xref: /openbsd-src/usr.sbin/ospf6d/control.c (revision ac9b4aacc1da35008afea06a5d23c2f2dea9b93e)
1 /*	$OpenBSD: control.c,v 1.18 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 "ospf6d.h"
30 #include "ospf6.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(void)
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, OSPF6D_SOCKET, sizeof(sun.sun_path));
56 
57 	if (unlink(OSPF6D_SOCKET) == -1)
58 		if (errno != ENOENT) {
59 			log_warn("control_init: unlink %s", OSPF6D_SOCKET);
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", OSPF6D_SOCKET);
67 		close(fd);
68 		umask(old_umask);
69 		return (-1);
70 	}
71 	umask(old_umask);
72 
73 	if (chmod(OSPF6D_SOCKET, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {
74 		log_warn("control_init: chmod");
75 		close(fd);
76 		(void)unlink(OSPF6D_SOCKET);
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 	if (listen(control_state.fd, CONTROL_BACKLOG) == -1) {
90 		log_warn("control_listen: listen");
91 		return (-1);
92 	}
93 
94 	event_set(&control_state.ev, control_state.fd, EV_READ,
95 	    control_accept, NULL);
96 	event_add(&control_state.ev, NULL);
97 	evtimer_set(&control_state.evt, control_accept, NULL);
98 
99 	return (0);
100 }
101 
102 void
103 control_cleanup(void)
104 {
105 	event_del(&control_state.ev);
106 	event_del(&control_state.evt);
107 	unlink(OSPF6D_SOCKET);
108 }
109 
110 /* ARGSUSED */
111 void
112 control_accept(int listenfd, short event, void *bula)
113 {
114 	int			 connfd;
115 	socklen_t		 len;
116 	struct sockaddr_un	 sun;
117 	struct ctl_conn		*c;
118 
119 	event_add(&control_state.ev, NULL);
120 	if ((event & EV_TIMEOUT))
121 		return;
122 
123 	len = sizeof(sun);
124 	if ((connfd = accept(listenfd,
125 	    (struct sockaddr *)&sun, &len)) == -1) {
126 		/*
127 		 * Pause accept if we are out of file descriptors, or
128 		 * libevent will haunt us here too.
129 		 */
130 		if (errno == ENFILE || errno == EMFILE) {
131 			struct timeval evtpause = { 1, 0 };
132 
133 			event_del(&control_state.ev);
134 			evtimer_add(&control_state.evt, &evtpause);
135 		} else if (errno != EWOULDBLOCK && errno != EINTR)
136 			log_warn("control_accept: accept");
137 		return;
138 	}
139 
140 	session_socket_blockmode(connfd, BM_NONBLOCK);
141 
142 	if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {
143 		log_warn("control_accept");
144 		close(connfd);
145 		return;
146 	}
147 
148 	imsg_init(&c->iev.ibuf, connfd);
149 	c->iev.handler = control_dispatch_imsg;
150 	c->iev.events = EV_READ;
151 	event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events,
152 	    c->iev.handler, &c->iev);
153 	event_add(&c->iev.ev, NULL);
154 
155 	TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
156 }
157 
158 struct ctl_conn *
159 control_connbyfd(int fd)
160 {
161 	struct ctl_conn	*c;
162 
163 	for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.fd != fd;
164 	    c = TAILQ_NEXT(c, entry))
165 		;	/* nothing */
166 
167 	return (c);
168 }
169 
170 struct ctl_conn *
171 control_connbypid(pid_t pid)
172 {
173 	struct ctl_conn	*c;
174 
175 	for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.pid != pid;
176 	    c = TAILQ_NEXT(c, entry))
177 		;	/* nothing */
178 
179 	return (c);
180 }
181 
182 void
183 control_close(int fd)
184 {
185 	struct ctl_conn	*c;
186 
187 	if ((c = control_connbyfd(fd)) == NULL) {
188 		log_warn("control_close: fd %d: not found", fd);
189 		return;
190 	}
191 
192 	msgbuf_clear(&c->iev.ibuf.w);
193 	TAILQ_REMOVE(&ctl_conns, c, entry);
194 
195 	event_del(&c->iev.ev);
196 	close(c->iev.ibuf.fd);
197 
198 	/* Some file descriptors are available again. */
199 	if (evtimer_pending(&control_state.evt, NULL)) {
200 		evtimer_del(&control_state.evt);
201 		event_add(&control_state.ev, NULL);
202 	}
203 
204 	free(c);
205 }
206 
207 /* ARGSUSED */
208 void
209 control_dispatch_imsg(int fd, short event, void *bula)
210 {
211 	struct ctl_conn	*c;
212 	struct imsg	 imsg;
213 	int		 n;
214 	unsigned int	 ifidx;
215 	int		 verbose;
216 
217 	if ((c = control_connbyfd(fd)) == NULL) {
218 		log_warn("control_dispatch_imsg: fd %d: not found", fd);
219 		return;
220 	}
221 
222 	if (event & EV_READ) {
223 		if ((n = imsg_read(&c->iev.ibuf)) == -1 || n == 0) {
224 			control_close(fd);
225 			return;
226 		}
227 	}
228 	if (event & EV_WRITE) {
229 		if (msgbuf_write(&c->iev.ibuf.w) == -1) {
230 			control_close(fd);
231 			return;
232 		}
233 	}
234 
235 	for (;;) {
236 		if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
237 			control_close(fd);
238 			return;
239 		}
240 
241 		if (n == 0)
242 			break;
243 
244 		switch (imsg.hdr.type) {
245 		case IMSG_CTL_FIB_COUPLE:
246 		case IMSG_CTL_FIB_DECOUPLE:
247 			ospfe_fib_update(imsg.hdr.type);
248 			/* FALLTHROUGH */
249 		case IMSG_CTL_RELOAD:
250 			c->iev.ibuf.pid = imsg.hdr.pid;
251 			ospfe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0);
252 			break;
253 		case IMSG_CTL_KROUTE:
254 		case IMSG_CTL_KROUTE_ADDR:
255 			c->iev.ibuf.pid = imsg.hdr.pid;
256 			ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid,
257 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
258 			break;
259 		case IMSG_CTL_SHOW_INTERFACE:
260 			if (imsg.hdr.len == IMSG_HEADER_SIZE +
261 			    sizeof(ifidx)) {
262 				memcpy(&ifidx, imsg.data, sizeof(ifidx));
263 				ospfe_iface_ctl(c, ifidx);
264 				imsg_compose(&c->iev.ibuf, IMSG_CTL_END, 0,
265 				    0, -1, NULL, 0);
266 			}
267 			break;
268 		case IMSG_CTL_SHOW_DATABASE:
269 		case IMSG_CTL_SHOW_DB_EXT:
270 		case IMSG_CTL_SHOW_DB_LINK:
271 		case IMSG_CTL_SHOW_DB_NET:
272 		case IMSG_CTL_SHOW_DB_RTR:
273 		case IMSG_CTL_SHOW_DB_INTRA:
274 		case IMSG_CTL_SHOW_DB_SELF:
275 		case IMSG_CTL_SHOW_DB_SUM:
276 		case IMSG_CTL_SHOW_DB_ASBR:
277 		case IMSG_CTL_SHOW_RIB:
278 		case IMSG_CTL_SHOW_SUM:
279 			c->iev.ibuf.pid = imsg.hdr.pid;
280 			ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid,
281 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
282 			break;
283 		case IMSG_CTL_SHOW_NBR:
284 			ospfe_nbr_ctl(c);
285 			break;
286 		case IMSG_CTL_LOG_VERBOSE:
287 			if (imsg.hdr.len != IMSG_HEADER_SIZE +
288 			    sizeof(verbose))
289 				break;
290 
291 			/* forward to other processes */
292 			ospfe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid,
293 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
294 			ospfe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid,
295 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
296 
297 			memcpy(&verbose, imsg.data, sizeof(verbose));
298 			log_verbose(verbose);
299 			break;
300 		default:
301 			log_debug("control_dispatch_imsg: "
302 			    "error handling imsg %d", imsg.hdr.type);
303 			break;
304 		}
305 		imsg_free(&imsg);
306 	}
307 
308 	imsg_event_add(&c->iev);
309 }
310 
311 int
312 control_imsg_relay(struct imsg *imsg)
313 {
314 	struct ctl_conn	*c;
315 
316 	if ((c = control_connbypid(imsg->hdr.pid)) == NULL)
317 		return (0);
318 
319 	return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid,
320 	    -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE));
321 }
322 
323 void
324 session_socket_blockmode(int fd, enum blockmodes bm)
325 {
326 	int	flags;
327 
328 	if ((flags = fcntl(fd, F_GETFL, 0)) == -1)
329 		fatal("fcntl F_GETFL");
330 
331 	if (bm == BM_NONBLOCK)
332 		flags |= O_NONBLOCK;
333 	else
334 		flags &= ~O_NONBLOCK;
335 
336 	if ((flags = fcntl(fd, F_SETFL, flags)) == -1)
337 		fatal("fcntl F_SETFL");
338 }
339