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Simplify the install of rsync-ssl by unifying 2 scripts.
[rsync.git] / xattrs.c
blob2afa3473d6a60aca47413c1f8cd4adb5034fe052
1 /*
2 * Extended Attribute support for rsync.
3 * Written by Jay Fenlason, vaguely based on the ACLs patch.
4 *
5 * Copyright (C) 2004 Red Hat, Inc.
6 * Copyright (C) 2006-2020 Wayne Davison
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 3 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, visit the http://fsf.org website.
20 */
21
22 #include "rsync.h"
23 #include "ifuncs.h"
24 #include "inums.h"
25 #include "lib/sysxattrs.h"
26
27 #ifdef SUPPORT_XATTRS
28
29 extern int dry_run;
30 extern int am_root;
31 extern int am_sender;
32 extern int am_generator;
33 extern int read_only;
34 extern int list_only;
35 extern int preserve_xattrs;
36 extern int preserve_links;
37 extern int preserve_devices;
38 extern int preserve_specials;
39 extern int checksum_seed;
40 extern int saw_xattr_filter;
41
42 #define RSYNC_XAL_INITIAL 5
43 #define RSYNC_XAL_LIST_INITIAL 100
44
45 #define MAX_FULL_DATUM 32
46
47 #define HAS_PREFIX(str, prfx) (*(str) == *(prfx) \
48 && strncmp(str, prfx, sizeof (prfx) - 1) == 0)
49
50 #define XATTR_ABBREV(x) ((size_t)((x).name - (x).datum) < (x).datum_len)
51
52 #define XSTATE_ABBREV 1
53 #define XSTATE_DONE 2
54 #define XSTATE_TODO 3
55
56 #define USER_PREFIX "user."
57 #define UPRE_LEN ((int)sizeof USER_PREFIX - 1)
58 #define SYSTEM_PREFIX "system."
59 #define SPRE_LEN ((int)sizeof SYSTEM_PREFIX - 1)
60
61 #ifdef HAVE_LINUX_XATTRS
62 #define MIGHT_NEED_RPRE (am_root < 0)
63 #define RSYNC_PREFIX USER_PREFIX "rsync."
64 #else
65 #define MIGHT_NEED_RPRE am_root
66 #define RSYNC_PREFIX "rsync."
67 #endif
68 #define RPRE_LEN ((int)sizeof RSYNC_PREFIX - 1)
69
70 #define XSTAT_SUFFIX "stat"
71 #define XSTAT_ATTR RSYNC_PREFIX "%" XSTAT_SUFFIX
72 #define XACC_ACL_SUFFIX "aacl"
73 #define XACC_ACL_ATTR RSYNC_PREFIX "%" XACC_ACL_SUFFIX
74 #define XDEF_ACL_SUFFIX "dacl"
75 #define XDEF_ACL_ATTR RSYNC_PREFIX "%" XDEF_ACL_SUFFIX
76
77 typedef struct {
78 char *datum, *name;
79 size_t datum_len, name_len;
80 int num;
81 } rsync_xa;
82
83 struct _rsync_xa_list;
84
85 typedef struct _rsync_xa_list_ref {
86 struct _rsync_xa_list_ref *next;
87 int ndx;
88 } rsync_xa_list_ref;
89
90 typedef struct _rsync_xa_list {
91 int ndx;
92 int64 key;
93 item_list xa_items;
94 } rsync_xa_list;
95
96 static size_t namebuf_len = 0;
97 static char *namebuf = NULL;
98
99 static const rsync_xa_list empty_xa_list = {
100 .xa_items = EMPTY_ITEM_LIST,
101 };
102 static const item_list empty_xattr = EMPTY_ITEM_LIST;
103 static item_list rsync_xal_l = EMPTY_ITEM_LIST;
104 static struct hashtable *rsync_xal_h = NULL;
105
106 static size_t prior_xattr_count = (size_t)-1;
107
108 /* ------------------------------------------------------------------------- */
109
110 static void rsync_xal_free(item_list *xalp)
111 {
112 size_t i;
113 rsync_xa *rxas = xalp->items;
114
115 if (!xalp->malloced)
116 return;
117
118 for (i = 0; i < xalp->count; i++) {
119 free(rxas[i].datum);
120 /*free(rxas[i].name);*/
121 }
122 free(xalp->items);
123 }
124
125 void free_xattr(stat_x *sxp)
126 {
127 if (!sxp->xattr)
128 return;
129 rsync_xal_free(sxp->xattr);
130 free(sxp->xattr);
131 sxp->xattr = NULL;
132 }
133
134 static int rsync_xal_compare_names(const void *x1, const void *x2)
135 {
136 const rsync_xa *xa1 = x1;
137 const rsync_xa *xa2 = x2;
138 return strcmp(xa1->name, xa2->name);
139 }
140
141 static ssize_t get_xattr_names(const char *fname)
142 {
143 ssize_t list_len;
144 int64 arg;
145
146 if (!namebuf) {
147 namebuf_len = 1024;
148 namebuf = new_array(char, namebuf_len);
149 if (!namebuf)
150 out_of_memory("get_xattr_names");
151 }
152
153 while (1) {
154 /* The length returned includes all the '\0' terminators. */
155 list_len = sys_llistxattr(fname, namebuf, namebuf_len);
156 if (list_len >= 0) {
157 if ((size_t)list_len <= namebuf_len)
158 break;
159 } else if (errno == ENOTSUP)
160 return 0;
161 else if (errno != ERANGE) {
162 arg = namebuf_len;
163 got_error:
164 rsyserr(FERROR_XFER, errno,
165 "get_xattr_names: llistxattr(%s,%s) failed",
166 full_fname(fname), big_num(arg));
167 return -1;
168 }
169 list_len = sys_llistxattr(fname, NULL, 0);
170 if (list_len < 0) {
171 arg = 0;
172 goto got_error;
173 }
174 if (namebuf_len)
175 free(namebuf);
176 namebuf_len = list_len + 1024;
177 namebuf = new_array(char, namebuf_len);
178 if (!namebuf)
179 out_of_memory("get_xattr_names");
180 }
181
182 return list_len;
183 }
184
185 /* On entry, the *len_ptr parameter contains the size of the extra space we
186 * should allocate when we create a buffer for the data. On exit, it contains
187 * the length of the datum. */
188 static char *get_xattr_data(const char *fname, const char *name, size_t *len_ptr,
189 int no_missing_error)
190 {
191 size_t datum_len = sys_lgetxattr(fname, name, NULL, 0);
192 size_t extra_len = *len_ptr;
193 char *ptr;
194
195 *len_ptr = datum_len;
196
197 if (datum_len == (size_t)-1) {
198 if (errno == ENOTSUP || no_missing_error)
199 return NULL;
200 rsyserr(FERROR_XFER, errno,
201 "get_xattr_data: lgetxattr(%s,\"%s\",0) failed",
202 full_fname(fname), name);
203 return NULL;
204 }
205
206 if (!datum_len && !extra_len)
207 extra_len = 1; /* request non-zero amount of memory */
208 if (datum_len + extra_len < datum_len)
209 overflow_exit("get_xattr_data");
210 if (!(ptr = new_array(char, datum_len + extra_len)))
211 out_of_memory("get_xattr_data");
212
213 if (datum_len) {
214 size_t len = sys_lgetxattr(fname, name, ptr, datum_len);
215 if (len != datum_len) {
216 if (len == (size_t)-1) {
217 rsyserr(FERROR_XFER, errno,
218 "get_xattr_data: lgetxattr(%s,\"%s\",%ld) failed",
219 full_fname(fname), name, (long)datum_len);
220 } else {
221 rprintf(FERROR_XFER,
222 "get_xattr_data: lgetxattr(%s,\"%s\",%ld) returned %ld\n",
223 full_fname(fname), name,
224 (long)datum_len, (long)len);
225 }
226 free(ptr);
227 return NULL;
228 }
229 }
230
231 return ptr;
232 }
233
234 static int rsync_xal_get(const char *fname, item_list *xalp)
235 {
236 ssize_t list_len, name_len;
237 size_t datum_len, name_offset;
238 char *name, *ptr;
239 #ifdef HAVE_LINUX_XATTRS
240 int user_only = am_sender ? 0 : !am_root;
241 #endif
242 rsync_xa *rxa;
243 int count;
244
245 /* This puts the name list into the "namebuf" buffer. */
246 if ((list_len = get_xattr_names(fname)) < 0)
247 return -1;
248
249 for (name = namebuf; list_len > 0; name += name_len) {
250 name_len = strlen(name) + 1;
251 list_len -= name_len;
252
253 if (saw_xattr_filter) {
254 if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS))
255 continue;
256 }
257 #ifdef HAVE_LINUX_XATTRS
258 /* Choose between ignoring the system namespace or (non-root) ignoring any non-user namespace. */
259 else if (user_only ? !HAS_PREFIX(name, USER_PREFIX) : HAS_PREFIX(name, SYSTEM_PREFIX))
260 continue;
261 #endif
262
263 /* No rsync.%FOO attributes are copied w/o 2 -X options. */
264 if (name_len > RPRE_LEN && name[RPRE_LEN] == '%' && HAS_PREFIX(name, RSYNC_PREFIX)) {
265 if ((am_sender && preserve_xattrs < 2)
266 || (am_root < 0
267 && (strcmp(name+RPRE_LEN+1, XSTAT_SUFFIX) == 0
268 || strcmp(name+RPRE_LEN+1, XACC_ACL_SUFFIX) == 0
269 || strcmp(name+RPRE_LEN+1, XDEF_ACL_SUFFIX) == 0)))
270 continue;
271 }
272
273 datum_len = name_len; /* Pass extra size to get_xattr_data() */
274 if (!(ptr = get_xattr_data(fname, name, &datum_len, 0)))
275 return -1;
276
277 if (datum_len > MAX_FULL_DATUM) {
278 /* For large datums, we store a flag and a checksum. */
279 name_offset = 1 + MAX_DIGEST_LEN;
280 sum_init(-1, checksum_seed);
281 sum_update(ptr, datum_len);
282 free(ptr);
283
284 if (!(ptr = new_array(char, name_offset + name_len)))
285 out_of_memory("rsync_xal_get");
286 *ptr = XSTATE_ABBREV;
287 sum_end(ptr + 1);
288 } else
289 name_offset = datum_len;
290
291 rxa = EXPAND_ITEM_LIST(xalp, rsync_xa, RSYNC_XAL_INITIAL);
292 rxa->name = ptr + name_offset;
293 memcpy(rxa->name, name, name_len);
294 rxa->datum = ptr;
295 rxa->name_len = name_len;
296 rxa->datum_len = datum_len;
297 }
298 count = xalp->count;
299 rxa = xalp->items;
300 if (count > 1)
301 qsort(rxa, count, sizeof (rsync_xa), rsync_xal_compare_names);
302 for (rxa += count-1; count; count--, rxa--)
303 rxa->num = count;
304 return 0;
305 }
306
307 /* Read the xattr(s) for this filename. */
308 int get_xattr(const char *fname, stat_x *sxp)
309 {
310 sxp->xattr = new(item_list);
311 *sxp->xattr = empty_xattr;
312
313 if (S_ISREG(sxp->st.st_mode) || S_ISDIR(sxp->st.st_mode)) {
314 /* Everyone supports this. */
315 } else if (S_ISLNK(sxp->st.st_mode)) {
316 #ifndef NO_SYMLINK_XATTRS
317 if (!preserve_links)
318 #endif
319 return 0;
320 } else if (IS_SPECIAL(sxp->st.st_mode)) {
321 #ifndef NO_SPECIAL_XATTRS
322 if (!preserve_specials)
323 #endif
324 return 0;
325 } else if (IS_DEVICE(sxp->st.st_mode)) {
326 #ifndef NO_DEVICE_XATTRS
327 if (!preserve_devices)
328 #endif
329 return 0;
330 } else if (IS_MISSING_FILE(sxp->st))
331 return 0;
332
333 if (rsync_xal_get(fname, sxp->xattr) < 0) {
334 free_xattr(sxp);
335 return -1;
336 }
337 return 0;
338 }
339
340 int copy_xattrs(const char *source, const char *dest)
341 {
342 ssize_t list_len, name_len;
343 size_t datum_len;
344 char *name, *ptr;
345 #ifdef HAVE_LINUX_XATTRS
346 int user_only = am_sender ? 0 : am_root <= 0;
347 #endif
348
349 /* This puts the name list into the "namebuf" buffer. */
350 if ((list_len = get_xattr_names(source)) < 0)
351 return -1;
352
353 for (name = namebuf; list_len > 0; name += name_len) {
354 name_len = strlen(name) + 1;
355 list_len -= name_len;
356
357 if (saw_xattr_filter) {
358 if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS))
359 continue;
360 }
361 #ifdef HAVE_LINUX_XATTRS
362 /* Choose between ignoring the system namespace or (non-root) ignoring any non-user namespace. */
363 else if (user_only ? !HAS_PREFIX(name, USER_PREFIX) : HAS_PREFIX(name, SYSTEM_PREFIX))
364 continue;
365 #endif
366
367 datum_len = 0;
368 if (!(ptr = get_xattr_data(source, name, &datum_len, 0)))
369 return -1;
370 if (sys_lsetxattr(dest, name, ptr, datum_len) < 0) {
371 int save_errno = errno ? errno : EINVAL;
372 rsyserr(FERROR_XFER, errno,
373 "copy_xattrs: lsetxattr(%s,\"%s\") failed",
374 full_fname(dest), name);
375 errno = save_errno;
376 return -1;
377 }
378 free(ptr);
379 }
380
381 return 0;
382 }
383
384 static int64 xattr_lookup_hash(const item_list *xalp)
385 {
386 const rsync_xa *rxas = xalp->items;
387 size_t i;
388 int64 key = hashlittle(&xalp->count, sizeof xalp->count);
389
390 for (i = 0; i < xalp->count; i++) {
391 key += hashlittle(rxas[i].name, rxas[i].name_len);
392 if (rxas[i].datum_len > MAX_FULL_DATUM)
393 key += hashlittle(rxas[i].datum, MAX_DIGEST_LEN);
394 else
395 key += hashlittle(rxas[i].datum, rxas[i].datum_len);
396 }
397
398 if (key == 0) {
399 /* This is very unlikely, but we should never
400 * return 0 as hashtable_find() doesn't like it. */
401 return 1;
402 }
403
404 return key;
405 }
406
407 static int find_matching_xattr(const item_list *xalp)
408 {
409 const struct ht_int64_node *node;
410 const rsync_xa_list_ref *ref;
411 int64 key;
412
413 if (rsync_xal_h == NULL)
414 return -1;
415
416 key = xattr_lookup_hash(xalp);
417
418 node = hashtable_find(rsync_xal_h, key, 0);
419 if (node == NULL)
420 return -1;
421
422 if (node->data == NULL)
423 return -1;
424
425 for (ref = node->data; ref != NULL; ref = ref->next) {
426 const rsync_xa_list *ptr = rsync_xal_l.items;
427 const rsync_xa *rxas1;
428 const rsync_xa *rxas2 = xalp->items;
429 size_t j;
430
431 ptr += ref->ndx;
432 rxas1 = ptr->xa_items.items;
433
434 /* Wrong number of elements? */
435 if (ptr->xa_items.count != xalp->count)
436 continue;
437 /* any elements different? */
438 for (j = 0; j < xalp->count; j++) {
439 if (rxas1[j].name_len != rxas2[j].name_len
440 || rxas1[j].datum_len != rxas2[j].datum_len
441 || strcmp(rxas1[j].name, rxas2[j].name))
442 break;
443 if (rxas1[j].datum_len > MAX_FULL_DATUM) {
444 if (memcmp(rxas1[j].datum + 1,
445 rxas2[j].datum + 1,
446 MAX_DIGEST_LEN) != 0)
447 break;
448 } else {
449 if (memcmp(rxas1[j].datum, rxas2[j].datum,
450 rxas2[j].datum_len))
451 break;
452 }
453 }
454 /* no differences found. This is The One! */
455 if (j == xalp->count)
456 return ref->ndx;
457 }
458
459 return -1;
460 }
461
462 /* Store *xalp on the end of rsync_xal_l */
463 static int rsync_xal_store(item_list *xalp)
464 {
465 struct ht_int64_node *node;
466 int ndx = rsync_xal_l.count; /* pre-incremented count */
467 rsync_xa_list *new_list = EXPAND_ITEM_LIST(&rsync_xal_l, rsync_xa_list, RSYNC_XAL_LIST_INITIAL);
468 rsync_xa_list_ref *new_ref;
469 /* Since the following call starts a new list, we know it will hold the
470 * entire initial-count, not just enough space for one new item. */
471 *new_list = empty_xa_list;
472 (void)EXPAND_ITEM_LIST(&new_list->xa_items, rsync_xa, xalp->count);
473 memcpy(new_list->xa_items.items, xalp->items, xalp->count * sizeof (rsync_xa));
474 new_list->xa_items.count = xalp->count;
475 xalp->count = 0;
476
477 new_list->ndx = ndx;
478 new_list->key = xattr_lookup_hash(&new_list->xa_items);
479
480 if (rsync_xal_h == NULL)
481 rsync_xal_h = hashtable_create(512, 1);
482 if (rsync_xal_h == NULL)
483 out_of_memory("rsync_xal_h hashtable_create()");
484
485 node = hashtable_find(rsync_xal_h, new_list->key, 1);
486 if (node == NULL)
487 out_of_memory("rsync_xal_h hashtable_find()");
488
489 new_ref = new0(rsync_xa_list_ref);
490 if (new_ref == NULL)
491 out_of_memory("new0(rsync_xa_list_ref)");
492
493 new_ref->ndx = ndx;
494
495 if (node->data != NULL) {
496 rsync_xa_list_ref *ref = node->data;
497
498 while (ref != NULL) {
499 if (ref->next != NULL) {
500 ref = ref->next;
501 continue;
502 }
503
504 ref->next = new_ref;
505 break;
506 }
507 } else
508 node->data = new_ref;
509
510 return ndx;
511 }
512
513 /* Send the make_xattr()-generated xattr list for this flist entry. */
514 int send_xattr(int f, stat_x *sxp)
515 {
516 int ndx = find_matching_xattr(sxp->xattr);
517
518 /* Send 0 (-1 + 1) to indicate that literal xattr data follows. */
519 write_varint(f, ndx + 1);
520
521 if (ndx < 0) {
522 rsync_xa *rxa;
523 int count = sxp->xattr->count;
524 write_varint(f, count);
525 for (rxa = sxp->xattr->items; count--; rxa++) {
526 size_t name_len = rxa->name_len;
527 const char *name = rxa->name;
528 /* Strip the rsync prefix from disguised namespaces. */
529 if (name_len > RPRE_LEN
530 #ifdef HAVE_LINUX_XATTRS
531 && am_root < 0
532 #endif
533 && name[RPRE_LEN] != '%' && HAS_PREFIX(name, RSYNC_PREFIX)) {
534 name += RPRE_LEN;
535 name_len -= RPRE_LEN;
536 }
537 #ifndef HAVE_LINUX_XATTRS
538 else {
539 /* Put everything else in the user namespace. */
540 name_len += UPRE_LEN;
541 }
542 #endif
543 write_varint(f, name_len);
544 write_varint(f, rxa->datum_len);
545 #ifndef HAVE_LINUX_XATTRS
546 if (name_len > rxa->name_len) {
547 write_buf(f, USER_PREFIX, UPRE_LEN);
548 name_len -= UPRE_LEN;
549 }
550 #endif
551 write_buf(f, name, name_len);
552 if (rxa->datum_len > MAX_FULL_DATUM)
553 write_buf(f, rxa->datum + 1, MAX_DIGEST_LEN);
554 else
555 write_bigbuf(f, rxa->datum, rxa->datum_len);
556 }
557 ndx = rsync_xal_store(sxp->xattr); /* adds item to rsync_xal_l */
558 }
559
560 return ndx;
561 }
562
563 /* Return a flag indicating if we need to change a file's xattrs. If
564 * "find_all" is specified, also mark any abbreviated xattrs that we
565 * need so that send_xattr_request() can tell the sender about them. */
566 int xattr_diff(struct file_struct *file, stat_x *sxp, int find_all)
567 {
568 const rsync_xa_list *glst = rsync_xal_l.items;
569 const item_list *lst;
570 rsync_xa *snd_rxa, *rec_rxa;
571 int snd_cnt, rec_cnt;
572 int cmp, same, xattrs_equal = 1;
573
574 if (sxp && XATTR_READY(*sxp)) {
575 rec_rxa = sxp->xattr->items;
576 rec_cnt = sxp->xattr->count;
577 } else {
578 rec_rxa = NULL;
579 rec_cnt = 0;
580 }
581
582 if (F_XATTR(file) >= 0) {
583 glst += F_XATTR(file);
584 lst = &glst->xa_items;
585 } else
586 lst = &empty_xattr;
587
588 snd_rxa = lst->items;
589 snd_cnt = lst->count;
590
591 /* If the count of the sender's xattrs is different from our
592 * (receiver's) xattrs, the lists are not the same. */
593 if (snd_cnt != rec_cnt) {
594 if (!find_all)
595 return 1;
596 xattrs_equal = 0;
597 }
598
599 while (snd_cnt) {
600 cmp = rec_cnt ? strcmp(snd_rxa->name, rec_rxa->name) : -1;
601 if (cmp > 0)
602 same = 0;
603 else if (snd_rxa->datum_len > MAX_FULL_DATUM) {
604 same = cmp == 0 && snd_rxa->datum_len == rec_rxa->datum_len
605 && memcmp(snd_rxa->datum + 1, rec_rxa->datum + 1,
606 MAX_DIGEST_LEN) == 0;
607 /* Flag unrequested items that we need. */
608 if (!same && find_all && snd_rxa->datum[0] == XSTATE_ABBREV)
609 snd_rxa->datum[0] = XSTATE_TODO;
610 } else {
611 same = cmp == 0 && snd_rxa->datum_len == rec_rxa->datum_len
612 && memcmp(snd_rxa->datum, rec_rxa->datum,
613 snd_rxa->datum_len) == 0;
614 }
615 if (!same) {
616 if (!find_all)
617 return 1;
618 xattrs_equal = 0;
619 }
620
621 if (cmp <= 0) {
622 snd_rxa++;
623 snd_cnt--;
624 }
625 if (cmp >= 0) {
626 rec_rxa++;
627 rec_cnt--;
628 }
629 }
630
631 if (rec_cnt)
632 xattrs_equal = 0;
633
634 return !xattrs_equal;
635 }
636
637 /* When called by the generator (with a NULL fname), this tells the sender
638 * all the abbreviated xattr values we need. When called by the sender
639 * (with a non-NULL fname), we send all the extra xattr data it needs.
640 * The generator may also call with f_out < 0 to just change all the
641 * XSTATE_ABBREV states into XSTATE_DONE. */
642 void send_xattr_request(const char *fname, struct file_struct *file, int f_out)
643 {
644 const rsync_xa_list *glst = rsync_xal_l.items;
645 const item_list *lst;
646 int cnt, prior_req = 0;
647 rsync_xa *rxa;
648
649 glst += F_XATTR(file);
650 lst = &glst->xa_items;
651
652 for (rxa = lst->items, cnt = lst->count; cnt--; rxa++) {
653 if (rxa->datum_len <= MAX_FULL_DATUM)
654 continue;
655 switch (rxa->datum[0]) {
656 case XSTATE_ABBREV:
657 /* Items left abbreviated matched the sender's checksum, so
658 * the receiver will cache the local data for future use. */
659 if (am_generator)
660 rxa->datum[0] = XSTATE_DONE;
661 continue;
662 case XSTATE_TODO:
663 assert(f_out >= 0);
664 break;
665 default:
666 continue;
667 }
668
669 /* Flag that we handled this abbreviated item. */
670 rxa->datum[0] = XSTATE_DONE;
671
672 write_varint(f_out, rxa->num - prior_req);
673 prior_req = rxa->num;
674
675 if (fname) {
676 size_t len = 0;
677 char *ptr;
678
679 /* Re-read the long datum. */
680 if (!(ptr = get_xattr_data(fname, rxa->name, &len, 0))) {
681 rprintf(FERROR_XFER, "failed to re-read xattr %s for %s\n", rxa->name, fname);
682 write_varint(f_out, 0);
683 continue;
684 }
685
686 write_varint(f_out, len); /* length might have changed! */
687 write_bigbuf(f_out, ptr, len);
688 free(ptr);
689 }
690 }
691
692 if (f_out >= 0)
693 write_byte(f_out, 0); /* end the list */
694 }
695
696 /* When called by the sender, read the request from the generator and mark
697 * any needed xattrs with a flag that lets us know they need to be sent to
698 * the receiver. When called by the receiver, reads the sent data and
699 * stores it in place of its checksum. */
700 int recv_xattr_request(struct file_struct *file, int f_in)
701 {
702 const rsync_xa_list *glst = rsync_xal_l.items;
703 const item_list *lst;
704 char *old_datum, *name;
705 rsync_xa *rxa;
706 int rel_pos, cnt, num, got_xattr_data = 0;
707
708 if (F_XATTR(file) < 0) {
709 rprintf(FERROR, "recv_xattr_request: internal data error!\n");
710 exit_cleanup(RERR_PROTOCOL);
711 }
712 glst += F_XATTR(file);
713 lst = &glst->xa_items;
714
715 cnt = lst->count;
716 rxa = lst->items;
717 num = 0;
718 while ((rel_pos = read_varint(f_in)) != 0) {
719 num += rel_pos;
720 if (am_sender) {
721 /* The sender-related num values are only in order on the sender.
722 * We use that order here to scan forward or backward as needed. */
723 if (rel_pos < 0) {
724 while (cnt < (int)lst->count && rxa->num > num) {
725 rxa--;
726 cnt++;
727 }
728 } else {
729 while (cnt > 1 && rxa->num < num) {
730 rxa++;
731 cnt--;
732 }
733 }
734 } else {
735 int j;
736 /* The receiving side has no known num order, so we just scan
737 * forward (w/wrap) and hope that the next value is near by. */
738 for (j = lst->count; j > 1 && rxa->num != num; j--) {
739 if (--cnt)
740 rxa++;
741 else {
742 cnt = lst->count;
743 rxa = lst->items;
744 }
745 }
746 }
747 if (!cnt || rxa->num != num) {
748 rprintf(FERROR, "[%s] could not find xattr #%d for %s\n",
749 who_am_i(), num, f_name(file, NULL));
750 exit_cleanup(RERR_PROTOCOL);
751 }
752 if (!XATTR_ABBREV(*rxa) || rxa->datum[0] != XSTATE_ABBREV) {
753 rprintf(FERROR, "[%s] internal abbrev error on %s (%s, len=%ld)!\n",
754 who_am_i(), f_name(file, NULL), rxa->name, (long)rxa->datum_len);
755 exit_cleanup(RERR_PROTOCOL);
756 }
757
758 if (am_sender) {
759 rxa->datum[0] = XSTATE_TODO;
760 continue;
761 }
762
763 old_datum = rxa->datum;
764 rxa->datum_len = read_varint(f_in);
765
766 if (rxa->name_len + rxa->datum_len < rxa->name_len)
767 overflow_exit("recv_xattr_request");
768 rxa->datum = new_array(char, rxa->datum_len + rxa->name_len);
769 if (!rxa->datum)
770 out_of_memory("recv_xattr_request");
771 name = rxa->datum + rxa->datum_len;
772 memcpy(name, rxa->name, rxa->name_len);
773 rxa->name = name;
774 free(old_datum);
775 read_buf(f_in, rxa->datum, rxa->datum_len);
776 got_xattr_data = 1;
777 }
778
779 return got_xattr_data;
780 }
781
782 /* ------------------------------------------------------------------------- */
783
784 /* receive and build the rsync_xattr_lists */
785 void receive_xattr(int f, struct file_struct *file)
786 {
787 static item_list temp_xattr = EMPTY_ITEM_LIST;
788 int count, num;
789 #ifdef HAVE_LINUX_XATTRS
790 int need_sort = 0;
791 #else
792 int need_sort = 1;
793 #endif
794 int ndx = read_varint(f);
795
796 if (ndx < 0 || (size_t)ndx > rsync_xal_l.count) {
797 rprintf(FERROR, "receive_xattr: xa index %d out of"
798 " range for %s\n", ndx, f_name(file, NULL));
799 exit_cleanup(RERR_STREAMIO);
800 }
801
802 if (ndx != 0) {
803 F_XATTR(file) = ndx - 1;
804 return;
805 }
806
807 if ((count = read_varint(f)) != 0) {
808 (void)EXPAND_ITEM_LIST(&temp_xattr, rsync_xa, count);
809 temp_xattr.count = 0;
810 }
811
812 for (num = 1; num <= count; num++) {
813 char *ptr, *name;
814 rsync_xa *rxa;
815 size_t name_len = read_varint(f);
816 size_t datum_len = read_varint(f);
817 size_t dget_len = datum_len > MAX_FULL_DATUM ? 1 + MAX_DIGEST_LEN : datum_len;
818 size_t extra_len = MIGHT_NEED_RPRE ? RPRE_LEN : 0;
819 if ((dget_len + extra_len < dget_len)
820 || (dget_len + extra_len + name_len < dget_len + extra_len))
821 overflow_exit("receive_xattr");
822 ptr = new_array(char, dget_len + extra_len + name_len);
823 if (!ptr)
824 out_of_memory("receive_xattr");
825 name = ptr + dget_len + extra_len;
826 read_buf(f, name, name_len);
827 if (name_len < 1 || name[name_len-1] != '\0') {
828 rprintf(FERROR, "Invalid xattr name received (missing trailing \\0).\n");
829 exit_cleanup(RERR_FILEIO);
830 }
831 if (dget_len == datum_len)
832 read_buf(f, ptr, dget_len);
833 else {
834 *ptr = XSTATE_ABBREV;
835 read_buf(f, ptr + 1, MAX_DIGEST_LEN);
836 }
837
838 if (saw_xattr_filter) {
839 if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS)) {
840 free(ptr);
841 continue;
842 }
843 }
844 #ifdef HAVE_LINUX_XATTRS
845 /* Non-root can only save the user namespace. */
846 if (am_root <= 0 && !HAS_PREFIX(name, USER_PREFIX)) {
847 if (!am_root && !saw_xattr_filter) {
848 free(ptr);
849 continue;
850 }
851 name -= RPRE_LEN;
852 name_len += RPRE_LEN;
853 memcpy(name, RSYNC_PREFIX, RPRE_LEN);
854 need_sort = 1;
855 }
856 #else
857 /* This OS only has a user namespace, so we either
858 * strip the user prefix, or we put a non-user
859 * namespace inside our rsync hierarchy. */
860 if (HAS_PREFIX(name, USER_PREFIX)) {
861 name += UPRE_LEN;
862 name_len -= UPRE_LEN;
863 } else if (am_root) {
864 name -= RPRE_LEN;
865 name_len += RPRE_LEN;
866 memcpy(name, RSYNC_PREFIX, RPRE_LEN);
867 } else {
868 free(ptr);
869 continue;
870 }
871 #endif
872 /* No rsync.%FOO attributes are copied w/o 2 -X options. */
873 if (preserve_xattrs < 2 && name_len > RPRE_LEN
874 && name[RPRE_LEN] == '%' && HAS_PREFIX(name, RSYNC_PREFIX)) {
875 free(ptr);
876 continue;
877 }
878
879 rxa = EXPAND_ITEM_LIST(&temp_xattr, rsync_xa, 1);
880 rxa->name = name;
881 rxa->datum = ptr;
882 rxa->name_len = name_len;
883 rxa->datum_len = datum_len;
884 rxa->num = num;
885 }
886
887 if (need_sort && count > 1)
888 qsort(temp_xattr.items, count, sizeof (rsync_xa), rsync_xal_compare_names);
889
890 ndx = rsync_xal_store(&temp_xattr); /* adds item to rsync_xal_l */
891
892 F_XATTR(file) = ndx;
893 }
894
895 /* Turn the xattr data in stat_x into cached xattr data, setting the index
896 * values in the file struct. */
897 void cache_tmp_xattr(struct file_struct *file, stat_x *sxp)
898 {
899 int ndx;
900
901 if (!sxp->xattr)
902 return;
903
904 if (prior_xattr_count == (size_t)-1)
905 prior_xattr_count = rsync_xal_l.count;
906 ndx = find_matching_xattr(sxp->xattr);
907 if (ndx < 0)
908 rsync_xal_store(sxp->xattr); /* adds item to rsync_xal_l */
909
910 F_XATTR(file) = ndx;
911 }
912
913 void uncache_tmp_xattrs(void)
914 {
915 if (prior_xattr_count != (size_t)-1) {
916 rsync_xa_list *xa_list_item = rsync_xal_l.items;
917 rsync_xa_list *xa_list_start = xa_list_item + prior_xattr_count;
918 xa_list_item += rsync_xal_l.count;
919 rsync_xal_l.count = prior_xattr_count;
920 while (xa_list_item-- > xa_list_start) {
921 struct ht_int64_node *node;
922 rsync_xa_list_ref *ref;
923
924 rsync_xal_free(&xa_list_item->xa_items);
925
926 if (rsync_xal_h == NULL)
927 continue;
928
929 node = hashtable_find(rsync_xal_h, xa_list_item->key, 0);
930 if (node == NULL)
931 continue;
932
933 if (node->data == NULL)
934 continue;
935
936 ref = node->data;
937 if (xa_list_item->ndx == ref->ndx) {
938 /* xa_list_item is the first in the list. */
939 node->data = ref->next;
940 free(ref);
941 continue;
942 }
943
944 while (ref != NULL) {
945 if (ref->next == NULL) {
946 ref = NULL;
947 break;
948 }
949 if (xa_list_item->ndx == ref->next->ndx) {
950 ref->next = ref->next->next;
951 free(ref);
952 break;
953 }
954 ref = ref->next;
955 }
956 }
957 prior_xattr_count = (size_t)-1;
958 }
959 }
960
961 static int rsync_xal_set(const char *fname, item_list *xalp,
962 const char *fnamecmp, stat_x *sxp)
963 {
964 rsync_xa *rxas = xalp->items;
965 ssize_t list_len;
966 size_t i, len;
967 char *name, *ptr, sum[MAX_DIGEST_LEN];
968 #ifdef HAVE_LINUX_XATTRS
969 int user_only = am_root <= 0;
970 #endif
971 size_t name_len;
972 int ret = 0;
973
974 /* This puts the current name list into the "namebuf" buffer. */
975 if ((list_len = get_xattr_names(fname)) < 0)
976 return -1;
977
978 for (i = 0; i < xalp->count; i++) {
979 name = rxas[i].name;
980
981 if (XATTR_ABBREV(rxas[i])) {
982 int sum_len;
983 /* See if the fnamecmp version is identical. */
984 len = name_len = rxas[i].name_len;
985 if ((ptr = get_xattr_data(fnamecmp, name, &len, 1)) == NULL) {
986 still_abbrev:
987 if (am_generator)
988 continue;
989 rprintf(FERROR, "Missing abbreviated xattr value, %s, for %s\n",
990 rxas[i].name, full_fname(fname));
991 ret = -1;
992 continue;
993 }
994 if (len != rxas[i].datum_len) {
995 free(ptr);
996 goto still_abbrev;
997 }
998
999 sum_init(-1, checksum_seed);
1000 sum_update(ptr, len);
1001 sum_len = sum_end(sum);
1002 if (memcmp(sum, rxas[i].datum + 1, sum_len) != 0) {
1003 free(ptr);
1004 goto still_abbrev;
1005 }
1006
1007 if (fname == fnamecmp)
1008 ; /* Value is already set when identical */
1009 else if (sys_lsetxattr(fname, name, ptr, len) < 0) {
1010 rsyserr(FERROR_XFER, errno,
1011 "rsync_xal_set: lsetxattr(%s,\"%s\") failed",
1012 full_fname(fname), name);
1013 ret = -1;
1014 } else /* make sure caller sets mtime */
1015 sxp->st.st_mtime = (time_t)-1;
1016
1017 if (am_generator) { /* generator items stay abbreviated */
1018 free(ptr);
1019 continue;
1020 }
1021
1022 memcpy(ptr + len, name, name_len);
1023 free(rxas[i].datum);
1024
1025 rxas[i].name = name = ptr + len;
1026 rxas[i].datum = ptr;
1027 continue;
1028 }
1029
1030 if (sys_lsetxattr(fname, name, rxas[i].datum, rxas[i].datum_len) < 0) {
1031 rsyserr(FERROR_XFER, errno,
1032 "rsync_xal_set: lsetxattr(%s,\"%s\") failed",
1033 full_fname(fname), name);
1034 ret = -1;
1035 } else /* make sure caller sets mtime */
1036 sxp->st.st_mtime = (time_t)-1;
1037 }
1038
1039 /* Remove any extraneous names. */
1040 for (name = namebuf; list_len > 0; name += name_len) {
1041 name_len = strlen(name) + 1;
1042 list_len -= name_len;
1043
1044 if (saw_xattr_filter) {
1045 if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS))
1046 continue;
1047 }
1048 #ifdef HAVE_LINUX_XATTRS
1049 /* Choose between ignoring the system namespace or (non-root) ignoring any non-user namespace. */
1050 else if (user_only ? !HAS_PREFIX(name, USER_PREFIX) : HAS_PREFIX(name, SYSTEM_PREFIX))
1051 continue;
1052 #endif
1053 if (am_root < 0 && name_len > RPRE_LEN && name[RPRE_LEN] == '%' && strcmp(name, XSTAT_ATTR) == 0)
1054 continue;
1055
1056 for (i = 0; i < xalp->count; i++) {
1057 if (strcmp(name, rxas[i].name) == 0)
1058 break;
1059 }
1060 if (i == xalp->count) {
1061 if (sys_lremovexattr(fname, name) < 0) {
1062 rsyserr(FERROR_XFER, errno,
1063 "rsync_xal_set: lremovexattr(%s,\"%s\") failed",
1064 full_fname(fname), name);
1065 ret = -1;
1066 } else /* make sure caller sets mtime */
1067 sxp->st.st_mtime = (time_t)-1;
1068 }
1069 }
1070
1071 return ret;
1072 }
1073
1074 /* Set extended attributes on indicated filename. */
1075 int set_xattr(const char *fname, const struct file_struct *file,
1076 const char *fnamecmp, stat_x *sxp)
1077 {
1078 rsync_xa_list *glst = rsync_xal_l.items;
1079 item_list *lst;
1080 int ndx;
1081
1082 if (dry_run)
1083 return 1; /* FIXME: --dry-run needs to compute this value */
1084
1085 if (read_only || list_only) {
1086 errno = EROFS;
1087 return -1;
1088 }
1089
1090 #ifdef NO_SPECIAL_XATTRS
1091 if (IS_SPECIAL(sxp->st.st_mode)) {
1092 errno = ENOTSUP;
1093 return -1;
1094 }
1095 #endif
1096 #ifdef NO_DEVICE_XATTRS
1097 if (IS_DEVICE(sxp->st.st_mode)) {
1098 errno = ENOTSUP;
1099 return -1;
1100 }
1101 #endif
1102 #ifdef NO_SYMLINK_XATTRS
1103 if (S_ISLNK(sxp->st.st_mode)) {
1104 errno = ENOTSUP;
1105 return -1;
1106 }
1107 #endif
1108
1109 ndx = F_XATTR(file);
1110 glst += ndx;
1111 lst = &glst->xa_items;
1112 return rsync_xal_set(fname, lst, fnamecmp, sxp);
1113 }
1114
1115 #ifdef SUPPORT_ACLS
1116 char *get_xattr_acl(const char *fname, int is_access_acl, size_t *len_p)
1117 {
1118 const char *name = is_access_acl ? XACC_ACL_ATTR : XDEF_ACL_ATTR;
1119 *len_p = 0; /* no extra data alloc needed from get_xattr_data() */
1120 return get_xattr_data(fname, name, len_p, 1);
1121 }
1122
1123 int set_xattr_acl(const char *fname, int is_access_acl, const char *buf, size_t buf_len)
1124 {
1125 const char *name = is_access_acl ? XACC_ACL_ATTR : XDEF_ACL_ATTR;
1126 if (sys_lsetxattr(fname, name, buf, buf_len) < 0) {
1127 rsyserr(FERROR_XFER, errno,
1128 "set_xattr_acl: lsetxattr(%s,\"%s\") failed",
1129 full_fname(fname), name);
1130 return -1;
1131 }
1132 return 0;
1133 }
1134
1135 int del_def_xattr_acl(const char *fname)
1136 {
1137 return sys_lremovexattr(fname, XDEF_ACL_ATTR);
1138 }
1139 #endif
1140
1141 int get_stat_xattr(const char *fname, int fd, STRUCT_STAT *fst, STRUCT_STAT *xst)
1142 {
1143 int mode, rdev_major, rdev_minor, uid, gid, len;
1144 char buf[256];
1145
1146 if (am_root >= 0 || IS_DEVICE(fst->st_mode) || IS_SPECIAL(fst->st_mode))
1147 return -1;
1148
1149 if (xst)
1150 *xst = *fst;
1151 else
1152 xst = fst;
1153 if (fname) {
1154 fd = -1;
1155 len = sys_lgetxattr(fname, XSTAT_ATTR, buf, sizeof buf - 1);
1156 } else {
1157 fname = "fd";
1158 len = sys_fgetxattr(fd, XSTAT_ATTR, buf, sizeof buf - 1);
1159 }
1160 if (len >= (int)sizeof buf) {
1161 len = -1;
1162 errno = ERANGE;
1163 }
1164 if (len < 0) {
1165 if (errno == ENOTSUP || errno == ENOATTR)
1166 return -1;
1167 if (errno == EPERM && S_ISLNK(fst->st_mode)) {
1168 xst->st_uid = 0;
1169 xst->st_gid = 0;
1170 return 0;
1171 }
1172 rsyserr(FERROR_XFER, errno, "failed to read xattr %s for %s",
1173 XSTAT_ATTR, full_fname(fname));
1174 return -1;
1175 }
1176 buf[len] = '\0';
1177
1178 if (sscanf(buf, "%o %d,%d %d:%d",
1179 &mode, &rdev_major, &rdev_minor, &uid, &gid) != 5) {
1180 rprintf(FERROR, "Corrupt %s xattr attached to %s: \"%s\"\n",
1181 XSTAT_ATTR, full_fname(fname), buf);
1182 exit_cleanup(RERR_FILEIO);
1183 }
1184
1185 xst->st_mode = from_wire_mode(mode);
1186 xst->st_rdev = MAKEDEV(rdev_major, rdev_minor);
1187 xst->st_uid = uid;
1188 xst->st_gid = gid;
1189
1190 return 0;
1191 }
1192
1193 int set_stat_xattr(const char *fname, struct file_struct *file, mode_t new_mode)
1194 {
1195 STRUCT_STAT fst, xst;
1196 dev_t rdev;
1197 mode_t mode, fmode;
1198
1199 if (dry_run)
1200 return 0;
1201
1202 if (read_only || list_only) {
1203 rsyserr(FERROR_XFER, EROFS, "failed to write xattr %s for %s",
1204 XSTAT_ATTR, full_fname(fname));
1205 return -1;
1206 }
1207
1208 if (x_lstat(fname, &fst, &xst) < 0) {
1209 rsyserr(FERROR_XFER, errno, "failed to re-stat %s",
1210 full_fname(fname));
1211 return -1;
1212 }
1213
1214 fst.st_mode &= (_S_IFMT | CHMOD_BITS);
1215 fmode = new_mode & (_S_IFMT | CHMOD_BITS);
1216
1217 if (IS_DEVICE(fmode)) {
1218 uint32 *devp = F_RDEV_P(file);
1219 rdev = MAKEDEV(DEV_MAJOR(devp), DEV_MINOR(devp));
1220 } else
1221 rdev = 0;
1222
1223 /* Dump the special permissions and enable full owner access. */
1224 mode = (fst.st_mode & _S_IFMT) | (fmode & ACCESSPERMS)
1225 | (S_ISDIR(fst.st_mode) ? 0700 : 0600);
1226 if (fst.st_mode != mode)
1227 do_chmod(fname, mode);
1228 if (!IS_DEVICE(fst.st_mode))
1229 fst.st_rdev = 0; /* just in case */
1230
1231 if (mode == fmode && fst.st_rdev == rdev
1232 && fst.st_uid == F_OWNER(file) && fst.st_gid == F_GROUP(file)) {
1233 /* xst.st_mode will be 0 if there's no current stat xattr */
1234 if (xst.st_mode && sys_lremovexattr(fname, XSTAT_ATTR) < 0) {
1235 rsyserr(FERROR_XFER, errno,
1236 "delete of stat xattr failed for %s",
1237 full_fname(fname));
1238 return -1;
1239 }
1240 return 0;
1241 }
1242
1243 if (xst.st_mode != fmode || xst.st_rdev != rdev
1244 || xst.st_uid != F_OWNER(file) || xst.st_gid != F_GROUP(file)) {
1245 char buf[256];
1246 int len = snprintf(buf, sizeof buf, "%o %u,%u %u:%u",
1247 to_wire_mode(fmode),
1248 (int)major(rdev), (int)minor(rdev),
1249 F_OWNER(file), F_GROUP(file));
1250 if (sys_lsetxattr(fname, XSTAT_ATTR, buf, len) < 0) {
1251 if (errno == EPERM && S_ISLNK(fst.st_mode))
1252 return 0;
1253 rsyserr(FERROR_XFER, errno,
1254 "failed to write xattr %s for %s",
1255 XSTAT_ATTR, full_fname(fname));
1256 return -1;
1257 }
1258 }
1259
1260 return 0;
1261 }
1262
1263 int x_stat(const char *fname, STRUCT_STAT *fst, STRUCT_STAT *xst)
1264 {
1265 int ret = do_stat(fname, fst);
1266 if ((ret < 0 || get_stat_xattr(fname, -1, fst, xst) < 0) && xst)
1267 xst->st_mode = 0;
1268 return ret;
1269 }
1270
1271 int x_lstat(const char *fname, STRUCT_STAT *fst, STRUCT_STAT *xst)
1272 {
1273 int ret = do_lstat(fname, fst);
1274 if ((ret < 0 || get_stat_xattr(fname, -1, fst, xst) < 0) && xst)
1275 xst->st_mode = 0;
1276 return ret;
1277 }
1278
1279 int x_fstat(int fd, STRUCT_STAT *fst, STRUCT_STAT *xst)
1280 {
1281 int ret = do_fstat(fd, fst);
1282 if ((ret < 0 || get_stat_xattr(NULL, fd, fst, xst) < 0) && xst)
1283 xst->st_mode = 0;
1284 return ret;
1285 }
1286
1287 #endif /* SUPPORT_XATTRS */
rsync: a fast, versatile, remote (and local) file-copying tool