usr.sbin/jail/command.c

   1 /*-
   2  * Copyright (c) 2011 James Gritton
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 #include <sys/cdefs.h>
  28 __FBSDID("$FreeBSD$");
  29
  30 #include <sys/types.h>
  31 #include <sys/event.h>
  32 #include <sys/mount.h>
  33 #include <sys/stat.h>
  34 #include <sys/sysctl.h>
  35 #include <sys/user.h>
  36 #include <sys/wait.h>
  37
  38 #include <err.h>
  39 #include <errno.h>
  40 #include <fcntl.h>
  41 #include <kvm.h>
  42 #include <login_cap.h>
  43 #include <paths.h>
  44 #include <pwd.h>
  45 #include <signal.h>
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <string.h>
  49 #include <unistd.h>
  50
  51 #include "jailp.h"
  52
  53 #define DEFAULT_STOP_TIMEOUT    10
  54 #define PHASH_SIZE              256
  55
  56 LIST_HEAD(phhead, phash);
  57
  58 struct phash {
  59         LIST_ENTRY(phash)       le;
  60         struct cfjail           *j;
  61         pid_t                   pid;
  62 };
  63
  64 int paralimit = -1;
  65
  66 extern char **environ;
  67
  68 static int run_command(struct cfjail *j);
  69 static int add_proc(struct cfjail *j, pid_t pid);
  70 static void clear_procs(struct cfjail *j);
  71 static struct cfjail *find_proc(pid_t pid);
  72 static int term_procs(struct cfjail *j);
  73 static int get_user_info(struct cfjail *j, const char *username,
  74     const struct passwd **pwdp, login_cap_t **lcapp);
  75 static int check_path(struct cfjail *j, const char *pname, const char *path,
  76     int isfile, const char *umount_type);
  77
  78 static struct cfjails sleeping = TAILQ_HEAD_INITIALIZER(sleeping);
  79 static struct cfjails runnable = TAILQ_HEAD_INITIALIZER(runnable);
  80 static struct cfstring dummystring = { .len = 1 };
  81 static struct phhead phash[PHASH_SIZE];
  82 static int kq;
  83
  84 /*
  85  * Run the next command associated with a jail.
  86  */
  87 int
  88 next_command(struct cfjail *j)
  89 {
  90         enum intparam comparam;
  91         int create_failed, stopping;
  92
  93         if (paralimit == 0) {
  94                 requeue(j, &runnable);
  95                 return 1;
  96         }
  97         create_failed = (j->flags & (JF_STOP | JF_FAILED)) == JF_FAILED;
  98         stopping = (j->flags & JF_STOP) != 0;
  99         comparam = *j->comparam;
 100         for (;;) {
 101                 if (j->comstring == NULL) {
 102                         j->comparam += create_failed ? -1 : 1;
 103                         switch ((comparam = *j->comparam)) {
 104                         case IP__NULL:
 105                                 return 0;
 106                         case IP_MOUNT_DEVFS:
 107                                 if (!bool_param(j->intparams[IP_MOUNT_DEVFS]))
 108                                         continue;
 109                                 j->comstring = &dummystring;
 110                                 break;
 111                         case IP_MOUNT_FDESCFS:
 112                                 if (!bool_param(j->intparams[IP_MOUNT_FDESCFS]))
 113                                         continue;
 114                                 j->comstring = &dummystring;
 115                         case IP__OP:
 116                         case IP_STOP_TIMEOUT:
 117                                 j->comstring = &dummystring;
 118                                 break;
 119                         default:
 120                                 if (j->intparams[comparam] == NULL)
 121                                         continue;
 122                                 j->comstring = create_failed || (stopping &&
 123                                     (j->intparams[comparam]->flags & PF_REV))
 124                                     ? TAILQ_LAST(&j->intparams[comparam]->val,
 125                                         cfstrings)
 126                                     : TAILQ_FIRST(&j->intparams[comparam]->val);
 127                         }
 128                 } else {
 129                         j->comstring = j->comstring == &dummystring ? NULL :
 130                             create_failed || (stopping &&
 131                             (j->intparams[comparam]->flags & PF_REV))
 132                             ? TAILQ_PREV(j->comstring, cfstrings, tq)
 133                             : TAILQ_NEXT(j->comstring, tq);
 134                 }
 135                 if (j->comstring == NULL || j->comstring->len == 0 ||
 136                     (create_failed && (comparam == IP_EXEC_PRESTART ||
 137                     comparam == IP_EXEC_START || comparam == IP_COMMAND ||
 138                     comparam == IP_EXEC_POSTSTART)))
 139                         continue;
 140                 switch (run_command(j)) {
 141                 case -1:
 142                         failed(j);
 143                         /* FALLTHROUGH */
 144                 case 1:
 145                         return 1;
 146                 }
 147         }
 148 }
 149
 150 /*
 151  * Check command exit status
 152  */
 153 int
 154 finish_command(struct cfjail *j)
 155 {
 156         int error;
 157
 158         if (!(j->flags & JF_SLEEPQ))
 159                 return 0;
 160         j->flags &= ~JF_SLEEPQ;
 161         if (*j->comparam == IP_STOP_TIMEOUT)
 162         {
 163                 j->flags &= ~JF_TIMEOUT;
 164                 j->pstatus = 0;
 165                 return 0;
 166         }
 167         paralimit++;
 168         if (!TAILQ_EMPTY(&runnable))
 169                 requeue(TAILQ_FIRST(&runnable), &ready);
 170         error = 0;
 171         if (j->flags & JF_TIMEOUT) {
 172                 j->flags &= ~JF_TIMEOUT;
 173                 if (*j->comparam != IP_STOP_TIMEOUT) {
 174                         jail_warnx(j, "%s: timed out", j->comline);
 175                         failed(j);
 176                         error = -1;
 177                 } else if (verbose > 0)
 178                         jail_note(j, "timed out\n");
 179         } else if (j->pstatus != 0) {
 180                 if (WIFSIGNALED(j->pstatus))
 181                         jail_warnx(j, "%s: exited on signal %d",
 182                             j->comline, WTERMSIG(j->pstatus));
 183                 else
 184                         jail_warnx(j, "%s: failed", j->comline);
 185                 j->pstatus = 0;
 186                 failed(j);
 187                 error = -1;
 188         }
 189         free(j->comline);
 190         j->comline = NULL;
 191         return error;
 192 }
 193
 194 /*
 195  * Check for finished processes or timeouts.
 196  */
 197 struct cfjail *
 198 next_proc(int nonblock)
 199 {
 200         struct kevent ke;
 201         struct timespec ts;
 202         struct timespec *tsp;
 203         struct cfjail *j;
 204
 205         if (!TAILQ_EMPTY(&sleeping)) {
 206         again:
 207                 tsp = NULL;
 208                 if ((j = TAILQ_FIRST(&sleeping)) && j->timeout.tv_sec) {
 209                         clock_gettime(CLOCK_REALTIME, &ts);
 210                         ts.tv_sec = j->timeout.tv_sec - ts.tv_sec;
 211                         ts.tv_nsec = j->timeout.tv_nsec - ts.tv_nsec;
 212                         if (ts.tv_nsec < 0) {
 213                                 ts.tv_sec--;
 214                                 ts.tv_nsec += 1000000000;
 215                         }
 216                         if (ts.tv_sec < 0 ||
 217                             (ts.tv_sec == 0 && ts.tv_nsec == 0)) {
 218                                 j->flags |= JF_TIMEOUT;
 219                                 clear_procs(j);
 220                                 return j;
 221                         }
 222                         tsp = &ts;
 223                 }
 224                 if (nonblock) {
 225                         ts.tv_sec = 0;
 226                         ts.tv_nsec = 0;
 227                         tsp = &ts;
 228                 }
 229                 switch (kevent(kq, NULL, 0, &ke, 1, tsp)) {
 230                 case -1:
 231                         if (errno != EINTR)
 232                                 err(1, "kevent");
 233                         goto again;
 234                 case 0:
 235                         if (!nonblock) {
 236                                 j = TAILQ_FIRST(&sleeping);
 237                                 j->flags |= JF_TIMEOUT;
 238                                 clear_procs(j);
 239                                 return j;
 240                         }
 241                         break;
 242                 case 1:
 243                         (void)waitpid(ke.ident, NULL, WNOHANG);
 244                         if ((j = find_proc(ke.ident))) {
 245                                 j->pstatus = ke.data;
 246                                 return j;
 247                         }
 248                         goto again;
 249                 }
 250         }
 251         return NULL;
 252 }
 253
 254 /*
 255  * Run a single command for a jail, possible inside the jail.
 256  */
 257 static int
 258 run_command(struct cfjail *j)
 259 {
 260         const struct passwd *pwd;
 261         const struct cfstring *comstring, *s;
 262         login_cap_t *lcap;
 263         char **argv;
 264         char *cs, *comcs, *devpath;
 265         const char *jidstr, *conslog, *path, *ruleset, *term, *username;
 266         enum intparam comparam;
 267         size_t comlen;
 268         pid_t pid;
 269         int argc, bg, clean, consfd, down, fib, i, injail, sjuser, timeout;
 270 #if defined(INET) || defined(INET6)
 271         char *addr;
 272 #endif
 273
 274         static char *cleanenv;
 275
 276         /* Perform some operations that aren't actually commands */
 277         comparam = *j->comparam;
 278         down = j->flags & (JF_STOP | JF_FAILED);
 279         switch (comparam) {
 280         case IP_STOP_TIMEOUT:
 281                 return term_procs(j);
 282
 283         case IP__OP:
 284                 if (down) {
 285                         if (jail_remove(j->jid) < 0 && errno == EPERM) {
 286                                 jail_warnx(j, "jail_remove: %s",
 287                                            strerror(errno));
 288                                 return -1;
 289                         }
 290                         if (verbose > 0 || (verbose == 0 && (j->flags & JF_STOP
 291                             ? note_remove : j->name != NULL)))
 292                             jail_note(j, "removed\n");
 293                         j->jid = -1;
 294                         if (j->flags & JF_STOP)
 295                                 dep_done(j, DF_LIGHT);
 296                         else
 297                                 j->flags &= ~JF_PERSIST;
 298                 } else {
 299                         if (create_jail(j) < 0)
 300                                 return -1;
 301                         if (iflag)
 302                                 printf("%d\n", j->jid);
 303                         if (verbose >= 0 && (j->name || verbose > 0))
 304                                 jail_note(j, "created\n");
 305                         dep_done(j, DF_LIGHT);
 306                 }
 307                 return 0;
 308
 309         default: ;
 310         }
 311         /*
 312          * Collect exec arguments.  Internal commands for network and
 313          * mounting build their own argument lists.
 314          */
 315         comstring = j->comstring;
 316         bg = 0;
 317         switch (comparam) {
 318 #ifdef INET
 319         case IP__IP4_IFADDR:
 320                 argv = alloca(8 * sizeof(char *));
 321                 *(const char **)&argv[0] = _PATH_IFCONFIG;
 322                 if ((cs = strchr(comstring->s, '|'))) {
 323                         argv[1] = alloca(cs - comstring->s + 1);
 324                         strlcpy(argv[1], comstring->s, cs - comstring->s + 1);
 325                         addr = cs + 1;
 326                 } else {
 327                         *(const char **)&argv[1] =
 328                             string_param(j->intparams[IP_INTERFACE]);
 329                         addr = comstring->s;
 330                 }
 331                 *(const char **)&argv[2] = "inet";
 332                 if (!(cs = strchr(addr, '/'))) {
 333                         argv[3] = addr;
 334                         *(const char **)&argv[4] = "netmask";
 335                         *(const char **)&argv[5] = "255.255.255.255";
 336                         argc = 6;
 337                 } else if (strchr(cs + 1, '.')) {
 338                         argv[3] = alloca(cs - addr + 1);
 339                         strlcpy(argv[3], addr, cs - addr + 1);
 340                         *(const char **)&argv[4] = "netmask";
 341                         *(const char **)&argv[5] = cs + 1;
 342                         argc = 6;
 343                 } else {
 344                         argv[3] = addr;
 345                         argc = 4;
 346                 }
 347                 *(const char **)&argv[argc] = down ? "-alias" : "alias";
 348                 argv[argc + 1] = NULL;
 349                 break;
 350 #endif
 351
 352 #ifdef INET6
 353         case IP__IP6_IFADDR:
 354                 argv = alloca(8 * sizeof(char *));
 355                 *(const char **)&argv[0] = _PATH_IFCONFIG;
 356                 if ((cs = strchr(comstring->s, '|'))) {
 357                         argv[1] = alloca(cs - comstring->s + 1);
 358                         strlcpy(argv[1], comstring->s, cs - comstring->s + 1);
 359                         addr = cs + 1;
 360                 } else {
 361                         *(const char **)&argv[1] =
 362                             string_param(j->intparams[IP_INTERFACE]);
 363                         addr = comstring->s;
 364                 }
 365                 *(const char **)&argv[2] = "inet6";
 366                 argv[3] = addr;
 367                 if (!(cs = strchr(addr, '/'))) {
 368                         *(const char **)&argv[4] = "prefixlen";
 369                         *(const char **)&argv[5] = "128";
 370                         argc = 6;
 371                 } else
 372                         argc = 4;
 373                 *(const char **)&argv[argc] = down ? "-alias" : "alias";
 374                 argv[argc + 1] = NULL;
 375                 break;
 376 #endif
 377
 378         case IP_VNET_INTERFACE:
 379                 argv = alloca(5 * sizeof(char *));
 380                 *(const char **)&argv[0] = _PATH_IFCONFIG;
 381                 argv[1] = comstring->s;
 382                 *(const char **)&argv[2] = down ? "-vnet" : "vnet";
 383                 jidstr = string_param(j->intparams[KP_JID]);
 384                 *(const char **)&argv[3] =
 385                         jidstr ? jidstr : string_param(j->intparams[KP_NAME]);
 386                 argv[4] = NULL;
 387                 break;
 388
 389         case IP_MOUNT:
 390         case IP__MOUNT_FROM_FSTAB:
 391                 argv = alloca(8 * sizeof(char *));
 392                 comcs = alloca(comstring->len + 1);
 393                 strcpy(comcs, comstring->s);
 394                 argc = 0;
 395                 for (cs = strtok(comcs, " \t\f\v\r\n"); cs && argc < 4;
 396                      cs = strtok(NULL, " \t\f\v\r\n"))
 397                         argv[argc++] = cs;
 398                 if (argc == 0)
 399                         return 0;
 400                 if (argc < 3) {
 401                         jail_warnx(j, "%s: %s: missing information",
 402                             j->intparams[comparam]->name, comstring->s);
 403                         return -1;
 404                 }
 405                 if (check_path(j, j->intparams[comparam]->name, argv[1], 0,
 406                     down ? argv[2] : NULL) < 0)
 407                         return -1;
 408                 if (down) {
 409                         argv[4] = NULL;
 410                         argv[3] = argv[1];
 411                         *(const char **)&argv[0] = "/sbin/umount";
 412                 } else {
 413                         if (argc == 4) {
 414                                 argv[7] = NULL;
 415                                 argv[6] = argv[1];
 416                                 argv[5] = argv[0];
 417                                 argv[4] = argv[3];
 418                                 *(const char **)&argv[3] = "-o";
 419                         } else {
 420                                 argv[5] = NULL;
 421                                 argv[4] = argv[1];
 422                                 argv[3] = argv[0];
 423                         }
 424                         *(const char **)&argv[0] = _PATH_MOUNT;
 425                 }
 426                 *(const char **)&argv[1] = "-t";
 427                 break;
 428
 429         case IP_MOUNT_DEVFS:
 430                 argv = alloca(7 * sizeof(char *));
 431                 path = string_param(j->intparams[KP_PATH]);
 432                 if (path == NULL) {
 433                         jail_warnx(j, "mount.devfs: no path");
 434                         return -1;
 435                 }
 436                 devpath = alloca(strlen(path) + 5);
 437                 sprintf(devpath, "%s/dev", path);
 438                 if (check_path(j, "mount.devfs", devpath, 0,
 439                     down ? "devfs" : NULL) < 0)
 440                         return -1;
 441                 if (down) {
 442                         *(const char **)&argv[0] = "/sbin/umount";
 443                         argv[1] = devpath;
 444                         argv[2] = NULL;
 445                 } else {
 446                         *(const char **)&argv[0] = _PATH_MOUNT;
 447                         *(const char **)&argv[1] = "-t";
 448                         *(const char **)&argv[2] = "devfs";
 449                         ruleset = string_param(j->intparams[KP_DEVFS_RULESET]);
 450                         if (!ruleset)
 451                             ruleset = "4";      /* devfsrules_jail */
 452                         argv[3] = alloca(11 + strlen(ruleset));
 453                         sprintf(argv[3], "-oruleset=%s", ruleset);
 454                         *(const char **)&argv[4] = ".";
 455                         argv[5] = devpath;
 456                         argv[6] = NULL;
 457                 }
 458                 break;
 459
 460         case IP_MOUNT_FDESCFS:
 461                 argv = alloca(7 * sizeof(char *));
 462                 path = string_param(j->intparams[KP_PATH]);
 463                 if (path == NULL) {
 464                         jail_warnx(j, "mount.fdescfs: no path");
 465                         return -1;
 466                 }
 467                 devpath = alloca(strlen(path) + 8);
 468                 sprintf(devpath, "%s/dev/fd", path);
 469                 if (check_path(j, "mount.fdescfs", devpath, 0,
 470                     down ? "fdescfs" : NULL) < 0)
 471                         return -1;
 472                 if (down) {
 473                         *(const char **)&argv[0] = "/sbin/umount";
 474                         argv[1] = devpath;
 475                         argv[2] = NULL;
 476                 } else {
 477                         *(const char **)&argv[0] = _PATH_MOUNT;
 478                         *(const char **)&argv[1] = "-t";
 479                         *(const char **)&argv[2] = "fdescfs";
 480                         *(const char **)&argv[3] = ".";
 481                         argv[4] = devpath;
 482                         argv[5] = NULL;
 483                 }
 484                 break;
 485
 486         case IP_COMMAND:
 487                 if (j->name != NULL)
 488                         goto default_command;
 489                 argc = 0;
 490                 TAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq)
 491                         argc++;
 492                 argv = alloca((argc + 1) * sizeof(char *));
 493                 argc = 0;
 494                 TAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq)
 495                         argv[argc++] = s->s;
 496                 argv[argc] = NULL;
 497                 j->comstring = &dummystring;
 498                 break;
 499
 500         default:
 501         default_command:
 502                 if ((cs = strpbrk(comstring->s, "!\"$&'()*;<>?[\\]`{|}~")) &&
 503                     !(cs[0] == '&' && cs[1] == '\0')) {
 504                         argv = alloca(4 * sizeof(char *));
 505                         *(const char **)&argv[0] = _PATH_BSHELL;
 506                         *(const char **)&argv[1] = "-c";
 507                         argv[2] = comstring->s;
 508                         argv[3] = NULL;
 509                 } else {
 510                         if (cs) {
 511                                 *cs = 0;
 512                                 bg = 1;
 513                         }
 514                         comcs = alloca(comstring->len + 1);
 515                         strcpy(comcs, comstring->s);
 516                         argc = 0;
 517                         for (cs = strtok(comcs, " \t\f\v\r\n"); cs;
 518                              cs = strtok(NULL, " \t\f\v\r\n"))
 519                                 argc++;
 520                         argv = alloca((argc + 1) * sizeof(char *));
 521                         strcpy(comcs, comstring->s);
 522                         argc = 0;
 523                         for (cs = strtok(comcs, " \t\f\v\r\n"); cs;
 524                              cs = strtok(NULL, " \t\f\v\r\n"))
 525                                 argv[argc++] = cs;
 526                         argv[argc] = NULL;
 527                 }
 528         }
 529         if (argv[0] == NULL)
 530                 return 0;
 531
 532         if (int_param(j->intparams[IP_EXEC_TIMEOUT], &timeout) &&
 533             timeout != 0) {
 534                 clock_gettime(CLOCK_REALTIME, &j->timeout);
 535                 j->timeout.tv_sec += timeout;
 536         } else
 537                 j->timeout.tv_sec = 0;
 538
 539         injail = comparam == IP_EXEC_START || comparam == IP_COMMAND ||
 540             comparam == IP_EXEC_STOP;
 541         clean = bool_param(j->intparams[IP_EXEC_CLEAN]);
 542         username = string_param(j->intparams[injail
 543             ? IP_EXEC_JAIL_USER : IP_EXEC_SYSTEM_USER]);
 544         sjuser = bool_param(j->intparams[IP_EXEC_SYSTEM_JAIL_USER]);
 545
 546         consfd = 0;
 547         if (injail &&
 548             (conslog = string_param(j->intparams[IP_EXEC_CONSOLELOG]))) {
 549                 if (check_path(j, "exec.consolelog", conslog, 1, NULL) < 0)
 550                         return -1;
 551                 consfd =
 552                     open(conslog, O_WRONLY | O_CREAT | O_APPEND, DEFFILEMODE);
 553                 if (consfd < 0) {
 554                         jail_warnx(j, "open %s: %s", conslog, strerror(errno));
 555                         return -1;
 556                 }
 557         }
 558
 559         comlen = 0;
 560         for (i = 0; argv[i]; i++)
 561                 comlen += strlen(argv[i]) + 1;
 562         j->comline = cs = emalloc(comlen);
 563         for (i = 0; argv[i]; i++) {
 564                 strcpy(cs, argv[i]);
 565                 if (argv[i + 1]) {
 566                         cs += strlen(argv[i]) + 1;
 567                         cs[-1] = ' ';
 568                 }
 569         }
 570         if (verbose > 0)
 571                 jail_note(j, "run command%s%s%s: %s\n",
 572                     injail ? " in jail" : "", username ? " as " : "",
 573                     username ? username : "", j->comline);
 574
 575         pid = fork();
 576         if (pid < 0)
 577                 err(1, "fork");
 578         if (pid > 0) {
 579                 if (bg || !add_proc(j, pid)) {
 580                         free(j->comline);
 581                         j->comline = NULL;
 582                         return 0;
 583                 } else {
 584                         paralimit--;
 585                         return 1;
 586                 }
 587         }
 588         if (bg)
 589                 setsid();
 590
 591         /* Set up the environment and run the command */
 592         pwd = NULL;
 593         lcap = NULL;
 594         if ((clean || username) && injail && sjuser &&
 595             get_user_info(j, username, &pwd, &lcap) < 0)
 596                 exit(1);
 597         if (injail) {
 598                 /* jail_attach won't chdir along with its chroot. */
 599                 path = string_param(j->intparams[KP_PATH]);
 600                 if (path && chdir(path) < 0) {
 601                         jail_warnx(j, "chdir %s: %s", path, strerror(errno));
 602                         exit(1);
 603                 }
 604                 if (int_param(j->intparams[IP_EXEC_FIB], &fib) &&
 605                     setfib(fib) < 0) {
 606                         jail_warnx(j, "setfib: %s", strerror(errno));
 607                         exit(1);
 608                 }
 609                 if (jail_attach(j->jid) < 0) {
 610                         jail_warnx(j, "jail_attach: %s", strerror(errno));
 611                         exit(1);
 612                 }
 613         }
 614         if (clean || username) {
 615                 if (!(injail && sjuser) &&
 616                     get_user_info(j, username, &pwd, &lcap) < 0)
 617                         exit(1);
 618                 if (clean) {
 619                         term = getenv("TERM");
 620                         environ = &cleanenv;
 621                         setenv("PATH", "/bin:/usr/bin", 0);
 622                         if (term != NULL)
 623                                 setenv("TERM", term, 1);
 624                 }
 625                 if (setusercontext(lcap, pwd, pwd->pw_uid, username
 626                     ? LOGIN_SETALL & ~LOGIN_SETGROUP & ~LOGIN_SETLOGIN
 627                     : LOGIN_SETPATH | LOGIN_SETENV) < 0) {
 628                         jail_warnx(j, "setusercontext %s: %s", pwd->pw_name,
 629                             strerror(errno));
 630                         exit(1);
 631                 }
 632                 login_close(lcap);
 633                 setenv("USER", pwd->pw_name, 1);
 634                 setenv("HOME", pwd->pw_dir, 1);
 635                 setenv("SHELL",
 636                     *pwd->pw_shell ? pwd->pw_shell : _PATH_BSHELL, 1);
 637                 if (clean && chdir(pwd->pw_dir) < 0) {
 638                         jail_warnx(j, "chdir %s: %s",
 639                             pwd->pw_dir, strerror(errno));
 640                         exit(1);
 641                 }
 642                 endpwent();
 643         }
 644
 645         if (consfd != 0 && (dup2(consfd, 1) < 0 || dup2(consfd, 2) < 0)) {
 646                 jail_warnx(j, "exec.consolelog: %s", strerror(errno));
 647                 exit(1);
 648         }
 649         closefrom(3);
 650         execvp(argv[0], argv);
 651         jail_warnx(j, "exec %s: %s", argv[0], strerror(errno));
 652         exit(1);
 653 }
 654
 655 /*
 656  * Add a process to the hash, tied to a jail.
 657  */
 658 static int
 659 add_proc(struct cfjail *j, pid_t pid)
 660 {
 661         struct kevent ke;
 662         struct cfjail *tj;
 663         struct phash *ph;
 664
 665         if (!kq && (kq = kqueue()) < 0)
 666                 err(1, "kqueue");
 667         EV_SET(&ke, pid, EVFILT_PROC, EV_ADD, NOTE_EXIT, 0, NULL);
 668         if (kevent(kq, &ke, 1, NULL, 0, NULL) < 0) {
 669                 if (errno == ESRCH)
 670                         return 0;
 671                 err(1, "kevent");
 672         }
 673         ph = emalloc(sizeof(struct phash));
 674         ph->j = j;
 675         ph->pid = pid;
 676         LIST_INSERT_HEAD(&phash[pid % PHASH_SIZE], ph, le);
 677         j->nprocs++;
 678         j->flags |= JF_SLEEPQ;
 679         if (j->timeout.tv_sec == 0)
 680                 requeue(j, &sleeping);
 681         else {
 682                 /* File the jail in the sleep queue acording to its timeout. */
 683                 TAILQ_REMOVE(j->queue, j, tq);
 684                 TAILQ_FOREACH(tj, &sleeping, tq) {
 685                         if (!tj->timeout.tv_sec ||
 686                             j->timeout.tv_sec < tj->timeout.tv_sec ||
 687                             (j->timeout.tv_sec == tj->timeout.tv_sec &&
 688                             j->timeout.tv_nsec <= tj->timeout.tv_nsec)) {
 689                                 TAILQ_INSERT_BEFORE(tj, j, tq);
 690                                 break;
 691                         }
 692                 }
 693                 if (tj == NULL)
 694                         TAILQ_INSERT_TAIL(&sleeping, j, tq);
 695                 j->queue = &sleeping;
 696         }
 697         return 1;
 698 }
 699
 700 /*
 701  * Remove any processes from the hash that correspond to a jail.
 702  */
 703 static void
 704 clear_procs(struct cfjail *j)
 705 {
 706         struct kevent ke;
 707         struct phash *ph, *tph;
 708         int i;
 709
 710         j->nprocs = 0;
 711         for (i = 0; i < PHASH_SIZE; i++)
 712                 LIST_FOREACH_SAFE(ph, &phash[i], le, tph)
 713                         if (ph->j == j) {
 714                                 EV_SET(&ke, ph->pid, EVFILT_PROC, EV_DELETE,
 715                                     NOTE_EXIT, 0, NULL);
 716                                 (void)kevent(kq, &ke, 1, NULL, 0, NULL);
 717                                 LIST_REMOVE(ph, le);
 718                                 free(ph);
 719                         }
 720 }
 721
 722 /*
 723  * Find the jail that corresponds to an exited process.
 724  */
 725 static struct cfjail *
 726 find_proc(pid_t pid)
 727 {
 728         struct cfjail *j;
 729         struct phash *ph;
 730
 731         LIST_FOREACH(ph, &phash[pid % PHASH_SIZE], le)
 732                 if (ph->pid == pid) {
 733                         j = ph->j;
 734                         LIST_REMOVE(ph, le);
 735                         free(ph);
 736                         return --j->nprocs ? NULL : j;
 737                 }
 738         return NULL;
 739 }
 740
 741 /*
 742  * Send SIGTERM to all processes in a jail and wait for them to die.
 743  */
 744 static int
 745 term_procs(struct cfjail *j)
 746 {
 747         struct kinfo_proc *ki;
 748         int i, noted, pcnt, timeout;
 749
 750         static kvm_t *kd;
 751
 752         if (!int_param(j->intparams[IP_STOP_TIMEOUT], &timeout))
 753                 timeout = DEFAULT_STOP_TIMEOUT;
 754         else if (timeout == 0)
 755                 return 0;
 756
 757         if (kd == NULL) {
 758                 kd = kvm_open(NULL, NULL, NULL, O_RDONLY, NULL);
 759                 if (kd == NULL)
 760                         return 0;
 761         }
 762
 763         ki = kvm_getprocs(kd, KERN_PROC_PROC, 0, &pcnt);
 764         if (ki == NULL)
 765                 return 0;
 766         noted = 0;
 767         for (i = 0; i < pcnt; i++)
 768                 if (ki[i].ki_jid == j->jid &&
 769                     kill(ki[i].ki_pid, SIGTERM) == 0) {
 770                         (void)add_proc(j, ki[i].ki_pid);
 771                         if (verbose > 0) {
 772                                 if (!noted) {
 773                                         noted = 1;
 774                                         jail_note(j, "sent SIGTERM to:");
 775                                 }
 776                                 printf(" %d", ki[i].ki_pid);
 777                         }
 778                 }
 779         if (noted)
 780                 printf("\n");
 781         if (j->nprocs > 0) {
 782                 clock_gettime(CLOCK_REALTIME, &j->timeout);
 783                 j->timeout.tv_sec += timeout;
 784                 return 1;
 785         }
 786         return 0;
 787 }
 788
 789 /*
 790  * Look up a user in the passwd and login.conf files.
 791  */
 792 static int
 793 get_user_info(struct cfjail *j, const char *username,
 794     const struct passwd **pwdp, login_cap_t **lcapp)
 795 {
 796         const struct passwd *pwd;
 797
 798         *pwdp = pwd = username ? getpwnam(username) : getpwuid(getuid());
 799         if (pwd == NULL) {
 800                 if (errno)
 801                         jail_warnx(j, "getpwnam%s%s: %s", username ? " " : "",
 802                             username ? username : "", strerror(errno));
 803                 else if (username)
 804                         jail_warnx(j, "%s: no such user", username);
 805                 else
 806                         jail_warnx(j, "unknown uid %d", getuid());
 807                 return -1;
 808         }
 809         *lcapp = login_getpwclass(pwd);
 810         if (*lcapp == NULL) {
 811                 jail_warnx(j, "getpwclass %s: %s", pwd->pw_name,
 812                     strerror(errno));
 813                 return -1;
 814         }
 815         /* Set the groups while the group file is still available */
 816         if (initgroups(pwd->pw_name, pwd->pw_gid) < 0) {
 817                 jail_warnx(j, "initgroups %s: %s", pwd->pw_name,
 818                     strerror(errno));
 819                 return -1;
 820         }
 821         return 0;
 822 }
 823
 824 /*
 825  * Make sure a mount or consolelog path is a valid absolute pathname
 826  * with no symlinks.
 827  */
 828 static int
 829 check_path(struct cfjail *j, const char *pname, const char *path, int isfile,
 830     const char *umount_type)
 831 {
 832         struct stat st, mpst;
 833         struct statfs stfs;
 834         char *tpath, *p;
 835         const char *jailpath;
 836         size_t jplen;
 837
 838         if (path[0] != '/') {
 839                 jail_warnx(j, "%s: %s: not an absolute pathname",
 840                     pname, path);
 841                 return -1;
 842         }
 843         /*
 844          * Only check for symlinks in components below the jail's path,
 845          * since that's where the security risk lies.
 846          */
 847         jailpath = string_param(j->intparams[KP_PATH]);
 848         if (jailpath == NULL)
 849                 jailpath = "";
 850         jplen = strlen(jailpath);
 851         if (!strncmp(path, jailpath, jplen) && path[jplen] == '/') {
 852                 tpath = alloca(strlen(path) + 1);
 853                 strcpy(tpath, path);
 854                 for (p = tpath + jplen; p != NULL; ) {
 855                         p = strchr(p + 1, '/');
 856                         if (p)
 857                                 *p = '\0';
 858                         if (lstat(tpath, &st) < 0) {
 859                                 if (errno == ENOENT && isfile && !p)
 860                                         break;
 861                                 jail_warnx(j, "%s: %s: %s", pname, tpath,
 862                                     strerror(errno));
 863                                 return -1;
 864                         }
 865                         if (S_ISLNK(st.st_mode)) {
 866                                 jail_warnx(j, "%s: %s is a symbolic link",
 867                                     pname, tpath);
 868                                 return -1;
 869                         }
 870                         if (p)
 871                                 *p = '/';
 872                 }
 873         }
 874         if (umount_type != NULL) {
 875                 if (stat(path, &st) < 0 || statfs(path, &stfs) < 0) {
 876                         jail_warnx(j, "%s: %s: %s", pname, path,
 877                             strerror(errno));
 878                         return -1;
 879                 }
 880                 if (stat(stfs.f_mntonname, &mpst) < 0) {
 881                         jail_warnx(j, "%s: %s: %s", pname, stfs.f_mntonname,
 882                             strerror(errno));
 883                         return -1;
 884                 }
 885                 if (st.st_ino != mpst.st_ino) {
 886                         jail_warnx(j, "%s: %s: not a mount point",
 887                             pname, path);
 888                         return -1;
 889                 }
 890                 if (strcmp(stfs.f_fstypename, umount_type)) {
 891                         jail_warnx(j, "%s: %s: not a %s mount",
 892                             pname, path, umount_type);
 893                         return -1;
 894                 }
 895         }
 896         return 0;
 897 }