xattrs.c

   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) 2006-2022 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 extern struct name_num_item *xattr_sum_nni;
  43 extern int xattr_sum_len;
  44
  45 #define RSYNC_XAL_INITIAL 5
  46 #define RSYNC_XAL_LIST_INITIAL 100
  47
  48 #define MAX_XATTR_DIGEST_LEN MD5_DIGEST_LEN
  49 #define MAX_FULL_DATUM 32
  50
  51 #define HAS_PREFIX(str, prfx) (*(str) == *(prfx) && strncmp(str, prfx, sizeof (prfx) - 1) == 0)
  52
  53 #define XATTR_ABBREV(x) ((size_t)((x).name - (x).datum) < (x).datum_len)
  54
  55 #define XSTATE_ABBREV   1
  56 #define XSTATE_DONE     2
  57 #define XSTATE_TODO     3
  58
  59 #define USER_PREFIX "user."
  60 #define UPRE_LEN ((int)sizeof USER_PREFIX - 1)
  61 #define SYSTEM_PREFIX "system."
  62 #define SPRE_LEN ((int)sizeof SYSTEM_PREFIX - 1)
  63
  64 #ifdef HAVE_LINUX_XATTRS
  65 #define MIGHT_NEED_RPRE (am_root <= 0)
  66 #define RSYNC_PREFIX USER_PREFIX "rsync."
  67 #else
  68 #define MIGHT_NEED_RPRE am_root
  69 #define RSYNC_PREFIX "rsync."
  70 #endif
  71 #define RPRE_LEN ((int)sizeof RSYNC_PREFIX - 1)
  72
  73 #define XSTAT_SUFFIX "stat"
  74 #define XSTAT_ATTR RSYNC_PREFIX "%" XSTAT_SUFFIX
  75 #define XACC_ACL_SUFFIX "aacl"
  76 #define XACC_ACL_ATTR RSYNC_PREFIX "%" XACC_ACL_SUFFIX
  77 #define XDEF_ACL_SUFFIX "dacl"
  78 #define XDEF_ACL_ATTR RSYNC_PREFIX "%" XDEF_ACL_SUFFIX
  79
  80 typedef struct {
  81         char *datum, *name;
  82         size_t datum_len, name_len;
  83         int num;
  84 } rsync_xa;
  85
  86 struct _rsync_xa_list;
  87
  88 typedef struct _rsync_xa_list_ref {
  89         struct _rsync_xa_list_ref *next;
  90         int ndx;
  91 } rsync_xa_list_ref;
  92
  93 typedef struct _rsync_xa_list {
  94         int ndx;
  95         int64 key;
  96         item_list xa_items;
  97 } rsync_xa_list;
  98
  99 static size_t namebuf_len = 0;
 100 static char *namebuf = NULL;
 101
 102 static const rsync_xa_list empty_xa_list = {
 103         .xa_items = EMPTY_ITEM_LIST,
 104 };
 105 static const item_list empty_xattr = EMPTY_ITEM_LIST;
 106 static item_list rsync_xal_l = EMPTY_ITEM_LIST;
 107 static struct hashtable *rsync_xal_h = NULL;
 108
 109 static size_t prior_xattr_count = (size_t)-1;
 110
 111 /* ------------------------------------------------------------------------- */
 112
 113 static void rsync_xal_free(item_list *xalp)
 114 {
 115         size_t i;
 116         rsync_xa *rxas = xalp->items;
 117
 118         if (!xalp->malloced)
 119                 return;
 120
 121         for (i = 0; i < xalp->count; i++) {
 122                 free(rxas[i].datum);
 123                 /*free(rxas[i].name);*/
 124         }
 125         free(xalp->items);
 126 }
 127
 128 void free_xattr(stat_x *sxp)
 129 {
 130         if (!sxp->xattr)
 131                 return;
 132         rsync_xal_free(sxp->xattr);
 133         free(sxp->xattr);
 134         sxp->xattr = NULL;
 135 }
 136
 137 static int rsync_xal_compare_names(const void *x1, const void *x2)
 138 {
 139         const rsync_xa *xa1 = x1;
 140         const rsync_xa *xa2 = x2;
 141         return strcmp(xa1->name, xa2->name);
 142 }
 143
 144 static ssize_t get_xattr_names(const char *fname)
 145 {
 146         ssize_t list_len;
 147         int64 arg;
 148
 149         if (!namebuf) {
 150                 namebuf_len = 1024;
 151                 namebuf = new_array(char, namebuf_len);
 152         }
 153
 154         while (1) {
 155                 /* The length returned includes all the '\0' terminators. */
 156                 list_len = sys_llistxattr(fname, namebuf, namebuf_len);
 157                 if (list_len >= 0) {
 158                         if ((size_t)list_len <= namebuf_len)
 159                                 break;
 160                 } else if (errno == ENOTSUP)
 161                         return 0;
 162                 else if (errno != ERANGE) {
 163                         arg = namebuf_len;
 164                   got_error:
 165                         rsyserr(FERROR_XFER, errno,
 166                                 "get_xattr_names: llistxattr(%s,%s) failed",
 167                                 full_fname(fname), big_num(arg));
 168                         return -1;
 169                 }
 170                 list_len = sys_llistxattr(fname, NULL, 0);
 171                 if (list_len < 0) {
 172                         arg = 0;
 173                         goto got_error;
 174                 }
 175                 if (namebuf_len)
 176                         free(namebuf);
 177                 namebuf_len = list_len + 1024;
 178                 namebuf = new_array(char, namebuf_len);
 179         }
 180
 181         return list_len;
 182 }
 183
 184 /* On entry, the *len_ptr parameter contains the size of the extra space we
 185  * should allocate when we create a buffer for the data.  On exit, it contains
 186  * the length of the datum. */
 187 static char *get_xattr_data(const char *fname, const char *name, size_t *len_ptr, int no_missing_error)
 188 {
 189         size_t datum_len = sys_lgetxattr(fname, name, NULL, 0);
 190         size_t extra_len = *len_ptr;
 191         char *ptr;
 192
 193         *len_ptr = datum_len;
 194
 195         if (datum_len == (size_t)-1) {
 196                 if (errno == ENOTSUP || no_missing_error)
 197                         return NULL;
 198                 rsyserr(FERROR_XFER, errno,
 199                         "get_xattr_data: lgetxattr(%s,\"%s\",0) failed",
 200                         full_fname(fname), name);
 201                 return NULL;
 202         }
 203
 204         if (!datum_len && !extra_len)
 205                 extra_len = 1; /* request non-zero amount of memory */
 206         if (SIZE_MAX - datum_len < extra_len)
 207                 overflow_exit("get_xattr_data");
 208         ptr = new_array(char, datum_len + extra_len);
 209
 210         if (datum_len) {
 211                 size_t len = sys_lgetxattr(fname, name, ptr, datum_len);
 212                 if (len != datum_len) {
 213                         if (len == (size_t)-1) {
 214                                 rsyserr(FERROR_XFER, errno,
 215                                         "get_xattr_data: lgetxattr(%s,\"%s\",%ld) failed",
 216                                         full_fname(fname), name, (long)datum_len);
 217                         } else {
 218                                 rprintf(FERROR_XFER,
 219                                         "get_xattr_data: lgetxattr(%s,\"%s\",%ld) returned %ld\n",
 220                                         full_fname(fname), name,
 221                                         (long)datum_len, (long)len);
 222                         }
 223                         free(ptr);
 224                         return NULL;
 225                 }
 226         }
 227
 228         return ptr;
 229 }
 230
 231 static int rsync_xal_get(const char *fname, item_list *xalp)
 232 {
 233         ssize_t list_len, name_len;
 234         size_t datum_len, name_offset;
 235         char *name, *ptr;
 236 #ifdef HAVE_LINUX_XATTRS
 237         int user_only = am_sender ? 0 : !am_root;
 238 #endif
 239         rsync_xa *rxa;
 240         int count;
 241
 242         /* This puts the name list into the "namebuf" buffer. */
 243         if ((list_len = get_xattr_names(fname)) < 0)
 244                 return -1;
 245
 246         for (name = namebuf; list_len > 0; name += name_len) {
 247                 name_len = strlen(name) + 1;
 248                 list_len -= name_len;
 249
 250                 if (saw_xattr_filter) {
 251                         if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS))
 252                                 continue;
 253                 }
 254 #ifdef HAVE_LINUX_XATTRS
 255                 /* Choose between ignoring the system namespace or (non-root) ignoring any non-user namespace. */
 256                 else if (user_only ? !HAS_PREFIX(name, USER_PREFIX) : HAS_PREFIX(name, SYSTEM_PREFIX))
 257                         continue;
 258 #endif
 259
 260                 /* No rsync.%FOO attributes are copied w/o 2 -X options. */
 261                 if (name_len > RPRE_LEN && name[RPRE_LEN] == '%' && HAS_PREFIX(name, RSYNC_PREFIX)) {
 262                         if ((am_sender && preserve_xattrs < 2)
 263                          || (am_root < 0
 264                           && (strcmp(name+RPRE_LEN+1, XSTAT_SUFFIX) == 0
 265                            || strcmp(name+RPRE_LEN+1, XACC_ACL_SUFFIX) == 0
 266                            || strcmp(name+RPRE_LEN+1, XDEF_ACL_SUFFIX) == 0)))
 267                                 continue;
 268                 }
 269
 270                 datum_len = name_len; /* Pass extra size to get_xattr_data() */
 271                 if (!(ptr = get_xattr_data(fname, name, &datum_len, 0)))
 272                         return -1;
 273
 274                 if (datum_len > MAX_FULL_DATUM) {
 275                         /* For large datums, we store a flag and a checksum. */
 276                         name_offset = 1 + MAX_XATTR_DIGEST_LEN;
 277                         sum_init(xattr_sum_nni, checksum_seed);
 278                         sum_update(ptr, datum_len);
 279                         free(ptr);
 280
 281                         ptr = new_array(char, name_offset + name_len);
 282                         *ptr = XSTATE_ABBREV;
 283                         sum_end(ptr + 1);
 284                 } else
 285                         name_offset = datum_len;
 286
 287                 rxa = EXPAND_ITEM_LIST(xalp, rsync_xa, RSYNC_XAL_INITIAL);
 288                 rxa->name = ptr + name_offset;
 289                 memcpy(rxa->name, name, name_len);
 290                 rxa->datum = ptr;
 291                 rxa->name_len = name_len;
 292                 rxa->datum_len = datum_len;
 293         }
 294         count = xalp->count;
 295         rxa = xalp->items;
 296         if (count > 1)
 297                 qsort(rxa, count, sizeof (rsync_xa), rsync_xal_compare_names);
 298         for (rxa += count-1; count; count--, rxa--)
 299                 rxa->num = count;
 300         return 0;
 301 }
 302
 303 /* Read the xattr(s) for this filename. */
 304 int get_xattr(const char *fname, stat_x *sxp)
 305 {
 306         sxp->xattr = new(item_list);
 307         *sxp->xattr = empty_xattr;
 308
 309         if (S_ISREG(sxp->st.st_mode) || S_ISDIR(sxp->st.st_mode)) {
 310                 /* Everyone supports this. */
 311         } else if (S_ISLNK(sxp->st.st_mode)) {
 312 #ifndef NO_SYMLINK_XATTRS
 313                 if (!preserve_links)
 314 #endif
 315                         return 0;
 316         } else if (IS_SPECIAL(sxp->st.st_mode)) {
 317 #ifndef NO_SPECIAL_XATTRS
 318                 if (!preserve_specials)
 319 #endif
 320                         return 0;
 321         } else if (IS_DEVICE(sxp->st.st_mode)) {
 322 #ifndef NO_DEVICE_XATTRS
 323                 if (!preserve_devices)
 324 #endif
 325                         return 0;
 326         } else if (IS_MISSING_FILE(sxp->st))
 327                 return 0;
 328
 329         if (rsync_xal_get(fname, sxp->xattr) < 0) {
 330                 free_xattr(sxp);
 331                 return -1;
 332         }
 333         return 0;
 334 }
 335
 336 int copy_xattrs(const char *source, const char *dest)
 337 {
 338         ssize_t list_len, name_len;
 339         size_t datum_len;
 340         char *name, *ptr;
 341 #ifdef HAVE_LINUX_XATTRS
 342         int user_only = am_sender ? 0 : am_root <= 0;
 343 #endif
 344
 345         /* This puts the name list into the "namebuf" buffer. */
 346         if ((list_len = get_xattr_names(source)) < 0)
 347                 return -1;
 348
 349         for (name = namebuf; list_len > 0; name += name_len) {
 350                 name_len = strlen(name) + 1;
 351                 list_len -= name_len;
 352
 353                 if (saw_xattr_filter) {
 354                         if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS))
 355                                 continue;
 356                 }
 357 #ifdef HAVE_LINUX_XATTRS
 358                 /* Choose between ignoring the system namespace or (non-root) ignoring any non-user namespace. */
 359                 else if (user_only ? !HAS_PREFIX(name, USER_PREFIX) : HAS_PREFIX(name, SYSTEM_PREFIX))
 360                         continue;
 361 #endif
 362
 363                 datum_len = 0;
 364                 if (!(ptr = get_xattr_data(source, name, &datum_len, 0)))
 365                         return -1;
 366                 if (sys_lsetxattr(dest, name, ptr, datum_len) < 0) {
 367                         int save_errno = errno ? errno : EINVAL;
 368                         rsyserr(FERROR_XFER, errno,
 369                                 "copy_xattrs: lsetxattr(%s,\"%s\") failed",
 370                                 full_fname(dest), name);
 371                         errno = save_errno;
 372                         return -1;
 373                 }
 374                 free(ptr);
 375         }
 376
 377         return 0;
 378 }
 379
 380 static int64 xattr_lookup_hash(const item_list *xalp)
 381 {
 382         const rsync_xa *rxas = xalp->items;
 383         size_t i;
 384         int64 key = hashlittle2(&xalp->count, sizeof xalp->count);
 385
 386         for (i = 0; i < xalp->count; i++) {
 387                 key += hashlittle2(rxas[i].name, rxas[i].name_len);
 388                 if (rxas[i].datum_len > MAX_FULL_DATUM)
 389                         key += hashlittle2(rxas[i].datum, xattr_sum_len);
 390                 else
 391                         key += hashlittle2(rxas[i].datum, rxas[i].datum_len);
 392         }
 393
 394         return key;
 395 }
 396
 397 static int find_matching_xattr(const item_list *xalp)
 398 {
 399         const struct ht_int64_node *node;
 400         const rsync_xa_list_ref *ref;
 401         int64 key;
 402
 403         if (rsync_xal_h == NULL)
 404                 return -1;
 405
 406         key = xattr_lookup_hash(xalp);
 407
 408         node = hashtable_find(rsync_xal_h, key, NULL);
 409         if (node == NULL)
 410                 return -1;
 411
 412         if (node->data == NULL)
 413                 return -1;
 414
 415         for (ref = node->data; ref != NULL; ref = ref->next) {
 416                 const rsync_xa_list *ptr = rsync_xal_l.items;
 417                 const rsync_xa *rxas1;
 418                 const rsync_xa *rxas2 = xalp->items;
 419                 size_t j;
 420
 421                 ptr += ref->ndx;
 422                 rxas1 = ptr->xa_items.items;
 423
 424                 /* Wrong number of elements? */
 425                 if (ptr->xa_items.count != xalp->count)
 426                         continue;
 427                 /* any elements different? */
 428                 for (j = 0; j < xalp->count; j++) {
 429                         if (rxas1[j].name_len != rxas2[j].name_len
 430                          || rxas1[j].datum_len != rxas2[j].datum_len
 431                          || strcmp(rxas1[j].name, rxas2[j].name))
 432                                 break;
 433                         if (rxas1[j].datum_len > MAX_FULL_DATUM) {
 434                                 if (memcmp(rxas1[j].datum + 1,
 435                                            rxas2[j].datum + 1,
 436                                            xattr_sum_len) != 0)
 437                                         break;
 438                         } else {
 439                                 if (memcmp(rxas1[j].datum, rxas2[j].datum,
 440                                            rxas2[j].datum_len))
 441                                         break;
 442                         }
 443                 }
 444                 /* no differences found.  This is The One! */
 445                 if (j == xalp->count)
 446                         return ref->ndx;
 447         }
 448
 449         return -1;
 450 }
 451
 452 /* Store *xalp on the end of rsync_xal_l */
 453 static int rsync_xal_store(item_list *xalp)
 454 {
 455         struct ht_int64_node *node;
 456         int ndx = rsync_xal_l.count; /* pre-incremented count */
 457         rsync_xa_list *new_list = EXPAND_ITEM_LIST(&rsync_xal_l, rsync_xa_list, RSYNC_XAL_LIST_INITIAL);
 458         rsync_xa_list_ref *new_ref;
 459         /* Since the following call starts a new list, we know it will hold the
 460          * entire initial-count, not just enough space for one new item. */
 461         *new_list = empty_xa_list;
 462         (void)EXPAND_ITEM_LIST(&new_list->xa_items, rsync_xa, xalp->count);
 463         memcpy(new_list->xa_items.items, xalp->items, xalp->count * sizeof (rsync_xa));
 464         new_list->xa_items.count = xalp->count;
 465         xalp->count = 0;
 466
 467         new_list->ndx = ndx;
 468         new_list->key = xattr_lookup_hash(&new_list->xa_items);
 469
 470         if (rsync_xal_h == NULL)
 471                 rsync_xal_h = hashtable_create(512, HT_KEY64);
 472
 473         new_ref = new0(rsync_xa_list_ref);
 474         new_ref->ndx = ndx;
 475
 476         node = hashtable_find(rsync_xal_h, new_list->key, new_ref);
 477         if (node->data != (void*)new_ref) {
 478                 rsync_xa_list_ref *ref = node->data;
 479
 480                 while (ref != NULL) {
 481                         if (ref->next != NULL) {
 482                                 ref = ref->next;
 483                                 continue;
 484                         }
 485
 486                         ref->next = new_ref;
 487                         break;
 488                 }
 489         }
 490
 491         return ndx;
 492 }
 493
 494 /* Send the make_xattr()-generated xattr list for this flist entry. */
 495 int send_xattr(int f, stat_x *sxp)
 496 {
 497         int ndx = find_matching_xattr(sxp->xattr);
 498
 499         /* Send 0 (-1 + 1) to indicate that literal xattr data follows. */
 500         write_varint(f, ndx + 1);
 501
 502         if (ndx < 0) {
 503                 rsync_xa *rxa;
 504                 int count = sxp->xattr->count;
 505                 write_varint(f, count);
 506                 for (rxa = sxp->xattr->items; count--; rxa++) {
 507                         size_t name_len = rxa->name_len;
 508                         const char *name = rxa->name;
 509                         /* Strip the rsync prefix from disguised namespaces. */
 510                         if (name_len > RPRE_LEN
 511 #ifdef HAVE_LINUX_XATTRS
 512                          && am_root < 0
 513 #endif
 514                          && name[RPRE_LEN] != '%' && HAS_PREFIX(name, RSYNC_PREFIX)) {
 515                                 name += RPRE_LEN;
 516                                 name_len -= RPRE_LEN;
 517                         }
 518 #ifndef HAVE_LINUX_XATTRS
 519                         else {
 520                                 /* Put everything else in the user namespace. */
 521                                 name_len += UPRE_LEN;
 522                         }
 523 #endif
 524                         write_varint(f, name_len);
 525                         write_varint(f, rxa->datum_len);
 526 #ifndef HAVE_LINUX_XATTRS
 527                         if (name_len > rxa->name_len) {
 528                                 write_buf(f, USER_PREFIX, UPRE_LEN);
 529                                 name_len -= UPRE_LEN;
 530                         }
 531 #endif
 532                         write_buf(f, name, name_len);
 533                         if (rxa->datum_len > MAX_FULL_DATUM)
 534                                 write_buf(f, rxa->datum + 1, xattr_sum_len);
 535                         else
 536                                 write_bigbuf(f, rxa->datum, rxa->datum_len);
 537                 }
 538                 ndx = rsync_xal_store(sxp->xattr); /* adds item to rsync_xal_l */
 539         }
 540
 541         return ndx;
 542 }
 543
 544 /* Return a flag indicating if we need to change a file's xattrs.  If
 545  * "find_all" is specified, also mark any abbreviated xattrs that we
 546  * need so that send_xattr_request() can tell the sender about them. */
 547 int xattr_diff(struct file_struct *file, stat_x *sxp, int find_all)
 548 {
 549         const rsync_xa_list *glst = rsync_xal_l.items;
 550         const item_list *lst;
 551         rsync_xa *snd_rxa, *rec_rxa;
 552         int snd_cnt, rec_cnt;
 553         int cmp, same, xattrs_equal = 1;
 554
 555         if (sxp && XATTR_READY(*sxp)) {
 556                 rec_rxa = sxp->xattr->items;
 557                 rec_cnt = sxp->xattr->count;
 558         } else {
 559                 rec_rxa = NULL;
 560                 rec_cnt = 0;
 561         }
 562
 563         if (F_XATTR(file) >= 0) {
 564                 glst += F_XATTR(file);
 565                 lst = &glst->xa_items;
 566         } else
 567                 lst = &empty_xattr;
 568
 569         snd_rxa = lst->items;
 570         snd_cnt = lst->count;
 571
 572         /* If the count of the sender's xattrs is different from our
 573          * (receiver's) xattrs, the lists are not the same. */
 574         if (snd_cnt != rec_cnt) {
 575                 if (!find_all)
 576                         return 1;
 577                 xattrs_equal = 0;
 578         }
 579
 580         while (snd_cnt) {
 581                 cmp = rec_cnt ? strcmp(snd_rxa->name, rec_rxa->name) : -1;
 582                 if (cmp > 0)
 583                         same = 0;
 584                 else if (snd_rxa->datum_len > MAX_FULL_DATUM) {
 585                         same = cmp == 0 && snd_rxa->datum_len == rec_rxa->datum_len
 586                             && memcmp(snd_rxa->datum + 1, rec_rxa->datum + 1,
 587                                       xattr_sum_len) == 0;
 588                         /* Flag unrequested items that we need. */
 589                         if (!same && find_all && snd_rxa->datum[0] == XSTATE_ABBREV)
 590                                 snd_rxa->datum[0] = XSTATE_TODO;
 591                 } else {
 592                         same = cmp == 0 && snd_rxa->datum_len == rec_rxa->datum_len
 593                             && memcmp(snd_rxa->datum, rec_rxa->datum,
 594                                       snd_rxa->datum_len) == 0;
 595                 }
 596                 if (!same) {
 597                         if (!find_all)
 598                                 return 1;
 599                         xattrs_equal = 0;
 600                 }
 601
 602                 if (cmp <= 0) {
 603                         snd_rxa++;
 604                         snd_cnt--;
 605                 }
 606                 if (cmp >= 0) {
 607                         rec_rxa++;
 608                         rec_cnt--;
 609                 }
 610         }
 611
 612         if (rec_cnt)
 613                 xattrs_equal = 0;
 614
 615         return !xattrs_equal;
 616 }
 617
 618 /* When called by the generator (with a NULL fname), this tells the sender
 619  * all the abbreviated xattr values we need.  When called by the sender
 620  * (with a non-NULL fname), we send all the extra xattr data it needs.
 621  * The generator may also call with f_out < 0 to just change all the
 622  * XSTATE_ABBREV states into XSTATE_DONE. */
 623 void send_xattr_request(const char *fname, struct file_struct *file, int f_out)
 624 {
 625         const rsync_xa_list *glst = rsync_xal_l.items;
 626         const item_list *lst;
 627         int cnt, prior_req = 0;
 628         rsync_xa *rxa;
 629
 630         glst += F_XATTR(file);
 631         lst = &glst->xa_items;
 632
 633         for (rxa = lst->items, cnt = lst->count; cnt--; rxa++) {
 634                 if (rxa->datum_len <= MAX_FULL_DATUM)
 635                         continue;
 636                 switch (rxa->datum[0]) {
 637                 case XSTATE_ABBREV:
 638                         /* Items left abbreviated matched the sender's checksum, so
 639                          * the receiver will cache the local data for future use. */
 640                         if (am_generator)
 641                                 rxa->datum[0] = XSTATE_DONE;
 642                         continue;
 643                 case XSTATE_TODO:
 644                         assert(f_out >= 0);
 645                         break;
 646                 default:
 647                         continue;
 648                 }
 649
 650                 /* Flag that we handled this abbreviated item. */
 651                 rxa->datum[0] = XSTATE_DONE;
 652
 653                 write_varint(f_out, rxa->num - prior_req);
 654                 prior_req = rxa->num;
 655
 656                 if (fname) {
 657                         size_t len = 0;
 658                         char *ptr;
 659
 660                         /* Re-read the long datum. */
 661                         if (!(ptr = get_xattr_data(fname, rxa->name, &len, 0))) {
 662                                 rprintf(FERROR_XFER, "failed to re-read xattr %s for %s\n", rxa->name, fname);
 663                                 write_varint(f_out, 0);
 664                                 continue;
 665                         }
 666
 667                         write_varint(f_out, len); /* length might have changed! */
 668                         write_bigbuf(f_out, ptr, len);
 669                         free(ptr);
 670                 }
 671         }
 672
 673         if (f_out >= 0)
 674                 write_byte(f_out, 0); /* end the list */
 675 }
 676
 677 /* When called by the sender, read the request from the generator and mark
 678  * any needed xattrs with a flag that lets us know they need to be sent to
 679  * the receiver.  When called by the receiver, reads the sent data and
 680  * stores it in place of its checksum. */
 681 int recv_xattr_request(struct file_struct *file, int f_in)
 682 {
 683         const rsync_xa_list *glst = rsync_xal_l.items;
 684         const item_list *lst;
 685         char *old_datum, *name;
 686         rsync_xa *rxa;
 687         int rel_pos, cnt, num, got_xattr_data = 0;
 688
 689         if (F_XATTR(file) < 0) {
 690                 rprintf(FERROR, "recv_xattr_request: internal data error!\n");
 691                 exit_cleanup(RERR_PROTOCOL);
 692         }
 693         glst += F_XATTR(file);
 694         lst = &glst->xa_items;
 695
 696         cnt = lst->count;
 697         rxa = lst->items;
 698         num = 0;
 699         while ((rel_pos = read_varint(f_in)) != 0) {
 700                 num += rel_pos;
 701                 if (am_sender) {
 702                         /* The sender-related num values are only in order on the sender.
 703                          * We use that order here to scan forward or backward as needed. */
 704                         if (rel_pos < 0) {
 705                                 while (cnt < (int)lst->count && rxa->num > num) {
 706                                         rxa--;
 707                                         cnt++;
 708                                 }
 709                         } else {
 710                                 while (cnt > 1 && rxa->num < num) {
 711                                         rxa++;
 712                                         cnt--;
 713                                 }
 714                         }
 715                 } else {
 716                         int j;
 717                         /* The receiving side has no known num order, so we just scan
 718                          * forward (w/wrap) and hope that the next value is near by. */
 719                         for (j = lst->count; j > 1 && rxa->num != num; j--) {
 720                                 if (--cnt)
 721                                         rxa++;
 722                                 else {
 723                                         cnt = lst->count;
 724                                         rxa = lst->items;
 725                                 }
 726                         }
 727                 }
 728                 if (!cnt || rxa->num != num) {
 729                         rprintf(FERROR, "[%s] could not find xattr #%d for %s\n",
 730                                 who_am_i(), num, f_name(file, NULL));
 731                         exit_cleanup(RERR_PROTOCOL);
 732                 }
 733                 if (!XATTR_ABBREV(*rxa) || rxa->datum[0] != XSTATE_ABBREV) {
 734                         rprintf(FERROR, "[%s] internal abbrev error on %s (%s, len=%ld)!\n",
 735                                 who_am_i(), f_name(file, NULL), rxa->name, (long)rxa->datum_len);
 736                         exit_cleanup(RERR_PROTOCOL);
 737                 }
 738
 739                 if (am_sender) {
 740                         rxa->datum[0] = XSTATE_TODO;
 741                         continue;
 742                 }
 743
 744                 old_datum = rxa->datum;
 745                 rxa->datum_len = read_varint(f_in);
 746
 747                 if (SIZE_MAX - rxa->name_len < rxa->datum_len)
 748                         overflow_exit("recv_xattr_request");
 749                 rxa->datum = new_array(char, rxa->datum_len + rxa->name_len);
 750                 name = rxa->datum + rxa->datum_len;
 751                 memcpy(name, rxa->name, rxa->name_len);
 752                 rxa->name = name;
 753                 free(old_datum);
 754                 read_buf(f_in, rxa->datum, rxa->datum_len);
 755                 got_xattr_data = 1;
 756         }
 757
 758         return got_xattr_data;
 759 }
 760
 761 /* ------------------------------------------------------------------------- */
 762
 763 /* receive and build the rsync_xattr_lists */
 764 void receive_xattr(int f, struct file_struct *file)
 765 {
 766         static item_list temp_xattr = EMPTY_ITEM_LIST;
 767         int count, num;
 768 #ifdef HAVE_LINUX_XATTRS
 769         int need_sort = 0;
 770 #else
 771         int need_sort = 1;
 772 #endif
 773         int ndx = read_varint(f);
 774
 775         if (ndx < 0 || (size_t)ndx > rsync_xal_l.count) {
 776                 rprintf(FERROR, "receive_xattr: xa index %d out of"
 777                         " range for %s\n", ndx, f_name(file, NULL));
 778                 exit_cleanup(RERR_STREAMIO);
 779         }
 780
 781         if (ndx != 0) {
 782                 F_XATTR(file) = ndx - 1;
 783                 return;
 784         }
 785
 786         if ((count = read_varint(f)) != 0) {
 787                 (void)EXPAND_ITEM_LIST(&temp_xattr, rsync_xa, count);
 788                 temp_xattr.count = 0;
 789         }
 790
 791         for (num = 1; num <= count; num++) {
 792                 char *ptr, *name;
 793                 rsync_xa *rxa;
 794                 size_t name_len = read_varint(f);
 795                 size_t datum_len = read_varint(f);
 796                 size_t dget_len = datum_len > MAX_FULL_DATUM ? 1 + (size_t)xattr_sum_len : datum_len;
 797                 size_t extra_len = MIGHT_NEED_RPRE ? RPRE_LEN : 0;
 798                 if (SIZE_MAX - dget_len < extra_len || SIZE_MAX - dget_len - extra_len < name_len)
 799                         overflow_exit("receive_xattr");
 800                 ptr = new_array(char, dget_len + extra_len + name_len);
 801                 name = ptr + dget_len + extra_len;
 802                 read_buf(f, name, name_len);
 803                 if (name_len < 1 || name[name_len-1] != '\0') {
 804                         rprintf(FERROR, "Invalid xattr name received (missing trailing \\0).\n");
 805                         exit_cleanup(RERR_FILEIO);
 806                 }
 807                 if (dget_len == datum_len)
 808                         read_buf(f, ptr, dget_len);
 809                 else {
 810                         *ptr = XSTATE_ABBREV;
 811                         read_buf(f, ptr + 1, xattr_sum_len);
 812                 }
 813
 814                 if (saw_xattr_filter) {
 815                         if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS)) {
 816                                 free(ptr);
 817                                 continue;
 818                         }
 819                 }
 820 #ifdef HAVE_LINUX_XATTRS
 821                 /* Non-root can only save the user namespace. */
 822                 if (am_root <= 0 && !HAS_PREFIX(name, USER_PREFIX)) {
 823                         if (!am_root && !saw_xattr_filter) {
 824                                 free(ptr);
 825                                 continue;
 826                         }
 827                         name -= RPRE_LEN;
 828                         name_len += RPRE_LEN;
 829                         memcpy(name, RSYNC_PREFIX, RPRE_LEN);
 830                         need_sort = 1;
 831                 }
 832 #else
 833                 /* This OS only has a user namespace, so we either
 834                  * strip the user prefix, or we put a non-user
 835                  * namespace inside our rsync hierarchy. */
 836                 if (HAS_PREFIX(name, USER_PREFIX)) {
 837                         name += UPRE_LEN;
 838                         name_len -= UPRE_LEN;
 839                 } else if (am_root) {
 840                         name -= RPRE_LEN;
 841                         name_len += RPRE_LEN;
 842                         memcpy(name, RSYNC_PREFIX, RPRE_LEN);
 843                 } else {
 844                         free(ptr);
 845                         continue;
 846                 }
 847 #endif
 848                 /* No rsync.%FOO attributes are copied w/o 2 -X options. */
 849                 if (preserve_xattrs < 2 && name_len > RPRE_LEN
 850                  && name[RPRE_LEN] == '%' && HAS_PREFIX(name, RSYNC_PREFIX)) {
 851                         free(ptr);
 852                         continue;
 853                 }
 854
 855                 rxa = EXPAND_ITEM_LIST(&temp_xattr, rsync_xa, 1);
 856                 rxa->name = name;
 857                 rxa->datum = ptr;
 858                 rxa->name_len = name_len;
 859                 rxa->datum_len = datum_len;
 860                 rxa->num = num;
 861         }
 862
 863         if (need_sort && count > 1)
 864                 qsort(temp_xattr.items, count, sizeof (rsync_xa), rsync_xal_compare_names);
 865
 866         ndx = rsync_xal_store(&temp_xattr); /* adds item to rsync_xal_l */
 867
 868         F_XATTR(file) = ndx;
 869 }
 870
 871 /* Turn the xattr data in stat_x into cached xattr data, setting the index
 872  * values in the file struct. */
 873 void cache_tmp_xattr(struct file_struct *file, stat_x *sxp)
 874 {
 875         int ndx;
 876
 877         if (!sxp->xattr)
 878                 return;
 879
 880         if (prior_xattr_count == (size_t)-1)
 881                 prior_xattr_count = rsync_xal_l.count;
 882         ndx = find_matching_xattr(sxp->xattr);
 883         if (ndx < 0)
 884                 rsync_xal_store(sxp->xattr); /* adds item to rsync_xal_l */
 885
 886         F_XATTR(file) = ndx;
 887 }
 888
 889 void uncache_tmp_xattrs(void)
 890 {
 891         if (prior_xattr_count != (size_t)-1) {
 892                 rsync_xa_list *xa_list_item = rsync_xal_l.items;
 893                 rsync_xa_list *xa_list_start = xa_list_item + prior_xattr_count;
 894                 xa_list_item += rsync_xal_l.count;
 895                 rsync_xal_l.count = prior_xattr_count;
 896                 while (xa_list_item-- > xa_list_start) {
 897                         struct ht_int64_node *node;
 898                         rsync_xa_list_ref *ref;
 899
 900                         rsync_xal_free(&xa_list_item->xa_items);
 901
 902                         if (rsync_xal_h == NULL)
 903                                 continue;
 904
 905                         node = hashtable_find(rsync_xal_h, xa_list_item->key, NULL);
 906                         if (node == NULL)
 907                                 continue;
 908
 909                         if (node->data == NULL)
 910                                 continue;
 911
 912                         ref = node->data;
 913                         if (xa_list_item->ndx == ref->ndx) {
 914                                 /* xa_list_item is the first in the list. */
 915                                 node->data = ref->next;
 916                                 free(ref);
 917                                 continue;
 918                         }
 919
 920                         while (1) {
 921                                 rsync_xa_list_ref *next = ref->next;
 922                                 if (next == NULL)
 923                                         break;
 924                                 if (xa_list_item->ndx == next->ndx) {
 925                                         ref->next = next->next;
 926                                         free(next);
 927                                         break;
 928                                 }
 929                                 ref = next;
 930                         }
 931                 }
 932                 prior_xattr_count = (size_t)-1;
 933         }
 934 }
 935
 936 static int rsync_xal_set(const char *fname, item_list *xalp,
 937                          const char *fnamecmp, stat_x *sxp)
 938 {
 939         rsync_xa *rxas = xalp->items;
 940         ssize_t list_len;
 941         size_t i, len;
 942         char *name, *ptr, sum[MAX_XATTR_DIGEST_LEN];
 943 #ifdef HAVE_LINUX_XATTRS
 944         int user_only = am_root <= 0;
 945 #endif
 946         size_t name_len;
 947         int ret = 0;
 948
 949         /* This puts the current name list into the "namebuf" buffer. */
 950         if ((list_len = get_xattr_names(fname)) < 0)
 951                 return -1;
 952
 953         for (i = 0; i < xalp->count; i++) {
 954                 name = rxas[i].name;
 955
 956                 if (XATTR_ABBREV(rxas[i])) {
 957                         /* See if the fnamecmp version is identical. */
 958                         len = name_len = rxas[i].name_len;
 959                         if ((ptr = get_xattr_data(fnamecmp, name, &len, 1)) == NULL) {
 960                           still_abbrev:
 961                                 if (am_generator)
 962                                         continue;
 963                                 rprintf(FERROR, "Missing abbreviated xattr value, %s, for %s\n",
 964                                         rxas[i].name, full_fname(fname));
 965                                 ret = -1;
 966                                 continue;
 967                         }
 968                         if (len != rxas[i].datum_len) {
 969                                 free(ptr);
 970                                 goto still_abbrev;
 971                         }
 972
 973                         sum_init(xattr_sum_nni, checksum_seed);
 974                         sum_update(ptr, len);
 975                         sum_end(sum);
 976                         if (memcmp(sum, rxas[i].datum + 1, xattr_sum_len) != 0) {
 977                                 free(ptr);
 978                                 goto still_abbrev;
 979                         }
 980
 981                         if (fname == fnamecmp)
 982                                 ; /* Value is already set when identical */
 983                         else if (sys_lsetxattr(fname, name, ptr, len) < 0) {
 984                                 rsyserr(FERROR_XFER, errno,
 985                                         "rsync_xal_set: lsetxattr(%s,\"%s\") failed",
 986                                         full_fname(fname), name);
 987                                 ret = -1;
 988                         } else /* make sure caller sets mtime */
 989                                 sxp->st.st_mtime = (time_t)-1;
 990
 991                         if (am_generator) { /* generator items stay abbreviated */
 992                                 free(ptr);
 993                                 continue;
 994                         }
 995
 996                         memcpy(ptr + len, name, name_len);
 997                         free(rxas[i].datum);
 998
 999                         rxas[i].name = name = ptr + len;
1000                         rxas[i].datum = ptr;
1001                         continue;
1002                 }
1003
1004                 if (sys_lsetxattr(fname, name, rxas[i].datum, rxas[i].datum_len) < 0) {
1005                         rsyserr(FERROR_XFER, errno,
1006                                 "rsync_xal_set: lsetxattr(%s,\"%s\") failed",
1007                                 full_fname(fname), name);
1008                         ret = -1;
1009                 } else /* make sure caller sets mtime */
1010                         sxp->st.st_mtime = (time_t)-1;
1011         }
1012
1013         /* Remove any extraneous names. */
1014         for (name = namebuf; list_len > 0; name += name_len) {
1015                 name_len = strlen(name) + 1;
1016                 list_len -= name_len;
1017
1018                 if (saw_xattr_filter) {
1019                         if (name_is_excluded(name, NAME_IS_XATTR, ALL_FILTERS))
1020                                 continue;
1021                 }
1022 #ifdef HAVE_LINUX_XATTRS
1023                 /* Choose between ignoring the system namespace or (non-root) ignoring any non-user namespace. */
1024                 else if (user_only ? !HAS_PREFIX(name, USER_PREFIX) : HAS_PREFIX(name, SYSTEM_PREFIX))
1025                         continue;
1026 #endif
1027                 if (am_root < 0 && name_len > RPRE_LEN && name[RPRE_LEN] == '%' && strcmp(name, XSTAT_ATTR) == 0)
1028                         continue;
1029
1030                 for (i = 0; i < xalp->count; i++) {
1031                         if (strcmp(name, rxas[i].name) == 0)
1032                                 break;
1033                 }
1034                 if (i == xalp->count) {
1035                         if (sys_lremovexattr(fname, name) < 0) {
1036                                 rsyserr(FERROR_XFER, errno,
1037                                         "rsync_xal_set: lremovexattr(%s,\"%s\") failed",
1038                                         full_fname(fname), name);
1039                                 ret = -1;
1040                         } else /* make sure caller sets mtime */
1041                                 sxp->st.st_mtime = (time_t)-1;
1042                 }
1043         }
1044
1045         return ret;
1046 }
1047
1048 /* Set extended attributes on indicated filename. */
1049 int set_xattr(const char *fname, const struct file_struct *file, const char *fnamecmp, stat_x *sxp)
1050 {
1051         rsync_xa_list *glst = rsync_xal_l.items;
1052         item_list *lst;
1053         int ndx, added_write_perm = 0;
1054
1055         if (dry_run)
1056                 return 1; /* FIXME: --dry-run needs to compute this value */
1057
1058         if (read_only || list_only) {
1059                 errno = EROFS;
1060                 return -1;
1061         }
1062
1063 #ifdef NO_SPECIAL_XATTRS
1064         if (IS_SPECIAL(sxp->st.st_mode)) {
1065                 errno = ENOTSUP;
1066                 return -1;
1067         }
1068 #endif
1069 #ifdef NO_DEVICE_XATTRS
1070         if (IS_DEVICE(sxp->st.st_mode)) {
1071                 errno = ENOTSUP;
1072                 return -1;
1073         }
1074 #endif
1075 #ifdef NO_SYMLINK_XATTRS
1076         if (S_ISLNK(sxp->st.st_mode)) {
1077                 errno = ENOTSUP;
1078                 return -1;
1079         }
1080 #endif
1081
1082         /* If the target file lacks write permission, we try to add it
1083          * temporarily so we can change the extended attributes. */
1084         if (!am_root
1085 #ifdef SUPPORT_LINKS
1086          && !S_ISLNK(sxp->st.st_mode)
1087 #endif
1088          && access(fname, W_OK) < 0
1089          && do_chmod(fname, (sxp->st.st_mode & CHMOD_BITS) | S_IWUSR) == 0)
1090                 added_write_perm = 1;
1091
1092         ndx = F_XATTR(file);
1093         glst += ndx;
1094         lst = &glst->xa_items;
1095         int return_value = rsync_xal_set(fname, lst, fnamecmp, sxp);
1096         if (added_write_perm) /* remove the temporary write permission */
1097                 do_chmod(fname, sxp->st.st_mode);
1098         return return_value;
1099 }
1100
1101 #ifdef SUPPORT_ACLS
1102 char *get_xattr_acl(const char *fname, int is_access_acl, size_t *len_p)
1103 {
1104         const char *name = is_access_acl ? XACC_ACL_ATTR : XDEF_ACL_ATTR;
1105         *len_p = 0; /* no extra data alloc needed from get_xattr_data() */
1106         return get_xattr_data(fname, name, len_p, 1);
1107 }
1108
1109 int set_xattr_acl(const char *fname, int is_access_acl, const char *buf, size_t buf_len)
1110 {
1111         const char *name = is_access_acl ? XACC_ACL_ATTR : XDEF_ACL_ATTR;
1112         if (sys_lsetxattr(fname, name, buf, buf_len) < 0) {
1113                 rsyserr(FERROR_XFER, errno,
1114                         "set_xattr_acl: lsetxattr(%s,\"%s\") failed",
1115                         full_fname(fname), name);
1116                 return -1;
1117         }
1118         return 0;
1119 }
1120
1121 int del_def_xattr_acl(const char *fname)
1122 {
1123         return sys_lremovexattr(fname, XDEF_ACL_ATTR);
1124 }
1125 #endif
1126
1127 int get_stat_xattr(const char *fname, int fd, STRUCT_STAT *fst, STRUCT_STAT *xst)
1128 {
1129         unsigned int mode;
1130         int rdev_major, rdev_minor, uid, gid, len;
1131         char buf[256];
1132
1133         if (am_root >= 0 || IS_DEVICE(fst->st_mode) || IS_SPECIAL(fst->st_mode))
1134                 return -1;
1135
1136         if (xst)
1137                 *xst = *fst;
1138         else
1139                 xst = fst;
1140         if (fname) {
1141                 fd = -1;
1142                 len = sys_lgetxattr(fname, XSTAT_ATTR, buf, sizeof buf - 1);
1143         } else {
1144                 fname = "fd";
1145                 len = sys_fgetxattr(fd, XSTAT_ATTR, buf, sizeof buf - 1);
1146         }
1147         if (len >= (int)sizeof buf) {
1148                 len = -1;
1149                 errno = ERANGE;
1150         }
1151         if (len < 0) {
1152                 if (errno == ENOTSUP || errno == ENOATTR)
1153                         return -1;
1154                 if (errno == EPERM && S_ISLNK(fst->st_mode)) {
1155                         xst->st_uid = 0;
1156                         xst->st_gid = 0;
1157                         return 0;
1158                 }
1159                 rsyserr(FERROR_XFER, errno, "failed to read xattr %s for %s",
1160                         XSTAT_ATTR, full_fname(fname));
1161                 return -1;
1162         }
1163         buf[len] = '\0';
1164
1165         if (sscanf(buf, "%o %d,%d %d:%d",
1166                    &mode, &rdev_major, &rdev_minor, &uid, &gid) != 5) {
1167                 rprintf(FERROR, "Corrupt %s xattr attached to %s: \"%s\"\n",
1168                         XSTAT_ATTR, full_fname(fname), buf);
1169                 exit_cleanup(RERR_FILEIO);
1170         }
1171
1172         xst->st_mode = from_wire_mode(mode);
1173         xst->st_rdev = MAKEDEV(rdev_major, rdev_minor);
1174         xst->st_uid = uid;
1175         xst->st_gid = gid;
1176
1177         return 0;
1178 }
1179
1180 int set_stat_xattr(const char *fname, struct file_struct *file, mode_t new_mode)
1181 {
1182         STRUCT_STAT fst, xst;
1183         dev_t rdev;
1184         mode_t mode, fmode;
1185
1186         if (dry_run)
1187                 return 0;
1188
1189         if (read_only || list_only) {
1190                 rsyserr(FERROR_XFER, EROFS, "failed to write xattr %s for %s",
1191                         XSTAT_ATTR, full_fname(fname));
1192                 return -1;
1193         }
1194
1195         if (x_lstat(fname, &fst, &xst) < 0) {
1196                 rsyserr(FERROR_XFER, errno, "failed to re-stat %s",
1197                         full_fname(fname));
1198                 return -1;
1199         }
1200
1201         fst.st_mode &= (_S_IFMT | CHMOD_BITS);
1202         fmode = new_mode & (_S_IFMT | CHMOD_BITS);
1203
1204         if (IS_DEVICE(fmode)) {
1205                 uint32 *devp = F_RDEV_P(file);
1206                 rdev = MAKEDEV(DEV_MAJOR(devp), DEV_MINOR(devp));
1207         } else
1208                 rdev = 0;
1209
1210         /* Dump the special permissions and enable full owner access. */
1211         mode = (fst.st_mode & _S_IFMT) | (fmode & ACCESSPERMS)
1212              | (S_ISDIR(fst.st_mode) ? 0700 : 0600);
1213         if (fst.st_mode != mode)
1214                 do_chmod(fname, mode);
1215         if (!IS_DEVICE(fst.st_mode))
1216                 fst.st_rdev = 0; /* just in case */
1217
1218         if (mode == fmode && fst.st_rdev == rdev
1219          && fst.st_uid == F_OWNER(file) && fst.st_gid == F_GROUP(file)) {
1220                 /* xst.st_mode will be 0 if there's no current stat xattr */
1221                 if (xst.st_mode && sys_lremovexattr(fname, XSTAT_ATTR) < 0) {
1222                         rsyserr(FERROR_XFER, errno,
1223                                 "delete of stat xattr failed for %s",
1224                                 full_fname(fname));
1225                         return -1;
1226                 }
1227                 return 0;
1228         }
1229
1230         if (xst.st_mode != fmode || xst.st_rdev != rdev
1231          || xst.st_uid != F_OWNER(file) || xst.st_gid != F_GROUP(file)) {
1232                 char buf[256];
1233                 int len = snprintf(buf, sizeof buf, "%o %u,%u %u:%u",
1234                         to_wire_mode(fmode),
1235                         (int)major(rdev), (int)minor(rdev),
1236                         F_OWNER(file), F_GROUP(file));
1237                 if (sys_lsetxattr(fname, XSTAT_ATTR, buf, len) < 0) {
1238                         if (errno == EPERM && S_ISLNK(fst.st_mode))
1239                                 return 0;
1240                         rsyserr(FERROR_XFER, errno,
1241                                 "failed to write xattr %s for %s",
1242                                 XSTAT_ATTR, full_fname(fname));
1243                         return -1;
1244                 }
1245         }
1246
1247         return 0;
1248 }
1249
1250 int x_stat(const char *fname, STRUCT_STAT *fst, STRUCT_STAT *xst)
1251 {
1252         int ret = do_stat(fname, fst);
1253         if ((ret < 0 || get_stat_xattr(fname, -1, fst, xst) < 0) && xst)
1254                 xst->st_mode = 0;
1255         return ret;
1256 }
1257
1258 int x_lstat(const char *fname, STRUCT_STAT *fst, STRUCT_STAT *xst)
1259 {
1260         int ret = do_lstat(fname, fst);
1261         if ((ret < 0 || get_stat_xattr(fname, -1, fst, xst) < 0) && xst)
1262                 xst->st_mode = 0;
1263         return ret;
1264 }
1265
1266 int x_fstat(int fd, STRUCT_STAT *fst, STRUCT_STAT *xst)
1267 {
1268         int ret = do_fstat(fd, fst);
1269         if ((ret < 0 || get_stat_xattr(NULL, fd, fst, xst) < 0) && xst)
1270                 xst->st_mode = 0;
1271         return ret;
1272 }
1273
1274 #endif /* SUPPORT_XATTRS */