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 * Changes:
13 *
14 * Rani Assaf <rani@magic.metawire.com> 980929:	resolve addresses
15 */
16
17#include <stdio.h>
18#include <stdlib.h>
19#include <unistd.h>
20#include <syslog.h>
21#include <fcntl.h>
22#include <string.h>
23#include <sys/time.h>
24#include <net/if.h>
25#include <sys/socket.h>
26#include <netinet/in.h>
27#include <netinet/ip.h>
28
29#include "rt_names.h"
30#include "utils.h"
31#include "ip_common.h"
32
33#define NUD_VALID	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
34#define MAX_ROUNDS	10
35
36static struct
37{
38	int family;
39        int index;
40	int state;
41	int unused_only;
42	inet_prefix pfx;
43	int flushed;
44	char *flushb;
45	int flushp;
46	int flushe;
47} filter;
48
49static void usage(void) __attribute__((noreturn));
50
51static void usage(void)
52{
53	fprintf(stderr, "Usage: ip neigh { add | del | change | replace } { ADDR [ lladdr LLADDR ]\n"
54		        "          [ nud { permanent | noarp | stale | reachable } ]\n"
55		        "          | proxy ADDR } [ dev DEV ]\n");
56	fprintf(stderr, "       ip neigh {show|flush} [ to PREFIX ] [ dev DEV ] [ nud STATE ]\n");
57	exit(-1);
58}
59
60int nud_state_a2n(unsigned *state, char *arg)
61{
62	if (matches(arg, "permanent") == 0)
63		*state = NUD_PERMANENT;
64	else if (matches(arg, "reachable") == 0)
65		*state = NUD_REACHABLE;
66	else if (strcmp(arg, "noarp") == 0)
67		*state = NUD_NOARP;
68	else if (strcmp(arg, "none") == 0)
69		*state = NUD_NONE;
70	else if (strcmp(arg, "stale") == 0)
71		*state = NUD_STALE;
72	else if (strcmp(arg, "incomplete") == 0)
73		*state = NUD_INCOMPLETE;
74	else if (strcmp(arg, "delay") == 0)
75		*state = NUD_DELAY;
76	else if (strcmp(arg, "probe") == 0)
77		*state = NUD_PROBE;
78	else if (matches(arg, "failed") == 0)
79		*state = NUD_FAILED;
80	else {
81		if (get_unsigned(state, arg, 0))
82			return -1;
83		if (*state>=0x100 || (*state&((*state)-1)))
84			return -1;
85	}
86	return 0;
87}
88
89static int flush_update(void)
90{
91	if (rtnl_send(&rth, filter.flushb, filter.flushp) < 0) {
92		perror("Failed to send flush request\n");
93		return -1;
94	}
95	filter.flushp = 0;
96	return 0;
97}
98
99
100static int ipneigh_modify(int cmd, int flags, int argc, char **argv)
101{
102	struct {
103		struct nlmsghdr 	n;
104		struct ndmsg 		ndm;
105		char   			buf[256];
106	} req;
107	char  *d = NULL;
108	int dst_ok = 0;
109	int lladdr_ok = 0;
110	char * lla = NULL;
111	inet_prefix dst;
112
113	memset(&req, 0, sizeof(req));
114
115	req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg));
116	req.n.nlmsg_flags = NLM_F_REQUEST|flags;
117	req.n.nlmsg_type = cmd;
118	req.ndm.ndm_family = preferred_family;
119	req.ndm.ndm_state = NUD_PERMANENT;
120
121	while (argc > 0) {
122		if (matches(*argv, "lladdr") == 0) {
123			NEXT_ARG();
124			if (lladdr_ok)
125				duparg("lladdr", *argv);
126			lla = *argv;
127			lladdr_ok = 1;
128		} else if (strcmp(*argv, "nud") == 0) {
129			unsigned state;
130			NEXT_ARG();
131			if (nud_state_a2n(&state, *argv))
132				invarg("nud state is bad", *argv);
133			req.ndm.ndm_state = state;
134		} else if (matches(*argv, "proxy") == 0) {
135			NEXT_ARG();
136			if (matches(*argv, "help") == 0)
137				usage();
138			if (dst_ok)
139				duparg("address", *argv);
140			get_addr(&dst, *argv, preferred_family);
141			dst_ok = 1;
142			req.ndm.ndm_flags |= NTF_PROXY;
143		} else if (strcmp(*argv, "dev") == 0) {
144			NEXT_ARG();
145			d = *argv;
146		} else {
147			if (strcmp(*argv, "to") == 0) {
148				NEXT_ARG();
149			}
150			if (matches(*argv, "help") == 0) {
151				NEXT_ARG();
152			}
153			if (dst_ok)
154				duparg2("to", *argv);
155			get_addr(&dst, *argv, preferred_family);
156			dst_ok = 1;
157		}
158		argc--; argv++;
159	}
160	if (d == NULL || !dst_ok || dst.family == AF_UNSPEC) {
161		fprintf(stderr, "Device and destination are required arguments.\n");
162		exit(-1);
163	}
164	req.ndm.ndm_family = dst.family;
165	addattr_l(&req.n, sizeof(req), NDA_DST, &dst.data, dst.bytelen);
166
167	if (lla && strcmp(lla, "null")) {
168		char llabuf[16];
169		int l;
170
171		l = ll_addr_a2n(llabuf, sizeof(llabuf), lla);
172		addattr_l(&req.n, sizeof(req), NDA_LLADDR, llabuf, l);
173	}
174
175	ll_init_map(&rth);
176
177	if ((req.ndm.ndm_ifindex = ll_name_to_index(d)) == 0) {
178		fprintf(stderr, "Cannot find device \"%s\"\n", d);
179		return -1;
180	}
181
182	if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0)
183		exit(2);
184
185	return 0;
186}
187
188
189int print_neigh(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
190{
191	FILE *fp = (FILE*)arg;
192	struct ndmsg *r = NLMSG_DATA(n);
193	int len = n->nlmsg_len;
194	struct rtattr * tb[NDA_MAX+1];
195	char abuf[256];
196
197	if (n->nlmsg_type != RTM_NEWNEIGH && n->nlmsg_type != RTM_DELNEIGH) {
198		fprintf(stderr, "Not RTM_NEWNEIGH: %08x %08x %08x\n",
199			n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
200
201		return 0;
202	}
203	len -= NLMSG_LENGTH(sizeof(*r));
204	if (len < 0) {
205		fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
206		return -1;
207	}
208
209	if (filter.flushb && n->nlmsg_type != RTM_NEWNEIGH)
210		return 0;
211
212	if (filter.family && filter.family != r->ndm_family)
213		return 0;
214	if (filter.index && filter.index != r->ndm_ifindex)
215		return 0;
216	if (!(filter.state&r->ndm_state) &&
217	    (r->ndm_state || !(filter.state&0x100)) &&
218             (r->ndm_family != AF_DECnet))
219		return 0;
220
221	parse_rtattr(tb, NDA_MAX, NDA_RTA(r), n->nlmsg_len - NLMSG_LENGTH(sizeof(*r)));
222
223	if (tb[NDA_DST]) {
224		if (filter.pfx.family) {
225			inet_prefix dst;
226			memset(&dst, 0, sizeof(dst));
227			dst.family = r->ndm_family;
228			memcpy(&dst.data, RTA_DATA(tb[NDA_DST]), RTA_PAYLOAD(tb[NDA_DST]));
229			if (inet_addr_match(&dst, &filter.pfx, filter.pfx.bitlen))
230				return 0;
231		}
232	}
233	if (filter.unused_only && tb[NDA_CACHEINFO]) {
234		struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
235		if (ci->ndm_refcnt)
236			return 0;
237	}
238
239	if (filter.flushb) {
240		struct nlmsghdr *fn;
241		if (NLMSG_ALIGN(filter.flushp) + n->nlmsg_len > filter.flushe) {
242			if (flush_update())
243				return -1;
244		}
245		fn = (struct nlmsghdr*)(filter.flushb + NLMSG_ALIGN(filter.flushp));
246		memcpy(fn, n, n->nlmsg_len);
247		fn->nlmsg_type = RTM_DELNEIGH;
248		fn->nlmsg_flags = NLM_F_REQUEST;
249		fn->nlmsg_seq = ++rth.seq;
250		filter.flushp = (((char*)fn) + n->nlmsg_len) - filter.flushb;
251		filter.flushed++;
252		if (show_stats < 2)
253			return 0;
254	}
255
256	if (tb[NDA_DST]) {
257		fprintf(fp, "%s ",
258			format_host(r->ndm_family,
259				    RTA_PAYLOAD(tb[NDA_DST]),
260				    RTA_DATA(tb[NDA_DST]),
261				    abuf, sizeof(abuf)));
262	}
263	if (!filter.index && r->ndm_ifindex)
264		fprintf(fp, "dev %s ", ll_index_to_name(r->ndm_ifindex));
265	if (tb[NDA_LLADDR]) {
266		SPRINT_BUF(b1);
267		fprintf(fp, "lladdr %s", ll_addr_n2a(RTA_DATA(tb[NDA_LLADDR]),
268					      RTA_PAYLOAD(tb[NDA_LLADDR]),
269					      ll_index_to_type(r->ndm_ifindex),
270					      b1, sizeof(b1)));
271	}
272	if (r->ndm_flags & NTF_ROUTER) {
273		fprintf(fp, " router");
274	}
275	if (tb[NDA_CACHEINFO] && show_stats) {
276		static int hz;
277		struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
278		if (!hz)
279			hz = get_hz();
280		if (ci->ndm_refcnt)
281			printf(" ref %d", ci->ndm_refcnt);
282		fprintf(fp, " used %d/%d/%d", ci->ndm_used/hz,
283		       ci->ndm_confirmed/hz, ci->ndm_updated/hz);
284	}
285
286#ifdef NDA_PROBES
287	if (tb[NDA_PROBES] && show_stats) {
288		__u32 p = *(__u32 *) RTA_DATA(tb[NDA_PROBES]);
289		fprintf(fp, " probes %u", p);
290	}
291#endif
292
293	if (r->ndm_state) {
294		int nud = r->ndm_state;
295		fprintf(fp, " ");
296
297#define PRINT_FLAG(f) if (nud & NUD_##f) { \
298	nud &= ~NUD_##f; fprintf(fp, #f "%s", nud ? "," : ""); }
299		PRINT_FLAG(INCOMPLETE);
300		PRINT_FLAG(REACHABLE);
301		PRINT_FLAG(STALE);
302		PRINT_FLAG(DELAY);
303		PRINT_FLAG(PROBE);
304		PRINT_FLAG(FAILED);
305		PRINT_FLAG(NOARP);
306		PRINT_FLAG(PERMANENT);
307#undef PRINT_FLAG
308	}
309	fprintf(fp, "\n");
310
311	fflush(fp);
312	return 0;
313}
314
315void ipneigh_reset_filter()
316{
317	memset(&filter, 0, sizeof(filter));
318	filter.state = ~0;
319}
320
321int do_show_or_flush(int argc, char **argv, int flush)
322{
323	char *filter_dev = NULL;
324	int state_given = 0;
325
326	ipneigh_reset_filter();
327
328	if (!filter.family)
329		filter.family = preferred_family;
330
331	if (flush) {
332		if (argc <= 0) {
333			fprintf(stderr, "Flush requires arguments.\n");
334			return -1;
335		}
336		filter.state = ~(NUD_PERMANENT|NUD_NOARP);
337	} else
338		filter.state = 0xFF & ~NUD_NOARP;
339
340	while (argc > 0) {
341		if (strcmp(*argv, "dev") == 0) {
342			NEXT_ARG();
343			if (filter_dev)
344				duparg("dev", *argv);
345			filter_dev = *argv;
346		} else if (strcmp(*argv, "unused") == 0) {
347			filter.unused_only = 1;
348		} else if (strcmp(*argv, "nud") == 0) {
349			unsigned state;
350			NEXT_ARG();
351			if (!state_given) {
352				state_given = 1;
353				filter.state = 0;
354			}
355			if (nud_state_a2n(&state, *argv)) {
356				if (strcmp(*argv, "all") != 0)
357					invarg("nud state is bad", *argv);
358				state = ~0;
359				if (flush)
360					state &= ~NUD_NOARP;
361			}
362			if (state == 0)
363				state = 0x100;
364			filter.state |= state;
365		} else {
366			if (strcmp(*argv, "to") == 0) {
367				NEXT_ARG();
368			}
369			if (matches(*argv, "help") == 0)
370				usage();
371			get_prefix(&filter.pfx, *argv, filter.family);
372			if (filter.family == AF_UNSPEC)
373				filter.family = filter.pfx.family;
374		}
375		argc--; argv++;
376	}
377
378	ll_init_map(&rth);
379
380	if (filter_dev) {
381		if ((filter.index = ll_name_to_index(filter_dev)) == 0) {
382			fprintf(stderr, "Cannot find device \"%s\"\n", filter_dev);
383			return -1;
384		}
385	}
386
387	if (flush) {
388		int round = 0;
389		char flushb[4096-512];
390
391		filter.flushb = flushb;
392		filter.flushp = 0;
393		filter.flushe = sizeof(flushb);
394		filter.state &= ~NUD_FAILED;
395
396		while (round < MAX_ROUNDS) {
397			if (rtnl_wilddump_request(&rth, filter.family, RTM_GETNEIGH) < 0) {
398				perror("Cannot send dump request");
399				exit(1);
400			}
401			filter.flushed = 0;
402			if (rtnl_dump_filter(&rth, print_neigh, stdout, NULL, NULL) < 0) {
403				fprintf(stderr, "Flush terminated\n");
404				exit(1);
405			}
406			if (filter.flushed == 0) {
407				if (round == 0) {
408					fprintf(stderr, "Nothing to flush.\n");
409				} else if (show_stats)
410					printf("*** Flush is complete after %d round%s ***\n", round, round>1?"s":"");
411				fflush(stdout);
412				return 0;
413			}
414			round++;
415			if (flush_update() < 0)
416				exit(1);
417			if (show_stats) {
418				printf("\n*** Round %d, deleting %d entries ***\n", round, filter.flushed);
419				fflush(stdout);
420			}
421		}
422		printf("*** Flush not complete bailing out after %d rounds\n",
423			MAX_ROUNDS);
424		return 1;
425	}
426
427	if (rtnl_wilddump_request(&rth, filter.family, RTM_GETNEIGH) < 0) {
428		perror("Cannot send dump request");
429		exit(1);
430	}
431
432	if (rtnl_dump_filter(&rth, print_neigh, stdout, NULL, NULL) < 0) {
433		fprintf(stderr, "Dump terminated\n");
434		exit(1);
435	}
436
437	return 0;
438}
439
440int do_ipneigh(int argc, char **argv)
441{
442	if (argc > 0) {
443		if (matches(*argv, "add") == 0)
444			return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_EXCL, argc-1, argv+1);
445		if (matches(*argv, "change") == 0 ||
446		    strcmp(*argv, "chg") == 0)
447			return ipneigh_modify(RTM_NEWNEIGH, NLM_F_REPLACE, argc-1, argv+1);
448		if (matches(*argv, "replace") == 0)
449			return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_REPLACE, argc-1, argv+1);
450		if (matches(*argv, "delete") == 0)
451			return ipneigh_modify(RTM_DELNEIGH, 0, argc-1, argv+1);
452		if (matches(*argv, "get") == 0) {
453			fprintf(stderr, "Sorry, \"neigh get\" is not implemented :-(\n");
454			return -1;
455		}
456		if (matches(*argv, "show") == 0 ||
457		    matches(*argv, "lst") == 0 ||
458		    matches(*argv, "list") == 0)
459			return do_show_or_flush(argc-1, argv+1, 0);
460		if (matches(*argv, "flush") == 0)
461			return do_show_or_flush(argc-1, argv+1, 1);
462		if (matches(*argv, "help") == 0)
463			usage();
464	} else
465		return do_show_or_flush(0, NULL, 0);
466
467	fprintf(stderr, "Command \"%s\" is unknown, try \"ip neigh help\".\n", *argv);
468	exit(-1);
469}
470