1 /*	$OpenBSD: proc.c,v 1.53 2026/03/02 19:28:01 rsadowski Exp $	*/
2 
3 /*
4  * Copyright (c) 2010 - 2016 Reyk Floeter <reyk@openbsd.org>
5  * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <sys/types.h>
21 #include <sys/queue.h>
22 #include <sys/socket.h>
23 #include <sys/wait.h>
24 
25 #include <fcntl.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <unistd.h>
29 #include <string.h>
30 #include <errno.h>
31 #include <signal.h>
32 #include <paths.h>
33 #include <pwd.h>
34 #include <event.h>
35 #include <imsg.h>
36 
37 #include "relayd.h"
38 #include "log.h"
39 
40 void	 proc_exec(struct privsep *, struct privsep_proc *, unsigned int, int,
41 	    char **);
42 void	 proc_setup(struct privsep *, struct privsep_proc *, unsigned int);
43 void	 proc_open(struct privsep *, int, int);
44 void	 proc_accept(struct privsep *, int, enum privsep_procid,
45 	    unsigned int);
46 void	 proc_close(struct privsep *);
47 void	 proc_shutdown(struct privsep_proc *);
48 void	 proc_sig_handler(int, short, void *);
49 void	 proc_range(struct privsep *, enum privsep_procid, int *, int *);
50 int	 proc_dispatch_null(int, struct privsep_proc *, struct imsg *);
51 
52 enum privsep_procid
53 proc_getid(struct privsep_proc *procs, unsigned int nproc,
54     const char *proc_name)
55 {
56 	struct privsep_proc	*p;
57 	unsigned int		 proc;
58 
59 	for (proc = 0; proc < nproc; proc++) {
60 		p = &procs[proc];
61 		if (strcmp(p->p_title, proc_name))
62 			continue;
63 
64 		return (p->p_id);
65 	}
66 
67 	return (PROC_MAX);
68 }
69 
70 void
71 proc_exec(struct privsep *ps, struct privsep_proc *procs, unsigned int nproc,
72     int argc, char **argv)
73 {
74 	unsigned int		 proc, nargc, i, proc_i;
75 	char			**nargv;
76 	struct privsep_proc	*p;
77 	char			 num[32];
78 	int			 fd;
79 
80 	/* Prepare the new process argv. */
81 	nargv = calloc(argc + 5, sizeof(char *));
82 	if (nargv == NULL)
83 		fatal("%s: calloc", __func__);
84 
85 	/* Copy call argument first. */
86 	nargc = 0;
87 	nargv[nargc++] = argv[0];
88 
89 	/* Set process name argument and save the position. */
90 	nargv[nargc++] = "-P";
91 	proc_i = nargc;
92 	nargc++;
93 
94 	/* Point process instance arg to stack and copy the original args. */
95 	nargv[nargc++] = "-I";
96 	nargv[nargc++] = num;
97 	for (i = 1; i < (unsigned int) argc; i++)
98 		nargv[nargc++] = argv[i];
99 
100 	nargv[nargc] = NULL;
101 
102 	for (proc = 0; proc < nproc; proc++) {
103 		p = &procs[proc];
104 
105 		/* Update args with process title. */
106 		nargv[proc_i] = (char *)(uintptr_t)p->p_title;
107 
108 		/* Fire children processes. */
109 		for (i = 0; i < ps->ps_instances[p->p_id]; i++) {
110 			/* Update the process instance number. */
111 			snprintf(num, sizeof(num), "%u", i);
112 
113 			fd = ps->ps_pipes[p->p_id][i].pp_pipes[PROC_PARENT][0];
114 			ps->ps_pipes[p->p_id][i].pp_pipes[PROC_PARENT][0] = -1;
115 
116 			switch (fork()) {
117 			case -1:
118 				fatal("%s: fork", __func__);
119 				break;
120 			case 0:
121 				/* Prepare parent socket. */
122 				if (fd != PROC_PARENT_SOCK_FILENO) {
123 					if (dup2(fd, PROC_PARENT_SOCK_FILENO)
124 					    == -1)
125 						fatal("dup2");
126 				} else if (fcntl(fd, F_SETFD, 0) == -1)
127 					fatal("fcntl");
128 
129 				execvp(argv[0], nargv);
130 				fatal("%s: execvp", __func__);
131 				break;
132 			default:
133 				/* Close child end. */
134 				close(fd);
135 				break;
136 			}
137 		}
138 	}
139 	free(nargv);
140 }
141 
142 void
143 proc_connect(struct privsep *ps)
144 {
145 	struct imsgev		*iev;
146 	unsigned int		 src, dst, inst;
147 
148 	/* Don't distribute any sockets if we are not really going to run. */
149 	if (ps->ps_noaction)
150 		return;
151 
152 	for (dst = 0; dst < PROC_MAX; dst++) {
153 		/* We don't communicate with ourselves. */
154 		if (dst == PROC_PARENT)
155 			continue;
156 
157 		for (inst = 0; inst < ps->ps_instances[dst]; inst++) {
158 			iev = &ps->ps_ievs[dst][inst];
159 			if (imsgbuf_init(&iev->ibuf,
160 			    ps->ps_pp->pp_pipes[dst][inst]) == -1)
161 				fatal("imsgbuf_init");
162 			imsgbuf_allow_fdpass(&iev->ibuf);
163 			event_set(&iev->ev, iev->ibuf.fd, iev->events,
164 			    iev->handler, iev->data);
165 			event_add(&iev->ev, NULL);
166 		}
167 	}
168 
169 	/* Distribute the socketpair()s for everyone. */
170 	for (src = 0; src < PROC_MAX; src++)
171 		for (dst = src; dst < PROC_MAX; dst++) {
172 			/* Parent already distributed its fds. */
173 			if (src == PROC_PARENT || dst == PROC_PARENT)
174 				continue;
175 
176 			proc_open(ps, src, dst);
177 		}
178 }
179 
180 void
181 proc_init(struct privsep *ps, struct privsep_proc *procs, unsigned int nproc,
182     int debug, int argc, char **argv, enum privsep_procid proc_id)
183 {
184 	struct privsep_proc	*p = NULL;
185 	struct privsep_pipes	*pa, *pb;
186 	unsigned int		 proc;
187 	unsigned int		 dst;
188 	int			 fds[2];
189 
190 	/* Don't initiate anything if we are not really going to run. */
191 	if (ps->ps_noaction)
192 		return;
193 
194 	if (proc_id == PROC_PARENT) {
195 		privsep_process = PROC_PARENT;
196 		proc_setup(ps, procs, nproc);
197 
198 		if (!debug && daemon(1, 0) == -1)
199 			fatal("failed to daemonize");
200 
201 		/*
202 		 * Create the children sockets so we can use them
203 		 * to distribute the rest of the socketpair()s using
204 		 * proc_connect() later.
205 		 */
206 		for (dst = 0; dst < PROC_MAX; dst++) {
207 			/* Don't create socket for ourselves. */
208 			if (dst == PROC_PARENT)
209 				continue;
210 
211 			for (proc = 0; proc < ps->ps_instances[dst]; proc++) {
212 				pa = &ps->ps_pipes[PROC_PARENT][0];
213 				pb = &ps->ps_pipes[dst][proc];
214 				if (socketpair(AF_UNIX,
215 				    SOCK_STREAM | SOCK_NONBLOCK | SOCK_CLOEXEC,
216 				    PF_UNSPEC, fds) == -1)
217 					fatal("%s: socketpair", __func__);
218 
219 				pa->pp_pipes[dst][proc] = fds[0];
220 				pb->pp_pipes[PROC_PARENT][0] = fds[1];
221 			}
222 		}
223 
224 		/* Engage! */
225 		proc_exec(ps, procs, nproc, argc, argv);
226 		return;
227 	}
228 
229 	/* Initialize a child */
230 	for (proc = 0; proc < nproc; proc++) {
231 		if (procs[proc].p_id != proc_id)
232 			continue;
233 		p = &procs[proc];
234 		break;
235 	}
236 	if (p == NULL || p->p_init == NULL)
237 		fatalx("%s: process %d missing process initialization",
238 		    __func__, proc_id);
239 
240 	p->p_init(ps, p);
241 
242 	fatalx("failed to initiate child process");
243 }
244 
245 void
246 proc_accept(struct privsep *ps, int fd, enum privsep_procid dst,
247     unsigned int n)
248 {
249 	struct privsep_pipes	*pp = ps->ps_pp;
250 	struct imsgev		*iev;
251 
252 	if (ps->ps_ievs[dst] == NULL) {
253 #if DEBUG > 1
254 		log_debug("%s: %s src %d %d to dst %d %d not connected",
255 		    __func__, ps->ps_title[privsep_process],
256 		    privsep_process, ps->ps_instance + 1,
257 		    dst, n + 1);
258 #endif
259 		close(fd);
260 		return;
261 	}
262 
263 	if (pp->pp_pipes[dst][n] != -1) {
264 		log_warnx("%s: duplicated descriptor", __func__);
265 		close(fd);
266 		return;
267 	} else
268 		pp->pp_pipes[dst][n] = fd;
269 
270 	iev = &ps->ps_ievs[dst][n];
271 	if (imsgbuf_init(&iev->ibuf, fd) == -1)
272 		fatal("imsgbuf_init");
273 	imsgbuf_allow_fdpass(&iev->ibuf);
274 	event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev->data);
275 	event_add(&iev->ev, NULL);
276 }
277 
278 void
279 proc_setup(struct privsep *ps, struct privsep_proc *procs, unsigned int nproc)
280 {
281 	unsigned int		 i, j, src, dst, id;
282 	struct privsep_pipes	*pp;
283 
284 	/* Initialize parent title, ps_instances and procs. */
285 	ps->ps_title[PROC_PARENT] = "parent";
286 
287 	for (src = 0; src < PROC_MAX; src++)
288 		/* Default to 1 process instance */
289 		if (ps->ps_instances[src] < 1)
290 			ps->ps_instances[src] = 1;
291 
292 	for (src = 0; src < nproc; src++) {
293 		procs[src].p_ps = ps;
294 		if (procs[src].p_cb == NULL)
295 			procs[src].p_cb = proc_dispatch_null;
296 
297 		id = procs[src].p_id;
298 		ps->ps_title[id] = procs[src].p_title;
299 		if ((ps->ps_ievs[id] = calloc(ps->ps_instances[id],
300 		    sizeof(struct imsgev))) == NULL)
301 			fatal("%s: calloc", __func__);
302 
303 		/* With this set up, we are ready to call imsgbuf_init(). */
304 		for (i = 0; i < ps->ps_instances[id]; i++) {
305 			ps->ps_ievs[id][i].handler = proc_dispatch;
306 			ps->ps_ievs[id][i].events = EV_READ;
307 			ps->ps_ievs[id][i].proc = &procs[src];
308 			ps->ps_ievs[id][i].data = &ps->ps_ievs[id][i];
309 		}
310 	}
311 
312 	/*
313 	 * Allocate pipes for all process instances (incl. parent)
314 	 *
315 	 * - ps->ps_pipes: N:M mapping
316 	 * N source processes connected to M destination processes:
317 	 * [src][instances][dst][instances], for example
318 	 * [PROC_RELAY][3][PROC_CA][3]
319 	 *
320 	 * - ps->ps_pp: per-process 1:M part of ps->ps_pipes
321 	 * Each process instance has a destination array of socketpair fds:
322 	 * [dst][instances], for example
323 	 * [PROC_PARENT][0]
324 	 */
325 	for (src = 0; src < PROC_MAX; src++) {
326 		/* Allocate destination array for each process */
327 		if ((ps->ps_pipes[src] = calloc(ps->ps_instances[src],
328 		    sizeof(struct privsep_pipes))) == NULL)
329 			fatal("%s: calloc", __func__);
330 
331 		for (i = 0; i < ps->ps_instances[src]; i++) {
332 			pp = &ps->ps_pipes[src][i];
333 
334 			for (dst = 0; dst < PROC_MAX; dst++) {
335 				/* Allocate maximum fd integers */
336 				if ((pp->pp_pipes[dst] =
337 				    calloc(ps->ps_instances[dst],
338 				    sizeof(int))) == NULL)
339 					fatal("%s: calloc", __func__);
340 
341 				/* Mark fd as unused */
342 				for (j = 0; j < ps->ps_instances[dst]; j++)
343 					pp->pp_pipes[dst][j] = -1;
344 			}
345 		}
346 	}
347 
348 	ps->ps_pp = &ps->ps_pipes[privsep_process][ps->ps_instance];
349 }
350 
351 void
352 proc_kill(struct privsep *ps)
353 {
354 	char		*cause;
355 	pid_t		 pid;
356 	int		 len, status;
357 
358 	if (privsep_process != PROC_PARENT)
359 		return;
360 
361 	proc_close(ps);
362 
363 	do {
364 		pid = waitpid(WAIT_ANY, &status, 0);
365 		if (pid <= 0)
366 			continue;
367 
368 		if (WIFSIGNALED(status)) {
369 			len = asprintf(&cause, "terminated; signal %d",
370 			    WTERMSIG(status));
371 		} else if (WIFEXITED(status)) {
372 			if (WEXITSTATUS(status) != 0)
373 				len = asprintf(&cause, "exited abnormally");
374 			else
375 				len = 0;
376 		} else
377 			len = -1;
378 
379 		if (len == 0) {
380 			/* child exited OK, don't print a warning message */
381 		} else if (len != -1) {
382 			log_warnx("lost child: pid %u %s", pid, cause);
383 			free(cause);
384 		} else
385 			log_warnx("lost child: pid %u", pid);
386 	} while (pid != -1 || (pid == -1 && errno == EINTR));
387 }
388 
389 void
390 proc_open(struct privsep *ps, int src, int dst)
391 {
392 	struct privsep_pipes	*pa, *pb;
393 	struct privsep_fd	 pf;
394 	int			 fds[2];
395 	unsigned int		 i, j;
396 
397 	/* Exchange pipes between process. */
398 	for (i = 0; i < ps->ps_instances[src]; i++) {
399 		for (j = 0; j < ps->ps_instances[dst]; j++) {
400 			/* Don't create sockets for ourself. */
401 			if (src == dst && i == j)
402 				continue;
403 
404 			/* No need for CA to CA or RELAY to RELAY sockets. */
405 			if ((src == PROC_CA && dst == PROC_CA) ||
406 			    (src == PROC_RELAY && dst == PROC_RELAY))
407 				continue;
408 
409 			pa = &ps->ps_pipes[src][i];
410 			pb = &ps->ps_pipes[dst][j];
411 			if (socketpair(AF_UNIX,
412 			    SOCK_STREAM | SOCK_NONBLOCK | SOCK_CLOEXEC,
413 			    PF_UNSPEC, fds) == -1)
414 				fatal("%s: socketpair", __func__);
415 
416 			pa->pp_pipes[dst][j] = fds[0];
417 			pb->pp_pipes[src][i] = fds[1];
418 
419 			pf.pf_procid = src;
420 			pf.pf_instance = i;
421 			if (proc_compose_imsg(ps, dst, j, IMSG_CTL_PROCFD,
422 			    -1, pb->pp_pipes[src][i], &pf, sizeof(pf)) == -1)
423 				fatal("%s: proc_compose_imsg", __func__);
424 
425 			pf.pf_procid = dst;
426 			pf.pf_instance = j;
427 			if (proc_compose_imsg(ps, src, i, IMSG_CTL_PROCFD,
428 			    -1, pa->pp_pipes[dst][j], &pf, sizeof(pf)) == -1)
429 				fatal("%s: proc_compose_imsg", __func__);
430 
431 			/*
432 			 * We have to flush to send the descriptors and close
433 			 * them to avoid the fd ramp on startup.
434 			 */
435 			if (proc_flush_imsg(ps, src, i) == -1 ||
436 			    proc_flush_imsg(ps, dst, j) == -1)
437 				fatal("%s: proc_flush_imsg", __func__);
438 		}
439 	}
440 }
441 
442 void
443 proc_close(struct privsep *ps)
444 {
445 	unsigned int		 dst, n;
446 	struct privsep_pipes	*pp;
447 
448 	if (ps == NULL)
449 		return;
450 
451 	pp = ps->ps_pp;
452 
453 	for (dst = 0; dst < PROC_MAX; dst++) {
454 		if (ps->ps_ievs[dst] == NULL)
455 			continue;
456 
457 		for (n = 0; n < ps->ps_instances[dst]; n++) {
458 			if (pp->pp_pipes[dst][n] == -1)
459 				continue;
460 
461 			/* Cancel the fd, close and invalidate the fd */
462 			event_del(&(ps->ps_ievs[dst][n].ev));
463 			imsgbuf_clear(&(ps->ps_ievs[dst][n].ibuf));
464 			close(pp->pp_pipes[dst][n]);
465 			pp->pp_pipes[dst][n] = -1;
466 		}
467 		free(ps->ps_ievs[dst]);
468 	}
469 }
470 
471 void
472 proc_shutdown(struct privsep_proc *p)
473 {
474 	struct privsep	*ps = p->p_ps;
475 
476 	if (p->p_id == PROC_CONTROL && ps)
477 		control_cleanup(&ps->ps_csock);
478 
479 	if (p->p_shutdown != NULL)
480 		(*p->p_shutdown)();
481 
482 	proc_close(ps);
483 
484 	log_info("%s exiting, pid %d", p->p_title, getpid());
485 
486 	exit(0);
487 }
488 
489 void
490 proc_sig_handler(int sig, short event, void *arg)
491 {
492 	struct privsep_proc	*p = arg;
493 
494 	switch (sig) {
495 	case SIGINT:
496 	case SIGTERM:
497 		proc_shutdown(p);
498 		break;
499 	case SIGCHLD:
500 	case SIGHUP:
501 	case SIGPIPE:
502 	case SIGUSR1:
503 		/* ignore */
504 		break;
505 	default:
506 		fatalx("%s: unexpected signal", __func__);
507 		/* NOTREACHED */
508 	}
509 }
510 
511 void
512 proc_run(struct privsep *ps, struct privsep_proc *p,
513     struct privsep_proc *procs, unsigned int nproc,
514     void (*run)(struct privsep *, struct privsep_proc *, void *), void *arg)
515 {
516 	struct passwd		*pw;
517 	const char		*root;
518 	struct control_sock	*rcs;
519 
520 	log_procinit(p->p_title);
521 
522 	if (p->p_id == PROC_CONTROL && ps->ps_instance == 0) {
523 		if (control_init(ps, &ps->ps_csock) == -1)
524 			fatalx("%s: control_init", __func__);
525 		TAILQ_FOREACH(rcs, &ps->ps_rcsocks, cs_entry)
526 			if (control_init(ps, rcs) == -1)
527 				fatalx("%s: control_init", __func__);
528 	}
529 
530 	/* Use non-standard user */
531 	if (p->p_pw != NULL)
532 		pw = p->p_pw;
533 	else
534 		pw = ps->ps_pw;
535 
536 	/* Change root directory */
537 	if (p->p_chroot != NULL)
538 		root = p->p_chroot;
539 	else
540 		root = pw->pw_dir;
541 
542 	if (chroot(root) == -1)
543 		fatal("%s: chroot", __func__);
544 	if (chdir("/") == -1)
545 		fatal("%s: chdir(\"/\")", __func__);
546 
547 	privsep_process = p->p_id;
548 
549 	setproctitle("%s", p->p_title);
550 
551 	if (setgroups(1, &pw->pw_gid) ||
552 	    setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
553 	    setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
554 		fatal("%s: cannot drop privileges", __func__);
555 
556 	event_init();
557 
558 	signal_set(&ps->ps_evsigint, SIGINT, proc_sig_handler, p);
559 	signal_set(&ps->ps_evsigterm, SIGTERM, proc_sig_handler, p);
560 	signal_set(&ps->ps_evsigchld, SIGCHLD, proc_sig_handler, p);
561 	signal_set(&ps->ps_evsighup, SIGHUP, proc_sig_handler, p);
562 	signal_set(&ps->ps_evsigpipe, SIGPIPE, proc_sig_handler, p);
563 	signal_set(&ps->ps_evsigusr1, SIGUSR1, proc_sig_handler, p);
564 
565 	signal_add(&ps->ps_evsigint, NULL);
566 	signal_add(&ps->ps_evsigterm, NULL);
567 	signal_add(&ps->ps_evsigchld, NULL);
568 	signal_add(&ps->ps_evsighup, NULL);
569 	signal_add(&ps->ps_evsigpipe, NULL);
570 	signal_add(&ps->ps_evsigusr1, NULL);
571 
572 	proc_setup(ps, procs, nproc);
573 	proc_accept(ps, PROC_PARENT_SOCK_FILENO, PROC_PARENT, 0);
574 	if (p->p_id == PROC_CONTROL && ps->ps_instance == 0) {
575 		if (control_listen(&ps->ps_csock) == -1)
576 			fatalx("%s: control_listen", __func__);
577 		TAILQ_FOREACH(rcs, &ps->ps_rcsocks, cs_entry)
578 			if (control_listen(rcs) == -1)
579 				fatalx("%s: control_listen", __func__);
580 	}
581 
582 	DPRINTF("%s: %s %d/%d, pid %d", __func__, p->p_title,
583 	    ps->ps_instance + 1, ps->ps_instances[p->p_id], getpid());
584 
585 	if (run != NULL)
586 		run(ps, p, arg);
587 
588 	event_dispatch();
589 
590 	proc_shutdown(p);
591 }
592 
593 void
594 proc_dispatch(int fd, short event, void *arg)
595 {
596 	struct imsgev		*iev = arg;
597 	struct privsep_proc	*p = iev->proc;
598 	struct privsep		*ps = p->p_ps;
599 	struct imsgbuf		*ibuf;
600 	struct imsg		 imsg;
601 	ssize_t			 n;
602 	int			 verbose;
603 	const char		*title;
604 	struct privsep_fd	 pf;
605 
606 	title = ps->ps_title[privsep_process];
607 	ibuf = &iev->ibuf;
608 
609 	if (event & EV_READ) {
610 		if ((n = imsgbuf_read(ibuf)) == -1)
611 			fatal("%s: imsgbuf_read", __func__);
612 		if (n == 0) {
613 			/* this pipe is dead, so remove the event handler */
614 			event_del(&iev->ev);
615 			event_loopexit(NULL);
616 			return;
617 		}
618 	}
619 
620 	if (event & EV_WRITE) {
621 		if (imsgbuf_write(ibuf) == -1) {
622 			if (errno == EPIPE) {
623 				/* this pipe is dead, remove the handler */
624 				event_del(&iev->ev);
625 				event_loopexit(NULL);
626 				return;
627 			}
628 			fatal("%s: imsgbuf_write", __func__);
629 		}
630 	}
631 
632 	for (;;) {
633 		if ((n = imsg_get(ibuf, &imsg)) == -1)
634 			fatal("%s: imsg_get", __func__);
635 		if (n == 0)
636 			break;
637 
638 #if DEBUG > 1
639 		log_debug("%s: %s %d got imsg %d peerid %d from %s %d",
640 		    __func__, title, ps->ps_instance + 1,
641 		    imsg.hdr.type, imsg.hdr.peerid, p->p_title, imsg.hdr.pid);
642 #endif
643 
644 		/*
645 		 * Check the message with the program callback
646 		 */
647 		if ((p->p_cb)(fd, p, &imsg) == 0) {
648 			/* Message was handled by the callback, continue */
649 			imsg_free(&imsg);
650 			continue;
651 		}
652 
653 		/*
654 		 * Generic message handling
655 		 */
656 		switch (imsg.hdr.type) {
657 		case IMSG_CTL_VERBOSE:
658 			IMSG_SIZE_CHECK(&imsg, &verbose);
659 			memcpy(&verbose, imsg.data, sizeof(verbose));
660 			log_setverbose(verbose);
661 			break;
662 		case IMSG_CTL_PROCFD:
663 			IMSG_SIZE_CHECK(&imsg, &pf);
664 			memcpy(&pf, imsg.data, sizeof(pf));
665 			proc_accept(ps, imsg_get_fd(&imsg), pf.pf_procid,
666 			    pf.pf_instance);
667 			break;
668 		default:
669 			fatalx("%s: %s %d got invalid imsg %d peerid %d "
670 			    "from %s %d",
671 			    __func__, title, ps->ps_instance + 1,
672 			    imsg.hdr.type, imsg.hdr.peerid,
673 			    p->p_title, imsg.hdr.pid);
674 		}
675 		imsg_free(&imsg);
676 	}
677 	imsg_event_add(iev);
678 }
679 
680 int
681 proc_dispatch_null(int fd, struct privsep_proc *p, struct imsg *imsg)
682 {
683 	return (-1);
684 }
685 
686 /*
687  * imsg helper functions
688  */
689 
690 void
691 imsg_event_add(struct imsgev *iev)
692 {
693 	if (iev->handler == NULL) {
694 		imsgbuf_flush(&iev->ibuf);
695 		return;
696 	}
697 
698 	iev->events = EV_READ;
699 	if (imsgbuf_queuelen(&iev->ibuf) > 0)
700 		iev->events |= EV_WRITE;
701 
702 	event_del(&iev->ev);
703 	event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev->data);
704 	event_add(&iev->ev, NULL);
705 }
706 
707 int
708 imsg_compose_event(struct imsgev *iev, uint16_t type, uint32_t peerid,
709     pid_t pid, int fd, void *data, uint16_t datalen)
710 {
711 	int	ret;
712 
713 	if ((ret = imsg_compose(&iev->ibuf, type, peerid,
714 	    pid, fd, data, datalen)) == -1)
715 		return (ret);
716 	imsg_event_add(iev);
717 	return (ret);
718 }
719 
720 int
721 imsg_composev_event(struct imsgev *iev, uint16_t type, uint32_t peerid,
722     pid_t pid, int fd, const struct iovec *iov, int iovcnt)
723 {
724 	int	ret;
725 
726 	if ((ret = imsg_composev(&iev->ibuf, type, peerid,
727 	    pid, fd, iov, iovcnt)) == -1)
728 		return (ret);
729 	imsg_event_add(iev);
730 	return (ret);
731 }
732 
733 void
734 proc_range(struct privsep *ps, enum privsep_procid id, int *n, int *m)
735 {
736 	if (*n == -1) {
737 		/* Use a range of all target instances */
738 		*n = 0;
739 		*m = ps->ps_instances[id];
740 	} else {
741 		/* Use only a single slot of the specified peer process */
742 		*m = *n + 1;
743 	}
744 }
745 
746 int
747 proc_compose_imsg(struct privsep *ps, enum privsep_procid id, int n,
748     uint16_t type, uint32_t peerid, int fd, void *data, uint16_t datalen)
749 {
750 	int	 m;
751 
752 	proc_range(ps, id, &n, &m);
753 	for (; n < m; n++) {
754 		if (imsg_compose_event(&ps->ps_ievs[id][n],
755 		    type, peerid, ps->ps_instance + 1, fd, data, datalen) == -1)
756 			return (-1);
757 	}
758 
759 	return (0);
760 }
761 
762 int
763 proc_compose(struct privsep *ps, enum privsep_procid id,
764     uint16_t type, void *data, uint16_t datalen)
765 {
766 	return (proc_compose_imsg(ps, id, -1, type, -1, -1, data, datalen));
767 }
768 
769 int
770 proc_composev_imsg(struct privsep *ps, enum privsep_procid id, int n,
771     uint16_t type, uint32_t peerid, int fd, const struct iovec *iov, int iovcnt)
772 {
773 	int	 m;
774 
775 	proc_range(ps, id, &n, &m);
776 	for (; n < m; n++)
777 		if (imsg_composev_event(&ps->ps_ievs[id][n],
778 		    type, peerid, ps->ps_instance + 1, fd, iov, iovcnt) == -1)
779 			return (-1);
780 
781 	return (0);
782 }
783 
784 int
785 proc_composev(struct privsep *ps, enum privsep_procid id,
786     uint16_t type, const struct iovec *iov, int iovcnt)
787 {
788 	return (proc_composev_imsg(ps, id, -1, type, -1, -1, iov, iovcnt));
789 }
790 
791 int
792 proc_forward_imsg(struct privsep *ps, struct imsg *imsg,
793     enum privsep_procid id, int n)
794 {
795 	return (proc_compose_imsg(ps, id, n, imsg->hdr.type,
796 	    imsg->hdr.peerid, -1, imsg->data, IMSG_DATA_SIZE(imsg)));
797 }
798 
799 struct imsgbuf *
800 proc_ibuf(struct privsep *ps, enum privsep_procid id, int n)
801 {
802 	int	 m;
803 
804 	proc_range(ps, id, &n, &m);
805 	return (&ps->ps_ievs[id][n].ibuf);
806 }
807 
808 struct imsgev *
809 proc_iev(struct privsep *ps, enum privsep_procid id, int n)
810 {
811 	int	 m;
812 
813 	proc_range(ps, id, &n, &m);
814 	return (&ps->ps_ievs[id][n]);
815 }
816 
817 /* This function should only be called with care as it breaks async I/O */
818 int
819 proc_flush_imsg(struct privsep *ps, enum privsep_procid id, int n)
820 {
821 	struct imsgbuf	*ibuf;
822 	int		 m, ret = 0;
823 
824 	proc_range(ps, id, &n, &m);
825 	for (; n < m; n++) {
826 		if ((ibuf = proc_ibuf(ps, id, n)) == NULL)
827 			return (-1);
828 		if ((ret = imsgbuf_flush(ibuf)) == -1)
829 			break;
830 		imsg_event_add(&ps->ps_ievs[id][n]);
831 	}
832 
833 	return (ret);
834 }