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.
29 #include <net/route.h>
33 #include "inet_common.h"
37 /* Keep this in sync with /usr/src/linux/include/linux/route.h */
38 #define RTF_UP 0x0001 /* route usable */
39 #define RTF_GATEWAY 0x0002 /* destination is a gateway */
40 #define RTF_HOST 0x0004 /* host entry (net otherwise) */
41 #define RTF_REINSTATE 0x0008 /* reinstate route after tmout */
42 #define RTF_DYNAMIC 0x0010 /* created dyn. (by redirect) */
43 #define RTF_MODIFIED 0x0020 /* modified dyn. (by redirect) */
44 #define RTF_MTU 0x0040 /* specific MTU for this route */
46 #define RTF_MSS RTF_MTU /* Compatibility :-( */
48 #define RTF_WINDOW 0x0080 /* per route window clamping */
49 #define RTF_IRTT 0x0100 /* Initial round trip time */
50 #define RTF_REJECT 0x0200 /* Reject route */
53 #if defined(SIOCADDRTOLD) || defined(RTF_IRTT) /* route */
54 #define HAVE_NEW_ADDRT 1
58 #define mask_in_addr(x) (((struct sockaddr_in *)&((x).rt_genmask))->sin_addr.s_addr)
59 #define full_mask(x) (x)
61 #define mask_in_addr(x) ((x).rt_genmask)
62 #define full_mask(x) (((struct sockaddr_in *)&(x))->sin_addr.s_addr)
65 /* The RTACTION entries must agree with tbl_verb[] below! */
66 #define RTACTION_ADD 1
67 #define RTACTION_DEL 2
69 /* For the various tbl_*[] arrays, the 1st byte is the offset to
70 * the next entry and the 2nd byte is return value. */
75 /* We remap '-' to '#' to avoid problems with getopt. */
76 static const char tbl_hash_net_host[] ALIGN1 =
78 /* "\010\002#host\0" */
79 "\007\002#host" /* Since last, we can save a byte. */
82 #define KW_TAKES_ARG 020
83 #define KW_SETS_FLAG 040
85 #define KW_IPVx_METRIC 020
86 #define KW_IPVx_NETMASK 021
87 #define KW_IPVx_GATEWAY 022
88 #define KW_IPVx_MSS 023
89 #define KW_IPVx_WINDOW 024
90 #define KW_IPVx_IRTT 025
91 #define KW_IPVx_DEVICE 026
93 #define KW_IPVx_FLAG_ONLY 040
94 #define KW_IPVx_REJECT 040
95 #define KW_IPVx_MOD 041
96 #define KW_IPVx_DYN 042
97 #define KW_IPVx_REINSTATE 043
99 static const char tbl_ipvx[] ALIGN1 =
100 /* 020 is the "takes an arg" bit */
114 /* 040 is the "sets a flag" bit - MUST match flags_ipvx[] values below. */
120 /* "\014\043reinstate\0" */
121 "\013\043reinstate" /* Since last, we can save a byte. */
124 static const int flags_ipvx[] = { /* MUST match tbl_ipvx[] values above. */
133 static int kw_lookup(const char *kwtbl, char ***pargs)
137 if (strcmp(kwtbl+2, **pargs) == 0) { /* Found a match. */
139 if (kwtbl[1] & KW_TAKES_ARG) {
140 if (!**pargs) { /* No more args! */
143 *pargs += 1; /* Calling routine will use args[-1]. */
153 /* Add or delete a route, depending on action. */
155 static void INET_setroute(int action, char **args)
158 const char *netmask = NULL;
159 int skfd, isnet, xflag;
161 /* Grab the -net or -host options. Remember they were transformed. */
162 xflag = kw_lookup(tbl_hash_net_host, &args);
164 /* If we did grab -net or -host, make sure we still have an arg left. */
169 /* Clean out the RTREQ structure. */
170 memset(&rt, 0, sizeof(rt));
173 const char *target = *args++;
176 /* recognize x.x.x.x/mask format. */
177 prefix = strchr(target, '/');
181 prefix_len = xatoul_range(prefix+1, 0, 32);
182 mask_in_addr(rt) = htonl( ~ (0xffffffffUL >> prefix_len));
185 rt.rt_genmask.sa_family = AF_INET;
188 /* Default netmask. */
189 netmask = bb_str_default;
191 /* Prefer hostname lookup is -host flag (xflag==1) was given. */
192 isnet = INET_resolve(target, (struct sockaddr_in *) &rt.rt_dst,
193 (xflag & HOST_FLAG));
195 bb_error_msg_and_die("resolving %s", target);
198 /* do not destroy prefix for process args */
203 if (xflag) { /* Reinit isnet if -net or -host was specified. */
204 isnet = (xflag & NET_FLAG);
207 /* Fill in the other fields. */
208 rt.rt_flags = ((isnet) ? RTF_UP : (RTF_UP | RTF_HOST));
211 int k = kw_lookup(tbl_ipvx, &args);
212 const char *args_m1 = args[-1];
214 if (k & KW_IPVx_FLAG_ONLY) {
215 rt.rt_flags |= flags_ipvx[k & 3];
220 if (k == KW_IPVx_METRIC) {
221 rt.rt_metric = xatoul(args_m1) + 1;
226 if (k == KW_IPVx_NETMASK) {
227 struct sockaddr mask;
229 if (mask_in_addr(rt)) {
234 isnet = INET_resolve(netmask, (struct sockaddr_in *) &mask, 0);
236 bb_error_msg_and_die("resolving %s", netmask);
238 rt.rt_genmask = full_mask(mask);
242 if (k == KW_IPVx_GATEWAY) {
243 if (rt.rt_flags & RTF_GATEWAY) {
247 isnet = INET_resolve(args_m1,
248 (struct sockaddr_in *) &rt.rt_gateway, 1);
249 rt.rt_flags |= RTF_GATEWAY;
253 bb_error_msg_and_die("resolving %s", args_m1);
255 bb_error_msg_and_die("gateway %s is a NETWORK", args_m1);
260 if (k == KW_IPVx_MSS) { /* Check valid MSS bounds. */
261 rt.rt_flags |= RTF_MSS;
262 rt.rt_mss = xatoul_range(args_m1, 64, 32768);
266 if (k == KW_IPVx_WINDOW) { /* Check valid window bounds. */
267 rt.rt_flags |= RTF_WINDOW;
268 rt.rt_window = xatoul_range(args_m1, 128, INT_MAX);
273 if (k == KW_IPVx_IRTT) {
274 rt.rt_flags |= RTF_IRTT;
275 rt.rt_irtt = xatoul(args_m1);
276 rt.rt_irtt *= (sysconf(_SC_CLK_TCK) / 100); /* FIXME */
277 #if 0 /* FIXME: do we need to check anything of this? */
278 if (rt.rt_irtt < 1 || rt.rt_irtt > (120 * HZ)) {
279 bb_error_msg_and_die("bad irtt");
286 /* Device is special in that it can be the last arg specified
287 * and doesn't requre the dev/device keyword in that case. */
288 if (!rt.rt_dev && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) {
289 /* Don't use args_m1 here since args may have changed! */
290 rt.rt_dev = args[-1];
294 /* Nothing matched. */
299 if ((rt.rt_flags & RTF_REJECT) && !rt.rt_dev) {
300 rt.rt_dev = (char*)"lo";
304 /* sanity checks.. */
305 if (mask_in_addr(rt)) {
306 unsigned long mask = mask_in_addr(rt);
309 if ((rt.rt_flags & RTF_HOST) && mask != 0xffffffff) {
310 bb_error_msg_and_die("netmask %.8x and host route conflict",
311 (unsigned int) mask);
313 if (mask & (mask + 1)) {
314 bb_error_msg_and_die("bogus netmask %s", netmask);
316 mask = ((struct sockaddr_in *) &rt.rt_dst)->sin_addr.s_addr;
317 if (mask & ~mask_in_addr(rt)) {
318 bb_error_msg_and_die("netmask and route address conflict");
322 /* Fill out netmask if still unset */
323 if ((action == RTACTION_ADD) && (rt.rt_flags & RTF_HOST)) {
324 mask_in_addr(rt) = 0xffffffff;
327 /* Create a socket to the INET kernel. */
328 skfd = xsocket(AF_INET, SOCK_DGRAM, 0);
330 if (action == RTACTION_ADD)
331 xioctl(skfd, SIOCADDRT, &rt);
333 xioctl(skfd, SIOCDELRT, &rt);
335 if (ENABLE_FEATURE_CLEAN_UP) close(skfd);
338 #if ENABLE_FEATURE_IPV6
340 static void INET6_setroute(int action, char **args)
342 struct sockaddr_in6 sa6;
344 int prefix_len, skfd;
347 /* We know args isn't NULL from the check in route_main. */
348 const char *target = *args++;
350 if (strcmp(target, bb_str_default) == 0) {
352 memset(&sa6, 0, sizeof(sa6));
355 cp = strchr(target, '/'); /* Yes... const to non is ok. */
358 prefix_len = xatoul_range(cp + 1, 0, 128);
362 if (INET6_resolve(target, (struct sockaddr_in6 *) &sa6) < 0) {
363 bb_error_msg_and_die("resolving %s", target);
367 /* Clean out the RTREQ structure. */
368 memset(&rt, 0, sizeof(rt));
370 memcpy(&rt.rtmsg_dst, sa6.sin6_addr.s6_addr, sizeof(struct in6_addr));
372 /* Fill in the other fields. */
373 rt.rtmsg_dst_len = prefix_len;
374 rt.rtmsg_flags = ((prefix_len == 128) ? (RTF_UP|RTF_HOST) : RTF_UP);
380 int k = kw_lookup(tbl_ipvx, &args);
381 const char *args_m1 = args[-1];
383 if ((k == KW_IPVx_MOD) || (k == KW_IPVx_DYN)) {
384 rt.rtmsg_flags |= flags_ipvx[k & 3];
388 if (k == KW_IPVx_METRIC) {
389 rt.rtmsg_metric = xatoul(args_m1);
393 if (k == KW_IPVx_GATEWAY) {
394 if (rt.rtmsg_flags & RTF_GATEWAY) {
398 if (INET6_resolve(args_m1, (struct sockaddr_in6 *) &sa6) < 0) {
399 bb_error_msg_and_die("resolving %s", args_m1);
401 memcpy(&rt.rtmsg_gateway, sa6.sin6_addr.s6_addr,
402 sizeof(struct in6_addr));
403 rt.rtmsg_flags |= RTF_GATEWAY;
407 /* Device is special in that it can be the last arg specified
408 * and doesn't requre the dev/device keyword in that case. */
409 if (!devname && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) {
410 /* Don't use args_m1 here since args may have changed! */
415 /* Nothing matched. */
419 /* Create a socket to the INET6 kernel. */
420 skfd = xsocket(AF_INET6, SOCK_DGRAM, 0);
422 rt.rtmsg_ifindex = 0;
426 memset(&ifr, 0, sizeof(ifr));
427 strncpy(ifr.ifr_name, devname, sizeof(ifr.ifr_name));
428 xioctl(skfd, SIOGIFINDEX, &ifr);
429 rt.rtmsg_ifindex = ifr.ifr_ifindex;
432 /* Tell the kernel to accept this route. */
433 if (action == RTACTION_ADD)
434 xioctl(skfd, SIOCADDRT, &rt);
436 xioctl(skfd, SIOCDELRT, &rt);
438 if (ENABLE_FEATURE_CLEAN_UP) close(skfd);
442 static const unsigned flagvals[] = { /* Must agree with flagchars[]. */
448 #if ENABLE_FEATURE_IPV6
455 #define IPV4_MASK (RTF_GATEWAY|RTF_HOST|RTF_REINSTATE|RTF_DYNAMIC|RTF_MODIFIED)
456 #define IPV6_MASK (RTF_GATEWAY|RTF_HOST|RTF_DEFAULT|RTF_ADDRCONF|RTF_CACHE)
458 /* Must agree with flagvals[]. */
459 static const char flagchars[] ALIGN1 =
461 #if ENABLE_FEATURE_IPV6
466 static void set_flags(char *flagstr, int flags)
472 for (i = 0; (*flagstr = flagchars[i]) != 0; i++) {
473 if (flags & flagvals[i]) {
479 /* also used in netstat */
480 void bb_displayroutes(int noresolve, int netstatfmt)
482 char devname[64], flags[16], *sdest, *sgw;
483 unsigned long d, g, m;
484 int flgs, ref, use, metric, mtu, win, ir;
485 struct sockaddr_in s_addr;
488 FILE *fp = xfopen("/proc/net/route", "r");
490 printf("Kernel IP routing table\n"
491 "Destination Gateway Genmask Flags %s Iface\n",
492 netstatfmt ? " MSS Window irtt" : "Metric Ref Use");
494 if (fscanf(fp, "%*[^\n]\n") < 0) { /* Skip the first line. */
495 goto ERROR; /* Empty or missing line, or read error. */
499 r = fscanf(fp, "%63s%lx%lx%X%d%d%d%lx%d%d%d\n",
500 devname, &d, &g, &flgs, &ref, &use, &metric, &m,
503 if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
507 bb_error_msg_and_die("fscanf");
510 if (!(flgs & RTF_UP)) { /* Skip interfaces that are down. */
514 set_flags(flags, (flgs & IPV4_MASK));
516 if (flgs & RTF_REJECT) {
521 memset(&s_addr, 0, sizeof(struct sockaddr_in));
522 s_addr.sin_family = AF_INET;
523 s_addr.sin_addr.s_addr = d;
524 sdest = INET_rresolve(&s_addr, (noresolve | 0x8000), m); /* 'default' instead of '*' */
525 s_addr.sin_addr.s_addr = g;
526 sgw = INET_rresolve(&s_addr, (noresolve | 0x4000), m); /* Host instead of net */
528 /* "%15.15s" truncates hostnames, do we really want that? */
529 printf("%-15.15s %-15.15s %-16s%-6s", sdest, sgw, inet_ntoa(mask), flags);
533 printf("%5d %-5d %6d %s\n", mtu, win, ir, devname);
535 printf("%-6d %-2d %7d %s\n", metric, ref, use, devname);
540 #if ENABLE_FEATURE_IPV6
542 static void INET6_displayroutes(int noresolve)
544 char addr6[128], *naddr6;
545 /* In addr6x, we store both 40-byte ':'-delimited ipv6 addresses.
546 * We read the non-delimited strings into the tail of the buffer
547 * using fscanf and then modify the buffer by shifting forward
548 * while inserting ':'s and the nul terminator for the first string.
549 * Hence the strings are at addr6x and addr6x+40. This generates
550 * _much_ less code than the previous (upstream) approach. */
552 char iface[16], flags[16];
553 int iflags, metric, refcnt, use, prefix_len, slen;
554 struct sockaddr_in6 snaddr6;
556 FILE *fp = xfopen("/proc/net/ipv6_route", "r");
558 printf("Kernel IPv6 routing table\n%-44s%-40s"
559 "Flags Metric Ref Use Iface\n",
560 "Destination", "Next Hop");
564 r = fscanf(fp, "%32s%x%*s%x%32s%x%x%x%x%s\n",
565 addr6x+14, &prefix_len, &slen, addr6x+40+7,
566 &metric, &use, &refcnt, &iflags, iface);
568 if ((r < 0) && feof(fp)) { /* EOF with no (nonspace) chars read. */
572 bb_error_msg_and_die("fscanf");
575 /* Do the addr6x shift-and-insert changes to ':'-delimit addresses.
576 * For now, always do this to validate the proc route format, even
577 * if the interface is down. */
584 if (i == 40) { /* nul terminator for 1st address? */
585 addr6x[39] = 0; /* Fixup... need 0 instead of ':'. */
586 ++p; /* Skip and continue. */
595 } while (i < 40+28+7);
598 if (!(iflags & RTF_UP)) { /* Skip interfaces that are down. */
602 set_flags(flags, (iflags & IPV6_MASK));
606 inet_pton(AF_INET6, addr6x + r,
607 (struct sockaddr *) &snaddr6.sin6_addr);
608 snaddr6.sin6_family = AF_INET6;
609 naddr6 = INET6_rresolve((struct sockaddr_in6 *) &snaddr6,
610 0x0fff /* Apparently, upstream never resolves. */
613 if (!r) { /* 1st pass */
614 snprintf(addr6, sizeof(addr6), "%s/%d", naddr6, prefix_len);
617 } else { /* 2nd pass */
618 /* Print the info. */
619 printf("%-43s %-39s %-5s %-6d %-2d %7d %-8s\n",
620 addr6, naddr6, flags, metric, refcnt, use, iface);
630 #define ROUTE_OPT_A 0x01
631 #define ROUTE_OPT_n 0x02
632 #define ROUTE_OPT_e 0x04
633 #define ROUTE_OPT_INET6 0x08 /* Not an actual option. See below. */
635 /* 1st byte is offset to next entry offset. 2nd byte is return value. */
636 /* 2nd byte matches RTACTION_* code */
637 static const char tbl_verb[] ALIGN1 =
640 /* "\011\002delete\0" */
641 "\010\002delete" /* Since it's last, we can save a byte. */
644 int route_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
645 int route_main(int argc, char **argv)
652 /* First, remap '-net' and '-host' to avoid getopt problems. */
655 if (strcmp(*p, "-net") == 0 || strcmp(*p, "-host") == 0) {
660 opt = getopt32(argv, "A:ne", &family);
662 if ((opt & ROUTE_OPT_A) && strcmp(family, "inet") != 0) {
663 #if ENABLE_FEATURE_IPV6
664 if (strcmp(family, "inet6") == 0) {
665 opt |= ROUTE_OPT_INET6; /* Set flag for ipv6. */
673 /* No more args means display the routing table. */
675 int noresolve = (opt & ROUTE_OPT_n) ? 0x0fff : 0;
676 #if ENABLE_FEATURE_IPV6
677 if (opt & ROUTE_OPT_INET6)
678 INET6_displayroutes(noresolve);
681 bb_displayroutes(noresolve, opt & ROUTE_OPT_e);
683 fflush_stdout_and_exit(EXIT_SUCCESS);
686 /* Check verb. At the moment, must be add, del, or delete. */
687 what = kw_lookup(tbl_verb, &argv);
688 if (!what || !*argv) { /* Unknown verb or no more args. */
692 #if ENABLE_FEATURE_IPV6
693 if (opt & ROUTE_OPT_INET6)
694 INET6_setroute(what, argv);
697 INET_setroute(what, argv);