bgpd.c revision 1.41 
1/*	$OpenBSD: bgpd.c,v 1.41 2003/12/26 21:40:40 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 *);
41int	dispatch_imsg(struct imsgbuf *, int, struct mrt_config *);
42
43int			mrtfd = -1;
44int			rfd = -1;
45volatile sig_atomic_t	mrtdump = 0;
46volatile sig_atomic_t	quit = 0;
47volatile sig_atomic_t	reconfig = 0;
48struct imsgbuf		ibuf_se;
49struct imsgbuf		ibuf_rde;
50
51void
52sighdlr(int sig)
53{
54	switch (sig) {
55	case SIGTERM:
56	case SIGINT:
57	case SIGCHLD:
58		quit = 1;
59		break;
60	case SIGHUP:
61		reconfig = 1;
62		break;
63	case SIGALRM:
64		mrtdump = 1;
65		break;
66	case SIGUSR1:
67		mrtdump = 2;
68		break;
69	}
70}
71
72void
73usage(void)
74{
75	extern char *__progname;
76
77	fprintf(stderr, "usage: %s [-dnv] ", __progname);
78	fprintf(stderr, "[-D macro=value] [-f file]\n");
79	exit(1);
80}
81
82#define POLL_MAX		8
83#define PFD_PIPE_SESSION	0
84#define PFD_PIPE_ROUTE		1
85#define PFD_SOCK_ROUTE		2
86#define PFD_MRT_START		3
87
88int
89main(int argc, char *argv[])
90{
91	struct bgpd_config	 conf;
92	struct mrt_config	 mrtconf;
93	struct mrtdump_config	*mconf, *(mrt[POLL_MAX]);
94	struct pollfd		 pfd[POLL_MAX];
95	pid_t			 io_pid = 0, rde_pid = 0;
96	char			*conffile;
97	int			 debug = 0;
98	int			 ch, i, j, n, nfds;
99	int			 pipe_m2s[2];
100	int			 pipe_m2r[2];
101	int			 pipe_s2r[2];
102
103	conffile = CONFFILE;
104	bgpd_process = PROC_MAIN;
105
106	log_init(1);		/* log to stderr until daemonized */
107
108	bzero(&conf, sizeof(conf));
109	bzero(&mrtconf, sizeof(mrtconf));
110	LIST_INIT(&mrtconf);
111
112	while ((ch = getopt(argc, argv, "dD:f:nv")) != -1) {
113		switch (ch) {
114		case 'd':
115			debug = 1;
116			break;
117		case 'D':
118			if (cmdline_symset(optarg) < 0)
119				logit(LOG_CRIT,
120				    "could not parse macro definition %s",
121				    optarg);
122			break;
123		case 'f':
124			conffile = optarg;
125			break;
126		case 'n':
127			conf.opts |= BGPD_OPT_NOACTION;
128			break;
129		case 'v':
130			if (conf.opts & BGPD_OPT_VERBOSE)
131				conf.opts |= BGPD_OPT_VERBOSE2;
132			conf.opts |= BGPD_OPT_VERBOSE;
133			break;
134		default:
135			usage();
136			/* NOTREACHED */
137		}
138	}
139
140	if (parse_config(conffile, &conf, &mrtconf))
141		exit(1);
142
143	if (conf.opts & BGPD_OPT_NOACTION) {
144		fprintf(stderr, "configuration OK\n");
145		exit(0);
146	}
147
148	if (geteuid())
149		errx(1, "need root privileges");
150
151	log_init(debug);
152
153	if (!debug)
154		daemon(1, 0);
155
156	logit(LOG_INFO, "startup");
157
158	if (pipe(pipe_m2s) == -1)
159		fatal("pipe");
160	if (fcntl(pipe_m2s[0], F_SETFL, O_NONBLOCK) == -1 ||
161	    fcntl(pipe_m2s[1], F_SETFL, O_NONBLOCK) == -1)
162		fatal("fcntl");
163	if (pipe(pipe_m2r) == -1)
164		fatal("pipe");
165	if (fcntl(pipe_m2r[0], F_SETFL, O_NONBLOCK) == -1 ||
166	    fcntl(pipe_m2r[1], F_SETFL, O_NONBLOCK) == -1)
167		fatal("fcntl");
168	if (pipe(pipe_s2r) == -1)
169		fatal("pipe");
170	if (fcntl(pipe_s2r[0], F_SETFL, O_NONBLOCK) == -1 ||
171	    fcntl(pipe_s2r[1], F_SETFL, O_NONBLOCK) == -1)
172		fatal("fcntl");
173
174	/* fork children */
175	rde_pid = rde_main(&conf, pipe_m2r, pipe_s2r);
176	io_pid = session_main(&conf, pipe_m2s, pipe_s2r);
177
178	setproctitle("parent");
179
180	signal(SIGTERM, sighdlr);
181	signal(SIGINT, sighdlr);
182	signal(SIGCHLD, sighdlr);
183	signal(SIGHUP, sighdlr);
184	signal(SIGALRM, sighdlr);
185	signal(SIGUSR1, sighdlr);
186
187	close(pipe_m2s[1]);
188	close(pipe_m2r[1]);
189	close(pipe_s2r[0]);
190	close(pipe_s2r[1]);
191
192	imsg_init(&ibuf_se, pipe_m2s[0]);
193	imsg_init(&ibuf_rde, pipe_m2r[0]);
194	if ((rfd = kroute_init()) == -1)
195		quit = 1;
196
197	while (quit == 0) {
198		pfd[PFD_PIPE_SESSION].fd = ibuf_se.sock;
199		pfd[PFD_PIPE_SESSION].events = POLLIN;
200		if (ibuf_se.w.queued)
201			pfd[PFD_PIPE_SESSION].events |= POLLOUT;
202		pfd[PFD_PIPE_ROUTE].fd = ibuf_rde.sock;
203		pfd[PFD_PIPE_ROUTE].events = POLLIN;
204		if (ibuf_rde.w.queued)
205			pfd[PFD_PIPE_ROUTE].events |= POLLOUT;
206		pfd[PFD_SOCK_ROUTE].fd = rfd;
207		pfd[PFD_SOCK_ROUTE].events = POLLIN;
208		i = PFD_MRT_START;
209		LIST_FOREACH(mconf, &mrtconf, list)
210			if (mconf->msgbuf.queued > 0) {
211				pfd[i].fd = mconf->msgbuf.sock;
212				pfd[i].events |= POLLOUT;
213				mrt[i++] = mconf;
214			}
215
216		if ((nfds = poll(pfd, i, INFTIM)) == -1)
217			if (errno != EINTR) {
218				log_err("poll error");
219				quit = 1;
220			}
221
222		if (nfds > 0 && (pfd[PFD_PIPE_SESSION].revents & POLLOUT))
223			if ((n = msgbuf_write(&ibuf_se.w)) < 0) {
224				log_err("pipe write error (to SE)");
225				quit = 1;
226			}
227
228		if (nfds > 0 && (pfd[PFD_PIPE_ROUTE].revents & POLLOUT))
229			if ((n = msgbuf_write(&ibuf_rde.w)) < 0) {
230				log_err("pipe write error (to RDE)");
231				quit = 1;
232			}
233
234		if (nfds > 0 && pfd[PFD_PIPE_SESSION].revents & POLLIN) {
235			nfds--;
236			if (dispatch_imsg(&ibuf_se, PFD_PIPE_SESSION,
237			    &mrtconf) == -1)
238				quit = 1;
239		}
240
241		if (nfds > 0 && pfd[PFD_PIPE_ROUTE].revents & POLLIN) {
242			nfds--;
243			if (dispatch_imsg(&ibuf_rde, PFD_PIPE_ROUTE,
244			    &mrtconf) == -1)
245				quit = 1;
246		}
247
248		if (nfds > 0 && pfd[PFD_SOCK_ROUTE].revents & POLLIN) {
249			nfds--;
250			if (kroute_dispatch_msg(rfd) == -1)
251				quit = 1;
252		}
253
254		for (j = PFD_MRT_START; j < i && nfds > 0 ; j++) {
255			if (pfd[j].revents & POLLOUT) {
256				if ((n = msgbuf_write(&mrt[i]->msgbuf)) < 0) {
257					log_err("pipe write error (MRT)");
258					quit = 1;
259				}
260			}
261		}
262
263		if (reconfig) {
264			logit(LOG_CRIT, "rereading config");
265			reconfigure(conffile, &conf, &mrtconf);
266			LIST_FOREACH(mconf, &mrtconf, list)
267				mrt_state(mconf, IMSG_NONE, &ibuf_rde);
268			reconfig = 0;
269		}
270
271		if (mrtdump == 1) {
272			mrt_alrm(&mrtconf, &ibuf_rde);
273			mrtdump = 0;
274		} else if (mrtdump == 2) {
275			mrt_usr1(&mrtconf, &ibuf_rde);
276			mrtdump = 0;
277		}
278	}
279
280	signal(SIGCHLD, SIG_IGN);
281
282	if (io_pid)
283		kill(io_pid, SIGTERM);
284
285	if (rde_pid)
286		kill(rde_pid, SIGTERM);
287
288	do {
289		i = waitpid(-1, NULL, WNOHANG);
290	} while (i > 0 || (i == -1 && errno == EINTR));
291
292	kroute_shutdown(rfd);
293
294	logit(LOG_CRIT, "Terminating");
295	return (0);
296}
297
298int
299reconfigure(char *conffile, struct bgpd_config *conf, struct mrt_config *mrtc)
300{
301	struct peer		*p;
302
303	if (parse_config(conffile, conf, mrtc)) {
304		logit(LOG_CRIT, "config file %s has errors, not reloading",
305		    conffile);
306		return (-1);
307	}
308	if (imsg_compose(&ibuf_se, IMSG_RECONF_CONF, 0,
309	    conf, sizeof(struct bgpd_config)) == -1)
310		return (-1);
311	if (imsg_compose(&ibuf_rde, IMSG_RECONF_CONF, 0,
312	    conf, sizeof(struct bgpd_config)) == -1)
313		return (-1);
314	for (p = conf->peers; p != NULL; p = p->next) {
315		if (imsg_compose(&ibuf_se, IMSG_RECONF_PEER, p->conf.id,
316		    &p->conf, sizeof(struct peer_config)) == -1)
317			return (-1);
318		if (imsg_compose(&ibuf_rde, IMSG_RECONF_PEER, p->conf.id,
319		    &p->conf, sizeof(struct peer_config)) == -1)
320			return (-1);
321	}
322	if (imsg_compose(&ibuf_se, IMSG_RECONF_DONE, 0, NULL, 0) == -1 ||
323	    imsg_compose(&ibuf_rde, IMSG_RECONF_DONE, 0, NULL, 0) == -1)
324		return (-1);
325
326	return (0);
327}
328
329/*
330 * XXX currently messages are only buffered for mrt files.
331 */
332int
333dispatch_imsg(struct imsgbuf *ibuf, int idx, struct mrt_config *conf)
334{
335	struct imsg		 imsg;
336	struct buf		*wbuf;
337	struct mrtdump_config	*m;
338	ssize_t			 len;
339	int			 n;
340	in_addr_t		 ina;
341
342	if ((n = imsg_get(ibuf, &imsg)) == -1)
343		return (-1);
344
345	if (n > 0) {
346		switch (imsg.hdr.type) {
347		case IMSG_MRT_MSG:
348		case IMSG_MRT_END:
349			LIST_FOREACH(m, conf, list) {
350				if (m->id != imsg.hdr.peerid)
351					continue;
352				if (mrt_state(m, imsg.hdr.type, ibuf) == 0)
353					break;
354				if (m->msgbuf.sock == -1)
355					break;
356				len = imsg.hdr.len - IMSG_HEADER_SIZE;
357				wbuf = buf_open(len);
358				if (wbuf == NULL)
359					return (-1);
360				if (buf_add(wbuf, imsg.data, len) == -1)
361					return (-1);
362				if ((n = buf_close(&m->msgbuf, wbuf)) < 0)
363					return (-1);
364				break;
365			}
366			break;
367		case IMSG_KROUTE_CHANGE:
368			if (idx != PFD_PIPE_ROUTE)
369				logit(LOG_CRIT, "route request not from RDE");
370			else if (kroute_change(rfd, imsg.data))
371				return (-1);
372			break;
373		case IMSG_KROUTE_DELETE:
374			if (idx != PFD_PIPE_ROUTE)
375				logit(LOG_CRIT, "route request not from RDE");
376			else if (kroute_delete(rfd, imsg.data))
377				return (-1);
378			break;
379		case IMSG_NEXTHOP_ADD:
380			if (idx != PFD_PIPE_ROUTE)
381				logit(LOG_CRIT, "nexthop request not from RDE");
382			else {
383				memcpy(&ina, imsg.data, sizeof(ina));
384				if (kroute_nexthop_add(ina) == -1)
385					return (-1);
386			}
387			break;
388		case IMSG_NEXTHOP_REMOVE:
389			if (idx != PFD_PIPE_ROUTE)
390				logit(LOG_CRIT, "nexthop request not from RDE");
391			else {
392				memcpy(&ina, imsg.data, sizeof(ina));
393				kroute_nexthop_delete(ina);
394			}
395			break;
396		default:
397			break;
398		}
399		imsg_free(&imsg);
400	}
401	return (0);
402}
403
404void
405send_nexthop_update(struct kroute_nexthop *msg)
406{
407	char	*gw = NULL;
408
409	if (msg->gateway)
410		if (asprintf(&gw, ": via %s", log_ntoa(msg->gateway)) == -1) {
411			log_err("send_nexthop_update");
412			quit = 1;
413		}
414
415	logit(LOG_INFO, "nexthop %s now %s%s%s", log_ntoa(msg->nexthop),
416	    msg->valid ? "valid" : "invalid",
417	    msg->connected ? ": directly connected" : "",
418	    msg->gateway ? gw : "");
419
420	free(gw);
421
422	if (imsg_compose(&ibuf_rde, IMSG_NEXTHOP_UPDATE, 0,
423	    msg, sizeof(struct kroute_nexthop)) == -1)
424		quit = 1;
425}
426