source3/modules/vfs_streams_xattr.c

   1 /*
   2  * Store streams in xattrs
   3  *
   4  * Copyright (C) Volker Lendecke, 2008
   5  *
   6  * Partly based on James Peach's Darwin module, which is
   7  *
   8  * Copyright (C) James Peach 2006-2007
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 3 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  22  */
  23
  24 #include "includes.h"
  25
  26 #undef DBGC_CLASS
  27 #define DBGC_CLASS DBGC_VFS
  28
  29 struct stream_io {
  30         char *base;
  31         char *xattr_name;
  32 };
  33
  34 static SMB_INO_T stream_inode(const SMB_STRUCT_STAT *sbuf, const char *sname)
  35 {
  36         struct MD5Context ctx;
  37         unsigned char hash[16];
  38         SMB_INO_T result;
  39         char *upper_sname;
  40
  41         DEBUG(10, ("stream_inode called for %lu/%lu [%s]\n",
  42                    (unsigned long)sbuf->st_dev,
  43                    (unsigned long)sbuf->st_ino, sname));
  44
  45         upper_sname = talloc_strdup_upper(talloc_tos(), sname);
  46         SMB_ASSERT(upper_sname != NULL);
  47
  48         MD5Init(&ctx);
  49         MD5Update(&ctx, (unsigned char *)&(sbuf->st_dev),
  50                   sizeof(sbuf->st_dev));
  51         MD5Update(&ctx, (unsigned char *)&(sbuf->st_ino),
  52                   sizeof(sbuf->st_ino));
  53         MD5Update(&ctx, (unsigned char *)upper_sname,
  54                   talloc_get_size(upper_sname)-1);
  55         MD5Final(hash, &ctx);
  56
  57         TALLOC_FREE(upper_sname);
  58
  59         /* Hopefully all the variation is in the lower 4 (or 8) bytes! */
  60         memcpy(&result, hash, sizeof(result));
  61
  62         DEBUG(10, ("stream_inode returns %lu\n", (unsigned long)result));
  63
  64         return result;
  65 }
  66
  67 static ssize_t get_xattr_size(connection_struct *conn,
  68                                 files_struct *fsp,
  69                                 const char *fname,
  70                                 const char *xattr_name)
  71 {
  72         NTSTATUS status;
  73         struct ea_struct ea;
  74         ssize_t result;
  75
  76         status = get_ea_value(talloc_tos(), conn, fsp, fname,
  77                               xattr_name, &ea);
  78
  79         if (!NT_STATUS_IS_OK(status)) {
  80                 return -1;
  81         }
  82
  83         result = ea.value.length-1;
  84         TALLOC_FREE(ea.value.data);
  85         return result;
  86 }
  87
  88
  89 static int streams_xattr_fstat(vfs_handle_struct *handle, files_struct *fsp,
  90                                SMB_STRUCT_STAT *sbuf)
  91 {
  92         struct stream_io *io = (struct stream_io *)
  93                 VFS_FETCH_FSP_EXTENSION(handle, fsp);
  94
  95         DEBUG(10, ("streams_xattr_fstat called for %d\n", fsp->fh->fd));
  96
  97         if (io == NULL || fsp->base_fsp == NULL) {
  98                 return SMB_VFS_NEXT_FSTAT(handle, fsp, sbuf);
  99         }
 100
 101         if (SMB_VFS_NEXT_FSTAT(handle, fsp, sbuf) == -1) {
 102                 return -1;
 103         }
 104
 105         sbuf->st_size = get_xattr_size(handle->conn, fsp->base_fsp,
 106                                         io->base, io->xattr_name);
 107         if (sbuf->st_size == -1) {
 108                 return -1;
 109         }
 110
 111         DEBUG(10, ("sbuf->st_size = %d\n", (int)sbuf->st_size));
 112
 113         sbuf->st_ino = stream_inode(sbuf, io->xattr_name);
 114         sbuf->st_mode &= ~S_IFMT;
 115         sbuf->st_mode |= S_IFREG;
 116         sbuf->st_blocks = sbuf->st_size % STAT_ST_BLOCKSIZE + 1;
 117
 118         return 0;
 119 }
 120
 121 static int streams_xattr_stat(vfs_handle_struct *handle, const char *fname,
 122                               SMB_STRUCT_STAT *sbuf)
 123 {
 124         NTSTATUS status;
 125         char *base = NULL, *sname = NULL;
 126         int result = -1;
 127         char *xattr_name;
 128
 129         if (!is_ntfs_stream_name(fname)) {
 130                 return SMB_VFS_NEXT_STAT(handle, fname, sbuf);
 131         }
 132
 133         status = split_ntfs_stream_name(talloc_tos(), fname, &base, &sname);
 134         if (!NT_STATUS_IS_OK(status)) {
 135                 errno = EINVAL;
 136                 return -1;
 137         }
 138
 139         if (sname == NULL){
 140                 return SMB_VFS_NEXT_STAT(handle, base, sbuf);
 141         }
 142
 143         if (SMB_VFS_STAT(handle->conn, base, sbuf) == -1) {
 144                 goto fail;
 145         }
 146
 147         xattr_name = talloc_asprintf(talloc_tos(), "%s%s",
 148                                      SAMBA_XATTR_DOSSTREAM_PREFIX, sname);
 149         if (xattr_name == NULL) {
 150                 errno = ENOMEM;
 151                 goto fail;
 152         }
 153
 154         sbuf->st_size = get_xattr_size(handle->conn, NULL, base, xattr_name);
 155         if (sbuf->st_size == -1) {
 156                 errno = ENOENT;
 157                 goto fail;
 158         }
 159
 160         sbuf->st_ino = stream_inode(sbuf, xattr_name);
 161         sbuf->st_mode &= ~S_IFMT;
 162         sbuf->st_mode |= S_IFREG;
 163         sbuf->st_blocks = sbuf->st_size % STAT_ST_BLOCKSIZE + 1;
 164
 165         result = 0;
 166  fail:
 167         TALLOC_FREE(base);
 168         TALLOC_FREE(sname);
 169         return result;
 170 }
 171
 172 static int streams_xattr_lstat(vfs_handle_struct *handle, const char *fname,
 173                                SMB_STRUCT_STAT *sbuf)
 174 {
 175         NTSTATUS status;
 176         char *base, *sname;
 177         int result = -1;
 178         char *xattr_name;
 179
 180         if (!is_ntfs_stream_name(fname)) {
 181                 return SMB_VFS_NEXT_LSTAT(handle, fname, sbuf);
 182         }
 183
 184         status = split_ntfs_stream_name(talloc_tos(), fname, &base, &sname);
 185         if (!NT_STATUS_IS_OK(status)) {
 186                 errno = EINVAL;
 187                 goto fail;
 188         }
 189
 190         if (sname == NULL){
 191                 return SMB_VFS_NEXT_LSTAT(handle, base, sbuf);
 192         }
 193
 194         if (SMB_VFS_LSTAT(handle->conn, base, sbuf) == -1) {
 195                 goto fail;
 196         }
 197
 198         xattr_name = talloc_asprintf(talloc_tos(), "%s%s",
 199                                      SAMBA_XATTR_DOSSTREAM_PREFIX, sname);
 200         if (xattr_name == NULL) {
 201                 errno = ENOMEM;
 202                 goto fail;
 203         }
 204
 205         sbuf->st_size = get_xattr_size(handle->conn, NULL, base, xattr_name);
 206         if (sbuf->st_size == -1) {
 207                 errno = ENOENT;
 208                 goto fail;
 209         }
 210
 211         sbuf->st_ino = stream_inode(sbuf, xattr_name);
 212         sbuf->st_mode &= ~S_IFMT;
 213         sbuf->st_mode |= S_IFREG;
 214         sbuf->st_blocks = sbuf->st_size % STAT_ST_BLOCKSIZE + 1;
 215
 216         result = 0;
 217  fail:
 218         TALLOC_FREE(base);
 219         TALLOC_FREE(sname);
 220         return result;
 221 }
 222
 223 static int streams_xattr_open(vfs_handle_struct *handle,  const char *fname,
 224                               files_struct *fsp, int flags, mode_t mode)
 225 {
 226         TALLOC_CTX *frame;
 227         NTSTATUS status;
 228         struct stream_io *sio;
 229         char *base, *sname;
 230         struct ea_struct ea;
 231         char *xattr_name;
 232         int baseflags;
 233         int hostfd = -1;
 234
 235         DEBUG(10, ("streams_xattr_open called for %s\n", fname));
 236
 237         if (!is_ntfs_stream_name(fname)) {
 238                 return SMB_VFS_NEXT_OPEN(handle, fname, fsp, flags, mode);
 239         }
 240
 241         frame = talloc_stackframe();
 242
 243         status = split_ntfs_stream_name(talloc_tos(), fname,
 244                                         &base, &sname);
 245         if (!NT_STATUS_IS_OK(status)) {
 246                 errno = EINVAL;
 247                 goto fail;
 248         }
 249
 250         if (sname == NULL) {
 251                 hostfd = SMB_VFS_NEXT_OPEN(handle, base, fsp, flags, mode);
 252                 talloc_free(frame);
 253                 return hostfd;
 254         }
 255
 256         xattr_name = talloc_asprintf(talloc_tos(), "%s%s",
 257                                      SAMBA_XATTR_DOSSTREAM_PREFIX, sname);
 258         if (xattr_name == NULL) {
 259                 errno = ENOMEM;
 260                 goto fail;
 261         }
 262
 263         /*
 264          * We use baseflags to turn off nasty side-effects when opening the
 265          * underlying file.
 266          */
 267         baseflags = flags;
 268         baseflags &= ~O_TRUNC;
 269         baseflags &= ~O_EXCL;
 270         baseflags &= ~O_CREAT;
 271
 272         hostfd = SMB_VFS_OPEN(handle->conn, base, fsp, baseflags, mode);
 273
 274         /* It is legit to open a stream on a directory, but the base
 275          * fd has to be read-only.
 276          */
 277         if ((hostfd == -1) && (errno == EISDIR)) {
 278                 baseflags &= ~O_ACCMODE;
 279                 baseflags |= O_RDONLY;
 280                 hostfd = SMB_VFS_OPEN(handle->conn, fname, fsp, baseflags,
 281                                       mode);
 282         }
 283
 284         if (hostfd == -1) {
 285                 goto fail;
 286         }
 287
 288         status = get_ea_value(talloc_tos(), handle->conn, NULL, base,
 289                               xattr_name, &ea);
 290
 291         DEBUG(10, ("get_ea_value returned %s\n", nt_errstr(status)));
 292
 293         if (!NT_STATUS_IS_OK(status)
 294             && !NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND)) {
 295                 /*
 296                  * The base file is not there. This is an error even if we got
 297                  * O_CREAT, the higher levels should have created the base
 298                  * file for us.
 299                  */
 300                 DEBUG(10, ("streams_xattr_open: base file %s not around, "
 301                            "returning ENOENT\n", base));
 302                 errno = ENOENT;
 303                 goto fail;
 304         }
 305
 306         if (!NT_STATUS_IS_OK(status)) {
 307                 /*
 308                  * The attribute does not exist
 309                  */
 310
 311                 if (flags & O_CREAT) {
 312                         /*
 313                          * Darn, xattrs need at least 1 byte
 314                          */
 315                         char null = '\0';
 316
 317                         DEBUG(10, ("creating attribute %s on file %s\n",
 318                                    xattr_name, base));
 319
 320                         if (fsp->base_fsp->fh->fd != -1) {
 321                                 if (SMB_VFS_FSETXATTR(
 322                                         fsp->base_fsp, xattr_name,
 323                                         &null, sizeof(null),
 324                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 325                                         goto fail;
 326                                 }
 327                         } else {
 328                                 if (SMB_VFS_SETXATTR(
 329                                         handle->conn, base, xattr_name,
 330                                         &null, sizeof(null),
 331                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 332                                         goto fail;
 333                                 }
 334                         }
 335                 }
 336         }
 337
 338         if (flags & O_TRUNC) {
 339                 char null = '\0';
 340                 if (fsp->base_fsp->fh->fd != -1) {
 341                         if (SMB_VFS_FSETXATTR(
 342                                         fsp->base_fsp, xattr_name,
 343                                         &null, sizeof(null),
 344                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 345                                 goto fail;
 346                         }
 347                 } else {
 348                         if (SMB_VFS_SETXATTR(
 349                                         handle->conn, base, xattr_name,
 350                                         &null, sizeof(null),
 351                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 352                                 goto fail;
 353                         }
 354                 }
 355         }
 356
 357         sio = (struct stream_io *)VFS_ADD_FSP_EXTENSION(handle, fsp,
 358                                                         struct stream_io);
 359         if (sio == NULL) {
 360                 errno = ENOMEM;
 361                 goto fail;
 362         }
 363
 364         sio->xattr_name = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(handle, fsp),
 365                                         xattr_name);
 366         sio->base = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(handle, fsp),
 367                                   base);
 368
 369         if ((sio->xattr_name == NULL) || (sio->base == NULL)) {
 370                 errno = ENOMEM;
 371                 goto fail;
 372         }
 373
 374         TALLOC_FREE(frame);
 375         return hostfd;
 376
 377  fail:
 378         if (hostfd >= 0) {
 379                 /*
 380                  * BUGBUGBUG -- we would need to call fd_close_posix here, but
 381                  * we don't have a full fsp yet
 382                  */
 383                 SMB_VFS_CLOSE(fsp);
 384         }
 385
 386         TALLOC_FREE(frame);
 387         return -1;
 388 }
 389
 390 static int streams_xattr_unlink(vfs_handle_struct *handle,  const char *fname)
 391 {
 392         NTSTATUS status;
 393         char *base = NULL;
 394         char *sname = NULL;
 395         int ret = -1;
 396         char *xattr_name;
 397
 398         if (!is_ntfs_stream_name(fname)) {
 399                 return SMB_VFS_NEXT_UNLINK(handle, fname);
 400         }
 401
 402         status = split_ntfs_stream_name(talloc_tos(), fname, &base, &sname);
 403         if (!NT_STATUS_IS_OK(status)) {
 404                 errno = EINVAL;
 405                 goto fail;
 406         }
 407
 408         if (sname == NULL){
 409                 return SMB_VFS_NEXT_UNLINK(handle, base);
 410         }
 411
 412         xattr_name = talloc_asprintf(talloc_tos(), "%s%s",
 413                                      SAMBA_XATTR_DOSSTREAM_PREFIX, sname);
 414         if (xattr_name == NULL) {
 415                 errno = ENOMEM;
 416                 goto fail;
 417         }
 418
 419         ret = SMB_VFS_REMOVEXATTR(handle->conn, base, xattr_name);
 420
 421         if ((ret == -1) && (errno == ENOATTR)) {
 422                 errno = ENOENT;
 423                 goto fail;
 424         }
 425
 426         ret = 0;
 427
 428  fail:
 429         TALLOC_FREE(base);
 430         TALLOC_FREE(sname);
 431         return ret;
 432 }
 433
 434 static int streams_xattr_rename(vfs_handle_struct *handle,
 435                                 const char *oldname,
 436                                 const char *newname)
 437 {
 438         NTSTATUS status;
 439         TALLOC_CTX *frame = NULL;
 440         char *obase;
 441         char *ostream;
 442         char *nbase;
 443         char *nstream;
 444         const char *base;
 445         int ret = -1;
 446         char *oxattr_name;
 447         char *nxattr_name;
 448         bool o_is_stream;
 449         bool n_is_stream;
 450         ssize_t oret;
 451         ssize_t nret;
 452         struct ea_struct ea;
 453
 454         o_is_stream = is_ntfs_stream_name(oldname);
 455         n_is_stream = is_ntfs_stream_name(newname);
 456
 457         if (!o_is_stream && !n_is_stream) {
 458                 return SMB_VFS_NEXT_RENAME(handle, oldname, newname);
 459         }
 460
 461         if (!(o_is_stream && n_is_stream)) {
 462                 errno = ENOSYS;
 463                 goto fail;
 464         }
 465
 466         frame = talloc_stackframe();
 467         if (!frame) {
 468                 goto fail;
 469         }
 470
 471         status = split_ntfs_stream_name(talloc_tos(), oldname, &obase, &ostream);
 472         if (!NT_STATUS_IS_OK(status)) {
 473                 errno = EINVAL;
 474                 goto fail;
 475         }
 476
 477         status = split_ntfs_stream_name(talloc_tos(), newname, &nbase, &nstream);
 478         if (!NT_STATUS_IS_OK(status)) {
 479                 errno = EINVAL;
 480                 goto fail;
 481         }
 482
 483         /*TODO: maybe call SMB_VFS_NEXT_RENAME() both streams are NULL (::$DATA) */
 484         if (ostream == NULL) {
 485                 errno = ENOSYS;
 486                 goto fail;
 487         }
 488
 489         if (nstream == NULL) {
 490                 errno = ENOSYS;
 491                 goto fail;
 492         }
 493
 494         /* the new base should be empty */
 495         if (StrCaseCmp(obase, nbase) != 0) {
 496                 errno = ENOSYS;
 497                 goto fail;
 498         }
 499
 500         if (StrCaseCmp(ostream, nstream) == 0) {
 501                 goto done;
 502         }
 503
 504         base = obase;
 505
 506         oxattr_name = talloc_asprintf(talloc_tos(), "%s%s",
 507                                       SAMBA_XATTR_DOSSTREAM_PREFIX, ostream);
 508         if (oxattr_name == NULL) {
 509                 errno = ENOMEM;
 510                 goto fail;
 511         }
 512
 513         nxattr_name = talloc_asprintf(talloc_tos(), "%s%s",
 514                                       SAMBA_XATTR_DOSSTREAM_PREFIX, nstream);
 515         if (nxattr_name == NULL) {
 516                 errno = ENOMEM;
 517                 goto fail;
 518         }
 519
 520         /* read the old stream */
 521         status = get_ea_value(talloc_tos(), handle->conn, NULL,
 522                               base, oxattr_name, &ea);
 523         if (!NT_STATUS_IS_OK(status)) {
 524                 errno = ENOENT;
 525                 goto fail;
 526         }
 527
 528         /* (over)write the new stream */
 529         nret = SMB_VFS_SETXATTR(handle->conn, base, nxattr_name,
 530                                 ea.value.data, ea.value.length, 0);
 531         if (nret < 0) {
 532                 if (errno == ENOATTR) {
 533                         errno = ENOENT;
 534                 }
 535                 goto fail;
 536         }
 537
 538         /* remove the old stream */
 539         oret = SMB_VFS_REMOVEXATTR(handle->conn, base, oxattr_name);
 540         if (oret < 0) {
 541                 if (errno == ENOATTR) {
 542                         errno = ENOENT;
 543                 }
 544                 goto fail;
 545         }
 546
 547  done:
 548         errno = 0;
 549         ret = 0;
 550  fail:
 551         TALLOC_FREE(frame);
 552         return ret;
 553 }
 554
 555 static NTSTATUS walk_xattr_streams(connection_struct *conn, files_struct *fsp,
 556                                    const char *fname,
 557                                    bool (*fn)(struct ea_struct *ea,
 558                                               void *private_data),
 559                                    void *private_data)
 560 {
 561         NTSTATUS status;
 562         char **names;
 563         size_t i, num_names;
 564         size_t prefix_len = strlen(SAMBA_XATTR_DOSSTREAM_PREFIX);
 565
 566         status = get_ea_names_from_file(talloc_tos(), conn, fsp, fname,
 567                                         &names, &num_names);
 568         if (!NT_STATUS_IS_OK(status)) {
 569                 return status;
 570         }
 571
 572         for (i=0; i<num_names; i++) {
 573                 struct ea_struct ea;
 574
 575                 if (strncmp(names[i], SAMBA_XATTR_DOSSTREAM_PREFIX,
 576                             prefix_len) != 0) {
 577                         continue;
 578                 }
 579
 580                 status = get_ea_value(names, conn, fsp, fname, names[i], &ea);
 581                 if (!NT_STATUS_IS_OK(status)) {
 582                         DEBUG(10, ("Could not get ea %s for file %s: %s\n",
 583                                    names[i], fname, nt_errstr(status)));
 584                         continue;
 585                 }
 586
 587                 ea.name = talloc_asprintf(ea.value.data, ":%s",
 588                                           names[i] + prefix_len);
 589                 if (ea.name == NULL) {
 590                         DEBUG(0, ("talloc failed\n"));
 591                         continue;
 592                 }
 593
 594                 if (!fn(&ea, private_data)) {
 595                         TALLOC_FREE(ea.value.data);
 596                         return NT_STATUS_OK;
 597                 }
 598
 599                 TALLOC_FREE(ea.value.data);
 600         }
 601
 602         TALLOC_FREE(names);
 603         return NT_STATUS_OK;
 604 }
 605
 606 static bool add_one_stream(TALLOC_CTX *mem_ctx, unsigned int *num_streams,
 607                            struct stream_struct **streams,
 608                            const char *name, SMB_OFF_T size,
 609                            SMB_OFF_T alloc_size)
 610 {
 611         struct stream_struct *tmp;
 612
 613         tmp = TALLOC_REALLOC_ARRAY(mem_ctx, *streams, struct stream_struct,
 614                                    (*num_streams)+1);
 615         if (tmp == NULL) {
 616                 return false;
 617         }
 618
 619         tmp[*num_streams].name = talloc_strdup(tmp, name);
 620         if (tmp[*num_streams].name == NULL) {
 621                 return false;
 622         }
 623
 624         tmp[*num_streams].size = size;
 625         tmp[*num_streams].alloc_size = alloc_size;
 626
 627         *streams = tmp;
 628         *num_streams += 1;
 629         return true;
 630 }
 631
 632 struct streaminfo_state {
 633         TALLOC_CTX *mem_ctx;
 634         vfs_handle_struct *handle;
 635         unsigned int num_streams;
 636         struct stream_struct *streams;
 637         NTSTATUS status;
 638 };
 639
 640 static bool collect_one_stream(struct ea_struct *ea, void *private_data)
 641 {
 642         struct streaminfo_state *state =
 643                 (struct streaminfo_state *)private_data;
 644
 645         if (!add_one_stream(state->mem_ctx,
 646                             &state->num_streams, &state->streams,
 647                             ea->name, ea->value.length-1,
 648                             smb_roundup(state->handle->conn,
 649                                         ea->value.length-1))) {
 650                 state->status = NT_STATUS_NO_MEMORY;
 651                 return false;
 652         }
 653
 654         return true;
 655 }
 656
 657 static NTSTATUS streams_xattr_streaminfo(vfs_handle_struct *handle,
 658                                          struct files_struct *fsp,
 659                                          const char *fname,
 660                                          TALLOC_CTX *mem_ctx,
 661                                          unsigned int *pnum_streams,
 662                                          struct stream_struct **pstreams)
 663 {
 664         SMB_STRUCT_STAT sbuf;
 665         int ret;
 666         NTSTATUS status;
 667         struct streaminfo_state state;
 668
 669         if ((fsp != NULL) && (fsp->fh->fd != -1)) {
 670                 if (is_ntfs_stream_name(fsp->fsp_name)) {
 671                         return NT_STATUS_INVALID_PARAMETER;
 672                 }
 673                 ret = SMB_VFS_FSTAT(fsp, &sbuf);
 674         }
 675         else {
 676                 if (is_ntfs_stream_name(fname)) {
 677                         return NT_STATUS_INVALID_PARAMETER;
 678                 }
 679                 ret = SMB_VFS_STAT(handle->conn, fname, &sbuf);
 680         }
 681
 682         if (ret == -1) {
 683                 return map_nt_error_from_unix(errno);
 684         }
 685
 686         state.streams = NULL;
 687         state.num_streams = 0;
 688
 689         if (!S_ISDIR(sbuf.st_mode)) {
 690                 if (!add_one_stream(mem_ctx,
 691                                     &state.num_streams, &state.streams,
 692                                     "::$DATA", sbuf.st_size,
 693                                     get_allocation_size(handle->conn, fsp,
 694                                                         &sbuf))) {
 695                         return NT_STATUS_NO_MEMORY;
 696                 }
 697         }
 698
 699         state.mem_ctx = mem_ctx;
 700         state.handle = handle;
 701         state.status = NT_STATUS_OK;
 702
 703         status = walk_xattr_streams(handle->conn, fsp, fname,
 704                                     collect_one_stream, &state);
 705
 706         if (!NT_STATUS_IS_OK(status)) {
 707                 TALLOC_FREE(state.streams);
 708                 return status;
 709         }
 710
 711         if (!NT_STATUS_IS_OK(state.status)) {
 712                 TALLOC_FREE(state.streams);
 713                 return state.status;
 714         }
 715
 716         *pnum_streams = state.num_streams;
 717         *pstreams = state.streams;
 718         return NT_STATUS_OK;
 719 }
 720
 721 static uint32_t streams_xattr_fs_capabilities(struct vfs_handle_struct *handle)
 722 {
 723         return SMB_VFS_NEXT_FS_CAPABILITIES(handle) | FILE_NAMED_STREAMS;
 724 }
 725
 726 static ssize_t streams_xattr_pwrite(vfs_handle_struct *handle,
 727                                     files_struct *fsp, const void *data,
 728                                     size_t n, SMB_OFF_T offset)
 729 {
 730         struct stream_io *sio =
 731                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
 732         struct ea_struct ea;
 733         NTSTATUS status;
 734         int ret;
 735
 736         DEBUG(10, ("streams_xattr_pwrite called for %d bytes\n", (int)n));
 737
 738         if (sio == NULL) {
 739                 return SMB_VFS_NEXT_PWRITE(handle, fsp, data, n, offset);
 740         }
 741
 742         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
 743                               sio->base, sio->xattr_name, &ea);
 744         if (!NT_STATUS_IS_OK(status)) {
 745                 return -1;
 746         }
 747
 748         if ((offset + n) > ea.value.length-1) {
 749                 uint8 *tmp;
 750
 751                 tmp = TALLOC_REALLOC_ARRAY(talloc_tos(), ea.value.data, uint8,
 752                                            offset + n + 1);
 753
 754                 if (tmp == NULL) {
 755                         TALLOC_FREE(ea.value.data);
 756                         errno = ENOMEM;
 757                         return -1;
 758                 }
 759                 ea.value.data = tmp;
 760                 ea.value.length = offset + n + 1;
 761                 ea.value.data[offset+n] = 0;
 762         }
 763
 764         memcpy(ea.value.data + offset, data, n);
 765
 766         if (fsp->base_fsp->fh->fd != -1) {
 767                 ret = SMB_VFS_FSETXATTR(fsp->base_fsp,
 768                                 sio->xattr_name,
 769                                 ea.value.data, ea.value.length, 0);
 770         } else {
 771                 ret = SMB_VFS_SETXATTR(fsp->conn, fsp->base_fsp->fsp_name,
 772                                 sio->xattr_name,
 773                                 ea.value.data, ea.value.length, 0);
 774         }
 775         TALLOC_FREE(ea.value.data);
 776
 777         if (ret == -1) {
 778                 return -1;
 779         }
 780
 781         return n;
 782 }
 783
 784 static ssize_t streams_xattr_pread(vfs_handle_struct *handle,
 785                                    files_struct *fsp, void *data,
 786                                    size_t n, SMB_OFF_T offset)
 787 {
 788         struct stream_io *sio =
 789                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
 790         struct ea_struct ea;
 791         NTSTATUS status;
 792         size_t length, overlap;
 793
 794         if (sio == NULL) {
 795                 return SMB_VFS_NEXT_PREAD(handle, fsp, data, n, offset);
 796         }
 797
 798         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
 799                               sio->base, sio->xattr_name, &ea);
 800         if (!NT_STATUS_IS_OK(status)) {
 801                 return -1;
 802         }
 803
 804         length = ea.value.length-1;
 805
 806         /* Attempt to read past EOF. */
 807         if (length <= offset) {
 808                 errno = EINVAL;
 809                 return -1;
 810         }
 811
 812         overlap = (offset + n) > length ? (length - offset) : n;
 813         memcpy(data, ea.value.data + offset, overlap);
 814
 815         TALLOC_FREE(ea.value.data);
 816         return overlap;
 817 }
 818
 819 static int streams_xattr_ftruncate(struct vfs_handle_struct *handle,
 820                                         struct files_struct *fsp,
 821                                         SMB_OFF_T offset)
 822 {
 823         int ret;
 824         uint8 *tmp;
 825         struct ea_struct ea;
 826         NTSTATUS status;
 827         struct stream_io *sio =
 828                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
 829
 830         DEBUG(10, ("streams_xattr_ftruncate called for file %s offset %.0f\n",
 831                 fsp->fsp_name,
 832                 (double)offset ));
 833
 834         if (sio == NULL) {
 835                 return SMB_VFS_NEXT_FTRUNCATE(handle, fsp, offset);
 836         }
 837
 838         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
 839                               sio->base, sio->xattr_name, &ea);
 840         if (!NT_STATUS_IS_OK(status)) {
 841                 return -1;
 842         }
 843
 844         tmp = TALLOC_REALLOC_ARRAY(talloc_tos(), ea.value.data, uint8,
 845                                    offset + 1);
 846
 847         if (tmp == NULL) {
 848                 TALLOC_FREE(ea.value.data);
 849                 errno = ENOMEM;
 850                 return -1;
 851         }
 852
 853         /* Did we expand ? */
 854         if (ea.value.length < offset + 1) {
 855                 memset(&tmp[ea.value.length], '\0',
 856                         offset + 1 - ea.value.length);
 857         }
 858
 859         ea.value.data = tmp;
 860         ea.value.length = offset + 1;
 861         ea.value.data[offset] = 0;
 862
 863         if (fsp->base_fsp->fh->fd != -1) {
 864                 ret = SMB_VFS_FSETXATTR(fsp->base_fsp,
 865                                 sio->xattr_name,
 866                                 ea.value.data, ea.value.length, 0);
 867         } else {
 868                 ret = SMB_VFS_SETXATTR(fsp->conn, fsp->base_fsp->fsp_name,
 869                                 sio->xattr_name,
 870                                 ea.value.data, ea.value.length, 0);
 871         }
 872
 873         TALLOC_FREE(ea.value.data);
 874
 875         if (ret == -1) {
 876                 return -1;
 877         }
 878
 879         return 0;
 880 }
 881
 882 /* VFS operations structure */
 883
 884 static vfs_op_tuple streams_xattr_ops[] = {
 885         {SMB_VFS_OP(streams_xattr_fs_capabilities), SMB_VFS_OP_FS_CAPABILITIES,
 886          SMB_VFS_LAYER_TRANSPARENT},
 887         {SMB_VFS_OP(streams_xattr_open), SMB_VFS_OP_OPEN,
 888          SMB_VFS_LAYER_TRANSPARENT},
 889         {SMB_VFS_OP(streams_xattr_stat), SMB_VFS_OP_STAT,
 890          SMB_VFS_LAYER_TRANSPARENT},
 891         {SMB_VFS_OP(streams_xattr_fstat), SMB_VFS_OP_FSTAT,
 892          SMB_VFS_LAYER_TRANSPARENT},
 893         {SMB_VFS_OP(streams_xattr_lstat), SMB_VFS_OP_LSTAT,
 894          SMB_VFS_LAYER_TRANSPARENT},
 895         {SMB_VFS_OP(streams_xattr_pread), SMB_VFS_OP_PREAD,
 896          SMB_VFS_LAYER_TRANSPARENT},
 897         {SMB_VFS_OP(streams_xattr_pwrite), SMB_VFS_OP_PWRITE,
 898          SMB_VFS_LAYER_TRANSPARENT},
 899         {SMB_VFS_OP(streams_xattr_lstat), SMB_VFS_OP_LSTAT,
 900          SMB_VFS_LAYER_TRANSPARENT},
 901         {SMB_VFS_OP(streams_xattr_unlink), SMB_VFS_OP_UNLINK,
 902          SMB_VFS_LAYER_TRANSPARENT},
 903         {SMB_VFS_OP(streams_xattr_rename), SMB_VFS_OP_RENAME,
 904          SMB_VFS_LAYER_TRANSPARENT},
 905         {SMB_VFS_OP(streams_xattr_ftruncate),  SMB_VFS_OP_FTRUNCATE,
 906          SMB_VFS_LAYER_TRANSPARENT},
 907         {SMB_VFS_OP(streams_xattr_streaminfo), SMB_VFS_OP_STREAMINFO,
 908          SMB_VFS_LAYER_OPAQUE},
 909         {SMB_VFS_OP(NULL), SMB_VFS_OP_NOOP, SMB_VFS_LAYER_NOOP}
 910 };
 911
 912 NTSTATUS vfs_streams_xattr_init(void);
 913 NTSTATUS vfs_streams_xattr_init(void)
 914 {
 915         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "streams_xattr",
 916                                 streams_xattr_ops);
 917 }