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.
17 #include "got_compat.h"
19 #include <sys/types.h>
20 #include <sys/queue.h>
21 #include <sys/socket.h>
36 void proc_exec(struct privsep
*, struct privsep_proc
*, unsigned int,
38 void proc_setup(struct privsep
*, struct privsep_proc
*, unsigned int);
39 void proc_open(struct privsep
*, int, int);
40 void proc_accept(struct privsep
*, int, enum privsep_procid
,
42 void proc_close(struct privsep
*);
43 void proc_shutdown(struct privsep_proc
*);
44 void proc_sig_handler(int, short, void *);
45 int proc_dispatch_null(int, struct privsep_proc
*, struct imsg
*);
47 enum privsep_procid privsep_process
;
50 proc_getid(struct privsep_proc
*procs
, unsigned int nproc
,
51 const char *proc_name
)
53 struct privsep_proc
*p
;
56 for (proc
= 0; proc
< nproc
; proc
++) {
58 if (strcmp(p
->p_title
, proc_name
))
68 proc_exec(struct privsep
*ps
, struct privsep_proc
*procs
, unsigned int nproc
,
69 int argc
, char **argv
)
71 unsigned int proc
, nargc
, i
, proc_i
;
73 struct privsep_proc
*p
;
77 /* Prepare the new process argv. */
78 nargv
= calloc(argc
+ 5, sizeof(char *));
80 fatal("%s: calloc", __func__
);
82 /* Copy call argument first. */
84 nargv
[nargc
++] = argv
[0];
86 /* Set process name argument and save the position. */
87 nargv
[nargc
] = strdup("-P");
88 if (nargv
[nargc
] == NULL
)
89 fatal("%s: strdup", __func__
);
94 /* Point process instance arg to stack and copy the original args. */
95 nargv
[nargc
] = strdup("-I");
96 if (nargv
[nargc
] == NULL
)
97 fatal("%s: strdup", __func__
);
100 for (i
= 1; i
< (unsigned int) argc
; i
++)
101 nargv
[nargc
++] = argv
[i
];
105 for (proc
= 0; proc
< nproc
; proc
++) {
108 /* Update args with process title. */
109 nargv
[proc_i
] = (char *)(uintptr_t)p
->p_title
;
111 /* Fire children processes. */
112 for (i
= 0; i
< ps
->ps_instances
[p
->p_id
]; i
++) {
113 /* Update the process instance number. */
114 snprintf(num
, sizeof(num
), "%u", i
);
116 fd
= ps
->ps_pipes
[p
->p_id
][i
].pp_pipes
[PROC_GOTWEBD
][0];
117 ps
->ps_pipes
[p
->p_id
][i
].pp_pipes
[PROC_GOTWEBD
][0] = -1;
121 fatal("%s: fork", __func__
);
124 /* First create a new session */
128 /* Prepare parent socket. */
129 if (fd
!= PROC_GOTWEBD_SOCK_FILENO
) {
130 if (dup2(fd
, PROC_GOTWEBD_SOCK_FILENO
)
133 } else if (fcntl(fd
, F_SETFD
, 0) == -1)
136 execvp(argv
[0], nargv
);
137 fatal("%s: execvp", __func__
);
140 /* Close child end. */
151 proc_connect(struct privsep
*ps
)
154 unsigned int src
, dst
, inst
;
156 /* Don't distribute any sockets if we are not really going to run. */
160 for (dst
= 0; dst
< PROC_MAX
; dst
++) {
161 /* We don't communicate with ourselves. */
162 if (dst
== PROC_GOTWEBD
)
165 for (inst
= 0; inst
< ps
->ps_instances
[dst
]; inst
++) {
166 iev
= &ps
->ps_ievs
[dst
][inst
];
167 imsg_init(&iev
->ibuf
, ps
->ps_pp
->pp_pipes
[dst
][inst
]);
168 event_set(&iev
->ev
, iev
->ibuf
.fd
, iev
->events
,
169 iev
->handler
, iev
->data
);
170 event_add(&iev
->ev
, NULL
);
174 /* Distribute the socketpair()s for everyone. */
175 for (src
= 0; src
< PROC_MAX
; src
++)
176 for (dst
= src
; dst
< PROC_MAX
; dst
++) {
177 /* Parent already distributed its fds. */
178 if (src
== PROC_GOTWEBD
|| dst
== PROC_GOTWEBD
)
181 proc_open(ps
, src
, dst
);
186 proc_init(struct privsep
*ps
, struct privsep_proc
*procs
, unsigned int nproc
,
187 int argc
, char **argv
, enum privsep_procid proc_id
)
189 struct privsep_proc
*p
= NULL
;
190 struct privsep_pipes
*pa
, *pb
;
195 /* Don't initiate anything if we are not really going to run. */
199 if (proc_id
== PROC_GOTWEBD
) {
200 privsep_process
= PROC_GOTWEBD
;
201 proc_setup(ps
, procs
, nproc
);
204 * Create the children sockets so we can use them
205 * to distribute the rest of the socketpair()s using
206 * proc_connect() later.
208 for (dst
= 0; dst
< PROC_MAX
; dst
++) {
209 /* Don't create socket for ourselves. */
210 if (dst
== PROC_GOTWEBD
)
213 for (proc
= 0; proc
< ps
->ps_instances
[dst
]; proc
++) {
214 pa
= &ps
->ps_pipes
[PROC_GOTWEBD
][0];
215 pb
= &ps
->ps_pipes
[dst
][proc
];
216 int sock_flags
= SOCK_STREAM
| SOCK_NONBLOCK
;
218 sock_flags
|= SOCK_CLOEXEC
;
220 if (socketpair(AF_UNIX
, sock_flags
,
221 PF_UNSPEC
, fds
) == -1)
222 fatal("%s: socketpair", __func__
);
224 pa
->pp_pipes
[dst
][proc
] = fds
[0];
225 pb
->pp_pipes
[PROC_GOTWEBD
][0] = fds
[1];
230 proc_exec(ps
, procs
, nproc
, argc
, argv
);
234 /* Initialize a child */
235 for (proc
= 0; proc
< nproc
; proc
++) {
236 if (procs
[proc
].p_id
!= proc_id
)
241 if (p
== NULL
|| p
->p_init
== NULL
)
242 fatalx("%s: process %d missing process initialization",
247 fatalx("failed to initiate child process");
251 proc_accept(struct privsep
*ps
, int fd
, enum privsep_procid dst
,
254 struct privsep_pipes
*pp
= ps
->ps_pp
;
257 if (ps
->ps_ievs
[dst
] == NULL
) {
259 log_debug("%s: %s src %d %d to dst %d %d not connected",
260 __func__
, ps
->ps_title
[privsep_process
],
261 privsep_process
, ps
->ps_instance
+ 1,
268 if (pp
->pp_pipes
[dst
][n
] != -1) {
269 log_warnx("%s: duplicated descriptor", __func__
);
273 pp
->pp_pipes
[dst
][n
] = fd
;
275 iev
= &ps
->ps_ievs
[dst
][n
];
276 imsg_init(&iev
->ibuf
, fd
);
277 event_set(&iev
->ev
, iev
->ibuf
.fd
, iev
->events
, iev
->handler
, iev
->data
);
278 event_add(&iev
->ev
, NULL
);
282 proc_setup(struct privsep
*ps
, struct privsep_proc
*procs
, unsigned int nproc
)
284 unsigned int i
, j
, src
, dst
, id
;
285 struct privsep_pipes
*pp
;
287 /* Initialize parent title, ps_instances and procs. */
288 ps
->ps_title
[PROC_GOTWEBD
] = "parent";
290 for (src
= 0; src
< PROC_MAX
; src
++)
291 /* Default to 1 process instance */
292 if (ps
->ps_instances
[src
] < 1)
293 ps
->ps_instances
[src
] = 1;
295 for (src
= 0; src
< nproc
; src
++) {
296 procs
[src
].p_ps
= ps
;
297 if (procs
[src
].p_cb
== NULL
)
298 procs
[src
].p_cb
= proc_dispatch_null
;
300 id
= procs
[src
].p_id
;
301 ps
->ps_title
[id
] = procs
[src
].p_title
;
302 ps
->ps_ievs
[id
] = calloc(ps
->ps_instances
[id
],
303 sizeof(struct imsgev
));
304 if (ps
->ps_ievs
[id
] == NULL
)
305 fatal("%s: calloc", __func__
);
307 /* With this set up, we are ready to call imsg_init(). */
308 for (i
= 0; i
< ps
->ps_instances
[id
]; i
++) {
309 ps
->ps_ievs
[id
][i
].handler
= proc_dispatch
;
310 ps
->ps_ievs
[id
][i
].events
= EV_READ
;
311 ps
->ps_ievs
[id
][i
].proc
= &procs
[src
];
312 ps
->ps_ievs
[id
][i
].data
= &ps
->ps_ievs
[id
][i
];
317 * Allocate pipes for all process instances (incl. parent)
319 * - ps->ps_pipes: N:M mapping
320 * N source processes connected to M destination processes:
321 * [src][instances][dst][instances], for example
322 * [PROC_RELAY][3][PROC_CA][3]
324 * - ps->ps_pp: per-process 1:M part of ps->ps_pipes
325 * Each process instance has a destination array of socketpair fds:
326 * [dst][instances], for example
329 for (src
= 0; src
< PROC_MAX
; src
++) {
330 /* Allocate destination array for each process */
331 ps
->ps_pipes
[src
] = calloc(ps
->ps_instances
[src
],
332 sizeof(struct privsep_pipes
));
333 if (ps
->ps_pipes
[src
] == NULL
)
334 fatal("%s: calloc", __func__
);
336 for (i
= 0; i
< ps
->ps_instances
[src
]; i
++) {
337 pp
= &ps
->ps_pipes
[src
][i
];
339 for (dst
= 0; dst
< PROC_MAX
; dst
++) {
340 /* Allocate maximum fd integers */
342 calloc(ps
->ps_instances
[dst
],
344 if (pp
->pp_pipes
[dst
] == NULL
)
345 fatal("%s: calloc", __func__
);
347 /* Mark fd as unused */
348 for (j
= 0; j
< ps
->ps_instances
[dst
]; j
++)
349 pp
->pp_pipes
[dst
][j
] = -1;
354 ps
->ps_pp
= &ps
->ps_pipes
[privsep_process
][ps
->ps_instance
];
358 proc_kill(struct privsep
*ps
)
364 if (privsep_process
!= PROC_GOTWEBD
)
370 pid
= waitpid(WAIT_ANY
, &status
, 0);
374 if (WIFSIGNALED(status
)) {
375 len
= asprintf(&cause
, "terminated; signal %d",
377 } else if (WIFEXITED(status
)) {
378 if (WEXITSTATUS(status
) != 0)
379 len
= asprintf(&cause
, "exited abnormally");
386 /* child exited OK, don't print a warning message */
387 } else if (len
!= -1) {
388 log_warnx("lost child: pid %u %s", pid
, cause
);
391 log_warnx("lost child: pid %u", pid
);
392 } while (pid
!= -1 || (pid
== -1 && errno
== EINTR
));
396 proc_open(struct privsep
*ps
, int src
, int dst
)
398 struct privsep_pipes
*pa
, *pb
;
399 struct privsep_fd pf
;
403 /* Exchange pipes between process. */
404 for (i
= 0; i
< ps
->ps_instances
[src
]; i
++) {
405 for (j
= 0; j
< ps
->ps_instances
[dst
]; j
++) {
406 /* Don't create sockets for ourself. */
407 if (src
== dst
&& i
== j
)
410 pa
= &ps
->ps_pipes
[src
][i
];
411 pb
= &ps
->ps_pipes
[dst
][j
];
412 int sock_flags
= SOCK_STREAM
| SOCK_NONBLOCK
;
414 sock_flags
|= SOCK_CLOEXEC
;
416 if (socketpair(AF_UNIX
, sock_flags
,
417 PF_UNSPEC
, fds
) == -1)
418 fatal("%s: socketpair", __func__
);
420 pa
->pp_pipes
[dst
][j
] = fds
[0];
421 pb
->pp_pipes
[src
][i
] = fds
[1];
425 if (proc_compose_imsg(ps
, dst
, j
, IMSG_CTL_PROCFD
,
426 -1, pb
->pp_pipes
[src
][i
], &pf
, sizeof(pf
)) == -1)
427 fatal("%s: proc_compose_imsg", __func__
);
431 if (proc_compose_imsg(ps
, src
, i
, IMSG_CTL_PROCFD
,
432 -1, pa
->pp_pipes
[dst
][j
], &pf
, sizeof(pf
)) == -1)
433 fatal("%s: proc_compose_imsg", __func__
);
436 * We have to flush to send the descriptors and close
437 * them to avoid the fd ramp on startup.
439 if (proc_flush_imsg(ps
, src
, i
) == -1 ||
440 proc_flush_imsg(ps
, dst
, j
) == -1)
441 fatal("%s: imsg_flush", __func__
);
447 proc_close(struct privsep
*ps
)
450 struct privsep_pipes
*pp
;
457 for (dst
= 0; dst
< PROC_MAX
; dst
++) {
458 if (ps
->ps_ievs
[dst
] == NULL
)
461 for (n
= 0; n
< ps
->ps_instances
[dst
]; n
++) {
462 if (pp
->pp_pipes
[dst
][n
] == -1)
465 /* Cancel the fd, close and invalidate the fd */
466 event_del(&(ps
->ps_ievs
[dst
][n
].ev
));
467 imsg_clear(&(ps
->ps_ievs
[dst
][n
].ibuf
));
468 close(pp
->pp_pipes
[dst
][n
]);
469 pp
->pp_pipes
[dst
][n
] = -1;
471 free(ps
->ps_ievs
[dst
]);
476 proc_shutdown(struct privsep_proc
*p
)
478 struct privsep
*ps
= p
->p_ps
;
480 if (p
->p_shutdown
!= NULL
)
485 log_info("%s, %s exiting, pid %d", getprogname(), p
->p_title
, getpid());
491 proc_sig_handler(int sig
, short event
, void *arg
)
493 struct privsep_proc
*p
= arg
;
507 fatalx("proc_sig_handler: unexpected signal");
513 proc_run(struct privsep
*ps
, struct privsep_proc
*p
,
514 struct privsep_proc
*procs
, unsigned int nproc
,
515 void (*run
)(struct privsep
*, struct privsep_proc
*, void *), void *arg
)
520 log_procinit(p
->p_title
);
522 /* Set the process group of the current process */
525 /* Use non-standard user */
531 /* Change root directory */
532 if (p
->p_chroot
!= NULL
)
537 if (chroot(root
) == -1)
538 fatal("proc_run: chroot");
539 if (chdir("/") == -1)
540 fatal("proc_run: chdir(\"/\")");
542 privsep_process
= p
->p_id
;
544 setproctitle("%s", p
->p_title
);
546 if (setgroups(1, &pw
->pw_gid
) ||
547 setresgid(pw
->pw_gid
, pw
->pw_gid
, pw
->pw_gid
) ||
548 setresuid(pw
->pw_uid
, pw
->pw_uid
, pw
->pw_uid
))
549 fatal("proc_run: cannot drop privileges");
553 signal_set(&ps
->ps_evsigint
, SIGINT
, proc_sig_handler
, p
);
554 signal_set(&ps
->ps_evsigterm
, SIGTERM
, proc_sig_handler
, p
);
555 signal_set(&ps
->ps_evsigchld
, SIGCHLD
, proc_sig_handler
, p
);
556 signal_set(&ps
->ps_evsighup
, SIGHUP
, proc_sig_handler
, p
);
557 signal_set(&ps
->ps_evsigpipe
, SIGPIPE
, proc_sig_handler
, p
);
558 signal_set(&ps
->ps_evsigusr1
, SIGUSR1
, proc_sig_handler
, p
);
560 signal_add(&ps
->ps_evsigint
, NULL
);
561 signal_add(&ps
->ps_evsigterm
, NULL
);
562 signal_add(&ps
->ps_evsigchld
, NULL
);
563 signal_add(&ps
->ps_evsighup
, NULL
);
564 signal_add(&ps
->ps_evsigpipe
, NULL
);
565 signal_add(&ps
->ps_evsigusr1
, NULL
);
567 proc_setup(ps
, procs
, nproc
);
568 proc_accept(ps
, PROC_GOTWEBD_SOCK_FILENO
, PROC_GOTWEBD
, 0);
570 DPRINTF("%s: %s %d/%d, pid %d", __func__
, p
->p_title
,
571 ps
->ps_instance
+ 1, ps
->ps_instances
[p
->p_id
], getpid());
582 proc_dispatch(int fd
, short event
, void *arg
)
584 struct imsgev
*iev
= arg
;
585 struct privsep_proc
*p
= iev
->proc
;
586 struct privsep
*ps
= p
->p_ps
;
587 struct imsgbuf
*ibuf
;
592 struct privsep_fd pf
;
594 title
= ps
->ps_title
[privsep_process
];
597 if (event
& EV_READ
) {
599 if (n
== -1 && errno
!= EAGAIN
)
600 fatal("%s: imsg_read", __func__
);
602 /* this pipe is dead, so remove the event handler */
604 event_loopexit(NULL
);
609 if (event
& EV_WRITE
) {
610 n
= msgbuf_write(&ibuf
->w
);
611 if (n
== -1 && errno
!= EAGAIN
)
612 fatal("%s: msgbuf_write", __func__
);
614 /* this pipe is dead, so remove the event handler */
616 event_loopexit(NULL
);
622 n
= imsg_get(ibuf
, &imsg
);
624 fatal("%s: imsg_get", __func__
);
629 log_debug("%s: %s %d got imsg %d peerid %d from %s %d",
630 __func__
, title
, ps
->ps_instance
+ 1,
631 imsg
.hdr
.type
, imsg
.hdr
.peerid
, p
->p_title
, imsg
.hdr
.pid
);
635 * Check the message with the program callback
637 if ((p
->p_cb
)(fd
, p
, &imsg
) == 0) {
638 /* Message was handled by the callback, continue */
644 * Generic message handling
646 switch (imsg
.hdr
.type
) {
647 case IMSG_CTL_VERBOSE
:
648 log_info("%s", __func__
);
649 IMSG_SIZE_CHECK(&imsg
, &verbose
);
650 memcpy(&verbose
, imsg
.data
, sizeof(verbose
));
651 log_setverbose(verbose
);
653 case IMSG_CTL_PROCFD
:
654 IMSG_SIZE_CHECK(&imsg
, &pf
);
655 memcpy(&pf
, imsg
.data
, sizeof(pf
));
656 proc_accept(ps
, imsg
.fd
, pf
.pf_procid
,
660 log_warnx("%s: %s %d got invalid imsg %d peerid %d "
662 __func__
, title
, ps
->ps_instance
+ 1,
663 imsg
.hdr
.type
, imsg
.hdr
.peerid
,
664 p
->p_title
, imsg
.hdr
.pid
);
672 proc_dispatch_null(int fd
, struct privsep_proc
*p
, struct imsg
*imsg
)
678 * imsg helper functions
682 imsg_event_add(struct imsgev
*iev
)
684 if (iev
->handler
== NULL
) {
685 imsg_flush(&iev
->ibuf
);
689 iev
->events
= EV_READ
;
690 if (iev
->ibuf
.w
.queued
)
691 iev
->events
|= EV_WRITE
;
694 event_set(&iev
->ev
, iev
->ibuf
.fd
, iev
->events
, iev
->handler
, iev
->data
);
695 event_add(&iev
->ev
, NULL
);
699 imsg_compose_event(struct imsgev
*iev
, uint16_t type
, uint32_t peerid
,
700 pid_t pid
, int fd
, void *data
, uint16_t datalen
)
704 ret
= imsg_compose(&iev
->ibuf
, type
, peerid
, pid
, fd
, data
, datalen
);
712 imsg_composev_event(struct imsgev
*iev
, uint16_t type
, uint32_t peerid
,
713 pid_t pid
, int fd
, const struct iovec
*iov
, int iovcnt
)
717 ret
= imsg_composev(&iev
->ibuf
, type
, peerid
, pid
, fd
, iov
, iovcnt
);
725 proc_range(struct privsep
*ps
, enum privsep_procid id
, int *n
, int *m
)
728 /* Use a range of all target instances */
730 *m
= ps
->ps_instances
[id
];
732 /* Use only a single slot of the specified peer process */
738 proc_compose_imsg(struct privsep
*ps
, enum privsep_procid id
, int n
,
739 uint16_t type
, uint32_t peerid
, int fd
, void *data
, uint16_t datalen
)
743 proc_range(ps
, id
, &n
, &m
);
745 if (imsg_compose_event(&ps
->ps_ievs
[id
][n
],
746 type
, peerid
, ps
->ps_instance
+ 1, fd
, data
, datalen
) == -1)
754 proc_compose(struct privsep
*ps
, enum privsep_procid id
,
755 uint16_t type
, void *data
, uint16_t datalen
)
757 return (proc_compose_imsg(ps
, id
, -1, type
, -1, -1, data
, datalen
));
761 proc_composev_imsg(struct privsep
*ps
, enum privsep_procid id
, int n
,
762 uint16_t type
, uint32_t peerid
, int fd
, const struct iovec
*iov
, int iovcnt
)
766 proc_range(ps
, id
, &n
, &m
);
768 if (imsg_composev_event(&ps
->ps_ievs
[id
][n
],
769 type
, peerid
, ps
->ps_instance
+ 1, fd
, iov
, iovcnt
) == -1)
776 proc_composev(struct privsep
*ps
, enum privsep_procid id
,
777 uint16_t type
, const struct iovec
*iov
, int iovcnt
)
779 return (proc_composev_imsg(ps
, id
, -1, type
, -1, -1, iov
, iovcnt
));
783 proc_forward_imsg(struct privsep
*ps
, struct imsg
*imsg
,
784 enum privsep_procid id
, int n
)
786 return (proc_compose_imsg(ps
, id
, n
, imsg
->hdr
.type
,
787 imsg
->hdr
.peerid
, imsg
->fd
, imsg
->data
, IMSG_DATA_SIZE(imsg
)));
791 proc_ibuf(struct privsep
*ps
, enum privsep_procid id
, int n
)
795 proc_range(ps
, id
, &n
, &m
);
796 return (&ps
->ps_ievs
[id
][n
].ibuf
);
800 proc_iev(struct privsep
*ps
, enum privsep_procid id
, int n
)
804 proc_range(ps
, id
, &n
, &m
);
805 return (&ps
->ps_ievs
[id
][n
]);
808 /* This function should only be called with care as it breaks async I/O */
810 proc_flush_imsg(struct privsep
*ps
, enum privsep_procid id
, int n
)
812 struct imsgbuf
*ibuf
;
815 proc_range(ps
, id
, &n
, &m
);
817 ibuf
= proc_ibuf(ps
, id
, n
);
821 ret
= imsg_flush(ibuf
);
822 } while (ret
== -1 && errno
== EAGAIN
);
825 imsg_event_add(&ps
->ps_ievs
[id
][n
]);