command.c revision 293290
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 293290 2016-01-07 00:40:51Z bdrewery $");
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
51#include "jailp.h"
52
53#define DEFAULT_STOP_TIMEOUT	10
54#define PHASH_SIZE		256
55
56LIST_HEAD(phhead, phash);
57
58struct phash {
59	LIST_ENTRY(phash)	le;
60	struct cfjail		*j;
61	pid_t			pid;
62};
63
64int paralimit = -1;
65
66extern char **environ;
67
68static int run_command(struct cfjail *j);
69static int add_proc(struct cfjail *j, pid_t pid);
70static void clear_procs(struct cfjail *j);
71static struct cfjail *find_proc(pid_t pid);
72static int term_procs(struct cfjail *j);
73static int get_user_info(struct cfjail *j, const char *username,
74    const struct passwd **pwdp, login_cap_t **lcapp);
75static int check_path(struct cfjail *j, const char *pname, const char *path,
76    int isfile, const char *umount_type);
77
78static struct cfjails sleeping = TAILQ_HEAD_INITIALIZER(sleeping);
79static struct cfjails runnable = TAILQ_HEAD_INITIALIZER(runnable);
80static struct cfstring dummystring = { .len = 1 };
81static struct phhead phash[PHASH_SIZE];
82static int kq;
83
84/*
85 * Run the next command associated with a jail.
86 */
87int
88next_command(struct cfjail *j)
89{
90	enum intparam comparam;
91	int create_failed, stopping;
92
93	if (paralimit == 0) {
94		requeue(j, &runnable);
95		return 1;
96	}
97	create_failed = (j->flags & (JF_STOP | JF_FAILED)) == JF_FAILED;
98	stopping = (j->flags & JF_STOP) != 0;
99	comparam = *j->comparam;
100	for (;;) {
101		if (j->comstring == NULL) {
102			j->comparam += create_failed ? -1 : 1;
103			switch ((comparam = *j->comparam)) {
104			case IP__NULL:
105				return 0;
106			case IP_MOUNT_DEVFS:
107				if (!bool_param(j->intparams[IP_MOUNT_DEVFS]))
108					continue;
109				j->comstring = &dummystring;
110				break;
111			case IP_MOUNT_FDESCFS:
112				if (!bool_param(j->intparams[IP_MOUNT_FDESCFS]))
113					continue;
114				j->comstring = &dummystring;
115				break;
116			case IP_MOUNT_PROCFS:
117				if (!bool_param(j->intparams[IP_MOUNT_PROCFS]))
118					continue;
119				j->comstring = &dummystring;
120				break;
121			case IP__OP:
122			case IP_STOP_TIMEOUT:
123				j->comstring = &dummystring;
124				break;
125			default:
126				if (j->intparams[comparam] == NULL)
127					continue;
128				j->comstring = create_failed || (stopping &&
129				    (j->intparams[comparam]->flags & PF_REV))
130				    ? TAILQ_LAST(&j->intparams[comparam]->val,
131					cfstrings)
132				    : TAILQ_FIRST(&j->intparams[comparam]->val);
133			}
134		} else {
135			j->comstring = j->comstring == &dummystring ? NULL :
136			    create_failed || (stopping &&
137			    (j->intparams[comparam]->flags & PF_REV))
138			    ? TAILQ_PREV(j->comstring, cfstrings, tq)
139			    : TAILQ_NEXT(j->comstring, tq);
140		}
141		if (j->comstring == NULL || j->comstring->len == 0 ||
142		    (create_failed && (comparam == IP_EXEC_PRESTART ||
143		    comparam == IP_EXEC_START || comparam == IP_COMMAND ||
144		    comparam == IP_EXEC_POSTSTART)))
145			continue;
146		switch (run_command(j)) {
147		case -1:
148			failed(j);
149			/* FALLTHROUGH */
150		case 1:
151			return 1;
152		}
153	}
154}
155
156/*
157 * Check command exit status
158 */
159int
160finish_command(struct cfjail *j)
161{
162	int error;
163
164	if (!(j->flags & JF_SLEEPQ))
165		return 0;
166	j->flags &= ~JF_SLEEPQ;
167	if (*j->comparam == IP_STOP_TIMEOUT)
168	{
169		j->flags &= ~JF_TIMEOUT;
170		j->pstatus = 0;
171		return 0;
172	}
173	paralimit++;
174	if (!TAILQ_EMPTY(&runnable))
175		requeue(TAILQ_FIRST(&runnable), &ready);
176	error = 0;
177	if (j->flags & JF_TIMEOUT) {
178		j->flags &= ~JF_TIMEOUT;
179		if (*j->comparam != IP_STOP_TIMEOUT) {
180			jail_warnx(j, "%s: timed out", j->comline);
181			failed(j);
182			error = -1;
183		} else if (verbose > 0)
184			jail_note(j, "timed out\n");
185	} else if (j->pstatus != 0) {
186		if (WIFSIGNALED(j->pstatus))
187			jail_warnx(j, "%s: exited on signal %d",
188			    j->comline, WTERMSIG(j->pstatus));
189		else
190			jail_warnx(j, "%s: failed", j->comline);
191		j->pstatus = 0;
192		failed(j);
193		error = -1;
194	}
195	free(j->comline);
196	j->comline = NULL;
197	return error;
198}
199
200/*
201 * Check for finished processes or timeouts.
202 */
203struct cfjail *
204next_proc(int nonblock)
205{
206	struct kevent ke;
207	struct timespec ts;
208	struct timespec *tsp;
209	struct cfjail *j;
210
211	if (!TAILQ_EMPTY(&sleeping)) {
212	again:
213		tsp = NULL;
214		if ((j = TAILQ_FIRST(&sleeping)) && j->timeout.tv_sec) {
215			clock_gettime(CLOCK_REALTIME, &ts);
216			ts.tv_sec = j->timeout.tv_sec - ts.tv_sec;
217			ts.tv_nsec = j->timeout.tv_nsec - ts.tv_nsec;
218			if (ts.tv_nsec < 0) {
219				ts.tv_sec--;
220				ts.tv_nsec += 1000000000;
221			}
222			if (ts.tv_sec < 0 ||
223			    (ts.tv_sec == 0 && ts.tv_nsec == 0)) {
224				j->flags |= JF_TIMEOUT;
225				clear_procs(j);
226				return j;
227			}
228			tsp = &ts;
229		}
230		if (nonblock) {
231			ts.tv_sec = 0;
232			ts.tv_nsec = 0;
233			tsp = &ts;
234		}
235		switch (kevent(kq, NULL, 0, &ke, 1, tsp)) {
236		case -1:
237			if (errno != EINTR)
238				err(1, "kevent");
239			goto again;
240		case 0:
241			if (!nonblock) {
242				j = TAILQ_FIRST(&sleeping);
243				j->flags |= JF_TIMEOUT;
244				clear_procs(j);
245				return j;
246			}
247			break;
248		case 1:
249			(void)waitpid(ke.ident, NULL, WNOHANG);
250			if ((j = find_proc(ke.ident))) {
251				j->pstatus = ke.data;
252				return j;
253			}
254			goto again;
255		}
256	}
257	return NULL;
258}
259
260/*
261 * Run a single command for a jail, possible inside the jail.
262 */
263static int
264run_command(struct cfjail *j)
265{
266	const struct passwd *pwd;
267	const struct cfstring *comstring, *s;
268	login_cap_t *lcap;
269	char **argv;
270	char *cs, *comcs, *devpath;
271	const char *jidstr, *conslog, *path, *ruleset, *term, *username;
272	enum intparam comparam;
273	size_t comlen;
274	pid_t pid;
275	int argc, bg, clean, consfd, down, fib, i, injail, sjuser, timeout;
276#if defined(INET) || defined(INET6)
277	char *addr, *extrap, *p, *val;
278#endif
279
280	static char *cleanenv;
281
282	/* Perform some operations that aren't actually commands */
283	comparam = *j->comparam;
284	down = j->flags & (JF_STOP | JF_FAILED);
285	switch (comparam) {
286	case IP_STOP_TIMEOUT:
287		return term_procs(j);
288
289	case IP__OP:
290		if (down) {
291			if (jail_remove(j->jid) < 0 && errno == EPERM) {
292				jail_warnx(j, "jail_remove: %s",
293					   strerror(errno));
294				return -1;
295			}
296			if (verbose > 0 || (verbose == 0 && (j->flags & JF_STOP
297			    ? note_remove : j->name != NULL)))
298			    jail_note(j, "removed\n");
299			j->jid = -1;
300			if (j->flags & JF_STOP)
301				dep_done(j, DF_LIGHT);
302			else
303				j->flags &= ~JF_PERSIST;
304		} else {
305			if (create_jail(j) < 0)
306				return -1;
307			if (iflag)
308				printf("%d\n", j->jid);
309			if (verbose >= 0 && (j->name || verbose > 0))
310				jail_note(j, "created\n");
311			dep_done(j, DF_LIGHT);
312		}
313		return 0;
314
315	default: ;
316	}
317	/*
318	 * Collect exec arguments.  Internal commands for network and
319	 * mounting build their own argument lists.
320	 */
321	comstring = j->comstring;
322	bg = 0;
323	switch (comparam) {
324#ifdef INET
325	case IP__IP4_IFADDR:
326		argc = 0;
327		val = alloca(strlen(comstring->s) + 1);
328		strcpy(val, comstring->s);
329		cs = val;
330		extrap = NULL;
331		while ((p = strchr(cs, ' ')) != NULL && strlen(p) > 1) {
332			if (extrap == NULL) {
333				*p = '\0';
334				extrap = p + 1;
335			}
336			cs = p + 1;
337			argc++;
338		}
339
340		argv = alloca((8 + argc) * sizeof(char *));
341		*(const char **)&argv[0] = _PATH_IFCONFIG;
342		if ((cs = strchr(val, '|'))) {
343			argv[1] = alloca(cs - val + 1);
344			strlcpy(argv[1], val, cs - val + 1);
345			addr = cs + 1;
346		} else {
347			*(const char **)&argv[1] =
348			    string_param(j->intparams[IP_INTERFACE]);
349			addr = val;
350		}
351		*(const char **)&argv[2] = "inet";
352		if (!(cs = strchr(addr, '/'))) {
353			argv[3] = addr;
354			*(const char **)&argv[4] = "netmask";
355			*(const char **)&argv[5] = "255.255.255.255";
356			argc = 6;
357		} else if (strchr(cs + 1, '.')) {
358			argv[3] = alloca(cs - addr + 1);
359			strlcpy(argv[3], addr, cs - addr + 1);
360			*(const char **)&argv[4] = "netmask";
361			*(const char **)&argv[5] = cs + 1;
362			argc = 6;
363		} else {
364			argv[3] = addr;
365			argc = 4;
366		}
367
368		if (!down) {
369			for (cs = strtok(extrap, " "); cs; cs = strtok(NULL, " ")) {
370				size_t len = strlen(cs) + 1;
371				argv[argc] = alloca(len);
372				strlcpy(argv[argc++], cs, len);
373			}
374		}
375
376		*(const char **)&argv[argc] = down ? "-alias" : "alias";
377		argv[argc + 1] = NULL;
378		break;
379#endif
380
381#ifdef INET6
382	case IP__IP6_IFADDR:
383		argc = 0;
384		val = alloca(strlen(comstring->s) + 1);
385		strcpy(val, comstring->s);
386		cs = val;
387		extrap = NULL;
388		while ((p = strchr(cs, ' ')) != NULL && strlen(p) > 1) {
389			if (extrap == NULL) {
390				*p = '\0';
391				extrap = p + 1;
392			}
393			cs = p + 1;
394			argc++;
395		}
396
397		argv = alloca((8 + argc) * sizeof(char *));
398		*(const char **)&argv[0] = _PATH_IFCONFIG;
399		if ((cs = strchr(val, '|'))) {
400			argv[1] = alloca(cs - val + 1);
401			strlcpy(argv[1], val, cs - val + 1);
402			addr = cs + 1;
403		} else {
404			*(const char **)&argv[1] =
405			    string_param(j->intparams[IP_INTERFACE]);
406			addr = val;
407		}
408		*(const char **)&argv[2] = "inet6";
409		argv[3] = addr;
410		if (!(cs = strchr(addr, '/'))) {
411			*(const char **)&argv[4] = "prefixlen";
412			*(const char **)&argv[5] = "128";
413			argc = 6;
414		} else
415			argc = 4;
416
417		if (!down) {
418			for (cs = strtok(extrap, " "); cs; cs = strtok(NULL, " ")) {
419				size_t len = strlen(cs) + 1;
420				argv[argc] = alloca(len);
421				strlcpy(argv[argc++], cs, len);
422			}
423		}
424
425		*(const char **)&argv[argc] = down ? "-alias" : "alias";
426		argv[argc + 1] = NULL;
427		break;
428#endif
429
430	case IP_VNET_INTERFACE:
431		argv = alloca(5 * sizeof(char *));
432		*(const char **)&argv[0] = _PATH_IFCONFIG;
433		argv[1] = comstring->s;
434		*(const char **)&argv[2] = down ? "-vnet" : "vnet";
435		jidstr = string_param(j->intparams[KP_JID]);
436		*(const char **)&argv[3] =
437			jidstr ? jidstr : string_param(j->intparams[KP_NAME]);
438		argv[4] = NULL;
439		break;
440
441	case IP_MOUNT:
442	case IP__MOUNT_FROM_FSTAB:
443		argv = alloca(8 * sizeof(char *));
444		comcs = alloca(comstring->len + 1);
445		strcpy(comcs, comstring->s);
446		argc = 0;
447		for (cs = strtok(comcs, " \t\f\v\r\n"); cs && argc < 4;
448		     cs = strtok(NULL, " \t\f\v\r\n"))
449			argv[argc++] = cs;
450		if (argc == 0)
451			return 0;
452		if (argc < 3) {
453			jail_warnx(j, "%s: %s: missing information",
454			    j->intparams[comparam]->name, comstring->s);
455			return -1;
456		}
457		if (check_path(j, j->intparams[comparam]->name, argv[1], 0,
458		    down ? argv[2] : NULL) < 0)
459			return -1;
460		if (down) {
461			argv[4] = NULL;
462			argv[3] = argv[1];
463			*(const char **)&argv[0] = "/sbin/umount";
464		} else {
465			if (argc == 4) {
466				argv[7] = NULL;
467				argv[6] = argv[1];
468				argv[5] = argv[0];
469				argv[4] = argv[3];
470				*(const char **)&argv[3] = "-o";
471			} else {
472				argv[5] = NULL;
473				argv[4] = argv[1];
474				argv[3] = argv[0];
475			}
476			*(const char **)&argv[0] = _PATH_MOUNT;
477		}
478		*(const char **)&argv[1] = "-t";
479		break;
480
481	case IP_MOUNT_DEVFS:
482		argv = alloca(7 * sizeof(char *));
483		path = string_param(j->intparams[KP_PATH]);
484		if (path == NULL) {
485			jail_warnx(j, "mount.devfs: no path");
486			return -1;
487		}
488		devpath = alloca(strlen(path) + 5);
489		sprintf(devpath, "%s/dev", path);
490		if (check_path(j, "mount.devfs", devpath, 0,
491		    down ? "devfs" : NULL) < 0)
492			return -1;
493		if (down) {
494			*(const char **)&argv[0] = "/sbin/umount";
495			argv[1] = devpath;
496			argv[2] = NULL;
497		} else {
498			*(const char **)&argv[0] = _PATH_MOUNT;
499			*(const char **)&argv[1] = "-t";
500			*(const char **)&argv[2] = "devfs";
501			ruleset = string_param(j->intparams[KP_DEVFS_RULESET]);
502			if (!ruleset)
503			    ruleset = "4";	/* devfsrules_jail */
504			argv[3] = alloca(11 + strlen(ruleset));
505			sprintf(argv[3], "-oruleset=%s", ruleset);
506			*(const char **)&argv[4] = ".";
507			argv[5] = devpath;
508			argv[6] = NULL;
509		}
510		break;
511
512	case IP_MOUNT_FDESCFS:
513		argv = alloca(7 * sizeof(char *));
514		path = string_param(j->intparams[KP_PATH]);
515		if (path == NULL) {
516			jail_warnx(j, "mount.fdescfs: no path");
517			return -1;
518		}
519		devpath = alloca(strlen(path) + 8);
520		sprintf(devpath, "%s/dev/fd", path);
521		if (check_path(j, "mount.fdescfs", devpath, 0,
522		    down ? "fdescfs" : NULL) < 0)
523			return -1;
524		if (down) {
525			*(const char **)&argv[0] = "/sbin/umount";
526			argv[1] = devpath;
527			argv[2] = NULL;
528		} else {
529			*(const char **)&argv[0] = _PATH_MOUNT;
530			*(const char **)&argv[1] = "-t";
531			*(const char **)&argv[2] = "fdescfs";
532			*(const char **)&argv[3] = ".";
533			argv[4] = devpath;
534			argv[5] = NULL;
535		}
536		break;
537
538	case IP_MOUNT_PROCFS:
539		argv = alloca(7 * sizeof(char *));
540		path = string_param(j->intparams[KP_PATH]);
541		if (path == NULL) {
542			jail_warnx(j, "mount.procfs: no path");
543			return -1;
544		}
545		devpath = alloca(strlen(path) + 6);
546		sprintf(devpath, "%s/proc", path);
547		if (check_path(j, "mount.procfs", devpath, 0,
548		    down ? "procfs" : NULL) < 0)
549			return -1;
550		if (down) {
551			*(const char **)&argv[0] = "/sbin/umount";
552			argv[1] = devpath;
553			argv[2] = NULL;
554		} else {
555			*(const char **)&argv[0] = _PATH_MOUNT;
556			*(const char **)&argv[1] = "-t";
557			*(const char **)&argv[2] = "procfs";
558			*(const char **)&argv[3] = ".";
559			argv[4] = devpath;
560			argv[5] = NULL;
561		}
562		break;
563
564	case IP_COMMAND:
565		if (j->name != NULL)
566			goto default_command;
567		argc = 0;
568		TAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq)
569			argc++;
570		argv = alloca((argc + 1) * sizeof(char *));
571		argc = 0;
572		TAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq)
573			argv[argc++] = s->s;
574		argv[argc] = NULL;
575		j->comstring = &dummystring;
576		break;
577
578	default:
579	default_command:
580		if ((cs = strpbrk(comstring->s, "!\"$&'()*;<>?[\\]`{|}~")) &&
581		    !(cs[0] == '&' && cs[1] == '\0')) {
582			argv = alloca(4 * sizeof(char *));
583			*(const char **)&argv[0] = _PATH_BSHELL;
584			*(const char **)&argv[1] = "-c";
585			argv[2] = comstring->s;
586			argv[3] = NULL;
587		} else {
588			if (cs) {
589				*cs = 0;
590				bg = 1;
591			}
592			comcs = alloca(comstring->len + 1);
593			strcpy(comcs, comstring->s);
594			argc = 0;
595			for (cs = strtok(comcs, " \t\f\v\r\n"); cs;
596			     cs = strtok(NULL, " \t\f\v\r\n"))
597				argc++;
598			argv = alloca((argc + 1) * sizeof(char *));
599			strcpy(comcs, comstring->s);
600			argc = 0;
601			for (cs = strtok(comcs, " \t\f\v\r\n"); cs;
602			     cs = strtok(NULL, " \t\f\v\r\n"))
603				argv[argc++] = cs;
604			argv[argc] = NULL;
605		}
606	}
607	if (argv[0] == NULL)
608		return 0;
609
610	if (int_param(j->intparams[IP_EXEC_TIMEOUT], &timeout) &&
611	    timeout != 0) {
612		clock_gettime(CLOCK_REALTIME, &j->timeout);
613		j->timeout.tv_sec += timeout;
614	} else
615		j->timeout.tv_sec = 0;
616
617	injail = comparam == IP_EXEC_START || comparam == IP_COMMAND ||
618	    comparam == IP_EXEC_STOP;
619	clean = bool_param(j->intparams[IP_EXEC_CLEAN]);
620	username = string_param(j->intparams[injail
621	    ? IP_EXEC_JAIL_USER : IP_EXEC_SYSTEM_USER]);
622	sjuser = bool_param(j->intparams[IP_EXEC_SYSTEM_JAIL_USER]);
623
624	consfd = 0;
625	if (injail &&
626	    (conslog = string_param(j->intparams[IP_EXEC_CONSOLELOG]))) {
627		if (check_path(j, "exec.consolelog", conslog, 1, NULL) < 0)
628			return -1;
629		consfd =
630		    open(conslog, O_WRONLY | O_CREAT | O_APPEND, DEFFILEMODE);
631		if (consfd < 0) {
632			jail_warnx(j, "open %s: %s", conslog, strerror(errno));
633			return -1;
634		}
635	}
636
637	comlen = 0;
638	for (i = 0; argv[i]; i++)
639		comlen += strlen(argv[i]) + 1;
640	j->comline = cs = emalloc(comlen);
641	for (i = 0; argv[i]; i++) {
642		strcpy(cs, argv[i]);
643		if (argv[i + 1]) {
644			cs += strlen(argv[i]) + 1;
645			cs[-1] = ' ';
646		}
647	}
648	if (verbose > 0)
649		jail_note(j, "run command%s%s%s: %s\n",
650		    injail ? " in jail" : "", username ? " as " : "",
651		    username ? username : "", j->comline);
652
653	pid = fork();
654	if (pid < 0)
655		err(1, "fork");
656	if (pid > 0) {
657		if (bg || !add_proc(j, pid)) {
658			free(j->comline);
659			j->comline = NULL;
660			return 0;
661		} else {
662			paralimit--;
663			return 1;
664		}
665	}
666	if (bg)
667		setsid();
668
669	/* Set up the environment and run the command */
670	pwd = NULL;
671	lcap = NULL;
672	if ((clean || username) && injail && sjuser &&
673	    get_user_info(j, username, &pwd, &lcap) < 0)
674		exit(1);
675	if (injail) {
676		/* jail_attach won't chdir along with its chroot. */
677		path = string_param(j->intparams[KP_PATH]);
678		if (path && chdir(path) < 0) {
679			jail_warnx(j, "chdir %s: %s", path, strerror(errno));
680			exit(1);
681		}
682		if (int_param(j->intparams[IP_EXEC_FIB], &fib) &&
683		    setfib(fib) < 0) {
684			jail_warnx(j, "setfib: %s", strerror(errno));
685			exit(1);
686		}
687		if (jail_attach(j->jid) < 0) {
688			jail_warnx(j, "jail_attach: %s", strerror(errno));
689			exit(1);
690		}
691	}
692	if (clean || username) {
693		if (!(injail && sjuser) &&
694		    get_user_info(j, username, &pwd, &lcap) < 0)
695			exit(1);
696		if (clean) {
697			term = getenv("TERM");
698			environ = &cleanenv;
699			setenv("PATH", "/bin:/usr/bin", 0);
700			if (term != NULL)
701				setenv("TERM", term, 1);
702		}
703		if (setgid(pwd->pw_gid) < 0) {
704			jail_warnx(j, "setgid %d: %s", pwd->pw_gid,
705			    strerror(errno));
706			exit(1);
707		}
708		if (setusercontext(lcap, pwd, pwd->pw_uid, username
709		    ? LOGIN_SETALL & ~LOGIN_SETGROUP & ~LOGIN_SETLOGIN
710		    : LOGIN_SETPATH | LOGIN_SETENV) < 0) {
711			jail_warnx(j, "setusercontext %s: %s", pwd->pw_name,
712			    strerror(errno));
713			exit(1);
714		}
715		login_close(lcap);
716		setenv("USER", pwd->pw_name, 1);
717		setenv("HOME", pwd->pw_dir, 1);
718		setenv("SHELL",
719		    *pwd->pw_shell ? pwd->pw_shell : _PATH_BSHELL, 1);
720		if (clean && chdir(pwd->pw_dir) < 0) {
721			jail_warnx(j, "chdir %s: %s",
722			    pwd->pw_dir, strerror(errno));
723			exit(1);
724		}
725		endpwent();
726	}
727
728	if (consfd != 0 && (dup2(consfd, 1) < 0 || dup2(consfd, 2) < 0)) {
729		jail_warnx(j, "exec.consolelog: %s", strerror(errno));
730		exit(1);
731	}
732	closefrom(3);
733	execvp(argv[0], argv);
734	jail_warnx(j, "exec %s: %s", argv[0], strerror(errno));
735	exit(1);
736}
737
738/*
739 * Add a process to the hash, tied to a jail.
740 */
741static int
742add_proc(struct cfjail *j, pid_t pid)
743{
744	struct kevent ke;
745	struct cfjail *tj;
746	struct phash *ph;
747
748	if (!kq && (kq = kqueue()) < 0)
749		err(1, "kqueue");
750	EV_SET(&ke, pid, EVFILT_PROC, EV_ADD, NOTE_EXIT, 0, NULL);
751	if (kevent(kq, &ke, 1, NULL, 0, NULL) < 0) {
752		if (errno == ESRCH)
753			return 0;
754		err(1, "kevent");
755	}
756	ph = emalloc(sizeof(struct phash));
757	ph->j = j;
758	ph->pid = pid;
759	LIST_INSERT_HEAD(&phash[pid % PHASH_SIZE], ph, le);
760	j->nprocs++;
761	j->flags |= JF_SLEEPQ;
762	if (j->timeout.tv_sec == 0)
763		requeue(j, &sleeping);
764	else {
765		/* File the jail in the sleep queue according to its timeout. */
766		TAILQ_REMOVE(j->queue, j, tq);
767		TAILQ_FOREACH(tj, &sleeping, tq) {
768			if (!tj->timeout.tv_sec ||
769			    j->timeout.tv_sec < tj->timeout.tv_sec ||
770			    (j->timeout.tv_sec == tj->timeout.tv_sec &&
771			    j->timeout.tv_nsec <= tj->timeout.tv_nsec)) {
772				TAILQ_INSERT_BEFORE(tj, j, tq);
773				break;
774			}
775		}
776		if (tj == NULL)
777			TAILQ_INSERT_TAIL(&sleeping, j, tq);
778		j->queue = &sleeping;
779	}
780	return 1;
781}
782
783/*
784 * Remove any processes from the hash that correspond to a jail.
785 */
786static void
787clear_procs(struct cfjail *j)
788{
789	struct kevent ke;
790	struct phash *ph, *tph;
791	int i;
792
793	j->nprocs = 0;
794	for (i = 0; i < PHASH_SIZE; i++)
795		LIST_FOREACH_SAFE(ph, &phash[i], le, tph)
796			if (ph->j == j) {
797				EV_SET(&ke, ph->pid, EVFILT_PROC, EV_DELETE,
798				    NOTE_EXIT, 0, NULL);
799				(void)kevent(kq, &ke, 1, NULL, 0, NULL);
800				LIST_REMOVE(ph, le);
801				free(ph);
802			}
803}
804
805/*
806 * Find the jail that corresponds to an exited process.
807 */
808static struct cfjail *
809find_proc(pid_t pid)
810{
811	struct cfjail *j;
812	struct phash *ph;
813
814	LIST_FOREACH(ph, &phash[pid % PHASH_SIZE], le)
815		if (ph->pid == pid) {
816			j = ph->j;
817			LIST_REMOVE(ph, le);
818			free(ph);
819			return --j->nprocs ? NULL : j;
820		}
821	return NULL;
822}
823
824/*
825 * Send SIGTERM to all processes in a jail and wait for them to die.
826 */
827static int
828term_procs(struct cfjail *j)
829{
830	struct kinfo_proc *ki;
831	int i, noted, pcnt, timeout;
832
833	static kvm_t *kd;
834
835	if (!int_param(j->intparams[IP_STOP_TIMEOUT], &timeout))
836		timeout = DEFAULT_STOP_TIMEOUT;
837	else if (timeout == 0)
838		return 0;
839
840	if (kd == NULL) {
841		kd = kvm_open(NULL, NULL, NULL, O_RDONLY, NULL);
842		if (kd == NULL)
843			return 0;
844	}
845
846	ki = kvm_getprocs(kd, KERN_PROC_PROC, 0, &pcnt);
847	if (ki == NULL)
848		return 0;
849	noted = 0;
850	for (i = 0; i < pcnt; i++)
851		if (ki[i].ki_jid == j->jid &&
852		    kill(ki[i].ki_pid, SIGTERM) == 0) {
853			(void)add_proc(j, ki[i].ki_pid);
854			if (verbose > 0) {
855				if (!noted) {
856					noted = 1;
857					jail_note(j, "sent SIGTERM to:");
858				}
859				printf(" %d", ki[i].ki_pid);
860			}
861		}
862	if (noted)
863		printf("\n");
864	if (j->nprocs > 0) {
865		clock_gettime(CLOCK_REALTIME, &j->timeout);
866		j->timeout.tv_sec += timeout;
867		return 1;
868	}
869	return 0;
870}
871
872/*
873 * Look up a user in the passwd and login.conf files.
874 */
875static int
876get_user_info(struct cfjail *j, const char *username,
877    const struct passwd **pwdp, login_cap_t **lcapp)
878{
879	const struct passwd *pwd;
880
881	*pwdp = pwd = username ? getpwnam(username) : getpwuid(getuid());
882	if (pwd == NULL) {
883		if (errno)
884			jail_warnx(j, "getpwnam%s%s: %s", username ? " " : "",
885			    username ? username : "", strerror(errno));
886		else if (username)
887			jail_warnx(j, "%s: no such user", username);
888		else
889			jail_warnx(j, "unknown uid %d", getuid());
890		return -1;
891	}
892	*lcapp = login_getpwclass(pwd);
893	if (*lcapp == NULL) {
894		jail_warnx(j, "getpwclass %s: %s", pwd->pw_name,
895		    strerror(errno));
896		return -1;
897	}
898	/* Set the groups while the group file is still available */
899	if (initgroups(pwd->pw_name, pwd->pw_gid) < 0) {
900		jail_warnx(j, "initgroups %s: %s", pwd->pw_name,
901		    strerror(errno));
902		return -1;
903	}
904	return 0;
905}
906
907/*
908 * Make sure a mount or consolelog path is a valid absolute pathname
909 * with no symlinks.
910 */
911static int
912check_path(struct cfjail *j, const char *pname, const char *path, int isfile,
913    const char *umount_type)
914{
915	struct stat st, mpst;
916	struct statfs stfs;
917	char *tpath, *p;
918	const char *jailpath;
919	size_t jplen;
920
921	if (path[0] != '/') {
922		jail_warnx(j, "%s: %s: not an absolute pathname",
923		    pname, path);
924		return -1;
925	}
926	/*
927	 * Only check for symlinks in components below the jail's path,
928	 * since that's where the security risk lies.
929	 */
930	jailpath = string_param(j->intparams[KP_PATH]);
931	if (jailpath == NULL)
932		jailpath = "";
933	jplen = strlen(jailpath);
934	if (!strncmp(path, jailpath, jplen) && path[jplen] == '/') {
935		tpath = alloca(strlen(path) + 1);
936		strcpy(tpath, path);
937		for (p = tpath + jplen; p != NULL; ) {
938			p = strchr(p + 1, '/');
939			if (p)
940				*p = '\0';
941			if (lstat(tpath, &st) < 0) {
942				if (errno == ENOENT && isfile && !p)
943					break;
944				jail_warnx(j, "%s: %s: %s", pname, tpath,
945				    strerror(errno));
946				return -1;
947			}
948			if (S_ISLNK(st.st_mode)) {
949				jail_warnx(j, "%s: %s is a symbolic link",
950				    pname, tpath);
951				return -1;
952			}
953			if (p)
954				*p = '/';
955		}
956	}
957	if (umount_type != NULL) {
958		if (stat(path, &st) < 0 || statfs(path, &stfs) < 0) {
959			jail_warnx(j, "%s: %s: %s", pname, path,
960			    strerror(errno));
961			return -1;
962		}
963		if (stat(stfs.f_mntonname, &mpst) < 0) {
964			jail_warnx(j, "%s: %s: %s", pname, stfs.f_mntonname,
965			    strerror(errno));
966			return -1;
967		}
968		if (st.st_ino != mpst.st_ino) {
969			jail_warnx(j, "%s: %s: not a mount point",
970			    pname, path);
971			return -1;
972		}
973		if (strcmp(stfs.f_fstypename, umount_type)) {
974			jail_warnx(j, "%s: %s: not a %s mount",
975			    pname, path, umount_type);
976			return -1;
977		}
978	}
979	return 0;
980}
981