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>
48 #include "capability.h"
52 #include "securebits.h"
54 #include "namespace.h"
56 #include "exit-status.h"
58 #include "utmp-wtmp.h"
60 #include "loopback-setup.h"
62 /* This assumes there is a 'tty' group */
65 static int shift_fds(int fds[], unsigned n_fds) {
66 int start, restart_from;
71 /* Modifies the fds array! (sorts it) */
81 for (i = start; i < (int) n_fds; i++) {
84 /* Already at right index? */
88 if ((nfd = fcntl(fds[i], F_DUPFD, i+3)) < 0)
91 close_nointr_nofail(fds[i]);
94 /* Hmm, the fd we wanted isn't free? Then
95 * let's remember that and try again from here*/
96 if (nfd != i+3 && restart_from < 0)
100 if (restart_from < 0)
103 start = restart_from;
109 static int flags_fds(const int fds[], unsigned n_fds, bool nonblock) {
118 /* Drops/Sets O_NONBLOCK and FD_CLOEXEC from the file flags */
120 for (i = 0; i < n_fds; i++) {
122 if ((r = fd_nonblock(fds[i], nonblock)) < 0)
125 /* We unconditionally drop FD_CLOEXEC from the fds,
126 * since after all we want to pass these fds to our
129 if ((r = fd_cloexec(fds[i], false)) < 0)
136 static const char *tty_path(const ExecContext *context) {
139 if (context->tty_path)
140 return context->tty_path;
142 return "/dev/console";
145 void exec_context_tty_reset(const ExecContext *context) {
148 if (context->tty_vhangup)
149 terminal_vhangup(tty_path(context));
151 if (context->tty_reset)
152 reset_terminal(tty_path(context));
154 if (context->tty_vt_disallocate && context->tty_path)
155 vt_disallocate(context->tty_path);
158 static int open_null_as(int flags, int nfd) {
163 if ((fd = open("/dev/null", flags|O_NOCTTY)) < 0)
167 r = dup2(fd, nfd) < 0 ? -errno : nfd;
168 close_nointr_nofail(fd);
175 static int connect_logger_as(const ExecContext *context, ExecOutput output, const char *ident, int nfd) {
177 union sockaddr_union sa;
180 assert(output < _EXEC_OUTPUT_MAX);
184 fd = socket(AF_UNIX, SOCK_STREAM, 0);
189 sa.un.sun_family = AF_UNIX;
190 strncpy(sa.un.sun_path, "/run/systemd/journal/stdout", sizeof(sa.un.sun_path));
192 r = connect(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path));
194 close_nointr_nofail(fd);
198 if (shutdown(fd, SHUT_RD) < 0) {
199 close_nointr_nofail(fd);
210 context->syslog_identifier ? context->syslog_identifier : ident,
211 context->syslog_priority,
212 !!context->syslog_level_prefix,
213 output == EXEC_OUTPUT_SYSLOG || output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE,
214 output == EXEC_OUTPUT_KMSG || output == EXEC_OUTPUT_KMSG_AND_CONSOLE,
215 output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || output == EXEC_OUTPUT_KMSG_AND_CONSOLE || output == EXEC_OUTPUT_JOURNAL_AND_CONSOLE);
218 r = dup2(fd, nfd) < 0 ? -errno : nfd;
219 close_nointr_nofail(fd);
225 static int open_terminal_as(const char *path, mode_t mode, int nfd) {
231 if ((fd = open_terminal(path, mode | O_NOCTTY)) < 0)
235 r = dup2(fd, nfd) < 0 ? -errno : nfd;
236 close_nointr_nofail(fd);
243 static bool is_terminal_input(ExecInput i) {
245 i == EXEC_INPUT_TTY ||
246 i == EXEC_INPUT_TTY_FORCE ||
247 i == EXEC_INPUT_TTY_FAIL;
250 static int fixup_input(ExecInput std_input, int socket_fd, bool apply_tty_stdin) {
252 if (is_terminal_input(std_input) && !apply_tty_stdin)
253 return EXEC_INPUT_NULL;
255 if (std_input == EXEC_INPUT_SOCKET && socket_fd < 0)
256 return EXEC_INPUT_NULL;
261 static int fixup_output(ExecOutput std_output, int socket_fd) {
263 if (std_output == EXEC_OUTPUT_SOCKET && socket_fd < 0)
264 return EXEC_OUTPUT_INHERIT;
269 static int setup_input(const ExecContext *context, int socket_fd, bool apply_tty_stdin) {
274 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
278 case EXEC_INPUT_NULL:
279 return open_null_as(O_RDONLY, STDIN_FILENO);
282 case EXEC_INPUT_TTY_FORCE:
283 case EXEC_INPUT_TTY_FAIL: {
286 if ((fd = acquire_terminal(
288 i == EXEC_INPUT_TTY_FAIL,
289 i == EXEC_INPUT_TTY_FORCE,
293 if (fd != STDIN_FILENO) {
294 r = dup2(fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
295 close_nointr_nofail(fd);
302 case EXEC_INPUT_SOCKET:
303 return dup2(socket_fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
306 assert_not_reached("Unknown input type");
310 static int setup_output(const ExecContext *context, int socket_fd, const char *ident, bool apply_tty_stdin) {
317 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
318 o = fixup_output(context->std_output, socket_fd);
320 /* This expects the input is already set up */
324 case EXEC_OUTPUT_INHERIT:
326 /* If input got downgraded, inherit the original value */
327 if (i == EXEC_INPUT_NULL && is_terminal_input(context->std_input))
328 return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
330 /* If the input is connected to anything that's not a /dev/null, inherit that... */
331 if (i != EXEC_INPUT_NULL)
332 return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
334 /* If we are not started from PID 1 we just inherit STDOUT from our parent process. */
336 return STDOUT_FILENO;
338 /* We need to open /dev/null here anew, to get the
339 * right access mode. So we fall through */
341 case EXEC_OUTPUT_NULL:
342 return open_null_as(O_WRONLY, STDOUT_FILENO);
344 case EXEC_OUTPUT_TTY:
345 if (is_terminal_input(i))
346 return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
348 /* We don't reset the terminal if this is just about output */
349 return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
351 case EXEC_OUTPUT_SYSLOG:
352 case EXEC_OUTPUT_SYSLOG_AND_CONSOLE:
353 case EXEC_OUTPUT_KMSG:
354 case EXEC_OUTPUT_KMSG_AND_CONSOLE:
355 case EXEC_OUTPUT_JOURNAL:
356 case EXEC_OUTPUT_JOURNAL_AND_CONSOLE:
357 return connect_logger_as(context, o, ident, STDOUT_FILENO);
359 case EXEC_OUTPUT_SOCKET:
360 assert(socket_fd >= 0);
361 return dup2(socket_fd, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
364 assert_not_reached("Unknown output type");
368 static int setup_error(const ExecContext *context, int socket_fd, const char *ident, bool apply_tty_stdin) {
375 i = fixup_input(context->std_input, socket_fd, apply_tty_stdin);
376 o = fixup_output(context->std_output, socket_fd);
377 e = fixup_output(context->std_error, socket_fd);
379 /* This expects the input and output are already set up */
381 /* Don't change the stderr file descriptor if we inherit all
382 * the way and are not on a tty */
383 if (e == EXEC_OUTPUT_INHERIT &&
384 o == EXEC_OUTPUT_INHERIT &&
385 i == EXEC_INPUT_NULL &&
386 !is_terminal_input(context->std_input) &&
388 return STDERR_FILENO;
390 /* Duplicate from stdout if possible */
391 if (e == o || e == EXEC_OUTPUT_INHERIT)
392 return dup2(STDOUT_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
396 case EXEC_OUTPUT_NULL:
397 return open_null_as(O_WRONLY, STDERR_FILENO);
399 case EXEC_OUTPUT_TTY:
400 if (is_terminal_input(i))
401 return dup2(STDIN_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
403 /* We don't reset the terminal if this is just about output */
404 return open_terminal_as(tty_path(context), O_WRONLY, STDERR_FILENO);
406 case EXEC_OUTPUT_SYSLOG:
407 case EXEC_OUTPUT_SYSLOG_AND_CONSOLE:
408 case EXEC_OUTPUT_KMSG:
409 case EXEC_OUTPUT_KMSG_AND_CONSOLE:
410 case EXEC_OUTPUT_JOURNAL:
411 case EXEC_OUTPUT_JOURNAL_AND_CONSOLE:
412 return connect_logger_as(context, e, ident, STDERR_FILENO);
414 case EXEC_OUTPUT_SOCKET:
415 assert(socket_fd >= 0);
416 return dup2(socket_fd, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
419 assert_not_reached("Unknown error type");
423 static int chown_terminal(int fd, uid_t uid) {
428 /* This might fail. What matters are the results. */
429 (void) fchown(fd, uid, -1);
430 (void) fchmod(fd, TTY_MODE);
432 if (fstat(fd, &st) < 0)
435 if (st.st_uid != uid || (st.st_mode & 0777) != TTY_MODE)
441 static int setup_confirm_stdio(const ExecContext *context,
443 int *_saved_stdout) {
444 int fd = -1, saved_stdin, saved_stdout = -1, r;
447 assert(_saved_stdin);
448 assert(_saved_stdout);
450 /* This returns positive EXIT_xxx return values instead of
451 * negative errno style values! */
453 if ((saved_stdin = fcntl(STDIN_FILENO, F_DUPFD, 3)) < 0)
456 if ((saved_stdout = fcntl(STDOUT_FILENO, F_DUPFD, 3)) < 0) {
461 if ((fd = acquire_terminal(
463 context->std_input == EXEC_INPUT_TTY_FAIL,
464 context->std_input == EXEC_INPUT_TTY_FORCE,
470 if (chown_terminal(fd, getuid()) < 0) {
475 if (dup2(fd, STDIN_FILENO) < 0) {
480 if (dup2(fd, STDOUT_FILENO) < 0) {
486 close_nointr_nofail(fd);
488 *_saved_stdin = saved_stdin;
489 *_saved_stdout = saved_stdout;
494 if (saved_stdout >= 0)
495 close_nointr_nofail(saved_stdout);
497 if (saved_stdin >= 0)
498 close_nointr_nofail(saved_stdin);
501 close_nointr_nofail(fd);
506 static int restore_confirm_stdio(const ExecContext *context,
514 assert(*saved_stdin >= 0);
515 assert(saved_stdout);
516 assert(*saved_stdout >= 0);
518 /* This returns positive EXIT_xxx return values instead of
519 * negative errno style values! */
521 if (is_terminal_input(context->std_input)) {
523 /* The service wants terminal input. */
527 context->std_output == EXEC_OUTPUT_INHERIT ||
528 context->std_output == EXEC_OUTPUT_TTY;
531 /* If the service doesn't want a controlling terminal,
532 * then we need to get rid entirely of what we have
535 if (release_terminal() < 0)
538 if (dup2(*saved_stdin, STDIN_FILENO) < 0)
541 if (dup2(*saved_stdout, STDOUT_FILENO) < 0)
544 *keep_stdout = *keep_stdin = false;
550 static int enforce_groups(const ExecContext *context, const char *username, gid_t gid) {
551 bool keep_groups = false;
556 /* Lookup and set GID and supplementary group list. Here too
557 * we avoid NSS lookups for gid=0. */
559 if (context->group || username) {
561 if (context->group) {
562 const char *g = context->group;
564 if ((r = get_group_creds(&g, &gid)) < 0)
568 /* First step, initialize groups from /etc/groups */
569 if (username && gid != 0) {
570 if (initgroups(username, gid) < 0)
576 /* Second step, set our gids */
577 if (setresgid(gid, gid, gid) < 0)
581 if (context->supplementary_groups) {
586 /* Final step, initialize any manually set supplementary groups */
587 assert_se((ngroups_max = (int) sysconf(_SC_NGROUPS_MAX)) > 0);
589 if (!(gids = new(gid_t, ngroups_max)))
593 if ((k = getgroups(ngroups_max, gids)) < 0) {
600 STRV_FOREACH(i, context->supplementary_groups) {
603 if (k >= ngroups_max) {
609 r = get_group_creds(&g, gids+k);
618 if (setgroups(k, gids) < 0) {
629 static int enforce_user(const ExecContext *context, uid_t uid) {
633 /* Sets (but doesn't lookup) the uid and make sure we keep the
634 * capabilities while doing so. */
636 if (context->capabilities) {
638 static const cap_value_t bits[] = {
639 CAP_SETUID, /* Necessary so that we can run setresuid() below */
640 CAP_SETPCAP /* Necessary so that we can set PR_SET_SECUREBITS later on */
643 /* First step: If we need to keep capabilities but
644 * drop privileges we need to make sure we keep our
645 * caps, whiel we drop privileges. */
647 int sb = context->secure_bits|SECURE_KEEP_CAPS;
649 if (prctl(PR_GET_SECUREBITS) != sb)
650 if (prctl(PR_SET_SECUREBITS, sb) < 0)
654 /* Second step: set the capabilities. This will reduce
655 * the capabilities to the minimum we need. */
657 if (!(d = cap_dup(context->capabilities)))
660 if (cap_set_flag(d, CAP_EFFECTIVE, ELEMENTSOF(bits), bits, CAP_SET) < 0 ||
661 cap_set_flag(d, CAP_PERMITTED, ELEMENTSOF(bits), bits, CAP_SET) < 0) {
667 if (cap_set_proc(d) < 0) {
676 /* Third step: actually set the uids */
677 if (setresuid(uid, uid, uid) < 0)
680 /* At this point we should have all necessary capabilities but
681 are otherwise a normal user. However, the caps might got
682 corrupted due to the setresuid() so we need clean them up
683 later. This is done outside of this call. */
690 static int null_conv(
692 const struct pam_message **msg,
693 struct pam_response **resp,
696 /* We don't support conversations */
701 static int setup_pam(
706 int fds[], unsigned n_fds) {
708 static const struct pam_conv conv = {
713 pam_handle_t *handle = NULL;
715 int pam_code = PAM_SUCCESS;
718 bool close_session = false;
719 pid_t pam_pid = 0, parent_pid;
725 /* We set up PAM in the parent process, then fork. The child
726 * will then stay around until killed via PR_GET_PDEATHSIG or
727 * systemd via the cgroup logic. It will then remove the PAM
728 * session again. The parent process will exec() the actual
729 * daemon. We do things this way to ensure that the main PID
730 * of the daemon is the one we initially fork()ed. */
732 if ((pam_code = pam_start(name, user, &conv, &handle)) != PAM_SUCCESS) {
738 if ((pam_code = pam_set_item(handle, PAM_TTY, tty)) != PAM_SUCCESS)
741 if ((pam_code = pam_acct_mgmt(handle, PAM_SILENT)) != PAM_SUCCESS)
744 if ((pam_code = pam_open_session(handle, PAM_SILENT)) != PAM_SUCCESS)
747 close_session = true;
749 if ((!(e = pam_getenvlist(handle)))) {
750 pam_code = PAM_BUF_ERR;
754 /* Block SIGTERM, so that we know that it won't get lost in
756 if (sigemptyset(&ss) < 0 ||
757 sigaddset(&ss, SIGTERM) < 0 ||
758 sigprocmask(SIG_BLOCK, &ss, &old_ss) < 0)
761 parent_pid = getpid();
763 if ((pam_pid = fork()) < 0)
770 /* The child's job is to reset the PAM session on
773 /* This string must fit in 10 chars (i.e. the length
774 * of "/sbin/init"), to look pretty in /bin/ps */
775 rename_process("(sd-pam)");
777 /* Make sure we don't keep open the passed fds in this
778 child. We assume that otherwise only those fds are
779 open here that have been opened by PAM. */
780 close_many(fds, n_fds);
782 /* Wait until our parent died. This will most likely
783 * not work since the kernel does not allow
784 * unprivileged parents kill their privileged children
785 * this way. We rely on the control groups kill logic
786 * to do the rest for us. */
787 if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
790 /* Check if our parent process might already have
792 if (getppid() == parent_pid) {
794 if (sigwait(&ss, &sig) < 0) {
801 assert(sig == SIGTERM);
806 /* If our parent died we'll end the session */
807 if (getppid() != parent_pid)
808 if ((pam_code = pam_close_session(handle, PAM_DATA_SILENT)) != PAM_SUCCESS)
814 pam_end(handle, pam_code | PAM_DATA_SILENT);
818 /* If the child was forked off successfully it will do all the
819 * cleanups, so forget about the handle here. */
822 /* Unblock SIGTERM again in the parent */
823 if (sigprocmask(SIG_SETMASK, &old_ss, NULL) < 0)
826 /* We close the log explicitly here, since the PAM modules
827 * might have opened it, but we don't want this fd around. */
836 if (pam_code != PAM_SUCCESS)
837 err = -EPERM; /* PAM errors do not map to errno */
843 pam_code = pam_close_session(handle, PAM_DATA_SILENT);
845 pam_end(handle, pam_code | PAM_DATA_SILENT);
853 kill(pam_pid, SIGTERM);
854 kill(pam_pid, SIGCONT);
861 static int do_capability_bounding_set_drop(uint64_t drop) {
863 cap_t old_cap = NULL, new_cap = NULL;
867 /* If we are run as PID 1 we will lack CAP_SETPCAP by default
868 * in the effective set (yes, the kernel drops that when
869 * executing init!), so get it back temporarily so that we can
870 * call PR_CAPBSET_DROP. */
872 old_cap = cap_get_proc();
876 if (cap_get_flag(old_cap, CAP_SETPCAP, CAP_EFFECTIVE, &fv) < 0) {
882 static const cap_value_t v = CAP_SETPCAP;
884 new_cap = cap_dup(old_cap);
890 if (cap_set_flag(new_cap, CAP_EFFECTIVE, 1, &v, CAP_SET) < 0) {
895 if (cap_set_proc(new_cap) < 0) {
901 for (i = 0; i <= cap_last_cap(); i++)
902 if (drop & ((uint64_t) 1ULL << (uint64_t) i)) {
903 if (prctl(PR_CAPBSET_DROP, i) < 0) {
916 cap_set_proc(old_cap);
923 static void rename_process_from_path(const char *path) {
924 char process_name[11];
928 /* This resulting string must fit in 10 chars (i.e. the length
929 * of "/sbin/init") to look pretty in /bin/ps */
931 p = file_name_from_path(path);
933 rename_process("(...)");
939 /* The end of the process name is usually more
940 * interesting, since the first bit might just be
946 process_name[0] = '(';
947 memcpy(process_name+1, p, l);
948 process_name[1+l] = ')';
949 process_name[1+l+1] = 0;
951 rename_process(process_name);
954 int exec_spawn(ExecCommand *command,
956 const ExecContext *context,
957 int fds[], unsigned n_fds,
959 bool apply_permissions,
961 bool apply_tty_stdin,
963 CGroupBonding *cgroup_bondings,
964 CGroupAttribute *cgroup_attributes,
971 char **files_env = NULL;
976 assert(fds || n_fds <= 0);
978 if (context->std_input == EXEC_INPUT_SOCKET ||
979 context->std_output == EXEC_OUTPUT_SOCKET ||
980 context->std_error == EXEC_OUTPUT_SOCKET) {
992 if ((r = exec_context_load_environment(context, &files_env)) < 0) {
993 log_error("Failed to load environment files: %s", strerror(-r));
998 argv = command->argv;
1000 if (!(line = exec_command_line(argv))) {
1005 log_debug("About to execute: %s", line);
1008 r = cgroup_bonding_realize_list(cgroup_bondings);
1012 cgroup_attribute_apply_list(cgroup_attributes, cgroup_bondings);
1014 if ((pid = fork()) < 0) {
1022 const char *username = NULL, *home = NULL;
1023 uid_t uid = (uid_t) -1;
1024 gid_t gid = (gid_t) -1;
1025 char **our_env = NULL, **pam_env = NULL, **final_env = NULL, **final_argv = NULL;
1027 int saved_stdout = -1, saved_stdin = -1;
1028 bool keep_stdout = false, keep_stdin = false, set_access = false;
1032 rename_process_from_path(command->path);
1034 /* We reset exactly these signals, since they are the
1035 * only ones we set to SIG_IGN in the main daemon. All
1036 * others we leave untouched because we set them to
1037 * SIG_DFL or a valid handler initially, both of which
1038 * will be demoted to SIG_DFL. */
1039 default_signals(SIGNALS_CRASH_HANDLER,
1040 SIGNALS_IGNORE, -1);
1042 if (context->ignore_sigpipe)
1043 ignore_signals(SIGPIPE, -1);
1045 assert_se(sigemptyset(&ss) == 0);
1046 if (sigprocmask(SIG_SETMASK, &ss, NULL) < 0) {
1048 r = EXIT_SIGNAL_MASK;
1052 /* Close sockets very early to make sure we don't
1053 * block init reexecution because it cannot bind its
1056 err = close_all_fds(socket_fd >= 0 ? &socket_fd : fds,
1057 socket_fd >= 0 ? 1 : n_fds);
1063 if (!context->same_pgrp)
1070 if (context->tcpwrap_name) {
1072 if (!socket_tcpwrap(socket_fd, context->tcpwrap_name)) {
1078 for (i = 0; i < (int) n_fds; i++) {
1079 if (!socket_tcpwrap(fds[i], context->tcpwrap_name)) {
1087 exec_context_tty_reset(context);
1089 /* We skip the confirmation step if we shall not apply the TTY */
1090 if (confirm_spawn &&
1091 (!is_terminal_input(context->std_input) || apply_tty_stdin)) {
1094 /* Set up terminal for the question */
1095 if ((r = setup_confirm_stdio(context,
1096 &saved_stdin, &saved_stdout))) {
1101 /* Now ask the question. */
1102 if (!(line = exec_command_line(argv))) {
1108 r = ask(&response, "yns", "Execute %s? [Yes, No, Skip] ", line);
1111 if (r < 0 || response == 'n') {
1115 } else if (response == 's') {
1120 /* Release terminal for the question */
1121 if ((r = restore_confirm_stdio(context,
1122 &saved_stdin, &saved_stdout,
1123 &keep_stdin, &keep_stdout))) {
1129 /* If a socket is connected to STDIN/STDOUT/STDERR, we
1130 * must sure to drop O_NONBLOCK */
1132 fd_nonblock(socket_fd, false);
1135 err = setup_input(context, socket_fd, apply_tty_stdin);
1143 err = setup_output(context, socket_fd, file_name_from_path(command->path), apply_tty_stdin);
1150 err = setup_error(context, socket_fd, file_name_from_path(command->path), apply_tty_stdin);
1156 if (cgroup_bondings) {
1157 err = cgroup_bonding_install_list(cgroup_bondings, 0);
1164 if (context->oom_score_adjust_set) {
1167 snprintf(t, sizeof(t), "%i", context->oom_score_adjust);
1170 if (write_one_line_file("/proc/self/oom_score_adj", t) < 0) {
1171 /* Compatibility with Linux <= 2.6.35 */
1175 adj = (context->oom_score_adjust * -OOM_DISABLE) / OOM_SCORE_ADJ_MAX;
1176 adj = CLAMP(adj, OOM_DISABLE, OOM_ADJUST_MAX);
1178 snprintf(t, sizeof(t), "%i", adj);
1181 if (write_one_line_file("/proc/self/oom_adj", t) < 0
1182 && errno != EACCES) {
1184 r = EXIT_OOM_ADJUST;
1190 if (context->nice_set)
1191 if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
1197 if (context->cpu_sched_set) {
1198 struct sched_param param;
1201 param.sched_priority = context->cpu_sched_priority;
1203 if (sched_setscheduler(0, context->cpu_sched_policy |
1204 (context->cpu_sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0), ¶m) < 0) {
1206 r = EXIT_SETSCHEDULER;
1211 if (context->cpuset)
1212 if (sched_setaffinity(0, CPU_ALLOC_SIZE(context->cpuset_ncpus), context->cpuset) < 0) {
1214 r = EXIT_CPUAFFINITY;
1218 if (context->ioprio_set)
1219 if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
1225 if (context->timer_slack_nsec_set)
1226 if (prctl(PR_SET_TIMERSLACK, context->timer_slack_nsec) < 0) {
1228 r = EXIT_TIMERSLACK;
1232 if (context->utmp_id)
1233 utmp_put_init_process(context->utmp_id, getpid(), getsid(0), context->tty_path);
1235 if (context->user) {
1236 username = context->user;
1237 err = get_user_creds(&username, &uid, &gid, &home);
1243 if (is_terminal_input(context->std_input)) {
1244 err = chown_terminal(STDIN_FILENO, uid);
1251 if (cgroup_bondings && context->control_group_modify) {
1252 err = cgroup_bonding_set_group_access_list(cgroup_bondings, 0755, uid, gid);
1254 err = cgroup_bonding_set_task_access_list(cgroup_bondings, 0644, uid, gid, context->control_group_persistent);
1264 if (cgroup_bondings && !set_access && context->control_group_persistent >= 0) {
1265 err = cgroup_bonding_set_task_access_list(cgroup_bondings, (mode_t) -1, (uid_t) -1, (uid_t) -1, context->control_group_persistent);
1272 if (apply_permissions) {
1273 err = enforce_groups(context, username, gid);
1280 umask(context->umask);
1283 if (context->pam_name && username) {
1284 err = setup_pam(context->pam_name, username, context->tty_path, &pam_env, fds, n_fds);
1291 if (context->private_network) {
1292 if (unshare(CLONE_NEWNET) < 0) {
1301 if (strv_length(context->read_write_dirs) > 0 ||
1302 strv_length(context->read_only_dirs) > 0 ||
1303 strv_length(context->inaccessible_dirs) > 0 ||
1304 context->mount_flags != MS_SHARED ||
1305 context->private_tmp) {
1306 err = setup_namespace(context->read_write_dirs,
1307 context->read_only_dirs,
1308 context->inaccessible_dirs,
1309 context->private_tmp,
1310 context->mount_flags);
1318 if (context->root_directory)
1319 if (chroot(context->root_directory) < 0) {
1325 if (chdir(context->working_directory ? context->working_directory : "/") < 0) {
1334 if (asprintf(&d, "%s/%s",
1335 context->root_directory ? context->root_directory : "",
1336 context->working_directory ? context->working_directory : "") < 0) {
1352 /* We repeat the fd closing here, to make sure that
1353 * nothing is leaked from the PAM modules */
1354 err = close_all_fds(fds, n_fds);
1356 err = shift_fds(fds, n_fds);
1358 err = flags_fds(fds, n_fds, context->non_blocking);
1364 if (apply_permissions) {
1366 for (i = 0; i < RLIMIT_NLIMITS; i++) {
1367 if (!context->rlimit[i])
1370 if (setrlimit(i, context->rlimit[i]) < 0) {
1377 if (context->capability_bounding_set_drop) {
1378 err = do_capability_bounding_set_drop(context->capability_bounding_set_drop);
1380 r = EXIT_CAPABILITIES;
1385 if (context->user) {
1386 err = enforce_user(context, uid);
1393 /* PR_GET_SECUREBITS is not privileged, while
1394 * PR_SET_SECUREBITS is. So to suppress
1395 * potential EPERMs we'll try not to call
1396 * PR_SET_SECUREBITS unless necessary. */
1397 if (prctl(PR_GET_SECUREBITS) != context->secure_bits)
1398 if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {
1400 r = EXIT_SECUREBITS;
1404 if (context->capabilities)
1405 if (cap_set_proc(context->capabilities) < 0) {
1407 r = EXIT_CAPABILITIES;
1412 if (!(our_env = new0(char*, 7))) {
1419 if (asprintf(our_env + n_env++, "LISTEN_PID=%lu", (unsigned long) getpid()) < 0 ||
1420 asprintf(our_env + n_env++, "LISTEN_FDS=%u", n_fds) < 0) {
1427 if (asprintf(our_env + n_env++, "HOME=%s", home) < 0) {
1434 if (asprintf(our_env + n_env++, "LOGNAME=%s", username) < 0 ||
1435 asprintf(our_env + n_env++, "USER=%s", username) < 0) {
1441 if (is_terminal_input(context->std_input) ||
1442 context->std_output == EXEC_OUTPUT_TTY ||
1443 context->std_error == EXEC_OUTPUT_TTY)
1444 if (!(our_env[n_env++] = strdup(default_term_for_tty(tty_path(context))))) {
1452 if (!(final_env = strv_env_merge(
1456 context->environment,
1465 if (!(final_argv = replace_env_argv(argv, final_env))) {
1471 final_env = strv_env_clean(final_env);
1473 execve(command->path, final_argv, final_env);
1480 log_warning("Failed at step %s spawning %s: %s",
1481 exit_status_to_string(r, EXIT_STATUS_SYSTEMD),
1482 command->path, strerror(-err));
1486 strv_free(final_env);
1488 strv_free(files_env);
1489 strv_free(final_argv);
1491 if (saved_stdin >= 0)
1492 close_nointr_nofail(saved_stdin);
1494 if (saved_stdout >= 0)
1495 close_nointr_nofail(saved_stdout);
1500 strv_free(files_env);
1502 /* We add the new process to the cgroup both in the child (so
1503 * that we can be sure that no user code is ever executed
1504 * outside of the cgroup) and in the parent (so that we can be
1505 * sure that when we kill the cgroup the process will be
1507 if (cgroup_bondings)
1508 cgroup_bonding_install_list(cgroup_bondings, pid);
1510 log_debug("Forked %s as %lu", command->path, (unsigned long) pid);
1512 exec_status_start(&command->exec_status, pid);
1518 strv_free(files_env);
1523 void exec_context_init(ExecContext *c) {
1527 c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
1528 c->cpu_sched_policy = SCHED_OTHER;
1529 c->syslog_priority = LOG_DAEMON|LOG_INFO;
1530 c->syslog_level_prefix = true;
1531 c->mount_flags = MS_SHARED;
1532 c->kill_signal = SIGTERM;
1533 c->send_sigkill = true;
1534 c->control_group_persistent = -1;
1535 c->ignore_sigpipe = true;
1538 void exec_context_done(ExecContext *c) {
1543 strv_free(c->environment);
1544 c->environment = NULL;
1546 strv_free(c->environment_files);
1547 c->environment_files = NULL;
1549 for (l = 0; l < ELEMENTSOF(c->rlimit); l++) {
1551 c->rlimit[l] = NULL;
1554 free(c->working_directory);
1555 c->working_directory = NULL;
1556 free(c->root_directory);
1557 c->root_directory = NULL;
1562 free(c->tcpwrap_name);
1563 c->tcpwrap_name = NULL;
1565 free(c->syslog_identifier);
1566 c->syslog_identifier = NULL;
1574 strv_free(c->supplementary_groups);
1575 c->supplementary_groups = NULL;
1580 if (c->capabilities) {
1581 cap_free(c->capabilities);
1582 c->capabilities = NULL;
1585 strv_free(c->read_only_dirs);
1586 c->read_only_dirs = NULL;
1588 strv_free(c->read_write_dirs);
1589 c->read_write_dirs = NULL;
1591 strv_free(c->inaccessible_dirs);
1592 c->inaccessible_dirs = NULL;
1595 CPU_FREE(c->cpuset);
1601 void exec_command_done(ExecCommand *c) {
1611 void exec_command_done_array(ExecCommand *c, unsigned n) {
1614 for (i = 0; i < n; i++)
1615 exec_command_done(c+i);
1618 void exec_command_free_list(ExecCommand *c) {
1622 LIST_REMOVE(ExecCommand, command, c, i);
1623 exec_command_done(i);
1628 void exec_command_free_array(ExecCommand **c, unsigned n) {
1631 for (i = 0; i < n; i++) {
1632 exec_command_free_list(c[i]);
1637 int exec_context_load_environment(const ExecContext *c, char ***l) {
1638 char **i, **r = NULL;
1643 STRV_FOREACH(i, c->environment_files) {
1646 bool ignore = false;
1656 if (!path_is_absolute(fn)) {
1665 if ((k = load_env_file(fn, &p)) < 0) {
1679 m = strv_env_merge(2, r, p);
1695 static void strv_fprintf(FILE *f, char **l) {
1701 fprintf(f, " %s", *g);
1704 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
1716 "%sWorkingDirectory: %s\n"
1717 "%sRootDirectory: %s\n"
1718 "%sNonBlocking: %s\n"
1719 "%sPrivateTmp: %s\n"
1720 "%sControlGroupModify: %s\n"
1721 "%sControlGroupPersistent: %s\n"
1722 "%sPrivateNetwork: %s\n",
1724 prefix, c->working_directory ? c->working_directory : "/",
1725 prefix, c->root_directory ? c->root_directory : "/",
1726 prefix, yes_no(c->non_blocking),
1727 prefix, yes_no(c->private_tmp),
1728 prefix, yes_no(c->control_group_modify),
1729 prefix, yes_no(c->control_group_persistent),
1730 prefix, yes_no(c->private_network));
1732 STRV_FOREACH(e, c->environment)
1733 fprintf(f, "%sEnvironment: %s\n", prefix, *e);
1735 STRV_FOREACH(e, c->environment_files)
1736 fprintf(f, "%sEnvironmentFile: %s\n", prefix, *e);
1738 if (c->tcpwrap_name)
1740 "%sTCPWrapName: %s\n",
1741 prefix, c->tcpwrap_name);
1748 if (c->oom_score_adjust_set)
1750 "%sOOMScoreAdjust: %i\n",
1751 prefix, c->oom_score_adjust);
1753 for (i = 0; i < RLIM_NLIMITS; i++)
1755 fprintf(f, "%s%s: %llu\n", prefix, rlimit_to_string(i), (unsigned long long) c->rlimit[i]->rlim_max);
1759 "%sIOSchedulingClass: %s\n"
1760 "%sIOPriority: %i\n",
1761 prefix, ioprio_class_to_string(IOPRIO_PRIO_CLASS(c->ioprio)),
1762 prefix, (int) IOPRIO_PRIO_DATA(c->ioprio));
1764 if (c->cpu_sched_set)
1766 "%sCPUSchedulingPolicy: %s\n"
1767 "%sCPUSchedulingPriority: %i\n"
1768 "%sCPUSchedulingResetOnFork: %s\n",
1769 prefix, sched_policy_to_string(c->cpu_sched_policy),
1770 prefix, c->cpu_sched_priority,
1771 prefix, yes_no(c->cpu_sched_reset_on_fork));
1774 fprintf(f, "%sCPUAffinity:", prefix);
1775 for (i = 0; i < c->cpuset_ncpus; i++)
1776 if (CPU_ISSET_S(i, CPU_ALLOC_SIZE(c->cpuset_ncpus), c->cpuset))
1777 fprintf(f, " %i", i);
1781 if (c->timer_slack_nsec_set)
1782 fprintf(f, "%sTimerSlackNSec: %lu\n", prefix, c->timer_slack_nsec);
1785 "%sStandardInput: %s\n"
1786 "%sStandardOutput: %s\n"
1787 "%sStandardError: %s\n",
1788 prefix, exec_input_to_string(c->std_input),
1789 prefix, exec_output_to_string(c->std_output),
1790 prefix, exec_output_to_string(c->std_error));
1796 "%sTTYVHangup: %s\n"
1797 "%sTTYVTDisallocate: %s\n",
1798 prefix, c->tty_path,
1799 prefix, yes_no(c->tty_reset),
1800 prefix, yes_no(c->tty_vhangup),
1801 prefix, yes_no(c->tty_vt_disallocate));
1803 if (c->std_output == EXEC_OUTPUT_SYSLOG || c->std_output == EXEC_OUTPUT_KMSG || c->std_output == EXEC_OUTPUT_JOURNAL ||
1804 c->std_output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_output == EXEC_OUTPUT_KMSG_AND_CONSOLE || c->std_output == EXEC_OUTPUT_JOURNAL_AND_CONSOLE ||
1805 c->std_error == EXEC_OUTPUT_SYSLOG || c->std_error == EXEC_OUTPUT_KMSG || c->std_error == EXEC_OUTPUT_JOURNAL ||
1806 c->std_error == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_error == EXEC_OUTPUT_KMSG_AND_CONSOLE || c->std_error == EXEC_OUTPUT_JOURNAL_AND_CONSOLE)
1808 "%sSyslogFacility: %s\n"
1809 "%sSyslogLevel: %s\n",
1810 prefix, log_facility_unshifted_to_string(c->syslog_priority >> 3),
1811 prefix, log_level_to_string(LOG_PRI(c->syslog_priority)));
1813 if (c->capabilities) {
1815 if ((t = cap_to_text(c->capabilities, NULL))) {
1816 fprintf(f, "%sCapabilities: %s\n",
1823 fprintf(f, "%sSecure Bits:%s%s%s%s%s%s\n",
1825 (c->secure_bits & SECURE_KEEP_CAPS) ? " keep-caps" : "",
1826 (c->secure_bits & SECURE_KEEP_CAPS_LOCKED) ? " keep-caps-locked" : "",
1827 (c->secure_bits & SECURE_NO_SETUID_FIXUP) ? " no-setuid-fixup" : "",
1828 (c->secure_bits & SECURE_NO_SETUID_FIXUP_LOCKED) ? " no-setuid-fixup-locked" : "",
1829 (c->secure_bits & SECURE_NOROOT) ? " noroot" : "",
1830 (c->secure_bits & SECURE_NOROOT_LOCKED) ? "noroot-locked" : "");
1832 if (c->capability_bounding_set_drop) {
1834 fprintf(f, "%sCapabilityBoundingSet:", prefix);
1836 for (l = 0; l <= cap_last_cap(); l++)
1837 if (!(c->capability_bounding_set_drop & ((uint64_t) 1ULL << (uint64_t) l))) {
1840 if ((t = cap_to_name(l))) {
1841 fprintf(f, " %s", t);
1850 fprintf(f, "%sUser: %s\n", prefix, c->user);
1852 fprintf(f, "%sGroup: %s\n", prefix, c->group);
1854 if (strv_length(c->supplementary_groups) > 0) {
1855 fprintf(f, "%sSupplementaryGroups:", prefix);
1856 strv_fprintf(f, c->supplementary_groups);
1861 fprintf(f, "%sPAMName: %s\n", prefix, c->pam_name);
1863 if (strv_length(c->read_write_dirs) > 0) {
1864 fprintf(f, "%sReadWriteDirs:", prefix);
1865 strv_fprintf(f, c->read_write_dirs);
1869 if (strv_length(c->read_only_dirs) > 0) {
1870 fprintf(f, "%sReadOnlyDirs:", prefix);
1871 strv_fprintf(f, c->read_only_dirs);
1875 if (strv_length(c->inaccessible_dirs) > 0) {
1876 fprintf(f, "%sInaccessibleDirs:", prefix);
1877 strv_fprintf(f, c->inaccessible_dirs);
1883 "%sKillSignal: SIG%s\n"
1884 "%sSendSIGKILL: %s\n"
1885 "%sIgnoreSIGPIPE: %s\n",
1886 prefix, kill_mode_to_string(c->kill_mode),
1887 prefix, signal_to_string(c->kill_signal),
1888 prefix, yes_no(c->send_sigkill),
1889 prefix, yes_no(c->ignore_sigpipe));
1893 "%sUtmpIdentifier: %s\n",
1894 prefix, c->utmp_id);
1897 void exec_status_start(ExecStatus *s, pid_t pid) {
1902 dual_timestamp_get(&s->start_timestamp);
1905 void exec_status_exit(ExecStatus *s, ExecContext *context, pid_t pid, int code, int status) {
1908 if (s->pid && s->pid != pid)
1912 dual_timestamp_get(&s->exit_timestamp);
1918 if (context->utmp_id)
1919 utmp_put_dead_process(context->utmp_id, pid, code, status);
1921 exec_context_tty_reset(context);
1925 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix) {
1926 char buf[FORMAT_TIMESTAMP_MAX];
1939 prefix, (unsigned long) s->pid);
1941 if (s->start_timestamp.realtime > 0)
1943 "%sStart Timestamp: %s\n",
1944 prefix, format_timestamp(buf, sizeof(buf), s->start_timestamp.realtime));
1946 if (s->exit_timestamp.realtime > 0)
1948 "%sExit Timestamp: %s\n"
1950 "%sExit Status: %i\n",
1951 prefix, format_timestamp(buf, sizeof(buf), s->exit_timestamp.realtime),
1952 prefix, sigchld_code_to_string(s->code),
1956 char *exec_command_line(char **argv) {
1964 STRV_FOREACH(a, argv)
1967 if (!(n = new(char, k)))
1971 STRV_FOREACH(a, argv) {
1978 if (strpbrk(*a, WHITESPACE)) {
1989 /* FIXME: this doesn't really handle arguments that have
1990 * spaces and ticks in them */
1995 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
1997 const char *prefix2;
2006 p2 = strappend(prefix, "\t");
2007 prefix2 = p2 ? p2 : prefix;
2009 cmd = exec_command_line(c->argv);
2012 "%sCommand Line: %s\n",
2013 prefix, cmd ? cmd : strerror(ENOMEM));
2017 exec_status_dump(&c->exec_status, f, prefix2);
2022 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {
2028 LIST_FOREACH(command, c, c)
2029 exec_command_dump(c, f, prefix);
2032 void exec_command_append_list(ExecCommand **l, ExecCommand *e) {
2039 /* It's kind of important, that we keep the order here */
2040 LIST_FIND_TAIL(ExecCommand, command, *l, end);
2041 LIST_INSERT_AFTER(ExecCommand, command, *l, end, e);
2046 int exec_command_set(ExecCommand *c, const char *path, ...) {
2054 l = strv_new_ap(path, ap);
2060 if (!(p = strdup(path))) {
2074 static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
2075 [EXEC_INPUT_NULL] = "null",
2076 [EXEC_INPUT_TTY] = "tty",
2077 [EXEC_INPUT_TTY_FORCE] = "tty-force",
2078 [EXEC_INPUT_TTY_FAIL] = "tty-fail",
2079 [EXEC_INPUT_SOCKET] = "socket"
2082 DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput);
2084 static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
2085 [EXEC_OUTPUT_INHERIT] = "inherit",
2086 [EXEC_OUTPUT_NULL] = "null",
2087 [EXEC_OUTPUT_TTY] = "tty",
2088 [EXEC_OUTPUT_SYSLOG] = "syslog",
2089 [EXEC_OUTPUT_SYSLOG_AND_CONSOLE] = "syslog+console",
2090 [EXEC_OUTPUT_KMSG] = "kmsg",
2091 [EXEC_OUTPUT_KMSG_AND_CONSOLE] = "kmsg+console",
2092 [EXEC_OUTPUT_JOURNAL] = "journal",
2093 [EXEC_OUTPUT_JOURNAL_AND_CONSOLE] = "journal+console",
2094 [EXEC_OUTPUT_SOCKET] = "socket"
2097 DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);
2099 static const char* const kill_mode_table[_KILL_MODE_MAX] = {
2100 [KILL_CONTROL_GROUP] = "control-group",
2101 [KILL_PROCESS] = "process",
2102 [KILL_NONE] = "none"
2105 DEFINE_STRING_TABLE_LOOKUP(kill_mode, KillMode);
2107 static const char* const kill_who_table[_KILL_WHO_MAX] = {
2108 [KILL_MAIN] = "main",
2109 [KILL_CONTROL] = "control",
2113 DEFINE_STRING_TABLE_LOOKUP(kill_who, KillWho);