1/*	$FreeBSD: releng/10.3/sys/contrib/ipfilter/netinet/ip_fil_freebsd.c 289210 2015-10-13 04:19:49Z cy $	*/
2
3/*
4 * Copyright (C) 2012 by Darren Reed.
5 *
6 * See the IPFILTER.LICENCE file for details on licencing.
7 */
8#if !defined(lint)
9static const char sccsid[] = "@(#)ip_fil.c	2.41 6/5/96 (C) 1993-2000 Darren Reed";
10static const char rcsid[] = "@(#)$Id$";
11#endif
12
13#if defined(KERNEL) || defined(_KERNEL)
14# undef KERNEL
15# undef _KERNEL
16# define	KERNEL	1
17# define	_KERNEL	1
18#endif
19#if defined(__FreeBSD_version) && (__FreeBSD_version >= 400000) && \
20    !defined(KLD_MODULE) && !defined(IPFILTER_LKM)
21# include "opt_inet6.h"
22#endif
23#if defined(__FreeBSD_version) && (__FreeBSD_version >= 440000) && \
24    !defined(KLD_MODULE) && !defined(IPFILTER_LKM)
25# include "opt_random_ip_id.h"
26#endif
27#include <sys/param.h>
28#include <sys/errno.h>
29#include <sys/types.h>
30#include <sys/file.h>
31# include <sys/fcntl.h>
32# include <sys/filio.h>
33#include <sys/time.h>
34#include <sys/systm.h>
35# include <sys/dirent.h>
36#if defined(__FreeBSD_version) && (__FreeBSD_version >= 800000)
37#include <sys/jail.h>
38#endif
39# include <sys/mbuf.h>
40# include <sys/sockopt.h>
41#if !defined(__hpux)
42# include <sys/mbuf.h>
43#endif
44#include <sys/socket.h>
45# include <sys/selinfo.h>
46# include <netinet/tcp_var.h>
47
48#include <net/if.h>
49# include <net/if_var.h>
50#  include <net/netisr.h>
51#include <net/route.h>
52#include <netinet/in.h>
53#include <netinet/in_var.h>
54#include <netinet/in_systm.h>
55#include <netinet/ip.h>
56#include <netinet/ip_var.h>
57#include <netinet/tcp.h>
58#if defined(__FreeBSD_version) && (__FreeBSD_version >= 800000)
59#include <net/vnet.h>
60#else
61#define CURVNET_SET(arg)
62#define CURVNET_RESTORE()
63#endif
64#if defined(__osf__)
65# include <netinet/tcp_timer.h>
66#endif
67#include <netinet/udp.h>
68#include <netinet/tcpip.h>
69#include <netinet/ip_icmp.h>
70#include "netinet/ip_compat.h"
71#ifdef USE_INET6
72# include <netinet/icmp6.h>
73#endif
74#include "netinet/ip_fil.h"
75#include "netinet/ip_nat.h"
76#include "netinet/ip_frag.h"
77#include "netinet/ip_state.h"
78#include "netinet/ip_proxy.h"
79#include "netinet/ip_auth.h"
80#include "netinet/ip_sync.h"
81#include "netinet/ip_lookup.h"
82#include "netinet/ip_dstlist.h"
83#ifdef	IPFILTER_SCAN
84#include "netinet/ip_scan.h"
85#endif
86#include "netinet/ip_pool.h"
87# include <sys/malloc.h>
88#include <sys/kernel.h>
89#ifdef CSUM_DATA_VALID
90#include <machine/in_cksum.h>
91#endif
92extern	int	ip_optcopy __P((struct ip *, struct ip *));
93
94
95# ifdef IPFILTER_M_IPFILTER
96MALLOC_DEFINE(M_IPFILTER, "ipfilter", "IP Filter packet filter data structures");
97# endif
98
99
100static	u_short	ipid = 0;
101static	int	(*ipf_savep) __P((void *, ip_t *, int, void *, int, struct mbuf **));
102static	int	ipf_send_ip __P((fr_info_t *, mb_t *));
103static void	ipf_timer_func __P((void *arg));
104int		ipf_locks_done = 0;
105
106ipf_main_softc_t ipfmain;
107
108# include <sys/conf.h>
109# if defined(NETBSD_PF)
110#  include <net/pfil.h>
111# endif /* NETBSD_PF */
112/*
113 * We provide the ipf_checkp name just to minimize changes later.
114 */
115int (*ipf_checkp) __P((void *, ip_t *ip, int hlen, void *ifp, int out, mb_t **mp));
116
117
118static eventhandler_tag ipf_arrivetag, ipf_departtag, ipf_clonetag;
119
120static void ipf_ifevent(void *arg);
121
122static void ipf_ifevent(arg)
123	void *arg;
124{
125        ipf_sync(arg, NULL);
126}
127
128
129
130static int
131ipf_check_wrapper(void *arg, struct mbuf **mp, struct ifnet *ifp, int dir)
132{
133	struct ip *ip = mtod(*mp, struct ip *);
134	int rv;
135
136	/*
137	 * IPFilter expects evreything in network byte order
138	 */
139#if (__FreeBSD_version < 1000019)
140	ip->ip_len = htons(ip->ip_len);
141	ip->ip_off = htons(ip->ip_off);
142#endif
143	rv = ipf_check(&ipfmain, ip, ip->ip_hl << 2, ifp, (dir == PFIL_OUT),
144		       mp);
145#if (__FreeBSD_version < 1000019)
146	if ((rv == 0) && (*mp != NULL)) {
147		ip = mtod(*mp, struct ip *);
148		ip->ip_len = ntohs(ip->ip_len);
149		ip->ip_off = ntohs(ip->ip_off);
150	}
151#endif
152	return rv;
153}
154
155# ifdef USE_INET6
156#  include <netinet/ip6.h>
157
158static int
159ipf_check_wrapper6(void *arg, struct mbuf **mp, struct ifnet *ifp, int dir)
160{
161	return (ipf_check(&ipfmain, mtod(*mp, struct ip *),
162			  sizeof(struct ip6_hdr), ifp, (dir == PFIL_OUT), mp));
163}
164# endif
165#if	defined(IPFILTER_LKM)
166int ipf_identify(s)
167	char *s;
168{
169	if (strcmp(s, "ipl") == 0)
170		return 1;
171	return 0;
172}
173#endif /* IPFILTER_LKM */
174
175
176static void
177ipf_timer_func(arg)
178	void *arg;
179{
180	ipf_main_softc_t *softc = arg;
181	SPL_INT(s);
182
183	SPL_NET(s);
184	READ_ENTER(&softc->ipf_global);
185
186        if (softc->ipf_running > 0)
187		ipf_slowtimer(softc);
188
189	if (softc->ipf_running == -1 || softc->ipf_running == 1) {
190#if 0
191		softc->ipf_slow_ch = timeout(ipf_timer_func, softc, hz/2);
192#endif
193		callout_init(&softc->ipf_slow_ch, CALLOUT_MPSAFE);
194		callout_reset(&softc->ipf_slow_ch,
195			(hz / IPF_HZ_DIVIDE) * IPF_HZ_MULT,
196			ipf_timer_func, softc);
197	}
198	RWLOCK_EXIT(&softc->ipf_global);
199	SPL_X(s);
200}
201
202
203int
204ipfattach(softc)
205	ipf_main_softc_t *softc;
206{
207#ifdef USE_SPL
208	int s;
209#endif
210
211	SPL_NET(s);
212	if (softc->ipf_running > 0) {
213		SPL_X(s);
214		return EBUSY;
215	}
216
217	if (ipf_init_all(softc) < 0) {
218		SPL_X(s);
219		return EIO;
220	}
221
222
223	if (ipf_checkp != ipf_check) {
224		ipf_savep = ipf_checkp;
225		ipf_checkp = ipf_check;
226	}
227
228	bzero((char *)ipfmain.ipf_selwait, sizeof(ipfmain.ipf_selwait));
229	softc->ipf_running = 1;
230
231	if (softc->ipf_control_forwarding & 1)
232		V_ipforwarding = 1;
233
234	ipid = 0;
235
236	SPL_X(s);
237#if 0
238	softc->ipf_slow_ch = timeout(ipf_timer_func, softc,
239				     (hz / IPF_HZ_DIVIDE) * IPF_HZ_MULT);
240#endif
241	callout_init(&softc->ipf_slow_ch, CALLOUT_MPSAFE);
242	callout_reset(&softc->ipf_slow_ch, (hz / IPF_HZ_DIVIDE) * IPF_HZ_MULT,
243		ipf_timer_func, softc);
244	return 0;
245}
246
247
248/*
249 * Disable the filter by removing the hooks from the IP input/output
250 * stream.
251 */
252int
253ipfdetach(softc)
254	ipf_main_softc_t *softc;
255{
256#ifdef USE_SPL
257	int s;
258#endif
259
260	if (softc->ipf_control_forwarding & 2)
261		V_ipforwarding = 0;
262
263	SPL_NET(s);
264
265#if 0
266	if (softc->ipf_slow_ch.callout != NULL)
267		untimeout(ipf_timer_func, softc, softc->ipf_slow_ch);
268	bzero(&softc->ipf_slow, sizeof(softc->ipf_slow));
269#endif
270	callout_drain(&softc->ipf_slow_ch);
271
272#ifndef NETBSD_PF
273	if (ipf_checkp != NULL)
274		ipf_checkp = ipf_savep;
275	ipf_savep = NULL;
276#endif
277
278	ipf_fini_all(softc);
279
280	softc->ipf_running = -2;
281
282	SPL_X(s);
283
284	return 0;
285}
286
287
288/*
289 * Filter ioctl interface.
290 */
291int
292ipfioctl(dev, cmd, data, mode
293, p)
294	struct thread *p;
295#    define	p_cred	td_ucred
296#    define	p_uid	td_ucred->cr_ruid
297	struct cdev *dev;
298	ioctlcmd_t cmd;
299	caddr_t data;
300	int mode;
301{
302	int error = 0, unit = 0;
303	SPL_INT(s);
304
305#if (BSD >= 199306)
306        if (securelevel_ge(p->p_cred, 3) && (mode & FWRITE))
307	{
308		ipfmain.ipf_interror = 130001;
309		return EPERM;
310	}
311#endif
312
313	unit = GET_MINOR(dev);
314	if ((IPL_LOGMAX < unit) || (unit < 0)) {
315		ipfmain.ipf_interror = 130002;
316		return ENXIO;
317	}
318
319	if (ipfmain.ipf_running <= 0) {
320		if (unit != IPL_LOGIPF && cmd != SIOCIPFINTERROR) {
321			ipfmain.ipf_interror = 130003;
322			return EIO;
323		}
324		if (cmd != SIOCIPFGETNEXT && cmd != SIOCIPFGET &&
325		    cmd != SIOCIPFSET && cmd != SIOCFRENB &&
326		    cmd != SIOCGETFS && cmd != SIOCGETFF &&
327		    cmd != SIOCIPFINTERROR) {
328			ipfmain.ipf_interror = 130004;
329			return EIO;
330		}
331	}
332
333	SPL_NET(s);
334
335	CURVNET_SET(TD_TO_VNET(p));
336	error = ipf_ioctlswitch(&ipfmain, unit, data, cmd, mode, p->p_uid, p);
337	CURVNET_RESTORE();
338	if (error != -1) {
339		SPL_X(s);
340		return error;
341	}
342
343	SPL_X(s);
344
345	return error;
346}
347
348
349/*
350 * ipf_send_reset - this could conceivably be a call to tcp_respond(), but that
351 * requires a large amount of setting up and isn't any more efficient.
352 */
353int
354ipf_send_reset(fin)
355	fr_info_t *fin;
356{
357	struct tcphdr *tcp, *tcp2;
358	int tlen = 0, hlen;
359	struct mbuf *m;
360#ifdef USE_INET6
361	ip6_t *ip6;
362#endif
363	ip_t *ip;
364
365	tcp = fin->fin_dp;
366	if (tcp->th_flags & TH_RST)
367		return -1;		/* feedback loop */
368
369	if (ipf_checkl4sum(fin) == -1)
370		return -1;
371
372	tlen = fin->fin_dlen - (TCP_OFF(tcp) << 2) +
373			((tcp->th_flags & TH_SYN) ? 1 : 0) +
374			((tcp->th_flags & TH_FIN) ? 1 : 0);
375
376#ifdef USE_INET6
377	hlen = (fin->fin_v == 6) ? sizeof(ip6_t) : sizeof(ip_t);
378#else
379	hlen = sizeof(ip_t);
380#endif
381#ifdef MGETHDR
382	MGETHDR(m, M_DONTWAIT, MT_HEADER);
383#else
384	MGET(m, M_DONTWAIT, MT_HEADER);
385#endif
386	if (m == NULL)
387		return -1;
388	if (sizeof(*tcp2) + hlen > MLEN) {
389		MCLGET(m, M_DONTWAIT);
390		if ((m->m_flags & M_EXT) == 0) {
391			FREE_MB_T(m);
392			return -1;
393		}
394	}
395
396	m->m_len = sizeof(*tcp2) + hlen;
397#if (BSD >= 199103)
398	m->m_data += max_linkhdr;
399	m->m_pkthdr.len = m->m_len;
400	m->m_pkthdr.rcvif = (struct ifnet *)0;
401#endif
402	ip = mtod(m, struct ip *);
403	bzero((char *)ip, hlen);
404#ifdef USE_INET6
405	ip6 = (ip6_t *)ip;
406#endif
407	tcp2 = (struct tcphdr *)((char *)ip + hlen);
408	tcp2->th_sport = tcp->th_dport;
409	tcp2->th_dport = tcp->th_sport;
410
411	if (tcp->th_flags & TH_ACK) {
412		tcp2->th_seq = tcp->th_ack;
413		tcp2->th_flags = TH_RST;
414		tcp2->th_ack = 0;
415	} else {
416		tcp2->th_seq = 0;
417		tcp2->th_ack = ntohl(tcp->th_seq);
418		tcp2->th_ack += tlen;
419		tcp2->th_ack = htonl(tcp2->th_ack);
420		tcp2->th_flags = TH_RST|TH_ACK;
421	}
422	TCP_X2_A(tcp2, 0);
423	TCP_OFF_A(tcp2, sizeof(*tcp2) >> 2);
424	tcp2->th_win = tcp->th_win;
425	tcp2->th_sum = 0;
426	tcp2->th_urp = 0;
427
428#ifdef USE_INET6
429	if (fin->fin_v == 6) {
430		ip6->ip6_flow = ((ip6_t *)fin->fin_ip)->ip6_flow;
431		ip6->ip6_plen = htons(sizeof(struct tcphdr));
432		ip6->ip6_nxt = IPPROTO_TCP;
433		ip6->ip6_hlim = 0;
434		ip6->ip6_src = fin->fin_dst6.in6;
435		ip6->ip6_dst = fin->fin_src6.in6;
436		tcp2->th_sum = in6_cksum(m, IPPROTO_TCP,
437					 sizeof(*ip6), sizeof(*tcp2));
438		return ipf_send_ip(fin, m);
439	}
440#endif
441	ip->ip_p = IPPROTO_TCP;
442	ip->ip_len = htons(sizeof(struct tcphdr));
443	ip->ip_src.s_addr = fin->fin_daddr;
444	ip->ip_dst.s_addr = fin->fin_saddr;
445	tcp2->th_sum = in_cksum(m, hlen + sizeof(*tcp2));
446	ip->ip_len = htons(hlen + sizeof(*tcp2));
447	return ipf_send_ip(fin, m);
448}
449
450
451/*
452 * ip_len must be in network byte order when called.
453 */
454static int
455ipf_send_ip(fin, m)
456	fr_info_t *fin;
457	mb_t *m;
458{
459	fr_info_t fnew;
460	ip_t *ip, *oip;
461	int hlen;
462
463	ip = mtod(m, ip_t *);
464	bzero((char *)&fnew, sizeof(fnew));
465	fnew.fin_main_soft = fin->fin_main_soft;
466
467	IP_V_A(ip, fin->fin_v);
468	switch (fin->fin_v)
469	{
470	case 4 :
471		oip = fin->fin_ip;
472		hlen = sizeof(*oip);
473		fnew.fin_v = 4;
474		fnew.fin_p = ip->ip_p;
475		fnew.fin_plen = ntohs(ip->ip_len);
476		IP_HL_A(ip, sizeof(*oip) >> 2);
477		ip->ip_tos = oip->ip_tos;
478		ip->ip_id = fin->fin_ip->ip_id;
479#if defined(FreeBSD) && (__FreeBSD_version > 460000)
480		ip->ip_off = htons(path_mtu_discovery ? IP_DF : 0);
481#else
482		ip->ip_off = 0;
483#endif
484		ip->ip_ttl = V_ip_defttl;
485		ip->ip_sum = 0;
486		break;
487#ifdef USE_INET6
488	case 6 :
489	{
490		ip6_t *ip6 = (ip6_t *)ip;
491
492		ip6->ip6_vfc = 0x60;
493		ip6->ip6_hlim = IPDEFTTL;
494
495		hlen = sizeof(*ip6);
496		fnew.fin_p = ip6->ip6_nxt;
497		fnew.fin_v = 6;
498		fnew.fin_plen = ntohs(ip6->ip6_plen) + hlen;
499		break;
500	}
501#endif
502	default :
503		return EINVAL;
504	}
505#ifdef IPSEC
506	m->m_pkthdr.rcvif = NULL;
507#endif
508
509	fnew.fin_ifp = fin->fin_ifp;
510	fnew.fin_flx = FI_NOCKSUM;
511	fnew.fin_m = m;
512	fnew.fin_ip = ip;
513	fnew.fin_mp = &m;
514	fnew.fin_hlen = hlen;
515	fnew.fin_dp = (char *)ip + hlen;
516	(void) ipf_makefrip(hlen, ip, &fnew);
517
518	return ipf_fastroute(m, &m, &fnew, NULL);
519}
520
521
522int
523ipf_send_icmp_err(type, fin, dst)
524	int type;
525	fr_info_t *fin;
526	int dst;
527{
528	int err, hlen, xtra, iclen, ohlen, avail, code;
529	struct in_addr dst4;
530	struct icmp *icmp;
531	struct mbuf *m;
532	i6addr_t dst6;
533	void *ifp;
534#ifdef USE_INET6
535	ip6_t *ip6;
536#endif
537	ip_t *ip, *ip2;
538
539	if ((type < 0) || (type >= ICMP_MAXTYPE))
540		return -1;
541
542	code = fin->fin_icode;
543#ifdef USE_INET6
544#if 0
545	/* XXX Fix an off by one error: s/>/>=/
546	 was:
547	 if ((code < 0) || (code > sizeof(icmptoicmp6unreach)/sizeof(int)))
548	 Fix obtained from NetBSD ip_fil_netbsd.c r1.4: */
549#endif
550	if ((code < 0) || (code >= sizeof(icmptoicmp6unreach)/sizeof(int)))
551		return -1;
552#endif
553
554	if (ipf_checkl4sum(fin) == -1)
555		return -1;
556#ifdef MGETHDR
557	MGETHDR(m, M_DONTWAIT, MT_HEADER);
558#else
559	MGET(m, M_DONTWAIT, MT_HEADER);
560#endif
561	if (m == NULL)
562		return -1;
563	avail = MHLEN;
564
565	xtra = 0;
566	hlen = 0;
567	ohlen = 0;
568	dst4.s_addr = 0;
569	ifp = fin->fin_ifp;
570	if (fin->fin_v == 4) {
571		if ((fin->fin_p == IPPROTO_ICMP) && !(fin->fin_flx & FI_SHORT))
572			switch (ntohs(fin->fin_data[0]) >> 8)
573			{
574			case ICMP_ECHO :
575			case ICMP_TSTAMP :
576			case ICMP_IREQ :
577			case ICMP_MASKREQ :
578				break;
579			default :
580				FREE_MB_T(m);
581				return 0;
582			}
583
584		if (dst == 0) {
585			if (ipf_ifpaddr(&ipfmain, 4, FRI_NORMAL, ifp,
586					&dst6, NULL) == -1) {
587				FREE_MB_T(m);
588				return -1;
589			}
590			dst4 = dst6.in4;
591		} else
592			dst4.s_addr = fin->fin_daddr;
593
594		hlen = sizeof(ip_t);
595		ohlen = fin->fin_hlen;
596		iclen = hlen + offsetof(struct icmp, icmp_ip) + ohlen;
597		if (fin->fin_hlen < fin->fin_plen)
598			xtra = MIN(fin->fin_dlen, 8);
599		else
600			xtra = 0;
601	}
602
603#ifdef USE_INET6
604	else if (fin->fin_v == 6) {
605		hlen = sizeof(ip6_t);
606		ohlen = sizeof(ip6_t);
607		iclen = hlen + offsetof(struct icmp, icmp_ip) + ohlen;
608		type = icmptoicmp6types[type];
609		if (type == ICMP6_DST_UNREACH)
610			code = icmptoicmp6unreach[code];
611
612		if (iclen + max_linkhdr + fin->fin_plen > avail) {
613			MCLGET(m, M_DONTWAIT);
614			if ((m->m_flags & M_EXT) == 0) {
615				FREE_MB_T(m);
616				return -1;
617			}
618			avail = MCLBYTES;
619		}
620		xtra = MIN(fin->fin_plen, avail - iclen - max_linkhdr);
621		xtra = MIN(xtra, IPV6_MMTU - iclen);
622		if (dst == 0) {
623			if (ipf_ifpaddr(&ipfmain, 6, FRI_NORMAL, ifp,
624					&dst6, NULL) == -1) {
625				FREE_MB_T(m);
626				return -1;
627			}
628		} else
629			dst6 = fin->fin_dst6;
630	}
631#endif
632	else {
633		FREE_MB_T(m);
634		return -1;
635	}
636
637	avail -= (max_linkhdr + iclen);
638	if (avail < 0) {
639		FREE_MB_T(m);
640		return -1;
641	}
642	if (xtra > avail)
643		xtra = avail;
644	iclen += xtra;
645	m->m_data += max_linkhdr;
646	m->m_pkthdr.rcvif = (struct ifnet *)0;
647	m->m_pkthdr.len = iclen;
648	m->m_len = iclen;
649	ip = mtod(m, ip_t *);
650	icmp = (struct icmp *)((char *)ip + hlen);
651	ip2 = (ip_t *)&icmp->icmp_ip;
652
653	icmp->icmp_type = type;
654	icmp->icmp_code = fin->fin_icode;
655	icmp->icmp_cksum = 0;
656#ifdef icmp_nextmtu
657	if (type == ICMP_UNREACH && fin->fin_icode == ICMP_UNREACH_NEEDFRAG) {
658		if (fin->fin_mtu != 0) {
659			icmp->icmp_nextmtu = htons(fin->fin_mtu);
660
661		} else if (ifp != NULL) {
662			icmp->icmp_nextmtu = htons(GETIFMTU_4(ifp));
663
664		} else {	/* make up a number... */
665			icmp->icmp_nextmtu = htons(fin->fin_plen - 20);
666		}
667	}
668#endif
669
670	bcopy((char *)fin->fin_ip, (char *)ip2, ohlen);
671
672#ifdef USE_INET6
673	ip6 = (ip6_t *)ip;
674	if (fin->fin_v == 6) {
675		ip6->ip6_flow = ((ip6_t *)fin->fin_ip)->ip6_flow;
676		ip6->ip6_plen = htons(iclen - hlen);
677		ip6->ip6_nxt = IPPROTO_ICMPV6;
678		ip6->ip6_hlim = 0;
679		ip6->ip6_src = dst6.in6;
680		ip6->ip6_dst = fin->fin_src6.in6;
681		if (xtra > 0)
682			bcopy((char *)fin->fin_ip + ohlen,
683			      (char *)&icmp->icmp_ip + ohlen, xtra);
684		icmp->icmp_cksum = in6_cksum(m, IPPROTO_ICMPV6,
685					     sizeof(*ip6), iclen - hlen);
686	} else
687#endif
688	{
689		ip->ip_p = IPPROTO_ICMP;
690		ip->ip_src.s_addr = dst4.s_addr;
691		ip->ip_dst.s_addr = fin->fin_saddr;
692
693		if (xtra > 0)
694			bcopy((char *)fin->fin_ip + ohlen,
695			      (char *)&icmp->icmp_ip + ohlen, xtra);
696		icmp->icmp_cksum = ipf_cksum((u_short *)icmp,
697					     sizeof(*icmp) + 8);
698		ip->ip_len = htons(iclen);
699		ip->ip_p = IPPROTO_ICMP;
700	}
701	err = ipf_send_ip(fin, m);
702	return err;
703}
704
705
706
707
708/*
709 * m0 - pointer to mbuf where the IP packet starts
710 * mpp - pointer to the mbuf pointer that is the start of the mbuf chain
711 */
712int
713ipf_fastroute(m0, mpp, fin, fdp)
714	mb_t *m0, **mpp;
715	fr_info_t *fin;
716	frdest_t *fdp;
717{
718	register struct ip *ip, *mhip;
719	register struct mbuf *m = *mpp;
720	register struct route *ro;
721	int len, off, error = 0, hlen, code;
722	struct ifnet *ifp, *sifp;
723	struct sockaddr_in *dst;
724	struct route iproute;
725	u_short ip_off;
726	frdest_t node;
727	frentry_t *fr;
728
729	ro = NULL;
730
731#ifdef M_WRITABLE
732	/*
733	* HOT FIX/KLUDGE:
734	*
735	* If the mbuf we're about to send is not writable (because of
736	* a cluster reference, for example) we'll need to make a copy
737	* of it since this routine modifies the contents.
738	*
739	* If you have non-crappy network hardware that can transmit data
740	* from the mbuf, rather than making a copy, this is gonna be a
741	* problem.
742	*/
743	if (M_WRITABLE(m) == 0) {
744		m0 = m_dup(m, M_DONTWAIT);
745		if (m0 != 0) {
746			FREE_MB_T(m);
747			m = m0;
748			*mpp = m;
749		} else {
750			error = ENOBUFS;
751			FREE_MB_T(m);
752			goto done;
753		}
754	}
755#endif
756
757#ifdef USE_INET6
758	if (fin->fin_v == 6) {
759		/*
760		 * currently "to <if>" and "to <if>:ip#" are not supported
761		 * for IPv6
762		 */
763		return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
764	}
765#endif
766
767	hlen = fin->fin_hlen;
768	ip = mtod(m0, struct ip *);
769	ifp = NULL;
770
771	/*
772	 * Route packet.
773	 */
774	ro = &iproute;
775	bzero(ro, sizeof (*ro));
776	dst = (struct sockaddr_in *)&ro->ro_dst;
777	dst->sin_family = AF_INET;
778	dst->sin_addr = ip->ip_dst;
779
780	fr = fin->fin_fr;
781	if ((fr != NULL) && !(fr->fr_flags & FR_KEEPSTATE) && (fdp != NULL) &&
782	    (fdp->fd_type == FRD_DSTLIST)) {
783		if (ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL, &node) == 0)
784			fdp = &node;
785	}
786
787	if (fdp != NULL)
788		ifp = fdp->fd_ptr;
789	else
790		ifp = fin->fin_ifp;
791
792	if ((ifp == NULL) && ((fr == NULL) || !(fr->fr_flags & FR_FASTROUTE))) {
793		error = -2;
794		goto bad;
795	}
796
797	if ((fdp != NULL) && (fdp->fd_ip.s_addr != 0))
798		dst->sin_addr = fdp->fd_ip;
799
800	dst->sin_len = sizeof(*dst);
801	in_rtalloc(ro, M_GETFIB(m0));
802
803	if ((ifp == NULL) && (ro->ro_rt != NULL))
804		ifp = ro->ro_rt->rt_ifp;
805
806	if ((ro->ro_rt == NULL) || (ifp == NULL)) {
807		if (in_localaddr(ip->ip_dst))
808			error = EHOSTUNREACH;
809		else
810			error = ENETUNREACH;
811		goto bad;
812	}
813	if (ro->ro_rt->rt_flags & RTF_GATEWAY)
814		dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
815	if (ro->ro_rt)
816		counter_u64_add(ro->ro_rt->rt_pksent, 1);
817
818	/*
819	 * For input packets which are being "fastrouted", they won't
820	 * go back through output filtering and miss their chance to get
821	 * NAT'd and counted.  Duplicated packets aren't considered to be
822	 * part of the normal packet stream, so do not NAT them or pass
823	 * them through stateful checking, etc.
824	 */
825	if ((fdp != &fr->fr_dif) && (fin->fin_out == 0)) {
826		sifp = fin->fin_ifp;
827		fin->fin_ifp = ifp;
828		fin->fin_out = 1;
829		(void) ipf_acctpkt(fin, NULL);
830		fin->fin_fr = NULL;
831		if (!fr || !(fr->fr_flags & FR_RETMASK)) {
832			u_32_t pass;
833
834			(void) ipf_state_check(fin, &pass);
835		}
836
837		switch (ipf_nat_checkout(fin, NULL))
838		{
839		case 0 :
840			break;
841		case 1 :
842			ip->ip_sum = 0;
843			break;
844		case -1 :
845			error = -1;
846			goto bad;
847			break;
848		}
849
850		fin->fin_ifp = sifp;
851		fin->fin_out = 0;
852	} else
853		ip->ip_sum = 0;
854	/*
855	 * If small enough for interface, can just send directly.
856	 */
857	if (ntohs(ip->ip_len) <= ifp->if_mtu) {
858		if (!ip->ip_sum)
859			ip->ip_sum = in_cksum(m, hlen);
860		error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst,
861			    ro
862			);
863		goto done;
864	}
865	/*
866	 * Too large for interface; fragment if possible.
867	 * Must be able to put at least 8 bytes per fragment.
868	 */
869	ip_off = ntohs(ip->ip_off);
870	if (ip_off & IP_DF) {
871		error = EMSGSIZE;
872		goto bad;
873	}
874	len = (ifp->if_mtu - hlen) &~ 7;
875	if (len < 8) {
876		error = EMSGSIZE;
877		goto bad;
878	}
879
880    {
881	int mhlen, firstlen = len;
882	struct mbuf **mnext = &m->m_act;
883
884	/*
885	 * Loop through length of segment after first fragment,
886	 * make new header and copy data of each part and link onto chain.
887	 */
888	m0 = m;
889	mhlen = sizeof (struct ip);
890	for (off = hlen + len; off < ntohs(ip->ip_len); off += len) {
891#ifdef MGETHDR
892		MGETHDR(m, M_DONTWAIT, MT_HEADER);
893#else
894		MGET(m, M_DONTWAIT, MT_HEADER);
895#endif
896		if (m == 0) {
897			m = m0;
898			error = ENOBUFS;
899			goto bad;
900		}
901		m->m_data += max_linkhdr;
902		mhip = mtod(m, struct ip *);
903		bcopy((char *)ip, (char *)mhip, sizeof(*ip));
904		if (hlen > sizeof (struct ip)) {
905			mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
906			IP_HL_A(mhip, mhlen >> 2);
907		}
908		m->m_len = mhlen;
909		mhip->ip_off = ((off - hlen) >> 3) + ip_off;
910		if (off + len >= ntohs(ip->ip_len))
911			len = ntohs(ip->ip_len) - off;
912		else
913			mhip->ip_off |= IP_MF;
914		mhip->ip_len = htons((u_short)(len + mhlen));
915		*mnext = m;
916		m->m_next = m_copy(m0, off, len);
917		if (m->m_next == 0) {
918			error = ENOBUFS;	/* ??? */
919			goto sendorfree;
920		}
921		m->m_pkthdr.len = mhlen + len;
922		m->m_pkthdr.rcvif = NULL;
923		mhip->ip_off = htons((u_short)mhip->ip_off);
924		mhip->ip_sum = 0;
925		mhip->ip_sum = in_cksum(m, mhlen);
926		mnext = &m->m_act;
927	}
928	/*
929	 * Update first fragment by trimming what's been copied out
930	 * and updating header, then send each fragment (in order).
931	 */
932	m_adj(m0, hlen + firstlen - ip->ip_len);
933	ip->ip_len = htons((u_short)(hlen + firstlen));
934	ip->ip_off = htons((u_short)IP_MF);
935	ip->ip_sum = 0;
936	ip->ip_sum = in_cksum(m0, hlen);
937sendorfree:
938	for (m = m0; m; m = m0) {
939		m0 = m->m_act;
940		m->m_act = 0;
941		if (error == 0)
942			error = (*ifp->if_output)(ifp, m,
943			    (struct sockaddr *)dst,
944			    ro
945			    );
946		else
947			FREE_MB_T(m);
948	}
949    }
950done:
951	if (!error)
952		ipfmain.ipf_frouteok[0]++;
953	else
954		ipfmain.ipf_frouteok[1]++;
955
956	if ((ro != NULL) && (ro->ro_rt != NULL)) {
957		RTFREE(ro->ro_rt);
958	}
959	return 0;
960bad:
961	if (error == EMSGSIZE) {
962		sifp = fin->fin_ifp;
963		code = fin->fin_icode;
964		fin->fin_icode = ICMP_UNREACH_NEEDFRAG;
965		fin->fin_ifp = ifp;
966		(void) ipf_send_icmp_err(ICMP_UNREACH, fin, 1);
967		fin->fin_ifp = sifp;
968		fin->fin_icode = code;
969	}
970	FREE_MB_T(m);
971	goto done;
972}
973
974
975int
976ipf_verifysrc(fin)
977	fr_info_t *fin;
978{
979	struct sockaddr_in *dst;
980	struct route iproute;
981
982	bzero((char *)&iproute, sizeof(iproute));
983	dst = (struct sockaddr_in *)&iproute.ro_dst;
984	dst->sin_len = sizeof(*dst);
985	dst->sin_family = AF_INET;
986	dst->sin_addr = fin->fin_src;
987	in_rtalloc(&iproute, 0);
988	if (iproute.ro_rt == NULL)
989		return 0;
990	return (fin->fin_ifp == iproute.ro_rt->rt_ifp);
991}
992
993
994/*
995 * return the first IP Address associated with an interface
996 */
997int
998ipf_ifpaddr(softc, v, atype, ifptr, inp, inpmask)
999	ipf_main_softc_t *softc;
1000	int v, atype;
1001	void *ifptr;
1002	i6addr_t *inp, *inpmask;
1003{
1004#ifdef USE_INET6
1005	struct in6_addr *inp6 = NULL;
1006#endif
1007	struct sockaddr *sock, *mask;
1008	struct sockaddr_in *sin;
1009	struct ifaddr *ifa;
1010	struct ifnet *ifp;
1011
1012	if ((ifptr == NULL) || (ifptr == (void *)-1))
1013		return -1;
1014
1015	sin = NULL;
1016	ifp = ifptr;
1017
1018	if (v == 4)
1019		inp->in4.s_addr = 0;
1020#ifdef USE_INET6
1021	else if (v == 6)
1022		bzero((char *)inp, sizeof(*inp));
1023#endif
1024	ifa = TAILQ_FIRST(&ifp->if_addrhead);
1025
1026	sock = ifa->ifa_addr;
1027	while (sock != NULL && ifa != NULL) {
1028		sin = (struct sockaddr_in *)sock;
1029		if ((v == 4) && (sin->sin_family == AF_INET))
1030			break;
1031#ifdef USE_INET6
1032		if ((v == 6) && (sin->sin_family == AF_INET6)) {
1033			inp6 = &((struct sockaddr_in6 *)sin)->sin6_addr;
1034			if (!IN6_IS_ADDR_LINKLOCAL(inp6) &&
1035			    !IN6_IS_ADDR_LOOPBACK(inp6))
1036				break;
1037		}
1038#endif
1039		ifa = TAILQ_NEXT(ifa, ifa_link);
1040		if (ifa != NULL)
1041			sock = ifa->ifa_addr;
1042	}
1043
1044	if (ifa == NULL || sin == NULL)
1045		return -1;
1046
1047	mask = ifa->ifa_netmask;
1048	if (atype == FRI_BROADCAST)
1049		sock = ifa->ifa_broadaddr;
1050	else if (atype == FRI_PEERADDR)
1051		sock = ifa->ifa_dstaddr;
1052
1053	if (sock == NULL)
1054		return -1;
1055
1056#ifdef USE_INET6
1057	if (v == 6) {
1058		return ipf_ifpfillv6addr(atype, (struct sockaddr_in6 *)sock,
1059					 (struct sockaddr_in6 *)mask,
1060					 inp, inpmask);
1061	}
1062#endif
1063	return ipf_ifpfillv4addr(atype, (struct sockaddr_in *)sock,
1064				 (struct sockaddr_in *)mask,
1065				 &inp->in4, &inpmask->in4);
1066}
1067
1068
1069u_32_t
1070ipf_newisn(fin)
1071	fr_info_t *fin;
1072{
1073	u_32_t newiss;
1074	newiss = arc4random();
1075	return newiss;
1076}
1077
1078
1079/* ------------------------------------------------------------------------ */
1080/* Function:    ipf_nextipid                                                */
1081/* Returns:     int - 0 == success, -1 == error (packet should be droppped) */
1082/* Parameters:  fin(I) - pointer to packet information                      */
1083/*                                                                          */
1084/* Returns the next IPv4 ID to use for this packet.                         */
1085/* ------------------------------------------------------------------------ */
1086u_short
1087ipf_nextipid(fin)
1088	fr_info_t *fin;
1089{
1090	u_short id;
1091
1092#ifndef	RANDOM_IP_ID
1093	MUTEX_ENTER(&ipfmain.ipf_rw);
1094	id = ipid++;
1095	MUTEX_EXIT(&ipfmain.ipf_rw);
1096#else
1097	id = ip_randomid();
1098#endif
1099
1100	return id;
1101}
1102
1103
1104INLINE int
1105ipf_checkv4sum(fin)
1106	fr_info_t *fin;
1107{
1108#ifdef CSUM_DATA_VALID
1109	int manual = 0;
1110	u_short sum;
1111	ip_t *ip;
1112	mb_t *m;
1113
1114	if ((fin->fin_flx & FI_NOCKSUM) != 0)
1115		return 0;
1116
1117	if ((fin->fin_flx & FI_SHORT) != 0)
1118		return 1;
1119
1120	if (fin->fin_cksum != FI_CK_NEEDED)
1121		return (fin->fin_cksum > FI_CK_NEEDED) ? 0 : -1;
1122
1123	m = fin->fin_m;
1124	if (m == NULL) {
1125		manual = 1;
1126		goto skipauto;
1127	}
1128	ip = fin->fin_ip;
1129
1130	if ((m->m_pkthdr.csum_flags & (CSUM_IP_CHECKED|CSUM_IP_VALID)) ==
1131	    CSUM_IP_CHECKED) {
1132		fin->fin_cksum = FI_CK_BAD;
1133		fin->fin_flx |= FI_BAD;
1134		return -1;
1135	}
1136	if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
1137		/* Depending on the driver, UDP may have zero checksum */
1138		if (fin->fin_p == IPPROTO_UDP && (fin->fin_flx &
1139		    (FI_FRAG|FI_SHORT|FI_BAD)) == 0) {
1140			udphdr_t *udp = fin->fin_dp;
1141			if (udp->uh_sum == 0) {
1142				/*
1143				 * we're good no matter what the hardware
1144				 * checksum flags and csum_data say (handling
1145				 * of csum_data for zero UDP checksum is not
1146				 * consistent across all drivers)
1147				 */
1148				fin->fin_cksum = 1;
1149				return 0;
1150			}
1151		}
1152
1153		if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
1154			sum = m->m_pkthdr.csum_data;
1155		else
1156			sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
1157					htonl(m->m_pkthdr.csum_data +
1158					fin->fin_dlen + fin->fin_p));
1159		sum ^= 0xffff;
1160		if (sum != 0) {
1161			fin->fin_cksum = FI_CK_BAD;
1162			fin->fin_flx |= FI_BAD;
1163		} else {
1164			fin->fin_cksum = FI_CK_SUMOK;
1165			return 0;
1166		}
1167	} else {
1168		if (m->m_pkthdr.csum_flags == CSUM_DELAY_DATA) {
1169			fin->fin_cksum = FI_CK_L4FULL;
1170			return 0;
1171		} else if (m->m_pkthdr.csum_flags == CSUM_TCP ||
1172			   m->m_pkthdr.csum_flags == CSUM_UDP) {
1173			fin->fin_cksum = FI_CK_L4PART;
1174			return 0;
1175		} else if (m->m_pkthdr.csum_flags == CSUM_IP) {
1176			fin->fin_cksum = FI_CK_L4PART;
1177			return 0;
1178		} else {
1179			manual = 1;
1180		}
1181	}
1182skipauto:
1183	if (manual != 0) {
1184		if (ipf_checkl4sum(fin) == -1) {
1185			fin->fin_flx |= FI_BAD;
1186			return -1;
1187		}
1188	}
1189#else
1190	if (ipf_checkl4sum(fin) == -1) {
1191		fin->fin_flx |= FI_BAD;
1192		return -1;
1193	}
1194#endif
1195	return 0;
1196}
1197
1198
1199#ifdef USE_INET6
1200INLINE int
1201ipf_checkv6sum(fin)
1202	fr_info_t *fin;
1203{
1204	if ((fin->fin_flx & FI_NOCKSUM) != 0)
1205		return 0;
1206
1207	if ((fin->fin_flx & FI_SHORT) != 0)
1208		return 1;
1209
1210	if (fin->fin_cksum != FI_CK_NEEDED)
1211		return (fin->fin_cksum > FI_CK_NEEDED) ? 0 : -1;
1212
1213	if (ipf_checkl4sum(fin) == -1) {
1214		fin->fin_flx |= FI_BAD;
1215		return -1;
1216	}
1217	return 0;
1218}
1219#endif /* USE_INET6 */
1220
1221
1222size_t
1223mbufchainlen(m0)
1224	struct mbuf *m0;
1225	{
1226	size_t len;
1227
1228	if ((m0->m_flags & M_PKTHDR) != 0) {
1229		len = m0->m_pkthdr.len;
1230	} else {
1231		struct mbuf *m;
1232
1233		for (m = m0, len = 0; m != NULL; m = m->m_next)
1234			len += m->m_len;
1235	}
1236	return len;
1237}
1238
1239
1240/* ------------------------------------------------------------------------ */
1241/* Function:    ipf_pullup                                                  */
1242/* Returns:     NULL == pullup failed, else pointer to protocol header      */
1243/* Parameters:  xmin(I)- pointer to buffer where data packet starts         */
1244/*              fin(I) - pointer to packet information                      */
1245/*              len(I) - number of bytes to pullup                          */
1246/*                                                                          */
1247/* Attempt to move at least len bytes (from the start of the buffer) into a */
1248/* single buffer for ease of access.  Operating system native functions are */
1249/* used to manage buffers - if necessary.  If the entire packet ends up in  */
1250/* a single buffer, set the FI_COALESCE flag even though ipf_coalesce() has */
1251/* not been called.  Both fin_ip and fin_dp are updated before exiting _IF_ */
1252/* and ONLY if the pullup succeeds.                                         */
1253/*                                                                          */
1254/* We assume that 'xmin' is a pointer to a buffer that is part of the chain */
1255/* of buffers that starts at *fin->fin_mp.                                  */
1256/* ------------------------------------------------------------------------ */
1257void *
1258ipf_pullup(xmin, fin, len)
1259	mb_t *xmin;
1260	fr_info_t *fin;
1261	int len;
1262{
1263	int dpoff, ipoff;
1264	mb_t *m = xmin;
1265	char *ip;
1266
1267	if (m == NULL)
1268		return NULL;
1269
1270	ip = (char *)fin->fin_ip;
1271	if ((fin->fin_flx & FI_COALESCE) != 0)
1272		return ip;
1273
1274	ipoff = fin->fin_ipoff;
1275	if (fin->fin_dp != NULL)
1276		dpoff = (char *)fin->fin_dp - (char *)ip;
1277	else
1278		dpoff = 0;
1279
1280	if (M_LEN(m) < len) {
1281		mb_t *n = *fin->fin_mp;
1282		/*
1283		 * Assume that M_PKTHDR is set and just work with what is left
1284		 * rather than check..
1285		 * Should not make any real difference, anyway.
1286		 */
1287		if (m != n) {
1288			/*
1289			 * Record the mbuf that points to the mbuf that we're
1290			 * about to go to work on so that we can update the
1291			 * m_next appropriately later.
1292			 */
1293			for (; n->m_next != m; n = n->m_next)
1294				;
1295		} else {
1296			n = NULL;
1297		}
1298
1299#ifdef MHLEN
1300		if (len > MHLEN)
1301#else
1302		if (len > MLEN)
1303#endif
1304		{
1305#ifdef HAVE_M_PULLDOWN
1306			if (m_pulldown(m, 0, len, NULL) == NULL)
1307				m = NULL;
1308#else
1309			FREE_MB_T(*fin->fin_mp);
1310			m = NULL;
1311			n = NULL;
1312#endif
1313		} else
1314		{
1315			m = m_pullup(m, len);
1316		}
1317		if (n != NULL)
1318			n->m_next = m;
1319		if (m == NULL) {
1320			/*
1321			 * When n is non-NULL, it indicates that m pointed to
1322			 * a sub-chain (tail) of the mbuf and that the head
1323			 * of this chain has not yet been free'd.
1324			 */
1325			if (n != NULL) {
1326				FREE_MB_T(*fin->fin_mp);
1327			}
1328
1329			*fin->fin_mp = NULL;
1330			fin->fin_m = NULL;
1331			return NULL;
1332		}
1333
1334		if (n == NULL)
1335			*fin->fin_mp = m;
1336
1337		while (M_LEN(m) == 0) {
1338			m = m->m_next;
1339		}
1340		fin->fin_m = m;
1341		ip = MTOD(m, char *) + ipoff;
1342
1343		fin->fin_ip = (ip_t *)ip;
1344		if (fin->fin_dp != NULL)
1345			fin->fin_dp = (char *)fin->fin_ip + dpoff;
1346		if (fin->fin_fraghdr != NULL)
1347			fin->fin_fraghdr = (char *)ip +
1348					   ((char *)fin->fin_fraghdr -
1349					    (char *)fin->fin_ip);
1350	}
1351
1352	if (len == fin->fin_plen)
1353		fin->fin_flx |= FI_COALESCE;
1354	return ip;
1355}
1356
1357
1358int
1359ipf_inject(fin, m)
1360	fr_info_t *fin;
1361	mb_t *m;
1362{
1363	int error = 0;
1364
1365	if (fin->fin_out == 0) {
1366		netisr_dispatch(NETISR_IP, m);
1367	} else {
1368		fin->fin_ip->ip_len = ntohs(fin->fin_ip->ip_len);
1369		fin->fin_ip->ip_off = ntohs(fin->fin_ip->ip_off);
1370		error = ip_output(m, NULL, NULL, IP_FORWARDING, NULL, NULL);
1371	}
1372
1373	return error;
1374}
1375
1376int ipf_pfil_unhook(void) {
1377#if defined(NETBSD_PF) && (__FreeBSD_version >= 500011)
1378	struct pfil_head *ph_inet;
1379#  ifdef USE_INET6
1380	struct pfil_head *ph_inet6;
1381#  endif
1382#endif
1383
1384#ifdef NETBSD_PF
1385	ph_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
1386	if (ph_inet != NULL)
1387		pfil_remove_hook((void *)ipf_check_wrapper, NULL,
1388		    PFIL_IN|PFIL_OUT|PFIL_WAITOK, ph_inet);
1389# ifdef USE_INET6
1390	ph_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
1391	if (ph_inet6 != NULL)
1392		pfil_remove_hook((void *)ipf_check_wrapper6, NULL,
1393		    PFIL_IN|PFIL_OUT|PFIL_WAITOK, ph_inet6);
1394# endif
1395#endif
1396
1397	return (0);
1398}
1399
1400int ipf_pfil_hook(void) {
1401#if defined(NETBSD_PF) && (__FreeBSD_version >= 500011)
1402	struct pfil_head *ph_inet;
1403#  ifdef USE_INET6
1404	struct pfil_head *ph_inet6;
1405#  endif
1406#endif
1407
1408# ifdef NETBSD_PF
1409	ph_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
1410#    ifdef USE_INET6
1411	ph_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
1412#    endif
1413	if (ph_inet == NULL
1414#    ifdef USE_INET6
1415	    && ph_inet6 == NULL
1416#    endif
1417	   ) {
1418		return ENODEV;
1419	}
1420
1421	if (ph_inet != NULL)
1422		pfil_add_hook((void *)ipf_check_wrapper, NULL,
1423		    PFIL_IN|PFIL_OUT|PFIL_WAITOK, ph_inet);
1424#  ifdef USE_INET6
1425	if (ph_inet6 != NULL)
1426		pfil_add_hook((void *)ipf_check_wrapper6, NULL,
1427				      PFIL_IN|PFIL_OUT|PFIL_WAITOK, ph_inet6);
1428#  endif
1429# endif
1430	return (0);
1431}
1432
1433void
1434ipf_event_reg(void)
1435{
1436	ipf_arrivetag = EVENTHANDLER_REGISTER(ifnet_arrival_event, \
1437					       ipf_ifevent, &ipfmain, \
1438					       EVENTHANDLER_PRI_ANY);
1439	ipf_departtag = EVENTHANDLER_REGISTER(ifnet_departure_event, \
1440					       ipf_ifevent, &ipfmain, \
1441					       EVENTHANDLER_PRI_ANY);
1442	ipf_clonetag  = EVENTHANDLER_REGISTER(if_clone_event, ipf_ifevent, \
1443					       &ipfmain, EVENTHANDLER_PRI_ANY);
1444}
1445
1446void
1447ipf_event_dereg(void)
1448{
1449	if (ipf_arrivetag != NULL) {
1450		EVENTHANDLER_DEREGISTER(ifnet_arrival_event, ipf_arrivetag);
1451	}
1452	if (ipf_departtag != NULL) {
1453		EVENTHANDLER_DEREGISTER(ifnet_departure_event, ipf_departtag);
1454	}
1455	if (ipf_clonetag != NULL) {
1456		EVENTHANDLER_DEREGISTER(if_clone_event, ipf_clonetag);
1457	}
1458}
1459
1460
1461u_32_t
1462ipf_random()
1463{
1464	return arc4random();
1465}
1466
1467
1468u_int
1469ipf_pcksum(fin, hlen, sum)
1470	fr_info_t *fin;
1471	int hlen;
1472	u_int sum;
1473{
1474	struct mbuf *m;
1475	u_int sum2;
1476	int off;
1477
1478	m = fin->fin_m;
1479	off = (char *)fin->fin_dp - (char *)fin->fin_ip;
1480	m->m_data += hlen;
1481	m->m_len -= hlen;
1482	sum2 = in_cksum(fin->fin_m, fin->fin_plen - off);
1483	m->m_len += hlen;
1484	m->m_data -= hlen;
1485
1486	/*
1487	 * Both sum and sum2 are partial sums, so combine them together.
1488	 */
1489	sum += ~sum2 & 0xffff;
1490	while (sum > 0xffff)
1491		sum = (sum & 0xffff) + (sum >> 16);
1492	sum2 = ~sum & 0xffff;
1493	return sum2;
1494}
1495