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 RWLOCK_EXIT(&ifs->ifs_ipf_state);
1528 fin->fin_rev = IP6_NEQ(&is->is_dst, &fin->fin_daddr);
1529 fin->fin_flx |= FI_STATE;
1530 if (fin->fin_flx & FI_FRAG)
1531 (void) fr_newfrag(fin, pass ^ FR_KEEPSTATE);
1532
1533 return is;
1534 }
1535
1536
1537 /* ------------------------------------------------------------------------ */
1538 /* Function: fr_tcpoptions */
1539 /* Returns: int - 1 == packet matches state entry, 0 == it does not */
1540 /* Parameters: fin(I) - pointer to packet information */
1541 /* tcp(I) - pointer to TCP packet header */
1542 /* td(I) - pointer to TCP data held as part of the state */
1543 /* */
1544 /* Look after the TCP header for any options and deal with those that are */
1545 /* present. Record details about those that we recogise. */
1546 /* ------------------------------------------------------------------------ */
1547 static int fr_tcpoptions(fin, tcp, td)
1548 fr_info_t *fin;
1549 tcphdr_t *tcp;
1550 tcpdata_t *td;
1551 {
1552 int off, mlen, ol, i, len, retval;
1553 char buf[64], *s, opt;
1554 mb_t *m = NULL;
1555
1556 len = (TCP_OFF(tcp) << 2);
1557 if (fin->fin_dlen < len)
1558 return 0;
1559 len -= sizeof(*tcp);
1560
1561 off = fin->fin_plen - fin->fin_dlen + sizeof(*tcp) + fin->fin_ipoff;
1562
1563 m = fin->fin_m;
1564 mlen = MSGDSIZE(m) - off;
1565 if (len > mlen) {
1566 len = mlen;
1567 retval = 0;
1568 } else {
1569 retval = 1;
1570 }
1571
1572 COPYDATA(m, off, len, buf);
1573
1574 for (s = buf; len > 0; ) {
1575 opt = *s;
1576 if (opt == TCPOPT_EOL)
1577 break;
1578 else if (opt == TCPOPT_NOP)
1579 ol = 1;
1580 else {
1581 if (len < 2)
1582 break;
1583 ol = (int)*(s + 1);
1584 if (ol < 2 || ol > len)
1585 break;
1586
1587 /*
1588 * Extract the TCP options we are interested in out of
1589 * the header and store them in the the tcpdata struct.
1590 */
1591 switch (opt)
1592 {
1593 case TCPOPT_WINDOW :
1594 if (ol == TCPOLEN_WINDOW) {
1595 i = (int)*(s + 2);
1596 if (i > TCP_WSCALE_MAX)
1597 i = TCP_WSCALE_MAX;
1598 else if (i < 0)
1599 i = 0;
1600 td->td_winscale = i;
1601 td->td_winflags |= TCP_WSCALE_SEEN |
1602 TCP_WSCALE_FIRST;
1603 } else
1604 retval = -1;
1605 break;
1606 case TCPOPT_MAXSEG :
1607 /*
1608 * So, if we wanted to set the TCP MAXSEG,
1609 * it should be done here...
1610 */
1611 if (ol == TCPOLEN_MAXSEG) {
1612 i = (int)*(s + 2);
1613 i <<= 8;
1614 i += (int)*(s + 3);
1615 td->td_maxseg = i;
1616 } else
1617 retval = -1;
1618 break;
1619 case TCPOPT_SACK_PERMITTED :
1620 if (ol == TCPOLEN_SACK_PERMITTED)
1621 td->td_winflags |= TCP_SACK_PERMIT;
1622 else
1623 retval = -1;
1624 break;
1625 }
1626 }
1627 len -= ol;
1628 s += ol;
1629 }
1630 return retval;
1631 }
1632
1633
1634 /* ------------------------------------------------------------------------ */
1635 /* Function: fr_tcpstate */
1636 /* Returns: int - 1 == packet matches state entry, 0 == it does not */
1637 /* Parameters: fin(I) - pointer to packet information */
1638 /* tcp(I) - pointer to TCP packet header */
1639 /* is(I) - pointer to master state structure */
1640 /* */
1641 /* Check to see if a packet with TCP headers fits within the TCP window. */
1642 /* Change timeout depending on whether new packet is a SYN-ACK returning */
1643 /* for a SYN or a RST or FIN which indicate time to close up shop. */
1644 /* ------------------------------------------------------------------------ */
1645 static int fr_tcpstate(fin, tcp, is)
1646 fr_info_t *fin;
1647 tcphdr_t *tcp;
1648 ipstate_t *is;
1649 {
1650 int source, ret = 0, flags;
1651 tcpdata_t *fdata, *tdata;
1652 ipf_stack_t *ifs = fin->fin_ifs;
1653
1654 source = !fin->fin_rev;
1655 if (((is->is_flags & IS_TCPFSM) != 0) && (source == 1) &&
1656 (ntohs(is->is_sport) != fin->fin_data[0]))
1657 source = 0;
1658 fdata = &is->is_tcp.ts_data[!source];
1659 tdata = &is->is_tcp.ts_data[source];
1660
1661 MUTEX_ENTER(&is->is_lock);
1662
1663 /*
1664 * If a SYN packet is received for a connection that is in a half
1665 * closed state, then move its state entry to deletetq. In such case
1666 * the SYN packet will be consequently dropped. This allows new state
1667 * entry to be created with a retransmited SYN packet.
1668 */
1669 if ((tcp->th_flags & TH_OPENING) == TH_SYN) {
1670 if ((is->is_state[source] > IPF_TCPS_ESTABLISHED) &&
1671 (is->is_state[!source] > IPF_TCPS_ESTABLISHED)) {
1672 is->is_state[source] = IPF_TCPS_CLOSED;
1673 is->is_state[!source] = IPF_TCPS_CLOSED;
1674 /*
1675 * Do not update is->is_sti.tqe_die in case state entry
1676 * is already present in deletetq. It prevents state
1677 * entry ttl update by retransmitted SYN packets, which
1678 * may arrive before timer tick kicks off. The SYN
1679 * packet will be dropped again.
1680 */
1681 if (is->is_sti.tqe_ifq != &ifs->ifs_ips_deletetq)
1682 fr_movequeue(&is->is_sti, is->is_sti.tqe_ifq,
1683 &fin->fin_ifs->ifs_ips_deletetq,
1684 fin->fin_ifs);
1685
1686 MUTEX_EXIT(&is->is_lock);
1687 return 0;
1688 }
1689 }
1690
1691 if (fr_tcpinwindow(fin, fdata, tdata, tcp, is->is_flags)) {
1692 #ifdef IPFILTER_SCAN
1693 if (is->is_flags & (IS_SC_CLIENT|IS_SC_SERVER)) {
1694 ipsc_packet(fin, is);
1695 if (FR_ISBLOCK(is->is_pass)) {
1696 MUTEX_EXIT(&is->is_lock);
1697 return 1;
1698 }
1699 }
1700 #endif
1701
1702 /*
1703 * Nearing end of connection, start timeout.
1704 */
1705 ret = fr_tcp_age(&is->is_sti, fin, ifs->ifs_ips_tqtqb,
1706 is->is_flags);
1707 if (ret == 0) {
1708 MUTEX_EXIT(&is->is_lock);
1709 return 0;
1710 }
1711
1712 /*
1713 * set s0's as appropriate. Use syn-ack packet as it
1714 * contains both pieces of required information.
1715 */
1716 /*
1717 * Window scale option is only present in SYN/SYN-ACK packet.
1718 * Compare with ~TH_FIN to mask out T/TCP setups.
1719 */
1720 flags = tcp->th_flags & ~(TH_FIN|TH_ECNALL);
1721 if (flags == (TH_SYN|TH_ACK)) {
1722 is->is_s0[source] = ntohl(tcp->th_ack);
1723 is->is_s0[!source] = ntohl(tcp->th_seq) + 1;
1724 if (TCP_OFF(tcp) > (sizeof (tcphdr_t) >> 2)) {
1725 (void) fr_tcpoptions(fin, tcp, fdata);
1726 }
1727 if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN))
1728 fr_checknewisn(fin, is);
1729 } else if (flags == TH_SYN) {
1730 is->is_s0[source] = ntohl(tcp->th_seq) + 1;
1731 if ((TCP_OFF(tcp) > (sizeof(tcphdr_t) >> 2)))
1732 (void) fr_tcpoptions(fin, tcp, fdata);
1733
1734 if ((fin->fin_out != 0) && (is->is_pass & FR_NEWISN))
1735 fr_checknewisn(fin, is);
1736
1737 }
1738 ret = 1;
1739 } else
1740 fin->fin_flx |= FI_OOW;
1741 MUTEX_EXIT(&is->is_lock);
1742 return ret;
1743 }
1744
1745
1746 /* ------------------------------------------------------------------------ */
1747 /* Function: fr_checknewisn */
1748 /* Returns: Nil */
1749 /* Parameters: fin(I) - pointer to packet information */
1750 /* is(I) - pointer to master state structure */
1751 /* */
1752 /* Check to see if this TCP connection is expecting and needs a new */
1753 /* sequence number for a particular direction of the connection. */
1754 /* */
1755 /* NOTE: This does not actually change the sequence numbers, only gets new */
1756 /* one ready. */
1757 /* ------------------------------------------------------------------------ */
1758 static void fr_checknewisn(fin, is)
1759 fr_info_t *fin;
1760 ipstate_t *is;
1761 {
1762 u_32_t sumd, old, new;
1763 tcphdr_t *tcp;
1764 int i;
1765
1766 i = fin->fin_rev;
1767 tcp = fin->fin_dp;
1768
1769 if (((i == 0) && !(is->is_flags & IS_ISNSYN)) ||
1770 ((i == 1) && !(is->is_flags & IS_ISNACK))) {
1771 old = ntohl(tcp->th_seq);
1772 new = fr_newisn(fin);
1773 is->is_isninc[i] = new - old;
1774 CALC_SUMD(old, new, sumd);
1775 is->is_sumd[i] = (sumd & 0xffff) + (sumd >> 16);
1776
1777 is->is_flags |= ((i == 0) ? IS_ISNSYN : IS_ISNACK);
1778 }
1779 }
1780
1781
1782 /* ------------------------------------------------------------------------ */
1783 /* Function: fr_tcpinwindow */
1784 /* Returns: int - 1 == packet inside TCP "window", 0 == not inside. */
1785 /* Parameters: fin(I) - pointer to packet information */
1786 /* fdata(I) - pointer to tcp state informatio (forward) */
1787 /* tdata(I) - pointer to tcp state informatio (reverse) */
1788 /* tcp(I) - pointer to TCP packet header */
1789 /* */
1790 /* Given a packet has matched addresses and ports, check to see if it is */
1791 /* within the TCP data window. In a show of generosity, allow packets that */
1792 /* are within the window space behind the current sequence # as well. */
1793 /* ------------------------------------------------------------------------ */
1794 int fr_tcpinwindow(fin, fdata, tdata, tcp, flags)
1795 fr_info_t *fin;
1796 tcpdata_t *fdata, *tdata;
1797 tcphdr_t *tcp;
1798 int flags;
1799 {
1800 tcp_seq seq, ack, end;
1801 int ackskew, tcpflags;
1802 u_32_t win, maxwin;
1803 int dsize, inseq;
1804
1805 /*
1806 * Find difference between last checked packet and this packet.
1807 */
1808 tcpflags = tcp->th_flags;
1809 seq = ntohl(tcp->th_seq);
1810 ack = ntohl(tcp->th_ack);
1811
1812 if (tcpflags & TH_SYN)
1813 win = ntohs(tcp->th_win);
1814 else
1815 win = ntohs(tcp->th_win) << fdata->td_winscale;
1816
1817 /*
1818 * win 0 means the receiving endpoint has closed the window, because it
1819 * has not enough memory to receive data from sender. In such case we
1820 * are pretending window size to be 1 to let TCP probe data through.
1821 * TCP probe data can be either 0 or 1 octet of data, the RFC does not
1822 * state this accurately, so we have to allow 1 octet (win = 1) even if
1823 * the window is closed (win == 0).
1824 */
1825 if (win == 0)
1826 win = 1;
1827
1828 dsize = fin->fin_dlen - (TCP_OFF(tcp) << 2) +
1829 ((tcpflags & TH_SYN) ? 1 : 0) + ((tcpflags & TH_FIN) ? 1 : 0);
1830
1831 /*
1832 * if window scaling is present, the scaling is only allowed
1833 * for windows not in the first SYN packet. In that packet the
1834 * window is 65535 to specify the largest window possible
1835 * for receivers not implementing the window scale option.
1836 * Currently, we do not assume TTCP here. That means that
1837 * if we see a second packet from a host (after the initial
1838 * SYN), we can assume that the receiver of the SYN did
1839 * already send back the SYN/ACK (and thus that we know if
1840 * the receiver also does window scaling)
1841 */
1842 if (!(tcpflags & TH_SYN) && (fdata->td_winflags & TCP_WSCALE_FIRST)) {
1843 fdata->td_winflags &= ~TCP_WSCALE_FIRST;
1844 fdata->td_maxwin = win;
1845 }
1846
1847 end = seq + dsize;
1848
1849 if ((fdata->td_end == 0) &&
1850 (!(flags & IS_TCPFSM) ||
1851 ((tcpflags & TH_OPENING) == TH_OPENING))) {
1852 /*
1853 * Must be a (outgoing) SYN-ACK in reply to a SYN.
1854 */
1855 fdata->td_end = end - 1;
1856 fdata->td_maxwin = 1;
1857 fdata->td_maxend = end + win;
1858 }
1859
1860 if (!(tcpflags & TH_ACK)) { /* Pretend an ack was sent */
1861 ack = tdata->td_end;
1862 } else if (((tcpflags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) &&
1863 (ack == 0)) {
1864 /* gross hack to get around certain broken tcp stacks */
1865 ack = tdata->td_end;
1866 }
1867
1868 maxwin = tdata->td_maxwin;
1869 ackskew = tdata->td_end - ack;
1870
1871 /*
1872 * Strict sequencing only allows in-order delivery.
1873 */
1874 if ((flags & IS_STRICT) != 0) {
1875 if (seq != fdata->td_end) {
1876 DTRACE_PROBE(strict_check);
1877 return 0;
1878 }
1879 }
1880
1881 #define SEQ_GE(a,b) ((int)((a) - (b)) >= 0)
1882 #define SEQ_GT(a,b) ((int)((a) - (b)) > 0)
1883 inseq = 0;
1884 DTRACE_PROBE4(
1885 dyn_params,
1886 int, dsize,
1887 int, ackskew,
1888 int, maxwin,
1889 int, win
1890 );
1891 if (
1892 #if defined(_KERNEL)
1893 /*
1894 * end <-> s + n
1895 * maxend <-> ack + win
1896 * this is upperbound check
1897 */
1898 (SEQ_GE(fdata->td_maxend, end)) &&
1899 /*
1900 * this is lowerbound check
1901 */
1902 (SEQ_GE(seq, fdata->td_end - maxwin)) &&
1903 #endif
1904 /* XXX what about big packets */
1905 #define MAXACKWINDOW 66000
1906 (-ackskew <= (MAXACKWINDOW)) &&
1907 ( ackskew <= (MAXACKWINDOW << fdata->td_winscale))) {
1908 inseq = 1;
1909 /*
1910 * Microsoft Windows will send the next packet to the right of the
1911 * window if SACK is in use.
1912 */
1913 } else if ((seq == fdata->td_maxend) && (ackskew == 0) &&
1914 (fdata->td_winflags & TCP_SACK_PERMIT) &&
1915 (tdata->td_winflags & TCP_SACK_PERMIT)) {
1916 inseq = 1;
1917 /*
1918 * RST ACK with SEQ equal to 0 is sent by some OSes (i.e. Solaris) as a
1919 * response to initial SYN packet, when there is no application
1920 * listeing to on a port, where the SYN packet has came to.
1921 */
1922 } else if ((seq == 0) && (tcpflags == (TH_RST|TH_ACK)) &&
1923 (ackskew >= -1) && (ackskew <= 1)) {
1924 inseq = 1;
1925 } else if (!(flags & IS_TCPFSM)) {
1926
1927 if (!(fdata->td_winflags &
1928 (TCP_WSCALE_SEEN|TCP_WSCALE_FIRST))) {
1929 /*
1930 * No TCPFSM and no window scaling, so make some
1931 * extra guesses.
1932 */
1933 if ((seq == fdata->td_maxend) && (ackskew == 0))
1934 inseq = 1;
1935 else if (SEQ_GE(seq + maxwin, fdata->td_end - maxwin))
1936 inseq = 1;
1937 }
1938 }
1939
1940 if (inseq) {
1941 /* if ackskew < 0 then this should be due to fragmented
1942 * packets. There is no way to know the length of the
1943 * total packet in advance.
1944 * We do know the total length from the fragment cache though.
1945 * Note however that there might be more sessions with
1946 * exactly the same source and destination parameters in the
1947 * state cache (and source and destination is the only stuff
1948 * that is saved in the fragment cache). Note further that
1949 * some TCP connections in the state cache are hashed with
1950 * sport and dport as well which makes it not worthwhile to
1951 * look for them.
1952 * Thus, when ackskew is negative but still seems to belong
1953 * to this session, we bump up the destinations end value.
1954 */
1955 if (ackskew < 0) {
1956 DTRACE_PROBE2(end_update_td,
1957 int, tdata->td_end,
1958 int, ack
1959 );
1960 tdata->td_end = ack;
1961 }
1962
1963 /* update max window seen */
1964 if (fdata->td_maxwin < win) {
1965 DTRACE_PROBE2(win_update_fd,
1966 int, fdata->td_maxwin,
1967 int, win
1968 );
1969 fdata->td_maxwin = win;
1970 }
1971
1972 if (SEQ_GT(end, fdata->td_end)) {
1973 DTRACE_PROBE2(end_update_fd,
1974 int, fdata->td_end,
1975 int, end
1976 );
1977 fdata->td_end = end;
1978 }
1979
1980 if (SEQ_GE(ack + win, tdata->td_maxend)) {
1981 DTRACE_PROBE2(max_end_update_td,
1982 int, tdata->td_maxend,
1983 int, ack + win
1984 );
1985 tdata->td_maxend = ack + win;
1986 }
1987
1988 return 1;
1989 }
1990 fin->fin_flx |= FI_OOW;
1991
1992 #if defined(_KERNEL)
1993 if (!(SEQ_GE(seq, fdata->td_end - maxwin)))
1994 fin->fin_flx |= FI_NEG_OOW;
1995 #endif
1996
1997 return 0;
1998 }
1999
2000
2001 /* ------------------------------------------------------------------------ */
2002 /* Function: fr_stclone */
2003 /* Returns: ipstate_t* - NULL == cloning failed, */
2004 /* else pointer to new state structure */
2005 /* Parameters: fin(I) - pointer to packet information */
2006 /* tcp(I) - pointer to TCP/UDP header */
2007 /* is(I) - pointer to master state structure */
2008 /* */
2009 /* Create a "duplcate" state table entry from the master. */
2010 /* ------------------------------------------------------------------------ */
2011 static ipstate_t *fr_stclone(fin, tcp, is)
2012 fr_info_t *fin;
2013 tcphdr_t *tcp;
2014 ipstate_t *is;
2015 {
2016 ipstate_t *clone;
2017 u_32_t send;
2018 ipf_stack_t *ifs = fin->fin_ifs;
2019
2020 /*
2021 * Trigger automatic call to fr_state_flush() if the
2022 * table has reached capacity specified by hi watermark.
2023 */
2024 if (ST_TAB_WATER_LEVEL(ifs) > ifs->ifs_state_flush_level_hi)
2025 ifs->ifs_fr_state_doflush = 1;
2026
2027 /*
2028 * If automatic flushing did not do its job, and the table
2029 * has filled up, don't try to create a new entry. A NULL
2030 * return will indicate that the cloning has failed.
2031 */
2032 if (ifs->ifs_ips_num >= ifs->ifs_fr_statemax) {
2033 ATOMIC_INCL(ifs->ifs_ips_stats.iss_max);
2034 return NULL;
2035 }
2036
2037 KMALLOC(clone, ipstate_t *);
2038 if (clone == NULL)
2039 return NULL;
2040 bcopy((char *)is, (char *)clone, sizeof(*clone));
2041
2042 MUTEX_NUKE(&clone->is_lock);
2043
2044 clone->is_die = ONE_DAY + ifs->ifs_fr_ticks;
2045 clone->is_state[0] = 0;
2046 clone->is_state[1] = 0;
2047 send = ntohl(tcp->th_seq) + fin->fin_dlen - (TCP_OFF(tcp) << 2) +
2048 ((tcp->th_flags & TH_SYN) ? 1 : 0) +
2049 ((tcp->th_flags & TH_FIN) ? 1 : 0);
2050
2051 if (fin->fin_rev == 1) {
2052 clone->is_dend = send;
2053 clone->is_maxdend = send;
2054 clone->is_send = 0;
2055 clone->is_maxswin = 1;
2056 clone->is_maxdwin = ntohs(tcp->th_win);
2057 if (clone->is_maxdwin == 0)
2058 clone->is_maxdwin = 1;
2059 } else {
2060 clone->is_send = send;
2061 clone->is_maxsend = send;
2062 clone->is_dend = 0;
2063 clone->is_maxdwin = 1;
2064 clone->is_maxswin = ntohs(tcp->th_win);
2065 if (clone->is_maxswin == 0)
2066 clone->is_maxswin = 1;
2067 }
2068
2069 clone->is_flags &= ~SI_CLONE;
2070 clone->is_flags |= SI_CLONED;
2071 fr_stinsert(clone, fin->fin_rev, ifs);
2072 clone->is_ref = 1;
2073 if (clone->is_p == IPPROTO_TCP) {
2074 (void) fr_tcp_age(&clone->is_sti, fin, ifs->ifs_ips_tqtqb,
2075 clone->is_flags);
2076 }
2077 MUTEX_EXIT(&clone->is_lock);
2078 #ifdef IPFILTER_SCAN
2079 (void) ipsc_attachis(is);
2080 #endif
2081 #ifdef IPFILTER_SYNC
2082 if (is->is_flags & IS_STATESYNC)
2083 clone->is_sync = ipfsync_new(SMC_STATE, fin, clone);
2084 #endif
2085 return clone;
2086 }
2087
2088
2089 /* ------------------------------------------------------------------------ */
2090 /* Function: fr_matchsrcdst */
2091 /* Returns: Nil */
2092 /* Parameters: fin(I) - pointer to packet information */
2093 /* is(I) - pointer to state structure */
2094 /* src(I) - pointer to source address */
2095 /* dst(I) - pointer to destination address */
2096 /* tcp(I) - pointer to TCP/UDP header */
2097 /* */
2098 /* Match a state table entry against an IP packet. The logic below is that */
2099 /* ret gets set to one if the match succeeds, else remains 0. If it is */
2100 /* still 0 after the test. no match. */
2101 /* ------------------------------------------------------------------------ */
2102 static ipstate_t *fr_matchsrcdst(fin, is, src, dst, tcp, cmask)
2103 fr_info_t *fin;
2104 ipstate_t *is;
2105 i6addr_t *src, *dst;
2106 tcphdr_t *tcp;
2107 u_32_t cmask;
2108 {
2109 int ret = 0, rev, out, flags, flx = 0, idx;
2110 u_short sp, dp;
2111 u_32_t cflx;
2112 void *ifp;
2113 ipf_stack_t *ifs = fin->fin_ifs;
2114
2115 rev = IP6_NEQ(&is->is_dst, dst);
2116 ifp = fin->fin_ifp;
2117 out = fin->fin_out;
2118 flags = is->is_flags;
2119 sp = 0;
2120 dp = 0;
2121
2122 if (tcp != NULL) {
2123 sp = htons(fin->fin_sport);
2124 dp = ntohs(fin->fin_dport);
2125 }
2126 if (!rev) {
2127 if (tcp != NULL) {
2128 if (!(flags & SI_W_SPORT) && (sp != is->is_sport))
2129 rev = 1;
2130 else if (!(flags & SI_W_DPORT) && (dp != is->is_dport))
2131 rev = 1;
2132 }
2133 }
2134
2135 idx = (out << 1) + rev;
2136
2137 /*
2138 * If the interface for this 'direction' is set, make sure it matches.
2139 * An interface name that is not set matches any, as does a name of *.
2140 */
2141 if ((is->is_ifp[idx] == NULL &&
2142 (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '*')) ||
2143 is->is_ifp[idx] == ifp)
2144 ret = 1;
2145
2146 if (ret == 0) {
2147 DTRACE_PROBE(no_match_on_iface);
2148 return NULL;
2149 }
2150 ret = 0;
2151
2152 /*
2153 * Match addresses and ports.
2154 */
2155 if (rev == 0) {
2156 if ((IP6_EQ(&is->is_dst, dst) || (flags & SI_W_DADDR)) &&
2157 (IP6_EQ(&is->is_src, src) || (flags & SI_W_SADDR))) {
2158 if (tcp) {
2159 if ((sp == is->is_sport || flags & SI_W_SPORT)&&
2160 (dp == is->is_dport || flags & SI_W_DPORT))
2161 ret = 1;
2162 } else {
2163 ret = 1;
2164 }
2165 }
2166 } else {
2167 if ((IP6_EQ(&is->is_dst, src) || (flags & SI_W_DADDR)) &&
2168 (IP6_EQ(&is->is_src, dst) || (flags & SI_W_SADDR))) {
2169 if (tcp) {
2170 if ((dp == is->is_sport || flags & SI_W_SPORT)&&
2171 (sp == is->is_dport || flags & SI_W_DPORT))
2172 ret = 1;
2173 } else {
2174 ret = 1;
2175 }
2176 }
2177 }
2178
2179 if (ret == 0) {
2180 DTRACE_PROBE(no_match_on_addrs);
2181 return NULL;
2182 }
2183 /*
2184 * Whether or not this should be here, is questionable, but the aim
2185 * is to get this out of the main line.
2186 */
2187 if (tcp == NULL)
2188 flags = is->is_flags & ~(SI_WILDP|SI_NEWFR|SI_CLONE|SI_CLONED);
2189
2190 /*
2191 * Only one of the source or destination address can be flaged as a
2192 * wildcard. Fill in the missing address, if set.
2193 * For IPv6, if the address being copied in is multicast, then
2194 * don't reset the wild flag - multicast causes it to be set in the
2195 * first place!
2196 */
2197 if ((flags & (SI_W_SADDR|SI_W_DADDR))) {
2198 fr_ip_t *fi = &fin->fin_fi;
2199
2200 if ((flags & SI_W_SADDR) != 0) {
2201 if (rev == 0) {
2202 #ifdef USE_INET6
2203 if (is->is_v == 6 &&
2204 IN6_IS_ADDR_MULTICAST(&fi->fi_src.in6))
2205 /*EMPTY*/;
2206 else
2207 #endif
2208 {
2209 is->is_src = fi->fi_src;
2210 is->is_flags &= ~SI_W_SADDR;
2211 }
2212 } else {
2213 #ifdef USE_INET6
2214 if (is->is_v == 6 &&
2215 IN6_IS_ADDR_MULTICAST(&fi->fi_dst.in6))
2216 /*EMPTY*/;
2217 else
2218 #endif
2219 {
2220 is->is_src = fi->fi_dst;
2221 is->is_flags &= ~SI_W_SADDR;
2222 }
2223 }
2224 } else if ((flags & SI_W_DADDR) != 0) {
2225 if (rev == 0) {
2226 #ifdef USE_INET6
2227 if (is->is_v == 6 &&
2228 IN6_IS_ADDR_MULTICAST(&fi->fi_dst.in6))
2229 /*EMPTY*/;
2230 else
2231 #endif
2232 {
2233 is->is_dst = fi->fi_dst;
2234 is->is_flags &= ~SI_W_DADDR;
2235 }
2236 } else {
2237 #ifdef USE_INET6
2238 if (is->is_v == 6 &&
2239 IN6_IS_ADDR_MULTICAST(&fi->fi_src.in6))
2240 /*EMPTY*/;
2241 else
2242 #endif
2243 {
2244 is->is_dst = fi->fi_src;
2245 is->is_flags &= ~SI_W_DADDR;
2246 }
2247 }
2248 }
2249 if ((is->is_flags & (SI_WILDA|SI_WILDP)) == 0) {
2250 ATOMIC_DECL(ifs->ifs_ips_stats.iss_wild);
2251 }
2252 }
2253
2254 flx = fin->fin_flx & cmask;
2255 cflx = is->is_flx[out][rev];
2256
2257 /*
2258 * Match up any flags set from IP options.
2259 */
2260 if ((cflx && (flx != (cflx & cmask))) ||
2261 ((fin->fin_optmsk & is->is_optmsk[rev]) != is->is_opt[rev]) ||
2262 ((fin->fin_secmsk & is->is_secmsk) != is->is_sec) ||
2263 ((fin->fin_auth & is->is_authmsk) != is->is_auth)) {
2264 DTRACE_PROBE4(no_match_on_flags,
2265 int, (cflx && (flx != (cflx & cmask))),
2266 int,
2267 ((fin->fin_optmsk & is->is_optmsk[rev]) != is->is_opt[rev]),
2268 int, ((fin->fin_secmsk & is->is_secmsk) != is->is_sec),
2269 int, ((fin->fin_auth & is->is_authmsk) != is->is_auth)
2270 );
2271 return NULL;
2272 }
2273 /*
2274 * Only one of the source or destination port can be flagged as a
2275 * wildcard. When filling it in, fill in a copy of the matched entry
2276 * if it has the cloning flag set.
2277 */
2278 if ((fin->fin_flx & FI_IGNORE) != 0) {
2279 fin->fin_rev = rev;
2280 return is;
2281 }
2282
2283 if ((flags & (SI_W_SPORT|SI_W_DPORT))) {
2284 if ((flags & SI_CLONE) != 0) {
2285 ipstate_t *clone;
2286
2287 clone = fr_stclone(fin, tcp, is);
2288 if (clone == NULL)
2289 return NULL;
2290 is = clone;
2291 } else {
2292 ATOMIC_DECL(ifs->ifs_ips_stats.iss_wild);
2293 }
2294
2295 if ((flags & SI_W_SPORT) != 0) {
2296 if (rev == 0) {
2297 is->is_sport = sp;
2298 is->is_send = ntohl(tcp->th_seq);
2299 } else {
2300 is->is_sport = dp;
2301 is->is_send = ntohl(tcp->th_ack);
2302 }
2303 is->is_maxsend = is->is_send + 1;
2304 } else if ((flags & SI_W_DPORT) != 0) {
2305 if (rev == 0) {
2306 is->is_dport = dp;
2307 is->is_dend = ntohl(tcp->th_ack);
2308 } else {
2309 is->is_dport = sp;
2310 is->is_dend = ntohl(tcp->th_seq);
2311 }
2312 is->is_maxdend = is->is_dend + 1;
2313 }
2314 is->is_flags &= ~(SI_W_SPORT|SI_W_DPORT);
2315 if ((flags & SI_CLONED) && ifs->ifs_ipstate_logging)
2316 ipstate_log(is, ISL_CLONE, ifs);
2317 }
2318
2319 ret = -1;
2320
2321 if (is->is_flx[out][rev] == 0) {
2322 is->is_flx[out][rev] = flx;
2323 /*
2324 * If we are dealing with the first packet coming in reverse
2325 * direction (sent by peer), then we have to set options into
2326 * state.
2327 */
2328 if (rev == 1 && is->is_optmsk[1] == 0x0) {
2329 is->is_optmsk[1] = 0xffffffff;
2330 is->is_opt[1] = fin->fin_optmsk;
2331 DTRACE_PROBE(set_rev_opts);
2332 }
2333 if (is->is_v == 6) {
2334 is->is_opt[rev] &= ~0x8;
2335 is->is_optmsk[rev] &= ~0x8;
2336 }
2337 }
2338
2339 /*
2340 * Check if the interface name for this "direction" is set and if not,
2341 * fill it in.
2342 */
2343 if (is->is_ifp[idx] == NULL &&
2344 (*is->is_ifname[idx] == '\0' || *is->is_ifname[idx] == '*')) {
2345 is->is_ifp[idx] = ifp;
2346 COPYIFNAME(ifp, is->is_ifname[idx], fin->fin_v);
2347 }
2348 fin->fin_rev = rev;
2349 return is;
2350 }
2351
2352
2353 /* ------------------------------------------------------------------------ */
2354 /* Function: fr_checkicmpmatchingstate */
2355 /* Returns: Nil */
2356 /* Parameters: fin(I) - pointer to packet information */
2357 /* */
2358 /* If we've got an ICMP error message, using the information stored in the */
2359 /* ICMP packet, look for a matching state table entry. */
2360 /* */
2361 /* If we return NULL then no lock on ipf_state is held. */
2362 /* If we return non-null then a read-lock on ipf_state is held. */
2363 /* ------------------------------------------------------------------------ */
2364 static ipstate_t *fr_checkicmpmatchingstate(fin)
2365 fr_info_t *fin;
2366 {
2367 ipstate_t *is, **isp;
2368 u_short sport, dport;
2369 u_char pr;
2370 int backward, i, oi;
2371 i6addr_t dst, src;
2372 struct icmp *ic;
2373 u_short savelen;
2374 icmphdr_t *icmp;
2375 fr_info_t ofin;
2376 tcphdr_t *tcp;
2377 int len;
2378 ip_t *oip;
2379 u_int hv;
2380 ipf_stack_t *ifs = fin->fin_ifs;
2381
2382 /*
2383 * Does it at least have the return (basic) IP header ?
2384 * Is it an actual recognised ICMP error type?
2385 * Only a basic IP header (no options) should be with
2386 * an ICMP error header.
2387 */
2388 if ((fin->fin_v != 4) || (fin->fin_hlen != sizeof(ip_t)) ||
2389 (fin->fin_plen < ICMPERR_MINPKTLEN) ||
2390 !(fin->fin_flx & FI_ICMPERR))
2391 return NULL;
2392 ic = fin->fin_dp;
2393
2394 oip = (ip_t *)((char *)ic + ICMPERR_ICMPHLEN);
2395 /*
2396 * Check if the at least the old IP header (with options) and
2397 * 8 bytes of payload is present.
2398 */
2399 if (fin->fin_plen < ICMPERR_MAXPKTLEN + ((IP_HL(oip) - 5) << 2))
2400 return NULL;
2401
2402 /*
2403 * Sanity Checks.
2404 */
2405 len = fin->fin_dlen - ICMPERR_ICMPHLEN;
2406 if ((len <= 0) || ((IP_HL(oip) << 2) > len))
2407 return NULL;
2408
2409 /*
2410 * Is the buffer big enough for all of it ? It's the size of the IP
2411 * header claimed in the encapsulated part which is of concern. It
2412 * may be too big to be in this buffer but not so big that it's
2413 * outside the ICMP packet, leading to TCP deref's causing problems.
2414 * This is possible because we don't know how big oip_hl is when we
2415 * do the pullup early in fr_check() and thus can't guarantee it is
2416 * all here now.
2417 */
2418 #ifdef _KERNEL
2419 {
2420 mb_t *m;
2421
2422 m = fin->fin_m;
2423 # if defined(MENTAT)
2424 if ((char *)oip + len > (char *)m->b_wptr)
2425 return NULL;
2426 # else
2427 if ((char *)oip + len > (char *)fin->fin_ip + m->m_len)
2428 return NULL;
2429 # endif
2430 }
2431 #endif
2432 bcopy((char *)fin, (char *)&ofin, sizeof(*fin));
2433
2434 /*
2435 * in the IPv4 case we must zero the i6addr union otherwise
2436 * the IP6_EQ and IP6_NEQ macros produce the wrong results because
2437 * of the 'junk' in the unused part of the union
2438 */
2439 bzero((char *)&src, sizeof(src));
2440 bzero((char *)&dst, sizeof(dst));
2441
2442 /*
2443 * we make an fin entry to be able to feed it to
2444 * matchsrcdst note that not all fields are encessary
2445 * but this is the cleanest way. Note further we fill
2446 * in fin_mp such that if someone uses it we'll get
2447 * a kernel panic. fr_matchsrcdst does not use this.
2448 *
2449 * watch out here, as ip is in host order and oip in network
2450 * order. Any change we make must be undone afterwards, like
2451 * oip->ip_off - it is still in network byte order so fix it.
2452 */
2453 savelen = oip->ip_len;
2454 oip->ip_len = len;
2455 oip->ip_off = ntohs(oip->ip_off);
2456
2457 ofin.fin_flx = FI_NOCKSUM;
2458 ofin.fin_v = 4;
2459 ofin.fin_ip = oip;
2460 ofin.fin_m = NULL; /* if dereferenced, panic XXX */
2461 ofin.fin_mp = NULL; /* if dereferenced, panic XXX */
2462 ofin.fin_plen = fin->fin_dlen - ICMPERR_ICMPHLEN;
2463 (void) fr_makefrip(IP_HL(oip) << 2, oip, &ofin);
2464 ofin.fin_ifp = fin->fin_ifp;
2465 ofin.fin_out = !fin->fin_out;
2466 /*
2467 * Reset the short and bad flag here because in fr_matchsrcdst()
2468 * the flags for the current packet (fin_flx) are compared against
2469 * those for the existing session.
2470 */
2471 ofin.fin_flx &= ~(FI_BAD|FI_SHORT);
2472
2473 /*
2474 * Put old values of ip_len and ip_off back as we don't know
2475 * if we have to forward the packet (or process it again.
2476 */
2477 oip->ip_len = savelen;
2478 oip->ip_off = htons(oip->ip_off);
2479
2480 switch (oip->ip_p)
2481 {
2482 case IPPROTO_ICMP :
2483 /*
2484 * an ICMP error can only be generated as a result of an
2485 * ICMP query, not as the response on an ICMP error
2486 *
2487 * XXX theoretically ICMP_ECHOREP and the other reply's are
2488 * ICMP query's as well, but adding them here seems strange XXX
2489 */
2490 if ((ofin.fin_flx & FI_ICMPERR) != 0)
2491 return NULL;
2492
2493 /*
2494 * perform a lookup of the ICMP packet in the state table
2495 */
2496 icmp = (icmphdr_t *)((char *)oip + (IP_HL(oip) << 2));
2497 hv = (pr = oip->ip_p);
2498 src.in4 = oip->ip_src;
2499 hv += src.in4.s_addr;
2500 dst.in4 = oip->ip_dst;
2501 hv += dst.in4.s_addr;
2502 hv += icmp->icmp_id;
2503 hv = DOUBLE_HASH(hv, ifs);
2504
2505 READ_ENTER(&ifs->ifs_ipf_state);
2506 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) {
2507 isp = &is->is_hnext;
2508 if ((is->is_p != pr) || (is->is_v != 4))
2509 continue;
2510 if (is->is_pass & FR_NOICMPERR)
2511 continue;
2512 is = fr_matchsrcdst(&ofin, is, &src, &dst,
2513 NULL, FI_ICMPCMP);
2514 if (is != NULL) {
2515 if ((is->is_pass & FR_NOICMPERR) != 0) {
2516 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2517 return NULL;
2518 }
2519 /*
2520 * i : the index of this packet (the icmp
2521 * unreachable)
2522 * oi : the index of the original packet found
2523 * in the icmp header (i.e. the packet
2524 * causing this icmp)
2525 * backward : original packet was backward
2526 * compared to the state
2527 */
2528 backward = IP6_NEQ(&is->is_src, &src);
2529 fin->fin_rev = !backward;
2530 i = (!backward << 1) + fin->fin_out;
2531 oi = (backward << 1) + ofin.fin_out;
2532 if (is->is_icmppkts[i] > is->is_pkts[oi])
2533 continue;
2534 ifs->ifs_ips_stats.iss_hits++;
2535 is->is_icmppkts[i]++;
2536 return is;
2537 }
2538 }
2539 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2540 return NULL;
2541 case IPPROTO_TCP :
2542 case IPPROTO_UDP :
2543 break;
2544 default :
2545 return NULL;
2546 }
2547
2548 tcp = (tcphdr_t *)((char *)oip + (IP_HL(oip) << 2));
2549 dport = tcp->th_dport;
2550 sport = tcp->th_sport;
2551
2552 hv = (pr = oip->ip_p);
2553 src.in4 = oip->ip_src;
2554 hv += src.in4.s_addr;
2555 dst.in4 = oip->ip_dst;
2556 hv += dst.in4.s_addr;
2557 hv += dport;
2558 hv += sport;
2559 hv = DOUBLE_HASH(hv, ifs);
2560
2561 READ_ENTER(&ifs->ifs_ipf_state);
2562 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) {
2563 isp = &is->is_hnext;
2564 /*
2565 * Only allow this icmp though if the
2566 * encapsulated packet was allowed through the
2567 * other way around. Note that the minimal amount
2568 * of info present does not allow for checking against
2569 * tcp internals such as seq and ack numbers. Only the
2570 * ports are known to be present and can be even if the
2571 * short flag is set.
2572 */
2573 if ((is->is_p == pr) && (is->is_v == 4) &&
2574 (is = fr_matchsrcdst(&ofin, is, &src, &dst,
2575 tcp, FI_ICMPCMP))) {
2576 /*
2577 * i : the index of this packet (the icmp unreachable)
2578 * oi : the index of the original packet found in the
2579 * icmp header (i.e. the packet causing this icmp)
2580 * backward : original packet was backward compared to
2581 * the state
2582 */
2583 backward = IP6_NEQ(&is->is_src, &src);
2584 fin->fin_rev = !backward;
2585 i = (!backward << 1) + fin->fin_out;
2586 oi = (backward << 1) + ofin.fin_out;
2587
2588 if (((is->is_pass & FR_NOICMPERR) != 0) ||
2589 (is->is_icmppkts[i] > is->is_pkts[oi]))
2590 break;
2591 ifs->ifs_ips_stats.iss_hits++;
2592 is->is_icmppkts[i]++;
2593 /*
2594 * we deliberately do not touch the timeouts
2595 * for the accompanying state table entry.
2596 * It remains to be seen if that is correct. XXX
2597 */
2598 return is;
2599 }
2600 }
2601 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2602 return NULL;
2603 }
2604
2605
2606 /* ------------------------------------------------------------------------ */
2607 /* Function: fr_ipsmove */
2608 /* Returns: Nil */
2609 /* Parameters: is(I) - pointer to state table entry */
2610 /* hv(I) - new hash value for state table entry */
2611 /* Write Locks: ipf_state */
2612 /* */
2613 /* Move a state entry from one position in the hash table to another. */
2614 /* ------------------------------------------------------------------------ */
2615 static void fr_ipsmove(is, hv, ifs)
2616 ipstate_t *is;
2617 u_int hv;
2618 ipf_stack_t *ifs;
2619 {
2620 ipstate_t **isp;
2621 u_int hvm;
2622
2623 ASSERT(rw_read_locked(&ifs->ifs_ipf_state.ipf_lk) == 0);
2624
2625 hvm = is->is_hv;
2626 /*
2627 * Remove the hash from the old location...
2628 */
2629 isp = is->is_phnext;
2630 if (is->is_hnext)
2631 is->is_hnext->is_phnext = isp;
2632 *isp = is->is_hnext;
2633 if (ifs->ifs_ips_table[hvm] == NULL)
2634 ifs->ifs_ips_stats.iss_inuse--;
2635 ifs->ifs_ips_stats.iss_bucketlen[hvm]--;
2636
2637 /*
2638 * ...and put the hash in the new one.
2639 */
2640 hvm = DOUBLE_HASH(hv, ifs);
2641 is->is_hv = hvm;
2642 isp = &ifs->ifs_ips_table[hvm];
2643 if (*isp)
2644 (*isp)->is_phnext = &is->is_hnext;
2645 else
2646 ifs->ifs_ips_stats.iss_inuse++;
2647 ifs->ifs_ips_stats.iss_bucketlen[hvm]++;
2648 is->is_phnext = isp;
2649 is->is_hnext = *isp;
2650 *isp = is;
2651 }
2652
2653
2654 /* ------------------------------------------------------------------------ */
2655 /* Function: fr_stlookup */
2656 /* Returns: ipstate_t* - NULL == no matching state found, */
2657 /* else pointer to state information is returned */
2658 /* Parameters: fin(I) - pointer to packet information */
2659 /* tcp(I) - pointer to TCP/UDP header. */
2660 /* */
2661 /* Search the state table for a matching entry to the packet described by */
2662 /* the contents of *fin. */
2663 /* */
2664 /* If we return NULL then no lock on ipf_state is held. */
2665 /* If we return non-null then a read-lock on ipf_state is held. */
2666 /* ------------------------------------------------------------------------ */
2667 ipstate_t *fr_stlookup(fin, tcp, ifqp)
2668 fr_info_t *fin;
2669 tcphdr_t *tcp;
2670 ipftq_t **ifqp;
2671 {
2672 u_int hv, hvm, pr, v, tryagain;
2673 ipstate_t *is, **isp;
2674 u_short dport, sport;
2675 i6addr_t src, dst;
2676 struct icmp *ic;
2677 ipftq_t *ifq;
2678 int oow;
2679 ipf_stack_t *ifs = fin->fin_ifs;
2680
2681 is = NULL;
2682 ifq = NULL;
2683 tcp = fin->fin_dp;
2684 ic = (struct icmp *)tcp;
2685 hv = (pr = fin->fin_fi.fi_p);
2686 src = fin->fin_fi.fi_src;
2687 dst = fin->fin_fi.fi_dst;
2688 hv += src.in4.s_addr;
2689 hv += dst.in4.s_addr;
2690
2691 v = fin->fin_fi.fi_v;
2692 #ifdef USE_INET6
2693 if (v == 6) {
2694 hv += fin->fin_fi.fi_src.i6[1];
2695 hv += fin->fin_fi.fi_src.i6[2];
2696 hv += fin->fin_fi.fi_src.i6[3];
2697
2698 if ((fin->fin_p == IPPROTO_ICMPV6) &&
2699 IN6_IS_ADDR_MULTICAST(&fin->fin_fi.fi_dst.in6)) {
2700 hv -= dst.in4.s_addr;
2701 } else {
2702 hv += fin->fin_fi.fi_dst.i6[1];
2703 hv += fin->fin_fi.fi_dst.i6[2];
2704 hv += fin->fin_fi.fi_dst.i6[3];
2705 }
2706 }
2707 #endif
2708 if ((v == 4) &&
2709 (fin->fin_flx & (FI_MULTICAST|FI_BROADCAST|FI_MBCAST))) {
2710 if (fin->fin_out == 0) {
2711 hv -= src.in4.s_addr;
2712 } else {
2713 hv -= dst.in4.s_addr;
2714 }
2715 }
2716
2717 /*
2718 * Search the hash table for matching packet header info.
2719 */
2720 switch (pr)
2721 {
2722 #ifdef USE_INET6
2723 case IPPROTO_ICMPV6 :
2724 tryagain = 0;
2725 if (v == 6) {
2726 if ((ic->icmp_type == ICMP6_ECHO_REQUEST) ||
2727 (ic->icmp_type == ICMP6_ECHO_REPLY)) {
2728 hv += ic->icmp_id;
2729 }
2730 }
2731 READ_ENTER(&ifs->ifs_ipf_state);
2732 icmp6again:
2733 hvm = DOUBLE_HASH(hv, ifs);
2734 for (isp = &ifs->ifs_ips_table[hvm]; ((is = *isp) != NULL); ) {
2735 isp = &is->is_hnext;
2736 if ((is->is_p != pr) || (is->is_v != v))
2737 continue;
2738 is = fr_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP);
2739 if (is != NULL &&
2740 fr_matchicmpqueryreply(v, &is->is_icmp,
2741 ic, fin->fin_rev)) {
2742 if (fin->fin_rev)
2743 ifq = &ifs->ifs_ips_icmpacktq;
2744 else
2745 ifq = &ifs->ifs_ips_icmptq;
2746 break;
2747 }
2748 }
2749
2750 if (is != NULL) {
2751 if ((tryagain != 0) && !(is->is_flags & SI_W_DADDR)) {
2752 hv += fin->fin_fi.fi_src.i6[0];
2753 hv += fin->fin_fi.fi_src.i6[1];
2754 hv += fin->fin_fi.fi_src.i6[2];
2755 hv += fin->fin_fi.fi_src.i6[3];
2756 fr_ipsmove(is, hv, ifs);
2757 MUTEX_DOWNGRADE(&ifs->ifs_ipf_state);
2758 }
2759 break;
2760 }
2761 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2762
2763 /*
2764 * No matching icmp state entry. Perhaps this is a
2765 * response to another state entry.
2766 *
2767 * XXX With some ICMP6 packets, the "other" address is already
2768 * in the packet, after the ICMP6 header, and this could be
2769 * used in place of the multicast address. However, taking
2770 * advantage of this requires some significant code changes
2771 * to handle the specific types where that is the case.
2772 */
2773 if ((ifs->ifs_ips_stats.iss_wild != 0) && (v == 6) && (tryagain == 0) &&
2774 !IN6_IS_ADDR_MULTICAST(&fin->fin_fi.fi_src.in6)) {
2775 hv -= fin->fin_fi.fi_src.i6[0];
2776 hv -= fin->fin_fi.fi_src.i6[1];
2777 hv -= fin->fin_fi.fi_src.i6[2];
2778 hv -= fin->fin_fi.fi_src.i6[3];
2779 tryagain = 1;
2780 WRITE_ENTER(&ifs->ifs_ipf_state);
2781 goto icmp6again;
2782 }
2783
2784 is = fr_checkicmp6matchingstate(fin);
2785 if (is != NULL)
2786 return is;
2787 break;
2788 #endif
2789
2790 case IPPROTO_ICMP :
2791 if (v == 4) {
2792 hv += ic->icmp_id;
2793 }
2794 hv = DOUBLE_HASH(hv, ifs);
2795 READ_ENTER(&ifs->ifs_ipf_state);
2796 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) {
2797 isp = &is->is_hnext;
2798 if ((is->is_p != pr) || (is->is_v != v))
2799 continue;
2800 is = fr_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP);
2801 if (is != NULL &&
2802 fr_matchicmpqueryreply(v, &is->is_icmp,
2803 ic, fin->fin_rev)) {
2804 if (fin->fin_rev)
2805 ifq = &ifs->ifs_ips_icmpacktq;
2806 else
2807 ifq = &ifs->ifs_ips_icmptq;
2808 break;
2809 }
2810 }
2811 if (is == NULL) {
2812 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2813 }
2814 break;
2815
2816 case IPPROTO_TCP :
2817 case IPPROTO_UDP :
2818 ifqp = NULL;
2819 sport = htons(fin->fin_data[0]);
2820 hv += sport;
2821 dport = htons(fin->fin_data[1]);
2822 hv += dport;
2823 oow = 0;
2824 tryagain = 0;
2825 READ_ENTER(&ifs->ifs_ipf_state);
2826 retry_tcpudp:
2827 hvm = DOUBLE_HASH(hv, ifs);
2828 for (isp = &ifs->ifs_ips_table[hvm]; ((is = *isp) != NULL); ) {
2829 isp = &is->is_hnext;
2830 if ((is->is_p != pr) || (is->is_v != v))
2831 continue;
2832 fin->fin_flx &= ~FI_OOW;
2833 is = fr_matchsrcdst(fin, is, &src, &dst, tcp, FI_CMP);
2834 if (is != NULL) {
2835 if (pr == IPPROTO_TCP) {
2836 if (!fr_tcpstate(fin, tcp, is)) {
2837 oow |= fin->fin_flx & FI_OOW;
2838 continue;
2839 }
2840 }
2841 break;
2842 }
2843 }
2844 if (is != NULL) {
2845 if (tryagain &&
2846 !(is->is_flags & (SI_CLONE|SI_WILDP|SI_WILDA))) {
2847 hv += dport;
2848 hv += sport;
2849 fr_ipsmove(is, hv, ifs);
2850 MUTEX_DOWNGRADE(&ifs->ifs_ipf_state);
2851 }
2852 break;
2853 }
2854 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2855
2856 if (ifs->ifs_ips_stats.iss_wild) {
2857 if (tryagain == 0) {
2858 hv -= dport;
2859 hv -= sport;
2860 } else if (tryagain == 1) {
2861 hv = fin->fin_fi.fi_p;
2862 /*
2863 * If we try to pretend this is a reply to a
2864 * multicast/broadcast packet then we need to
2865 * exclude part of the address from the hash
2866 * calculation.
2867 */
2868 if (fin->fin_out == 0) {
2869 hv += src.in4.s_addr;
2870 } else {
2871 hv += dst.in4.s_addr;
2872 }
2873 hv += dport;
2874 hv += sport;
2875 }
2876 tryagain++;
2877 if (tryagain <= 2) {
2878 WRITE_ENTER(&ifs->ifs_ipf_state);
2879 goto retry_tcpudp;
2880 }
2881 }
2882 fin->fin_flx |= oow;
2883 break;
2884
2885 #if 0
2886 case IPPROTO_GRE :
2887 gre = fin->fin_dp;
2888 if (GRE_REV(gre->gr_flags) == 1) {
2889 hv += gre->gr_call;
2890 }
2891 /* FALLTHROUGH */
2892 #endif
2893 default :
2894 ifqp = NULL;
2895 hvm = DOUBLE_HASH(hv, ifs);
2896 READ_ENTER(&ifs->ifs_ipf_state);
2897 for (isp = &ifs->ifs_ips_table[hvm]; ((is = *isp) != NULL); ) {
2898 isp = &is->is_hnext;
2899 if ((is->is_p != pr) || (is->is_v != v))
2900 continue;
2901 is = fr_matchsrcdst(fin, is, &src, &dst, NULL, FI_CMP);
2902 if (is != NULL) {
2903 ifq = &ifs->ifs_ips_iptq;
2904 break;
2905 }
2906 }
2907 if (is == NULL) {
2908 RWLOCK_EXIT(&ifs->ifs_ipf_state);
2909 }
2910 break;
2911 }
2912
2913 if ((is != NULL) && ((is->is_sti.tqe_flags & TQE_RULEBASED) != 0) &&
2914 (is->is_tqehead[fin->fin_rev] != NULL))
2915 ifq = is->is_tqehead[fin->fin_rev];
2916 if (ifq != NULL && ifqp != NULL)
2917 *ifqp = ifq;
2918 return is;
2919 }
2920
2921
2922 /* ------------------------------------------------------------------------ */
2923 /* Function: fr_updatestate */
2924 /* Returns: Nil */
2925 /* Parameters: fin(I) - pointer to packet information */
2926 /* is(I) - pointer to state table entry */
2927 /* Read Locks: ipf_state */
2928 /* */
2929 /* Updates packet and byte counters for a newly received packet. Seeds the */
2930 /* fragment cache with a new entry as required. */
2931 /* ------------------------------------------------------------------------ */
2932 void fr_updatestate(fin, is, ifq)
2933 fr_info_t *fin;
2934 ipstate_t *is;
2935 ipftq_t *ifq;
2936 {
2937 ipftqent_t *tqe;
2938 int i, pass;
2939 ipf_stack_t *ifs = fin->fin_ifs;
2940
2941 i = (fin->fin_rev << 1) + fin->fin_out;
2942
2943 /*
2944 * For TCP packets, ifq == NULL. For all others, check if this new
2945 * queue is different to the last one it was on and move it if so.
2946 */
2947 tqe = &is->is_sti;
2948 MUTEX_ENTER(&is->is_lock);
2949 if ((tqe->tqe_flags & TQE_RULEBASED) != 0)
2950 ifq = is->is_tqehead[fin->fin_rev];
2951
2952 if (ifq != NULL)
2953 fr_movequeue(tqe, tqe->tqe_ifq, ifq, ifs);
2954
2955 is->is_pkts[i]++;
2956 fin->fin_pktnum = is->is_pkts[i] + is->is_icmppkts[i];
2957 is->is_bytes[i] += fin->fin_plen;
2958 MUTEX_EXIT(&is->is_lock);
2959
2960 #ifdef IPFILTER_SYNC
2961 if (is->is_flags & IS_STATESYNC)
2962 ipfsync_update(SMC_STATE, fin, is->is_sync);
2963 #endif
2964
2965 ATOMIC_INCL(ifs->ifs_ips_stats.iss_hits);
2966
2967 fin->fin_fr = is->is_rule;
2968
2969 /*
2970 * If this packet is a fragment and the rule says to track fragments,
2971 * then create a new fragment cache entry.
2972 */
2973 pass = is->is_pass;
2974 if ((fin->fin_flx & FI_FRAG) && FR_ISPASS(pass))
2975 (void) fr_newfrag(fin, pass ^ FR_KEEPSTATE);
2976 }
2977
2978
2979 /* ------------------------------------------------------------------------ */
2980 /* Function: fr_checkstate */
2981 /* Returns: frentry_t* - NULL == search failed, */
2982 /* else pointer to rule for matching state */
2983 /* Parameters: ifp(I) - pointer to interface */
2984 /* passp(I) - pointer to filtering result flags */
2985 /* */
2986 /* Check if a packet is associated with an entry in the state table. */
2987 /* ------------------------------------------------------------------------ */
2988 frentry_t *fr_checkstate(fin, passp)
2989 fr_info_t *fin;
2990 u_32_t *passp;
2991 {
2992 ipstate_t *is;
2993 frentry_t *fr;
2994 tcphdr_t *tcp;
2995 ipftq_t *ifq;
2996 u_int pass;
2997 ipf_stack_t *ifs = fin->fin_ifs;
2998
2999 if (ifs->ifs_fr_state_lock || (ifs->ifs_ips_list == NULL) ||
3000 (fin->fin_flx & (FI_SHORT|FI_STATE|FI_FRAGBODY|FI_BAD)))
3001 return NULL;
3002
3003 is = NULL;
3004 if ((fin->fin_flx & FI_TCPUDP) ||
3005 (fin->fin_fi.fi_p == IPPROTO_ICMP)
3006 #ifdef USE_INET6
3007 || (fin->fin_fi.fi_p == IPPROTO_ICMPV6)
3008 #endif
3009 )
3010 tcp = fin->fin_dp;
3011 else
3012 tcp = NULL;
3013
3014 /*
3015 * Search the hash table for matching packet header info.
3016 */
3017 ifq = NULL;
3018 is = fr_stlookup(fin, tcp, &ifq);
3019 switch (fin->fin_p)
3020 {
3021 #ifdef USE_INET6
3022 case IPPROTO_ICMPV6 :
3023 if (is != NULL)
3024 break;
3025 if (fin->fin_v == 6) {
3026 is = fr_checkicmp6matchingstate(fin);
3027 if (is != NULL)
3028 goto matched;
3029 }
3030 break;
3031 #endif
3032 case IPPROTO_ICMP :
3033 if (is != NULL)
3034 break;
3035 /*
3036 * No matching icmp state entry. Perhaps this is a
3037 * response to another state entry.
3038 */
3039 is = fr_checkicmpmatchingstate(fin);
3040 if (is != NULL)
3041 goto matched;
3042 break;
3043 case IPPROTO_TCP :
3044 if (is == NULL)
3045 break;
3046
3047 if (is->is_pass & FR_NEWISN) {
3048 if (fin->fin_out == 0)
3049 fr_fixinisn(fin, is);
3050 else if (fin->fin_out == 1)
3051 fr_fixoutisn(fin, is);
3052 }
3053 break;
3054 default :
3055 if (fin->fin_rev)
3056 ifq = &ifs->ifs_ips_udpacktq;
3057 else
3058 ifq = &ifs->ifs_ips_udptq;
3059 break;
3060 }
3061 if (is == NULL) {
3062 ATOMIC_INCL(ifs->ifs_ips_stats.iss_miss);
3063 return NULL;
3064 }
3065
3066 matched:
3067 fr = is->is_rule;
3068 if (fr != NULL) {
3069 if ((fin->fin_out == 0) && (fr->fr_nattag.ipt_num[0] != 0)) {
3070 if (fin->fin_nattag == NULL) {
3071 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3072 return NULL;
3073 }
3074 if (fr_matchtag(&fr->fr_nattag, fin->fin_nattag) != 0) {
3075 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3076 return NULL;
3077 }
3078 }
3079 (void) strncpy(fin->fin_group, fr->fr_group, FR_GROUPLEN);
3080 fin->fin_icode = fr->fr_icode;
3081 }
3082
3083 fin->fin_rule = is->is_rulen;
3084 pass = is->is_pass;
3085 fr_updatestate(fin, is, ifq);
3086
3087 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3088 fin->fin_flx |= FI_STATE;
3089 if ((pass & FR_LOGFIRST) != 0)
3090 pass &= ~(FR_LOGFIRST|FR_LOG);
3091 *passp = pass;
3092 return fr;
3093 }
3094
3095
3096 /* ------------------------------------------------------------------------ */
3097 /* Function: fr_fixoutisn */
3098 /* Returns: Nil */
3099 /* Parameters: fin(I) - pointer to packet information */
3100 /* is(I) - pointer to master state structure */
3101 /* */
3102 /* Called only for outbound packets, adjusts the sequence number and the */
3103 /* TCP checksum to match that change. */
3104 /* ------------------------------------------------------------------------ */
3105 static void fr_fixoutisn(fin, is)
3106 fr_info_t *fin;
3107 ipstate_t *is;
3108 {
3109 tcphdr_t *tcp;
3110 int rev;
3111 u_32_t seq;
3112
3113 tcp = fin->fin_dp;
3114 rev = fin->fin_rev;
3115 if ((is->is_flags & IS_ISNSYN) != 0) {
3116 if (rev == 0) {
3117 seq = ntohl(tcp->th_seq);
3118 seq += is->is_isninc[0];
3119 tcp->th_seq = htonl(seq);
3120 fix_outcksum(&tcp->th_sum, is->is_sumd[0]);
3121 }
3122 }
3123 if ((is->is_flags & IS_ISNACK) != 0) {
3124 if (rev == 1) {
3125 seq = ntohl(tcp->th_seq);
3126 seq += is->is_isninc[1];
3127 tcp->th_seq = htonl(seq);
3128 fix_outcksum(&tcp->th_sum, is->is_sumd[1]);
3129 }
3130 }
3131 }
3132
3133
3134 /* ------------------------------------------------------------------------ */
3135 /* Function: fr_fixinisn */
3136 /* Returns: Nil */
3137 /* Parameters: fin(I) - pointer to packet information */
3138 /* is(I) - pointer to master state structure */
3139 /* */
3140 /* Called only for inbound packets, adjusts the acknowledge number and the */
3141 /* TCP checksum to match that change. */
3142 /* ------------------------------------------------------------------------ */
3143 static void fr_fixinisn(fin, is)
3144 fr_info_t *fin;
3145 ipstate_t *is;
3146 {
3147 tcphdr_t *tcp;
3148 int rev;
3149 u_32_t ack;
3150
3151 tcp = fin->fin_dp;
3152 rev = fin->fin_rev;
3153 if ((is->is_flags & IS_ISNSYN) != 0) {
3154 if (rev == 1) {
3155 ack = ntohl(tcp->th_ack);
3156 ack -= is->is_isninc[0];
3157 tcp->th_ack = htonl(ack);
3158 fix_incksum(&tcp->th_sum, is->is_sumd[0]);
3159 }
3160 }
3161 if ((is->is_flags & IS_ISNACK) != 0) {
3162 if (rev == 0) {
3163 ack = ntohl(tcp->th_ack);
3164 ack -= is->is_isninc[1];
3165 tcp->th_ack = htonl(ack);
3166 fix_incksum(&tcp->th_sum, is->is_sumd[1]);
3167 }
3168 }
3169 }
3170
3171
3172 /* ------------------------------------------------------------------------ */
3173 /* Function: fr_statesync */
3174 /* Returns: Nil */
3175 /* Parameters: action(I) - type of synchronisation to do */
3176 /* v(I) - IP version being sync'd (v4 or v6) */
3177 /* ifp(I) - interface identifier associated with action */
3178 /* name(I) - name associated with ifp parameter */
3179 /* */
3180 /* Walk through all state entries and if an interface pointer match is */
3181 /* found then look it up again, based on its name in case the pointer has */
3182 /* changed since last time. */
3183 /* */
3184 /* If ifp is passed in as being non-null then we are only doing updates for */
3185 /* existing, matching, uses of it. */
3186 /* ------------------------------------------------------------------------ */
3187 void fr_statesync(action, v, ifp, name, ifs)
3188 int action, v;
3189 void *ifp;
3190 char *name;
3191 ipf_stack_t *ifs;
3192 {
3193 ipstate_t *is;
3194 int i;
3195
3196 if (ifs->ifs_fr_running <= 0)
3197 return;
3198
3199 WRITE_ENTER(&ifs->ifs_ipf_state);
3200
3201 if (ifs->ifs_fr_running <= 0) {
3202 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3203 return;
3204 }
3205
3206 switch (action)
3207 {
3208 case IPFSYNC_RESYNC :
3209 for (is = ifs->ifs_ips_list; is; is = is->is_next) {
3210 if (v != 0 && is->is_v != v)
3211 continue;
3212 /*
3213 * Look up all the interface names in the state entry.
3214 */
3215 for (i = 0; i < 4; i++) {
3216 is->is_ifp[i] = fr_resolvenic(is->is_ifname[i],
3217 is->is_v, ifs);
3218 }
3219 }
3220 break;
3221 case IPFSYNC_NEWIFP :
3222 for (is = ifs->ifs_ips_list; is; is = is->is_next) {
3223 if (v != 0 && is->is_v != v)
3224 continue;
3225 /*
3226 * Look up all the interface names in the state entry.
3227 */
3228 for (i = 0; i < 4; i++) {
3229 if (!strncmp(is->is_ifname[i], name,
3230 sizeof(is->is_ifname[i])))
3231 is->is_ifp[i] = ifp;
3232 }
3233 }
3234 break;
3235 case IPFSYNC_OLDIFP :
3236 for (is = ifs->ifs_ips_list; is; is = is->is_next) {
3237 if (v != 0 && is->is_v != v)
3238 continue;
3239 /*
3240 * Look up all the interface names in the state entry.
3241 */
3242 for (i = 0; i < 4; i++) {
3243 if (is->is_ifp[i] == ifp)
3244 is->is_ifp[i] = (void *)-1;
3245 }
3246 }
3247 break;
3248 }
3249 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3250 }
3251
3252
3253 #if SOLARIS2 >= 10
3254 /* ------------------------------------------------------------------------ */
3255 /* Function: fr_stateifindexsync */
3256 /* Returns: void */
3257 /* Parameters: ifp - current network interface descriptor (ifindex) */
3258 /* newifp - new interface descriptor (new ifindex) */
3259 /* ifs - pointer to IPF stack */
3260 /* */
3261 /* Write Locks: assumes ipf_mutex is locked */
3262 /* */
3263 /* Updates all interface indeces matching to ifp with new interface index */
3264 /* value. */
3265 /* ------------------------------------------------------------------------ */
3266 void fr_stateifindexsync(ifp, newifp, ifs)
3267 void *ifp;
3268 void *newifp;
3269 ipf_stack_t *ifs;
3270 {
3271 ipstate_t *is;
3272 int i;
3273
3274 WRITE_ENTER(&ifs->ifs_ipf_state);
3275
3276 for (is = ifs->ifs_ips_list; is != NULL; is = is->is_next) {
3277
3278 for (i = 0; i < 4; i++) {
3279 if (is->is_ifp[i] == ifp)
3280 is->is_ifp[i] = newifp;
3281 }
3282 }
3283
3284 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3285 }
3286 #endif
3287
3288 /* ------------------------------------------------------------------------ */
3289 /* Function: fr_delstate */
3290 /* Returns: int - 0 = entry deleted, else ref count on entry */
3291 /* Parameters: is(I) - pointer to state structure to delete */
3292 /* why(I) - if not 0, log reason why it was deleted */
3293 /* ifs - ipf stack instance */
3294 /* Write Locks: ipf_state/ipf_global */
3295 /* */
3296 /* Deletes a state entry from the enumerated list as well as the hash table */
3297 /* and timeout queue lists. Make adjustments to hash table statistics and */
3298 /* global counters as required. */
3299 /* ------------------------------------------------------------------------ */
3300 int fr_delstate(is, why, ifs)
3301 ipstate_t *is;
3302 int why;
3303 ipf_stack_t *ifs;
3304 {
3305 int removed = 0;
3306
3307 ASSERT(rw_write_held(&ifs->ifs_ipf_global.ipf_lk) == 0 ||
3308 rw_write_held(&ifs->ifs_ipf_state.ipf_lk) == 0);
3309
3310 /*
3311 * Start by removing the entry from the hash table of state entries
3312 * so it will not be "used" again.
3313 *
3314 * It will remain in the "list" of state entries until all references
3315 * have been accounted for.
3316 */
3317 if (is->is_phnext != NULL) {
3318 removed = 1;
3319 *is->is_phnext = is->is_hnext;
3320 if (is->is_hnext != NULL)
3321 is->is_hnext->is_phnext = is->is_phnext;
3322 if (ifs->ifs_ips_table[is->is_hv] == NULL)
3323 ifs->ifs_ips_stats.iss_inuse--;
3324 ifs->ifs_ips_stats.iss_bucketlen[is->is_hv]--;
3325
3326 is->is_phnext = NULL;
3327 is->is_hnext = NULL;
3328 }
3329
3330 /*
3331 * Because ifs->ifs_ips_stats.iss_wild is a count of entries in the state
3332 * table that have wildcard flags set, only decerement it once
3333 * and do it here.
3334 */
3335 if (is->is_flags & (SI_WILDP|SI_WILDA)) {
3336 if (!(is->is_flags & SI_CLONED)) {
3337 ATOMIC_DECL(ifs->ifs_ips_stats.iss_wild);
3338 }
3339 is->is_flags &= ~(SI_WILDP|SI_WILDA);
3340 }
3341
3342 /*
3343 * Next, remove it from the timeout queue it is in.
3344 */
3345 fr_deletequeueentry(&is->is_sti);
3346
3347 is->is_me = NULL;
3348
3349 /*
3350 * If it is still in use by something else, do not go any further,
3351 * but note that at this point it is now an orphan.
3352 */
3353 MUTEX_ENTER(&is->is_lock);
3354 if (is->is_ref > 1) {
3355 is->is_ref--;
3356 MUTEX_EXIT(&is->is_lock);
3357 if (removed)
3358 ifs->ifs_ips_stats.iss_orphans++;
3359 return (is->is_ref);
3360 }
3361 MUTEX_EXIT(&is->is_lock);
3362
3363 is->is_ref = 0;
3364
3365 /*
3366 * If entry has already been removed from table,
3367 * it means we're simply cleaning up an orphan.
3368 */
3369 if (!removed)
3370 ifs->ifs_ips_stats.iss_orphans--;
3371
3372 if (is->is_tqehead[0] != NULL)
3373 (void) fr_deletetimeoutqueue(is->is_tqehead[0]);
3374
3375 if (is->is_tqehead[1] != NULL)
3376 (void) fr_deletetimeoutqueue(is->is_tqehead[1]);
3377
3378 #ifdef IPFILTER_SYNC
3379 if (is->is_sync)
3380 ipfsync_del(is->is_sync);
3381 #endif
3382 #ifdef IPFILTER_SCAN
3383 (void) ipsc_detachis(is);
3384 #endif
3385
3386 /*
3387 * Now remove it from master list of state table entries.
3388 */
3389 if (is->is_pnext != NULL) {
3390 *is->is_pnext = is->is_next;
3391 if (is->is_next != NULL) {
3392 is->is_next->is_pnext = is->is_pnext;
3393 is->is_next = NULL;
3394 }
3395 is->is_pnext = NULL;
3396 }
3397
3398 if (ifs->ifs_ipstate_logging != 0 && why != 0)
3399 ipstate_log(is, why, ifs);
3400
3401 if (is->is_rule != NULL) {
3402 is->is_rule->fr_statecnt--;
3403 (void)fr_derefrule(&is->is_rule, ifs);
3404 }
3405
3406 MUTEX_DESTROY(&is->is_lock);
3407 KFREE(is);
3408 ifs->ifs_ips_num--;
3409
3410 return (0);
3411 }
3412
3413
3414 /* ------------------------------------------------------------------------ */
3415 /* Function: fr_timeoutstate */
3416 /* Returns: Nil */
3417 /* Parameters: ifs - ipf stack instance */
3418 /* */
3419 /* Slowly expire held state for thingslike UDP and ICMP. The algorithm */
3420 /* used here is to keep the queue sorted with the oldest things at the top */
3421 /* and the youngest at the bottom. So if the top one doesn't need to be */
3422 /* expired then neither will any under it. */
3423 /* ------------------------------------------------------------------------ */
3424 void fr_timeoutstate(ifs)
3425 ipf_stack_t *ifs;
3426 {
3427 ipftq_t *ifq, *ifqnext;
3428 ipftqent_t *tqe, *tqn;
3429 ipstate_t *is;
3430 SPL_INT(s);
3431
3432 SPL_NET(s);
3433 WRITE_ENTER(&ifs->ifs_ipf_state);
3434 for (ifq = ifs->ifs_ips_tqtqb; ifq != NULL; ifq = ifq->ifq_next)
3435 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) {
3436 if (tqe->tqe_die > ifs->ifs_fr_ticks)
3437 break;
3438 tqn = tqe->tqe_next;
3439 is = tqe->tqe_parent;
3440 (void) fr_delstate(is, ISL_EXPIRE, ifs);
3441 }
3442
3443 for (ifq = ifs->ifs_ips_utqe; ifq != NULL; ifq = ifq->ifq_next) {
3444 for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) {
3445 if (tqe->tqe_die > ifs->ifs_fr_ticks)
3446 break;
3447 tqn = tqe->tqe_next;
3448 is = tqe->tqe_parent;
3449 (void) fr_delstate(is, ISL_EXPIRE, ifs);
3450 }
3451 }
3452
3453 for (ifq = ifs->ifs_ips_utqe; ifq != NULL; ifq = ifqnext) {
3454 ifqnext = ifq->ifq_next;
3455
3456 if (((ifq->ifq_flags & IFQF_DELETE) != 0) &&
3457 (ifq->ifq_ref == 0)) {
3458 fr_freetimeoutqueue(ifq, ifs);
3459 }
3460 }
3461
3462 if (ifs->ifs_fr_state_doflush) {
3463 (void) fr_state_flush(FLUSH_TABLE_EXTRA, 0, ifs);
3464 ifs->ifs_fr_state_doflush = 0;
3465 }
3466 RWLOCK_EXIT(&ifs->ifs_ipf_state);
3467 SPL_X(s);
3468 }
3469
3470
3471 /* ---------------------------------------------------------------------- */
3472 /* Function: fr_state_flush */
3473 /* Returns: int - 0 == success, -1 == failure */
3474 /* Parameters: flush_option - how to flush the active State table */
3475 /* proto - IP version to flush (4, 6, or both) */
3476 /* ifs - ipf stack instance */
3477 /* Write Locks: ipf_state */
3478 /* */
3479 /* Flush state tables. Three possible flush options currently defined: */
3480 /* */
3481 /* FLUSH_TABLE_ALL : Flush all state table entries */
3482 /* */
3483 /* FLUSH_TABLE_CLOSING : Flush entries with TCP connections which */
3484 /* have started to close on both ends using */
3485 /* ipf_flushclosing(). */
3486 /* */
3487 /* FLUSH_TABLE_EXTRA : First, flush entries which are "almost" closed. */
3488 /* Then, if needed, flush entries with TCP */
3489 /* connections which have been idle for a long */
3490 /* time with ipf_extraflush(). */
3491 /* ---------------------------------------------------------------------- */
3492 static int fr_state_flush(flush_option, proto, ifs)
3493 int flush_option, proto;
3494 ipf_stack_t *ifs;
3495 {
3496 ipstate_t *is, *isn;
3497 int removed;
3498 SPL_INT(s);
3499
3500 removed = 0;
3501
3502 SPL_NET(s);
3503 switch (flush_option)
3504 {
3505 case FLUSH_TABLE_ALL:
3506 isn = ifs->ifs_ips_list;
3507 while ((is = isn) != NULL) {
3508 isn = is->is_next;
3509 if ((proto != 0) && (is->is_v != proto))
3510 continue;
3511 if (fr_delstate(is, ISL_FLUSH, ifs) == 0)
3512 removed++;
3513 }
3514 break;
3515
3516 case FLUSH_TABLE_CLOSING:
3517 removed = ipf_flushclosing(STATE_FLUSH,
3518 IPF_TCPS_CLOSE_WAIT,
3519 ifs->ifs_ips_tqtqb,
3520 ifs->ifs_ips_utqe,
3521 ifs);
3522 break;
3523
3524 case FLUSH_TABLE_EXTRA:
3525 removed = ipf_flushclosing(STATE_FLUSH,
3526 IPF_TCPS_FIN_WAIT_2,
3527 ifs->ifs_ips_tqtqb,
3528 ifs->ifs_ips_utqe,
3529 ifs);
3530
3531 /*
3532 * Be sure we haven't done this in the last 10 seconds.
3533 */
3534 if (ifs->ifs_fr_ticks - ifs->ifs_ips_last_force_flush <
3535 IPF_TTLVAL(10))
3536 break;
3537 ifs->ifs_ips_last_force_flush = ifs->ifs_fr_ticks;
3538 removed += ipf_extraflush(STATE_FLUSH,
3539 &ifs->ifs_ips_tqtqb[IPF_TCPS_ESTABLISHED],
3540 ifs->ifs_ips_utqe,
3541 ifs);
3542 break;
3543
3544 default: /* Flush Nothing */
3545 break;
3546 }
3547
3548 SPL_X(s);
3549 return (removed);
3550 }
3551
3552
3553 /* ------------------------------------------------------------------------ */
3554 /* Function: fr_tcp_age */
3555 /* Returns: int - 1 == state transition made, 0 == no change (rejected) */
3556 /* Parameters: tq(I) - pointer to timeout queue information */
3557 /* fin(I) - pointer to packet information */
3558 /* tqtab(I) - TCP timeout queue table this is in */
3559 /* flags(I) - flags from state/NAT entry */
3560 /* */
3561 /* Rewritten by Arjan de Vet <Arjan.deVet@adv.iae.nl>, 2000-07-29: */
3562 /* */
3563 /* - (try to) base state transitions on real evidence only, */
3564 /* i.e. packets that are sent and have been received by ipfilter; */
3565 /* diagram 18.12 of TCP/IP volume 1 by W. Richard Stevens was used. */
3566 /* */
3567 /* - deal with half-closed connections correctly; */
3568 /* */
3569 /* - store the state of the source in state[0] such that ipfstat */
3570 /* displays the state as source/dest instead of dest/source; the calls */
3571 /* to fr_tcp_age have been changed accordingly. */
3572 /* */
3573 /* Internal Parameters: */
3574 /* */
3575 /* state[0] = state of source (host that initiated connection) */
3576 /* state[1] = state of dest (host that accepted the connection) */
3577 /* */
3578 /* dir == 0 : a packet from source to dest */
3579 /* dir == 1 : a packet from dest to source */
3580 /* */
3581 /* Locking: it is assumed that the parent of the tqe structure is locked. */
3582 /* ------------------------------------------------------------------------ */
3583 int fr_tcp_age(tqe, fin, tqtab, flags)
3584 ipftqent_t *tqe;
3585 fr_info_t *fin;
3586 ipftq_t *tqtab;
3587 int flags;
3588 {
3589 int dlen, ostate, nstate, rval, dir;
3590 u_char tcpflags;
3591 tcphdr_t *tcp;
3592 ipf_stack_t *ifs = fin->fin_ifs;
3593
3594 tcp = fin->fin_dp;
3595
3596 rval = 0;
3597 dir = fin->fin_rev;
3598 tcpflags = tcp->th_flags;
3599 dlen = fin->fin_dlen - (TCP_OFF(tcp) << 2);
3600
3601 ostate = tqe->tqe_state[1 - dir];
3602 nstate = tqe->tqe_state[dir];
3603
3604 DTRACE_PROBE4(
3605 indata,
3606 fr_info_t *, fin,
3607 int, ostate,
3608 int, nstate,
3609 u_char, tcpflags
3610 );
3611
3612 if (tcpflags & TH_RST) {
3613 if (!(tcpflags & TH_PUSH) && !dlen)
3614 nstate = IPF_TCPS_CLOSED;
3615 else
3616 nstate = IPF_TCPS_CLOSE_WAIT;
3617
3618 /*
3619 * Once RST is received, we must advance peer's state to
3620 * CLOSE_WAIT.
3621 */
3622 if (ostate <= IPF_TCPS_ESTABLISHED) {
3623 tqe->tqe_state[1 - dir] = IPF_TCPS_CLOSE_WAIT;
3624 }
3625 rval = 1;
3626 } else {
3627
3628 switch (nstate)
3629 {
3630 case IPF_TCPS_LISTEN: /* 0 */
3631 if ((tcpflags & TH_OPENING) == TH_OPENING) {
3632 /*
3633 * 'dir' received an S and sends SA in
3634 * response, CLOSED -> SYN_RECEIVED
3635 */
3636 nstate = IPF_TCPS_SYN_RECEIVED;
3637 rval = 1;
3638 } else if ((tcpflags & TH_OPENING) == TH_SYN) {
3639 /* 'dir' sent S, CLOSED -> SYN_SENT */
3640 nstate = IPF_TCPS_SYN_SENT;
3641 rval = 1;
3642 }
3643 /*
3644 * the next piece of code makes it possible to get
3645 * already established connections into the state table
3646 * after a restart or reload of the filter rules; this
3647 * does not work when a strict 'flags S keep state' is
3648 * used for tcp connections of course
3649 */
3650 if (((flags & IS_TCPFSM) == 0) &&
3651 ((tcpflags & TH_ACKMASK) == TH_ACK)) {
3652 /*
3653 * we saw an A, guess 'dir' is in ESTABLISHED
3654 * mode
3655 */
3656 switch (ostate)
3657 {
3658 case IPF_TCPS_LISTEN :
3659 case IPF_TCPS_SYN_RECEIVED :
3660 nstate = IPF_TCPS_HALF_ESTAB;
3661 rval = 1;
3662 break;
3663 case IPF_TCPS_HALF_ESTAB :
3664 case IPF_TCPS_ESTABLISHED :
3665 nstate = IPF_TCPS_ESTABLISHED;
3666 rval = 1;
3667 break;
3668 default :
3669 break;
3670 }
3671 }
3672 /*
3673 * TODO: besides regular ACK packets we can have other
3674 * packets as well; it is yet to be determined how we
3675 * should initialize the states in those cases
3676 */
3677 break;
3678
3679 case IPF_TCPS_SYN_SENT: /* 1 */
3680 if ((tcpflags & ~(TH_ECN|TH_CWR)) == TH_SYN) {
3681 /*
3682 * A retransmitted SYN packet. We do not reset
3683 * the timeout here to fr_tcptimeout because a
3684 * connection connect timeout does not renew
3685 * after every packet that is sent. We need to
3686 * set rval so as to indicate the packet has
3687 * passed the check for its flags being valid
3688 * in the TCP FSM. Setting rval to 2 has the
3689 * result of not resetting the timeout.
3690 */
3691 rval = 2;
3692 } else if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) ==
3693 TH_ACK) {
3694 /*
3695 * we see an A from 'dir' which is in SYN_SENT
3696 * state: 'dir' sent an A in response to an SA
3697 * which it received, SYN_SENT -> ESTABLISHED
3698 */
3699 nstate = IPF_TCPS_ESTABLISHED;
3700 rval = 1;
3701 } else if (tcpflags & TH_FIN) {
3702 /*
3703 * we see an F from 'dir' which is in SYN_SENT
3704 * state and wants to close its side of the
3705 * connection; SYN_SENT -> FIN_WAIT_1
3706 */
3707 nstate = IPF_TCPS_FIN_WAIT_1;
3708 rval = 1;
3709 } else if ((tcpflags & TH_OPENING) == TH_OPENING) {
3710 /*
3711 * we see an SA from 'dir' which is already in
3712 * SYN_SENT state, this means we have a
3713 * simultaneous open; SYN_SENT -> SYN_RECEIVED
3714 */
3715 nstate = IPF_TCPS_SYN_RECEIVED;
3716 rval = 1;
3717 }
3718 break;
3719
3720 case IPF_TCPS_SYN_RECEIVED: /* 2 */
3721 if ((tcpflags & (TH_SYN|TH_FIN|TH_ACK)) == TH_ACK) {
3722 /*
3723 * we see an A from 'dir' which was in
3724 * SYN_RECEIVED state so it must now be in
3725 * established state, SYN_RECEIVED ->
3726 * ESTABLISHED
3727 */
3728 nstate = IPF_TCPS_ESTABLISHED;
3729 rval = 1;
3730 } else if ((tcpflags & ~(TH_ECN|TH_CWR)) ==
3731 TH_OPENING) {
3732 /*
3733 * We see an SA from 'dir' which is already in
3734 * SYN_RECEIVED state.
3735 */
3736 rval = 2;
3737 } else if (tcpflags & TH_FIN) {
3738 /*
3739 * we see an F from 'dir' which is in
3740 * SYN_RECEIVED state and wants to close its
3741 * side of the connection; SYN_RECEIVED ->
3742 * FIN_WAIT_1
3743 */
3744 nstate = IPF_TCPS_FIN_WAIT_1;
3745 rval = 1;
3746 }
3747 break;
3748
3749 case IPF_TCPS_HALF_ESTAB: /* 3 */
3750 if (tcpflags & TH_FIN) {
3751 nstate = IPF_TCPS_FIN_WAIT_1;
3752 rval = 1;
3753 } else if ((tcpflags & TH_ACKMASK) == TH_ACK) {
3754 /*
3755 * If we've picked up a connection in mid
3756 * flight, we could be looking at a follow on
3757 * packet from the same direction as the one
3758 * that created this state. Recognise it but
3759 * do not advance the entire connection's
3760 * state.
3761 */
3762 switch (ostate)
3763 {
3764 case IPF_TCPS_LISTEN :
3765 case IPF_TCPS_SYN_SENT :
3766 case IPF_TCPS_SYN_RECEIVED :
3767 rval = 1;
3768 break;
3769 case IPF_TCPS_HALF_ESTAB :
3770 case IPF_TCPS_ESTABLISHED :
3771 nstate = IPF_TCPS_ESTABLISHED;
3772 rval = 1;
3773 break;
3774 default :
3775 break;
3776 }
3777 }
3778 break;
3779
3780 case IPF_TCPS_ESTABLISHED: /* 4 */
3781 rval = 1;
3782 if (tcpflags & TH_FIN) {
3783 /*
3784 * 'dir' closed its side of the connection;
3785 * this gives us a half-closed connection;
3786 * ESTABLISHED -> FIN_WAIT_1
3787 */
3788 if (ostate == IPF_TCPS_FIN_WAIT_1) {
3789 nstate = IPF_TCPS_CLOSING;
3790 } else {
3791 nstate = IPF_TCPS_FIN_WAIT_1;
3792 }
3793 } else if (tcpflags & TH_ACK) {
3794 /*
3795 * an ACK, should we exclude other flags here?
3796 */
3797 if (ostate == IPF_TCPS_FIN_WAIT_1) {
3798 /*
3799 * We know the other side did an active
3800 * close, so we are ACKing the recvd
3801 * FIN packet (does the window matching
3802 * code guarantee this?) and go into
3803 * CLOSE_WAIT state; this gives us a
3804 * half-closed connection
3805 */
3806 nstate = IPF_TCPS_CLOSE_WAIT;
3807 } else if (ostate < IPF_TCPS_CLOSE_WAIT) {
3808 /*
3809 * still a fully established
3810 * connection reset timeout
3811 */
3812 nstate = IPF_TCPS_ESTABLISHED;
3813 }
3814 }
3815 break;
3816
3817 case IPF_TCPS_CLOSE_WAIT: /* 5 */
3818 rval = 1;
3819 if (tcpflags & TH_FIN) {
3820 /*
3821 * application closed and 'dir' sent a FIN,
3822 * we're now going into LAST_ACK state
3823 */
3824 nstate = IPF_TCPS_LAST_ACK;
3825 } else {
3826 /*
3827 * we remain in CLOSE_WAIT because the other
3828 * side has closed already and we did not
3829 * close our side yet; reset timeout
3830 */
3831 nstate = IPF_TCPS_CLOSE_WAIT;
3832 }
3833 break;
3834
3835 case IPF_TCPS_FIN_WAIT_1: /* 6 */
3836 rval = 1;
3837 if ((tcpflags & TH_ACK) &&
3838 ostate > IPF_TCPS_CLOSE_WAIT) {
3839 /*
3840 * if the other side is not active anymore
3841 * it has sent us a FIN packet that we are
3842 * ack'ing now with an ACK; this means both
3843 * sides have now closed the connection and
3844 * we go into LAST_ACK
3845 */
3846 /*
3847 * XXX: how do we know we really are ACKing
3848 * the FIN packet here? does the window code
3849 * guarantee that?
3850 */
3851 nstate = IPF_TCPS_LAST_ACK;
3852 } else {
3853 /*
3854 * we closed our side of the connection
3855 * already but the other side is still active
3856 * (ESTABLISHED/CLOSE_WAIT); continue with
3857 * this half-closed connection
3858 */
3859 nstate = IPF_TCPS_FIN_WAIT_1;
3860 }
3861 break;
3862
3863 case IPF_TCPS_CLOSING: /* 7 */
3864 if ((tcpflags & (TH_FIN|TH_ACK)) == TH_ACK) {
3865 nstate = IPF_TCPS_TIME_WAIT;
3866 }
3867 rval = 1;
3868 break;
3869
3870 case IPF_TCPS_LAST_ACK: /* 8 */
3871 /*
3872 * We want to reset timer here to keep state in table.
3873 * If we would allow the state to time out here, while
3874 * there would still be packets being retransmitted, we
3875 * would cut off line between the two peers preventing
3876 * them to close connection properly.
3877 */
3878 rval = 1;
3879 break;
3880
3881 case IPF_TCPS_FIN_WAIT_2: /* 9 */
3882 /* NOT USED */
3883 break;
3884
3885 case IPF_TCPS_TIME_WAIT: /* 10 */
3886 /* we're in 2MSL timeout now */
3887 if (ostate == IPF_TCPS_LAST_ACK) {
3888 nstate = IPF_TCPS_CLOSED;
3889 rval = 1;
3890 } else {
3891 rval = 2;
3892 }
3893 break;
3894
3895 case IPF_TCPS_CLOSED: /* 11 */
3896 rval = 2;
3897 break;
3898
3899 default :
3900 #if defined(_KERNEL)
3901 ASSERT(nstate >= IPF_TCPS_LISTEN &&
3902 nstate <= IPF_TCPS_CLOSED);
3903 #else
3904 abort();
3905 #endif
3906 break;
3907 }
3908 }
3909
3910 /*
3911 * If rval == 2 then do not update the queue position, but treat the
3912 * packet as being ok.
3913 */
3914 if (rval == 2) {
3915 DTRACE_PROBE1(state_keeping_timer, int, nstate);
3916 rval = 1;
3917 }
3918 else if (rval == 1) {
3919 tqe->tqe_state[dir] = nstate;
3920 /*
3921 * The nstate can either advance to a new state, or remain
3922 * unchanged, resetting the timer by moving to the bottom of
3923 * the queue.
3924 */
3925 DTRACE_PROBE1(state_done, int, nstate);
3926
3927 if ((tqe->tqe_flags & TQE_RULEBASED) == 0)
3928 fr_movequeue(tqe, tqe->tqe_ifq, tqtab + nstate, ifs);
3929 }
3930
3931 return rval;
3932 }
3933
3934
3935 /* ------------------------------------------------------------------------ */
3936 /* Function: ipstate_log */
3937 /* Returns: Nil */
3938 /* Parameters: is(I) - pointer to state structure */
3939 /* type(I) - type of log entry to create */
3940 /* */
3941 /* Creates a state table log entry using the state structure and type info. */
3942 /* passed in. Log packet/byte counts, source/destination address and other */
3943 /* protocol specific information. */
3944 /* ------------------------------------------------------------------------ */
3945 void ipstate_log(is, type, ifs)
3946 struct ipstate *is;
3947 u_int type;
3948 ipf_stack_t *ifs;
3949 {
3950 #ifdef IPFILTER_LOG
3951 struct ipslog ipsl;
3952 size_t sizes[1];
3953 void *items[1];
3954 int types[1];
3955
3956 /*
3957 * Copy information out of the ipstate_t structure and into the
3958 * structure used for logging.
3959 */
3960 ipsl.isl_type = type;
3961 ipsl.isl_pkts[0] = is->is_pkts[0] + is->is_icmppkts[0];
3962 ipsl.isl_bytes[0] = is->is_bytes[0];
3963 ipsl.isl_pkts[1] = is->is_pkts[1] + is->is_icmppkts[1];
3964 ipsl.isl_bytes[1] = is->is_bytes[1];
3965 ipsl.isl_pkts[2] = is->is_pkts[2] + is->is_icmppkts[2];
3966 ipsl.isl_bytes[2] = is->is_bytes[2];
3967 ipsl.isl_pkts[3] = is->is_pkts[3] + is->is_icmppkts[3];
3968 ipsl.isl_bytes[3] = is->is_bytes[3];
3969 ipsl.isl_src = is->is_src;
3970 ipsl.isl_dst = is->is_dst;
3971 ipsl.isl_p = is->is_p;
3972 ipsl.isl_v = is->is_v;
3973 ipsl.isl_flags = is->is_flags;
3974 ipsl.isl_tag = is->is_tag;
3975 ipsl.isl_rulen = is->is_rulen;
3976 (void) strncpy(ipsl.isl_group, is->is_group, FR_GROUPLEN);
3977
3978 if (ipsl.isl_p == IPPROTO_TCP || ipsl.isl_p == IPPROTO_UDP) {
3979 ipsl.isl_sport = is->is_sport;
3980 ipsl.isl_dport = is->is_dport;
3981 if (ipsl.isl_p == IPPROTO_TCP) {
3982 ipsl.isl_state[0] = is->is_state[0];
3983 ipsl.isl_state[1] = is->is_state[1];
3984 }
3985 } else if (ipsl.isl_p == IPPROTO_ICMP) {
3986 ipsl.isl_itype = is->is_icmp.ici_type;
3987 } else if (ipsl.isl_p == IPPROTO_ICMPV6) {
3988 ipsl.isl_itype = is->is_icmp.ici_type;
3989 } else {
3990 ipsl.isl_ps.isl_filler[0] = 0;
3991 ipsl.isl_ps.isl_filler[1] = 0;
3992 }
3993
3994 items[0] = &ipsl;
3995 sizes[0] = sizeof(ipsl);
3996 types[0] = 0;
3997
3998 if (ipllog(IPL_LOGSTATE, NULL, items, sizes, types, 1, ifs)) {
3999 ATOMIC_INCL(ifs->ifs_ips_stats.iss_logged);
4000 } else {
4001 ATOMIC_INCL(ifs->ifs_ips_stats.iss_logfail);
4002 }
4003 #endif
4004 }
4005
4006
4007 #ifdef USE_INET6
4008 /* ------------------------------------------------------------------------ */
4009 /* Function: fr_checkicmp6matchingstate */
4010 /* Returns: ipstate_t* - NULL == no match found, */
4011 /* else pointer to matching state entry */
4012 /* Parameters: fin(I) - pointer to packet information */
4013 /* Locks: NULL == no locks, else Read Lock on ipf_state */
4014 /* */
4015 /* If we've got an ICMPv6 error message, using the information stored in */
4016 /* the ICMPv6 packet, look for a matching state table entry. */
4017 /* ------------------------------------------------------------------------ */
4018 static ipstate_t *fr_checkicmp6matchingstate(fin)
4019 fr_info_t *fin;
4020 {
4021 struct icmp6_hdr *ic6, *oic;
4022 int backward, i;
4023 ipstate_t *is, **isp;
4024 u_short sport, dport;
4025 i6addr_t dst, src;
4026 u_short savelen;
4027 icmpinfo_t *ic;
4028 fr_info_t ofin;
4029 tcphdr_t *tcp;
4030 ip6_t *oip6;
4031 u_char pr;
4032 u_int hv;
4033 ipf_stack_t *ifs = fin->fin_ifs;
4034
4035 /*
4036 * Does it at least have the return (basic) IP header ?
4037 * Is it an actual recognised ICMP error type?
4038 * Only a basic IP header (no options) should be with
4039 * an ICMP error header.
4040 */
4041 if ((fin->fin_v != 6) || (fin->fin_plen < ICMP6ERR_MINPKTLEN) ||
4042 !(fin->fin_flx & FI_ICMPERR))
4043 return NULL;
4044
4045 ic6 = fin->fin_dp;
4046
4047 oip6 = (ip6_t *)((char *)ic6 + ICMPERR_ICMPHLEN);
4048 if (fin->fin_plen < sizeof(*oip6))
4049 return NULL;
4050
4051 bcopy((char *)fin, (char *)&ofin, sizeof(*fin));
4052 ofin.fin_v = 6;
4053 ofin.fin_ifp = fin->fin_ifp;
4054 ofin.fin_out = !fin->fin_out;
4055 ofin.fin_m = NULL; /* if dereferenced, panic XXX */
4056 ofin.fin_mp = NULL; /* if dereferenced, panic XXX */
4057
4058 /*
4059 * We make a fin entry to be able to feed it to
4060 * matchsrcdst. Note that not all fields are necessary
4061 * but this is the cleanest way. Note further we fill
4062 * in fin_mp such that if someone uses it we'll get
4063 * a kernel panic. fr_matchsrcdst does not use this.
4064 *
4065 * watch out here, as ip is in host order and oip6 in network
4066 * order. Any change we make must be undone afterwards.
4067 */
4068 savelen = oip6->ip6_plen;
4069 oip6->ip6_plen = fin->fin_dlen - ICMPERR_ICMPHLEN;
4070 ofin.fin_flx = FI_NOCKSUM;
4071 ofin.fin_ip = (ip_t *)oip6;
4072 ofin.fin_plen = oip6->ip6_plen;
4073 (void) fr_makefrip(sizeof(*oip6), (ip_t *)oip6, &ofin);
4074 ofin.fin_flx &= ~(FI_BAD|FI_SHORT);
4075 oip6->ip6_plen = savelen;
4076
4077 if (oip6->ip6_nxt == IPPROTO_ICMPV6) {
4078 oic = (struct icmp6_hdr *)(oip6 + 1);
4079 /*
4080 * an ICMP error can only be generated as a result of an
4081 * ICMP query, not as the response on an ICMP error
4082 *
4083 * XXX theoretically ICMP_ECHOREP and the other reply's are
4084 * ICMP query's as well, but adding them here seems strange XXX
4085 */
4086 if (!(oic->icmp6_type & ICMP6_INFOMSG_MASK))
4087 return NULL;
4088
4089 /*
4090 * perform a lookup of the ICMP packet in the state table
4091 */
4092 hv = (pr = oip6->ip6_nxt);
4093 src.in6 = oip6->ip6_src;
4094 hv += src.in4.s_addr;
4095 dst.in6 = oip6->ip6_dst;
4096 hv += dst.in4.s_addr;
4097 hv += oic->icmp6_id;
4098 hv += oic->icmp6_seq;
4099 hv = DOUBLE_HASH(hv, ifs);
4100
4101 READ_ENTER(&ifs->ifs_ipf_state);
4102 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) {
4103 ic = &is->is_icmp;
4104 isp = &is->is_hnext;
4105 if ((is->is_p == pr) &&
4106 !(is->is_pass & FR_NOICMPERR) &&
4107 (oic->icmp6_id == ic->ici_id) &&
4108 (oic->icmp6_seq == ic->ici_seq) &&
4109 (is = fr_matchsrcdst(&ofin, is, &src,
4110 &dst, NULL, FI_ICMPCMP))) {
4111 /*
4112 * in the state table ICMP query's are stored
4113 * with the type of the corresponding ICMP
4114 * response. Correct here
4115 */
4116 if (((ic->ici_type == ICMP6_ECHO_REPLY) &&
4117 (oic->icmp6_type == ICMP6_ECHO_REQUEST)) ||
4118 (ic->ici_type - 1 == oic->icmp6_type )) {
4119 ifs->ifs_ips_stats.iss_hits++;
4120 backward = IP6_NEQ(&is->is_dst, &src);
4121 fin->fin_rev = !backward;
4122 i = (backward << 1) + fin->fin_out;
4123 is->is_icmppkts[i]++;
4124 return is;
4125 }
4126 }
4127 }
4128 RWLOCK_EXIT(&ifs->ifs_ipf_state);
4129 return NULL;
4130 }
4131
4132 hv = (pr = oip6->ip6_nxt);
4133 src.in6 = oip6->ip6_src;
4134 hv += src.i6[0];
4135 hv += src.i6[1];
4136 hv += src.i6[2];
4137 hv += src.i6[3];
4138 dst.in6 = oip6->ip6_dst;
4139 hv += dst.i6[0];
4140 hv += dst.i6[1];
4141 hv += dst.i6[2];
4142 hv += dst.i6[3];
4143
4144 if ((oip6->ip6_nxt == IPPROTO_TCP) || (oip6->ip6_nxt == IPPROTO_UDP)) {
4145 tcp = (tcphdr_t *)(oip6 + 1);
4146 dport = tcp->th_dport;
4147 sport = tcp->th_sport;
4148 hv += dport;
4149 hv += sport;
4150 } else
4151 tcp = NULL;
4152 hv = DOUBLE_HASH(hv, ifs);
4153
4154 READ_ENTER(&ifs->ifs_ipf_state);
4155 for (isp = &ifs->ifs_ips_table[hv]; ((is = *isp) != NULL); ) {
4156 isp = &is->is_hnext;
4157 /*
4158 * Only allow this icmp though if the
4159 * encapsulated packet was allowed through the
4160 * other way around. Note that the minimal amount
4161 * of info present does not allow for checking against
4162 * tcp internals such as seq and ack numbers.
4163 */
4164 if ((is->is_p != pr) || (is->is_v != 6) ||
4165 (is->is_pass & FR_NOICMPERR))
4166 continue;
4167 is = fr_matchsrcdst(&ofin, is, &src, &dst, tcp, FI_ICMPCMP);
4168 if (is != NULL) {
4169 ifs->ifs_ips_stats.iss_hits++;
4170 backward = IP6_NEQ(&is->is_dst, &src);
4171 fin->fin_rev = !backward;
4172 i = (backward << 1) + fin->fin_out;
4173 is->is_icmppkts[i]++;
4174 /*
4175 * we deliberately do not touch the timeouts
4176 * for the accompanying state table entry.
4177 * It remains to be seen if that is correct. XXX
4178 */
4179 return is;
4180 }
4181 }
4182 RWLOCK_EXIT(&ifs->ifs_ipf_state);
4183 return NULL;
4184 }
4185 #endif
4186
4187
4188 /* ------------------------------------------------------------------------ */
4189 /* Function: fr_sttab_init */
4190 /* Returns: Nil */
4191 /* Parameters: tqp(I) - pointer to an array of timeout queues for TCP */
4192 /* */
4193 /* Initialise the array of timeout queues for TCP. */
4194 /* ------------------------------------------------------------------------ */
4195 void fr_sttab_init(tqp, ifs)
4196 ipftq_t *tqp;
4197 ipf_stack_t *ifs;
4198 {
4199 int i;
4200
4201 for (i = IPF_TCP_NSTATES - 1; i >= 0; i--) {
4202 tqp[i].ifq_ttl = 0;
4203 tqp[i].ifq_ref = 1;
4204 tqp[i].ifq_head = NULL;
4205 tqp[i].ifq_tail = &tqp[i].ifq_head;
4206 tqp[i].ifq_next = tqp + i + 1;
4207 MUTEX_INIT(&tqp[i].ifq_lock, "ipftq tcp tab");
4208 }
4209 tqp[IPF_TCP_NSTATES - 1].ifq_next = NULL;
4210 tqp[IPF_TCPS_CLOSED].ifq_ttl = ifs->ifs_fr_tcpclosed;
4211 tqp[IPF_TCPS_LISTEN].ifq_ttl = ifs->ifs_fr_tcptimeout;
4212 tqp[IPF_TCPS_SYN_SENT].ifq_ttl = ifs->ifs_fr_tcptimeout;
4213 tqp[IPF_TCPS_SYN_RECEIVED].ifq_ttl = ifs->ifs_fr_tcptimeout;
4214 tqp[IPF_TCPS_ESTABLISHED].ifq_ttl = ifs->ifs_fr_tcpidletimeout;
4215 tqp[IPF_TCPS_CLOSE_WAIT].ifq_ttl = ifs->ifs_fr_tcphalfclosed;
4216 tqp[IPF_TCPS_FIN_WAIT_1].ifq_ttl = ifs->ifs_fr_tcphalfclosed;
4217 tqp[IPF_TCPS_CLOSING].ifq_ttl = ifs->ifs_fr_tcptimeout;
4218 tqp[IPF_TCPS_LAST_ACK].ifq_ttl = ifs->ifs_fr_tcplastack;
4219 tqp[IPF_TCPS_FIN_WAIT_2].ifq_ttl = ifs->ifs_fr_tcpclosewait;
4220 tqp[IPF_TCPS_TIME_WAIT].ifq_ttl = ifs->ifs_fr_tcptimeout;
4221 tqp[IPF_TCPS_HALF_ESTAB].ifq_ttl = ifs->ifs_fr_tcptimeout;
4222 }
4223
4224
4225 /* ------------------------------------------------------------------------ */
4226 /* Function: fr_sttab_destroy */
4227 /* Returns: Nil */
4228 /* Parameters: tqp(I) - pointer to an array of timeout queues for TCP */
4229 /* */
4230 /* Do whatever is necessary to "destroy" each of the entries in the array */
4231 /* of timeout queues for TCP. */
4232 /* ------------------------------------------------------------------------ */
4233 void fr_sttab_destroy(tqp)
4234 ipftq_t *tqp;
4235 {
4236 int i;
4237
4238 for (i = IPF_TCP_NSTATES - 1; i >= 0; i--)
4239 MUTEX_DESTROY(&tqp[i].ifq_lock);
4240 }
4241
4242
4243 /* ------------------------------------------------------------------------ */
4244 /* Function: fr_statederef */
4245 /* Returns: Nil */
4246 /* Parameters: isp(I) - pointer to pointer to state table entry */
4247 /* ifs - ipf stack instance */
4248 /* */
4249 /* Decrement the reference counter for this state table entry and free it */
4250 /* if there are no more things using it. */
4251 /* */
4252 /* Internal parameters: */
4253 /* state[0] = state of source (host that initiated connection) */
4254 /* state[1] = state of dest (host that accepted the connection) */
4255 /* ------------------------------------------------------------------------ */
4256 void fr_statederef(isp, ifs)
4257 ipstate_t **isp;
4258 ipf_stack_t *ifs;
4259 {
4260 ipstate_t *is;
4261
4262 is = *isp;
4263 *isp = NULL;
4264
4265 MUTEX_ENTER(&is->is_lock);
4266 if (is->is_ref > 1) {
4267 is->is_ref--;
4268 MUTEX_EXIT(&is->is_lock);
4269 #ifndef _KERNEL
4270 if ((is->is_sti.tqe_state[0] > IPF_TCPS_ESTABLISHED) ||
4271 (is->is_sti.tqe_state[1] > IPF_TCPS_ESTABLISHED)) {
4272 (void) fr_delstate(is, ISL_ORPHAN, ifs);
4273 }
4274 #endif
4275 return;
4276 }
4277 MUTEX_EXIT(&is->is_lock);
4278
4279 WRITE_ENTER(&ifs->ifs_ipf_state);
4280 (void) fr_delstate(is, ISL_EXPIRE, ifs);
4281 RWLOCK_EXIT(&ifs->ifs_ipf_state);
4282 }
4283
4284
4285 /* ------------------------------------------------------------------------ */
4286 /* Function: fr_setstatequeue */
4287 /* Returns: Nil */
4288 /* Parameters: is(I) - pointer to state structure */
4289 /* rev(I) - forward(0) or reverse(1) direction */
4290 /* Locks: ipf_state (read or write) */
4291 /* */
4292 /* Put the state entry on its default queue entry, using rev as a helped in */
4293 /* determining which queue it should be placed on. */
4294 /* ------------------------------------------------------------------------ */
4295 void fr_setstatequeue(is, rev, ifs)
4296 ipstate_t *is;
4297 int rev;
4298 ipf_stack_t *ifs;
4299 {
4300 ipftq_t *oifq, *nifq;
4301
4302
4303 if ((is->is_sti.tqe_flags & TQE_RULEBASED) != 0)
4304 nifq = is->is_tqehead[rev];
4305 else
4306 nifq = NULL;
4307
4308 if (nifq == NULL) {
4309 switch (is->is_p)
4310 {
4311 #ifdef USE_INET6
4312 case IPPROTO_ICMPV6 :
4313 if (rev == 1)
4314 nifq = &ifs->ifs_ips_icmpacktq;
4315 else
4316 nifq = &ifs->ifs_ips_icmptq;
4317 break;
4318 #endif
4319 case IPPROTO_ICMP :
4320 if (rev == 1)
4321 nifq = &ifs->ifs_ips_icmpacktq;
4322 else
4323 nifq = &ifs->ifs_ips_icmptq;
4324 break;
4325 case IPPROTO_TCP :
4326 nifq = ifs->ifs_ips_tqtqb + is->is_state[rev];
4327 break;
4328
4329 case IPPROTO_UDP :
4330 if (rev == 1)
4331 nifq = &ifs->ifs_ips_udpacktq;
4332 else
4333 nifq = &ifs->ifs_ips_udptq;
4334 break;
4335
4336 default :
4337 nifq = &ifs->ifs_ips_iptq;
4338 break;
4339 }
4340 }
4341
4342 oifq = is->is_sti.tqe_ifq;
4343 /*
4344 * If it's currently on a timeout queue, move it from one queue to
4345 * another, else put it on the end of the newly determined queue.
4346 */
4347 if (oifq != NULL)
4348 fr_movequeue(&is->is_sti, oifq, nifq, ifs);
4349 else
4350 fr_queueappend(&is->is_sti, nifq, is, ifs);
4351 return;
4352 }
4353
4354
4355 /* ------------------------------------------------------------------------ */
4356 /* Function: fr_stateiter */
4357 /* Returns: int - 0 == success, else error */
4358 /* Parameters: token(I) - pointer to ipftoken structure */
4359 /* itp(I) - pointer to ipfgeniter structure */
4360 /* */
4361 /* This function handles the SIOCGENITER ioctl for the state tables and */
4362 /* walks through the list of entries in the state table list (ips_list.) */
4363 /* ------------------------------------------------------------------------ */
4364 static int fr_stateiter(token, itp, ifs)
4365 ipftoken_t *token;
4366 ipfgeniter_t *itp;
4367 ipf_stack_t *ifs;
4368 {
4369 ipstate_t *is, *next, zero;
4370 int error, count;
4371 char *dst;
4372
4373 if (itp->igi_data == NULL)
4374 return EFAULT;
4375
4376 if (itp->igi_nitems == 0)
4377 return EINVAL;
4378
4379 if (itp->igi_type != IPFGENITER_STATE)
4380 return EINVAL;
4381
4382 error = 0;
4383
4384 READ_ENTER(&ifs->ifs_ipf_state);
4385
4386 /*
4387 * Get "previous" entry from the token and find the next entry.
4388 */
4389 is = token->ipt_data;
4390 if (is == NULL) {
4391 next = ifs->ifs_ips_list;
4392 } else {
4393 next = is->is_next;
4394 }
4395
4396 dst = itp->igi_data;
4397 for (count = itp->igi_nitems; count > 0; count--) {
4398 /*
4399 * If we found an entry, add a reference to it and update the token.
4400 * Otherwise, zero out data to be returned and NULL out token.
4401 */
4402 if (next != NULL) {
4403 MUTEX_ENTER(&next->is_lock);
4404 next->is_ref++;
4405 MUTEX_EXIT(&next->is_lock);
4406 token->ipt_data = next;
4407 } else {
4408 bzero(&zero, sizeof(zero));
4409 next = &zero;
4410 token->ipt_data = NULL;
4411 }
4412
4413 /*
4414 * Safe to release lock now the we have a reference.
4415 */
4416 RWLOCK_EXIT(&ifs->ifs_ipf_state);
4417
4418 /*
4419 * Copy out data and clean up references and tokens.
4420 */
4421 error = COPYOUT(next, dst, sizeof(*next));
4422 if (error != 0)
4423 error = EFAULT;
4424 if (token->ipt_data == NULL) {
4425 ipf_freetoken(token, ifs);
4426 break;
4427 } else {
4428 if (is != NULL)
4429 fr_statederef(&is, ifs);
4430 if (next->is_next == NULL) {
4431 ipf_freetoken(token, ifs);
4432 break;
4433 }
4434 }
4435
4436 if ((count == 1) || (error != 0))
4437 break;
4438
4439 READ_ENTER(&ifs->ifs_ipf_state);
4440 dst += sizeof(*next);
4441 is = next;
4442 next = is->is_next;
4443 }
4444
4445 return error;
4446 }