src/execute.c

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <assert.h>
  23 #include <dirent.h>
  24 #include <errno.h>
  25 #include <fcntl.h>
  26 #include <unistd.h>
  27 #include <string.h>
  28 #include <signal.h>
  29 #include <sys/socket.h>
  30 #include <sys/un.h>
  31 #include <sys/prctl.h>
  32 #include <linux/sched.h>
  33 #include <sys/types.h>
  34 #include <sys/stat.h>
  35 #include <grp.h>
  36 #include <pwd.h>
  37 #include <sys/mount.h>
  38 #include <linux/fs.h>
  39
  40 #include "execute.h"
  41 #include "strv.h"
  42 #include "macro.h"
  43 #include "util.h"
  44 #include "log.h"
  45 #include "ioprio.h"
  46 #include "securebits.h"
  47 #include "cgroup.h"
  48 #include "namespace.h"
  49
  50 /* This assumes there is a 'tty' group */
  51 #define TTY_MODE 0620
  52
  53 static int shift_fds(int fds[], unsigned n_fds) {
  54         int start, restart_from;
  55
  56         if (n_fds <= 0)
  57                 return 0;
  58
  59         /* Modifies the fds array! (sorts it) */
  60
  61         assert(fds);
  62
  63         start = 0;
  64         for (;;) {
  65                 int i;
  66
  67                 restart_from = -1;
  68
  69                 for (i = start; i < (int) n_fds; i++) {
  70                         int nfd;
  71
  72                         /* Already at right index? */
  73                         if (fds[i] == i+3)
  74                                 continue;
  75
  76                         if ((nfd = fcntl(fds[i], F_DUPFD, i+3)) < 0)
  77                                 return -errno;
  78
  79                         close_nointr_nofail(fds[i]);
  80                         fds[i] = nfd;
  81
  82                         /* Hmm, the fd we wanted isn't free? Then
  83                          * let's remember that and try again from here*/
  84                         if (nfd != i+3 && restart_from < 0)
  85                                 restart_from = i;
  86                 }
  87
  88                 if (restart_from < 0)
  89                         break;
  90
  91                 start = restart_from;
  92         }
  93
  94         return 0;
  95 }
  96
  97 static int flags_fds(const int fds[], unsigned n_fds, bool nonblock) {
  98         unsigned i;
  99         int r;
 100
 101         if (n_fds <= 0)
 102                 return 0;
 103
 104         assert(fds);
 105
 106         /* Drops/Sets O_NONBLOCK and FD_CLOEXEC from the file flags */
 107
 108         for (i = 0; i < n_fds; i++) {
 109
 110                 if ((r = fd_nonblock(fds[i], nonblock)) < 0)
 111                         return r;
 112
 113                 /* We unconditionally drop FD_CLOEXEC from the fds,
 114                  * since after all we want to pass these fds to our
 115                  * children */
 116
 117                 if ((r = fd_cloexec(fds[i], false)) < 0)
 118                         return r;
 119         }
 120
 121         return 0;
 122 }
 123
 124 static const char *tty_path(const ExecContext *context) {
 125         assert(context);
 126
 127         if (context->tty_path)
 128                 return context->tty_path;
 129
 130         return "/dev/console";
 131 }
 132
 133 static int open_null_as(int flags, int nfd) {
 134         int fd, r;
 135
 136         assert(nfd >= 0);
 137
 138         if ((fd = open("/dev/null", flags|O_NOCTTY)) < 0)
 139                 return -errno;
 140
 141         if (fd != nfd) {
 142                 r = dup2(fd, nfd) < 0 ? -errno : nfd;
 143                 close_nointr_nofail(fd);
 144         } else
 145                 r = nfd;
 146
 147         return r;
 148 }
 149
 150 static int connect_logger_as(const ExecContext *context, ExecOutput output, const char *ident, int nfd) {
 151         int fd, r;
 152         union {
 153                 struct sockaddr sa;
 154                 struct sockaddr_un un;
 155         } sa;
 156
 157         assert(context);
 158         assert(output < _EXEC_OUTPUT_MAX);
 159         assert(ident);
 160         assert(nfd >= 0);
 161
 162         if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
 163                 return -errno;
 164
 165         zero(sa);
 166         sa.sa.sa_family = AF_UNIX;
 167         strncpy(sa.un.sun_path+1, LOGGER_SOCKET, sizeof(sa.un.sun_path)-1);
 168
 169         if (connect(fd, &sa.sa, sizeof(sa)) < 0) {
 170                 close_nointr_nofail(fd);
 171                 return -errno;
 172         }
 173
 174         if (shutdown(fd, SHUT_RD) < 0) {
 175                 close_nointr_nofail(fd);
 176                 return -errno;
 177         }
 178
 179         /* We speak a very simple protocol between log server
 180          * and client: one line for the log destination (kmsg
 181          * or syslog), followed by the priority field,
 182          * followed by the process name. Since we replaced
 183          * stdin/stderr we simple use stdio to write to
 184          * it. Note that we use stderr, to minimize buffer
 185          * flushing issues. */
 186
 187         dprintf(fd,
 188                 "%s\n"
 189                 "%i\n"
 190                 "%s\n"
 191                 "%i\n",
 192                 output == EXEC_OUTPUT_KMSG ? "kmsg" : "syslog",
 193                 context->syslog_priority,
 194                 context->syslog_identifier ? context->syslog_identifier : ident,
 195                 !context->syslog_no_prefix);
 196
 197         if (fd != nfd) {
 198                 r = dup2(fd, nfd) < 0 ? -errno : nfd;
 199                 close_nointr_nofail(fd);
 200         } else
 201                 r = nfd;
 202
 203         return r;
 204 }
 205 static int open_terminal_as(const char *path, mode_t mode, int nfd) {
 206         int fd, r;
 207
 208         assert(path);
 209         assert(nfd >= 0);
 210
 211         if ((fd = open_terminal(path, mode | O_NOCTTY)) < 0)
 212                 return fd;
 213
 214         if (fd != nfd) {
 215                 r = dup2(fd, nfd) < 0 ? -errno : nfd;
 216                 close_nointr_nofail(fd);
 217         } else
 218                 r = nfd;
 219
 220         return r;
 221 }
 222
 223 static bool is_terminal_input(ExecInput i) {
 224         return
 225                 i == EXEC_INPUT_TTY ||
 226                 i == EXEC_INPUT_TTY_FORCE ||
 227                 i == EXEC_INPUT_TTY_FAIL;
 228 }
 229
 230 static int fixup_input(ExecInput std_input, int socket_fd) {
 231
 232         if (std_input == EXEC_INPUT_SOCKET && socket_fd < 0)
 233                 return EXEC_INPUT_NULL;
 234
 235         return std_input;
 236 }
 237
 238 static int fixup_output(ExecOutput std_output, int socket_fd) {
 239
 240         if (std_output == EXEC_OUTPUT_SOCKET && socket_fd < 0)
 241                 return EXEC_OUTPUT_INHERIT;
 242
 243         return std_output;
 244 }
 245
 246 static int setup_input(const ExecContext *context, int socket_fd) {
 247         ExecInput i;
 248
 249         assert(context);
 250
 251         i = fixup_input(context->std_input, socket_fd);
 252
 253         switch (i) {
 254
 255         case EXEC_INPUT_NULL:
 256                 return open_null_as(O_RDONLY, STDIN_FILENO);
 257
 258         case EXEC_INPUT_TTY:
 259         case EXEC_INPUT_TTY_FORCE:
 260         case EXEC_INPUT_TTY_FAIL: {
 261                 int fd, r;
 262
 263                 if ((fd = acquire_terminal(
 264                                      tty_path(context),
 265                                      i == EXEC_INPUT_TTY_FAIL,
 266                                      i == EXEC_INPUT_TTY_FORCE,
 267                                      false)) < 0)
 268                         return fd;
 269
 270                 if (fd != STDIN_FILENO) {
 271                         r = dup2(fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
 272                         close_nointr_nofail(fd);
 273                 } else
 274                         r = STDIN_FILENO;
 275
 276                 return r;
 277         }
 278
 279         case EXEC_INPUT_SOCKET:
 280                 return dup2(socket_fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
 281
 282         default:
 283                 assert_not_reached("Unknown input type");
 284         }
 285 }
 286
 287 static int setup_output(const ExecContext *context, int socket_fd, const char *ident) {
 288         ExecOutput o;
 289         ExecInput i;
 290
 291         assert(context);
 292         assert(ident);
 293
 294         i = fixup_input(context->std_input, socket_fd);
 295         o = fixup_output(context->std_output, socket_fd);
 296
 297         /* This expects the input is already set up */
 298
 299         switch (o) {
 300
 301         case EXEC_OUTPUT_INHERIT:
 302
 303                 /* If the input is connected to a terminal, inherit that... */
 304                 if (i != EXEC_INPUT_NULL)
 305                         return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
 306
 307                 /* For PID 1 stdout is always connected to /dev/null,
 308                  * hence reopen the console if out parent is PID1. */
 309                 if (getppid() == 1)
 310                         return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
 311
 312                 return STDOUT_FILENO;
 313
 314         case EXEC_OUTPUT_NULL:
 315                 return open_null_as(O_WRONLY, STDOUT_FILENO);
 316
 317         case EXEC_OUTPUT_TTY:
 318                 if (is_terminal_input(i))
 319                         return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
 320
 321                 /* We don't reset the terminal if this is just about output */
 322                 return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
 323
 324         case EXEC_OUTPUT_SYSLOG:
 325         case EXEC_OUTPUT_KMSG:
 326                 return connect_logger_as(context, o, ident, STDOUT_FILENO);
 327
 328         case EXEC_OUTPUT_SOCKET:
 329                 assert(socket_fd >= 0);
 330                 return dup2(socket_fd, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
 331
 332         default:
 333                 assert_not_reached("Unknown output type");
 334         }
 335 }
 336
 337 static int setup_error(const ExecContext *context, int socket_fd, const char *ident) {
 338         ExecOutput o, e;
 339         ExecInput i;
 340
 341         assert(context);
 342         assert(ident);
 343
 344         i = fixup_input(context->std_input, socket_fd);
 345         o = fixup_output(context->std_output, socket_fd);
 346         e = fixup_output(context->std_error, socket_fd);
 347
 348         /* This expects the input and output are already set up */
 349
 350         /* Don't change the stderr file descriptor if we inherit all
 351          * the way and are not on a tty */
 352         if (e == EXEC_OUTPUT_INHERIT &&
 353             o == EXEC_OUTPUT_INHERIT &&
 354             i != EXEC_INPUT_NULL &&
 355             getppid () != 1)
 356                 return STDERR_FILENO;
 357
 358         /* Duplicate form stdout if possible */
 359         if (e == o || e == EXEC_OUTPUT_INHERIT)
 360                 return dup2(STDOUT_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
 361
 362         switch (e) {
 363
 364         case EXEC_OUTPUT_NULL:
 365                 return open_null_as(O_WRONLY, STDERR_FILENO);
 366
 367         case EXEC_OUTPUT_TTY:
 368                 if (is_terminal_input(i))
 369                         return dup2(STDIN_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
 370
 371                 /* We don't reset the terminal if this is just about output */
 372                 return open_terminal_as(tty_path(context), O_WRONLY, STDERR_FILENO);
 373
 374         case EXEC_OUTPUT_SYSLOG:
 375         case EXEC_OUTPUT_KMSG:
 376                 return connect_logger_as(context, e, ident, STDERR_FILENO);
 377
 378         case EXEC_OUTPUT_SOCKET:
 379                 assert(socket_fd >= 0);
 380                 return dup2(socket_fd, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
 381
 382         default:
 383                 assert_not_reached("Unknown error type");
 384         }
 385 }
 386
 387 static int chown_terminal(int fd, uid_t uid) {
 388         struct stat st;
 389
 390         assert(fd >= 0);
 391
 392         /* This might fail. What matters are the results. */
 393         (void) fchown(fd, uid, -1);
 394         (void) fchmod(fd, TTY_MODE);
 395
 396         if (fstat(fd, &st) < 0)
 397                 return -errno;
 398
 399         if (st.st_uid != uid || (st.st_mode & 0777) != TTY_MODE)
 400                 return -EPERM;
 401
 402         return 0;
 403 }
 404
 405 static int setup_confirm_stdio(const ExecContext *context,
 406                                int *_saved_stdin,
 407                                int *_saved_stdout) {
 408         int fd = -1, saved_stdin, saved_stdout = -1, r;
 409
 410         assert(context);
 411         assert(_saved_stdin);
 412         assert(_saved_stdout);
 413
 414         /* This returns positive EXIT_xxx return values instead of
 415          * negative errno style values! */
 416
 417         if ((saved_stdin = fcntl(STDIN_FILENO, F_DUPFD, 3)) < 0)
 418                 return EXIT_STDIN;
 419
 420         if ((saved_stdout = fcntl(STDOUT_FILENO, F_DUPFD, 3)) < 0) {
 421                 r = EXIT_STDOUT;
 422                 goto fail;
 423         }
 424
 425         if ((fd = acquire_terminal(
 426                              tty_path(context),
 427                              context->std_input == EXEC_INPUT_TTY_FAIL,
 428                              context->std_input == EXEC_INPUT_TTY_FORCE,
 429                              false)) < 0) {
 430                 r = EXIT_STDIN;
 431                 goto fail;
 432         }
 433
 434         if (chown_terminal(fd, getuid()) < 0) {
 435                 r = EXIT_STDIN;
 436                 goto fail;
 437         }
 438
 439         if (dup2(fd, STDIN_FILENO) < 0) {
 440                 r = EXIT_STDIN;
 441                 goto fail;
 442         }
 443
 444         if (dup2(fd, STDOUT_FILENO) < 0) {
 445                 r = EXIT_STDOUT;
 446                 goto fail;
 447         }
 448
 449         if (fd >= 2)
 450                 close_nointr_nofail(fd);
 451
 452         *_saved_stdin = saved_stdin;
 453         *_saved_stdout = saved_stdout;
 454
 455         return 0;
 456
 457 fail:
 458         if (saved_stdout >= 0)
 459                 close_nointr_nofail(saved_stdout);
 460
 461         if (saved_stdin >= 0)
 462                 close_nointr_nofail(saved_stdin);
 463
 464         if (fd >= 0)
 465                 close_nointr_nofail(fd);
 466
 467         return r;
 468 }
 469
 470 static int restore_confirm_stdio(const ExecContext *context,
 471                                  int *saved_stdin,
 472                                  int *saved_stdout,
 473                                  bool *keep_stdin,
 474                                  bool *keep_stdout) {
 475
 476         assert(context);
 477         assert(saved_stdin);
 478         assert(*saved_stdin >= 0);
 479         assert(saved_stdout);
 480         assert(*saved_stdout >= 0);
 481
 482         /* This returns positive EXIT_xxx return values instead of
 483          * negative errno style values! */
 484
 485         if (is_terminal_input(context->std_input)) {
 486
 487                 /* The service wants terminal input. */
 488
 489                 *keep_stdin = true;
 490                 *keep_stdout =
 491                         context->std_output == EXEC_OUTPUT_INHERIT ||
 492                         context->std_output == EXEC_OUTPUT_TTY;
 493
 494         } else {
 495                 /* If the service doesn't want a controlling terminal,
 496                  * then we need to get rid entirely of what we have
 497                  * already. */
 498
 499                 if (release_terminal() < 0)
 500                         return EXIT_STDIN;
 501
 502                 if (dup2(*saved_stdin, STDIN_FILENO) < 0)
 503                         return EXIT_STDIN;
 504
 505                 if (dup2(*saved_stdout, STDOUT_FILENO) < 0)
 506                         return EXIT_STDOUT;
 507
 508                 *keep_stdout = *keep_stdin = false;
 509         }
 510
 511         return 0;
 512 }
 513
 514 static int get_group_creds(const char *groupname, gid_t *gid) {
 515         struct group *g;
 516         unsigned long lu;
 517
 518         assert(groupname);
 519         assert(gid);
 520
 521         /* We enforce some special rules for gid=0: in order to avoid
 522          * NSS lookups for root we hardcode its data. */
 523
 524         if (streq(groupname, "root") || streq(groupname, "0")) {
 525                 *gid = 0;
 526                 return 0;
 527         }
 528
 529         if (safe_atolu(groupname, &lu) >= 0) {
 530                 errno = 0;
 531                 g = getgrgid((gid_t) lu);
 532         } else {
 533                 errno = 0;
 534                 g = getgrnam(groupname);
 535         }
 536
 537         if (!g)
 538                 return errno != 0 ? -errno : -ESRCH;
 539
 540         *gid = g->gr_gid;
 541         return 0;
 542 }
 543
 544 static int get_user_creds(const char **username, uid_t *uid, gid_t *gid, const char **home) {
 545         struct passwd *p;
 546         unsigned long lu;
 547
 548         assert(username);
 549         assert(*username);
 550         assert(uid);
 551         assert(gid);
 552         assert(home);
 553
 554         /* We enforce some special rules for uid=0: in order to avoid
 555          * NSS lookups for root we hardcode its data. */
 556
 557         if (streq(*username, "root") || streq(*username, "0")) {
 558                 *username = "root";
 559                 *uid = 0;
 560                 *gid = 0;
 561                 *home = "/root";
 562                 return 0;
 563         }
 564
 565         if (safe_atolu(*username, &lu) >= 0) {
 566                 errno = 0;
 567                 p = getpwuid((uid_t) lu);
 568
 569                 /* If there are multiple users with the same id, make
 570                  * sure to leave $USER to the configured value instead
 571                  * of the first occurence in the database. However if
 572                  * the uid was configured by a numeric uid, then let's
 573                  * pick the real username from /etc/passwd. */
 574                 if (*username && p)
 575                         *username = p->pw_name;
 576         } else {
 577                 errno = 0;
 578                 p = getpwnam(*username);
 579         }
 580
 581         if (!p)
 582                 return errno != 0 ? -errno : -ESRCH;
 583
 584         *uid = p->pw_uid;
 585         *gid = p->pw_gid;
 586         *home = p->pw_dir;
 587         return 0;
 588 }
 589
 590 static int enforce_groups(const ExecContext *context, const char *username, gid_t gid) {
 591         bool keep_groups = false;
 592         int r;
 593
 594         assert(context);
 595
 596         /* Lookup and ser GID and supplementary group list. Here too
 597          * we avoid NSS lookups for gid=0. */
 598
 599         if (context->group || username) {
 600
 601                 if (context->group)
 602                         if ((r = get_group_creds(context->group, &gid)) < 0)
 603                                 return r;
 604
 605                 /* First step, initialize groups from /etc/groups */
 606                 if (username && gid != 0) {
 607                         if (initgroups(username, gid) < 0)
 608                                 return -errno;
 609
 610                         keep_groups = true;
 611                 }
 612
 613                 /* Second step, set our gids */
 614                 if (setresgid(gid, gid, gid) < 0)
 615                         return -errno;
 616         }
 617
 618         if (context->supplementary_groups) {
 619                 int ngroups_max, k;
 620                 gid_t *gids;
 621                 char **i;
 622
 623                 /* Final step, initialize any manually set supplementary groups */
 624                 ngroups_max = (int) sysconf(_SC_NGROUPS_MAX);
 625
 626                 if (!(gids = new(gid_t, ngroups_max)))
 627                         return -ENOMEM;
 628
 629                 if (keep_groups) {
 630                         if ((k = getgroups(ngroups_max, gids)) < 0) {
 631                                 free(gids);
 632                                 return -errno;
 633                         }
 634                 } else
 635                         k = 0;
 636
 637                 STRV_FOREACH(i, context->supplementary_groups) {
 638
 639                         if (k >= ngroups_max) {
 640                                 free(gids);
 641                                 return -E2BIG;
 642                         }
 643
 644                         if ((r = get_group_creds(*i, gids+k)) < 0) {
 645                                 free(gids);
 646                                 return r;
 647                         }
 648
 649                         k++;
 650                 }
 651
 652                 if (setgroups(k, gids) < 0) {
 653                         free(gids);
 654                         return -errno;
 655                 }
 656
 657                 free(gids);
 658         }
 659
 660         return 0;
 661 }
 662
 663 static int enforce_user(const ExecContext *context, uid_t uid) {
 664         int r;
 665         assert(context);
 666
 667         /* Sets (but doesn't lookup) the uid and make sure we keep the
 668          * capabilities while doing so. */
 669
 670         if (context->capabilities) {
 671                 cap_t d;
 672                 static const cap_value_t bits[] = {
 673                         CAP_SETUID,   /* Necessary so that we can run setresuid() below */
 674                         CAP_SETPCAP   /* Necessary so that we can set PR_SET_SECUREBITS later on */
 675                 };
 676
 677                 /* First step: If we need to keep capabilities but
 678                  * drop privileges we need to make sure we keep our
 679                  * caps, whiel we drop priviliges. */
 680                 if (uid != 0) {
 681                         int sb = context->secure_bits|SECURE_KEEP_CAPS;
 682
 683                         if (prctl(PR_GET_SECUREBITS) != sb)
 684                                 if (prctl(PR_SET_SECUREBITS, sb) < 0)
 685                                         return -errno;
 686                 }
 687
 688                 /* Second step: set the capabilites. This will reduce
 689                  * the capabilities to the minimum we need. */
 690
 691                 if (!(d = cap_dup(context->capabilities)))
 692                         return -errno;
 693
 694                 if (cap_set_flag(d, CAP_EFFECTIVE, ELEMENTSOF(bits), bits, CAP_SET) < 0 ||
 695                     cap_set_flag(d, CAP_PERMITTED, ELEMENTSOF(bits), bits, CAP_SET) < 0) {
 696                         r = -errno;
 697                         cap_free(d);
 698                         return r;
 699                 }
 700
 701                 if (cap_set_proc(d) < 0) {
 702                         r = -errno;
 703                         cap_free(d);
 704                         return r;
 705                 }
 706
 707                 cap_free(d);
 708         }
 709
 710         /* Third step: actually set the uids */
 711         if (setresuid(uid, uid, uid) < 0)
 712                 return -errno;
 713
 714         /* At this point we should have all necessary capabilities but
 715            are otherwise a normal user. However, the caps might got
 716            corrupted due to the setresuid() so we need clean them up
 717            later. This is done outside of this call. */
 718
 719         return 0;
 720 }
 721
 722 int exec_spawn(ExecCommand *command,
 723                char **argv,
 724                const ExecContext *context,
 725                int fds[], unsigned n_fds,
 726                char **environment,
 727                bool apply_permissions,
 728                bool apply_chroot,
 729                bool confirm_spawn,
 730                CGroupBonding *cgroup_bondings,
 731                pid_t *ret) {
 732
 733         pid_t pid;
 734         int r;
 735         char *line;
 736         int socket_fd;
 737
 738         assert(command);
 739         assert(context);
 740         assert(ret);
 741         assert(fds || n_fds <= 0);
 742
 743         if (context->std_input == EXEC_INPUT_SOCKET ||
 744             context->std_output == EXEC_OUTPUT_SOCKET ||
 745             context->std_error == EXEC_OUTPUT_SOCKET) {
 746
 747                 if (n_fds != 1)
 748                         return -EINVAL;
 749
 750                 socket_fd = fds[0];
 751
 752                 fds = NULL;
 753                 n_fds = 0;
 754         } else
 755                 socket_fd = -1;
 756
 757         if (!argv)
 758                 argv = command->argv;
 759
 760         if (!(line = exec_command_line(argv)))
 761                 return -ENOMEM;
 762
 763         log_debug("About to execute: %s", line);
 764         free(line);
 765
 766         if (cgroup_bondings)
 767                 if ((r = cgroup_bonding_realize_list(cgroup_bondings)))
 768                         return r;
 769
 770         if ((pid = fork()) < 0)
 771                 return -errno;
 772
 773         if (pid == 0) {
 774                 int i;
 775                 sigset_t ss;
 776                 const char *username = NULL, *home = NULL;
 777                 uid_t uid = (uid_t) -1;
 778                 gid_t gid = (gid_t) -1;
 779                 char **our_env = NULL, **final_env = NULL;
 780                 unsigned n_env = 0;
 781                 int saved_stdout = -1, saved_stdin = -1;
 782                 bool keep_stdout = false, keep_stdin = false;
 783
 784                 /* child */
 785
 786                 /* We reset exactly these two signals, since they are
 787                  * the only ones we set to SIG_IGN in the main
 788                  * daemon. All others */
 789                 default_signals(SIGNALS_CRASH_HANLDER,
 790                                 SIGNALS_IGNORE, -1);
 791
 792                 if (sigemptyset(&ss) < 0 ||
 793                     sigprocmask(SIG_SETMASK, &ss, NULL) < 0) {
 794                         r = EXIT_SIGNAL_MASK;
 795                         goto fail;
 796                 }
 797
 798                 if (!context->no_setsid)
 799                         if (setsid() < 0) {
 800                                 r = EXIT_SETSID;
 801                                 goto fail;
 802                         }
 803
 804                 if (confirm_spawn) {
 805                         char response;
 806
 807                         /* Set up terminal for the question */
 808                         if ((r = setup_confirm_stdio(context,
 809                                                      &saved_stdin, &saved_stdout)))
 810                                 goto fail;
 811
 812                         /* Now ask the question. */
 813                         if (!(line = exec_command_line(argv))) {
 814                                 r = EXIT_MEMORY;
 815                                 goto fail;
 816                         }
 817
 818                         r = ask(&response, "yns", "Execute %s? [Yes, No, Skip] ", line);
 819                         free(line);
 820
 821                         if (r < 0 || response == 'n') {
 822                                 r = EXIT_CONFIRM;
 823                                 goto fail;
 824                         } else if (response == 's') {
 825                                 r = 0;
 826                                 goto fail;
 827                         }
 828
 829                         /* Release terminal for the question */
 830                         if ((r = restore_confirm_stdio(context,
 831                                                        &saved_stdin, &saved_stdout,
 832                                                        &keep_stdin, &keep_stdout)))
 833                                 goto fail;
 834                 }
 835
 836                 if (!keep_stdin)
 837                         if (setup_input(context, socket_fd) < 0) {
 838                                 r = EXIT_STDIN;
 839                                 goto fail;
 840                         }
 841
 842                 if (!keep_stdout)
 843                         if (setup_output(context, socket_fd, file_name_from_path(command->path)) < 0) {
 844                                 r = EXIT_STDOUT;
 845                                 goto fail;
 846                         }
 847
 848                 if (setup_error(context, socket_fd, file_name_from_path(command->path)) < 0) {
 849                         r = EXIT_STDERR;
 850                         goto fail;
 851                 }
 852
 853                 if (cgroup_bondings)
 854                         if ((r = cgroup_bonding_install_list(cgroup_bondings, 0)) < 0) {
 855                                 r = EXIT_CGROUP;
 856                                 goto fail;
 857                         }
 858
 859                 if (context->oom_adjust_set) {
 860                         char t[16];
 861
 862                         snprintf(t, sizeof(t), "%i", context->oom_adjust);
 863                         char_array_0(t);
 864
 865                         if (write_one_line_file("/proc/self/oom_adj", t) < 0) {
 866                                 r = EXIT_OOM_ADJUST;
 867                                 goto fail;
 868                         }
 869                 }
 870
 871                 if (context->nice_set)
 872                         if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
 873                                 r = EXIT_NICE;
 874                                 goto fail;
 875                         }
 876
 877                 if (context->cpu_sched_set) {
 878                         struct sched_param param;
 879
 880                         zero(param);
 881                         param.sched_priority = context->cpu_sched_priority;
 882
 883                         if (sched_setscheduler(0, context->cpu_sched_policy |
 884                                                (context->cpu_sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0), &param) < 0) {
 885                                 r = EXIT_SETSCHEDULER;
 886                                 goto fail;
 887                         }
 888                 }
 889
 890                 if (context->cpu_affinity_set)
 891                         if (sched_setaffinity(0, sizeof(context->cpu_affinity), &context->cpu_affinity) < 0) {
 892                                 r = EXIT_CPUAFFINITY;
 893                                 goto fail;
 894                         }
 895
 896                 if (context->ioprio_set)
 897                         if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
 898                                 r = EXIT_IOPRIO;
 899                                 goto fail;
 900                         }
 901
 902                 if (context->timer_slack_ns_set)
 903                         if (prctl(PR_SET_TIMERSLACK, context->timer_slack_ns_set) < 0) {
 904                                 r = EXIT_TIMERSLACK;
 905                                 goto fail;
 906                         }
 907
 908                 if (strv_length(context->read_write_dirs) > 0 ||
 909                     strv_length(context->read_only_dirs) > 0 ||
 910                     strv_length(context->inaccessible_dirs) > 0 ||
 911                     context->mount_flags != MS_SHARED ||
 912                     context->private_tmp)
 913                         if ((r = setup_namespace(
 914                                              context->read_write_dirs,
 915                                              context->read_only_dirs,
 916                                              context->inaccessible_dirs,
 917                                              context->private_tmp,
 918                                              context->mount_flags)) < 0)
 919                                 goto fail;
 920
 921                 if (context->user) {
 922                         username = context->user;
 923                         if (get_user_creds(&username, &uid, &gid, &home) < 0) {
 924                                 r = EXIT_USER;
 925                                 goto fail;
 926                         }
 927
 928                         if (is_terminal_input(context->std_input))
 929                                 if (chown_terminal(STDIN_FILENO, uid) < 0) {
 930                                         r = EXIT_STDIN;
 931                                         goto fail;
 932                                 }
 933                 }
 934
 935                 if (apply_permissions)
 936                         if (enforce_groups(context, username, uid) < 0) {
 937                                 r = EXIT_GROUP;
 938                                 goto fail;
 939                         }
 940
 941                 umask(context->umask);
 942
 943                 if (apply_chroot) {
 944                         if (context->root_directory)
 945                                 if (chroot(context->root_directory) < 0) {
 946                                         r = EXIT_CHROOT;
 947                                         goto fail;
 948                                 }
 949
 950                         if (chdir(context->working_directory ? context->working_directory : "/") < 0) {
 951                                 r = EXIT_CHDIR;
 952                                 goto fail;
 953                         }
 954                 } else {
 955
 956                         char *d;
 957
 958                         if (asprintf(&d, "%s/%s",
 959                                      context->root_directory ? context->root_directory : "",
 960                                      context->working_directory ? context->working_directory : "") < 0) {
 961                                 r = EXIT_MEMORY;
 962                                 goto fail;
 963                         }
 964
 965                         if (chdir(d) < 0) {
 966                                 free(d);
 967                                 r = EXIT_CHDIR;
 968                                 goto fail;
 969                         }
 970
 971                         free(d);
 972                 }
 973
 974                 if (close_all_fds(fds, n_fds) < 0 ||
 975                     shift_fds(fds, n_fds) < 0 ||
 976                     flags_fds(fds, n_fds, context->non_blocking) < 0) {
 977                         r = EXIT_FDS;
 978                         goto fail;
 979                 }
 980
 981                 if (apply_permissions) {
 982
 983                         for (i = 0; i < RLIMIT_NLIMITS; i++) {
 984                                 if (!context->rlimit[i])
 985                                         continue;
 986
 987                                 if (setrlimit(i, context->rlimit[i]) < 0) {
 988                                         r = EXIT_LIMITS;
 989                                         goto fail;
 990                                 }
 991                         }
 992
 993                         if (context->user)
 994                                 if (enforce_user(context, uid) < 0) {
 995                                         r = EXIT_USER;
 996                                         goto fail;
 997                                 }
 998
 999                         /* PR_GET_SECUREBITS is not priviliged, while
1000                          * PR_SET_SECUREBITS is. So to suppress
1001                          * potential EPERMs we'll try not to call
1002                          * PR_SET_SECUREBITS unless necessary. */
1003                         if (prctl(PR_GET_SECUREBITS) != context->secure_bits)
1004                                 if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {
1005                                         r = EXIT_SECUREBITS;
1006                                         goto fail;
1007                                 }
1008
1009                         if (context->capabilities)
1010                                 if (cap_set_proc(context->capabilities) < 0) {
1011                                         r = EXIT_CAPABILITIES;
1012                                         goto fail;
1013                                 }
1014                 }
1015
1016                 if (!(our_env = new0(char*, 6))) {
1017                         r = EXIT_MEMORY;
1018                         goto fail;
1019                 }
1020
1021                 if (n_fds > 0)
1022                         if (asprintf(our_env + n_env++, "LISTEN_PID=%llu", (unsigned long long) getpid()) < 0 ||
1023                             asprintf(our_env + n_env++, "LISTEN_FDS=%u", n_fds) < 0) {
1024                                 r = EXIT_MEMORY;
1025                                 goto fail;
1026                         }
1027
1028                 if (home)
1029                         if (asprintf(our_env + n_env++, "HOME=%s", home) < 0) {
1030                                 r = EXIT_MEMORY;
1031                                 goto fail;
1032                         }
1033
1034                 if (username)
1035                         if (asprintf(our_env + n_env++, "LOGNAME=%s", username) < 0 ||
1036                             asprintf(our_env + n_env++, "USER=%s", username) < 0) {
1037                                 r = EXIT_MEMORY;
1038                                 goto fail;
1039                         }
1040
1041                 assert(n_env <= 6);
1042
1043                 if (!(final_env = strv_env_merge(environment, our_env, context->environment, NULL))) {
1044                         r = EXIT_MEMORY;
1045                         goto fail;
1046                 }
1047
1048                 execve(command->path, argv, final_env);
1049                 r = EXIT_EXEC;
1050
1051         fail:
1052                 strv_free(our_env);
1053                 strv_free(final_env);
1054
1055                 if (saved_stdin >= 0)
1056                         close_nointr_nofail(saved_stdin);
1057
1058                 if (saved_stdout >= 0)
1059                         close_nointr_nofail(saved_stdout);
1060
1061                 _exit(r);
1062         }
1063
1064         /* We add the new process to the cgroup both in the child (so
1065          * that we can be sure that no user code is ever executed
1066          * outside of the cgroup) and in the parent (so that we can be
1067          * sure that when we kill the cgroup the process will be
1068          * killed too). */
1069         if (cgroup_bondings)
1070                 cgroup_bonding_install_list(cgroup_bondings, pid);
1071
1072         log_debug("Forked %s as %llu", command->path, (unsigned long long) pid);
1073
1074         command->exec_status.pid = pid;
1075         command->exec_status.start_timestamp = now(CLOCK_REALTIME);
1076
1077         *ret = pid;
1078         return 0;
1079 }
1080
1081 void exec_context_init(ExecContext *c) {
1082         assert(c);
1083
1084         c->umask = 0002;
1085         c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
1086         c->cpu_sched_policy = SCHED_OTHER;
1087         c->syslog_priority = LOG_DAEMON|LOG_INFO;
1088         c->mount_flags = MS_SHARED;
1089 }
1090
1091 void exec_context_done(ExecContext *c) {
1092         unsigned l;
1093
1094         assert(c);
1095
1096         strv_free(c->environment);
1097         c->environment = NULL;
1098
1099         for (l = 0; l < ELEMENTSOF(c->rlimit); l++) {
1100                 free(c->rlimit[l]);
1101                 c->rlimit[l] = NULL;
1102         }
1103
1104         free(c->working_directory);
1105         c->working_directory = NULL;
1106         free(c->root_directory);
1107         c->root_directory = NULL;
1108
1109         free(c->tty_path);
1110         c->tty_path = NULL;
1111
1112         free(c->syslog_identifier);
1113         c->syslog_identifier = NULL;
1114
1115         free(c->user);
1116         c->user = NULL;
1117
1118         free(c->group);
1119         c->group = NULL;
1120
1121         strv_free(c->supplementary_groups);
1122         c->supplementary_groups = NULL;
1123
1124         if (c->capabilities) {
1125                 cap_free(c->capabilities);
1126                 c->capabilities = NULL;
1127         }
1128
1129         strv_free(c->read_only_dirs);
1130         c->read_only_dirs = NULL;
1131
1132         strv_free(c->read_write_dirs);
1133         c->read_write_dirs = NULL;
1134
1135         strv_free(c->inaccessible_dirs);
1136         c->inaccessible_dirs = NULL;
1137 }
1138
1139 void exec_command_done(ExecCommand *c) {
1140         assert(c);
1141
1142         free(c->path);
1143         c->path = NULL;
1144
1145         strv_free(c->argv);
1146         c->argv = NULL;
1147 }
1148
1149 void exec_command_done_array(ExecCommand *c, unsigned n) {
1150         unsigned i;
1151
1152         for (i = 0; i < n; i++)
1153                 exec_command_done(c+i);
1154 }
1155
1156 void exec_command_free_list(ExecCommand *c) {
1157         ExecCommand *i;
1158
1159         while ((i = c)) {
1160                 LIST_REMOVE(ExecCommand, command, c, i);
1161                 exec_command_done(i);
1162                 free(i);
1163         }
1164 }
1165
1166 void exec_command_free_array(ExecCommand **c, unsigned n) {
1167         unsigned i;
1168
1169         for (i = 0; i < n; i++) {
1170                 exec_command_free_list(c[i]);
1171                 c[i] = NULL;
1172         }
1173 }
1174
1175 static void strv_fprintf(FILE *f, char **l) {
1176         char **g;
1177
1178         assert(f);
1179
1180         STRV_FOREACH(g, l)
1181                 fprintf(f, " %s", *g);
1182 }
1183
1184 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
1185         char ** e;
1186         unsigned i;
1187
1188         assert(c);
1189         assert(f);
1190
1191         if (!prefix)
1192                 prefix = "";
1193
1194         fprintf(f,
1195                 "%sUMask: %04o\n"
1196                 "%sWorkingDirectory: %s\n"
1197                 "%sRootDirectory: %s\n"
1198                 "%sNonBlocking: %s\n"
1199                 "%sPrivateTmp: %s\n",
1200                 prefix, c->umask,
1201                 prefix, c->working_directory ? c->working_directory : "/",
1202                 prefix, c->root_directory ? c->root_directory : "/",
1203                 prefix, yes_no(c->non_blocking),
1204                 prefix, yes_no(c->private_tmp));
1205
1206         if (c->environment)
1207                 for (e = c->environment; *e; e++)
1208                         fprintf(f, "%sEnvironment: %s\n", prefix, *e);
1209
1210         if (c->nice_set)
1211                 fprintf(f,
1212                         "%sNice: %i\n",
1213                         prefix, c->nice);
1214
1215         if (c->oom_adjust_set)
1216                 fprintf(f,
1217                         "%sOOMAdjust: %i\n",
1218                         prefix, c->oom_adjust);
1219
1220         for (i = 0; i < RLIM_NLIMITS; i++)
1221                 if (c->rlimit[i])
1222                         fprintf(f, "%s%s: %llu\n", prefix, rlimit_to_string(i), (unsigned long long) c->rlimit[i]->rlim_max);
1223
1224         if (c->ioprio_set)
1225                 fprintf(f,
1226                         "%sIOSchedulingClass: %s\n"
1227                         "%sIOPriority: %i\n",
1228                         prefix, ioprio_class_to_string(IOPRIO_PRIO_CLASS(c->ioprio)),
1229                         prefix, (int) IOPRIO_PRIO_DATA(c->ioprio));
1230
1231         if (c->cpu_sched_set)
1232                 fprintf(f,
1233                         "%sCPUSchedulingPolicy: %s\n"
1234                         "%sCPUSchedulingPriority: %i\n"
1235                         "%sCPUSchedulingResetOnFork: %s\n",
1236                         prefix, sched_policy_to_string(c->cpu_sched_policy),
1237                         prefix, c->cpu_sched_priority,
1238                         prefix, yes_no(c->cpu_sched_reset_on_fork));
1239
1240         if (c->cpu_affinity_set) {
1241                 fprintf(f, "%sCPUAffinity:", prefix);
1242                 for (i = 0; i < CPU_SETSIZE; i++)
1243                         if (CPU_ISSET(i, &c->cpu_affinity))
1244                                 fprintf(f, " %i", i);
1245                 fputs("\n", f);
1246         }
1247
1248         if (c->timer_slack_ns_set)
1249                 fprintf(f, "%sTimerSlackNS: %lu\n", prefix, c->timer_slack_ns);
1250
1251         fprintf(f,
1252                 "%sStandardInput: %s\n"
1253                 "%sStandardOutput: %s\n"
1254                 "%sStandardError: %s\n",
1255                 prefix, exec_input_to_string(c->std_input),
1256                 prefix, exec_output_to_string(c->std_output),
1257                 prefix, exec_output_to_string(c->std_error));
1258
1259         if (c->tty_path)
1260                 fprintf(f,
1261                         "%sTTYPath: %s\n",
1262                         prefix, c->tty_path);
1263
1264         if (c->std_output == EXEC_OUTPUT_SYSLOG || c->std_output == EXEC_OUTPUT_KMSG ||
1265             c->std_error == EXEC_OUTPUT_SYSLOG || c->std_error == EXEC_OUTPUT_KMSG)
1266                 fprintf(f,
1267                         "%sSyslogFacility: %s\n"
1268                         "%sSyslogLevel: %s\n",
1269                         prefix, log_facility_to_string(LOG_FAC(c->syslog_priority)),
1270                         prefix, log_level_to_string(LOG_PRI(c->syslog_priority)));
1271
1272         if (c->capabilities) {
1273                 char *t;
1274                 if ((t = cap_to_text(c->capabilities, NULL))) {
1275                         fprintf(f, "%sCapabilities: %s\n",
1276                                 prefix, t);
1277                         cap_free(t);
1278                 }
1279         }
1280
1281         if (c->secure_bits)
1282                 fprintf(f, "%sSecure Bits:%s%s%s%s%s%s\n",
1283                         prefix,
1284                         (c->secure_bits & SECURE_KEEP_CAPS) ? " keep-caps" : "",
1285                         (c->secure_bits & SECURE_KEEP_CAPS_LOCKED) ? " keep-caps-locked" : "",
1286                         (c->secure_bits & SECURE_NO_SETUID_FIXUP) ? " no-setuid-fixup" : "",
1287                         (c->secure_bits & SECURE_NO_SETUID_FIXUP_LOCKED) ? " no-setuid-fixup-locked" : "",
1288                         (c->secure_bits & SECURE_NOROOT) ? " noroot" : "",
1289                         (c->secure_bits & SECURE_NOROOT_LOCKED) ? "noroot-locked" : "");
1290
1291         if (c->capability_bounding_set_drop) {
1292                 fprintf(f, "%sCapabilityBoundingSetDrop:", prefix);
1293
1294                 for (i = 0; i <= CAP_LAST_CAP; i++)
1295                         if (c->capability_bounding_set_drop & (1 << i)) {
1296                                 char *t;
1297
1298                                 if ((t = cap_to_name(i))) {
1299                                         fprintf(f, " %s", t);
1300                                         free(t);
1301                                 }
1302                         }
1303
1304                 fputs("\n", f);
1305         }
1306
1307         if (c->user)
1308                 fprintf(f, "%sUser: %s", prefix, c->user);
1309         if (c->group)
1310                 fprintf(f, "%sGroup: %s", prefix, c->group);
1311
1312         if (strv_length(c->supplementary_groups) > 0) {
1313                 fprintf(f, "%sSupplementaryGroups:", prefix);
1314                 strv_fprintf(f, c->supplementary_groups);
1315                 fputs("\n", f);
1316         }
1317
1318         if (strv_length(c->read_write_dirs) > 0) {
1319                 fprintf(f, "%sReadWriteDirs:", prefix);
1320                 strv_fprintf(f, c->read_write_dirs);
1321                 fputs("\n", f);
1322         }
1323
1324         if (strv_length(c->read_only_dirs) > 0) {
1325                 fprintf(f, "%sReadOnlyDirs:", prefix);
1326                 strv_fprintf(f, c->read_only_dirs);
1327                 fputs("\n", f);
1328         }
1329
1330         if (strv_length(c->inaccessible_dirs) > 0) {
1331                 fprintf(f, "%sInaccessibleDirs:", prefix);
1332                 strv_fprintf(f, c->inaccessible_dirs);
1333                 fputs("\n", f);
1334         }
1335 }
1336
1337 void exec_status_fill(ExecStatus *s, pid_t pid, int code, int status) {
1338         assert(s);
1339
1340         s->pid = pid;
1341         s->exit_timestamp = now(CLOCK_REALTIME);
1342
1343         s->code = code;
1344         s->status = status;
1345 }
1346
1347 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix) {
1348         char buf[FORMAT_TIMESTAMP_MAX];
1349
1350         assert(s);
1351         assert(f);
1352
1353         if (!prefix)
1354                 prefix = "";
1355
1356         if (s->pid <= 0)
1357                 return;
1358
1359         fprintf(f,
1360                 "%sPID: %llu\n",
1361                 prefix, (unsigned long long) s->pid);
1362
1363         if (s->start_timestamp > 0)
1364                 fprintf(f,
1365                         "%sStart Timestamp: %s\n",
1366                         prefix, format_timestamp(buf, sizeof(buf), s->start_timestamp));
1367
1368         if (s->exit_timestamp > 0)
1369                 fprintf(f,
1370                         "%sExit Timestamp: %s\n"
1371                         "%sExit Code: %s\n"
1372                         "%sExit Status: %i\n",
1373                         prefix, format_timestamp(buf, sizeof(buf), s->exit_timestamp),
1374                         prefix, sigchld_code_to_string(s->code),
1375                         prefix, s->status);
1376 }
1377
1378 char *exec_command_line(char **argv) {
1379         size_t k;
1380         char *n, *p, **a;
1381         bool first = true;
1382
1383         assert(argv);
1384
1385         k = 1;
1386         STRV_FOREACH(a, argv)
1387                 k += strlen(*a)+3;
1388
1389         if (!(n = new(char, k)))
1390                 return NULL;
1391
1392         p = n;
1393         STRV_FOREACH(a, argv) {
1394
1395                 if (!first)
1396                         *(p++) = ' ';
1397                 else
1398                         first = false;
1399
1400                 if (strpbrk(*a, WHITESPACE)) {
1401                         *(p++) = '\'';
1402                         p = stpcpy(p, *a);
1403                         *(p++) = '\'';
1404                 } else
1405                         p = stpcpy(p, *a);
1406
1407         }
1408
1409         *p = 0;
1410
1411         /* FIXME: this doesn't really handle arguments that have
1412          * spaces and ticks in them */
1413
1414         return n;
1415 }
1416
1417 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
1418         char *p2;
1419         const char *prefix2;
1420
1421         char *cmd;
1422
1423         assert(c);
1424         assert(f);
1425
1426         if (!prefix)
1427                 prefix = "";
1428         p2 = strappend(prefix, "\t");
1429         prefix2 = p2 ? p2 : prefix;
1430
1431         cmd = exec_command_line(c->argv);
1432
1433         fprintf(f,
1434                 "%sCommand Line: %s\n",
1435                 prefix, cmd ? cmd : strerror(ENOMEM));
1436
1437         free(cmd);
1438
1439         exec_status_dump(&c->exec_status, f, prefix2);
1440
1441         free(p2);
1442 }
1443
1444 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {
1445         assert(f);
1446
1447         if (!prefix)
1448                 prefix = "";
1449
1450         LIST_FOREACH(command, c, c)
1451                 exec_command_dump(c, f, prefix);
1452 }
1453
1454 void exec_command_append_list(ExecCommand **l, ExecCommand *e) {
1455         ExecCommand *end;
1456
1457         assert(l);
1458         assert(e);
1459
1460         if (*l) {
1461                 /* It's kinda important that we keep the order here */
1462                 LIST_FIND_TAIL(ExecCommand, command, *l, end);
1463                 LIST_INSERT_AFTER(ExecCommand, command, *l, end, e);
1464         } else
1465               *l = e;
1466 }
1467
1468 int exec_command_set(ExecCommand *c, const char *path, ...) {
1469         va_list ap;
1470         char **l, *p;
1471
1472         assert(c);
1473         assert(path);
1474
1475         va_start(ap, path);
1476         l = strv_new_ap(path, ap);
1477         va_end(ap);
1478
1479         if (!l)
1480                 return -ENOMEM;
1481
1482         if (!(p = strdup(path))) {
1483                 strv_free(l);
1484                 return -ENOMEM;
1485         }
1486
1487         free(c->path);
1488         c->path = p;
1489
1490         strv_free(c->argv);
1491         c->argv = l;
1492
1493         return 0;
1494 }
1495
1496 const char* exit_status_to_string(ExitStatus status) {
1497
1498         /* We cast to int here, so that -Wenum doesn't complain that
1499          * EXIT_SUCCESS/EXIT_FAILURE aren't in the enum */
1500
1501         switch ((int) status) {
1502
1503         case EXIT_SUCCESS:
1504                 return "SUCCESS";
1505
1506         case EXIT_FAILURE:
1507                 return "FAILURE";
1508
1509         case EXIT_INVALIDARGUMENT:
1510                 return "INVALIDARGUMENT";
1511
1512         case EXIT_NOTIMPLEMENTED:
1513                 return "NOTIMPLEMENTED";
1514
1515         case EXIT_NOPERMISSION:
1516                 return "NOPERMISSION";
1517
1518         case EXIT_NOTINSTALLED:
1519                 return "NOTINSSTALLED";
1520
1521         case EXIT_NOTCONFIGURED:
1522                 return "NOTCONFIGURED";
1523
1524         case EXIT_NOTRUNNING:
1525                 return "NOTRUNNING";
1526
1527         case EXIT_CHDIR:
1528                 return "CHDIR";
1529
1530         case EXIT_NICE:
1531                 return "NICE";
1532
1533         case EXIT_FDS:
1534                 return "FDS";
1535
1536         case EXIT_EXEC:
1537                 return "EXEC";
1538
1539         case EXIT_MEMORY:
1540                 return "MEMORY";
1541
1542         case EXIT_LIMITS:
1543                 return "LIMITS";
1544
1545         case EXIT_OOM_ADJUST:
1546                 return "OOM_ADJUST";
1547
1548         case EXIT_SIGNAL_MASK:
1549                 return "SIGNAL_MASK";
1550
1551         case EXIT_STDIN:
1552                 return "STDIN";
1553
1554         case EXIT_STDOUT:
1555                 return "STDOUT";
1556
1557         case EXIT_CHROOT:
1558                 return "CHROOT";
1559
1560         case EXIT_IOPRIO:
1561                 return "IOPRIO";
1562
1563         case EXIT_TIMERSLACK:
1564                 return "TIMERSLACK";
1565
1566         case EXIT_SECUREBITS:
1567                 return "SECUREBITS";
1568
1569         case EXIT_SETSCHEDULER:
1570                 return "SETSCHEDULER";
1571
1572         case EXIT_CPUAFFINITY:
1573                 return "CPUAFFINITY";
1574
1575         case EXIT_GROUP:
1576                 return "GROUP";
1577
1578         case EXIT_USER:
1579                 return "USER";
1580
1581         case EXIT_CAPABILITIES:
1582                 return "CAPABILITIES";
1583
1584         case EXIT_CGROUP:
1585                 return "CGROUP";
1586
1587         case EXIT_SETSID:
1588                 return "SETSID";
1589
1590         case EXIT_CONFIRM:
1591                 return "CONFIRM";
1592
1593         case EXIT_STDERR:
1594                 return "STDERR";
1595
1596         default:
1597                 return NULL;
1598         }
1599 }
1600
1601 static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
1602         [EXEC_INPUT_NULL] = "null",
1603         [EXEC_INPUT_TTY] = "tty",
1604         [EXEC_INPUT_TTY_FORCE] = "tty-force",
1605         [EXEC_INPUT_TTY_FAIL] = "tty-fail",
1606         [EXEC_INPUT_SOCKET] = "socket"
1607 };
1608
1609 static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
1610         [EXEC_OUTPUT_INHERIT] = "inherit",
1611         [EXEC_OUTPUT_NULL] = "null",
1612         [EXEC_OUTPUT_TTY] = "tty",
1613         [EXEC_OUTPUT_SYSLOG] = "syslog",
1614         [EXEC_OUTPUT_KMSG] = "kmsg",
1615         [EXEC_OUTPUT_SOCKET] = "socket"
1616 };
1617
1618 DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);
1619
1620 DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput);