2 * Copyright (C) 1993-2002 by Darren Reed.
4 * See the IPFILTER.LICENCE file for details on licencing.
6 #if defined(__sgi) && (IRIX > 602)
7 # include <sys/ptimers.h>
13 #include <sys/types.h>
14 #if !defined(__SVR4) && !defined(__svr4__)
17 # include <sys/byteorder.h>
20 #include <sys/param.h>
24 #include <sys/socket.h>
25 #include <sys/ioctl.h>
26 #if defined(sun) && (defined(__svr4__) || defined(__SVR4))
27 # include <sys/ioccom.h>
28 # include <sys/sysmacros.h>
30 #include <netinet/in.h>
31 #include <netinet/in_systm.h>
32 #include <netinet/ip.h>
33 #include <netinet/tcp.h>
35 #if __FreeBSD_version >= 300000
36 # include <net/if_var.h>
39 #include <arpa/nameser.h>
40 #include <arpa/inet.h>
43 #include "netinet/ip_compat.h"
44 #include "netinet/ip_fil.h"
45 #include "netinet/ip_nat.h"
46 #include "netinet/ip_state.h"
47 #include "netinet/ip_proxy.h"
50 #if defined(sun) && !SOLARIS2
51 # define STRERROR(x) sys_errlist[x]
52 extern char *sys_errlist[];
54 # define STRERROR(x) strerror(x)
58 static const char sccsid[] ="@(#)ipnat.c 1.9 6/5/96 (C) 1993 Darren Reed";
59 static const char rcsid[] = "@(#)$Id: natparse.c,v 1.17.2.29 2003/05/15 17:45:34 darrenr Exp $";
64 #define bzero(a,b) memset(a,0,b)
67 extern void printnat __P((ipnat_t *, int));
68 extern int countbits __P((u_32_t));
71 ipnat_t *natparse __P((char *, int, int *));
72 void natparsefile __P((int, char *, int));
73 void nat_setgroupmap __P((struct ipnat *));
76 void nat_setgroupmap(n)
79 if (n->in_outmsk == n->in_inmsk)
81 else if (n->in_flags & IPN_AUTOPORTMAP) {
82 n->in_ippip = ~ntohl(n->in_inmsk);
83 if (n->in_outmsk != 0xffffffff)
84 n->in_ippip /= (~ntohl(n->in_outmsk) + 1);
88 n->in_ppip = USABLE_PORTS / n->in_ippip;
90 n->in_space = USABLE_PORTS * ~ntohl(n->in_outmsk);
92 if (!(n->in_ppip = n->in_pmin))
94 n->in_ippip = USABLE_PORTS / n->in_ppip;
100 * Parse a line of input from the ipnat configuration file
105 * > 0 programmer error
107 ipnat_t *natparse(line, linenum, status)
114 char *dnetm = NULL, *dport = NULL;
115 char *s, *t, *cps[31], **cpp;
117 char *port1a = NULL, *port1b = NULL, *port2a = NULL;
119 *status = 100; /* default to error */
123 * Search for end of line and comment marker, advance of leading spaces
125 if ((s = strchr(line, '\n')))
127 if ((s = strchr(line, '#')))
129 while (*line && isspace(*line))
136 bzero((char *)&ipn, sizeof(ipn));
140 * split line upto into segments.
142 for (i = 0, *cps = strtok(line, " \b\t\r\n"); cps[i] && i < 30; cnt++)
143 cps[++i] = strtok(NULL, " \b\t\r\n");
148 fprintf(stderr, "%d: not enough segments in line\n", linenum);
156 * Check first word is a recognised keyword and then is the interface
158 if (!strcasecmp(*cpp, "map"))
159 ipn.in_redir = NAT_MAP;
160 else if (!strcasecmp(*cpp, "map-block"))
161 ipn.in_redir = NAT_MAPBLK;
162 else if (!strcasecmp(*cpp, "rdr"))
163 ipn.in_redir = NAT_REDIRECT;
164 else if (!strcasecmp(*cpp, "bimap"))
165 ipn.in_redir = NAT_BIMAP;
167 fprintf(stderr, "%d: unknown mapping: \"%s\"\n",
175 strncpy(ipn.in_ifname, *cpp, sizeof(ipn.in_ifname) - 1);
176 ipn.in_ifname[sizeof(ipn.in_ifname) - 1] = '\0';
180 * If the first word after the interface is "from" or is a ! then
181 * the expanded syntax is being used so parse it differently.
183 if (!strcasecmp(*cpp, "from") || (**cpp == '!')) {
184 if (!strcmp(*cpp, "!")) {
186 if (strcasecmp(*cpp, "from")) {
187 fprintf(stderr, "Missing from after !\n");
191 ipn.in_flags |= IPN_NOTSRC;
192 } else if (**cpp == '!') {
193 if (strcasecmp(*cpp + 1, "from")) {
194 fprintf(stderr, "Missing from after !\n");
198 ipn.in_flags |= IPN_NOTSRC;
200 if ((ipn.in_flags & IPN_NOTSRC) &&
201 (ipn.in_redir & (NAT_MAP|NAT_MAPBLK))) {
202 fprintf(stderr, "Cannot use '! from' with map\n");
207 ipn.in_flags |= IPN_FILTER;
209 if (ipn.in_redir == NAT_REDIRECT) {
210 if (hostmask(&cpp, (u_32_t *)&ipn.in_srcip,
211 (u_32_t *)&ipn.in_srcmsk, &ipn.in_sport,
212 &ipn.in_scmp, &ipn.in_stop, linenum)) {
217 if (hostmask(&cpp, (u_32_t *)&ipn.in_inip,
218 (u_32_t *)&ipn.in_inmsk, &ipn.in_sport,
219 &ipn.in_scmp, &ipn.in_stop, linenum)) {
225 if (!strcmp(*cpp, "!")) {
227 ipn.in_flags |= IPN_NOTDST;
228 } else if (**cpp == '!') {
230 ipn.in_flags |= IPN_NOTDST;
233 if (strcasecmp(*cpp, "to")) {
234 fprintf(stderr, "%d: unexpected keyword (%s) - to\n",
239 if ((ipn.in_flags & IPN_NOTDST) &&
240 (ipn.in_redir & (NAT_REDIRECT))) {
241 fprintf(stderr, "Cannot use '! to' with rdr\n");
247 fprintf(stderr, "%d: missing host after to\n", linenum);
251 if (ipn.in_redir == NAT_REDIRECT) {
252 if (hostmask(&cpp, (u_32_t *)&ipn.in_outip,
253 (u_32_t *)&ipn.in_outmsk, &ipn.in_dport,
254 &ipn.in_dcmp, &ipn.in_dtop, linenum)) {
258 ipn.in_pmin = htons(ipn.in_dport);
260 if (hostmask(&cpp, (u_32_t *)&ipn.in_srcip,
261 (u_32_t *)&ipn.in_srcmsk, &ipn.in_dport,
262 &ipn.in_dcmp, &ipn.in_dtop, linenum)) {
270 fprintf(stderr, "%d: short line\n", linenum);
276 fprintf(stderr, "%d: no netmask on LHS\n", linenum);
281 if (ipn.in_redir == NAT_REDIRECT) {
282 if (hostnum((u_32_t *)&ipn.in_outip, s, linenum) == -1){
286 if (genmask(t, (u_32_t *)&ipn.in_outmsk) == -1) {
291 if (hostnum((u_32_t *)&ipn.in_inip, s, linenum) == -1) {
295 if (genmask(t, (u_32_t *)&ipn.in_inmsk) == -1) {
302 fprintf(stderr, "%d: short line\n", linenum);
309 * If it is a standard redirect then we expect it to have a port
310 * match after the hostmask.
312 if ((ipn.in_redir == NAT_REDIRECT) && !(ipn.in_flags & IPN_FILTER)) {
313 if (strcasecmp(*cpp, "port")) {
314 fprintf(stderr, "%d: missing fields - 1st port\n",
324 "%d: missing fields (destination port)\n",
330 if (isdigit(**cpp) && (s = strchr(*cpp, '-')))
337 if (!strcmp(*cpp, "-")) {
345 ipn.in_pmax = ipn.in_pmin;
349 * In the middle of the NAT rule syntax is -> to indicate the
350 * direction of translation.
353 fprintf(stderr, "%d: missing fields (->)\n", linenum);
357 if (strcmp(*cpp, "->")) {
358 fprintf(stderr, "%d: missing ->\n", linenum);
365 fprintf(stderr, "%d: missing fields (%s)\n",
366 linenum, ipn.in_redir ? "destination" : "target");
371 if (ipn.in_redir == NAT_MAP) {
372 if (!strcasecmp(*cpp, "range")) {
374 ipn.in_flags |= IPN_IPRANGE;
376 fprintf(stderr, "%d: missing fields (%s)\n",
378 ipn.in_redir ? "destination":"target");
385 if (ipn.in_flags & IPN_IPRANGE) {
386 dnetm = strrchr(*cpp, '-');
389 if (*cpp && !strcmp(*cpp, "-") && *(cpp + 1))
393 if (dnetm == NULL || *dnetm == '\0') {
395 "%d: desination range not specified\n",
400 } else if (ipn.in_redir != NAT_REDIRECT) {
401 dnetm = strrchr(*cpp, '/');
404 if (*cpp && !strcasecmp(*cpp, "netmask"))
409 "%d: missing fields (dest netmask)\n",
418 if (ipn.in_redir == NAT_REDIRECT) {
419 dnetm = strchr(*cpp, ',');
421 ipn.in_flags |= IPN_SPLIT;
424 if (hostnum((u_32_t *)&ipn.in_inip, *cpp, linenum) == -1) {
429 if (ntohl(ipn.in_inip) == INADDR_LOOPBACK) {
431 "localhost as destination not supported\n");
437 if (!strcmp(*cpp, ipn.in_ifname))
439 if (hostnum((u_32_t *)&ipn.in_outip, *cpp, linenum) == -1) {
446 if (ipn.in_redir & NAT_MAPBLK) {
448 if (strcasecmp(*cpp, "ports")) {
450 "%d: expected \"ports\" - got \"%s\"\n",
458 "%d: missing argument to \"ports\"\n",
463 if (!strcasecmp(*cpp, "auto"))
464 ipn.in_flags |= IPN_AUTOPORTMAP;
466 ipn.in_pmin = atoi(*cpp);
470 } else if ((ipn.in_redir & NAT_BIMAP) == NAT_REDIRECT) {
471 if (*cpp && (strrchr(*cpp, '/') != NULL)) {
472 fprintf(stderr, "%d: No netmask supported in %s\n",
473 linenum, "destination host for redirect");
479 fprintf(stderr, "%d: Missing destination port %s\n",
480 linenum, "in redirect");
485 /* If it's a in_redir, expect target port */
487 if (strcasecmp(*cpp, "port")) {
488 fprintf(stderr, "%d: missing fields - 2nd port (%s)\n",
496 "%d: missing fields (destination port)\n",
504 if (dnetm && *dnetm == '/')
507 if (ipn.in_redir & (NAT_MAP|NAT_MAPBLK)) {
508 if (ipn.in_flags & IPN_IPRANGE) {
509 if (hostnum((u_32_t *)&ipn.in_outmsk, dnetm,
514 } else if (genmask(dnetm, (u_32_t *)&ipn.in_outmsk)) {
519 if (ipn.in_flags & IPN_SPLIT) {
520 if (hostnum((u_32_t *)&ipn.in_inmsk, dnetm,
525 } else if (genmask("255.255.255.255", (u_32_t *)&ipn.in_inmsk)){
530 ipn.in_flags |= IPN_TCP; /* XXX- TCP only by default */
534 if (!strcasecmp(proto, "tcp"))
535 ipn.in_flags |= IPN_TCP;
536 else if (!strcasecmp(proto, "udp"))
537 ipn.in_flags |= IPN_UDP;
538 else if (!strcasecmp(proto, "tcp/udp"))
539 ipn.in_flags |= IPN_TCPUDP;
540 else if (!strcasecmp(proto, "tcpudp")) {
541 ipn.in_flags |= IPN_TCPUDP;
543 } else if (!strcasecmp(proto, "ip"))
544 ipn.in_flags |= IPN_ANY;
546 ipn.in_flags |= IPN_ANY;
547 if ((pr = getprotobyname(proto)))
548 ipn.in_p = pr->p_proto;
550 if (!isdigit(*proto)) {
552 "%d: Unknown protocol %s\n",
557 ipn.in_p = atoi(proto);
560 if ((ipn.in_flags & IPN_TCPUDP) == 0) {
565 if (*cpp && !strcasecmp(*cpp, "round-robin")) {
567 ipn.in_flags |= IPN_ROUNDR;
570 if (*cpp && !strcasecmp(*cpp, "frag")) {
572 ipn.in_flags |= IPN_FRAG;
575 if (*cpp && !strcasecmp(*cpp, "age")) {
579 "%d: age with no parameters\n",
585 ipn.in_age[0] = atoi(*cpp);
586 s = index(*cpp, '/');
588 ipn.in_age[1] = atoi(s + 1);
590 ipn.in_age[1] = ipn.in_age[0];
594 if (*cpp && !strcasecmp(*cpp, "mssclamp")) {
597 ipn.in_mssclamp = atoi(*cpp);
601 "%d: mssclamp with no parameters\n",
610 "%d: extra junk at the end of the line: %s\n",
618 if ((ipn.in_redir == NAT_REDIRECT) && !(ipn.in_flags & IPN_FILTER)) {
619 if (!portnum(port1a, &ipn.in_pmin, linenum)) {
623 ipn.in_pmin = htons(ipn.in_pmin);
624 if (port1b != NULL) {
625 if (!portnum(port1b, &ipn.in_pmax, linenum)) {
629 ipn.in_pmax = htons(ipn.in_pmax);
631 ipn.in_pmax = ipn.in_pmin;
634 if ((ipn.in_redir & NAT_BIMAP) == NAT_REDIRECT) {
635 if (!portnum(port2a, &ipn.in_pnext, linenum)) {
639 ipn.in_pnext = htons(ipn.in_pnext);
642 if (!(ipn.in_flags & IPN_SPLIT))
643 ipn.in_inip &= ipn.in_inmsk;
644 if ((ipn.in_flags & IPN_IPRANGE) == 0)
645 ipn.in_outip &= ipn.in_outmsk;
646 ipn.in_srcip &= ipn.in_srcmsk;
648 if ((ipn.in_redir & NAT_MAPBLK) != 0)
649 nat_setgroupmap(&ipn);
651 if (*cpp && !*(cpp+1) && !strcasecmp(*cpp, "frag")) {
653 ipn.in_flags |= IPN_FRAG;
661 if (ipn.in_redir != NAT_BIMAP && !strcasecmp(*cpp, "proxy")) {
664 if (ipn.in_redir == NAT_BIMAP) {
665 fprintf(stderr, "%d: cannot use proxy with bimap\n",
673 "%d: missing parameter for \"proxy\"\n",
680 if (!strcasecmp(*cpp, "port")) {
684 "%d: missing parameter for \"port\"\n",
695 "%d: missing parameter for \"proxy\"\n",
702 "%d: missing keyword \"port\"\n", linenum);
707 if ((proto = index(*cpp, '/'))) {
709 if ((pr = getprotobyname(proto)))
710 ipn.in_p = pr->p_proto;
712 ipn.in_p = atoi(proto);
716 if (dport && !portnum(dport, &pport, linenum))
718 if (ipn.in_dcmp != 0) {
719 if (pport != ipn.in_dport) {
721 "%d: mismatch in port numbers\n",
726 ipn.in_dport = htons(pport);
728 (void) strncpy(ipn.in_plabel, *cpp, sizeof(ipn.in_plabel));
731 } else if (ipn.in_redir != NAT_BIMAP && !strcasecmp(*cpp, "portmap")) {
732 if (ipn.in_redir == NAT_BIMAP) {
733 fprintf(stderr, "%d: cannot use portmap with bimap\n",
741 "%d: missing expression following portmap\n",
747 if (!strcasecmp(*cpp, "tcp"))
748 ipn.in_flags |= IPN_TCP;
749 else if (!strcasecmp(*cpp, "udp"))
750 ipn.in_flags |= IPN_UDP;
751 else if (!strcasecmp(*cpp, "tcpudp"))
752 ipn.in_flags |= IPN_TCPUDP;
753 else if (!strcasecmp(*cpp, "tcp/udp"))
754 ipn.in_flags |= IPN_TCPUDP;
757 "%d: expected protocol name - got \"%s\"\n",
766 fprintf(stderr, "%d: no port range found\n", linenum);
771 if (!strcasecmp(*cpp, "auto")) {
772 ipn.in_flags |= IPN_AUTOPORTMAP;
773 ipn.in_pmin = htons(1024);
774 ipn.in_pmax = htons(65535);
775 nat_setgroupmap(&ipn);
778 if (!(t = strchr(*cpp, ':'))) {
780 "%d: no port range in \"%s\"\n",
786 if (!portnum(*cpp, &ipn.in_pmin, linenum) ||
787 !portnum(t, &ipn.in_pmax, linenum)) {
791 ipn.in_pmin = htons(ipn.in_pmin);
792 ipn.in_pmax = htons(ipn.in_pmax);
797 if (*cpp && !strcasecmp(*cpp, "frag")) {
799 ipn.in_flags |= IPN_FRAG;
802 if (*cpp && !strcasecmp(*cpp, "age")) {
805 fprintf(stderr, "%d: age with no parameters\n",
810 ipn.in_age[0] = atoi(*cpp);
811 s = index(*cpp, '/');
813 ipn.in_age[1] = atoi(s + 1);
815 ipn.in_age[1] = ipn.in_age[0];
819 if (*cpp && !strcasecmp(*cpp, "mssclamp")) {
822 ipn.in_mssclamp = atoi(*cpp);
825 fprintf(stderr, "%d: mssclamp with no parameters\n",
833 fprintf(stderr, "%d: extra junk at the end of the line: %s\n",
844 void natparsefile(fd, file, opts)
855 if (strcmp(file, "-")) {
856 if (!(fp = fopen(file, "r"))) {
857 fprintf(stderr, "%s: open: %s\n", file,
864 while (fgets(line, sizeof(line) - 1, fp)) {
866 line[sizeof(line) - 1] = '\0';
867 if ((s = strchr(line, '\n')))
871 np = natparse(line, linenum, &parsestatus);
872 if (parsestatus != 0) {
874 fprintf(stderr, "%d: syntax error in \"%s\"\n",
877 fprintf(stderr, "%s: %s error (%d), quitting\n",
879 ((parsestatus < 0)? "parse": "internal"),
884 if ((opts & OPT_VERBOSE) && np)
886 if (!(opts & OPT_NODO)) {
887 if (!(opts & OPT_REMOVE)) {
888 if (ioctl(fd, SIOCADNAT, &np) == -1) {
889 fprintf(stderr, "%d:",
891 perror("ioctl(SIOCADNAT)");
893 } else if (ioctl(fd, SIOCRMNAT, &np) == -1) {
894 fprintf(stderr, "%d:", linenum);
895 perror("ioctl(SIOCRMNAT)");