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Merge pull request #2384 from 2xsec/bugfix
[mirror_lxc.git] / src / lxc / lxccontainer.c
1 /* liblxcapi
2 *
3 * Copyright © 2012 Serge Hallyn <serge.hallyn@ubuntu.com>.
4 * Copyright © 2012 Canonical Ltd.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #define _GNU_SOURCE
22 #include <arpa/inet.h>
23 #include <dirent.h>
24 #include <errno.h>
25 #include <fcntl.h>
26 #include <grp.h>
27 #include <libgen.h>
28 #include <pthread.h>
29 #include <sched.h>
30 #include <stdarg.h>
31 #include <stdint.h>
32 #include <stdio.h>
33 #include <sys/file.h>
34 #include <sys/mman.h>
35 #include <sys/mount.h>
36 #include <sys/syscall.h>
37 #include <sys/sysmacros.h>
38 #include <sys/types.h>
39 #include <sys/wait.h>
40 #include <unistd.h>
41
42 #include "af_unix.h"
43 #include "attach.h"
44 #include "cgroup.h"
45 #include "commands.h"
46 #include "commands_utils.h"
47 #include "conf.h"
48 #include "config.h"
49 #include "confile.h"
50 #include "confile_utils.h"
51 #include "criu.h"
52 #include "error.h"
53 #include "initutils.h"
54 #include "log.h"
55 #include "lxc.h"
56 #include "lxccontainer.h"
57 #include "lxclock.h"
58 #include "monitor.h"
59 #include "namespace.h"
60 #include "network.h"
61 #include "parse.h"
62 #include "start.h"
63 #include "state.h"
64 #include "storage.h"
65 #include "storage/btrfs.h"
66 #include "storage/overlay.h"
67 #include "storage_utils.h"
68 #include "sync.h"
69 #include "terminal.h"
70 #include "utils.h"
71 #include "version.h"
72
73 /* major()/minor() */
74 #ifdef MAJOR_IN_MKDEV
75 #include <sys/mkdev.h>
76 #endif
77
78 #if HAVE_IFADDRS_H
79 #include <ifaddrs.h>
80 #else
81 #include <../include/ifaddrs.h>
82 #endif
83
84 #if IS_BIONIC
85 #include <../include/lxcmntent.h>
86 #else
87 #include <mntent.h>
88 #endif
89
90 #ifndef HAVE_STRLCPY
91 #include "include/strlcpy.h"
92 #endif
93
94 /* Define faccessat() if missing from the C library */
95 #ifndef HAVE_FACCESSAT
96 static int faccessat(int __fd, const char *__file, int __type, int __flag)
97 {
98 #ifdef __NR_faccessat
99 return syscall(__NR_faccessat, __fd, __file, __type, __flag);
100 #else
101 errno = ENOSYS;
102 return -1;
103 #endif
104 }
105 #endif
106
107 lxc_log_define(lxc_container, lxc);
108
109 static bool do_lxcapi_destroy(struct lxc_container *c);
110 static const char *lxcapi_get_config_path(struct lxc_container *c);
111 #define do_lxcapi_get_config_path(c) lxcapi_get_config_path(c)
112 static bool do_lxcapi_set_config_item(struct lxc_container *c, const char *key, const char *v);
113 static bool container_destroy(struct lxc_container *c,
114 struct lxc_storage *storage);
115 static bool get_snappath_dir(struct lxc_container *c, char *snappath);
116 static bool lxcapi_snapshot_destroy_all(struct lxc_container *c);
117 static bool do_lxcapi_save_config(struct lxc_container *c, const char *alt_file);
118
119 static bool config_file_exists(const char *lxcpath, const char *cname)
120 {
121 int ret;
122 size_t len;
123 char *fname;
124
125 /* $lxcpath + '/' + $cname + '/config' + \0 */
126 len = strlen(lxcpath) + strlen(cname) + 9;
127 fname = alloca(len);
128 ret = snprintf(fname, len, "%s/%s/config", lxcpath, cname);
129 if (ret < 0 || (size_t)ret >= len)
130 return false;
131
132 return file_exists(fname);
133 }
134
135 /* A few functions to help detect when a container creation failed. If a
136 * container creation was killed partway through, then trying to actually start
137 * that container could harm the host. We detect this by creating a 'partial'
138 * file under the container directory, and keeping an advisory lock. When
139 * container creation completes, we remove that file. When we load or try to
140 * start a container, if we find that file, without a flock, we remove the
141 * container.
142 */
143 static int ongoing_create(struct lxc_container *c)
144 {
145 int fd, ret;
146 size_t len;
147 char *path;
148 struct flock lk = {0};
149
150 len = strlen(c->config_path) + strlen(c->name) + 10;
151 path = alloca(len);
152 ret = snprintf(path, len, "%s/%s/partial", c->config_path, c->name);
153 if (ret < 0 || (size_t)ret >= len)
154 return -1;
155
156 if (!file_exists(path))
157 return 0;
158
159 fd = open(path, O_RDWR);
160 if (fd < 0)
161 return 0;
162
163 lk.l_type = F_WRLCK;
164 lk.l_whence = SEEK_SET;
165 lk.l_pid = -1;
166
167 ret = fcntl(fd, F_OFD_GETLK, &lk);
168 if (ret < 0 && errno == EINVAL)
169 ret = flock(fd, LOCK_EX | LOCK_NB);
170 close(fd);
171 if (ret == 0 && lk.l_pid != -1) {
172 /* create is still ongoing */
173 return 1;
174 }
175
176 /* Create completed but partial is still there. */
177 return 2;
178 }
179
180 static int create_partial(struct lxc_container *c)
181 {
182 int fd, ret;
183 size_t len;
184 char *path;
185 struct flock lk = {0};
186
187 /* $lxcpath + '/' + $name + '/partial' + \0 */
188 len = strlen(c->config_path) + strlen(c->name) + 10;
189 path = alloca(len);
190 ret = snprintf(path, len, "%s/%s/partial", c->config_path, c->name);
191 if (ret < 0 || (size_t)ret >= len)
192 return -1;
193
194 fd = open(path, O_RDWR | O_CREAT | O_EXCL, 0755);
195 if (fd < 0)
196 return -1;
197
198 lk.l_type = F_WRLCK;
199 lk.l_whence = SEEK_SET;
200
201 ret = fcntl(fd, F_OFD_SETLKW, &lk);
202 if (ret < 0) {
203 if (errno == EINVAL) {
204 ret = flock(fd, LOCK_EX);
205 if (ret == 0)
206 return fd;
207 }
208
209 SYSERROR("Failed to lock partial file %s", path);
210 close(fd);
211 return -1;
212 }
213
214 return fd;
215 }
216
217 static void remove_partial(struct lxc_container *c, int fd)
218 {
219 int ret;
220 size_t len;
221 char *path;
222
223 close(fd);
224 /* $lxcpath + '/' + $name + '/partial' + \0 */
225 len = strlen(c->config_path) + strlen(c->name) + 10;
226 path = alloca(len);
227 ret = snprintf(path, len, "%s/%s/partial", c->config_path, c->name);
228 if (ret < 0 || (size_t)ret >= len)
229 return;
230
231 ret = unlink(path);
232 if (ret < 0)
233 SYSERROR("Failed to remove partial file %s", path);
234 }
235
236 /* LOCKING
237 * 1. container_mem_lock(c) protects the struct lxc_container from multiple threads.
238 * 2. container_disk_lock(c) protects the on-disk container data - in particular the
239 * container configuration file.
240 * The container_disk_lock also takes the container_mem_lock.
241 * 3. thread_mutex protects process data (ex: fd table) from multiple threads.
242 * NOTHING mutexes two independent programs with their own struct
243 * lxc_container for the same c->name, between API calls. For instance,
244 * c->config_read(); c->start(); Between those calls, data on disk
245 * could change (which shouldn't bother the caller unless for instance
246 * the rootfs get moved). c->config_read(); update; c->config_write();
247 * Two such updaters could race. The callers should therefore check their
248 * results. Trying to prevent that would necessarily expose us to deadlocks
249 * due to hung callers. So I prefer to keep the locks only within our own
250 * functions, not across functions.
251 *
252 * If you're going to clone while holding a lxccontainer, increment
253 * c->numthreads (under privlock) before forking. When deleting,
254 * decrement numthreads under privlock, then if it hits 0 you can delete.
255 * Do not ever use a lxccontainer whose numthreads you did not bump.
256 */
257
258 static void lxc_container_free(struct lxc_container *c)
259 {
260 if (!c)
261 return;
262
263 free(c->configfile);
264 c->configfile = NULL;
265
266 free(c->error_string);
267 c->error_string = NULL;
268
269 if (c->slock) {
270 lxc_putlock(c->slock);
271 c->slock = NULL;
272 }
273
274 if (c->privlock) {
275 lxc_putlock(c->privlock);
276 c->privlock = NULL;
277 }
278
279 free(c->name);
280 c->name = NULL;
281
282 if (c->lxc_conf) {
283 lxc_conf_free(c->lxc_conf);
284 c->lxc_conf = NULL;
285 }
286
287 free(c->config_path);
288 c->config_path = NULL;
289
290 free(c);
291 }
292
293 /* Consider the following case:
294 *
295 * |====================================================================|
296 * | freer | racing get()er |
297 * |====================================================================|
298 * | lxc_container_put() | lxc_container_get() |
299 * | \ lxclock(c->privlock) | c->numthreads < 1? (no) |
300 * | \ c->numthreads = 0 | \ lxclock(c->privlock) -> waits |
301 * | \ lxcunlock() | \ |
302 * | \ lxc_container_free() | \ lxclock() returns |
303 * | | \ c->numthreads < 1 -> return 0 |
304 * | \ \ (free stuff) | |
305 * | \ \ sem_destroy(privlock) | |
306 * |_______________________________|____________________________________|
307 *
308 * When the get()er checks numthreads the first time, one of the following
309 * is true:
310 * 1. freer has set numthreads = 0. get() returns 0
311 * 2. freer is between lxclock and setting numthreads to 0. get()er will
312 * sem_wait on privlock, get lxclock after freer() drops it, then see
313 * numthreads is 0 and exit without touching lxclock again..
314 * 3. freer has not yet locked privlock. If get()er runs first, then put()er
315 * will see --numthreads = 1 and not call lxc_container_free().
316 */
317
318 int lxc_container_get(struct lxc_container *c)
319 {
320 if (!c)
321 return 0;
322
323 /* If someone else has already started freeing the container, don't try
324 * to take the lock, which may be invalid.
325 */
326 if (c->numthreads < 1)
327 return 0;
328
329 if (container_mem_lock(c))
330 return 0;
331
332 /* Bail without trying to unlock, bc the privlock is now probably in
333 * freed memory.
334 */
335 if (c->numthreads < 1)
336 return 0;
337
338 c->numthreads++;
339 container_mem_unlock(c);
340
341 return 1;
342 }
343
344 int lxc_container_put(struct lxc_container *c)
345 {
346 if (!c)
347 return -1;
348
349 if (container_mem_lock(c))
350 return -1;
351
352 c->numthreads--;
353
354 if (c->numthreads < 1) {
355 container_mem_unlock(c);
356 lxc_container_free(c);
357 return 1;
358 }
359
360 container_mem_unlock(c);
361
362 return 0;
363 }
364
365 static bool do_lxcapi_is_defined(struct lxc_container *c)
366 {
367 int statret;
368 struct stat statbuf;
369 bool ret = false;
370
371 if (!c)
372 return false;
373
374 if (container_mem_lock(c))
375 return false;
376
377 if (!c->configfile)
378 goto on_error;
379
380 statret = stat(c->configfile, &statbuf);
381 if (statret != 0)
382 goto on_error;
383
384 ret = true;
385
386 on_error:
387 container_mem_unlock(c);
388
389 return ret;
390 }
391
392 #define WRAP_API(rettype, fnname) \
393 static rettype fnname(struct lxc_container *c) \
394 { \
395 rettype ret; \
396 bool reset_config = false; \
397 \
398 if (!current_config && c && c->lxc_conf) { \
399 current_config = c->lxc_conf; \
400 reset_config = true; \
401 } \
402 \
403 ret = do_##fnname(c); \
404 if (reset_config) \
405 current_config = NULL; \
406 \
407 return ret; \
408 }
409
410 #define WRAP_API_1(rettype, fnname, t1) \
411 static rettype fnname(struct lxc_container *c, t1 a1) \
412 { \
413 rettype ret; \
414 bool reset_config = false; \
415 \
416 if (!current_config && c && c->lxc_conf) { \
417 current_config = c->lxc_conf; \
418 reset_config = true; \
419 } \
420 \
421 ret = do_##fnname(c, a1); \
422 if (reset_config) \
423 current_config = NULL; \
424 \
425 return ret; \
426 }
427
428 #define WRAP_API_2(rettype, fnname, t1, t2) \
429 static rettype fnname(struct lxc_container *c, t1 a1, t2 a2) \
430 { \
431 rettype ret; \
432 bool reset_config = false; \
433 \
434 if (!current_config && c && c->lxc_conf) { \
435 current_config = c->lxc_conf; \
436 reset_config = true; \
437 } \
438 \
439 ret = do_##fnname(c, a1, a2); \
440 if (reset_config) \
441 current_config = NULL; \
442 \
443 return ret; \
444 }
445
446 #define WRAP_API_3(rettype, fnname, t1, t2, t3) \
447 static rettype fnname(struct lxc_container *c, t1 a1, t2 a2, t3 a3) \
448 { \
449 rettype ret; \
450 bool reset_config = false; \
451 \
452 if (!current_config && c && c->lxc_conf) { \
453 current_config = c->lxc_conf; \
454 reset_config = true; \
455 } \
456 \
457 ret = do_##fnname(c, a1, a2, a3); \
458 if (reset_config) \
459 current_config = NULL; \
460 \
461 return ret; \
462 }
463
464 WRAP_API(bool, lxcapi_is_defined)
465
466 static const char *do_lxcapi_state(struct lxc_container *c)
467 {
468 lxc_state_t s;
469
470 if (!c)
471 return NULL;
472
473 s = lxc_getstate(c->name, c->config_path);
474 return lxc_state2str(s);
475 }
476
477 WRAP_API(const char *, lxcapi_state)
478
479 static bool is_stopped(struct lxc_container *c)
480 {
481 lxc_state_t s;
482
483 s = lxc_getstate(c->name, c->config_path);
484 return (s == STOPPED);
485 }
486
487 static bool do_lxcapi_is_running(struct lxc_container *c)
488 {
489 if (!c)
490 return false;
491
492 return !is_stopped(c);
493 }
494
495 WRAP_API(bool, lxcapi_is_running)
496
497 static bool do_lxcapi_freeze(struct lxc_container *c)
498 {
499 int ret;
500
501 if (!c)
502 return false;
503
504 ret = lxc_freeze(c->name, c->config_path);
505 if (ret < 0)
506 return false;
507
508 return true;
509 }
510
511 WRAP_API(bool, lxcapi_freeze)
512
513 static bool do_lxcapi_unfreeze(struct lxc_container *c)
514 {
515 int ret;
516
517 if (!c)
518 return false;
519
520 ret = lxc_unfreeze(c->name, c->config_path);
521 if (ret < 0)
522 return false;
523
524 return true;
525 }
526
527 WRAP_API(bool, lxcapi_unfreeze)
528
529 static int do_lxcapi_console_getfd(struct lxc_container *c, int *ttynum, int *masterfd)
530 {
531 if (!c)
532 return -1;
533
534 return lxc_terminal_getfd(c, ttynum, masterfd);
535 }
536
537 WRAP_API_2(int, lxcapi_console_getfd, int *, int *)
538
539 static int lxcapi_console(struct lxc_container *c, int ttynum, int stdinfd,
540 int stdoutfd, int stderrfd, int escape)
541 {
542 int ret;
543
544 if (!c)
545 return -1;
546
547 current_config = c->lxc_conf;
548 ret = lxc_console(c, ttynum, stdinfd, stdoutfd, stderrfd, escape);
549 current_config = NULL;
550
551 return ret;
552 }
553
554 static int do_lxcapi_console_log(struct lxc_container *c, struct lxc_console_log *log)
555 {
556 int ret;
557
558 ret = lxc_cmd_console_log(c->name, do_lxcapi_get_config_path(c), log);
559 if (ret < 0) {
560 if (ret == -ENODATA)
561 NOTICE("The console log is empty");
562 else if (ret == -EFAULT)
563 NOTICE("The container does not keep a console log");
564 else if (ret == -ENOENT)
565 NOTICE("The container does not keep a console log file");
566 else if (ret == -EIO)
567 NOTICE("Failed to write console log to log file");
568 else
569 ERROR("Failed to retrieve console log");
570 }
571
572 return ret;
573 }
574
575 WRAP_API_1(int, lxcapi_console_log, struct lxc_console_log *)
576
577 static pid_t do_lxcapi_init_pid(struct lxc_container *c)
578 {
579 if (!c)
580 return -1;
581
582 return lxc_cmd_get_init_pid(c->name, c->config_path);
583 }
584
585 WRAP_API(pid_t, lxcapi_init_pid)
586
587 static bool load_config_locked(struct lxc_container *c, const char *fname)
588 {
589 if (!c->lxc_conf)
590 c->lxc_conf = lxc_conf_init();
591
592 if (!c->lxc_conf)
593 return false;
594
595 if (lxc_config_read(fname, c->lxc_conf, false) != 0)
596 return false;
597
598 c->lxc_conf->name = c->name;
599
600 return true;
601 }
602
603 static bool do_lxcapi_load_config(struct lxc_container *c, const char *alt_file)
604 {
605 int lret;
606 const char *fname;
607 bool need_disklock = false, ret = false;
608
609 if (!c)
610 return false;
611
612 fname = c->configfile;
613 if (alt_file)
614 fname = alt_file;
615 if (!fname)
616 return false;
617
618 /* If we're reading something other than the container's config, we only
619 * need to lock the in-memory container. If loading the container's
620 * config file, take the disk lock.
621 */
622 if (strcmp(fname, c->configfile) == 0)
623 need_disklock = true;
624
625 if (need_disklock)
626 lret = container_disk_lock(c);
627 else
628 lret = container_mem_lock(c);
629 if (lret)
630 return false;
631
632 ret = load_config_locked(c, fname);
633
634 if (need_disklock)
635 container_disk_unlock(c);
636 else
637 container_mem_unlock(c);
638
639 return ret;
640 }
641
642 WRAP_API_1(bool, lxcapi_load_config, const char *)
643
644 static bool do_lxcapi_want_daemonize(struct lxc_container *c, bool state)
645 {
646 if (!c || !c->lxc_conf)
647 return false;
648
649 if (container_mem_lock(c))
650 return false;
651
652 c->daemonize = state;
653
654 container_mem_unlock(c);
655
656 return true;
657 }
658
659 WRAP_API_1(bool, lxcapi_want_daemonize, bool)
660
661 static bool do_lxcapi_want_close_all_fds(struct lxc_container *c, bool state)
662 {
663 if (!c || !c->lxc_conf)
664 return false;
665
666 if (container_mem_lock(c))
667 return false;
668
669 c->lxc_conf->close_all_fds = state;
670
671 container_mem_unlock(c);
672
673 return true;
674 }
675
676 WRAP_API_1(bool, lxcapi_want_close_all_fds, bool)
677
678 static bool do_lxcapi_wait(struct lxc_container *c, const char *state,
679 int timeout)
680 {
681 int ret;
682
683 if (!c)
684 return false;
685
686 ret = lxc_wait(c->name, state, timeout, c->config_path);
687 return ret == 0;
688 }
689
690 WRAP_API_2(bool, lxcapi_wait, const char *, int)
691
692 static bool am_single_threaded(void)
693 {
694 DIR *dir;
695 struct dirent *direntp;
696 int count = 0;
697
698 dir = opendir("/proc/self/task");
699 if (!dir)
700 return false;
701
702 while ((direntp = readdir(dir))) {
703 if (strcmp(direntp->d_name, ".") == 0)
704 continue;
705
706 if (strcmp(direntp->d_name, "..") == 0)
707 continue;
708
709 count++;
710 if (count > 1)
711 break;
712 }
713 closedir(dir);
714
715 return count == 1;
716 }
717
718 static void push_arg(char ***argp, char *arg, int *nargs)
719 {
720 char *copy;
721 char **argv;
722
723 copy = must_copy_string(arg);
724
725 do {
726 argv = realloc(*argp, (*nargs + 2) * sizeof(char *));
727 } while (!argv);
728
729 *argp = argv;
730 argv[*nargs] = copy;
731 (*nargs)++;
732 argv[*nargs] = NULL;
733 }
734
735 static char **split_init_cmd(const char *incmd)
736 {
737 size_t len, retlen;
738 char *copy, *p;
739 char **argv;
740 int nargs = 0;
741 char *saveptr = NULL;
742
743 if (!incmd)
744 return NULL;
745
746 len = strlen(incmd) + 1;
747 copy = alloca(len);
748 retlen = strlcpy(copy, incmd, len);
749 if (retlen >= len) {
750 return NULL;
751 }
752
753 do {
754 argv = malloc(sizeof(char *));
755 } while (!argv);
756
757 argv[0] = NULL;
758 for (; (p = strtok_r(copy, " ", &saveptr)); copy = NULL)
759 push_arg(&argv, p, &nargs);
760
761 if (nargs == 0) {
762 free(argv);
763 return NULL;
764 }
765
766 return argv;
767 }
768
769 static void free_init_cmd(char **argv)
770 {
771 int i = 0;
772
773 if (!argv)
774 return;
775
776 while (argv[i])
777 free(argv[i++]);
778
779 free(argv);
780 }
781
782 static int lxc_rcv_status(int state_socket)
783 {
784 int ret;
785 int state = -1;
786
787 again:
788 /* Receive container state. */
789 ret = lxc_abstract_unix_rcv_credential(state_socket, &state,
790 sizeof(int));
791 if (ret <= 0) {
792 if (errno != EINTR)
793 return -1;
794 TRACE("Caught EINTR; retrying");
795 goto again;
796 }
797
798 return state;
799 }
800
801 static bool wait_on_daemonized_start(struct lxc_handler *handler, int pid)
802 {
803 int ret, state;
804
805 /* Close write end of the socket pair. */
806 close(handler->state_socket_pair[1]);
807 handler->state_socket_pair[1] = -1;
808
809 state = lxc_rcv_status(handler->state_socket_pair[0]);
810
811 /* Close read end of the socket pair. */
812 close(handler->state_socket_pair[0]);
813 handler->state_socket_pair[0] = -1;
814
815 /* The first child is going to fork() again and then exits. So we reap
816 * the first child here.
817 */
818 ret = wait_for_pid(pid);
819 if (ret < 0)
820 DEBUG("Failed waiting on first child %d", pid);
821 else
822 DEBUG("First child %d exited", pid);
823
824 if (state < 0) {
825 SYSERROR("Failed to receive the container state");
826 return false;
827 }
828
829 /* If we receive anything else then running we know that the container
830 * failed to start.
831 */
832 if (state != RUNNING) {
833 ERROR("Received container state \"%s\" instead of \"RUNNING\"",
834 lxc_state2str(state));
835 return false;
836 }
837
838 TRACE("Container is in \"RUNNING\" state");
839 return true;
840 }
841
842 static bool do_lxcapi_start(struct lxc_container *c, int useinit, char * const argv[])
843 {
844 int ret;
845 struct lxc_handler *handler;
846 struct lxc_conf *conf;
847 char *default_args[] = {
848 "/sbin/init",
849 NULL,
850 };
851 char **init_cmd = NULL;
852 int keepfds[3] = {-1, -1, -1};
853
854 /* container does exist */
855 if (!c)
856 return false;
857
858 /* If anything fails before we set error_num, we want an error in there.
859 */
860 c->error_num = 1;
861
862 /* Container has not been setup. */
863 if (!c->lxc_conf)
864 return false;
865
866 ret = ongoing_create(c);
867 if (ret < 0) {
868 ERROR("Failed checking for incomplete container creation");
869 return false;
870 } else if (ret == 1) {
871 ERROR("Ongoing container creation detected");
872 return false;
873 } else if (ret == 2) {
874 ERROR("Failed to create container");
875 do_lxcapi_destroy(c);
876 return false;
877 }
878
879 if (container_mem_lock(c))
880 return false;
881
882 conf = c->lxc_conf;
883
884 /* initialize handler */
885 handler = lxc_init_handler(c->name, conf, c->config_path, c->daemonize);
886
887 container_mem_unlock(c);
888 if (!handler)
889 return false;
890
891 if (!argv) {
892 if (useinit && conf->execute_cmd)
893 argv = init_cmd = split_init_cmd(conf->execute_cmd);
894 else
895 argv = init_cmd = split_init_cmd(conf->init_cmd);
896 }
897
898 /* ... otherwise use default_args. */
899 if (!argv) {
900 if (useinit) {
901 ERROR("No valid init detected");
902 lxc_free_handler(handler);
903 return false;
904 }
905 argv = default_args;
906 }
907
908 /* I'm not sure what locks we want here.Any? Is liblxc's locking enough
909 * here to protect the on disk container? We don't want to exclude
910 * things like lxc_info while the container is running.
911 */
912 if (c->daemonize) {
913 bool started;
914 char title[2048];
915 pid_t pid;
916
917 pid = fork();
918 if (pid < 0) {
919 free_init_cmd(init_cmd);
920 lxc_free_handler(handler);
921 return false;
922 }
923
924 /* first parent */
925 if (pid != 0) {
926 /* Set to NULL because we don't want father unlink
927 * the PID file, child will do the free and unlink.
928 */
929 c->pidfile = NULL;
930
931 /* Wait for container to tell us whether it started
932 * successfully.
933 */
934 started = wait_on_daemonized_start(handler, pid);
935
936 free_init_cmd(init_cmd);
937 lxc_free_handler(handler);
938 return started;
939 }
940
941 /* first child */
942
943 /* We don't really care if this doesn't print all the
944 * characters. All that it means is that the proctitle will be
945 * ugly. Similarly, we also don't care if setproctitle() fails.
946 * */
947 (void)snprintf(title, sizeof(title), "[lxc monitor] %s %s", c->config_path, c->name);
948 INFO("Attempting to set proc title to %s", title);
949 (void)setproctitle(title);
950
951 /* We fork() a second time to be reparented to init. Like
952 * POSIX's daemon() function we change to "/" and redirect
953 * std{in,out,err} to /dev/null.
954 */
955 pid = fork();
956 if (pid < 0) {
957 SYSERROR("Failed to fork first child process");
958 _exit(EXIT_FAILURE);
959 }
960
961 /* second parent */
962 if (pid != 0) {
963 free_init_cmd(init_cmd);
964 lxc_free_handler(handler);
965 _exit(EXIT_SUCCESS);
966 }
967
968 /* second child */
969
970 /* change to / directory */
971 ret = chdir("/");
972 if (ret < 0) {
973 SYSERROR("Failed to change to \"/\" directory");
974 _exit(EXIT_FAILURE);
975 }
976
977 keepfds[0] = handler->conf->maincmd_fd;
978 keepfds[1] = handler->state_socket_pair[0];
979 keepfds[2] = handler->state_socket_pair[1];
980 ret = lxc_check_inherited(conf, true, keepfds,
981 sizeof(keepfds) / sizeof(keepfds[0]));
982 if (ret < 0)
983 _exit(EXIT_FAILURE);
984
985 /* redirect std{in,out,err} to /dev/null */
986 ret = null_stdfds();
987 if (ret < 0) {
988 ERROR("Failed to redirect std{in,out,err} to /dev/null");
989 _exit(EXIT_FAILURE);
990 }
991
992 /* become session leader */
993 ret = setsid();
994 if (ret < 0)
995 TRACE("Process %d is already process group leader", lxc_raw_getpid());
996 } else {
997 if (!am_single_threaded()) {
998 ERROR("Cannot start non-daemonized container when threaded");
999 free_init_cmd(init_cmd);
1000 lxc_free_handler(handler);
1001 return false;
1002 }
1003 }
1004
1005 /* We need to write PID file after daemonize, so we always
1006 * write the right PID.
1007 */
1008 if (c->pidfile) {
1009 int ret, w;
1010 char pidstr[LXC_NUMSTRLEN64];
1011
1012 w = snprintf(pidstr, LXC_NUMSTRLEN64, "%d", (int)lxc_raw_getpid());
1013 if (w < 0 || (size_t)w >= LXC_NUMSTRLEN64) {
1014 free_init_cmd(init_cmd);
1015 lxc_free_handler(handler);
1016
1017 SYSERROR("Failed to write monitor pid to \"%s\"", c->pidfile);
1018
1019 if (c->daemonize)
1020 _exit(EXIT_FAILURE);
1021
1022 return false;
1023 }
1024
1025 ret = lxc_write_to_file(c->pidfile, pidstr, w, false, 0600);
1026 if (ret < 0) {
1027 free_init_cmd(init_cmd);
1028 lxc_free_handler(handler);
1029
1030 SYSERROR("Failed to write '%s'", c->pidfile);
1031
1032 if (c->daemonize)
1033 _exit(EXIT_FAILURE);
1034
1035 return false;
1036 }
1037 }
1038
1039 conf->reboot = REBOOT_NONE;
1040
1041 /* Unshare the mount namespace if requested */
1042 if (conf->monitor_unshare) {
1043 ret = unshare(CLONE_NEWNS);
1044 if (ret < 0) {
1045 SYSERROR("failed to unshare mount namespace");
1046 lxc_free_handler(handler);
1047 ret = 1;
1048 goto on_error;
1049 }
1050
1051 ret = mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL);
1052 if (ret < 0) {
1053 SYSERROR("Failed to make / rslave at startup");
1054 lxc_free_handler(handler);
1055 ret = 1;
1056 goto on_error;
1057 }
1058 }
1059
1060 reboot:
1061 if (conf->reboot == REBOOT_INIT) {
1062 /* initialize handler */
1063 handler = lxc_init_handler(c->name, conf, c->config_path, c->daemonize);
1064 if (!handler) {
1065 ret = 1;
1066 goto on_error;
1067 }
1068 }
1069
1070 keepfds[0] = handler->conf->maincmd_fd;
1071 keepfds[1] = handler->state_socket_pair[0];
1072 keepfds[2] = handler->state_socket_pair[1];
1073 ret = lxc_check_inherited(conf, c->daemonize, keepfds,
1074 sizeof(keepfds) / sizeof(keepfds[0]));
1075 if (ret < 0) {
1076 lxc_free_handler(handler);
1077 ret = 1;
1078 goto on_error;
1079 }
1080
1081 if (useinit)
1082 ret = lxc_execute(c->name, argv, 1, handler, c->config_path,
1083 c->daemonize, &c->error_num);
1084 else
1085 ret = lxc_start(c->name, argv, handler, c->config_path,
1086 c->daemonize, &c->error_num);
1087
1088 if (conf->reboot == REBOOT_REQ) {
1089 INFO("Container requested reboot");
1090 conf->reboot = REBOOT_INIT;
1091 goto reboot;
1092 }
1093
1094 on_error:
1095 if (c->pidfile) {
1096 unlink(c->pidfile);
1097 free(c->pidfile);
1098 c->pidfile = NULL;
1099 }
1100 free_init_cmd(init_cmd);
1101
1102 if (c->daemonize && ret != 0)
1103 _exit(EXIT_FAILURE);
1104 else if (c->daemonize)
1105 _exit(EXIT_SUCCESS);
1106
1107 if (ret != 0)
1108 return false;
1109
1110 return true;
1111 }
1112
1113 static bool lxcapi_start(struct lxc_container *c, int useinit,
1114 char *const argv[])
1115 {
1116 bool ret;
1117
1118 current_config = c ? c->lxc_conf : NULL;
1119 ret = do_lxcapi_start(c, useinit, argv);
1120 current_config = NULL;
1121
1122 return ret;
1123 }
1124
1125 /* Note, there MUST be an ending NULL. */
1126 static bool lxcapi_startl(struct lxc_container *c, int useinit, ...)
1127 {
1128 va_list ap;
1129 char **inargs = NULL;
1130 bool bret = false;
1131
1132 /* container exists */
1133 if (!c)
1134 return false;
1135
1136 current_config = c->lxc_conf;
1137
1138 va_start(ap, useinit);
1139 inargs = lxc_va_arg_list_to_argv(ap, 0, 1);
1140 va_end(ap);
1141 if (!inargs)
1142 goto on_error;
1143
1144 /* pass NULL if no arguments were supplied */
1145 bret = do_lxcapi_start(c, useinit, *inargs ? inargs : NULL);
1146
1147 on_error:
1148 if (inargs) {
1149 char **arg;
1150 for (arg = inargs; *arg; arg++)
1151 free(*arg);
1152 free(inargs);
1153 }
1154
1155 current_config = NULL;
1156
1157 return bret;
1158 }
1159
1160 static bool do_lxcapi_stop(struct lxc_container *c)
1161 {
1162 int ret;
1163
1164 if (!c)
1165 return false;
1166
1167 ret = lxc_cmd_stop(c->name, c->config_path);
1168
1169 return ret == 0;
1170 }
1171
1172 WRAP_API(bool, lxcapi_stop)
1173
1174 static int do_create_container_dir(const char *path, struct lxc_conf *conf)
1175 {
1176 int lasterr;
1177 size_t len;
1178 char *p;
1179 int ret = -1;
1180
1181 mode_t mask = umask(0002);
1182 ret = mkdir(path, 0770);
1183 lasterr = errno;
1184 umask(mask);
1185 errno = lasterr;
1186 if (ret) {
1187 if (errno != EEXIST)
1188 return -1;
1189
1190 ret = 0;
1191 }
1192
1193 len = strlen(path);
1194 p = alloca(len + 1);
1195 strcpy(p, path);
1196 if (!lxc_list_empty(&conf->id_map)) {
1197 ret = chown_mapped_root(p, conf);
1198 if (ret < 0)
1199 ret = -1;
1200 }
1201
1202 return ret;
1203 }
1204
1205 /* Create the standard expected container dir. */
1206 static bool create_container_dir(struct lxc_container *c)
1207 {
1208 int ret;
1209 size_t len;
1210 char *s;
1211
1212 len = strlen(c->config_path) + strlen(c->name) + 2;
1213 s = malloc(len);
1214 if (!s)
1215 return false;
1216
1217 ret = snprintf(s, len, "%s/%s", c->config_path, c->name);
1218 if (ret < 0 || (size_t)ret >= len) {
1219 free(s);
1220 return false;
1221 }
1222
1223 ret = do_create_container_dir(s, c->lxc_conf);
1224 free(s);
1225
1226 return ret == 0;
1227 }
1228
1229 /* do_storage_create: thin wrapper around storage_create(). Like
1230 * storage_create(), it returns a mounted bdev on success, NULL on error.
1231 */
1232 static struct lxc_storage *do_storage_create(struct lxc_container *c,
1233 const char *type,
1234 struct bdev_specs *specs)
1235 {
1236 int ret;
1237 size_t len;
1238 char *dest;
1239 struct lxc_storage *bdev;
1240
1241 /* rootfs.path or lxcpath/lxcname/rootfs */
1242 if (c->lxc_conf->rootfs.path &&
1243 (access(c->lxc_conf->rootfs.path, F_OK) == 0)) {
1244 const char *rpath = c->lxc_conf->rootfs.path;
1245 len = strlen(rpath) + 1;
1246 dest = alloca(len);
1247 ret = snprintf(dest, len, "%s", rpath);
1248 } else {
1249 const char *lxcpath = do_lxcapi_get_config_path(c);
1250 len = strlen(c->name) + strlen(lxcpath) + 9;
1251 dest = alloca(len);
1252 ret = snprintf(dest, len, "%s/%s/rootfs", lxcpath, c->name);
1253 }
1254 if (ret < 0 || (size_t)ret >= len)
1255 return NULL;
1256
1257 bdev = storage_create(dest, type, c->name, specs);
1258 if (!bdev) {
1259 ERROR("Failed to create \"%s\" storage", type);
1260 return NULL;
1261 }
1262
1263 if (!c->set_config_item(c, "lxc.rootfs.path", bdev->src)) {
1264 ERROR("Failed to set \"lxc.rootfs.path = %s\"", bdev->src);
1265 return NULL;
1266 }
1267
1268 /* If we are not root, chown the rootfs dir to root in the target user
1269 * namespace.
1270 */
1271 ret = geteuid();
1272 if (ret != 0 || (c->lxc_conf && !lxc_list_empty(&c->lxc_conf->id_map))) {
1273 ret = chown_mapped_root(bdev->dest, c->lxc_conf);
1274 if (ret < 0) {
1275 ERROR("Error chowning \"%s\" to container root", bdev->dest);
1276 suggest_default_idmap();
1277 storage_put(bdev);
1278 return NULL;
1279 }
1280 }
1281
1282 return bdev;
1283 }
1284
1285 static char *lxcbasename(char *path)
1286 {
1287 char *p;
1288
1289 p = path + strlen(path) - 1;
1290 while (*p != '/' && p > path)
1291 p--;
1292
1293 return p;
1294 }
1295
1296 static bool create_run_template(struct lxc_container *c, char *tpath,
1297 bool need_null_stdfds, char *const argv[])
1298 {
1299 int ret;
1300 pid_t pid;
1301
1302 if (!tpath)
1303 return true;
1304
1305 pid = fork();
1306 if (pid < 0) {
1307 SYSERROR("Failed to fork task for container creation template");
1308 return false;
1309 }
1310
1311 if (pid == 0) { /* child */
1312 int i, len;
1313 char *namearg, *patharg, *rootfsarg;
1314 char **newargv;
1315 int nargs = 0;
1316 struct lxc_storage *bdev = NULL;
1317 struct lxc_conf *conf = c->lxc_conf;
1318 uid_t euid;
1319
1320 if (need_null_stdfds) {
1321 ret = null_stdfds();
1322 if (ret < 0)
1323 _exit(EXIT_FAILURE);
1324 }
1325
1326 bdev = storage_init(c->lxc_conf);
1327 if (!bdev) {
1328 ERROR("Failed to initialize storage");
1329 _exit(EXIT_FAILURE);
1330 }
1331
1332 euid = geteuid();
1333 if (euid == 0) {
1334 ret = unshare(CLONE_NEWNS);
1335 if (ret < 0) {
1336 ERROR("Failed to unshare CLONE_NEWNS");
1337 _exit(EXIT_FAILURE);
1338 }
1339
1340 ret = detect_shared_rootfs();
1341 if (ret == 1) {
1342 ret = mount(NULL, "/", NULL, MS_SLAVE | MS_REC, NULL);
1343 if (ret < 0) {
1344 SYSERROR("Failed to make \"/\" rslave");
1345 ERROR("Continuing...");
1346 }
1347 }
1348 }
1349
1350 if (strcmp(bdev->type, "dir") != 0 && strcmp(bdev->type, "btrfs") != 0) {
1351 if (euid != 0) {
1352 ERROR("Unprivileged users can only create "
1353 "btrfs and directory-backed containers");
1354 _exit(EXIT_FAILURE);
1355 }
1356
1357 if (strcmp(bdev->type, "overlay") == 0 ||
1358 strcmp(bdev->type, "overlayfs") == 0) {
1359 /* If we create an overlay container we need to
1360 * rsync the contents into
1361 * <container-path>/<container-name>/rootfs.
1362 * However, the overlay mount function will
1363 * mount will mount
1364 * <container-path>/<container-name>/delta0
1365 * over
1366 * <container-path>/<container-name>/rootfs
1367 * which means we would rsync the rootfs into
1368 * the delta directory. That doesn't make sense
1369 * since the delta directory only exists to
1370 * record the differences to
1371 * <container-path>/<container-name>/rootfs. So
1372 * let's simply bind-mount here and then rsync
1373 * directly into
1374 * <container-path>/<container-name>/rootfs.
1375 */
1376 char *src;
1377
1378 src = ovl_get_rootfs(bdev->src, &(size_t){0});
1379 if (!src) {
1380 ERROR("Failed to get rootfs");
1381 _exit(EXIT_FAILURE);
1382 }
1383
1384 ret = mount(src, bdev->dest, "bind", MS_BIND | MS_REC, NULL);
1385 if (ret < 0) {
1386 ERROR("Failed to mount rootfs");
1387 return -1;
1388 }
1389 } else {
1390 ret = bdev->ops->mount(bdev);
1391 if (ret < 0) {
1392 ERROR("Failed to mount rootfs");
1393 _exit(EXIT_FAILURE);
1394 }
1395 }
1396 } else { /* TODO come up with a better way here! */
1397 const char *src;
1398 free(bdev->dest);
1399 src = lxc_storage_get_path(bdev->src, bdev->type);
1400 bdev->dest = strdup(src);
1401 }
1402
1403 /* Create our new array, pre-pend the template name and base
1404 * args.
1405 */
1406 if (argv)
1407 for (nargs = 0; argv[nargs]; nargs++) {
1408 ;
1409 }
1410 /* template, path, rootfs and name args */
1411 nargs += 4;
1412
1413 newargv = malloc(nargs * sizeof(*newargv));
1414 if (!newargv)
1415 _exit(EXIT_FAILURE);
1416 newargv[0] = lxcbasename(tpath);
1417
1418 /* --path */
1419 len = strlen(c->config_path) + strlen(c->name) + strlen("--path=") + 2;
1420 patharg = malloc(len);
1421 if (!patharg)
1422 _exit(EXIT_FAILURE);
1423 ret = snprintf(patharg, len, "--path=%s/%s", c->config_path, c->name);
1424 if (ret < 0 || ret >= len)
1425 _exit(EXIT_FAILURE);
1426 newargv[1] = patharg;
1427
1428 /* --name */
1429 len = strlen("--name=") + strlen(c->name) + 1;
1430 namearg = malloc(len);
1431 if (!namearg)
1432 _exit(EXIT_FAILURE);
1433 ret = snprintf(namearg, len, "--name=%s", c->name);
1434 if (ret < 0 || ret >= len)
1435 _exit(EXIT_FAILURE);
1436 newargv[2] = namearg;
1437
1438 /* --rootfs */
1439 len = strlen("--rootfs=") + 1 + strlen(bdev->dest);
1440 rootfsarg = malloc(len);
1441 if (!rootfsarg)
1442 _exit(EXIT_FAILURE);
1443 ret = snprintf(rootfsarg, len, "--rootfs=%s", bdev->dest);
1444 if (ret < 0 || ret >= len)
1445 _exit(EXIT_FAILURE);
1446 newargv[3] = rootfsarg;
1447
1448 /* add passed-in args */
1449 if (argv)
1450 for (i = 4; i < nargs; i++)
1451 newargv[i] = argv[i - 4];
1452
1453 /* add trailing NULL */
1454 nargs++;
1455 newargv = realloc(newargv, nargs * sizeof(*newargv));
1456 if (!newargv)
1457 _exit(EXIT_FAILURE);
1458 newargv[nargs - 1] = NULL;
1459
1460 /* If we're running the template in a mapped userns, then we
1461 * prepend the template command with: lxc-usernsexec <-m map1>
1462 * ... <-m mapn> -- and we append "--mapped-uid x", where x is
1463 * the mapped uid for our geteuid()
1464 */
1465 if (!lxc_list_empty(&conf->id_map)) {
1466 int extraargs, hostuid_mapped, hostgid_mapped;
1467 char **n2;
1468 char txtuid[20], txtgid[20];
1469 struct lxc_list *it;
1470 struct id_map *map;
1471 int n2args = 1;
1472
1473 n2 = malloc(n2args * sizeof(*n2));
1474 if (!n2)
1475 _exit(EXIT_FAILURE);
1476
1477 newargv[0] = tpath;
1478 tpath = "lxc-usernsexec";
1479 n2[0] = "lxc-usernsexec";
1480 lxc_list_for_each(it, &conf->id_map) {
1481 map = it->elem;
1482 n2args += 2;
1483 n2 = realloc(n2, n2args * sizeof(char *));
1484 if (!n2)
1485 _exit(EXIT_FAILURE);
1486
1487 n2[n2args - 2] = "-m";
1488 n2[n2args - 1] = malloc(200);
1489 if (!n2[n2args - 1])
1490 _exit(EXIT_FAILURE);
1491
1492 ret = snprintf(n2[n2args - 1], 200, "%c:%lu:%lu:%lu",
1493 map->idtype == ID_TYPE_UID ? 'u' : 'g',
1494 map->nsid, map->hostid, map->range);
1495 if (ret < 0 || ret >= 200)
1496 _exit(EXIT_FAILURE);
1497 }
1498
1499 hostuid_mapped = mapped_hostid(geteuid(), conf, ID_TYPE_UID);
1500 extraargs = hostuid_mapped >= 0 ? 1 : 3;
1501 n2 = realloc(n2, (nargs + n2args + extraargs) * sizeof(char *));
1502 if (!n2)
1503 _exit(EXIT_FAILURE);
1504
1505 if (hostuid_mapped < 0) {
1506 hostuid_mapped = find_unmapped_nsid(conf, ID_TYPE_UID);
1507 n2[n2args++] = "-m";
1508 if (hostuid_mapped < 0) {
1509 ERROR("Failed to find free uid to map");
1510 _exit(EXIT_FAILURE);
1511 }
1512
1513 n2[n2args++] = malloc(200);
1514 if (!n2[n2args - 1]) {
1515 SYSERROR("out of memory");
1516 _exit(EXIT_FAILURE);
1517 }
1518 ret = snprintf(n2[n2args - 1], 200, "u:%d:%d:1",
1519 hostuid_mapped, geteuid());
1520 if (ret < 0 || ret >= 200)
1521 _exit(EXIT_FAILURE);
1522 }
1523
1524 hostgid_mapped = mapped_hostid(getegid(), conf, ID_TYPE_GID);
1525 extraargs = hostgid_mapped >= 0 ? 1 : 3;
1526 n2 = realloc(n2, (nargs + n2args + extraargs) * sizeof(char *));
1527 if (!n2)
1528 _exit(EXIT_FAILURE);
1529
1530 if (hostgid_mapped < 0) {
1531 hostgid_mapped = find_unmapped_nsid(conf, ID_TYPE_GID);
1532 n2[n2args++] = "-m";
1533 if (hostgid_mapped < 0) {
1534 ERROR("Failed to find free gid to map");
1535 _exit(EXIT_FAILURE);
1536 }
1537
1538 n2[n2args++] = malloc(200);
1539 if (!n2[n2args - 1]) {
1540 SYSERROR("out of memory");
1541 _exit(EXIT_FAILURE);
1542 }
1543
1544 ret = snprintf(n2[n2args - 1], 200, "g:%d:%d:1",
1545 hostgid_mapped, getegid());
1546 if (ret < 0 || ret >= 200)
1547 _exit(EXIT_FAILURE);
1548 }
1549 n2[n2args++] = "--";
1550 for (i = 0; i < nargs; i++)
1551 n2[i + n2args] = newargv[i];
1552 n2args += nargs;
1553
1554 /* Finally add "--mapped-uid $uid" to tell template what
1555 * to chown cached images to.
1556 */
1557 n2args += 4;
1558 n2 = realloc(n2, n2args * sizeof(char *));
1559 if (!n2)
1560 _exit(EXIT_FAILURE);
1561
1562 /* note n2[n2args-1] is NULL */
1563 n2[n2args - 5] = "--mapped-uid";
1564 snprintf(txtuid, 20, "%d", hostuid_mapped);
1565 n2[n2args - 4] = txtuid;
1566 n2[n2args - 3] = "--mapped-gid";
1567 snprintf(txtgid, 20, "%d", hostgid_mapped);
1568 n2[n2args - 2] = txtgid;
1569 n2[n2args - 1] = NULL;
1570 free(newargv);
1571 newargv = n2;
1572 }
1573
1574 execvp(tpath, newargv);
1575 SYSERROR("Failed to execute template %s", tpath);
1576 _exit(EXIT_FAILURE);
1577 }
1578
1579 ret = wait_for_pid(pid);
1580 if (ret != 0) {
1581 ERROR("Failed to create container from template");
1582 return false;
1583 }
1584
1585 return true;
1586 }
1587
1588 static bool prepend_lxc_header(char *path, const char *t, char *const argv[])
1589 {
1590 long flen;
1591 size_t len;
1592 char *contents;
1593 FILE *f;
1594 int ret = -1;
1595 #if HAVE_LIBGNUTLS
1596 int i;
1597 unsigned char md_value[SHA_DIGEST_LENGTH];
1598 char *tpath;
1599 #endif
1600
1601 f = fopen(path, "r");
1602 if (f == NULL)
1603 return false;
1604
1605 ret = fseek(f, 0, SEEK_END);
1606 if (ret < 0)
1607 goto out_error;
1608
1609 ret = -1;
1610 flen = ftell(f);
1611 if (flen < 0)
1612 goto out_error;
1613
1614 ret = fseek(f, 0, SEEK_SET);
1615 if (ret < 0)
1616 goto out_error;
1617
1618 ret = fseek(f, 0, SEEK_SET);
1619 if (ret < 0)
1620 goto out_error;
1621
1622 ret = -1;
1623 contents = malloc(flen + 1);
1624 if (!contents)
1625 goto out_error;
1626
1627 len = fread(contents, 1, flen, f);
1628 if (len != flen)
1629 goto out_free_contents;
1630
1631 contents[flen] = '\0';
1632 ret = fclose(f);
1633 f = NULL;
1634 if (ret < 0)
1635 goto out_free_contents;
1636
1637 #if HAVE_LIBGNUTLS
1638 tpath = get_template_path(t);
1639 if (!tpath) {
1640 ERROR("Invalid template \"%s\" specified", t);
1641 goto out_free_contents;
1642 }
1643
1644 ret = sha1sum_file(tpath, md_value);
1645 if (ret < 0) {
1646 ERROR("Failed to get sha1sum of %s", tpath);
1647 free(tpath);
1648 goto out_free_contents;
1649 }
1650 free(tpath);
1651 #endif
1652
1653 f = fopen(path, "w");
1654 if (f == NULL) {
1655 SYSERROR("Reopening config for writing");
1656 free(contents);
1657 return false;
1658 }
1659
1660 fprintf(f, "# Template used to create this container: %s\n", t);
1661 if (argv) {
1662 fprintf(f, "# Parameters passed to the template:");
1663 while (*argv) {
1664 fprintf(f, " %s", *argv);
1665 argv++;
1666 }
1667 fprintf(f, "\n");
1668 }
1669 #if HAVE_LIBGNUTLS
1670 fprintf(f, "# Template script checksum (SHA-1): ");
1671 for (i=0; i<SHA_DIGEST_LENGTH; i++)
1672 fprintf(f, "%02x", md_value[i]);
1673 fprintf(f, "\n");
1674 #endif
1675 fprintf(f, "# For additional config options, please look at lxc.container.conf(5)\n");
1676 fprintf(f, "\n# Uncomment the following line to support nesting containers:\n");
1677 fprintf(f, "#lxc.include = " LXCTEMPLATECONFIG "/nesting.conf\n");
1678 fprintf(f, "# (Be aware this has security implications)\n\n");
1679 if (fwrite(contents, 1, flen, f) != flen) {
1680 SYSERROR("Writing original contents");
1681 free(contents);
1682 fclose(f);
1683 return false;
1684 }
1685
1686 ret = 0;
1687
1688 out_free_contents:
1689 free(contents);
1690
1691 out_error:
1692 if (f) {
1693 int newret;
1694 newret = fclose(f);
1695 if (ret == 0)
1696 ret = newret;
1697 }
1698
1699 if (ret < 0) {
1700 SYSERROR("Error prepending header");
1701 return false;
1702 }
1703
1704 return true;
1705 }
1706
1707 static void lxcapi_clear_config(struct lxc_container *c)
1708 {
1709 if (!c || !c->lxc_conf)
1710 return;
1711
1712 lxc_conf_free(c->lxc_conf);
1713 c->lxc_conf = NULL;
1714 }
1715
1716 #define do_lxcapi_clear_config(c) lxcapi_clear_config(c)
1717
1718 /*
1719 * lxcapi_create:
1720 * create a container with the given parameters.
1721 * @c: container to be created. It has the lxcpath, name, and a starting
1722 * configuration already set
1723 * @t: the template to execute to instantiate the root filesystem and
1724 * adjust the configuration.
1725 * @bdevtype: backing store type to use. If NULL, dir will be used.
1726 * @specs: additional parameters for the backing store, i.e. LVM vg to
1727 * use.
1728 *
1729 * @argv: the arguments to pass to the template, terminated by NULL. If no
1730 * arguments, you can just pass NULL.
1731 */
1732 static bool do_lxcapi_create(struct lxc_container *c, const char *t,
1733 const char *bdevtype, struct bdev_specs *specs,
1734 int flags, char *const argv[])
1735 {
1736 int partial_fd;
1737 mode_t mask;
1738 pid_t pid;
1739 bool ret = false;
1740 char *tpath = NULL;
1741
1742 if (!c)
1743 return false;
1744
1745 if (t) {
1746 tpath = get_template_path(t);
1747 if (!tpath) {
1748 ERROR("Unknown template \"%s\"", t);
1749 goto out;
1750 }
1751 }
1752
1753 /* If a template is passed in, and the rootfs already is defined in the
1754 * container config and exists, then the caller is trying to create an
1755 * existing container. Return an error, but do NOT delete the container.
1756 */
1757 if (do_lxcapi_is_defined(c) && c->lxc_conf && c->lxc_conf->rootfs.path &&
1758 access(c->lxc_conf->rootfs.path, F_OK) == 0 && tpath) {
1759 ERROR("Container \"%s\" already exists in \"%s\"", c->name,
1760 c->config_path);
1761 goto free_tpath;
1762 }
1763
1764 if (!c->lxc_conf) {
1765 if (!do_lxcapi_load_config(c, lxc_global_config_value("lxc.default_config"))) {
1766 ERROR("Error loading default configuration file %s",
1767 lxc_global_config_value("lxc.default_config"));
1768 goto free_tpath;
1769 }
1770 }
1771
1772 if (!create_container_dir(c))
1773 goto free_tpath;
1774
1775 /* If both template and rootfs.path are set, template is setup as
1776 * rootfs.path. The container is already created if we have a config and
1777 * rootfs.path is accessible
1778 */
1779 if (!c->lxc_conf->rootfs.path && !tpath) {
1780 /* No template passed in and rootfs does not exist. */
1781 if (!c->save_config(c, NULL)) {
1782 ERROR("Failed to save initial config for \"%s\"", c->name);
1783 goto out;
1784 }
1785 ret = true;
1786 goto out;
1787 }
1788
1789 /* Rootfs passed into configuration, but does not exist. */
1790 if (c->lxc_conf->rootfs.path && access(c->lxc_conf->rootfs.path, F_OK) != 0)
1791 goto out;
1792
1793 if (do_lxcapi_is_defined(c) && c->lxc_conf->rootfs.path && !tpath) {
1794 /* Rootfs already existed, user just wanted to save the loaded
1795 * configuration.
1796 */
1797 if (!c->save_config(c, NULL))
1798 ERROR("Failed to save initial config for \"%s\"", c->name);
1799 ret = true;
1800 goto out;
1801 }
1802
1803 /* Mark that this container is being created */
1804 partial_fd = create_partial(c);
1805 if (partial_fd < 0)
1806 goto out;
1807
1808 /* No need to get disk lock bc we have the partial lock. */
1809
1810 mask = umask(0022);
1811
1812 /* Create the storage.
1813 * Note we can't do this in the same task as we use to execute the
1814 * template because of the way zfs works.
1815 * After you 'zfs create', zfs mounts the fs only in the initial
1816 * namespace.
1817 */
1818 pid = fork();
1819 if (pid < 0) {
1820 SYSERROR("Failed to fork task for container creation template");
1821 goto out_unlock;
1822 }
1823
1824 if (pid == 0) { /* child */
1825 struct lxc_storage *bdev = NULL;
1826
1827 bdev = do_storage_create(c, bdevtype, specs);
1828 if (!bdev) {
1829 ERROR("Failed to create %s storage for %s",
1830 bdevtype ? bdevtype : "(none)", c->name);
1831 _exit(EXIT_FAILURE);
1832 }
1833
1834 /* Save config file again to store the new rootfs location. */
1835 if (!do_lxcapi_save_config(c, NULL)) {
1836 ERROR("Failed to save initial config for %s", c->name);
1837 /* Parent task won't see the storage driver in the
1838 * config so we delete it.
1839 */
1840 bdev->ops->umount(bdev);
1841 bdev->ops->destroy(bdev);
1842 _exit(EXIT_FAILURE);
1843 }
1844 _exit(EXIT_SUCCESS);
1845 }
1846 if (wait_for_pid(pid) != 0)
1847 goto out_unlock;
1848
1849 /* Reload config to get the rootfs. */
1850 lxc_conf_free(c->lxc_conf);
1851 c->lxc_conf = NULL;
1852 if (!load_config_locked(c, c->configfile))
1853 goto out_unlock;
1854
1855 if (!create_run_template(c, tpath, !!(flags & LXC_CREATE_QUIET), argv))
1856 goto out_unlock;
1857
1858 /* Now clear out the lxc_conf we have, reload from the created
1859 * container.
1860 */
1861 do_lxcapi_clear_config(c);
1862
1863 if (t) {
1864 if (!prepend_lxc_header(c->configfile, tpath, argv)) {
1865 ERROR("Failed to prepend header to config file");
1866 goto out_unlock;
1867 }
1868 }
1869 ret = load_config_locked(c, c->configfile);
1870
1871 out_unlock:
1872 umask(mask);
1873 if (partial_fd >= 0)
1874 remove_partial(c, partial_fd);
1875 out:
1876 if (!ret)
1877 container_destroy(c, NULL);
1878 free_tpath:
1879 free(tpath);
1880 return ret;
1881 }
1882
1883 static bool lxcapi_create(struct lxc_container *c, const char *t,
1884 const char *bdevtype, struct bdev_specs *specs,
1885 int flags, char *const argv[])
1886 {
1887 bool ret;
1888 current_config = c ? c->lxc_conf : NULL;
1889 ret = do_lxcapi_create(c, t, bdevtype, specs, flags, argv);
1890 current_config = NULL;
1891 return ret;
1892 }
1893
1894 static bool do_lxcapi_reboot(struct lxc_container *c)
1895 {
1896 int ret;
1897 pid_t pid;
1898 int rebootsignal = SIGINT;
1899
1900 if (!c)
1901 return false;
1902
1903 if (!do_lxcapi_is_running(c))
1904 return false;
1905
1906 pid = do_lxcapi_init_pid(c);
1907 if (pid <= 0)
1908 return false;
1909
1910 if (c->lxc_conf && c->lxc_conf->rebootsignal)
1911 rebootsignal = c->lxc_conf->rebootsignal;
1912
1913 ret = kill(pid, rebootsignal);
1914 if (ret < 0) {
1915 WARN("Failed to send signal %d to pid %d", rebootsignal, pid);
1916 return false;
1917 }
1918
1919 return true;
1920 }
1921
1922 WRAP_API(bool, lxcapi_reboot)
1923
1924 static bool do_lxcapi_reboot2(struct lxc_container *c, int timeout)
1925 {
1926 int killret, ret;
1927 pid_t pid;
1928 int rebootsignal = SIGINT, state_client_fd = -1;
1929 lxc_state_t states[MAX_STATE] = {0};
1930
1931 if (!c)
1932 return false;
1933
1934 if (!do_lxcapi_is_running(c))
1935 return true;
1936
1937 pid = do_lxcapi_init_pid(c);
1938 if (pid <= 0)
1939 return true;
1940
1941 if (c->lxc_conf && c->lxc_conf->rebootsignal)
1942 rebootsignal = c->lxc_conf->rebootsignal;
1943
1944 /* Add a new state client before sending the shutdown signal so that we
1945 * don't miss a state.
1946 */
1947 if (timeout != 0) {
1948 states[RUNNING] = 2;
1949 ret = lxc_cmd_add_state_client(c->name, c->config_path, states,
1950 &state_client_fd);
1951 if (ret < 0)
1952 return false;
1953
1954 if (state_client_fd < 0)
1955 return false;
1956
1957 if (ret == RUNNING)
1958 return true;
1959
1960 if (ret < MAX_STATE)
1961 return false;
1962 }
1963
1964 /* Send reboot signal to container. */
1965 killret = kill(pid, rebootsignal);
1966 if (killret < 0) {
1967 if (state_client_fd >= 0)
1968 close(state_client_fd);
1969 WARN("Failed to send signal %d to pid %d", rebootsignal, pid);
1970 return false;
1971 }
1972 TRACE("Sent signal %d to pid %d", rebootsignal, pid);
1973
1974 if (timeout == 0)
1975 return true;
1976
1977 ret = lxc_cmd_sock_rcv_state(state_client_fd, timeout);
1978 close(state_client_fd);
1979 if (ret < 0)
1980 return false;
1981
1982 TRACE("Received state \"%s\"", lxc_state2str(ret));
1983 if (ret != RUNNING)
1984 return false;
1985
1986 return true;
1987 }
1988
1989 WRAP_API_1(bool, lxcapi_reboot2, int)
1990
1991 static bool do_lxcapi_shutdown(struct lxc_container *c, int timeout)
1992 {
1993 int killret, ret;
1994 pid_t pid;
1995 int haltsignal = SIGPWR, state_client_fd = -EBADF;
1996 lxc_state_t states[MAX_STATE] = {0};
1997
1998 if (!c)
1999 return false;
2000
2001 if (!do_lxcapi_is_running(c))
2002 return true;
2003
2004 pid = do_lxcapi_init_pid(c);
2005 if (pid <= 0)
2006 return true;
2007
2008 /* Detect whether we should send SIGRTMIN + 3 (e.g. systemd). */
2009 if (c->lxc_conf && c->lxc_conf->haltsignal)
2010 haltsignal = c->lxc_conf->haltsignal;
2011 else if (task_blocks_signal(pid, (SIGRTMIN + 3)))
2012 haltsignal = (SIGRTMIN + 3);
2013
2014 /* Add a new state client before sending the shutdown signal so that we
2015 * don't miss a state.
2016 */
2017 if (timeout != 0) {
2018 states[STOPPED] = 1;
2019 ret = lxc_cmd_add_state_client(c->name, c->config_path, states,
2020 &state_client_fd);
2021 if (ret < 0)
2022 return false;
2023
2024 if (state_client_fd < 0)
2025 return false;
2026
2027 if (ret == STOPPED)
2028 return true;
2029
2030 if (ret < MAX_STATE)
2031 return false;
2032 }
2033
2034 /* Send shutdown signal to container. */
2035 killret = kill(pid, haltsignal);
2036 if (killret < 0) {
2037 if (state_client_fd >= 0)
2038 close(state_client_fd);
2039 WARN("Failed to send signal %d to pid %d", haltsignal, pid);
2040 return false;
2041 }
2042 TRACE("Sent signal %d to pid %d", haltsignal, pid);
2043
2044 if (timeout == 0)
2045 return true;
2046
2047 ret = lxc_cmd_sock_rcv_state(state_client_fd, timeout);
2048 close(state_client_fd);
2049 if (ret < 0)
2050 return false;
2051
2052 TRACE("Received state \"%s\"", lxc_state2str(ret));
2053 if (ret != STOPPED)
2054 return false;
2055
2056 return true;
2057 }
2058
2059 WRAP_API_1(bool, lxcapi_shutdown, int)
2060
2061 static bool lxcapi_createl(struct lxc_container *c, const char *t,
2062 const char *bdevtype, struct bdev_specs *specs, int flags, ...)
2063 {
2064 bool bret = false;
2065 char **args = NULL;
2066 va_list ap;
2067
2068 if (!c)
2069 return false;
2070
2071 current_config = c->lxc_conf;
2072
2073 /*
2074 * since we're going to wait for create to finish, I don't think we
2075 * need to get a copy of the arguments.
2076 */
2077 va_start(ap, flags);
2078 args = lxc_va_arg_list_to_argv(ap, 0, 0);
2079 va_end(ap);
2080 if (!args) {
2081 ERROR("Failed to allocate memory");
2082 goto out;
2083 }
2084
2085 bret = do_lxcapi_create(c, t, bdevtype, specs, flags, args);
2086
2087 out:
2088 free(args);
2089 current_config = NULL;
2090 return bret;
2091 }
2092
2093 static void do_clear_unexp_config_line(struct lxc_conf *conf, const char *key)
2094 {
2095 if (!strcmp(key, "lxc.cgroup"))
2096 return clear_unexp_config_line(conf, key, true);
2097
2098 if (!strcmp(key, "lxc.network"))
2099 return clear_unexp_config_line(conf, key, true);
2100
2101 if (!strcmp(key, "lxc.net"))
2102 return clear_unexp_config_line(conf, key, true);
2103
2104 /* Clear a network with a specific index. */
2105 if (!strncmp(key, "lxc.net.", 8)) {
2106 int ret;
2107 const char *idx;
2108
2109 idx = key + 8;
2110 ret = lxc_safe_uint(idx, &(unsigned int){0});
2111 if (!ret)
2112 return clear_unexp_config_line(conf, key, true);
2113 }
2114
2115 if (!strcmp(key, "lxc.hook"))
2116 return clear_unexp_config_line(conf, key, true);
2117
2118 return clear_unexp_config_line(conf, key, false);
2119 }
2120
2121 static bool do_lxcapi_clear_config_item(struct lxc_container *c,
2122 const char *key)
2123 {
2124 int ret = 1;
2125 struct lxc_config_t *config;
2126
2127 if (!c || !c->lxc_conf)
2128 return false;
2129
2130 if (container_mem_lock(c))
2131 return false;
2132
2133 config = lxc_get_config(key);
2134 /* Verify that the config key exists and that it has a callback
2135 * implemented.
2136 */
2137 if (config && config->clr)
2138 ret = config->clr(key, c->lxc_conf, NULL);
2139 if (!ret)
2140 do_clear_unexp_config_line(c->lxc_conf, key);
2141
2142 container_mem_unlock(c);
2143 return ret == 0;
2144 }
2145
2146 WRAP_API_1(bool, lxcapi_clear_config_item, const char *)
2147
2148 static inline bool enter_net_ns(struct lxc_container *c)
2149 {
2150 pid_t pid = do_lxcapi_init_pid(c);
2151
2152 if ((geteuid() != 0 || (c->lxc_conf && !lxc_list_empty(&c->lxc_conf->id_map))) && access("/proc/self/ns/user", F_OK) == 0) {
2153 if (!switch_to_ns(pid, "user"))
2154 return false;
2155 }
2156 return switch_to_ns(pid, "net");
2157 }
2158
2159 /* Used by qsort and bsearch functions for comparing names. */
2160 static inline int string_cmp(char **first, char **second)
2161 {
2162 return strcmp(*first, *second);
2163 }
2164
2165 /* Used by qsort and bsearch functions for comparing container names. */
2166 static inline int container_cmp(struct lxc_container **first,
2167 struct lxc_container **second)
2168 {
2169 return strcmp((*first)->name, (*second)->name);
2170 }
2171
2172 static bool add_to_array(char ***names, char *cname, int pos)
2173 {
2174 char **newnames = realloc(*names, (pos+1) * sizeof(char *));
2175 if (!newnames) {
2176 ERROR("Out of memory");
2177 return false;
2178 }
2179
2180 *names = newnames;
2181 newnames[pos] = strdup(cname);
2182 if (!newnames[pos])
2183 return false;
2184
2185 /* Sort the arrray as we will use binary search on it. */
2186 qsort(newnames, pos + 1, sizeof(char *),
2187 (int (*)(const void *, const void *))string_cmp);
2188
2189 return true;
2190 }
2191
2192 static bool add_to_clist(struct lxc_container ***list, struct lxc_container *c,
2193 int pos, bool sort)
2194 {
2195 struct lxc_container **newlist = realloc(*list, (pos + 1) * sizeof(struct lxc_container *));
2196 if (!newlist) {
2197 ERROR("Out of memory");
2198 return false;
2199 }
2200
2201 *list = newlist;
2202 newlist[pos] = c;
2203
2204 /* Sort the arrray as we will use binary search on it. */
2205 if (sort)
2206 qsort(newlist, pos + 1, sizeof(struct lxc_container *),
2207 (int (*)(const void *, const void *))container_cmp);
2208
2209 return true;
2210 }
2211
2212 static char** get_from_array(char ***names, char *cname, int size)
2213 {
2214 return (char **)bsearch(&cname, *names, size, sizeof(char *), (int (*)(const void *, const void *))string_cmp);
2215 }
2216
2217
2218 static bool array_contains(char ***names, char *cname, int size) {
2219 if(get_from_array(names, cname, size) != NULL)
2220 return true;
2221 return false;
2222 }
2223
2224 static bool remove_from_array(char ***names, char *cname, int size)
2225 {
2226 char **result = get_from_array(names, cname, size);
2227 if (result != NULL) {
2228 free(result);
2229 return true;
2230 }
2231 return false;
2232 }
2233
2234 static char ** do_lxcapi_get_interfaces(struct lxc_container *c)
2235 {
2236 pid_t pid;
2237 int i, count = 0, pipefd[2];
2238 char **interfaces = NULL;
2239 char interface[IFNAMSIZ];
2240
2241 if(pipe(pipefd) < 0) {
2242 SYSERROR("pipe failed");
2243 return NULL;
2244 }
2245
2246 pid = fork();
2247 if (pid < 0) {
2248 SYSERROR("failed to fork task to get interfaces information");
2249 close(pipefd[0]);
2250 close(pipefd[1]);
2251 return NULL;
2252 }
2253
2254 if (pid == 0) { /* child */
2255 int ret = 1, nbytes;
2256 struct ifaddrs *interfaceArray = NULL, *tempIfAddr = NULL;
2257
2258 /* close the read-end of the pipe */
2259 close(pipefd[0]);
2260
2261 if (!enter_net_ns(c)) {
2262 SYSERROR("failed to enter namespace");
2263 goto out;
2264 }
2265
2266 /* Grab the list of interfaces */
2267 if (getifaddrs(&interfaceArray)) {
2268 SYSERROR("failed to get interfaces list");
2269 goto out;
2270 }
2271
2272 /* Iterate through the interfaces */
2273 for (tempIfAddr = interfaceArray; tempIfAddr != NULL; tempIfAddr = tempIfAddr->ifa_next) {
2274 nbytes = write(pipefd[1], tempIfAddr->ifa_name, IFNAMSIZ);
2275 if (nbytes < 0) {
2276 ERROR("write failed");
2277 goto out;
2278 }
2279 count++;
2280 }
2281 ret = 0;
2282
2283 out:
2284 if (interfaceArray)
2285 freeifaddrs(interfaceArray);
2286
2287 /* close the write-end of the pipe, thus sending EOF to the reader */
2288 close(pipefd[1]);
2289 _exit(ret);
2290 }
2291
2292 /* close the write-end of the pipe */
2293 close(pipefd[1]);
2294
2295 while (read(pipefd[0], &interface, IFNAMSIZ) == IFNAMSIZ) {
2296 interface[IFNAMSIZ - 1] = '\0';
2297
2298 if (array_contains(&interfaces, interface, count))
2299 continue;
2300
2301 if(!add_to_array(&interfaces, interface, count))
2302 ERROR("Failed to add \"%s\" to array", interface);
2303
2304 count++;
2305 }
2306
2307 if (wait_for_pid(pid) != 0) {
2308 for(i=0;i<count;i++)
2309 free(interfaces[i]);
2310 free(interfaces);
2311 interfaces = NULL;
2312 }
2313
2314 /* close the read-end of the pipe */
2315 close(pipefd[0]);
2316
2317 /* Append NULL to the array */
2318 if(interfaces)
2319 interfaces = (char **)lxc_append_null_to_array((void **)interfaces, count);
2320
2321 return interfaces;
2322 }
2323
2324 WRAP_API(char **, lxcapi_get_interfaces)
2325
2326 static char** do_lxcapi_get_ips(struct lxc_container *c, const char* interface, const char* family, int scope)
2327 {
2328 pid_t pid;
2329 int i, count = 0, pipefd[2];
2330 char **addresses = NULL;
2331 char address[INET6_ADDRSTRLEN];
2332
2333 if(pipe(pipefd) < 0) {
2334 SYSERROR("pipe failed");
2335 return NULL;
2336 }
2337
2338 pid = fork();
2339 if (pid < 0) {
2340 SYSERROR("failed to fork task to get container ips");
2341 close(pipefd[0]);
2342 close(pipefd[1]);
2343 return NULL;
2344 }
2345
2346 if (pid == 0) { /* child */
2347 int ret = 1, nbytes;
2348 struct ifaddrs *interfaceArray = NULL, *tempIfAddr = NULL;
2349 char addressOutputBuffer[INET6_ADDRSTRLEN];
2350 void *tempAddrPtr = NULL;
2351 char *address = NULL;
2352
2353 /* close the read-end of the pipe */
2354 close(pipefd[0]);
2355
2356 if (!enter_net_ns(c)) {
2357 SYSERROR("failed to enter namespace");
2358 goto out;
2359 }
2360
2361 /* Grab the list of interfaces */
2362 if (getifaddrs(&interfaceArray)) {
2363 SYSERROR("failed to get interfaces list");
2364 goto out;
2365 }
2366
2367 /* Iterate through the interfaces */
2368 for (tempIfAddr = interfaceArray; tempIfAddr != NULL; tempIfAddr = tempIfAddr->ifa_next) {
2369 if (tempIfAddr->ifa_addr == NULL)
2370 continue;
2371
2372 if(tempIfAddr->ifa_addr->sa_family == AF_INET) {
2373 if (family && strcmp(family, "inet"))
2374 continue;
2375 tempAddrPtr = &((struct sockaddr_in *)tempIfAddr->ifa_addr)->sin_addr;
2376 }
2377 else {
2378 if (family && strcmp(family, "inet6"))
2379 continue;
2380
2381 if (((struct sockaddr_in6 *)tempIfAddr->ifa_addr)->sin6_scope_id != scope)
2382 continue;
2383
2384 tempAddrPtr = &((struct sockaddr_in6 *)tempIfAddr->ifa_addr)->sin6_addr;
2385 }
2386
2387 if (interface && strcmp(interface, tempIfAddr->ifa_name))
2388 continue;
2389 else if (!interface && strcmp("lo", tempIfAddr->ifa_name) == 0)
2390 continue;
2391
2392 address = (char *)inet_ntop(tempIfAddr->ifa_addr->sa_family,
2393 tempAddrPtr,
2394 addressOutputBuffer,
2395 sizeof(addressOutputBuffer));
2396 if (!address)
2397 continue;
2398
2399 nbytes = write(pipefd[1], address, INET6_ADDRSTRLEN);
2400 if (nbytes < 0) {
2401 ERROR("write failed");
2402 goto out;
2403 }
2404 count++;
2405 }
2406 ret = 0;
2407
2408 out:
2409 if(interfaceArray)
2410 freeifaddrs(interfaceArray);
2411
2412 /* close the write-end of the pipe, thus sending EOF to the reader */
2413 close(pipefd[1]);
2414 _exit(ret);
2415 }
2416
2417 /* close the write-end of the pipe */
2418 close(pipefd[1]);
2419
2420 while (read(pipefd[0], &address, INET6_ADDRSTRLEN) == INET6_ADDRSTRLEN) {
2421 if(!add_to_array(&addresses, address, count))
2422 ERROR("PARENT: add_to_array failed");
2423 count++;
2424 }
2425
2426 if (wait_for_pid(pid) != 0) {
2427 for(i=0;i<count;i++)
2428 free(addresses[i]);
2429 free(addresses);
2430 addresses = NULL;
2431 }
2432
2433 /* close the read-end of the pipe */
2434 close(pipefd[0]);
2435
2436 /* Append NULL to the array */
2437 if(addresses)
2438 addresses = (char **)lxc_append_null_to_array((void **)addresses, count);
2439
2440 return addresses;
2441 }
2442
2443 WRAP_API_3(char **, lxcapi_get_ips, const char *, const char *, int)
2444
2445 static int do_lxcapi_get_config_item(struct lxc_container *c, const char *key, char *retv, int inlen)
2446 {
2447 int ret = -1;
2448 struct lxc_config_t *config;
2449
2450 if (!c || !c->lxc_conf)
2451 return -1;
2452
2453 if (container_mem_lock(c))
2454 return -1;
2455
2456 config = lxc_get_config(key);
2457 /* Verify that the config key exists and that it has a callback
2458 * implemented.
2459 */
2460 if (config && config->get)
2461 ret = config->get(key, retv, inlen, c->lxc_conf, NULL);
2462
2463 container_mem_unlock(c);
2464 return ret;
2465 }
2466
2467 WRAP_API_3(int, lxcapi_get_config_item, const char *, char *, int)
2468
2469 static char* do_lxcapi_get_running_config_item(struct lxc_container *c, const char *key)
2470 {
2471 char *ret;
2472
2473 if (!c || !c->lxc_conf)
2474 return NULL;
2475 if (container_mem_lock(c))
2476 return NULL;
2477 ret = lxc_cmd_get_config_item(c->name, key, do_lxcapi_get_config_path(c));
2478 container_mem_unlock(c);
2479 return ret;
2480 }
2481
2482 WRAP_API_1(char *, lxcapi_get_running_config_item, const char *)
2483
2484 static int do_lxcapi_get_keys(struct lxc_container *c, const char *key, char *retv, int inlen)
2485 {
2486 int ret = -1;
2487
2488 /* List all config items. */
2489 if (!key)
2490 return lxc_list_config_items(retv, inlen);
2491
2492 if (!c || !c->lxc_conf)
2493 return -1;
2494
2495 if (container_mem_lock(c))
2496 return -1;
2497
2498 /* Support 'lxc.net.<idx>', i.e. 'lxc.net.0'
2499 * This is an intelligent result to show which keys are valid given the
2500 * type of nic it is.
2501 */
2502 if (strncmp(key, "lxc.net.", 8) == 0)
2503 ret = lxc_list_net(c->lxc_conf, key, retv, inlen);
2504 else
2505 ret = lxc_list_subkeys(c->lxc_conf, key, retv, inlen);
2506
2507 container_mem_unlock(c);
2508 return ret;
2509 }
2510
2511 WRAP_API_3(int, lxcapi_get_keys, const char *, char *, int)
2512
2513 static bool do_lxcapi_save_config(struct lxc_container *c, const char *alt_file)
2514 {
2515 int fd, lret;
2516 bool ret = false, need_disklock = false;
2517
2518 if (!alt_file)
2519 alt_file = c->configfile;
2520 if (!alt_file)
2521 return false;
2522
2523 /* If we haven't yet loaded a config, load the stock config. */
2524 if (!c->lxc_conf) {
2525 if (!do_lxcapi_load_config(c, lxc_global_config_value("lxc.default_config"))) {
2526 ERROR("Error loading default configuration file %s "
2527 "while saving %s",
2528 lxc_global_config_value("lxc.default_config"),
2529 c->name);
2530 return false;
2531 }
2532 }
2533
2534 if (!create_container_dir(c))
2535 return false;
2536
2537 /* If we're writing to the container's config file, take the disk lock.
2538 * Otherwise just take the memlock to protect the struct lxc_container
2539 * while we're traversing it.
2540 */
2541 if (strcmp(c->configfile, alt_file) == 0)
2542 need_disklock = true;
2543
2544 if (need_disklock)
2545 lret = container_disk_lock(c);
2546 else
2547 lret = container_mem_lock(c);
2548 if (lret)
2549 return false;
2550
2551 fd = open(alt_file, O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC,
2552 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
2553 if (fd < 0)
2554 goto on_error;
2555
2556 lret = write_config(fd, c->lxc_conf);
2557 close(fd);
2558 if (lret < 0)
2559 goto on_error;
2560
2561 ret = true;
2562
2563 on_error:
2564 if (need_disklock)
2565 container_disk_unlock(c);
2566 else
2567 container_mem_unlock(c);
2568
2569 return ret;
2570 }
2571
2572 WRAP_API_1(bool, lxcapi_save_config, const char *)
2573
2574
2575 static bool mod_rdep(struct lxc_container *c0, struct lxc_container *c, bool inc)
2576 {
2577 FILE *f1;
2578 struct stat fbuf;
2579 void *buf = NULL;
2580 char *del = NULL;
2581 char path[MAXPATHLEN];
2582 char newpath[MAXPATHLEN];
2583 int fd, ret, n = 0, v = 0;
2584 bool bret = false;
2585 size_t len = 0, bytes = 0;
2586
2587 if (container_disk_lock(c0))
2588 return false;
2589
2590 ret = snprintf(path, MAXPATHLEN, "%s/%s/lxc_snapshots", c0->config_path, c0->name);
2591 if (ret < 0 || ret > MAXPATHLEN)
2592 goto out;
2593 ret = snprintf(newpath, MAXPATHLEN, "%s\n%s\n", c->config_path, c->name);
2594 if (ret < 0 || ret > MAXPATHLEN)
2595 goto out;
2596
2597 /* If we find an lxc-snapshot file using the old format only listing the
2598 * number of snapshots we will keep using it. */
2599 f1 = fopen(path, "r");
2600 if (f1) {
2601 n = fscanf(f1, "%d", &v);
2602 fclose(f1);
2603 if (n == 1 && v == 0) {
2604 remove(path);
2605 n = 0;
2606 }
2607 }
2608 if (n == 1) {
2609 v += inc ? 1 : -1;
2610 f1 = fopen(path, "w");
2611 if (!f1)
2612 goto out;
2613 if (fprintf(f1, "%d\n", v) < 0) {
2614 ERROR("Error writing new snapshots value");
2615 fclose(f1);
2616 goto out;
2617 }
2618 ret = fclose(f1);
2619 if (ret != 0) {
2620 SYSERROR("Error writing to or closing snapshots file");
2621 goto out;
2622 }
2623 } else {
2624 /* Here we know that we have or can use an lxc-snapshot file
2625 * using the new format. */
2626 if (inc) {
2627 f1 = fopen(path, "a");
2628 if (!f1)
2629 goto out;
2630
2631 if (fprintf(f1, "%s", newpath) < 0) {
2632 ERROR("Error writing new snapshots entry");
2633 ret = fclose(f1);
2634 if (ret != 0)
2635 SYSERROR("Error writing to or closing snapshots file");
2636 goto out;
2637 }
2638
2639 ret = fclose(f1);
2640 if (ret != 0) {
2641 SYSERROR("Error writing to or closing snapshots file");
2642 goto out;
2643 }
2644 } else if (!inc) {
2645 if ((fd = open(path, O_RDWR | O_CLOEXEC)) < 0)
2646 goto out;
2647
2648 if (fstat(fd, &fbuf) < 0) {
2649 close(fd);
2650 goto out;
2651 }
2652
2653 if (fbuf.st_size != 0) {
2654
2655 buf = lxc_strmmap(NULL, fbuf.st_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
2656 if (buf == MAP_FAILED) {
2657 SYSERROR("Failed to create mapping %s", path);
2658 close(fd);
2659 goto out;
2660 }
2661
2662 len = strlen(newpath);
2663 while ((del = strstr((char *)buf, newpath))) {
2664 memmove(del, del + len, strlen(del) - len + 1);
2665 bytes += len;
2666 }
2667
2668 lxc_strmunmap(buf, fbuf.st_size);
2669 if (ftruncate(fd, fbuf.st_size - bytes) < 0) {
2670 SYSERROR("Failed to truncate file %s", path);
2671 close(fd);
2672 goto out;
2673 }
2674 }
2675 close(fd);
2676 }
2677
2678 /* If the lxc-snapshot file is empty, remove it. */
2679 if (stat(path, &fbuf) < 0)
2680 goto out;
2681 if (!fbuf.st_size) {
2682 remove(path);
2683 }
2684 }
2685
2686 bret = true;
2687
2688 out:
2689 container_disk_unlock(c0);
2690 return bret;
2691 }
2692
2693 void mod_all_rdeps(struct lxc_container *c, bool inc)
2694 {
2695 struct lxc_container *p;
2696 char *lxcpath = NULL, *lxcname = NULL, path[MAXPATHLEN];
2697 size_t pathlen = 0, namelen = 0;
2698 FILE *f;
2699 int ret;
2700
2701 ret = snprintf(path, MAXPATHLEN, "%s/%s/lxc_rdepends",
2702 c->config_path, c->name);
2703 if (ret < 0 || ret >= MAXPATHLEN) {
2704 ERROR("Path name too long");
2705 return;
2706 }
2707 f = fopen(path, "r");
2708 if (f == NULL)
2709 return;
2710 while (getline(&lxcpath, &pathlen, f) != -1) {
2711 if (getline(&lxcname, &namelen, f) == -1) {
2712 ERROR("badly formatted file %s", path);
2713 goto out;
2714 }
2715
2716 remove_trailing_newlines(lxcpath);
2717 remove_trailing_newlines(lxcname);
2718
2719 if ((p = lxc_container_new(lxcname, lxcpath)) == NULL) {
2720 ERROR("Unable to find dependent container %s:%s",
2721 lxcpath, lxcname);
2722 continue;
2723 }
2724 if (!mod_rdep(p, c, inc))
2725 ERROR("Failed to update snapshots file for %s:%s",
2726 lxcpath, lxcname);
2727 lxc_container_put(p);
2728 }
2729 out:
2730 free(lxcpath);
2731 free(lxcname);
2732 fclose(f);
2733 }
2734
2735 static bool has_fs_snapshots(struct lxc_container *c)
2736 {
2737 FILE *f;
2738 char path[MAXPATHLEN];
2739 int ret, v;
2740 struct stat fbuf;
2741 bool bret = false;
2742
2743 ret = snprintf(path, MAXPATHLEN, "%s/%s/lxc_snapshots", c->config_path,
2744 c->name);
2745 if (ret < 0 || ret > MAXPATHLEN)
2746 goto out;
2747 /* If the file doesn't exist there are no snapshots. */
2748 if (stat(path, &fbuf) < 0)
2749 goto out;
2750 v = fbuf.st_size;
2751 if (v != 0) {
2752 f = fopen(path, "r");
2753 if (!f)
2754 goto out;
2755 ret = fscanf(f, "%d", &v);
2756 fclose(f);
2757 /* TODO: Figure out what to do with the return value of fscanf. */
2758 if (ret != 1)
2759 INFO("Container uses new lxc-snapshots format %s", path);
2760 }
2761 bret = v != 0;
2762
2763 out:
2764 return bret;
2765 }
2766
2767 static bool has_snapshots(struct lxc_container *c)
2768 {
2769 char path[MAXPATHLEN];
2770 struct dirent *direntp;
2771 int count=0;
2772 DIR *dir;
2773
2774 if (!get_snappath_dir(c, path))
2775 return false;
2776 dir = opendir(path);
2777 if (!dir)
2778 return false;
2779 while ((direntp = readdir(dir))) {
2780 if (!strcmp(direntp->d_name, "."))
2781 continue;
2782
2783 if (!strcmp(direntp->d_name, ".."))
2784 continue;
2785 count++;
2786 break;
2787 }
2788 closedir(dir);
2789 return count > 0;
2790 }
2791
2792 static bool do_destroy_container(struct lxc_conf *conf) {
2793 int ret;
2794
2795 if (am_guest_unpriv()) {
2796 ret = userns_exec_full(conf, storage_destroy_wrapper, conf,
2797 "storage_destroy_wrapper");
2798 if (ret < 0)
2799 return false;
2800
2801 return true;
2802 }
2803
2804 return storage_destroy(conf);
2805 }
2806
2807 static int lxc_rmdir_onedev_wrapper(void *data)
2808 {
2809 char *arg = (char *) data;
2810 return lxc_rmdir_onedev(arg, "snaps");
2811 }
2812
2813 static int lxc_unlink_exec_wrapper(void *data)
2814 {
2815 char *arg = data;
2816 return unlink(arg);
2817 }
2818
2819 static bool container_destroy(struct lxc_container *c,
2820 struct lxc_storage *storage)
2821 {
2822 const char *p1;
2823 size_t len;
2824 struct lxc_conf *conf;
2825 char *path = NULL;
2826 bool bret = false;
2827 int ret = 0;
2828
2829 if (!c || !do_lxcapi_is_defined(c))
2830 return false;
2831
2832 conf = c->lxc_conf;
2833 if (container_disk_lock(c))
2834 return false;
2835
2836 if (!is_stopped(c)) {
2837 /* We should queue some sort of error - in c->error_string? */
2838 ERROR("container %s is not stopped", c->name);
2839 goto out;
2840 }
2841
2842 if (conf && !lxc_list_empty(&conf->hooks[LXCHOOK_DESTROY])) {
2843 /* Start of environment variable setup for hooks */
2844 if (setenv("LXC_NAME", c->name, 1))
2845 SYSERROR("Failed to set environment variable for container name");
2846
2847 if (conf->rcfile && setenv("LXC_CONFIG_FILE", conf->rcfile, 1))
2848 SYSERROR("Failed to set environment variable for config path");
2849
2850 if (conf->rootfs.mount && setenv("LXC_ROOTFS_MOUNT", conf->rootfs.mount, 1))
2851 SYSERROR("Failed to set environment variable for rootfs mount");
2852
2853 if (conf->rootfs.path && setenv("LXC_ROOTFS_PATH", conf->rootfs.path, 1))
2854 SYSERROR("Failed to set environment variable for rootfs mount");
2855
2856 if (conf->console.path && setenv("LXC_CONSOLE", conf->console.path, 1))
2857 SYSERROR("Failed to set environment variable for console path");
2858
2859 if (conf->console.log_path && setenv("LXC_CONSOLE_LOGPATH", conf->console.log_path, 1))
2860 SYSERROR("Failed to set environment variable for console log");
2861 /* End of environment variable setup for hooks */
2862
2863 if (run_lxc_hooks(c->name, "destroy", conf, NULL)) {
2864 ERROR("Failed to execute clone hook for \"%s\"", c->name);
2865 goto out;
2866 }
2867 }
2868
2869 if (current_config && conf == current_config) {
2870 current_config = NULL;
2871 if (conf->logfd != -1) {
2872 close(conf->logfd);
2873 conf->logfd = -1;
2874 }
2875 }
2876
2877 if (conf && conf->rootfs.path && conf->rootfs.mount) {
2878 if (!do_destroy_container(conf)) {
2879 ERROR("Error destroying rootfs for %s", c->name);
2880 goto out;
2881 }
2882 INFO("Destroyed rootfs for %s", c->name);
2883 }
2884
2885 mod_all_rdeps(c, false);
2886
2887 p1 = do_lxcapi_get_config_path(c);
2888 /* strlen(p1)
2889 * +
2890 * /
2891 * +
2892 * strlen(c->name)
2893 * +
2894 * /
2895 * +
2896 * strlen("config") = 6
2897 * +
2898 * \0
2899 */
2900 len = strlen(p1) + 1 + strlen(c->name) + 1 + 6 + 1;
2901 path = malloc(len);
2902 if (!path) {
2903 ERROR("Failed to allocate memory");
2904 goto out;
2905 }
2906
2907 /* For an overlay container the rootfs is considered immutable and
2908 * cannot be removed when restoring from a snapshot.
2909 */
2910 if (storage && (!strcmp(storage->type, "overlay") ||
2911 !strcmp(storage->type, "overlayfs")) &&
2912 (storage->flags & LXC_STORAGE_INTERNAL_OVERLAY_RESTORE)) {
2913 ret = snprintf(path, len, "%s/%s/config", p1, c->name);
2914 if (ret < 0 || (size_t)ret >= len)
2915 goto out;
2916
2917 if (am_guest_unpriv())
2918 ret = userns_exec_1(conf, lxc_unlink_exec_wrapper, path,
2919 "lxc_unlink_exec_wrapper");
2920 else
2921 ret = unlink(path);
2922 if (ret < 0) {
2923 SYSERROR("Failed to destroy config file \"%s\" for \"%s\"",
2924 path, c->name);
2925 goto out;
2926 }
2927 INFO("Destroyed config file \"%s\" for \"%s\"", path, c->name);
2928
2929 bret = true;
2930 goto out;
2931 }
2932
2933 ret = snprintf(path, len, "%s/%s", p1, c->name);
2934 if (ret < 0 || (size_t)ret >= len)
2935 goto out;
2936 if (am_guest_unpriv())
2937 ret = userns_exec_full(conf, lxc_rmdir_onedev_wrapper, path,
2938 "lxc_rmdir_onedev_wrapper");
2939 else
2940 ret = lxc_rmdir_onedev(path, "snaps");
2941 if (ret < 0) {
2942 ERROR("Failed to destroy directory \"%s\" for \"%s\"", path,
2943 c->name);
2944 goto out;
2945 }
2946 INFO("Destroyed directory \"%s\" for \"%s\"", path, c->name);
2947
2948 bret = true;
2949
2950 out:
2951 if (path)
2952 free(path);
2953 container_disk_unlock(c);
2954 return bret;
2955 }
2956
2957 static bool do_lxcapi_destroy(struct lxc_container *c)
2958 {
2959 if (!c || !lxcapi_is_defined(c))
2960 return false;
2961
2962 if (has_snapshots(c)) {
2963 ERROR("Container %s has snapshots; not removing", c->name);
2964 return false;
2965 }
2966
2967 if (has_fs_snapshots(c)) {
2968 ERROR("container %s has snapshots on its rootfs", c->name);
2969 return false;
2970 }
2971
2972 return container_destroy(c, NULL);
2973 }
2974
2975 WRAP_API(bool, lxcapi_destroy)
2976
2977 static bool do_lxcapi_destroy_with_snapshots(struct lxc_container *c)
2978 {
2979 if (!c || !lxcapi_is_defined(c))
2980 return false;
2981 if (!lxcapi_snapshot_destroy_all(c)) {
2982 ERROR("Error deleting all snapshots");
2983 return false;
2984 }
2985 return lxcapi_destroy(c);
2986 }
2987
2988 WRAP_API(bool, lxcapi_destroy_with_snapshots)
2989
2990 int lxc_set_config_item_locked(struct lxc_conf *conf, const char *key,
2991 const char *v)
2992 {
2993 int ret;
2994 struct lxc_config_t *config;
2995 bool bret = true;
2996
2997 config = lxc_get_config(key);
2998 if (!config)
2999 return -EINVAL;
3000
3001 ret = config->set(key, v, conf, NULL);
3002 if (ret < 0)
3003 return -EINVAL;
3004
3005 if (lxc_config_value_empty(v))
3006 do_clear_unexp_config_line(conf, key);
3007 else
3008 bret = do_append_unexp_config_line(conf, key, v);
3009 if (!bret)
3010 return -ENOMEM;
3011
3012 return 0;
3013 }
3014
3015 static bool do_set_config_item_locked(struct lxc_container *c, const char *key,
3016 const char *v)
3017 {
3018 int ret;
3019
3020 if (!c->lxc_conf)
3021 c->lxc_conf = lxc_conf_init();
3022
3023 if (!c->lxc_conf)
3024 return false;
3025
3026 ret = lxc_set_config_item_locked(c->lxc_conf, key, v);
3027 if (ret < 0)
3028 return false;
3029
3030 return true;
3031 }
3032
3033 static bool do_lxcapi_set_config_item(struct lxc_container *c, const char *key, const char *v)
3034 {
3035 bool b = false;
3036
3037 if (!c)
3038 return false;
3039
3040 if (container_mem_lock(c))
3041 return false;
3042
3043 b = do_set_config_item_locked(c, key, v);
3044
3045 container_mem_unlock(c);
3046 return b;
3047 }
3048
3049 WRAP_API_2(bool, lxcapi_set_config_item, const char *, const char *)
3050
3051 static char *lxcapi_config_file_name(struct lxc_container *c)
3052 {
3053 if (!c || !c->configfile)
3054 return NULL;
3055 return strdup(c->configfile);
3056 }
3057
3058 static const char *lxcapi_get_config_path(struct lxc_container *c)
3059 {
3060 if (!c || !c->config_path)
3061 return NULL;
3062 return (const char *)(c->config_path);
3063 }
3064
3065 /*
3066 * not for export
3067 * Just recalculate the c->configfile based on the
3068 * c->config_path, which must be set.
3069 * The lxc_container must be locked or not yet public.
3070 */
3071 static bool set_config_filename(struct lxc_container *c)
3072 {
3073 char *newpath;
3074 int len, ret;
3075
3076 if (!c->config_path)
3077 return false;
3078
3079 /* $lxc_path + "/" + c->name + "/" + "config" + '\0' */
3080 len = strlen(c->config_path) + strlen(c->name) + strlen("config") + 3;
3081 newpath = malloc(len);
3082 if (!newpath)
3083 return false;
3084
3085 ret = snprintf(newpath, len, "%s/%s/config", c->config_path, c->name);
3086 if (ret < 0 || ret >= len) {
3087 fprintf(stderr, "Error printing out config file name\n");
3088 free(newpath);
3089 return false;
3090 }
3091
3092 free(c->configfile);
3093 c->configfile = newpath;
3094
3095 return true;
3096 }
3097
3098 static bool do_lxcapi_set_config_path(struct lxc_container *c, const char *path)
3099 {
3100 char *p;
3101 bool b = false;
3102 char *oldpath = NULL;
3103
3104 if (!c)
3105 return b;
3106
3107 if (container_mem_lock(c))
3108 return b;
3109
3110 p = strdup(path);
3111 if (!p) {
3112 ERROR("Out of memory setting new lxc path");
3113 goto err;
3114 }
3115
3116 b = true;
3117 if (c->config_path)
3118 oldpath = c->config_path;
3119 c->config_path = p;
3120
3121 /* Since we've changed the config path, we have to change the
3122 * config file name too */
3123 if (!set_config_filename(c)) {
3124 ERROR("Out of memory setting new config filename");
3125 b = false;
3126 free(c->config_path);
3127 c->config_path = oldpath;
3128 oldpath = NULL;
3129 }
3130 err:
3131 free(oldpath);
3132 container_mem_unlock(c);
3133 return b;
3134 }
3135
3136 WRAP_API_1(bool, lxcapi_set_config_path, const char *)
3137
3138 static bool do_lxcapi_set_cgroup_item(struct lxc_container *c, const char *subsys, const char *value)
3139 {
3140 int ret;
3141 struct cgroup_ops *cgroup_ops;
3142
3143 if (!c)
3144 return false;
3145
3146 if (is_stopped(c))
3147 return false;
3148
3149 cgroup_ops = cgroup_init(NULL);
3150 if (!cgroup_ops)
3151 return false;
3152
3153 if (container_disk_lock(c))
3154 return false;
3155
3156 ret = cgroup_ops->set(cgroup_ops, subsys, value, c->name, c->config_path);
3157
3158 container_disk_unlock(c);
3159
3160 cgroup_exit(cgroup_ops);
3161
3162 return ret == 0;
3163 }
3164
3165 WRAP_API_2(bool, lxcapi_set_cgroup_item, const char *, const char *)
3166
3167 static int do_lxcapi_get_cgroup_item(struct lxc_container *c, const char *subsys, char *retv, int inlen)
3168 {
3169 int ret;
3170 struct cgroup_ops *cgroup_ops;
3171
3172 if (!c)
3173 return -1;
3174
3175 if (is_stopped(c))
3176 return -1;
3177
3178 cgroup_ops = cgroup_init(NULL);
3179 if (!cgroup_ops)
3180 return -1;
3181
3182 if (container_disk_lock(c))
3183 return -1;
3184
3185 ret = cgroup_ops->get(cgroup_ops, subsys, retv, inlen, c->name,
3186 c->config_path);
3187
3188 container_disk_unlock(c);
3189
3190 cgroup_exit(cgroup_ops);
3191
3192 return ret;
3193 }
3194
3195 WRAP_API_3(int, lxcapi_get_cgroup_item, const char *, char *, int)
3196
3197 const char *lxc_get_global_config_item(const char *key)
3198 {
3199 return lxc_global_config_value(key);
3200 }
3201
3202 const char *lxc_get_version(void)
3203 {
3204 return LXC_VERSION;
3205 }
3206
3207 static int copy_file(const char *old, const char *new)
3208 {
3209 int in, out;
3210 ssize_t len, ret;
3211 char buf[8096];
3212 struct stat sbuf;
3213
3214 if (file_exists(new)) {
3215 ERROR("copy destination %s exists", new);
3216 return -1;
3217 }
3218 ret = stat(old, &sbuf);
3219 if (ret < 0) {
3220 INFO("Error stat'ing %s", old);
3221 return -1;
3222 }
3223
3224 in = open(old, O_RDONLY);
3225 if (in < 0) {
3226 SYSERROR("Error opening original file %s", old);
3227 return -1;
3228 }
3229 out = open(new, O_CREAT | O_EXCL | O_WRONLY, 0644);
3230 if (out < 0) {
3231 SYSERROR("Error opening new file %s", new);
3232 close(in);
3233 return -1;
3234 }
3235
3236 while (1) {
3237 len = read(in, buf, 8096);
3238 if (len < 0) {
3239 SYSERROR("Error reading old file %s", old);
3240 goto err;
3241 }
3242 if (len == 0)
3243 break;
3244 ret = write(out, buf, len);
3245 if (ret < len) { /* should we retry? */
3246 SYSERROR("Error: write to new file %s was interrupted", new);
3247 goto err;
3248 }
3249 }
3250 close(in);
3251 close(out);
3252
3253 /* We set mode, but not owner/group. */
3254 ret = chmod(new, sbuf.st_mode);
3255 if (ret) {
3256 SYSERROR("Error setting mode on %s", new);
3257 return -1;
3258 }
3259
3260 return 0;
3261
3262 err:
3263 close(in);
3264 close(out);
3265 return -1;
3266 }
3267
3268 static int copyhooks(struct lxc_container *oldc, struct lxc_container *c)
3269 {
3270 int i, len, ret;
3271 struct lxc_list *it;
3272 char *cpath;
3273
3274 len = strlen(oldc->config_path) + strlen(oldc->name) + 3;
3275 cpath = alloca(len);
3276 ret = snprintf(cpath, len, "%s/%s/", oldc->config_path, oldc->name);
3277 if (ret < 0 || ret >= len)
3278 return -1;
3279
3280 for (i=0; i<NUM_LXC_HOOKS; i++) {
3281 lxc_list_for_each(it, &c->lxc_conf->hooks[i]) {
3282 char *hookname = it->elem;
3283 char *fname = strrchr(hookname, '/');
3284 char tmppath[MAXPATHLEN];
3285 if (!fname) /* relative path - we don't support, but maybe we should */
3286 return 0;
3287 if (strncmp(hookname, cpath, len - 1) != 0) {
3288 /* this hook is public - ignore */
3289 continue;
3290 }
3291 /* copy the script, and change the entry in confile */
3292 ret = snprintf(tmppath, MAXPATHLEN, "%s/%s/%s",
3293 c->config_path, c->name, fname+1);
3294 if (ret < 0 || ret >= MAXPATHLEN)
3295 return -1;
3296 ret = copy_file(it->elem, tmppath);
3297 if (ret < 0)
3298 return -1;
3299 free(it->elem);
3300 it->elem = strdup(tmppath);
3301 if (!it->elem) {
3302 ERROR("out of memory copying hook path");
3303 return -1;
3304 }
3305 }
3306 }
3307
3308 if (!clone_update_unexp_hooks(c->lxc_conf, oldc->config_path,
3309 c->config_path, oldc->name, c->name)) {
3310 ERROR("Error saving new hooks in clone");
3311 return -1;
3312 }
3313 do_lxcapi_save_config(c, NULL);
3314 return 0;
3315 }
3316
3317
3318 static int copy_fstab(struct lxc_container *oldc, struct lxc_container *c)
3319 {
3320 char newpath[MAXPATHLEN];
3321 char *oldpath = oldc->lxc_conf->fstab;
3322 int ret;
3323
3324 if (!oldpath)
3325 return 0;
3326
3327 clear_unexp_config_line(c->lxc_conf, "lxc.mount.fstab", false);
3328
3329 char *p = strrchr(oldpath, '/');
3330 if (!p)
3331 return -1;
3332 ret = snprintf(newpath, MAXPATHLEN, "%s/%s%s",
3333 c->config_path, c->name, p);
3334 if (ret < 0 || ret >= MAXPATHLEN) {
3335 ERROR("error printing new path for %s", oldpath);
3336 return -1;
3337 }
3338 if (file_exists(newpath)) {
3339 ERROR("error: fstab file %s exists", newpath);
3340 return -1;
3341 }
3342
3343 if (copy_file(oldpath, newpath) < 0) {
3344 ERROR("error: copying %s to %s", oldpath, newpath);
3345 return -1;
3346 }
3347 free(c->lxc_conf->fstab);
3348 c->lxc_conf->fstab = strdup(newpath);
3349 if (!c->lxc_conf->fstab) {
3350 ERROR("error: allocating pathname");
3351 return -1;
3352 }
3353 if (!do_append_unexp_config_line(c->lxc_conf, "lxc.mount.fstab", newpath)) {
3354 ERROR("error saving new lxctab");
3355 return -1;
3356 }
3357
3358 return 0;
3359 }
3360
3361 static void copy_rdepends(struct lxc_container *c, struct lxc_container *c0)
3362 {
3363 char path0[MAXPATHLEN], path1[MAXPATHLEN];
3364 int ret;
3365
3366 ret = snprintf(path0, MAXPATHLEN, "%s/%s/lxc_rdepends", c0->config_path,
3367 c0->name);
3368 if (ret < 0 || ret >= MAXPATHLEN) {
3369 WARN("Error copying reverse dependencies");
3370 return;
3371 }
3372 ret = snprintf(path1, MAXPATHLEN, "%s/%s/lxc_rdepends", c->config_path,
3373 c->name);
3374 if (ret < 0 || ret >= MAXPATHLEN) {
3375 WARN("Error copying reverse dependencies");
3376 return;
3377 }
3378 if (copy_file(path0, path1) < 0) {
3379 INFO("Error copying reverse dependencies");
3380 return;
3381 }
3382 }
3383
3384 static bool add_rdepends(struct lxc_container *c, struct lxc_container *c0)
3385 {
3386 int ret;
3387 char path[MAXPATHLEN];
3388 FILE *f;
3389 bool bret;
3390
3391 ret = snprintf(path, MAXPATHLEN, "%s/%s/lxc_rdepends", c->config_path,
3392 c->name);
3393 if (ret < 0 || ret >= MAXPATHLEN)
3394 return false;
3395 f = fopen(path, "a");
3396 if (!f)
3397 return false;
3398 bret = true;
3399 /* If anything goes wrong, just return an error. */
3400 if (fprintf(f, "%s\n%s\n", c0->config_path, c0->name) < 0)
3401 bret = false;
3402 if (fclose(f) != 0)
3403 bret = false;
3404 return bret;
3405 }
3406
3407 /*
3408 * If the fs natively supports snapshot clones with no penalty,
3409 * then default to those even if not requested.
3410 * Currently we only do this for btrfs.
3411 */
3412 bool should_default_to_snapshot(struct lxc_container *c0,
3413 struct lxc_container *c1)
3414 {
3415 size_t l0 = strlen(c0->config_path) + strlen(c0->name) + 2;
3416 size_t l1 = strlen(c1->config_path) + strlen(c1->name) + 2;
3417 char *p0 = alloca(l0 + 1);
3418 char *p1 = alloca(l1 + 1);
3419 char *rootfs = c0->lxc_conf->rootfs.path;
3420
3421 snprintf(p0, l0, "%s/%s", c0->config_path, c0->name);
3422 snprintf(p1, l1, "%s/%s", c1->config_path, c1->name);
3423
3424 if (!is_btrfs_fs(p0) || !is_btrfs_fs(p1))
3425 return false;
3426
3427 if (is_btrfs_subvol(rootfs) <= 0)
3428 return false;
3429
3430 return btrfs_same_fs(p0, p1) == 0;
3431 }
3432
3433 static int copy_storage(struct lxc_container *c0, struct lxc_container *c,
3434 const char *newtype, int flags, const char *bdevdata,
3435 uint64_t newsize)
3436 {
3437 struct lxc_storage *bdev;
3438 bool need_rdep;
3439
3440 if (should_default_to_snapshot(c0, c))
3441 flags |= LXC_CLONE_SNAPSHOT;
3442
3443 bdev = storage_copy(c0, c->name, c->config_path, newtype, flags,
3444 bdevdata, newsize, &need_rdep);
3445 if (!bdev) {
3446 ERROR("Error copying storage.");
3447 return -1;
3448 }
3449
3450 /* Set new rootfs. */
3451 free(c->lxc_conf->rootfs.path);
3452 c->lxc_conf->rootfs.path = strdup(bdev->src);
3453 storage_put(bdev);
3454
3455 if (!c->lxc_conf->rootfs.path) {
3456 ERROR("Out of memory while setting storage path.");
3457 return -1;
3458 }
3459
3460 /* Append a new lxc.rootfs.path entry to the unexpanded config. */
3461 clear_unexp_config_line(c->lxc_conf, "lxc.rootfs.path", false);
3462 if (!do_append_unexp_config_line(c->lxc_conf, "lxc.rootfs.path",
3463 c->lxc_conf->rootfs.path)) {
3464 ERROR("Error saving new rootfs to cloned config.");
3465 return -1;
3466 }
3467
3468 if (flags & LXC_CLONE_SNAPSHOT)
3469 copy_rdepends(c, c0);
3470 if (need_rdep) {
3471 if (!add_rdepends(c, c0))
3472 WARN("Error adding reverse dependency from %s to %s",
3473 c->name, c0->name);
3474 }
3475
3476 mod_all_rdeps(c, true);
3477
3478 return 0;
3479 }
3480
3481 struct clone_update_data {
3482 struct lxc_container *c0;
3483 struct lxc_container *c1;
3484 int flags;
3485 char **hookargs;
3486 };
3487
3488 static int clone_update_rootfs(struct clone_update_data *data)
3489 {
3490 struct lxc_container *c0 = data->c0;
3491 struct lxc_container *c = data->c1;
3492 int flags = data->flags;
3493 char **hookargs = data->hookargs;
3494 int ret = -1;
3495 char path[MAXPATHLEN];
3496 struct lxc_storage *bdev;
3497 FILE *fout;
3498 struct lxc_conf *conf = c->lxc_conf;
3499
3500 /* update hostname in rootfs */
3501 /* we're going to mount, so run in a clean namespace to simplify cleanup */
3502
3503 if (setgid(0) < 0) {
3504 ERROR("Failed to setgid to 0");
3505 return -1;
3506 }
3507 if (setuid(0) < 0) {
3508 ERROR("Failed to setuid to 0");
3509 return -1;
3510 }
3511 if (setgroups(0, NULL) < 0)
3512 WARN("Failed to clear groups");
3513
3514 if (unshare(CLONE_NEWNS) < 0)
3515 return -1;
3516 bdev = storage_init(c->lxc_conf);
3517 if (!bdev)
3518 return -1;
3519 if (strcmp(bdev->type, "dir") != 0) {
3520 if (unshare(CLONE_NEWNS) < 0) {
3521 ERROR("error unsharing mounts");
3522 storage_put(bdev);
3523 return -1;
3524 }
3525 if (detect_shared_rootfs()) {
3526 if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL)) {
3527 SYSERROR("Failed to make / rslave");
3528 ERROR("Continuing...");
3529 }
3530 }
3531 if (bdev->ops->mount(bdev) < 0) {
3532 storage_put(bdev);
3533 return -1;
3534 }
3535 } else { /* TODO come up with a better way */
3536 free(bdev->dest);
3537 bdev->dest = strdup(bdev->src);
3538 }
3539
3540 if (!lxc_list_empty(&conf->hooks[LXCHOOK_CLONE])) {
3541 /* Start of environment variable setup for hooks */
3542 if (c0->name && setenv("LXC_SRC_NAME", c0->name, 1)) {
3543 SYSERROR("failed to set environment variable for source container name");
3544 }
3545 if (setenv("LXC_NAME", c->name, 1)) {
3546 SYSERROR("failed to set environment variable for container name");
3547 }
3548 if (conf->rcfile && setenv("LXC_CONFIG_FILE", conf->rcfile, 1)) {
3549 SYSERROR("failed to set environment variable for config path");
3550 }
3551 if (bdev->dest && setenv("LXC_ROOTFS_MOUNT", bdev->dest, 1)) {
3552 SYSERROR("failed to set environment variable for rootfs mount");
3553 }
3554 if (conf->rootfs.path && setenv("LXC_ROOTFS_PATH", conf->rootfs.path, 1)) {
3555 SYSERROR("failed to set environment variable for rootfs mount");
3556 }
3557
3558 if (run_lxc_hooks(c->name, "clone", conf, hookargs)) {
3559 ERROR("Error executing clone hook for %s", c->name);
3560 storage_put(bdev);
3561 return -1;
3562 }
3563 }
3564
3565 if (!(flags & LXC_CLONE_KEEPNAME)) {
3566 ret = snprintf(path, MAXPATHLEN, "%s/etc/hostname", bdev->dest);
3567 storage_put(bdev);
3568
3569 if (ret < 0 || ret >= MAXPATHLEN)
3570 return -1;
3571 if (!file_exists(path))
3572 return 0;
3573 if (!(fout = fopen(path, "w"))) {
3574 SYSERROR("unable to open %s: ignoring", path);
3575 return 0;
3576 }
3577 if (fprintf(fout, "%s", c->name) < 0) {
3578 fclose(fout);
3579 return -1;
3580 }
3581 if (fclose(fout) < 0)
3582 return -1;
3583 } else {
3584 storage_put(bdev);
3585 }
3586
3587 return 0;
3588 }
3589
3590 static int clone_update_rootfs_wrapper(void *data)
3591 {
3592 struct clone_update_data *arg = (struct clone_update_data *) data;
3593 return clone_update_rootfs(arg);
3594 }
3595
3596 /*
3597 * We want to support:
3598 sudo lxc-clone -o o1 -n n1 -s -L|-fssize fssize -v|--vgname vgname \
3599 -p|--lvprefix lvprefix -t|--fstype fstype -B backingstore
3600
3601 -s [ implies overlay]
3602 -s -B overlay
3603
3604 only rootfs gets converted (copied/snapshotted) on clone.
3605 */
3606
3607 static int create_file_dirname(char *path, struct lxc_conf *conf)
3608 {
3609 char *p = strrchr(path, '/');
3610 int ret = -1;
3611
3612 if (!p)
3613 return -1;
3614 *p = '\0';
3615 ret = do_create_container_dir(path, conf);
3616 *p = '/';
3617 return ret;
3618 }
3619
3620 static struct lxc_container *do_lxcapi_clone(struct lxc_container *c, const char *newname,
3621 const char *lxcpath, int flags,
3622 const char *bdevtype, const char *bdevdata, uint64_t newsize,
3623 char **hookargs)
3624 {
3625 char newpath[MAXPATHLEN];
3626 int fd, ret;
3627 struct clone_update_data data;
3628 size_t saved_unexp_len;
3629 pid_t pid;
3630 int storage_copied = 0;
3631 char *origroot = NULL, *saved_unexp_conf = NULL;
3632 struct lxc_container *c2 = NULL;
3633
3634 if (!c || !do_lxcapi_is_defined(c))
3635 return NULL;
3636
3637 if (container_mem_lock(c))
3638 return NULL;
3639
3640 if (!is_stopped(c)) {
3641 ERROR("error: Original container (%s) is running", c->name);
3642 goto out;
3643 }
3644
3645 /* Make sure the container doesn't yet exist. */
3646 if (!newname)
3647 newname = c->name;
3648 if (!lxcpath)
3649 lxcpath = do_lxcapi_get_config_path(c);
3650 ret = snprintf(newpath, MAXPATHLEN, "%s/%s/config", lxcpath, newname);
3651 if (ret < 0 || ret >= MAXPATHLEN) {
3652 SYSERROR("clone: failed making config pathname");
3653 goto out;
3654 }
3655
3656 if (file_exists(newpath)) {
3657 ERROR("error: clone: %s exists", newpath);
3658 goto out;
3659 }
3660
3661 ret = create_file_dirname(newpath, c->lxc_conf);
3662 if (ret < 0 && errno != EEXIST) {
3663 ERROR("Error creating container dir for %s", newpath);
3664 goto out;
3665 }
3666
3667 /* Copy the configuration. Tweak it as needed. */
3668 if (c->lxc_conf->rootfs.path) {
3669 origroot = c->lxc_conf->rootfs.path;
3670 c->lxc_conf->rootfs.path = NULL;
3671 }
3672
3673 fd = open(newpath, O_WRONLY | O_CREAT | O_CLOEXEC,
3674 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3675 if (fd < 0) {
3676 SYSERROR("Failed to open \"%s\"", newpath);
3677 goto out;
3678 }
3679
3680 saved_unexp_conf = c->lxc_conf->unexpanded_config;
3681 saved_unexp_len = c->lxc_conf->unexpanded_len;
3682 c->lxc_conf->unexpanded_config = strdup(saved_unexp_conf);
3683 if (!c->lxc_conf->unexpanded_config) {
3684 close(fd);
3685 goto out;
3686 }
3687
3688 clear_unexp_config_line(c->lxc_conf, "lxc.rootfs.path", false);
3689 write_config(fd, c->lxc_conf);
3690 close(fd);
3691 c->lxc_conf->rootfs.path = origroot;
3692 free(c->lxc_conf->unexpanded_config);
3693 c->lxc_conf->unexpanded_config = saved_unexp_conf;
3694 saved_unexp_conf = NULL;
3695 c->lxc_conf->unexpanded_len = saved_unexp_len;
3696
3697 ret = snprintf(newpath, MAXPATHLEN, "%s/%s/rootfs", lxcpath, newname);
3698 if (ret < 0 || ret >= MAXPATHLEN) {
3699 SYSERROR("clone: failed making rootfs pathname");
3700 goto out;
3701 }
3702
3703 ret = mkdir(newpath, 0755);
3704 if (ret < 0) {
3705 /* For an overlay container the rootfs is considered immutable
3706 * and will not have been removed when restoring from a
3707 * snapshot.
3708 */
3709 if (errno != ENOENT &&
3710 !(flags & LXC_STORAGE_INTERNAL_OVERLAY_RESTORE)) {
3711 SYSERROR("Failed to create directory \"%s\"", newpath);
3712 goto out;
3713 }
3714 }
3715
3716 if (am_guest_unpriv()) {
3717 if (chown_mapped_root(newpath, c->lxc_conf) < 0) {
3718 ERROR("Error chowning %s to container root", newpath);
3719 goto out;
3720 }
3721 }
3722
3723 c2 = lxc_container_new(newname, lxcpath);
3724 if (!c2) {
3725 ERROR("clone: failed to create new container (%s %s)", newname,
3726 lxcpath);
3727 goto out;
3728 }
3729
3730 /* copy/snapshot rootfs's */
3731 ret = copy_storage(c, c2, bdevtype, flags, bdevdata, newsize);
3732 if (ret < 0)
3733 goto out;
3734
3735
3736 /* update utsname */
3737 if (!(flags & LXC_CLONE_KEEPNAME)) {
3738 clear_unexp_config_line(c2->lxc_conf, "lxc.utsname", false);
3739 clear_unexp_config_line(c2->lxc_conf, "lxc.uts.name", false);
3740
3741 if (!do_set_config_item_locked(c2, "lxc.uts.name", newname)) {
3742 ERROR("Error setting new hostname");
3743 goto out;
3744 }
3745 }
3746
3747 /* copy hooks */
3748 ret = copyhooks(c, c2);
3749 if (ret < 0) {
3750 ERROR("error copying hooks");
3751 goto out;
3752 }
3753
3754 if (copy_fstab(c, c2) < 0) {
3755 ERROR("error copying fstab");
3756 goto out;
3757 }
3758
3759 /* update macaddrs */
3760 if (!(flags & LXC_CLONE_KEEPMACADDR)) {
3761 if (!network_new_hwaddrs(c2->lxc_conf)) {
3762 ERROR("Error updating mac addresses");
3763 goto out;
3764 }
3765 }
3766
3767 /* Update absolute paths for overlay mount directories. */
3768 if (ovl_update_abs_paths(c2->lxc_conf, c->config_path, c->name, lxcpath, newname) < 0)
3769 goto out;
3770
3771 /* We've now successfully created c2's storage, so clear it out if we
3772 * fail after this.
3773 */
3774 storage_copied = 1;
3775
3776 if (!c2->save_config(c2, NULL))
3777 goto out;
3778
3779 if ((pid = fork()) < 0) {
3780 SYSERROR("fork");
3781 goto out;
3782 }
3783 if (pid > 0) {
3784 ret = wait_for_pid(pid);
3785 if (ret)
3786 goto out;
3787 container_mem_unlock(c);
3788 return c2;
3789 }
3790 data.c0 = c;
3791 data.c1 = c2;
3792 data.flags = flags;
3793 data.hookargs = hookargs;
3794 if (am_guest_unpriv())
3795 ret = userns_exec_full(c->lxc_conf, clone_update_rootfs_wrapper,
3796 &data, "clone_update_rootfs_wrapper");
3797 else
3798 ret = clone_update_rootfs(&data);
3799 if (ret < 0)
3800 _exit(EXIT_FAILURE);
3801
3802 container_mem_unlock(c);
3803 _exit(EXIT_SUCCESS);
3804
3805 out:
3806 container_mem_unlock(c);
3807 if (c2) {
3808 if (!storage_copied)
3809 c2->lxc_conf->rootfs.path = NULL;
3810 c2->destroy(c2);
3811 lxc_container_put(c2);
3812 }
3813
3814 return NULL;
3815 }
3816
3817 static struct lxc_container *lxcapi_clone(struct lxc_container *c, const char *newname,
3818 const char *lxcpath, int flags,
3819 const char *bdevtype, const char *bdevdata, uint64_t newsize,
3820 char **hookargs)
3821 {
3822 struct lxc_container * ret;
3823 current_config = c ? c->lxc_conf : NULL;
3824 ret = do_lxcapi_clone(c, newname, lxcpath, flags, bdevtype, bdevdata, newsize, hookargs);
3825 current_config = NULL;
3826 return ret;
3827 }
3828
3829 static bool do_lxcapi_rename(struct lxc_container *c, const char *newname)
3830 {
3831 struct lxc_storage *bdev;
3832 struct lxc_container *newc;
3833
3834 if (!c || !c->name || !c->config_path || !c->lxc_conf)
3835 return false;
3836
3837 if (has_fs_snapshots(c) || has_snapshots(c)) {
3838 ERROR("Renaming a container with snapshots is not supported");
3839 return false;
3840 }
3841 bdev = storage_init(c->lxc_conf);
3842 if (!bdev) {
3843 ERROR("Failed to find original backing store type");
3844 return false;
3845 }
3846
3847 newc = lxcapi_clone(c, newname, c->config_path, LXC_CLONE_KEEPMACADDR, NULL, bdev->type, 0, NULL);
3848 storage_put(bdev);
3849 if (!newc) {
3850 lxc_container_put(newc);
3851 return false;
3852 }
3853
3854 if (newc && lxcapi_is_defined(newc))
3855 lxc_container_put(newc);
3856
3857 if (!container_destroy(c, NULL)) {
3858 ERROR("Could not destroy existing container %s", c->name);
3859 return false;
3860 }
3861 return true;
3862 }
3863
3864 WRAP_API_1(bool, lxcapi_rename, const char *)
3865
3866 static int lxcapi_attach(struct lxc_container *c, lxc_attach_exec_t exec_function, void *exec_payload, lxc_attach_options_t *options, pid_t *attached_process)
3867 {
3868 int ret;
3869
3870 if (!c)
3871 return -1;
3872
3873 current_config = c->lxc_conf;
3874
3875 ret = lxc_attach(c->name, c->config_path, exec_function, exec_payload, options, attached_process);
3876 current_config = NULL;
3877 return ret;
3878 }
3879
3880 static int do_lxcapi_attach_run_wait(struct lxc_container *c, lxc_attach_options_t *options, const char *program, const char * const argv[])
3881 {
3882 lxc_attach_command_t command;
3883 pid_t pid;
3884 int r;
3885
3886 if (!c)
3887 return -1;
3888
3889 command.program = (char*)program;
3890 command.argv = (char**)argv;
3891 r = lxc_attach(c->name, c->config_path, lxc_attach_run_command, &command, options, &pid);
3892 if (r < 0) {
3893 ERROR("ups");
3894 return r;
3895 }
3896 return lxc_wait_for_pid_status(pid);
3897 }
3898
3899 static int lxcapi_attach_run_wait(struct lxc_container *c, lxc_attach_options_t *options, const char *program, const char * const argv[])
3900 {
3901 int ret;
3902 current_config = c ? c->lxc_conf : NULL;
3903 ret = do_lxcapi_attach_run_wait(c, options, program, argv);
3904 current_config = NULL;
3905 return ret;
3906 }
3907
3908 static int get_next_index(const char *lxcpath, char *cname)
3909 {
3910 char *fname;
3911 struct stat sb;
3912 int i = 0, ret;
3913
3914 fname = alloca(strlen(lxcpath) + 20);
3915 while (1) {
3916 sprintf(fname, "%s/snap%d", lxcpath, i);
3917 ret = stat(fname, &sb);
3918 if (ret != 0)
3919 return i;
3920 i++;
3921 }
3922 }
3923
3924 static bool get_snappath_dir(struct lxc_container *c, char *snappath)
3925 {
3926 int ret;
3927 /*
3928 * If the old style snapshot path exists, use it
3929 * /var/lib/lxc -> /var/lib/lxcsnaps
3930 */
3931 ret = snprintf(snappath, MAXPATHLEN, "%ssnaps", c->config_path);
3932 if (ret < 0 || ret >= MAXPATHLEN)
3933 return false;
3934 if (dir_exists(snappath)) {
3935 ret = snprintf(snappath, MAXPATHLEN, "%ssnaps/%s", c->config_path, c->name);
3936 if (ret < 0 || ret >= MAXPATHLEN)
3937 return false;
3938 return true;
3939 }
3940
3941 /*
3942 * Use the new style path
3943 * /var/lib/lxc -> /var/lib/lxc + c->name + /snaps + \0
3944 */
3945 ret = snprintf(snappath, MAXPATHLEN, "%s/%s/snaps", c->config_path, c->name);
3946 if (ret < 0 || ret >= MAXPATHLEN)
3947 return false;
3948 return true;
3949 }
3950
3951 static int do_lxcapi_snapshot(struct lxc_container *c, const char *commentfile)
3952 {
3953 int i, flags, ret;
3954 struct lxc_container *c2;
3955 char snappath[MAXPATHLEN], newname[20];
3956
3957 if (!c || !lxcapi_is_defined(c))
3958 return -1;
3959
3960 if (!storage_can_backup(c->lxc_conf)) {
3961 ERROR("%s's backing store cannot be backed up.", c->name);
3962 ERROR("Your container must use another backing store type.");
3963 return -1;
3964 }
3965
3966 if (!get_snappath_dir(c, snappath))
3967 return -1;
3968
3969 i = get_next_index(snappath, c->name);
3970
3971 if (mkdir_p(snappath, 0755) < 0) {
3972 ERROR("Failed to create snapshot directory %s", snappath);
3973 return -1;
3974 }
3975
3976 ret = snprintf(newname, 20, "snap%d", i);
3977 if (ret < 0 || ret >= 20)
3978 return -1;
3979
3980 /*
3981 * We pass LXC_CLONE_SNAPSHOT to make sure that a rdepends file entry is
3982 * created in the original container
3983 */
3984 flags = LXC_CLONE_SNAPSHOT | LXC_CLONE_KEEPMACADDR | LXC_CLONE_KEEPNAME |
3985 LXC_CLONE_KEEPBDEVTYPE | LXC_CLONE_MAYBE_SNAPSHOT;
3986 if (storage_is_dir(c->lxc_conf)) {
3987 ERROR("Snapshot of directory-backed container requested.");
3988 ERROR("Making a copy-clone. If you do want snapshots, then");
3989 ERROR("please create overlay clone first, snapshot that");
3990 ERROR("and keep the original container pristine.");
3991 flags &= ~LXC_CLONE_SNAPSHOT | LXC_CLONE_MAYBE_SNAPSHOT;
3992 }
3993 c2 = do_lxcapi_clone(c, newname, snappath, flags, NULL, NULL, 0, NULL);
3994 if (!c2) {
3995 ERROR("clone of %s:%s failed", c->config_path, c->name);
3996 return -1;
3997 }
3998
3999 lxc_container_put(c2);
4000
4001 /* Now write down the creation time. */
4002 time_t timer;
4003 char buffer[25];
4004 struct tm* tm_info;
4005 FILE *f;
4006
4007 time(&timer);
4008 tm_info = localtime(&timer);
4009
4010 strftime(buffer, 25, "%Y:%m:%d %H:%M:%S", tm_info);
4011
4012 char *dfnam = alloca(strlen(snappath) + strlen(newname) + 5);
4013 sprintf(dfnam, "%s/%s/ts", snappath, newname);
4014 f = fopen(dfnam, "w");
4015 if (!f) {
4016 ERROR("Failed to open %s", dfnam);
4017 return -1;
4018 }
4019 if (fprintf(f, "%s", buffer) < 0) {
4020 SYSERROR("Writing timestamp");
4021 fclose(f);
4022 return -1;
4023 }
4024 ret = fclose(f);
4025 if (ret != 0) {
4026 SYSERROR("Writing timestamp");
4027 return -1;
4028 }
4029
4030 if (commentfile) {
4031 /* $p / $name / comment \0 */
4032 int len = strlen(snappath) + strlen(newname) + 10;
4033 char *path = alloca(len);
4034 sprintf(path, "%s/%s/comment", snappath, newname);
4035 return copy_file(commentfile, path) < 0 ? -1 : i;
4036 }
4037
4038 return i;
4039 }
4040
4041 WRAP_API_1(int, lxcapi_snapshot, const char *)
4042
4043 static void lxcsnap_free(struct lxc_snapshot *s)
4044 {
4045 free(s->name);
4046 free(s->comment_pathname);
4047 free(s->timestamp);
4048 free(s->lxcpath);
4049 }
4050
4051 static char *get_snapcomment_path(char* snappath, char *name)
4052 {
4053 /* $snappath/$name/comment */
4054 int ret, len = strlen(snappath) + strlen(name) + 10;
4055 char *s = malloc(len);
4056
4057 if (s) {
4058 ret = snprintf(s, len, "%s/%s/comment", snappath, name);
4059 if (ret < 0 || ret >= len) {
4060 free(s);
4061 s = NULL;
4062 }
4063 }
4064 return s;
4065 }
4066
4067 static char *get_timestamp(char* snappath, char *name)
4068 {
4069 char path[MAXPATHLEN], *s = NULL;
4070 int ret, len;
4071 FILE *fin;
4072
4073 ret = snprintf(path, MAXPATHLEN, "%s/%s/ts", snappath, name);
4074 if (ret < 0 || ret >= MAXPATHLEN)
4075 return NULL;
4076 fin = fopen(path, "r");
4077 if (!fin)
4078 return NULL;
4079 (void) fseek(fin, 0, SEEK_END);
4080 len = ftell(fin);
4081 (void) fseek(fin, 0, SEEK_SET);
4082 if (len > 0) {
4083 s = malloc(len+1);
4084 if (s) {
4085 s[len] = '\0';
4086 if (fread(s, 1, len, fin) != len) {
4087 SYSERROR("reading timestamp");
4088 free(s);
4089 s = NULL;
4090 }
4091 }
4092 }
4093 fclose(fin);
4094 return s;
4095 }
4096
4097 static int do_lxcapi_snapshot_list(struct lxc_container *c, struct lxc_snapshot **ret_snaps)
4098 {
4099 char snappath[MAXPATHLEN], path2[MAXPATHLEN];
4100 int count = 0, ret;
4101 struct dirent *direntp;
4102 struct lxc_snapshot *snaps =NULL, *nsnaps;
4103 DIR *dir;
4104
4105 if (!c || !lxcapi_is_defined(c))
4106 return -1;
4107
4108 if (!get_snappath_dir(c, snappath)) {
4109 ERROR("path name too long");
4110 return -1;
4111 }
4112 dir = opendir(snappath);
4113 if (!dir) {
4114 INFO("failed to open %s - assuming no snapshots", snappath);
4115 return 0;
4116 }
4117
4118 while ((direntp = readdir(dir))) {
4119 if (!strcmp(direntp->d_name, "."))
4120 continue;
4121
4122 if (!strcmp(direntp->d_name, ".."))
4123 continue;
4124
4125 ret = snprintf(path2, MAXPATHLEN, "%s/%s/config", snappath, direntp->d_name);
4126 if (ret < 0 || ret >= MAXPATHLEN) {
4127 ERROR("pathname too long");
4128 goto out_free;
4129 }
4130 if (!file_exists(path2))
4131 continue;
4132 nsnaps = realloc(snaps, (count + 1)*sizeof(*snaps));
4133 if (!nsnaps) {
4134 SYSERROR("Out of memory");
4135 goto out_free;
4136 }
4137 snaps = nsnaps;
4138 snaps[count].free = lxcsnap_free;
4139 snaps[count].name = strdup(direntp->d_name);
4140 if (!snaps[count].name)
4141 goto out_free;
4142 snaps[count].lxcpath = strdup(snappath);
4143 if (!snaps[count].lxcpath) {
4144 free(snaps[count].name);
4145 goto out_free;
4146 }
4147 snaps[count].comment_pathname = get_snapcomment_path(snappath, direntp->d_name);
4148 snaps[count].timestamp = get_timestamp(snappath, direntp->d_name);
4149 count++;
4150 }
4151
4152 if (closedir(dir))
4153 WARN("failed to close directory");
4154
4155 *ret_snaps = snaps;
4156 return count;
4157
4158 out_free:
4159 if (snaps) {
4160 int i;
4161 for (i=0; i<count; i++)
4162 lxcsnap_free(&snaps[i]);
4163 free(snaps);
4164 }
4165 if (closedir(dir))
4166 WARN("failed to close directory");
4167 return -1;
4168 }
4169
4170 WRAP_API_1(int, lxcapi_snapshot_list, struct lxc_snapshot **)
4171
4172 static bool do_lxcapi_snapshot_restore(struct lxc_container *c, const char *snapname, const char *newname)
4173 {
4174 char clonelxcpath[MAXPATHLEN];
4175 int flags = 0;
4176 struct lxc_container *snap, *rest;
4177 struct lxc_storage *bdev;
4178 bool b = false;
4179
4180 if (!c || !c->name || !c->config_path)
4181 return false;
4182
4183 if (has_fs_snapshots(c)) {
4184 ERROR("container rootfs has dependent snapshots");
4185 return false;
4186 }
4187
4188 bdev = storage_init(c->lxc_conf);
4189 if (!bdev) {
4190 ERROR("Failed to find original backing store type");
4191 return false;
4192 }
4193
4194 /* For an overlay container the rootfs is considered immutable
4195 * and cannot be removed when restoring from a snapshot. We pass this
4196 * internal flag along to communicate this to various parts of the
4197 * codebase.
4198 */
4199 if (!strcmp(bdev->type, "overlay") || !strcmp(bdev->type, "overlayfs"))
4200 bdev->flags |= LXC_STORAGE_INTERNAL_OVERLAY_RESTORE;
4201
4202 if (!newname)
4203 newname = c->name;
4204
4205 if (!get_snappath_dir(c, clonelxcpath)) {
4206 storage_put(bdev);
4207 return false;
4208 }
4209 /* how should we lock this? */
4210
4211 snap = lxc_container_new(snapname, clonelxcpath);
4212 if (!snap || !lxcapi_is_defined(snap)) {
4213 ERROR("Could not open snapshot %s", snapname);
4214 if (snap)
4215 lxc_container_put(snap);
4216 storage_put(bdev);
4217 return false;
4218 }
4219
4220 if (!strcmp(c->name, newname)) {
4221 if (!container_destroy(c, bdev)) {
4222 ERROR("Could not destroy existing container %s", newname);
4223 lxc_container_put(snap);
4224 storage_put(bdev);
4225 return false;
4226 }
4227 }
4228
4229 if (strcmp(bdev->type, "dir") != 0 && strcmp(bdev->type, "loop") != 0)
4230 flags = LXC_CLONE_SNAPSHOT | LXC_CLONE_MAYBE_SNAPSHOT;
4231
4232 if (!strcmp(bdev->type, "overlay") || !strcmp(bdev->type, "overlayfs"))
4233 flags |= LXC_STORAGE_INTERNAL_OVERLAY_RESTORE;
4234 rest = lxcapi_clone(snap, newname, c->config_path, flags, bdev->type,
4235 NULL, 0, NULL);
4236 storage_put(bdev);
4237 if (rest && lxcapi_is_defined(rest))
4238 b = true;
4239 if (rest)
4240 lxc_container_put(rest);
4241
4242 lxc_container_put(snap);
4243 return b;
4244 }
4245
4246 WRAP_API_2(bool, lxcapi_snapshot_restore, const char *, const char *)
4247
4248 static bool do_snapshot_destroy(const char *snapname, const char *clonelxcpath)
4249 {
4250 struct lxc_container *snap = NULL;
4251 bool bret = false;
4252
4253 snap = lxc_container_new(snapname, clonelxcpath);
4254 if (!snap) {
4255 ERROR("Could not find snapshot %s", snapname);
4256 goto err;
4257 }
4258
4259 if (!do_lxcapi_destroy(snap)) {
4260 ERROR("Could not destroy snapshot %s", snapname);
4261 goto err;
4262 }
4263 bret = true;
4264
4265 err:
4266 if (snap)
4267 lxc_container_put(snap);
4268 return bret;
4269 }
4270
4271 static bool remove_all_snapshots(const char *path)
4272 {
4273 DIR *dir;
4274 struct dirent *direntp;
4275 bool bret = true;
4276
4277 dir = opendir(path);
4278 if (!dir) {
4279 SYSERROR("opendir on snapshot path %s", path);
4280 return false;
4281 }
4282 while ((direntp = readdir(dir))) {
4283 if (!strcmp(direntp->d_name, "."))
4284 continue;
4285 if (!strcmp(direntp->d_name, ".."))
4286 continue;
4287 if (!do_snapshot_destroy(direntp->d_name, path)) {
4288 bret = false;
4289 continue;
4290 }
4291 }
4292
4293 closedir(dir);
4294
4295 if (rmdir(path))
4296 SYSERROR("Error removing directory %s", path);
4297
4298 return bret;
4299 }
4300
4301 static bool do_lxcapi_snapshot_destroy(struct lxc_container *c, const char *snapname)
4302 {
4303 char clonelxcpath[MAXPATHLEN];
4304
4305 if (!c || !c->name || !c->config_path || !snapname)
4306 return false;
4307
4308 if (!get_snappath_dir(c, clonelxcpath))
4309 return false;
4310
4311 return do_snapshot_destroy(snapname, clonelxcpath);
4312 }
4313
4314 WRAP_API_1(bool, lxcapi_snapshot_destroy, const char *)
4315
4316 static bool do_lxcapi_snapshot_destroy_all(struct lxc_container *c)
4317 {
4318 char clonelxcpath[MAXPATHLEN];
4319
4320 if (!c || !c->name || !c->config_path)
4321 return false;
4322
4323 if (!get_snappath_dir(c, clonelxcpath))
4324 return false;
4325
4326 return remove_all_snapshots(clonelxcpath);
4327 }
4328
4329 WRAP_API(bool, lxcapi_snapshot_destroy_all)
4330
4331 static bool do_lxcapi_may_control(struct lxc_container *c)
4332 {
4333 return lxc_try_cmd(c->name, c->config_path) == 0;
4334 }
4335
4336 WRAP_API(bool, lxcapi_may_control)
4337
4338 static bool do_add_remove_node(pid_t init_pid, const char *path, bool add,
4339 struct stat *st)
4340 {
4341 int ret;
4342 char *tmp;
4343 pid_t pid;
4344 char chrootpath[MAXPATHLEN];
4345 char *directory_path = NULL;
4346
4347 pid = fork();
4348 if (pid < 0) {
4349 SYSERROR("Failed to fork()");
4350 return false;
4351 }
4352
4353 if (pid) {
4354 ret = wait_for_pid(pid);
4355 if (ret != 0) {
4356 ERROR("Failed to create device node");
4357 return false;
4358 }
4359
4360 return true;
4361 }
4362
4363 /* prepare the path */
4364 ret = snprintf(chrootpath, MAXPATHLEN, "/proc/%d/root", init_pid);
4365 if (ret < 0 || ret >= MAXPATHLEN)
4366 return false;
4367
4368 ret = chroot(chrootpath);
4369 if (ret < 0)
4370 _exit(EXIT_FAILURE);
4371
4372 ret = chdir("/");
4373 if (ret < 0)
4374 _exit(EXIT_FAILURE);
4375
4376 /* remove path if it exists */
4377 ret = faccessat(AT_FDCWD, path, F_OK, AT_SYMLINK_NOFOLLOW);
4378 if(ret == 0) {
4379 ret = unlink(path);
4380 if (ret < 0) {
4381 ERROR("%s - Failed to remove \"%s\"", strerror(errno), path);
4382 _exit(EXIT_FAILURE);
4383 }
4384 }
4385
4386 if (!add)
4387 _exit(EXIT_SUCCESS);
4388
4389 /* create any missing directories */
4390 tmp = strdup(path);
4391 if (!tmp)
4392 _exit(EXIT_FAILURE);
4393
4394 directory_path = dirname(tmp);
4395 ret = mkdir_p(directory_path, 0755);
4396 if (ret < 0 && errno != EEXIST) {
4397 ERROR("%s - Failed to create path \"%s\"", strerror(errno), directory_path);
4398 free(tmp);
4399 _exit(EXIT_FAILURE);
4400 }
4401
4402 /* create the device node */
4403 ret = mknod(path, st->st_mode, st->st_rdev);
4404 free(tmp);
4405 if (ret < 0) {
4406 ERROR("%s - Failed to create device node at \"%s\"", strerror(errno), path);
4407 _exit(EXIT_FAILURE);
4408 }
4409
4410 _exit(EXIT_SUCCESS);
4411 }
4412
4413 static bool add_remove_device_node(struct lxc_container *c, const char *src_path, const char *dest_path, bool add)
4414 {
4415 int ret;
4416 struct stat st;
4417 char value[LXC_MAX_BUFFER];
4418 const char *p;
4419
4420 /* make sure container is running */
4421 if (!do_lxcapi_is_running(c)) {
4422 ERROR("container is not running");
4423 return false;
4424 }
4425
4426 /* use src_path if dest_path is NULL otherwise use dest_path */
4427 p = dest_path ? dest_path : src_path;
4428
4429 /* make sure we can access p */
4430 if(access(p, F_OK) < 0 || stat(p, &st) < 0)
4431 return false;
4432
4433 /* continue if path is character device or block device */
4434 if (S_ISCHR(st.st_mode))
4435 ret = snprintf(value, LXC_MAX_BUFFER, "c %d:%d rwm", major(st.st_rdev), minor(st.st_rdev));
4436 else if (S_ISBLK(st.st_mode))
4437 ret = snprintf(value, LXC_MAX_BUFFER, "b %d:%d rwm", major(st.st_rdev), minor(st.st_rdev));
4438 else
4439 return false;
4440
4441 /* check snprintf return code */
4442 if (ret < 0 || ret >= LXC_MAX_BUFFER)
4443 return false;
4444
4445 if (!do_add_remove_node(do_lxcapi_init_pid(c), p, add, &st))
4446 return false;
4447
4448 /* add or remove device to/from cgroup access list */
4449 if (add) {
4450 if (!do_lxcapi_set_cgroup_item(c, "devices.allow", value)) {
4451 ERROR("set_cgroup_item failed while adding the device node");
4452 return false;
4453 }
4454 } else {
4455 if (!do_lxcapi_set_cgroup_item(c, "devices.deny", value)) {
4456 ERROR("set_cgroup_item failed while removing the device node");
4457 return false;
4458 }
4459 }
4460
4461 return true;
4462 }
4463
4464 static bool do_lxcapi_add_device_node(struct lxc_container *c, const char *src_path, const char *dest_path)
4465 {
4466 // cannot mknod if we're not privileged wrt init_user_ns
4467 if (am_host_unpriv()) {
4468 ERROR(LXC_UNPRIV_EOPNOTSUPP, __FUNCTION__);
4469 return false;
4470 }
4471 return add_remove_device_node(c, src_path, dest_path, true);
4472 }
4473
4474 WRAP_API_2(bool, lxcapi_add_device_node, const char *, const char *)
4475
4476 static bool do_lxcapi_remove_device_node(struct lxc_container *c, const char *src_path, const char *dest_path)
4477 {
4478 if (am_guest_unpriv()) {
4479 ERROR(LXC_UNPRIV_EOPNOTSUPP, __FUNCTION__);
4480 return false;
4481 }
4482 return add_remove_device_node(c, src_path, dest_path, false);
4483 }
4484
4485 WRAP_API_2(bool, lxcapi_remove_device_node, const char *, const char *)
4486
4487 static bool do_lxcapi_attach_interface(struct lxc_container *c,
4488 const char *ifname,
4489 const char *dst_ifname)
4490 {
4491 pid_t init_pid;
4492 int ret = 0;
4493
4494 if (am_guest_unpriv()) {
4495 ERROR(LXC_UNPRIV_EOPNOTSUPP, __FUNCTION__);
4496 return false;
4497 }
4498
4499 if (!ifname) {
4500 ERROR("No source interface name given");
4501 return false;
4502 }
4503
4504 ret = lxc_netdev_isup(ifname);
4505 if (ret > 0) {
4506 /* netdev of ifname is up. */
4507 ret = lxc_netdev_down(ifname);
4508 if (ret)
4509 goto err;
4510 }
4511
4512 init_pid = do_lxcapi_init_pid(c);
4513 ret = lxc_netdev_move_by_name(ifname, init_pid, dst_ifname);
4514 if (ret)
4515 goto err;
4516
4517 INFO("Moved network device \"%s\" to network namespace of %d", ifname, init_pid);
4518 return true;
4519
4520 err:
4521 return false;
4522 }
4523
4524 WRAP_API_2(bool, lxcapi_attach_interface, const char *, const char *)
4525
4526 static bool do_lxcapi_detach_interface(struct lxc_container *c,
4527 const char *ifname,
4528 const char *dst_ifname)
4529 {
4530 int ret;
4531 pid_t pid, pid_outside;
4532
4533 /*
4534 * TODO - if this is a physical device, then we need am_host_unpriv.
4535 * But for other types guest privilege suffices.
4536 */
4537 if (am_guest_unpriv()) {
4538 ERROR(LXC_UNPRIV_EOPNOTSUPP, __FUNCTION__);
4539 return false;
4540 }
4541
4542 if (!ifname) {
4543 ERROR("No source interface name given");
4544 return false;
4545 }
4546
4547 pid_outside = lxc_raw_getpid();
4548 pid = fork();
4549 if (pid < 0) {
4550 ERROR("Failed to fork");
4551 return false;
4552 }
4553
4554 if (pid == 0) { /* child */
4555 pid_t init_pid;
4556
4557 init_pid = do_lxcapi_init_pid(c);
4558 if (!switch_to_ns(init_pid, "net")) {
4559 ERROR("Failed to enter network namespace");
4560 _exit(EXIT_FAILURE);
4561 }
4562
4563 ret = lxc_netdev_isup(ifname);
4564 if (ret < 0) {
4565 ERROR("Failed to determine whether network device \"%s\" is up", ifname);
4566 _exit(EXIT_FAILURE);
4567 }
4568
4569 /* netdev of ifname is up. */
4570 if (ret) {
4571 ret = lxc_netdev_down(ifname);
4572 if (ret) {
4573 ERROR("Failed to set network device \"%s\" down", ifname);
4574 _exit(EXIT_FAILURE);
4575 }
4576 }
4577
4578 ret = lxc_netdev_move_by_name(ifname, pid_outside, dst_ifname);
4579 /* -EINVAL means there is no netdev named as ifname. */
4580 if (ret < 0) {
4581 if (ret == -EINVAL)
4582 ERROR("Network device \"%s\" not found", ifname);
4583 else
4584 ERROR("Failed to remove network device \"%s\"", ifname);
4585 _exit(EXIT_FAILURE);
4586 }
4587
4588 _exit(EXIT_SUCCESS);
4589 }
4590
4591 ret = wait_for_pid(pid);
4592 if (ret != 0)
4593 return false;
4594
4595 INFO("Moved network device \"%s\" to network namespace of %d", ifname, pid_outside);
4596 return true;
4597 }
4598
4599 WRAP_API_2(bool, lxcapi_detach_interface, const char *, const char *)
4600
4601 static int do_lxcapi_migrate(struct lxc_container *c, unsigned int cmd,
4602 struct migrate_opts *opts, unsigned int size)
4603 {
4604 int ret = -1;
4605 struct migrate_opts *valid_opts = opts;
4606 uint64_t features_to_check = 0;
4607
4608 /* If the caller has a bigger (newer) struct migrate_opts, let's make
4609 * sure that the stuff on the end is zero, i.e. that they didn't ask us
4610 * to do anything special.
4611 */
4612 if (size > sizeof(*opts)) {
4613 unsigned char *addr;
4614 unsigned char *end;
4615
4616 addr = (void *)opts + sizeof(*opts);
4617 end = (void *)opts + size;
4618 for (; addr < end; addr++) {
4619 if (*addr) {
4620 return -E2BIG;
4621 }
4622 }
4623 }
4624
4625 /* If the caller has a smaller struct, let's zero out the end for them
4626 * so we don't accidentally use bits of it that they didn't know about
4627 * to initialize.
4628 */
4629 if (size < sizeof(*opts)) {
4630 valid_opts = malloc(sizeof(*opts));
4631 if (!valid_opts)
4632 return -ENOMEM;
4633
4634 memset(valid_opts, 0, sizeof(*opts));
4635 memcpy(valid_opts, opts, size);
4636 }
4637
4638 switch (cmd) {
4639 case MIGRATE_PRE_DUMP:
4640 if (!do_lxcapi_is_running(c)) {
4641 ERROR("container is not running");
4642 goto on_error;
4643 }
4644 ret = !__criu_pre_dump(c, valid_opts);
4645 break;
4646 case MIGRATE_DUMP:
4647 if (!do_lxcapi_is_running(c)) {
4648 ERROR("container is not running");
4649 goto on_error;
4650 }
4651 ret = !__criu_dump(c, valid_opts);
4652 break;
4653 case MIGRATE_RESTORE:
4654 if (do_lxcapi_is_running(c)) {
4655 ERROR("container is already running");
4656 goto on_error;
4657 }
4658 ret = !__criu_restore(c, valid_opts);
4659 break;
4660 case MIGRATE_FEATURE_CHECK:
4661 features_to_check = valid_opts->features_to_check;
4662 ret = !__criu_check_feature(&features_to_check);
4663 if (ret) {
4664 /* Something went wrong. Let's let the caller
4665 * know which feature checks failed. */
4666 valid_opts->features_to_check = features_to_check;
4667 }
4668 break;
4669 default:
4670 ERROR("invalid migrate command %u", cmd);
4671 ret = -EINVAL;
4672 }
4673
4674 on_error:
4675 if (size < sizeof(*opts))
4676 free(valid_opts);
4677
4678 return ret;
4679 }
4680
4681 WRAP_API_3(int, lxcapi_migrate, unsigned int, struct migrate_opts *, unsigned int)
4682
4683 static bool do_lxcapi_checkpoint(struct lxc_container *c, char *directory, bool stop, bool verbose)
4684 {
4685 struct migrate_opts opts;
4686
4687 memset(&opts, 0, sizeof(opts));
4688
4689 opts.directory = directory;
4690 opts.stop = stop;
4691 opts.verbose = verbose;
4692
4693 return !do_lxcapi_migrate(c, MIGRATE_DUMP, &opts, sizeof(opts));
4694 }
4695
4696 WRAP_API_3(bool, lxcapi_checkpoint, char *, bool, bool)
4697
4698 static bool do_lxcapi_restore(struct lxc_container *c, char *directory, bool verbose)
4699 {
4700 struct migrate_opts opts;
4701
4702 memset(&opts, 0, sizeof(opts));
4703
4704 opts.directory = directory;
4705 opts.verbose = verbose;
4706
4707 return !do_lxcapi_migrate(c, MIGRATE_RESTORE, &opts, sizeof(opts));
4708 }
4709
4710 WRAP_API_2(bool, lxcapi_restore, char *, bool)
4711
4712 static int lxcapi_attach_run_waitl(struct lxc_container *c, lxc_attach_options_t *options, const char *program, const char *arg, ...)
4713 {
4714 va_list ap;
4715 const char **argv;
4716 int ret;
4717
4718 if (!c)
4719 return -1;
4720
4721 current_config = c->lxc_conf;
4722
4723 va_start(ap, arg);
4724 argv = lxc_va_arg_list_to_argv_const(ap, 1);
4725 va_end(ap);
4726
4727 if (!argv) {
4728 ERROR("Memory allocation error.");
4729 ret = -1;
4730 goto out;
4731 }
4732 argv[0] = arg;
4733
4734 ret = do_lxcapi_attach_run_wait(c, options, program, (const char * const *)argv);
4735 free((void*)argv);
4736 out:
4737 current_config = NULL;
4738 return ret;
4739 }
4740
4741 struct lxc_container *lxc_container_new(const char *name, const char *configpath)
4742 {
4743 struct lxc_container *c;
4744
4745 if (!name)
4746 return NULL;
4747
4748 c = malloc(sizeof(*c));
4749 if (!c) {
4750 fprintf(stderr, "Failed to allocate memory for %s\n", name);
4751 return NULL;
4752 }
4753 memset(c, 0, sizeof(*c));
4754
4755 if (configpath)
4756 c->config_path = strdup(configpath);
4757 else
4758 c->config_path = strdup(lxc_global_config_value("lxc.lxcpath"));
4759
4760 if (!c->config_path) {
4761 fprintf(stderr, "Failed to allocate memory for %s\n", name);
4762 goto err;
4763 }
4764
4765 remove_trailing_slashes(c->config_path);
4766 c->name = malloc(strlen(name)+1);
4767 if (!c->name) {
4768 fprintf(stderr, "Failed to allocate memory for %s\n", name);
4769 goto err;
4770 }
4771 strcpy(c->name, name);
4772
4773 c->numthreads = 1;
4774 c->slock = lxc_newlock(c->config_path, name);
4775 if (!c->slock) {
4776 fprintf(stderr, "Failed to create lock for %s\n", name);
4777 goto err;
4778 }
4779
4780 c->privlock = lxc_newlock(NULL, NULL);
4781 if (!c->privlock) {
4782 fprintf(stderr, "Failed to create private lock for %s\n", name);
4783 goto err;
4784 }
4785
4786 if (!set_config_filename(c)) {
4787 fprintf(stderr, "Failed to create config file name for %s\n", name);
4788 goto err;
4789 }
4790
4791 if (file_exists(c->configfile) && !lxcapi_load_config(c, NULL)) {
4792 fprintf(stderr, "Failed to load config for %s\n", name);
4793 goto err;
4794 }
4795
4796 if (ongoing_create(c) == 2) {
4797 ERROR("Failed to complete container creation for %s", c->name);
4798 container_destroy(c, NULL);
4799 lxcapi_clear_config(c);
4800 }
4801 c->daemonize = true;
4802 c->pidfile = NULL;
4803
4804 /* Assign the member functions. */
4805 c->is_defined = lxcapi_is_defined;
4806 c->state = lxcapi_state;
4807 c->is_running = lxcapi_is_running;
4808 c->freeze = lxcapi_freeze;
4809 c->unfreeze = lxcapi_unfreeze;
4810 c->console = lxcapi_console;
4811 c->console_getfd = lxcapi_console_getfd;
4812 c->init_pid = lxcapi_init_pid;
4813 c->load_config = lxcapi_load_config;
4814 c->want_daemonize = lxcapi_want_daemonize;
4815 c->want_close_all_fds = lxcapi_want_close_all_fds;
4816 c->start = lxcapi_start;
4817 c->startl = lxcapi_startl;
4818 c->stop = lxcapi_stop;
4819 c->config_file_name = lxcapi_config_file_name;
4820 c->wait = lxcapi_wait;
4821 c->set_config_item = lxcapi_set_config_item;
4822 c->destroy = lxcapi_destroy;
4823 c->destroy_with_snapshots = lxcapi_destroy_with_snapshots;
4824 c->rename = lxcapi_rename;
4825 c->save_config = lxcapi_save_config;
4826 c->get_keys = lxcapi_get_keys;
4827 c->create = lxcapi_create;
4828 c->createl = lxcapi_createl;
4829 c->shutdown = lxcapi_shutdown;
4830 c->reboot = lxcapi_reboot;
4831 c->reboot2 = lxcapi_reboot2;
4832 c->clear_config = lxcapi_clear_config;
4833 c->clear_config_item = lxcapi_clear_config_item;
4834 c->get_config_item = lxcapi_get_config_item;
4835 c->get_running_config_item = lxcapi_get_running_config_item;
4836 c->get_cgroup_item = lxcapi_get_cgroup_item;
4837 c->set_cgroup_item = lxcapi_set_cgroup_item;
4838 c->get_config_path = lxcapi_get_config_path;
4839 c->set_config_path = lxcapi_set_config_path;
4840 c->clone = lxcapi_clone;
4841 c->get_interfaces = lxcapi_get_interfaces;
4842 c->get_ips = lxcapi_get_ips;
4843 c->attach = lxcapi_attach;
4844 c->attach_run_wait = lxcapi_attach_run_wait;
4845 c->attach_run_waitl = lxcapi_attach_run_waitl;
4846 c->snapshot = lxcapi_snapshot;
4847 c->snapshot_list = lxcapi_snapshot_list;
4848 c->snapshot_restore = lxcapi_snapshot_restore;
4849 c->snapshot_destroy = lxcapi_snapshot_destroy;
4850 c->snapshot_destroy_all = lxcapi_snapshot_destroy_all;
4851 c->may_control = lxcapi_may_control;
4852 c->add_device_node = lxcapi_add_device_node;
4853 c->remove_device_node = lxcapi_remove_device_node;
4854 c->attach_interface = lxcapi_attach_interface;
4855 c->detach_interface = lxcapi_detach_interface;
4856 c->checkpoint = lxcapi_checkpoint;
4857 c->restore = lxcapi_restore;
4858 c->migrate = lxcapi_migrate;
4859 c->console_log = lxcapi_console_log;
4860
4861 return c;
4862
4863 err:
4864 lxc_container_free(c);
4865 return NULL;
4866 }
4867
4868 int lxc_get_wait_states(const char **states)
4869 {
4870 int i;
4871
4872 if (states)
4873 for (i=0; i<MAX_STATE; i++)
4874 states[i] = lxc_state2str(i);
4875 return MAX_STATE;
4876 }
4877
4878 /*
4879 * These next two could probably be done smarter with reusing a common function
4880 * with different iterators and tests...
4881 */
4882 int list_defined_containers(const char *lxcpath, char ***names, struct lxc_container ***cret)
4883 {
4884 DIR *dir;
4885 int i, cfound = 0, nfound = 0;
4886 struct dirent *direntp;
4887 struct lxc_container *c;
4888
4889 if (!lxcpath)
4890 lxcpath = lxc_global_config_value("lxc.lxcpath");
4891
4892 dir = opendir(lxcpath);
4893 if (!dir) {
4894 SYSERROR("opendir on lxcpath");
4895 return -1;
4896 }
4897
4898 if (cret)
4899 *cret = NULL;
4900 if (names)
4901 *names = NULL;
4902
4903 while ((direntp = readdir(dir))) {
4904 /* Ignore '.', '..' and any hidden directory. */
4905 if (!strncmp(direntp->d_name, ".", 1))
4906 continue;
4907
4908 if (!config_file_exists(lxcpath, direntp->d_name))
4909 continue;
4910
4911 if (names) {
4912 if (!add_to_array(names, direntp->d_name, cfound))
4913 goto free_bad;
4914 }
4915 cfound++;
4916
4917 if (!cret) {
4918 nfound++;
4919 continue;
4920 }
4921
4922 c = lxc_container_new(direntp->d_name, lxcpath);
4923 if (!c) {
4924 INFO("Container %s:%s has a config but could not be loaded",
4925 lxcpath, direntp->d_name);
4926 if (names)
4927 if(!remove_from_array(names, direntp->d_name, cfound--))
4928 goto free_bad;
4929 continue;
4930 }
4931 if (!do_lxcapi_is_defined(c)) {
4932 INFO("Container %s:%s has a config but is not defined",
4933 lxcpath, direntp->d_name);
4934 if (names)
4935 if(!remove_from_array(names, direntp->d_name, cfound--))
4936 goto free_bad;
4937 lxc_container_put(c);
4938 continue;
4939 }
4940
4941 if (!add_to_clist(cret, c, nfound, true)) {
4942 lxc_container_put(c);
4943 goto free_bad;
4944 }
4945 nfound++;
4946 }
4947
4948 closedir(dir);
4949 return nfound;
4950
4951 free_bad:
4952 if (names && *names) {
4953 for (i=0; i<cfound; i++)
4954 free((*names)[i]);
4955 free(*names);
4956 }
4957 if (cret && *cret) {
4958 for (i=0; i<nfound; i++)
4959 lxc_container_put((*cret)[i]);
4960 free(*cret);
4961 }
4962 closedir(dir);
4963 return -1;
4964 }
4965
4966 int list_active_containers(const char *lxcpath, char ***nret,
4967 struct lxc_container ***cret)
4968 {
4969 int i, ret = -1, cret_cnt = 0, ct_name_cnt = 0;
4970 int lxcpath_len;
4971 char *line = NULL;
4972 char **ct_name = NULL;
4973 size_t len = 0;
4974 struct lxc_container *c = NULL;
4975 bool is_hashed;
4976
4977 if (!lxcpath)
4978 lxcpath = lxc_global_config_value("lxc.lxcpath");
4979 lxcpath_len = strlen(lxcpath);
4980
4981 if (cret)
4982 *cret = NULL;
4983 if (nret)
4984 *nret = NULL;
4985
4986 FILE *f = fopen("/proc/net/unix", "r");
4987 if (!f)
4988 return -1;
4989
4990 while (getline(&line, &len, f) != -1) {
4991
4992 char *p = strrchr(line, ' '), *p2;
4993 if (!p)
4994 continue;
4995 p++;
4996 if (*p != 0x40)
4997 continue;
4998 p++;
4999
5000 is_hashed = false;
5001 if (strncmp(p, lxcpath, lxcpath_len) == 0) {
5002 p += lxcpath_len;
5003 } else if (strncmp(p, "lxc/", 4) == 0) {
5004 p += 4;
5005 is_hashed = true;
5006 } else {
5007 continue;
5008 }
5009
5010 while (*p == '/')
5011 p++;
5012
5013 /* Now p is the start of lxc_name. */
5014 p2 = strchr(p, '/');
5015 if (!p2 || strncmp(p2, "/command", 8) != 0)
5016 continue;
5017 *p2 = '\0';
5018
5019 if (is_hashed) {
5020 char *recvpath = lxc_cmd_get_lxcpath(p);
5021 if (!recvpath)
5022 continue;
5023 if (strncmp(lxcpath, recvpath, lxcpath_len) != 0) {
5024 free(recvpath);
5025 continue;
5026 }
5027 free(recvpath);
5028 p = lxc_cmd_get_name(p);
5029 if (!p)
5030 continue;
5031 }
5032
5033 if (array_contains(&ct_name, p, ct_name_cnt)) {
5034 if (is_hashed)
5035 free(p);
5036 continue;
5037 }
5038
5039 if (!add_to_array(&ct_name, p, ct_name_cnt)) {
5040 if (is_hashed)
5041 free(p);
5042 goto free_cret_list;
5043 }
5044
5045 ct_name_cnt++;
5046
5047 if (!cret) {
5048 if (is_hashed)
5049 free(p);
5050 continue;
5051 }
5052
5053 c = lxc_container_new(p, lxcpath);
5054 if (!c) {
5055 INFO("Container %s:%s is running but could not be loaded",
5056 lxcpath, p);
5057 remove_from_array(&ct_name, p, ct_name_cnt--);
5058 if (is_hashed)
5059 free(p);
5060 continue;
5061 }
5062
5063 if (is_hashed)
5064 free(p);
5065
5066 /*
5067 * If this is an anonymous container, then is_defined *can*
5068 * return false. So we don't do that check. Count on the
5069 * fact that the command socket exists.
5070 */
5071
5072 if (!add_to_clist(cret, c, cret_cnt, true)) {
5073 lxc_container_put(c);
5074 goto free_cret_list;
5075 }
5076 cret_cnt++;
5077 }
5078
5079 if (nret && cret && cret_cnt != ct_name_cnt) {
5080 if (c)
5081 lxc_container_put(c);
5082 goto free_cret_list;
5083 }
5084
5085 ret = ct_name_cnt;
5086 if (nret)
5087 *nret = ct_name;
5088 else
5089 goto free_ct_name;
5090 goto out;
5091
5092 free_cret_list:
5093 if (cret && *cret) {
5094 for (i = 0; i < cret_cnt; i++)
5095 lxc_container_put((*cret)[i]);
5096 free(*cret);
5097 }
5098
5099 free_ct_name:
5100 if (ct_name) {
5101 for (i = 0; i < ct_name_cnt; i++)
5102 free(ct_name[i]);
5103 free(ct_name);
5104 }
5105
5106 out:
5107 free(line);
5108
5109 fclose(f);
5110 return ret;
5111 }
5112
5113 int list_all_containers(const char *lxcpath, char ***nret,
5114 struct lxc_container ***cret)
5115 {
5116 int i, ret, active_cnt, ct_cnt, ct_list_cnt;
5117 char **active_name;
5118 char **ct_name;
5119 struct lxc_container **ct_list = NULL;
5120
5121 ct_cnt = list_defined_containers(lxcpath, &ct_name, NULL);
5122 if (ct_cnt < 0)
5123 return ct_cnt;
5124
5125 active_cnt = list_active_containers(lxcpath, &active_name, NULL);
5126 if (active_cnt < 0) {
5127 ret = active_cnt;
5128 goto free_ct_name;
5129 }
5130
5131 for (i = 0; i < active_cnt; i++) {
5132 if (!array_contains(&ct_name, active_name[i], ct_cnt)) {
5133 if (!add_to_array(&ct_name, active_name[i], ct_cnt)) {
5134 ret = -1;
5135 goto free_active_name;
5136 }
5137 ct_cnt++;
5138 }
5139 free(active_name[i]);
5140 active_name[i] = NULL;
5141 }
5142 free(active_name);
5143 active_name = NULL;
5144 active_cnt = 0;
5145
5146 for (i = 0, ct_list_cnt = 0; i < ct_cnt && cret; i++) {
5147 struct lxc_container *c;
5148
5149 c = lxc_container_new(ct_name[i], lxcpath);
5150 if (!c) {
5151 WARN("Container %s:%s could not be loaded", lxcpath, ct_name[i]);
5152 remove_from_array(&ct_name, ct_name[i], ct_cnt--);
5153 continue;
5154 }
5155
5156 if (!add_to_clist(&ct_list, c, ct_list_cnt, false)) {
5157 lxc_container_put(c);
5158 ret = -1;
5159 goto free_ct_list;
5160 }
5161 ct_list_cnt++;
5162 }
5163
5164 if (cret)
5165 *cret = ct_list;
5166
5167 if (nret)
5168 *nret = ct_name;
5169 else {
5170 ret = ct_cnt;
5171 goto free_ct_name;
5172 }
5173 return ct_cnt;
5174
5175 free_ct_list:
5176 for (i = 0; i < ct_list_cnt; i++) {
5177 lxc_container_put(ct_list[i]);
5178 }
5179 free(ct_list);
5180
5181 free_active_name:
5182 for (i = 0; i < active_cnt; i++) {
5183 free(active_name[i]);
5184 }
5185 free(active_name);
5186
5187 free_ct_name:
5188 for (i = 0; i < ct_cnt; i++) {
5189 free(ct_name[i]);
5190 }
5191 free(ct_name);
5192 return ret;
5193 }
5194
5195 bool lxc_config_item_is_supported(const char *key)
5196 {
5197 return !!lxc_get_config(key);
5198 }
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