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 "control.h"
 34 9820edbf 2021-08-06 op #include "kamid.h"
 35 8d1b399b 2021-07-22 op #include "listener.h"
 36 9820edbf 2021-08-06 op #include "log.h"
 37 9820edbf 2021-08-06 op #include "utils.h"
 38 8d1b399b 2021-07-22 op 
 39 8d1b399b 2021-07-22 op #define	CONTROL_BACKLOG	5
 40 8d1b399b 2021-07-22 op 
 41 8d1b399b 2021-07-22 op struct {
 42 8d1b399b 2021-07-22 op 	struct event	ev;
 43 8d1b399b 2021-07-22 op 	struct event	evt;
 44 8d1b399b 2021-07-22 op 	int		fd;
 45 8d1b399b 2021-07-22 op } control_state = {.fd = -1};
 46 8d1b399b 2021-07-22 op 
 47 8d1b399b 2021-07-22 op struct ctl_conn {
 48 8d1b399b 2021-07-22 op 	TAILQ_ENTRY(ctl_conn)	entry;
 49 8d1b399b 2021-07-22 op 	struct imsgev		iev;
 50 8d1b399b 2021-07-22 op };
 51 8d1b399b 2021-07-22 op 
 52 8d1b399b 2021-07-22 op TAILQ_HEAD(ctl_conns, ctl_conn)	ctl_conns = TAILQ_HEAD_INITIALIZER(ctl_conns);
 53 8d1b399b 2021-07-22 op 
 54 8d1b399b 2021-07-22 op struct ctl_conn	*control_connbyfd(int);
 55 8d1b399b 2021-07-22 op struct ctl_conn	*control_connbypid(pid_t);
 56 8d1b399b 2021-07-22 op void		 control_close(int);
 57 8d1b399b 2021-07-22 op 
 58 8d1b399b 2021-07-22 op int
 59 8d1b399b 2021-07-22 op control_init(const char *path)
 60 8d1b399b 2021-07-22 op {
 61 8d1b399b 2021-07-22 op 	struct sockaddr_un	 sun;
 62 8d1b399b 2021-07-22 op 	int			 fd;
 63 8d1b399b 2021-07-22 op 	mode_t			 old_umask;
 64 8d1b399b 2021-07-22 op 
 65 8d1b399b 2021-07-22 op 	if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
 66 8d1b399b 2021-07-22 op 	    0)) == -1) {
 67 8d1b399b 2021-07-22 op 		log_warn("%s: socket", __func__);
 68 8d1b399b 2021-07-22 op 		return (-1);
 69 8d1b399b 2021-07-22 op 	}
 70 8d1b399b 2021-07-22 op 
 71 8d1b399b 2021-07-22 op 	memset(&sun, 0, sizeof(sun));
 72 8d1b399b 2021-07-22 op 	sun.sun_family = AF_UNIX;
 73 8d1b399b 2021-07-22 op 	strlcpy(sun.sun_path, path, sizeof(sun.sun_path));
 74 8d1b399b 2021-07-22 op 
 75 8d1b399b 2021-07-22 op 	if (unlink(path) == -1)
 76 8d1b399b 2021-07-22 op 		if (errno != ENOENT) {
 77 8d1b399b 2021-07-22 op 			log_warn("%s: unlink %s", __func__, path);
 78 8d1b399b 2021-07-22 op 			close(fd);
 79 8d1b399b 2021-07-22 op 			return (-1);
 80 8d1b399b 2021-07-22 op 		}
 81 8d1b399b 2021-07-22 op 
 82 8d1b399b 2021-07-22 op 	old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
 83 8d1b399b 2021-07-22 op 	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
 84 8d1b399b 2021-07-22 op 		log_warn("%s: bind: %s", __func__, path);
 85 8d1b399b 2021-07-22 op 		close(fd);
 86 8d1b399b 2021-07-22 op 		umask(old_umask);
 87 8d1b399b 2021-07-22 op 		return (-1);
 88 8d1b399b 2021-07-22 op 	}
 89 8d1b399b 2021-07-22 op 	umask(old_umask);
 90 8d1b399b 2021-07-22 op 
 91 8d1b399b 2021-07-22 op 	if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {
 92 8d1b399b 2021-07-22 op 		log_warn("%s: chmod", __func__);
 93 8d1b399b 2021-07-22 op 		close(fd);
 94 8d1b399b 2021-07-22 op 		(void)unlink(path);
 95 8d1b399b 2021-07-22 op 		return (-1);
 96 8d1b399b 2021-07-22 op 	}
 97 8d1b399b 2021-07-22 op 
 98 8d1b399b 2021-07-22 op 	return (fd);
 99 8d1b399b 2021-07-22 op }
100 8d1b399b 2021-07-22 op 
101 8d1b399b 2021-07-22 op int
102 8d1b399b 2021-07-22 op control_listen(int fd)
103 8d1b399b 2021-07-22 op {
104 8d1b399b 2021-07-22 op 	if (control_state.fd != -1)
105 8d1b399b 2021-07-22 op 		fatalx("%s: received unexpected controlsock", __func__);
106 8d1b399b 2021-07-22 op 
107 8d1b399b 2021-07-22 op 	control_state.fd = fd;
108 8d1b399b 2021-07-22 op 	if (listen(control_state.fd, CONTROL_BACKLOG) == -1) {
109 8d1b399b 2021-07-22 op 		log_warn("%s: listen", __func__);
110 8d1b399b 2021-07-22 op 		return (-1);
111 8d1b399b 2021-07-22 op 	}
112 8d1b399b 2021-07-22 op 
113 8d1b399b 2021-07-22 op 	event_set(&control_state.ev, control_state.fd, EV_READ,
114 8d1b399b 2021-07-22 op 	    control_accept, NULL);
115 8d1b399b 2021-07-22 op 	event_add(&control_state.ev, NULL);
116 8d1b399b 2021-07-22 op 	evtimer_set(&control_state.evt, control_accept, NULL);
117 8d1b399b 2021-07-22 op 
118 8d1b399b 2021-07-22 op 	return (0);
119 8d1b399b 2021-07-22 op }
120 8d1b399b 2021-07-22 op 
121 8d1b399b 2021-07-22 op void
122 8d1b399b 2021-07-22 op control_accept(int listenfd, short event, void *bula)
123 8d1b399b 2021-07-22 op {
124 8d1b399b 2021-07-22 op 	int			 connfd;
125 8d1b399b 2021-07-22 op 	socklen_t		 len;
126 8d1b399b 2021-07-22 op 	struct sockaddr_un	 sun;
127 8d1b399b 2021-07-22 op 	struct ctl_conn		*c;
128 8d1b399b 2021-07-22 op 
129 8d1b399b 2021-07-22 op 	event_add(&control_state.ev, NULL);
130 8d1b399b 2021-07-22 op 	if ((event & EV_TIMEOUT))
131 8d1b399b 2021-07-22 op 		return;
132 8d1b399b 2021-07-22 op 
133 8d1b399b 2021-07-22 op 	len = sizeof(sun);
134 8d1b399b 2021-07-22 op 	if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len,
135 8d1b399b 2021-07-22 op 	    SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) {
136 8d1b399b 2021-07-22 op 		/*
137 8d1b399b 2021-07-22 op 		 * Pause accept if we are out of file descriptors, or
138 8d1b399b 2021-07-22 op 		 * libevent will haunt us here too.
139 8d1b399b 2021-07-22 op 		 */
140 8d1b399b 2021-07-22 op 		if (errno == ENFILE || errno == EMFILE) {
141 8d1b399b 2021-07-22 op 			struct timeval evtpause = { 1, 0 };
142 8d1b399b 2021-07-22 op 
143 8d1b399b 2021-07-22 op 			event_del(&control_state.ev);
144 8d1b399b 2021-07-22 op 			evtimer_add(&control_state.evt, &evtpause);
145 8d1b399b 2021-07-22 op 		} else if (errno != EWOULDBLOCK && errno != EINTR &&
146 8d1b399b 2021-07-22 op 		    errno != ECONNABORTED)
147 8d1b399b 2021-07-22 op 			log_warn("%s: accept4", __func__);
148 8d1b399b 2021-07-22 op 		return;
149 8d1b399b 2021-07-22 op 	}
150 8d1b399b 2021-07-22 op 
151 8d1b399b 2021-07-22 op 	if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {
152 8d1b399b 2021-07-22 op 		log_warn("%s: calloc", __func__);
153 8d1b399b 2021-07-22 op 		close(connfd);
154 8d1b399b 2021-07-22 op 		return;
155 8d1b399b 2021-07-22 op 	}
156 8d1b399b 2021-07-22 op 
157 8d1b399b 2021-07-22 op 	imsg_init(&c->iev.ibuf, connfd);
158 8d1b399b 2021-07-22 op 	c->iev.handler = control_dispatch_imsg;
159 8d1b399b 2021-07-22 op 	c->iev.events = EV_READ;
160 8d1b399b 2021-07-22 op 	event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events,
161 8d1b399b 2021-07-22 op 	    c->iev.handler, &c->iev);
162 8d1b399b 2021-07-22 op 	event_add(&c->iev.ev, NULL);
163 8d1b399b 2021-07-22 op 
164 8d1b399b 2021-07-22 op 	TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
165 8d1b399b 2021-07-22 op }
166 8d1b399b 2021-07-22 op 
167 8d1b399b 2021-07-22 op struct ctl_conn *
168 8d1b399b 2021-07-22 op control_connbyfd(int fd)
169 8d1b399b 2021-07-22 op {
170 8d1b399b 2021-07-22 op 	struct ctl_conn	*c;
171 8d1b399b 2021-07-22 op 
172 8d1b399b 2021-07-22 op 	TAILQ_FOREACH(c, &ctl_conns, entry) {
173 8d1b399b 2021-07-22 op 		if (c->iev.ibuf.fd == fd)
174 8d1b399b 2021-07-22 op 			break;
175 8d1b399b 2021-07-22 op 	}
176 8d1b399b 2021-07-22 op 
177 8d1b399b 2021-07-22 op 	return (c);
178 8d1b399b 2021-07-22 op }
179 8d1b399b 2021-07-22 op 
180 8d1b399b 2021-07-22 op struct ctl_conn *
181 8d1b399b 2021-07-22 op control_connbypid(pid_t pid)
182 8d1b399b 2021-07-22 op {
183 8d1b399b 2021-07-22 op 	struct ctl_conn	*c;
184 8d1b399b 2021-07-22 op 
185 8d1b399b 2021-07-22 op 	TAILQ_FOREACH(c, &ctl_conns, entry) {
186 8d1b399b 2021-07-22 op 		if (c->iev.ibuf.pid == pid)
187 8d1b399b 2021-07-22 op 			break;
188 8d1b399b 2021-07-22 op 	}
189 8d1b399b 2021-07-22 op 
190 8d1b399b 2021-07-22 op 	return (c);
191 8d1b399b 2021-07-22 op }
192 8d1b399b 2021-07-22 op 
193 8d1b399b 2021-07-22 op void
194 8d1b399b 2021-07-22 op control_close(int fd)
195 8d1b399b 2021-07-22 op {
196 8d1b399b 2021-07-22 op 	struct ctl_conn	*c;
197 8d1b399b 2021-07-22 op 
198 8d1b399b 2021-07-22 op 	if ((c = control_connbyfd(fd)) == NULL) {
199 8d1b399b 2021-07-22 op 		log_warnx("%s: fd %d: not found", __func__, fd);
200 8d1b399b 2021-07-22 op 		return;
201 8d1b399b 2021-07-22 op 	}
202 8d1b399b 2021-07-22 op 
203 8d1b399b 2021-07-22 op 	msgbuf_clear(&c->iev.ibuf.w);
204 8d1b399b 2021-07-22 op 	TAILQ_REMOVE(&ctl_conns, c, entry);
205 8d1b399b 2021-07-22 op 
206 8d1b399b 2021-07-22 op 	event_del(&c->iev.ev);
207 8d1b399b 2021-07-22 op 	close(c->iev.ibuf.fd);
208 8d1b399b 2021-07-22 op 
209 8d1b399b 2021-07-22 op 	/* Some file descriptors are available again. */
210 8d1b399b 2021-07-22 op 	if (evtimer_pending(&control_state.evt, NULL)) {
211 8d1b399b 2021-07-22 op 		evtimer_del(&control_state.evt);
212 8d1b399b 2021-07-22 op 		event_add(&control_state.ev, NULL);
213 8d1b399b 2021-07-22 op 	}
214 8d1b399b 2021-07-22 op 
215 8d1b399b 2021-07-22 op 	free(c);
216 8d1b399b 2021-07-22 op }
217 8d1b399b 2021-07-22 op 
218 8d1b399b 2021-07-22 op void
219 8d1b399b 2021-07-22 op control_dispatch_imsg(int fd, short event, void *bula)
220 8d1b399b 2021-07-22 op {
221 8d1b399b 2021-07-22 op 	struct ctl_conn	*c;
222 8d1b399b 2021-07-22 op 	struct imsg	 imsg;
223 8d1b399b 2021-07-22 op 	ssize_t		 n;
224 8d1b399b 2021-07-22 op 	int		 verbose;
225 8d1b399b 2021-07-22 op 
226 8d1b399b 2021-07-22 op 	if ((c = control_connbyfd(fd)) == NULL) {
227 8d1b399b 2021-07-22 op 		log_warnx("%s: fd %d: not found", __func__, fd);
228 8d1b399b 2021-07-22 op 		return;
229 8d1b399b 2021-07-22 op 	}
230 8d1b399b 2021-07-22 op 
231 8d1b399b 2021-07-22 op 	if (event & EV_READ) {
232 8d1b399b 2021-07-22 op 		if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) ||
233 8d1b399b 2021-07-22 op 		    n == 0) {
234 8d1b399b 2021-07-22 op 			control_close(fd);
235 8d1b399b 2021-07-22 op 			return;
236 8d1b399b 2021-07-22 op 		}
237 8d1b399b 2021-07-22 op 	}
238 8d1b399b 2021-07-22 op 	if (event & EV_WRITE) {
239 8d1b399b 2021-07-22 op 		if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) {
240 8d1b399b 2021-07-22 op 			control_close(fd);
241 8d1b399b 2021-07-22 op 			return;
242 8d1b399b 2021-07-22 op 		}
243 8d1b399b 2021-07-22 op 	}
244 8d1b399b 2021-07-22 op 
245 8d1b399b 2021-07-22 op 	for (;;) {
246 8d1b399b 2021-07-22 op 		if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
247 8d1b399b 2021-07-22 op 			control_close(fd);
248 8d1b399b 2021-07-22 op 			return;
249 8d1b399b 2021-07-22 op 		}
250 8d1b399b 2021-07-22 op 		if (n == 0)
251 8d1b399b 2021-07-22 op 			break;
252 8d1b399b 2021-07-22 op 
253 8d1b399b 2021-07-22 op 		switch (imsg.hdr.type) {
254 8d1b399b 2021-07-22 op 		case IMSG_CTL_RELOAD:
255 8d1b399b 2021-07-22 op 			listener_imsg_compose_main(imsg.hdr.type, 0, NULL, 0);
256 8d1b399b 2021-07-22 op 			break;
257 8d1b399b 2021-07-22 op 		case IMSG_CTL_LOG_VERBOSE:
258 8d1b399b 2021-07-22 op 			if (IMSG_DATA_SIZE(imsg) != sizeof(verbose))
259 8d1b399b 2021-07-22 op 				break;
260 8d1b399b 2021-07-22 op 
261 8d1b399b 2021-07-22 op 			/* Forward to all other processes. */
262 8d1b399b 2021-07-22 op 			listener_imsg_compose_main(imsg.hdr.type, imsg.hdr.pid,
263 8d1b399b 2021-07-22 op 			    imsg.data, IMSG_DATA_SIZE(imsg));
264 8d1b399b 2021-07-22 op 
265 8d1b399b 2021-07-22 op 			/* XXX: send to every client? */
266 8d1b399b 2021-07-22 op 
267 8d1b399b 2021-07-22 op 			memcpy(&verbose, imsg.data, sizeof(verbose));
268 8d1b399b 2021-07-22 op 			log_setverbose(verbose);
269 8d1b399b 2021-07-22 op 			break;
270 8d1b399b 2021-07-22 op 		default:
271 8d1b399b 2021-07-22 op 			log_debug("%s: error handling imsg %d", __func__,
272 8d1b399b 2021-07-22 op 			    imsg.hdr.type);
273 8d1b399b 2021-07-22 op 			break;
274 8d1b399b 2021-07-22 op 		}
275 8d1b399b 2021-07-22 op 		imsg_free(&imsg);
276 8d1b399b 2021-07-22 op 	}
277 8d1b399b 2021-07-22 op 
278 8d1b399b 2021-07-22 op 	imsg_event_add(&c->iev);
279 8d1b399b 2021-07-22 op }
280 8d1b399b 2021-07-22 op 
281 8d1b399b 2021-07-22 op int
282 8d1b399b 2021-07-22 op control_imsg_relay(struct imsg *imsg)
283 8d1b399b 2021-07-22 op {
284 8d1b399b 2021-07-22 op 	struct ctl_conn	*c;
285 8d1b399b 2021-07-22 op 
286 8d1b399b 2021-07-22 op 	if ((c = control_connbypid(imsg->hdr.pid)) == NULL)
287 8d1b399b 2021-07-22 op 		return (0);
288 8d1b399b 2021-07-22 op 
289 8d1b399b 2021-07-22 op 	return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid,
290 8d1b399b 2021-07-22 op 	    -1, imsg->data, IMSG_DATA_SIZE(*imsg)));
291 8d1b399b 2021-07-22 op }