i == 1) && !(is->is_flags & IS_ISNACK))) {
1774 old = ntohl(tcp->th_seq);
1775 new = fr_newisn(fin);
1776 is->is_isninc[i] = new - old;
1777 CALC_SUMD(old, new, sumd);
1778 is->is_sumd[i] = (sumd & 0xffff) + (sumd >> 16);
1779
1780 is->is_flags |= ((i == 0) ? IS_ISNSYN : IS_ISNACK);
1781 }
1782 }
1783
1784
1785 /* ------------------------------------------------------------------------ */
1786 /* Function: fr_tcpinwindow */
1787 /* Returns: int - 1 == packet inside TCP "window", 0 == not inside. */
1788 /* Parameters: fin(I) - pointer to packet information */
1789 /* fdata(I) - pointer to tcp state informatio (forward) */
1790 /* tdata(I) - pointer to tcp state informatio (reverse) */
1791 /* tcp(I) - pointer to TCP packet header */
1792 /* */
1793 /* Given a packet has matched addresses and ports, check to see if it is */
1794 /* within the TCP data window. In a show of generosity, allow packets that */
1795 /* are within the window space behind the current sequence # as well. */
1796 /* ------------------------------------------------------------------------ */
1797 int fr_tcpinwindow(fin, fdata, tdata, tcp, flags)
1798 fr_info_t *fin;
1799 tcpdata_t *fdata, *tdata;
1800 tcphdr_t *tcp;
1801 int flags;
1802 {
1803 tcp_seq seq, ack, end;
1804 int ackskew, tcpflags;
1805 u_32_t win, maxwin;
1806 int dsize, inseq;
1807
1808 /*
1809 * Find difference between last checked packet and this packet.
1810 */
1811 tcpflags = tcp->th_flags;
1812 seq = ntohl(tcp->th_seq);
1813 ack = ntohl(tcp->th_ack);
1814
1815 if (tcpflags & TH_SYN)
1816 win = ntohs(tcp->th_win);
1817 else
1818 win = ntohs(tcp->th_win) << fdata->td_winscale;
1819
1820 /*
1821 * win 0 means the receiving endpoint has closed the window, because it
1822 * has not enough memory to receive data from sender. In such case we
1823 * are pretending window size to be 1 to let TCP probe data through.
1824 * TCP probe data can be either 0 or 1 octet of data, the RFC does not
1825 * state this accurately, so we have to allow 1 octet (win = 1) even if
1826 * the window is closed (win == 0).
1827 */
1828 if (win == 0)
1829 win = 1;
1830
1831 dsize = fin->fin_dlen - (TCP_OFF(tcp) << 2) +
1832 ((tcpflags & TH_SYN) ? 1 : 0) + ((tcpflags & TH_FIN) ? 1 : 0);
1833
1834 /*
1835 * if window scaling is present, the scaling is only allowed
1836 * for windows not in the first SYN packet. In that packet the
1837 * window is 65535 to specify the largest window possible
1838 * for receivers not implementing the window scale option.
1839 * Currently, we do not assume TTCP here. That means that
1840 * if we see a second packet from a host (after the initial
1841 * SYN), we can assume that the receiver of the SYN did
1842 * already send back the SYN/ACK (and thus that we know if
1843 * the receiver also does window scaling)
1844 */
1845 if (!(tcpflags & TH_SYN) && (fdata->td_winflags & TCP_WSCALE_FIRST)) {
1846 fdata->td_winflags &= ~TCP_WSCALE_FIRST;
1847 fdata->td_maxwin = win;
1848 }
1849
1850 end = seq + dsize;
1851
1852 if ((fdata->td_end == 0) &&
1853 (!(flags & IS_TCPFSM) ||
1854 ((tcpflags & TH_OPENING) == TH_OPENING))) {
1855 /*
1856 * Must be a (outgoing) SYN-ACK in reply to a SYN.
1857 */
1858 fdata->td_end = end - 1;
1859 fdata->td_maxwin = 1;
1860 fdata->td_maxend = end + win;
1861 }
1862
1863 if (!(tcpflags & TH_ACK)) { /* Pretend an ack was sent */
1864 ack = tdata->td_end;
1865 } else if (((tcpflags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) &&
1866 (ack == 0)) {
1867 /* gross hack to get around certain broken tcp stacks */
1868 ack = tdata->td_end;
1869 }
1870
1871 maxwin = tdata->td_maxwin;
1872 ackskew = tdata->td_end - ack;
1873
1874 /*
1875 * Strict sequencing only allows in-order delivery.
1876 */
1877 if ((flags & IS_STRICT) != 0) {
1878 if (seq != fdata->td_end) {
1879 DTRACE_PROBE(strict_check);
1880 return 0;
1881 }
1882 }
1883
1884 #define SEQ_GE(a,b) ((int)((a) - (b)) >= 0)
1885 #define SEQ_GT(a,b) ((int)((a) - (b)) > 0)
1886 inseq = 0;
1887 DTRACE_PROBE4(
1888 dyn_params,
1889 int, dsize,
1890 int, ackskew,
1891 int, maxwin,
1892 int, win
1893 );
1894 if (
1895 #if defined(_KERNEL)
1896 /*
1897 * end <-> s + n
1898 * maxend <-> ack + win
1899 * this is upperbound check
1900 */
1901 (SEQ_GE(fdata->td_maxend, end)) &&
1902 /*
1903 * this is lowerbound check
1904 */
1905 (SEQ_GE(seq, fdata->td_end - maxwin)) &&
1906 #endif
1907 /* XXX what about big packets */
1908 #define MAXACKWINDOW 66000
1909 (-ackskew <= (MAXACKWINDOW)) &&
1910 ( ackskew <= (MAXACKWINDOW << fdata->td_winscale))) {
1911 inseq = 1;
1912 /*
1913 * Microsoft Windows will send the next packet to the right of the
1914 * window if SACK is in use.
1915 */
1916 } else if ((seq == fdata->td_maxend) && (ackskew == 0) &&
1917 (fdata->td_winflags & TCP_SACK_PERMIT) &&
1918 (tdata->td_winflags & TCP_SACK_PERMIT)) {
1919 inseq = 1;
1920 /*
1921 * RST ACK with SEQ equal to 0 is sent by some OSes (i.e. Solaris) as a
1922 * response to initial SYN packet, when there is no application
1923 * listeing to on a port, where the SYN packet has came to.
1924 */
1925 } else if ((seq == 0) && (tcpflags == (TH_RST|TH_ACK)) &&
1926 (ackskew >= -1) && (ackskew <= 1)) {
1927 inseq = 1;
1928 } else if (!(flags & IS_TCPFSM)) {
1929
1930 if (!(fdata->td_winflags &
1931 (TCP_WSCALE_SEEN|TCP_WSCALE_FIRST))) {
1932 /*
1933 * No TCPFSM and no window scaling, so make some
1934 * extra guesses.
1935 */
1936 if ((seq == fdata->td_maxend) && (ackskew == 0))
1937 inseq = 1;
1938 else if (SEQ_GE(seq + maxwin, fdata->td_end - maxwin))
1939 inseq = 1;
1940 }
1941 }
1942
1943 if (inseq) {
1944 /* if ackskew < 0 then this should be due to fragmented
1945 * packets. There is no way to know the length of the
1946 * total packet in advance.
1947 * We do know the total length from the fragment cache though.
1948 * Note however that there might be more sessions with
1949 * exactly the same source and destination parameters in the
1950 * state cache (and source and destination is the only stuff
1951 * that is saved in the fragment cache). Note further that
1952 * some TCP connections in the state cache are hashed with
1953 * sport and dport as well which makes it not worthwhile to
1954 * look for them.
1955 * Thus, when ackskew is negative but still seems to belong
1956 * to this session, we bump up the destinations end value.
1957 */
1958 if (ackskew < 0) {
1959 DTRACE_PROBE2(end_update_td,
1960 int, tdata->td_end,
1961 int, ack
1962 );
1963 tdata->td_end = ack;
1964 }
1965
1966 /* update max window seen */
1967 if (fdata->td_maxwin < win) {
1968 DTRACE_PROBE2(win_update_fd,
1969 int, fdata->td_maxwin,
1970 int, win
1971 );
1972 fdata->td_maxwin = win;
1973 }
1974
1975 if (SEQ_GT(end, fdata->td_end)) {
1976 DTRACE_PROBE2(end_update_fd,
1977 int, fdata->td_end,
1978 int, end
1979 );
1980 fdata->td_end = end;
1981 }
1982
1983 if (SEQ_GE(ack + win, tdata->td_maxend)) {
1984 DTRACE_PROBE2(max_end_update_td,
1985 int, tdata->td_maxend,
1986 int, ack + win
1987 );
1988 tdata->td_maxend = ack + win;
1989 }
1990
1991 return 1;
1992 }
1993 fin->fin_flx |= FI_OOW;
1994
1995 #if defined(_KERNEL)
1996 if (!(SEQ_GE(seq, fdata->td_end - maxwin)))
1997 fin->fin_flx |= FI_NEG_OOW;
1998 #endif
1999
2000 return 0;
2001 }
2002
2003
2004 /* ------------------------------------------------------------------------ */
2005 /* Function: fr_stclone */
2006 /* Returns: ipstate_t* - NULL == cloning failed, */
2007 /* else pointer to new state structure */
2008 /* Parameters: fin(I) - pointer to packet information */
2009 /* tcp(I) - pointer to TCP/UDP header */
2010 /* is(I) - pointer to master state structure */
2011 /* */
2012 /* Create a "duplcate" state table entry from the master. */
2013 /* ------------------------------------------------------------------------ */
2014 static ipstate_t *fr_stclone(fin, tcp, is)
2015 fr_info_t *fin;
2016 tcphdr_t *tcp;
2017 ipstate_t *is;
2018 {
2019 ipstate_t *clone;
2020 u_32_t send;
2021 ipf_stack_t *ifs = fin->fin_ifs;
2022
2023 /*
2024 * Trigger automatic call to fr_state_flush() if the
2025 * table has reached capacity specified by hi watermark.
2026 */
2027 if (ST_TAB_WATER_LEVEL(ifs) > ifs->ifs_state_flush_level_hi)
2028 ifs->ifs_fr_state_doflush = 1;
2029
2030 /*
2031 * If automatic flushing did not do its job, and the table
2032 * has filled up, don't try to create a new entry. A NULL
2033 * return will indicate that the cloning has failed.
2034 */
2035 if (ifs->ifs_ips_num >= ifs->ifs_fr_statemax) {
2036 ATOMIC_INCL(ifs->ifs_ips_stats.iss_max);
2037 return NULL;
2038 }
2039
2040 KMALLOC(clone, ipstate_t *);
2041 if (clone == NULL)
2042 return NULL;
2043 bcopy((char *)is, (char *)clone, sizeof(*clone));
2044
2045 MUTEX_NUKE(&clone->is_lock);
2046
2047 clone->is_die = ONE_DAY + ifs->ifs_fr_ticks;
2048 clone->is_state[0] = 0;
2049 clone->is_state[1] = 0;
2050 send = ntohl(tcp->th_seq) + fin->fin_dlen - (TCP_OFF(tcp) << 2) +
2051 ((tcp->th_flags & TH_SYN) ? 1 : 0) +
2052 ((tcp->th_flags & TH_FIN) ? 1 : 0);
2053
2054 if (fin->fin_rev == 1) {
2055 clone->is_dend = send;
2056 clone->is_maxdend = send;
2057 clone->is_send = 0;
2058 clone->is_maxswin = 1;
2059 clone->is_maxdwin = ntohs(tcp->th_win);
2060 if (clone->is_maxdwin == 0)
2061 clone->is_maxdwin = 1;
2062 } else {
2063 clone->is_send = send;
2064 clone->is_maxsend = send;
2065 clone->is_dend = 0;
2066 clone->is_maxdwin = 1;
2067 clone->is_maxswin = ntohs(tcp->th_win);
2068 if (clone->is_maxswin == 0)
2069 clone->is_maxswin = 1;
2070 }
2071
2072 clone->is_flags &= ~SI_CLONE;
2073 clone->is_flags |= SI_CLONED;
2074 fr_stinsert(clone, fin->fin_rev, ifs);
2075 clone->is_ref = 1;
2076 if (clone->is_p == IPPROTO_TCP) {
2077 (void) fr_tcp_age(&clone->is_sti, fin, ifs->ifs_ips_tqtqb,
2078 clone->is_flags);
2079 }
2080 MUTEX_EXIT(&clone->is_lock);
2081 #ifdef IPFILTER_SCAN
2082 (void) ipsc_attachis(is);
2083 #endif
2084 #ifdef IPFILTER_SYNC
2085 if (is->is_flags & IS_STATESYNC)
2086 clone->is_sync = ipfsync_new(SMC_STATE, fin, clone);
2087 #endif
2088 return clone;
2089 }
2090
2091
2092 /* ------------------------------------------------------------------------ */
2093 /* Function: fr_matchsrcdst */
2094 /* Returns: Nil */
2095 /* Parameters: fin(I) - pointer to packet information */
2096 /* is(I) - pointer to state structure */
2097 /* src(I) - pointer to source address */
2098 /* dst(I) - pointer to destination address */
2099 /* tcp(I) - pointer to TCP/UDP header */
2100 /* */
2101 /* Match a state table entry against an IP packet. The logic below is that */
2102 /* ret gets set to one if the match succeeds, else remains 0. If it is */
2103 /* still 0 after the test. no match. */
2104 /* ------------------------------------------------------------------------ */
2105 static ipstate_t *fr_matchsrcdst(fin, is, src, dst, tcp, cmask)
2106 fr_info_t *fin;
2107 ipstate_t *is;
2108 i6addr_t *src, *dst;
2109 tcphdr_t *tcp;
2110 u_32_t cmask;
2111 {
2112 int ret = 0, rev, out, flags, flx = 0, idx;
2113 u_short sp, dp;
2114 u_32_t cflx;
2115 void *ifp;
2116 ipf_stack_t *ifs = fin->fin_ifs;
2117
2118 rev = IP6_NEQ(&is->is_dst, dst);
2119 ifp = fin->fin_ifp;
2120 out = fin->fin_out;
2121 flags = is->is_flags;
2122 sp = 0;
2123 dp = 0;
2124
2125 if (tcp != NULL) {
2126 sp = htons(fin->fin_sport);
2127 dp = ntohs(fin->fin_dport);
2128 }
2129 if (!rev) {
2130 if (tcp != NULL) {
2131 if (!(flags & SI_W_SPORT) && (sp != is->is_sport))
2132 rev = 1;
2133 else if (!(flags & SI_W_DPORT) && (dp != is->is_dport))
2134 rev = 1;
2135 }
2136 }
2137
2138 idx = (out << 1) + rev;
2139
2140 /*
2141 * If the interface for this 'direction' is set, make sure it matches.
2142 * An interface name that is not set matches any, as does a name of *.
2143 */
2144 if ((is->is_ifp[idx] == NULL &&
2145 (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '*')) ||
2146 is->is_ifp[idx] == ifp)
2147 ret = 1;
2148
2149 if (ret == 0) {
2150 DTRACE_PROBE(no_match_on_iface);
2151 return NULL;
2152 }
2153 ret = 0;
2154
2155 /*
2156 * Match addresses and ports.
2157 */
2158 if (rev == 0) {
2159 if ((IP6_EQ(&is->is_dst, dst) || (flags & SI_W_DADDR)) &&
2160 (IP6_EQ(&is->is_src, src) || (flags & SI_W_SADDR))) {
2161 if (tcp) {
2162 if ((sp == is->is_sport || flags & SI_W_SPORT)&&
2163 (dp == is->is_dport || flags & SI_W_DPORT))
2164 ret = 1;
2165 } else {
2166 ret = 1;
2167 }
2168 }
2169 } else {
2170 if ((IP6_EQ(&is->is_dst, src) || (flags & SI_W_DADDR)) &&
2171 (IP6_EQ(&is->is_src, dst) || (flags & SI_W_SADDR))) {
2172 if (tcp) {
2173 if ((dp == is->is_sport || flags & SI_W_SPORT)&&
2174 (sp == is->is_dport || flags & SI_W_DPORT))
2175 ret = 1;
2176 } else {
2177 ret = 1;
2178 }
2179 }
2180 }
2181
2182 if (ret == 0) {
2183 DTRACE_PROBE(no_match_on_addrs);
2184 return NULL;
2185 }
2186 /*
2187 * Whether or not this should be here, is questionable, but the aim
2188 * is to get this out of the main line.
2189 */
2190 if (tcp == NULL)
2191 flags = is->is_flags & ~(SI_WILDP|SI_NEWFR|SI_CLONE|SI_CLONED);
2192
2193 /*
2194 * Only one of the source or destination address can be flaged as a
2195 * wildcard. Fill in the missing address, if set.
2196 * For IPv6, if the address being copied in is multicast, then
2197 * don't reset the wild flag - multicast causes it to be set in the
2198 * first place!
2199 */
2200 if ((flags & (SI_W_SADDR|SI_W_DADDR))) {
2201 fr_ip_t *fi = &fin->fin_fi;
2202
2203 if ((flags & SI_W_SADDR) != 0) {
2204 if (rev == 0) {
2205 #ifdef USE_INET6
2206 if (is->is_v == 6 &&
2207 IN6_IS_ADDR_MULTICAST(&fi->fi_src.in6))
2208 /*EMPTY*/;
2209 else
2210 #endif
2211 {
2212 is->is_src = fi->fi_src;
2213 is->is_flags &= ~SI_W_SADDR;
2214 }
2215 } else {
2216 #ifdef USE_INET6
2217 if (is->is_v == 6 &&
2218 IN6_IS_ADDR_MULTICAST(&fi->fi_dst.in6))
2219 /*EMPTY*/;
2220 else
2221 #endif
2222 {
2223 is->is_src = fi->fi_dst;
2224 is->is_flags &= ~SI_W_SADDR;
2225 }
2226 }
2227 } else if ((flags & SI_W_DADDR) != 0) {
2228 if (rev == 0) {
2229 #ifdef USE_INET6
2230 if (is->is_v == 6 &&
2231 IN6_IS_ADDR_MULTICAST(&fi->fi_dst.in6))
2232 /*EMPTY*/;
2233 else
2234 #endif
2235 {
2236 is->is_dst = fi->fi_dst;
2237 is->is_flags &= ~SI_W_DADDR;
2238 }
2239 } else {
2240 #ifdef USE_INET6
2241 if (is->is_v == 6 &&
2242 IN6_IS_ADDR_MULTICAST(&fi->fi_src.in6))
2243 /*EMPTY*/;
2244 else
2245 #endif
2246 {
2247 is->is_dst = fi->fi_src;
2248 is->is_flags &= ~SI_W_DADDR;
2249 }
2250 }
2251 }
2252 if ((is->is_flags & (SI_WILDA|SI_WILDP)) == 0) {
2253 ATOMIC_DECL(ifs->ifs_ips_stats.iss_wild);
2254 }
2255 }
2256
2257 flx = fin->fin_flx & cmask;
2258 cflx = is->is_flx[out][rev];
2259
2260 /*
2261 * Match up any flags set from IP options.
2262 */
2263 if ((cflx && (flx != (cflx & cmask))) ||
2264 ((fin->fin_optmsk & is->is_optmsk[rev]) != is->is_opt[rev]) ||
2265 ((fin->fin_secmsk & is->is_secmsk) != is->is_sec) ||
2266 ((fin->fin_auth & is->is_authmsk) != is->is_auth)) {
2267 DTRACE_PROBE4(no_match_on_flags,
2268 int, (cflx && (flx != (cflx & cmask))),
2269 int,
2270 ((fin->fin_optmsk & is->is_optmsk[rev]) != is->is_opt[rev]),
2271 int, ((fin->fin_secmsk & is->is_secmsk) != is->is_sec),
2272 int, ((fin->fin_auth & is->is_authmsk) != is->is_auth)
2273 );
2274 return NULL;
2275 }
2276 /*
2277 * Only one of the source or destination port can be flagged as a
2278 * wildcard. When filling it in, fill in a copy of the matched entry
2279 * if it has the cloning flag set.
2280 */
2281 if ((fin->fin_flx & FI_IGNORE) != 0) {
2282 fin->fin_rev = rev;
2283 return is;
2284 }
2285
2286 if ((flags & (SI_W_SPORT|SI_W_DPORT))) {
2287 if ((flags & SI_CLONE) != 0) {
2288 ipstate_t *clone;
2289
2290 clone = fr_stclone(fin, tcp, is);
2291 if (clone == NULL)
2292 return NULL;
2293 is = clone;
2294 } else {
2295 ATOMIC_DECL(ifs->ifs_ips_stats.iss_wild);
2296 }
2297
2298 if ((flags & SI_W_SPORT) != 0) {
2299 if (rev == 0) {
2300 is->is_sport = sp;
2301 is->is_send = ntohl(tcp->th_seq);
2302 } else {
2303 is->is_sport = dp;
2304 is->is_send = ntohl(tcp->th_ack);
2305 }
2306 is->is_maxsend = is->is_send + 1;
2307 } else if ((flags & SI_W_DPORT) != 0) {
2308 if (rev == 0) {
2309 is->is_dport = dp;
2310 is->is_dend = ntohl(tcp->th_ack);
2311 } else {
2312 is->is_dport = sp;
2313 is->is_dend = ntohl(tcp->th_seq);
2314 }
2315 is->is_maxdend = is->is_dend + 1;
2316 }
2317 is->is_flags &= ~(SI_W_SPORT|SI_W_DPORT);
2318 if ((flags & SI_CLONED) && ifs->ifs_ipstate_logging)
2319 ipstate_log(is, ISL_CLONE, ifs);
2320 if ((flags & SI_CLONED) && IFS_CFWLOG(ifs))
2321 ipf_log_cfwlog(is, ISL_CLONE, ifs);
2322 }
2323
2324 ret = -1;
2325
2326 if (is->is_flx[out][rev] == 0) {
2327 is->is_flx[out][rev] = flx;
2328 /*
2329 * If we are dealing with the first packet coming in reverse
2330 * direction (sent by peer), then we have to set options into
2331 * state.
2332 */
2333 if (rev == 1 && is->is_optmsk[1] == 0x0) {
2334 is->is_optmsk[1] = 0xffffffff;
2335 is->is_opt[1] = fin->fin_optmsk;
2336 DTRACE_PROBE(set_rev_opts);
2337 }
2338 if (is->is_v == 6) {
2339 is->is_opt[rev] &= ~0x8;
2340 is->is_optmsk[rev] &= ~0x8;
2341 }
2342 }
2343
2344 /*
2345 * Check if the interface name for this "direction" is set and if not,
2346 * fill it in.
2347 */
2348 if (is->is_ifp[idx] == NULL &&
2349 (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '*')) {
2350 is->is_ifp[idx] = ifp;
2351 COPYIFNAME(ifp, is->is_ifname[idx], fin->fin_v);
2352 }
2353 fin->fin_rev = rev;
2354 return is;
2355 }
2356
2357
2358 /* ------------------------------------------------------------------------ */
2359 /* Function: fr_checkicmpmatchingstate */
2360 /* Returns: Nil */
2361 /* Parameters: fin(I) - pointer to packet information */
2362 /* */
2363 /* If we've got an ICMP error message, using the information stored in the */
2364 /* ICMP packet, look for a matching state table entry. */
2365 /* */
2366 /* If we return NULL then no lock on ipf_state is held. */
2367 /* If we return non-null then a read-lock on ipf_state is held. */
2368 /* ------------------------------------------------------------------------ */
2369 static ipstate_t *fr_checkicmpmatchingstate(fin)
2370 fr_info_t *fin;
2371 {
2372 ipstate_t *is, **isp;
2373 u_short sport, dport;
2374 u_char pr;
2375 int backward, i, oi;
2376 i6addr_t dst, src;
2377 struct icmp *ic;
2378 u_short savelen;
2379 icmphdr_t *icmp;
2380 fr_info_t ofin;
2381 tcphdr_t *tcp;
2382 int len;
2383 ip_t *oip;
2384 u_int hv;
2385 ipf_stack_t *ifs = fin->fin_ifs;
2386
2387 /*
2388 * Does it at least have the return (basic) IP header ?
2389 * Is it an actual recognised ICMP error type?
2390 * Only a basic IP header (no options) should be with
2391 * an ICMP error header.
2392 */
2393 if ((fin->fin_v != 4) || (fin->fin_hlen != sizeof(ip_t)) ||
2394 (fin->fin_plen < ICMPERR_MINPKTLEN) ||
2395 !(fin->fin_flx & FI_ICMPERR))
2396 return NULL;
2397 ic = fin->fin_dp;
2398
2399 oip = (ip_t *)((char *)ic + ICMPERR_ICMPHLEN);
2400 /*
2401 * Check if the at least the old IP header (with options) and
2402 * 8 bytes of payload is present.
2403 */
2404 if (fin->fin_plen < ICMPERR_MAXPKTLEN + ((IP_HL(oip) - 5) << 2))
2405 return NULL;
2406
2407 /*
2408 * Sanity Checks.
2409 */
2410 len = fin->fin_dlen - ICMPERR_ICMPHLEN;
2411 if ((len <= 0) || ((IP_HL(oip) << 2) > len))
2412 return NULL;
2413
2414 /*
2415 * Is the buffer big enough for all of it ? It's the size of the IP
2416 * header claimed in the encapsulated part which is of concern. It
2417 * may be too big to be in this buffer but not so big that it's
2418 * outside the ICMP packet, leading to TCP deref's causing problems.
2419 * This is possible because we don't know how big oip_hl is when we
2420 * do the pullup early in fr_check() and thus can't guarantee it is
2421 * all here now.
2422 */
2423 #ifdef _KERNEL
2424 {
2425 mb_t *m;
2426
2427 m = fin->fin_m;
2428 # if defined(MENTAT)
2429 if ((char *)oip + len > (char *)m->b_wptr)
2430 return NULL;
2431 # else
2432 if ((char *)oip + len > (char *)fin->fin_ip + m->m_len)
2433 return NULL;
2434 # endif
2435 }
2436 #endif
2437 bcopy((char *)fin, (char *)&ofin, sizeof(*fin));
2438
2439 /*
2440 * in the IPv4 case we must zero the i6addr union otherwise
2441 * the IP6_EQ and IP6_NEQ macros produce the wrong results because
2442 * of the 'junk' in the unused part of the union
2443 */
2444 bzero((char *)&src, sizeof(src));
2445 bzero((char *)&dst, sizeof(dst));
2446
2447 /*
2448 * we make an fin entry to be able to feed it to
2449 * matchsrcdst note that not all fields are encessary
2450 * but this is the cleanest way. Note further we fill
2451 * in fin_mp such that if someone uses it we'll get
2452 * a kernel panic. fr_matchsrcdst does not use this.
2453 *
2454 * watch out here, as ip is in host order and oip in network
2455 * order. Any change we make must be undone afterwards, like
2456 * oip->ip_off - it is still in network byte order so fix it.
2457 */
2458 savelen = oip->ip_len;
2459 oip->ip_len = len;
2460 oip->ip_off = ntohs(oip->ip_off);
2461
2462 ofin.fin_flx = FI_NOCKSUM;
2463 ofin.fin_v = 4;
2464 ofin.fin_ip = oip;
2465 ofin.fin_m = NULL; /* if dereferenced, panic XXX */
2466 ofin.fin_mp = NULL; /* if dereferenced, panic XXX */
2467 ofin.fin_plen = fin->fin_dlen - ICMPERR_ICMPHLEN;
2468 (void) fr_makefrip(IP_HL(oip) << 2, oip, &ofin);
2469 ofin.fin_ifp = fin->fin_ifp;
2470 ofin.fin_out = !fin->fin_out;
2471 /*
2472 * Reset the short and bad flag here because in fr_matchsrcdst()
2473 * the flags for the current packet (fin_flx) are compared against
2474 * those for the existing session.
2475 */
2476 ofin.fin_flx &= ~(FI_BAD|FI_SHORT);
2477
2478 /*
2479 * Put old values of ip_len and ip_off back as we don't know
2480 * if we have to forward the packet (or process it again.
2481 */
2482 oip->ip_len = savelen;
2483 oip->ip_off = htons(oip->ip_off);
2484
2485 switch (oip->ip_p)
2486 {
2487 case IPPROTO_ICMP :
2488 /*
2489 * an ICMP error can only be generated as a result of an
2490 * ICMP query, not as the response on an ICMP error
2491 *
2492 * XXX theoretically ICMP_ECHOREP and the other reply's are
2493 * ICMP query's as well, but adding them here seems strange XXX
2494 */
2495 if ((ofin.fin_flx & FI_ICMPERR) != 0)
2496 return NULL;
2497
2498 /*
2499 * perform a lookup of the ICMP packet in the state table
2500 */
2501 icmp = (icmphdr_t *)((char *)oip + (IP_HL(oip) << 2));
2502 hv = (pr = oip->ip_p);
2503 src.in4 = oip->ip_src;
2504 hv += src.in4.s_addr;
2505 dst.in4 = oip->ip_dst;
2506 hv += dst.in4.s_addr;
2507 hv += icmp->icmp_id;
2508 hv = DOUBLE_HASH(hv, ifs);
2509
2510 READ_ENTER(&ifs->ifs_ipf_state);
2511 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) {
2512 isp = &is->is_hnext;
2513 if ((is->is_p != pr) || (is->is_v != 4))
2514 continue;
2515 if (is->is_pass & FR_NOICMPERR)
2516 continue;
2517 is = fr_matchsrcdst(&ofin, is, &src, &dst,
2518 NULL, FI_ICMPCMP);
2519 if (is != NULL) {
2520 if ((is->is_pass & FR_NOICMPERR) != 0) {
2521 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2522 return NULL;
2523 }
2524 /*
2525 * i : the index of this packet (the icmp
2526 * unreachable)
2527 * oi : the index of the original packet found
2528 * in the icmp header (i.e. the packet
2529 * causing this icmp)
2530 * backward : original packet was backward
2531 * compared to the state
2532 */
2533 backward = IP6_NEQ(&is->is_src, &src);
2534 fin->fin_rev = !backward;
2535 i = (!backward << 1) + fin->fin_out;
2536 oi = (backward << 1) + ofin.fin_out;
2537 if (is->is_icmppkts[i] > is->is_pkts[oi])
2538 continue;
2539 ifs->ifs_ips_stats.iss_hits++;
2540 is->is_icmppkts[i]++;
2541 return is;
2542 }
2543 }
2544 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2545 return NULL;
2546 case IPPROTO_TCP :
2547 case IPPROTO_UDP :
2548 break;
2549 default :
2550 return NULL;
2551 }
2552
2553 tcp = (tcphdr_t *)((char *)oip + (IP_HL(oip) << 2));
2554 dport = tcp->th_dport;
2555 sport = tcp->th_sport;
2556
2557 hv = (pr = oip->ip_p);
2558 src.in4 = oip->ip_src;
2559 hv += src.in4.s_addr;
2560 dst.in4 = oip->ip_dst;
2561 hv += dst.in4.s_addr;
2562 hv += dport;
2563 hv += sport;
2564 hv = DOUBLE_HASH(hv, ifs);
2565
2566 READ_ENTER(&ifs->ifs_ipf_state);
2567 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) {
2568 isp = &is->is_hnext;
2569 /*
2570 * Only allow this icmp though if the
2571 * encapsulated packet was allowed through the
2572 * other way around. Note that the minimal amount
2573 * of info present does not allow for checking against
2574 * tcp internals such as seq and ack numbers. Only the
2575 * ports are known to be present and can be even if the
2576 * short flag is set.
2577 */
2578 if ((is->is_p == pr) && (is->is_v == 4) &&
2579 (is = fr_matchsrcdst(&ofin, is, &src, &dst,
2580 tcp, FI_ICMPCMP))) {
2581 /*
2582 * i : the index of this packet (the icmp unreachable)
2583 * oi : the index of the original packet found in the
2584 * icmp header (i.e. the packet causing this icmp)
2585 * backward : original packet was backward compared to
2586 * the state
2587 */
2588 backward = IP6_NEQ(&is->is_src, &src);
2589 fin->fin_rev = !backward;
2590 i = (!backward << 1) + fin->fin_out;
2591 oi = (backward << 1) + ofin.fin_out;
2592
2593 if (((is->is_pass & FR_NOICMPERR) != 0) ||
2594 (is->is_icmppkts[i] > is->is_pkts[oi]))
2595 break;
2596 ifs->ifs_ips_stats.iss_hits++;
2597 is->is_icmppkts[i]++;
2598 /*
2599 * we deliberately do not touch the timeouts
2600 * for the accompanying state table entry.
2601 * It remains to be seen if that is correct. XXX
2602 */
2603 return is;
2604 }
2605 }
2606 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2607 return NULL;
2608 }
2609
2610
2611 /* ------------------------------------------------------------------------ */
2612 /* Function: fr_ipsmove */
2613 /* Returns: Nil */
2614 /* Parameters: is(I) - pointer to state table entry */
2615 /* hv(I) - new hash value for state table entry */
2616 /* Write Locks: ipf_state */
2617 /* */
2618 /* Move a state entry from one position in the hash table to another. */
2619 /* ------------------------------------------------------------------------ */
2620 static void fr_ipsmove(is, hv, ifs)
2621 ipstate_t *is;
2622 u_int hv;
2623 ipf_stack_t *ifs;
2624 {
2625 ipstate_t **isp;
2626 u_int hvm;
2627
2628 ASSERT(rw_read_locked(&ifs->ifs_ipf_state.ipf_lk) == 0);
2629
2630 hvm = is->is_hv;
2631 /*
2632 * Remove the hash from the old location...
2633 */
2634 isp = is->is_phnext;
2635 if (is->is_hnext)
2636 is->is_hnext->is_phnext = isp;
2637 *isp = is->is_hnext;
2638 if (ifs->ifs_ips_table[hvm] == NULL)
2639 ifs->ifs_ips_stats.iss_inuse--;
2640 ifs->ifs_ips_stats.iss_bucketlen[hvm]--;
2641
2642 /*
2643 * ...and put the hash in the new one.
2644 */
2645 hvm = DOUBLE_HASH(hv, ifs);
2646 is->is_hv = hvm;
2647 isp = &ifs->ifs_ips_table[hvm];
2648 if (*isp)
2649 (*isp)->is_phnext = &is->is_hnext;
2650 else
2651 ifs->ifs_ips_stats.iss_inuse++;
2652 ifs->ifs_ips_stats.iss_bucketlen[hvm]++;
2653 is->is_phnext = isp;
2654 is->is_hnext = *isp;
2655 *isp = is;
2656 }
2657
2658
2659 /* ------------------------------------------------------------------------ */
2660 /* Function: fr_stlookup */
2661 /* Returns: ipstate_t* - NULL == no matching state found, */
2662 /* else pointer to state information is returned */
2663 /* Parameters: fin(I) - pointer to packet information */
2664 /* tcp(I) - pointer to TCP/UDP header. */
2665 /* */
2666 /* Search the state table for a matching entry to the packet described by */
2667 /* the contents of *fin. */
2668 /* */
2669 /* If we return NULL then no lock on ipf_state is held. */
2670 /* If we return non-null then a read-lock on ipf_state is held. */
2671 /* ------------------------------------------------------------------------ */
2672 ipstate_t *fr_stlookup(fin, tcp, ifqp)
2673 fr_info_t *fin;
2674 tcphdr_t *tcp;
2675 ipftq_t **ifqp;
2676 {
2677 u_int hv, hvm, pr, v, tryagain;
2678 ipstate_t *is, **isp;
2679 u_short dport, sport;
2680 i6addr_t src, dst;
2681 struct icmp *ic;
2682 ipftq_t *ifq;
2683 int oow;
2684 ipf_stack_t *ifs = fin->fin_ifs;
2685
2686 is = NULL;
2687 ifq = NULL;
2688 tcp = fin->fin_dp;
2689 ic = (struct icmp *)tcp;
2690 hv = (pr = fin->fin_fi.fi_p);
2691 src = fin->fin_fi.fi_src;
2692 dst = fin->fin_fi.fi_dst;
2693 hv += src.in4.s_addr;
2694 hv += dst.in4.s_addr;
2695
2696 v = fin->fin_fi.fi_v;
2697 #ifdef USE_INET6
2698 if (v == 6) {
2699 hv += fin->fin_fi.fi_src.i6[1];
2700 hv += fin->fin_fi.fi_src.i6[2];
2701 hv += fin->fin_fi.fi_src.i6[3];
2702
2703 if ((fin->fin_p == IPPROTO_ICMPV6) &&
2704 IN6_IS_ADDR_MULTICAST(&fin->fin_fi.fi_dst.in6)) {
2705 hv -= dst.in4.s_addr;
2706 } else {
2707 hv += fin->fin_fi.fi_dst.i6[1];
2708 hv += fin->fin_fi.fi_dst.i6[2];
2709 hv += fin->fin_fi.fi_dst.i6[3];
2710 }
2711 }
2712 #endif
2713 if ((v == 4) &&
2714 (fin->fin_flx & (FI_MULTICAST|FI_BROADCAST|FI_MBCAST))) {
2715 if (fin->fin_out == 0) {
2716 hv -= src.in4.s_addr;
2717 } else {
2718 hv -= dst.in4.s_addr;
2719 }
2720 }
2721
2722 /*
2723 * Search the hash table for matching packet header info.
2724 */
2725 switch (pr)
2726 {
2727 #ifdef USE_INET6
2728 case IPPROTO_ICMPV6 :
2729 tryagain = 0;
2730 if (v == 6) {
2731 if ((ic->icmp_type == ICMP6_ECHO_REQUEST) ||
2732 (ic->icmp_type == ICMP6_ECHO_REPLY)) {
2733 hv += ic->icmp_id;
2734 }
2735 }
2736 READ_ENTER(&ifs->ifs_ipf_state);
2737 icmp6again:
2738 hvm = DOUBLE_HASH(hv, ifs);
2739 for (isp = &ifs->ifs_ips_table[hvm]; ((is = *isp) != NULL); ) {
2740 isp = &is->is_hnext;
2741 if ((is->is_p != pr) || (is->is_v != v))
2742 continue;
2743 is = fr_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP);
2744 if (is != NULL &&
2745 fr_matchicmpqueryreply(v, &is->is_icmp,
2746 ic, fin->fin_rev)) {
2747 if (fin->fin_rev)
2748 ifq = &ifs->ifs_ips_icmpacktq;
2749 else
2750 ifq = &ifs->ifs_ips_icmptq;
2751 break;
2752 }
2753 }
2754
2755 if (is != NULL) {
2756 if ((tryagain != 0) && !(is->is_flags & SI_W_DADDR)) {
2757 hv += fin->fin_fi.fi_src.i6[0];
2758 hv += fin->fin_fi.fi_src.i6[1];
2759 hv += fin->fin_fi.fi_src.i6[2];
2760 hv += fin->fin_fi.fi_src.i6[3];
2761 fr_ipsmove(is, hv, ifs);
2762 MUTEX_DOWNGRADE(&ifs->ifs_ipf_state);
2763 }
2764 break;
2765 }
2766 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2767
2768 /*
2769 * No matching icmp state entry. Perhaps this is a
2770 * response to another state entry.
2771 *
2772 * XXX With some ICMP6 packets, the "other" address is already
2773 * in the packet, after the ICMP6 header, and this could be
2774 * used in place of the multicast address. However, taking
2775 * advantage of this requires some significant code changes
2776 * to handle the specific types where that is the case.
2777 */
2778 if ((ifs->ifs_ips_stats.iss_wild != 0) && (v == 6) && (tryagain == 0) &&
2779 !IN6_IS_ADDR_MULTICAST(&fin->fin_fi.fi_src.in6)) {
2780 hv -= fin->fin_fi.fi_src.i6[0];
2781 hv -= fin->fin_fi.fi_src.i6[1];
2782 hv -= fin->fin_fi.fi_src.i6[2];
2783 hv -= fin->fin_fi.fi_src.i6[3];
2784 tryagain = 1;
2785 WRITE_ENTER(&ifs->ifs_ipf_state);
2786 goto icmp6again;
2787 }
2788
2789 is = fr_checkicmp6matchingstate(fin);
2790 if (is != NULL)
2791 return is;
2792 break;
2793 #endif
2794
2795 case IPPROTO_ICMP :
2796 if (v == 4) {
2797 hv += ic->icmp_id;
2798 }
2799 hv = DOUBLE_HASH(hv, ifs);
2800 READ_ENTER(&ifs->ifs_ipf_state);
2801 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) {
2802 isp = &is->is_hnext;
2803 if ((is->is_p != pr) || (is->is_v != v))
2804 continue;
2805 is = fr_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP);
2806 if (is != NULL &&
2807 fr_matchicmpqueryreply(v, &is->is_icmp,
2808 ic, fin->fin_rev)) {
2809 if (fin->fin_rev)
2810 ifq = &ifs->ifs_ips_icmpacktq;
2811 else
2812 ifq = &ifs->ifs_ips_icmptq;
2813 break;
2814 }
2815 }
2816 if (is == NULL) {
2817 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2818 }
2819 break;
2820
2821 case IPPROTO_TCP :
2822 case IPPROTO_UDP :
2823 ifqp = NULL;
2824 sport = htons(fin->fin_data[0]);
2825 hv += sport;
2826 dport = htons(fin->fin_data[1]);
2827 hv += dport;
2828 oow = 0;
2829 tryagain = 0;
2830 READ_ENTER(&ifs->ifs_ipf_state);
2831 retry_tcpudp:
2832 hvm = DOUBLE_HASH(hv, ifs);
2833 for (isp = &ifs->ifs_ips_table[hvm]; ((is = *isp) != NULL); ) {
2834 isp = &is->is_hnext;
2835 if ((is->is_p != pr) || (is->is_v != v))
2836 continue;
2837 fin->fin_flx &= ~FI_OOW;
2838 is = fr_matchsrcdst(fin, is, &src, &dst, tcp, FI_CMP);
2839 if (is != NULL) {
2840 if (pr == IPPROTO_TCP) {
2841 if (!fr_tcpstate(fin, tcp, is)) {
2842 oow |= fin->fin_flx & FI_OOW;
2843 continue;
2844 }
2845 }
2846 break;
2847 }
2848 }
2849 if (is != NULL) {
2850 if (tryagain &&
2851 !(is->is_flags & (SI_CLONE|SI_WILDP|SI_WILDA))) {
2852 hv += dport;
2853 hv += sport;
2854 fr_ipsmove(is, hv, ifs);
2855 MUTEX_DOWNGRADE(&ifs->ifs_ipf_state);
2856 }
2857 break;
2858 }
2859 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2860
2861 if (ifs->ifs_ips_stats.iss_wild) {
2862 if (tryagain == 0) {
2863 hv -= dport;
2864 hv -= sport;
2865 } else if (tryagain == 1) {
2866 hv = fin->fin_fi.fi_p;
2867 /*
2868 * If we try to pretend this is a reply to a
2869 * multicast/broadcast packet then we need to
2870 * exclude part of the address from the hash
2871 * calculation.
2872 */
2873 if (fin->fin_out == 0) {
2874 hv += src.in4.s_addr;
2875 } else {
2876 hv += dst.in4.s_addr;
2877 }
2878 hv += dport;
2879 hv += sport;
2880 }
2881 tryagain++;
2882 if (tryagain <= 2) {
2883 WRITE_ENTER(&ifs->ifs_ipf_state);
2884 goto retry_tcpudp;
2885 }
2886 }
2887 fin->fin_flx |= oow;
2888 break;
2889
2890 #if 0
2891 case IPPROTO_GRE :
2892 gre = fin->fin_dp;
2893 if (GRE_REV(gre->gr_flags) == 1) {
2894 hv += gre->gr_call;
2895 }
2896 /* FALLTHROUGH */
2897 #endif
2898 default :
2899 ifqp = NULL;
2900 hvm = DOUBLE_HASH(hv, ifs);
2901 READ_ENTER(&ifs->ifs_ipf_state);
2902 for (isp = &ifs->ifs_ips_table[hvm]; ((is = *isp) != NULL); ) {
2903 isp = &is->is_hnext;
2904 if ((is->is_p != pr) || (is->is_v != v))
2905 continue;
2906 is = fr_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP);
2907 if (is != NULL) {
2908 ifq = &ifs->ifs_ips_iptq;
2909 break;
2910 }
2911 }
2912 if (is == NULL) {
2913 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2914 }
2915 break;
2916 }
2917
2918 if ((is != NULL) && ((is->is_sti.tqe_flags & TQE_RULEBASED) != 0) &&
2919 (is->is_tqehead[fin->fin_rev] != NULL))
2920 ifq = is->is_tqehead[fin->fin_rev];
2921 if (ifq != NULL && ifqp != NULL)
2922 *ifqp = ifq;
2923 return is;
2924 }
2925
2926
2927 /* ------------------------------------------------------------------------ */
2928 /* Function: fr_updatestate */
2929 /* Returns: Nil */
2930 /* Parameters: fin(I) - pointer to packet information */
2931 /* is(I) - pointer to state table entry */
2932 /* Read Locks: ipf_state */
2933 /* */
2934 /* Updates packet and byte counters for a newly received packet. Seeds the */
2935 /* fragment cache with a new entry as required. */
2936 /* ------------------------------------------------------------------------ */
2937 void fr_updatestate(fin, is, ifq)
2938 fr_info_t *fin;
2939 ipstate_t *is;
2940 ipftq_t *ifq;
2941 {
2942 ipftqent_t *tqe;
2943 int i, pass;
2944 ipf_stack_t *ifs = fin->fin_ifs;
2945
2946 i = (fin->fin_rev << 1) + fin->fin_out;
2947
2948 /*
2949 * For TCP packets, ifq == NULL. For all others, check if this new
2950 * queue is different to the last one it was on and move it if so.
2951 */
2952 tqe = &is->is_sti;
2953 MUTEX_ENTER(&is->is_lock);
2954 if ((tqe->tqe_flags & TQE_RULEBASED) != 0)
2955 ifq = is->is_tqehead[fin->fin_rev];
2956
2957 if (ifq != NULL)
2958 fr_movequeue(tqe, tqe->tqe_ifq, ifq, ifs);
2959
2960 is->is_pkts[i]++;
2961 fin->fin_pktnum = is->is_pkts[i] + is->is_icmppkts[i];
2962 is->is_bytes[i] += fin->fin_plen;
2963 MUTEX_EXIT(&is->is_lock);
2964
2965 #ifdef IPFILTER_SYNC
2966 if (is->is_flags & IS_STATESYNC)
2967 ipfsync_update(SMC_STATE, fin, is->is_sync);
2968 #endif
2969
2970 ATOMIC_INCL(ifs->ifs_ips_stats.iss_hits);
2971
2972 fin->fin_fr = is->is_rule;
2973
2974 /*
2975 * If this packet is a fragment and the rule says to track fragments,
2976 * then create a new fragment cache entry.
2977 */
2978 pass = is->is_pass;
2979 if ((fin->fin_flx & FI_FRAG) && FR_ISPASS(pass))
2980 (void) fr_newfrag(fin, pass ^ FR_KEEPSTATE);
2981 }
2982
2983
2984 /* ------------------------------------------------------------------------ */
2985 /* Function: fr_checkstate */
2986 /* Returns: frentry_t* - NULL == search failed, */
2987 /* else pointer to rule for matching state */
2988 /* Parameters: ifp(I) - pointer to interface */
2989 /* passp(I) - pointer to filtering result flags */
2990 /* */
2991 /* Check if a packet is associated with an entry in the state table. */
2992 /* ------------------------------------------------------------------------ */
2993 frentry_t *fr_checkstate(fin, passp)
2994 fr_info_t *fin;
2995 u_32_t *passp;
2996 {
2997 ipstate_t *is;
2998 frentry_t *fr;
2999 tcphdr_t *tcp;
3000 ipftq_t *ifq;
3001 u_int pass;
3002 ipf_stack_t *ifs = fin->fin_ifs;
3003
3004 if (ifs->ifs_fr_state_lock || (ifs->ifs_ips_list == NULL) ||
3005 (fin->fin_flx & (FI_SHORT|FI_STATE|FI_FRAGBODY|FI_BAD)))
3006 return NULL;
3007
3008 is = NULL;
3009 if ((fin->fin_flx & FI_TCPUDP) ||
3010 (fin->fin_fi.fi_p == IPPROTO_ICMP)
3011 #ifdef USE_INET6
3012 || (fin->fin_fi.fi_p == IPPROTO_ICMPV6)
3013 #endif
3014 )
3015 tcp = fin->fin_dp;
3016 else
3017 tcp = NULL;
3018
3019 /*
3020 * Search the hash table for matching packet header info.
3021 */
3022 ifq = NULL;
3023 is = fr_stlookup(fin, tcp, &ifq);
3024 switch (fin->fin_p)
3025 {
3026 #ifdef USE_INET6
3027 case IPPROTO_ICMPV6 :
3028 if (is != NULL)
3029 break;
3030 if (fin->fin_v == 6) {
3031 is = fr_checkicmp6matchingstate(fin);
3032 if (is != NULL)
3033 goto matched;
3034 }
3035 break;
3036 #endif
3037 case IPPROTO_ICMP :
3038 if (is != NULL)
3039 break;
3040 /*
3041 * No matching icmp state entry. Perhaps this is a
3042 * response to another state entry.
3043 */
3044 is = fr_checkicmpmatchingstate(fin);
3045 if (is != NULL)
3046 goto matched;
3047 break;
3048 case IPPROTO_TCP :
3049 if (is == NULL)
3050 break;
3051
3052 if (is->is_pass & FR_NEWISN) {
3053 if (fin->fin_out == 0)
3054 fr_fixinisn(fin, is);
3055 else if (fin->fin_out == 1)
3056 fr_fixoutisn(fin, is);
3057 }
3058 break;
3059 default :
3060 if (fin->fin_rev)
3061 ifq = &ifs->ifs_ips_udpacktq;
3062 else
3063 ifq = &ifs->ifs_ips_udptq;
3064 break;
3065 }
3066 if (is == NULL) {
3067 ATOMIC_INCL(ifs->ifs_ips_stats.iss_miss);
3068 return NULL;
3069 }
3070
3071 matched:
3072 fr = is->is_rule;
3073 if (fr != NULL) {
3074 if ((fin->fin_out == 0) && (fr->fr_nattag.ipt_num[0] != 0)) {
3075 if (fin->fin_nattag == NULL) {
3076 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3077 return NULL;
3078 }
3079 if (fr_matchtag(&fr->fr_nattag, fin->fin_nattag) != 0) {
3080 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3081 return NULL;
3082 }
3083 }
3084 (void) strncpy(fin->fin_group, fr->fr_group, FR_GROUPLEN);
3085 fin->fin_icode = fr->fr_icode;
3086 }
3087
3088 fin->fin_rule = is->is_rulen;
3089 pass = is->is_pass;
3090 fr_updatestate(fin, is, ifq);
3091
3092 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3093 fin->fin_flx |= FI_STATE;
3094 if ((pass & FR_LOGFIRST) != 0)
3095 pass &= ~(FR_LOGFIRST|FR_LOG);
3096 *passp = pass;
3097 return fr;
3098 }
3099
3100
3101 /* ------------------------------------------------------------------------ */
3102 /* Function: fr_fixoutisn */
3103 /* Returns: Nil */
3104 /* Parameters: fin(I) - pointer to packet information */
3105 /* is(I) - pointer to master state structure */
3106 /* */
3107 /* Called only for outbound packets, adjusts the sequence number and the */
3108 /* TCP checksum to match that change. */
3109 /* ------------------------------------------------------------------------ */
3110 static void fr_fixoutisn(fin, is)
3111 fr_info_t *fin;
3112 ipstate_t *is;
3113 {
3114 tcphdr_t *tcp;
3115 int rev;
3116 u_32_t seq;
3117
3118 tcp = fin->fin_dp;
3119 rev = fin->fin_rev;
3120 if ((is->is_flags & IS_ISNSYN) != 0) {
3121 if (rev == 0) {
3122 seq = ntohl(tcp->th_seq);
3123 seq += is->is_isninc[0];
3124 tcp->th_seq = htonl(seq);
3125 fix_outcksum(&tcp->th_sum, is->is_sumd[0]);
3126 }
3127 }
3128 if ((is->is_flags & IS_ISNACK) != 0) {
3129 if (rev == 1) {
3130 seq = ntohl(tcp->th_seq);
3131 seq += is->is_isninc[1];
3132 tcp->th_seq = htonl(seq);
3133 fix_outcksum(&tcp->th_sum, is->is_sumd[1]);
3134 }
3135 }
3136 }
3137
3138
3139 /* ------------------------------------------------------------------------ */
3140 /* Function: fr_fixinisn */
3141 /* Returns: Nil */
3142 /* Parameters: fin(I) - pointer to packet information */
3143 /* is(I) - pointer to master state structure */
3144 /* */
3145 /* Called only for inbound packets, adjusts the acknowledge number and the */
3146 /* TCP checksum to match that change. */
3147 /* ------------------------------------------------------------------------ */
3148 static void fr_fixinisn(fin, is)
3149 fr_info_t *fin;
3150 ipstate_t *is;
3151 {
3152 tcphdr_t *tcp;
3153 int rev;
3154 u_32_t ack;
3155
3156 tcp = fin->fin_dp;
3157 rev = fin->fin_rev;
3158 if ((is->is_flags & IS_ISNSYN) != 0) {
3159 if (rev == 1) {
3160 ack = ntohl(tcp->th_ack);
3161 ack -= is->is_isninc[0];
3162 tcp->th_ack = htonl(ack);
3163 fix_incksum(&tcp->th_sum, is->is_sumd[0]);
3164 }
3165 }
3166 if ((is->is_flags & IS_ISNACK) != 0) {
3167 if (rev == 0) {
3168 ack = ntohl(tcp->th_ack);
3169 ack -= is->is_isninc[1];
3170 tcp->th_ack = htonl(ack);
3171 fix_incksum(&tcp->th_sum, is->is_sumd[1]);
3172 }
3173 }
3174 }
3175
3176
3177 /* ------------------------------------------------------------------------ */
3178 /* Function: fr_statesync */
3179 /* Returns: Nil */
3180 /* Parameters: action(I) - type of synchronisation to do */
3181 /* v(I) - IP version being sync'd (v4 or v6) */
3182 /* ifp(I) - interface identifier associated with action */
3183 /* name(I) - name associated with ifp parameter */
3184 /* */
3185 /* Walk through all state entries and if an interface pointer match is */
3186 /* found then look it up again, based on its name in case the pointer has */
3187 /* changed since last time. */
3188 /* */
3189 /* If ifp is passed in as being non-null then we are only doing updates for */
3190 /* existing, matching, uses of it. */
3191 /* ------------------------------------------------------------------------ */
3192 void fr_statesync(action, v, ifp, name, ifs)
3193 int action, v;
3194 void *ifp;
3195 char *name;
3196 ipf_stack_t *ifs;
3197 {
3198 ipstate_t *is;
3199 int i;
3200
3201 if (ifs->ifs_fr_running <= 0)
3202 return;
3203
3204 WRITE_ENTER(&ifs->ifs_ipf_state);
3205
3206 if (ifs->ifs_fr_running <= 0) {
3207 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3208 return;
3209 }
3210
3211 switch (action)
3212 {
3213 case IPFSYNC_RESYNC :
3214 for (is = ifs->ifs_ips_list; is; is = is->is_next) {
3215 if (v != 0 && is->is_v != v)
3216 continue;
3217 /*
3218 * Look up all the interface names in the state entry.
3219 */
3220 for (i = 0; i < 4; i++) {
3221 is->is_ifp[i] = fr_resolvenic(is->is_ifname[i],
3222 is->is_v, ifs);
3223 }
3224 }
3225 break;
3226 case IPFSYNC_NEWIFP :
3227 for (is = ifs->ifs_ips_list; is; is = is->is_next) {
3228 if (v != 0 && is->is_v != v)
3229 continue;
3230 /*
3231 * Look up all the interface names in the state entry.
3232 */
3233 for (i = 0; i < 4; i++) {
3234 if (!strncmp(is->is_ifname[i], name,
3235 sizeof(is->is_ifname[i])))
3236 is->is_ifp[i] = ifp;
3237 }
3238 }
3239 break;
3240 case IPFSYNC_OLDIFP :
3241 for (is = ifs->ifs_ips_list; is; is = is->is_next) {
3242 if (v != 0 && is->is_v != v)
3243 continue;
3244 /*
3245 * Look up all the interface names in the state entry.
3246 */
3247 for (i = 0; i < 4; i++) {
3248 if (is->is_ifp[i] == ifp)
3249 is->is_ifp[i] = (void *)-1;
3250 }
3251 }
3252 break;
3253 }
3254 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3255 }
3256
3257
3258 #if SOLARIS2 >= 10
3259 /* ------------------------------------------------------------------------ */
3260 /* Function: fr_stateifindexsync */
3261 /* Returns: void */
3262 /* Parameters: ifp - current network interface descriptor (ifindex) */
3263 /* newifp - new interface descriptor (new ifindex) */
3264 /* ifs - pointer to IPF stack */
3265 /* */
3266 /* Write Locks: assumes ipf_mutex is locked */
3267 /* */
3268 /* Updates all interface indeces matching to ifp with new interface index */
3269 /* value. */
3270 /* ------------------------------------------------------------------------ */
3271 void fr_stateifindexsync(ifp, newifp, ifs)
3272 void *ifp;
3273 void *newifp;
3274 ipf_stack_t *ifs;
3275 {
3276 ipstate_t *is;
3277 int i;
3278
3279 WRITE_ENTER(&ifs->ifs_ipf_state);
3280
3281 for (is = ifs->ifs_ips_list; is != NULL; is = is->is_next) {
3282
3283 for (i = 0; i < 4; i++) {
3284 if (is->is_ifp[i] == ifp)
3285 is->is_ifp[i] = newifp;
3286 }
3287 }
3288
3289 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3290 }
3291 #endif
3292
3293 /* ------------------------------------------------------------------------ */
3294 /* Function: fr_delstate */
3295 /* Returns: int - 0 = entry deleted, else ref count on entry */
3296 /* Parameters: is(I) - pointer to state structure to delete */
3297 /* why(I) - if not 0, log reason why it was deleted */
3298 /* ifs - ipf stack instance */
3299 /* Write Locks: ipf_state/ipf_global */
3300 /* */
3301 /* Deletes a state entry from the enumerated list as well as the hash table */
3302 /* and timeout queue lists. Make adjustments to hash table statistics and */
3303 /* global counters as required. */
3304 /* ------------------------------------------------------------------------ */
3305 int fr_delstate(is, why, ifs)
3306 ipstate_t *is;
3307 int why;
3308 ipf_stack_t *ifs;
3309 {
3310 int removed = 0;
3311
3312 ASSERT(rw_write_held(&ifs->ifs_ipf_global.ipf_lk) == 0 ||
3313 rw_write_held(&ifs->ifs_ipf_state.ipf_lk) == 0);
3314
3315 /*
3316 * Start by removing the entry from the hash table of state entries
3317 * so it will not be "used" again.
3318 *
3319 * It will remain in the "list" of state entries until all references
3320 * have been accounted for.
3321 */
3322 if (is->is_phnext != NULL) {
3323 removed = 1;
3324 *is->is_phnext = is->is_hnext;
3325 if (is->is_hnext != NULL)
3326 is->is_hnext->is_phnext = is->is_phnext;
3327 if (ifs->ifs_ips_table[is->is_hv] == NULL)
3328 ifs->ifs_ips_stats.iss_inuse--;
3329 ifs->ifs_ips_stats.iss_bucketlen[is->is_hv]--;
3330
3331 is->is_phnext = NULL;
3332 is->is_hnext = NULL;
3333 }
3334
3335 /*
3336 * Because ifs->ifs_ips_stats.iss_wild is a count of entries in the state
3337 * table that have wildcard flags set, only decerement it once
3338 * and do it here.
3339 */
3340 if (is->is_flags & (SI_WILDP|SI_WILDA)) {
3341 if (!(is->is_flags & SI_CLONED)) {
3342 ATOMIC_DECL(ifs->ifs_ips_stats.iss_wild);
3343 }
3344 is->is_flags &= ~(SI_WILDP|SI_WILDA);
3345 }
3346
3347 /*
3348 * Next, remove it from the timeout queue it is in.
3349 */
3350 fr_deletequeueentry(&is->is_sti);
3351
3352 is->is_me = NULL;
3353
3354 /*
3355 * If it is still in use by something else, do not go any further,
3356 * but note that at this point it is now an orphan.
3357 */
3358 MUTEX_ENTER(&is->is_lock);
3359 if (is->is_ref > 1) {
3360 is->is_ref--;
3361 MUTEX_EXIT(&is->is_lock);
3362 if (removed)
3363 ifs->ifs_ips_stats.iss_orphans++;
3364 return (is->is_ref);
3365 }
3366 MUTEX_EXIT(&is->is_lock);
3367
3368 is->is_ref = 0;
3369
3370 /*
3371 * If entry has already been removed from table,
3372 * it means we're simply cleaning up an orphan.
3373 */
3374 if (!removed)
3375 ifs->ifs_ips_stats.iss_orphans--;
3376
3377 if (is->is_tqehead[0] != NULL)
3378 (void) fr_deletetimeoutqueue(is->is_tqehead[0]);
3379
3380 if (is->is_tqehead[1] != NULL)
3381 (void) fr_deletetimeoutqueue(is->is_tqehead[1]);
3382
3383 #ifdef IPFILTER_SYNC
3384 if (is->is_sync)
3385 ipfsync_del(is->is_sync);
3386 #endif
3387 #ifdef IPFILTER_SCAN
3388 (void) ipsc_detachis(is);
3389 #endif
3390
3391 /*
3392 * Now remove it from master list of state table entries.
3393 */
3394 if (is->is_pnext != NULL) {
3395 *is->is_pnext = is->is_next;
3396 if (is->is_next != NULL) {
3397 is->is_next->is_pnext = is->is_pnext;
3398 is->is_next = NULL;
3399 }
3400 is->is_pnext = NULL;
3401 }
3402
3403 if (ifs->ifs_ipstate_logging != 0 && why != 0)
3404 ipstate_log(is, why, ifs);
3405 #if 0
3406 /*
3407 * For now, ipf_log_cfwlog() copes with all "why" values.
3408 * strictly speaking, though, they all map to one event, which for
3409 * now is not supported.
3410 */
3411 if (why != 0 && IFS_CFWLOG(ifs))
3412 ipf_log_cfwlog(is, why, ifs);
3413 #endif
3414 if (is->is_rule != NULL) {
3415 is->is_rule->fr_statecnt--;
3416 (void)fr_derefrule(&is->is_rule, ifs);
3417 }
3418
3419 MUTEX_DESTROY(&is->is_lock);
3420 KFREE(is);
3421 ifs->ifs_ips_num--;
3422
3423 return (0);
3424 }
3425
3426
3427 /* ------------------------------------------------------------------------ */
3428 /* Function: fr_timeoutstate */
3429 /* Returns: Nil */
3430 /* Parameters: ifs - ipf stack instance */
3431 /* */
3432 /* Slowly expire held state for thingslike UDP and ICMP. The algorithm */
3433 /* used here is to keep the queue sorted with the oldest things at the top */
3434 /* and the youngest at the bottom. So if the top one doesn't need to be */
3435 /* expired then neither will any under it. */
3436 /* ------------------------------------------------------------------------ */
3437 void fr_timeoutstate(ifs)
3438 ipf_stack_t *ifs;
3439 {
3440 ipftq_t *ifq, *ifqnext;
3441 ipftqent_t *tqe, *tqn;
3442 ipstate_t *is;
3443 SPL_INT(s);
3444
3445 SPL_NET(s);
3446 WRITE_ENTER(&ifs->ifs_ipf_state);
3447 for (ifq = ifs->ifs_ips_tqtqb; ifq != NULL; ifq = ifq->ifq_next)
3448 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) {
3449 if (tqe->tqe_die > ifs->ifs_fr_ticks)
3450 break;
3451 tqn = tqe->tqe_next;
3452 is = tqe->tqe_parent;
3453 (void) fr_delstate(is, ISL_EXPIRE, ifs);
3454 }
3455
3456 for (ifq = ifs->ifs_ips_utqe; ifq != NULL; ifq = ifq->ifq_next) {
3457 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) {
3458 if (tqe->tqe_die > ifs->ifs_fr_ticks)
3459 break;
3460 tqn = tqe->tqe_next;
3461 is = tqe->tqe_parent;
3462 (void) fr_delstate(is, ISL_EXPIRE, ifs);
3463 }
3464 }
3465
3466 for (ifq = ifs->ifs_ips_utqe; ifq != NULL; ifq = ifqnext) {
3467 ifqnext = ifq->ifq_next;
3468
3469 if (((ifq->ifq_flags & IFQF_DELETE) != 0) &&
3470 (ifq->ifq_ref == 0)) {
3471 fr_freetimeoutqueue(ifq, ifs);
3472 }
3473 }
3474
3475 if (ifs->ifs_fr_state_doflush) {
3476 (void) fr_state_flush(FLUSH_TABLE_EXTRA, 0, ifs);
3477 ifs->ifs_fr_state_doflush = 0;
3478 }
3479 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3480 SPL_X(s);
3481 }
3482
3483
3484 /* ---------------------------------------------------------------------- */
3485 /* Function: fr_state_flush */
3486 /* Returns: int - 0 == success, -1 == failure */
3487 /* Parameters: flush_option - how to flush the active State table */
3488 /* proto - IP version to flush (4, 6, or both) */
3489 /* ifs - ipf stack instance */
3490 /* Write Locks: ipf_state */
3491 /* */
3492 /* Flush state tables. Three possible flush options currently defined: */
3493 /* */
3494 /* FLUSH_TABLE_ALL : Flush all state table entries */
3495 /* */
3496 /* FLUSH_TABLE_CLOSING : Flush entries with TCP connections which */
3497 /* have started to close on both ends using */
3498 /* ipf_flushclosing(). */
3499 /* */
3500 /* FLUSH_TABLE_EXTRA : First, flush entries which are "almost" closed. */
3501 /* Then, if needed, flush entries with TCP */
3502 /* connections which have been idle for a long */
3503 /* time with ipf_extraflush(). */
3504 /* ---------------------------------------------------------------------- */
3505 static int fr_state_flush(flush_option, proto, ifs)
3506 int flush_option, proto;
3507 ipf_stack_t *ifs;
3508 {
3509 ipstate_t *is, *isn;
3510 int removed;
3511 SPL_INT(s);
3512
3513 removed = 0;
3514
3515 SPL_NET(s);
3516 switch (flush_option)
3517 {
3518 case FLUSH_TABLE_ALL:
3519 isn = ifs->ifs_ips_list;
3520 while ((is = isn) != NULL) {
3521 isn = is->is_next;
3522 if ((proto != 0) && (is->is_v != proto))
3523 continue;
3524 if (fr_delstate(is, ISL_FLUSH, ifs) == 0)
3525 removed++;
3526 }
3527 break;
3528
3529 case FLUSH_TABLE_CLOSING:
3530 removed = ipf_flushclosing(STATE_FLUSH,
3531 IPF_TCPS_CLOSE_WAIT,
3532 ifs->ifs_ips_tqtqb,
3533 ifs->ifs_ips_utqe,
3534 ifs);
3535 break;
3536
3537 case FLUSH_TABLE_EXTRA:
3538 removed = ipf_flushclosing(STATE_FLUSH,
3539 IPF_TCPS_FIN_WAIT_2,
3540 ifs->ifs_ips_tqtqb,
3541 ifs->ifs_ips_utqe,
3542 ifs);
3543
3544 /*
3545 * Be sure we haven't done this in the last 10 seconds.
3546 */
3547 if (ifs->ifs_fr_ticks - ifs->ifs_ips_last_force_flush <
3548 IPF_TTLVAL(10))
3549 break;
3550 ifs->ifs_ips_last_force_flush = ifs->ifs_fr_ticks;
3551 removed += ipf_extraflush(STATE_FLUSH,
3552 &ifs->ifs_ips_tqtqb[IPF_TCPS_ESTABLISHED],
3553 ifs->ifs_ips_utqe,
3554 ifs);
3555 break;
3556
3557 default: /* Flush Nothing */
3558 break;
3559 }
3560
3561 SPL_X(s);
3562 return (removed);
3563 }
3564
3565
3566 /* ------------------------------------------------------------------------ */
3567 /* Function: fr_tcp_age */
3568 /* Returns: int - 1 == state transition made, 0 == no change (rejected) */
3569 /* Parameters: tq(I) - pointer to timeout queue information */
3570 /* fin(I) - pointer to packet information */
3571 /* tqtab(I) - TCP timeout queue table this is in */
3572 /* flags(I) - flags from state/NAT entry */
3573 /* */
3574 /* Rewritten by Arjan de Vet <Arjan.deVet@adv.iae.nl>, 2000-07-29: */
3575 /* */
3576 /* - (try to) base state transitions on real evidence only, */
3577 /* i.e. packets that are sent and have been received by ipfilter; */
3578 /* diagram 18.12 of TCP/IP volume 1 by W. Richard Stevens was used. */
3579 /* */
3580 /* - deal with half-closed connections correctly; */
3581 /* */
3582 /* - store the state of the source in state[0] such that ipfstat */
3583 /* displays the state as source/dest instead of dest/source; the calls */
3584 /* to fr_tcp_age have been changed accordingly. */
3585 /* */
3586 /* Internal Parameters: */
3587 /* */
3588 /* state[0] = state of source (host that initiated connection) */
3589 /* state[1] = state of dest (host that accepted the connection) */
3590 /* */
3591 /* dir == 0 : a packet from source to dest */
3592 /* dir == 1 : a packet from dest to source */
3593 /* */
3594 /* Locking: it is assumed that the parent of the tqe structure is locked. */
3595 /* ------------------------------------------------------------------------ */
3596 int fr_tcp_age(tqe, fin, tqtab, flags)
3597 ipftqent_t *tqe;
3598 fr_info_t *fin;
3599 ipftq_t *tqtab;
3600 int flags;
3601 {
3602 int dlen, ostate, nstate, rval, dir;
3603 u_char tcpflags;
3604 tcphdr_t *tcp;
3605 ipf_stack_t *ifs = fin->fin_ifs;
3606
3607 tcp = fin->fin_dp;
3608
3609 rval = 0;
3610 dir = fin->fin_rev;
3611 tcpflags = tcp->th_flags;
3612 dlen = fin->fin_dlen - (TCP_OFF(tcp) << 2);
3613
3614 ostate = tqe->tqe_state[1 - dir];
3615 nstate = tqe->tqe_state[dir];
3616
3617 DTRACE_PROBE4(
3618 indata,
3619 fr_info_t *, fin,
3620 int, ostate,
3621 int, nstate,
3622 u_char, tcpflags
3623 );
3624
3625 if (tcpflags & TH_RST) {
3626 if (!(tcpflags & TH_PUSH) && !dlen)
3627 nstate = IPF_TCPS_CLOSED;
3628 else
3629 nstate = IPF_TCPS_CLOSE_WAIT;
3630
3631 /*
3632 * Once RST is received, we must advance peer's state to
3633 * CLOSE_WAIT.
3634 */
3635 if (ostate <= IPF_TCPS_ESTABLISHED) {
3636 tqe->tqe_state[1 - dir] = IPF_TCPS_CLOSE_WAIT;
3637 }
3638 rval = 1;
3639 } else {
3640
3641 switch (nstate)
3642 {
3643 case IPF_TCPS_LISTEN: /* 0 */
3644 if ((tcpflags & TH_OPENING) == TH_OPENING) {
3645 /*
3646 * 'dir' received an S and sends SA in
3647 * response, CLOSED -> SYN_RECEIVED
3648 */
3649 nstate = IPF_TCPS_SYN_RECEIVED;
3650 rval = 1;
3651 } else if ((tcpflags & TH_OPENING) == TH_SYN) {
3652 /* 'dir' sent S, CLOSED -> SYN_SENT */
3653 nstate = IPF_TCPS_SYN_SENT;
3654 rval = 1;
3655 }
3656 /*
3657 * the next piece of code makes it possible to get
3658 * already established connections into the state table
3659 * after a restart or reload of the filter rules; this
3660 * does not work when a strict 'flags S keep state' is
3661 * used for tcp connections of course
3662 */
3663 if (((flags & IS_TCPFSM) == 0) &&
3664 ((tcpflags & TH_ACKMASK) == TH_ACK)) {
3665 /*
3666 * we saw an A, guess 'dir' is in ESTABLISHED
3667 * mode
3668 */
3669 switch (ostate)
3670 {
3671 case IPF_TCPS_LISTEN :
3672 case IPF_TCPS_SYN_RECEIVED :
3673 nstate = IPF_TCPS_HALF_ESTAB;
3674 rval = 1;
3675 break;
3676 case IPF_TCPS_HALF_ESTAB :
3677 case IPF_TCPS_ESTABLISHED :
3678 nstate = IPF_TCPS_ESTABLISHED;
3679 rval = 1;
3680 break;
3681 default :
3682 break;
3683 }
3684 }
3685 /*
3686 * TODO: besides regular ACK packets we can have other
3687 * packets as well; it is yet to be determined how we
3688 * should initialize the states in those cases
3689 */
3690 break;
3691
3692 case IPF_TCPS_SYN_SENT: /* 1 */
3693 if ((tcpflags & ~(TH_ECN|TH_CWR)) == TH_SYN) {
3694 /*
3695 * A retransmitted SYN packet. We do not reset
3696 * the timeout here to fr_tcptimeout because a
3697 * connection connect timeout does not renew
3698 * after every packet that is sent. We need to
3699 * set rval so as to indicate the packet has
3700 * passed the check for its flags being valid
3701 * in the TCP FSM. Setting rval to 2 has the
3702 * result of not resetting the timeout.
3703 */
3704 rval = 2;
3705 } else if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) ==
3706 TH_ACK) {
3707 /*
3708 * we see an A from 'dir' which is in SYN_SENT
3709 * state: 'dir' sent an A in response to an SA
3710 * which it received, SYN_SENT -> ESTABLISHED
3711 */
3712 nstate = IPF_TCPS_ESTABLISHED;
3713 rval = 1;
3714 } else if (tcpflags & TH_FIN) {
3715 /*
3716 * we see an F from 'dir' which is in SYN_SENT
3717 * state and wants to close its side of the
3718 * connection; SYN_SENT -> FIN_WAIT_1
3719 */
3720 nstate = IPF_TCPS_FIN_WAIT_1;
3721 rval = 1;
3722 } else if ((tcpflags & TH_OPENING) == TH_OPENING) {
3723 /*
3724 * we see an SA from 'dir' which is already in
3725 * SYN_SENT state, this means we have a
3726 * simultaneous open; SYN_SENT -> SYN_RECEIVED
3727 */
3728 nstate = IPF_TCPS_SYN_RECEIVED;
3729 rval = 1;
3730 }
3731 break;
3732
3733 case IPF_TCPS_SYN_RECEIVED: /* 2 */
3734 if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) == TH_ACK) {
3735 /*
3736 * we see an A from 'dir' which was in
3737 * SYN_RECEIVED state so it must now be in
3738 * established state, SYN_RECEIVED ->
3739 * ESTABLISHED
3740 */
3741 nstate = IPF_TCPS_ESTABLISHED;
3742 rval = 1;
3743 } else if ((tcpflags & ~(TH_ECN|TH_CWR)) ==
3744 TH_OPENING) {
3745 /*
3746 * We see an SA from 'dir' which is already in
3747 * SYN_RECEIVED state.
3748 */
3749 rval = 2;
3750 } else if (tcpflags & TH_FIN) {
3751 /*
3752 * we see an F from 'dir' which is in
3753 * SYN_RECEIVED state and wants to close its
3754 * side of the connection; SYN_RECEIVED ->
3755 * FIN_WAIT_1
3756 */
3757 nstate = IPF_TCPS_FIN_WAIT_1;
3758 rval = 1;
3759 }
3760 break;
3761
3762 case IPF_TCPS_HALF_ESTAB: /* 3 */
3763 if (tcpflags & TH_FIN) {
3764 nstate = IPF_TCPS_FIN_WAIT_1;
3765 rval = 1;
3766 } else if ((tcpflags & TH_ACKMASK) == TH_ACK) {
3767 /*
3768 * If we've picked up a connection in mid
3769 * flight, we could be looking at a follow on
3770 * packet from the same direction as the one
3771 * that created this state. Recognise it but
3772 * do not advance the entire connection's
3773 * state.
3774 */
3775 switch (ostate)
3776 {
3777 case IPF_TCPS_LISTEN :
3778 case IPF_TCPS_SYN_SENT :
3779 case IPF_TCPS_SYN_RECEIVED :
3780 rval = 1;
3781 break;
3782 case IPF_TCPS_HALF_ESTAB :
3783 case IPF_TCPS_ESTABLISHED :
3784 nstate = IPF_TCPS_ESTABLISHED;
3785 rval = 1;
3786 break;
3787 default :
3788 break;
3789 }
3790 }
3791 break;
3792
3793 case IPF_TCPS_ESTABLISHED: /* 4 */
3794 rval = 1;
3795 if (tcpflags & TH_FIN) {
3796 /*
3797 * 'dir' closed its side of the connection;
3798 * this gives us a half-closed connection;
3799 * ESTABLISHED -> FIN_WAIT_1
3800 */
3801 if (ostate == IPF_TCPS_FIN_WAIT_1) {
3802 nstate = IPF_TCPS_CLOSING;
3803 } else {
3804 nstate = IPF_TCPS_FIN_WAIT_1;
3805 }
3806 } else if (tcpflags & TH_ACK) {
3807 /*
3808 * an ACK, should we exclude other flags here?
3809 */
3810 if (ostate == IPF_TCPS_FIN_WAIT_1) {
3811 /*
3812 * We know the other side did an active
3813 * close, so we are ACKing the recvd
3814 * FIN packet (does the window matching
3815 * code guarantee this?) and go into
3816 * CLOSE_WAIT state; this gives us a
3817 * half-closed connection
3818 */
3819 nstate = IPF_TCPS_CLOSE_WAIT;
3820 } else if (ostate < IPF_TCPS_CLOSE_WAIT) {
3821 /*
3822 * still a fully established
3823 * connection reset timeout
3824 */
3825 nstate = IPF_TCPS_ESTABLISHED;
3826 }
3827 }
3828 break;
3829
3830 case IPF_TCPS_CLOSE_WAIT: /* 5 */
3831 rval = 1;
3832 if (tcpflags & TH_FIN) {
3833 /*
3834 * application closed and 'dir' sent a FIN,
3835 * we're now going into LAST_ACK state
3836 */
3837 nstate = IPF_TCPS_LAST_ACK;
3838 } else {
3839 /*
3840 * we remain in CLOSE_WAIT because the other
3841 * side has closed already and we did not
3842 * close our side yet; reset timeout
3843 */
3844 nstate = IPF_TCPS_CLOSE_WAIT;
3845 }
3846 break;
3847
3848 case IPF_TCPS_FIN_WAIT_1: /* 6 */
3849 rval = 1;
3850 if ((tcpflags & TH_ACK) &&
3851 ostate > IPF_TCPS_CLOSE_WAIT) {
3852 /*
3853 * if the other side is not active anymore
3854 * it has sent us a FIN packet that we are
3855 * ack'ing now with an ACK; this means both
3856 * sides have now closed the connection and
3857 * we go into LAST_ACK
3858 */
3859 /*
3860 * XXX: how do we know we really are ACKing
3861 * the FIN packet here? does the window code
3862 * guarantee that?
3863 */
3864 nstate = IPF_TCPS_LAST_ACK;
3865 } else {
3866 /*
3867 * we closed our side of the connection
3868 * already but the other side is still active
3869 * (ESTABLISHED/CLOSE_WAIT); continue with
3870 * this half-closed connection
3871 */
3872 nstate = IPF_TCPS_FIN_WAIT_1;
3873 }
3874 break;
3875
3876 case IPF_TCPS_CLOSING: /* 7 */
3877 if ((tcpflags & (TH_FIN|TH_ACK)) == TH_ACK) {
3878 nstate = IPF_TCPS_TIME_WAIT;
3879 }
3880 rval = 1;
3881 break;
3882
3883 case IPF_TCPS_LAST_ACK: /* 8 */
3884 /*
3885 * We want to reset timer here to keep state in table.
3886 * If we would allow the state to time out here, while
3887 * there would still be packets being retransmitted, we
3888 * would cut off line between the two peers preventing
3889 * them to close connection properly.
3890 */
3891 rval = 1;
3892 break;
3893
3894 case IPF_TCPS_FIN_WAIT_2: /* 9 */
3895 /* NOT USED */
3896 break;
3897
3898 case IPF_TCPS_TIME_WAIT: /* 10 */
3899 /* we're in 2MSL timeout now */
3900 if (ostate == IPF_TCPS_LAST_ACK) {
3901 nstate = IPF_TCPS_CLOSED;
3902 rval = 1;
3903 } else {
3904 rval = 2;
3905 }
3906 break;
3907
3908 case IPF_TCPS_CLOSED: /* 11 */
3909 rval = 2;
3910 break;
3911
3912 default :
3913 #if defined(_KERNEL)
3914 ASSERT(nstate >= IPF_TCPS_LISTEN &&
3915 nstate <= IPF_TCPS_CLOSED);
3916 #else
3917 abort();
3918 #endif
3919 break;
3920 }
3921 }
3922
3923 /*
3924 * If rval == 2 then do not update the queue position, but treat the
3925 * packet as being ok.
3926 */
3927 if (rval == 2) {
3928 DTRACE_PROBE1(state_keeping_timer, int, nstate);
3929 rval = 1;
3930 }
3931 else if (rval == 1) {
3932 tqe->tqe_state[dir] = nstate;
3933 /*
3934 * The nstate can either advance to a new state, or remain
3935 * unchanged, resetting the timer by moving to the bottom of
3936 * the queue.
3937 */
3938 DTRACE_PROBE1(state_done, int, nstate);
3939
3940 if ((tqe->tqe_flags & TQE_RULEBASED) == 0)
3941 fr_movequeue(tqe, tqe->tqe_ifq, tqtab + nstate, ifs);
3942 }
3943
3944 return rval;
3945 }
3946
3947 /* ------------------------------------------------------------------------ */
3948 /* Function: ipstate_log */
3949 /* Returns: Nil */
3950 /* Parameters: is(I) - pointer to state structure */
3951 /* type(I) - type of log entry to create */
3952 /* */
3953 /* Creates a state table log entry using the state structure and type info. */
3954 /* passed in. Log packet/byte counts, source/destination address and other */
3955 /* protocol specific information. */
3956 /* ------------------------------------------------------------------------ */
3957 void ipstate_log(is, type, ifs)
3958 struct ipstate *is;
3959 u_int type;
3960 ipf_stack_t *ifs;
3961 {
3962 #ifdef IPFILTER_LOG
3963 struct ipslog ipsl;
3964 size_t sizes[1];
3965 void *items[1];
3966 int types[1];
3967
3968 /*
3969 * Copy information out of the ipstate_t structure and into the
3970 * structure used for logging.
3971 */
3972 ipsl.isl_type = type;
3973 ipsl.isl_pkts[0] = is->is_pkts[0] + is->is_icmppkts[0];
3974 ipsl.isl_bytes[0] = is->is_bytes[0];
3975 ipsl.isl_pkts[1] = is->is_pkts[1] + is->is_icmppkts[1];
3976 ipsl.isl_bytes[1] = is->is_bytes[1];
3977 ipsl.isl_pkts[2] = is->is_pkts[2] + is->is_icmppkts[2];
3978 ipsl.isl_bytes[2] = is->is_bytes[2];
3979 ipsl.isl_pkts[3] = is->is_pkts[3] + is->is_icmppkts[3];
3980 ipsl.isl_bytes[3] = is->is_bytes[3];
3981 ipsl.isl_src = is->is_src;
3982 ipsl.isl_dst = is->is_dst;
3983 ipsl.isl_p = is->is_p;
3984 ipsl.isl_v = is->is_v;
3985 ipsl.isl_flags = is->is_flags;
3986 ipsl.isl_tag = is->is_tag;
3987 ipsl.isl_rulen = is->is_rulen;
3988 (void) strncpy(ipsl.isl_group, is->is_group, FR_GROUPLEN);
3989
3990 if (ipsl.isl_p == IPPROTO_TCP || ipsl.isl_p == IPPROTO_UDP) {
3991 ipsl.isl_sport = is->is_sport;
3992 ipsl.isl_dport = is->is_dport;
3993 if (ipsl.isl_p == IPPROTO_TCP) {
3994 ipsl.isl_state[0] = is->is_state[0];
3995 ipsl.isl_state[1] = is->is_state[1];
3996 }
3997 } else if (ipsl.isl_p == IPPROTO_ICMP) {
3998 ipsl.isl_itype = is->is_icmp.ici_type;
3999 } else if (ipsl.isl_p == IPPROTO_ICMPV6) {
4000 ipsl.isl_itype = is->is_icmp.ici_type;
4001 } else {
4002 ipsl.isl_ps.isl_filler[0] = 0;
4003 ipsl.isl_ps.isl_filler[1] = 0;
4004 }
4005
4006 items[0] = &ipsl;
4007 sizes[0] = sizeof(ipsl);
4008 types[0] = 0;
4009
4010 if (ipllog(IPL_LOGSTATE, NULL, items, sizes, types, 1, ifs)) {
4011 ATOMIC_INCL(ifs->ifs_ips_stats.iss_logged);
4012 } else {
4013 ATOMIC_INCL(ifs->ifs_ips_stats.iss_logfail);
4014 }
4015 #endif
4016 }
4017
4018
4019 #ifdef USE_INET6
4020 /* ------------------------------------------------------------------------ */
4021 /* Function: fr_checkicmp6matchingstate */
4022 /* Returns: ipstate_t* - NULL == no match found, */
4023 /* else pointer to matching state entry */
4024 /* Parameters: fin(I) - pointer to packet information */
4025 /* Locks: NULL == no locks, else Read Lock on ipf_state */
4026 /* */
4027 /* If we've got an ICMPv6 error message, using the information stored in */
4028 /* the ICMPv6 packet, look for a matching state table entry. */
4029 /* ------------------------------------------------------------------------ */
4030 static ipstate_t *fr_checkicmp6matchingstate(fin)
4031 fr_info_t *fin;
4032 {
4033 struct icmp6_hdr *ic6, *oic;
4034 int backward, i;
4035 ipstate_t *is, **isp;
4036 u_short sport, dport;
4037 i6addr_t dst, src;
4038 u_short savelen;
4039 icmpinfo_t *ic;
4040 fr_info_t ofin;
4041 tcphdr_t *tcp;
4042 ip6_t *oip6;
4043 u_char pr;
4044 u_int hv;
4045 ipf_stack_t *ifs = fin->fin_ifs;
4046
4047 /*
4048 * Does it at least have the return (basic) IP header ?
4049 * Is it an actual recognised ICMP error type?
4050 * Only a basic IP header (no options) should be with
4051 * an ICMP error header.
4052 */
4053 if ((fin->fin_v != 6) || (fin->fin_plen < ICMP6ERR_MINPKTLEN) ||
4054 !(fin->fin_flx & FI_ICMPERR))
4055 return NULL;
4056
4057 ic6 = fin->fin_dp;
4058
4059 oip6 = (ip6_t *)((char *)ic6 + ICMPERR_ICMPHLEN);
4060 if (fin->fin_plen < sizeof(*oip6))
4061 return NULL;
4062
4063 bcopy((char *)fin, (char *)&ofin, sizeof(*fin));
4064 ofin.fin_v = 6;
4065 ofin.fin_ifp = fin->fin_ifp;
4066 ofin.fin_out = !fin->fin_out;
4067 ofin.fin_m = NULL; /* if dereferenced, panic XXX */
4068 ofin.fin_mp = NULL; /* if dereferenced, panic XXX */
4069
4070 /*
4071 * We make a fin entry to be able to feed it to
4072 * matchsrcdst. Note that not all fields are necessary
4073 * but this is the cleanest way. Note further we fill
4074 * in fin_mp such that if someone uses it we'll get
4075 * a kernel panic. fr_matchsrcdst does not use this.
4076 *
4077 * watch out here, as ip is in host order and oip6 in network
4078 * order. Any change we make must be undone afterwards.
4079 */
4080 savelen = oip6->ip6_plen;
4081 oip6->ip6_plen = fin->fin_dlen - ICMPERR_ICMPHLEN;
4082 ofin.fin_flx = FI_NOCKSUM;
4083 ofin.fin_ip = (ip_t *)oip6;
4084 ofin.fin_plen = oip6->ip6_plen;
4085 (void) fr_makefrip(sizeof(*oip6), (ip_t *)oip6, &ofin);
4086 ofin.fin_flx &= ~(FI_BAD|FI_SHORT);
4087 oip6->ip6_plen = savelen;
4088
4089 if (oip6->ip6_nxt == IPPROTO_ICMPV6) {
4090 oic = (struct icmp6_hdr *)(oip6 + 1);
4091 /*
4092 * an ICMP error can only be generated as a result of an
4093 * ICMP query, not as the response on an ICMP error
4094 *
4095 * XXX theoretically ICMP_ECHOREP and the other reply's are
4096 * ICMP query's as well, but adding them here seems strange XXX
4097 */
4098 if (!(oic->icmp6_type & ICMP6_INFOMSG_MASK))
4099 return NULL;
4100
4101 /*
4102 * perform a lookup of the ICMP packet in the state table
4103 */
4104 hv = (pr = oip6->ip6_nxt);
4105 src.in6 = oip6->ip6_src;
4106 hv += src.in4.s_addr;
4107 dst.in6 = oip6->ip6_dst;
4108 hv += dst.in4.s_addr;
4109 hv += oic->icmp6_id;
4110 hv += oic->icmp6_seq;
4111 hv = DOUBLE_HASH(hv, ifs);
4112
4113 READ_ENTER(&ifs->ifs_ipf_state);
4114 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) {
4115 ic = &is->is_icmp;
4116 isp = &is->is_hnext;
4117 if ((is->is_p == pr) &&
4118 !(is->is_pass & FR_NOICMPERR) &&
4119 (oic->icmp6_id == ic->ici_id) &&
4120 (oic->icmp6_seq == ic->ici_seq) &&
4121 (is = fr_matchsrcdst(&ofin, is, &src,
4122 &dst, NULL, FI_ICMPCMP))) {
4123 /*
4124 * in the state table ICMP query's are stored
4125 * with the type of the corresponding ICMP
4126 * response. Correct here
4127 */
4128 if (((ic->ici_type == ICMP6_ECHO_REPLY) &&
4129 (oic->icmp6_type == ICMP6_ECHO_REQUEST)) ||
4130 (ic->ici_type - 1 == oic->icmp6_type )) {
4131 ifs->ifs_ips_stats.iss_hits++;
4132 backward = IP6_NEQ(&is->is_dst, &src);
4133 fin->fin_rev = !backward;
4134 i = (backward << 1) + fin->fin_out;
4135 is->is_icmppkts[i]++;
4136 return is;
4137 }
4138 }
4139 }
4140 RWLOCK_EXIT(&ifs->ifs_ipf_state);
4141 return NULL;
4142 }
4143
4144 hv = (pr = oip6->ip6_nxt);
4145 src.in6 = oip6->ip6_src;
4146 hv += src.i6[0];
4147 hv += src.i6[1];
4148 hv += src.i6[2];
4149 hv += src.i6[3];
4150 dst.in6 = oip6->ip6_dst;
4151 hv += dst.i6[0];
4152 hv += dst.i6[1];
4153 hv += dst.i6[2];
4154 hv += dst.i6[3];
4155
4156 if ((oip6->ip6_nxt == IPPROTO_TCP) || (oip6->ip6_nxt == IPPROTO_UDP)) {
4157 tcp = (tcphdr_t *)(oip6 + 1);
4158 dport = tcp->th_dport;
4159 sport = tcp->th_sport;
4160 hv += dport;
4161 hv += sport;
4162 } else
4163 tcp = NULL;
4164 hv = DOUBLE_HASH(hv, ifs);
4165
4166 READ_ENTER(&ifs->ifs_ipf_state);
4167 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) {
4168 isp = &is->is_hnext;
4169 /*
4170 * Only allow this icmp though if the
4171 * encapsulated packet was allowed through the
4172 * other way around. Note that the minimal amount
4173 * of info present does not allow for checking against
4174 * tcp internals such as seq and ack numbers.
4175 */
4176 if ((is->is_p != pr) || (is->is_v != 6) ||
4177 (is->is_pass & FR_NOICMPERR))
4178 continue;
4179 is = fr_matchsrcdst(&ofin, is, &src, &dst, tcp, FI_ICMPCMP);
4180 if (is != NULL) {
4181 ifs->ifs_ips_stats.iss_hits++;
4182 backward = IP6_NEQ(&is->is_dst, &src);
4183 fin->fin_rev = !backward;
4184 i = (backward << 1) + fin->fin_out;
4185 is->is_icmppkts[i]++;
4186 /*
4187 * we deliberately do not touch the timeouts
4188 * for the accompanying state table entry.
4189 * It remains to be seen if that is correct. XXX
4190 */
4191 return is;
4192 }
4193 }
4194 RWLOCK_EXIT(&ifs->ifs_ipf_state);
4195 return NULL;
4196 }
4197 #endif
4198
4199
4200 /* ------------------------------------------------------------------------ */
4201 /* Function: fr_sttab_init */
4202 /* Returns: Nil */
4203 /* Parameters: tqp(I) - pointer to an array of timeout queues for TCP */
4204 /* */
4205 /* Initialise the array of timeout queues for TCP. */
4206 /* ------------------------------------------------------------------------ */
4207 void fr_sttab_init(tqp, ifs)
4208 ipftq_t *tqp;
4209 ipf_stack_t *ifs;
4210 {
4211 int i;
4212
4213 for (i = IPF_TCP_NSTATES - 1; i >= 0; i--) {
4214 tqp[i].ifq_ttl = 0;
4215 tqp[i].ifq_ref = 1;
4216 tqp[i].ifq_head = NULL;
4217 tqp[i].ifq_tail = &tqp[i].ifq_head;
4218 tqp[i].ifq_next = tqp + i + 1;
4219 MUTEX_INIT(&tqp[i].ifq_lock, "ipftq tcp tab");
4220 }
4221 tqp[IPF_TCP_NSTATES - 1].ifq_next = NULL;
4222 tqp[IPF_TCPS_CLOSED].ifq_ttl = ifs->ifs_fr_tcpclosed;
4223 tqp[IPF_TCPS_LISTEN].ifq_ttl = ifs->ifs_fr_tcptimeout;
4224 tqp[IPF_TCPS_SYN_SENT].ifq_ttl = ifs->ifs_fr_tcptimeout;
4225 tqp[IPF_TCPS_SYN_RECEIVED].ifq_ttl = ifs->ifs_fr_tcptimeout;
4226 tqp[IPF_TCPS_ESTABLISHED].ifq_ttl = ifs->ifs_fr_tcpidletimeout;
4227 tqp[IPF_TCPS_CLOSE_WAIT].ifq_ttl = ifs->ifs_fr_tcphalfclosed;
4228 tqp[IPF_TCPS_FIN_WAIT_1].ifq_ttl = ifs->ifs_fr_tcphalfclosed;
4229 tqp[IPF_TCPS_CLOSING].ifq_ttl = ifs->ifs_fr_tcptimeout;
4230 tqp[IPF_TCPS_LAST_ACK].ifq_ttl = ifs->ifs_fr_tcplastack;
4231 tqp[IPF_TCPS_FIN_WAIT_2].ifq_ttl = ifs->ifs_fr_tcpclosewait;
4232 tqp[IPF_TCPS_TIME_WAIT].ifq_ttl = ifs->ifs_fr_tcptimeout;
4233 tqp[IPF_TCPS_HALF_ESTAB].ifq_ttl = ifs->ifs_fr_tcptimeout;
4234 }
4235
4236
4237 /* ------------------------------------------------------------------------ */
4238 /* Function: fr_sttab_destroy */
4239 /* Returns: Nil */
4240 /* Parameters: tqp(I) - pointer to an array of timeout queues for TCP */
4241 /* */
4242 /* Do whatever is necessary to "destroy" each of the entries in the array */
4243 /* of timeout queues for TCP. */
4244 /* ------------------------------------------------------------------------ */
4245 void fr_sttab_destroy(tqp)
4246 ipftq_t *tqp;
4247 {
4248 int i;
4249
4250 for (i = IPF_TCP_NSTATES - 1; i >= 0; i--)
4251 MUTEX_DESTROY(&tqp[i].ifq_lock);
4252 }
4253
4254
4255 /* ------------------------------------------------------------------------ */
4256 /* Function: fr_statederef */
4257 /* Returns: Nil */
4258 /* Parameters: isp(I) - pointer to pointer to state table entry */
4259 /* ifs - ipf stack instance */
4260 /* */
4261 /* Decrement the reference counter for this state table entry and free it */
4262 /* if there are no more things using it. */
4263 /* */
4264 /* Internal parameters: */
4265 /* state[0] = state of source (host that initiated connection) */
4266 /* state[1] = state of dest (host that accepted the connection) */
4267 /* ------------------------------------------------------------------------ */
4268 void fr_statederef(isp, ifs)
4269 ipstate_t **isp;
4270 ipf_stack_t *ifs;
4271 {
4272 ipstate_t *is;
4273
4274 is = *isp;
4275 *isp = NULL;
4276
4277 MUTEX_ENTER(&is->is_lock);
4278 if (is->is_ref > 1) {
4279 is->is_ref--;
4280 MUTEX_EXIT(&is->is_lock);
4281 #ifndef _KERNEL
4282 if ((is->is_sti.tqe_state[0] > IPF_TCPS_ESTABLISHED) ||
4283 (is->is_sti.tqe_state[1] > IPF_TCPS_ESTABLISHED)) {
4284 (void) fr_delstate(is, ISL_ORPHAN, ifs);
4285 }
4286 #endif
4287 return;
4288 }
4289 MUTEX_EXIT(&is->is_lock);
4290
4291 WRITE_ENTER(&ifs->ifs_ipf_state);
4292 (void) fr_delstate(is, ISL_EXPIRE, ifs);
4293 RWLOCK_EXIT(&ifs->ifs_ipf_state);
4294 }
4295
4296
4297 /* ------------------------------------------------------------------------ */
4298 /* Function: fr_setstatequeue */
4299 /* Returns: Nil */
4300 /* Parameters: is(I) - pointer to state structure */
4301 /* rev(I) - forward(0) or reverse(1) direction */
4302 /* Locks: ipf_state (read or write) */
4303 /* */
4304 /* Put the state entry on its default queue entry, using rev as a helped in */
4305 /* determining which queue it should be placed on. */
4306 /* ------------------------------------------------------------------------ */
4307 void fr_setstatequeue(is, rev, ifs)
4308 ipstate_t *is;
4309 int rev;
4310 ipf_stack_t *ifs;
4311 {
4312 ipftq_t *oifq, *nifq;
4313
4314
4315 if ((is->is_sti.tqe_flags & TQE_RULEBASED) != 0)
4316 nifq = is->is_tqehead[rev];
4317 else
4318 nifq = NULL;
4319
4320 if (nifq == NULL) {
4321 switch (is->is_p)
4322 {
4323 #ifdef USE_INET6
4324 case IPPROTO_ICMPV6 :
4325 if (rev == 1)
4326 nifq = &ifs->ifs_ips_icmpacktq;
4327 else
4328 nifq = &ifs->ifs_ips_icmptq;
4329 break;
4330 #endif
4331 case IPPROTO_ICMP :
4332 if (rev == 1)
4333 nifq = &ifs->ifs_ips_icmpacktq;
4334 else
4335 nifq = &ifs->ifs_ips_icmptq;
4336 break;
4337 case IPPROTO_TCP :
4338 nifq = ifs->ifs_ips_tqtqb + is->is_state[rev];
4339 break;
4340
4341 case IPPROTO_UDP :
4342 if (rev == 1)
4343 nifq = &ifs->ifs_ips_udpacktq;
4344 else
4345 nifq = &ifs->ifs_ips_udptq;
4346 break;
4347
4348 default :
4349 nifq = &ifs->ifs_ips_iptq;
4350 break;
4351 }
4352 }
4353
4354 oifq = is->is_sti.tqe_ifq;
4355 /*
4356 * If it's currently on a timeout queue, move it from one queue to
4357 * another, else put it on the end of the newly determined queue.
4358 */
4359 if (oifq != NULL)
4360 fr_movequeue(&is->is_sti, oifq, nifq, ifs);
4361 else
4362 fr_queueappend(&is->is_sti, nifq, is, ifs);
4363 return;
4364 }
4365
4366
4367 /* ------------------------------------------------------------------------ */
4368 /* Function: fr_stateiter */
4369 /* Returns: int - 0 == success, else error */
4370 /* Parameters: token(I) - pointer to ipftoken structure */
4371 /* itp(I) - pointer to ipfgeniter structure */
4372 /* */
4373 /* This function handles the SIOCGENITER ioctl for the state tables and */
4374 /* walks through the list of entries in the state table list (ips_list.) */
4375 /* ------------------------------------------------------------------------ */
4376 static int fr_stateiter(token, itp, ifs)
4377 ipftoken_t *token;
4378 ipfgeniter_t *itp;
4379 ipf_stack_t *ifs;
4380 {
4381 ipstate_t *is, *next, zero;
4382 int error, count;
4383 char *dst;
4384
4385 if (itp->igi_data == NULL)
4386 return EFAULT;
4387
4388 if (itp->igi_nitems == 0)
4389 return EINVAL;
4390
4391 if (itp->igi_type != IPFGENITER_STATE)
4392 return EINVAL;
4393
4394 error = 0;
4395
4396 READ_ENTER(&ifs->ifs_ipf_state);
4397
4398 /*
4399 * Get "previous" entry from the token and find the next entry.
4400 */
4401 is = token->ipt_data;
4402 if (is == NULL) {
4403 next = ifs->ifs_ips_list;
4404 } else {
4405 next = is->is_next;
4406 }
4407
4408 dst = itp->igi_data;
4409 for (count = itp->igi_nitems; count > 0; count--) {
4410 /*
4411 * If we found an entry, add a reference to it and update the token.
4412 * Otherwise, zero out data to be returned and NULL out token.
4413 */
4414 if (next != NULL) {
4415 MUTEX_ENTER(&next->is_lock);
4416 next->is_ref++;
4417 MUTEX_EXIT(&next->is_lock);
4418 token->ipt_data = next;
4419 } else {
4420 bzero(&zero, sizeof(zero));
4421 next = &zero;
4422 token->ipt_data = NULL;
4423 }
4424
4425 /*
4426 * Safe to release lock now the we have a reference.
4427 */
4428 RWLOCK_EXIT(&ifs->ifs_ipf_state);
4429
4430 /*
4431 * Copy out data and clean up references and tokens.
4432 */
4433 error = COPYOUT(next, dst, sizeof(*next));
4434 if (error != 0)
4435 error = EFAULT;
4436 if (token->ipt_data == NULL) {
4437 ipf_freetoken(token, ifs);
4438 break;
4439 } else {
4440 if (is != NULL)
4441 fr_statederef(&is, ifs);
4442 if (next->is_next == NULL) {
4443 ipf_freetoken(token, ifs);
4444 break;
4445 }
4446 }
4447
4448 if ((count == 1) || (error != 0))
4449 break;
4450
4451 READ_ENTER(&ifs->ifs_ipf_state);
4452 dst += sizeof(*next);
4453 is = next;
4454 next = is->is_next;
4455 }
4456
4457 return error;
4458 }