sys/kern/kern_jail.c

   1 /*
   2  * ----------------------------------------------------------------------------
   3  * "THE BEER-WARE LICENSE" (Revision 42):
   4  * <phk@FreeBSD.ORG> wrote this file.  As long as you retain this notice you
   5  * can do whatever you want with this stuff. If we meet some day, and you think
   6  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
   7  * ----------------------------------------------------------------------------
   8  *
   9  */
  10 /*-
  11  * Copyright (c) 2006 Victor Balada Diaz <victor@bsdes.net>
  12  * All rights reserved.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions
  16  * are met:
  17  * 1. Redistributions of source code must retain the above copyright
  18  *    notice, this list of conditions and the following disclaimer.
  19  * 2. Redistributions in binary form must reproduce the above copyright
  20  *    notice, this list of conditions and the following disclaimer in the
  21  *    documentation and/or other materials provided with the distribution.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36
  37 /*
  38  * $FreeBSD: src/sys/kern/kern_jail.c,v 1.6.2.3 2001/08/17 01:00:26 rwatson Exp $
  39  * $DragonFly: src/sys/kern/kern_jail.c,v 1.19 2008/05/17 18:20:33 dillon Exp $
  40  */
  41
  42 #include "opt_inet6.h"
  43
  44 #include <sys/param.h>
  45 #include <sys/types.h>
  46 #include <sys/kernel.h>
  47 #include <sys/systm.h>
  48 #include <sys/errno.h>
  49 #include <sys/sysproto.h>
  50 #include <sys/malloc.h>
  51 #include <sys/nlookup.h>
  52 #include <sys/namecache.h>
  53 #include <sys/proc.h>
  54 #include <sys/priv.h>
  55 #include <sys/jail.h>
  56 #include <sys/socket.h>
  57 #include <sys/sysctl.h>
  58 #include <sys/kern_syscall.h>
  59 #include <net/if.h>
  60 #include <netinet/in.h>
  61 #include <netinet6/in6_var.h>
  62
  63 #include <sys/mplock2.h>
  64
  65 static struct prison    *prison_find(int);
  66 static void             prison_ipcache_init(struct prison *);
  67
  68 MALLOC_DEFINE(M_PRISON, "prison", "Prison structures");
  69
  70 SYSCTL_NODE(, OID_AUTO, jail, CTLFLAG_RW, 0,
  71     "Jail rules");
  72
  73 int     jail_set_hostname_allowed = 1;
  74 SYSCTL_INT(_jail, OID_AUTO, set_hostname_allowed, CTLFLAG_RW,
  75     &jail_set_hostname_allowed, 0,
  76     "Processes in jail can set their hostnames");
  77
  78 int     jail_socket_unixiproute_only = 1;
  79 SYSCTL_INT(_jail, OID_AUTO, socket_unixiproute_only, CTLFLAG_RW,
  80     &jail_socket_unixiproute_only, 0,
  81     "Processes in jail are limited to creating UNIX/IPv[46]/route sockets only");
  82
  83 int     jail_sysvipc_allowed = 0;
  84 SYSCTL_INT(_jail, OID_AUTO, sysvipc_allowed, CTLFLAG_RW,
  85     &jail_sysvipc_allowed, 0,
  86     "Processes in jail can use System V IPC primitives");
  87
  88 int    jail_chflags_allowed = 0;
  89 SYSCTL_INT(_jail, OID_AUTO, chflags_allowed, CTLFLAG_RW,
  90     &jail_chflags_allowed, 0,
  91     "Process in jail can set chflags(1)");
  92
  93 int    jail_allow_raw_sockets = 0;
  94 SYSCTL_INT(_jail, OID_AUTO, allow_raw_sockets, CTLFLAG_RW,
  95     &jail_allow_raw_sockets, 0,
  96     "Process in jail can create raw sockets");
  97
  98 int     lastprid = 0;
  99 int     prisoncount = 0;
 100
 101 LIST_HEAD(prisonlist, prison);
 102 struct  prisonlist allprison = LIST_HEAD_INITIALIZER(&allprison);
 103
 104 static int
 105 kern_jail_attach(int jid)
 106 {
 107         struct proc *p = curthread->td_proc;
 108         struct prison *pr;
 109         struct ucred *cr;
 110         int error;
 111
 112         pr = prison_find(jid);
 113         if (pr == NULL)
 114                 return(EINVAL);
 115
 116         error = kern_chroot(&pr->pr_root);
 117         if (error)
 118                 return(error);
 119
 120         prison_hold(pr);
 121         lwkt_gettoken(&p->p_token);
 122         cr = cratom_proc(p);
 123         cr->cr_prison = pr;
 124         p->p_flags |= P_JAILED;
 125         lwkt_reltoken(&p->p_token);
 126
 127         return(0);
 128 }
 129
 130 static int
 131 assign_prison_id(struct prison *pr)
 132 {
 133         int tryprid;
 134         struct prison *tpr;
 135
 136         tryprid = lastprid + 1;
 137         if (tryprid == JAIL_MAX)
 138                 tryprid = 1;
 139 next:
 140         LIST_FOREACH(tpr, &allprison, pr_list) {
 141                 if (tpr->pr_id != tryprid)
 142                         continue;
 143                 tryprid++;
 144                 if (tryprid == JAIL_MAX) {
 145                         return (ERANGE);
 146                 }
 147                 goto next;
 148         }
 149         pr->pr_id = lastprid = tryprid;
 150
 151         return (0);
 152 }
 153
 154 static int
 155 kern_jail(struct prison *pr, struct jail *j)
 156 {
 157         int error;
 158         struct nlookupdata nd;
 159
 160         error = nlookup_init(&nd, j->path, UIO_USERSPACE, NLC_FOLLOW);
 161         if (error) {
 162                 nlookup_done(&nd);
 163                 return (error);
 164         }
 165         error = nlookup(&nd);
 166         if (error) {
 167                 nlookup_done(&nd);
 168                 return (error);
 169         }
 170         cache_copy(&nd.nl_nch, &pr->pr_root);
 171
 172         varsymset_init(&pr->pr_varsymset, NULL);
 173         prison_ipcache_init(pr);
 174
 175         error = assign_prison_id(pr);
 176         if (error) {
 177                 varsymset_clean(&pr->pr_varsymset);
 178                 nlookup_done(&nd);
 179                 return (error);
 180         }
 181
 182         LIST_INSERT_HEAD(&allprison, pr, pr_list);
 183         ++prisoncount;
 184
 185         error = kern_jail_attach(pr->pr_id);
 186         if (error) {
 187                 LIST_REMOVE(pr, pr_list);
 188                 --prisoncount;
 189                 varsymset_clean(&pr->pr_varsymset);
 190         }
 191         nlookup_done(&nd);
 192         return (error);
 193 }
 194
 195 /*
 196  * jail()
 197  *
 198  * jail_args(syscallarg(struct jail *) jail)
 199  *
 200  * MPALMOSTSAFE
 201  */
 202 int
 203 sys_jail(struct jail_args *uap)
 204 {
 205         struct thread *td = curthread;
 206         struct prison *pr;
 207         struct jail_ip_storage *jip;
 208         struct jail j;
 209         int error;
 210         uint32_t jversion;
 211
 212         uap->sysmsg_result = -1;
 213
 214         error = priv_check(td, PRIV_JAIL_CREATE);
 215         if (error)
 216                 return (error);
 217
 218         error = copyin(uap->jail, &jversion, sizeof(jversion));
 219         if (error)
 220                 return (error);
 221
 222         pr = kmalloc(sizeof(*pr), M_PRISON, M_WAITOK | M_ZERO);
 223         SLIST_INIT(&pr->pr_ips);
 224         get_mplock();
 225
 226         switch (jversion) {
 227         case 0:
 228                 /* Single IPv4 jails. */
 229                 {
 230                 struct jail_v0 jv0;
 231                 struct sockaddr_in ip4addr;
 232
 233                 error = copyin(uap->jail, &jv0, sizeof(jv0));
 234                 if (error)
 235                         goto out;
 236
 237                 j.path = jv0.path;
 238                 j.hostname = jv0.hostname;
 239
 240                 jip = kmalloc(sizeof(*jip),  M_PRISON, M_WAITOK | M_ZERO);
 241                 ip4addr.sin_family = AF_INET;
 242                 ip4addr.sin_addr.s_addr = htonl(jv0.ip_number);
 243                 memcpy(&jip->ip, &ip4addr, sizeof(ip4addr));
 244                 SLIST_INSERT_HEAD(&pr->pr_ips, jip, entries);
 245                 break;
 246                 }
 247
 248         case 1:
 249                 /*
 250                  * DragonFly multi noIP/IPv4/IPv6 jails
 251                  *
 252                  * NOTE: This version is unsupported by FreeBSD
 253                  * (which uses version 2 instead).
 254                  */
 255
 256                 error = copyin(uap->jail, &j, sizeof(j));
 257                 if (error)
 258                         goto out;
 259
 260                 for (int i = 0; i < j.n_ips; i++) {
 261                         jip = kmalloc(sizeof(*jip), M_PRISON,
 262                                       M_WAITOK | M_ZERO);
 263                         SLIST_INSERT_HEAD(&pr->pr_ips, jip, entries);
 264                         error = copyin(&j.ips[i], &jip->ip,
 265                                         sizeof(struct sockaddr_storage));
 266                         if (error)
 267                                 goto out;
 268                 }
 269                 break;
 270         default:
 271                 error = EINVAL;
 272                 goto out;
 273         }
 274
 275         error = copyinstr(j.hostname, &pr->pr_host, sizeof(pr->pr_host), 0);
 276         if (error)
 277                 goto out;
 278
 279         error = kern_jail(pr, &j);
 280         if (error)
 281                 goto out;
 282
 283         uap->sysmsg_result = pr->pr_id;
 284         rel_mplock();
 285         return (0);
 286
 287 out:
 288         /* Delete all ips */
 289         while (!SLIST_EMPTY(&pr->pr_ips)) {
 290                 jip = SLIST_FIRST(&pr->pr_ips);
 291                 SLIST_REMOVE_HEAD(&pr->pr_ips, entries);
 292                 kfree(jip, M_PRISON);
 293         }
 294         rel_mplock();
 295         kfree(pr, M_PRISON);
 296         return (error);
 297 }
 298
 299 /*
 300  * int jail_attach(int jid);
 301  *
 302  * MPALMOSTSAFE
 303  */
 304 int
 305 sys_jail_attach(struct jail_attach_args *uap)
 306 {
 307         struct thread *td = curthread;
 308         int error;
 309
 310         error = priv_check(td, PRIV_JAIL_ATTACH);
 311         if (error)
 312                 return(error);
 313         get_mplock();
 314         error = kern_jail_attach(uap->jid);
 315         rel_mplock();
 316         return (error);
 317 }
 318
 319 static void
 320 prison_ipcache_init(struct prison *pr)
 321 {
 322         struct jail_ip_storage *jis;
 323         struct sockaddr_in *ip4;
 324         struct sockaddr_in6 *ip6;
 325
 326         SLIST_FOREACH(jis, &pr->pr_ips, entries) {
 327                 switch (jis->ip.ss_family) {
 328                 case AF_INET:
 329                         ip4 = (struct sockaddr_in *)&jis->ip;
 330                         if ((ntohl(ip4->sin_addr.s_addr) >> IN_CLASSA_NSHIFT) ==
 331                             IN_LOOPBACKNET) {
 332                                 /* loopback address */
 333                                 if (pr->local_ip4 == NULL)
 334                                         pr->local_ip4 = ip4;
 335                         } else {
 336                                 /* public address */
 337                                 if (pr->nonlocal_ip4 == NULL)
 338                                         pr->nonlocal_ip4 = ip4;
 339                         }
 340                         break;
 341
 342                 case AF_INET6:
 343                         ip6 = (struct sockaddr_in6 *)&jis->ip;
 344                         if (IN6_IS_ADDR_LOOPBACK(&ip6->sin6_addr)) {
 345                                 /* loopback address */
 346                                 if (pr->local_ip6 == NULL)
 347                                         pr->local_ip6 = ip6;
 348                         } else {
 349                                 /* public address */
 350                                 if (pr->nonlocal_ip6 == NULL)
 351                                         pr->nonlocal_ip6 = ip6;
 352                         }
 353                         break;
 354                 }
 355         }
 356 }
 357
 358 /*
 359  * Changes INADDR_LOOPBACK for a valid jail address.
 360  * ip is in network byte order.
 361  * Returns 1 if the ip is among jail valid ips.
 362  * Returns 0 if is not among jail valid ips or
 363  * if couldn't replace INADDR_LOOPBACK for a valid
 364  * IP.
 365  */
 366 int
 367 prison_replace_wildcards(struct thread *td, struct sockaddr *ip)
 368 {
 369         struct sockaddr_in *ip4 = (struct sockaddr_in *)ip;
 370         struct sockaddr_in6 *ip6 = (struct sockaddr_in6 *)ip;
 371         struct prison *pr;
 372
 373         if (td->td_proc == NULL || td->td_ucred == NULL)
 374                 return (1);
 375         if ((pr = td->td_ucred->cr_prison) == NULL)
 376                 return (1);
 377
 378         if ((ip->sa_family == AF_INET &&
 379             ip4->sin_addr.s_addr == htonl(INADDR_ANY)) ||
 380             (ip->sa_family == AF_INET6 &&
 381             IN6_IS_ADDR_UNSPECIFIED(&ip6->sin6_addr)))
 382                 return (1);
 383         if ((ip->sa_family == AF_INET &&
 384             ip4->sin_addr.s_addr == htonl(INADDR_LOOPBACK)) ||
 385             (ip->sa_family == AF_INET6 &&
 386             IN6_IS_ADDR_LOOPBACK(&ip6->sin6_addr))) {
 387                 if (!prison_get_local(pr, ip->sa_family, ip) &&
 388                     !prison_get_nonlocal(pr, ip->sa_family, ip))
 389                         return(0);
 390                 else
 391                         return(1);
 392         }
 393         if (jailed_ip(pr, ip))
 394                 return(1);
 395         return(0);
 396 }
 397
 398 int
 399 prison_remote_ip(struct thread *td, struct sockaddr *ip)
 400 {
 401         struct sockaddr_in *ip4 = (struct sockaddr_in *)ip;
 402         struct sockaddr_in6 *ip6 = (struct sockaddr_in6 *)ip;
 403         struct prison *pr;
 404
 405         if (td == NULL || td->td_proc == NULL || td->td_ucred == NULL)
 406                 return(1);
 407         if ((pr = td->td_ucred->cr_prison) == NULL)
 408                 return(1);
 409         if ((ip->sa_family == AF_INET &&
 410             ip4->sin_addr.s_addr == htonl(INADDR_LOOPBACK)) ||
 411             (ip->sa_family == AF_INET6 &&
 412             IN6_IS_ADDR_LOOPBACK(&ip6->sin6_addr))) {
 413                 if (!prison_get_local(pr, ip->sa_family, ip) &&
 414                     !prison_get_nonlocal(pr, ip->sa_family, ip))
 415                         return(0);
 416                 else
 417                         return(1);
 418         }
 419         return(1);
 420 }
 421
 422 /*
 423  * Prison get non loopback ip:
 424  * - af is the address family of the ip we want (AF_INET|AF_INET6).
 425  * - If ip != NULL, put the first IP address that is not a loopback address
 426  *   into *ip.
 427  *
 428  * ip is in network by order and we don't touch it unless we find a valid ip.
 429  * No matter if ip == NULL or not, we return either a valid struct sockaddr *,
 430  * or NULL.  This struct may not be modified.
 431  */
 432 struct sockaddr *
 433 prison_get_nonlocal(struct prison *pr, sa_family_t af, struct sockaddr *ip)
 434 {
 435         struct sockaddr_in *ip4 = (struct sockaddr_in *)ip;
 436         struct sockaddr_in6 *ip6 = (struct sockaddr_in6 *)ip;
 437
 438         /* Check if it is cached */
 439         switch(af) {
 440         case AF_INET:
 441                 if (ip4 != NULL && pr->nonlocal_ip4 != NULL)
 442                         ip4->sin_addr.s_addr = pr->nonlocal_ip4->sin_addr.s_addr;
 443                 return (struct sockaddr *)pr->nonlocal_ip4;
 444
 445         case AF_INET6:
 446                 if (ip6 != NULL && pr->nonlocal_ip6 != NULL)
 447                         ip6->sin6_addr = pr->nonlocal_ip6->sin6_addr;
 448                 return (struct sockaddr *)pr->nonlocal_ip6;
 449         }
 450
 451         /* NOTREACHED */
 452         return NULL;
 453 }
 454
 455 /*
 456  * Prison get loopback ip.
 457  * - af is the address family of the ip we want (AF_INET|AF_INET6).
 458  * - If ip != NULL, put the first IP address that is not a loopback address
 459  *   into *ip.
 460  *
 461  * ip is in network by order and we don't touch it unless we find a valid ip.
 462  * No matter if ip == NULL or not, we return either a valid struct sockaddr *,
 463  * or NULL.  This struct may not be modified.
 464  */
 465 struct sockaddr *
 466 prison_get_local(struct prison *pr, sa_family_t af, struct sockaddr *ip)
 467 {
 468         struct sockaddr_in *ip4 = (struct sockaddr_in *)ip;
 469         struct sockaddr_in6 *ip6 = (struct sockaddr_in6 *)ip;
 470
 471         /* Check if it is cached */
 472         switch(af) {
 473         case AF_INET:
 474                 if (ip4 != NULL && pr->local_ip4 != NULL)
 475                         ip4->sin_addr.s_addr = pr->local_ip4->sin_addr.s_addr;
 476                 return (struct sockaddr *)pr->local_ip4;
 477
 478         case AF_INET6:
 479                 if (ip6 != NULL && pr->local_ip6 != NULL)
 480                         ip6->sin6_addr = pr->local_ip6->sin6_addr;
 481                 return (struct sockaddr *)pr->local_ip6;
 482         }
 483
 484         /* NOTREACHED */
 485         return NULL;
 486 }
 487
 488 /* Check if the IP is among ours, if it is return 1, else 0 */
 489 int
 490 jailed_ip(struct prison *pr, struct sockaddr *ip)
 491 {
 492         struct jail_ip_storage *jis;
 493         struct sockaddr_in *jip4, *ip4;
 494         struct sockaddr_in6 *jip6, *ip6;
 495
 496         if (pr == NULL)
 497                 return(0);
 498         ip4 = (struct sockaddr_in *)ip;
 499         ip6 = (struct sockaddr_in6 *)ip;
 500         SLIST_FOREACH(jis, &pr->pr_ips, entries) {
 501                 switch (ip->sa_family) {
 502                 case AF_INET:
 503                         jip4 = (struct sockaddr_in *) &jis->ip;
 504                         if (jip4->sin_family == AF_INET &&
 505                             ip4->sin_addr.s_addr == jip4->sin_addr.s_addr)
 506                                 return(1);
 507                         break;
 508                 case AF_INET6:
 509                         jip6 = (struct sockaddr_in6 *) &jis->ip;
 510                         if (jip6->sin6_family == AF_INET6 &&
 511                             IN6_ARE_ADDR_EQUAL(&ip6->sin6_addr,
 512                                                &jip6->sin6_addr))
 513                                 return(1);
 514                         break;
 515                 }
 516         }
 517         /* Ip not in list */
 518         return(0);
 519 }
 520
 521 int
 522 prison_if(struct ucred *cred, struct sockaddr *sa)
 523 {
 524         struct prison *pr;
 525         struct sockaddr_in *sai = (struct sockaddr_in*) sa;
 526
 527         pr = cred->cr_prison;
 528
 529         if (((sai->sin_family != AF_INET) && (sai->sin_family != AF_INET6))
 530             && jail_socket_unixiproute_only)
 531                 return(1);
 532         else if ((sai->sin_family != AF_INET) && (sai->sin_family != AF_INET6))
 533                 return(0);
 534         else if (jailed_ip(pr, sa))
 535                 return(0);
 536         return(1);
 537 }
 538
 539 /*
 540  * Returns a prison instance, or NULL on failure.
 541  */
 542 static struct prison *
 543 prison_find(int prid)
 544 {
 545         struct prison *pr;
 546
 547         LIST_FOREACH(pr, &allprison, pr_list) {
 548                 if (pr->pr_id == prid)
 549                         break;
 550         }
 551         return(pr);
 552 }
 553
 554 static int
 555 sysctl_jail_list(SYSCTL_HANDLER_ARGS)
 556 {
 557         struct thread *td = curthread;
 558         struct jail_ip_storage *jip;
 559 #ifdef INET6
 560         struct sockaddr_in6 *jsin6;
 561 #endif
 562         struct sockaddr_in *jsin;
 563         struct lwp *lp;
 564         struct prison *pr;
 565         unsigned int jlssize, jlsused;
 566         int count, error;
 567         char *jls; /* Jail list */
 568         char *oip; /* Output ip */
 569         char *fullpath, *freepath;
 570
 571         jlsused = 0;
 572
 573         if (jailed(td->td_ucred))
 574                 return (0);
 575         lp = td->td_lwp;
 576 retry:
 577         count = prisoncount;
 578
 579         if (count == 0)
 580                 return(0);
 581
 582         jlssize = (count * 1024);
 583         jls = kmalloc(jlssize + 1, M_TEMP, M_WAITOK | M_ZERO);
 584         if (count < prisoncount) {
 585                 kfree(jls, M_TEMP);
 586                 goto retry;
 587         }
 588         count = prisoncount;
 589
 590         LIST_FOREACH(pr, &allprison, pr_list) {
 591                 error = cache_fullpath(lp->lwp_proc, &pr->pr_root, NULL,
 592                                         &fullpath, &freepath, 0);
 593                 if (error)
 594                         continue;
 595                 if (jlsused && jlsused < jlssize)
 596                         jls[jlsused++] = '\n';
 597                 count = ksnprintf(jls + jlsused, (jlssize - jlsused),
 598                                  "%d %s %s",
 599                                  pr->pr_id, pr->pr_host, fullpath);
 600                 kfree(freepath, M_TEMP);
 601                 if (count < 0)
 602                         goto end;
 603                 jlsused += count;
 604
 605                 /* Copy the IPS */
 606                 SLIST_FOREACH(jip, &pr->pr_ips, entries) {
 607                         char buf[INET_ADDRSTRLEN];
 608
 609                         jsin = (struct sockaddr_in *)&jip->ip;
 610
 611                         switch(jsin->sin_family) {
 612                         case AF_INET:
 613                                 oip = kinet_ntoa(jsin->sin_addr, buf);
 614                                 break;
 615 #ifdef INET6
 616                         case AF_INET6:
 617                                 jsin6 = (struct sockaddr_in6 *)&jip->ip;
 618                                 oip = ip6_sprintf(&jsin6->sin6_addr);
 619                                 break;
 620 #endif
 621                         default:
 622                                 oip = "?family?";
 623                                 break;
 624                         }
 625
 626                         if ((jlssize - jlsused) < (strlen(oip) + 1)) {
 627                                 error = ERANGE;
 628                                 goto end;
 629                         }
 630                         count = ksnprintf(jls + jlsused, (jlssize - jlsused),
 631                                           " %s", oip);
 632                         if (count < 0)
 633                                 goto end;
 634                         jlsused += count;
 635                 }
 636         }
 637
 638         /*
 639          * The format is:
 640          * pr_id <SPC> hostname1 <SPC> PATH1 <SPC> IP1 <SPC> IP2\npr_id...
 641          */
 642         error = SYSCTL_OUT(req, jls, jlsused);
 643 end:
 644         kfree(jls, M_TEMP);
 645         return(error);
 646 }
 647
 648 SYSCTL_OID(_jail, OID_AUTO, list, CTLTYPE_STRING | CTLFLAG_RD, NULL, 0,
 649            sysctl_jail_list, "A", "List of active jails");
 650
 651 /*
 652  * MPSAFE
 653  */
 654 void
 655 prison_hold(struct prison *pr)
 656 {
 657         atomic_add_int(&pr->pr_ref, 1);
 658 }
 659
 660 /*
 661  * MPALMOSTSAFE
 662  */
 663 void
 664 prison_free(struct prison *pr)
 665 {
 666         struct jail_ip_storage *jls;
 667
 668         KKASSERT(pr->pr_ref > 0);
 669         if (atomic_fetchadd_int(&pr->pr_ref, -1) != 1)
 670                 return;
 671
 672         /*
 673          * The MP lock is needed on the last ref to adjust
 674          * the list.
 675          */
 676         get_mplock();
 677         if (pr->pr_ref) {
 678                 rel_mplock();
 679                 return;
 680         }
 681         LIST_REMOVE(pr, pr_list);
 682         --prisoncount;
 683         rel_mplock();
 684
 685         /*
 686          * Clean up
 687          */
 688         while (!SLIST_EMPTY(&pr->pr_ips)) {
 689                 jls = SLIST_FIRST(&pr->pr_ips);
 690                 SLIST_REMOVE_HEAD(&pr->pr_ips, entries);
 691                 kfree(jls, M_PRISON);
 692         }
 693
 694         if (pr->pr_linux != NULL)
 695                 kfree(pr->pr_linux, M_PRISON);
 696         varsymset_clean(&pr->pr_varsymset);
 697         cache_drop(&pr->pr_root);
 698         kfree(pr, M_PRISON);
 699 }
 700
 701 /*
 702  * Check if permisson for a specific privilege is granted within jail.
 703  *
 704  * MPSAFE
 705  */
 706 int
 707 prison_priv_check(struct ucred *cred, int priv)
 708 {
 709         if (!jailed(cred))
 710                 return (0);
 711
 712         switch (priv) {
 713         case PRIV_CRED_SETUID:
 714         case PRIV_CRED_SETEUID:
 715         case PRIV_CRED_SETGID:
 716         case PRIV_CRED_SETEGID:
 717         case PRIV_CRED_SETGROUPS:
 718         case PRIV_CRED_SETREUID:
 719         case PRIV_CRED_SETREGID:
 720         case PRIV_CRED_SETRESUID:
 721         case PRIV_CRED_SETRESGID:
 722
 723         case PRIV_VFS_SYSFLAGS:
 724         case PRIV_VFS_CHOWN:
 725         case PRIV_VFS_CHMOD:
 726         case PRIV_VFS_CHROOT:
 727         case PRIV_VFS_LINK:
 728         case PRIV_VFS_CHFLAGS_DEV:
 729         case PRIV_VFS_REVOKE:
 730         case PRIV_VFS_MKNOD_BAD:
 731         case PRIV_VFS_MKNOD_WHT:
 732         case PRIV_VFS_MKNOD_DIR:
 733         case PRIV_VFS_SETATTR:
 734         case PRIV_VFS_SETGID:
 735
 736         case PRIV_PROC_SETRLIMIT:
 737         case PRIV_PROC_SETLOGIN:
 738
 739         case PRIV_SYSCTL_WRITEJAIL:
 740
 741         case PRIV_VARSYM_SYS:
 742
 743         case PRIV_SETHOSTNAME:
 744
 745         case PRIV_PROC_TRESPASS:
 746
 747                 return (0);
 748
 749         case PRIV_UFS_QUOTAON:
 750         case PRIV_UFS_QUOTAOFF:
 751         case PRIV_VFS_SETQUOTA:
 752         case PRIV_UFS_SETUSE:
 753         case PRIV_VFS_GETQUOTA:
 754                 return (0);
 755
 756
 757         case PRIV_DEBUG_UNPRIV:
 758                 return (0);
 759
 760
 761                 /*
 762                  * Allow jailed root to bind reserved ports.
 763                  */
 764         case PRIV_NETINET_RESERVEDPORT:
 765                 return (0);
 766
 767
 768                 /*
 769                  * Conditionally allow creating raw sockets in jail.
 770                  */
 771         case PRIV_NETINET_RAW:
 772                 if (jail_allow_raw_sockets)
 773                         return (0);
 774                 else
 775                         return (EPERM);
 776
 777         case PRIV_HAMMER_IOCTL:
 778                 return (0);
 779
 780         default:
 781
 782                 return (EPERM);
 783         }
 784 }