1 /* vi: set sw=4 ts=4: */
4 * Similar to the standard Unix route, but with only the necessary
5 * parts for AF_INET and AF_INET6
7 * Bjorn Wesen, Axis Communications AB
9 * Author of the original route:
10 * Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
11 * (derived from FvK's 'route.c 1.70 01/04/94')
13 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
16 * displayroute() code added by Vladimir N. Oleynik <dzo@simtreas.ru>
17 * adjustments by Larry Doolittle <LRDoolittle@lbl.gov>
19 * IPV6 support added by Bart Visscher <magick@linux-fan.com>
22 /* 2004/03/09 Manuel Novoa III <mjn3@codepoet.org>
24 * Rewritten to fix several bugs, add additional error checking, and
25 * remove ridiculous amounts of bloat.
28 //usage:#define route_trivial_usage
29 //usage: "[{add|del|delete}]"
30 //usage:#define route_full_usage "\n\n"
31 //usage: "Edit kernel routing tables\n"
32 //usage: "\n -n Don't resolve names"
33 //usage: "\n -e Display other/more information"
34 //usage: "\n -A inet" IF_FEATURE_IPV6("{6}") " Select address family"
36 #include <net/route.h>
40 #include "inet_common.h"
44 /* Keep this in sync with /usr/src/linux/include/linux/route.h */
45 #define RTF_UP 0x0001 /* route usable */
46 #define RTF_GATEWAY 0x0002 /* destination is a gateway */
47 #define RTF_HOST 0x0004 /* host entry (net otherwise) */
48 #define RTF_REINSTATE 0x0008 /* reinstate route after tmout */
49 #define RTF_DYNAMIC 0x0010 /* created dyn. (by redirect) */
50 #define RTF_MODIFIED 0x0020 /* modified dyn. (by redirect) */
51 #define RTF_MTU 0x0040 /* specific MTU for this route */
53 #define RTF_MSS RTF_MTU /* Compatibility :-( */
55 #define RTF_WINDOW 0x0080 /* per route window clamping */
56 #define RTF_IRTT 0x0100 /* Initial round trip time */
57 #define RTF_REJECT 0x0200 /* Reject route */
60 #if defined(SIOCADDRTOLD) || defined(RTF_IRTT) /* route */
61 #define HAVE_NEW_ADDRT 1
65 #define mask_in_addr(x) (((struct sockaddr_in *)&((x).rt_genmask))->sin_addr.s_addr)
66 #define full_mask(x) (x)
68 #define mask_in_addr(x) ((x).rt_genmask)
69 #define full_mask(x) (((struct sockaddr_in *)&(x))->sin_addr.s_addr)
72 /* The RTACTION entries must agree with tbl_verb[] below! */
73 #define RTACTION_ADD 1
74 #define RTACTION_DEL 2
76 /* For the various tbl_*[] arrays, the 1st byte is the offset to
77 * the next entry and the 2nd byte is return value. */
82 /* We remap '-' to '#' to avoid problems with getopt. */
83 static const char tbl_hash_net_host[] ALIGN1 =
85 /* "\010\002#host\0" */
86 "\007\002#host" /* Since last, we can save a byte. */
89 #define KW_TAKES_ARG 020
90 #define KW_SETS_FLAG 040
92 #define KW_IPVx_METRIC 020
93 #define KW_IPVx_NETMASK 021
94 #define KW_IPVx_GATEWAY 022
95 #define KW_IPVx_MSS 023
96 #define KW_IPVx_WINDOW 024
97 #define KW_IPVx_IRTT 025
98 #define KW_IPVx_DEVICE 026
100 #define KW_IPVx_FLAG_ONLY 040
101 #define KW_IPVx_REJECT 040
102 #define KW_IPVx_MOD 041
103 #define KW_IPVx_DYN 042
104 #define KW_IPVx_REINSTATE 043
106 static const char tbl_ipvx[] ALIGN1 =
107 /* 020 is the "takes an arg" bit */
121 /* 040 is the "sets a flag" bit - MUST match flags_ipvx[] values below. */
127 /* "\014\043reinstate\0" */
128 "\013\043reinstate" /* Since last, we can save a byte. */
131 static const int flags_ipvx[] = { /* MUST match tbl_ipvx[] values above. */
140 static int kw_lookup(const char *kwtbl, char ***pargs)
144 if (strcmp(kwtbl+2, **pargs) == 0) { /* Found a match. */
146 if (kwtbl[1] & KW_TAKES_ARG) {
147 if (!**pargs) { /* No more args! */
150 *pargs += 1; /* Calling routine will use args[-1]. */
160 /* Add or delete a route, depending on action. */
162 static NOINLINE void INET_setroute(int action, char **args)
164 /* char buffer instead of bona-fide struct avoids aliasing warning */
165 char rt_buf[sizeof(struct rtentry)];
166 struct rtentry *const rt = (void *)rt_buf;
168 const char *netmask = NULL;
169 int skfd, isnet, xflag;
171 /* Grab the -net or -host options. Remember they were transformed. */
172 xflag = kw_lookup(tbl_hash_net_host, &args);
174 /* If we did grab -net or -host, make sure we still have an arg left. */
179 /* Clean out the RTREQ structure. */
180 memset(rt, 0, sizeof(*rt));
183 const char *target = *args++;
186 /* recognize x.x.x.x/mask format. */
187 prefix = strchr(target, '/');
191 prefix_len = xatoul_range(prefix+1, 0, 32);
192 mask_in_addr(*rt) = htonl( ~(0xffffffffUL >> prefix_len));
195 rt->rt_genmask.sa_family = AF_INET;
198 /* Default netmask. */
201 /* Prefer hostname lookup is -host flag (xflag==1) was given. */
202 isnet = INET_resolve(target, (struct sockaddr_in *) &rt->rt_dst,
203 (xflag & HOST_FLAG));
205 bb_error_msg_and_die("resolving %s", target);
208 /* do not destroy prefix for process args */
213 if (xflag) { /* Reinit isnet if -net or -host was specified. */
214 isnet = (xflag & NET_FLAG);
217 /* Fill in the other fields. */
218 rt->rt_flags = ((isnet) ? RTF_UP : (RTF_UP | RTF_HOST));
221 int k = kw_lookup(tbl_ipvx, &args);
222 const char *args_m1 = args[-1];
224 if (k & KW_IPVx_FLAG_ONLY) {
225 rt->rt_flags |= flags_ipvx[k & 3];
230 if (k == KW_IPVx_METRIC) {
231 rt->rt_metric = xatoul(args_m1) + 1;
236 if (k == KW_IPVx_NETMASK) {
237 struct sockaddr mask;
239 if (mask_in_addr(*rt)) {
244 isnet = INET_resolve(netmask, (struct sockaddr_in *) &mask, 0);
246 bb_error_msg_and_die("resolving %s", netmask);
248 rt->rt_genmask = full_mask(mask);
252 if (k == KW_IPVx_GATEWAY) {
253 if (rt->rt_flags & RTF_GATEWAY) {
257 isnet = INET_resolve(args_m1,
258 (struct sockaddr_in *) &rt->rt_gateway, 1);
259 rt->rt_flags |= RTF_GATEWAY;
263 bb_error_msg_and_die("resolving %s", args_m1);
265 bb_error_msg_and_die("gateway %s is a NETWORK", args_m1);
270 if (k == KW_IPVx_MSS) { /* Check valid MSS bounds. */
271 rt->rt_flags |= RTF_MSS;
272 rt->rt_mss = xatoul_range(args_m1, 64, 32768);
276 if (k == KW_IPVx_WINDOW) { /* Check valid window bounds. */
277 rt->rt_flags |= RTF_WINDOW;
278 rt->rt_window = xatoul_range(args_m1, 128, INT_MAX);
283 if (k == KW_IPVx_IRTT) {
284 rt->rt_flags |= RTF_IRTT;
285 rt->rt_irtt = xatoul(args_m1);
286 rt->rt_irtt *= (bb_clk_tck() / 100); /* FIXME */
287 #if 0 /* FIXME: do we need to check anything of this? */
288 if (rt->rt_irtt < 1 || rt->rt_irtt > (120 * HZ)) {
289 bb_error_msg_and_die("bad irtt");
296 /* Device is special in that it can be the last arg specified
297 * and doesn't requre the dev/device keyword in that case. */
298 if (!rt->rt_dev && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) {
299 /* Don't use args_m1 here since args may have changed! */
300 rt->rt_dev = args[-1];
304 /* Nothing matched. */
309 if ((rt->rt_flags & RTF_REJECT) && !rt->rt_dev) {
310 rt->rt_dev = (char*)"lo";
314 /* sanity checks.. */
315 if (mask_in_addr(*rt)) {
316 uint32_t mask = mask_in_addr(*rt);
319 if ((rt->rt_flags & RTF_HOST) && mask != 0xffffffff) {
320 bb_error_msg_and_die("netmask %.8x and host route conflict",
321 (unsigned int) mask);
323 if (mask & (mask + 1)) {
324 bb_error_msg_and_die("bogus netmask %s", netmask);
326 mask = ((struct sockaddr_in *) &rt->rt_dst)->sin_addr.s_addr;
327 if (mask & ~(uint32_t)mask_in_addr(*rt)) {
328 bb_error_msg_and_die("netmask and route address conflict");
332 /* Fill out netmask if still unset */
333 if ((action == RTACTION_ADD) && (rt->rt_flags & RTF_HOST)) {
334 mask_in_addr(*rt) = 0xffffffff;
337 /* Create a socket to the INET kernel. */
338 skfd = xsocket(AF_INET, SOCK_DGRAM, 0);
340 if (action == RTACTION_ADD)
341 xioctl(skfd, SIOCADDRT, rt);
343 xioctl(skfd, SIOCDELRT, rt);
345 if (ENABLE_FEATURE_CLEAN_UP) close(skfd);
348 #if ENABLE_FEATURE_IPV6
350 static NOINLINE void INET6_setroute(int action, char **args)
352 struct sockaddr_in6 sa6;
354 int prefix_len, skfd;
357 /* We know args isn't NULL from the check in route_main. */
358 const char *target = *args++;
360 if (strcmp(target, "default") == 0) {
362 memset(&sa6, 0, sizeof(sa6));
365 cp = strchr(target, '/'); /* Yes... const to non is ok. */
368 prefix_len = xatoul_range(cp + 1, 0, 128);
372 if (INET6_resolve(target, (struct sockaddr_in6 *) &sa6) < 0) {
373 bb_error_msg_and_die("resolving %s", target);
377 /* Clean out the RTREQ structure. */
378 memset(&rt, 0, sizeof(rt));
380 memcpy(&rt.rtmsg_dst, sa6.sin6_addr.s6_addr, sizeof(struct in6_addr));
382 /* Fill in the other fields. */
383 rt.rtmsg_dst_len = prefix_len;
384 rt.rtmsg_flags = ((prefix_len == 128) ? (RTF_UP|RTF_HOST) : RTF_UP);
390 int k = kw_lookup(tbl_ipvx, &args);
391 const char *args_m1 = args[-1];
393 if ((k == KW_IPVx_MOD) || (k == KW_IPVx_DYN)) {
394 rt.rtmsg_flags |= flags_ipvx[k & 3];
398 if (k == KW_IPVx_METRIC) {
399 rt.rtmsg_metric = xatoul(args_m1);
403 if (k == KW_IPVx_GATEWAY) {
404 if (rt.rtmsg_flags & RTF_GATEWAY) {
408 if (INET6_resolve(args_m1, (struct sockaddr_in6 *) &sa6) < 0) {
409 bb_error_msg_and_die("resolving %s", args_m1);
411 memcpy(&rt.rtmsg_gateway, sa6.sin6_addr.s6_addr,
412 sizeof(struct in6_addr));
413 rt.rtmsg_flags |= RTF_GATEWAY;
417 /* Device is special in that it can be the last arg specified
418 * and doesn't requre the dev/device keyword in that case. */
419 if (!devname && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) {
420 /* Don't use args_m1 here since args may have changed! */
425 /* Nothing matched. */
429 /* Create a socket to the INET6 kernel. */
430 skfd = xsocket(AF_INET6, SOCK_DGRAM, 0);
432 rt.rtmsg_ifindex = 0;
436 memset(&ifr, 0, sizeof(ifr));
437 strncpy_IFNAMSIZ(ifr.ifr_name, devname);
438 xioctl(skfd, SIOCGIFINDEX, &ifr);
439 rt.rtmsg_ifindex = ifr.ifr_ifindex;
442 /* Tell the kernel to accept this route. */
443 if (action == RTACTION_ADD)
444 xioctl(skfd, SIOCADDRT, &rt);
446 xioctl(skfd, SIOCDELRT, &rt);
448 if (ENABLE_FEATURE_CLEAN_UP) close(skfd);
452 static const unsigned flagvals[] = { /* Must agree with flagchars[]. */
458 #if ENABLE_FEATURE_IPV6
465 #define IPV4_MASK (RTF_GATEWAY|RTF_HOST|RTF_REINSTATE|RTF_DYNAMIC|RTF_MODIFIED)
466 #define IPV6_MASK (RTF_GATEWAY|RTF_HOST|RTF_DEFAULT|RTF_ADDRCONF|RTF_CACHE)
468 /* Must agree with flagvals[]. */
469 static const char flagchars[] ALIGN1 =
471 #if ENABLE_FEATURE_IPV6
476 static void set_flags(char *flagstr, int flags)
482 for (i = 0; (*flagstr = flagchars[i]) != 0; i++) {
483 if (flags & flagvals[i]) {
489 /* also used in netstat */
490 void FAST_FUNC bb_displayroutes(int noresolve, int netstatfmt)
492 char devname[64], flags[16], *sdest, *sgw;
493 unsigned long d, g, m;
494 int flgs, ref, use, metric, mtu, win, ir;
495 struct sockaddr_in s_addr;
498 FILE *fp = xfopen_for_read("/proc/net/route");
500 printf("Kernel IP routing table\n"
501 "Destination Gateway Genmask Flags %s Iface\n",
502 netstatfmt ? " MSS Window irtt" : "Metric Ref Use");
504 if (fscanf(fp, "%*[^\n]\n") < 0) { /* Skip the first line. */
505 goto ERROR; /* Empty or missing line, or read error. */
509 r = fscanf(fp, "%63s%lx%lx%X%d%d%d%lx%d%d%d\n",
510 devname, &d, &g, &flgs, &ref, &use, &metric, &m,
513 if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
517 bb_error_msg_and_die("fscanf");
520 if (!(flgs & RTF_UP)) { /* Skip interfaces that are down. */
524 set_flags(flags, (flgs & IPV4_MASK));
526 if (flgs & RTF_REJECT) {
531 memset(&s_addr, 0, sizeof(struct sockaddr_in));
532 s_addr.sin_family = AF_INET;
533 s_addr.sin_addr.s_addr = d;
534 sdest = INET_rresolve(&s_addr, (noresolve | 0x8000), m); /* 'default' instead of '*' */
535 s_addr.sin_addr.s_addr = g;
536 sgw = INET_rresolve(&s_addr, (noresolve | 0x4000), m); /* Host instead of net */
538 /* "%15.15s" truncates hostnames, do we really want that? */
539 printf("%-15.15s %-15.15s %-16s%-6s", sdest, sgw, inet_ntoa(mask), flags);
543 printf("%5d %-5d %6d %s\n", mtu, win, ir, devname);
545 printf("%-6d %-2d %7d %s\n", metric, ref, use, devname);
551 #if ENABLE_FEATURE_IPV6
553 static void INET6_displayroutes(void)
555 char addr6[128], *naddr6;
556 /* In addr6x, we store both 40-byte ':'-delimited ipv6 addresses.
557 * We read the non-delimited strings into the tail of the buffer
558 * using fscanf and then modify the buffer by shifting forward
559 * while inserting ':'s and the nul terminator for the first string.
560 * Hence the strings are at addr6x and addr6x+40. This generates
561 * _much_ less code than the previous (upstream) approach. */
563 char iface[16], flags[16];
564 int iflags, metric, refcnt, use, prefix_len, slen;
565 struct sockaddr_in6 snaddr6;
567 FILE *fp = xfopen_for_read("/proc/net/ipv6_route");
569 printf("Kernel IPv6 routing table\n%-44s%-40s"
570 "Flags Metric Ref Use Iface\n",
571 "Destination", "Next Hop");
575 r = fscanf(fp, "%32s%x%*s%x%32s%x%x%x%x%s\n",
576 addr6x+14, &prefix_len, &slen, addr6x+40+7,
577 &metric, &use, &refcnt, &iflags, iface);
579 if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
583 bb_error_msg_and_die("fscanf");
586 /* Do the addr6x shift-and-insert changes to ':'-delimit addresses.
587 * For now, always do this to validate the proc route format, even
588 * if the interface is down. */
595 if (i == 40) { /* nul terminator for 1st address? */
596 addr6x[39] = 0; /* Fixup... need 0 instead of ':'. */
597 ++p; /* Skip and continue. */
606 } while (i < 40+28+7);
609 if (!(iflags & RTF_UP)) { /* Skip interfaces that are down. */
613 set_flags(flags, (iflags & IPV6_MASK));
617 inet_pton(AF_INET6, addr6x + r,
618 (struct sockaddr *) &snaddr6.sin6_addr);
619 snaddr6.sin6_family = AF_INET6;
620 naddr6 = INET6_rresolve((struct sockaddr_in6 *) &snaddr6,
621 0x0fff /* Apparently, upstream never resolves. */
624 if (!r) { /* 1st pass */
625 snprintf(addr6, sizeof(addr6), "%s/%d", naddr6, prefix_len);
628 } else { /* 2nd pass */
629 /* Print the info. */
630 printf("%-43s %-39s %-5s %-6d %-2d %7d %-8s\n",
631 addr6, naddr6, flags, metric, refcnt, use, iface);
642 #define ROUTE_OPT_A 0x01
643 #define ROUTE_OPT_n 0x02
644 #define ROUTE_OPT_e 0x04
645 #define ROUTE_OPT_INET6 0x08 /* Not an actual option. See below. */
647 /* 1st byte is offset to next entry offset. 2nd byte is return value. */
648 /* 2nd byte matches RTACTION_* code */
649 static const char tbl_verb[] ALIGN1 =
652 /* "\011\002delete\0" */
653 "\010\002delete" /* Since it's last, we can save a byte. */
656 int route_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
657 int route_main(int argc UNUSED_PARAM, char **argv)
664 /* First, remap '-net' and '-host' to avoid getopt problems. */
667 if (strcmp(*p, "-net") == 0 || strcmp(*p, "-host") == 0) {
672 opt = getopt32(argv, "A:ne", &family);
674 if ((opt & ROUTE_OPT_A) && strcmp(family, "inet") != 0) {
675 #if ENABLE_FEATURE_IPV6
676 if (strcmp(family, "inet6") == 0) {
677 opt |= ROUTE_OPT_INET6; /* Set flag for ipv6. */
685 /* No more args means display the routing table. */
687 int noresolve = (opt & ROUTE_OPT_n) ? 0x0fff : 0;
688 #if ENABLE_FEATURE_IPV6
689 if (opt & ROUTE_OPT_INET6)
690 INET6_displayroutes();
693 bb_displayroutes(noresolve, opt & ROUTE_OPT_e);
695 fflush_stdout_and_exit(EXIT_SUCCESS);
698 /* Check verb. At the moment, must be add, del, or delete. */
699 what = kw_lookup(tbl_verb, &argv);
700 if (!what || !*argv) { /* Unknown verb or no more args. */
704 #if ENABLE_FEATURE_IPV6
705 if (opt & ROUTE_OPT_INET6)
706 INET6_setroute(what, argv);
709 INET_setroute(what, argv);