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