control.c revision 1.17 
1/*	$OpenBSD: control.c,v 1.17 2015/10/19 11:25:35 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/stat.h>
22#include <sys/socket.h>
23#include <sys/un.h>
24#include <sys/tree.h>
25
26#include <net/if.h>
27
28#include <errno.h>
29#include <event.h>
30#include <fcntl.h>
31#include <stdlib.h>
32#include <string.h>
33#include <unistd.h>
34#include <signal.h>
35
36#include "iked.h"
37
38#define	CONTROL_BACKLOG	5
39
40struct ctl_connlist ctl_conns;
41
42void
43	 control_accept(int, short, void *);
44struct ctl_conn
45	*control_connbyfd(int);
46void	 control_close(int, struct control_sock *);
47void	 control_dispatch_imsg(int, short, void *);
48void	 control_imsg_forward(struct imsg *);
49
50int
51control_init(struct privsep *ps, struct control_sock *cs)
52{
53	struct iked		*env = ps->ps_env;
54	struct sockaddr_un	 sun;
55	int			 fd;
56	mode_t			 old_umask, mode;
57
58	if (cs->cs_name == NULL)
59		return (0);
60
61	if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
62		log_warn("%s: socket", __func__);
63		return (-1);
64	}
65
66	sun.sun_family = AF_UNIX;
67	if (strlcpy(sun.sun_path, cs->cs_name,
68	    sizeof(sun.sun_path)) >= sizeof(sun.sun_path)) {
69		log_warn("%s: %s name too long", __func__, cs->cs_name);
70		close(fd);
71		return (-1);
72	}
73
74	if (unlink(cs->cs_name) == -1)
75		if (errno != ENOENT) {
76			log_warn("%s: unlink %s", __func__, cs->cs_name);
77			close(fd);
78			return (-1);
79		}
80
81	if (cs->cs_restricted) {
82		old_umask = umask(S_IXUSR|S_IXGRP|S_IXOTH);
83		mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH;
84	} else {
85		old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
86		mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP;
87	}
88
89	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
90		log_warn("%s: bind: %s", __func__, cs->cs_name);
91		close(fd);
92		(void)umask(old_umask);
93		return (-1);
94	}
95	(void)umask(old_umask);
96
97	if (chmod(cs->cs_name, mode) == -1) {
98		log_warn("%s: chmod", __func__);
99		close(fd);
100		(void)unlink(cs->cs_name);
101		return (-1);
102	}
103
104	socket_set_blockmode(fd, BM_NONBLOCK);
105	cs->cs_fd = fd;
106	cs->cs_env = env;
107
108	return (0);
109}
110
111int
112control_listen(struct control_sock *cs)
113{
114	if (cs->cs_name == NULL)
115		return (0);
116
117	if (listen(cs->cs_fd, CONTROL_BACKLOG) == -1) {
118		log_warn("%s: listen", __func__);
119		return (-1);
120	}
121
122	event_set(&cs->cs_ev, cs->cs_fd, EV_READ,
123	    control_accept, cs);
124	event_add(&cs->cs_ev, NULL);
125	evtimer_set(&cs->cs_evt, control_accept, cs);
126
127	return (0);
128}
129
130void
131control_cleanup(struct control_sock *cs)
132{
133	if (cs->cs_name == NULL)
134		return;
135	event_del(&cs->cs_ev);
136	event_del(&cs->cs_evt);
137	(void)unlink(cs->cs_name);
138}
139
140/* ARGSUSED */
141void
142control_accept(int listenfd, short event, void *arg)
143{
144	struct control_sock	*cs = arg;
145	int			 connfd;
146	socklen_t		 len;
147	struct sockaddr_un	 sun;
148	struct ctl_conn		*c;
149
150	event_add(&cs->cs_ev, NULL);
151	if ((event & EV_TIMEOUT))
152		return;
153
154	len = sizeof(sun);
155	if ((connfd = accept(listenfd,
156	    (struct sockaddr *)&sun, &len)) == -1) {
157		/*
158		 * Pause accept if we are out of file descriptors, or
159		 * libevent will haunt us here too.
160		 */
161		if (errno == ENFILE || errno == EMFILE) {
162			struct timeval evtpause = { 1, 0 };
163
164			event_del(&cs->cs_ev);
165			evtimer_add(&cs->cs_evt, &evtpause);
166		} else if (errno != EWOULDBLOCK && errno != EINTR &&
167		    errno != ECONNABORTED)
168			log_warn("%s: accept", __func__);
169		return;
170	}
171
172	socket_set_blockmode(connfd, BM_NONBLOCK);
173
174	if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {
175		log_warn("%s", __func__);
176		close(connfd);
177		return;
178	}
179
180	imsg_init(&c->iev.ibuf, connfd);
181	c->iev.handler = control_dispatch_imsg;
182	c->iev.events = EV_READ;
183	c->iev.data = cs;
184	event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events,
185	    c->iev.handler, c->iev.data);
186	event_add(&c->iev.ev, NULL);
187
188	TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
189}
190
191struct ctl_conn *
192control_connbyfd(int fd)
193{
194	struct ctl_conn	*c;
195
196	for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.fd != fd;
197	    c = TAILQ_NEXT(c, entry))
198		;	/* nothing */
199
200	return (c);
201}
202
203void
204control_close(int fd, struct control_sock *cs)
205{
206	struct ctl_conn	*c;
207
208	if ((c = control_connbyfd(fd)) == NULL) {
209		log_warn("%s: fd %d: not found", __func__, fd);
210		return;
211	}
212
213	msgbuf_clear(&c->iev.ibuf.w);
214	TAILQ_REMOVE(&ctl_conns, c, entry);
215
216	event_del(&c->iev.ev);
217	close(c->iev.ibuf.fd);
218
219	/* Some file descriptors are available again. */
220	if (evtimer_pending(&cs->cs_evt, NULL)) {
221		evtimer_del(&cs->cs_evt);
222		event_add(&cs->cs_ev, NULL);
223	}
224
225	free(c);
226}
227
228/* ARGSUSED */
229void
230control_dispatch_imsg(int fd, short event, void *arg)
231{
232	struct control_sock	*cs = arg;
233	struct iked		*env = cs->cs_env;
234	struct ctl_conn		*c;
235	struct imsg		 imsg;
236	int			 n, v;
237
238	if ((c = control_connbyfd(fd)) == NULL) {
239		log_warn("%s: fd %d: not found", __func__, fd);
240		return;
241	}
242
243	if (event & EV_READ) {
244		if ((n = imsg_read(&c->iev.ibuf)) == -1 || n == 0) {
245			control_close(fd, cs);
246			return;
247		}
248	}
249	if (event & EV_WRITE) {
250		if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) {
251			control_close(fd, cs);
252			return;
253		}
254	}
255
256	for (;;) {
257		if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
258			control_close(fd, cs);
259			return;
260		}
261
262		if (n == 0)
263			break;
264
265		control_imsg_forward(&imsg);
266
267		switch (imsg.hdr.type) {
268		case IMSG_CTL_NOTIFY:
269			if (c->flags & CTL_CONN_NOTIFY) {
270				log_debug("%s: "
271				    "client requested notify more than once",
272				    __func__);
273				imsg_compose_event(&c->iev, IMSG_CTL_FAIL,
274				    0, 0, -1, NULL, 0);
275				break;
276			}
277			c->flags |= CTL_CONN_NOTIFY;
278			break;
279		case IMSG_CTL_VERBOSE:
280			IMSG_SIZE_CHECK(&imsg, &v);
281
282			memcpy(&v, imsg.data, sizeof(v));
283			log_verbose(v);
284
285			proc_forward_imsg(&env->sc_ps, &imsg, PROC_PARENT, -1);
286			proc_forward_imsg(&env->sc_ps, &imsg, PROC_IKEV2, -1);
287			break;
288		case IMSG_CTL_RELOAD:
289		case IMSG_CTL_RESET:
290		case IMSG_CTL_COUPLE:
291		case IMSG_CTL_DECOUPLE:
292		case IMSG_CTL_ACTIVE:
293		case IMSG_CTL_PASSIVE:
294			proc_forward_imsg(&env->sc_ps, &imsg, PROC_PARENT, -1);
295			break;
296		default:
297			log_debug("%s: error handling imsg %d",
298			    __func__, imsg.hdr.type);
299			break;
300		}
301		imsg_free(&imsg);
302	}
303
304	imsg_event_add(&c->iev);
305}
306
307void
308control_imsg_forward(struct imsg *imsg)
309{
310	struct ctl_conn *c;
311
312	TAILQ_FOREACH(c, &ctl_conns, entry)
313		if (c->flags & CTL_CONN_NOTIFY)
314			imsg_compose(&c->iev.ibuf, imsg->hdr.type,
315			    0, imsg->hdr.pid, -1, imsg->data,
316			    imsg->hdr.len - IMSG_HEADER_SIZE);
317}
318