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basic: move acquire_data_fd() and fd_duplicate_data_fd() to new data-fd-util.c
[thirdparty/systemd.git] / src / core / execute.c
1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2
3 #include <errno.h>
4 #include <fcntl.h>
5 #include <poll.h>
6 #include <sys/eventfd.h>
7 #include <sys/ioctl.h>
8 #include <sys/mman.h>
9 #include <sys/mount.h>
10 #include <sys/personality.h>
11 #include <sys/prctl.h>
12 #include <sys/shm.h>
13 #include <sys/types.h>
14 #include <sys/un.h>
15 #include <unistd.h>
16 #include <utmpx.h>
17
18 #if HAVE_PAM
19 #include <security/pam_appl.h>
20 #endif
21
22 #if HAVE_SELINUX
23 #include <selinux/selinux.h>
24 #endif
25
26 #if HAVE_SECCOMP
27 #include <seccomp.h>
28 #endif
29
30 #if HAVE_APPARMOR
31 #include <sys/apparmor.h>
32 #endif
33
34 #include "sd-messages.h"
35
36 #include "acl-util.h"
37 #include "af-list.h"
38 #include "alloc-util.h"
39 #if HAVE_APPARMOR
40 #include "apparmor-util.h"
41 #endif
42 #include "async.h"
43 #include "barrier.h"
44 #include "cap-list.h"
45 #include "capability-util.h"
46 #include "cgroup-setup.h"
47 #include "chown-recursive.h"
48 #include "cpu-set-util.h"
49 #include "data-fd-util.h"
50 #include "def.h"
51 #include "env-file.h"
52 #include "env-util.h"
53 #include "errno-list.h"
54 #include "execute.h"
55 #include "exit-status.h"
56 #include "fd-util.h"
57 #include "fileio.h"
58 #include "format-util.h"
59 #include "fs-util.h"
60 #include "glob-util.h"
61 #include "hexdecoct.h"
62 #include "io-util.h"
63 #include "ioprio.h"
64 #include "label.h"
65 #include "log.h"
66 #include "macro.h"
67 #include "manager.h"
68 #include "manager-dump.h"
69 #include "memory-util.h"
70 #include "missing_fs.h"
71 #include "mkdir.h"
72 #include "mount-util.h"
73 #include "mountpoint-util.h"
74 #include "namespace.h"
75 #include "parse-util.h"
76 #include "path-util.h"
77 #include "process-util.h"
78 #include "random-util.h"
79 #include "rlimit-util.h"
80 #include "rm-rf.h"
81 #if HAVE_SECCOMP
82 #include "seccomp-util.h"
83 #endif
84 #include "securebits-util.h"
85 #include "selinux-util.h"
86 #include "signal-util.h"
87 #include "smack-util.h"
88 #include "socket-util.h"
89 #include "special.h"
90 #include "stat-util.h"
91 #include "string-table.h"
92 #include "string-util.h"
93 #include "strv.h"
94 #include "syslog-util.h"
95 #include "terminal-util.h"
96 #include "tmpfile-util.h"
97 #include "umask-util.h"
98 #include "unit-serialize.h"
99 #include "user-util.h"
100 #include "utmp-wtmp.h"
101
102 #define IDLE_TIMEOUT_USEC (5*USEC_PER_SEC)
103 #define IDLE_TIMEOUT2_USEC (1*USEC_PER_SEC)
104
105 #define SNDBUF_SIZE (8*1024*1024)
106
107 static int shift_fds(int fds[], size_t n_fds) {
108 if (n_fds <= 0)
109 return 0;
110
111 /* Modifies the fds array! (sorts it) */
112
113 assert(fds);
114
115 for (int start = 0;;) {
116 int restart_from = -1;
117
118 for (int i = start; i < (int) n_fds; i++) {
119 int nfd;
120
121 /* Already at right index? */
122 if (fds[i] == i+3)
123 continue;
124
125 nfd = fcntl(fds[i], F_DUPFD, i + 3);
126 if (nfd < 0)
127 return -errno;
128
129 safe_close(fds[i]);
130 fds[i] = nfd;
131
132 /* Hmm, the fd we wanted isn't free? Then
133 * let's remember that and try again from here */
134 if (nfd != i+3 && restart_from < 0)
135 restart_from = i;
136 }
137
138 if (restart_from < 0)
139 break;
140
141 start = restart_from;
142 }
143
144 return 0;
145 }
146
147 static int flags_fds(const int fds[], size_t n_socket_fds, size_t n_storage_fds, bool nonblock) {
148 size_t n_fds;
149 int r;
150
151 n_fds = n_socket_fds + n_storage_fds;
152 if (n_fds <= 0)
153 return 0;
154
155 assert(fds);
156
157 /* Drops/Sets O_NONBLOCK and FD_CLOEXEC from the file flags.
158 * O_NONBLOCK only applies to socket activation though. */
159
160 for (size_t i = 0; i < n_fds; i++) {
161
162 if (i < n_socket_fds) {
163 r = fd_nonblock(fds[i], nonblock);
164 if (r < 0)
165 return r;
166 }
167
168 /* We unconditionally drop FD_CLOEXEC from the fds,
169 * since after all we want to pass these fds to our
170 * children */
171
172 r = fd_cloexec(fds[i], false);
173 if (r < 0)
174 return r;
175 }
176
177 return 0;
178 }
179
180 static const char *exec_context_tty_path(const ExecContext *context) {
181 assert(context);
182
183 if (context->stdio_as_fds)
184 return NULL;
185
186 if (context->tty_path)
187 return context->tty_path;
188
189 return "/dev/console";
190 }
191
192 static void exec_context_tty_reset(const ExecContext *context, const ExecParameters *p) {
193 const char *path;
194
195 assert(context);
196
197 path = exec_context_tty_path(context);
198
199 if (context->tty_vhangup) {
200 if (p && p->stdin_fd >= 0)
201 (void) terminal_vhangup_fd(p->stdin_fd);
202 else if (path)
203 (void) terminal_vhangup(path);
204 }
205
206 if (context->tty_reset) {
207 if (p && p->stdin_fd >= 0)
208 (void) reset_terminal_fd(p->stdin_fd, true);
209 else if (path)
210 (void) reset_terminal(path);
211 }
212
213 if (context->tty_vt_disallocate && path)
214 (void) vt_disallocate(path);
215 }
216
217 static bool is_terminal_input(ExecInput i) {
218 return IN_SET(i,
219 EXEC_INPUT_TTY,
220 EXEC_INPUT_TTY_FORCE,
221 EXEC_INPUT_TTY_FAIL);
222 }
223
224 static bool is_terminal_output(ExecOutput o) {
225 return IN_SET(o,
226 EXEC_OUTPUT_TTY,
227 EXEC_OUTPUT_KMSG_AND_CONSOLE,
228 EXEC_OUTPUT_JOURNAL_AND_CONSOLE);
229 }
230
231 static bool is_kmsg_output(ExecOutput o) {
232 return IN_SET(o,
233 EXEC_OUTPUT_KMSG,
234 EXEC_OUTPUT_KMSG_AND_CONSOLE);
235 }
236
237 static bool exec_context_needs_term(const ExecContext *c) {
238 assert(c);
239
240 /* Return true if the execution context suggests we should set $TERM to something useful. */
241
242 if (is_terminal_input(c->std_input))
243 return true;
244
245 if (is_terminal_output(c->std_output))
246 return true;
247
248 if (is_terminal_output(c->std_error))
249 return true;
250
251 return !!c->tty_path;
252 }
253
254 static int open_null_as(int flags, int nfd) {
255 int fd;
256
257 assert(nfd >= 0);
258
259 fd = open("/dev/null", flags|O_NOCTTY);
260 if (fd < 0)
261 return -errno;
262
263 return move_fd(fd, nfd, false);
264 }
265
266 static int connect_journal_socket(
267 int fd,
268 const char *log_namespace,
269 uid_t uid,
270 gid_t gid) {
271
272 union sockaddr_union sa;
273 socklen_t sa_len;
274 uid_t olduid = UID_INVALID;
275 gid_t oldgid = GID_INVALID;
276 const char *j;
277 int r;
278
279 j = log_namespace ?
280 strjoina("/run/systemd/journal.", log_namespace, "/stdout") :
281 "/run/systemd/journal/stdout";
282 r = sockaddr_un_set_path(&sa.un, j);
283 if (r < 0)
284 return r;
285 sa_len = r;
286
287 if (gid_is_valid(gid)) {
288 oldgid = getgid();
289
290 if (setegid(gid) < 0)
291 return -errno;
292 }
293
294 if (uid_is_valid(uid)) {
295 olduid = getuid();
296
297 if (seteuid(uid) < 0) {
298 r = -errno;
299 goto restore_gid;
300 }
301 }
302
303 r = connect(fd, &sa.sa, sa_len) < 0 ? -errno : 0;
304
305 /* If we fail to restore the uid or gid, things will likely
306 fail later on. This should only happen if an LSM interferes. */
307
308 if (uid_is_valid(uid))
309 (void) seteuid(olduid);
310
311 restore_gid:
312 if (gid_is_valid(gid))
313 (void) setegid(oldgid);
314
315 return r;
316 }
317
318 static int connect_logger_as(
319 const Unit *unit,
320 const ExecContext *context,
321 const ExecParameters *params,
322 ExecOutput output,
323 const char *ident,
324 int nfd,
325 uid_t uid,
326 gid_t gid) {
327
328 _cleanup_close_ int fd = -1;
329 int r;
330
331 assert(context);
332 assert(params);
333 assert(output < _EXEC_OUTPUT_MAX);
334 assert(ident);
335 assert(nfd >= 0);
336
337 fd = socket(AF_UNIX, SOCK_STREAM, 0);
338 if (fd < 0)
339 return -errno;
340
341 r = connect_journal_socket(fd, context->log_namespace, uid, gid);
342 if (r < 0)
343 return r;
344
345 if (shutdown(fd, SHUT_RD) < 0)
346 return -errno;
347
348 (void) fd_inc_sndbuf(fd, SNDBUF_SIZE);
349
350 if (dprintf(fd,
351 "%s\n"
352 "%s\n"
353 "%i\n"
354 "%i\n"
355 "%i\n"
356 "%i\n"
357 "%i\n",
358 context->syslog_identifier ?: ident,
359 params->flags & EXEC_PASS_LOG_UNIT ? unit->id : "",
360 context->syslog_priority,
361 !!context->syslog_level_prefix,
362 false,
363 is_kmsg_output(output),
364 is_terminal_output(output)) < 0)
365 return -errno;
366
367 return move_fd(TAKE_FD(fd), nfd, false);
368 }
369
370 static int open_terminal_as(const char *path, int flags, int nfd) {
371 int fd;
372
373 assert(path);
374 assert(nfd >= 0);
375
376 fd = open_terminal(path, flags | O_NOCTTY);
377 if (fd < 0)
378 return fd;
379
380 return move_fd(fd, nfd, false);
381 }
382
383 static int acquire_path(const char *path, int flags, mode_t mode) {
384 union sockaddr_union sa;
385 socklen_t sa_len;
386 _cleanup_close_ int fd = -1;
387 int r;
388
389 assert(path);
390
391 if (IN_SET(flags & O_ACCMODE, O_WRONLY, O_RDWR))
392 flags |= O_CREAT;
393
394 fd = open(path, flags|O_NOCTTY, mode);
395 if (fd >= 0)
396 return TAKE_FD(fd);
397
398 if (errno != ENXIO) /* ENXIO is returned when we try to open() an AF_UNIX file system socket on Linux */
399 return -errno;
400
401 /* So, it appears the specified path could be an AF_UNIX socket. Let's see if we can connect to it. */
402
403 r = sockaddr_un_set_path(&sa.un, path);
404 if (r < 0)
405 return r == -EINVAL ? -ENXIO : r;
406 sa_len = r;
407
408 fd = socket(AF_UNIX, SOCK_STREAM, 0);
409 if (fd < 0)
410 return -errno;
411
412 if (connect(fd, &sa.sa, sa_len) < 0)
413 return errno == EINVAL ? -ENXIO : -errno; /* Propagate initial error if we get EINVAL, i.e. we have
414 * indication that this wasn't an AF_UNIX socket after all */
415
416 if ((flags & O_ACCMODE) == O_RDONLY)
417 r = shutdown(fd, SHUT_WR);
418 else if ((flags & O_ACCMODE) == O_WRONLY)
419 r = shutdown(fd, SHUT_RD);
420 else
421 r = 0;
422 if (r < 0)
423 return -errno;
424
425 return TAKE_FD(fd);
426 }
427
428 static int fixup_input(
429 const ExecContext *context,
430 int socket_fd,
431 bool apply_tty_stdin) {
432
433 ExecInput std_input;
434
435 assert(context);
436
437 std_input = context->std_input;
438
439 if (is_terminal_input(std_input) && !apply_tty_stdin)
440 return EXEC_INPUT_NULL;
441
442 if (std_input == EXEC_INPUT_SOCKET && socket_fd < 0)
443 return EXEC_INPUT_NULL;
444
445 if (std_input == EXEC_INPUT_DATA && context->stdin_data_size == 0)
446 return EXEC_INPUT_NULL;
447
448 return std_input;
449 }
450
451 static int fixup_output(ExecOutput output, int socket_fd) {
452
453 if (output == EXEC_OUTPUT_SOCKET && socket_fd < 0)
454 return EXEC_OUTPUT_INHERIT;
455
456 return output;
457 }
458
459 static int setup_input(
460 const ExecContext *context,
461 const ExecParameters *params,
462 int socket_fd,
463 const int named_iofds[static 3]) {
464
465 ExecInput i;
466
467 assert(context);
468 assert(params);
469 assert(named_iofds);
470
471 if (params->stdin_fd >= 0) {
472 if (dup2(params->stdin_fd, STDIN_FILENO) < 0)
473 return -errno;
474
475 /* Try to make this the controlling tty, if it is a tty, and reset it */
476 if (isatty(STDIN_FILENO)) {
477 (void) ioctl(STDIN_FILENO, TIOCSCTTY, context->std_input == EXEC_INPUT_TTY_FORCE);
478 (void) reset_terminal_fd(STDIN_FILENO, true);
479 }
480
481 return STDIN_FILENO;
482 }
483
484 i = fixup_input(context, socket_fd, params->flags & EXEC_APPLY_TTY_STDIN);
485
486 switch (i) {
487
488 case EXEC_INPUT_NULL:
489 return open_null_as(O_RDONLY, STDIN_FILENO);
490
491 case EXEC_INPUT_TTY:
492 case EXEC_INPUT_TTY_FORCE:
493 case EXEC_INPUT_TTY_FAIL: {
494 int fd;
495
496 fd = acquire_terminal(exec_context_tty_path(context),
497 i == EXEC_INPUT_TTY_FAIL ? ACQUIRE_TERMINAL_TRY :
498 i == EXEC_INPUT_TTY_FORCE ? ACQUIRE_TERMINAL_FORCE :
499 ACQUIRE_TERMINAL_WAIT,
500 USEC_INFINITY);
501 if (fd < 0)
502 return fd;
503
504 return move_fd(fd, STDIN_FILENO, false);
505 }
506
507 case EXEC_INPUT_SOCKET:
508 assert(socket_fd >= 0);
509
510 return dup2(socket_fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
511
512 case EXEC_INPUT_NAMED_FD:
513 assert(named_iofds[STDIN_FILENO] >= 0);
514
515 (void) fd_nonblock(named_iofds[STDIN_FILENO], false);
516 return dup2(named_iofds[STDIN_FILENO], STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
517
518 case EXEC_INPUT_DATA: {
519 int fd;
520
521 fd = acquire_data_fd(context->stdin_data, context->stdin_data_size, 0);
522 if (fd < 0)
523 return fd;
524
525 return move_fd(fd, STDIN_FILENO, false);
526 }
527
528 case EXEC_INPUT_FILE: {
529 bool rw;
530 int fd;
531
532 assert(context->stdio_file[STDIN_FILENO]);
533
534 rw = (context->std_output == EXEC_OUTPUT_FILE && streq_ptr(context->stdio_file[STDIN_FILENO], context->stdio_file[STDOUT_FILENO])) ||
535 (context->std_error == EXEC_OUTPUT_FILE && streq_ptr(context->stdio_file[STDIN_FILENO], context->stdio_file[STDERR_FILENO]));
536
537 fd = acquire_path(context->stdio_file[STDIN_FILENO], rw ? O_RDWR : O_RDONLY, 0666 & ~context->umask);
538 if (fd < 0)
539 return fd;
540
541 return move_fd(fd, STDIN_FILENO, false);
542 }
543
544 default:
545 assert_not_reached("Unknown input type");
546 }
547 }
548
549 static bool can_inherit_stderr_from_stdout(
550 const ExecContext *context,
551 ExecOutput o,
552 ExecOutput e) {
553
554 assert(context);
555
556 /* Returns true, if given the specified STDERR and STDOUT output we can directly dup() the stdout fd to the
557 * stderr fd */
558
559 if (e == EXEC_OUTPUT_INHERIT)
560 return true;
561 if (e != o)
562 return false;
563
564 if (e == EXEC_OUTPUT_NAMED_FD)
565 return streq_ptr(context->stdio_fdname[STDOUT_FILENO], context->stdio_fdname[STDERR_FILENO]);
566
567 if (IN_SET(e, EXEC_OUTPUT_FILE, EXEC_OUTPUT_FILE_APPEND, EXEC_OUTPUT_FILE_TRUNCATE))
568 return streq_ptr(context->stdio_file[STDOUT_FILENO], context->stdio_file[STDERR_FILENO]);
569
570 return true;
571 }
572
573 static int setup_output(
574 const Unit *unit,
575 const ExecContext *context,
576 const ExecParameters *params,
577 int fileno,
578 int socket_fd,
579 const int named_iofds[static 3],
580 const char *ident,
581 uid_t uid,
582 gid_t gid,
583 dev_t *journal_stream_dev,
584 ino_t *journal_stream_ino) {
585
586 ExecOutput o;
587 ExecInput i;
588 int r;
589
590 assert(unit);
591 assert(context);
592 assert(params);
593 assert(ident);
594 assert(journal_stream_dev);
595 assert(journal_stream_ino);
596
597 if (fileno == STDOUT_FILENO && params->stdout_fd >= 0) {
598
599 if (dup2(params->stdout_fd, STDOUT_FILENO) < 0)
600 return -errno;
601
602 return STDOUT_FILENO;
603 }
604
605 if (fileno == STDERR_FILENO && params->stderr_fd >= 0) {
606 if (dup2(params->stderr_fd, STDERR_FILENO) < 0)
607 return -errno;
608
609 return STDERR_FILENO;
610 }
611
612 i = fixup_input(context, socket_fd, params->flags & EXEC_APPLY_TTY_STDIN);
613 o = fixup_output(context->std_output, socket_fd);
614
615 if (fileno == STDERR_FILENO) {
616 ExecOutput e;
617 e = fixup_output(context->std_error, socket_fd);
618
619 /* This expects the input and output are already set up */
620
621 /* Don't change the stderr file descriptor if we inherit all
622 * the way and are not on a tty */
623 if (e == EXEC_OUTPUT_INHERIT &&
624 o == EXEC_OUTPUT_INHERIT &&
625 i == EXEC_INPUT_NULL &&
626 !is_terminal_input(context->std_input) &&
627 getppid() != 1)
628 return fileno;
629
630 /* Duplicate from stdout if possible */
631 if (can_inherit_stderr_from_stdout(context, o, e))
632 return dup2(STDOUT_FILENO, fileno) < 0 ? -errno : fileno;
633
634 o = e;
635
636 } else if (o == EXEC_OUTPUT_INHERIT) {
637 /* If input got downgraded, inherit the original value */
638 if (i == EXEC_INPUT_NULL && is_terminal_input(context->std_input))
639 return open_terminal_as(exec_context_tty_path(context), O_WRONLY, fileno);
640
641 /* If the input is connected to anything that's not a /dev/null or a data fd, inherit that... */
642 if (!IN_SET(i, EXEC_INPUT_NULL, EXEC_INPUT_DATA))
643 return dup2(STDIN_FILENO, fileno) < 0 ? -errno : fileno;
644
645 /* If we are not started from PID 1 we just inherit STDOUT from our parent process. */
646 if (getppid() != 1)
647 return fileno;
648
649 /* We need to open /dev/null here anew, to get the right access mode. */
650 return open_null_as(O_WRONLY, fileno);
651 }
652
653 switch (o) {
654
655 case EXEC_OUTPUT_NULL:
656 return open_null_as(O_WRONLY, fileno);
657
658 case EXEC_OUTPUT_TTY:
659 if (is_terminal_input(i))
660 return dup2(STDIN_FILENO, fileno) < 0 ? -errno : fileno;
661
662 /* We don't reset the terminal if this is just about output */
663 return open_terminal_as(exec_context_tty_path(context), O_WRONLY, fileno);
664
665 case EXEC_OUTPUT_KMSG:
666 case EXEC_OUTPUT_KMSG_AND_CONSOLE:
667 case EXEC_OUTPUT_JOURNAL:
668 case EXEC_OUTPUT_JOURNAL_AND_CONSOLE:
669 r = connect_logger_as(unit, context, params, o, ident, fileno, uid, gid);
670 if (r < 0) {
671 log_unit_warning_errno(unit, r, "Failed to connect %s to the journal socket, ignoring: %m",
672 fileno == STDOUT_FILENO ? "stdout" : "stderr");
673 r = open_null_as(O_WRONLY, fileno);
674 } else {
675 struct stat st;
676
677 /* If we connected this fd to the journal via a stream, patch the device/inode into the passed
678 * parameters, but only then. This is useful so that we can set $JOURNAL_STREAM that permits
679 * services to detect whether they are connected to the journal or not.
680 *
681 * If both stdout and stderr are connected to a stream then let's make sure to store the data
682 * about STDERR as that's usually the best way to do logging. */
683
684 if (fstat(fileno, &st) >= 0 &&
685 (*journal_stream_ino == 0 || fileno == STDERR_FILENO)) {
686 *journal_stream_dev = st.st_dev;
687 *journal_stream_ino = st.st_ino;
688 }
689 }
690 return r;
691
692 case EXEC_OUTPUT_SOCKET:
693 assert(socket_fd >= 0);
694
695 return dup2(socket_fd, fileno) < 0 ? -errno : fileno;
696
697 case EXEC_OUTPUT_NAMED_FD:
698 assert(named_iofds[fileno] >= 0);
699
700 (void) fd_nonblock(named_iofds[fileno], false);
701 return dup2(named_iofds[fileno], fileno) < 0 ? -errno : fileno;
702
703 case EXEC_OUTPUT_FILE:
704 case EXEC_OUTPUT_FILE_APPEND:
705 case EXEC_OUTPUT_FILE_TRUNCATE: {
706 bool rw;
707 int fd, flags;
708
709 assert(context->stdio_file[fileno]);
710
711 rw = context->std_input == EXEC_INPUT_FILE &&
712 streq_ptr(context->stdio_file[fileno], context->stdio_file[STDIN_FILENO]);
713
714 if (rw)
715 return dup2(STDIN_FILENO, fileno) < 0 ? -errno : fileno;
716
717 flags = O_WRONLY;
718 if (o == EXEC_OUTPUT_FILE_APPEND)
719 flags |= O_APPEND;
720 else if (o == EXEC_OUTPUT_FILE_TRUNCATE)
721 flags |= O_TRUNC;
722
723 fd = acquire_path(context->stdio_file[fileno], flags, 0666 & ~context->umask);
724 if (fd < 0)
725 return fd;
726
727 return move_fd(fd, fileno, 0);
728 }
729
730 default:
731 assert_not_reached("Unknown error type");
732 }
733 }
734
735 static int chown_terminal(int fd, uid_t uid) {
736 int r;
737
738 assert(fd >= 0);
739
740 /* Before we chown/chmod the TTY, let's ensure this is actually a tty */
741 if (isatty(fd) < 1) {
742 if (IN_SET(errno, EINVAL, ENOTTY))
743 return 0; /* not a tty */
744
745 return -errno;
746 }
747
748 /* This might fail. What matters are the results. */
749 r = fchmod_and_chown(fd, TTY_MODE, uid, GID_INVALID);
750 if (r < 0)
751 return r;
752
753 return 1;
754 }
755
756 static int setup_confirm_stdio(const char *vc, int *_saved_stdin, int *_saved_stdout) {
757 _cleanup_close_ int fd = -1, saved_stdin = -1, saved_stdout = -1;
758 int r;
759
760 assert(_saved_stdin);
761 assert(_saved_stdout);
762
763 saved_stdin = fcntl(STDIN_FILENO, F_DUPFD, 3);
764 if (saved_stdin < 0)
765 return -errno;
766
767 saved_stdout = fcntl(STDOUT_FILENO, F_DUPFD, 3);
768 if (saved_stdout < 0)
769 return -errno;
770
771 fd = acquire_terminal(vc, ACQUIRE_TERMINAL_WAIT, DEFAULT_CONFIRM_USEC);
772 if (fd < 0)
773 return fd;
774
775 r = chown_terminal(fd, getuid());
776 if (r < 0)
777 return r;
778
779 r = reset_terminal_fd(fd, true);
780 if (r < 0)
781 return r;
782
783 r = rearrange_stdio(fd, fd, STDERR_FILENO);
784 fd = -1;
785 if (r < 0)
786 return r;
787
788 *_saved_stdin = saved_stdin;
789 *_saved_stdout = saved_stdout;
790
791 saved_stdin = saved_stdout = -1;
792
793 return 0;
794 }
795
796 static void write_confirm_error_fd(int err, int fd, const Unit *u) {
797 assert(err < 0);
798
799 if (err == -ETIMEDOUT)
800 dprintf(fd, "Confirmation question timed out for %s, assuming positive response.\n", u->id);
801 else {
802 errno = -err;
803 dprintf(fd, "Couldn't ask confirmation for %s: %m, assuming positive response.\n", u->id);
804 }
805 }
806
807 static void write_confirm_error(int err, const char *vc, const Unit *u) {
808 _cleanup_close_ int fd = -1;
809
810 assert(vc);
811
812 fd = open_terminal(vc, O_WRONLY|O_NOCTTY|O_CLOEXEC);
813 if (fd < 0)
814 return;
815
816 write_confirm_error_fd(err, fd, u);
817 }
818
819 static int restore_confirm_stdio(int *saved_stdin, int *saved_stdout) {
820 int r = 0;
821
822 assert(saved_stdin);
823 assert(saved_stdout);
824
825 release_terminal();
826
827 if (*saved_stdin >= 0)
828 if (dup2(*saved_stdin, STDIN_FILENO) < 0)
829 r = -errno;
830
831 if (*saved_stdout >= 0)
832 if (dup2(*saved_stdout, STDOUT_FILENO) < 0)
833 r = -errno;
834
835 *saved_stdin = safe_close(*saved_stdin);
836 *saved_stdout = safe_close(*saved_stdout);
837
838 return r;
839 }
840
841 enum {
842 CONFIRM_PRETEND_FAILURE = -1,
843 CONFIRM_PRETEND_SUCCESS = 0,
844 CONFIRM_EXECUTE = 1,
845 };
846
847 static int ask_for_confirmation(const char *vc, Unit *u, const char *cmdline) {
848 int saved_stdout = -1, saved_stdin = -1, r;
849 _cleanup_free_ char *e = NULL;
850 char c;
851
852 /* For any internal errors, assume a positive response. */
853 r = setup_confirm_stdio(vc, &saved_stdin, &saved_stdout);
854 if (r < 0) {
855 write_confirm_error(r, vc, u);
856 return CONFIRM_EXECUTE;
857 }
858
859 /* confirm_spawn might have been disabled while we were sleeping. */
860 if (manager_is_confirm_spawn_disabled(u->manager)) {
861 r = 1;
862 goto restore_stdio;
863 }
864
865 e = ellipsize(cmdline, 60, 100);
866 if (!e) {
867 log_oom();
868 r = CONFIRM_EXECUTE;
869 goto restore_stdio;
870 }
871
872 for (;;) {
873 r = ask_char(&c, "yfshiDjcn", "Execute %s? [y, f, s – h for help] ", e);
874 if (r < 0) {
875 write_confirm_error_fd(r, STDOUT_FILENO, u);
876 r = CONFIRM_EXECUTE;
877 goto restore_stdio;
878 }
879
880 switch (c) {
881 case 'c':
882 printf("Resuming normal execution.\n");
883 manager_disable_confirm_spawn();
884 r = 1;
885 break;
886 case 'D':
887 unit_dump(u, stdout, " ");
888 continue; /* ask again */
889 case 'f':
890 printf("Failing execution.\n");
891 r = CONFIRM_PRETEND_FAILURE;
892 break;
893 case 'h':
894 printf(" c - continue, proceed without asking anymore\n"
895 " D - dump, show the state of the unit\n"
896 " f - fail, don't execute the command and pretend it failed\n"
897 " h - help\n"
898 " i - info, show a short summary of the unit\n"
899 " j - jobs, show jobs that are in progress\n"
900 " s - skip, don't execute the command and pretend it succeeded\n"
901 " y - yes, execute the command\n");
902 continue; /* ask again */
903 case 'i':
904 printf(" Description: %s\n"
905 " Unit: %s\n"
906 " Command: %s\n",
907 u->id, u->description, cmdline);
908 continue; /* ask again */
909 case 'j':
910 manager_dump_jobs(u->manager, stdout, " ");
911 continue; /* ask again */
912 case 'n':
913 /* 'n' was removed in favor of 'f'. */
914 printf("Didn't understand 'n', did you mean 'f'?\n");
915 continue; /* ask again */
916 case 's':
917 printf("Skipping execution.\n");
918 r = CONFIRM_PRETEND_SUCCESS;
919 break;
920 case 'y':
921 r = CONFIRM_EXECUTE;
922 break;
923 default:
924 assert_not_reached("Unhandled choice");
925 }
926 break;
927 }
928
929 restore_stdio:
930 restore_confirm_stdio(&saved_stdin, &saved_stdout);
931 return r;
932 }
933
934 static int get_fixed_user(const ExecContext *c, const char **user,
935 uid_t *uid, gid_t *gid,
936 const char **home, const char **shell) {
937 int r;
938 const char *name;
939
940 assert(c);
941
942 if (!c->user)
943 return 0;
944
945 /* Note that we don't set $HOME or $SHELL if they are not particularly enlightening anyway
946 * (i.e. are "/" or "/bin/nologin"). */
947
948 name = c->user;
949 r = get_user_creds(&name, uid, gid, home, shell, USER_CREDS_CLEAN);
950 if (r < 0)
951 return r;
952
953 *user = name;
954 return 0;
955 }
956
957 static int get_fixed_group(const ExecContext *c, const char **group, gid_t *gid) {
958 int r;
959 const char *name;
960
961 assert(c);
962
963 if (!c->group)
964 return 0;
965
966 name = c->group;
967 r = get_group_creds(&name, gid, 0);
968 if (r < 0)
969 return r;
970
971 *group = name;
972 return 0;
973 }
974
975 static int get_supplementary_groups(const ExecContext *c, const char *user,
976 const char *group, gid_t gid,
977 gid_t **supplementary_gids, int *ngids) {
978 char **i;
979 int r, k = 0;
980 int ngroups_max;
981 bool keep_groups = false;
982 gid_t *groups = NULL;
983 _cleanup_free_ gid_t *l_gids = NULL;
984
985 assert(c);
986
987 /*
988 * If user is given, then lookup GID and supplementary groups list.
989 * We avoid NSS lookups for gid=0. Also we have to initialize groups
990 * here and as early as possible so we keep the list of supplementary
991 * groups of the caller.
992 */
993 if (user && gid_is_valid(gid) && gid != 0) {
994 /* First step, initialize groups from /etc/groups */
995 if (initgroups(user, gid) < 0)
996 return -errno;
997
998 keep_groups = true;
999 }
1000
1001 if (strv_isempty(c->supplementary_groups))
1002 return 0;
1003
1004 /*
1005 * If SupplementaryGroups= was passed then NGROUPS_MAX has to
1006 * be positive, otherwise fail.
1007 */
1008 errno = 0;
1009 ngroups_max = (int) sysconf(_SC_NGROUPS_MAX);
1010 if (ngroups_max <= 0)
1011 return errno_or_else(EOPNOTSUPP);
1012
1013 l_gids = new(gid_t, ngroups_max);
1014 if (!l_gids)
1015 return -ENOMEM;
1016
1017 if (keep_groups) {
1018 /*
1019 * Lookup the list of groups that the user belongs to, we
1020 * avoid NSS lookups here too for gid=0.
1021 */
1022 k = ngroups_max;
1023 if (getgrouplist(user, gid, l_gids, &k) < 0)
1024 return -EINVAL;
1025 } else
1026 k = 0;
1027
1028 STRV_FOREACH(i, c->supplementary_groups) {
1029 const char *g;
1030
1031 if (k >= ngroups_max)
1032 return -E2BIG;
1033
1034 g = *i;
1035 r = get_group_creds(&g, l_gids+k, 0);
1036 if (r < 0)
1037 return r;
1038
1039 k++;
1040 }
1041
1042 /*
1043 * Sets ngids to zero to drop all supplementary groups, happens
1044 * when we are under root and SupplementaryGroups= is empty.
1045 */
1046 if (k == 0) {
1047 *ngids = 0;
1048 return 0;
1049 }
1050
1051 /* Otherwise get the final list of supplementary groups */
1052 groups = memdup(l_gids, sizeof(gid_t) * k);
1053 if (!groups)
1054 return -ENOMEM;
1055
1056 *supplementary_gids = groups;
1057 *ngids = k;
1058
1059 groups = NULL;
1060
1061 return 0;
1062 }
1063
1064 static int enforce_groups(gid_t gid, const gid_t *supplementary_gids, int ngids) {
1065 int r;
1066
1067 /* Handle SupplementaryGroups= if it is not empty */
1068 if (ngids > 0) {
1069 r = maybe_setgroups(ngids, supplementary_gids);
1070 if (r < 0)
1071 return r;
1072 }
1073
1074 if (gid_is_valid(gid)) {
1075 /* Then set our gids */
1076 if (setresgid(gid, gid, gid) < 0)
1077 return -errno;
1078 }
1079
1080 return 0;
1081 }
1082
1083 static int set_securebits(int bits, int mask) {
1084 int current, applied;
1085 current = prctl(PR_GET_SECUREBITS);
1086 if (current < 0)
1087 return -errno;
1088 /* Clear all securebits defined in mask and set bits */
1089 applied = (current & ~mask) | bits;
1090 if (current == applied)
1091 return 0;
1092 if (prctl(PR_SET_SECUREBITS, applied) < 0)
1093 return -errno;
1094 return 1;
1095 }
1096
1097 static int enforce_user(const ExecContext *context, uid_t uid) {
1098 assert(context);
1099 int r;
1100
1101 if (!uid_is_valid(uid))
1102 return 0;
1103
1104 /* Sets (but doesn't look up) the uid and make sure we keep the
1105 * capabilities while doing so. For setting secure bits the capability CAP_SETPCAP is
1106 * required, so we also need keep-caps in this case.
1107 */
1108
1109 if (context->capability_ambient_set != 0 || context->secure_bits != 0) {
1110
1111 /* First step: If we need to keep capabilities but
1112 * drop privileges we need to make sure we keep our
1113 * caps, while we drop privileges. */
1114 if (uid != 0) {
1115 /* Add KEEP_CAPS to the securebits */
1116 r = set_securebits(1<<SECURE_KEEP_CAPS, 0);
1117 if (r < 0)
1118 return r;
1119 }
1120 }
1121
1122 /* Second step: actually set the uids */
1123 if (setresuid(uid, uid, uid) < 0)
1124 return -errno;
1125
1126 /* At this point we should have all necessary capabilities but
1127 are otherwise a normal user. However, the caps might got
1128 corrupted due to the setresuid() so we need clean them up
1129 later. This is done outside of this call. */
1130
1131 return 0;
1132 }
1133
1134 #if HAVE_PAM
1135
1136 static int null_conv(
1137 int num_msg,
1138 const struct pam_message **msg,
1139 struct pam_response **resp,
1140 void *appdata_ptr) {
1141
1142 /* We don't support conversations */
1143
1144 return PAM_CONV_ERR;
1145 }
1146
1147 #endif
1148
1149 static int setup_pam(
1150 const char *name,
1151 const char *user,
1152 uid_t uid,
1153 gid_t gid,
1154 const char *tty,
1155 char ***env,
1156 const int fds[], size_t n_fds) {
1157
1158 #if HAVE_PAM
1159
1160 static const struct pam_conv conv = {
1161 .conv = null_conv,
1162 .appdata_ptr = NULL
1163 };
1164
1165 _cleanup_(barrier_destroy) Barrier barrier = BARRIER_NULL;
1166 pam_handle_t *handle = NULL;
1167 sigset_t old_ss;
1168 int pam_code = PAM_SUCCESS, r;
1169 char **nv, **e = NULL;
1170 bool close_session = false;
1171 pid_t pam_pid = 0, parent_pid;
1172 int flags = 0;
1173
1174 assert(name);
1175 assert(user);
1176 assert(env);
1177
1178 /* We set up PAM in the parent process, then fork. The child
1179 * will then stay around until killed via PR_GET_PDEATHSIG or
1180 * systemd via the cgroup logic. It will then remove the PAM
1181 * session again. The parent process will exec() the actual
1182 * daemon. We do things this way to ensure that the main PID
1183 * of the daemon is the one we initially fork()ed. */
1184
1185 r = barrier_create(&barrier);
1186 if (r < 0)
1187 goto fail;
1188
1189 if (log_get_max_level() < LOG_DEBUG)
1190 flags |= PAM_SILENT;
1191
1192 pam_code = pam_start(name, user, &conv, &handle);
1193 if (pam_code != PAM_SUCCESS) {
1194 handle = NULL;
1195 goto fail;
1196 }
1197
1198 if (!tty) {
1199 _cleanup_free_ char *q = NULL;
1200
1201 /* Hmm, so no TTY was explicitly passed, but an fd passed to us directly might be a TTY. Let's figure
1202 * out if that's the case, and read the TTY off it. */
1203
1204 if (getttyname_malloc(STDIN_FILENO, &q) >= 0)
1205 tty = strjoina("/dev/", q);
1206 }
1207
1208 if (tty) {
1209 pam_code = pam_set_item(handle, PAM_TTY, tty);
1210 if (pam_code != PAM_SUCCESS)
1211 goto fail;
1212 }
1213
1214 STRV_FOREACH(nv, *env) {
1215 pam_code = pam_putenv(handle, *nv);
1216 if (pam_code != PAM_SUCCESS)
1217 goto fail;
1218 }
1219
1220 pam_code = pam_acct_mgmt(handle, flags);
1221 if (pam_code != PAM_SUCCESS)
1222 goto fail;
1223
1224 pam_code = pam_setcred(handle, PAM_ESTABLISH_CRED | flags);
1225 if (pam_code != PAM_SUCCESS)
1226 log_debug("pam_setcred() failed, ignoring: %s", pam_strerror(handle, pam_code));
1227
1228 pam_code = pam_open_session(handle, flags);
1229 if (pam_code != PAM_SUCCESS)
1230 goto fail;
1231
1232 close_session = true;
1233
1234 e = pam_getenvlist(handle);
1235 if (!e) {
1236 pam_code = PAM_BUF_ERR;
1237 goto fail;
1238 }
1239
1240 /* Block SIGTERM, so that we know that it won't get lost in
1241 * the child */
1242
1243 assert_se(sigprocmask_many(SIG_BLOCK, &old_ss, SIGTERM, -1) >= 0);
1244
1245 parent_pid = getpid_cached();
1246
1247 r = safe_fork("(sd-pam)", 0, &pam_pid);
1248 if (r < 0)
1249 goto fail;
1250 if (r == 0) {
1251 int sig, ret = EXIT_PAM;
1252
1253 /* The child's job is to reset the PAM session on
1254 * termination */
1255 barrier_set_role(&barrier, BARRIER_CHILD);
1256
1257 /* Make sure we don't keep open the passed fds in this child. We assume that otherwise only
1258 * those fds are open here that have been opened by PAM. */
1259 (void) close_many(fds, n_fds);
1260
1261 /* Drop privileges - we don't need any to pam_close_session
1262 * and this will make PR_SET_PDEATHSIG work in most cases.
1263 * If this fails, ignore the error - but expect sd-pam threads
1264 * to fail to exit normally */
1265
1266 r = maybe_setgroups(0, NULL);
1267 if (r < 0)
1268 log_warning_errno(r, "Failed to setgroups() in sd-pam: %m");
1269 if (setresgid(gid, gid, gid) < 0)
1270 log_warning_errno(errno, "Failed to setresgid() in sd-pam: %m");
1271 if (setresuid(uid, uid, uid) < 0)
1272 log_warning_errno(errno, "Failed to setresuid() in sd-pam: %m");
1273
1274 (void) ignore_signals(SIGPIPE);
1275
1276 /* Wait until our parent died. This will only work if
1277 * the above setresuid() succeeds, otherwise the kernel
1278 * will not allow unprivileged parents kill their privileged
1279 * children this way. We rely on the control groups kill logic
1280 * to do the rest for us. */
1281 if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
1282 goto child_finish;
1283
1284 /* Tell the parent that our setup is done. This is especially
1285 * important regarding dropping privileges. Otherwise, unit
1286 * setup might race against our setresuid(2) call.
1287 *
1288 * If the parent aborted, we'll detect this below, hence ignore
1289 * return failure here. */
1290 (void) barrier_place(&barrier);
1291
1292 /* Check if our parent process might already have died? */
1293 if (getppid() == parent_pid) {
1294 sigset_t ss;
1295
1296 assert_se(sigemptyset(&ss) >= 0);
1297 assert_se(sigaddset(&ss, SIGTERM) >= 0);
1298
1299 for (;;) {
1300 if (sigwait(&ss, &sig) < 0) {
1301 if (errno == EINTR)
1302 continue;
1303
1304 goto child_finish;
1305 }
1306
1307 assert(sig == SIGTERM);
1308 break;
1309 }
1310 }
1311
1312 pam_code = pam_setcred(handle, PAM_DELETE_CRED | flags);
1313 if (pam_code != PAM_SUCCESS)
1314 goto child_finish;
1315
1316 /* If our parent died we'll end the session */
1317 if (getppid() != parent_pid) {
1318 pam_code = pam_close_session(handle, flags);
1319 if (pam_code != PAM_SUCCESS)
1320 goto child_finish;
1321 }
1322
1323 ret = 0;
1324
1325 child_finish:
1326 pam_end(handle, pam_code | flags);
1327 _exit(ret);
1328 }
1329
1330 barrier_set_role(&barrier, BARRIER_PARENT);
1331
1332 /* If the child was forked off successfully it will do all the
1333 * cleanups, so forget about the handle here. */
1334 handle = NULL;
1335
1336 /* Unblock SIGTERM again in the parent */
1337 assert_se(sigprocmask(SIG_SETMASK, &old_ss, NULL) >= 0);
1338
1339 /* We close the log explicitly here, since the PAM modules
1340 * might have opened it, but we don't want this fd around. */
1341 closelog();
1342
1343 /* Synchronously wait for the child to initialize. We don't care for
1344 * errors as we cannot recover. However, warn loudly if it happens. */
1345 if (!barrier_place_and_sync(&barrier))
1346 log_error("PAM initialization failed");
1347
1348 return strv_free_and_replace(*env, e);
1349
1350 fail:
1351 if (pam_code != PAM_SUCCESS) {
1352 log_error("PAM failed: %s", pam_strerror(handle, pam_code));
1353 r = -EPERM; /* PAM errors do not map to errno */
1354 } else
1355 log_error_errno(r, "PAM failed: %m");
1356
1357 if (handle) {
1358 if (close_session)
1359 pam_code = pam_close_session(handle, flags);
1360
1361 pam_end(handle, pam_code | flags);
1362 }
1363
1364 strv_free(e);
1365 closelog();
1366
1367 return r;
1368 #else
1369 return 0;
1370 #endif
1371 }
1372
1373 static void rename_process_from_path(const char *path) {
1374 char process_name[11];
1375 const char *p;
1376 size_t l;
1377
1378 /* This resulting string must fit in 10 chars (i.e. the length
1379 * of "/sbin/init") to look pretty in /bin/ps */
1380
1381 p = basename(path);
1382 if (isempty(p)) {
1383 rename_process("(...)");
1384 return;
1385 }
1386
1387 l = strlen(p);
1388 if (l > 8) {
1389 /* The end of the process name is usually more
1390 * interesting, since the first bit might just be
1391 * "systemd-" */
1392 p = p + l - 8;
1393 l = 8;
1394 }
1395
1396 process_name[0] = '(';
1397 memcpy(process_name+1, p, l);
1398 process_name[1+l] = ')';
1399 process_name[1+l+1] = 0;
1400
1401 rename_process(process_name);
1402 }
1403
1404 static bool context_has_address_families(const ExecContext *c) {
1405 assert(c);
1406
1407 return c->address_families_allow_list ||
1408 !set_isempty(c->address_families);
1409 }
1410
1411 static bool context_has_syscall_filters(const ExecContext *c) {
1412 assert(c);
1413
1414 return c->syscall_allow_list ||
1415 !hashmap_isempty(c->syscall_filter);
1416 }
1417
1418 static bool context_has_syscall_logs(const ExecContext *c) {
1419 assert(c);
1420
1421 return c->syscall_log_allow_list ||
1422 !hashmap_isempty(c->syscall_log);
1423 }
1424
1425 static bool context_has_no_new_privileges(const ExecContext *c) {
1426 assert(c);
1427
1428 if (c->no_new_privileges)
1429 return true;
1430
1431 if (have_effective_cap(CAP_SYS_ADMIN)) /* if we are privileged, we don't need NNP */
1432 return false;
1433
1434 /* We need NNP if we have any form of seccomp and are unprivileged */
1435 return c->lock_personality ||
1436 c->memory_deny_write_execute ||
1437 c->private_devices ||
1438 c->protect_clock ||
1439 c->protect_hostname ||
1440 c->protect_kernel_tunables ||
1441 c->protect_kernel_modules ||
1442 c->protect_kernel_logs ||
1443 context_has_address_families(c) ||
1444 exec_context_restrict_namespaces_set(c) ||
1445 c->restrict_realtime ||
1446 c->restrict_suid_sgid ||
1447 !set_isempty(c->syscall_archs) ||
1448 context_has_syscall_filters(c) ||
1449 context_has_syscall_logs(c);
1450 }
1451
1452 static bool exec_context_has_credentials(const ExecContext *context) {
1453
1454 assert(context);
1455
1456 return !hashmap_isempty(context->set_credentials) ||
1457 context->load_credentials;
1458 }
1459
1460 #if HAVE_SECCOMP
1461
1462 static bool skip_seccomp_unavailable(const Unit* u, const char* msg) {
1463
1464 if (is_seccomp_available())
1465 return false;
1466
1467 log_unit_debug(u, "SECCOMP features not detected in the kernel, skipping %s", msg);
1468 return true;
1469 }
1470
1471 static int apply_syscall_filter(const Unit* u, const ExecContext *c, bool needs_ambient_hack) {
1472 uint32_t negative_action, default_action, action;
1473 int r;
1474
1475 assert(u);
1476 assert(c);
1477
1478 if (!context_has_syscall_filters(c))
1479 return 0;
1480
1481 if (skip_seccomp_unavailable(u, "SystemCallFilter="))
1482 return 0;
1483
1484 negative_action = c->syscall_errno == SECCOMP_ERROR_NUMBER_KILL ? scmp_act_kill_process() : SCMP_ACT_ERRNO(c->syscall_errno);
1485
1486 if (c->syscall_allow_list) {
1487 default_action = negative_action;
1488 action = SCMP_ACT_ALLOW;
1489 } else {
1490 default_action = SCMP_ACT_ALLOW;
1491 action = negative_action;
1492 }
1493
1494 if (needs_ambient_hack) {
1495 r = seccomp_filter_set_add(c->syscall_filter, c->syscall_allow_list, syscall_filter_sets + SYSCALL_FILTER_SET_SETUID);
1496 if (r < 0)
1497 return r;
1498 }
1499
1500 return seccomp_load_syscall_filter_set_raw(default_action, c->syscall_filter, action, false);
1501 }
1502
1503 static int apply_syscall_log(const Unit* u, const ExecContext *c) {
1504 #ifdef SCMP_ACT_LOG
1505 uint32_t default_action, action;
1506 #endif
1507
1508 assert(u);
1509 assert(c);
1510
1511 if (!context_has_syscall_logs(c))
1512 return 0;
1513
1514 #ifdef SCMP_ACT_LOG
1515 if (skip_seccomp_unavailable(u, "SystemCallLog="))
1516 return 0;
1517
1518 if (c->syscall_log_allow_list) {
1519 /* Log nothing but the ones listed */
1520 default_action = SCMP_ACT_ALLOW;
1521 action = SCMP_ACT_LOG;
1522 } else {
1523 /* Log everything but the ones listed */
1524 default_action = SCMP_ACT_LOG;
1525 action = SCMP_ACT_ALLOW;
1526 }
1527
1528 return seccomp_load_syscall_filter_set_raw(default_action, c->syscall_log, action, false);
1529 #else
1530 /* old libseccomp */
1531 log_unit_debug(u, "SECCOMP feature SCMP_ACT_LOG not available, skipping SystemCallLog=");
1532 return 0;
1533 #endif
1534 }
1535
1536 static int apply_syscall_archs(const Unit *u, const ExecContext *c) {
1537 assert(u);
1538 assert(c);
1539
1540 if (set_isempty(c->syscall_archs))
1541 return 0;
1542
1543 if (skip_seccomp_unavailable(u, "SystemCallArchitectures="))
1544 return 0;
1545
1546 return seccomp_restrict_archs(c->syscall_archs);
1547 }
1548
1549 static int apply_address_families(const Unit* u, const ExecContext *c) {
1550 assert(u);
1551 assert(c);
1552
1553 if (!context_has_address_families(c))
1554 return 0;
1555
1556 if (skip_seccomp_unavailable(u, "RestrictAddressFamilies="))
1557 return 0;
1558
1559 return seccomp_restrict_address_families(c->address_families, c->address_families_allow_list);
1560 }
1561
1562 static int apply_memory_deny_write_execute(const Unit* u, const ExecContext *c) {
1563 assert(u);
1564 assert(c);
1565
1566 if (!c->memory_deny_write_execute)
1567 return 0;
1568
1569 if (skip_seccomp_unavailable(u, "MemoryDenyWriteExecute="))
1570 return 0;
1571
1572 return seccomp_memory_deny_write_execute();
1573 }
1574
1575 static int apply_restrict_realtime(const Unit* u, const ExecContext *c) {
1576 assert(u);
1577 assert(c);
1578
1579 if (!c->restrict_realtime)
1580 return 0;
1581
1582 if (skip_seccomp_unavailable(u, "RestrictRealtime="))
1583 return 0;
1584
1585 return seccomp_restrict_realtime();
1586 }
1587
1588 static int apply_restrict_suid_sgid(const Unit* u, const ExecContext *c) {
1589 assert(u);
1590 assert(c);
1591
1592 if (!c->restrict_suid_sgid)
1593 return 0;
1594
1595 if (skip_seccomp_unavailable(u, "RestrictSUIDSGID="))
1596 return 0;
1597
1598 return seccomp_restrict_suid_sgid();
1599 }
1600
1601 static int apply_protect_sysctl(const Unit *u, const ExecContext *c) {
1602 assert(u);
1603 assert(c);
1604
1605 /* Turn off the legacy sysctl() system call. Many distributions turn this off while building the kernel, but
1606 * let's protect even those systems where this is left on in the kernel. */
1607
1608 if (!c->protect_kernel_tunables)
1609 return 0;
1610
1611 if (skip_seccomp_unavailable(u, "ProtectKernelTunables="))
1612 return 0;
1613
1614 return seccomp_protect_sysctl();
1615 }
1616
1617 static int apply_protect_kernel_modules(const Unit *u, const ExecContext *c) {
1618 assert(u);
1619 assert(c);
1620
1621 /* Turn off module syscalls on ProtectKernelModules=yes */
1622
1623 if (!c->protect_kernel_modules)
1624 return 0;
1625
1626 if (skip_seccomp_unavailable(u, "ProtectKernelModules="))
1627 return 0;
1628
1629 return seccomp_load_syscall_filter_set(SCMP_ACT_ALLOW, syscall_filter_sets + SYSCALL_FILTER_SET_MODULE, SCMP_ACT_ERRNO(EPERM), false);
1630 }
1631
1632 static int apply_protect_kernel_logs(const Unit *u, const ExecContext *c) {
1633 assert(u);
1634 assert(c);
1635
1636 if (!c->protect_kernel_logs)
1637 return 0;
1638
1639 if (skip_seccomp_unavailable(u, "ProtectKernelLogs="))
1640 return 0;
1641
1642 return seccomp_protect_syslog();
1643 }
1644
1645 static int apply_protect_clock(const Unit *u, const ExecContext *c) {
1646 assert(u);
1647 assert(c);
1648
1649 if (!c->protect_clock)
1650 return 0;
1651
1652 if (skip_seccomp_unavailable(u, "ProtectClock="))
1653 return 0;
1654
1655 return seccomp_load_syscall_filter_set(SCMP_ACT_ALLOW, syscall_filter_sets + SYSCALL_FILTER_SET_CLOCK, SCMP_ACT_ERRNO(EPERM), false);
1656 }
1657
1658 static int apply_private_devices(const Unit *u, const ExecContext *c) {
1659 assert(u);
1660 assert(c);
1661
1662 /* If PrivateDevices= is set, also turn off iopl and all @raw-io syscalls. */
1663
1664 if (!c->private_devices)
1665 return 0;
1666
1667 if (skip_seccomp_unavailable(u, "PrivateDevices="))
1668 return 0;
1669
1670 return seccomp_load_syscall_filter_set(SCMP_ACT_ALLOW, syscall_filter_sets + SYSCALL_FILTER_SET_RAW_IO, SCMP_ACT_ERRNO(EPERM), false);
1671 }
1672
1673 static int apply_restrict_namespaces(const Unit *u, const ExecContext *c) {
1674 assert(u);
1675 assert(c);
1676
1677 if (!exec_context_restrict_namespaces_set(c))
1678 return 0;
1679
1680 if (skip_seccomp_unavailable(u, "RestrictNamespaces="))
1681 return 0;
1682
1683 return seccomp_restrict_namespaces(c->restrict_namespaces);
1684 }
1685
1686 static int apply_lock_personality(const Unit* u, const ExecContext *c) {
1687 unsigned long personality;
1688 int r;
1689
1690 assert(u);
1691 assert(c);
1692
1693 if (!c->lock_personality)
1694 return 0;
1695
1696 if (skip_seccomp_unavailable(u, "LockPersonality="))
1697 return 0;
1698
1699 personality = c->personality;
1700
1701 /* If personality is not specified, use either PER_LINUX or PER_LINUX32 depending on what is currently set. */
1702 if (personality == PERSONALITY_INVALID) {
1703
1704 r = opinionated_personality(&personality);
1705 if (r < 0)
1706 return r;
1707 }
1708
1709 return seccomp_lock_personality(personality);
1710 }
1711
1712 #endif
1713
1714 static int apply_protect_hostname(const Unit *u, const ExecContext *c, int *ret_exit_status) {
1715 assert(u);
1716 assert(c);
1717
1718 if (!c->protect_hostname)
1719 return 0;
1720
1721 if (ns_type_supported(NAMESPACE_UTS)) {
1722 if (unshare(CLONE_NEWUTS) < 0) {
1723 if (!ERRNO_IS_NOT_SUPPORTED(errno) && !ERRNO_IS_PRIVILEGE(errno)) {
1724 *ret_exit_status = EXIT_NAMESPACE;
1725 return log_unit_error_errno(u, errno, "Failed to set up UTS namespacing: %m");
1726 }
1727
1728 log_unit_warning(u, "ProtectHostname=yes is configured, but UTS namespace setup is prohibited (container manager?), ignoring namespace setup.");
1729 }
1730 } else
1731 log_unit_warning(u, "ProtectHostname=yes is configured, but the kernel does not support UTS namespaces, ignoring namespace setup.");
1732
1733 #if HAVE_SECCOMP
1734 int r;
1735
1736 if (skip_seccomp_unavailable(u, "ProtectHostname="))
1737 return 0;
1738
1739 r = seccomp_protect_hostname();
1740 if (r < 0) {
1741 *ret_exit_status = EXIT_SECCOMP;
1742 return log_unit_error_errno(u, r, "Failed to apply hostname restrictions: %m");
1743 }
1744 #endif
1745
1746 return 0;
1747 }
1748
1749 static void do_idle_pipe_dance(int idle_pipe[static 4]) {
1750 assert(idle_pipe);
1751
1752 idle_pipe[1] = safe_close(idle_pipe[1]);
1753 idle_pipe[2] = safe_close(idle_pipe[2]);
1754
1755 if (idle_pipe[0] >= 0) {
1756 int r;
1757
1758 r = fd_wait_for_event(idle_pipe[0], POLLHUP, IDLE_TIMEOUT_USEC);
1759
1760 if (idle_pipe[3] >= 0 && r == 0 /* timeout */) {
1761 ssize_t n;
1762
1763 /* Signal systemd that we are bored and want to continue. */
1764 n = write(idle_pipe[3], "x", 1);
1765 if (n > 0)
1766 /* Wait for systemd to react to the signal above. */
1767 (void) fd_wait_for_event(idle_pipe[0], POLLHUP, IDLE_TIMEOUT2_USEC);
1768 }
1769
1770 idle_pipe[0] = safe_close(idle_pipe[0]);
1771
1772 }
1773
1774 idle_pipe[3] = safe_close(idle_pipe[3]);
1775 }
1776
1777 static const char *exec_directory_env_name_to_string(ExecDirectoryType t);
1778
1779 static int build_environment(
1780 const Unit *u,
1781 const ExecContext *c,
1782 const ExecParameters *p,
1783 size_t n_fds,
1784 const char *home,
1785 const char *username,
1786 const char *shell,
1787 dev_t journal_stream_dev,
1788 ino_t journal_stream_ino,
1789 char ***ret) {
1790
1791 _cleanup_strv_free_ char **our_env = NULL;
1792 size_t n_env = 0;
1793 char *x;
1794
1795 assert(u);
1796 assert(c);
1797 assert(p);
1798 assert(ret);
1799
1800 #define N_ENV_VARS 17
1801 our_env = new0(char*, N_ENV_VARS + _EXEC_DIRECTORY_TYPE_MAX);
1802 if (!our_env)
1803 return -ENOMEM;
1804
1805 if (n_fds > 0) {
1806 _cleanup_free_ char *joined = NULL;
1807
1808 if (asprintf(&x, "LISTEN_PID="PID_FMT, getpid_cached()) < 0)
1809 return -ENOMEM;
1810 our_env[n_env++] = x;
1811
1812 if (asprintf(&x, "LISTEN_FDS=%zu", n_fds) < 0)
1813 return -ENOMEM;
1814 our_env[n_env++] = x;
1815
1816 joined = strv_join(p->fd_names, ":");
1817 if (!joined)
1818 return -ENOMEM;
1819
1820 x = strjoin("LISTEN_FDNAMES=", joined);
1821 if (!x)
1822 return -ENOMEM;
1823 our_env[n_env++] = x;
1824 }
1825
1826 if ((p->flags & EXEC_SET_WATCHDOG) && p->watchdog_usec > 0) {
1827 if (asprintf(&x, "WATCHDOG_PID="PID_FMT, getpid_cached()) < 0)
1828 return -ENOMEM;
1829 our_env[n_env++] = x;
1830
1831 if (asprintf(&x, "WATCHDOG_USEC="USEC_FMT, p->watchdog_usec) < 0)
1832 return -ENOMEM;
1833 our_env[n_env++] = x;
1834 }
1835
1836 /* If this is D-Bus, tell the nss-systemd module, since it relies on being able to use D-Bus look up dynamic
1837 * users via PID 1, possibly dead-locking the dbus daemon. This way it will not use D-Bus to resolve names, but
1838 * check the database directly. */
1839 if (p->flags & EXEC_NSS_BYPASS_BUS) {
1840 x = strdup("SYSTEMD_NSS_BYPASS_BUS=1");
1841 if (!x)
1842 return -ENOMEM;
1843 our_env[n_env++] = x;
1844 }
1845
1846 if (home) {
1847 x = strjoin("HOME=", home);
1848 if (!x)
1849 return -ENOMEM;
1850
1851 path_simplify(x + 5);
1852 our_env[n_env++] = x;
1853 }
1854
1855 if (username) {
1856 x = strjoin("LOGNAME=", username);
1857 if (!x)
1858 return -ENOMEM;
1859 our_env[n_env++] = x;
1860
1861 x = strjoin("USER=", username);
1862 if (!x)
1863 return -ENOMEM;
1864 our_env[n_env++] = x;
1865 }
1866
1867 if (shell) {
1868 x = strjoin("SHELL=", shell);
1869 if (!x)
1870 return -ENOMEM;
1871
1872 path_simplify(x + 6);
1873 our_env[n_env++] = x;
1874 }
1875
1876 if (!sd_id128_is_null(u->invocation_id)) {
1877 if (asprintf(&x, "INVOCATION_ID=" SD_ID128_FORMAT_STR, SD_ID128_FORMAT_VAL(u->invocation_id)) < 0)
1878 return -ENOMEM;
1879
1880 our_env[n_env++] = x;
1881 }
1882
1883 if (exec_context_needs_term(c)) {
1884 const char *tty_path, *term = NULL;
1885
1886 tty_path = exec_context_tty_path(c);
1887
1888 /* If we are forked off PID 1 and we are supposed to operate on /dev/console, then let's try
1889 * to inherit the $TERM set for PID 1. This is useful for containers so that the $TERM the
1890 * container manager passes to PID 1 ends up all the way in the console login shown. */
1891
1892 if (path_equal_ptr(tty_path, "/dev/console") && getppid() == 1)
1893 term = getenv("TERM");
1894
1895 if (!term)
1896 term = default_term_for_tty(tty_path);
1897
1898 x = strjoin("TERM=", term);
1899 if (!x)
1900 return -ENOMEM;
1901 our_env[n_env++] = x;
1902 }
1903
1904 if (journal_stream_dev != 0 && journal_stream_ino != 0) {
1905 if (asprintf(&x, "JOURNAL_STREAM=" DEV_FMT ":" INO_FMT, journal_stream_dev, journal_stream_ino) < 0)
1906 return -ENOMEM;
1907
1908 our_env[n_env++] = x;
1909 }
1910
1911 if (c->log_namespace) {
1912 x = strjoin("LOG_NAMESPACE=", c->log_namespace);
1913 if (!x)
1914 return -ENOMEM;
1915
1916 our_env[n_env++] = x;
1917 }
1918
1919 for (ExecDirectoryType t = 0; t < _EXEC_DIRECTORY_TYPE_MAX; t++) {
1920 _cleanup_free_ char *pre = NULL, *joined = NULL;
1921 const char *n;
1922
1923 if (!p->prefix[t])
1924 continue;
1925
1926 if (strv_isempty(c->directories[t].paths))
1927 continue;
1928
1929 n = exec_directory_env_name_to_string(t);
1930 if (!n)
1931 continue;
1932
1933 pre = strjoin(p->prefix[t], "/");
1934 if (!pre)
1935 return -ENOMEM;
1936
1937 joined = strv_join_full(c->directories[t].paths, ":", pre, true);
1938 if (!joined)
1939 return -ENOMEM;
1940
1941 x = strjoin(n, "=", joined);
1942 if (!x)
1943 return -ENOMEM;
1944
1945 our_env[n_env++] = x;
1946 }
1947
1948 if (exec_context_has_credentials(c) && p->prefix[EXEC_DIRECTORY_RUNTIME]) {
1949 x = strjoin("CREDENTIALS_DIRECTORY=", p->prefix[EXEC_DIRECTORY_RUNTIME], "/credentials/", u->id);
1950 if (!x)
1951 return -ENOMEM;
1952
1953 our_env[n_env++] = x;
1954 }
1955
1956 if (asprintf(&x, "SYSTEMD_EXEC_PID=" PID_FMT, getpid_cached()) < 0)
1957 return -ENOMEM;
1958
1959 our_env[n_env++] = x;
1960
1961 our_env[n_env++] = NULL;
1962 assert(n_env <= N_ENV_VARS + _EXEC_DIRECTORY_TYPE_MAX);
1963 #undef N_ENV_VARS
1964
1965 *ret = TAKE_PTR(our_env);
1966
1967 return 0;
1968 }
1969
1970 static int build_pass_environment(const ExecContext *c, char ***ret) {
1971 _cleanup_strv_free_ char **pass_env = NULL;
1972 size_t n_env = 0;
1973 char **i;
1974
1975 STRV_FOREACH(i, c->pass_environment) {
1976 _cleanup_free_ char *x = NULL;
1977 char *v;
1978
1979 v = getenv(*i);
1980 if (!v)
1981 continue;
1982 x = strjoin(*i, "=", v);
1983 if (!x)
1984 return -ENOMEM;
1985
1986 if (!GREEDY_REALLOC(pass_env, n_env + 2))
1987 return -ENOMEM;
1988
1989 pass_env[n_env++] = TAKE_PTR(x);
1990 pass_env[n_env] = NULL;
1991 }
1992
1993 *ret = TAKE_PTR(pass_env);
1994
1995 return 0;
1996 }
1997
1998 bool exec_needs_mount_namespace(
1999 const ExecContext *context,
2000 const ExecParameters *params,
2001 const ExecRuntime *runtime) {
2002
2003 assert(context);
2004
2005 if (context->root_image)
2006 return true;
2007
2008 if (!strv_isempty(context->read_write_paths) ||
2009 !strv_isempty(context->read_only_paths) ||
2010 !strv_isempty(context->inaccessible_paths) ||
2011 !strv_isempty(context->exec_paths) ||
2012 !strv_isempty(context->no_exec_paths))
2013 return true;
2014
2015 if (context->n_bind_mounts > 0)
2016 return true;
2017
2018 if (context->n_temporary_filesystems > 0)
2019 return true;
2020
2021 if (context->n_mount_images > 0)
2022 return true;
2023
2024 if (context->n_extension_images > 0)
2025 return true;
2026
2027 if (!IN_SET(context->mount_flags, 0, MS_SHARED))
2028 return true;
2029
2030 if (context->private_tmp && runtime && (runtime->tmp_dir || runtime->var_tmp_dir))
2031 return true;
2032
2033 if (context->private_devices ||
2034 context->private_mounts ||
2035 context->protect_system != PROTECT_SYSTEM_NO ||
2036 context->protect_home != PROTECT_HOME_NO ||
2037 context->protect_kernel_tunables ||
2038 context->protect_kernel_modules ||
2039 context->protect_kernel_logs ||
2040 context->protect_control_groups ||
2041 context->protect_proc != PROTECT_PROC_DEFAULT ||
2042 context->proc_subset != PROC_SUBSET_ALL ||
2043 context->private_ipc ||
2044 context->ipc_namespace_path)
2045 return true;
2046
2047 if (context->root_directory) {
2048 if (exec_context_get_effective_mount_apivfs(context))
2049 return true;
2050
2051 for (ExecDirectoryType t = 0; t < _EXEC_DIRECTORY_TYPE_MAX; t++) {
2052 if (params && !params->prefix[t])
2053 continue;
2054
2055 if (!strv_isempty(context->directories[t].paths))
2056 return true;
2057 }
2058 }
2059
2060 if (context->dynamic_user &&
2061 (!strv_isempty(context->directories[EXEC_DIRECTORY_STATE].paths) ||
2062 !strv_isempty(context->directories[EXEC_DIRECTORY_CACHE].paths) ||
2063 !strv_isempty(context->directories[EXEC_DIRECTORY_LOGS].paths)))
2064 return true;
2065
2066 if (context->log_namespace)
2067 return true;
2068
2069 return false;
2070 }
2071
2072 static int setup_private_users(uid_t ouid, gid_t ogid, uid_t uid, gid_t gid) {
2073 _cleanup_free_ char *uid_map = NULL, *gid_map = NULL;
2074 _cleanup_close_pair_ int errno_pipe[2] = { -1, -1 };
2075 _cleanup_close_ int unshare_ready_fd = -1;
2076 _cleanup_(sigkill_waitp) pid_t pid = 0;
2077 uint64_t c = 1;
2078 ssize_t n;
2079 int r;
2080
2081 /* Set up a user namespace and map the original UID/GID (IDs from before any user or group changes, i.e.
2082 * the IDs from the user or system manager(s)) to itself, the selected UID/GID to itself, and everything else to
2083 * nobody. In order to be able to write this mapping we need CAP_SETUID in the original user namespace, which
2084 * we however lack after opening the user namespace. To work around this we fork() a temporary child process,
2085 * which waits for the parent to create the new user namespace while staying in the original namespace. The
2086 * child then writes the UID mapping, under full privileges. The parent waits for the child to finish and
2087 * continues execution normally.
2088 * For unprivileged users (i.e. without capabilities), the root to root mapping is excluded. As such, it
2089 * does not need CAP_SETUID to write the single line mapping to itself. */
2090
2091 /* Can only set up multiple mappings with CAP_SETUID. */
2092 if (have_effective_cap(CAP_SETUID) && uid != ouid && uid_is_valid(uid))
2093 r = asprintf(&uid_map,
2094 UID_FMT " " UID_FMT " 1\n" /* Map $OUID → $OUID */
2095 UID_FMT " " UID_FMT " 1\n", /* Map $UID → $UID */
2096 ouid, ouid, uid, uid);
2097 else
2098 r = asprintf(&uid_map,
2099 UID_FMT " " UID_FMT " 1\n", /* Map $OUID → $OUID */
2100 ouid, ouid);
2101
2102 if (r < 0)
2103 return -ENOMEM;
2104
2105 /* Can only set up multiple mappings with CAP_SETGID. */
2106 if (have_effective_cap(CAP_SETGID) && gid != ogid && gid_is_valid(gid))
2107 r = asprintf(&gid_map,
2108 GID_FMT " " GID_FMT " 1\n" /* Map $OGID → $OGID */
2109 GID_FMT " " GID_FMT " 1\n", /* Map $GID → $GID */
2110 ogid, ogid, gid, gid);
2111 else
2112 r = asprintf(&gid_map,
2113 GID_FMT " " GID_FMT " 1\n", /* Map $OGID -> $OGID */
2114 ogid, ogid);
2115
2116 if (r < 0)
2117 return -ENOMEM;
2118
2119 /* Create a communication channel so that the parent can tell the child when it finished creating the user
2120 * namespace. */
2121 unshare_ready_fd = eventfd(0, EFD_CLOEXEC);
2122 if (unshare_ready_fd < 0)
2123 return -errno;
2124
2125 /* Create a communication channel so that the child can tell the parent a proper error code in case it
2126 * failed. */
2127 if (pipe2(errno_pipe, O_CLOEXEC) < 0)
2128 return -errno;
2129
2130 r = safe_fork("(sd-userns)", FORK_RESET_SIGNALS|FORK_DEATHSIG, &pid);
2131 if (r < 0)
2132 return r;
2133 if (r == 0) {
2134 _cleanup_close_ int fd = -1;
2135 const char *a;
2136 pid_t ppid;
2137
2138 /* Child process, running in the original user namespace. Let's update the parent's UID/GID map from
2139 * here, after the parent opened its own user namespace. */
2140
2141 ppid = getppid();
2142 errno_pipe[0] = safe_close(errno_pipe[0]);
2143
2144 /* Wait until the parent unshared the user namespace */
2145 if (read(unshare_ready_fd, &c, sizeof(c)) < 0) {
2146 r = -errno;
2147 goto child_fail;
2148 }
2149
2150 /* Disable the setgroups() system call in the child user namespace, for good. */
2151 a = procfs_file_alloca(ppid, "setgroups");
2152 fd = open(a, O_WRONLY|O_CLOEXEC);
2153 if (fd < 0) {
2154 if (errno != ENOENT) {
2155 r = -errno;
2156 goto child_fail;
2157 }
2158
2159 /* If the file is missing the kernel is too old, let's continue anyway. */
2160 } else {
2161 if (write(fd, "deny\n", 5) < 0) {
2162 r = -errno;
2163 goto child_fail;
2164 }
2165
2166 fd = safe_close(fd);
2167 }
2168
2169 /* First write the GID map */
2170 a = procfs_file_alloca(ppid, "gid_map");
2171 fd = open(a, O_WRONLY|O_CLOEXEC);
2172 if (fd < 0) {
2173 r = -errno;
2174 goto child_fail;
2175 }
2176 if (write(fd, gid_map, strlen(gid_map)) < 0) {
2177 r = -errno;
2178 goto child_fail;
2179 }
2180 fd = safe_close(fd);
2181
2182 /* The write the UID map */
2183 a = procfs_file_alloca(ppid, "uid_map");
2184 fd = open(a, O_WRONLY|O_CLOEXEC);
2185 if (fd < 0) {
2186 r = -errno;
2187 goto child_fail;
2188 }
2189 if (write(fd, uid_map, strlen(uid_map)) < 0) {
2190 r = -errno;
2191 goto child_fail;
2192 }
2193
2194 _exit(EXIT_SUCCESS);
2195
2196 child_fail:
2197 (void) write(errno_pipe[1], &r, sizeof(r));
2198 _exit(EXIT_FAILURE);
2199 }
2200
2201 errno_pipe[1] = safe_close(errno_pipe[1]);
2202
2203 if (unshare(CLONE_NEWUSER) < 0)
2204 return -errno;
2205
2206 /* Let the child know that the namespace is ready now */
2207 if (write(unshare_ready_fd, &c, sizeof(c)) < 0)
2208 return -errno;
2209
2210 /* Try to read an error code from the child */
2211 n = read(errno_pipe[0], &r, sizeof(r));
2212 if (n < 0)
2213 return -errno;
2214 if (n == sizeof(r)) { /* an error code was sent to us */
2215 if (r < 0)
2216 return r;
2217 return -EIO;
2218 }
2219 if (n != 0) /* on success we should have read 0 bytes */
2220 return -EIO;
2221
2222 r = wait_for_terminate_and_check("(sd-userns)", pid, 0);
2223 pid = 0;
2224 if (r < 0)
2225 return r;
2226 if (r != EXIT_SUCCESS) /* If something strange happened with the child, let's consider this fatal, too */
2227 return -EIO;
2228
2229 return 0;
2230 }
2231
2232 static bool exec_directory_is_private(const ExecContext *context, ExecDirectoryType type) {
2233 if (!context->dynamic_user)
2234 return false;
2235
2236 if (type == EXEC_DIRECTORY_CONFIGURATION)
2237 return false;
2238
2239 if (type == EXEC_DIRECTORY_RUNTIME && context->runtime_directory_preserve_mode == EXEC_PRESERVE_NO)
2240 return false;
2241
2242 return true;
2243 }
2244
2245 static int setup_exec_directory(
2246 const ExecContext *context,
2247 const ExecParameters *params,
2248 uid_t uid,
2249 gid_t gid,
2250 ExecDirectoryType type,
2251 int *exit_status) {
2252
2253 static const int exit_status_table[_EXEC_DIRECTORY_TYPE_MAX] = {
2254 [EXEC_DIRECTORY_RUNTIME] = EXIT_RUNTIME_DIRECTORY,
2255 [EXEC_DIRECTORY_STATE] = EXIT_STATE_DIRECTORY,
2256 [EXEC_DIRECTORY_CACHE] = EXIT_CACHE_DIRECTORY,
2257 [EXEC_DIRECTORY_LOGS] = EXIT_LOGS_DIRECTORY,
2258 [EXEC_DIRECTORY_CONFIGURATION] = EXIT_CONFIGURATION_DIRECTORY,
2259 };
2260 char **rt;
2261 int r;
2262
2263 assert(context);
2264 assert(params);
2265 assert(type >= 0 && type < _EXEC_DIRECTORY_TYPE_MAX);
2266 assert(exit_status);
2267
2268 if (!params->prefix[type])
2269 return 0;
2270
2271 if (params->flags & EXEC_CHOWN_DIRECTORIES) {
2272 if (!uid_is_valid(uid))
2273 uid = 0;
2274 if (!gid_is_valid(gid))
2275 gid = 0;
2276 }
2277
2278 STRV_FOREACH(rt, context->directories[type].paths) {
2279 _cleanup_free_ char *p = NULL, *pp = NULL;
2280
2281 p = path_join(params->prefix[type], *rt);
2282 if (!p) {
2283 r = -ENOMEM;
2284 goto fail;
2285 }
2286
2287 r = mkdir_parents_label(p, 0755);
2288 if (r < 0)
2289 goto fail;
2290
2291 if (exec_directory_is_private(context, type)) {
2292 /* So, here's one extra complication when dealing with DynamicUser=1 units. In that
2293 * case we want to avoid leaving a directory around fully accessible that is owned by
2294 * a dynamic user whose UID is later on reused. To lock this down we use the same
2295 * trick used by container managers to prohibit host users to get access to files of
2296 * the same UID in containers: we place everything inside a directory that has an
2297 * access mode of 0700 and is owned root:root, so that it acts as security boundary
2298 * for unprivileged host code. We then use fs namespacing to make this directory
2299 * permeable for the service itself.
2300 *
2301 * Specifically: for a service which wants a special directory "foo/" we first create
2302 * a directory "private/" with access mode 0700 owned by root:root. Then we place
2303 * "foo" inside of that directory (i.e. "private/foo/"), and make "foo" a symlink to
2304 * "private/foo". This way, privileged host users can access "foo/" as usual, but
2305 * unprivileged host users can't look into it. Inside of the namespace of the unit
2306 * "private/" is replaced by a more liberally accessible tmpfs, into which the host's
2307 * "private/foo/" is mounted under the same name, thus disabling the access boundary
2308 * for the service and making sure it only gets access to the dirs it needs but no
2309 * others. Tricky? Yes, absolutely, but it works!
2310 *
2311 * Note that we don't do this for EXEC_DIRECTORY_CONFIGURATION as that's assumed not
2312 * to be owned by the service itself.
2313 *
2314 * Also, note that we don't do this for EXEC_DIRECTORY_RUNTIME as that's often used
2315 * for sharing files or sockets with other services. */
2316
2317 pp = path_join(params->prefix[type], "private");
2318 if (!pp) {
2319 r = -ENOMEM;
2320 goto fail;
2321 }
2322
2323 /* First set up private root if it doesn't exist yet, with access mode 0700 and owned by root:root */
2324 r = mkdir_safe_label(pp, 0700, 0, 0, MKDIR_WARN_MODE);
2325 if (r < 0)
2326 goto fail;
2327
2328 if (!path_extend(&pp, *rt)) {
2329 r = -ENOMEM;
2330 goto fail;
2331 }
2332
2333 /* Create all directories between the configured directory and this private root, and mark them 0755 */
2334 r = mkdir_parents_label(pp, 0755);
2335 if (r < 0)
2336 goto fail;
2337
2338 if (is_dir(p, false) > 0 &&
2339 (laccess(pp, F_OK) < 0 && errno == ENOENT)) {
2340
2341 /* Hmm, the private directory doesn't exist yet, but the normal one exists? If so, move
2342 * it over. Most likely the service has been upgraded from one that didn't use
2343 * DynamicUser=1, to one that does. */
2344
2345 log_info("Found pre-existing public %s= directory %s, migrating to %s.\n"
2346 "Apparently, service previously had DynamicUser= turned off, and has now turned it on.",
2347 exec_directory_type_to_string(type), p, pp);
2348
2349 if (rename(p, pp) < 0) {
2350 r = -errno;
2351 goto fail;
2352 }
2353 } else {
2354 /* Otherwise, create the actual directory for the service */
2355
2356 r = mkdir_label(pp, context->directories[type].mode);
2357 if (r < 0 && r != -EEXIST)
2358 goto fail;
2359 }
2360
2361 /* And link it up from the original place */
2362 r = symlink_idempotent(pp, p, true);
2363 if (r < 0)
2364 goto fail;
2365
2366 } else {
2367 _cleanup_free_ char *target = NULL;
2368
2369 if (type != EXEC_DIRECTORY_CONFIGURATION &&
2370 readlink_and_make_absolute(p, &target) >= 0) {
2371 _cleanup_free_ char *q = NULL, *q_resolved = NULL, *target_resolved = NULL;
2372
2373 /* This already exists and is a symlink? Interesting. Maybe it's one created
2374 * by DynamicUser=1 (see above)?
2375 *
2376 * We do this for all directory types except for ConfigurationDirectory=,
2377 * since they all support the private/ symlink logic at least in some
2378 * configurations, see above. */
2379
2380 r = chase_symlinks(target, NULL, 0, &target_resolved, NULL);
2381 if (r < 0)
2382 goto fail;
2383
2384 q = path_join(params->prefix[type], "private", *rt);
2385 if (!q) {
2386 r = -ENOMEM;
2387 goto fail;
2388 }
2389
2390 /* /var/lib or friends may be symlinks. So, let's chase them also. */
2391 r = chase_symlinks(q, NULL, CHASE_NONEXISTENT, &q_resolved, NULL);
2392 if (r < 0)
2393 goto fail;
2394
2395 if (path_equal(q_resolved, target_resolved)) {
2396
2397 /* Hmm, apparently DynamicUser= was once turned on for this service,
2398 * but is no longer. Let's move the directory back up. */
2399
2400 log_info("Found pre-existing private %s= directory %s, migrating to %s.\n"
2401 "Apparently, service previously had DynamicUser= turned on, and has now turned it off.",
2402 exec_directory_type_to_string(type), q, p);
2403
2404 if (unlink(p) < 0) {
2405 r = -errno;
2406 goto fail;
2407 }
2408
2409 if (rename(q, p) < 0) {
2410 r = -errno;
2411 goto fail;
2412 }
2413 }
2414 }
2415
2416 r = mkdir_label(p, context->directories[type].mode);
2417 if (r < 0) {
2418 if (r != -EEXIST)
2419 goto fail;
2420
2421 if (type == EXEC_DIRECTORY_CONFIGURATION) {
2422 struct stat st;
2423
2424 /* Don't change the owner/access mode of the configuration directory,
2425 * as in the common case it is not written to by a service, and shall
2426 * not be writable. */
2427
2428 if (stat(p, &st) < 0) {
2429 r = -errno;
2430 goto fail;
2431 }
2432
2433 /* Still complain if the access mode doesn't match */
2434 if (((st.st_mode ^ context->directories[type].mode) & 07777) != 0)
2435 log_warning("%s \'%s\' already exists but the mode is different. "
2436 "(File system: %o %sMode: %o)",
2437 exec_directory_type_to_string(type), *rt,
2438 st.st_mode & 07777, exec_directory_type_to_string(type), context->directories[type].mode & 07777);
2439
2440 continue;
2441 }
2442 }
2443 }
2444
2445 /* Lock down the access mode (we use chmod_and_chown() to make this idempotent. We don't
2446 * specify UID/GID here, so that path_chown_recursive() can optimize things depending on the
2447 * current UID/GID ownership.) */
2448 r = chmod_and_chown(pp ?: p, context->directories[type].mode, UID_INVALID, GID_INVALID);
2449 if (r < 0)
2450 goto fail;
2451
2452 /* Then, change the ownership of the whole tree, if necessary. When dynamic users are used we
2453 * drop the suid/sgid bits, since we really don't want SUID/SGID files for dynamic UID/GID
2454 * assignments to exist. */
2455 r = path_chown_recursive(pp ?: p, uid, gid, context->dynamic_user ? 01777 : 07777);
2456 if (r < 0)
2457 goto fail;
2458 }
2459
2460 return 0;
2461
2462 fail:
2463 *exit_status = exit_status_table[type];
2464 return r;
2465 }
2466
2467 static int write_credential(
2468 int dfd,
2469 const char *id,
2470 const void *data,
2471 size_t size,
2472 uid_t uid,
2473 bool ownership_ok) {
2474
2475 _cleanup_(unlink_and_freep) char *tmp = NULL;
2476 _cleanup_close_ int fd = -1;
2477 int r;
2478
2479 r = tempfn_random_child("", "cred", &tmp);
2480 if (r < 0)
2481 return r;
2482
2483 fd = openat(dfd, tmp, O_CREAT|O_RDWR|O_CLOEXEC|O_EXCL|O_NOFOLLOW|O_NOCTTY, 0600);
2484 if (fd < 0) {
2485 tmp = mfree(tmp);
2486 return -errno;
2487 }
2488
2489 r = loop_write(fd, data, size, /* do_pool = */ false);
2490 if (r < 0)
2491 return r;
2492
2493 if (fchmod(fd, 0400) < 0) /* Take away "w" bit */
2494 return -errno;
2495
2496 if (uid_is_valid(uid) && uid != getuid()) {
2497 r = fd_add_uid_acl_permission(fd, uid, ACL_READ);
2498 if (r < 0) {
2499 if (!ERRNO_IS_NOT_SUPPORTED(r) && !ERRNO_IS_PRIVILEGE(r))
2500 return r;
2501
2502 if (!ownership_ok) /* Ideally we use ACLs, since we can neatly express what we want
2503 * to express: that the user gets read access and nothing
2504 * else. But if the backing fs can't support that (e.g. ramfs)
2505 * then we can use file ownership instead. But that's only safe if
2506 * we can then re-mount the whole thing read-only, so that the
2507 * user can no longer chmod() the file to gain write access. */
2508 return r;
2509
2510 if (fchown(fd, uid, GID_INVALID) < 0)
2511 return -errno;
2512 }
2513 }
2514
2515 if (renameat(dfd, tmp, dfd, id) < 0)
2516 return -errno;
2517
2518 tmp = mfree(tmp);
2519 return 0;
2520 }
2521
2522 #define CREDENTIALS_BYTES_MAX (1024LU * 1024LU) /* Refuse to pass more than 1M, after all this is unswappable memory */
2523
2524 static int acquire_credentials(
2525 const ExecContext *context,
2526 const ExecParameters *params,
2527 const char *unit,
2528 const char *p,
2529 uid_t uid,
2530 bool ownership_ok) {
2531
2532 uint64_t left = CREDENTIALS_BYTES_MAX;
2533 _cleanup_close_ int dfd = -1;
2534 ExecSetCredential *sc;
2535 char **id, **fn;
2536 int r;
2537
2538 assert(context);
2539 assert(p);
2540
2541 dfd = open(p, O_DIRECTORY|O_CLOEXEC);
2542 if (dfd < 0)
2543 return -errno;
2544
2545 /* First we use the literally specified credentials. Note that they might be overridden again below,
2546 * and thus act as a "default" if the same credential is specified multiple times */
2547 HASHMAP_FOREACH(sc, context->set_credentials) {
2548 size_t add;
2549
2550 add = strlen(sc->id) + sc->size;
2551 if (add > left)
2552 return -E2BIG;
2553
2554 r = write_credential(dfd, sc->id, sc->data, sc->size, uid, ownership_ok);
2555 if (r < 0)
2556 return r;
2557
2558 left -= add;
2559 }
2560
2561 /* Then, load credential off disk (or acquire via AF_UNIX socket) */
2562 STRV_FOREACH_PAIR(id, fn, context->load_credentials) {
2563 ReadFullFileFlags flags = READ_FULL_FILE_SECURE;
2564 _cleanup_(erase_and_freep) char *data = NULL;
2565 _cleanup_free_ char *j = NULL, *bindname = NULL;
2566 bool missing_ok = true;
2567 const char *source;
2568 size_t size, add;
2569
2570 if (path_is_absolute(*fn)) {
2571 /* If this is an absolute path, read the data directly from it, and support AF_UNIX sockets */
2572 source = *fn;
2573 flags |= READ_FULL_FILE_CONNECT_SOCKET;
2574
2575 /* Pass some minimal info about the unit and the credential name we are looking to acquire
2576 * via the source socket address in case we read off an AF_UNIX socket. */
2577 if (asprintf(&bindname, "@%" PRIx64"/unit/%s/%s", random_u64(), unit, *id) < 0)
2578 return -ENOMEM;
2579
2580 missing_ok = false;
2581
2582 } else if (params->received_credentials) {
2583 /* If this is a relative path, take it relative to the credentials we received
2584 * ourselves. We don't support the AF_UNIX stuff in this mode, since we are operating
2585 * on a credential store, i.e. this is guaranteed to be regular files. */
2586 j = path_join(params->received_credentials, *fn);
2587 if (!j)
2588 return -ENOMEM;
2589
2590 source = j;
2591 } else
2592 source = NULL;
2593
2594 if (source)
2595 r = read_full_file_full(AT_FDCWD, source, UINT64_MAX, SIZE_MAX, flags, bindname, &data, &size);
2596 else
2597 r = -ENOENT;
2598 if (r == -ENOENT && (missing_ok || faccessat(dfd, *id, F_OK, AT_SYMLINK_NOFOLLOW) >= 0)) {
2599 /* Make a missing inherited credential non-fatal, let's just continue. After all apps
2600 * will get clear errors if we don't pass such a missing credential on as they
2601 * themselves will get ENOENT when trying to read them, which should not be much
2602 * worse than when we handle the error here and make it fatal.
2603 *
2604 * Also, if the source file doesn't exist, but we already acquired the key otherwise,
2605 * then don't fail either. */
2606 log_debug_errno(r, "Couldn't read inherited credential '%s', skipping: %m", *fn);
2607 continue;
2608 }
2609 if (r < 0)
2610 return log_debug_errno(r, "Failed to read credential '%s': %m", *fn);
2611
2612 add = strlen(*id) + size;
2613 if (add > left)
2614 return -E2BIG;
2615
2616 r = write_credential(dfd, *id, data, size, uid, ownership_ok);
2617 if (r < 0)
2618 return r;
2619
2620 left -= add;
2621 }
2622
2623 if (fchmod(dfd, 0500) < 0) /* Now take away the "w" bit */
2624 return -errno;
2625
2626 /* After we created all keys with the right perms, also make sure the credential store as a whole is
2627 * accessible */
2628
2629 if (uid_is_valid(uid) && uid != getuid()) {
2630 r = fd_add_uid_acl_permission(dfd, uid, ACL_READ | ACL_EXECUTE);
2631 if (r < 0) {
2632 if (!ERRNO_IS_NOT_SUPPORTED(r) && !ERRNO_IS_PRIVILEGE(r))
2633 return r;
2634
2635 if (!ownership_ok)
2636 return r;
2637
2638 if (fchown(dfd, uid, GID_INVALID) < 0)
2639 return -errno;
2640 }
2641 }
2642
2643 return 0;
2644 }
2645
2646 static int setup_credentials_internal(
2647 const ExecContext *context,
2648 const ExecParameters *params,
2649 const char *unit,
2650 const char *final, /* This is where the credential store shall eventually end up at */
2651 const char *workspace, /* This is where we can prepare it before moving it to the final place */
2652 bool reuse_workspace, /* Whether to reuse any existing workspace mount if it already is a mount */
2653 bool must_mount, /* Whether to require that we mount something, it's not OK to use the plain directory fall back */
2654 uid_t uid) {
2655
2656 int r, workspace_mounted; /* negative if we don't know yet whether we have/can mount something; true
2657 * if we mounted something; false if we definitely can't mount anything */
2658 bool final_mounted;
2659 const char *where;
2660
2661 assert(context);
2662 assert(final);
2663 assert(workspace);
2664
2665 if (reuse_workspace) {
2666 r = path_is_mount_point(workspace, NULL, 0);
2667 if (r < 0)
2668 return r;
2669 if (r > 0)
2670 workspace_mounted = true; /* If this is already a mount, and we are supposed to reuse it, let's keep this in mind */
2671 else
2672 workspace_mounted = -1; /* We need to figure out if we can mount something to the workspace */
2673 } else
2674 workspace_mounted = -1; /* ditto */
2675
2676 r = path_is_mount_point(final, NULL, 0);
2677 if (r < 0)
2678 return r;
2679 if (r > 0) {
2680 /* If the final place already has something mounted, we use that. If the workspace also has
2681 * something mounted we assume it's actually the same mount (but with MS_RDONLY
2682 * different). */
2683 final_mounted = true;
2684
2685 if (workspace_mounted < 0) {
2686 /* If the final place is mounted, but the workspace we isn't, then let's bind mount
2687 * the final version to the workspace, and make it writable, so that we can make
2688 * changes */
2689
2690 r = mount_nofollow_verbose(LOG_DEBUG, final, workspace, NULL, MS_BIND|MS_REC, NULL);
2691 if (r < 0)
2692 return r;
2693
2694 r = mount_nofollow_verbose(LOG_DEBUG, NULL, workspace, NULL, MS_BIND|MS_REMOUNT|MS_NODEV|MS_NOEXEC|MS_NOSUID, NULL);
2695 if (r < 0)
2696 return r;
2697
2698 workspace_mounted = true;
2699 }
2700 } else
2701 final_mounted = false;
2702
2703 if (workspace_mounted < 0) {
2704 /* Nothing is mounted on the workspace yet, let's try to mount something now */
2705 for (int try = 0;; try++) {
2706
2707 if (try == 0) {
2708 /* Try "ramfs" first, since it's not swap backed */
2709 r = mount_nofollow_verbose(LOG_DEBUG, "ramfs", workspace, "ramfs", MS_NODEV|MS_NOEXEC|MS_NOSUID, "mode=0700");
2710 if (r >= 0) {
2711 workspace_mounted = true;
2712 break;
2713 }
2714
2715 } else if (try == 1) {
2716 _cleanup_free_ char *opts = NULL;
2717
2718 if (asprintf(&opts, "mode=0700,nr_inodes=1024,size=%lu", CREDENTIALS_BYTES_MAX) < 0)
2719 return -ENOMEM;
2720
2721 /* Fall back to "tmpfs" otherwise */
2722 r = mount_nofollow_verbose(LOG_DEBUG, "tmpfs", workspace, "tmpfs", MS_NODEV|MS_NOEXEC|MS_NOSUID, opts);
2723 if (r >= 0) {
2724 workspace_mounted = true;
2725 break;
2726 }
2727
2728 } else {
2729 /* If that didn't work, try to make a bind mount from the final to the workspace, so that we can make it writable there. */
2730 r = mount_nofollow_verbose(LOG_DEBUG, final, workspace, NULL, MS_BIND|MS_REC, NULL);
2731 if (r < 0) {
2732 if (!ERRNO_IS_PRIVILEGE(r)) /* Propagate anything that isn't a permission problem */
2733 return r;
2734
2735 if (must_mount) /* If we it's not OK to use the plain directory
2736 * fallback, propagate all errors too */
2737 return r;
2738
2739 /* If we lack privileges to bind mount stuff, then let's gracefully
2740 * proceed for compat with container envs, and just use the final dir
2741 * as is. */
2742
2743 workspace_mounted = false;
2744 break;
2745 }
2746
2747 /* Make the new bind mount writable (i.e. drop MS_RDONLY) */
2748 r = mount_nofollow_verbose(LOG_DEBUG, NULL, workspace, NULL, MS_BIND|MS_REMOUNT|MS_NODEV|MS_NOEXEC|MS_NOSUID, NULL);
2749 if (r < 0)
2750 return r;
2751
2752 workspace_mounted = true;
2753 break;
2754 }
2755 }
2756 }
2757
2758 assert(!must_mount || workspace_mounted > 0);
2759 where = workspace_mounted ? workspace : final;
2760
2761 r = acquire_credentials(context, params, unit, where, uid, workspace_mounted);
2762 if (r < 0)
2763 return r;
2764
2765 if (workspace_mounted) {
2766 /* Make workspace read-only now, so that any bind mount we make from it defaults to read-only too */
2767 r = mount_nofollow_verbose(LOG_DEBUG, NULL, workspace, NULL, MS_BIND|MS_REMOUNT|MS_RDONLY|MS_NODEV|MS_NOEXEC|MS_NOSUID, NULL);
2768 if (r < 0)
2769 return r;
2770
2771 /* And mount it to the final place, read-only */
2772 if (final_mounted)
2773 r = umount_verbose(LOG_DEBUG, workspace, MNT_DETACH|UMOUNT_NOFOLLOW);
2774 else
2775 r = mount_nofollow_verbose(LOG_DEBUG, workspace, final, NULL, MS_MOVE, NULL);
2776 if (r < 0)
2777 return r;
2778 } else {
2779 _cleanup_free_ char *parent = NULL;
2780
2781 /* If we do not have our own mount put used the plain directory fallback, then we need to
2782 * open access to the top-level credential directory and the per-service directory now */
2783
2784 parent = dirname_malloc(final);
2785 if (!parent)
2786 return -ENOMEM;
2787 if (chmod(parent, 0755) < 0)
2788 return -errno;
2789 }
2790
2791 return 0;
2792 }
2793
2794 static int setup_credentials(
2795 const ExecContext *context,
2796 const ExecParameters *params,
2797 const char *unit,
2798 uid_t uid) {
2799
2800 _cleanup_free_ char *p = NULL, *q = NULL;
2801 const char *i;
2802 int r;
2803
2804 assert(context);
2805 assert(params);
2806
2807 if (!exec_context_has_credentials(context))
2808 return 0;
2809
2810 if (!params->prefix[EXEC_DIRECTORY_RUNTIME])
2811 return -EINVAL;
2812
2813 /* This where we'll place stuff when we are done; this main credentials directory is world-readable,
2814 * and the subdir we mount over with a read-only file system readable by the service's user */
2815 q = path_join(params->prefix[EXEC_DIRECTORY_RUNTIME], "credentials");
2816 if (!q)
2817 return -ENOMEM;
2818
2819 r = mkdir_label(q, 0755); /* top-level dir: world readable/searchable */
2820 if (r < 0 && r != -EEXIST)
2821 return r;
2822
2823 p = path_join(q, unit);
2824 if (!p)
2825 return -ENOMEM;
2826
2827 r = mkdir_label(p, 0700); /* per-unit dir: private to user */
2828 if (r < 0 && r != -EEXIST)
2829 return r;
2830
2831 r = safe_fork("(sd-mkdcreds)", FORK_DEATHSIG|FORK_WAIT|FORK_NEW_MOUNTNS, NULL);
2832 if (r < 0) {
2833 _cleanup_free_ char *t = NULL, *u = NULL;
2834
2835 /* If this is not a privilege or support issue then propagate the error */
2836 if (!ERRNO_IS_NOT_SUPPORTED(r) && !ERRNO_IS_PRIVILEGE(r))
2837 return r;
2838
2839 /* Temporary workspace, that remains inaccessible all the time. We prepare stuff there before moving
2840 * it into place, so that users can't access half-initialized credential stores. */
2841 t = path_join(params->prefix[EXEC_DIRECTORY_RUNTIME], "systemd/temporary-credentials");
2842 if (!t)
2843 return -ENOMEM;
2844
2845 /* We can't set up a mount namespace. In that case operate on a fixed, inaccessible per-unit
2846 * directory outside of /run/credentials/ first, and then move it over to /run/credentials/
2847 * after it is fully set up */
2848 u = path_join(t, unit);
2849 if (!u)
2850 return -ENOMEM;
2851
2852 FOREACH_STRING(i, t, u) {
2853 r = mkdir_label(i, 0700);
2854 if (r < 0 && r != -EEXIST)
2855 return r;
2856 }
2857
2858 r = setup_credentials_internal(
2859 context,
2860 params,
2861 unit,
2862 p, /* final mount point */
2863 u, /* temporary workspace to overmount */
2864 true, /* reuse the workspace if it is already a mount */
2865 false, /* it's OK to fall back to a plain directory if we can't mount anything */
2866 uid);
2867
2868 (void) rmdir(u); /* remove the workspace again if we can. */
2869
2870 if (r < 0)
2871 return r;
2872
2873 } else if (r == 0) {
2874
2875 /* We managed to set up a mount namespace, and are now in a child. That's great. In this case
2876 * we can use the same directory for all cases, after turning off propagation. Question
2877 * though is: where do we turn off propagation exactly, and where do we place the workspace
2878 * directory? We need some place that is guaranteed to be a mount point in the host, and
2879 * which is guaranteed to have a subdir we can mount over. /run/ is not suitable for this,
2880 * since we ultimately want to move the resulting file system there, i.e. we need propagation
2881 * for /run/ eventually. We could use our own /run/systemd/bind mount on itself, but that
2882 * would be visible in the host mount table all the time, which we want to avoid. Hence, what
2883 * we do here instead we use /dev/ and /dev/shm/ for our purposes. We know for sure that
2884 * /dev/ is a mount point and we now for sure that /dev/shm/ exists. Hence we can turn off
2885 * propagation on the former, and then overmount the latter.
2886 *
2887 * Yes it's nasty playing games with /dev/ and /dev/shm/ like this, since it does not exist
2888 * for this purpose, but there are few other candidates that work equally well for us, and
2889 * given that the we do this in a privately namespaced short-lived single-threaded process
2890 * that no one else sees this should be OK to do. */
2891
2892 r = mount_nofollow_verbose(LOG_DEBUG, NULL, "/dev", NULL, MS_SLAVE|MS_REC, NULL); /* Turn off propagation from our namespace to host */
2893 if (r < 0)
2894 goto child_fail;
2895
2896 r = setup_credentials_internal(
2897 context,
2898 params,
2899 unit,
2900 p, /* final mount point */
2901 "/dev/shm", /* temporary workspace to overmount */
2902 false, /* do not reuse /dev/shm if it is already a mount, under no circumstances */
2903 true, /* insist that something is mounted, do not allow fallback to plain directory */
2904 uid);
2905 if (r < 0)
2906 goto child_fail;
2907
2908 _exit(EXIT_SUCCESS);
2909
2910 child_fail:
2911 _exit(EXIT_FAILURE);
2912 }
2913
2914 return 0;
2915 }
2916
2917 #if ENABLE_SMACK
2918 static int setup_smack(
2919 const ExecContext *context,
2920 int executable_fd) {
2921 int r;
2922
2923 assert(context);
2924 assert(executable_fd >= 0);
2925
2926 if (context->smack_process_label) {
2927 r = mac_smack_apply_pid(0, context->smack_process_label);
2928 if (r < 0)
2929 return r;
2930 }
2931 #ifdef SMACK_DEFAULT_PROCESS_LABEL
2932 else {
2933 _cleanup_free_ char *exec_label = NULL;
2934
2935 r = mac_smack_read_fd(executable_fd, SMACK_ATTR_EXEC, &exec_label);
2936 if (r < 0 && !IN_SET(r, -ENODATA, -EOPNOTSUPP))
2937 return r;
2938
2939 r = mac_smack_apply_pid(0, exec_label ? : SMACK_DEFAULT_PROCESS_LABEL);
2940 if (r < 0)
2941 return r;
2942 }
2943 #endif
2944
2945 return 0;
2946 }
2947 #endif
2948
2949 static int compile_bind_mounts(
2950 const ExecContext *context,
2951 const ExecParameters *params,
2952 BindMount **ret_bind_mounts,
2953 size_t *ret_n_bind_mounts,
2954 char ***ret_empty_directories) {
2955
2956 _cleanup_strv_free_ char **empty_directories = NULL;
2957 BindMount *bind_mounts;
2958 size_t n, h = 0;
2959 int r;
2960
2961 assert(context);
2962 assert(params);
2963 assert(ret_bind_mounts);
2964 assert(ret_n_bind_mounts);
2965 assert(ret_empty_directories);
2966
2967 n = context->n_bind_mounts;
2968 for (ExecDirectoryType t = 0; t < _EXEC_DIRECTORY_TYPE_MAX; t++) {
2969 if (!params->prefix[t])
2970 continue;
2971
2972 n += strv_length(context->directories[t].paths);
2973 }
2974
2975 if (n <= 0) {
2976 *ret_bind_mounts = NULL;
2977 *ret_n_bind_mounts = 0;
2978 *ret_empty_directories = NULL;
2979 return 0;
2980 }
2981
2982 bind_mounts = new(BindMount, n);
2983 if (!bind_mounts)
2984 return -ENOMEM;
2985
2986 for (size_t i = 0; i < context->n_bind_mounts; i++) {
2987 BindMount *item = context->bind_mounts + i;
2988 char *s, *d;
2989
2990 s = strdup(item->source);
2991 if (!s) {
2992 r = -ENOMEM;
2993 goto finish;
2994 }
2995
2996 d = strdup(item->destination);
2997 if (!d) {
2998 free(s);
2999 r = -ENOMEM;
3000 goto finish;
3001 }
3002
3003 bind_mounts[h++] = (BindMount) {
3004 .source = s,
3005 .destination = d,
3006 .read_only = item->read_only,
3007 .recursive = item->recursive,
3008 .ignore_enoent = item->ignore_enoent,
3009 };
3010 }
3011
3012 for (ExecDirectoryType t = 0; t < _EXEC_DIRECTORY_TYPE_MAX; t++) {
3013 char **suffix;
3014
3015 if (!params->prefix[t])
3016 continue;
3017
3018 if (strv_isempty(context->directories[t].paths))
3019 continue;
3020
3021 if (exec_directory_is_private(context, t) &&
3022 !exec_context_with_rootfs(context)) {
3023 char *private_root;
3024
3025 /* So this is for a dynamic user, and we need to make sure the process can access its own
3026 * directory. For that we overmount the usually inaccessible "private" subdirectory with a
3027 * tmpfs that makes it accessible and is empty except for the submounts we do this for. */
3028
3029 private_root = path_join(params->prefix[t], "private");
3030 if (!private_root) {
3031 r = -ENOMEM;
3032 goto finish;
3033 }
3034
3035 r = strv_consume(&empty_directories, private_root);
3036 if (r < 0)
3037 goto finish;
3038 }
3039
3040 STRV_FOREACH(suffix, context->directories[t].paths) {
3041 char *s, *d;
3042
3043 if (exec_directory_is_private(context, t))
3044 s = path_join(params->prefix[t], "private", *suffix);
3045 else
3046 s = path_join(params->prefix[t], *suffix);
3047 if (!s) {
3048 r = -ENOMEM;
3049 goto finish;
3050 }
3051
3052 if (exec_directory_is_private(context, t) &&
3053 exec_context_with_rootfs(context))
3054 /* When RootDirectory= or RootImage= are set, then the symbolic link to the private
3055 * directory is not created on the root directory. So, let's bind-mount the directory
3056 * on the 'non-private' place. */
3057 d = path_join(params->prefix[t], *suffix);
3058 else
3059 d = strdup(s);
3060 if (!d) {
3061 free(s);
3062 r = -ENOMEM;
3063 goto finish;
3064 }
3065
3066 bind_mounts[h++] = (BindMount) {
3067 .source = s,
3068 .destination = d,
3069 .read_only = false,
3070 .nosuid = context->dynamic_user, /* don't allow suid/sgid when DynamicUser= is on */
3071 .recursive = true,
3072 .ignore_enoent = false,
3073 };
3074 }
3075 }
3076
3077 assert(h == n);
3078
3079 *ret_bind_mounts = bind_mounts;
3080 *ret_n_bind_mounts = n;
3081 *ret_empty_directories = TAKE_PTR(empty_directories);
3082
3083 return (int) n;
3084
3085 finish:
3086 bind_mount_free_many(bind_mounts, h);
3087 return r;
3088 }
3089
3090 static bool insist_on_sandboxing(
3091 const ExecContext *context,
3092 const char *root_dir,
3093 const char *root_image,
3094 const BindMount *bind_mounts,
3095 size_t n_bind_mounts) {
3096
3097 assert(context);
3098 assert(n_bind_mounts == 0 || bind_mounts);
3099
3100 /* Checks whether we need to insist on fs namespacing. i.e. whether we have settings configured that
3101 * would alter the view on the file system beyond making things read-only or invisible, i.e. would
3102 * rearrange stuff in a way we cannot ignore gracefully. */
3103
3104 if (context->n_temporary_filesystems > 0)
3105 return true;
3106
3107 if (root_dir || root_image)
3108 return true;
3109
3110 if (context->n_mount_images > 0)
3111 return true;
3112
3113 if (context->dynamic_user)
3114 return true;
3115
3116 /* If there are any bind mounts set that don't map back onto themselves, fs namespacing becomes
3117 * essential. */
3118 for (size_t i = 0; i < n_bind_mounts; i++)
3119 if (!path_equal(bind_mounts[i].source, bind_mounts[i].destination))
3120 return true;
3121
3122 if (context->log_namespace)
3123 return true;
3124
3125 return false;
3126 }
3127
3128 static int apply_mount_namespace(
3129 const Unit *u,
3130 ExecCommandFlags command_flags,
3131 const ExecContext *context,
3132 const ExecParameters *params,
3133 const ExecRuntime *runtime,
3134 char **error_path) {
3135
3136 _cleanup_strv_free_ char **empty_directories = NULL;
3137 const char *tmp_dir = NULL, *var_tmp_dir = NULL;
3138 const char *root_dir = NULL, *root_image = NULL;
3139 _cleanup_free_ char *creds_path = NULL, *incoming_dir = NULL, *propagate_dir = NULL;
3140 NamespaceInfo ns_info;
3141 bool needs_sandboxing;
3142 BindMount *bind_mounts = NULL;
3143 size_t n_bind_mounts = 0;
3144 int r;
3145
3146 assert(context);
3147
3148 if (params->flags & EXEC_APPLY_CHROOT) {
3149 root_image = context->root_image;
3150
3151 if (!root_image)
3152 root_dir = context->root_directory;
3153 }
3154
3155 r = compile_bind_mounts(context, params, &bind_mounts, &n_bind_mounts, &empty_directories);
3156 if (r < 0)
3157 return r;
3158
3159 needs_sandboxing = (params->flags & EXEC_APPLY_SANDBOXING) && !(command_flags & EXEC_COMMAND_FULLY_PRIVILEGED);
3160 if (needs_sandboxing) {
3161 /* The runtime struct only contains the parent of the private /tmp,
3162 * which is non-accessible to world users. Inside of it there's a /tmp
3163 * that is sticky, and that's the one we want to use here.
3164 * This does not apply when we are using /run/systemd/empty as fallback. */
3165
3166 if (context->private_tmp && runtime) {
3167 if (streq_ptr(runtime->tmp_dir, RUN_SYSTEMD_EMPTY))
3168 tmp_dir = runtime->tmp_dir;
3169 else if (runtime->tmp_dir)
3170 tmp_dir = strjoina(runtime->tmp_dir, "/tmp");
3171
3172 if (streq_ptr(runtime->var_tmp_dir, RUN_SYSTEMD_EMPTY))
3173 var_tmp_dir = runtime->var_tmp_dir;
3174 else if (runtime->var_tmp_dir)
3175 var_tmp_dir = strjoina(runtime->var_tmp_dir, "/tmp");
3176 }
3177
3178 ns_info = (NamespaceInfo) {
3179 .ignore_protect_paths = false,
3180 .private_dev = context->private_devices,
3181 .protect_control_groups = context->protect_control_groups,
3182 .protect_kernel_tunables = context->protect_kernel_tunables,
3183 .protect_kernel_modules = context->protect_kernel_modules,
3184 .protect_kernel_logs = context->protect_kernel_logs,
3185 .protect_hostname = context->protect_hostname,
3186 .mount_apivfs = exec_context_get_effective_mount_apivfs(context),
3187 .private_mounts = context->private_mounts,
3188 .protect_home = context->protect_home,
3189 .protect_system = context->protect_system,
3190 .protect_proc = context->protect_proc,
3191 .proc_subset = context->proc_subset,
3192 .private_ipc = context->private_ipc || context->ipc_namespace_path,
3193 };
3194 } else if (!context->dynamic_user && root_dir)
3195 /*
3196 * If DynamicUser=no and RootDirectory= is set then lets pass a relaxed
3197 * sandbox info, otherwise enforce it, don't ignore protected paths and
3198 * fail if we are enable to apply the sandbox inside the mount namespace.
3199 */
3200 ns_info = (NamespaceInfo) {
3201 .ignore_protect_paths = true,
3202 };
3203 else
3204 ns_info = (NamespaceInfo) {};
3205
3206 if (context->mount_flags == MS_SHARED)
3207 log_unit_debug(u, "shared mount propagation hidden by other fs namespacing unit settings: ignoring");
3208
3209 if (exec_context_has_credentials(context) &&
3210 params->prefix[EXEC_DIRECTORY_RUNTIME] &&
3211 FLAGS_SET(params->flags, EXEC_WRITE_CREDENTIALS)) {
3212 creds_path = path_join(params->prefix[EXEC_DIRECTORY_RUNTIME], "credentials", u->id);
3213 if (!creds_path) {
3214 r = -ENOMEM;
3215 goto finalize;
3216 }
3217 }
3218
3219 if (MANAGER_IS_SYSTEM(u->manager)) {
3220 propagate_dir = path_join("/run/systemd/propagate/", u->id);
3221 if (!propagate_dir) {
3222 r = -ENOMEM;
3223 goto finalize;
3224 }
3225
3226 incoming_dir = strdup("/run/systemd/incoming");
3227 if (!incoming_dir) {
3228 r = -ENOMEM;
3229 goto finalize;
3230 }
3231 }
3232
3233 r = setup_namespace(root_dir, root_image, context->root_image_options,
3234 &ns_info, context->read_write_paths,
3235 needs_sandboxing ? context->read_only_paths : NULL,
3236 needs_sandboxing ? context->inaccessible_paths : NULL,
3237 needs_sandboxing ? context->exec_paths : NULL,
3238 needs_sandboxing ? context->no_exec_paths : NULL,
3239 empty_directories,
3240 bind_mounts,
3241 n_bind_mounts,
3242 context->temporary_filesystems,
3243 context->n_temporary_filesystems,
3244 context->mount_images,
3245 context->n_mount_images,
3246 tmp_dir,
3247 var_tmp_dir,
3248 creds_path,
3249 context->log_namespace,
3250 context->mount_flags,
3251 context->root_hash, context->root_hash_size, context->root_hash_path,
3252 context->root_hash_sig, context->root_hash_sig_size, context->root_hash_sig_path,
3253 context->root_verity,
3254 context->extension_images,
3255 context->n_extension_images,
3256 propagate_dir,
3257 incoming_dir,
3258 root_dir || root_image ? params->notify_socket : NULL,
3259 error_path);
3260
3261 /* If we couldn't set up the namespace this is probably due to a missing capability. setup_namespace() reports
3262 * that with a special, recognizable error ENOANO. In this case, silently proceed, but only if exclusively
3263 * sandboxing options were used, i.e. nothing such as RootDirectory= or BindMount= that would result in a
3264 * completely different execution environment. */
3265 if (r == -ENOANO) {
3266 if (insist_on_sandboxing(
3267 context,
3268 root_dir, root_image,
3269 bind_mounts,
3270 n_bind_mounts)) {
3271 log_unit_debug(u, "Failed to set up namespace, and refusing to continue since the selected namespacing options alter mount environment non-trivially.\n"
3272 "Bind mounts: %zu, temporary filesystems: %zu, root directory: %s, root image: %s, dynamic user: %s",
3273 n_bind_mounts, context->n_temporary_filesystems, yes_no(root_dir), yes_no(root_image), yes_no(context->dynamic_user));
3274
3275 r = -EOPNOTSUPP;
3276 } else {
3277 log_unit_debug(u, "Failed to set up namespace, assuming containerized execution and ignoring.");
3278 r = 0;
3279 }
3280 }
3281
3282 finalize:
3283 bind_mount_free_many(bind_mounts, n_bind_mounts);
3284 return r;
3285 }
3286
3287 static int apply_working_directory(
3288 const ExecContext *context,
3289 const ExecParameters *params,
3290 const char *home,
3291 int *exit_status) {
3292
3293 const char *d, *wd;
3294
3295 assert(context);
3296 assert(exit_status);
3297
3298 if (context->working_directory_home) {
3299
3300 if (!home) {
3301 *exit_status = EXIT_CHDIR;
3302 return -ENXIO;
3303 }
3304
3305 wd = home;
3306
3307 } else
3308 wd = empty_to_root(context->working_directory);
3309
3310 if (params->flags & EXEC_APPLY_CHROOT)
3311 d = wd;
3312 else
3313 d = prefix_roota(context->root_directory, wd);
3314
3315 if (chdir(d) < 0 && !context->working_directory_missing_ok) {
3316 *exit_status = EXIT_CHDIR;
3317 return -errno;
3318 }
3319
3320 return 0;
3321 }
3322
3323 static int apply_root_directory(
3324 const ExecContext *context,
3325 const ExecParameters *params,
3326 const bool needs_mount_ns,
3327 int *exit_status) {
3328
3329 assert(context);
3330 assert(exit_status);
3331
3332 if (params->flags & EXEC_APPLY_CHROOT)
3333 if (!needs_mount_ns && context->root_directory)
3334 if (chroot(context->root_directory) < 0) {
3335 *exit_status = EXIT_CHROOT;
3336 return -errno;
3337 }
3338
3339 return 0;
3340 }
3341
3342 static int setup_keyring(
3343 const Unit *u,
3344 const ExecContext *context,
3345 const ExecParameters *p,
3346 uid_t uid, gid_t gid) {
3347
3348 key_serial_t keyring;
3349 int r = 0;
3350 uid_t saved_uid;
3351 gid_t saved_gid;
3352
3353 assert(u);
3354 assert(context);
3355 assert(p);
3356
3357 /* Let's set up a new per-service "session" kernel keyring for each system service. This has the benefit that
3358 * each service runs with its own keyring shared among all processes of the service, but with no hook-up beyond
3359 * that scope, and in particular no link to the per-UID keyring. If we don't do this the keyring will be
3360 * automatically created on-demand and then linked to the per-UID keyring, by the kernel. The kernel's built-in
3361 * on-demand behaviour is very appropriate for login users, but probably not so much for system services, where
3362 * UIDs are not necessarily specific to a service but reused (at least in the case of UID 0). */
3363
3364 if (context->keyring_mode == EXEC_KEYRING_INHERIT)
3365 return 0;
3366
3367 /* Acquiring a reference to the user keyring is nasty. We briefly change identity in order to get things set up
3368 * properly by the kernel. If we don't do that then we can't create it atomically, and that sucks for parallel
3369 * execution. This mimics what pam_keyinit does, too. Setting up session keyring, to be owned by the right user
3370 * & group is just as nasty as acquiring a reference to the user keyring. */
3371
3372 saved_uid = getuid();
3373 saved_gid = getgid();
3374
3375 if (gid_is_valid(gid) && gid != saved_gid) {
3376 if (setregid(gid, -1) < 0)
3377 return log_unit_error_errno(u, errno, "Failed to change GID for user keyring: %m");
3378 }
3379
3380 if (uid_is_valid(uid) && uid != saved_uid) {
3381 if (setreuid(uid, -1) < 0) {
3382 r = log_unit_error_errno(u, errno, "Failed to change UID for user keyring: %m");
3383 goto out;
3384 }
3385 }
3386
3387 keyring = keyctl(KEYCTL_JOIN_SESSION_KEYRING, 0, 0, 0, 0);
3388 if (keyring == -1) {
3389 if (errno == ENOSYS)
3390 log_unit_debug_errno(u, errno, "Kernel keyring not supported, ignoring.");
3391 else if (ERRNO_IS_PRIVILEGE(errno))
3392 log_unit_debug_errno(u, errno, "Kernel keyring access prohibited, ignoring.");
3393 else if (errno == EDQUOT)
3394 log_unit_debug_errno(u, errno, "Out of kernel keyrings to allocate, ignoring.");
3395 else
3396 r = log_unit_error_errno(u, errno, "Setting up kernel keyring failed: %m");
3397
3398 goto out;
3399 }
3400
3401 /* When requested link the user keyring into the session keyring. */
3402 if (context->keyring_mode == EXEC_KEYRING_SHARED) {
3403
3404 if (keyctl(KEYCTL_LINK,
3405 KEY_SPEC_USER_KEYRING,
3406 KEY_SPEC_SESSION_KEYRING, 0, 0) < 0) {
3407 r = log_unit_error_errno(u, errno, "Failed to link user keyring into session keyring: %m");
3408 goto out;
3409 }
3410 }
3411
3412 /* Restore uid/gid back */
3413 if (uid_is_valid(uid) && uid != saved_uid) {
3414 if (setreuid(saved_uid, -1) < 0) {
3415 r = log_unit_error_errno(u, errno, "Failed to change UID back for user keyring: %m");
3416 goto out;
3417 }
3418 }
3419
3420 if (gid_is_valid(gid) && gid != saved_gid) {
3421 if (setregid(saved_gid, -1) < 0)
3422 return log_unit_error_errno(u, errno, "Failed to change GID back for user keyring: %m");
3423 }
3424
3425 /* Populate they keyring with the invocation ID by default, as original saved_uid. */
3426 if (!sd_id128_is_null(u->invocation_id)) {
3427 key_serial_t key;
3428
3429 key = add_key("user", "invocation_id", &u->invocation_id, sizeof(u->invocation_id), KEY_SPEC_SESSION_KEYRING);
3430 if (key == -1)
3431 log_unit_debug_errno(u, errno, "Failed to add invocation ID to keyring, ignoring: %m");
3432 else {
3433 if (keyctl(KEYCTL_SETPERM, key,
3434 KEY_POS_VIEW|KEY_POS_READ|KEY_POS_SEARCH|
3435 KEY_USR_VIEW|KEY_USR_READ|KEY_USR_SEARCH, 0, 0) < 0)
3436 r = log_unit_error_errno(u, errno, "Failed to restrict invocation ID permission: %m");
3437 }
3438 }
3439
3440 out:
3441 /* Revert back uid & gid for the last time, and exit */
3442 /* no extra logging, as only the first already reported error matters */
3443 if (getuid() != saved_uid)
3444 (void) setreuid(saved_uid, -1);
3445
3446 if (getgid() != saved_gid)
3447 (void) setregid(saved_gid, -1);
3448
3449 return r;
3450 }
3451
3452 static void append_socket_pair(int *array, size_t *n, const int pair[static 2]) {
3453 assert(array);
3454 assert(n);
3455 assert(pair);
3456
3457 if (pair[0] >= 0)
3458 array[(*n)++] = pair[0];
3459 if (pair[1] >= 0)
3460 array[(*n)++] = pair[1];
3461 }
3462
3463 static int close_remaining_fds(
3464 const ExecParameters *params,
3465 const ExecRuntime *runtime,
3466 const DynamicCreds *dcreds,
3467 int user_lookup_fd,
3468 int socket_fd,
3469 const int *fds, size_t n_fds) {
3470
3471 size_t n_dont_close = 0;
3472 int dont_close[n_fds + 12];
3473
3474 assert(params);
3475
3476 if (params->stdin_fd >= 0)
3477 dont_close[n_dont_close++] = params->stdin_fd;
3478 if (params->stdout_fd >= 0)
3479 dont_close[n_dont_close++] = params->stdout_fd;
3480 if (params->stderr_fd >= 0)
3481 dont_close[n_dont_close++] = params->stderr_fd;
3482
3483 if (socket_fd >= 0)
3484 dont_close[n_dont_close++] = socket_fd;
3485 if (n_fds > 0) {
3486 memcpy(dont_close + n_dont_close, fds, sizeof(int) * n_fds);
3487 n_dont_close += n_fds;
3488 }
3489
3490 if (runtime) {
3491 append_socket_pair(dont_close, &n_dont_close, runtime->netns_storage_socket);
3492 append_socket_pair(dont_close, &n_dont_close, runtime->ipcns_storage_socket);
3493 }
3494
3495 if (dcreds) {
3496 if (dcreds->user)
3497 append_socket_pair(dont_close, &n_dont_close, dcreds->user->storage_socket);
3498 if (dcreds->group)
3499 append_socket_pair(dont_close, &n_dont_close, dcreds->group->storage_socket);
3500 }
3501
3502 if (user_lookup_fd >= 0)
3503 dont_close[n_dont_close++] = user_lookup_fd;
3504
3505 return close_all_fds(dont_close, n_dont_close);
3506 }
3507
3508 static int send_user_lookup(
3509 Unit *unit,
3510 int user_lookup_fd,
3511 uid_t uid,
3512 gid_t gid) {
3513
3514 assert(unit);
3515
3516 /* Send the resolved UID/GID to PID 1 after we learnt it. We send a single datagram, containing the UID/GID
3517 * data as well as the unit name. Note that we suppress sending this if no user/group to resolve was
3518 * specified. */
3519
3520 if (user_lookup_fd < 0)
3521 return 0;
3522
3523 if (!uid_is_valid(uid) && !gid_is_valid(gid))
3524 return 0;
3525
3526 if (writev(user_lookup_fd,
3527 (struct iovec[]) {
3528 IOVEC_INIT(&uid, sizeof(uid)),
3529 IOVEC_INIT(&gid, sizeof(gid)),
3530 IOVEC_INIT_STRING(unit->id) }, 3) < 0)
3531 return -errno;
3532
3533 return 0;
3534 }
3535
3536 static int acquire_home(const ExecContext *c, uid_t uid, const char** home, char **buf) {
3537 int r;
3538
3539 assert(c);
3540 assert(home);
3541 assert(buf);
3542
3543 /* If WorkingDirectory=~ is set, try to acquire a usable home directory. */
3544
3545 if (*home)
3546 return 0;
3547
3548 if (!c->working_directory_home)
3549 return 0;
3550
3551 r = get_home_dir(buf);
3552 if (r < 0)
3553 return r;
3554
3555 *home = *buf;
3556 return 1;
3557 }
3558
3559 static int compile_suggested_paths(const ExecContext *c, const ExecParameters *p, char ***ret) {
3560 _cleanup_strv_free_ char ** list = NULL;
3561 int r;
3562
3563 assert(c);
3564 assert(p);
3565 assert(ret);
3566
3567 assert(c->dynamic_user);
3568
3569 /* Compile a list of paths that it might make sense to read the owning UID from to use as initial candidate for
3570 * dynamic UID allocation, in order to save us from doing costly recursive chown()s of the special
3571 * directories. */
3572
3573 for (ExecDirectoryType t = 0; t < _EXEC_DIRECTORY_TYPE_MAX; t++) {
3574 char **i;
3575
3576 if (t == EXEC_DIRECTORY_CONFIGURATION)
3577 continue;
3578
3579 if (!p->prefix[t])
3580 continue;
3581
3582 STRV_FOREACH(i, c->directories[t].paths) {
3583 char *e;
3584
3585 if (exec_directory_is_private(c, t))
3586 e = path_join(p->prefix[t], "private", *i);
3587 else
3588 e = path_join(p->prefix[t], *i);
3589 if (!e)
3590 return -ENOMEM;
3591
3592 r = strv_consume(&list, e);
3593 if (r < 0)
3594 return r;
3595 }
3596 }
3597
3598 *ret = TAKE_PTR(list);
3599
3600 return 0;
3601 }
3602
3603 static char *exec_command_line(char **argv);
3604
3605 static int exec_parameters_get_cgroup_path(const ExecParameters *params, char **ret) {
3606 bool using_subcgroup;
3607 char *p;
3608
3609 assert(params);
3610 assert(ret);
3611
3612 if (!params->cgroup_path)
3613 return -EINVAL;
3614
3615 /* If we are called for a unit where cgroup delegation is on, and the payload created its own populated
3616 * subcgroup (which we expect it to do, after all it asked for delegation), then we cannot place the control
3617 * processes started after the main unit's process in the unit's main cgroup because it is now an inner one,
3618 * and inner cgroups may not contain processes. Hence, if delegation is on, and this is a control process,
3619 * let's use ".control" as subcgroup instead. Note that we do so only for ExecStartPost=, ExecReload=,
3620 * ExecStop=, ExecStopPost=, i.e. for the commands where the main process is already forked. For ExecStartPre=
3621 * this is not necessary, the cgroup is still empty. We distinguish these cases with the EXEC_CONTROL_CGROUP
3622 * flag, which is only passed for the former statements, not for the latter. */
3623
3624 using_subcgroup = FLAGS_SET(params->flags, EXEC_CONTROL_CGROUP|EXEC_CGROUP_DELEGATE|EXEC_IS_CONTROL);
3625 if (using_subcgroup)
3626 p = path_join(params->cgroup_path, ".control");
3627 else
3628 p = strdup(params->cgroup_path);
3629 if (!p)
3630 return -ENOMEM;
3631
3632 *ret = p;
3633 return using_subcgroup;
3634 }
3635
3636 static int exec_context_cpu_affinity_from_numa(const ExecContext *c, CPUSet *ret) {
3637 _cleanup_(cpu_set_reset) CPUSet s = {};
3638 int r;
3639
3640 assert(c);
3641 assert(ret);
3642
3643 if (!c->numa_policy.nodes.set) {
3644 log_debug("Can't derive CPU affinity mask from NUMA mask because NUMA mask is not set, ignoring");
3645 return 0;
3646 }
3647
3648 r = numa_to_cpu_set(&c->numa_policy, &s);
3649 if (r < 0)
3650 return r;
3651
3652 cpu_set_reset(ret);
3653
3654 return cpu_set_add_all(ret, &s);
3655 }
3656
3657 bool exec_context_get_cpu_affinity_from_numa(const ExecContext *c) {
3658 assert(c);
3659
3660 return c->cpu_affinity_from_numa;
3661 }
3662
3663 static int add_shifted_fd(int *fds, size_t fds_size, size_t *n_fds, int fd, int *ret_fd) {
3664 int r;
3665
3666 assert(fds);
3667 assert(n_fds);
3668 assert(*n_fds < fds_size);
3669 assert(ret_fd);
3670
3671 if (fd < 0) {
3672 *ret_fd = -1;
3673 return 0;
3674 }
3675
3676 if (fd < 3 + (int) *n_fds) {
3677 /* Let's move the fd up, so that it's outside of the fd range we will use to store
3678 * the fds we pass to the process (or which are closed only during execve). */
3679
3680 r = fcntl(fd, F_DUPFD_CLOEXEC, 3 + (int) *n_fds);
3681 if (r < 0)
3682 return -errno;
3683
3684 CLOSE_AND_REPLACE(fd, r);
3685 }
3686
3687 *ret_fd = fds[*n_fds] = fd;
3688 (*n_fds) ++;
3689 return 1;
3690 }
3691
3692 static int exec_child(
3693 Unit *unit,
3694 const ExecCommand *command,
3695 const ExecContext *context,
3696 const ExecParameters *params,
3697 ExecRuntime *runtime,
3698 DynamicCreds *dcreds,
3699 int socket_fd,
3700 const int named_iofds[static 3],
3701 int *fds,
3702 size_t n_socket_fds,
3703 size_t n_storage_fds,
3704 char **files_env,
3705 int user_lookup_fd,
3706 int *exit_status) {
3707
3708 _cleanup_strv_free_ char **our_env = NULL, **pass_env = NULL, **accum_env = NULL, **replaced_argv = NULL;
3709 int r, ngids = 0, exec_fd;
3710 _cleanup_free_ gid_t *supplementary_gids = NULL;
3711 const char *username = NULL, *groupname = NULL;
3712 _cleanup_free_ char *home_buffer = NULL;
3713 const char *home = NULL, *shell = NULL;
3714 char **final_argv = NULL;
3715 dev_t journal_stream_dev = 0;
3716 ino_t journal_stream_ino = 0;
3717 bool userns_set_up = false;
3718 bool needs_sandboxing, /* Do we need to set up full sandboxing? (i.e. all namespacing, all MAC stuff, caps, yadda yadda */
3719 needs_setuid, /* Do we need to do the actual setresuid()/setresgid() calls? */
3720 needs_mount_namespace, /* Do we need to set up a mount namespace for this kernel? */
3721 needs_ambient_hack; /* Do we need to apply the ambient capabilities hack? */
3722 #if HAVE_SELINUX
3723 _cleanup_free_ char *mac_selinux_context_net = NULL;
3724 bool use_selinux = false;
3725 #endif
3726 #if ENABLE_SMACK
3727 bool use_smack = false;
3728 #endif
3729 #if HAVE_APPARMOR
3730 bool use_apparmor = false;
3731 #endif
3732 uid_t saved_uid = getuid();
3733 gid_t saved_gid = getgid();
3734 uid_t uid = UID_INVALID;
3735 gid_t gid = GID_INVALID;
3736 size_t n_fds = n_socket_fds + n_storage_fds, /* fds to pass to the child */
3737 n_keep_fds; /* total number of fds not to close */
3738 int secure_bits;
3739 _cleanup_free_ gid_t *gids_after_pam = NULL;
3740 int ngids_after_pam = 0;
3741
3742 assert(unit);
3743 assert(command);
3744 assert(context);
3745 assert(params);
3746 assert(exit_status);
3747
3748 rename_process_from_path(command->path);
3749
3750 /* We reset exactly these signals, since they are the only ones we set to SIG_IGN in the main
3751 * daemon. All others we leave untouched because we set them to SIG_DFL or a valid handler initially,
3752 * both of which will be demoted to SIG_DFL. */
3753 (void) default_signals(SIGNALS_CRASH_HANDLER,
3754 SIGNALS_IGNORE);
3755
3756 if (context->ignore_sigpipe)
3757 (void) ignore_signals(SIGPIPE);
3758
3759 r = reset_signal_mask();
3760 if (r < 0) {
3761 *exit_status = EXIT_SIGNAL_MASK;
3762 return log_unit_error_errno(unit, r, "Failed to set process signal mask: %m");
3763 }
3764
3765 if (params->idle_pipe)
3766 do_idle_pipe_dance(params->idle_pipe);
3767
3768 /* Close fds we don't need very early to make sure we don't block init reexecution because it cannot bind its
3769 * sockets. Among the fds we close are the logging fds, and we want to keep them closed, so that we don't have
3770 * any fds open we don't really want open during the transition. In order to make logging work, we switch the
3771 * log subsystem into open_when_needed mode, so that it reopens the logs on every single log call. */
3772
3773 log_forget_fds();
3774 log_set_open_when_needed(true);
3775
3776 /* In case anything used libc syslog(), close this here, too */
3777 closelog();
3778
3779 int keep_fds[n_fds + 2];
3780 memcpy_safe(keep_fds, fds, n_fds * sizeof(int));
3781 n_keep_fds = n_fds;
3782
3783 r = add_shifted_fd(keep_fds, ELEMENTSOF(keep_fds), &n_keep_fds, params->exec_fd, &exec_fd);
3784 if (r < 0) {
3785 *exit_status = EXIT_FDS;
3786 return log_unit_error_errno(unit, r, "Failed to shift fd and set FD_CLOEXEC: %m");
3787 }
3788
3789 r = close_remaining_fds(params, runtime, dcreds, user_lookup_fd, socket_fd, keep_fds, n_keep_fds);
3790 if (r < 0) {
3791 *exit_status = EXIT_FDS;
3792 return log_unit_error_errno(unit, r, "Failed to close unwanted file descriptors: %m");
3793 }
3794
3795 if (!context->same_pgrp &&
3796 setsid() < 0) {
3797 *exit_status = EXIT_SETSID;
3798 return log_unit_error_errno(unit, errno, "Failed to create new process session: %m");
3799 }
3800
3801 exec_context_tty_reset(context, params);
3802
3803 if (unit_shall_confirm_spawn(unit)) {
3804 const char *vc = params->confirm_spawn;
3805 _cleanup_free_ char *cmdline = NULL;
3806
3807 cmdline = exec_command_line(command->argv);
3808 if (!cmdline) {
3809 *exit_status = EXIT_MEMORY;
3810 return log_oom();
3811 }
3812
3813 r = ask_for_confirmation(vc, unit, cmdline);
3814 if (r != CONFIRM_EXECUTE) {
3815 if (r == CONFIRM_PRETEND_SUCCESS) {
3816 *exit_status = EXIT_SUCCESS;
3817 return 0;
3818 }
3819 *exit_status = EXIT_CONFIRM;
3820 return log_unit_error_errno(unit, SYNTHETIC_ERRNO(ECANCELED),
3821 "Execution cancelled by the user");
3822 }
3823 }
3824
3825 /* We are about to invoke NSS and PAM modules. Let's tell them what we are doing here, maybe they care. This is
3826 * used by nss-resolve to disable itself when we are about to start systemd-resolved, to avoid deadlocks. Note
3827 * that these env vars do not survive the execve(), which means they really only apply to the PAM and NSS
3828 * invocations themselves. Also note that while we'll only invoke NSS modules involved in user management they
3829 * might internally call into other NSS modules that are involved in hostname resolution, we never know. */
3830 if (setenv("SYSTEMD_ACTIVATION_UNIT", unit->id, true) != 0 ||
3831 setenv("SYSTEMD_ACTIVATION_SCOPE", MANAGER_IS_SYSTEM(unit->manager) ? "system" : "user", true) != 0) {
3832 *exit_status = EXIT_MEMORY;
3833 return log_unit_error_errno(unit, errno, "Failed to update environment: %m");
3834 }
3835
3836 if (context->dynamic_user && dcreds) {
3837 _cleanup_strv_free_ char **suggested_paths = NULL;
3838
3839 /* On top of that, make sure we bypass our own NSS module nss-systemd comprehensively for any NSS
3840 * checks, if DynamicUser=1 is used, as we shouldn't create a feedback loop with ourselves here. */
3841 if (putenv((char*) "SYSTEMD_NSS_DYNAMIC_BYPASS=1") != 0) {
3842 *exit_status = EXIT_USER;
3843 return log_unit_error_errno(unit, errno, "Failed to update environment: %m");
3844 }
3845
3846 r = compile_suggested_paths(context, params, &suggested_paths);
3847 if (r < 0) {
3848 *exit_status = EXIT_MEMORY;
3849 return log_oom();
3850 }
3851
3852 r = dynamic_creds_realize(dcreds, suggested_paths, &uid, &gid);
3853 if (r < 0) {
3854 *exit_status = EXIT_USER;
3855 if (r == -EILSEQ)
3856 return log_unit_error_errno(unit, SYNTHETIC_ERRNO(EOPNOTSUPP),
3857 "Failed to update dynamic user credentials: User or group with specified name already exists.");
3858 return log_unit_error_errno(unit, r, "Failed to update dynamic user credentials: %m");
3859 }
3860
3861 if (!uid_is_valid(uid)) {
3862 *exit_status = EXIT_USER;
3863 return log_unit_error_errno(unit, SYNTHETIC_ERRNO(ESRCH), "UID validation failed for \""UID_FMT"\"", uid);
3864 }
3865
3866 if (!gid_is_valid(gid)) {
3867 *exit_status = EXIT_USER;
3868 return log_unit_error_errno(unit, SYNTHETIC_ERRNO(ESRCH), "GID validation failed for \""GID_FMT"\"", gid);
3869 }
3870
3871 if (dcreds->user)
3872 username = dcreds->user->name;
3873
3874 } else {
3875 r = get_fixed_user(context, &username, &uid, &gid, &home, &shell);
3876 if (r < 0) {
3877 *exit_status = EXIT_USER;
3878 return log_unit_error_errno(unit, r, "Failed to determine user credentials: %m");
3879 }
3880
3881 r = get_fixed_group(context, &groupname, &gid);
3882 if (r < 0) {
3883 *exit_status = EXIT_GROUP;
3884 return log_unit_error_errno(unit, r, "Failed to determine group credentials: %m");
3885 }
3886 }
3887
3888 /* Initialize user supplementary groups and get SupplementaryGroups= ones */
3889 r = get_supplementary_groups(context, username, groupname, gid,
3890 &supplementary_gids, &ngids);
3891 if (r < 0) {
3892 *exit_status = EXIT_GROUP;
3893 return log_unit_error_errno(unit, r, "Failed to determine supplementary groups: %m");
3894 }
3895
3896 r = send_user_lookup(unit, user_lookup_fd, uid, gid);
3897 if (r < 0) {
3898 *exit_status = EXIT_USER;
3899 return log_unit_error_errno(unit, r, "Failed to send user credentials to PID1: %m");
3900 }
3901
3902 user_lookup_fd = safe_close(user_lookup_fd);
3903
3904 r = acquire_home(context, uid, &home, &home_buffer);
3905 if (r < 0) {
3906 *exit_status = EXIT_CHDIR;
3907 return log_unit_error_errno(unit, r, "Failed to determine $HOME for user: %m");
3908 }
3909
3910 /* If a socket is connected to STDIN/STDOUT/STDERR, we
3911 * must sure to drop O_NONBLOCK */
3912 if (socket_fd >= 0)
3913 (void) fd_nonblock(socket_fd, false);
3914
3915 /* Journald will try to look-up our cgroup in order to populate _SYSTEMD_CGROUP and _SYSTEMD_UNIT fields.
3916 * Hence we need to migrate to the target cgroup from init.scope before connecting to journald */
3917 if (params->cgroup_path) {
3918 _cleanup_free_ char *p = NULL;
3919
3920 r = exec_parameters_get_cgroup_path(params, &p);
3921 if (r < 0) {
3922 *exit_status = EXIT_CGROUP;
3923 return log_unit_error_errno(unit, r, "Failed to acquire cgroup path: %m");
3924 }
3925
3926 r = cg_attach_everywhere(params->cgroup_supported, p, 0, NULL, NULL);
3927 if (r < 0) {
3928 *exit_status = EXIT_CGROUP;
3929 return log_unit_error_errno(unit, r, "Failed to attach to cgroup %s: %m", p);
3930 }
3931 }
3932
3933 if (context->network_namespace_path && runtime && runtime->netns_storage_socket[0] >= 0) {
3934 r = open_shareable_ns_path(runtime->netns_storage_socket, context->network_namespace_path, CLONE_NEWNET);
3935 if (r < 0) {
3936 *exit_status = EXIT_NETWORK;
3937 return log_unit_error_errno(unit, r, "Failed to open network namespace path %s: %m", context->network_namespace_path);
3938 }
3939 }
3940
3941 if (context->ipc_namespace_path && runtime && runtime->ipcns_storage_socket[0] >= 0) {
3942 r = open_shareable_ns_path(runtime->ipcns_storage_socket, context->ipc_namespace_path, CLONE_NEWIPC);
3943 if (r < 0) {
3944 *exit_status = EXIT_NAMESPACE;
3945 return log_unit_error_errno(unit, r, "Failed to open IPC namespace path %s: %m", context->ipc_namespace_path);
3946 }
3947 }
3948
3949 r = setup_input(context, params, socket_fd, named_iofds);
3950 if (r < 0) {
3951 *exit_status = EXIT_STDIN;
3952 return log_unit_error_errno(unit, r, "Failed to set up standard input: %m");
3953 }
3954
3955 r = setup_output(unit, context, params, STDOUT_FILENO, socket_fd, named_iofds, basename(command->path), uid, gid, &journal_stream_dev, &journal_stream_ino);
3956 if (r < 0) {
3957 *exit_status = EXIT_STDOUT;
3958 return log_unit_error_errno(unit, r, "Failed to set up standard output: %m");
3959 }
3960
3961 r = setup_output(unit, context, params, STDERR_FILENO, socket_fd, named_iofds, basename(command->path), uid, gid, &journal_stream_dev, &journal_stream_ino);
3962 if (r < 0) {
3963 *exit_status = EXIT_STDERR;
3964 return log_unit_error_errno(unit, r, "Failed to set up standard error output: %m");
3965 }
3966
3967 if (context->oom_score_adjust_set) {
3968 /* When we can't make this change due to EPERM, then let's silently skip over it. User namespaces
3969 * prohibit write access to this file, and we shouldn't trip up over that. */
3970 r = set_oom_score_adjust(context->oom_score_adjust);
3971 if (ERRNO_IS_PRIVILEGE(r))
3972 log_unit_debug_errno(unit, r, "Failed to adjust OOM setting, assuming containerized execution, ignoring: %m");
3973 else if (r < 0) {
3974 *exit_status = EXIT_OOM_ADJUST;
3975 return log_unit_error_errno(unit, r, "Failed to adjust OOM setting: %m");
3976 }
3977 }
3978
3979 if (context->coredump_filter_set) {
3980 r = set_coredump_filter(context->coredump_filter);
3981 if (ERRNO_IS_PRIVILEGE(r))
3982 log_unit_debug_errno(unit, r, "Failed to adjust coredump_filter, ignoring: %m");
3983 else if (r < 0)
3984 return log_unit_error_errno(unit, r, "Failed to adjust coredump_filter: %m");
3985 }
3986
3987 if (context->nice_set) {
3988 r = setpriority_closest(context->nice);
3989 if (r < 0)
3990 return log_unit_error_errno(unit, r, "Failed to set up process scheduling priority (nice level): %m");
3991 }
3992
3993 if (context->cpu_sched_set) {
3994 struct sched_param param = {
3995 .sched_priority = context->cpu_sched_priority,
3996 };
3997
3998 r = sched_setscheduler(0,
3999 context->cpu_sched_policy |
4000 (context->cpu_sched_reset_on_fork ?
4001 SCHED_RESET_ON_FORK : 0),
4002 &param);
4003 if (r < 0) {
4004 *exit_status = EXIT_SETSCHEDULER;
4005 return log_unit_error_errno(unit, errno, "Failed to set up CPU scheduling: %m");
4006 }
4007 }
4008
4009 if (context->cpu_affinity_from_numa || context->cpu_set.set) {
4010 _cleanup_(cpu_set_reset) CPUSet converted_cpu_set = {};
4011 const CPUSet *cpu_set;
4012
4013 if (context->cpu_affinity_from_numa) {
4014 r = exec_context_cpu_affinity_from_numa(context, &converted_cpu_set);
4015 if (r < 0) {
4016 *exit_status = EXIT_CPUAFFINITY;
4017 return log_unit_error_errno(unit, r, "Failed to derive CPU affinity mask from NUMA mask: %m");
4018 }
4019
4020 cpu_set = &converted_cpu_set;
4021 } else
4022 cpu_set = &context->cpu_set;
4023
4024 if (sched_setaffinity(0, cpu_set->allocated, cpu_set->set) < 0) {
4025 *exit_status = EXIT_CPUAFFINITY;
4026 return log_unit_error_errno(unit, errno, "Failed to set up CPU affinity: %m");
4027 }
4028 }
4029
4030 if (mpol_is_valid(numa_policy_get_type(&context->numa_policy))) {
4031 r = apply_numa_policy(&context->numa_policy);
4032 if (r == -EOPNOTSUPP)
4033 log_unit_debug_errno(unit, r, "NUMA support not available, ignoring.");
4034 else if (r < 0) {
4035 *exit_status = EXIT_NUMA_POLICY;
4036 return log_unit_error_errno(unit, r, "Failed to set NUMA memory policy: %m");
4037 }
4038 }
4039
4040 if (context->ioprio_set)
4041 if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
4042 *exit_status = EXIT_IOPRIO;
4043 return log_unit_error_errno(unit, errno, "Failed to set up IO scheduling priority: %m");
4044 }
4045
4046 if (context->timer_slack_nsec != NSEC_INFINITY)
4047 if (prctl(PR_SET_TIMERSLACK, context->timer_slack_nsec) < 0) {
4048 *exit_status = EXIT_TIMERSLACK;
4049 return log_unit_error_errno(unit, errno, "Failed to set up timer slack: %m");
4050 }
4051
4052 if (context->personality != PERSONALITY_INVALID) {
4053 r = safe_personality(context->personality);
4054 if (r < 0) {
4055 *exit_status = EXIT_PERSONALITY;
4056 return log_unit_error_errno(unit, r, "Failed to set up execution domain (personality): %m");
4057 }
4058 }
4059
4060 if (context->utmp_id)
4061 utmp_put_init_process(context->utmp_id, getpid_cached(), getsid(0),
4062 context->tty_path,
4063 context->utmp_mode == EXEC_UTMP_INIT ? INIT_PROCESS :
4064 context->utmp_mode == EXEC_UTMP_LOGIN ? LOGIN_PROCESS :
4065 USER_PROCESS,
4066 username);
4067
4068 if (uid_is_valid(uid)) {
4069 r = chown_terminal(STDIN_FILENO, uid);
4070 if (r < 0) {
4071 *exit_status = EXIT_STDIN;
4072 return log_unit_error_errno(unit, r, "Failed to change ownership of terminal: %m");
4073 }
4074 }
4075
4076 /* If delegation is enabled we'll pass ownership of the cgroup to the user of the new process. On cgroup v1
4077 * this is only about systemd's own hierarchy, i.e. not the controller hierarchies, simply because that's not
4078 * safe. On cgroup v2 there's only one hierarchy anyway, and delegation is safe there, hence in that case only
4079 * touch a single hierarchy too. */
4080 if (params->cgroup_path && context->user && (params->flags & EXEC_CGROUP_DELEGATE)) {
4081 r = cg_set_access(SYSTEMD_CGROUP_CONTROLLER, params->cgroup_path, uid, gid);
4082 if (r < 0) {
4083 *exit_status = EXIT_CGROUP;
4084 return log_unit_error_errno(unit, r, "Failed to adjust control group access: %m");
4085 }
4086 }
4087
4088 for (ExecDirectoryType dt = 0; dt < _EXEC_DIRECTORY_TYPE_MAX; dt++) {
4089 r = setup_exec_directory(context, params, uid, gid, dt, exit_status);
4090 if (r < 0)
4091 return log_unit_error_errno(unit, r, "Failed to set up special execution directory in %s: %m", params->prefix[dt]);
4092 }
4093
4094 if (FLAGS_SET(params->flags, EXEC_WRITE_CREDENTIALS)) {
4095 r = setup_credentials(context, params, unit->id, uid);
4096 if (r < 0) {
4097 *exit_status = EXIT_CREDENTIALS;
4098 return log_unit_error_errno(unit, r, "Failed to set up credentials: %m");
4099 }
4100 }
4101
4102 r = build_environment(
4103 unit,
4104 context,
4105 params,
4106 n_fds,
4107 home,
4108 username,
4109 shell,
4110 journal_stream_dev,
4111 journal_stream_ino,
4112 &our_env);
4113 if (r < 0) {
4114 *exit_status = EXIT_MEMORY;
4115 return log_oom();
4116 }
4117
4118 r = build_pass_environment(context, &pass_env);
4119 if (r < 0) {
4120 *exit_status = EXIT_MEMORY;
4121 return log_oom();
4122 }
4123
4124 accum_env = strv_env_merge(5,
4125 params->environment,
4126 our_env,
4127 pass_env,
4128 context->environment,
4129 files_env);
4130 if (!accum_env) {
4131 *exit_status = EXIT_MEMORY;
4132 return log_oom();
4133 }
4134 accum_env = strv_env_clean(accum_env);
4135
4136 (void) umask(context->umask);
4137
4138 r = setup_keyring(unit, context, params, uid, gid);
4139 if (r < 0) {
4140 *exit_status = EXIT_KEYRING;
4141 return log_unit_error_errno(unit, r, "Failed to set up kernel keyring: %m");
4142 }
4143
4144 /* We need sandboxing if the caller asked us to apply it and the command isn't explicitly excepted from it */
4145 needs_sandboxing = (params->flags & EXEC_APPLY_SANDBOXING) && !(command->flags & EXEC_COMMAND_FULLY_PRIVILEGED);
4146
4147 /* We need the ambient capability hack, if the caller asked us to apply it and the command is marked for it, and the kernel doesn't actually support ambient caps */
4148 needs_ambient_hack = (params->flags & EXEC_APPLY_SANDBOXING) && (command->flags & EXEC_COMMAND_AMBIENT_MAGIC) && !ambient_capabilities_supported();
4149
4150 /* We need setresuid() if the caller asked us to apply sandboxing and the command isn't explicitly excepted from either whole sandboxing or just setresuid() itself, and the ambient hack is not desired */
4151 if (needs_ambient_hack)
4152 needs_setuid = false;
4153 else
4154 needs_setuid = (params->flags & EXEC_APPLY_SANDBOXING) && !(command->flags & (EXEC_COMMAND_FULLY_PRIVILEGED|EXEC_COMMAND_NO_SETUID));
4155
4156 if (needs_sandboxing) {
4157 /* MAC enablement checks need to be done before a new mount ns is created, as they rely on /sys being
4158 * present. The actual MAC context application will happen later, as late as possible, to avoid
4159 * impacting our own code paths. */
4160
4161 #if HAVE_SELINUX
4162 use_selinux = mac_selinux_use();
4163 #endif
4164 #if ENABLE_SMACK
4165 use_smack = mac_smack_use();
4166 #endif
4167 #if HAVE_APPARMOR
4168 use_apparmor = mac_apparmor_use();
4169 #endif
4170 }
4171
4172 if (needs_sandboxing) {
4173 int which_failed;
4174
4175 /* Let's set the resource limits before we call into PAM, so that pam_limits wins over what
4176 * is set here. (See below.) */
4177
4178 r = setrlimit_closest_all((const struct rlimit* const *) context->rlimit, &which_failed);
4179 if (r < 0) {
4180 *exit_status = EXIT_LIMITS;
4181 return log_unit_error_errno(unit, r, "Failed to adjust resource limit RLIMIT_%s: %m", rlimit_to_string(which_failed));
4182 }
4183 }
4184
4185 if (needs_setuid && context->pam_name && username) {
4186 /* Let's call into PAM after we set up our own idea of resource limits to that pam_limits
4187 * wins here. (See above.) */
4188
4189 /* All fds passed in the fds array will be closed in the pam child process. */
4190 r = setup_pam(context->pam_name, username, uid, gid, context->tty_path, &accum_env, fds, n_fds);
4191 if (r < 0) {
4192 *exit_status = EXIT_PAM;
4193 return log_unit_error_errno(unit, r, "Failed to set up PAM session: %m");
4194 }
4195
4196 ngids_after_pam = getgroups_alloc(&gids_after_pam);
4197 if (ngids_after_pam < 0) {
4198 *exit_status = EXIT_MEMORY;
4199 return log_unit_error_errno(unit, ngids_after_pam, "Failed to obtain groups after setting up PAM: %m");
4200 }
4201 }
4202
4203 if (needs_sandboxing && context->private_users && !have_effective_cap(CAP_SYS_ADMIN)) {
4204 /* If we're unprivileged, set up the user namespace first to enable use of the other namespaces.
4205 * Users with CAP_SYS_ADMIN can set up user namespaces last because they will be able to
4206 * set up the all of the other namespaces (i.e. network, mount, UTS) without a user namespace. */
4207
4208 userns_set_up = true;
4209 r = setup_private_users(saved_uid, saved_gid, uid, gid);
4210 if (r < 0) {
4211 *exit_status = EXIT_USER;
4212 return log_unit_error_errno(unit, r, "Failed to set up user namespacing for unprivileged user: %m");
4213 }
4214 }
4215
4216 if ((context->private_network || context->network_namespace_path) && runtime && runtime->netns_storage_socket[0] >= 0) {
4217
4218 if (ns_type_supported(NAMESPACE_NET)) {
4219 r = setup_shareable_ns(runtime->netns_storage_socket, CLONE_NEWNET);
4220 if (r == -EPERM)
4221 log_unit_warning_errno(unit, r,
4222 "PrivateNetwork=yes is configured, but network namespace setup failed, ignoring: %m");
4223 else if (r < 0) {
4224 *exit_status = EXIT_NETWORK;
4225 return log_unit_error_errno(unit, r, "Failed to set up network namespacing: %m");
4226 }
4227 } else if (context->network_namespace_path) {
4228 *exit_status = EXIT_NETWORK;
4229 return log_unit_error_errno(unit, SYNTHETIC_ERRNO(EOPNOTSUPP),
4230 "NetworkNamespacePath= is not supported, refusing.");
4231 } else
4232 log_unit_warning(unit, "PrivateNetwork=yes is configured, but the kernel does not support network namespaces, ignoring.");
4233 }
4234
4235 if ((context->private_ipc || context->ipc_namespace_path) && runtime && runtime->ipcns_storage_socket[0] >= 0) {
4236
4237 if (ns_type_supported(NAMESPACE_IPC)) {
4238 r = setup_shareable_ns(runtime->ipcns_storage_socket, CLONE_NEWIPC);
4239 if (r == -EPERM)
4240 log_unit_warning_errno(unit, r,
4241 "PrivateIPC=yes is configured, but IPC namespace setup failed, ignoring: %m");
4242 else if (r < 0) {
4243 *exit_status = EXIT_NAMESPACE;
4244 return log_unit_error_errno(unit, r, "Failed to set up IPC namespacing: %m");
4245 }
4246 } else if (context->ipc_namespace_path) {
4247 *exit_status = EXIT_NAMESPACE;
4248 return log_unit_error_errno(unit, SYNTHETIC_ERRNO(EOPNOTSUPP),
4249 "IPCNamespacePath= is not supported, refusing.");
4250 } else
4251 log_unit_warning(unit, "PrivateIPC=yes is configured, but the kernel does not support IPC namespaces, ignoring.");
4252 }
4253
4254 needs_mount_namespace = exec_needs_mount_namespace(context, params, runtime);
4255 if (needs_mount_namespace) {
4256 _cleanup_free_ char *error_path = NULL;
4257
4258 r = apply_mount_namespace(unit, command->flags, context, params, runtime, &error_path);
4259 if (r < 0) {
4260 *exit_status = EXIT_NAMESPACE;
4261 return log_unit_error_errno(unit, r, "Failed to set up mount namespacing%s%s: %m",
4262 error_path ? ": " : "", strempty(error_path));
4263 }
4264 }
4265
4266 if (needs_sandboxing) {
4267 r = apply_protect_hostname(unit, context, exit_status);
4268 if (r < 0)
4269 return r;
4270 }
4271
4272 /* Drop groups as early as possible.
4273 * This needs to be done after PrivateDevices=y setup as device nodes should be owned by the host's root.
4274 * For non-root in a userns, devices will be owned by the user/group before the group change, and nobody. */
4275 if (needs_setuid) {
4276 _cleanup_free_ gid_t *gids_to_enforce = NULL;
4277 int ngids_to_enforce = 0;
4278
4279 ngids_to_enforce = merge_gid_lists(supplementary_gids,
4280 ngids,
4281 gids_after_pam,
4282 ngids_after_pam,
4283 &gids_to_enforce);
4284 if (ngids_to_enforce < 0) {
4285 *exit_status = EXIT_MEMORY;
4286 return log_unit_error_errno(unit,
4287 ngids_to_enforce,
4288 "Failed to merge group lists. Group membership might be incorrect: %m");
4289 }
4290
4291 r = enforce_groups(gid, gids_to_enforce, ngids_to_enforce);
4292 if (r < 0) {
4293 *exit_status = EXIT_GROUP;
4294 return log_unit_error_errno(unit, r, "Changing group credentials failed: %m");
4295 }
4296 }
4297
4298 /* If the user namespace was not set up above, try to do it now.
4299 * It's preferred to set up the user namespace later (after all other namespaces) so as not to be
4300 * restricted by rules pertaining to combining user namspaces with other namespaces (e.g. in the
4301 * case of mount namespaces being less privileged when the mount point list is copied from a
4302 * different user namespace). */
4303
4304 if (needs_sandboxing && context->private_users && !userns_set_up) {
4305 r = setup_private_users(saved_uid, saved_gid, uid, gid);
4306 if (r < 0) {
4307 *exit_status = EXIT_USER;
4308 return log_unit_error_errno(unit, r, "Failed to set up user namespacing: %m");
4309 }
4310 }
4311
4312 /* Now that the mount namespace has been set up and privileges adjusted, let's look for the thing we
4313 * shall execute. */
4314
4315 _cleanup_free_ char *executable = NULL;
4316 _cleanup_close_ int executable_fd = -1;
4317 r = find_executable_full(command->path, false, &executable, &executable_fd);
4318 if (r < 0) {
4319 if (r != -ENOMEM && (command->flags & EXEC_COMMAND_IGNORE_FAILURE)) {
4320 log_unit_struct_errno(unit, LOG_INFO, r,
4321 "MESSAGE_ID=" SD_MESSAGE_SPAWN_FAILED_STR,
4322 LOG_UNIT_INVOCATION_ID(unit),
4323 LOG_UNIT_MESSAGE(unit, "Executable %s missing, skipping: %m",
4324 command->path),
4325 "EXECUTABLE=%s", command->path);
4326 return 0;
4327 }
4328
4329 *exit_status = EXIT_EXEC;
4330
4331 return log_unit_struct_errno(unit, LOG_INFO, r,
4332 "MESSAGE_ID=" SD_MESSAGE_SPAWN_FAILED_STR,
4333 LOG_UNIT_INVOCATION_ID(unit),
4334 LOG_UNIT_MESSAGE(unit, "Failed to locate executable %s: %m",
4335 command->path),
4336 "EXECUTABLE=%s", command->path);
4337 }
4338
4339 r = add_shifted_fd(keep_fds, ELEMENTSOF(keep_fds), &n_keep_fds, executable_fd, &executable_fd);
4340 if (r < 0) {
4341 *exit_status = EXIT_FDS;
4342 return log_unit_error_errno(unit, r, "Failed to shift fd and set FD_CLOEXEC: %m");
4343 }
4344
4345 #if HAVE_SELINUX
4346 if (needs_sandboxing && use_selinux && params->selinux_context_net && socket_fd >= 0) {
4347 r = mac_selinux_get_child_mls_label(socket_fd, executable, context->selinux_context, &mac_selinux_context_net);
4348 if (r < 0) {
4349 *exit_status = EXIT_SELINUX_CONTEXT;
4350 return log_unit_error_errno(unit, r, "Failed to determine SELinux context: %m");
4351 }
4352 }
4353 #endif
4354
4355 /* We repeat the fd closing here, to make sure that nothing is leaked from the PAM modules. Note that we are
4356 * more aggressive this time since socket_fd and the netns and ipcns fds we don't need anymore. We do keep the exec_fd
4357 * however if we have it as we want to keep it open until the final execve(). */
4358
4359 r = close_all_fds(keep_fds, n_keep_fds);
4360 if (r >= 0)
4361 r = shift_fds(fds, n_fds);
4362 if (r >= 0)
4363 r = flags_fds(fds, n_socket_fds, n_storage_fds, context->non_blocking);
4364 if (r < 0) {
4365 *exit_status = EXIT_FDS;
4366 return log_unit_error_errno(unit, r, "Failed to adjust passed file descriptors: %m");
4367 }
4368
4369 /* At this point, the fds we want to pass to the program are all ready and set up, with O_CLOEXEC turned off
4370 * and at the right fd numbers. The are no other fds open, with one exception: the exec_fd if it is defined,
4371 * and it has O_CLOEXEC set, after all we want it to be closed by the execve(), so that our parent knows we
4372 * came this far. */
4373
4374 secure_bits = context->secure_bits;
4375
4376 if (needs_sandboxing) {
4377 uint64_t bset;
4378
4379 /* Set the RTPRIO resource limit to 0, but only if nothing else was explicitly
4380 * requested. (Note this is placed after the general resource limit initialization, see
4381 * above, in order to take precedence.) */
4382 if (context->restrict_realtime && !context->rlimit[RLIMIT_RTPRIO]) {
4383 if (setrlimit(RLIMIT_RTPRIO, &RLIMIT_MAKE_CONST(0)) < 0) {
4384 *exit_status = EXIT_LIMITS;
4385 return log_unit_error_errno(unit, errno, "Failed to adjust RLIMIT_RTPRIO resource limit: %m");
4386 }
4387 }
4388
4389 #if ENABLE_SMACK
4390 /* LSM Smack needs the capability CAP_MAC_ADMIN to change the current execution security context of the
4391 * process. This is the latest place before dropping capabilities. Other MAC context are set later. */
4392 if (use_smack) {
4393 r = setup_smack(context, executable_fd);
4394 if (r < 0) {
4395 *exit_status = EXIT_SMACK_PROCESS_LABEL;
4396 return log_unit_error_errno(unit, r, "Failed to set SMACK process label: %m");
4397 }
4398 }
4399 #endif
4400
4401 bset = context->capability_bounding_set;
4402 /* If the ambient caps hack is enabled (which means the kernel can't do them, and the user asked for
4403 * our magic fallback), then let's add some extra caps, so that the service can drop privs of its own,
4404 * instead of us doing that */
4405 if (needs_ambient_hack)
4406 bset |= (UINT64_C(1) << CAP_SETPCAP) |
4407 (UINT64_C(1) << CAP_SETUID) |
4408 (UINT64_C(1) << CAP_SETGID);
4409
4410 if (!cap_test_all(bset)) {
4411 r = capability_bounding_set_drop(bset, false);
4412 if (r < 0) {
4413 *exit_status = EXIT_CAPABILITIES;
4414 return log_unit_error_errno(unit, r, "Failed to drop capabilities: %m");
4415 }
4416 }
4417
4418 /* Ambient capabilities are cleared during setresuid() (in enforce_user()) even with
4419 * keep-caps set.
4420 * To be able to raise the ambient capabilities after setresuid() they have to be
4421 * added to the inherited set and keep caps has to be set (done in enforce_user()).
4422 * After setresuid() the ambient capabilities can be raised as they are present in
4423 * the permitted and inhertiable set. However it is possible that someone wants to
4424 * set ambient capabilities without changing the user, so we also set the ambient
4425 * capabilities here.
4426 * The requested ambient capabilities are raised in the inheritable set if the
4427 * second argument is true. */
4428 if (!needs_ambient_hack) {
4429 r = capability_ambient_set_apply(context->capability_ambient_set, true);
4430 if (r < 0) {
4431 *exit_status = EXIT_CAPABILITIES;
4432 return log_unit_error_errno(unit, r, "Failed to apply ambient capabilities (before UID change): %m");
4433 }
4434 }
4435 }
4436
4437 /* chroot to root directory first, before we lose the ability to chroot */
4438 r = apply_root_directory(context, params, needs_mount_namespace, exit_status);
4439 if (r < 0)
4440 return log_unit_error_errno(unit, r, "Chrooting to the requested root directory failed: %m");
4441
4442 if (needs_setuid) {
4443 if (uid_is_valid(uid)) {
4444 r = enforce_user(context, uid);
4445 if (r < 0) {
4446 *exit_status = EXIT_USER;
4447 return log_unit_error_errno(unit, r, "Failed to change UID to " UID_FMT ": %m", uid);
4448 }
4449
4450 if (!needs_ambient_hack &&
4451 context->capability_ambient_set != 0) {
4452
4453 /* Raise the ambient capabilities after user change. */
4454 r = capability_ambient_set_apply(context->capability_ambient_set, false);
4455 if (r < 0) {
4456 *exit_status = EXIT_CAPABILITIES;
4457 return log_unit_error_errno(unit, r, "Failed to apply ambient capabilities (after UID change): %m");
4458 }
4459 }
4460 }
4461 }
4462
4463 /* Apply working directory here, because the working directory might be on NFS and only the user running
4464 * this service might have the correct privilege to change to the working directory */
4465 r = apply_working_directory(context, params, home, exit_status);
4466 if (r < 0)
4467 return log_unit_error_errno(unit, r, "Changing to the requested working directory failed: %m");
4468
4469 if (needs_sandboxing) {
4470 /* Apply other MAC contexts late, but before seccomp syscall filtering, as those should really be last to
4471 * influence our own codepaths as little as possible. Moreover, applying MAC contexts usually requires
4472 * syscalls that are subject to seccomp filtering, hence should probably be applied before the syscalls
4473 * are restricted. */
4474
4475 #if HAVE_SELINUX
4476 if (use_selinux) {
4477 char *exec_context = mac_selinux_context_net ?: context->selinux_context;
4478
4479 if (exec_context) {
4480 r = setexeccon(exec_context);
4481 if (r < 0) {
4482 *exit_status = EXIT_SELINUX_CONTEXT;
4483 return log_unit_error_errno(unit, r, "Failed to change SELinux context to %s: %m", exec_context);
4484 }
4485 }
4486 }
4487 #endif
4488
4489 #if HAVE_APPARMOR
4490 if (use_apparmor && context->apparmor_profile) {
4491 r = aa_change_onexec(context->apparmor_profile);
4492 if (r < 0 && !context->apparmor_profile_ignore) {
4493 *exit_status = EXIT_APPARMOR_PROFILE;
4494 return log_unit_error_errno(unit, errno, "Failed to prepare AppArmor profile change to %s: %m", context->apparmor_profile);
4495 }
4496 }
4497 #endif
4498
4499 /* PR_GET_SECUREBITS is not privileged, while PR_SET_SECUREBITS is. So to suppress potential EPERMs
4500 * we'll try not to call PR_SET_SECUREBITS unless necessary. Setting securebits requires
4501 * CAP_SETPCAP. */
4502 if (prctl(PR_GET_SECUREBITS) != secure_bits) {
4503 /* CAP_SETPCAP is required to set securebits. This capability is raised into the
4504 * effective set here.
4505 * The effective set is overwritten during execve with the following values:
4506 * - ambient set (for non-root processes)
4507 * - (inheritable | bounding) set for root processes)
4508 *
4509 * Hence there is no security impact to raise it in the effective set before execve
4510 */
4511 r = capability_gain_cap_setpcap(NULL);
4512 if (r < 0) {
4513 *exit_status = EXIT_CAPABILITIES;
4514 return log_unit_error_errno(unit, r, "Failed to gain CAP_SETPCAP for setting secure bits");
4515 }
4516 if (prctl(PR_SET_SECUREBITS, secure_bits) < 0) {
4517 *exit_status = EXIT_SECUREBITS;
4518 return log_unit_error_errno(unit, errno, "Failed to set process secure bits: %m");
4519 }
4520 }
4521
4522 if (context_has_no_new_privileges(context))
4523 if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) < 0) {
4524 *exit_status = EXIT_NO_NEW_PRIVILEGES;
4525 return log_unit_error_errno(unit, errno, "Failed to disable new privileges: %m");
4526 }
4527
4528 #if HAVE_SECCOMP
4529 r = apply_address_families(unit, context);
4530 if (r < 0) {
4531 *exit_status = EXIT_ADDRESS_FAMILIES;
4532 return log_unit_error_errno(unit, r, "Failed to restrict address families: %m");
4533 }
4534
4535 r = apply_memory_deny_write_execute(unit, context);
4536 if (r < 0) {
4537 *exit_status = EXIT_SECCOMP;
4538 return log_unit_error_errno(unit, r, "Failed to disable writing to executable memory: %m");
4539 }
4540
4541 r = apply_restrict_realtime(unit, context);
4542 if (r < 0) {
4543 *exit_status = EXIT_SECCOMP;
4544 return log_unit_error_errno(unit, r, "Failed to apply realtime restrictions: %m");
4545 }
4546
4547 r = apply_restrict_suid_sgid(unit, context);
4548 if (r < 0) {
4549 *exit_status = EXIT_SECCOMP;
4550 return log_unit_error_errno(unit, r, "Failed to apply SUID/SGID restrictions: %m");
4551 }
4552
4553 r = apply_restrict_namespaces(unit, context);
4554 if (r < 0) {
4555 *exit_status = EXIT_SECCOMP;
4556 return log_unit_error_errno(unit, r, "Failed to apply namespace restrictions: %m");
4557 }
4558
4559 r = apply_protect_sysctl(unit, context);
4560 if (r < 0) {
4561 *exit_status = EXIT_SECCOMP;
4562 return log_unit_error_errno(unit, r, "Failed to apply sysctl restrictions: %m");
4563 }
4564
4565 r = apply_protect_kernel_modules(unit, context);
4566 if (r < 0) {
4567 *exit_status = EXIT_SECCOMP;
4568 return log_unit_error_errno(unit, r, "Failed to apply module loading restrictions: %m");
4569 }
4570
4571 r = apply_protect_kernel_logs(unit, context);
4572 if (r < 0) {
4573 *exit_status = EXIT_SECCOMP;
4574 return log_unit_error_errno(unit, r, "Failed to apply kernel log restrictions: %m");
4575 }
4576
4577 r = apply_protect_clock(unit, context);
4578 if (r < 0) {
4579 *exit_status = EXIT_SECCOMP;
4580 return log_unit_error_errno(unit, r, "Failed to apply clock restrictions: %m");
4581 }
4582
4583 r = apply_private_devices(unit, context);
4584 if (r < 0) {
4585 *exit_status = EXIT_SECCOMP;
4586 return log_unit_error_errno(unit, r, "Failed to set up private devices: %m");
4587 }
4588
4589 r = apply_syscall_archs(unit, context);
4590 if (r < 0) {
4591 *exit_status = EXIT_SECCOMP;
4592 return log_unit_error_errno(unit, r, "Failed to apply syscall architecture restrictions: %m");
4593 }
4594
4595 r = apply_lock_personality(unit, context);
4596 if (r < 0) {
4597 *exit_status = EXIT_SECCOMP;
4598 return log_unit_error_errno(unit, r, "Failed to lock personalities: %m");
4599 }
4600
4601 r = apply_syscall_log(unit, context);
4602 if (r < 0) {
4603 *exit_status = EXIT_SECCOMP;
4604 return log_unit_error_errno(unit, r, "Failed to apply system call log filters: %m");
4605 }
4606
4607 /* This really should remain the last step before the execve(), to make sure our own code is unaffected
4608 * by the filter as little as possible. */
4609 r = apply_syscall_filter(unit, context, needs_ambient_hack);
4610 if (r < 0) {
4611 *exit_status = EXIT_SECCOMP;
4612 return log_unit_error_errno(unit, r, "Failed to apply system call filters: %m");
4613 }
4614 #endif
4615 }
4616
4617 if (!strv_isempty(context->unset_environment)) {
4618 char **ee = NULL;
4619
4620 ee = strv_env_delete(accum_env, 1, context->unset_environment);
4621 if (!ee) {
4622 *exit_status = EXIT_MEMORY;
4623 return log_oom();
4624 }
4625
4626 strv_free_and_replace(accum_env, ee);
4627 }
4628
4629 if (!FLAGS_SET(command->flags, EXEC_COMMAND_NO_ENV_EXPAND)) {
4630 replaced_argv = replace_env_argv(command->argv, accum_env);
4631 if (!replaced_argv) {
4632 *exit_status = EXIT_MEMORY;
4633 return log_oom();
4634 }
4635 final_argv = replaced_argv;
4636 } else
4637 final_argv = command->argv;
4638
4639 if (DEBUG_LOGGING) {
4640 _cleanup_free_ char *line = NULL;
4641
4642 line = exec_command_line(final_argv);
4643 if (line)
4644 log_unit_struct(unit, LOG_DEBUG,
4645 "EXECUTABLE=%s", executable,
4646 LOG_UNIT_MESSAGE(unit, "Executing: %s", line),
4647 LOG_UNIT_INVOCATION_ID(unit));
4648 }
4649
4650 if (exec_fd >= 0) {
4651 uint8_t hot = 1;
4652
4653 /* We have finished with all our initializations. Let's now let the manager know that. From this point
4654 * on, if the manager sees POLLHUP on the exec_fd, then execve() was successful. */
4655
4656 if (write(exec_fd, &hot, sizeof(hot)) < 0) {
4657 *exit_status = EXIT_EXEC;
4658 return log_unit_error_errno(unit, errno, "Failed to enable exec_fd: %m");
4659 }
4660 }
4661
4662 r = fexecve_or_execve(executable_fd, executable, final_argv, accum_env);
4663
4664 if (exec_fd >= 0) {
4665 uint8_t hot = 0;
4666
4667 /* The execve() failed. This means the exec_fd is still open. Which means we need to tell the manager
4668 * that POLLHUP on it no longer means execve() succeeded. */
4669
4670 if (write(exec_fd, &hot, sizeof(hot)) < 0) {
4671 *exit_status = EXIT_EXEC;
4672 return log_unit_error_errno(unit, errno, "Failed to disable exec_fd: %m");
4673 }
4674 }
4675
4676 *exit_status = EXIT_EXEC;
4677 return log_unit_error_errno(unit, r, "Failed to execute %s: %m", executable);
4678 }
4679
4680 static int exec_context_load_environment(const Unit *unit, const ExecContext *c, char ***l);
4681 static int exec_context_named_iofds(const ExecContext *c, const ExecParameters *p, int named_iofds[static 3]);
4682
4683 int exec_spawn(Unit *unit,
4684 ExecCommand *command,
4685 const ExecContext *context,
4686 const ExecParameters *params,
4687 ExecRuntime *runtime,
4688 DynamicCreds *dcreds,
4689 pid_t *ret) {
4690
4691 int socket_fd, r, named_iofds[3] = { -1, -1, -1 }, *fds = NULL;
4692 _cleanup_free_ char *subcgroup_path = NULL;
4693 _cleanup_strv_free_ char **files_env = NULL;
4694 size_t n_storage_fds = 0, n_socket_fds = 0;
4695 _cleanup_free_ char *line = NULL;
4696 pid_t pid;
4697
4698 assert(unit);
4699 assert(command);
4700 assert(context);
4701 assert(ret);
4702 assert(params);
4703 assert(params->fds || (params->n_socket_fds + params->n_storage_fds <= 0));
4704
4705 if (context->std_input == EXEC_INPUT_SOCKET ||
4706 context->std_output == EXEC_OUTPUT_SOCKET ||
4707 context->std_error == EXEC_OUTPUT_SOCKET) {
4708
4709 if (params->n_socket_fds > 1)
4710 return log_unit_error_errno(unit, SYNTHETIC_ERRNO(EINVAL), "Got more than one socket.");
4711
4712 if (params->n_socket_fds == 0)
4713 return log_unit_error_errno(unit, SYNTHETIC_ERRNO(EINVAL), "Got no socket.");
4714
4715 socket_fd = params->fds[0];
4716 } else {
4717 socket_fd = -1;
4718 fds = params->fds;
4719 n_socket_fds = params->n_socket_fds;
4720 n_storage_fds = params->n_storage_fds;
4721 }
4722
4723 r = exec_context_named_iofds(context, params, named_iofds);
4724 if (r < 0)
4725 return log_unit_error_errno(unit, r, "Failed to load a named file descriptor: %m");
4726
4727 r = exec_context_load_environment(unit, context, &files_env);
4728 if (r < 0)
4729 return log_unit_error_errno(unit, r, "Failed to load environment files: %m");
4730
4731 line = exec_command_line(command->argv);
4732 if (!line)
4733 return log_oom();
4734
4735 /* Fork with up-to-date SELinux label database, so the child inherits the up-to-date db
4736 and, until the next SELinux policy changes, we save further reloads in future children. */
4737 mac_selinux_maybe_reload();
4738
4739 log_unit_struct(unit, LOG_DEBUG,
4740 LOG_UNIT_MESSAGE(unit, "About to execute %s", line),
4741 "EXECUTABLE=%s", command->path, /* We won't know the real executable path until we create
4742 the mount namespace in the child, but we want to log
4743 from the parent, so we need to use the (possibly
4744 inaccurate) path here. */
4745 LOG_UNIT_INVOCATION_ID(unit));
4746
4747 if (params->cgroup_path) {
4748 r = exec_parameters_get_cgroup_path(params, &subcgroup_path);
4749 if (r < 0)
4750 return log_unit_error_errno(unit, r, "Failed to acquire subcgroup path: %m");
4751 if (r > 0) { /* We are using a child cgroup */
4752 r = cg_create(SYSTEMD_CGROUP_CONTROLLER, subcgroup_path);
4753 if (r < 0)
4754 return log_unit_error_errno(unit, r, "Failed to create control group '%s': %m", subcgroup_path);
4755
4756 /* Normally we would not propagate the oomd xattrs to children but since we created this
4757 * sub-cgroup internally we should do it. */
4758 cgroup_oomd_xattr_apply(unit, subcgroup_path);
4759 }
4760 }
4761
4762 pid = fork();
4763 if (pid < 0)
4764 return log_unit_error_errno(unit, errno, "Failed to fork: %m");
4765
4766 if (pid == 0) {
4767 int exit_status = EXIT_SUCCESS;
4768
4769 r = exec_child(unit,
4770 command,
4771 context,
4772 params,
4773 runtime,
4774 dcreds,
4775 socket_fd,
4776 named_iofds,
4777 fds,
4778 n_socket_fds,
4779 n_storage_fds,
4780 files_env,
4781 unit->manager->user_lookup_fds[1],
4782 &exit_status);
4783
4784 if (r < 0) {
4785 const char *status =
4786 exit_status_to_string(exit_status,
4787 EXIT_STATUS_LIBC | EXIT_STATUS_SYSTEMD);
4788
4789 log_unit_struct_errno(unit, LOG_ERR, r,
4790 "MESSAGE_ID=" SD_MESSAGE_SPAWN_FAILED_STR,
4791 LOG_UNIT_INVOCATION_ID(unit),
4792 LOG_UNIT_MESSAGE(unit, "Failed at step %s spawning %s: %m",
4793 status, command->path),
4794 "EXECUTABLE=%s", command->path);
4795 }
4796
4797 _exit(exit_status);
4798 }
4799
4800 log_unit_debug(unit, "Forked %s as "PID_FMT, command->path, pid);
4801
4802 /* We add the new process to the cgroup both in the child (so that we can be sure that no user code is ever
4803 * executed outside of the cgroup) and in the parent (so that we can be sure that when we kill the cgroup the
4804 * process will be killed too). */
4805 if (subcgroup_path)
4806 (void) cg_attach(SYSTEMD_CGROUP_CONTROLLER, subcgroup_path, pid);
4807
4808 exec_status_start(&command->exec_status, pid);
4809
4810 *ret = pid;
4811 return 0;
4812 }
4813
4814 void exec_context_init(ExecContext *c) {
4815 assert(c);
4816
4817 c->umask = 0022;
4818 c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
4819 c->cpu_sched_policy = SCHED_OTHER;
4820 c->syslog_priority = LOG_DAEMON|LOG_INFO;
4821 c->syslog_level_prefix = true;
4822 c->ignore_sigpipe = true;
4823 c->timer_slack_nsec = NSEC_INFINITY;
4824 c->personality = PERSONALITY_INVALID;
4825 for (ExecDirectoryType t = 0; t < _EXEC_DIRECTORY_TYPE_MAX; t++)
4826 c->directories[t].mode = 0755;
4827 c->timeout_clean_usec = USEC_INFINITY;
4828 c->capability_bounding_set = CAP_ALL;
4829 assert_cc(NAMESPACE_FLAGS_INITIAL != NAMESPACE_FLAGS_ALL);
4830 c->restrict_namespaces = NAMESPACE_FLAGS_INITIAL;
4831 c->log_level_max = -1;
4832 #if HAVE_SECCOMP
4833 c->syscall_errno = SECCOMP_ERROR_NUMBER_KILL;
4834 #endif
4835 numa_policy_reset(&c->numa_policy);
4836 }
4837
4838 void exec_context_done(ExecContext *c) {
4839 assert(c);
4840
4841 c->environment = strv_free(c->environment);
4842 c->environment_files = strv_free(c->environment_files);
4843 c->pass_environment = strv_free(c->pass_environment);
4844 c->unset_environment = strv_free(c->unset_environment);
4845
4846 rlimit_free_all(c->rlimit);
4847
4848 for (size_t l = 0; l < 3; l++) {
4849 c->stdio_fdname[l] = mfree(c->stdio_fdname[l]);
4850 c->stdio_file[l] = mfree(c->stdio_file[l]);
4851 }
4852
4853 c->working_directory = mfree(c->working_directory);
4854 c->root_directory = mfree(c->root_directory);
4855 c->root_image = mfree(c->root_image);
4856 c->root_image_options = mount_options_free_all(c->root_image_options);
4857 c->root_hash = mfree(c->root_hash);
4858 c->root_hash_size = 0;
4859 c->root_hash_path = mfree(c->root_hash_path);
4860 c->root_hash_sig = mfree(c->root_hash_sig);
4861 c->root_hash_sig_size = 0;
4862 c->root_hash_sig_path = mfree(c->root_hash_sig_path);
4863 c->root_verity = mfree(c->root_verity);
4864 c->extension_images = mount_image_free_many(c->extension_images, &c->n_extension_images);
4865 c->tty_path = mfree(c->tty_path);
4866 c->syslog_identifier = mfree(c->syslog_identifier);
4867 c->user = mfree(c->user);
4868 c->group = mfree(c->group);
4869
4870 c->supplementary_groups = strv_free(c->supplementary_groups);
4871
4872 c->pam_name = mfree(c->pam_name);
4873
4874 c->read_only_paths = strv_free(c->read_only_paths);
4875 c->read_write_paths = strv_free(c->read_write_paths);
4876 c->inaccessible_paths = strv_free(c->inaccessible_paths);
4877 c->exec_paths = strv_free(c->exec_paths);
4878 c->no_exec_paths = strv_free(c->no_exec_paths);
4879
4880 bind_mount_free_many(c->bind_mounts, c->n_bind_mounts);
4881 c->bind_mounts = NULL;
4882 c->n_bind_mounts = 0;
4883 temporary_filesystem_free_many(c->temporary_filesystems, c->n_temporary_filesystems);
4884 c->temporary_filesystems = NULL;
4885 c->n_temporary_filesystems = 0;
4886 c->mount_images = mount_image_free_many(c->mount_images, &c->n_mount_images);
4887
4888 cpu_set_reset(&c->cpu_set);
4889 numa_policy_reset(&c->numa_policy);
4890
4891 c->utmp_id = mfree(c->utmp_id);
4892 c->selinux_context = mfree(c->selinux_context);
4893 c->apparmor_profile = mfree(c->apparmor_profile);
4894 c->smack_process_label = mfree(c->smack_process_label);
4895
4896 c->syscall_filter = hashmap_free(c->syscall_filter);
4897 c->syscall_archs = set_free(c->syscall_archs);
4898 c->address_families = set_free(c->address_families);
4899
4900 for (ExecDirectoryType t = 0; t < _EXEC_DIRECTORY_TYPE_MAX; t++)
4901 c->directories[t].paths = strv_free(c->directories[t].paths);
4902
4903 c->log_level_max = -1;
4904
4905 exec_context_free_log_extra_fields(c);
4906
4907 c->log_ratelimit_interval_usec = 0;
4908 c->log_ratelimit_burst = 0;
4909
4910 c->stdin_data = mfree(c->stdin_data);
4911 c->stdin_data_size = 0;
4912
4913 c->network_namespace_path = mfree(c->network_namespace_path);
4914 c->ipc_namespace_path = mfree(c->ipc_namespace_path);
4915
4916 c->log_namespace = mfree(c->log_namespace);
4917
4918 c->load_credentials = strv_free(c->load_credentials);
4919 c->set_credentials = hashmap_free(c->set_credentials);
4920 }
4921
4922 int exec_context_destroy_runtime_directory(const ExecContext *c, const char *runtime_prefix) {
4923 char **i;
4924
4925 assert(c);
4926
4927 if (!runtime_prefix)
4928 return 0;
4929
4930 STRV_FOREACH(i, c->directories[EXEC_DIRECTORY_RUNTIME].paths) {
4931 _cleanup_free_ char *p = NULL;
4932
4933 if (exec_directory_is_private(c, EXEC_DIRECTORY_RUNTIME))
4934 p = path_join(runtime_prefix, "private", *i);
4935 else
4936 p = path_join(runtime_prefix, *i);
4937 if (!p)
4938 return -ENOMEM;
4939
4940 /* We execute this synchronously, since we need to be sure this is gone when we start the
4941 * service next. */
4942 (void) rm_rf(p, REMOVE_ROOT);
4943 }
4944
4945 return 0;
4946 }
4947
4948 int exec_context_destroy_credentials(const ExecContext *c, const char *runtime_prefix, const char *unit) {
4949 _cleanup_free_ char *p = NULL;
4950
4951 assert(c);
4952
4953 if (!runtime_prefix || !unit)
4954 return 0;
4955
4956 p = path_join(runtime_prefix, "credentials", unit);
4957 if (!p)
4958 return -ENOMEM;
4959
4960 /* This is either a tmpfs/ramfs of its own, or a plain directory. Either way, let's first try to
4961 * unmount it, and afterwards remove the mount point */
4962 (void) umount2(p, MNT_DETACH|UMOUNT_NOFOLLOW);
4963 (void) rm_rf(p, REMOVE_ROOT|REMOVE_CHMOD);
4964
4965 return 0;
4966 }
4967
4968 static void exec_command_done(ExecCommand *c) {
4969 assert(c);
4970
4971 c->path = mfree(c->path);
4972 c->argv = strv_free(c->argv);
4973 }
4974
4975 void exec_command_done_array(ExecCommand *c, size_t n) {
4976 for (size_t i = 0; i < n; i++)
4977 exec_command_done(c+i);
4978 }
4979
4980 ExecCommand* exec_command_free_list(ExecCommand *c) {
4981 ExecCommand *i;
4982
4983 while ((i = c)) {
4984 LIST_REMOVE(command, c, i);
4985 exec_command_done(i);
4986 free(i);
4987 }
4988
4989 return NULL;
4990 }
4991
4992 void exec_command_free_array(ExecCommand **c, size_t n) {
4993 for (size_t i = 0; i < n; i++)
4994 c[i] = exec_command_free_list(c[i]);
4995 }
4996
4997 void exec_command_reset_status_array(ExecCommand *c, size_t n) {
4998 for (size_t i = 0; i < n; i++)
4999 exec_status_reset(&c[i].exec_status);
5000 }
5001
5002 void exec_command_reset_status_list_array(ExecCommand **c, size_t n) {
5003 for (size_t i = 0; i < n; i++) {
5004 ExecCommand *z;
5005
5006 LIST_FOREACH(command, z, c[i])
5007 exec_status_reset(&z->exec_status);
5008 }
5009 }
5010
5011 typedef struct InvalidEnvInfo {
5012 const Unit *unit;
5013 const char *path;
5014 } InvalidEnvInfo;
5015
5016 static void invalid_env(const char *p, void *userdata) {
5017 InvalidEnvInfo *info = userdata;
5018
5019 log_unit_error(info->unit, "Ignoring invalid environment assignment '%s': %s", p, info->path);
5020 }
5021
5022 const char* exec_context_fdname(const ExecContext *c, int fd_index) {
5023 assert(c);
5024
5025 switch (fd_index) {
5026
5027 case STDIN_FILENO:
5028 if (c->std_input != EXEC_INPUT_NAMED_FD)
5029 return NULL;
5030
5031 return c->stdio_fdname[STDIN_FILENO] ?: "stdin";
5032
5033 case STDOUT_FILENO:
5034 if (c->std_output != EXEC_OUTPUT_NAMED_FD)
5035 return NULL;
5036
5037 return c->stdio_fdname[STDOUT_FILENO] ?: "stdout";
5038
5039 case STDERR_FILENO:
5040 if (c->std_error != EXEC_OUTPUT_NAMED_FD)
5041 return NULL;
5042
5043 return c->stdio_fdname[STDERR_FILENO] ?: "stderr";
5044
5045 default:
5046 return NULL;
5047 }
5048 }
5049
5050 static int exec_context_named_iofds(
5051 const ExecContext *c,
5052 const ExecParameters *p,
5053 int named_iofds[static 3]) {
5054
5055 size_t targets;
5056 const char* stdio_fdname[3];
5057 size_t n_fds;
5058
5059 assert(c);
5060 assert(p);
5061 assert(named_iofds);
5062
5063 targets = (c->std_input == EXEC_INPUT_NAMED_FD) +
5064 (c->std_output == EXEC_OUTPUT_NAMED_FD) +
5065 (c->std_error == EXEC_OUTPUT_NAMED_FD);
5066
5067 for (size_t i = 0; i < 3; i++)
5068 stdio_fdname[i] = exec_context_fdname(c, i);
5069
5070 n_fds = p->n_storage_fds + p->n_socket_fds;
5071
5072 for (size_t i = 0; i < n_fds && targets > 0; i++)
5073 if (named_iofds[STDIN_FILENO] < 0 &&
5074 c->std_input == EXEC_INPUT_NAMED_FD &&
5075 stdio_fdname[STDIN_FILENO] &&
5076 streq(p->fd_names[i], stdio_fdname[STDIN_FILENO])) {
5077
5078 named_iofds[STDIN_FILENO] = p->fds[i];
5079 targets--;
5080
5081 } else if (named_iofds[STDOUT_FILENO] < 0 &&
5082 c->std_output == EXEC_OUTPUT_NAMED_FD &&
5083 stdio_fdname[STDOUT_FILENO] &&
5084 streq(p->fd_names[i], stdio_fdname[STDOUT_FILENO])) {
5085
5086 named_iofds[STDOUT_FILENO] = p->fds[i];
5087 targets--;
5088
5089 } else if (named_iofds[STDERR_FILENO] < 0 &&
5090 c->std_error == EXEC_OUTPUT_NAMED_FD &&
5091 stdio_fdname[STDERR_FILENO] &&
5092 streq(p->fd_names[i], stdio_fdname[STDERR_FILENO])) {
5093
5094 named_iofds[STDERR_FILENO] = p->fds[i];
5095 targets--;
5096 }
5097
5098 return targets == 0 ? 0 : -ENOENT;
5099 }
5100
5101 static int exec_context_load_environment(const Unit *unit, const ExecContext *c, char ***l) {
5102 char **i, **r = NULL;
5103
5104 assert(c);
5105 assert(l);
5106
5107 STRV_FOREACH(i, c->environment_files) {
5108 char *fn;
5109 int k;
5110 bool ignore = false;
5111 char **p;
5112 _cleanup_globfree_ glob_t pglob = {};
5113
5114 fn = *i;
5115
5116 if (fn[0] == '-') {
5117 ignore = true;
5118 fn++;
5119 }
5120
5121 if (!path_is_absolute(fn)) {
5122 if (ignore)
5123 continue;
5124
5125 strv_free(r);
5126 return -EINVAL;
5127 }
5128
5129 /* Filename supports globbing, take all matching files */
5130 k = safe_glob(fn, 0, &pglob);
5131 if (k < 0) {
5132 if (ignore)
5133 continue;
5134
5135 strv_free(r);
5136 return k;
5137 }
5138
5139 /* When we don't match anything, -ENOENT should be returned */
5140 assert(pglob.gl_pathc > 0);
5141
5142 for (unsigned n = 0; n < pglob.gl_pathc; n++) {
5143 k = load_env_file(NULL, pglob.gl_pathv[n], &p);
5144 if (k < 0) {
5145 if (ignore)
5146 continue;
5147
5148 strv_free(r);
5149 return k;
5150 }
5151 /* Log invalid environment variables with filename */
5152 if (p) {
5153 InvalidEnvInfo info = {
5154 .unit = unit,
5155 .path = pglob.gl_pathv[n]
5156 };
5157
5158 p = strv_env_clean_with_callback(p, invalid_env, &info);
5159 }
5160
5161 if (!r)
5162 r = p;
5163 else {
5164 char **m;
5165
5166 m = strv_env_merge(2, r, p);
5167 strv_free(r);
5168 strv_free(p);
5169 if (!m)
5170 return -ENOMEM;
5171
5172 r = m;
5173 }
5174 }
5175 }
5176
5177 *l = r;
5178
5179 return 0;
5180 }
5181
5182 static bool tty_may_match_dev_console(const char *tty) {
5183 _cleanup_free_ char *resolved = NULL;
5184
5185 if (!tty)
5186 return true;
5187
5188 tty = skip_dev_prefix(tty);
5189
5190 /* trivial identity? */
5191 if (streq(tty, "console"))
5192 return true;
5193
5194 if (resolve_dev_console(&resolved) < 0)
5195 return true; /* if we could not resolve, assume it may */
5196
5197 /* "tty0" means the active VC, so it may be the same sometimes */
5198 return path_equal(resolved, tty) || (streq(resolved, "tty0") && tty_is_vc(tty));
5199 }
5200
5201 static bool exec_context_may_touch_tty(const ExecContext *ec) {
5202 assert(ec);
5203
5204 return ec->tty_reset ||
5205 ec->tty_vhangup ||
5206 ec->tty_vt_disallocate ||
5207 is_terminal_input(ec->std_input) ||
5208 is_terminal_output(ec->std_output) ||
5209 is_terminal_output(ec->std_error);
5210 }
5211
5212 bool exec_context_may_touch_console(const ExecContext *ec) {
5213
5214 return exec_context_may_touch_tty(ec) &&
5215 tty_may_match_dev_console(exec_context_tty_path(ec));
5216 }
5217
5218 static void strv_fprintf(FILE *f, char **l) {
5219 char **g;
5220
5221 assert(f);
5222
5223 STRV_FOREACH(g, l)
5224 fprintf(f, " %s", *g);
5225 }
5226
5227 static void strv_dump(FILE* f, const char *prefix, const char *name, char **strv) {
5228 assert(f);
5229 assert(prefix);
5230 assert(name);
5231
5232 if (!strv_isempty(strv)) {
5233 fprintf(f, "%s%s:", prefix, name);
5234 strv_fprintf(f, strv);
5235 fputs("\n", f);
5236 }
5237 }
5238
5239 void exec_context_dump(const ExecContext *c, FILE* f, const char *prefix) {
5240 char **e, **d, buf_clean[FORMAT_TIMESPAN_MAX];
5241 int r;
5242
5243 assert(c);
5244 assert(f);
5245
5246 prefix = strempty(prefix);
5247
5248 fprintf(f,
5249 "%sUMask: %04o\n"
5250 "%sWorkingDirectory: %s\n"
5251 "%sRootDirectory: %s\n"
5252 "%sNonBlocking: %s\n"
5253 "%sPrivateTmp: %s\n"
5254 "%sPrivateDevices: %s\n"
5255 "%sProtectKernelTunables: %s\n"
5256 "%sProtectKernelModules: %s\n"
5257 "%sProtectKernelLogs: %s\n"
5258 "%sProtectClock: %s\n"
5259 "%sProtectControlGroups: %s\n"
5260 "%sPrivateNetwork: %s\n"
5261 "%sPrivateUsers: %s\n"
5262 "%sProtectHome: %s\n"
5263 "%sProtectSystem: %s\n"
5264 "%sMountAPIVFS: %s\n"
5265 "%sIgnoreSIGPIPE: %s\n"
5266 "%sMemoryDenyWriteExecute: %s\n"
5267 "%sRestrictRealtime: %s\n"
5268 "%sRestrictSUIDSGID: %s\n"
5269 "%sKeyringMode: %s\n"
5270 "%sProtectHostname: %s\n"
5271 "%sProtectProc: %s\n"
5272 "%sProcSubset: %s\n",
5273 prefix, c->umask,
5274 prefix, empty_to_root(c->working_directory),
5275 prefix, empty_to_root(c->root_directory),
5276 prefix, yes_no(c->non_blocking),
5277 prefix, yes_no(c->private_tmp),
5278 prefix, yes_no(c->private_devices),
5279 prefix, yes_no(c->protect_kernel_tunables),
5280 prefix, yes_no(c->protect_kernel_modules),
5281 prefix, yes_no(c->protect_kernel_logs),
5282 prefix, yes_no(c->protect_clock),
5283 prefix, yes_no(c->protect_control_groups),
5284 prefix, yes_no(c->private_network),
5285 prefix, yes_no(c->private_users),
5286 prefix, protect_home_to_string(c->protect_home),
5287 prefix, protect_system_to_string(c->protect_system),
5288 prefix, yes_no(exec_context_get_effective_mount_apivfs(c)),
5289 prefix, yes_no(c->ignore_sigpipe),
5290 prefix, yes_no(c->memory_deny_write_execute),
5291 prefix, yes_no(c->restrict_realtime),
5292 prefix, yes_no(c->restrict_suid_sgid),
5293 prefix, exec_keyring_mode_to_string(c->keyring_mode),
5294 prefix, yes_no(c->protect_hostname),
5295 prefix, protect_proc_to_string(c->protect_proc),
5296 prefix, proc_subset_to_string(c->proc_subset));
5297
5298 if (c->root_image)
5299 fprintf(f, "%sRootImage: %s\n", prefix, c->root_image);
5300
5301 if (c->root_image_options) {
5302 MountOptions *o;
5303
5304 fprintf(f, "%sRootImageOptions:", prefix);
5305 LIST_FOREACH(mount_options, o, c->root_image_options)
5306 if (!isempty(o->options))
5307 fprintf(f, " %s:%s",
5308 partition_designator_to_string(o->partition_designator),
5309 o->options);
5310 fprintf(f, "\n");
5311 }
5312
5313 if (c->root_hash) {
5314 _cleanup_free_ char *encoded = NULL;
5315 encoded = hexmem(c->root_hash, c->root_hash_size);
5316 if (encoded)
5317 fprintf(f, "%sRootHash: %s\n", prefix, encoded);
5318 }
5319
5320 if (c->root_hash_path)
5321 fprintf(f, "%sRootHash: %s\n", prefix, c->root_hash_path);
5322
5323 if (c->root_hash_sig) {
5324 _cleanup_free_ char *encoded = NULL;
5325 ssize_t len;
5326 len = base64mem(c->root_hash_sig, c->root_hash_sig_size, &encoded);
5327 if (len)
5328 fprintf(f, "%sRootHashSignature: base64:%s\n", prefix, encoded);
5329 }
5330
5331 if (c->root_hash_sig_path)
5332 fprintf(f, "%sRootHashSignature: %s\n", prefix, c->root_hash_sig_path);
5333
5334 if (c->root_verity)
5335 fprintf(f, "%sRootVerity: %s\n", prefix, c->root_verity);
5336
5337 STRV_FOREACH(e, c->environment)
5338 fprintf(f, "%sEnvironment: %s\n", prefix, *e);
5339
5340 STRV_FOREACH(e, c->environment_files)
5341 fprintf(f, "%sEnvironmentFile: %s\n", prefix, *e);
5342
5343 STRV_FOREACH(e, c->pass_environment)
5344 fprintf(f, "%sPassEnvironment: %s\n", prefix, *e);
5345
5346 STRV_FOREACH(e, c->unset_environment)
5347 fprintf(f, "%sUnsetEnvironment: %s\n", prefix, *e);
5348
5349 fprintf(f, "%sRuntimeDirectoryPreserve: %s\n", prefix, exec_preserve_mode_to_string(c->runtime_directory_preserve_mode));
5350
5351 for (ExecDirectoryType dt = 0; dt < _EXEC_DIRECTORY_TYPE_MAX; dt++) {
5352 fprintf(f, "%s%sMode: %04o\n", prefix, exec_directory_type_to_string(dt), c->directories[dt].mode);
5353
5354 STRV_FOREACH(d, c->directories[dt].paths)
5355 fprintf(f, "%s%s: %s\n", prefix, exec_directory_type_to_string(dt), *d);
5356 }
5357
5358 fprintf(f,
5359 "%sTimeoutCleanSec: %s\n",
5360 prefix, format_timespan(buf_clean, sizeof(buf_clean), c->timeout_clean_usec, USEC_PER_SEC));
5361
5362 if (c->nice_set)
5363 fprintf(f,
5364 "%sNice: %i\n",
5365 prefix, c->nice);
5366
5367 if (c->oom_score_adjust_set)
5368 fprintf(f,
5369 "%sOOMScoreAdjust: %i\n",
5370 prefix, c->oom_score_adjust);
5371
5372 if (c->coredump_filter_set)
5373 fprintf(f,
5374 "%sCoredumpFilter: 0x%"PRIx64"\n",
5375 prefix, c->coredump_filter);
5376
5377 for (unsigned i = 0; i < RLIM_NLIMITS; i++)
5378 if (c->rlimit[i]) {
5379 fprintf(f, "%sLimit%s: " RLIM_FMT "\n",
5380 prefix, rlimit_to_string(i), c->rlimit[i]->rlim_max);
5381 fprintf(f, "%sLimit%sSoft: " RLIM_FMT "\n",
5382 prefix, rlimit_to_string(i), c->rlimit[i]->rlim_cur);
5383 }
5384
5385 if (c->ioprio_set) {
5386 _cleanup_free_ char *class_str = NULL;
5387
5388 r = ioprio_class_to_string_alloc(IOPRIO_PRIO_CLASS(c->ioprio), &class_str);
5389 if (r >= 0)
5390 fprintf(f, "%sIOSchedulingClass: %s\n", prefix, class_str);
5391
5392 fprintf(f, "%sIOPriority: %lu\n", prefix, IOPRIO_PRIO_DATA(c->ioprio));
5393 }
5394
5395 if (c->cpu_sched_set) {
5396 _cleanup_free_ char *policy_str = NULL;
5397
5398 r = sched_policy_to_string_alloc(c->cpu_sched_policy, &policy_str);
5399 if (r >= 0)
5400 fprintf(f, "%sCPUSchedulingPolicy: %s\n", prefix, policy_str);
5401
5402 fprintf(f,
5403 "%sCPUSchedulingPriority: %i\n"
5404 "%sCPUSchedulingResetOnFork: %s\n",
5405 prefix, c->cpu_sched_priority,
5406 prefix, yes_no(c->cpu_sched_reset_on_fork));
5407 }
5408
5409 if (c->cpu_set.set) {
5410 _cleanup_free_ char *affinity = NULL;
5411
5412 affinity = cpu_set_to_range_string(&c->cpu_set);
5413 fprintf(f, "%sCPUAffinity: %s\n", prefix, affinity);
5414 }
5415
5416 if (mpol_is_valid(numa_policy_get_type(&c->numa_policy))) {
5417 _cleanup_free_ char *nodes = NULL;
5418
5419 nodes = cpu_set_to_range_string(&c->numa_policy.nodes);
5420 fprintf(f, "%sNUMAPolicy: %s\n", prefix, mpol_to_string(numa_policy_get_type(&c->numa_policy)));
5421 fprintf(f, "%sNUMAMask: %s\n", prefix, strnull(nodes));
5422 }
5423
5424 if (c->timer_slack_nsec != NSEC_INFINITY)
5425 fprintf(f, "%sTimerSlackNSec: "NSEC_FMT "\n", prefix, c->timer_slack_nsec);
5426
5427 fprintf(f,
5428 "%sStandardInput: %s\n"
5429 "%sStandardOutput: %s\n"
5430 "%sStandardError: %s\n",
5431 prefix, exec_input_to_string(c->std_input),
5432 prefix, exec_output_to_string(c->std_output),
5433 prefix, exec_output_to_string(c->std_error));
5434
5435 if (c->std_input == EXEC_INPUT_NAMED_FD)
5436 fprintf(f, "%sStandardInputFileDescriptorName: %s\n", prefix, c->stdio_fdname[STDIN_FILENO]);
5437 if (c->std_output == EXEC_OUTPUT_NAMED_FD)
5438 fprintf(f, "%sStandardOutputFileDescriptorName: %s\n", prefix, c->stdio_fdname[STDOUT_FILENO]);
5439 if (c->std_error == EXEC_OUTPUT_NAMED_FD)
5440 fprintf(f, "%sStandardErrorFileDescriptorName: %s\n", prefix, c->stdio_fdname[STDERR_FILENO]);
5441
5442 if (c->std_input == EXEC_INPUT_FILE)
5443 fprintf(f, "%sStandardInputFile: %s\n", prefix, c->stdio_file[STDIN_FILENO]);
5444 if (c->std_output == EXEC_OUTPUT_FILE)
5445 fprintf(f, "%sStandardOutputFile: %s\n", prefix, c->stdio_file[STDOUT_FILENO]);
5446 if (c->std_output == EXEC_OUTPUT_FILE_APPEND)
5447 fprintf(f, "%sStandardOutputFileToAppend: %s\n", prefix, c->stdio_file[STDOUT_FILENO]);
5448 if (c->std_output == EXEC_OUTPUT_FILE_TRUNCATE)
5449 fprintf(f, "%sStandardOutputFileToTruncate: %s\n", prefix, c->stdio_file[STDOUT_FILENO]);
5450 if (c->std_error == EXEC_OUTPUT_FILE)
5451 fprintf(f, "%sStandardErrorFile: %s\n", prefix, c->stdio_file[STDERR_FILENO]);
5452 if (c->std_error == EXEC_OUTPUT_FILE_APPEND)
5453 fprintf(f, "%sStandardErrorFileToAppend: %s\n", prefix, c->stdio_file[STDERR_FILENO]);
5454 if (c->std_error == EXEC_OUTPUT_FILE_TRUNCATE)
5455 fprintf(f, "%sStandardErrorFileToTruncate: %s\n", prefix, c->stdio_file[STDERR_FILENO]);
5456
5457 if (c->tty_path)
5458 fprintf(f,
5459 "%sTTYPath: %s\n"
5460 "%sTTYReset: %s\n"
5461 "%sTTYVHangup: %s\n"
5462 "%sTTYVTDisallocate: %s\n",
5463 prefix, c->tty_path,
5464 prefix, yes_no(c->tty_reset),
5465 prefix, yes_no(c->tty_vhangup),
5466 prefix, yes_no(c->tty_vt_disallocate));
5467
5468 if (IN_SET(c->std_output,
5469 EXEC_OUTPUT_KMSG,
5470 EXEC_OUTPUT_JOURNAL,
5471 EXEC_OUTPUT_KMSG_AND_CONSOLE,
5472 EXEC_OUTPUT_JOURNAL_AND_CONSOLE) ||
5473 IN_SET(c->std_error,
5474 EXEC_OUTPUT_KMSG,
5475 EXEC_OUTPUT_JOURNAL,
5476 EXEC_OUTPUT_KMSG_AND_CONSOLE,
5477 EXEC_OUTPUT_JOURNAL_AND_CONSOLE)) {
5478
5479 _cleanup_free_ char *fac_str = NULL, *lvl_str = NULL;
5480
5481 r = log_facility_unshifted_to_string_alloc(c->syslog_priority >> 3, &fac_str);
5482 if (r >= 0)
5483 fprintf(f, "%sSyslogFacility: %s\n", prefix, fac_str);
5484
5485 r = log_level_to_string_alloc(LOG_PRI(c->syslog_priority), &lvl_str);
5486 if (r >= 0)
5487 fprintf(f, "%sSyslogLevel: %s\n", prefix, lvl_str);
5488 }
5489
5490 if (c->log_level_max >= 0) {
5491 _cleanup_free_ char *t = NULL;
5492
5493 (void) log_level_to_string_alloc(c->log_level_max, &t);
5494
5495 fprintf(f, "%sLogLevelMax: %s\n", prefix, strna(t));
5496 }
5497
5498 if (c->log_ratelimit_interval_usec > 0) {
5499 char buf_timespan[FORMAT_TIMESPAN_MAX];
5500
5501 fprintf(f,
5502 "%sLogRateLimitIntervalSec: %s\n",
5503 prefix, format_timespan(buf_timespan, sizeof(buf_timespan), c->log_ratelimit_interval_usec, USEC_PER_SEC));
5504 }
5505
5506 if (c->log_ratelimit_burst > 0)
5507 fprintf(f, "%sLogRateLimitBurst: %u\n", prefix, c->log_ratelimit_burst);
5508
5509 for (size_t j = 0; j < c->n_log_extra_fields; j++) {
5510 fprintf(f, "%sLogExtraFields: ", prefix);
5511 fwrite(c->log_extra_fields[j].iov_base,
5512 1, c->log_extra_fields[j].iov_len,
5513 f);
5514 fputc('\n', f);
5515 }
5516
5517 if (c->log_namespace)
5518 fprintf(f, "%sLogNamespace: %s\n", prefix, c->log_namespace);
5519
5520 if (c->secure_bits) {
5521 _cleanup_free_ char *str = NULL;
5522
5523 r = secure_bits_to_string_alloc(c->secure_bits, &str);
5524 if (r >= 0)
5525 fprintf(f, "%sSecure Bits: %s\n", prefix, str);
5526 }
5527
5528 if (c->capability_bounding_set != CAP_ALL) {
5529 _cleanup_free_ char *str = NULL;
5530
5531 r = capability_set_to_string_alloc(c->capability_bounding_set, &str);
5532 if (r >= 0)
5533 fprintf(f, "%sCapabilityBoundingSet: %s\n", prefix, str);
5534 }
5535
5536 if (c->capability_ambient_set != 0) {
5537 _cleanup_free_ char *str = NULL;
5538
5539 r = capability_set_to_string_alloc(c->capability_ambient_set, &str);
5540 if (r >= 0)
5541 fprintf(f, "%sAmbientCapabilities: %s\n", prefix, str);
5542 }
5543
5544 if (c->user)
5545 fprintf(f, "%sUser: %s\n", prefix, c->user);
5546 if (c->group)
5547 fprintf(f, "%sGroup: %s\n", prefix, c->group);
5548
5549 fprintf(f, "%sDynamicUser: %s\n", prefix, yes_no(c->dynamic_user));
5550
5551 strv_dump(f, prefix, "SupplementaryGroups", c->supplementary_groups);
5552
5553 if (c->pam_name)
5554 fprintf(f, "%sPAMName: %s\n", prefix, c->pam_name);
5555
5556 strv_dump(f, prefix, "ReadWritePaths", c->read_write_paths);
5557 strv_dump(f, prefix, "ReadOnlyPaths", c->read_only_paths);
5558 strv_dump(f, prefix, "InaccessiblePaths", c->inaccessible_paths);
5559 strv_dump(f, prefix, "ExecPaths", c->exec_paths);
5560 strv_dump(f, prefix, "NoExecPaths", c->no_exec_paths);
5561
5562 for (size_t i = 0; i < c->n_bind_mounts; i++)
5563 fprintf(f, "%s%s: %s%s:%s:%s\n", prefix,
5564 c->bind_mounts[i].read_only ? "BindReadOnlyPaths" : "BindPaths",
5565 c->bind_mounts[i].ignore_enoent ? "-": "",
5566 c->bind_mounts[i].source,
5567 c->bind_mounts[i].destination,
5568 c->bind_mounts[i].recursive ? "rbind" : "norbind");
5569
5570 for (size_t i = 0; i < c->n_temporary_filesystems; i++) {
5571 const TemporaryFileSystem *t = c->temporary_filesystems + i;
5572
5573 fprintf(f, "%sTemporaryFileSystem: %s%s%s\n", prefix,
5574 t->path,
5575 isempty(t->options) ? "" : ":",
5576 strempty(t->options));
5577 }
5578
5579 if (c->utmp_id)
5580 fprintf(f,
5581 "%sUtmpIdentifier: %s\n",
5582 prefix, c->utmp_id);
5583
5584 if (c->selinux_context)
5585 fprintf(f,
5586 "%sSELinuxContext: %s%s\n",
5587 prefix, c->selinux_context_ignore ? "-" : "", c->selinux_context);
5588
5589 if (c->apparmor_profile)
5590 fprintf(f,
5591 "%sAppArmorProfile: %s%s\n",
5592 prefix, c->apparmor_profile_ignore ? "-" : "", c->apparmor_profile);
5593
5594 if (c->smack_process_label)
5595 fprintf(f,
5596 "%sSmackProcessLabel: %s%s\n",
5597 prefix, c->smack_process_label_ignore ? "-" : "", c->smack_process_label);
5598
5599 if (c->personality != PERSONALITY_INVALID)
5600 fprintf(f,
5601 "%sPersonality: %s\n",
5602 prefix, strna(personality_to_string(c->personality)));
5603
5604 fprintf(f,
5605 "%sLockPersonality: %s\n",
5606 prefix, yes_no(c->lock_personality));
5607
5608 if (c->syscall_filter) {
5609 #if HAVE_SECCOMP
5610 void *id, *val;
5611 bool first = true;
5612 #endif
5613
5614 fprintf(f,
5615 "%sSystemCallFilter: ",
5616 prefix);
5617
5618 if (!c->syscall_allow_list)
5619 fputc('~', f);
5620
5621 #if HAVE_SECCOMP
5622 HASHMAP_FOREACH_KEY(val, id, c->syscall_filter) {
5623 _cleanup_free_ char *name = NULL;
5624 const char *errno_name = NULL;
5625 int num = PTR_TO_INT(val);
5626
5627 if (first)
5628 first = false;
5629 else
5630 fputc(' ', f);
5631
5632 name = seccomp_syscall_resolve_num_arch(SCMP_ARCH_NATIVE, PTR_TO_INT(id) - 1);
5633 fputs(strna(name), f);
5634
5635 if (num >= 0) {
5636 errno_name = seccomp_errno_or_action_to_string(num);
5637 if (errno_name)
5638 fprintf(f, ":%s", errno_name);
5639 else
5640 fprintf(f, ":%d", num);
5641 }
5642 }
5643 #endif
5644
5645 fputc('\n', f);
5646 }
5647
5648 if (c->syscall_archs) {
5649 #if HAVE_SECCOMP
5650 void *id;
5651 #endif
5652
5653 fprintf(f,
5654 "%sSystemCallArchitectures:",
5655 prefix);
5656
5657 #if HAVE_SECCOMP
5658 SET_FOREACH(id, c->syscall_archs)
5659 fprintf(f, " %s", strna(seccomp_arch_to_string(PTR_TO_UINT32(id) - 1)));
5660 #endif
5661 fputc('\n', f);
5662 }
5663
5664 if (exec_context_restrict_namespaces_set(c)) {
5665 _cleanup_free_ char *s = NULL;
5666
5667 r = namespace_flags_to_string(c->restrict_namespaces, &s);
5668 if (r >= 0)
5669 fprintf(f, "%sRestrictNamespaces: %s\n",
5670 prefix, strna(s));
5671 }
5672
5673 if (c->network_namespace_path)
5674 fprintf(f,
5675 "%sNetworkNamespacePath: %s\n",
5676 prefix, c->network_namespace_path);
5677
5678 if (c->syscall_errno > 0) {
5679 #if HAVE_SECCOMP
5680 const char *errno_name;
5681 #endif
5682
5683 fprintf(f, "%sSystemCallErrorNumber: ", prefix);
5684
5685 #if HAVE_SECCOMP
5686 errno_name = seccomp_errno_or_action_to_string(c->syscall_errno);
5687 if (errno_name)
5688 fputs(errno_name, f);
5689 else
5690 fprintf(f, "%d", c->syscall_errno);
5691 #endif
5692 fputc('\n', f);
5693 }
5694
5695 for (size_t i = 0; i < c->n_mount_images; i++) {
5696 MountOptions *o;
5697
5698 fprintf(f, "%sMountImages: %s%s:%s", prefix,
5699 c->mount_images[i].ignore_enoent ? "-": "",
5700 c->mount_images[i].source,
5701 c->mount_images[i].destination);
5702 LIST_FOREACH(mount_options, o, c->mount_images[i].mount_options)
5703 fprintf(f, ":%s:%s",
5704 partition_designator_to_string(o->partition_designator),
5705 strempty(o->options));
5706 fprintf(f, "\n");
5707 }
5708
5709 for (size_t i = 0; i < c->n_extension_images; i++) {
5710 MountOptions *o;
5711
5712 fprintf(f, "%sExtensionImages: %s%s", prefix,
5713 c->extension_images[i].ignore_enoent ? "-": "",
5714 c->extension_images[i].source);
5715 LIST_FOREACH(mount_options, o, c->extension_images[i].mount_options)
5716 fprintf(f, ":%s:%s",
5717 partition_designator_to_string(o->partition_designator),
5718 strempty(o->options));
5719 fprintf(f, "\n");
5720 }
5721 }
5722
5723 bool exec_context_maintains_privileges(const ExecContext *c) {
5724 assert(c);
5725
5726 /* Returns true if the process forked off would run under
5727 * an unchanged UID or as root. */
5728
5729 if (!c->user)
5730 return true;
5731
5732 if (streq(c->user, "root") || streq(c->user, "0"))
5733 return true;
5734
5735 return false;
5736 }
5737
5738 int exec_context_get_effective_ioprio(const ExecContext *c) {
5739 int p;
5740
5741 assert(c);
5742
5743 if (c->ioprio_set)
5744 return c->ioprio;
5745
5746 p = ioprio_get(IOPRIO_WHO_PROCESS, 0);
5747 if (p < 0)
5748 return IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 4);
5749
5750 return p;
5751 }
5752
5753 bool exec_context_get_effective_mount_apivfs(const ExecContext *c) {
5754 assert(c);
5755
5756 /* Explicit setting wins */
5757 if (c->mount_apivfs_set)
5758 return c->mount_apivfs;
5759
5760 /* Default to "yes" if root directory or image are specified */
5761 if (exec_context_with_rootfs(c))
5762 return true;
5763
5764 return false;
5765 }
5766
5767 void exec_context_free_log_extra_fields(ExecContext *c) {
5768 assert(c);
5769
5770 for (size_t l = 0; l < c->n_log_extra_fields; l++)
5771 free(c->log_extra_fields[l].iov_base);
5772 c->log_extra_fields = mfree(c->log_extra_fields);
5773 c->n_log_extra_fields = 0;
5774 }
5775
5776 void exec_context_revert_tty(ExecContext *c) {
5777 _cleanup_close_ int fd = -1;
5778 const char *path;
5779 struct stat st;
5780 int r;
5781
5782 assert(c);
5783
5784 /* First, reset the TTY (possibly kicking everybody else from the TTY) */
5785 exec_context_tty_reset(c, NULL);
5786
5787 /* And then undo what chown_terminal() did earlier. Note that we only do this if we have a path
5788 * configured. If the TTY was passed to us as file descriptor we assume the TTY is opened and managed
5789 * by whoever passed it to us and thus knows better when and how to chmod()/chown() it back. */
5790 if (!exec_context_may_touch_tty(c))
5791 return;
5792
5793 path = exec_context_tty_path(c);
5794 if (!path)
5795 return;
5796
5797 fd = open(path, O_PATH|O_CLOEXEC);
5798 if (fd < 0)
5799 return (void) log_full_errno(errno == ENOENT ? LOG_DEBUG : LOG_WARNING, errno,
5800 "Failed to open TTY inode of '%s' to adjust ownership/access mode, ignoring: %m",
5801 path);
5802
5803 if (fstat(fd, &st) < 0)
5804 return (void) log_warning_errno(errno, "Failed to stat TTY '%s', ignoring: %m", path);
5805
5806 /* Let's add a superficial check that we only do this for stuff that looks like a TTY. We only check
5807 * if things are a character device, since a proper check either means we'd have to open the TTY and
5808 * use isatty(), but we'd rather not do that since opening TTYs comes with all kinds of side-effects
5809 * and is slow. Or we'd have to hardcode dev_t major information, which we'd rather avoid. Why bother
5810 * with this at all? → https://github.com/systemd/systemd/issues/19213 */
5811 if (!S_ISCHR(st.st_mode))
5812 return log_warning("Configured TTY '%s' is not actually a character device, ignoring.", path);
5813
5814 r = fchmod_and_chown(fd, TTY_MODE, 0, TTY_GID);
5815 if (r < 0)
5816 log_warning_errno(r, "Failed to reset TTY ownership/access mode of %s, ignoring: %m", path);
5817 }
5818
5819 int exec_context_get_clean_directories(
5820 ExecContext *c,
5821 char **prefix,
5822 ExecCleanMask mask,
5823 char ***ret) {
5824
5825 _cleanup_strv_free_ char **l = NULL;
5826 int r;
5827
5828 assert(c);
5829 assert(prefix);
5830 assert(ret);
5831
5832 for (ExecDirectoryType t = 0; t < _EXEC_DIRECTORY_TYPE_MAX; t++) {
5833 char **i;
5834
5835 if (!FLAGS_SET(mask, 1U << t))
5836 continue;
5837
5838 if (!prefix[t])
5839 continue;
5840
5841 STRV_FOREACH(i, c->directories[t].paths) {
5842 char *j;
5843
5844 j = path_join(prefix[t], *i);
5845 if (!j)
5846 return -ENOMEM;
5847
5848 r = strv_consume(&l, j);
5849 if (r < 0)
5850 return r;
5851
5852 /* Also remove private directories unconditionally. */
5853 if (t != EXEC_DIRECTORY_CONFIGURATION) {
5854 j = path_join(prefix[t], "private", *i);
5855 if (!j)
5856 return -ENOMEM;
5857
5858 r = strv_consume(&l, j);
5859 if (r < 0)
5860 return r;
5861 }
5862 }
5863 }
5864
5865 *ret = TAKE_PTR(l);
5866 return 0;
5867 }
5868
5869 int exec_context_get_clean_mask(ExecContext *c, ExecCleanMask *ret) {
5870 ExecCleanMask mask = 0;
5871
5872 assert(c);
5873 assert(ret);
5874
5875 for (ExecDirectoryType t = 0; t < _EXEC_DIRECTORY_TYPE_MAX; t++)
5876 if (!strv_isempty(c->directories[t].paths))
5877 mask |= 1U << t;
5878
5879 *ret = mask;
5880 return 0;
5881 }
5882
5883 void exec_status_start(ExecStatus *s, pid_t pid) {
5884 assert(s);
5885
5886 *s = (ExecStatus) {
5887 .pid = pid,
5888 };
5889
5890 dual_timestamp_get(&s->start_timestamp);
5891 }
5892
5893 void exec_status_exit(ExecStatus *s, const ExecContext *context, pid_t pid, int code, int status) {
5894 assert(s);
5895
5896 if (s->pid != pid)
5897 *s = (ExecStatus) {
5898 .pid = pid,
5899 };
5900
5901 dual_timestamp_get(&s->exit_timestamp);
5902
5903 s->code = code;
5904 s->status = status;
5905
5906 if (context && context->utmp_id)
5907 (void) utmp_put_dead_process(context->utmp_id, pid, code, status);
5908 }
5909
5910 void exec_status_reset(ExecStatus *s) {
5911 assert(s);
5912
5913 *s = (ExecStatus) {};
5914 }
5915
5916 void exec_status_dump(const ExecStatus *s, FILE *f, const char *prefix) {
5917 char buf[FORMAT_TIMESTAMP_MAX];
5918
5919 assert(s);
5920 assert(f);
5921
5922 if (s->pid <= 0)
5923 return;
5924
5925 prefix = strempty(prefix);
5926
5927 fprintf(f,
5928 "%sPID: "PID_FMT"\n",
5929 prefix, s->pid);
5930
5931 if (dual_timestamp_is_set(&s->start_timestamp))
5932 fprintf(f,
5933 "%sStart Timestamp: %s\n",
5934 prefix, format_timestamp(buf, sizeof(buf), s->start_timestamp.realtime));
5935
5936 if (dual_timestamp_is_set(&s->exit_timestamp))
5937 fprintf(f,
5938 "%sExit Timestamp: %s\n"
5939 "%sExit Code: %s\n"
5940 "%sExit Status: %i\n",
5941 prefix, format_timestamp(buf, sizeof(buf), s->exit_timestamp.realtime),
5942 prefix, sigchld_code_to_string(s->code),
5943 prefix, s->status);
5944 }
5945
5946 static char *exec_command_line(char **argv) {
5947 size_t k;
5948 char *n, *p, **a;
5949 bool first = true;
5950
5951 assert(argv);
5952
5953 k = 1;
5954 STRV_FOREACH(a, argv)
5955 k += strlen(*a)+3;
5956
5957 n = new(char, k);
5958 if (!n)
5959 return NULL;
5960
5961 p = n;
5962 STRV_FOREACH(a, argv) {
5963
5964 if (!first)
5965 *(p++) = ' ';
5966 else
5967 first = false;
5968
5969 if (strpbrk(*a, WHITESPACE)) {
5970 *(p++) = '\'';
5971 p = stpcpy(p, *a);
5972 *(p++) = '\'';
5973 } else
5974 p = stpcpy(p, *a);
5975
5976 }
5977
5978 *p = 0;
5979
5980 /* FIXME: this doesn't really handle arguments that have
5981 * spaces and ticks in them */
5982
5983 return n;
5984 }
5985
5986 static void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
5987 _cleanup_free_ char *cmd = NULL;
5988 const char *prefix2;
5989
5990 assert(c);
5991 assert(f);
5992
5993 prefix = strempty(prefix);
5994 prefix2 = strjoina(prefix, "\t");
5995
5996 cmd = exec_command_line(c->argv);
5997 fprintf(f,
5998 "%sCommand Line: %s\n",
5999 prefix, cmd ? cmd : strerror_safe(ENOMEM));
6000
6001 exec_status_dump(&c->exec_status, f, prefix2);
6002 }
6003
6004 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {
6005 assert(f);
6006
6007 prefix = strempty(prefix);
6008
6009 LIST_FOREACH(command, c, c)
6010 exec_command_dump(c, f, prefix);
6011 }
6012
6013 void exec_command_append_list(ExecCommand **l, ExecCommand *e) {
6014 ExecCommand *end;
6015
6016 assert(l);
6017 assert(e);
6018
6019 if (*l) {
6020 /* It's kind of important, that we keep the order here */
6021 LIST_FIND_TAIL(command, *l, end);
6022 LIST_INSERT_AFTER(command, *l, end, e);
6023 } else
6024 *l = e;
6025 }
6026
6027 int exec_command_set(ExecCommand *c, const char *path, ...) {
6028 va_list ap;
6029 char **l, *p;
6030
6031 assert(c);
6032 assert(path);
6033
6034 va_start(ap, path);
6035 l = strv_new_ap(path, ap);
6036 va_end(ap);
6037
6038 if (!l)
6039 return -ENOMEM;
6040
6041 p = strdup(path);
6042 if (!p) {
6043 strv_free(l);
6044 return -ENOMEM;
6045 }
6046
6047 free_and_replace(c->path, p);
6048
6049 return strv_free_and_replace(c->argv, l);
6050 }
6051
6052 int exec_command_append(ExecCommand *c, const char *path, ...) {
6053 _cleanup_strv_free_ char **l = NULL;
6054 va_list ap;
6055 int r;
6056
6057 assert(c);
6058 assert(path);
6059
6060 va_start(ap, path);
6061 l = strv_new_ap(path, ap);
6062 va_end(ap);
6063
6064 if (!l)
6065 return -ENOMEM;
6066
6067 r = strv_extend_strv(&c->argv, l, false);
6068 if (r < 0)
6069 return r;
6070
6071 return 0;
6072 }
6073
6074 static void *remove_tmpdir_thread(void *p) {
6075 _cleanup_free_ char *path = p;
6076
6077 (void) rm_rf(path, REMOVE_ROOT|REMOVE_PHYSICAL);
6078 return NULL;
6079 }
6080
6081 static ExecRuntime* exec_runtime_free(ExecRuntime *rt, bool destroy) {
6082 int r;
6083
6084 if (!rt)
6085 return NULL;
6086
6087 if (rt->manager)
6088 (void) hashmap_remove(rt->manager->exec_runtime_by_id, rt->id);
6089
6090 /* When destroy is true, then rm_rf tmp_dir and var_tmp_dir. */
6091
6092 if (destroy && rt->tmp_dir && !streq(rt->tmp_dir, RUN_SYSTEMD_EMPTY)) {
6093 log_debug("Spawning thread to nuke %s", rt->tmp_dir);
6094
6095 r = asynchronous_job(remove_tmpdir_thread, rt->tmp_dir);
6096 if (r < 0)
6097 log_warning_errno(r, "Failed to nuke %s: %m", rt->tmp_dir);
6098 else
6099 rt->tmp_dir = NULL;
6100 }
6101
6102 if (destroy && rt->var_tmp_dir && !streq(rt->var_tmp_dir, RUN_SYSTEMD_EMPTY)) {
6103 log_debug("Spawning thread to nuke %s", rt->var_tmp_dir);
6104
6105 r = asynchronous_job(remove_tmpdir_thread, rt->var_tmp_dir);
6106 if (r < 0)
6107 log_warning_errno(r, "Failed to nuke %s: %m", rt->var_tmp_dir);
6108 else
6109 rt->var_tmp_dir = NULL;
6110 }
6111
6112 rt->id = mfree(rt->id);
6113 rt->tmp_dir = mfree(rt->tmp_dir);
6114 rt->var_tmp_dir = mfree(rt->var_tmp_dir);
6115 safe_close_pair(rt->netns_storage_socket);
6116 safe_close_pair(rt->ipcns_storage_socket);
6117 return mfree(rt);
6118 }
6119
6120 static void exec_runtime_freep(ExecRuntime **rt) {
6121 (void) exec_runtime_free(*rt, false);
6122 }
6123
6124 static int exec_runtime_allocate(ExecRuntime **ret, const char *id) {
6125 _cleanup_free_ char *id_copy = NULL;
6126 ExecRuntime *n;
6127
6128 assert(ret);
6129
6130 id_copy = strdup(id);
6131 if (!id_copy)
6132 return -ENOMEM;
6133
6134 n = new(ExecRuntime, 1);
6135 if (!n)
6136 return -ENOMEM;
6137
6138 *n = (ExecRuntime) {
6139 .id = TAKE_PTR(id_copy),
6140 .netns_storage_socket = { -1, -1 },
6141 .ipcns_storage_socket = { -1, -1 },
6142 };
6143
6144 *ret = n;
6145 return 0;
6146 }
6147
6148 static int exec_runtime_add(
6149 Manager *m,
6150 const char *id,
6151 char **tmp_dir,
6152 char **var_tmp_dir,
6153 int netns_storage_socket[2],
6154 int ipcns_storage_socket[2],
6155 ExecRuntime **ret) {
6156
6157 _cleanup_(exec_runtime_freep) ExecRuntime *rt = NULL;
6158 int r;
6159
6160 assert(m);
6161 assert(id);
6162
6163 /* tmp_dir, var_tmp_dir, {net,ipc}ns_storage_socket fds are donated on success */
6164
6165 r = exec_runtime_allocate(&rt, id);
6166 if (r < 0)
6167 return r;
6168
6169 r = hashmap_ensure_put(&m->exec_runtime_by_id, &string_hash_ops, rt->id, rt);
6170 if (r < 0)
6171 return r;
6172
6173 assert(!!rt->tmp_dir == !!rt->var_tmp_dir); /* We require both to be set together */
6174 rt->tmp_dir = TAKE_PTR(*tmp_dir);
6175 rt->var_tmp_dir = TAKE_PTR(*var_tmp_dir);
6176
6177 if (netns_storage_socket) {
6178 rt->netns_storage_socket[0] = TAKE_FD(netns_storage_socket[0]);
6179 rt->netns_storage_socket[1] = TAKE_FD(netns_storage_socket[1]);
6180 }
6181
6182 if (ipcns_storage_socket) {
6183 rt->ipcns_storage_socket[0] = TAKE_FD(ipcns_storage_socket[0]);
6184 rt->ipcns_storage_socket[1] = TAKE_FD(ipcns_storage_socket[1]);
6185 }
6186
6187 rt->manager = m;
6188
6189 if (ret)
6190 *ret = rt;
6191 /* do not remove created ExecRuntime object when the operation succeeds. */
6192 TAKE_PTR(rt);
6193 return 0;
6194 }
6195
6196 static int exec_runtime_make(
6197 Manager *m,
6198 const ExecContext *c,
6199 const char *id,
6200 ExecRuntime **ret) {
6201
6202 _cleanup_(namespace_cleanup_tmpdirp) char *tmp_dir = NULL, *var_tmp_dir = NULL;
6203 _cleanup_close_pair_ int netns_storage_socket[2] = { -1, -1 }, ipcns_storage_socket[2] = { -1, -1 };
6204 int r;
6205
6206 assert(m);
6207 assert(c);
6208 assert(id);
6209
6210 /* It is not necessary to create ExecRuntime object. */
6211 if (!c->private_network && !c->private_ipc && !c->private_tmp && !c->network_namespace_path) {
6212 *ret = NULL;
6213 return 0;
6214 }
6215
6216 if (c->private_tmp &&
6217 !(prefixed_path_strv_contains(c->inaccessible_paths, "/tmp") &&
6218 (prefixed_path_strv_contains(c->inaccessible_paths, "/var/tmp") ||
6219 prefixed_path_strv_contains(c->inaccessible_paths, "/var")))) {
6220 r = setup_tmp_dirs(id, &tmp_dir, &var_tmp_dir);
6221 if (r < 0)
6222 return r;
6223 }
6224
6225 if (c->private_network || c->network_namespace_path) {
6226 if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0, netns_storage_socket) < 0)
6227 return -errno;
6228 }
6229
6230 if (c->private_ipc || c->ipc_namespace_path) {
6231 if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0, ipcns_storage_socket) < 0)
6232 return -errno;
6233 }
6234
6235 r = exec_runtime_add(m, id, &tmp_dir, &var_tmp_dir, netns_storage_socket, ipcns_storage_socket, ret);
6236 if (r < 0)
6237 return r;
6238
6239 return 1;
6240 }
6241
6242 int exec_runtime_acquire(Manager *m, const ExecContext *c, const char *id, bool create, ExecRuntime **ret) {
6243 ExecRuntime *rt;
6244 int r;
6245
6246 assert(m);
6247 assert(id);
6248 assert(ret);
6249
6250 rt = hashmap_get(m->exec_runtime_by_id, id);
6251 if (rt)
6252 /* We already have a ExecRuntime object, let's increase the ref count and reuse it */
6253 goto ref;
6254
6255 if (!create) {
6256 *ret = NULL;
6257 return 0;
6258 }
6259
6260 /* If not found, then create a new object. */
6261 r = exec_runtime_make(m, c, id, &rt);
6262 if (r < 0)
6263 return r;
6264 if (r == 0) {
6265 /* When r == 0, it is not necessary to create ExecRuntime object. */
6266 *ret = NULL;
6267 return 0;
6268 }
6269
6270 ref:
6271 /* increment reference counter. */
6272 rt->n_ref++;
6273 *ret = rt;
6274 return 1;
6275 }
6276
6277 ExecRuntime *exec_runtime_unref(ExecRuntime *rt, bool destroy) {
6278 if (!rt)
6279 return NULL;
6280
6281 assert(rt->n_ref > 0);
6282
6283 rt->n_ref--;
6284 if (rt->n_ref > 0)
6285 return NULL;
6286
6287 return exec_runtime_free(rt, destroy);
6288 }
6289
6290 int exec_runtime_serialize(const Manager *m, FILE *f, FDSet *fds) {
6291 ExecRuntime *rt;
6292
6293 assert(m);
6294 assert(f);
6295 assert(fds);
6296
6297 HASHMAP_FOREACH(rt, m->exec_runtime_by_id) {
6298 fprintf(f, "exec-runtime=%s", rt->id);
6299
6300 if (rt->tmp_dir)
6301 fprintf(f, " tmp-dir=%s", rt->tmp_dir);
6302
6303 if (rt->var_tmp_dir)
6304 fprintf(f, " var-tmp-dir=%s", rt->var_tmp_dir);
6305
6306 if (rt->netns_storage_socket[0] >= 0) {
6307 int copy;
6308
6309 copy = fdset_put_dup(fds, rt->netns_storage_socket[0]);
6310 if (copy < 0)
6311 return copy;
6312
6313 fprintf(f, " netns-socket-0=%i", copy);
6314 }
6315
6316 if (rt->netns_storage_socket[1] >= 0) {
6317 int copy;
6318
6319 copy = fdset_put_dup(fds, rt->netns_storage_socket[1]);
6320 if (copy < 0)
6321 return copy;
6322
6323 fprintf(f, " netns-socket-1=%i", copy);
6324 }
6325
6326 if (rt->ipcns_storage_socket[0] >= 0) {
6327 int copy;
6328
6329 copy = fdset_put_dup(fds, rt->ipcns_storage_socket[0]);
6330 if (copy < 0)
6331 return copy;
6332
6333 fprintf(f, " ipcns-socket-0=%i", copy);
6334 }
6335
6336 if (rt->ipcns_storage_socket[1] >= 0) {
6337 int copy;
6338
6339 copy = fdset_put_dup(fds, rt->ipcns_storage_socket[1]);
6340 if (copy < 0)
6341 return copy;
6342
6343 fprintf(f, " ipcns-socket-1=%i", copy);
6344 }
6345
6346 fputc('\n', f);
6347 }
6348
6349 return 0;
6350 }
6351
6352 int exec_runtime_deserialize_compat(Unit *u, const char *key, const char *value, FDSet *fds) {
6353 _cleanup_(exec_runtime_freep) ExecRuntime *rt_create = NULL;
6354 ExecRuntime *rt;
6355 int r;
6356
6357 /* This is for the migration from old (v237 or earlier) deserialization text.
6358 * Due to the bug #7790, this may not work with the units that use JoinsNamespaceOf=.
6359 * Even if the ExecRuntime object originally created by the other unit, we cannot judge
6360 * so or not from the serialized text, then we always creates a new object owned by this. */
6361
6362 assert(u);
6363 assert(key);
6364 assert(value);
6365
6366 /* Manager manages ExecRuntime objects by the unit id.
6367 * So, we omit the serialized text when the unit does not have id (yet?)... */
6368 if (isempty(u->id)) {
6369 log_unit_debug(u, "Invocation ID not found. Dropping runtime parameter.");
6370 return 0;
6371 }
6372
6373 if (hashmap_ensure_allocated(&u->manager->exec_runtime_by_id, &string_hash_ops) < 0)
6374 return log_oom();
6375
6376 rt = hashmap_get(u->manager->exec_runtime_by_id, u->id);
6377 if (!rt) {
6378 if (exec_runtime_allocate(&rt_create, u->id) < 0)
6379 return log_oom();
6380
6381 rt = rt_create;
6382 }
6383
6384 if (streq(key, "tmp-dir")) {
6385 if (free_and_strdup_warn(&rt->tmp_dir, value) < 0)
6386 return -ENOMEM;
6387
6388 } else if (streq(key, "var-tmp-dir")) {
6389 if (free_and_strdup_warn(&rt->var_tmp_dir, value) < 0)
6390 return -ENOMEM;
6391
6392 } else if (streq(key, "netns-socket-0")) {
6393 int fd;
6394
6395 if (safe_atoi(value, &fd) < 0 || !fdset_contains(fds, fd)) {
6396 log_unit_debug(u, "Failed to parse netns socket value: %s", value);
6397 return 0;
6398 }
6399
6400 safe_close(rt->netns_storage_socket[0]);
6401 rt->netns_storage_socket[0] = fdset_remove(fds, fd);
6402
6403 } else if (streq(key, "netns-socket-1")) {
6404 int fd;
6405
6406 if (safe_atoi(value, &fd) < 0 || !fdset_contains(fds, fd)) {
6407 log_unit_debug(u, "Failed to parse netns socket value: %s", value);
6408 return 0;
6409 }
6410
6411 safe_close(rt->netns_storage_socket[1]);
6412 rt->netns_storage_socket[1] = fdset_remove(fds, fd);
6413
6414 } else
6415 return 0;
6416
6417 /* If the object is newly created, then put it to the hashmap which manages ExecRuntime objects. */
6418 if (rt_create) {
6419 r = hashmap_put(u->manager->exec_runtime_by_id, rt_create->id, rt_create);
6420 if (r < 0) {
6421 log_unit_debug_errno(u, r, "Failed to put runtime parameter to manager's storage: %m");
6422 return 0;
6423 }
6424
6425 rt_create->manager = u->manager;
6426
6427 /* Avoid cleanup */
6428 TAKE_PTR(rt_create);
6429 }
6430
6431 return 1;
6432 }
6433
6434 int exec_runtime_deserialize_one(Manager *m, const char *value, FDSet *fds) {
6435 _cleanup_free_ char *tmp_dir = NULL, *var_tmp_dir = NULL;
6436 char *id = NULL;
6437 int r, netns_fdpair[] = {-1, -1}, ipcns_fdpair[] = {-1, -1};
6438 const char *p, *v = value;
6439 size_t n;
6440
6441 assert(m);
6442 assert(value);
6443 assert(fds);
6444
6445 n = strcspn(v, " ");
6446 id = strndupa(v, n);
6447 if (v[n] != ' ')
6448 goto finalize;
6449 p = v + n + 1;
6450
6451 v = startswith(p, "tmp-dir=");
6452 if (v) {
6453 n = strcspn(v, " ");
6454 tmp_dir = strndup(v, n);
6455 if (!tmp_dir)
6456 return log_oom();
6457 if (v[n] != ' ')
6458 goto finalize;
6459 p = v + n + 1;
6460 }
6461
6462 v = startswith(p, "var-tmp-dir=");
6463 if (v) {
6464 n = strcspn(v, " ");
6465 var_tmp_dir = strndup(v, n);
6466 if (!var_tmp_dir)
6467 return log_oom();
6468 if (v[n] != ' ')
6469 goto finalize;
6470 p = v + n + 1;
6471 }
6472
6473 v = startswith(p, "netns-socket-0=");
6474 if (v) {
6475 char *buf;
6476
6477 n = strcspn(v, " ");
6478 buf = strndupa(v, n);
6479
6480 r = safe_atoi(buf, &netns_fdpair[0]);
6481 if (r < 0)
6482 return log_debug_errno(r, "Unable to parse exec-runtime specification netns-socket-0=%s: %m", buf);
6483 if (!fdset_contains(fds, netns_fdpair[0]))
6484 return log_debug_errno(SYNTHETIC_ERRNO(EBADF),
6485 "exec-runtime specification netns-socket-0= refers to unknown fd %d: %m", netns_fdpair[0]);
6486 netns_fdpair[0] = fdset_remove(fds, netns_fdpair[0]);
6487 if (v[n] != ' ')
6488 goto finalize;
6489 p = v + n + 1;
6490 }
6491
6492 v = startswith(p, "netns-socket-1=");
6493 if (v) {
6494 char *buf;
6495
6496 n = strcspn(v, " ");
6497 buf = strndupa(v, n);
6498
6499 r = safe_atoi(buf, &netns_fdpair[1]);
6500 if (r < 0)
6501 return log_debug_errno(r, "Unable to parse exec-runtime specification netns-socket-1=%s: %m", buf);
6502 if (!fdset_contains(fds, netns_fdpair[1]))
6503 return log_debug_errno(SYNTHETIC_ERRNO(EBADF),
6504 "exec-runtime specification netns-socket-1= refers to unknown fd %d: %m", netns_fdpair[1]);
6505 netns_fdpair[1] = fdset_remove(fds, netns_fdpair[1]);
6506 if (v[n] != ' ')
6507 goto finalize;
6508 p = v + n + 1;
6509 }
6510
6511 v = startswith(p, "ipcns-socket-0=");
6512 if (v) {
6513 char *buf;
6514
6515 n = strcspn(v, " ");
6516 buf = strndupa(v, n);
6517
6518 r = safe_atoi(buf, &ipcns_fdpair[0]);
6519 if (r < 0)
6520 return log_debug_errno(r, "Unable to parse exec-runtime specification ipcns-socket-0=%s: %m", buf);
6521 if (!fdset_contains(fds, ipcns_fdpair[0]))
6522 return log_debug_errno(SYNTHETIC_ERRNO(EBADF),
6523 "exec-runtime specification ipcns-socket-0= refers to unknown fd %d: %m", ipcns_fdpair[0]);
6524 ipcns_fdpair[0] = fdset_remove(fds, ipcns_fdpair[0]);
6525 if (v[n] != ' ')
6526 goto finalize;
6527 p = v + n + 1;
6528 }
6529
6530 v = startswith(p, "ipcns-socket-1=");
6531 if (v) {
6532 char *buf;
6533
6534 n = strcspn(v, " ");
6535 buf = strndupa(v, n);
6536
6537 r = safe_atoi(buf, &ipcns_fdpair[1]);
6538 if (r < 0)
6539 return log_debug_errno(r, "Unable to parse exec-runtime specification ipcns-socket-1=%s: %m", buf);
6540 if (!fdset_contains(fds, ipcns_fdpair[1]))
6541 return log_debug_errno(SYNTHETIC_ERRNO(EBADF),
6542 "exec-runtime specification ipcns-socket-1= refers to unknown fd %d: %m", ipcns_fdpair[1]);
6543 ipcns_fdpair[1] = fdset_remove(fds, ipcns_fdpair[1]);
6544 }
6545
6546 finalize:
6547 r = exec_runtime_add(m, id, &tmp_dir, &var_tmp_dir, netns_fdpair, ipcns_fdpair, NULL);
6548 if (r < 0)
6549 return log_debug_errno(r, "Failed to add exec-runtime: %m");
6550 return 0;
6551 }
6552
6553 void exec_runtime_vacuum(Manager *m) {
6554 ExecRuntime *rt;
6555
6556 assert(m);
6557
6558 /* Free unreferenced ExecRuntime objects. This is used after manager deserialization process. */
6559
6560 HASHMAP_FOREACH(rt, m->exec_runtime_by_id) {
6561 if (rt->n_ref > 0)
6562 continue;
6563
6564 (void) exec_runtime_free(rt, false);
6565 }
6566 }
6567
6568 void exec_params_clear(ExecParameters *p) {
6569 if (!p)
6570 return;
6571
6572 p->environment = strv_free(p->environment);
6573 p->fd_names = strv_free(p->fd_names);
6574 p->fds = mfree(p->fds);
6575 p->exec_fd = safe_close(p->exec_fd);
6576 }
6577
6578 ExecSetCredential *exec_set_credential_free(ExecSetCredential *sc) {
6579 if (!sc)
6580 return NULL;
6581
6582 free(sc->id);
6583 free(sc->data);
6584 return mfree(sc);
6585 }
6586
6587 DEFINE_HASH_OPS_WITH_VALUE_DESTRUCTOR(exec_set_credential_hash_ops, char, string_hash_func, string_compare_func, ExecSetCredential, exec_set_credential_free);
6588
6589 static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
6590 [EXEC_INPUT_NULL] = "null",
6591 [EXEC_INPUT_TTY] = "tty",
6592 [EXEC_INPUT_TTY_FORCE] = "tty-force",
6593 [EXEC_INPUT_TTY_FAIL] = "tty-fail",
6594 [EXEC_INPUT_SOCKET] = "socket",
6595 [EXEC_INPUT_NAMED_FD] = "fd",
6596 [EXEC_INPUT_DATA] = "data",
6597 [EXEC_INPUT_FILE] = "file",
6598 };
6599
6600 DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput);
6601
6602 static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
6603 [EXEC_OUTPUT_INHERIT] = "inherit",
6604 [EXEC_OUTPUT_NULL] = "null",
6605 [EXEC_OUTPUT_TTY] = "tty",
6606 [EXEC_OUTPUT_KMSG] = "kmsg",
6607 [EXEC_OUTPUT_KMSG_AND_CONSOLE] = "kmsg+console",
6608 [EXEC_OUTPUT_JOURNAL] = "journal",
6609 [EXEC_OUTPUT_JOURNAL_AND_CONSOLE] = "journal+console",
6610 [EXEC_OUTPUT_SOCKET] = "socket",
6611 [EXEC_OUTPUT_NAMED_FD] = "fd",
6612 [EXEC_OUTPUT_FILE] = "file",
6613 [EXEC_OUTPUT_FILE_APPEND] = "append",
6614 [EXEC_OUTPUT_FILE_TRUNCATE] = "truncate",
6615 };
6616
6617 DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);
6618
6619 static const char* const exec_utmp_mode_table[_EXEC_UTMP_MODE_MAX] = {
6620 [EXEC_UTMP_INIT] = "init",
6621 [EXEC_UTMP_LOGIN] = "login",
6622 [EXEC_UTMP_USER] = "user",
6623 };
6624
6625 DEFINE_STRING_TABLE_LOOKUP(exec_utmp_mode, ExecUtmpMode);
6626
6627 static const char* const exec_preserve_mode_table[_EXEC_PRESERVE_MODE_MAX] = {
6628 [EXEC_PRESERVE_NO] = "no",
6629 [EXEC_PRESERVE_YES] = "yes",
6630 [EXEC_PRESERVE_RESTART] = "restart",
6631 };
6632
6633 DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(exec_preserve_mode, ExecPreserveMode, EXEC_PRESERVE_YES);
6634
6635 /* This table maps ExecDirectoryType to the setting it is configured with in the unit */
6636 static const char* const exec_directory_type_table[_EXEC_DIRECTORY_TYPE_MAX] = {
6637 [EXEC_DIRECTORY_RUNTIME] = "RuntimeDirectory",
6638 [EXEC_DIRECTORY_STATE] = "StateDirectory",
6639 [EXEC_DIRECTORY_CACHE] = "CacheDirectory",
6640 [EXEC_DIRECTORY_LOGS] = "LogsDirectory",
6641 [EXEC_DIRECTORY_CONFIGURATION] = "ConfigurationDirectory",
6642 };
6643
6644 DEFINE_STRING_TABLE_LOOKUP(exec_directory_type, ExecDirectoryType);
6645
6646 /* And this table maps ExecDirectoryType too, but to a generic term identifying the type of resource. This
6647 * one is supposed to be generic enough to be used for unit types that don't use ExecContext and per-unit
6648 * directories, specifically .timer units with their timestamp touch file. */
6649 static const char* const exec_resource_type_table[_EXEC_DIRECTORY_TYPE_MAX] = {
6650 [EXEC_DIRECTORY_RUNTIME] = "runtime",
6651 [EXEC_DIRECTORY_STATE] = "state",
6652 [EXEC_DIRECTORY_CACHE] = "cache",
6653 [EXEC_DIRECTORY_LOGS] = "logs",
6654 [EXEC_DIRECTORY_CONFIGURATION] = "configuration",
6655 };
6656
6657 DEFINE_STRING_TABLE_LOOKUP(exec_resource_type, ExecDirectoryType);
6658
6659 /* And this table also maps ExecDirectoryType, to the environment variable we pass the selected directory to
6660 * the service payload in. */
6661 static const char* const exec_directory_env_name_table[_EXEC_DIRECTORY_TYPE_MAX] = {
6662 [EXEC_DIRECTORY_RUNTIME] = "RUNTIME_DIRECTORY",
6663 [EXEC_DIRECTORY_STATE] = "STATE_DIRECTORY",
6664 [EXEC_DIRECTORY_CACHE] = "CACHE_DIRECTORY",
6665 [EXEC_DIRECTORY_LOGS] = "LOGS_DIRECTORY",
6666 [EXEC_DIRECTORY_CONFIGURATION] = "CONFIGURATION_DIRECTORY",
6667 };
6668
6669 DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(exec_directory_env_name, ExecDirectoryType);
6670
6671 static const char* const exec_keyring_mode_table[_EXEC_KEYRING_MODE_MAX] = {
6672 [EXEC_KEYRING_INHERIT] = "inherit",
6673 [EXEC_KEYRING_PRIVATE] = "private",
6674 [EXEC_KEYRING_SHARED] = "shared",
6675 };
6676
6677 DEFINE_STRING_TABLE_LOOKUP(exec_keyring_mode, ExecKeyringMode);
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