bgpd.c revision 1.69 
1/*	$OpenBSD: bgpd.c,v 1.69 2004/01/20 09:44:33 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 <pwd.h>
29#include <signal.h>
30#include <stdio.h>
31#include <stdlib.h>
32#include <string.h>
33#include <unistd.h>
34
35#include "mrt.h"
36#include "bgpd.h"
37#include "session.h"
38
39void	sighdlr(int);
40void	usage(void);
41int	main(int, char *[]);
42int	check_child(pid_t, const char *);
43int	reconfigure(char *, struct bgpd_config *, struct mrt_head *,
44	    struct peer *);
45int	dispatch_imsg(struct imsgbuf *, int, struct mrt_head *);
46
47int			rfd = -1;
48volatile sig_atomic_t	mrtdump = 0;
49volatile sig_atomic_t	quit = 0;
50volatile sig_atomic_t	reconfig = 0;
51volatile sig_atomic_t	sigchld = 0;
52struct imsgbuf		ibuf_se;
53struct imsgbuf		ibuf_rde;
54
55void
56sighdlr(int sig)
57{
58	switch (sig) {
59	case SIGTERM:
60	case SIGINT:
61		quit = 1;
62		break;
63	case SIGCHLD:
64		sigchld = 1;
65		break;
66	case SIGHUP:
67		reconfig = 1;
68		break;
69	case SIGALRM:
70	case SIGUSR1:
71		mrtdump = 1;
72		break;
73	}
74}
75
76void
77usage(void)
78{
79	extern char *__progname;
80
81	fprintf(stderr, "usage: %s [-dnv] ", __progname);
82	fprintf(stderr, "[-D macro=value] [-f file]\n");
83	exit(1);
84}
85
86#define POLL_MAX		8
87#define PFD_PIPE_SESSION	0
88#define PFD_PIPE_ROUTE		1
89#define PFD_SOCK_ROUTE		2
90#define PFD_MRT_START		3
91
92int
93main(int argc, char *argv[])
94{
95	struct bgpd_config	 conf;
96	struct peer		*peer_l, *p, *next;
97	struct mrt_head		 mrt_l;
98	struct network_head	 net_l;
99	struct network		*net;
100	struct mrt		*(mrt[POLL_MAX]);
101	struct pollfd		 pfd[POLL_MAX];
102	pid_t			 io_pid = 0, rde_pid = 0, pid;
103	char			*conffile;
104	int			 debug = 0;
105	int			 ch, csock, i, j, n, nfds, timeout;
106	int			 pipe_m2s[2];
107	int			 pipe_m2r[2];
108	int			 pipe_s2r[2];
109
110	conffile = CONFFILE;
111	bgpd_process = PROC_MAIN;
112
113	log_init(1);		/* log to stderr until daemonized */
114
115	bzero(&conf, sizeof(conf));
116	LIST_INIT(&mrt_l);
117	TAILQ_INIT(&net_l);
118	peer_l = NULL;
119
120	while ((ch = getopt(argc, argv, "dD:f:nv")) != -1) {
121		switch (ch) {
122		case 'd':
123			debug = 1;
124			break;
125		case 'D':
126			if (cmdline_symset(optarg) < 0)
127				logit(LOG_CRIT,
128				    "could not parse macro definition %s",
129				    optarg);
130			break;
131		case 'f':
132			conffile = optarg;
133			break;
134		case 'n':
135			conf.opts |= BGPD_OPT_NOACTION;
136			break;
137		case 'v':
138			if (conf.opts & BGPD_OPT_VERBOSE)
139				conf.opts |= BGPD_OPT_VERBOSE2;
140			conf.opts |= BGPD_OPT_VERBOSE;
141			break;
142		default:
143			usage();
144			/* NOTREACHED */
145		}
146	}
147
148	if (parse_config(conffile, &conf, &mrt_l, &peer_l, &net_l))
149		exit(1);
150
151	if (conf.opts & BGPD_OPT_NOACTION) {
152		fprintf(stderr, "configuration OK\n");
153		exit(0);
154	}
155
156	if (geteuid())
157		errx(1, "need root privileges");
158
159	if (getpwnam(BGPD_USER) == NULL)
160		errx(1, "unknown user %s", BGPD_USER);
161	endpwent();
162
163	log_init(debug);
164
165	if (!debug)
166		daemon(1, 0);
167
168	logit(LOG_INFO, "startup");
169
170	if (pipe(pipe_m2s) == -1)
171		fatal("pipe");
172	if (fcntl(pipe_m2s[0], F_SETFL, O_NONBLOCK) == -1 ||
173	    fcntl(pipe_m2s[1], F_SETFL, O_NONBLOCK) == -1)
174		fatal("fcntl");
175	if (pipe(pipe_m2r) == -1)
176		fatal("pipe");
177	if (fcntl(pipe_m2r[0], F_SETFL, O_NONBLOCK) == -1 ||
178	    fcntl(pipe_m2r[1], F_SETFL, O_NONBLOCK) == -1)
179		fatal("fcntl");
180	if (pipe(pipe_s2r) == -1)
181		fatal("pipe");
182	if (fcntl(pipe_s2r[0], F_SETFL, O_NONBLOCK) == -1 ||
183	    fcntl(pipe_s2r[1], F_SETFL, O_NONBLOCK) == -1)
184		fatal("fcntl");
185
186	if ((csock = control_init()) == -1)
187		fatalx("control socket setup failed");
188
189	/* fork children */
190	rde_pid = rde_main(&conf, peer_l, &net_l, pipe_m2r, pipe_s2r);
191	io_pid = session_main(&conf, peer_l, pipe_m2s, pipe_s2r);
192
193	setproctitle("parent");
194
195	signal(SIGTERM, sighdlr);
196	signal(SIGINT, sighdlr);
197	signal(SIGCHLD, sighdlr);
198	signal(SIGHUP, sighdlr);
199	signal(SIGALRM, sighdlr);
200	signal(SIGUSR1, sighdlr);
201
202	close(pipe_m2s[1]);
203	close(pipe_m2r[1]);
204	close(pipe_s2r[0]);
205	close(pipe_s2r[1]);
206	close(csock);
207
208	imsg_init(&ibuf_se, pipe_m2s[0]);
209	imsg_init(&ibuf_rde, pipe_m2r[0]);
210	mrt_init(&ibuf_rde, &ibuf_se);
211	if ((rfd = kr_init(!(conf.flags & BGPD_FLAG_NO_FIB_UPDATE))) == -1)
212		quit = 1;
213
214	for (p = peer_l; p != NULL; p = next) {
215		next = p->next;
216		free(p);
217	}
218	for (net = TAILQ_FIRST(&net_l); net != TAILQ_END(&net_l);
219	    net = TAILQ_FIRST(&net_l)) {
220		TAILQ_REMOVE(&net_l, net, network_l);
221		free(net);
222	}
223
224	while (quit == 0) {
225		pfd[PFD_PIPE_SESSION].fd = ibuf_se.sock;
226		pfd[PFD_PIPE_SESSION].events = POLLIN;
227		if (ibuf_se.w.queued)
228			pfd[PFD_PIPE_SESSION].events |= POLLOUT;
229		pfd[PFD_PIPE_ROUTE].fd = ibuf_rde.sock;
230		pfd[PFD_PIPE_ROUTE].events = POLLIN;
231		if (ibuf_rde.w.queued)
232			pfd[PFD_PIPE_ROUTE].events |= POLLOUT;
233		pfd[PFD_SOCK_ROUTE].fd = rfd;
234		pfd[PFD_SOCK_ROUTE].events = POLLIN;
235		i = PFD_MRT_START;
236		i = mrt_select(&mrt_l, pfd, mrt, i, POLL_MAX, &timeout);
237
238		if ((nfds = poll(pfd, i, INFTIM)) == -1)
239			if (errno != EINTR) {
240				log_err("poll error");
241				quit = 1;
242			}
243
244		if (nfds > 0 && (pfd[PFD_PIPE_SESSION].revents & POLLOUT))
245			if ((n = msgbuf_write(&ibuf_se.w)) < 0) {
246				log_err("pipe write error (to SE)");
247				quit = 1;
248			}
249
250		if (nfds > 0 && (pfd[PFD_PIPE_ROUTE].revents & POLLOUT))
251			if ((n = msgbuf_write(&ibuf_rde.w)) < 0) {
252				log_err("pipe write error (to RDE)");
253				quit = 1;
254			}
255
256		if (nfds > 0 && pfd[PFD_PIPE_SESSION].revents & POLLIN) {
257			nfds--;
258			if (dispatch_imsg(&ibuf_se, PFD_PIPE_SESSION,
259			    &mrt_l) == -1)
260				quit = 1;
261		}
262
263		if (nfds > 0 && pfd[PFD_PIPE_ROUTE].revents & POLLIN) {
264			nfds--;
265			if (dispatch_imsg(&ibuf_rde, PFD_PIPE_ROUTE,
266			    &mrt_l) == -1)
267				quit = 1;
268		}
269
270		if (nfds > 0 && pfd[PFD_SOCK_ROUTE].revents & POLLIN) {
271			nfds--;
272			if (kr_dispatch_msg() == -1)
273				quit = 1;
274		}
275
276		for (j = PFD_MRT_START; j < i && nfds > 0 ; j++) {
277			if (pfd[j].revents & POLLOUT) {
278				if ((n = mrt_write(mrt[j])) < 0) {
279					log_err("mrt write error");
280				}
281			}
282		}
283
284		if (reconfig) {
285			logit(LOG_CRIT, "rereading config");
286			reconfigure(conffile, &conf, &mrt_l, peer_l);
287			reconfig = 0;
288		}
289
290		if (sigchld) {
291			if (check_child(io_pid, "session engine"))
292				quit = 1;
293			if (check_child(rde_pid, "route decision engine"))
294				quit = 1;
295			sigchld = 0;
296		}
297
298		if (mrtdump == 1) {
299			mrt_handler(&mrt_l);
300			mrtdump = 0;
301		}
302	}
303
304	signal(SIGCHLD, SIG_IGN);
305
306	if (io_pid)
307		kill(io_pid, SIGTERM);
308
309	if (rde_pid)
310		kill(rde_pid, SIGTERM);
311
312	do {
313		pid = waitpid(-1, NULL, WNOHANG);
314	} while (pid > 0 || (pid == -1 && errno == EINTR));
315
316	control_cleanup();
317	kr_shutdown();
318
319	logit(LOG_CRIT, "Terminating");
320	return (0);
321}
322
323int
324check_child(pid_t pid, const char *pname)
325{
326	int	status;
327
328	if (waitpid(pid, &status, WNOHANG) > 0) {
329		if (WIFEXITED(status)) {
330			logit(LOG_CRIT, "Lost child: %s exited", pname);
331			return (1);
332		}
333		if (WIFSIGNALED(status)) {
334			logit(LOG_CRIT, "Lost child: %s terminated; signal %d",
335			    pname, WTERMSIG(status));
336			return (1);
337		}
338	}
339
340	return (0);
341}
342
343int
344reconfigure(char *conffile, struct bgpd_config *conf, struct mrt_head *mrt_l,
345    struct peer *peer_l)
346{
347	struct network_head	 net_l;
348	struct network		*n;
349	struct peer		*p, *next;
350
351	if (parse_config(conffile, conf, mrt_l, &peer_l, &net_l)) {
352		logit(LOG_CRIT, "config file %s has errors, not reloading",
353		    conffile);
354		return (-1);
355	}
356
357	if (imsg_compose(&ibuf_se, IMSG_RECONF_CONF, 0,
358	    conf, sizeof(struct bgpd_config)) == -1)
359		return (-1);
360	if (imsg_compose(&ibuf_rde, IMSG_RECONF_CONF, 0,
361	    conf, sizeof(struct bgpd_config)) == -1)
362		return (-1);
363	for (p = peer_l; p != NULL; p = next) {
364		next = p->next;
365		if (imsg_compose(&ibuf_se, IMSG_RECONF_PEER, p->conf.id,
366		    &p->conf, sizeof(struct peer_config)) == -1)
367			return (-1);
368		if (imsg_compose(&ibuf_rde, IMSG_RECONF_PEER, p->conf.id,
369		    &p->conf, sizeof(struct peer_config)) == -1)
370			return (-1);
371		free(p);
372	}
373	for (n = TAILQ_FIRST(&net_l); n != TAILQ_END(&net_l);
374	    n = TAILQ_FIRST(&net_l)) {
375		if (imsg_compose(&ibuf_rde, IMSG_RECONF_NETWORK, 0,
376		    &n->net, sizeof(struct network_config)) == -1)
377			return (-1);
378		TAILQ_REMOVE(&net_l, n, network_l);
379		free(n);
380	}
381	if (imsg_compose(&ibuf_se, IMSG_RECONF_DONE, 0, NULL, 0) == -1 ||
382	    imsg_compose(&ibuf_rde, IMSG_RECONF_DONE, 0, NULL, 0) == -1)
383		return (-1);
384
385	return (0);
386}
387
388int
389dispatch_imsg(struct imsgbuf *ibuf, int idx, struct mrt_head *mrt_l)
390{
391	struct imsg		 imsg;
392	int			 n;
393
394	if ((n = imsg_read(ibuf)) == -1)
395		return (-1);
396
397	if (n == 0) {	/* connection closed */
398		logit(LOG_CRIT, "dispatch_imsg in main: pipe closed");
399		return (-1);
400	}
401
402	for (;;) {
403		if ((n = imsg_get(ibuf, &imsg)) == -1)
404			return (-1);
405
406		if (n == 0)
407			break;
408
409		switch (imsg.hdr.type) {
410		case IMSG_MRT_MSG:
411		case IMSG_MRT_END:
412			if (mrt_queue(mrt_l, &imsg) == -1)
413				logit(LOG_CRIT, "mrt_queue failed.");
414			break;
415		case IMSG_KROUTE_CHANGE:
416			if (idx != PFD_PIPE_ROUTE)
417				logit(LOG_CRIT, "route request not from RDE");
418			else if (kr_change(imsg.data))
419				return (-1);
420			break;
421		case IMSG_KROUTE_DELETE:
422			if (idx != PFD_PIPE_ROUTE)
423				logit(LOG_CRIT, "route request not from RDE");
424			else if (kr_delete(imsg.data))
425				return (-1);
426			break;
427		case IMSG_NEXTHOP_ADD:
428			if (idx != PFD_PIPE_ROUTE)
429				logit(LOG_CRIT, "nexthop request not from RDE");
430			else
431				if (imsg.hdr.len != IMSG_HEADER_SIZE +
432				    sizeof(struct bgpd_addr))
433					logit(LOG_CRIT, "wrong imsg len");
434				else if (kr_nexthop_add(imsg.data) == -1)
435					return (-1);
436			break;
437		case IMSG_NEXTHOP_REMOVE:
438			if (idx != PFD_PIPE_ROUTE)
439				logit(LOG_CRIT, "nexthop request not from RDE");
440			else
441				if (imsg.hdr.len != IMSG_HEADER_SIZE +
442				    sizeof(struct bgpd_addr))
443					logit(LOG_CRIT, "wrong imsg len");
444				else kr_nexthop_delete(imsg.data);
445			break;
446		case IMSG_CTL_RELOAD:
447			if (idx != PFD_PIPE_SESSION)
448				logit(LOG_CRIT, "reload request not from SE");
449			else
450				reconfig = 1;
451			break;
452		case IMSG_CTL_FIB_COUPLE:
453			if (idx != PFD_PIPE_SESSION)
454				logit(LOG_CRIT, "couple request not from SE");
455			else
456				kr_fib_couple();
457			break;
458		case IMSG_CTL_FIB_DECOUPLE:
459			if (idx != PFD_PIPE_SESSION)
460				logit(LOG_CRIT, "decouple request not from SE");
461			else
462				kr_fib_decouple();
463			break;
464		case IMSG_CTL_KROUTE:
465		case IMSG_CTL_KROUTE_ADDR:
466		case IMSG_CTL_SHOW_NEXTHOP:
467		case IMSG_CTL_SHOW_INTERFACE:
468			if (idx != PFD_PIPE_SESSION)
469				logit(LOG_CRIT, "kroute request not from SE");
470			else
471				kr_show_route(&imsg);
472			break;
473		default:
474			break;
475		}
476		imsg_free(&imsg);
477	}
478	return (0);
479}
480
481void
482send_nexthop_update(struct kroute_nexthop *msg)
483{
484	char	*gw = NULL, *nh = NULL;
485
486	if (msg->gateway.af == AF_INET)
487		if (asprintf(&gw, ": via %s",
488		    log_ntoa(msg->gateway.v4.s_addr)) == -1) {
489			log_err("send_nexthop_update");
490			quit = 1;
491		}
492
493	if (msg->nexthop.af == AF_INET)
494		nh = log_ntoa(msg->nexthop.v4.s_addr);
495
496	logit(LOG_INFO, "nexthop %s now %s%s%s", nh,
497	    msg->valid ? "valid" : "invalid",
498	    msg->connected ? ": directly connected" : "",
499	    msg->gateway.af ? gw : "");
500
501	free(gw);
502
503	if (imsg_compose(&ibuf_rde, IMSG_NEXTHOP_UPDATE, 0,
504	    msg, sizeof(struct kroute_nexthop)) == -1)
505		quit = 1;
506}
507
508void
509send_imsg_session(int type, pid_t pid, void *data, u_int16_t datalen)
510{
511	imsg_compose_pid(&ibuf_se, type, pid, data, datalen);
512}
513
514
515