xref: /openbsd/usr.sbin/ldapd/control.c (revision 771fbea0)
1 /*	$OpenBSD: control.c,v 1.17 2021/04/20 21:11:56 dv Exp $	*/
2 
3 /*
4  * Copyright (c) 2010 Martin Hedenfalk <martin@bzero.se>
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/types.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 <signal.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <unistd.h>
36 
37 #include "ldapd.h"
38 #include "log.h"
39 
40 #define	CONTROL_BACKLOG	5
41 
42 struct ctl_connlist ctl_conns = TAILQ_HEAD_INITIALIZER(ctl_conns);
43 
44 struct ctl_conn	*control_connbyfd(int);
45 void		 control_close(int, struct control_sock *);
46 static void	 control_imsgev(struct imsgev *iev, int code, struct imsg *imsg);
47 static void	 control_needfd(struct imsgev *iev);
48 
49 void
50 control_init(struct control_sock *cs)
51 {
52 	struct sockaddr_un	 sun;
53 	int			 fd;
54 	mode_t			 old_umask, mode;
55 
56 	if (cs->cs_name == NULL)
57 		return;
58 
59 	if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, 0)) == -1)
60 		fatal("control_init: socket");
61 
62 	memset(&sun, 0, sizeof(sun));
63 	sun.sun_family = AF_UNIX;
64 	if (strlcpy(sun.sun_path, cs->cs_name,
65 	    sizeof(sun.sun_path)) >= sizeof(sun.sun_path))
66 		fatalx("control_init: name too long");
67 
68 	if (connect(fd, (struct sockaddr *)&sun, sizeof(sun)) == 0)
69 		fatalx("control socket already listening");
70 
71 	if (unlink(cs->cs_name) == -1 && errno != ENOENT)
72 		fatal("control_init: unlink");
73 
74 	if (cs->cs_restricted) {
75 		old_umask = umask(S_IXUSR|S_IXGRP|S_IXOTH);
76 		mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH;
77 	} else {
78 		old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
79 		mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP;
80 	}
81 
82 	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
83 		(void)umask(old_umask);
84 		fatal("control_init: bind");
85 	}
86 	(void)umask(old_umask);
87 
88 	if (chmod(cs->cs_name, mode) == -1) {
89 		(void)unlink(cs->cs_name);
90 		fatal("control_init: chmod");
91 	}
92 
93 	cs->cs_fd = fd;
94 }
95 
96 void
97 control_listen(struct control_sock *cs)
98 {
99 	if (cs->cs_name == NULL)
100 		return;
101 
102 	if (listen(cs->cs_fd, CONTROL_BACKLOG) == -1)
103 		fatal("control_listen: listen");
104 
105 	event_set(&cs->cs_ev, cs->cs_fd, EV_READ,
106 	    control_accept, cs);
107 	event_add(&cs->cs_ev, NULL);
108 	evtimer_set(&cs->cs_evt, control_accept, cs);
109 }
110 
111 void
112 control_cleanup(struct control_sock *cs)
113 {
114 	if (cs->cs_name == NULL)
115 		return;
116 	event_del(&cs->cs_ev);
117 	event_del(&cs->cs_evt);
118 }
119 
120 /* ARGSUSED */
121 void
122 control_accept(int listenfd, short event, void *arg)
123 {
124 	struct control_sock	*cs = arg;
125 	int			 connfd;
126 	socklen_t		 len;
127 	struct sockaddr_un	 sun;
128 	struct ctl_conn		*c;
129 
130 	event_add(&cs->cs_ev, NULL);
131 	if ((event & EV_TIMEOUT))
132 		return;
133 
134 	len = sizeof(sun);
135 	if ((connfd = accept_reserve(listenfd,
136 	    (struct sockaddr *)&sun, &len, FD_RESERVE)) == -1) {
137 		/*
138 		 * Pause accept if we are out of file descriptors, or
139 		 * libevent will haunt us here too.
140 		 */
141 		if (errno == ENFILE || errno == EMFILE) {
142 			struct timeval evtpause = { 1, 0 };
143 
144 			event_del(&cs->cs_ev);
145 			evtimer_add(&cs->cs_evt, &evtpause);
146 		} else if (errno != EWOULDBLOCK && errno != EINTR)
147 			log_warn("control_accept");
148 		return;
149 	}
150 
151 	if ((c = calloc(1, sizeof(*c))) == NULL) {
152 		log_warn("control_accept");
153 		close(connfd);
154 		return;
155 	}
156 
157 	log_debug("accepted control fd %d", connfd);
158 	TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
159 	imsgev_init(&c->iev, connfd, cs, control_imsgev, control_needfd);
160 }
161 
162 struct ctl_conn *
163 control_connbyfd(int fd)
164 {
165 	struct ctl_conn	*c;
166 
167 	TAILQ_FOREACH(c, &ctl_conns, entry) {
168 		if (c->iev.ibuf.fd == fd)
169 			break;
170 	}
171 
172 	return (c);
173 }
174 
175 void
176 control_close(int fd, struct control_sock *cs)
177 {
178 	struct ctl_conn	*c;
179 
180 	if ((c = control_connbyfd(fd)) == NULL) {
181 		log_warnx("control_close: fd %d: not found", fd);
182 		return;
183 	}
184 
185 	log_debug("close control fd %d", c->iev.ibuf.fd);
186 	TAILQ_REMOVE(&ctl_conns, c, entry);
187 	imsgev_clear(&c->iev);
188 
189 	/* Some file descriptors are available again. */
190 	if (evtimer_pending(&cs->cs_evt, NULL)) {
191 		evtimer_del(&cs->cs_evt);
192 		event_add(&cs->cs_ev, NULL);
193 	}
194 
195 	free(c);
196 }
197 
198 static int
199 send_stats(struct imsgev *iev)
200 {
201 	struct namespace	*ns;
202 	const struct btree_stat	*st;
203 	struct ns_stat		 nss;
204 
205 	imsgev_compose(iev, IMSG_CTL_STATS, 0, iev->ibuf.pid, -1,
206 	    &stats, sizeof(stats));
207 
208 	TAILQ_FOREACH(ns, &conf->namespaces, next) {
209 		if (namespace_has_referrals(ns))
210 			continue;
211 		memset(&nss, 0, sizeof(nss));
212 		strlcpy(nss.suffix, ns->suffix, sizeof(nss.suffix));
213 		if ((st = btree_stat(ns->data_db)) != NULL)
214 			bcopy(st, &nss.data_stat, sizeof(nss.data_stat));
215 
216 		if ((st = btree_stat(ns->indx_db)) != NULL)
217 			bcopy(st, &nss.indx_stat, sizeof(nss.indx_stat));
218 
219 		imsgev_compose(iev, IMSG_CTL_NSSTATS, 0, iev->ibuf.pid, -1,
220 		    &nss, sizeof(nss));
221 	}
222 
223 	imsgev_compose(iev, IMSG_CTL_END, 0, iev->ibuf.pid, -1, NULL, 0);
224 
225 	return 0;
226 }
227 
228 static void
229 control_imsgev(struct imsgev *iev, int code, struct imsg *imsg)
230 {
231 	struct control_sock	*cs;
232 	struct ctl_conn		*c;
233 	int			 fd, verbose;
234 
235 	cs = iev->data;
236 	fd = iev->ibuf.fd;
237 
238 	if ((c = control_connbyfd(fd)) == NULL) {
239 		log_warnx("%s: fd %d: not found", __func__, fd);
240 		return;
241 	}
242 
243 	if (code != IMSGEV_IMSG) {
244 		control_close(fd, cs);
245 		return;
246 	}
247 
248 	log_debug("%s: got imsg %d on fd %d", __func__, imsg->hdr.type, fd);
249 	switch (imsg->hdr.type) {
250 	case IMSG_CTL_STATS:
251 		if (send_stats(iev) == -1) {
252 			log_debug("%s: failed to send statistics", __func__);
253 			control_close(fd, cs);
254 		}
255 		break;
256 	case IMSG_CTL_LOG_VERBOSE:
257 		if (imsg->hdr.len != IMSG_HEADER_SIZE + sizeof(verbose))
258 			break;
259 
260 		bcopy(imsg->data, &verbose, sizeof(verbose));
261 		imsgev_compose(iev_ldapd, IMSG_CTL_LOG_VERBOSE, 0, 0, -1,
262 		    &verbose, sizeof(verbose));
263 
264 		log_setverbose(verbose);
265 		break;
266 	default:
267 		log_warnx("%s: unexpected imsg %d", __func__, imsg->hdr.type);
268 		break;
269 	}
270 }
271 
272 void
273 control_needfd(struct imsgev *iev)
274 {
275 	fatal("should never need an fd for control messages");
276 }
277 
278 int
279 control_close_any(struct control_sock *cs)
280 {
281 	struct ctl_conn		*c;
282 
283 	c = TAILQ_FIRST(&ctl_conns);
284 	if (c != NULL) {
285 		log_warn("closing oldest control connection");
286 		control_close(c->iev.ibuf.fd, cs);
287 		return (0);
288 	}
289 	log_warn("no control connections to close");
290 	return (-1);
291 }
292