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 General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
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>
42 #include <security/pam_appl.h>
51 #include "securebits.h"
53 #include "namespace.h"
55 #include "exit-status.h"
57 #include "utmp-wtmp.h"
59 #include "loopback-setup.h"
61 /* This assumes there is a 'tty' group */
64 static int shift_fds(int fds[], unsigned n_fds) {
65 int start, restart_from;
70 /* Modifies the fds array! (sorts it) */
80 for (i = start; i < (int) n_fds; i++) {
83 /* Already at right index? */
87 if ((nfd = fcntl(fds[i], F_DUPFD, i+3)) < 0)
90 close_nointr_nofail(fds[i]);
93 /* Hmm, the fd we wanted isn't free? Then
94 * let's remember that and try again from here*/
95 if (nfd != i+3 && restart_from < 0)
102 start = restart_from;
108 static int flags_fds(const int fds[], unsigned n_fds, bool nonblock) {
117 /* Drops/Sets O_NONBLOCK and FD_CLOEXEC from the file flags */
119 for (i = 0; i < n_fds; i++) {
121 if ((r = fd_nonblock(fds[i], nonblock)) < 0)
124 /* We unconditionally drop FD_CLOEXEC from the fds,
125 * since after all we want to pass these fds to our
128 if ((r = fd_cloexec(fds[i], false)) < 0)
135 static const char *tty_path(const ExecContext *context) {
138 if (context->tty_path)
139 return context->tty_path;
141 return "/dev/console";
144 void exec_context_tty_reset(const ExecContext *context) {
147 if (context->tty_vhangup)
148 terminal_vhangup(tty_path(context));
150 if (context->tty_reset)
151 reset_terminal(tty_path(context));
153 if (context->tty_vt_disallocate && context->tty_path)
154 vt_disallocate(context->tty_path);
157 static int open_null_as(int flags, int nfd) {
162 if ((fd = open("/dev/null", flags|O_NOCTTY)) < 0)
166 r = dup2(fd, nfd) < 0 ? -errno : nfd;
167 close_nointr_nofail(fd);
174 static int connect_logger_as(const ExecContext *context, ExecOutput output, const char *ident, int nfd) {
176 union sockaddr_union sa;
179 assert(output < _EXEC_OUTPUT_MAX);
183 fd = socket(AF_UNIX, SOCK_STREAM, 0);
188 sa.un.sun_family = AF_UNIX;
189 strncpy(sa.un.sun_path, "/run/systemd/journal/stdout", sizeof(sa.un.sun_path));
191 r = connect(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path));
193 close_nointr_nofail(fd);
197 if (shutdown(fd, SHUT_RD) < 0) {
198 close_nointr_nofail(fd);
209 context->syslog_identifier ? context->syslog_identifier : ident,
210 context->syslog_priority,
211 !!context->syslog_level_prefix,
212 output == EXEC_OUTPUT_SYSLOG || output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE,
213 output == EXEC_OUTPUT_KMSG || output == EXEC_OUTPUT_KMSG_AND_CONSOLE,
214 output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || output == EXEC_OUTPUT_KMSG_AND_CONSOLE || output == EXEC_OUTPUT_JOURNAL_AND_CONSOLE);
217 r = dup2(fd, nfd) < 0 ? -errno : nfd;
218 close_nointr_nofail(fd);
224 static int open_terminal_as(const char *path, mode_t mode, int nfd) {
230 if ((fd = open_terminal(path, mode | O_NOCTTY)) < 0)
234 r = dup2(fd, nfd) < 0 ? -errno : nfd;
235 close_nointr_nofail(fd);
242 static bool is_terminal_input(ExecInput i) {
244 i == EXEC_INPUT_TTY ||
245 i == EXEC_INPUT_TTY_FORCE ||
246 i == EXEC_INPUT_TTY_FAIL;
249 static int fixup_input(ExecInput std_input, int socket_fd, bool apply_tty_stdin) {
251 if (is_terminal_input(std_input) && !apply_tty_stdin)
252 return EXEC_INPUT_NULL;
254 if (std_input == EXEC_INPUT_SOCKET && socket_fd < 0)
255 return EXEC_INPUT_NULL;
260 static int fixup_output(ExecOutput std_output, int socket_fd) {
262 if (std_output == EXEC_OUTPUT_SOCKET && socket_fd < 0)
263 return EXEC_OUTPUT_INHERIT;
268 static int setup_input(const ExecContext *context, int socket_fd, bool apply_tty_stdin) {
273 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
277 case EXEC_INPUT_NULL:
278 return open_null_as(O_RDONLY, STDIN_FILENO);
281 case EXEC_INPUT_TTY_FORCE:
282 case EXEC_INPUT_TTY_FAIL: {
285 if ((fd = acquire_terminal(
287 i == EXEC_INPUT_TTY_FAIL,
288 i == EXEC_INPUT_TTY_FORCE,
292 if (fd != STDIN_FILENO) {
293 r = dup2(fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
294 close_nointr_nofail(fd);
301 case EXEC_INPUT_SOCKET:
302 return dup2(socket_fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
305 assert_not_reached("Unknown input type");
309 static int setup_output(const ExecContext *context, int socket_fd, const char *ident, bool apply_tty_stdin) {
316 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
317 o = fixup_output(context->std_output, socket_fd);
319 /* This expects the input is already set up */
323 case EXEC_OUTPUT_INHERIT:
325 /* If input got downgraded, inherit the original value */
326 if (i == EXEC_INPUT_NULL && is_terminal_input(context->std_input))
327 return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
329 /* If the input is connected to anything that's not a /dev/null, inherit that... */
330 if (i != EXEC_INPUT_NULL)
331 return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
333 /* If we are not started from PID 1 we just inherit STDOUT from our parent process. */
335 return STDOUT_FILENO;
337 /* We need to open /dev/null here anew, to get the
338 * right access mode. So we fall through */
340 case EXEC_OUTPUT_NULL:
341 return open_null_as(O_WRONLY, STDOUT_FILENO);
343 case EXEC_OUTPUT_TTY:
344 if (is_terminal_input(i))
345 return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
347 /* We don't reset the terminal if this is just about output */
348 return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
350 case EXEC_OUTPUT_SYSLOG:
351 case EXEC_OUTPUT_SYSLOG_AND_CONSOLE:
352 case EXEC_OUTPUT_KMSG:
353 case EXEC_OUTPUT_KMSG_AND_CONSOLE:
354 case EXEC_OUTPUT_JOURNAL:
355 case EXEC_OUTPUT_JOURNAL_AND_CONSOLE:
356 return connect_logger_as(context, o, ident, STDOUT_FILENO);
358 case EXEC_OUTPUT_SOCKET:
359 assert(socket_fd >= 0);
360 return dup2(socket_fd, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
363 assert_not_reached("Unknown output type");
367 static int setup_error(const ExecContext *context, int socket_fd, const char *ident, bool apply_tty_stdin) {
374 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
375 o = fixup_output(context->std_output, socket_fd);
376 e = fixup_output(context->std_error, socket_fd);
378 /* This expects the input and output are already set up */
380 /* Don't change the stderr file descriptor if we inherit all
381 * the way and are not on a tty */
382 if (e == EXEC_OUTPUT_INHERIT &&
383 o == EXEC_OUTPUT_INHERIT &&
384 i == EXEC_INPUT_NULL &&
385 !is_terminal_input(context->std_input) &&
387 return STDERR_FILENO;
389 /* Duplicate from stdout if possible */
390 if (e == o || e == EXEC_OUTPUT_INHERIT)
391 return dup2(STDOUT_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
395 case EXEC_OUTPUT_NULL:
396 return open_null_as(O_WRONLY, STDERR_FILENO);
398 case EXEC_OUTPUT_TTY:
399 if (is_terminal_input(i))
400 return dup2(STDIN_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
402 /* We don't reset the terminal if this is just about output */
403 return open_terminal_as(tty_path(context), O_WRONLY, STDERR_FILENO);
405 case EXEC_OUTPUT_SYSLOG:
406 case EXEC_OUTPUT_SYSLOG_AND_CONSOLE:
407 case EXEC_OUTPUT_KMSG:
408 case EXEC_OUTPUT_KMSG_AND_CONSOLE:
409 case EXEC_OUTPUT_JOURNAL:
410 case EXEC_OUTPUT_JOURNAL_AND_CONSOLE:
411 return connect_logger_as(context, e, ident, STDERR_FILENO);
413 case EXEC_OUTPUT_SOCKET:
414 assert(socket_fd >= 0);
415 return dup2(socket_fd, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
418 assert_not_reached("Unknown error type");
422 static int chown_terminal(int fd, uid_t uid) {
427 /* This might fail. What matters are the results. */
428 (void) fchown(fd, uid, -1);
429 (void) fchmod(fd, TTY_MODE);
431 if (fstat(fd, &st) < 0)
434 if (st.st_uid != uid || (st.st_mode & 0777) != TTY_MODE)
440 static int setup_confirm_stdio(const ExecContext *context,
442 int *_saved_stdout) {
443 int fd = -1, saved_stdin, saved_stdout = -1, r;
446 assert(_saved_stdin);
447 assert(_saved_stdout);
449 /* This returns positive EXIT_xxx return values instead of
450 * negative errno style values! */
452 if ((saved_stdin = fcntl(STDIN_FILENO, F_DUPFD, 3)) < 0)
455 if ((saved_stdout = fcntl(STDOUT_FILENO, F_DUPFD, 3)) < 0) {
460 if ((fd = acquire_terminal(
462 context->std_input == EXEC_INPUT_TTY_FAIL,
463 context->std_input == EXEC_INPUT_TTY_FORCE,
469 if (chown_terminal(fd, getuid()) < 0) {
474 if (dup2(fd, STDIN_FILENO) < 0) {
479 if (dup2(fd, STDOUT_FILENO) < 0) {
485 close_nointr_nofail(fd);
487 *_saved_stdin = saved_stdin;
488 *_saved_stdout = saved_stdout;
493 if (saved_stdout >= 0)
494 close_nointr_nofail(saved_stdout);
496 if (saved_stdin >= 0)
497 close_nointr_nofail(saved_stdin);
500 close_nointr_nofail(fd);
505 static int restore_confirm_stdio(const ExecContext *context,
513 assert(*saved_stdin >= 0);
514 assert(saved_stdout);
515 assert(*saved_stdout >= 0);
517 /* This returns positive EXIT_xxx return values instead of
518 * negative errno style values! */
520 if (is_terminal_input(context->std_input)) {
522 /* The service wants terminal input. */
526 context->std_output == EXEC_OUTPUT_INHERIT ||
527 context->std_output == EXEC_OUTPUT_TTY;
530 /* If the service doesn't want a controlling terminal,
531 * then we need to get rid entirely of what we have
534 if (release_terminal() < 0)
537 if (dup2(*saved_stdin, STDIN_FILENO) < 0)
540 if (dup2(*saved_stdout, STDOUT_FILENO) < 0)
543 *keep_stdout = *keep_stdin = false;
549 static int enforce_groups(const ExecContext *context, const char *username, gid_t gid) {
550 bool keep_groups = false;
555 /* Lookup and set GID and supplementary group list. Here too
556 * we avoid NSS lookups for gid=0. */
558 if (context->group || username) {
560 if (context->group) {
561 const char *g = context->group;
563 if ((r = get_group_creds(&g, &gid)) < 0)
567 /* First step, initialize groups from /etc/groups */
568 if (username && gid != 0) {
569 if (initgroups(username, gid) < 0)
575 /* Second step, set our gids */
576 if (setresgid(gid, gid, gid) < 0)
580 if (context->supplementary_groups) {
585 /* Final step, initialize any manually set supplementary groups */
586 assert_se((ngroups_max = (int) sysconf(_SC_NGROUPS_MAX)) > 0);
588 if (!(gids = new(gid_t, ngroups_max)))
592 if ((k = getgroups(ngroups_max, gids)) < 0) {
599 STRV_FOREACH(i, context->supplementary_groups) {
602 if (k >= ngroups_max) {
608 r = get_group_creds(&g, gids+k);
617 if (setgroups(k, gids) < 0) {
628 static int enforce_user(const ExecContext *context, uid_t uid) {
632 /* Sets (but doesn't lookup) the uid and make sure we keep the
633 * capabilities while doing so. */
635 if (context->capabilities) {
637 static const cap_value_t bits[] = {
638 CAP_SETUID, /* Necessary so that we can run setresuid() below */
639 CAP_SETPCAP /* Necessary so that we can set PR_SET_SECUREBITS later on */
642 /* First step: If we need to keep capabilities but
643 * drop privileges we need to make sure we keep our
644 * caps, whiel we drop privileges. */
646 int sb = context->secure_bits|SECURE_KEEP_CAPS;
648 if (prctl(PR_GET_SECUREBITS) != sb)
649 if (prctl(PR_SET_SECUREBITS, sb) < 0)
653 /* Second step: set the capabilities. This will reduce
654 * the capabilities to the minimum we need. */
656 if (!(d = cap_dup(context->capabilities)))
659 if (cap_set_flag(d, CAP_EFFECTIVE, ELEMENTSOF(bits), bits, CAP_SET) < 0 ||
660 cap_set_flag(d, CAP_PERMITTED, ELEMENTSOF(bits), bits, CAP_SET) < 0) {
666 if (cap_set_proc(d) < 0) {
675 /* Third step: actually set the uids */
676 if (setresuid(uid, uid, uid) < 0)
679 /* At this point we should have all necessary capabilities but
680 are otherwise a normal user. However, the caps might got
681 corrupted due to the setresuid() so we need clean them up
682 later. This is done outside of this call. */
689 static int null_conv(
691 const struct pam_message **msg,
692 struct pam_response **resp,
695 /* We don't support conversations */
700 static int setup_pam(
705 int fds[], unsigned n_fds) {
707 static const struct pam_conv conv = {
712 pam_handle_t *handle = NULL;
714 int pam_code = PAM_SUCCESS;
717 bool close_session = false;
718 pid_t pam_pid = 0, parent_pid;
724 /* We set up PAM in the parent process, then fork. The child
725 * will then stay around until killed via PR_GET_PDEATHSIG or
726 * systemd via the cgroup logic. It will then remove the PAM
727 * session again. The parent process will exec() the actual
728 * daemon. We do things this way to ensure that the main PID
729 * of the daemon is the one we initially fork()ed. */
731 if ((pam_code = pam_start(name, user, &conv, &handle)) != PAM_SUCCESS) {
737 if ((pam_code = pam_set_item(handle, PAM_TTY, tty)) != PAM_SUCCESS)
740 if ((pam_code = pam_acct_mgmt(handle, PAM_SILENT)) != PAM_SUCCESS)
743 if ((pam_code = pam_open_session(handle, PAM_SILENT)) != PAM_SUCCESS)
746 close_session = true;
748 if ((!(e = pam_getenvlist(handle)))) {
749 pam_code = PAM_BUF_ERR;
753 /* Block SIGTERM, so that we know that it won't get lost in
755 if (sigemptyset(&ss) < 0 ||
756 sigaddset(&ss, SIGTERM) < 0 ||
757 sigprocmask(SIG_BLOCK, &ss, &old_ss) < 0)
760 parent_pid = getpid();
762 if ((pam_pid = fork()) < 0)
769 /* The child's job is to reset the PAM session on
772 /* This string must fit in 10 chars (i.e. the length
773 * of "/sbin/init") */
774 rename_process("sd(PAM)");
776 /* Make sure we don't keep open the passed fds in this
777 child. We assume that otherwise only those fds are
778 open here that have been opened by PAM. */
779 close_many(fds, n_fds);
781 /* Wait until our parent died. This will most likely
782 * not work since the kernel does not allow
783 * unprivileged parents kill their privileged children
784 * this way. We rely on the control groups kill logic
785 * to do the rest for us. */
786 if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
789 /* Check if our parent process might already have
791 if (getppid() == parent_pid) {
793 if (sigwait(&ss, &sig) < 0) {
800 assert(sig == SIGTERM);
805 /* If our parent died we'll end the session */
806 if (getppid() != parent_pid)
807 if ((pam_code = pam_close_session(handle, PAM_DATA_SILENT)) != PAM_SUCCESS)
813 pam_end(handle, pam_code | PAM_DATA_SILENT);
817 /* If the child was forked off successfully it will do all the
818 * cleanups, so forget about the handle here. */
821 /* Unblock SIGTERM again in the parent */
822 if (sigprocmask(SIG_SETMASK, &old_ss, NULL) < 0)
825 /* We close the log explicitly here, since the PAM modules
826 * might have opened it, but we don't want this fd around. */
835 if (pam_code != PAM_SUCCESS)
836 err = -EPERM; /* PAM errors do not map to errno */
842 pam_code = pam_close_session(handle, PAM_DATA_SILENT);
844 pam_end(handle, pam_code | PAM_DATA_SILENT);
852 kill(pam_pid, SIGTERM);
853 kill(pam_pid, SIGCONT);
860 static int do_capability_bounding_set_drop(uint64_t drop) {
862 cap_t old_cap = NULL, new_cap = NULL;
866 /* If we are run as PID 1 we will lack CAP_SETPCAP by default
867 * in the effective set (yes, the kernel drops that when
868 * executing init!), so get it back temporarily so that we can
869 * call PR_CAPBSET_DROP. */
871 old_cap = cap_get_proc();
875 if (cap_get_flag(old_cap, CAP_SETPCAP, CAP_EFFECTIVE, &fv) < 0) {
881 static const cap_value_t v = CAP_SETPCAP;
883 new_cap = cap_dup(old_cap);
889 if (cap_set_flag(new_cap, CAP_EFFECTIVE, 1, &v, CAP_SET) < 0) {
894 if (cap_set_proc(new_cap) < 0) {
900 for (i = 0; i <= cap_last_cap(); i++)
901 if (drop & ((uint64_t) 1ULL << (uint64_t) i)) {
902 if (prctl(PR_CAPBSET_DROP, i) < 0) {
915 cap_set_proc(old_cap);
922 int exec_spawn(ExecCommand *command,
924 const ExecContext *context,
925 int fds[], unsigned n_fds,
927 bool apply_permissions,
929 bool apply_tty_stdin,
931 CGroupBonding *cgroup_bondings,
932 CGroupAttribute *cgroup_attributes,
939 char **files_env = NULL;
944 assert(fds || n_fds <= 0);
946 if (context->std_input == EXEC_INPUT_SOCKET ||
947 context->std_output == EXEC_OUTPUT_SOCKET ||
948 context->std_error == EXEC_OUTPUT_SOCKET) {
960 if ((r = exec_context_load_environment(context, &files_env)) < 0) {
961 log_error("Failed to load environment files: %s", strerror(-r));
966 argv = command->argv;
968 if (!(line = exec_command_line(argv))) {
973 log_debug("About to execute: %s", line);
976 r = cgroup_bonding_realize_list(cgroup_bondings);
980 cgroup_attribute_apply_list(cgroup_attributes, cgroup_bondings);
982 if ((pid = fork()) < 0) {
990 const char *username = NULL, *home = NULL;
991 uid_t uid = (uid_t) -1;
992 gid_t gid = (gid_t) -1;
993 char **our_env = NULL, **pam_env = NULL, **final_env = NULL, **final_argv = NULL;
995 int saved_stdout = -1, saved_stdin = -1;
996 bool keep_stdout = false, keep_stdin = false;
1000 /* This string must fit in 10 chars (i.e. the length
1001 * of "/sbin/init") */
1002 rename_process("sd(EXEC)");
1004 /* We reset exactly these signals, since they are the
1005 * only ones we set to SIG_IGN in the main daemon. All
1006 * others we leave untouched because we set them to
1007 * SIG_DFL or a valid handler initially, both of which
1008 * will be demoted to SIG_DFL. */
1009 default_signals(SIGNALS_CRASH_HANDLER,
1010 SIGNALS_IGNORE, -1);
1012 if (sigemptyset(&ss) < 0 ||
1013 sigprocmask(SIG_SETMASK, &ss, NULL) < 0) {
1015 r = EXIT_SIGNAL_MASK;
1019 /* Close sockets very early to make sure we don't
1020 * block init reexecution because it cannot bind its
1023 err = close_all_fds(socket_fd >= 0 ? &socket_fd : fds,
1024 socket_fd >= 0 ? 1 : n_fds);
1030 if (!context->same_pgrp)
1037 if (context->tcpwrap_name) {
1039 if (!socket_tcpwrap(socket_fd, context->tcpwrap_name)) {
1045 for (i = 0; i < (int) n_fds; i++) {
1046 if (!socket_tcpwrap(fds[i], context->tcpwrap_name)) {
1054 exec_context_tty_reset(context);
1056 /* We skip the confirmation step if we shall not apply the TTY */
1057 if (confirm_spawn &&
1058 (!is_terminal_input(context->std_input) || apply_tty_stdin)) {
1061 /* Set up terminal for the question */
1062 if ((r = setup_confirm_stdio(context,
1063 &saved_stdin, &saved_stdout))) {
1068 /* Now ask the question. */
1069 if (!(line = exec_command_line(argv))) {
1075 r = ask(&response, "yns", "Execute %s? [Yes, No, Skip] ", line);
1078 if (r < 0 || response == 'n') {
1082 } else if (response == 's') {
1087 /* Release terminal for the question */
1088 if ((r = restore_confirm_stdio(context,
1089 &saved_stdin, &saved_stdout,
1090 &keep_stdin, &keep_stdout))) {
1096 /* If a socket is connected to STDIN/STDOUT/STDERR, we
1097 * must sure to drop O_NONBLOCK */
1099 fd_nonblock(socket_fd, false);
1102 err = setup_input(context, socket_fd, apply_tty_stdin);
1110 err = setup_output(context, socket_fd, file_name_from_path(command->path), apply_tty_stdin);
1117 err = setup_error(context, socket_fd, file_name_from_path(command->path), apply_tty_stdin);
1123 if (cgroup_bondings) {
1124 err = cgroup_bonding_install_list(cgroup_bondings, 0);
1131 if (context->oom_score_adjust_set) {
1134 snprintf(t, sizeof(t), "%i", context->oom_score_adjust);
1137 if (write_one_line_file("/proc/self/oom_score_adj", t) < 0) {
1138 /* Compatibility with Linux <= 2.6.35 */
1142 adj = (context->oom_score_adjust * -OOM_DISABLE) / OOM_SCORE_ADJ_MAX;
1143 adj = CLAMP(adj, OOM_DISABLE, OOM_ADJUST_MAX);
1145 snprintf(t, sizeof(t), "%i", adj);
1148 if (write_one_line_file("/proc/self/oom_adj", t) < 0
1149 && errno != EACCES) {
1151 r = EXIT_OOM_ADJUST;
1157 if (context->nice_set)
1158 if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
1164 if (context->cpu_sched_set) {
1165 struct sched_param param;
1168 param.sched_priority = context->cpu_sched_priority;
1170 if (sched_setscheduler(0, context->cpu_sched_policy |
1171 (context->cpu_sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0), ¶m) < 0) {
1173 r = EXIT_SETSCHEDULER;
1178 if (context->cpuset)
1179 if (sched_setaffinity(0, CPU_ALLOC_SIZE(context->cpuset_ncpus), context->cpuset) < 0) {
1181 r = EXIT_CPUAFFINITY;
1185 if (context->ioprio_set)
1186 if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
1192 if (context->timer_slack_nsec_set)
1193 if (prctl(PR_SET_TIMERSLACK, context->timer_slack_nsec) < 0) {
1195 r = EXIT_TIMERSLACK;
1199 if (context->utmp_id)
1200 utmp_put_init_process(context->utmp_id, getpid(), getsid(0), context->tty_path);
1202 if (context->user) {
1203 username = context->user;
1204 err = get_user_creds(&username, &uid, &gid, &home);
1210 if (is_terminal_input(context->std_input)) {
1211 err = chown_terminal(STDIN_FILENO, uid);
1218 if (cgroup_bondings && context->control_group_modify) {
1219 err = cgroup_bonding_set_group_access_list(cgroup_bondings, 0755, uid, gid);
1221 err = cgroup_bonding_set_task_access_list(cgroup_bondings, 0644, uid, gid);
1229 if (apply_permissions) {
1230 err = enforce_groups(context, username, gid);
1237 umask(context->umask);
1240 if (context->pam_name && username) {
1241 err = setup_pam(context->pam_name, username, context->tty_path, &pam_env, fds, n_fds);
1248 if (context->private_network) {
1249 if (unshare(CLONE_NEWNET) < 0) {
1258 if (strv_length(context->read_write_dirs) > 0 ||
1259 strv_length(context->read_only_dirs) > 0 ||
1260 strv_length(context->inaccessible_dirs) > 0 ||
1261 context->mount_flags != MS_SHARED ||
1262 context->private_tmp) {
1263 err = setup_namespace(context->read_write_dirs,
1264 context->read_only_dirs,
1265 context->inaccessible_dirs,
1266 context->private_tmp,
1267 context->mount_flags);
1275 if (context->root_directory)
1276 if (chroot(context->root_directory) < 0) {
1282 if (chdir(context->working_directory ? context->working_directory : "/") < 0) {
1291 if (asprintf(&d, "%s/%s",
1292 context->root_directory ? context->root_directory : "",
1293 context->working_directory ? context->working_directory : "") < 0) {
1309 /* We repeat the fd closing here, to make sure that
1310 * nothing is leaked from the PAM modules */
1311 err = close_all_fds(fds, n_fds);
1313 err = shift_fds(fds, n_fds);
1315 err = flags_fds(fds, n_fds, context->non_blocking);
1321 if (apply_permissions) {
1323 for (i = 0; i < RLIMIT_NLIMITS; i++) {
1324 if (!context->rlimit[i])
1327 if (setrlimit(i, context->rlimit[i]) < 0) {
1334 if (context->capability_bounding_set_drop) {
1335 err = do_capability_bounding_set_drop(context->capability_bounding_set_drop);
1337 r = EXIT_CAPABILITIES;
1342 if (context->user) {
1343 err = enforce_user(context, uid);
1350 /* PR_GET_SECUREBITS is not privileged, while
1351 * PR_SET_SECUREBITS is. So to suppress
1352 * potential EPERMs we'll try not to call
1353 * PR_SET_SECUREBITS unless necessary. */
1354 if (prctl(PR_GET_SECUREBITS) != context->secure_bits)
1355 if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {
1357 r = EXIT_SECUREBITS;
1361 if (context->capabilities)
1362 if (cap_set_proc(context->capabilities) < 0) {
1364 r = EXIT_CAPABILITIES;
1369 if (!(our_env = new0(char*, 7))) {
1376 if (asprintf(our_env + n_env++, "LISTEN_PID=%lu", (unsigned long) getpid()) < 0 ||
1377 asprintf(our_env + n_env++, "LISTEN_FDS=%u", n_fds) < 0) {
1384 if (asprintf(our_env + n_env++, "HOME=%s", home) < 0) {
1391 if (asprintf(our_env + n_env++, "LOGNAME=%s", username) < 0 ||
1392 asprintf(our_env + n_env++, "USER=%s", username) < 0) {
1398 if (is_terminal_input(context->std_input) ||
1399 context->std_output == EXEC_OUTPUT_TTY ||
1400 context->std_error == EXEC_OUTPUT_TTY)
1401 if (!(our_env[n_env++] = strdup(default_term_for_tty(tty_path(context))))) {
1409 if (!(final_env = strv_env_merge(
1413 context->environment,
1422 if (!(final_argv = replace_env_argv(argv, final_env))) {
1428 final_env = strv_env_clean(final_env);
1430 execve(command->path, final_argv, final_env);
1437 log_warning("Failed at step %s spawning %s: %s",
1438 exit_status_to_string(r, EXIT_STATUS_SYSTEMD),
1439 command->path, strerror(-err));
1443 strv_free(final_env);
1445 strv_free(files_env);
1446 strv_free(final_argv);
1448 if (saved_stdin >= 0)
1449 close_nointr_nofail(saved_stdin);
1451 if (saved_stdout >= 0)
1452 close_nointr_nofail(saved_stdout);
1457 strv_free(files_env);
1459 /* We add the new process to the cgroup both in the child (so
1460 * that we can be sure that no user code is ever executed
1461 * outside of the cgroup) and in the parent (so that we can be
1462 * sure that when we kill the cgroup the process will be
1464 if (cgroup_bondings)
1465 cgroup_bonding_install_list(cgroup_bondings, pid);
1467 log_debug("Forked %s as %lu", command->path, (unsigned long) pid);
1469 exec_status_start(&command->exec_status, pid);
1475 strv_free(files_env);
1480 void exec_context_init(ExecContext *c) {
1484 c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
1485 c->cpu_sched_policy = SCHED_OTHER;
1486 c->syslog_priority = LOG_DAEMON|LOG_INFO;
1487 c->syslog_level_prefix = true;
1488 c->mount_flags = MS_SHARED;
1489 c->kill_signal = SIGTERM;
1490 c->send_sigkill = true;
1493 void exec_context_done(ExecContext *c) {
1498 strv_free(c->environment);
1499 c->environment = NULL;
1501 strv_free(c->environment_files);
1502 c->environment_files = NULL;
1504 for (l = 0; l < ELEMENTSOF(c->rlimit); l++) {
1506 c->rlimit[l] = NULL;
1509 free(c->working_directory);
1510 c->working_directory = NULL;
1511 free(c->root_directory);
1512 c->root_directory = NULL;
1517 free(c->tcpwrap_name);
1518 c->tcpwrap_name = NULL;
1520 free(c->syslog_identifier);
1521 c->syslog_identifier = NULL;
1529 strv_free(c->supplementary_groups);
1530 c->supplementary_groups = NULL;
1535 if (c->capabilities) {
1536 cap_free(c->capabilities);
1537 c->capabilities = NULL;
1540 strv_free(c->read_only_dirs);
1541 c->read_only_dirs = NULL;
1543 strv_free(c->read_write_dirs);
1544 c->read_write_dirs = NULL;
1546 strv_free(c->inaccessible_dirs);
1547 c->inaccessible_dirs = NULL;
1550 CPU_FREE(c->cpuset);
1556 void exec_command_done(ExecCommand *c) {
1566 void exec_command_done_array(ExecCommand *c, unsigned n) {
1569 for (i = 0; i < n; i++)
1570 exec_command_done(c+i);
1573 void exec_command_free_list(ExecCommand *c) {
1577 LIST_REMOVE(ExecCommand, command, c, i);
1578 exec_command_done(i);
1583 void exec_command_free_array(ExecCommand **c, unsigned n) {
1586 for (i = 0; i < n; i++) {
1587 exec_command_free_list(c[i]);
1592 int exec_context_load_environment(const ExecContext *c, char ***l) {
1593 char **i, **r = NULL;
1598 STRV_FOREACH(i, c->environment_files) {
1601 bool ignore = false;
1611 if (!path_is_absolute(fn)) {
1620 if ((k = load_env_file(fn, &p)) < 0) {
1634 m = strv_env_merge(2, r, p);
1650 static void strv_fprintf(FILE *f, char **l) {
1656 fprintf(f, " %s", *g);
1659 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
1671 "%sWorkingDirectory: %s\n"
1672 "%sRootDirectory: %s\n"
1673 "%sNonBlocking: %s\n"
1674 "%sPrivateTmp: %s\n"
1675 "%sControlGroupModify: %s\n"
1676 "%sPrivateNetwork: %s\n",
1678 prefix, c->working_directory ? c->working_directory : "/",
1679 prefix, c->root_directory ? c->root_directory : "/",
1680 prefix, yes_no(c->non_blocking),
1681 prefix, yes_no(c->private_tmp),
1682 prefix, yes_no(c->control_group_modify),
1683 prefix, yes_no(c->private_network));
1685 STRV_FOREACH(e, c->environment)
1686 fprintf(f, "%sEnvironment: %s\n", prefix, *e);
1688 STRV_FOREACH(e, c->environment_files)
1689 fprintf(f, "%sEnvironmentFile: %s\n", prefix, *e);
1691 if (c->tcpwrap_name)
1693 "%sTCPWrapName: %s\n",
1694 prefix, c->tcpwrap_name);
1701 if (c->oom_score_adjust_set)
1703 "%sOOMScoreAdjust: %i\n",
1704 prefix, c->oom_score_adjust);
1706 for (i = 0; i < RLIM_NLIMITS; i++)
1708 fprintf(f, "%s%s: %llu\n", prefix, rlimit_to_string(i), (unsigned long long) c->rlimit[i]->rlim_max);
1712 "%sIOSchedulingClass: %s\n"
1713 "%sIOPriority: %i\n",
1714 prefix, ioprio_class_to_string(IOPRIO_PRIO_CLASS(c->ioprio)),
1715 prefix, (int) IOPRIO_PRIO_DATA(c->ioprio));
1717 if (c->cpu_sched_set)
1719 "%sCPUSchedulingPolicy: %s\n"
1720 "%sCPUSchedulingPriority: %i\n"
1721 "%sCPUSchedulingResetOnFork: %s\n",
1722 prefix, sched_policy_to_string(c->cpu_sched_policy),
1723 prefix, c->cpu_sched_priority,
1724 prefix, yes_no(c->cpu_sched_reset_on_fork));
1727 fprintf(f, "%sCPUAffinity:", prefix);
1728 for (i = 0; i < c->cpuset_ncpus; i++)
1729 if (CPU_ISSET_S(i, CPU_ALLOC_SIZE(c->cpuset_ncpus), c->cpuset))
1730 fprintf(f, " %i", i);
1734 if (c->timer_slack_nsec_set)
1735 fprintf(f, "%sTimerSlackNSec: %lu\n", prefix, c->timer_slack_nsec);
1738 "%sStandardInput: %s\n"
1739 "%sStandardOutput: %s\n"
1740 "%sStandardError: %s\n",
1741 prefix, exec_input_to_string(c->std_input),
1742 prefix, exec_output_to_string(c->std_output),
1743 prefix, exec_output_to_string(c->std_error));
1749 "%sTTYVHangup: %s\n"
1750 "%sTTYVTDisallocate: %s\n",
1751 prefix, c->tty_path,
1752 prefix, yes_no(c->tty_reset),
1753 prefix, yes_no(c->tty_vhangup),
1754 prefix, yes_no(c->tty_vt_disallocate));
1756 if (c->std_output == EXEC_OUTPUT_SYSLOG || c->std_output == EXEC_OUTPUT_KMSG || c->std_output == EXEC_OUTPUT_JOURNAL ||
1757 c->std_output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_output == EXEC_OUTPUT_KMSG_AND_CONSOLE || c->std_output == EXEC_OUTPUT_JOURNAL_AND_CONSOLE ||
1758 c->std_error == EXEC_OUTPUT_SYSLOG || c->std_error == EXEC_OUTPUT_KMSG || c->std_error == EXEC_OUTPUT_JOURNAL ||
1759 c->std_error == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_error == EXEC_OUTPUT_KMSG_AND_CONSOLE || c->std_error == EXEC_OUTPUT_JOURNAL_AND_CONSOLE)
1761 "%sSyslogFacility: %s\n"
1762 "%sSyslogLevel: %s\n",
1763 prefix, log_facility_unshifted_to_string(c->syslog_priority >> 3),
1764 prefix, log_level_to_string(LOG_PRI(c->syslog_priority)));
1766 if (c->capabilities) {
1768 if ((t = cap_to_text(c->capabilities, NULL))) {
1769 fprintf(f, "%sCapabilities: %s\n",
1776 fprintf(f, "%sSecure Bits:%s%s%s%s%s%s\n",
1778 (c->secure_bits & SECURE_KEEP_CAPS) ? " keep-caps" : "",
1779 (c->secure_bits & SECURE_KEEP_CAPS_LOCKED) ? " keep-caps-locked" : "",
1780 (c->secure_bits & SECURE_NO_SETUID_FIXUP) ? " no-setuid-fixup" : "",
1781 (c->secure_bits & SECURE_NO_SETUID_FIXUP_LOCKED) ? " no-setuid-fixup-locked" : "",
1782 (c->secure_bits & SECURE_NOROOT) ? " noroot" : "",
1783 (c->secure_bits & SECURE_NOROOT_LOCKED) ? "noroot-locked" : "");
1785 if (c->capability_bounding_set_drop) {
1787 fprintf(f, "%sCapabilityBoundingSet:", prefix);
1789 for (l = 0; l <= cap_last_cap(); l++)
1790 if (!(c->capability_bounding_set_drop & ((uint64_t) 1ULL << (uint64_t) l))) {
1793 if ((t = cap_to_name(l))) {
1794 fprintf(f, " %s", t);
1803 fprintf(f, "%sUser: %s\n", prefix, c->user);
1805 fprintf(f, "%sGroup: %s\n", prefix, c->group);
1807 if (strv_length(c->supplementary_groups) > 0) {
1808 fprintf(f, "%sSupplementaryGroups:", prefix);
1809 strv_fprintf(f, c->supplementary_groups);
1814 fprintf(f, "%sPAMName: %s\n", prefix, c->pam_name);
1816 if (strv_length(c->read_write_dirs) > 0) {
1817 fprintf(f, "%sReadWriteDirs:", prefix);
1818 strv_fprintf(f, c->read_write_dirs);
1822 if (strv_length(c->read_only_dirs) > 0) {
1823 fprintf(f, "%sReadOnlyDirs:", prefix);
1824 strv_fprintf(f, c->read_only_dirs);
1828 if (strv_length(c->inaccessible_dirs) > 0) {
1829 fprintf(f, "%sInaccessibleDirs:", prefix);
1830 strv_fprintf(f, c->inaccessible_dirs);
1836 "%sKillSignal: SIG%s\n"
1837 "%sSendSIGKILL: %s\n",
1838 prefix, kill_mode_to_string(c->kill_mode),
1839 prefix, signal_to_string(c->kill_signal),
1840 prefix, yes_no(c->send_sigkill));
1844 "%sUtmpIdentifier: %s\n",
1845 prefix, c->utmp_id);
1848 void exec_status_start(ExecStatus *s, pid_t pid) {
1853 dual_timestamp_get(&s->start_timestamp);
1856 void exec_status_exit(ExecStatus *s, ExecContext *context, pid_t pid, int code, int status) {
1859 if (s->pid && s->pid != pid)
1863 dual_timestamp_get(&s->exit_timestamp);
1869 if (context->utmp_id)
1870 utmp_put_dead_process(context->utmp_id, pid, code, status);
1872 exec_context_tty_reset(context);
1876 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix) {
1877 char buf[FORMAT_TIMESTAMP_MAX];
1890 prefix, (unsigned long) s->pid);
1892 if (s->start_timestamp.realtime > 0)
1894 "%sStart Timestamp: %s\n",
1895 prefix, format_timestamp(buf, sizeof(buf), s->start_timestamp.realtime));
1897 if (s->exit_timestamp.realtime > 0)
1899 "%sExit Timestamp: %s\n"
1901 "%sExit Status: %i\n",
1902 prefix, format_timestamp(buf, sizeof(buf), s->exit_timestamp.realtime),
1903 prefix, sigchld_code_to_string(s->code),
1907 char *exec_command_line(char **argv) {
1915 STRV_FOREACH(a, argv)
1918 if (!(n = new(char, k)))
1922 STRV_FOREACH(a, argv) {
1929 if (strpbrk(*a, WHITESPACE)) {
1940 /* FIXME: this doesn't really handle arguments that have
1941 * spaces and ticks in them */
1946 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
1948 const char *prefix2;
1957 p2 = strappend(prefix, "\t");
1958 prefix2 = p2 ? p2 : prefix;
1960 cmd = exec_command_line(c->argv);
1963 "%sCommand Line: %s\n",
1964 prefix, cmd ? cmd : strerror(ENOMEM));
1968 exec_status_dump(&c->exec_status, f, prefix2);
1973 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {
1979 LIST_FOREACH(command, c, c)
1980 exec_command_dump(c, f, prefix);
1983 void exec_command_append_list(ExecCommand **l, ExecCommand *e) {
1990 /* It's kind of important, that we keep the order here */
1991 LIST_FIND_TAIL(ExecCommand, command, *l, end);
1992 LIST_INSERT_AFTER(ExecCommand, command, *l, end, e);
1997 int exec_command_set(ExecCommand *c, const char *path, ...) {
2005 l = strv_new_ap(path, ap);
2011 if (!(p = strdup(path))) {
2025 static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
2026 [EXEC_INPUT_NULL] = "null",
2027 [EXEC_INPUT_TTY] = "tty",
2028 [EXEC_INPUT_TTY_FORCE] = "tty-force",
2029 [EXEC_INPUT_TTY_FAIL] = "tty-fail",
2030 [EXEC_INPUT_SOCKET] = "socket"
2033 DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput);
2035 static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
2036 [EXEC_OUTPUT_INHERIT] = "inherit",
2037 [EXEC_OUTPUT_NULL] = "null",
2038 [EXEC_OUTPUT_TTY] = "tty",
2039 [EXEC_OUTPUT_SYSLOG] = "syslog",
2040 [EXEC_OUTPUT_SYSLOG_AND_CONSOLE] = "syslog+console",
2041 [EXEC_OUTPUT_KMSG] = "kmsg",
2042 [EXEC_OUTPUT_KMSG_AND_CONSOLE] = "kmsg+console",
2043 [EXEC_OUTPUT_JOURNAL] = "journal",
2044 [EXEC_OUTPUT_JOURNAL_AND_CONSOLE] = "journal+console",
2045 [EXEC_OUTPUT_SOCKET] = "socket"
2048 DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);
2050 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
2051 [KILL_CONTROL_GROUP] = "control-group",
2052 [KILL_PROCESS] = "process",
2053 [KILL_NONE] = "none"
2056 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);
2058 static const char* const kill_who_table[_KILL_WHO_MAX] = {
2059 [KILL_MAIN] = "main",
2060 [KILL_CONTROL] = "control",
2064 DEFINE_STRING_TABLE_LOOKUP(kill_who, KillWho);