1 /*-
2 * Copyright (c) 2011 James Gritton
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD: stable/10/usr.sbin/jail/command.c 302958 2016-07-17 14:15:08Z jamie $");
29
30 #include <sys/types.h>
31 #include <sys/event.h>
32 #include <sys/mount.h>
33 #include <sys/stat.h>
34 #include <sys/sysctl.h>
35 #include <sys/user.h>
36 #include <sys/wait.h>
37
38 #include <err.h>
39 #include <errno.h>
40 #include <fcntl.h>
41 #include <kvm.h>
42 #include <login_cap.h>
43 #include <paths.h>
44 #include <pwd.h>
45 #include <signal.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 #include <vis.h>
51
52 #include "jailp.h"
53
54 #define DEFAULT_STOP_TIMEOUT 10
55 #define PHASH_SIZE 256
56
57 LIST_HEAD(phhead, phash);
58
59 struct phash {
60 LIST_ENTRY(phash) le;
61 struct cfjail *j;
62 pid_t pid;
63 };
64
65 int paralimit = -1;
66
67 extern char **environ;
68
69 static int run_command(struct cfjail *j);
70 static int add_proc(struct cfjail *j, pid_t pid);
71 static void clear_procs(struct cfjail *j);
72 static struct cfjail *find_proc(pid_t pid);
73 static int term_procs(struct cfjail *j);
74 static int get_user_info(struct cfjail *j, const char *username,
75 const struct passwd **pwdp, login_cap_t **lcapp);
76 static int check_path(struct cfjail *j, const char *pname, const char *path,
77 int isfile, const char *umount_type);
78
79 static struct cfjails sleeping = TAILQ_HEAD_INITIALIZER(sleeping);
80 static struct cfjails runnable = TAILQ_HEAD_INITIALIZER(runnable);
81 static struct cfstring dummystring = { .len = 1 };
82 static struct phhead phash[PHASH_SIZE];
83 static int kq;
84
85 /*
86 * Run the next command associated with a jail.
87 */
88 int
next_command(struct cfjail * j)89 next_command(struct cfjail *j)
90 {
91 enum intparam comparam;
92 int create_failed, stopping;
93
94 if (paralimit == 0) {
95 if (j->flags & JF_FROM_RUNQ)
96 requeue_head(j, &runnable);
97 else
98 requeue(j, &runnable);
99 return 1;
100 }
101 j->flags &= ~JF_FROM_RUNQ;
102 create_failed = (j->flags & (JF_STOP | JF_FAILED)) == JF_FAILED;
103 stopping = (j->flags & JF_STOP) != 0;
104 comparam = *j->comparam;
105 for (;;) {
106 if (j->comstring == NULL) {
107 j->comparam += create_failed ? -1 : 1;
108 switch ((comparam = *j->comparam)) {
109 case IP__NULL:
110 return 0;
111 case IP_MOUNT_DEVFS:
112 if (!bool_param(j->intparams[IP_MOUNT_DEVFS]))
113 continue;
114 j->comstring = &dummystring;
115 break;
116 case IP_MOUNT_FDESCFS:
117 if (!bool_param(j->intparams[IP_MOUNT_FDESCFS]))
118 continue;
119 j->comstring = &dummystring;
120 break;
121 case IP_MOUNT_PROCFS:
122 if (!bool_param(j->intparams[IP_MOUNT_PROCFS]))
123 continue;
124 j->comstring = &dummystring;
125 break;
126 case IP__OP:
127 case IP_STOP_TIMEOUT:
128 j->comstring = &dummystring;
129 break;
130 default:
131 if (j->intparams[comparam] == NULL)
132 continue;
133 j->comstring = create_failed || (stopping &&
134 (j->intparams[comparam]->flags & PF_REV))
135 ? TAILQ_LAST(&j->intparams[comparam]->val,
136 cfstrings)
137 : TAILQ_FIRST(&j->intparams[comparam]->val);
138 }
139 } else {
140 j->comstring = j->comstring == &dummystring ? NULL :
141 create_failed || (stopping &&
142 (j->intparams[comparam]->flags & PF_REV))
143 ? TAILQ_PREV(j->comstring, cfstrings, tq)
144 : TAILQ_NEXT(j->comstring, tq);
145 }
146 if (j->comstring == NULL || j->comstring->len == 0 ||
147 (create_failed && (comparam == IP_EXEC_PRESTART ||
148 comparam == IP_EXEC_START || comparam == IP_COMMAND ||
149 comparam == IP_EXEC_POSTSTART)))
150 continue;
151 switch (run_command(j)) {
152 case -1:
153 failed(j);
154 /* FALLTHROUGH */
155 case 1:
156 return 1;
157 }
158 }
159 }
160
161 /*
162 * Check command exit status
163 */
164 int
finish_command(struct cfjail * j)165 finish_command(struct cfjail *j)
166 {
167 struct cfjail *rj;
168 int error;
169
170 if (!(j->flags & JF_SLEEPQ))
171 return 0;
172 j->flags &= ~JF_SLEEPQ;
173 if (*j->comparam == IP_STOP_TIMEOUT) {
174 j->flags &= ~JF_TIMEOUT;
175 j->pstatus = 0;
176 return 0;
177 }
178 paralimit++;
179 if (!TAILQ_EMPTY(&runnable)) {
180 rj = TAILQ_FIRST(&runnable);
181 rj->flags |= JF_FROM_RUNQ;
182 requeue(rj, &ready);
183 }
184 error = 0;
185 if (j->flags & JF_TIMEOUT) {
186 j->flags &= ~JF_TIMEOUT;
187 if (*j->comparam != IP_STOP_TIMEOUT) {
188 jail_warnx(j, "%s: timed out", j->comline);
189 failed(j);
190 error = -1;
191 } else if (verbose > 0)
192 jail_note(j, "timed out\n");
193 } else if (j->pstatus != 0) {
194 if (WIFSIGNALED(j->pstatus))
195 jail_warnx(j, "%s: exited on signal %d",
196 j->comline, WTERMSIG(j->pstatus));
197 else
198 jail_warnx(j, "%s: failed", j->comline);
199 j->pstatus = 0;
200 failed(j);
201 error = -1;
202 }
203 free(j->comline);
204 j->comline = NULL;
205 return error;
206 }
207
208 /*
209 * Check for finished processes or timeouts.
210 */
211 struct cfjail *
next_proc(int nonblock)212 next_proc(int nonblock)
213 {
214 struct kevent ke;
215 struct timespec ts;
216 struct timespec *tsp;
217 struct cfjail *j;
218
219 if (!TAILQ_EMPTY(&sleeping)) {
220 again:
221 tsp = NULL;
222 if ((j = TAILQ_FIRST(&sleeping)) && j->timeout.tv_sec) {
223 clock_gettime(CLOCK_REALTIME, &ts);
224 ts.tv_sec = j->timeout.tv_sec - ts.tv_sec;
225 ts.tv_nsec = j->timeout.tv_nsec - ts.tv_nsec;
226 if (ts.tv_nsec < 0) {
227 ts.tv_sec--;
228 ts.tv_nsec += 1000000000;
229 }
230 if (ts.tv_sec < 0 ||
231 (ts.tv_sec == 0 && ts.tv_nsec == 0)) {
232 j->flags |= JF_TIMEOUT;
233 clear_procs(j);
234 return j;
235 }
236 tsp = &ts;
237 }
238 if (nonblock) {
239 ts.tv_sec = 0;
240 ts.tv_nsec = 0;
241 tsp = &ts;
242 }
243 switch (kevent(kq, NULL, 0, &ke, 1, tsp)) {
244 case -1:
245 if (errno != EINTR)
246 err(1, "kevent");
247 goto again;
248 case 0:
249 if (!nonblock) {
250 j = TAILQ_FIRST(&sleeping);
251 j->flags |= JF_TIMEOUT;
252 clear_procs(j);
253 return j;
254 }
255 break;
256 case 1:
257 (void)waitpid(ke.ident, NULL, WNOHANG);
258 if ((j = find_proc(ke.ident))) {
259 j->pstatus = ke.data;
260 return j;
261 }
262 goto again;
263 }
264 }
265 return NULL;
266 }
267
268 /*
269 * Run a single command for a jail, possibly inside the jail.
270 */
271 static int
run_command(struct cfjail * j)272 run_command(struct cfjail *j)
273 {
274 const struct passwd *pwd;
275 const struct cfstring *comstring, *s;
276 login_cap_t *lcap;
277 char **argv;
278 char *cs, *comcs, *devpath;
279 const char *jidstr, *conslog, *path, *ruleset, *term, *username;
280 enum intparam comparam;
281 size_t comlen;
282 pid_t pid;
283 int argc, bg, clean, consfd, down, fib, i, injail, sjuser, timeout;
284 #if defined(INET) || defined(INET6)
285 char *addr, *extrap, *p, *val;
286 #endif
287
288 static char *cleanenv;
289
290 /* Perform some operations that aren't actually commands */
291 comparam = *j->comparam;
292 down = j->flags & (JF_STOP | JF_FAILED);
293 switch (comparam) {
294 case IP_STOP_TIMEOUT:
295 return term_procs(j);
296
297 case IP__OP:
298 if (down) {
299 if (jail_remove(j->jid) < 0 && errno == EPERM) {
300 jail_warnx(j, "jail_remove: %s",
301 strerror(errno));
302 return -1;
303 }
304 if (verbose > 0 || (verbose == 0 && (j->flags & JF_STOP
305 ? note_remove : j->name != NULL)))
306 jail_note(j, "removed\n");
307 j->jid = -1;
308 if (j->flags & JF_STOP)
309 dep_done(j, DF_LIGHT);
310 else
311 j->flags &= ~JF_PERSIST;
312 } else {
313 if (create_jail(j) < 0)
314 return -1;
315 if (iflag)
316 printf("%d\n", j->jid);
317 if (verbose >= 0 && (j->name || verbose > 0))
318 jail_note(j, "created\n");
319 dep_done(j, DF_LIGHT);
320 }
321 return 0;
322
323 default: ;
324 }
325 /*
326 * Collect exec arguments. Internal commands for network and
327 * mounting build their own argument lists.
328 */
329 comstring = j->comstring;
330 bg = 0;
331 switch (comparam) {
332 #ifdef INET
333 case IP__IP4_IFADDR:
334 argc = 0;
335 val = alloca(strlen(comstring->s) + 1);
336 strcpy(val, comstring->s);
337 cs = val;
338 extrap = NULL;
339 while ((p = strchr(cs, ' ')) != NULL && strlen(p) > 1) {
340 if (extrap == NULL) {
341 *p = '\0';
342 extrap = p + 1;
343 }
344 cs = p + 1;
345 argc++;
346 }
347
348 argv = alloca((8 + argc) * sizeof(char *));
349 *(const char **)&argv[0] = _PATH_IFCONFIG;
350 if ((cs = strchr(val, '|'))) {
351 argv[1] = alloca(cs - val + 1);
352 strlcpy(argv[1], val, cs - val + 1);
353 addr = cs + 1;
354 } else {
355 *(const char **)&argv[1] =
356 string_param(j->intparams[IP_INTERFACE]);
357 addr = val;
358 }
359 *(const char **)&argv[2] = "inet";
360 if (!(cs = strchr(addr, '/'))) {
361 argv[3] = addr;
362 *(const char **)&argv[4] = "netmask";
363 *(const char **)&argv[5] = "255.255.255.255";
364 argc = 6;
365 } else if (strchr(cs + 1, '.')) {
366 argv[3] = alloca(cs - addr + 1);
367 strlcpy(argv[3], addr, cs - addr + 1);
368 *(const char **)&argv[4] = "netmask";
369 *(const char **)&argv[5] = cs + 1;
370 argc = 6;
371 } else {
372 argv[3] = addr;
373 argc = 4;
374 }
375
376 if (!down) {
377 for (cs = strtok(extrap, " "); cs; cs = strtok(NULL, " ")) {
378 size_t len = strlen(cs) + 1;
379 argv[argc] = alloca(len);
380 strlcpy(argv[argc++], cs, len);
381 }
382 }
383
384 *(const char **)&argv[argc] = down ? "-alias" : "alias";
385 argv[argc + 1] = NULL;
386 break;
387 #endif
388
389 #ifdef INET6
390 case IP__IP6_IFADDR:
391 argc = 0;
392 val = alloca(strlen(comstring->s) + 1);
393 strcpy(val, comstring->s);
394 cs = val;
395 extrap = NULL;
396 while ((p = strchr(cs, ' ')) != NULL && strlen(p) > 1) {
397 if (extrap == NULL) {
398 *p = '\0';
399 extrap = p + 1;
400 }
401 cs = p + 1;
402 argc++;
403 }
404
405 argv = alloca((8 + argc) * sizeof(char *));
406 *(const char **)&argv[0] = _PATH_IFCONFIG;
407 if ((cs = strchr(val, '|'))) {
408 argv[1] = alloca(cs - val + 1);
409 strlcpy(argv[1], val, cs - val + 1);
410 addr = cs + 1;
411 } else {
412 *(const char **)&argv[1] =
413 string_param(j->intparams[IP_INTERFACE]);
414 addr = val;
415 }
416 *(const char **)&argv[2] = "inet6";
417 argv[3] = addr;
418 if (!(cs = strchr(addr, '/'))) {
419 *(const char **)&argv[4] = "prefixlen";
420 *(const char **)&argv[5] = "128";
421 argc = 6;
422 } else
423 argc = 4;
424
425 if (!down) {
426 for (cs = strtok(extrap, " "); cs; cs = strtok(NULL, " ")) {
427 size_t len = strlen(cs) + 1;
428 argv[argc] = alloca(len);
429 strlcpy(argv[argc++], cs, len);
430 }
431 }
432
433 *(const char **)&argv[argc] = down ? "-alias" : "alias";
434 argv[argc + 1] = NULL;
435 break;
436 #endif
437
438 case IP_VNET_INTERFACE:
439 argv = alloca(5 * sizeof(char *));
440 *(const char **)&argv[0] = _PATH_IFCONFIG;
441 argv[1] = comstring->s;
442 *(const char **)&argv[2] = down ? "-vnet" : "vnet";
443 jidstr = string_param(j->intparams[KP_JID]);
444 *(const char **)&argv[3] =
445 jidstr ? jidstr : string_param(j->intparams[KP_NAME]);
446 argv[4] = NULL;
447 break;
448
449 case IP_MOUNT:
450 case IP__MOUNT_FROM_FSTAB:
451 argv = alloca(8 * sizeof(char *));
452 comcs = alloca(comstring->len + 1);
453 strcpy(comcs, comstring->s);
454 argc = 0;
455 for (cs = strtok(comcs, " \t\f\v\r\n"); cs && argc < 4;
456 cs = strtok(NULL, " \t\f\v\r\n")) {
457 if (argc <= 1 && strunvis(cs, cs) < 0) {
458 jail_warnx(j, "%s: %s: fstab parse error",
459 j->intparams[comparam]->name, comstring->s);
460 return -1;
461 }
462 argv[argc++] = cs;
463 }
464 if (argc == 0)
465 return 0;
466 if (argc < 3) {
467 jail_warnx(j, "%s: %s: missing information",
468 j->intparams[comparam]->name, comstring->s);
469 return -1;
470 }
471 if (check_path(j, j->intparams[comparam]->name, argv[1], 0,
472 down ? argv[2] : NULL) < 0)
473 return -1;
474 if (down) {
475 argv[4] = NULL;
476 argv[3] = argv[1];
477 *(const char **)&argv[0] = "/sbin/umount";
478 } else {
479 if (argc == 4) {
480 argv[7] = NULL;
481 argv[6] = argv[1];
482 argv[5] = argv[0];
483 argv[4] = argv[3];
484 *(const char **)&argv[3] = "-o";
485 } else {
486 argv[5] = NULL;
487 argv[4] = argv[1];
488 argv[3] = argv[0];
489 }
490 *(const char **)&argv[0] = _PATH_MOUNT;
491 }
492 *(const char **)&argv[1] = "-t";
493 break;
494
495 case IP_MOUNT_DEVFS:
496 argv = alloca(7 * sizeof(char *));
497 path = string_param(j->intparams[KP_PATH]);
498 if (path == NULL) {
499 jail_warnx(j, "mount.devfs: no path");
500 return -1;
501 }
502 devpath = alloca(strlen(path) + 5);
503 sprintf(devpath, "%s/dev", path);
504 if (check_path(j, "mount.devfs", devpath, 0,
505 down ? "devfs" : NULL) < 0)
506 return -1;
507 if (down) {
508 *(const char **)&argv[0] = "/sbin/umount";
509 argv[1] = devpath;
510 argv[2] = NULL;
511 } else {
512 *(const char **)&argv[0] = _PATH_MOUNT;
513 *(const char **)&argv[1] = "-t";
514 *(const char **)&argv[2] = "devfs";
515 ruleset = string_param(j->intparams[KP_DEVFS_RULESET]);
516 if (!ruleset)
517 ruleset = "4"; /* devfsrules_jail */
518 argv[3] = alloca(11 + strlen(ruleset));
519 sprintf(argv[3], "-oruleset=%s", ruleset);
520 *(const char **)&argv[4] = ".";
521 argv[5] = devpath;
522 argv[6] = NULL;
523 }
524 break;
525
526 case IP_MOUNT_FDESCFS:
527 argv = alloca(7 * sizeof(char *));
528 path = string_param(j->intparams[KP_PATH]);
529 if (path == NULL) {
530 jail_warnx(j, "mount.fdescfs: no path");
531 return -1;
532 }
533 devpath = alloca(strlen(path) + 8);
534 sprintf(devpath, "%s/dev/fd", path);
535 if (check_path(j, "mount.fdescfs", devpath, 0,
536 down ? "fdescfs" : NULL) < 0)
537 return -1;
538 if (down) {
539 *(const char **)&argv[0] = "/sbin/umount";
540 argv[1] = devpath;
541 argv[2] = NULL;
542 } else {
543 *(const char **)&argv[0] = _PATH_MOUNT;
544 *(const char **)&argv[1] = "-t";
545 *(const char **)&argv[2] = "fdescfs";
546 *(const char **)&argv[3] = ".";
547 argv[4] = devpath;
548 argv[5] = NULL;
549 }
550 break;
551
552 case IP_MOUNT_PROCFS:
553 argv = alloca(7 * sizeof(char *));
554 path = string_param(j->intparams[KP_PATH]);
555 if (path == NULL) {
556 jail_warnx(j, "mount.procfs: no path");
557 return -1;
558 }
559 devpath = alloca(strlen(path) + 6);
560 sprintf(devpath, "%s/proc", path);
561 if (check_path(j, "mount.procfs", devpath, 0,
562 down ? "procfs" : NULL) < 0)
563 return -1;
564 if (down) {
565 *(const char **)&argv[0] = "/sbin/umount";
566 argv[1] = devpath;
567 argv[2] = NULL;
568 } else {
569 *(const char **)&argv[0] = _PATH_MOUNT;
570 *(const char **)&argv[1] = "-t";
571 *(const char **)&argv[2] = "procfs";
572 *(const char **)&argv[3] = ".";
573 argv[4] = devpath;
574 argv[5] = NULL;
575 }
576 break;
577
578 case IP_COMMAND:
579 if (j->name != NULL)
580 goto default_command;
581 argc = 0;
582 TAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq)
583 argc++;
584 argv = alloca((argc + 1) * sizeof(char *));
585 argc = 0;
586 TAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq)
587 argv[argc++] = s->s;
588 argv[argc] = NULL;
589 j->comstring = &dummystring;
590 break;
591
592 default:
593 default_command:
594 if ((cs = strpbrk(comstring->s, "!\"$&'()*;<>?[\\]`{|}~")) &&
595 !(cs[0] == '&' && cs[1] == '\0')) {
596 argv = alloca(4 * sizeof(char *));
597 *(const char **)&argv[0] = _PATH_BSHELL;
598 *(const char **)&argv[1] = "-c";
599 argv[2] = comstring->s;
600 argv[3] = NULL;
601 } else {
602 if (cs) {
603 *cs = 0;
604 bg = 1;
605 }
606 comcs = alloca(comstring->len + 1);
607 strcpy(comcs, comstring->s);
608 argc = 0;
609 for (cs = strtok(comcs, " \t\f\v\r\n"); cs;
610 cs = strtok(NULL, " \t\f\v\r\n"))
611 argc++;
612 argv = alloca((argc + 1) * sizeof(char *));
613 strcpy(comcs, comstring->s);
614 argc = 0;
615 for (cs = strtok(comcs, " \t\f\v\r\n"); cs;
616 cs = strtok(NULL, " \t\f\v\r\n"))
617 argv[argc++] = cs;
618 argv[argc] = NULL;
619 }
620 }
621 if (argv[0] == NULL)
622 return 0;
623
624 if (int_param(j->intparams[IP_EXEC_TIMEOUT], &timeout) &&
625 timeout != 0) {
626 clock_gettime(CLOCK_REALTIME, &j->timeout);
627 j->timeout.tv_sec += timeout;
628 } else
629 j->timeout.tv_sec = 0;
630
631 injail = comparam == IP_EXEC_START || comparam == IP_COMMAND ||
632 comparam == IP_EXEC_STOP;
633 clean = bool_param(j->intparams[IP_EXEC_CLEAN]);
634 username = string_param(j->intparams[injail
635 ? IP_EXEC_JAIL_USER : IP_EXEC_SYSTEM_USER]);
636 sjuser = bool_param(j->intparams[IP_EXEC_SYSTEM_JAIL_USER]);
637
638 consfd = 0;
639 if (injail &&
640 (conslog = string_param(j->intparams[IP_EXEC_CONSOLELOG]))) {
641 if (check_path(j, "exec.consolelog", conslog, 1, NULL) < 0)
642 return -1;
643 consfd =
644 open(conslog, O_WRONLY | O_CREAT | O_APPEND, DEFFILEMODE);
645 if (consfd < 0) {
646 jail_warnx(j, "open %s: %s", conslog, strerror(errno));
647 return -1;
648 }
649 }
650
651 comlen = 0;
652 for (i = 0; argv[i]; i++)
653 comlen += strlen(argv[i]) + 1;
654 j->comline = cs = emalloc(comlen);
655 for (i = 0; argv[i]; i++) {
656 strcpy(cs, argv[i]);
657 if (argv[i + 1]) {
658 cs += strlen(argv[i]) + 1;
659 cs[-1] = ' ';
660 }
661 }
662 if (verbose > 0)
663 jail_note(j, "run command%s%s%s: %s\n",
664 injail ? " in jail" : "", username ? " as " : "",
665 username ? username : "", j->comline);
666
667 pid = fork();
668 if (pid < 0)
669 err(1, "fork");
670 if (pid > 0) {
671 if (bg || !add_proc(j, pid)) {
672 free(j->comline);
673 j->comline = NULL;
674 return 0;
675 } else {
676 paralimit--;
677 return 1;
678 }
679 }
680 if (bg)
681 setsid();
682
683 /* Set up the environment and run the command */
684 pwd = NULL;
685 lcap = NULL;
686 if ((clean || username) && injail && sjuser &&
687 get_user_info(j, username, &pwd, &lcap) < 0)
688 exit(1);
689 if (injail) {
690 /* jail_attach won't chdir along with its chroot. */
691 path = string_param(j->intparams[KP_PATH]);
692 if (path && chdir(path) < 0) {
693 jail_warnx(j, "chdir %s: %s", path, strerror(errno));
694 exit(1);
695 }
696 if (int_param(j->intparams[IP_EXEC_FIB], &fib) &&
697 setfib(fib) < 0) {
698 jail_warnx(j, "setfib: %s", strerror(errno));
699 exit(1);
700 }
701 if (jail_attach(j->jid) < 0) {
702 jail_warnx(j, "jail_attach: %s", strerror(errno));
703 exit(1);
704 }
705 }
706 if (clean || username) {
707 if (!(injail && sjuser) &&
708 get_user_info(j, username, &pwd, &lcap) < 0)
709 exit(1);
710 if (clean) {
711 term = getenv("TERM");
712 environ = &cleanenv;
713 setenv("PATH", "/bin:/usr/bin", 0);
714 if (term != NULL)
715 setenv("TERM", term, 1);
716 }
717 if (setgid(pwd->pw_gid) < 0) {
718 jail_warnx(j, "setgid %d: %s", pwd->pw_gid,
719 strerror(errno));
720 exit(1);
721 }
722 if (setusercontext(lcap, pwd, pwd->pw_uid, username
723 ? LOGIN_SETALL & ~LOGIN_SETGROUP & ~LOGIN_SETLOGIN
724 : LOGIN_SETPATH | LOGIN_SETENV) < 0) {
725 jail_warnx(j, "setusercontext %s: %s", pwd->pw_name,
726 strerror(errno));
727 exit(1);
728 }
729 login_close(lcap);
730 setenv("USER", pwd->pw_name, 1);
731 setenv("HOME", pwd->pw_dir, 1);
732 setenv("SHELL",
733 *pwd->pw_shell ? pwd->pw_shell : _PATH_BSHELL, 1);
734 if (clean && chdir(pwd->pw_dir) < 0) {
735 jail_warnx(j, "chdir %s: %s",
736 pwd->pw_dir, strerror(errno));
737 exit(1);
738 }
739 endpwent();
740 }
741
742 if (consfd != 0 && (dup2(consfd, 1) < 0 || dup2(consfd, 2) < 0)) {
743 jail_warnx(j, "exec.consolelog: %s", strerror(errno));
744 exit(1);
745 }
746 closefrom(3);
747 execvp(argv[0], argv);
748 jail_warnx(j, "exec %s: %s", argv[0], strerror(errno));
749 exit(1);
750 }
751
752 /*
753 * Add a process to the hash, tied to a jail.
754 */
755 static int
add_proc(struct cfjail * j,pid_t pid)756 add_proc(struct cfjail *j, pid_t pid)
757 {
758 struct kevent ke;
759 struct cfjail *tj;
760 struct phash *ph;
761
762 if (!kq && (kq = kqueue()) < 0)
763 err(1, "kqueue");
764 EV_SET(&ke, pid, EVFILT_PROC, EV_ADD, NOTE_EXIT, 0, NULL);
765 if (kevent(kq, &ke, 1, NULL, 0, NULL) < 0) {
766 if (errno == ESRCH)
767 return 0;
768 err(1, "kevent");
769 }
770 ph = emalloc(sizeof(struct phash));
771 ph->j = j;
772 ph->pid = pid;
773 LIST_INSERT_HEAD(&phash[pid % PHASH_SIZE], ph, le);
774 j->nprocs++;
775 j->flags |= JF_SLEEPQ;
776 if (j->timeout.tv_sec == 0)
777 requeue(j, &sleeping);
778 else {
779 /* File the jail in the sleep queue according to its timeout. */
780 TAILQ_REMOVE(j->queue, j, tq);
781 TAILQ_FOREACH(tj, &sleeping, tq) {
782 if (!tj->timeout.tv_sec ||
783 j->timeout.tv_sec < tj->timeout.tv_sec ||
784 (j->timeout.tv_sec == tj->timeout.tv_sec &&
785 j->timeout.tv_nsec <= tj->timeout.tv_nsec)) {
786 TAILQ_INSERT_BEFORE(tj, j, tq);
787 break;
788 }
789 }
790 if (tj == NULL)
791 TAILQ_INSERT_TAIL(&sleeping, j, tq);
792 j->queue = &sleeping;
793 }
794 return 1;
795 }
796
797 /*
798 * Remove any processes from the hash that correspond to a jail.
799 */
800 static void
clear_procs(struct cfjail * j)801 clear_procs(struct cfjail *j)
802 {
803 struct kevent ke;
804 struct phash *ph, *tph;
805 int i;
806
807 j->nprocs = 0;
808 for (i = 0; i < PHASH_SIZE; i++)
809 LIST_FOREACH_SAFE(ph, &phash[i], le, tph)
810 if (ph->j == j) {
811 EV_SET(&ke, ph->pid, EVFILT_PROC, EV_DELETE,
812 NOTE_EXIT, 0, NULL);
813 (void)kevent(kq, &ke, 1, NULL, 0, NULL);
814 LIST_REMOVE(ph, le);
815 free(ph);
816 }
817 }
818
819 /*
820 * Find the jail that corresponds to an exited process.
821 */
822 static struct cfjail *
find_proc(pid_t pid)823 find_proc(pid_t pid)
824 {
825 struct cfjail *j;
826 struct phash *ph;
827
828 LIST_FOREACH(ph, &phash[pid % PHASH_SIZE], le)
829 if (ph->pid == pid) {
830 j = ph->j;
831 LIST_REMOVE(ph, le);
832 free(ph);
833 return --j->nprocs ? NULL : j;
834 }
835 return NULL;
836 }
837
838 /*
839 * Send SIGTERM to all processes in a jail and wait for them to die.
840 */
841 static int
term_procs(struct cfjail * j)842 term_procs(struct cfjail *j)
843 {
844 struct kinfo_proc *ki;
845 int i, noted, pcnt, timeout;
846
847 static kvm_t *kd;
848
849 if (!int_param(j->intparams[IP_STOP_TIMEOUT], &timeout))
850 timeout = DEFAULT_STOP_TIMEOUT;
851 else if (timeout == 0)
852 return 0;
853
854 if (kd == NULL) {
855 kd = kvm_open(NULL, NULL, NULL, O_RDONLY, NULL);
856 if (kd == NULL)
857 return 0;
858 }
859
860 ki = kvm_getprocs(kd, KERN_PROC_PROC, 0, &pcnt);
861 if (ki == NULL)
862 return 0;
863 noted = 0;
864 for (i = 0; i < pcnt; i++)
865 if (ki[i].ki_jid == j->jid &&
866 kill(ki[i].ki_pid, SIGTERM) == 0) {
867 (void)add_proc(j, ki[i].ki_pid);
868 if (verbose > 0) {
869 if (!noted) {
870 noted = 1;
871 jail_note(j, "sent SIGTERM to:");
872 }
873 printf(" %d", ki[i].ki_pid);
874 }
875 }
876 if (noted)
877 printf("\n");
878 if (j->nprocs > 0) {
879 clock_gettime(CLOCK_REALTIME, &j->timeout);
880 j->timeout.tv_sec += timeout;
881 return 1;
882 }
883 return 0;
884 }
885
886 /*
887 * Look up a user in the passwd and login.conf files.
888 */
889 static int
get_user_info(struct cfjail * j,const char * username,const struct passwd ** pwdp,login_cap_t ** lcapp)890 get_user_info(struct cfjail *j, const char *username,
891 const struct passwd **pwdp, login_cap_t **lcapp)
892 {
893 const struct passwd *pwd;
894
895 errno = 0;
896 *pwdp = pwd = username ? getpwnam(username) : getpwuid(getuid());
897 if (pwd == NULL) {
898 if (errno)
899 jail_warnx(j, "getpwnam%s%s: %s", username ? " " : "",
900 username ? username : "", strerror(errno));
901 else if (username)
902 jail_warnx(j, "%s: no such user", username);
903 else
904 jail_warnx(j, "unknown uid %d", getuid());
905 return -1;
906 }
907 *lcapp = login_getpwclass(pwd);
908 if (*lcapp == NULL) {
909 jail_warnx(j, "getpwclass %s: %s", pwd->pw_name,
910 strerror(errno));
911 return -1;
912 }
913 /* Set the groups while the group file is still available */
914 if (initgroups(pwd->pw_name, pwd->pw_gid) < 0) {
915 jail_warnx(j, "initgroups %s: %s", pwd->pw_name,
916 strerror(errno));
917 return -1;
918 }
919 return 0;
920 }
921
922 /*
923 * Make sure a mount or consolelog path is a valid absolute pathname
924 * with no symlinks.
925 */
926 static int
check_path(struct cfjail * j,const char * pname,const char * path,int isfile,const char * umount_type)927 check_path(struct cfjail *j, const char *pname, const char *path, int isfile,
928 const char *umount_type)
929 {
930 struct stat st, mpst;
931 struct statfs stfs;
932 char *tpath, *p;
933 const char *jailpath;
934 size_t jplen;
935
936 if (path[0] != '/') {
937 jail_warnx(j, "%s: %s: not an absolute pathname",
938 pname, path);
939 return -1;
940 }
941 /*
942 * Only check for symlinks in components below the jail's path,
943 * since that's where the security risk lies.
944 */
945 jailpath = string_param(j->intparams[KP_PATH]);
946 if (jailpath == NULL)
947 jailpath = "";
948 jplen = strlen(jailpath);
949 if (!strncmp(path, jailpath, jplen) && path[jplen] == '/') {
950 tpath = alloca(strlen(path) + 1);
951 strcpy(tpath, path);
952 for (p = tpath + jplen; p != NULL; ) {
953 p = strchr(p + 1, '/');
954 if (p)
955 *p = '\0';
956 if (lstat(tpath, &st) < 0) {
957 if (errno == ENOENT && isfile && !p)
958 break;
959 jail_warnx(j, "%s: %s: %s", pname, tpath,
960 strerror(errno));
961 return -1;
962 }
963 if (S_ISLNK(st.st_mode)) {
964 jail_warnx(j, "%s: %s is a symbolic link",
965 pname, tpath);
966 return -1;
967 }
968 if (p)
969 *p = '/';
970 }
971 }
972 if (umount_type != NULL) {
973 if (stat(path, &st) < 0 || statfs(path, &stfs) < 0) {
974 jail_warnx(j, "%s: %s: %s", pname, path,
975 strerror(errno));
976 return -1;
977 }
978 if (stat(stfs.f_mntonname, &mpst) < 0) {
979 jail_warnx(j, "%s: %s: %s", pname, stfs.f_mntonname,
980 strerror(errno));
981 return -1;
982 }
983 if (st.st_ino != mpst.st_ino) {
984 jail_warnx(j, "%s: %s: not a mount point",
985 pname, path);
986 return -1;
987 }
988 if (strcmp(stfs.f_fstypename, umount_type)) {
989 jail_warnx(j, "%s: %s: not a %s mount",
990 pname, path, umount_type);
991 return -1;
992 }
993 }
994 return 0;
995 }
996