xref: /openbsd-src/usr.sbin/dvmrpd/control.c (revision d13be5d47e4149db2549a9828e244d59dbc43f15)
1 /*	$OpenBSD: control.c,v 1.14 2010/09/02 14:03:21 sobrado 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 "igmp.h"
30 #include "dvmrpd.h"
31 #include "dvmrp.h"
32 #include "dvmrpe.h"
33 #include "log.h"
34 #include "control.h"
35 
36 #define	CONTROL_BACKLOG	5
37 
38 struct ctl_conn	*control_connbyfd(int);
39 struct ctl_conn	*control_connbypid(pid_t);
40 void		 control_close(int);
41 
42 int
43 control_init(void)
44 {
45 	struct sockaddr_un	 sun;
46 	int			 fd;
47 	mode_t			 old_umask;
48 
49 	if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
50 		log_warn("control_init: socket");
51 		return (-1);
52 	}
53 
54 	bzero(&sun, sizeof(sun));
55 	sun.sun_family = AF_UNIX;
56 	strlcpy(sun.sun_path, DVMRPD_SOCKET, sizeof(sun.sun_path));
57 
58 	if (unlink(DVMRPD_SOCKET) == -1)
59 		if (errno != ENOENT) {
60 			log_warn("control_init: unlink %s", DVMRPD_SOCKET);
61 			close(fd);
62 			return (-1);
63 		}
64 
65 	old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
66 	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
67 		log_warn("control_init: bind: %s", DVMRPD_SOCKET);
68 		close(fd);
69 		umask(old_umask);
70 		return (-1);
71 	}
72 	umask(old_umask);
73 
74 	if (chmod(DVMRPD_SOCKET, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {
75 		log_warn("control_init: chmod");
76 		close(fd);
77 		(void)unlink(DVMRPD_SOCKET);
78 		return (-1);
79 	}
80 
81 	session_socket_blockmode(fd, BM_NONBLOCK);
82 	control_state.fd = fd;
83 
84 	return (0);
85 }
86 
87 int
88 control_listen(void)
89 {
90 
91 	if (listen(control_state.fd, CONTROL_BACKLOG) == -1) {
92 		log_warn("control_listen: listen");
93 		return (-1);
94 	}
95 
96 	event_set(&control_state.ev, control_state.fd, EV_READ | EV_PERSIST,
97 	    control_accept, NULL);
98 	event_add(&control_state.ev, NULL);
99 
100 	return (0);
101 }
102 
103 void
104 control_cleanup(void)
105 {
106 	unlink(DVMRPD_SOCKET);
107 }
108 
109 /* ARGSUSED */
110 void
111 control_accept(int listenfd, short event, void *bula)
112 {
113 	int			 connfd;
114 	socklen_t		 len;
115 	struct sockaddr_un	 sun;
116 	struct ctl_conn		*c;
117 
118 	len = sizeof(sun);
119 	if ((connfd = accept(listenfd,
120 	    (struct sockaddr *)&sun, &len)) == -1) {
121 		if (errno != EWOULDBLOCK && errno != EINTR)
122 			log_warn("control_accept: accept");
123 		return;
124 	}
125 
126 	session_socket_blockmode(connfd, BM_NONBLOCK);
127 
128 	if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {
129 		log_warn("control_accept");
130 		close(connfd);
131 		return;
132 	}
133 
134 	imsg_init(&c->iev.ibuf, connfd);
135 	c->iev.handler = control_dispatch_imsg;
136 	c->iev.events = EV_READ;
137 	event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events,
138 	    c->iev.handler, &c->iev);
139 	event_add(&c->iev.ev, NULL);
140 
141 	TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
142 }
143 
144 struct ctl_conn *
145 control_connbyfd(int fd)
146 {
147 	struct ctl_conn	*c;
148 
149 	for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.fd != fd;
150 	    c = TAILQ_NEXT(c, entry))
151 		;	/* nothing */
152 
153 	return (c);
154 }
155 
156 struct ctl_conn *
157 control_connbypid(pid_t pid)
158 {
159 	struct ctl_conn	*c;
160 
161 	for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.pid != pid;
162 	    c = TAILQ_NEXT(c, entry))
163 		;	/* nothing */
164 
165 	return (c);
166 }
167 
168 void
169 control_close(int fd)
170 {
171 	struct ctl_conn	*c;
172 
173 	if ((c = control_connbyfd(fd)) == NULL) {
174 		log_warn("control_close: fd %d: not found", fd);
175 		return;
176 	}
177 
178 	msgbuf_clear(&c->iev.ibuf.w);
179 	TAILQ_REMOVE(&ctl_conns, c, entry);
180 
181 	event_del(&c->iev.ev);
182 	close(c->iev.ibuf.fd);
183 	free(c);
184 }
185 
186 /* ARGSUSED */
187 void
188 control_dispatch_imsg(int fd, short event, void *bula)
189 {
190 	struct ctl_conn	*c;
191 	struct imsg	 imsg;
192 	int		 n;
193 	unsigned int	 ifidx;
194 	int		 verbose;
195 
196 	if ((c = control_connbyfd(fd)) == NULL) {
197 		log_warn("control_dispatch_imsg: fd %d: not found", fd);
198 		return;
199 	}
200 
201 	if (event & EV_READ) {
202 		if ((n = imsg_read(&c->iev.ibuf)) == -1 || n == 0) {
203 			control_close(fd);
204 			return;
205 		}
206 	}
207 	if (event & EV_WRITE) {
208 		if (msgbuf_write(&c->iev.ibuf.w) == -1) {
209 			control_close(fd);
210 			return;
211 		}
212 	}
213 
214 	for (;;) {
215 		if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
216 			control_close(fd);
217 			return;
218 		}
219 
220 		if (n == 0)
221 			break;
222 
223 		switch (imsg.hdr.type) {
224 		case IMSG_CTL_MFC_COUPLE:
225 		case IMSG_CTL_MFC_DECOUPLE:
226 		case IMSG_CTL_RELOAD:
227 			dvmrpe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0);
228 			break;
229 		case IMSG_CTL_SHOW_IFACE:
230 			if (imsg.hdr.len == IMSG_HEADER_SIZE +
231 			    sizeof(ifidx)) {
232 				memcpy(&ifidx, imsg.data, sizeof(ifidx));
233 				dvmrpe_iface_ctl(c, ifidx);
234 				imsg_compose_event(&c->iev, IMSG_CTL_END, 0,
235 				    0, -1, NULL, 0);
236 			}
237 			break;
238 		case IMSG_CTL_SHOW_IGMP:
239 			if (imsg.hdr.len == IMSG_HEADER_SIZE +
240 			    sizeof(ifidx)) {
241 				memcpy(&ifidx, imsg.data, sizeof(ifidx));
242 				dvmrpe_iface_igmp_ctl(c, ifidx);
243 				imsg_compose_event(&c->iev, IMSG_CTL_END, 0,
244 				    0, -1, NULL, 0);
245 			}
246 			break;
247 		case IMSG_CTL_SHOW_NBR:
248 			dvmrpe_nbr_ctl(c);
249 			break;
250 		case IMSG_CTL_SHOW_RIB:
251 		case IMSG_CTL_SHOW_MFC:
252 		case IMSG_CTL_SHOW_SUM:
253 			c->iev.ibuf.pid = imsg.hdr.pid;
254 			dvmrpe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid,
255 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
256 			break;
257 		case IMSG_CTL_LOG_VERBOSE:
258 			if (imsg.hdr.len != IMSG_HEADER_SIZE +
259 			    sizeof(verbose))
260 				break;
261 
262 			/* forward to other processes */
263 			dvmrpe_imsg_compose_parent(imsg.hdr.type, imsg.hdr.pid,
264 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
265 			dvmrpe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid,
266 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
267 
268 			memcpy(&verbose, imsg.data, sizeof(verbose));
269 			log_verbose(verbose);
270 			break;
271 		default:
272 			log_debug("control_dispatch_imsg: "
273 			    "error handling imsg %d", imsg.hdr.type);
274 			break;
275 		}
276 		imsg_free(&imsg);
277 	}
278 
279 	imsg_event_add(&c->iev);
280 }
281 
282 int
283 control_imsg_relay(struct imsg *imsg)
284 {
285 	struct ctl_conn	*c;
286 
287 	if ((c = control_connbypid(imsg->hdr.pid)) == NULL)
288 		return (0);
289 
290 	return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid,
291 	    -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE));
292 }
293 
294 void
295 session_socket_blockmode(int fd, enum blockmodes bm)
296 {
297 	int	flags;
298 
299 	if ((flags = fcntl(fd, F_GETFL, 0)) == -1)
300 		fatal("fcntl F_GETFL");
301 
302 	if (bm == BM_NONBLOCK)
303 		flags |= O_NONBLOCK;
304 	else
305 		flags &= ~O_NONBLOCK;
306 
307 	if ((flags = fcntl(fd, F_SETFL, flags)) == -1)
308 		fatal("fcntl F_SETFL");
309 }
310