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