2 * Copyright (c) 2010 - 2016 Reyk Floeter <reyk@openbsd.org>
3 * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 #include <sys/types.h>
19 #include <sys/socket.h>
37 #include "got_compat.h"
39 void proc_exec(struct privsep *, struct privsep_proc *, unsigned int,
41 void proc_setup(struct privsep *, struct privsep_proc *, unsigned int);
42 void proc_open(struct privsep *, int, int);
43 void proc_accept(struct privsep *, int, enum privsep_procid,
45 void proc_close(struct privsep *);
46 int proc_ispeer(struct privsep_proc *, unsigned int, enum privsep_procid);
47 void proc_shutdown(struct privsep_proc *);
48 void proc_sig_handler(int, short, void *);
49 int proc_dispatch_null(int, struct privsep_proc *, struct imsg *);
51 enum privsep_procid privsep_process;
54 proc_ispeer(struct privsep_proc *procs, unsigned int nproc,
55 enum privsep_procid type)
59 for (i = 0; i < nproc; i++)
60 if (procs[i].p_id == type)
67 proc_getid(struct privsep_proc *procs, unsigned int nproc,
68 const char *proc_name)
70 struct privsep_proc *p;
73 for (proc = 0; proc < nproc; proc++) {
75 if (strcmp(p->p_title, proc_name))
85 proc_exec(struct privsep *ps, struct privsep_proc *procs, unsigned int nproc,
86 int argc, char **argv)
88 unsigned int proc, nargc, i, proc_i;
90 struct privsep_proc *p;
94 /* Prepare the new process argv. */
95 nargv = calloc(argc + 5, sizeof(char *));
97 fatal("%s: calloc", __func__);
99 /* Copy call argument first. */
101 nargv[nargc++] = argv[0];
103 /* Set process name argument and save the position. */
104 nargv[nargc] = strdup("-P");
105 if (nargv[nargc] == NULL)
106 fatal("%s: strdup", __func__);
111 /* Point process instance arg to stack and copy the original args. */
112 nargv[nargc] = strdup("-I");
113 if (nargv[nargc] == NULL)
114 fatal("%s: strdup", __func__);
116 nargv[nargc++] = num;
117 for (i = 1; i < (unsigned int) argc; i++)
118 nargv[nargc++] = argv[i];
122 for (proc = 0; proc < nproc; proc++) {
125 /* Update args with process title. */
126 nargv[proc_i] = (char *)(uintptr_t)p->p_title;
128 /* Fire children processes. */
129 for (i = 0; i < ps->ps_instances[p->p_id]; i++) {
130 /* Update the process instance number. */
131 snprintf(num, sizeof(num), "%u", i);
133 fd = ps->ps_pipes[p->p_id][i].pp_pipes[PROC_GOTWEBD][0];
134 ps->ps_pipes[p->p_id][i].pp_pipes[PROC_GOTWEBD][0] = -1;
138 fatal("%s: fork", __func__);
141 /* First create a new session */
145 /* Prepare parent socket. */
146 if (fd != PROC_GOTWEBD_SOCK_FILENO) {
147 if (dup2(fd, PROC_GOTWEBD_SOCK_FILENO)
150 } else if (fcntl(fd, F_SETFD, 0) == -1)
153 execvp(argv[0], nargv);
154 fatal("%s: execvp", __func__);
157 /* Close child end. */
168 proc_connect(struct privsep *ps)
171 unsigned int src, dst, inst;
173 /* Don't distribute any sockets if we are not really going to run. */
177 for (dst = 0; dst < PROC_MAX; dst++) {
178 /* We don't communicate with ourselves. */
179 if (dst == PROC_GOTWEBD)
182 for (inst = 0; inst < ps->ps_instances[dst]; inst++) {
183 iev = &ps->ps_ievs[dst][inst];
184 imsg_init(&iev->ibuf, ps->ps_pp->pp_pipes[dst][inst]);
185 event_set(&iev->ev, iev->ibuf.fd, iev->events,
186 iev->handler, iev->data);
187 event_add(&iev->ev, NULL);
191 /* Distribute the socketpair()s for everyone. */
192 for (src = 0; src < PROC_MAX; src++)
193 for (dst = src; dst < PROC_MAX; dst++) {
194 /* Parent already distributed its fds. */
195 if (src == PROC_GOTWEBD || dst == PROC_GOTWEBD)
198 proc_open(ps, src, dst);
203 proc_init(struct privsep *ps, struct privsep_proc *procs, unsigned int nproc,
204 int argc, char **argv, enum privsep_procid proc_id)
206 struct privsep_proc *p = NULL;
207 struct privsep_pipes *pa, *pb;
212 /* Don't initiate anything if we are not really going to run. */
216 if (proc_id == PROC_GOTWEBD) {
217 privsep_process = PROC_GOTWEBD;
218 proc_setup(ps, procs, nproc);
221 * Create the children sockets so we can use them
222 * to distribute the rest of the socketpair()s using
223 * proc_connect() later.
225 for (dst = 0; dst < PROC_MAX; dst++) {
226 /* Don't create socket for ourselves. */
227 if (dst == PROC_GOTWEBD)
230 for (proc = 0; proc < ps->ps_instances[dst]; proc++) {
231 pa = &ps->ps_pipes[PROC_GOTWEBD][0];
232 pb = &ps->ps_pipes[dst][proc];
233 int sock_flags = SOCK_STREAM | SOCK_NONBLOCK;
235 sock_flags |= SOCK_CLOEXEC;
237 if (socketpair(AF_UNIX, sock_flags,
238 PF_UNSPEC, fds) == -1)
239 fatal("%s: socketpair", __func__);
241 pa->pp_pipes[dst][proc] = fds[0];
242 pb->pp_pipes[PROC_GOTWEBD][0] = fds[1];
247 proc_exec(ps, procs, nproc, argc, argv);
251 /* Initialize a child */
252 for (proc = 0; proc < nproc; proc++) {
253 if (procs[proc].p_id != proc_id)
258 if (p == NULL || p->p_init == NULL)
259 fatalx("%s: process %d missing process initialization",
264 fatalx("failed to initiate child process");
268 proc_accept(struct privsep *ps, int fd, enum privsep_procid dst,
271 struct privsep_pipes *pp = ps->ps_pp;
274 if (ps->ps_ievs[dst] == NULL) {
276 log_debug("%s: %s src %d %d to dst %d %d not connected",
277 __func__, ps->ps_title[privsep_process],
278 privsep_process, ps->ps_instance + 1,
285 if (pp->pp_pipes[dst][n] != -1) {
286 log_warnx("%s: duplicated descriptor", __func__);
290 pp->pp_pipes[dst][n] = fd;
292 iev = &ps->ps_ievs[dst][n];
293 imsg_init(&iev->ibuf, fd);
294 event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev->data);
295 event_add(&iev->ev, NULL);
299 proc_setup(struct privsep *ps, struct privsep_proc *procs, unsigned int nproc)
301 unsigned int i, j, src, dst, id;
302 struct privsep_pipes *pp;
304 /* Initialize parent title, ps_instances and procs. */
305 ps->ps_title[PROC_GOTWEBD] = "parent";
307 for (src = 0; src < PROC_MAX; src++)
308 /* Default to 1 process instance */
309 if (ps->ps_instances[src] < 1)
310 ps->ps_instances[src] = 1;
312 for (src = 0; src < nproc; src++) {
313 procs[src].p_ps = ps;
314 if (procs[src].p_cb == NULL)
315 procs[src].p_cb = proc_dispatch_null;
317 id = procs[src].p_id;
318 ps->ps_title[id] = procs[src].p_title;
319 ps->ps_ievs[id] = calloc(ps->ps_instances[id],
320 sizeof(struct imsgev));
321 if (ps->ps_ievs[id] == NULL)
322 fatal("%s: calloc", __func__);
324 /* With this set up, we are ready to call imsg_init(). */
325 for (i = 0; i < ps->ps_instances[id]; i++) {
326 ps->ps_ievs[id][i].handler = proc_dispatch;
327 ps->ps_ievs[id][i].events = EV_READ;
328 ps->ps_ievs[id][i].proc = &procs[src];
329 ps->ps_ievs[id][i].data = &ps->ps_ievs[id][i];
334 * Allocate pipes for all process instances (incl. parent)
336 * - ps->ps_pipes: N:M mapping
337 * N source processes connected to M destination processes:
338 * [src][instances][dst][instances], for example
339 * [PROC_RELAY][3][PROC_CA][3]
341 * - ps->ps_pp: per-process 1:M part of ps->ps_pipes
342 * Each process instance has a destination array of socketpair fds:
343 * [dst][instances], for example
346 for (src = 0; src < PROC_MAX; src++) {
347 /* Allocate destination array for each process */
348 ps->ps_pipes[src] = calloc(ps->ps_instances[src],
349 sizeof(struct privsep_pipes));
350 if (ps->ps_pipes[src] == NULL)
351 fatal("%s: calloc", __func__);
353 for (i = 0; i < ps->ps_instances[src]; i++) {
354 pp = &ps->ps_pipes[src][i];
356 for (dst = 0; dst < PROC_MAX; dst++) {
357 /* Allocate maximum fd integers */
359 calloc(ps->ps_instances[dst],
361 if (pp->pp_pipes[dst] == NULL)
362 fatal("%s: calloc", __func__);
364 /* Mark fd as unused */
365 for (j = 0; j < ps->ps_instances[dst]; j++)
366 pp->pp_pipes[dst][j] = -1;
371 ps->ps_pp = &ps->ps_pipes[privsep_process][ps->ps_instance];
375 proc_kill(struct privsep *ps)
381 if (privsep_process != PROC_GOTWEBD)
387 pid = waitpid(WAIT_ANY, &status, 0);
391 if (WIFSIGNALED(status)) {
392 len = asprintf(&cause, "terminated; signal %d",
394 } else if (WIFEXITED(status)) {
395 if (WEXITSTATUS(status) != 0)
396 len = asprintf(&cause, "exited abnormally");
403 /* child exited OK, don't print a warning message */
404 } else if (len != -1) {
405 log_warnx("lost child: pid %u %s", pid, cause);
408 log_warnx("lost child: pid %u", pid);
409 } while (pid != -1 || (pid == -1 && errno == EINTR));
413 proc_open(struct privsep *ps, int src, int dst)
415 struct privsep_pipes *pa, *pb;
416 struct privsep_fd pf;
420 /* Exchange pipes between process. */
421 for (i = 0; i < ps->ps_instances[src]; i++) {
422 for (j = 0; j < ps->ps_instances[dst]; j++) {
423 /* Don't create sockets for ourself. */
424 if (src == dst && i == j)
427 pa = &ps->ps_pipes[src][i];
428 pb = &ps->ps_pipes[dst][j];
429 int sock_flags = SOCK_STREAM | SOCK_NONBLOCK;
431 sock_flags |= SOCK_CLOEXEC;
433 if (socketpair(AF_UNIX, sock_flags,
434 PF_UNSPEC, fds) == -1)
435 fatal("%s: socketpair", __func__);
437 pa->pp_pipes[dst][j] = fds[0];
438 pb->pp_pipes[src][i] = fds[1];
442 if (proc_compose_imsg(ps, dst, j, IMSG_CTL_PROCFD,
443 -1, pb->pp_pipes[src][i], &pf, sizeof(pf)) == -1)
444 fatal("%s: proc_compose_imsg", __func__);
448 if (proc_compose_imsg(ps, src, i, IMSG_CTL_PROCFD,
449 -1, pa->pp_pipes[dst][j], &pf, sizeof(pf)) == -1)
450 fatal("%s: proc_compose_imsg", __func__);
453 * We have to flush to send the descriptors and close
454 * them to avoid the fd ramp on startup.
456 if (proc_flush_imsg(ps, src, i) == -1 ||
457 proc_flush_imsg(ps, dst, j) == -1)
458 fatal("%s: imsg_flush", __func__);
464 proc_close(struct privsep *ps)
467 struct privsep_pipes *pp;
474 for (dst = 0; dst < PROC_MAX; dst++) {
475 if (ps->ps_ievs[dst] == NULL)
478 for (n = 0; n < ps->ps_instances[dst]; n++) {
479 if (pp->pp_pipes[dst][n] == -1)
482 /* Cancel the fd, close and invalidate the fd */
483 event_del(&(ps->ps_ievs[dst][n].ev));
484 imsg_clear(&(ps->ps_ievs[dst][n].ibuf));
485 close(pp->pp_pipes[dst][n]);
486 pp->pp_pipes[dst][n] = -1;
488 free(ps->ps_ievs[dst]);
493 proc_shutdown(struct privsep_proc *p)
495 struct privsep *ps = p->p_ps;
497 if (p->p_shutdown != NULL)
502 log_info("%s, %s exiting, pid %d", getprogname(), p->p_title, getpid());
508 proc_sig_handler(int sig, short event, void *arg)
510 struct privsep_proc *p = arg;
524 fatalx("proc_sig_handler: unexpected signal");
530 proc_run(struct privsep *ps, struct privsep_proc *p,
531 struct privsep_proc *procs, unsigned int nproc,
532 void (*run)(struct privsep *, struct privsep_proc *, void *), void *arg)
537 log_procinit(p->p_title);
539 /* Set the process group of the current process */
542 /* Use non-standard user */
548 /* Change root directory */
549 if (p->p_chroot != NULL)
554 if (chroot(root) == -1)
555 fatal("proc_run: chroot");
556 if (chdir("/") == -1)
557 fatal("proc_run: chdir(\"/\")");
559 privsep_process = p->p_id;
561 setproctitle("%s", p->p_title);
563 if (setgroups(1, &pw->pw_gid) ||
564 setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
565 setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
566 fatal("proc_run: cannot drop privileges");
570 signal_set(&ps->ps_evsigint, SIGINT, proc_sig_handler, p);
571 signal_set(&ps->ps_evsigterm, SIGTERM, proc_sig_handler, p);
572 signal_set(&ps->ps_evsigchld, SIGCHLD, proc_sig_handler, p);
573 signal_set(&ps->ps_evsighup, SIGHUP, proc_sig_handler, p);
574 signal_set(&ps->ps_evsigpipe, SIGPIPE, proc_sig_handler, p);
575 signal_set(&ps->ps_evsigusr1, SIGUSR1, proc_sig_handler, p);
577 signal_add(&ps->ps_evsigint, NULL);
578 signal_add(&ps->ps_evsigterm, NULL);
579 signal_add(&ps->ps_evsigchld, NULL);
580 signal_add(&ps->ps_evsighup, NULL);
581 signal_add(&ps->ps_evsigpipe, NULL);
582 signal_add(&ps->ps_evsigusr1, NULL);
584 proc_setup(ps, procs, nproc);
585 proc_accept(ps, PROC_GOTWEBD_SOCK_FILENO, PROC_GOTWEBD, 0);
587 DPRINTF("%s: %s %d/%d, pid %d", __func__, p->p_title,
588 ps->ps_instance + 1, ps->ps_instances[p->p_id], getpid());
599 proc_dispatch(int fd, short event, void *arg)
601 struct imsgev *iev = arg;
602 struct privsep_proc *p = iev->proc;
603 struct privsep *ps = p->p_ps;
604 struct imsgbuf *ibuf;
609 struct privsep_fd pf;
611 title = ps->ps_title[privsep_process];
614 if (event & EV_READ) {
616 if (n == -1 && errno != EAGAIN)
617 fatal("%s: imsg_read", __func__);
619 /* this pipe is dead, so remove the event handler */
621 event_loopexit(NULL);
626 if (event & EV_WRITE) {
627 n = msgbuf_write(&ibuf->w);
628 if (n == -1 && errno != EAGAIN)
629 fatal("%s: msgbuf_write", __func__);
631 /* this pipe is dead, so remove the event handler */
633 event_loopexit(NULL);
639 n = imsg_get(ibuf, &imsg);
641 fatal("%s: imsg_get", __func__);
646 log_debug("%s: %s %d got imsg %d peerid %d from %s %d",
647 __func__, title, ps->ps_instance + 1,
648 imsg.hdr.type, imsg.hdr.peerid, p->p_title, imsg.hdr.pid);
652 * Check the message with the program callback
654 if ((p->p_cb)(fd, p, &imsg) == 0) {
655 /* Message was handled by the callback, continue */
661 * Generic message handling
663 switch (imsg.hdr.type) {
664 case IMSG_CTL_VERBOSE:
665 log_info("%s", __func__);
666 IMSG_SIZE_CHECK(&imsg, &verbose);
667 memcpy(&verbose, imsg.data, sizeof(verbose));
668 log_setverbose(verbose);
670 case IMSG_CTL_PROCFD:
671 IMSG_SIZE_CHECK(&imsg, &pf);
672 memcpy(&pf, imsg.data, sizeof(pf));
673 proc_accept(ps, imsg.fd, pf.pf_procid,
677 log_warnx("%s: %s %d got invalid imsg %d peerid %d "
679 __func__, title, ps->ps_instance + 1,
680 imsg.hdr.type, imsg.hdr.peerid,
681 p->p_title, imsg.hdr.pid);
689 proc_dispatch_null(int fd, struct privsep_proc *p, struct imsg *imsg)
695 * imsg helper functions
699 imsg_event_add(struct imsgev *iev)
701 if (iev->handler == NULL) {
702 imsg_flush(&iev->ibuf);
706 iev->events = EV_READ;
707 if (iev->ibuf.w.queued)
708 iev->events |= EV_WRITE;
711 event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev->data);
712 event_add(&iev->ev, NULL);
716 imsg_compose_event(struct imsgev *iev, uint16_t type, uint32_t peerid,
717 pid_t pid, int fd, void *data, uint16_t datalen)
721 ret = imsg_compose(&iev->ibuf, type, peerid, pid, fd, data, datalen);
729 imsg_composev_event(struct imsgev *iev, uint16_t type, uint32_t peerid,
730 pid_t pid, int fd, const struct iovec *iov, int iovcnt)
734 ret = imsg_composev(&iev->ibuf, type, peerid, pid, fd, iov, iovcnt);
742 proc_range(struct privsep *ps, enum privsep_procid id, int *n, int *m)
745 /* Use a range of all target instances */
747 *m = ps->ps_instances[id];
749 /* Use only a single slot of the specified peer process */
755 proc_compose_imsg(struct privsep *ps, enum privsep_procid id, int n,
756 uint16_t type, uint32_t peerid, int fd, void *data, uint16_t datalen)
760 proc_range(ps, id, &n, &m);
762 if (imsg_compose_event(&ps->ps_ievs[id][n],
763 type, peerid, ps->ps_instance + 1, fd, data, datalen) == -1)
771 proc_compose(struct privsep *ps, enum privsep_procid id,
772 uint16_t type, void *data, uint16_t datalen)
774 return (proc_compose_imsg(ps, id, -1, type, -1, -1, data, datalen));
778 proc_composev_imsg(struct privsep *ps, enum privsep_procid id, int n,
779 uint16_t type, uint32_t peerid, int fd, const struct iovec *iov, int iovcnt)
783 proc_range(ps, id, &n, &m);
785 if (imsg_composev_event(&ps->ps_ievs[id][n],
786 type, peerid, ps->ps_instance + 1, fd, iov, iovcnt) == -1)
793 proc_composev(struct privsep *ps, enum privsep_procid id,
794 uint16_t type, const struct iovec *iov, int iovcnt)
796 return (proc_composev_imsg(ps, id, -1, type, -1, -1, iov, iovcnt));
800 proc_forward_imsg(struct privsep *ps, struct imsg *imsg,
801 enum privsep_procid id, int n)
803 return (proc_compose_imsg(ps, id, n, imsg->hdr.type,
804 imsg->hdr.peerid, imsg->fd, imsg->data, IMSG_DATA_SIZE(imsg)));
808 proc_ibuf(struct privsep *ps, enum privsep_procid id, int n)
812 proc_range(ps, id, &n, &m);
813 return (&ps->ps_ievs[id][n].ibuf);
817 proc_iev(struct privsep *ps, enum privsep_procid id, int n)
821 proc_range(ps, id, &n, &m);
822 return (&ps->ps_ievs[id][n]);
825 /* This function should only be called with care as it breaks async I/O */
827 proc_flush_imsg(struct privsep *ps, enum privsep_procid id, int n)
829 struct imsgbuf *ibuf;
832 proc_range(ps, id, &n, &m);
834 ibuf = proc_ibuf(ps, id, n);
838 ret = imsg_flush(ibuf);
839 } while (ret == -1 && errno == EAGAIN);
842 imsg_event_add(&ps->ps_ievs[id][n]);