1 /*	$OpenBSD$ */
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 <zebra.h>
20 #include <sys/un.h>
21 
22 #include "ldpd.h"
23 #include "ldpe.h"
24 #include "log.h"
25 #include "control.h"
26 
27 #define	CONTROL_BACKLOG	5
28 
29 static int		 control_accept(struct thread *);
30 static struct ctl_conn	*control_connbyfd(int);
31 static struct ctl_conn	*control_connbypid(pid_t);
32 static void		 control_close(int);
33 static int		 control_dispatch_imsg(struct thread *);
34 
35 struct ctl_conns	 ctl_conns;
36 
37 static int		 control_fd;
38 
39 int
control_init(char * path)40 control_init(char *path)
41 {
42 	struct sockaddr_un	 s_un;
43 	int			 fd;
44 	mode_t			 old_umask;
45 
46 	if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
47 		log_warn("%s: socket", __func__);
48 		return (-1);
49 	}
50 	sock_set_nonblock(fd);
51 
52 	memset(&s_un, 0, sizeof(s_un));
53 	s_un.sun_family = AF_UNIX;
54 	strlcpy(s_un.sun_path, path, sizeof(s_un.sun_path));
55 
56 	if (unlink(path) == -1)
57 		if (errno != ENOENT) {
58 			log_warn("%s: unlink %s", __func__, path);
59 			close(fd);
60 			return (-1);
61 		}
62 
63 	old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
64 	if (bind(fd, (struct sockaddr *)&s_un, sizeof(s_un)) == -1) {
65 		log_warn("%s: bind: %s", __func__, path);
66 		close(fd);
67 		umask(old_umask);
68 		return (-1);
69 	}
70 	umask(old_umask);
71 
72 	if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {
73 		log_warn("%s: chmod", __func__);
74 		close(fd);
75 		(void)unlink(path);
76 		return (-1);
77 	}
78 
79 	control_fd = fd;
80 
81 	return (0);
82 }
83 
84 int
control_listen(void)85 control_listen(void)
86 {
87 	if (listen(control_fd, CONTROL_BACKLOG) == -1) {
88 		log_warn("%s: listen", __func__);
89 		return (-1);
90 	}
91 
92 	return (accept_add(control_fd, control_accept, NULL));
93 }
94 
95 void
control_cleanup(char * path)96 control_cleanup(char *path)
97 {
98 	accept_del(control_fd);
99 	close(control_fd);
100 	unlink(path);
101 }
102 
103 /* ARGSUSED */
104 static int
control_accept(struct thread * thread)105 control_accept(struct thread *thread)
106 {
107 	int			 connfd;
108 	socklen_t		 len;
109 	struct sockaddr_un	 s_un;
110 	struct ctl_conn		*c;
111 
112 	len = sizeof(s_un);
113 	if ((connfd = accept(THREAD_FD(thread), (struct sockaddr *)&s_un,
114 	    &len)) == -1) {
115 		/*
116 		 * Pause accept if we are out of file descriptors, or
117 		 * libevent will haunt us here too.
118 		 */
119 		if (errno == ENFILE || errno == EMFILE)
120 			accept_pause();
121 		else if (errno != EWOULDBLOCK && errno != EINTR &&
122 		    errno != ECONNABORTED)
123 			log_warn("%s: accept", __func__);
124 		return (0);
125 	}
126 	sock_set_nonblock(connfd);
127 
128 	if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {
129 		log_warn(__func__);
130 		close(connfd);
131 		return (0);
132 	}
133 
134 	imsg_init(&c->iev.ibuf, connfd);
135 	c->iev.handler_read = control_dispatch_imsg;
136 	c->iev.ev_read = NULL;
137 	thread_add_read(master, c->iev.handler_read, &c->iev, c->iev.ibuf.fd,
138 			&c->iev.ev_read);
139 	c->iev.handler_write = ldp_write_handler;
140 	c->iev.ev_write = NULL;
141 
142 	TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
143 
144 	return (0);
145 }
146 
147 static struct ctl_conn *
control_connbyfd(int fd)148 control_connbyfd(int fd)
149 {
150 	struct ctl_conn	*c;
151 
152 	TAILQ_FOREACH(c, &ctl_conns, entry) {
153 		if (c->iev.ibuf.fd == fd)
154 			break;
155 	}
156 
157 	return (c);
158 }
159 
160 static struct ctl_conn *
control_connbypid(pid_t pid)161 control_connbypid(pid_t pid)
162 {
163 	struct ctl_conn	*c;
164 
165 	TAILQ_FOREACH(c, &ctl_conns, entry) {
166 		if (c->iev.ibuf.pid == pid)
167 			break;
168 	}
169 
170 	return (c);
171 }
172 
173 static void
control_close(int fd)174 control_close(int fd)
175 {
176 	struct ctl_conn	*c;
177 
178 	if ((c = control_connbyfd(fd)) == NULL) {
179 		log_warnx("%s: fd %d: not found", __func__, fd);
180 		return;
181 	}
182 
183 	msgbuf_clear(&c->iev.ibuf.w);
184 	TAILQ_REMOVE(&ctl_conns, c, entry);
185 
186 	THREAD_READ_OFF(c->iev.ev_read);
187 	THREAD_WRITE_OFF(c->iev.ev_write);
188 	close(c->iev.ibuf.fd);
189 	accept_unpause();
190 	free(c);
191 }
192 
193 /* ARGSUSED */
194 static int
control_dispatch_imsg(struct thread * thread)195 control_dispatch_imsg(struct thread *thread)
196 {
197 	int		 fd = THREAD_FD(thread);
198 	struct ctl_conn	*c;
199 	struct imsg	 imsg;
200 	ssize_t		 n;
201 	unsigned int	 ifidx;
202 
203 	if ((c = control_connbyfd(fd)) == NULL) {
204 		log_warnx("%s: fd %d: not found", __func__, fd);
205 		return (0);
206 	}
207 
208 	c->iev.ev_read = NULL;
209 
210 	if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) ||
211 	    n == 0) {
212 		control_close(fd);
213 		return (0);
214 	}
215 
216 	for (;;) {
217 		if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
218 			control_close(fd);
219 			return (0);
220 		}
221 
222 		if (n == 0)
223 			break;
224 
225 		switch (imsg.hdr.type) {
226 		case IMSG_CTL_FIB_COUPLE:
227 		case IMSG_CTL_FIB_DECOUPLE:
228 		case IMSG_CTL_RELOAD:
229 		case IMSG_CTL_KROUTE:
230 		case IMSG_CTL_KROUTE_ADDR:
231 		case IMSG_CTL_IFINFO:
232 			/* ignore */
233 			break;
234 		case IMSG_CTL_SHOW_INTERFACE:
235 			if (imsg.hdr.len == IMSG_HEADER_SIZE +
236 			    sizeof(ifidx)) {
237 				memcpy(&ifidx, imsg.data, sizeof(ifidx));
238 				ldpe_iface_ctl(c, ifidx);
239 				imsg_compose_event(&c->iev, IMSG_CTL_END, 0,
240 				    0, -1, NULL, 0);
241 			}
242 			break;
243 		case IMSG_CTL_SHOW_DISCOVERY:
244 			ldpe_adj_ctl(c);
245 			break;
246 		case IMSG_CTL_SHOW_DISCOVERY_DTL:
247 			ldpe_adj_detail_ctl(c);
248 			break;
249 		case IMSG_CTL_SHOW_LIB:
250 		case IMSG_CTL_SHOW_L2VPN_PW:
251 		case IMSG_CTL_SHOW_L2VPN_BINDING:
252 			c->iev.ibuf.pid = imsg.hdr.pid;
253 			ldpe_imsg_compose_lde(imsg.hdr.type, 0, imsg.hdr.pid,
254 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
255 			break;
256 		case IMSG_CTL_SHOW_NBR:
257 			ldpe_nbr_ctl(c);
258 			break;
259 		case IMSG_CTL_CLEAR_NBR:
260 			if (imsg.hdr.len != IMSG_HEADER_SIZE +
261 			    sizeof(struct ctl_nbr))
262 				break;
263 
264 			nbr_clear_ctl(imsg.data);
265 			break;
266 		case IMSG_CTL_LOG_VERBOSE:
267 			/* ignore */
268 			break;
269 		default:
270 			log_debug("%s: error handling imsg %d", __func__,
271 			    imsg.hdr.type);
272 			break;
273 		}
274 		imsg_free(&imsg);
275 	}
276 
277 	imsg_event_add(&c->iev);
278 
279 	return (0);
280 }
281 
282 int
control_imsg_relay(struct imsg * imsg)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