4 * Copyright (C) 2012 by Darren Reed.
6 * See the IPFILTER.LICENCE file for details on licencing.
9 static const char sccsid[] = "@(#)ip_fil.c 2.41 6/5/96 (C) 1993-2000 Darren Reed";
10 static const char rcsid[] = "@(#)$Id$";
13 #if defined(KERNEL) || defined(_KERNEL)
19 #if defined(__FreeBSD_version) && (__FreeBSD_version >= 400000) && \
20 !defined(KLD_MODULE) && !defined(IPFILTER_LKM)
21 # include "opt_inet6.h"
23 #if defined(__FreeBSD_version) && (__FreeBSD_version >= 440000) && \
24 !defined(KLD_MODULE) && !defined(IPFILTER_LKM)
25 # include "opt_random_ip_id.h"
27 #include <sys/param.h>
28 #include <sys/errno.h>
29 #include <sys/types.h>
31 # include <sys/fcntl.h>
32 # include <sys/filio.h>
34 #include <sys/systm.h>
35 # include <sys/dirent.h>
36 #if defined(__FreeBSD_version) && (__FreeBSD_version >= 800000)
39 # include <sys/malloc.h>
40 # include <sys/mbuf.h>
41 # include <sys/sockopt.h>
43 # include <sys/mbuf.h>
45 #include <sys/socket.h>
46 # include <sys/selinfo.h>
47 # include <netinet/tcp_var.h>
50 # include <net/if_var.h>
51 # include <net/netisr.h>
52 #include <net/route.h>
53 #include <netinet/in.h>
54 #include <netinet/in_fib.h>
55 #include <netinet/in_var.h>
56 #include <netinet/in_systm.h>
57 #include <netinet/ip.h>
58 #include <netinet/ip_var.h>
59 #include <netinet/tcp.h>
61 #include <netinet/udp.h>
62 #include <netinet/tcpip.h>
63 #include <netinet/ip_icmp.h>
64 #include "netinet/ip_compat.h"
66 # include <netinet/icmp6.h>
68 #include "netinet/ip_fil.h"
69 #include "netinet/ip_nat.h"
70 #include "netinet/ip_frag.h"
71 #include "netinet/ip_state.h"
72 #include "netinet/ip_proxy.h"
73 #include "netinet/ip_auth.h"
74 #include "netinet/ip_sync.h"
75 #include "netinet/ip_lookup.h"
76 #include "netinet/ip_dstlist.h"
78 #include "netinet/ip_scan.h"
80 #include "netinet/ip_pool.h"
81 # include <sys/malloc.h>
82 #include <sys/kernel.h>
83 #ifdef CSUM_DATA_VALID
84 #include <machine/in_cksum.h>
86 extern int ip_optcopy __P((struct ip *, struct ip *));
89 # ifdef IPFILTER_M_IPFILTER
90 MALLOC_DEFINE(M_IPFILTER, "ipfilter", "IP Filter packet filter data structures");
94 static int ipf_send_ip __P((fr_info_t *, mb_t *));
95 static void ipf_timer_func __P((void *arg));
97 VNET_DEFINE(ipf_main_softc_t, ipfmain) = {
100 #define V_ipfmain VNET(ipfmain)
102 # include <sys/conf.h>
103 # if defined(NETBSD_PF)
104 # include <net/pfil.h>
105 # endif /* NETBSD_PF */
107 static eventhandler_tag ipf_arrivetag, ipf_departtag;
110 * Disable the "cloner" event handler; we are getting interface
111 * events before the firewall is fully initiallized and also no vnet
112 * information thus leading to uninitialised memory accesses.
113 * In addition it is unclear why we need it in first place.
114 * If it turns out to be needed, well need a dedicated event handler
115 * for it to deal with the ifc and the correct vnet.
117 static eventhandler_tag ipf_clonetag;
120 static void ipf_ifevent(void *arg, struct ifnet *ifp);
122 static void ipf_ifevent(arg, ifp)
127 CURVNET_SET(ifp->if_vnet);
128 if (V_ipfmain.ipf_running > 0)
129 ipf_sync(&V_ipfmain, NULL);
136 ipf_check_wrapper(void *arg, struct mbuf **mp, struct ifnet *ifp, int dir)
138 struct ip *ip = mtod(*mp, struct ip *);
142 * IPFilter expects evreything in network byte order
144 #if (__FreeBSD_version < 1000019)
145 ip->ip_len = htons(ip->ip_len);
146 ip->ip_off = htons(ip->ip_off);
148 CURVNET_SET(ifp->if_vnet);
149 rv = ipf_check(&V_ipfmain, ip, ip->ip_hl << 2, ifp, (dir == PFIL_OUT),
152 #if (__FreeBSD_version < 1000019)
153 if ((rv == 0) && (*mp != NULL)) {
154 ip = mtod(*mp, struct ip *);
155 ip->ip_len = ntohs(ip->ip_len);
156 ip->ip_off = ntohs(ip->ip_off);
163 # include <netinet/ip6.h>
166 ipf_check_wrapper6(void *arg, struct mbuf **mp, struct ifnet *ifp, int dir)
170 CURVNET_SET(ifp->if_vnet);
171 error = ipf_check(&V_ipfmain, mtod(*mp, struct ip *),
172 sizeof(struct ip6_hdr), ifp, (dir == PFIL_OUT), mp);
177 #if defined(IPFILTER_LKM)
181 if (strcmp(s, "ipl") == 0)
185 #endif /* IPFILTER_LKM */
192 ipf_main_softc_t *softc = arg;
196 READ_ENTER(&softc->ipf_global);
198 if (softc->ipf_running > 0)
199 ipf_slowtimer(softc);
201 if (softc->ipf_running == -1 || softc->ipf_running == 1) {
203 softc->ipf_slow_ch = timeout(ipf_timer_func, softc, hz/2);
205 callout_init(&softc->ipf_slow_ch, 1);
206 callout_reset(&softc->ipf_slow_ch,
207 (hz / IPF_HZ_DIVIDE) * IPF_HZ_MULT,
208 ipf_timer_func, softc);
210 RWLOCK_EXIT(&softc->ipf_global);
217 ipf_main_softc_t *softc;
224 if (softc->ipf_running > 0) {
229 if (ipf_init_all(softc) < 0) {
235 bzero((char *)V_ipfmain.ipf_selwait, sizeof(V_ipfmain.ipf_selwait));
236 softc->ipf_running = 1;
238 if (softc->ipf_control_forwarding & 1)
243 softc->ipf_slow_ch = timeout(ipf_timer_func, softc,
244 (hz / IPF_HZ_DIVIDE) * IPF_HZ_MULT);
246 callout_init(&softc->ipf_slow_ch, 1);
247 callout_reset(&softc->ipf_slow_ch, (hz / IPF_HZ_DIVIDE) * IPF_HZ_MULT,
248 ipf_timer_func, softc);
254 * Disable the filter by removing the hooks from the IP input/output
259 ipf_main_softc_t *softc;
265 if (softc->ipf_control_forwarding & 2)
271 if (softc->ipf_slow_ch.callout != NULL)
272 untimeout(ipf_timer_func, softc, softc->ipf_slow_ch);
273 bzero(&softc->ipf_slow, sizeof(softc->ipf_slow));
275 callout_drain(&softc->ipf_slow_ch);
279 softc->ipf_running = -2;
288 * Filter ioctl interface.
291 ipfioctl(dev, cmd, data, mode
294 # define p_cred td_ucred
295 # define p_uid td_ucred->cr_ruid
301 int error = 0, unit = 0;
304 CURVNET_SET(TD_TO_VNET(p));
306 if (securelevel_ge(p->p_cred, 3) && (mode & FWRITE))
308 V_ipfmain.ipf_interror = 130001;
314 unit = GET_MINOR(dev);
315 if ((IPL_LOGMAX < unit) || (unit < 0)) {
316 V_ipfmain.ipf_interror = 130002;
321 if (V_ipfmain.ipf_running <= 0) {
322 if (unit != IPL_LOGIPF && cmd != SIOCIPFINTERROR) {
323 V_ipfmain.ipf_interror = 130003;
327 if (cmd != SIOCIPFGETNEXT && cmd != SIOCIPFGET &&
328 cmd != SIOCIPFSET && cmd != SIOCFRENB &&
329 cmd != SIOCGETFS && cmd != SIOCGETFF &&
330 cmd != SIOCIPFINTERROR) {
331 V_ipfmain.ipf_interror = 130004;
339 error = ipf_ioctlswitch(&V_ipfmain, unit, data, cmd, mode, p->p_uid, p);
353 * ipf_send_reset - this could conceivably be a call to tcp_respond(), but that
354 * requires a large amount of setting up and isn't any more efficient.
360 struct tcphdr *tcp, *tcp2;
369 if (tcp->th_flags & TH_RST)
370 return -1; /* feedback loop */
372 if (ipf_checkl4sum(fin) == -1)
375 tlen = fin->fin_dlen - (TCP_OFF(tcp) << 2) +
376 ((tcp->th_flags & TH_SYN) ? 1 : 0) +
377 ((tcp->th_flags & TH_FIN) ? 1 : 0);
380 hlen = (fin->fin_v == 6) ? sizeof(ip6_t) : sizeof(ip_t);
385 MGETHDR(m, M_NOWAIT, MT_HEADER);
387 MGET(m, M_NOWAIT, MT_HEADER);
391 if (sizeof(*tcp2) + hlen > MLEN) {
392 if (!(MCLGET(m, M_NOWAIT))) {
398 m->m_len = sizeof(*tcp2) + hlen;
400 m->m_data += max_linkhdr;
401 m->m_pkthdr.len = m->m_len;
402 m->m_pkthdr.rcvif = (struct ifnet *)0;
404 ip = mtod(m, struct ip *);
405 bzero((char *)ip, hlen);
409 tcp2 = (struct tcphdr *)((char *)ip + hlen);
410 tcp2->th_sport = tcp->th_dport;
411 tcp2->th_dport = tcp->th_sport;
413 if (tcp->th_flags & TH_ACK) {
414 tcp2->th_seq = tcp->th_ack;
415 tcp2->th_flags = TH_RST;
419 tcp2->th_ack = ntohl(tcp->th_seq);
420 tcp2->th_ack += tlen;
421 tcp2->th_ack = htonl(tcp2->th_ack);
422 tcp2->th_flags = TH_RST|TH_ACK;
425 TCP_OFF_A(tcp2, sizeof(*tcp2) >> 2);
426 tcp2->th_win = tcp->th_win;
431 if (fin->fin_v == 6) {
432 ip6->ip6_flow = ((ip6_t *)fin->fin_ip)->ip6_flow;
433 ip6->ip6_plen = htons(sizeof(struct tcphdr));
434 ip6->ip6_nxt = IPPROTO_TCP;
436 ip6->ip6_src = fin->fin_dst6.in6;
437 ip6->ip6_dst = fin->fin_src6.in6;
438 tcp2->th_sum = in6_cksum(m, IPPROTO_TCP,
439 sizeof(*ip6), sizeof(*tcp2));
440 return ipf_send_ip(fin, m);
443 ip->ip_p = IPPROTO_TCP;
444 ip->ip_len = htons(sizeof(struct tcphdr));
445 ip->ip_src.s_addr = fin->fin_daddr;
446 ip->ip_dst.s_addr = fin->fin_saddr;
447 tcp2->th_sum = in_cksum(m, hlen + sizeof(*tcp2));
448 ip->ip_len = htons(hlen + sizeof(*tcp2));
449 return ipf_send_ip(fin, m);
454 * ip_len must be in network byte order when called.
465 ip = mtod(m, ip_t *);
466 bzero((char *)&fnew, sizeof(fnew));
467 fnew.fin_main_soft = fin->fin_main_soft;
469 IP_V_A(ip, fin->fin_v);
476 fnew.fin_p = ip->ip_p;
477 fnew.fin_plen = ntohs(ip->ip_len);
478 IP_HL_A(ip, sizeof(*oip) >> 2);
479 ip->ip_tos = oip->ip_tos;
480 ip->ip_id = fin->fin_ip->ip_id;
481 #if defined(FreeBSD) && (__FreeBSD_version > 460000)
482 ip->ip_off = htons(path_mtu_discovery ? IP_DF : 0);
486 ip->ip_ttl = V_ip_defttl;
492 ip6_t *ip6 = (ip6_t *)ip;
495 ip6->ip6_hlim = IPDEFTTL;
498 fnew.fin_p = ip6->ip6_nxt;
500 fnew.fin_plen = ntohs(ip6->ip6_plen) + hlen;
508 m->m_pkthdr.rcvif = NULL;
511 fnew.fin_ifp = fin->fin_ifp;
512 fnew.fin_flx = FI_NOCKSUM;
516 fnew.fin_hlen = hlen;
517 fnew.fin_dp = (char *)ip + hlen;
518 (void) ipf_makefrip(hlen, ip, &fnew);
520 return ipf_fastroute(m, &m, &fnew, NULL);
525 ipf_send_icmp_err(type, fin, dst)
530 int err, hlen, xtra, iclen, ohlen, avail, code;
541 if ((type < 0) || (type >= ICMP_MAXTYPE))
544 code = fin->fin_icode;
547 /* XXX Fix an off by one error: s/>/>=/
549 if ((code < 0) || (code > sizeof(icmptoicmp6unreach)/sizeof(int)))
550 Fix obtained from NetBSD ip_fil_netbsd.c r1.4: */
552 if ((code < 0) || (code >= sizeof(icmptoicmp6unreach)/sizeof(int)))
556 if (ipf_checkl4sum(fin) == -1)
559 MGETHDR(m, M_NOWAIT, MT_HEADER);
561 MGET(m, M_NOWAIT, MT_HEADER);
572 if (fin->fin_v == 4) {
573 if ((fin->fin_p == IPPROTO_ICMP) && !(fin->fin_flx & FI_SHORT))
574 switch (ntohs(fin->fin_data[0]) >> 8)
587 if (ipf_ifpaddr(&V_ipfmain, 4, FRI_NORMAL, ifp,
588 &dst6, NULL) == -1) {
594 dst4.s_addr = fin->fin_daddr;
597 ohlen = fin->fin_hlen;
598 iclen = hlen + offsetof(struct icmp, icmp_ip) + ohlen;
599 if (fin->fin_hlen < fin->fin_plen)
600 xtra = MIN(fin->fin_dlen, 8);
606 else if (fin->fin_v == 6) {
607 hlen = sizeof(ip6_t);
608 ohlen = sizeof(ip6_t);
609 iclen = hlen + offsetof(struct icmp, icmp_ip) + ohlen;
610 type = icmptoicmp6types[type];
611 if (type == ICMP6_DST_UNREACH)
612 code = icmptoicmp6unreach[code];
614 if (iclen + max_linkhdr + fin->fin_plen > avail) {
615 if (!(MCLGET(m, M_NOWAIT))) {
621 xtra = MIN(fin->fin_plen, avail - iclen - max_linkhdr);
622 xtra = MIN(xtra, IPV6_MMTU - iclen);
624 if (ipf_ifpaddr(&V_ipfmain, 6, FRI_NORMAL, ifp,
625 &dst6, NULL) == -1) {
630 dst6 = fin->fin_dst6;
638 avail -= (max_linkhdr + iclen);
646 m->m_data += max_linkhdr;
647 m->m_pkthdr.rcvif = (struct ifnet *)0;
648 m->m_pkthdr.len = iclen;
650 ip = mtod(m, ip_t *);
651 icmp = (struct icmp *)((char *)ip + hlen);
652 ip2 = (ip_t *)&icmp->icmp_ip;
654 icmp->icmp_type = type;
655 icmp->icmp_code = fin->fin_icode;
656 icmp->icmp_cksum = 0;
658 if (type == ICMP_UNREACH && fin->fin_icode == ICMP_UNREACH_NEEDFRAG) {
659 if (fin->fin_mtu != 0) {
660 icmp->icmp_nextmtu = htons(fin->fin_mtu);
662 } else if (ifp != NULL) {
663 icmp->icmp_nextmtu = htons(GETIFMTU_4(ifp));
665 } else { /* make up a number... */
666 icmp->icmp_nextmtu = htons(fin->fin_plen - 20);
671 bcopy((char *)fin->fin_ip, (char *)ip2, ohlen);
675 if (fin->fin_v == 6) {
676 ip6->ip6_flow = ((ip6_t *)fin->fin_ip)->ip6_flow;
677 ip6->ip6_plen = htons(iclen - hlen);
678 ip6->ip6_nxt = IPPROTO_ICMPV6;
680 ip6->ip6_src = dst6.in6;
681 ip6->ip6_dst = fin->fin_src6.in6;
683 bcopy((char *)fin->fin_ip + ohlen,
684 (char *)&icmp->icmp_ip + ohlen, xtra);
685 icmp->icmp_cksum = in6_cksum(m, IPPROTO_ICMPV6,
686 sizeof(*ip6), iclen - hlen);
690 ip->ip_p = IPPROTO_ICMP;
691 ip->ip_src.s_addr = dst4.s_addr;
692 ip->ip_dst.s_addr = fin->fin_saddr;
695 bcopy((char *)fin->fin_ip + ohlen,
696 (char *)&icmp->icmp_ip + ohlen, xtra);
697 icmp->icmp_cksum = ipf_cksum((u_short *)icmp,
699 ip->ip_len = htons(iclen);
700 ip->ip_p = IPPROTO_ICMP;
702 err = ipf_send_ip(fin, m);
710 * m0 - pointer to mbuf where the IP packet starts
711 * mpp - pointer to the mbuf pointer that is the start of the mbuf chain
714 ipf_fastroute(m0, mpp, fin, fdp)
719 register struct ip *ip, *mhip;
720 register struct mbuf *m = *mpp;
721 int len, off, error = 0, hlen, code;
722 struct ifnet *ifp, *sifp;
723 struct sockaddr_in dst;
724 struct nhop4_extended nh4;
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.
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
743 if (M_WRITABLE(m) == 0) {
744 m0 = m_dup(m, M_NOWAIT);
758 if (fin->fin_v == 6) {
760 * currently "to <if>" and "to <if>:ip#" are not supported
763 return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
767 hlen = fin->fin_hlen;
768 ip = mtod(m0, struct ip *);
774 bzero(&dst, sizeof (dst));
775 dst.sin_family = AF_INET;
776 dst.sin_addr = ip->ip_dst;
777 dst.sin_len = sizeof(dst);
780 if ((fr != NULL) && !(fr->fr_flags & FR_KEEPSTATE) && (fdp != NULL) &&
781 (fdp->fd_type == FRD_DSTLIST)) {
782 if (ipf_dstlist_select_node(fin, fdp->fd_ptr, NULL, &node) == 0)
791 if ((ifp == NULL) && ((fr == NULL) || !(fr->fr_flags & FR_FASTROUTE))) {
796 if ((fdp != NULL) && (fdp->fd_ip.s_addr != 0))
797 dst.sin_addr = fdp->fd_ip;
799 fibnum = M_GETFIB(m0);
800 if (fib4_lookup_nh_ext(fibnum, dst.sin_addr, NHR_REF, 0, &nh4) != 0) {
801 if (in_localaddr(ip->ip_dst))
802 error = EHOSTUNREACH;
811 if (nh4.nh_flags & NHF_GATEWAY)
812 dst.sin_addr = nh4.nh_addr;
815 * For input packets which are being "fastrouted", they won't
816 * go back through output filtering and miss their chance to get
817 * NAT'd and counted. Duplicated packets aren't considered to be
818 * part of the normal packet stream, so do not NAT them or pass
819 * them through stateful checking, etc.
821 if ((fdp != &fr->fr_dif) && (fin->fin_out == 0)) {
825 (void) ipf_acctpkt(fin, NULL);
827 if (!fr || !(fr->fr_flags & FR_RETMASK)) {
830 (void) ipf_state_check(fin, &pass);
833 switch (ipf_nat_checkout(fin, NULL))
851 * If small enough for interface, can just send directly.
853 if (ntohs(ip->ip_len) <= ifp->if_mtu) {
855 ip->ip_sum = in_cksum(m, hlen);
856 error = (*ifp->if_output)(ifp, m, (struct sockaddr *)&dst,
862 * Too large for interface; fragment if possible.
863 * Must be able to put at least 8 bytes per fragment.
865 ip_off = ntohs(ip->ip_off);
866 if (ip_off & IP_DF) {
870 len = (ifp->if_mtu - hlen) &~ 7;
877 int mhlen, firstlen = len;
878 struct mbuf **mnext = &m->m_act;
881 * Loop through length of segment after first fragment,
882 * make new header and copy data of each part and link onto chain.
885 mhlen = sizeof (struct ip);
886 for (off = hlen + len; off < ntohs(ip->ip_len); off += len) {
888 MGETHDR(m, M_NOWAIT, MT_HEADER);
890 MGET(m, M_NOWAIT, MT_HEADER);
897 m->m_data += max_linkhdr;
898 mhip = mtod(m, struct ip *);
899 bcopy((char *)ip, (char *)mhip, sizeof(*ip));
900 if (hlen > sizeof (struct ip)) {
901 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
902 IP_HL_A(mhip, mhlen >> 2);
905 mhip->ip_off = ((off - hlen) >> 3) + ip_off;
906 if (off + len >= ntohs(ip->ip_len))
907 len = ntohs(ip->ip_len) - off;
909 mhip->ip_off |= IP_MF;
910 mhip->ip_len = htons((u_short)(len + mhlen));
912 m->m_next = m_copym(m0, off, len, M_NOWAIT);
913 if (m->m_next == 0) {
914 error = ENOBUFS; /* ??? */
917 m->m_pkthdr.len = mhlen + len;
918 m->m_pkthdr.rcvif = NULL;
919 mhip->ip_off = htons((u_short)mhip->ip_off);
921 mhip->ip_sum = in_cksum(m, mhlen);
925 * Update first fragment by trimming what's been copied out
926 * and updating header, then send each fragment (in order).
928 m_adj(m0, hlen + firstlen - ip->ip_len);
929 ip->ip_len = htons((u_short)(hlen + firstlen));
930 ip->ip_off = htons((u_short)IP_MF);
932 ip->ip_sum = in_cksum(m0, hlen);
934 for (m = m0; m; m = m0) {
938 error = (*ifp->if_output)(ifp, m,
939 (struct sockaddr *)&dst,
948 V_ipfmain.ipf_frouteok[0]++;
950 V_ipfmain.ipf_frouteok[1]++;
953 fib4_free_nh_ext(fibnum, &nh4);
957 if (error == EMSGSIZE) {
959 code = fin->fin_icode;
960 fin->fin_icode = ICMP_UNREACH_NEEDFRAG;
962 (void) ipf_send_icmp_err(ICMP_UNREACH, fin, 1);
964 fin->fin_icode = code;
975 struct nhop4_basic nh4;
977 if (fib4_lookup_nh_basic(0, fin->fin_src, 0, 0, &nh4) != 0)
979 return (fin->fin_ifp == nh4.nh_ifp);
984 * return the first IP Address associated with an interface
987 ipf_ifpaddr(softc, v, atype, ifptr, inp, inpmask)
988 ipf_main_softc_t *softc;
991 i6addr_t *inp, *inpmask;
994 struct in6_addr *inp6 = NULL;
996 struct sockaddr *sock, *mask;
997 struct sockaddr_in *sin;
1001 if ((ifptr == NULL) || (ifptr == (void *)-1))
1008 inp->in4.s_addr = 0;
1011 bzero((char *)inp, sizeof(*inp));
1013 ifa = CK_STAILQ_FIRST(&ifp->if_addrhead);
1015 sock = ifa->ifa_addr;
1016 while (sock != NULL && ifa != NULL) {
1017 sin = (struct sockaddr_in *)sock;
1018 if ((v == 4) && (sin->sin_family == AF_INET))
1021 if ((v == 6) && (sin->sin_family == AF_INET6)) {
1022 inp6 = &((struct sockaddr_in6 *)sin)->sin6_addr;
1023 if (!IN6_IS_ADDR_LINKLOCAL(inp6) &&
1024 !IN6_IS_ADDR_LOOPBACK(inp6))
1028 ifa = CK_STAILQ_NEXT(ifa, ifa_link);
1030 sock = ifa->ifa_addr;
1033 if (ifa == NULL || sin == NULL)
1036 mask = ifa->ifa_netmask;
1037 if (atype == FRI_BROADCAST)
1038 sock = ifa->ifa_broadaddr;
1039 else if (atype == FRI_PEERADDR)
1040 sock = ifa->ifa_dstaddr;
1047 return ipf_ifpfillv6addr(atype, (struct sockaddr_in6 *)sock,
1048 (struct sockaddr_in6 *)mask,
1052 return ipf_ifpfillv4addr(atype, (struct sockaddr_in *)sock,
1053 (struct sockaddr_in *)mask,
1054 &inp->in4, &inpmask->in4);
1063 newiss = arc4random();
1072 #ifdef CSUM_DATA_VALID
1078 if ((fin->fin_flx & FI_NOCKSUM) != 0)
1081 if ((fin->fin_flx & FI_SHORT) != 0)
1084 if (fin->fin_cksum != FI_CK_NEEDED)
1085 return (fin->fin_cksum > FI_CK_NEEDED) ? 0 : -1;
1094 if ((m->m_pkthdr.csum_flags & (CSUM_IP_CHECKED|CSUM_IP_VALID)) ==
1096 fin->fin_cksum = FI_CK_BAD;
1097 fin->fin_flx |= FI_BAD;
1098 DT2(ipf_fi_bad_checkv4sum_csum_ip_checked, fr_info_t *, fin, u_int, m->m_pkthdr.csum_flags & (CSUM_IP_CHECKED|CSUM_IP_VALID));
1101 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
1102 /* Depending on the driver, UDP may have zero checksum */
1103 if (fin->fin_p == IPPROTO_UDP && (fin->fin_flx &
1104 (FI_FRAG|FI_SHORT|FI_BAD)) == 0) {
1105 udphdr_t *udp = fin->fin_dp;
1106 if (udp->uh_sum == 0) {
1108 * we're good no matter what the hardware
1109 * checksum flags and csum_data say (handling
1110 * of csum_data for zero UDP checksum is not
1111 * consistent across all drivers)
1118 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
1119 sum = m->m_pkthdr.csum_data;
1121 sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
1122 htonl(m->m_pkthdr.csum_data +
1123 fin->fin_dlen + fin->fin_p));
1126 fin->fin_cksum = FI_CK_BAD;
1127 fin->fin_flx |= FI_BAD;
1128 DT2(ipf_fi_bad_checkv4sum_sum, fr_info_t *, fin, u_int, sum);
1130 fin->fin_cksum = FI_CK_SUMOK;
1134 if (m->m_pkthdr.csum_flags == CSUM_DELAY_DATA) {
1135 fin->fin_cksum = FI_CK_L4FULL;
1137 } else if (m->m_pkthdr.csum_flags == CSUM_TCP ||
1138 m->m_pkthdr.csum_flags == CSUM_UDP) {
1139 fin->fin_cksum = FI_CK_L4PART;
1141 } else if (m->m_pkthdr.csum_flags == CSUM_IP) {
1142 fin->fin_cksum = FI_CK_L4PART;
1150 if (ipf_checkl4sum(fin) == -1) {
1151 fin->fin_flx |= FI_BAD;
1152 DT2(ipf_fi_bad_checkv4sum_manual, fr_info_t *, fin, u_int, manual);
1157 if (ipf_checkl4sum(fin) == -1) {
1158 fin->fin_flx |= FI_BAD;
1159 DT2(ipf_fi_bad_checkv4sum_checkl4sum, fr_info_t *, fin, u_int, -1);
1172 if ((fin->fin_flx & FI_NOCKSUM) != 0) {
1173 DT(ipf_checkv6sum_fi_nocksum);
1177 if ((fin->fin_flx & FI_SHORT) != 0) {
1178 DT(ipf_checkv6sum_fi_short);
1182 if (fin->fin_cksum != FI_CK_NEEDED) {
1183 DT(ipf_checkv6sum_fi_ck_needed);
1184 return (fin->fin_cksum > FI_CK_NEEDED) ? 0 : -1;
1187 if (ipf_checkl4sum(fin) == -1) {
1188 fin->fin_flx |= FI_BAD;
1189 DT2(ipf_fi_bad_checkv6sum_checkl4sum, fr_info_t *, fin, u_int, -1);
1194 #endif /* USE_INET6 */
1203 if ((m0->m_flags & M_PKTHDR) != 0) {
1204 len = m0->m_pkthdr.len;
1208 for (m = m0, len = 0; m != NULL; m = m->m_next)
1215 /* ------------------------------------------------------------------------ */
1216 /* Function: ipf_pullup */
1217 /* Returns: NULL == pullup failed, else pointer to protocol header */
1218 /* Parameters: xmin(I)- pointer to buffer where data packet starts */
1219 /* fin(I) - pointer to packet information */
1220 /* len(I) - number of bytes to pullup */
1222 /* Attempt to move at least len bytes (from the start of the buffer) into a */
1223 /* single buffer for ease of access. Operating system native functions are */
1224 /* used to manage buffers - if necessary. If the entire packet ends up in */
1225 /* a single buffer, set the FI_COALESCE flag even though ipf_coalesce() has */
1226 /* not been called. Both fin_ip and fin_dp are updated before exiting _IF_ */
1227 /* and ONLY if the pullup succeeds. */
1229 /* We assume that 'xmin' is a pointer to a buffer that is part of the chain */
1230 /* of buffers that starts at *fin->fin_mp. */
1231 /* ------------------------------------------------------------------------ */
1233 ipf_pullup(xmin, fin, len)
1245 ip = (char *)fin->fin_ip;
1246 if ((fin->fin_flx & FI_COALESCE) != 0)
1249 ipoff = fin->fin_ipoff;
1250 if (fin->fin_dp != NULL)
1251 dpoff = (char *)fin->fin_dp - (char *)ip;
1255 if (M_LEN(m) < len) {
1256 mb_t *n = *fin->fin_mp;
1258 * Assume that M_PKTHDR is set and just work with what is left
1259 * rather than check..
1260 * Should not make any real difference, anyway.
1264 * Record the mbuf that points to the mbuf that we're
1265 * about to go to work on so that we can update the
1266 * m_next appropriately later.
1268 for (; n->m_next != m; n = n->m_next)
1280 #ifdef HAVE_M_PULLDOWN
1281 if (m_pulldown(m, 0, len, NULL) == NULL)
1284 FREE_MB_T(*fin->fin_mp);
1290 m = m_pullup(m, len);
1296 * When n is non-NULL, it indicates that m pointed to
1297 * a sub-chain (tail) of the mbuf and that the head
1298 * of this chain has not yet been free'd.
1301 FREE_MB_T(*fin->fin_mp);
1304 *fin->fin_mp = NULL;
1312 while (M_LEN(m) == 0) {
1316 ip = MTOD(m, char *) + ipoff;
1318 fin->fin_ip = (ip_t *)ip;
1319 if (fin->fin_dp != NULL)
1320 fin->fin_dp = (char *)fin->fin_ip + dpoff;
1321 if (fin->fin_fraghdr != NULL)
1322 fin->fin_fraghdr = (char *)ip +
1323 ((char *)fin->fin_fraghdr -
1324 (char *)fin->fin_ip);
1327 if (len == fin->fin_plen)
1328 fin->fin_flx |= FI_COALESCE;
1340 if (fin->fin_out == 0) {
1341 netisr_dispatch(NETISR_IP, m);
1343 fin->fin_ip->ip_len = ntohs(fin->fin_ip->ip_len);
1344 fin->fin_ip->ip_off = ntohs(fin->fin_ip->ip_off);
1345 error = ip_output(m, NULL, NULL, IP_FORWARDING, NULL, NULL);
1351 int ipf_pfil_unhook(void) {
1352 #if defined(NETBSD_PF) && (__FreeBSD_version >= 500011)
1353 struct pfil_head *ph_inet;
1355 struct pfil_head *ph_inet6;
1360 ph_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
1361 if (ph_inet != NULL)
1362 pfil_remove_hook((void *)ipf_check_wrapper, NULL,
1363 PFIL_IN|PFIL_OUT|PFIL_WAITOK, ph_inet);
1365 ph_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
1366 if (ph_inet6 != NULL)
1367 pfil_remove_hook((void *)ipf_check_wrapper6, NULL,
1368 PFIL_IN|PFIL_OUT|PFIL_WAITOK, ph_inet6);
1375 int ipf_pfil_hook(void) {
1376 #if defined(NETBSD_PF) && (__FreeBSD_version >= 500011)
1377 struct pfil_head *ph_inet;
1379 struct pfil_head *ph_inet6;
1384 ph_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
1386 ph_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
1396 if (ph_inet != NULL)
1397 pfil_add_hook((void *)ipf_check_wrapper, NULL,
1398 PFIL_IN|PFIL_OUT|PFIL_WAITOK, ph_inet);
1400 if (ph_inet6 != NULL)
1401 pfil_add_hook((void *)ipf_check_wrapper6, NULL,
1402 PFIL_IN|PFIL_OUT|PFIL_WAITOK, ph_inet6);
1411 ipf_arrivetag = EVENTHANDLER_REGISTER(ifnet_arrival_event, \
1412 ipf_ifevent, NULL, \
1413 EVENTHANDLER_PRI_ANY);
1414 ipf_departtag = EVENTHANDLER_REGISTER(ifnet_departure_event, \
1415 ipf_ifevent, NULL, \
1416 EVENTHANDLER_PRI_ANY);
1418 ipf_clonetag = EVENTHANDLER_REGISTER(if_clone_event, ipf_ifevent, \
1419 NULL, EVENTHANDLER_PRI_ANY);
1424 ipf_event_dereg(void)
1426 if (ipf_arrivetag != NULL) {
1427 EVENTHANDLER_DEREGISTER(ifnet_arrival_event, ipf_arrivetag);
1429 if (ipf_departtag != NULL) {
1430 EVENTHANDLER_DEREGISTER(ifnet_departure_event, ipf_departtag);
1433 if (ipf_clonetag != NULL) {
1434 EVENTHANDLER_DEREGISTER(if_clone_event, ipf_clonetag);
1443 return arc4random();
1448 ipf_pcksum(fin, hlen, sum)
1458 off = (char *)fin->fin_dp - (char *)fin->fin_ip;
1461 sum2 = in_cksum(fin->fin_m, fin->fin_plen - off);
1466 * Both sum and sum2 are partial sums, so combine them together.
1468 sum += ~sum2 & 0xffff;
1469 while (sum > 0xffff)
1470 sum = (sum & 0xffff) + (sum >> 16);
1471 sum2 = ~sum & 0xffff;