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Date:: Fri Dec 30 17:02:44 2022 UTC
Message:: fmt
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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 <grp.h>
33 #include <imsg.h>
34 #include <sha1.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_sha1.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 "repo_read.h"
64 #include "repo_write.h"
65 
66 #ifndef nitems
67 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
68 #endif
69 
70 struct gotd_client {
71 	STAILQ_ENTRY(gotd_client)	 entry;
72 	enum gotd_client_state		 state;
73 	struct gotd_client_capability	*capabilities;
74 	size_t				 ncapa_alloc;
75 	size_t				 ncapabilities;
76 	uint32_t			 id;
77 	int				 fd;
78 	int				 delta_cache_fd;
79 	struct gotd_imsgev		 iev;
80 	struct event			 tmo;
81 	uid_t				 euid;
82 	gid_t				 egid;
83 	struct gotd_child_proc		*repo_read;
84 	struct gotd_child_proc		*repo_write;
85 	struct gotd_child_proc		*auth;
86 	int				 required_auth;
87 	char				*packfile_path;
88 	char				*packidx_path;
89 	int				 nref_updates;
90 };
91 STAILQ_HEAD(gotd_clients, gotd_client);
92 
93 static struct gotd_clients gotd_clients[GOTD_CLIENT_TABLE_SIZE];
94 static SIPHASH_KEY clients_hash_key;
95 volatile int client_cnt;
96 static struct timeval timeout = { 3600, 0 };
97 static struct timeval auth_timeout = { 5, 0 };
98 static struct gotd gotd;
99 
100 void gotd_sighdlr(int sig, short event, void *arg);
101 static void gotd_shutdown(void);
102 static const struct got_error *start_repo_child(struct gotd_client *,
103     enum gotd_procid, struct gotd_repo *, char *, const char *, int, int);
104 static const struct got_error *start_auth_child(struct gotd_client *, int,
105     struct gotd_repo *, char *, const char *, int, int);
106 static void kill_proc(struct gotd_child_proc *, int);
107 
108 __dead static void
109 usage()
110 {
111 	fprintf(stderr, "usage: %s [-dv] [-f config-file]\n", getprogname());
112 	exit(1);
113 }
114 
115 static int
116 unix_socket_listen(const char *unix_socket_path, uid_t uid, gid_t gid)
117 {
118 	struct sockaddr_un sun;
119 	int fd = -1;
120 	mode_t old_umask, mode;
121 
122 	fd = socket(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK| SOCK_CLOEXEC, 0);
123 	if (fd == -1) {
124 		log_warn("socket");
125 		return -1;
126 	}
127 
128 	sun.sun_family = AF_UNIX;
129 	if (strlcpy(sun.sun_path, unix_socket_path,
130 	    sizeof(sun.sun_path)) >= sizeof(sun.sun_path)) {
131 		log_warnx("%s: name too long", unix_socket_path);
132 		close(fd);
133 		return -1;
134 	}
135 
136 	if (unlink(unix_socket_path) == -1) {
137 		if (errno != ENOENT) {
138 			log_warn("unlink %s", unix_socket_path);
139 			close(fd);
140 			return -1;
141 		}
142 	}
143 
144 	old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
145 	mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP;
146 
147 	if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
148 		log_warn("bind: %s", unix_socket_path);
149 		close(fd);
150 		umask(old_umask);
151 		return -1;
152 	}
153 
154 	umask(old_umask);
155 
156 	if (chmod(unix_socket_path, mode) == -1) {
157 		log_warn("chmod %o %s", mode, unix_socket_path);
158 		close(fd);
159 		unlink(unix_socket_path);
160 		return -1;
161 	}
162 
163 	if (chown(unix_socket_path, uid, gid) == -1) {
164 		log_warn("chown %s uid=%d gid=%d", unix_socket_path, uid, gid);
165 		close(fd);
166 		unlink(unix_socket_path);
167 		return -1;
168 	}
169 
170 	if (listen(fd, GOTD_UNIX_SOCKET_BACKLOG) == -1) {
171 		log_warn("listen");
172 		close(fd);
173 		unlink(unix_socket_path);
174 		return -1;
175 	}
176 
177 	return fd;
178 }
179 
180 static struct group *
181 match_group(gid_t *groups, int ngroups, const char *unix_group_name)
182 {
183 	struct group *gr;
184 	int i;
185 
186 	for (i = 0; i < ngroups; i++) {
187 		gr = getgrgid(groups[i]);
188 		if (gr == NULL) {
189 			log_warn("getgrgid %d", groups[i]);
190 			continue;
191 		}
192 		if (strcmp(gr->gr_name, unix_group_name) == 0)
193 			return gr;
194 	}
195 
196 	return NULL;
197 }
198 
199 static uint64_t
200 client_hash(uint32_t client_id)
201 {
202 	return SipHash24(&clients_hash_key, &client_id, sizeof(client_id));
203 }
204 
205 static void
206 add_client(struct gotd_client *client)
207 {
208 	uint64_t slot = client_hash(client->id) % nitems(gotd_clients);
209 	STAILQ_INSERT_HEAD(&gotd_clients[slot], client, entry);
210 	client_cnt++;
211 }
212 
213 static struct gotd_client *
214 find_client(uint32_t client_id)
215 {
216 	uint64_t slot;
217 	struct gotd_client *c;
218 
219 	slot = client_hash(client_id) % nitems(gotd_clients);
220 	STAILQ_FOREACH(c, &gotd_clients[slot], entry) {
221 		if (c->id == client_id)
222 			return c;
223 	}
224 
225 	return NULL;
226 }
227 
228 static struct gotd_child_proc *
229 get_client_proc(struct gotd_client *client)
230 {
231 	if (client->repo_read && client->repo_write) {
232 		fatalx("uid %d is reading and writing in the same session",
233 		    client->euid);
234 		/* NOTREACHED */
235 	}
236 
237 	if (client->repo_read)
238 		return client->repo_read;
239 	else if (client->repo_write)
240 		return client->repo_write;
241 
242 	return NULL;
243 }
244 
245 static struct gotd_client *
246 find_client_by_proc_fd(int fd)
247 {
248 	uint64_t slot;
249 
250 	for (slot = 0; slot < nitems(gotd_clients); slot++) {
251 		struct gotd_client *c;
252 
253 		STAILQ_FOREACH(c, &gotd_clients[slot], entry) {
254 			struct gotd_child_proc *proc = get_client_proc(c);
255 			if (proc && proc->iev.ibuf.fd == fd)
256 				return c;
257 			if (c->auth && c->auth->iev.ibuf.fd == fd)
258 				return c;
259 		}
260 	}
261 
262 	return NULL;
263 }
264 
265 static int
266 client_is_reading(struct gotd_client *client)
267 {
268 	return client->repo_read != NULL;
269 }
270 
271 static int
272 client_is_writing(struct gotd_client *client)
273 {
274 	return client->repo_write != NULL;
275 }
276 
277 static const struct got_error *
278 ensure_client_is_reading(struct gotd_client *client)
279 {
280 	if (!client_is_reading(client)) {
281 		return got_error_fmt(GOT_ERR_BAD_PACKET,
282 		    "uid %d made a read-request but is not reading from "
283 		    "a repository", client->euid);
284 	}
285 
286 	return NULL;
287 }
288 
289 static const struct got_error *
290 ensure_client_is_writing(struct gotd_client *client)
291 {
292 	if (!client_is_writing(client)) {
293 		return got_error_fmt(GOT_ERR_BAD_PACKET,
294 		    "uid %d made a write-request but is not writing to "
295 		    "a repository", client->euid);
296 	}
297 
298 	return NULL;
299 }
300 
301 static const struct got_error *
302 ensure_client_is_not_writing(struct gotd_client *client)
303 {
304 	if (client_is_writing(client)) {
305 		return got_error_fmt(GOT_ERR_BAD_PACKET,
306 		    "uid %d made a read-request but is writing to "
307 		    "a repository", client->euid);
308 	}
309 
310 	return NULL;
311 }
312 
313 static const struct got_error *
314 ensure_client_is_not_reading(struct gotd_client *client)
315 {
316 	if (client_is_reading(client)) {
317 		return got_error_fmt(GOT_ERR_BAD_PACKET,
318 		    "uid %d made a write-request but is reading from "
319 		    "a repository", client->euid);
320 	}
321 
322 	return NULL;
323 }
324 
325 static void
326 wait_for_child(pid_t child_pid)
327 {
328 	pid_t pid;
329 	int status;
330 
331 	log_debug("waiting for child PID %ld to terminate",
332 	    (long)child_pid);
333 
334 	do {
335 		pid = waitpid(child_pid, &status, WNOHANG);
336 		if (pid == -1) {
337 			if (errno != EINTR && errno != ECHILD)
338 				fatal("wait");
339 		} else if (WIFSIGNALED(status)) {
340 			log_warnx("child PID %ld terminated; signal %d",
341 			    (long)pid, WTERMSIG(status));
342 		}
343 	} while (pid != -1 || (pid == -1 && errno == EINTR));
344 }
345 
346 static void
347 kill_auth_proc(struct gotd_client *client)
348 {
349 	struct gotd_child_proc *proc;
350 
351 	if (client->auth == NULL)
352 		return;
353 
354 	proc = client->auth;
355 	client->auth = NULL;
356 
357 	event_del(&proc->iev.ev);
358 	msgbuf_clear(&proc->iev.ibuf.w);
359 	close(proc->iev.ibuf.fd);
360 	kill_proc(proc, 0);
361 	wait_for_child(proc->pid);
362 	free(proc);
363 }
364 
365 static void
366 disconnect(struct gotd_client *client)
367 {
368 	struct gotd_imsg_disconnect idisconnect;
369 	struct gotd_child_proc *proc = get_client_proc(client);
370 	struct gotd_child_proc *listen_proc = &gotd.listen_proc;
371 	uint64_t slot;
372 
373 	log_debug("uid %d: disconnecting", client->euid);
374 
375 	kill_auth_proc(client);
376 
377 	idisconnect.client_id = client->id;
378 	if (proc) {
379 		if (gotd_imsg_compose_event(&proc->iev,
380 		    GOTD_IMSG_DISCONNECT, PROC_GOTD, -1,
381 		    &idisconnect, sizeof(idisconnect)) == -1)
382 			log_warn("imsg compose DISCONNECT");
383 
384 		msgbuf_clear(&proc->iev.ibuf.w);
385 		close(proc->iev.ibuf.fd);
386 		kill_proc(proc, 0);
387 		wait_for_child(proc->pid);
388 		free(proc);
389 		proc = NULL;
390 	}
391 
392 	if (gotd_imsg_compose_event(&listen_proc->iev,
393 	    GOTD_IMSG_DISCONNECT, PROC_GOTD, -1,
394 	    &idisconnect, sizeof(idisconnect)) == -1)
395 		log_warn("imsg compose DISCONNECT");
396 
397 	slot = client_hash(client->id) % nitems(gotd_clients);
398 	STAILQ_REMOVE(&gotd_clients[slot], client, gotd_client, entry);
399 	imsg_clear(&client->iev.ibuf);
400 	event_del(&client->iev.ev);
401 	evtimer_del(&client->tmo);
402 	close(client->fd);
403 	if (client->delta_cache_fd != -1)
404 		close(client->delta_cache_fd);
405 	if (client->packfile_path) {
406 		if (unlink(client->packfile_path) == -1 && errno != ENOENT)
407 			log_warn("unlink %s: ", client->packfile_path);
408 		free(client->packfile_path);
409 	}
410 	if (client->packidx_path) {
411 		if (unlink(client->packidx_path) == -1 && errno != ENOENT)
412 			log_warn("unlink %s: ", client->packidx_path);
413 		free(client->packidx_path);
414 	}
415 	free(client->capabilities);
416 	free(client);
417 	client_cnt--;
418 }
419 
420 static void
421 disconnect_on_error(struct gotd_client *client, const struct got_error *err)
422 {
423 	struct imsgbuf ibuf;
424 
425 	log_warnx("uid %d: %s", client->euid, err->msg);
426 	if (err->code != GOT_ERR_EOF) {
427 		imsg_init(&ibuf, client->fd);
428 		gotd_imsg_send_error(&ibuf, 0, PROC_GOTD, err);
429 		imsg_clear(&ibuf);
430 	}
431 	disconnect(client);
432 }
433 
434 static const struct got_error *
435 send_repo_info(struct gotd_imsgev *iev, struct gotd_repo *repo)
436 {
437 	const struct got_error *err = NULL;
438 	struct gotd_imsg_info_repo irepo;
439 
440 	memset(&irepo, 0, sizeof(irepo));
441 
442 	if (strlcpy(irepo.repo_name, repo->name, sizeof(irepo.repo_name))
443 	    >= sizeof(irepo.repo_name))
444 		return got_error_msg(GOT_ERR_NO_SPACE, "repo name too long");
445 	if (strlcpy(irepo.repo_path, repo->path, sizeof(irepo.repo_path))
446 	    >= sizeof(irepo.repo_path))
447 		return got_error_msg(GOT_ERR_NO_SPACE, "repo path too long");
448 
449 	if (gotd_imsg_compose_event(iev, GOTD_IMSG_INFO_REPO, PROC_GOTD, -1,
450 	    &irepo, sizeof(irepo)) == -1) {
451 		err = got_error_from_errno("imsg compose INFO_REPO");
452 		if (err)
453 			return err;
454 	}
455 
456 	return NULL;
457 }
458 
459 static const struct got_error *
460 send_capability(struct gotd_client_capability *capa, struct gotd_imsgev* iev)
461 {
462 	const struct got_error *err = NULL;
463 	struct gotd_imsg_capability icapa;
464 	size_t len;
465 	struct ibuf *wbuf;
466 
467 	memset(&icapa, 0, sizeof(icapa));
468 
469 	icapa.key_len = strlen(capa->key);
470 	len = sizeof(icapa) + icapa.key_len;
471 	if (capa->value) {
472 		icapa.value_len = strlen(capa->value);
473 		len += icapa.value_len;
474 	}
475 
476 	wbuf = imsg_create(&iev->ibuf, GOTD_IMSG_CAPABILITY, 0, 0, len);
477 	if (wbuf == NULL) {
478 		err = got_error_from_errno("imsg_create CAPABILITY");
479 		return err;
480 	}
481 
482 	if (imsg_add(wbuf, &icapa, sizeof(icapa)) == -1)
483 		return got_error_from_errno("imsg_add CAPABILITY");
484 	if (imsg_add(wbuf, capa->key, icapa.key_len) == -1)
485 		return got_error_from_errno("imsg_add CAPABILITY");
486 	if (capa->value) {
487 		if (imsg_add(wbuf, capa->value, icapa.value_len) == -1)
488 			return got_error_from_errno("imsg_add CAPABILITY");
489 	}
490 
491 	wbuf->fd = -1;
492 	imsg_close(&iev->ibuf, wbuf);
493 
494 	gotd_imsg_event_add(iev);
495 
496 	return NULL;
497 }
498 
499 static const struct got_error *
500 send_client_info(struct gotd_imsgev *iev, struct gotd_client *client)
501 {
502 	const struct got_error *err = NULL;
503 	struct gotd_imsg_info_client iclient;
504 	struct gotd_child_proc *proc;
505 	size_t i;
506 
507 	memset(&iclient, 0, sizeof(iclient));
508 	iclient.euid = client->euid;
509 	iclient.egid = client->egid;
510 
511 	proc = get_client_proc(client);
512 	if (proc) {
513 		if (strlcpy(iclient.repo_name, proc->repo_path,
514 		    sizeof(iclient.repo_name)) >= sizeof(iclient.repo_name)) {
515 			return got_error_msg(GOT_ERR_NO_SPACE,
516 			    "repo name too long");
517 		}
518 		if (client_is_writing(client))
519 			iclient.is_writing = 1;
520 	}
521 
522 	iclient.state = client->state;
523 	iclient.ncapabilities = client->ncapabilities;
524 
525 	if (gotd_imsg_compose_event(iev, GOTD_IMSG_INFO_CLIENT, PROC_GOTD, -1,
526 	    &iclient, sizeof(iclient)) == -1) {
527 		err = got_error_from_errno("imsg compose INFO_CLIENT");
528 		if (err)
529 			return err;
530 	}
531 
532 	for (i = 0; i < client->ncapabilities; i++) {
533 		struct gotd_client_capability *capa;
534 		capa = &client->capabilities[i];
535 		err = send_capability(capa, iev);
536 		if (err)
537 			return err;
538 	}
539 
540 	return NULL;
541 }
542 
543 static const struct got_error *
544 send_info(struct gotd_client *client)
545 {
546 	const struct got_error *err = NULL;
547 	struct gotd_imsg_info info;
548 	uint64_t slot;
549 	struct gotd_repo *repo;
550 
551 	info.pid = gotd.pid;
552 	info.verbosity = gotd.verbosity;
553 	info.nrepos = gotd.nrepos;
554 	info.nclients = client_cnt - 1;
555 
556 	if (gotd_imsg_compose_event(&client->iev, GOTD_IMSG_INFO, PROC_GOTD, -1,
557 	    &info, sizeof(info)) == -1) {
558 		err = got_error_from_errno("imsg compose INFO");
559 		if (err)
560 			return err;
561 	}
562 
563 	TAILQ_FOREACH(repo, &gotd.repos, entry) {
564 		err = send_repo_info(&client->iev, repo);
565 		if (err)
566 			return err;
567 	}
568 
569 	for (slot = 0; slot < nitems(gotd_clients); slot++) {
570 		struct gotd_client *c;
571 		STAILQ_FOREACH(c, &gotd_clients[slot], entry) {
572 			if (c->id == client->id)
573 				continue;
574 			err = send_client_info(&client->iev, c);
575 			if (err)
576 				return err;
577 		}
578 	}
579 
580 	return NULL;
581 }
582 
583 static const struct got_error *
584 stop_gotd(struct gotd_client *client)
585 {
586 
587 	if (client->euid != 0)
588 		return got_error_set_errno(EPERM, "stop");
589 
590 	gotd_shutdown();
591 	/* NOTREACHED */
592 	return NULL;
593 }
594 
595 static struct gotd_repo *
596 find_repo_by_name(const char *repo_name)
597 {
598 	struct gotd_repo *repo;
599 	size_t namelen;
600 
601 	TAILQ_FOREACH(repo, &gotd.repos, entry) {
602 		namelen = strlen(repo->name);
603 		if (strncmp(repo->name, repo_name, namelen) != 0)
604 			continue;
605 		if (repo_name[namelen] == '\0' ||
606 		    strcmp(&repo_name[namelen], ".git") == 0)
607 			return repo;
608 	}
609 
610 	return NULL;
611 }
612 
613 static const struct got_error *
614 start_client_session(struct gotd_client *client, struct imsg *imsg)
615 {
616 	const struct got_error *err;
617 	struct gotd_imsg_list_refs ireq;
618 	struct gotd_repo *repo = NULL;
619 	size_t datalen;
620 
621 	log_debug("list-refs request from uid %d", client->euid);
622 
623 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
624 	if (datalen != sizeof(ireq))
625 		return got_error(GOT_ERR_PRIVSEP_LEN);
626 
627 	memcpy(&ireq, imsg->data, datalen);
628 
629 	if (ireq.client_is_reading) {
630 		err = ensure_client_is_not_writing(client);
631 		if (err)
632 			return err;
633 		repo = find_repo_by_name(ireq.repo_name);
634 		if (repo == NULL)
635 			return got_error(GOT_ERR_NOT_GIT_REPO);
636 		err = start_auth_child(client, GOTD_AUTH_READ, repo,
637 		    gotd.argv0, gotd.confpath, gotd.daemonize,
638 		    gotd.verbosity);
639 		if (err)
640 			return err;
641 	} else {
642 		err = ensure_client_is_not_reading(client);
643 		if (err)
644 			return err;
645 		repo = find_repo_by_name(ireq.repo_name);
646 		if (repo == NULL)
647 			return got_error(GOT_ERR_NOT_GIT_REPO);
648 		err = start_auth_child(client,
649 		    GOTD_AUTH_READ | GOTD_AUTH_WRITE,
650 		    repo, gotd.argv0, gotd.confpath, gotd.daemonize,
651 		    gotd.verbosity);
652 		if (err)
653 			return err;
654 	}
655 
656 	/* Flow continues upon authentication successs/failure or timeout. */
657 	return NULL;
658 }
659 
660 static const struct got_error *
661 forward_want(struct gotd_client *client, struct imsg *imsg)
662 {
663 	struct gotd_imsg_want ireq;
664 	struct gotd_imsg_want iwant;
665 	size_t datalen;
666 
667 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
668 	if (datalen != sizeof(ireq))
669 		return got_error(GOT_ERR_PRIVSEP_LEN);
670 
671 	memcpy(&ireq, imsg->data, datalen);
672 
673 	memset(&iwant, 0, sizeof(iwant));
674 	memcpy(iwant.object_id, ireq.object_id, SHA1_DIGEST_LENGTH);
675 	iwant.client_id = client->id;
676 
677 	if (gotd_imsg_compose_event(&client->repo_read->iev, GOTD_IMSG_WANT,
678 	    PROC_GOTD, -1, &iwant, sizeof(iwant)) == -1)
679 		return got_error_from_errno("imsg compose WANT");
680 
681 	return NULL;
682 }
683 
684 static const struct got_error *
685 forward_ref_update(struct gotd_client *client, struct imsg *imsg)
686 {
687 	const struct got_error *err = NULL;
688 	struct gotd_imsg_ref_update ireq;
689 	struct gotd_imsg_ref_update *iref = NULL;
690 	size_t datalen;
691 
692 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
693 	if (datalen < sizeof(ireq))
694 		return got_error(GOT_ERR_PRIVSEP_LEN);
695 	memcpy(&ireq, imsg->data, sizeof(ireq));
696 	if (datalen != sizeof(ireq) + ireq.name_len)
697 		return got_error(GOT_ERR_PRIVSEP_LEN);
698 
699 	iref = malloc(datalen);
700 	if (iref == NULL)
701 		return got_error_from_errno("malloc");
702 	memcpy(iref, imsg->data, datalen);
703 
704 	iref->client_id = client->id;
705 	if (gotd_imsg_compose_event(&client->repo_write->iev,
706 	    GOTD_IMSG_REF_UPDATE, PROC_GOTD, -1, iref, datalen) == -1)
707 		err = got_error_from_errno("imsg compose REF_UPDATE");
708 	free(iref);
709 	return err;
710 }
711 
712 static const struct got_error *
713 forward_have(struct gotd_client *client, struct imsg *imsg)
714 {
715 	struct gotd_imsg_have ireq;
716 	struct gotd_imsg_have ihave;
717 	size_t datalen;
718 
719 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
720 	if (datalen != sizeof(ireq))
721 		return got_error(GOT_ERR_PRIVSEP_LEN);
722 
723 	memcpy(&ireq, imsg->data, datalen);
724 
725 	memset(&ihave, 0, sizeof(ihave));
726 	memcpy(ihave.object_id, ireq.object_id, SHA1_DIGEST_LENGTH);
727 	ihave.client_id = client->id;
728 
729 	if (gotd_imsg_compose_event(&client->repo_read->iev, GOTD_IMSG_HAVE,
730 	    PROC_GOTD, -1, &ihave, sizeof(ihave)) == -1)
731 		return got_error_from_errno("imsg compose HAVE");
732 
733 	return NULL;
734 }
735 
736 static int
737 client_has_capability(struct gotd_client *client, const char *capastr)
738 {
739 	struct gotd_client_capability *capa;
740 	size_t i;
741 
742 	if (client->ncapabilities == 0)
743 		return 0;
744 
745 	for (i = 0; i < client->ncapabilities; i++) {
746 		capa = &client->capabilities[i];
747 		if (strcmp(capa->key, capastr) == 0)
748 			return 1;
749 	}
750 
751 	return 0;
752 }
753 
754 static const struct got_error *
755 recv_capabilities(struct gotd_client *client, struct imsg *imsg)
756 {
757 	struct gotd_imsg_capabilities icapas;
758 	size_t datalen;
759 
760 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
761 	if (datalen != sizeof(icapas))
762 		return got_error(GOT_ERR_PRIVSEP_LEN);
763 	memcpy(&icapas, imsg->data, sizeof(icapas));
764 
765 	client->ncapa_alloc = icapas.ncapabilities;
766 	client->capabilities = calloc(client->ncapa_alloc,
767 	    sizeof(*client->capabilities));
768 	if (client->capabilities == NULL) {
769 		client->ncapa_alloc = 0;
770 		return got_error_from_errno("calloc");
771 	}
772 
773 	log_debug("expecting %zu capabilities from uid %d",
774 	    client->ncapa_alloc, client->euid);
775 	return NULL;
776 }
777 
778 static const struct got_error *
779 recv_capability(struct gotd_client *client, struct imsg *imsg)
780 {
781 	struct gotd_imsg_capability icapa;
782 	struct gotd_client_capability *capa;
783 	size_t datalen;
784 	char *key, *value = NULL;
785 
786 	if (client->capabilities == NULL ||
787 	    client->ncapabilities >= client->ncapa_alloc) {
788 		return got_error_msg(GOT_ERR_BAD_REQUEST,
789 		    "unexpected capability received");
790 	}
791 
792 	memset(&icapa, 0, sizeof(icapa));
793 
794 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
795 	if (datalen < sizeof(icapa))
796 		return got_error(GOT_ERR_PRIVSEP_LEN);
797 	memcpy(&icapa, imsg->data, sizeof(icapa));
798 
799 	if (datalen != sizeof(icapa) + icapa.key_len + icapa.value_len)
800 		return got_error(GOT_ERR_PRIVSEP_LEN);
801 
802 	key = malloc(icapa.key_len + 1);
803 	if (key == NULL)
804 		return got_error_from_errno("malloc");
805 	if (icapa.value_len > 0) {
806 		value = malloc(icapa.value_len + 1);
807 		if (value == NULL) {
808 			free(key);
809 			return got_error_from_errno("malloc");
810 		}
811 	}
812 
813 	memcpy(key, imsg->data + sizeof(icapa), icapa.key_len);
814 	key[icapa.key_len] = '\0';
815 	if (value) {
816 		memcpy(value, imsg->data + sizeof(icapa) + icapa.key_len,
817 		    icapa.value_len);
818 		value[icapa.value_len] = '\0';
819 	}
820 
821 	capa = &client->capabilities[client->ncapabilities++];
822 	capa->key = key;
823 	capa->value = value;
824 
825 	if (value)
826 		log_debug("uid %d: capability %s=%s", client->euid, key, value);
827 	else
828 		log_debug("uid %d: capability %s", client->euid, key);
829 
830 	return NULL;
831 }
832 
833 static const struct got_error *
834 send_packfile(struct gotd_client *client)
835 {
836 	const struct got_error *err = NULL;
837 	struct gotd_imsg_send_packfile ipack;
838 	struct gotd_imsg_packfile_pipe ipipe;
839 	int pipe[2];
840 
841 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe) == -1)
842 		return got_error_from_errno("socketpair");
843 
844 	memset(&ipack, 0, sizeof(ipack));
845 	memset(&ipipe, 0, sizeof(ipipe));
846 
847 	ipack.client_id = client->id;
848 	if (client_has_capability(client, GOT_CAPA_SIDE_BAND_64K))
849 		ipack.report_progress = 1;
850 
851 	client->delta_cache_fd = got_opentempfd();
852 	if (client->delta_cache_fd == -1)
853 		return got_error_from_errno("got_opentempfd");
854 
855 	if (gotd_imsg_compose_event(&client->repo_read->iev,
856 	    GOTD_IMSG_SEND_PACKFILE, PROC_GOTD, client->delta_cache_fd,
857 	    &ipack, sizeof(ipack)) == -1) {
858 		err = got_error_from_errno("imsg compose SEND_PACKFILE");
859 		close(pipe[0]);
860 		close(pipe[1]);
861 		return err;
862 	}
863 
864 	ipipe.client_id = client->id;
865 
866 	/* Send pack pipe end 0 to repo_read. */
867 	if (gotd_imsg_compose_event(&client->repo_read->iev,
868 	    GOTD_IMSG_PACKFILE_PIPE, PROC_GOTD, pipe[0],
869 	        &ipipe, sizeof(ipipe)) == -1) {
870 		err = got_error_from_errno("imsg compose PACKFILE_PIPE");
871 		close(pipe[1]);
872 		return err;
873 	}
874 
875 	/* Send pack pipe end 1 to gotsh(1) (expects just an fd, no data). */
876 	if (gotd_imsg_compose_event(&client->iev,
877 	    GOTD_IMSG_PACKFILE_PIPE, PROC_GOTD, pipe[1], NULL, 0) == -1)
878 		err = got_error_from_errno("imsg compose PACKFILE_PIPE");
879 
880 	return err;
881 }
882 
883 static const struct got_error *
884 recv_packfile(struct gotd_client *client)
885 {
886 	const struct got_error *err = NULL;
887 	struct gotd_imsg_recv_packfile ipack;
888 	struct gotd_imsg_packfile_pipe ipipe;
889 	struct gotd_imsg_packidx_file ifile;
890 	char *basepath = NULL, *pack_path = NULL, *idx_path = NULL;
891 	int packfd = -1, idxfd = -1;
892 	int pipe[2] = { -1, -1 };
893 
894 	if (client->packfile_path) {
895 		return got_error_fmt(GOT_ERR_PRIVSEP_MSG,
896 		    "uid %d already has a pack file", client->euid);
897 	}
898 
899 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe) == -1)
900 		return got_error_from_errno("socketpair");
901 
902 	memset(&ipipe, 0, sizeof(ipipe));
903 	ipipe.client_id = client->id;
904 
905 	/* Send pack pipe end 0 to repo_write. */
906 	if (gotd_imsg_compose_event(&client->repo_write->iev,
907 	    GOTD_IMSG_PACKFILE_PIPE, PROC_GOTD, pipe[0],
908 	        &ipipe, sizeof(ipipe)) == -1) {
909 		err = got_error_from_errno("imsg compose PACKFILE_PIPE");
910 		pipe[0] = -1;
911 		goto done;
912 	}
913 	pipe[0] = -1;
914 
915 	/* Send pack pipe end 1 to gotsh(1) (expects just an fd, no data). */
916 	if (gotd_imsg_compose_event(&client->iev,
917 	    GOTD_IMSG_PACKFILE_PIPE, PROC_GOTD, pipe[1], NULL, 0) == -1)
918 		err = got_error_from_errno("imsg compose PACKFILE_PIPE");
919 	pipe[1] = -1;
920 
921 	if (asprintf(&basepath, "%s/%s/receiving-from-uid-%d.pack",
922 	    client->repo_write->repo_path, GOT_OBJECTS_PACK_DIR,
923 	    client->euid) == -1) {
924 		err = got_error_from_errno("asprintf");
925 		goto done;
926 	}
927 
928 	err = got_opentemp_named_fd(&pack_path, &packfd, basepath, "");
929 	if (err)
930 		goto done;
931 
932 	free(basepath);
933 	if (asprintf(&basepath, "%s/%s/receiving-from-uid-%d.idx",
934 	    client->repo_write->repo_path, GOT_OBJECTS_PACK_DIR,
935 	    client->euid) == -1) {
936 		err = got_error_from_errno("asprintf");
937 		basepath = NULL;
938 		goto done;
939 	}
940 	err = got_opentemp_named_fd(&idx_path, &idxfd, basepath, "");
941 	if (err)
942 		goto done;
943 
944 	memset(&ifile, 0, sizeof(ifile));
945 	ifile.client_id = client->id;
946 	if (gotd_imsg_compose_event(&client->repo_write->iev,
947 	    GOTD_IMSG_PACKIDX_FILE, PROC_GOTD, idxfd,
948 	    &ifile, sizeof(ifile)) == -1) {
949 		err = got_error_from_errno("imsg compose PACKIDX_FILE");
950 		idxfd = -1;
951 		goto done;
952 	}
953 	idxfd = -1;
954 
955 	memset(&ipack, 0, sizeof(ipack));
956 	ipack.client_id = client->id;
957 	if (client_has_capability(client, GOT_CAPA_REPORT_STATUS))
958 		ipack.report_status = 1;
959 
960 	if (gotd_imsg_compose_event(&client->repo_write->iev,
961 	    GOTD_IMSG_RECV_PACKFILE, PROC_GOTD, packfd,
962 	    &ipack, sizeof(ipack)) == -1) {
963 		err = got_error_from_errno("imsg compose RECV_PACKFILE");
964 		packfd = -1;
965 		goto done;
966 	}
967 	packfd = -1;
968 
969 done:
970 	free(basepath);
971 	if (pipe[0] != -1 && close(pipe[0]) == -1 && err == NULL)
972 		err = got_error_from_errno("close");
973 	if (pipe[1] != -1 && close(pipe[1]) == -1 && err == NULL)
974 		err = got_error_from_errno("close");
975 	if (packfd != -1 && close(packfd) == -1 && err == NULL)
976 		err = got_error_from_errno("close");
977 	if (idxfd != -1 && close(idxfd) == -1 && err == NULL)
978 		err = got_error_from_errno("close");
979 	if (err) {
980 		free(pack_path);
981 		free(idx_path);
982 	} else {
983 		client->packfile_path = pack_path;
984 		client->packidx_path = idx_path;
985 	}
986 	return err;
987 }
988 
989 static void
990 gotd_request(int fd, short events, void *arg)
991 {
992 	struct gotd_imsgev *iev = arg;
993 	struct imsgbuf *ibuf = &iev->ibuf;
994 	struct gotd_client *client = iev->handler_arg;
995 	const struct got_error *err = NULL;
996 	struct imsg imsg;
997 	ssize_t n;
998 
999 	if (events & EV_WRITE) {
1000 		while (ibuf->w.queued) {
1001 			n = msgbuf_write(&ibuf->w);
1002 			if (n == -1 && errno == EPIPE) {
1003 				/*
1004 				 * The client has closed its socket.
1005 				 * This can happen when Git clients are
1006 				 * done sending pack file data.
1007 				 */
1008 				msgbuf_clear(&ibuf->w);
1009 				continue;
1010 			} else if (n == -1 && errno != EAGAIN) {
1011 				err = got_error_from_errno("imsg_flush");
1012 				disconnect_on_error(client, err);
1013 				return;
1014 			}
1015 			if (n == 0) {
1016 				/* Connection closed. */
1017 				err = got_error(GOT_ERR_EOF);
1018 				disconnect_on_error(client, err);
1019 				return;
1020 			}
1021 		}
1022 
1023 		/* Disconnect gotctl(8) now that messages have been sent. */
1024 		if (!client_is_reading(client) && !client_is_writing(client)) {
1025 			disconnect(client);
1026 			return;
1027 		}
1028 	}
1029 
1030 	if ((events & EV_READ) == 0)
1031 		return;
1032 
1033 	memset(&imsg, 0, sizeof(imsg));
1034 
1035 	while (err == NULL) {
1036 		err = gotd_imsg_recv(&imsg, ibuf, 0);
1037 		if (err) {
1038 			if (err->code == GOT_ERR_PRIVSEP_READ)
1039 				err = NULL;
1040 			break;
1041 		}
1042 
1043 		evtimer_del(&client->tmo);
1044 
1045 		switch (imsg.hdr.type) {
1046 		case GOTD_IMSG_INFO:
1047 			err = send_info(client);
1048 			break;
1049 		case GOTD_IMSG_STOP:
1050 			err = stop_gotd(client);
1051 			break;
1052 		case GOTD_IMSG_LIST_REFS:
1053 			if (client->state != GOTD_STATE_EXPECT_LIST_REFS) {
1054 				err = got_error_msg(GOT_ERR_BAD_REQUEST,
1055 				    "unexpected list-refs request received");
1056 				break;
1057 			}
1058 			err = start_client_session(client, &imsg);
1059 			if (err)
1060 				break;
1061 			break;
1062 		case GOTD_IMSG_CAPABILITIES:
1063 			if (client->state != GOTD_STATE_EXPECT_CAPABILITIES) {
1064 				err = got_error_msg(GOT_ERR_BAD_REQUEST,
1065 				    "unexpected capabilities received");
1066 				break;
1067 			}
1068 			log_debug("receiving capabilities from uid %d",
1069 			    client->euid);
1070 			err = recv_capabilities(client, &imsg);
1071 			break;
1072 		case GOTD_IMSG_CAPABILITY:
1073 			if (client->state != GOTD_STATE_EXPECT_CAPABILITIES) {
1074 				err = got_error_msg(GOT_ERR_BAD_REQUEST,
1075 				    "unexpected capability received");
1076 				break;
1077 			}
1078 			err = recv_capability(client, &imsg);
1079 			if (err || client->ncapabilities < client->ncapa_alloc)
1080 				break;
1081 			if (client_is_reading(client)) {
1082 				client->state = GOTD_STATE_EXPECT_WANT;
1083 				log_debug("uid %d: expecting want-lines",
1084 				    client->euid);
1085 			} else if (client_is_writing(client)) {
1086 				client->state = GOTD_STATE_EXPECT_REF_UPDATE;
1087 				log_debug("uid %d: expecting ref-update-lines",
1088 				    client->euid);
1089 			} else
1090 				fatalx("client %d is both reading and writing",
1091 				    client->euid);
1092 			break;
1093 		case GOTD_IMSG_WANT:
1094 			if (client->state != GOTD_STATE_EXPECT_WANT) {
1095 				err = got_error_msg(GOT_ERR_BAD_REQUEST,
1096 				    "unexpected want-line received");
1097 				break;
1098 			}
1099 			log_debug("received want-line from uid %d",
1100 			    client->euid);
1101 			err = ensure_client_is_reading(client);
1102 			if (err)
1103 				break;
1104 			err = forward_want(client, &imsg);
1105 			break;
1106 		case GOTD_IMSG_REF_UPDATE:
1107 			if (client->state != GOTD_STATE_EXPECT_REF_UPDATE) {
1108 				err = got_error_msg(GOT_ERR_BAD_REQUEST,
1109 				    "unexpected ref-update-line received");
1110 				break;
1111 			}
1112 			log_debug("received ref-update-line from uid %d",
1113 			    client->euid);
1114 			err = ensure_client_is_writing(client);
1115 			if (err)
1116 				break;
1117 			err = forward_ref_update(client, &imsg);
1118 			if (err)
1119 				break;
1120 			client->state = GOTD_STATE_EXPECT_MORE_REF_UPDATES;
1121 			break;
1122 		case GOTD_IMSG_HAVE:
1123 			if (client->state != GOTD_STATE_EXPECT_HAVE) {
1124 				err = got_error_msg(GOT_ERR_BAD_REQUEST,
1125 				    "unexpected have-line received");
1126 				break;
1127 			}
1128 			log_debug("received have-line from uid %d",
1129 			    client->euid);
1130 			err = ensure_client_is_reading(client);
1131 			if (err)
1132 				break;
1133 			err = forward_have(client, &imsg);
1134 			if (err)
1135 				break;
1136 			break;
1137 		case GOTD_IMSG_FLUSH:
1138 			if (client->state == GOTD_STATE_EXPECT_WANT ||
1139 			    client->state == GOTD_STATE_EXPECT_HAVE) {
1140 				err = ensure_client_is_reading(client);
1141 				if (err)
1142 					break;
1143 			} else if (client->state ==
1144 			    GOTD_STATE_EXPECT_MORE_REF_UPDATES) {
1145 				err = ensure_client_is_writing(client);
1146 				if (err)
1147 					break;
1148 			} else {
1149 				err = got_error_msg(GOT_ERR_BAD_REQUEST,
1150 				    "unexpected flush-pkt received");
1151 				break;
1152 			}
1153 			log_debug("received flush-pkt from uid %d",
1154 			    client->euid);
1155 			if (client->state == GOTD_STATE_EXPECT_WANT) {
1156 				client->state = GOTD_STATE_EXPECT_HAVE;
1157 				log_debug("uid %d: expecting have-lines",
1158 				    client->euid);
1159 			} else if (client->state == GOTD_STATE_EXPECT_HAVE) {
1160 				client->state = GOTD_STATE_EXPECT_DONE;
1161 				log_debug("uid %d: expecting 'done'",
1162 				    client->euid);
1163 			} else if (client->state ==
1164 			    GOTD_STATE_EXPECT_MORE_REF_UPDATES) {
1165 				client->state = GOTD_STATE_EXPECT_PACKFILE;
1166 				log_debug("uid %d: expecting packfile",
1167 				    client->euid);
1168 				err = recv_packfile(client);
1169 			} else {
1170 				/* should not happen, see above */
1171 				err = got_error_msg(GOT_ERR_BAD_REQUEST,
1172 				    "unexpected client state");
1173 				break;
1174 			}
1175 			break;
1176 		case GOTD_IMSG_DONE:
1177 			if (client->state != GOTD_STATE_EXPECT_HAVE &&
1178 			    client->state != GOTD_STATE_EXPECT_DONE) {
1179 				err = got_error_msg(GOT_ERR_BAD_REQUEST,
1180 				    "unexpected flush-pkt received");
1181 				break;
1182 			}
1183 			log_debug("received 'done' from uid %d", client->euid);
1184 			err = ensure_client_is_reading(client);
1185 			if (err)
1186 				break;
1187 			client->state = GOTD_STATE_DONE;
1188 			err = send_packfile(client);
1189 			break;
1190 		default:
1191 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1192 			break;
1193 		}
1194 
1195 		imsg_free(&imsg);
1196 	}
1197 
1198 	if (err) {
1199 		if (err->code != GOT_ERR_EOF ||
1200 		    client->state != GOTD_STATE_EXPECT_PACKFILE)
1201 			disconnect_on_error(client, err);
1202 	} else {
1203 		gotd_imsg_event_add(&client->iev);
1204 		if (client->state == GOTD_STATE_EXPECT_LIST_REFS)
1205 			evtimer_add(&client->tmo, &auth_timeout);
1206 		else
1207 			evtimer_add(&client->tmo, &timeout);
1208 	}
1209 }
1210 
1211 static void
1212 gotd_request_timeout(int fd, short events, void *arg)
1213 {
1214 	struct gotd_client *client = arg;
1215 
1216 	log_debug("disconnecting uid %d due to timeout", client->euid);
1217 	disconnect(client);
1218 }
1219 
1220 static const struct got_error *
1221 recv_connect(uint32_t *client_id, struct imsg *imsg)
1222 {
1223 	const struct got_error *err = NULL;
1224 	struct gotd_imsg_connect iconnect;
1225 	size_t datalen;
1226 	int s = -1;
1227 	struct gotd_client *client = NULL;
1228 
1229 	*client_id = 0;
1230 
1231 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1232 	if (datalen != sizeof(iconnect))
1233 		return got_error(GOT_ERR_PRIVSEP_LEN);
1234 	memcpy(&iconnect, imsg->data, sizeof(iconnect));
1235 
1236 	s = imsg->fd;
1237 	if (s == -1) {
1238 		err = got_error(GOT_ERR_PRIVSEP_NO_FD);
1239 		goto done;
1240 	}
1241 
1242 	if (find_client(iconnect.client_id)) {
1243 		err = got_error_msg(GOT_ERR_CLIENT_ID, "duplicate client ID");
1244 		goto done;
1245 	}
1246 
1247 	client = calloc(1, sizeof(*client));
1248 	if (client == NULL) {
1249 		err = got_error_from_errno("calloc");
1250 		goto done;
1251 	}
1252 
1253 	*client_id = iconnect.client_id;
1254 
1255 	client->state = GOTD_STATE_EXPECT_LIST_REFS;
1256 	client->id = iconnect.client_id;
1257 	client->fd = s;
1258 	s = -1;
1259 	client->delta_cache_fd = -1;
1260 	/* The auth process will verify UID/GID for us. */
1261 	client->euid = iconnect.euid;
1262 	client->egid = iconnect.egid;
1263 	client->nref_updates = -1;
1264 
1265 	imsg_init(&client->iev.ibuf, client->fd);
1266 	client->iev.handler = gotd_request;
1267 	client->iev.events = EV_READ;
1268 	client->iev.handler_arg = client;
1269 
1270 	event_set(&client->iev.ev, client->fd, EV_READ, gotd_request,
1271 	    &client->iev);
1272 	gotd_imsg_event_add(&client->iev);
1273 
1274 	evtimer_set(&client->tmo, gotd_request_timeout, client);
1275 
1276 	add_client(client);
1277 	log_debug("%s: new client uid %d connected on fd %d", __func__,
1278 	    client->euid, client->fd);
1279 done:
1280 	if (err) {
1281 		struct gotd_child_proc *listen_proc = &gotd.listen_proc;
1282 		struct gotd_imsg_disconnect idisconnect;
1283 
1284 		idisconnect.client_id = client->id;
1285 		if (gotd_imsg_compose_event(&listen_proc->iev,
1286 		    GOTD_IMSG_DISCONNECT, PROC_GOTD, -1,
1287 		    &idisconnect, sizeof(idisconnect)) == -1)
1288 			log_warn("imsg compose DISCONNECT");
1289 
1290 		if (s != -1)
1291 			close(s);
1292 	}
1293 
1294 	return err;
1295 }
1296 
1297 static const char *gotd_proc_names[PROC_MAX] = {
1298 	"parent",
1299 	"listen",
1300 	"auth",
1301 	"repo_read",
1302 	"repo_write"
1303 };
1304 
1305 static void
1306 kill_proc(struct gotd_child_proc *proc, int fatal)
1307 {
1308 	if (fatal) {
1309 		log_warnx("sending SIGKILL to PID %d", proc->pid);
1310 		kill(proc->pid, SIGKILL);
1311 	} else
1312 		kill(proc->pid, SIGTERM);
1313 }
1314 
1315 static void
1316 gotd_shutdown(void)
1317 {
1318 	struct gotd_child_proc *proc;
1319 	uint64_t slot;
1320 
1321 	for (slot = 0; slot < nitems(gotd_clients); slot++) {
1322 		struct gotd_client *c, *tmp;
1323 
1324 		STAILQ_FOREACH_SAFE(c, &gotd_clients[slot], entry, tmp)
1325 			disconnect(c);
1326 	}
1327 
1328 	proc = &gotd.listen_proc;
1329 	msgbuf_clear(&proc->iev.ibuf.w);
1330 	close(proc->iev.ibuf.fd);
1331 	kill_proc(proc, 0);
1332 	wait_for_child(proc->pid);
1333 
1334 	log_info("terminating");
1335 	exit(0);
1336 }
1337 
1338 void
1339 gotd_sighdlr(int sig, short event, void *arg)
1340 {
1341 	/*
1342 	 * Normal signal handler rules don't apply because libevent
1343 	 * decouples for us.
1344 	 */
1345 
1346 	switch (sig) {
1347 	case SIGHUP:
1348 		log_info("%s: ignoring SIGHUP", __func__);
1349 		break;
1350 	case SIGUSR1:
1351 		log_info("%s: ignoring SIGUSR1", __func__);
1352 		break;
1353 	case SIGTERM:
1354 	case SIGINT:
1355 		gotd_shutdown();
1356 		log_warnx("gotd terminating");
1357 		exit(0);
1358 		break;
1359 	default:
1360 		fatalx("unexpected signal");
1361 	}
1362 }
1363 
1364 static const struct got_error *
1365 ensure_proc_is_reading(struct gotd_client *client,
1366     struct gotd_child_proc *proc)
1367 {
1368 	if (!client_is_reading(client)) {
1369 		kill_proc(proc, 1);
1370 		return got_error_fmt(GOT_ERR_BAD_PACKET,
1371 		    "PID %d handled a read-request for uid %d but this "
1372 		    "user is not reading from a repository", proc->pid,
1373 		    client->euid);
1374 	}
1375 
1376 	return NULL;
1377 }
1378 
1379 static const struct got_error *
1380 ensure_proc_is_writing(struct gotd_client *client,
1381     struct gotd_child_proc *proc)
1382 {
1383 	if (!client_is_writing(client)) {
1384 		kill_proc(proc, 1);
1385 		return got_error_fmt(GOT_ERR_BAD_PACKET,
1386 		    "PID %d handled a write-request for uid %d but this "
1387 		    "user is not writing to a repository", proc->pid,
1388 		    client->euid);
1389 	}
1390 
1391 	return NULL;
1392 }
1393 
1394 static int
1395 verify_imsg_src(struct gotd_client *client, struct gotd_child_proc *proc,
1396     struct imsg *imsg)
1397 {
1398 	const struct got_error *err;
1399 	struct gotd_child_proc *client_proc;
1400 	int ret = 0;
1401 
1402 	if (proc->type == PROC_REPO_READ || proc->type == PROC_REPO_WRITE) {
1403 		client_proc = get_client_proc(client);
1404 		if (client_proc == NULL)
1405 			fatalx("no process found for uid %d", client->euid);
1406 		if (proc->pid != client_proc->pid) {
1407 			kill_proc(proc, 1);
1408 			log_warnx("received message from PID %d for uid %d, "
1409 			    "while PID %d is the process serving this user",
1410 			    proc->pid, client->euid, client_proc->pid);
1411 			return 0;
1412 		}
1413 	}
1414 
1415 	switch (imsg->hdr.type) {
1416 	case GOTD_IMSG_ERROR:
1417 		ret = 1;
1418 		break;
1419 	case GOTD_IMSG_CONNECT:
1420 		if (proc->type != PROC_LISTEN) {
1421 			err = got_error_fmt(GOT_ERR_BAD_PACKET,
1422 			    "new connection for uid %d from PID %d "
1423 			    "which is not the listen process",
1424 			    proc->pid, client->euid);
1425 		} else
1426 			ret = 1;
1427 		break;
1428 	case GOTD_IMSG_ACCESS_GRANTED:
1429 		if (proc->type != PROC_AUTH) {
1430 			err = got_error_fmt(GOT_ERR_BAD_PACKET,
1431 			    "authentication of uid %d from PID %d "
1432 			    "which is not the auth process",
1433 			    proc->pid, client->euid);
1434 		} else
1435 			ret = 1;
1436 		break;
1437 	case GOTD_IMSG_REPO_CHILD_READY:
1438 		if (proc->type != PROC_REPO_READ &&
1439 		    proc->type != PROC_REPO_WRITE) {
1440 			err = got_error_fmt(GOT_ERR_BAD_PACKET,
1441 			    "unexpected \"ready\" signal from PID %d",
1442 			    proc->pid);
1443 		} else
1444 			ret = 1;
1445 		break;
1446 	case GOTD_IMSG_PACKFILE_DONE:
1447 		err = ensure_proc_is_reading(client, proc);
1448 		if (err)
1449 			log_warnx("uid %d: %s", client->euid, err->msg);
1450 		else
1451 			ret = 1;
1452 		break;
1453 	case GOTD_IMSG_PACKFILE_INSTALL:
1454 	case GOTD_IMSG_REF_UPDATES_START:
1455 	case GOTD_IMSG_REF_UPDATE:
1456 		err = ensure_proc_is_writing(client, proc);
1457 		if (err)
1458 			log_warnx("uid %d: %s", client->euid, err->msg);
1459 		else
1460 			ret = 1;
1461 		break;
1462 	default:
1463 		log_debug("%s: unexpected imsg %d", __func__, imsg->hdr.type);
1464 		break;
1465 	}
1466 
1467 	return ret;
1468 }
1469 
1470 static const struct got_error *
1471 list_refs_request(struct gotd_client *client, struct gotd_imsgev *iev)
1472 {
1473 	static const struct got_error *err;
1474 	struct gotd_imsg_list_refs_internal ilref;
1475 	int fd;
1476 
1477 	memset(&ilref, 0, sizeof(ilref));
1478 	ilref.client_id = client->id;
1479 
1480 	fd = dup(client->fd);
1481 	if (fd == -1)
1482 		return got_error_from_errno("dup");
1483 
1484 	if (gotd_imsg_compose_event(iev, GOTD_IMSG_LIST_REFS_INTERNAL,
1485 	    PROC_GOTD, fd, &ilref, sizeof(ilref)) == -1) {
1486 		err = got_error_from_errno("imsg compose WANT");
1487 		close(fd);
1488 		return err;
1489 	}
1490 
1491 	client->state = GOTD_STATE_EXPECT_CAPABILITIES;
1492 	log_debug("uid %d: expecting capabilities", client->euid);
1493 	return NULL;
1494 }
1495 
1496 static const struct got_error *
1497 recv_packfile_done(uint32_t *client_id, struct imsg *imsg)
1498 {
1499 	struct gotd_imsg_packfile_done idone;
1500 	size_t datalen;
1501 
1502 	log_debug("packfile-done received");
1503 
1504 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1505 	if (datalen != sizeof(idone))
1506 		return got_error(GOT_ERR_PRIVSEP_LEN);
1507 	memcpy(&idone, imsg->data, sizeof(idone));
1508 
1509 	*client_id = idone.client_id;
1510 	return NULL;
1511 }
1512 
1513 static const struct got_error *
1514 recv_packfile_install(uint32_t *client_id, struct imsg *imsg)
1515 {
1516 	struct gotd_imsg_packfile_install inst;
1517 	size_t datalen;
1518 
1519 	log_debug("packfile-install received");
1520 
1521 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1522 	if (datalen != sizeof(inst))
1523 		return got_error(GOT_ERR_PRIVSEP_LEN);
1524 	memcpy(&inst, imsg->data, sizeof(inst));
1525 
1526 	*client_id = inst.client_id;
1527 	return NULL;
1528 }
1529 
1530 static const struct got_error *
1531 recv_ref_updates_start(uint32_t *client_id, struct imsg *imsg)
1532 {
1533 	struct gotd_imsg_ref_updates_start istart;
1534 	size_t datalen;
1535 
1536 	log_debug("ref-updates-start received");
1537 
1538 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1539 	if (datalen != sizeof(istart))
1540 		return got_error(GOT_ERR_PRIVSEP_LEN);
1541 	memcpy(&istart, imsg->data, sizeof(istart));
1542 
1543 	*client_id = istart.client_id;
1544 	return NULL;
1545 }
1546 
1547 static const struct got_error *
1548 recv_ref_update(uint32_t *client_id, struct imsg *imsg)
1549 {
1550 	struct gotd_imsg_ref_update iref;
1551 	size_t datalen;
1552 
1553 	log_debug("ref-update received");
1554 
1555 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1556 	if (datalen < sizeof(iref))
1557 		return got_error(GOT_ERR_PRIVSEP_LEN);
1558 	memcpy(&iref, imsg->data, sizeof(iref));
1559 
1560 	*client_id = iref.client_id;
1561 	return NULL;
1562 }
1563 
1564 static const struct got_error *
1565 send_ref_update_ok(struct gotd_client *client,
1566     struct gotd_imsg_ref_update *iref, const char *refname)
1567 {
1568 	struct gotd_imsg_ref_update_ok iok;
1569 	struct ibuf *wbuf;
1570 	size_t len;
1571 
1572 	memset(&iok, 0, sizeof(iok));
1573 	iok.client_id = client->id;
1574 	memcpy(iok.old_id, iref->old_id, SHA1_DIGEST_LENGTH);
1575 	memcpy(iok.new_id, iref->new_id, SHA1_DIGEST_LENGTH);
1576 	iok.name_len = strlen(refname);
1577 
1578 	len = sizeof(iok) + iok.name_len;
1579 	wbuf = imsg_create(&client->iev.ibuf, GOTD_IMSG_REF_UPDATE_OK,
1580 	    PROC_GOTD, gotd.pid, len);
1581 	if (wbuf == NULL)
1582 		return got_error_from_errno("imsg_create REF_UPDATE_OK");
1583 
1584 	if (imsg_add(wbuf, &iok, sizeof(iok)) == -1)
1585 		return got_error_from_errno("imsg_add REF_UPDATE_OK");
1586 	if (imsg_add(wbuf, refname, iok.name_len) == -1)
1587 		return got_error_from_errno("imsg_add REF_UPDATE_OK");
1588 
1589 	wbuf->fd = -1;
1590 	imsg_close(&client->iev.ibuf, wbuf);
1591 	gotd_imsg_event_add(&client->iev);
1592 	return NULL;
1593 }
1594 
1595 static void
1596 send_refs_updated(struct gotd_client *client)
1597 {
1598 	if (gotd_imsg_compose_event(&client->iev,
1599 	    GOTD_IMSG_REFS_UPDATED, PROC_GOTD, -1, NULL, 0) == -1)
1600 		log_warn("imsg compose REFS_UPDATED");
1601 }
1602 
1603 static const struct got_error *
1604 send_ref_update_ng(struct gotd_client *client,
1605     struct gotd_imsg_ref_update *iref, const char *refname,
1606     const char *reason)
1607 {
1608 	const struct got_error *ng_err;
1609 	struct gotd_imsg_ref_update_ng ing;
1610 	struct ibuf *wbuf;
1611 	size_t len;
1612 
1613 	memset(&ing, 0, sizeof(ing));
1614 	ing.client_id = client->id;
1615 	memcpy(ing.old_id, iref->old_id, SHA1_DIGEST_LENGTH);
1616 	memcpy(ing.new_id, iref->new_id, SHA1_DIGEST_LENGTH);
1617 	ing.name_len = strlen(refname);
1618 
1619 	ng_err = got_error_fmt(GOT_ERR_REF_BUSY, "%s", reason);
1620 	ing.reason_len = strlen(ng_err->msg);
1621 
1622 	len = sizeof(ing) + ing.name_len + ing.reason_len;
1623 	wbuf = imsg_create(&client->iev.ibuf, GOTD_IMSG_REF_UPDATE_NG,
1624 	    PROC_GOTD, gotd.pid, len);
1625 	if (wbuf == NULL)
1626 		return got_error_from_errno("imsg_create REF_UPDATE_NG");
1627 
1628 	if (imsg_add(wbuf, &ing, sizeof(ing)) == -1)
1629 		return got_error_from_errno("imsg_add REF_UPDATE_NG");
1630 	if (imsg_add(wbuf, refname, ing.name_len) == -1)
1631 		return got_error_from_errno("imsg_add REF_UPDATE_NG");
1632 	if (imsg_add(wbuf, ng_err->msg, ing.reason_len) == -1)
1633 		return got_error_from_errno("imsg_add REF_UPDATE_NG");
1634 
1635 	wbuf->fd = -1;
1636 	imsg_close(&client->iev.ibuf, wbuf);
1637 	gotd_imsg_event_add(&client->iev);
1638 	return NULL;
1639 }
1640 
1641 static const struct got_error *
1642 install_pack(struct gotd_client *client, const char *repo_path,
1643     struct imsg *imsg)
1644 {
1645 	const struct got_error *err = NULL;
1646 	struct gotd_imsg_packfile_install inst;
1647 	char hex[SHA1_DIGEST_STRING_LENGTH];
1648 	size_t datalen;
1649 	char *packfile_path = NULL, *packidx_path = NULL;
1650 
1651 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1652 	if (datalen != sizeof(inst))
1653 		return got_error(GOT_ERR_PRIVSEP_LEN);
1654 	memcpy(&inst, imsg->data, sizeof(inst));
1655 
1656 	if (client->packfile_path == NULL)
1657 		return got_error_msg(GOT_ERR_BAD_REQUEST,
1658 		    "client has no pack file");
1659 	if (client->packidx_path == NULL)
1660 		return got_error_msg(GOT_ERR_BAD_REQUEST,
1661 		    "client has no pack file index");
1662 
1663 	if (got_sha1_digest_to_str(inst.pack_sha1, hex, sizeof(hex)) == NULL)
1664 		return got_error_msg(GOT_ERR_NO_SPACE,
1665 		    "could not convert pack file SHA1 to hex");
1666 
1667 	if (asprintf(&packfile_path, "/%s/%s/pack-%s.pack",
1668 	    repo_path, GOT_OBJECTS_PACK_DIR, hex) == -1) {
1669 		err = got_error_from_errno("asprintf");
1670 		goto done;
1671 	}
1672 
1673 	if (asprintf(&packidx_path, "/%s/%s/pack-%s.idx",
1674 	    repo_path, GOT_OBJECTS_PACK_DIR, hex) == -1) {
1675 		err = got_error_from_errno("asprintf");
1676 		goto done;
1677 	}
1678 
1679 	if (rename(client->packfile_path, packfile_path) == -1) {
1680 		err = got_error_from_errno3("rename", client->packfile_path,
1681 		    packfile_path);
1682 		goto done;
1683 	}
1684 
1685 	free(client->packfile_path);
1686 	client->packfile_path = NULL;
1687 
1688 	if (rename(client->packidx_path, packidx_path) == -1) {
1689 		err = got_error_from_errno3("rename", client->packidx_path,
1690 		    packidx_path);
1691 		goto done;
1692 	}
1693 
1694 	free(client->packidx_path);
1695 	client->packidx_path = NULL;
1696 done:
1697 	free(packfile_path);
1698 	free(packidx_path);
1699 	return err;
1700 }
1701 
1702 static const struct got_error *
1703 begin_ref_updates(struct gotd_client *client, struct imsg *imsg)
1704 {
1705 	struct gotd_imsg_ref_updates_start istart;
1706 	size_t datalen;
1707 
1708 	if (client->nref_updates != -1)
1709 		return got_error(GOT_ERR_PRIVSEP_MSG);
1710 
1711 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1712 	if (datalen != sizeof(istart))
1713 		return got_error(GOT_ERR_PRIVSEP_LEN);
1714 	memcpy(&istart, imsg->data, sizeof(istart));
1715 
1716 	if (istart.nref_updates <= 0)
1717 		return got_error(GOT_ERR_PRIVSEP_MSG);
1718 
1719 	client->nref_updates = istart.nref_updates;
1720 	return NULL;
1721 }
1722 
1723 static const struct got_error *
1724 update_ref(struct gotd_client *client, const char *repo_path,
1725     struct imsg *imsg)
1726 {
1727 	const struct got_error *err = NULL;
1728 	struct got_repository *repo = NULL;
1729 	struct got_reference *ref = NULL;
1730 	struct gotd_imsg_ref_update iref;
1731 	struct got_object_id old_id, new_id;
1732 	struct got_object_id *id = NULL;
1733 	struct got_object *obj = NULL;
1734 	char *refname = NULL;
1735 	size_t datalen;
1736 	int locked = 0;
1737 
1738 	log_debug("update-ref from uid %d", client->euid);
1739 
1740 	if (client->nref_updates <= 0)
1741 		return got_error(GOT_ERR_PRIVSEP_MSG);
1742 
1743 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1744 	if (datalen < sizeof(iref))
1745 		return got_error(GOT_ERR_PRIVSEP_LEN);
1746 	memcpy(&iref, imsg->data, sizeof(iref));
1747 	if (datalen != sizeof(iref) + iref.name_len)
1748 		return got_error(GOT_ERR_PRIVSEP_LEN);
1749 	refname = malloc(iref.name_len + 1);
1750 	if (refname == NULL)
1751 		return got_error_from_errno("malloc");
1752 	memcpy(refname, imsg->data + sizeof(iref), iref.name_len);
1753 	refname[iref.name_len] = '\0';
1754 
1755 	log_debug("updating ref %s for uid %d", refname, client->euid);
1756 
1757 	err = got_repo_open(&repo, repo_path, NULL, NULL);
1758 	if (err)
1759 		goto done;
1760 
1761 	memcpy(old_id.sha1, iref.old_id, SHA1_DIGEST_LENGTH);
1762 	memcpy(new_id.sha1, iref.new_id, SHA1_DIGEST_LENGTH);
1763 	err = got_object_open(&obj, repo, &new_id);
1764 	if (err)
1765 		goto done;
1766 
1767 	if (iref.ref_is_new) {
1768 		err = got_ref_open(&ref, repo, refname, 0);
1769 		if (err) {
1770 			if (err->code != GOT_ERR_NOT_REF)
1771 				goto done;
1772 			err = got_ref_alloc(&ref, refname, &new_id);
1773 			if (err)
1774 				goto done;
1775 			err = got_ref_write(ref, repo); /* will lock/unlock */
1776 			if (err)
1777 				goto done;
1778 		} else {
1779 			err = got_error_fmt(GOT_ERR_REF_BUSY,
1780 			    "%s has been created by someone else "
1781 			    "while transaction was in progress",
1782 			    got_ref_get_name(ref));
1783 			goto done;
1784 		}
1785 	} else {
1786 		err = got_ref_open(&ref, repo, refname, 1 /* lock */);
1787 		if (err)
1788 			goto done;
1789 		locked = 1;
1790 
1791 		err = got_ref_resolve(&id, repo, ref);
1792 		if (err)
1793 			goto done;
1794 
1795 		if (got_object_id_cmp(id, &old_id) != 0) {
1796 			err = got_error_fmt(GOT_ERR_REF_BUSY,
1797 			    "%s has been modified by someone else "
1798 			    "while transaction was in progress",
1799 			    got_ref_get_name(ref));
1800 			goto done;
1801 		}
1802 
1803 		err = got_ref_change_ref(ref, &new_id);
1804 		if (err)
1805 			goto done;
1806 
1807 		err = got_ref_write(ref, repo);
1808 		if (err)
1809 			goto done;
1810 
1811 		free(id);
1812 		id = NULL;
1813 	}
1814 done:
1815 	if (err) {
1816 		if (err->code == GOT_ERR_LOCKFILE_TIMEOUT) {
1817 			err = got_error_fmt(GOT_ERR_LOCKFILE_TIMEOUT,
1818 			    "could not acquire exclusive file lock for %s",
1819 			    refname);
1820 		}
1821 		send_ref_update_ng(client, &iref, refname, err->msg);
1822 	} else
1823 		send_ref_update_ok(client, &iref, refname);
1824 
1825 	if (client->nref_updates > 0) {
1826 		client->nref_updates--;
1827 		if (client->nref_updates == 0)
1828 			send_refs_updated(client);
1829 
1830 	}
1831 	if (locked) {
1832 		const struct got_error *unlock_err;
1833 		unlock_err = got_ref_unlock(ref);
1834 		if (unlock_err && err == NULL)
1835 			err = unlock_err;
1836 	}
1837 	if (ref)
1838 		got_ref_close(ref);
1839 	if (obj)
1840 		got_object_close(obj);
1841 	if (repo)
1842 		got_repo_close(repo);
1843 	free(refname);
1844 	free(id);
1845 	return err;
1846 }
1847 
1848 static void
1849 gotd_dispatch_listener(int fd, short event, void *arg)
1850 {
1851 	struct gotd_imsgev *iev = arg;
1852 	struct imsgbuf *ibuf = &iev->ibuf;
1853 	struct gotd_child_proc *proc = &gotd.listen_proc;
1854 	ssize_t n;
1855 	int shut = 0;
1856 	struct imsg imsg;
1857 
1858 	if (proc->iev.ibuf.fd != fd)
1859 		fatalx("%s: unexpected fd %d", __func__, fd);
1860 
1861 	if (event & EV_READ) {
1862 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
1863 			fatal("imsg_read error");
1864 		if (n == 0) {
1865 			/* Connection closed. */
1866 			shut = 1;
1867 			goto done;
1868 		}
1869 	}
1870 
1871 	if (event & EV_WRITE) {
1872 		n = msgbuf_write(&ibuf->w);
1873 		if (n == -1 && errno != EAGAIN)
1874 			fatal("msgbuf_write");
1875 		if (n == 0) {
1876 			/* Connection closed. */
1877 			shut = 1;
1878 			goto done;
1879 		}
1880 	}
1881 
1882 	for (;;) {
1883 		const struct got_error *err = NULL;
1884 		struct gotd_client *client = NULL;
1885 		uint32_t client_id = 0;
1886 		int do_disconnect = 0;
1887 
1888 		if ((n = imsg_get(ibuf, &imsg)) == -1)
1889 			fatal("%s: imsg_get error", __func__);
1890 		if (n == 0)	/* No more messages. */
1891 			break;
1892 
1893 		switch (imsg.hdr.type) {
1894 		case GOTD_IMSG_ERROR:
1895 			do_disconnect = 1;
1896 			err = gotd_imsg_recv_error(&client_id, &imsg);
1897 			break;
1898 		case GOTD_IMSG_CONNECT:
1899 			err = recv_connect(&client_id, &imsg);
1900 			break;
1901 		default:
1902 			log_debug("unexpected imsg %d", imsg.hdr.type);
1903 			break;
1904 		}
1905 
1906 		client = find_client(client_id);
1907 		if (client == NULL) {
1908 			log_warnx("%s: client not found", __func__);
1909 			imsg_free(&imsg);
1910 			continue;
1911 		}
1912 
1913 		if (err)
1914 			log_warnx("uid %d: %s", client->euid, err->msg);
1915 
1916 		if (do_disconnect) {
1917 			if (err)
1918 				disconnect_on_error(client, err);
1919 			else
1920 				disconnect(client);
1921 		}
1922 
1923 		imsg_free(&imsg);
1924 	}
1925 done:
1926 	if (!shut) {
1927 		gotd_imsg_event_add(iev);
1928 	} else {
1929 		/* This pipe is dead. Remove its event handler */
1930 		event_del(&iev->ev);
1931 		event_loopexit(NULL);
1932 	}
1933 }
1934 
1935 static void
1936 gotd_dispatch_auth_child(int fd, short event, void *arg)
1937 {
1938 	const struct got_error *err = NULL;
1939 	struct gotd_imsgev *iev = arg;
1940 	struct imsgbuf *ibuf = &iev->ibuf;
1941 	struct gotd_client *client;
1942 	struct gotd_repo *repo = NULL;
1943 	ssize_t n;
1944 	int shut = 0;
1945 	struct imsg imsg;
1946 	uint32_t client_id = 0;
1947 	int do_disconnect = 0;
1948 	enum gotd_procid proc_type;
1949 
1950 	client = find_client_by_proc_fd(fd);
1951 	if (client == NULL)
1952 		fatalx("cannot find client for fd %d", fd);
1953 
1954 	if (client->auth == NULL)
1955 		fatalx("cannot find auth child process for fd %d", fd);
1956 
1957 	if (event & EV_READ) {
1958 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
1959 			fatal("imsg_read error");
1960 		if (n == 0) {
1961 			/* Connection closed. */
1962 			shut = 1;
1963 			goto done;
1964 		}
1965 	}
1966 
1967 	if (event & EV_WRITE) {
1968 		n = msgbuf_write(&ibuf->w);
1969 		if (n == -1 && errno != EAGAIN)
1970 			fatal("msgbuf_write");
1971 		if (n == 0) {
1972 			/* Connection closed. */
1973 			shut = 1;
1974 		}
1975 		goto done;
1976 	}
1977 
1978 	if (client->auth->iev.ibuf.fd != fd)
1979 		fatalx("%s: unexpected fd %d", __func__, fd);
1980 
1981 	if ((n = imsg_get(ibuf, &imsg)) == -1)
1982 		fatal("%s: imsg_get error", __func__);
1983 	if (n == 0)	/* No more messages. */
1984 		return;
1985 
1986 	evtimer_del(&client->tmo);
1987 
1988 	switch (imsg.hdr.type) {
1989 	case GOTD_IMSG_ERROR:
1990 		do_disconnect = 1;
1991 		err = gotd_imsg_recv_error(&client_id, &imsg);
1992 		break;
1993 	case GOTD_IMSG_ACCESS_GRANTED:
1994 		break;
1995 	default:
1996 		do_disconnect = 1;
1997 		log_debug("unexpected imsg %d", imsg.hdr.type);
1998 		break;
1999 	}
2000 
2001 	if (!verify_imsg_src(client, client->auth, &imsg)) {
2002 		do_disconnect = 1;
2003 		log_debug("dropping imsg type %d from PID %d",
2004 		    imsg.hdr.type, client->auth->pid);
2005 	}
2006 	imsg_free(&imsg);
2007 
2008 	if (do_disconnect) {
2009 		if (err)
2010 			disconnect_on_error(client, err);
2011 		else
2012 			disconnect(client);
2013 		goto done;
2014 	}
2015 
2016 	repo = find_repo_by_name(client->auth->repo_name);
2017 	if (repo == NULL) {
2018 		err = got_error(GOT_ERR_NOT_GIT_REPO);
2019 		goto done;
2020 	}
2021 	kill_auth_proc(client);
2022 
2023 	log_info("authenticated uid %d for repository %s\n",
2024 	    client->euid, repo->name);
2025 
2026 	if (client->required_auth & GOTD_AUTH_WRITE)
2027 		proc_type = PROC_REPO_WRITE;
2028 	else
2029 		proc_type = PROC_REPO_READ;
2030 
2031 	err = start_repo_child(client, proc_type, repo, gotd.argv0,
2032 	    gotd.confpath, gotd.daemonize, gotd.verbosity);
2033 done:
2034 	if (err)
2035 		log_warnx("uid %d: %s", client->euid, err->msg);
2036 
2037 	/* We might have killed the auth process by now. */
2038 	if (client->auth != NULL) {
2039 		if (!shut) {
2040 			gotd_imsg_event_add(iev);
2041 		} else {
2042 			/* This pipe is dead. Remove its event handler */
2043 			event_del(&iev->ev);
2044 		}
2045 	}
2046 }
2047 
2048 static void
2049 gotd_dispatch_repo_child(int fd, short event, void *arg)
2050 {
2051 	struct gotd_imsgev *iev = arg;
2052 	struct imsgbuf *ibuf = &iev->ibuf;
2053 	struct gotd_child_proc *proc = NULL;
2054 	struct gotd_client *client = NULL;
2055 	ssize_t n;
2056 	int shut = 0;
2057 	struct imsg imsg;
2058 
2059 	if (event & EV_READ) {
2060 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
2061 			fatal("imsg_read error");
2062 		if (n == 0) {
2063 			/* Connection closed. */
2064 			shut = 1;
2065 			goto done;
2066 		}
2067 	}
2068 
2069 	if (event & EV_WRITE) {
2070 		n = msgbuf_write(&ibuf->w);
2071 		if (n == -1 && errno != EAGAIN)
2072 			fatal("msgbuf_write");
2073 		if (n == 0) {
2074 			/* Connection closed. */
2075 			shut = 1;
2076 			goto done;
2077 		}
2078 	}
2079 
2080 	client = find_client_by_proc_fd(fd);
2081 	if (client == NULL)
2082 		fatalx("cannot find client for fd %d", fd);
2083 
2084 	proc = get_client_proc(client);
2085 	if (proc == NULL)
2086 		fatalx("cannot find child process for fd %d", fd);
2087 
2088 	for (;;) {
2089 		const struct got_error *err = NULL;
2090 		uint32_t client_id = 0;
2091 		int do_disconnect = 0;
2092 		int do_list_refs = 0, do_ref_updates = 0, do_ref_update = 0;
2093 		int do_packfile_install = 0;
2094 
2095 		if ((n = imsg_get(ibuf, &imsg)) == -1)
2096 			fatal("%s: imsg_get error", __func__);
2097 		if (n == 0)	/* No more messages. */
2098 			break;
2099 
2100 		switch (imsg.hdr.type) {
2101 		case GOTD_IMSG_ERROR:
2102 			do_disconnect = 1;
2103 			err = gotd_imsg_recv_error(&client_id, &imsg);
2104 			break;
2105 		case GOTD_IMSG_REPO_CHILD_READY:
2106 			do_list_refs = 1;
2107 			break;
2108 		case GOTD_IMSG_PACKFILE_DONE:
2109 			do_disconnect = 1;
2110 			err = recv_packfile_done(&client_id, &imsg);
2111 			break;
2112 		case GOTD_IMSG_PACKFILE_INSTALL:
2113 			err = recv_packfile_install(&client_id, &imsg);
2114 			if (err == NULL)
2115 				do_packfile_install = 1;
2116 			break;
2117 		case GOTD_IMSG_REF_UPDATES_START:
2118 			err = recv_ref_updates_start(&client_id, &imsg);
2119 			if (err == NULL)
2120 				do_ref_updates = 1;
2121 			break;
2122 		case GOTD_IMSG_REF_UPDATE:
2123 			err = recv_ref_update(&client_id, &imsg);
2124 			if (err == NULL)
2125 				do_ref_update = 1;
2126 			break;
2127 		default:
2128 			log_debug("unexpected imsg %d", imsg.hdr.type);
2129 			break;
2130 		}
2131 
2132 		if (!verify_imsg_src(client, proc, &imsg)) {
2133 			log_debug("dropping imsg type %d from PID %d",
2134 			    imsg.hdr.type, proc->pid);
2135 			imsg_free(&imsg);
2136 			continue;
2137 		}
2138 		if (err)
2139 			log_warnx("uid %d: %s", client->euid, err->msg);
2140 
2141 		if (do_disconnect) {
2142 			if (err)
2143 				disconnect_on_error(client, err);
2144 			else
2145 				disconnect(client);
2146 		} else {
2147 			if (do_list_refs)
2148 				err = list_refs_request(client, iev);
2149 			else if (do_packfile_install)
2150 				err = install_pack(client, proc->repo_path,
2151 				    &imsg);
2152 			else if (do_ref_updates)
2153 				err = begin_ref_updates(client, &imsg);
2154 			else if (do_ref_update)
2155 				err = update_ref(client, proc->repo_path,
2156 				    &imsg);
2157 			if (err)
2158 				log_warnx("uid %d: %s", client->euid, err->msg);
2159 		}
2160 		imsg_free(&imsg);
2161 	}
2162 done:
2163 	if (!shut) {
2164 		gotd_imsg_event_add(iev);
2165 	} else {
2166 		/* This pipe is dead. Remove its event handler */
2167 		event_del(&iev->ev);
2168 		event_loopexit(NULL);
2169 	}
2170 }
2171 
2172 static pid_t
2173 start_child(enum gotd_procid proc_id, const char *repo_path,
2174     char *argv0, const char *confpath, int fd, int daemonize, int verbosity)
2175 {
2176 	char	*argv[11];
2177 	int	 argc = 0;
2178 	pid_t	 pid;
2179 
2180 	switch (pid = fork()) {
2181 	case -1:
2182 		fatal("cannot fork");
2183 	case 0:
2184 		break;
2185 	default:
2186 		close(fd);
2187 		return pid;
2188 	}
2189 
2190 	if (fd != GOTD_FILENO_MSG_PIPE) {
2191 		if (dup2(fd, GOTD_FILENO_MSG_PIPE) == -1)
2192 			fatal("cannot setup imsg fd");
2193 	} else if (fcntl(fd, F_SETFD, 0) == -1)
2194 		fatal("cannot setup imsg fd");
2195 
2196 	argv[argc++] = argv0;
2197 	switch (proc_id) {
2198 	case PROC_LISTEN:
2199 		argv[argc++] = (char *)"-L";
2200 		break;
2201 	case PROC_AUTH:
2202 		argv[argc++] = (char *)"-A";
2203 		break;
2204 	case PROC_REPO_READ:
2205 		argv[argc++] = (char *)"-R";
2206 		break;
2207 	case PROC_REPO_WRITE:
2208 		argv[argc++] = (char *)"-W";
2209 		break;
2210 	default:
2211 		fatalx("invalid process id %d", proc_id);
2212 	}
2213 
2214 	argv[argc++] = (char *)"-f";
2215 	argv[argc++] = (char *)confpath;
2216 
2217 	if (repo_path) {
2218 		argv[argc++] = (char *)"-P";
2219 		argv[argc++] = (char *)repo_path;
2220 	}
2221 
2222 	if (!daemonize)
2223 		argv[argc++] = (char *)"-d";
2224 	if (verbosity > 0)
2225 		argv[argc++] = (char *)"-v";
2226 	if (verbosity > 1)
2227 		argv[argc++] = (char *)"-v";
2228 	argv[argc++] = NULL;
2229 
2230 	execvp(argv0, argv);
2231 	fatal("execvp");
2232 }
2233 
2234 static void
2235 start_listener(char *argv0, const char *confpath, int daemonize, int verbosity)
2236 {
2237 	struct gotd_child_proc *proc = &gotd.listen_proc;
2238 
2239 	proc->type = PROC_LISTEN;
2240 
2241 	if (socketpair(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK,
2242 	    PF_UNSPEC, proc->pipe) == -1)
2243 		fatal("socketpair");
2244 
2245 	proc->pid = start_child(proc->type, NULL, argv0, confpath,
2246 	    proc->pipe[1], daemonize, verbosity);
2247 	imsg_init(&proc->iev.ibuf, proc->pipe[0]);
2248 	proc->iev.handler = gotd_dispatch_listener;
2249 	proc->iev.events = EV_READ;
2250 	proc->iev.handler_arg = NULL;
2251 }
2252 
2253 static const struct got_error *
2254 start_repo_child(struct gotd_client *client, enum gotd_procid proc_type,
2255     struct gotd_repo *repo, char *argv0, const char *confpath,
2256     int daemonize, int verbosity)
2257 {
2258 	struct gotd_child_proc *proc;
2259 
2260 	if (proc_type != PROC_REPO_READ && proc_type != PROC_REPO_WRITE)
2261 		return got_error_msg(GOT_ERR_NOT_IMPL, "bad process type");
2262 
2263 	proc = calloc(1, sizeof(*proc));
2264 	if (proc == NULL)
2265 		return got_error_from_errno("calloc");
2266 
2267 	proc->type = proc_type;
2268 	if (strlcpy(proc->repo_name, repo->name,
2269 	    sizeof(proc->repo_name)) >= sizeof(proc->repo_name))
2270 		fatalx("repository name too long: %s", repo->name);
2271 	log_debug("starting %s for repository %s",
2272 	    proc->type == PROC_REPO_READ ? "reader" : "writer", repo->name);
2273 	if (realpath(repo->path, proc->repo_path) == NULL)
2274 		fatal("%s", repo->path);
2275 	if (socketpair(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK,
2276 	    PF_UNSPEC, proc->pipe) == -1)
2277 		fatal("socketpair");
2278 	proc->pid = start_child(proc->type, proc->repo_path, argv0,
2279 	    confpath, proc->pipe[1], daemonize, verbosity);
2280 	imsg_init(&proc->iev.ibuf, proc->pipe[0]);
2281 	log_debug("proc %s %s is on fd %d",
2282 	    gotd_proc_names[proc->type], proc->repo_path,
2283 	    proc->pipe[0]);
2284 	proc->iev.handler = gotd_dispatch_repo_child;
2285 	proc->iev.events = EV_READ;
2286 	proc->iev.handler_arg = NULL;
2287 	event_set(&proc->iev.ev, proc->iev.ibuf.fd, EV_READ,
2288 	    gotd_dispatch_repo_child, &proc->iev);
2289 	gotd_imsg_event_add(&proc->iev);
2290 
2291 	if (proc->type == PROC_REPO_READ)
2292 		client->repo_read = proc;
2293 	else
2294 		client->repo_write = proc;
2295 
2296 	return NULL;
2297 }
2298 
2299 static const struct got_error *
2300 start_auth_child(struct gotd_client *client, int required_auth,
2301     struct gotd_repo *repo, char *argv0, const char *confpath,
2302     int daemonize, int verbosity)
2303 {
2304 	const struct got_error *err = NULL;
2305 	struct gotd_child_proc *proc;
2306 	struct gotd_imsg_auth iauth;
2307 	int fd;
2308 
2309 	memset(&iauth, 0, sizeof(iauth));
2310 
2311 	fd = dup(client->fd);
2312 	if (fd == -1)
2313 		return got_error_from_errno("dup");
2314 
2315 	proc = calloc(1, sizeof(*proc));
2316 	if (proc == NULL) {
2317 		err = got_error_from_errno("calloc");
2318 		close(fd);
2319 		return err;
2320 	}
2321 
2322 	proc->type = PROC_AUTH;
2323 	if (strlcpy(proc->repo_name, repo->name,
2324 	    sizeof(proc->repo_name)) >= sizeof(proc->repo_name))
2325 		fatalx("repository name too long: %s", repo->name);
2326 	log_debug("starting auth for uid %d repository %s",
2327 	    client->euid, repo->name);
2328 	if (realpath(repo->path, proc->repo_path) == NULL)
2329 		fatal("%s", repo->path);
2330 	if (socketpair(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK,
2331 	    PF_UNSPEC, proc->pipe) == -1)
2332 		fatal("socketpair");
2333 	proc->pid = start_child(proc->type, proc->repo_path, argv0,
2334 	    confpath, proc->pipe[1], daemonize, verbosity);
2335 	imsg_init(&proc->iev.ibuf, proc->pipe[0]);
2336 	log_debug("proc %s %s is on fd %d",
2337 	    gotd_proc_names[proc->type], proc->repo_path,
2338 	    proc->pipe[0]);
2339 	proc->iev.handler = gotd_dispatch_auth_child;
2340 	proc->iev.events = EV_READ;
2341 	proc->iev.handler_arg = NULL;
2342 	event_set(&proc->iev.ev, proc->iev.ibuf.fd, EV_READ,
2343 	    gotd_dispatch_auth_child, &proc->iev);
2344 	gotd_imsg_event_add(&proc->iev);
2345 
2346 	iauth.euid = client->euid;
2347 	iauth.egid = client->egid;
2348 	iauth.required_auth = required_auth;
2349 	iauth.client_id = client->id;
2350 	if (gotd_imsg_compose_event(&proc->iev, GOTD_IMSG_AUTHENTICATE,
2351 	    PROC_GOTD, fd, &iauth, sizeof(iauth)) == -1) {
2352 		log_warn("imsg compose AUTHENTICATE");
2353 		close(fd);
2354 		/* Let the auth_timeout handler tidy up. */
2355 	}
2356 
2357 	client->auth = proc;
2358 	client->required_auth = required_auth;
2359 	return NULL;
2360 }
2361 
2362 static void
2363 apply_unveil_repo_readonly(const char *repo_path)
2364 {
2365 	if (unveil(repo_path, "r") == -1)
2366 		fatal("unveil %s", repo_path);
2367 
2368 	if (unveil(NULL, NULL) == -1)
2369 		fatal("unveil");
2370 }
2371 
2372 static void
2373 apply_unveil_none(void)
2374 {
2375 	if (unveil("/", "") == -1)
2376 		fatal("unveil");
2377 
2378 	if (unveil(NULL, NULL) == -1)
2379 		fatal("unveil");
2380 }
2381 
2382 static void
2383 apply_unveil(void)
2384 {
2385 	struct gotd_repo *repo;
2386 
2387 	if (unveil(gotd.argv0, "x") == -1)
2388 		fatal("unveil %s", gotd.argv0);
2389 
2390 	TAILQ_FOREACH(repo, &gotd.repos, entry) {
2391 		if (unveil(repo->path, "rwc") == -1)
2392 			fatal("unveil %s", repo->path);
2393 	}
2394 
2395 	if (unveil(GOT_TMPDIR_STR, "rwc") == -1)
2396 		fatal("unveil %s", GOT_TMPDIR_STR);
2397 
2398 	if (unveil(NULL, NULL) == -1)
2399 		fatal("unveil");
2400 }
2401 
2402 int
2403 main(int argc, char **argv)
2404 {
2405 	const struct got_error *error = NULL;
2406 	int ch, fd = -1, daemonize = 1, verbosity = 0, noaction = 0;
2407 	const char *confpath = GOTD_CONF_PATH;
2408 	char *argv0 = argv[0];
2409 	char title[2048];
2410 	gid_t groups[NGROUPS_MAX];
2411 	int ngroups = NGROUPS_MAX;
2412 	struct passwd *pw = NULL;
2413 	struct group *gr = NULL;
2414 	char *repo_path = NULL;
2415 	enum gotd_procid proc_id = PROC_GOTD;
2416 	struct event evsigint, evsigterm, evsighup, evsigusr1;
2417 	int *pack_fds = NULL, *temp_fds = NULL;
2418 
2419 	log_init(1, LOG_DAEMON); /* Log to stderr until daemonized. */
2420 
2421 	while ((ch = getopt(argc, argv, "Adf:LnP:RvW")) != -1) {
2422 		switch (ch) {
2423 		case 'A':
2424 			proc_id = PROC_AUTH;
2425 			break;
2426 		case 'd':
2427 			daemonize = 0;
2428 			break;
2429 		case 'f':
2430 			confpath = optarg;
2431 			break;
2432 		case 'L':
2433 			proc_id = PROC_LISTEN;
2434 			break;
2435 		case 'n':
2436 			noaction = 1;
2437 			break;
2438 		case 'P':
2439 			repo_path = realpath(optarg, NULL);
2440 			if (repo_path == NULL)
2441 				fatal("realpath '%s'", optarg);
2442 			break;
2443 		case 'R':
2444 			proc_id = PROC_REPO_READ;
2445 			break;
2446 		case 'v':
2447 			if (verbosity < 3)
2448 				verbosity++;
2449 			break;
2450 		case 'W':
2451 			proc_id = PROC_REPO_WRITE;
2452 			break;
2453 		default:
2454 			usage();
2455 		}
2456 	}
2457 
2458 	argc -= optind;
2459 	argv += optind;
2460 
2461 	if (argc != 0)
2462 		usage();
2463 
2464 	/* Require an absolute path in argv[0] for reliable re-exec. */
2465 	if (!got_path_is_absolute(argv0))
2466 		fatalx("bad path \"%s\": must be an absolute path", argv0);
2467 
2468 	if (geteuid() && (proc_id == PROC_GOTD || proc_id == PROC_LISTEN))
2469 		fatalx("need root privileges");
2470 
2471 	log_init(daemonize ? 0 : 1, LOG_DAEMON);
2472 	log_setverbose(verbosity);
2473 
2474 	if (parse_config(confpath, proc_id, &gotd) != 0)
2475 		return 1;
2476 
2477 	gotd.argv0 = argv0;
2478 	gotd.daemonize = daemonize;
2479 	gotd.verbosity = verbosity;
2480 	gotd.confpath = confpath;
2481 
2482 	if (proc_id == PROC_GOTD &&
2483 	    (gotd.nrepos == 0 || TAILQ_EMPTY(&gotd.repos)))
2484 		fatalx("no repository defined in configuration file");
2485 
2486 	pw = getpwnam(gotd.user_name);
2487 	if (pw == NULL)
2488 		fatalx("user %s not found", gotd.user_name);
2489 
2490 	if (pw->pw_uid == 0) {
2491 		fatalx("cannot run %s as %s: the user running %s "
2492 		    "must not be the superuser",
2493 		    getprogname(), pw->pw_name, getprogname());
2494 	}
2495 
2496 	if (getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups) == -1)
2497 		log_warnx("group membership list truncated");
2498 
2499 	gr = match_group(groups, ngroups, gotd.unix_group_name);
2500 	if (gr == NULL) {
2501 		fatalx("cannot start %s: the user running %s "
2502 		    "must be a secondary member of group %s",
2503 		    getprogname(), getprogname(), gotd.unix_group_name);
2504 	}
2505 	if (gr->gr_gid == pw->pw_gid) {
2506 		fatalx("cannot start %s: the user running %s "
2507 		    "must be a secondary member of group %s, but "
2508 		    "%s is the user's primary group",
2509 		    getprogname(), getprogname(), gotd.unix_group_name,
2510 		    gotd.unix_group_name);
2511 	}
2512 
2513 	if (proc_id == PROC_LISTEN &&
2514 	    !got_path_is_absolute(gotd.unix_socket_path))
2515 		fatalx("bad unix socket path \"%s\": must be an absolute path",
2516 		    gotd.unix_socket_path);
2517 
2518 	if (noaction)
2519 		return 0;
2520 
2521 	if (proc_id == PROC_GOTD) {
2522 		gotd.pid = getpid();
2523 		snprintf(title, sizeof(title), "%s", gotd_proc_names[proc_id]);
2524 		start_listener(argv0, confpath, daemonize, verbosity);
2525 		arc4random_buf(&clients_hash_key, sizeof(clients_hash_key));
2526 		if (daemonize && daemon(1, 0) == -1)
2527 			fatal("daemon");
2528 	} else if (proc_id == PROC_LISTEN) {
2529 		snprintf(title, sizeof(title), "%s", gotd_proc_names[proc_id]);
2530 		if (verbosity) {
2531 			log_info("socket: %s", gotd.unix_socket_path);
2532 			log_info("user: %s", pw->pw_name);
2533 			log_info("secondary group: %s", gr->gr_name);
2534 		}
2535 
2536 		fd = unix_socket_listen(gotd.unix_socket_path, pw->pw_uid,
2537 		    gr->gr_gid);
2538 		if (fd == -1) {
2539 			fatal("cannot listen on unix socket %s",
2540 			    gotd.unix_socket_path);
2541 		}
2542 		if (daemonize && daemon(0, 0) == -1)
2543 			fatal("daemon");
2544 	} else if (proc_id == PROC_AUTH) {
2545 		snprintf(title, sizeof(title), "%s %s",
2546 		    gotd_proc_names[proc_id], repo_path);
2547 		if (daemonize && daemon(0, 0) == -1)
2548 			fatal("daemon");
2549 	} else if (proc_id == PROC_REPO_READ || proc_id == PROC_REPO_WRITE) {
2550 		error = got_repo_pack_fds_open(&pack_fds);
2551 		if (error != NULL)
2552 			fatalx("cannot open pack tempfiles: %s", error->msg);
2553 		error = got_repo_temp_fds_open(&temp_fds);
2554 		if (error != NULL)
2555 			fatalx("cannot open pack tempfiles: %s", error->msg);
2556 		if (repo_path == NULL)
2557 			fatalx("repository path not specified");
2558 		snprintf(title, sizeof(title), "%s %s",
2559 		    gotd_proc_names[proc_id], repo_path);
2560 		if (daemonize && daemon(0, 0) == -1)
2561 			fatal("daemon");
2562 	} else
2563 		fatal("invalid process id %d", proc_id);
2564 
2565 	setproctitle("%s", title);
2566 	log_procinit(title);
2567 
2568 	/* Drop root privileges. */
2569 	if (setgid(pw->pw_gid) == -1)
2570 		fatal("setgid %d failed", pw->pw_gid);
2571 	if (setuid(pw->pw_uid) == -1)
2572 		fatal("setuid %d failed", pw->pw_uid);
2573 
2574 	event_init();
2575 
2576 	switch (proc_id) {
2577 	case PROC_GOTD:
2578 #ifndef PROFILE
2579 		if (pledge("stdio rpath wpath cpath proc exec "
2580 		    "sendfd recvfd fattr flock unveil", NULL) == -1)
2581 			err(1, "pledge");
2582 #endif
2583 		break;
2584 	case PROC_LISTEN:
2585 #ifndef PROFILE
2586 		if (pledge("stdio sendfd unix", NULL) == -1)
2587 			err(1, "pledge");
2588 #endif
2589 		listen_main(title, fd);
2590 		/* NOTREACHED */
2591 		break;
2592 	case PROC_AUTH:
2593 #ifndef PROFILE
2594 		if (pledge("stdio getpw recvfd unix unveil", NULL) == -1)
2595 			err(1, "pledge");
2596 #endif
2597 		/*
2598 		 * We need the "unix" pledge promise for getpeername(2) only.
2599 		 * Ensure that AF_UNIX bind(2) cannot be used by revoking all
2600 		 * filesystem access via unveil(2). Access to password database
2601 		 * files will still work since "getpw" bypasses unveil(2).
2602 		 */
2603 		apply_unveil_none();
2604 
2605 		auth_main(title, &gotd.repos, repo_path);
2606 		/* NOTREACHED */
2607 		break;
2608 	case PROC_REPO_READ:
2609 #ifndef PROFILE
2610 		if (pledge("stdio rpath recvfd unveil", NULL) == -1)
2611 			err(1, "pledge");
2612 #endif
2613 		apply_unveil_repo_readonly(repo_path);
2614 		repo_read_main(title, repo_path, pack_fds, temp_fds);
2615 		/* NOTREACHED */
2616 		exit(0);
2617 	case PROC_REPO_WRITE:
2618 #ifndef PROFILE
2619 		if (pledge("stdio rpath recvfd unveil", NULL) == -1)
2620 			err(1, "pledge");
2621 #endif
2622 		apply_unveil_repo_readonly(repo_path);
2623 		repo_write_main(title, repo_path, pack_fds, temp_fds);
2624 		/* NOTREACHED */
2625 		exit(0);
2626 	default:
2627 		fatal("invalid process id %d", proc_id);
2628 	}
2629 
2630 	if (proc_id != PROC_GOTD)
2631 		fatal("invalid process id %d", proc_id);
2632 
2633 	apply_unveil();
2634 
2635 	signal_set(&evsigint, SIGINT, gotd_sighdlr, NULL);
2636 	signal_set(&evsigterm, SIGTERM, gotd_sighdlr, NULL);
2637 	signal_set(&evsighup, SIGHUP, gotd_sighdlr, NULL);
2638 	signal_set(&evsigusr1, SIGUSR1, gotd_sighdlr, NULL);
2639 	signal(SIGPIPE, SIG_IGN);
2640 
2641 	signal_add(&evsigint, NULL);
2642 	signal_add(&evsigterm, NULL);
2643 	signal_add(&evsighup, NULL);
2644 	signal_add(&evsigusr1, NULL);
2645 
2646 	gotd_imsg_event_add(&gotd.listen_proc.iev);
2647 
2648 	event_dispatch();
2649 
2650 	if (pack_fds)
2651 		got_repo_pack_fds_close(pack_fds);
2652 	free(repo_path);
2653 	return 0;
2654 }