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