1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
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>
40 #include "securebits.h"
42 static int close_fds(int except[], unsigned n_except) {
47 /* Modifies the fds array! (sorts it) */
49 if (!(d = opendir("/proc/self/fd")))
52 while ((de = readdir(d))) {
55 if (de->d_name[0] == '.')
58 if ((r = safe_atoi(de->d_name, &fd)) < 0)
72 for (i = 0; i < n_except; i++)
73 if (except[i] == fd) {
82 if ((r = close_nointr(fd)) < 0)
91 static int shift_fds(int fds[], unsigned n_fds) {
92 int start, restart_from;
105 for (i = start; i < (int) n_fds; i++) {
108 /* Already at right index? */
112 if ((nfd = fcntl(fds[i], F_DUPFD, i+3)) < 0)
115 assert_se(close_nointr(fds[i]) == 0);
118 /* Hmm, the fd we wanted isn't free? Then
119 * let's remember that and try again from here*/
120 if (nfd != i+3 && restart_from < 0)
124 if (restart_from < 0)
127 start = restart_from;
133 static int flags_fds(int fds[], unsigned n_fds) {
141 /* Drops O_NONBLOCK and FD_CLOEXEC from the file flags */
143 for (i = 0; i < n_fds; i++) {
146 if ((flags = fcntl(fds[i], F_GETFL, 0)) < 0)
149 /* Since we are at it, let's make sure that nobody
150 * forgot setting O_NONBLOCK for all our fds */
152 if (fcntl(fds[i], F_SETFL, flags &~O_NONBLOCK) < 0)
155 if ((flags = fcntl(fds[i], F_GETFD, 0)) < 0)
158 /* Also make sure nobody forgot O_CLOEXEC for all our
160 if (fcntl(fds[i], F_SETFD, flags &~FD_CLOEXEC) < 0)
167 static int replace_null_fd(int fd, int flags) {
173 if ((nfd = open("/dev/null", flags|O_NOCTTY)) < 0)
177 close_nointr_nofail(nfd);
184 static int setup_output(const ExecContext *context, const char *ident) {
189 switch (context->output) {
191 case EXEC_OUTPUT_CONSOLE:
194 case EXEC_OUTPUT_NULL:
196 if ((r = replace_null_fd(STDOUT_FILENO, O_WRONLY)) < 0 ||
197 (r = replace_null_fd(STDERR_FILENO, O_WRONLY)) < 0)
202 case EXEC_OUTPUT_KERNEL:
203 case EXEC_OUTPUT_SYSLOG: {
208 struct sockaddr_un un;
211 close_nointr(STDOUT_FILENO);
212 close_nointr(STDERR_FILENO);
214 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
217 if (fd != STDOUT_FILENO) {
218 close_nointr_nofail(fd);
223 sa.sa.sa_family = AF_UNIX;
224 strncpy(sa.un.sun_path+1, LOGGER_SOCKET, sizeof(sa.un.sun_path)-1);
226 if (connect(fd, &sa.sa, sizeof(sa)) < 0) {
227 close_nointr_nofail(fd);
231 if (shutdown(fd, SHUT_RD) < 0) {
232 close_nointr_nofail(fd);
236 if ((fd = dup(fd)) < 0) {
237 close_nointr_nofail(fd);
241 if (fd != STDERR_FILENO) {
242 close_nointr_nofail(fd);
246 /* We speak a very simple protocol between log server
247 * and client: one line for the log destination (kmsg
248 * or syslog), followed by the priority field,
249 * followed by the process name. Since we replaced
250 * stdin/stderr we simple use stdio to write to
251 * it. Note that we use stderr, to minimize buffer
252 * flushing issues. */
258 context->output == EXEC_OUTPUT_KERNEL ? "kmsg" : "syslog",
259 context->syslog_priority,
260 context->syslog_identifier ? context->syslog_identifier : ident);
266 assert_not_reached("Unknown output type");
270 static int setup_input(const ExecContext *context) {
275 switch (context->input) {
277 case EXEC_INPUT_CONSOLE:
280 case EXEC_INPUT_NULL:
281 if ((r = replace_null_fd(STDIN_FILENO, O_RDONLY)) < 0)
287 assert_not_reached("Unknown input type");
291 int exec_spawn(const ExecCommand *command, const ExecContext *context, int *fds, unsigned n_fds, pid_t *ret) {
297 assert(fds || n_fds <= 0);
299 log_debug("about to execute %s", command->path);
301 if ((pid = fork()) < 0)
305 char **e, **f = NULL;
311 if (sigemptyset(&ss) < 0 ||
312 sigprocmask(SIG_SETMASK, &ss, NULL) < 0) {
313 r = EXIT_SIGNAL_MASK;
317 if (setpgid(0, 0) < 0) {
322 umask(context->umask);
324 if (setup_input(context) < 0) {
329 if (setup_output(context, file_name_from_path(command->path)) < 0) {
334 if (context->oom_adjust_set) {
337 snprintf(t, sizeof(t), "%i", context->oom_adjust);
340 if (write_one_line_file("/proc/self/oom_adj", t) < 0) {
346 if (context->root_directory)
347 if (chroot(context->root_directory) < 0) {
352 if (chdir(context->working_directory ? context->working_directory : "/") < 0) {
357 if (context->nice_set)
358 if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
363 if (context->cpu_sched_set) {
364 struct sched_param param;
367 param.sched_priority = context->cpu_sched_priority;
369 if (sched_setscheduler(0, context->cpu_sched_policy |
370 (context->cpu_sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0), ¶m) < 0) {
371 r = EXIT_SETSCHEDULER;
376 if (context->cpu_affinity_set)
377 if (sched_setaffinity(0, sizeof(context->cpu_affinity), &context->cpu_affinity) < 0) {
378 r = EXIT_CPUAFFINITY;
382 if (context->ioprio_set)
383 if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
388 if (context->timer_slack_ns_set)
389 if (prctl(PR_SET_TIMERSLACK, context->timer_slack_ns_set) < 0) {
394 if (close_fds(fds, n_fds) < 0 ||
395 shift_fds(fds, n_fds) < 0 ||
396 flags_fds(fds, n_fds) < 0) {
401 for (i = 0; i < RLIMIT_NLIMITS; i++) {
402 if (!context->rlimit[i])
405 if (setrlimit(i, context->rlimit[i]) < 0) {
411 if (context->secure_bits) {
412 if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {
420 char *listen_env[3] = {
426 snprintf(a, sizeof(a), "LISTEN_PID=%llu", (unsigned long long) getpid());
427 snprintf(b, sizeof(b), "LISTEN_FDS=%u", n_fds);
432 if (context->environment) {
433 if (!(f = strv_merge(listen_env, context->environment))) {
442 e = context->environment;
444 execve(command->path, command->argv, e);
453 log_debug("executed %s as %llu", command->path, (unsigned long long) pid);
459 void exec_context_init(ExecContext *c) {
464 c->oom_adjust_set = false;
467 c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
468 c->ioprio_set = false;
469 c->cpu_sched_policy = SCHED_OTHER;
470 c->cpu_sched_priority = 0;
471 c->cpu_sched_set = false;
472 CPU_ZERO(&c->cpu_affinity);
473 c->cpu_affinity_set = false;
477 c->syslog_priority = LOG_DAEMON|LOG_INFO;
480 c->capability_bounding_set_drop = 0;
483 void exec_context_done(ExecContext *c) {
488 strv_free(c->environment);
489 c->environment = NULL;
491 for (l = 0; l < ELEMENTSOF(c->rlimit); l++) {
496 free(c->working_directory);
497 c->working_directory = NULL;
498 free(c->root_directory);
499 c->root_directory = NULL;
501 free(c->syslog_identifier);
502 c->syslog_identifier = NULL;
510 strv_free(c->supplementary_groups);
511 c->supplementary_groups = NULL;
513 if (c->capabilities) {
514 cap_free(c->capabilities);
515 c->capabilities = NULL;
519 void exec_command_free_list(ExecCommand *c) {
523 LIST_REMOVE(ExecCommand, command, c, i);
531 void exec_command_free_array(ExecCommand **c, unsigned n) {
534 for (i = 0; i < n; i++) {
535 exec_command_free_list(c[i]);
540 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
552 "%sWorkingDirectory: %s\n"
553 "%sRootDirectory: %s\n",
555 prefix, c->working_directory ? c->working_directory : "/",
556 prefix, c->root_directory ? c->root_directory : "/");
559 for (e = c->environment; *e; e++)
560 fprintf(f, "%sEnvironment: %s\n", prefix, *e);
567 if (c->oom_adjust_set)
570 prefix, c->oom_adjust);
572 for (i = 0; i < RLIM_NLIMITS; i++)
574 fprintf(f, "%s%s: %llu\n", prefix, rlimit_to_string(i), (unsigned long long) c->rlimit[i]->rlim_max);
578 "%sIOSchedulingClass: %s\n"
579 "%sIOPriority: %i\n",
580 prefix, ioprio_class_to_string(IOPRIO_PRIO_CLASS(c->ioprio)),
581 prefix, (int) IOPRIO_PRIO_DATA(c->ioprio));
583 if (c->cpu_sched_set)
585 "%sCPUSchedulingPolicy: %s\n"
586 "%sCPUSchedulingPriority: %i\n"
587 "%sCPUSchedulingResetOnFork: %s\n",
588 prefix, sched_policy_to_string(c->cpu_sched_policy),
589 prefix, c->cpu_sched_priority,
590 prefix, yes_no(c->cpu_sched_reset_on_fork));
592 if (c->cpu_affinity_set) {
593 fprintf(f, "%sCPUAffinity:", prefix);
594 for (i = 0; i < CPU_SETSIZE; i++)
595 if (CPU_ISSET(i, &c->cpu_affinity))
596 fprintf(f, " %i", i);
600 if (c->timer_slack_ns_set)
601 fprintf(f, "%sTimerSlackNS: %lu\n", prefix, c->timer_slack_ns);
606 prefix, exec_input_to_string(c->input),
607 prefix, exec_output_to_string(c->output));
609 if (c->output == EXEC_OUTPUT_SYSLOG || c->output == EXEC_OUTPUT_KERNEL)
611 "%sSyslogFacility: %s\n"
612 "%sSyslogLevel: %s\n",
613 prefix, log_facility_to_string(LOG_FAC(c->syslog_priority)),
614 prefix, log_level_to_string(LOG_PRI(c->syslog_priority)));
616 if (c->capabilities) {
618 if ((t = cap_to_text(c->capabilities, NULL))) {
619 fprintf(f, "%sCapabilities: %s\n",
626 fprintf(f, "%sSecure Bits:%s%s%s%s%s%s\n",
628 (c->secure_bits & SECURE_KEEP_CAPS) ? " keep-caps" : "",
629 (c->secure_bits & SECURE_KEEP_CAPS_LOCKED) ? " keep-caps-locked" : "",
630 (c->secure_bits & SECURE_NO_SETUID_FIXUP) ? " no-setuid-fixup" : "",
631 (c->secure_bits & SECURE_NO_SETUID_FIXUP_LOCKED) ? " no-setuid-fixup-locked" : "",
632 (c->secure_bits & SECURE_NOROOT) ? " noroot" : "",
633 (c->secure_bits & SECURE_NOROOT_LOCKED) ? "noroot-locked" : "");
635 if (c->capability_bounding_set_drop) {
636 fprintf(f, "%sCapabilityBoundingSetDrop:", prefix);
638 for (i = 0; i <= CAP_LAST_CAP; i++)
639 if (c->capability_bounding_set_drop & (1 << i)) {
642 if ((t = cap_to_name(i))) {
643 fprintf(f, " %s", t);
652 fprintf(f, "%sUser: %s", prefix, c->user);
654 fprintf(f, "%sGroup: %s", prefix, c->group);
656 if (c->supplementary_groups) {
659 fprintf(f, "%sSupplementaryGroups:", prefix);
661 STRV_FOREACH(g, c->supplementary_groups)
662 fprintf(f, " %s", *g);
668 void exec_status_fill(ExecStatus *s, pid_t pid, int code, int status) {
674 s->timestamp = now(CLOCK_REALTIME);
677 char *exec_command_line(ExecCommand *c) {
686 STRV_FOREACH(a, c->argv)
689 if (!(n = new(char, k)))
693 STRV_FOREACH(a, c->argv) {
700 if (strpbrk(*a, WHITESPACE)) {
711 /* FIXME: this doesn't really handle arguments that have
712 * spaces and ticks in them */
717 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
726 cmd = exec_command_line(c);
729 "%sCommand Line: %s\n",
730 prefix, cmd ? cmd : strerror(ENOMEM));
735 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {
741 LIST_FOREACH(command, c, c)
742 exec_command_dump(c, f, prefix);
745 static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
746 [EXEC_OUTPUT_CONSOLE] = "console",
747 [EXEC_OUTPUT_NULL] = "null",
748 [EXEC_OUTPUT_SYSLOG] = "syslog",
749 [EXEC_OUTPUT_KERNEL] = "kernel"
752 DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);
754 static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
755 [EXEC_INPUT_NULL] = "null",
756 [EXEC_INPUT_CONSOLE] = "console"
759 DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput);