Game of Trees Repos

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Date:: Fri Aug 11 09:26:22 2023 UTC
Message:: gotd: stop logging "unexpected end of file" when a client decides to disconnect
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1 /*
2  * Copyright (c) 2022 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/queue.h>
18 #include <sys/tree.h>
19 #include <sys/time.h>
20 #include <sys/types.h>
21 #include <sys/stat.h>
22 #include <sys/socket.h>
23 #include <sys/un.h>
24 #include <sys/wait.h>
25 
26 #include <fcntl.h>
27 #include <err.h>
28 #include <errno.h>
29 #include <event.h>
30 #include <limits.h>
31 #include <pwd.h>
32 #include <imsg.h>
33 #include <sha1.h>
34 #include <sha2.h>
35 #include <signal.h>
36 #include <siphash.h>
37 #include <stdarg.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <syslog.h>
42 #include <unistd.h>
43 
44 #include "got_error.h"
45 #include "got_opentemp.h"
46 #include "got_path.h"
47 #include "got_repository.h"
48 #include "got_object.h"
49 #include "got_reference.h"
50 
51 #include "got_lib_delta.h"
52 #include "got_lib_object.h"
53 #include "got_lib_object_cache.h"
54 #include "got_lib_hash.h"
55 #include "got_lib_gitproto.h"
56 #include "got_lib_pack.h"
57 #include "got_lib_repository.h"
58 
59 #include "gotd.h"
60 #include "log.h"
61 #include "listen.h"
62 #include "auth.h"
63 #include "session.h"
64 #include "repo_read.h"
65 #include "repo_write.h"
66 
67 #ifndef nitems
68 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
69 #endif
70 
71 enum gotd_client_state {
72 	GOTD_CLIENT_STATE_NEW,
73 	GOTD_CLIENT_STATE_ACCESS_GRANTED,
74 };
75 
76 struct gotd_child_proc {
77 	pid_t				 pid;
78 	enum gotd_procid		 type;
79 	char				 repo_name[NAME_MAX];
80 	char				 repo_path[PATH_MAX];
81 	int				 pipe[2];
82 	struct gotd_imsgev		 iev;
83 	struct event			 tmo;
84 
85 	TAILQ_ENTRY(gotd_child_proc)	 entry;
86 };
87 TAILQ_HEAD(gotd_procs, gotd_child_proc) procs;
88 
89 struct gotd_client {
90 	STAILQ_ENTRY(gotd_client)	 entry;
91 	enum gotd_client_state		 state;
92 	uint32_t			 id;
93 	int				 fd;
94 	struct gotd_imsgev		 iev;
95 	struct event			 tmo;
96 	uid_t				 euid;
97 	gid_t				 egid;
98 	struct gotd_child_proc		*repo;
99 	struct gotd_child_proc		*auth;
100 	struct gotd_child_proc		*session;
101 	int				 required_auth;
102 };
103 STAILQ_HEAD(gotd_clients, gotd_client);
104 
105 static struct gotd_clients gotd_clients[GOTD_CLIENT_TABLE_SIZE];
106 static SIPHASH_KEY clients_hash_key;
107 volatile int client_cnt;
108 static struct timeval auth_timeout = { 5, 0 };
109 static struct gotd gotd;
110 
111 void gotd_sighdlr(int sig, short event, void *arg);
112 static void gotd_shutdown(void);
113 static const struct got_error *start_session_child(struct gotd_client *,
114     struct gotd_repo *, char *, const char *, int, int);
115 static const struct got_error *start_repo_child(struct gotd_client *,
116     enum gotd_procid, struct gotd_repo *, char *, const char *, int, int);
117 static const struct got_error *start_auth_child(struct gotd_client *, int,
118     struct gotd_repo *, char *, const char *, int, int);
119 static void kill_proc(struct gotd_child_proc *, int);
120 static void disconnect(struct gotd_client *);
121 
122 __dead static void
123 usage(void)
124 {
125 	fprintf(stderr, "usage: %s [-dnv] [-f config-file]\n", getprogname());
126 	exit(1);
127 }
128 
129 static int
130 unix_socket_listen(const char *unix_socket_path, uid_t uid, gid_t gid)
131 {
132 	struct sockaddr_un sun;
133 	int fd = -1;
134 	mode_t old_umask, mode;
135 
136 	fd = socket(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK| SOCK_CLOEXEC, 0);
137 	if (fd == -1) {
138 		log_warn("socket");
139 		return -1;
140 	}
141 
142 	sun.sun_family = AF_UNIX;
143 	if (strlcpy(sun.sun_path, unix_socket_path,
144 	    sizeof(sun.sun_path)) >= sizeof(sun.sun_path)) {
145 		log_warnx("%s: name too long", unix_socket_path);
146 		close(fd);
147 		return -1;
148 	}
149 
150 	if (unlink(unix_socket_path) == -1) {
151 		if (errno != ENOENT) {
152 			log_warn("unlink %s", unix_socket_path);
153 			close(fd);
154 			return -1;
155 		}
156 	}
157 
158 	old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
159 	mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH;
160 
161 	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
162 		log_warn("bind: %s", unix_socket_path);
163 		close(fd);
164 		umask(old_umask);
165 		return -1;
166 	}
167 
168 	umask(old_umask);
169 
170 	if (chmod(unix_socket_path, mode) == -1) {
171 		log_warn("chmod %o %s", mode, unix_socket_path);
172 		close(fd);
173 		unlink(unix_socket_path);
174 		return -1;
175 	}
176 
177 	if (chown(unix_socket_path, uid, gid) == -1) {
178 		log_warn("chown %s uid=%d gid=%d", unix_socket_path, uid, gid);
179 		close(fd);
180 		unlink(unix_socket_path);
181 		return -1;
182 	}
183 
184 	if (listen(fd, GOTD_UNIX_SOCKET_BACKLOG) == -1) {
185 		log_warn("listen");
186 		close(fd);
187 		unlink(unix_socket_path);
188 		return -1;
189 	}
190 
191 	return fd;
192 }
193 
194 static uint64_t
195 client_hash(uint32_t client_id)
196 {
197 	return SipHash24(&clients_hash_key, &client_id, sizeof(client_id));
198 }
199 
200 static void
201 add_client(struct gotd_client *client)
202 {
203 	uint64_t slot = client_hash(client->id) % nitems(gotd_clients);
204 	STAILQ_INSERT_HEAD(&gotd_clients[slot], client, entry);
205 	client_cnt++;
206 }
207 
208 static struct gotd_client *
209 find_client(uint32_t client_id)
210 {
211 	uint64_t slot;
212 	struct gotd_client *c;
213 
214 	slot = client_hash(client_id) % nitems(gotd_clients);
215 	STAILQ_FOREACH(c, &gotd_clients[slot], entry) {
216 		if (c->id == client_id)
217 			return c;
218 	}
219 
220 	return NULL;
221 }
222 
223 static struct gotd_client *
224 find_client_by_proc_fd(int fd)
225 {
226 	uint64_t slot;
227 
228 	for (slot = 0; slot < nitems(gotd_clients); slot++) {
229 		struct gotd_client *c;
230 
231 		STAILQ_FOREACH(c, &gotd_clients[slot], entry) {
232 			if (c->repo && c->repo->iev.ibuf.fd == fd)
233 				return c;
234 			if (c->auth && c->auth->iev.ibuf.fd == fd)
235 				return c;
236 			if (c->session && c->session->iev.ibuf.fd == fd)
237 				return c;
238 		}
239 	}
240 
241 	return NULL;
242 }
243 
244 static int
245 client_is_reading(struct gotd_client *client)
246 {
247 	return (client->required_auth &
248 	    (GOTD_AUTH_READ | GOTD_AUTH_WRITE)) == GOTD_AUTH_READ;
249 }
250 
251 static int
252 client_is_writing(struct gotd_client *client)
253 {
254 	return (client->required_auth &
255 	    (GOTD_AUTH_READ | GOTD_AUTH_WRITE)) ==
256 	    (GOTD_AUTH_READ | GOTD_AUTH_WRITE);
257 }
258 
259 static const struct got_error *
260 ensure_client_is_not_writing(struct gotd_client *client)
261 {
262 	if (client_is_writing(client)) {
263 		return got_error_fmt(GOT_ERR_BAD_PACKET,
264 		    "uid %d made a read-request but is writing to "
265 		    "a repository", client->euid);
266 	}
267 
268 	return NULL;
269 }
270 
271 static const struct got_error *
272 ensure_client_is_not_reading(struct gotd_client *client)
273 {
274 	if (client_is_reading(client)) {
275 		return got_error_fmt(GOT_ERR_BAD_PACKET,
276 		    "uid %d made a write-request but is reading from "
277 		    "a repository", client->euid);
278 	}
279 
280 	return NULL;
281 }
282 
283 static void
284 proc_done(struct gotd_child_proc *proc)
285 {
286 	struct gotd_client *client;
287 
288 	TAILQ_REMOVE(&procs, proc, entry);
289 
290 	client = find_client_by_proc_fd(proc->iev.ibuf.fd);
291 	if (client != NULL) {
292 		if (proc == client->repo)
293 			client->repo = NULL;
294 		if (proc == client->auth)
295 			client->auth = NULL;
296 		if (proc == client->session)
297 			client->session = NULL;
298 		disconnect(client);
299 	}
300 
301 	evtimer_del(&proc->tmo);
302 
303 	if (proc->iev.ibuf.fd != -1) {
304 		event_del(&proc->iev.ev);
305 		msgbuf_clear(&proc->iev.ibuf.w);
306 		close(proc->iev.ibuf.fd);
307 	}
308 
309 	free(proc);
310 }
311 
312 static void
313 kill_repo_proc(struct gotd_client *client)
314 {
315 	if (client->repo == NULL)
316 		return;
317 
318 	kill_proc(client->repo, 0);
319 	client->repo = NULL;
320 }
321 
322 static void
323 kill_auth_proc(struct gotd_client *client)
324 {
325 	if (client->auth == NULL)
326 		return;
327 
328 	kill_proc(client->auth, 0);
329 	client->auth = NULL;
330 }
331 
332 static void
333 kill_session_proc(struct gotd_client *client)
334 {
335 	if (client->session == NULL)
336 		return;
337 
338 	kill_proc(client->session, 0);
339 	client->session = NULL;
340 }
341 
342 static void
343 disconnect(struct gotd_client *client)
344 {
345 	struct gotd_imsg_disconnect idisconnect;
346 	struct gotd_child_proc *listen_proc = gotd.listen_proc;
347 	uint64_t slot;
348 
349 	log_debug("uid %d: disconnecting", client->euid);
350 
351 	kill_auth_proc(client);
352 	kill_session_proc(client);
353 	kill_repo_proc(client);
354 
355 	idisconnect.client_id = client->id;
356 	if (gotd_imsg_compose_event(&listen_proc->iev,
357 	    GOTD_IMSG_DISCONNECT, PROC_GOTD, -1,
358 	    &idisconnect, sizeof(idisconnect)) == -1)
359 		log_warn("imsg compose DISCONNECT");
360 
361 	slot = client_hash(client->id) % nitems(gotd_clients);
362 	STAILQ_REMOVE(&gotd_clients[slot], client, gotd_client, entry);
363 	imsg_clear(&client->iev.ibuf);
364 	event_del(&client->iev.ev);
365 	evtimer_del(&client->tmo);
366 	if (client->fd != -1)
367 		close(client->fd);
368 	else if (client->iev.ibuf.fd != -1)
369 		close(client->iev.ibuf.fd);
370 	free(client);
371 	client_cnt--;
372 }
373 
374 static void
375 disconnect_on_error(struct gotd_client *client, const struct got_error *err)
376 {
377 	struct imsgbuf ibuf;
378 
379 	if (err->code != GOT_ERR_EOF) {
380 		log_warnx("uid %d: %s", client->euid, err->msg);
381 		if (client->fd != -1) {
382 			imsg_init(&ibuf, client->fd);
383 			gotd_imsg_send_error(&ibuf, 0, PROC_GOTD, err);
384 			imsg_clear(&ibuf);
385 		}
386 	}
387 	disconnect(client);
388 }
389 
390 static const struct got_error *
391 send_repo_info(struct gotd_imsgev *iev, struct gotd_repo *repo)
392 {
393 	const struct got_error *err = NULL;
394 	struct gotd_imsg_info_repo irepo;
395 
396 	memset(&irepo, 0, sizeof(irepo));
397 
398 	if (strlcpy(irepo.repo_name, repo->name, sizeof(irepo.repo_name))
399 	    >= sizeof(irepo.repo_name))
400 		return got_error_msg(GOT_ERR_NO_SPACE, "repo name too long");
401 	if (strlcpy(irepo.repo_path, repo->path, sizeof(irepo.repo_path))
402 	    >= sizeof(irepo.repo_path))
403 		return got_error_msg(GOT_ERR_NO_SPACE, "repo path too long");
404 
405 	if (gotd_imsg_compose_event(iev, GOTD_IMSG_INFO_REPO, PROC_GOTD, -1,
406 	    &irepo, sizeof(irepo)) == -1) {
407 		err = got_error_from_errno("imsg compose INFO_REPO");
408 		if (err)
409 			return err;
410 	}
411 
412 	return NULL;
413 }
414 
415 static const struct got_error *
416 send_client_info(struct gotd_imsgev *iev, struct gotd_client *client)
417 {
418 	const struct got_error *err = NULL;
419 	struct gotd_imsg_info_client iclient;
420 	struct gotd_child_proc *proc;
421 
422 	memset(&iclient, 0, sizeof(iclient));
423 	iclient.euid = client->euid;
424 	iclient.egid = client->egid;
425 
426 	proc = client->repo;
427 	if (proc) {
428 		if (strlcpy(iclient.repo_name, proc->repo_path,
429 		    sizeof(iclient.repo_name)) >= sizeof(iclient.repo_name)) {
430 			return got_error_msg(GOT_ERR_NO_SPACE,
431 			    "repo name too long");
432 		}
433 		if (client_is_writing(client))
434 			iclient.is_writing = 1;
435 
436 		iclient.repo_child_pid = proc->pid;
437 	}
438 
439 	if (client->session)
440 		iclient.session_child_pid = client->session->pid;
441 
442 	if (gotd_imsg_compose_event(iev, GOTD_IMSG_INFO_CLIENT, PROC_GOTD, -1,
443 	    &iclient, sizeof(iclient)) == -1) {
444 		err = got_error_from_errno("imsg compose INFO_CLIENT");
445 		if (err)
446 			return err;
447 	}
448 
449 	return NULL;
450 }
451 
452 static const struct got_error *
453 send_info(struct gotd_client *client)
454 {
455 	const struct got_error *err = NULL;
456 	struct gotd_imsg_info info;
457 	uint64_t slot;
458 	struct gotd_repo *repo;
459 
460 	if (client->euid != 0)
461 		return got_error_set_errno(EPERM, "info");
462 
463 	info.pid = gotd.pid;
464 	info.verbosity = gotd.verbosity;
465 	info.nrepos = gotd.nrepos;
466 	info.nclients = client_cnt - 1;
467 
468 	if (gotd_imsg_compose_event(&client->iev, GOTD_IMSG_INFO, PROC_GOTD, -1,
469 	    &info, sizeof(info)) == -1) {
470 		err = got_error_from_errno("imsg compose INFO");
471 		if (err)
472 			return err;
473 	}
474 
475 	TAILQ_FOREACH(repo, &gotd.repos, entry) {
476 		err = send_repo_info(&client->iev, repo);
477 		if (err)
478 			return err;
479 	}
480 
481 	for (slot = 0; slot < nitems(gotd_clients); slot++) {
482 		struct gotd_client *c;
483 		STAILQ_FOREACH(c, &gotd_clients[slot], entry) {
484 			if (c->id == client->id)
485 				continue;
486 			err = send_client_info(&client->iev, c);
487 			if (err)
488 				return err;
489 		}
490 	}
491 
492 	return NULL;
493 }
494 
495 static const struct got_error *
496 stop_gotd(struct gotd_client *client)
497 {
498 
499 	if (client->euid != 0)
500 		return got_error_set_errno(EPERM, "stop");
501 
502 	gotd_shutdown();
503 	/* NOTREACHED */
504 	return NULL;
505 }
506 
507 static const struct got_error *
508 start_client_authentication(struct gotd_client *client, struct imsg *imsg)
509 {
510 	const struct got_error *err;
511 	struct gotd_imsg_list_refs ireq;
512 	struct gotd_repo *repo = NULL;
513 	size_t datalen;
514 
515 	log_debug("list-refs request from uid %d", client->euid);
516 
517 	if (client->state != GOTD_CLIENT_STATE_NEW)
518 		return got_error_msg(GOT_ERR_BAD_REQUEST,
519 		    "unexpected list-refs request received");
520 
521 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
522 	if (datalen != sizeof(ireq))
523 		return got_error(GOT_ERR_PRIVSEP_LEN);
524 
525 	memcpy(&ireq, imsg->data, datalen);
526 
527 	if (ireq.client_is_reading) {
528 		err = ensure_client_is_not_writing(client);
529 		if (err)
530 			return err;
531 		repo = gotd_find_repo_by_name(ireq.repo_name, &gotd);
532 		if (repo == NULL)
533 			return got_error(GOT_ERR_NOT_GIT_REPO);
534 		err = start_auth_child(client, GOTD_AUTH_READ, repo,
535 		    gotd.argv0, gotd.confpath, gotd.daemonize,
536 		    gotd.verbosity);
537 		if (err)
538 			return err;
539 	} else {
540 		err = ensure_client_is_not_reading(client);
541 		if (err)
542 			return err;
543 		repo = gotd_find_repo_by_name(ireq.repo_name, &gotd);
544 		if (repo == NULL)
545 			return got_error(GOT_ERR_NOT_GIT_REPO);
546 		err = start_auth_child(client,
547 		    GOTD_AUTH_READ | GOTD_AUTH_WRITE,
548 		    repo, gotd.argv0, gotd.confpath, gotd.daemonize,
549 		    gotd.verbosity);
550 		if (err)
551 			return err;
552 	}
553 
554 	evtimer_add(&client->tmo, &auth_timeout);
555 
556 	/* Flow continues upon authentication success/failure or timeout. */
557 	return NULL;
558 }
559 
560 static void
561 gotd_request(int fd, short events, void *arg)
562 {
563 	struct gotd_imsgev *iev = arg;
564 	struct imsgbuf *ibuf = &iev->ibuf;
565 	struct gotd_client *client = iev->handler_arg;
566 	const struct got_error *err = NULL;
567 	struct imsg imsg;
568 	ssize_t n;
569 
570 	if (events & EV_WRITE) {
571 		while (ibuf->w.queued) {
572 			n = msgbuf_write(&ibuf->w);
573 			if (n == -1 && errno == EPIPE) {
574 				/*
575 				 * The client has closed its socket.
576 				 * This can happen when Git clients are
577 				 * done sending pack file data.
578 				 */
579 				msgbuf_clear(&ibuf->w);
580 				continue;
581 			} else if (n == -1 && errno != EAGAIN) {
582 				err = got_error_from_errno("imsg_flush");
583 				disconnect_on_error(client, err);
584 				return;
585 			}
586 			if (n == 0) {
587 				/* Connection closed. */
588 				err = got_error(GOT_ERR_EOF);
589 				disconnect_on_error(client, err);
590 				return;
591 			}
592 		}
593 
594 		/* Disconnect gotctl(8) now that messages have been sent. */
595 		if (!client_is_reading(client) && !client_is_writing(client)) {
596 			disconnect(client);
597 			return;
598 		}
599 	}
600 
601 	if ((events & EV_READ) == 0)
602 		return;
603 
604 	memset(&imsg, 0, sizeof(imsg));
605 
606 	while (err == NULL) {
607 		err = gotd_imsg_recv(&imsg, ibuf, 0);
608 		if (err) {
609 			if (err->code == GOT_ERR_PRIVSEP_READ)
610 				err = NULL;
611 			break;
612 		}
613 
614 		evtimer_del(&client->tmo);
615 
616 		switch (imsg.hdr.type) {
617 		case GOTD_IMSG_INFO:
618 			err = send_info(client);
619 			break;
620 		case GOTD_IMSG_STOP:
621 			err = stop_gotd(client);
622 			break;
623 		case GOTD_IMSG_LIST_REFS:
624 			err = start_client_authentication(client, &imsg);
625 			break;
626 		default:
627 			log_debug("unexpected imsg %d", imsg.hdr.type);
628 			err = got_error(GOT_ERR_PRIVSEP_MSG);
629 			break;
630 		}
631 
632 		imsg_free(&imsg);
633 	}
634 
635 	if (err) {
636 		disconnect_on_error(client, err);
637 	} else {
638 		gotd_imsg_event_add(&client->iev);
639 	}
640 }
641 
642 static void
643 gotd_auth_timeout(int fd, short events, void *arg)
644 {
645 	struct gotd_client *client = arg;
646 
647 	log_debug("disconnecting uid %d due to authentication timeout",
648 	    client->euid);
649 	disconnect(client);
650 }
651 
652 static const struct got_error *
653 recv_connect(uint32_t *client_id, struct imsg *imsg)
654 {
655 	const struct got_error *err = NULL;
656 	struct gotd_imsg_connect iconnect;
657 	size_t datalen;
658 	int s = -1;
659 	struct gotd_client *client = NULL;
660 
661 	*client_id = 0;
662 
663 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
664 	if (datalen != sizeof(iconnect))
665 		return got_error(GOT_ERR_PRIVSEP_LEN);
666 	memcpy(&iconnect, imsg->data, sizeof(iconnect));
667 
668 	s = imsg->fd;
669 	if (s == -1) {
670 		err = got_error(GOT_ERR_PRIVSEP_NO_FD);
671 		goto done;
672 	}
673 
674 	if (find_client(iconnect.client_id)) {
675 		err = got_error_msg(GOT_ERR_CLIENT_ID, "duplicate client ID");
676 		goto done;
677 	}
678 
679 	client = calloc(1, sizeof(*client));
680 	if (client == NULL) {
681 		err = got_error_from_errno("calloc");
682 		goto done;
683 	}
684 
685 	*client_id = iconnect.client_id;
686 
687 	client->state = GOTD_CLIENT_STATE_NEW;
688 	client->id = iconnect.client_id;
689 	client->fd = s;
690 	s = -1;
691 	/* The auth process will verify UID/GID for us. */
692 	client->euid = iconnect.euid;
693 	client->egid = iconnect.egid;
694 
695 	imsg_init(&client->iev.ibuf, client->fd);
696 	client->iev.handler = gotd_request;
697 	client->iev.events = EV_READ;
698 	client->iev.handler_arg = client;
699 
700 	event_set(&client->iev.ev, client->fd, EV_READ, gotd_request,
701 	    &client->iev);
702 	gotd_imsg_event_add(&client->iev);
703 
704 	evtimer_set(&client->tmo, gotd_auth_timeout, client);
705 
706 	add_client(client);
707 	log_debug("%s: new client uid %d connected on fd %d", __func__,
708 	    client->euid, client->fd);
709 done:
710 	if (err) {
711 		struct gotd_child_proc *listen_proc = gotd.listen_proc;
712 		struct gotd_imsg_disconnect idisconnect;
713 
714 		idisconnect.client_id = client->id;
715 		if (gotd_imsg_compose_event(&listen_proc->iev,
716 		    GOTD_IMSG_DISCONNECT, PROC_GOTD, -1,
717 		    &idisconnect, sizeof(idisconnect)) == -1)
718 			log_warn("imsg compose DISCONNECT");
719 
720 		if (s != -1)
721 			close(s);
722 	}
723 
724 	return err;
725 }
726 
727 static const char *gotd_proc_names[PROC_MAX] = {
728 	"parent",
729 	"listen",
730 	"auth",
731 	"session_read",
732 	"session_write",
733 	"repo_read",
734 	"repo_write",
735 	"gitwrapper"
736 };
737 
738 static void
739 kill_proc(struct gotd_child_proc *proc, int fatal)
740 {
741 	struct timeval tv = { 5, 0 };
742 
743 	log_debug("kill -%d %d", fatal ? SIGKILL : SIGTERM, proc->pid);
744 
745 	if (proc->iev.ibuf.fd != -1) {
746 		event_del(&proc->iev.ev);
747 		msgbuf_clear(&proc->iev.ibuf.w);
748 		close(proc->iev.ibuf.fd);
749 		proc->iev.ibuf.fd = -1;
750 	}
751 
752 	if (!evtimer_pending(&proc->tmo, NULL) && !fatal)
753 		evtimer_add(&proc->tmo, &tv);
754 
755 	if (fatal) {
756 		log_warnx("sending SIGKILL to PID %d", proc->pid);
757 		kill(proc->pid, SIGKILL);
758 	} else
759 		kill(proc->pid, SIGTERM);
760 }
761 
762 static void
763 kill_proc_timeout(int fd, short ev, void *d)
764 {
765 	struct gotd_child_proc *proc = d;
766 
767 	log_warnx("timeout waiting for PID %d to terminate;"
768 	    " retrying with force", proc->pid);
769 	kill_proc(proc, 1);
770 }
771 
772 static void
773 gotd_shutdown(void)
774 {
775 	uint64_t slot;
776 
777 	log_debug("shutting down");
778 	for (slot = 0; slot < nitems(gotd_clients); slot++) {
779 		struct gotd_client *c, *tmp;
780 
781 		STAILQ_FOREACH_SAFE(c, &gotd_clients[slot], entry, tmp)
782 			disconnect(c);
783 	}
784 
785 	kill_proc(gotd.listen_proc, 0);
786 
787 	log_info("terminating");
788 	exit(0);
789 }
790 
791 static struct gotd_child_proc *
792 find_proc_by_pid(pid_t pid)
793 {
794 	struct gotd_child_proc *proc = NULL;
795 
796 	TAILQ_FOREACH(proc, &procs, entry)
797 		if (proc->pid == pid)
798 			break;
799 
800 	return proc;
801 }
802 
803 void
804 gotd_sighdlr(int sig, short event, void *arg)
805 {
806 	struct gotd_child_proc *proc;
807 	pid_t pid;
808 	int status;
809 
810 	/*
811 	 * Normal signal handler rules don't apply because libevent
812 	 * decouples for us.
813 	 */
814 
815 	switch (sig) {
816 	case SIGHUP:
817 		log_info("%s: ignoring SIGHUP", __func__);
818 		break;
819 	case SIGUSR1:
820 		log_info("%s: ignoring SIGUSR1", __func__);
821 		break;
822 	case SIGTERM:
823 	case SIGINT:
824 		gotd_shutdown();
825 		break;
826 	case SIGCHLD:
827 		for (;;) {
828 			pid = waitpid(WAIT_ANY, &status, WNOHANG);
829 			if (pid == -1) {
830 				if (errno == EINTR)
831 					continue;
832 				if (errno == ECHILD)
833 					break;
834 				fatal("waitpid");
835 			}
836 			if (pid == 0)
837 				break;
838 
839 			log_debug("reaped pid %d", pid);
840 			proc = find_proc_by_pid(pid);
841 			if (proc == NULL) {
842 				log_info("caught exit of unknown child %d",
843 				    pid);
844 				continue;
845 			}
846 
847 			if (WIFSIGNALED(status)) {
848 				log_warnx("child PID %d terminated with"
849 				    " signal %d", pid, WTERMSIG(status));
850 			}
851 
852 			proc_done(proc);
853 		}
854 		break;
855 	default:
856 		fatalx("unexpected signal");
857 	}
858 }
859 
860 static const struct got_error *
861 ensure_proc_is_reading(struct gotd_client *client,
862     struct gotd_child_proc *proc)
863 {
864 	if (!client_is_reading(client)) {
865 		kill_proc(proc, 1);
866 		return got_error_fmt(GOT_ERR_BAD_PACKET,
867 		    "PID %d handled a read-request for uid %d but this "
868 		    "user is not reading from a repository", proc->pid,
869 		    client->euid);
870 	}
871 
872 	return NULL;
873 }
874 
875 static const struct got_error *
876 ensure_proc_is_writing(struct gotd_client *client,
877     struct gotd_child_proc *proc)
878 {
879 	if (!client_is_writing(client)) {
880 		kill_proc(proc, 1);
881 		return got_error_fmt(GOT_ERR_BAD_PACKET,
882 		    "PID %d handled a write-request for uid %d but this "
883 		    "user is not writing to a repository", proc->pid,
884 		    client->euid);
885 	}
886 
887 	return NULL;
888 }
889 
890 static int
891 verify_imsg_src(struct gotd_client *client, struct gotd_child_proc *proc,
892     struct imsg *imsg)
893 {
894 	const struct got_error *err;
895 	int ret = 0;
896 
897 	if (proc->type == PROC_REPO_READ || proc->type == PROC_REPO_WRITE) {
898 		if (client->repo == NULL)
899 			fatalx("no process found for uid %d", client->euid);
900 		if (proc->pid != client->repo->pid) {
901 			kill_proc(proc, 1);
902 			log_warnx("received message from PID %d for uid %d, "
903 			    "while PID %d is the process serving this user",
904 			    proc->pid, client->euid, client->repo->pid);
905 			return 0;
906 		}
907 	}
908 	if (proc->type == PROC_SESSION_READ ||
909 	    proc->type == PROC_SESSION_WRITE) {
910 		if (client->session == NULL) {
911 			log_warnx("no session found for uid %d", client->euid);
912 			return 0;
913 		}
914 		if (proc->pid != client->session->pid) {
915 			kill_proc(proc, 1);
916 			log_warnx("received message from PID %d for uid %d, "
917 			    "while PID %d is the process serving this user",
918 			    proc->pid, client->euid, client->session->pid);
919 			return 0;
920 		}
921 	}
922 
923 	switch (imsg->hdr.type) {
924 	case GOTD_IMSG_ERROR:
925 		ret = 1;
926 		break;
927 	case GOTD_IMSG_CONNECT:
928 		if (proc->type != PROC_LISTEN) {
929 			err = got_error_fmt(GOT_ERR_BAD_PACKET,
930 			    "new connection for uid %d from PID %d "
931 			    "which is not the listen process",
932 			    proc->pid, client->euid);
933 		} else
934 			ret = 1;
935 		break;
936 	case GOTD_IMSG_ACCESS_GRANTED:
937 		if (proc->type != PROC_AUTH) {
938 			err = got_error_fmt(GOT_ERR_BAD_PACKET,
939 			    "authentication of uid %d from PID %d "
940 			    "which is not the auth process",
941 			    proc->pid, client->euid);
942 		} else
943 			ret = 1;
944 		break;
945 	case GOTD_IMSG_CLIENT_SESSION_READY:
946 		if (proc->type != PROC_SESSION_READ &&
947 		    proc->type != PROC_SESSION_WRITE) {
948 			err = got_error_fmt(GOT_ERR_BAD_PACKET,
949 			    "unexpected \"ready\" signal from PID %d",
950 			    proc->pid);
951 		} else
952 			ret = 1;
953 		break;
954 	case GOTD_IMSG_REPO_CHILD_READY:
955 		if (proc->type != PROC_REPO_READ &&
956 		    proc->type != PROC_REPO_WRITE) {
957 			err = got_error_fmt(GOT_ERR_BAD_PACKET,
958 			    "unexpected \"ready\" signal from PID %d",
959 			    proc->pid);
960 		} else
961 			ret = 1;
962 		break;
963 	case GOTD_IMSG_PACKFILE_DONE:
964 		err = ensure_proc_is_reading(client, proc);
965 		if (err)
966 			log_warnx("uid %d: %s", client->euid, err->msg);
967 		else
968 			ret = 1;
969 		break;
970 	case GOTD_IMSG_PACKFILE_INSTALL:
971 	case GOTD_IMSG_REF_UPDATES_START:
972 	case GOTD_IMSG_REF_UPDATE:
973 		err = ensure_proc_is_writing(client, proc);
974 		if (err)
975 			log_warnx("uid %d: %s", client->euid, err->msg);
976 		else
977 			ret = 1;
978 		break;
979 	default:
980 		log_debug("%s: unexpected imsg %d", __func__, imsg->hdr.type);
981 		break;
982 	}
983 
984 	return ret;
985 }
986 
987 static const struct got_error *
988 connect_repo_child(struct gotd_client *client,
989     struct gotd_child_proc *repo_proc)
990 {
991 	static const struct got_error *err;
992 	struct gotd_imsgev *session_iev = &client->session->iev;
993 	struct gotd_imsg_connect_repo_child ireq;
994 	int pipe[2];
995 
996 	if (client->state != GOTD_CLIENT_STATE_ACCESS_GRANTED)
997 		return got_error_msg(GOT_ERR_BAD_REQUEST,
998 		    "unexpected repo child ready signal received");
999 
1000 	if (socketpair(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK,
1001 	    PF_UNSPEC, pipe) == -1)
1002 		fatal("socketpair");
1003 
1004 	memset(&ireq, 0, sizeof(ireq));
1005 	ireq.client_id = client->id;
1006 	ireq.proc_id = repo_proc->type;
1007 
1008 	/* Pass repo child pipe to session child process. */
1009 	if (gotd_imsg_compose_event(session_iev, GOTD_IMSG_CONNECT_REPO_CHILD,
1010 	    PROC_GOTD, pipe[0], &ireq, sizeof(ireq)) == -1) {
1011 		err = got_error_from_errno("imsg compose CONNECT_REPO_CHILD");
1012 		close(pipe[0]);
1013 		close(pipe[1]);
1014 		return err;
1015 	}
1016 
1017 	/* Pass session child pipe to repo child process. */
1018 	if (gotd_imsg_compose_event(&repo_proc->iev,
1019 	    GOTD_IMSG_CONNECT_REPO_CHILD, PROC_GOTD, pipe[1], NULL, 0) == -1) {
1020 		err = got_error_from_errno("imsg compose CONNECT_REPO_CHILD");
1021 		close(pipe[1]);
1022 		return err;
1023 	}
1024 
1025 	return NULL;
1026 }
1027 
1028 static void
1029 gotd_dispatch_listener(int fd, short event, void *arg)
1030 {
1031 	struct gotd_imsgev *iev = arg;
1032 	struct imsgbuf *ibuf = &iev->ibuf;
1033 	struct gotd_child_proc *proc = gotd.listen_proc;
1034 	ssize_t n;
1035 	int shut = 0;
1036 	struct imsg imsg;
1037 
1038 	if (proc->iev.ibuf.fd != fd)
1039 		fatalx("%s: unexpected fd %d", __func__, fd);
1040 
1041 	if (event & EV_READ) {
1042 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
1043 			fatal("imsg_read error");
1044 		if (n == 0) {
1045 			/* Connection closed. */
1046 			shut = 1;
1047 			goto done;
1048 		}
1049 	}
1050 
1051 	if (event & EV_WRITE) {
1052 		n = msgbuf_write(&ibuf->w);
1053 		if (n == -1 && errno != EAGAIN)
1054 			fatal("msgbuf_write");
1055 		if (n == 0) {
1056 			/* Connection closed. */
1057 			shut = 1;
1058 			goto done;
1059 		}
1060 	}
1061 
1062 	for (;;) {
1063 		const struct got_error *err = NULL;
1064 		struct gotd_client *client = NULL;
1065 		uint32_t client_id = 0;
1066 		int do_disconnect = 0;
1067 
1068 		if ((n = imsg_get(ibuf, &imsg)) == -1)
1069 			fatal("%s: imsg_get error", __func__);
1070 		if (n == 0)	/* No more messages. */
1071 			break;
1072 
1073 		switch (imsg.hdr.type) {
1074 		case GOTD_IMSG_ERROR:
1075 			do_disconnect = 1;
1076 			err = gotd_imsg_recv_error(&client_id, &imsg);
1077 			break;
1078 		case GOTD_IMSG_CONNECT:
1079 			err = recv_connect(&client_id, &imsg);
1080 			break;
1081 		default:
1082 			log_debug("unexpected imsg %d", imsg.hdr.type);
1083 			break;
1084 		}
1085 
1086 		client = find_client(client_id);
1087 		if (client == NULL) {
1088 			log_warnx("%s: client not found", __func__);
1089 			imsg_free(&imsg);
1090 			continue;
1091 		}
1092 
1093 		if (err)
1094 			log_warnx("uid %d: %s", client->euid, err->msg);
1095 
1096 		if (do_disconnect) {
1097 			if (err)
1098 				disconnect_on_error(client, err);
1099 			else
1100 				disconnect(client);
1101 		}
1102 
1103 		imsg_free(&imsg);
1104 	}
1105 done:
1106 	if (!shut) {
1107 		gotd_imsg_event_add(iev);
1108 	} else {
1109 		/* This pipe is dead. Remove its event handler */
1110 		event_del(&iev->ev);
1111 		event_loopexit(NULL);
1112 	}
1113 }
1114 
1115 static void
1116 gotd_dispatch_auth_child(int fd, short event, void *arg)
1117 {
1118 	const struct got_error *err = NULL;
1119 	struct gotd_imsgev *iev = arg;
1120 	struct imsgbuf *ibuf = &iev->ibuf;
1121 	struct gotd_client *client;
1122 	struct gotd_repo *repo = NULL;
1123 	ssize_t n;
1124 	int shut = 0;
1125 	struct imsg imsg;
1126 	uint32_t client_id = 0;
1127 	int do_disconnect = 0;
1128 
1129 	client = find_client_by_proc_fd(fd);
1130 	if (client == NULL) {
1131 		/* Can happen during process teardown. */
1132 		warnx("cannot find client for fd %d", fd);
1133 		shut = 1;
1134 		goto done;
1135 	}
1136 
1137 	if (client->auth == NULL)
1138 		fatalx("cannot find auth child process for fd %d", fd);
1139 
1140 	if (event & EV_READ) {
1141 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
1142 			fatal("imsg_read error");
1143 		if (n == 0) {
1144 			/* Connection closed. */
1145 			shut = 1;
1146 			goto done;
1147 		}
1148 	}
1149 
1150 	if (event & EV_WRITE) {
1151 		n = msgbuf_write(&ibuf->w);
1152 		if (n == -1 && errno != EAGAIN)
1153 			fatal("msgbuf_write");
1154 		if (n == 0) {
1155 			/* Connection closed. */
1156 			shut = 1;
1157 		}
1158 		goto done;
1159 	}
1160 
1161 	if (client->auth->iev.ibuf.fd != fd)
1162 		fatalx("%s: unexpected fd %d", __func__, fd);
1163 
1164 	if ((n = imsg_get(ibuf, &imsg)) == -1)
1165 		fatal("%s: imsg_get error", __func__);
1166 	if (n == 0)	/* No more messages. */
1167 		return;
1168 
1169 	evtimer_del(&client->tmo);
1170 
1171 	switch (imsg.hdr.type) {
1172 	case GOTD_IMSG_ERROR:
1173 		do_disconnect = 1;
1174 		err = gotd_imsg_recv_error(&client_id, &imsg);
1175 		break;
1176 	case GOTD_IMSG_ACCESS_GRANTED:
1177 		client->state = GOTD_CLIENT_STATE_ACCESS_GRANTED;
1178 		break;
1179 	default:
1180 		do_disconnect = 1;
1181 		log_debug("unexpected imsg %d", imsg.hdr.type);
1182 		break;
1183 	}
1184 
1185 	if (!verify_imsg_src(client, client->auth, &imsg)) {
1186 		do_disconnect = 1;
1187 		log_debug("dropping imsg type %d from PID %d",
1188 		    imsg.hdr.type, client->auth->pid);
1189 	}
1190 	imsg_free(&imsg);
1191 
1192 	if (do_disconnect) {
1193 		if (err)
1194 			disconnect_on_error(client, err);
1195 		else
1196 			disconnect(client);
1197 		return;
1198 	}
1199 
1200 	repo = gotd_find_repo_by_name(client->auth->repo_name, &gotd);
1201 	if (repo == NULL) {
1202 		err = got_error(GOT_ERR_NOT_GIT_REPO);
1203 		goto done;
1204 	}
1205 	kill_auth_proc(client);
1206 
1207 	log_info("authenticated uid %d for repository %s",
1208 	    client->euid, repo->name);
1209 
1210 	err = start_session_child(client, repo, gotd.argv0,
1211 	    gotd.confpath, gotd.daemonize, gotd.verbosity);
1212 	if (err)
1213 		goto done;
1214 done:
1215 	if (err)
1216 		log_warnx("uid %d: %s", client->euid, err->msg);
1217 
1218 	/* We might have killed the auth process by now. */
1219 	if (client->auth != NULL) {
1220 		if (!shut) {
1221 			gotd_imsg_event_add(iev);
1222 		} else {
1223 			/* This pipe is dead. Remove its event handler */
1224 			event_del(&iev->ev);
1225 		}
1226 	}
1227 }
1228 
1229 static const struct got_error *
1230 connect_session(struct gotd_client *client)
1231 {
1232 	const struct got_error *err = NULL;
1233 	struct gotd_imsg_connect iconnect;
1234 	int s;
1235 
1236 	memset(&iconnect, 0, sizeof(iconnect));
1237 
1238 	s = dup(client->fd);
1239 	if (s == -1)
1240 		return got_error_from_errno("dup");
1241 
1242 	iconnect.client_id = client->id;
1243 	iconnect.euid = client->euid;
1244 	iconnect.egid = client->egid;
1245 
1246 	if (gotd_imsg_compose_event(&client->session->iev, GOTD_IMSG_CONNECT,
1247 	    PROC_GOTD, s, &iconnect, sizeof(iconnect)) == -1) {
1248 		err = got_error_from_errno("imsg compose CONNECT");
1249 		close(s);
1250 		return err;
1251 	}
1252 
1253 	/*
1254 	 * We are no longer interested in messages from this client.
1255 	 * Further client requests will be handled by the session process.
1256 	 */
1257 	msgbuf_clear(&client->iev.ibuf.w);
1258 	imsg_clear(&client->iev.ibuf);
1259 	event_del(&client->iev.ev);
1260 	client->fd = -1; /* will be closed via copy in client->iev.ibuf.fd */
1261 
1262 	return NULL;
1263 }
1264 
1265 static void
1266 gotd_dispatch_client_session(int fd, short event, void *arg)
1267 {
1268 	struct gotd_imsgev *iev = arg;
1269 	struct imsgbuf *ibuf = &iev->ibuf;
1270 	struct gotd_child_proc *proc = NULL;
1271 	struct gotd_client *client = NULL;
1272 	ssize_t n;
1273 	int shut = 0;
1274 	struct imsg imsg;
1275 
1276 	client = find_client_by_proc_fd(fd);
1277 	if (client == NULL) {
1278 		/* Can happen during process teardown. */
1279 		warnx("cannot find client for fd %d", fd);
1280 		shut = 1;
1281 		goto done;
1282 	}
1283 
1284 	if (event & EV_READ) {
1285 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
1286 			fatal("imsg_read error");
1287 		if (n == 0) {
1288 			/* Connection closed. */
1289 			shut = 1;
1290 			goto done;
1291 		}
1292 	}
1293 
1294 	if (event & EV_WRITE) {
1295 		n = msgbuf_write(&ibuf->w);
1296 		if (n == -1 && errno != EAGAIN)
1297 			fatal("msgbuf_write");
1298 		if (n == 0) {
1299 			/* Connection closed. */
1300 			shut = 1;
1301 			goto done;
1302 		}
1303 	}
1304 
1305 	proc = client->session;
1306 	if (proc == NULL)
1307 		fatalx("cannot find session child process for fd %d", fd);
1308 
1309 	for (;;) {
1310 		const struct got_error *err = NULL;
1311 		uint32_t client_id = 0;
1312 		int do_disconnect = 0, do_start_repo_child = 0;
1313 
1314 		if ((n = imsg_get(ibuf, &imsg)) == -1)
1315 			fatal("%s: imsg_get error", __func__);
1316 		if (n == 0)	/* No more messages. */
1317 			break;
1318 
1319 		switch (imsg.hdr.type) {
1320 		case GOTD_IMSG_ERROR:
1321 			do_disconnect = 1;
1322 			err = gotd_imsg_recv_error(&client_id, &imsg);
1323 			break;
1324 		case GOTD_IMSG_CLIENT_SESSION_READY:
1325 			if (client->state != GOTD_CLIENT_STATE_ACCESS_GRANTED) {
1326 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1327 				break;
1328 			}
1329 			do_start_repo_child = 1;
1330 			break;
1331 		case GOTD_IMSG_DISCONNECT:
1332 			do_disconnect = 1;
1333 			break;
1334 		default:
1335 			log_debug("unexpected imsg %d", imsg.hdr.type);
1336 			break;
1337 		}
1338 
1339 		if (!verify_imsg_src(client, proc, &imsg)) {
1340 			log_debug("dropping imsg type %d from PID %d",
1341 			    imsg.hdr.type, proc->pid);
1342 			imsg_free(&imsg);
1343 			continue;
1344 		}
1345 		if (err)
1346 			log_warnx("uid %d: %s", client->euid, err->msg);
1347 
1348 		if (do_start_repo_child) {
1349 			struct gotd_repo *repo;
1350 			const char *name = client->session->repo_name;
1351 
1352 			repo = gotd_find_repo_by_name(name, &gotd);
1353 			if (repo != NULL) {
1354 				enum gotd_procid proc_type;
1355 
1356 				if (client->required_auth & GOTD_AUTH_WRITE)
1357 					proc_type = PROC_REPO_WRITE;
1358 				else
1359 					proc_type = PROC_REPO_READ;
1360 
1361 				err = start_repo_child(client, proc_type, repo,
1362 				    gotd.argv0, gotd.confpath, gotd.daemonize,
1363 				    gotd.verbosity);
1364 			} else
1365 				err = got_error(GOT_ERR_NOT_GIT_REPO);
1366 
1367 			if (err) {
1368 				log_warnx("uid %d: %s", client->euid, err->msg);
1369 				do_disconnect = 1;
1370 			}
1371 		}
1372 
1373 		if (do_disconnect) {
1374 			if (err)
1375 				disconnect_on_error(client, err);
1376 			else
1377 				disconnect(client);
1378 		}
1379 
1380 		imsg_free(&imsg);
1381 	}
1382 done:
1383 	if (!shut) {
1384 		gotd_imsg_event_add(iev);
1385 	} else {
1386 		/* This pipe is dead. Remove its event handler */
1387 		event_del(&iev->ev);
1388 		disconnect(client);
1389 	}
1390 }
1391 
1392 static void
1393 gotd_dispatch_repo_child(int fd, short event, void *arg)
1394 {
1395 	struct gotd_imsgev *iev = arg;
1396 	struct imsgbuf *ibuf = &iev->ibuf;
1397 	struct gotd_child_proc *proc = NULL;
1398 	struct gotd_client *client;
1399 	ssize_t n;
1400 	int shut = 0;
1401 	struct imsg imsg;
1402 
1403 	client = find_client_by_proc_fd(fd);
1404 	if (client == NULL) {
1405 		/* Can happen during process teardown. */
1406 		warnx("cannot find client for fd %d", fd);
1407 		shut = 1;
1408 		goto done;
1409 	}
1410 
1411 	if (event & EV_READ) {
1412 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
1413 			fatal("imsg_read error");
1414 		if (n == 0) {
1415 			/* Connection closed. */
1416 			shut = 1;
1417 			goto done;
1418 		}
1419 	}
1420 
1421 	if (event & EV_WRITE) {
1422 		n = msgbuf_write(&ibuf->w);
1423 		if (n == -1 && errno != EAGAIN)
1424 			fatal("msgbuf_write");
1425 		if (n == 0) {
1426 			/* Connection closed. */
1427 			shut = 1;
1428 			goto done;
1429 		}
1430 	}
1431 
1432 	proc = client->repo;
1433 	if (proc == NULL)
1434 		fatalx("cannot find child process for fd %d", fd);
1435 
1436 	for (;;) {
1437 		const struct got_error *err = NULL;
1438 		uint32_t client_id = 0;
1439 		int do_disconnect = 0;
1440 
1441 		if ((n = imsg_get(ibuf, &imsg)) == -1)
1442 			fatal("%s: imsg_get error", __func__);
1443 		if (n == 0)	/* No more messages. */
1444 			break;
1445 
1446 		switch (imsg.hdr.type) {
1447 		case GOTD_IMSG_ERROR:
1448 			do_disconnect = 1;
1449 			err = gotd_imsg_recv_error(&client_id, &imsg);
1450 			break;
1451 		case GOTD_IMSG_REPO_CHILD_READY:
1452 			err = connect_session(client);
1453 			if (err)
1454 				break;
1455 			err = connect_repo_child(client, proc);
1456 			break;
1457 		default:
1458 			log_debug("unexpected imsg %d", imsg.hdr.type);
1459 			break;
1460 		}
1461 
1462 		if (!verify_imsg_src(client, proc, &imsg)) {
1463 			log_debug("dropping imsg type %d from PID %d",
1464 			    imsg.hdr.type, proc->pid);
1465 			imsg_free(&imsg);
1466 			continue;
1467 		}
1468 		if (err)
1469 			log_warnx("uid %d: %s", client->euid, err->msg);
1470 
1471 		if (do_disconnect) {
1472 			if (err)
1473 				disconnect_on_error(client, err);
1474 			else
1475 				disconnect(client);
1476 		}
1477 
1478 		imsg_free(&imsg);
1479 	}
1480 done:
1481 	if (!shut) {
1482 		gotd_imsg_event_add(iev);
1483 	} else {
1484 		/* This pipe is dead. Remove its event handler */
1485 		event_del(&iev->ev);
1486 		disconnect(client);
1487 	}
1488 }
1489 
1490 static pid_t
1491 start_child(enum gotd_procid proc_id, const char *repo_path,
1492     char *argv0, const char *confpath, int fd, int daemonize, int verbosity)
1493 {
1494 	char	*argv[11];
1495 	int	 argc = 0;
1496 	pid_t	 pid;
1497 
1498 	switch (pid = fork()) {
1499 	case -1:
1500 		fatal("cannot fork");
1501 	case 0:
1502 		break;
1503 	default:
1504 		close(fd);
1505 		return pid;
1506 	}
1507 
1508 	if (fd != GOTD_FILENO_MSG_PIPE) {
1509 		if (dup2(fd, GOTD_FILENO_MSG_PIPE) == -1)
1510 			fatal("cannot setup imsg fd");
1511 	} else if (fcntl(fd, F_SETFD, 0) == -1)
1512 		fatal("cannot setup imsg fd");
1513 
1514 	argv[argc++] = argv0;
1515 	switch (proc_id) {
1516 	case PROC_LISTEN:
1517 		argv[argc++] = (char *)"-L";
1518 		break;
1519 	case PROC_AUTH:
1520 		argv[argc++] = (char *)"-A";
1521 		break;
1522 	case PROC_SESSION_READ:
1523 		argv[argc++] = (char *)"-s";
1524 		break;
1525 	case PROC_SESSION_WRITE:
1526 		argv[argc++] = (char *)"-S";
1527 		break;
1528 	case PROC_REPO_READ:
1529 		argv[argc++] = (char *)"-R";
1530 		break;
1531 	case PROC_REPO_WRITE:
1532 		argv[argc++] = (char *)"-W";
1533 		break;
1534 	default:
1535 		fatalx("invalid process id %d", proc_id);
1536 	}
1537 
1538 	argv[argc++] = (char *)"-f";
1539 	argv[argc++] = (char *)confpath;
1540 
1541 	if (repo_path) {
1542 		argv[argc++] = (char *)"-P";
1543 		argv[argc++] = (char *)repo_path;
1544 	}
1545 
1546 	if (!daemonize)
1547 		argv[argc++] = (char *)"-d";
1548 	if (verbosity > 0)
1549 		argv[argc++] = (char *)"-v";
1550 	if (verbosity > 1)
1551 		argv[argc++] = (char *)"-v";
1552 	argv[argc++] = NULL;
1553 
1554 	execvp(argv0, argv);
1555 	fatal("execvp");
1556 }
1557 
1558 static void
1559 start_listener(char *argv0, const char *confpath, int daemonize, int verbosity)
1560 {
1561 	struct gotd_child_proc *proc;
1562 
1563 	proc = calloc(1, sizeof(*proc));
1564 	if (proc == NULL)
1565 		fatal("calloc");
1566 
1567 	TAILQ_INSERT_HEAD(&procs, proc, entry);
1568 
1569 	/* proc->tmo is initialized in main() after event_init() */
1570 
1571 	proc->type = PROC_LISTEN;
1572 
1573 	if (socketpair(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK,
1574 	    PF_UNSPEC, proc->pipe) == -1)
1575 		fatal("socketpair");
1576 
1577 	proc->pid = start_child(proc->type, NULL, argv0, confpath,
1578 	    proc->pipe[1], daemonize, verbosity);
1579 	imsg_init(&proc->iev.ibuf, proc->pipe[0]);
1580 	proc->iev.handler = gotd_dispatch_listener;
1581 	proc->iev.events = EV_READ;
1582 	proc->iev.handler_arg = NULL;
1583 
1584 	gotd.listen_proc = proc;
1585 }
1586 
1587 static const struct got_error *
1588 start_session_child(struct gotd_client *client, struct gotd_repo *repo,
1589     char *argv0, const char *confpath, int daemonize, int verbosity)
1590 {
1591 	struct gotd_child_proc *proc;
1592 
1593 	proc = calloc(1, sizeof(*proc));
1594 	if (proc == NULL)
1595 		return got_error_from_errno("calloc");
1596 
1597 	TAILQ_INSERT_HEAD(&procs, proc, entry);
1598 	evtimer_set(&proc->tmo, kill_proc_timeout, proc);
1599 
1600 	if (client_is_reading(client))
1601 		proc->type = PROC_SESSION_READ;
1602 	else
1603 		proc->type = PROC_SESSION_WRITE;
1604 	if (strlcpy(proc->repo_name, repo->name,
1605 	    sizeof(proc->repo_name)) >= sizeof(proc->repo_name))
1606 		fatalx("repository name too long: %s", repo->name);
1607 	log_debug("starting client uid %d session for repository %s",
1608 	    client->euid, repo->name);
1609 	if (strlcpy(proc->repo_path, repo->path, sizeof(proc->repo_path)) >=
1610 	    sizeof(proc->repo_path))
1611 		fatalx("repository path too long: %s", repo->path);
1612 	if (socketpair(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK,
1613 	    PF_UNSPEC, proc->pipe) == -1)
1614 		fatal("socketpair");
1615 	proc->pid = start_child(proc->type, proc->repo_path, argv0,
1616 	    confpath, proc->pipe[1], daemonize, verbosity);
1617 	imsg_init(&proc->iev.ibuf, proc->pipe[0]);
1618 	log_debug("proc %s %s is on fd %d",
1619 	    gotd_proc_names[proc->type], proc->repo_path,
1620 	    proc->pipe[0]);
1621 	proc->iev.handler = gotd_dispatch_client_session;
1622 	proc->iev.events = EV_READ;
1623 	proc->iev.handler_arg = NULL;
1624 	event_set(&proc->iev.ev, proc->iev.ibuf.fd, EV_READ,
1625 	    gotd_dispatch_client_session, &proc->iev);
1626 	gotd_imsg_event_add(&proc->iev);
1627 
1628 	client->session = proc;
1629 	return NULL;
1630 }
1631 
1632 static const struct got_error *
1633 start_repo_child(struct gotd_client *client, enum gotd_procid proc_type,
1634     struct gotd_repo *repo, char *argv0, const char *confpath,
1635     int daemonize, int verbosity)
1636 {
1637 	struct gotd_child_proc *proc;
1638 
1639 	if (proc_type != PROC_REPO_READ && proc_type != PROC_REPO_WRITE)
1640 		return got_error_msg(GOT_ERR_NOT_IMPL, "bad process type");
1641 
1642 	proc = calloc(1, sizeof(*proc));
1643 	if (proc == NULL)
1644 		return got_error_from_errno("calloc");
1645 
1646 	TAILQ_INSERT_HEAD(&procs, proc, entry);
1647 	evtimer_set(&proc->tmo, kill_proc_timeout, proc);
1648 
1649 	proc->type = proc_type;
1650 	if (strlcpy(proc->repo_name, repo->name,
1651 	    sizeof(proc->repo_name)) >= sizeof(proc->repo_name))
1652 		fatalx("repository name too long: %s", repo->name);
1653 	log_debug("starting %s for repository %s",
1654 	    proc->type == PROC_REPO_READ ? "reader" : "writer", repo->name);
1655 	if (strlcpy(proc->repo_path, repo->path, sizeof(proc->repo_path)) >=
1656 	    sizeof(proc->repo_path))
1657 		fatalx("repository path too long: %s", repo->path);
1658 	if (socketpair(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK,
1659 	    PF_UNSPEC, proc->pipe) == -1)
1660 		fatal("socketpair");
1661 	proc->pid = start_child(proc->type, proc->repo_path, argv0,
1662 	    confpath, proc->pipe[1], daemonize, verbosity);
1663 	imsg_init(&proc->iev.ibuf, proc->pipe[0]);
1664 	log_debug("proc %s %s is on fd %d",
1665 	    gotd_proc_names[proc->type], proc->repo_path,
1666 	    proc->pipe[0]);
1667 	proc->iev.handler = gotd_dispatch_repo_child;
1668 	proc->iev.events = EV_READ;
1669 	proc->iev.handler_arg = NULL;
1670 	event_set(&proc->iev.ev, proc->iev.ibuf.fd, EV_READ,
1671 	    gotd_dispatch_repo_child, &proc->iev);
1672 	gotd_imsg_event_add(&proc->iev);
1673 
1674 	client->repo = proc;
1675 	return NULL;
1676 }
1677 
1678 static const struct got_error *
1679 start_auth_child(struct gotd_client *client, int required_auth,
1680     struct gotd_repo *repo, char *argv0, const char *confpath,
1681     int daemonize, int verbosity)
1682 {
1683 	const struct got_error *err = NULL;
1684 	struct gotd_child_proc *proc;
1685 	struct gotd_imsg_auth iauth;
1686 	int fd;
1687 
1688 	memset(&iauth, 0, sizeof(iauth));
1689 
1690 	fd = dup(client->fd);
1691 	if (fd == -1)
1692 		return got_error_from_errno("dup");
1693 
1694 	proc = calloc(1, sizeof(*proc));
1695 	if (proc == NULL) {
1696 		err = got_error_from_errno("calloc");
1697 		close(fd);
1698 		return err;
1699 	}
1700 
1701 	TAILQ_INSERT_HEAD(&procs, proc, entry);
1702 	evtimer_set(&proc->tmo, kill_proc_timeout, proc);
1703 
1704 	proc->type = PROC_AUTH;
1705 	if (strlcpy(proc->repo_name, repo->name,
1706 	    sizeof(proc->repo_name)) >= sizeof(proc->repo_name))
1707 		fatalx("repository name too long: %s", repo->name);
1708 	log_debug("starting auth for uid %d repository %s",
1709 	    client->euid, repo->name);
1710 	if (strlcpy(proc->repo_path, repo->path, sizeof(proc->repo_path)) >=
1711 	    sizeof(proc->repo_path))
1712 		fatalx("repository path too long: %s", repo->path);
1713 	if (socketpair(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK,
1714 	    PF_UNSPEC, proc->pipe) == -1)
1715 		fatal("socketpair");
1716 	proc->pid = start_child(proc->type, proc->repo_path, argv0,
1717 	    confpath, proc->pipe[1], daemonize, verbosity);
1718 	imsg_init(&proc->iev.ibuf, proc->pipe[0]);
1719 	log_debug("proc %s %s is on fd %d",
1720 	    gotd_proc_names[proc->type], proc->repo_path,
1721 	    proc->pipe[0]);
1722 	proc->iev.handler = gotd_dispatch_auth_child;
1723 	proc->iev.events = EV_READ;
1724 	proc->iev.handler_arg = NULL;
1725 	event_set(&proc->iev.ev, proc->iev.ibuf.fd, EV_READ,
1726 	    gotd_dispatch_auth_child, &proc->iev);
1727 	gotd_imsg_event_add(&proc->iev);
1728 
1729 	iauth.euid = client->euid;
1730 	iauth.egid = client->egid;
1731 	iauth.required_auth = required_auth;
1732 	iauth.client_id = client->id;
1733 	if (gotd_imsg_compose_event(&proc->iev, GOTD_IMSG_AUTHENTICATE,
1734 	    PROC_GOTD, fd, &iauth, sizeof(iauth)) == -1) {
1735 		log_warn("imsg compose AUTHENTICATE");
1736 		close(fd);
1737 		/* Let the auth_timeout handler tidy up. */
1738 	}
1739 
1740 	client->auth = proc;
1741 	client->required_auth = required_auth;
1742 	return NULL;
1743 }
1744 
1745 static void
1746 apply_unveil_repo_readonly(const char *repo_path, int need_tmpdir)
1747 {
1748 	if (need_tmpdir) {
1749 		if (unveil(GOT_TMPDIR_STR, "rwc") == -1)
1750 			fatal("unveil %s", GOT_TMPDIR_STR);
1751 	}
1752 
1753 	if (unveil(repo_path, "r") == -1)
1754 		fatal("unveil %s", repo_path);
1755 
1756 	if (unveil(NULL, NULL) == -1)
1757 		fatal("unveil");
1758 }
1759 
1760 static void
1761 apply_unveil_repo_readwrite(const char *repo_path)
1762 {
1763 	if (unveil(repo_path, "rwc") == -1)
1764 		fatal("unveil %s", repo_path);
1765 
1766 	if (unveil(GOT_TMPDIR_STR, "rwc") == -1)
1767 		fatal("unveil %s", GOT_TMPDIR_STR);
1768 
1769 	if (unveil(NULL, NULL) == -1)
1770 		fatal("unveil");
1771 }
1772 
1773 static void
1774 apply_unveil_none(void)
1775 {
1776 	if (unveil("/", "") == -1)
1777 		fatal("unveil");
1778 
1779 	if (unveil(NULL, NULL) == -1)
1780 		fatal("unveil");
1781 }
1782 
1783 static void
1784 apply_unveil_selfexec(void)
1785 {
1786 	if (unveil(gotd.argv0, "x") == -1)
1787 		fatal("unveil %s", gotd.argv0);
1788 
1789 	if (unveil(NULL, NULL) == -1)
1790 		fatal("unveil");
1791 }
1792 
1793 int
1794 main(int argc, char **argv)
1795 {
1796 	const struct got_error *error = NULL;
1797 	int ch, fd = -1, daemonize = 1, verbosity = 0, noaction = 0;
1798 	const char *confpath = GOTD_CONF_PATH;
1799 	char *argv0 = argv[0];
1800 	char title[2048];
1801 	struct passwd *pw = NULL;
1802 	char *repo_path = NULL;
1803 	enum gotd_procid proc_id = PROC_GOTD;
1804 	struct event evsigint, evsigterm, evsighup, evsigusr1, evsigchld;
1805 	int *pack_fds = NULL, *temp_fds = NULL;
1806 	struct gotd_repo *repo = NULL;
1807 
1808 	TAILQ_INIT(&procs);
1809 
1810 	log_init(1, LOG_DAEMON); /* Log to stderr until daemonized. */
1811 
1812 	while ((ch = getopt(argc, argv, "Adf:LnP:RsSvW")) != -1) {
1813 		switch (ch) {
1814 		case 'A':
1815 			proc_id = PROC_AUTH;
1816 			break;
1817 		case 'd':
1818 			daemonize = 0;
1819 			break;
1820 		case 'f':
1821 			confpath = optarg;
1822 			break;
1823 		case 'L':
1824 			proc_id = PROC_LISTEN;
1825 			break;
1826 		case 'n':
1827 			noaction = 1;
1828 			break;
1829 		case 'P':
1830 			repo_path = realpath(optarg, NULL);
1831 			if (repo_path == NULL)
1832 				fatal("realpath '%s'", optarg);
1833 			break;
1834 		case 'R':
1835 			proc_id = PROC_REPO_READ;
1836 			break;
1837 		case 's':
1838 			proc_id = PROC_SESSION_READ;
1839 			break;
1840 		case 'S':
1841 			proc_id = PROC_SESSION_WRITE;
1842 			break;
1843 		case 'v':
1844 			if (verbosity < 3)
1845 				verbosity++;
1846 			break;
1847 		case 'W':
1848 			proc_id = PROC_REPO_WRITE;
1849 			break;
1850 		default:
1851 			usage();
1852 		}
1853 	}
1854 
1855 	argc -= optind;
1856 	argv += optind;
1857 
1858 	if (argc != 0)
1859 		usage();
1860 
1861 	if (geteuid() && (proc_id == PROC_GOTD || proc_id == PROC_LISTEN))
1862 		fatalx("need root privileges");
1863 
1864 	if (parse_config(confpath, proc_id, &gotd) != 0)
1865 		return 1;
1866 
1867 	pw = getpwnam(gotd.user_name);
1868 	if (pw == NULL)
1869 		fatalx("user %s not found", gotd.user_name);
1870 
1871 	if (pw->pw_uid == 0)
1872 		fatalx("cannot run %s as the superuser", getprogname());
1873 
1874 	if (noaction) {
1875 		fprintf(stderr, "configuration OK\n");
1876 		return 0;
1877 	}
1878 
1879 	gotd.argv0 = argv0;
1880 	gotd.daemonize = daemonize;
1881 	gotd.verbosity = verbosity;
1882 	gotd.confpath = confpath;
1883 
1884 	/* Require an absolute path in argv[0] for reliable re-exec. */
1885 	if (!got_path_is_absolute(argv0))
1886 		fatalx("bad path \"%s\": must be an absolute path", argv0);
1887 
1888 	log_init(daemonize ? 0 : 1, LOG_DAEMON);
1889 	log_setverbose(verbosity);
1890 
1891 	if (proc_id == PROC_GOTD) {
1892 		snprintf(title, sizeof(title), "%s", gotd_proc_names[proc_id]);
1893 		arc4random_buf(&clients_hash_key, sizeof(clients_hash_key));
1894 		if (daemonize && daemon(1, 0) == -1)
1895 			fatal("daemon");
1896 		gotd.pid = getpid();
1897 		start_listener(argv0, confpath, daemonize, verbosity);
1898 	} else if (proc_id == PROC_LISTEN) {
1899 		snprintf(title, sizeof(title), "%s", gotd_proc_names[proc_id]);
1900 		if (verbosity) {
1901 			log_info("socket: %s", gotd.unix_socket_path);
1902 			log_info("user: %s", pw->pw_name);
1903 		}
1904 
1905 		fd = unix_socket_listen(gotd.unix_socket_path, pw->pw_uid,
1906 		    pw->pw_gid);
1907 		if (fd == -1) {
1908 			fatal("cannot listen on unix socket %s",
1909 			    gotd.unix_socket_path);
1910 		}
1911 	} else if (proc_id == PROC_AUTH) {
1912 		snprintf(title, sizeof(title), "%s %s",
1913 		    gotd_proc_names[proc_id], repo_path);
1914 	} else if (proc_id == PROC_REPO_READ || proc_id == PROC_REPO_WRITE ||
1915 	    proc_id == PROC_SESSION_READ || proc_id == PROC_SESSION_WRITE) {
1916 		error = got_repo_pack_fds_open(&pack_fds);
1917 		if (error != NULL)
1918 			fatalx("cannot open pack tempfiles: %s", error->msg);
1919 		error = got_repo_temp_fds_open(&temp_fds);
1920 		if (error != NULL)
1921 			fatalx("cannot open pack tempfiles: %s", error->msg);
1922 		if (repo_path == NULL)
1923 			fatalx("repository path not specified");
1924 		snprintf(title, sizeof(title), "%s %s",
1925 		    gotd_proc_names[proc_id], repo_path);
1926 	} else
1927 		fatal("invalid process id %d", proc_id);
1928 
1929 	setproctitle("%s", title);
1930 	log_procinit(title);
1931 
1932 	/* Drop root privileges. */
1933 	if (setgid(pw->pw_gid) == -1)
1934 		fatal("setgid %d failed", pw->pw_gid);
1935 	if (setuid(pw->pw_uid) == -1)
1936 		fatal("setuid %d failed", pw->pw_uid);
1937 
1938 	event_init();
1939 
1940 	switch (proc_id) {
1941 	case PROC_GOTD:
1942 #ifndef PROFILE
1943 		/* "exec" promise will be limited to argv[0] via unveil(2). */
1944 		if (pledge("stdio proc exec sendfd recvfd unveil", NULL) == -1)
1945 			err(1, "pledge");
1946 #endif
1947 		break;
1948 	case PROC_LISTEN:
1949 #ifndef PROFILE
1950 		if (pledge("stdio sendfd unix unveil", NULL) == -1)
1951 			err(1, "pledge");
1952 #endif
1953 		/*
1954 		 * Ensure that AF_UNIX bind(2) cannot be used with any other
1955 		 * sockets by revoking all filesystem access via unveil(2).
1956 		 */
1957 		apply_unveil_none();
1958 
1959 		listen_main(title, fd, gotd.connection_limits,
1960 		    gotd.nconnection_limits);
1961 		/* NOTREACHED */
1962 		break;
1963 	case PROC_AUTH:
1964 #ifndef PROFILE
1965 		if (pledge("stdio getpw recvfd unix unveil", NULL) == -1)
1966 			err(1, "pledge");
1967 #endif
1968 		/*
1969 		 * We need the "unix" pledge promise for getpeername(2) only.
1970 		 * Ensure that AF_UNIX bind(2) cannot be used by revoking all
1971 		 * filesystem access via unveil(2). Access to password database
1972 		 * files will still work since "getpw" bypasses unveil(2).
1973 		 */
1974 		apply_unveil_none();
1975 
1976 		auth_main(title, &gotd.repos, repo_path);
1977 		/* NOTREACHED */
1978 		break;
1979 	case PROC_SESSION_READ:
1980 	case PROC_SESSION_WRITE:
1981 #ifndef PROFILE
1982 		/*
1983 		 * The "recvfd" promise is only needed during setup and
1984 		 * will be removed in a later pledge(2) call.
1985 		 */
1986 		if (pledge("stdio rpath wpath cpath recvfd sendfd fattr flock "
1987 		    "unveil", NULL) == -1)
1988 			err(1, "pledge");
1989 #endif
1990 		if (proc_id == PROC_SESSION_READ)
1991 			apply_unveil_repo_readonly(repo_path, 1);
1992 		else
1993 			apply_unveil_repo_readwrite(repo_path);
1994 		session_main(title, repo_path, pack_fds, temp_fds,
1995 		    &gotd.request_timeout, proc_id);
1996 		/* NOTREACHED */
1997 		break;
1998 	case PROC_REPO_READ:
1999 #ifndef PROFILE
2000 		if (pledge("stdio rpath recvfd unveil", NULL) == -1)
2001 			err(1, "pledge");
2002 #endif
2003 		apply_unveil_repo_readonly(repo_path, 0);
2004 		repo_read_main(title, repo_path, pack_fds, temp_fds);
2005 		/* NOTREACHED */
2006 		exit(0);
2007 	case PROC_REPO_WRITE:
2008 #ifndef PROFILE
2009 		if (pledge("stdio rpath recvfd unveil", NULL) == -1)
2010 			err(1, "pledge");
2011 #endif
2012 		apply_unveil_repo_readonly(repo_path, 0);
2013 		repo = gotd_find_repo_by_path(repo_path, &gotd);
2014 		if (repo == NULL)
2015 			fatalx("no repository for path %s", repo_path);
2016 		repo_write_main(title, repo_path, pack_fds, temp_fds,
2017 		    &repo->protected_tag_namespaces,
2018 		    &repo->protected_branch_namespaces,
2019 		    &repo->protected_branches);
2020 		/* NOTREACHED */
2021 		exit(0);
2022 	default:
2023 		fatal("invalid process id %d", proc_id);
2024 	}
2025 
2026 	if (proc_id != PROC_GOTD)
2027 		fatal("invalid process id %d", proc_id);
2028 
2029 	evtimer_set(&gotd.listen_proc->tmo, kill_proc_timeout,
2030 	    gotd.listen_proc);
2031 
2032 	apply_unveil_selfexec();
2033 
2034 	signal_set(&evsigint, SIGINT, gotd_sighdlr, NULL);
2035 	signal_set(&evsigterm, SIGTERM, gotd_sighdlr, NULL);
2036 	signal_set(&evsighup, SIGHUP, gotd_sighdlr, NULL);
2037 	signal_set(&evsigusr1, SIGUSR1, gotd_sighdlr, NULL);
2038 	signal_set(&evsigchld, SIGCHLD, gotd_sighdlr, NULL);
2039 	signal(SIGPIPE, SIG_IGN);
2040 
2041 	signal_add(&evsigint, NULL);
2042 	signal_add(&evsigterm, NULL);
2043 	signal_add(&evsighup, NULL);
2044 	signal_add(&evsigusr1, NULL);
2045 	signal_add(&evsigchld, NULL);
2046 
2047 	gotd_imsg_event_add(&gotd.listen_proc->iev);
2048 
2049 	event_dispatch();
2050 
2051 	free(repo_path);
2052 	gotd_shutdown();
2053 
2054 	return 0;
2055 }