3 * Similar to the standard Unix route, but with only the necessary
4 * parts for AF_INET and AF_INET6
6 * Bjorn Wesen, Axis Communications AB
8 * Author of the original route:
9 * Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
10 * (derived from FvK's 'route.c 1.70 01/04/94')
12 * This program is free software; you can redistribute it
13 * and/or modify it under the terms of the GNU General
14 * Public License as published by the Free Software
15 * Foundation; either version 2 of the License, or (at
16 * your option) any later version.
18 * $Id: route.c,v 1.26 2004/03/19 23:27:08 mjn3 Exp $
20 * displayroute() code added by Vladimir N. Oleynik <dzo@simtreas.ru>
21 * adjustments by Larry Doolittle <LRDoolittle@lbl.gov>
23 * IPV6 support added by Bart Visscher <magick@linux-fan.com>
26 /* 2004/03/09 Manuel Novoa III <mjn3@codepoet.org>
28 * Rewritten to fix several bugs, add additional error checking, and
29 * remove ridiculous amounts of bloat.
40 #include <sys/types.h>
41 #include <sys/ioctl.h>
42 #include <net/route.h>
45 #include "inet_common.h"
48 /* Keep this in sync with /usr/src/linux/include/linux/route.h */
49 #define RTF_UP 0x0001 /* route usable */
50 #define RTF_GATEWAY 0x0002 /* destination is a gateway */
51 #define RTF_HOST 0x0004 /* host entry (net otherwise) */
52 #define RTF_REINSTATE 0x0008 /* reinstate route after tmout */
53 #define RTF_DYNAMIC 0x0010 /* created dyn. (by redirect) */
54 #define RTF_MODIFIED 0x0020 /* modified dyn. (by redirect) */
55 #define RTF_MTU 0x0040 /* specific MTU for this route */
57 #define RTF_MSS RTF_MTU /* Compatibility :-( */
59 #define RTF_WINDOW 0x0080 /* per route window clamping */
60 #define RTF_IRTT 0x0100 /* Initial round trip time */
61 #define RTF_REJECT 0x0200 /* Reject route */
64 #if defined (SIOCADDRTOLD) || defined (RTF_IRTT) /* route */
65 #define HAVE_NEW_ADDRT 1
69 #define mask_in_addr(x) (((struct sockaddr_in *)&((x).rt_genmask))->sin_addr.s_addr)
70 #define full_mask(x) (x)
72 #define mask_in_addr(x) ((x).rt_genmask)
73 #define full_mask(x) (((struct sockaddr_in *)&(x))->sin_addr.s_addr)
76 /* The RTACTION entries must agree with tbl_verb[] below! */
77 #define RTACTION_ADD 1
78 #define RTACTION_DEL 2
80 /* For the various tbl_*[] arrays, the 1st byte is the offset to
81 * the next entry and the 2nd byte is return value. */
86 /* We remap '-' to '#' to avoid problems with getopt. */
87 static const char tbl_hash_net_host[] =
89 /* "\010\002#host\0" */
90 "\007\002#host" /* Since last, we can save a byte. */
93 #define KW_TAKES_ARG 020
94 #define KW_SETS_FLAG 040
96 #define KW_IPVx_METRIC 020
97 #define KW_IPVx_NETMASK 021
98 #define KW_IPVx_GATEWAY 022
99 #define KW_IPVx_MSS 023
100 #define KW_IPVx_WINDOW 024
101 #define KW_IPVx_IRTT 025
102 #define KW_IPVx_DEVICE 026
104 #define KW_IPVx_FLAG_ONLY 040
105 #define KW_IPVx_REJECT 040
106 #define KW_IPVx_MOD 041
107 #define KW_IPVx_DYN 042
108 #define KW_IPVx_REINSTATE 043
110 static const char tbl_ipvx[] =
111 /* 020 is the "takes an arg" bit */
125 /* 040 is the "sets a flag" bit - MUST match flags_ipvx[] values below. */
131 /* "\014\043reinstate\0" */
132 "\013\043reinstate" /* Since last, we can save a byte. */
135 static const int flags_ipvx[] = { /* MUST match tbl_ipvx[] values above. */
144 static int kw_lookup(const char *kwtbl, char ***pargs)
148 if (strcmp(kwtbl+2, **pargs) == 0) { /* Found a match. */
150 if (kwtbl[1] & KW_TAKES_ARG) {
151 if (!**pargs) { /* No more args! */
154 *pargs += 1; /* Calling routine will use args[-1]. */
164 /* Add or delete a route, depending on action. */
166 static void INET_setroute(int action, char **args)
170 int skfd, isnet, xflag;
172 assert((action == RTACTION_ADD) || (action == RTACTION_DEL));
174 /* Grab the -net or -host options. Remember they were transformed. */
175 xflag = kw_lookup(tbl_hash_net_host, &args);
177 /* If we did grab -net or -host, make sure we still have an arg left. */
182 /* Clean out the RTREQ structure. */
183 memset((char *) &rt, 0, sizeof(struct rtentry));
186 const char *target = *args++;
188 /* Prefer hostname lookup is -host flag (xflag==1) was given. */
189 isnet = INET_resolve(target, (struct sockaddr_in *) &rt.rt_dst,
190 (xflag & HOST_FLAG));
192 bb_error_msg_and_die("resolving %s", target);
197 if (xflag) { /* Reinit isnet if -net or -host was specified. */
198 isnet = (xflag & NET_FLAG);
201 /* Fill in the other fields. */
202 rt.rt_flags = ((isnet) ? RTF_UP : (RTF_UP | RTF_HOST));
204 netmask = bb_INET_default;
207 int k = kw_lookup(tbl_ipvx, &args);
208 const char *args_m1 = args[-1];
210 if (k & KW_IPVx_FLAG_ONLY) {
211 rt.rt_flags |= flags_ipvx[k & 3];
216 if (k == KW_IPVx_METRIC) {
217 rt.rt_metric = bb_xgetularg10(args_m1) + 1;
222 if (k == KW_IPVx_NETMASK) {
223 struct sockaddr mask;
225 if (mask_in_addr(rt)) {
230 isnet = INET_resolve(netmask, (struct sockaddr_in *) &mask, 0);
232 bb_error_msg_and_die("resolving %s", netmask);
234 rt.rt_genmask = full_mask(mask);
238 if (k == KW_IPVx_GATEWAY) {
239 if (rt.rt_flags & RTF_GATEWAY) {
243 isnet = INET_resolve(args_m1,
244 (struct sockaddr_in *) &rt.rt_gateway, 1);
245 rt.rt_flags |= RTF_GATEWAY;
249 bb_error_msg_and_die("resolving %s", args_m1);
251 bb_error_msg_and_die("gateway %s is a NETWORK", args_m1);
256 if (k == KW_IPVx_MSS) { /* Check valid MSS bounds. */
257 rt.rt_flags |= RTF_MSS;
258 rt.rt_mss = bb_xgetularg10_bnd(args_m1, 64, 32768);
262 if (k == KW_IPVx_WINDOW) { /* Check valid window bounds. */
263 rt.rt_flags |= RTF_WINDOW;
264 rt.rt_window = bb_xgetularg10_bnd(args_m1, 128, INT_MAX);
269 if (k == KW_IPVx_IRTT) {
270 rt.rt_flags |= RTF_IRTT;
271 rt.rt_irtt = bb_xgetularg10(args_m1);
272 rt.rt_irtt *= (sysconf(_SC_CLK_TCK) / 100); /* FIXME */
273 #if 0 /* FIXME: do we need to check anything of this? */
274 if (rt.rt_irtt < 1 || rt.rt_irtt > (120 * HZ)) {
275 bb_error_msg_and_die("bad irtt");
282 /* Device is special in that it can be the last arg specified
283 * and doesn't requre the dev/device keyword in that case. */
284 if (!rt.rt_dev && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) {
285 /* Don't use args_m1 here since args may have changed! */
286 rt.rt_dev = args[-1];
290 /* Nothing matched. */
295 if ((rt.rt_flags & RTF_REJECT) && !rt.rt_dev) {
300 /* sanity checks.. */
301 if (mask_in_addr(rt)) {
302 unsigned long mask = mask_in_addr(rt);
305 if ((rt.rt_flags & RTF_HOST) && mask != 0xffffffff) {
306 bb_error_msg_and_die("netmask %.8x and host route conflict",
307 (unsigned int) mask);
309 if (mask & (mask + 1)) {
310 bb_error_msg_and_die("bogus netmask %s", netmask);
312 mask = ((struct sockaddr_in *) &rt.rt_dst)->sin_addr.s_addr;
313 if (mask & ~mask_in_addr(rt)) {
314 bb_error_msg_and_die("netmask and route address conflict");
318 /* Fill out netmask if still unset */
319 if ((action == RTACTION_ADD) && (rt.rt_flags & RTF_HOST)) {
320 mask_in_addr(rt) = 0xffffffff;
323 /* Create a socket to the INET kernel. */
324 if ((skfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
325 bb_perror_msg_and_die("socket");
328 if (ioctl(skfd, ((action==RTACTION_ADD) ? SIOCADDRT : SIOCDELRT), &rt)<0) {
329 bb_perror_msg_and_die("SIOC[ADD|DEL]RT");
332 /* Don't bother closing, as we're exiting after we return anyway. */
336 #ifdef CONFIG_FEATURE_IPV6
338 static void INET6_setroute(int action, char **args)
340 struct sockaddr_in6 sa6;
342 int prefix_len, skfd;
345 assert((action == RTACTION_ADD) || (action == RTACTION_DEL));
348 /* We know args isn't NULL from the check in route_main. */
349 const char *target = *args++;
351 if (strcmp(target, "default") == 0) {
353 memset(&sa6, 0, sizeof(sa6));
356 if ((cp = strchr(target, '/'))) { /* Yes... const to non is ok. */
358 prefix_len = bb_xgetularg10_bnd(cp+1, 0, 128);
362 if (INET6_resolve(target, (struct sockaddr_in6 *) &sa6) < 0) {
363 bb_error_msg_and_die("resolving %s", target);
368 /* Clean out the RTREQ structure. */
369 memset((char *) &rt, 0, sizeof(struct in6_rtmsg));
371 memcpy(&rt.rtmsg_dst, sa6.sin6_addr.s6_addr, sizeof(struct in6_addr));
373 /* Fill in the other fields. */
374 rt.rtmsg_dst_len = prefix_len;
375 rt.rtmsg_flags = ((prefix_len == 128) ? (RTF_UP|RTF_HOST) : RTF_UP);
381 int k = kw_lookup(tbl_ipvx, &args);
382 const char *args_m1 = args[-1];
384 if ((k == KW_IPVx_MOD) || (k == KW_IPVx_DYN)) {
385 rt.rtmsg_flags |= flags_ipvx[k & 3];
389 if (k == KW_IPVx_METRIC) {
390 rt.rtmsg_metric = bb_xgetularg10(args_m1);
394 if (k == KW_IPVx_GATEWAY) {
395 if (rt.rtmsg_flags & RTF_GATEWAY) {
399 if (INET6_resolve(args_m1, (struct sockaddr_in6 *) &sa6) < 0) {
400 bb_error_msg_and_die("resolving %s", args_m1);
402 memcpy(&rt.rtmsg_gateway, sa6.sin6_addr.s6_addr,
403 sizeof(struct in6_addr));
404 rt.rtmsg_flags |= RTF_GATEWAY;
408 /* Device is special in that it can be the last arg specified
409 * and doesn't requre the dev/device keyword in that case. */
410 if (!devname && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) {
411 /* Don't use args_m1 here since args may have changed! */
416 /* Nothing matched. */
420 /* Create a socket to the INET6 kernel. */
421 if ((skfd = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
422 bb_perror_msg_and_die("socket");
425 rt.rtmsg_ifindex = 0;
429 memset(&ifr, 0, sizeof(ifr));
430 strcpy(ifr.ifr_name, devname);
432 if (ioctl(skfd, SIOGIFINDEX, &ifr) < 0) {
433 bb_perror_msg_and_die("SIOGIFINDEX");
435 rt.rtmsg_ifindex = ifr.ifr_ifindex;
438 /* Tell the kernel to accept this route. */
439 if (ioctl(skfd, ((action==RTACTION_ADD) ? SIOCADDRT : SIOCDELRT), &rt)<0) {
440 bb_perror_msg_and_die("SIOC[ADD|DEL]RT");
443 /* Don't bother closing, as we're exiting after we return anyway. */
448 static const unsigned int flagvals[] = { /* Must agree with flagchars[]. */
454 #ifdef CONFIG_FEATURE_IPV6
461 #define IPV4_MASK (RTF_GATEWAY|RTF_HOST|RTF_REINSTATE|RTF_DYNAMIC|RTF_MODIFIED)
462 #define IPV6_MASK (RTF_GATEWAY|RTF_HOST|RTF_DEFAULT|RTF_ADDRCONF|RTF_CACHE)
464 static const char flagchars[] = /* Must agree with flagvals[]. */
466 #ifdef CONFIG_FEATURE_IPV6
472 #ifndef CONFIG_FEATURE_IPV6
475 void set_flags(char *flagstr, int flags)
481 for (i=0 ; (*flagstr = flagchars[i]) != 0 ; i++) {
482 if (flags & flagvals[i]) {
488 void displayroutes(int noresolve, int netstatfmt)
490 char devname[64], flags[16], sdest[16], sgw[16];
491 unsigned long int d, g, m;
492 int flgs, ref, use, metric, mtu, win, ir;
493 struct sockaddr_in s_addr;
496 FILE *fp = bb_xfopen("/proc/net/route", "r");
498 bb_printf("Kernel IP routing table\n"
499 "Destination Gateway Genmask"
501 netstatfmt ? " MSS Window irtt" : "Metric Ref Use");
503 if (fscanf(fp, "%*[^\n]\n") < 0) { /* Skip the first line. */
504 goto ERROR; /* Empty or missing line, or read error. */
508 r = fscanf(fp, "%63s%lx%lx%X%d%d%d%lx%d%d%d\n",
509 devname, &d, &g, &flgs, &ref, &use, &metric, &m,
512 if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
516 bb_error_msg_and_die("fscanf");
519 if (!(flgs & RTF_UP)) { /* Skip interfaces that are down. */
523 set_flags(flags, (flgs & IPV4_MASK));
525 if (flgs & RTF_REJECT) {
530 memset(&s_addr, 0, sizeof(struct sockaddr_in));
531 s_addr.sin_family = AF_INET;
532 s_addr.sin_addr.s_addr = d;
533 INET_rresolve(sdest, sizeof(sdest), &s_addr,
534 (noresolve | 0x8000), m); /* Default instead of *. */
536 s_addr.sin_addr.s_addr = g;
537 INET_rresolve(sgw, sizeof(sgw), &s_addr,
538 (noresolve | 0x4000), m); /* Host instead of net. */
541 bb_printf("%-16s%-16s%-16s%-6s", sdest, sgw, inet_ntoa(mask), flags);
543 bb_printf("%5d %-5d %6d %s\n", mtu, win, ir, devname);
545 bb_printf("%-6d %-2d %7d %s\n", metric, ref, use, devname);
550 #ifdef CONFIG_FEATURE_IPV6
552 static void INET6_displayroutes(int noresolve)
554 char addr6[128], naddr6[128];
555 /* In addr6x, we store both 40-byte ':'-delimited ipv6 addresses.
556 * We read the non-delimited strings into the tail of the buffer
557 * using fscanf and then modify the buffer by shifting forward
558 * while inserting ':'s and the nul terminator for the first string.
559 * Hence the strings are at addr6x and addr6x+40. This generates
560 * _much_ less code than the previous (upstream) approach. */
562 char iface[16], flags[16];
563 int iflags, metric, refcnt, use, prefix_len, slen;
564 struct sockaddr_in6 snaddr6;
566 FILE *fp = bb_xfopen("/proc/net/ipv6_route", "r");
568 bb_printf("Kernel IPv6 routing table\n%-44s%-40s"
569 "Flags Metric Ref Use Iface\n",
570 "Destination", "Next Hop");
574 r = fscanf(fp, "%32s%x%*s%x%32s%x%x%x%x%s\n",
575 addr6x+14, &prefix_len, &slen, addr6x+40+7,
576 &metric, &use, &refcnt, &iflags, iface);
578 if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
582 bb_error_msg_and_die("fscanf");
585 /* Do the addr6x shift-and-insert changes to ':'-delimit addresses.
586 * For now, always do this to validate the proc route format, even
587 * if the interface is down. */
594 if (i==40) { /* nul terminator for 1st address? */
595 addr6x[39] = 0; /* Fixup... need 0 instead of ':'. */
596 ++p; /* Skip and continue. */
605 } while (i < 40+28+7);
608 if (!(iflags & RTF_UP)) { /* Skip interfaces that are down. */
612 set_flags(flags, (iflags & IPV6_MASK));
616 inet_pton(AF_INET6, addr6x + r,
617 (struct sockaddr *) &snaddr6.sin6_addr);
618 snaddr6.sin6_family = AF_INET6;
619 INET6_rresolve(naddr6, sizeof(naddr6),
620 (struct sockaddr_in6 *) &snaddr6,
622 (noresolve | 0x8000) /* Default instead of *. */
624 0x0fff /* Apparently, upstream never resolves. */
628 if (!r) { /* 1st pass */
629 snprintf(addr6, sizeof(addr6), "%s/%d", naddr6, prefix_len);
631 } else { /* 2nd pass */
632 /* Print the info. */
633 bb_printf("%-43s %-39s %-5s %-6d %-2d %7d %-8s\n",
634 addr6, naddr6, flags, metric, refcnt, use, iface);
643 #define ROUTE_OPT_A 0x01
644 #define ROUTE_OPT_n 0x02
645 #define ROUTE_OPT_e 0x04
646 #define ROUTE_OPT_INET6 0x08 /* Not an actual option. See below. */
648 /* 1st byte is offset to next entry offset. 2nd byte is return value. */
649 static const char tbl_verb[] = /* 2nd byte matches RTACTION_* code */
652 /* "\011\002delete\0" */
653 "\010\002delete" /* Since last, we can save a byte. */
656 int route_main(int argc, char **argv)
662 /* First, remap '-net' and '-host' to avoid getopt problems. */
667 if ((strcmp(*p, "-net") == 0) || (strcmp(*p, "-host") == 0)) {
673 opt = bb_getopt_ulflags(argc, argv, "A:ne", &family);
675 if ((opt & ROUTE_OPT_A) && strcmp(family, "inet")) {
676 #ifdef CONFIG_FEATURE_IPV6
677 if (strcmp(family, "inet6") == 0) {
678 opt |= ROUTE_OPT_INET6; /* Set flag for ipv6. */
686 /* No more args means display the routing table. */
688 int noresolve = (opt & ROUTE_OPT_n) ? 0x0fff : 0;
689 #ifdef CONFIG_FEATURE_IPV6
690 if (opt & ROUTE_OPT_INET6)
691 INET6_displayroutes(noresolve);
694 displayroutes(noresolve, opt & ROUTE_OPT_e);
697 bb_fflush_stdout_and_exit(EXIT_SUCCESS);
700 /* Check verb. At the moment, must be add, del, or delete. */
701 what = kw_lookup(tbl_verb, &argv);
702 if (!what || !*argv) { /* Unknown verb or no more args. */
706 #ifdef CONFIG_FEATURE_IPV6
707 if (opt & ROUTE_OPT_INET6)
708 INET6_setroute(what, argv);
711 INET_setroute(what, argv);