control.c revision 1.14 
1/*	$OpenBSD: control.c,v 1.14 2014/04/22 12:00:03 reyk Exp $	*/
2
3/*
4 * Copyright (c) 2010-2013 Reyk Floeter <reyk@openbsd.org>
5 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 */
19
20#include <sys/queue.h>
21#include <sys/param.h>
22#include <sys/stat.h>
23#include <sys/socket.h>
24#include <sys/un.h>
25#include <sys/tree.h>
26
27#include <net/if.h>
28
29#include <errno.h>
30#include <event.h>
31#include <fcntl.h>
32#include <stdlib.h>
33#include <string.h>
34#include <unistd.h>
35#include <signal.h>
36
37#include "iked.h"
38
39#define	CONTROL_BACKLOG	5
40
41struct ctl_connlist ctl_conns;
42
43void
44	 control_accept(int, short, void *);
45struct ctl_conn
46	*control_connbyfd(int);
47void	 control_close(int, struct control_sock *);
48void	 control_dispatch_imsg(int, short, void *);
49void	 control_imsg_forward(struct imsg *);
50
51int
52control_init(struct privsep *ps, struct control_sock *cs)
53{
54	struct iked		*env = ps->ps_env;
55	struct sockaddr_un	 sun;
56	int			 fd;
57	mode_t			 old_umask, mode;
58
59	if (cs->cs_name == NULL)
60		return (0);
61
62	if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
63		log_warn("%s: socket", __func__);
64		return (-1);
65	}
66
67	sun.sun_family = AF_UNIX;
68	if (strlcpy(sun.sun_path, cs->cs_name,
69	    sizeof(sun.sun_path)) >= sizeof(sun.sun_path)) {
70		log_warn("%s: %s name too long", __func__, cs->cs_name);
71		close(fd);
72		return (-1);
73	}
74
75	if (unlink(cs->cs_name) == -1)
76		if (errno != ENOENT) {
77			log_warn("%s: unlink %s", __func__, cs->cs_name);
78			close(fd);
79			return (-1);
80		}
81
82	if (cs->cs_restricted) {
83		old_umask = umask(S_IXUSR|S_IXGRP|S_IXOTH);
84		mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH;
85	} else {
86		old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
87		mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP;
88	}
89
90	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
91		log_warn("%s: bind: %s", __func__, cs->cs_name);
92		close(fd);
93		(void)umask(old_umask);
94		return (-1);
95	}
96	(void)umask(old_umask);
97
98	if (chmod(cs->cs_name, mode) == -1) {
99		log_warn("%s: chmod", __func__);
100		close(fd);
101		(void)unlink(cs->cs_name);
102		return (-1);
103	}
104
105	socket_set_blockmode(fd, BM_NONBLOCK);
106	cs->cs_fd = fd;
107	cs->cs_env = env;
108
109	return (0);
110}
111
112int
113control_listen(struct control_sock *cs)
114{
115	if (cs->cs_name == NULL)
116		return (0);
117
118	if (listen(cs->cs_fd, CONTROL_BACKLOG) == -1) {
119		log_warn("%s: listen", __func__);
120		return (-1);
121	}
122
123	event_set(&cs->cs_ev, cs->cs_fd, EV_READ,
124	    control_accept, cs);
125	event_add(&cs->cs_ev, NULL);
126	evtimer_set(&cs->cs_evt, control_accept, cs);
127
128	return (0);
129}
130
131void
132control_cleanup(struct control_sock *cs)
133{
134	if (cs->cs_name == NULL)
135		return;
136	event_del(&cs->cs_ev);
137	event_del(&cs->cs_evt);
138	(void)unlink(cs->cs_name);
139}
140
141/* ARGSUSED */
142void
143control_accept(int listenfd, short event, void *arg)
144{
145	struct control_sock	*cs = arg;
146	int			 connfd;
147	socklen_t		 len;
148	struct sockaddr_un	 sun;
149	struct ctl_conn		*c;
150
151	event_add(&cs->cs_ev, NULL);
152	if ((event & EV_TIMEOUT))
153		return;
154
155	len = sizeof(sun);
156	if ((connfd = accept(listenfd,
157	    (struct sockaddr *)&sun, &len)) == -1) {
158		/*
159		 * Pause accept if we are out of file descriptors, or
160		 * libevent will haunt us here too.
161		 */
162		if (errno == ENFILE || errno == EMFILE) {
163			struct timeval evtpause = { 1, 0 };
164
165			event_del(&cs->cs_ev);
166			evtimer_add(&cs->cs_evt, &evtpause);
167		} else if (errno != EWOULDBLOCK && errno != EINTR &&
168		    errno != ECONNABORTED)
169			log_warn("%s: accept", __func__);
170		return;
171	}
172
173	socket_set_blockmode(connfd, BM_NONBLOCK);
174
175	if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {
176		log_warn("%s", __func__);
177		close(connfd);
178		return;
179	}
180
181	imsg_init(&c->iev.ibuf, connfd);
182	c->iev.handler = control_dispatch_imsg;
183	c->iev.events = EV_READ;
184	c->iev.data = cs;
185	event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events,
186	    c->iev.handler, c->iev.data);
187	event_add(&c->iev.ev, NULL);
188
189	TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
190}
191
192struct ctl_conn *
193control_connbyfd(int fd)
194{
195	struct ctl_conn	*c;
196
197	for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.fd != fd;
198	    c = TAILQ_NEXT(c, entry))
199		;	/* nothing */
200
201	return (c);
202}
203
204void
205control_close(int fd, struct control_sock *cs)
206{
207	struct ctl_conn	*c;
208
209	if ((c = control_connbyfd(fd)) == NULL) {
210		log_warn("%s: fd %d: not found", __func__, fd);
211		return;
212	}
213
214	msgbuf_clear(&c->iev.ibuf.w);
215	TAILQ_REMOVE(&ctl_conns, c, entry);
216
217	event_del(&c->iev.ev);
218	close(c->iev.ibuf.fd);
219
220	/* Some file descriptors are available again. */
221	if (evtimer_pending(&cs->cs_evt, NULL)) {
222		evtimer_del(&cs->cs_evt);
223		event_add(&cs->cs_ev, NULL);
224	}
225
226	free(c);
227}
228
229/* ARGSUSED */
230void
231control_dispatch_imsg(int fd, short event, void *arg)
232{
233	struct control_sock	*cs = arg;
234	struct iked		*env = cs->cs_env;
235	struct ctl_conn		*c;
236	struct imsg		 imsg;
237	int			 n, v;
238
239	if ((c = control_connbyfd(fd)) == NULL) {
240		log_warn("%s: fd %d: not found", __func__, fd);
241		return;
242	}
243
244	switch (event) {
245	case EV_READ:
246		if ((n = imsg_read(&c->iev.ibuf)) == -1 || n == 0) {
247			control_close(fd, cs);
248			return;
249		}
250		break;
251	case EV_WRITE:
252		if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) {
253			control_close(fd, cs);
254			return;
255		}
256		imsg_event_add(&c->iev);
257		return;
258	default:
259		fatalx("unknown event");
260	}
261
262	for (;;) {
263		if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
264			control_close(fd, cs);
265			return;
266		}
267
268		if (n == 0)
269			break;
270
271		control_imsg_forward(&imsg);
272
273		switch (imsg.hdr.type) {
274		case IMSG_CTL_NOTIFY:
275			if (c->flags & CTL_CONN_NOTIFY) {
276				log_debug("%s: "
277				    "client requested notify more than once",
278				    __func__);
279				imsg_compose_event(&c->iev, IMSG_CTL_FAIL,
280				    0, 0, -1, NULL, 0);
281				break;
282			}
283			c->flags |= CTL_CONN_NOTIFY;
284			break;
285		case IMSG_CTL_VERBOSE:
286			IMSG_SIZE_CHECK(&imsg, &v);
287
288			memcpy(&v, imsg.data, sizeof(v));
289			log_verbose(v);
290
291			proc_forward_imsg(&env->sc_ps, &imsg, PROC_PARENT, -1);
292			proc_forward_imsg(&env->sc_ps, &imsg, PROC_IKEV2, -1);
293			proc_forward_imsg(&env->sc_ps, &imsg, PROC_IKEV1, -1);
294			break;
295		case IMSG_CTL_RELOAD:
296		case IMSG_CTL_RESET:
297		case IMSG_CTL_COUPLE:
298		case IMSG_CTL_DECOUPLE:
299		case IMSG_CTL_ACTIVE:
300		case IMSG_CTL_PASSIVE:
301			proc_forward_imsg(&env->sc_ps, &imsg, PROC_PARENT, -1);
302			break;
303		default:
304			log_debug("%s: error handling imsg %d",
305			    __func__, imsg.hdr.type);
306			break;
307		}
308		imsg_free(&imsg);
309	}
310
311	imsg_event_add(&c->iev);
312}
313
314void
315control_imsg_forward(struct imsg *imsg)
316{
317	struct ctl_conn *c;
318
319	TAILQ_FOREACH(c, &ctl_conns, entry)
320		if (c->flags & CTL_CONN_NOTIFY)
321			imsg_compose(&c->iev.ibuf, imsg->hdr.type,
322			    0, imsg->hdr.pid, -1, imsg->data,
323			    imsg->hdr.len - IMSG_HEADER_SIZE);
324}
325