1 8d1b399b 2021-07-22 op /*
  2 8d1b399b 2021-07-22 op  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
  3 8d1b399b 2021-07-22 op  *
  4 8d1b399b 2021-07-22 op  * Permission to use, copy, modify, and distribute this software for any
  5 8d1b399b 2021-07-22 op  * purpose with or without fee is hereby granted, provided that the above
  6 8d1b399b 2021-07-22 op  * copyright notice and this permission notice appear in all copies.
  7 8d1b399b 2021-07-22 op  *
  8 8d1b399b 2021-07-22 op  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  9 8d1b399b 2021-07-22 op  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 10 8d1b399b 2021-07-22 op  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 11 8d1b399b 2021-07-22 op  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 12 8d1b399b 2021-07-22 op  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 13 8d1b399b 2021-07-22 op  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 14 8d1b399b 2021-07-22 op  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 15 8d1b399b 2021-07-22 op  */
 16 8d1b399b 2021-07-22 op 
 17 dc25b034 2021-07-22 op #include "compat.h"
 18 dc25b034 2021-07-22 op 
 19 8d1b399b 2021-07-22 op #include <sys/types.h>
 20 8d1b399b 2021-07-22 op #include <sys/stat.h>
 21 8d1b399b 2021-07-22 op #include <sys/socket.h>
 22 8d1b399b 2021-07-22 op #include <sys/uio.h>
 23 8d1b399b 2021-07-22 op #include <sys/un.h>
 24 8d1b399b 2021-07-22 op 
 25 8d1b399b 2021-07-22 op #include <netinet/in.h>
 26 8d1b399b 2021-07-22 op #include <net/if.h>
 27 8d1b399b 2021-07-22 op 
 28 8d1b399b 2021-07-22 op #include <errno.h>
 29 8d1b399b 2021-07-22 op #include <stdlib.h>
 30 8d1b399b 2021-07-22 op #include <string.h>
 31 8d1b399b 2021-07-22 op #include <unistd.h>
 32 8d1b399b 2021-07-22 op 
 33 8d1b399b 2021-07-22 op #include "log.h"
 34 8d1b399b 2021-07-22 op #include "kamid.h"
 35 8d1b399b 2021-07-22 op #include "control.h"
 36 8d1b399b 2021-07-22 op #include "listener.h"
 37 8d1b399b 2021-07-22 op 
 38 8d1b399b 2021-07-22 op #define	CONTROL_BACKLOG	5
 39 8d1b399b 2021-07-22 op 
 40 8d1b399b 2021-07-22 op struct {
 41 8d1b399b 2021-07-22 op 	struct event	ev;
 42 8d1b399b 2021-07-22 op 	struct event	evt;
 43 8d1b399b 2021-07-22 op 	int		fd;
 44 8d1b399b 2021-07-22 op } control_state = {.fd = -1};
 45 8d1b399b 2021-07-22 op 
 46 8d1b399b 2021-07-22 op struct ctl_conn {
 47 8d1b399b 2021-07-22 op 	TAILQ_ENTRY(ctl_conn)	entry;
 48 8d1b399b 2021-07-22 op 	struct imsgev		iev;
 49 8d1b399b 2021-07-22 op };
 50 8d1b399b 2021-07-22 op 
 51 8d1b399b 2021-07-22 op TAILQ_HEAD(ctl_conns, ctl_conn)	ctl_conns = TAILQ_HEAD_INITIALIZER(ctl_conns);
 52 8d1b399b 2021-07-22 op 
 53 8d1b399b 2021-07-22 op struct ctl_conn	*control_connbyfd(int);
 54 8d1b399b 2021-07-22 op struct ctl_conn	*control_connbypid(pid_t);
 55 8d1b399b 2021-07-22 op void		 control_close(int);
 56 8d1b399b 2021-07-22 op 
 57 8d1b399b 2021-07-22 op int
 58 8d1b399b 2021-07-22 op control_init(const char *path)
 59 8d1b399b 2021-07-22 op {
 60 8d1b399b 2021-07-22 op 	struct sockaddr_un	 sun;
 61 8d1b399b 2021-07-22 op 	int			 fd;
 62 8d1b399b 2021-07-22 op 	mode_t			 old_umask;
 63 8d1b399b 2021-07-22 op 
 64 8d1b399b 2021-07-22 op 	if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
 65 8d1b399b 2021-07-22 op 	    0)) == -1) {
 66 8d1b399b 2021-07-22 op 		log_warn("%s: socket", __func__);
 67 8d1b399b 2021-07-22 op 		return (-1);
 68 8d1b399b 2021-07-22 op 	}
 69 8d1b399b 2021-07-22 op 
 70 8d1b399b 2021-07-22 op 	memset(&sun, 0, sizeof(sun));
 71 8d1b399b 2021-07-22 op 	sun.sun_family = AF_UNIX;
 72 8d1b399b 2021-07-22 op 	strlcpy(sun.sun_path, path, sizeof(sun.sun_path));
 73 8d1b399b 2021-07-22 op 
 74 8d1b399b 2021-07-22 op 	if (unlink(path) == -1)
 75 8d1b399b 2021-07-22 op 		if (errno != ENOENT) {
 76 8d1b399b 2021-07-22 op 			log_warn("%s: unlink %s", __func__, path);
 77 8d1b399b 2021-07-22 op 			close(fd);
 78 8d1b399b 2021-07-22 op 			return (-1);
 79 8d1b399b 2021-07-22 op 		}
 80 8d1b399b 2021-07-22 op 
 81 8d1b399b 2021-07-22 op 	old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
 82 8d1b399b 2021-07-22 op 	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
 83 8d1b399b 2021-07-22 op 		log_warn("%s: bind: %s", __func__, path);
 84 8d1b399b 2021-07-22 op 		close(fd);
 85 8d1b399b 2021-07-22 op 		umask(old_umask);
 86 8d1b399b 2021-07-22 op 		return (-1);
 87 8d1b399b 2021-07-22 op 	}
 88 8d1b399b 2021-07-22 op 	umask(old_umask);
 89 8d1b399b 2021-07-22 op 
 90 8d1b399b 2021-07-22 op 	if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {
 91 8d1b399b 2021-07-22 op 		log_warn("%s: chmod", __func__);
 92 8d1b399b 2021-07-22 op 		close(fd);
 93 8d1b399b 2021-07-22 op 		(void)unlink(path);
 94 8d1b399b 2021-07-22 op 		return (-1);
 95 8d1b399b 2021-07-22 op 	}
 96 8d1b399b 2021-07-22 op 
 97 8d1b399b 2021-07-22 op 	return (fd);
 98 8d1b399b 2021-07-22 op }
 99 8d1b399b 2021-07-22 op 
100 8d1b399b 2021-07-22 op int
101 8d1b399b 2021-07-22 op control_listen(int fd)
102 8d1b399b 2021-07-22 op {
103 8d1b399b 2021-07-22 op 	if (control_state.fd != -1)
104 8d1b399b 2021-07-22 op 		fatalx("%s: received unexpected controlsock", __func__);
105 8d1b399b 2021-07-22 op 
106 8d1b399b 2021-07-22 op 	control_state.fd = fd;
107 8d1b399b 2021-07-22 op 	if (listen(control_state.fd, CONTROL_BACKLOG) == -1) {
108 8d1b399b 2021-07-22 op 		log_warn("%s: listen", __func__);
109 8d1b399b 2021-07-22 op 		return (-1);
110 8d1b399b 2021-07-22 op 	}
111 8d1b399b 2021-07-22 op 
112 8d1b399b 2021-07-22 op 	event_set(&control_state.ev, control_state.fd, EV_READ,
113 8d1b399b 2021-07-22 op 	    control_accept, NULL);
114 8d1b399b 2021-07-22 op 	event_add(&control_state.ev, NULL);
115 8d1b399b 2021-07-22 op 	evtimer_set(&control_state.evt, control_accept, NULL);
116 8d1b399b 2021-07-22 op 
117 8d1b399b 2021-07-22 op 	return (0);
118 8d1b399b 2021-07-22 op }
119 8d1b399b 2021-07-22 op 
120 8d1b399b 2021-07-22 op void
121 8d1b399b 2021-07-22 op control_accept(int listenfd, short event, void *bula)
122 8d1b399b 2021-07-22 op {
123 8d1b399b 2021-07-22 op 	int			 connfd;
124 8d1b399b 2021-07-22 op 	socklen_t		 len;
125 8d1b399b 2021-07-22 op 	struct sockaddr_un	 sun;
126 8d1b399b 2021-07-22 op 	struct ctl_conn		*c;
127 8d1b399b 2021-07-22 op 
128 8d1b399b 2021-07-22 op 	event_add(&control_state.ev, NULL);
129 8d1b399b 2021-07-22 op 	if ((event & EV_TIMEOUT))
130 8d1b399b 2021-07-22 op 		return;
131 8d1b399b 2021-07-22 op 
132 8d1b399b 2021-07-22 op 	len = sizeof(sun);
133 8d1b399b 2021-07-22 op 	if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len,
134 8d1b399b 2021-07-22 op 	    SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) {
135 8d1b399b 2021-07-22 op 		/*
136 8d1b399b 2021-07-22 op 		 * Pause accept if we are out of file descriptors, or
137 8d1b399b 2021-07-22 op 		 * libevent will haunt us here too.
138 8d1b399b 2021-07-22 op 		 */
139 8d1b399b 2021-07-22 op 		if (errno == ENFILE || errno == EMFILE) {
140 8d1b399b 2021-07-22 op 			struct timeval evtpause = { 1, 0 };
141 8d1b399b 2021-07-22 op 
142 8d1b399b 2021-07-22 op 			event_del(&control_state.ev);
143 8d1b399b 2021-07-22 op 			evtimer_add(&control_state.evt, &evtpause);
144 8d1b399b 2021-07-22 op 		} else if (errno != EWOULDBLOCK && errno != EINTR &&
145 8d1b399b 2021-07-22 op 		    errno != ECONNABORTED)
146 8d1b399b 2021-07-22 op 			log_warn("%s: accept4", __func__);
147 8d1b399b 2021-07-22 op 		return;
148 8d1b399b 2021-07-22 op 	}
149 8d1b399b 2021-07-22 op 
150 8d1b399b 2021-07-22 op 	if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {
151 8d1b399b 2021-07-22 op 		log_warn("%s: calloc", __func__);
152 8d1b399b 2021-07-22 op 		close(connfd);
153 8d1b399b 2021-07-22 op 		return;
154 8d1b399b 2021-07-22 op 	}
155 8d1b399b 2021-07-22 op 
156 8d1b399b 2021-07-22 op 	imsg_init(&c->iev.ibuf, connfd);
157 8d1b399b 2021-07-22 op 	c->iev.handler = control_dispatch_imsg;
158 8d1b399b 2021-07-22 op 	c->iev.events = EV_READ;
159 8d1b399b 2021-07-22 op 	event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events,
160 8d1b399b 2021-07-22 op 	    c->iev.handler, &c->iev);
161 8d1b399b 2021-07-22 op 	event_add(&c->iev.ev, NULL);
162 8d1b399b 2021-07-22 op 
163 8d1b399b 2021-07-22 op 	TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
164 8d1b399b 2021-07-22 op }
165 8d1b399b 2021-07-22 op 
166 8d1b399b 2021-07-22 op struct ctl_conn *
167 8d1b399b 2021-07-22 op control_connbyfd(int fd)
168 8d1b399b 2021-07-22 op {
169 8d1b399b 2021-07-22 op 	struct ctl_conn	*c;
170 8d1b399b 2021-07-22 op 
171 8d1b399b 2021-07-22 op 	TAILQ_FOREACH(c, &ctl_conns, entry) {
172 8d1b399b 2021-07-22 op 		if (c->iev.ibuf.fd == fd)
173 8d1b399b 2021-07-22 op 			break;
174 8d1b399b 2021-07-22 op 	}
175 8d1b399b 2021-07-22 op 
176 8d1b399b 2021-07-22 op 	return (c);
177 8d1b399b 2021-07-22 op }
178 8d1b399b 2021-07-22 op 
179 8d1b399b 2021-07-22 op struct ctl_conn *
180 8d1b399b 2021-07-22 op control_connbypid(pid_t pid)
181 8d1b399b 2021-07-22 op {
182 8d1b399b 2021-07-22 op 	struct ctl_conn	*c;
183 8d1b399b 2021-07-22 op 
184 8d1b399b 2021-07-22 op 	TAILQ_FOREACH(c, &ctl_conns, entry) {
185 8d1b399b 2021-07-22 op 		if (c->iev.ibuf.pid == pid)
186 8d1b399b 2021-07-22 op 			break;
187 8d1b399b 2021-07-22 op 	}
188 8d1b399b 2021-07-22 op 
189 8d1b399b 2021-07-22 op 	return (c);
190 8d1b399b 2021-07-22 op }
191 8d1b399b 2021-07-22 op 
192 8d1b399b 2021-07-22 op void
193 8d1b399b 2021-07-22 op control_close(int fd)
194 8d1b399b 2021-07-22 op {
195 8d1b399b 2021-07-22 op 	struct ctl_conn	*c;
196 8d1b399b 2021-07-22 op 
197 8d1b399b 2021-07-22 op 	if ((c = control_connbyfd(fd)) == NULL) {
198 8d1b399b 2021-07-22 op 		log_warnx("%s: fd %d: not found", __func__, fd);
199 8d1b399b 2021-07-22 op 		return;
200 8d1b399b 2021-07-22 op 	}
201 8d1b399b 2021-07-22 op 
202 8d1b399b 2021-07-22 op 	msgbuf_clear(&c->iev.ibuf.w);
203 8d1b399b 2021-07-22 op 	TAILQ_REMOVE(&ctl_conns, c, entry);
204 8d1b399b 2021-07-22 op 
205 8d1b399b 2021-07-22 op 	event_del(&c->iev.ev);
206 8d1b399b 2021-07-22 op 	close(c->iev.ibuf.fd);
207 8d1b399b 2021-07-22 op 
208 8d1b399b 2021-07-22 op 	/* Some file descriptors are available again. */
209 8d1b399b 2021-07-22 op 	if (evtimer_pending(&control_state.evt, NULL)) {
210 8d1b399b 2021-07-22 op 		evtimer_del(&control_state.evt);
211 8d1b399b 2021-07-22 op 		event_add(&control_state.ev, NULL);
212 8d1b399b 2021-07-22 op 	}
213 8d1b399b 2021-07-22 op 
214 8d1b399b 2021-07-22 op 	free(c);
215 8d1b399b 2021-07-22 op }
216 8d1b399b 2021-07-22 op 
217 8d1b399b 2021-07-22 op void
218 8d1b399b 2021-07-22 op control_dispatch_imsg(int fd, short event, void *bula)
219 8d1b399b 2021-07-22 op {
220 8d1b399b 2021-07-22 op 	struct ctl_conn	*c;
221 8d1b399b 2021-07-22 op 	struct imsg	 imsg;
222 8d1b399b 2021-07-22 op 	ssize_t		 n;
223 8d1b399b 2021-07-22 op 	int		 verbose;
224 8d1b399b 2021-07-22 op 
225 8d1b399b 2021-07-22 op 	if ((c = control_connbyfd(fd)) == NULL) {
226 8d1b399b 2021-07-22 op 		log_warnx("%s: fd %d: not found", __func__, fd);
227 8d1b399b 2021-07-22 op 		return;
228 8d1b399b 2021-07-22 op 	}
229 8d1b399b 2021-07-22 op 
230 8d1b399b 2021-07-22 op 	if (event & EV_READ) {
231 8d1b399b 2021-07-22 op 		if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) ||
232 8d1b399b 2021-07-22 op 		    n == 0) {
233 8d1b399b 2021-07-22 op 			control_close(fd);
234 8d1b399b 2021-07-22 op 			return;
235 8d1b399b 2021-07-22 op 		}
236 8d1b399b 2021-07-22 op 	}
237 8d1b399b 2021-07-22 op 	if (event & EV_WRITE) {
238 8d1b399b 2021-07-22 op 		if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) {
239 8d1b399b 2021-07-22 op 			control_close(fd);
240 8d1b399b 2021-07-22 op 			return;
241 8d1b399b 2021-07-22 op 		}
242 8d1b399b 2021-07-22 op 	}
243 8d1b399b 2021-07-22 op 
244 8d1b399b 2021-07-22 op 	for (;;) {
245 8d1b399b 2021-07-22 op 		if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
246 8d1b399b 2021-07-22 op 			control_close(fd);
247 8d1b399b 2021-07-22 op 			return;
248 8d1b399b 2021-07-22 op 		}
249 8d1b399b 2021-07-22 op 		if (n == 0)
250 8d1b399b 2021-07-22 op 			break;
251 8d1b399b 2021-07-22 op 
252 8d1b399b 2021-07-22 op 		switch (imsg.hdr.type) {
253 8d1b399b 2021-07-22 op 		case IMSG_CTL_RELOAD:
254 8d1b399b 2021-07-22 op 			listener_imsg_compose_main(imsg.hdr.type, 0, NULL, 0);
255 8d1b399b 2021-07-22 op 			break;
256 8d1b399b 2021-07-22 op 		case IMSG_CTL_LOG_VERBOSE:
257 8d1b399b 2021-07-22 op 			if (IMSG_DATA_SIZE(imsg) != sizeof(verbose))
258 8d1b399b 2021-07-22 op 				break;
259 8d1b399b 2021-07-22 op 
260 8d1b399b 2021-07-22 op 			/* Forward to all other processes. */
261 8d1b399b 2021-07-22 op 			listener_imsg_compose_main(imsg.hdr.type, imsg.hdr.pid,
262 8d1b399b 2021-07-22 op 			    imsg.data, IMSG_DATA_SIZE(imsg));
263 8d1b399b 2021-07-22 op 
264 8d1b399b 2021-07-22 op 			/* XXX: send to every client? */
265 8d1b399b 2021-07-22 op 
266 8d1b399b 2021-07-22 op 			memcpy(&verbose, imsg.data, sizeof(verbose));
267 8d1b399b 2021-07-22 op 			log_setverbose(verbose);
268 8d1b399b 2021-07-22 op 			break;
269 8d1b399b 2021-07-22 op 		default:
270 8d1b399b 2021-07-22 op 			log_debug("%s: error handling imsg %d", __func__,
271 8d1b399b 2021-07-22 op 			    imsg.hdr.type);
272 8d1b399b 2021-07-22 op 			break;
273 8d1b399b 2021-07-22 op 		}
274 8d1b399b 2021-07-22 op 		imsg_free(&imsg);
275 8d1b399b 2021-07-22 op 	}
276 8d1b399b 2021-07-22 op 
277 8d1b399b 2021-07-22 op 	imsg_event_add(&c->iev);
278 8d1b399b 2021-07-22 op }
279 8d1b399b 2021-07-22 op 
280 8d1b399b 2021-07-22 op int
281 8d1b399b 2021-07-22 op control_imsg_relay(struct imsg *imsg)
282 8d1b399b 2021-07-22 op {
283 8d1b399b 2021-07-22 op 	struct ctl_conn	*c;
284 8d1b399b 2021-07-22 op 
285 8d1b399b 2021-07-22 op 	if ((c = control_connbypid(imsg->hdr.pid)) == NULL)
286 8d1b399b 2021-07-22 op 		return (0);
287 8d1b399b 2021-07-22 op 
288 8d1b399b 2021-07-22 op 	return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid,
289 8d1b399b 2021-07-22 op 	    -1, imsg->data, IMSG_DATA_SIZE(*imsg)));
290 8d1b399b 2021-07-22 op }