1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2011 James Gritton
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD: stable/12/usr.sbin/jail/command.c 372810 2022-12-18 00:34:19Z jamie $");
31
32 #include <sys/types.h>
33 #include <sys/event.h>
34 #include <sys/mount.h>
35 #include <sys/stat.h>
36 #include <sys/sysctl.h>
37 #include <sys/user.h>
38 #include <sys/wait.h>
39
40 #include <err.h>
41 #include <errno.h>
42 #include <fcntl.h>
43 #include <kvm.h>
44 #include <login_cap.h>
45 #include <paths.h>
46 #include <pwd.h>
47 #include <signal.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52 #include <vis.h>
53
54 #include "jailp.h"
55
56 #define DEFAULT_STOP_TIMEOUT 10
57 #define PHASH_SIZE 256
58
59 LIST_HEAD(phhead, phash);
60
61 struct phash {
62 LIST_ENTRY(phash) le;
63 struct cfjail *j;
64 pid_t pid;
65 };
66
67 int paralimit = -1;
68
69 extern char **environ;
70
71 static int run_command(struct cfjail *j);
72 static int add_proc(struct cfjail *j, pid_t pid);
73 static void clear_procs(struct cfjail *j);
74 static struct cfjail *find_proc(pid_t pid);
75 static int term_procs(struct cfjail *j);
76 static int get_user_info(struct cfjail *j, const char *username,
77 const struct passwd **pwdp, login_cap_t **lcapp);
78 static int check_path(struct cfjail *j, const char *pname, const char *path,
79 int isfile, const char *umount_type);
80
81 static struct cfjails sleeping = TAILQ_HEAD_INITIALIZER(sleeping);
82 static struct cfjails runnable = TAILQ_HEAD_INITIALIZER(runnable);
83 static struct cfstring dummystring = { .len = 1 };
84 static struct phhead phash[PHASH_SIZE];
85 static int kq;
86
87 /*
88 * Run the next command associated with a jail.
89 */
90 int
next_command(struct cfjail * j)91 next_command(struct cfjail *j)
92 {
93 enum intparam comparam;
94 int create_failed, stopping;
95
96 if (paralimit == 0) {
97 if (j->flags & JF_FROM_RUNQ)
98 requeue_head(j, &runnable);
99 else
100 requeue(j, &runnable);
101 return 1;
102 }
103 j->flags &= ~JF_FROM_RUNQ;
104 create_failed = (j->flags & (JF_STOP | JF_FAILED)) == JF_FAILED;
105 stopping = (j->flags & JF_STOP) != 0;
106 comparam = *j->comparam;
107 for (;;) {
108 if (j->comstring == NULL) {
109 j->comparam += create_failed ? -1 : 1;
110 switch ((comparam = *j->comparam)) {
111 case IP__NULL:
112 return 0;
113 case IP_MOUNT_DEVFS:
114 if (!bool_param(j->intparams[IP_MOUNT_DEVFS]))
115 continue;
116 j->comstring = &dummystring;
117 break;
118 case IP_MOUNT_FDESCFS:
119 if (!bool_param(j->intparams[IP_MOUNT_FDESCFS]))
120 continue;
121 j->comstring = &dummystring;
122 break;
123 case IP_MOUNT_PROCFS:
124 if (!bool_param(j->intparams[IP_MOUNT_PROCFS]))
125 continue;
126 j->comstring = &dummystring;
127 break;
128 case IP__OP:
129 case IP_STOP_TIMEOUT:
130 j->comstring = &dummystring;
131 break;
132 default:
133 if (j->intparams[comparam] == NULL)
134 continue;
135 j->comstring = create_failed || (stopping &&
136 (j->intparams[comparam]->flags & PF_REV))
137 ? TAILQ_LAST(&j->intparams[comparam]->val,
138 cfstrings)
139 : TAILQ_FIRST(&j->intparams[comparam]->val);
140 }
141 } else {
142 j->comstring = j->comstring == &dummystring ? NULL :
143 create_failed || (stopping &&
144 (j->intparams[comparam]->flags & PF_REV))
145 ? TAILQ_PREV(j->comstring, cfstrings, tq)
146 : TAILQ_NEXT(j->comstring, tq);
147 }
148 if (j->comstring == NULL || j->comstring->len == 0 ||
149 (create_failed && (comparam == IP_EXEC_PRESTART ||
150 comparam == IP_EXEC_CREATED || comparam == IP_EXEC_START ||
151 comparam == IP_COMMAND || comparam == IP_EXEC_POSTSTART ||
152 comparam == IP_EXEC_PREPARE)))
153 continue;
154 switch (run_command(j)) {
155 case -1:
156 failed(j);
157 /* FALLTHROUGH */
158 case 1:
159 return 1;
160 }
161 }
162 }
163
164 /*
165 * Check command exit status
166 */
167 int
finish_command(struct cfjail * j)168 finish_command(struct cfjail *j)
169 {
170 struct cfjail *rj;
171 int error;
172
173 if (!(j->flags & JF_SLEEPQ))
174 return 0;
175 j->flags &= ~JF_SLEEPQ;
176 if (*j->comparam == IP_STOP_TIMEOUT) {
177 j->flags &= ~JF_TIMEOUT;
178 j->pstatus = 0;
179 return 0;
180 }
181 paralimit++;
182 if (!TAILQ_EMPTY(&runnable)) {
183 rj = TAILQ_FIRST(&runnable);
184 rj->flags |= JF_FROM_RUNQ;
185 requeue(rj, &ready);
186 }
187 error = 0;
188 if (j->flags & JF_TIMEOUT) {
189 j->flags &= ~JF_TIMEOUT;
190 if (*j->comparam != IP_STOP_TIMEOUT) {
191 jail_warnx(j, "%s: timed out", j->comline);
192 failed(j);
193 error = -1;
194 } else if (verbose > 0)
195 jail_note(j, "timed out\n");
196 } else if (j->pstatus != 0) {
197 if (WIFSIGNALED(j->pstatus))
198 jail_warnx(j, "%s: exited on signal %d",
199 j->comline, WTERMSIG(j->pstatus));
200 else
201 jail_warnx(j, "%s: failed", j->comline);
202 j->pstatus = 0;
203 failed(j);
204 error = -1;
205 }
206 free(j->comline);
207 j->comline = NULL;
208 return error;
209 }
210
211 /*
212 * Check for finished processes or timeouts.
213 */
214 struct cfjail *
next_proc(int nonblock)215 next_proc(int nonblock)
216 {
217 struct kevent ke;
218 struct timespec ts;
219 struct timespec *tsp;
220 struct cfjail *j;
221
222 if (!TAILQ_EMPTY(&sleeping)) {
223 again:
224 tsp = NULL;
225 if ((j = TAILQ_FIRST(&sleeping)) && j->timeout.tv_sec) {
226 clock_gettime(CLOCK_REALTIME, &ts);
227 ts.tv_sec = j->timeout.tv_sec - ts.tv_sec;
228 ts.tv_nsec = j->timeout.tv_nsec - ts.tv_nsec;
229 if (ts.tv_nsec < 0) {
230 ts.tv_sec--;
231 ts.tv_nsec += 1000000000;
232 }
233 if (ts.tv_sec < 0 ||
234 (ts.tv_sec == 0 && ts.tv_nsec == 0)) {
235 j->flags |= JF_TIMEOUT;
236 clear_procs(j);
237 return j;
238 }
239 tsp = &ts;
240 }
241 if (nonblock) {
242 ts.tv_sec = 0;
243 ts.tv_nsec = 0;
244 tsp = &ts;
245 }
246 switch (kevent(kq, NULL, 0, &ke, 1, tsp)) {
247 case -1:
248 if (errno != EINTR)
249 err(1, "kevent");
250 goto again;
251 case 0:
252 if (!nonblock) {
253 j = TAILQ_FIRST(&sleeping);
254 j->flags |= JF_TIMEOUT;
255 clear_procs(j);
256 return j;
257 }
258 break;
259 case 1:
260 (void)waitpid(ke.ident, NULL, WNOHANG);
261 if ((j = find_proc(ke.ident))) {
262 j->pstatus = ke.data;
263 return j;
264 }
265 goto again;
266 }
267 }
268 return NULL;
269 }
270
271 /*
272 * Run a single command for a jail, possibly inside the jail.
273 */
274 static int
run_command(struct cfjail * j)275 run_command(struct cfjail *j)
276 {
277 const struct passwd *pwd;
278 const struct cfstring *comstring, *s;
279 login_cap_t *lcap;
280 const char **argv;
281 char *acs, *cs, *comcs, *devpath;
282 const char *jidstr, *conslog, *path, *ruleset, *term, *username;
283 enum intparam comparam;
284 size_t comlen;
285 pid_t pid;
286 int argc, bg, clean, consfd, down, fib, i, injail, sjuser, timeout;
287 #if defined(INET) || defined(INET6)
288 char *addr, *extrap, *p, *val;
289 #endif
290
291 static char *cleanenv;
292
293 /* Perform some operations that aren't actually commands */
294 comparam = *j->comparam;
295 down = j->flags & (JF_STOP | JF_FAILED);
296 switch (comparam) {
297 case IP_STOP_TIMEOUT:
298 return term_procs(j);
299
300 case IP__OP:
301 if (down) {
302 if (jail_remove(j->jid) < 0 && errno == EPERM) {
303 jail_warnx(j, "jail_remove: %s",
304 strerror(errno));
305 return -1;
306 }
307 if (verbose > 0 || (verbose == 0 && (j->flags & JF_STOP
308 ? note_remove : j->name != NULL)))
309 jail_note(j, "removed\n");
310 j->jid = -1;
311 if (j->flags & JF_STOP)
312 dep_done(j, DF_LIGHT);
313 else
314 j->flags &= ~JF_PERSIST;
315 } else {
316 if (create_jail(j) < 0)
317 return -1;
318 if (iflag)
319 printf("%d\n", j->jid);
320 if (verbose >= 0 && (j->name || verbose > 0))
321 jail_note(j, "created\n");
322 dep_done(j, DF_LIGHT);
323 }
324 return 0;
325
326 default: ;
327 }
328 /*
329 * Collect exec arguments. Internal commands for network and
330 * mounting build their own argument lists.
331 */
332 comstring = j->comstring;
333 bg = 0;
334 switch (comparam) {
335 #ifdef INET
336 case IP__IP4_IFADDR:
337 argc = 0;
338 val = alloca(strlen(comstring->s) + 1);
339 strcpy(val, comstring->s);
340 cs = val;
341 extrap = NULL;
342 while ((p = strchr(cs, ' ')) != NULL && strlen(p) > 1) {
343 if (extrap == NULL) {
344 *p = '\0';
345 extrap = p + 1;
346 }
347 cs = p + 1;
348 argc++;
349 }
350
351 argv = alloca((8 + argc) * sizeof(char *));
352 argv[0] = _PATH_IFCONFIG;
353 if ((cs = strchr(val, '|'))) {
354 argv[1] = acs = alloca(cs - val + 1);
355 strlcpy(acs, val, cs - val + 1);
356 addr = cs + 1;
357 } else {
358 argv[1] = string_param(j->intparams[IP_INTERFACE]);
359 addr = val;
360 }
361 argv[2] = "inet";
362 if (!(cs = strchr(addr, '/'))) {
363 argv[3] = addr;
364 argv[4] = "netmask";
365 argv[5] = "255.255.255.255";
366 argc = 6;
367 } else if (strchr(cs + 1, '.')) {
368 argv[3] = acs = alloca(cs - addr + 1);
369 strlcpy(acs, addr, cs - addr + 1);
370 argv[4] = "netmask";
371 argv[5] = cs + 1;
372 argc = 6;
373 } else {
374 argv[3] = addr;
375 argc = 4;
376 }
377
378 if (!down && extrap != NULL) {
379 for (cs = strtok(extrap, " "); cs;
380 cs = strtok(NULL, " ")) {
381 size_t len = strlen(cs) + 1;
382 argv[argc++] = acs = alloca(len);
383 strlcpy(acs, cs, len);
384 }
385 }
386
387 argv[argc] = down ? "-alias" : "alias";
388 argv[argc + 1] = NULL;
389 break;
390 #endif
391
392 #ifdef INET6
393 case IP__IP6_IFADDR:
394 argc = 0;
395 val = alloca(strlen(comstring->s) + 1);
396 strcpy(val, comstring->s);
397 cs = val;
398 extrap = NULL;
399 while ((p = strchr(cs, ' ')) != NULL && strlen(p) > 1) {
400 if (extrap == NULL) {
401 *p = '\0';
402 extrap = p + 1;
403 }
404 cs = p + 1;
405 argc++;
406 }
407
408 argv = alloca((8 + argc) * sizeof(char *));
409 argv[0] = _PATH_IFCONFIG;
410 if ((cs = strchr(val, '|'))) {
411 argv[1] = acs = alloca(cs - val + 1);
412 strlcpy(acs, val, cs - val + 1);
413 addr = cs + 1;
414 } else {
415 argv[1] = string_param(j->intparams[IP_INTERFACE]);
416 addr = val;
417 }
418 argv[2] = "inet6";
419 argv[3] = addr;
420 if (!(cs = strchr(addr, '/'))) {
421 argv[4] = "prefixlen";
422 argv[5] = "128";
423 argc = 6;
424 } else
425 argc = 4;
426
427 if (!down && extrap != NULL) {
428 for (cs = strtok(extrap, " "); cs;
429 cs = strtok(NULL, " ")) {
430 size_t len = strlen(cs) + 1;
431 argv[argc++] = acs = alloca(len);
432 strlcpy(acs, cs, len);
433 }
434 }
435
436 argv[argc] = down ? "-alias" : "alias";
437 argv[argc + 1] = NULL;
438 break;
439 #endif
440
441 case IP_VNET_INTERFACE:
442 argv = alloca(5 * sizeof(char *));
443 argv[0] = _PATH_IFCONFIG;
444 argv[1] = comstring->s;
445 argv[2] = down ? "-vnet" : "vnet";
446 jidstr = string_param(j->intparams[KP_JID]);
447 argv[3] = jidstr ? jidstr : string_param(j->intparams[KP_NAME]);
448 argv[4] = NULL;
449 break;
450
451 case IP_MOUNT:
452 case IP__MOUNT_FROM_FSTAB:
453 argv = alloca(8 * sizeof(char *));
454 comcs = alloca(comstring->len + 1);
455 strcpy(comcs, comstring->s);
456 argc = 0;
457 for (cs = strtok(comcs, " \t\f\v\r\n"); cs && argc < 4;
458 cs = strtok(NULL, " \t\f\v\r\n")) {
459 if (argc <= 1 && strunvis(cs, cs) < 0) {
460 jail_warnx(j, "%s: %s: fstab parse error",
461 j->intparams[comparam]->name, comstring->s);
462 return -1;
463 }
464 argv[argc++] = cs;
465 }
466 if (argc == 0)
467 return 0;
468 if (argc < 3) {
469 jail_warnx(j, "%s: %s: missing information",
470 j->intparams[comparam]->name, comstring->s);
471 return -1;
472 }
473 if (check_path(j, j->intparams[comparam]->name, argv[1], 0,
474 down ? argv[2] : NULL) < 0)
475 return -1;
476 if (down) {
477 argv[4] = NULL;
478 argv[3] = argv[1];
479 argv[1] = "-ft";
480 argv[0] = "/sbin/umount";
481 } else {
482 if (argc == 4) {
483 argv[7] = NULL;
484 argv[6] = argv[1];
485 argv[5] = argv[0];
486 argv[4] = argv[3];
487 argv[3] = "-o";
488 } else {
489 argv[5] = NULL;
490 argv[4] = argv[1];
491 argv[3] = argv[0];
492 }
493 argv[1] = "-t";
494 argv[0] = _PATH_MOUNT;
495 }
496 break;
497
498 case IP_MOUNT_DEVFS:
499 argv = alloca(7 * sizeof(char *));
500 path = string_param(j->intparams[KP_PATH]);
501 if (path == NULL) {
502 jail_warnx(j, "mount.devfs: no jail root path defined");
503 return -1;
504 }
505 devpath = alloca(strlen(path) + 5);
506 sprintf(devpath, "%s/dev", path);
507 if (check_path(j, "mount.devfs", devpath, 0,
508 down ? "devfs" : NULL) < 0)
509 return -1;
510 if (down) {
511 argv[0] = "/sbin/umount";
512 argv[1] = devpath;
513 argv[2] = NULL;
514 } else {
515 argv[0] = _PATH_MOUNT;
516 argv[1] = "-t";
517 argv[2] = "devfs";
518 ruleset = string_param(j->intparams[KP_DEVFS_RULESET]);
519 if (!ruleset)
520 ruleset = "4"; /* devfsrules_jail */
521 argv[3] = acs = alloca(11 + strlen(ruleset));
522 sprintf(acs, "-oruleset=%s", ruleset);
523 argv[4] = ".";
524 argv[5] = devpath;
525 argv[6] = NULL;
526 }
527 break;
528
529 case IP_MOUNT_FDESCFS:
530 argv = alloca(7 * sizeof(char *));
531 path = string_param(j->intparams[KP_PATH]);
532 if (path == NULL) {
533 jail_warnx(j, "mount.fdescfs: no jail root path defined");
534 return -1;
535 }
536 devpath = alloca(strlen(path) + 8);
537 sprintf(devpath, "%s/dev/fd", path);
538 if (check_path(j, "mount.fdescfs", devpath, 0,
539 down ? "fdescfs" : NULL) < 0)
540 return -1;
541 if (down) {
542 argv[0] = "/sbin/umount";
543 argv[1] = devpath;
544 argv[2] = NULL;
545 } else {
546 argv[0] = _PATH_MOUNT;
547 argv[1] = "-t";
548 argv[2] = "fdescfs";
549 argv[3] = ".";
550 argv[4] = devpath;
551 argv[5] = NULL;
552 }
553 break;
554
555 case IP_MOUNT_PROCFS:
556 argv = alloca(7 * sizeof(char *));
557 path = string_param(j->intparams[KP_PATH]);
558 if (path == NULL) {
559 jail_warnx(j, "mount.procfs: no jail root path defined");
560 return -1;
561 }
562 devpath = alloca(strlen(path) + 6);
563 sprintf(devpath, "%s/proc", path);
564 if (check_path(j, "mount.procfs", devpath, 0,
565 down ? "procfs" : NULL) < 0)
566 return -1;
567 if (down) {
568 argv[0] = "/sbin/umount";
569 argv[1] = devpath;
570 argv[2] = NULL;
571 } else {
572 argv[0] = _PATH_MOUNT;
573 argv[1] = "-t";
574 argv[2] = "procfs";
575 argv[3] = ".";
576 argv[4] = devpath;
577 argv[5] = NULL;
578 }
579 break;
580
581 case IP_COMMAND:
582 if (j->name != NULL)
583 goto default_command;
584 argc = 0;
585 TAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq)
586 argc++;
587 argv = alloca((argc + 1) * sizeof(char *));
588 argc = 0;
589 TAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq)
590 argv[argc++] = s->s;
591 argv[argc] = NULL;
592 j->comstring = &dummystring;
593 break;
594
595 default:
596 default_command:
597 if ((cs = strpbrk(comstring->s, "!\"$&'()*;<>?[\\]`{|}~")) &&
598 !(cs[0] == '&' && cs[1] == '\0')) {
599 argv = alloca(4 * sizeof(char *));
600 argv[0] = _PATH_BSHELL;
601 argv[1] = "-c";
602 argv[2] = comstring->s;
603 argv[3] = NULL;
604 } else {
605 if (cs) {
606 *cs = 0;
607 bg = 1;
608 }
609 comcs = alloca(comstring->len + 1);
610 strcpy(comcs, comstring->s);
611 argc = 0;
612 for (cs = strtok(comcs, " \t\f\v\r\n"); cs;
613 cs = strtok(NULL, " \t\f\v\r\n"))
614 argc++;
615 argv = alloca((argc + 1) * sizeof(char *));
616 strcpy(comcs, comstring->s);
617 argc = 0;
618 for (cs = strtok(comcs, " \t\f\v\r\n"); cs;
619 cs = strtok(NULL, " \t\f\v\r\n"))
620 argv[argc++] = cs;
621 argv[argc] = NULL;
622 }
623 }
624 if (argv[0] == NULL)
625 return 0;
626
627 if (int_param(j->intparams[IP_EXEC_TIMEOUT], &timeout) &&
628 timeout != 0) {
629 clock_gettime(CLOCK_REALTIME, &j->timeout);
630 j->timeout.tv_sec += timeout;
631 } else
632 j->timeout.tv_sec = 0;
633
634 injail = comparam == IP_EXEC_START || comparam == IP_COMMAND ||
635 comparam == IP_EXEC_STOP;
636 clean = bool_param(j->intparams[IP_EXEC_CLEAN]);
637 username = string_param(j->intparams[injail
638 ? IP_EXEC_JAIL_USER : IP_EXEC_SYSTEM_USER]);
639 sjuser = bool_param(j->intparams[IP_EXEC_SYSTEM_JAIL_USER]);
640
641 consfd = 0;
642 if (injail &&
643 (conslog = string_param(j->intparams[IP_EXEC_CONSOLELOG]))) {
644 if (check_path(j, "exec.consolelog", conslog, 1, NULL) < 0)
645 return -1;
646 consfd =
647 open(conslog, O_WRONLY | O_CREAT | O_APPEND, DEFFILEMODE);
648 if (consfd < 0) {
649 jail_warnx(j, "open %s: %s", conslog, strerror(errno));
650 return -1;
651 }
652 }
653
654 comlen = 0;
655 for (i = 0; argv[i]; i++)
656 comlen += strlen(argv[i]) + 1;
657 j->comline = cs = emalloc(comlen);
658 for (i = 0; argv[i]; i++) {
659 strcpy(cs, argv[i]);
660 if (argv[i + 1]) {
661 cs += strlen(argv[i]) + 1;
662 cs[-1] = ' ';
663 }
664 }
665 if (verbose > 0)
666 jail_note(j, "run command%s%s%s: %s\n",
667 injail ? " in jail" : "", username ? " as " : "",
668 username ? username : "", j->comline);
669
670 pid = fork();
671 if (pid < 0)
672 err(1, "fork");
673 if (pid > 0) {
674 if (bg || !add_proc(j, pid)) {
675 free(j->comline);
676 j->comline = NULL;
677 return 0;
678 } else {
679 paralimit--;
680 return 1;
681 }
682 }
683 if (bg)
684 setsid();
685
686 /* Set up the environment and run the command */
687 pwd = NULL;
688 lcap = NULL;
689 if ((clean || username) && injail && sjuser &&
690 get_user_info(j, username, &pwd, &lcap) < 0)
691 exit(1);
692 if (injail) {
693 /* jail_attach won't chdir along with its chroot. */
694 path = string_param(j->intparams[KP_PATH]);
695 if (path && chdir(path) < 0) {
696 jail_warnx(j, "chdir %s: %s", path, strerror(errno));
697 exit(1);
698 }
699 if (int_param(j->intparams[IP_EXEC_FIB], &fib) &&
700 setfib(fib) < 0) {
701 jail_warnx(j, "setfib: %s", strerror(errno));
702 exit(1);
703 }
704 if (jail_attach(j->jid) < 0) {
705 jail_warnx(j, "jail_attach: %s", strerror(errno));
706 exit(1);
707 }
708 }
709 if (clean || username) {
710 if (!(injail && sjuser) &&
711 get_user_info(j, username, &pwd, &lcap) < 0)
712 exit(1);
713 if (clean) {
714 term = getenv("TERM");
715 environ = &cleanenv;
716 setenv("PATH", "/bin:/usr/bin", 0);
717 if (term != NULL)
718 setenv("TERM", term, 1);
719 }
720 if (setgid(pwd->pw_gid) < 0) {
721 jail_warnx(j, "setgid %d: %s", pwd->pw_gid,
722 strerror(errno));
723 exit(1);
724 }
725 if (setusercontext(lcap, pwd, pwd->pw_uid, username
726 ? LOGIN_SETALL & ~LOGIN_SETGROUP & ~LOGIN_SETLOGIN
727 : LOGIN_SETPATH | LOGIN_SETENV) < 0) {
728 jail_warnx(j, "setusercontext %s: %s", pwd->pw_name,
729 strerror(errno));
730 exit(1);
731 }
732 login_close(lcap);
733 setenv("USER", pwd->pw_name, 1);
734 setenv("HOME", pwd->pw_dir, 1);
735 setenv("SHELL",
736 *pwd->pw_shell ? pwd->pw_shell : _PATH_BSHELL, 1);
737 if (clean && chdir(pwd->pw_dir) < 0) {
738 jail_warnx(j, "chdir %s: %s",
739 pwd->pw_dir, strerror(errno));
740 exit(1);
741 }
742 endpwent();
743 }
744
745 if (consfd != 0 && (dup2(consfd, 1) < 0 || dup2(consfd, 2) < 0)) {
746 jail_warnx(j, "exec.consolelog: %s", strerror(errno));
747 exit(1);
748 }
749 closefrom(3);
750 execvp(argv[0], __DECONST(char *const*, argv));
751 jail_warnx(j, "exec %s: %s", argv[0], strerror(errno));
752 exit(1);
753 }
754
755 /*
756 * Add a process to the hash, tied to a jail.
757 */
758 static int
add_proc(struct cfjail * j,pid_t pid)759 add_proc(struct cfjail *j, pid_t pid)
760 {
761 struct kevent ke;
762 struct cfjail *tj;
763 struct phash *ph;
764
765 if (!kq && (kq = kqueue()) < 0)
766 err(1, "kqueue");
767 EV_SET(&ke, pid, EVFILT_PROC, EV_ADD, NOTE_EXIT, 0, NULL);
768 if (kevent(kq, &ke, 1, NULL, 0, NULL) < 0) {
769 if (errno == ESRCH)
770 return 0;
771 err(1, "kevent");
772 }
773 ph = emalloc(sizeof(struct phash));
774 ph->j = j;
775 ph->pid = pid;
776 LIST_INSERT_HEAD(&phash[pid % PHASH_SIZE], ph, le);
777 j->nprocs++;
778 j->flags |= JF_SLEEPQ;
779 if (j->timeout.tv_sec == 0)
780 requeue(j, &sleeping);
781 else {
782 /* File the jail in the sleep queue according to its timeout. */
783 TAILQ_REMOVE(j->queue, j, tq);
784 TAILQ_FOREACH(tj, &sleeping, tq) {
785 if (!tj->timeout.tv_sec ||
786 j->timeout.tv_sec < tj->timeout.tv_sec ||
787 (j->timeout.tv_sec == tj->timeout.tv_sec &&
788 j->timeout.tv_nsec <= tj->timeout.tv_nsec)) {
789 TAILQ_INSERT_BEFORE(tj, j, tq);
790 break;
791 }
792 }
793 if (tj == NULL)
794 TAILQ_INSERT_TAIL(&sleeping, j, tq);
795 j->queue = &sleeping;
796 }
797 return 1;
798 }
799
800 /*
801 * Remove any processes from the hash that correspond to a jail.
802 */
803 static void
clear_procs(struct cfjail * j)804 clear_procs(struct cfjail *j)
805 {
806 struct kevent ke;
807 struct phash *ph, *tph;
808 int i;
809
810 j->nprocs = 0;
811 for (i = 0; i < PHASH_SIZE; i++)
812 LIST_FOREACH_SAFE(ph, &phash[i], le, tph)
813 if (ph->j == j) {
814 EV_SET(&ke, ph->pid, EVFILT_PROC, EV_DELETE,
815 NOTE_EXIT, 0, NULL);
816 (void)kevent(kq, &ke, 1, NULL, 0, NULL);
817 LIST_REMOVE(ph, le);
818 free(ph);
819 }
820 }
821
822 /*
823 * Find the jail that corresponds to an exited process.
824 */
825 static struct cfjail *
find_proc(pid_t pid)826 find_proc(pid_t pid)
827 {
828 struct cfjail *j;
829 struct phash *ph;
830
831 LIST_FOREACH(ph, &phash[pid % PHASH_SIZE], le)
832 if (ph->pid == pid) {
833 j = ph->j;
834 LIST_REMOVE(ph, le);
835 free(ph);
836 return --j->nprocs ? NULL : j;
837 }
838 return NULL;
839 }
840
841 /*
842 * Send SIGTERM to all processes in a jail and wait for them to die.
843 */
844 static int
term_procs(struct cfjail * j)845 term_procs(struct cfjail *j)
846 {
847 struct kinfo_proc *ki;
848 int i, noted, pcnt, timeout;
849
850 static kvm_t *kd;
851
852 if (!int_param(j->intparams[IP_STOP_TIMEOUT], &timeout))
853 timeout = DEFAULT_STOP_TIMEOUT;
854 else if (timeout == 0)
855 return 0;
856
857 if (kd == NULL) {
858 kd = kvm_open(NULL, NULL, NULL, O_RDONLY, NULL);
859 if (kd == NULL)
860 return 0;
861 }
862
863 ki = kvm_getprocs(kd, KERN_PROC_PROC, 0, &pcnt);
864 if (ki == NULL)
865 return 0;
866 noted = 0;
867 for (i = 0; i < pcnt; i++)
868 if (ki[i].ki_jid == j->jid &&
869 kill(ki[i].ki_pid, SIGTERM) == 0) {
870 (void)add_proc(j, ki[i].ki_pid);
871 if (verbose > 0) {
872 if (!noted) {
873 noted = 1;
874 jail_note(j, "sent SIGTERM to:");
875 }
876 printf(" %d", ki[i].ki_pid);
877 }
878 }
879 if (noted)
880 printf("\n");
881 if (j->nprocs > 0) {
882 clock_gettime(CLOCK_REALTIME, &j->timeout);
883 j->timeout.tv_sec += timeout;
884 return 1;
885 }
886 return 0;
887 }
888
889 /*
890 * Look up a user in the passwd and login.conf files.
891 */
892 static int
get_user_info(struct cfjail * j,const char * username,const struct passwd ** pwdp,login_cap_t ** lcapp)893 get_user_info(struct cfjail *j, const char *username,
894 const struct passwd **pwdp, login_cap_t **lcapp)
895 {
896 const struct passwd *pwd;
897
898 errno = 0;
899 *pwdp = pwd = username ? getpwnam(username) : getpwuid(getuid());
900 if (pwd == NULL) {
901 if (errno)
902 jail_warnx(j, "getpwnam%s%s: %s", username ? " " : "",
903 username ? username : "", strerror(errno));
904 else if (username)
905 jail_warnx(j, "%s: no such user", username);
906 else
907 jail_warnx(j, "unknown uid %d", getuid());
908 return -1;
909 }
910 *lcapp = login_getpwclass(pwd);
911 if (*lcapp == NULL) {
912 jail_warnx(j, "getpwclass %s: %s", pwd->pw_name,
913 strerror(errno));
914 return -1;
915 }
916 /* Set the groups while the group file is still available */
917 if (initgroups(pwd->pw_name, pwd->pw_gid) < 0) {
918 jail_warnx(j, "initgroups %s: %s", pwd->pw_name,
919 strerror(errno));
920 return -1;
921 }
922 return 0;
923 }
924
925 /*
926 * Make sure a mount or consolelog path is a valid absolute pathname
927 * with no symlinks.
928 */
929 static int
check_path(struct cfjail * j,const char * pname,const char * path,int isfile,const char * umount_type)930 check_path(struct cfjail *j, const char *pname, const char *path, int isfile,
931 const char *umount_type)
932 {
933 struct stat st, mpst;
934 struct statfs stfs;
935 char *tpath, *p;
936 const char *jailpath;
937 size_t jplen;
938
939 if (path[0] != '/') {
940 jail_warnx(j, "%s: %s: not an absolute pathname",
941 pname, path);
942 return -1;
943 }
944 /*
945 * Only check for symlinks in components below the jail's path,
946 * since that's where the security risk lies.
947 */
948 jailpath = string_param(j->intparams[KP_PATH]);
949 if (jailpath == NULL)
950 jailpath = "";
951 jplen = strlen(jailpath);
952 if (!strncmp(path, jailpath, jplen) && path[jplen] == '/') {
953 tpath = alloca(strlen(path) + 1);
954 strcpy(tpath, path);
955 for (p = tpath + jplen; p != NULL; ) {
956 p = strchr(p + 1, '/');
957 if (p)
958 *p = '\0';
959 if (lstat(tpath, &st) < 0) {
960 if (errno == ENOENT && isfile && !p)
961 break;
962 jail_warnx(j, "%s: %s: %s", pname, tpath,
963 strerror(errno));
964 return -1;
965 }
966 if (S_ISLNK(st.st_mode)) {
967 jail_warnx(j, "%s: %s is a symbolic link",
968 pname, tpath);
969 return -1;
970 }
971 if (p)
972 *p = '/';
973 }
974 }
975 if (umount_type != NULL) {
976 if (stat(path, &st) < 0 || statfs(path, &stfs) < 0) {
977 jail_warnx(j, "%s: %s: %s", pname, path,
978 strerror(errno));
979 return -1;
980 }
981 if (stat(stfs.f_mntonname, &mpst) < 0) {
982 jail_warnx(j, "%s: %s: %s", pname, stfs.f_mntonname,
983 strerror(errno));
984 return -1;
985 }
986 if (st.st_ino != mpst.st_ino) {
987 jail_warnx(j, "%s: %s: not a mount point",
988 pname, path);
989 return -1;
990 }
991 if (strcmp(stfs.f_fstypename, umount_type)) {
992 jail_warnx(j, "%s: %s: not a %s mount",
993 pname, path, umount_type);
994 return -1;
995 }
996 }
997 return 0;
998 }
999