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;
720 bool close_session = false;
721 pid_t pam_pid = 0, parent_pid;
727 /* We set up PAM in the parent process, then fork. The child
728 * will then stay around until killed via PR_GET_PDEATHSIG or
729 * systemd via the cgroup logic. It will then remove the PAM
730 * session again. The parent process will exec() the actual
731 * daemon. We do things this way to ensure that the main PID
732 * of the daemon is the one we initially fork()ed. */
734 if ((pam_code = pam_start(name, user, &conv, &handle)) != PAM_SUCCESS) {
740 if ((pam_code = pam_set_item(handle, PAM_TTY, tty)) != PAM_SUCCESS)
743 if ((pam_code = pam_acct_mgmt(handle, PAM_SILENT)) != PAM_SUCCESS)
746 if ((pam_code = pam_open_session(handle, PAM_SILENT)) != PAM_SUCCESS)
749 close_session = true;
751 if ((!(e = pam_getenvlist(handle)))) {
752 pam_code = PAM_BUF_ERR;
756 /* Block SIGTERM, so that we know that it won't get lost in
758 if (sigemptyset(&ss) < 0 ||
759 sigaddset(&ss, SIGTERM) < 0 ||
760 sigprocmask(SIG_BLOCK, &ss, &old_ss) < 0)
763 parent_pid = getpid();
765 if ((pam_pid = fork()) < 0)
772 /* The child's job is to reset the PAM session on
775 /* This string must fit in 10 chars (i.e. the length
776 * of "/sbin/init") */
777 rename_process("sd(PAM)");
779 /* Make sure we don't keep open the passed fds in this
780 child. We assume that otherwise only those fds are
781 open here that have been opened by PAM. */
782 close_many(fds, n_fds);
784 /* Wait until our parent died. This will most likely
785 * not work since the kernel does not allow
786 * unprivileged parents kill their privileged children
787 * this way. We rely on the control groups kill logic
788 * to do the rest for us. */
789 if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
792 /* Check if our parent process might already have
794 if (getppid() == parent_pid) {
796 if (sigwait(&ss, &sig) < 0) {
803 assert(sig == SIGTERM);
808 /* If our parent died we'll end the session */
809 if (getppid() != parent_pid)
810 if ((pam_code = pam_close_session(handle, PAM_DATA_SILENT)) != PAM_SUCCESS)
816 pam_end(handle, pam_code | PAM_DATA_SILENT);
820 /* If the child was forked off successfully it will do all the
821 * cleanups, so forget about the handle here. */
824 /* Unblock SIGTERM again in the parent */
825 if (sigprocmask(SIG_SETMASK, &old_ss, NULL) < 0)
828 /* We close the log explicitly here, since the PAM modules
829 * might have opened it, but we don't want this fd around. */
840 pam_code = pam_close_session(handle, PAM_DATA_SILENT);
842 pam_end(handle, pam_code | PAM_DATA_SILENT);
850 kill(pam_pid, SIGTERM);
851 kill(pam_pid, SIGCONT);
858 static int do_capability_bounding_set_drop(uint64_t drop) {
860 cap_t old_cap = NULL, new_cap = NULL;
864 /* If we are run as PID 1 we will lack CAP_SETPCAP by default
865 * in the effective set (yes, the kernel drops that when
866 * executing init!), so get it back temporarily so that we can
867 * call PR_CAPBSET_DROP. */
869 old_cap = cap_get_proc();
873 if (cap_get_flag(old_cap, CAP_SETPCAP, CAP_EFFECTIVE, &fv) < 0) {
879 static const cap_value_t v = CAP_SETPCAP;
881 new_cap = cap_dup(old_cap);
887 if (cap_set_flag(new_cap, CAP_EFFECTIVE, 1, &v, CAP_SET) < 0) {
892 if (cap_set_proc(new_cap) < 0) {
898 for (i = 0; i <= MAX(63LU, (unsigned long) CAP_LAST_CAP); i++)
899 if (drop & ((uint64_t) 1ULL << (uint64_t) i)) {
900 if (prctl(PR_CAPBSET_DROP, i) < 0) {
916 cap_set_proc(old_cap);
923 int exec_spawn(ExecCommand *command,
925 const ExecContext *context,
926 int fds[], unsigned n_fds,
928 bool apply_permissions,
930 bool apply_tty_stdin,
932 CGroupBonding *cgroup_bondings,
933 CGroupAttribute *cgroup_attributes,
940 char **files_env = NULL;
945 assert(fds || n_fds <= 0);
947 if (context->std_input == EXEC_INPUT_SOCKET ||
948 context->std_output == EXEC_OUTPUT_SOCKET ||
949 context->std_error == EXEC_OUTPUT_SOCKET) {
961 if ((r = exec_context_load_environment(context, &files_env)) < 0) {
962 log_error("Failed to load environment files: %s", strerror(-r));
967 argv = command->argv;
969 if (!(line = exec_command_line(argv))) {
974 log_debug("About to execute: %s", line);
977 r = cgroup_bonding_realize_list(cgroup_bondings);
981 cgroup_attribute_apply_list(cgroup_attributes, cgroup_bondings);
983 if ((pid = fork()) < 0) {
991 const char *username = NULL, *home = NULL;
992 uid_t uid = (uid_t) -1;
993 gid_t gid = (gid_t) -1;
994 char **our_env = NULL, **pam_env = NULL, **final_env = NULL, **final_argv = NULL;
996 int saved_stdout = -1, saved_stdin = -1;
997 bool keep_stdout = false, keep_stdin = false;
1001 /* This string must fit in 10 chars (i.e. the length
1002 * of "/sbin/init") */
1003 rename_process("sd(EXEC)");
1005 /* We reset exactly these signals, since they are the
1006 * only ones we set to SIG_IGN in the main daemon. All
1007 * others we leave untouched because we set them to
1008 * SIG_DFL or a valid handler initially, both of which
1009 * will be demoted to SIG_DFL. */
1010 default_signals(SIGNALS_CRASH_HANDLER,
1011 SIGNALS_IGNORE, -1);
1013 if (sigemptyset(&ss) < 0 ||
1014 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
1022 if (close_all_fds(socket_fd >= 0 ? &socket_fd : fds,
1023 socket_fd >= 0 ? 1 : n_fds) < 0) {
1028 if (!context->same_pgrp)
1034 if (context->tcpwrap_name) {
1036 if (!socket_tcpwrap(socket_fd, context->tcpwrap_name)) {
1041 for (i = 0; i < (int) n_fds; i++) {
1042 if (!socket_tcpwrap(fds[i], context->tcpwrap_name)) {
1049 exec_context_tty_reset(context);
1051 /* We skip the confirmation step if we shall not apply the TTY */
1052 if (confirm_spawn &&
1053 (!is_terminal_input(context->std_input) || apply_tty_stdin)) {
1056 /* Set up terminal for the question */
1057 if ((r = setup_confirm_stdio(context,
1058 &saved_stdin, &saved_stdout)))
1061 /* Now ask the question. */
1062 if (!(line = exec_command_line(argv))) {
1067 r = ask(&response, "yns", "Execute %s? [Yes, No, Skip] ", line);
1070 if (r < 0 || response == 'n') {
1073 } else if (response == 's') {
1078 /* Release terminal for the question */
1079 if ((r = restore_confirm_stdio(context,
1080 &saved_stdin, &saved_stdout,
1081 &keep_stdin, &keep_stdout)))
1085 /* If a socket is connected to STDIN/STDOUT/STDERR, we
1086 * must sure to drop O_NONBLOCK */
1088 fd_nonblock(socket_fd, false);
1091 if (setup_input(context, socket_fd, apply_tty_stdin) < 0) {
1097 if (setup_output(context, socket_fd, file_name_from_path(command->path), apply_tty_stdin) < 0) {
1102 if (setup_error(context, socket_fd, file_name_from_path(command->path), apply_tty_stdin) < 0) {
1107 if (cgroup_bondings)
1108 if (cgroup_bonding_install_list(cgroup_bondings, 0) < 0) {
1113 if (context->oom_score_adjust_set) {
1116 snprintf(t, sizeof(t), "%i", context->oom_score_adjust);
1119 if (write_one_line_file("/proc/self/oom_score_adj", t) < 0) {
1120 /* Compatibility with Linux <= 2.6.35 */
1124 adj = (context->oom_score_adjust * -OOM_DISABLE) / OOM_SCORE_ADJ_MAX;
1125 adj = CLAMP(adj, OOM_DISABLE, OOM_ADJUST_MAX);
1127 snprintf(t, sizeof(t), "%i", adj);
1130 if (write_one_line_file("/proc/self/oom_adj", t) < 0
1131 && errno != EACCES) {
1132 r = EXIT_OOM_ADJUST;
1138 if (context->nice_set)
1139 if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
1144 if (context->cpu_sched_set) {
1145 struct sched_param param;
1148 param.sched_priority = context->cpu_sched_priority;
1150 if (sched_setscheduler(0, context->cpu_sched_policy |
1151 (context->cpu_sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0), ¶m) < 0) {
1152 r = EXIT_SETSCHEDULER;
1157 if (context->cpuset)
1158 if (sched_setaffinity(0, CPU_ALLOC_SIZE(context->cpuset_ncpus), context->cpuset) < 0) {
1159 r = EXIT_CPUAFFINITY;
1163 if (context->ioprio_set)
1164 if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
1169 if (context->timer_slack_nsec_set)
1170 if (prctl(PR_SET_TIMERSLACK, context->timer_slack_nsec) < 0) {
1171 r = EXIT_TIMERSLACK;
1175 if (context->utmp_id)
1176 utmp_put_init_process(0, context->utmp_id, getpid(), getsid(0), context->tty_path);
1178 if (context->user) {
1179 username = context->user;
1180 if (get_user_creds(&username, &uid, &gid, &home) < 0) {
1185 if (is_terminal_input(context->std_input))
1186 if (chown_terminal(STDIN_FILENO, uid) < 0) {
1191 if (cgroup_bondings && context->control_group_modify)
1192 if (cgroup_bonding_set_group_access_list(cgroup_bondings, 0755, uid, gid) < 0 ||
1193 cgroup_bonding_set_task_access_list(cgroup_bondings, 0644, uid, gid) < 0) {
1199 if (apply_permissions)
1200 if (enforce_groups(context, username, gid) < 0) {
1205 umask(context->umask);
1208 if (context->pam_name && username) {
1209 if (setup_pam(context->pam_name, username, context->tty_path, &pam_env, fds, n_fds) != 0) {
1215 if (context->private_network) {
1216 if (unshare(CLONE_NEWNET) < 0) {
1224 if (strv_length(context->read_write_dirs) > 0 ||
1225 strv_length(context->read_only_dirs) > 0 ||
1226 strv_length(context->inaccessible_dirs) > 0 ||
1227 context->mount_flags != MS_SHARED ||
1228 context->private_tmp)
1229 if ((r = setup_namespace(
1230 context->read_write_dirs,
1231 context->read_only_dirs,
1232 context->inaccessible_dirs,
1233 context->private_tmp,
1234 context->mount_flags)) < 0)
1238 if (context->root_directory)
1239 if (chroot(context->root_directory) < 0) {
1244 if (chdir(context->working_directory ? context->working_directory : "/") < 0) {
1252 if (asprintf(&d, "%s/%s",
1253 context->root_directory ? context->root_directory : "",
1254 context->working_directory ? context->working_directory : "") < 0) {
1268 /* We repeat the fd closing here, to make sure that
1269 * nothing is leaked from the PAM modules */
1270 if (close_all_fds(fds, n_fds) < 0 ||
1271 shift_fds(fds, n_fds) < 0 ||
1272 flags_fds(fds, n_fds, context->non_blocking) < 0) {
1277 if (apply_permissions) {
1279 for (i = 0; i < RLIMIT_NLIMITS; i++) {
1280 if (!context->rlimit[i])
1283 if (setrlimit(i, context->rlimit[i]) < 0) {
1289 if (context->capability_bounding_set_drop)
1290 if (do_capability_bounding_set_drop(context->capability_bounding_set_drop) < 0) {
1291 r = EXIT_CAPABILITIES;
1296 if (enforce_user(context, uid) < 0) {
1301 /* PR_GET_SECUREBITS is not privileged, while
1302 * PR_SET_SECUREBITS is. So to suppress
1303 * potential EPERMs we'll try not to call
1304 * PR_SET_SECUREBITS unless necessary. */
1305 if (prctl(PR_GET_SECUREBITS) != context->secure_bits)
1306 if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {
1307 r = EXIT_SECUREBITS;
1311 if (context->capabilities)
1312 if (cap_set_proc(context->capabilities) < 0) {
1313 r = EXIT_CAPABILITIES;
1318 if (!(our_env = new0(char*, 7))) {
1324 if (asprintf(our_env + n_env++, "LISTEN_PID=%lu", (unsigned long) getpid()) < 0 ||
1325 asprintf(our_env + n_env++, "LISTEN_FDS=%u", n_fds) < 0) {
1331 if (asprintf(our_env + n_env++, "HOME=%s", home) < 0) {
1337 if (asprintf(our_env + n_env++, "LOGNAME=%s", username) < 0 ||
1338 asprintf(our_env + n_env++, "USER=%s", username) < 0) {
1343 if (is_terminal_input(context->std_input) ||
1344 context->std_output == EXEC_OUTPUT_TTY ||
1345 context->std_error == EXEC_OUTPUT_TTY)
1346 if (!(our_env[n_env++] = strdup(default_term_for_tty(tty_path(context))))) {
1353 if (!(final_env = strv_env_merge(
1357 context->environment,
1365 if (!(final_argv = replace_env_argv(argv, final_env))) {
1370 final_env = strv_env_clean(final_env);
1372 execve(command->path, final_argv, final_env);
1377 strv_free(final_env);
1379 strv_free(files_env);
1380 strv_free(final_argv);
1382 if (saved_stdin >= 0)
1383 close_nointr_nofail(saved_stdin);
1385 if (saved_stdout >= 0)
1386 close_nointr_nofail(saved_stdout);
1391 strv_free(files_env);
1393 /* We add the new process to the cgroup both in the child (so
1394 * that we can be sure that no user code is ever executed
1395 * outside of the cgroup) and in the parent (so that we can be
1396 * sure that when we kill the cgroup the process will be
1398 if (cgroup_bondings)
1399 cgroup_bonding_install_list(cgroup_bondings, pid);
1401 log_debug("Forked %s as %lu", command->path, (unsigned long) pid);
1403 exec_status_start(&command->exec_status, pid);
1409 strv_free(files_env);
1414 void exec_context_init(ExecContext *c) {
1418 c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
1419 c->cpu_sched_policy = SCHED_OTHER;
1420 c->syslog_priority = LOG_DAEMON|LOG_INFO;
1421 c->syslog_level_prefix = true;
1422 c->mount_flags = MS_SHARED;
1423 c->kill_signal = SIGTERM;
1424 c->send_sigkill = true;
1427 void exec_context_done(ExecContext *c) {
1432 strv_free(c->environment);
1433 c->environment = NULL;
1435 strv_free(c->environment_files);
1436 c->environment_files = NULL;
1438 for (l = 0; l < ELEMENTSOF(c->rlimit); l++) {
1440 c->rlimit[l] = NULL;
1443 free(c->working_directory);
1444 c->working_directory = NULL;
1445 free(c->root_directory);
1446 c->root_directory = NULL;
1451 free(c->tcpwrap_name);
1452 c->tcpwrap_name = NULL;
1454 free(c->syslog_identifier);
1455 c->syslog_identifier = NULL;
1463 strv_free(c->supplementary_groups);
1464 c->supplementary_groups = NULL;
1469 if (c->capabilities) {
1470 cap_free(c->capabilities);
1471 c->capabilities = NULL;
1474 strv_free(c->read_only_dirs);
1475 c->read_only_dirs = NULL;
1477 strv_free(c->read_write_dirs);
1478 c->read_write_dirs = NULL;
1480 strv_free(c->inaccessible_dirs);
1481 c->inaccessible_dirs = NULL;
1484 CPU_FREE(c->cpuset);
1490 void exec_command_done(ExecCommand *c) {
1500 void exec_command_done_array(ExecCommand *c, unsigned n) {
1503 for (i = 0; i < n; i++)
1504 exec_command_done(c+i);
1507 void exec_command_free_list(ExecCommand *c) {
1511 LIST_REMOVE(ExecCommand, command, c, i);
1512 exec_command_done(i);
1517 void exec_command_free_array(ExecCommand **c, unsigned n) {
1520 for (i = 0; i < n; i++) {
1521 exec_command_free_list(c[i]);
1526 int exec_context_load_environment(const ExecContext *c, char ***l) {
1527 char **i, **r = NULL;
1532 STRV_FOREACH(i, c->environment_files) {
1535 bool ignore = false;
1545 if (!path_is_absolute(fn)) {
1554 if ((k = load_env_file(fn, &p)) < 0) {
1568 m = strv_env_merge(2, r, p);
1584 static void strv_fprintf(FILE *f, char **l) {
1590 fprintf(f, " %s", *g);
1593 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
1605 "%sWorkingDirectory: %s\n"
1606 "%sRootDirectory: %s\n"
1607 "%sNonBlocking: %s\n"
1608 "%sPrivateTmp: %s\n"
1609 "%sControlGroupModify: %s\n"
1610 "%sPrivateNetwork: %s\n",
1612 prefix, c->working_directory ? c->working_directory : "/",
1613 prefix, c->root_directory ? c->root_directory : "/",
1614 prefix, yes_no(c->non_blocking),
1615 prefix, yes_no(c->private_tmp),
1616 prefix, yes_no(c->control_group_modify),
1617 prefix, yes_no(c->private_network));
1619 STRV_FOREACH(e, c->environment)
1620 fprintf(f, "%sEnvironment: %s\n", prefix, *e);
1622 STRV_FOREACH(e, c->environment_files)
1623 fprintf(f, "%sEnvironmentFile: %s\n", prefix, *e);
1625 if (c->tcpwrap_name)
1627 "%sTCPWrapName: %s\n",
1628 prefix, c->tcpwrap_name);
1635 if (c->oom_score_adjust_set)
1637 "%sOOMScoreAdjust: %i\n",
1638 prefix, c->oom_score_adjust);
1640 for (i = 0; i < RLIM_NLIMITS; i++)
1642 fprintf(f, "%s%s: %llu\n", prefix, rlimit_to_string(i), (unsigned long long) c->rlimit[i]->rlim_max);
1646 "%sIOSchedulingClass: %s\n"
1647 "%sIOPriority: %i\n",
1648 prefix, ioprio_class_to_string(IOPRIO_PRIO_CLASS(c->ioprio)),
1649 prefix, (int) IOPRIO_PRIO_DATA(c->ioprio));
1651 if (c->cpu_sched_set)
1653 "%sCPUSchedulingPolicy: %s\n"
1654 "%sCPUSchedulingPriority: %i\n"
1655 "%sCPUSchedulingResetOnFork: %s\n",
1656 prefix, sched_policy_to_string(c->cpu_sched_policy),
1657 prefix, c->cpu_sched_priority,
1658 prefix, yes_no(c->cpu_sched_reset_on_fork));
1661 fprintf(f, "%sCPUAffinity:", prefix);
1662 for (i = 0; i < c->cpuset_ncpus; i++)
1663 if (CPU_ISSET_S(i, CPU_ALLOC_SIZE(c->cpuset_ncpus), c->cpuset))
1664 fprintf(f, " %i", i);
1668 if (c->timer_slack_nsec_set)
1669 fprintf(f, "%sTimerSlackNSec: %lu\n", prefix, c->timer_slack_nsec);
1672 "%sStandardInput: %s\n"
1673 "%sStandardOutput: %s\n"
1674 "%sStandardError: %s\n",
1675 prefix, exec_input_to_string(c->std_input),
1676 prefix, exec_output_to_string(c->std_output),
1677 prefix, exec_output_to_string(c->std_error));
1683 "%sTTYVHangup: %s\n"
1684 "%sTTYVTDisallocate: %s\n",
1685 prefix, c->tty_path,
1686 prefix, yes_no(c->tty_reset),
1687 prefix, yes_no(c->tty_vhangup),
1688 prefix, yes_no(c->tty_vt_disallocate));
1690 if (c->std_output == EXEC_OUTPUT_SYSLOG || c->std_output == EXEC_OUTPUT_KMSG ||
1691 c->std_output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_output == EXEC_OUTPUT_KMSG_AND_CONSOLE ||
1692 c->std_error == EXEC_OUTPUT_SYSLOG || c->std_error == EXEC_OUTPUT_KMSG ||
1693 c->std_error == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_error == EXEC_OUTPUT_KMSG_AND_CONSOLE)
1695 "%sSyslogFacility: %s\n"
1696 "%sSyslogLevel: %s\n",
1697 prefix, log_facility_unshifted_to_string(c->syslog_priority >> 3),
1698 prefix, log_level_to_string(LOG_PRI(c->syslog_priority)));
1700 if (c->capabilities) {
1702 if ((t = cap_to_text(c->capabilities, NULL))) {
1703 fprintf(f, "%sCapabilities: %s\n",
1710 fprintf(f, "%sSecure Bits:%s%s%s%s%s%s\n",
1712 (c->secure_bits & SECURE_KEEP_CAPS) ? " keep-caps" : "",
1713 (c->secure_bits & SECURE_KEEP_CAPS_LOCKED) ? " keep-caps-locked" : "",
1714 (c->secure_bits & SECURE_NO_SETUID_FIXUP) ? " no-setuid-fixup" : "",
1715 (c->secure_bits & SECURE_NO_SETUID_FIXUP_LOCKED) ? " no-setuid-fixup-locked" : "",
1716 (c->secure_bits & SECURE_NOROOT) ? " noroot" : "",
1717 (c->secure_bits & SECURE_NOROOT_LOCKED) ? "noroot-locked" : "");
1719 if (c->capability_bounding_set_drop) {
1721 fprintf(f, "%sCapabilityBoundingSet:", prefix);
1723 for (l = 0; l <= (unsigned long) CAP_LAST_CAP; l++)
1724 if (!(c->capability_bounding_set_drop & ((uint64_t) 1ULL << (uint64_t) l))) {
1727 if ((t = cap_to_name(l))) {
1728 fprintf(f, " %s", t);
1737 fprintf(f, "%sUser: %s\n", prefix, c->user);
1739 fprintf(f, "%sGroup: %s\n", prefix, c->group);
1741 if (strv_length(c->supplementary_groups) > 0) {
1742 fprintf(f, "%sSupplementaryGroups:", prefix);
1743 strv_fprintf(f, c->supplementary_groups);
1748 fprintf(f, "%sPAMName: %s\n", prefix, c->pam_name);
1750 if (strv_length(c->read_write_dirs) > 0) {
1751 fprintf(f, "%sReadWriteDirs:", prefix);
1752 strv_fprintf(f, c->read_write_dirs);
1756 if (strv_length(c->read_only_dirs) > 0) {
1757 fprintf(f, "%sReadOnlyDirs:", prefix);
1758 strv_fprintf(f, c->read_only_dirs);
1762 if (strv_length(c->inaccessible_dirs) > 0) {
1763 fprintf(f, "%sInaccessibleDirs:", prefix);
1764 strv_fprintf(f, c->inaccessible_dirs);
1770 "%sKillSignal: SIG%s\n"
1771 "%sSendSIGKILL: %s\n",
1772 prefix, kill_mode_to_string(c->kill_mode),
1773 prefix, signal_to_string(c->kill_signal),
1774 prefix, yes_no(c->send_sigkill));
1778 "%sUtmpIdentifier: %s\n",
1779 prefix, c->utmp_id);
1782 void exec_status_start(ExecStatus *s, pid_t pid) {
1787 dual_timestamp_get(&s->start_timestamp);
1790 void exec_status_exit(ExecStatus *s, ExecContext *context, pid_t pid, int code, int status) {
1793 if ((s->pid && s->pid != pid) ||
1794 !s->start_timestamp.realtime <= 0)
1798 dual_timestamp_get(&s->exit_timestamp);
1804 if (context->utmp_id)
1805 utmp_put_dead_process(context->utmp_id, pid, code, status);
1807 exec_context_tty_reset(context);
1811 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix) {
1812 char buf[FORMAT_TIMESTAMP_MAX];
1825 prefix, (unsigned long) s->pid);
1827 if (s->start_timestamp.realtime > 0)
1829 "%sStart Timestamp: %s\n",
1830 prefix, format_timestamp(buf, sizeof(buf), s->start_timestamp.realtime));
1832 if (s->exit_timestamp.realtime > 0)
1834 "%sExit Timestamp: %s\n"
1836 "%sExit Status: %i\n",
1837 prefix, format_timestamp(buf, sizeof(buf), s->exit_timestamp.realtime),
1838 prefix, sigchld_code_to_string(s->code),
1842 char *exec_command_line(char **argv) {
1850 STRV_FOREACH(a, argv)
1853 if (!(n = new(char, k)))
1857 STRV_FOREACH(a, argv) {
1864 if (strpbrk(*a, WHITESPACE)) {
1875 /* FIXME: this doesn't really handle arguments that have
1876 * spaces and ticks in them */
1881 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
1883 const char *prefix2;
1892 p2 = strappend(prefix, "\t");
1893 prefix2 = p2 ? p2 : prefix;
1895 cmd = exec_command_line(c->argv);
1898 "%sCommand Line: %s\n",
1899 prefix, cmd ? cmd : strerror(ENOMEM));
1903 exec_status_dump(&c->exec_status, f, prefix2);
1908 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {
1914 LIST_FOREACH(command, c, c)
1915 exec_command_dump(c, f, prefix);
1918 void exec_command_append_list(ExecCommand **l, ExecCommand *e) {
1925 /* It's kind of important, that we keep the order here */
1926 LIST_FIND_TAIL(ExecCommand, command, *l, end);
1927 LIST_INSERT_AFTER(ExecCommand, command, *l, end, e);
1932 int exec_command_set(ExecCommand *c, const char *path, ...) {
1940 l = strv_new_ap(path, ap);
1946 if (!(p = strdup(path))) {
1960 static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
1961 [EXEC_INPUT_NULL] = "null",
1962 [EXEC_INPUT_TTY] = "tty",
1963 [EXEC_INPUT_TTY_FORCE] = "tty-force",
1964 [EXEC_INPUT_TTY_FAIL] = "tty-fail",
1965 [EXEC_INPUT_SOCKET] = "socket"
1968 DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput);
1970 static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
1971 [EXEC_OUTPUT_INHERIT] = "inherit",
1972 [EXEC_OUTPUT_NULL] = "null",
1973 [EXEC_OUTPUT_TTY] = "tty",
1974 [EXEC_OUTPUT_SYSLOG] = "syslog",
1975 [EXEC_OUTPUT_SYSLOG_AND_CONSOLE] = "syslog+console",
1976 [EXEC_OUTPUT_KMSG] = "kmsg",
1977 [EXEC_OUTPUT_KMSG_AND_CONSOLE] = "kmsg+console",
1978 [EXEC_OUTPUT_SOCKET] = "socket"
1981 DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);
1983 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
1984 [KILL_CONTROL_GROUP] = "control-group",
1985 [KILL_PROCESS] = "process",
1986 [KILL_NONE] = "none"
1989 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);
1991 static const char* const kill_who_table[_KILL_WHO_MAX] = {
1992 [KILL_MAIN] = "main",
1993 [KILL_CONTROL] = "control",
1997 DEFINE_STRING_TABLE_LOOKUP(kill_who, KillWho);