xref: /openbsd-src/usr.sbin/ripd/control.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenBSD: control.c,v 1.7 2009/02/25 17:09:55 claudio 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 "ripd.h"
30 #include "rip.h"
31 #include "ripe.h"
32 #include "log.h"
33 #include "control.h"
34 
35 #define	CONTROL_BACKLOG	5
36 
37 int control_imsg_relay(struct imsg *imsg);
38 
39 struct ctl_conn	*control_connbyfd(int);
40 struct ctl_conn	*control_connbypid(pid_t);
41 void		 control_close(int);
42 
43 int
44 control_init(void)
45 {
46 	struct sockaddr_un	 sun;
47 	int			 fd;
48 	mode_t			 old_umask;
49 
50 	if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
51 		log_warn("control_init: socket");
52 		return (-1);
53 	}
54 
55 	bzero(&sun, sizeof(sun));
56 	sun.sun_family = AF_UNIX;
57 	strlcpy(sun.sun_path, RIPD_SOCKET, sizeof(sun.sun_path));
58 
59 	if (unlink(RIPD_SOCKET) == -1)
60 		if (errno != ENOENT) {
61 			log_warn("control_init: unlink %s", RIPD_SOCKET);
62 			close(fd);
63 			return (-1);
64 		}
65 
66 	old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
67 	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
68 		log_warn("control_init: bind: %s", RIPD_SOCKET);
69 		close(fd);
70 		umask(old_umask);
71 		return (-1);
72 	}
73 	umask(old_umask);
74 
75 	if (chmod(RIPD_SOCKET, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {
76 		log_warn("control_init: chmod");
77 		close(fd);
78 		(void)unlink(RIPD_SOCKET);
79 		return (-1);
80 	}
81 
82 	session_socket_blockmode(fd, BM_NONBLOCK);
83 	control_state.fd = fd;
84 
85 	return (0);
86 }
87 
88 int
89 control_listen(void)
90 {
91 
92 	if (listen(control_state.fd, CONTROL_BACKLOG) == -1) {
93 		log_warn("control_listen: listen");
94 		return (-1);
95 	}
96 
97 	event_set(&control_state.ev, control_state.fd, EV_READ | EV_PERSIST,
98 	    control_accept, NULL);
99 	event_add(&control_state.ev, NULL);
100 
101 	return (0);
102 }
103 
104 void
105 control_cleanup(void)
106 {
107 	unlink(RIPD_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 	len = sizeof(sun);
120 	if ((connfd = accept(listenfd,
121 	    (struct sockaddr *)&sun, &len)) == -1) {
122 		if (errno != EWOULDBLOCK && errno != EINTR)
123 			log_warn("control_accept");
124 		return;
125 	}
126 
127 	session_socket_blockmode(connfd, BM_NONBLOCK);
128 
129 	if ((c = malloc(sizeof(struct ctl_conn))) == NULL) {
130 		log_warn("control_accept");
131 		close(connfd);
132 		return;
133 	}
134 
135 	imsg_init(&c->ibuf, connfd, control_dispatch_imsg);
136 	c->ibuf.events = EV_READ;
137 	event_set(&c->ibuf.ev, c->ibuf.fd, c->ibuf.events,
138 	    c->ibuf.handler, &c->ibuf);
139 	event_add(&c->ibuf.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->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->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->ibuf.w);
179 	TAILQ_REMOVE(&ctl_conns, c, entry);
180 
181 	event_del(&c->ibuf.ev);
182 	close(c->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 	ssize_t		 n;
193 	unsigned int	 ifidx;
194 
195 	if ((c = control_connbyfd(fd)) == NULL) {
196 		log_warn("control_dispatch_imsg: fd %d: not found", fd);
197 		return;
198 	}
199 
200 	switch (event) {
201 	case EV_READ:
202 		if ((n = imsg_read(&c->ibuf)) == -1 || n == 0) {
203 			control_close(fd);
204 			return;
205 		}
206 		break;
207 	case EV_WRITE:
208 		if (msgbuf_write(&c->ibuf.w) < 0) {
209 			control_close(fd);
210 			return;
211 		}
212 		imsg_event_add(&c->ibuf);
213 		return;
214 	default:
215 		fatalx("unknown event");
216 	}
217 
218 	for (;;) {
219 		if ((n = imsg_get(&c->ibuf, &imsg)) == -1) {
220 			control_close(fd);
221 			return;
222 		}
223 
224 		if (n == 0)
225 			break;
226 
227 		switch (imsg.hdr.type) {
228 		case IMSG_CTL_SHOW_INTERFACE:
229 			if (imsg.hdr.len - IMSG_HEADER_SIZE != sizeof(ifidx))
230 				return;
231 
232 			memcpy(&ifidx, imsg.data, sizeof(ifidx));
233 			ripe_iface_ctl(c, ifidx);
234 			imsg_compose(&c->ibuf, IMSG_CTL_END, 0, 0, NULL, 0);
235 
236 			break;
237 		case IMSG_CTL_SHOW_RIB:
238 			c->ibuf.pid = imsg.hdr.pid;
239 			ripe_imsg_compose_rde(imsg.hdr.type, 0,
240 			    imsg.hdr.pid, imsg.data, imsg.hdr.len -
241 			    IMSG_HEADER_SIZE);
242 			break;
243 		case IMSG_CTL_SHOW_NBR:
244 			ripe_nbr_ctl(c);
245 			break;
246 		case IMSG_CTL_KROUTE_ADDR:
247 		case IMSG_CTL_KROUTE:
248 		case IMSG_CTL_IFINFO:
249 			c->ibuf.pid = imsg.hdr.pid;
250 			ripe_imsg_compose_parent(imsg.hdr.type,
251 			    imsg.hdr.pid, imsg.data,
252 			    imsg.hdr.len - IMSG_HEADER_SIZE);
253 			break;
254 		case IMSG_CTL_FIB_COUPLE:
255 		case IMSG_CTL_FIB_DECOUPLE:
256 		case IMSG_CTL_RELOAD:
257 			c->ibuf.pid = imsg.hdr.pid;
258 			ripe_imsg_compose_parent(imsg.hdr.type, 0, NULL, 0);
259 			break;
260 		default:
261 			log_debug("control_dispatch_imsg: "
262 			    "error handling imsg %d", imsg.hdr.type);
263 			break;
264 		}
265 		imsg_free(&imsg);
266 	}
267 
268 	imsg_event_add(&c->ibuf);
269 }
270 
271 int
272 control_imsg_relay(struct imsg *imsg)
273 {
274 	struct ctl_conn	*c;
275 
276 	if ((c = control_connbypid(imsg->hdr.pid)) == NULL)
277 		return (0);
278 
279 	return (imsg_compose(&c->ibuf, imsg->hdr.type, 0, imsg->hdr.pid,
280 	    imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE));
281 }
282 
283 void
284 session_socket_blockmode(int fd, enum blockmodes bm)
285 {
286 	int	flags;
287 
288 	if ((flags = fcntl(fd, F_GETFL, 0)) == -1)
289 		fatal("fcntl F_GETFL");
290 
291 	if (bm == BM_NONBLOCK)
292 		flags |= O_NONBLOCK;
293 	else
294 		flags &= ~O_NONBLOCK;
295 
296 	if ((flags = fcntl(fd, F_SETFL, flags)) == -1)
297 		fatal("fcntl F_SETFL");
298 }
299