Lines Matching +full:is +full:- +full:decoded +full:- +full:cs
1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
4 * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
5 * based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
111 { 1, "IN" }, { 2, "CS" }, { 3, "CH" }, { 4, "HS" }, { 255, "*" }
136 { 23, "NSAP-PTR" }, { 24, "SIG" }, { 25, "KEY" }, { 26, "PX" },
167 * The purpose of this routine is calculate this result, for
168 * the many times it is needed in FilterCheck, only on demand
177 * The caching performed here is just a side effect.
182 static int oproto = -1;
183 static char protobuff[16] = "-1";
191 snprintf(protobuff, sizeof protobuff, "%s", pe->p_name);
198 * Returns 0 to accept the packet, non-zero to drop the packet.
199 * If psecs is not NULL, populate it with the timeout associated
202 * If filtering is enabled, the initial fragment of a datagram must
204 * must not attempt to over-write it.
217 int gotinfo; /* true if IP payload decoded */
226 const struct filterent *fp = filter->rule;
232 if (fp->f_action == A_NONE)
233 return 0; /* No rule is given. Permit this packet */
239 ncpaddr_setip6(&srcaddr, &pip6->ip6_src);
240 ncpaddr_setip6(&dstaddr, &pip6->ip6_dst);
241 datalen = ntohs(pip6->ip6_plen);
243 cproto = pip6->ip6_nxt;
248 * Deny any packet fragment that tries to over-write the header.
250 * largest normal header - 20 bytes for TCP without options, rounded
252 * `legal' MTU is 576, and the smallest recommended MTU is 296, any
253 * fragmentation within this range is dubious at best
257 len = ntohs(pip->ip_off) & IP_OFFMASK; /* fragment offset */
259 if (len < (24 >> 3)) { /* don't allow fragment to over-write header */
264 if (!filter->fragok) {
271 ncpaddr_setip4(&srcaddr, pip->ip_src);
272 ncpaddr_setip4(&dstaddr, pip->ip_dst);
273 datalen = ntohs(pip->ip_len) - (pip->ip_hl << 2);
274 payload = packet + (pip->ip_hl << 2);
275 cproto = pip->ip_p;
283 if (fp->f_action == A_NONE) {
290 log_Printf(LogDEBUG, "%s filter:\n", filter->name);
296 if ((ncprange_family(&fp->f_src) == AF_UNSPEC ||
297 ncprange_contains(&fp->f_src, &srcaddr)) &&
298 (ncprange_family(&fp->f_dst) == AF_UNSPEC ||
299 ncprange_contains(&fp->f_dst, &dstaddr))) {
300 if (fp->f_proto != 0) {
310 estab = syn = finrst = -1;
316 sport = ih->icmp_type;
325 sport = ih6->icmp6_type;
332 mindata = 8; /* IGMP uses 8-octet messages */
337 mindata = 2; /* GRE uses 2-octet+ messages */
342 mindata = 8; /* IGMP uses 8-octet messages */
352 mindata = 8; /* UDP header is 8 octets */
354 sport = ntohs(uh->uh_sport);
355 dport = ntohs(uh->uh_dport);
365 * ensures that the TCP header length isn't de-referenced if
366 * the datagram is too short
368 if (datalen < 20 || datalen < (th->th_off << 2)) {
372 sport = ntohs(th->th_sport);
373 dport = ntohs(th->th_dport);
397 if (estab != -1) {
399 snprintf(dbuff + len, sizeof dbuff - len,
410 if (fp->f_srcop != OP_NONE) {
412 filter_Op2Nam(fp->f_srcop), fp->f_srcport);
416 if (fp->f_dstop != OP_NONE) {
417 snprintf(dbuff + len, sizeof dbuff - len,
418 ", dst %s %d", filter_Op2Nam(fp->f_dstop),
419 fp->f_dstport);
425 n, fp->f_proto, dbuff, filter_Action2Nam(fp->f_action));
428 if (cproto == fp->f_proto) {
429 if ((fp->f_srcop == OP_NONE ||
430 PortMatch(fp->f_srcop, sport, fp->f_srcport)) &&
431 (fp->f_dstop == OP_NONE ||
432 PortMatch(fp->f_dstop, dport, fp->f_dstport)) &&
433 (fp->f_estab == 0 || estab) &&
434 (fp->f_syn == 0 || syn) &&
435 (fp->f_finrst == 0 || finrst)) {
440 /* Address is matched and no protocol specified. Make a decision. */
442 filter_Action2Nam(fp->f_action));
448 if (match != fp->f_invert) {
450 if (fp->f_action < A_NONE)
451 fp = &filter->rule[n = fp->f_action];
453 if (fp->f_action == A_PERMIT) {
455 *psecs = fp->timeout;
456 if (strcmp(filter->name, "DIAL") == 0) {
461 "src = %s:%d dst = %s:%d\n", filter->name, n,
472 filter->name, n, prototxt(cproto),
488 filter->name, prototxt(cproto), ncpaddr_ntoa(&srcaddr),
505 len = ntohs(uh->uh_ulen) - sizeof *uh;
512 len -= sizeof header;
515 *hptr++ = ntohs(*pktptr); /* Careful of macro side-effects ! */
526 end = ptr + len - 4;
527 if (end - ptr >= (int)sizeof namewithdot)
528 end = ptr + sizeof namewithdot - 1;
531 if ((int)len > end - ptr)
532 len = end - ptr;
579 (!filter || filter->logok);
587 ncpaddr_setip6(&srcaddr, &pip6->ip6_src);
588 ncpaddr_setip6(&dstaddr, &pip6->ip6_dst);
589 datalen = ntohs(pip6->ip6_plen);
591 cproto = pip6->ip6_nxt;
592 tos = 0; /* XXX: pip6->ip6_vfc >> 4 ? */
599 ncpaddr_setip4(&srcaddr, pip->ip_src);
600 ncpaddr_setip4(&dstaddr, pip->ip_dst);
601 datalen = ntohs(pip->ip_len) - (pip->ip_hl << 2);
602 payload = packet + (pip->ip_hl << 2);
603 cproto = pip->ip_p;
604 tos = pip->ip_tos;
605 frag = ntohs(pip->ip_off) & IP_OFFMASK;
612 snprintf(logbuf + loglen, sizeof logbuf - loglen, "%s", prefix);
614 snprintf(logbuf + loglen, sizeof logbuf - loglen, "%s ", filter->name);
616 snprintf(logbuf + loglen, sizeof logbuf - loglen, " ");
623 len = datalen - sizeof *icmph;
625 snprintf(logbuf + loglen, sizeof logbuf - loglen,
626 "ICMP: %s:%d ---> ", ncpaddr_ntoa(&srcaddr), icmph->icmp_type);
628 snprintf(logbuf + loglen, sizeof logbuf - loglen,
637 len = datalen - sizeof *icmp6h;
639 snprintf(logbuf + loglen, sizeof logbuf - loglen,
640 "ICMP: %s:%d ---> ", ncpaddr_ntoa(&srcaddr), icmp6h->icmp6_type);
642 snprintf(logbuf + loglen, sizeof logbuf - loglen,
651 if (tos == IPTOS_LOWDELAY && bundle->ncp.cfg.urgent.tos)
654 if (!frag && ncp_IsUrgentUdpPort(&bundle->ncp, ntohs(uh->uh_sport),
655 ntohs(uh->uh_dport)))
659 len = datalen - sizeof *uh;
660 snprintf(logbuf + loglen, sizeof logbuf - loglen,
661 "UDP: %s:%d ---> ", ncpaddr_ntoa(&srcaddr), ntohs(uh->uh_sport));
663 snprintf(logbuf + loglen, sizeof logbuf - loglen,
664 "%s:%d (%d/%d)", ncpaddr_ntoa(&dstaddr), ntohs(uh->uh_dport),
680 snprintf(logbuf + loglen, sizeof logbuf - loglen, " contains ");
682 nb - (payload - packet) - sizeof *uh - 4, filter,
684 if (result != -2)
691 case PROTO_MP: type = "Multi-link"; break;
702 snprintf(logbuf + loglen, sizeof logbuf - loglen,
703 " - %s data", type);
713 snprintf(logbuf + loglen, sizeof logbuf - loglen,
714 "GRE: %s ---> ", ncpaddr_ntoa(&srcaddr));
716 snprintf(logbuf + loglen, sizeof logbuf - loglen,
726 snprintf(logbuf + loglen, sizeof logbuf - loglen,
727 "OSPF: %s ---> ", ncpaddr_ntoa(&srcaddr));
729 snprintf(logbuf + loglen, sizeof logbuf - loglen,
739 snprintf(logbuf + loglen, sizeof logbuf - loglen,
740 "IPv6: %s ---> ", ncpaddr_ntoa(&srcaddr));
742 snprintf(logbuf + loglen, sizeof logbuf - loglen,
748 snprintf(logbuf + loglen, sizeof logbuf - loglen, " contains ");
749 result = PacketCheck(bundle, AF_INET6, payload, nb - (payload - packet),
751 if (result != -2)
759 snprintf(logbuf + loglen, sizeof logbuf - loglen,
760 "IPIP: %s ---> ", ncpaddr_ntoa(&srcaddr));
762 snprintf(logbuf + loglen, sizeof logbuf - loglen,
768 ((const struct ip *)payload)->ip_v == 4) {
769 snprintf(logbuf + loglen, sizeof logbuf - loglen, " contains ");
770 result = PacketCheck(bundle, AF_INET, payload, nb - (payload - packet),
773 if (result != -2)
780 snprintf(logbuf + loglen, sizeof logbuf - loglen,
781 "ESP: %s ---> ", ncpaddr_ntoa(&srcaddr));
783 snprintf(logbuf + loglen, sizeof logbuf - loglen, "%s, spi %p",
791 snprintf(logbuf + loglen, sizeof logbuf - loglen,
792 "AH: %s ---> ", ncpaddr_ntoa(&srcaddr));
794 snprintf(logbuf + loglen, sizeof logbuf - loglen, "%s, spi %p",
803 snprintf(logbuf + loglen, sizeof logbuf - loglen,
804 "IGMP: %s:%d ---> ", ncpaddr_ntoa(&srcaddr),
805 ntohs(uh->uh_sport));
807 snprintf(logbuf + loglen, sizeof logbuf - loglen,
808 "%s:%d", ncpaddr_ntoa(&dstaddr), ntohs(uh->uh_dport));
815 if (tos == IPTOS_LOWDELAY && bundle->ncp.cfg.urgent.tos)
818 if (!frag && ncp_IsUrgentTcpPort(&bundle->ncp, ntohs(th->th_sport),
819 ntohs(th->th_dport)))
821 else if (!frag && ncp_IsUrgentTcpLen(&bundle->ncp, datalen))
825 len = datalen - (th->th_off << 2);
826 snprintf(logbuf + loglen, sizeof logbuf - loglen,
827 "TCP: %s:%d ---> ", ncpaddr_ntoa(&srcaddr), ntohs(th->th_sport));
829 snprintf(logbuf + loglen, sizeof logbuf - loglen,
830 "%s:%d", ncpaddr_ntoa(&dstaddr), ntohs(th->th_dport));
834 snprintf(logbuf + loglen, sizeof logbuf - loglen, " %s", TcpFlags[n]);
838 snprintf(logbuf + loglen, sizeof logbuf - loglen,
840 (u_long)ntohl(th->th_seq), (u_long)ntohl(th->th_ack), len, nb);
847 snprintf(logbuf + loglen, sizeof logbuf - loglen,
852 snprintf(logbuf + loglen, sizeof logbuf - loglen, " pri:%d", pri);
859 return -2;
862 snprintf(logbuf + loglen, sizeof logbuf - loglen,
863 "<%d>: %s ---> ", cproto, ncpaddr_ntoa(&srcaddr));
865 snprintf(logbuf + loglen, sizeof logbuf - loglen,
874 log_Printf(LogTCPIP, "%s - BLOCKED\n", logbuf);
875 result = -1;
883 FilterCheck(packet, family, &bundle->filter.alive, &alivesecs))
884 log_Printf(LogTCPIP, "%s - NO KEEPALIVE\n", logbuf);
890 log_Printf(LogTCPIP, "%s - (timeout = %d / ALIVE = %d secs)\n",
893 log_Printf(LogTCPIP, "%s - (timeout = %d secs)\n", logbuf, *psecs);
901 if (filter && uh && ntohs(uh->uh_dport) == 53 && log_IsKept(LogDNS))
902 ip_LogDNS(uh, filter->name);
919 l->name, nb, (int)(sizeof tun.data));
926 if (PacketCheck(bundle, af, tun.data, nb, &bundle->filter.in,
931 if (!FilterCheck(tun.data, af, &bundle->filter.alive, &alivesecs)) {
937 if (bundle->dev.header) {
939 nb += sizeof tun - sizeof tun.data;
944 nw = write(bundle->dev.fd, data, nb);
946 if (nw == -1)
948 l->name, nb, strerror(errno));
950 log_Printf(LogERROR, "ip_Input: %s: wrote %zd, got %zd\n", l->name, nb,
962 if (bundle->ncp.ipcp.fsm.state != ST_OPENED) {
963 log_Printf(LogWARN, "ipv4_Input: IPCP not open - packet dropped\n");
971 ipcp_AddInOctets(&bundle->ncp.ipcp, nb);
982 if (bundle->ncp.ipv6cp.fsm.state != ST_OPENED) {
983 log_Printf(LogWARN, "ipv6_Input: IPV6CP not open - packet dropped\n");
991 ipv6cp_AddInOctets(&bundle->ncp.ipv6cp, nb);