xref: /freebsd/sys/kern/kern_jail.c (revision 2f513db72b034fd5ef7f080b11be5c711c15186a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1999 Poul-Henning Kamp.
5  * Copyright (c) 2008 Bjoern A. Zeeb.
6  * Copyright (c) 2009 James Gritton.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include "opt_ddb.h"
35 #include "opt_inet.h"
36 #include "opt_inet6.h"
37 
38 #include <sys/param.h>
39 #include <sys/types.h>
40 #include <sys/kernel.h>
41 #include <sys/systm.h>
42 #include <sys/errno.h>
43 #include <sys/sysproto.h>
44 #include <sys/malloc.h>
45 #include <sys/osd.h>
46 #include <sys/priv.h>
47 #include <sys/proc.h>
48 #include <sys/taskqueue.h>
49 #include <sys/fcntl.h>
50 #include <sys/jail.h>
51 #include <sys/lock.h>
52 #include <sys/mutex.h>
53 #include <sys/racct.h>
54 #include <sys/rctl.h>
55 #include <sys/refcount.h>
56 #include <sys/sx.h>
57 #include <sys/sysent.h>
58 #include <sys/namei.h>
59 #include <sys/mount.h>
60 #include <sys/queue.h>
61 #include <sys/socket.h>
62 #include <sys/syscallsubr.h>
63 #include <sys/sysctl.h>
64 #include <sys/vnode.h>
65 
66 #include <net/if.h>
67 #include <net/vnet.h>
68 
69 #include <netinet/in.h>
70 
71 #ifdef DDB
72 #include <ddb/ddb.h>
73 #endif /* DDB */
74 
75 #include <security/mac/mac_framework.h>
76 
77 #define	DEFAULT_HOSTUUID	"00000000-0000-0000-0000-000000000000"
78 
79 MALLOC_DEFINE(M_PRISON, "prison", "Prison structures");
80 static MALLOC_DEFINE(M_PRISON_RACCT, "prison_racct", "Prison racct structures");
81 
82 /* Keep struct prison prison0 and some code in kern_jail_set() readable. */
83 #ifdef INET
84 #ifdef INET6
85 #define	_PR_IP_SADDRSEL	PR_IP4_SADDRSEL|PR_IP6_SADDRSEL
86 #else
87 #define	_PR_IP_SADDRSEL	PR_IP4_SADDRSEL
88 #endif
89 #else /* !INET */
90 #ifdef INET6
91 #define	_PR_IP_SADDRSEL	PR_IP6_SADDRSEL
92 #else
93 #define	_PR_IP_SADDRSEL	0
94 #endif
95 #endif
96 
97 /* prison0 describes what is "real" about the system. */
98 struct prison prison0 = {
99 	.pr_id		= 0,
100 	.pr_name	= "0",
101 	.pr_ref		= 1,
102 	.pr_uref	= 1,
103 	.pr_path	= "/",
104 	.pr_securelevel	= -1,
105 	.pr_devfs_rsnum = 0,
106 	.pr_childmax	= JAIL_MAX,
107 	.pr_hostuuid	= DEFAULT_HOSTUUID,
108 	.pr_children	= LIST_HEAD_INITIALIZER(prison0.pr_children),
109 #ifdef VIMAGE
110 	.pr_flags	= PR_HOST|PR_VNET|_PR_IP_SADDRSEL,
111 #else
112 	.pr_flags	= PR_HOST|_PR_IP_SADDRSEL,
113 #endif
114 	.pr_allow	= PR_ALLOW_ALL_STATIC,
115 };
116 MTX_SYSINIT(prison0, &prison0.pr_mtx, "jail mutex", MTX_DEF);
117 
118 struct bool_flags {
119 	const char	*name;
120 	const char	*noname;
121 	unsigned	 flag;
122 };
123 struct jailsys_flags {
124 	const char	*name;
125 	unsigned	 disable;
126 	unsigned	 new;
127 };
128 
129 /* allprison, allprison_racct and lastprid are protected by allprison_lock. */
130 struct	sx allprison_lock;
131 SX_SYSINIT(allprison_lock, &allprison_lock, "allprison");
132 struct	prisonlist allprison = TAILQ_HEAD_INITIALIZER(allprison);
133 LIST_HEAD(, prison_racct) allprison_racct;
134 int	lastprid = 0;
135 
136 static int do_jail_attach(struct thread *td, struct prison *pr);
137 static void prison_complete(void *context, int pending);
138 static void prison_deref(struct prison *pr, int flags);
139 static char *prison_path(struct prison *pr1, struct prison *pr2);
140 static void prison_remove_one(struct prison *pr);
141 #ifdef RACCT
142 static void prison_racct_attach(struct prison *pr);
143 static void prison_racct_modify(struct prison *pr);
144 static void prison_racct_detach(struct prison *pr);
145 #endif
146 
147 /* Flags for prison_deref */
148 #define	PD_DEREF	0x01
149 #define	PD_DEUREF	0x02
150 #define	PD_LOCKED	0x04
151 #define	PD_LIST_SLOCKED	0x08
152 #define	PD_LIST_XLOCKED	0x10
153 
154 /*
155  * Parameter names corresponding to PR_* flag values.  Size values are for kvm
156  * as we cannot figure out the size of a sparse array, or an array without a
157  * terminating entry.
158  */
159 static struct bool_flags pr_flag_bool[] = {
160 	{"persist", "nopersist", PR_PERSIST},
161 #ifdef INET
162 	{"ip4.saddrsel", "ip4.nosaddrsel", PR_IP4_SADDRSEL},
163 #endif
164 #ifdef INET6
165 	{"ip6.saddrsel", "ip6.nosaddrsel", PR_IP6_SADDRSEL},
166 #endif
167 };
168 const size_t pr_flag_bool_size = sizeof(pr_flag_bool);
169 
170 static struct jailsys_flags pr_flag_jailsys[] = {
171 	{"host", 0, PR_HOST},
172 #ifdef VIMAGE
173 	{"vnet", 0, PR_VNET},
174 #endif
175 #ifdef INET
176 	{"ip4", PR_IP4_USER, PR_IP4_USER},
177 #endif
178 #ifdef INET6
179 	{"ip6", PR_IP6_USER, PR_IP6_USER},
180 #endif
181 };
182 const size_t pr_flag_jailsys_size = sizeof(pr_flag_jailsys);
183 
184 /* Make this array full-size so dynamic parameters can be added. */
185 static struct bool_flags pr_flag_allow[NBBY * NBPW] = {
186 	{"allow.set_hostname", "allow.noset_hostname", PR_ALLOW_SET_HOSTNAME},
187 	{"allow.sysvipc", "allow.nosysvipc", PR_ALLOW_SYSVIPC},
188 	{"allow.raw_sockets", "allow.noraw_sockets", PR_ALLOW_RAW_SOCKETS},
189 	{"allow.chflags", "allow.nochflags", PR_ALLOW_CHFLAGS},
190 	{"allow.mount", "allow.nomount", PR_ALLOW_MOUNT},
191 	{"allow.quotas", "allow.noquotas", PR_ALLOW_QUOTAS},
192 	{"allow.socket_af", "allow.nosocket_af", PR_ALLOW_SOCKET_AF},
193 	{"allow.mlock", "allow.nomlock", PR_ALLOW_MLOCK},
194 	{"allow.reserved_ports", "allow.noreserved_ports",
195 	 PR_ALLOW_RESERVED_PORTS},
196 	{"allow.read_msgbuf", "allow.noread_msgbuf", PR_ALLOW_READ_MSGBUF},
197 	{"allow.unprivileged_proc_debug", "allow.nounprivileged_proc_debug",
198 	 PR_ALLOW_UNPRIV_DEBUG},
199 };
200 const size_t pr_flag_allow_size = sizeof(pr_flag_allow);
201 
202 #define	JAIL_DEFAULT_ALLOW		(PR_ALLOW_SET_HOSTNAME | \
203 					 PR_ALLOW_RESERVED_PORTS | \
204 					 PR_ALLOW_UNPRIV_DEBUG)
205 #define	JAIL_DEFAULT_ENFORCE_STATFS	2
206 #define	JAIL_DEFAULT_DEVFS_RSNUM	0
207 static unsigned jail_default_allow = JAIL_DEFAULT_ALLOW;
208 static int jail_default_enforce_statfs = JAIL_DEFAULT_ENFORCE_STATFS;
209 static int jail_default_devfs_rsnum = JAIL_DEFAULT_DEVFS_RSNUM;
210 #if defined(INET) || defined(INET6)
211 static unsigned jail_max_af_ips = 255;
212 #endif
213 
214 /*
215  * Initialize the parts of prison0 that can't be static-initialized with
216  * constants.  This is called from proc0_init() after creating thread0 cpuset.
217  */
218 void
219 prison0_init(void)
220 {
221 
222 	prison0.pr_cpuset = cpuset_ref(thread0.td_cpuset);
223 	prison0.pr_osreldate = osreldate;
224 	strlcpy(prison0.pr_osrelease, osrelease, sizeof(prison0.pr_osrelease));
225 }
226 
227 /*
228  * struct jail_args {
229  *	struct jail *jail;
230  * };
231  */
232 int
233 sys_jail(struct thread *td, struct jail_args *uap)
234 {
235 	uint32_t version;
236 	int error;
237 	struct jail j;
238 
239 	error = copyin(uap->jail, &version, sizeof(uint32_t));
240 	if (error)
241 		return (error);
242 
243 	switch (version) {
244 	case 0:
245 	{
246 		struct jail_v0 j0;
247 
248 		/* FreeBSD single IPv4 jails. */
249 		bzero(&j, sizeof(struct jail));
250 		error = copyin(uap->jail, &j0, sizeof(struct jail_v0));
251 		if (error)
252 			return (error);
253 		j.version = j0.version;
254 		j.path = j0.path;
255 		j.hostname = j0.hostname;
256 		j.ip4s = htonl(j0.ip_number);	/* jail_v0 is host order */
257 		break;
258 	}
259 
260 	case 1:
261 		/*
262 		 * Version 1 was used by multi-IPv4 jail implementations
263 		 * that never made it into the official kernel.
264 		 */
265 		return (EINVAL);
266 
267 	case 2:	/* JAIL_API_VERSION */
268 		/* FreeBSD multi-IPv4/IPv6,noIP jails. */
269 		error = copyin(uap->jail, &j, sizeof(struct jail));
270 		if (error)
271 			return (error);
272 		break;
273 
274 	default:
275 		/* Sci-Fi jails are not supported, sorry. */
276 		return (EINVAL);
277 	}
278 	return (kern_jail(td, &j));
279 }
280 
281 int
282 kern_jail(struct thread *td, struct jail *j)
283 {
284 	struct iovec optiov[2 * (4 + nitems(pr_flag_allow)
285 #ifdef INET
286 			    + 1
287 #endif
288 #ifdef INET6
289 			    + 1
290 #endif
291 			    )];
292 	struct uio opt;
293 	char *u_path, *u_hostname, *u_name;
294 	struct bool_flags *bf;
295 #ifdef INET
296 	uint32_t ip4s;
297 	struct in_addr *u_ip4;
298 #endif
299 #ifdef INET6
300 	struct in6_addr *u_ip6;
301 #endif
302 	size_t tmplen;
303 	int error, enforce_statfs;
304 
305 	bzero(&optiov, sizeof(optiov));
306 	opt.uio_iov = optiov;
307 	opt.uio_iovcnt = 0;
308 	opt.uio_offset = -1;
309 	opt.uio_resid = -1;
310 	opt.uio_segflg = UIO_SYSSPACE;
311 	opt.uio_rw = UIO_READ;
312 	opt.uio_td = td;
313 
314 	/* Set permissions for top-level jails from sysctls. */
315 	if (!jailed(td->td_ucred)) {
316 		for (bf = pr_flag_allow;
317 		     bf < pr_flag_allow + nitems(pr_flag_allow) &&
318 			bf->flag != 0;
319 		     bf++) {
320 			optiov[opt.uio_iovcnt].iov_base = __DECONST(char *,
321 			    (jail_default_allow & bf->flag)
322 			    ? bf->name : bf->noname);
323 			optiov[opt.uio_iovcnt].iov_len =
324 			    strlen(optiov[opt.uio_iovcnt].iov_base) + 1;
325 			opt.uio_iovcnt += 2;
326 		}
327 		optiov[opt.uio_iovcnt].iov_base = "enforce_statfs";
328 		optiov[opt.uio_iovcnt].iov_len = sizeof("enforce_statfs");
329 		opt.uio_iovcnt++;
330 		enforce_statfs = jail_default_enforce_statfs;
331 		optiov[opt.uio_iovcnt].iov_base = &enforce_statfs;
332 		optiov[opt.uio_iovcnt].iov_len = sizeof(enforce_statfs);
333 		opt.uio_iovcnt++;
334 	}
335 
336 	tmplen = MAXPATHLEN + MAXHOSTNAMELEN + MAXHOSTNAMELEN;
337 #ifdef INET
338 	ip4s = (j->version == 0) ? 1 : j->ip4s;
339 	if (ip4s > jail_max_af_ips)
340 		return (EINVAL);
341 	tmplen += ip4s * sizeof(struct in_addr);
342 #else
343 	if (j->ip4s > 0)
344 		return (EINVAL);
345 #endif
346 #ifdef INET6
347 	if (j->ip6s > jail_max_af_ips)
348 		return (EINVAL);
349 	tmplen += j->ip6s * sizeof(struct in6_addr);
350 #else
351 	if (j->ip6s > 0)
352 		return (EINVAL);
353 #endif
354 	u_path = malloc(tmplen, M_TEMP, M_WAITOK);
355 	u_hostname = u_path + MAXPATHLEN;
356 	u_name = u_hostname + MAXHOSTNAMELEN;
357 #ifdef INET
358 	u_ip4 = (struct in_addr *)(u_name + MAXHOSTNAMELEN);
359 #endif
360 #ifdef INET6
361 #ifdef INET
362 	u_ip6 = (struct in6_addr *)(u_ip4 + ip4s);
363 #else
364 	u_ip6 = (struct in6_addr *)(u_name + MAXHOSTNAMELEN);
365 #endif
366 #endif
367 	optiov[opt.uio_iovcnt].iov_base = "path";
368 	optiov[opt.uio_iovcnt].iov_len = sizeof("path");
369 	opt.uio_iovcnt++;
370 	optiov[opt.uio_iovcnt].iov_base = u_path;
371 	error = copyinstr(j->path, u_path, MAXPATHLEN,
372 	    &optiov[opt.uio_iovcnt].iov_len);
373 	if (error) {
374 		free(u_path, M_TEMP);
375 		return (error);
376 	}
377 	opt.uio_iovcnt++;
378 	optiov[opt.uio_iovcnt].iov_base = "host.hostname";
379 	optiov[opt.uio_iovcnt].iov_len = sizeof("host.hostname");
380 	opt.uio_iovcnt++;
381 	optiov[opt.uio_iovcnt].iov_base = u_hostname;
382 	error = copyinstr(j->hostname, u_hostname, MAXHOSTNAMELEN,
383 	    &optiov[opt.uio_iovcnt].iov_len);
384 	if (error) {
385 		free(u_path, M_TEMP);
386 		return (error);
387 	}
388 	opt.uio_iovcnt++;
389 	if (j->jailname != NULL) {
390 		optiov[opt.uio_iovcnt].iov_base = "name";
391 		optiov[opt.uio_iovcnt].iov_len = sizeof("name");
392 		opt.uio_iovcnt++;
393 		optiov[opt.uio_iovcnt].iov_base = u_name;
394 		error = copyinstr(j->jailname, u_name, MAXHOSTNAMELEN,
395 		    &optiov[opt.uio_iovcnt].iov_len);
396 		if (error) {
397 			free(u_path, M_TEMP);
398 			return (error);
399 		}
400 		opt.uio_iovcnt++;
401 	}
402 #ifdef INET
403 	optiov[opt.uio_iovcnt].iov_base = "ip4.addr";
404 	optiov[opt.uio_iovcnt].iov_len = sizeof("ip4.addr");
405 	opt.uio_iovcnt++;
406 	optiov[opt.uio_iovcnt].iov_base = u_ip4;
407 	optiov[opt.uio_iovcnt].iov_len = ip4s * sizeof(struct in_addr);
408 	if (j->version == 0)
409 		u_ip4->s_addr = j->ip4s;
410 	else {
411 		error = copyin(j->ip4, u_ip4, optiov[opt.uio_iovcnt].iov_len);
412 		if (error) {
413 			free(u_path, M_TEMP);
414 			return (error);
415 		}
416 	}
417 	opt.uio_iovcnt++;
418 #endif
419 #ifdef INET6
420 	optiov[opt.uio_iovcnt].iov_base = "ip6.addr";
421 	optiov[opt.uio_iovcnt].iov_len = sizeof("ip6.addr");
422 	opt.uio_iovcnt++;
423 	optiov[opt.uio_iovcnt].iov_base = u_ip6;
424 	optiov[opt.uio_iovcnt].iov_len = j->ip6s * sizeof(struct in6_addr);
425 	error = copyin(j->ip6, u_ip6, optiov[opt.uio_iovcnt].iov_len);
426 	if (error) {
427 		free(u_path, M_TEMP);
428 		return (error);
429 	}
430 	opt.uio_iovcnt++;
431 #endif
432 	KASSERT(opt.uio_iovcnt <= nitems(optiov),
433 		("kern_jail: too many iovecs (%d)", opt.uio_iovcnt));
434 	error = kern_jail_set(td, &opt, JAIL_CREATE | JAIL_ATTACH);
435 	free(u_path, M_TEMP);
436 	return (error);
437 }
438 
439 /*
440  * struct jail_set_args {
441  *	struct iovec *iovp;
442  *	unsigned int iovcnt;
443  *	int flags;
444  * };
445  */
446 int
447 sys_jail_set(struct thread *td, struct jail_set_args *uap)
448 {
449 	struct uio *auio;
450 	int error;
451 
452 	/* Check that we have an even number of iovecs. */
453 	if (uap->iovcnt & 1)
454 		return (EINVAL);
455 
456 	error = copyinuio(uap->iovp, uap->iovcnt, &auio);
457 	if (error)
458 		return (error);
459 	error = kern_jail_set(td, auio, uap->flags);
460 	free(auio, M_IOV);
461 	return (error);
462 }
463 
464 int
465 kern_jail_set(struct thread *td, struct uio *optuio, int flags)
466 {
467 	struct nameidata nd;
468 #ifdef INET
469 	struct in_addr *ip4;
470 #endif
471 #ifdef INET6
472 	struct in6_addr *ip6;
473 #endif
474 	struct vfsopt *opt;
475 	struct vfsoptlist *opts;
476 	struct prison *pr, *deadpr, *mypr, *ppr, *tpr;
477 	struct vnode *root;
478 	char *domain, *errmsg, *host, *name, *namelc, *p, *path, *uuid;
479 	char *g_path, *osrelstr;
480 	struct bool_flags *bf;
481 	struct jailsys_flags *jsf;
482 #if defined(INET) || defined(INET6)
483 	struct prison *tppr;
484 	void *op;
485 #endif
486 	unsigned long hid;
487 	size_t namelen, onamelen, pnamelen;
488 	int born, created, cuflags, descend, enforce;
489 	int error, errmsg_len, errmsg_pos;
490 	int gotchildmax, gotenforce, gothid, gotrsnum, gotslevel;
491 	int jid, jsys, len, level;
492 	int childmax, osreldt, rsnum, slevel;
493 #if defined(INET) || defined(INET6)
494 	int ii, ij;
495 #endif
496 #ifdef INET
497 	int ip4s, redo_ip4;
498 #endif
499 #ifdef INET6
500 	int ip6s, redo_ip6;
501 #endif
502 	uint64_t pr_allow, ch_allow, pr_flags, ch_flags;
503 	uint64_t pr_allow_diff;
504 	unsigned tallow;
505 	char numbuf[12];
506 
507 	error = priv_check(td, PRIV_JAIL_SET);
508 	if (!error && (flags & JAIL_ATTACH))
509 		error = priv_check(td, PRIV_JAIL_ATTACH);
510 	if (error)
511 		return (error);
512 	mypr = td->td_ucred->cr_prison;
513 	if ((flags & JAIL_CREATE) && mypr->pr_childmax == 0)
514 		return (EPERM);
515 	if (flags & ~JAIL_SET_MASK)
516 		return (EINVAL);
517 
518 	/*
519 	 * Check all the parameters before committing to anything.  Not all
520 	 * errors can be caught early, but we may as well try.  Also, this
521 	 * takes care of some expensive stuff (path lookup) before getting
522 	 * the allprison lock.
523 	 *
524 	 * XXX Jails are not filesystems, and jail parameters are not mount
525 	 *     options.  But it makes more sense to re-use the vfsopt code
526 	 *     than duplicate it under a different name.
527 	 */
528 	error = vfs_buildopts(optuio, &opts);
529 	if (error)
530 		return (error);
531 #ifdef INET
532 	ip4 = NULL;
533 #endif
534 #ifdef INET6
535 	ip6 = NULL;
536 #endif
537 	g_path = NULL;
538 
539 	cuflags = flags & (JAIL_CREATE | JAIL_UPDATE);
540 	if (!cuflags) {
541 		error = EINVAL;
542 		vfs_opterror(opts, "no valid operation (create or update)");
543 		goto done_errmsg;
544 	}
545 
546 	error = vfs_copyopt(opts, "jid", &jid, sizeof(jid));
547 	if (error == ENOENT)
548 		jid = 0;
549 	else if (error != 0)
550 		goto done_free;
551 
552 	error = vfs_copyopt(opts, "securelevel", &slevel, sizeof(slevel));
553 	if (error == ENOENT)
554 		gotslevel = 0;
555 	else if (error != 0)
556 		goto done_free;
557 	else
558 		gotslevel = 1;
559 
560 	error =
561 	    vfs_copyopt(opts, "children.max", &childmax, sizeof(childmax));
562 	if (error == ENOENT)
563 		gotchildmax = 0;
564 	else if (error != 0)
565 		goto done_free;
566 	else
567 		gotchildmax = 1;
568 
569 	error = vfs_copyopt(opts, "enforce_statfs", &enforce, sizeof(enforce));
570 	if (error == ENOENT)
571 		gotenforce = 0;
572 	else if (error != 0)
573 		goto done_free;
574 	else if (enforce < 0 || enforce > 2) {
575 		error = EINVAL;
576 		goto done_free;
577 	} else
578 		gotenforce = 1;
579 
580 	error = vfs_copyopt(opts, "devfs_ruleset", &rsnum, sizeof(rsnum));
581 	if (error == ENOENT)
582 		gotrsnum = 0;
583 	else if (error != 0)
584 		goto done_free;
585 	else
586 		gotrsnum = 1;
587 
588 	pr_flags = ch_flags = 0;
589 	for (bf = pr_flag_bool;
590 	     bf < pr_flag_bool + nitems(pr_flag_bool);
591 	     bf++) {
592 		vfs_flagopt(opts, bf->name, &pr_flags, bf->flag);
593 		vfs_flagopt(opts, bf->noname, &ch_flags, bf->flag);
594 	}
595 	ch_flags |= pr_flags;
596 	for (jsf = pr_flag_jailsys;
597 	     jsf < pr_flag_jailsys + nitems(pr_flag_jailsys);
598 	     jsf++) {
599 		error = vfs_copyopt(opts, jsf->name, &jsys, sizeof(jsys));
600 		if (error == ENOENT)
601 			continue;
602 		if (error != 0)
603 			goto done_free;
604 		switch (jsys) {
605 		case JAIL_SYS_DISABLE:
606 			if (!jsf->disable) {
607 				error = EINVAL;
608 				goto done_free;
609 			}
610 			pr_flags |= jsf->disable;
611 			break;
612 		case JAIL_SYS_NEW:
613 			pr_flags |= jsf->new;
614 			break;
615 		case JAIL_SYS_INHERIT:
616 			break;
617 		default:
618 			error = EINVAL;
619 			goto done_free;
620 		}
621 		ch_flags |= jsf->new | jsf->disable;
622 	}
623 	if ((flags & (JAIL_CREATE | JAIL_UPDATE | JAIL_ATTACH)) == JAIL_CREATE
624 	    && !(pr_flags & PR_PERSIST)) {
625 		error = EINVAL;
626 		vfs_opterror(opts, "new jail must persist or attach");
627 		goto done_errmsg;
628 	}
629 #ifdef VIMAGE
630 	if ((flags & JAIL_UPDATE) && (ch_flags & PR_VNET)) {
631 		error = EINVAL;
632 		vfs_opterror(opts, "vnet cannot be changed after creation");
633 		goto done_errmsg;
634 	}
635 #endif
636 #ifdef INET
637 	if ((flags & JAIL_UPDATE) && (ch_flags & PR_IP4_USER)) {
638 		error = EINVAL;
639 		vfs_opterror(opts, "ip4 cannot be changed after creation");
640 		goto done_errmsg;
641 	}
642 #endif
643 #ifdef INET6
644 	if ((flags & JAIL_UPDATE) && (ch_flags & PR_IP6_USER)) {
645 		error = EINVAL;
646 		vfs_opterror(opts, "ip6 cannot be changed after creation");
647 		goto done_errmsg;
648 	}
649 #endif
650 
651 	pr_allow = ch_allow = 0;
652 	for (bf = pr_flag_allow;
653 	     bf < pr_flag_allow + nitems(pr_flag_allow) && bf->flag != 0;
654 	     bf++) {
655 		vfs_flagopt(opts, bf->name, &pr_allow, bf->flag);
656 		vfs_flagopt(opts, bf->noname, &ch_allow, bf->flag);
657 	}
658 	ch_allow |= pr_allow;
659 
660 	error = vfs_getopt(opts, "name", (void **)&name, &len);
661 	if (error == ENOENT)
662 		name = NULL;
663 	else if (error != 0)
664 		goto done_free;
665 	else {
666 		if (len == 0 || name[len - 1] != '\0') {
667 			error = EINVAL;
668 			goto done_free;
669 		}
670 		if (len > MAXHOSTNAMELEN) {
671 			error = ENAMETOOLONG;
672 			goto done_free;
673 		}
674 	}
675 
676 	error = vfs_getopt(opts, "host.hostname", (void **)&host, &len);
677 	if (error == ENOENT)
678 		host = NULL;
679 	else if (error != 0)
680 		goto done_free;
681 	else {
682 		ch_flags |= PR_HOST;
683 		pr_flags |= PR_HOST;
684 		if (len == 0 || host[len - 1] != '\0') {
685 			error = EINVAL;
686 			goto done_free;
687 		}
688 		if (len > MAXHOSTNAMELEN) {
689 			error = ENAMETOOLONG;
690 			goto done_free;
691 		}
692 	}
693 
694 	error = vfs_getopt(opts, "host.domainname", (void **)&domain, &len);
695 	if (error == ENOENT)
696 		domain = NULL;
697 	else if (error != 0)
698 		goto done_free;
699 	else {
700 		ch_flags |= PR_HOST;
701 		pr_flags |= PR_HOST;
702 		if (len == 0 || domain[len - 1] != '\0') {
703 			error = EINVAL;
704 			goto done_free;
705 		}
706 		if (len > MAXHOSTNAMELEN) {
707 			error = ENAMETOOLONG;
708 			goto done_free;
709 		}
710 	}
711 
712 	error = vfs_getopt(opts, "host.hostuuid", (void **)&uuid, &len);
713 	if (error == ENOENT)
714 		uuid = NULL;
715 	else if (error != 0)
716 		goto done_free;
717 	else {
718 		ch_flags |= PR_HOST;
719 		pr_flags |= PR_HOST;
720 		if (len == 0 || uuid[len - 1] != '\0') {
721 			error = EINVAL;
722 			goto done_free;
723 		}
724 		if (len > HOSTUUIDLEN) {
725 			error = ENAMETOOLONG;
726 			goto done_free;
727 		}
728 	}
729 
730 #ifdef COMPAT_FREEBSD32
731 	if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
732 		uint32_t hid32;
733 
734 		error = vfs_copyopt(opts, "host.hostid", &hid32, sizeof(hid32));
735 		hid = hid32;
736 	} else
737 #endif
738 		error = vfs_copyopt(opts, "host.hostid", &hid, sizeof(hid));
739 	if (error == ENOENT)
740 		gothid = 0;
741 	else if (error != 0)
742 		goto done_free;
743 	else {
744 		gothid = 1;
745 		ch_flags |= PR_HOST;
746 		pr_flags |= PR_HOST;
747 	}
748 
749 #ifdef INET
750 	error = vfs_getopt(opts, "ip4.addr", &op, &ip4s);
751 	if (error == ENOENT)
752 		ip4s = 0;
753 	else if (error != 0)
754 		goto done_free;
755 	else if (ip4s & (sizeof(*ip4) - 1)) {
756 		error = EINVAL;
757 		goto done_free;
758 	} else {
759 		ch_flags |= PR_IP4_USER;
760 		pr_flags |= PR_IP4_USER;
761 		if (ip4s > 0) {
762 			ip4s /= sizeof(*ip4);
763 			if (ip4s > jail_max_af_ips) {
764 				error = EINVAL;
765 				vfs_opterror(opts, "too many IPv4 addresses");
766 				goto done_errmsg;
767 			}
768 			ip4 = malloc(ip4s * sizeof(*ip4), M_PRISON, M_WAITOK);
769 			bcopy(op, ip4, ip4s * sizeof(*ip4));
770 			/*
771 			 * IP addresses are all sorted but ip[0] to preserve
772 			 * the primary IP address as given from userland.
773 			 * This special IP is used for unbound outgoing
774 			 * connections as well for "loopback" traffic in case
775 			 * source address selection cannot find any more fitting
776 			 * address to connect from.
777 			 */
778 			if (ip4s > 1)
779 				qsort(ip4 + 1, ip4s - 1, sizeof(*ip4),
780 				    prison_qcmp_v4);
781 			/*
782 			 * Check for duplicate addresses and do some simple
783 			 * zero and broadcast checks. If users give other bogus
784 			 * addresses it is their problem.
785 			 *
786 			 * We do not have to care about byte order for these
787 			 * checks so we will do them in NBO.
788 			 */
789 			for (ii = 0; ii < ip4s; ii++) {
790 				if (ip4[ii].s_addr == INADDR_ANY ||
791 				    ip4[ii].s_addr == INADDR_BROADCAST) {
792 					error = EINVAL;
793 					goto done_free;
794 				}
795 				if ((ii+1) < ip4s &&
796 				    (ip4[0].s_addr == ip4[ii+1].s_addr ||
797 				     ip4[ii].s_addr == ip4[ii+1].s_addr)) {
798 					error = EINVAL;
799 					goto done_free;
800 				}
801 			}
802 		}
803 	}
804 #endif
805 
806 #ifdef INET6
807 	error = vfs_getopt(opts, "ip6.addr", &op, &ip6s);
808 	if (error == ENOENT)
809 		ip6s = 0;
810 	else if (error != 0)
811 		goto done_free;
812 	else if (ip6s & (sizeof(*ip6) - 1)) {
813 		error = EINVAL;
814 		goto done_free;
815 	} else {
816 		ch_flags |= PR_IP6_USER;
817 		pr_flags |= PR_IP6_USER;
818 		if (ip6s > 0) {
819 			ip6s /= sizeof(*ip6);
820 			if (ip6s > jail_max_af_ips) {
821 				error = EINVAL;
822 				vfs_opterror(opts, "too many IPv6 addresses");
823 				goto done_errmsg;
824 			}
825 			ip6 = malloc(ip6s * sizeof(*ip6), M_PRISON, M_WAITOK);
826 			bcopy(op, ip6, ip6s * sizeof(*ip6));
827 			if (ip6s > 1)
828 				qsort(ip6 + 1, ip6s - 1, sizeof(*ip6),
829 				    prison_qcmp_v6);
830 			for (ii = 0; ii < ip6s; ii++) {
831 				if (IN6_IS_ADDR_UNSPECIFIED(&ip6[ii])) {
832 					error = EINVAL;
833 					goto done_free;
834 				}
835 				if ((ii+1) < ip6s &&
836 				    (IN6_ARE_ADDR_EQUAL(&ip6[0], &ip6[ii+1]) ||
837 				     IN6_ARE_ADDR_EQUAL(&ip6[ii], &ip6[ii+1])))
838 				{
839 					error = EINVAL;
840 					goto done_free;
841 				}
842 			}
843 		}
844 	}
845 #endif
846 
847 #if defined(VIMAGE) && (defined(INET) || defined(INET6))
848 	if ((ch_flags & PR_VNET) && (ch_flags & (PR_IP4_USER | PR_IP6_USER))) {
849 		error = EINVAL;
850 		vfs_opterror(opts,
851 		    "vnet jails cannot have IP address restrictions");
852 		goto done_errmsg;
853 	}
854 #endif
855 
856 	error = vfs_getopt(opts, "osrelease", (void **)&osrelstr, &len);
857 	if (error == ENOENT)
858 		osrelstr = NULL;
859 	else if (error != 0)
860 		goto done_free;
861 	else {
862 		if (flags & JAIL_UPDATE) {
863 			error = EINVAL;
864 			vfs_opterror(opts,
865 			    "osrelease cannot be changed after creation");
866 			goto done_errmsg;
867 		}
868 		if (len == 0 || len >= OSRELEASELEN) {
869 			error = EINVAL;
870 			vfs_opterror(opts,
871 			    "osrelease string must be 1-%d bytes long",
872 			    OSRELEASELEN - 1);
873 			goto done_errmsg;
874 		}
875 	}
876 
877 	error = vfs_copyopt(opts, "osreldate", &osreldt, sizeof(osreldt));
878 	if (error == ENOENT)
879 		osreldt = 0;
880 	else if (error != 0)
881 		goto done_free;
882 	else {
883 		if (flags & JAIL_UPDATE) {
884 			error = EINVAL;
885 			vfs_opterror(opts,
886 			    "osreldate cannot be changed after creation");
887 			goto done_errmsg;
888 		}
889 		if (osreldt == 0) {
890 			error = EINVAL;
891 			vfs_opterror(opts, "osreldate cannot be 0");
892 			goto done_errmsg;
893 		}
894 	}
895 
896 	root = NULL;
897 	error = vfs_getopt(opts, "path", (void **)&path, &len);
898 	if (error == ENOENT)
899 		path = NULL;
900 	else if (error != 0)
901 		goto done_free;
902 	else {
903 		if (flags & JAIL_UPDATE) {
904 			error = EINVAL;
905 			vfs_opterror(opts,
906 			    "path cannot be changed after creation");
907 			goto done_errmsg;
908 		}
909 		if (len == 0 || path[len - 1] != '\0') {
910 			error = EINVAL;
911 			goto done_free;
912 		}
913 		NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE,
914 		    path, td);
915 		error = namei(&nd);
916 		if (error)
917 			goto done_free;
918 		root = nd.ni_vp;
919 		NDFREE(&nd, NDF_ONLY_PNBUF);
920 		g_path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
921 		strlcpy(g_path, path, MAXPATHLEN);
922 		error = vn_path_to_global_path(td, root, g_path, MAXPATHLEN);
923 		if (error == 0) {
924 			path = g_path;
925 		} else {
926 			/* exit on other errors */
927 			goto done_free;
928 		}
929 		if (root->v_type != VDIR) {
930 			error = ENOTDIR;
931 			vput(root);
932 			goto done_free;
933 		}
934 		VOP_UNLOCK(root);
935 	}
936 
937 	/*
938 	 * Find the specified jail, or at least its parent.
939 	 * This abuses the file error codes ENOENT and EEXIST.
940 	 */
941 	pr = NULL;
942 	ppr = mypr;
943 	if (cuflags == JAIL_CREATE && jid == 0 && name != NULL) {
944 		namelc = strrchr(name, '.');
945 		jid = strtoul(namelc != NULL ? namelc + 1 : name, &p, 10);
946 		if (*p != '\0')
947 			jid = 0;
948 	}
949 	sx_xlock(&allprison_lock);
950 	if (jid != 0) {
951 		/*
952 		 * See if a requested jid already exists.  There is an
953 		 * information leak here if the jid exists but is not within
954 		 * the caller's jail hierarchy.  Jail creators will get EEXIST
955 		 * even though they cannot see the jail, and CREATE | UPDATE
956 		 * will return ENOENT which is not normally a valid error.
957 		 */
958 		if (jid < 0) {
959 			error = EINVAL;
960 			vfs_opterror(opts, "negative jid");
961 			goto done_unlock_list;
962 		}
963 		pr = prison_find(jid);
964 		if (pr != NULL) {
965 			ppr = pr->pr_parent;
966 			/* Create: jid must not exist. */
967 			if (cuflags == JAIL_CREATE) {
968 				mtx_unlock(&pr->pr_mtx);
969 				error = EEXIST;
970 				vfs_opterror(opts, "jail %d already exists",
971 				    jid);
972 				goto done_unlock_list;
973 			}
974 			if (!prison_ischild(mypr, pr)) {
975 				mtx_unlock(&pr->pr_mtx);
976 				pr = NULL;
977 			} else if (pr->pr_uref == 0) {
978 				if (!(flags & JAIL_DYING)) {
979 					mtx_unlock(&pr->pr_mtx);
980 					error = ENOENT;
981 					vfs_opterror(opts, "jail %d is dying",
982 					    jid);
983 					goto done_unlock_list;
984 				} else if ((flags & JAIL_ATTACH) ||
985 				    (pr_flags & PR_PERSIST)) {
986 					/*
987 					 * A dying jail might be resurrected
988 					 * (via attach or persist), but first
989 					 * it must determine if another jail
990 					 * has claimed its name.  Accomplish
991 					 * this by implicitly re-setting the
992 					 * name.
993 					 */
994 					if (name == NULL)
995 						name = prison_name(mypr, pr);
996 				}
997 			}
998 		}
999 		if (pr == NULL) {
1000 			/* Update: jid must exist. */
1001 			if (cuflags == JAIL_UPDATE) {
1002 				error = ENOENT;
1003 				vfs_opterror(opts, "jail %d not found", jid);
1004 				goto done_unlock_list;
1005 			}
1006 		}
1007 	}
1008 	/*
1009 	 * If the caller provided a name, look for a jail by that name.
1010 	 * This has different semantics for creates and updates keyed by jid
1011 	 * (where the name must not already exist in a different jail),
1012 	 * and updates keyed by the name itself (where the name must exist
1013 	 * because that is the jail being updated).
1014 	 */
1015 	namelc = NULL;
1016 	if (name != NULL) {
1017 		namelc = strrchr(name, '.');
1018 		if (namelc == NULL)
1019 			namelc = name;
1020 		else {
1021 			/*
1022 			 * This is a hierarchical name.  Split it into the
1023 			 * parent and child names, and make sure the parent
1024 			 * exists or matches an already found jail.
1025 			 */
1026 			if (pr != NULL) {
1027 				if (strncmp(name, ppr->pr_name, namelc - name)
1028 				    || ppr->pr_name[namelc - name] != '\0') {
1029 					mtx_unlock(&pr->pr_mtx);
1030 					error = EINVAL;
1031 					vfs_opterror(opts,
1032 					    "cannot change jail's parent");
1033 					goto done_unlock_list;
1034 				}
1035 			} else {
1036 				*namelc = '\0';
1037 				ppr = prison_find_name(mypr, name);
1038 				if (ppr == NULL) {
1039 					error = ENOENT;
1040 					vfs_opterror(opts,
1041 					    "jail \"%s\" not found", name);
1042 					goto done_unlock_list;
1043 				}
1044 				mtx_unlock(&ppr->pr_mtx);
1045 				*namelc = '.';
1046 			}
1047 			namelc++;
1048 		}
1049 		if (namelc[0] != '\0') {
1050 			pnamelen =
1051 			    (ppr == &prison0) ? 0 : strlen(ppr->pr_name) + 1;
1052  name_again:
1053 			deadpr = NULL;
1054 			FOREACH_PRISON_CHILD(ppr, tpr) {
1055 				if (tpr != pr && tpr->pr_ref > 0 &&
1056 				    !strcmp(tpr->pr_name + pnamelen, namelc)) {
1057 					if (pr == NULL &&
1058 					    cuflags != JAIL_CREATE) {
1059 						mtx_lock(&tpr->pr_mtx);
1060 						if (tpr->pr_ref > 0) {
1061 							/*
1062 							 * Use this jail
1063 							 * for updates.
1064 							 */
1065 							if (tpr->pr_uref > 0) {
1066 								pr = tpr;
1067 								break;
1068 							}
1069 							deadpr = tpr;
1070 						}
1071 						mtx_unlock(&tpr->pr_mtx);
1072 					} else if (tpr->pr_uref > 0) {
1073 						/*
1074 						 * Create, or update(jid):
1075 						 * name must not exist in an
1076 						 * active sibling jail.
1077 						 */
1078 						error = EEXIST;
1079 						if (pr != NULL)
1080 							mtx_unlock(&pr->pr_mtx);
1081 						vfs_opterror(opts,
1082 						   "jail \"%s\" already exists",
1083 						   name);
1084 						goto done_unlock_list;
1085 					}
1086 				}
1087 			}
1088 			/* If no active jail is found, use a dying one. */
1089 			if (deadpr != NULL && pr == NULL) {
1090 				if (flags & JAIL_DYING) {
1091 					mtx_lock(&deadpr->pr_mtx);
1092 					if (deadpr->pr_ref == 0) {
1093 						mtx_unlock(&deadpr->pr_mtx);
1094 						goto name_again;
1095 					}
1096 					pr = deadpr;
1097 				} else if (cuflags == JAIL_UPDATE) {
1098 					error = ENOENT;
1099 					vfs_opterror(opts,
1100 					    "jail \"%s\" is dying", name);
1101 					goto done_unlock_list;
1102 				}
1103 			}
1104 			/* Update: name must exist if no jid. */
1105 			else if (cuflags == JAIL_UPDATE && pr == NULL) {
1106 				error = ENOENT;
1107 				vfs_opterror(opts, "jail \"%s\" not found",
1108 				    name);
1109 				goto done_unlock_list;
1110 			}
1111 		}
1112 	}
1113 	/* Update: must provide a jid or name. */
1114 	else if (cuflags == JAIL_UPDATE && pr == NULL) {
1115 		error = ENOENT;
1116 		vfs_opterror(opts, "update specified no jail");
1117 		goto done_unlock_list;
1118 	}
1119 
1120 	/* If there's no prison to update, create a new one and link it in. */
1121 	if (pr == NULL) {
1122 		for (tpr = mypr; tpr != NULL; tpr = tpr->pr_parent)
1123 			if (tpr->pr_childcount >= tpr->pr_childmax) {
1124 				error = EPERM;
1125 				vfs_opterror(opts, "prison limit exceeded");
1126 				goto done_unlock_list;
1127 			}
1128 		created = 1;
1129 		mtx_lock(&ppr->pr_mtx);
1130 		if (ppr->pr_ref == 0) {
1131 			mtx_unlock(&ppr->pr_mtx);
1132 			error = ENOENT;
1133 			vfs_opterror(opts, "jail \"%s\" not found",
1134 			    prison_name(mypr, ppr));
1135 			goto done_unlock_list;
1136 		}
1137 		ppr->pr_ref++;
1138 		ppr->pr_uref++;
1139 		mtx_unlock(&ppr->pr_mtx);
1140 		pr = malloc(sizeof(*pr), M_PRISON, M_WAITOK | M_ZERO);
1141 		if (jid == 0) {
1142 			/* Find the next free jid. */
1143 			jid = lastprid + 1;
1144  findnext:
1145 			if (jid == JAIL_MAX)
1146 				jid = 1;
1147 			TAILQ_FOREACH(tpr, &allprison, pr_list) {
1148 				if (tpr->pr_id < jid)
1149 					continue;
1150 				if (tpr->pr_id > jid || tpr->pr_ref == 0) {
1151 					TAILQ_INSERT_BEFORE(tpr, pr, pr_list);
1152 					break;
1153 				}
1154 				if (jid == lastprid) {
1155 					error = EAGAIN;
1156 					vfs_opterror(opts,
1157 					    "no available jail IDs");
1158 					free(pr, M_PRISON);
1159 					prison_deref(ppr, PD_DEREF |
1160 					    PD_DEUREF | PD_LIST_XLOCKED);
1161 					goto done_releroot;
1162 				}
1163 				jid++;
1164 				goto findnext;
1165 			}
1166 			lastprid = jid;
1167 		} else {
1168 			/*
1169 			 * The jail already has a jid (that did not yet exist),
1170 			 * so just find where to insert it.
1171 			 */
1172 			TAILQ_FOREACH(tpr, &allprison, pr_list)
1173 				if (tpr->pr_id >= jid) {
1174 					TAILQ_INSERT_BEFORE(tpr, pr, pr_list);
1175 					break;
1176 				}
1177 		}
1178 		if (tpr == NULL)
1179 			TAILQ_INSERT_TAIL(&allprison, pr, pr_list);
1180 		LIST_INSERT_HEAD(&ppr->pr_children, pr, pr_sibling);
1181 		for (tpr = ppr; tpr != NULL; tpr = tpr->pr_parent)
1182 			tpr->pr_childcount++;
1183 
1184 		pr->pr_parent = ppr;
1185 		pr->pr_id = jid;
1186 
1187 		/* Set some default values, and inherit some from the parent. */
1188 		if (namelc == NULL)
1189 			namelc = "";
1190 		if (path == NULL) {
1191 			path = "/";
1192 			root = mypr->pr_root;
1193 			vref(root);
1194 		}
1195 		strlcpy(pr->pr_hostuuid, DEFAULT_HOSTUUID, HOSTUUIDLEN);
1196 		pr->pr_flags |= PR_HOST;
1197 #if defined(INET) || defined(INET6)
1198 #ifdef VIMAGE
1199 		if (!(pr_flags & PR_VNET))
1200 #endif
1201 		{
1202 #ifdef INET
1203 			if (!(ch_flags & PR_IP4_USER))
1204 				pr->pr_flags |= PR_IP4 | PR_IP4_USER;
1205 			else if (!(pr_flags & PR_IP4_USER)) {
1206 				pr->pr_flags |= ppr->pr_flags & PR_IP4;
1207 				if (ppr->pr_ip4 != NULL) {
1208 					pr->pr_ip4s = ppr->pr_ip4s;
1209 					pr->pr_ip4 = malloc(pr->pr_ip4s *
1210 					    sizeof(struct in_addr), M_PRISON,
1211 					    M_WAITOK);
1212 					bcopy(ppr->pr_ip4, pr->pr_ip4,
1213 					    pr->pr_ip4s * sizeof(*pr->pr_ip4));
1214 				}
1215 			}
1216 #endif
1217 #ifdef INET6
1218 			if (!(ch_flags & PR_IP6_USER))
1219 				pr->pr_flags |= PR_IP6 | PR_IP6_USER;
1220 			else if (!(pr_flags & PR_IP6_USER)) {
1221 				pr->pr_flags |= ppr->pr_flags & PR_IP6;
1222 				if (ppr->pr_ip6 != NULL) {
1223 					pr->pr_ip6s = ppr->pr_ip6s;
1224 					pr->pr_ip6 = malloc(pr->pr_ip6s *
1225 					    sizeof(struct in6_addr), M_PRISON,
1226 					    M_WAITOK);
1227 					bcopy(ppr->pr_ip6, pr->pr_ip6,
1228 					    pr->pr_ip6s * sizeof(*pr->pr_ip6));
1229 				}
1230 			}
1231 #endif
1232 		}
1233 #endif
1234 		/* Source address selection is always on by default. */
1235 		pr->pr_flags |= _PR_IP_SADDRSEL;
1236 
1237 		pr->pr_securelevel = ppr->pr_securelevel;
1238 		pr->pr_allow = JAIL_DEFAULT_ALLOW & ppr->pr_allow;
1239 		pr->pr_enforce_statfs = jail_default_enforce_statfs;
1240 		pr->pr_devfs_rsnum = ppr->pr_devfs_rsnum;
1241 
1242 		pr->pr_osreldate = osreldt ? osreldt : ppr->pr_osreldate;
1243 		if (osrelstr == NULL)
1244 		    strcpy(pr->pr_osrelease, ppr->pr_osrelease);
1245 		else
1246 		    strcpy(pr->pr_osrelease, osrelstr);
1247 
1248 		LIST_INIT(&pr->pr_children);
1249 		mtx_init(&pr->pr_mtx, "jail mutex", NULL, MTX_DEF | MTX_DUPOK);
1250 		TASK_INIT(&pr->pr_task, 0, prison_complete, pr);
1251 
1252 #ifdef VIMAGE
1253 		/* Allocate a new vnet if specified. */
1254 		pr->pr_vnet = (pr_flags & PR_VNET)
1255 		    ? vnet_alloc() : ppr->pr_vnet;
1256 #endif
1257 		/*
1258 		 * Allocate a dedicated cpuset for each jail.
1259 		 * Unlike other initial settings, this may return an erorr.
1260 		 */
1261 		error = cpuset_create_root(ppr, &pr->pr_cpuset);
1262 		if (error) {
1263 			prison_deref(pr, PD_LIST_XLOCKED);
1264 			goto done_releroot;
1265 		}
1266 
1267 		mtx_lock(&pr->pr_mtx);
1268 		/*
1269 		 * New prisons do not yet have a reference, because we do not
1270 		 * want others to see the incomplete prison once the
1271 		 * allprison_lock is downgraded.
1272 		 */
1273 	} else {
1274 		created = 0;
1275 		/*
1276 		 * Grab a reference for existing prisons, to ensure they
1277 		 * continue to exist for the duration of the call.
1278 		 */
1279 		pr->pr_ref++;
1280 #if defined(VIMAGE) && (defined(INET) || defined(INET6))
1281 		if ((pr->pr_flags & PR_VNET) &&
1282 		    (ch_flags & (PR_IP4_USER | PR_IP6_USER))) {
1283 			error = EINVAL;
1284 			vfs_opterror(opts,
1285 			    "vnet jails cannot have IP address restrictions");
1286 			goto done_deref_locked;
1287 		}
1288 #endif
1289 #ifdef INET
1290 		if (PR_IP4_USER & ch_flags & (pr_flags ^ pr->pr_flags)) {
1291 			error = EINVAL;
1292 			vfs_opterror(opts,
1293 			    "ip4 cannot be changed after creation");
1294 			goto done_deref_locked;
1295 		}
1296 #endif
1297 #ifdef INET6
1298 		if (PR_IP6_USER & ch_flags & (pr_flags ^ pr->pr_flags)) {
1299 			error = EINVAL;
1300 			vfs_opterror(opts,
1301 			    "ip6 cannot be changed after creation");
1302 			goto done_deref_locked;
1303 		}
1304 #endif
1305 	}
1306 
1307 	/* Do final error checking before setting anything. */
1308 	if (gotslevel) {
1309 		if (slevel < ppr->pr_securelevel) {
1310 			error = EPERM;
1311 			goto done_deref_locked;
1312 		}
1313 	}
1314 	if (gotchildmax) {
1315 		if (childmax >= ppr->pr_childmax) {
1316 			error = EPERM;
1317 			goto done_deref_locked;
1318 		}
1319 	}
1320 	if (gotenforce) {
1321 		if (enforce < ppr->pr_enforce_statfs) {
1322 			error = EPERM;
1323 			goto done_deref_locked;
1324 		}
1325 	}
1326 	if (gotrsnum) {
1327 		/*
1328 		 * devfs_rsnum is a uint16_t
1329 		 */
1330 		if (rsnum < 0 || rsnum > 65535) {
1331 			error = EINVAL;
1332 			goto done_deref_locked;
1333 		}
1334 		/*
1335 		 * Nested jails always inherit parent's devfs ruleset
1336 		 */
1337 		if (jailed(td->td_ucred)) {
1338 			if (rsnum > 0 && rsnum != ppr->pr_devfs_rsnum) {
1339 				error = EPERM;
1340 				goto done_deref_locked;
1341 			} else
1342 				rsnum = ppr->pr_devfs_rsnum;
1343 		}
1344 	}
1345 #ifdef INET
1346 	if (ip4s > 0) {
1347 		if (ppr->pr_flags & PR_IP4) {
1348 			/*
1349 			 * Make sure the new set of IP addresses is a
1350 			 * subset of the parent's list.  Don't worry
1351 			 * about the parent being unlocked, as any
1352 			 * setting is done with allprison_lock held.
1353 			 */
1354 			for (ij = 0; ij < ppr->pr_ip4s; ij++)
1355 				if (ip4[0].s_addr == ppr->pr_ip4[ij].s_addr)
1356 					break;
1357 			if (ij == ppr->pr_ip4s) {
1358 				error = EPERM;
1359 				goto done_deref_locked;
1360 			}
1361 			if (ip4s > 1) {
1362 				for (ii = ij = 1; ii < ip4s; ii++) {
1363 					if (ip4[ii].s_addr ==
1364 					    ppr->pr_ip4[0].s_addr)
1365 						continue;
1366 					for (; ij < ppr->pr_ip4s; ij++)
1367 						if (ip4[ii].s_addr ==
1368 						    ppr->pr_ip4[ij].s_addr)
1369 							break;
1370 					if (ij == ppr->pr_ip4s)
1371 						break;
1372 				}
1373 				if (ij == ppr->pr_ip4s) {
1374 					error = EPERM;
1375 					goto done_deref_locked;
1376 				}
1377 			}
1378 		}
1379 		/*
1380 		 * Check for conflicting IP addresses.  We permit them
1381 		 * if there is no more than one IP on each jail.  If
1382 		 * there is a duplicate on a jail with more than one
1383 		 * IP stop checking and return error.
1384 		 */
1385 #ifdef VIMAGE
1386 		for (tppr = ppr; tppr != &prison0; tppr = tppr->pr_parent)
1387 			if (tppr->pr_flags & PR_VNET)
1388 				break;
1389 #else
1390 		tppr = &prison0;
1391 #endif
1392 		FOREACH_PRISON_DESCENDANT(tppr, tpr, descend) {
1393 			if (tpr == pr ||
1394 #ifdef VIMAGE
1395 			    (tpr != tppr && (tpr->pr_flags & PR_VNET)) ||
1396 #endif
1397 			    tpr->pr_uref == 0) {
1398 				descend = 0;
1399 				continue;
1400 			}
1401 			if (!(tpr->pr_flags & PR_IP4_USER))
1402 				continue;
1403 			descend = 0;
1404 			if (tpr->pr_ip4 == NULL ||
1405 			    (ip4s == 1 && tpr->pr_ip4s == 1))
1406 				continue;
1407 			for (ii = 0; ii < ip4s; ii++) {
1408 				if (prison_check_ip4_locked(tpr, &ip4[ii]) ==
1409 				    0) {
1410 					error = EADDRINUSE;
1411 					vfs_opterror(opts,
1412 					    "IPv4 addresses clash");
1413 					goto done_deref_locked;
1414 				}
1415 			}
1416 		}
1417 	}
1418 #endif
1419 #ifdef INET6
1420 	if (ip6s > 0) {
1421 		if (ppr->pr_flags & PR_IP6) {
1422 			/*
1423 			 * Make sure the new set of IP addresses is a
1424 			 * subset of the parent's list.
1425 			 */
1426 			for (ij = 0; ij < ppr->pr_ip6s; ij++)
1427 				if (IN6_ARE_ADDR_EQUAL(&ip6[0],
1428 				    &ppr->pr_ip6[ij]))
1429 					break;
1430 			if (ij == ppr->pr_ip6s) {
1431 				error = EPERM;
1432 				goto done_deref_locked;
1433 			}
1434 			if (ip6s > 1) {
1435 				for (ii = ij = 1; ii < ip6s; ii++) {
1436 					if (IN6_ARE_ADDR_EQUAL(&ip6[ii],
1437 					     &ppr->pr_ip6[0]))
1438 						continue;
1439 					for (; ij < ppr->pr_ip6s; ij++)
1440 						if (IN6_ARE_ADDR_EQUAL(
1441 						    &ip6[ii], &ppr->pr_ip6[ij]))
1442 							break;
1443 					if (ij == ppr->pr_ip6s)
1444 						break;
1445 				}
1446 				if (ij == ppr->pr_ip6s) {
1447 					error = EPERM;
1448 					goto done_deref_locked;
1449 				}
1450 			}
1451 		}
1452 		/* Check for conflicting IP addresses. */
1453 #ifdef VIMAGE
1454 		for (tppr = ppr; tppr != &prison0; tppr = tppr->pr_parent)
1455 			if (tppr->pr_flags & PR_VNET)
1456 				break;
1457 #else
1458 		tppr = &prison0;
1459 #endif
1460 		FOREACH_PRISON_DESCENDANT(tppr, tpr, descend) {
1461 			if (tpr == pr ||
1462 #ifdef VIMAGE
1463 			    (tpr != tppr && (tpr->pr_flags & PR_VNET)) ||
1464 #endif
1465 			    tpr->pr_uref == 0) {
1466 				descend = 0;
1467 				continue;
1468 			}
1469 			if (!(tpr->pr_flags & PR_IP6_USER))
1470 				continue;
1471 			descend = 0;
1472 			if (tpr->pr_ip6 == NULL ||
1473 			    (ip6s == 1 && tpr->pr_ip6s == 1))
1474 				continue;
1475 			for (ii = 0; ii < ip6s; ii++) {
1476 				if (prison_check_ip6_locked(tpr, &ip6[ii]) ==
1477 				    0) {
1478 					error = EADDRINUSE;
1479 					vfs_opterror(opts,
1480 					    "IPv6 addresses clash");
1481 					goto done_deref_locked;
1482 				}
1483 			}
1484 		}
1485 	}
1486 #endif
1487 	onamelen = namelen = 0;
1488 	if (namelc != NULL) {
1489 		/* Give a default name of the jid.  Also allow the name to be
1490 		 * explicitly the jid - but not any other number, and only in
1491 		 * normal form (no leading zero/etc).
1492 		 */
1493 		if (namelc[0] == '\0')
1494 			snprintf(namelc = numbuf, sizeof(numbuf), "%d", jid);
1495 		else if ((strtoul(namelc, &p, 10) != jid ||
1496 			  namelc[0] < '1' || namelc[0] > '9') && *p == '\0') {
1497 			error = EINVAL;
1498 			vfs_opterror(opts,
1499 			    "name cannot be numeric (unless it is the jid)");
1500 			goto done_deref_locked;
1501 		}
1502 		/*
1503 		 * Make sure the name isn't too long for the prison or its
1504 		 * children.
1505 		 */
1506 		pnamelen = (ppr == &prison0) ? 0 : strlen(ppr->pr_name) + 1;
1507 		onamelen = strlen(pr->pr_name + pnamelen);
1508 		namelen = strlen(namelc);
1509 		if (pnamelen + namelen + 1 > sizeof(pr->pr_name)) {
1510 			error = ENAMETOOLONG;
1511 			goto done_deref_locked;
1512 		}
1513 		FOREACH_PRISON_DESCENDANT(pr, tpr, descend) {
1514 			if (strlen(tpr->pr_name) + (namelen - onamelen) >=
1515 			    sizeof(pr->pr_name)) {
1516 				error = ENAMETOOLONG;
1517 				goto done_deref_locked;
1518 			}
1519 		}
1520 	}
1521 	pr_allow_diff = pr_allow & ~ppr->pr_allow;
1522 	if (pr_allow_diff & ~PR_ALLOW_DIFFERENCES) {
1523 		error = EPERM;
1524 		goto done_deref_locked;
1525 	}
1526 
1527 	/*
1528 	 * Let modules check their parameters.  This requires unlocking and
1529 	 * then re-locking the prison, but this is still a valid state as long
1530 	 * as allprison_lock remains xlocked.
1531 	 */
1532 	mtx_unlock(&pr->pr_mtx);
1533 	error = osd_jail_call(pr, PR_METHOD_CHECK, opts);
1534 	if (error != 0) {
1535 		prison_deref(pr, created
1536 		    ? PD_LIST_XLOCKED
1537 		    : PD_DEREF | PD_LIST_XLOCKED);
1538 		goto done_releroot;
1539 	}
1540 	mtx_lock(&pr->pr_mtx);
1541 
1542 	/* At this point, all valid parameters should have been noted. */
1543 	TAILQ_FOREACH(opt, opts, link) {
1544 		if (!opt->seen && strcmp(opt->name, "errmsg")) {
1545 			error = EINVAL;
1546 			vfs_opterror(opts, "unknown parameter: %s", opt->name);
1547 			goto done_deref_locked;
1548 		}
1549 	}
1550 
1551 	/* Set the parameters of the prison. */
1552 #ifdef INET
1553 	redo_ip4 = 0;
1554 	if (pr_flags & PR_IP4_USER) {
1555 		pr->pr_flags |= PR_IP4;
1556 		free(pr->pr_ip4, M_PRISON);
1557 		pr->pr_ip4s = ip4s;
1558 		pr->pr_ip4 = ip4;
1559 		ip4 = NULL;
1560 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
1561 #ifdef VIMAGE
1562 			if (tpr->pr_flags & PR_VNET) {
1563 				descend = 0;
1564 				continue;
1565 			}
1566 #endif
1567 			if (prison_restrict_ip4(tpr, NULL)) {
1568 				redo_ip4 = 1;
1569 				descend = 0;
1570 			}
1571 		}
1572 	}
1573 #endif
1574 #ifdef INET6
1575 	redo_ip6 = 0;
1576 	if (pr_flags & PR_IP6_USER) {
1577 		pr->pr_flags |= PR_IP6;
1578 		free(pr->pr_ip6, M_PRISON);
1579 		pr->pr_ip6s = ip6s;
1580 		pr->pr_ip6 = ip6;
1581 		ip6 = NULL;
1582 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
1583 #ifdef VIMAGE
1584 			if (tpr->pr_flags & PR_VNET) {
1585 				descend = 0;
1586 				continue;
1587 			}
1588 #endif
1589 			if (prison_restrict_ip6(tpr, NULL)) {
1590 				redo_ip6 = 1;
1591 				descend = 0;
1592 			}
1593 		}
1594 	}
1595 #endif
1596 	if (gotslevel) {
1597 		pr->pr_securelevel = slevel;
1598 		/* Set all child jails to be at least this level. */
1599 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend)
1600 			if (tpr->pr_securelevel < slevel)
1601 				tpr->pr_securelevel = slevel;
1602 	}
1603 	if (gotchildmax) {
1604 		pr->pr_childmax = childmax;
1605 		/* Set all child jails to under this limit. */
1606 		FOREACH_PRISON_DESCENDANT_LOCKED_LEVEL(pr, tpr, descend, level)
1607 			if (tpr->pr_childmax > childmax - level)
1608 				tpr->pr_childmax = childmax > level
1609 				    ? childmax - level : 0;
1610 	}
1611 	if (gotenforce) {
1612 		pr->pr_enforce_statfs = enforce;
1613 		/* Pass this restriction on to the children. */
1614 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend)
1615 			if (tpr->pr_enforce_statfs < enforce)
1616 				tpr->pr_enforce_statfs = enforce;
1617 	}
1618 	if (gotrsnum) {
1619 		pr->pr_devfs_rsnum = rsnum;
1620 		/* Pass this restriction on to the children. */
1621 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend)
1622 			tpr->pr_devfs_rsnum = rsnum;
1623 	}
1624 	if (namelc != NULL) {
1625 		if (ppr == &prison0)
1626 			strlcpy(pr->pr_name, namelc, sizeof(pr->pr_name));
1627 		else
1628 			snprintf(pr->pr_name, sizeof(pr->pr_name), "%s.%s",
1629 			    ppr->pr_name, namelc);
1630 		/* Change this component of child names. */
1631 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
1632 			bcopy(tpr->pr_name + onamelen, tpr->pr_name + namelen,
1633 			    strlen(tpr->pr_name + onamelen) + 1);
1634 			bcopy(pr->pr_name, tpr->pr_name, namelen);
1635 		}
1636 	}
1637 	if (path != NULL) {
1638 		/* Try to keep a real-rooted full pathname. */
1639 		strlcpy(pr->pr_path, path, sizeof(pr->pr_path));
1640 		pr->pr_root = root;
1641 	}
1642 	if (PR_HOST & ch_flags & ~pr_flags) {
1643 		if (pr->pr_flags & PR_HOST) {
1644 			/*
1645 			 * Copy the parent's host info.  As with pr_ip4 above,
1646 			 * the lack of a lock on the parent is not a problem;
1647 			 * it is always set with allprison_lock at least
1648 			 * shared, and is held exclusively here.
1649 			 */
1650 			strlcpy(pr->pr_hostname, pr->pr_parent->pr_hostname,
1651 			    sizeof(pr->pr_hostname));
1652 			strlcpy(pr->pr_domainname, pr->pr_parent->pr_domainname,
1653 			    sizeof(pr->pr_domainname));
1654 			strlcpy(pr->pr_hostuuid, pr->pr_parent->pr_hostuuid,
1655 			    sizeof(pr->pr_hostuuid));
1656 			pr->pr_hostid = pr->pr_parent->pr_hostid;
1657 		}
1658 	} else if (host != NULL || domain != NULL || uuid != NULL || gothid) {
1659 		/* Set this prison, and any descendants without PR_HOST. */
1660 		if (host != NULL)
1661 			strlcpy(pr->pr_hostname, host, sizeof(pr->pr_hostname));
1662 		if (domain != NULL)
1663 			strlcpy(pr->pr_domainname, domain,
1664 			    sizeof(pr->pr_domainname));
1665 		if (uuid != NULL)
1666 			strlcpy(pr->pr_hostuuid, uuid, sizeof(pr->pr_hostuuid));
1667 		if (gothid)
1668 			pr->pr_hostid = hid;
1669 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
1670 			if (tpr->pr_flags & PR_HOST)
1671 				descend = 0;
1672 			else {
1673 				if (host != NULL)
1674 					strlcpy(tpr->pr_hostname,
1675 					    pr->pr_hostname,
1676 					    sizeof(tpr->pr_hostname));
1677 				if (domain != NULL)
1678 					strlcpy(tpr->pr_domainname,
1679 					    pr->pr_domainname,
1680 					    sizeof(tpr->pr_domainname));
1681 				if (uuid != NULL)
1682 					strlcpy(tpr->pr_hostuuid,
1683 					    pr->pr_hostuuid,
1684 					    sizeof(tpr->pr_hostuuid));
1685 				if (gothid)
1686 					tpr->pr_hostid = hid;
1687 			}
1688 		}
1689 	}
1690 	if ((tallow = ch_allow & ~pr_allow)) {
1691 		/* Clear allow bits in all children. */
1692 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend)
1693 			tpr->pr_allow &= ~tallow;
1694 	}
1695 	pr->pr_allow = (pr->pr_allow & ~ch_allow) | pr_allow;
1696 	/*
1697 	 * Persistent prisons get an extra reference, and prisons losing their
1698 	 * persist flag lose that reference.  Only do this for existing prisons
1699 	 * for now, so new ones will remain unseen until after the module
1700 	 * handlers have completed.
1701 	 */
1702 	born = pr->pr_uref == 0;
1703 	if (!created && (ch_flags & PR_PERSIST & (pr_flags ^ pr->pr_flags))) {
1704 		if (pr_flags & PR_PERSIST) {
1705 			pr->pr_ref++;
1706 			pr->pr_uref++;
1707 		} else {
1708 			pr->pr_ref--;
1709 			pr->pr_uref--;
1710 		}
1711 	}
1712 	pr->pr_flags = (pr->pr_flags & ~ch_flags) | pr_flags;
1713 	mtx_unlock(&pr->pr_mtx);
1714 
1715 #ifdef RACCT
1716 	if (racct_enable && created)
1717 		prison_racct_attach(pr);
1718 #endif
1719 
1720 	/* Locks may have prevented a complete restriction of child IP
1721 	 * addresses.  If so, allocate some more memory and try again.
1722 	 */
1723 #ifdef INET
1724 	while (redo_ip4) {
1725 		ip4s = pr->pr_ip4s;
1726 		ip4 = malloc(ip4s * sizeof(*ip4), M_PRISON, M_WAITOK);
1727 		mtx_lock(&pr->pr_mtx);
1728 		redo_ip4 = 0;
1729 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
1730 #ifdef VIMAGE
1731 			if (tpr->pr_flags & PR_VNET) {
1732 				descend = 0;
1733 				continue;
1734 			}
1735 #endif
1736 			if (prison_restrict_ip4(tpr, ip4)) {
1737 				if (ip4 != NULL)
1738 					ip4 = NULL;
1739 				else
1740 					redo_ip4 = 1;
1741 			}
1742 		}
1743 		mtx_unlock(&pr->pr_mtx);
1744 	}
1745 #endif
1746 #ifdef INET6
1747 	while (redo_ip6) {
1748 		ip6s = pr->pr_ip6s;
1749 		ip6 = malloc(ip6s * sizeof(*ip6), M_PRISON, M_WAITOK);
1750 		mtx_lock(&pr->pr_mtx);
1751 		redo_ip6 = 0;
1752 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
1753 #ifdef VIMAGE
1754 			if (tpr->pr_flags & PR_VNET) {
1755 				descend = 0;
1756 				continue;
1757 			}
1758 #endif
1759 			if (prison_restrict_ip6(tpr, ip6)) {
1760 				if (ip6 != NULL)
1761 					ip6 = NULL;
1762 				else
1763 					redo_ip6 = 1;
1764 			}
1765 		}
1766 		mtx_unlock(&pr->pr_mtx);
1767 	}
1768 #endif
1769 
1770 	/* Let the modules do their work. */
1771 	sx_downgrade(&allprison_lock);
1772 	if (born) {
1773 		error = osd_jail_call(pr, PR_METHOD_CREATE, opts);
1774 		if (error) {
1775 			(void)osd_jail_call(pr, PR_METHOD_REMOVE, NULL);
1776 			prison_deref(pr, created
1777 			    ? PD_LIST_SLOCKED
1778 			    : PD_DEREF | PD_LIST_SLOCKED);
1779 			goto done_errmsg;
1780 		}
1781 	}
1782 	error = osd_jail_call(pr, PR_METHOD_SET, opts);
1783 	if (error) {
1784 		if (born)
1785 			(void)osd_jail_call(pr, PR_METHOD_REMOVE, NULL);
1786 		prison_deref(pr, created
1787 		    ? PD_LIST_SLOCKED
1788 		    : PD_DEREF | PD_LIST_SLOCKED);
1789 		goto done_errmsg;
1790 	}
1791 
1792 	/* Attach this process to the prison if requested. */
1793 	if (flags & JAIL_ATTACH) {
1794 		mtx_lock(&pr->pr_mtx);
1795 		error = do_jail_attach(td, pr);
1796 		if (error) {
1797 			vfs_opterror(opts, "attach failed");
1798 			if (!created)
1799 				prison_deref(pr, PD_DEREF);
1800 			goto done_errmsg;
1801 		}
1802 	}
1803 
1804 #ifdef RACCT
1805 	if (racct_enable && !created) {
1806 		if (!(flags & JAIL_ATTACH))
1807 			sx_sunlock(&allprison_lock);
1808 		prison_racct_modify(pr);
1809 		if (!(flags & JAIL_ATTACH))
1810 			sx_slock(&allprison_lock);
1811 	}
1812 #endif
1813 
1814 	td->td_retval[0] = pr->pr_id;
1815 
1816 	/*
1817 	 * Now that it is all there, drop the temporary reference from existing
1818 	 * prisons.  Or add a reference to newly created persistent prisons
1819 	 * (which was not done earlier so that the prison would not be publicly
1820 	 * visible).
1821 	 */
1822 	if (!created) {
1823 		prison_deref(pr, (flags & JAIL_ATTACH)
1824 		    ? PD_DEREF
1825 		    : PD_DEREF | PD_LIST_SLOCKED);
1826 	} else {
1827 		if (pr_flags & PR_PERSIST) {
1828 			mtx_lock(&pr->pr_mtx);
1829 			pr->pr_ref++;
1830 			pr->pr_uref++;
1831 			mtx_unlock(&pr->pr_mtx);
1832 		}
1833 		if (!(flags & JAIL_ATTACH))
1834 			sx_sunlock(&allprison_lock);
1835 	}
1836 
1837 	goto done_free;
1838 
1839  done_deref_locked:
1840 	prison_deref(pr, created
1841 	    ? PD_LOCKED | PD_LIST_XLOCKED
1842 	    : PD_DEREF | PD_LOCKED | PD_LIST_XLOCKED);
1843 	goto done_releroot;
1844  done_unlock_list:
1845 	sx_xunlock(&allprison_lock);
1846  done_releroot:
1847 	if (root != NULL)
1848 		vrele(root);
1849  done_errmsg:
1850 	if (error) {
1851 		if (vfs_getopt(opts, "errmsg", (void **)&errmsg,
1852 		    &errmsg_len) == 0 && errmsg_len > 0) {
1853 			errmsg_pos = 2 * vfs_getopt_pos(opts, "errmsg") + 1;
1854 			if (optuio->uio_segflg == UIO_SYSSPACE)
1855 				bcopy(errmsg,
1856 				    optuio->uio_iov[errmsg_pos].iov_base,
1857 				    errmsg_len);
1858 			else
1859 				copyout(errmsg,
1860 				    optuio->uio_iov[errmsg_pos].iov_base,
1861 				    errmsg_len);
1862 		}
1863 	}
1864  done_free:
1865 #ifdef INET
1866 	free(ip4, M_PRISON);
1867 #endif
1868 #ifdef INET6
1869 	free(ip6, M_PRISON);
1870 #endif
1871 	if (g_path != NULL)
1872 		free(g_path, M_TEMP);
1873 	vfs_freeopts(opts);
1874 	return (error);
1875 }
1876 
1877 /*
1878  * struct jail_get_args {
1879  *	struct iovec *iovp;
1880  *	unsigned int iovcnt;
1881  *	int flags;
1882  * };
1883  */
1884 int
1885 sys_jail_get(struct thread *td, struct jail_get_args *uap)
1886 {
1887 	struct uio *auio;
1888 	int error;
1889 
1890 	/* Check that we have an even number of iovecs. */
1891 	if (uap->iovcnt & 1)
1892 		return (EINVAL);
1893 
1894 	error = copyinuio(uap->iovp, uap->iovcnt, &auio);
1895 	if (error)
1896 		return (error);
1897 	error = kern_jail_get(td, auio, uap->flags);
1898 	if (error == 0)
1899 		error = copyout(auio->uio_iov, uap->iovp,
1900 		    uap->iovcnt * sizeof (struct iovec));
1901 	free(auio, M_IOV);
1902 	return (error);
1903 }
1904 
1905 int
1906 kern_jail_get(struct thread *td, struct uio *optuio, int flags)
1907 {
1908 	struct bool_flags *bf;
1909 	struct jailsys_flags *jsf;
1910 	struct prison *pr, *mypr;
1911 	struct vfsopt *opt;
1912 	struct vfsoptlist *opts;
1913 	char *errmsg, *name;
1914 	int error, errmsg_len, errmsg_pos, i, jid, len, locked, pos;
1915 	unsigned f;
1916 
1917 	if (flags & ~JAIL_GET_MASK)
1918 		return (EINVAL);
1919 
1920 	/* Get the parameter list. */
1921 	error = vfs_buildopts(optuio, &opts);
1922 	if (error)
1923 		return (error);
1924 	errmsg_pos = vfs_getopt_pos(opts, "errmsg");
1925 	mypr = td->td_ucred->cr_prison;
1926 
1927 	/*
1928 	 * Find the prison specified by one of: lastjid, jid, name.
1929 	 */
1930 	sx_slock(&allprison_lock);
1931 	error = vfs_copyopt(opts, "lastjid", &jid, sizeof(jid));
1932 	if (error == 0) {
1933 		TAILQ_FOREACH(pr, &allprison, pr_list) {
1934 			if (pr->pr_id > jid && prison_ischild(mypr, pr)) {
1935 				mtx_lock(&pr->pr_mtx);
1936 				if (pr->pr_ref > 0 &&
1937 				    (pr->pr_uref > 0 || (flags & JAIL_DYING)))
1938 					break;
1939 				mtx_unlock(&pr->pr_mtx);
1940 			}
1941 		}
1942 		if (pr != NULL)
1943 			goto found_prison;
1944 		error = ENOENT;
1945 		vfs_opterror(opts, "no jail after %d", jid);
1946 		goto done_unlock_list;
1947 	} else if (error != ENOENT)
1948 		goto done_unlock_list;
1949 
1950 	error = vfs_copyopt(opts, "jid", &jid, sizeof(jid));
1951 	if (error == 0) {
1952 		if (jid != 0) {
1953 			pr = prison_find_child(mypr, jid);
1954 			if (pr != NULL) {
1955 				if (pr->pr_uref == 0 && !(flags & JAIL_DYING)) {
1956 					mtx_unlock(&pr->pr_mtx);
1957 					error = ENOENT;
1958 					vfs_opterror(opts, "jail %d is dying",
1959 					    jid);
1960 					goto done_unlock_list;
1961 				}
1962 				goto found_prison;
1963 			}
1964 			error = ENOENT;
1965 			vfs_opterror(opts, "jail %d not found", jid);
1966 			goto done_unlock_list;
1967 		}
1968 	} else if (error != ENOENT)
1969 		goto done_unlock_list;
1970 
1971 	error = vfs_getopt(opts, "name", (void **)&name, &len);
1972 	if (error == 0) {
1973 		if (len == 0 || name[len - 1] != '\0') {
1974 			error = EINVAL;
1975 			goto done_unlock_list;
1976 		}
1977 		pr = prison_find_name(mypr, name);
1978 		if (pr != NULL) {
1979 			if (pr->pr_uref == 0 && !(flags & JAIL_DYING)) {
1980 				mtx_unlock(&pr->pr_mtx);
1981 				error = ENOENT;
1982 				vfs_opterror(opts, "jail \"%s\" is dying",
1983 				    name);
1984 				goto done_unlock_list;
1985 			}
1986 			goto found_prison;
1987 		}
1988 		error = ENOENT;
1989 		vfs_opterror(opts, "jail \"%s\" not found", name);
1990 		goto done_unlock_list;
1991 	} else if (error != ENOENT)
1992 		goto done_unlock_list;
1993 
1994 	vfs_opterror(opts, "no jail specified");
1995 	error = ENOENT;
1996 	goto done_unlock_list;
1997 
1998  found_prison:
1999 	/* Get the parameters of the prison. */
2000 	pr->pr_ref++;
2001 	locked = PD_LOCKED;
2002 	td->td_retval[0] = pr->pr_id;
2003 	error = vfs_setopt(opts, "jid", &pr->pr_id, sizeof(pr->pr_id));
2004 	if (error != 0 && error != ENOENT)
2005 		goto done_deref;
2006 	i = (pr->pr_parent == mypr) ? 0 : pr->pr_parent->pr_id;
2007 	error = vfs_setopt(opts, "parent", &i, sizeof(i));
2008 	if (error != 0 && error != ENOENT)
2009 		goto done_deref;
2010 	error = vfs_setopts(opts, "name", prison_name(mypr, pr));
2011 	if (error != 0 && error != ENOENT)
2012 		goto done_deref;
2013 	error = vfs_setopt(opts, "cpuset.id", &pr->pr_cpuset->cs_id,
2014 	    sizeof(pr->pr_cpuset->cs_id));
2015 	if (error != 0 && error != ENOENT)
2016 		goto done_deref;
2017 	error = vfs_setopts(opts, "path", prison_path(mypr, pr));
2018 	if (error != 0 && error != ENOENT)
2019 		goto done_deref;
2020 #ifdef INET
2021 	error = vfs_setopt_part(opts, "ip4.addr", pr->pr_ip4,
2022 	    pr->pr_ip4s * sizeof(*pr->pr_ip4));
2023 	if (error != 0 && error != ENOENT)
2024 		goto done_deref;
2025 #endif
2026 #ifdef INET6
2027 	error = vfs_setopt_part(opts, "ip6.addr", pr->pr_ip6,
2028 	    pr->pr_ip6s * sizeof(*pr->pr_ip6));
2029 	if (error != 0 && error != ENOENT)
2030 		goto done_deref;
2031 #endif
2032 	error = vfs_setopt(opts, "securelevel", &pr->pr_securelevel,
2033 	    sizeof(pr->pr_securelevel));
2034 	if (error != 0 && error != ENOENT)
2035 		goto done_deref;
2036 	error = vfs_setopt(opts, "children.cur", &pr->pr_childcount,
2037 	    sizeof(pr->pr_childcount));
2038 	if (error != 0 && error != ENOENT)
2039 		goto done_deref;
2040 	error = vfs_setopt(opts, "children.max", &pr->pr_childmax,
2041 	    sizeof(pr->pr_childmax));
2042 	if (error != 0 && error != ENOENT)
2043 		goto done_deref;
2044 	error = vfs_setopts(opts, "host.hostname", pr->pr_hostname);
2045 	if (error != 0 && error != ENOENT)
2046 		goto done_deref;
2047 	error = vfs_setopts(opts, "host.domainname", pr->pr_domainname);
2048 	if (error != 0 && error != ENOENT)
2049 		goto done_deref;
2050 	error = vfs_setopts(opts, "host.hostuuid", pr->pr_hostuuid);
2051 	if (error != 0 && error != ENOENT)
2052 		goto done_deref;
2053 #ifdef COMPAT_FREEBSD32
2054 	if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
2055 		uint32_t hid32 = pr->pr_hostid;
2056 
2057 		error = vfs_setopt(opts, "host.hostid", &hid32, sizeof(hid32));
2058 	} else
2059 #endif
2060 	error = vfs_setopt(opts, "host.hostid", &pr->pr_hostid,
2061 	    sizeof(pr->pr_hostid));
2062 	if (error != 0 && error != ENOENT)
2063 		goto done_deref;
2064 	error = vfs_setopt(opts, "enforce_statfs", &pr->pr_enforce_statfs,
2065 	    sizeof(pr->pr_enforce_statfs));
2066 	if (error != 0 && error != ENOENT)
2067 		goto done_deref;
2068 	error = vfs_setopt(opts, "devfs_ruleset", &pr->pr_devfs_rsnum,
2069 	    sizeof(pr->pr_devfs_rsnum));
2070 	if (error != 0 && error != ENOENT)
2071 		goto done_deref;
2072 	for (bf = pr_flag_bool;
2073 	     bf < pr_flag_bool + nitems(pr_flag_bool);
2074 	     bf++) {
2075 		i = (pr->pr_flags & bf->flag) ? 1 : 0;
2076 		error = vfs_setopt(opts, bf->name, &i, sizeof(i));
2077 		if (error != 0 && error != ENOENT)
2078 			goto done_deref;
2079 		i = !i;
2080 		error = vfs_setopt(opts, bf->noname, &i, sizeof(i));
2081 		if (error != 0 && error != ENOENT)
2082 			goto done_deref;
2083 	}
2084 	for (jsf = pr_flag_jailsys;
2085 	     jsf < pr_flag_jailsys + nitems(pr_flag_jailsys);
2086 	     jsf++) {
2087 		f = pr->pr_flags & (jsf->disable | jsf->new);
2088 		i = (f != 0 && f == jsf->disable) ? JAIL_SYS_DISABLE
2089 		    : (f == jsf->new) ? JAIL_SYS_NEW
2090 		    : JAIL_SYS_INHERIT;
2091 		error = vfs_setopt(opts, jsf->name, &i, sizeof(i));
2092 		if (error != 0 && error != ENOENT)
2093 			goto done_deref;
2094 	}
2095 	for (bf = pr_flag_allow;
2096 	     bf < pr_flag_allow + nitems(pr_flag_allow) && bf->flag != 0;
2097 	     bf++) {
2098 		i = (pr->pr_allow & bf->flag) ? 1 : 0;
2099 		error = vfs_setopt(opts, bf->name, &i, sizeof(i));
2100 		if (error != 0 && error != ENOENT)
2101 			goto done_deref;
2102 		i = !i;
2103 		error = vfs_setopt(opts, bf->noname, &i, sizeof(i));
2104 		if (error != 0 && error != ENOENT)
2105 			goto done_deref;
2106 	}
2107 	i = (pr->pr_uref == 0);
2108 	error = vfs_setopt(opts, "dying", &i, sizeof(i));
2109 	if (error != 0 && error != ENOENT)
2110 		goto done_deref;
2111 	i = !i;
2112 	error = vfs_setopt(opts, "nodying", &i, sizeof(i));
2113 	if (error != 0 && error != ENOENT)
2114 		goto done_deref;
2115 	error = vfs_setopt(opts, "osreldate", &pr->pr_osreldate,
2116 	    sizeof(pr->pr_osreldate));
2117 	if (error != 0 && error != ENOENT)
2118 		goto done_deref;
2119 	error = vfs_setopts(opts, "osrelease", pr->pr_osrelease);
2120 	if (error != 0 && error != ENOENT)
2121 		goto done_deref;
2122 
2123 	/* Get the module parameters. */
2124 	mtx_unlock(&pr->pr_mtx);
2125 	locked = 0;
2126 	error = osd_jail_call(pr, PR_METHOD_GET, opts);
2127 	if (error)
2128 		goto done_deref;
2129 	prison_deref(pr, PD_DEREF | PD_LIST_SLOCKED);
2130 
2131 	/* By now, all parameters should have been noted. */
2132 	TAILQ_FOREACH(opt, opts, link) {
2133 		if (!opt->seen && strcmp(opt->name, "errmsg")) {
2134 			error = EINVAL;
2135 			vfs_opterror(opts, "unknown parameter: %s", opt->name);
2136 			goto done_errmsg;
2137 		}
2138 	}
2139 
2140 	/* Write the fetched parameters back to userspace. */
2141 	error = 0;
2142 	TAILQ_FOREACH(opt, opts, link) {
2143 		if (opt->pos >= 0 && opt->pos != errmsg_pos) {
2144 			pos = 2 * opt->pos + 1;
2145 			optuio->uio_iov[pos].iov_len = opt->len;
2146 			if (opt->value != NULL) {
2147 				if (optuio->uio_segflg == UIO_SYSSPACE) {
2148 					bcopy(opt->value,
2149 					    optuio->uio_iov[pos].iov_base,
2150 					    opt->len);
2151 				} else {
2152 					error = copyout(opt->value,
2153 					    optuio->uio_iov[pos].iov_base,
2154 					    opt->len);
2155 					if (error)
2156 						break;
2157 				}
2158 			}
2159 		}
2160 	}
2161 	goto done_errmsg;
2162 
2163  done_deref:
2164 	prison_deref(pr, locked | PD_DEREF | PD_LIST_SLOCKED);
2165 	goto done_errmsg;
2166 
2167  done_unlock_list:
2168 	sx_sunlock(&allprison_lock);
2169  done_errmsg:
2170 	if (error && errmsg_pos >= 0) {
2171 		vfs_getopt(opts, "errmsg", (void **)&errmsg, &errmsg_len);
2172 		errmsg_pos = 2 * errmsg_pos + 1;
2173 		if (errmsg_len > 0) {
2174 			if (optuio->uio_segflg == UIO_SYSSPACE)
2175 				bcopy(errmsg,
2176 				    optuio->uio_iov[errmsg_pos].iov_base,
2177 				    errmsg_len);
2178 			else
2179 				copyout(errmsg,
2180 				    optuio->uio_iov[errmsg_pos].iov_base,
2181 				    errmsg_len);
2182 		}
2183 	}
2184 	vfs_freeopts(opts);
2185 	return (error);
2186 }
2187 
2188 /*
2189  * struct jail_remove_args {
2190  *	int jid;
2191  * };
2192  */
2193 int
2194 sys_jail_remove(struct thread *td, struct jail_remove_args *uap)
2195 {
2196 	struct prison *pr, *cpr, *lpr, *tpr;
2197 	int descend, error;
2198 
2199 	error = priv_check(td, PRIV_JAIL_REMOVE);
2200 	if (error)
2201 		return (error);
2202 
2203 	sx_xlock(&allprison_lock);
2204 	pr = prison_find_child(td->td_ucred->cr_prison, uap->jid);
2205 	if (pr == NULL) {
2206 		sx_xunlock(&allprison_lock);
2207 		return (EINVAL);
2208 	}
2209 
2210 	/* Remove all descendants of this prison, then remove this prison. */
2211 	pr->pr_ref++;
2212 	if (!LIST_EMPTY(&pr->pr_children)) {
2213 		mtx_unlock(&pr->pr_mtx);
2214 		lpr = NULL;
2215 		FOREACH_PRISON_DESCENDANT(pr, cpr, descend) {
2216 			mtx_lock(&cpr->pr_mtx);
2217 			if (cpr->pr_ref > 0) {
2218 				tpr = cpr;
2219 				cpr->pr_ref++;
2220 			} else {
2221 				/* Already removed - do not do it again. */
2222 				tpr = NULL;
2223 			}
2224 			mtx_unlock(&cpr->pr_mtx);
2225 			if (lpr != NULL) {
2226 				mtx_lock(&lpr->pr_mtx);
2227 				prison_remove_one(lpr);
2228 				sx_xlock(&allprison_lock);
2229 			}
2230 			lpr = tpr;
2231 		}
2232 		if (lpr != NULL) {
2233 			mtx_lock(&lpr->pr_mtx);
2234 			prison_remove_one(lpr);
2235 			sx_xlock(&allprison_lock);
2236 		}
2237 		mtx_lock(&pr->pr_mtx);
2238 	}
2239 	prison_remove_one(pr);
2240 	return (0);
2241 }
2242 
2243 static void
2244 prison_remove_one(struct prison *pr)
2245 {
2246 	struct proc *p;
2247 	int deuref;
2248 
2249 	/* If the prison was persistent, it is not anymore. */
2250 	deuref = 0;
2251 	if (pr->pr_flags & PR_PERSIST) {
2252 		pr->pr_ref--;
2253 		deuref = PD_DEUREF;
2254 		pr->pr_flags &= ~PR_PERSIST;
2255 	}
2256 
2257 	/*
2258 	 * jail_remove added a reference.  If that's the only one, remove
2259 	 * the prison now.
2260 	 */
2261 	KASSERT(pr->pr_ref > 0,
2262 	    ("prison_remove_one removing a dead prison (jid=%d)", pr->pr_id));
2263 	if (pr->pr_ref == 1) {
2264 		prison_deref(pr,
2265 		    deuref | PD_DEREF | PD_LOCKED | PD_LIST_XLOCKED);
2266 		return;
2267 	}
2268 
2269 	mtx_unlock(&pr->pr_mtx);
2270 	sx_xunlock(&allprison_lock);
2271 	/*
2272 	 * Kill all processes unfortunate enough to be attached to this prison.
2273 	 */
2274 	sx_slock(&allproc_lock);
2275 	FOREACH_PROC_IN_SYSTEM(p) {
2276 		PROC_LOCK(p);
2277 		if (p->p_state != PRS_NEW && p->p_ucred &&
2278 		    p->p_ucred->cr_prison == pr)
2279 			kern_psignal(p, SIGKILL);
2280 		PROC_UNLOCK(p);
2281 	}
2282 	sx_sunlock(&allproc_lock);
2283 	/* Remove the temporary reference added by jail_remove. */
2284 	prison_deref(pr, deuref | PD_DEREF);
2285 }
2286 
2287 /*
2288  * struct jail_attach_args {
2289  *	int jid;
2290  * };
2291  */
2292 int
2293 sys_jail_attach(struct thread *td, struct jail_attach_args *uap)
2294 {
2295 	struct prison *pr;
2296 	int error;
2297 
2298 	error = priv_check(td, PRIV_JAIL_ATTACH);
2299 	if (error)
2300 		return (error);
2301 
2302 	/*
2303 	 * Start with exclusive hold on allprison_lock to ensure that a possible
2304 	 * PR_METHOD_REMOVE call isn't concurrent with jail_set or jail_remove.
2305 	 * But then immediately downgrade it since we don't need to stop
2306 	 * readers.
2307 	 */
2308 	sx_xlock(&allprison_lock);
2309 	sx_downgrade(&allprison_lock);
2310 	pr = prison_find_child(td->td_ucred->cr_prison, uap->jid);
2311 	if (pr == NULL) {
2312 		sx_sunlock(&allprison_lock);
2313 		return (EINVAL);
2314 	}
2315 
2316 	/*
2317 	 * Do not allow a process to attach to a prison that is not
2318 	 * considered to be "alive".
2319 	 */
2320 	if (pr->pr_uref == 0) {
2321 		mtx_unlock(&pr->pr_mtx);
2322 		sx_sunlock(&allprison_lock);
2323 		return (EINVAL);
2324 	}
2325 
2326 	return (do_jail_attach(td, pr));
2327 }
2328 
2329 static int
2330 do_jail_attach(struct thread *td, struct prison *pr)
2331 {
2332 	struct proc *p;
2333 	struct ucred *newcred, *oldcred;
2334 	int error;
2335 
2336 	/*
2337 	 * XXX: Note that there is a slight race here if two threads
2338 	 * in the same privileged process attempt to attach to two
2339 	 * different jails at the same time.  It is important for
2340 	 * user processes not to do this, or they might end up with
2341 	 * a process root from one prison, but attached to the jail
2342 	 * of another.
2343 	 */
2344 	pr->pr_ref++;
2345 	pr->pr_uref++;
2346 	mtx_unlock(&pr->pr_mtx);
2347 
2348 	/* Let modules do whatever they need to prepare for attaching. */
2349 	error = osd_jail_call(pr, PR_METHOD_ATTACH, td);
2350 	if (error) {
2351 		prison_deref(pr, PD_DEREF | PD_DEUREF | PD_LIST_SLOCKED);
2352 		return (error);
2353 	}
2354 	sx_sunlock(&allprison_lock);
2355 
2356 	/*
2357 	 * Reparent the newly attached process to this jail.
2358 	 */
2359 	p = td->td_proc;
2360 	error = cpuset_setproc_update_set(p, pr->pr_cpuset);
2361 	if (error)
2362 		goto e_revert_osd;
2363 
2364 	vn_lock(pr->pr_root, LK_EXCLUSIVE | LK_RETRY);
2365 	if ((error = change_dir(pr->pr_root, td)) != 0)
2366 		goto e_unlock;
2367 #ifdef MAC
2368 	if ((error = mac_vnode_check_chroot(td->td_ucred, pr->pr_root)))
2369 		goto e_unlock;
2370 #endif
2371 	VOP_UNLOCK(pr->pr_root);
2372 	if ((error = pwd_chroot(td, pr->pr_root)))
2373 		goto e_revert_osd;
2374 
2375 	newcred = crget();
2376 	PROC_LOCK(p);
2377 	oldcred = crcopysafe(p, newcred);
2378 	newcred->cr_prison = pr;
2379 	proc_set_cred(p, newcred);
2380 	setsugid(p);
2381 #ifdef RACCT
2382 	racct_proc_ucred_changed(p, oldcred, newcred);
2383 	crhold(newcred);
2384 #endif
2385 	PROC_UNLOCK(p);
2386 #ifdef RCTL
2387 	rctl_proc_ucred_changed(p, newcred);
2388 	crfree(newcred);
2389 #endif
2390 	prison_deref(oldcred->cr_prison, PD_DEREF | PD_DEUREF);
2391 	crfree(oldcred);
2392 	return (0);
2393 
2394  e_unlock:
2395 	VOP_UNLOCK(pr->pr_root);
2396  e_revert_osd:
2397 	/* Tell modules this thread is still in its old jail after all. */
2398 	(void)osd_jail_call(td->td_ucred->cr_prison, PR_METHOD_ATTACH, td);
2399 	prison_deref(pr, PD_DEREF | PD_DEUREF);
2400 	return (error);
2401 }
2402 
2403 /*
2404  * Returns a locked prison instance, or NULL on failure.
2405  */
2406 struct prison *
2407 prison_find(int prid)
2408 {
2409 	struct prison *pr;
2410 
2411 	sx_assert(&allprison_lock, SX_LOCKED);
2412 	TAILQ_FOREACH(pr, &allprison, pr_list) {
2413 		if (pr->pr_id == prid) {
2414 			mtx_lock(&pr->pr_mtx);
2415 			if (pr->pr_ref > 0)
2416 				return (pr);
2417 			mtx_unlock(&pr->pr_mtx);
2418 		}
2419 	}
2420 	return (NULL);
2421 }
2422 
2423 /*
2424  * Find a prison that is a descendant of mypr.  Returns a locked prison or NULL.
2425  */
2426 struct prison *
2427 prison_find_child(struct prison *mypr, int prid)
2428 {
2429 	struct prison *pr;
2430 	int descend;
2431 
2432 	sx_assert(&allprison_lock, SX_LOCKED);
2433 	FOREACH_PRISON_DESCENDANT(mypr, pr, descend) {
2434 		if (pr->pr_id == prid) {
2435 			mtx_lock(&pr->pr_mtx);
2436 			if (pr->pr_ref > 0)
2437 				return (pr);
2438 			mtx_unlock(&pr->pr_mtx);
2439 		}
2440 	}
2441 	return (NULL);
2442 }
2443 
2444 /*
2445  * Look for the name relative to mypr.  Returns a locked prison or NULL.
2446  */
2447 struct prison *
2448 prison_find_name(struct prison *mypr, const char *name)
2449 {
2450 	struct prison *pr, *deadpr;
2451 	size_t mylen;
2452 	int descend;
2453 
2454 	sx_assert(&allprison_lock, SX_LOCKED);
2455 	mylen = (mypr == &prison0) ? 0 : strlen(mypr->pr_name) + 1;
2456  again:
2457 	deadpr = NULL;
2458 	FOREACH_PRISON_DESCENDANT(mypr, pr, descend) {
2459 		if (!strcmp(pr->pr_name + mylen, name)) {
2460 			mtx_lock(&pr->pr_mtx);
2461 			if (pr->pr_ref > 0) {
2462 				if (pr->pr_uref > 0)
2463 					return (pr);
2464 				deadpr = pr;
2465 			}
2466 			mtx_unlock(&pr->pr_mtx);
2467 		}
2468 	}
2469 	/* There was no valid prison - perhaps there was a dying one. */
2470 	if (deadpr != NULL) {
2471 		mtx_lock(&deadpr->pr_mtx);
2472 		if (deadpr->pr_ref == 0) {
2473 			mtx_unlock(&deadpr->pr_mtx);
2474 			goto again;
2475 		}
2476 	}
2477 	return (deadpr);
2478 }
2479 
2480 /*
2481  * See if a prison has the specific flag set.
2482  */
2483 int
2484 prison_flag(struct ucred *cred, unsigned flag)
2485 {
2486 
2487 	/* This is an atomic read, so no locking is necessary. */
2488 	return (cred->cr_prison->pr_flags & flag);
2489 }
2490 
2491 int
2492 prison_allow(struct ucred *cred, unsigned flag)
2493 {
2494 
2495 	/* This is an atomic read, so no locking is necessary. */
2496 	return (cred->cr_prison->pr_allow & flag);
2497 }
2498 
2499 /*
2500  * Remove a prison reference.  If that was the last reference, remove the
2501  * prison itself - but not in this context in case there are locks held.
2502  */
2503 void
2504 prison_free_locked(struct prison *pr)
2505 {
2506 	int ref;
2507 
2508 	mtx_assert(&pr->pr_mtx, MA_OWNED);
2509 	ref = --pr->pr_ref;
2510 	mtx_unlock(&pr->pr_mtx);
2511 	if (ref == 0)
2512 		taskqueue_enqueue(taskqueue_thread, &pr->pr_task);
2513 }
2514 
2515 void
2516 prison_free(struct prison *pr)
2517 {
2518 
2519 	mtx_lock(&pr->pr_mtx);
2520 	prison_free_locked(pr);
2521 }
2522 
2523 /*
2524  * Complete a call to either prison_free or prison_proc_free.
2525  */
2526 static void
2527 prison_complete(void *context, int pending)
2528 {
2529 	struct prison *pr = context;
2530 
2531 	sx_xlock(&allprison_lock);
2532 	mtx_lock(&pr->pr_mtx);
2533 	prison_deref(pr, pr->pr_uref
2534 	    ? PD_DEREF | PD_DEUREF | PD_LOCKED | PD_LIST_XLOCKED
2535 	    : PD_LOCKED | PD_LIST_XLOCKED);
2536 }
2537 
2538 /*
2539  * Remove a prison reference (usually).  This internal version assumes no
2540  * mutexes are held, except perhaps the prison itself.  If there are no more
2541  * references, release and delist the prison.  On completion, the prison lock
2542  * and the allprison lock are both unlocked.
2543  */
2544 static void
2545 prison_deref(struct prison *pr, int flags)
2546 {
2547 	struct prison *ppr, *tpr;
2548 	int ref, lasturef;
2549 
2550 	if (!(flags & PD_LOCKED))
2551 		mtx_lock(&pr->pr_mtx);
2552 	for (;;) {
2553 		if (flags & PD_DEUREF) {
2554 			KASSERT(pr->pr_uref > 0,
2555 			    ("prison_deref PD_DEUREF on a dead prison (jid=%d)",
2556 			     pr->pr_id));
2557 			pr->pr_uref--;
2558 			lasturef = pr->pr_uref == 0;
2559 			if (lasturef)
2560 				pr->pr_ref++;
2561 			KASSERT(prison0.pr_uref != 0, ("prison0 pr_uref=0"));
2562 		} else
2563 			lasturef = 0;
2564 		if (flags & PD_DEREF) {
2565 			KASSERT(pr->pr_ref > 0,
2566 			    ("prison_deref PD_DEREF on a dead prison (jid=%d)",
2567 			     pr->pr_id));
2568 			pr->pr_ref--;
2569 		}
2570 		ref = pr->pr_ref;
2571 		mtx_unlock(&pr->pr_mtx);
2572 
2573 		/*
2574 		 * Tell the modules if the last user reference was removed
2575 		 * (even it sticks around in dying state).
2576 		 */
2577 		if (lasturef) {
2578 			if (!(flags & (PD_LIST_SLOCKED | PD_LIST_XLOCKED))) {
2579 				sx_xlock(&allprison_lock);
2580 				flags |= PD_LIST_XLOCKED;
2581 			}
2582 			(void)osd_jail_call(pr, PR_METHOD_REMOVE, NULL);
2583 			mtx_lock(&pr->pr_mtx);
2584 			ref = --pr->pr_ref;
2585 			mtx_unlock(&pr->pr_mtx);
2586 		}
2587 
2588 		/* If the prison still has references, nothing else to do. */
2589 		if (ref > 0) {
2590 			if (flags & PD_LIST_SLOCKED)
2591 				sx_sunlock(&allprison_lock);
2592 			else if (flags & PD_LIST_XLOCKED)
2593 				sx_xunlock(&allprison_lock);
2594 			return;
2595 		}
2596 
2597 		if (flags & PD_LIST_SLOCKED) {
2598 			if (!sx_try_upgrade(&allprison_lock)) {
2599 				sx_sunlock(&allprison_lock);
2600 				sx_xlock(&allprison_lock);
2601 			}
2602 		} else if (!(flags & PD_LIST_XLOCKED))
2603 			sx_xlock(&allprison_lock);
2604 
2605 		TAILQ_REMOVE(&allprison, pr, pr_list);
2606 		LIST_REMOVE(pr, pr_sibling);
2607 		ppr = pr->pr_parent;
2608 		for (tpr = ppr; tpr != NULL; tpr = tpr->pr_parent)
2609 			tpr->pr_childcount--;
2610 		sx_xunlock(&allprison_lock);
2611 
2612 #ifdef VIMAGE
2613 		if (pr->pr_vnet != ppr->pr_vnet)
2614 			vnet_destroy(pr->pr_vnet);
2615 #endif
2616 		if (pr->pr_root != NULL)
2617 			vrele(pr->pr_root);
2618 		mtx_destroy(&pr->pr_mtx);
2619 #ifdef INET
2620 		free(pr->pr_ip4, M_PRISON);
2621 #endif
2622 #ifdef INET6
2623 		free(pr->pr_ip6, M_PRISON);
2624 #endif
2625 		if (pr->pr_cpuset != NULL)
2626 			cpuset_rel(pr->pr_cpuset);
2627 		osd_jail_exit(pr);
2628 #ifdef RACCT
2629 		if (racct_enable)
2630 			prison_racct_detach(pr);
2631 #endif
2632 		free(pr, M_PRISON);
2633 
2634 		/* Removing a prison frees a reference on its parent. */
2635 		pr = ppr;
2636 		mtx_lock(&pr->pr_mtx);
2637 		flags = PD_DEREF | PD_DEUREF;
2638 	}
2639 }
2640 
2641 void
2642 prison_hold_locked(struct prison *pr)
2643 {
2644 
2645 	mtx_assert(&pr->pr_mtx, MA_OWNED);
2646 	KASSERT(pr->pr_ref > 0,
2647 	    ("Trying to hold dead prison %p (jid=%d).", pr, pr->pr_id));
2648 	pr->pr_ref++;
2649 }
2650 
2651 void
2652 prison_hold(struct prison *pr)
2653 {
2654 
2655 	mtx_lock(&pr->pr_mtx);
2656 	prison_hold_locked(pr);
2657 	mtx_unlock(&pr->pr_mtx);
2658 }
2659 
2660 void
2661 prison_proc_hold(struct prison *pr)
2662 {
2663 
2664 	mtx_lock(&pr->pr_mtx);
2665 	KASSERT(pr->pr_uref > 0,
2666 	    ("Cannot add a process to a non-alive prison (jid=%d)", pr->pr_id));
2667 	pr->pr_uref++;
2668 	mtx_unlock(&pr->pr_mtx);
2669 }
2670 
2671 void
2672 prison_proc_free(struct prison *pr)
2673 {
2674 
2675 	mtx_lock(&pr->pr_mtx);
2676 	KASSERT(pr->pr_uref > 0,
2677 	    ("Trying to kill a process in a dead prison (jid=%d)", pr->pr_id));
2678 	if (pr->pr_uref > 1)
2679 		pr->pr_uref--;
2680 	else {
2681 		/*
2682 		 * Don't remove the last user reference in this context, which
2683 		 * is expected to be a process that is not only locked, but
2684 		 * also half dead.
2685 		 */
2686 		pr->pr_ref++;
2687 		mtx_unlock(&pr->pr_mtx);
2688 		taskqueue_enqueue(taskqueue_thread, &pr->pr_task);
2689 		return;
2690 	}
2691 	mtx_unlock(&pr->pr_mtx);
2692 }
2693 
2694 /*
2695  * Check if a jail supports the given address family.
2696  *
2697  * Returns 0 if not jailed or the address family is supported, EAFNOSUPPORT
2698  * if not.
2699  */
2700 int
2701 prison_check_af(struct ucred *cred, int af)
2702 {
2703 	struct prison *pr;
2704 	int error;
2705 
2706 	KASSERT(cred != NULL, ("%s: cred is NULL", __func__));
2707 
2708 	pr = cred->cr_prison;
2709 #ifdef VIMAGE
2710 	/* Prisons with their own network stack are not limited. */
2711 	if (prison_owns_vnet(cred))
2712 		return (0);
2713 #endif
2714 
2715 	error = 0;
2716 	switch (af)
2717 	{
2718 #ifdef INET
2719 	case AF_INET:
2720 		if (pr->pr_flags & PR_IP4)
2721 		{
2722 			mtx_lock(&pr->pr_mtx);
2723 			if ((pr->pr_flags & PR_IP4) && pr->pr_ip4 == NULL)
2724 				error = EAFNOSUPPORT;
2725 			mtx_unlock(&pr->pr_mtx);
2726 		}
2727 		break;
2728 #endif
2729 #ifdef INET6
2730 	case AF_INET6:
2731 		if (pr->pr_flags & PR_IP6)
2732 		{
2733 			mtx_lock(&pr->pr_mtx);
2734 			if ((pr->pr_flags & PR_IP6) && pr->pr_ip6 == NULL)
2735 				error = EAFNOSUPPORT;
2736 			mtx_unlock(&pr->pr_mtx);
2737 		}
2738 		break;
2739 #endif
2740 	case AF_LOCAL:
2741 	case AF_ROUTE:
2742 		break;
2743 	default:
2744 		if (!(pr->pr_allow & PR_ALLOW_SOCKET_AF))
2745 			error = EAFNOSUPPORT;
2746 	}
2747 	return (error);
2748 }
2749 
2750 /*
2751  * Check if given address belongs to the jail referenced by cred (wrapper to
2752  * prison_check_ip[46]).
2753  *
2754  * Returns 0 if jail doesn't restrict the address family or if address belongs
2755  * to jail, EADDRNOTAVAIL if the address doesn't belong, or EAFNOSUPPORT if
2756  * the jail doesn't allow the address family.  IPv4 Address passed in in NBO.
2757  */
2758 int
2759 prison_if(struct ucred *cred, const struct sockaddr *sa)
2760 {
2761 #ifdef INET
2762 	const struct sockaddr_in *sai;
2763 #endif
2764 #ifdef INET6
2765 	const struct sockaddr_in6 *sai6;
2766 #endif
2767 	int error;
2768 
2769 	KASSERT(cred != NULL, ("%s: cred is NULL", __func__));
2770 	KASSERT(sa != NULL, ("%s: sa is NULL", __func__));
2771 
2772 #ifdef VIMAGE
2773 	if (prison_owns_vnet(cred))
2774 		return (0);
2775 #endif
2776 
2777 	error = 0;
2778 	switch (sa->sa_family)
2779 	{
2780 #ifdef INET
2781 	case AF_INET:
2782 		sai = (const struct sockaddr_in *)sa;
2783 		error = prison_check_ip4(cred, &sai->sin_addr);
2784 		break;
2785 #endif
2786 #ifdef INET6
2787 	case AF_INET6:
2788 		sai6 = (const struct sockaddr_in6 *)sa;
2789 		error = prison_check_ip6(cred, &sai6->sin6_addr);
2790 		break;
2791 #endif
2792 	default:
2793 		if (!(cred->cr_prison->pr_allow & PR_ALLOW_SOCKET_AF))
2794 			error = EAFNOSUPPORT;
2795 	}
2796 	return (error);
2797 }
2798 
2799 /*
2800  * Return 0 if jails permit p1 to frob p2, otherwise ESRCH.
2801  */
2802 int
2803 prison_check(struct ucred *cred1, struct ucred *cred2)
2804 {
2805 
2806 	return ((cred1->cr_prison == cred2->cr_prison ||
2807 	    prison_ischild(cred1->cr_prison, cred2->cr_prison)) ? 0 : ESRCH);
2808 }
2809 
2810 /*
2811  * Return 1 if p2 is a child of p1, otherwise 0.
2812  */
2813 int
2814 prison_ischild(struct prison *pr1, struct prison *pr2)
2815 {
2816 
2817 	for (pr2 = pr2->pr_parent; pr2 != NULL; pr2 = pr2->pr_parent)
2818 		if (pr1 == pr2)
2819 			return (1);
2820 	return (0);
2821 }
2822 
2823 /*
2824  * Return 1 if the passed credential is in a jail and that jail does not
2825  * have its own virtual network stack, otherwise 0.
2826  */
2827 int
2828 jailed_without_vnet(struct ucred *cred)
2829 {
2830 
2831 	if (!jailed(cred))
2832 		return (0);
2833 #ifdef VIMAGE
2834 	if (prison_owns_vnet(cred))
2835 		return (0);
2836 #endif
2837 
2838 	return (1);
2839 }
2840 
2841 /*
2842  * Return the correct hostname (domainname, et al) for the passed credential.
2843  */
2844 void
2845 getcredhostname(struct ucred *cred, char *buf, size_t size)
2846 {
2847 	struct prison *pr;
2848 
2849 	/*
2850 	 * A NULL credential can be used to shortcut to the physical
2851 	 * system's hostname.
2852 	 */
2853 	pr = (cred != NULL) ? cred->cr_prison : &prison0;
2854 	mtx_lock(&pr->pr_mtx);
2855 	strlcpy(buf, pr->pr_hostname, size);
2856 	mtx_unlock(&pr->pr_mtx);
2857 }
2858 
2859 void
2860 getcreddomainname(struct ucred *cred, char *buf, size_t size)
2861 {
2862 
2863 	mtx_lock(&cred->cr_prison->pr_mtx);
2864 	strlcpy(buf, cred->cr_prison->pr_domainname, size);
2865 	mtx_unlock(&cred->cr_prison->pr_mtx);
2866 }
2867 
2868 void
2869 getcredhostuuid(struct ucred *cred, char *buf, size_t size)
2870 {
2871 
2872 	mtx_lock(&cred->cr_prison->pr_mtx);
2873 	strlcpy(buf, cred->cr_prison->pr_hostuuid, size);
2874 	mtx_unlock(&cred->cr_prison->pr_mtx);
2875 }
2876 
2877 void
2878 getcredhostid(struct ucred *cred, unsigned long *hostid)
2879 {
2880 
2881 	mtx_lock(&cred->cr_prison->pr_mtx);
2882 	*hostid = cred->cr_prison->pr_hostid;
2883 	mtx_unlock(&cred->cr_prison->pr_mtx);
2884 }
2885 
2886 #ifdef VIMAGE
2887 /*
2888  * Determine whether the prison represented by cred owns
2889  * its vnet rather than having it inherited.
2890  *
2891  * Returns 1 in case the prison owns the vnet, 0 otherwise.
2892  */
2893 int
2894 prison_owns_vnet(struct ucred *cred)
2895 {
2896 
2897 	/*
2898 	 * vnets cannot be added/removed after jail creation,
2899 	 * so no need to lock here.
2900 	 */
2901 	return (cred->cr_prison->pr_flags & PR_VNET ? 1 : 0);
2902 }
2903 #endif
2904 
2905 /*
2906  * Determine whether the subject represented by cred can "see"
2907  * status of a mount point.
2908  * Returns: 0 for permitted, ENOENT otherwise.
2909  * XXX: This function should be called cr_canseemount() and should be
2910  *      placed in kern_prot.c.
2911  */
2912 int
2913 prison_canseemount(struct ucred *cred, struct mount *mp)
2914 {
2915 	struct prison *pr;
2916 	struct statfs *sp;
2917 	size_t len;
2918 
2919 	pr = cred->cr_prison;
2920 	if (pr->pr_enforce_statfs == 0)
2921 		return (0);
2922 	if (pr->pr_root->v_mount == mp)
2923 		return (0);
2924 	if (pr->pr_enforce_statfs == 2)
2925 		return (ENOENT);
2926 	/*
2927 	 * If jail's chroot directory is set to "/" we should be able to see
2928 	 * all mount-points from inside a jail.
2929 	 * This is ugly check, but this is the only situation when jail's
2930 	 * directory ends with '/'.
2931 	 */
2932 	if (strcmp(pr->pr_path, "/") == 0)
2933 		return (0);
2934 	len = strlen(pr->pr_path);
2935 	sp = &mp->mnt_stat;
2936 	if (strncmp(pr->pr_path, sp->f_mntonname, len) != 0)
2937 		return (ENOENT);
2938 	/*
2939 	 * Be sure that we don't have situation where jail's root directory
2940 	 * is "/some/path" and mount point is "/some/pathpath".
2941 	 */
2942 	if (sp->f_mntonname[len] != '\0' && sp->f_mntonname[len] != '/')
2943 		return (ENOENT);
2944 	return (0);
2945 }
2946 
2947 void
2948 prison_enforce_statfs(struct ucred *cred, struct mount *mp, struct statfs *sp)
2949 {
2950 	char jpath[MAXPATHLEN];
2951 	struct prison *pr;
2952 	size_t len;
2953 
2954 	pr = cred->cr_prison;
2955 	if (pr->pr_enforce_statfs == 0)
2956 		return;
2957 	if (prison_canseemount(cred, mp) != 0) {
2958 		bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
2959 		strlcpy(sp->f_mntonname, "[restricted]",
2960 		    sizeof(sp->f_mntonname));
2961 		return;
2962 	}
2963 	if (pr->pr_root->v_mount == mp) {
2964 		/*
2965 		 * Clear current buffer data, so we are sure nothing from
2966 		 * the valid path left there.
2967 		 */
2968 		bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
2969 		*sp->f_mntonname = '/';
2970 		return;
2971 	}
2972 	/*
2973 	 * If jail's chroot directory is set to "/" we should be able to see
2974 	 * all mount-points from inside a jail.
2975 	 */
2976 	if (strcmp(pr->pr_path, "/") == 0)
2977 		return;
2978 	len = strlen(pr->pr_path);
2979 	strlcpy(jpath, sp->f_mntonname + len, sizeof(jpath));
2980 	/*
2981 	 * Clear current buffer data, so we are sure nothing from
2982 	 * the valid path left there.
2983 	 */
2984 	bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
2985 	if (*jpath == '\0') {
2986 		/* Should never happen. */
2987 		*sp->f_mntonname = '/';
2988 	} else {
2989 		strlcpy(sp->f_mntonname, jpath, sizeof(sp->f_mntonname));
2990 	}
2991 }
2992 
2993 /*
2994  * Check with permission for a specific privilege is granted within jail.  We
2995  * have a specific list of accepted privileges; the rest are denied.
2996  */
2997 int
2998 prison_priv_check(struct ucred *cred, int priv)
2999 {
3000 
3001 	/*
3002 	 * Some policies have custom handlers. This routine should not be
3003 	 * called for them. See priv_check_cred().
3004 	 */
3005 	switch (priv) {
3006 	case PRIV_VFS_GENERATION:
3007 		KASSERT(0, ("prison_priv_check instead of a custom handler "
3008 		    "called for %d\n", priv));
3009 	}
3010 
3011 	if (!jailed(cred))
3012 		return (0);
3013 
3014 #ifdef VIMAGE
3015 	/*
3016 	 * Privileges specific to prisons with a virtual network stack.
3017 	 * There might be a duplicate entry here in case the privilege
3018 	 * is only granted conditionally in the legacy jail case.
3019 	 */
3020 	switch (priv) {
3021 #ifdef notyet
3022 		/*
3023 		 * NFS-specific privileges.
3024 		 */
3025 	case PRIV_NFS_DAEMON:
3026 	case PRIV_NFS_LOCKD:
3027 #endif
3028 		/*
3029 		 * Network stack privileges.
3030 		 */
3031 	case PRIV_NET_BRIDGE:
3032 	case PRIV_NET_GRE:
3033 	case PRIV_NET_BPF:
3034 	case PRIV_NET_RAW:		/* Dup, cond. in legacy jail case. */
3035 	case PRIV_NET_ROUTE:
3036 	case PRIV_NET_TAP:
3037 	case PRIV_NET_SETIFMTU:
3038 	case PRIV_NET_SETIFFLAGS:
3039 	case PRIV_NET_SETIFCAP:
3040 	case PRIV_NET_SETIFDESCR:
3041 	case PRIV_NET_SETIFNAME	:
3042 	case PRIV_NET_SETIFMETRIC:
3043 	case PRIV_NET_SETIFPHYS:
3044 	case PRIV_NET_SETIFMAC:
3045 	case PRIV_NET_SETLANPCP:
3046 	case PRIV_NET_ADDMULTI:
3047 	case PRIV_NET_DELMULTI:
3048 	case PRIV_NET_HWIOCTL:
3049 	case PRIV_NET_SETLLADDR:
3050 	case PRIV_NET_ADDIFGROUP:
3051 	case PRIV_NET_DELIFGROUP:
3052 	case PRIV_NET_IFCREATE:
3053 	case PRIV_NET_IFDESTROY:
3054 	case PRIV_NET_ADDIFADDR:
3055 	case PRIV_NET_DELIFADDR:
3056 	case PRIV_NET_LAGG:
3057 	case PRIV_NET_GIF:
3058 	case PRIV_NET_SETIFVNET:
3059 	case PRIV_NET_SETIFFIB:
3060 
3061 		/*
3062 		 * 802.11-related privileges.
3063 		 */
3064 	case PRIV_NET80211_GETKEY:
3065 #ifdef notyet
3066 	case PRIV_NET80211_MANAGE:		/* XXX-BZ discuss with sam@ */
3067 #endif
3068 
3069 #ifdef notyet
3070 		/*
3071 		 * ATM privileges.
3072 		 */
3073 	case PRIV_NETATM_CFG:
3074 	case PRIV_NETATM_ADD:
3075 	case PRIV_NETATM_DEL:
3076 	case PRIV_NETATM_SET:
3077 
3078 		/*
3079 		 * Bluetooth privileges.
3080 		 */
3081 	case PRIV_NETBLUETOOTH_RAW:
3082 #endif
3083 
3084 		/*
3085 		 * Netgraph and netgraph module privileges.
3086 		 */
3087 	case PRIV_NETGRAPH_CONTROL:
3088 #ifdef notyet
3089 	case PRIV_NETGRAPH_TTY:
3090 #endif
3091 
3092 		/*
3093 		 * IPv4 and IPv6 privileges.
3094 		 */
3095 	case PRIV_NETINET_IPFW:
3096 	case PRIV_NETINET_DIVERT:
3097 	case PRIV_NETINET_PF:
3098 	case PRIV_NETINET_DUMMYNET:
3099 	case PRIV_NETINET_CARP:
3100 	case PRIV_NETINET_MROUTE:
3101 	case PRIV_NETINET_RAW:
3102 	case PRIV_NETINET_ADDRCTRL6:
3103 	case PRIV_NETINET_ND6:
3104 	case PRIV_NETINET_SCOPE6:
3105 	case PRIV_NETINET_ALIFETIME6:
3106 	case PRIV_NETINET_IPSEC:
3107 	case PRIV_NETINET_BINDANY:
3108 
3109 #ifdef notyet
3110 		/*
3111 		 * NCP privileges.
3112 		 */
3113 	case PRIV_NETNCP:
3114 
3115 		/*
3116 		 * SMB privileges.
3117 		 */
3118 	case PRIV_NETSMB:
3119 #endif
3120 
3121 	/*
3122 	 * No default: or deny here.
3123 	 * In case of no permit fall through to next switch().
3124 	 */
3125 		if (cred->cr_prison->pr_flags & PR_VNET)
3126 			return (0);
3127 	}
3128 #endif /* VIMAGE */
3129 
3130 	switch (priv) {
3131 
3132 		/*
3133 		 * Allow ktrace privileges for root in jail.
3134 		 */
3135 	case PRIV_KTRACE:
3136 
3137 #if 0
3138 		/*
3139 		 * Allow jailed processes to configure audit identity and
3140 		 * submit audit records (login, etc).  In the future we may
3141 		 * want to further refine the relationship between audit and
3142 		 * jail.
3143 		 */
3144 	case PRIV_AUDIT_GETAUDIT:
3145 	case PRIV_AUDIT_SETAUDIT:
3146 	case PRIV_AUDIT_SUBMIT:
3147 #endif
3148 
3149 		/*
3150 		 * Allow jailed processes to manipulate process UNIX
3151 		 * credentials in any way they see fit.
3152 		 */
3153 	case PRIV_CRED_SETUID:
3154 	case PRIV_CRED_SETEUID:
3155 	case PRIV_CRED_SETGID:
3156 	case PRIV_CRED_SETEGID:
3157 	case PRIV_CRED_SETGROUPS:
3158 	case PRIV_CRED_SETREUID:
3159 	case PRIV_CRED_SETREGID:
3160 	case PRIV_CRED_SETRESUID:
3161 	case PRIV_CRED_SETRESGID:
3162 
3163 		/*
3164 		 * Jail implements visibility constraints already, so allow
3165 		 * jailed root to override uid/gid-based constraints.
3166 		 */
3167 	case PRIV_SEEOTHERGIDS:
3168 	case PRIV_SEEOTHERUIDS:
3169 
3170 		/*
3171 		 * Jail implements inter-process debugging limits already, so
3172 		 * allow jailed root various debugging privileges.
3173 		 */
3174 	case PRIV_DEBUG_DIFFCRED:
3175 	case PRIV_DEBUG_SUGID:
3176 	case PRIV_DEBUG_UNPRIV:
3177 
3178 		/*
3179 		 * Allow jail to set various resource limits and login
3180 		 * properties, and for now, exceed process resource limits.
3181 		 */
3182 	case PRIV_PROC_LIMIT:
3183 	case PRIV_PROC_SETLOGIN:
3184 	case PRIV_PROC_SETRLIMIT:
3185 
3186 		/*
3187 		 * System V and POSIX IPC privileges are granted in jail.
3188 		 */
3189 	case PRIV_IPC_READ:
3190 	case PRIV_IPC_WRITE:
3191 	case PRIV_IPC_ADMIN:
3192 	case PRIV_IPC_MSGSIZE:
3193 	case PRIV_MQ_ADMIN:
3194 
3195 		/*
3196 		 * Jail operations within a jail work on child jails.
3197 		 */
3198 	case PRIV_JAIL_ATTACH:
3199 	case PRIV_JAIL_SET:
3200 	case PRIV_JAIL_REMOVE:
3201 
3202 		/*
3203 		 * Jail implements its own inter-process limits, so allow
3204 		 * root processes in jail to change scheduling on other
3205 		 * processes in the same jail.  Likewise for signalling.
3206 		 */
3207 	case PRIV_SCHED_DIFFCRED:
3208 	case PRIV_SCHED_CPUSET:
3209 	case PRIV_SIGNAL_DIFFCRED:
3210 	case PRIV_SIGNAL_SUGID:
3211 
3212 		/*
3213 		 * Allow jailed processes to write to sysctls marked as jail
3214 		 * writable.
3215 		 */
3216 	case PRIV_SYSCTL_WRITEJAIL:
3217 
3218 		/*
3219 		 * Allow root in jail to manage a variety of quota
3220 		 * properties.  These should likely be conditional on a
3221 		 * configuration option.
3222 		 */
3223 	case PRIV_VFS_GETQUOTA:
3224 	case PRIV_VFS_SETQUOTA:
3225 
3226 		/*
3227 		 * Since Jail relies on chroot() to implement file system
3228 		 * protections, grant many VFS privileges to root in jail.
3229 		 * Be careful to exclude mount-related and NFS-related
3230 		 * privileges.
3231 		 */
3232 	case PRIV_VFS_READ:
3233 	case PRIV_VFS_WRITE:
3234 	case PRIV_VFS_ADMIN:
3235 	case PRIV_VFS_EXEC:
3236 	case PRIV_VFS_LOOKUP:
3237 	case PRIV_VFS_BLOCKRESERVE:	/* XXXRW: Slightly surprising. */
3238 	case PRIV_VFS_CHFLAGS_DEV:
3239 	case PRIV_VFS_CHOWN:
3240 	case PRIV_VFS_CHROOT:
3241 	case PRIV_VFS_RETAINSUGID:
3242 	case PRIV_VFS_FCHROOT:
3243 	case PRIV_VFS_LINK:
3244 	case PRIV_VFS_SETGID:
3245 	case PRIV_VFS_STAT:
3246 	case PRIV_VFS_STICKYFILE:
3247 
3248 		/*
3249 		 * As in the non-jail case, non-root users are expected to be
3250 		 * able to read kernel/phyiscal memory (provided /dev/[k]mem
3251 		 * exists in the jail and they have permission to access it).
3252 		 */
3253 	case PRIV_KMEM_READ:
3254 		return (0);
3255 
3256 		/*
3257 		 * Depending on the global setting, allow privilege of
3258 		 * setting system flags.
3259 		 */
3260 	case PRIV_VFS_SYSFLAGS:
3261 		if (cred->cr_prison->pr_allow & PR_ALLOW_CHFLAGS)
3262 			return (0);
3263 		else
3264 			return (EPERM);
3265 
3266 		/*
3267 		 * Depending on the global setting, allow privilege of
3268 		 * mounting/unmounting file systems.
3269 		 */
3270 	case PRIV_VFS_MOUNT:
3271 	case PRIV_VFS_UNMOUNT:
3272 	case PRIV_VFS_MOUNT_NONUSER:
3273 	case PRIV_VFS_MOUNT_OWNER:
3274 		if (cred->cr_prison->pr_allow & PR_ALLOW_MOUNT &&
3275 		    cred->cr_prison->pr_enforce_statfs < 2)
3276 			return (0);
3277 		else
3278 			return (EPERM);
3279 
3280 		/*
3281 		 * Conditionnaly allow locking (unlocking) physical pages
3282 		 * in memory.
3283 		 */
3284 	case PRIV_VM_MLOCK:
3285 	case PRIV_VM_MUNLOCK:
3286 		if (cred->cr_prison->pr_allow & PR_ALLOW_MLOCK)
3287 			return (0);
3288 		else
3289 			return (EPERM);
3290 
3291 		/*
3292 		 * Conditionally allow jailed root to bind reserved ports.
3293 		 */
3294 	case PRIV_NETINET_RESERVEDPORT:
3295 		if (cred->cr_prison->pr_allow & PR_ALLOW_RESERVED_PORTS)
3296 			return (0);
3297 		else
3298 			return (EPERM);
3299 
3300 		/*
3301 		 * Allow jailed root to reuse in-use ports.
3302 		 */
3303 	case PRIV_NETINET_REUSEPORT:
3304 		return (0);
3305 
3306 		/*
3307 		 * Allow jailed root to set certain IPv4/6 (option) headers.
3308 		 */
3309 	case PRIV_NETINET_SETHDROPTS:
3310 		return (0);
3311 
3312 		/*
3313 		 * Conditionally allow creating raw sockets in jail.
3314 		 */
3315 	case PRIV_NETINET_RAW:
3316 		if (cred->cr_prison->pr_allow & PR_ALLOW_RAW_SOCKETS)
3317 			return (0);
3318 		else
3319 			return (EPERM);
3320 
3321 		/*
3322 		 * Since jail implements its own visibility limits on netstat
3323 		 * sysctls, allow getcred.  This allows identd to work in
3324 		 * jail.
3325 		 */
3326 	case PRIV_NETINET_GETCRED:
3327 		return (0);
3328 
3329 		/*
3330 		 * Allow jailed root to set loginclass.
3331 		 */
3332 	case PRIV_PROC_SETLOGINCLASS:
3333 		return (0);
3334 
3335 		/*
3336 		 * Do not allow a process inside a jail to read the kernel
3337 		 * message buffer unless explicitly permitted.
3338 		 */
3339 	case PRIV_MSGBUF:
3340 		if (cred->cr_prison->pr_allow & PR_ALLOW_READ_MSGBUF)
3341 			return (0);
3342 		return (EPERM);
3343 
3344 	default:
3345 		/*
3346 		 * In all remaining cases, deny the privilege request.  This
3347 		 * includes almost all network privileges, many system
3348 		 * configuration privileges.
3349 		 */
3350 		return (EPERM);
3351 	}
3352 }
3353 
3354 /*
3355  * Return the part of pr2's name that is relative to pr1, or the whole name
3356  * if it does not directly follow.
3357  */
3358 
3359 char *
3360 prison_name(struct prison *pr1, struct prison *pr2)
3361 {
3362 	char *name;
3363 
3364 	/* Jails see themselves as "0" (if they see themselves at all). */
3365 	if (pr1 == pr2)
3366 		return "0";
3367 	name = pr2->pr_name;
3368 	if (prison_ischild(pr1, pr2)) {
3369 		/*
3370 		 * pr1 isn't locked (and allprison_lock may not be either)
3371 		 * so its length can't be counted on.  But the number of dots
3372 		 * can be counted on - and counted.
3373 		 */
3374 		for (; pr1 != &prison0; pr1 = pr1->pr_parent)
3375 			name = strchr(name, '.') + 1;
3376 	}
3377 	return (name);
3378 }
3379 
3380 /*
3381  * Return the part of pr2's path that is relative to pr1, or the whole path
3382  * if it does not directly follow.
3383  */
3384 static char *
3385 prison_path(struct prison *pr1, struct prison *pr2)
3386 {
3387 	char *path1, *path2;
3388 	int len1;
3389 
3390 	path1 = pr1->pr_path;
3391 	path2 = pr2->pr_path;
3392 	if (!strcmp(path1, "/"))
3393 		return (path2);
3394 	len1 = strlen(path1);
3395 	if (strncmp(path1, path2, len1))
3396 		return (path2);
3397 	if (path2[len1] == '\0')
3398 		return "/";
3399 	if (path2[len1] == '/')
3400 		return (path2 + len1);
3401 	return (path2);
3402 }
3403 
3404 /*
3405  * Jail-related sysctls.
3406  */
3407 static SYSCTL_NODE(_security, OID_AUTO, jail, CTLFLAG_RW, 0,
3408     "Jails");
3409 
3410 static int
3411 sysctl_jail_list(SYSCTL_HANDLER_ARGS)
3412 {
3413 	struct xprison *xp;
3414 	struct prison *pr, *cpr;
3415 #ifdef INET
3416 	struct in_addr *ip4 = NULL;
3417 	int ip4s = 0;
3418 #endif
3419 #ifdef INET6
3420 	struct in6_addr *ip6 = NULL;
3421 	int ip6s = 0;
3422 #endif
3423 	int descend, error;
3424 
3425 	xp = malloc(sizeof(*xp), M_TEMP, M_WAITOK);
3426 	pr = req->td->td_ucred->cr_prison;
3427 	error = 0;
3428 	sx_slock(&allprison_lock);
3429 	FOREACH_PRISON_DESCENDANT(pr, cpr, descend) {
3430 #if defined(INET) || defined(INET6)
3431  again:
3432 #endif
3433 		mtx_lock(&cpr->pr_mtx);
3434 #ifdef INET
3435 		if (cpr->pr_ip4s > 0) {
3436 			if (ip4s < cpr->pr_ip4s) {
3437 				ip4s = cpr->pr_ip4s;
3438 				mtx_unlock(&cpr->pr_mtx);
3439 				ip4 = realloc(ip4, ip4s *
3440 				    sizeof(struct in_addr), M_TEMP, M_WAITOK);
3441 				goto again;
3442 			}
3443 			bcopy(cpr->pr_ip4, ip4,
3444 			    cpr->pr_ip4s * sizeof(struct in_addr));
3445 		}
3446 #endif
3447 #ifdef INET6
3448 		if (cpr->pr_ip6s > 0) {
3449 			if (ip6s < cpr->pr_ip6s) {
3450 				ip6s = cpr->pr_ip6s;
3451 				mtx_unlock(&cpr->pr_mtx);
3452 				ip6 = realloc(ip6, ip6s *
3453 				    sizeof(struct in6_addr), M_TEMP, M_WAITOK);
3454 				goto again;
3455 			}
3456 			bcopy(cpr->pr_ip6, ip6,
3457 			    cpr->pr_ip6s * sizeof(struct in6_addr));
3458 		}
3459 #endif
3460 		if (cpr->pr_ref == 0) {
3461 			mtx_unlock(&cpr->pr_mtx);
3462 			continue;
3463 		}
3464 		bzero(xp, sizeof(*xp));
3465 		xp->pr_version = XPRISON_VERSION;
3466 		xp->pr_id = cpr->pr_id;
3467 		xp->pr_state = cpr->pr_uref > 0
3468 		    ? PRISON_STATE_ALIVE : PRISON_STATE_DYING;
3469 		strlcpy(xp->pr_path, prison_path(pr, cpr), sizeof(xp->pr_path));
3470 		strlcpy(xp->pr_host, cpr->pr_hostname, sizeof(xp->pr_host));
3471 		strlcpy(xp->pr_name, prison_name(pr, cpr), sizeof(xp->pr_name));
3472 #ifdef INET
3473 		xp->pr_ip4s = cpr->pr_ip4s;
3474 #endif
3475 #ifdef INET6
3476 		xp->pr_ip6s = cpr->pr_ip6s;
3477 #endif
3478 		mtx_unlock(&cpr->pr_mtx);
3479 		error = SYSCTL_OUT(req, xp, sizeof(*xp));
3480 		if (error)
3481 			break;
3482 #ifdef INET
3483 		if (xp->pr_ip4s > 0) {
3484 			error = SYSCTL_OUT(req, ip4,
3485 			    xp->pr_ip4s * sizeof(struct in_addr));
3486 			if (error)
3487 				break;
3488 		}
3489 #endif
3490 #ifdef INET6
3491 		if (xp->pr_ip6s > 0) {
3492 			error = SYSCTL_OUT(req, ip6,
3493 			    xp->pr_ip6s * sizeof(struct in6_addr));
3494 			if (error)
3495 				break;
3496 		}
3497 #endif
3498 	}
3499 	sx_sunlock(&allprison_lock);
3500 	free(xp, M_TEMP);
3501 #ifdef INET
3502 	free(ip4, M_TEMP);
3503 #endif
3504 #ifdef INET6
3505 	free(ip6, M_TEMP);
3506 #endif
3507 	return (error);
3508 }
3509 
3510 SYSCTL_OID(_security_jail, OID_AUTO, list,
3511     CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
3512     sysctl_jail_list, "S", "List of active jails");
3513 
3514 static int
3515 sysctl_jail_jailed(SYSCTL_HANDLER_ARGS)
3516 {
3517 	int error, injail;
3518 
3519 	injail = jailed(req->td->td_ucred);
3520 	error = SYSCTL_OUT(req, &injail, sizeof(injail));
3521 
3522 	return (error);
3523 }
3524 
3525 SYSCTL_PROC(_security_jail, OID_AUTO, jailed,
3526     CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
3527     sysctl_jail_jailed, "I", "Process in jail?");
3528 
3529 static int
3530 sysctl_jail_vnet(SYSCTL_HANDLER_ARGS)
3531 {
3532 	int error, havevnet;
3533 #ifdef VIMAGE
3534 	struct ucred *cred = req->td->td_ucred;
3535 
3536 	havevnet = jailed(cred) && prison_owns_vnet(cred);
3537 #else
3538 	havevnet = 0;
3539 #endif
3540 	error = SYSCTL_OUT(req, &havevnet, sizeof(havevnet));
3541 
3542 	return (error);
3543 }
3544 
3545 SYSCTL_PROC(_security_jail, OID_AUTO, vnet,
3546     CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
3547     sysctl_jail_vnet, "I", "Jail owns vnet?");
3548 
3549 #if defined(INET) || defined(INET6)
3550 SYSCTL_UINT(_security_jail, OID_AUTO, jail_max_af_ips, CTLFLAG_RW,
3551     &jail_max_af_ips, 0,
3552     "Number of IP addresses a jail may have at most per address family (deprecated)");
3553 #endif
3554 
3555 /*
3556  * Default parameters for jail(2) compatibility.  For historical reasons,
3557  * the sysctl names have varying similarity to the parameter names.  Prisons
3558  * just see their own parameters, and can't change them.
3559  */
3560 static int
3561 sysctl_jail_default_allow(SYSCTL_HANDLER_ARGS)
3562 {
3563 	struct prison *pr;
3564 	int allow, error, i;
3565 
3566 	pr = req->td->td_ucred->cr_prison;
3567 	allow = (pr == &prison0) ? jail_default_allow : pr->pr_allow;
3568 
3569 	/* Get the current flag value, and convert it to a boolean. */
3570 	i = (allow & arg2) ? 1 : 0;
3571 	if (arg1 != NULL)
3572 		i = !i;
3573 	error = sysctl_handle_int(oidp, &i, 0, req);
3574 	if (error || !req->newptr)
3575 		return (error);
3576 	i = i ? arg2 : 0;
3577 	if (arg1 != NULL)
3578 		i ^= arg2;
3579 	/*
3580 	 * The sysctls don't have CTLFLAGS_PRISON, so assume prison0
3581 	 * for writing.
3582 	 */
3583 	mtx_lock(&prison0.pr_mtx);
3584 	jail_default_allow = (jail_default_allow & ~arg2) | i;
3585 	mtx_unlock(&prison0.pr_mtx);
3586 	return (0);
3587 }
3588 
3589 SYSCTL_PROC(_security_jail, OID_AUTO, set_hostname_allowed,
3590     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
3591     NULL, PR_ALLOW_SET_HOSTNAME, sysctl_jail_default_allow, "I",
3592     "Processes in jail can set their hostnames (deprecated)");
3593 SYSCTL_PROC(_security_jail, OID_AUTO, socket_unixiproute_only,
3594     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
3595     (void *)1, PR_ALLOW_SOCKET_AF, sysctl_jail_default_allow, "I",
3596     "Processes in jail are limited to creating UNIX/IP/route sockets only (deprecated)");
3597 SYSCTL_PROC(_security_jail, OID_AUTO, sysvipc_allowed,
3598     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
3599     NULL, PR_ALLOW_SYSVIPC, sysctl_jail_default_allow, "I",
3600     "Processes in jail can use System V IPC primitives (deprecated)");
3601 SYSCTL_PROC(_security_jail, OID_AUTO, allow_raw_sockets,
3602     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
3603     NULL, PR_ALLOW_RAW_SOCKETS, sysctl_jail_default_allow, "I",
3604     "Prison root can create raw sockets (deprecated)");
3605 SYSCTL_PROC(_security_jail, OID_AUTO, chflags_allowed,
3606     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
3607     NULL, PR_ALLOW_CHFLAGS, sysctl_jail_default_allow, "I",
3608     "Processes in jail can alter system file flags (deprecated)");
3609 SYSCTL_PROC(_security_jail, OID_AUTO, mount_allowed,
3610     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
3611     NULL, PR_ALLOW_MOUNT, sysctl_jail_default_allow, "I",
3612     "Processes in jail can mount/unmount jail-friendly file systems (deprecated)");
3613 
3614 static int
3615 sysctl_jail_default_level(SYSCTL_HANDLER_ARGS)
3616 {
3617 	struct prison *pr;
3618 	int level, error;
3619 
3620 	pr = req->td->td_ucred->cr_prison;
3621 	level = (pr == &prison0) ? *(int *)arg1 : *(int *)((char *)pr + arg2);
3622 	error = sysctl_handle_int(oidp, &level, 0, req);
3623 	if (error || !req->newptr)
3624 		return (error);
3625 	*(int *)arg1 = level;
3626 	return (0);
3627 }
3628 
3629 SYSCTL_PROC(_security_jail, OID_AUTO, enforce_statfs,
3630     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
3631     &jail_default_enforce_statfs, offsetof(struct prison, pr_enforce_statfs),
3632     sysctl_jail_default_level, "I",
3633     "Processes in jail cannot see all mounted file systems (deprecated)");
3634 
3635 SYSCTL_PROC(_security_jail, OID_AUTO, devfs_ruleset,
3636     CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
3637     &jail_default_devfs_rsnum, offsetof(struct prison, pr_devfs_rsnum),
3638     sysctl_jail_default_level, "I",
3639     "Ruleset for the devfs filesystem in jail (deprecated)");
3640 
3641 /*
3642  * Nodes to describe jail parameters.  Maximum length of string parameters
3643  * is returned in the string itself, and the other parameters exist merely
3644  * to make themselves and their types known.
3645  */
3646 SYSCTL_NODE(_security_jail, OID_AUTO, param, CTLFLAG_RW, 0,
3647     "Jail parameters");
3648 
3649 int
3650 sysctl_jail_param(SYSCTL_HANDLER_ARGS)
3651 {
3652 	int i;
3653 	long l;
3654 	size_t s;
3655 	char numbuf[12];
3656 
3657 	switch (oidp->oid_kind & CTLTYPE)
3658 	{
3659 	case CTLTYPE_LONG:
3660 	case CTLTYPE_ULONG:
3661 		l = 0;
3662 #ifdef SCTL_MASK32
3663 		if (!(req->flags & SCTL_MASK32))
3664 #endif
3665 			return (SYSCTL_OUT(req, &l, sizeof(l)));
3666 	case CTLTYPE_INT:
3667 	case CTLTYPE_UINT:
3668 		i = 0;
3669 		return (SYSCTL_OUT(req, &i, sizeof(i)));
3670 	case CTLTYPE_STRING:
3671 		snprintf(numbuf, sizeof(numbuf), "%jd", (intmax_t)arg2);
3672 		return
3673 		    (sysctl_handle_string(oidp, numbuf, sizeof(numbuf), req));
3674 	case CTLTYPE_STRUCT:
3675 		s = (size_t)arg2;
3676 		return (SYSCTL_OUT(req, &s, sizeof(s)));
3677 	}
3678 	return (0);
3679 }
3680 
3681 /*
3682  * CTLFLAG_RDTUN in the following indicates jail parameters that can be set at
3683  * jail creation time but cannot be changed in an existing jail.
3684  */
3685 SYSCTL_JAIL_PARAM(, jid, CTLTYPE_INT | CTLFLAG_RDTUN, "I", "Jail ID");
3686 SYSCTL_JAIL_PARAM(, parent, CTLTYPE_INT | CTLFLAG_RD, "I", "Jail parent ID");
3687 SYSCTL_JAIL_PARAM_STRING(, name, CTLFLAG_RW, MAXHOSTNAMELEN, "Jail name");
3688 SYSCTL_JAIL_PARAM_STRING(, path, CTLFLAG_RDTUN, MAXPATHLEN, "Jail root path");
3689 SYSCTL_JAIL_PARAM(, securelevel, CTLTYPE_INT | CTLFLAG_RW,
3690     "I", "Jail secure level");
3691 SYSCTL_JAIL_PARAM(, osreldate, CTLTYPE_INT | CTLFLAG_RDTUN, "I",
3692     "Jail value for kern.osreldate and uname -K");
3693 SYSCTL_JAIL_PARAM_STRING(, osrelease, CTLFLAG_RDTUN, OSRELEASELEN,
3694     "Jail value for kern.osrelease and uname -r");
3695 SYSCTL_JAIL_PARAM(, enforce_statfs, CTLTYPE_INT | CTLFLAG_RW,
3696     "I", "Jail cannot see all mounted file systems");
3697 SYSCTL_JAIL_PARAM(, devfs_ruleset, CTLTYPE_INT | CTLFLAG_RW,
3698     "I", "Ruleset for in-jail devfs mounts");
3699 SYSCTL_JAIL_PARAM(, persist, CTLTYPE_INT | CTLFLAG_RW,
3700     "B", "Jail persistence");
3701 #ifdef VIMAGE
3702 SYSCTL_JAIL_PARAM(, vnet, CTLTYPE_INT | CTLFLAG_RDTUN,
3703     "E,jailsys", "Virtual network stack");
3704 #endif
3705 SYSCTL_JAIL_PARAM(, dying, CTLTYPE_INT | CTLFLAG_RD,
3706     "B", "Jail is in the process of shutting down");
3707 
3708 SYSCTL_JAIL_PARAM_NODE(children, "Number of child jails");
3709 SYSCTL_JAIL_PARAM(_children, cur, CTLTYPE_INT | CTLFLAG_RD,
3710     "I", "Current number of child jails");
3711 SYSCTL_JAIL_PARAM(_children, max, CTLTYPE_INT | CTLFLAG_RW,
3712     "I", "Maximum number of child jails");
3713 
3714 SYSCTL_JAIL_PARAM_SYS_NODE(host, CTLFLAG_RW, "Jail host info");
3715 SYSCTL_JAIL_PARAM_STRING(_host, hostname, CTLFLAG_RW, MAXHOSTNAMELEN,
3716     "Jail hostname");
3717 SYSCTL_JAIL_PARAM_STRING(_host, domainname, CTLFLAG_RW, MAXHOSTNAMELEN,
3718     "Jail NIS domainname");
3719 SYSCTL_JAIL_PARAM_STRING(_host, hostuuid, CTLFLAG_RW, HOSTUUIDLEN,
3720     "Jail host UUID");
3721 SYSCTL_JAIL_PARAM(_host, hostid, CTLTYPE_ULONG | CTLFLAG_RW,
3722     "LU", "Jail host ID");
3723 
3724 SYSCTL_JAIL_PARAM_NODE(cpuset, "Jail cpuset");
3725 SYSCTL_JAIL_PARAM(_cpuset, id, CTLTYPE_INT | CTLFLAG_RD, "I", "Jail cpuset ID");
3726 
3727 #ifdef INET
3728 SYSCTL_JAIL_PARAM_SYS_NODE(ip4, CTLFLAG_RDTUN,
3729     "Jail IPv4 address virtualization");
3730 SYSCTL_JAIL_PARAM_STRUCT(_ip4, addr, CTLFLAG_RW, sizeof(struct in_addr),
3731     "S,in_addr,a", "Jail IPv4 addresses");
3732 SYSCTL_JAIL_PARAM(_ip4, saddrsel, CTLTYPE_INT | CTLFLAG_RW,
3733     "B", "Do (not) use IPv4 source address selection rather than the "
3734     "primary jail IPv4 address.");
3735 #endif
3736 #ifdef INET6
3737 SYSCTL_JAIL_PARAM_SYS_NODE(ip6, CTLFLAG_RDTUN,
3738     "Jail IPv6 address virtualization");
3739 SYSCTL_JAIL_PARAM_STRUCT(_ip6, addr, CTLFLAG_RW, sizeof(struct in6_addr),
3740     "S,in6_addr,a", "Jail IPv6 addresses");
3741 SYSCTL_JAIL_PARAM(_ip6, saddrsel, CTLTYPE_INT | CTLFLAG_RW,
3742     "B", "Do (not) use IPv6 source address selection rather than the "
3743     "primary jail IPv6 address.");
3744 #endif
3745 
3746 SYSCTL_JAIL_PARAM_NODE(allow, "Jail permission flags");
3747 SYSCTL_JAIL_PARAM(_allow, set_hostname, CTLTYPE_INT | CTLFLAG_RW,
3748     "B", "Jail may set hostname");
3749 SYSCTL_JAIL_PARAM(_allow, sysvipc, CTLTYPE_INT | CTLFLAG_RW,
3750     "B", "Jail may use SYSV IPC");
3751 SYSCTL_JAIL_PARAM(_allow, raw_sockets, CTLTYPE_INT | CTLFLAG_RW,
3752     "B", "Jail may create raw sockets");
3753 SYSCTL_JAIL_PARAM(_allow, chflags, CTLTYPE_INT | CTLFLAG_RW,
3754     "B", "Jail may alter system file flags");
3755 SYSCTL_JAIL_PARAM(_allow, quotas, CTLTYPE_INT | CTLFLAG_RW,
3756     "B", "Jail may set file quotas");
3757 SYSCTL_JAIL_PARAM(_allow, socket_af, CTLTYPE_INT | CTLFLAG_RW,
3758     "B", "Jail may create sockets other than just UNIX/IPv4/IPv6/route");
3759 SYSCTL_JAIL_PARAM(_allow, mlock, CTLTYPE_INT | CTLFLAG_RW,
3760     "B", "Jail may lock (unlock) physical pages in memory");
3761 SYSCTL_JAIL_PARAM(_allow, reserved_ports, CTLTYPE_INT | CTLFLAG_RW,
3762     "B", "Jail may bind sockets to reserved ports");
3763 SYSCTL_JAIL_PARAM(_allow, read_msgbuf, CTLTYPE_INT | CTLFLAG_RW,
3764     "B", "Jail may read the kernel message buffer");
3765 SYSCTL_JAIL_PARAM(_allow, unprivileged_proc_debug, CTLTYPE_INT | CTLFLAG_RW,
3766     "B", "Unprivileged processes may use process debugging facilities");
3767 
3768 SYSCTL_JAIL_PARAM_SUBNODE(allow, mount, "Jail mount/unmount permission flags");
3769 SYSCTL_JAIL_PARAM(_allow_mount, , CTLTYPE_INT | CTLFLAG_RW,
3770     "B", "Jail may mount/unmount jail-friendly file systems in general");
3771 
3772 /*
3773  * Add a dynamic parameter allow.<name>, or allow.<prefix>.<name>.  Return
3774  * its associated bit in the pr_allow bitmask, or zero if the parameter was
3775  * not created.
3776  */
3777 unsigned
3778 prison_add_allow(const char *prefix, const char *name, const char *prefix_descr,
3779     const char *descr)
3780 {
3781 	struct bool_flags *bf;
3782 	struct sysctl_oid *parent;
3783 	char *allow_name, *allow_noname, *allowed;
3784 #ifndef NO_SYSCTL_DESCR
3785 	char *descr_deprecated;
3786 #endif
3787 	unsigned allow_flag;
3788 
3789 	if (prefix
3790 	    ? asprintf(&allow_name, M_PRISON, "allow.%s.%s", prefix, name)
3791 		< 0 ||
3792 	      asprintf(&allow_noname, M_PRISON, "allow.%s.no%s", prefix, name)
3793 		< 0
3794 	    : asprintf(&allow_name, M_PRISON, "allow.%s", name) < 0 ||
3795 	      asprintf(&allow_noname, M_PRISON, "allow.no%s", name) < 0) {
3796 		free(allow_name, M_PRISON);
3797 		return 0;
3798 	}
3799 
3800 	/*
3801 	 * See if this parameter has already beed added, i.e. a module was
3802 	 * previously loaded/unloaded.
3803 	 */
3804 	mtx_lock(&prison0.pr_mtx);
3805 	for (bf = pr_flag_allow;
3806 	     bf < pr_flag_allow + nitems(pr_flag_allow) && bf->flag != 0;
3807 	     bf++) {
3808 		if (strcmp(bf->name, allow_name) == 0) {
3809 			allow_flag = bf->flag;
3810 			goto no_add;
3811 		}
3812 	}
3813 
3814 	/*
3815 	 * Find a free bit in prison0's pr_allow, failing if there are none
3816 	 * (which shouldn't happen as long as we keep track of how many
3817 	 * potential dynamic flags exist).
3818 	 *
3819 	 * Due to per-jail unprivileged process debugging support
3820 	 * using pr_allow, also verify against PR_ALLOW_ALL_STATIC.
3821 	 * prison0 may have unprivileged process debugging unset.
3822 	 */
3823 	for (allow_flag = 1;; allow_flag <<= 1) {
3824 		if (allow_flag == 0)
3825 			goto no_add;
3826 		if (allow_flag & PR_ALLOW_ALL_STATIC)
3827 			continue;
3828 		if ((prison0.pr_allow & allow_flag) == 0)
3829 			break;
3830 	}
3831 
3832 	/*
3833 	 * Note the parameter in the next open slot in pr_flag_allow.
3834 	 * Set the flag last so code that checks pr_flag_allow can do so
3835 	 * without locking.
3836 	 */
3837 	for (bf = pr_flag_allow; bf->flag != 0; bf++)
3838 		if (bf == pr_flag_allow + nitems(pr_flag_allow)) {
3839 			/* This should never happen, but is not fatal. */
3840 			allow_flag = 0;
3841 			goto no_add;
3842 		}
3843 	prison0.pr_allow |= allow_flag;
3844 	bf->name = allow_name;
3845 	bf->noname = allow_noname;
3846 	bf->flag = allow_flag;
3847 	mtx_unlock(&prison0.pr_mtx);
3848 
3849 	/*
3850 	 * Create sysctls for the paramter, and the back-compat global
3851 	 * permission.
3852 	 */
3853 	parent = prefix
3854 	    ? SYSCTL_ADD_NODE(NULL,
3855 		  SYSCTL_CHILDREN(&sysctl___security_jail_param_allow),
3856 		  OID_AUTO, prefix, 0, 0, prefix_descr)
3857 	    : &sysctl___security_jail_param_allow;
3858 	(void)SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(parent), OID_AUTO,
3859 	    name, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
3860 	    NULL, 0, sysctl_jail_param, "B", descr);
3861 	if ((prefix
3862 	     ? asprintf(&allowed, M_TEMP, "%s_%s_allowed", prefix, name)
3863 	     : asprintf(&allowed, M_TEMP, "%s_allowed", name)) >= 0) {
3864 #ifndef NO_SYSCTL_DESCR
3865 		(void)asprintf(&descr_deprecated, M_TEMP, "%s (deprecated)",
3866 		    descr);
3867 #endif
3868 		(void)SYSCTL_ADD_PROC(NULL,
3869 		    SYSCTL_CHILDREN(&sysctl___security_jail), OID_AUTO, allowed,
3870 		    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, NULL, allow_flag,
3871 		    sysctl_jail_default_allow, "I", descr_deprecated);
3872 #ifndef NO_SYSCTL_DESCR
3873 		free(descr_deprecated, M_TEMP);
3874 #endif
3875 		free(allowed, M_TEMP);
3876 	}
3877 	return allow_flag;
3878 
3879  no_add:
3880 	mtx_unlock(&prison0.pr_mtx);
3881 	free(allow_name, M_PRISON);
3882 	free(allow_noname, M_PRISON);
3883 	return allow_flag;
3884 }
3885 
3886 /*
3887  * The VFS system will register jail-aware filesystems here.  They each get
3888  * a parameter allow.mount.xxxfs and a flag to check when a jailed user
3889  * attempts to mount.
3890  */
3891 void
3892 prison_add_vfs(struct vfsconf *vfsp)
3893 {
3894 #ifdef NO_SYSCTL_DESCR
3895 
3896 	vfsp->vfc_prison_flag = prison_add_allow("mount", vfsp->vfc_name,
3897 	    NULL, NULL);
3898 #else
3899 	char *descr;
3900 
3901 	(void)asprintf(&descr, M_TEMP, "Jail may mount the %s file system",
3902 	    vfsp->vfc_name);
3903 	vfsp->vfc_prison_flag = prison_add_allow("mount", vfsp->vfc_name,
3904 	    NULL, descr);
3905 	free(descr, M_TEMP);
3906 #endif
3907 }
3908 
3909 #ifdef RACCT
3910 void
3911 prison_racct_foreach(void (*callback)(struct racct *racct,
3912     void *arg2, void *arg3), void (*pre)(void), void (*post)(void),
3913     void *arg2, void *arg3)
3914 {
3915 	struct prison_racct *prr;
3916 
3917 	ASSERT_RACCT_ENABLED();
3918 
3919 	sx_slock(&allprison_lock);
3920 	if (pre != NULL)
3921 		(pre)();
3922 	LIST_FOREACH(prr, &allprison_racct, prr_next)
3923 		(callback)(prr->prr_racct, arg2, arg3);
3924 	if (post != NULL)
3925 		(post)();
3926 	sx_sunlock(&allprison_lock);
3927 }
3928 
3929 static struct prison_racct *
3930 prison_racct_find_locked(const char *name)
3931 {
3932 	struct prison_racct *prr;
3933 
3934 	ASSERT_RACCT_ENABLED();
3935 	sx_assert(&allprison_lock, SA_XLOCKED);
3936 
3937 	if (name[0] == '\0' || strlen(name) >= MAXHOSTNAMELEN)
3938 		return (NULL);
3939 
3940 	LIST_FOREACH(prr, &allprison_racct, prr_next) {
3941 		if (strcmp(name, prr->prr_name) != 0)
3942 			continue;
3943 
3944 		/* Found prison_racct with a matching name? */
3945 		prison_racct_hold(prr);
3946 		return (prr);
3947 	}
3948 
3949 	/* Add new prison_racct. */
3950 	prr = malloc(sizeof(*prr), M_PRISON_RACCT, M_ZERO | M_WAITOK);
3951 	racct_create(&prr->prr_racct);
3952 
3953 	strcpy(prr->prr_name, name);
3954 	refcount_init(&prr->prr_refcount, 1);
3955 	LIST_INSERT_HEAD(&allprison_racct, prr, prr_next);
3956 
3957 	return (prr);
3958 }
3959 
3960 struct prison_racct *
3961 prison_racct_find(const char *name)
3962 {
3963 	struct prison_racct *prr;
3964 
3965 	ASSERT_RACCT_ENABLED();
3966 
3967 	sx_xlock(&allprison_lock);
3968 	prr = prison_racct_find_locked(name);
3969 	sx_xunlock(&allprison_lock);
3970 	return (prr);
3971 }
3972 
3973 void
3974 prison_racct_hold(struct prison_racct *prr)
3975 {
3976 
3977 	ASSERT_RACCT_ENABLED();
3978 
3979 	refcount_acquire(&prr->prr_refcount);
3980 }
3981 
3982 static void
3983 prison_racct_free_locked(struct prison_racct *prr)
3984 {
3985 
3986 	ASSERT_RACCT_ENABLED();
3987 	sx_assert(&allprison_lock, SA_XLOCKED);
3988 
3989 	if (refcount_release(&prr->prr_refcount)) {
3990 		racct_destroy(&prr->prr_racct);
3991 		LIST_REMOVE(prr, prr_next);
3992 		free(prr, M_PRISON_RACCT);
3993 	}
3994 }
3995 
3996 void
3997 prison_racct_free(struct prison_racct *prr)
3998 {
3999 
4000 	ASSERT_RACCT_ENABLED();
4001 	sx_assert(&allprison_lock, SA_UNLOCKED);
4002 
4003 	if (refcount_release_if_not_last(&prr->prr_refcount))
4004 		return;
4005 
4006 	sx_xlock(&allprison_lock);
4007 	prison_racct_free_locked(prr);
4008 	sx_xunlock(&allprison_lock);
4009 }
4010 
4011 static void
4012 prison_racct_attach(struct prison *pr)
4013 {
4014 	struct prison_racct *prr;
4015 
4016 	ASSERT_RACCT_ENABLED();
4017 	sx_assert(&allprison_lock, SA_XLOCKED);
4018 
4019 	prr = prison_racct_find_locked(pr->pr_name);
4020 	KASSERT(prr != NULL, ("cannot find prison_racct"));
4021 
4022 	pr->pr_prison_racct = prr;
4023 }
4024 
4025 /*
4026  * Handle jail renaming.  From the racct point of view, renaming means
4027  * moving from one prison_racct to another.
4028  */
4029 static void
4030 prison_racct_modify(struct prison *pr)
4031 {
4032 #ifdef RCTL
4033 	struct proc *p;
4034 	struct ucred *cred;
4035 #endif
4036 	struct prison_racct *oldprr;
4037 
4038 	ASSERT_RACCT_ENABLED();
4039 
4040 	sx_slock(&allproc_lock);
4041 	sx_xlock(&allprison_lock);
4042 
4043 	if (strcmp(pr->pr_name, pr->pr_prison_racct->prr_name) == 0) {
4044 		sx_xunlock(&allprison_lock);
4045 		sx_sunlock(&allproc_lock);
4046 		return;
4047 	}
4048 
4049 	oldprr = pr->pr_prison_racct;
4050 	pr->pr_prison_racct = NULL;
4051 
4052 	prison_racct_attach(pr);
4053 
4054 	/*
4055 	 * Move resource utilisation records.
4056 	 */
4057 	racct_move(pr->pr_prison_racct->prr_racct, oldprr->prr_racct);
4058 
4059 #ifdef RCTL
4060 	/*
4061 	 * Force rctl to reattach rules to processes.
4062 	 */
4063 	FOREACH_PROC_IN_SYSTEM(p) {
4064 		PROC_LOCK(p);
4065 		cred = crhold(p->p_ucred);
4066 		PROC_UNLOCK(p);
4067 		rctl_proc_ucred_changed(p, cred);
4068 		crfree(cred);
4069 	}
4070 #endif
4071 
4072 	sx_sunlock(&allproc_lock);
4073 	prison_racct_free_locked(oldprr);
4074 	sx_xunlock(&allprison_lock);
4075 }
4076 
4077 static void
4078 prison_racct_detach(struct prison *pr)
4079 {
4080 
4081 	ASSERT_RACCT_ENABLED();
4082 	sx_assert(&allprison_lock, SA_UNLOCKED);
4083 
4084 	if (pr->pr_prison_racct == NULL)
4085 		return;
4086 	prison_racct_free(pr->pr_prison_racct);
4087 	pr->pr_prison_racct = NULL;
4088 }
4089 #endif /* RACCT */
4090 
4091 #ifdef DDB
4092 
4093 static void
4094 db_show_prison(struct prison *pr)
4095 {
4096 	struct bool_flags *bf;
4097 	struct jailsys_flags *jsf;
4098 #if defined(INET) || defined(INET6)
4099 	int ii;
4100 #endif
4101 	unsigned f;
4102 #ifdef INET
4103 	char ip4buf[INET_ADDRSTRLEN];
4104 #endif
4105 #ifdef INET6
4106 	char ip6buf[INET6_ADDRSTRLEN];
4107 #endif
4108 
4109 	db_printf("prison %p:\n", pr);
4110 	db_printf(" jid             = %d\n", pr->pr_id);
4111 	db_printf(" name            = %s\n", pr->pr_name);
4112 	db_printf(" parent          = %p\n", pr->pr_parent);
4113 	db_printf(" ref             = %d\n", pr->pr_ref);
4114 	db_printf(" uref            = %d\n", pr->pr_uref);
4115 	db_printf(" path            = %s\n", pr->pr_path);
4116 	db_printf(" cpuset          = %d\n", pr->pr_cpuset
4117 	    ? pr->pr_cpuset->cs_id : -1);
4118 #ifdef VIMAGE
4119 	db_printf(" vnet            = %p\n", pr->pr_vnet);
4120 #endif
4121 	db_printf(" root            = %p\n", pr->pr_root);
4122 	db_printf(" securelevel     = %d\n", pr->pr_securelevel);
4123 	db_printf(" devfs_rsnum     = %d\n", pr->pr_devfs_rsnum);
4124 	db_printf(" children.max    = %d\n", pr->pr_childmax);
4125 	db_printf(" children.cur    = %d\n", pr->pr_childcount);
4126 	db_printf(" child           = %p\n", LIST_FIRST(&pr->pr_children));
4127 	db_printf(" sibling         = %p\n", LIST_NEXT(pr, pr_sibling));
4128 	db_printf(" flags           = 0x%x", pr->pr_flags);
4129 	for (bf = pr_flag_bool; bf < pr_flag_bool + nitems(pr_flag_bool); bf++)
4130 		if (pr->pr_flags & bf->flag)
4131 			db_printf(" %s", bf->name);
4132 	for (jsf = pr_flag_jailsys;
4133 	     jsf < pr_flag_jailsys + nitems(pr_flag_jailsys);
4134 	     jsf++) {
4135 		f = pr->pr_flags & (jsf->disable | jsf->new);
4136 		db_printf(" %-16s= %s\n", jsf->name,
4137 		    (f != 0 && f == jsf->disable) ? "disable"
4138 		    : (f == jsf->new) ? "new"
4139 		    : "inherit");
4140 	}
4141 	db_printf(" allow           = 0x%x", pr->pr_allow);
4142 	for (bf = pr_flag_allow;
4143 	     bf < pr_flag_allow + nitems(pr_flag_allow) && bf->flag != 0;
4144 	     bf++)
4145 		if (pr->pr_allow & bf->flag)
4146 			db_printf(" %s", bf->name);
4147 	db_printf("\n");
4148 	db_printf(" enforce_statfs  = %d\n", pr->pr_enforce_statfs);
4149 	db_printf(" host.hostname   = %s\n", pr->pr_hostname);
4150 	db_printf(" host.domainname = %s\n", pr->pr_domainname);
4151 	db_printf(" host.hostuuid   = %s\n", pr->pr_hostuuid);
4152 	db_printf(" host.hostid     = %lu\n", pr->pr_hostid);
4153 #ifdef INET
4154 	db_printf(" ip4s            = %d\n", pr->pr_ip4s);
4155 	for (ii = 0; ii < pr->pr_ip4s; ii++)
4156 		db_printf(" %s %s\n",
4157 		    ii == 0 ? "ip4.addr        =" : "                 ",
4158 		    inet_ntoa_r(pr->pr_ip4[ii], ip4buf));
4159 #endif
4160 #ifdef INET6
4161 	db_printf(" ip6s            = %d\n", pr->pr_ip6s);
4162 	for (ii = 0; ii < pr->pr_ip6s; ii++)
4163 		db_printf(" %s %s\n",
4164 		    ii == 0 ? "ip6.addr        =" : "                 ",
4165 		    ip6_sprintf(ip6buf, &pr->pr_ip6[ii]));
4166 #endif
4167 }
4168 
4169 DB_SHOW_COMMAND(prison, db_show_prison_command)
4170 {
4171 	struct prison *pr;
4172 
4173 	if (!have_addr) {
4174 		/*
4175 		 * Show all prisons in the list, and prison0 which is not
4176 		 * listed.
4177 		 */
4178 		db_show_prison(&prison0);
4179 		if (!db_pager_quit) {
4180 			TAILQ_FOREACH(pr, &allprison, pr_list) {
4181 				db_show_prison(pr);
4182 				if (db_pager_quit)
4183 					break;
4184 			}
4185 		}
4186 		return;
4187 	}
4188 
4189 	if (addr == 0)
4190 		pr = &prison0;
4191 	else {
4192 		/* Look for a prison with the ID and with references. */
4193 		TAILQ_FOREACH(pr, &allprison, pr_list)
4194 			if (pr->pr_id == addr && pr->pr_ref > 0)
4195 				break;
4196 		if (pr == NULL)
4197 			/* Look again, without requiring a reference. */
4198 			TAILQ_FOREACH(pr, &allprison, pr_list)
4199 				if (pr->pr_id == addr)
4200 					break;
4201 		if (pr == NULL)
4202 			/* Assume address points to a valid prison. */
4203 			pr = (struct prison *)addr;
4204 	}
4205 	db_show_prison(pr);
4206 }
4207 
4208 #endif /* DDB */
4209