1 /*
2 * ipneigh.c "ip neigh".
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 *
11 */
12
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <unistd.h>
16 #include <syslog.h>
17 #include <fcntl.h>
18 #include <string.h>
19 #include <sys/time.h>
20 #include <sys/socket.h>
21 #include <netinet/in.h>
22 #include <netinet/ip.h>
23
24 #include "rt_names.h"
25 #include "utils.h"
26 #include "ip_common.h"
27
28 #define NUD_VALID (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
29 #define MAX_ROUNDS 10
30
31 static struct
32 {
33 int family;
34 int index;
35 int state;
36 int unused_only;
37 inet_prefix pfx;
38 int flushed;
39 char *flushb;
40 int flushp;
41 int flushe;
42 } filter;
43
44 static void usage(void) __attribute__((noreturn));
45
usage(void)46 static void usage(void)
47 {
48 fprintf(stderr, "Usage: ip neigh { add | del | change | replace } { ADDR [ lladdr LLADDR ]\n"
49 " [ nud { permanent | noarp | stale | reachable } ]\n"
50 " | proxy ADDR } [ dev DEV ]\n");
51 fprintf(stderr, " ip neigh {show|flush} [ to PREFIX ] [ dev DEV ] [ nud STATE ]\n");
52 exit(-1);
53 }
54
nud_state_a2n(unsigned * state,char * arg)55 int nud_state_a2n(unsigned *state, char *arg)
56 {
57 if (matches(arg, "permanent") == 0)
58 *state = NUD_PERMANENT;
59 else if (matches(arg, "reachable") == 0)
60 *state = NUD_REACHABLE;
61 else if (strcmp(arg, "noarp") == 0)
62 *state = NUD_NOARP;
63 else if (strcmp(arg, "none") == 0)
64 *state = NUD_NONE;
65 else if (strcmp(arg, "stale") == 0)
66 *state = NUD_STALE;
67 else if (strcmp(arg, "incomplete") == 0)
68 *state = NUD_INCOMPLETE;
69 else if (strcmp(arg, "delay") == 0)
70 *state = NUD_DELAY;
71 else if (strcmp(arg, "probe") == 0)
72 *state = NUD_PROBE;
73 else if (matches(arg, "failed") == 0)
74 *state = NUD_FAILED;
75 else {
76 if (get_unsigned(state, arg, 0))
77 return -1;
78 if (*state>=0x100 || (*state&((*state)-1)))
79 return -1;
80 }
81 return 0;
82 }
83
flush_update(void)84 static int flush_update(void)
85 {
86 if (rtnl_send_check(&rth, filter.flushb, filter.flushp) < 0) {
87 perror("Failed to send flush request");
88 return -1;
89 }
90 filter.flushp = 0;
91 return 0;
92 }
93
94
ipneigh_modify(int cmd,int flags,int argc,char ** argv)95 static int ipneigh_modify(int cmd, int flags, int argc, char **argv)
96 {
97 struct {
98 struct nlmsghdr n;
99 struct ndmsg ndm;
100 char buf[256];
101 } req;
102 char *d = NULL;
103 int dst_ok = 0;
104 int lladdr_ok = 0;
105 char * lla = NULL;
106 inet_prefix dst;
107
108 memset(&req, 0, sizeof(req));
109
110 req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg));
111 req.n.nlmsg_flags = NLM_F_REQUEST|flags;
112 req.n.nlmsg_type = cmd;
113 req.ndm.ndm_family = preferred_family;
114 req.ndm.ndm_state = NUD_PERMANENT;
115
116 while (argc > 0) {
117 if (matches(*argv, "lladdr") == 0) {
118 NEXT_ARG();
119 if (lladdr_ok)
120 duparg("lladdr", *argv);
121 lla = *argv;
122 lladdr_ok = 1;
123 } else if (strcmp(*argv, "nud") == 0) {
124 unsigned state;
125 NEXT_ARG();
126 if (nud_state_a2n(&state, *argv))
127 invarg("nud state is bad", *argv);
128 req.ndm.ndm_state = state;
129 } else if (matches(*argv, "proxy") == 0) {
130 NEXT_ARG();
131 if (matches(*argv, "help") == 0)
132 usage();
133 if (dst_ok)
134 duparg("address", *argv);
135 get_addr(&dst, *argv, preferred_family);
136 dst_ok = 1;
137 req.ndm.ndm_flags |= NTF_PROXY;
138 } else if (strcmp(*argv, "dev") == 0) {
139 NEXT_ARG();
140 d = *argv;
141 } else {
142 if (strcmp(*argv, "to") == 0) {
143 NEXT_ARG();
144 }
145 if (matches(*argv, "help") == 0) {
146 NEXT_ARG();
147 }
148 if (dst_ok)
149 duparg2("to", *argv);
150 get_addr(&dst, *argv, preferred_family);
151 dst_ok = 1;
152 }
153 argc--; argv++;
154 }
155 if (d == NULL || !dst_ok || dst.family == AF_UNSPEC) {
156 fprintf(stderr, "Device and destination are required arguments.\n");
157 exit(-1);
158 }
159 req.ndm.ndm_family = dst.family;
160 addattr_l(&req.n, sizeof(req), NDA_DST, &dst.data, dst.bytelen);
161
162 if (lla && strcmp(lla, "null")) {
163 char llabuf[20];
164 int l;
165
166 l = ll_addr_a2n(llabuf, sizeof(llabuf), lla);
167 addattr_l(&req.n, sizeof(req), NDA_LLADDR, llabuf, l);
168 }
169
170 ll_init_map(&rth);
171
172 if ((req.ndm.ndm_ifindex = ll_name_to_index(d)) == 0) {
173 fprintf(stderr, "Cannot find device \"%s\"\n", d);
174 return -1;
175 }
176
177 if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0)
178 exit(2);
179
180 return 0;
181 }
182
183
print_neigh(const struct sockaddr_nl * who,struct nlmsghdr * n,void * arg)184 int print_neigh(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
185 {
186 FILE *fp = (FILE*)arg;
187 struct ndmsg *r = NLMSG_DATA(n);
188 int len = n->nlmsg_len;
189 struct rtattr * tb[NDA_MAX+1];
190 char abuf[256];
191
192 if (n->nlmsg_type != RTM_NEWNEIGH && n->nlmsg_type != RTM_DELNEIGH) {
193 fprintf(stderr, "Not RTM_NEWNEIGH: %08x %08x %08x\n",
194 n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
195
196 return 0;
197 }
198 len -= NLMSG_LENGTH(sizeof(*r));
199 if (len < 0) {
200 fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
201 return -1;
202 }
203
204 if (filter.flushb && n->nlmsg_type != RTM_NEWNEIGH)
205 return 0;
206
207 if (filter.family && filter.family != r->ndm_family)
208 return 0;
209 if (filter.index && filter.index != r->ndm_ifindex)
210 return 0;
211 if (!(filter.state&r->ndm_state) &&
212 (r->ndm_state || !(filter.state&0x100)) &&
213 (r->ndm_family != AF_DECnet))
214 return 0;
215
216 parse_rtattr(tb, NDA_MAX, NDA_RTA(r), n->nlmsg_len - NLMSG_LENGTH(sizeof(*r)));
217
218 if (tb[NDA_DST]) {
219 if (filter.pfx.family) {
220 inet_prefix dst;
221 memset(&dst, 0, sizeof(dst));
222 dst.family = r->ndm_family;
223 memcpy(&dst.data, RTA_DATA(tb[NDA_DST]), RTA_PAYLOAD(tb[NDA_DST]));
224 if (inet_addr_match(&dst, &filter.pfx, filter.pfx.bitlen))
225 return 0;
226 }
227 }
228 if (filter.unused_only && tb[NDA_CACHEINFO]) {
229 struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
230 if (ci->ndm_refcnt)
231 return 0;
232 }
233
234 if (filter.flushb) {
235 struct nlmsghdr *fn;
236 if (NLMSG_ALIGN(filter.flushp) + n->nlmsg_len > filter.flushe) {
237 if (flush_update())
238 return -1;
239 }
240 fn = (struct nlmsghdr*)(filter.flushb + NLMSG_ALIGN(filter.flushp));
241 memcpy(fn, n, n->nlmsg_len);
242 fn->nlmsg_type = RTM_DELNEIGH;
243 fn->nlmsg_flags = NLM_F_REQUEST;
244 fn->nlmsg_seq = ++rth.seq;
245 filter.flushp = (((char*)fn) + n->nlmsg_len) - filter.flushb;
246 filter.flushed++;
247 if (show_stats < 2)
248 return 0;
249 }
250
251 if (tb[NDA_DST]) {
252 fprintf(fp, "%s ",
253 format_host(r->ndm_family,
254 RTA_PAYLOAD(tb[NDA_DST]),
255 RTA_DATA(tb[NDA_DST]),
256 abuf, sizeof(abuf)));
257 }
258 if (!filter.index && r->ndm_ifindex)
259 fprintf(fp, "dev %s ", ll_index_to_name(r->ndm_ifindex));
260 if (tb[NDA_LLADDR]) {
261 SPRINT_BUF(b1);
262 fprintf(fp, "lladdr %s", ll_addr_n2a(RTA_DATA(tb[NDA_LLADDR]),
263 RTA_PAYLOAD(tb[NDA_LLADDR]),
264 ll_index_to_type(r->ndm_ifindex),
265 b1, sizeof(b1)));
266 }
267 if (r->ndm_flags & NTF_ROUTER) {
268 fprintf(fp, " router");
269 }
270 if (tb[NDA_CACHEINFO] && show_stats) {
271 struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
272 int hz = get_user_hz();
273
274 if (ci->ndm_refcnt)
275 printf(" ref %d", ci->ndm_refcnt);
276 fprintf(fp, " used %d/%d/%d", ci->ndm_used/hz,
277 ci->ndm_confirmed/hz, ci->ndm_updated/hz);
278 }
279
280 #ifdef NDA_PROBES
281 if (tb[NDA_PROBES] && show_stats) {
282 __u32 p = *(__u32 *) RTA_DATA(tb[NDA_PROBES]);
283 fprintf(fp, " probes %u", p);
284 }
285 #endif
286
287 if (r->ndm_state) {
288 int nud = r->ndm_state;
289 fprintf(fp, " ");
290
291 #define PRINT_FLAG(f) if (nud & NUD_##f) { \
292 nud &= ~NUD_##f; fprintf(fp, #f "%s", nud ? "," : ""); }
293 PRINT_FLAG(INCOMPLETE);
294 PRINT_FLAG(REACHABLE);
295 PRINT_FLAG(STALE);
296 PRINT_FLAG(DELAY);
297 PRINT_FLAG(PROBE);
298 PRINT_FLAG(FAILED);
299 PRINT_FLAG(NOARP);
300 PRINT_FLAG(PERMANENT);
301 #undef PRINT_FLAG
302 }
303 fprintf(fp, "\n");
304
305 fflush(fp);
306 return 0;
307 }
308
ipneigh_reset_filter()309 void ipneigh_reset_filter()
310 {
311 memset(&filter, 0, sizeof(filter));
312 filter.state = ~0;
313 }
314
do_show_or_flush(int argc,char ** argv,int flush)315 int do_show_or_flush(int argc, char **argv, int flush)
316 {
317 char *filter_dev = NULL;
318 int state_given = 0;
319
320 ipneigh_reset_filter();
321
322 if (!filter.family)
323 filter.family = preferred_family;
324
325 if (flush) {
326 if (argc <= 0) {
327 fprintf(stderr, "Flush requires arguments.\n");
328 return -1;
329 }
330 filter.state = ~(NUD_PERMANENT|NUD_NOARP);
331 } else
332 filter.state = 0xFF & ~NUD_NOARP;
333
334 while (argc > 0) {
335 if (strcmp(*argv, "dev") == 0) {
336 NEXT_ARG();
337 if (filter_dev)
338 duparg("dev", *argv);
339 filter_dev = *argv;
340 } else if (strcmp(*argv, "unused") == 0) {
341 filter.unused_only = 1;
342 } else if (strcmp(*argv, "nud") == 0) {
343 unsigned state;
344 NEXT_ARG();
345 if (!state_given) {
346 state_given = 1;
347 filter.state = 0;
348 }
349 if (nud_state_a2n(&state, *argv)) {
350 if (strcmp(*argv, "all") != 0)
351 invarg("nud state is bad", *argv);
352 state = ~0;
353 if (flush)
354 state &= ~NUD_NOARP;
355 }
356 if (state == 0)
357 state = 0x100;
358 filter.state |= state;
359 } else {
360 if (strcmp(*argv, "to") == 0) {
361 NEXT_ARG();
362 }
363 if (matches(*argv, "help") == 0)
364 usage();
365 get_prefix(&filter.pfx, *argv, filter.family);
366 if (filter.family == AF_UNSPEC)
367 filter.family = filter.pfx.family;
368 }
369 argc--; argv++;
370 }
371
372 ll_init_map(&rth);
373
374 if (filter_dev) {
375 if ((filter.index = ll_name_to_index(filter_dev)) == 0) {
376 fprintf(stderr, "Cannot find device \"%s\"\n", filter_dev);
377 return -1;
378 }
379 }
380
381 if (flush) {
382 int round = 0;
383 char flushb[4096-512];
384
385 filter.flushb = flushb;
386 filter.flushp = 0;
387 filter.flushe = sizeof(flushb);
388 filter.state &= ~NUD_FAILED;
389
390 while (round < MAX_ROUNDS) {
391 if (rtnl_wilddump_request(&rth, filter.family, RTM_GETNEIGH) < 0) {
392 perror("Cannot send dump request");
393 exit(1);
394 }
395 filter.flushed = 0;
396 if (rtnl_dump_filter(&rth, print_neigh, stdout, NULL, NULL) < 0) {
397 fprintf(stderr, "Flush terminated\n");
398 exit(1);
399 }
400 if (filter.flushed == 0) {
401 if (show_stats) {
402 if (round == 0)
403 printf("Nothing to flush.\n");
404 else
405 printf("*** Flush is complete after %d round%s ***\n", round, round>1?"s":"");
406 }
407 fflush(stdout);
408 return 0;
409 }
410 round++;
411 if (flush_update() < 0)
412 exit(1);
413 if (show_stats) {
414 printf("\n*** Round %d, deleting %d entries ***\n", round, filter.flushed);
415 fflush(stdout);
416 }
417 }
418 printf("*** Flush not complete bailing out after %d rounds\n",
419 MAX_ROUNDS);
420 return 1;
421 }
422
423 if (rtnl_wilddump_request(&rth, filter.family, RTM_GETNEIGH) < 0) {
424 perror("Cannot send dump request");
425 exit(1);
426 }
427
428 if (rtnl_dump_filter(&rth, print_neigh, stdout, NULL, NULL) < 0) {
429 fprintf(stderr, "Dump terminated\n");
430 exit(1);
431 }
432
433 return 0;
434 }
435
do_ipneigh(int argc,char ** argv)436 int do_ipneigh(int argc, char **argv)
437 {
438 if (argc > 0) {
439 if (matches(*argv, "add") == 0)
440 return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_EXCL, argc-1, argv+1);
441 if (matches(*argv, "change") == 0 ||
442 strcmp(*argv, "chg") == 0)
443 return ipneigh_modify(RTM_NEWNEIGH, NLM_F_REPLACE, argc-1, argv+1);
444 if (matches(*argv, "replace") == 0)
445 return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_REPLACE, argc-1, argv+1);
446 if (matches(*argv, "delete") == 0)
447 return ipneigh_modify(RTM_DELNEIGH, 0, argc-1, argv+1);
448 if (matches(*argv, "get") == 0) {
449 fprintf(stderr, "Sorry, \"neigh get\" is not implemented :-(\n");
450 return -1;
451 }
452 if (matches(*argv, "show") == 0 ||
453 matches(*argv, "lst") == 0 ||
454 matches(*argv, "list") == 0)
455 return do_show_or_flush(argc-1, argv+1, 0);
456 if (matches(*argv, "flush") == 0)
457 return do_show_or_flush(argc-1, argv+1, 1);
458 if (matches(*argv, "help") == 0)
459 usage();
460 } else
461 return do_show_or_flush(0, NULL, 0);
462
463 fprintf(stderr, "Command \"%s\" is unknown, try \"ip neigh help\".\n", *argv);
464 exit(-1);
465 }
466