xref: /openbsd-src/usr.sbin/ospfd/control.c (revision 4c1e55dc91edd6e69ccc60ce855900fbc12cf34f)
1 /*	$OpenBSD: control.c,v 1.37 2012/04/11 08:33:53 deraadt 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/stat.h>
21 #include <sys/socket.h>
22 #include <sys/un.h>
23 #include <errno.h>
24 #include <fcntl.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <unistd.h>
28 
29 #include "ospfd.h"
30 #include "ospf.h"
31 #include "ospfe.h"
32 #include "log.h"
33 #include "control.h"
34 
35 #define	CONTROL_BACKLOG	5
36 
37 struct ctl_conn	*control_connbyfd(int);
38 struct ctl_conn	*control_connbypid(pid_t);
39 void		 control_close(int);
40 
41 int
42 control_init(char *path)
43 {
44 	struct sockaddr_un	 sun;
45 	int			 fd;
46 	mode_t			 old_umask;
47 
48 	if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
49 		log_warn("control_init: socket");
50 		return (-1);
51 	}
52 
53 	bzero(&sun, sizeof(sun));
54 	sun.sun_family = AF_UNIX;
55 	strlcpy(sun.sun_path, path, sizeof(sun.sun_path));
56 
57 	if (unlink(path) == -1)
58 		if (errno != ENOENT) {
59 			log_warn("control_init: unlink %s", path);
60 			close(fd);
61 			return (-1);
62 		}
63 
64 	old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
65 	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
66 		log_warn("control_init: bind: %s", path);
67 		close(fd);
68 		umask(old_umask);
69 		return (-1);
70 	}
71 	umask(old_umask);
72 
73 	if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {
74 		log_warn("control_init: chmod");
75 		close(fd);
76 		(void)unlink(path);
77 		return (-1);
78 	}
79 
80 	session_socket_blockmode(fd, BM_NONBLOCK);
81 	control_state.fd = fd;
82 
83 	return (0);
84 }
85 
86 int
87 control_listen(void)
88 {
89 
90 	if (listen(control_state.fd, CONTROL_BACKLOG) == -1) {
91 		log_warn("control_listen: listen");
92 		return (-1);
93 	}
94 
95 	event_set(&control_state.ev, control_state.fd, EV_READ,
96 	    control_accept, NULL);
97 	event_add(&control_state.ev, NULL);
98 	evtimer_set(&control_state.evt, control_accept, NULL);
99 
100 	return (0);
101 }
102 
103 void
104 control_cleanup(char *path)
105 {
106 	if (path == NULL)
107 		return;
108 	event_del(&control_state.ev);
109 	event_del(&control_state.evt);
110 	unlink(path);
111 }
112 
113 /* ARGSUSED */
114 void
115 control_accept(int listenfd, short event, void *bula)
116 {
117 	int			 connfd;
118 	socklen_t		 len;
119 	struct sockaddr_un	 sun;
120 	struct ctl_conn		*c;
121 
122 	event_add(&control_state.ev, NULL);
123 	if ((event & EV_TIMEOUT))
124 		return;
125 
126 	len = sizeof(sun);
127 	if ((connfd = accept(listenfd,
128 	    (struct sockaddr *)&sun, &len)) == -1) {
129 		/*
130 		 * Pause accept if we are out of file descriptors, or
131 		 * libevent will haunt us here too.
132 		 */
133 		if (errno == ENFILE || errno == EMFILE) {
134 			struct timeval evtpause = { 1, 0 };
135 
136 			event_del(&control_state.ev);
137 			evtimer_add(&control_state.evt, &evtpause);
138 		} else if (errno != EWOULDBLOCK && errno != EINTR)
139 			log_warn("control_accept: accept");
140 		return;
141 	}
142 
143 	session_socket_blockmode(connfd, BM_NONBLOCK);
144 
145 	if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {
146 		log_warn("control_accept");
147 		close(connfd);
148 		return;
149 	}
150 
151 	imsg_init(&c->iev.ibuf, connfd);
152 	c->iev.handler = control_dispatch_imsg;
153 	c->iev.events = EV_READ;
154 	event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events,
155 	    c->iev.handler, &c->iev);
156 	event_add(&c->iev.ev, NULL);
157 
158 	TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
159 }
160 
161 struct ctl_conn *
162 control_connbyfd(int fd)
163 {
164 	struct ctl_conn	*c;
165 
166 	for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.fd != fd;
167 	    c = TAILQ_NEXT(c, entry))
168 		;	/* nothing */
169 
170 	return (c);
171 }
172 
173 struct ctl_conn *
174 control_connbypid(pid_t pid)
175 {
176 	struct ctl_conn	*c;
177 
178 	for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.pid != pid;
179 	    c = TAILQ_NEXT(c, entry))
180 		;	/* nothing */
181 
182 	return (c);
183 }
184 
185 void
186 control_close(int fd)
187 {
188 	struct ctl_conn	*c;
189 
190 	if ((c = control_connbyfd(fd)) == NULL) {
191 		log_warn("control_close: fd %d: not found", fd);
192 		return;
193 	}
194 
195 	msgbuf_clear(&c->iev.ibuf.w);
196 	TAILQ_REMOVE(&ctl_conns, c, entry);
197 
198 	event_del(&c->iev.ev);
199 	close(c->iev.ibuf.fd);
200 
201 	/* Some file descriptors are available again. */
202 	if (evtimer_pending(&control_state.evt, NULL)) {
203 		evtimer_del(&control_state.evt);
204 		event_add(&control_state.ev, NULL);
205 	}
206 
207 	free(c);
208 }
209 
210 /* ARGSUSED */
211 void
212 control_dispatch_imsg(int fd, short event, void *bula)
213 {
214 	struct ctl_conn	*c;
215 	struct imsg	 imsg;
216 	ssize_t		 n;
217 	unsigned int	 ifidx;
218 	int		 verbose;
219 
220 	if ((c = control_connbyfd(fd)) == NULL) {
221 		log_warn("control_dispatch_imsg: fd %d: not found", fd);
222 		return;
223 	}
224 
225 	if (event & EV_READ) {
226 		if ((n = imsg_read(&c->iev.ibuf)) == -1 || n == 0) {
227 			control_close(fd);
228 			return;
229 		}
230 	}
231 	if (event & EV_WRITE) {
232 		if (msgbuf_write(&c->iev.ibuf.w) == -1) {
233 			control_close(fd);
234 			return;
235 		}
236 	}
237 
238 	for (;;) {
239 		if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
240 			control_close(fd);
241 			return;
242 		}
243 
244 		if (n == 0)
245 			break;
246 
247 		switch (imsg.hdr.type) {
248 		case IMSG_CTL_FIB_COUPLE:
249 		case IMSG_CTL_FIB_DECOUPLE:
250 			ospfe_fib_update(imsg.hdr.type);
251 			/* FALLTHROUGH */
252 		case IMSG_CTL_FIB_RELOAD:
253 		case IMSG_CTL_RELOAD:
254 			c->iev.ibuf.pid = imsg.hdr.pid;
255 			ospfe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0);
256 			break;
257 		case IMSG_CTL_KROUTE:
258 		case IMSG_CTL_KROUTE_ADDR:
259 		case IMSG_CTL_IFINFO:
260 			c->iev.ibuf.pid = imsg.hdr.pid;
261 			ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid,
262 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
263 			break;
264 		case IMSG_CTL_SHOW_INTERFACE:
265 			if (imsg.hdr.len == IMSG_HEADER_SIZE +
266 			    sizeof(ifidx)) {
267 				memcpy(&ifidx, imsg.data, sizeof(ifidx));
268 				ospfe_iface_ctl(c, ifidx);
269 				imsg_compose_event(&c->iev, IMSG_CTL_END, 0,
270 				    0, -1, NULL, 0);
271 			}
272 			break;
273 		case IMSG_CTL_SHOW_DATABASE:
274 		case IMSG_CTL_SHOW_DB_EXT:
275 		case IMSG_CTL_SHOW_DB_NET:
276 		case IMSG_CTL_SHOW_DB_RTR:
277 		case IMSG_CTL_SHOW_DB_SELF:
278 		case IMSG_CTL_SHOW_DB_SUM:
279 		case IMSG_CTL_SHOW_DB_ASBR:
280 		case IMSG_CTL_SHOW_DB_OPAQ:
281 		case IMSG_CTL_SHOW_RIB:
282 		case IMSG_CTL_SHOW_SUM:
283 			c->iev.ibuf.pid = imsg.hdr.pid;
284 			ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid,
285 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
286 			break;
287 		case IMSG_CTL_SHOW_NBR:
288 			ospfe_nbr_ctl(c);
289 			break;
290 		case IMSG_CTL_LOG_VERBOSE:
291 			if (imsg.hdr.len != IMSG_HEADER_SIZE +
292 			    sizeof(verbose))
293 				break;
294 
295 			/* forward to other processes */
296 			ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid,
297 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
298 			ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid,
299 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
300 
301 			memcpy(&verbose, imsg.data, sizeof(verbose));
302 			log_verbose(verbose);
303 			break;
304 		default:
305 			log_debug("control_dispatch_imsg: "
306 			    "error handling imsg %d", imsg.hdr.type);
307 			break;
308 		}
309 		imsg_free(&imsg);
310 	}
311 
312 	imsg_event_add(&c->iev);
313 }
314 
315 int
316 control_imsg_relay(struct imsg *imsg)
317 {
318 	struct ctl_conn	*c;
319 
320 	if ((c = control_connbypid(imsg->hdr.pid)) == NULL)
321 		return (0);
322 
323 	return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid,
324 	    -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE));
325 }
326 
327 void
328 session_socket_blockmode(int fd, enum blockmodes bm)
329 {
330 	int	flags;
331 
332 	if ((flags = fcntl(fd, F_GETFL, 0)) == -1)
333 		fatal("fcntl F_GETFL");
334 
335 	if (bm == BM_NONBLOCK)
336 		flags |= O_NONBLOCK;
337 	else
338 		flags &= ~O_NONBLOCK;
339 
340 	if ((flags = fcntl(fd, F_SETFL, flags)) == -1)
341 		fatal("fcntl F_SETFL");
342 }
343