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 tarball for details.
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 void INET_setroute(int action, char **args)
157 const char *netmask = NULL;
158 int skfd, isnet, xflag;
160 /* Grab the -net or -host options. Remember they were transformed. */
161 xflag = kw_lookup(tbl_hash_net_host, &args);
163 /* If we did grab -net or -host, make sure we still have an arg left. */
168 /* Clean out the RTREQ structure. */
169 memset(&rt, 0, sizeof(rt));
172 const char *target = *args++;
175 /* recognize x.x.x.x/mask format. */
176 prefix = strchr(target, '/');
180 prefix_len = xatoul_range(prefix+1, 0, 32);
181 mask_in_addr(rt) = htonl( ~ (0xffffffffUL >> prefix_len));
184 rt.rt_genmask.sa_family = AF_INET;
187 /* Default netmask. */
188 netmask = bb_str_default;
190 /* Prefer hostname lookup is -host flag (xflag==1) was given. */
191 isnet = INET_resolve(target, (struct sockaddr_in *) &rt.rt_dst,
192 (xflag & HOST_FLAG));
194 bb_error_msg_and_die("resolving %s", target);
197 /* do not destroy prefix for process args */
202 if (xflag) { /* Reinit isnet if -net or -host was specified. */
203 isnet = (xflag & NET_FLAG);
206 /* Fill in the other fields. */
207 rt.rt_flags = ((isnet) ? RTF_UP : (RTF_UP | RTF_HOST));
210 int k = kw_lookup(tbl_ipvx, &args);
211 const char *args_m1 = args[-1];
213 if (k & KW_IPVx_FLAG_ONLY) {
214 rt.rt_flags |= flags_ipvx[k & 3];
219 if (k == KW_IPVx_METRIC) {
220 rt.rt_metric = xatoul(args_m1) + 1;
225 if (k == KW_IPVx_NETMASK) {
226 struct sockaddr mask;
228 if (mask_in_addr(rt)) {
233 isnet = INET_resolve(netmask, (struct sockaddr_in *) &mask, 0);
235 bb_error_msg_and_die("resolving %s", netmask);
237 rt.rt_genmask = full_mask(mask);
241 if (k == KW_IPVx_GATEWAY) {
242 if (rt.rt_flags & RTF_GATEWAY) {
246 isnet = INET_resolve(args_m1,
247 (struct sockaddr_in *) &rt.rt_gateway, 1);
248 rt.rt_flags |= RTF_GATEWAY;
252 bb_error_msg_and_die("resolving %s", args_m1);
254 bb_error_msg_and_die("gateway %s is a NETWORK", args_m1);
259 if (k == KW_IPVx_MSS) { /* Check valid MSS bounds. */
260 rt.rt_flags |= RTF_MSS;
261 rt.rt_mss = xatoul_range(args_m1, 64, 32768);
265 if (k == KW_IPVx_WINDOW) { /* Check valid window bounds. */
266 rt.rt_flags |= RTF_WINDOW;
267 rt.rt_window = xatoul_range(args_m1, 128, INT_MAX);
272 if (k == KW_IPVx_IRTT) {
273 rt.rt_flags |= RTF_IRTT;
274 rt.rt_irtt = xatoul(args_m1);
275 rt.rt_irtt *= (sysconf(_SC_CLK_TCK) / 100); /* FIXME */
276 #if 0 /* FIXME: do we need to check anything of this? */
277 if (rt.rt_irtt < 1 || rt.rt_irtt > (120 * HZ)) {
278 bb_error_msg_and_die("bad irtt");
285 /* Device is special in that it can be the last arg specified
286 * and doesn't requre the dev/device keyword in that case. */
287 if (!rt.rt_dev && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) {
288 /* Don't use args_m1 here since args may have changed! */
289 rt.rt_dev = args[-1];
293 /* Nothing matched. */
298 if ((rt.rt_flags & RTF_REJECT) && !rt.rt_dev) {
299 rt.rt_dev = (char*)"lo";
303 /* sanity checks.. */
304 if (mask_in_addr(rt)) {
305 uint32_t mask = mask_in_addr(rt);
308 if ((rt.rt_flags & RTF_HOST) && mask != 0xffffffff) {
309 bb_error_msg_and_die("netmask %.8x and host route conflict",
310 (unsigned int) mask);
312 if (mask & (mask + 1)) {
313 bb_error_msg_and_die("bogus netmask %s", netmask);
315 mask = ((struct sockaddr_in *) &rt.rt_dst)->sin_addr.s_addr;
316 if (mask & ~(uint32_t)mask_in_addr(rt)) {
317 bb_error_msg_and_die("netmask and route address conflict");
321 /* Fill out netmask if still unset */
322 if ((action == RTACTION_ADD) && (rt.rt_flags & RTF_HOST)) {
323 mask_in_addr(rt) = 0xffffffff;
326 /* Create a socket to the INET kernel. */
327 skfd = xsocket(AF_INET, SOCK_DGRAM, 0);
329 if (action == RTACTION_ADD)
330 xioctl(skfd, SIOCADDRT, &rt);
332 xioctl(skfd, SIOCDELRT, &rt);
334 if (ENABLE_FEATURE_CLEAN_UP) close(skfd);
337 #if ENABLE_FEATURE_IPV6
339 static void INET6_setroute(int action, char **args)
341 struct sockaddr_in6 sa6;
343 int prefix_len, skfd;
346 /* We know args isn't NULL from the check in route_main. */
347 const char *target = *args++;
349 if (strcmp(target, bb_str_default) == 0) {
351 memset(&sa6, 0, sizeof(sa6));
354 cp = strchr(target, '/'); /* Yes... const to non is ok. */
357 prefix_len = xatoul_range(cp + 1, 0, 128);
361 if (INET6_resolve(target, (struct sockaddr_in6 *) &sa6) < 0) {
362 bb_error_msg_and_die("resolving %s", target);
366 /* Clean out the RTREQ structure. */
367 memset(&rt, 0, sizeof(rt));
369 memcpy(&rt.rtmsg_dst, sa6.sin6_addr.s6_addr, sizeof(struct in6_addr));
371 /* Fill in the other fields. */
372 rt.rtmsg_dst_len = prefix_len;
373 rt.rtmsg_flags = ((prefix_len == 128) ? (RTF_UP|RTF_HOST) : RTF_UP);
379 int k = kw_lookup(tbl_ipvx, &args);
380 const char *args_m1 = args[-1];
382 if ((k == KW_IPVx_MOD) || (k == KW_IPVx_DYN)) {
383 rt.rtmsg_flags |= flags_ipvx[k & 3];
387 if (k == KW_IPVx_METRIC) {
388 rt.rtmsg_metric = xatoul(args_m1);
392 if (k == KW_IPVx_GATEWAY) {
393 if (rt.rtmsg_flags & RTF_GATEWAY) {
397 if (INET6_resolve(args_m1, (struct sockaddr_in6 *) &sa6) < 0) {
398 bb_error_msg_and_die("resolving %s", args_m1);
400 memcpy(&rt.rtmsg_gateway, sa6.sin6_addr.s6_addr,
401 sizeof(struct in6_addr));
402 rt.rtmsg_flags |= RTF_GATEWAY;
406 /* Device is special in that it can be the last arg specified
407 * and doesn't requre the dev/device keyword in that case. */
408 if (!devname && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) {
409 /* Don't use args_m1 here since args may have changed! */
414 /* Nothing matched. */
418 /* Create a socket to the INET6 kernel. */
419 skfd = xsocket(AF_INET6, SOCK_DGRAM, 0);
421 rt.rtmsg_ifindex = 0;
425 memset(&ifr, 0, sizeof(ifr));
426 strncpy_IFNAMSIZ(ifr.ifr_name, devname);
427 xioctl(skfd, SIOGIFINDEX, &ifr);
428 rt.rtmsg_ifindex = ifr.ifr_ifindex;
431 /* Tell the kernel to accept this route. */
432 if (action == RTACTION_ADD)
433 xioctl(skfd, SIOCADDRT, &rt);
435 xioctl(skfd, SIOCDELRT, &rt);
437 if (ENABLE_FEATURE_CLEAN_UP) close(skfd);
441 static const unsigned flagvals[] = { /* Must agree with flagchars[]. */
447 #if ENABLE_FEATURE_IPV6
454 #define IPV4_MASK (RTF_GATEWAY|RTF_HOST|RTF_REINSTATE|RTF_DYNAMIC|RTF_MODIFIED)
455 #define IPV6_MASK (RTF_GATEWAY|RTF_HOST|RTF_DEFAULT|RTF_ADDRCONF|RTF_CACHE)
457 /* Must agree with flagvals[]. */
458 static const char flagchars[] ALIGN1 =
460 #if ENABLE_FEATURE_IPV6
465 static void set_flags(char *flagstr, int flags)
471 for (i = 0; (*flagstr = flagchars[i]) != 0; i++) {
472 if (flags & flagvals[i]) {
478 /* also used in netstat */
479 void FAST_FUNC bb_displayroutes(int noresolve, int netstatfmt)
481 char devname[64], flags[16], *sdest, *sgw;
482 unsigned long d, g, m;
483 int flgs, ref, use, metric, mtu, win, ir;
484 struct sockaddr_in s_addr;
487 FILE *fp = xfopen_for_read("/proc/net/route");
489 printf("Kernel IP routing table\n"
490 "Destination Gateway Genmask Flags %s Iface\n",
491 netstatfmt ? " MSS Window irtt" : "Metric Ref Use");
493 if (fscanf(fp, "%*[^\n]\n") < 0) { /* Skip the first line. */
494 goto ERROR; /* Empty or missing line, or read error. */
498 r = fscanf(fp, "%63s%lx%lx%X%d%d%d%lx%d%d%d\n",
499 devname, &d, &g, &flgs, &ref, &use, &metric, &m,
502 if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
506 bb_error_msg_and_die("fscanf");
509 if (!(flgs & RTF_UP)) { /* Skip interfaces that are down. */
513 set_flags(flags, (flgs & IPV4_MASK));
515 if (flgs & RTF_REJECT) {
520 memset(&s_addr, 0, sizeof(struct sockaddr_in));
521 s_addr.sin_family = AF_INET;
522 s_addr.sin_addr.s_addr = d;
523 sdest = INET_rresolve(&s_addr, (noresolve | 0x8000), m); /* 'default' instead of '*' */
524 s_addr.sin_addr.s_addr = g;
525 sgw = INET_rresolve(&s_addr, (noresolve | 0x4000), m); /* Host instead of net */
527 /* "%15.15s" truncates hostnames, do we really want that? */
528 printf("%-15.15s %-15.15s %-16s%-6s", sdest, sgw, inet_ntoa(mask), flags);
532 printf("%5d %-5d %6d %s\n", mtu, win, ir, devname);
534 printf("%-6d %-2d %7d %s\n", metric, ref, use, devname);
539 #if ENABLE_FEATURE_IPV6
541 static void INET6_displayroutes(void)
543 char addr6[128], *naddr6;
544 /* In addr6x, we store both 40-byte ':'-delimited ipv6 addresses.
545 * We read the non-delimited strings into the tail of the buffer
546 * using fscanf and then modify the buffer by shifting forward
547 * while inserting ':'s and the nul terminator for the first string.
548 * Hence the strings are at addr6x and addr6x+40. This generates
549 * _much_ less code than the previous (upstream) approach. */
551 char iface[16], flags[16];
552 int iflags, metric, refcnt, use, prefix_len, slen;
553 struct sockaddr_in6 snaddr6;
555 FILE *fp = xfopen_for_read("/proc/net/ipv6_route");
557 printf("Kernel IPv6 routing table\n%-44s%-40s"
558 "Flags Metric Ref Use Iface\n",
559 "Destination", "Next Hop");
563 r = fscanf(fp, "%32s%x%*s%x%32s%x%x%x%x%s\n",
564 addr6x+14, &prefix_len, &slen, addr6x+40+7,
565 &metric, &use, &refcnt, &iflags, iface);
567 if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
571 bb_error_msg_and_die("fscanf");
574 /* Do the addr6x shift-and-insert changes to ':'-delimit addresses.
575 * For now, always do this to validate the proc route format, even
576 * if the interface is down. */
583 if (i == 40) { /* nul terminator for 1st address? */
584 addr6x[39] = 0; /* Fixup... need 0 instead of ':'. */
585 ++p; /* Skip and continue. */
594 } while (i < 40+28+7);
597 if (!(iflags & RTF_UP)) { /* Skip interfaces that are down. */
601 set_flags(flags, (iflags & IPV6_MASK));
605 inet_pton(AF_INET6, addr6x + r,
606 (struct sockaddr *) &snaddr6.sin6_addr);
607 snaddr6.sin6_family = AF_INET6;
608 naddr6 = INET6_rresolve((struct sockaddr_in6 *) &snaddr6,
609 0x0fff /* Apparently, upstream never resolves. */
612 if (!r) { /* 1st pass */
613 snprintf(addr6, sizeof(addr6), "%s/%d", naddr6, prefix_len);
616 } else { /* 2nd pass */
617 /* Print the info. */
618 printf("%-43s %-39s %-5s %-6d %-2d %7d %-8s\n",
619 addr6, naddr6, flags, metric, refcnt, use, iface);
629 #define ROUTE_OPT_A 0x01
630 #define ROUTE_OPT_n 0x02
631 #define ROUTE_OPT_e 0x04
632 #define ROUTE_OPT_INET6 0x08 /* Not an actual option. See below. */
634 /* 1st byte is offset to next entry offset. 2nd byte is return value. */
635 /* 2nd byte matches RTACTION_* code */
636 static const char tbl_verb[] ALIGN1 =
639 /* "\011\002delete\0" */
640 "\010\002delete" /* Since it's last, we can save a byte. */
643 int route_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
644 int route_main(int argc UNUSED_PARAM, char **argv)
651 /* First, remap '-net' and '-host' to avoid getopt problems. */
654 if (strcmp(*p, "-net") == 0 || strcmp(*p, "-host") == 0) {
659 opt = getopt32(argv, "A:ne", &family);
661 if ((opt & ROUTE_OPT_A) && strcmp(family, "inet") != 0) {
662 #if ENABLE_FEATURE_IPV6
663 if (strcmp(family, "inet6") == 0) {
664 opt |= ROUTE_OPT_INET6; /* Set flag for ipv6. */
672 /* No more args means display the routing table. */
674 int noresolve = (opt & ROUTE_OPT_n) ? 0x0fff : 0;
675 #if ENABLE_FEATURE_IPV6
676 if (opt & ROUTE_OPT_INET6)
677 INET6_displayroutes();
680 bb_displayroutes(noresolve, opt & ROUTE_OPT_e);
682 fflush_stdout_and_exit(EXIT_SUCCESS);
685 /* Check verb. At the moment, must be add, del, or delete. */
686 what = kw_lookup(tbl_verb, &argv);
687 if (!what || !*argv) { /* Unknown verb or no more args. */
691 #if ENABLE_FEATURE_IPV6
692 if (opt & ROUTE_OPT_INET6)
693 INET6_setroute(what, argv);
696 INET_setroute(what, argv);