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