xref: /freebsd-14-stable/sys/kern/kern_jail.c (revision c1d7552dddb5276c8d1cfe2b8c533646164e2f7a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 #include "opt_ddb.h"
33 #include "opt_inet.h"
34 #include "opt_inet6.h"
35 #include "opt_nfs.h"
36 
37 #include <sys/param.h>
38 #include <sys/types.h>
39 #include <sys/kernel.h>
40 #include <sys/systm.h>
41 #include <sys/errno.h>
42 #include <sys/sysproto.h>
43 #include <sys/malloc.h>
44 #include <sys/osd.h>
45 #include <sys/priv.h>
46 #include <sys/proc.h>
47 #include <sys/epoch.h>
48 #include <sys/taskqueue.h>
49 #include <sys/fcntl.h>
50 #include <sys/jail.h>
51 #include <sys/linker.h>
52 #include <sys/lock.h>
53 #include <sys/mman.h>
54 #include <sys/mutex.h>
55 #include <sys/racct.h>
56 #include <sys/rctl.h>
57 #include <sys/refcount.h>
58 #include <sys/sx.h>
59 #include <sys/sysent.h>
60 #include <sys/namei.h>
61 #include <sys/mount.h>
62 #include <sys/queue.h>
63 #include <sys/socket.h>
64 #include <sys/syscallsubr.h>
65 #include <sys/sysctl.h>
66 #include <sys/uuid.h>
67 #include <sys/vnode.h>
68 
69 #include <net/if.h>
70 #include <net/vnet.h>
71 
72 #include <netinet/in.h>
73 
74 #ifdef DDB
75 #include <ddb/ddb.h>
76 #endif /* DDB */
77 
78 #include <security/mac/mac_framework.h>
79 
80 #define	PRISON0_HOSTUUID_MODULE	"hostuuid"
81 
82 MALLOC_DEFINE(M_PRISON, "prison", "Prison structures");
83 static MALLOC_DEFINE(M_PRISON_RACCT, "prison_racct", "Prison racct structures");
84 
85 /* Keep struct prison prison0 and some code in kern_jail_set() readable. */
86 #ifdef INET
87 #ifdef INET6
88 #define	_PR_IP_SADDRSEL	PR_IP4_SADDRSEL|PR_IP6_SADDRSEL
89 #else
90 #define	_PR_IP_SADDRSEL	PR_IP4_SADDRSEL
91 #endif
92 #else /* !INET */
93 #ifdef INET6
94 #define	_PR_IP_SADDRSEL	PR_IP6_SADDRSEL
95 #else
96 #define	_PR_IP_SADDRSEL	0
97 #endif
98 #endif
99 
100 /* prison0 describes what is "real" about the system. */
101 struct prison prison0 = {
102 	.pr_id		= 0,
103 	.pr_name	= "0",
104 	.pr_ref		= 1,
105 	.pr_uref	= 1,
106 	.pr_path	= "/",
107 	.pr_securelevel	= -1,
108 	.pr_devfs_rsnum = 0,
109 	.pr_state	= PRISON_STATE_ALIVE,
110 	.pr_childmax	= JAIL_MAX,
111 	.pr_hostuuid	= DEFAULT_HOSTUUID,
112 	.pr_children	= LIST_HEAD_INITIALIZER(prison0.pr_children),
113 #ifdef VIMAGE
114 	.pr_flags	= PR_HOST|PR_VNET|_PR_IP_SADDRSEL,
115 #else
116 	.pr_flags	= PR_HOST|_PR_IP_SADDRSEL,
117 #endif
118 	.pr_allow	= PR_ALLOW_ALL_STATIC,
119 };
120 MTX_SYSINIT(prison0, &prison0.pr_mtx, "jail mutex", MTX_DEF);
121 
122 struct bool_flags {
123 	const char	*name;
124 	const char	*noname;
125 	volatile u_int	 flag;
126 };
127 struct jailsys_flags {
128 	const char	*name;
129 	unsigned	 disable;
130 	unsigned	 new;
131 };
132 
133 /*
134  * Handle jail teardown in a dedicated thread to avoid deadlocks from
135  * vnet_destroy().
136  */
137 TASKQUEUE_DEFINE_THREAD(jail_remove);
138 
139 /* allprison, allprison_racct and lastprid are protected by allprison_lock. */
140 struct	sx allprison_lock;
141 SX_SYSINIT(allprison_lock, &allprison_lock, "allprison");
142 struct	prisonlist allprison = TAILQ_HEAD_INITIALIZER(allprison);
143 LIST_HEAD(, prison_racct) allprison_racct;
144 int	lastprid = 0;
145 
146 static int get_next_prid(struct prison **insprp);
147 static int do_jail_attach(struct thread *td, struct prison *pr, int drflags);
148 static void prison_complete(void *context, int pending);
149 static void prison_deref(struct prison *pr, int flags);
150 static void prison_deref_kill(struct prison *pr, struct prisonlist *freeprison);
151 static int prison_lock_xlock(struct prison *pr, int flags);
152 static void prison_cleanup(struct prison *pr);
153 static void prison_free_not_last(struct prison *pr);
154 static void prison_proc_free_not_last(struct prison *pr);
155 static void prison_proc_relink(struct prison *opr, struct prison *npr,
156     struct proc *p);
157 static void prison_set_allow_locked(struct prison *pr, unsigned flag,
158     int enable);
159 static char *prison_path(struct prison *pr1, struct prison *pr2);
160 #ifdef RACCT
161 static void prison_racct_attach(struct prison *pr);
162 static void prison_racct_modify(struct prison *pr);
163 static void prison_racct_detach(struct prison *pr);
164 #endif
165 
166 /* Flags for prison_deref */
167 #define	PD_DEREF	0x01	/* Decrement pr_ref */
168 #define	PD_DEUREF	0x02	/* Decrement pr_uref */
169 #define	PD_KILL		0x04	/* Remove jail, kill processes, etc */
170 #define	PD_LOCKED	0x10	/* pr_mtx is held */
171 #define	PD_LIST_SLOCKED	0x20	/* allprison_lock is held shared */
172 #define	PD_LIST_XLOCKED	0x40	/* allprison_lock is held exclusive */
173 #define PD_OP_FLAGS	0x07	/* Operation flags */
174 #define PD_LOCK_FLAGS	0x70	/* Lock status flags */
175 
176 /*
177  * Parameter names corresponding to PR_* flag values.  Size values are for kvm
178  * as we cannot figure out the size of a sparse array, or an array without a
179  * terminating entry.
180  */
181 static struct bool_flags pr_flag_bool[] = {
182 	{"persist", "nopersist", PR_PERSIST},
183 #ifdef INET
184 	{"ip4.saddrsel", "ip4.nosaddrsel", PR_IP4_SADDRSEL},
185 #endif
186 #ifdef INET6
187 	{"ip6.saddrsel", "ip6.nosaddrsel", PR_IP6_SADDRSEL},
188 #endif
189 };
190 const size_t pr_flag_bool_size = sizeof(pr_flag_bool);
191 
192 static struct jailsys_flags pr_flag_jailsys[] = {
193 	{"host", 0, PR_HOST},
194 #ifdef VIMAGE
195 	{"vnet", 0, PR_VNET},
196 #endif
197 #ifdef INET
198 	{"ip4", PR_IP4_USER, PR_IP4_USER},
199 #endif
200 #ifdef INET6
201 	{"ip6", PR_IP6_USER, PR_IP6_USER},
202 #endif
203 };
204 const size_t pr_flag_jailsys_size = sizeof(pr_flag_jailsys);
205 
206 /*
207  * Make this array full-size so dynamic parameters can be added.
208  * It is protected by prison0.mtx, but lockless reading is allowed
209  * with an atomic check of the flag values.
210  */
211 static struct bool_flags pr_flag_allow[NBBY * NBPW] = {
212 	{"allow.set_hostname", "allow.noset_hostname", PR_ALLOW_SET_HOSTNAME},
213 	{"allow.sysvipc", "allow.nosysvipc", PR_ALLOW_SYSVIPC},
214 	{"allow.raw_sockets", "allow.noraw_sockets", PR_ALLOW_RAW_SOCKETS},
215 	{"allow.chflags", "allow.nochflags", PR_ALLOW_CHFLAGS},
216 	{"allow.mount", "allow.nomount", PR_ALLOW_MOUNT},
217 	{"allow.quotas", "allow.noquotas", PR_ALLOW_QUOTAS},
218 	{"allow.socket_af", "allow.nosocket_af", PR_ALLOW_SOCKET_AF},
219 	{"allow.mlock", "allow.nomlock", PR_ALLOW_MLOCK},
220 	{"allow.reserved_ports", "allow.noreserved_ports",
221 	 PR_ALLOW_RESERVED_PORTS},
222 	{"allow.read_msgbuf", "allow.noread_msgbuf", PR_ALLOW_READ_MSGBUF},
223 	{"allow.unprivileged_proc_debug", "allow.nounprivileged_proc_debug",
224 	 PR_ALLOW_UNPRIV_DEBUG},
225 	{"allow.suser", "allow.nosuser", PR_ALLOW_SUSER},
226 #ifdef VIMAGE
227 	{"allow.nfsd", "allow.nonfsd", PR_ALLOW_NFSD},
228 #endif
229 };
230 static unsigned pr_allow_all = PR_ALLOW_ALL_STATIC;
231 const size_t pr_flag_allow_size = sizeof(pr_flag_allow);
232 
233 #define	JAIL_DEFAULT_ALLOW		(PR_ALLOW_SET_HOSTNAME | \
234 					 PR_ALLOW_RESERVED_PORTS | \
235 					 PR_ALLOW_UNPRIV_DEBUG | \
236 					 PR_ALLOW_SUSER)
237 #define	JAIL_DEFAULT_ENFORCE_STATFS	2
238 #define	JAIL_DEFAULT_DEVFS_RSNUM	0
239 static unsigned jail_default_allow = JAIL_DEFAULT_ALLOW;
240 static int jail_default_enforce_statfs = JAIL_DEFAULT_ENFORCE_STATFS;
241 static int jail_default_devfs_rsnum = JAIL_DEFAULT_DEVFS_RSNUM;
242 #if defined(INET) || defined(INET6)
243 static unsigned jail_max_af_ips = 255;
244 #endif
245 
246 /*
247  * Initialize the parts of prison0 that can't be static-initialized with
248  * constants.  This is called from proc0_init() after creating thread0 cpuset.
249  */
250 void
prison0_init(void)251 prison0_init(void)
252 {
253 	uint8_t *file, *data;
254 	size_t size;
255 	char buf[sizeof(prison0.pr_hostuuid)];
256 	bool valid;
257 
258 	prison0.pr_cpuset = cpuset_ref(thread0.td_cpuset);
259 	prison0.pr_osreldate = osreldate;
260 	strlcpy(prison0.pr_osrelease, osrelease, sizeof(prison0.pr_osrelease));
261 
262 	/* If we have a preloaded hostuuid, use it. */
263 	file = preload_search_by_type(PRISON0_HOSTUUID_MODULE);
264 	if (file != NULL) {
265 		data = preload_fetch_addr(file);
266 		size = preload_fetch_size(file);
267 		if (data != NULL) {
268 			/*
269 			 * The preloaded data may include trailing whitespace, almost
270 			 * certainly a newline; skip over any whitespace or
271 			 * non-printable characters to be safe.
272 			 */
273 			while (size > 0 && data[size - 1] <= 0x20) {
274 				size--;
275 			}
276 
277 			valid = false;
278 
279 			/*
280 			 * Not NUL-terminated when passed from loader, but
281 			 * validate_uuid requires that due to using sscanf (as
282 			 * does the subsequent strlcpy, since it still reads
283 			 * past the given size to return the true length);
284 			 * bounce to a temporary buffer to fix.
285 			 */
286 			if (size >= sizeof(buf))
287 				goto done;
288 
289 			memcpy(buf, data, size);
290 			buf[size] = '\0';
291 
292 			if (validate_uuid(buf, size, NULL, 0) != 0)
293 				goto done;
294 
295 			valid = true;
296 			(void)strlcpy(prison0.pr_hostuuid, buf,
297 			    sizeof(prison0.pr_hostuuid));
298 
299 done:
300 			if (bootverbose && !valid) {
301 				printf("hostuuid: preload data malformed: '%.*s'\n",
302 				    (int)size, data);
303 			}
304 		}
305 	}
306 	if (bootverbose)
307 		printf("hostuuid: using %s\n", prison0.pr_hostuuid);
308 }
309 
310 /*
311  * struct jail_args {
312  *	struct jail *jail;
313  * };
314  */
315 int
sys_jail(struct thread * td,struct jail_args * uap)316 sys_jail(struct thread *td, struct jail_args *uap)
317 {
318 	uint32_t version;
319 	int error;
320 	struct jail j;
321 
322 	error = copyin(uap->jail, &version, sizeof(uint32_t));
323 	if (error)
324 		return (error);
325 
326 	switch (version) {
327 	case 0:
328 	{
329 		struct jail_v0 j0;
330 
331 		/* FreeBSD single IPv4 jails. */
332 		bzero(&j, sizeof(struct jail));
333 		error = copyin(uap->jail, &j0, sizeof(struct jail_v0));
334 		if (error)
335 			return (error);
336 		j.version = j0.version;
337 		j.path = j0.path;
338 		j.hostname = j0.hostname;
339 		j.ip4s = htonl(j0.ip_number);	/* jail_v0 is host order */
340 		break;
341 	}
342 
343 	case 1:
344 		/*
345 		 * Version 1 was used by multi-IPv4 jail implementations
346 		 * that never made it into the official kernel.
347 		 */
348 		return (EINVAL);
349 
350 	case 2:	/* JAIL_API_VERSION */
351 		/* FreeBSD multi-IPv4/IPv6,noIP jails. */
352 		error = copyin(uap->jail, &j, sizeof(struct jail));
353 		if (error)
354 			return (error);
355 		break;
356 
357 	default:
358 		/* Sci-Fi jails are not supported, sorry. */
359 		return (EINVAL);
360 	}
361 	return (kern_jail(td, &j));
362 }
363 
364 int
kern_jail(struct thread * td,struct jail * j)365 kern_jail(struct thread *td, struct jail *j)
366 {
367 	struct iovec optiov[2 * (4 + nitems(pr_flag_allow)
368 #ifdef INET
369 			    + 1
370 #endif
371 #ifdef INET6
372 			    + 1
373 #endif
374 			    )];
375 	struct uio opt;
376 	char *u_path, *u_hostname, *u_name;
377 	struct bool_flags *bf;
378 #ifdef INET
379 	uint32_t ip4s;
380 	struct in_addr *u_ip4;
381 #endif
382 #ifdef INET6
383 	struct in6_addr *u_ip6;
384 #endif
385 	size_t tmplen;
386 	int error, enforce_statfs;
387 
388 	bzero(&optiov, sizeof(optiov));
389 	opt.uio_iov = optiov;
390 	opt.uio_iovcnt = 0;
391 	opt.uio_offset = -1;
392 	opt.uio_resid = -1;
393 	opt.uio_segflg = UIO_SYSSPACE;
394 	opt.uio_rw = UIO_READ;
395 	opt.uio_td = td;
396 
397 	/* Set permissions for top-level jails from sysctls. */
398 	if (!jailed(td->td_ucred)) {
399 		for (bf = pr_flag_allow;
400 		     bf < pr_flag_allow + nitems(pr_flag_allow) &&
401 			atomic_load_int(&bf->flag) != 0;
402 		     bf++) {
403 			optiov[opt.uio_iovcnt].iov_base = __DECONST(char *,
404 			    (jail_default_allow & bf->flag)
405 			    ? bf->name : bf->noname);
406 			optiov[opt.uio_iovcnt].iov_len =
407 			    strlen(optiov[opt.uio_iovcnt].iov_base) + 1;
408 			opt.uio_iovcnt += 2;
409 		}
410 		optiov[opt.uio_iovcnt].iov_base = "enforce_statfs";
411 		optiov[opt.uio_iovcnt].iov_len = sizeof("enforce_statfs");
412 		opt.uio_iovcnt++;
413 		enforce_statfs = jail_default_enforce_statfs;
414 		optiov[opt.uio_iovcnt].iov_base = &enforce_statfs;
415 		optiov[opt.uio_iovcnt].iov_len = sizeof(enforce_statfs);
416 		opt.uio_iovcnt++;
417 	}
418 
419 	tmplen = MAXPATHLEN + MAXHOSTNAMELEN + MAXHOSTNAMELEN;
420 #ifdef INET
421 	ip4s = (j->version == 0) ? 1 : j->ip4s;
422 	if (ip4s > jail_max_af_ips)
423 		return (EINVAL);
424 	tmplen += ip4s * sizeof(struct in_addr);
425 #else
426 	if (j->ip4s > 0)
427 		return (EINVAL);
428 #endif
429 #ifdef INET6
430 	if (j->ip6s > jail_max_af_ips)
431 		return (EINVAL);
432 	tmplen += j->ip6s * sizeof(struct in6_addr);
433 #else
434 	if (j->ip6s > 0)
435 		return (EINVAL);
436 #endif
437 	u_path = malloc(tmplen, M_TEMP, M_WAITOK);
438 	u_hostname = u_path + MAXPATHLEN;
439 	u_name = u_hostname + MAXHOSTNAMELEN;
440 #ifdef INET
441 	u_ip4 = (struct in_addr *)(u_name + MAXHOSTNAMELEN);
442 #endif
443 #ifdef INET6
444 #ifdef INET
445 	u_ip6 = (struct in6_addr *)(u_ip4 + ip4s);
446 #else
447 	u_ip6 = (struct in6_addr *)(u_name + MAXHOSTNAMELEN);
448 #endif
449 #endif
450 	optiov[opt.uio_iovcnt].iov_base = "path";
451 	optiov[opt.uio_iovcnt].iov_len = sizeof("path");
452 	opt.uio_iovcnt++;
453 	optiov[opt.uio_iovcnt].iov_base = u_path;
454 	error = copyinstr(j->path, u_path, MAXPATHLEN,
455 	    &optiov[opt.uio_iovcnt].iov_len);
456 	if (error) {
457 		free(u_path, M_TEMP);
458 		return (error);
459 	}
460 	opt.uio_iovcnt++;
461 	optiov[opt.uio_iovcnt].iov_base = "host.hostname";
462 	optiov[opt.uio_iovcnt].iov_len = sizeof("host.hostname");
463 	opt.uio_iovcnt++;
464 	optiov[opt.uio_iovcnt].iov_base = u_hostname;
465 	error = copyinstr(j->hostname, u_hostname, MAXHOSTNAMELEN,
466 	    &optiov[opt.uio_iovcnt].iov_len);
467 	if (error) {
468 		free(u_path, M_TEMP);
469 		return (error);
470 	}
471 	opt.uio_iovcnt++;
472 	if (j->jailname != NULL) {
473 		optiov[opt.uio_iovcnt].iov_base = "name";
474 		optiov[opt.uio_iovcnt].iov_len = sizeof("name");
475 		opt.uio_iovcnt++;
476 		optiov[opt.uio_iovcnt].iov_base = u_name;
477 		error = copyinstr(j->jailname, u_name, MAXHOSTNAMELEN,
478 		    &optiov[opt.uio_iovcnt].iov_len);
479 		if (error) {
480 			free(u_path, M_TEMP);
481 			return (error);
482 		}
483 		opt.uio_iovcnt++;
484 	}
485 #ifdef INET
486 	optiov[opt.uio_iovcnt].iov_base = "ip4.addr";
487 	optiov[opt.uio_iovcnt].iov_len = sizeof("ip4.addr");
488 	opt.uio_iovcnt++;
489 	optiov[opt.uio_iovcnt].iov_base = u_ip4;
490 	optiov[opt.uio_iovcnt].iov_len = ip4s * sizeof(struct in_addr);
491 	if (j->version == 0)
492 		u_ip4->s_addr = j->ip4s;
493 	else {
494 		error = copyin(j->ip4, u_ip4, optiov[opt.uio_iovcnt].iov_len);
495 		if (error) {
496 			free(u_path, M_TEMP);
497 			return (error);
498 		}
499 	}
500 	opt.uio_iovcnt++;
501 #endif
502 #ifdef INET6
503 	optiov[opt.uio_iovcnt].iov_base = "ip6.addr";
504 	optiov[opt.uio_iovcnt].iov_len = sizeof("ip6.addr");
505 	opt.uio_iovcnt++;
506 	optiov[opt.uio_iovcnt].iov_base = u_ip6;
507 	optiov[opt.uio_iovcnt].iov_len = j->ip6s * sizeof(struct in6_addr);
508 	error = copyin(j->ip6, u_ip6, optiov[opt.uio_iovcnt].iov_len);
509 	if (error) {
510 		free(u_path, M_TEMP);
511 		return (error);
512 	}
513 	opt.uio_iovcnt++;
514 #endif
515 	KASSERT(opt.uio_iovcnt <= nitems(optiov),
516 		("kern_jail: too many iovecs (%d)", opt.uio_iovcnt));
517 	error = kern_jail_set(td, &opt, JAIL_CREATE | JAIL_ATTACH);
518 	free(u_path, M_TEMP);
519 	return (error);
520 }
521 
522 /*
523  * struct jail_set_args {
524  *	struct iovec *iovp;
525  *	unsigned int iovcnt;
526  *	int flags;
527  * };
528  */
529 int
sys_jail_set(struct thread * td,struct jail_set_args * uap)530 sys_jail_set(struct thread *td, struct jail_set_args *uap)
531 {
532 	struct uio *auio;
533 	int error;
534 
535 	/* Check that we have an even number of iovecs. */
536 	if (uap->iovcnt & 1)
537 		return (EINVAL);
538 
539 	error = copyinuio(uap->iovp, uap->iovcnt, &auio);
540 	if (error)
541 		return (error);
542 	error = kern_jail_set(td, auio, uap->flags);
543 	freeuio(auio);
544 	return (error);
545 }
546 
547 #if defined(INET) || defined(INET6)
548 typedef int prison_addr_cmp_t(const void *, const void *);
549 typedef bool prison_addr_valid_t(const void *);
550 static const struct pr_family {
551 	size_t			size;
552 	prison_addr_cmp_t	*cmp;
553 	prison_addr_valid_t	*valid;
554 	int			ip_flag;
555 } pr_families[PR_FAMILY_MAX] = {
556 #ifdef INET
557 	[PR_INET] = {
558 		.size = sizeof(struct in_addr),
559 		.cmp = prison_qcmp_v4,
560 		.valid = prison_valid_v4,
561 		.ip_flag = PR_IP4_USER,
562 	 },
563 #endif
564 #ifdef INET6
565 	[PR_INET6] = {
566 		.size = sizeof(struct in6_addr),
567 		.cmp = prison_qcmp_v6,
568 		.valid = prison_valid_v6,
569 		.ip_flag = PR_IP6_USER,
570 	},
571 #endif
572 };
573 
574 /*
575  * Network address lists (pr_addrs) allocation for jails.  The addresses
576  * are accessed locklessly by the network stack, thus need to be protected by
577  * the network epoch.
578  */
579 struct prison_ip {
580 	struct epoch_context ctx;
581 	uint32_t	ips;
582 #ifdef FUTURE_C
583 	/*
584 	 * XXX Variable-length automatic arrays in union may be
585 	 * supported in future C.
586 	 */
587 	union {
588 		char pr_ip[];
589 		struct in_addr pr_ip4[];
590 		struct in6_addr pr_ip6[];
591 	};
592 #else /* No future C :( */
593 	char pr_ip[];
594 #endif
595 };
596 
597 static char *
PR_IP(struct prison_ip * pip,const pr_family_t af,int idx)598 PR_IP(struct prison_ip *pip, const pr_family_t af, int idx)
599 {
600 	MPASS(pip);
601 	MPASS(af < PR_FAMILY_MAX);
602 	MPASS(idx >= 0 && idx < pip->ips);
603 
604 	return (pip->pr_ip + pr_families[af].size * idx);
605 }
606 
607 static struct prison_ip *
prison_ip_alloc(const pr_family_t af,uint32_t cnt,int flags)608 prison_ip_alloc(const pr_family_t af, uint32_t cnt, int flags)
609 {
610 	struct prison_ip *pip;
611 
612 	pip = malloc(sizeof(struct prison_ip) + cnt * pr_families[af].size,
613 	    M_PRISON, flags);
614 	if (pip != NULL)
615 		pip->ips = cnt;
616 	return (pip);
617 }
618 
619 /*
620  * Allocate and copyin user supplied address list, sorting and validating.
621  * kern_jail_set() helper.
622  */
623 static struct prison_ip *
prison_ip_copyin(const pr_family_t af,void * op,uint32_t cnt)624 prison_ip_copyin(const pr_family_t af, void *op, uint32_t cnt)
625 {
626 	prison_addr_cmp_t *const cmp = pr_families[af].cmp;
627 	const size_t size = pr_families[af].size;
628 	struct prison_ip *pip;
629 
630 	pip = prison_ip_alloc(af, cnt, M_WAITOK);
631 	bcopy(op, pip->pr_ip, cnt * size);
632 	/*
633 	 * IP addresses are all sorted but ip[0] to preserve
634 	 * the primary IP address as given from userland.
635 	 * This special IP is used for unbound outgoing
636 	 * connections as well for "loopback" traffic in case
637 	 * source address selection cannot find any more fitting
638 	 * address to connect from.
639 	 */
640 	if (cnt > 1)
641 		qsort(PR_IP(pip, af, 1), cnt - 1, size, cmp);
642 	/*
643 	 * Check for duplicate addresses and do some simple
644 	 * zero and broadcast checks. If users give other bogus
645 	 * addresses it is their problem.
646 	 */
647 	for (int i = 0; i < cnt; i++) {
648 		if (!pr_families[af].valid(PR_IP(pip, af, i))) {
649 			free(pip, M_PRISON);
650 			return (NULL);
651 		}
652 		if (i + 1 < cnt &&
653 		    (cmp(PR_IP(pip, af, 0), PR_IP(pip, af, i + 1)) == 0 ||
654 		     cmp(PR_IP(pip, af, i), PR_IP(pip, af, i + 1)) == 0)) {
655 			free(pip, M_PRISON);
656 			return (NULL);
657 		}
658 	}
659 
660 	return (pip);
661 }
662 
663 /*
664  * Allocate and dup parent prison address list.
665  * kern_jail_set() helper.
666  */
667 static void
prison_ip_dup(struct prison * ppr,struct prison * pr,const pr_family_t af)668 prison_ip_dup(struct prison *ppr, struct prison *pr, const pr_family_t af)
669 {
670 	const struct prison_ip *ppip = ppr->pr_addrs[af];
671 	struct prison_ip *pip;
672 
673 	if (ppip != NULL) {
674 		pip = prison_ip_alloc(af, ppip->ips, M_WAITOK);
675 		bcopy(ppip->pr_ip, pip->pr_ip, pip->ips * pr_families[af].size);
676 		pr->pr_addrs[af] = pip;
677 	}
678 }
679 
680 /*
681  * Make sure the new set of IP addresses is a subset of the parent's list.
682  * Don't worry about the parent being unlocked, as any setting is done with
683  * allprison_lock held.
684  * kern_jail_set() helper.
685  */
686 static bool
prison_ip_parent_match(struct prison_ip * ppip,struct prison_ip * pip,const pr_family_t af)687 prison_ip_parent_match(struct prison_ip *ppip, struct prison_ip *pip,
688     const pr_family_t af)
689 {
690 	prison_addr_cmp_t *const cmp = pr_families[af].cmp;
691 	int i, j;
692 
693 	if (ppip == NULL)
694 		return (false);
695 
696 	for (i = 0; i < ppip->ips; i++)
697 		if (cmp(PR_IP(pip, af, 0), PR_IP(ppip, af, i)) == 0)
698 			break;
699 
700 	if (i == ppip->ips)
701 		/* Main address not present in parent. */
702 		return (false);
703 
704 	if (pip->ips > 1) {
705 		for (i = j = 1; i < pip->ips; i++) {
706 			if (cmp(PR_IP(pip, af, i), PR_IP(ppip, af, 0)) == 0)
707 				/* Equals to parent primary address. */
708 				continue;
709 			for (; j < ppip->ips; j++)
710 				if (cmp(PR_IP(pip, af, i),
711 				    PR_IP(ppip, af, j)) == 0)
712 					break;
713 			if (j == ppip->ips)
714 				break;
715 		}
716 		if (j == ppip->ips)
717 			/* Address not present in parent. */
718 			return (false);
719 	}
720 	return (true);
721 }
722 
723 /*
724  * Check for conflicting IP addresses.  We permit them if there is no more
725  * than one IP on each jail.  If there is a duplicate on a jail with more
726  * than one IP stop checking and return error.
727  * kern_jail_set() helper.
728  */
729 static bool
prison_ip_conflict_check(const struct prison * ppr,const struct prison * pr,struct prison_ip * pip,pr_family_t af)730 prison_ip_conflict_check(const struct prison *ppr, const struct prison *pr,
731     struct prison_ip *pip, pr_family_t af)
732 {
733 	const struct prison *tppr, *tpr;
734 	int descend;
735 
736 #ifdef VIMAGE
737 	for (tppr = ppr; tppr != &prison0; tppr = tppr->pr_parent)
738 		if (tppr->pr_flags & PR_VNET)
739 			break;
740 #else
741 	tppr = &prison0;
742 #endif
743 	FOREACH_PRISON_DESCENDANT(tppr, tpr, descend) {
744 		if (tpr == pr ||
745 #ifdef VIMAGE
746 		    (tpr != tppr && (tpr->pr_flags & PR_VNET)) ||
747 #endif
748 		    !prison_isalive(tpr)) {
749 			descend = 0;
750 			continue;
751 		}
752 		if (!(tpr->pr_flags & pr_families[af].ip_flag))
753 			continue;
754 		descend = 0;
755 		if (tpr->pr_addrs[af] == NULL ||
756 		    (pip->ips == 1 && tpr->pr_addrs[af]->ips == 1))
757 			continue;
758 		for (int i = 0; i < pip->ips; i++)
759 			if (prison_ip_check(tpr, af, PR_IP(pip, af, i)) == 0)
760 				return (false);
761 	}
762 
763 	return (true);
764 }
765 
766 _Static_assert(offsetof(struct prison_ip, ctx) == 0,
767     "prison must start with epoch context");
768 static void
prison_ip_free_deferred(epoch_context_t ctx)769 prison_ip_free_deferred(epoch_context_t ctx)
770 {
771 
772 	free(ctx, M_PRISON);
773 }
774 
775 static void
prison_ip_free(struct prison_ip * pip)776 prison_ip_free(struct prison_ip *pip)
777 {
778 
779 	if (pip != NULL)
780 		NET_EPOCH_CALL(prison_ip_free_deferred, &pip->ctx);
781 }
782 
783 static void
prison_ip_set(struct prison * pr,const pr_family_t af,struct prison_ip * new)784 prison_ip_set(struct prison *pr, const pr_family_t af, struct prison_ip *new)
785 {
786 	struct prison_ip **mem, *old;
787 
788 	mtx_assert(&pr->pr_mtx, MA_OWNED);
789 
790 	mem = &pr->pr_addrs[af];
791 
792 	old = *mem;
793 	atomic_store_ptr(mem, new);
794 	prison_ip_free(old);
795 }
796 
797 /*
798  * Restrict a prison's IP address list with its parent's, possibly replacing
799  * it.  Return true if succeed, otherwise should redo.
800  * kern_jail_set() helper.
801  */
802 static bool
prison_ip_restrict(struct prison * pr,const pr_family_t af,struct prison_ip ** newp)803 prison_ip_restrict(struct prison *pr, const pr_family_t af,
804     struct prison_ip **newp)
805 {
806 	struct prison_ip *ppip = pr->pr_parent->pr_addrs[af];
807 	struct prison_ip *pip = pr->pr_addrs[af];
808 	int (*const cmp)(const void *, const void *) = pr_families[af].cmp;
809 	const size_t size = pr_families[af].size;
810 	struct prison_ip *new = newp != NULL ? *newp : NULL;
811 	uint32_t ips;
812 
813 	mtx_assert(&pr->pr_mtx, MA_OWNED);
814 
815 	/*
816 	 * Due to epoch-synchronized access to the IP address lists we always
817 	 * allocate a new list even if the old one has enough space.  We could
818 	 * atomically update an IPv4 address inside a list, but that would
819 	 * screw up sorting, and in case of IPv6 we can't even atomically write
820 	 * one.
821 	 */
822 	if (ppip == NULL) {
823 		if (pip != NULL)
824 			prison_ip_set(pr, af, NULL);
825 		return (true);
826 	}
827 
828 	if (!(pr->pr_flags & pr_families[af].ip_flag)) {
829 		if (new == NULL) {
830 			new = prison_ip_alloc(af, ppip->ips, M_NOWAIT);
831 			if (new == NULL)
832 				return (false); /* Redo */
833 		}
834 		/* This has no user settings, so just copy the parent's list. */
835 		MPASS(new->ips == ppip->ips);
836 		bcopy(ppip->pr_ip, new->pr_ip, ppip->ips * size);
837 		prison_ip_set(pr, af, new);
838 		if (newp != NULL)
839 			*newp = NULL; /* Used */
840 	} else if (pip != NULL) {
841 		/* Remove addresses that aren't in the parent. */
842 		int i;
843 
844 		i = 0; /* index in pip */
845 		ips = 0; /* index in new */
846 
847 		if (new == NULL) {
848 			new = prison_ip_alloc(af, pip->ips, M_NOWAIT);
849 			if (new == NULL)
850 				return (false); /* Redo */
851 		}
852 
853 		for (int pi = 0; pi < ppip->ips; pi++)
854 			if (cmp(PR_IP(pip, af, 0), PR_IP(ppip, af, pi)) == 0) {
855 				/* Found our primary address in parent. */
856 				bcopy(PR_IP(pip, af, i), PR_IP(new, af, ips),
857 				    size);
858 				i++;
859 				ips++;
860 				break;
861 			}
862 		for (int pi = 1; i < pip->ips; ) {
863 			/* Check against primary, which is unsorted. */
864 			if (cmp(PR_IP(pip, af, i), PR_IP(ppip, af, 0)) == 0) {
865 				/* Matches parent's primary address. */
866 				bcopy(PR_IP(pip, af, i), PR_IP(new, af, ips),
867 				    size);
868 				i++;
869 				ips++;
870 				continue;
871 			}
872 			/* The rest are sorted. */
873 			switch (pi >= ppip->ips ? -1 :
874 				cmp(PR_IP(pip, af, i), PR_IP(ppip, af, pi))) {
875 			case -1:
876 				i++;
877 				break;
878 			case 0:
879 				bcopy(PR_IP(pip, af, i), PR_IP(new, af, ips),
880 				    size);
881 				i++;
882 				pi++;
883 				ips++;
884 				break;
885 			case 1:
886 				pi++;
887 				break;
888 			}
889 		}
890 		if (ips == 0) {
891 			if (newp == NULL || *newp == NULL)
892 				prison_ip_free(new);
893 			new = NULL;
894 		} else {
895 			/* Shrink to real size */
896 			KASSERT((new->ips >= ips),
897 			    ("Out-of-bounds write to prison_ip %p", new));
898 			new->ips = ips;
899 		}
900 		prison_ip_set(pr, af, new);
901 		if (newp != NULL)
902 			*newp = NULL; /* Used */
903 	}
904 	return (true);
905 }
906 
907 /*
908  * Fast-path check if an address belongs to a prison.
909  */
910 int
prison_ip_check(const struct prison * pr,const pr_family_t af,const void * addr)911 prison_ip_check(const struct prison *pr, const pr_family_t af,
912     const void *addr)
913 {
914 	int (*const cmp)(const void *, const void *) = pr_families[af].cmp;
915 	struct prison_ip *pip;
916 	int i, a, z, d;
917 
918 	MPASS(mtx_owned(&pr->pr_mtx) ||
919 	    in_epoch(net_epoch_preempt) ||
920 	    sx_xlocked(&allprison_lock));
921 
922 	pip = atomic_load_ptr(&pr->pr_addrs[af]);
923 	if (__predict_false(pip == NULL))
924 		return (EAFNOSUPPORT);
925 
926 	/* Check the primary IP. */
927 	if (cmp(PR_IP(pip, af, 0), addr) == 0)
928 		return (0);
929 
930 	/*
931 	 * All the other IPs are sorted so we can do a binary search.
932 	 */
933 	a = 0;
934 	z = pip->ips - 2;
935 	while (a <= z) {
936 		i = (a + z) / 2;
937 		d = cmp(PR_IP(pip, af, i + 1), addr);
938 		if (d > 0)
939 			z = i - 1;
940 		else if (d < 0)
941 			a = i + 1;
942 		else
943 			return (0);
944 	}
945 
946 	return (EADDRNOTAVAIL);
947 }
948 
949 /*
950  * Grab primary IP.  Historically required mutex, but nothing prevents
951  * us to support epoch-protected access.  Is it used in fast path?
952  * in{6}_jail.c helper
953  */
954 const void *
prison_ip_get0(const struct prison * pr,const pr_family_t af)955 prison_ip_get0(const struct prison *pr, const pr_family_t af)
956 {
957 	const struct prison_ip *pip = pr->pr_addrs[af];
958 
959 	mtx_assert(&pr->pr_mtx, MA_OWNED);
960 	MPASS(pip);
961 
962 	return (pip->pr_ip);
963 }
964 
965 u_int
prison_ip_cnt(const struct prison * pr,const pr_family_t af)966 prison_ip_cnt(const struct prison *pr, const pr_family_t af)
967 {
968 
969 	return (pr->pr_addrs[af]->ips);
970 }
971 #endif	/* defined(INET) || defined(INET6) */
972 
973 int
kern_jail_set(struct thread * td,struct uio * optuio,int flags)974 kern_jail_set(struct thread *td, struct uio *optuio, int flags)
975 {
976 	struct nameidata nd;
977 #ifdef INET
978 	struct prison_ip *ip4;
979 #endif
980 #ifdef INET6
981 	struct prison_ip *ip6;
982 #endif
983 	struct vfsopt *opt;
984 	struct vfsoptlist *opts;
985 	struct prison *pr, *deadpr, *inspr, *mypr, *ppr, *tpr;
986 	struct vnode *root;
987 	char *domain, *errmsg, *host, *name, *namelc, *p, *path, *uuid;
988 	char *g_path, *osrelstr;
989 	struct bool_flags *bf;
990 	struct jailsys_flags *jsf;
991 #if defined(INET) || defined(INET6)
992 	void *op;
993 #endif
994 	unsigned long hid;
995 	size_t namelen, onamelen, pnamelen;
996 	int born, created, cuflags, descend, drflags, enforce;
997 	int error, errmsg_len, errmsg_pos;
998 	int gotchildmax, gotenforce, gothid, gotrsnum, gotslevel;
999 	int jid, jsys, len, level;
1000 	int childmax, osreldt, rsnum, slevel;
1001 #ifdef INET
1002 	int ip4s;
1003 	bool redo_ip4;
1004 #endif
1005 #ifdef INET6
1006 	int ip6s;
1007 	bool redo_ip6;
1008 #endif
1009 	uint64_t pr_allow, ch_allow, pr_flags, ch_flags;
1010 	uint64_t pr_allow_diff;
1011 	unsigned tallow;
1012 	char numbuf[12];
1013 
1014 	error = priv_check(td, PRIV_JAIL_SET);
1015 	if (!error && (flags & JAIL_ATTACH))
1016 		error = priv_check(td, PRIV_JAIL_ATTACH);
1017 	if (error)
1018 		return (error);
1019 	mypr = td->td_ucred->cr_prison;
1020 	if ((flags & JAIL_CREATE) && mypr->pr_childmax == 0)
1021 		return (EPERM);
1022 	if (flags & ~JAIL_SET_MASK)
1023 		return (EINVAL);
1024 
1025 	/*
1026 	 * Check all the parameters before committing to anything.  Not all
1027 	 * errors can be caught early, but we may as well try.  Also, this
1028 	 * takes care of some expensive stuff (path lookup) before getting
1029 	 * the allprison lock.
1030 	 *
1031 	 * XXX Jails are not filesystems, and jail parameters are not mount
1032 	 *     options.  But it makes more sense to re-use the vfsopt code
1033 	 *     than duplicate it under a different name.
1034 	 */
1035 	error = vfs_buildopts(optuio, &opts);
1036 	if (error)
1037 		return (error);
1038 #ifdef INET
1039 	ip4 = NULL;
1040 #endif
1041 #ifdef INET6
1042 	ip6 = NULL;
1043 #endif
1044 	g_path = NULL;
1045 
1046 	cuflags = flags & (JAIL_CREATE | JAIL_UPDATE);
1047 	if (!cuflags) {
1048 		error = EINVAL;
1049 		vfs_opterror(opts, "no valid operation (create or update)");
1050 		goto done_errmsg;
1051 	}
1052 
1053 	error = vfs_copyopt(opts, "jid", &jid, sizeof(jid));
1054 	if (error == ENOENT)
1055 		jid = 0;
1056 	else if (error != 0)
1057 		goto done_free;
1058 
1059 	error = vfs_copyopt(opts, "securelevel", &slevel, sizeof(slevel));
1060 	if (error == ENOENT)
1061 		gotslevel = 0;
1062 	else if (error != 0)
1063 		goto done_free;
1064 	else
1065 		gotslevel = 1;
1066 
1067 	error =
1068 	    vfs_copyopt(opts, "children.max", &childmax, sizeof(childmax));
1069 	if (error == ENOENT)
1070 		gotchildmax = 0;
1071 	else if (error != 0)
1072 		goto done_free;
1073 	else
1074 		gotchildmax = 1;
1075 
1076 	error = vfs_copyopt(opts, "enforce_statfs", &enforce, sizeof(enforce));
1077 	if (error == ENOENT)
1078 		gotenforce = 0;
1079 	else if (error != 0)
1080 		goto done_free;
1081 	else if (enforce < 0 || enforce > 2) {
1082 		error = EINVAL;
1083 		goto done_free;
1084 	} else
1085 		gotenforce = 1;
1086 
1087 	error = vfs_copyopt(opts, "devfs_ruleset", &rsnum, sizeof(rsnum));
1088 	if (error == ENOENT)
1089 		gotrsnum = 0;
1090 	else if (error != 0)
1091 		goto done_free;
1092 	else
1093 		gotrsnum = 1;
1094 
1095 	pr_flags = ch_flags = 0;
1096 	for (bf = pr_flag_bool;
1097 	     bf < pr_flag_bool + nitems(pr_flag_bool);
1098 	     bf++) {
1099 		vfs_flagopt(opts, bf->name, &pr_flags, bf->flag);
1100 		vfs_flagopt(opts, bf->noname, &ch_flags, bf->flag);
1101 	}
1102 	ch_flags |= pr_flags;
1103 	for (jsf = pr_flag_jailsys;
1104 	     jsf < pr_flag_jailsys + nitems(pr_flag_jailsys);
1105 	     jsf++) {
1106 		error = vfs_copyopt(opts, jsf->name, &jsys, sizeof(jsys));
1107 		if (error == ENOENT)
1108 			continue;
1109 		if (error != 0)
1110 			goto done_free;
1111 		switch (jsys) {
1112 		case JAIL_SYS_DISABLE:
1113 			if (!jsf->disable) {
1114 				error = EINVAL;
1115 				goto done_free;
1116 			}
1117 			pr_flags |= jsf->disable;
1118 			break;
1119 		case JAIL_SYS_NEW:
1120 			pr_flags |= jsf->new;
1121 			break;
1122 		case JAIL_SYS_INHERIT:
1123 			break;
1124 		default:
1125 			error = EINVAL;
1126 			goto done_free;
1127 		}
1128 		ch_flags |= jsf->new | jsf->disable;
1129 	}
1130 	if ((flags & (JAIL_CREATE | JAIL_ATTACH)) == JAIL_CREATE
1131 	    && !(pr_flags & PR_PERSIST)) {
1132 		error = EINVAL;
1133 		vfs_opterror(opts, "new jail must persist or attach");
1134 		goto done_errmsg;
1135 	}
1136 #ifdef VIMAGE
1137 	if ((flags & JAIL_UPDATE) && (ch_flags & PR_VNET)) {
1138 		error = EINVAL;
1139 		vfs_opterror(opts, "vnet cannot be changed after creation");
1140 		goto done_errmsg;
1141 	}
1142 #endif
1143 #ifdef INET
1144 	if ((flags & JAIL_UPDATE) && (ch_flags & PR_IP4_USER)) {
1145 		error = EINVAL;
1146 		vfs_opterror(opts, "ip4 cannot be changed after creation");
1147 		goto done_errmsg;
1148 	}
1149 #endif
1150 #ifdef INET6
1151 	if ((flags & JAIL_UPDATE) && (ch_flags & PR_IP6_USER)) {
1152 		error = EINVAL;
1153 		vfs_opterror(opts, "ip6 cannot be changed after creation");
1154 		goto done_errmsg;
1155 	}
1156 #endif
1157 
1158 	pr_allow = ch_allow = 0;
1159 	for (bf = pr_flag_allow;
1160 	     bf < pr_flag_allow + nitems(pr_flag_allow) &&
1161 		atomic_load_int(&bf->flag) != 0;
1162 	     bf++) {
1163 		vfs_flagopt(opts, bf->name, &pr_allow, bf->flag);
1164 		vfs_flagopt(opts, bf->noname, &ch_allow, bf->flag);
1165 	}
1166 	ch_allow |= pr_allow;
1167 
1168 	error = vfs_getopt(opts, "name", (void **)&name, &len);
1169 	if (error == ENOENT)
1170 		name = NULL;
1171 	else if (error != 0)
1172 		goto done_free;
1173 	else {
1174 		if (len == 0 || name[len - 1] != '\0') {
1175 			error = EINVAL;
1176 			goto done_free;
1177 		}
1178 		if (len > MAXHOSTNAMELEN) {
1179 			error = ENAMETOOLONG;
1180 			goto done_free;
1181 		}
1182 	}
1183 
1184 	error = vfs_getopt(opts, "host.hostname", (void **)&host, &len);
1185 	if (error == ENOENT)
1186 		host = NULL;
1187 	else if (error != 0)
1188 		goto done_free;
1189 	else {
1190 		ch_flags |= PR_HOST;
1191 		pr_flags |= PR_HOST;
1192 		if (len == 0 || host[len - 1] != '\0') {
1193 			error = EINVAL;
1194 			goto done_free;
1195 		}
1196 		if (len > MAXHOSTNAMELEN) {
1197 			error = ENAMETOOLONG;
1198 			goto done_free;
1199 		}
1200 	}
1201 
1202 	error = vfs_getopt(opts, "host.domainname", (void **)&domain, &len);
1203 	if (error == ENOENT)
1204 		domain = NULL;
1205 	else if (error != 0)
1206 		goto done_free;
1207 	else {
1208 		ch_flags |= PR_HOST;
1209 		pr_flags |= PR_HOST;
1210 		if (len == 0 || domain[len - 1] != '\0') {
1211 			error = EINVAL;
1212 			goto done_free;
1213 		}
1214 		if (len > MAXHOSTNAMELEN) {
1215 			error = ENAMETOOLONG;
1216 			goto done_free;
1217 		}
1218 	}
1219 
1220 	error = vfs_getopt(opts, "host.hostuuid", (void **)&uuid, &len);
1221 	if (error == ENOENT)
1222 		uuid = NULL;
1223 	else if (error != 0)
1224 		goto done_free;
1225 	else {
1226 		ch_flags |= PR_HOST;
1227 		pr_flags |= PR_HOST;
1228 		if (len == 0 || uuid[len - 1] != '\0') {
1229 			error = EINVAL;
1230 			goto done_free;
1231 		}
1232 		if (len > HOSTUUIDLEN) {
1233 			error = ENAMETOOLONG;
1234 			goto done_free;
1235 		}
1236 	}
1237 
1238 #ifdef COMPAT_FREEBSD32
1239 	if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
1240 		uint32_t hid32;
1241 
1242 		error = vfs_copyopt(opts, "host.hostid", &hid32, sizeof(hid32));
1243 		hid = hid32;
1244 	} else
1245 #endif
1246 		error = vfs_copyopt(opts, "host.hostid", &hid, sizeof(hid));
1247 	if (error == ENOENT)
1248 		gothid = 0;
1249 	else if (error != 0)
1250 		goto done_free;
1251 	else {
1252 		gothid = 1;
1253 		ch_flags |= PR_HOST;
1254 		pr_flags |= PR_HOST;
1255 	}
1256 
1257 #ifdef INET
1258 	error = vfs_getopt(opts, "ip4.addr", &op, &ip4s);
1259 	if (error == ENOENT)
1260 		ip4s = 0;
1261 	else if (error != 0)
1262 		goto done_free;
1263 	else if (ip4s & (sizeof(struct in_addr) - 1)) {
1264 		error = EINVAL;
1265 		goto done_free;
1266 	} else {
1267 		ch_flags |= PR_IP4_USER;
1268 		pr_flags |= PR_IP4_USER;
1269 		if (ip4s > 0) {
1270 			ip4s /= sizeof(struct in_addr);
1271 			if (ip4s > jail_max_af_ips) {
1272 				error = EINVAL;
1273 				vfs_opterror(opts, "too many IPv4 addresses");
1274 				goto done_errmsg;
1275 			}
1276 			ip4 = prison_ip_copyin(PR_INET, op, ip4s);
1277 			if (ip4 == NULL) {
1278 				error = EINVAL;
1279 				goto done_free;
1280 			}
1281 		}
1282 	}
1283 #endif
1284 
1285 #ifdef INET6
1286 	error = vfs_getopt(opts, "ip6.addr", &op, &ip6s);
1287 	if (error == ENOENT)
1288 		ip6s = 0;
1289 	else if (error != 0)
1290 		goto done_free;
1291 	else if (ip6s & (sizeof(struct in6_addr) - 1)) {
1292 		error = EINVAL;
1293 		goto done_free;
1294 	} else {
1295 		ch_flags |= PR_IP6_USER;
1296 		pr_flags |= PR_IP6_USER;
1297 		if (ip6s > 0) {
1298 			ip6s /= sizeof(struct in6_addr);
1299 			if (ip6s > jail_max_af_ips) {
1300 				error = EINVAL;
1301 				vfs_opterror(opts, "too many IPv6 addresses");
1302 				goto done_errmsg;
1303 			}
1304 			ip6 = prison_ip_copyin(PR_INET6, op, ip6s);
1305 			if (ip6 == NULL) {
1306 				error = EINVAL;
1307 				goto done_free;
1308 			}
1309 		}
1310 	}
1311 #endif
1312 
1313 #if defined(VIMAGE) && (defined(INET) || defined(INET6))
1314 	if ((ch_flags & PR_VNET) && (ch_flags & (PR_IP4_USER | PR_IP6_USER))) {
1315 		error = EINVAL;
1316 		vfs_opterror(opts,
1317 		    "vnet jails cannot have IP address restrictions");
1318 		goto done_errmsg;
1319 	}
1320 #endif
1321 
1322 	error = vfs_getopt(opts, "osrelease", (void **)&osrelstr, &len);
1323 	if (error == ENOENT)
1324 		osrelstr = NULL;
1325 	else if (error != 0)
1326 		goto done_free;
1327 	else {
1328 		if (flags & JAIL_UPDATE) {
1329 			error = EINVAL;
1330 			vfs_opterror(opts,
1331 			    "osrelease cannot be changed after creation");
1332 			goto done_errmsg;
1333 		}
1334 		if (len == 0 || osrelstr[len - 1] != '\0') {
1335 			error = EINVAL;
1336 			goto done_free;
1337 		}
1338 		if (len >= OSRELEASELEN) {
1339 			error = ENAMETOOLONG;
1340 			vfs_opterror(opts,
1341 			    "osrelease string must be 1-%d bytes long",
1342 			    OSRELEASELEN - 1);
1343 			goto done_errmsg;
1344 		}
1345 	}
1346 
1347 	error = vfs_copyopt(opts, "osreldate", &osreldt, sizeof(osreldt));
1348 	if (error == ENOENT)
1349 		osreldt = 0;
1350 	else if (error != 0)
1351 		goto done_free;
1352 	else {
1353 		if (flags & JAIL_UPDATE) {
1354 			error = EINVAL;
1355 			vfs_opterror(opts,
1356 			    "osreldate cannot be changed after creation");
1357 			goto done_errmsg;
1358 		}
1359 		if (osreldt == 0) {
1360 			error = EINVAL;
1361 			vfs_opterror(opts, "osreldate cannot be 0");
1362 			goto done_errmsg;
1363 		}
1364 	}
1365 
1366 	root = NULL;
1367 	error = vfs_getopt(opts, "path", (void **)&path, &len);
1368 	if (error == ENOENT)
1369 		path = NULL;
1370 	else if (error != 0)
1371 		goto done_free;
1372 	else {
1373 		if (flags & JAIL_UPDATE) {
1374 			error = EINVAL;
1375 			vfs_opterror(opts,
1376 			    "path cannot be changed after creation");
1377 			goto done_errmsg;
1378 		}
1379 		if (len == 0 || path[len - 1] != '\0') {
1380 			error = EINVAL;
1381 			goto done_free;
1382 		}
1383 		NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, path);
1384 		error = namei(&nd);
1385 		if (error)
1386 			goto done_free;
1387 		root = nd.ni_vp;
1388 		NDFREE_PNBUF(&nd);
1389 		g_path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1390 		strlcpy(g_path, path, MAXPATHLEN);
1391 		error = vn_path_to_global_path(td, root, g_path, MAXPATHLEN);
1392 		if (error == 0) {
1393 			path = g_path;
1394 		} else {
1395 			/* exit on other errors */
1396 			goto done_free;
1397 		}
1398 		if (root->v_type != VDIR) {
1399 			error = ENOTDIR;
1400 			vput(root);
1401 			goto done_free;
1402 		}
1403 		VOP_UNLOCK(root);
1404 	}
1405 
1406 	/*
1407 	 * Find the specified jail, or at least its parent.
1408 	 * This abuses the file error codes ENOENT and EEXIST.
1409 	 */
1410 	pr = NULL;
1411 	inspr = NULL;
1412 	if (cuflags == JAIL_CREATE && jid == 0 && name != NULL) {
1413 		namelc = strrchr(name, '.');
1414 		jid = strtoul(namelc != NULL ? namelc + 1 : name, &p, 10);
1415 		if (*p != '\0')
1416 			jid = 0;
1417 	}
1418 	sx_xlock(&allprison_lock);
1419 	drflags = PD_LIST_XLOCKED;
1420 	ppr = mypr;
1421 	if (!prison_isalive(ppr)) {
1422 		/* This jail is dying.  This process will surely follow. */
1423 		error = EAGAIN;
1424 		goto done_deref;
1425 	}
1426 	if (jid != 0) {
1427 		if (jid < 0) {
1428 			error = EINVAL;
1429 			vfs_opterror(opts, "negative jid");
1430 			goto done_deref;
1431 		}
1432 		/*
1433 		 * See if a requested jid already exists.  Keep track of
1434 		 * where it can be inserted later.
1435 		 */
1436 		TAILQ_FOREACH(inspr, &allprison, pr_list) {
1437 			if (inspr->pr_id < jid)
1438 				continue;
1439 			if (inspr->pr_id > jid)
1440 				break;
1441 			pr = inspr;
1442 			mtx_lock(&pr->pr_mtx);
1443 			drflags |= PD_LOCKED;
1444 			inspr = NULL;
1445 			break;
1446 		}
1447 		if (pr != NULL) {
1448 			/* Create: jid must not exist. */
1449 			if (cuflags == JAIL_CREATE) {
1450 				/*
1451 				 * Even creators that cannot see the jail will
1452 				 * get EEXIST.
1453 				 */
1454 				error = EEXIST;
1455 				vfs_opterror(opts, "jail %d already exists",
1456 				    jid);
1457 				goto done_deref;
1458 			}
1459 			if (!prison_ischild(mypr, pr)) {
1460 				/*
1461 				 * Updaters get ENOENT if they cannot see the
1462 				 * jail.  This is true even for CREATE | UPDATE,
1463 				 * which normally cannot give this error.
1464 				 */
1465 				error = ENOENT;
1466 				vfs_opterror(opts, "jail %d not found", jid);
1467 				goto done_deref;
1468 			}
1469 			ppr = pr->pr_parent;
1470 			if (!prison_isalive(ppr)) {
1471 				error = ENOENT;
1472 				vfs_opterror(opts, "jail %d is dying",
1473 				    ppr->pr_id);
1474 				goto done_deref;
1475 			}
1476 			if (!prison_isalive(pr)) {
1477 				if (!(flags & JAIL_DYING)) {
1478 					error = ENOENT;
1479 					vfs_opterror(opts, "jail %d is dying",
1480 					    jid);
1481 					goto done_deref;
1482 				}
1483 				if ((flags & JAIL_ATTACH) ||
1484 				    (pr_flags & PR_PERSIST)) {
1485 					/*
1486 					 * A dying jail might be resurrected
1487 					 * (via attach or persist), but first
1488 					 * it must determine if another jail
1489 					 * has claimed its name.  Accomplish
1490 					 * this by implicitly re-setting the
1491 					 * name.
1492 					 */
1493 					if (name == NULL)
1494 						name = prison_name(mypr, pr);
1495 				}
1496 			}
1497 		} else {
1498 			/* Update: jid must exist. */
1499 			if (cuflags == JAIL_UPDATE) {
1500 				error = ENOENT;
1501 				vfs_opterror(opts, "jail %d not found", jid);
1502 				goto done_deref;
1503 			}
1504 		}
1505 	}
1506 	/*
1507 	 * If the caller provided a name, look for a jail by that name.
1508 	 * This has different semantics for creates and updates keyed by jid
1509 	 * (where the name must not already exist in a different jail),
1510 	 * and updates keyed by the name itself (where the name must exist
1511 	 * because that is the jail being updated).
1512 	 */
1513 	namelc = NULL;
1514 	if (name != NULL) {
1515 		namelc = strrchr(name, '.');
1516 		if (namelc == NULL)
1517 			namelc = name;
1518 		else {
1519 			/*
1520 			 * This is a hierarchical name.  Split it into the
1521 			 * parent and child names, and make sure the parent
1522 			 * exists or matches an already found jail.
1523 			 */
1524 			if (pr != NULL) {
1525 				if (strncmp(name, ppr->pr_name, namelc - name)
1526 				    || ppr->pr_name[namelc - name] != '\0') {
1527 					error = EINVAL;
1528 					vfs_opterror(opts,
1529 					    "cannot change jail's parent");
1530 					goto done_deref;
1531 				}
1532 			} else {
1533 				*namelc = '\0';
1534 				ppr = prison_find_name(mypr, name);
1535 				if (ppr == NULL) {
1536 					error = ENOENT;
1537 					vfs_opterror(opts,
1538 					    "jail \"%s\" not found", name);
1539 					goto done_deref;
1540 				}
1541 				mtx_unlock(&ppr->pr_mtx);
1542 				if (!prison_isalive(ppr)) {
1543 					error = ENOENT;
1544 					vfs_opterror(opts,
1545 					    "jail \"%s\" is dying", name);
1546 					goto done_deref;
1547 				}
1548 				*namelc = '.';
1549 			}
1550 			namelc++;
1551 		}
1552 		if (namelc[0] != '\0') {
1553 			pnamelen =
1554 			    (ppr == &prison0) ? 0 : strlen(ppr->pr_name) + 1;
1555 			deadpr = NULL;
1556 			FOREACH_PRISON_CHILD(ppr, tpr) {
1557 				if (tpr != pr &&
1558 				    !strcmp(tpr->pr_name + pnamelen, namelc)) {
1559 					if (prison_isalive(tpr)) {
1560 						if (pr == NULL &&
1561 						    cuflags != JAIL_CREATE) {
1562 							/*
1563 							 * Use this jail
1564 							 * for updates.
1565 							 */
1566 							pr = tpr;
1567 							mtx_lock(&pr->pr_mtx);
1568 							drflags |= PD_LOCKED;
1569 							break;
1570 						}
1571 						/*
1572 						 * Create, or update(jid):
1573 						 * name must not exist in an
1574 						 * active sibling jail.
1575 						 */
1576 						error = EEXIST;
1577 						vfs_opterror(opts,
1578 						   "jail \"%s\" already exists",
1579 						   name);
1580 						goto done_deref;
1581 					}
1582 					if (pr == NULL &&
1583 					    cuflags != JAIL_CREATE) {
1584 						deadpr = tpr;
1585 					}
1586 				}
1587 			}
1588 			/* If no active jail is found, use a dying one. */
1589 			if (deadpr != NULL && pr == NULL) {
1590 				if (flags & JAIL_DYING) {
1591 					pr = deadpr;
1592 					mtx_lock(&pr->pr_mtx);
1593 					drflags |= PD_LOCKED;
1594 				} else if (cuflags == JAIL_UPDATE) {
1595 					error = ENOENT;
1596 					vfs_opterror(opts,
1597 					    "jail \"%s\" is dying", name);
1598 					goto done_deref;
1599 				}
1600 			}
1601 			/* Update: name must exist if no jid. */
1602 			else if (cuflags == JAIL_UPDATE && pr == NULL) {
1603 				error = ENOENT;
1604 				vfs_opterror(opts, "jail \"%s\" not found",
1605 				    name);
1606 				goto done_deref;
1607 			}
1608 		}
1609 	}
1610 	/* Update: must provide a jid or name. */
1611 	else if (cuflags == JAIL_UPDATE && pr == NULL) {
1612 		error = ENOENT;
1613 		vfs_opterror(opts, "update specified no jail");
1614 		goto done_deref;
1615 	}
1616 
1617 	/* If there's no prison to update, create a new one and link it in. */
1618 	created = pr == NULL;
1619 	if (created) {
1620 		for (tpr = mypr; tpr != NULL; tpr = tpr->pr_parent)
1621 			if (tpr->pr_childcount >= tpr->pr_childmax) {
1622 				error = EPERM;
1623 				vfs_opterror(opts, "prison limit exceeded");
1624 				goto done_deref;
1625 			}
1626 		if (jid == 0 && (jid = get_next_prid(&inspr)) == 0) {
1627 			error = EAGAIN;
1628 			vfs_opterror(opts, "no available jail IDs");
1629 			goto done_deref;
1630 		}
1631 
1632 		pr = malloc(sizeof(*pr), M_PRISON, M_WAITOK | M_ZERO);
1633 		pr->pr_state = PRISON_STATE_INVALID;
1634 		refcount_init(&pr->pr_ref, 1);
1635 		refcount_init(&pr->pr_uref, 0);
1636 		drflags |= PD_DEREF;
1637 		LIST_INIT(&pr->pr_children);
1638 		mtx_init(&pr->pr_mtx, "jail mutex", NULL, MTX_DEF | MTX_DUPOK);
1639 		TASK_INIT(&pr->pr_task, 0, prison_complete, pr);
1640 
1641 		pr->pr_id = jid;
1642 		if (inspr != NULL)
1643 			TAILQ_INSERT_BEFORE(inspr, pr, pr_list);
1644 		else
1645 			TAILQ_INSERT_TAIL(&allprison, pr, pr_list);
1646 
1647 		pr->pr_parent = ppr;
1648 		prison_hold(ppr);
1649 		prison_proc_hold(ppr);
1650 		LIST_INSERT_HEAD(&ppr->pr_children, pr, pr_sibling);
1651 		for (tpr = ppr; tpr != NULL; tpr = tpr->pr_parent)
1652 			tpr->pr_childcount++;
1653 
1654 		/* Set some default values, and inherit some from the parent. */
1655 		if (namelc == NULL)
1656 			namelc = "";
1657 		if (path == NULL) {
1658 			path = "/";
1659 			root = mypr->pr_root;
1660 			vref(root);
1661 		}
1662 		strlcpy(pr->pr_hostuuid, DEFAULT_HOSTUUID, HOSTUUIDLEN);
1663 		pr->pr_flags |= PR_HOST;
1664 #if defined(INET) || defined(INET6)
1665 #ifdef VIMAGE
1666 		if (!(pr_flags & PR_VNET))
1667 #endif
1668 		{
1669 #ifdef INET
1670 			if (!(ch_flags & PR_IP4_USER))
1671 				pr->pr_flags |= PR_IP4 | PR_IP4_USER;
1672 			else if (!(pr_flags & PR_IP4_USER)) {
1673 				pr->pr_flags |= ppr->pr_flags & PR_IP4;
1674 				prison_ip_dup(ppr, pr, PR_INET);
1675 			}
1676 #endif
1677 #ifdef INET6
1678 			if (!(ch_flags & PR_IP6_USER))
1679 				pr->pr_flags |= PR_IP6 | PR_IP6_USER;
1680 			else if (!(pr_flags & PR_IP6_USER)) {
1681 				pr->pr_flags |= ppr->pr_flags & PR_IP6;
1682 				prison_ip_dup(ppr, pr, PR_INET6);
1683 			}
1684 #endif
1685 		}
1686 #endif
1687 		/* Source address selection is always on by default. */
1688 		pr->pr_flags |= _PR_IP_SADDRSEL;
1689 
1690 		pr->pr_securelevel = ppr->pr_securelevel;
1691 		pr->pr_allow = JAIL_DEFAULT_ALLOW & ppr->pr_allow;
1692 		pr->pr_enforce_statfs = jail_default_enforce_statfs;
1693 		pr->pr_devfs_rsnum = ppr->pr_devfs_rsnum;
1694 
1695 		pr->pr_osreldate = osreldt ? osreldt : ppr->pr_osreldate;
1696 		if (osrelstr == NULL)
1697 			strlcpy(pr->pr_osrelease, ppr->pr_osrelease,
1698 			    sizeof(pr->pr_osrelease));
1699 		else
1700 			strlcpy(pr->pr_osrelease, osrelstr,
1701 			    sizeof(pr->pr_osrelease));
1702 
1703 #ifdef VIMAGE
1704 		/*
1705 		 * Allocate a new vnet if specified.
1706 		 *
1707 		 * Set PR_VNET now if so, so that the vnet is disposed of
1708 		 * properly when the jail is destroyed.
1709 		 */
1710 		if (pr_flags & PR_VNET) {
1711 			pr->pr_flags |= PR_VNET;
1712 			pr->pr_vnet = vnet_alloc();
1713 		} else {
1714 			pr->pr_vnet = ppr->pr_vnet;
1715 		}
1716 #endif
1717 		/*
1718 		 * Allocate a dedicated cpuset for each jail.
1719 		 * Unlike other initial settings, this may return an error.
1720 		 */
1721 		error = cpuset_create_root(ppr, &pr->pr_cpuset);
1722 		if (error)
1723 			goto done_deref;
1724 
1725 		mtx_lock(&pr->pr_mtx);
1726 		drflags |= PD_LOCKED;
1727 	} else {
1728 		/*
1729 		 * Grab a reference for existing prisons, to ensure they
1730 		 * continue to exist for the duration of the call.
1731 		 */
1732 		prison_hold(pr);
1733 		drflags |= PD_DEREF;
1734 #if defined(VIMAGE) && (defined(INET) || defined(INET6))
1735 		if ((pr->pr_flags & PR_VNET) &&
1736 		    (ch_flags & (PR_IP4_USER | PR_IP6_USER))) {
1737 			error = EINVAL;
1738 			vfs_opterror(opts,
1739 			    "vnet jails cannot have IP address restrictions");
1740 			goto done_deref;
1741 		}
1742 #endif
1743 #ifdef INET
1744 		if (PR_IP4_USER & ch_flags & (pr_flags ^ pr->pr_flags)) {
1745 			error = EINVAL;
1746 			vfs_opterror(opts,
1747 			    "ip4 cannot be changed after creation");
1748 			goto done_deref;
1749 		}
1750 #endif
1751 #ifdef INET6
1752 		if (PR_IP6_USER & ch_flags & (pr_flags ^ pr->pr_flags)) {
1753 			error = EINVAL;
1754 			vfs_opterror(opts,
1755 			    "ip6 cannot be changed after creation");
1756 			goto done_deref;
1757 		}
1758 #endif
1759 	}
1760 
1761 	/* Do final error checking before setting anything. */
1762 	if (gotslevel) {
1763 		if (slevel < ppr->pr_securelevel) {
1764 			error = EPERM;
1765 			goto done_deref;
1766 		}
1767 	}
1768 	if (gotchildmax) {
1769 		if (childmax >= ppr->pr_childmax) {
1770 			error = EPERM;
1771 			goto done_deref;
1772 		}
1773 	}
1774 	if (gotenforce) {
1775 		if (enforce < ppr->pr_enforce_statfs) {
1776 			error = EPERM;
1777 			goto done_deref;
1778 		}
1779 	}
1780 	if (gotrsnum) {
1781 		/*
1782 		 * devfs_rsnum is a uint16_t
1783 		 */
1784 		if (rsnum < 0 || rsnum > 65535) {
1785 			error = EINVAL;
1786 			goto done_deref;
1787 		}
1788 		/*
1789 		 * Nested jails always inherit parent's devfs ruleset
1790 		 */
1791 		if (jailed(td->td_ucred)) {
1792 			if (rsnum > 0 && rsnum != ppr->pr_devfs_rsnum) {
1793 				error = EPERM;
1794 				goto done_deref;
1795 			} else
1796 				rsnum = ppr->pr_devfs_rsnum;
1797 		}
1798 	}
1799 #ifdef INET
1800 	if (ip4s > 0) {
1801 		if ((ppr->pr_flags & PR_IP4) &&
1802 		    !prison_ip_parent_match(ppr->pr_addrs[PR_INET], ip4,
1803 		    PR_INET)) {
1804 			error = EPERM;
1805 			goto done_deref;
1806 		}
1807 		if (!prison_ip_conflict_check(ppr, pr, ip4, PR_INET)) {
1808 			error = EADDRINUSE;
1809 			vfs_opterror(opts, "IPv4 addresses clash");
1810 			goto done_deref;
1811 		}
1812 	}
1813 #endif
1814 #ifdef INET6
1815 	if (ip6s > 0) {
1816 		if ((ppr->pr_flags & PR_IP6) &&
1817 		    !prison_ip_parent_match(ppr->pr_addrs[PR_INET6], ip6,
1818 		    PR_INET6)) {
1819 			error = EPERM;
1820 			goto done_deref;
1821 		}
1822 		if (!prison_ip_conflict_check(ppr, pr, ip6, PR_INET6)) {
1823 			error = EADDRINUSE;
1824 			vfs_opterror(opts, "IPv6 addresses clash");
1825 			goto done_deref;
1826 		}
1827 	}
1828 #endif
1829 	onamelen = namelen = 0;
1830 	if (namelc != NULL) {
1831 		/* Give a default name of the jid.  Also allow the name to be
1832 		 * explicitly the jid - but not any other number, and only in
1833 		 * normal form (no leading zero/etc).
1834 		 */
1835 		if (namelc[0] == '\0')
1836 			snprintf(namelc = numbuf, sizeof(numbuf), "%d", jid);
1837 		else if ((strtoul(namelc, &p, 10) != jid ||
1838 			  namelc[0] < '1' || namelc[0] > '9') && *p == '\0') {
1839 			error = EINVAL;
1840 			vfs_opterror(opts,
1841 			    "name cannot be numeric (unless it is the jid)");
1842 			goto done_deref;
1843 		}
1844 		/*
1845 		 * Make sure the name isn't too long for the prison or its
1846 		 * children.
1847 		 */
1848 		pnamelen = (ppr == &prison0) ? 0 : strlen(ppr->pr_name) + 1;
1849 		onamelen = strlen(pr->pr_name + pnamelen);
1850 		namelen = strlen(namelc);
1851 		if (pnamelen + namelen + 1 > sizeof(pr->pr_name)) {
1852 			error = ENAMETOOLONG;
1853 			goto done_deref;
1854 		}
1855 		FOREACH_PRISON_DESCENDANT(pr, tpr, descend) {
1856 			if (strlen(tpr->pr_name) + (namelen - onamelen) >=
1857 			    sizeof(pr->pr_name)) {
1858 				error = ENAMETOOLONG;
1859 				goto done_deref;
1860 			}
1861 		}
1862 	}
1863 	pr_allow_diff = pr_allow & ~ppr->pr_allow;
1864 	if (pr_allow_diff & ~PR_ALLOW_DIFFERENCES) {
1865 		error = EPERM;
1866 		goto done_deref;
1867 	}
1868 
1869 	/*
1870 	 * Let modules check their parameters.  This requires unlocking and
1871 	 * then re-locking the prison, but this is still a valid state as long
1872 	 * as allprison_lock remains xlocked.
1873 	 */
1874 	mtx_unlock(&pr->pr_mtx);
1875 	drflags &= ~PD_LOCKED;
1876 	error = osd_jail_call(pr, PR_METHOD_CHECK, opts);
1877 	if (error != 0)
1878 		goto done_deref;
1879 	mtx_lock(&pr->pr_mtx);
1880 	drflags |= PD_LOCKED;
1881 
1882 	/* At this point, all valid parameters should have been noted. */
1883 	TAILQ_FOREACH(opt, opts, link) {
1884 		if (!opt->seen && strcmp(opt->name, "errmsg")) {
1885 			error = EINVAL;
1886 			vfs_opterror(opts, "unknown parameter: %s", opt->name);
1887 			goto done_deref;
1888 		}
1889 	}
1890 
1891 	/* Set the parameters of the prison. */
1892 #ifdef INET
1893 	redo_ip4 = false;
1894 	if (pr_flags & PR_IP4_USER) {
1895 		pr->pr_flags |= PR_IP4;
1896 		prison_ip_set(pr, PR_INET, ip4);
1897 		ip4 = NULL;
1898 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
1899 #ifdef VIMAGE
1900 			if (tpr->pr_flags & PR_VNET) {
1901 				descend = 0;
1902 				continue;
1903 			}
1904 #endif
1905 			if (!prison_ip_restrict(tpr, PR_INET, NULL)) {
1906 				redo_ip4 = true;
1907 				descend = 0;
1908 			}
1909 		}
1910 	}
1911 #endif
1912 #ifdef INET6
1913 	redo_ip6 = false;
1914 	if (pr_flags & PR_IP6_USER) {
1915 		pr->pr_flags |= PR_IP6;
1916 		prison_ip_set(pr, PR_INET6, ip6);
1917 		ip6 = NULL;
1918 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
1919 #ifdef VIMAGE
1920 			if (tpr->pr_flags & PR_VNET) {
1921 				descend = 0;
1922 				continue;
1923 			}
1924 #endif
1925 			if (!prison_ip_restrict(tpr, PR_INET6, NULL)) {
1926 				redo_ip6 = true;
1927 				descend = 0;
1928 			}
1929 		}
1930 	}
1931 #endif
1932 	if (gotslevel) {
1933 		pr->pr_securelevel = slevel;
1934 		/* Set all child jails to be at least this level. */
1935 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend)
1936 			if (tpr->pr_securelevel < slevel)
1937 				tpr->pr_securelevel = slevel;
1938 	}
1939 	if (gotchildmax) {
1940 		pr->pr_childmax = childmax;
1941 		/* Set all child jails to under this limit. */
1942 		FOREACH_PRISON_DESCENDANT_LOCKED_LEVEL(pr, tpr, descend, level)
1943 			if (tpr->pr_childmax > childmax - level)
1944 				tpr->pr_childmax = childmax > level
1945 				    ? childmax - level : 0;
1946 	}
1947 	if (gotenforce) {
1948 		pr->pr_enforce_statfs = enforce;
1949 		/* Pass this restriction on to the children. */
1950 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend)
1951 			if (tpr->pr_enforce_statfs < enforce)
1952 				tpr->pr_enforce_statfs = enforce;
1953 	}
1954 	if (gotrsnum) {
1955 		pr->pr_devfs_rsnum = rsnum;
1956 		/* Pass this restriction on to the children. */
1957 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend)
1958 			tpr->pr_devfs_rsnum = rsnum;
1959 	}
1960 	if (namelc != NULL) {
1961 		if (ppr == &prison0)
1962 			strlcpy(pr->pr_name, namelc, sizeof(pr->pr_name));
1963 		else
1964 			snprintf(pr->pr_name, sizeof(pr->pr_name), "%s.%s",
1965 			    ppr->pr_name, namelc);
1966 		/* Change this component of child names. */
1967 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
1968 			bcopy(tpr->pr_name + onamelen, tpr->pr_name + namelen,
1969 			    strlen(tpr->pr_name + onamelen) + 1);
1970 			bcopy(pr->pr_name, tpr->pr_name, namelen);
1971 		}
1972 	}
1973 	if (path != NULL) {
1974 		/* Try to keep a real-rooted full pathname. */
1975 		strlcpy(pr->pr_path, path, sizeof(pr->pr_path));
1976 		pr->pr_root = root;
1977 		root = NULL;
1978 	}
1979 	if (PR_HOST & ch_flags & ~pr_flags) {
1980 		if (pr->pr_flags & PR_HOST) {
1981 			/*
1982 			 * Copy the parent's host info.  As with pr_ip4 above,
1983 			 * the lack of a lock on the parent is not a problem;
1984 			 * it is always set with allprison_lock at least
1985 			 * shared, and is held exclusively here.
1986 			 */
1987 			strlcpy(pr->pr_hostname, pr->pr_parent->pr_hostname,
1988 			    sizeof(pr->pr_hostname));
1989 			strlcpy(pr->pr_domainname, pr->pr_parent->pr_domainname,
1990 			    sizeof(pr->pr_domainname));
1991 			strlcpy(pr->pr_hostuuid, pr->pr_parent->pr_hostuuid,
1992 			    sizeof(pr->pr_hostuuid));
1993 			pr->pr_hostid = pr->pr_parent->pr_hostid;
1994 		}
1995 	} else if (host != NULL || domain != NULL || uuid != NULL || gothid) {
1996 		/* Set this prison, and any descendants without PR_HOST. */
1997 		if (host != NULL)
1998 			strlcpy(pr->pr_hostname, host, sizeof(pr->pr_hostname));
1999 		if (domain != NULL)
2000 			strlcpy(pr->pr_domainname, domain,
2001 			    sizeof(pr->pr_domainname));
2002 		if (uuid != NULL)
2003 			strlcpy(pr->pr_hostuuid, uuid, sizeof(pr->pr_hostuuid));
2004 		if (gothid)
2005 			pr->pr_hostid = hid;
2006 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
2007 			if (tpr->pr_flags & PR_HOST)
2008 				descend = 0;
2009 			else {
2010 				if (host != NULL)
2011 					strlcpy(tpr->pr_hostname,
2012 					    pr->pr_hostname,
2013 					    sizeof(tpr->pr_hostname));
2014 				if (domain != NULL)
2015 					strlcpy(tpr->pr_domainname,
2016 					    pr->pr_domainname,
2017 					    sizeof(tpr->pr_domainname));
2018 				if (uuid != NULL)
2019 					strlcpy(tpr->pr_hostuuid,
2020 					    pr->pr_hostuuid,
2021 					    sizeof(tpr->pr_hostuuid));
2022 				if (gothid)
2023 					tpr->pr_hostid = hid;
2024 			}
2025 		}
2026 	}
2027 	pr->pr_allow = (pr->pr_allow & ~ch_allow) | pr_allow;
2028 	if ((tallow = ch_allow & ~pr_allow))
2029 		prison_set_allow_locked(pr, tallow, 0);
2030 	/*
2031 	 * Persistent prisons get an extra reference, and prisons losing their
2032 	 * persist flag lose that reference.
2033 	 */
2034 	born = !prison_isalive(pr);
2035 	if (ch_flags & PR_PERSIST & (pr_flags ^ pr->pr_flags)) {
2036 		if (pr_flags & PR_PERSIST) {
2037 			prison_hold(pr);
2038 			/*
2039 			 * This may make a dead prison alive again, but wait
2040 			 * to label it as such until after OSD calls have had
2041 			 * a chance to run (and perhaps to fail).
2042 			 */
2043 			refcount_acquire(&pr->pr_uref);
2044 		} else {
2045 			drflags |= PD_DEUREF;
2046 			prison_free_not_last(pr);
2047 		}
2048 	}
2049 	pr->pr_flags = (pr->pr_flags & ~ch_flags) | pr_flags;
2050 	mtx_unlock(&pr->pr_mtx);
2051 	drflags &= ~PD_LOCKED;
2052 	/*
2053 	 * Any errors past this point will need to de-persist newly created
2054 	 * prisons, as well as call remove methods.
2055 	 */
2056 	if (born)
2057 		drflags |= PD_KILL;
2058 
2059 #ifdef RACCT
2060 	if (racct_enable && created)
2061 		prison_racct_attach(pr);
2062 #endif
2063 
2064 	/* Locks may have prevented a complete restriction of child IP
2065 	 * addresses.  If so, allocate some more memory and try again.
2066 	 */
2067 #ifdef INET
2068 	while (redo_ip4) {
2069 		ip4s = pr->pr_addrs[PR_INET]->ips;
2070 		MPASS(ip4 == NULL);
2071 		ip4 = prison_ip_alloc(PR_INET, ip4s, M_WAITOK);
2072 		mtx_lock(&pr->pr_mtx);
2073 		redo_ip4 = false;
2074 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
2075 #ifdef VIMAGE
2076 			if (tpr->pr_flags & PR_VNET) {
2077 				descend = 0;
2078 				continue;
2079 			}
2080 #endif
2081 			if (!prison_ip_restrict(tpr, PR_INET, &ip4))
2082 				redo_ip4 = true;
2083 		}
2084 		mtx_unlock(&pr->pr_mtx);
2085 	}
2086 #endif
2087 #ifdef INET6
2088 	while (redo_ip6) {
2089 		ip6s = pr->pr_addrs[PR_INET6]->ips;
2090 		MPASS(ip6 == NULL);
2091 		ip6 = prison_ip_alloc(PR_INET6, ip6s, M_WAITOK);
2092 		mtx_lock(&pr->pr_mtx);
2093 		redo_ip6 = false;
2094 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
2095 #ifdef VIMAGE
2096 			if (tpr->pr_flags & PR_VNET) {
2097 				descend = 0;
2098 				continue;
2099 			}
2100 #endif
2101 			if (!prison_ip_restrict(tpr, PR_INET6, &ip6))
2102 				redo_ip6 = true;
2103 		}
2104 		mtx_unlock(&pr->pr_mtx);
2105 	}
2106 #endif
2107 
2108 	/* Let the modules do their work. */
2109 	if (born) {
2110 		error = osd_jail_call(pr, PR_METHOD_CREATE, opts);
2111 		if (error)
2112 			goto done_deref;
2113 	}
2114 	error = osd_jail_call(pr, PR_METHOD_SET, opts);
2115 	if (error)
2116 		goto done_deref;
2117 
2118 	/*
2119 	 * A new prison is now ready to be seen; either it has gained a user
2120 	 * reference via persistence, or is about to gain one via attachment.
2121 	 */
2122 	if (born) {
2123 		drflags = prison_lock_xlock(pr, drflags);
2124 		pr->pr_state = PRISON_STATE_ALIVE;
2125 	}
2126 
2127 	/* Attach this process to the prison if requested. */
2128 	if (flags & JAIL_ATTACH) {
2129 		error = do_jail_attach(td, pr,
2130 		    prison_lock_xlock(pr, drflags & PD_LOCK_FLAGS));
2131 		drflags &= ~(PD_LOCKED | PD_LIST_XLOCKED);
2132 		if (error) {
2133 			vfs_opterror(opts, "attach failed");
2134 			goto done_deref;
2135 		}
2136 	}
2137 
2138 #ifdef RACCT
2139 	if (racct_enable && !created) {
2140 		if (drflags & PD_LOCKED) {
2141 			mtx_unlock(&pr->pr_mtx);
2142 			drflags &= ~PD_LOCKED;
2143 		}
2144 		if (drflags & PD_LIST_XLOCKED) {
2145 			sx_xunlock(&allprison_lock);
2146 			drflags &= ~PD_LIST_XLOCKED;
2147 		}
2148 		prison_racct_modify(pr);
2149 	}
2150 #endif
2151 
2152 	if (born && pr != &prison0 && (pr->pr_allow & PR_ALLOW_NFSD) != 0 &&
2153 	    (pr->pr_root->v_vflag & VV_ROOT) == 0)
2154 		printf("Warning jail jid=%d: mountd/nfsd requires a separate"
2155 		   " file system\n", pr->pr_id);
2156 
2157 	drflags &= ~PD_KILL;
2158 	td->td_retval[0] = pr->pr_id;
2159 
2160  done_deref:
2161 	/* Release any temporary prison holds and/or locks. */
2162 	if (pr != NULL)
2163 		prison_deref(pr, drflags);
2164 	else if (drflags & PD_LIST_SLOCKED)
2165 		sx_sunlock(&allprison_lock);
2166 	else if (drflags & PD_LIST_XLOCKED)
2167 		sx_xunlock(&allprison_lock);
2168 	if (root != NULL)
2169 		vrele(root);
2170  done_errmsg:
2171 	if (error) {
2172 		/* Write the error message back to userspace. */
2173 		if (vfs_getopt(opts, "errmsg", (void **)&errmsg,
2174 		    &errmsg_len) == 0 && errmsg_len > 0) {
2175 			errmsg_pos = 2 * vfs_getopt_pos(opts, "errmsg") + 1;
2176 			if (optuio->uio_segflg == UIO_SYSSPACE)
2177 				bcopy(errmsg,
2178 				    optuio->uio_iov[errmsg_pos].iov_base,
2179 				    errmsg_len);
2180 			else
2181 				(void)copyout(errmsg,
2182 				    optuio->uio_iov[errmsg_pos].iov_base,
2183 				    errmsg_len);
2184 		}
2185 	}
2186  done_free:
2187 #ifdef INET
2188 	prison_ip_free(ip4);
2189 #endif
2190 #ifdef INET6
2191 	prison_ip_free(ip6);
2192 #endif
2193 	if (g_path != NULL)
2194 		free(g_path, M_TEMP);
2195 	vfs_freeopts(opts);
2196 	return (error);
2197 }
2198 
2199 /*
2200  * Find the next available prison ID.  Return the ID on success, or zero
2201  * on failure.  Also set a pointer to the allprison list entry the prison
2202  * should be inserted before.
2203  */
2204 static int
get_next_prid(struct prison ** insprp)2205 get_next_prid(struct prison **insprp)
2206 {
2207 	struct prison *inspr;
2208 	int jid, maxid;
2209 
2210 	jid = lastprid % JAIL_MAX + 1;
2211 	if (TAILQ_EMPTY(&allprison) ||
2212 	    TAILQ_LAST(&allprison, prisonlist)->pr_id < jid) {
2213 		/*
2214 		 * A common case is for all jails to be implicitly numbered,
2215 		 * which means they'll go on the end of the list, at least
2216 		 * for the first JAIL_MAX times.
2217 		 */
2218 		inspr = NULL;
2219 	} else {
2220 		/*
2221 		 * Take two passes through the allprison list: first starting
2222 		 * with the proposed jid, then ending with it.
2223 		 */
2224 		for (maxid = JAIL_MAX; maxid != 0; ) {
2225 			TAILQ_FOREACH(inspr, &allprison, pr_list) {
2226 				if (inspr->pr_id < jid)
2227 					continue;
2228 				if (inspr->pr_id > jid) {
2229 					/* Found an opening. */
2230 					maxid = 0;
2231 					break;
2232 				}
2233 				if (++jid > maxid) {
2234 					if (lastprid == maxid || lastprid == 0)
2235 					{
2236 						/*
2237 						 * The entire legal range
2238 						 * has been traversed
2239 						 */
2240 						return 0;
2241 					}
2242 					/* Try again from the start. */
2243 					jid = 1;
2244 					maxid = lastprid;
2245 					break;
2246 				}
2247 			}
2248 			if (inspr == NULL) {
2249 				/* Found room at the end of the list. */
2250 				break;
2251 			}
2252 		}
2253 	}
2254 	*insprp = inspr;
2255 	lastprid = jid;
2256 	return (jid);
2257 }
2258 
2259 /*
2260  * struct jail_get_args {
2261  *	struct iovec *iovp;
2262  *	unsigned int iovcnt;
2263  *	int flags;
2264  * };
2265  */
2266 int
sys_jail_get(struct thread * td,struct jail_get_args * uap)2267 sys_jail_get(struct thread *td, struct jail_get_args *uap)
2268 {
2269 	struct uio *auio;
2270 	int error;
2271 
2272 	/* Check that we have an even number of iovecs. */
2273 	if (uap->iovcnt & 1)
2274 		return (EINVAL);
2275 
2276 	error = copyinuio(uap->iovp, uap->iovcnt, &auio);
2277 	if (error)
2278 		return (error);
2279 	error = kern_jail_get(td, auio, uap->flags);
2280 	if (error == 0)
2281 		error = copyout(auio->uio_iov, uap->iovp,
2282 		    uap->iovcnt * sizeof(struct iovec));
2283 	freeuio(auio);
2284 	return (error);
2285 }
2286 
2287 int
kern_jail_get(struct thread * td,struct uio * optuio,int flags)2288 kern_jail_get(struct thread *td, struct uio *optuio, int flags)
2289 {
2290 	struct bool_flags *bf;
2291 	struct jailsys_flags *jsf;
2292 	struct prison *pr, *mypr;
2293 	struct vfsopt *opt;
2294 	struct vfsoptlist *opts;
2295 	char *errmsg, *name;
2296 	int drflags, error, errmsg_len, errmsg_pos, i, jid, len, pos;
2297 	unsigned f;
2298 
2299 	if (flags & ~JAIL_GET_MASK)
2300 		return (EINVAL);
2301 
2302 	/* Get the parameter list. */
2303 	error = vfs_buildopts(optuio, &opts);
2304 	if (error)
2305 		return (error);
2306 	errmsg_pos = vfs_getopt_pos(opts, "errmsg");
2307 	mypr = td->td_ucred->cr_prison;
2308 	pr = NULL;
2309 
2310 	/*
2311 	 * Find the prison specified by one of: lastjid, jid, name.
2312 	 */
2313 	sx_slock(&allprison_lock);
2314 	drflags = PD_LIST_SLOCKED;
2315 	error = vfs_copyopt(opts, "lastjid", &jid, sizeof(jid));
2316 	if (error == 0) {
2317 		TAILQ_FOREACH(pr, &allprison, pr_list) {
2318 			if (pr->pr_id > jid &&
2319 			    ((flags & JAIL_DYING) || prison_isalive(pr)) &&
2320 			    prison_ischild(mypr, pr)) {
2321 				mtx_lock(&pr->pr_mtx);
2322 				drflags |= PD_LOCKED;
2323 				goto found_prison;
2324 			}
2325 		}
2326 		error = ENOENT;
2327 		vfs_opterror(opts, "no jail after %d", jid);
2328 		goto done;
2329 	} else if (error != ENOENT)
2330 		goto done;
2331 
2332 	error = vfs_copyopt(opts, "jid", &jid, sizeof(jid));
2333 	if (error == 0) {
2334 		if (jid != 0) {
2335 			pr = prison_find_child(mypr, jid);
2336 			if (pr != NULL) {
2337 				drflags |= PD_LOCKED;
2338 				if (!(prison_isalive(pr) ||
2339 				    (flags & JAIL_DYING))) {
2340 					error = ENOENT;
2341 					vfs_opterror(opts, "jail %d is dying",
2342 					    jid);
2343 					goto done;
2344 				}
2345 				goto found_prison;
2346 			}
2347 			error = ENOENT;
2348 			vfs_opterror(opts, "jail %d not found", jid);
2349 			goto done;
2350 		}
2351 	} else if (error != ENOENT)
2352 		goto done;
2353 
2354 	error = vfs_getopt(opts, "name", (void **)&name, &len);
2355 	if (error == 0) {
2356 		if (len == 0 || name[len - 1] != '\0') {
2357 			error = EINVAL;
2358 			goto done;
2359 		}
2360 		pr = prison_find_name(mypr, name);
2361 		if (pr != NULL) {
2362 			drflags |= PD_LOCKED;
2363 			if (!(prison_isalive(pr) || (flags & JAIL_DYING))) {
2364 				error = ENOENT;
2365 				vfs_opterror(opts, "jail \"%s\" is dying",
2366 				    name);
2367 				goto done;
2368 			}
2369 			goto found_prison;
2370 		}
2371 		error = ENOENT;
2372 		vfs_opterror(opts, "jail \"%s\" not found", name);
2373 		goto done;
2374 	} else if (error != ENOENT)
2375 		goto done;
2376 
2377 	vfs_opterror(opts, "no jail specified");
2378 	error = ENOENT;
2379 	goto done;
2380 
2381  found_prison:
2382 	/* Get the parameters of the prison. */
2383 	prison_hold(pr);
2384 	drflags |= PD_DEREF;
2385 	td->td_retval[0] = pr->pr_id;
2386 	error = vfs_setopt(opts, "jid", &pr->pr_id, sizeof(pr->pr_id));
2387 	if (error != 0 && error != ENOENT)
2388 		goto done;
2389 	i = (pr->pr_parent == mypr) ? 0 : pr->pr_parent->pr_id;
2390 	error = vfs_setopt(opts, "parent", &i, sizeof(i));
2391 	if (error != 0 && error != ENOENT)
2392 		goto done;
2393 	error = vfs_setopts(opts, "name", prison_name(mypr, pr));
2394 	if (error != 0 && error != ENOENT)
2395 		goto done;
2396 	error = vfs_setopt(opts, "cpuset.id", &pr->pr_cpuset->cs_id,
2397 	    sizeof(pr->pr_cpuset->cs_id));
2398 	if (error != 0 && error != ENOENT)
2399 		goto done;
2400 	error = vfs_setopts(opts, "path", prison_path(mypr, pr));
2401 	if (error != 0 && error != ENOENT)
2402 		goto done;
2403 #ifdef INET
2404 	error = vfs_setopt_part(opts, "ip4.addr", pr->pr_addrs[PR_INET]->pr_ip,
2405 	    pr->pr_addrs[PR_INET] ? pr->pr_addrs[PR_INET]->ips *
2406 	    pr_families[PR_INET].size : 0 );
2407 	if (error != 0 && error != ENOENT)
2408 		goto done;
2409 #endif
2410 #ifdef INET6
2411 	error = vfs_setopt_part(opts, "ip6.addr", pr->pr_addrs[PR_INET6]->pr_ip,
2412 	    pr->pr_addrs[PR_INET6] ? pr->pr_addrs[PR_INET6]->ips *
2413 	    pr_families[PR_INET6].size : 0 );
2414 	if (error != 0 && error != ENOENT)
2415 		goto done;
2416 #endif
2417 	error = vfs_setopt(opts, "securelevel", &pr->pr_securelevel,
2418 	    sizeof(pr->pr_securelevel));
2419 	if (error != 0 && error != ENOENT)
2420 		goto done;
2421 	error = vfs_setopt(opts, "children.cur", &pr->pr_childcount,
2422 	    sizeof(pr->pr_childcount));
2423 	if (error != 0 && error != ENOENT)
2424 		goto done;
2425 	error = vfs_setopt(opts, "children.max", &pr->pr_childmax,
2426 	    sizeof(pr->pr_childmax));
2427 	if (error != 0 && error != ENOENT)
2428 		goto done;
2429 	error = vfs_setopts(opts, "host.hostname", pr->pr_hostname);
2430 	if (error != 0 && error != ENOENT)
2431 		goto done;
2432 	error = vfs_setopts(opts, "host.domainname", pr->pr_domainname);
2433 	if (error != 0 && error != ENOENT)
2434 		goto done;
2435 	error = vfs_setopts(opts, "host.hostuuid", pr->pr_hostuuid);
2436 	if (error != 0 && error != ENOENT)
2437 		goto done;
2438 #ifdef COMPAT_FREEBSD32
2439 	if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
2440 		uint32_t hid32 = pr->pr_hostid;
2441 
2442 		error = vfs_setopt(opts, "host.hostid", &hid32, sizeof(hid32));
2443 	} else
2444 #endif
2445 	error = vfs_setopt(opts, "host.hostid", &pr->pr_hostid,
2446 	    sizeof(pr->pr_hostid));
2447 	if (error != 0 && error != ENOENT)
2448 		goto done;
2449 	error = vfs_setopt(opts, "enforce_statfs", &pr->pr_enforce_statfs,
2450 	    sizeof(pr->pr_enforce_statfs));
2451 	if (error != 0 && error != ENOENT)
2452 		goto done;
2453 	error = vfs_setopt(opts, "devfs_ruleset", &pr->pr_devfs_rsnum,
2454 	    sizeof(pr->pr_devfs_rsnum));
2455 	if (error != 0 && error != ENOENT)
2456 		goto done;
2457 	for (bf = pr_flag_bool;
2458 	     bf < pr_flag_bool + nitems(pr_flag_bool);
2459 	     bf++) {
2460 		i = (pr->pr_flags & bf->flag) ? 1 : 0;
2461 		error = vfs_setopt(opts, bf->name, &i, sizeof(i));
2462 		if (error != 0 && error != ENOENT)
2463 			goto done;
2464 		i = !i;
2465 		error = vfs_setopt(opts, bf->noname, &i, sizeof(i));
2466 		if (error != 0 && error != ENOENT)
2467 			goto done;
2468 	}
2469 	for (jsf = pr_flag_jailsys;
2470 	     jsf < pr_flag_jailsys + nitems(pr_flag_jailsys);
2471 	     jsf++) {
2472 		f = pr->pr_flags & (jsf->disable | jsf->new);
2473 		i = (f != 0 && f == jsf->disable) ? JAIL_SYS_DISABLE
2474 		    : (f == jsf->new) ? JAIL_SYS_NEW
2475 		    : JAIL_SYS_INHERIT;
2476 		error = vfs_setopt(opts, jsf->name, &i, sizeof(i));
2477 		if (error != 0 && error != ENOENT)
2478 			goto done;
2479 	}
2480 	for (bf = pr_flag_allow;
2481 	     bf < pr_flag_allow + nitems(pr_flag_allow) &&
2482 		atomic_load_int(&bf->flag) != 0;
2483 	     bf++) {
2484 		i = (pr->pr_allow & bf->flag) ? 1 : 0;
2485 		error = vfs_setopt(opts, bf->name, &i, sizeof(i));
2486 		if (error != 0 && error != ENOENT)
2487 			goto done;
2488 		i = !i;
2489 		error = vfs_setopt(opts, bf->noname, &i, sizeof(i));
2490 		if (error != 0 && error != ENOENT)
2491 			goto done;
2492 	}
2493 	i = !prison_isalive(pr);
2494 	error = vfs_setopt(opts, "dying", &i, sizeof(i));
2495 	if (error != 0 && error != ENOENT)
2496 		goto done;
2497 	i = !i;
2498 	error = vfs_setopt(opts, "nodying", &i, sizeof(i));
2499 	if (error != 0 && error != ENOENT)
2500 		goto done;
2501 	error = vfs_setopt(opts, "osreldate", &pr->pr_osreldate,
2502 	    sizeof(pr->pr_osreldate));
2503 	if (error != 0 && error != ENOENT)
2504 		goto done;
2505 	error = vfs_setopts(opts, "osrelease", pr->pr_osrelease);
2506 	if (error != 0 && error != ENOENT)
2507 		goto done;
2508 
2509 	/* Get the module parameters. */
2510 	mtx_unlock(&pr->pr_mtx);
2511 	drflags &= ~PD_LOCKED;
2512 	error = osd_jail_call(pr, PR_METHOD_GET, opts);
2513 	if (error)
2514 		goto done;
2515 	prison_deref(pr, drflags);
2516 	pr = NULL;
2517 	drflags = 0;
2518 
2519 	/* By now, all parameters should have been noted. */
2520 	TAILQ_FOREACH(opt, opts, link) {
2521 		if (!opt->seen && strcmp(opt->name, "errmsg")) {
2522 			error = EINVAL;
2523 			vfs_opterror(opts, "unknown parameter: %s", opt->name);
2524 			goto done;
2525 		}
2526 	}
2527 
2528 	/* Write the fetched parameters back to userspace. */
2529 	error = 0;
2530 	TAILQ_FOREACH(opt, opts, link) {
2531 		if (opt->pos >= 0 && opt->pos != errmsg_pos) {
2532 			pos = 2 * opt->pos + 1;
2533 			optuio->uio_iov[pos].iov_len = opt->len;
2534 			if (opt->value != NULL) {
2535 				if (optuio->uio_segflg == UIO_SYSSPACE) {
2536 					bcopy(opt->value,
2537 					    optuio->uio_iov[pos].iov_base,
2538 					    opt->len);
2539 				} else {
2540 					error = copyout(opt->value,
2541 					    optuio->uio_iov[pos].iov_base,
2542 					    opt->len);
2543 					if (error)
2544 						break;
2545 				}
2546 			}
2547 		}
2548 	}
2549 
2550  done:
2551 	/* Release any temporary prison holds and/or locks. */
2552 	if (pr != NULL)
2553 		prison_deref(pr, drflags);
2554 	else if (drflags & PD_LIST_SLOCKED)
2555 		sx_sunlock(&allprison_lock);
2556 	if (error && errmsg_pos >= 0) {
2557 		/* Write the error message back to userspace. */
2558 		vfs_getopt(opts, "errmsg", (void **)&errmsg, &errmsg_len);
2559 		errmsg_pos = 2 * errmsg_pos + 1;
2560 		if (errmsg_len > 0) {
2561 			if (optuio->uio_segflg == UIO_SYSSPACE)
2562 				bcopy(errmsg,
2563 				    optuio->uio_iov[errmsg_pos].iov_base,
2564 				    errmsg_len);
2565 			else
2566 				(void)copyout(errmsg,
2567 				    optuio->uio_iov[errmsg_pos].iov_base,
2568 				    errmsg_len);
2569 		}
2570 	}
2571 	vfs_freeopts(opts);
2572 	return (error);
2573 }
2574 
2575 /*
2576  * struct jail_remove_args {
2577  *	int jid;
2578  * };
2579  */
2580 int
sys_jail_remove(struct thread * td,struct jail_remove_args * uap)2581 sys_jail_remove(struct thread *td, struct jail_remove_args *uap)
2582 {
2583 	struct prison *pr;
2584 	int error;
2585 
2586 	error = priv_check(td, PRIV_JAIL_REMOVE);
2587 	if (error)
2588 		return (error);
2589 
2590 	sx_xlock(&allprison_lock);
2591 	pr = prison_find_child(td->td_ucred->cr_prison, uap->jid);
2592 	if (pr == NULL) {
2593 		sx_xunlock(&allprison_lock);
2594 		return (EINVAL);
2595 	}
2596 	if (!prison_isalive(pr)) {
2597 		/* Silently ignore already-dying prisons. */
2598 		mtx_unlock(&pr->pr_mtx);
2599 		sx_xunlock(&allprison_lock);
2600 		return (0);
2601 	}
2602 	prison_deref(pr, PD_KILL | PD_LOCKED | PD_LIST_XLOCKED);
2603 	return (0);
2604 }
2605 
2606 /*
2607  * struct jail_attach_args {
2608  *	int jid;
2609  * };
2610  */
2611 int
sys_jail_attach(struct thread * td,struct jail_attach_args * uap)2612 sys_jail_attach(struct thread *td, struct jail_attach_args *uap)
2613 {
2614 	struct prison *pr;
2615 	int error;
2616 
2617 	error = priv_check(td, PRIV_JAIL_ATTACH);
2618 	if (error)
2619 		return (error);
2620 
2621 	sx_slock(&allprison_lock);
2622 	pr = prison_find_child(td->td_ucred->cr_prison, uap->jid);
2623 	if (pr == NULL) {
2624 		sx_sunlock(&allprison_lock);
2625 		return (EINVAL);
2626 	}
2627 
2628 	/* Do not allow a process to attach to a prison that is not alive. */
2629 	if (!prison_isalive(pr)) {
2630 		mtx_unlock(&pr->pr_mtx);
2631 		sx_sunlock(&allprison_lock);
2632 		return (EINVAL);
2633 	}
2634 
2635 	return (do_jail_attach(td, pr, PD_LOCKED | PD_LIST_SLOCKED));
2636 }
2637 
2638 static int
do_jail_attach(struct thread * td,struct prison * pr,int drflags)2639 do_jail_attach(struct thread *td, struct prison *pr, int drflags)
2640 {
2641 	struct proc *p;
2642 	struct ucred *newcred, *oldcred;
2643 	int error;
2644 
2645 	mtx_assert(&pr->pr_mtx, MA_OWNED);
2646 	sx_assert(&allprison_lock, SX_LOCKED);
2647 	drflags &= PD_LOCK_FLAGS;
2648 	/*
2649 	 * XXX: Note that there is a slight race here if two threads
2650 	 * in the same privileged process attempt to attach to two
2651 	 * different jails at the same time.  It is important for
2652 	 * user processes not to do this, or they might end up with
2653 	 * a process root from one prison, but attached to the jail
2654 	 * of another.
2655 	 */
2656 	prison_hold(pr);
2657 	refcount_acquire(&pr->pr_uref);
2658 	drflags |= PD_DEREF | PD_DEUREF;
2659 	mtx_unlock(&pr->pr_mtx);
2660 	drflags &= ~PD_LOCKED;
2661 
2662 	/* Let modules do whatever they need to prepare for attaching. */
2663 	error = osd_jail_call(pr, PR_METHOD_ATTACH, td);
2664 	if (error) {
2665 		prison_deref(pr, drflags);
2666 		return (error);
2667 	}
2668 	sx_unlock(&allprison_lock);
2669 	drflags &= ~(PD_LIST_SLOCKED | PD_LIST_XLOCKED);
2670 
2671 	/*
2672 	 * Reparent the newly attached process to this jail.
2673 	 */
2674 	p = td->td_proc;
2675 	error = cpuset_setproc_update_set(p, pr->pr_cpuset);
2676 	if (error)
2677 		goto e_revert_osd;
2678 
2679 	vn_lock(pr->pr_root, LK_EXCLUSIVE | LK_RETRY);
2680 	if ((error = change_dir(pr->pr_root, td)) != 0)
2681 		goto e_unlock;
2682 #ifdef MAC
2683 	if ((error = mac_vnode_check_chroot(td->td_ucred, pr->pr_root)))
2684 		goto e_unlock;
2685 #endif
2686 	VOP_UNLOCK(pr->pr_root);
2687 	if ((error = pwd_chroot_chdir(td, pr->pr_root)))
2688 		goto e_revert_osd;
2689 
2690 	newcred = crget();
2691 	PROC_LOCK(p);
2692 	oldcred = crcopysafe(p, newcred);
2693 	newcred->cr_prison = pr;
2694 	proc_set_cred(p, newcred);
2695 	setsugid(p);
2696 #ifdef RACCT
2697 	racct_proc_ucred_changed(p, oldcred, newcred);
2698 	crhold(newcred);
2699 #endif
2700 	PROC_UNLOCK(p);
2701 #ifdef RCTL
2702 	rctl_proc_ucred_changed(p, newcred);
2703 	crfree(newcred);
2704 #endif
2705 	prison_proc_relink(oldcred->cr_prison, pr, p);
2706 	prison_deref(oldcred->cr_prison, drflags);
2707 	crfree(oldcred);
2708 
2709 	/*
2710 	 * If the prison was killed while changing credentials, die along
2711 	 * with it.
2712 	 */
2713 	if (!prison_isalive(pr)) {
2714 		PROC_LOCK(p);
2715 		kern_psignal(p, SIGKILL);
2716 		PROC_UNLOCK(p);
2717 	}
2718 
2719 	return (0);
2720 
2721  e_unlock:
2722 	VOP_UNLOCK(pr->pr_root);
2723  e_revert_osd:
2724 	/* Tell modules this thread is still in its old jail after all. */
2725 	sx_slock(&allprison_lock);
2726 	drflags |= PD_LIST_SLOCKED;
2727 	(void)osd_jail_call(td->td_ucred->cr_prison, PR_METHOD_ATTACH, td);
2728 	prison_deref(pr, drflags);
2729 	return (error);
2730 }
2731 
2732 /*
2733  * Returns a locked prison instance, or NULL on failure.
2734  */
2735 struct prison *
prison_find(int prid)2736 prison_find(int prid)
2737 {
2738 	struct prison *pr;
2739 
2740 	sx_assert(&allprison_lock, SX_LOCKED);
2741 	TAILQ_FOREACH(pr, &allprison, pr_list) {
2742 		if (pr->pr_id < prid)
2743 			continue;
2744 		if (pr->pr_id > prid)
2745 			break;
2746 		KASSERT(prison_isvalid(pr), ("Found invalid prison %p", pr));
2747 		mtx_lock(&pr->pr_mtx);
2748 		return (pr);
2749 	}
2750 	return (NULL);
2751 }
2752 
2753 /*
2754  * Find a prison that is a descendant of mypr.  Returns a locked prison or NULL.
2755  */
2756 struct prison *
prison_find_child(struct prison * mypr,int prid)2757 prison_find_child(struct prison *mypr, int prid)
2758 {
2759 	struct prison *pr;
2760 	int descend;
2761 
2762 	sx_assert(&allprison_lock, SX_LOCKED);
2763 	FOREACH_PRISON_DESCENDANT(mypr, pr, descend) {
2764 		if (pr->pr_id == prid) {
2765 			KASSERT(prison_isvalid(pr),
2766 			    ("Found invalid prison %p", pr));
2767 			mtx_lock(&pr->pr_mtx);
2768 			return (pr);
2769 		}
2770 	}
2771 	return (NULL);
2772 }
2773 
2774 /*
2775  * Look for the name relative to mypr.  Returns a locked prison or NULL.
2776  */
2777 struct prison *
prison_find_name(struct prison * mypr,const char * name)2778 prison_find_name(struct prison *mypr, const char *name)
2779 {
2780 	struct prison *pr, *deadpr;
2781 	size_t mylen;
2782 	int descend;
2783 
2784 	sx_assert(&allprison_lock, SX_LOCKED);
2785 	mylen = (mypr == &prison0) ? 0 : strlen(mypr->pr_name) + 1;
2786 	deadpr = NULL;
2787 	FOREACH_PRISON_DESCENDANT(mypr, pr, descend) {
2788 		if (!strcmp(pr->pr_name + mylen, name)) {
2789 			KASSERT(prison_isvalid(pr),
2790 			    ("Found invalid prison %p", pr));
2791 			if (prison_isalive(pr)) {
2792 				mtx_lock(&pr->pr_mtx);
2793 				return (pr);
2794 			}
2795 			deadpr = pr;
2796 		}
2797 	}
2798 	/* There was no valid prison - perhaps there was a dying one. */
2799 	if (deadpr != NULL)
2800 		mtx_lock(&deadpr->pr_mtx);
2801 	return (deadpr);
2802 }
2803 
2804 /*
2805  * See if a prison has the specific flag set.  The prison should be locked,
2806  * unless checking for flags that are only set at jail creation (such as
2807  * PR_IP4 and PR_IP6), or only the single bit is examined, without regard
2808  * to any other prison data.
2809  */
2810 bool
prison_flag(struct ucred * cred,unsigned flag)2811 prison_flag(struct ucred *cred, unsigned flag)
2812 {
2813 
2814 	return ((cred->cr_prison->pr_flags & flag) != 0);
2815 }
2816 
2817 /*
2818  * See if a prison has the specific allow flag set.
2819  * The prison *should* be locked, or only a single bit is examined, without
2820  * regard to any other prison data.
2821  */
2822 bool
prison_allow(struct ucred * cred,unsigned flag)2823 prison_allow(struct ucred *cred, unsigned flag)
2824 {
2825 
2826 	return ((cred->cr_prison->pr_allow & flag) != 0);
2827 }
2828 
2829 /*
2830  * Hold a prison reference, by incrementing pr_ref.  It is generally
2831  * an error to hold a prison that does not already have a reference.
2832  * A prison record will remain valid as long as it has at least one
2833  * reference, and will not be removed as long as either the prison
2834  * mutex or the allprison lock is held (allprison_lock may be shared).
2835  */
2836 void
prison_hold_locked(struct prison * pr)2837 prison_hold_locked(struct prison *pr)
2838 {
2839 
2840 	/* Locking is no longer required. */
2841 	prison_hold(pr);
2842 }
2843 
2844 void
prison_hold(struct prison * pr)2845 prison_hold(struct prison *pr)
2846 {
2847 #ifdef INVARIANTS
2848 	int was_valid = refcount_acquire_if_not_zero(&pr->pr_ref);
2849 
2850 	KASSERT(was_valid,
2851 	    ("Trying to hold dead prison %p (jid=%d).", pr, pr->pr_id));
2852 #else
2853 	refcount_acquire(&pr->pr_ref);
2854 #endif
2855 }
2856 
2857 /*
2858  * Remove a prison reference.  If that was the last reference, the
2859  * prison will be removed (at a later time).
2860  */
2861 void
prison_free_locked(struct prison * pr)2862 prison_free_locked(struct prison *pr)
2863 {
2864 
2865 	mtx_assert(&pr->pr_mtx, MA_OWNED);
2866 	/*
2867 	 * Locking is no longer required, but unlock because the caller
2868 	 * expects it.
2869 	 */
2870 	mtx_unlock(&pr->pr_mtx);
2871 	prison_free(pr);
2872 }
2873 
2874 void
prison_free(struct prison * pr)2875 prison_free(struct prison *pr)
2876 {
2877 
2878 	KASSERT(refcount_load(&pr->pr_ref) > 0,
2879 	    ("Trying to free dead prison %p (jid=%d).",
2880 	     pr, pr->pr_id));
2881 	if (!refcount_release_if_not_last(&pr->pr_ref)) {
2882 		/*
2883 		 * Don't remove the last reference in this context,
2884 		 * in case there are locks held.
2885 		 */
2886 		taskqueue_enqueue(taskqueue_jail_remove, &pr->pr_task);
2887 	}
2888 }
2889 
2890 static void
prison_free_not_last(struct prison * pr)2891 prison_free_not_last(struct prison *pr)
2892 {
2893 #ifdef INVARIANTS
2894 	int lastref;
2895 
2896 	KASSERT(refcount_load(&pr->pr_ref) > 0,
2897 	    ("Trying to free dead prison %p (jid=%d).",
2898 	     pr, pr->pr_id));
2899 	lastref = refcount_release(&pr->pr_ref);
2900 	KASSERT(!lastref,
2901 	    ("prison_free_not_last freed last ref on prison %p (jid=%d).",
2902 	     pr, pr->pr_id));
2903 #else
2904 	refcount_release(&pr->pr_ref);
2905 #endif
2906 }
2907 
2908 /*
2909  * Hold a prison for user visibility, by incrementing pr_uref.
2910  * It is generally an error to hold a prison that isn't already
2911  * user-visible, except through the jail system calls.  It is also
2912  * an error to hold an invalid prison.  A prison record will remain
2913  * alive as long as it has at least one user reference, and will not
2914  * be set to the dying state until the prison mutex and allprison_lock
2915  * are both freed.
2916  */
2917 void
prison_proc_hold(struct prison * pr)2918 prison_proc_hold(struct prison *pr)
2919 {
2920 #ifdef INVARIANTS
2921 	int was_alive = refcount_acquire_if_not_zero(&pr->pr_uref);
2922 
2923 	KASSERT(was_alive,
2924 	    ("Cannot add a process to a non-alive prison (jid=%d)", pr->pr_id));
2925 #else
2926 	refcount_acquire(&pr->pr_uref);
2927 #endif
2928 }
2929 
2930 /*
2931  * Remove a prison user reference.  If it was the last reference, the
2932  * prison will be considered "dying", and may be removed once all of
2933  * its references are dropped.
2934  */
2935 void
prison_proc_free(struct prison * pr)2936 prison_proc_free(struct prison *pr)
2937 {
2938 
2939 	/*
2940 	 * Locking is only required when releasing the last reference.
2941 	 * This allows assurance that a locked prison will remain alive
2942 	 * until it is unlocked.
2943 	 */
2944 	KASSERT(refcount_load(&pr->pr_uref) > 0,
2945 	    ("Trying to kill a process in a dead prison (jid=%d)", pr->pr_id));
2946 	if (!refcount_release_if_not_last(&pr->pr_uref)) {
2947 		/*
2948 		 * Don't remove the last user reference in this context,
2949 		 * which is expected to be a process that is not only locked,
2950 		 * but also half dead.  Add a reference so any calls to
2951 		 * prison_free() won't re-submit the task.
2952 		 */
2953 		prison_hold(pr);
2954 		mtx_lock(&pr->pr_mtx);
2955 		KASSERT(!(pr->pr_flags & PR_COMPLETE_PROC),
2956 		    ("Redundant last reference in prison_proc_free (jid=%d)",
2957 		     pr->pr_id));
2958 		pr->pr_flags |= PR_COMPLETE_PROC;
2959 		mtx_unlock(&pr->pr_mtx);
2960 		taskqueue_enqueue(taskqueue_jail_remove, &pr->pr_task);
2961 	}
2962 }
2963 
2964 static void
prison_proc_free_not_last(struct prison * pr)2965 prison_proc_free_not_last(struct prison *pr)
2966 {
2967 #ifdef INVARIANTS
2968 	int lastref;
2969 
2970 	KASSERT(refcount_load(&pr->pr_uref) > 0,
2971 	    ("Trying to free dead prison %p (jid=%d).",
2972 	     pr, pr->pr_id));
2973 	lastref = refcount_release(&pr->pr_uref);
2974 	KASSERT(!lastref,
2975 	    ("prison_proc_free_not_last freed last uref on prison %p (jid=%d).",
2976 	     pr, pr->pr_id));
2977 #else
2978 	refcount_release(&pr->pr_uref);
2979 #endif
2980 }
2981 
2982 void
prison_proc_link(struct prison * pr,struct proc * p)2983 prison_proc_link(struct prison *pr, struct proc *p)
2984 {
2985 
2986 	sx_assert(&allproc_lock, SA_XLOCKED);
2987 	LIST_INSERT_HEAD(&pr->pr_proclist, p, p_jaillist);
2988 }
2989 
2990 void
prison_proc_unlink(struct prison * pr,struct proc * p)2991 prison_proc_unlink(struct prison *pr, struct proc *p)
2992 {
2993 
2994 	sx_assert(&allproc_lock, SA_XLOCKED);
2995 	LIST_REMOVE(p, p_jaillist);
2996 }
2997 
2998 static void
prison_proc_relink(struct prison * opr,struct prison * npr,struct proc * p)2999 prison_proc_relink(struct prison *opr, struct prison *npr, struct proc *p)
3000 {
3001 
3002 	sx_xlock(&allproc_lock);
3003 	prison_proc_unlink(opr, p);
3004 	prison_proc_link(npr, p);
3005 	sx_xunlock(&allproc_lock);
3006 }
3007 
3008 /*
3009  * Complete a call to either prison_free or prison_proc_free.
3010  */
3011 static void
prison_complete(void * context,int pending)3012 prison_complete(void *context, int pending)
3013 {
3014 	struct prison *pr = context;
3015 	int drflags;
3016 
3017 	/*
3018 	 * This could be called to release the last reference, or the last
3019 	 * user reference (plus the reference held in prison_proc_free).
3020 	 */
3021 	drflags = prison_lock_xlock(pr, PD_DEREF);
3022 	if (pr->pr_flags & PR_COMPLETE_PROC) {
3023 		pr->pr_flags &= ~PR_COMPLETE_PROC;
3024 		drflags |= PD_DEUREF;
3025 	}
3026 	prison_deref(pr, drflags);
3027 }
3028 
3029 static void
prison_kill_processes_cb(struct proc * p,void * arg __unused)3030 prison_kill_processes_cb(struct proc *p, void *arg __unused)
3031 {
3032 
3033 	kern_psignal(p, SIGKILL);
3034 }
3035 
3036 /*
3037  * Note the iteration does not guarantee acting on all processes.
3038  * Most notably there may be fork or jail_attach in progress.
3039  */
3040 void
prison_proc_iterate(struct prison * pr,void (* cb)(struct proc *,void *),void * cbarg)3041 prison_proc_iterate(struct prison *pr, void (*cb)(struct proc *, void *),
3042     void *cbarg)
3043 {
3044 	struct prison *ppr;
3045 	struct proc *p;
3046 
3047 	if (atomic_load_int(&pr->pr_childcount) == 0) {
3048 		sx_slock(&allproc_lock);
3049 		LIST_FOREACH(p, &pr->pr_proclist, p_jaillist) {
3050 			if (p->p_state == PRS_NEW)
3051 				continue;
3052 			PROC_LOCK(p);
3053 			cb(p, cbarg);
3054 			PROC_UNLOCK(p);
3055 		}
3056 		sx_sunlock(&allproc_lock);
3057 		if (atomic_load_int(&pr->pr_childcount) == 0)
3058 			return;
3059 		/*
3060 		 * Some jails popped up during the iteration, fall through to a
3061 		 * system-wide search.
3062 		 */
3063 	}
3064 
3065 	sx_slock(&allproc_lock);
3066 	FOREACH_PROC_IN_SYSTEM(p) {
3067 		PROC_LOCK(p);
3068 		if (p->p_state != PRS_NEW && p->p_ucred != NULL) {
3069 			for (ppr = p->p_ucred->cr_prison; ppr != NULL;
3070 			    ppr = ppr->pr_parent) {
3071 				if (ppr == pr) {
3072 					cb(p, cbarg);
3073 					break;
3074 				}
3075 			}
3076 		}
3077 		PROC_UNLOCK(p);
3078 	}
3079 	sx_sunlock(&allproc_lock);
3080 }
3081 
3082 /*
3083  * Remove a prison reference and/or user reference (usually).
3084  * This assumes context that allows sleeping (for allprison_lock),
3085  * with no non-sleeping locks held, except perhaps the prison itself.
3086  * If there are no more references, release and delist the prison.
3087  * On completion, the prison lock and the allprison lock are both
3088  * unlocked.
3089  */
3090 static void
prison_deref(struct prison * pr,int flags)3091 prison_deref(struct prison *pr, int flags)
3092 {
3093 	struct prisonlist freeprison;
3094 	struct prison *killpr, *rpr, *ppr, *tpr;
3095 
3096 	killpr = NULL;
3097 	TAILQ_INIT(&freeprison);
3098 	/*
3099 	 * Release this prison as requested, which may cause its parent
3100 	 * to be released, and then maybe its grandparent, etc.
3101 	 */
3102 	for (;;) {
3103 		if (flags & PD_KILL) {
3104 			/* Kill the prison and its descendents. */
3105 			KASSERT(pr != &prison0,
3106 			    ("prison_deref trying to kill prison0"));
3107 			if (!(flags & PD_DEREF)) {
3108 				prison_hold(pr);
3109 				flags |= PD_DEREF;
3110 			}
3111 			flags = prison_lock_xlock(pr, flags);
3112 			prison_deref_kill(pr, &freeprison);
3113 		}
3114 		if (flags & PD_DEUREF) {
3115 			/* Drop a user reference. */
3116 			KASSERT(refcount_load(&pr->pr_uref) > 0,
3117 			    ("prison_deref PD_DEUREF on a dead prison (jid=%d)",
3118 			     pr->pr_id));
3119 			if (!refcount_release_if_not_last(&pr->pr_uref)) {
3120 				if (!(flags & PD_DEREF)) {
3121 					prison_hold(pr);
3122 					flags |= PD_DEREF;
3123 				}
3124 				flags = prison_lock_xlock(pr, flags);
3125 				if (refcount_release(&pr->pr_uref) &&
3126 				    pr->pr_state == PRISON_STATE_ALIVE) {
3127 					/*
3128 					 * When the last user references goes,
3129 					 * this becomes a dying prison.
3130 					 */
3131 					KASSERT(
3132 					    refcount_load(&prison0.pr_uref) > 0,
3133 					    ("prison0 pr_uref=0"));
3134 					pr->pr_state = PRISON_STATE_DYING;
3135 					mtx_unlock(&pr->pr_mtx);
3136 					flags &= ~PD_LOCKED;
3137 					prison_cleanup(pr);
3138 				}
3139 			}
3140 		}
3141 		if (flags & PD_KILL) {
3142 			/*
3143 			 * Any remaining user references are probably processes
3144 			 * that need to be killed, either in this prison or its
3145 			 * descendants.
3146 			 */
3147 			if (refcount_load(&pr->pr_uref) > 0)
3148 				killpr = pr;
3149 			/* Make sure the parent prison doesn't get killed. */
3150 			flags &= ~PD_KILL;
3151 		}
3152 		if (flags & PD_DEREF) {
3153 			/* Drop a reference. */
3154 			KASSERT(refcount_load(&pr->pr_ref) > 0,
3155 			    ("prison_deref PD_DEREF on a dead prison (jid=%d)",
3156 			     pr->pr_id));
3157 			if (!refcount_release_if_not_last(&pr->pr_ref)) {
3158 				flags = prison_lock_xlock(pr, flags);
3159 				if (refcount_release(&pr->pr_ref)) {
3160 					/*
3161 					 * When the last reference goes,
3162 					 * unlink the prison and set it aside.
3163 					 */
3164 					KASSERT(
3165 					    refcount_load(&pr->pr_uref) == 0,
3166 					    ("prison_deref: last ref, "
3167 					     "but still has %d urefs (jid=%d)",
3168 					     pr->pr_uref, pr->pr_id));
3169 					KASSERT(
3170 					    refcount_load(&prison0.pr_ref) != 0,
3171 					    ("prison0 pr_ref=0"));
3172 					pr->pr_state = PRISON_STATE_INVALID;
3173 					TAILQ_REMOVE(&allprison, pr, pr_list);
3174 					LIST_REMOVE(pr, pr_sibling);
3175 					TAILQ_INSERT_TAIL(&freeprison, pr,
3176 					    pr_list);
3177 					for (ppr = pr->pr_parent;
3178 					     ppr != NULL;
3179 					     ppr = ppr->pr_parent)
3180 						ppr->pr_childcount--;
3181 					/*
3182 					 * Removing a prison frees references
3183 					 * from its parent.
3184 					 */
3185 					ppr = pr->pr_parent;
3186 					pr->pr_parent = NULL;
3187 					mtx_unlock(&pr->pr_mtx);
3188 
3189 					pr = ppr;
3190 					flags &= ~PD_LOCKED;
3191 					flags |= PD_DEREF | PD_DEUREF;
3192 					continue;
3193 				}
3194 			}
3195 		}
3196 		break;
3197 	}
3198 
3199 	/* Release all the prison locks. */
3200 	if (flags & PD_LOCKED)
3201 		mtx_unlock(&pr->pr_mtx);
3202 	if (flags & PD_LIST_SLOCKED)
3203 		sx_sunlock(&allprison_lock);
3204 	else if (flags & PD_LIST_XLOCKED)
3205 		sx_xunlock(&allprison_lock);
3206 
3207 	/* Kill any processes attached to a killed prison. */
3208 	if (killpr != NULL)
3209 		prison_proc_iterate(killpr, prison_kill_processes_cb, NULL);
3210 
3211 	/*
3212 	 * Finish removing any unreferenced prisons, which couldn't happen
3213 	 * while allprison_lock was held (to avoid a LOR on vrele).
3214 	 */
3215 	TAILQ_FOREACH_SAFE(rpr, &freeprison, pr_list, tpr) {
3216 #ifdef VIMAGE
3217 		if (rpr->pr_flags & PR_VNET)
3218 			vnet_destroy(rpr->pr_vnet);
3219 #endif
3220 		if (rpr->pr_root != NULL)
3221 			vrele(rpr->pr_root);
3222 		mtx_destroy(&rpr->pr_mtx);
3223 #ifdef INET
3224 		prison_ip_free(rpr->pr_addrs[PR_INET]);
3225 #endif
3226 #ifdef INET6
3227 		prison_ip_free(rpr->pr_addrs[PR_INET6]);
3228 #endif
3229 		if (rpr->pr_cpuset != NULL)
3230 			cpuset_rel(rpr->pr_cpuset);
3231 		osd_jail_exit(rpr);
3232 #ifdef RACCT
3233 		if (racct_enable)
3234 			prison_racct_detach(rpr);
3235 #endif
3236 		TAILQ_REMOVE(&freeprison, rpr, pr_list);
3237 		free(rpr, M_PRISON);
3238 	}
3239 }
3240 
3241 /*
3242  * Kill the prison and its descendants.  Mark them as dying, clear the
3243  * persist flag, and call module remove methods.
3244  */
3245 static void
prison_deref_kill(struct prison * pr,struct prisonlist * freeprison)3246 prison_deref_kill(struct prison *pr, struct prisonlist *freeprison)
3247 {
3248 	struct prison *cpr, *ppr, *rpr;
3249 	bool descend;
3250 
3251 	/*
3252 	 * Unlike the descendants, the target prison can be killed
3253 	 * even if it is currently dying.  This is useful for failed
3254 	 * creation in jail_set(2).
3255 	 */
3256 	KASSERT(refcount_load(&pr->pr_ref) > 0,
3257 	    ("Trying to kill dead prison %p (jid=%d).",
3258 	     pr, pr->pr_id));
3259 	refcount_acquire(&pr->pr_uref);
3260 	pr->pr_state = PRISON_STATE_DYING;
3261 	mtx_unlock(&pr->pr_mtx);
3262 
3263 	rpr = NULL;
3264 	FOREACH_PRISON_DESCENDANT_PRE_POST(pr, cpr, descend) {
3265 		if (descend) {
3266 			if (!prison_isalive(cpr)) {
3267 				descend = false;
3268 				continue;
3269 			}
3270 			prison_hold(cpr);
3271 			prison_proc_hold(cpr);
3272 			mtx_lock(&cpr->pr_mtx);
3273 			cpr->pr_state = PRISON_STATE_DYING;
3274 			cpr->pr_flags |= PR_REMOVE;
3275 			mtx_unlock(&cpr->pr_mtx);
3276 			continue;
3277 		}
3278 		if (!(cpr->pr_flags & PR_REMOVE))
3279 			continue;
3280 		prison_cleanup(cpr);
3281 		mtx_lock(&cpr->pr_mtx);
3282 		cpr->pr_flags &= ~PR_REMOVE;
3283 		if (cpr->pr_flags & PR_PERSIST) {
3284 			cpr->pr_flags &= ~PR_PERSIST;
3285 			prison_proc_free_not_last(cpr);
3286 			prison_free_not_last(cpr);
3287 		}
3288 		(void)refcount_release(&cpr->pr_uref);
3289 		if (refcount_release(&cpr->pr_ref)) {
3290 			/*
3291 			 * When the last reference goes, unlink the prison
3292 			 * and set it aside for prison_deref() to handle.
3293 			 * Delay unlinking the sibling list to keep the loop
3294 			 * safe.
3295 			 */
3296 			if (rpr != NULL)
3297 				LIST_REMOVE(rpr, pr_sibling);
3298 			rpr = cpr;
3299 			rpr->pr_state = PRISON_STATE_INVALID;
3300 			TAILQ_REMOVE(&allprison, rpr, pr_list);
3301 			TAILQ_INSERT_TAIL(freeprison, rpr, pr_list);
3302 			/*
3303 			 * Removing a prison frees references from its parent.
3304 			 */
3305 			ppr = rpr->pr_parent;
3306 			prison_proc_free_not_last(ppr);
3307 			prison_free_not_last(ppr);
3308 			for (; ppr != NULL; ppr = ppr->pr_parent)
3309 				ppr->pr_childcount--;
3310 		}
3311 		mtx_unlock(&cpr->pr_mtx);
3312 	}
3313 	if (rpr != NULL)
3314 		LIST_REMOVE(rpr, pr_sibling);
3315 
3316 	prison_cleanup(pr);
3317 	mtx_lock(&pr->pr_mtx);
3318 	if (pr->pr_flags & PR_PERSIST) {
3319 		pr->pr_flags &= ~PR_PERSIST;
3320 		prison_proc_free_not_last(pr);
3321 		prison_free_not_last(pr);
3322 	}
3323 	(void)refcount_release(&pr->pr_uref);
3324 }
3325 
3326 /*
3327  * Given the current locking state in the flags, make sure allprison_lock
3328  * is held exclusive, and the prison is locked.  Return flags indicating
3329  * the new state.
3330  */
3331 static int
prison_lock_xlock(struct prison * pr,int flags)3332 prison_lock_xlock(struct prison *pr, int flags)
3333 {
3334 
3335 	if (!(flags & PD_LIST_XLOCKED)) {
3336 		/*
3337 		 * Get allprison_lock, which may be an upgrade,
3338 		 * and may require unlocking the prison.
3339 		 */
3340 		if (flags & PD_LOCKED) {
3341 			mtx_unlock(&pr->pr_mtx);
3342 			flags &= ~PD_LOCKED;
3343 		}
3344 		if (flags & PD_LIST_SLOCKED) {
3345 			if (!sx_try_upgrade(&allprison_lock)) {
3346 				sx_sunlock(&allprison_lock);
3347 				sx_xlock(&allprison_lock);
3348 			}
3349 			flags &= ~PD_LIST_SLOCKED;
3350 		} else
3351 			sx_xlock(&allprison_lock);
3352 		flags |= PD_LIST_XLOCKED;
3353 	}
3354 	if (!(flags & PD_LOCKED)) {
3355 		/* Lock the prison mutex. */
3356 		mtx_lock(&pr->pr_mtx);
3357 		flags |= PD_LOCKED;
3358 	}
3359 	return flags;
3360 }
3361 
3362 /*
3363  * Release a prison's resources when it starts dying (when the last user
3364  * reference is dropped, or when it is killed).
3365  */
3366 static void
prison_cleanup(struct prison * pr)3367 prison_cleanup(struct prison *pr)
3368 {
3369 	sx_assert(&allprison_lock, SA_XLOCKED);
3370 	mtx_assert(&pr->pr_mtx, MA_NOTOWNED);
3371 	vfs_exjail_delete(pr);
3372 	shm_remove_prison(pr);
3373 	(void)osd_jail_call(pr, PR_METHOD_REMOVE, NULL);
3374 }
3375 
3376 /*
3377  * Set or clear a permission bit in the pr_allow field, passing restrictions
3378  * (cleared permission) down to child jails.
3379  */
3380 void
prison_set_allow(struct ucred * cred,unsigned flag,int enable)3381 prison_set_allow(struct ucred *cred, unsigned flag, int enable)
3382 {
3383 	struct prison *pr;
3384 
3385 	pr = cred->cr_prison;
3386 	sx_slock(&allprison_lock);
3387 	mtx_lock(&pr->pr_mtx);
3388 	prison_set_allow_locked(pr, flag, enable);
3389 	mtx_unlock(&pr->pr_mtx);
3390 	sx_sunlock(&allprison_lock);
3391 }
3392 
3393 static void
prison_set_allow_locked(struct prison * pr,unsigned flag,int enable)3394 prison_set_allow_locked(struct prison *pr, unsigned flag, int enable)
3395 {
3396 	struct prison *cpr;
3397 	int descend;
3398 
3399 	if (enable != 0)
3400 		pr->pr_allow |= flag;
3401 	else {
3402 		pr->pr_allow &= ~flag;
3403 		FOREACH_PRISON_DESCENDANT_LOCKED(pr, cpr, descend)
3404 			cpr->pr_allow &= ~flag;
3405 	}
3406 }
3407 
3408 /*
3409  * Check if a jail supports the given address family.
3410  *
3411  * Returns 0 if not jailed or the address family is supported, EAFNOSUPPORT
3412  * if not.
3413  */
3414 int
prison_check_af(struct ucred * cred,int af)3415 prison_check_af(struct ucred *cred, int af)
3416 {
3417 	struct prison *pr;
3418 	int error;
3419 
3420 	KASSERT(cred != NULL, ("%s: cred is NULL", __func__));
3421 
3422 	pr = cred->cr_prison;
3423 #ifdef VIMAGE
3424 	/* Prisons with their own network stack are not limited. */
3425 	if (prison_owns_vnet(cred))
3426 		return (0);
3427 #endif
3428 
3429 	error = 0;
3430 	switch (af)
3431 	{
3432 #ifdef INET
3433 	case AF_INET:
3434 		if (pr->pr_flags & PR_IP4)
3435 		{
3436 			mtx_lock(&pr->pr_mtx);
3437 			if ((pr->pr_flags & PR_IP4) &&
3438 			    pr->pr_addrs[PR_INET] == NULL)
3439 				error = EAFNOSUPPORT;
3440 			mtx_unlock(&pr->pr_mtx);
3441 		}
3442 		break;
3443 #endif
3444 #ifdef INET6
3445 	case AF_INET6:
3446 		if (pr->pr_flags & PR_IP6)
3447 		{
3448 			mtx_lock(&pr->pr_mtx);
3449 			if ((pr->pr_flags & PR_IP6) &&
3450 			    pr->pr_addrs[PR_INET6] == NULL)
3451 				error = EAFNOSUPPORT;
3452 			mtx_unlock(&pr->pr_mtx);
3453 		}
3454 		break;
3455 #endif
3456 	case AF_LOCAL:
3457 	case AF_ROUTE:
3458 	case AF_NETLINK:
3459 		break;
3460 	default:
3461 		if (!(pr->pr_allow & PR_ALLOW_SOCKET_AF))
3462 			error = EAFNOSUPPORT;
3463 	}
3464 	return (error);
3465 }
3466 
3467 /*
3468  * Check if given address belongs to the jail referenced by cred (wrapper to
3469  * prison_check_ip[46]).
3470  *
3471  * Returns 0 if jail doesn't restrict the address family or if address belongs
3472  * to jail, EADDRNOTAVAIL if the address doesn't belong, or EAFNOSUPPORT if
3473  * the jail doesn't allow the address family.  IPv4 Address passed in in NBO.
3474  */
3475 int
prison_if(struct ucred * cred,const struct sockaddr * sa)3476 prison_if(struct ucred *cred, const struct sockaddr *sa)
3477 {
3478 #ifdef INET
3479 	const struct sockaddr_in *sai;
3480 #endif
3481 #ifdef INET6
3482 	const struct sockaddr_in6 *sai6;
3483 #endif
3484 	int error;
3485 
3486 	KASSERT(cred != NULL, ("%s: cred is NULL", __func__));
3487 	KASSERT(sa != NULL, ("%s: sa is NULL", __func__));
3488 
3489 #ifdef VIMAGE
3490 	if (prison_owns_vnet(cred))
3491 		return (0);
3492 #endif
3493 
3494 	error = 0;
3495 	switch (sa->sa_family)
3496 	{
3497 #ifdef INET
3498 	case AF_INET:
3499 		sai = (const struct sockaddr_in *)sa;
3500 		error = prison_check_ip4(cred, &sai->sin_addr);
3501 		break;
3502 #endif
3503 #ifdef INET6
3504 	case AF_INET6:
3505 		sai6 = (const struct sockaddr_in6 *)sa;
3506 		error = prison_check_ip6(cred, &sai6->sin6_addr);
3507 		break;
3508 #endif
3509 	default:
3510 		if (!(cred->cr_prison->pr_allow & PR_ALLOW_SOCKET_AF))
3511 			error = EAFNOSUPPORT;
3512 	}
3513 	return (error);
3514 }
3515 
3516 /*
3517  * Return 0 if jails permit p1 to frob p2, otherwise ESRCH.
3518  */
3519 int
prison_check(struct ucred * cred1,struct ucred * cred2)3520 prison_check(struct ucred *cred1, struct ucred *cred2)
3521 {
3522 
3523 	return ((cred1->cr_prison == cred2->cr_prison ||
3524 	    prison_ischild(cred1->cr_prison, cred2->cr_prison)) ? 0 : ESRCH);
3525 }
3526 
3527 /*
3528  * For mountd/nfsd to run within a prison, it must be:
3529  * - A vnet prison.
3530  * - PR_ALLOW_NFSD must be set on it.
3531  * - The root directory (pr_root) of the prison must be
3532  *   a file system mount point, so the mountd can hang
3533  *   export information on it.
3534  * - The prison's enforce_statfs cannot be 0, so that
3535  *   mountd(8) can do exports.
3536  */
3537 bool
prison_check_nfsd(struct ucred * cred)3538 prison_check_nfsd(struct ucred *cred)
3539 {
3540 
3541 	if (jailed_without_vnet(cred))
3542 		return (false);
3543 	if (!prison_allow(cred, PR_ALLOW_NFSD))
3544 		return (false);
3545 	if ((cred->cr_prison->pr_root->v_vflag & VV_ROOT) == 0)
3546 		return (false);
3547 	if (cred->cr_prison->pr_enforce_statfs == 0)
3548 		return (false);
3549 	return (true);
3550 }
3551 
3552 /*
3553  * Return true if p2 is a child of p1, otherwise false.
3554  */
3555 bool
prison_ischild(struct prison * pr1,struct prison * pr2)3556 prison_ischild(struct prison *pr1, struct prison *pr2)
3557 {
3558 
3559 	for (pr2 = pr2->pr_parent; pr2 != NULL; pr2 = pr2->pr_parent)
3560 		if (pr1 == pr2)
3561 			return (true);
3562 	return (false);
3563 }
3564 
3565 /*
3566  * Return true if the prison is currently alive.  A prison is alive if it
3567  * holds user references and it isn't being removed.
3568  */
3569 bool
prison_isalive(const struct prison * pr)3570 prison_isalive(const struct prison *pr)
3571 {
3572 
3573 	if (__predict_false(pr->pr_state != PRISON_STATE_ALIVE))
3574 		return (false);
3575 	return (true);
3576 }
3577 
3578 /*
3579  * Return true if the prison is currently valid.  A prison is valid if it has
3580  * been fully created, and is not being destroyed.  Note that dying prisons
3581  * are still considered valid.  Invalid prisons won't be found under normal
3582  * circumstances, as they're only put in that state by functions that have
3583  * an exclusive hold on allprison_lock.
3584  */
3585 bool
prison_isvalid(struct prison * pr)3586 prison_isvalid(struct prison *pr)
3587 {
3588 
3589 	if (__predict_false(pr->pr_state == PRISON_STATE_INVALID))
3590 		return (false);
3591 	if (__predict_false(refcount_load(&pr->pr_ref) == 0))
3592 		return (false);
3593 	return (true);
3594 }
3595 
3596 /*
3597  * Return true if the passed credential is in a jail and that jail does not
3598  * have its own virtual network stack, otherwise false.
3599  */
3600 bool
jailed_without_vnet(struct ucred * cred)3601 jailed_without_vnet(struct ucred *cred)
3602 {
3603 
3604 	if (!jailed(cred))
3605 		return (false);
3606 #ifdef VIMAGE
3607 	if (prison_owns_vnet(cred))
3608 		return (false);
3609 #endif
3610 
3611 	return (true);
3612 }
3613 
3614 /*
3615  * Return the correct hostname (domainname, et al) for the passed credential.
3616  */
3617 void
getcredhostname(struct ucred * cred,char * buf,size_t size)3618 getcredhostname(struct ucred *cred, char *buf, size_t size)
3619 {
3620 	struct prison *pr;
3621 
3622 	/*
3623 	 * A NULL credential can be used to shortcut to the physical
3624 	 * system's hostname.
3625 	 */
3626 	pr = (cred != NULL) ? cred->cr_prison : &prison0;
3627 	mtx_lock(&pr->pr_mtx);
3628 	strlcpy(buf, pr->pr_hostname, size);
3629 	mtx_unlock(&pr->pr_mtx);
3630 }
3631 
3632 void
getcreddomainname(struct ucred * cred,char * buf,size_t size)3633 getcreddomainname(struct ucred *cred, char *buf, size_t size)
3634 {
3635 
3636 	mtx_lock(&cred->cr_prison->pr_mtx);
3637 	strlcpy(buf, cred->cr_prison->pr_domainname, size);
3638 	mtx_unlock(&cred->cr_prison->pr_mtx);
3639 }
3640 
3641 void
getcredhostuuid(struct ucred * cred,char * buf,size_t size)3642 getcredhostuuid(struct ucred *cred, char *buf, size_t size)
3643 {
3644 
3645 	mtx_lock(&cred->cr_prison->pr_mtx);
3646 	strlcpy(buf, cred->cr_prison->pr_hostuuid, size);
3647 	mtx_unlock(&cred->cr_prison->pr_mtx);
3648 }
3649 
3650 void
getcredhostid(struct ucred * cred,unsigned long * hostid)3651 getcredhostid(struct ucred *cred, unsigned long *hostid)
3652 {
3653 
3654 	mtx_lock(&cred->cr_prison->pr_mtx);
3655 	*hostid = cred->cr_prison->pr_hostid;
3656 	mtx_unlock(&cred->cr_prison->pr_mtx);
3657 }
3658 
3659 void
getjailname(struct ucred * cred,char * name,size_t len)3660 getjailname(struct ucred *cred, char *name, size_t len)
3661 {
3662 
3663 	mtx_lock(&cred->cr_prison->pr_mtx);
3664 	strlcpy(name, cred->cr_prison->pr_name, len);
3665 	mtx_unlock(&cred->cr_prison->pr_mtx);
3666 }
3667 
3668 #ifdef VIMAGE
3669 /*
3670  * Determine whether the prison represented by cred owns
3671  * its vnet rather than having it inherited.
3672  *
3673  * Returns true in case the prison owns the vnet, false otherwise.
3674  */
3675 bool
prison_owns_vnet(struct ucred * cred)3676 prison_owns_vnet(struct ucred *cred)
3677 {
3678 
3679 	/*
3680 	 * vnets cannot be added/removed after jail creation,
3681 	 * so no need to lock here.
3682 	 */
3683 	return ((cred->cr_prison->pr_flags & PR_VNET) != 0);
3684 }
3685 #endif
3686 
3687 /*
3688  * Determine whether the subject represented by cred can "see"
3689  * status of a mount point.
3690  * Returns: 0 for permitted, ENOENT otherwise.
3691  * XXX: This function should be called cr_canseemount() and should be
3692  *      placed in kern_prot.c.
3693  */
3694 int
prison_canseemount(struct ucred * cred,struct mount * mp)3695 prison_canseemount(struct ucred *cred, struct mount *mp)
3696 {
3697 	struct prison *pr;
3698 	struct statfs *sp;
3699 	size_t len;
3700 
3701 	pr = cred->cr_prison;
3702 	if (pr->pr_enforce_statfs == 0)
3703 		return (0);
3704 	if (pr->pr_root->v_mount == mp)
3705 		return (0);
3706 	if (pr->pr_enforce_statfs == 2)
3707 		return (ENOENT);
3708 	/*
3709 	 * If jail's chroot directory is set to "/" we should be able to see
3710 	 * all mount-points from inside a jail.
3711 	 * This is ugly check, but this is the only situation when jail's
3712 	 * directory ends with '/'.
3713 	 */
3714 	if (strcmp(pr->pr_path, "/") == 0)
3715 		return (0);
3716 	len = strlen(pr->pr_path);
3717 	sp = &mp->mnt_stat;
3718 	if (strncmp(pr->pr_path, sp->f_mntonname, len) != 0)
3719 		return (ENOENT);
3720 	/*
3721 	 * Be sure that we don't have situation where jail's root directory
3722 	 * is "/some/path" and mount point is "/some/pathpath".
3723 	 */
3724 	if (sp->f_mntonname[len] != '\0' && sp->f_mntonname[len] != '/')
3725 		return (ENOENT);
3726 	return (0);
3727 }
3728 
3729 void
prison_enforce_statfs(struct ucred * cred,struct mount * mp,struct statfs * sp)3730 prison_enforce_statfs(struct ucred *cred, struct mount *mp, struct statfs *sp)
3731 {
3732 	char jpath[MAXPATHLEN];
3733 	struct prison *pr;
3734 	size_t len;
3735 
3736 	pr = cred->cr_prison;
3737 	if (pr->pr_enforce_statfs == 0)
3738 		return;
3739 	if (prison_canseemount(cred, mp) != 0) {
3740 		bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
3741 		strlcpy(sp->f_mntonname, "[restricted]",
3742 		    sizeof(sp->f_mntonname));
3743 		return;
3744 	}
3745 	if (pr->pr_root->v_mount == mp) {
3746 		/*
3747 		 * Clear current buffer data, so we are sure nothing from
3748 		 * the valid path left there.
3749 		 */
3750 		bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
3751 		*sp->f_mntonname = '/';
3752 		return;
3753 	}
3754 	/*
3755 	 * If jail's chroot directory is set to "/" we should be able to see
3756 	 * all mount-points from inside a jail.
3757 	 */
3758 	if (strcmp(pr->pr_path, "/") == 0)
3759 		return;
3760 	len = strlen(pr->pr_path);
3761 	strlcpy(jpath, sp->f_mntonname + len, sizeof(jpath));
3762 	/*
3763 	 * Clear current buffer data, so we are sure nothing from
3764 	 * the valid path left there.
3765 	 */
3766 	bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
3767 	if (*jpath == '\0') {
3768 		/* Should never happen. */
3769 		*sp->f_mntonname = '/';
3770 	} else {
3771 		strlcpy(sp->f_mntonname, jpath, sizeof(sp->f_mntonname));
3772 	}
3773 }
3774 
3775 /*
3776  * Check with permission for a specific privilege is granted within jail.  We
3777  * have a specific list of accepted privileges; the rest are denied.
3778  */
3779 int
prison_priv_check(struct ucred * cred,int priv)3780 prison_priv_check(struct ucred *cred, int priv)
3781 {
3782 	struct prison *pr;
3783 	int error;
3784 
3785 	/*
3786 	 * Some policies have custom handlers. This routine should not be
3787 	 * called for them. See priv_check_cred().
3788 	 */
3789 	switch (priv) {
3790 	case PRIV_VFS_LOOKUP:
3791 	case PRIV_VFS_GENERATION:
3792 		KASSERT(0, ("prison_priv_check instead of a custom handler "
3793 		    "called for %d\n", priv));
3794 	}
3795 
3796 	if (!jailed(cred))
3797 		return (0);
3798 
3799 #ifdef VIMAGE
3800 	/*
3801 	 * Privileges specific to prisons with a virtual network stack.
3802 	 * There might be a duplicate entry here in case the privilege
3803 	 * is only granted conditionally in the legacy jail case.
3804 	 */
3805 	switch (priv) {
3806 		/*
3807 		 * NFS-specific privileges.
3808 		 */
3809 	case PRIV_NFS_DAEMON:
3810 	case PRIV_VFS_GETFH:
3811 	case PRIV_VFS_MOUNT_EXPORTED:
3812 		if (!prison_check_nfsd(cred))
3813 			return (EPERM);
3814 #ifdef notyet
3815 	case PRIV_NFS_LOCKD:
3816 #endif
3817 		/*
3818 		 * Network stack privileges.
3819 		 */
3820 	case PRIV_NET_BRIDGE:
3821 	case PRIV_NET_GRE:
3822 	case PRIV_NET_BPF:
3823 	case PRIV_NET_RAW:		/* Dup, cond. in legacy jail case. */
3824 	case PRIV_NET_ROUTE:
3825 	case PRIV_NET_TAP:
3826 	case PRIV_NET_SETIFMTU:
3827 	case PRIV_NET_SETIFFLAGS:
3828 	case PRIV_NET_SETIFCAP:
3829 	case PRIV_NET_SETIFDESCR:
3830 	case PRIV_NET_SETIFNAME	:
3831 	case PRIV_NET_SETIFMETRIC:
3832 	case PRIV_NET_SETIFPHYS:
3833 	case PRIV_NET_SETIFMAC:
3834 	case PRIV_NET_SETLANPCP:
3835 	case PRIV_NET_ADDMULTI:
3836 	case PRIV_NET_DELMULTI:
3837 	case PRIV_NET_HWIOCTL:
3838 	case PRIV_NET_SETLLADDR:
3839 	case PRIV_NET_ADDIFGROUP:
3840 	case PRIV_NET_DELIFGROUP:
3841 	case PRIV_NET_IFCREATE:
3842 	case PRIV_NET_IFDESTROY:
3843 	case PRIV_NET_ADDIFADDR:
3844 	case PRIV_NET_DELIFADDR:
3845 	case PRIV_NET_LAGG:
3846 	case PRIV_NET_GIF:
3847 	case PRIV_NET_SETIFVNET:
3848 	case PRIV_NET_SETIFFIB:
3849 	case PRIV_NET_OVPN:
3850 	case PRIV_NET_ME:
3851 	case PRIV_NET_WG:
3852 
3853 		/*
3854 		 * 802.11-related privileges.
3855 		 */
3856 	case PRIV_NET80211_VAP_GETKEY:
3857 	case PRIV_NET80211_VAP_MANAGE:
3858 
3859 #ifdef notyet
3860 		/*
3861 		 * ATM privileges.
3862 		 */
3863 	case PRIV_NETATM_CFG:
3864 	case PRIV_NETATM_ADD:
3865 	case PRIV_NETATM_DEL:
3866 	case PRIV_NETATM_SET:
3867 
3868 		/*
3869 		 * Bluetooth privileges.
3870 		 */
3871 	case PRIV_NETBLUETOOTH_RAW:
3872 #endif
3873 
3874 		/*
3875 		 * Netgraph and netgraph module privileges.
3876 		 */
3877 	case PRIV_NETGRAPH_CONTROL:
3878 #ifdef notyet
3879 	case PRIV_NETGRAPH_TTY:
3880 #endif
3881 
3882 		/*
3883 		 * IPv4 and IPv6 privileges.
3884 		 */
3885 	case PRIV_NETINET_IPFW:
3886 	case PRIV_NETINET_DIVERT:
3887 	case PRIV_NETINET_PF:
3888 	case PRIV_NETINET_DUMMYNET:
3889 	case PRIV_NETINET_CARP:
3890 	case PRIV_NETINET_MROUTE:
3891 	case PRIV_NETINET_RAW:
3892 	case PRIV_NETINET_ADDRCTRL6:
3893 	case PRIV_NETINET_ND6:
3894 	case PRIV_NETINET_SCOPE6:
3895 	case PRIV_NETINET_ALIFETIME6:
3896 	case PRIV_NETINET_IPSEC:
3897 	case PRIV_NETINET_BINDANY:
3898 
3899 #ifdef notyet
3900 		/*
3901 		 * NCP privileges.
3902 		 */
3903 	case PRIV_NETNCP:
3904 
3905 		/*
3906 		 * SMB privileges.
3907 		 */
3908 	case PRIV_NETSMB:
3909 #endif
3910 
3911 	/*
3912 	 * No default: or deny here.
3913 	 * In case of no permit fall through to next switch().
3914 	 */
3915 		if (cred->cr_prison->pr_flags & PR_VNET)
3916 			return (0);
3917 	}
3918 #endif /* VIMAGE */
3919 
3920 	switch (priv) {
3921 		/*
3922 		 * Allow ktrace privileges for root in jail.
3923 		 */
3924 	case PRIV_KTRACE:
3925 
3926 #if 0
3927 		/*
3928 		 * Allow jailed processes to configure audit identity and
3929 		 * submit audit records (login, etc).  In the future we may
3930 		 * want to further refine the relationship between audit and
3931 		 * jail.
3932 		 */
3933 	case PRIV_AUDIT_GETAUDIT:
3934 	case PRIV_AUDIT_SETAUDIT:
3935 	case PRIV_AUDIT_SUBMIT:
3936 #endif
3937 
3938 		/*
3939 		 * Allow jailed processes to manipulate process UNIX
3940 		 * credentials in any way they see fit.
3941 		 */
3942 	case PRIV_CRED_SETCRED:
3943 	case PRIV_CRED_SETUID:
3944 	case PRIV_CRED_SETEUID:
3945 	case PRIV_CRED_SETGID:
3946 	case PRIV_CRED_SETEGID:
3947 	case PRIV_CRED_SETGROUPS:
3948 	case PRIV_CRED_SETREUID:
3949 	case PRIV_CRED_SETREGID:
3950 	case PRIV_CRED_SETRESUID:
3951 	case PRIV_CRED_SETRESGID:
3952 
3953 		/*
3954 		 * Jail implements visibility constraints already, so allow
3955 		 * jailed root to override uid/gid-based constraints.
3956 		 */
3957 	case PRIV_SEEOTHERGIDS:
3958 	case PRIV_SEEOTHERUIDS:
3959 	case PRIV_SEEJAILPROC:
3960 
3961 		/*
3962 		 * Jail implements inter-process debugging limits already, so
3963 		 * allow jailed root various debugging privileges.
3964 		 */
3965 	case PRIV_DEBUG_DIFFCRED:
3966 	case PRIV_DEBUG_SUGID:
3967 	case PRIV_DEBUG_UNPRIV:
3968 
3969 		/*
3970 		 * Allow jail to set various resource limits and login
3971 		 * properties, and for now, exceed process resource limits.
3972 		 */
3973 	case PRIV_PROC_LIMIT:
3974 	case PRIV_PROC_SETLOGIN:
3975 	case PRIV_PROC_SETRLIMIT:
3976 
3977 		/*
3978 		 * System V and POSIX IPC privileges are granted in jail.
3979 		 */
3980 	case PRIV_IPC_READ:
3981 	case PRIV_IPC_WRITE:
3982 	case PRIV_IPC_ADMIN:
3983 	case PRIV_IPC_MSGSIZE:
3984 	case PRIV_MQ_ADMIN:
3985 
3986 		/*
3987 		 * Jail operations within a jail work on child jails.
3988 		 */
3989 	case PRIV_JAIL_ATTACH:
3990 	case PRIV_JAIL_SET:
3991 	case PRIV_JAIL_REMOVE:
3992 
3993 		/*
3994 		 * Jail implements its own inter-process limits, so allow
3995 		 * root processes in jail to change scheduling on other
3996 		 * processes in the same jail.  Likewise for signalling.
3997 		 */
3998 	case PRIV_SCHED_DIFFCRED:
3999 	case PRIV_SCHED_CPUSET:
4000 	case PRIV_SIGNAL_DIFFCRED:
4001 	case PRIV_SIGNAL_SUGID:
4002 
4003 		/*
4004 		 * Allow jailed processes to write to sysctls marked as jail
4005 		 * writable.
4006 		 */
4007 	case PRIV_SYSCTL_WRITEJAIL:
4008 
4009 		/*
4010 		 * Allow root in jail to manage a variety of quota
4011 		 * properties.  These should likely be conditional on a
4012 		 * configuration option.
4013 		 */
4014 	case PRIV_VFS_GETQUOTA:
4015 	case PRIV_VFS_SETQUOTA:
4016 
4017 		/*
4018 		 * Since Jail relies on chroot() to implement file system
4019 		 * protections, grant many VFS privileges to root in jail.
4020 		 * Be careful to exclude mount-related and NFS-related
4021 		 * privileges.
4022 		 */
4023 	case PRIV_VFS_READ:
4024 	case PRIV_VFS_WRITE:
4025 	case PRIV_VFS_ADMIN:
4026 	case PRIV_VFS_EXEC:
4027 	case PRIV_VFS_BLOCKRESERVE:	/* XXXRW: Slightly surprising. */
4028 	case PRIV_VFS_CHFLAGS_DEV:
4029 	case PRIV_VFS_CHOWN:
4030 	case PRIV_VFS_CHROOT:
4031 	case PRIV_VFS_RETAINSUGID:
4032 	case PRIV_VFS_FCHROOT:
4033 	case PRIV_VFS_LINK:
4034 	case PRIV_VFS_SETGID:
4035 	case PRIV_VFS_STAT:
4036 	case PRIV_VFS_STICKYFILE:
4037 
4038 		/*
4039 		 * As in the non-jail case, non-root users are expected to be
4040 		 * able to read kernel/physical memory (provided /dev/[k]mem
4041 		 * exists in the jail and they have permission to access it).
4042 		 */
4043 	case PRIV_KMEM_READ:
4044 		return (0);
4045 
4046 		/*
4047 		 * Depending on the global setting, allow privilege of
4048 		 * setting system flags.
4049 		 */
4050 	case PRIV_VFS_SYSFLAGS:
4051 		if (cred->cr_prison->pr_allow & PR_ALLOW_CHFLAGS)
4052 			return (0);
4053 		else
4054 			return (EPERM);
4055 
4056 		/*
4057 		 * Depending on the global setting, allow privilege of
4058 		 * mounting/unmounting file systems.
4059 		 */
4060 	case PRIV_VFS_MOUNT:
4061 	case PRIV_VFS_UNMOUNT:
4062 	case PRIV_VFS_MOUNT_NONUSER:
4063 	case PRIV_VFS_MOUNT_OWNER:
4064 		pr = cred->cr_prison;
4065 		prison_lock(pr);
4066 		if (pr->pr_allow & PR_ALLOW_MOUNT && pr->pr_enforce_statfs < 2)
4067 			error = 0;
4068 		else
4069 			error = EPERM;
4070 		prison_unlock(pr);
4071 		return (error);
4072 
4073 		/*
4074 		 * Jails should hold no disposition on the PRIV_VFS_READ_DIR
4075 		 * policy.  priv_check_cred will not specifically allow it, and
4076 		 * we may want a MAC policy to allow it.
4077 		 */
4078 	case PRIV_VFS_READ_DIR:
4079 		return (0);
4080 
4081 		/*
4082 		 * Conditionnaly allow locking (unlocking) physical pages
4083 		 * in memory.
4084 		 */
4085 	case PRIV_VM_MLOCK:
4086 	case PRIV_VM_MUNLOCK:
4087 		if (cred->cr_prison->pr_allow & PR_ALLOW_MLOCK)
4088 			return (0);
4089 		else
4090 			return (EPERM);
4091 
4092 		/*
4093 		 * Conditionally allow jailed root to bind reserved ports.
4094 		 */
4095 	case PRIV_NETINET_RESERVEDPORT:
4096 		if (cred->cr_prison->pr_allow & PR_ALLOW_RESERVED_PORTS)
4097 			return (0);
4098 		else
4099 			return (EPERM);
4100 
4101 		/*
4102 		 * Allow jailed root to reuse in-use ports.
4103 		 */
4104 	case PRIV_NETINET_REUSEPORT:
4105 		return (0);
4106 
4107 		/*
4108 		 * Allow jailed root to set certain IPv4/6 (option) headers.
4109 		 */
4110 	case PRIV_NETINET_SETHDROPTS:
4111 		return (0);
4112 
4113 		/*
4114 		 * Conditionally allow creating raw sockets in jail.
4115 		 */
4116 	case PRIV_NETINET_RAW:
4117 		if (cred->cr_prison->pr_allow & PR_ALLOW_RAW_SOCKETS)
4118 			return (0);
4119 		else
4120 			return (EPERM);
4121 
4122 		/*
4123 		 * Since jail implements its own visibility limits on netstat
4124 		 * sysctls, allow getcred.  This allows identd to work in
4125 		 * jail.
4126 		 */
4127 	case PRIV_NETINET_GETCRED:
4128 		return (0);
4129 
4130 		/*
4131 		 * Allow jailed root to set loginclass.
4132 		 */
4133 	case PRIV_PROC_SETLOGINCLASS:
4134 		return (0);
4135 
4136 		/*
4137 		 * Do not allow a process inside a jail to read the kernel
4138 		 * message buffer unless explicitly permitted.
4139 		 */
4140 	case PRIV_MSGBUF:
4141 		if (cred->cr_prison->pr_allow & PR_ALLOW_READ_MSGBUF)
4142 			return (0);
4143 		return (EPERM);
4144 
4145 	default:
4146 		/*
4147 		 * In all remaining cases, deny the privilege request.  This
4148 		 * includes almost all network privileges, many system
4149 		 * configuration privileges.
4150 		 */
4151 		return (EPERM);
4152 	}
4153 }
4154 
4155 /*
4156  * Return the part of pr2's name that is relative to pr1, or the whole name
4157  * if it does not directly follow.
4158  */
4159 
4160 char *
prison_name(struct prison * pr1,struct prison * pr2)4161 prison_name(struct prison *pr1, struct prison *pr2)
4162 {
4163 	char *name;
4164 
4165 	/* Jails see themselves as "0" (if they see themselves at all). */
4166 	if (pr1 == pr2)
4167 		return "0";
4168 	name = pr2->pr_name;
4169 	if (prison_ischild(pr1, pr2)) {
4170 		/*
4171 		 * pr1 isn't locked (and allprison_lock may not be either)
4172 		 * so its length can't be counted on.  But the number of dots
4173 		 * can be counted on - and counted.
4174 		 */
4175 		for (; pr1 != &prison0; pr1 = pr1->pr_parent)
4176 			name = strchr(name, '.') + 1;
4177 	}
4178 	return (name);
4179 }
4180 
4181 /*
4182  * Return the part of pr2's path that is relative to pr1, or the whole path
4183  * if it does not directly follow.
4184  */
4185 static char *
prison_path(struct prison * pr1,struct prison * pr2)4186 prison_path(struct prison *pr1, struct prison *pr2)
4187 {
4188 	char *path1, *path2;
4189 	int len1;
4190 
4191 	path1 = pr1->pr_path;
4192 	path2 = pr2->pr_path;
4193 	if (!strcmp(path1, "/"))
4194 		return (path2);
4195 	len1 = strlen(path1);
4196 	if (strncmp(path1, path2, len1))
4197 		return (path2);
4198 	if (path2[len1] == '\0')
4199 		return "/";
4200 	if (path2[len1] == '/')
4201 		return (path2 + len1);
4202 	return (path2);
4203 }
4204 
4205 /*
4206  * Jail-related sysctls.
4207  */
4208 static SYSCTL_NODE(_security, OID_AUTO, jail, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
4209     "Jails");
4210 
4211 #if defined(INET) || defined(INET6)
4212 /*
4213  * Copy address array to memory that would be then SYSCTL_OUT-ed.
4214  * sysctl_jail_list() helper.
4215  */
4216 static void
prison_ip_copyout(struct prison * pr,const pr_family_t af,void ** out,int * len)4217 prison_ip_copyout(struct prison *pr, const pr_family_t af, void **out, int *len)
4218 {
4219 	const struct prison_ip *pip;
4220 	const size_t size = pr_families[af].size;
4221 
4222  again:
4223 	mtx_assert(&pr->pr_mtx, MA_OWNED);
4224 	if ((pip = pr->pr_addrs[af]) != NULL) {
4225 		if (*len < pip->ips) {
4226 			*len = pip->ips;
4227 			mtx_unlock(&pr->pr_mtx);
4228 			*out = realloc(*out, *len * size, M_TEMP, M_WAITOK);
4229 			mtx_lock(&pr->pr_mtx);
4230 			goto again;
4231 		}
4232 		bcopy(pip->pr_ip, *out, pip->ips * size);
4233 	}
4234 }
4235 #endif
4236 
4237 static int
sysctl_jail_list(SYSCTL_HANDLER_ARGS)4238 sysctl_jail_list(SYSCTL_HANDLER_ARGS)
4239 {
4240 	struct xprison *xp;
4241 	struct prison *pr, *cpr;
4242 #ifdef INET
4243 	struct in_addr *ip4 = NULL;
4244 	int ip4s = 0;
4245 #endif
4246 #ifdef INET6
4247 	struct in6_addr *ip6 = NULL;
4248 	int ip6s = 0;
4249 #endif
4250 	int descend, error;
4251 
4252 	xp = malloc(sizeof(*xp), M_TEMP, M_WAITOK);
4253 	pr = req->td->td_ucred->cr_prison;
4254 	error = 0;
4255 	sx_slock(&allprison_lock);
4256 	FOREACH_PRISON_DESCENDANT(pr, cpr, descend) {
4257 		mtx_lock(&cpr->pr_mtx);
4258 #ifdef INET
4259 		prison_ip_copyout(cpr, PR_INET, (void **)&ip4, &ip4s);
4260 #endif
4261 #ifdef INET6
4262 		prison_ip_copyout(cpr, PR_INET6, (void **)&ip6, &ip6s);
4263 #endif
4264 		bzero(xp, sizeof(*xp));
4265 		xp->pr_version = XPRISON_VERSION;
4266 		xp->pr_id = cpr->pr_id;
4267 		xp->pr_state = cpr->pr_state;
4268 		strlcpy(xp->pr_path, prison_path(pr, cpr), sizeof(xp->pr_path));
4269 		strlcpy(xp->pr_host, cpr->pr_hostname, sizeof(xp->pr_host));
4270 		strlcpy(xp->pr_name, prison_name(pr, cpr), sizeof(xp->pr_name));
4271 #ifdef INET
4272 		xp->pr_ip4s = ip4s;
4273 #endif
4274 #ifdef INET6
4275 		xp->pr_ip6s = ip6s;
4276 #endif
4277 		mtx_unlock(&cpr->pr_mtx);
4278 		error = SYSCTL_OUT(req, xp, sizeof(*xp));
4279 		if (error)
4280 			break;
4281 #ifdef INET
4282 		if (xp->pr_ip4s > 0) {
4283 			error = SYSCTL_OUT(req, ip4,
4284 			    xp->pr_ip4s * sizeof(struct in_addr));
4285 			if (error)
4286 				break;
4287 		}
4288 #endif
4289 #ifdef INET6
4290 		if (xp->pr_ip6s > 0) {
4291 			error = SYSCTL_OUT(req, ip6,
4292 			    xp->pr_ip6s * sizeof(struct in6_addr));
4293 			if (error)
4294 				break;
4295 		}
4296 #endif
4297 	}
4298 	sx_sunlock(&allprison_lock);
4299 	free(xp, M_TEMP);
4300 #ifdef INET
4301 	free(ip4, M_TEMP);
4302 #endif
4303 #ifdef INET6
4304 	free(ip6, M_TEMP);
4305 #endif
4306 	return (error);
4307 }
4308 
4309 SYSCTL_OID(_security_jail, OID_AUTO, list,
4310     CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
4311     sysctl_jail_list, "S", "List of active jails");
4312 
4313 static int
sysctl_jail_jailed(SYSCTL_HANDLER_ARGS)4314 sysctl_jail_jailed(SYSCTL_HANDLER_ARGS)
4315 {
4316 	int error, injail;
4317 
4318 	injail = jailed(req->td->td_ucred);
4319 	error = SYSCTL_OUT(req, &injail, sizeof(injail));
4320 
4321 	return (error);
4322 }
4323 
4324 SYSCTL_PROC(_security_jail, OID_AUTO, jailed,
4325     CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
4326     sysctl_jail_jailed, "I", "Process in jail?");
4327 
4328 static int
sysctl_jail_vnet(SYSCTL_HANDLER_ARGS)4329 sysctl_jail_vnet(SYSCTL_HANDLER_ARGS)
4330 {
4331 	int error, havevnet;
4332 #ifdef VIMAGE
4333 	struct ucred *cred = req->td->td_ucred;
4334 
4335 	havevnet = jailed(cred) && prison_owns_vnet(cred);
4336 #else
4337 	havevnet = 0;
4338 #endif
4339 	error = SYSCTL_OUT(req, &havevnet, sizeof(havevnet));
4340 
4341 	return (error);
4342 }
4343 
4344 SYSCTL_PROC(_security_jail, OID_AUTO, vnet,
4345     CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
4346     sysctl_jail_vnet, "I", "Jail owns vnet?");
4347 
4348 #if defined(INET) || defined(INET6)
4349 SYSCTL_UINT(_security_jail, OID_AUTO, jail_max_af_ips, CTLFLAG_RW,
4350     &jail_max_af_ips, 0,
4351     "Number of IP addresses a jail may have at most per address family (deprecated)");
4352 #endif
4353 
4354 /*
4355  * Default parameters for jail(2) compatibility.  For historical reasons,
4356  * the sysctl names have varying similarity to the parameter names.  Prisons
4357  * just see their own parameters, and can't change them.
4358  */
4359 static int
sysctl_jail_default_allow(SYSCTL_HANDLER_ARGS)4360 sysctl_jail_default_allow(SYSCTL_HANDLER_ARGS)
4361 {
4362 	int error, i;
4363 
4364 	/* Get the current flag value, and convert it to a boolean. */
4365 	if (req->td->td_ucred->cr_prison == &prison0) {
4366 		mtx_lock(&prison0.pr_mtx);
4367 		i = (jail_default_allow & arg2) != 0;
4368 		mtx_unlock(&prison0.pr_mtx);
4369 	} else
4370 		i = prison_allow(req->td->td_ucred, arg2);
4371 
4372 	if (arg1 != NULL)
4373 		i = !i;
4374 	error = sysctl_handle_int(oidp, &i, 0, req);
4375 	if (error || !req->newptr)
4376 		return (error);
4377 	i = i ? arg2 : 0;
4378 	if (arg1 != NULL)
4379 		i ^= arg2;
4380 	/*
4381 	 * The sysctls don't have CTLFLAGS_PRISON, so assume prison0
4382 	 * for writing.
4383 	 */
4384 	mtx_lock(&prison0.pr_mtx);
4385 	jail_default_allow = (jail_default_allow & ~arg2) | i;
4386 	mtx_unlock(&prison0.pr_mtx);
4387 	return (0);
4388 }
4389 
4390 SYSCTL_PROC(_security_jail, OID_AUTO, set_hostname_allowed,
4391     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4392     NULL, PR_ALLOW_SET_HOSTNAME, sysctl_jail_default_allow, "I",
4393     "Processes in jail can set their hostnames (deprecated)");
4394 SYSCTL_PROC(_security_jail, OID_AUTO, socket_unixiproute_only,
4395     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4396     (void *)1, PR_ALLOW_SOCKET_AF, sysctl_jail_default_allow, "I",
4397     "Processes in jail are limited to creating UNIX/IP/route sockets only (deprecated)");
4398 SYSCTL_PROC(_security_jail, OID_AUTO, sysvipc_allowed,
4399     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4400     NULL, PR_ALLOW_SYSVIPC, sysctl_jail_default_allow, "I",
4401     "Processes in jail can use System V IPC primitives (deprecated)");
4402 SYSCTL_PROC(_security_jail, OID_AUTO, allow_raw_sockets,
4403     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4404     NULL, PR_ALLOW_RAW_SOCKETS, sysctl_jail_default_allow, "I",
4405     "Prison root can create raw sockets (deprecated)");
4406 SYSCTL_PROC(_security_jail, OID_AUTO, chflags_allowed,
4407     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4408     NULL, PR_ALLOW_CHFLAGS, sysctl_jail_default_allow, "I",
4409     "Processes in jail can alter system file flags (deprecated)");
4410 SYSCTL_PROC(_security_jail, OID_AUTO, mount_allowed,
4411     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4412     NULL, PR_ALLOW_MOUNT, sysctl_jail_default_allow, "I",
4413     "Processes in jail can mount/unmount jail-friendly file systems (deprecated)");
4414 SYSCTL_PROC(_security_jail, OID_AUTO, mlock_allowed,
4415     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4416     NULL, PR_ALLOW_MLOCK, sysctl_jail_default_allow, "I",
4417     "Processes in jail can lock/unlock physical pages in memory");
4418 
4419 static int
sysctl_jail_default_level(SYSCTL_HANDLER_ARGS)4420 sysctl_jail_default_level(SYSCTL_HANDLER_ARGS)
4421 {
4422 	struct prison *pr;
4423 	int level, error;
4424 
4425 	pr = req->td->td_ucred->cr_prison;
4426 	level = (pr == &prison0) ? *(int *)arg1 : *(int *)((char *)pr + arg2);
4427 	error = sysctl_handle_int(oidp, &level, 0, req);
4428 	if (error || !req->newptr)
4429 		return (error);
4430 	*(int *)arg1 = level;
4431 	return (0);
4432 }
4433 
4434 SYSCTL_PROC(_security_jail, OID_AUTO, enforce_statfs,
4435     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4436     &jail_default_enforce_statfs, offsetof(struct prison, pr_enforce_statfs),
4437     sysctl_jail_default_level, "I",
4438     "Processes in jail cannot see all mounted file systems (deprecated)");
4439 
4440 SYSCTL_PROC(_security_jail, OID_AUTO, devfs_ruleset,
4441     CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
4442     &jail_default_devfs_rsnum, offsetof(struct prison, pr_devfs_rsnum),
4443     sysctl_jail_default_level, "I",
4444     "Ruleset for the devfs filesystem in jail (deprecated)");
4445 
4446 SYSCTL_NODE(_security_jail, OID_AUTO, children, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
4447     "Limits and stats of child jails");
4448 
4449 static int
sysctl_jail_children(SYSCTL_HANDLER_ARGS)4450 sysctl_jail_children(SYSCTL_HANDLER_ARGS)
4451 {
4452 	struct prison *pr;
4453 	int i;
4454 
4455 	pr = req->td->td_ucred->cr_prison;
4456 
4457 	switch (oidp->oid_kind & CTLTYPE) {
4458 	case CTLTYPE_INT:
4459 		i = *(int *)((char *)pr + arg2);
4460 		return (SYSCTL_OUT(req, &i, sizeof(i)));
4461 	}
4462 
4463 	return (0);
4464 }
4465 
4466 SYSCTL_PROC(_security_jail_children, OID_AUTO, max,
4467     CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
4468     NULL, offsetof(struct prison, pr_childmax), sysctl_jail_children,
4469     "I", "Maximum number of child jails");
4470 SYSCTL_PROC(_security_jail_children, OID_AUTO, cur,
4471     CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
4472     NULL, offsetof(struct prison, pr_childcount), sysctl_jail_children,
4473     "I", "Current number of child jails");
4474 
4475 /*
4476  * Nodes to describe jail parameters.  Maximum length of string parameters
4477  * is returned in the string itself, and the other parameters exist merely
4478  * to make themselves and their types known.
4479  */
4480 SYSCTL_NODE(_security_jail, OID_AUTO, param, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
4481     "Jail parameters");
4482 
4483 int
sysctl_jail_param(SYSCTL_HANDLER_ARGS)4484 sysctl_jail_param(SYSCTL_HANDLER_ARGS)
4485 {
4486 	int i;
4487 	long l;
4488 	size_t s;
4489 	char numbuf[12];
4490 
4491 	switch (oidp->oid_kind & CTLTYPE)
4492 	{
4493 	case CTLTYPE_LONG:
4494 	case CTLTYPE_ULONG:
4495 		l = 0;
4496 #ifdef SCTL_MASK32
4497 		if (!(req->flags & SCTL_MASK32))
4498 #endif
4499 			return (SYSCTL_OUT(req, &l, sizeof(l)));
4500 	case CTLTYPE_INT:
4501 	case CTLTYPE_UINT:
4502 		i = 0;
4503 		return (SYSCTL_OUT(req, &i, sizeof(i)));
4504 	case CTLTYPE_STRING:
4505 		snprintf(numbuf, sizeof(numbuf), "%jd", (intmax_t)arg2);
4506 		return
4507 		    (sysctl_handle_string(oidp, numbuf, sizeof(numbuf), req));
4508 	case CTLTYPE_STRUCT:
4509 		s = (size_t)arg2;
4510 		return (SYSCTL_OUT(req, &s, sizeof(s)));
4511 	}
4512 	return (0);
4513 }
4514 
4515 /*
4516  * CTLFLAG_RDTUN in the following indicates jail parameters that can be set at
4517  * jail creation time but cannot be changed in an existing jail.
4518  */
4519 SYSCTL_JAIL_PARAM(, jid, CTLTYPE_INT | CTLFLAG_RDTUN, "I", "Jail ID");
4520 SYSCTL_JAIL_PARAM(, parent, CTLTYPE_INT | CTLFLAG_RD, "I", "Jail parent ID");
4521 SYSCTL_JAIL_PARAM_STRING(, name, CTLFLAG_RW, MAXHOSTNAMELEN, "Jail name");
4522 SYSCTL_JAIL_PARAM_STRING(, path, CTLFLAG_RDTUN, MAXPATHLEN, "Jail root path");
4523 SYSCTL_JAIL_PARAM(, securelevel, CTLTYPE_INT | CTLFLAG_RW,
4524     "I", "Jail secure level");
4525 SYSCTL_JAIL_PARAM(, osreldate, CTLTYPE_INT | CTLFLAG_RDTUN, "I",
4526     "Jail value for kern.osreldate and uname -K");
4527 SYSCTL_JAIL_PARAM_STRING(, osrelease, CTLFLAG_RDTUN, OSRELEASELEN,
4528     "Jail value for kern.osrelease and uname -r");
4529 SYSCTL_JAIL_PARAM(, enforce_statfs, CTLTYPE_INT | CTLFLAG_RW,
4530     "I", "Jail cannot see all mounted file systems");
4531 SYSCTL_JAIL_PARAM(, devfs_ruleset, CTLTYPE_INT | CTLFLAG_RW,
4532     "I", "Ruleset for in-jail devfs mounts");
4533 SYSCTL_JAIL_PARAM(, persist, CTLTYPE_INT | CTLFLAG_RW,
4534     "B", "Jail persistence");
4535 #ifdef VIMAGE
4536 SYSCTL_JAIL_PARAM(, vnet, CTLTYPE_INT | CTLFLAG_RDTUN,
4537     "E,jailsys", "Virtual network stack");
4538 #endif
4539 SYSCTL_JAIL_PARAM(, dying, CTLTYPE_INT | CTLFLAG_RD,
4540     "B", "Jail is in the process of shutting down");
4541 
4542 SYSCTL_JAIL_PARAM_NODE(children, "Number of child jails");
4543 SYSCTL_JAIL_PARAM(_children, cur, CTLTYPE_INT | CTLFLAG_RD,
4544     "I", "Current number of child jails");
4545 SYSCTL_JAIL_PARAM(_children, max, CTLTYPE_INT | CTLFLAG_RW,
4546     "I", "Maximum number of child jails");
4547 
4548 SYSCTL_JAIL_PARAM_SYS_NODE(host, CTLFLAG_RW, "Jail host info");
4549 SYSCTL_JAIL_PARAM_STRING(_host, hostname, CTLFLAG_RW, MAXHOSTNAMELEN,
4550     "Jail hostname");
4551 SYSCTL_JAIL_PARAM_STRING(_host, domainname, CTLFLAG_RW, MAXHOSTNAMELEN,
4552     "Jail NIS domainname");
4553 SYSCTL_JAIL_PARAM_STRING(_host, hostuuid, CTLFLAG_RW, HOSTUUIDLEN,
4554     "Jail host UUID");
4555 SYSCTL_JAIL_PARAM(_host, hostid, CTLTYPE_ULONG | CTLFLAG_RW,
4556     "LU", "Jail host ID");
4557 
4558 SYSCTL_JAIL_PARAM_NODE(cpuset, "Jail cpuset");
4559 SYSCTL_JAIL_PARAM(_cpuset, id, CTLTYPE_INT | CTLFLAG_RD, "I", "Jail cpuset ID");
4560 
4561 #ifdef INET
4562 SYSCTL_JAIL_PARAM_SYS_NODE(ip4, CTLFLAG_RDTUN,
4563     "Jail IPv4 address virtualization");
4564 SYSCTL_JAIL_PARAM_STRUCT(_ip4, addr, CTLFLAG_RW, sizeof(struct in_addr),
4565     "S,in_addr,a", "Jail IPv4 addresses");
4566 SYSCTL_JAIL_PARAM(_ip4, saddrsel, CTLTYPE_INT | CTLFLAG_RW,
4567     "B", "Do (not) use IPv4 source address selection rather than the "
4568     "primary jail IPv4 address.");
4569 #endif
4570 #ifdef INET6
4571 SYSCTL_JAIL_PARAM_SYS_NODE(ip6, CTLFLAG_RDTUN,
4572     "Jail IPv6 address virtualization");
4573 SYSCTL_JAIL_PARAM_STRUCT(_ip6, addr, CTLFLAG_RW, sizeof(struct in6_addr),
4574     "S,in6_addr,a", "Jail IPv6 addresses");
4575 SYSCTL_JAIL_PARAM(_ip6, saddrsel, CTLTYPE_INT | CTLFLAG_RW,
4576     "B", "Do (not) use IPv6 source address selection rather than the "
4577     "primary jail IPv6 address.");
4578 #endif
4579 
4580 SYSCTL_JAIL_PARAM_NODE(allow, "Jail permission flags");
4581 SYSCTL_JAIL_PARAM(_allow, set_hostname, CTLTYPE_INT | CTLFLAG_RW,
4582     "B", "Jail may set hostname");
4583 SYSCTL_JAIL_PARAM(_allow, sysvipc, CTLTYPE_INT | CTLFLAG_RW,
4584     "B", "Jail may use SYSV IPC");
4585 SYSCTL_JAIL_PARAM(_allow, raw_sockets, CTLTYPE_INT | CTLFLAG_RW,
4586     "B", "Jail may create raw sockets");
4587 SYSCTL_JAIL_PARAM(_allow, chflags, CTLTYPE_INT | CTLFLAG_RW,
4588     "B", "Jail may alter system file flags");
4589 SYSCTL_JAIL_PARAM(_allow, quotas, CTLTYPE_INT | CTLFLAG_RW,
4590     "B", "Jail may set file quotas");
4591 SYSCTL_JAIL_PARAM(_allow, socket_af, CTLTYPE_INT | CTLFLAG_RW,
4592     "B", "Jail may create sockets other than just UNIX/IPv4/IPv6/route");
4593 SYSCTL_JAIL_PARAM(_allow, mlock, CTLTYPE_INT | CTLFLAG_RW,
4594     "B", "Jail may lock (unlock) physical pages in memory");
4595 SYSCTL_JAIL_PARAM(_allow, reserved_ports, CTLTYPE_INT | CTLFLAG_RW,
4596     "B", "Jail may bind sockets to reserved ports");
4597 SYSCTL_JAIL_PARAM(_allow, read_msgbuf, CTLTYPE_INT | CTLFLAG_RW,
4598     "B", "Jail may read the kernel message buffer");
4599 SYSCTL_JAIL_PARAM(_allow, unprivileged_proc_debug, CTLTYPE_INT | CTLFLAG_RW,
4600     "B", "Unprivileged processes may use process debugging facilities");
4601 SYSCTL_JAIL_PARAM(_allow, suser, CTLTYPE_INT | CTLFLAG_RW,
4602     "B", "Processes in jail with uid 0 have privilege");
4603 #ifdef VIMAGE
4604 SYSCTL_JAIL_PARAM(_allow, nfsd, CTLTYPE_INT | CTLFLAG_RW,
4605     "B", "Mountd/nfsd may run in the jail");
4606 #endif
4607 
4608 SYSCTL_JAIL_PARAM_SUBNODE(allow, mount, "Jail mount/unmount permission flags");
4609 SYSCTL_JAIL_PARAM(_allow_mount, , CTLTYPE_INT | CTLFLAG_RW,
4610     "B", "Jail may mount/unmount jail-friendly file systems in general");
4611 
4612 /*
4613  * Add a dynamic parameter allow.<name>, or allow.<prefix>.<name>.  Return
4614  * its associated bit in the pr_allow bitmask, or zero if the parameter was
4615  * not created.
4616  */
4617 unsigned
prison_add_allow(const char * prefix,const char * name,const char * prefix_descr,const char * descr)4618 prison_add_allow(const char *prefix, const char *name, const char *prefix_descr,
4619     const char *descr)
4620 {
4621 	struct bool_flags *bf;
4622 	struct sysctl_oid *parent;
4623 	char *allow_name, *allow_noname, *allowed;
4624 #ifndef NO_SYSCTL_DESCR
4625 	char *descr_deprecated;
4626 #endif
4627 	u_int allow_flag;
4628 
4629 	if (prefix
4630 	    ? asprintf(&allow_name, M_PRISON, "allow.%s.%s", prefix, name)
4631 		< 0 ||
4632 	      asprintf(&allow_noname, M_PRISON, "allow.%s.no%s", prefix, name)
4633 		< 0
4634 	    : asprintf(&allow_name, M_PRISON, "allow.%s", name) < 0 ||
4635 	      asprintf(&allow_noname, M_PRISON, "allow.no%s", name) < 0) {
4636 		free(allow_name, M_PRISON);
4637 		return 0;
4638 	}
4639 
4640 	/*
4641 	 * See if this parameter has already beed added, i.e. a module was
4642 	 * previously loaded/unloaded.
4643 	 */
4644 	mtx_lock(&prison0.pr_mtx);
4645 	for (bf = pr_flag_allow;
4646 	     bf < pr_flag_allow + nitems(pr_flag_allow) &&
4647 		atomic_load_int(&bf->flag) != 0;
4648 	     bf++) {
4649 		if (strcmp(bf->name, allow_name) == 0) {
4650 			allow_flag = bf->flag;
4651 			goto no_add;
4652 		}
4653 	}
4654 
4655 	/*
4656 	 * Find a free bit in pr_allow_all, failing if there are none
4657 	 * (which shouldn't happen as long as we keep track of how many
4658 	 * potential dynamic flags exist).
4659 	 */
4660 	for (allow_flag = 1;; allow_flag <<= 1) {
4661 		if (allow_flag == 0)
4662 			goto no_add;
4663 		if ((pr_allow_all & allow_flag) == 0)
4664 			break;
4665 	}
4666 
4667 	/* Note the parameter in the next open slot in pr_flag_allow. */
4668 	for (bf = pr_flag_allow; ; bf++) {
4669 		if (bf == pr_flag_allow + nitems(pr_flag_allow)) {
4670 			/* This should never happen, but is not fatal. */
4671 			allow_flag = 0;
4672 			goto no_add;
4673 		}
4674 		if (atomic_load_int(&bf->flag) == 0)
4675 			break;
4676 	}
4677 	bf->name = allow_name;
4678 	bf->noname = allow_noname;
4679 	pr_allow_all |= allow_flag;
4680 	/*
4681 	 * prison0 always has permission for the new parameter.
4682 	 * Other jails must have it granted to them.
4683 	 */
4684 	prison0.pr_allow |= allow_flag;
4685 	/* The flag indicates a valid entry, so make sure it is set last. */
4686 	atomic_store_rel_int(&bf->flag, allow_flag);
4687 	mtx_unlock(&prison0.pr_mtx);
4688 
4689 	/*
4690 	 * Create sysctls for the parameter, and the back-compat global
4691 	 * permission.
4692 	 */
4693 	parent = prefix
4694 	    ? SYSCTL_ADD_NODE(NULL,
4695 		  SYSCTL_CHILDREN(&sysctl___security_jail_param_allow),
4696 		  OID_AUTO, prefix, CTLFLAG_MPSAFE, 0, prefix_descr)
4697 	    : &sysctl___security_jail_param_allow;
4698 	(void)SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(parent), OID_AUTO,
4699 	    name, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4700 	    NULL, 0, sysctl_jail_param, "B", descr);
4701 	if ((prefix
4702 	     ? asprintf(&allowed, M_TEMP, "%s_%s_allowed", prefix, name)
4703 	     : asprintf(&allowed, M_TEMP, "%s_allowed", name)) >= 0) {
4704 #ifndef NO_SYSCTL_DESCR
4705 		(void)asprintf(&descr_deprecated, M_TEMP, "%s (deprecated)",
4706 		    descr);
4707 #endif
4708 		(void)SYSCTL_ADD_PROC(NULL,
4709 		    SYSCTL_CHILDREN(&sysctl___security_jail), OID_AUTO, allowed,
4710 		    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, NULL, allow_flag,
4711 		    sysctl_jail_default_allow, "I", descr_deprecated);
4712 #ifndef NO_SYSCTL_DESCR
4713 		free(descr_deprecated, M_TEMP);
4714 #endif
4715 		free(allowed, M_TEMP);
4716 	}
4717 	return allow_flag;
4718 
4719  no_add:
4720 	mtx_unlock(&prison0.pr_mtx);
4721 	free(allow_name, M_PRISON);
4722 	free(allow_noname, M_PRISON);
4723 	return allow_flag;
4724 }
4725 
4726 /*
4727  * The VFS system will register jail-aware filesystems here.  They each get
4728  * a parameter allow.mount.xxxfs and a flag to check when a jailed user
4729  * attempts to mount.
4730  */
4731 void
prison_add_vfs(struct vfsconf * vfsp)4732 prison_add_vfs(struct vfsconf *vfsp)
4733 {
4734 #ifdef NO_SYSCTL_DESCR
4735 
4736 	vfsp->vfc_prison_flag = prison_add_allow("mount", vfsp->vfc_name,
4737 	    NULL, NULL);
4738 #else
4739 	char *descr;
4740 
4741 	(void)asprintf(&descr, M_TEMP, "Jail may mount the %s file system",
4742 	    vfsp->vfc_name);
4743 	vfsp->vfc_prison_flag = prison_add_allow("mount", vfsp->vfc_name,
4744 	    NULL, descr);
4745 	free(descr, M_TEMP);
4746 #endif
4747 }
4748 
4749 #ifdef RACCT
4750 void
prison_racct_foreach(void (* callback)(struct racct * racct,void * arg2,void * arg3),void (* pre)(void),void (* post)(void),void * arg2,void * arg3)4751 prison_racct_foreach(void (*callback)(struct racct *racct,
4752     void *arg2, void *arg3), void (*pre)(void), void (*post)(void),
4753     void *arg2, void *arg3)
4754 {
4755 	struct prison_racct *prr;
4756 
4757 	ASSERT_RACCT_ENABLED();
4758 
4759 	sx_slock(&allprison_lock);
4760 	if (pre != NULL)
4761 		(pre)();
4762 	LIST_FOREACH(prr, &allprison_racct, prr_next)
4763 		(callback)(prr->prr_racct, arg2, arg3);
4764 	if (post != NULL)
4765 		(post)();
4766 	sx_sunlock(&allprison_lock);
4767 }
4768 
4769 static struct prison_racct *
prison_racct_find_locked(const char * name)4770 prison_racct_find_locked(const char *name)
4771 {
4772 	struct prison_racct *prr;
4773 
4774 	ASSERT_RACCT_ENABLED();
4775 	sx_assert(&allprison_lock, SA_XLOCKED);
4776 
4777 	if (name[0] == '\0' || strlen(name) >= MAXHOSTNAMELEN)
4778 		return (NULL);
4779 
4780 	LIST_FOREACH(prr, &allprison_racct, prr_next) {
4781 		if (strcmp(name, prr->prr_name) != 0)
4782 			continue;
4783 
4784 		/* Found prison_racct with a matching name? */
4785 		prison_racct_hold(prr);
4786 		return (prr);
4787 	}
4788 
4789 	/* Add new prison_racct. */
4790 	prr = malloc(sizeof(*prr), M_PRISON_RACCT, M_ZERO | M_WAITOK);
4791 	racct_create(&prr->prr_racct);
4792 
4793 	strcpy(prr->prr_name, name);
4794 	refcount_init(&prr->prr_refcount, 1);
4795 	LIST_INSERT_HEAD(&allprison_racct, prr, prr_next);
4796 
4797 	return (prr);
4798 }
4799 
4800 struct prison_racct *
prison_racct_find(const char * name)4801 prison_racct_find(const char *name)
4802 {
4803 	struct prison_racct *prr;
4804 
4805 	ASSERT_RACCT_ENABLED();
4806 
4807 	sx_xlock(&allprison_lock);
4808 	prr = prison_racct_find_locked(name);
4809 	sx_xunlock(&allprison_lock);
4810 	return (prr);
4811 }
4812 
4813 void
prison_racct_hold(struct prison_racct * prr)4814 prison_racct_hold(struct prison_racct *prr)
4815 {
4816 
4817 	ASSERT_RACCT_ENABLED();
4818 
4819 	refcount_acquire(&prr->prr_refcount);
4820 }
4821 
4822 static void
prison_racct_free_locked(struct prison_racct * prr)4823 prison_racct_free_locked(struct prison_racct *prr)
4824 {
4825 
4826 	ASSERT_RACCT_ENABLED();
4827 	sx_assert(&allprison_lock, SA_XLOCKED);
4828 
4829 	if (refcount_release(&prr->prr_refcount)) {
4830 		racct_destroy(&prr->prr_racct);
4831 		LIST_REMOVE(prr, prr_next);
4832 		free(prr, M_PRISON_RACCT);
4833 	}
4834 }
4835 
4836 void
prison_racct_free(struct prison_racct * prr)4837 prison_racct_free(struct prison_racct *prr)
4838 {
4839 
4840 	ASSERT_RACCT_ENABLED();
4841 	sx_assert(&allprison_lock, SA_UNLOCKED);
4842 
4843 	if (refcount_release_if_not_last(&prr->prr_refcount))
4844 		return;
4845 
4846 	sx_xlock(&allprison_lock);
4847 	prison_racct_free_locked(prr);
4848 	sx_xunlock(&allprison_lock);
4849 }
4850 
4851 static void
prison_racct_attach(struct prison * pr)4852 prison_racct_attach(struct prison *pr)
4853 {
4854 	struct prison_racct *prr;
4855 
4856 	ASSERT_RACCT_ENABLED();
4857 	sx_assert(&allprison_lock, SA_XLOCKED);
4858 
4859 	prr = prison_racct_find_locked(pr->pr_name);
4860 	KASSERT(prr != NULL, ("cannot find prison_racct"));
4861 
4862 	pr->pr_prison_racct = prr;
4863 }
4864 
4865 /*
4866  * Handle jail renaming.  From the racct point of view, renaming means
4867  * moving from one prison_racct to another.
4868  */
4869 static void
prison_racct_modify(struct prison * pr)4870 prison_racct_modify(struct prison *pr)
4871 {
4872 #ifdef RCTL
4873 	struct proc *p;
4874 	struct ucred *cred;
4875 #endif
4876 	struct prison_racct *oldprr;
4877 
4878 	ASSERT_RACCT_ENABLED();
4879 
4880 	sx_slock(&allproc_lock);
4881 	sx_xlock(&allprison_lock);
4882 
4883 	if (strcmp(pr->pr_name, pr->pr_prison_racct->prr_name) == 0) {
4884 		sx_xunlock(&allprison_lock);
4885 		sx_sunlock(&allproc_lock);
4886 		return;
4887 	}
4888 
4889 	oldprr = pr->pr_prison_racct;
4890 	pr->pr_prison_racct = NULL;
4891 
4892 	prison_racct_attach(pr);
4893 
4894 	/*
4895 	 * Move resource utilisation records.
4896 	 */
4897 	racct_move(pr->pr_prison_racct->prr_racct, oldprr->prr_racct);
4898 
4899 #ifdef RCTL
4900 	/*
4901 	 * Force rctl to reattach rules to processes.
4902 	 */
4903 	FOREACH_PROC_IN_SYSTEM(p) {
4904 		PROC_LOCK(p);
4905 		cred = crhold(p->p_ucred);
4906 		PROC_UNLOCK(p);
4907 		rctl_proc_ucred_changed(p, cred);
4908 		crfree(cred);
4909 	}
4910 #endif
4911 
4912 	sx_sunlock(&allproc_lock);
4913 	prison_racct_free_locked(oldprr);
4914 	sx_xunlock(&allprison_lock);
4915 }
4916 
4917 static void
prison_racct_detach(struct prison * pr)4918 prison_racct_detach(struct prison *pr)
4919 {
4920 
4921 	ASSERT_RACCT_ENABLED();
4922 	sx_assert(&allprison_lock, SA_UNLOCKED);
4923 
4924 	if (pr->pr_prison_racct == NULL)
4925 		return;
4926 	prison_racct_free(pr->pr_prison_racct);
4927 	pr->pr_prison_racct = NULL;
4928 }
4929 #endif /* RACCT */
4930 
4931 #ifdef DDB
4932 
4933 static void
db_show_prison(struct prison * pr)4934 db_show_prison(struct prison *pr)
4935 {
4936 	struct bool_flags *bf;
4937 	struct jailsys_flags *jsf;
4938 #if defined(INET) || defined(INET6)
4939 	int ii;
4940 	struct prison_ip *pip;
4941 #endif
4942 	unsigned f;
4943 #ifdef INET
4944 	char ip4buf[INET_ADDRSTRLEN];
4945 #endif
4946 #ifdef INET6
4947 	char ip6buf[INET6_ADDRSTRLEN];
4948 #endif
4949 
4950 	db_printf("prison %p:\n", pr);
4951 	db_printf(" jid             = %d\n", pr->pr_id);
4952 	db_printf(" name            = %s\n", pr->pr_name);
4953 	db_printf(" parent          = %p\n", pr->pr_parent);
4954 	db_printf(" ref             = %d\n", pr->pr_ref);
4955 	db_printf(" uref            = %d\n", pr->pr_uref);
4956 	db_printf(" state           = %s\n",
4957 	    pr->pr_state == PRISON_STATE_ALIVE ? "alive" :
4958 	    pr->pr_state == PRISON_STATE_DYING ? "dying" :
4959 	    "invalid");
4960 	db_printf(" path            = %s\n", pr->pr_path);
4961 	db_printf(" cpuset          = %d\n", pr->pr_cpuset
4962 	    ? pr->pr_cpuset->cs_id : -1);
4963 #ifdef VIMAGE
4964 	db_printf(" vnet            = %p\n", pr->pr_vnet);
4965 #endif
4966 	db_printf(" root            = %p\n", pr->pr_root);
4967 	db_printf(" securelevel     = %d\n", pr->pr_securelevel);
4968 	db_printf(" devfs_rsnum     = %d\n", pr->pr_devfs_rsnum);
4969 	db_printf(" children.max    = %d\n", pr->pr_childmax);
4970 	db_printf(" children.cur    = %d\n", pr->pr_childcount);
4971 	db_printf(" child           = %p\n", LIST_FIRST(&pr->pr_children));
4972 	db_printf(" sibling         = %p\n", LIST_NEXT(pr, pr_sibling));
4973 	db_printf(" flags           = 0x%x", pr->pr_flags);
4974 	for (bf = pr_flag_bool; bf < pr_flag_bool + nitems(pr_flag_bool); bf++)
4975 		if (pr->pr_flags & bf->flag)
4976 			db_printf(" %s", bf->name);
4977 	for (jsf = pr_flag_jailsys;
4978 	     jsf < pr_flag_jailsys + nitems(pr_flag_jailsys);
4979 	     jsf++) {
4980 		f = pr->pr_flags & (jsf->disable | jsf->new);
4981 		db_printf(" %-16s= %s\n", jsf->name,
4982 		    (f != 0 && f == jsf->disable) ? "disable"
4983 		    : (f == jsf->new) ? "new"
4984 		    : "inherit");
4985 	}
4986 	db_printf(" allow           = 0x%x", pr->pr_allow);
4987 	for (bf = pr_flag_allow;
4988 	     bf < pr_flag_allow + nitems(pr_flag_allow) &&
4989 		atomic_load_int(&bf->flag) != 0;
4990 	     bf++)
4991 		if (pr->pr_allow & bf->flag)
4992 			db_printf(" %s", bf->name);
4993 	db_printf("\n");
4994 	db_printf(" enforce_statfs  = %d\n", pr->pr_enforce_statfs);
4995 	db_printf(" host.hostname   = %s\n", pr->pr_hostname);
4996 	db_printf(" host.domainname = %s\n", pr->pr_domainname);
4997 	db_printf(" host.hostuuid   = %s\n", pr->pr_hostuuid);
4998 	db_printf(" host.hostid     = %lu\n", pr->pr_hostid);
4999 #ifdef INET
5000 	if ((pip = pr->pr_addrs[PR_INET]) != NULL) {
5001 		db_printf(" ip4s            = %d\n", pip->ips);
5002 		for (ii = 0; ii < pip->ips; ii++)
5003 			db_printf(" %s %s\n",
5004 			    ii == 0 ? "ip4.addr        =" : "                 ",
5005 			    inet_ntoa_r(
5006 			    *(const struct in_addr *)PR_IP(pip, PR_INET, ii),
5007 			    ip4buf));
5008 	}
5009 #endif
5010 #ifdef INET6
5011 	if ((pip = pr->pr_addrs[PR_INET6]) != NULL) {
5012 		db_printf(" ip6s            = %d\n", pip->ips);
5013 		for (ii = 0; ii < pip->ips; ii++)
5014 			db_printf(" %s %s\n",
5015 			    ii == 0 ? "ip6.addr        =" : "                 ",
5016 			    ip6_sprintf(ip6buf,
5017 			    (const struct in6_addr *)PR_IP(pip, PR_INET6, ii)));
5018 	}
5019 #endif
5020 }
5021 
DB_SHOW_COMMAND(prison,db_show_prison_command)5022 DB_SHOW_COMMAND(prison, db_show_prison_command)
5023 {
5024 	struct prison *pr;
5025 
5026 	if (!have_addr) {
5027 		/*
5028 		 * Show all prisons in the list, and prison0 which is not
5029 		 * listed.
5030 		 */
5031 		db_show_prison(&prison0);
5032 		if (!db_pager_quit) {
5033 			TAILQ_FOREACH(pr, &allprison, pr_list) {
5034 				db_show_prison(pr);
5035 				if (db_pager_quit)
5036 					break;
5037 			}
5038 		}
5039 		return;
5040 	}
5041 
5042 	if (addr == 0)
5043 		pr = &prison0;
5044 	else {
5045 		/* Look for a prison with the ID and with references. */
5046 		TAILQ_FOREACH(pr, &allprison, pr_list)
5047 			if (pr->pr_id == addr && pr->pr_ref > 0)
5048 				break;
5049 		if (pr == NULL)
5050 			/* Look again, without requiring a reference. */
5051 			TAILQ_FOREACH(pr, &allprison, pr_list)
5052 				if (pr->pr_id == addr)
5053 					break;
5054 		if (pr == NULL)
5055 			/* Assume address points to a valid prison. */
5056 			pr = (struct prison *)addr;
5057 	}
5058 	db_show_prison(pr);
5059 }
5060 
5061 #endif /* DDB */
5062