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) {
178 struct sockaddr_un un;
182 assert(output < _EXEC_OUTPUT_MAX);
186 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
190 sa.sa.sa_family = AF_UNIX;
191 strncpy(sa.un.sun_path, STDOUT_SYSLOG_BRIDGE_SOCKET, sizeof(sa.un.sun_path));
193 if (connect(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + sizeof(STDOUT_SYSLOG_BRIDGE_SOCKET) - 1) < 0) {
194 close_nointr_nofail(fd);
198 if (shutdown(fd, SHUT_RD) < 0) {
199 close_nointr_nofail(fd);
203 /* We speak a very simple protocol between log server
204 * and client: one line for the log destination (kmsg
205 * or syslog), followed by the priority field,
206 * followed by the process name. Since we replaced
207 * stdin/stderr we simple use stdio to write to
208 * it. Note that we use stderr, to minimize buffer
209 * flushing issues. */
216 output == EXEC_OUTPUT_KMSG ? "kmsg" :
217 output == EXEC_OUTPUT_KMSG_AND_CONSOLE ? "kmsg+console" :
218 output == EXEC_OUTPUT_SYSLOG ? "syslog" :
220 context->syslog_priority,
221 context->syslog_identifier ? context->syslog_identifier : ident,
222 context->syslog_level_prefix);
225 r = dup2(fd, nfd) < 0 ? -errno : nfd;
226 close_nointr_nofail(fd);
232 static int open_terminal_as(const char *path, mode_t mode, int nfd) {
238 if ((fd = open_terminal(path, mode | O_NOCTTY)) < 0)
242 r = dup2(fd, nfd) < 0 ? -errno : nfd;
243 close_nointr_nofail(fd);
250 static bool is_terminal_input(ExecInput i) {
252 i == EXEC_INPUT_TTY ||
253 i == EXEC_INPUT_TTY_FORCE ||
254 i == EXEC_INPUT_TTY_FAIL;
257 static int fixup_input(ExecInput std_input, int socket_fd, bool apply_tty_stdin) {
259 if (is_terminal_input(std_input) && !apply_tty_stdin)
260 return EXEC_INPUT_NULL;
262 if (std_input == EXEC_INPUT_SOCKET && socket_fd < 0)
263 return EXEC_INPUT_NULL;
268 static int fixup_output(ExecOutput std_output, int socket_fd) {
270 if (std_output == EXEC_OUTPUT_SOCKET && socket_fd < 0)
271 return EXEC_OUTPUT_INHERIT;
276 static int setup_input(const ExecContext *context, int socket_fd, bool apply_tty_stdin) {
281 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
285 case EXEC_INPUT_NULL:
286 return open_null_as(O_RDONLY, STDIN_FILENO);
289 case EXEC_INPUT_TTY_FORCE:
290 case EXEC_INPUT_TTY_FAIL: {
293 if ((fd = acquire_terminal(
295 i == EXEC_INPUT_TTY_FAIL,
296 i == EXEC_INPUT_TTY_FORCE,
300 if (fd != STDIN_FILENO) {
301 r = dup2(fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
302 close_nointr_nofail(fd);
309 case EXEC_INPUT_SOCKET:
310 return dup2(socket_fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
313 assert_not_reached("Unknown input type");
317 static int setup_output(const ExecContext *context, int socket_fd, const char *ident, bool apply_tty_stdin) {
324 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
325 o = fixup_output(context->std_output, socket_fd);
327 /* This expects the input is already set up */
331 case EXEC_OUTPUT_INHERIT:
333 /* If input got downgraded, inherit the original value */
334 if (i == EXEC_INPUT_NULL && is_terminal_input(context->std_input))
335 return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
337 /* If the input is connected to anything that's not a /dev/null, inherit that... */
338 if (i != EXEC_INPUT_NULL)
339 return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
341 /* If we are not started from PID 1 we just inherit STDOUT from our parent process. */
343 return STDOUT_FILENO;
345 /* We need to open /dev/null here anew, to get the
346 * right access mode. So we fall through */
348 case EXEC_OUTPUT_NULL:
349 return open_null_as(O_WRONLY, STDOUT_FILENO);
351 case EXEC_OUTPUT_TTY:
352 if (is_terminal_input(i))
353 return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
355 /* We don't reset the terminal if this is just about output */
356 return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
358 case EXEC_OUTPUT_SYSLOG:
359 case EXEC_OUTPUT_SYSLOG_AND_CONSOLE:
360 case EXEC_OUTPUT_KMSG:
361 case EXEC_OUTPUT_KMSG_AND_CONSOLE:
362 return connect_logger_as(context, o, ident, STDOUT_FILENO);
364 case EXEC_OUTPUT_SOCKET:
365 assert(socket_fd >= 0);
366 return dup2(socket_fd, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
369 assert_not_reached("Unknown output type");
373 static int setup_error(const ExecContext *context, int socket_fd, const char *ident, bool apply_tty_stdin) {
380 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
381 o = fixup_output(context->std_output, socket_fd);
382 e = fixup_output(context->std_error, socket_fd);
384 /* This expects the input and output are already set up */
386 /* Don't change the stderr file descriptor if we inherit all
387 * the way and are not on a tty */
388 if (e == EXEC_OUTPUT_INHERIT &&
389 o == EXEC_OUTPUT_INHERIT &&
390 i == EXEC_INPUT_NULL &&
391 !is_terminal_input(context->std_input) &&
393 return STDERR_FILENO;
395 /* Duplicate from stdout if possible */
396 if (e == o || e == EXEC_OUTPUT_INHERIT)
397 return dup2(STDOUT_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
401 case EXEC_OUTPUT_NULL:
402 return open_null_as(O_WRONLY, STDERR_FILENO);
404 case EXEC_OUTPUT_TTY:
405 if (is_terminal_input(i))
406 return dup2(STDIN_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
408 /* We don't reset the terminal if this is just about output */
409 return open_terminal_as(tty_path(context), O_WRONLY, STDERR_FILENO);
411 case EXEC_OUTPUT_SYSLOG:
412 case EXEC_OUTPUT_SYSLOG_AND_CONSOLE:
413 case EXEC_OUTPUT_KMSG:
414 case EXEC_OUTPUT_KMSG_AND_CONSOLE:
415 return connect_logger_as(context, e, ident, STDERR_FILENO);
417 case EXEC_OUTPUT_SOCKET:
418 assert(socket_fd >= 0);
419 return dup2(socket_fd, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
422 assert_not_reached("Unknown error type");
426 static int chown_terminal(int fd, uid_t uid) {
431 /* This might fail. What matters are the results. */
432 (void) fchown(fd, uid, -1);
433 (void) fchmod(fd, TTY_MODE);
435 if (fstat(fd, &st) < 0)
438 if (st.st_uid != uid || (st.st_mode & 0777) != TTY_MODE)
444 static int setup_confirm_stdio(const ExecContext *context,
446 int *_saved_stdout) {
447 int fd = -1, saved_stdin, saved_stdout = -1, r;
450 assert(_saved_stdin);
451 assert(_saved_stdout);
453 /* This returns positive EXIT_xxx return values instead of
454 * negative errno style values! */
456 if ((saved_stdin = fcntl(STDIN_FILENO, F_DUPFD, 3)) < 0)
459 if ((saved_stdout = fcntl(STDOUT_FILENO, F_DUPFD, 3)) < 0) {
464 if ((fd = acquire_terminal(
466 context->std_input == EXEC_INPUT_TTY_FAIL,
467 context->std_input == EXEC_INPUT_TTY_FORCE,
473 if (chown_terminal(fd, getuid()) < 0) {
478 if (dup2(fd, STDIN_FILENO) < 0) {
483 if (dup2(fd, STDOUT_FILENO) < 0) {
489 close_nointr_nofail(fd);
491 *_saved_stdin = saved_stdin;
492 *_saved_stdout = saved_stdout;
497 if (saved_stdout >= 0)
498 close_nointr_nofail(saved_stdout);
500 if (saved_stdin >= 0)
501 close_nointr_nofail(saved_stdin);
504 close_nointr_nofail(fd);
509 static int restore_confirm_stdio(const ExecContext *context,
517 assert(*saved_stdin >= 0);
518 assert(saved_stdout);
519 assert(*saved_stdout >= 0);
521 /* This returns positive EXIT_xxx return values instead of
522 * negative errno style values! */
524 if (is_terminal_input(context->std_input)) {
526 /* The service wants terminal input. */
530 context->std_output == EXEC_OUTPUT_INHERIT ||
531 context->std_output == EXEC_OUTPUT_TTY;
534 /* If the service doesn't want a controlling terminal,
535 * then we need to get rid entirely of what we have
538 if (release_terminal() < 0)
541 if (dup2(*saved_stdin, STDIN_FILENO) < 0)
544 if (dup2(*saved_stdout, STDOUT_FILENO) < 0)
547 *keep_stdout = *keep_stdin = false;
553 static int enforce_groups(const ExecContext *context, const char *username, gid_t gid) {
554 bool keep_groups = false;
559 /* Lookup and set GID and supplementary group list. Here too
560 * we avoid NSS lookups for gid=0. */
562 if (context->group || username) {
564 if (context->group) {
565 const char *g = context->group;
567 if ((r = get_group_creds(&g, &gid)) < 0)
571 /* First step, initialize groups from /etc/groups */
572 if (username && gid != 0) {
573 if (initgroups(username, gid) < 0)
579 /* Second step, set our gids */
580 if (setresgid(gid, gid, gid) < 0)
584 if (context->supplementary_groups) {
589 /* Final step, initialize any manually set supplementary groups */
590 assert_se((ngroups_max = (int) sysconf(_SC_NGROUPS_MAX)) > 0);
592 if (!(gids = new(gid_t, ngroups_max)))
596 if ((k = getgroups(ngroups_max, gids)) < 0) {
603 STRV_FOREACH(i, context->supplementary_groups) {
606 if (k >= ngroups_max) {
612 r = get_group_creds(&g, gids+k);
621 if (setgroups(k, gids) < 0) {
632 static int enforce_user(const ExecContext *context, uid_t uid) {
636 /* Sets (but doesn't lookup) the uid and make sure we keep the
637 * capabilities while doing so. */
639 if (context->capabilities) {
641 static const cap_value_t bits[] = {
642 CAP_SETUID, /* Necessary so that we can run setresuid() below */
643 CAP_SETPCAP /* Necessary so that we can set PR_SET_SECUREBITS later on */
646 /* First step: If we need to keep capabilities but
647 * drop privileges we need to make sure we keep our
648 * caps, whiel we drop privileges. */
650 int sb = context->secure_bits|SECURE_KEEP_CAPS;
652 if (prctl(PR_GET_SECUREBITS) != sb)
653 if (prctl(PR_SET_SECUREBITS, sb) < 0)
657 /* Second step: set the capabilities. This will reduce
658 * the capabilities to the minimum we need. */
660 if (!(d = cap_dup(context->capabilities)))
663 if (cap_set_flag(d, CAP_EFFECTIVE, ELEMENTSOF(bits), bits, CAP_SET) < 0 ||
664 cap_set_flag(d, CAP_PERMITTED, ELEMENTSOF(bits), bits, CAP_SET) < 0) {
670 if (cap_set_proc(d) < 0) {
679 /* Third step: actually set the uids */
680 if (setresuid(uid, uid, uid) < 0)
683 /* At this point we should have all necessary capabilities but
684 are otherwise a normal user. However, the caps might got
685 corrupted due to the setresuid() so we need clean them up
686 later. This is done outside of this call. */
693 static int null_conv(
695 const struct pam_message **msg,
696 struct pam_response **resp,
699 /* We don't support conversations */
704 static int setup_pam(
709 int fds[], unsigned n_fds) {
711 static const struct pam_conv conv = {
716 pam_handle_t *handle = NULL;
718 int pam_code = PAM_SUCCESS;
721 bool close_session = false;
722 pid_t pam_pid = 0, parent_pid;
728 /* We set up PAM in the parent process, then fork. The child
729 * will then stay around until killed via PR_GET_PDEATHSIG or
730 * systemd via the cgroup logic. It will then remove the PAM
731 * session again. The parent process will exec() the actual
732 * daemon. We do things this way to ensure that the main PID
733 * of the daemon is the one we initially fork()ed. */
735 if ((pam_code = pam_start(name, user, &conv, &handle)) != PAM_SUCCESS) {
741 if ((pam_code = pam_set_item(handle, PAM_TTY, tty)) != PAM_SUCCESS)
744 if ((pam_code = pam_acct_mgmt(handle, PAM_SILENT)) != PAM_SUCCESS)
747 if ((pam_code = pam_open_session(handle, PAM_SILENT)) != PAM_SUCCESS)
750 close_session = true;
752 if ((!(e = pam_getenvlist(handle)))) {
753 pam_code = PAM_BUF_ERR;
757 /* Block SIGTERM, so that we know that it won't get lost in
759 if (sigemptyset(&ss) < 0 ||
760 sigaddset(&ss, SIGTERM) < 0 ||
761 sigprocmask(SIG_BLOCK, &ss, &old_ss) < 0)
764 parent_pid = getpid();
766 if ((pam_pid = fork()) < 0)
773 /* The child's job is to reset the PAM session on
776 /* This string must fit in 10 chars (i.e. the length
777 * of "/sbin/init") */
778 rename_process("sd(PAM)");
780 /* Make sure we don't keep open the passed fds in this
781 child. We assume that otherwise only those fds are
782 open here that have been opened by PAM. */
783 close_many(fds, n_fds);
785 /* Wait until our parent died. This will most likely
786 * not work since the kernel does not allow
787 * unprivileged parents kill their privileged children
788 * this way. We rely on the control groups kill logic
789 * to do the rest for us. */
790 if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
793 /* Check if our parent process might already have
795 if (getppid() == parent_pid) {
797 if (sigwait(&ss, &sig) < 0) {
804 assert(sig == SIGTERM);
809 /* If our parent died we'll end the session */
810 if (getppid() != parent_pid)
811 if ((pam_code = pam_close_session(handle, PAM_DATA_SILENT)) != PAM_SUCCESS)
817 pam_end(handle, pam_code | PAM_DATA_SILENT);
821 /* If the child was forked off successfully it will do all the
822 * cleanups, so forget about the handle here. */
825 /* Unblock SIGTERM again in the parent */
826 if (sigprocmask(SIG_SETMASK, &old_ss, NULL) < 0)
829 /* We close the log explicitly here, since the PAM modules
830 * might have opened it, but we don't want this fd around. */
839 if (pam_code != PAM_SUCCESS)
840 err = -EPERM; /* PAM errors do not map to errno */
846 pam_code = pam_close_session(handle, PAM_DATA_SILENT);
848 pam_end(handle, pam_code | PAM_DATA_SILENT);
856 kill(pam_pid, SIGTERM);
857 kill(pam_pid, SIGCONT);
864 static int do_capability_bounding_set_drop(uint64_t drop) {
866 cap_t old_cap = NULL, new_cap = NULL;
870 /* If we are run as PID 1 we will lack CAP_SETPCAP by default
871 * in the effective set (yes, the kernel drops that when
872 * executing init!), so get it back temporarily so that we can
873 * call PR_CAPBSET_DROP. */
875 old_cap = cap_get_proc();
879 if (cap_get_flag(old_cap, CAP_SETPCAP, CAP_EFFECTIVE, &fv) < 0) {
885 static const cap_value_t v = CAP_SETPCAP;
887 new_cap = cap_dup(old_cap);
893 if (cap_set_flag(new_cap, CAP_EFFECTIVE, 1, &v, CAP_SET) < 0) {
898 if (cap_set_proc(new_cap) < 0) {
904 for (i = 0; i <= cap_last_cap(); i++)
905 if (drop & ((uint64_t) 1ULL << (uint64_t) i)) {
906 if (prctl(PR_CAPBSET_DROP, i) < 0) {
919 cap_set_proc(old_cap);
926 int exec_spawn(ExecCommand *command,
928 const ExecContext *context,
929 int fds[], unsigned n_fds,
931 bool apply_permissions,
933 bool apply_tty_stdin,
935 CGroupBonding *cgroup_bondings,
936 CGroupAttribute *cgroup_attributes,
943 char **files_env = NULL;
948 assert(fds || n_fds <= 0);
950 if (context->std_input == EXEC_INPUT_SOCKET ||
951 context->std_output == EXEC_OUTPUT_SOCKET ||
952 context->std_error == EXEC_OUTPUT_SOCKET) {
964 if ((r = exec_context_load_environment(context, &files_env)) < 0) {
965 log_error("Failed to load environment files: %s", strerror(-r));
970 argv = command->argv;
972 if (!(line = exec_command_line(argv))) {
977 log_debug("About to execute: %s", line);
980 r = cgroup_bonding_realize_list(cgroup_bondings);
984 cgroup_attribute_apply_list(cgroup_attributes, cgroup_bondings);
986 if ((pid = fork()) < 0) {
994 const char *username = NULL, *home = NULL;
995 uid_t uid = (uid_t) -1;
996 gid_t gid = (gid_t) -1;
997 char **our_env = NULL, **pam_env = NULL, **final_env = NULL, **final_argv = NULL;
999 int saved_stdout = -1, saved_stdin = -1;
1000 bool keep_stdout = false, keep_stdin = false;
1004 /* This string must fit in 10 chars (i.e. the length
1005 * of "/sbin/init") */
1006 rename_process("sd(EXEC)");
1008 /* We reset exactly these signals, since they are the
1009 * only ones we set to SIG_IGN in the main daemon. All
1010 * others we leave untouched because we set them to
1011 * SIG_DFL or a valid handler initially, both of which
1012 * will be demoted to SIG_DFL. */
1013 default_signals(SIGNALS_CRASH_HANDLER,
1014 SIGNALS_IGNORE, -1);
1016 if (sigemptyset(&ss) < 0 ||
1017 sigprocmask(SIG_SETMASK, &ss, NULL) < 0) {
1019 r = EXIT_SIGNAL_MASK;
1023 /* Close sockets very early to make sure we don't
1024 * block init reexecution because it cannot bind its
1027 err = close_all_fds(socket_fd >= 0 ? &socket_fd : fds,
1028 socket_fd >= 0 ? 1 : n_fds);
1034 if (!context->same_pgrp)
1041 if (context->tcpwrap_name) {
1043 if (!socket_tcpwrap(socket_fd, context->tcpwrap_name)) {
1049 for (i = 0; i < (int) n_fds; i++) {
1050 if (!socket_tcpwrap(fds[i], context->tcpwrap_name)) {
1058 exec_context_tty_reset(context);
1060 /* We skip the confirmation step if we shall not apply the TTY */
1061 if (confirm_spawn &&
1062 (!is_terminal_input(context->std_input) || apply_tty_stdin)) {
1065 /* Set up terminal for the question */
1066 if ((r = setup_confirm_stdio(context,
1067 &saved_stdin, &saved_stdout))) {
1072 /* Now ask the question. */
1073 if (!(line = exec_command_line(argv))) {
1079 r = ask(&response, "yns", "Execute %s? [Yes, No, Skip] ", line);
1082 if (r < 0 || response == 'n') {
1086 } else if (response == 's') {
1091 /* Release terminal for the question */
1092 if ((r = restore_confirm_stdio(context,
1093 &saved_stdin, &saved_stdout,
1094 &keep_stdin, &keep_stdout))) {
1100 /* If a socket is connected to STDIN/STDOUT/STDERR, we
1101 * must sure to drop O_NONBLOCK */
1103 fd_nonblock(socket_fd, false);
1106 err = setup_input(context, socket_fd, apply_tty_stdin);
1114 err = setup_output(context, socket_fd, file_name_from_path(command->path), apply_tty_stdin);
1121 err = setup_error(context, socket_fd, file_name_from_path(command->path), apply_tty_stdin);
1127 if (cgroup_bondings) {
1128 err = cgroup_bonding_install_list(cgroup_bondings, 0);
1135 if (context->oom_score_adjust_set) {
1138 snprintf(t, sizeof(t), "%i", context->oom_score_adjust);
1141 if (write_one_line_file("/proc/self/oom_score_adj", t) < 0) {
1142 /* Compatibility with Linux <= 2.6.35 */
1146 adj = (context->oom_score_adjust * -OOM_DISABLE) / OOM_SCORE_ADJ_MAX;
1147 adj = CLAMP(adj, OOM_DISABLE, OOM_ADJUST_MAX);
1149 snprintf(t, sizeof(t), "%i", adj);
1152 if (write_one_line_file("/proc/self/oom_adj", t) < 0
1153 && errno != EACCES) {
1155 r = EXIT_OOM_ADJUST;
1161 if (context->nice_set)
1162 if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
1168 if (context->cpu_sched_set) {
1169 struct sched_param param;
1172 param.sched_priority = context->cpu_sched_priority;
1174 if (sched_setscheduler(0, context->cpu_sched_policy |
1175 (context->cpu_sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0), ¶m) < 0) {
1177 r = EXIT_SETSCHEDULER;
1182 if (context->cpuset)
1183 if (sched_setaffinity(0, CPU_ALLOC_SIZE(context->cpuset_ncpus), context->cpuset) < 0) {
1185 r = EXIT_CPUAFFINITY;
1189 if (context->ioprio_set)
1190 if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
1196 if (context->timer_slack_nsec_set)
1197 if (prctl(PR_SET_TIMERSLACK, context->timer_slack_nsec) < 0) {
1199 r = EXIT_TIMERSLACK;
1203 if (context->utmp_id)
1204 utmp_put_init_process(context->utmp_id, getpid(), getsid(0), context->tty_path);
1206 if (context->user) {
1207 username = context->user;
1208 err = get_user_creds(&username, &uid, &gid, &home);
1214 if (is_terminal_input(context->std_input)) {
1215 err = chown_terminal(STDIN_FILENO, uid);
1222 if (cgroup_bondings && context->control_group_modify) {
1223 err = cgroup_bonding_set_group_access_list(cgroup_bondings, 0755, uid, gid);
1225 err = cgroup_bonding_set_task_access_list(cgroup_bondings, 0644, uid, gid);
1233 if (apply_permissions) {
1234 err = enforce_groups(context, username, gid);
1241 umask(context->umask);
1244 if (context->pam_name && username) {
1245 err = setup_pam(context->pam_name, username, context->tty_path, &pam_env, fds, n_fds);
1252 if (context->private_network) {
1253 if (unshare(CLONE_NEWNET) < 0) {
1262 if (strv_length(context->read_write_dirs) > 0 ||
1263 strv_length(context->read_only_dirs) > 0 ||
1264 strv_length(context->inaccessible_dirs) > 0 ||
1265 context->mount_flags != MS_SHARED ||
1266 context->private_tmp) {
1267 err = setup_namespace(context->read_write_dirs,
1268 context->read_only_dirs,
1269 context->inaccessible_dirs,
1270 context->private_tmp,
1271 context->mount_flags);
1279 if (context->root_directory)
1280 if (chroot(context->root_directory) < 0) {
1286 if (chdir(context->working_directory ? context->working_directory : "/") < 0) {
1295 if (asprintf(&d, "%s/%s",
1296 context->root_directory ? context->root_directory : "",
1297 context->working_directory ? context->working_directory : "") < 0) {
1313 /* We repeat the fd closing here, to make sure that
1314 * nothing is leaked from the PAM modules */
1315 err = close_all_fds(fds, n_fds);
1317 err = shift_fds(fds, n_fds);
1319 err = flags_fds(fds, n_fds, context->non_blocking);
1325 if (apply_permissions) {
1327 for (i = 0; i < RLIMIT_NLIMITS; i++) {
1328 if (!context->rlimit[i])
1331 if (setrlimit(i, context->rlimit[i]) < 0) {
1338 if (context->capability_bounding_set_drop) {
1339 err = do_capability_bounding_set_drop(context->capability_bounding_set_drop);
1341 r = EXIT_CAPABILITIES;
1346 if (context->user) {
1347 err = enforce_user(context, uid);
1354 /* PR_GET_SECUREBITS is not privileged, while
1355 * PR_SET_SECUREBITS is. So to suppress
1356 * potential EPERMs we'll try not to call
1357 * PR_SET_SECUREBITS unless necessary. */
1358 if (prctl(PR_GET_SECUREBITS) != context->secure_bits)
1359 if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {
1361 r = EXIT_SECUREBITS;
1365 if (context->capabilities)
1366 if (cap_set_proc(context->capabilities) < 0) {
1368 r = EXIT_CAPABILITIES;
1373 if (!(our_env = new0(char*, 7))) {
1380 if (asprintf(our_env + n_env++, "LISTEN_PID=%lu", (unsigned long) getpid()) < 0 ||
1381 asprintf(our_env + n_env++, "LISTEN_FDS=%u", n_fds) < 0) {
1388 if (asprintf(our_env + n_env++, "HOME=%s", home) < 0) {
1395 if (asprintf(our_env + n_env++, "LOGNAME=%s", username) < 0 ||
1396 asprintf(our_env + n_env++, "USER=%s", username) < 0) {
1402 if (is_terminal_input(context->std_input) ||
1403 context->std_output == EXEC_OUTPUT_TTY ||
1404 context->std_error == EXEC_OUTPUT_TTY)
1405 if (!(our_env[n_env++] = strdup(default_term_for_tty(tty_path(context))))) {
1413 if (!(final_env = strv_env_merge(
1417 context->environment,
1426 if (!(final_argv = replace_env_argv(argv, final_env))) {
1432 final_env = strv_env_clean(final_env);
1434 execve(command->path, final_argv, final_env);
1441 log_warning("Failed at step %s spawning %s: %s",
1442 exit_status_to_string(r, EXIT_STATUS_SYSTEMD),
1443 command->path, strerror(-err));
1447 strv_free(final_env);
1449 strv_free(files_env);
1450 strv_free(final_argv);
1452 if (saved_stdin >= 0)
1453 close_nointr_nofail(saved_stdin);
1455 if (saved_stdout >= 0)
1456 close_nointr_nofail(saved_stdout);
1461 strv_free(files_env);
1463 /* We add the new process to the cgroup both in the child (so
1464 * that we can be sure that no user code is ever executed
1465 * outside of the cgroup) and in the parent (so that we can be
1466 * sure that when we kill the cgroup the process will be
1468 if (cgroup_bondings)
1469 cgroup_bonding_install_list(cgroup_bondings, pid);
1471 log_debug("Forked %s as %lu", command->path, (unsigned long) pid);
1473 exec_status_start(&command->exec_status, pid);
1479 strv_free(files_env);
1484 void exec_context_init(ExecContext *c) {
1488 c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
1489 c->cpu_sched_policy = SCHED_OTHER;
1490 c->syslog_priority = LOG_DAEMON|LOG_INFO;
1491 c->syslog_level_prefix = true;
1492 c->mount_flags = MS_SHARED;
1493 c->kill_signal = SIGTERM;
1494 c->send_sigkill = true;
1497 void exec_context_done(ExecContext *c) {
1502 strv_free(c->environment);
1503 c->environment = NULL;
1505 strv_free(c->environment_files);
1506 c->environment_files = NULL;
1508 for (l = 0; l < ELEMENTSOF(c->rlimit); l++) {
1510 c->rlimit[l] = NULL;
1513 free(c->working_directory);
1514 c->working_directory = NULL;
1515 free(c->root_directory);
1516 c->root_directory = NULL;
1521 free(c->tcpwrap_name);
1522 c->tcpwrap_name = NULL;
1524 free(c->syslog_identifier);
1525 c->syslog_identifier = NULL;
1533 strv_free(c->supplementary_groups);
1534 c->supplementary_groups = NULL;
1539 if (c->capabilities) {
1540 cap_free(c->capabilities);
1541 c->capabilities = NULL;
1544 strv_free(c->read_only_dirs);
1545 c->read_only_dirs = NULL;
1547 strv_free(c->read_write_dirs);
1548 c->read_write_dirs = NULL;
1550 strv_free(c->inaccessible_dirs);
1551 c->inaccessible_dirs = NULL;
1554 CPU_FREE(c->cpuset);
1560 void exec_command_done(ExecCommand *c) {
1570 void exec_command_done_array(ExecCommand *c, unsigned n) {
1573 for (i = 0; i < n; i++)
1574 exec_command_done(c+i);
1577 void exec_command_free_list(ExecCommand *c) {
1581 LIST_REMOVE(ExecCommand, command, c, i);
1582 exec_command_done(i);
1587 void exec_command_free_array(ExecCommand **c, unsigned n) {
1590 for (i = 0; i < n; i++) {
1591 exec_command_free_list(c[i]);
1596 int exec_context_load_environment(const ExecContext *c, char ***l) {
1597 char **i, **r = NULL;
1602 STRV_FOREACH(i, c->environment_files) {
1605 bool ignore = false;
1615 if (!path_is_absolute(fn)) {
1624 if ((k = load_env_file(fn, &p)) < 0) {
1638 m = strv_env_merge(2, r, p);
1654 static void strv_fprintf(FILE *f, char **l) {
1660 fprintf(f, " %s", *g);
1663 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
1675 "%sWorkingDirectory: %s\n"
1676 "%sRootDirectory: %s\n"
1677 "%sNonBlocking: %s\n"
1678 "%sPrivateTmp: %s\n"
1679 "%sControlGroupModify: %s\n"
1680 "%sPrivateNetwork: %s\n",
1682 prefix, c->working_directory ? c->working_directory : "/",
1683 prefix, c->root_directory ? c->root_directory : "/",
1684 prefix, yes_no(c->non_blocking),
1685 prefix, yes_no(c->private_tmp),
1686 prefix, yes_no(c->control_group_modify),
1687 prefix, yes_no(c->private_network));
1689 STRV_FOREACH(e, c->environment)
1690 fprintf(f, "%sEnvironment: %s\n", prefix, *e);
1692 STRV_FOREACH(e, c->environment_files)
1693 fprintf(f, "%sEnvironmentFile: %s\n", prefix, *e);
1695 if (c->tcpwrap_name)
1697 "%sTCPWrapName: %s\n",
1698 prefix, c->tcpwrap_name);
1705 if (c->oom_score_adjust_set)
1707 "%sOOMScoreAdjust: %i\n",
1708 prefix, c->oom_score_adjust);
1710 for (i = 0; i < RLIM_NLIMITS; i++)
1712 fprintf(f, "%s%s: %llu\n", prefix, rlimit_to_string(i), (unsigned long long) c->rlimit[i]->rlim_max);
1716 "%sIOSchedulingClass: %s\n"
1717 "%sIOPriority: %i\n",
1718 prefix, ioprio_class_to_string(IOPRIO_PRIO_CLASS(c->ioprio)),
1719 prefix, (int) IOPRIO_PRIO_DATA(c->ioprio));
1721 if (c->cpu_sched_set)
1723 "%sCPUSchedulingPolicy: %s\n"
1724 "%sCPUSchedulingPriority: %i\n"
1725 "%sCPUSchedulingResetOnFork: %s\n",
1726 prefix, sched_policy_to_string(c->cpu_sched_policy),
1727 prefix, c->cpu_sched_priority,
1728 prefix, yes_no(c->cpu_sched_reset_on_fork));
1731 fprintf(f, "%sCPUAffinity:", prefix);
1732 for (i = 0; i < c->cpuset_ncpus; i++)
1733 if (CPU_ISSET_S(i, CPU_ALLOC_SIZE(c->cpuset_ncpus), c->cpuset))
1734 fprintf(f, " %i", i);
1738 if (c->timer_slack_nsec_set)
1739 fprintf(f, "%sTimerSlackNSec: %lu\n", prefix, c->timer_slack_nsec);
1742 "%sStandardInput: %s\n"
1743 "%sStandardOutput: %s\n"
1744 "%sStandardError: %s\n",
1745 prefix, exec_input_to_string(c->std_input),
1746 prefix, exec_output_to_string(c->std_output),
1747 prefix, exec_output_to_string(c->std_error));
1753 "%sTTYVHangup: %s\n"
1754 "%sTTYVTDisallocate: %s\n",
1755 prefix, c->tty_path,
1756 prefix, yes_no(c->tty_reset),
1757 prefix, yes_no(c->tty_vhangup),
1758 prefix, yes_no(c->tty_vt_disallocate));
1760 if (c->std_output == EXEC_OUTPUT_SYSLOG || c->std_output == EXEC_OUTPUT_KMSG ||
1761 c->std_output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_output == EXEC_OUTPUT_KMSG_AND_CONSOLE ||
1762 c->std_error == EXEC_OUTPUT_SYSLOG || c->std_error == EXEC_OUTPUT_KMSG ||
1763 c->std_error == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_error == EXEC_OUTPUT_KMSG_AND_CONSOLE)
1765 "%sSyslogFacility: %s\n"
1766 "%sSyslogLevel: %s\n",
1767 prefix, log_facility_unshifted_to_string(c->syslog_priority >> 3),
1768 prefix, log_level_to_string(LOG_PRI(c->syslog_priority)));
1770 if (c->capabilities) {
1772 if ((t = cap_to_text(c->capabilities, NULL))) {
1773 fprintf(f, "%sCapabilities: %s\n",
1780 fprintf(f, "%sSecure Bits:%s%s%s%s%s%s\n",
1782 (c->secure_bits & SECURE_KEEP_CAPS) ? " keep-caps" : "",
1783 (c->secure_bits & SECURE_KEEP_CAPS_LOCKED) ? " keep-caps-locked" : "",
1784 (c->secure_bits & SECURE_NO_SETUID_FIXUP) ? " no-setuid-fixup" : "",
1785 (c->secure_bits & SECURE_NO_SETUID_FIXUP_LOCKED) ? " no-setuid-fixup-locked" : "",
1786 (c->secure_bits & SECURE_NOROOT) ? " noroot" : "",
1787 (c->secure_bits & SECURE_NOROOT_LOCKED) ? "noroot-locked" : "");
1789 if (c->capability_bounding_set_drop) {
1791 fprintf(f, "%sCapabilityBoundingSet:", prefix);
1793 for (l = 0; l <= cap_last_cap(); l++)
1794 if (!(c->capability_bounding_set_drop & ((uint64_t) 1ULL << (uint64_t) l))) {
1797 if ((t = cap_to_name(l))) {
1798 fprintf(f, " %s", t);
1807 fprintf(f, "%sUser: %s\n", prefix, c->user);
1809 fprintf(f, "%sGroup: %s\n", prefix, c->group);
1811 if (strv_length(c->supplementary_groups) > 0) {
1812 fprintf(f, "%sSupplementaryGroups:", prefix);
1813 strv_fprintf(f, c->supplementary_groups);
1818 fprintf(f, "%sPAMName: %s\n", prefix, c->pam_name);
1820 if (strv_length(c->read_write_dirs) > 0) {
1821 fprintf(f, "%sReadWriteDirs:", prefix);
1822 strv_fprintf(f, c->read_write_dirs);
1826 if (strv_length(c->read_only_dirs) > 0) {
1827 fprintf(f, "%sReadOnlyDirs:", prefix);
1828 strv_fprintf(f, c->read_only_dirs);
1832 if (strv_length(c->inaccessible_dirs) > 0) {
1833 fprintf(f, "%sInaccessibleDirs:", prefix);
1834 strv_fprintf(f, c->inaccessible_dirs);
1840 "%sKillSignal: SIG%s\n"
1841 "%sSendSIGKILL: %s\n",
1842 prefix, kill_mode_to_string(c->kill_mode),
1843 prefix, signal_to_string(c->kill_signal),
1844 prefix, yes_no(c->send_sigkill));
1848 "%sUtmpIdentifier: %s\n",
1849 prefix, c->utmp_id);
1852 void exec_status_start(ExecStatus *s, pid_t pid) {
1857 dual_timestamp_get(&s->start_timestamp);
1860 void exec_status_exit(ExecStatus *s, ExecContext *context, pid_t pid, int code, int status) {
1863 if (s->pid && s->pid != pid)
1867 dual_timestamp_get(&s->exit_timestamp);
1873 if (context->utmp_id)
1874 utmp_put_dead_process(context->utmp_id, pid, code, status);
1876 exec_context_tty_reset(context);
1880 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix) {
1881 char buf[FORMAT_TIMESTAMP_MAX];
1894 prefix, (unsigned long) s->pid);
1896 if (s->start_timestamp.realtime > 0)
1898 "%sStart Timestamp: %s\n",
1899 prefix, format_timestamp(buf, sizeof(buf), s->start_timestamp.realtime));
1901 if (s->exit_timestamp.realtime > 0)
1903 "%sExit Timestamp: %s\n"
1905 "%sExit Status: %i\n",
1906 prefix, format_timestamp(buf, sizeof(buf), s->exit_timestamp.realtime),
1907 prefix, sigchld_code_to_string(s->code),
1911 char *exec_command_line(char **argv) {
1919 STRV_FOREACH(a, argv)
1922 if (!(n = new(char, k)))
1926 STRV_FOREACH(a, argv) {
1933 if (strpbrk(*a, WHITESPACE)) {
1944 /* FIXME: this doesn't really handle arguments that have
1945 * spaces and ticks in them */
1950 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
1952 const char *prefix2;
1961 p2 = strappend(prefix, "\t");
1962 prefix2 = p2 ? p2 : prefix;
1964 cmd = exec_command_line(c->argv);
1967 "%sCommand Line: %s\n",
1968 prefix, cmd ? cmd : strerror(ENOMEM));
1972 exec_status_dump(&c->exec_status, f, prefix2);
1977 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {
1983 LIST_FOREACH(command, c, c)
1984 exec_command_dump(c, f, prefix);
1987 void exec_command_append_list(ExecCommand **l, ExecCommand *e) {
1994 /* It's kind of important, that we keep the order here */
1995 LIST_FIND_TAIL(ExecCommand, command, *l, end);
1996 LIST_INSERT_AFTER(ExecCommand, command, *l, end, e);
2001 int exec_command_set(ExecCommand *c, const char *path, ...) {
2009 l = strv_new_ap(path, ap);
2015 if (!(p = strdup(path))) {
2029 static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
2030 [EXEC_INPUT_NULL] = "null",
2031 [EXEC_INPUT_TTY] = "tty",
2032 [EXEC_INPUT_TTY_FORCE] = "tty-force",
2033 [EXEC_INPUT_TTY_FAIL] = "tty-fail",
2034 [EXEC_INPUT_SOCKET] = "socket"
2037 DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput);
2039 static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
2040 [EXEC_OUTPUT_INHERIT] = "inherit",
2041 [EXEC_OUTPUT_NULL] = "null",
2042 [EXEC_OUTPUT_TTY] = "tty",
2043 [EXEC_OUTPUT_SYSLOG] = "syslog",
2044 [EXEC_OUTPUT_SYSLOG_AND_CONSOLE] = "syslog+console",
2045 [EXEC_OUTPUT_KMSG] = "kmsg",
2046 [EXEC_OUTPUT_KMSG_AND_CONSOLE] = "kmsg+console",
2047 [EXEC_OUTPUT_SOCKET] = "socket"
2050 DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);
2052 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
2053 [KILL_CONTROL_GROUP] = "control-group",
2054 [KILL_PROCESS] = "process",
2055 [KILL_NONE] = "none"
2058 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);
2060 static const char* const kill_who_table[_KILL_WHO_MAX] = {
2061 [KILL_MAIN] = "main",
2062 [KILL_CONTROL] = "control",
2066 DEFINE_STRING_TABLE_LOOKUP(kill_who, KillWho);