1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2010 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
29 #include <sys/socket.h>
31 #include <sys/prctl.h>
32 #include <linux/sched.h>
33 #include <sys/types.h>
37 #include <sys/mount.h>
39 #include <linux/oom.h>
43 #include <security/pam_appl.h>
49 #include "capability.h"
53 #include "securebits.h"
55 #include "namespace.h"
57 #include "exit-status.h"
59 #include "utmp-wtmp.h"
61 #include "loopback-setup.h"
62 #include "path-util.h"
64 #define IDLE_TIMEOUT_USEC (5*USEC_PER_SEC)
66 /* This assumes there is a 'tty' group */
69 static int shift_fds(int fds[], unsigned n_fds) {
70 int start, restart_from;
75 /* Modifies the fds array! (sorts it) */
85 for (i = start; i < (int) n_fds; i++) {
88 /* Already at right index? */
92 if ((nfd = fcntl(fds[i], F_DUPFD, i+3)) < 0)
95 close_nointr_nofail(fds[i]);
98 /* Hmm, the fd we wanted isn't free? Then
99 * let's remember that and try again from here*/
100 if (nfd != i+3 && restart_from < 0)
104 if (restart_from < 0)
107 start = restart_from;
113 static int flags_fds(const int fds[], unsigned n_fds, bool nonblock) {
122 /* Drops/Sets O_NONBLOCK and FD_CLOEXEC from the file flags */
124 for (i = 0; i < n_fds; i++) {
126 if ((r = fd_nonblock(fds[i], nonblock)) < 0)
129 /* We unconditionally drop FD_CLOEXEC from the fds,
130 * since after all we want to pass these fds to our
133 if ((r = fd_cloexec(fds[i], false)) < 0)
140 static const char *tty_path(const ExecContext *context) {
143 if (context->tty_path)
144 return context->tty_path;
146 return "/dev/console";
149 void exec_context_tty_reset(const ExecContext *context) {
152 if (context->tty_vhangup)
153 terminal_vhangup(tty_path(context));
155 if (context->tty_reset)
156 reset_terminal(tty_path(context));
158 if (context->tty_vt_disallocate && context->tty_path)
159 vt_disallocate(context->tty_path);
162 static int open_null_as(int flags, int nfd) {
167 if ((fd = open("/dev/null", flags|O_NOCTTY)) < 0)
171 r = dup2(fd, nfd) < 0 ? -errno : nfd;
172 close_nointr_nofail(fd);
179 static int connect_logger_as(const ExecContext *context, ExecOutput output, const char *ident, int nfd) {
181 union sockaddr_union sa;
184 assert(output < _EXEC_OUTPUT_MAX);
188 fd = socket(AF_UNIX, SOCK_STREAM, 0);
193 sa.un.sun_family = AF_UNIX;
194 strncpy(sa.un.sun_path, "/run/systemd/journal/stdout", sizeof(sa.un.sun_path));
196 r = connect(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path));
198 close_nointr_nofail(fd);
202 if (shutdown(fd, SHUT_RD) < 0) {
203 close_nointr_nofail(fd);
214 context->syslog_identifier ? context->syslog_identifier : ident,
215 context->syslog_priority,
216 !!context->syslog_level_prefix,
217 output == EXEC_OUTPUT_SYSLOG || output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE,
218 output == EXEC_OUTPUT_KMSG || output == EXEC_OUTPUT_KMSG_AND_CONSOLE,
219 output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || output == EXEC_OUTPUT_KMSG_AND_CONSOLE || output == EXEC_OUTPUT_JOURNAL_AND_CONSOLE);
222 r = dup2(fd, nfd) < 0 ? -errno : nfd;
223 close_nointr_nofail(fd);
229 static int open_terminal_as(const char *path, mode_t mode, int nfd) {
235 if ((fd = open_terminal(path, mode | O_NOCTTY)) < 0)
239 r = dup2(fd, nfd) < 0 ? -errno : nfd;
240 close_nointr_nofail(fd);
247 static bool is_terminal_input(ExecInput i) {
249 i == EXEC_INPUT_TTY ||
250 i == EXEC_INPUT_TTY_FORCE ||
251 i == EXEC_INPUT_TTY_FAIL;
254 static int fixup_input(ExecInput std_input, int socket_fd, bool apply_tty_stdin) {
256 if (is_terminal_input(std_input) && !apply_tty_stdin)
257 return EXEC_INPUT_NULL;
259 if (std_input == EXEC_INPUT_SOCKET && socket_fd < 0)
260 return EXEC_INPUT_NULL;
265 static int fixup_output(ExecOutput std_output, int socket_fd) {
267 if (std_output == EXEC_OUTPUT_SOCKET && socket_fd < 0)
268 return EXEC_OUTPUT_INHERIT;
273 static int setup_input(const ExecContext *context, int socket_fd, bool apply_tty_stdin) {
278 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
282 case EXEC_INPUT_NULL:
283 return open_null_as(O_RDONLY, STDIN_FILENO);
286 case EXEC_INPUT_TTY_FORCE:
287 case EXEC_INPUT_TTY_FAIL: {
290 if ((fd = acquire_terminal(
292 i == EXEC_INPUT_TTY_FAIL,
293 i == EXEC_INPUT_TTY_FORCE,
297 if (fd != STDIN_FILENO) {
298 r = dup2(fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
299 close_nointr_nofail(fd);
306 case EXEC_INPUT_SOCKET:
307 return dup2(socket_fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
310 assert_not_reached("Unknown input type");
314 static int setup_output(const ExecContext *context, int socket_fd, const char *ident, bool apply_tty_stdin) {
321 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
322 o = fixup_output(context->std_output, socket_fd);
324 /* This expects the input is already set up */
328 case EXEC_OUTPUT_INHERIT:
330 /* If input got downgraded, inherit the original value */
331 if (i == EXEC_INPUT_NULL && is_terminal_input(context->std_input))
332 return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
334 /* If the input is connected to anything that's not a /dev/null, inherit that... */
335 if (i != EXEC_INPUT_NULL)
336 return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
338 /* If we are not started from PID 1 we just inherit STDOUT from our parent process. */
340 return STDOUT_FILENO;
342 /* We need to open /dev/null here anew, to get the
343 * right access mode. So we fall through */
345 case EXEC_OUTPUT_NULL:
346 return open_null_as(O_WRONLY, STDOUT_FILENO);
348 case EXEC_OUTPUT_TTY:
349 if (is_terminal_input(i))
350 return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
352 /* We don't reset the terminal if this is just about output */
353 return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
355 case EXEC_OUTPUT_SYSLOG:
356 case EXEC_OUTPUT_SYSLOG_AND_CONSOLE:
357 case EXEC_OUTPUT_KMSG:
358 case EXEC_OUTPUT_KMSG_AND_CONSOLE:
359 case EXEC_OUTPUT_JOURNAL:
360 case EXEC_OUTPUT_JOURNAL_AND_CONSOLE:
361 return connect_logger_as(context, o, ident, STDOUT_FILENO);
363 case EXEC_OUTPUT_SOCKET:
364 assert(socket_fd >= 0);
365 return dup2(socket_fd, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
368 assert_not_reached("Unknown output type");
372 static int setup_error(const ExecContext *context, int socket_fd, const char *ident, bool apply_tty_stdin) {
379 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
380 o = fixup_output(context->std_output, socket_fd);
381 e = fixup_output(context->std_error, socket_fd);
383 /* This expects the input and output are already set up */
385 /* Don't change the stderr file descriptor if we inherit all
386 * the way and are not on a tty */
387 if (e == EXEC_OUTPUT_INHERIT &&
388 o == EXEC_OUTPUT_INHERIT &&
389 i == EXEC_INPUT_NULL &&
390 !is_terminal_input(context->std_input) &&
392 return STDERR_FILENO;
394 /* Duplicate from stdout if possible */
395 if (e == o || e == EXEC_OUTPUT_INHERIT)
396 return dup2(STDOUT_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
400 case EXEC_OUTPUT_NULL:
401 return open_null_as(O_WRONLY, STDERR_FILENO);
403 case EXEC_OUTPUT_TTY:
404 if (is_terminal_input(i))
405 return dup2(STDIN_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
407 /* We don't reset the terminal if this is just about output */
408 return open_terminal_as(tty_path(context), O_WRONLY, STDERR_FILENO);
410 case EXEC_OUTPUT_SYSLOG:
411 case EXEC_OUTPUT_SYSLOG_AND_CONSOLE:
412 case EXEC_OUTPUT_KMSG:
413 case EXEC_OUTPUT_KMSG_AND_CONSOLE:
414 case EXEC_OUTPUT_JOURNAL:
415 case EXEC_OUTPUT_JOURNAL_AND_CONSOLE:
416 return connect_logger_as(context, e, ident, STDERR_FILENO);
418 case EXEC_OUTPUT_SOCKET:
419 assert(socket_fd >= 0);
420 return dup2(socket_fd, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
423 assert_not_reached("Unknown error type");
427 static int chown_terminal(int fd, uid_t uid) {
432 /* This might fail. What matters are the results. */
433 (void) fchown(fd, uid, -1);
434 (void) fchmod(fd, TTY_MODE);
436 if (fstat(fd, &st) < 0)
439 if (st.st_uid != uid || (st.st_mode & 0777) != TTY_MODE)
445 static int setup_confirm_stdio(const ExecContext *context,
447 int *_saved_stdout) {
448 int fd = -1, saved_stdin, saved_stdout = -1, r;
451 assert(_saved_stdin);
452 assert(_saved_stdout);
454 /* This returns positive EXIT_xxx return values instead of
455 * negative errno style values! */
457 if ((saved_stdin = fcntl(STDIN_FILENO, F_DUPFD, 3)) < 0)
460 if ((saved_stdout = fcntl(STDOUT_FILENO, F_DUPFD, 3)) < 0) {
465 if ((fd = acquire_terminal(
467 context->std_input == EXEC_INPUT_TTY_FAIL,
468 context->std_input == EXEC_INPUT_TTY_FORCE,
474 if (chown_terminal(fd, getuid()) < 0) {
479 if (dup2(fd, STDIN_FILENO) < 0) {
484 if (dup2(fd, STDOUT_FILENO) < 0) {
490 close_nointr_nofail(fd);
492 *_saved_stdin = saved_stdin;
493 *_saved_stdout = saved_stdout;
498 if (saved_stdout >= 0)
499 close_nointr_nofail(saved_stdout);
501 if (saved_stdin >= 0)
502 close_nointr_nofail(saved_stdin);
505 close_nointr_nofail(fd);
510 static int restore_confirm_stdio(const ExecContext *context,
518 assert(*saved_stdin >= 0);
519 assert(saved_stdout);
520 assert(*saved_stdout >= 0);
522 /* This returns positive EXIT_xxx return values instead of
523 * negative errno style values! */
525 if (is_terminal_input(context->std_input)) {
527 /* The service wants terminal input. */
531 context->std_output == EXEC_OUTPUT_INHERIT ||
532 context->std_output == EXEC_OUTPUT_TTY;
535 /* If the service doesn't want a controlling terminal,
536 * then we need to get rid entirely of what we have
539 if (release_terminal() < 0)
542 if (dup2(*saved_stdin, STDIN_FILENO) < 0)
545 if (dup2(*saved_stdout, STDOUT_FILENO) < 0)
548 *keep_stdout = *keep_stdin = false;
554 static int enforce_groups(const ExecContext *context, const char *username, gid_t gid) {
555 bool keep_groups = false;
560 /* Lookup and set GID and supplementary group list. Here too
561 * we avoid NSS lookups for gid=0. */
563 if (context->group || username) {
565 if (context->group) {
566 const char *g = context->group;
568 if ((r = get_group_creds(&g, &gid)) < 0)
572 /* First step, initialize groups from /etc/groups */
573 if (username && gid != 0) {
574 if (initgroups(username, gid) < 0)
580 /* Second step, set our gids */
581 if (setresgid(gid, gid, gid) < 0)
585 if (context->supplementary_groups) {
590 /* Final step, initialize any manually set supplementary groups */
591 assert_se((ngroups_max = (int) sysconf(_SC_NGROUPS_MAX)) > 0);
593 if (!(gids = new(gid_t, ngroups_max)))
597 if ((k = getgroups(ngroups_max, gids)) < 0) {
604 STRV_FOREACH(i, context->supplementary_groups) {
607 if (k >= ngroups_max) {
613 r = get_group_creds(&g, gids+k);
622 if (setgroups(k, gids) < 0) {
633 static int enforce_user(const ExecContext *context, uid_t uid) {
637 /* Sets (but doesn't lookup) the uid and make sure we keep the
638 * capabilities while doing so. */
640 if (context->capabilities) {
642 static const cap_value_t bits[] = {
643 CAP_SETUID, /* Necessary so that we can run setresuid() below */
644 CAP_SETPCAP /* Necessary so that we can set PR_SET_SECUREBITS later on */
647 /* First step: If we need to keep capabilities but
648 * drop privileges we need to make sure we keep our
649 * caps, whiel we drop privileges. */
651 int sb = context->secure_bits|SECURE_KEEP_CAPS;
653 if (prctl(PR_GET_SECUREBITS) != sb)
654 if (prctl(PR_SET_SECUREBITS, sb) < 0)
658 /* Second step: set the capabilities. This will reduce
659 * the capabilities to the minimum we need. */
661 if (!(d = cap_dup(context->capabilities)))
664 if (cap_set_flag(d, CAP_EFFECTIVE, ELEMENTSOF(bits), bits, CAP_SET) < 0 ||
665 cap_set_flag(d, CAP_PERMITTED, ELEMENTSOF(bits), bits, CAP_SET) < 0) {
671 if (cap_set_proc(d) < 0) {
680 /* Third step: actually set the uids */
681 if (setresuid(uid, uid, uid) < 0)
684 /* At this point we should have all necessary capabilities but
685 are otherwise a normal user. However, the caps might got
686 corrupted due to the setresuid() so we need clean them up
687 later. This is done outside of this call. */
694 static int null_conv(
696 const struct pam_message **msg,
697 struct pam_response **resp,
700 /* We don't support conversations */
705 static int setup_pam(
711 int fds[], unsigned n_fds) {
713 static const struct pam_conv conv = {
718 pam_handle_t *handle = NULL;
720 int pam_code = PAM_SUCCESS;
723 bool close_session = false;
724 pid_t pam_pid = 0, parent_pid;
730 /* We set up PAM in the parent process, then fork. The child
731 * will then stay around until killed via PR_GET_PDEATHSIG or
732 * systemd via the cgroup logic. It will then remove the PAM
733 * session again. The parent process will exec() the actual
734 * daemon. We do things this way to ensure that the main PID
735 * of the daemon is the one we initially fork()ed. */
737 if ((pam_code = pam_start(name, user, &conv, &handle)) != PAM_SUCCESS) {
743 if ((pam_code = pam_set_item(handle, PAM_TTY, tty)) != PAM_SUCCESS)
746 if ((pam_code = pam_acct_mgmt(handle, PAM_SILENT)) != PAM_SUCCESS)
749 if ((pam_code = pam_open_session(handle, PAM_SILENT)) != PAM_SUCCESS)
752 close_session = true;
754 if ((!(e = pam_getenvlist(handle)))) {
755 pam_code = PAM_BUF_ERR;
759 /* Block SIGTERM, so that we know that it won't get lost in
761 if (sigemptyset(&ss) < 0 ||
762 sigaddset(&ss, SIGTERM) < 0 ||
763 sigprocmask(SIG_BLOCK, &ss, &old_ss) < 0)
766 parent_pid = getpid();
768 if ((pam_pid = fork()) < 0)
775 /* The child's job is to reset the PAM session on
778 /* This string must fit in 10 chars (i.e. the length
779 * of "/sbin/init"), to look pretty in /bin/ps */
780 rename_process("(sd-pam)");
782 /* Make sure we don't keep open the passed fds in this
783 child. We assume that otherwise only those fds are
784 open here that have been opened by PAM. */
785 close_many(fds, n_fds);
787 /* Drop privileges - we don't need any to pam_close_session
788 * and this will make PR_SET_PDEATHSIG work in most cases.
789 * If this fails, ignore the error - but expect sd-pam threads
790 * to fail to exit normally */
791 if (setresuid(uid, uid, uid) < 0)
792 log_error("Error: Failed to setresuid() in sd-pam: %s", strerror(-r));
794 /* Wait until our parent died. This will only work if
795 * the above setresuid() succeeds, otherwise the kernel
796 * will not allow unprivileged parents kill their privileged
797 * children this way. We rely on the control groups kill logic
798 * to do the rest for us. */
799 if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
802 /* Check if our parent process might already have
804 if (getppid() == parent_pid) {
806 if (sigwait(&ss, &sig) < 0) {
813 assert(sig == SIGTERM);
818 /* If our parent died we'll end the session */
819 if (getppid() != parent_pid)
820 if ((pam_code = pam_close_session(handle, PAM_DATA_SILENT)) != PAM_SUCCESS)
826 pam_end(handle, pam_code | PAM_DATA_SILENT);
830 /* If the child was forked off successfully it will do all the
831 * cleanups, so forget about the handle here. */
834 /* Unblock SIGTERM again in the parent */
835 if (sigprocmask(SIG_SETMASK, &old_ss, NULL) < 0)
838 /* We close the log explicitly here, since the PAM modules
839 * might have opened it, but we don't want this fd around. */
848 if (pam_code != PAM_SUCCESS)
849 err = -EPERM; /* PAM errors do not map to errno */
855 pam_code = pam_close_session(handle, PAM_DATA_SILENT);
857 pam_end(handle, pam_code | PAM_DATA_SILENT);
865 kill(pam_pid, SIGTERM);
866 kill(pam_pid, SIGCONT);
873 static void rename_process_from_path(const char *path) {
874 char process_name[11];
878 /* This resulting string must fit in 10 chars (i.e. the length
879 * of "/sbin/init") to look pretty in /bin/ps */
881 p = path_get_file_name(path);
883 rename_process("(...)");
889 /* The end of the process name is usually more
890 * interesting, since the first bit might just be
896 process_name[0] = '(';
897 memcpy(process_name+1, p, l);
898 process_name[1+l] = ')';
899 process_name[1+l+1] = 0;
901 rename_process(process_name);
904 int exec_spawn(ExecCommand *command,
906 const ExecContext *context,
907 int fds[], unsigned n_fds,
909 bool apply_permissions,
911 bool apply_tty_stdin,
913 CGroupBonding *cgroup_bondings,
914 CGroupAttribute *cgroup_attributes,
915 const char *cgroup_suffix,
923 char **files_env = NULL;
928 assert(fds || n_fds <= 0);
930 if (context->std_input == EXEC_INPUT_SOCKET ||
931 context->std_output == EXEC_OUTPUT_SOCKET ||
932 context->std_error == EXEC_OUTPUT_SOCKET) {
944 if ((r = exec_context_load_environment(context, &files_env)) < 0) {
945 log_error("Failed to load environment files: %s", strerror(-r));
950 argv = command->argv;
952 if (!(line = exec_command_line(argv))) {
957 log_debug("About to execute: %s", line);
960 r = cgroup_bonding_realize_list(cgroup_bondings);
964 cgroup_attribute_apply_list(cgroup_attributes, cgroup_bondings);
966 if ((pid = fork()) < 0) {
974 const char *username = NULL, *home = NULL;
975 uid_t uid = (uid_t) -1;
976 gid_t gid = (gid_t) -1;
977 char **our_env = NULL, **pam_env = NULL, **final_env = NULL, **final_argv = NULL;
979 int saved_stdout = -1, saved_stdin = -1;
980 bool keep_stdout = false, keep_stdin = false, set_access = false;
984 rename_process_from_path(command->path);
986 /* We reset exactly these signals, since they are the
987 * only ones we set to SIG_IGN in the main daemon. All
988 * others we leave untouched because we set them to
989 * SIG_DFL or a valid handler initially, both of which
990 * will be demoted to SIG_DFL. */
991 default_signals(SIGNALS_CRASH_HANDLER,
994 if (context->ignore_sigpipe)
995 ignore_signals(SIGPIPE, -1);
997 assert_se(sigemptyset(&ss) == 0);
998 if (sigprocmask(SIG_SETMASK, &ss, NULL) < 0) {
1000 r = EXIT_SIGNAL_MASK;
1005 if (idle_pipe[1] >= 0)
1006 close_nointr_nofail(idle_pipe[1]);
1007 if (idle_pipe[0] >= 0) {
1008 fd_wait_for_event(idle_pipe[0], POLLHUP, IDLE_TIMEOUT_USEC);
1009 close_nointr_nofail(idle_pipe[0]);
1013 /* Close sockets very early to make sure we don't
1014 * block init reexecution because it cannot bind its
1017 err = close_all_fds(socket_fd >= 0 ? &socket_fd : fds,
1018 socket_fd >= 0 ? 1 : n_fds);
1024 if (!context->same_pgrp)
1031 if (context->tcpwrap_name) {
1033 if (!socket_tcpwrap(socket_fd, context->tcpwrap_name)) {
1039 for (i = 0; i < (int) n_fds; i++) {
1040 if (!socket_tcpwrap(fds[i], context->tcpwrap_name)) {
1048 exec_context_tty_reset(context);
1050 /* We skip the confirmation step if we shall not apply the TTY */
1051 if (confirm_spawn &&
1052 (!is_terminal_input(context->std_input) || apply_tty_stdin)) {
1055 /* Set up terminal for the question */
1056 if ((r = setup_confirm_stdio(context,
1057 &saved_stdin, &saved_stdout))) {
1062 /* Now ask the question. */
1063 if (!(line = exec_command_line(argv))) {
1069 r = ask(&response, "yns", "Execute %s? [Yes, No, Skip] ", line);
1072 if (r < 0 || response == 'n') {
1076 } else if (response == 's') {
1081 /* Release terminal for the question */
1082 if ((r = restore_confirm_stdio(context,
1083 &saved_stdin, &saved_stdout,
1084 &keep_stdin, &keep_stdout))) {
1090 /* If a socket is connected to STDIN/STDOUT/STDERR, we
1091 * must sure to drop O_NONBLOCK */
1093 fd_nonblock(socket_fd, false);
1096 err = setup_input(context, socket_fd, apply_tty_stdin);
1104 err = setup_output(context, socket_fd, path_get_file_name(command->path), apply_tty_stdin);
1111 err = setup_error(context, socket_fd, path_get_file_name(command->path), apply_tty_stdin);
1117 if (cgroup_bondings) {
1118 err = cgroup_bonding_install_list(cgroup_bondings, 0, cgroup_suffix);
1125 if (context->oom_score_adjust_set) {
1128 snprintf(t, sizeof(t), "%i", context->oom_score_adjust);
1131 if (write_one_line_file("/proc/self/oom_score_adj", t) < 0) {
1133 r = EXIT_OOM_ADJUST;
1138 if (context->nice_set)
1139 if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
1145 if (context->cpu_sched_set) {
1146 struct sched_param param;
1149 param.sched_priority = context->cpu_sched_priority;
1151 if (sched_setscheduler(0, context->cpu_sched_policy |
1152 (context->cpu_sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0), ¶m) < 0) {
1154 r = EXIT_SETSCHEDULER;
1159 if (context->cpuset)
1160 if (sched_setaffinity(0, CPU_ALLOC_SIZE(context->cpuset_ncpus), context->cpuset) < 0) {
1162 r = EXIT_CPUAFFINITY;
1166 if (context->ioprio_set)
1167 if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
1173 if (context->timer_slack_nsec != (nsec_t) -1)
1174 if (prctl(PR_SET_TIMERSLACK, context->timer_slack_nsec) < 0) {
1176 r = EXIT_TIMERSLACK;
1180 if (context->utmp_id)
1181 utmp_put_init_process(context->utmp_id, getpid(), getsid(0), context->tty_path);
1183 if (context->user) {
1184 username = context->user;
1185 err = get_user_creds(&username, &uid, &gid, &home);
1191 if (is_terminal_input(context->std_input)) {
1192 err = chown_terminal(STDIN_FILENO, uid);
1199 if (cgroup_bondings && context->control_group_modify) {
1200 err = cgroup_bonding_set_group_access_list(cgroup_bondings, 0755, uid, gid);
1202 err = cgroup_bonding_set_task_access_list(cgroup_bondings, 0644, uid, gid, context->control_group_persistent);
1212 if (cgroup_bondings && !set_access && context->control_group_persistent >= 0) {
1213 err = cgroup_bonding_set_task_access_list(cgroup_bondings, (mode_t) -1, (uid_t) -1, (uid_t) -1, context->control_group_persistent);
1220 if (apply_permissions) {
1221 err = enforce_groups(context, username, gid);
1228 umask(context->umask);
1231 if (context->pam_name && username) {
1232 err = setup_pam(context->pam_name, username, uid, context->tty_path, &pam_env, fds, n_fds);
1239 if (context->private_network) {
1240 if (unshare(CLONE_NEWNET) < 0) {
1249 if (strv_length(context->read_write_dirs) > 0 ||
1250 strv_length(context->read_only_dirs) > 0 ||
1251 strv_length(context->inaccessible_dirs) > 0 ||
1252 context->mount_flags != MS_SHARED ||
1253 context->private_tmp) {
1254 err = setup_namespace(context->read_write_dirs,
1255 context->read_only_dirs,
1256 context->inaccessible_dirs,
1257 context->private_tmp,
1258 context->mount_flags);
1266 if (context->root_directory)
1267 if (chroot(context->root_directory) < 0) {
1273 if (chdir(context->working_directory ? context->working_directory : "/") < 0) {
1282 if (asprintf(&d, "%s/%s",
1283 context->root_directory ? context->root_directory : "",
1284 context->working_directory ? context->working_directory : "") < 0) {
1300 /* We repeat the fd closing here, to make sure that
1301 * nothing is leaked from the PAM modules */
1302 err = close_all_fds(fds, n_fds);
1304 err = shift_fds(fds, n_fds);
1306 err = flags_fds(fds, n_fds, context->non_blocking);
1312 if (apply_permissions) {
1314 for (i = 0; i < RLIMIT_NLIMITS; i++) {
1315 if (!context->rlimit[i])
1318 if (setrlimit_closest(i, context->rlimit[i]) < 0) {
1325 if (context->capability_bounding_set_drop) {
1326 err = capability_bounding_set_drop(context->capability_bounding_set_drop, false);
1328 r = EXIT_CAPABILITIES;
1333 if (context->user) {
1334 err = enforce_user(context, uid);
1341 /* PR_GET_SECUREBITS is not privileged, while
1342 * PR_SET_SECUREBITS is. So to suppress
1343 * potential EPERMs we'll try not to call
1344 * PR_SET_SECUREBITS unless necessary. */
1345 if (prctl(PR_GET_SECUREBITS) != context->secure_bits)
1346 if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {
1348 r = EXIT_SECUREBITS;
1352 if (context->capabilities)
1353 if (cap_set_proc(context->capabilities) < 0) {
1355 r = EXIT_CAPABILITIES;
1360 if (!(our_env = new0(char*, 7))) {
1367 if (asprintf(our_env + n_env++, "LISTEN_PID=%lu", (unsigned long) getpid()) < 0 ||
1368 asprintf(our_env + n_env++, "LISTEN_FDS=%u", n_fds) < 0) {
1375 if (asprintf(our_env + n_env++, "HOME=%s", home) < 0) {
1382 if (asprintf(our_env + n_env++, "LOGNAME=%s", username) < 0 ||
1383 asprintf(our_env + n_env++, "USER=%s", username) < 0) {
1389 if (is_terminal_input(context->std_input) ||
1390 context->std_output == EXEC_OUTPUT_TTY ||
1391 context->std_error == EXEC_OUTPUT_TTY)
1392 if (!(our_env[n_env++] = strdup(default_term_for_tty(tty_path(context))))) {
1400 if (!(final_env = strv_env_merge(
1404 context->environment,
1413 if (!(final_argv = replace_env_argv(argv, final_env))) {
1419 final_env = strv_env_clean(final_env);
1421 execve(command->path, final_argv, final_env);
1428 log_warning("Failed at step %s spawning %s: %s",
1429 exit_status_to_string(r, EXIT_STATUS_SYSTEMD),
1430 command->path, strerror(-err));
1434 strv_free(final_env);
1436 strv_free(files_env);
1437 strv_free(final_argv);
1439 if (saved_stdin >= 0)
1440 close_nointr_nofail(saved_stdin);
1442 if (saved_stdout >= 0)
1443 close_nointr_nofail(saved_stdout);
1448 strv_free(files_env);
1450 /* We add the new process to the cgroup both in the child (so
1451 * that we can be sure that no user code is ever executed
1452 * outside of the cgroup) and in the parent (so that we can be
1453 * sure that when we kill the cgroup the process will be
1455 if (cgroup_bondings)
1456 cgroup_bonding_install_list(cgroup_bondings, pid, cgroup_suffix);
1458 log_debug("Forked %s as %lu", command->path, (unsigned long) pid);
1460 exec_status_start(&command->exec_status, pid);
1466 strv_free(files_env);
1471 void exec_context_init(ExecContext *c) {
1475 c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
1476 c->cpu_sched_policy = SCHED_OTHER;
1477 c->syslog_priority = LOG_DAEMON|LOG_INFO;
1478 c->syslog_level_prefix = true;
1479 c->mount_flags = MS_SHARED;
1480 c->kill_signal = SIGTERM;
1481 c->send_sigkill = true;
1482 c->control_group_persistent = -1;
1483 c->ignore_sigpipe = true;
1484 c->timer_slack_nsec = (nsec_t) -1;
1487 void exec_context_done(ExecContext *c) {
1492 strv_free(c->environment);
1493 c->environment = NULL;
1495 strv_free(c->environment_files);
1496 c->environment_files = NULL;
1498 for (l = 0; l < ELEMENTSOF(c->rlimit); l++) {
1500 c->rlimit[l] = NULL;
1503 free(c->working_directory);
1504 c->working_directory = NULL;
1505 free(c->root_directory);
1506 c->root_directory = NULL;
1511 free(c->tcpwrap_name);
1512 c->tcpwrap_name = NULL;
1514 free(c->syslog_identifier);
1515 c->syslog_identifier = NULL;
1523 strv_free(c->supplementary_groups);
1524 c->supplementary_groups = NULL;
1529 if (c->capabilities) {
1530 cap_free(c->capabilities);
1531 c->capabilities = NULL;
1534 strv_free(c->read_only_dirs);
1535 c->read_only_dirs = NULL;
1537 strv_free(c->read_write_dirs);
1538 c->read_write_dirs = NULL;
1540 strv_free(c->inaccessible_dirs);
1541 c->inaccessible_dirs = NULL;
1544 CPU_FREE(c->cpuset);
1550 void exec_command_done(ExecCommand *c) {
1560 void exec_command_done_array(ExecCommand *c, unsigned n) {
1563 for (i = 0; i < n; i++)
1564 exec_command_done(c+i);
1567 void exec_command_free_list(ExecCommand *c) {
1571 LIST_REMOVE(ExecCommand, command, c, i);
1572 exec_command_done(i);
1577 void exec_command_free_array(ExecCommand **c, unsigned n) {
1580 for (i = 0; i < n; i++) {
1581 exec_command_free_list(c[i]);
1586 int exec_context_load_environment(const ExecContext *c, char ***l) {
1587 char **i, **r = NULL;
1592 STRV_FOREACH(i, c->environment_files) {
1595 bool ignore = false;
1605 if (!path_is_absolute(fn)) {
1614 if ((k = load_env_file(fn, &p)) < 0) {
1628 m = strv_env_merge(2, r, p);
1644 static void strv_fprintf(FILE *f, char **l) {
1650 fprintf(f, " %s", *g);
1653 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
1665 "%sWorkingDirectory: %s\n"
1666 "%sRootDirectory: %s\n"
1667 "%sNonBlocking: %s\n"
1668 "%sPrivateTmp: %s\n"
1669 "%sControlGroupModify: %s\n"
1670 "%sControlGroupPersistent: %s\n"
1671 "%sPrivateNetwork: %s\n",
1673 prefix, c->working_directory ? c->working_directory : "/",
1674 prefix, c->root_directory ? c->root_directory : "/",
1675 prefix, yes_no(c->non_blocking),
1676 prefix, yes_no(c->private_tmp),
1677 prefix, yes_no(c->control_group_modify),
1678 prefix, yes_no(c->control_group_persistent),
1679 prefix, yes_no(c->private_network));
1681 STRV_FOREACH(e, c->environment)
1682 fprintf(f, "%sEnvironment: %s\n", prefix, *e);
1684 STRV_FOREACH(e, c->environment_files)
1685 fprintf(f, "%sEnvironmentFile: %s\n", prefix, *e);
1687 if (c->tcpwrap_name)
1689 "%sTCPWrapName: %s\n",
1690 prefix, c->tcpwrap_name);
1697 if (c->oom_score_adjust_set)
1699 "%sOOMScoreAdjust: %i\n",
1700 prefix, c->oom_score_adjust);
1702 for (i = 0; i < RLIM_NLIMITS; i++)
1704 fprintf(f, "%s%s: %llu\n", prefix, rlimit_to_string(i), (unsigned long long) c->rlimit[i]->rlim_max);
1708 "%sIOSchedulingClass: %s\n"
1709 "%sIOPriority: %i\n",
1710 prefix, ioprio_class_to_string(IOPRIO_PRIO_CLASS(c->ioprio)),
1711 prefix, (int) IOPRIO_PRIO_DATA(c->ioprio));
1713 if (c->cpu_sched_set)
1715 "%sCPUSchedulingPolicy: %s\n"
1716 "%sCPUSchedulingPriority: %i\n"
1717 "%sCPUSchedulingResetOnFork: %s\n",
1718 prefix, sched_policy_to_string(c->cpu_sched_policy),
1719 prefix, c->cpu_sched_priority,
1720 prefix, yes_no(c->cpu_sched_reset_on_fork));
1723 fprintf(f, "%sCPUAffinity:", prefix);
1724 for (i = 0; i < c->cpuset_ncpus; i++)
1725 if (CPU_ISSET_S(i, CPU_ALLOC_SIZE(c->cpuset_ncpus), c->cpuset))
1726 fprintf(f, " %i", i);
1730 if (c->timer_slack_nsec != (nsec_t) -1)
1731 fprintf(f, "%sTimerSlackNSec: %lu\n", prefix, (unsigned long)c->timer_slack_nsec);
1734 "%sStandardInput: %s\n"
1735 "%sStandardOutput: %s\n"
1736 "%sStandardError: %s\n",
1737 prefix, exec_input_to_string(c->std_input),
1738 prefix, exec_output_to_string(c->std_output),
1739 prefix, exec_output_to_string(c->std_error));
1745 "%sTTYVHangup: %s\n"
1746 "%sTTYVTDisallocate: %s\n",
1747 prefix, c->tty_path,
1748 prefix, yes_no(c->tty_reset),
1749 prefix, yes_no(c->tty_vhangup),
1750 prefix, yes_no(c->tty_vt_disallocate));
1752 if (c->std_output == EXEC_OUTPUT_SYSLOG || c->std_output == EXEC_OUTPUT_KMSG || c->std_output == EXEC_OUTPUT_JOURNAL ||
1753 c->std_output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_output == EXEC_OUTPUT_KMSG_AND_CONSOLE || c->std_output == EXEC_OUTPUT_JOURNAL_AND_CONSOLE ||
1754 c->std_error == EXEC_OUTPUT_SYSLOG || c->std_error == EXEC_OUTPUT_KMSG || c->std_error == EXEC_OUTPUT_JOURNAL ||
1755 c->std_error == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_error == EXEC_OUTPUT_KMSG_AND_CONSOLE || c->std_error == EXEC_OUTPUT_JOURNAL_AND_CONSOLE)
1757 "%sSyslogFacility: %s\n"
1758 "%sSyslogLevel: %s\n",
1759 prefix, log_facility_unshifted_to_string(c->syslog_priority >> 3),
1760 prefix, log_level_to_string(LOG_PRI(c->syslog_priority)));
1762 if (c->capabilities) {
1764 if ((t = cap_to_text(c->capabilities, NULL))) {
1765 fprintf(f, "%sCapabilities: %s\n",
1772 fprintf(f, "%sSecure Bits:%s%s%s%s%s%s\n",
1774 (c->secure_bits & SECURE_KEEP_CAPS) ? " keep-caps" : "",
1775 (c->secure_bits & SECURE_KEEP_CAPS_LOCKED) ? " keep-caps-locked" : "",
1776 (c->secure_bits & SECURE_NO_SETUID_FIXUP) ? " no-setuid-fixup" : "",
1777 (c->secure_bits & SECURE_NO_SETUID_FIXUP_LOCKED) ? " no-setuid-fixup-locked" : "",
1778 (c->secure_bits & SECURE_NOROOT) ? " noroot" : "",
1779 (c->secure_bits & SECURE_NOROOT_LOCKED) ? "noroot-locked" : "");
1781 if (c->capability_bounding_set_drop) {
1783 fprintf(f, "%sCapabilityBoundingSet:", prefix);
1785 for (l = 0; l <= cap_last_cap(); l++)
1786 if (!(c->capability_bounding_set_drop & ((uint64_t) 1ULL << (uint64_t) l))) {
1789 if ((t = cap_to_name(l))) {
1790 fprintf(f, " %s", t);
1799 fprintf(f, "%sUser: %s\n", prefix, c->user);
1801 fprintf(f, "%sGroup: %s\n", prefix, c->group);
1803 if (strv_length(c->supplementary_groups) > 0) {
1804 fprintf(f, "%sSupplementaryGroups:", prefix);
1805 strv_fprintf(f, c->supplementary_groups);
1810 fprintf(f, "%sPAMName: %s\n", prefix, c->pam_name);
1812 if (strv_length(c->read_write_dirs) > 0) {
1813 fprintf(f, "%sReadWriteDirs:", prefix);
1814 strv_fprintf(f, c->read_write_dirs);
1818 if (strv_length(c->read_only_dirs) > 0) {
1819 fprintf(f, "%sReadOnlyDirs:", prefix);
1820 strv_fprintf(f, c->read_only_dirs);
1824 if (strv_length(c->inaccessible_dirs) > 0) {
1825 fprintf(f, "%sInaccessibleDirs:", prefix);
1826 strv_fprintf(f, c->inaccessible_dirs);
1832 "%sKillSignal: SIG%s\n"
1833 "%sSendSIGKILL: %s\n"
1834 "%sIgnoreSIGPIPE: %s\n",
1835 prefix, kill_mode_to_string(c->kill_mode),
1836 prefix, signal_to_string(c->kill_signal),
1837 prefix, yes_no(c->send_sigkill),
1838 prefix, yes_no(c->ignore_sigpipe));
1842 "%sUtmpIdentifier: %s\n",
1843 prefix, c->utmp_id);
1846 void exec_status_start(ExecStatus *s, pid_t pid) {
1851 dual_timestamp_get(&s->start_timestamp);
1854 void exec_status_exit(ExecStatus *s, ExecContext *context, pid_t pid, int code, int status) {
1857 if (s->pid && s->pid != pid)
1861 dual_timestamp_get(&s->exit_timestamp);
1867 if (context->utmp_id)
1868 utmp_put_dead_process(context->utmp_id, pid, code, status);
1870 exec_context_tty_reset(context);
1874 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix) {
1875 char buf[FORMAT_TIMESTAMP_MAX];
1888 prefix, (unsigned long) s->pid);
1890 if (s->start_timestamp.realtime > 0)
1892 "%sStart Timestamp: %s\n",
1893 prefix, format_timestamp(buf, sizeof(buf), s->start_timestamp.realtime));
1895 if (s->exit_timestamp.realtime > 0)
1897 "%sExit Timestamp: %s\n"
1899 "%sExit Status: %i\n",
1900 prefix, format_timestamp(buf, sizeof(buf), s->exit_timestamp.realtime),
1901 prefix, sigchld_code_to_string(s->code),
1905 char *exec_command_line(char **argv) {
1913 STRV_FOREACH(a, argv)
1916 if (!(n = new(char, k)))
1920 STRV_FOREACH(a, argv) {
1927 if (strpbrk(*a, WHITESPACE)) {
1938 /* FIXME: this doesn't really handle arguments that have
1939 * spaces and ticks in them */
1944 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
1946 const char *prefix2;
1955 p2 = strappend(prefix, "\t");
1956 prefix2 = p2 ? p2 : prefix;
1958 cmd = exec_command_line(c->argv);
1961 "%sCommand Line: %s\n",
1962 prefix, cmd ? cmd : strerror(ENOMEM));
1966 exec_status_dump(&c->exec_status, f, prefix2);
1971 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {
1977 LIST_FOREACH(command, c, c)
1978 exec_command_dump(c, f, prefix);
1981 void exec_command_append_list(ExecCommand **l, ExecCommand *e) {
1988 /* It's kind of important, that we keep the order here */
1989 LIST_FIND_TAIL(ExecCommand, command, *l, end);
1990 LIST_INSERT_AFTER(ExecCommand, command, *l, end, e);
1995 int exec_command_set(ExecCommand *c, const char *path, ...) {
2003 l = strv_new_ap(path, ap);
2009 if (!(p = strdup(path))) {
2023 static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
2024 [EXEC_INPUT_NULL] = "null",
2025 [EXEC_INPUT_TTY] = "tty",
2026 [EXEC_INPUT_TTY_FORCE] = "tty-force",
2027 [EXEC_INPUT_TTY_FAIL] = "tty-fail",
2028 [EXEC_INPUT_SOCKET] = "socket"
2031 DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput);
2033 static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
2034 [EXEC_OUTPUT_INHERIT] = "inherit",
2035 [EXEC_OUTPUT_NULL] = "null",
2036 [EXEC_OUTPUT_TTY] = "tty",
2037 [EXEC_OUTPUT_SYSLOG] = "syslog",
2038 [EXEC_OUTPUT_SYSLOG_AND_CONSOLE] = "syslog+console",
2039 [EXEC_OUTPUT_KMSG] = "kmsg",
2040 [EXEC_OUTPUT_KMSG_AND_CONSOLE] = "kmsg+console",
2041 [EXEC_OUTPUT_JOURNAL] = "journal",
2042 [EXEC_OUTPUT_JOURNAL_AND_CONSOLE] = "journal+console",
2043 [EXEC_OUTPUT_SOCKET] = "socket"
2046 DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);
2048 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
2049 [KILL_CONTROL_GROUP] = "control-group",
2050 [KILL_PROCESS] = "process",
2051 [KILL_NONE] = "none"
2054 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);
2056 static const char* const kill_who_table[_KILL_WHO_MAX] = {
2057 [KILL_MAIN] = "main",
2058 [KILL_CONTROL] = "control",
2062 DEFINE_STRING_TABLE_LOOKUP(kill_who, KillWho);