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
  39 #include "execute.h"
  40 #include "strv.h"
  41 #include "macro.h"
  42 #include "util.h"
  43 #include "log.h"
  44 #include "ioprio.h"
  45 #include "securebits.h"
  46 #include "cgroup.h"
  47 #include "namespace.h"
  48
  49 /* This assumes there is a 'tty' group */
  50 #define TTY_MODE 0620
  51
  52 static int shift_fds(int fds[], unsigned n_fds) {
  53         int start, restart_from;
  54
  55         if (n_fds <= 0)
  56                 return 0;
  57
  58         /* Modifies the fds array! (sorts it) */
  59
  60         assert(fds);
  61
  62         start = 0;
  63         for (;;) {
  64                 int i;
  65
  66                 restart_from = -1;
  67
  68                 for (i = start; i < (int) n_fds; i++) {
  69                         int nfd;
  70
  71                         /* Already at right index? */
  72                         if (fds[i] == i+3)
  73                                 continue;
  74
  75                         if ((nfd = fcntl(fds[i], F_DUPFD, i+3)) < 0)
  76                                 return -errno;
  77
  78                         close_nointr_nofail(fds[i]);
  79                         fds[i] = nfd;
  80
  81                         /* Hmm, the fd we wanted isn't free? Then
  82                          * let's remember that and try again from here*/
  83                         if (nfd != i+3 && restart_from < 0)
  84                                 restart_from = i;
  85                 }
  86
  87                 if (restart_from < 0)
  88                         break;
  89
  90                 start = restart_from;
  91         }
  92
  93         return 0;
  94 }
  95
  96 static int flags_fds(const int fds[], unsigned n_fds, bool nonblock) {
  97         unsigned i;
  98         int r;
  99
 100         if (n_fds <= 0)
 101                 return 0;
 102
 103         assert(fds);
 104
 105         /* Drops/Sets O_NONBLOCK and FD_CLOEXEC from the file flags */
 106
 107         for (i = 0; i < n_fds; i++) {
 108
 109                 if ((r = fd_nonblock(fds[i], nonblock)) < 0)
 110                         return r;
 111
 112                 /* We unconditionally drop FD_CLOEXEC from the fds,
 113                  * since after all we want to pass these fds to our
 114                  * children */
 115
 116                 if ((r = fd_cloexec(fds[i], false)) < 0)
 117                         return r;
 118         }
 119
 120         return 0;
 121 }
 122
 123 static const char *tty_path(const ExecContext *context) {
 124         assert(context);
 125
 126         if (context->tty_path)
 127                 return context->tty_path;
 128
 129         return "/dev/console";
 130 }
 131
 132 static int open_null_as(int flags, int nfd) {
 133         int fd, r;
 134
 135         assert(nfd >= 0);
 136
 137         if ((fd = open("/dev/null", flags|O_NOCTTY)) < 0)
 138                 return -errno;
 139
 140         if (fd != nfd) {
 141                 r = dup2(fd, nfd) < 0 ? -errno : nfd;
 142                 close_nointr_nofail(fd);
 143         } else
 144                 r = nfd;
 145
 146         return r;
 147 }
 148
 149 static int connect_logger_as(const ExecContext *context, ExecOutput output, const char *ident, int nfd) {
 150         int fd, r;
 151         union {
 152                 struct sockaddr sa;
 153                 struct sockaddr_un un;
 154         } sa;
 155
 156         assert(context);
 157         assert(output < _EXEC_OUTPUT_MAX);
 158         assert(ident);
 159         assert(nfd >= 0);
 160
 161         if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
 162                 return -errno;
 163
 164         zero(sa);
 165         sa.sa.sa_family = AF_UNIX;
 166         strncpy(sa.un.sun_path+1, LOGGER_SOCKET, sizeof(sa.un.sun_path)-1);
 167
 168         if (connect(fd, &sa.sa, sizeof(sa)) < 0) {
 169                 close_nointr_nofail(fd);
 170                 return -errno;
 171         }
 172
 173         if (shutdown(fd, SHUT_RD) < 0) {
 174                 close_nointr_nofail(fd);
 175                 return -errno;
 176         }
 177
 178         /* We speak a very simple protocol between log server
 179          * and client: one line for the log destination (kmsg
 180          * or syslog), followed by the priority field,
 181          * followed by the process name. Since we replaced
 182          * stdin/stderr we simple use stdio to write to
 183          * it. Note that we use stderr, to minimize buffer
 184          * flushing issues. */
 185
 186         dprintf(fd,
 187                 "%s\n"
 188                 "%i\n"
 189                 "%s\n",
 190                 output == EXEC_OUTPUT_KERNEL ? "kmsg" : "syslog",
 191                 context->syslog_priority,
 192                 context->syslog_identifier ? context->syslog_identifier : ident);
 193
 194         if (fd != nfd) {
 195                 r = dup2(fd, nfd) < 0 ? -errno : nfd;
 196                 close_nointr_nofail(fd);
 197         } else
 198                 r = nfd;
 199
 200         return r;
 201 }
 202 static int open_terminal_as(const char *path, mode_t mode, int nfd) {
 203         int fd, r;
 204
 205         assert(path);
 206         assert(nfd >= 0);
 207
 208         if ((fd = open_terminal(path, mode | O_NOCTTY)) < 0)
 209                 return fd;
 210
 211         if (fd != nfd) {
 212                 r = dup2(fd, nfd) < 0 ? -errno : nfd;
 213                 close_nointr_nofail(fd);
 214         } else
 215                 r = nfd;
 216
 217         return r;
 218 }
 219
 220 static bool is_terminal_input(ExecInput i) {
 221         return
 222                 i == EXEC_INPUT_TTY ||
 223                 i == EXEC_INPUT_TTY_FORCE ||
 224                 i == EXEC_INPUT_TTY_FAIL;
 225 }
 226
 227 static int fixup_input(const ExecContext *context, int socket_fd) {
 228         assert(context);
 229
 230         if (socket_fd < 0 && context->std_input == EXEC_INPUT_SOCKET)
 231                 return EXEC_INPUT_NULL;
 232
 233         return context->std_input;
 234 }
 235
 236 static int fixup_output(const ExecContext *context, int socket_fd) {
 237         assert(context);
 238
 239         if (socket_fd < 0 && context->std_output == EXEC_OUTPUT_SOCKET)
 240                 return EXEC_OUTPUT_INHERIT;
 241
 242         return context->std_output;
 243 }
 244
 245 static int fixup_error(const ExecContext *context, int socket_fd) {
 246         assert(context);
 247
 248         if (socket_fd < 0 && context->std_error == EXEC_OUTPUT_SOCKET)
 249                 return EXEC_OUTPUT_INHERIT;
 250
 251         return context->std_error;
 252 }
 253
 254 static int setup_input(const ExecContext *context, int socket_fd) {
 255         ExecInput i;
 256
 257         assert(context);
 258
 259         i = fixup_input(context, socket_fd);
 260
 261         switch (i) {
 262
 263         case EXEC_INPUT_NULL:
 264                 return open_null_as(O_RDONLY, STDIN_FILENO);
 265
 266         case EXEC_INPUT_TTY:
 267         case EXEC_INPUT_TTY_FORCE:
 268         case EXEC_INPUT_TTY_FAIL: {
 269                 int fd, r;
 270
 271                 if ((fd = acquire_terminal(
 272                                      tty_path(context),
 273                                      i == EXEC_INPUT_TTY_FAIL,
 274                                      i == EXEC_INPUT_TTY_FORCE)) < 0)
 275                         return fd;
 276
 277                 if (fd != STDIN_FILENO) {
 278                         r = dup2(fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
 279                         close_nointr_nofail(fd);
 280                 } else
 281                         r = STDIN_FILENO;
 282
 283                 return r;
 284         }
 285
 286         case EXEC_INPUT_SOCKET:
 287                 return dup2(socket_fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
 288
 289         default:
 290                 assert_not_reached("Unknown input type");
 291         }
 292 }
 293
 294 static int setup_output(const ExecContext *context, int socket_fd, const char *ident) {
 295         ExecOutput o;
 296         ExecInput i;
 297
 298         assert(context);
 299         assert(ident);
 300
 301         i = fixup_input(context, socket_fd);
 302         o = fixup_output(context, socket_fd);
 303
 304         /* This expects the input is already set up */
 305
 306         switch (o) {
 307
 308         case EXEC_OUTPUT_INHERIT:
 309
 310                 /* If the input is connected to a terminal, inherit that... */
 311                 if (is_terminal_input(i) || i == EXEC_INPUT_SOCKET)
 312                         return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
 313
 314                 return STDIN_FILENO;
 315
 316         case EXEC_OUTPUT_NULL:
 317                 return open_null_as(O_WRONLY, STDOUT_FILENO);
 318
 319         case EXEC_OUTPUT_TTY:
 320                 if (is_terminal_input(i))
 321                         return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
 322
 323                 /* We don't reset the terminal if this is just about output */
 324                 return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
 325
 326         case EXEC_OUTPUT_SYSLOG:
 327         case EXEC_OUTPUT_KERNEL:
 328                 return connect_logger_as(context, o, ident, STDOUT_FILENO);
 329
 330         case EXEC_OUTPUT_SOCKET:
 331                 assert(socket_fd >= 0);
 332                 return dup2(socket_fd, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
 333
 334         default:
 335                 assert_not_reached("Unknown output type");
 336         }
 337 }
 338
 339 static int setup_error(const ExecContext *context, int socket_fd, const char *ident) {
 340         ExecOutput o, e;
 341         ExecInput i;
 342
 343         assert(context);
 344         assert(ident);
 345
 346         i = fixup_input(context, socket_fd);
 347         o = fixup_output(context, socket_fd);
 348         e = fixup_error(context, socket_fd);
 349
 350         /* This expects the input and output are already set up */
 351
 352         /* Don't change the stderr file descriptor if we inherit all
 353          * the way and are not on a tty */
 354         if (e == EXEC_OUTPUT_INHERIT &&
 355             o == EXEC_OUTPUT_INHERIT &&
 356             !is_terminal_input(i))
 357                 return STDERR_FILENO;
 358
 359         /* Duplicate form stdout if possible */
 360         if (e == o || e == EXEC_OUTPUT_INHERIT)
 361                 return dup2(STDOUT_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
 362
 363         switch (e) {
 364
 365         case EXEC_OUTPUT_NULL:
 366                 return open_null_as(O_WRONLY, STDERR_FILENO);
 367
 368         case EXEC_OUTPUT_TTY:
 369                 if (is_terminal_input(i))
 370                         return dup2(STDIN_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
 371
 372                 /* We don't reset the terminal if this is just about output */
 373                 return open_terminal_as(tty_path(context), O_WRONLY, STDERR_FILENO);
 374
 375         case EXEC_OUTPUT_SYSLOG:
 376         case EXEC_OUTPUT_KERNEL:
 377                 return connect_logger_as(context, e, ident, STDERR_FILENO);
 378
 379         case EXEC_OUTPUT_SOCKET:
 380                 assert(socket_fd >= 0);
 381                 return dup2(socket_fd, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
 382
 383         default:
 384                 assert_not_reached("Unknown error type");
 385         }
 386 }
 387
 388 static int chown_terminal(int fd, uid_t uid) {
 389         struct stat st;
 390
 391         assert(fd >= 0);
 392
 393         /* This might fail. What matters are the results. */
 394         fchown(fd, uid, -1);
 395         fchmod(fd, TTY_MODE);
 396
 397         if (fstat(fd, &st) < 0)
 398                 return -errno;
 399
 400         if (st.st_uid != uid || (st.st_mode & 0777) != TTY_MODE)
 401                 return -EPERM;
 402
 403         return 0;
 404 }
 405
 406 static int setup_confirm_stdio(const ExecContext *context,
 407                                int *_saved_stdin,
 408                                int *_saved_stdout) {
 409         int fd = -1, saved_stdin, saved_stdout = -1, r;
 410
 411         assert(context);
 412         assert(_saved_stdin);
 413         assert(_saved_stdout);
 414
 415         /* This returns positive EXIT_xxx return values instead of
 416          * negative errno style values! */
 417
 418         if ((saved_stdin = fcntl(STDIN_FILENO, F_DUPFD, 3)) < 0)
 419                 return EXIT_STDIN;
 420
 421         if ((saved_stdout = fcntl(STDOUT_FILENO, F_DUPFD, 3)) < 0) {
 422                 r = EXIT_STDOUT;
 423                 goto fail;
 424         }
 425
 426         if ((fd = acquire_terminal(
 427                              tty_path(context),
 428                              context->std_input == EXEC_INPUT_TTY_FAIL,
 429                              context->std_input == EXEC_INPUT_TTY_FORCE)) < 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                bool apply_permissions,
 727                bool apply_chroot,
 728                bool confirm_spawn,
 729                CGroupBonding *cgroup_bondings,
 730                pid_t *ret) {
 731
 732         pid_t pid;
 733         int r;
 734         char *line;
 735         int socket_fd;
 736
 737         assert(command);
 738         assert(context);
 739         assert(ret);
 740         assert(fds || n_fds <= 0);
 741
 742         if (context->std_input == EXEC_INPUT_SOCKET ||
 743             context->std_output == EXEC_OUTPUT_SOCKET ||
 744             context->std_error == EXEC_OUTPUT_SOCKET) {
 745
 746                 if (n_fds != 1)
 747                         return -EINVAL;
 748
 749                 socket_fd = fds[0];
 750
 751                 fds = NULL;
 752                 n_fds = 0;
 753         } else
 754                 socket_fd = -1;
 755
 756         if (!argv)
 757                 argv = command->argv;
 758
 759         if (!(line = exec_command_line(argv)))
 760                 return -ENOMEM;
 761
 762         log_debug("About to execute: %s", line);
 763         free(line);
 764
 765         if (cgroup_bondings)
 766                 if ((r = cgroup_bonding_realize_list(cgroup_bondings)))
 767                         return r;
 768
 769         if ((pid = fork()) < 0)
 770                 return -errno;
 771
 772         if (pid == 0) {
 773                 int i;
 774                 sigset_t ss;
 775                 const char *username = NULL, *home = NULL;
 776                 uid_t uid = (uid_t) -1;
 777                 gid_t gid = (gid_t) -1;
 778                 char **our_env = NULL, **final_env = NULL;
 779                 unsigned n_env = 0;
 780                 int saved_stdout = -1, saved_stdin = -1;
 781                 bool keep_stdout = false, keep_stdin = false;
 782
 783                 /* child */
 784
 785                 reset_all_signal_handlers();
 786
 787                 if (sigemptyset(&ss) < 0 ||
 788                     sigprocmask(SIG_SETMASK, &ss, NULL) < 0) {
 789                         r = EXIT_SIGNAL_MASK;
 790                         goto fail;
 791                 }
 792
 793                 if (!context->no_setsid)
 794                         if (setsid() < 0) {
 795                                 r = EXIT_SETSID;
 796                                 goto fail;
 797                         }
 798
 799                 if (confirm_spawn) {
 800                         char response;
 801
 802                         /* Set up terminal for the question */
 803                         if ((r = setup_confirm_stdio(context,
 804                                                      &saved_stdin, &saved_stdout)))
 805                                 goto fail;
 806
 807                         /* Now ask the question. */
 808                         if (!(line = exec_command_line(argv))) {
 809                                 r = EXIT_MEMORY;
 810                                 goto fail;
 811                         }
 812
 813                         r = ask(&response, "yns", "Execute %s? [Yes, No, Skip] ", line);
 814                         free(line);
 815
 816                         if (r < 0 || response == 'n') {
 817                                 r = EXIT_CONFIRM;
 818                                 goto fail;
 819                         } else if (response == 's') {
 820                                 r = 0;
 821                                 goto fail;
 822                         }
 823
 824                         /* Release terminal for the question */
 825                         if ((r = restore_confirm_stdio(context,
 826                                                        &saved_stdin, &saved_stdout,
 827                                                        &keep_stdin, &keep_stdout)))
 828                                 goto fail;
 829                 }
 830
 831                 if (!keep_stdin)
 832                         if (setup_input(context, socket_fd) < 0) {
 833                                 r = EXIT_STDIN;
 834                                 goto fail;
 835                         }
 836
 837                 if (!keep_stdout)
 838                         if (setup_output(context, socket_fd, file_name_from_path(command->path)) < 0) {
 839                                 r = EXIT_STDOUT;
 840                                 goto fail;
 841                         }
 842
 843                 if (setup_error(context, socket_fd, file_name_from_path(command->path)) < 0) {
 844                         r = EXIT_STDERR;
 845                         goto fail;
 846                 }
 847
 848                 if (cgroup_bondings)
 849                         if ((r = cgroup_bonding_install_list(cgroup_bondings, 0)) < 0) {
 850                                 r = EXIT_CGROUP;
 851                                 goto fail;
 852                         }
 853
 854                 if (context->oom_adjust_set) {
 855                         char t[16];
 856
 857                         snprintf(t, sizeof(t), "%i", context->oom_adjust);
 858                         char_array_0(t);
 859
 860                         if (write_one_line_file("/proc/self/oom_adj", t) < 0) {
 861                                 r = EXIT_OOM_ADJUST;
 862                                 goto fail;
 863                         }
 864                 }
 865
 866                 if (context->nice_set)
 867                         if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
 868                                 r = EXIT_NICE;
 869                                 goto fail;
 870                         }
 871
 872                 if (context->cpu_sched_set) {
 873                         struct sched_param param;
 874
 875                         zero(param);
 876                         param.sched_priority = context->cpu_sched_priority;
 877
 878                         if (sched_setscheduler(0, context->cpu_sched_policy |
 879                                                (context->cpu_sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0), &param) < 0) {
 880                                 r = EXIT_SETSCHEDULER;
 881                                 goto fail;
 882                         }
 883                 }
 884
 885                 if (context->cpu_affinity_set)
 886                         if (sched_setaffinity(0, sizeof(context->cpu_affinity), &context->cpu_affinity) < 0) {
 887                                 r = EXIT_CPUAFFINITY;
 888                                 goto fail;
 889                         }
 890
 891                 if (context->ioprio_set)
 892                         if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
 893                                 r = EXIT_IOPRIO;
 894                                 goto fail;
 895                         }
 896
 897                 if (context->timer_slack_ns_set)
 898                         if (prctl(PR_SET_TIMERSLACK, context->timer_slack_ns_set) < 0) {
 899                                 r = EXIT_TIMERSLACK;
 900                                 goto fail;
 901                         }
 902
 903                 if (strv_length(context->read_write_dirs) > 0 ||
 904                     strv_length(context->read_only_dirs) > 0 ||
 905                     strv_length(context->inaccessible_dirs) > 0 ||
 906                     context->mount_flags != MS_SHARED ||
 907                     context->private_tmp)
 908                         if ((r = setup_namespace(
 909                                              context->read_write_dirs,
 910                                              context->read_only_dirs,
 911                                              context->inaccessible_dirs,
 912                                              context->private_tmp,
 913                                              context->mount_flags)) < 0)
 914                                 goto fail;
 915
 916                 if (context->user) {
 917                         username = context->user;
 918                         if (get_user_creds(&username, &uid, &gid, &home) < 0) {
 919                                 r = EXIT_USER;
 920                                 goto fail;
 921                         }
 922
 923                         if (is_terminal_input(context->std_input))
 924                                 if (chown_terminal(STDIN_FILENO, uid) < 0) {
 925                                         r = EXIT_STDIN;
 926                                         goto fail;
 927                                 }
 928                 }
 929
 930                 if (apply_permissions)
 931                         if (enforce_groups(context, username, uid) < 0) {
 932                                 r = EXIT_GROUP;
 933                                 goto fail;
 934                         }
 935
 936                 umask(context->umask);
 937
 938                 if (apply_chroot) {
 939                         if (context->root_directory)
 940                                 if (chroot(context->root_directory) < 0) {
 941                                         r = EXIT_CHROOT;
 942                                         goto fail;
 943                                 }
 944
 945                         if (chdir(context->working_directory ? context->working_directory : "/") < 0) {
 946                                 r = EXIT_CHDIR;
 947                                 goto fail;
 948                         }
 949                 } else {
 950
 951                         char *d;
 952
 953                         if (asprintf(&d, "%s/%s",
 954                                      context->root_directory ? context->root_directory : "",
 955                                      context->working_directory ? context->working_directory : "") < 0) {
 956                                 r = EXIT_MEMORY;
 957                                 goto fail;
 958                         }
 959
 960                         if (chdir(d) < 0) {
 961                                 free(d);
 962                                 r = EXIT_CHDIR;
 963                                 goto fail;
 964                         }
 965
 966                         free(d);
 967                 }
 968
 969                 if (close_all_fds(fds, n_fds) < 0 ||
 970                     shift_fds(fds, n_fds) < 0 ||
 971                     flags_fds(fds, n_fds, context->non_blocking) < 0) {
 972                         r = EXIT_FDS;
 973                         goto fail;
 974                 }
 975
 976                 if (apply_permissions) {
 977
 978                         for (i = 0; i < RLIMIT_NLIMITS; i++) {
 979                                 if (!context->rlimit[i])
 980                                         continue;
 981
 982                                 if (setrlimit(i, context->rlimit[i]) < 0) {
 983                                         r = EXIT_LIMITS;
 984                                         goto fail;
 985                                 }
 986                         }
 987
 988                         if (context->user)
 989                                 if (enforce_user(context, uid) < 0) {
 990                                         r = EXIT_USER;
 991                                         goto fail;
 992                                 }
 993
 994                         /* PR_GET_SECUREBITS is not priviliged, while
 995                          * PR_SET_SECUREBITS is. So to suppress
 996                          * potential EPERMs we'll try not to call
 997                          * PR_SET_SECUREBITS unless necessary. */
 998                         if (prctl(PR_GET_SECUREBITS) != context->secure_bits)
 999                                 if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {
1000                                         r = EXIT_SECUREBITS;
1001                                         goto fail;
1002                                 }
1003
1004                         if (context->capabilities)
1005                                 if (cap_set_proc(context->capabilities) < 0) {
1006                                         r = EXIT_CAPABILITIES;
1007                                         goto fail;
1008                                 }
1009                 }
1010
1011                 if (!(our_env = new0(char*, 6))) {
1012                         r = EXIT_MEMORY;
1013                         goto fail;
1014                 }
1015
1016                 if (n_fds > 0)
1017                         if (asprintf(our_env + n_env++, "LISTEN_PID=%llu", (unsigned long long) getpid()) < 0 ||
1018                             asprintf(our_env + n_env++, "LISTEN_FDS=%u", n_fds) < 0) {
1019                                 r = EXIT_MEMORY;
1020                                 goto fail;
1021                         }
1022
1023                 if (home)
1024                         if (asprintf(our_env + n_env++, "HOME=%s", home) < 0) {
1025                                 r = EXIT_MEMORY;
1026                                 goto fail;
1027                         }
1028
1029                 if (username)
1030                         if (asprintf(our_env + n_env++, "LOGNAME=%s", username) < 0 ||
1031                             asprintf(our_env + n_env++, "USER=%s", username) < 0) {
1032                                 r = EXIT_MEMORY;
1033                                 goto fail;
1034                         }
1035
1036                 if (!(final_env = strv_env_merge(environ, our_env, context->environment, NULL))) {
1037                         r = EXIT_MEMORY;
1038                         goto fail;
1039                 }
1040
1041                 execve(command->path, argv, final_env);
1042                 r = EXIT_EXEC;
1043
1044         fail:
1045                 strv_free(our_env);
1046                 strv_free(final_env);
1047
1048                 if (saved_stdin >= 0)
1049                         close_nointr_nofail(saved_stdin);
1050
1051                 if (saved_stdout >= 0)
1052                         close_nointr_nofail(saved_stdout);
1053
1054                 _exit(r);
1055         }
1056
1057         /* We add the new process to the cgroup both in the child (so
1058          * that we can be sure that no user code is ever executed
1059          * outside of the cgroup) and in the parent (so that we can be
1060          * sure that when we kill the cgroup the process will be
1061          * killed too). */
1062         if (cgroup_bondings)
1063                 if ((r = cgroup_bonding_install_list(cgroup_bondings, pid)) < 0) {
1064                         r = EXIT_CGROUP;
1065                         goto fail;
1066                 }
1067
1068         log_debug("Forked %s as %llu", command->path, (unsigned long long) pid);
1069
1070         command->exec_status.pid = pid;
1071         command->exec_status.start_timestamp = now(CLOCK_REALTIME);
1072
1073         *ret = pid;
1074         return 0;
1075 }
1076
1077 void exec_context_init(ExecContext *c) {
1078         assert(c);
1079
1080         c->umask = 0002;
1081         c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
1082         c->cpu_sched_policy = SCHED_OTHER;
1083         c->syslog_priority = LOG_DAEMON|LOG_INFO;
1084         c->mount_flags = MS_SHARED;
1085 }
1086
1087 void exec_context_done(ExecContext *c) {
1088         unsigned l;
1089
1090         assert(c);
1091
1092         strv_free(c->environment);
1093         c->environment = NULL;
1094
1095         for (l = 0; l < ELEMENTSOF(c->rlimit); l++) {
1096                 free(c->rlimit[l]);
1097                 c->rlimit[l] = NULL;
1098         }
1099
1100         free(c->working_directory);
1101         c->working_directory = NULL;
1102         free(c->root_directory);
1103         c->root_directory = NULL;
1104
1105         free(c->tty_path);
1106         c->tty_path = NULL;
1107
1108         free(c->syslog_identifier);
1109         c->syslog_identifier = NULL;
1110
1111         free(c->user);
1112         c->user = NULL;
1113
1114         free(c->group);
1115         c->group = NULL;
1116
1117         strv_free(c->supplementary_groups);
1118         c->supplementary_groups = NULL;
1119
1120         if (c->capabilities) {
1121                 cap_free(c->capabilities);
1122                 c->capabilities = NULL;
1123         }
1124
1125         strv_free(c->read_only_dirs);
1126         c->read_only_dirs = NULL;
1127
1128         strv_free(c->read_write_dirs);
1129         c->read_write_dirs = NULL;
1130
1131         strv_free(c->inaccessible_dirs);
1132         c->inaccessible_dirs = NULL;
1133 }
1134
1135 void exec_command_done(ExecCommand *c) {
1136         assert(c);
1137
1138         free(c->path);
1139         c->path = NULL;
1140
1141         strv_free(c->argv);
1142         c->argv = NULL;
1143 }
1144
1145 void exec_command_done_array(ExecCommand *c, unsigned n) {
1146         unsigned i;
1147
1148         for (i = 0; i < n; i++)
1149                 exec_command_done(c+i);
1150 }
1151
1152 void exec_command_free_list(ExecCommand *c) {
1153         ExecCommand *i;
1154
1155         while ((i = c)) {
1156                 LIST_REMOVE(ExecCommand, command, c, i);
1157                 exec_command_done(i);
1158                 free(i);
1159         }
1160 }
1161
1162 void exec_command_free_array(ExecCommand **c, unsigned n) {
1163         unsigned i;
1164
1165         for (i = 0; i < n; i++) {
1166                 exec_command_free_list(c[i]);
1167                 c[i] = NULL;
1168         }
1169 }
1170
1171 static void strv_fprintf(FILE *f, char **l) {
1172         char **g;
1173
1174         assert(f);
1175
1176         STRV_FOREACH(g, l)
1177                 fprintf(f, " %s", *g);
1178 }
1179
1180 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
1181         char ** e;
1182         unsigned i;
1183
1184         assert(c);
1185         assert(f);
1186
1187         if (!prefix)
1188                 prefix = "";
1189
1190         fprintf(f,
1191                 "%sUMask: %04o\n"
1192                 "%sWorkingDirectory: %s\n"
1193                 "%sRootDirectory: %s\n"
1194                 "%sNonBlocking: %s\n"
1195                 "%sPrivateTmp: %s\n",
1196                 prefix, c->umask,
1197                 prefix, c->working_directory ? c->working_directory : "/",
1198                 prefix, c->root_directory ? c->root_directory : "/",
1199                 prefix, yes_no(c->non_blocking),
1200                 prefix, yes_no(c->private_tmp));
1201
1202         if (c->environment)
1203                 for (e = c->environment; *e; e++)
1204                         fprintf(f, "%sEnvironment: %s\n", prefix, *e);
1205
1206         if (c->nice_set)
1207                 fprintf(f,
1208                         "%sNice: %i\n",
1209                         prefix, c->nice);
1210
1211         if (c->oom_adjust_set)
1212                 fprintf(f,
1213                         "%sOOMAdjust: %i\n",
1214                         prefix, c->oom_adjust);
1215
1216         for (i = 0; i < RLIM_NLIMITS; i++)
1217                 if (c->rlimit[i])
1218                         fprintf(f, "%s%s: %llu\n", prefix, rlimit_to_string(i), (unsigned long long) c->rlimit[i]->rlim_max);
1219
1220         if (c->ioprio_set)
1221                 fprintf(f,
1222                         "%sIOSchedulingClass: %s\n"
1223                         "%sIOPriority: %i\n",
1224                         prefix, ioprio_class_to_string(IOPRIO_PRIO_CLASS(c->ioprio)),
1225                         prefix, (int) IOPRIO_PRIO_DATA(c->ioprio));
1226
1227         if (c->cpu_sched_set)
1228                 fprintf(f,
1229                         "%sCPUSchedulingPolicy: %s\n"
1230                         "%sCPUSchedulingPriority: %i\n"
1231                         "%sCPUSchedulingResetOnFork: %s\n",
1232                         prefix, sched_policy_to_string(c->cpu_sched_policy),
1233                         prefix, c->cpu_sched_priority,
1234                         prefix, yes_no(c->cpu_sched_reset_on_fork));
1235
1236         if (c->cpu_affinity_set) {
1237                 fprintf(f, "%sCPUAffinity:", prefix);
1238                 for (i = 0; i < CPU_SETSIZE; i++)
1239                         if (CPU_ISSET(i, &c->cpu_affinity))
1240                                 fprintf(f, " %i", i);
1241                 fputs("\n", f);
1242         }
1243
1244         if (c->timer_slack_ns_set)
1245                 fprintf(f, "%sTimerSlackNS: %lu\n", prefix, c->timer_slack_ns);
1246
1247         fprintf(f,
1248                 "%sStandardInput: %s\n"
1249                 "%sStandardOutput: %s\n"
1250                 "%sStandardError: %s\n",
1251                 prefix, exec_input_to_string(c->std_input),
1252                 prefix, exec_output_to_string(c->std_output),
1253                 prefix, exec_output_to_string(c->std_error));
1254
1255         if (c->tty_path)
1256                 fprintf(f,
1257                         "%sTTYPath: %s\n",
1258                         prefix, c->tty_path);
1259
1260         if (c->std_output == EXEC_OUTPUT_SYSLOG || c->std_output == EXEC_OUTPUT_KERNEL ||
1261             c->std_error == EXEC_OUTPUT_SYSLOG || c->std_error == EXEC_OUTPUT_KERNEL)
1262                 fprintf(f,
1263                         "%sSyslogFacility: %s\n"
1264                         "%sSyslogLevel: %s\n",
1265                         prefix, log_facility_to_string(LOG_FAC(c->syslog_priority)),
1266                         prefix, log_level_to_string(LOG_PRI(c->syslog_priority)));
1267
1268         if (c->capabilities) {
1269                 char *t;
1270                 if ((t = cap_to_text(c->capabilities, NULL))) {
1271                         fprintf(f, "%sCapabilities: %s\n",
1272                                 prefix, t);
1273                         cap_free(t);
1274                 }
1275         }
1276
1277         if (c->secure_bits)
1278                 fprintf(f, "%sSecure Bits:%s%s%s%s%s%s\n",
1279                         prefix,
1280                         (c->secure_bits & SECURE_KEEP_CAPS) ? " keep-caps" : "",
1281                         (c->secure_bits & SECURE_KEEP_CAPS_LOCKED) ? " keep-caps-locked" : "",
1282                         (c->secure_bits & SECURE_NO_SETUID_FIXUP) ? " no-setuid-fixup" : "",
1283                         (c->secure_bits & SECURE_NO_SETUID_FIXUP_LOCKED) ? " no-setuid-fixup-locked" : "",
1284                         (c->secure_bits & SECURE_NOROOT) ? " noroot" : "",
1285                         (c->secure_bits & SECURE_NOROOT_LOCKED) ? "noroot-locked" : "");
1286
1287         if (c->capability_bounding_set_drop) {
1288                 fprintf(f, "%sCapabilityBoundingSetDrop:", prefix);
1289
1290                 for (i = 0; i <= CAP_LAST_CAP; i++)
1291                         if (c->capability_bounding_set_drop & (1 << i)) {
1292                                 char *t;
1293
1294                                 if ((t = cap_to_name(i))) {
1295                                         fprintf(f, " %s", t);
1296                                         free(t);
1297                                 }
1298                         }
1299
1300                 fputs("\n", f);
1301         }
1302
1303         if (c->user)
1304                 fprintf(f, "%sUser: %s", prefix, c->user);
1305         if (c->group)
1306                 fprintf(f, "%sGroup: %s", prefix, c->group);
1307
1308         if (strv_length(c->supplementary_groups) > 0) {
1309                 fprintf(f, "%sSupplementaryGroups:", prefix);
1310                 strv_fprintf(f, c->supplementary_groups);
1311                 fputs("\n", f);
1312         }
1313
1314         if (strv_length(c->read_write_dirs) > 0) {
1315                 fprintf(f, "%sReadWriteDirs:", prefix);
1316                 strv_fprintf(f, c->read_write_dirs);
1317                 fputs("\n", f);
1318         }
1319
1320         if (strv_length(c->read_only_dirs) > 0) {
1321                 fprintf(f, "%sReadOnlyDirs:", prefix);
1322                 strv_fprintf(f, c->read_only_dirs);
1323                 fputs("\n", f);
1324         }
1325
1326         if (strv_length(c->inaccessible_dirs) > 0) {
1327                 fprintf(f, "%sInaccessibleDirs:", prefix);
1328                 strv_fprintf(f, c->inaccessible_dirs);
1329                 fputs("\n", f);
1330         }
1331 }
1332
1333 void exec_status_fill(ExecStatus *s, pid_t pid, int code, int status) {
1334         assert(s);
1335
1336         s->pid = pid;
1337         s->exit_timestamp = now(CLOCK_REALTIME);
1338
1339         s->code = code;
1340         s->status = status;
1341 }
1342
1343 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix) {
1344         char buf[FORMAT_TIMESTAMP_MAX];
1345
1346         assert(s);
1347         assert(f);
1348
1349         if (!prefix)
1350                 prefix = "";
1351
1352         if (s->pid <= 0)
1353                 return;
1354
1355         fprintf(f,
1356                 "%sPID: %llu\n",
1357                 prefix, (unsigned long long) s->pid);
1358
1359         if (s->start_timestamp > 0)
1360                 fprintf(f,
1361                         "%sStart Timestamp: %s\n",
1362                         prefix, format_timestamp(buf, sizeof(buf), s->start_timestamp));
1363
1364         if (s->exit_timestamp > 0)
1365                 fprintf(f,
1366                         "%sExit Timestamp: %s\n"
1367                         "%sExit Code: %s\n"
1368                         "%sExit Status: %i\n",
1369                         prefix, format_timestamp(buf, sizeof(buf), s->exit_timestamp),
1370                         prefix, sigchld_code_to_string(s->code),
1371                         prefix, s->status);
1372 }
1373
1374 char *exec_command_line(char **argv) {
1375         size_t k;
1376         char *n, *p, **a;
1377         bool first = true;
1378
1379         assert(argv);
1380
1381         k = 1;
1382         STRV_FOREACH(a, argv)
1383                 k += strlen(*a)+3;
1384
1385         if (!(n = new(char, k)))
1386                 return NULL;
1387
1388         p = n;
1389         STRV_FOREACH(a, argv) {
1390
1391                 if (!first)
1392                         *(p++) = ' ';
1393                 else
1394                         first = false;
1395
1396                 if (strpbrk(*a, WHITESPACE)) {
1397                         *(p++) = '\'';
1398                         p = stpcpy(p, *a);
1399                         *(p++) = '\'';
1400                 } else
1401                         p = stpcpy(p, *a);
1402
1403         }
1404
1405         *p = 0;
1406
1407         /* FIXME: this doesn't really handle arguments that have
1408          * spaces and ticks in them */
1409
1410         return n;
1411 }
1412
1413 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
1414         char *p2;
1415         const char *prefix2;
1416
1417         char *cmd;
1418
1419         assert(c);
1420         assert(f);
1421
1422         if (!prefix)
1423                 prefix = "";
1424         p2 = strappend(prefix, "\t");
1425         prefix2 = p2 ? p2 : prefix;
1426
1427         cmd = exec_command_line(c->argv);
1428
1429         fprintf(f,
1430                 "%sCommand Line: %s\n",
1431                 prefix, cmd ? cmd : strerror(ENOMEM));
1432
1433         free(cmd);
1434
1435         exec_status_dump(&c->exec_status, f, prefix2);
1436
1437         free(p2);
1438 }
1439
1440 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {
1441         assert(f);
1442
1443         if (!prefix)
1444                 prefix = "";
1445
1446         LIST_FOREACH(command, c, c)
1447                 exec_command_dump(c, f, prefix);
1448 }
1449
1450 void exec_command_append_list(ExecCommand **l, ExecCommand *e) {
1451         ExecCommand *end;
1452
1453         assert(l);
1454         assert(e);
1455
1456         if (*l) {
1457                 /* It's kinda important that we keep the order here */
1458                 LIST_FIND_TAIL(ExecCommand, command, *l, end);
1459                 LIST_INSERT_AFTER(ExecCommand, command, *l, end, e);
1460         } else
1461               *l = e;
1462 }
1463
1464 int exec_command_set(ExecCommand *c, const char *path, ...) {
1465         va_list ap;
1466         char **l, *p;
1467
1468         assert(c);
1469         assert(path);
1470
1471         va_start(ap, path);
1472         l = strv_new_ap(path, ap);
1473         va_end(ap);
1474
1475         if (!l)
1476                 return -ENOMEM;
1477
1478         if (!(p = strdup(path))) {
1479                 strv_free(l);
1480                 return -ENOMEM;
1481         }
1482
1483         free(c->path);
1484         c->path = p;
1485
1486         strv_free(c->argv);
1487         c->argv = l;
1488
1489         return 0;
1490 }
1491
1492 const char* exit_status_to_string(ExitStatus status) {
1493
1494         /* We cast to int here, so that -Wenum doesn't complain that
1495          * EXIT_SUCCESS/EXIT_FAILURE aren't in the enum */
1496
1497         switch ((int) status) {
1498
1499         case EXIT_SUCCESS:
1500                 return "SUCCESS";
1501
1502         case EXIT_FAILURE:
1503                 return "FAILURE";
1504
1505         case EXIT_INVALIDARGUMENT:
1506                 return "INVALIDARGUMENT";
1507
1508         case EXIT_NOTIMPLEMENTED:
1509                 return "NOTIMPLEMENTED";
1510
1511         case EXIT_NOPERMISSION:
1512                 return "NOPERMISSION";
1513
1514         case EXIT_NOTINSTALLED:
1515                 return "NOTINSSTALLED";
1516
1517         case EXIT_NOTCONFIGURED:
1518                 return "NOTCONFIGURED";
1519
1520         case EXIT_NOTRUNNING:
1521                 return "NOTRUNNING";
1522
1523         case EXIT_CHDIR:
1524                 return "CHDIR";
1525
1526         case EXIT_NICE:
1527                 return "NICE";
1528
1529         case EXIT_FDS:
1530                 return "FDS";
1531
1532         case EXIT_EXEC:
1533                 return "EXEC";
1534
1535         case EXIT_MEMORY:
1536                 return "MEMORY";
1537
1538         case EXIT_LIMITS:
1539                 return "LIMITS";
1540
1541         case EXIT_OOM_ADJUST:
1542                 return "OOM_ADJUST";
1543
1544         case EXIT_SIGNAL_MASK:
1545                 return "SIGNAL_MASK";
1546
1547         case EXIT_STDIN:
1548                 return "STDIN";
1549
1550         case EXIT_STDOUT:
1551                 return "STDOUT";
1552
1553         case EXIT_CHROOT:
1554                 return "CHROOT";
1555
1556         case EXIT_IOPRIO:
1557                 return "IOPRIO";
1558
1559         case EXIT_TIMERSLACK:
1560                 return "TIMERSLACK";
1561
1562         case EXIT_SECUREBITS:
1563                 return "SECUREBITS";
1564
1565         case EXIT_SETSCHEDULER:
1566                 return "SETSCHEDULER";
1567
1568         case EXIT_CPUAFFINITY:
1569                 return "CPUAFFINITY";
1570
1571         case EXIT_GROUP:
1572                 return "GROUP";
1573
1574         case EXIT_USER:
1575                 return "USER";
1576
1577         case EXIT_CAPABILITIES:
1578                 return "CAPABILITIES";
1579
1580         case EXIT_CGROUP:
1581                 return "CGROUP";
1582
1583         case EXIT_SETSID:
1584                 return "SETSID";
1585
1586         case EXIT_CONFIRM:
1587                 return "CONFIRM";
1588
1589         case EXIT_STDERR:
1590                 return "STDERR";
1591
1592         default:
1593                 return NULL;
1594         }
1595 }
1596
1597 static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
1598         [EXEC_INPUT_NULL] = "null",
1599         [EXEC_INPUT_TTY] = "tty",
1600         [EXEC_INPUT_TTY_FORCE] = "tty-force",
1601         [EXEC_INPUT_TTY_FAIL] = "tty-fail",
1602         [EXEC_INPUT_SOCKET] = "socket"
1603 };
1604
1605 static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
1606         [EXEC_OUTPUT_INHERIT] = "inherit",
1607         [EXEC_OUTPUT_NULL] = "null",
1608         [EXEC_OUTPUT_TTY] = "tty",
1609         [EXEC_OUTPUT_SYSLOG] = "syslog",
1610         [EXEC_OUTPUT_KERNEL] = "kernel",
1611         [EXEC_OUTPUT_SOCKET] = "socket"
1612 };
1613
1614 DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);
1615
1616 DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput);