xref: /openbsd/usr.sbin/dvmrpd/control.c (revision 404b540a)
1 /*	$OpenBSD: control.c,v 1.8 2009/06/06 07:52:04 pyr 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 int control_imsg_relay(struct imsg *imsg);
39 
40 struct ctl_conn	*control_connbyfd(int);
41 struct ctl_conn	*control_connbypid(pid_t);
42 void		 control_close(int);
43 
44 int
45 control_init(void)
46 {
47 	struct sockaddr_un	 sun;
48 	int			 fd;
49 	mode_t			 old_umask;
50 
51 	if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
52 		log_warn("control_init: socket");
53 		return (-1);
54 	}
55 
56 	bzero(&sun, sizeof(sun));
57 	sun.sun_family = AF_UNIX;
58 	strlcpy(sun.sun_path, DVMRPD_SOCKET, sizeof(sun.sun_path));
59 
60 	if (unlink(DVMRPD_SOCKET) == -1)
61 		if (errno != ENOENT) {
62 			log_warn("control_init: unlink %s", DVMRPD_SOCKET);
63 			close(fd);
64 			return (-1);
65 		}
66 
67 	old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
68 	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
69 		log_warn("control_init: bind: %s", DVMRPD_SOCKET);
70 		close(fd);
71 		umask(old_umask);
72 		return (-1);
73 	}
74 	umask(old_umask);
75 
76 	if (chmod(DVMRPD_SOCKET, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {
77 		log_warn("control_init: chmod");
78 		close(fd);
79 		(void)unlink(DVMRPD_SOCKET);
80 		return (-1);
81 	}
82 
83 	session_socket_blockmode(fd, BM_NONBLOCK);
84 	control_state.fd = fd;
85 
86 	return (0);
87 }
88 
89 int
90 control_listen(void)
91 {
92 
93 	if (listen(control_state.fd, CONTROL_BACKLOG) == -1) {
94 		log_warn("control_listen: listen");
95 		return (-1);
96 	}
97 
98 	event_set(&control_state.ev, control_state.fd, EV_READ | EV_PERSIST,
99 	    control_accept, NULL);
100 	event_add(&control_state.ev, NULL);
101 
102 	return (0);
103 }
104 
105 void
106 control_cleanup(void)
107 {
108 	unlink(DVMRPD_SOCKET);
109 }
110 
111 /* ARGSUSED */
112 void
113 control_accept(int listenfd, short event, void *bula)
114 {
115 	int			 connfd;
116 	socklen_t		 len;
117 	struct sockaddr_un	 sun;
118 	struct ctl_conn		*c;
119 
120 	len = sizeof(sun);
121 	if ((connfd = accept(listenfd,
122 	    (struct sockaddr *)&sun, &len)) == -1) {
123 		if (errno != EWOULDBLOCK && errno != EINTR)
124 			log_warn("control_accept");
125 		return;
126 	}
127 
128 	session_socket_blockmode(connfd, BM_NONBLOCK);
129 
130 	if ((c = malloc(sizeof(struct ctl_conn))) == NULL) {
131 		log_warn("control_accept");
132 		close(connfd);
133 		return;
134 	}
135 
136 	imsg_init(&c->iev.ibuf, connfd);
137 	c->iev.handler = control_dispatch_imsg;
138 	c->iev.events = EV_READ;
139 	event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events,
140 	    c->iev.handler, &c->iev);
141 	event_add(&c->iev.ev, NULL);
142 
143 	TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
144 }
145 
146 struct ctl_conn *
147 control_connbyfd(int fd)
148 {
149 	struct ctl_conn	*c;
150 
151 	for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.fd != fd;
152 	    c = TAILQ_NEXT(c, entry))
153 		;	/* nothing */
154 
155 	return (c);
156 }
157 
158 struct ctl_conn *
159 control_connbypid(pid_t pid)
160 {
161 	struct ctl_conn	*c;
162 
163 	for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.pid != pid;
164 	    c = TAILQ_NEXT(c, entry))
165 		;	/* nothing */
166 
167 	return (c);
168 }
169 
170 void
171 control_close(int fd)
172 {
173 	struct ctl_conn	*c;
174 
175 	if ((c = control_connbyfd(fd)) == NULL) {
176 		log_warn("control_close: fd %d: not found", fd);
177 		return;
178 	}
179 
180 	msgbuf_clear(&c->iev.ibuf.w);
181 	TAILQ_REMOVE(&ctl_conns, c, entry);
182 
183 	event_del(&c->iev.ev);
184 	close(c->iev.ibuf.fd);
185 	free(c);
186 }
187 
188 /* ARGSUSED */
189 void
190 control_dispatch_imsg(int fd, short event, void *bula)
191 {
192 	struct ctl_conn	*c;
193 	struct imsg	 imsg;
194 	int		 n;
195 	unsigned int	 ifidx;
196 
197 	if ((c = control_connbyfd(fd)) == NULL) {
198 		log_warn("control_dispatch_imsg: fd %d: not found", fd);
199 		return;
200 	}
201 
202 	if (event & EV_READ) {
203 		if ((n = imsg_read(&c->iev.ibuf)) == -1 || n == 0) {
204 			control_close(fd);
205 			return;
206 		}
207 	}
208 	if (event & EV_WRITE) {
209 		if (msgbuf_write(&c->iev.ibuf.w) == -1) {
210 			control_close(fd);
211 			return;
212 		}
213 	}
214 
215 	for (;;) {
216 		if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
217 			control_close(fd);
218 			return;
219 		}
220 
221 		if (n == 0)
222 			break;
223 
224 		switch (imsg.hdr.type) {
225 		case IMSG_CTL_MFC_COUPLE:
226 		case IMSG_CTL_MFC_DECOUPLE:
227 		case IMSG_CTL_RELOAD:
228 			dvmrpe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0);
229 			break;
230 		case IMSG_CTL_SHOW_IFACE:
231 			if (imsg.hdr.len == IMSG_HEADER_SIZE +
232 			    sizeof(ifidx)) {
233 				memcpy(&ifidx, imsg.data, sizeof(ifidx));
234 				dvmrpe_iface_ctl(c, ifidx);
235 				imsg_compose_event(&c->iev, IMSG_CTL_END, 0,
236 				    0, -1, NULL, 0);
237 			}
238 			break;
239 		case IMSG_CTL_SHOW_IGMP:
240 			if (imsg.hdr.len == IMSG_HEADER_SIZE +
241 			    sizeof(ifidx)) {
242 				memcpy(&ifidx, imsg.data, sizeof(ifidx));
243 				dvmrpe_iface_igmp_ctl(c, ifidx);
244 				imsg_compose_event(&c->iev, IMSG_CTL_END, 0,
245 				    0, -1, NULL, 0);
246 			}
247 			break;
248 		case IMSG_CTL_SHOW_NBR:
249 			dvmrpe_nbr_ctl(c);
250 			break;
251 		case IMSG_CTL_SHOW_RIB:
252 		case IMSG_CTL_SHOW_MFC:
253 		case IMSG_CTL_SHOW_SUM:
254 			c->iev.ibuf.pid = imsg.hdr.pid;
255 			dvmrpe_imsg_compose_rde(imsg.hdr.type, 0, imsg.hdr.pid,
256 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
257 			break;
258 		default:
259 			log_debug("control_dispatch_imsg: "
260 			    "error handling imsg %d", imsg.hdr.type);
261 			break;
262 		}
263 		imsg_free(&imsg);
264 	}
265 
266 	imsg_event_add(&c->iev);
267 }
268 
269 int
270 control_imsg_relay(struct imsg *imsg)
271 {
272 	struct ctl_conn	*c;
273 
274 	if ((c = control_connbypid(imsg->hdr.pid)) == NULL)
275 		return (0);
276 
277 	return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid,
278 	    -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE));
279 }
280 
281 void
282 session_socket_blockmode(int fd, enum blockmodes bm)
283 {
284 	int	flags;
285 
286 	if ((flags = fcntl(fd, F_GETFL, 0)) == -1)
287 		fatal("fcntl F_GETFL");
288 
289 	if (bm == BM_NONBLOCK)
290 		flags |= O_NONBLOCK;
291 	else
292 		flags &= ~O_NONBLOCK;
293 
294 	if ((flags = fcntl(fd, F_SETFL, flags)) == -1)
295 		fatal("fcntl F_SETFL");
296 }
297