1
2/*
3 * Copyright (C) 2012 by Darren Reed.
4 *
5 * See the IPFILTER.LICENCE file for details on licencing.
6 */
7#if defined(KERNEL) || defined(_KERNEL)
8# undef KERNEL
9# undef _KERNEL
10# define        KERNEL	1
11# define        _KERNEL	1
12#endif
13#include <sys/errno.h>
14#include <sys/types.h>
15#include <sys/param.h>
16#include <sys/time.h>
17#include <sys/file.h>
18# include <sys/fcntl.h>
19#if !defined(_KERNEL) && !defined(__KERNEL__)
20# include <stdio.h>
21# include <string.h>
22# include <stdlib.h>
23# include <ctype.h>
24# define _KERNEL
25# include <sys/uio.h>
26# undef _KERNEL
27#endif
28# include <sys/protosw.h>
29#include <sys/socket.h>
30#if defined(_KERNEL)
31#ifdef __FreeBSD__
32#  include <sys/ctype.h>
33# endif
34# include <sys/systm.h>
35# if !defined(__SVR4)
36#  include <sys/mbuf.h>
37# endif
38#endif
39#if defined(_KERNEL) && defined(__FreeBSD__)
40# include <sys/filio.h>
41# include <sys/fcntl.h>
42#else
43# include <sys/ioctl.h>
44#endif
45#if defined(__SVR4)
46# include <sys/byteorder.h>
47# ifdef _KERNEL
48#  include <sys/dditypes.h>
49# endif
50# include <sys/stream.h>
51# include <sys/kmem.h>
52#endif
53#ifdef __FreeBSD__
54# include <sys/queue.h>
55#endif
56#include <net/if.h>
57#if defined(__FreeBSD__) && defined(_KERNEL)
58#include <net/vnet.h>
59#else
60#define CURVNET_SET(arg)
61#define CURVNET_RESTORE()
62#define	VNET_DEFINE(_t, _v)	_t _v
63#define	VNET_DECLARE(_t, _v)	extern _t _v
64#define	VNET(arg)	arg
65#endif
66#ifdef sun
67# include <net/af.h>
68#endif
69#include <netinet/in.h>
70#include <netinet/in_systm.h>
71#include <netinet/ip.h>
72# include <netinet/ip_var.h>
73#include <netinet/tcp.h>
74#include <netinet/udp.h>
75#include <netinet/ip_icmp.h>
76#include "netinet/ip_compat.h"
77#include <netinet/tcpip.h>
78#include "netinet/ip_fil.h"
79#include "netinet/ip_nat.h"
80#include "netinet/ip_state.h"
81#include "netinet/ip_proxy.h"
82#if defined(__FreeBSD__)
83# include <sys/malloc.h>
84#endif
85
86/* END OF INCLUDES */
87
88#include "netinet/ip_ftp_pxy.c"
89#include "netinet/ip_tftp_pxy.c"
90#include "netinet/ip_rcmd_pxy.c"
91#include "netinet/ip_pptp_pxy.c"
92#if defined(_KERNEL)
93# include "netinet/ip_irc_pxy.c"
94# include "netinet/ip_raudio_pxy.c"
95# include "netinet/ip_netbios_pxy.c"
96#endif
97#include "netinet/ip_ipsec_pxy.c"
98#include "netinet/ip_rpcb_pxy.c"
99
100
101#define	AP_SESS_SIZE	53
102
103static int ipf_proxy_fixseqack(fr_info_t *, ip_t *, ap_session_t *, int );
104static aproxy_t *ipf_proxy_create_clone(ipf_main_softc_t *, aproxy_t *);
105
106typedef struct ipf_proxy_softc_s {
107	int		ips_proxy_debug;
108	int		ips_proxy_session_size;
109	ap_session_t	**ips_sess_tab;
110	ap_session_t	*ips_sess_list;
111	aproxy_t	*ips_proxies;
112	int		ips_init_run;
113	ipftuneable_t	*ipf_proxy_tune;
114} ipf_proxy_softc_t;
115
116static ipftuneable_t ipf_proxy_tuneables[] = {
117	{ { (void *)offsetof(ipf_proxy_softc_t, ips_proxy_debug) },
118		"proxy_debug",	0,	0x1f,
119		stsizeof(ipf_proxy_softc_t, ips_proxy_debug),
120		0,	NULL,	NULL },
121	{ { NULL },		NULL,			0,	0,
122		0,
123		0,	NULL,	NULL}
124};
125
126static	aproxy_t	*ap_proxylist = NULL;
127static	aproxy_t	ips_proxies[] = {
128#ifdef	IPF_FTP_PROXY
129	{ NULL, NULL, "ftp", (char)IPPROTO_TCP, 0, 0, 0,
130	  ipf_p_ftp_main_load, ipf_p_ftp_main_unload,
131	  ipf_p_ftp_soft_create, ipf_p_ftp_soft_destroy,
132	  NULL, NULL,
133	  ipf_p_ftp_new, ipf_p_ftp_del, ipf_p_ftp_in, ipf_p_ftp_out, NULL,
134	  NULL, NULL, NULL, NULL },
135#endif
136#ifdef	IPF_TFTP_PROXY
137	{ NULL, NULL, "tftp", (char)IPPROTO_UDP, 0, 0, 0,
138	  ipf_p_tftp_main_load, ipf_p_tftp_main_unload,
139	  ipf_p_tftp_soft_create, ipf_p_tftp_soft_destroy,
140	  NULL, NULL,
141	  ipf_p_tftp_new, ipf_p_tftp_del,
142	  ipf_p_tftp_in, ipf_p_tftp_out, NULL,
143	  NULL, NULL, NULL, NULL },
144#endif
145#ifdef	IPF_IRC_PROXY
146	{ NULL, NULL, "irc", (char)IPPROTO_TCP, 0, 0, 0,
147	  ipf_p_irc_main_load, ipf_p_irc_main_unload,
148	  NULL, NULL,
149	  NULL, NULL,
150	  ipf_p_irc_new, NULL, NULL, ipf_p_irc_out, NULL,
151	  NULL, NULL, NULL, NULL },
152#endif
153#ifdef	IPF_RCMD_PROXY
154	{ NULL, NULL, "rcmd", (char)IPPROTO_TCP, 0, 0, 0,
155	  ipf_p_rcmd_main_load, ipf_p_rcmd_main_unload,
156	  NULL, NULL,
157	  NULL, NULL,
158	  ipf_p_rcmd_new, ipf_p_rcmd_del,
159	  ipf_p_rcmd_in, ipf_p_rcmd_out, NULL,
160	  NULL, NULL, NULL, NULL },
161#endif
162#ifdef	IPF_RAUDIO_PROXY
163	{ NULL, NULL, "raudio", (char)IPPROTO_TCP, 0, 0, 0,
164	  ipf_p_raudio_main_load, ipf_p_raudio_main_unload,
165	  NULL, NULL,
166	  NULL, NULL,
167	  ipf_p_raudio_new, NULL, ipf_p_raudio_in, ipf_p_raudio_out, NULL,
168	  NULL, NULL, NULL, NULL },
169#endif
170#ifdef	IPF_MSNRPC_PROXY
171	{ NULL, NULL, "msnrpc", (char)IPPROTO_TCP, 0, 0, 0,
172	  ipf_p_msnrpc_init, ipf_p_msnrpc_fini,
173	  NULL, NULL,
174	  NULL, NULL,
175	  ipf_p_msnrpc_new, NULL, ipf_p_msnrpc_in, ipf_p_msnrpc_out, NULL,
176	  NULL, NULL, NULL, NULL },
177#endif
178#ifdef	IPF_NETBIOS_PROXY
179	{ NULL, NULL, "netbios", (char)IPPROTO_UDP, 0, 0, 0,
180	  ipf_p_netbios_main_load, ipf_p_netbios_main_unload,
181	  NULL, NULL,
182	  NULL, NULL,
183	  NULL, NULL, NULL, ipf_p_netbios_out, NULL,
184	  NULL, NULL, NULL, NULL },
185#endif
186#ifdef	IPF_IPSEC_PROXY
187	{ NULL, NULL, "ipsec", (char)IPPROTO_UDP, 0, 0, 0,
188	  NULL, NULL,
189	  ipf_p_ipsec_soft_create, ipf_p_ipsec_soft_destroy,
190	  ipf_p_ipsec_soft_init, ipf_p_ipsec_soft_fini,
191	  ipf_p_ipsec_new, ipf_p_ipsec_del,
192	  ipf_p_ipsec_inout, ipf_p_ipsec_inout, ipf_p_ipsec_match,
193	  NULL, NULL, NULL, NULL },
194#endif
195#ifdef	IPF_DNS_PROXY
196	{ NULL, NULL, "dns", (char)IPPROTO_UDP, 0, 0, 0,
197	  NULL, NULL,
198	  ipf_p_dns_soft_create, ipf_p_dns_soft_destroy,
199	  NULL, NULL,
200	  ipf_p_dns_new, ipf_p_ipsec_del,
201	  ipf_p_dns_inout, ipf_p_dns_inout, ipf_p_dns_match,
202	  ipf_p_dns_ctl, NULL, NULL, NULL },
203#endif
204#ifdef	IPF_PPTP_PROXY
205	{ NULL, NULL, "pptp", (char)IPPROTO_TCP, 0, 0, 0,
206	  ipf_p_pptp_main_load, ipf_p_pptp_main_unload,
207	  NULL, NULL,
208	  NULL, NULL,
209	  ipf_p_pptp_new, ipf_p_pptp_del,
210	  ipf_p_pptp_inout, ipf_p_pptp_inout, NULL,
211	  NULL, NULL, NULL, NULL },
212#endif
213#ifdef	IPF_RPCB_PROXY
214# ifndef _KERNEL
215	{ NULL, NULL, "rpcbt", (char)IPPROTO_TCP, 0, 0, 0,
216	  NULL, NULL,
217	  NULL, NULL,
218	  NULL, NULL,
219	  ipf_p_rpcb_new, ipf_p_rpcb_del,
220	  ipf_p_rpcb_in, ipf_p_rpcb_out, NULL,
221	  NULL, NULL, NULL, NULL },
222# endif
223	{ NULL, NULL, "rpcbu", (char)IPPROTO_UDP, 0, 0, 0,
224	  ipf_p_rpcb_main_load, ipf_p_rpcb_main_unload,
225	  NULL, NULL,
226	  NULL, NULL,
227	  ipf_p_rpcb_new, ipf_p_rpcb_del,
228	  ipf_p_rpcb_in, ipf_p_rpcb_out, NULL,
229	  NULL, NULL, NULL, NULL },
230#endif
231	{ NULL, NULL, "", '\0', 0, 0, 0,
232	  NULL, NULL,
233	  NULL, NULL,
234	  NULL, NULL,
235	  NULL, NULL,
236	  NULL, NULL, NULL,
237	  NULL, NULL, NULL, NULL }
238};
239
240
241/* ------------------------------------------------------------------------ */
242/* Function:    ipf_proxy_main_load                                         */
243/* Returns:     int    - 0 == success, else failure.                        */
244/* Parameters:  Nil                                                         */
245/*                                                                          */
246/* Initialise hook for kernel application proxies.                          */
247/* Call the initialise routine for all the compiled in kernel proxies.      */
248/* ------------------------------------------------------------------------ */
249int
250ipf_proxy_main_load(void)
251{
252	aproxy_t *ap;
253
254	for (ap = ips_proxies; ap->apr_p; ap++) {
255		if (ap->apr_load != NULL)
256			(*ap->apr_load)();
257	}
258	return (0);
259}
260
261
262/* ------------------------------------------------------------------------ */
263/* Function:    ipf_proxy_main_unload                                       */
264/* Returns:     int - 0 == success, else failure.                           */
265/* Parameters:  Nil                                                         */
266/*                                                                          */
267/* Unload hook for kernel application proxies.                              */
268/* Call the finialise routine for all the compiled in kernel proxies.       */
269/* ------------------------------------------------------------------------ */
270int
271ipf_proxy_main_unload(void)
272{
273	aproxy_t *ap;
274
275	for (ap = ips_proxies; ap->apr_p; ap++)
276		if (ap->apr_unload != NULL)
277			(*ap->apr_unload)();
278	for (ap = ap_proxylist; ap; ap = ap->apr_next)
279		if (ap->apr_unload != NULL)
280			(*ap->apr_unload)();
281
282	return (0);
283}
284
285
286/* ------------------------------------------------------------------------ */
287/* Function:    ipf_proxy_soft_create                                       */
288/* Returns:     void *   -                                                  */
289/* Parameters:  softc(I) - pointer to soft context main structure           */
290/*                                                                          */
291/* Build the structure to hold all of the run time data to support proxies. */
292/* ------------------------------------------------------------------------ */
293void *
294ipf_proxy_soft_create(ipf_main_softc_t *softc)
295{
296	ipf_proxy_softc_t *softp;
297	aproxy_t *last;
298	aproxy_t *apn;
299	aproxy_t *ap;
300
301	KMALLOC(softp, ipf_proxy_softc_t *);
302	if (softp == NULL)
303		return (softp);
304
305	bzero((char *)softp, sizeof(*softp));
306
307#if defined(_KERNEL)
308	softp->ips_proxy_debug = 0;
309#else
310	softp->ips_proxy_debug = 2;
311#endif
312	softp->ips_proxy_session_size = AP_SESS_SIZE;
313
314	softp->ipf_proxy_tune = ipf_tune_array_copy(softp,
315						    sizeof(ipf_proxy_tuneables),
316						    ipf_proxy_tuneables);
317	if (softp->ipf_proxy_tune == NULL) {
318		ipf_proxy_soft_destroy(softc, softp);
319		return (NULL);
320	}
321	if (ipf_tune_array_link(softc, softp->ipf_proxy_tune) == -1) {
322		ipf_proxy_soft_destroy(softc, softp);
323		return (NULL);
324	}
325
326	last = NULL;
327	for (ap = ips_proxies; ap->apr_p; ap++) {
328		apn = ipf_proxy_create_clone(softc, ap);
329		if (apn == NULL)
330			goto failed;
331		if (last != NULL)
332			last->apr_next = apn;
333		else
334			softp->ips_proxies = apn;
335		last = apn;
336	}
337	for (ap = ips_proxies; ap != NULL; ap = ap->apr_next) {
338		apn = ipf_proxy_create_clone(softc, ap);
339		if (apn == NULL)
340			goto failed;
341		if (last != NULL)
342			last->apr_next = apn;
343		else
344			softp->ips_proxies = apn;
345		last = apn;
346	}
347
348	return (softp);
349failed:
350	ipf_proxy_soft_destroy(softc, softp);
351	return (NULL);
352}
353
354
355/* ------------------------------------------------------------------------ */
356/* Function:    ipf_proxy_soft_create                                       */
357/* Returns:     void *   -                                                  */
358/* Parameters:  softc(I) - pointer to soft context main structure           */
359/*              orig(I)  - pointer to proxy definition to copy              */
360/*                                                                          */
361/* This function clones a proxy definition given by orig and returns a      */
362/* a pointer to that copy.                                                  */
363/* ------------------------------------------------------------------------ */
364static aproxy_t *
365ipf_proxy_create_clone(ipf_main_softc_t *softc, aproxy_t *orig)
366{
367	aproxy_t *apn;
368
369	KMALLOC(apn, aproxy_t *);
370	if (apn == NULL)
371		return (NULL);
372
373	bcopy((char *)orig, (char *)apn, sizeof(*apn));
374	apn->apr_next = NULL;
375	apn->apr_soft = NULL;
376
377	if (apn->apr_create != NULL) {
378		apn->apr_soft = (*apn->apr_create)(softc);
379		if (apn->apr_soft == NULL) {
380			KFREE(apn);
381			return (NULL);
382		}
383	}
384
385	apn->apr_parent = orig;
386	orig->apr_clones++;
387
388	return (apn);
389}
390
391
392/* ------------------------------------------------------------------------ */
393/* Function:    ipf_proxy_soft_create                                       */
394/* Returns:     int      - 0 == success, else failure.                      */
395/* Parameters:  softc(I) - pointer to soft context main structure           */
396/*              arg(I)   - pointer to proxy contect data                    */
397/*                                                                          */
398/* Initialise the proxy context and walk through each of the proxies and    */
399/* call its initialisation function. This allows for proxies to do any      */
400/* local setup prior to actual use.                                         */
401/* ------------------------------------------------------------------------ */
402int
403ipf_proxy_soft_init(ipf_main_softc_t *softc, void *arg)
404{
405	ipf_proxy_softc_t *softp;
406	aproxy_t *ap;
407	u_int size;
408	int err;
409
410	softp = arg;
411	size = softp->ips_proxy_session_size * sizeof(ap_session_t *);
412
413	KMALLOCS(softp->ips_sess_tab, ap_session_t **, size);
414
415	if (softp->ips_sess_tab == NULL)
416		return (-1);
417
418	bzero(softp->ips_sess_tab, size);
419
420	for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next) {
421		if (ap->apr_init != NULL) {
422			err = (*ap->apr_init)(softc, ap->apr_soft);
423			if (err != 0)
424				return (-2);
425		}
426	}
427	softp->ips_init_run = 1;
428
429	return (0);
430}
431
432
433/* ------------------------------------------------------------------------ */
434/* Function:    ipf_proxy_soft_create                                       */
435/* Returns:     int      - 0 == success, else failure.                      */
436/* Parameters:  softc(I) - pointer to soft context main structure           */
437/*              arg(I)   - pointer to proxy contect data                    */
438/*                                                                          */
439/* This function should always succeed. It is responsible for ensuring that */
440/* the proxy context can be safely called when ipf_proxy_soft_destroy is    */
441/* called and suring all of the proxies have similarly been instructed.     */
442/* ------------------------------------------------------------------------ */
443int
444ipf_proxy_soft_fini(ipf_main_softc_t *softc, void *arg)
445{
446	ipf_proxy_softc_t *softp = arg;
447	aproxy_t *ap;
448
449	for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next) {
450		if (ap->apr_fini != NULL) {
451			(*ap->apr_fini)(softc, ap->apr_soft);
452		}
453	}
454
455	if (softp->ips_sess_tab != NULL) {
456		KFREES(softp->ips_sess_tab,
457		       softp->ips_proxy_session_size * sizeof(ap_session_t *));
458		softp->ips_sess_tab = NULL;
459	}
460	softp->ips_init_run = 0;
461
462	return (0);
463}
464
465
466/* ------------------------------------------------------------------------ */
467/* Function:    ipf_proxy_soft_destroy                                      */
468/* Returns:     Nil                                                         */
469/* Parameters:  softc(I) - pointer to soft context main structure           */
470/*              arg(I)   - pointer to proxy contect data                    */
471/*                                                                          */
472/* Free up all of the local data structures allocated during creation.      */
473/* ------------------------------------------------------------------------ */
474void
475ipf_proxy_soft_destroy(ipf_main_softc_t *softc, void *arg)
476{
477	ipf_proxy_softc_t *softp = arg;
478	aproxy_t *ap;
479
480	while ((ap = softp->ips_proxies) != NULL) {
481		softp->ips_proxies = ap->apr_next;
482		if (ap->apr_destroy != NULL)
483			(*ap->apr_destroy)(softc, ap->apr_soft);
484		ap->apr_parent->apr_clones--;
485		KFREE(ap);
486	}
487
488	if (softp->ipf_proxy_tune != NULL) {
489		ipf_tune_array_unlink(softc, softp->ipf_proxy_tune);
490		KFREES(softp->ipf_proxy_tune, sizeof(ipf_proxy_tuneables));
491		softp->ipf_proxy_tune = NULL;
492	}
493
494	KFREE(softp);
495}
496
497
498/* ------------------------------------------------------------------------ */
499/* Function:    ipf_proxy_flush                                             */
500/* Returns:     Nil                                                         */
501/* Parameters:  arg(I)   - pointer to proxy contect data                    */
502/*              how(I)   - indicates the type of flush operation            */
503/*                                                                          */
504/* Walk through all of the proxies and pass on the flush command as either  */
505/* a flush or a clear.                                                      */
506/* ------------------------------------------------------------------------ */
507void
508ipf_proxy_flush(void *arg, int how)
509{
510	ipf_proxy_softc_t *softp = arg;
511	aproxy_t *ap;
512
513	switch (how)
514	{
515	case 0 :
516		for (ap = softp->ips_proxies; ap; ap = ap->apr_next)
517			if (ap->apr_flush != NULL)
518				(*ap->apr_flush)(ap, how);
519		break;
520	case 1 :
521		for (ap = softp->ips_proxies; ap; ap = ap->apr_next)
522			if (ap->apr_clear != NULL)
523				(*ap->apr_clear)(ap);
524		break;
525	default :
526		break;
527	}
528}
529
530
531/* ------------------------------------------------------------------------ */
532/* Function:    ipf_proxy_add                                               */
533/* Returns:     int   - 0 == success, else failure.                         */
534/* Parameters:  ap(I) - pointer to proxy structure                          */
535/*                                                                          */
536/* Dynamically add a new kernel proxy.  Ensure that it is unique in the     */
537/* collection compiled in and dynamically added.                            */
538/* ------------------------------------------------------------------------ */
539int
540ipf_proxy_add(void *arg, aproxy_t *ap)
541{
542	ipf_proxy_softc_t *softp = arg;
543
544	aproxy_t *a;
545
546	for (a = ips_proxies; a->apr_p; a++)
547		if ((a->apr_p == ap->apr_p) &&
548		    !strncmp(a->apr_label, ap->apr_label,
549			     sizeof(ap->apr_label))) {
550			if (softp->ips_proxy_debug & 0x01)
551				printf("ipf_proxy_add: %s/%d present (B)\n",
552				       a->apr_label, a->apr_p);
553			return (-1);
554		}
555
556	for (a = ap_proxylist; (a != NULL); a = a->apr_next)
557		if ((a->apr_p == ap->apr_p) &&
558		    !strncmp(a->apr_label, ap->apr_label,
559			     sizeof(ap->apr_label))) {
560			if (softp->ips_proxy_debug & 0x01)
561				printf("ipf_proxy_add: %s/%d present (D)\n",
562				       a->apr_label, a->apr_p);
563			return (-1);
564		}
565	ap->apr_next = ap_proxylist;
566	ap_proxylist = ap;
567	if (ap->apr_load != NULL)
568		(*ap->apr_load)();
569	return (0);
570}
571
572
573/* ------------------------------------------------------------------------ */
574/* Function:    ipf_proxy_ctl                                               */
575/* Returns:     int    - 0 == success, else error                           */
576/* Parameters:  softc(I) - pointer to soft context main structure           */
577/*              arg(I)   - pointer to proxy context                         */
578/*              ctl(I)   - pointer to proxy control structure               */
579/*                                                                          */
580/* Check to see if the proxy this control request has come through for      */
581/* exists, and if it does and it has a control function then invoke that    */
582/* control function.                                                        */
583/* ------------------------------------------------------------------------ */
584int
585ipf_proxy_ctl(ipf_main_softc_t *softc, void *arg, ap_ctl_t *ctl)
586{
587	ipf_proxy_softc_t *softp = arg;
588	aproxy_t *a;
589	int error;
590
591	a = ipf_proxy_lookup(arg, ctl->apc_p, ctl->apc_label);
592	if (a == NULL) {
593		if (softp->ips_proxy_debug & 0x01)
594			printf("ipf_proxy_ctl: can't find %s/%d\n",
595				ctl->apc_label, ctl->apc_p);
596		IPFERROR(80001);
597		error = ESRCH;
598	} else if (a->apr_ctl == NULL) {
599		if (softp->ips_proxy_debug & 0x01)
600			printf("ipf_proxy_ctl: no ctl function for %s/%d\n",
601				ctl->apc_label, ctl->apc_p);
602		IPFERROR(80002);
603		error = ENXIO;
604	} else {
605		error = (*a->apr_ctl)(softc, a->apr_soft, ctl);
606		if ((error != 0) && (softp->ips_proxy_debug & 0x02))
607			printf("ipf_proxy_ctl: %s/%d ctl error %d\n",
608				a->apr_label, a->apr_p, error);
609	}
610	return (error);
611}
612
613
614/* ------------------------------------------------------------------------ */
615/* Function:    ipf_proxy_del                                               */
616/* Returns:     int   - 0 == success, else failure.                         */
617/* Parameters:  ap(I) - pointer to proxy structure                          */
618/*                                                                          */
619/* Delete a proxy that has been added dynamically from those available.     */
620/* If it is in use, return 1 (do not destroy NOW), not in use 0 or -1       */
621/* if it cannot be matched.                                                 */
622/* ------------------------------------------------------------------------ */
623int
624ipf_proxy_del(aproxy_t *ap)
625{
626	aproxy_t *a, **app;
627
628	for (app = &ap_proxylist; ((a = *app) != NULL); app = &a->apr_next) {
629		if (a == ap) {
630			a->apr_flags |= APR_DELETE;
631			if (ap->apr_ref == 0 && ap->apr_clones == 0) {
632				*app = a->apr_next;
633				return (0);
634			}
635			return (1);
636		}
637	}
638
639	return (-1);
640}
641
642
643/* ------------------------------------------------------------------------ */
644/* Function:    ipf_proxy_ok                                                */
645/* Returns:     int    - 1 == good match else not.                          */
646/* Parameters:  fin(I) - pointer to packet information                      */
647/*              tcp(I) - pointer to TCP/UDP header                          */
648/*              nat(I) - pointer to current NAT session                     */
649/*                                                                          */
650/* This function extends the NAT matching to ensure that a packet that has  */
651/* arrived matches the proxy information attached to the NAT rule. Notably, */
652/* if the proxy is scheduled to be deleted then packets will not match the  */
653/* rule even if the rule is still active.                                   */
654/* ------------------------------------------------------------------------ */
655int
656ipf_proxy_ok(fr_info_t *fin, tcphdr_t *tcp, ipnat_t *np)
657{
658	aproxy_t *apr = np->in_apr;
659	u_short dport = np->in_odport;
660
661	if ((apr == NULL) || (apr->apr_flags & APR_DELETE) ||
662	    (fin->fin_p != apr->apr_p))
663		return (0);
664	if ((tcp == NULL) && dport)
665		return (0);
666	return (1);
667}
668
669
670/* ------------------------------------------------------------------------ */
671/* Function:    ipf_proxy_ioctl                                             */
672/* Returns:     int    - 0 == success, else error                           */
673/* Parameters:  softc(I) - pointer to soft context main structure           */
674/*              data(I)  - pointer to ioctl data                            */
675/*              cmd(I)   - ioctl command                                    */
676/*              mode(I)  - mode bits for device                             */
677/*              ctx(I)   - pointer to context information                   */
678/*                                                                          */
679/* ------------------------------------------------------------------------ */
680int
681ipf_proxy_ioctl(ipf_main_softc_t *softc, caddr_t data, ioctlcmd_t cmd,
682	int mode, void *ctx)
683{
684	ap_ctl_t ctl;
685	caddr_t ptr;
686	int error;
687
688	mode = mode;	/* LINT */
689
690	switch (cmd)
691	{
692	case SIOCPROXY :
693		error = ipf_inobj(softc, data, NULL, &ctl, IPFOBJ_PROXYCTL);
694		if (error != 0) {
695			return (error);
696		}
697		ptr = NULL;
698
699		if (ctl.apc_dsize > 0) {
700			KMALLOCS(ptr, caddr_t, ctl.apc_dsize);
701			if (ptr == NULL) {
702				IPFERROR(80003);
703				error = ENOMEM;
704			} else {
705				error = copyinptr(softc, ctl.apc_data, ptr,
706						  ctl.apc_dsize);
707				if (error == 0)
708					ctl.apc_data = ptr;
709			}
710		} else {
711			ctl.apc_data = NULL;
712			error = 0;
713		}
714
715		if (error == 0)
716			error = ipf_proxy_ctl(softc, softc->ipf_proxy_soft,
717					      &ctl);
718
719		if ((error != 0) && (ptr != NULL)) {
720			KFREES(ptr, ctl.apc_dsize);
721		}
722		break;
723
724	default :
725		IPFERROR(80004);
726		error = EINVAL;
727	}
728	return (error);
729}
730
731
732/* ------------------------------------------------------------------------ */
733/* Function:    ipf_proxy_match                                             */
734/* Returns:     int    - 0 == success, else error                           */
735/* Parameters:  fin(I) - pointer to packet information                      */
736/*              nat(I) - pointer to current NAT session                     */
737/*                                                                          */
738/* If a proxy has a match function, call that to do extended packet         */
739/* matching. Whilst other parts of the NAT code are rather lenient when it  */
740/* comes to the quality of the packet that it will transform, the proxy     */
741/* matching is not because they need to work with data, not just headers.   */
742/* ------------------------------------------------------------------------ */
743int
744ipf_proxy_match(fr_info_t *fin, nat_t *nat)
745{
746	ipf_main_softc_t *softc = fin->fin_main_soft;
747	ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
748	aproxy_t *apr;
749	ipnat_t *ipn;
750	int result;
751
752	ipn = nat->nat_ptr;
753	if (softp->ips_proxy_debug & 0x04)
754		printf("ipf_proxy_match(%lx,%lx) aps %lx ptr %lx\n",
755			(u_long)fin, (u_long)nat, (u_long)nat->nat_aps,
756			(u_long)ipn);
757
758	if ((fin->fin_flx & (FI_SHORT|FI_BAD)) != 0) {
759		if (softp->ips_proxy_debug & 0x08)
760			printf("ipf_proxy_match: flx 0x%x (BAD|SHORT)\n",
761				fin->fin_flx);
762		return (-1);
763	}
764
765	apr = ipn->in_apr;
766	if ((apr == NULL) || (apr->apr_flags & APR_DELETE)) {
767		if (softp->ips_proxy_debug & 0x08)
768			printf("ipf_proxy_match:apr %lx apr_flags 0x%x\n",
769				(u_long)apr, apr ? apr->apr_flags : 0);
770		return (-1);
771	}
772
773	if (apr->apr_match != NULL) {
774		result = (*apr->apr_match)(fin, nat->nat_aps, nat);
775		if (result != 0) {
776			if (softp->ips_proxy_debug & 0x08)
777				printf("ipf_proxy_match: result %d\n", result);
778			return (-1);
779		}
780	}
781	return (0);
782}
783
784
785/* ------------------------------------------------------------------------ */
786/* Function:    ipf_proxy_new                                               */
787/* Returns:     int    - 0 == success, else error                           */
788/* Parameters:  fin(I) - pointer to packet information                      */
789/*              nat(I) - pointer to current NAT session                     */
790/*                                                                          */
791/* Allocate a new application proxy structure and fill it in with the       */
792/* relevant details.  call the init function once complete, prior to        */
793/* returning.                                                               */
794/* ------------------------------------------------------------------------ */
795int
796ipf_proxy_new(fr_info_t *fin, nat_t *nat)
797{
798	ipf_main_softc_t *softc = fin->fin_main_soft;
799	ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
800	register ap_session_t *aps;
801	aproxy_t *apr;
802
803	if (softp->ips_proxy_debug & 0x04)
804		printf("ipf_proxy_new(%lx,%lx) \n", (u_long)fin, (u_long)nat);
805
806	if ((nat->nat_ptr == NULL) || (nat->nat_aps != NULL)) {
807		if (softp->ips_proxy_debug & 0x08)
808			printf("ipf_proxy_new: nat_ptr %lx nat_aps %lx\n",
809				(u_long)nat->nat_ptr, (u_long)nat->nat_aps);
810		return (-1);
811	}
812
813	apr = nat->nat_ptr->in_apr;
814
815	if ((apr->apr_flags & APR_DELETE) ||
816	    (fin->fin_p != apr->apr_p)) {
817		if (softp->ips_proxy_debug & 0x08)
818			printf("ipf_proxy_new: apr_flags 0x%x p %d/%d\n",
819				apr->apr_flags, fin->fin_p, apr->apr_p);
820		return (-1);
821	}
822
823	KMALLOC(aps, ap_session_t *);
824	if (!aps) {
825		if (softp->ips_proxy_debug & 0x08)
826			printf("ipf_proxy_new: malloc failed (%lu)\n",
827				(u_long)sizeof(ap_session_t));
828		return (-1);
829	}
830
831	bzero((char *)aps, sizeof(*aps));
832	aps->aps_data = NULL;
833	aps->aps_apr = apr;
834	aps->aps_psiz = 0;
835	if (apr->apr_new != NULL)
836		if ((*apr->apr_new)(apr->apr_soft, fin, aps, nat) == -1) {
837			if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) {
838				KFREES(aps->aps_data, aps->aps_psiz);
839			}
840			KFREE(aps);
841			if (softp->ips_proxy_debug & 0x08)
842				printf("ipf_proxy_new: new(%lx) failed\n",
843					(u_long)apr->apr_new);
844			return (-1);
845		}
846	aps->aps_nat = nat;
847	aps->aps_next = softp->ips_sess_list;
848	softp->ips_sess_list = aps;
849	nat->nat_aps = aps;
850
851	return (0);
852}
853
854
855/* ------------------------------------------------------------------------ */
856/* Function:    ipf_proxy_check                                             */
857/* Returns:     int - -1 == error, 1 == success                             */
858/* Parameters:  fin(I) - pointer to packet information                      */
859/*              nat(I) - pointer to current NAT session                     */
860/*                                                                          */
861/* Check to see if a packet should be passed through an active proxy        */
862/* routine if one has been setup for it.  We don't need to check the        */
863/* checksum here if IPFILTER_CKSUM is defined because if it is, a failed    */
864/* check causes FI_BAD to be set.                                           */
865/* ------------------------------------------------------------------------ */
866int
867ipf_proxy_check(fr_info_t *fin, nat_t *nat)
868{
869	ipf_main_softc_t *softc = fin->fin_main_soft;
870	ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
871#if SOLARIS && defined(_KERNEL) && defined(ICK_VALID)
872	mb_t *m;
873#endif
874	tcphdr_t *tcp = NULL;
875	udphdr_t *udp = NULL;
876	ap_session_t *aps;
877	aproxy_t *apr;
878	short adjlen;
879	int dosum;
880	ip_t *ip;
881	short rv;
882	int err;
883#if !defined(_KERNEL) || SOLARIS || defined(__FreeBSD__)
884	u_32_t s1, s2, sd;
885#endif
886
887	if (fin->fin_flx & FI_BAD) {
888		if (softp->ips_proxy_debug & 0x08)
889			printf("ipf_proxy_check: flx 0x%x (BAD)\n",
890			       fin->fin_flx);
891		return (-1);
892	}
893
894#ifndef IPFILTER_CKSUM
895	if ((fin->fin_out == 0) && (ipf_checkl4sum(fin) == -1)) {
896		if (softp->ips_proxy_debug & 0x08)
897			printf("ipf_proxy_check: l4 checksum failure %d\n",
898				fin->fin_p);
899		if (fin->fin_p == IPPROTO_TCP)
900			softc->ipf_stats[fin->fin_out].fr_tcpbad++;
901		return (-1);
902	}
903#endif
904
905	aps = nat->nat_aps;
906	if (aps != NULL) {
907		/*
908		 * If there is data in this packet to be proxied then try and
909		 * get it all into the one buffer, else drop it.
910		 */
911#if SOLARIS || defined(HAVE_M_PULLDOWN)
912		if ((fin->fin_dlen > 0) && !(fin->fin_flx & FI_COALESCE))
913			if (ipf_coalesce(fin) == -1) {
914				if (softp->ips_proxy_debug & 0x08)
915					printf("ipf_proxy_check: %s %x\n",
916					       "coalesce failed", fin->fin_flx);
917				return (-1);
918			}
919#endif
920		ip = fin->fin_ip;
921		if (fin->fin_cksum > FI_CK_SUMOK)
922			dosum = 0;
923		else
924			dosum = 1;
925
926		switch (fin->fin_p)
927		{
928		case IPPROTO_TCP :
929			tcp = (tcphdr_t *)fin->fin_dp;
930#if SOLARIS && defined(_KERNEL) && defined(ICK_VALID)
931			m = fin->fin_qfm;
932			if (dohwcksum && (m->b_ick_flag == ICK_VALID))
933				dosum = 0;
934#endif
935			break;
936		case IPPROTO_UDP :
937			udp = (udphdr_t *)fin->fin_dp;
938			break;
939		default :
940			break;
941		}
942
943		apr = aps->aps_apr;
944		err = 0;
945		if (fin->fin_out != 0) {
946			if (apr->apr_outpkt != NULL)
947				err = (*apr->apr_outpkt)(apr->apr_soft, fin,
948							 aps, nat);
949		} else {
950			if (apr->apr_inpkt != NULL)
951				err = (*apr->apr_inpkt)(apr->apr_soft, fin,
952							aps, nat);
953		}
954
955		rv = APR_EXIT(err);
956		if (((softp->ips_proxy_debug & 0x08) && (rv != 0)) ||
957		    (softp->ips_proxy_debug & 0x04))
958			printf("ipf_proxy_check: out %d err %x rv %d\n",
959				fin->fin_out, err, rv);
960		if (rv == 1)
961			return (-1);
962
963		if (rv == 2) {
964			ipf_proxy_deref(apr);
965			nat->nat_aps = NULL;
966			return (-1);
967		}
968
969		/*
970		 * If err != 0 then the data size of the packet has changed
971		 * so we need to recalculate the header checksums for the
972		 * packet.
973		 */
974		adjlen = APR_INC(err);
975#if !defined(_KERNEL) || SOLARIS || defined(__FreeBSD__)
976		s1 = LONG_SUM(fin->fin_plen - adjlen);
977		s2 = LONG_SUM(fin->fin_plen);
978		CALC_SUMD(s1, s2, sd);
979		if ((err != 0) && (fin->fin_cksum < FI_CK_L4PART) &&
980		    fin->fin_v == 4)
981			ipf_fix_outcksum(0, &ip->ip_sum, sd, 0);
982#endif
983		if (fin->fin_flx & FI_DOCKSUM)
984			dosum = 1;
985
986		/*
987		 * For TCP packets, we may need to adjust the sequence and
988		 * acknowledgement numbers to reflect changes in size of the
989		 * data stream.
990		 *
991		 * For both TCP and UDP, recalculate the layer 4 checksum,
992		 * regardless, as we can't tell (here) if data has been
993		 * changed or not.
994		 */
995		if (tcp != NULL) {
996			err = ipf_proxy_fixseqack(fin, ip, aps, adjlen);
997			if (fin->fin_cksum == FI_CK_L4PART) {
998				u_short sum = ntohs(tcp->th_sum);
999				sum += adjlen;
1000				tcp->th_sum = htons(sum);
1001			} else if (fin->fin_cksum < FI_CK_L4PART) {
1002				tcp->th_sum = fr_cksum(fin, ip,
1003						       IPPROTO_TCP, tcp);
1004			}
1005		} else if ((udp != NULL) && (udp->uh_sum != 0)) {
1006			if (fin->fin_cksum == FI_CK_L4PART) {
1007				u_short sum = ntohs(udp->uh_sum);
1008				sum += adjlen;
1009				udp->uh_sum = htons(sum);
1010			} else if (dosum) {
1011				udp->uh_sum = fr_cksum(fin, ip,
1012						       IPPROTO_UDP, udp);
1013			}
1014		}
1015		aps->aps_bytes += fin->fin_plen;
1016		aps->aps_pkts++;
1017	}
1018	return (1);
1019}
1020
1021
1022/* ------------------------------------------------------------------------ */
1023/* Function:    ipf_proxy_lookup                                            */
1024/* Returns:     int - -1 == error, 0 == success                             */
1025/* Parameters:  arg(I)  - pointer to proxy context information              */
1026/*              pr(I)   - protocol number for proxy                         */
1027/*              name(I) - proxy name                                        */
1028/*                                                                          */
1029/* Search for a proxy by the protocol being used and by its name.           */
1030/* ------------------------------------------------------------------------ */
1031aproxy_t *
1032ipf_proxy_lookup(void *arg, u_int pr, char *name)
1033{
1034	ipf_proxy_softc_t *softp = arg;
1035	aproxy_t *ap;
1036
1037	if (softp->ips_proxy_debug & 0x04)
1038		printf("ipf_proxy_lookup(%d,%s)\n", pr, name);
1039
1040	for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next)
1041		if ((ap->apr_p == pr) &&
1042		    !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) {
1043			ap->apr_ref++;
1044			return (ap);
1045		}
1046
1047	if (softp->ips_proxy_debug & 0x08)
1048		printf("ipf_proxy_lookup: failed for %d/%s\n", pr, name);
1049	return (NULL);
1050}
1051
1052
1053/* ------------------------------------------------------------------------ */
1054/* Function:    ipf_proxy_deref                                             */
1055/* Returns:     Nil                                                         */
1056/* Parameters:  ap(I) - pointer to proxy structure                          */
1057/*                                                                          */
1058/* Drop the reference counter associated with the proxy.                    */
1059/* ------------------------------------------------------------------------ */
1060void
1061ipf_proxy_deref(aproxy_t *ap)
1062{
1063	ap->apr_ref--;
1064}
1065
1066
1067/* ------------------------------------------------------------------------ */
1068/* Function:    ipf_proxy_free                                              */
1069/* Returns:     Nil                                                         */
1070/* Parameters:  softc(I) - pointer to soft context main structure           */
1071/*              aps(I)   - pointer to current proxy session                 */
1072/* Locks Held:  ipf_nat_new, ipf_nat(W)                                     */
1073/*                                                                          */
1074/* Free up proxy session information allocated to be used with a NAT        */
1075/* session.                                                                 */
1076/* ------------------------------------------------------------------------ */
1077void
1078ipf_proxy_free(ipf_main_softc_t *softc, ap_session_t *aps)
1079{
1080	ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
1081	ap_session_t *a, **ap;
1082	aproxy_t *apr;
1083
1084	if (!aps)
1085		return;
1086
1087	for (ap = &softp->ips_sess_list; ((a = *ap) != NULL); ap = &a->aps_next)
1088		if (a == aps) {
1089			*ap = a->aps_next;
1090			break;
1091		}
1092
1093	apr = aps->aps_apr;
1094	if ((apr != NULL) && (apr->apr_del != NULL))
1095		(*apr->apr_del)(softc, aps);
1096
1097	if ((aps->aps_data != NULL) && (aps->aps_psiz != 0))
1098		KFREES(aps->aps_data, aps->aps_psiz);
1099	KFREE(aps);
1100}
1101
1102
1103/* ------------------------------------------------------------------------ */
1104/* Function:    ipf_proxy_fixseqack                                         */
1105/* Returns:     int    - 2 if TCP ack/seq is changed, else 0                */
1106/* Parameters:  fin(I) - pointer to packet information                      */
1107/*              ip(I)  - pointer to IP header                               */
1108/*              nat(I) - pointer to current NAT session                     */
1109/*              inc(I) - delta to apply to TCP sequence numbering           */
1110/*                                                                          */
1111/* Adjust the TCP sequence/acknowledge numbers in the TCP header based on   */
1112/* whether or not the new header is past the point at which an adjustment   */
1113/* occurred. This might happen because of (say) an FTP string being changed */
1114/* and the new string being a different length to the old.                  */
1115/* ------------------------------------------------------------------------ */
1116static int
1117ipf_proxy_fixseqack(fr_info_t *fin, ip_t *ip, ap_session_t *aps, int inc)
1118{
1119	ipf_main_softc_t *softc = fin->fin_main_soft;
1120	ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
1121	int sel, ch = 0, out, nlen;
1122	u_32_t seq1, seq2;
1123	tcphdr_t *tcp;
1124	short inc2;
1125
1126	tcp = (tcphdr_t *)fin->fin_dp;
1127	out = fin->fin_out;
1128	/*
1129	 * ip_len has already been adjusted by 'inc'.
1130	 */
1131	nlen = fin->fin_dlen;
1132	nlen -= (TCP_OFF(tcp) << 2);
1133
1134	inc2 = inc;
1135	inc = (int)inc2;
1136
1137	if (out != 0) {
1138		seq1 = (u_32_t)ntohl(tcp->th_seq);
1139		sel = aps->aps_sel[out];
1140
1141		/* switch to other set ? */
1142		if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) &&
1143		    (seq1 > aps->aps_seqmin[!sel])) {
1144			if (softp->ips_proxy_debug & 0x10)
1145				printf("proxy out switch set seq %d -> %d %x > %x\n",
1146					sel, !sel, seq1,
1147					aps->aps_seqmin[!sel]);
1148			sel = aps->aps_sel[out] = !sel;
1149		}
1150
1151		if (aps->aps_seqoff[sel]) {
1152			seq2 = aps->aps_seqmin[sel] - aps->aps_seqoff[sel];
1153			if (seq1 > seq2) {
1154				seq2 = aps->aps_seqoff[sel];
1155				seq1 += seq2;
1156				tcp->th_seq = htonl(seq1);
1157				ch = 1;
1158			}
1159		}
1160
1161		if (inc && (seq1 > aps->aps_seqmin[!sel])) {
1162			aps->aps_seqmin[sel] = seq1 + nlen - 1;
1163			aps->aps_seqoff[sel] = aps->aps_seqoff[sel] + inc;
1164			if (softp->ips_proxy_debug & 0x10)
1165				printf("proxy seq set %d at %x to %d + %d\n",
1166					sel, aps->aps_seqmin[sel],
1167					aps->aps_seqoff[sel], inc);
1168		}
1169
1170		/***/
1171
1172		seq1 = ntohl(tcp->th_ack);
1173		sel = aps->aps_sel[1 - out];
1174
1175		/* switch to other set ? */
1176		if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) &&
1177		    (seq1 > aps->aps_ackmin[!sel])) {
1178			if (softp->ips_proxy_debug & 0x10)
1179				printf("proxy out switch set ack %d -> %d %x > %x\n",
1180					sel, !sel, seq1,
1181					aps->aps_ackmin[!sel]);
1182			sel = aps->aps_sel[1 - out] = !sel;
1183		}
1184
1185		if (aps->aps_ackoff[sel] && (seq1 > aps->aps_ackmin[sel])) {
1186			seq2 = aps->aps_ackoff[sel];
1187			tcp->th_ack = htonl(seq1 - seq2);
1188			ch = 1;
1189		}
1190	} else {
1191		seq1 = ntohl(tcp->th_seq);
1192		sel = aps->aps_sel[out];
1193
1194		/* switch to other set ? */
1195		if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) &&
1196		    (seq1 > aps->aps_ackmin[!sel])) {
1197			if (softp->ips_proxy_debug & 0x10)
1198				printf("proxy in switch set ack %d -> %d %x > %x\n",
1199					sel, !sel, seq1, aps->aps_ackmin[!sel]);
1200			sel = aps->aps_sel[out] = !sel;
1201		}
1202
1203		if (aps->aps_ackoff[sel]) {
1204			seq2 = aps->aps_ackmin[sel] - aps->aps_ackoff[sel];
1205			if (seq1 > seq2) {
1206				seq2 = aps->aps_ackoff[sel];
1207				seq1 += seq2;
1208				tcp->th_seq = htonl(seq1);
1209				ch = 1;
1210			}
1211		}
1212
1213		if (inc && (seq1 > aps->aps_ackmin[!sel])) {
1214			aps->aps_ackmin[!sel] = seq1 + nlen - 1;
1215			aps->aps_ackoff[!sel] = aps->aps_ackoff[sel] + inc;
1216
1217			if (softp->ips_proxy_debug & 0x10)
1218				printf("proxy ack set %d at %x to %d + %d\n",
1219					!sel, aps->aps_seqmin[!sel],
1220					aps->aps_seqoff[sel], inc);
1221		}
1222
1223		/***/
1224
1225		seq1 = ntohl(tcp->th_ack);
1226		sel = aps->aps_sel[1 - out];
1227
1228		/* switch to other set ? */
1229		if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) &&
1230		    (seq1 > aps->aps_seqmin[!sel])) {
1231			if (softp->ips_proxy_debug & 0x10)
1232				printf("proxy in switch set seq %d -> %d %x > %x\n",
1233					sel, !sel, seq1, aps->aps_seqmin[!sel]);
1234			sel = aps->aps_sel[1 - out] = !sel;
1235		}
1236
1237		if (aps->aps_seqoff[sel] != 0) {
1238			if (softp->ips_proxy_debug & 0x10)
1239				printf("sel %d seqoff %d seq1 %x seqmin %x\n",
1240					sel, aps->aps_seqoff[sel], seq1,
1241					aps->aps_seqmin[sel]);
1242			if (seq1 > aps->aps_seqmin[sel]) {
1243				seq2 = aps->aps_seqoff[sel];
1244				tcp->th_ack = htonl(seq1 - seq2);
1245				ch = 1;
1246			}
1247		}
1248	}
1249
1250	if (softp->ips_proxy_debug & 0x10)
1251		printf("ipf_proxy_fixseqack: seq %u ack %u\n",
1252			(u_32_t)ntohl(tcp->th_seq), (u_32_t)ntohl(tcp->th_ack));
1253	return (ch ? 2 : 0);
1254}
1255
1256
1257/* ------------------------------------------------------------------------ */
1258/* Function:    ipf_proxy_rule_rev                                          */
1259/* Returns:     ipnat_t * - NULL = failure, else pointer to new rule        */
1260/* Parameters:  nat(I) - pointer to NAT session to create rule from         */
1261/*                                                                          */
1262/* This function creates a NAT rule that is based upon the reverse packet   */
1263/* flow associated with this NAT session. Thus if this NAT session was      */
1264/* created with a map rule then this function will create a rdr rule.       */
1265/* Only address fields and network interfaces are assigned in this function */
1266/* and the address fields are formed such that an exact is required. If the */
1267/* original rule had a netmask, that is not replicated here not is it       */
1268/* desired. The ultimate goal here is to create a NAT rule to support a NAT */
1269/* session being created that does not have a user configured rule. The     */
1270/* classic example is supporting the FTP proxy, where a data channel needs  */
1271/* to be setup, based on the addresses used for the control connection. In  */
1272/* that case, this function is used to handle creating NAT rules to support */
1273/* data connections with the PORT and EPRT commands.                        */
1274/* ------------------------------------------------------------------------ */
1275ipnat_t *
1276ipf_proxy_rule_rev(nat_t *nat)
1277{
1278	ipnat_t *old;
1279	ipnat_t *ipn;
1280	int size;
1281
1282	old = nat->nat_ptr;
1283	size = old->in_size;
1284
1285	KMALLOCS(ipn, ipnat_t *, size);
1286	if (ipn == NULL)
1287		return (NULL);
1288
1289	bzero((char *)ipn, size);
1290
1291	ipn->in_use = 1;
1292	ipn->in_hits = 1;
1293	ipn->in_ippip = 1;
1294	ipn->in_apr = NULL;
1295	ipn->in_size = size;
1296	ipn->in_pr[0] = old->in_pr[1];
1297	ipn->in_pr[1] = old->in_pr[0];
1298	ipn->in_v[0] = old->in_v[1];
1299	ipn->in_v[1] = old->in_v[0];
1300	ipn->in_ifps[0] = old->in_ifps[1];
1301	ipn->in_ifps[1] = old->in_ifps[0];
1302	ipn->in_flags = (old->in_flags | IPN_PROXYRULE);
1303
1304	ipn->in_nsrcip6 = nat->nat_odst6;
1305	ipn->in_osrcip6 = nat->nat_ndst6;
1306
1307	if ((old->in_redir & NAT_REDIRECT) != 0) {
1308		ipn->in_redir = NAT_MAP;
1309		if (ipn->in_v[0] == 4) {
1310			ipn->in_snip = ntohl(nat->nat_odstaddr);
1311			ipn->in_dnip = ntohl(nat->nat_nsrcaddr);
1312#ifdef USE_INET6
1313		} else {
1314			ipn->in_snip6 = nat->nat_odst6;
1315			ipn->in_dnip6 = nat->nat_nsrc6;
1316#endif
1317		}
1318		ipn->in_ndstip6 = nat->nat_nsrc6;
1319		ipn->in_odstip6 = nat->nat_osrc6;
1320	} else {
1321		ipn->in_redir = NAT_REDIRECT;
1322		if (ipn->in_v[0] == 4) {
1323			ipn->in_snip = ntohl(nat->nat_odstaddr);
1324			ipn->in_dnip = ntohl(nat->nat_osrcaddr);
1325#ifdef USE_INET6
1326		} else {
1327			ipn->in_snip6 = nat->nat_odst6;
1328			ipn->in_dnip6 = nat->nat_osrc6;
1329#endif
1330		}
1331		ipn->in_ndstip6 = nat->nat_osrc6;
1332		ipn->in_odstip6 = nat->nat_nsrc6;
1333	}
1334
1335	IP6_SETONES(&ipn->in_osrcmsk6);
1336	IP6_SETONES(&ipn->in_nsrcmsk6);
1337	IP6_SETONES(&ipn->in_odstmsk6);
1338	IP6_SETONES(&ipn->in_ndstmsk6);
1339
1340	ipn->in_namelen = old->in_namelen;
1341	ipn->in_ifnames[0] = old->in_ifnames[1];
1342	ipn->in_ifnames[1] = old->in_ifnames[0];
1343	bcopy(old->in_names, ipn->in_names, ipn->in_namelen);
1344	MUTEX_INIT(&ipn->in_lock, "ipnat rev rule lock");
1345
1346	return (ipn);
1347}
1348
1349
1350/* ------------------------------------------------------------------------ */
1351/* Function:    ipf_proxy_rule_fwd                                          */
1352/* Returns:     ipnat_t * - NULL = failure, else pointer to new rule        */
1353/* Parameters:  nat(I) - pointer to NAT session to create rule from         */
1354/*                                                                          */
1355/* The purpose and rationale of this function is much the same as the above */
1356/* function, ipf_proxy_rule_rev, except that a rule is created that matches */
1357/* the same direction as that of the existing NAT session. Thus if this NAT */
1358/* session was created with a map rule then this function will also create  */
1359/* a data structure to represent a map rule. Whereas ipf_proxy_rule_rev is  */
1360/* used to support PORT/EPRT, this function supports PASV/EPSV.             */
1361/* ------------------------------------------------------------------------ */
1362ipnat_t *
1363ipf_proxy_rule_fwd(nat_t *nat)
1364{
1365	ipnat_t *old;
1366	ipnat_t *ipn;
1367	int size;
1368
1369	old = nat->nat_ptr;
1370	size = old->in_size;
1371
1372	KMALLOCS(ipn, ipnat_t *, size);
1373	if (ipn == NULL)
1374		return (NULL);
1375
1376	bzero((char *)ipn, size);
1377
1378	ipn->in_use = 1;
1379	ipn->in_hits = 1;
1380	ipn->in_ippip = 1;
1381	ipn->in_apr = NULL;
1382	ipn->in_size = size;
1383	ipn->in_pr[0] = old->in_pr[0];
1384	ipn->in_pr[1] = old->in_pr[1];
1385	ipn->in_v[0] = old->in_v[0];
1386	ipn->in_v[1] = old->in_v[1];
1387	ipn->in_ifps[0] = nat->nat_ifps[0];
1388	ipn->in_ifps[1] = nat->nat_ifps[1];
1389	ipn->in_flags = (old->in_flags | IPN_PROXYRULE);
1390
1391	ipn->in_nsrcip6 = nat->nat_nsrc6;
1392	ipn->in_osrcip6 = nat->nat_osrc6;
1393	ipn->in_ndstip6 = nat->nat_ndst6;
1394	ipn->in_odstip6 = nat->nat_odst6;
1395	ipn->in_redir = old->in_redir;
1396
1397	if (ipn->in_v[0] == 4) {
1398		ipn->in_snip = ntohl(nat->nat_nsrcaddr);
1399		ipn->in_dnip = ntohl(nat->nat_ndstaddr);
1400#ifdef USE_INET6
1401	} else {
1402		ipn->in_snip6 = nat->nat_nsrc6;
1403		ipn->in_dnip6 = nat->nat_ndst6;
1404#endif
1405	}
1406
1407	IP6_SETONES(&ipn->in_osrcmsk6);
1408	IP6_SETONES(&ipn->in_nsrcmsk6);
1409	IP6_SETONES(&ipn->in_odstmsk6);
1410	IP6_SETONES(&ipn->in_ndstmsk6);
1411
1412	ipn->in_namelen = old->in_namelen;
1413	ipn->in_ifnames[0] = old->in_ifnames[0];
1414	ipn->in_ifnames[1] = old->in_ifnames[1];
1415	bcopy(old->in_names, ipn->in_names, ipn->in_namelen);
1416	MUTEX_INIT(&ipn->in_lock, "ipnat fwd rule lock");
1417
1418	return (ipn);
1419}
1420