bgpd.c revision 1.68 
1/*	$OpenBSD: bgpd.c,v 1.68 2004/01/17 19:35:35 claudio Exp $ */
2
3/*
4 * Copyright (c) 2003, 2004 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#include "session.h"
37
38void	sighdlr(int);
39void	usage(void);
40int	main(int, char *[]);
41int	check_child(pid_t, const char *);
42int	reconfigure(char *, struct bgpd_config *, struct mrt_head *,
43	    struct peer *);
44int	dispatch_imsg(struct imsgbuf *, int, struct mrt_head *);
45
46int			rfd = -1;
47volatile sig_atomic_t	mrtdump = 0;
48volatile sig_atomic_t	quit = 0;
49volatile sig_atomic_t	reconfig = 0;
50volatile sig_atomic_t	sigchld = 0;
51struct imsgbuf		ibuf_se;
52struct imsgbuf		ibuf_rde;
53
54void
55sighdlr(int sig)
56{
57	switch (sig) {
58	case SIGTERM:
59	case SIGINT:
60		quit = 1;
61		break;
62	case SIGCHLD:
63		sigchld = 1;
64		break;
65	case SIGHUP:
66		reconfig = 1;
67		break;
68	case SIGALRM:
69	case SIGUSR1:
70		mrtdump = 1;
71		break;
72	}
73}
74
75void
76usage(void)
77{
78	extern char *__progname;
79
80	fprintf(stderr, "usage: %s [-dnv] ", __progname);
81	fprintf(stderr, "[-D macro=value] [-f file]\n");
82	exit(1);
83}
84
85#define POLL_MAX		8
86#define PFD_PIPE_SESSION	0
87#define PFD_PIPE_ROUTE		1
88#define PFD_SOCK_ROUTE		2
89#define PFD_MRT_START		3
90
91int
92main(int argc, char *argv[])
93{
94	struct bgpd_config	 conf;
95	struct peer		*peer_l, *p, *next;
96	struct mrt_head		 mrt_l;
97	struct network_head	 net_l;
98	struct network		*net;
99	struct mrt		*(mrt[POLL_MAX]);
100	struct pollfd		 pfd[POLL_MAX];
101	pid_t			 io_pid = 0, rde_pid = 0, pid;
102	char			*conffile;
103	int			 debug = 0;
104	int			 ch, csock, i, j, n, nfds, timeout;
105	int			 pipe_m2s[2];
106	int			 pipe_m2r[2];
107	int			 pipe_s2r[2];
108
109	conffile = CONFFILE;
110	bgpd_process = PROC_MAIN;
111
112	log_init(1);		/* log to stderr until daemonized */
113
114	bzero(&conf, sizeof(conf));
115	LIST_INIT(&mrt_l);
116	TAILQ_INIT(&net_l);
117	peer_l = NULL;
118
119	while ((ch = getopt(argc, argv, "dD:f:nv")) != -1) {
120		switch (ch) {
121		case 'd':
122			debug = 1;
123			break;
124		case 'D':
125			if (cmdline_symset(optarg) < 0)
126				logit(LOG_CRIT,
127				    "could not parse macro definition %s",
128				    optarg);
129			break;
130		case 'f':
131			conffile = optarg;
132			break;
133		case 'n':
134			conf.opts |= BGPD_OPT_NOACTION;
135			break;
136		case 'v':
137			if (conf.opts & BGPD_OPT_VERBOSE)
138				conf.opts |= BGPD_OPT_VERBOSE2;
139			conf.opts |= BGPD_OPT_VERBOSE;
140			break;
141		default:
142			usage();
143			/* NOTREACHED */
144		}
145	}
146
147	if (parse_config(conffile, &conf, &mrt_l, &peer_l, &net_l))
148		exit(1);
149
150	if (conf.opts & BGPD_OPT_NOACTION) {
151		fprintf(stderr, "configuration OK\n");
152		exit(0);
153	}
154
155	if (geteuid())
156		errx(1, "need root privileges");
157
158	log_init(debug);
159
160	if (!debug)
161		daemon(1, 0);
162
163	logit(LOG_INFO, "startup");
164
165	if (pipe(pipe_m2s) == -1)
166		fatal("pipe");
167	if (fcntl(pipe_m2s[0], F_SETFL, O_NONBLOCK) == -1 ||
168	    fcntl(pipe_m2s[1], F_SETFL, O_NONBLOCK) == -1)
169		fatal("fcntl");
170	if (pipe(pipe_m2r) == -1)
171		fatal("pipe");
172	if (fcntl(pipe_m2r[0], F_SETFL, O_NONBLOCK) == -1 ||
173	    fcntl(pipe_m2r[1], F_SETFL, O_NONBLOCK) == -1)
174		fatal("fcntl");
175	if (pipe(pipe_s2r) == -1)
176		fatal("pipe");
177	if (fcntl(pipe_s2r[0], F_SETFL, O_NONBLOCK) == -1 ||
178	    fcntl(pipe_s2r[1], F_SETFL, O_NONBLOCK) == -1)
179		fatal("fcntl");
180
181	if ((csock = control_init()) == -1)
182		fatalx("control socket setup failed");
183
184	/* fork children */
185	rde_pid = rde_main(&conf, peer_l, &net_l, pipe_m2r, pipe_s2r);
186	io_pid = session_main(&conf, peer_l, pipe_m2s, pipe_s2r);
187
188	setproctitle("parent");
189
190	signal(SIGTERM, sighdlr);
191	signal(SIGINT, sighdlr);
192	signal(SIGCHLD, sighdlr);
193	signal(SIGHUP, sighdlr);
194	signal(SIGALRM, sighdlr);
195	signal(SIGUSR1, sighdlr);
196
197	close(pipe_m2s[1]);
198	close(pipe_m2r[1]);
199	close(pipe_s2r[0]);
200	close(pipe_s2r[1]);
201	close(csock);
202
203	imsg_init(&ibuf_se, pipe_m2s[0]);
204	imsg_init(&ibuf_rde, pipe_m2r[0]);
205	mrt_init(&ibuf_rde, &ibuf_se);
206	if ((rfd = kr_init(!(conf.flags & BGPD_FLAG_NO_FIB_UPDATE))) == -1)
207		quit = 1;
208
209	for (p = peer_l; p != NULL; p = next) {
210		next = p->next;
211		free(p);
212	}
213	for (net = TAILQ_FIRST(&net_l); net != TAILQ_END(&net_l);
214	    net = TAILQ_FIRST(&net_l)) {
215		TAILQ_REMOVE(&net_l, net, network_l);
216		free(net);
217	}
218
219	while (quit == 0) {
220		pfd[PFD_PIPE_SESSION].fd = ibuf_se.sock;
221		pfd[PFD_PIPE_SESSION].events = POLLIN;
222		if (ibuf_se.w.queued)
223			pfd[PFD_PIPE_SESSION].events |= POLLOUT;
224		pfd[PFD_PIPE_ROUTE].fd = ibuf_rde.sock;
225		pfd[PFD_PIPE_ROUTE].events = POLLIN;
226		if (ibuf_rde.w.queued)
227			pfd[PFD_PIPE_ROUTE].events |= POLLOUT;
228		pfd[PFD_SOCK_ROUTE].fd = rfd;
229		pfd[PFD_SOCK_ROUTE].events = POLLIN;
230		i = PFD_MRT_START;
231		i = mrt_select(&mrt_l, pfd, mrt, i, POLL_MAX, &timeout);
232
233		if ((nfds = poll(pfd, i, INFTIM)) == -1)
234			if (errno != EINTR) {
235				log_err("poll error");
236				quit = 1;
237			}
238
239		if (nfds > 0 && (pfd[PFD_PIPE_SESSION].revents & POLLOUT))
240			if ((n = msgbuf_write(&ibuf_se.w)) < 0) {
241				log_err("pipe write error (to SE)");
242				quit = 1;
243			}
244
245		if (nfds > 0 && (pfd[PFD_PIPE_ROUTE].revents & POLLOUT))
246			if ((n = msgbuf_write(&ibuf_rde.w)) < 0) {
247				log_err("pipe write error (to RDE)");
248				quit = 1;
249			}
250
251		if (nfds > 0 && pfd[PFD_PIPE_SESSION].revents & POLLIN) {
252			nfds--;
253			if (dispatch_imsg(&ibuf_se, PFD_PIPE_SESSION,
254			    &mrt_l) == -1)
255				quit = 1;
256		}
257
258		if (nfds > 0 && pfd[PFD_PIPE_ROUTE].revents & POLLIN) {
259			nfds--;
260			if (dispatch_imsg(&ibuf_rde, PFD_PIPE_ROUTE,
261			    &mrt_l) == -1)
262				quit = 1;
263		}
264
265		if (nfds > 0 && pfd[PFD_SOCK_ROUTE].revents & POLLIN) {
266			nfds--;
267			if (kr_dispatch_msg() == -1)
268				quit = 1;
269		}
270
271		for (j = PFD_MRT_START; j < i && nfds > 0 ; j++) {
272			if (pfd[j].revents & POLLOUT) {
273				if ((n = mrt_write(mrt[j])) < 0) {
274					log_err("mrt write error");
275				}
276			}
277		}
278
279		if (reconfig) {
280			logit(LOG_CRIT, "rereading config");
281			reconfigure(conffile, &conf, &mrt_l, peer_l);
282			reconfig = 0;
283		}
284
285		if (sigchld) {
286			if (check_child(io_pid, "session engine"))
287				quit = 1;
288			if (check_child(rde_pid, "route decision engine"))
289				quit = 1;
290			sigchld = 0;
291		}
292
293		if (mrtdump == 1) {
294			mrt_handler(&mrt_l);
295			mrtdump = 0;
296		}
297	}
298
299	signal(SIGCHLD, SIG_IGN);
300
301	if (io_pid)
302		kill(io_pid, SIGTERM);
303
304	if (rde_pid)
305		kill(rde_pid, SIGTERM);
306
307	do {
308		pid = waitpid(-1, NULL, WNOHANG);
309	} while (pid > 0 || (pid == -1 && errno == EINTR));
310
311	control_cleanup();
312	kr_shutdown();
313
314	logit(LOG_CRIT, "Terminating");
315	return (0);
316}
317
318int
319check_child(pid_t pid, const char *pname)
320{
321	int	status;
322
323	if (waitpid(pid, &status, WNOHANG) > 0) {
324		if (WIFEXITED(status)) {
325			logit(LOG_CRIT, "Lost child: %s exited", pname);
326			return (1);
327		}
328		if (WIFSIGNALED(status)) {
329			logit(LOG_CRIT, "Lost child: %s terminated; signal %d",
330			    pname, WTERMSIG(status));
331			return (1);
332		}
333	}
334
335	return (0);
336}
337
338int
339reconfigure(char *conffile, struct bgpd_config *conf, struct mrt_head *mrt_l,
340    struct peer *peer_l)
341{
342	struct network_head	 net_l;
343	struct network		*n;
344	struct peer		*p, *next;
345
346	if (parse_config(conffile, conf, mrt_l, &peer_l, &net_l)) {
347		logit(LOG_CRIT, "config file %s has errors, not reloading",
348		    conffile);
349		return (-1);
350	}
351
352	if (imsg_compose(&ibuf_se, IMSG_RECONF_CONF, 0,
353	    conf, sizeof(struct bgpd_config)) == -1)
354		return (-1);
355	if (imsg_compose(&ibuf_rde, IMSG_RECONF_CONF, 0,
356	    conf, sizeof(struct bgpd_config)) == -1)
357		return (-1);
358	for (p = peer_l; p != NULL; p = next) {
359		next = p->next;
360		if (imsg_compose(&ibuf_se, IMSG_RECONF_PEER, p->conf.id,
361		    &p->conf, sizeof(struct peer_config)) == -1)
362			return (-1);
363		if (imsg_compose(&ibuf_rde, IMSG_RECONF_PEER, p->conf.id,
364		    &p->conf, sizeof(struct peer_config)) == -1)
365			return (-1);
366		free(p);
367	}
368	for (n = TAILQ_FIRST(&net_l); n != TAILQ_END(&net_l);
369	    n = TAILQ_FIRST(&net_l)) {
370		if (imsg_compose(&ibuf_rde, IMSG_RECONF_NETWORK, 0,
371		    &n->net, sizeof(struct network_config)) == -1)
372			return (-1);
373		TAILQ_REMOVE(&net_l, n, network_l);
374		free(n);
375	}
376	if (imsg_compose(&ibuf_se, IMSG_RECONF_DONE, 0, NULL, 0) == -1 ||
377	    imsg_compose(&ibuf_rde, IMSG_RECONF_DONE, 0, NULL, 0) == -1)
378		return (-1);
379
380	return (0);
381}
382
383int
384dispatch_imsg(struct imsgbuf *ibuf, int idx, struct mrt_head *mrt_l)
385{
386	struct imsg		 imsg;
387	int			 n;
388
389	if ((n = imsg_read(ibuf)) == -1)
390		return (-1);
391
392	if (n == 0) {	/* connection closed */
393		logit(LOG_CRIT, "dispatch_imsg in main: pipe closed");
394		return (-1);
395	}
396
397	for (;;) {
398		if ((n = imsg_get(ibuf, &imsg)) == -1)
399			return (-1);
400
401		if (n == 0)
402			break;
403
404		switch (imsg.hdr.type) {
405		case IMSG_MRT_MSG:
406		case IMSG_MRT_END:
407			if (mrt_queue(mrt_l, &imsg) == -1)
408				logit(LOG_CRIT, "mrt_queue failed.");
409			break;
410		case IMSG_KROUTE_CHANGE:
411			if (idx != PFD_PIPE_ROUTE)
412				logit(LOG_CRIT, "route request not from RDE");
413			else if (kr_change(imsg.data))
414				return (-1);
415			break;
416		case IMSG_KROUTE_DELETE:
417			if (idx != PFD_PIPE_ROUTE)
418				logit(LOG_CRIT, "route request not from RDE");
419			else if (kr_delete(imsg.data))
420				return (-1);
421			break;
422		case IMSG_NEXTHOP_ADD:
423			if (idx != PFD_PIPE_ROUTE)
424				logit(LOG_CRIT, "nexthop request not from RDE");
425			else
426				if (imsg.hdr.len != IMSG_HEADER_SIZE +
427				    sizeof(struct bgpd_addr))
428					logit(LOG_CRIT, "wrong imsg len");
429				else if (kr_nexthop_add(imsg.data) == -1)
430					return (-1);
431			break;
432		case IMSG_NEXTHOP_REMOVE:
433			if (idx != PFD_PIPE_ROUTE)
434				logit(LOG_CRIT, "nexthop request not from RDE");
435			else
436				if (imsg.hdr.len != IMSG_HEADER_SIZE +
437				    sizeof(struct bgpd_addr))
438					logit(LOG_CRIT, "wrong imsg len");
439				else kr_nexthop_delete(imsg.data);
440			break;
441		case IMSG_CTL_RELOAD:
442			if (idx != PFD_PIPE_SESSION)
443				logit(LOG_CRIT, "reload request not from SE");
444			else
445				reconfig = 1;
446			break;
447		case IMSG_CTL_FIB_COUPLE:
448			if (idx != PFD_PIPE_SESSION)
449				logit(LOG_CRIT, "couple request not from SE");
450			else
451				kr_fib_couple();
452			break;
453		case IMSG_CTL_FIB_DECOUPLE:
454			if (idx != PFD_PIPE_SESSION)
455				logit(LOG_CRIT, "decouple request not from SE");
456			else
457				kr_fib_decouple();
458			break;
459		case IMSG_CTL_KROUTE:
460		case IMSG_CTL_KROUTE_ADDR:
461		case IMSG_CTL_SHOW_NEXTHOP:
462		case IMSG_CTL_SHOW_INTERFACE:
463			if (idx != PFD_PIPE_SESSION)
464				logit(LOG_CRIT, "kroute request not from SE");
465			else
466				kr_show_route(&imsg);
467			break;
468		default:
469			break;
470		}
471		imsg_free(&imsg);
472	}
473	return (0);
474}
475
476void
477send_nexthop_update(struct kroute_nexthop *msg)
478{
479	char	*gw = NULL, *nh = NULL;
480
481	if (msg->gateway.af == AF_INET)
482		if (asprintf(&gw, ": via %s",
483		    log_ntoa(msg->gateway.v4.s_addr)) == -1) {
484			log_err("send_nexthop_update");
485			quit = 1;
486		}
487
488	if (msg->nexthop.af == AF_INET)
489		nh = log_ntoa(msg->nexthop.v4.s_addr);
490
491	logit(LOG_INFO, "nexthop %s now %s%s%s", nh,
492	    msg->valid ? "valid" : "invalid",
493	    msg->connected ? ": directly connected" : "",
494	    msg->gateway.af ? gw : "");
495
496	free(gw);
497
498	if (imsg_compose(&ibuf_rde, IMSG_NEXTHOP_UPDATE, 0,
499	    msg, sizeof(struct kroute_nexthop)) == -1)
500		quit = 1;
501}
502
503void
504send_imsg_session(int type, pid_t pid, void *data, u_int16_t datalen)
505{
506	imsg_compose_pid(&ibuf_se, type, pid, data, datalen);
507}
508
509
510