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/file.h>
43 #include <sys/sysproto.h>
44 #include <sys/malloc.h>
45 #include <sys/osd.h>
46 #include <sys/priv.h>
47 #include <sys/proc.h>
48 #include <sys/epoch.h>
49 #include <sys/event.h>
50 #include <sys/taskqueue.h>
51 #include <sys/fcntl.h>
52 #include <sys/jail.h>
53 #include <sys/jaildesc.h>
54 #include <sys/linker.h>
55 #include <sys/lock.h>
56 #include <sys/mman.h>
57 #include <sys/mutex.h>
58 #include <sys/racct.h>
59 #include <sys/rctl.h>
60 #include <sys/refcount.h>
61 #include <sys/sx.h>
62 #include <sys/sysent.h>
63 #include <sys/namei.h>
64 #include <sys/mount.h>
65 #include <sys/queue.h>
66 #include <sys/socket.h>
67 #include <sys/syscallsubr.h>
68 #include <sys/sysctl.h>
69 #include <sys/uuid.h>
70 #include <sys/vnode.h>
71
72 #include <net/if.h>
73 #include <net/vnet.h>
74
75 #include <netinet/in.h>
76
77 #ifdef DDB
78 #include <ddb/ddb.h>
79 #endif /* DDB */
80
81 #include <security/mac/mac_framework.h>
82
83 #define PRISON0_HOSTUUID_MODULE "hostuuid"
84
85 MALLOC_DEFINE(M_PRISON, "prison", "Prison structures");
86 static MALLOC_DEFINE(M_PRISON_RACCT, "prison_racct", "Prison racct structures");
87
88 /* Keep struct prison prison0 and some code in kern_jail_set() readable. */
89 #ifdef INET
90 #ifdef INET6
91 #define _PR_IP_SADDRSEL PR_IP4_SADDRSEL|PR_IP6_SADDRSEL
92 #else
93 #define _PR_IP_SADDRSEL PR_IP4_SADDRSEL
94 #endif
95 #else /* !INET */
96 #ifdef INET6
97 #define _PR_IP_SADDRSEL PR_IP6_SADDRSEL
98 #else
99 #define _PR_IP_SADDRSEL 0
100 #endif
101 #endif
102
103 /* prison0 describes what is "real" about the system. */
104 struct prison prison0 = {
105 .pr_id = 0,
106 .pr_name = "0",
107 .pr_ref = 1,
108 .pr_uref = 1,
109 .pr_path = "/",
110 .pr_securelevel = -1,
111 .pr_devfs_rsnum = 0,
112 .pr_state = PRISON_STATE_ALIVE,
113 .pr_childmax = JAIL_MAX,
114 .pr_hostuuid = DEFAULT_HOSTUUID,
115 .pr_children = LIST_HEAD_INITIALIZER(prison0.pr_children),
116 #ifdef VIMAGE
117 .pr_flags = PR_HOST|PR_VNET|_PR_IP_SADDRSEL,
118 #else
119 .pr_flags = PR_HOST|_PR_IP_SADDRSEL,
120 #endif
121 .pr_allow = PR_ALLOW_PRISON0,
122 };
123 _Static_assert((PR_ALLOW_PRISON0 & ~PR_ALLOW_ALL_STATIC) == 0,
124 "Bits enabled in PR_ALLOW_PRISON0 that are not statically reserved");
125
126 MTX_SYSINIT(prison0, &prison0.pr_mtx, "jail mutex", MTX_DEF);
127
128 struct bool_flags {
129 const char *name;
130 const char *noname;
131 volatile u_int flag;
132 };
133 struct jailsys_flags {
134 const char *name;
135 unsigned disable;
136 unsigned new;
137 };
138
139 /*
140 * Handle jail teardown in a dedicated thread to avoid deadlocks from
141 * vnet_destroy().
142 */
143 TASKQUEUE_DEFINE_THREAD(jail_remove);
144
145 /* allprison, allprison_racct and lastprid are protected by allprison_lock. */
146 struct sx allprison_lock;
147 SX_SYSINIT(allprison_lock, &allprison_lock, "allprison");
148 struct prisonlist allprison = TAILQ_HEAD_INITIALIZER(allprison);
149 LIST_HEAD(, prison_racct) allprison_racct;
150 int lastprid = 0;
151 int lastdeadid = 0;
152
153 static int get_next_prid(struct prison **insprp);
154 static int get_next_deadid(struct prison **insprp);
155 static int do_jail_attach(struct thread *td, struct prison *pr, int drflags);
156 static void prison_complete(void *context, int pending);
157 static void prison_deref(struct prison *pr, int flags);
158 static void prison_deref_kill(struct prison *pr, struct prisonlist *freeprison);
159 static int prison_lock_xlock(struct prison *pr, int flags);
160 static void prison_cleanup_locked(struct prison *pr);
161 static void prison_cleanup_unlocked(struct prison *pr);
162 static void prison_free_not_last(struct prison *pr);
163 static void prison_proc_free_not_last(struct prison *pr);
164 static void prison_proc_relink(struct prison *opr, struct prison *npr,
165 struct proc *p);
166 static void prison_set_allow_locked(struct prison *pr, unsigned flag,
167 int enable);
168 static char *prison_path(struct prison *pr1, struct prison *pr2);
169 #ifdef RACCT
170 static void prison_racct_attach(struct prison *pr);
171 static void prison_racct_modify(struct prison *pr);
172 static void prison_racct_detach(struct prison *pr);
173 #endif
174 static void prison_knote(struct prison *pr, long hint);
175
176 /* Flags for prison_deref */
177 #define PD_DEREF 0x01 /* Decrement pr_ref */
178 #define PD_DEUREF 0x02 /* Decrement pr_uref */
179 #define PD_KILL 0x04 /* Remove jail, kill processes, etc */
180 #define PD_LOCKED 0x10 /* pr_mtx is held */
181 #define PD_LIST_SLOCKED 0x20 /* allprison_lock is held shared */
182 #define PD_LIST_XLOCKED 0x40 /* allprison_lock is held exclusive */
183 #define PD_OP_FLAGS 0x07 /* Operation flags */
184 #define PD_LOCK_FLAGS 0x70 /* Lock status flags */
185
186 /*
187 * Parameter names corresponding to PR_* flag values. Size values are for kvm
188 * as we cannot figure out the size of a sparse array, or an array without a
189 * terminating entry.
190 */
191 static struct bool_flags pr_flag_bool[] = {
192 {"persist", "nopersist", PR_PERSIST},
193 #ifdef INET
194 {"ip4.saddrsel", "ip4.nosaddrsel", PR_IP4_SADDRSEL},
195 #endif
196 #ifdef INET6
197 {"ip6.saddrsel", "ip6.nosaddrsel", PR_IP6_SADDRSEL},
198 #endif
199 };
200 const size_t pr_flag_bool_size = sizeof(pr_flag_bool);
201
202 static struct jailsys_flags pr_flag_jailsys[] = {
203 {"host", 0, PR_HOST},
204 #ifdef VIMAGE
205 {"vnet", 0, PR_VNET},
206 #endif
207 #ifdef INET
208 {"ip4", PR_IP4_USER, PR_IP4_USER},
209 #endif
210 #ifdef INET6
211 {"ip6", PR_IP6_USER, PR_IP6_USER},
212 #endif
213 };
214 const size_t pr_flag_jailsys_size = sizeof(pr_flag_jailsys);
215
216 /*
217 * Make this array full-size so dynamic parameters can be added.
218 * It is protected by prison0.mtx, but lockless reading is allowed
219 * with an atomic check of the flag values.
220 */
221 static struct bool_flags pr_flag_allow[NBBY * NBPW] = {
222 {"allow.set_hostname", "allow.noset_hostname", PR_ALLOW_SET_HOSTNAME},
223 {"allow.sysvipc", "allow.nosysvipc", PR_ALLOW_SYSVIPC},
224 {"allow.raw_sockets", "allow.noraw_sockets", PR_ALLOW_RAW_SOCKETS},
225 {"allow.chflags", "allow.nochflags", PR_ALLOW_CHFLAGS},
226 {"allow.mount", "allow.nomount", PR_ALLOW_MOUNT},
227 {"allow.quotas", "allow.noquotas", PR_ALLOW_QUOTAS},
228 {"allow.socket_af", "allow.nosocket_af", PR_ALLOW_SOCKET_AF},
229 {"allow.mlock", "allow.nomlock", PR_ALLOW_MLOCK},
230 {"allow.reserved_ports", "allow.noreserved_ports",
231 PR_ALLOW_RESERVED_PORTS},
232 {"allow.read_msgbuf", "allow.noread_msgbuf", PR_ALLOW_READ_MSGBUF},
233 {"allow.unprivileged_proc_debug", "allow.nounprivileged_proc_debug",
234 PR_ALLOW_UNPRIV_DEBUG},
235 {"allow.suser", "allow.nosuser", PR_ALLOW_SUSER},
236 #ifdef VIMAGE
237 {"allow.nfsd", "allow.nonfsd", PR_ALLOW_NFSD},
238 #endif
239 {"allow.extattr", "allow.noextattr", PR_ALLOW_EXTATTR},
240 {"allow.adjtime", "allow.noadjtime", PR_ALLOW_ADJTIME},
241 {"allow.settime", "allow.nosettime", PR_ALLOW_SETTIME},
242 {"allow.routing", "allow.norouting", PR_ALLOW_ROUTING},
243 {"allow.unprivileged_parent_tampering",
244 "allow.nounprivileged_parent_tampering",
245 PR_ALLOW_UNPRIV_PARENT_TAMPER},
246 #ifdef AUDIT
247 {"allow.setaudit", "allow.nosetaudit", PR_ALLOW_SETAUDIT},
248 #endif
249 };
250 static unsigned pr_allow_all = PR_ALLOW_ALL_STATIC;
251 const size_t pr_flag_allow_size = sizeof(pr_flag_allow);
252
253 #define JAIL_DEFAULT_ALLOW (PR_ALLOW_SET_HOSTNAME | \
254 PR_ALLOW_RESERVED_PORTS | \
255 PR_ALLOW_UNPRIV_DEBUG | \
256 PR_ALLOW_SUSER)
257 #define JAIL_DEFAULT_ENFORCE_STATFS 2
258 #define JAIL_DEFAULT_DEVFS_RSNUM 0
259 static unsigned jail_default_allow = JAIL_DEFAULT_ALLOW;
260 static int jail_default_enforce_statfs = JAIL_DEFAULT_ENFORCE_STATFS;
261 static int jail_default_devfs_rsnum = JAIL_DEFAULT_DEVFS_RSNUM;
262 #if defined(INET) || defined(INET6)
263 static unsigned jail_max_af_ips = 255;
264 #endif
265
266 /*
267 * Initialize the parts of prison0 that can't be static-initialized with
268 * constants. This is called from proc0_init() after creating thread0 cpuset.
269 */
270 void
prison0_init(void)271 prison0_init(void)
272 {
273 uint8_t *file, *data;
274 size_t size;
275 char buf[sizeof(prison0.pr_hostuuid)];
276 bool valid;
277
278 prison0.pr_cpuset = cpuset_ref(thread0.td_cpuset);
279 prison0.pr_osreldate = osreldate;
280 strlcpy(prison0.pr_osrelease, osrelease, sizeof(prison0.pr_osrelease));
281
282 /* If we have a preloaded hostuuid, use it. */
283 file = preload_search_by_type(PRISON0_HOSTUUID_MODULE);
284 if (file != NULL) {
285 data = preload_fetch_addr(file);
286 size = preload_fetch_size(file);
287 if (data != NULL) {
288 /*
289 * The preloaded data may include trailing whitespace, almost
290 * certainly a newline; skip over any whitespace or
291 * non-printable characters to be safe.
292 */
293 while (size > 0 && data[size - 1] <= 0x20) {
294 size--;
295 }
296
297 valid = false;
298
299 /*
300 * Not NUL-terminated when passed from loader, but
301 * validate_uuid requires that due to using sscanf (as
302 * does the subsequent strlcpy, since it still reads
303 * past the given size to return the true length);
304 * bounce to a temporary buffer to fix.
305 */
306 if (size >= sizeof(buf))
307 goto done;
308
309 memcpy(buf, data, size);
310 buf[size] = '\0';
311
312 if (validate_uuid(buf, size, NULL, 0) != 0)
313 goto done;
314
315 valid = true;
316 (void)strlcpy(prison0.pr_hostuuid, buf,
317 sizeof(prison0.pr_hostuuid));
318
319 done:
320 if (bootverbose && !valid) {
321 printf("hostuuid: preload data malformed: '%.*s'\n",
322 (int)size, data);
323 }
324 }
325 }
326 if (bootverbose)
327 printf("hostuuid: using %s\n", prison0.pr_hostuuid);
328 }
329
330 /*
331 * struct jail_args {
332 * struct jail *jail;
333 * };
334 */
335 int
sys_jail(struct thread * td,struct jail_args * uap)336 sys_jail(struct thread *td, struct jail_args *uap)
337 {
338 uint32_t version;
339 int error;
340 struct jail j;
341
342 error = copyin(uap->jail, &version, sizeof(uint32_t));
343 if (error)
344 return (error);
345
346 switch (version) {
347 case 0:
348 {
349 struct jail_v0 j0;
350
351 /* FreeBSD single IPv4 jails. */
352 bzero(&j, sizeof(struct jail));
353 error = copyin(uap->jail, &j0, sizeof(struct jail_v0));
354 if (error)
355 return (error);
356 j.version = j0.version;
357 j.path = j0.path;
358 j.hostname = j0.hostname;
359 j.ip4s = htonl(j0.ip_number); /* jail_v0 is host order */
360 break;
361 }
362
363 case 1:
364 /*
365 * Version 1 was used by multi-IPv4 jail implementations
366 * that never made it into the official kernel.
367 */
368 return (EINVAL);
369
370 case 2: /* JAIL_API_VERSION */
371 /* FreeBSD multi-IPv4/IPv6,noIP jails. */
372 error = copyin(uap->jail, &j, sizeof(struct jail));
373 if (error)
374 return (error);
375 break;
376
377 default:
378 /* Sci-Fi jails are not supported, sorry. */
379 return (EINVAL);
380 }
381 return (kern_jail(td, &j));
382 }
383
384 int
kern_jail(struct thread * td,struct jail * j)385 kern_jail(struct thread *td, struct jail *j)
386 {
387 struct iovec optiov[2 * (4 + nitems(pr_flag_allow)
388 #ifdef INET
389 + 1
390 #endif
391 #ifdef INET6
392 + 1
393 #endif
394 )];
395 struct uio opt;
396 char *u_path, *u_hostname, *u_name;
397 struct bool_flags *bf;
398 #ifdef INET
399 uint32_t ip4s;
400 struct in_addr *u_ip4;
401 #endif
402 #ifdef INET6
403 struct in6_addr *u_ip6;
404 #endif
405 size_t tmplen;
406 int error, enforce_statfs;
407
408 bzero(&optiov, sizeof(optiov));
409 opt.uio_iov = optiov;
410 opt.uio_iovcnt = 0;
411 opt.uio_offset = -1;
412 opt.uio_resid = -1;
413 opt.uio_segflg = UIO_SYSSPACE;
414 opt.uio_rw = UIO_READ;
415 opt.uio_td = td;
416
417 /* Set permissions for top-level jails from sysctls. */
418 if (!jailed(td->td_ucred)) {
419 for (bf = pr_flag_allow;
420 bf < pr_flag_allow + nitems(pr_flag_allow) &&
421 atomic_load_int(&bf->flag) != 0;
422 bf++) {
423 optiov[opt.uio_iovcnt].iov_base = __DECONST(char *,
424 (jail_default_allow & bf->flag)
425 ? bf->name : bf->noname);
426 optiov[opt.uio_iovcnt].iov_len =
427 strlen(optiov[opt.uio_iovcnt].iov_base) + 1;
428 opt.uio_iovcnt += 2;
429 }
430 optiov[opt.uio_iovcnt].iov_base = "enforce_statfs";
431 optiov[opt.uio_iovcnt].iov_len = sizeof("enforce_statfs");
432 opt.uio_iovcnt++;
433 enforce_statfs = jail_default_enforce_statfs;
434 optiov[opt.uio_iovcnt].iov_base = &enforce_statfs;
435 optiov[opt.uio_iovcnt].iov_len = sizeof(enforce_statfs);
436 opt.uio_iovcnt++;
437 }
438
439 tmplen = MAXPATHLEN + MAXHOSTNAMELEN + MAXHOSTNAMELEN;
440 #ifdef INET
441 ip4s = (j->version == 0) ? 1 : j->ip4s;
442 if (ip4s > jail_max_af_ips)
443 return (EINVAL);
444 tmplen += ip4s * sizeof(struct in_addr);
445 #else
446 if (j->ip4s > 0)
447 return (EINVAL);
448 #endif
449 #ifdef INET6
450 if (j->ip6s > jail_max_af_ips)
451 return (EINVAL);
452 tmplen += j->ip6s * sizeof(struct in6_addr);
453 #else
454 if (j->ip6s > 0)
455 return (EINVAL);
456 #endif
457 u_path = malloc(tmplen, M_TEMP, M_WAITOK);
458 u_hostname = u_path + MAXPATHLEN;
459 u_name = u_hostname + MAXHOSTNAMELEN;
460 #ifdef INET
461 u_ip4 = (struct in_addr *)(u_name + MAXHOSTNAMELEN);
462 #endif
463 #ifdef INET6
464 #ifdef INET
465 u_ip6 = (struct in6_addr *)(u_ip4 + ip4s);
466 #else
467 u_ip6 = (struct in6_addr *)(u_name + MAXHOSTNAMELEN);
468 #endif
469 #endif
470 optiov[opt.uio_iovcnt].iov_base = "path";
471 optiov[opt.uio_iovcnt].iov_len = sizeof("path");
472 opt.uio_iovcnt++;
473 optiov[opt.uio_iovcnt].iov_base = u_path;
474 error = copyinstr(j->path, u_path, MAXPATHLEN,
475 &optiov[opt.uio_iovcnt].iov_len);
476 if (error) {
477 free(u_path, M_TEMP);
478 return (error);
479 }
480 opt.uio_iovcnt++;
481 optiov[opt.uio_iovcnt].iov_base = "host.hostname";
482 optiov[opt.uio_iovcnt].iov_len = sizeof("host.hostname");
483 opt.uio_iovcnt++;
484 optiov[opt.uio_iovcnt].iov_base = u_hostname;
485 error = copyinstr(j->hostname, u_hostname, MAXHOSTNAMELEN,
486 &optiov[opt.uio_iovcnt].iov_len);
487 if (error) {
488 free(u_path, M_TEMP);
489 return (error);
490 }
491 opt.uio_iovcnt++;
492 if (j->jailname != NULL) {
493 optiov[opt.uio_iovcnt].iov_base = "name";
494 optiov[opt.uio_iovcnt].iov_len = sizeof("name");
495 opt.uio_iovcnt++;
496 optiov[opt.uio_iovcnt].iov_base = u_name;
497 error = copyinstr(j->jailname, u_name, MAXHOSTNAMELEN,
498 &optiov[opt.uio_iovcnt].iov_len);
499 if (error) {
500 free(u_path, M_TEMP);
501 return (error);
502 }
503 opt.uio_iovcnt++;
504 }
505 #ifdef INET
506 optiov[opt.uio_iovcnt].iov_base = "ip4.addr";
507 optiov[opt.uio_iovcnt].iov_len = sizeof("ip4.addr");
508 opt.uio_iovcnt++;
509 optiov[opt.uio_iovcnt].iov_base = u_ip4;
510 optiov[opt.uio_iovcnt].iov_len = ip4s * sizeof(struct in_addr);
511 if (j->version == 0)
512 u_ip4->s_addr = j->ip4s;
513 else {
514 error = copyin(j->ip4, u_ip4, optiov[opt.uio_iovcnt].iov_len);
515 if (error) {
516 free(u_path, M_TEMP);
517 return (error);
518 }
519 }
520 opt.uio_iovcnt++;
521 #endif
522 #ifdef INET6
523 optiov[opt.uio_iovcnt].iov_base = "ip6.addr";
524 optiov[opt.uio_iovcnt].iov_len = sizeof("ip6.addr");
525 opt.uio_iovcnt++;
526 optiov[opt.uio_iovcnt].iov_base = u_ip6;
527 optiov[opt.uio_iovcnt].iov_len = j->ip6s * sizeof(struct in6_addr);
528 error = copyin(j->ip6, u_ip6, optiov[opt.uio_iovcnt].iov_len);
529 if (error) {
530 free(u_path, M_TEMP);
531 return (error);
532 }
533 opt.uio_iovcnt++;
534 #endif
535 KASSERT(opt.uio_iovcnt <= nitems(optiov),
536 ("kern_jail: too many iovecs (%d)", opt.uio_iovcnt));
537 error = kern_jail_set(td, &opt, JAIL_CREATE | JAIL_ATTACH);
538 free(u_path, M_TEMP);
539 return (error);
540 }
541
542 /*
543 * struct jail_set_args {
544 * struct iovec *iovp;
545 * unsigned int iovcnt;
546 * int flags;
547 * };
548 */
549 int
sys_jail_set(struct thread * td,struct jail_set_args * uap)550 sys_jail_set(struct thread *td, struct jail_set_args *uap)
551 {
552 struct uio *auio;
553 int error;
554
555 /* Check that we have an even number of iovecs. */
556 if (uap->iovcnt & 1)
557 return (EINVAL);
558
559 error = copyinuio(uap->iovp, uap->iovcnt, &auio);
560 if (error)
561 return (error);
562 error = kern_jail_set(td, auio, uap->flags);
563 freeuio(auio);
564 return (error);
565 }
566
567 #if defined(INET) || defined(INET6)
568 typedef int prison_addr_cmp_t(const void *, const void *);
569 typedef bool prison_addr_valid_t(const void *);
570 static const struct pr_family {
571 size_t size;
572 prison_addr_cmp_t *cmp;
573 prison_addr_valid_t *valid;
574 int ip_flag;
575 } pr_families[PR_FAMILY_MAX] = {
576 #ifdef INET
577 [PR_INET] = {
578 .size = sizeof(struct in_addr),
579 .cmp = prison_qcmp_v4,
580 .valid = prison_valid_v4,
581 .ip_flag = PR_IP4_USER,
582 },
583 #endif
584 #ifdef INET6
585 [PR_INET6] = {
586 .size = sizeof(struct in6_addr),
587 .cmp = prison_qcmp_v6,
588 .valid = prison_valid_v6,
589 .ip_flag = PR_IP6_USER,
590 },
591 #endif
592 };
593
594 /*
595 * Network address lists (pr_addrs) allocation for jails. The addresses
596 * are accessed locklessly by the network stack, thus need to be protected by
597 * the network epoch.
598 */
599 struct prison_ip {
600 struct epoch_context ctx;
601 uint32_t ips;
602 #ifdef FUTURE_C
603 /*
604 * XXX Variable-length automatic arrays in union may be
605 * supported in future C.
606 */
607 union {
608 char pr_ip[];
609 struct in_addr pr_ip4[];
610 struct in6_addr pr_ip6[];
611 };
612 #else /* No future C :( */
613 char pr_ip[];
614 #endif
615 };
616
617 static char *
PR_IP(struct prison_ip * pip,const pr_family_t af,int idx)618 PR_IP(struct prison_ip *pip, const pr_family_t af, int idx)
619 {
620 MPASS(pip);
621 MPASS(af < PR_FAMILY_MAX);
622 MPASS(idx >= 0 && idx < pip->ips);
623
624 return (pip->pr_ip + pr_families[af].size * idx);
625 }
626
627 static struct prison_ip *
prison_ip_alloc(const pr_family_t af,uint32_t cnt,int flags)628 prison_ip_alloc(const pr_family_t af, uint32_t cnt, int flags)
629 {
630 struct prison_ip *pip;
631
632 pip = malloc(sizeof(struct prison_ip) + cnt * pr_families[af].size,
633 M_PRISON, flags);
634 if (pip != NULL)
635 pip->ips = cnt;
636 return (pip);
637 }
638
639 /*
640 * Allocate and copyin user supplied address list, sorting and validating.
641 * kern_jail_set() helper.
642 */
643 static struct prison_ip *
prison_ip_copyin(const pr_family_t af,void * op,uint32_t cnt)644 prison_ip_copyin(const pr_family_t af, void *op, uint32_t cnt)
645 {
646 prison_addr_cmp_t *const cmp = pr_families[af].cmp;
647 const size_t size = pr_families[af].size;
648 struct prison_ip *pip;
649
650 pip = prison_ip_alloc(af, cnt, M_WAITOK);
651 bcopy(op, pip->pr_ip, cnt * size);
652 /*
653 * IP addresses are all sorted but ip[0] to preserve
654 * the primary IP address as given from userland.
655 * This special IP is used for unbound outgoing
656 * connections as well for "loopback" traffic in case
657 * source address selection cannot find any more fitting
658 * address to connect from.
659 */
660 if (cnt > 1)
661 qsort(PR_IP(pip, af, 1), cnt - 1, size, cmp);
662 /*
663 * Check for duplicate addresses and do some simple
664 * zero and broadcast checks. If users give other bogus
665 * addresses it is their problem.
666 */
667 for (int i = 0; i < cnt; i++) {
668 if (!pr_families[af].valid(PR_IP(pip, af, i))) {
669 free(pip, M_PRISON);
670 return (NULL);
671 }
672 if (i + 1 < cnt &&
673 (cmp(PR_IP(pip, af, 0), PR_IP(pip, af, i + 1)) == 0 ||
674 cmp(PR_IP(pip, af, i), PR_IP(pip, af, i + 1)) == 0)) {
675 free(pip, M_PRISON);
676 return (NULL);
677 }
678 }
679
680 return (pip);
681 }
682
683 /*
684 * Allocate and dup parent prison address list.
685 * kern_jail_set() helper.
686 */
687 static void
prison_ip_dup(struct prison * ppr,struct prison * pr,const pr_family_t af)688 prison_ip_dup(struct prison *ppr, struct prison *pr, const pr_family_t af)
689 {
690 const struct prison_ip *ppip = ppr->pr_addrs[af];
691 struct prison_ip *pip;
692
693 if (ppip != NULL) {
694 pip = prison_ip_alloc(af, ppip->ips, M_WAITOK);
695 bcopy(ppip->pr_ip, pip->pr_ip, pip->ips * pr_families[af].size);
696 pr->pr_addrs[af] = pip;
697 }
698 }
699
700 /*
701 * Make sure the new set of IP addresses is a subset of the parent's list.
702 * Don't worry about the parent being unlocked, as any setting is done with
703 * allprison_lock held.
704 * kern_jail_set() helper.
705 */
706 static bool
prison_ip_parent_match(struct prison_ip * ppip,struct prison_ip * pip,const pr_family_t af)707 prison_ip_parent_match(struct prison_ip *ppip, struct prison_ip *pip,
708 const pr_family_t af)
709 {
710 prison_addr_cmp_t *const cmp = pr_families[af].cmp;
711 int i, j;
712
713 if (ppip == NULL)
714 return (false);
715
716 for (i = 0; i < ppip->ips; i++)
717 if (cmp(PR_IP(pip, af, 0), PR_IP(ppip, af, i)) == 0)
718 break;
719
720 if (i == ppip->ips)
721 /* Main address not present in parent. */
722 return (false);
723
724 if (pip->ips > 1) {
725 for (i = j = 1; i < pip->ips; i++) {
726 if (cmp(PR_IP(pip, af, i), PR_IP(ppip, af, 0)) == 0)
727 /* Equals to parent primary address. */
728 continue;
729 for (; j < ppip->ips; j++)
730 if (cmp(PR_IP(pip, af, i),
731 PR_IP(ppip, af, j)) == 0)
732 break;
733 if (j == ppip->ips)
734 break;
735 }
736 if (j == ppip->ips)
737 /* Address not present in parent. */
738 return (false);
739 }
740 return (true);
741 }
742
743 /*
744 * Check for conflicting IP addresses. We permit them if there is no more
745 * than one IP on each jail. If there is a duplicate on a jail with more
746 * than one IP stop checking and return error.
747 * kern_jail_set() helper.
748 */
749 static bool
prison_ip_conflict_check(const struct prison * ppr,const struct prison * pr,struct prison_ip * pip,pr_family_t af)750 prison_ip_conflict_check(const struct prison *ppr, const struct prison *pr,
751 struct prison_ip *pip, pr_family_t af)
752 {
753 const struct prison *tppr, *tpr;
754 int descend;
755
756 #ifdef VIMAGE
757 for (tppr = ppr; tppr != &prison0; tppr = tppr->pr_parent)
758 if (tppr->pr_flags & PR_VNET)
759 break;
760 #else
761 tppr = &prison0;
762 #endif
763 FOREACH_PRISON_DESCENDANT(tppr, tpr, descend) {
764 if (tpr == pr ||
765 #ifdef VIMAGE
766 (tpr != tppr && (tpr->pr_flags & PR_VNET)) ||
767 #endif
768 !prison_isalive(tpr)) {
769 descend = 0;
770 continue;
771 }
772 if (!(tpr->pr_flags & pr_families[af].ip_flag))
773 continue;
774 descend = 0;
775 if (tpr->pr_addrs[af] == NULL ||
776 (pip->ips == 1 && tpr->pr_addrs[af]->ips == 1))
777 continue;
778 for (int i = 0; i < pip->ips; i++)
779 if (prison_ip_check(tpr, af, PR_IP(pip, af, i)) == 0)
780 return (false);
781 }
782
783 return (true);
784 }
785
786 _Static_assert(offsetof(struct prison_ip, ctx) == 0,
787 "prison must start with epoch context");
788 static void
prison_ip_free_deferred(epoch_context_t ctx)789 prison_ip_free_deferred(epoch_context_t ctx)
790 {
791
792 free(ctx, M_PRISON);
793 }
794
795 static void
prison_ip_free(struct prison_ip * pip)796 prison_ip_free(struct prison_ip *pip)
797 {
798
799 if (pip != NULL)
800 NET_EPOCH_CALL(prison_ip_free_deferred, &pip->ctx);
801 }
802
803 static void
prison_ip_set(struct prison * pr,const pr_family_t af,struct prison_ip * new)804 prison_ip_set(struct prison *pr, const pr_family_t af, struct prison_ip *new)
805 {
806 struct prison_ip **mem, *old;
807
808 mtx_assert(&pr->pr_mtx, MA_OWNED);
809
810 mem = &pr->pr_addrs[af];
811
812 old = *mem;
813 atomic_store_ptr(mem, new);
814 prison_ip_free(old);
815 }
816
817 /*
818 * Restrict a prison's IP address list with its parent's, possibly replacing
819 * it. Return true if succeed, otherwise should redo.
820 * kern_jail_set() helper.
821 */
822 static bool
prison_ip_restrict(struct prison * pr,const pr_family_t af,struct prison_ip ** newp)823 prison_ip_restrict(struct prison *pr, const pr_family_t af,
824 struct prison_ip **newp)
825 {
826 struct prison_ip *ppip = pr->pr_parent->pr_addrs[af];
827 struct prison_ip *pip = pr->pr_addrs[af];
828 int (*const cmp)(const void *, const void *) = pr_families[af].cmp;
829 const size_t size = pr_families[af].size;
830 struct prison_ip *new = newp != NULL ? *newp : NULL;
831 uint32_t ips;
832
833 mtx_assert(&pr->pr_mtx, MA_OWNED);
834
835 /*
836 * Due to epoch-synchronized access to the IP address lists we always
837 * allocate a new list even if the old one has enough space. We could
838 * atomically update an IPv4 address inside a list, but that would
839 * screw up sorting, and in case of IPv6 we can't even atomically write
840 * one.
841 */
842 if (ppip == NULL) {
843 if (pip != NULL)
844 prison_ip_set(pr, af, NULL);
845 return (true);
846 }
847
848 if (!(pr->pr_flags & pr_families[af].ip_flag)) {
849 if (new == NULL) {
850 new = prison_ip_alloc(af, ppip->ips, M_NOWAIT);
851 if (new == NULL)
852 return (false); /* Redo */
853 }
854 /* This has no user settings, so just copy the parent's list. */
855 MPASS(new->ips == ppip->ips);
856 bcopy(ppip->pr_ip, new->pr_ip, ppip->ips * size);
857 prison_ip_set(pr, af, new);
858 if (newp != NULL)
859 *newp = NULL; /* Used */
860 } else if (pip != NULL) {
861 /* Remove addresses that aren't in the parent. */
862 int i;
863
864 i = 0; /* index in pip */
865 ips = 0; /* index in new */
866
867 if (new == NULL) {
868 new = prison_ip_alloc(af, pip->ips, M_NOWAIT);
869 if (new == NULL)
870 return (false); /* Redo */
871 }
872
873 for (int pi = 0; pi < ppip->ips; pi++)
874 if (cmp(PR_IP(pip, af, 0), PR_IP(ppip, af, pi)) == 0) {
875 /* Found our primary address in parent. */
876 bcopy(PR_IP(pip, af, i), PR_IP(new, af, ips),
877 size);
878 i++;
879 ips++;
880 break;
881 }
882 for (int pi = 1; i < pip->ips; ) {
883 /* Check against primary, which is unsorted. */
884 if (cmp(PR_IP(pip, af, i), PR_IP(ppip, af, 0)) == 0) {
885 /* Matches parent's primary address. */
886 bcopy(PR_IP(pip, af, i), PR_IP(new, af, ips),
887 size);
888 i++;
889 ips++;
890 continue;
891 }
892 /* The rest are sorted. */
893 switch (pi >= ppip->ips ? -1 :
894 cmp(PR_IP(pip, af, i), PR_IP(ppip, af, pi))) {
895 case -1:
896 i++;
897 break;
898 case 0:
899 bcopy(PR_IP(pip, af, i), PR_IP(new, af, ips),
900 size);
901 i++;
902 pi++;
903 ips++;
904 break;
905 case 1:
906 pi++;
907 break;
908 }
909 }
910 if (ips == 0) {
911 if (newp == NULL || *newp == NULL)
912 prison_ip_free(new);
913 new = NULL;
914 } else {
915 /* Shrink to real size */
916 KASSERT((new->ips >= ips),
917 ("Out-of-bounds write to prison_ip %p", new));
918 new->ips = ips;
919 }
920 prison_ip_set(pr, af, new);
921 if (newp != NULL)
922 *newp = NULL; /* Used */
923 }
924 return (true);
925 }
926
927 /*
928 * Fast-path check if an address belongs to a prison.
929 */
930 int
prison_ip_check(const struct prison * pr,const pr_family_t af,const void * addr)931 prison_ip_check(const struct prison *pr, const pr_family_t af,
932 const void *addr)
933 {
934 int (*const cmp)(const void *, const void *) = pr_families[af].cmp;
935 struct prison_ip *pip;
936 int i, a, z, d;
937
938 MPASS(mtx_owned(&pr->pr_mtx) ||
939 in_epoch(net_epoch_preempt) ||
940 sx_xlocked(&allprison_lock));
941
942 pip = atomic_load_ptr(&pr->pr_addrs[af]);
943 if (__predict_false(pip == NULL))
944 return (EAFNOSUPPORT);
945
946 /* Check the primary IP. */
947 if (cmp(PR_IP(pip, af, 0), addr) == 0)
948 return (0);
949
950 /*
951 * All the other IPs are sorted so we can do a binary search.
952 */
953 a = 0;
954 z = pip->ips - 2;
955 while (a <= z) {
956 i = (a + z) / 2;
957 d = cmp(PR_IP(pip, af, i + 1), addr);
958 if (d > 0)
959 z = i - 1;
960 else if (d < 0)
961 a = i + 1;
962 else
963 return (0);
964 }
965
966 return (EADDRNOTAVAIL);
967 }
968
969 /*
970 * Grab primary IP. Historically required mutex, but nothing prevents
971 * us to support epoch-protected access. Is it used in fast path?
972 * in{6}_jail.c helper
973 */
974 const void *
prison_ip_get0(const struct prison * pr,const pr_family_t af)975 prison_ip_get0(const struct prison *pr, const pr_family_t af)
976 {
977 const struct prison_ip *pip = pr->pr_addrs[af];
978
979 mtx_assert(&pr->pr_mtx, MA_OWNED);
980 MPASS(pip);
981
982 return (pip->pr_ip);
983 }
984
985 u_int
prison_ip_cnt(const struct prison * pr,const pr_family_t af)986 prison_ip_cnt(const struct prison *pr, const pr_family_t af)
987 {
988
989 return (pr->pr_addrs[af]->ips);
990 }
991 #endif /* defined(INET) || defined(INET6) */
992
993 int
kern_jail_set(struct thread * td,struct uio * optuio,int flags)994 kern_jail_set(struct thread *td, struct uio *optuio, int flags)
995 {
996 struct file *jfp_out;
997 struct nameidata nd;
998 #ifdef INET
999 struct prison_ip *ip4;
1000 #endif
1001 #ifdef INET6
1002 struct prison_ip *ip6;
1003 #endif
1004 struct vfsopt *opt;
1005 struct vfsoptlist *opts;
1006 struct prison *pr, *deadpr, *dinspr, *inspr, *mypr, *ppr, *tpr;
1007 struct ucred *jdcred;
1008 struct vnode *root;
1009 char *domain, *errmsg, *host, *name, *namelc, *p, *path, *uuid;
1010 char *g_path, *osrelstr;
1011 struct bool_flags *bf;
1012 struct jailsys_flags *jsf;
1013 #if defined(INET) || defined(INET6)
1014 void *op;
1015 #endif
1016 unsigned long hid;
1017 size_t namelen, onamelen, pnamelen;
1018 int created, cuflags, descend, drflags, enforce;
1019 int error, errmsg_len, errmsg_pos;
1020 int gotchildmax, gotenforce, gothid, gotrsnum, gotslevel;
1021 int deadid, jfd_in, jfd_out, jfd_pos, jid, jsys, len, level;
1022 int childmax, osreldt, rsnum, slevel;
1023 #ifdef INET
1024 int ip4s;
1025 bool redo_ip4;
1026 #endif
1027 #ifdef INET6
1028 int ip6s;
1029 bool redo_ip6;
1030 #endif
1031 bool maybe_changed;
1032 uint64_t pr_allow, ch_allow, pr_flags, ch_flags;
1033 uint64_t pr_allow_diff;
1034 unsigned tallow;
1035 char numbuf[12];
1036
1037 mypr = td->td_ucred->cr_prison;
1038 if (((flags & (JAIL_CREATE | JAIL_AT_DESC)) == JAIL_CREATE) &&
1039 mypr->pr_childmax == 0)
1040 return (EPERM);
1041 if (flags & ~JAIL_SET_MASK)
1042 return (EINVAL);
1043 if ((flags & (JAIL_USE_DESC | JAIL_AT_DESC)) ==
1044 (JAIL_USE_DESC | JAIL_AT_DESC))
1045 return (EINVAL);
1046 prison_hold(mypr);
1047
1048 #ifdef INET
1049 ip4 = NULL;
1050 #endif
1051 #ifdef INET6
1052 ip6 = NULL;
1053 #endif
1054 g_path = NULL;
1055 jfp_out = NULL;
1056 jfd_out = -1;
1057 /*
1058 * Check all the parameters before committing to anything. Not all
1059 * errors can be caught early, but we may as well try. Also, this
1060 * takes care of some expensive stuff (path lookup) before getting
1061 * the allprison lock.
1062 *
1063 * XXX Jails are not filesystems, and jail parameters are not mount
1064 * options. But it makes more sense to re-use the vfsopt code
1065 * than duplicate it under a different name.
1066 */
1067 error = vfs_buildopts(optuio, &opts);
1068 if (error) {
1069 opts = NULL;
1070 goto done_free;
1071 }
1072
1073 cuflags = flags & (JAIL_CREATE | JAIL_UPDATE);
1074 if (!cuflags) {
1075 error = EINVAL;
1076 vfs_opterror(opts, "no valid operation (create or update)");
1077 goto done_errmsg;
1078 }
1079
1080 error = vfs_copyopt(opts, "desc", &jfd_in, sizeof(jfd_in));
1081 if (error == ENOENT) {
1082 if (flags & (JAIL_USE_DESC | JAIL_AT_DESC | JAIL_GET_DESC |
1083 JAIL_OWN_DESC)) {
1084 vfs_opterror(opts, "missing desc");
1085 goto done_errmsg;
1086 }
1087 jfd_in = -1;
1088 } else if (error != 0)
1089 goto done_free;
1090 else {
1091 if (!(flags & (JAIL_USE_DESC | JAIL_AT_DESC | JAIL_GET_DESC |
1092 JAIL_OWN_DESC))) {
1093 error = EINVAL;
1094 vfs_opterror(opts, "unexpected desc");
1095 goto done_errmsg;
1096 }
1097 if (flags & JAIL_AT_DESC) {
1098 /*
1099 * Look up and create jails based on the
1100 * descriptor's prison.
1101 */
1102 prison_free(mypr);
1103 error = jaildesc_find(td, jfd_in, &mypr, NULL);
1104 if (error != 0) {
1105 vfs_opterror(opts, error == ENOENT ?
1106 "descriptor to dead jail" :
1107 "not a jail descriptor");
1108 goto done_errmsg;
1109 }
1110 if ((flags & JAIL_CREATE) && mypr->pr_childmax == 0) {
1111 error = EPERM;
1112 goto done_free;
1113 }
1114 }
1115 if (flags & (JAIL_GET_DESC | JAIL_OWN_DESC)) {
1116 /* Allocate a jail descriptor to return later. */
1117 error = jaildesc_alloc(td, &jfp_out, &jfd_out,
1118 flags & JAIL_OWN_DESC);
1119 if (error)
1120 goto done_free;
1121 }
1122 }
1123
1124 /*
1125 * Delay the permission check if using a jail descriptor,
1126 * until we get the descriptor's credentials.
1127 */
1128 if (!(flags & JAIL_USE_DESC)) {
1129 error = priv_check(td, PRIV_JAIL_SET);
1130 if (error == 0 && (flags & JAIL_ATTACH))
1131 error = priv_check(td, PRIV_JAIL_ATTACH);
1132 if (error)
1133 goto done_free;
1134 }
1135
1136 error = vfs_copyopt(opts, "jid", &jid, sizeof(jid));
1137 if (error == ENOENT)
1138 jid = 0;
1139 else if (error != 0)
1140 goto done_free;
1141
1142 error = vfs_copyopt(opts, "securelevel", &slevel, sizeof(slevel));
1143 if (error == ENOENT)
1144 gotslevel = 0;
1145 else if (error != 0)
1146 goto done_free;
1147 else
1148 gotslevel = 1;
1149
1150 error =
1151 vfs_copyopt(opts, "children.max", &childmax, sizeof(childmax));
1152 if (error == ENOENT)
1153 gotchildmax = 0;
1154 else if (error != 0)
1155 goto done_free;
1156 else
1157 gotchildmax = 1;
1158
1159 error = vfs_copyopt(opts, "enforce_statfs", &enforce, sizeof(enforce));
1160 if (error == ENOENT)
1161 gotenforce = 0;
1162 else if (error != 0)
1163 goto done_free;
1164 else if (enforce < 0 || enforce > 2) {
1165 error = EINVAL;
1166 goto done_free;
1167 } else
1168 gotenforce = 1;
1169
1170 error = vfs_copyopt(opts, "devfs_ruleset", &rsnum, sizeof(rsnum));
1171 if (error == ENOENT)
1172 gotrsnum = 0;
1173 else if (error != 0)
1174 goto done_free;
1175 else
1176 gotrsnum = 1;
1177
1178 pr_flags = ch_flags = 0;
1179 for (bf = pr_flag_bool;
1180 bf < pr_flag_bool + nitems(pr_flag_bool);
1181 bf++) {
1182 vfs_flagopt(opts, bf->name, &pr_flags, bf->flag);
1183 vfs_flagopt(opts, bf->noname, &ch_flags, bf->flag);
1184 }
1185 ch_flags |= pr_flags;
1186 for (jsf = pr_flag_jailsys;
1187 jsf < pr_flag_jailsys + nitems(pr_flag_jailsys);
1188 jsf++) {
1189 error = vfs_copyopt(opts, jsf->name, &jsys, sizeof(jsys));
1190 if (error == ENOENT)
1191 continue;
1192 if (error != 0)
1193 goto done_free;
1194 switch (jsys) {
1195 case JAIL_SYS_DISABLE:
1196 if (!jsf->disable) {
1197 error = EINVAL;
1198 goto done_free;
1199 }
1200 pr_flags |= jsf->disable;
1201 break;
1202 case JAIL_SYS_NEW:
1203 pr_flags |= jsf->new;
1204 break;
1205 case JAIL_SYS_INHERIT:
1206 break;
1207 default:
1208 error = EINVAL;
1209 goto done_free;
1210 }
1211 ch_flags |= jsf->new | jsf->disable;
1212 }
1213 if ((flags & (JAIL_CREATE | JAIL_ATTACH)) == JAIL_CREATE
1214 && !(pr_flags & PR_PERSIST)) {
1215 error = EINVAL;
1216 vfs_opterror(opts, "new jail must persist or attach");
1217 goto done_errmsg;
1218 }
1219 #ifdef VIMAGE
1220 if ((flags & JAIL_UPDATE) && (ch_flags & PR_VNET)) {
1221 error = EINVAL;
1222 vfs_opterror(opts, "vnet cannot be changed after creation");
1223 goto done_errmsg;
1224 }
1225 #endif
1226 #ifdef INET
1227 if ((flags & JAIL_UPDATE) && (ch_flags & PR_IP4_USER)) {
1228 error = EINVAL;
1229 vfs_opterror(opts, "ip4 cannot be changed after creation");
1230 goto done_errmsg;
1231 }
1232 #endif
1233 #ifdef INET6
1234 if ((flags & JAIL_UPDATE) && (ch_flags & PR_IP6_USER)) {
1235 error = EINVAL;
1236 vfs_opterror(opts, "ip6 cannot be changed after creation");
1237 goto done_errmsg;
1238 }
1239 #endif
1240
1241 pr_allow = ch_allow = 0;
1242 for (bf = pr_flag_allow;
1243 bf < pr_flag_allow + nitems(pr_flag_allow) &&
1244 atomic_load_int(&bf->flag) != 0;
1245 bf++) {
1246 vfs_flagopt(opts, bf->name, &pr_allow, bf->flag);
1247 vfs_flagopt(opts, bf->noname, &ch_allow, bf->flag);
1248 }
1249 ch_allow |= pr_allow;
1250
1251 error = vfs_getopt(opts, "name", (void **)&name, &len);
1252 if (error == ENOENT)
1253 name = NULL;
1254 else if (error != 0)
1255 goto done_free;
1256 else {
1257 if (len == 0 || name[len - 1] != '\0') {
1258 error = EINVAL;
1259 goto done_free;
1260 }
1261 if (len > MAXHOSTNAMELEN) {
1262 error = ENAMETOOLONG;
1263 goto done_free;
1264 }
1265 }
1266
1267 error = vfs_getopt(opts, "host.hostname", (void **)&host, &len);
1268 if (error == ENOENT)
1269 host = NULL;
1270 else if (error != 0)
1271 goto done_free;
1272 else {
1273 ch_flags |= PR_HOST;
1274 pr_flags |= PR_HOST;
1275 if (len == 0 || host[len - 1] != '\0') {
1276 error = EINVAL;
1277 goto done_free;
1278 }
1279 if (len > MAXHOSTNAMELEN) {
1280 error = ENAMETOOLONG;
1281 goto done_free;
1282 }
1283 }
1284
1285 error = vfs_getopt(opts, "host.domainname", (void **)&domain, &len);
1286 if (error == ENOENT)
1287 domain = NULL;
1288 else if (error != 0)
1289 goto done_free;
1290 else {
1291 ch_flags |= PR_HOST;
1292 pr_flags |= PR_HOST;
1293 if (len == 0 || domain[len - 1] != '\0') {
1294 error = EINVAL;
1295 goto done_free;
1296 }
1297 if (len > MAXHOSTNAMELEN) {
1298 error = ENAMETOOLONG;
1299 goto done_free;
1300 }
1301 }
1302
1303 error = vfs_getopt(opts, "host.hostuuid", (void **)&uuid, &len);
1304 if (error == ENOENT)
1305 uuid = NULL;
1306 else if (error != 0)
1307 goto done_free;
1308 else {
1309 ch_flags |= PR_HOST;
1310 pr_flags |= PR_HOST;
1311 if (len == 0 || uuid[len - 1] != '\0') {
1312 error = EINVAL;
1313 goto done_free;
1314 }
1315 if (len > HOSTUUIDLEN) {
1316 error = ENAMETOOLONG;
1317 goto done_free;
1318 }
1319 }
1320
1321 #ifdef COMPAT_FREEBSD32
1322 if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
1323 uint32_t hid32;
1324
1325 error = vfs_copyopt(opts, "host.hostid", &hid32, sizeof(hid32));
1326 hid = hid32;
1327 } else
1328 #endif
1329 error = vfs_copyopt(opts, "host.hostid", &hid, sizeof(hid));
1330 if (error == ENOENT)
1331 gothid = 0;
1332 else if (error != 0)
1333 goto done_free;
1334 else {
1335 gothid = 1;
1336 ch_flags |= PR_HOST;
1337 pr_flags |= PR_HOST;
1338 }
1339
1340 #ifdef INET
1341 error = vfs_getopt(opts, "ip4.addr", &op, &ip4s);
1342 if (error == ENOENT)
1343 ip4s = 0;
1344 else if (error != 0)
1345 goto done_free;
1346 else if (ip4s & (sizeof(struct in_addr) - 1)) {
1347 error = EINVAL;
1348 goto done_free;
1349 } else {
1350 ch_flags |= PR_IP4_USER;
1351 pr_flags |= PR_IP4_USER;
1352 if (ip4s > 0) {
1353 ip4s /= sizeof(struct in_addr);
1354 if (ip4s > jail_max_af_ips) {
1355 error = EINVAL;
1356 vfs_opterror(opts, "too many IPv4 addresses");
1357 goto done_errmsg;
1358 }
1359 ip4 = prison_ip_copyin(PR_INET, op, ip4s);
1360 if (ip4 == NULL) {
1361 error = EINVAL;
1362 goto done_free;
1363 }
1364 }
1365 }
1366 #endif
1367
1368 #ifdef INET6
1369 error = vfs_getopt(opts, "ip6.addr", &op, &ip6s);
1370 if (error == ENOENT)
1371 ip6s = 0;
1372 else if (error != 0)
1373 goto done_free;
1374 else if (ip6s & (sizeof(struct in6_addr) - 1)) {
1375 error = EINVAL;
1376 goto done_free;
1377 } else {
1378 ch_flags |= PR_IP6_USER;
1379 pr_flags |= PR_IP6_USER;
1380 if (ip6s > 0) {
1381 ip6s /= sizeof(struct in6_addr);
1382 if (ip6s > jail_max_af_ips) {
1383 error = EINVAL;
1384 vfs_opterror(opts, "too many IPv6 addresses");
1385 goto done_errmsg;
1386 }
1387 ip6 = prison_ip_copyin(PR_INET6, op, ip6s);
1388 if (ip6 == NULL) {
1389 error = EINVAL;
1390 goto done_free;
1391 }
1392 }
1393 }
1394 #endif
1395
1396 #if defined(VIMAGE) && (defined(INET) || defined(INET6))
1397 if ((ch_flags & PR_VNET) && (ch_flags & (PR_IP4_USER | PR_IP6_USER))) {
1398 error = EINVAL;
1399 vfs_opterror(opts,
1400 "vnet jails cannot have IP address restrictions");
1401 goto done_errmsg;
1402 }
1403 #endif
1404
1405 error = vfs_getopt(opts, "osrelease", (void **)&osrelstr, &len);
1406 if (error == ENOENT)
1407 osrelstr = NULL;
1408 else if (error != 0)
1409 goto done_free;
1410 else {
1411 if (flags & JAIL_UPDATE) {
1412 error = EINVAL;
1413 vfs_opterror(opts,
1414 "osrelease cannot be changed after creation");
1415 goto done_errmsg;
1416 }
1417 if (len == 0 || osrelstr[len - 1] != '\0') {
1418 error = EINVAL;
1419 goto done_free;
1420 }
1421 if (len >= OSRELEASELEN) {
1422 error = ENAMETOOLONG;
1423 vfs_opterror(opts,
1424 "osrelease string must be 1-%d bytes long",
1425 OSRELEASELEN - 1);
1426 goto done_errmsg;
1427 }
1428 }
1429
1430 error = vfs_copyopt(opts, "osreldate", &osreldt, sizeof(osreldt));
1431 if (error == ENOENT)
1432 osreldt = 0;
1433 else if (error != 0)
1434 goto done_free;
1435 else {
1436 if (flags & JAIL_UPDATE) {
1437 error = EINVAL;
1438 vfs_opterror(opts,
1439 "osreldate cannot be changed after creation");
1440 goto done_errmsg;
1441 }
1442 if (osreldt == 0) {
1443 error = EINVAL;
1444 vfs_opterror(opts, "osreldate cannot be 0");
1445 goto done_errmsg;
1446 }
1447 }
1448
1449 root = NULL;
1450 error = vfs_getopt(opts, "path", (void **)&path, &len);
1451 if (error == ENOENT)
1452 path = NULL;
1453 else if (error != 0)
1454 goto done_free;
1455 else {
1456 if (flags & JAIL_UPDATE) {
1457 error = EINVAL;
1458 vfs_opterror(opts,
1459 "path cannot be changed after creation");
1460 goto done_errmsg;
1461 }
1462 if (len == 0 || path[len - 1] != '\0') {
1463 error = EINVAL;
1464 goto done_free;
1465 }
1466 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, path);
1467 error = namei(&nd);
1468 if (error)
1469 goto done_free;
1470 root = nd.ni_vp;
1471 NDFREE_PNBUF(&nd);
1472 g_path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1473 strlcpy(g_path, path, MAXPATHLEN);
1474 error = vn_path_to_global_path(td, root, g_path, MAXPATHLEN);
1475 if (error == 0) {
1476 path = g_path;
1477 } else {
1478 /* exit on other errors */
1479 goto done_free;
1480 }
1481 if (root->v_type != VDIR) {
1482 error = ENOTDIR;
1483 vput(root);
1484 goto done_free;
1485 }
1486 VOP_UNLOCK(root);
1487 }
1488
1489 /*
1490 * Find the specified jail, or at least its parent.
1491 * This abuses the file error codes ENOENT and EEXIST.
1492 */
1493 pr = NULL;
1494 inspr = NULL;
1495 deadpr = NULL;
1496 maybe_changed = false;
1497 if (cuflags == JAIL_CREATE && jid == 0 && name != NULL) {
1498 namelc = strrchr(name, '.');
1499 jid = strtoul(namelc != NULL ? namelc + 1 : name, &p, 10);
1500 if (*p != '\0')
1501 jid = 0;
1502 }
1503 sx_xlock(&allprison_lock);
1504 drflags = PD_LIST_XLOCKED;
1505 ppr = mypr;
1506 if (!prison_isalive(ppr)) {
1507 /* This jail is dying. This process will surely follow. */
1508 error = EAGAIN;
1509 goto done_deref;
1510 }
1511 if (flags & JAIL_USE_DESC) {
1512 /* Get the jail from its descriptor. */
1513 error = jaildesc_find(td, jfd_in, &pr, &jdcred);
1514 if (error) {
1515 vfs_opterror(opts, error == ENOENT ?
1516 "descriptor to dead jail" :
1517 "not a jail descriptor");
1518 goto done_deref;
1519 }
1520 drflags |= PD_DEREF;
1521 error = priv_check_cred(jdcred, PRIV_JAIL_SET);
1522 if (error == 0 && (flags & JAIL_ATTACH))
1523 error = priv_check_cred(jdcred, PRIV_JAIL_ATTACH);
1524 crfree(jdcred);
1525 if (error)
1526 goto done_deref;
1527 mtx_lock(&pr->pr_mtx);
1528 drflags |= PD_LOCKED;
1529 if (cuflags == JAIL_CREATE) {
1530 error = EEXIST;
1531 vfs_opterror(opts, "jail %d already exists",
1532 pr->pr_id);
1533 goto done_deref;
1534 }
1535 if (!prison_isalive(pr)) {
1536 /* While a jid can be resurrected, the prison
1537 * itself cannot.
1538 */
1539 error = ENOENT;
1540 vfs_opterror(opts, "jail %d is dying", pr->pr_id);
1541 goto done_deref;
1542 }
1543 if (jid != 0 && jid != pr->pr_id) {
1544 error = EINVAL;
1545 vfs_opterror(opts, "cannot change jid");
1546 goto done_deref;
1547 }
1548 jid = pr->pr_id;
1549 } else if (jid != 0) {
1550 if (jid < 0) {
1551 error = EINVAL;
1552 vfs_opterror(opts, "negative jid");
1553 goto done_deref;
1554 }
1555 /*
1556 * See if a requested jid already exists. Keep track of
1557 * where it can be inserted later.
1558 */
1559 TAILQ_FOREACH(inspr, &allprison, pr_list) {
1560 if (inspr->pr_id < jid)
1561 continue;
1562 if (inspr->pr_id > jid)
1563 break;
1564 if (prison_isalive(inspr)) {
1565 pr = inspr;
1566 mtx_lock(&pr->pr_mtx);
1567 drflags |= PD_LOCKED;
1568 } else {
1569 /* Note a dying jail to handle later. */
1570 deadpr = inspr;
1571 }
1572 inspr = NULL;
1573 break;
1574 }
1575 if (cuflags == JAIL_CREATE && pr != NULL) {
1576 /*
1577 * Even creators that cannot see the jail will
1578 * get EEXIST.
1579 */
1580 error = EEXIST;
1581 vfs_opterror(opts, "jail %d already exists", jid);
1582 goto done_deref;
1583 }
1584 if ((pr == NULL)
1585 ? cuflags == JAIL_UPDATE
1586 : !prison_ischild(mypr, pr)) {
1587 /*
1588 * Updaters get ENOENT for nonexistent jails,
1589 * or for jails they cannot see. The latter
1590 * case is true even for CREATE | UPDATE,
1591 * which normally cannot give this error.
1592 */
1593 error = ENOENT;
1594 vfs_opterror(opts, "jail %d not found", jid);
1595 goto done_deref;
1596 }
1597 }
1598 /*
1599 * If the caller provided a name, look for a jail by that name.
1600 * This has different semantics for creates and updates keyed by jid
1601 * (where the name must not already exist in a different jail),
1602 * and updates keyed by the name itself (where the name must exist
1603 * because that is the jail being updated).
1604 */
1605 namelc = NULL;
1606 if (name != NULL) {
1607 namelc = strrchr(name, '.');
1608 if (namelc == NULL)
1609 namelc = name;
1610 else {
1611 /*
1612 * This is a hierarchical name. Split it into the
1613 * parent and child names, and make sure the parent
1614 * exists or matches an already found jail.
1615 */
1616 if (pr != NULL) {
1617 if (strncmp(name, ppr->pr_name, namelc - name)
1618 || ppr->pr_name[namelc - name] != '\0') {
1619 error = EINVAL;
1620 vfs_opterror(opts,
1621 "cannot change jail's parent");
1622 goto done_deref;
1623 }
1624 } else {
1625 *namelc = '\0';
1626 ppr = prison_find_name(mypr, name);
1627 if (ppr == NULL) {
1628 error = ENOENT;
1629 vfs_opterror(opts,
1630 "jail \"%s\" not found", name);
1631 goto done_deref;
1632 }
1633 mtx_unlock(&ppr->pr_mtx);
1634 if (!prison_isalive(ppr)) {
1635 error = ENOENT;
1636 vfs_opterror(opts,
1637 "jail \"%s\" is dying", name);
1638 goto done_deref;
1639 }
1640 *namelc = '.';
1641 }
1642 namelc++;
1643 }
1644 if (namelc[0] != '\0') {
1645 pnamelen =
1646 (ppr == &prison0) ? 0 : strlen(ppr->pr_name) + 1;
1647 FOREACH_PRISON_CHILD(ppr, tpr) {
1648 if (tpr == pr || !prison_isalive(tpr) ||
1649 strcmp(tpr->pr_name + pnamelen, namelc))
1650 continue;
1651 if (cuflags == JAIL_CREATE || pr != NULL) {
1652 /*
1653 * Create, or update(jid): name must
1654 * not exist in an active sibling jail.
1655 */
1656 error = EEXIST;
1657 vfs_opterror(opts,
1658 "jail \"%s\" already exists", name);
1659 goto done_deref;
1660 }
1661 /* Use this jail for updates. */
1662 pr = tpr;
1663 mtx_lock(&pr->pr_mtx);
1664 drflags |= PD_LOCKED;
1665 break;
1666 }
1667 /*
1668 * Update: name must exist if no jid is specified.
1669 * As with the jid case, the jail must be currently
1670 * visible, or else even CREATE | UPDATE will get
1671 * an error.
1672 */
1673 if ((pr == NULL)
1674 ? cuflags == JAIL_UPDATE
1675 : !prison_isalive(pr)) {
1676 error = ENOENT;
1677 vfs_opterror(opts, "jail \"%s\" not found",
1678 name);
1679 goto done_deref;
1680 }
1681 }
1682 }
1683 /* Update: must provide a desc, jid, or name. */
1684 else if (cuflags == JAIL_UPDATE && pr == NULL) {
1685 error = ENOENT;
1686 vfs_opterror(opts, "update specified no jail");
1687 goto done_deref;
1688 }
1689
1690 /* If there's no prison to update, create a new one and link it in. */
1691 created = pr == NULL;
1692 if (created) {
1693 for (tpr = mypr; tpr != NULL; tpr = tpr->pr_parent)
1694 if (tpr->pr_childcount >= tpr->pr_childmax) {
1695 error = EPERM;
1696 vfs_opterror(opts, "prison limit exceeded");
1697 goto done_deref;
1698 }
1699
1700 if (deadpr != NULL) {
1701 /*
1702 * The prison being created has the same ID as a dying
1703 * one. Handle this by giving the dying jail a new ID.
1704 * This may cause some confusion to user space, but
1705 * only to those listing dying jails.
1706 */
1707 deadid = get_next_deadid(&dinspr);
1708 if (deadid == 0) {
1709 error = EAGAIN;
1710 vfs_opterror(opts, "no available jail IDs");
1711 goto done_deref;
1712 }
1713 mtx_lock(&deadpr->pr_mtx);
1714 deadpr->pr_id = deadid;
1715 mtx_unlock(&deadpr->pr_mtx);
1716 if (dinspr == deadpr)
1717 inspr = deadpr;
1718 else {
1719 inspr = TAILQ_NEXT(deadpr, pr_list);
1720 TAILQ_REMOVE(&allprison, deadpr, pr_list);
1721 if (dinspr != NULL)
1722 TAILQ_INSERT_AFTER(&allprison, dinspr,
1723 deadpr, pr_list);
1724 else
1725 TAILQ_INSERT_HEAD(&allprison, deadpr,
1726 pr_list);
1727 }
1728 }
1729 if (jid == 0 && (jid = get_next_prid(&inspr)) == 0) {
1730 error = EAGAIN;
1731 vfs_opterror(opts, "no available jail IDs");
1732 goto done_deref;
1733 }
1734
1735 pr = malloc(sizeof(*pr), M_PRISON, M_WAITOK | M_ZERO);
1736 pr->pr_state = PRISON_STATE_INVALID;
1737 refcount_init(&pr->pr_ref, 1);
1738 refcount_init(&pr->pr_uref, 0);
1739 drflags |= PD_DEREF;
1740 LIST_INIT(&pr->pr_children);
1741 mtx_init(&pr->pr_mtx, "jail mutex", NULL, MTX_DEF | MTX_DUPOK);
1742 TASK_INIT(&pr->pr_task, 0, prison_complete, pr);
1743
1744 pr->pr_id = jid;
1745 if (inspr != NULL)
1746 TAILQ_INSERT_BEFORE(inspr, pr, pr_list);
1747 else
1748 TAILQ_INSERT_TAIL(&allprison, pr, pr_list);
1749
1750 pr->pr_parent = ppr;
1751 prison_hold(ppr);
1752 prison_proc_hold(ppr);
1753 LIST_INSERT_HEAD(&ppr->pr_children, pr, pr_sibling);
1754 for (tpr = ppr; tpr != NULL; tpr = tpr->pr_parent)
1755 tpr->pr_childcount++;
1756 pr->pr_klist = knlist_alloc(&pr->pr_mtx);
1757
1758 /* Set some default values, and inherit some from the parent. */
1759 if (namelc == NULL)
1760 namelc = "";
1761 if (path == NULL) {
1762 path = "/";
1763 root = mypr->pr_root;
1764 vref(root);
1765 }
1766 strlcpy(pr->pr_hostuuid, DEFAULT_HOSTUUID, HOSTUUIDLEN);
1767 pr->pr_flags |= PR_HOST;
1768 #if defined(INET) || defined(INET6)
1769 #ifdef VIMAGE
1770 if (!(pr_flags & PR_VNET))
1771 #endif
1772 {
1773 #ifdef INET
1774 if (!(ch_flags & PR_IP4_USER))
1775 pr->pr_flags |= PR_IP4 | PR_IP4_USER;
1776 else if (!(pr_flags & PR_IP4_USER)) {
1777 pr->pr_flags |= ppr->pr_flags & PR_IP4;
1778 prison_ip_dup(ppr, pr, PR_INET);
1779 }
1780 #endif
1781 #ifdef INET6
1782 if (!(ch_flags & PR_IP6_USER))
1783 pr->pr_flags |= PR_IP6 | PR_IP6_USER;
1784 else if (!(pr_flags & PR_IP6_USER)) {
1785 pr->pr_flags |= ppr->pr_flags & PR_IP6;
1786 prison_ip_dup(ppr, pr, PR_INET6);
1787 }
1788 #endif
1789 }
1790 #endif
1791 /* Source address selection is always on by default. */
1792 pr->pr_flags |= _PR_IP_SADDRSEL;
1793
1794 pr->pr_securelevel = ppr->pr_securelevel;
1795 pr->pr_allow = JAIL_DEFAULT_ALLOW & ppr->pr_allow;
1796 pr->pr_enforce_statfs = jail_default_enforce_statfs;
1797 pr->pr_devfs_rsnum = ppr->pr_devfs_rsnum;
1798
1799 pr->pr_osreldate = osreldt ? osreldt : ppr->pr_osreldate;
1800 if (osrelstr == NULL)
1801 strlcpy(pr->pr_osrelease, ppr->pr_osrelease,
1802 sizeof(pr->pr_osrelease));
1803 else
1804 strlcpy(pr->pr_osrelease, osrelstr,
1805 sizeof(pr->pr_osrelease));
1806
1807 #ifdef VIMAGE
1808 /*
1809 * Allocate a new vnet if specified.
1810 *
1811 * Set PR_VNET now if so, so that the vnet is disposed of
1812 * properly when the jail is destroyed.
1813 */
1814 if (pr_flags & PR_VNET) {
1815 pr->pr_flags |= PR_VNET;
1816 pr->pr_vnet = vnet_alloc();
1817 } else {
1818 pr->pr_vnet = ppr->pr_vnet;
1819 }
1820 #endif
1821 /*
1822 * Allocate a dedicated cpuset for each jail.
1823 * Unlike other initial settings, this may return an error.
1824 */
1825 error = cpuset_create_root(ppr, &pr->pr_cpuset);
1826 if (error)
1827 goto done_deref;
1828
1829 mtx_lock(&pr->pr_mtx);
1830 drflags |= PD_LOCKED;
1831 } else {
1832 /*
1833 * Grab a reference for existing prisons, to ensure they
1834 * continue to exist for the duration of the call.
1835 */
1836 if (!(drflags & PD_DEREF)) {
1837 prison_hold(pr);
1838 drflags |= PD_DEREF;
1839 }
1840 #if defined(VIMAGE) && (defined(INET) || defined(INET6))
1841 if ((pr->pr_flags & PR_VNET) &&
1842 (ch_flags & (PR_IP4_USER | PR_IP6_USER))) {
1843 error = EINVAL;
1844 vfs_opterror(opts,
1845 "vnet jails cannot have IP address restrictions");
1846 goto done_deref;
1847 }
1848 #endif
1849 #ifdef INET
1850 if (PR_IP4_USER & ch_flags & (pr_flags ^ pr->pr_flags)) {
1851 error = EINVAL;
1852 vfs_opterror(opts,
1853 "ip4 cannot be changed after creation");
1854 goto done_deref;
1855 }
1856 #endif
1857 #ifdef INET6
1858 if (PR_IP6_USER & ch_flags & (pr_flags ^ pr->pr_flags)) {
1859 error = EINVAL;
1860 vfs_opterror(opts,
1861 "ip6 cannot be changed after creation");
1862 goto done_deref;
1863 }
1864 #endif
1865 }
1866
1867 /* Do final error checking before setting anything. */
1868 if (gotslevel) {
1869 if (slevel < ppr->pr_securelevel) {
1870 error = EPERM;
1871 goto done_deref;
1872 }
1873 }
1874 if (gotchildmax) {
1875 if (childmax >= ppr->pr_childmax) {
1876 error = EPERM;
1877 goto done_deref;
1878 }
1879 }
1880 if (gotenforce) {
1881 if (enforce < ppr->pr_enforce_statfs) {
1882 error = EPERM;
1883 goto done_deref;
1884 }
1885 }
1886 if (gotrsnum) {
1887 /*
1888 * devfs_rsnum is a uint16_t
1889 */
1890 if (rsnum < 0 || rsnum > 65535) {
1891 error = EINVAL;
1892 goto done_deref;
1893 }
1894 /*
1895 * Nested jails always inherit parent's devfs ruleset
1896 */
1897 if (jailed(td->td_ucred)) {
1898 if (rsnum > 0 && rsnum != ppr->pr_devfs_rsnum) {
1899 error = EPERM;
1900 goto done_deref;
1901 } else
1902 rsnum = ppr->pr_devfs_rsnum;
1903 }
1904 }
1905 #ifdef INET
1906 if (ip4s > 0) {
1907 if ((ppr->pr_flags & PR_IP4) &&
1908 !prison_ip_parent_match(ppr->pr_addrs[PR_INET], ip4,
1909 PR_INET)) {
1910 error = EPERM;
1911 goto done_deref;
1912 }
1913 if (!prison_ip_conflict_check(ppr, pr, ip4, PR_INET)) {
1914 error = EADDRINUSE;
1915 vfs_opterror(opts, "IPv4 addresses clash");
1916 goto done_deref;
1917 }
1918 }
1919 #endif
1920 #ifdef INET6
1921 if (ip6s > 0) {
1922 if ((ppr->pr_flags & PR_IP6) &&
1923 !prison_ip_parent_match(ppr->pr_addrs[PR_INET6], ip6,
1924 PR_INET6)) {
1925 error = EPERM;
1926 goto done_deref;
1927 }
1928 if (!prison_ip_conflict_check(ppr, pr, ip6, PR_INET6)) {
1929 error = EADDRINUSE;
1930 vfs_opterror(opts, "IPv6 addresses clash");
1931 goto done_deref;
1932 }
1933 }
1934 #endif
1935 onamelen = namelen = 0;
1936 if (namelc != NULL) {
1937 /* Give a default name of the jid. Also allow the name to be
1938 * explicitly the jid - but not any other number, and only in
1939 * normal form (no leading zero/etc).
1940 */
1941 if (namelc[0] == '\0')
1942 snprintf(namelc = numbuf, sizeof(numbuf), "%d", jid);
1943 else if ((strtoul(namelc, &p, 10) != jid ||
1944 namelc[0] < '1' || namelc[0] > '9') && *p == '\0') {
1945 error = EINVAL;
1946 vfs_opterror(opts,
1947 "name cannot be numeric (unless it is the jid)");
1948 goto done_deref;
1949 }
1950 /*
1951 * Make sure the name isn't too long for the prison or its
1952 * children.
1953 */
1954 pnamelen = (ppr == &prison0) ? 0 : strlen(ppr->pr_name) + 1;
1955 onamelen = strlen(pr->pr_name + pnamelen);
1956 namelen = strlen(namelc);
1957 if (pnamelen + namelen + 1 > sizeof(pr->pr_name)) {
1958 error = ENAMETOOLONG;
1959 goto done_deref;
1960 }
1961 FOREACH_PRISON_DESCENDANT(pr, tpr, descend) {
1962 if (strlen(tpr->pr_name) + (namelen - onamelen) >=
1963 sizeof(pr->pr_name)) {
1964 error = ENAMETOOLONG;
1965 goto done_deref;
1966 }
1967 }
1968 }
1969 pr_allow_diff = pr_allow & ~ppr->pr_allow;
1970 if (pr_allow_diff & ~PR_ALLOW_DIFFERENCES) {
1971 error = EPERM;
1972 goto done_deref;
1973 }
1974
1975 /*
1976 * Let modules check their parameters. This requires unlocking and
1977 * then re-locking the prison, but this is still a valid state as long
1978 * as allprison_lock remains xlocked.
1979 */
1980 mtx_unlock(&pr->pr_mtx);
1981 drflags &= ~PD_LOCKED;
1982 error = osd_jail_call(pr, PR_METHOD_CHECK, opts);
1983 if (error != 0)
1984 goto done_deref;
1985 mtx_lock(&pr->pr_mtx);
1986 drflags |= PD_LOCKED;
1987
1988 /* At this point, all valid parameters should have been noted. */
1989 TAILQ_FOREACH(opt, opts, link) {
1990 if (!opt->seen && strcmp(opt->name, "errmsg")) {
1991 error = EINVAL;
1992 vfs_opterror(opts, "unknown parameter: %s", opt->name);
1993 goto done_deref;
1994 }
1995 }
1996 maybe_changed = true;
1997
1998 /* Set the parameters of the prison. */
1999 #ifdef INET
2000 redo_ip4 = false;
2001 if (pr_flags & PR_IP4_USER) {
2002 pr->pr_flags |= PR_IP4;
2003 prison_ip_set(pr, PR_INET, ip4);
2004 ip4 = NULL;
2005 FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
2006 #ifdef VIMAGE
2007 if (tpr->pr_flags & PR_VNET) {
2008 descend = 0;
2009 continue;
2010 }
2011 #endif
2012 if (!prison_ip_restrict(tpr, PR_INET, NULL)) {
2013 redo_ip4 = true;
2014 descend = 0;
2015 }
2016 }
2017 }
2018 #endif
2019 #ifdef INET6
2020 redo_ip6 = false;
2021 if (pr_flags & PR_IP6_USER) {
2022 pr->pr_flags |= PR_IP6;
2023 prison_ip_set(pr, PR_INET6, ip6);
2024 ip6 = NULL;
2025 FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
2026 #ifdef VIMAGE
2027 if (tpr->pr_flags & PR_VNET) {
2028 descend = 0;
2029 continue;
2030 }
2031 #endif
2032 if (!prison_ip_restrict(tpr, PR_INET6, NULL)) {
2033 redo_ip6 = true;
2034 descend = 0;
2035 }
2036 }
2037 }
2038 #endif
2039 if (gotslevel) {
2040 pr->pr_securelevel = slevel;
2041 /* Set all child jails to be at least this level. */
2042 FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend)
2043 if (tpr->pr_securelevel < slevel)
2044 tpr->pr_securelevel = slevel;
2045 }
2046 if (gotchildmax) {
2047 pr->pr_childmax = childmax;
2048 /* Set all child jails to under this limit. */
2049 FOREACH_PRISON_DESCENDANT_LOCKED_LEVEL(pr, tpr, descend, level)
2050 if (tpr->pr_childmax > childmax - level)
2051 tpr->pr_childmax = childmax > level
2052 ? childmax - level : 0;
2053 }
2054 if (gotenforce) {
2055 pr->pr_enforce_statfs = enforce;
2056 /* Pass this restriction on to the children. */
2057 FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend)
2058 if (tpr->pr_enforce_statfs < enforce)
2059 tpr->pr_enforce_statfs = enforce;
2060 }
2061 if (gotrsnum) {
2062 pr->pr_devfs_rsnum = rsnum;
2063 /* Pass this restriction on to the children. */
2064 FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend)
2065 tpr->pr_devfs_rsnum = rsnum;
2066 }
2067 if (namelc != NULL) {
2068 if (ppr == &prison0)
2069 strlcpy(pr->pr_name, namelc, sizeof(pr->pr_name));
2070 else
2071 snprintf(pr->pr_name, sizeof(pr->pr_name), "%s.%s",
2072 ppr->pr_name, namelc);
2073 /* Change this component of child names. */
2074 FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
2075 bcopy(tpr->pr_name + onamelen, tpr->pr_name + namelen,
2076 strlen(tpr->pr_name + onamelen) + 1);
2077 bcopy(pr->pr_name, tpr->pr_name, namelen);
2078 }
2079 }
2080 if (path != NULL) {
2081 /* Try to keep a real-rooted full pathname. */
2082 strlcpy(pr->pr_path, path, sizeof(pr->pr_path));
2083 pr->pr_root = root;
2084 root = NULL;
2085 }
2086 if (PR_HOST & ch_flags & ~pr_flags) {
2087 if (pr->pr_flags & PR_HOST) {
2088 /*
2089 * Copy the parent's host info. As with pr_ip4 above,
2090 * the lack of a lock on the parent is not a problem;
2091 * it is always set with allprison_lock at least
2092 * shared, and is held exclusively here.
2093 */
2094 strlcpy(pr->pr_hostname, pr->pr_parent->pr_hostname,
2095 sizeof(pr->pr_hostname));
2096 strlcpy(pr->pr_domainname, pr->pr_parent->pr_domainname,
2097 sizeof(pr->pr_domainname));
2098 strlcpy(pr->pr_hostuuid, pr->pr_parent->pr_hostuuid,
2099 sizeof(pr->pr_hostuuid));
2100 pr->pr_hostid = pr->pr_parent->pr_hostid;
2101 }
2102 } else if (host != NULL || domain != NULL || uuid != NULL || gothid) {
2103 /* Set this prison, and any descendants without PR_HOST. */
2104 if (host != NULL)
2105 strlcpy(pr->pr_hostname, host, sizeof(pr->pr_hostname));
2106 if (domain != NULL)
2107 strlcpy(pr->pr_domainname, domain,
2108 sizeof(pr->pr_domainname));
2109 if (uuid != NULL)
2110 strlcpy(pr->pr_hostuuid, uuid, sizeof(pr->pr_hostuuid));
2111 if (gothid)
2112 pr->pr_hostid = hid;
2113 FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
2114 if (tpr->pr_flags & PR_HOST)
2115 descend = 0;
2116 else {
2117 if (host != NULL)
2118 strlcpy(tpr->pr_hostname,
2119 pr->pr_hostname,
2120 sizeof(tpr->pr_hostname));
2121 if (domain != NULL)
2122 strlcpy(tpr->pr_domainname,
2123 pr->pr_domainname,
2124 sizeof(tpr->pr_domainname));
2125 if (uuid != NULL)
2126 strlcpy(tpr->pr_hostuuid,
2127 pr->pr_hostuuid,
2128 sizeof(tpr->pr_hostuuid));
2129 if (gothid)
2130 tpr->pr_hostid = hid;
2131 }
2132 }
2133 }
2134 pr->pr_allow = (pr->pr_allow & ~ch_allow) | pr_allow;
2135 if ((tallow = ch_allow & ~pr_allow))
2136 prison_set_allow_locked(pr, tallow, 0);
2137 /*
2138 * Persistent prisons get an extra reference, and prisons losing their
2139 * persist flag lose that reference.
2140 */
2141 if (ch_flags & PR_PERSIST & (pr_flags ^ pr->pr_flags)) {
2142 if (pr_flags & PR_PERSIST) {
2143 prison_hold(pr);
2144 /*
2145 * This may be a new prison's first user reference,
2146 * but wait to call it alive until after OSD calls
2147 * have had a chance to run (and perhaps to fail).
2148 */
2149 refcount_acquire(&pr->pr_uref);
2150 } else {
2151 drflags |= PD_DEUREF;
2152 prison_free_not_last(pr);
2153 }
2154 }
2155 pr->pr_flags = (pr->pr_flags & ~ch_flags) | pr_flags;
2156 mtx_unlock(&pr->pr_mtx);
2157 drflags &= ~PD_LOCKED;
2158 /*
2159 * Any errors past this point will need to de-persist newly created
2160 * prisons, as well as call remove methods.
2161 */
2162 if (created)
2163 drflags |= PD_KILL;
2164
2165 #ifdef RACCT
2166 if (racct_enable && created)
2167 prison_racct_attach(pr);
2168 #endif
2169
2170 /* Locks may have prevented a complete restriction of child IP
2171 * addresses. If so, allocate some more memory and try again.
2172 */
2173 #ifdef INET
2174 while (redo_ip4) {
2175 ip4s = pr->pr_addrs[PR_INET]->ips;
2176 MPASS(ip4 == NULL);
2177 ip4 = prison_ip_alloc(PR_INET, ip4s, M_WAITOK);
2178 mtx_lock(&pr->pr_mtx);
2179 redo_ip4 = false;
2180 FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
2181 #ifdef VIMAGE
2182 if (tpr->pr_flags & PR_VNET) {
2183 descend = 0;
2184 continue;
2185 }
2186 #endif
2187 if (!prison_ip_restrict(tpr, PR_INET, &ip4))
2188 redo_ip4 = true;
2189 }
2190 mtx_unlock(&pr->pr_mtx);
2191 }
2192 #endif
2193 #ifdef INET6
2194 while (redo_ip6) {
2195 ip6s = pr->pr_addrs[PR_INET6]->ips;
2196 MPASS(ip6 == NULL);
2197 ip6 = prison_ip_alloc(PR_INET6, ip6s, M_WAITOK);
2198 mtx_lock(&pr->pr_mtx);
2199 redo_ip6 = false;
2200 FOREACH_PRISON_DESCENDANT_LOCKED(pr, tpr, descend) {
2201 #ifdef VIMAGE
2202 if (tpr->pr_flags & PR_VNET) {
2203 descend = 0;
2204 continue;
2205 }
2206 #endif
2207 if (!prison_ip_restrict(tpr, PR_INET6, &ip6))
2208 redo_ip6 = true;
2209 }
2210 mtx_unlock(&pr->pr_mtx);
2211 }
2212 #endif
2213
2214 /* Let the modules do their work. */
2215 if (created) {
2216 error = osd_jail_call(pr, PR_METHOD_CREATE, opts);
2217 if (error)
2218 goto done_deref;
2219 }
2220 error = osd_jail_call(pr, PR_METHOD_SET, opts);
2221 if (error)
2222 goto done_deref;
2223
2224 /*
2225 * A new prison is now ready to be seen; either it has gained a user
2226 * reference via persistence, or is about to gain one via attachment.
2227 */
2228 if (created) {
2229 sx_assert(&allprison_lock, SX_XLOCKED);
2230 prison_knote(ppr, NOTE_JAIL_CHILD | pr->pr_id);
2231 mtx_lock(&pr->pr_mtx);
2232 drflags |= PD_LOCKED;
2233 pr->pr_state = PRISON_STATE_ALIVE;
2234 }
2235
2236 /* Attach this process to the prison if requested. */
2237 if (flags & JAIL_ATTACH) {
2238 error = do_jail_attach(td, pr,
2239 prison_lock_xlock(pr, drflags & PD_LOCK_FLAGS));
2240 drflags &= ~(PD_LOCKED | PD_LIST_XLOCKED);
2241 if (error) {
2242 vfs_opterror(opts, "attach failed");
2243 goto done_deref;
2244 }
2245 }
2246
2247 #ifdef RACCT
2248 if (racct_enable && !created) {
2249 if (drflags & PD_LOCKED) {
2250 mtx_unlock(&pr->pr_mtx);
2251 drflags &= ~PD_LOCKED;
2252 }
2253 if (drflags & PD_LIST_XLOCKED) {
2254 sx_xunlock(&allprison_lock);
2255 drflags &= ~PD_LIST_XLOCKED;
2256 }
2257 prison_racct_modify(pr);
2258 }
2259 #endif
2260
2261 if (created && pr != &prison0 && (pr->pr_allow & PR_ALLOW_NFSD) != 0 &&
2262 (pr->pr_root->v_vflag & VV_ROOT) == 0)
2263 printf("Warning jail jid=%d: mountd/nfsd requires a separate"
2264 " file system\n", pr->pr_id);
2265
2266 /*
2267 * Now that the prison is fully created without error, set the
2268 * jail descriptor if one was requested. This is the only
2269 * parameter that is returned to the caller (except the error
2270 * message).
2271 */
2272 if (jfd_out >= 0) {
2273 if (!(drflags & PD_LOCKED)) {
2274 mtx_lock(&pr->pr_mtx);
2275 drflags |= PD_LOCKED;
2276 }
2277 jfd_pos = 2 * vfs_getopt_pos(opts, "desc") + 1;
2278 if (optuio->uio_segflg == UIO_SYSSPACE)
2279 *(int*)optuio->uio_iov[jfd_pos].iov_base = jfd_out;
2280 else
2281 (void)copyout(&jfd_out,
2282 optuio->uio_iov[jfd_pos].iov_base, sizeof(jfd_out));
2283 jaildesc_set_prison(jfp_out, pr);
2284 }
2285
2286 drflags &= ~PD_KILL;
2287 td->td_retval[0] = pr->pr_id;
2288
2289 done_deref:
2290 /*
2291 * Report changes to kevent. This can happen even if the
2292 * system call fails, as changes might have been made before
2293 * the failure.
2294 */
2295 if (maybe_changed && !created)
2296 prison_knote(pr, NOTE_JAIL_SET);
2297 /* Release any temporary prison holds and/or locks. */
2298 if (pr != NULL)
2299 prison_deref(pr, drflags);
2300 else if (drflags & PD_LIST_SLOCKED)
2301 sx_sunlock(&allprison_lock);
2302 else if (drflags & PD_LIST_XLOCKED)
2303 sx_xunlock(&allprison_lock);
2304 if (root != NULL)
2305 vrele(root);
2306 done_errmsg:
2307 if (error) {
2308 /* Write the error message back to userspace. */
2309 if (vfs_getopt(opts, "errmsg", (void **)&errmsg,
2310 &errmsg_len) == 0 && errmsg_len > 0) {
2311 errmsg_pos = 2 * vfs_getopt_pos(opts, "errmsg") + 1;
2312 if (optuio->uio_segflg == UIO_SYSSPACE)
2313 bcopy(errmsg,
2314 optuio->uio_iov[errmsg_pos].iov_base,
2315 errmsg_len);
2316 else
2317 (void)copyout(errmsg,
2318 optuio->uio_iov[errmsg_pos].iov_base,
2319 errmsg_len);
2320 }
2321 }
2322 done_free:
2323 /* Clean up other resources. */
2324 #ifdef INET
2325 prison_ip_free(ip4);
2326 #endif
2327 #ifdef INET6
2328 prison_ip_free(ip6);
2329 #endif
2330 if (jfp_out != NULL)
2331 fdrop(jfp_out, td);
2332 if (error && jfd_out >= 0)
2333 (void)kern_close(td, jfd_out);
2334 if (g_path != NULL)
2335 free(g_path, M_TEMP);
2336 if (opts != NULL)
2337 vfs_freeopts(opts);
2338 prison_free(mypr);
2339 return (error);
2340 }
2341
2342 /*
2343 * Find the next available prison ID. Return the ID on success, or zero
2344 * on failure. Also set a pointer to the allprison list entry the prison
2345 * should be inserted before.
2346 */
2347 static int
get_next_prid(struct prison ** insprp)2348 get_next_prid(struct prison **insprp)
2349 {
2350 struct prison *inspr;
2351 int jid, maxid;
2352
2353 jid = lastprid % JAIL_MAX + 1;
2354 if (TAILQ_EMPTY(&allprison) ||
2355 TAILQ_LAST(&allprison, prisonlist)->pr_id < jid) {
2356 /*
2357 * A common case is for all jails to be implicitly numbered,
2358 * which means they'll go on the end of the list, at least
2359 * for the first JAIL_MAX times.
2360 */
2361 inspr = NULL;
2362 } else {
2363 /*
2364 * Take two passes through the allprison list: first starting
2365 * with the proposed jid, then ending with it.
2366 */
2367 for (maxid = JAIL_MAX; maxid != 0; ) {
2368 TAILQ_FOREACH(inspr, &allprison, pr_list) {
2369 if (inspr->pr_id < jid)
2370 continue;
2371 if (inspr->pr_id > jid) {
2372 /* Found an opening. */
2373 maxid = 0;
2374 break;
2375 }
2376 if (++jid > maxid) {
2377 if (lastprid == maxid || lastprid == 0)
2378 {
2379 /*
2380 * The entire legal range
2381 * has been traversed
2382 */
2383 return 0;
2384 }
2385 /* Try again from the start. */
2386 jid = 1;
2387 maxid = lastprid;
2388 break;
2389 }
2390 }
2391 if (inspr == NULL) {
2392 /* Found room at the end of the list. */
2393 break;
2394 }
2395 }
2396 }
2397 *insprp = inspr;
2398 lastprid = jid;
2399 return (jid);
2400 }
2401
2402 /*
2403 * Find the next available ID for a renumbered dead prison. This is the same
2404 * as get_next_prid, but counting backward from the end of the range.
2405 */
2406 static int
get_next_deadid(struct prison ** dinsprp)2407 get_next_deadid(struct prison **dinsprp)
2408 {
2409 struct prison *dinspr;
2410 int deadid, minid;
2411
2412 deadid = lastdeadid ? lastdeadid - 1 : JAIL_MAX;
2413 /*
2414 * Take two reverse passes through the allprison list: first
2415 * starting with the proposed deadid, then ending with it.
2416 */
2417 for (minid = 1; minid != 0; ) {
2418 TAILQ_FOREACH_REVERSE(dinspr, &allprison, prisonlist, pr_list) {
2419 if (dinspr->pr_id > deadid)
2420 continue;
2421 if (dinspr->pr_id < deadid) {
2422 /* Found an opening. */
2423 minid = 0;
2424 break;
2425 }
2426 if (--deadid < minid) {
2427 if (lastdeadid == minid || lastdeadid == 0)
2428 {
2429 /*
2430 * The entire legal range
2431 * has been traversed
2432 */
2433 return 0;
2434 }
2435 /* Try again from the end. */
2436 deadid = JAIL_MAX;
2437 minid = lastdeadid;
2438 break;
2439 }
2440 }
2441 if (dinspr == NULL) {
2442 /* Found room at the beginning of the list. */
2443 break;
2444 }
2445 }
2446 *dinsprp = dinspr;
2447 lastdeadid = deadid;
2448 return (deadid);
2449 }
2450
2451 /*
2452 * struct jail_get_args {
2453 * struct iovec *iovp;
2454 * unsigned int iovcnt;
2455 * int flags;
2456 * };
2457 */
2458 int
sys_jail_get(struct thread * td,struct jail_get_args * uap)2459 sys_jail_get(struct thread *td, struct jail_get_args *uap)
2460 {
2461 struct uio *auio;
2462 int error;
2463
2464 /* Check that we have an even number of iovecs. */
2465 if (uap->iovcnt & 1)
2466 return (EINVAL);
2467
2468 error = copyinuio(uap->iovp, uap->iovcnt, &auio);
2469 if (error)
2470 return (error);
2471 error = kern_jail_get(td, auio, uap->flags);
2472 if (error == 0)
2473 error = copyout(auio->uio_iov, uap->iovp,
2474 uap->iovcnt * sizeof(struct iovec));
2475 freeuio(auio);
2476 return (error);
2477 }
2478
2479 int
kern_jail_get(struct thread * td,struct uio * optuio,int flags)2480 kern_jail_get(struct thread *td, struct uio *optuio, int flags)
2481 {
2482 struct bool_flags *bf;
2483 struct file *jfp_out;
2484 struct jailsys_flags *jsf;
2485 struct prison *pr, *mypr;
2486 struct vfsopt *opt;
2487 struct vfsoptlist *opts;
2488 char *errmsg, *name;
2489 int drflags, error, errmsg_len, errmsg_pos, i, jid, len, pos;
2490 int jfd_in, jfd_out;
2491 unsigned f;
2492
2493 if (flags & ~JAIL_GET_MASK)
2494 return (EINVAL);
2495 if ((flags & (JAIL_USE_DESC | JAIL_AT_DESC)) ==
2496 (JAIL_USE_DESC | JAIL_AT_DESC))
2497 return (EINVAL);
2498
2499 /* Get the parameter list. */
2500 error = vfs_buildopts(optuio, &opts);
2501 if (error)
2502 return (error);
2503 errmsg_pos = vfs_getopt_pos(opts, "errmsg");
2504 mypr = td->td_ucred->cr_prison;
2505 prison_hold(mypr);
2506 pr = NULL;
2507 jfp_out = NULL;
2508 jfd_out = -1;
2509
2510 /*
2511 * Find the prison specified by one of: desc, lastjid, jid, name.
2512 */
2513 sx_slock(&allprison_lock);
2514 drflags = PD_LIST_SLOCKED;
2515
2516 error = vfs_copyopt(opts, "desc", &jfd_in, sizeof(jfd_in));
2517 if (error == ENOENT) {
2518 if (flags & (JAIL_AT_DESC | JAIL_GET_DESC | JAIL_OWN_DESC)) {
2519 vfs_opterror(opts, "missing desc");
2520 goto done;
2521 }
2522 } else if (error == 0) {
2523 if (!(flags & (JAIL_USE_DESC | JAIL_AT_DESC | JAIL_GET_DESC |
2524 JAIL_OWN_DESC))) {
2525 error = EINVAL;
2526 vfs_opterror(opts, "unexpected desc");
2527 goto done;
2528 }
2529 if (flags & JAIL_USE_DESC) {
2530 /* Get the jail from its descriptor. */
2531 error = jaildesc_find(td, jfd_in, &pr, NULL);
2532 if (error) {
2533 vfs_opterror(opts, error == ENOENT ?
2534 "descriptor to dead jail" :
2535 "not a jail descriptor");
2536 goto done;
2537 }
2538 drflags |= PD_DEREF;
2539 mtx_lock(&pr->pr_mtx);
2540 drflags |= PD_LOCKED;
2541 if (!(prison_isalive(pr) || (flags & JAIL_DYING))) {
2542 error = ENOENT;
2543 vfs_opterror(opts, "jail %d is dying",
2544 pr->pr_id);
2545 goto done;
2546 }
2547 goto found_prison;
2548 }
2549 if (flags & JAIL_AT_DESC) {
2550 /* Look up jails based on the descriptor's prison. */
2551 prison_free(mypr);
2552 error = jaildesc_find(td, jfd_in, &mypr, NULL);
2553 if (error != 0) {
2554 vfs_opterror(opts, error == ENOENT ?
2555 "descriptor to dead jail" :
2556 "not a jail descriptor");
2557 goto done;
2558 }
2559 }
2560 if (flags & (JAIL_GET_DESC | JAIL_OWN_DESC)) {
2561 /* Allocate a jail descriptor to return later. */
2562 error = jaildesc_alloc(td, &jfp_out, &jfd_out,
2563 flags & JAIL_OWN_DESC);
2564 if (error)
2565 goto done;
2566 }
2567 } else
2568 goto done;
2569
2570 error = vfs_copyopt(opts, "lastjid", &jid, sizeof(jid));
2571 if (error == 0) {
2572 TAILQ_FOREACH(pr, &allprison, pr_list) {
2573 if (pr->pr_id > jid &&
2574 ((flags & JAIL_DYING) || prison_isalive(pr)) &&
2575 prison_ischild(mypr, pr)) {
2576 mtx_lock(&pr->pr_mtx);
2577 drflags |= PD_LOCKED;
2578 goto found_prison;
2579 }
2580 }
2581 error = ENOENT;
2582 vfs_opterror(opts, "no jail after %d", jid);
2583 goto done;
2584 } else if (error != ENOENT)
2585 goto done;
2586
2587 error = vfs_copyopt(opts, "jid", &jid, sizeof(jid));
2588 if (error == 0) {
2589 if (jid != 0) {
2590 pr = prison_find_child(mypr, jid);
2591 if (pr != NULL) {
2592 drflags |= PD_LOCKED;
2593 if (!(prison_isalive(pr) ||
2594 (flags & JAIL_DYING))) {
2595 error = ENOENT;
2596 vfs_opterror(opts, "jail %d is dying",
2597 jid);
2598 goto done;
2599 }
2600 goto found_prison;
2601 }
2602 error = ENOENT;
2603 vfs_opterror(opts, "jail %d not found", jid);
2604 goto done;
2605 }
2606 } else if (error != ENOENT)
2607 goto done;
2608
2609 error = vfs_getopt(opts, "name", (void **)&name, &len);
2610 if (error == 0) {
2611 if (len == 0 || name[len - 1] != '\0') {
2612 error = EINVAL;
2613 goto done;
2614 }
2615 pr = prison_find_name(mypr, name);
2616 if (pr != NULL) {
2617 drflags |= PD_LOCKED;
2618 if (!(prison_isalive(pr) || (flags & JAIL_DYING))) {
2619 error = ENOENT;
2620 vfs_opterror(opts, "jail \"%s\" is dying",
2621 name);
2622 goto done;
2623 }
2624 goto found_prison;
2625 }
2626 error = ENOENT;
2627 vfs_opterror(opts, "jail \"%s\" not found", name);
2628 goto done;
2629 } else if (error != ENOENT)
2630 goto done;
2631
2632 vfs_opterror(opts, "no jail specified");
2633 error = ENOENT;
2634 goto done;
2635
2636 found_prison:
2637 /* Get the parameters of the prison. */
2638 if (!(drflags & PD_DEREF)) {
2639 prison_hold(pr);
2640 drflags |= PD_DEREF;
2641 }
2642 td->td_retval[0] = pr->pr_id;
2643 if (jfd_out >= 0) {
2644 error = vfs_setopt(opts, "desc", &jfd_out, sizeof(jfd_out));
2645 if (error != 0 && error != ENOENT)
2646 goto done;
2647 jaildesc_set_prison(jfp_out, pr);
2648 }
2649 error = vfs_setopt(opts, "jid", &pr->pr_id, sizeof(pr->pr_id));
2650 if (error != 0 && error != ENOENT)
2651 goto done;
2652 i = (pr->pr_parent == mypr) ? 0 : pr->pr_parent->pr_id;
2653 error = vfs_setopt(opts, "parent", &i, sizeof(i));
2654 if (error != 0 && error != ENOENT)
2655 goto done;
2656 error = vfs_setopts(opts, "name", prison_name(mypr, pr));
2657 if (error != 0 && error != ENOENT)
2658 goto done;
2659 error = vfs_setopt(opts, "cpuset.id", &pr->pr_cpuset->cs_id,
2660 sizeof(pr->pr_cpuset->cs_id));
2661 if (error != 0 && error != ENOENT)
2662 goto done;
2663 error = vfs_setopts(opts, "path", prison_path(mypr, pr));
2664 if (error != 0 && error != ENOENT)
2665 goto done;
2666 #ifdef INET
2667 error = vfs_setopt_part(opts, "ip4.addr", pr->pr_addrs[PR_INET]->pr_ip,
2668 pr->pr_addrs[PR_INET] ? pr->pr_addrs[PR_INET]->ips *
2669 pr_families[PR_INET].size : 0 );
2670 if (error != 0 && error != ENOENT)
2671 goto done;
2672 #endif
2673 #ifdef INET6
2674 error = vfs_setopt_part(opts, "ip6.addr", pr->pr_addrs[PR_INET6]->pr_ip,
2675 pr->pr_addrs[PR_INET6] ? pr->pr_addrs[PR_INET6]->ips *
2676 pr_families[PR_INET6].size : 0 );
2677 if (error != 0 && error != ENOENT)
2678 goto done;
2679 #endif
2680 error = vfs_setopt(opts, "securelevel", &pr->pr_securelevel,
2681 sizeof(pr->pr_securelevel));
2682 if (error != 0 && error != ENOENT)
2683 goto done;
2684 error = vfs_setopt(opts, "children.cur", &pr->pr_childcount,
2685 sizeof(pr->pr_childcount));
2686 if (error != 0 && error != ENOENT)
2687 goto done;
2688 error = vfs_setopt(opts, "children.max", &pr->pr_childmax,
2689 sizeof(pr->pr_childmax));
2690 if (error != 0 && error != ENOENT)
2691 goto done;
2692 error = vfs_setopts(opts, "host.hostname", pr->pr_hostname);
2693 if (error != 0 && error != ENOENT)
2694 goto done;
2695 error = vfs_setopts(opts, "host.domainname", pr->pr_domainname);
2696 if (error != 0 && error != ENOENT)
2697 goto done;
2698 error = vfs_setopts(opts, "host.hostuuid", pr->pr_hostuuid);
2699 if (error != 0 && error != ENOENT)
2700 goto done;
2701 #ifdef COMPAT_FREEBSD32
2702 if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
2703 uint32_t hid32 = pr->pr_hostid;
2704
2705 error = vfs_setopt(opts, "host.hostid", &hid32, sizeof(hid32));
2706 } else
2707 #endif
2708 error = vfs_setopt(opts, "host.hostid", &pr->pr_hostid,
2709 sizeof(pr->pr_hostid));
2710 if (error != 0 && error != ENOENT)
2711 goto done;
2712 error = vfs_setopt(opts, "enforce_statfs", &pr->pr_enforce_statfs,
2713 sizeof(pr->pr_enforce_statfs));
2714 if (error != 0 && error != ENOENT)
2715 goto done;
2716 error = vfs_setopt(opts, "devfs_ruleset", &pr->pr_devfs_rsnum,
2717 sizeof(pr->pr_devfs_rsnum));
2718 if (error != 0 && error != ENOENT)
2719 goto done;
2720 for (bf = pr_flag_bool;
2721 bf < pr_flag_bool + nitems(pr_flag_bool);
2722 bf++) {
2723 i = (pr->pr_flags & bf->flag) ? 1 : 0;
2724 error = vfs_setopt(opts, bf->name, &i, sizeof(i));
2725 if (error != 0 && error != ENOENT)
2726 goto done;
2727 i = !i;
2728 error = vfs_setopt(opts, bf->noname, &i, sizeof(i));
2729 if (error != 0 && error != ENOENT)
2730 goto done;
2731 }
2732 for (jsf = pr_flag_jailsys;
2733 jsf < pr_flag_jailsys + nitems(pr_flag_jailsys);
2734 jsf++) {
2735 f = pr->pr_flags & (jsf->disable | jsf->new);
2736 i = (f != 0 && f == jsf->disable) ? JAIL_SYS_DISABLE
2737 : (f == jsf->new) ? JAIL_SYS_NEW
2738 : JAIL_SYS_INHERIT;
2739 error = vfs_setopt(opts, jsf->name, &i, sizeof(i));
2740 if (error != 0 && error != ENOENT)
2741 goto done;
2742 }
2743 for (bf = pr_flag_allow;
2744 bf < pr_flag_allow + nitems(pr_flag_allow) &&
2745 atomic_load_int(&bf->flag) != 0;
2746 bf++) {
2747 i = (pr->pr_allow & bf->flag) ? 1 : 0;
2748 error = vfs_setopt(opts, bf->name, &i, sizeof(i));
2749 if (error != 0 && error != ENOENT)
2750 goto done;
2751 i = !i;
2752 error = vfs_setopt(opts, bf->noname, &i, sizeof(i));
2753 if (error != 0 && error != ENOENT)
2754 goto done;
2755 }
2756 i = !prison_isalive(pr);
2757 error = vfs_setopt(opts, "dying", &i, sizeof(i));
2758 if (error != 0 && error != ENOENT)
2759 goto done;
2760 i = !i;
2761 error = vfs_setopt(opts, "nodying", &i, sizeof(i));
2762 if (error != 0 && error != ENOENT)
2763 goto done;
2764 error = vfs_setopt(opts, "osreldate", &pr->pr_osreldate,
2765 sizeof(pr->pr_osreldate));
2766 if (error != 0 && error != ENOENT)
2767 goto done;
2768 error = vfs_setopts(opts, "osrelease", pr->pr_osrelease);
2769 if (error != 0 && error != ENOENT)
2770 goto done;
2771
2772 /* Get the module parameters. */
2773 mtx_unlock(&pr->pr_mtx);
2774 drflags &= ~PD_LOCKED;
2775 error = osd_jail_call(pr, PR_METHOD_GET, opts);
2776 if (error)
2777 goto done;
2778 prison_deref(pr, drflags);
2779 pr = NULL;
2780 drflags = 0;
2781
2782 /* By now, all parameters should have been noted. */
2783 TAILQ_FOREACH(opt, opts, link) {
2784 if (!opt->seen &&
2785 (strstr(opt->name, JAIL_META_PRIVATE ".") == opt->name ||
2786 strstr(opt->name, JAIL_META_SHARED ".") == opt->name)) {
2787 /* Communicate back a missing key. */
2788 free(opt->value, M_MOUNT);
2789 opt->value = NULL;
2790 opt->len = 0;
2791 continue;
2792 }
2793 if (!opt->seen && strcmp(opt->name, "errmsg")) {
2794 error = EINVAL;
2795 vfs_opterror(opts, "unknown parameter: %s", opt->name);
2796 goto done;
2797 }
2798 }
2799
2800 /* Write the fetched parameters back to userspace. */
2801 error = 0;
2802 TAILQ_FOREACH(opt, opts, link) {
2803 if (opt->pos >= 0 && opt->pos != errmsg_pos) {
2804 pos = 2 * opt->pos + 1;
2805 optuio->uio_iov[pos].iov_len = opt->len;
2806 if (opt->value != NULL) {
2807 if (optuio->uio_segflg == UIO_SYSSPACE) {
2808 bcopy(opt->value,
2809 optuio->uio_iov[pos].iov_base,
2810 opt->len);
2811 } else {
2812 error = copyout(opt->value,
2813 optuio->uio_iov[pos].iov_base,
2814 opt->len);
2815 if (error)
2816 break;
2817 }
2818 }
2819 }
2820 }
2821
2822 done:
2823 /* Release any temporary prison holds and/or locks. */
2824 if (pr != NULL)
2825 prison_deref(pr, drflags);
2826 else if (drflags & PD_LIST_SLOCKED)
2827 sx_sunlock(&allprison_lock);
2828 else if (drflags & PD_LIST_XLOCKED)
2829 sx_xunlock(&allprison_lock);
2830 /* Clean up other resources. */
2831 if (jfp_out != NULL)
2832 (void)fdrop(jfp_out, td);
2833 if (error && jfd_out >= 0)
2834 (void)kern_close(td, jfd_out);
2835 if (error && errmsg_pos >= 0) {
2836 /* Write the error message back to userspace. */
2837 vfs_getopt(opts, "errmsg", (void **)&errmsg, &errmsg_len);
2838 errmsg_pos = 2 * errmsg_pos + 1;
2839 if (errmsg_len > 0) {
2840 if (optuio->uio_segflg == UIO_SYSSPACE)
2841 bcopy(errmsg,
2842 optuio->uio_iov[errmsg_pos].iov_base,
2843 errmsg_len);
2844 else
2845 (void)copyout(errmsg,
2846 optuio->uio_iov[errmsg_pos].iov_base,
2847 errmsg_len);
2848 }
2849 }
2850 vfs_freeopts(opts);
2851 prison_free(mypr);
2852 return (error);
2853 }
2854
2855 /*
2856 * struct jail_remove_args {
2857 * int jid;
2858 * };
2859 */
2860 int
sys_jail_remove(struct thread * td,struct jail_remove_args * uap)2861 sys_jail_remove(struct thread *td, struct jail_remove_args *uap)
2862 {
2863 struct prison *pr;
2864 int error;
2865
2866 error = priv_check(td, PRIV_JAIL_REMOVE);
2867 if (error)
2868 return (error);
2869
2870 sx_xlock(&allprison_lock);
2871 pr = prison_find_child(td->td_ucred->cr_prison, uap->jid);
2872 if (pr == NULL) {
2873 sx_xunlock(&allprison_lock);
2874 return (EINVAL);
2875 }
2876 prison_hold(pr);
2877 prison_remove(pr);
2878 return (0);
2879 }
2880
2881 /*
2882 * struct jail_remove_jd_args {
2883 * int fd;
2884 * };
2885 */
2886 int
sys_jail_remove_jd(struct thread * td,struct jail_remove_jd_args * uap)2887 sys_jail_remove_jd(struct thread *td, struct jail_remove_jd_args *uap)
2888 {
2889 struct prison *pr;
2890 struct ucred *jdcred;
2891 int error;
2892
2893 error = jaildesc_find(td, uap->fd, &pr, &jdcred);
2894 if (error)
2895 return (error);
2896 error = priv_check_cred(jdcred, PRIV_JAIL_REMOVE);
2897 crfree(jdcred);
2898 if (error) {
2899 prison_free(pr);
2900 return (error);
2901 }
2902 sx_xlock(&allprison_lock);
2903 mtx_lock(&pr->pr_mtx);
2904 prison_remove(pr);
2905 return (0);
2906 }
2907
2908 /*
2909 * Begin the removal process for a prison. The allprison lock should
2910 * be held exclusively, and the prison should be both locked and held.
2911 */
2912 void
prison_remove(struct prison * pr)2913 prison_remove(struct prison *pr)
2914 {
2915 sx_assert(&allprison_lock, SA_XLOCKED);
2916 mtx_assert(&pr->pr_mtx, MA_OWNED);
2917 prison_deref(pr, PD_KILL | PD_DEREF | PD_LOCKED | PD_LIST_XLOCKED);
2918 }
2919
2920 /*
2921 * struct jail_attach_args {
2922 * int jid;
2923 * };
2924 */
2925 int
sys_jail_attach(struct thread * td,struct jail_attach_args * uap)2926 sys_jail_attach(struct thread *td, struct jail_attach_args *uap)
2927 {
2928 struct prison *pr;
2929 int error;
2930
2931 error = priv_check(td, PRIV_JAIL_ATTACH);
2932 if (error)
2933 return (error);
2934
2935 sx_slock(&allprison_lock);
2936 pr = prison_find_child(td->td_ucred->cr_prison, uap->jid);
2937 if (pr == NULL) {
2938 sx_sunlock(&allprison_lock);
2939 return (EINVAL);
2940 }
2941
2942 /* Do not allow a process to attach to a prison that is not alive. */
2943 if (!prison_isalive(pr)) {
2944 mtx_unlock(&pr->pr_mtx);
2945 sx_sunlock(&allprison_lock);
2946 return (EINVAL);
2947 }
2948
2949 return (do_jail_attach(td, pr, PD_LOCKED | PD_LIST_SLOCKED));
2950 }
2951
2952 /*
2953 * struct jail_attach_jd_args {
2954 * int fd;
2955 * };
2956 */
2957 int
sys_jail_attach_jd(struct thread * td,struct jail_attach_jd_args * uap)2958 sys_jail_attach_jd(struct thread *td, struct jail_attach_jd_args *uap)
2959 {
2960 struct prison *pr;
2961 struct ucred *jdcred;
2962 int drflags, error;
2963
2964 sx_slock(&allprison_lock);
2965 drflags = PD_LIST_SLOCKED;
2966 error = jaildesc_find(td, uap->fd, &pr, &jdcred);
2967 if (error)
2968 goto fail;
2969 drflags |= PD_DEREF;
2970 error = priv_check_cred(jdcred, PRIV_JAIL_ATTACH);
2971 crfree(jdcred);
2972 if (error)
2973 goto fail;
2974 mtx_lock(&pr->pr_mtx);
2975 drflags |= PD_LOCKED;
2976
2977 /* Do not allow a process to attach to a prison that is not alive. */
2978 if (!prison_isalive(pr)) {
2979 error = EINVAL;
2980 goto fail;
2981 }
2982
2983 return (do_jail_attach(td, pr, drflags));
2984
2985 fail:
2986 prison_deref(pr, drflags);
2987 return (error);
2988 }
2989
2990 static int
do_jail_attach(struct thread * td,struct prison * pr,int drflags)2991 do_jail_attach(struct thread *td, struct prison *pr, int drflags)
2992 {
2993 struct proc *p;
2994 struct ucred *newcred, *oldcred;
2995 int error;
2996
2997 mtx_assert(&pr->pr_mtx, MA_OWNED);
2998 sx_assert(&allprison_lock, SX_LOCKED);
2999 drflags &= PD_LOCK_FLAGS;
3000 /*
3001 * XXX: Note that there is a slight race here if two threads
3002 * in the same privileged process attempt to attach to two
3003 * different jails at the same time. It is important for
3004 * user processes not to do this, or they might end up with
3005 * a process root from one prison, but attached to the jail
3006 * of another.
3007 */
3008 if (!(drflags & PD_DEREF)) {
3009 prison_hold(pr);
3010 drflags |= PD_DEREF;
3011 }
3012 refcount_acquire(&pr->pr_uref);
3013 drflags |= PD_DEUREF;
3014 mtx_unlock(&pr->pr_mtx);
3015 drflags &= ~PD_LOCKED;
3016
3017 /* Let modules do whatever they need to prepare for attaching. */
3018 error = osd_jail_call(pr, PR_METHOD_ATTACH, td);
3019 if (error) {
3020 prison_deref(pr, drflags);
3021 return (error);
3022 }
3023 sx_unlock(&allprison_lock);
3024 drflags &= ~(PD_LIST_SLOCKED | PD_LIST_XLOCKED);
3025
3026 /*
3027 * Reparent the newly attached process to this jail.
3028 */
3029 p = td->td_proc;
3030 error = cpuset_setproc_update_set(p, pr->pr_cpuset);
3031 if (error)
3032 goto e_revert_osd;
3033
3034 vn_lock(pr->pr_root, LK_EXCLUSIVE | LK_RETRY);
3035 if ((error = change_dir(pr->pr_root, td)) != 0)
3036 goto e_unlock;
3037 #ifdef MAC
3038 if ((error = mac_vnode_check_chroot(td->td_ucred, pr->pr_root)))
3039 goto e_unlock;
3040 #endif
3041 VOP_UNLOCK(pr->pr_root);
3042 if ((error = pwd_chroot_chdir(td, pr->pr_root)))
3043 goto e_revert_osd;
3044
3045 newcred = crget();
3046 PROC_LOCK(p);
3047 oldcred = crcopysafe(p, newcred);
3048 newcred->cr_prison = pr;
3049 proc_set_cred(p, newcred);
3050 setsugid(p);
3051 #ifdef RACCT
3052 racct_proc_ucred_changed(p, oldcred, newcred);
3053 #endif
3054 #ifdef RCTL
3055 crhold(newcred);
3056 #endif
3057 PROC_UNLOCK(p);
3058 #ifdef RCTL
3059 rctl_proc_ucred_changed(p, newcred);
3060 crfree(newcred);
3061 #endif
3062 prison_proc_relink(oldcred->cr_prison, pr, p);
3063 prison_deref(oldcred->cr_prison, drflags);
3064 crfree(oldcred);
3065 prison_knote(pr, NOTE_JAIL_ATTACH | td->td_proc->p_pid);
3066
3067 /*
3068 * If the prison was killed while changing credentials, die along
3069 * with it.
3070 */
3071 if (!prison_isalive(pr)) {
3072 PROC_LOCK(p);
3073 kern_psignal(p, SIGKILL);
3074 PROC_UNLOCK(p);
3075 }
3076
3077 return (0);
3078
3079 e_unlock:
3080 VOP_UNLOCK(pr->pr_root);
3081 e_revert_osd:
3082 /* Tell modules this thread is still in its old jail after all. */
3083 sx_slock(&allprison_lock);
3084 drflags |= PD_LIST_SLOCKED;
3085 (void)osd_jail_call(td->td_ucred->cr_prison, PR_METHOD_ATTACH, td);
3086 prison_deref(pr, drflags);
3087 return (error);
3088 }
3089
3090 /*
3091 * Returns a locked prison instance, or NULL on failure.
3092 */
3093 struct prison *
prison_find(int prid)3094 prison_find(int prid)
3095 {
3096 struct prison *pr;
3097
3098 sx_assert(&allprison_lock, SX_LOCKED);
3099 TAILQ_FOREACH(pr, &allprison, pr_list) {
3100 if (pr->pr_id < prid)
3101 continue;
3102 if (pr->pr_id > prid)
3103 break;
3104 KASSERT(prison_isvalid(pr), ("Found invalid prison %p", pr));
3105 mtx_lock(&pr->pr_mtx);
3106 return (pr);
3107 }
3108 return (NULL);
3109 }
3110
3111 /*
3112 * Find a prison that is a descendant of mypr. Returns a locked prison or NULL.
3113 */
3114 struct prison *
prison_find_child(struct prison * mypr,int prid)3115 prison_find_child(struct prison *mypr, int prid)
3116 {
3117 struct prison *pr;
3118 int descend;
3119
3120 sx_assert(&allprison_lock, SX_LOCKED);
3121 FOREACH_PRISON_DESCENDANT(mypr, pr, descend) {
3122 if (pr->pr_id == prid) {
3123 KASSERT(prison_isvalid(pr),
3124 ("Found invalid prison %p", pr));
3125 mtx_lock(&pr->pr_mtx);
3126 return (pr);
3127 }
3128 }
3129 return (NULL);
3130 }
3131
3132 /*
3133 * Look for the name relative to mypr. Returns a locked prison or NULL.
3134 */
3135 struct prison *
prison_find_name(struct prison * mypr,const char * name)3136 prison_find_name(struct prison *mypr, const char *name)
3137 {
3138 struct prison *pr, *deadpr;
3139 size_t mylen;
3140 int descend;
3141
3142 sx_assert(&allprison_lock, SX_LOCKED);
3143 mylen = (mypr == &prison0) ? 0 : strlen(mypr->pr_name) + 1;
3144 deadpr = NULL;
3145 FOREACH_PRISON_DESCENDANT(mypr, pr, descend) {
3146 if (!strcmp(pr->pr_name + mylen, name)) {
3147 KASSERT(prison_isvalid(pr),
3148 ("Found invalid prison %p", pr));
3149 if (prison_isalive(pr)) {
3150 mtx_lock(&pr->pr_mtx);
3151 return (pr);
3152 }
3153 deadpr = pr;
3154 }
3155 }
3156 /* There was no valid prison - perhaps there was a dying one. */
3157 if (deadpr != NULL)
3158 mtx_lock(&deadpr->pr_mtx);
3159 return (deadpr);
3160 }
3161
3162 /*
3163 * See if a prison has the specific flag set. The prison should be locked,
3164 * unless checking for flags that are only set at jail creation (such as
3165 * PR_IP4 and PR_IP6), or only the single bit is examined, without regard
3166 * to any other prison data.
3167 */
3168 bool
prison_flag(struct ucred * cred,unsigned flag)3169 prison_flag(struct ucred *cred, unsigned flag)
3170 {
3171
3172 return ((cred->cr_prison->pr_flags & flag) != 0);
3173 }
3174
3175 /*
3176 * See if a prison has the specific allow flag set.
3177 * The prison *should* be locked, or only a single bit is examined, without
3178 * regard to any other prison data.
3179 */
3180 bool
prison_allow(struct ucred * cred,unsigned flag)3181 prison_allow(struct ucred *cred, unsigned flag)
3182 {
3183
3184 return ((cred->cr_prison->pr_allow & flag) != 0);
3185 }
3186
3187 /*
3188 * Hold a prison reference, by incrementing pr_ref. It is generally
3189 * an error to hold a prison that does not already have a reference.
3190 * A prison record will remain valid as long as it has at least one
3191 * reference, and will not be removed as long as either the prison
3192 * mutex or the allprison lock is held (allprison_lock may be shared).
3193 */
3194 void
prison_hold_locked(struct prison * pr)3195 prison_hold_locked(struct prison *pr)
3196 {
3197
3198 /* Locking is no longer required. */
3199 prison_hold(pr);
3200 }
3201
3202 void
prison_hold(struct prison * pr)3203 prison_hold(struct prison *pr)
3204 {
3205 #ifdef INVARIANTS
3206 int was_valid = refcount_acquire_if_not_zero(&pr->pr_ref);
3207
3208 KASSERT(was_valid,
3209 ("Trying to hold dead prison %p (jid=%d).", pr, pr->pr_id));
3210 #else
3211 refcount_acquire(&pr->pr_ref);
3212 #endif
3213 }
3214
3215 /*
3216 * Remove a prison reference. If that was the last reference, the
3217 * prison will be removed (at a later time).
3218 */
3219 void
prison_free_locked(struct prison * pr)3220 prison_free_locked(struct prison *pr)
3221 {
3222
3223 mtx_assert(&pr->pr_mtx, MA_OWNED);
3224 /*
3225 * Locking is no longer required, but unlock because the caller
3226 * expects it.
3227 */
3228 mtx_unlock(&pr->pr_mtx);
3229 prison_free(pr);
3230 }
3231
3232 void
prison_free(struct prison * pr)3233 prison_free(struct prison *pr)
3234 {
3235
3236 KASSERT(refcount_load(&pr->pr_ref) > 0,
3237 ("Trying to free dead prison %p (jid=%d).",
3238 pr, pr->pr_id));
3239 if (!refcount_release_if_not_last(&pr->pr_ref)) {
3240 /*
3241 * Don't remove the last reference in this context,
3242 * in case there are locks held.
3243 */
3244 taskqueue_enqueue(taskqueue_jail_remove, &pr->pr_task);
3245 }
3246 }
3247
3248 static void
prison_free_not_last(struct prison * pr)3249 prison_free_not_last(struct prison *pr)
3250 {
3251 #ifdef INVARIANTS
3252 int lastref;
3253
3254 KASSERT(refcount_load(&pr->pr_ref) > 0,
3255 ("Trying to free dead prison %p (jid=%d).",
3256 pr, pr->pr_id));
3257 lastref = refcount_release(&pr->pr_ref);
3258 KASSERT(!lastref,
3259 ("prison_free_not_last freed last ref on prison %p (jid=%d).",
3260 pr, pr->pr_id));
3261 #else
3262 refcount_release(&pr->pr_ref);
3263 #endif
3264 }
3265
3266 /*
3267 * Hold a prison for user visibility, by incrementing pr_uref.
3268 * It is generally an error to hold a prison that isn't already
3269 * user-visible, except through the jail system calls. It is also
3270 * an error to hold an invalid prison. A prison record will remain
3271 * alive as long as it has at least one user reference, and will not
3272 * be set to the dying state until the prison mutex and allprison_lock
3273 * are both freed.
3274 */
3275 void
prison_proc_hold(struct prison * pr)3276 prison_proc_hold(struct prison *pr)
3277 {
3278 #ifdef INVARIANTS
3279 int was_alive = refcount_acquire_if_not_zero(&pr->pr_uref);
3280
3281 KASSERT(was_alive,
3282 ("Cannot add a process to a non-alive prison (jid=%d)", pr->pr_id));
3283 #else
3284 refcount_acquire(&pr->pr_uref);
3285 #endif
3286 }
3287
3288 /*
3289 * Remove a prison user reference. If it was the last reference, the
3290 * prison will be considered "dying", and may be removed once all of
3291 * its references are dropped.
3292 */
3293 void
prison_proc_free(struct prison * pr)3294 prison_proc_free(struct prison *pr)
3295 {
3296
3297 /*
3298 * Locking is only required when releasing the last reference.
3299 * This allows assurance that a locked prison will remain alive
3300 * until it is unlocked.
3301 */
3302 KASSERT(refcount_load(&pr->pr_uref) > 0,
3303 ("Trying to kill a process in a dead prison (jid=%d)", pr->pr_id));
3304 if (!refcount_release_if_not_last(&pr->pr_uref)) {
3305 /*
3306 * Don't remove the last user reference in this context,
3307 * which is expected to be a process that is not only locked,
3308 * but also half dead. Add a reference so any calls to
3309 * prison_free() won't re-submit the task.
3310 */
3311 prison_hold(pr);
3312 mtx_lock(&pr->pr_mtx);
3313 KASSERT(!(pr->pr_flags & PR_COMPLETE_PROC),
3314 ("Redundant last reference in prison_proc_free (jid=%d)",
3315 pr->pr_id));
3316 pr->pr_flags |= PR_COMPLETE_PROC;
3317 mtx_unlock(&pr->pr_mtx);
3318 taskqueue_enqueue(taskqueue_jail_remove, &pr->pr_task);
3319 }
3320 }
3321
3322 static void
prison_proc_free_not_last(struct prison * pr)3323 prison_proc_free_not_last(struct prison *pr)
3324 {
3325 #ifdef INVARIANTS
3326 int lastref;
3327
3328 KASSERT(refcount_load(&pr->pr_uref) > 0,
3329 ("Trying to free dead prison %p (jid=%d).",
3330 pr, pr->pr_id));
3331 lastref = refcount_release(&pr->pr_uref);
3332 KASSERT(!lastref,
3333 ("prison_proc_free_not_last freed last uref on prison %p (jid=%d).",
3334 pr, pr->pr_id));
3335 #else
3336 refcount_release(&pr->pr_uref);
3337 #endif
3338 }
3339
3340 void
prison_proc_link(struct prison * pr,struct proc * p)3341 prison_proc_link(struct prison *pr, struct proc *p)
3342 {
3343
3344 sx_assert(&allproc_lock, SA_XLOCKED);
3345 LIST_INSERT_HEAD(&pr->pr_proclist, p, p_jaillist);
3346 }
3347
3348 void
prison_proc_unlink(struct prison * pr,struct proc * p)3349 prison_proc_unlink(struct prison *pr, struct proc *p)
3350 {
3351
3352 sx_assert(&allproc_lock, SA_XLOCKED);
3353 LIST_REMOVE(p, p_jaillist);
3354 }
3355
3356 static void
prison_proc_relink(struct prison * opr,struct prison * npr,struct proc * p)3357 prison_proc_relink(struct prison *opr, struct prison *npr, struct proc *p)
3358 {
3359
3360 sx_xlock(&allproc_lock);
3361 prison_proc_unlink(opr, p);
3362 prison_proc_link(npr, p);
3363 sx_xunlock(&allproc_lock);
3364 }
3365
3366 /*
3367 * Complete a call to either prison_free or prison_proc_free.
3368 */
3369 static void
prison_complete(void * context,int pending)3370 prison_complete(void *context, int pending)
3371 {
3372 struct prison *pr = context;
3373 int drflags;
3374
3375 /*
3376 * This could be called to release the last reference, or the last
3377 * user reference (plus the reference held in prison_proc_free).
3378 */
3379 drflags = prison_lock_xlock(pr, PD_DEREF);
3380 if (pr->pr_flags & PR_COMPLETE_PROC) {
3381 pr->pr_flags &= ~PR_COMPLETE_PROC;
3382 drflags |= PD_DEUREF;
3383 }
3384 prison_deref(pr, drflags);
3385 }
3386
3387 static void
prison_kill_processes_cb(struct proc * p,void * arg __unused)3388 prison_kill_processes_cb(struct proc *p, void *arg __unused)
3389 {
3390
3391 kern_psignal(p, SIGKILL);
3392 }
3393
3394 /*
3395 * Note the iteration does not guarantee acting on all processes.
3396 * Most notably there may be fork or jail_attach in progress.
3397 */
3398 void
prison_proc_iterate(struct prison * pr,void (* cb)(struct proc *,void *),void * cbarg)3399 prison_proc_iterate(struct prison *pr, void (*cb)(struct proc *, void *),
3400 void *cbarg)
3401 {
3402 struct prison *ppr;
3403 struct proc *p;
3404
3405 if (atomic_load_int(&pr->pr_childcount) == 0) {
3406 sx_slock(&allproc_lock);
3407 LIST_FOREACH(p, &pr->pr_proclist, p_jaillist) {
3408 if (p->p_state == PRS_NEW)
3409 continue;
3410 PROC_LOCK(p);
3411 cb(p, cbarg);
3412 PROC_UNLOCK(p);
3413 }
3414 sx_sunlock(&allproc_lock);
3415 if (atomic_load_int(&pr->pr_childcount) == 0)
3416 return;
3417 /*
3418 * Some jails popped up during the iteration, fall through to a
3419 * system-wide search.
3420 */
3421 }
3422
3423 sx_slock(&allproc_lock);
3424 FOREACH_PROC_IN_SYSTEM(p) {
3425 PROC_LOCK(p);
3426 if (p->p_state != PRS_NEW && p->p_ucred != NULL) {
3427 for (ppr = p->p_ucred->cr_prison; ppr != NULL;
3428 ppr = ppr->pr_parent) {
3429 if (ppr == pr) {
3430 cb(p, cbarg);
3431 break;
3432 }
3433 }
3434 }
3435 PROC_UNLOCK(p);
3436 }
3437 sx_sunlock(&allproc_lock);
3438 }
3439
3440 /*
3441 * Remove a prison reference and/or user reference (usually).
3442 * This assumes context that allows sleeping (for allprison_lock),
3443 * with no non-sleeping locks held, except perhaps the prison itself.
3444 * If there are no more references, release and delist the prison.
3445 * On completion, the prison lock and the allprison lock are both
3446 * unlocked.
3447 */
3448 static void
prison_deref(struct prison * pr,int flags)3449 prison_deref(struct prison *pr, int flags)
3450 {
3451 struct prisonlist freeprison;
3452 struct prison *killpr, *rpr, *ppr, *tpr;
3453
3454 killpr = NULL;
3455 TAILQ_INIT(&freeprison);
3456 /*
3457 * Release this prison as requested, which may cause its parent
3458 * to be released, and then maybe its grandparent, etc.
3459 */
3460 for (;;) {
3461 if (flags & PD_KILL) {
3462 /* Kill the prison and its descendents. */
3463 KASSERT(pr != &prison0,
3464 ("prison_deref trying to kill prison0"));
3465 if (!prison_isalive(pr)) {
3466 /* Silently ignore already-dying prisons. */
3467 flags &= ~PD_KILL;
3468 } else {
3469 if (!(flags & PD_DEREF)) {
3470 prison_hold(pr);
3471 flags |= PD_DEREF;
3472 }
3473 flags = prison_lock_xlock(pr, flags);
3474 prison_deref_kill(pr, &freeprison);
3475 }
3476 }
3477 if (flags & PD_DEUREF) {
3478 /* Drop a user reference. */
3479 KASSERT(refcount_load(&pr->pr_uref) > 0,
3480 ("prison_deref PD_DEUREF on a dead prison (jid=%d)",
3481 pr->pr_id));
3482 if (!refcount_release_if_not_last(&pr->pr_uref)) {
3483 if (!(flags & PD_DEREF)) {
3484 prison_hold(pr);
3485 flags |= PD_DEREF;
3486 }
3487 flags = prison_lock_xlock(pr, flags);
3488 if (refcount_release(&pr->pr_uref) &&
3489 pr->pr_state == PRISON_STATE_ALIVE) {
3490 /*
3491 * When the last user references goes,
3492 * this becomes a dying prison.
3493 */
3494 KASSERT(
3495 refcount_load(&prison0.pr_uref) > 0,
3496 ("prison0 pr_uref=0"));
3497 pr->pr_state = PRISON_STATE_DYING;
3498 prison_cleanup_locked(pr);
3499 mtx_unlock(&pr->pr_mtx);
3500 flags &= ~PD_LOCKED;
3501 prison_cleanup_unlocked(pr);
3502 }
3503 }
3504 }
3505 if (flags & PD_KILL) {
3506 /*
3507 * Any remaining user references are probably processes
3508 * that need to be killed, either in this prison or its
3509 * descendants.
3510 */
3511 if (refcount_load(&pr->pr_uref) > 0)
3512 killpr = pr;
3513 /* Make sure the parent prison doesn't get killed. */
3514 flags &= ~PD_KILL;
3515 }
3516 if (flags & PD_DEREF) {
3517 /* Drop a reference. */
3518 KASSERT(refcount_load(&pr->pr_ref) > 0,
3519 ("prison_deref PD_DEREF on a dead prison (jid=%d)",
3520 pr->pr_id));
3521 if (!refcount_release_if_not_last(&pr->pr_ref)) {
3522 flags = prison_lock_xlock(pr, flags);
3523 if (refcount_release(&pr->pr_ref)) {
3524 /*
3525 * When the last reference goes,
3526 * unlink the prison and set it aside.
3527 */
3528 KASSERT(
3529 refcount_load(&pr->pr_uref) == 0,
3530 ("prison_deref: last ref, "
3531 "but still has %d urefs (jid=%d)",
3532 pr->pr_uref, pr->pr_id));
3533 KASSERT(
3534 refcount_load(&prison0.pr_ref) != 0,
3535 ("prison0 pr_ref=0"));
3536 pr->pr_state = PRISON_STATE_INVALID;
3537 TAILQ_REMOVE(&allprison, pr, pr_list);
3538 LIST_REMOVE(pr, pr_sibling);
3539 TAILQ_INSERT_TAIL(&freeprison, pr,
3540 pr_list);
3541 for (ppr = pr->pr_parent;
3542 ppr != NULL;
3543 ppr = ppr->pr_parent)
3544 ppr->pr_childcount--;
3545 /*
3546 * Removing a prison frees references
3547 * from its parent.
3548 */
3549 ppr = pr->pr_parent;
3550 pr->pr_parent = NULL;
3551 mtx_unlock(&pr->pr_mtx);
3552
3553 pr = ppr;
3554 flags &= ~PD_LOCKED;
3555 flags |= PD_DEREF | PD_DEUREF;
3556 continue;
3557 }
3558 }
3559 }
3560 break;
3561 }
3562
3563 /* Release all the prison locks. */
3564 if (flags & PD_LOCKED)
3565 mtx_unlock(&pr->pr_mtx);
3566 if (flags & PD_LIST_SLOCKED)
3567 sx_sunlock(&allprison_lock);
3568 else if (flags & PD_LIST_XLOCKED)
3569 sx_xunlock(&allprison_lock);
3570
3571 /* Kill any processes attached to a killed prison. */
3572 if (killpr != NULL)
3573 prison_proc_iterate(killpr, prison_kill_processes_cb, NULL);
3574
3575 /*
3576 * Finish removing any unreferenced prisons, which couldn't happen
3577 * while allprison_lock was held (to avoid a LOR on vrele).
3578 */
3579 TAILQ_FOREACH_SAFE(rpr, &freeprison, pr_list, tpr) {
3580 #ifdef VIMAGE
3581 if (rpr->pr_flags & PR_VNET)
3582 vnet_destroy(rpr->pr_vnet);
3583 #endif
3584 if (rpr->pr_root != NULL)
3585 vrele(rpr->pr_root);
3586 mtx_destroy(&rpr->pr_mtx);
3587 #ifdef INET
3588 prison_ip_free(rpr->pr_addrs[PR_INET]);
3589 #endif
3590 #ifdef INET6
3591 prison_ip_free(rpr->pr_addrs[PR_INET6]);
3592 #endif
3593 if (rpr->pr_cpuset != NULL)
3594 cpuset_rel(rpr->pr_cpuset);
3595 osd_jail_exit(rpr);
3596 #ifdef RACCT
3597 if (racct_enable)
3598 prison_racct_detach(rpr);
3599 #endif
3600 TAILQ_REMOVE(&freeprison, rpr, pr_list);
3601 free(rpr, M_PRISON);
3602 }
3603 }
3604
3605 /*
3606 * Kill the prison and its descendants. Mark them as dying, clear the
3607 * persist flag, and call module remove methods.
3608 */
3609 static void
prison_deref_kill(struct prison * pr,struct prisonlist * freeprison)3610 prison_deref_kill(struct prison *pr, struct prisonlist *freeprison)
3611 {
3612 struct prison *cpr, *ppr, *rpr;
3613 bool descend;
3614
3615 /*
3616 * Unlike the descendants, the target prison can be killed
3617 * even if it is currently dying. This is useful for failed
3618 * creation in jail_set(2).
3619 */
3620 KASSERT(refcount_load(&pr->pr_ref) > 0,
3621 ("Trying to kill dead prison %p (jid=%d).",
3622 pr, pr->pr_id));
3623 refcount_acquire(&pr->pr_uref);
3624 pr->pr_state = PRISON_STATE_DYING;
3625 mtx_unlock(&pr->pr_mtx);
3626
3627 rpr = NULL;
3628 FOREACH_PRISON_DESCENDANT_PRE_POST(pr, cpr, descend) {
3629 if (descend) {
3630 if (!prison_isalive(cpr)) {
3631 descend = false;
3632 continue;
3633 }
3634 prison_hold(cpr);
3635 prison_proc_hold(cpr);
3636 mtx_lock(&cpr->pr_mtx);
3637 cpr->pr_state = PRISON_STATE_DYING;
3638 cpr->pr_flags |= PR_REMOVE;
3639 mtx_unlock(&cpr->pr_mtx);
3640 continue;
3641 }
3642 if (!(cpr->pr_flags & PR_REMOVE))
3643 continue;
3644 prison_cleanup_unlocked(cpr);
3645 mtx_lock(&cpr->pr_mtx);
3646 prison_cleanup_locked(cpr);
3647 cpr->pr_flags &= ~PR_REMOVE;
3648 if (cpr->pr_flags & PR_PERSIST) {
3649 cpr->pr_flags &= ~PR_PERSIST;
3650 prison_proc_free_not_last(cpr);
3651 prison_free_not_last(cpr);
3652 }
3653 (void)refcount_release(&cpr->pr_uref);
3654 if (refcount_release(&cpr->pr_ref)) {
3655 /*
3656 * When the last reference goes, unlink the prison
3657 * and set it aside for prison_deref() to handle.
3658 * Delay unlinking the sibling list to keep the loop
3659 * safe.
3660 */
3661 if (rpr != NULL)
3662 LIST_REMOVE(rpr, pr_sibling);
3663 rpr = cpr;
3664 rpr->pr_state = PRISON_STATE_INVALID;
3665 TAILQ_REMOVE(&allprison, rpr, pr_list);
3666 TAILQ_INSERT_TAIL(freeprison, rpr, pr_list);
3667 /*
3668 * Removing a prison frees references from its parent.
3669 */
3670 ppr = rpr->pr_parent;
3671 prison_proc_free_not_last(ppr);
3672 prison_free_not_last(ppr);
3673 for (; ppr != NULL; ppr = ppr->pr_parent)
3674 ppr->pr_childcount--;
3675 }
3676 mtx_unlock(&cpr->pr_mtx);
3677 }
3678 if (rpr != NULL)
3679 LIST_REMOVE(rpr, pr_sibling);
3680
3681 prison_cleanup_unlocked(pr);
3682 mtx_lock(&pr->pr_mtx);
3683 prison_cleanup_locked(pr);
3684 if (pr->pr_flags & PR_PERSIST) {
3685 pr->pr_flags &= ~PR_PERSIST;
3686 prison_proc_free_not_last(pr);
3687 prison_free_not_last(pr);
3688 }
3689 (void)refcount_release(&pr->pr_uref);
3690 }
3691
3692 /*
3693 * Given the current locking state in the flags, make sure allprison_lock
3694 * is held exclusive, and the prison is locked. Return flags indicating
3695 * the new state.
3696 */
3697 static int
prison_lock_xlock(struct prison * pr,int flags)3698 prison_lock_xlock(struct prison *pr, int flags)
3699 {
3700
3701 if (!(flags & PD_LIST_XLOCKED)) {
3702 /*
3703 * Get allprison_lock, which may be an upgrade,
3704 * and may require unlocking the prison.
3705 */
3706 if (flags & PD_LOCKED) {
3707 mtx_unlock(&pr->pr_mtx);
3708 flags &= ~PD_LOCKED;
3709 }
3710 if (flags & PD_LIST_SLOCKED) {
3711 if (!sx_try_upgrade(&allprison_lock)) {
3712 sx_sunlock(&allprison_lock);
3713 sx_xlock(&allprison_lock);
3714 }
3715 flags &= ~PD_LIST_SLOCKED;
3716 } else
3717 sx_xlock(&allprison_lock);
3718 flags |= PD_LIST_XLOCKED;
3719 }
3720 if (!(flags & PD_LOCKED)) {
3721 /* Lock the prison mutex. */
3722 mtx_lock(&pr->pr_mtx);
3723 flags |= PD_LOCKED;
3724 }
3725 return flags;
3726 }
3727
3728 /*
3729 * Release a prison's resources when it starts dying (when the last user
3730 * reference is dropped, or when it is killed). Two functions are called,
3731 * for work that requires a locked prison or an unlocked one.
3732 */
3733 static void
prison_cleanup_locked(struct prison * pr)3734 prison_cleanup_locked(struct prison *pr)
3735 {
3736 sx_assert(&allprison_lock, SA_XLOCKED);
3737 mtx_assert(&pr->pr_mtx, MA_OWNED);
3738 prison_knote(pr, NOTE_JAIL_REMOVE);
3739 knlist_detach(pr->pr_klist);
3740 jaildesc_prison_cleanup(pr);
3741 pr->pr_klist = NULL;
3742 }
3743
3744 static void
prison_cleanup_unlocked(struct prison * pr)3745 prison_cleanup_unlocked(struct prison *pr)
3746 {
3747 sx_assert(&allprison_lock, SA_XLOCKED);
3748 mtx_assert(&pr->pr_mtx, MA_NOTOWNED);
3749 vfs_exjail_delete(pr);
3750 shm_remove_prison(pr);
3751 (void)osd_jail_call(pr, PR_METHOD_REMOVE, NULL);
3752 }
3753
3754 /*
3755 * Set or clear a permission bit in the pr_allow field, passing restrictions
3756 * (cleared permission) down to child jails.
3757 */
3758 void
prison_set_allow(struct ucred * cred,unsigned flag,int enable)3759 prison_set_allow(struct ucred *cred, unsigned flag, int enable)
3760 {
3761 struct prison *pr;
3762
3763 pr = cred->cr_prison;
3764 sx_slock(&allprison_lock);
3765 mtx_lock(&pr->pr_mtx);
3766 prison_set_allow_locked(pr, flag, enable);
3767 mtx_unlock(&pr->pr_mtx);
3768 sx_sunlock(&allprison_lock);
3769 }
3770
3771 static void
prison_set_allow_locked(struct prison * pr,unsigned flag,int enable)3772 prison_set_allow_locked(struct prison *pr, unsigned flag, int enable)
3773 {
3774 struct prison *cpr;
3775 int descend;
3776
3777 if (enable != 0)
3778 pr->pr_allow |= flag;
3779 else {
3780 pr->pr_allow &= ~flag;
3781 FOREACH_PRISON_DESCENDANT_LOCKED(pr, cpr, descend)
3782 cpr->pr_allow &= ~flag;
3783 }
3784 }
3785
3786 /*
3787 * Check if a jail supports the given address family.
3788 *
3789 * Returns 0 if not jailed or the address family is supported, EAFNOSUPPORT
3790 * if not.
3791 */
3792 int
prison_check_af(struct ucred * cred,int af)3793 prison_check_af(struct ucred *cred, int af)
3794 {
3795 struct prison *pr;
3796 int error;
3797
3798 KASSERT(cred != NULL, ("%s: cred is NULL", __func__));
3799
3800 pr = cred->cr_prison;
3801 #ifdef VIMAGE
3802 /* Prisons with their own network stack are not limited. */
3803 if (prison_owns_vnet(pr))
3804 return (0);
3805 #endif
3806
3807 error = 0;
3808 switch (af)
3809 {
3810 #ifdef INET
3811 case AF_INET:
3812 if (pr->pr_flags & PR_IP4)
3813 {
3814 mtx_lock(&pr->pr_mtx);
3815 if ((pr->pr_flags & PR_IP4) &&
3816 pr->pr_addrs[PR_INET] == NULL)
3817 error = EAFNOSUPPORT;
3818 mtx_unlock(&pr->pr_mtx);
3819 }
3820 break;
3821 #endif
3822 #ifdef INET6
3823 case AF_INET6:
3824 if (pr->pr_flags & PR_IP6)
3825 {
3826 mtx_lock(&pr->pr_mtx);
3827 if ((pr->pr_flags & PR_IP6) &&
3828 pr->pr_addrs[PR_INET6] == NULL)
3829 error = EAFNOSUPPORT;
3830 mtx_unlock(&pr->pr_mtx);
3831 }
3832 break;
3833 #endif
3834 case AF_LOCAL:
3835 case AF_ROUTE:
3836 case AF_NETLINK:
3837 break;
3838 default:
3839 if (!(pr->pr_allow & PR_ALLOW_SOCKET_AF))
3840 error = EAFNOSUPPORT;
3841 }
3842 return (error);
3843 }
3844
3845 /*
3846 * Check if given address belongs to the jail referenced by cred (wrapper to
3847 * prison_check_ip[46]).
3848 *
3849 * Returns 0 if jail doesn't restrict the address family or if address belongs
3850 * to jail, EADDRNOTAVAIL if the address doesn't belong, or EAFNOSUPPORT if
3851 * the jail doesn't allow the address family. IPv4 Address passed in in NBO.
3852 */
3853 int
prison_if(struct ucred * cred,const struct sockaddr * sa)3854 prison_if(struct ucred *cred, const struct sockaddr *sa)
3855 {
3856 #ifdef INET
3857 const struct sockaddr_in *sai;
3858 #endif
3859 #ifdef INET6
3860 const struct sockaddr_in6 *sai6;
3861 #endif
3862 int error;
3863
3864 KASSERT(cred != NULL, ("%s: cred is NULL", __func__));
3865 KASSERT(sa != NULL, ("%s: sa is NULL", __func__));
3866
3867 #ifdef VIMAGE
3868 if (prison_owns_vnet(cred->cr_prison))
3869 return (0);
3870 #endif
3871
3872 error = 0;
3873 switch (sa->sa_family)
3874 {
3875 #ifdef INET
3876 case AF_INET:
3877 sai = (const struct sockaddr_in *)sa;
3878 error = prison_check_ip4(cred, &sai->sin_addr);
3879 break;
3880 #endif
3881 #ifdef INET6
3882 case AF_INET6:
3883 sai6 = (const struct sockaddr_in6 *)sa;
3884 error = prison_check_ip6(cred, &sai6->sin6_addr);
3885 break;
3886 #endif
3887 default:
3888 if (!(cred->cr_prison->pr_allow & PR_ALLOW_SOCKET_AF))
3889 error = EAFNOSUPPORT;
3890 }
3891 return (error);
3892 }
3893
3894 /*
3895 * Return 0 if jails permit p1 to frob p2, otherwise ESRCH.
3896 */
3897 int
prison_check(struct ucred * cred1,struct ucred * cred2)3898 prison_check(struct ucred *cred1, struct ucred *cred2)
3899 {
3900
3901 return ((cred1->cr_prison == cred2->cr_prison ||
3902 prison_ischild(cred1->cr_prison, cred2->cr_prison)) ? 0 : ESRCH);
3903 }
3904
3905 /*
3906 * For mountd/nfsd to run within a prison, it must be:
3907 * - A vnet prison.
3908 * - PR_ALLOW_NFSD must be set on it.
3909 * - The root directory (pr_root) of the prison must be
3910 * a file system mount point, so the mountd can hang
3911 * export information on it.
3912 * - The prison's enforce_statfs cannot be 0, so that
3913 * mountd(8) can do exports.
3914 */
3915 bool
prison_check_nfsd(struct ucred * cred)3916 prison_check_nfsd(struct ucred *cred)
3917 {
3918
3919 if (jailed_without_vnet(cred))
3920 return (false);
3921 if (!prison_allow(cred, PR_ALLOW_NFSD))
3922 return (false);
3923 if ((cred->cr_prison->pr_root->v_vflag & VV_ROOT) == 0)
3924 return (false);
3925 if (cred->cr_prison->pr_enforce_statfs == 0)
3926 return (false);
3927 return (true);
3928 }
3929
3930 /*
3931 * Return true if p2 is a child of p1, otherwise false.
3932 */
3933 bool
prison_ischild(struct prison * pr1,struct prison * pr2)3934 prison_ischild(struct prison *pr1, struct prison *pr2)
3935 {
3936
3937 for (pr2 = pr2->pr_parent; pr2 != NULL; pr2 = pr2->pr_parent)
3938 if (pr1 == pr2)
3939 return (true);
3940 return (false);
3941 }
3942
3943 /*
3944 * Return true if the prison is currently alive. A prison is alive if it
3945 * holds user references and it isn't being removed.
3946 */
3947 bool
prison_isalive(const struct prison * pr)3948 prison_isalive(const struct prison *pr)
3949 {
3950
3951 if (__predict_false(pr->pr_state != PRISON_STATE_ALIVE))
3952 return (false);
3953 return (true);
3954 }
3955
3956 /*
3957 * Return true if the prison is currently valid. A prison is valid if it has
3958 * been fully created, and is not being destroyed. Note that dying prisons
3959 * are still considered valid. Invalid prisons won't be found under normal
3960 * circumstances, as they're only put in that state by functions that have
3961 * an exclusive hold on allprison_lock.
3962 */
3963 bool
prison_isvalid(struct prison * pr)3964 prison_isvalid(struct prison *pr)
3965 {
3966
3967 if (__predict_false(pr->pr_state == PRISON_STATE_INVALID))
3968 return (false);
3969 if (__predict_false(refcount_load(&pr->pr_ref) == 0))
3970 return (false);
3971 return (true);
3972 }
3973
3974 /*
3975 * Return true if the passed credential is in a jail and that jail does not
3976 * have its own virtual network stack, otherwise false.
3977 */
3978 bool
jailed_without_vnet(struct ucred * cred)3979 jailed_without_vnet(struct ucred *cred)
3980 {
3981
3982 if (!jailed(cred))
3983 return (false);
3984 #ifdef VIMAGE
3985 if (prison_owns_vnet(cred->cr_prison))
3986 return (false);
3987 #endif
3988
3989 return (true);
3990 }
3991
3992 /*
3993 * Return the correct hostname (domainname, et al) for the passed credential.
3994 */
3995 void
getcredhostname(struct ucred * cred,char * buf,size_t size)3996 getcredhostname(struct ucred *cred, char *buf, size_t size)
3997 {
3998 struct prison *pr;
3999
4000 /*
4001 * A NULL credential can be used to shortcut to the physical
4002 * system's hostname.
4003 */
4004 pr = (cred != NULL) ? cred->cr_prison : &prison0;
4005 mtx_lock(&pr->pr_mtx);
4006 strlcpy(buf, pr->pr_hostname, size);
4007 mtx_unlock(&pr->pr_mtx);
4008 }
4009
4010 void
getcreddomainname(struct ucred * cred,char * buf,size_t size)4011 getcreddomainname(struct ucred *cred, char *buf, size_t size)
4012 {
4013
4014 mtx_lock(&cred->cr_prison->pr_mtx);
4015 strlcpy(buf, cred->cr_prison->pr_domainname, size);
4016 mtx_unlock(&cred->cr_prison->pr_mtx);
4017 }
4018
4019 void
getcredhostuuid(struct ucred * cred,char * buf,size_t size)4020 getcredhostuuid(struct ucred *cred, char *buf, size_t size)
4021 {
4022
4023 mtx_lock(&cred->cr_prison->pr_mtx);
4024 strlcpy(buf, cred->cr_prison->pr_hostuuid, size);
4025 mtx_unlock(&cred->cr_prison->pr_mtx);
4026 }
4027
4028 void
getcredhostid(struct ucred * cred,unsigned long * hostid)4029 getcredhostid(struct ucred *cred, unsigned long *hostid)
4030 {
4031
4032 mtx_lock(&cred->cr_prison->pr_mtx);
4033 *hostid = cred->cr_prison->pr_hostid;
4034 mtx_unlock(&cred->cr_prison->pr_mtx);
4035 }
4036
4037 void
getjailname(struct ucred * cred,char * name,size_t len)4038 getjailname(struct ucred *cred, char *name, size_t len)
4039 {
4040
4041 mtx_lock(&cred->cr_prison->pr_mtx);
4042 strlcpy(name, cred->cr_prison->pr_name, len);
4043 mtx_unlock(&cred->cr_prison->pr_mtx);
4044 }
4045
4046 #ifdef VIMAGE
4047 /*
4048 * Determine whether the prison owns its VNET.
4049 */
4050 bool
prison_owns_vnet(struct prison * pr)4051 prison_owns_vnet(struct prison *pr)
4052 {
4053
4054 /*
4055 * vnets cannot be added/removed after jail creation,
4056 * so no need to lock here.
4057 */
4058 return ((pr->pr_flags & PR_VNET) != 0);
4059 }
4060 #endif
4061
4062 /*
4063 * Determine whether the subject represented by cred can "see"
4064 * status of a mount point.
4065 * Returns: 0 for permitted, ENOENT otherwise.
4066 * XXX: This function should be called cr_canseemount() and should be
4067 * placed in kern_prot.c.
4068 */
4069 int
prison_canseemount(struct ucred * cred,struct mount * mp)4070 prison_canseemount(struct ucred *cred, struct mount *mp)
4071 {
4072 struct prison *pr;
4073 struct statfs *sp;
4074 size_t len;
4075
4076 pr = cred->cr_prison;
4077 if (pr->pr_enforce_statfs == 0)
4078 return (0);
4079 if (pr->pr_root->v_mount == mp)
4080 return (0);
4081 if (pr->pr_enforce_statfs == 2)
4082 return (ENOENT);
4083 /*
4084 * If jail's chroot directory is set to "/" we should be able to see
4085 * all mount-points from inside a jail.
4086 * This is ugly check, but this is the only situation when jail's
4087 * directory ends with '/'.
4088 */
4089 if (strcmp(pr->pr_path, "/") == 0)
4090 return (0);
4091 len = strlen(pr->pr_path);
4092 sp = &mp->mnt_stat;
4093 if (strncmp(pr->pr_path, sp->f_mntonname, len) != 0)
4094 return (ENOENT);
4095 /*
4096 * Be sure that we don't have situation where jail's root directory
4097 * is "/some/path" and mount point is "/some/pathpath".
4098 */
4099 if (sp->f_mntonname[len] != '\0' && sp->f_mntonname[len] != '/')
4100 return (ENOENT);
4101 return (0);
4102 }
4103
4104 void
prison_enforce_statfs(struct ucred * cred,struct mount * mp,struct statfs * sp)4105 prison_enforce_statfs(struct ucred *cred, struct mount *mp, struct statfs *sp)
4106 {
4107 char jpath[MAXPATHLEN];
4108 struct prison *pr;
4109 size_t len;
4110
4111 pr = cred->cr_prison;
4112 if (pr->pr_enforce_statfs == 0)
4113 return;
4114 if (prison_canseemount(cred, mp) != 0) {
4115 bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
4116 strlcpy(sp->f_mntonname, "[restricted]",
4117 sizeof(sp->f_mntonname));
4118 return;
4119 }
4120 if (pr->pr_root->v_mount == mp) {
4121 /*
4122 * Clear current buffer data, so we are sure nothing from
4123 * the valid path left there.
4124 */
4125 bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
4126 *sp->f_mntonname = '/';
4127 return;
4128 }
4129 /*
4130 * If jail's chroot directory is set to "/" we should be able to see
4131 * all mount-points from inside a jail.
4132 */
4133 if (strcmp(pr->pr_path, "/") == 0)
4134 return;
4135 len = strlen(pr->pr_path);
4136 strlcpy(jpath, sp->f_mntonname + len, sizeof(jpath));
4137 /*
4138 * Clear current buffer data, so we are sure nothing from
4139 * the valid path left there.
4140 */
4141 bzero(sp->f_mntonname, sizeof(sp->f_mntonname));
4142 if (*jpath == '\0') {
4143 /* Should never happen. */
4144 *sp->f_mntonname = '/';
4145 } else {
4146 strlcpy(sp->f_mntonname, jpath, sizeof(sp->f_mntonname));
4147 }
4148 }
4149
4150 /*
4151 * Check with permission for a specific privilege is granted within jail. We
4152 * have a specific list of accepted privileges; the rest are denied.
4153 */
4154 int
prison_priv_check(struct ucred * cred,int priv)4155 prison_priv_check(struct ucred *cred, int priv)
4156 {
4157 struct prison *pr;
4158 int error;
4159
4160 /*
4161 * Some policies have custom handlers. This routine should not be
4162 * called for them. See priv_check_cred().
4163 */
4164 switch (priv) {
4165 case PRIV_VFS_LOOKUP:
4166 case PRIV_VFS_GENERATION:
4167 KASSERT(0, ("prison_priv_check instead of a custom handler "
4168 "called for %d\n", priv));
4169 }
4170
4171 if (!jailed(cred))
4172 return (0);
4173
4174 #ifdef VIMAGE
4175 /*
4176 * Privileges specific to prisons with a virtual network stack.
4177 * There might be a duplicate entry here in case the privilege
4178 * is only granted conditionally in the legacy jail case.
4179 */
4180 switch (priv) {
4181 /*
4182 * NFS-specific privileges.
4183 */
4184 case PRIV_NFS_DAEMON:
4185 case PRIV_VFS_GETFH:
4186 case PRIV_VFS_MOUNT_EXPORTED:
4187 if (!prison_check_nfsd(cred))
4188 return (EPERM);
4189 #ifdef notyet
4190 case PRIV_NFS_LOCKD:
4191 #endif
4192 /*
4193 * Network stack privileges.
4194 */
4195 case PRIV_NET_BRIDGE:
4196 case PRIV_NET_GRE:
4197 case PRIV_NET_BPF:
4198 case PRIV_NET_RAW: /* Dup, cond. in legacy jail case. */
4199 case PRIV_NET_ROUTE:
4200 case PRIV_NET_TAP:
4201 case PRIV_NET_SETIFMTU:
4202 case PRIV_NET_SETIFFLAGS:
4203 case PRIV_NET_SETIFCAP:
4204 case PRIV_NET_SETIFDESCR:
4205 case PRIV_NET_SETIFNAME :
4206 case PRIV_NET_SETIFMETRIC:
4207 case PRIV_NET_SETIFPHYS:
4208 case PRIV_NET_SETIFMAC:
4209 case PRIV_NET_SETLANPCP:
4210 case PRIV_NET_ADDMULTI:
4211 case PRIV_NET_DELMULTI:
4212 case PRIV_NET_HWIOCTL:
4213 case PRIV_NET_SETLLADDR:
4214 case PRIV_NET_ADDIFGROUP:
4215 case PRIV_NET_DELIFGROUP:
4216 case PRIV_NET_IFCREATE:
4217 case PRIV_NET_IFDESTROY:
4218 case PRIV_NET_ADDIFADDR:
4219 case PRIV_NET_DELIFADDR:
4220 case PRIV_NET_LAGG:
4221 case PRIV_NET_GIF:
4222 case PRIV_NET_SETIFVNET:
4223 case PRIV_NET_SETIFFIB:
4224 case PRIV_NET_OVPN:
4225 case PRIV_NET_ME:
4226 case PRIV_NET_WG:
4227
4228 /*
4229 * 802.11-related privileges.
4230 */
4231 case PRIV_NET80211_VAP_GETKEY:
4232 case PRIV_NET80211_VAP_MANAGE:
4233
4234 #ifdef notyet
4235 /*
4236 * ATM privileges.
4237 */
4238 case PRIV_NETATM_CFG:
4239 case PRIV_NETATM_ADD:
4240 case PRIV_NETATM_DEL:
4241 case PRIV_NETATM_SET:
4242
4243 /*
4244 * Bluetooth privileges.
4245 */
4246 case PRIV_NETBLUETOOTH_RAW:
4247 #endif
4248
4249 /*
4250 * Netgraph and netgraph module privileges.
4251 */
4252 case PRIV_NETGRAPH_CONTROL:
4253 #ifdef notyet
4254 case PRIV_NETGRAPH_TTY:
4255 #endif
4256
4257 /*
4258 * IPv4 and IPv6 privileges.
4259 */
4260 case PRIV_NETINET_IPFW:
4261 case PRIV_NETINET_DIVERT:
4262 case PRIV_NETINET_PF:
4263 case PRIV_NETINET_DUMMYNET:
4264 case PRIV_NETINET_CARP:
4265 case PRIV_NETINET_MROUTE:
4266 case PRIV_NETINET_RAW:
4267 case PRIV_NETINET_ADDRCTRL6:
4268 case PRIV_NETINET_ND6:
4269 case PRIV_NETINET_SCOPE6:
4270 case PRIV_NETINET_ALIFETIME6:
4271 case PRIV_NETINET_IPSEC:
4272 case PRIV_NETINET_BINDANY:
4273
4274 #ifdef notyet
4275 /*
4276 * NCP privileges.
4277 */
4278 case PRIV_NETNCP:
4279
4280 /*
4281 * SMB privileges.
4282 */
4283 case PRIV_NETSMB:
4284 #endif
4285
4286 /*
4287 * No default: or deny here.
4288 * In case of no permit fall through to next switch().
4289 */
4290 if (cred->cr_prison->pr_flags & PR_VNET)
4291 return (0);
4292 }
4293 #endif /* VIMAGE */
4294
4295 switch (priv) {
4296 /*
4297 * Allow ktrace privileges for root in jail.
4298 */
4299 case PRIV_KTRACE:
4300
4301 /*
4302 * Allow jailed processes to configure audit identity and
4303 * submit audit records (login, etc). In the future we may
4304 * want to further refine the relationship between audit and
4305 * jail.
4306 */
4307 case PRIV_AUDIT_GETAUDIT:
4308 case PRIV_AUDIT_SETAUDIT:
4309 if (cred->cr_prison->pr_allow & PR_ALLOW_SETAUDIT)
4310 return (0);
4311 else
4312 return (EPERM);
4313 #if 0
4314 case PRIV_AUDIT_SUBMIT:
4315 #endif
4316
4317 /*
4318 * Allow jailed processes to manipulate process UNIX
4319 * credentials in any way they see fit.
4320 */
4321 case PRIV_CRED_SETCRED:
4322 case PRIV_CRED_SETUID:
4323 case PRIV_CRED_SETEUID:
4324 case PRIV_CRED_SETGID:
4325 case PRIV_CRED_SETEGID:
4326 case PRIV_CRED_SETGROUPS:
4327 case PRIV_CRED_SETREUID:
4328 case PRIV_CRED_SETREGID:
4329 case PRIV_CRED_SETRESUID:
4330 case PRIV_CRED_SETRESGID:
4331
4332 /*
4333 * Jail implements visibility constraints already, so allow
4334 * jailed root to override uid/gid-based constraints.
4335 */
4336 case PRIV_SEEOTHERGIDS:
4337 case PRIV_SEEOTHERUIDS:
4338 case PRIV_SEEJAILPROC:
4339
4340 /*
4341 * Jail implements inter-process debugging limits already, so
4342 * allow jailed root various debugging privileges.
4343 */
4344 case PRIV_DEBUG_DIFFCRED:
4345 case PRIV_DEBUG_SUGID:
4346 case PRIV_DEBUG_UNPRIV:
4347 case PRIV_DEBUG_DIFFJAIL:
4348
4349 /*
4350 * Allow jail to set various resource limits and login
4351 * properties, and for now, exceed process resource limits.
4352 */
4353 case PRIV_PROC_LIMIT:
4354 case PRIV_PROC_SETLOGIN:
4355 case PRIV_PROC_SETRLIMIT:
4356
4357 /*
4358 * Debuggers should work in jails.
4359 */
4360 case PRIV_PROC_MEM_WRITE:
4361
4362 /*
4363 * System V and POSIX IPC privileges are granted in jail.
4364 */
4365 case PRIV_IPC_READ:
4366 case PRIV_IPC_WRITE:
4367 case PRIV_IPC_ADMIN:
4368 case PRIV_IPC_MSGSIZE:
4369 case PRIV_MQ_ADMIN:
4370
4371 /*
4372 * Jail operations within a jail work on child jails.
4373 */
4374 case PRIV_JAIL_ATTACH:
4375 case PRIV_JAIL_SET:
4376 case PRIV_JAIL_REMOVE:
4377
4378 /*
4379 * Jail implements its own inter-process limits, so allow
4380 * root processes in jail to change scheduling on other
4381 * processes in the same jail. Likewise for signalling.
4382 */
4383 case PRIV_SCHED_DIFFCRED:
4384 case PRIV_SCHED_CPUSET:
4385 case PRIV_SCHED_DIFFJAIL:
4386 case PRIV_SIGNAL_DIFFCRED:
4387 case PRIV_SIGNAL_SUGID:
4388 case PRIV_SIGNAL_DIFFJAIL:
4389
4390 /*
4391 * Allow jailed processes to write to sysctls marked as jail
4392 * writable.
4393 */
4394 case PRIV_SYSCTL_WRITEJAIL:
4395
4396 /*
4397 * Allow root in jail to manage a variety of quota
4398 * properties. These should likely be conditional on a
4399 * configuration option.
4400 */
4401 case PRIV_VFS_GETQUOTA:
4402 case PRIV_VFS_SETQUOTA:
4403
4404 /*
4405 * Since Jail relies on chroot() to implement file system
4406 * protections, grant many VFS privileges to root in jail.
4407 * Be careful to exclude mount-related and NFS-related
4408 * privileges.
4409 */
4410 case PRIV_VFS_READ:
4411 case PRIV_VFS_WRITE:
4412 case PRIV_VFS_ADMIN:
4413 case PRIV_VFS_EXEC:
4414 case PRIV_VFS_BLOCKRESERVE: /* XXXRW: Slightly surprising. */
4415 case PRIV_VFS_CHFLAGS_DEV:
4416 case PRIV_VFS_CHOWN:
4417 case PRIV_VFS_CHROOT:
4418 case PRIV_VFS_RETAINSUGID:
4419 case PRIV_VFS_FCHROOT:
4420 case PRIV_VFS_LINK:
4421 case PRIV_VFS_SETGID:
4422 case PRIV_VFS_STAT:
4423 case PRIV_VFS_STICKYFILE:
4424
4425 /*
4426 * As in the non-jail case, non-root users are expected to be
4427 * able to read kernel/physical memory (provided /dev/[k]mem
4428 * exists in the jail and they have permission to access it).
4429 */
4430 case PRIV_KMEM_READ:
4431 return (0);
4432
4433 /*
4434 * Depending on the global setting, allow privilege of
4435 * setting system flags.
4436 */
4437 case PRIV_VFS_SYSFLAGS:
4438 if (cred->cr_prison->pr_allow & PR_ALLOW_CHFLAGS)
4439 return (0);
4440 else
4441 return (EPERM);
4442
4443 /*
4444 * Depending on the global setting, allow privilege of
4445 * mounting/unmounting file systems.
4446 */
4447 case PRIV_VFS_MOUNT:
4448 case PRIV_VFS_UNMOUNT:
4449 case PRIV_VFS_MOUNT_NONUSER:
4450 case PRIV_VFS_MOUNT_OWNER:
4451 pr = cred->cr_prison;
4452 prison_lock(pr);
4453 if (pr->pr_allow & PR_ALLOW_MOUNT && pr->pr_enforce_statfs < 2)
4454 error = 0;
4455 else
4456 error = EPERM;
4457 prison_unlock(pr);
4458 return (error);
4459
4460 /*
4461 * Jails should hold no disposition on the PRIV_VFS_READ_DIR
4462 * policy. priv_check_cred will not specifically allow it, and
4463 * we may want a MAC policy to allow it.
4464 */
4465 case PRIV_VFS_READ_DIR:
4466 return (0);
4467
4468 /*
4469 * Conditionally allow privileged process in the jail to
4470 * manipulate filesystem extended attributes in the system
4471 * namespace.
4472 */
4473 case PRIV_VFS_EXTATTR_SYSTEM:
4474 if ((cred->cr_prison->pr_allow & PR_ALLOW_EXTATTR) != 0)
4475 return (0);
4476 else
4477 return (EPERM);
4478
4479 /*
4480 * Conditionnaly allow locking (unlocking) physical pages
4481 * in memory.
4482 */
4483 case PRIV_VM_MLOCK:
4484 case PRIV_VM_MUNLOCK:
4485 if (cred->cr_prison->pr_allow & PR_ALLOW_MLOCK)
4486 return (0);
4487 else
4488 return (EPERM);
4489
4490 /*
4491 * Conditionally allow jailed root to bind reserved ports.
4492 */
4493 case PRIV_NETINET_RESERVEDPORT:
4494 if (cred->cr_prison->pr_allow & PR_ALLOW_RESERVED_PORTS)
4495 return (0);
4496 else
4497 return (EPERM);
4498
4499 /*
4500 * Allow jailed root to reuse in-use ports.
4501 */
4502 case PRIV_NETINET_REUSEPORT:
4503 return (0);
4504
4505 /*
4506 * Allow jailed root to set certain IPv4/6 (option) headers.
4507 */
4508 case PRIV_NETINET_SETHDROPTS:
4509 return (0);
4510
4511 /*
4512 * Conditionally allow creating raw sockets in jail.
4513 */
4514 case PRIV_NETINET_RAW:
4515 if (cred->cr_prison->pr_allow & PR_ALLOW_RAW_SOCKETS)
4516 return (0);
4517 else
4518 return (EPERM);
4519
4520 /*
4521 * Since jail implements its own visibility limits on netstat
4522 * sysctls, allow getcred. This allows identd to work in
4523 * jail.
4524 */
4525 case PRIV_NETINET_GETCRED:
4526 return (0);
4527
4528 /*
4529 * Allow jailed root to set loginclass.
4530 */
4531 case PRIV_PROC_SETLOGINCLASS:
4532 return (0);
4533
4534 /*
4535 * Do not allow a process inside a jail to read the kernel
4536 * message buffer unless explicitly permitted.
4537 */
4538 case PRIV_MSGBUF:
4539 if (cred->cr_prison->pr_allow & PR_ALLOW_READ_MSGBUF)
4540 return (0);
4541 return (EPERM);
4542
4543 /*
4544 * Conditionally allow privileged process in the jail adjust
4545 * machine time.
4546 */
4547 case PRIV_ADJTIME:
4548 case PRIV_NTP_ADJTIME:
4549 if (cred->cr_prison->pr_allow &
4550 (PR_ALLOW_ADJTIME | PR_ALLOW_SETTIME)) {
4551 return (0);
4552 }
4553 return (EPERM);
4554
4555 /*
4556 * Conditionally allow privileged process in the jail set
4557 * machine time.
4558 */
4559 case PRIV_SETTIMEOFDAY:
4560 case PRIV_CLOCK_SETTIME:
4561 if (cred->cr_prison->pr_allow & PR_ALLOW_SETTIME)
4562 return (0);
4563 else
4564 return (EPERM);
4565
4566 /*
4567 * Conditionally allow privileged process in the jail to modify
4568 * the routing table.
4569 */
4570 case PRIV_NET_ROUTE:
4571 if (cred->cr_prison->pr_allow & PR_ALLOW_ROUTING)
4572 return (0);
4573 else
4574 return (EPERM);
4575
4576 default:
4577 /*
4578 * In all remaining cases, deny the privilege request. This
4579 * includes almost all network privileges, many system
4580 * configuration privileges.
4581 */
4582 return (EPERM);
4583 }
4584 }
4585
4586 /*
4587 * Return the part of pr2's name that is relative to pr1, or the whole name
4588 * if it does not directly follow.
4589 */
4590
4591 char *
prison_name(struct prison * pr1,struct prison * pr2)4592 prison_name(struct prison *pr1, struct prison *pr2)
4593 {
4594 char *name;
4595
4596 /* Jails see themselves as "0" (if they see themselves at all). */
4597 if (pr1 == pr2)
4598 return "0";
4599 name = pr2->pr_name;
4600 if (prison_ischild(pr1, pr2)) {
4601 /*
4602 * pr1 isn't locked (and allprison_lock may not be either)
4603 * so its length can't be counted on. But the number of dots
4604 * can be counted on - and counted.
4605 */
4606 for (; pr1 != &prison0; pr1 = pr1->pr_parent)
4607 name = strchr(name, '.') + 1;
4608 }
4609 return (name);
4610 }
4611
4612 /*
4613 * Return the part of pr2's path that is relative to pr1, or the whole path
4614 * if it does not directly follow.
4615 */
4616 static char *
prison_path(struct prison * pr1,struct prison * pr2)4617 prison_path(struct prison *pr1, struct prison *pr2)
4618 {
4619 char *path1, *path2;
4620 int len1;
4621
4622 path1 = pr1->pr_path;
4623 path2 = pr2->pr_path;
4624 if (!strcmp(path1, "/"))
4625 return (path2);
4626 len1 = strlen(path1);
4627 if (strncmp(path1, path2, len1))
4628 return (path2);
4629 if (path2[len1] == '\0')
4630 return "/";
4631 if (path2[len1] == '/')
4632 return (path2 + len1);
4633 return (path2);
4634 }
4635
4636 /*
4637 * Jail-related sysctls.
4638 */
4639 SYSCTL_NODE(_security, OID_AUTO, jail, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
4640 "Jails");
4641
4642 #if defined(INET) || defined(INET6)
4643 /*
4644 * Copy address array to memory that would be then SYSCTL_OUT-ed.
4645 * sysctl_jail_list() helper.
4646 */
4647 static void
prison_ip_copyout(struct prison * pr,const pr_family_t af,void ** out,int * len)4648 prison_ip_copyout(struct prison *pr, const pr_family_t af, void **out, int *len)
4649 {
4650 const struct prison_ip *pip;
4651 const size_t size = pr_families[af].size;
4652
4653 again:
4654 mtx_assert(&pr->pr_mtx, MA_OWNED);
4655 if ((pip = pr->pr_addrs[af]) != NULL) {
4656 if (*len < pip->ips) {
4657 *len = pip->ips;
4658 mtx_unlock(&pr->pr_mtx);
4659 *out = realloc(*out, *len * size, M_TEMP, M_WAITOK);
4660 mtx_lock(&pr->pr_mtx);
4661 goto again;
4662 }
4663 bcopy(pip->pr_ip, *out, pip->ips * size);
4664 }
4665 }
4666 #endif
4667
4668 static int
sysctl_jail_list(SYSCTL_HANDLER_ARGS)4669 sysctl_jail_list(SYSCTL_HANDLER_ARGS)
4670 {
4671 struct xprison *xp;
4672 struct prison *pr, *cpr;
4673 #ifdef INET
4674 struct in_addr *ip4 = NULL;
4675 int ip4s = 0;
4676 #endif
4677 #ifdef INET6
4678 struct in6_addr *ip6 = NULL;
4679 int ip6s = 0;
4680 #endif
4681 int descend, error;
4682
4683 xp = malloc(sizeof(*xp), M_TEMP, M_WAITOK);
4684 pr = req->td->td_ucred->cr_prison;
4685 error = 0;
4686 sx_slock(&allprison_lock);
4687 FOREACH_PRISON_DESCENDANT(pr, cpr, descend) {
4688 mtx_lock(&cpr->pr_mtx);
4689 #ifdef INET
4690 prison_ip_copyout(cpr, PR_INET, (void **)&ip4, &ip4s);
4691 #endif
4692 #ifdef INET6
4693 prison_ip_copyout(cpr, PR_INET6, (void **)&ip6, &ip6s);
4694 #endif
4695 bzero(xp, sizeof(*xp));
4696 xp->pr_version = XPRISON_VERSION;
4697 xp->pr_id = cpr->pr_id;
4698 xp->pr_state = cpr->pr_state;
4699 strlcpy(xp->pr_path, prison_path(pr, cpr), sizeof(xp->pr_path));
4700 strlcpy(xp->pr_host, cpr->pr_hostname, sizeof(xp->pr_host));
4701 strlcpy(xp->pr_name, prison_name(pr, cpr), sizeof(xp->pr_name));
4702 #ifdef INET
4703 xp->pr_ip4s = ip4s;
4704 #endif
4705 #ifdef INET6
4706 xp->pr_ip6s = ip6s;
4707 #endif
4708 mtx_unlock(&cpr->pr_mtx);
4709 error = SYSCTL_OUT(req, xp, sizeof(*xp));
4710 if (error)
4711 break;
4712 #ifdef INET
4713 if (xp->pr_ip4s > 0) {
4714 error = SYSCTL_OUT(req, ip4,
4715 xp->pr_ip4s * sizeof(struct in_addr));
4716 if (error)
4717 break;
4718 }
4719 #endif
4720 #ifdef INET6
4721 if (xp->pr_ip6s > 0) {
4722 error = SYSCTL_OUT(req, ip6,
4723 xp->pr_ip6s * sizeof(struct in6_addr));
4724 if (error)
4725 break;
4726 }
4727 #endif
4728 }
4729 sx_sunlock(&allprison_lock);
4730 free(xp, M_TEMP);
4731 #ifdef INET
4732 free(ip4, M_TEMP);
4733 #endif
4734 #ifdef INET6
4735 free(ip6, M_TEMP);
4736 #endif
4737 return (error);
4738 }
4739
4740 SYSCTL_OID(_security_jail, OID_AUTO, list,
4741 CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
4742 sysctl_jail_list, "S", "List of active jails");
4743
4744 static int
sysctl_jail_jailed(SYSCTL_HANDLER_ARGS)4745 sysctl_jail_jailed(SYSCTL_HANDLER_ARGS)
4746 {
4747 int error, injail;
4748
4749 injail = jailed(req->td->td_ucred);
4750 error = SYSCTL_OUT(req, &injail, sizeof(injail));
4751
4752 return (error);
4753 }
4754
4755 SYSCTL_PROC(_security_jail, OID_AUTO, jailed,
4756 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
4757 sysctl_jail_jailed, "I", "Process in jail?");
4758
4759 static int
sysctl_jail_vnet(SYSCTL_HANDLER_ARGS)4760 sysctl_jail_vnet(SYSCTL_HANDLER_ARGS)
4761 {
4762 int error, havevnet;
4763 #ifdef VIMAGE
4764 struct ucred *cred = req->td->td_ucred;
4765
4766 havevnet = jailed(cred) && prison_owns_vnet(cred->cr_prison);
4767 #else
4768 havevnet = 0;
4769 #endif
4770 error = SYSCTL_OUT(req, &havevnet, sizeof(havevnet));
4771
4772 return (error);
4773 }
4774
4775 SYSCTL_PROC(_security_jail, OID_AUTO, vnet,
4776 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
4777 sysctl_jail_vnet, "I", "Jail owns vnet?");
4778
4779 #if defined(INET) || defined(INET6)
4780 SYSCTL_UINT(_security_jail, OID_AUTO, jail_max_af_ips, CTLFLAG_RW,
4781 &jail_max_af_ips, 0,
4782 "Number of IP addresses a jail may have at most per address family (deprecated)");
4783 #endif
4784
4785 /*
4786 * Default parameters for jail(2) compatibility. For historical reasons,
4787 * the sysctl names have varying similarity to the parameter names. Prisons
4788 * just see their own parameters, and can't change them.
4789 */
4790 static int
sysctl_jail_default_allow(SYSCTL_HANDLER_ARGS)4791 sysctl_jail_default_allow(SYSCTL_HANDLER_ARGS)
4792 {
4793 int error, i;
4794
4795 /* Get the current flag value, and convert it to a boolean. */
4796 if (req->td->td_ucred->cr_prison == &prison0) {
4797 mtx_lock(&prison0.pr_mtx);
4798 i = (jail_default_allow & arg2) != 0;
4799 mtx_unlock(&prison0.pr_mtx);
4800 } else
4801 i = prison_allow(req->td->td_ucred, arg2);
4802
4803 if (arg1 != NULL)
4804 i = !i;
4805 error = sysctl_handle_int(oidp, &i, 0, req);
4806 if (error || !req->newptr)
4807 return (error);
4808 i = i ? arg2 : 0;
4809 if (arg1 != NULL)
4810 i ^= arg2;
4811 /*
4812 * The sysctls don't have CTLFLAGS_PRISON, so assume prison0
4813 * for writing.
4814 */
4815 mtx_lock(&prison0.pr_mtx);
4816 jail_default_allow = (jail_default_allow & ~arg2) | i;
4817 mtx_unlock(&prison0.pr_mtx);
4818 return (0);
4819 }
4820
4821 SYSCTL_PROC(_security_jail, OID_AUTO, set_hostname_allowed,
4822 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4823 NULL, PR_ALLOW_SET_HOSTNAME, sysctl_jail_default_allow, "I",
4824 "Processes in jail can set their hostnames (deprecated)");
4825 SYSCTL_PROC(_security_jail, OID_AUTO, socket_unixiproute_only,
4826 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4827 (void *)1, PR_ALLOW_SOCKET_AF, sysctl_jail_default_allow, "I",
4828 "Processes in jail are limited to creating UNIX/IP/route sockets only (deprecated)");
4829 SYSCTL_PROC(_security_jail, OID_AUTO, sysvipc_allowed,
4830 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4831 NULL, PR_ALLOW_SYSVIPC, sysctl_jail_default_allow, "I",
4832 "Processes in jail can use System V IPC primitives (deprecated)");
4833 SYSCTL_PROC(_security_jail, OID_AUTO, allow_raw_sockets,
4834 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4835 NULL, PR_ALLOW_RAW_SOCKETS, sysctl_jail_default_allow, "I",
4836 "Prison root can create raw sockets (deprecated)");
4837 SYSCTL_PROC(_security_jail, OID_AUTO, chflags_allowed,
4838 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4839 NULL, PR_ALLOW_CHFLAGS, sysctl_jail_default_allow, "I",
4840 "Processes in jail can alter system file flags (deprecated)");
4841 SYSCTL_PROC(_security_jail, OID_AUTO, mount_allowed,
4842 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4843 NULL, PR_ALLOW_MOUNT, sysctl_jail_default_allow, "I",
4844 "Processes in jail can mount/unmount jail-friendly file systems (deprecated)");
4845 SYSCTL_PROC(_security_jail, OID_AUTO, mlock_allowed,
4846 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4847 NULL, PR_ALLOW_MLOCK, sysctl_jail_default_allow, "I",
4848 "Processes in jail can lock/unlock physical pages in memory");
4849
4850 static int
sysctl_jail_default_level(SYSCTL_HANDLER_ARGS)4851 sysctl_jail_default_level(SYSCTL_HANDLER_ARGS)
4852 {
4853 struct prison *pr;
4854 int level, error;
4855
4856 pr = req->td->td_ucred->cr_prison;
4857 level = (pr == &prison0) ? *(int *)arg1 : *(int *)((char *)pr + arg2);
4858 error = sysctl_handle_int(oidp, &level, 0, req);
4859 if (error || !req->newptr)
4860 return (error);
4861 *(int *)arg1 = level;
4862 return (0);
4863 }
4864
4865 SYSCTL_PROC(_security_jail, OID_AUTO, enforce_statfs,
4866 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
4867 &jail_default_enforce_statfs, offsetof(struct prison, pr_enforce_statfs),
4868 sysctl_jail_default_level, "I",
4869 "Processes in jail cannot see all mounted file systems (deprecated)");
4870
4871 SYSCTL_PROC(_security_jail, OID_AUTO, devfs_ruleset,
4872 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
4873 &jail_default_devfs_rsnum, offsetof(struct prison, pr_devfs_rsnum),
4874 sysctl_jail_default_level, "I",
4875 "Ruleset for the devfs filesystem in jail (deprecated)");
4876
4877 SYSCTL_NODE(_security_jail, OID_AUTO, children, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
4878 "Limits and stats of child jails");
4879
4880 static int
sysctl_jail_children(SYSCTL_HANDLER_ARGS)4881 sysctl_jail_children(SYSCTL_HANDLER_ARGS)
4882 {
4883 struct prison *pr;
4884 int i;
4885
4886 pr = req->td->td_ucred->cr_prison;
4887
4888 switch (oidp->oid_kind & CTLTYPE) {
4889 case CTLTYPE_INT:
4890 i = *(int *)((char *)pr + arg2);
4891 return (SYSCTL_OUT(req, &i, sizeof(i)));
4892 }
4893
4894 return (0);
4895 }
4896
4897 SYSCTL_PROC(_security_jail_children, OID_AUTO, max,
4898 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
4899 NULL, offsetof(struct prison, pr_childmax), sysctl_jail_children,
4900 "I", "Maximum number of child jails");
4901 SYSCTL_PROC(_security_jail_children, OID_AUTO, cur,
4902 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
4903 NULL, offsetof(struct prison, pr_childcount), sysctl_jail_children,
4904 "I", "Current number of child jails");
4905
4906 /*
4907 * Nodes to describe jail parameters. Maximum length of string parameters
4908 * is returned in the string itself, and the other parameters exist merely
4909 * to make themselves and their types known.
4910 */
4911 SYSCTL_NODE(_security_jail, OID_AUTO, param, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
4912 "Jail parameters");
4913
4914 int
sysctl_jail_param(SYSCTL_HANDLER_ARGS)4915 sysctl_jail_param(SYSCTL_HANDLER_ARGS)
4916 {
4917 int i;
4918 long l;
4919 size_t s;
4920 char numbuf[12];
4921
4922 switch (oidp->oid_kind & CTLTYPE)
4923 {
4924 case CTLTYPE_LONG:
4925 case CTLTYPE_ULONG:
4926 l = 0;
4927 #ifdef SCTL_MASK32
4928 if (!(req->flags & SCTL_MASK32))
4929 #endif
4930 return (SYSCTL_OUT(req, &l, sizeof(l)));
4931 case CTLTYPE_INT:
4932 case CTLTYPE_UINT:
4933 i = 0;
4934 return (SYSCTL_OUT(req, &i, sizeof(i)));
4935 case CTLTYPE_STRING:
4936 snprintf(numbuf, sizeof(numbuf), "%jd", (intmax_t)arg2);
4937 return
4938 (sysctl_handle_string(oidp, numbuf, sizeof(numbuf), req));
4939 case CTLTYPE_STRUCT:
4940 s = (size_t)arg2;
4941 return (SYSCTL_OUT(req, &s, sizeof(s)));
4942 }
4943 return (0);
4944 }
4945
4946 /*
4947 * CTLFLAG_RDTUN in the following indicates jail parameters that can be set at
4948 * jail creation time but cannot be changed in an existing jail.
4949 */
4950 SYSCTL_JAIL_PARAM(, jid, CTLTYPE_INT | CTLFLAG_RDTUN, "I", "Jail ID");
4951 SYSCTL_JAIL_PARAM(, parent, CTLTYPE_INT | CTLFLAG_RD, "I", "Jail parent ID");
4952 SYSCTL_JAIL_PARAM_STRING(, name, CTLFLAG_RW, MAXHOSTNAMELEN, "Jail name");
4953 SYSCTL_JAIL_PARAM_STRING(, path, CTLFLAG_RDTUN, MAXPATHLEN, "Jail root path");
4954 SYSCTL_JAIL_PARAM(, securelevel, CTLTYPE_INT | CTLFLAG_RW,
4955 "I", "Jail secure level");
4956 SYSCTL_JAIL_PARAM(, osreldate, CTLTYPE_INT | CTLFLAG_RDTUN, "I",
4957 "Jail value for kern.osreldate and uname -K");
4958 SYSCTL_JAIL_PARAM_STRING(, osrelease, CTLFLAG_RDTUN, OSRELEASELEN,
4959 "Jail value for kern.osrelease and uname -r");
4960 SYSCTL_JAIL_PARAM(, enforce_statfs, CTLTYPE_INT | CTLFLAG_RW,
4961 "I", "Jail cannot see all mounted file systems");
4962 SYSCTL_JAIL_PARAM(, devfs_ruleset, CTLTYPE_INT | CTLFLAG_RW,
4963 "I", "Ruleset for in-jail devfs mounts");
4964 SYSCTL_JAIL_PARAM(, persist, CTLTYPE_INT | CTLFLAG_RW,
4965 "B", "Jail persistence");
4966 #ifdef VIMAGE
4967 SYSCTL_JAIL_PARAM(, vnet, CTLTYPE_INT | CTLFLAG_RDTUN,
4968 "E,jailsys", "Virtual network stack");
4969 #endif
4970 SYSCTL_JAIL_PARAM(, dying, CTLTYPE_INT | CTLFLAG_RD,
4971 "B", "Jail is in the process of shutting down");
4972
4973 SYSCTL_JAIL_PARAM_NODE(children, "Number of child jails");
4974 SYSCTL_JAIL_PARAM(_children, cur, CTLTYPE_INT | CTLFLAG_RD,
4975 "I", "Current number of child jails");
4976 SYSCTL_JAIL_PARAM(_children, max, CTLTYPE_INT | CTLFLAG_RW,
4977 "I", "Maximum number of child jails");
4978
4979 SYSCTL_JAIL_PARAM_SYS_NODE(host, CTLFLAG_RW, "Jail host info");
4980 SYSCTL_JAIL_PARAM_STRING(_host, hostname, CTLFLAG_RW, MAXHOSTNAMELEN,
4981 "Jail hostname");
4982 SYSCTL_JAIL_PARAM_STRING(_host, domainname, CTLFLAG_RW, MAXHOSTNAMELEN,
4983 "Jail NIS domainname");
4984 SYSCTL_JAIL_PARAM_STRING(_host, hostuuid, CTLFLAG_RW, HOSTUUIDLEN,
4985 "Jail host UUID");
4986 SYSCTL_JAIL_PARAM(_host, hostid, CTLTYPE_ULONG | CTLFLAG_RW,
4987 "LU", "Jail host ID");
4988
4989 SYSCTL_JAIL_PARAM_NODE(cpuset, "Jail cpuset");
4990 SYSCTL_JAIL_PARAM(_cpuset, id, CTLTYPE_INT | CTLFLAG_RD, "I", "Jail cpuset ID");
4991
4992 #ifdef INET
4993 SYSCTL_JAIL_PARAM_SYS_NODE(ip4, CTLFLAG_RDTUN,
4994 "Jail IPv4 address virtualization");
4995 SYSCTL_JAIL_PARAM_STRUCT(_ip4, addr, CTLFLAG_RW, sizeof(struct in_addr),
4996 "S,in_addr,a", "Jail IPv4 addresses");
4997 SYSCTL_JAIL_PARAM(_ip4, saddrsel, CTLTYPE_INT | CTLFLAG_RW,
4998 "B", "Do (not) use IPv4 source address selection rather than the "
4999 "primary jail IPv4 address.");
5000 #endif
5001 #ifdef INET6
5002 SYSCTL_JAIL_PARAM_SYS_NODE(ip6, CTLFLAG_RDTUN,
5003 "Jail IPv6 address virtualization");
5004 SYSCTL_JAIL_PARAM_STRUCT(_ip6, addr, CTLFLAG_RW, sizeof(struct in6_addr),
5005 "S,in6_addr,a", "Jail IPv6 addresses");
5006 SYSCTL_JAIL_PARAM(_ip6, saddrsel, CTLTYPE_INT | CTLFLAG_RW,
5007 "B", "Do (not) use IPv6 source address selection rather than the "
5008 "primary jail IPv6 address.");
5009 #endif
5010
5011 SYSCTL_JAIL_PARAM_NODE(allow, "Jail permission flags");
5012 SYSCTL_JAIL_PARAM(_allow, set_hostname, CTLTYPE_INT | CTLFLAG_RW,
5013 "B", "Jail may set hostname");
5014 SYSCTL_JAIL_PARAM(_allow, sysvipc, CTLTYPE_INT | CTLFLAG_RW,
5015 "B", "Jail may use SYSV IPC");
5016 SYSCTL_JAIL_PARAM(_allow, raw_sockets, CTLTYPE_INT | CTLFLAG_RW,
5017 "B", "Jail may create raw sockets");
5018 SYSCTL_JAIL_PARAM(_allow, chflags, CTLTYPE_INT | CTLFLAG_RW,
5019 "B", "Jail may alter system file flags");
5020 SYSCTL_JAIL_PARAM(_allow, quotas, CTLTYPE_INT | CTLFLAG_RW,
5021 "B", "Jail may set file quotas");
5022 SYSCTL_JAIL_PARAM(_allow, socket_af, CTLTYPE_INT | CTLFLAG_RW,
5023 "B", "Jail may create sockets other than just UNIX/IPv4/IPv6/route");
5024 SYSCTL_JAIL_PARAM(_allow, mlock, CTLTYPE_INT | CTLFLAG_RW,
5025 "B", "Jail may lock (unlock) physical pages in memory");
5026 SYSCTL_JAIL_PARAM(_allow, reserved_ports, CTLTYPE_INT | CTLFLAG_RW,
5027 "B", "Jail may bind sockets to reserved ports");
5028 SYSCTL_JAIL_PARAM(_allow, read_msgbuf, CTLTYPE_INT | CTLFLAG_RW,
5029 "B", "Jail may read the kernel message buffer");
5030 SYSCTL_JAIL_PARAM(_allow, unprivileged_proc_debug, CTLTYPE_INT | CTLFLAG_RW,
5031 "B", "Unprivileged processes may use process debugging facilities");
5032 SYSCTL_JAIL_PARAM(_allow, unprivileged_parent_tampering,
5033 CTLTYPE_INT | CTLFLAG_RW, "B",
5034 "Unprivileged parent jail processes may tamper with same-uid processes"
5035 " (signal/debug/cpuset)");
5036 SYSCTL_JAIL_PARAM(_allow, suser, CTLTYPE_INT | CTLFLAG_RW,
5037 "B", "Processes in jail with uid 0 have privilege");
5038 #ifdef VIMAGE
5039 SYSCTL_JAIL_PARAM(_allow, nfsd, CTLTYPE_INT | CTLFLAG_RW,
5040 "B", "Mountd/nfsd may run in the jail");
5041 #endif
5042 SYSCTL_JAIL_PARAM(_allow, extattr, CTLTYPE_INT | CTLFLAG_RW,
5043 "B", "Jail may set system-level filesystem extended attributes");
5044 SYSCTL_JAIL_PARAM(_allow, adjtime, CTLTYPE_INT | CTLFLAG_RW,
5045 "B", "Jail may adjust system time");
5046 SYSCTL_JAIL_PARAM(_allow, settime, CTLTYPE_INT | CTLFLAG_RW,
5047 "B", "Jail may set system time");
5048 SYSCTL_JAIL_PARAM(_allow, routing, CTLTYPE_INT | CTLFLAG_RW,
5049 "B", "Jail may modify routing table");
5050 #ifdef AUDIT
5051 SYSCTL_JAIL_PARAM(_allow, setaudit, CTLTYPE_INT | CTLFLAG_RW,
5052 "B", "Jail may set and get audit session state");
5053 #endif
5054
5055 SYSCTL_JAIL_PARAM_SUBNODE(allow, mount, "Jail mount/unmount permission flags");
5056 SYSCTL_JAIL_PARAM(_allow_mount, , CTLTYPE_INT | CTLFLAG_RW,
5057 "B", "Jail may mount/unmount jail-friendly file systems in general");
5058
5059 /*
5060 * Add a dynamic parameter allow.<name>, or allow.<prefix>.<name>. Return
5061 * its associated bit in the pr_allow bitmask, or zero if the parameter was
5062 * not created.
5063 */
5064 unsigned
prison_add_allow(const char * prefix,const char * name,const char * prefix_descr,const char * descr)5065 prison_add_allow(const char *prefix, const char *name, const char *prefix_descr,
5066 const char *descr)
5067 {
5068 struct bool_flags *bf;
5069 struct sysctl_oid *parent;
5070 char *allow_name, *allow_noname, *allowed;
5071 #ifndef NO_SYSCTL_DESCR
5072 char *descr_deprecated;
5073 #endif
5074 u_int allow_flag;
5075
5076 if (prefix
5077 ? asprintf(&allow_name, M_PRISON, "allow.%s.%s", prefix, name)
5078 < 0 ||
5079 asprintf(&allow_noname, M_PRISON, "allow.%s.no%s", prefix, name)
5080 < 0
5081 : asprintf(&allow_name, M_PRISON, "allow.%s", name) < 0 ||
5082 asprintf(&allow_noname, M_PRISON, "allow.no%s", name) < 0) {
5083 free(allow_name, M_PRISON);
5084 return 0;
5085 }
5086
5087 /*
5088 * See if this parameter has already beed added, i.e. a module was
5089 * previously loaded/unloaded.
5090 */
5091 mtx_lock(&prison0.pr_mtx);
5092 for (bf = pr_flag_allow;
5093 bf < pr_flag_allow + nitems(pr_flag_allow) &&
5094 atomic_load_int(&bf->flag) != 0;
5095 bf++) {
5096 if (strcmp(bf->name, allow_name) == 0) {
5097 allow_flag = bf->flag;
5098 goto no_add;
5099 }
5100 }
5101
5102 /*
5103 * Find a free bit in pr_allow_all, failing if there are none
5104 * (which shouldn't happen as long as we keep track of how many
5105 * potential dynamic flags exist).
5106 */
5107 for (allow_flag = 1;; allow_flag <<= 1) {
5108 if (allow_flag == 0)
5109 goto no_add;
5110 if ((pr_allow_all & allow_flag) == 0)
5111 break;
5112 }
5113
5114 /* Note the parameter in the next open slot in pr_flag_allow. */
5115 for (bf = pr_flag_allow; ; bf++) {
5116 if (bf == pr_flag_allow + nitems(pr_flag_allow)) {
5117 /* This should never happen, but is not fatal. */
5118 allow_flag = 0;
5119 goto no_add;
5120 }
5121 if (atomic_load_int(&bf->flag) == 0)
5122 break;
5123 }
5124 bf->name = allow_name;
5125 bf->noname = allow_noname;
5126 pr_allow_all |= allow_flag;
5127 /*
5128 * prison0 always has permission for the new parameter.
5129 * Other jails must have it granted to them.
5130 */
5131 prison0.pr_allow |= allow_flag;
5132 /* The flag indicates a valid entry, so make sure it is set last. */
5133 atomic_store_rel_int(&bf->flag, allow_flag);
5134 mtx_unlock(&prison0.pr_mtx);
5135
5136 /*
5137 * Create sysctls for the parameter, and the back-compat global
5138 * permission.
5139 */
5140 parent = prefix
5141 ? SYSCTL_ADD_NODE(NULL,
5142 SYSCTL_CHILDREN(&sysctl___security_jail_param_allow),
5143 OID_AUTO, prefix, CTLFLAG_MPSAFE, 0, prefix_descr)
5144 : &sysctl___security_jail_param_allow;
5145 (void)SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(parent), OID_AUTO,
5146 name, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
5147 NULL, 0, sysctl_jail_param, "B", descr);
5148 if ((prefix
5149 ? asprintf(&allowed, M_TEMP, "%s_%s_allowed", prefix, name)
5150 : asprintf(&allowed, M_TEMP, "%s_allowed", name)) >= 0) {
5151 #ifndef NO_SYSCTL_DESCR
5152 (void)asprintf(&descr_deprecated, M_TEMP, "%s (deprecated)",
5153 descr);
5154 #endif
5155 (void)SYSCTL_ADD_PROC(NULL,
5156 SYSCTL_CHILDREN(&sysctl___security_jail), OID_AUTO, allowed,
5157 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, NULL, allow_flag,
5158 sysctl_jail_default_allow, "I", descr_deprecated);
5159 #ifndef NO_SYSCTL_DESCR
5160 free(descr_deprecated, M_TEMP);
5161 #endif
5162 free(allowed, M_TEMP);
5163 }
5164 return allow_flag;
5165
5166 no_add:
5167 mtx_unlock(&prison0.pr_mtx);
5168 free(allow_name, M_PRISON);
5169 free(allow_noname, M_PRISON);
5170 return allow_flag;
5171 }
5172
5173 /*
5174 * The VFS system will register jail-aware filesystems here. They each get
5175 * a parameter allow.mount.xxxfs and a flag to check when a jailed user
5176 * attempts to mount.
5177 */
5178 void
prison_add_vfs(struct vfsconf * vfsp)5179 prison_add_vfs(struct vfsconf *vfsp)
5180 {
5181 #ifdef NO_SYSCTL_DESCR
5182
5183 vfsp->vfc_prison_flag = prison_add_allow("mount", vfsp->vfc_name,
5184 NULL, NULL);
5185 #else
5186 char *descr;
5187
5188 (void)asprintf(&descr, M_TEMP, "Jail may mount the %s file system",
5189 vfsp->vfc_name);
5190 vfsp->vfc_prison_flag = prison_add_allow("mount", vfsp->vfc_name,
5191 NULL, descr);
5192 free(descr, M_TEMP);
5193 #endif
5194 }
5195
5196 #ifdef RACCT
5197 void
prison_racct_foreach(void (* callback)(struct racct * racct,void * arg2,void * arg3),void (* pre)(void),void (* post)(void),void * arg2,void * arg3)5198 prison_racct_foreach(void (*callback)(struct racct *racct,
5199 void *arg2, void *arg3), void (*pre)(void), void (*post)(void),
5200 void *arg2, void *arg3)
5201 {
5202 struct prison_racct *prr;
5203
5204 ASSERT_RACCT_ENABLED();
5205
5206 sx_slock(&allprison_lock);
5207 if (pre != NULL)
5208 (pre)();
5209 LIST_FOREACH(prr, &allprison_racct, prr_next)
5210 (callback)(prr->prr_racct, arg2, arg3);
5211 if (post != NULL)
5212 (post)();
5213 sx_sunlock(&allprison_lock);
5214 }
5215
5216 static struct prison_racct *
prison_racct_find_locked(const char * name)5217 prison_racct_find_locked(const char *name)
5218 {
5219 struct prison_racct *prr;
5220
5221 ASSERT_RACCT_ENABLED();
5222 sx_assert(&allprison_lock, SA_XLOCKED);
5223
5224 if (name[0] == '\0' || strlen(name) >= MAXHOSTNAMELEN)
5225 return (NULL);
5226
5227 LIST_FOREACH(prr, &allprison_racct, prr_next) {
5228 if (strcmp(name, prr->prr_name) != 0)
5229 continue;
5230
5231 /* Found prison_racct with a matching name? */
5232 prison_racct_hold(prr);
5233 return (prr);
5234 }
5235
5236 /* Add new prison_racct. */
5237 prr = malloc(sizeof(*prr), M_PRISON_RACCT, M_ZERO | M_WAITOK);
5238 racct_create(&prr->prr_racct);
5239
5240 strcpy(prr->prr_name, name);
5241 refcount_init(&prr->prr_refcount, 1);
5242 LIST_INSERT_HEAD(&allprison_racct, prr, prr_next);
5243
5244 return (prr);
5245 }
5246
5247 struct prison_racct *
prison_racct_find(const char * name)5248 prison_racct_find(const char *name)
5249 {
5250 struct prison_racct *prr;
5251
5252 ASSERT_RACCT_ENABLED();
5253
5254 sx_xlock(&allprison_lock);
5255 prr = prison_racct_find_locked(name);
5256 sx_xunlock(&allprison_lock);
5257 return (prr);
5258 }
5259
5260 void
prison_racct_hold(struct prison_racct * prr)5261 prison_racct_hold(struct prison_racct *prr)
5262 {
5263
5264 ASSERT_RACCT_ENABLED();
5265
5266 refcount_acquire(&prr->prr_refcount);
5267 }
5268
5269 static void
prison_racct_free_locked(struct prison_racct * prr)5270 prison_racct_free_locked(struct prison_racct *prr)
5271 {
5272
5273 ASSERT_RACCT_ENABLED();
5274 sx_assert(&allprison_lock, SA_XLOCKED);
5275
5276 if (refcount_release(&prr->prr_refcount)) {
5277 racct_destroy(&prr->prr_racct);
5278 LIST_REMOVE(prr, prr_next);
5279 free(prr, M_PRISON_RACCT);
5280 }
5281 }
5282
5283 void
prison_racct_free(struct prison_racct * prr)5284 prison_racct_free(struct prison_racct *prr)
5285 {
5286
5287 ASSERT_RACCT_ENABLED();
5288 sx_assert(&allprison_lock, SA_UNLOCKED);
5289
5290 if (refcount_release_if_not_last(&prr->prr_refcount))
5291 return;
5292
5293 sx_xlock(&allprison_lock);
5294 prison_racct_free_locked(prr);
5295 sx_xunlock(&allprison_lock);
5296 }
5297
5298 static void
prison_racct_attach(struct prison * pr)5299 prison_racct_attach(struct prison *pr)
5300 {
5301 struct prison_racct *prr;
5302
5303 ASSERT_RACCT_ENABLED();
5304 sx_assert(&allprison_lock, SA_XLOCKED);
5305
5306 prr = prison_racct_find_locked(pr->pr_name);
5307 KASSERT(prr != NULL, ("cannot find prison_racct"));
5308
5309 pr->pr_prison_racct = prr;
5310 }
5311
5312 /*
5313 * Handle jail renaming. From the racct point of view, renaming means
5314 * moving from one prison_racct to another.
5315 */
5316 static void
prison_racct_modify(struct prison * pr)5317 prison_racct_modify(struct prison *pr)
5318 {
5319 #ifdef RCTL
5320 struct proc *p;
5321 struct ucred *cred;
5322 #endif
5323 struct prison_racct *oldprr;
5324
5325 ASSERT_RACCT_ENABLED();
5326
5327 sx_slock(&allproc_lock);
5328 sx_xlock(&allprison_lock);
5329
5330 if (strcmp(pr->pr_name, pr->pr_prison_racct->prr_name) == 0) {
5331 sx_xunlock(&allprison_lock);
5332 sx_sunlock(&allproc_lock);
5333 return;
5334 }
5335
5336 oldprr = pr->pr_prison_racct;
5337 pr->pr_prison_racct = NULL;
5338
5339 prison_racct_attach(pr);
5340
5341 /*
5342 * Move resource utilisation records.
5343 */
5344 racct_move(pr->pr_prison_racct->prr_racct, oldprr->prr_racct);
5345
5346 #ifdef RCTL
5347 /*
5348 * Force rctl to reattach rules to processes.
5349 */
5350 FOREACH_PROC_IN_SYSTEM(p) {
5351 PROC_LOCK(p);
5352 cred = crhold(p->p_ucred);
5353 PROC_UNLOCK(p);
5354 rctl_proc_ucred_changed(p, cred);
5355 crfree(cred);
5356 }
5357 #endif
5358
5359 sx_sunlock(&allproc_lock);
5360 prison_racct_free_locked(oldprr);
5361 sx_xunlock(&allprison_lock);
5362 }
5363
5364 static void
prison_racct_detach(struct prison * pr)5365 prison_racct_detach(struct prison *pr)
5366 {
5367
5368 ASSERT_RACCT_ENABLED();
5369 sx_assert(&allprison_lock, SA_UNLOCKED);
5370
5371 if (pr->pr_prison_racct == NULL)
5372 return;
5373 prison_racct_free(pr->pr_prison_racct);
5374 pr->pr_prison_racct = NULL;
5375 }
5376 #endif /* RACCT */
5377
5378 /*
5379 * Submit a knote for a prison, locking if necessary.
5380 */
5381 static void
prison_knote(struct prison * pr,long hint)5382 prison_knote(struct prison *pr, long hint)
5383 {
5384 int locked;
5385
5386 locked = mtx_owned(&pr->pr_mtx);
5387 if (!locked)
5388 mtx_lock(&pr->pr_mtx);
5389 KNOTE_LOCKED(pr->pr_klist, hint);
5390 jaildesc_knote(pr, hint);
5391 if (!locked)
5392 mtx_unlock(&pr->pr_mtx);
5393 }
5394
5395 #ifdef DDB
5396
5397 static void
db_show_prison(struct prison * pr)5398 db_show_prison(struct prison *pr)
5399 {
5400 struct bool_flags *bf;
5401 struct jailsys_flags *jsf;
5402 #if defined(INET) || defined(INET6)
5403 int ii;
5404 struct prison_ip *pip;
5405 #endif
5406 unsigned f;
5407 #ifdef INET
5408 char ip4buf[INET_ADDRSTRLEN];
5409 #endif
5410 #ifdef INET6
5411 char ip6buf[INET6_ADDRSTRLEN];
5412 #endif
5413
5414 db_printf("prison %p:\n", pr);
5415 db_printf(" jid = %d\n", pr->pr_id);
5416 db_printf(" name = %s\n", pr->pr_name);
5417 db_printf(" parent = %p\n", pr->pr_parent);
5418 db_printf(" ref = %d\n", pr->pr_ref);
5419 db_printf(" uref = %d\n", pr->pr_uref);
5420 db_printf(" state = %s\n",
5421 pr->pr_state == PRISON_STATE_ALIVE ? "alive" :
5422 pr->pr_state == PRISON_STATE_DYING ? "dying" :
5423 "invalid");
5424 db_printf(" path = %s\n", pr->pr_path);
5425 db_printf(" cpuset = %d\n", pr->pr_cpuset
5426 ? pr->pr_cpuset->cs_id : -1);
5427 #ifdef VIMAGE
5428 db_printf(" vnet = %p\n", pr->pr_vnet);
5429 #endif
5430 db_printf(" root = %p\n", pr->pr_root);
5431 db_printf(" securelevel = %d\n", pr->pr_securelevel);
5432 db_printf(" devfs_rsnum = %d\n", pr->pr_devfs_rsnum);
5433 db_printf(" children.max = %d\n", pr->pr_childmax);
5434 db_printf(" children.cur = %d\n", pr->pr_childcount);
5435 db_printf(" child = %p\n", LIST_FIRST(&pr->pr_children));
5436 db_printf(" sibling = %p\n", LIST_NEXT(pr, pr_sibling));
5437 db_printf(" flags = 0x%x", pr->pr_flags);
5438 for (bf = pr_flag_bool; bf < pr_flag_bool + nitems(pr_flag_bool); bf++)
5439 if (pr->pr_flags & bf->flag)
5440 db_printf(" %s", bf->name);
5441 for (jsf = pr_flag_jailsys;
5442 jsf < pr_flag_jailsys + nitems(pr_flag_jailsys);
5443 jsf++) {
5444 f = pr->pr_flags & (jsf->disable | jsf->new);
5445 db_printf(" %-16s= %s\n", jsf->name,
5446 (f != 0 && f == jsf->disable) ? "disable"
5447 : (f == jsf->new) ? "new"
5448 : "inherit");
5449 }
5450 db_printf(" allow = 0x%x", pr->pr_allow);
5451 for (bf = pr_flag_allow;
5452 bf < pr_flag_allow + nitems(pr_flag_allow) &&
5453 atomic_load_int(&bf->flag) != 0;
5454 bf++)
5455 if (pr->pr_allow & bf->flag)
5456 db_printf(" %s", bf->name);
5457 db_printf("\n");
5458 db_printf(" enforce_statfs = %d\n", pr->pr_enforce_statfs);
5459 db_printf(" host.hostname = %s\n", pr->pr_hostname);
5460 db_printf(" host.domainname = %s\n", pr->pr_domainname);
5461 db_printf(" host.hostuuid = %s\n", pr->pr_hostuuid);
5462 db_printf(" host.hostid = %lu\n", pr->pr_hostid);
5463 #ifdef INET
5464 if ((pip = pr->pr_addrs[PR_INET]) != NULL) {
5465 db_printf(" ip4s = %d\n", pip->ips);
5466 for (ii = 0; ii < pip->ips; ii++)
5467 db_printf(" %s %s\n",
5468 ii == 0 ? "ip4.addr =" : " ",
5469 inet_ntoa_r(
5470 *(const struct in_addr *)PR_IP(pip, PR_INET, ii),
5471 ip4buf));
5472 }
5473 #endif
5474 #ifdef INET6
5475 if ((pip = pr->pr_addrs[PR_INET6]) != NULL) {
5476 db_printf(" ip6s = %d\n", pip->ips);
5477 for (ii = 0; ii < pip->ips; ii++)
5478 db_printf(" %s %s\n",
5479 ii == 0 ? "ip6.addr =" : " ",
5480 ip6_sprintf(ip6buf,
5481 (const struct in6_addr *)PR_IP(pip, PR_INET6, ii)));
5482 }
5483 #endif
5484 }
5485
DB_SHOW_COMMAND(prison,db_show_prison_command)5486 DB_SHOW_COMMAND(prison, db_show_prison_command)
5487 {
5488 struct prison *pr;
5489
5490 if (!have_addr) {
5491 /*
5492 * Show all prisons in the list, and prison0 which is not
5493 * listed.
5494 */
5495 db_show_prison(&prison0);
5496 if (!db_pager_quit) {
5497 TAILQ_FOREACH(pr, &allprison, pr_list) {
5498 db_show_prison(pr);
5499 if (db_pager_quit)
5500 break;
5501 }
5502 }
5503 return;
5504 }
5505
5506 if (addr == 0)
5507 pr = &prison0;
5508 else {
5509 /* Look for a prison with the ID and with references. */
5510 TAILQ_FOREACH(pr, &allprison, pr_list)
5511 if (pr->pr_id == addr && pr->pr_ref > 0)
5512 break;
5513 if (pr == NULL)
5514 /* Look again, without requiring a reference. */
5515 TAILQ_FOREACH(pr, &allprison, pr_list)
5516 if (pr->pr_id == addr)
5517 break;
5518 if (pr == NULL)
5519 /* Assume address points to a valid prison. */
5520 pr = (struct prison *)addr;
5521 }
5522 db_show_prison(pr);
5523 }
5524
5525 #endif /* DDB */
5526