bgpd.c revision 1.51 
1/*	$OpenBSD: bgpd.c,v 1.51 2004/01/03 20:22:07 henning Exp $ */
2
3/*
4 * Copyright (c) 2003 Henning Brauer <henning@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19#include <sys/types.h>
20#include <sys/socket.h>
21#include <sys/wait.h>
22#include <netinet/in.h>
23#include <arpa/inet.h>
24#include <err.h>
25#include <errno.h>
26#include <fcntl.h>
27#include <poll.h>
28#include <signal.h>
29#include <stdio.h>
30#include <stdlib.h>
31#include <string.h>
32#include <unistd.h>
33
34#include "mrt.h"
35#include "bgpd.h"
36
37void	sighdlr(int);
38void	usage(void);
39int	main(int, char *[]);
40int	reconfigure(char *, struct bgpd_config *, struct mrt_config *,
41	    struct peer *);
42int	dispatch_imsg(struct imsgbuf *, int, struct mrt_config *);
43
44int			mrtfd = -1;
45int			rfd = -1;
46volatile sig_atomic_t	mrtdump = 0;
47volatile sig_atomic_t	quit = 0;
48volatile sig_atomic_t	reconfig = 0;
49struct imsgbuf		ibuf_se;
50struct imsgbuf		ibuf_rde;
51
52void
53sighdlr(int sig)
54{
55	switch (sig) {
56	case SIGTERM:
57	case SIGINT:
58	case SIGCHLD:
59		quit = 1;
60		break;
61	case SIGHUP:
62		reconfig = 1;
63		break;
64	case SIGALRM:
65		mrtdump = 1;
66		break;
67	case SIGUSR1:
68		mrtdump = 2;
69		break;
70	}
71}
72
73void
74usage(void)
75{
76	extern char *__progname;
77
78	fprintf(stderr, "usage: %s [-dnv] ", __progname);
79	fprintf(stderr, "[-D macro=value] [-f file]\n");
80	exit(1);
81}
82
83#define POLL_MAX		8
84#define PFD_PIPE_SESSION	0
85#define PFD_PIPE_ROUTE		1
86#define PFD_SOCK_ROUTE		2
87#define PFD_MRT_START		3
88
89int
90main(int argc, char *argv[])
91{
92	struct bgpd_config	 conf;
93	struct peer		*peers, *p, *next;
94	struct mrt_config	 mrtconf;
95	struct mrtdump_config	*mconf, *(mrt[POLL_MAX]);
96	struct pollfd		 pfd[POLL_MAX];
97	pid_t			 io_pid = 0, rde_pid = 0;
98	char			*conffile;
99	int			 debug = 0;
100	int			 ch, i, j, n, nfds, csock;
101	int			 pipe_m2s[2];
102	int			 pipe_m2r[2];
103	int			 pipe_s2r[2];
104
105	conffile = CONFFILE;
106	bgpd_process = PROC_MAIN;
107
108	log_init(1);		/* log to stderr until daemonized */
109
110	bzero(&conf, sizeof(conf));
111	bzero(&mrtconf, sizeof(mrtconf));
112	LIST_INIT(&mrtconf);
113	peers = NULL;
114
115	while ((ch = getopt(argc, argv, "dD:f:nv")) != -1) {
116		switch (ch) {
117		case 'd':
118			debug = 1;
119			break;
120		case 'D':
121			if (cmdline_symset(optarg) < 0)
122				logit(LOG_CRIT,
123				    "could not parse macro definition %s",
124				    optarg);
125			break;
126		case 'f':
127			conffile = optarg;
128			break;
129		case 'n':
130			conf.opts |= BGPD_OPT_NOACTION;
131			break;
132		case 'v':
133			if (conf.opts & BGPD_OPT_VERBOSE)
134				conf.opts |= BGPD_OPT_VERBOSE2;
135			conf.opts |= BGPD_OPT_VERBOSE;
136			break;
137		default:
138			usage();
139			/* NOTREACHED */
140		}
141	}
142
143	if (parse_config(conffile, &conf, &mrtconf, &peers))
144		exit(1);
145
146	if (conf.opts & BGPD_OPT_NOACTION) {
147		fprintf(stderr, "configuration OK\n");
148		exit(0);
149	}
150
151	if (geteuid())
152		errx(1, "need root privileges");
153
154	log_init(debug);
155
156	if (!debug)
157		daemon(1, 0);
158
159	logit(LOG_INFO, "startup");
160
161	if (pipe(pipe_m2s) == -1)
162		fatal("pipe");
163	if (fcntl(pipe_m2s[0], F_SETFL, O_NONBLOCK) == -1 ||
164	    fcntl(pipe_m2s[1], F_SETFL, O_NONBLOCK) == -1)
165		fatal("fcntl");
166	if (pipe(pipe_m2r) == -1)
167		fatal("pipe");
168	if (fcntl(pipe_m2r[0], F_SETFL, O_NONBLOCK) == -1 ||
169	    fcntl(pipe_m2r[1], F_SETFL, O_NONBLOCK) == -1)
170		fatal("fcntl");
171	if (pipe(pipe_s2r) == -1)
172		fatal("pipe");
173	if (fcntl(pipe_s2r[0], F_SETFL, O_NONBLOCK) == -1 ||
174	    fcntl(pipe_s2r[1], F_SETFL, O_NONBLOCK) == -1)
175		fatal("fcntl");
176
177	if ((csock = control_init()) == -1)
178		fatalx("control socket setup failed");
179
180	/* fork children */
181	rde_pid = rde_main(&conf, peers, pipe_m2r, pipe_s2r);
182	io_pid = session_main(&conf, peers, pipe_m2s, pipe_s2r);
183
184	setproctitle("parent");
185
186	signal(SIGTERM, sighdlr);
187	signal(SIGINT, sighdlr);
188	signal(SIGCHLD, sighdlr);
189	signal(SIGHUP, sighdlr);
190	signal(SIGALRM, sighdlr);
191	signal(SIGUSR1, sighdlr);
192
193	close(pipe_m2s[1]);
194	close(pipe_m2r[1]);
195	close(pipe_s2r[0]);
196	close(pipe_s2r[1]);
197	close(csock);
198
199	imsg_init(&ibuf_se, pipe_m2s[0]);
200	imsg_init(&ibuf_rde, pipe_m2r[0]);
201	if ((rfd = kroute_init(!(conf.flags & BGPD_FLAG_NO_FIB_UPDATE))) == -1)
202		quit = 1;
203
204	for (p = peers; p != NULL; p = next) {
205		next = p->next;
206		free(p);
207	}
208
209	while (quit == 0) {
210		pfd[PFD_PIPE_SESSION].fd = ibuf_se.sock;
211		pfd[PFD_PIPE_SESSION].events = POLLIN;
212		if (ibuf_se.w.queued)
213			pfd[PFD_PIPE_SESSION].events |= POLLOUT;
214		pfd[PFD_PIPE_ROUTE].fd = ibuf_rde.sock;
215		pfd[PFD_PIPE_ROUTE].events = POLLIN;
216		if (ibuf_rde.w.queued)
217			pfd[PFD_PIPE_ROUTE].events |= POLLOUT;
218		pfd[PFD_SOCK_ROUTE].fd = rfd;
219		pfd[PFD_SOCK_ROUTE].events = POLLIN;
220		i = PFD_MRT_START;
221		LIST_FOREACH(mconf, &mrtconf, list)
222			if (mconf->msgbuf.queued > 0) {
223				pfd[i].fd = mconf->msgbuf.sock;
224				pfd[i].events |= POLLOUT;
225				mrt[i++] = mconf;
226			}
227
228		if ((nfds = poll(pfd, i, INFTIM)) == -1)
229			if (errno != EINTR) {
230				log_err("poll error");
231				quit = 1;
232			}
233
234		if (nfds > 0 && (pfd[PFD_PIPE_SESSION].revents & POLLOUT))
235			if ((n = msgbuf_write(&ibuf_se.w)) < 0) {
236				log_err("pipe write error (to SE)");
237				quit = 1;
238			}
239
240		if (nfds > 0 && (pfd[PFD_PIPE_ROUTE].revents & POLLOUT))
241			if ((n = msgbuf_write(&ibuf_rde.w)) < 0) {
242				log_err("pipe write error (to RDE)");
243				quit = 1;
244			}
245
246		if (nfds > 0 && pfd[PFD_PIPE_SESSION].revents & POLLIN) {
247			nfds--;
248			if (dispatch_imsg(&ibuf_se, PFD_PIPE_SESSION,
249			    &mrtconf) == -1)
250				quit = 1;
251		}
252
253		if (nfds > 0 && pfd[PFD_PIPE_ROUTE].revents & POLLIN) {
254			nfds--;
255			if (dispatch_imsg(&ibuf_rde, PFD_PIPE_ROUTE,
256			    &mrtconf) == -1)
257				quit = 1;
258		}
259
260		if (nfds > 0 && pfd[PFD_SOCK_ROUTE].revents & POLLIN) {
261			nfds--;
262			if (kroute_dispatch_msg() == -1)
263				quit = 1;
264		}
265
266		for (j = PFD_MRT_START; j < i && nfds > 0 ; j++) {
267			if (pfd[j].revents & POLLOUT) {
268				if ((n = msgbuf_write(&mrt[i]->msgbuf)) < 0) {
269					log_err("pipe write error (MRT)");
270					quit = 1;
271				}
272			}
273		}
274
275		if (reconfig) {
276			logit(LOG_CRIT, "rereading config");
277			reconfigure(conffile, &conf, &mrtconf, peers);
278			LIST_FOREACH(mconf, &mrtconf, list)
279				mrt_state(mconf, IMSG_NONE, &ibuf_rde);
280			reconfig = 0;
281		}
282
283		if (mrtdump == 1) {
284			mrt_alrm(&mrtconf, &ibuf_rde);
285			mrtdump = 0;
286		} else if (mrtdump == 2) {
287			mrt_usr1(&mrtconf, &ibuf_rde);
288			mrtdump = 0;
289		}
290	}
291
292	signal(SIGCHLD, SIG_IGN);
293
294	if (io_pid)
295		kill(io_pid, SIGTERM);
296
297	if (rde_pid)
298		kill(rde_pid, SIGTERM);
299
300	do {
301		i = waitpid(-1, NULL, WNOHANG);
302	} while (i > 0 || (i == -1 && errno == EINTR));
303
304	control_cleanup();
305	kroute_shutdown();
306
307	logit(LOG_CRIT, "Terminating");
308	return (0);
309}
310
311int
312reconfigure(char *conffile, struct bgpd_config *conf, struct mrt_config *mrtc,
313    struct peer *peers)
314{
315	struct peer		*p, *next;
316
317	if (parse_config(conffile, conf, mrtc, &peers)) {
318		logit(LOG_CRIT, "config file %s has errors, not reloading",
319		    conffile);
320		return (-1);
321	}
322
323	if (imsg_compose(&ibuf_se, IMSG_RECONF_CONF, 0,
324	    conf, sizeof(struct bgpd_config)) == -1)
325		return (-1);
326	if (imsg_compose(&ibuf_rde, IMSG_RECONF_CONF, 0,
327	    conf, sizeof(struct bgpd_config)) == -1)
328		return (-1);
329	for (p = peers; p != NULL; p = next) {
330		next = p->next;
331		if (imsg_compose(&ibuf_se, IMSG_RECONF_PEER, p->conf.id,
332		    &p->conf, sizeof(struct peer_config)) == -1)
333			return (-1);
334		if (imsg_compose(&ibuf_rde, IMSG_RECONF_PEER, p->conf.id,
335		    &p->conf, sizeof(struct peer_config)) == -1)
336			return (-1);
337		free(p);
338	}
339	if (imsg_compose(&ibuf_se, IMSG_RECONF_DONE, 0, NULL, 0) == -1 ||
340	    imsg_compose(&ibuf_rde, IMSG_RECONF_DONE, 0, NULL, 0) == -1)
341		return (-1);
342
343	return (0);
344}
345
346/*
347 * XXX currently messages are only buffered for mrt files.
348 */
349int
350dispatch_imsg(struct imsgbuf *ibuf, int idx, struct mrt_config *conf)
351{
352	struct imsg		 imsg;
353	struct buf		*wbuf;
354	struct mrtdump_config	*m;
355	ssize_t			 len;
356	int			 n;
357	in_addr_t		 ina;
358
359	if ((n = imsg_read(ibuf)) == -1)
360		return (-1);
361
362	if (n == 0) {	/* connection closed */
363		logit(LOG_CRIT, "dispatch_imsg in main: pipe closed");
364		return (-1);
365	}
366
367	for (;;) {
368		if ((n = imsg_get(ibuf, &imsg)) == -1)
369			return (-1);
370
371		if (n == 0)
372			break;
373
374		switch (imsg.hdr.type) {
375		case IMSG_MRT_MSG:
376		case IMSG_MRT_END:
377			LIST_FOREACH(m, conf, list) {
378				if (m->id != imsg.hdr.peerid)
379					continue;
380				if (mrt_state(m, imsg.hdr.type, ibuf) == 0)
381					break;
382				if (m->msgbuf.sock == -1)
383					break;
384				len = imsg.hdr.len - IMSG_HEADER_SIZE;
385				wbuf = buf_open(len);
386				if (wbuf == NULL)
387					return (-1);
388				if (buf_add(wbuf, imsg.data, len) == -1) {
389					buf_free(wbuf);
390					return (-1);
391				}
392				if ((n = buf_close(&m->msgbuf, wbuf)) < 0) {
393					buf_free(wbuf);
394					return (-1);
395				}
396				break;
397			}
398			break;
399		case IMSG_KROUTE_CHANGE:
400			if (idx != PFD_PIPE_ROUTE)
401				logit(LOG_CRIT, "route request not from RDE");
402			else if (kroute_change(imsg.data))
403				return (-1);
404			break;
405		case IMSG_KROUTE_DELETE:
406			if (idx != PFD_PIPE_ROUTE)
407				logit(LOG_CRIT, "route request not from RDE");
408			else if (kroute_delete(imsg.data))
409				return (-1);
410			break;
411		case IMSG_NEXTHOP_ADD:
412			if (idx != PFD_PIPE_ROUTE)
413				logit(LOG_CRIT, "nexthop request not from RDE");
414			else {
415				memcpy(&ina, imsg.data, sizeof(ina));
416				if (kroute_nexthop_add(ina) == -1)
417					return (-1);
418			}
419			break;
420		case IMSG_NEXTHOP_REMOVE:
421			if (idx != PFD_PIPE_ROUTE)
422				logit(LOG_CRIT, "nexthop request not from RDE");
423			else {
424				memcpy(&ina, imsg.data, sizeof(ina));
425				kroute_nexthop_delete(ina);
426			}
427			break;
428		default:
429			break;
430		}
431		imsg_free(&imsg);
432	}
433	return (0);
434}
435
436void
437send_nexthop_update(struct kroute_nexthop *msg)
438{
439	char	*gw = NULL;
440
441	if (msg->gateway)
442		if (asprintf(&gw, ": via %s", log_ntoa(msg->gateway)) == -1) {
443			log_err("send_nexthop_update");
444			quit = 1;
445		}
446
447	logit(LOG_INFO, "nexthop %s now %s%s%s", log_ntoa(msg->nexthop),
448	    msg->valid ? "valid" : "invalid",
449	    msg->connected ? ": directly connected" : "",
450	    msg->gateway ? gw : "");
451
452	free(gw);
453
454	if (imsg_compose(&ibuf_rde, IMSG_NEXTHOP_UPDATE, 0,
455	    msg, sizeof(struct kroute_nexthop)) == -1)
456		quit = 1;
457}
458