src/core/execute.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2010 Lennart Poettering
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <errno.h>
  21 #include <fcntl.h>
  22 #include <glob.h>
  23 #include <grp.h>
  24 #include <poll.h>
  25 #include <signal.h>
  26 #include <string.h>
  27 #include <sys/capability.h>
  28 #include <sys/eventfd.h>
  29 #include <sys/mman.h>
  30 #include <sys/personality.h>
  31 #include <sys/prctl.h>
  32 #include <sys/shm.h>
  33 #include <sys/socket.h>
  34 #include <sys/stat.h>
  35 #include <sys/types.h>
  36 #include <sys/un.h>
  37 #include <unistd.h>
  38 #include <utmpx.h>
  39
  40 #ifdef HAVE_PAM
  41 #include <security/pam_appl.h>
  42 #endif
  43
  44 #ifdef HAVE_SELINUX
  45 #include <selinux/selinux.h>
  46 #endif
  47
  48 #ifdef HAVE_SECCOMP
  49 #include <seccomp.h>
  50 #endif
  51
  52 #ifdef HAVE_APPARMOR
  53 #include <sys/apparmor.h>
  54 #endif
  55
  56 #include "sd-messages.h"
  57
  58 #include "af-list.h"
  59 #include "alloc-util.h"
  60 #ifdef HAVE_APPARMOR
  61 #include "apparmor-util.h"
  62 #endif
  63 #include "async.h"
  64 #include "barrier.h"
  65 #include "cap-list.h"
  66 #include "capability-util.h"
  67 #include "def.h"
  68 #include "env-util.h"
  69 #include "errno-list.h"
  70 #include "execute.h"
  71 #include "exit-status.h"
  72 #include "fd-util.h"
  73 #include "fileio.h"
  74 #include "format-util.h"
  75 #include "fs-util.h"
  76 #include "glob-util.h"
  77 #include "io-util.h"
  78 #include "ioprio.h"
  79 #include "log.h"
  80 #include "macro.h"
  81 #include "missing.h"
  82 #include "mkdir.h"
  83 #include "namespace.h"
  84 #include "parse-util.h"
  85 #include "path-util.h"
  86 #include "process-util.h"
  87 #include "rlimit-util.h"
  88 #include "rm-rf.h"
  89 #ifdef HAVE_SECCOMP
  90 #include "seccomp-util.h"
  91 #endif
  92 #include "securebits.h"
  93 #include "selinux-util.h"
  94 #include "signal-util.h"
  95 #include "smack-util.h"
  96 #include "special.h"
  97 #include "string-table.h"
  98 #include "string-util.h"
  99 #include "strv.h"
 100 #include "syslog-util.h"
 101 #include "terminal-util.h"
 102 #include "unit.h"
 103 #include "user-util.h"
 104 #include "util.h"
 105 #include "utmp-wtmp.h"
 106
 107 #define IDLE_TIMEOUT_USEC (5*USEC_PER_SEC)
 108 #define IDLE_TIMEOUT2_USEC (1*USEC_PER_SEC)
 109
 110 /* This assumes there is a 'tty' group */
 111 #define TTY_MODE 0620
 112
 113 #define SNDBUF_SIZE (8*1024*1024)
 114
 115 static int shift_fds(int fds[], unsigned n_fds) {
 116         int start, restart_from;
 117
 118         if (n_fds <= 0)
 119                 return 0;
 120
 121         /* Modifies the fds array! (sorts it) */
 122
 123         assert(fds);
 124
 125         start = 0;
 126         for (;;) {
 127                 int i;
 128
 129                 restart_from = -1;
 130
 131                 for (i = start; i < (int) n_fds; i++) {
 132                         int nfd;
 133
 134                         /* Already at right index? */
 135                         if (fds[i] == i+3)
 136                                 continue;
 137
 138                         nfd = fcntl(fds[i], F_DUPFD, i + 3);
 139                         if (nfd < 0)
 140                                 return -errno;
 141
 142                         safe_close(fds[i]);
 143                         fds[i] = nfd;
 144
 145                         /* Hmm, the fd we wanted isn't free? Then
 146                          * let's remember that and try again from here */
 147                         if (nfd != i+3 && restart_from < 0)
 148                                 restart_from = i;
 149                 }
 150
 151                 if (restart_from < 0)
 152                         break;
 153
 154                 start = restart_from;
 155         }
 156
 157         return 0;
 158 }
 159
 160 static int flags_fds(const int fds[], unsigned n_fds, unsigned n_socket_fds, bool nonblock) {
 161         unsigned i;
 162         int r;
 163
 164         if (n_fds <= 0)
 165                 return 0;
 166
 167         assert(fds);
 168
 169         /* Drops/Sets O_NONBLOCK and FD_CLOEXEC from the file flags.
 170          * O_NONBLOCK only applies to socket activation though. */
 171
 172         for (i = 0; i < n_fds; i++) {
 173
 174                 if (i < n_socket_fds) {
 175                         r = fd_nonblock(fds[i], nonblock);
 176                         if (r < 0)
 177                                 return r;
 178                 }
 179
 180                 /* We unconditionally drop FD_CLOEXEC from the fds,
 181                  * since after all we want to pass these fds to our
 182                  * children */
 183
 184                 r = fd_cloexec(fds[i], false);
 185                 if (r < 0)
 186                         return r;
 187         }
 188
 189         return 0;
 190 }
 191
 192 static const char *exec_context_tty_path(const ExecContext *context) {
 193         assert(context);
 194
 195         if (context->stdio_as_fds)
 196                 return NULL;
 197
 198         if (context->tty_path)
 199                 return context->tty_path;
 200
 201         return "/dev/console";
 202 }
 203
 204 static void exec_context_tty_reset(const ExecContext *context, const ExecParameters *p) {
 205         const char *path;
 206
 207         assert(context);
 208
 209         path = exec_context_tty_path(context);
 210
 211         if (context->tty_vhangup) {
 212                 if (p && p->stdin_fd >= 0)
 213                         (void) terminal_vhangup_fd(p->stdin_fd);
 214                 else if (path)
 215                         (void) terminal_vhangup(path);
 216         }
 217
 218         if (context->tty_reset) {
 219                 if (p && p->stdin_fd >= 0)
 220                         (void) reset_terminal_fd(p->stdin_fd, true);
 221                 else if (path)
 222                         (void) reset_terminal(path);
 223         }
 224
 225         if (context->tty_vt_disallocate && path)
 226                 (void) vt_disallocate(path);
 227 }
 228
 229 static bool is_terminal_input(ExecInput i) {
 230         return IN_SET(i,
 231                       EXEC_INPUT_TTY,
 232                       EXEC_INPUT_TTY_FORCE,
 233                       EXEC_INPUT_TTY_FAIL);
 234 }
 235
 236 static bool is_terminal_output(ExecOutput o) {
 237         return IN_SET(o,
 238                       EXEC_OUTPUT_TTY,
 239                       EXEC_OUTPUT_SYSLOG_AND_CONSOLE,
 240                       EXEC_OUTPUT_KMSG_AND_CONSOLE,
 241                       EXEC_OUTPUT_JOURNAL_AND_CONSOLE);
 242 }
 243
 244 static bool exec_context_needs_term(const ExecContext *c) {
 245         assert(c);
 246
 247         /* Return true if the execution context suggests we should set $TERM to something useful. */
 248
 249         if (is_terminal_input(c->std_input))
 250                 return true;
 251
 252         if (is_terminal_output(c->std_output))
 253                 return true;
 254
 255         if (is_terminal_output(c->std_error))
 256                 return true;
 257
 258         return !!c->tty_path;
 259 }
 260
 261 static int open_null_as(int flags, int nfd) {
 262         int fd, r;
 263
 264         assert(nfd >= 0);
 265
 266         fd = open("/dev/null", flags|O_NOCTTY);
 267         if (fd < 0)
 268                 return -errno;
 269
 270         if (fd != nfd) {
 271                 r = dup2(fd, nfd) < 0 ? -errno : nfd;
 272                 safe_close(fd);
 273         } else
 274                 r = nfd;
 275
 276         return r;
 277 }
 278
 279 static int connect_journal_socket(int fd, uid_t uid, gid_t gid) {
 280         union sockaddr_union sa = {
 281                 .un.sun_family = AF_UNIX,
 282                 .un.sun_path = "/run/systemd/journal/stdout",
 283         };
 284         uid_t olduid = UID_INVALID;
 285         gid_t oldgid = GID_INVALID;
 286         int r;
 287
 288         if (gid != GID_INVALID) {
 289                 oldgid = getgid();
 290
 291                 r = setegid(gid);
 292                 if (r < 0)
 293                         return -errno;
 294         }
 295
 296         if (uid != UID_INVALID) {
 297                 olduid = getuid();
 298
 299                 r = seteuid(uid);
 300                 if (r < 0) {
 301                         r = -errno;
 302                         goto restore_gid;
 303                 }
 304         }
 305
 306         r = connect(fd, &sa.sa, SOCKADDR_UN_LEN(sa.un));
 307         if (r < 0)
 308                 r = -errno;
 309
 310         /* If we fail to restore the uid or gid, things will likely
 311            fail later on. This should only happen if an LSM interferes. */
 312
 313         if (uid != UID_INVALID)
 314                 (void) seteuid(olduid);
 315
 316  restore_gid:
 317         if (gid != GID_INVALID)
 318                 (void) setegid(oldgid);
 319
 320         return r;
 321 }
 322
 323 static int connect_logger_as(
 324                 Unit *unit,
 325                 const ExecContext *context,
 326                 ExecOutput output,
 327                 const char *ident,
 328                 int nfd,
 329                 uid_t uid,
 330                 gid_t gid) {
 331
 332         int fd, r;
 333
 334         assert(context);
 335         assert(output < _EXEC_OUTPUT_MAX);
 336         assert(ident);
 337         assert(nfd >= 0);
 338
 339         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 340         if (fd < 0)
 341                 return -errno;
 342
 343         r = connect_journal_socket(fd, uid, gid);
 344         if (r < 0)
 345                 return r;
 346
 347         if (shutdown(fd, SHUT_RD) < 0) {
 348                 safe_close(fd);
 349                 return -errno;
 350         }
 351
 352         (void) fd_inc_sndbuf(fd, SNDBUF_SIZE);
 353
 354         dprintf(fd,
 355                 "%s\n"
 356                 "%s\n"
 357                 "%i\n"
 358                 "%i\n"
 359                 "%i\n"
 360                 "%i\n"
 361                 "%i\n",
 362                 context->syslog_identifier ? context->syslog_identifier : ident,
 363                 unit->id,
 364                 context->syslog_priority,
 365                 !!context->syslog_level_prefix,
 366                 output == EXEC_OUTPUT_SYSLOG || output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE,
 367                 output == EXEC_OUTPUT_KMSG || output == EXEC_OUTPUT_KMSG_AND_CONSOLE,
 368                 is_terminal_output(output));
 369
 370         if (fd == nfd)
 371                 return nfd;
 372
 373         r = dup2(fd, nfd) < 0 ? -errno : nfd;
 374         safe_close(fd);
 375
 376         return r;
 377 }
 378 static int open_terminal_as(const char *path, mode_t mode, int nfd) {
 379         int fd, r;
 380
 381         assert(path);
 382         assert(nfd >= 0);
 383
 384         fd = open_terminal(path, mode | O_NOCTTY);
 385         if (fd < 0)
 386                 return fd;
 387
 388         if (fd != nfd) {
 389                 r = dup2(fd, nfd) < 0 ? -errno : nfd;
 390                 safe_close(fd);
 391         } else
 392                 r = nfd;
 393
 394         return r;
 395 }
 396
 397 static int fixup_input(ExecInput std_input, int socket_fd, bool apply_tty_stdin) {
 398
 399         if (is_terminal_input(std_input) && !apply_tty_stdin)
 400                 return EXEC_INPUT_NULL;
 401
 402         if (std_input == EXEC_INPUT_SOCKET && socket_fd < 0)
 403                 return EXEC_INPUT_NULL;
 404
 405         return std_input;
 406 }
 407
 408 static int fixup_output(ExecOutput std_output, int socket_fd) {
 409
 410         if (std_output == EXEC_OUTPUT_SOCKET && socket_fd < 0)
 411                 return EXEC_OUTPUT_INHERIT;
 412
 413         return std_output;
 414 }
 415
 416 static int setup_input(
 417                 const ExecContext *context,
 418                 const ExecParameters *params,
 419                 int socket_fd,
 420                 int named_iofds[3]) {
 421
 422         ExecInput i;
 423
 424         assert(context);
 425         assert(params);
 426
 427         if (params->stdin_fd >= 0) {
 428                 if (dup2(params->stdin_fd, STDIN_FILENO) < 0)
 429                         return -errno;
 430
 431                 /* Try to make this the controlling tty, if it is a tty, and reset it */
 432                 (void) ioctl(STDIN_FILENO, TIOCSCTTY, context->std_input == EXEC_INPUT_TTY_FORCE);
 433                 (void) reset_terminal_fd(STDIN_FILENO, true);
 434
 435                 return STDIN_FILENO;
 436         }
 437
 438         i = fixup_input(context->std_input, socket_fd, params->flags & EXEC_APPLY_TTY_STDIN);
 439
 440         switch (i) {
 441
 442         case EXEC_INPUT_NULL:
 443                 return open_null_as(O_RDONLY, STDIN_FILENO);
 444
 445         case EXEC_INPUT_TTY:
 446         case EXEC_INPUT_TTY_FORCE:
 447         case EXEC_INPUT_TTY_FAIL: {
 448                 int fd, r;
 449
 450                 fd = acquire_terminal(exec_context_tty_path(context),
 451                                       i == EXEC_INPUT_TTY_FAIL,
 452                                       i == EXEC_INPUT_TTY_FORCE,
 453                                       false,
 454                                       USEC_INFINITY);
 455                 if (fd < 0)
 456                         return fd;
 457
 458                 if (fd != STDIN_FILENO) {
 459                         r = dup2(fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
 460                         safe_close(fd);
 461                 } else
 462                         r = STDIN_FILENO;
 463
 464                 return r;
 465         }
 466
 467         case EXEC_INPUT_SOCKET:
 468                 return dup2(socket_fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
 469
 470         case EXEC_INPUT_NAMED_FD:
 471                 (void) fd_nonblock(named_iofds[STDIN_FILENO], false);
 472                 return dup2(named_iofds[STDIN_FILENO], STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
 473
 474         default:
 475                 assert_not_reached("Unknown input type");
 476         }
 477 }
 478
 479 static int setup_output(
 480                 Unit *unit,
 481                 const ExecContext *context,
 482                 const ExecParameters *params,
 483                 int fileno,
 484                 int socket_fd,
 485                 int named_iofds[3],
 486                 const char *ident,
 487                 uid_t uid,
 488                 gid_t gid,
 489                 dev_t *journal_stream_dev,
 490                 ino_t *journal_stream_ino) {
 491
 492         ExecOutput o;
 493         ExecInput i;
 494         int r;
 495
 496         assert(unit);
 497         assert(context);
 498         assert(params);
 499         assert(ident);
 500         assert(journal_stream_dev);
 501         assert(journal_stream_ino);
 502
 503         if (fileno == STDOUT_FILENO && params->stdout_fd >= 0) {
 504
 505                 if (dup2(params->stdout_fd, STDOUT_FILENO) < 0)
 506                         return -errno;
 507
 508                 return STDOUT_FILENO;
 509         }
 510
 511         if (fileno == STDERR_FILENO && params->stderr_fd >= 0) {
 512                 if (dup2(params->stderr_fd, STDERR_FILENO) < 0)
 513                         return -errno;
 514
 515                 return STDERR_FILENO;
 516         }
 517
 518         i = fixup_input(context->std_input, socket_fd, params->flags & EXEC_APPLY_TTY_STDIN);
 519         o = fixup_output(context->std_output, socket_fd);
 520
 521         if (fileno == STDERR_FILENO) {
 522                 ExecOutput e;
 523                 e = fixup_output(context->std_error, socket_fd);
 524
 525                 /* This expects the input and output are already set up */
 526
 527                 /* Don't change the stderr file descriptor if we inherit all
 528                  * the way and are not on a tty */
 529                 if (e == EXEC_OUTPUT_INHERIT &&
 530                     o == EXEC_OUTPUT_INHERIT &&
 531                     i == EXEC_INPUT_NULL &&
 532                     !is_terminal_input(context->std_input) &&
 533                     getppid () != 1)
 534                         return fileno;
 535
 536                 /* Duplicate from stdout if possible */
 537                 if ((e == o && e != EXEC_OUTPUT_NAMED_FD) || e == EXEC_OUTPUT_INHERIT)
 538                         return dup2(STDOUT_FILENO, fileno) < 0 ? -errno : fileno;
 539
 540                 o = e;
 541
 542         } else if (o == EXEC_OUTPUT_INHERIT) {
 543                 /* If input got downgraded, inherit the original value */
 544                 if (i == EXEC_INPUT_NULL && is_terminal_input(context->std_input))
 545                         return open_terminal_as(exec_context_tty_path(context), O_WRONLY, fileno);
 546
 547                 /* If the input is connected to anything that's not a /dev/null, inherit that... */
 548                 if (i != EXEC_INPUT_NULL)
 549                         return dup2(STDIN_FILENO, fileno) < 0 ? -errno : fileno;
 550
 551                 /* If we are not started from PID 1 we just inherit STDOUT from our parent process. */
 552                 if (getppid() != 1)
 553                         return fileno;
 554
 555                 /* We need to open /dev/null here anew, to get the right access mode. */
 556                 return open_null_as(O_WRONLY, fileno);
 557         }
 558
 559         switch (o) {
 560
 561         case EXEC_OUTPUT_NULL:
 562                 return open_null_as(O_WRONLY, fileno);
 563
 564         case EXEC_OUTPUT_TTY:
 565                 if (is_terminal_input(i))
 566                         return dup2(STDIN_FILENO, fileno) < 0 ? -errno : fileno;
 567
 568                 /* We don't reset the terminal if this is just about output */
 569                 return open_terminal_as(exec_context_tty_path(context), O_WRONLY, fileno);
 570
 571         case EXEC_OUTPUT_SYSLOG:
 572         case EXEC_OUTPUT_SYSLOG_AND_CONSOLE:
 573         case EXEC_OUTPUT_KMSG:
 574         case EXEC_OUTPUT_KMSG_AND_CONSOLE:
 575         case EXEC_OUTPUT_JOURNAL:
 576         case EXEC_OUTPUT_JOURNAL_AND_CONSOLE:
 577                 r = connect_logger_as(unit, context, o, ident, fileno, uid, gid);
 578                 if (r < 0) {
 579                         log_unit_error_errno(unit, r, "Failed to connect %s to the journal socket, ignoring: %m", fileno == STDOUT_FILENO ? "stdout" : "stderr");
 580                         r = open_null_as(O_WRONLY, fileno);
 581                 } else {
 582                         struct stat st;
 583
 584                         /* If we connected this fd to the journal via a stream, patch the device/inode into the passed
 585                          * parameters, but only then. This is useful so that we can set $JOURNAL_STREAM that permits
 586                          * services to detect whether they are connected to the journal or not. */
 587
 588                         if (fstat(fileno, &st) >= 0) {
 589                                 *journal_stream_dev = st.st_dev;
 590                                 *journal_stream_ino = st.st_ino;
 591                         }
 592                 }
 593                 return r;
 594
 595         case EXEC_OUTPUT_SOCKET:
 596                 assert(socket_fd >= 0);
 597                 return dup2(socket_fd, fileno) < 0 ? -errno : fileno;
 598
 599         case EXEC_OUTPUT_NAMED_FD:
 600                 (void) fd_nonblock(named_iofds[fileno], false);
 601                 return dup2(named_iofds[fileno], fileno) < 0 ? -errno : fileno;
 602
 603         default:
 604                 assert_not_reached("Unknown error type");
 605         }
 606 }
 607
 608 static int chown_terminal(int fd, uid_t uid) {
 609         struct stat st;
 610
 611         assert(fd >= 0);
 612
 613         /* Before we chown/chmod the TTY, let's ensure this is actually a tty */
 614         if (isatty(fd) < 1)
 615                 return 0;
 616
 617         /* This might fail. What matters are the results. */
 618         (void) fchown(fd, uid, -1);
 619         (void) fchmod(fd, TTY_MODE);
 620
 621         if (fstat(fd, &st) < 0)
 622                 return -errno;
 623
 624         if (st.st_uid != uid || (st.st_mode & 0777) != TTY_MODE)
 625                 return -EPERM;
 626
 627         return 0;
 628 }
 629
 630 static int setup_confirm_stdio(const char *vc, int *_saved_stdin, int *_saved_stdout) {
 631         _cleanup_close_ int fd = -1, saved_stdin = -1, saved_stdout = -1;
 632         int r;
 633
 634         assert(_saved_stdin);
 635         assert(_saved_stdout);
 636
 637         saved_stdin = fcntl(STDIN_FILENO, F_DUPFD, 3);
 638         if (saved_stdin < 0)
 639                 return -errno;
 640
 641         saved_stdout = fcntl(STDOUT_FILENO, F_DUPFD, 3);
 642         if (saved_stdout < 0)
 643                 return -errno;
 644
 645         fd = acquire_terminal(vc, false, false, false, DEFAULT_CONFIRM_USEC);
 646         if (fd < 0)
 647                 return fd;
 648
 649         r = chown_terminal(fd, getuid());
 650         if (r < 0)
 651                 return r;
 652
 653         r = reset_terminal_fd(fd, true);
 654         if (r < 0)
 655                 return r;
 656
 657         if (dup2(fd, STDIN_FILENO) < 0)
 658                 return -errno;
 659
 660         if (dup2(fd, STDOUT_FILENO) < 0)
 661                 return -errno;
 662
 663         if (fd >= 2)
 664                 safe_close(fd);
 665         fd = -1;
 666
 667         *_saved_stdin = saved_stdin;
 668         *_saved_stdout = saved_stdout;
 669
 670         saved_stdin = saved_stdout = -1;
 671
 672         return 0;
 673 }
 674
 675 static void write_confirm_error_fd(int err, int fd, const Unit *u) {
 676         assert(err < 0);
 677
 678         if (err == -ETIMEDOUT)
 679                 dprintf(fd, "Confirmation question timed out for %s, assuming positive response.\n", u->id);
 680         else {
 681                 errno = -err;
 682                 dprintf(fd, "Couldn't ask confirmation for %s: %m, assuming positive response.\n", u->id);
 683         }
 684 }
 685
 686 static void write_confirm_error(int err, const char *vc, const Unit *u) {
 687         _cleanup_close_ int fd = -1;
 688
 689         assert(vc);
 690
 691         fd = open_terminal(vc, O_WRONLY|O_NOCTTY|O_CLOEXEC);
 692         if (fd < 0)
 693                 return;
 694
 695         write_confirm_error_fd(err, fd, u);
 696 }
 697
 698 static int restore_confirm_stdio(int *saved_stdin, int *saved_stdout) {
 699         int r = 0;
 700
 701         assert(saved_stdin);
 702         assert(saved_stdout);
 703
 704         release_terminal();
 705
 706         if (*saved_stdin >= 0)
 707                 if (dup2(*saved_stdin, STDIN_FILENO) < 0)
 708                         r = -errno;
 709
 710         if (*saved_stdout >= 0)
 711                 if (dup2(*saved_stdout, STDOUT_FILENO) < 0)
 712                         r = -errno;
 713
 714         *saved_stdin = safe_close(*saved_stdin);
 715         *saved_stdout = safe_close(*saved_stdout);
 716
 717         return r;
 718 }
 719
 720 enum {
 721         CONFIRM_PRETEND_FAILURE = -1,
 722         CONFIRM_PRETEND_SUCCESS =  0,
 723         CONFIRM_EXECUTE = 1,
 724 };
 725
 726 static int ask_for_confirmation(const char *vc, Unit *u, const char *cmdline) {
 727         int saved_stdout = -1, saved_stdin = -1, r;
 728         _cleanup_free_ char *e = NULL;
 729         char c;
 730
 731         /* For any internal errors, assume a positive response. */
 732         r = setup_confirm_stdio(vc, &saved_stdin, &saved_stdout);
 733         if (r < 0) {
 734                 write_confirm_error(r, vc, u);
 735                 return CONFIRM_EXECUTE;
 736         }
 737
 738         /* confirm_spawn might have been disabled while we were sleeping. */
 739         if (manager_is_confirm_spawn_disabled(u->manager)) {
 740                 r = 1;
 741                 goto restore_stdio;
 742         }
 743
 744         e = ellipsize(cmdline, 60, 100);
 745         if (!e) {
 746                 log_oom();
 747                 r = CONFIRM_EXECUTE;
 748                 goto restore_stdio;
 749         }
 750
 751         for (;;) {
 752                 r = ask_char(&c, "yfshiDjcn", "Execute %s? [y, f, s – h for help] ", e);
 753                 if (r < 0) {
 754                         write_confirm_error_fd(r, STDOUT_FILENO, u);
 755                         r = CONFIRM_EXECUTE;
 756                         goto restore_stdio;
 757                 }
 758
 759                 switch (c) {
 760                 case 'c':
 761                         printf("Resuming normal execution.\n");
 762                         manager_disable_confirm_spawn();
 763                         r = 1;
 764                         break;
 765                 case 'D':
 766                         unit_dump(u, stdout, "  ");
 767                         continue; /* ask again */
 768                 case 'f':
 769                         printf("Failing execution.\n");
 770                         r = CONFIRM_PRETEND_FAILURE;
 771                         break;
 772                 case 'h':
 773                         printf("  c - continue, proceed without asking anymore\n"
 774                                "  D - dump, show the state of the unit\n"
 775                                "  f - fail, don't execute the command and pretend it failed\n"
 776                                "  h - help\n"
 777                                "  i - info, show a short summary of the unit\n"
 778                                "  j - jobs, show jobs that are in progress\n"
 779                                "  s - skip, don't execute the command and pretend it succeeded\n"
 780                                "  y - yes, execute the command\n");
 781                         continue; /* ask again */
 782                 case 'i':
 783                         printf("  Description: %s\n"
 784                                "  Unit:        %s\n"
 785                                "  Command:     %s\n",
 786                                u->id, u->description, cmdline);
 787                         continue; /* ask again */
 788                 case 'j':
 789                         manager_dump_jobs(u->manager, stdout, "  ");
 790                         continue; /* ask again */
 791                 case 'n':
 792                         /* 'n' was removed in favor of 'f'. */
 793                         printf("Didn't understand 'n', did you mean 'f'?\n");
 794                         continue; /* ask again */
 795                 case 's':
 796                         printf("Skipping execution.\n");
 797                         r = CONFIRM_PRETEND_SUCCESS;
 798                         break;
 799                 case 'y':
 800                         r = CONFIRM_EXECUTE;
 801                         break;
 802                 default:
 803                         assert_not_reached("Unhandled choice");
 804                 }
 805                 break;
 806         }
 807
 808 restore_stdio:
 809         restore_confirm_stdio(&saved_stdin, &saved_stdout);
 810         return r;
 811 }
 812
 813 static int get_fixed_user(const ExecContext *c, const char **user,
 814                           uid_t *uid, gid_t *gid,
 815                           const char **home, const char **shell) {
 816         int r;
 817         const char *name;
 818
 819         assert(c);
 820
 821         if (!c->user)
 822                 return 0;
 823
 824         /* Note that we don't set $HOME or $SHELL if they are not particularly enlightening anyway
 825          * (i.e. are "/" or "/bin/nologin"). */
 826
 827         name = c->user;
 828         r = get_user_creds_clean(&name, uid, gid, home, shell);
 829         if (r < 0)
 830                 return r;
 831
 832         *user = name;
 833         return 0;
 834 }
 835
 836 static int get_fixed_group(const ExecContext *c, const char **group, gid_t *gid) {
 837         int r;
 838         const char *name;
 839
 840         assert(c);
 841
 842         if (!c->group)
 843                 return 0;
 844
 845         name = c->group;
 846         r = get_group_creds(&name, gid);
 847         if (r < 0)
 848                 return r;
 849
 850         *group = name;
 851         return 0;
 852 }
 853
 854 static int get_supplementary_groups(const ExecContext *c, const char *user,
 855                                     const char *group, gid_t gid,
 856                                     gid_t **supplementary_gids, int *ngids) {
 857         char **i;
 858         int r, k = 0;
 859         int ngroups_max;
 860         bool keep_groups = false;
 861         gid_t *groups = NULL;
 862         _cleanup_free_ gid_t *l_gids = NULL;
 863
 864         assert(c);
 865
 866         /*
 867          * If user is given, then lookup GID and supplementary groups list.
 868          * We avoid NSS lookups for gid=0. Also we have to initialize groups
 869          * here and as early as possible so we keep the list of supplementary
 870          * groups of the caller.
 871          */
 872         if (user && gid_is_valid(gid) && gid != 0) {
 873                 /* First step, initialize groups from /etc/groups */
 874                 if (initgroups(user, gid) < 0)
 875                         return -errno;
 876
 877                 keep_groups = true;
 878         }
 879
 880         if (!c->supplementary_groups)
 881                 return 0;
 882
 883         /*
 884          * If SupplementaryGroups= was passed then NGROUPS_MAX has to
 885          * be positive, otherwise fail.
 886          */
 887         errno = 0;
 888         ngroups_max = (int) sysconf(_SC_NGROUPS_MAX);
 889         if (ngroups_max <= 0) {
 890                 if (errno > 0)
 891                         return -errno;
 892                 else
 893                         return -EOPNOTSUPP; /* For all other values */
 894         }
 895
 896         l_gids = new(gid_t, ngroups_max);
 897         if (!l_gids)
 898                 return -ENOMEM;
 899
 900         if (keep_groups) {
 901                 /*
 902                  * Lookup the list of groups that the user belongs to, we
 903                  * avoid NSS lookups here too for gid=0.
 904                  */
 905                 k = ngroups_max;
 906                 if (getgrouplist(user, gid, l_gids, &k) < 0)
 907                         return -EINVAL;
 908         } else
 909                 k = 0;
 910
 911         STRV_FOREACH(i, c->supplementary_groups) {
 912                 const char *g;
 913
 914                 if (k >= ngroups_max)
 915                         return -E2BIG;
 916
 917                 g = *i;
 918                 r = get_group_creds(&g, l_gids+k);
 919                 if (r < 0)
 920                         return r;
 921
 922                 k++;
 923         }
 924
 925         /*
 926          * Sets ngids to zero to drop all supplementary groups, happens
 927          * when we are under root and SupplementaryGroups= is empty.
 928          */
 929         if (k == 0) {
 930                 *ngids = 0;
 931                 return 0;
 932         }
 933
 934         /* Otherwise get the final list of supplementary groups */
 935         groups = memdup(l_gids, sizeof(gid_t) * k);
 936         if (!groups)
 937                 return -ENOMEM;
 938
 939         *supplementary_gids = groups;
 940         *ngids = k;
 941
 942         groups = NULL;
 943
 944         return 0;
 945 }
 946
 947 static int enforce_groups(const ExecContext *context, gid_t gid,
 948                           gid_t *supplementary_gids, int ngids) {
 949         int r;
 950
 951         assert(context);
 952
 953         /* Handle SupplementaryGroups= even if it is empty */
 954         if (context->supplementary_groups) {
 955                 r = maybe_setgroups(ngids, supplementary_gids);
 956                 if (r < 0)
 957                         return r;
 958         }
 959
 960         if (gid_is_valid(gid)) {
 961                 /* Then set our gids */
 962                 if (setresgid(gid, gid, gid) < 0)
 963                         return -errno;
 964         }
 965
 966         return 0;
 967 }
 968
 969 static int enforce_user(const ExecContext *context, uid_t uid) {
 970         assert(context);
 971
 972         if (!uid_is_valid(uid))
 973                 return 0;
 974
 975         /* Sets (but doesn't look up) the uid and make sure we keep the
 976          * capabilities while doing so. */
 977
 978         if (context->capability_ambient_set != 0) {
 979
 980                 /* First step: If we need to keep capabilities but
 981                  * drop privileges we need to make sure we keep our
 982                  * caps, while we drop privileges. */
 983                 if (uid != 0) {
 984                         int sb = context->secure_bits | 1<<SECURE_KEEP_CAPS;
 985
 986                         if (prctl(PR_GET_SECUREBITS) != sb)
 987                                 if (prctl(PR_SET_SECUREBITS, sb) < 0)
 988                                         return -errno;
 989                 }
 990         }
 991
 992         /* Second step: actually set the uids */
 993         if (setresuid(uid, uid, uid) < 0)
 994                 return -errno;
 995
 996         /* At this point we should have all necessary capabilities but
 997            are otherwise a normal user. However, the caps might got
 998            corrupted due to the setresuid() so we need clean them up
 999            later. This is done outside of this call. */
1000
1001         return 0;
1002 }
1003
1004 #ifdef HAVE_PAM
1005
1006 static int null_conv(
1007                 int num_msg,
1008                 const struct pam_message **msg,
1009                 struct pam_response **resp,
1010                 void *appdata_ptr) {
1011
1012         /* We don't support conversations */
1013
1014         return PAM_CONV_ERR;
1015 }
1016
1017 #endif
1018
1019 static int setup_pam(
1020                 const char *name,
1021                 const char *user,
1022                 uid_t uid,
1023                 gid_t gid,
1024                 const char *tty,
1025                 char ***env,
1026                 int fds[], unsigned n_fds) {
1027
1028 #ifdef HAVE_PAM
1029
1030         static const struct pam_conv conv = {
1031                 .conv = null_conv,
1032                 .appdata_ptr = NULL
1033         };
1034
1035         _cleanup_(barrier_destroy) Barrier barrier = BARRIER_NULL;
1036         pam_handle_t *handle = NULL;
1037         sigset_t old_ss;
1038         int pam_code = PAM_SUCCESS, r;
1039         char **nv, **e = NULL;
1040         bool close_session = false;
1041         pid_t pam_pid = 0, parent_pid;
1042         int flags = 0;
1043
1044         assert(name);
1045         assert(user);
1046         assert(env);
1047
1048         /* We set up PAM in the parent process, then fork. The child
1049          * will then stay around until killed via PR_GET_PDEATHSIG or
1050          * systemd via the cgroup logic. It will then remove the PAM
1051          * session again. The parent process will exec() the actual
1052          * daemon. We do things this way to ensure that the main PID
1053          * of the daemon is the one we initially fork()ed. */
1054
1055         r = barrier_create(&barrier);
1056         if (r < 0)
1057                 goto fail;
1058
1059         if (log_get_max_level() < LOG_DEBUG)
1060                 flags |= PAM_SILENT;
1061
1062         pam_code = pam_start(name, user, &conv, &handle);
1063         if (pam_code != PAM_SUCCESS) {
1064                 handle = NULL;
1065                 goto fail;
1066         }
1067
1068         if (tty) {
1069                 pam_code = pam_set_item(handle, PAM_TTY, tty);
1070                 if (pam_code != PAM_SUCCESS)
1071                         goto fail;
1072         }
1073
1074         STRV_FOREACH(nv, *env) {
1075                 pam_code = pam_putenv(handle, *nv);
1076                 if (pam_code != PAM_SUCCESS)
1077                         goto fail;
1078         }
1079
1080         pam_code = pam_acct_mgmt(handle, flags);
1081         if (pam_code != PAM_SUCCESS)
1082                 goto fail;
1083
1084         pam_code = pam_open_session(handle, flags);
1085         if (pam_code != PAM_SUCCESS)
1086                 goto fail;
1087
1088         close_session = true;
1089
1090         e = pam_getenvlist(handle);
1091         if (!e) {
1092                 pam_code = PAM_BUF_ERR;
1093                 goto fail;
1094         }
1095
1096         /* Block SIGTERM, so that we know that it won't get lost in
1097          * the child */
1098
1099         assert_se(sigprocmask_many(SIG_BLOCK, &old_ss, SIGTERM, -1) >= 0);
1100
1101         parent_pid = getpid();
1102
1103         pam_pid = fork();
1104         if (pam_pid < 0) {
1105                 r = -errno;
1106                 goto fail;
1107         }
1108
1109         if (pam_pid == 0) {
1110                 int sig, ret = EXIT_PAM;
1111
1112                 /* The child's job is to reset the PAM session on
1113                  * termination */
1114                 barrier_set_role(&barrier, BARRIER_CHILD);
1115
1116                 /* This string must fit in 10 chars (i.e. the length
1117                  * of "/sbin/init"), to look pretty in /bin/ps */
1118                 rename_process("(sd-pam)");
1119
1120                 /* Make sure we don't keep open the passed fds in this
1121                 child. We assume that otherwise only those fds are
1122                 open here that have been opened by PAM. */
1123                 close_many(fds, n_fds);
1124
1125                 /* Drop privileges - we don't need any to pam_close_session
1126                  * and this will make PR_SET_PDEATHSIG work in most cases.
1127                  * If this fails, ignore the error - but expect sd-pam threads
1128                  * to fail to exit normally */
1129
1130                 r = maybe_setgroups(0, NULL);
1131                 if (r < 0)
1132                         log_warning_errno(r, "Failed to setgroups() in sd-pam: %m");
1133                 if (setresgid(gid, gid, gid) < 0)
1134                         log_warning_errno(errno, "Failed to setresgid() in sd-pam: %m");
1135                 if (setresuid(uid, uid, uid) < 0)
1136                         log_warning_errno(errno, "Failed to setresuid() in sd-pam: %m");
1137
1138                 (void) ignore_signals(SIGPIPE, -1);
1139
1140                 /* Wait until our parent died. This will only work if
1141                  * the above setresuid() succeeds, otherwise the kernel
1142                  * will not allow unprivileged parents kill their privileged
1143                  * children this way. We rely on the control groups kill logic
1144                  * to do the rest for us. */
1145                 if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
1146                         goto child_finish;
1147
1148                 /* Tell the parent that our setup is done. This is especially
1149                  * important regarding dropping privileges. Otherwise, unit
1150                  * setup might race against our setresuid(2) call.
1151                  *
1152                  * If the parent aborted, we'll detect this below, hence ignore
1153                  * return failure here. */
1154                 (void) barrier_place(&barrier);
1155
1156                 /* Check if our parent process might already have died? */
1157                 if (getppid() == parent_pid) {
1158                         sigset_t ss;
1159
1160                         assert_se(sigemptyset(&ss) >= 0);
1161                         assert_se(sigaddset(&ss, SIGTERM) >= 0);
1162
1163                         for (;;) {
1164                                 if (sigwait(&ss, &sig) < 0) {
1165                                         if (errno == EINTR)
1166                                                 continue;
1167
1168                                         goto child_finish;
1169                                 }
1170
1171                                 assert(sig == SIGTERM);
1172                                 break;
1173                         }
1174                 }
1175
1176                 /* If our parent died we'll end the session */
1177                 if (getppid() != parent_pid) {
1178                         pam_code = pam_close_session(handle, flags);
1179                         if (pam_code != PAM_SUCCESS)
1180                                 goto child_finish;
1181                 }
1182
1183                 ret = 0;
1184
1185         child_finish:
1186                 pam_end(handle, pam_code | flags);
1187                 _exit(ret);
1188         }
1189
1190         barrier_set_role(&barrier, BARRIER_PARENT);
1191
1192         /* If the child was forked off successfully it will do all the
1193          * cleanups, so forget about the handle here. */
1194         handle = NULL;
1195
1196         /* Unblock SIGTERM again in the parent */
1197         assert_se(sigprocmask(SIG_SETMASK, &old_ss, NULL) >= 0);
1198
1199         /* We close the log explicitly here, since the PAM modules
1200          * might have opened it, but we don't want this fd around. */
1201         closelog();
1202
1203         /* Synchronously wait for the child to initialize. We don't care for
1204          * errors as we cannot recover. However, warn loudly if it happens. */
1205         if (!barrier_place_and_sync(&barrier))
1206                 log_error("PAM initialization failed");
1207
1208         strv_free(*env);
1209         *env = e;
1210
1211         return 0;
1212
1213 fail:
1214         if (pam_code != PAM_SUCCESS) {
1215                 log_error("PAM failed: %s", pam_strerror(handle, pam_code));
1216                 r = -EPERM;  /* PAM errors do not map to errno */
1217         } else
1218                 log_error_errno(r, "PAM failed: %m");
1219
1220         if (handle) {
1221                 if (close_session)
1222                         pam_code = pam_close_session(handle, flags);
1223
1224                 pam_end(handle, pam_code | flags);
1225         }
1226
1227         strv_free(e);
1228         closelog();
1229
1230         return r;
1231 #else
1232         return 0;
1233 #endif
1234 }
1235
1236 static void rename_process_from_path(const char *path) {
1237         char process_name[11];
1238         const char *p;
1239         size_t l;
1240
1241         /* This resulting string must fit in 10 chars (i.e. the length
1242          * of "/sbin/init") to look pretty in /bin/ps */
1243
1244         p = basename(path);
1245         if (isempty(p)) {
1246                 rename_process("(...)");
1247                 return;
1248         }
1249
1250         l = strlen(p);
1251         if (l > 8) {
1252                 /* The end of the process name is usually more
1253                  * interesting, since the first bit might just be
1254                  * "systemd-" */
1255                 p = p + l - 8;
1256                 l = 8;
1257         }
1258
1259         process_name[0] = '(';
1260         memcpy(process_name+1, p, l);
1261         process_name[1+l] = ')';
1262         process_name[1+l+1] = 0;
1263
1264         rename_process(process_name);
1265 }
1266
1267 static bool context_has_address_families(const ExecContext *c) {
1268         assert(c);
1269
1270         return c->address_families_whitelist ||
1271                 !set_isempty(c->address_families);
1272 }
1273
1274 static bool context_has_syscall_filters(const ExecContext *c) {
1275         assert(c);
1276
1277         return c->syscall_whitelist ||
1278                 !set_isempty(c->syscall_filter);
1279 }
1280
1281 static bool context_has_no_new_privileges(const ExecContext *c) {
1282         assert(c);
1283
1284         if (c->no_new_privileges)
1285                 return true;
1286
1287         if (have_effective_cap(CAP_SYS_ADMIN)) /* if we are privileged, we don't need NNP */
1288                 return false;
1289
1290         /* We need NNP if we have any form of seccomp and are unprivileged */
1291         return context_has_address_families(c) ||
1292                 c->memory_deny_write_execute ||
1293                 c->restrict_realtime ||
1294                 exec_context_restrict_namespaces_set(c) ||
1295                 c->protect_kernel_tunables ||
1296                 c->protect_kernel_modules ||
1297                 c->private_devices ||
1298                 context_has_syscall_filters(c) ||
1299                 !set_isempty(c->syscall_archs);
1300 }
1301
1302 #ifdef HAVE_SECCOMP
1303
1304 static bool skip_seccomp_unavailable(const Unit* u, const char* msg) {
1305
1306         if (is_seccomp_available())
1307                 return false;
1308
1309         log_open();
1310         log_unit_debug(u, "SECCOMP features not detected in the kernel, skipping %s", msg);
1311         log_close();
1312         return true;
1313 }
1314
1315 static int apply_syscall_filter(const Unit* u, const ExecContext *c) {
1316         uint32_t negative_action, default_action, action;
1317
1318         assert(u);
1319         assert(c);
1320
1321         if (!context_has_syscall_filters(c))
1322                 return 0;
1323
1324         if (skip_seccomp_unavailable(u, "SystemCallFilter="))
1325                 return 0;
1326
1327         negative_action = c->syscall_errno == 0 ? SCMP_ACT_KILL : SCMP_ACT_ERRNO(c->syscall_errno);
1328
1329         if (c->syscall_whitelist) {
1330                 default_action = negative_action;
1331                 action = SCMP_ACT_ALLOW;
1332         } else {
1333                 default_action = SCMP_ACT_ALLOW;
1334                 action = negative_action;
1335         }
1336
1337         return seccomp_load_syscall_filter_set_raw(default_action, c->syscall_filter, action);
1338 }
1339
1340 static int apply_syscall_archs(const Unit *u, const ExecContext *c) {
1341         assert(u);
1342         assert(c);
1343
1344         if (set_isempty(c->syscall_archs))
1345                 return 0;
1346
1347         if (skip_seccomp_unavailable(u, "SystemCallArchitectures="))
1348                 return 0;
1349
1350         return seccomp_restrict_archs(c->syscall_archs);
1351 }
1352
1353 static int apply_address_families(const Unit* u, const ExecContext *c) {
1354         assert(u);
1355         assert(c);
1356
1357         if (!context_has_address_families(c))
1358                 return 0;
1359
1360         if (skip_seccomp_unavailable(u, "RestrictAddressFamilies="))
1361                 return 0;
1362
1363         return seccomp_restrict_address_families(c->address_families, c->address_families_whitelist);
1364 }
1365
1366 static int apply_memory_deny_write_execute(const Unit* u, const ExecContext *c) {
1367         assert(u);
1368         assert(c);
1369
1370         if (!c->memory_deny_write_execute)
1371                 return 0;
1372
1373         if (skip_seccomp_unavailable(u, "MemoryDenyWriteExecute="))
1374                 return 0;
1375
1376         return seccomp_memory_deny_write_execute();
1377 }
1378
1379 static int apply_restrict_realtime(const Unit* u, const ExecContext *c) {
1380         assert(u);
1381         assert(c);
1382
1383         if (!c->restrict_realtime)
1384                 return 0;
1385
1386         if (skip_seccomp_unavailable(u, "RestrictRealtime="))
1387                 return 0;
1388
1389         return seccomp_restrict_realtime();
1390 }
1391
1392 static int apply_protect_sysctl(const Unit *u, const ExecContext *c) {
1393         assert(u);
1394         assert(c);
1395
1396         /* Turn off the legacy sysctl() system call. Many distributions turn this off while building the kernel, but
1397          * let's protect even those systems where this is left on in the kernel. */
1398
1399         if (!c->protect_kernel_tunables)
1400                 return 0;
1401
1402         if (skip_seccomp_unavailable(u, "ProtectKernelTunables="))
1403                 return 0;
1404
1405         return seccomp_protect_sysctl();
1406 }
1407
1408 static int apply_protect_kernel_modules(const Unit *u, const ExecContext *c) {
1409         assert(u);
1410         assert(c);
1411
1412         /* Turn off module syscalls on ProtectKernelModules=yes */
1413
1414         if (!c->protect_kernel_modules)
1415                 return 0;
1416
1417         if (skip_seccomp_unavailable(u, "ProtectKernelModules="))
1418                 return 0;
1419
1420         return seccomp_load_syscall_filter_set(SCMP_ACT_ALLOW, syscall_filter_sets + SYSCALL_FILTER_SET_MODULE, SCMP_ACT_ERRNO(EPERM));
1421 }
1422
1423 static int apply_private_devices(const Unit *u, const ExecContext *c) {
1424         assert(u);
1425         assert(c);
1426
1427         /* If PrivateDevices= is set, also turn off iopl and all @raw-io syscalls. */
1428
1429         if (!c->private_devices)
1430                 return 0;
1431
1432         if (skip_seccomp_unavailable(u, "PrivateDevices="))
1433                 return 0;
1434
1435         return seccomp_load_syscall_filter_set(SCMP_ACT_ALLOW, syscall_filter_sets + SYSCALL_FILTER_SET_RAW_IO, SCMP_ACT_ERRNO(EPERM));
1436 }
1437
1438 static int apply_restrict_namespaces(Unit *u, const ExecContext *c) {
1439         assert(u);
1440         assert(c);
1441
1442         if (!exec_context_restrict_namespaces_set(c))
1443                 return 0;
1444
1445         if (skip_seccomp_unavailable(u, "RestrictNamespaces="))
1446                 return 0;
1447
1448         return seccomp_restrict_namespaces(c->restrict_namespaces);
1449 }
1450
1451 #endif
1452
1453 static void do_idle_pipe_dance(int idle_pipe[4]) {
1454         assert(idle_pipe);
1455
1456         idle_pipe[1] = safe_close(idle_pipe[1]);
1457         idle_pipe[2] = safe_close(idle_pipe[2]);
1458
1459         if (idle_pipe[0] >= 0) {
1460                 int r;
1461
1462                 r = fd_wait_for_event(idle_pipe[0], POLLHUP, IDLE_TIMEOUT_USEC);
1463
1464                 if (idle_pipe[3] >= 0 && r == 0 /* timeout */) {
1465                         ssize_t n;
1466
1467                         /* Signal systemd that we are bored and want to continue. */
1468                         n = write(idle_pipe[3], "x", 1);
1469                         if (n > 0)
1470                                 /* Wait for systemd to react to the signal above. */
1471                                 fd_wait_for_event(idle_pipe[0], POLLHUP, IDLE_TIMEOUT2_USEC);
1472                 }
1473
1474                 idle_pipe[0] = safe_close(idle_pipe[0]);
1475
1476         }
1477
1478         idle_pipe[3] = safe_close(idle_pipe[3]);
1479 }
1480
1481 static int build_environment(
1482                 Unit *u,
1483                 const ExecContext *c,
1484                 const ExecParameters *p,
1485                 unsigned n_fds,
1486                 const char *home,
1487                 const char *username,
1488                 const char *shell,
1489                 dev_t journal_stream_dev,
1490                 ino_t journal_stream_ino,
1491                 char ***ret) {
1492
1493         _cleanup_strv_free_ char **our_env = NULL;
1494         unsigned n_env = 0;
1495         char *x;
1496
1497         assert(u);
1498         assert(c);
1499         assert(ret);
1500
1501         our_env = new0(char*, 14);
1502         if (!our_env)
1503                 return -ENOMEM;
1504
1505         if (n_fds > 0) {
1506                 _cleanup_free_ char *joined = NULL;
1507
1508                 if (asprintf(&x, "LISTEN_PID="PID_FMT, getpid()) < 0)
1509                         return -ENOMEM;
1510                 our_env[n_env++] = x;
1511
1512                 if (asprintf(&x, "LISTEN_FDS=%u", n_fds) < 0)
1513                         return -ENOMEM;
1514                 our_env[n_env++] = x;
1515
1516                 joined = strv_join(p->fd_names, ":");
1517                 if (!joined)
1518                         return -ENOMEM;
1519
1520                 x = strjoin("LISTEN_FDNAMES=", joined);
1521                 if (!x)
1522                         return -ENOMEM;
1523                 our_env[n_env++] = x;
1524         }
1525
1526         if ((p->flags & EXEC_SET_WATCHDOG) && p->watchdog_usec > 0) {
1527                 if (asprintf(&x, "WATCHDOG_PID="PID_FMT, getpid()) < 0)
1528                         return -ENOMEM;
1529                 our_env[n_env++] = x;
1530
1531                 if (asprintf(&x, "WATCHDOG_USEC="USEC_FMT, p->watchdog_usec) < 0)
1532                         return -ENOMEM;
1533                 our_env[n_env++] = x;
1534         }
1535
1536         /* If this is D-Bus, tell the nss-systemd module, since it relies on being able to use D-Bus look up dynamic
1537          * users via PID 1, possibly dead-locking the dbus daemon. This way it will not use D-Bus to resolve names, but
1538          * check the database directly. */
1539         if (unit_has_name(u, SPECIAL_DBUS_SERVICE)) {
1540                 x = strdup("SYSTEMD_NSS_BYPASS_BUS=1");
1541                 if (!x)
1542                         return -ENOMEM;
1543                 our_env[n_env++] = x;
1544         }
1545
1546         if (home) {
1547                 x = strappend("HOME=", home);
1548                 if (!x)
1549                         return -ENOMEM;
1550                 our_env[n_env++] = x;
1551         }
1552
1553         if (username) {
1554                 x = strappend("LOGNAME=", username);
1555                 if (!x)
1556                         return -ENOMEM;
1557                 our_env[n_env++] = x;
1558
1559                 x = strappend("USER=", username);
1560                 if (!x)
1561                         return -ENOMEM;
1562                 our_env[n_env++] = x;
1563         }
1564
1565         if (shell) {
1566                 x = strappend("SHELL=", shell);
1567                 if (!x)
1568                         return -ENOMEM;
1569                 our_env[n_env++] = x;
1570         }
1571
1572         if (!sd_id128_is_null(u->invocation_id)) {
1573                 if (asprintf(&x, "INVOCATION_ID=" SD_ID128_FORMAT_STR, SD_ID128_FORMAT_VAL(u->invocation_id)) < 0)
1574                         return -ENOMEM;
1575
1576                 our_env[n_env++] = x;
1577         }
1578
1579         if (exec_context_needs_term(c)) {
1580                 const char *tty_path, *term = NULL;
1581
1582                 tty_path = exec_context_tty_path(c);
1583
1584                 /* If we are forked off PID 1 and we are supposed to operate on /dev/console, then let's try to inherit
1585                  * the $TERM set for PID 1. This is useful for containers so that the $TERM the container manager
1586                  * passes to PID 1 ends up all the way in the console login shown. */
1587
1588                 if (path_equal(tty_path, "/dev/console") && getppid() == 1)
1589                         term = getenv("TERM");
1590                 if (!term)
1591                         term = default_term_for_tty(tty_path);
1592
1593                 x = strappend("TERM=", term);
1594                 if (!x)
1595                         return -ENOMEM;
1596                 our_env[n_env++] = x;
1597         }
1598
1599         if (journal_stream_dev != 0 && journal_stream_ino != 0) {
1600                 if (asprintf(&x, "JOURNAL_STREAM=" DEV_FMT ":" INO_FMT, journal_stream_dev, journal_stream_ino) < 0)
1601                         return -ENOMEM;
1602
1603                 our_env[n_env++] = x;
1604         }
1605
1606         our_env[n_env++] = NULL;
1607         assert(n_env <= 12);
1608
1609         *ret = our_env;
1610         our_env = NULL;
1611
1612         return 0;
1613 }
1614
1615 static int build_pass_environment(const ExecContext *c, char ***ret) {
1616         _cleanup_strv_free_ char **pass_env = NULL;
1617         size_t n_env = 0, n_bufsize = 0;
1618         char **i;
1619
1620         STRV_FOREACH(i, c->pass_environment) {
1621                 _cleanup_free_ char *x = NULL;
1622                 char *v;
1623
1624                 v = getenv(*i);
1625                 if (!v)
1626                         continue;
1627                 x = strjoin(*i, "=", v);
1628                 if (!x)
1629                         return -ENOMEM;
1630                 if (!GREEDY_REALLOC(pass_env, n_bufsize, n_env + 2))
1631                         return -ENOMEM;
1632                 pass_env[n_env++] = x;
1633                 pass_env[n_env] = NULL;
1634                 x = NULL;
1635         }
1636
1637         *ret = pass_env;
1638         pass_env = NULL;
1639
1640         return 0;
1641 }
1642
1643 static bool exec_needs_mount_namespace(
1644                 const ExecContext *context,
1645                 const ExecParameters *params,
1646                 ExecRuntime *runtime) {
1647
1648         assert(context);
1649         assert(params);
1650
1651         if (context->root_image)
1652                 return true;
1653
1654         if (!strv_isempty(context->read_write_paths) ||
1655             !strv_isempty(context->read_only_paths) ||
1656             !strv_isempty(context->inaccessible_paths))
1657                 return true;
1658
1659         if (context->n_bind_mounts > 0)
1660                 return true;
1661
1662         if (context->mount_flags != 0)
1663                 return true;
1664
1665         if (context->private_tmp && runtime && (runtime->tmp_dir || runtime->var_tmp_dir))
1666                 return true;
1667
1668         if (context->private_devices ||
1669             context->protect_system != PROTECT_SYSTEM_NO ||
1670             context->protect_home != PROTECT_HOME_NO ||
1671             context->protect_kernel_tunables ||
1672             context->protect_kernel_modules ||
1673             context->protect_control_groups)
1674                 return true;
1675
1676         if (context->mount_apivfs && (context->root_image || context->root_directory))
1677                 return true;
1678
1679         return false;
1680 }
1681
1682 static int setup_private_users(uid_t uid, gid_t gid) {
1683         _cleanup_free_ char *uid_map = NULL, *gid_map = NULL;
1684         _cleanup_close_pair_ int errno_pipe[2] = { -1, -1 };
1685         _cleanup_close_ int unshare_ready_fd = -1;
1686         _cleanup_(sigkill_waitp) pid_t pid = 0;
1687         uint64_t c = 1;
1688         siginfo_t si;
1689         ssize_t n;
1690         int r;
1691
1692         /* Set up a user namespace and map root to root, the selected UID/GID to itself, and everything else to
1693          * nobody. In order to be able to write this mapping we need CAP_SETUID in the original user namespace, which
1694          * we however lack after opening the user namespace. To work around this we fork() a temporary child process,
1695          * which waits for the parent to create the new user namespace while staying in the original namespace. The
1696          * child then writes the UID mapping, under full privileges. The parent waits for the child to finish and
1697          * continues execution normally. */
1698
1699         if (uid != 0 && uid_is_valid(uid)) {
1700                 r = asprintf(&uid_map,
1701                              "0 0 1\n"                      /* Map root → root */
1702                              UID_FMT " " UID_FMT " 1\n",    /* Map $UID → $UID */
1703                              uid, uid);
1704                 if (r < 0)
1705                         return -ENOMEM;
1706         } else {
1707                 uid_map = strdup("0 0 1\n");            /* The case where the above is the same */
1708                 if (!uid_map)
1709                         return -ENOMEM;
1710         }
1711
1712         if (gid != 0 && gid_is_valid(gid)) {
1713                 r = asprintf(&gid_map,
1714                              "0 0 1\n"                      /* Map root → root */
1715                              GID_FMT " " GID_FMT " 1\n",    /* Map $GID → $GID */
1716                              gid, gid);
1717                 if (r < 0)
1718                         return -ENOMEM;
1719         } else {
1720                 gid_map = strdup("0 0 1\n");            /* The case where the above is the same */
1721                 if (!gid_map)
1722                         return -ENOMEM;
1723         }
1724
1725         /* Create a communication channel so that the parent can tell the child when it finished creating the user
1726          * namespace. */
1727         unshare_ready_fd = eventfd(0, EFD_CLOEXEC);
1728         if (unshare_ready_fd < 0)
1729                 return -errno;
1730
1731         /* Create a communication channel so that the child can tell the parent a proper error code in case it
1732          * failed. */
1733         if (pipe2(errno_pipe, O_CLOEXEC) < 0)
1734                 return -errno;
1735
1736         pid = fork();
1737         if (pid < 0)
1738                 return -errno;
1739
1740         if (pid == 0) {
1741                 _cleanup_close_ int fd = -1;
1742                 const char *a;
1743                 pid_t ppid;
1744
1745                 /* Child process, running in the original user namespace. Let's update the parent's UID/GID map from
1746                  * here, after the parent opened its own user namespace. */
1747
1748                 ppid = getppid();
1749                 errno_pipe[0] = safe_close(errno_pipe[0]);
1750
1751                 /* Wait until the parent unshared the user namespace */
1752                 if (read(unshare_ready_fd, &c, sizeof(c)) < 0) {
1753                         r = -errno;
1754                         goto child_fail;
1755                 }
1756
1757                 /* Disable the setgroups() system call in the child user namespace, for good. */
1758                 a = procfs_file_alloca(ppid, "setgroups");
1759                 fd = open(a, O_WRONLY|O_CLOEXEC);
1760                 if (fd < 0) {
1761                         if (errno != ENOENT) {
1762                                 r = -errno;
1763                                 goto child_fail;
1764                         }
1765
1766                         /* If the file is missing the kernel is too old, let's continue anyway. */
1767                 } else {
1768                         if (write(fd, "deny\n", 5) < 0) {
1769                                 r = -errno;
1770                                 goto child_fail;
1771                         }
1772
1773                         fd = safe_close(fd);
1774                 }
1775
1776                 /* First write the GID map */
1777                 a = procfs_file_alloca(ppid, "gid_map");
1778                 fd = open(a, O_WRONLY|O_CLOEXEC);
1779                 if (fd < 0) {
1780                         r = -errno;
1781                         goto child_fail;
1782                 }
1783                 if (write(fd, gid_map, strlen(gid_map)) < 0) {
1784                         r = -errno;
1785                         goto child_fail;
1786                 }
1787                 fd = safe_close(fd);
1788
1789                 /* The write the UID map */
1790                 a = procfs_file_alloca(ppid, "uid_map");
1791                 fd = open(a, O_WRONLY|O_CLOEXEC);
1792                 if (fd < 0) {
1793                         r = -errno;
1794                         goto child_fail;
1795                 }
1796                 if (write(fd, uid_map, strlen(uid_map)) < 0) {
1797                         r = -errno;
1798                         goto child_fail;
1799                 }
1800
1801                 _exit(EXIT_SUCCESS);
1802
1803         child_fail:
1804                 (void) write(errno_pipe[1], &r, sizeof(r));
1805                 _exit(EXIT_FAILURE);
1806         }
1807
1808         errno_pipe[1] = safe_close(errno_pipe[1]);
1809
1810         if (unshare(CLONE_NEWUSER) < 0)
1811                 return -errno;
1812
1813         /* Let the child know that the namespace is ready now */
1814         if (write(unshare_ready_fd, &c, sizeof(c)) < 0)
1815                 return -errno;
1816
1817         /* Try to read an error code from the child */
1818         n = read(errno_pipe[0], &r, sizeof(r));
1819         if (n < 0)
1820                 return -errno;
1821         if (n == sizeof(r)) { /* an error code was sent to us */
1822                 if (r < 0)
1823                         return r;
1824                 return -EIO;
1825         }
1826         if (n != 0) /* on success we should have read 0 bytes */
1827                 return -EIO;
1828
1829         r = wait_for_terminate(pid, &si);
1830         if (r < 0)
1831                 return r;
1832         pid = 0;
1833
1834         /* If something strange happened with the child, let's consider this fatal, too */
1835         if (si.si_code != CLD_EXITED || si.si_status != 0)
1836                 return -EIO;
1837
1838         return 0;
1839 }
1840
1841 static int setup_runtime_directory(
1842                 const ExecContext *context,
1843                 const ExecParameters *params,
1844                 uid_t uid,
1845                 gid_t gid) {
1846
1847         char **rt;
1848         int r;
1849
1850         assert(context);
1851         assert(params);
1852
1853         STRV_FOREACH(rt, context->runtime_directory) {
1854                 _cleanup_free_ char *p;
1855
1856                 p = strjoin(params->runtime_prefix, "/", *rt);
1857                 if (!p)
1858                         return -ENOMEM;
1859
1860                 r = mkdir_p_label(p, context->runtime_directory_mode);
1861                 if (r < 0)
1862                         return r;
1863
1864                 r = chmod_and_chown(p, context->runtime_directory_mode, uid, gid);
1865                 if (r < 0)
1866                         return r;
1867         }
1868
1869         return 0;
1870 }
1871
1872 static int setup_smack(
1873                 const ExecContext *context,
1874                 const ExecCommand *command) {
1875
1876 #ifdef HAVE_SMACK
1877         int r;
1878
1879         assert(context);
1880         assert(command);
1881
1882         if (!mac_smack_use())
1883                 return 0;
1884
1885         if (context->smack_process_label) {
1886                 r = mac_smack_apply_pid(0, context->smack_process_label);
1887                 if (r < 0)
1888                         return r;
1889         }
1890 #ifdef SMACK_DEFAULT_PROCESS_LABEL
1891         else {
1892                 _cleanup_free_ char *exec_label = NULL;
1893
1894                 r = mac_smack_read(command->path, SMACK_ATTR_EXEC, &exec_label);
1895                 if (r < 0 && r != -ENODATA && r != -EOPNOTSUPP)
1896                         return r;
1897
1898                 r = mac_smack_apply_pid(0, exec_label ? : SMACK_DEFAULT_PROCESS_LABEL);
1899                 if (r < 0)
1900                         return r;
1901         }
1902 #endif
1903 #endif
1904
1905         return 0;
1906 }
1907
1908 static int compile_read_write_paths(
1909                 const ExecContext *context,
1910                 const ExecParameters *params,
1911                 char ***ret) {
1912
1913         _cleanup_strv_free_ char **l = NULL;
1914         char **rt;
1915
1916         /* Compile the list of writable paths. This is the combination of
1917          * the explicitly configured paths, plus all runtime directories. */
1918
1919         if (strv_isempty(context->read_write_paths) &&
1920             strv_isempty(context->runtime_directory)) {
1921                 *ret = NULL; /* NOP if neither is set */
1922                 return 0;
1923         }
1924
1925         l = strv_copy(context->read_write_paths);
1926         if (!l)
1927                 return -ENOMEM;
1928
1929         STRV_FOREACH(rt, context->runtime_directory) {
1930                 char *s;
1931
1932                 s = strjoin(params->runtime_prefix, "/", *rt);
1933                 if (!s)
1934                         return -ENOMEM;
1935
1936                 if (strv_consume(&l, s) < 0)
1937                         return -ENOMEM;
1938         }
1939
1940         *ret = l;
1941         l = NULL;
1942
1943         return 0;
1944 }
1945
1946 static int apply_mount_namespace(
1947                 Unit *u,
1948                 ExecCommand *command,
1949                 const ExecContext *context,
1950                 const ExecParameters *params,
1951                 ExecRuntime *runtime) {
1952
1953         _cleanup_strv_free_ char **rw = NULL;
1954         char *tmp = NULL, *var = NULL;
1955         const char *root_dir = NULL, *root_image = NULL;
1956         NameSpaceInfo ns_info = {
1957                 .ignore_protect_paths = false,
1958                 .private_dev = context->private_devices,
1959                 .protect_control_groups = context->protect_control_groups,
1960                 .protect_kernel_tunables = context->protect_kernel_tunables,
1961                 .protect_kernel_modules = context->protect_kernel_modules,
1962                 .mount_apivfs = context->mount_apivfs,
1963         };
1964         bool apply_restrictions;
1965         int r;
1966
1967         assert(context);
1968
1969         /* The runtime struct only contains the parent of the private /tmp,
1970          * which is non-accessible to world users. Inside of it there's a /tmp
1971          * that is sticky, and that's the one we want to use here. */
1972
1973         if (context->private_tmp && runtime) {
1974                 if (runtime->tmp_dir)
1975                         tmp = strjoina(runtime->tmp_dir, "/tmp");
1976                 if (runtime->var_tmp_dir)
1977                         var = strjoina(runtime->var_tmp_dir, "/tmp");
1978         }
1979
1980         r = compile_read_write_paths(context, params, &rw);
1981         if (r < 0)
1982                 return r;
1983
1984         if (params->flags & EXEC_APPLY_CHROOT) {
1985                 root_image = context->root_image;
1986
1987                 if (!root_image)
1988                         root_dir = context->root_directory;
1989         }
1990
1991         /*
1992          * If DynamicUser=no and RootDirectory= is set then lets pass a relaxed
1993          * sandbox info, otherwise enforce it, don't ignore protected paths and
1994          * fail if we are enable to apply the sandbox inside the mount namespace.
1995          */
1996         if (!context->dynamic_user && root_dir)
1997                 ns_info.ignore_protect_paths = true;
1998
1999         apply_restrictions = (params->flags & EXEC_APPLY_PERMISSIONS) && !command->privileged;
2000
2001         r = setup_namespace(root_dir, root_image,
2002                             &ns_info, rw,
2003                             apply_restrictions ? context->read_only_paths : NULL,
2004                             apply_restrictions ? context->inaccessible_paths : NULL,
2005                             context->bind_mounts,
2006                             context->n_bind_mounts,
2007                             tmp,
2008                             var,
2009                             apply_restrictions ? context->protect_home : PROTECT_HOME_NO,
2010                             apply_restrictions ? context->protect_system : PROTECT_SYSTEM_NO,
2011                             context->mount_flags,
2012                             DISSECT_IMAGE_DISCARD_ON_LOOP);
2013
2014         /* If we couldn't set up the namespace this is probably due to a
2015          * missing capability. In this case, silently proceeed. */
2016         if (IN_SET(r, -EPERM, -EACCES)) {
2017                 log_open();
2018                 log_unit_debug_errno(u, r, "Failed to set up namespace, assuming containerized execution, ignoring: %m");
2019                 log_close();
2020                 r = 0;
2021         }
2022
2023         return r;
2024 }
2025
2026 static int apply_working_directory(
2027                 const ExecContext *context,
2028                 const ExecParameters *params,
2029                 const char *home,
2030                 const bool needs_mount_ns,
2031                 int *exit_status) {
2032
2033         const char *d, *wd;
2034
2035         assert(context);
2036         assert(exit_status);
2037
2038         if (context->working_directory_home) {
2039
2040                 if (!home) {
2041                         *exit_status = EXIT_CHDIR;
2042                         return -ENXIO;
2043                 }
2044
2045                 wd = home;
2046
2047         } else if (context->working_directory)
2048                 wd = context->working_directory;
2049         else
2050                 wd = "/";
2051
2052         if (params->flags & EXEC_APPLY_CHROOT) {
2053                 if (!needs_mount_ns && context->root_directory)
2054                         if (chroot(context->root_directory) < 0) {
2055                                 *exit_status = EXIT_CHROOT;
2056                                 return -errno;
2057                         }
2058
2059                 d = wd;
2060         } else
2061                 d = prefix_roota(context->root_directory, wd);
2062
2063         if (chdir(d) < 0 && !context->working_directory_missing_ok) {
2064                 *exit_status = EXIT_CHDIR;
2065                 return -errno;
2066         }
2067
2068         return 0;
2069 }
2070
2071 static int setup_keyring(Unit *u, const ExecParameters *p, uid_t uid, gid_t gid) {
2072         key_serial_t keyring;
2073
2074         assert(u);
2075         assert(p);
2076
2077         /* Let's set up a new per-service "session" kernel keyring for each system service. This has the benefit that
2078          * each service runs with its own keyring shared among all processes of the service, but with no hook-up beyond
2079          * that scope, and in particular no link to the per-UID keyring. If we don't do this the keyring will be
2080          * automatically created on-demand and then linked to the per-UID keyring, by the kernel. The kernel's built-in
2081          * on-demand behaviour is very appropriate for login users, but probably not so much for system services, where
2082          * UIDs are not necessarily specific to a service but reused (at least in the case of UID 0). */
2083
2084         if (!(p->flags & EXEC_NEW_KEYRING))
2085                 return 0;
2086
2087         keyring = keyctl(KEYCTL_JOIN_SESSION_KEYRING, 0, 0, 0, 0);
2088         if (keyring == -1) {
2089                 if (errno == ENOSYS)
2090                         log_debug_errno(errno, "Kernel keyring not supported, ignoring.");
2091                 else if (IN_SET(errno, EACCES, EPERM))
2092                         log_debug_errno(errno, "Kernel keyring access prohibited, ignoring.");
2093                 else if (errno == EDQUOT)
2094                         log_debug_errno(errno, "Out of kernel keyrings to allocate, ignoring.");
2095                 else
2096                         return log_error_errno(errno, "Setting up kernel keyring failed: %m");
2097
2098                 return 0;
2099         }
2100
2101         /* Populate they keyring with the invocation ID by default. */
2102         if (!sd_id128_is_null(u->invocation_id)) {
2103                 key_serial_t key;
2104
2105                 key = add_key("user", "invocation_id", &u->invocation_id, sizeof(u->invocation_id), KEY_SPEC_SESSION_KEYRING);
2106                 if (key == -1)
2107                         log_debug_errno(errno, "Failed to add invocation ID to keyring, ignoring: %m");
2108                 else {
2109                         if (keyctl(KEYCTL_SETPERM, key,
2110                                    KEY_POS_VIEW|KEY_POS_READ|KEY_POS_SEARCH|
2111                                    KEY_USR_VIEW|KEY_USR_READ|KEY_USR_SEARCH, 0, 0) < 0)
2112                                 return log_error_errno(errno, "Failed to restrict invocation ID permission: %m");
2113                 }
2114         }
2115
2116         /* And now, make the keyring owned by the service's user */
2117         if (uid_is_valid(uid) || gid_is_valid(gid))
2118                 if (keyctl(KEYCTL_CHOWN, keyring, uid, gid, 0) < 0)
2119                         return log_error_errno(errno, "Failed to change ownership of session keyring: %m");
2120
2121         return 0;
2122 }
2123
2124 static void append_socket_pair(int *array, unsigned *n, int pair[2]) {
2125         assert(array);
2126         assert(n);
2127
2128         if (!pair)
2129                 return;
2130
2131         if (pair[0] >= 0)
2132                 array[(*n)++] = pair[0];
2133         if (pair[1] >= 0)
2134                 array[(*n)++] = pair[1];
2135 }
2136
2137 static int close_remaining_fds(
2138                 const ExecParameters *params,
2139                 ExecRuntime *runtime,
2140                 DynamicCreds *dcreds,
2141                 int user_lookup_fd,
2142                 int socket_fd,
2143                 int *fds, unsigned n_fds) {
2144
2145         unsigned n_dont_close = 0;
2146         int dont_close[n_fds + 12];
2147
2148         assert(params);
2149
2150         if (params->stdin_fd >= 0)
2151                 dont_close[n_dont_close++] = params->stdin_fd;
2152         if (params->stdout_fd >= 0)
2153                 dont_close[n_dont_close++] = params->stdout_fd;
2154         if (params->stderr_fd >= 0)
2155                 dont_close[n_dont_close++] = params->stderr_fd;
2156
2157         if (socket_fd >= 0)
2158                 dont_close[n_dont_close++] = socket_fd;
2159         if (n_fds > 0) {
2160                 memcpy(dont_close + n_dont_close, fds, sizeof(int) * n_fds);
2161                 n_dont_close += n_fds;
2162         }
2163
2164         if (runtime)
2165                 append_socket_pair(dont_close, &n_dont_close, runtime->netns_storage_socket);
2166
2167         if (dcreds) {
2168                 if (dcreds->user)
2169                         append_socket_pair(dont_close, &n_dont_close, dcreds->user->storage_socket);
2170                 if (dcreds->group)
2171                         append_socket_pair(dont_close, &n_dont_close, dcreds->group->storage_socket);
2172         }
2173
2174         if (user_lookup_fd >= 0)
2175                 dont_close[n_dont_close++] = user_lookup_fd;
2176
2177         return close_all_fds(dont_close, n_dont_close);
2178 }
2179
2180 static int send_user_lookup(
2181                 Unit *unit,
2182                 int user_lookup_fd,
2183                 uid_t uid,
2184                 gid_t gid) {
2185
2186         assert(unit);
2187
2188         /* Send the resolved UID/GID to PID 1 after we learnt it. We send a single datagram, containing the UID/GID
2189          * data as well as the unit name. Note that we suppress sending this if no user/group to resolve was
2190          * specified. */
2191
2192         if (user_lookup_fd < 0)
2193                 return 0;
2194
2195         if (!uid_is_valid(uid) && !gid_is_valid(gid))
2196                 return 0;
2197
2198         if (writev(user_lookup_fd,
2199                (struct iovec[]) {
2200                            { .iov_base = &uid, .iov_len = sizeof(uid) },
2201                            { .iov_base = &gid, .iov_len = sizeof(gid) },
2202                            { .iov_base = unit->id, .iov_len = strlen(unit->id) }}, 3) < 0)
2203                 return -errno;
2204
2205         return 0;
2206 }
2207
2208 static int acquire_home(const ExecContext *c, uid_t uid, const char** home, char **buf) {
2209         int r;
2210
2211         assert(c);
2212         assert(home);
2213         assert(buf);
2214
2215         /* If WorkingDirectory=~ is set, try to acquire a usable home directory. */
2216
2217         if (*home)
2218                 return 0;
2219
2220         if (!c->working_directory_home)
2221                 return 0;
2222
2223         if (uid == 0) {
2224                 /* Hardcode /root as home directory for UID 0 */
2225                 *home = "/root";
2226                 return 1;
2227         }
2228
2229         r = get_home_dir(buf);
2230         if (r < 0)
2231                 return r;
2232
2233         *home = *buf;
2234         return 1;
2235 }
2236
2237 static int exec_child(
2238                 Unit *unit,
2239                 ExecCommand *command,
2240                 const ExecContext *context,
2241                 const ExecParameters *params,
2242                 ExecRuntime *runtime,
2243                 DynamicCreds *dcreds,
2244                 char **argv,
2245                 int socket_fd,
2246                 int named_iofds[3],
2247                 int *fds, unsigned n_fds,
2248                 unsigned n_socket_fds,
2249                 char **files_env,
2250                 int user_lookup_fd,
2251                 int *exit_status,
2252                 char **error_message) {
2253
2254         _cleanup_strv_free_ char **our_env = NULL, **pass_env = NULL, **accum_env = NULL, **final_argv = NULL;
2255         _cleanup_free_ char *mac_selinux_context_net = NULL, *home_buffer = NULL;
2256         _cleanup_free_ gid_t *supplementary_gids = NULL;
2257         const char *username = NULL, *groupname = NULL;
2258         const char *home = NULL, *shell = NULL;
2259         dev_t journal_stream_dev = 0;
2260         ino_t journal_stream_ino = 0;
2261         bool needs_mount_namespace;
2262         uid_t uid = UID_INVALID;
2263         gid_t gid = GID_INVALID;
2264         int i, r, ngids = 0;
2265
2266         assert(unit);
2267         assert(command);
2268         assert(context);
2269         assert(params);
2270         assert(exit_status);
2271         assert(error_message);
2272         /* We don't always set error_message, hence it must be initialized */
2273         assert(*error_message == NULL);
2274
2275         rename_process_from_path(command->path);
2276
2277         /* We reset exactly these signals, since they are the
2278          * only ones we set to SIG_IGN in the main daemon. All
2279          * others we leave untouched because we set them to
2280          * SIG_DFL or a valid handler initially, both of which
2281          * will be demoted to SIG_DFL. */
2282         (void) default_signals(SIGNALS_CRASH_HANDLER,
2283                                SIGNALS_IGNORE, -1);
2284
2285         if (context->ignore_sigpipe)
2286                 (void) ignore_signals(SIGPIPE, -1);
2287
2288         r = reset_signal_mask();
2289         if (r < 0) {
2290                 *exit_status = EXIT_SIGNAL_MASK;
2291                 *error_message = strdup("Failed to reset signal mask");
2292                 /* If strdup fails, here and below, we will just print the generic error message. */
2293                 return r;
2294         }
2295
2296         if (params->idle_pipe)
2297                 do_idle_pipe_dance(params->idle_pipe);
2298
2299         /* Close sockets very early to make sure we don't
2300          * block init reexecution because it cannot bind its
2301          * sockets */
2302
2303         log_forget_fds();
2304
2305         r = close_remaining_fds(params, runtime, dcreds, user_lookup_fd, socket_fd, fds, n_fds);
2306         if (r < 0) {
2307                 *exit_status = EXIT_FDS;
2308                 *error_message = strdup("Failed to close remaining fds");
2309                 return r;
2310         }
2311
2312         if (!context->same_pgrp)
2313                 if (setsid() < 0) {
2314                         *exit_status = EXIT_SETSID;
2315                         return -errno;
2316                 }
2317
2318         exec_context_tty_reset(context, params);
2319
2320         if (unit_shall_confirm_spawn(unit)) {
2321                 const char *vc = params->confirm_spawn;
2322                 _cleanup_free_ char *cmdline = NULL;
2323
2324                 cmdline = exec_command_line(argv);
2325                 if (!cmdline) {
2326                         *exit_status = EXIT_CONFIRM;
2327                         return -ENOMEM;
2328                 }
2329
2330                 r = ask_for_confirmation(vc, unit, cmdline);
2331                 if (r != CONFIRM_EXECUTE) {
2332                         if (r == CONFIRM_PRETEND_SUCCESS) {
2333                                 *exit_status = EXIT_SUCCESS;
2334                                 return 0;
2335                         }
2336                         *exit_status = EXIT_CONFIRM;
2337                         *error_message = strdup("Execution cancelled");
2338                         return -ECANCELED;
2339                 }
2340         }
2341
2342         if (context->dynamic_user && dcreds) {
2343
2344                 /* Make sure we bypass our own NSS module for any NSS checks */
2345                 if (putenv((char*) "SYSTEMD_NSS_DYNAMIC_BYPASS=1") != 0) {
2346                         *exit_status = EXIT_USER;
2347                         *error_message = strdup("Failed to update environment");
2348                         return -errno;
2349                 }
2350
2351                 r = dynamic_creds_realize(dcreds, &uid, &gid);
2352                 if (r < 0) {
2353                         *exit_status = EXIT_USER;
2354                         *error_message = strdup("Failed to update dynamic user credentials");
2355                         return r;
2356                 }
2357
2358                 if (!uid_is_valid(uid)) {
2359                         *exit_status = EXIT_USER;
2360                         (void) asprintf(error_message, "UID validation failed for \""UID_FMT"\"", uid);
2361                         /* If asprintf fails, here and below, we will just print the generic error message. */
2362                         return -ESRCH;
2363                 }
2364
2365                 if (!gid_is_valid(gid)) {
2366                         *exit_status = EXIT_USER;
2367                         (void) asprintf(error_message, "GID validation failed for \""GID_FMT"\"", gid);
2368                         return -ESRCH;
2369                 }
2370
2371                 if (dcreds->user)
2372                         username = dcreds->user->name;
2373
2374         } else {
2375                 r = get_fixed_user(context, &username, &uid, &gid, &home, &shell);
2376                 if (r < 0) {
2377                         *exit_status = EXIT_USER;
2378                         *error_message = strdup("Failed to determine user credentials");
2379                         return r;
2380                 }
2381
2382                 r = get_fixed_group(context, &groupname, &gid);
2383                 if (r < 0) {
2384                         *exit_status = EXIT_GROUP;
2385                         *error_message = strdup("Failed to determine group credentials");
2386                         return r;
2387                 }
2388         }
2389
2390         /* Initialize user supplementary groups and get SupplementaryGroups= ones */
2391         r = get_supplementary_groups(context, username, groupname, gid,
2392                                      &supplementary_gids, &ngids);
2393         if (r < 0) {
2394                 *exit_status = EXIT_GROUP;
2395                 *error_message = strdup("Failed to determine supplementary groups");
2396                 return r;
2397         }
2398
2399         r = send_user_lookup(unit, user_lookup_fd, uid, gid);
2400         if (r < 0) {
2401                 *exit_status = EXIT_USER;
2402                 *error_message = strdup("Failed to send user credentials to PID1");
2403                 return r;
2404         }
2405
2406         user_lookup_fd = safe_close(user_lookup_fd);
2407
2408         r = acquire_home(context, uid, &home, &home_buffer);
2409         if (r < 0) {
2410                 *exit_status = EXIT_CHDIR;
2411                 *error_message = strdup("Failed to determine $HOME for user");
2412                 return r;
2413         }
2414
2415         /* If a socket is connected to STDIN/STDOUT/STDERR, we
2416          * must sure to drop O_NONBLOCK */
2417         if (socket_fd >= 0)
2418                 (void) fd_nonblock(socket_fd, false);
2419
2420         r = setup_input(context, params, socket_fd, named_iofds);
2421         if (r < 0) {
2422                 *exit_status = EXIT_STDIN;
2423                 *error_message = strdup("Failed to set up stdin");
2424                 return r;
2425         }
2426
2427         r = setup_output(unit, context, params, STDOUT_FILENO, socket_fd, named_iofds, basename(command->path), uid, gid, &journal_stream_dev, &journal_stream_ino);
2428         if (r < 0) {
2429                 *exit_status = EXIT_STDOUT;
2430                 *error_message = strdup("Failed to set up stdout");
2431                 return r;
2432         }
2433
2434         r = setup_output(unit, context, params, STDERR_FILENO, socket_fd, named_iofds, basename(command->path), uid, gid, &journal_stream_dev, &journal_stream_ino);
2435         if (r < 0) {
2436                 *exit_status = EXIT_STDERR;
2437                 *error_message = strdup("Failed to set up stderr");
2438                 return r;
2439         }
2440
2441         if (params->cgroup_path) {
2442                 r = cg_attach_everywhere(params->cgroup_supported, params->cgroup_path, 0, NULL, NULL);
2443                 if (r < 0) {
2444                         *exit_status = EXIT_CGROUP;
2445                         (void) asprintf(error_message, "Failed to attach to cgroup %s", params->cgroup_path);
2446                         return r;
2447                 }
2448         }
2449
2450         if (context->oom_score_adjust_set) {
2451                 char t[DECIMAL_STR_MAX(context->oom_score_adjust)];
2452
2453                 /* When we can't make this change due to EPERM, then
2454                  * let's silently skip over it. User namespaces
2455                  * prohibit write access to this file, and we
2456                  * shouldn't trip up over that. */
2457
2458                 sprintf(t, "%i", context->oom_score_adjust);
2459                 r = write_string_file("/proc/self/oom_score_adj", t, 0);
2460                 if (r == -EPERM || r == -EACCES) {
2461                         log_open();
2462                         log_unit_debug_errno(unit, r, "Failed to adjust OOM setting, assuming containerized execution, ignoring: %m");
2463                         log_close();
2464                 } else if (r < 0) {
2465                         *exit_status = EXIT_OOM_ADJUST;
2466                         *error_message = strdup("Failed to write /proc/self/oom_score_adj");
2467                         return -errno;
2468                 }
2469         }
2470
2471         if (context->nice_set)
2472                 if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
2473                         *exit_status = EXIT_NICE;
2474                         return -errno;
2475                 }
2476
2477         if (context->cpu_sched_set) {
2478                 struct sched_param param = {
2479                         .sched_priority = context->cpu_sched_priority,
2480                 };
2481
2482                 r = sched_setscheduler(0,
2483                                        context->cpu_sched_policy |
2484                                        (context->cpu_sched_reset_on_fork ?
2485                                         SCHED_RESET_ON_FORK : 0),
2486                                        &param);
2487                 if (r < 0) {
2488                         *exit_status = EXIT_SETSCHEDULER;
2489                         return -errno;
2490                 }
2491         }
2492
2493         if (context->cpuset)
2494                 if (sched_setaffinity(0, CPU_ALLOC_SIZE(context->cpuset_ncpus), context->cpuset) < 0) {
2495                         *exit_status = EXIT_CPUAFFINITY;
2496                         return -errno;
2497                 }
2498
2499         if (context->ioprio_set)
2500                 if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
2501                         *exit_status = EXIT_IOPRIO;
2502                         return -errno;
2503                 }
2504
2505         if (context->timer_slack_nsec != NSEC_INFINITY)
2506                 if (prctl(PR_SET_TIMERSLACK, context->timer_slack_nsec) < 0) {
2507                         *exit_status = EXIT_TIMERSLACK;
2508                         return -errno;
2509                 }
2510
2511         if (context->personality != PERSONALITY_INVALID)
2512                 if (personality(context->personality) < 0) {
2513                         *exit_status = EXIT_PERSONALITY;
2514                         return -errno;
2515                 }
2516
2517         if (context->utmp_id)
2518                 utmp_put_init_process(context->utmp_id, getpid(), getsid(0),
2519                                       context->tty_path,
2520                                       context->utmp_mode == EXEC_UTMP_INIT  ? INIT_PROCESS :
2521                                       context->utmp_mode == EXEC_UTMP_LOGIN ? LOGIN_PROCESS :
2522                                       USER_PROCESS,
2523                                       username);
2524
2525         if (context->user) {
2526                 r = chown_terminal(STDIN_FILENO, uid);
2527                 if (r < 0) {
2528                         *exit_status = EXIT_STDIN;
2529                         return r;
2530                 }
2531         }
2532
2533         /* If delegation is enabled we'll pass ownership of the cgroup
2534          * (but only in systemd's own controller hierarchy!) to the
2535          * user of the new process. */
2536         if (params->cgroup_path && context->user && params->cgroup_delegate) {
2537                 r = cg_set_task_access(SYSTEMD_CGROUP_CONTROLLER, params->cgroup_path, 0644, uid, gid);
2538                 if (r < 0) {
2539                         *exit_status = EXIT_CGROUP;
2540                         return r;
2541                 }
2542
2543
2544                 r = cg_set_group_access(SYSTEMD_CGROUP_CONTROLLER, params->cgroup_path, 0755, uid, gid);
2545                 if (r < 0) {
2546                         *exit_status = EXIT_CGROUP;
2547                         return r;
2548                 }
2549         }
2550
2551         if (!strv_isempty(context->runtime_directory) && params->runtime_prefix) {
2552                 r = setup_runtime_directory(context, params, uid, gid);
2553                 if (r < 0) {
2554                         *exit_status = EXIT_RUNTIME_DIRECTORY;
2555                         return r;
2556                 }
2557         }
2558
2559         r = build_environment(
2560                         unit,
2561                         context,
2562                         params,
2563                         n_fds,
2564                         home,
2565                         username,
2566                         shell,
2567                         journal_stream_dev,
2568                         journal_stream_ino,
2569                         &our_env);
2570         if (r < 0) {
2571                 *exit_status = EXIT_MEMORY;
2572                 return r;
2573         }
2574
2575         r = build_pass_environment(context, &pass_env);
2576         if (r < 0) {
2577                 *exit_status = EXIT_MEMORY;
2578                 return r;
2579         }
2580
2581         accum_env = strv_env_merge(5,
2582                                    params->environment,
2583                                    our_env,
2584                                    pass_env,
2585                                    context->environment,
2586                                    files_env,
2587                                    NULL);
2588         if (!accum_env) {
2589                 *exit_status = EXIT_MEMORY;
2590                 return -ENOMEM;
2591         }
2592         accum_env = strv_env_clean(accum_env);
2593
2594         (void) umask(context->umask);
2595
2596         r = setup_keyring(unit, params, uid, gid);
2597         if (r < 0) {
2598                 *exit_status = EXIT_KEYRING;
2599                 return r;
2600         }
2601
2602         if ((params->flags & EXEC_APPLY_PERMISSIONS) && !command->privileged) {
2603                 if (context->pam_name && username) {
2604                         r = setup_pam(context->pam_name, username, uid, gid, context->tty_path, &accum_env, fds, n_fds);
2605                         if (r < 0) {
2606                                 *exit_status = EXIT_PAM;
2607                                 return r;
2608                         }
2609                 }
2610         }
2611
2612         if (context->private_network && runtime && runtime->netns_storage_socket[0] >= 0) {
2613                 r = setup_netns(runtime->netns_storage_socket);
2614                 if (r < 0) {
2615                         *exit_status = EXIT_NETWORK;
2616                         return r;
2617                 }
2618         }
2619
2620         needs_mount_namespace = exec_needs_mount_namespace(context, params, runtime);
2621         if (needs_mount_namespace) {
2622                 r = apply_mount_namespace(unit, command, context, params, runtime);
2623                 if (r < 0) {
2624                         *exit_status = EXIT_NAMESPACE;
2625                         return r;
2626                 }
2627         }
2628
2629         /* Apply just after mount namespace setup */
2630         r = apply_working_directory(context, params, home, needs_mount_namespace, exit_status);
2631         if (r < 0)
2632                 return r;
2633
2634         /* Drop groups as early as possbile */
2635         if ((params->flags & EXEC_APPLY_PERMISSIONS) && !command->privileged) {
2636                 r = enforce_groups(context, gid, supplementary_gids, ngids);
2637                 if (r < 0) {
2638                         *exit_status = EXIT_GROUP;
2639                         return r;
2640                 }
2641         }
2642
2643 #ifdef HAVE_SELINUX
2644         if ((params->flags & EXEC_APPLY_PERMISSIONS) &&
2645             mac_selinux_use() &&
2646             params->selinux_context_net &&
2647             socket_fd >= 0 &&
2648             !command->privileged) {
2649
2650                 r = mac_selinux_get_child_mls_label(socket_fd, command->path, context->selinux_context, &mac_selinux_context_net);
2651                 if (r < 0) {
2652                         *exit_status = EXIT_SELINUX_CONTEXT;
2653                         return r;
2654                 }
2655         }
2656 #endif
2657
2658         if ((params->flags & EXEC_APPLY_PERMISSIONS) && context->private_users) {
2659                 r = setup_private_users(uid, gid);
2660                 if (r < 0) {
2661                         *exit_status = EXIT_USER;
2662                         return r;
2663                 }
2664         }
2665
2666         /* We repeat the fd closing here, to make sure that
2667          * nothing is leaked from the PAM modules. Note that
2668          * we are more aggressive this time since socket_fd
2669          * and the netns fds we don't need anymore. The custom
2670          * endpoint fd was needed to upload the policy and can
2671          * now be closed as well. */
2672         r = close_all_fds(fds, n_fds);
2673         if (r >= 0)
2674                 r = shift_fds(fds, n_fds);
2675         if (r >= 0)
2676                 r = flags_fds(fds, n_fds, n_socket_fds, context->non_blocking);
2677         if (r < 0) {
2678                 *exit_status = EXIT_FDS;
2679                 return r;
2680         }
2681
2682         if ((params->flags & EXEC_APPLY_PERMISSIONS) && !command->privileged) {
2683
2684                 int secure_bits = context->secure_bits;
2685
2686                 for (i = 0; i < _RLIMIT_MAX; i++) {
2687
2688                         if (!context->rlimit[i])
2689                                 continue;
2690
2691                         r = setrlimit_closest(i, context->rlimit[i]);
2692                         if (r < 0) {
2693                                 *exit_status = EXIT_LIMITS;
2694                                 return r;
2695                         }
2696                 }
2697
2698                 /* Set the RTPRIO resource limit to 0, but only if nothing else was explicitly requested. */
2699                 if (context->restrict_realtime && !context->rlimit[RLIMIT_RTPRIO]) {
2700                         if (setrlimit(RLIMIT_RTPRIO, &RLIMIT_MAKE_CONST(0)) < 0) {
2701                                 *exit_status = EXIT_LIMITS;
2702                                 return -errno;
2703                         }
2704                 }
2705
2706                 if (!cap_test_all(context->capability_bounding_set)) {
2707                         r = capability_bounding_set_drop(context->capability_bounding_set, false);
2708                         if (r < 0) {
2709                                 *exit_status = EXIT_CAPABILITIES;
2710                                 *error_message = strdup("Failed to drop capabilities");
2711                                 return r;
2712                         }
2713                 }
2714
2715                 /* This is done before enforce_user, but ambient set
2716                  * does not survive over setresuid() if keep_caps is not set. */
2717                 if (context->capability_ambient_set != 0) {
2718                         r = capability_ambient_set_apply(context->capability_ambient_set, true);
2719                         if (r < 0) {
2720                                 *exit_status = EXIT_CAPABILITIES;
2721                                 *error_message = strdup("Failed to apply ambient capabilities (before UID change)");
2722                                 return r;
2723                         }
2724                 }
2725
2726                 if (context->user) {
2727                         r = enforce_user(context, uid);
2728                         if (r < 0) {
2729                                 *exit_status = EXIT_USER;
2730                                 (void) asprintf(error_message, "Failed to change UID to "UID_FMT, uid);
2731                                 return r;
2732                         }
2733                         if (context->capability_ambient_set != 0) {
2734
2735                                 /* Fix the ambient capabilities after user change. */
2736                                 r = capability_ambient_set_apply(context->capability_ambient_set, false);
2737                                 if (r < 0) {
2738                                         *exit_status = EXIT_CAPABILITIES;
2739                                         *error_message = strdup("Failed to apply ambient capabilities (after UID change)");
2740                                         return r;
2741                                 }
2742
2743                                 /* If we were asked to change user and ambient capabilities
2744                                  * were requested, we had to add keep-caps to the securebits
2745                                  * so that we would maintain the inherited capability set
2746                                  * through the setresuid(). Make sure that the bit is added
2747                                  * also to the context secure_bits so that we don't try to
2748                                  * drop the bit away next. */
2749
2750                                 secure_bits |= 1<<SECURE_KEEP_CAPS;
2751                         }
2752                 }
2753
2754                 /* Apply the MAC contexts late, but before seccomp syscall filtering, as those should really be last to
2755                  * influence our own codepaths as little as possible. Moreover, applying MAC contexts usually requires
2756                  * syscalls that are subject to seccomp filtering, hence should probably be applied before the syscalls
2757                  * are restricted. */
2758
2759 #ifdef HAVE_SELINUX
2760                 if (mac_selinux_use()) {
2761                         char *exec_context = mac_selinux_context_net ?: context->selinux_context;
2762
2763                         if (exec_context) {
2764                                 r = setexeccon(exec_context);
2765                                 if (r < 0) {
2766                                         *exit_status = EXIT_SELINUX_CONTEXT;
2767                                         (void) asprintf(error_message, "Failed to set SELinux context to %s", exec_context);
2768                                         return r;
2769                                 }
2770                         }
2771                 }
2772 #endif
2773
2774                 r = setup_smack(context, command);
2775                 if (r < 0) {
2776                         *exit_status = EXIT_SMACK_PROCESS_LABEL;
2777                         *error_message = strdup("Failed to set SMACK process label");
2778                         return r;
2779                 }
2780
2781 #ifdef HAVE_APPARMOR
2782                 if (context->apparmor_profile && mac_apparmor_use()) {
2783                         r = aa_change_onexec(context->apparmor_profile);
2784                         if (r < 0 && !context->apparmor_profile_ignore) {
2785                                 *exit_status = EXIT_APPARMOR_PROFILE;
2786                                 (void) asprintf(error_message,
2787                                                 "Failed to prepare AppArmor profile change to %s",
2788                                                 context->apparmor_profile);
2789                                 return -errno;
2790                         }
2791                 }
2792 #endif
2793
2794                 /* PR_GET_SECUREBITS is not privileged, while
2795                  * PR_SET_SECUREBITS is. So to suppress
2796                  * potential EPERMs we'll try not to call
2797                  * PR_SET_SECUREBITS unless necessary. */
2798                 if (prctl(PR_GET_SECUREBITS) != secure_bits)
2799                         if (prctl(PR_SET_SECUREBITS, secure_bits) < 0) {
2800                                 *exit_status = EXIT_SECUREBITS;
2801                                 *error_message = strdup("Failed to set secure bits");
2802                                 return -errno;
2803                         }
2804
2805                 if (context_has_no_new_privileges(context))
2806                         if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) < 0) {
2807                                 *exit_status = EXIT_NO_NEW_PRIVILEGES;
2808                                 *error_message = strdup("Failed to disable new privileges");
2809                                 return -errno;
2810                         }
2811
2812 #ifdef HAVE_SECCOMP
2813                 r = apply_address_families(unit, context);
2814                 if (r < 0) {
2815                         *exit_status = EXIT_ADDRESS_FAMILIES;
2816                         *error_message = strdup("Failed to restrict address families");
2817                         return r;
2818                 }
2819
2820                 r = apply_memory_deny_write_execute(unit, context);
2821                 if (r < 0) {
2822                         *exit_status = EXIT_SECCOMP;
2823                         *error_message = strdup("Failed to disable writing to executable memory");
2824                         return r;
2825                 }
2826
2827                 r = apply_restrict_realtime(unit, context);
2828                 if (r < 0) {
2829                         *exit_status = EXIT_SECCOMP;
2830                         *error_message = strdup("Failed to apply realtime restrictions");
2831                         return r;
2832                 }
2833
2834                 r = apply_restrict_namespaces(unit, context);
2835                 if (r < 0) {
2836                         *exit_status = EXIT_SECCOMP;
2837                         *error_message = strdup("Failed to apply namespace restrictions");
2838                         return r;
2839                 }
2840
2841                 r = apply_protect_sysctl(unit, context);
2842                 if (r < 0) {
2843                         *exit_status = EXIT_SECCOMP;
2844                         *error_message = strdup("Failed to apply sysctl restrictions");
2845                         return r;
2846                 }
2847
2848                 r = apply_protect_kernel_modules(unit, context);
2849                 if (r < 0) {
2850                         *exit_status = EXIT_SECCOMP;
2851                         *error_message = strdup("Failed to apply module loading restrictions");
2852                         return r;
2853                 }
2854
2855                 r = apply_private_devices(unit, context);
2856                 if (r < 0) {
2857                         *exit_status = EXIT_SECCOMP;
2858                         *error_message = strdup("Failed to set up private devices");
2859                         return r;
2860                 }
2861
2862                 r = apply_syscall_archs(unit, context);
2863                 if (r < 0) {
2864                         *exit_status = EXIT_SECCOMP;
2865                         *error_message = strdup("Failed to apply syscall architecture restrictions");
2866                         return r;
2867                 }
2868
2869                 /* This really should remain the last step before the execve(), to make sure our own code is unaffected
2870                  * by the filter as little as possible. */
2871                 r = apply_syscall_filter(unit, context);
2872                 if (r < 0) {
2873                         *exit_status = EXIT_SECCOMP;
2874                         *error_message = strdup("Failed to apply syscall filters");
2875                         return r;
2876                 }
2877 #endif
2878         }
2879
2880         final_argv = replace_env_argv(argv, accum_env);
2881         if (!final_argv) {
2882                 *exit_status = EXIT_MEMORY;
2883                 *error_message = strdup("Failed to prepare process arguments");
2884                 return -ENOMEM;
2885         }
2886
2887         if (_unlikely_(log_get_max_level() >= LOG_DEBUG)) {
2888                 _cleanup_free_ char *line;
2889
2890                 line = exec_command_line(final_argv);
2891                 if (line) {
2892                         log_open();
2893                         log_struct(LOG_DEBUG,
2894                                    "EXECUTABLE=%s", command->path,
2895                                    LOG_UNIT_MESSAGE(unit, "Executing: %s", line),
2896                                    LOG_UNIT_ID(unit),
2897                                    NULL);
2898                         log_close();
2899                 }
2900         }
2901
2902         execve(command->path, final_argv, accum_env);
2903         *exit_status = EXIT_EXEC;
2904         return -errno;
2905 }
2906
2907 int exec_spawn(Unit *unit,
2908                ExecCommand *command,
2909                const ExecContext *context,
2910                const ExecParameters *params,
2911                ExecRuntime *runtime,
2912                DynamicCreds *dcreds,
2913                pid_t *ret) {
2914
2915         _cleanup_strv_free_ char **files_env = NULL;
2916         int *fds = NULL;
2917         unsigned n_fds = 0, n_socket_fds = 0;
2918         _cleanup_free_ char *line = NULL;
2919         int socket_fd, r;
2920         int named_iofds[3] = { -1, -1, -1 };
2921         char **argv;
2922         pid_t pid;
2923
2924         assert(unit);
2925         assert(command);
2926         assert(context);
2927         assert(ret);
2928         assert(params);
2929         assert(params->fds || params->n_fds <= 0);
2930
2931         if (context->std_input == EXEC_INPUT_SOCKET ||
2932             context->std_output == EXEC_OUTPUT_SOCKET ||
2933             context->std_error == EXEC_OUTPUT_SOCKET) {
2934
2935                 if (params->n_fds > 1) {
2936                         log_unit_error(unit, "Got more than one socket.");
2937                         return -EINVAL;
2938                 }
2939
2940                 if (params->n_fds == 0) {
2941                         log_unit_error(unit, "Got no socket.");
2942                         return -EINVAL;
2943                 }
2944
2945                 socket_fd = params->fds[0];
2946         } else {
2947                 socket_fd = -1;
2948                 fds = params->fds;
2949                 n_fds = params->n_fds;
2950                 n_socket_fds = params->n_socket_fds;
2951         }
2952
2953         r = exec_context_named_iofds(unit, context, params, named_iofds);
2954         if (r < 0)
2955                 return log_unit_error_errno(unit, r, "Failed to load a named file descriptor: %m");
2956
2957         r = exec_context_load_environment(unit, context, &files_env);
2958         if (r < 0)
2959                 return log_unit_error_errno(unit, r, "Failed to load environment files: %m");
2960
2961         argv = params->argv ?: command->argv;
2962         line = exec_command_line(argv);
2963         if (!line)
2964                 return log_oom();
2965
2966         log_struct(LOG_DEBUG,
2967                    LOG_UNIT_MESSAGE(unit, "About to execute: %s", line),
2968                    "EXECUTABLE=%s", command->path,
2969                    LOG_UNIT_ID(unit),
2970                    NULL);
2971         pid = fork();
2972         if (pid < 0)
2973                 return log_unit_error_errno(unit, errno, "Failed to fork: %m");
2974
2975         if (pid == 0) {
2976                 int exit_status;
2977                 _cleanup_free_ char *error_message = NULL;
2978
2979                 r = exec_child(unit,
2980                                command,
2981                                context,
2982                                params,
2983                                runtime,
2984                                dcreds,
2985                                argv,
2986                                socket_fd,
2987                                named_iofds,
2988                                fds, n_fds,
2989                                n_socket_fds,
2990                                files_env,
2991                                unit->manager->user_lookup_fds[1],
2992                                &exit_status,
2993                                &error_message);
2994                 if (r < 0) {
2995                         log_open();
2996                         if (error_message)
2997                                 log_struct_errno(LOG_ERR, r,
2998                                                  "MESSAGE_ID=" SD_MESSAGE_SPAWN_FAILED_STR,
2999                                                  LOG_UNIT_ID(unit),
3000                                                  LOG_UNIT_MESSAGE(unit, "%s: %m",
3001                                                                   error_message),
3002                                                  "EXECUTABLE=%s", command->path,
3003                                                  NULL);
3004                         else if (r == -ENOENT && command->ignore)
3005                                 log_struct_errno(LOG_INFO, r,
3006                                                  "MESSAGE_ID=" SD_MESSAGE_SPAWN_FAILED_STR,
3007                                                  LOG_UNIT_ID(unit),
3008                                                  LOG_UNIT_MESSAGE(unit, "Skipped spawning %s: %m",
3009                                                                   command->path),
3010                                                  "EXECUTABLE=%s", command->path,
3011                                                  NULL);
3012                         else
3013                                 log_struct_errno(LOG_ERR, r,
3014                                                  "MESSAGE_ID=" SD_MESSAGE_SPAWN_FAILED_STR,
3015                                                  LOG_UNIT_ID(unit),
3016                                                  LOG_UNIT_MESSAGE(unit, "Failed at step %s spawning %s: %m",
3017                                                                   exit_status_to_string(exit_status, EXIT_STATUS_SYSTEMD),
3018                                                                   command->path),
3019                                                  "EXECUTABLE=%s", command->path,
3020                                                  NULL);
3021                 }
3022
3023                 _exit(exit_status);
3024         }
3025
3026         log_unit_debug(unit, "Forked %s as "PID_FMT, command->path, pid);
3027
3028         /* We add the new process to the cgroup both in the child (so
3029          * that we can be sure that no user code is ever executed
3030          * outside of the cgroup) and in the parent (so that we can be
3031          * sure that when we kill the cgroup the process will be
3032          * killed too). */
3033         if (params->cgroup_path)
3034                 (void) cg_attach(SYSTEMD_CGROUP_CONTROLLER, params->cgroup_path, pid);
3035
3036         exec_status_start(&command->exec_status, pid);
3037
3038         *ret = pid;
3039         return 0;
3040 }
3041
3042 void exec_context_init(ExecContext *c) {
3043         assert(c);
3044
3045         c->umask = 0022;
3046         c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
3047         c->cpu_sched_policy = SCHED_OTHER;
3048         c->syslog_priority = LOG_DAEMON|LOG_INFO;
3049         c->syslog_level_prefix = true;
3050         c->ignore_sigpipe = true;
3051         c->timer_slack_nsec = NSEC_INFINITY;
3052         c->personality = PERSONALITY_INVALID;
3053         c->runtime_directory_mode = 0755;
3054         c->capability_bounding_set = CAP_ALL;
3055         c->restrict_namespaces = NAMESPACE_FLAGS_ALL;
3056 }
3057
3058 void exec_context_done(ExecContext *c) {
3059         unsigned l;
3060
3061         assert(c);
3062
3063         c->environment = strv_free(c->environment);
3064         c->environment_files = strv_free(c->environment_files);
3065         c->pass_environment = strv_free(c->pass_environment);
3066
3067         for (l = 0; l < ELEMENTSOF(c->rlimit); l++)
3068                 c->rlimit[l] = mfree(c->rlimit[l]);
3069
3070         for (l = 0; l < 3; l++)
3071                 c->stdio_fdname[l] = mfree(c->stdio_fdname[l]);
3072
3073         c->working_directory = mfree(c->working_directory);
3074         c->root_directory = mfree(c->root_directory);
3075         c->root_image = mfree(c->root_image);
3076         c->tty_path = mfree(c->tty_path);
3077         c->syslog_identifier = mfree(c->syslog_identifier);
3078         c->user = mfree(c->user);
3079         c->group = mfree(c->group);
3080
3081         c->supplementary_groups = strv_free(c->supplementary_groups);
3082
3083         c->pam_name = mfree(c->pam_name);
3084
3085         c->read_only_paths = strv_free(c->read_only_paths);
3086         c->read_write_paths = strv_free(c->read_write_paths);
3087         c->inaccessible_paths = strv_free(c->inaccessible_paths);
3088
3089         bind_mount_free_many(c->bind_mounts, c->n_bind_mounts);
3090
3091         if (c->cpuset)
3092                 CPU_FREE(c->cpuset);
3093
3094         c->utmp_id = mfree(c->utmp_id);
3095         c->selinux_context = mfree(c->selinux_context);
3096         c->apparmor_profile = mfree(c->apparmor_profile);
3097
3098         c->syscall_filter = set_free(c->syscall_filter);
3099         c->syscall_archs = set_free(c->syscall_archs);
3100         c->address_families = set_free(c->address_families);
3101
3102         c->runtime_directory = strv_free(c->runtime_directory);
3103 }
3104
3105 int exec_context_destroy_runtime_directory(ExecContext *c, const char *runtime_prefix) {
3106         char **i;
3107
3108         assert(c);
3109
3110         if (!runtime_prefix)
3111                 return 0;
3112
3113         STRV_FOREACH(i, c->runtime_directory) {
3114                 _cleanup_free_ char *p;
3115
3116                 p = strjoin(runtime_prefix, "/", *i);
3117                 if (!p)
3118                         return -ENOMEM;
3119
3120                 /* We execute this synchronously, since we need to be
3121                  * sure this is gone when we start the service
3122                  * next. */
3123                 (void) rm_rf(p, REMOVE_ROOT);
3124         }
3125
3126         return 0;
3127 }
3128
3129 void exec_command_done(ExecCommand *c) {
3130         assert(c);
3131
3132         c->path = mfree(c->path);
3133
3134         c->argv = strv_free(c->argv);
3135 }
3136
3137 void exec_command_done_array(ExecCommand *c, unsigned n) {
3138         unsigned i;
3139
3140         for (i = 0; i < n; i++)
3141                 exec_command_done(c+i);
3142 }
3143
3144 ExecCommand* exec_command_free_list(ExecCommand *c) {
3145         ExecCommand *i;
3146
3147         while ((i = c)) {
3148                 LIST_REMOVE(command, c, i);
3149                 exec_command_done(i);
3150                 free(i);
3151         }
3152
3153         return NULL;
3154 }
3155
3156 void exec_command_free_array(ExecCommand **c, unsigned n) {
3157         unsigned i;
3158
3159         for (i = 0; i < n; i++)
3160                 c[i] = exec_command_free_list(c[i]);
3161 }
3162
3163 typedef struct InvalidEnvInfo {
3164         Unit *unit;
3165         const char *path;
3166 } InvalidEnvInfo;
3167
3168 static void invalid_env(const char *p, void *userdata) {
3169         InvalidEnvInfo *info = userdata;
3170
3171         log_unit_error(info->unit, "Ignoring invalid environment assignment '%s': %s", p, info->path);
3172 }
3173
3174 const char* exec_context_fdname(const ExecContext *c, int fd_index) {
3175         assert(c);
3176
3177         switch (fd_index) {
3178         case STDIN_FILENO:
3179                 if (c->std_input != EXEC_INPUT_NAMED_FD)
3180                         return NULL;
3181                 return c->stdio_fdname[STDIN_FILENO] ?: "stdin";
3182         case STDOUT_FILENO:
3183                 if (c->std_output != EXEC_OUTPUT_NAMED_FD)
3184                         return NULL;
3185                 return c->stdio_fdname[STDOUT_FILENO] ?: "stdout";
3186         case STDERR_FILENO:
3187                 if (c->std_error != EXEC_OUTPUT_NAMED_FD)
3188                         return NULL;
3189                 return c->stdio_fdname[STDERR_FILENO] ?: "stderr";
3190         default:
3191                 return NULL;
3192         }
3193 }
3194
3195 int exec_context_named_iofds(Unit *unit, const ExecContext *c, const ExecParameters *p, int named_iofds[3]) {
3196         unsigned i, targets;
3197         const char* stdio_fdname[3];
3198
3199         assert(c);
3200         assert(p);
3201
3202         targets = (c->std_input == EXEC_INPUT_NAMED_FD) +
3203                   (c->std_output == EXEC_OUTPUT_NAMED_FD) +
3204                   (c->std_error == EXEC_OUTPUT_NAMED_FD);
3205
3206         for (i = 0; i < 3; i++)
3207                 stdio_fdname[i] = exec_context_fdname(c, i);
3208
3209         for (i = 0; i < p->n_fds && targets > 0; i++)
3210                 if (named_iofds[STDIN_FILENO] < 0 &&
3211                     c->std_input == EXEC_INPUT_NAMED_FD &&
3212                     stdio_fdname[STDIN_FILENO] &&
3213                     streq(p->fd_names[i], stdio_fdname[STDIN_FILENO])) {
3214
3215                         named_iofds[STDIN_FILENO] = p->fds[i];
3216                         targets--;
3217
3218                 } else if (named_iofds[STDOUT_FILENO] < 0 &&
3219                            c->std_output == EXEC_OUTPUT_NAMED_FD &&
3220                            stdio_fdname[STDOUT_FILENO] &&
3221                            streq(p->fd_names[i], stdio_fdname[STDOUT_FILENO])) {
3222
3223                         named_iofds[STDOUT_FILENO] = p->fds[i];
3224                         targets--;
3225
3226                 } else if (named_iofds[STDERR_FILENO] < 0 &&
3227                            c->std_error == EXEC_OUTPUT_NAMED_FD &&
3228                            stdio_fdname[STDERR_FILENO] &&
3229                            streq(p->fd_names[i], stdio_fdname[STDERR_FILENO])) {
3230
3231                         named_iofds[STDERR_FILENO] = p->fds[i];
3232                         targets--;
3233                 }
3234
3235         return targets == 0 ? 0 : -ENOENT;
3236 }
3237
3238 int exec_context_load_environment(Unit *unit, const ExecContext *c, char ***l) {
3239         char **i, **r = NULL;
3240
3241         assert(c);
3242         assert(l);
3243
3244         STRV_FOREACH(i, c->environment_files) {
3245                 char *fn;
3246                 int k, n;
3247                 bool ignore = false;
3248                 char **p;
3249                 _cleanup_globfree_ glob_t pglob = {};
3250
3251                 fn = *i;
3252
3253                 if (fn[0] == '-') {
3254                         ignore = true;
3255                         fn++;
3256                 }
3257
3258                 if (!path_is_absolute(fn)) {
3259                         if (ignore)
3260                                 continue;
3261
3262                         strv_free(r);
3263                         return -EINVAL;
3264                 }
3265
3266                 /* Filename supports globbing, take all matching files */
3267                 k = safe_glob(fn, 0, &pglob);
3268                 if (k < 0) {
3269                         if (ignore)
3270                                 continue;
3271
3272                         strv_free(r);
3273                         return k;
3274                 }
3275
3276                 /* When we don't match anything, -ENOENT should be returned */
3277                 assert(pglob.gl_pathc > 0);
3278
3279                 for (n = 0; n < pglob.gl_pathc; n++) {
3280                         k = load_env_file(NULL, pglob.gl_pathv[n], NULL, &p);
3281                         if (k < 0) {
3282                                 if (ignore)
3283                                         continue;
3284
3285                                 strv_free(r);
3286                                 return k;
3287                         }
3288                         /* Log invalid environment variables with filename */
3289                         if (p) {
3290                                 InvalidEnvInfo info = {
3291                                         .unit = unit,
3292                                         .path = pglob.gl_pathv[n]
3293                                 };
3294
3295                                 p = strv_env_clean_with_callback(p, invalid_env, &info);
3296                         }
3297
3298                         if (r == NULL)
3299                                 r = p;
3300                         else {
3301                                 char **m;
3302
3303                                 m = strv_env_merge(2, r, p);
3304                                 strv_free(r);
3305                                 strv_free(p);
3306                                 if (!m)
3307                                         return -ENOMEM;
3308
3309                                 r = m;
3310                         }
3311                 }
3312         }
3313
3314         *l = r;
3315
3316         return 0;
3317 }
3318
3319 static bool tty_may_match_dev_console(const char *tty) {
3320         _cleanup_free_ char *active = NULL;
3321         char *console;
3322
3323         if (!tty)
3324                 return true;
3325
3326         if (startswith(tty, "/dev/"))
3327                 tty += 5;
3328
3329         /* trivial identity? */
3330         if (streq(tty, "console"))
3331                 return true;
3332
3333         console = resolve_dev_console(&active);
3334         /* if we could not resolve, assume it may */
3335         if (!console)
3336                 return true;
3337
3338         /* "tty0" means the active VC, so it may be the same sometimes */
3339         return streq(console, tty) || (streq(console, "tty0") && tty_is_vc(tty));
3340 }
3341
3342 bool exec_context_may_touch_console(ExecContext *ec) {
3343
3344         return (ec->tty_reset ||
3345                 ec->tty_vhangup ||
3346                 ec->tty_vt_disallocate ||
3347                 is_terminal_input(ec->std_input) ||
3348                 is_terminal_output(ec->std_output) ||
3349                 is_terminal_output(ec->std_error)) &&
3350                tty_may_match_dev_console(exec_context_tty_path(ec));
3351 }
3352
3353 static void strv_fprintf(FILE *f, char **l) {
3354         char **g;
3355
3356         assert(f);
3357
3358         STRV_FOREACH(g, l)
3359                 fprintf(f, " %s", *g);
3360 }
3361
3362 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
3363         char **e, **d;
3364         unsigned i;
3365         int r;
3366
3367         assert(c);
3368         assert(f);
3369
3370         prefix = strempty(prefix);
3371
3372         fprintf(f,
3373                 "%sUMask: %04o\n"
3374                 "%sWorkingDirectory: %s\n"
3375                 "%sRootDirectory: %s\n"
3376                 "%sNonBlocking: %s\n"
3377                 "%sPrivateTmp: %s\n"
3378                 "%sPrivateDevices: %s\n"
3379                 "%sProtectKernelTunables: %s\n"
3380                 "%sProtectKernelModules: %s\n"
3381                 "%sProtectControlGroups: %s\n"
3382                 "%sPrivateNetwork: %s\n"
3383                 "%sPrivateUsers: %s\n"
3384                 "%sProtectHome: %s\n"
3385                 "%sProtectSystem: %s\n"
3386                 "%sMountAPIVFS: %s\n"
3387                 "%sIgnoreSIGPIPE: %s\n"
3388                 "%sMemoryDenyWriteExecute: %s\n"
3389                 "%sRestrictRealtime: %s\n",
3390                 prefix, c->umask,
3391                 prefix, c->working_directory ? c->working_directory : "/",
3392                 prefix, c->root_directory ? c->root_directory : "/",
3393                 prefix, yes_no(c->non_blocking),
3394                 prefix, yes_no(c->private_tmp),
3395                 prefix, yes_no(c->private_devices),
3396                 prefix, yes_no(c->protect_kernel_tunables),
3397                 prefix, yes_no(c->protect_kernel_modules),
3398                 prefix, yes_no(c->protect_control_groups),
3399                 prefix, yes_no(c->private_network),
3400                 prefix, yes_no(c->private_users),
3401                 prefix, protect_home_to_string(c->protect_home),
3402                 prefix, protect_system_to_string(c->protect_system),
3403                 prefix, yes_no(c->mount_apivfs),
3404                 prefix, yes_no(c->ignore_sigpipe),
3405                 prefix, yes_no(c->memory_deny_write_execute),
3406                 prefix, yes_no(c->restrict_realtime));
3407
3408         if (c->root_image)
3409                 fprintf(f, "%sRootImage: %s\n", prefix, c->root_image);
3410
3411         STRV_FOREACH(e, c->environment)
3412                 fprintf(f, "%sEnvironment: %s\n", prefix, *e);
3413
3414         STRV_FOREACH(e, c->environment_files)
3415                 fprintf(f, "%sEnvironmentFile: %s\n", prefix, *e);
3416
3417         STRV_FOREACH(e, c->pass_environment)
3418                 fprintf(f, "%sPassEnvironment: %s\n", prefix, *e);
3419
3420         fprintf(f, "%sRuntimeDirectoryMode: %04o\n", prefix, c->runtime_directory_mode);
3421
3422         STRV_FOREACH(d, c->runtime_directory)
3423                 fprintf(f, "%sRuntimeDirectory: %s\n", prefix, *d);
3424
3425         if (c->nice_set)
3426                 fprintf(f,
3427                         "%sNice: %i\n",
3428                         prefix, c->nice);
3429
3430         if (c->oom_score_adjust_set)
3431                 fprintf(f,
3432                         "%sOOMScoreAdjust: %i\n",
3433                         prefix, c->oom_score_adjust);
3434
3435         for (i = 0; i < RLIM_NLIMITS; i++)
3436                 if (c->rlimit[i]) {
3437                         fprintf(f, "%s%s: " RLIM_FMT "\n",
3438                                 prefix, rlimit_to_string(i), c->rlimit[i]->rlim_max);
3439                         fprintf(f, "%s%sSoft: " RLIM_FMT "\n",
3440                                 prefix, rlimit_to_string(i), c->rlimit[i]->rlim_cur);
3441                 }
3442
3443         if (c->ioprio_set) {
3444                 _cleanup_free_ char *class_str = NULL;
3445
3446                 ioprio_class_to_string_alloc(IOPRIO_PRIO_CLASS(c->ioprio), &class_str);
3447                 fprintf(f,
3448                         "%sIOSchedulingClass: %s\n"
3449                         "%sIOPriority: %i\n",
3450                         prefix, strna(class_str),
3451                         prefix, (int) IOPRIO_PRIO_DATA(c->ioprio));
3452         }
3453
3454         if (c->cpu_sched_set) {
3455                 _cleanup_free_ char *policy_str = NULL;
3456
3457                 sched_policy_to_string_alloc(c->cpu_sched_policy, &policy_str);
3458                 fprintf(f,
3459                         "%sCPUSchedulingPolicy: %s\n"
3460                         "%sCPUSchedulingPriority: %i\n"
3461                         "%sCPUSchedulingResetOnFork: %s\n",
3462                         prefix, strna(policy_str),
3463                         prefix, c->cpu_sched_priority,
3464                         prefix, yes_no(c->cpu_sched_reset_on_fork));
3465         }
3466
3467         if (c->cpuset) {
3468                 fprintf(f, "%sCPUAffinity:", prefix);
3469                 for (i = 0; i < c->cpuset_ncpus; i++)
3470                         if (CPU_ISSET_S(i, CPU_ALLOC_SIZE(c->cpuset_ncpus), c->cpuset))
3471                                 fprintf(f, " %u", i);
3472                 fputs("\n", f);
3473         }
3474
3475         if (c->timer_slack_nsec != NSEC_INFINITY)
3476                 fprintf(f, "%sTimerSlackNSec: "NSEC_FMT "\n", prefix, c->timer_slack_nsec);
3477
3478         fprintf(f,
3479                 "%sStandardInput: %s\n"
3480                 "%sStandardOutput: %s\n"
3481                 "%sStandardError: %s\n",
3482                 prefix, exec_input_to_string(c->std_input),
3483                 prefix, exec_output_to_string(c->std_output),
3484                 prefix, exec_output_to_string(c->std_error));
3485
3486         if (c->tty_path)
3487                 fprintf(f,
3488                         "%sTTYPath: %s\n"
3489                         "%sTTYReset: %s\n"
3490                         "%sTTYVHangup: %s\n"
3491                         "%sTTYVTDisallocate: %s\n",
3492                         prefix, c->tty_path,
3493                         prefix, yes_no(c->tty_reset),
3494                         prefix, yes_no(c->tty_vhangup),
3495                         prefix, yes_no(c->tty_vt_disallocate));
3496
3497         if (c->std_output == EXEC_OUTPUT_SYSLOG ||
3498             c->std_output == EXEC_OUTPUT_KMSG ||
3499             c->std_output == EXEC_OUTPUT_JOURNAL ||
3500             c->std_output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE ||
3501             c->std_output == EXEC_OUTPUT_KMSG_AND_CONSOLE ||
3502             c->std_output == EXEC_OUTPUT_JOURNAL_AND_CONSOLE ||
3503             c->std_error == EXEC_OUTPUT_SYSLOG ||
3504             c->std_error == EXEC_OUTPUT_KMSG ||
3505             c->std_error == EXEC_OUTPUT_JOURNAL ||
3506             c->std_error == EXEC_OUTPUT_SYSLOG_AND_CONSOLE ||
3507             c->std_error == EXEC_OUTPUT_KMSG_AND_CONSOLE ||
3508             c->std_error == EXEC_OUTPUT_JOURNAL_AND_CONSOLE) {
3509
3510                 _cleanup_free_ char *fac_str = NULL, *lvl_str = NULL;
3511
3512                 log_facility_unshifted_to_string_alloc(c->syslog_priority >> 3, &fac_str);
3513                 log_level_to_string_alloc(LOG_PRI(c->syslog_priority), &lvl_str);
3514
3515                 fprintf(f,
3516                         "%sSyslogFacility: %s\n"
3517                         "%sSyslogLevel: %s\n",
3518                         prefix, strna(fac_str),
3519                         prefix, strna(lvl_str));
3520         }
3521
3522         if (c->secure_bits)
3523                 fprintf(f, "%sSecure Bits:%s%s%s%s%s%s\n",
3524                         prefix,
3525                         (c->secure_bits & 1<<SECURE_KEEP_CAPS) ? " keep-caps" : "",
3526                         (c->secure_bits & 1<<SECURE_KEEP_CAPS_LOCKED) ? " keep-caps-locked" : "",
3527                         (c->secure_bits & 1<<SECURE_NO_SETUID_FIXUP) ? " no-setuid-fixup" : "",
3528                         (c->secure_bits & 1<<SECURE_NO_SETUID_FIXUP_LOCKED) ? " no-setuid-fixup-locked" : "",
3529                         (c->secure_bits & 1<<SECURE_NOROOT) ? " noroot" : "",
3530                         (c->secure_bits & 1<<SECURE_NOROOT_LOCKED) ? "noroot-locked" : "");
3531
3532         if (c->capability_bounding_set != CAP_ALL) {
3533                 unsigned long l;
3534                 fprintf(f, "%sCapabilityBoundingSet:", prefix);
3535
3536                 for (l = 0; l <= cap_last_cap(); l++)
3537                         if (c->capability_bounding_set & (UINT64_C(1) << l))
3538                                 fprintf(f, " %s", strna(capability_to_name(l)));
3539
3540                 fputs("\n", f);
3541         }
3542
3543         if (c->capability_ambient_set != 0) {
3544                 unsigned long l;
3545                 fprintf(f, "%sAmbientCapabilities:", prefix);
3546
3547                 for (l = 0; l <= cap_last_cap(); l++)
3548                         if (c->capability_ambient_set & (UINT64_C(1) << l))
3549                                 fprintf(f, " %s", strna(capability_to_name(l)));
3550
3551                 fputs("\n", f);
3552         }
3553
3554         if (c->user)
3555                 fprintf(f, "%sUser: %s\n", prefix, c->user);
3556         if (c->group)
3557                 fprintf(f, "%sGroup: %s\n", prefix, c->group);
3558
3559         fprintf(f, "%sDynamicUser: %s\n", prefix, yes_no(c->dynamic_user));
3560
3561         if (strv_length(c->supplementary_groups) > 0) {
3562                 fprintf(f, "%sSupplementaryGroups:", prefix);
3563                 strv_fprintf(f, c->supplementary_groups);
3564                 fputs("\n", f);
3565         }
3566
3567         if (c->pam_name)
3568                 fprintf(f, "%sPAMName: %s\n", prefix, c->pam_name);
3569
3570         if (strv_length(c->read_write_paths) > 0) {
3571                 fprintf(f, "%sReadWritePaths:", prefix);
3572                 strv_fprintf(f, c->read_write_paths);
3573                 fputs("\n", f);
3574         }
3575
3576         if (strv_length(c->read_only_paths) > 0) {
3577                 fprintf(f, "%sReadOnlyPaths:", prefix);
3578                 strv_fprintf(f, c->read_only_paths);
3579                 fputs("\n", f);
3580         }
3581
3582         if (strv_length(c->inaccessible_paths) > 0) {
3583                 fprintf(f, "%sInaccessiblePaths:", prefix);
3584                 strv_fprintf(f, c->inaccessible_paths);
3585                 fputs("\n", f);
3586         }
3587
3588         if (c->n_bind_mounts > 0)
3589                 for (i = 0; i < c->n_bind_mounts; i++) {
3590                         fprintf(f, "%s%s: %s:%s:%s\n", prefix,
3591                                 c->bind_mounts[i].read_only ? "BindReadOnlyPaths" : "BindPaths",
3592                                 c->bind_mounts[i].source,
3593                                 c->bind_mounts[i].destination,
3594                                 c->bind_mounts[i].recursive ? "rbind" : "norbind");
3595                 }
3596
3597         if (c->utmp_id)
3598                 fprintf(f,
3599                         "%sUtmpIdentifier: %s\n",
3600                         prefix, c->utmp_id);
3601
3602         if (c->selinux_context)
3603                 fprintf(f,
3604                         "%sSELinuxContext: %s%s\n",
3605                         prefix, c->selinux_context_ignore ? "-" : "", c->selinux_context);
3606
3607         if (c->personality != PERSONALITY_INVALID)
3608                 fprintf(f,
3609                         "%sPersonality: %s\n",
3610                         prefix, strna(personality_to_string(c->personality)));
3611
3612         if (c->syscall_filter) {
3613 #ifdef HAVE_SECCOMP
3614                 Iterator j;
3615                 void *id;
3616                 bool first = true;
3617 #endif
3618
3619                 fprintf(f,
3620                         "%sSystemCallFilter: ",
3621                         prefix);
3622
3623                 if (!c->syscall_whitelist)
3624                         fputc('~', f);
3625
3626 #ifdef HAVE_SECCOMP
3627                 SET_FOREACH(id, c->syscall_filter, j) {
3628                         _cleanup_free_ char *name = NULL;
3629
3630                         if (first)
3631                                 first = false;
3632                         else
3633                                 fputc(' ', f);
3634
3635                         name = seccomp_syscall_resolve_num_arch(SCMP_ARCH_NATIVE, PTR_TO_INT(id) - 1);
3636                         fputs(strna(name), f);
3637                 }
3638 #endif
3639
3640                 fputc('\n', f);
3641         }
3642
3643         if (c->syscall_archs) {
3644 #ifdef HAVE_SECCOMP
3645                 Iterator j;
3646                 void *id;
3647 #endif
3648
3649                 fprintf(f,
3650                         "%sSystemCallArchitectures:",
3651                         prefix);
3652
3653 #ifdef HAVE_SECCOMP
3654                 SET_FOREACH(id, c->syscall_archs, j)
3655                         fprintf(f, " %s", strna(seccomp_arch_to_string(PTR_TO_UINT32(id) - 1)));
3656 #endif
3657                 fputc('\n', f);
3658         }
3659
3660         if (exec_context_restrict_namespaces_set(c)) {
3661                 _cleanup_free_ char *s = NULL;
3662
3663                 r = namespace_flag_to_string_many(c->restrict_namespaces, &s);
3664                 if (r >= 0)
3665                         fprintf(f, "%sRestrictNamespaces: %s\n",
3666                                 prefix, s);
3667         }
3668
3669         if (c->syscall_errno > 0)
3670                 fprintf(f,
3671                         "%sSystemCallErrorNumber: %s\n",
3672                         prefix, strna(errno_to_name(c->syscall_errno)));
3673
3674         if (c->apparmor_profile)
3675                 fprintf(f,
3676                         "%sAppArmorProfile: %s%s\n",
3677                         prefix, c->apparmor_profile_ignore ? "-" : "", c->apparmor_profile);
3678 }
3679
3680 bool exec_context_maintains_privileges(ExecContext *c) {
3681         assert(c);
3682
3683         /* Returns true if the process forked off would run under
3684          * an unchanged UID or as root. */
3685
3686         if (!c->user)
3687                 return true;
3688
3689         if (streq(c->user, "root") || streq(c->user, "0"))
3690                 return true;
3691
3692         return false;
3693 }
3694
3695 void exec_status_start(ExecStatus *s, pid_t pid) {
3696         assert(s);
3697
3698         zero(*s);
3699         s->pid = pid;
3700         dual_timestamp_get(&s->start_timestamp);
3701 }
3702
3703 void exec_status_exit(ExecStatus *s, ExecContext *context, pid_t pid, int code, int status) {
3704         assert(s);
3705
3706         if (s->pid && s->pid != pid)
3707                 zero(*s);
3708
3709         s->pid = pid;
3710         dual_timestamp_get(&s->exit_timestamp);
3711
3712         s->code = code;
3713         s->status = status;
3714
3715         if (context) {
3716                 if (context->utmp_id)
3717                         utmp_put_dead_process(context->utmp_id, pid, code, status);
3718
3719                 exec_context_tty_reset(context, NULL);
3720         }
3721 }
3722
3723 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix) {
3724         char buf[FORMAT_TIMESTAMP_MAX];
3725
3726         assert(s);
3727         assert(f);
3728
3729         if (s->pid <= 0)
3730                 return;
3731
3732         prefix = strempty(prefix);
3733
3734         fprintf(f,
3735                 "%sPID: "PID_FMT"\n",
3736                 prefix, s->pid);
3737
3738         if (dual_timestamp_is_set(&s->start_timestamp))
3739                 fprintf(f,
3740                         "%sStart Timestamp: %s\n",
3741                         prefix, format_timestamp(buf, sizeof(buf), s->start_timestamp.realtime));
3742
3743         if (dual_timestamp_is_set(&s->exit_timestamp))
3744                 fprintf(f,
3745                         "%sExit Timestamp: %s\n"
3746                         "%sExit Code: %s\n"
3747                         "%sExit Status: %i\n",
3748                         prefix, format_timestamp(buf, sizeof(buf), s->exit_timestamp.realtime),
3749                         prefix, sigchld_code_to_string(s->code),
3750                         prefix, s->status);
3751 }
3752
3753 char *exec_command_line(char **argv) {
3754         size_t k;
3755         char *n, *p, **a;
3756         bool first = true;
3757
3758         assert(argv);
3759
3760         k = 1;
3761         STRV_FOREACH(a, argv)
3762                 k += strlen(*a)+3;
3763
3764         n = new(char, k);
3765         if (!n)
3766                 return NULL;
3767
3768         p = n;
3769         STRV_FOREACH(a, argv) {
3770
3771                 if (!first)
3772                         *(p++) = ' ';
3773                 else
3774                         first = false;
3775
3776                 if (strpbrk(*a, WHITESPACE)) {
3777                         *(p++) = '\'';
3778                         p = stpcpy(p, *a);
3779                         *(p++) = '\'';
3780                 } else
3781                         p = stpcpy(p, *a);
3782
3783         }
3784
3785         *p = 0;
3786
3787         /* FIXME: this doesn't really handle arguments that have
3788          * spaces and ticks in them */
3789
3790         return n;
3791 }
3792
3793 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
3794         _cleanup_free_ char *cmd = NULL;
3795         const char *prefix2;
3796
3797         assert(c);
3798         assert(f);
3799
3800         prefix = strempty(prefix);
3801         prefix2 = strjoina(prefix, "\t");
3802
3803         cmd = exec_command_line(c->argv);
3804         fprintf(f,
3805                 "%sCommand Line: %s\n",
3806                 prefix, cmd ? cmd : strerror(ENOMEM));
3807
3808         exec_status_dump(&c->exec_status, f, prefix2);
3809 }
3810
3811 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {
3812         assert(f);
3813
3814         prefix = strempty(prefix);
3815
3816         LIST_FOREACH(command, c, c)
3817                 exec_command_dump(c, f, prefix);
3818 }
3819
3820 void exec_command_append_list(ExecCommand **l, ExecCommand *e) {
3821         ExecCommand *end;
3822
3823         assert(l);
3824         assert(e);
3825
3826         if (*l) {
3827                 /* It's kind of important, that we keep the order here */
3828                 LIST_FIND_TAIL(command, *l, end);
3829                 LIST_INSERT_AFTER(command, *l, end, e);
3830         } else
3831               *l = e;
3832 }
3833
3834 int exec_command_set(ExecCommand *c, const char *path, ...) {
3835         va_list ap;
3836         char **l, *p;
3837
3838         assert(c);
3839         assert(path);
3840
3841         va_start(ap, path);
3842         l = strv_new_ap(path, ap);
3843         va_end(ap);
3844
3845         if (!l)
3846                 return -ENOMEM;
3847
3848         p = strdup(path);
3849         if (!p) {
3850                 strv_free(l);
3851                 return -ENOMEM;
3852         }
3853
3854         free(c->path);
3855         c->path = p;
3856
3857         strv_free(c->argv);
3858         c->argv = l;
3859
3860         return 0;
3861 }
3862
3863 int exec_command_append(ExecCommand *c, const char *path, ...) {
3864         _cleanup_strv_free_ char **l = NULL;
3865         va_list ap;
3866         int r;
3867
3868         assert(c);
3869         assert(path);
3870
3871         va_start(ap, path);
3872         l = strv_new_ap(path, ap);
3873         va_end(ap);
3874
3875         if (!l)
3876                 return -ENOMEM;
3877
3878         r = strv_extend_strv(&c->argv, l, false);
3879         if (r < 0)
3880                 return r;
3881
3882         return 0;
3883 }
3884
3885
3886 static int exec_runtime_allocate(ExecRuntime **rt) {
3887
3888         if (*rt)
3889                 return 0;
3890
3891         *rt = new0(ExecRuntime, 1);
3892         if (!*rt)
3893                 return -ENOMEM;
3894
3895         (*rt)->n_ref = 1;
3896         (*rt)->netns_storage_socket[0] = (*rt)->netns_storage_socket[1] = -1;
3897
3898         return 0;
3899 }
3900
3901 int exec_runtime_make(ExecRuntime **rt, ExecContext *c, const char *id) {
3902         int r;
3903
3904         assert(rt);
3905         assert(c);
3906         assert(id);
3907
3908         if (*rt)
3909                 return 1;
3910
3911         if (!c->private_network && !c->private_tmp)
3912                 return 0;
3913
3914         r = exec_runtime_allocate(rt);
3915         if (r < 0)
3916                 return r;
3917
3918         if (c->private_network && (*rt)->netns_storage_socket[0] < 0) {
3919                 if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0, (*rt)->netns_storage_socket) < 0)
3920                         return -errno;
3921         }
3922
3923         if (c->private_tmp && !(*rt)->tmp_dir) {
3924                 r = setup_tmp_dirs(id, &(*rt)->tmp_dir, &(*rt)->var_tmp_dir);
3925                 if (r < 0)
3926                         return r;
3927         }
3928
3929         return 1;
3930 }
3931
3932 ExecRuntime *exec_runtime_ref(ExecRuntime *r) {
3933         assert(r);
3934         assert(r->n_ref > 0);
3935
3936         r->n_ref++;
3937         return r;
3938 }
3939
3940 ExecRuntime *exec_runtime_unref(ExecRuntime *r) {
3941
3942         if (!r)
3943                 return NULL;
3944
3945         assert(r->n_ref > 0);
3946
3947         r->n_ref--;
3948         if (r->n_ref > 0)
3949                 return NULL;
3950
3951         free(r->tmp_dir);
3952         free(r->var_tmp_dir);
3953         safe_close_pair(r->netns_storage_socket);
3954         return mfree(r);
3955 }
3956
3957 int exec_runtime_serialize(Unit *u, ExecRuntime *rt, FILE *f, FDSet *fds) {
3958         assert(u);
3959         assert(f);
3960         assert(fds);
3961
3962         if (!rt)
3963                 return 0;
3964
3965         if (rt->tmp_dir)
3966                 unit_serialize_item(u, f, "tmp-dir", rt->tmp_dir);
3967
3968         if (rt->var_tmp_dir)
3969                 unit_serialize_item(u, f, "var-tmp-dir", rt->var_tmp_dir);
3970
3971         if (rt->netns_storage_socket[0] >= 0) {
3972                 int copy;
3973
3974                 copy = fdset_put_dup(fds, rt->netns_storage_socket[0]);
3975                 if (copy < 0)
3976                         return copy;
3977
3978                 unit_serialize_item_format(u, f, "netns-socket-0", "%i", copy);
3979         }
3980
3981         if (rt->netns_storage_socket[1] >= 0) {
3982                 int copy;
3983
3984                 copy = fdset_put_dup(fds, rt->netns_storage_socket[1]);
3985                 if (copy < 0)
3986                         return copy;
3987
3988                 unit_serialize_item_format(u, f, "netns-socket-1", "%i", copy);
3989         }
3990
3991         return 0;
3992 }
3993
3994 int exec_runtime_deserialize_item(Unit *u, ExecRuntime **rt, const char *key, const char *value, FDSet *fds) {
3995         int r;
3996
3997         assert(rt);
3998         assert(key);
3999         assert(value);
4000
4001         if (streq(key, "tmp-dir")) {
4002                 char *copy;
4003
4004                 r = exec_runtime_allocate(rt);
4005                 if (r < 0)
4006                         return log_oom();
4007
4008                 copy = strdup(value);
4009                 if (!copy)
4010                         return log_oom();
4011
4012                 free((*rt)->tmp_dir);
4013                 (*rt)->tmp_dir = copy;
4014
4015         } else if (streq(key, "var-tmp-dir")) {
4016                 char *copy;
4017
4018                 r = exec_runtime_allocate(rt);
4019                 if (r < 0)
4020                         return log_oom();
4021
4022                 copy = strdup(value);
4023                 if (!copy)
4024                         return log_oom();
4025
4026                 free((*rt)->var_tmp_dir);
4027                 (*rt)->var_tmp_dir = copy;
4028
4029         } else if (streq(key, "netns-socket-0")) {
4030                 int fd;
4031
4032                 r = exec_runtime_allocate(rt);
4033                 if (r < 0)
4034                         return log_oom();
4035
4036                 if (safe_atoi(value, &fd) < 0 || !fdset_contains(fds, fd))
4037                         log_unit_debug(u, "Failed to parse netns socket value: %s", value);
4038                 else {
4039                         safe_close((*rt)->netns_storage_socket[0]);
4040                         (*rt)->netns_storage_socket[0] = fdset_remove(fds, fd);
4041                 }
4042         } else if (streq(key, "netns-socket-1")) {
4043                 int fd;
4044
4045                 r = exec_runtime_allocate(rt);
4046                 if (r < 0)
4047                         return log_oom();
4048
4049                 if (safe_atoi(value, &fd) < 0 || !fdset_contains(fds, fd))
4050                         log_unit_debug(u, "Failed to parse netns socket value: %s", value);
4051                 else {
4052                         safe_close((*rt)->netns_storage_socket[1]);
4053                         (*rt)->netns_storage_socket[1] = fdset_remove(fds, fd);
4054                 }
4055         } else
4056                 return 0;
4057
4058         return 1;
4059 }
4060
4061 static void *remove_tmpdir_thread(void *p) {
4062         _cleanup_free_ char *path = p;
4063
4064         (void) rm_rf(path, REMOVE_ROOT|REMOVE_PHYSICAL);
4065         return NULL;
4066 }
4067
4068 void exec_runtime_destroy(ExecRuntime *rt) {
4069         int r;
4070
4071         if (!rt)
4072                 return;
4073
4074         /* If there are multiple users of this, let's leave the stuff around */
4075         if (rt->n_ref > 1)
4076                 return;
4077
4078         if (rt->tmp_dir) {
4079                 log_debug("Spawning thread to nuke %s", rt->tmp_dir);
4080
4081                 r = asynchronous_job(remove_tmpdir_thread, rt->tmp_dir);
4082                 if (r < 0) {
4083                         log_warning_errno(r, "Failed to nuke %s: %m", rt->tmp_dir);
4084                         free(rt->tmp_dir);
4085                 }
4086
4087                 rt->tmp_dir = NULL;
4088         }
4089
4090         if (rt->var_tmp_dir) {
4091                 log_debug("Spawning thread to nuke %s", rt->var_tmp_dir);
4092
4093                 r = asynchronous_job(remove_tmpdir_thread, rt->var_tmp_dir);
4094                 if (r < 0) {
4095                         log_warning_errno(r, "Failed to nuke %s: %m", rt->var_tmp_dir);
4096                         free(rt->var_tmp_dir);
4097                 }
4098
4099                 rt->var_tmp_dir = NULL;
4100         }
4101
4102         safe_close_pair(rt->netns_storage_socket);
4103 }
4104
4105 static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
4106         [EXEC_INPUT_NULL] = "null",
4107         [EXEC_INPUT_TTY] = "tty",
4108         [EXEC_INPUT_TTY_FORCE] = "tty-force",
4109         [EXEC_INPUT_TTY_FAIL] = "tty-fail",
4110         [EXEC_INPUT_SOCKET] = "socket",
4111         [EXEC_INPUT_NAMED_FD] = "fd",
4112 };
4113
4114 DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput);
4115
4116 static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
4117         [EXEC_OUTPUT_INHERIT] = "inherit",
4118         [EXEC_OUTPUT_NULL] = "null",
4119         [EXEC_OUTPUT_TTY] = "tty",
4120         [EXEC_OUTPUT_SYSLOG] = "syslog",
4121         [EXEC_OUTPUT_SYSLOG_AND_CONSOLE] = "syslog+console",
4122         [EXEC_OUTPUT_KMSG] = "kmsg",
4123         [EXEC_OUTPUT_KMSG_AND_CONSOLE] = "kmsg+console",
4124         [EXEC_OUTPUT_JOURNAL] = "journal",
4125         [EXEC_OUTPUT_JOURNAL_AND_CONSOLE] = "journal+console",
4126         [EXEC_OUTPUT_SOCKET] = "socket",
4127         [EXEC_OUTPUT_NAMED_FD] = "fd",
4128 };
4129
4130 DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);
4131
4132 static const char* const exec_utmp_mode_table[_EXEC_UTMP_MODE_MAX] = {
4133         [EXEC_UTMP_INIT] = "init",
4134         [EXEC_UTMP_LOGIN] = "login",
4135         [EXEC_UTMP_USER] = "user",
4136 };
4137
4138 DEFINE_STRING_TABLE_LOOKUP(exec_utmp_mode, ExecUtmpMode);