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btrfs-progs: docs: add note about mount option applicability
[btrfs-progs-unstable/devel.git] / cmds-receive.c
blobe584cef02ffe831f3b22f093535a6a5c48160656
1 /*
2 * Copyright (C) 2012 Alexander Block. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19 #include "kerncompat.h"
20 #include "androidcompat.h"
21
22 #include <unistd.h>
23 #include <stdint.h>
24 #include <dirent.h>
25 #include <fcntl.h>
26 #include <pthread.h>
27 #include <math.h>
28 #include <ftw.h>
29 #include <sys/wait.h>
30 #include <assert.h>
31 #include <getopt.h>
32 #include <limits.h>
33
34 #include <sys/stat.h>
35 #include <sys/types.h>
36 #include <sys/ioctl.h>
37 #include <sys/time.h>
38 #include <sys/types.h>
39 #include <sys/xattr.h>
40 #include <uuid/uuid.h>
41
42 #include "ctree.h"
43 #include "ioctl.h"
44 #include "commands.h"
45 #include "utils.h"
46 #include "list.h"
47 #include "btrfs-list.h"
48
49 #include "send.h"
50 #include "send-stream.h"
51 #include "send-utils.h"
52 #include "send-dump.h"
53 #include "help.h"
54
55 static int g_verbose = 0;
56
57 struct btrfs_receive
58 {
59 int mnt_fd;
60 int dest_dir_fd;
61
62 int write_fd;
63 char write_path[PATH_MAX];
64
65 char *root_path;
66 char *dest_dir_path; /* relative to root_path */
67 char full_subvol_path[PATH_MAX];
68 char *full_root_path;
69 int dest_dir_chroot;
70
71 struct subvol_info cur_subvol;
72 /*
73 * Substitute for cur_subvol::path which is a pointer and we cannot
74 * change it to an array as it's a public API.
75 */
76 char cur_subvol_path[PATH_MAX];
77
78 struct subvol_uuid_search sus;
79
80 int honor_end_cmd;
81
82 /*
83 * Buffer to store capabilities from security.capabilities xattr,
84 * usually 20 bytes, but make same room for potentially larger
85 * encodings. Must be set only once per file, denoted by length > 0.
86 */
87 char cached_capabilities[64];
88 int cached_capabilities_len;
89 };
90
91 static int finish_subvol(struct btrfs_receive *rctx)
92 {
93 int ret;
94 int subvol_fd = -1;
95 struct btrfs_ioctl_received_subvol_args rs_args;
96 char uuid_str[BTRFS_UUID_UNPARSED_SIZE];
97 u64 flags;
98
99 if (rctx->cur_subvol_path[0] == 0)
100 return 0;
101
102 subvol_fd = openat(rctx->mnt_fd, rctx->cur_subvol_path,
103 O_RDONLY | O_NOATIME);
104 if (subvol_fd < 0) {
105 ret = -errno;
106 error("cannot open %s: %s",
107 rctx->cur_subvol_path, strerror(-ret));
108 goto out;
109 }
110
111 memset(&rs_args, 0, sizeof(rs_args));
112 memcpy(rs_args.uuid, rctx->cur_subvol.received_uuid, BTRFS_UUID_SIZE);
113 rs_args.stransid = rctx->cur_subvol.stransid;
114
115 if (g_verbose >= 1) {
116 uuid_unparse((u8*)rs_args.uuid, uuid_str);
117 fprintf(stderr, "BTRFS_IOC_SET_RECEIVED_SUBVOL uuid=%s, "
118 "stransid=%llu\n", uuid_str, rs_args.stransid);
119 }
120
121 ret = ioctl(subvol_fd, BTRFS_IOC_SET_RECEIVED_SUBVOL, &rs_args);
122 if (ret < 0) {
123 ret = -errno;
124 error("ioctl BTRFS_IOC_SET_RECEIVED_SUBVOL failed: %s",
125 strerror(-ret));
126 goto out;
127 }
128 rctx->cur_subvol.rtransid = rs_args.rtransid;
129
130 ret = ioctl(subvol_fd, BTRFS_IOC_SUBVOL_GETFLAGS, &flags);
131 if (ret < 0) {
132 ret = -errno;
133 error("ioctl BTRFS_IOC_SUBVOL_GETFLAGS failed: %s",
134 strerror(-ret));
135 goto out;
136 }
137
138 flags |= BTRFS_SUBVOL_RDONLY;
139
140 ret = ioctl(subvol_fd, BTRFS_IOC_SUBVOL_SETFLAGS, &flags);
141 if (ret < 0) {
142 ret = -errno;
143 error("failed to make subvolume read only: %s",
144 strerror(-ret));
145 goto out;
146 }
147
148 ret = 0;
149
150 out:
151 if (rctx->cur_subvol_path[0]) {
152 rctx->cur_subvol_path[0] = 0;
153 }
154 if (subvol_fd != -1)
155 close(subvol_fd);
156 return ret;
157 }
158
159 static int process_subvol(const char *path, const u8 *uuid, u64 ctransid,
160 void *user)
161 {
162 int ret;
163 struct btrfs_receive *rctx = user;
164 struct btrfs_ioctl_vol_args args_v1;
165 char uuid_str[BTRFS_UUID_UNPARSED_SIZE];
166
167 ret = finish_subvol(rctx);
168 if (ret < 0)
169 goto out;
170
171 if (rctx->cur_subvol.path) {
172 error("subvol: another one already started, path ptr: %s",
173 rctx->cur_subvol.path);
174 ret = -EINVAL;
175 goto out;
176 }
177 if (rctx->cur_subvol_path[0]) {
178 error("subvol: another one already started, path buf: %s",
179 rctx->cur_subvol.path);
180 ret = -EINVAL;
181 goto out;
182 }
183
184 if (*rctx->dest_dir_path == 0) {
185 strncpy_null(rctx->cur_subvol_path, path);
186 } else {
187 ret = path_cat_out(rctx->cur_subvol_path, rctx->dest_dir_path,
188 path);
189 if (ret < 0) {
190 error("subvol: path invalid: %s", path);
191 goto out;
192 }
193 }
194 ret = path_cat3_out(rctx->full_subvol_path, rctx->root_path,
195 rctx->dest_dir_path, path);
196 if (ret < 0) {
197 error("subvol: path invalid: %s", path);
198 goto out;
199 }
200
201 fprintf(stderr, "At subvol %s\n", path);
202
203 memcpy(rctx->cur_subvol.received_uuid, uuid, BTRFS_UUID_SIZE);
204 rctx->cur_subvol.stransid = ctransid;
205
206 if (g_verbose) {
207 uuid_unparse((u8*)rctx->cur_subvol.received_uuid, uuid_str);
208 fprintf(stderr, "receiving subvol %s uuid=%s, stransid=%llu\n",
209 path, uuid_str,
210 rctx->cur_subvol.stransid);
211 }
212
213 memset(&args_v1, 0, sizeof(args_v1));
214 strncpy_null(args_v1.name, path);
215 ret = ioctl(rctx->dest_dir_fd, BTRFS_IOC_SUBVOL_CREATE, &args_v1);
216 if (ret < 0) {
217 ret = -errno;
218 error("creating subvolume %s failed: %s", path, strerror(-ret));
219 goto out;
220 }
221
222 out:
223 return ret;
224 }
225
226 static int process_snapshot(const char *path, const u8 *uuid, u64 ctransid,
227 const u8 *parent_uuid, u64 parent_ctransid,
228 void *user)
229 {
230 int ret;
231 struct btrfs_receive *rctx = user;
232 char uuid_str[BTRFS_UUID_UNPARSED_SIZE];
233 struct btrfs_ioctl_vol_args_v2 args_v2;
234 struct subvol_info *parent_subvol = NULL;
235
236 ret = finish_subvol(rctx);
237 if (ret < 0)
238 goto out;
239
240 if (rctx->cur_subvol.path) {
241 error("snapshot: another one already started, path ptr: %s",
242 rctx->cur_subvol.path);
243 ret = -EINVAL;
244 goto out;
245 }
246 if (rctx->cur_subvol_path[0]) {
247 error("snapshot: another one already started, path buf: %s",
248 rctx->cur_subvol.path);
249 ret = -EINVAL;
250 goto out;
251 }
252
253 if (*rctx->dest_dir_path == 0) {
254 strncpy_null(rctx->cur_subvol_path, path);
255 } else {
256 ret = path_cat_out(rctx->cur_subvol_path, rctx->dest_dir_path,
257 path);
258 if (ret < 0) {
259 error("snapshot: path invalid: %s", path);
260 goto out;
261 }
262 }
263 ret = path_cat3_out(rctx->full_subvol_path, rctx->root_path,
264 rctx->dest_dir_path, path);
265 if (ret < 0) {
266 error("snapshot: path invalid: %s", path);
267 goto out;
268 }
269
270 fprintf(stdout, "At snapshot %s\n", path);
271
272 memcpy(rctx->cur_subvol.received_uuid, uuid, BTRFS_UUID_SIZE);
273 rctx->cur_subvol.stransid = ctransid;
274
275 if (g_verbose) {
276 uuid_unparse((u8*)rctx->cur_subvol.received_uuid, uuid_str);
277 fprintf(stderr, "receiving snapshot %s uuid=%s, "
278 "ctransid=%llu ", path, uuid_str,
279 rctx->cur_subvol.stransid);
280 uuid_unparse(parent_uuid, uuid_str);
281 fprintf(stderr, "parent_uuid=%s, parent_ctransid=%llu\n",
282 uuid_str, parent_ctransid);
283 }
284
285 memset(&args_v2, 0, sizeof(args_v2));
286 strncpy_null(args_v2.name, path);
287
288 parent_subvol = subvol_uuid_search(&rctx->sus, 0, parent_uuid,
289 parent_ctransid, NULL,
290 subvol_search_by_received_uuid);
291 if (IS_ERR_OR_NULL(parent_subvol)) {
292 parent_subvol = subvol_uuid_search(&rctx->sus, 0, parent_uuid,
293 parent_ctransid, NULL,
294 subvol_search_by_uuid);
295 }
296 if (IS_ERR_OR_NULL(parent_subvol)) {
297 if (!parent_subvol)
298 ret = -ENOENT;
299 else
300 ret = PTR_ERR(parent_subvol);
301 error("cannot find parent subvolume");
302 goto out;
303 }
304
305 /*
306 * The path is resolved from the root subvol, but we could be in some
307 * subvolume under the root subvolume, so try and adjust the path to be
308 * relative to our root path.
309 */
310 if (rctx->full_root_path) {
311 size_t root_len;
312 size_t sub_len;
313
314 root_len = strlen(rctx->full_root_path);
315 sub_len = strlen(parent_subvol->path);
316
317 /* First make sure the parent subvol is actually in our path */
318 if (strstr(parent_subvol->path, rctx->full_root_path) != parent_subvol->path ||
319 (sub_len > root_len && parent_subvol->path[root_len] != '/')) {
320 error(
321 "parent subvol is not reachable from inside the root subvol");
322 ret = -ENOENT;
323 goto out;
324 }
325
326 if (sub_len == root_len) {
327 parent_subvol->path[0] = '.';
328 parent_subvol->path[1] = '\0';
329 } else {
330 /*
331 * root path is foo/bar
332 * subvol path is foo/bar/baz
333 *
334 * we need to have baz be the path, so we need to move
335 * the bit after foo/bar/, so path + root_len + 1, and
336 * move the part we care about, so sub_len - root_len -
337 * 1.
338 */
339 memmove(parent_subvol->path,
340 parent_subvol->path + root_len + 1,
341 sub_len - root_len - 1);
342 parent_subvol->path[sub_len - root_len - 1] = '\0';
343 }
344 }
345 /*if (rs_args.ctransid > rs_args.rtransid) {
346 if (!r->force) {
347 ret = -EINVAL;
348 fprintf(stderr, "ERROR: subvolume %s was modified after it was received.\n", r->subvol_parent_name);
349 goto out;
350 } else {
351 fprintf(stderr, "WARNING: subvolume %s was modified after it was received.\n", r->subvol_parent_name);
352 }
353 }*/
354
355 if (*parent_subvol->path == 0)
356 args_v2.fd = dup(rctx->mnt_fd);
357 else
358 args_v2.fd = openat(rctx->mnt_fd, parent_subvol->path,
359 O_RDONLY | O_NOATIME);
360 if (args_v2.fd < 0) {
361 ret = -errno;
362 if (errno != ENOENT)
363 error("cannot open %s: %s",
364 parent_subvol->path, strerror(-ret));
365 else
366 fprintf(stderr,
367 "It seems that you have changed your default "
368 "subvolume or you specify other subvolume to\n"
369 "mount btrfs, try to remount this btrfs filesystem "
370 "with fs tree, and run btrfs receive again!\n");
371 goto out;
372 }
373
374 ret = ioctl(rctx->dest_dir_fd, BTRFS_IOC_SNAP_CREATE_V2, &args_v2);
375 close(args_v2.fd);
376 if (ret < 0) {
377 ret = -errno;
378 error("creating snapshot %s -> %s failed: %s",
379 parent_subvol->path, path, strerror(-ret));
380 goto out;
381 }
382
383 out:
384 if (parent_subvol) {
385 free(parent_subvol->path);
386 free(parent_subvol);
387 }
388 return ret;
389 }
390
391 static int process_mkfile(const char *path, void *user)
392 {
393 int ret;
394 struct btrfs_receive *rctx = user;
395 char full_path[PATH_MAX];
396
397 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
398 if (ret < 0) {
399 error("mkfile: path invalid: %s", path);
400 goto out;
401 }
402
403 if (g_verbose >= 2)
404 fprintf(stderr, "mkfile %s\n", path);
405
406 ret = creat(full_path, 0600);
407 if (ret < 0) {
408 ret = -errno;
409 error("mkfile %s failed: %s", path, strerror(-ret));
410 goto out;
411 }
412 close(ret);
413 ret = 0;
414
415 out:
416 return ret;
417 }
418
419 static int process_mkdir(const char *path, void *user)
420 {
421 int ret;
422 struct btrfs_receive *rctx = user;
423 char full_path[PATH_MAX];
424
425 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
426 if (ret < 0) {
427 error("mkdir: path invalid: %s", path);
428 goto out;
429 }
430
431 if (g_verbose >= 2)
432 fprintf(stderr, "mkdir %s\n", path);
433
434 ret = mkdir(full_path, 0700);
435 if (ret < 0) {
436 ret = -errno;
437 error("mkdir %s failed: %s", path, strerror(-ret));
438 }
439
440 out:
441 return ret;
442 }
443
444 static int process_mknod(const char *path, u64 mode, u64 dev, void *user)
445 {
446 int ret;
447 struct btrfs_receive *rctx = user;
448 char full_path[PATH_MAX];
449
450 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
451 if (ret < 0) {
452 error("mknod: path invalid: %s", path);
453 goto out;
454 }
455
456 if (g_verbose >= 2)
457 fprintf(stderr, "mknod %s mode=%llu, dev=%llu\n",
458 path, mode, dev);
459
460 ret = mknod(full_path, mode & S_IFMT, dev);
461 if (ret < 0) {
462 ret = -errno;
463 error("mknod %s failed: %s", path, strerror(-ret));
464 }
465
466 out:
467 return ret;
468 }
469
470 static int process_mkfifo(const char *path, void *user)
471 {
472 int ret;
473 struct btrfs_receive *rctx = user;
474 char full_path[PATH_MAX];
475
476 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
477 if (ret < 0) {
478 error("mkfifo: path invalid: %s", path);
479 goto out;
480 }
481
482 if (g_verbose >= 2)
483 fprintf(stderr, "mkfifo %s\n", path);
484
485 ret = mkfifo(full_path, 0600);
486 if (ret < 0) {
487 ret = -errno;
488 error("mkfifo %s failed: %s", path, strerror(-ret));
489 }
490
491 out:
492 return ret;
493 }
494
495 static int process_mksock(const char *path, void *user)
496 {
497 int ret;
498 struct btrfs_receive *rctx = user;
499 char full_path[PATH_MAX];
500
501 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
502 if (ret < 0) {
503 error("mksock: path invalid: %s", path);
504 goto out;
505 }
506
507 if (g_verbose >= 2)
508 fprintf(stderr, "mksock %s\n", path);
509
510 ret = mknod(full_path, 0600 | S_IFSOCK, 0);
511 if (ret < 0) {
512 ret = -errno;
513 error("mknod %s failed: %s", path, strerror(-ret));
514 }
515
516 out:
517 return ret;
518 }
519
520 static int process_symlink(const char *path, const char *lnk, void *user)
521 {
522 int ret;
523 struct btrfs_receive *rctx = user;
524 char full_path[PATH_MAX];
525
526 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
527 if (ret < 0) {
528 error("symlink: path invalid: %s", path);
529 goto out;
530 }
531
532 if (g_verbose >= 2)
533 fprintf(stderr, "symlink %s -> %s\n", path, lnk);
534
535 ret = symlink(lnk, full_path);
536 if (ret < 0) {
537 ret = -errno;
538 error("symlink %s -> %s failed: %s", path,
539 lnk, strerror(-ret));
540 }
541
542 out:
543 return ret;
544 }
545
546 static int process_rename(const char *from, const char *to, void *user)
547 {
548 int ret;
549 struct btrfs_receive *rctx = user;
550 char full_from[PATH_MAX];
551 char full_to[PATH_MAX];
552
553 ret = path_cat_out(full_from, rctx->full_subvol_path, from);
554 if (ret < 0) {
555 error("rename: source path invalid: %s", from);
556 goto out;
557 }
558
559 ret = path_cat_out(full_to, rctx->full_subvol_path, to);
560 if (ret < 0) {
561 error("rename: target path invalid: %s", to);
562 goto out;
563 }
564
565 if (g_verbose >= 2)
566 fprintf(stderr, "rename %s -> %s\n", from, to);
567
568 ret = rename(full_from, full_to);
569 if (ret < 0) {
570 ret = -errno;
571 error("rename %s -> %s failed: %s", from,
572 to, strerror(-ret));
573 }
574
575 out:
576 return ret;
577 }
578
579 static int process_link(const char *path, const char *lnk, void *user)
580 {
581 int ret;
582 struct btrfs_receive *rctx = user;
583 char full_path[PATH_MAX];
584 char full_link_path[PATH_MAX];
585
586 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
587 if (ret < 0) {
588 error("link: source path invalid: %s", full_path);
589 goto out;
590 }
591
592 ret = path_cat_out(full_link_path, rctx->full_subvol_path, lnk);
593 if (ret < 0) {
594 error("link: target path invalid: %s", full_link_path);
595 goto out;
596 }
597
598 if (g_verbose >= 2)
599 fprintf(stderr, "link %s -> %s\n", path, lnk);
600
601 ret = link(full_link_path, full_path);
602 if (ret < 0) {
603 ret = -errno;
604 error("link %s -> %s failed: %s", path, lnk, strerror(-ret));
605 }
606
607 out:
608 return ret;
609 }
610
611
612 static int process_unlink(const char *path, void *user)
613 {
614 int ret;
615 struct btrfs_receive *rctx = user;
616 char full_path[PATH_MAX];
617
618 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
619 if (ret < 0) {
620 error("unlink: path invalid: %s", path);
621 goto out;
622 }
623
624 if (g_verbose >= 2)
625 fprintf(stderr, "unlink %s\n", path);
626
627 ret = unlink(full_path);
628 if (ret < 0) {
629 ret = -errno;
630 error("unlink %s failed. %s", path, strerror(-ret));
631 }
632
633 out:
634 return ret;
635 }
636
637 static int process_rmdir(const char *path, void *user)
638 {
639 int ret;
640 struct btrfs_receive *rctx = user;
641 char full_path[PATH_MAX];
642
643 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
644 if (ret < 0) {
645 error("rmdir: path invalid: %s", path);
646 goto out;
647 }
648
649 if (g_verbose >= 2)
650 fprintf(stderr, "rmdir %s\n", path);
651
652 ret = rmdir(full_path);
653 if (ret < 0) {
654 ret = -errno;
655 error("rmdir %s failed: %s", path, strerror(-ret));
656 }
657
658 out:
659 return ret;
660 }
661
662 static int open_inode_for_write(struct btrfs_receive *rctx, const char *path)
663 {
664 int ret = 0;
665
666 if (rctx->write_fd != -1) {
667 if (strcmp(rctx->write_path, path) == 0)
668 goto out;
669 close(rctx->write_fd);
670 rctx->write_fd = -1;
671 }
672
673 rctx->write_fd = open(path, O_RDWR);
674 if (rctx->write_fd < 0) {
675 ret = -errno;
676 error("cannot open %s: %s", path, strerror(-ret));
677 goto out;
678 }
679 strncpy_null(rctx->write_path, path);
680
681 out:
682 return ret;
683 }
684
685 static void close_inode_for_write(struct btrfs_receive *rctx)
686 {
687 if(rctx->write_fd == -1)
688 return;
689
690 close(rctx->write_fd);
691 rctx->write_fd = -1;
692 rctx->write_path[0] = 0;
693 }
694
695 static int process_write(const char *path, const void *data, u64 offset,
696 u64 len, void *user)
697 {
698 int ret = 0;
699 struct btrfs_receive *rctx = user;
700 char full_path[PATH_MAX];
701 u64 pos = 0;
702 int w;
703
704 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
705 if (ret < 0) {
706 error("write: path invalid: %s", path);
707 goto out;
708 }
709
710 ret = open_inode_for_write(rctx, full_path);
711 if (ret < 0)
712 goto out;
713
714 while (pos < len) {
715 w = pwrite(rctx->write_fd, (char*)data + pos, len - pos,
716 offset + pos);
717 if (w < 0) {
718 ret = -errno;
719 error("writing to %s failed: %s",
720 path, strerror(-ret));
721 goto out;
722 }
723 pos += w;
724 }
725
726 out:
727 return ret;
728 }
729
730 static int process_clone(const char *path, u64 offset, u64 len,
731 const u8 *clone_uuid, u64 clone_ctransid,
732 const char *clone_path, u64 clone_offset,
733 void *user)
734 {
735 int ret;
736 struct btrfs_receive *rctx = user;
737 struct btrfs_ioctl_clone_range_args clone_args;
738 struct subvol_info *si = NULL;
739 char full_path[PATH_MAX];
740 char *subvol_path = NULL;
741 char full_clone_path[PATH_MAX];
742 int clone_fd = -1;
743
744 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
745 if (ret < 0) {
746 error("clone: source path invalid: %s", path);
747 goto out;
748 }
749
750 ret = open_inode_for_write(rctx, full_path);
751 if (ret < 0)
752 goto out;
753
754 si = subvol_uuid_search(&rctx->sus, 0, clone_uuid, clone_ctransid,
755 NULL,
756 subvol_search_by_received_uuid);
757 if (IS_ERR_OR_NULL(si)) {
758 if (memcmp(clone_uuid, rctx->cur_subvol.received_uuid,
759 BTRFS_UUID_SIZE) == 0) {
760 /* TODO check generation of extent */
761 subvol_path = strdup(rctx->cur_subvol_path);
762 } else {
763 if (!si)
764 ret = -ENOENT;
765 else
766 ret = PTR_ERR(si);
767 error("clone: did not find source subvol");
768 goto out;
769 }
770 } else {
771 /*if (rs_args.ctransid > rs_args.rtransid) {
772 if (!r->force) {
773 ret = -EINVAL;
774 fprintf(stderr, "ERROR: subvolume %s was "
775 "modified after it was "
776 "received.\n",
777 r->subvol_parent_name);
778 goto out;
779 } else {
780 fprintf(stderr, "WARNING: subvolume %s was "
781 "modified after it was "
782 "received.\n",
783 r->subvol_parent_name);
784 }
785 }*/
786
787 /* strip the subvolume that we are receiving to from the start of subvol_path */
788 if (rctx->full_root_path) {
789 size_t root_len = strlen(rctx->full_root_path);
790 size_t sub_len = strlen(si->path);
791
792 if (sub_len > root_len &&
793 strstr(si->path, rctx->full_root_path) == si->path &&
794 si->path[root_len] == '/') {
795 subvol_path = strdup(si->path + root_len + 1);
796 } else {
797 error("clone: source subvol path %s unreachable from %s",
798 si->path, rctx->full_root_path);
799 goto out;
800 }
801 } else {
802 subvol_path = strdup(si->path);
803 }
804 }
805
806 ret = path_cat_out(full_clone_path, subvol_path, clone_path);
807 if (ret < 0) {
808 error("clone: target path invalid: %s", clone_path);
809 goto out;
810 }
811
812 clone_fd = openat(rctx->mnt_fd, full_clone_path, O_RDONLY | O_NOATIME);
813 if (clone_fd < 0) {
814 ret = -errno;
815 error("cannot open %s: %s", full_clone_path, strerror(-ret));
816 goto out;
817 }
818
819 clone_args.src_fd = clone_fd;
820 clone_args.src_offset = clone_offset;
821 clone_args.src_length = len;
822 clone_args.dest_offset = offset;
823 ret = ioctl(rctx->write_fd, BTRFS_IOC_CLONE_RANGE, &clone_args);
824 if (ret < 0) {
825 ret = -errno;
826 error("failed to clone extents to %s\n%s",
827 path, strerror(-ret));
828 goto out;
829 }
830
831 out:
832 if (si) {
833 free(si->path);
834 free(si);
835 }
836 free(subvol_path);
837 if (clone_fd != -1)
838 close(clone_fd);
839 return ret;
840 }
841
842
843 static int process_set_xattr(const char *path, const char *name,
844 const void *data, int len, void *user)
845 {
846 int ret = 0;
847 struct btrfs_receive *rctx = user;
848 char full_path[PATH_MAX];
849
850 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
851 if (ret < 0) {
852 error("set_xattr: path invalid: %s", path);
853 goto out;
854 }
855
856 if (strcmp("security.capability", name) == 0) {
857 if (g_verbose >= 3)
858 fprintf(stderr, "set_xattr: cache capabilities\n");
859 if (rctx->cached_capabilities_len)
860 warning("capabilities set multiple times per file: %s",
861 full_path);
862 if (len > sizeof(rctx->cached_capabilities)) {
863 error("capabilities encoded to %d bytes, buffer too small",
864 len);
865 ret = -E2BIG;
866 goto out;
867 }
868 rctx->cached_capabilities_len = len;
869 memcpy(rctx->cached_capabilities, data, len);
870 }
871
872 if (g_verbose >= 2) {
873 fprintf(stderr, "set_xattr %s - name=%s data_len=%d "
874 "data=%.*s\n", path, name, len,
875 len, (char*)data);
876 }
877
878 ret = lsetxattr(full_path, name, data, len, 0);
879 if (ret < 0) {
880 ret = -errno;
881 error("lsetxattr %s %s=%.*s failed: %s",
882 path, name, len, (char*)data, strerror(-ret));
883 goto out;
884 }
885
886 out:
887 return ret;
888 }
889
890 static int process_remove_xattr(const char *path, const char *name, void *user)
891 {
892 int ret = 0;
893 struct btrfs_receive *rctx = user;
894 char full_path[PATH_MAX];
895
896 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
897 if (ret < 0) {
898 error("remove_xattr: path invalid: %s", path);
899 goto out;
900 }
901
902 if (g_verbose >= 2) {
903 fprintf(stderr, "remove_xattr %s - name=%s\n",
904 path, name);
905 }
906
907 ret = lremovexattr(full_path, name);
908 if (ret < 0) {
909 ret = -errno;
910 error("lremovexattr %s %s failed: %s",
911 path, name, strerror(-ret));
912 goto out;
913 }
914
915 out:
916 return ret;
917 }
918
919 static int process_truncate(const char *path, u64 size, void *user)
920 {
921 int ret = 0;
922 struct btrfs_receive *rctx = user;
923 char full_path[PATH_MAX];
924
925 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
926 if (ret < 0) {
927 error("truncate: path invalid: %s", path);
928 goto out;
929 }
930
931 if (g_verbose >= 2)
932 fprintf(stderr, "truncate %s size=%llu\n", path, size);
933
934 ret = truncate(full_path, size);
935 if (ret < 0) {
936 ret = -errno;
937 error("truncate %s failed: %s", path, strerror(-ret));
938 goto out;
939 }
940
941 out:
942 return ret;
943 }
944
945 static int process_chmod(const char *path, u64 mode, void *user)
946 {
947 int ret = 0;
948 struct btrfs_receive *rctx = user;
949 char full_path[PATH_MAX];
950
951 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
952 if (ret < 0) {
953 error("chmod: path invalid: %s", path);
954 goto out;
955 }
956
957 if (g_verbose >= 2)
958 fprintf(stderr, "chmod %s - mode=0%o\n", path, (int)mode);
959
960 ret = chmod(full_path, mode);
961 if (ret < 0) {
962 ret = -errno;
963 error("chmod %s failed: %s", path, strerror(-ret));
964 goto out;
965 }
966
967 out:
968 return ret;
969 }
970
971 static int process_chown(const char *path, u64 uid, u64 gid, void *user)
972 {
973 int ret = 0;
974 struct btrfs_receive *rctx = user;
975 char full_path[PATH_MAX];
976
977 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
978 if (ret < 0) {
979 error("chown: path invalid: %s", path);
980 goto out;
981 }
982
983 if (g_verbose >= 2)
984 fprintf(stderr, "chown %s - uid=%llu, gid=%llu\n", path,
985 uid, gid);
986
987 ret = lchown(full_path, uid, gid);
988 if (ret < 0) {
989 ret = -errno;
990 error("chown %s failed: %s", path, strerror(-ret));
991 goto out;
992 }
993
994 if (rctx->cached_capabilities_len) {
995 if (g_verbose >= 2)
996 fprintf(stderr, "chown: restore capabilities\n");
997 ret = lsetxattr(full_path, "security.capability",
998 rctx->cached_capabilities,
999 rctx->cached_capabilities_len, 0);
1000 memset(rctx->cached_capabilities, 0,
1001 sizeof(rctx->cached_capabilities));
1002 rctx->cached_capabilities_len = 0;
1003 if (ret < 0) {
1004 ret = -errno;
1005 error("restoring capabilities %s: %s",
1006 path, strerror(-ret));
1007 goto out;
1008 }
1009 }
1010
1011 out:
1012 return ret;
1013 }
1014
1015 static int process_utimes(const char *path, struct timespec *at,
1016 struct timespec *mt, struct timespec *ct,
1017 void *user)
1018 {
1019 int ret = 0;
1020 struct btrfs_receive *rctx = user;
1021 char full_path[PATH_MAX];
1022 struct timespec tv[2];
1023
1024 ret = path_cat_out(full_path, rctx->full_subvol_path, path);
1025 if (ret < 0) {
1026 error("utimes: path invalid: %s", path);
1027 goto out;
1028 }
1029
1030 if (g_verbose >= 2)
1031 fprintf(stderr, "utimes %s\n", path);
1032
1033 tv[0] = *at;
1034 tv[1] = *mt;
1035 ret = utimensat(AT_FDCWD, full_path, tv, AT_SYMLINK_NOFOLLOW);
1036 if (ret < 0) {
1037 ret = -errno;
1038 error("utimes %s failed: %s",
1039 path, strerror(-ret));
1040 goto out;
1041 }
1042
1043 out:
1044 return ret;
1045 }
1046
1047 static int process_update_extent(const char *path, u64 offset, u64 len,
1048 void *user)
1049 {
1050 if (g_verbose >= 2)
1051 fprintf(stderr, "update_extent %s: offset=%llu, len=%llu\n",
1052 path, (unsigned long long)offset,
1053 (unsigned long long)len);
1054
1055 /*
1056 * Sent with BTRFS_SEND_FLAG_NO_FILE_DATA, nothing to do.
1057 */
1058
1059 return 0;
1060 }
1061
1062 static struct btrfs_send_ops send_ops = {
1063 .subvol = process_subvol,
1064 .snapshot = process_snapshot,
1065 .mkfile = process_mkfile,
1066 .mkdir = process_mkdir,
1067 .mknod = process_mknod,
1068 .mkfifo = process_mkfifo,
1069 .mksock = process_mksock,
1070 .symlink = process_symlink,
1071 .rename = process_rename,
1072 .link = process_link,
1073 .unlink = process_unlink,
1074 .rmdir = process_rmdir,
1075 .write = process_write,
1076 .clone = process_clone,
1077 .set_xattr = process_set_xattr,
1078 .remove_xattr = process_remove_xattr,
1079 .truncate = process_truncate,
1080 .chmod = process_chmod,
1081 .chown = process_chown,
1082 .utimes = process_utimes,
1083 .update_extent = process_update_extent,
1084 };
1085
1086 static int do_receive(struct btrfs_receive *rctx, const char *tomnt,
1087 char *realmnt, int r_fd, u64 max_errors)
1088 {
1089 u64 subvol_id;
1090 int ret;
1091 char *dest_dir_full_path;
1092 char root_subvol_path[PATH_MAX];
1093 int end = 0;
1094 int iterations = 0;
1095
1096 dest_dir_full_path = realpath(tomnt, NULL);
1097 if (!dest_dir_full_path) {
1098 ret = -errno;
1099 error("realpath(%s) failed: %s", tomnt, strerror(-ret));
1100 goto out;
1101 }
1102 rctx->dest_dir_fd = open(dest_dir_full_path, O_RDONLY | O_NOATIME);
1103 if (rctx->dest_dir_fd < 0) {
1104 ret = -errno;
1105 error("cannot open destination directory %s: %s",
1106 dest_dir_full_path, strerror(-ret));
1107 goto out;
1108 }
1109
1110 if (realmnt[0]) {
1111 rctx->root_path = realmnt;
1112 } else {
1113 ret = find_mount_root(dest_dir_full_path, &rctx->root_path);
1114 if (ret < 0) {
1115 error("failed to determine mount point for %s: %s",
1116 dest_dir_full_path, strerror(-ret));
1117 ret = -EINVAL;
1118 goto out;
1119 }
1120 if (ret > 0) {
1121 error("%s doesn't belong to btrfs mount point",
1122 dest_dir_full_path);
1123 ret = -EINVAL;
1124 goto out;
1125 }
1126 }
1127 rctx->mnt_fd = open(rctx->root_path, O_RDONLY | O_NOATIME);
1128 if (rctx->mnt_fd < 0) {
1129 ret = -errno;
1130 error("cannot open %s: %s", rctx->root_path, strerror(-ret));
1131 goto out;
1132 }
1133
1134 /*
1135 * If we use -m or a default subvol we want to resolve the path to the
1136 * subvolume we're sitting in so that we can adjust the paths of any
1137 * subvols we want to receive in.
1138 */
1139 ret = btrfs_list_get_path_rootid(rctx->mnt_fd, &subvol_id);
1140 if (ret)
1141 goto out;
1142
1143 root_subvol_path[0] = 0;
1144 ret = btrfs_subvolid_resolve(rctx->mnt_fd, root_subvol_path,
1145 PATH_MAX, subvol_id);
1146 if (ret) {
1147 error("cannot resolve our subvol path");
1148 goto out;
1149 }
1150
1151 /*
1152 * Ok we're inside of a subvol off of the root subvol, we need to
1153 * actually set full_root_path.
1154 */
1155 if (*root_subvol_path)
1156 rctx->full_root_path = root_subvol_path;
1157
1158 if (rctx->dest_dir_chroot) {
1159 if (chroot(dest_dir_full_path)) {
1160 ret = -errno;
1161 error("failed to chroot to %s: %s",
1162 dest_dir_full_path, strerror(-ret));
1163 goto out;
1164 }
1165 if (chdir("/")) {
1166 ret = -errno;
1167 error("failed to chdir to / after chroot: %s",
1168 strerror(-ret));
1169 goto out;
1170 }
1171 fprintf(stderr, "Chroot to %s\n", dest_dir_full_path);
1172 rctx->root_path = strdup("/");
1173 rctx->dest_dir_path = rctx->root_path;
1174 } else {
1175 /*
1176 * find_mount_root returns a root_path that is a subpath of
1177 * dest_dir_full_path. Now get the other part of root_path,
1178 * which is the destination dir relative to root_path.
1179 */
1180 rctx->dest_dir_path = dest_dir_full_path + strlen(rctx->root_path);
1181 while (rctx->dest_dir_path[0] == '/')
1182 rctx->dest_dir_path++;
1183 }
1184
1185 ret = subvol_uuid_search_init(rctx->mnt_fd, &rctx->sus);
1186 if (ret < 0)
1187 goto out;
1188
1189 while (!end) {
1190 if (rctx->cached_capabilities_len) {
1191 if (g_verbose >= 3)
1192 fprintf(stderr, "clear cached capabilities\n");
1193 memset(rctx->cached_capabilities, 0,
1194 sizeof(rctx->cached_capabilities));
1195 rctx->cached_capabilities_len = 0;
1196 }
1197
1198 ret = btrfs_read_and_process_send_stream(r_fd, &send_ops,
1199 rctx,
1200 rctx->honor_end_cmd,
1201 max_errors);
1202 if (ret < 0) {
1203 if (ret != -ENODATA)
1204 goto out;
1205
1206 /* Empty stream is invalid */
1207 if (iterations == 0) {
1208 error("empty stream is not considered valid");
1209 ret = -EINVAL;
1210 goto out;
1211 }
1212
1213 ret = 1;
1214 }
1215 if (ret > 0)
1216 end = 1;
1217
1218 close_inode_for_write(rctx);
1219 ret = finish_subvol(rctx);
1220 if (ret < 0)
1221 goto out;
1222
1223 iterations++;
1224 }
1225 ret = 0;
1226
1227 out:
1228 if (rctx->write_fd != -1) {
1229 close(rctx->write_fd);
1230 rctx->write_fd = -1;
1231 }
1232
1233 if (rctx->root_path != realmnt)
1234 free(rctx->root_path);
1235 rctx->root_path = NULL;
1236 rctx->dest_dir_path = NULL;
1237 free(dest_dir_full_path);
1238 subvol_uuid_search_finit(&rctx->sus);
1239 if (rctx->mnt_fd != -1) {
1240 close(rctx->mnt_fd);
1241 rctx->mnt_fd = -1;
1242 }
1243 if (rctx->dest_dir_fd != -1) {
1244 close(rctx->dest_dir_fd);
1245 rctx->dest_dir_fd = -1;
1246 }
1247
1248 return ret;
1249 }
1250
1251 int cmd_receive(int argc, char **argv)
1252 {
1253 char *tomnt = NULL;
1254 char fromfile[PATH_MAX];
1255 char realmnt[PATH_MAX];
1256 struct btrfs_receive rctx;
1257 int receive_fd = fileno(stdin);
1258 u64 max_errors = 1;
1259 int dump = 0;
1260 int ret = 0;
1261
1262 memset(&rctx, 0, sizeof(rctx));
1263 rctx.mnt_fd = -1;
1264 rctx.write_fd = -1;
1265 rctx.dest_dir_fd = -1;
1266 rctx.dest_dir_chroot = 0;
1267 realmnt[0] = 0;
1268 fromfile[0] = 0;
1269
1270 while (1) {
1271 int c;
1272 enum { GETOPT_VAL_DUMP = 257 };
1273 static const struct option long_opts[] = {
1274 { "max-errors", required_argument, NULL, 'E' },
1275 { "chroot", no_argument, NULL, 'C' },
1276 { "dump", no_argument, NULL, GETOPT_VAL_DUMP },
1277 { NULL, 0, NULL, 0 }
1278 };
1279
1280 c = getopt_long(argc, argv, "Cevf:m:E:", long_opts, NULL);
1281 if (c < 0)
1282 break;
1283
1284 switch (c) {
1285 case 'v':
1286 g_verbose++;
1287 break;
1288 case 'f':
1289 if (arg_copy_path(fromfile, optarg, sizeof(fromfile))) {
1290 error("input file path too long (%zu)",
1291 strlen(optarg));
1292 ret = 1;
1293 goto out;
1294 }
1295 break;
1296 case 'e':
1297 rctx.honor_end_cmd = 1;
1298 break;
1299 case 'C':
1300 rctx.dest_dir_chroot = 1;
1301 break;
1302 case 'E':
1303 max_errors = arg_strtou64(optarg);
1304 break;
1305 case 'm':
1306 if (arg_copy_path(realmnt, optarg, sizeof(realmnt))) {
1307 error("mount point path too long (%zu)",
1308 strlen(optarg));
1309 ret = 1;
1310 goto out;
1311 }
1312 break;
1313 case GETOPT_VAL_DUMP:
1314 dump = 1;
1315 break;
1316 case '?':
1317 default:
1318 error("receive args invalid");
1319 return 1;
1320 }
1321 }
1322
1323 if (dump && check_argc_exact(argc - optind, 0))
1324 usage(cmd_receive_usage);
1325 if (!dump && check_argc_exact(argc - optind, 1))
1326 usage(cmd_receive_usage);
1327
1328 tomnt = argv[optind];
1329
1330 if (fromfile[0]) {
1331 receive_fd = open(fromfile, O_RDONLY | O_NOATIME);
1332 if (receive_fd < 0) {
1333 error("cannot open %s: %s", fromfile, strerror(errno));
1334 goto out;
1335 }
1336 }
1337
1338 if (dump) {
1339 struct btrfs_dump_send_args dump_args;
1340
1341 dump_args.root_path[0] = '.';
1342 dump_args.root_path[1] = '\0';
1343 dump_args.full_subvol_path[0] = '.';
1344 dump_args.full_subvol_path[1] = '\0';
1345 ret = btrfs_read_and_process_send_stream(receive_fd,
1346 &btrfs_print_send_ops, &dump_args, 0, 0);
1347 if (ret < 0)
1348 error("failed to dump the send stream: %s",
1349 strerror(-ret));
1350 } else {
1351 ret = do_receive(&rctx, tomnt, realmnt, receive_fd, max_errors);
1352 }
1353
1354 if (receive_fd != fileno(stdin))
1355 close(receive_fd);
1356 out:
1357
1358 return !!ret;
1359 }
1360
1361 const char * const cmd_receive_usage[] = {
1362 "btrfs receive [options] <mount>\n"
1363 "btrfs receive --dump [options]",
1364 "Receive subvolumes from a stream",
1365 "Receives one or more subvolumes that were previously",
1366 "sent with btrfs send. The received subvolumes are stored",
1367 "into MOUNT.",
1368 "The receive will fail in case the receiving subvolume",
1369 "already exists. It will also fail in case a previously",
1370 "received subvolume has been changed after it was received.",
1371 "After receiving a subvolume, it is immediately set to",
1372 "read-only.",
1373 "",
1374 "-v increase verbosity about performed actions",
1375 "-f FILE read the stream from FILE instead of stdin",
1376 "-e terminate after receiving an <end cmd> marker in the stream.",
1377 " Without this option the receiver side terminates only in case",
1378 " of an error on end of file.",
1379 "-C|--chroot confine the process to <mount> using chroot",
1380 "-E|--max-errors NERR",
1381 " terminate as soon as NERR errors occur while",
1382 " stream processing commands from the stream.",
1383 " Default value is 1. A value of 0 means no limit.",
1384 "-m ROOTMOUNT the root mount point of the destination filesystem.",
1385 " If /proc is not accessible, use this to tell us where",
1386 " this file system is mounted.",
1387 "--dump dump stream metadata, one line per operation,",
1388 " does not require the MOUNT parameter",
1389 NULL
1390 };
(deprecated) Btrfs progs developments and patch integration