bgpd.c revision 1.61 
1/*	$OpenBSD: bgpd.c,v 1.61 2004/01/09 19:08:50 henning 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		 mrtconf;
97	struct mrt		*(mrt[POLL_MAX]);
98	struct pollfd		 pfd[POLL_MAX];
99	pid_t			 io_pid = 0, rde_pid = 0, pid;
100	char			*conffile;
101	int			 debug = 0;
102	int			 ch, csock, i, j, n, nfds, timeout;
103	int			 pipe_m2s[2];
104	int			 pipe_m2r[2];
105	int			 pipe_s2r[2];
106
107	conffile = CONFFILE;
108	bgpd_process = PROC_MAIN;
109
110	log_init(1);		/* log to stderr until daemonized */
111
112	bzero(&conf, sizeof(conf));
113	LIST_INIT(&mrtconf);
114	peer_l = NULL;
115
116	while ((ch = getopt(argc, argv, "dD:f:nv")) != -1) {
117		switch (ch) {
118		case 'd':
119			debug = 1;
120			break;
121		case 'D':
122			if (cmdline_symset(optarg) < 0)
123				logit(LOG_CRIT,
124				    "could not parse macro definition %s",
125				    optarg);
126			break;
127		case 'f':
128			conffile = optarg;
129			break;
130		case 'n':
131			conf.opts |= BGPD_OPT_NOACTION;
132			break;
133		case 'v':
134			if (conf.opts & BGPD_OPT_VERBOSE)
135				conf.opts |= BGPD_OPT_VERBOSE2;
136			conf.opts |= BGPD_OPT_VERBOSE;
137			break;
138		default:
139			usage();
140			/* NOTREACHED */
141		}
142	}
143
144	if (parse_config(conffile, &conf, &mrtconf, &peer_l))
145		exit(1);
146
147	if (conf.opts & BGPD_OPT_NOACTION) {
148		fprintf(stderr, "configuration OK\n");
149		exit(0);
150	}
151
152	if (geteuid())
153		errx(1, "need root privileges");
154
155	log_init(debug);
156
157	if (!debug)
158		daemon(1, 0);
159
160	logit(LOG_INFO, "startup");
161
162	if (pipe(pipe_m2s) == -1)
163		fatal("pipe");
164	if (fcntl(pipe_m2s[0], F_SETFL, O_NONBLOCK) == -1 ||
165	    fcntl(pipe_m2s[1], F_SETFL, O_NONBLOCK) == -1)
166		fatal("fcntl");
167	if (pipe(pipe_m2r) == -1)
168		fatal("pipe");
169	if (fcntl(pipe_m2r[0], F_SETFL, O_NONBLOCK) == -1 ||
170	    fcntl(pipe_m2r[1], F_SETFL, O_NONBLOCK) == -1)
171		fatal("fcntl");
172	if (pipe(pipe_s2r) == -1)
173		fatal("pipe");
174	if (fcntl(pipe_s2r[0], F_SETFL, O_NONBLOCK) == -1 ||
175	    fcntl(pipe_s2r[1], F_SETFL, O_NONBLOCK) == -1)
176		fatal("fcntl");
177
178	if ((csock = control_init()) == -1)
179		fatalx("control socket setup failed");
180
181	/* fork children */
182	rde_pid = rde_main(&conf, peer_l, pipe_m2r, pipe_s2r);
183	io_pid = session_main(&conf, peer_l, pipe_m2s, pipe_s2r);
184
185	setproctitle("parent");
186
187	signal(SIGTERM, sighdlr);
188	signal(SIGINT, sighdlr);
189	signal(SIGCHLD, sighdlr);
190	signal(SIGHUP, sighdlr);
191	signal(SIGALRM, sighdlr);
192	signal(SIGUSR1, sighdlr);
193
194	close(pipe_m2s[1]);
195	close(pipe_m2r[1]);
196	close(pipe_s2r[0]);
197	close(pipe_s2r[1]);
198	close(csock);
199
200	imsg_init(&ibuf_se, pipe_m2s[0]);
201	imsg_init(&ibuf_rde, pipe_m2r[0]);
202	mrt_init(&ibuf_rde, &ibuf_se);
203	if ((rfd = kr_init(!(conf.flags & BGPD_FLAG_NO_FIB_UPDATE))) == -1)
204		quit = 1;
205
206	for (p = peer_l; p != NULL; p = next) {
207		next = p->next;
208		free(p);
209	}
210
211	while (quit == 0) {
212		pfd[PFD_PIPE_SESSION].fd = ibuf_se.sock;
213		pfd[PFD_PIPE_SESSION].events = POLLIN;
214		if (ibuf_se.w.queued)
215			pfd[PFD_PIPE_SESSION].events |= POLLOUT;
216		pfd[PFD_PIPE_ROUTE].fd = ibuf_rde.sock;
217		pfd[PFD_PIPE_ROUTE].events = POLLIN;
218		if (ibuf_rde.w.queued)
219			pfd[PFD_PIPE_ROUTE].events |= POLLOUT;
220		pfd[PFD_SOCK_ROUTE].fd = rfd;
221		pfd[PFD_SOCK_ROUTE].events = POLLIN;
222		i = PFD_MRT_START;
223		i = mrt_select(&mrtconf, pfd, mrt, i, POLL_MAX, &timeout);
224
225		if ((nfds = poll(pfd, i, INFTIM)) == -1)
226			if (errno != EINTR) {
227				log_err("poll error");
228				quit = 1;
229			}
230
231		if (nfds > 0 && (pfd[PFD_PIPE_SESSION].revents & POLLOUT))
232			if ((n = msgbuf_write(&ibuf_se.w)) < 0) {
233				log_err("pipe write error (to SE)");
234				quit = 1;
235			}
236
237		if (nfds > 0 && (pfd[PFD_PIPE_ROUTE].revents & POLLOUT))
238			if ((n = msgbuf_write(&ibuf_rde.w)) < 0) {
239				log_err("pipe write error (to RDE)");
240				quit = 1;
241			}
242
243		if (nfds > 0 && pfd[PFD_PIPE_SESSION].revents & POLLIN) {
244			nfds--;
245			if (dispatch_imsg(&ibuf_se, PFD_PIPE_SESSION,
246			    &mrtconf) == -1)
247				quit = 1;
248		}
249
250		if (nfds > 0 && pfd[PFD_PIPE_ROUTE].revents & POLLIN) {
251			nfds--;
252			if (dispatch_imsg(&ibuf_rde, PFD_PIPE_ROUTE,
253			    &mrtconf) == -1)
254				quit = 1;
255		}
256
257		if (nfds > 0 && pfd[PFD_SOCK_ROUTE].revents & POLLIN) {
258			nfds--;
259			if (kr_dispatch_msg() == -1)
260				quit = 1;
261		}
262
263		for (j = PFD_MRT_START; j < i && nfds > 0 ; j++) {
264			if (pfd[j].revents & POLLOUT) {
265				if ((n = mrt_write(mrt[i])) < 0) {
266					log_err("mrt write error");
267				}
268			}
269		}
270
271		if (reconfig) {
272			logit(LOG_CRIT, "rereading config");
273			reconfigure(conffile, &conf, &mrtconf, peer_l);
274			reconfig = 0;
275		}
276
277		if (sigchld) {
278			if (check_child(io_pid, "session engine"))
279				quit = 1;
280			if (check_child(rde_pid, "route decision engine"))
281				quit = 1;
282			sigchld = 0;
283		}
284
285		if (mrtdump == 1) {
286			mrt_handler(&mrtconf);
287			mrtdump = 0;
288		}
289	}
290
291	signal(SIGCHLD, SIG_IGN);
292
293	if (io_pid)
294		kill(io_pid, SIGTERM);
295
296	if (rde_pid)
297		kill(rde_pid, SIGTERM);
298
299	do {
300		pid = waitpid(-1, NULL, WNOHANG);
301	} while (pid > 0 || (pid == -1 && errno == EINTR));
302
303	control_cleanup();
304	kr_shutdown();
305
306	logit(LOG_CRIT, "Terminating");
307	return (0);
308}
309
310int
311check_child(pid_t pid, const char *pname)
312{
313	int	status;
314
315	if (waitpid(pid, &status, WNOHANG) > 0) {
316		if (WIFEXITED(status)) {
317			logit(LOG_CRIT, "Lost child: %s exited", pname);
318			return (1);
319		}
320		if (WIFSIGNALED(status)) {
321			logit(LOG_CRIT, "Lost child: %s terminated; signal %d",
322			    pname, WTERMSIG(status));
323			return (1);
324		}
325	}
326
327	return (0);
328}
329
330int
331reconfigure(char *conffile, struct bgpd_config *conf, struct mrt_head *mrtc,
332    struct peer *peer_l)
333{
334	struct peer		*p, *next;
335
336	if (parse_config(conffile, conf, mrtc, &peer_l)) {
337		logit(LOG_CRIT, "config file %s has errors, not reloading",
338		    conffile);
339		return (-1);
340	}
341
342	if (imsg_compose(&ibuf_se, IMSG_RECONF_CONF, 0,
343	    conf, sizeof(struct bgpd_config)) == -1)
344		return (-1);
345	if (imsg_compose(&ibuf_rde, IMSG_RECONF_CONF, 0,
346	    conf, sizeof(struct bgpd_config)) == -1)
347		return (-1);
348	for (p = peer_l; p != NULL; p = next) {
349		next = p->next;
350		if (imsg_compose(&ibuf_se, IMSG_RECONF_PEER, p->conf.id,
351		    &p->conf, sizeof(struct peer_config)) == -1)
352			return (-1);
353		if (imsg_compose(&ibuf_rde, IMSG_RECONF_PEER, p->conf.id,
354		    &p->conf, sizeof(struct peer_config)) == -1)
355			return (-1);
356		free(p);
357	}
358	if (imsg_compose(&ibuf_se, IMSG_RECONF_DONE, 0, NULL, 0) == -1 ||
359	    imsg_compose(&ibuf_rde, IMSG_RECONF_DONE, 0, NULL, 0) == -1)
360		return (-1);
361
362	return (0);
363}
364
365int
366dispatch_imsg(struct imsgbuf *ibuf, int idx, struct mrt_head *mrtc)
367{
368	struct imsg	 imsg;
369	int		 n;
370	in_addr_t	 ina;
371
372	if ((n = imsg_read(ibuf)) == -1)
373		return (-1);
374
375	if (n == 0) {	/* connection closed */
376		logit(LOG_CRIT, "dispatch_imsg in main: pipe closed");
377		return (-1);
378	}
379
380	for (;;) {
381		if ((n = imsg_get(ibuf, &imsg)) == -1)
382			return (-1);
383
384		if (n == 0)
385			break;
386
387		switch (imsg.hdr.type) {
388		case IMSG_MRT_MSG:
389		case IMSG_MRT_END:
390			if (mrt_queue(mrtc, &imsg) == -1)
391				logit(LOG_CRIT, "mrt_queue failed.");
392			break;
393		case IMSG_KROUTE_CHANGE:
394			if (idx != PFD_PIPE_ROUTE)
395				logit(LOG_CRIT, "route request not from RDE");
396			else if (kr_change(imsg.data))
397				return (-1);
398			break;
399		case IMSG_KROUTE_DELETE:
400			if (idx != PFD_PIPE_ROUTE)
401				logit(LOG_CRIT, "route request not from RDE");
402			else if (kr_delete(imsg.data))
403				return (-1);
404			break;
405		case IMSG_NEXTHOP_ADD:
406			if (idx != PFD_PIPE_ROUTE)
407				logit(LOG_CRIT, "nexthop request not from RDE");
408			else {
409				memcpy(&ina, imsg.data, sizeof(ina));
410				if (kr_nexthop_add(ina) == -1)
411					return (-1);
412			}
413			break;
414		case IMSG_NEXTHOP_REMOVE:
415			if (idx != PFD_PIPE_ROUTE)
416				logit(LOG_CRIT, "nexthop request not from RDE");
417			else {
418				memcpy(&ina, imsg.data, sizeof(ina));
419				kr_nexthop_delete(ina);
420			}
421			break;
422		case IMSG_CTL_RELOAD:
423			if (idx != PFD_PIPE_SESSION)
424				logit(LOG_CRIT, "reload request not from SE");
425			else
426				reconfig = 1;
427			break;
428		case IMSG_CTL_FIB_COUPLE:
429			if (idx != PFD_PIPE_SESSION)
430				logit(LOG_CRIT, "couple request not from SE");
431			else
432				kr_fib_couple();
433			break;
434		case IMSG_CTL_FIB_DECOUPLE:
435			if (idx != PFD_PIPE_SESSION)
436				logit(LOG_CRIT, "decouple request not from SE");
437			else
438				kr_fib_decouple();
439			break;
440		case IMSG_CTL_KROUTE:
441		case IMSG_CTL_KROUTE_ADDR:
442			if (idx != PFD_PIPE_SESSION)
443				logit(LOG_CRIT, "kroute request not from SE");
444			else
445				kr_show_route(&imsg);
446			break;
447		default:
448			break;
449		}
450		imsg_free(&imsg);
451	}
452	return (0);
453}
454
455void
456send_nexthop_update(struct kroute_nexthop *msg)
457{
458	char	*gw = NULL;
459
460	if (msg->gateway)
461		if (asprintf(&gw, ": via %s", log_ntoa(msg->gateway)) == -1) {
462			log_err("send_nexthop_update");
463			quit = 1;
464		}
465
466	logit(LOG_INFO, "nexthop %s now %s%s%s", log_ntoa(msg->nexthop),
467	    msg->valid ? "valid" : "invalid",
468	    msg->connected ? ": directly connected" : "",
469	    msg->gateway ? gw : "");
470
471	free(gw);
472
473	if (imsg_compose(&ibuf_rde, IMSG_NEXTHOP_UPDATE, 0,
474	    msg, sizeof(struct kroute_nexthop)) == -1)
475		quit = 1;
476}
477
478void
479send_imsg_session(int type, pid_t pid, void *data, u_int16_t datalen)
480{
481	imsg_compose_pid(&ibuf_se, type, pid, data, datalen);
482}
483
484
485