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/>.
22 #pragma GCC diagnostic ignored "-Wattributes"
31 #include <sys/socket.h>
33 #include <sys/prctl.h>
34 #include <linux/sched.h>
42 #include "securebits.h"
44 static int close_fds(int except
[], unsigned n_except
) {
49 /* Modifies the fds array! (sorts it) */
51 if (!(d
= opendir("/proc/self/fd")))
54 while ((de
= readdir(d
))) {
57 if (de
->d_name
[0] == '.')
60 if ((r
= safe_atoi(de
->d_name
, &fd
)) < 0)
74 for (i
= 0; i
< n_except
; i
++)
75 if (except
[i
] == fd
) {
84 if ((r
= close_nointr(fd
)) < 0)
93 static int shift_fds(int fds
[], unsigned n_fds
) {
94 int start
, restart_from
;
107 for (i
= start
; i
< (int) n_fds
; i
++) {
110 /* Already at right index? */
114 if ((nfd
= fcntl(fds
[i
], F_DUPFD
, i
+3)) < 0)
117 assert_se(close_nointr(fds
[i
]) == 0);
120 /* Hmm, the fd we wanted isn't free? Then
121 * let's remember that and try again from here*/
122 if (nfd
!= i
+3 && restart_from
< 0)
126 if (restart_from
< 0)
129 start
= restart_from
;
135 static int flags_fds(int fds
[], unsigned n_fds
) {
143 /* Drops O_NONBLOCK and FD_CLOEXEC from the file flags */
145 for (i
= 0; i
< n_fds
; i
++) {
148 if ((flags
= fcntl(fds
[i
], F_GETFL
, 0)) < 0)
151 /* Since we are at it, let's make sure that nobody
152 * forgot setting O_NONBLOCK for all our fds */
154 if (fcntl(fds
[i
], F_SETFL
, flags
&~O_NONBLOCK
) < 0)
157 if ((flags
= fcntl(fds
[i
], F_GETFD
, 0)) < 0)
160 /* Also make sure nobody forgot O_CLOEXEC for all our
162 if (fcntl(fds
[i
], F_SETFD
, flags
&~FD_CLOEXEC
) < 0)
169 static int replace_null_fd(int fd
, int flags
) {
175 if ((nfd
= open("/dev/null", flags
|O_NOCTTY
)) < 0)
179 close_nointr_nofail(nfd
);
186 static int setup_output(const ExecContext
*context
, const char *ident
) {
191 switch (context
->output
) {
193 case EXEC_OUTPUT_CONSOLE
:
196 case EXEC_OUTPUT_NULL
:
198 if ((r
= replace_null_fd(STDOUT_FILENO
, O_WRONLY
)) < 0 ||
199 (r
= replace_null_fd(STDERR_FILENO
, O_WRONLY
)) < 0)
204 case EXEC_OUTPUT_KERNEL
:
205 case EXEC_OUTPUT_SYSLOG
: {
210 struct sockaddr_un un
;
213 close_nointr(STDOUT_FILENO
);
214 close_nointr(STDERR_FILENO
);
216 if ((fd
= socket(AF_UNIX
, SOCK_STREAM
, 0)) < 0)
219 if (fd
!= STDOUT_FILENO
) {
220 close_nointr_nofail(fd
);
225 sa
.sa
.sa_family
= AF_UNIX
;
226 strncpy(sa
.un
.sun_path
+1, LOGGER_SOCKET
, sizeof(sa
.un
.sun_path
)-1);
228 if (connect(fd
, &sa
.sa
, sizeof(sa
)) < 0) {
229 close_nointr_nofail(fd
);
233 if (shutdown(fd
, SHUT_RD
) < 0) {
234 close_nointr_nofail(fd
);
238 if ((fd
= dup(fd
)) < 0) {
239 close_nointr_nofail(fd
);
243 if (fd
!= STDERR_FILENO
) {
244 close_nointr_nofail(fd
);
248 /* We speak a very simple protocol between log server
249 * and client: one line for the log destination (kmsg
250 * or syslog), followed by the priority field,
251 * followed by the process name. Since we replaced
252 * stdin/stderr we simple use stdio to write to
253 * it. Note that we use stderr, to minimize buffer
254 * flushing issues. */
260 context
->output
== EXEC_OUTPUT_KERNEL
? "kmsg" : "syslog",
261 context
->syslog_priority
,
262 context
->syslog_identifier
? context
->syslog_identifier
: ident
);
268 assert_not_reached("Unknown output type");
272 int setup_input(const ExecContext
*context
) {
277 switch (context
->input
) {
279 case EXEC_INPUT_CONSOLE
:
282 case EXEC_INPUT_NULL
:
283 if ((r
= replace_null_fd(STDIN_FILENO
, O_RDONLY
)) < 0)
289 assert_not_reached("Unknown input type");
293 int exec_spawn(const ExecCommand
*command
, const ExecContext
*context
, int *fds
, unsigned n_fds
, pid_t
*ret
) {
299 assert(fds
|| n_fds
<= 0);
301 log_debug("about to execute %s", command
->path
);
303 if ((pid
= fork()) < 0)
307 char **e
, **f
= NULL
;
313 if (sigemptyset(&ss
) < 0 ||
314 sigprocmask(SIG_SETMASK
, &ss
, NULL
) < 0) {
315 r
= EXIT_SIGNAL_MASK
;
319 if (setpgid(0, 0) < 0) {
324 umask(context
->umask
);
326 if (setup_input(context
) < 0) {
331 if (setup_output(context
, file_name_from_path(command
->path
)) < 0) {
336 if (context
->oom_adjust_set
) {
339 snprintf(t
, sizeof(t
), "%i", context
->oom_adjust
);
342 if (write_one_line_file("/proc/self/oom_adj", t
) < 0) {
348 if (context
->root_directory
)
349 if (chroot(context
->root_directory
) < 0) {
354 if (chdir(context
->working_directory
? context
->working_directory
: "/") < 0) {
359 if (context
->nice_set
)
360 if (setpriority(PRIO_PROCESS
, 0, context
->nice
) < 0) {
365 if (context
->cpu_sched_set
) {
366 struct sched_param param
;
369 param
.sched_priority
= context
->cpu_sched_priority
;
371 if (sched_setscheduler(0, context
->cpu_sched_policy
|
372 (context
->cpu_sched_reset_on_fork
? SCHED_RESET_ON_FORK
: 0), ¶m
) < 0) {
373 r
= EXIT_SETSCHEDULER
;
378 if (context
->cpu_affinity_set
)
379 if (sched_setaffinity(0, sizeof(context
->cpu_affinity
), &context
->cpu_affinity
) < 0) {
380 r
= EXIT_CPUAFFINITY
;
384 if (context
->ioprio_set
)
385 if (ioprio_set(IOPRIO_WHO_PROCESS
, 0, context
->ioprio
) < 0) {
390 if (context
->timer_slack_ns_set
)
391 if (prctl(PR_SET_TIMERSLACK
, context
->timer_slack_ns_set
) < 0) {
396 if (close_fds(fds
, n_fds
) < 0 ||
397 shift_fds(fds
, n_fds
) < 0 ||
398 flags_fds(fds
, n_fds
) < 0) {
403 for (i
= 0; i
< RLIMIT_NLIMITS
; i
++) {
404 if (!context
->rlimit
[i
])
407 if (setrlimit(i
, context
->rlimit
[i
]) < 0) {
413 if (context
->secure_bits
) {
414 if (prctl(PR_SET_SECUREBITS
, context
->secure_bits
) < 0) {
422 char *listen_env
[3] = {
428 snprintf(a
, sizeof(a
), "LISTEN_PID=%llu", (unsigned long long) getpid());
429 snprintf(b
, sizeof(b
), "LISTEN_FDS=%u", n_fds
);
434 if (context
->environment
) {
435 if (!(f
= strv_merge(listen_env
, context
->environment
))) {
444 e
= context
->environment
;
446 execve(command
->path
, command
->argv
, e
);
455 log_debug("executed %s as %llu", command
->path
, (unsigned long long) pid
);
461 void exec_context_init(ExecContext
*c
) {
466 c
->oom_adjust_set
= false;
469 c
->ioprio
= IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE
, 0);
470 c
->ioprio_set
= false;
471 c
->cpu_sched_policy
= SCHED_OTHER
;
472 c
->cpu_sched_priority
= 0;
473 c
->cpu_sched_set
= false;
474 CPU_ZERO(&c
->cpu_affinity
);
475 c
->cpu_affinity_set
= false;
479 c
->syslog_priority
= LOG_DAEMON
|LOG_INFO
;
482 c
->capability_bounding_set_drop
= 0;
485 void exec_context_done(ExecContext
*c
) {
490 strv_free(c
->environment
);
491 c
->environment
= NULL
;
493 for (l
= 0; l
< ELEMENTSOF(c
->rlimit
); l
++) {
498 free(c
->working_directory
);
499 c
->working_directory
= NULL
;
500 free(c
->root_directory
);
501 c
->root_directory
= NULL
;
503 free(c
->syslog_identifier
);
504 c
->syslog_identifier
= NULL
;
512 strv_free(c
->supplementary_groups
);
513 c
->supplementary_groups
= NULL
;
515 if (c
->capabilities
) {
516 cap_free(c
->capabilities
);
517 c
->capabilities
= NULL
;
521 void exec_command_free_list(ExecCommand
*c
) {
525 LIST_REMOVE(ExecCommand
, command
, c
, i
);
533 void exec_command_free_array(ExecCommand
**c
, unsigned n
) {
536 for (i
= 0; i
< n
; i
++) {
537 exec_command_free_list(c
[i
]);
542 void exec_context_dump(ExecContext
*c
, FILE* f
, const char *prefix
) {
554 "%sWorkingDirectory: %s\n"
555 "%sRootDirectory: %s\n",
557 prefix
, c
->working_directory
? c
->working_directory
: "/",
558 prefix
, c
->root_directory
? c
->root_directory
: "/");
561 for (e
= c
->environment
; *e
; e
++)
562 fprintf(f
, "%sEnvironment: %s\n", prefix
, *e
);
569 if (c
->oom_adjust_set
)
572 prefix
, c
->oom_adjust
);
574 for (i
= 0; i
< RLIM_NLIMITS
; i
++)
576 fprintf(f
, "%s%s: %llu\n", prefix
, rlimit_to_string(i
), (unsigned long long) c
->rlimit
[i
]->rlim_max
);
580 "%sIOSchedulingClass: %s\n"
581 "%sIOPriority: %i\n",
582 prefix
, ioprio_class_to_string(IOPRIO_PRIO_CLASS(c
->ioprio
)),
583 prefix
, (int) IOPRIO_PRIO_DATA(c
->ioprio
));
585 if (c
->cpu_sched_set
)
587 "%sCPUSchedulingPolicy: %s\n"
588 "%sCPUSchedulingPriority: %i\n"
589 "%sCPUSchedulingResetOnFork: %s\n",
590 prefix
, sched_policy_to_string(c
->cpu_sched_policy
),
591 prefix
, c
->cpu_sched_priority
,
592 prefix
, yes_no(c
->cpu_sched_reset_on_fork
));
594 if (c
->cpu_affinity_set
) {
595 fprintf(f
, "%sCPUAffinity:", prefix
);
596 for (i
= 0; i
< CPU_SETSIZE
; i
++)
597 if (CPU_ISSET(i
, &c
->cpu_affinity
))
598 fprintf(f
, " %i", i
);
602 if (c
->timer_slack_ns_set
)
603 fprintf(f
, "%sTimerSlackNS: %lu\n", prefix
, c
->timer_slack_ns
);
608 prefix
, exec_input_to_string(c
->input
),
609 prefix
, exec_output_to_string(c
->output
));
611 if (c
->output
== EXEC_OUTPUT_SYSLOG
|| c
->output
== EXEC_OUTPUT_KERNEL
)
613 "%sSyslogFacility: %s\n"
614 "%sSyslogLevel: %s\n",
615 prefix
, log_facility_to_string(LOG_FAC(c
->syslog_priority
)),
616 prefix
, log_level_to_string(LOG_PRI(c
->syslog_priority
)));
618 if (c
->capabilities
) {
620 if ((t
= cap_to_text(c
->capabilities
, NULL
))) {
621 fprintf(f
, "%sCapabilities: %s\n",
628 fprintf(f
, "%sSecure Bits:%s%s%s%s%s%s\n",
630 (c
->secure_bits
& SECURE_KEEP_CAPS
) ? " keep-caps" : "",
631 (c
->secure_bits
& SECURE_KEEP_CAPS_LOCKED
) ? " keep-caps-locked" : "",
632 (c
->secure_bits
& SECURE_NO_SETUID_FIXUP
) ? " no-setuid-fixup" : "",
633 (c
->secure_bits
& SECURE_NO_SETUID_FIXUP_LOCKED
) ? " no-setuid-fixup-locked" : "",
634 (c
->secure_bits
& SECURE_NOROOT
) ? " noroot" : "",
635 (c
->secure_bits
& SECURE_NOROOT_LOCKED
) ? "noroot-locked" : "");
637 if (c
->capability_bounding_set_drop
) {
638 fprintf(f
, "%sCapabilityBoundingSetDrop:", prefix
);
640 for (i
= 0; i
<= CAP_LAST_CAP
; i
++)
641 if (c
->capability_bounding_set_drop
& (1 << i
)) {
644 if ((t
= cap_to_name(i
))) {
645 fprintf(f
, " %s", t
);
654 fprintf(f
, "%sUser: %s", prefix
, c
->user
);
656 fprintf(f
, "%sGroup: %s", prefix
, c
->group
);
658 if (c
->supplementary_groups
) {
661 fprintf(f
, "%sSupplementaryGroups:", prefix
);
663 STRV_FOREACH(g
, c
->supplementary_groups
)
664 fprintf(f
, " %s", *g
);
670 void exec_status_fill(ExecStatus
*s
, pid_t pid
, int code
, int status
) {
676 s
->timestamp
= now(CLOCK_REALTIME
);
679 char *exec_command_line(ExecCommand
*c
) {
688 STRV_FOREACH(a
, c
->argv
)
691 if (!(n
= new(char, k
)))
695 STRV_FOREACH(a
, c
->argv
) {
702 if (strpbrk(*a
, WHITESPACE
)) {
713 /* FIXME: this doesn't really handle arguments that have
714 * spaces and ticks in them */
719 void exec_command_dump(ExecCommand
*c
, FILE *f
, const char *prefix
) {
728 cmd
= exec_command_line(c
);
731 "%sCommand Line: %s\n",
732 prefix
, cmd
? cmd
: strerror(ENOMEM
));
737 void exec_command_dump_list(ExecCommand
*c
, FILE *f
, const char *prefix
) {
743 LIST_FOREACH(command
, c
, c
)
744 exec_command_dump(c
, f
, prefix
);
747 static const char* const exec_output_table
[_EXEC_OUTPUT_MAX
] = {
748 [EXEC_OUTPUT_CONSOLE
] = "console",
749 [EXEC_OUTPUT_NULL
] = "null",
750 [EXEC_OUTPUT_SYSLOG
] = "syslog",
751 [EXEC_OUTPUT_KERNEL
] = "kernel"
754 DEFINE_STRING_TABLE_LOOKUP(exec_output
, ExecOutput
);
756 static const char* const exec_input_table
[_EXEC_INPUT_MAX
] = {
757 [EXEC_INPUT_NULL
] = "null",
758 [EXEC_INPUT_CONSOLE
] = "console"
761 DEFINE_STRING_TABLE_LOOKUP(exec_input
, ExecInput
);