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 #include <net/route.h>
32 #include "inet_common.h"
36 /* Keep this in sync with /usr/src/linux/include/linux/route.h */
37 #define RTF_UP 0x0001 /* route usable */
38 #define RTF_GATEWAY 0x0002 /* destination is a gateway */
39 #define RTF_HOST 0x0004 /* host entry (net otherwise) */
40 #define RTF_REINSTATE 0x0008 /* reinstate route after tmout */
41 #define RTF_DYNAMIC 0x0010 /* created dyn. (by redirect) */
42 #define RTF_MODIFIED 0x0020 /* modified dyn. (by redirect) */
43 #define RTF_MTU 0x0040 /* specific MTU for this route */
45 #define RTF_MSS RTF_MTU /* Compatibility :-( */
47 #define RTF_WINDOW 0x0080 /* per route window clamping */
48 #define RTF_IRTT 0x0100 /* Initial round trip time */
49 #define RTF_REJECT 0x0200 /* Reject route */
52 #if defined(SIOCADDRTOLD) || defined(RTF_IRTT) /* route */
53 #define HAVE_NEW_ADDRT 1
57 #define mask_in_addr(x) (((struct sockaddr_in *)&((x).rt_genmask))->sin_addr.s_addr)
58 #define full_mask(x) (x)
60 #define mask_in_addr(x) ((x).rt_genmask)
61 #define full_mask(x) (((struct sockaddr_in *)&(x))->sin_addr.s_addr)
64 /* The RTACTION entries must agree with tbl_verb[] below! */
65 #define RTACTION_ADD 1
66 #define RTACTION_DEL 2
68 /* For the various tbl_*[] arrays, the 1st byte is the offset to
69 * the next entry and the 2nd byte is return value. */
74 /* We remap '-' to '#' to avoid problems with getopt. */
75 static const char tbl_hash_net_host[] ALIGN1 =
77 /* "\010\002#host\0" */
78 "\007\002#host" /* Since last, we can save a byte. */
81 #define KW_TAKES_ARG 020
82 #define KW_SETS_FLAG 040
84 #define KW_IPVx_METRIC 020
85 #define KW_IPVx_NETMASK 021
86 #define KW_IPVx_GATEWAY 022
87 #define KW_IPVx_MSS 023
88 #define KW_IPVx_WINDOW 024
89 #define KW_IPVx_IRTT 025
90 #define KW_IPVx_DEVICE 026
92 #define KW_IPVx_FLAG_ONLY 040
93 #define KW_IPVx_REJECT 040
94 #define KW_IPVx_MOD 041
95 #define KW_IPVx_DYN 042
96 #define KW_IPVx_REINSTATE 043
98 static const char tbl_ipvx[] ALIGN1 =
99 /* 020 is the "takes an arg" bit */
113 /* 040 is the "sets a flag" bit - MUST match flags_ipvx[] values below. */
119 /* "\014\043reinstate\0" */
120 "\013\043reinstate" /* Since last, we can save a byte. */
123 static const int flags_ipvx[] = { /* MUST match tbl_ipvx[] values above. */
132 static int kw_lookup(const char *kwtbl, char ***pargs)
136 if (strcmp(kwtbl+2, **pargs) == 0) { /* Found a match. */
138 if (kwtbl[1] & KW_TAKES_ARG) {
139 if (!**pargs) { /* No more args! */
142 *pargs += 1; /* Calling routine will use args[-1]. */
152 /* Add or delete a route, depending on action. */
154 static NOINLINE void INET_setroute(int action, char **args)
156 /* char buffer instead of bona-fide struct avoids aliasing warning */
157 char rt_buf[sizeof(struct rtentry)];
158 struct rtentry *const rt = (void *)rt_buf;
160 const char *netmask = NULL;
161 int skfd, isnet, xflag;
163 /* Grab the -net or -host options. Remember they were transformed. */
164 xflag = kw_lookup(tbl_hash_net_host, &args);
166 /* If we did grab -net or -host, make sure we still have an arg left. */
171 /* Clean out the RTREQ structure. */
172 memset(rt, 0, sizeof(*rt));
175 const char *target = *args++;
178 /* recognize x.x.x.x/mask format. */
179 prefix = strchr(target, '/');
183 prefix_len = xatoul_range(prefix+1, 0, 32);
184 mask_in_addr(*rt) = htonl( ~(0xffffffffUL >> prefix_len));
187 rt->rt_genmask.sa_family = AF_INET;
190 /* Default netmask. */
193 /* Prefer hostname lookup is -host flag (xflag==1) was given. */
194 isnet = INET_resolve(target, (struct sockaddr_in *) &rt->rt_dst,
195 (xflag & HOST_FLAG));
197 bb_error_msg_and_die("resolving %s", target);
200 /* do not destroy prefix for process args */
205 if (xflag) { /* Reinit isnet if -net or -host was specified. */
206 isnet = (xflag & NET_FLAG);
209 /* Fill in the other fields. */
210 rt->rt_flags = ((isnet) ? RTF_UP : (RTF_UP | RTF_HOST));
213 int k = kw_lookup(tbl_ipvx, &args);
214 const char *args_m1 = args[-1];
216 if (k & KW_IPVx_FLAG_ONLY) {
217 rt->rt_flags |= flags_ipvx[k & 3];
222 if (k == KW_IPVx_METRIC) {
223 rt->rt_metric = xatoul(args_m1) + 1;
228 if (k == KW_IPVx_NETMASK) {
229 struct sockaddr mask;
231 if (mask_in_addr(*rt)) {
236 isnet = INET_resolve(netmask, (struct sockaddr_in *) &mask, 0);
238 bb_error_msg_and_die("resolving %s", netmask);
240 rt->rt_genmask = full_mask(mask);
244 if (k == KW_IPVx_GATEWAY) {
245 if (rt->rt_flags & RTF_GATEWAY) {
249 isnet = INET_resolve(args_m1,
250 (struct sockaddr_in *) &rt->rt_gateway, 1);
251 rt->rt_flags |= RTF_GATEWAY;
255 bb_error_msg_and_die("resolving %s", args_m1);
257 bb_error_msg_and_die("gateway %s is a NETWORK", args_m1);
262 if (k == KW_IPVx_MSS) { /* Check valid MSS bounds. */
263 rt->rt_flags |= RTF_MSS;
264 rt->rt_mss = xatoul_range(args_m1, 64, 32768);
268 if (k == KW_IPVx_WINDOW) { /* Check valid window bounds. */
269 rt->rt_flags |= RTF_WINDOW;
270 rt->rt_window = xatoul_range(args_m1, 128, INT_MAX);
275 if (k == KW_IPVx_IRTT) {
276 rt->rt_flags |= RTF_IRTT;
277 rt->rt_irtt = xatoul(args_m1);
278 rt->rt_irtt *= (sysconf(_SC_CLK_TCK) / 100); /* FIXME */
279 #if 0 /* FIXME: do we need to check anything of this? */
280 if (rt->rt_irtt < 1 || rt->rt_irtt > (120 * HZ)) {
281 bb_error_msg_and_die("bad irtt");
288 /* Device is special in that it can be the last arg specified
289 * and doesn't requre the dev/device keyword in that case. */
290 if (!rt->rt_dev && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) {
291 /* Don't use args_m1 here since args may have changed! */
292 rt->rt_dev = args[-1];
296 /* Nothing matched. */
301 if ((rt->rt_flags & RTF_REJECT) && !rt->rt_dev) {
302 rt->rt_dev = (char*)"lo";
306 /* sanity checks.. */
307 if (mask_in_addr(*rt)) {
308 uint32_t mask = mask_in_addr(*rt);
311 if ((rt->rt_flags & RTF_HOST) && mask != 0xffffffff) {
312 bb_error_msg_and_die("netmask %.8x and host route conflict",
313 (unsigned int) mask);
315 if (mask & (mask + 1)) {
316 bb_error_msg_and_die("bogus netmask %s", netmask);
318 mask = ((struct sockaddr_in *) &rt->rt_dst)->sin_addr.s_addr;
319 if (mask & ~(uint32_t)mask_in_addr(*rt)) {
320 bb_error_msg_and_die("netmask and route address conflict");
324 /* Fill out netmask if still unset */
325 if ((action == RTACTION_ADD) && (rt->rt_flags & RTF_HOST)) {
326 mask_in_addr(*rt) = 0xffffffff;
329 /* Create a socket to the INET kernel. */
330 skfd = xsocket(AF_INET, SOCK_DGRAM, 0);
332 if (action == RTACTION_ADD)
333 xioctl(skfd, SIOCADDRT, rt);
335 xioctl(skfd, SIOCDELRT, rt);
337 if (ENABLE_FEATURE_CLEAN_UP) close(skfd);
340 #if ENABLE_FEATURE_IPV6
342 static NOINLINE void INET6_setroute(int action, char **args)
344 struct sockaddr_in6 sa6;
346 int prefix_len, skfd;
349 /* We know args isn't NULL from the check in route_main. */
350 const char *target = *args++;
352 if (strcmp(target, "default") == 0) {
354 memset(&sa6, 0, sizeof(sa6));
357 cp = strchr(target, '/'); /* Yes... const to non is ok. */
360 prefix_len = xatoul_range(cp + 1, 0, 128);
364 if (INET6_resolve(target, (struct sockaddr_in6 *) &sa6) < 0) {
365 bb_error_msg_and_die("resolving %s", target);
369 /* Clean out the RTREQ structure. */
370 memset(&rt, 0, sizeof(rt));
372 memcpy(&rt.rtmsg_dst, sa6.sin6_addr.s6_addr, sizeof(struct in6_addr));
374 /* Fill in the other fields. */
375 rt.rtmsg_dst_len = prefix_len;
376 rt.rtmsg_flags = ((prefix_len == 128) ? (RTF_UP|RTF_HOST) : RTF_UP);
382 int k = kw_lookup(tbl_ipvx, &args);
383 const char *args_m1 = args[-1];
385 if ((k == KW_IPVx_MOD) || (k == KW_IPVx_DYN)) {
386 rt.rtmsg_flags |= flags_ipvx[k & 3];
390 if (k == KW_IPVx_METRIC) {
391 rt.rtmsg_metric = xatoul(args_m1);
395 if (k == KW_IPVx_GATEWAY) {
396 if (rt.rtmsg_flags & RTF_GATEWAY) {
400 if (INET6_resolve(args_m1, (struct sockaddr_in6 *) &sa6) < 0) {
401 bb_error_msg_and_die("resolving %s", args_m1);
403 memcpy(&rt.rtmsg_gateway, sa6.sin6_addr.s6_addr,
404 sizeof(struct in6_addr));
405 rt.rtmsg_flags |= RTF_GATEWAY;
409 /* Device is special in that it can be the last arg specified
410 * and doesn't requre the dev/device keyword in that case. */
411 if (!devname && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) {
412 /* Don't use args_m1 here since args may have changed! */
417 /* Nothing matched. */
421 /* Create a socket to the INET6 kernel. */
422 skfd = xsocket(AF_INET6, SOCK_DGRAM, 0);
424 rt.rtmsg_ifindex = 0;
428 memset(&ifr, 0, sizeof(ifr));
429 strncpy_IFNAMSIZ(ifr.ifr_name, devname);
430 xioctl(skfd, SIOGIFINDEX, &ifr);
431 rt.rtmsg_ifindex = ifr.ifr_ifindex;
434 /* Tell the kernel to accept this route. */
435 if (action == RTACTION_ADD)
436 xioctl(skfd, SIOCADDRT, &rt);
438 xioctl(skfd, SIOCDELRT, &rt);
440 if (ENABLE_FEATURE_CLEAN_UP) close(skfd);
444 static const unsigned flagvals[] = { /* Must agree with flagchars[]. */
450 #if ENABLE_FEATURE_IPV6
457 #define IPV4_MASK (RTF_GATEWAY|RTF_HOST|RTF_REINSTATE|RTF_DYNAMIC|RTF_MODIFIED)
458 #define IPV6_MASK (RTF_GATEWAY|RTF_HOST|RTF_DEFAULT|RTF_ADDRCONF|RTF_CACHE)
460 /* Must agree with flagvals[]. */
461 static const char flagchars[] ALIGN1 =
463 #if ENABLE_FEATURE_IPV6
468 static void set_flags(char *flagstr, int flags)
474 for (i = 0; (*flagstr = flagchars[i]) != 0; i++) {
475 if (flags & flagvals[i]) {
481 /* also used in netstat */
482 void FAST_FUNC bb_displayroutes(int noresolve, int netstatfmt)
484 char devname[64], flags[16], *sdest, *sgw;
485 unsigned long d, g, m;
486 int flgs, ref, use, metric, mtu, win, ir;
487 struct sockaddr_in s_addr;
490 FILE *fp = xfopen_for_read("/proc/net/route");
492 printf("Kernel IP routing table\n"
493 "Destination Gateway Genmask Flags %s Iface\n",
494 netstatfmt ? " MSS Window irtt" : "Metric Ref Use");
496 if (fscanf(fp, "%*[^\n]\n") < 0) { /* Skip the first line. */
497 goto ERROR; /* Empty or missing line, or read error. */
501 r = fscanf(fp, "%63s%lx%lx%X%d%d%d%lx%d%d%d\n",
502 devname, &d, &g, &flgs, &ref, &use, &metric, &m,
505 if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
509 bb_error_msg_and_die("fscanf");
512 if (!(flgs & RTF_UP)) { /* Skip interfaces that are down. */
516 set_flags(flags, (flgs & IPV4_MASK));
518 if (flgs & RTF_REJECT) {
523 memset(&s_addr, 0, sizeof(struct sockaddr_in));
524 s_addr.sin_family = AF_INET;
525 s_addr.sin_addr.s_addr = d;
526 sdest = INET_rresolve(&s_addr, (noresolve | 0x8000), m); /* 'default' instead of '*' */
527 s_addr.sin_addr.s_addr = g;
528 sgw = INET_rresolve(&s_addr, (noresolve | 0x4000), m); /* Host instead of net */
530 /* "%15.15s" truncates hostnames, do we really want that? */
531 printf("%-15.15s %-15.15s %-16s%-6s", sdest, sgw, inet_ntoa(mask), flags);
535 printf("%5d %-5d %6d %s\n", mtu, win, ir, devname);
537 printf("%-6d %-2d %7d %s\n", metric, ref, use, devname);
542 #if ENABLE_FEATURE_IPV6
544 static void INET6_displayroutes(void)
546 char addr6[128], *naddr6;
547 /* In addr6x, we store both 40-byte ':'-delimited ipv6 addresses.
548 * We read the non-delimited strings into the tail of the buffer
549 * using fscanf and then modify the buffer by shifting forward
550 * while inserting ':'s and the nul terminator for the first string.
551 * Hence the strings are at addr6x and addr6x+40. This generates
552 * _much_ less code than the previous (upstream) approach. */
554 char iface[16], flags[16];
555 int iflags, metric, refcnt, use, prefix_len, slen;
556 struct sockaddr_in6 snaddr6;
558 FILE *fp = xfopen_for_read("/proc/net/ipv6_route");
560 printf("Kernel IPv6 routing table\n%-44s%-40s"
561 "Flags Metric Ref Use Iface\n",
562 "Destination", "Next Hop");
566 r = fscanf(fp, "%32s%x%*s%x%32s%x%x%x%x%s\n",
567 addr6x+14, &prefix_len, &slen, addr6x+40+7,
568 &metric, &use, &refcnt, &iflags, iface);
570 if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
574 bb_error_msg_and_die("fscanf");
577 /* Do the addr6x shift-and-insert changes to ':'-delimit addresses.
578 * For now, always do this to validate the proc route format, even
579 * if the interface is down. */
586 if (i == 40) { /* nul terminator for 1st address? */
587 addr6x[39] = 0; /* Fixup... need 0 instead of ':'. */
588 ++p; /* Skip and continue. */
597 } while (i < 40+28+7);
600 if (!(iflags & RTF_UP)) { /* Skip interfaces that are down. */
604 set_flags(flags, (iflags & IPV6_MASK));
608 inet_pton(AF_INET6, addr6x + r,
609 (struct sockaddr *) &snaddr6.sin6_addr);
610 snaddr6.sin6_family = AF_INET6;
611 naddr6 = INET6_rresolve((struct sockaddr_in6 *) &snaddr6,
612 0x0fff /* Apparently, upstream never resolves. */
615 if (!r) { /* 1st pass */
616 snprintf(addr6, sizeof(addr6), "%s/%d", naddr6, prefix_len);
619 } else { /* 2nd pass */
620 /* Print the info. */
621 printf("%-43s %-39s %-5s %-6d %-2d %7d %-8s\n",
622 addr6, naddr6, flags, metric, refcnt, use, iface);
632 #define ROUTE_OPT_A 0x01
633 #define ROUTE_OPT_n 0x02
634 #define ROUTE_OPT_e 0x04
635 #define ROUTE_OPT_INET6 0x08 /* Not an actual option. See below. */
637 /* 1st byte is offset to next entry offset. 2nd byte is return value. */
638 /* 2nd byte matches RTACTION_* code */
639 static const char tbl_verb[] ALIGN1 =
642 /* "\011\002delete\0" */
643 "\010\002delete" /* Since it's last, we can save a byte. */
646 int route_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
647 int route_main(int argc UNUSED_PARAM, char **argv)
654 /* First, remap '-net' and '-host' to avoid getopt problems. */
657 if (strcmp(*p, "-net") == 0 || strcmp(*p, "-host") == 0) {
662 opt = getopt32(argv, "A:ne", &family);
664 if ((opt & ROUTE_OPT_A) && strcmp(family, "inet") != 0) {
665 #if ENABLE_FEATURE_IPV6
666 if (strcmp(family, "inet6") == 0) {
667 opt |= ROUTE_OPT_INET6; /* Set flag for ipv6. */
675 /* No more args means display the routing table. */
677 int noresolve = (opt & ROUTE_OPT_n) ? 0x0fff : 0;
678 #if ENABLE_FEATURE_IPV6
679 if (opt & ROUTE_OPT_INET6)
680 INET6_displayroutes();
683 bb_displayroutes(noresolve, opt & ROUTE_OPT_e);
685 fflush_stdout_and_exit(EXIT_SUCCESS);
688 /* Check verb. At the moment, must be add, del, or delete. */
689 what = kw_lookup(tbl_verb, &argv);
690 if (!what || !*argv) { /* Unknown verb or no more args. */
694 #if ENABLE_FEATURE_IPV6
695 if (opt & ROUTE_OPT_INET6)
696 INET6_setroute(what, argv);
699 INET_setroute(what, argv);