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__
35struct 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)
115static const char sccsid[] = "@(#)ip_state.c	1.8 6/5/96 (C) 1993-2000 Darren Reed";
116static 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
120static ipstate_t *fr_checkicmp6matchingstate __P((fr_info_t *));
121#endif
122static ipstate_t *fr_matchsrcdst __P((fr_info_t *, ipstate_t *, i6addr_t *,
123				      i6addr_t *, tcphdr_t *, u_32_t));
124static ipstate_t *fr_checkicmpmatchingstate __P((fr_info_t *));
125static int fr_state_flush __P((int, int, ipf_stack_t *));
126static ips_stat_t *fr_statetstats __P((ipf_stack_t *));
127static int fr_state_remove __P((caddr_t, ipf_stack_t *));
128static void fr_ipsmove __P((ipstate_t *, u_int, ipf_stack_t *));
129static int fr_tcpstate __P((fr_info_t *, tcphdr_t *, ipstate_t *));
130static int fr_tcpoptions __P((fr_info_t *, tcphdr_t *, tcpdata_t *));
131static ipstate_t *fr_stclone __P((fr_info_t *, tcphdr_t *, ipstate_t *));
132static void fr_fixinisn __P((fr_info_t *, ipstate_t *));
133static void fr_fixoutisn __P((fr_info_t *, ipstate_t *));
134static void fr_checknewisn __P((fr_info_t *, ipstate_t *));
135static int fr_stateiter __P((ipftoken_t *, ipfgeniter_t *, ipf_stack_t *));
136
137int fr_stputent __P((caddr_t, ipf_stack_t *));
138int 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/* ------------------------------------------------------------------------ */
154int fr_stateinit(ifs)
155ipf_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/* ------------------------------------------------------------------------ */
281void fr_stateunload(ifs)
282ipf_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/* ------------------------------------------------------------------------ */
354static ips_stat_t *fr_statetstats(ifs)
355ipf_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/* ------------------------------------------------------------------------ */
375static int fr_state_remove(data, ifs)
376caddr_t data;
377ipf_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/* ------------------------------------------------------------------------ */
417int fr_state_ioctl(data, cmd, mode, uid, ctx, ifs)
418caddr_t data;
419ioctlcmd_t cmd;
420int mode, uid;
421void *ctx;
422ipf_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/* ------------------------------------------------------------------------ */
610int fr_stgetent(data, ifs)
611caddr_t data;
612ipf_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/* ------------------------------------------------------------------------ */
666int fr_stputent(data, ifs)
667caddr_t data;
668ipf_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/* ------------------------------------------------------------------------ */
803void fr_stinsert(is, rev, ifs)
804ipstate_t *is;
805int rev;
806ipf_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/* ------------------------------------------------------------------------ */
877static int fr_match_ipv4addrs(is1, is2)
878ipstate_t *is1;
879ipstate_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/* ------------------------------------------------------------------------ */
902static int fr_match_ipv6addrs(is1, is2)
903ipstate_t *is1;
904ipstate_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/* ------------------------------------------------------------------------ */
930static int fr_match_addresses(is1, is2)
931ipstate_t *is1;
932ipstate_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/* ------------------------------------------------------------------------ */
955static int fr_match_ppairs(ppairs1, ppairs2)
956port_pair_t *ppairs1;
957port_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/* ------------------------------------------------------------------------ */
983static int fr_match_l4_hdr(is1, is2)
984ipstate_t *is1;
985ipstate_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/* ------------------------------------------------------------------------ */
1072static int fr_matchstates(is1, is2)
1073ipstate_t *is1;
1074ipstate_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/* ------------------------------------------------------------------------ */
1113ipstate_t *fr_addstate(fin, stsave, flags)
1114fr_info_t *fin;
1115ipstate_t **stsave;
1116u_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/* ------------------------------------------------------------------------ */
1547static int fr_tcpoptions(fin, tcp, td)
1548fr_info_t *fin;
1549tcphdr_t *tcp;
1550tcpdata_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/* ------------------------------------------------------------------------ */
1645static int fr_tcpstate(fin, tcp, is)
1646fr_info_t *fin;
1647tcphdr_t *tcp;
1648ipstate_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/* ------------------------------------------------------------------------ */
1758static void fr_checknewisn(fin, is)
1759fr_info_t *fin;
1760ipstate_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/* ------------------------------------------------------------------------ */
1794int fr_tcpinwindow(fin, fdata, tdata, tcp, flags)
1795fr_info_t *fin;
1796tcpdata_t  *fdata, *tdata;
1797tcphdr_t *tcp;
1798int 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/* ------------------------------------------------------------------------ */
2011static ipstate_t *fr_stclone(fin, tcp, is)
2012fr_info_t *fin;
2013tcphdr_t *tcp;
2014ipstate_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/* ------------------------------------------------------------------------ */
2102static ipstate_t *fr_matchsrcdst(fin, is, src, dst, tcp, cmask)
2103fr_info_t *fin;
2104ipstate_t *is;
2105i6addr_t *src, *dst;
2106tcphdr_t *tcp;
2107u_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/* ------------------------------------------------------------------------ */
2364static ipstate_t *fr_checkicmpmatchingstate(fin)
2365fr_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/* ------------------------------------------------------------------------ */
2615static void fr_ipsmove(is, hv, ifs)
2616ipstate_t *is;
2617u_int hv;
2618ipf_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/* ------------------------------------------------------------------------ */
2667ipstate_t *fr_stlookup(fin, tcp, ifqp)
2668fr_info_t *fin;
2669tcphdr_t *tcp;
2670ipftq_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);
2732icmp6again:
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);
2826retry_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/* ------------------------------------------------------------------------ */
2932void fr_updatestate(fin, is, ifq)
2933fr_info_t *fin;
2934ipstate_t *is;
2935ipftq_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/* ------------------------------------------------------------------------ */
2988frentry_t *fr_checkstate(fin, passp)
2989fr_info_t *fin;
2990u_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
3066matched:
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/* ------------------------------------------------------------------------ */
3105static void fr_fixoutisn(fin, is)
3106fr_info_t *fin;
3107ipstate_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/* ------------------------------------------------------------------------ */
3143static void fr_fixinisn(fin, is)
3144fr_info_t *fin;
3145ipstate_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/* ------------------------------------------------------------------------ */
3187void fr_statesync(action, v, ifp, name, ifs)
3188int action, v;
3189void *ifp;
3190char *name;
3191ipf_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/* ------------------------------------------------------------------------ */
3266void fr_stateifindexsync(ifp, newifp, ifs)
3267void *ifp;
3268void *newifp;
3269ipf_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/* ------------------------------------------------------------------------ */
3300int fr_delstate(is, why, ifs)
3301ipstate_t *is;
3302int why;
3303ipf_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/* ------------------------------------------------------------------------ */
3424void fr_timeoutstate(ifs)
3425ipf_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/* ---------------------------------------------------------------------- */
3492static int fr_state_flush(flush_option, proto, ifs)
3493int flush_option, proto;
3494ipf_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/* ------------------------------------------------------------------------ */
3583int fr_tcp_age(tqe, fin, tqtab, flags)
3584ipftqent_t *tqe;
3585fr_info_t *fin;
3586ipftq_t *tqtab;
3587int 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/* ------------------------------------------------------------------------ */
3945void ipstate_log(is, type, ifs)
3946struct ipstate *is;
3947u_int type;
3948ipf_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/* ------------------------------------------------------------------------ */
4018static ipstate_t *fr_checkicmp6matchingstate(fin)
4019fr_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/* ------------------------------------------------------------------------ */
4195void fr_sttab_init(tqp, ifs)
4196ipftq_t *tqp;
4197ipf_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/* ------------------------------------------------------------------------ */
4233void fr_sttab_destroy(tqp)
4234ipftq_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/* ------------------------------------------------------------------------ */
4256void fr_statederef(isp, ifs)
4257ipstate_t **isp;
4258ipf_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/* ------------------------------------------------------------------------ */
4295void fr_setstatequeue(is, rev, ifs)
4296ipstate_t *is;
4297int rev;
4298ipf_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/* ------------------------------------------------------------------------ */
4364static int fr_stateiter(token, itp, ifs)
4365ipftoken_t *token;
4366ipfgeniter_t *itp;
4367ipf_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}
4447