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 #include "smbd/smbd.h"
  26 #include "system/filesys.h"
  27 #include "../lib/crypto/md5.h"
  28
  29 #undef DBGC_CLASS
  30 #define DBGC_CLASS DBGC_VFS
  31
  32 struct stream_io {
  33         char *base;
  34         char *xattr_name;
  35         void *fsp_name_ptr;
  36         files_struct *fsp;
  37         vfs_handle_struct *handle;
  38 };
  39
  40 static SMB_INO_T stream_inode(const SMB_STRUCT_STAT *sbuf, const char *sname)
  41 {
  42         struct MD5Context ctx;
  43         unsigned char hash[16];
  44         SMB_INO_T result;
  45         char *upper_sname;
  46
  47         DEBUG(10, ("stream_inode called for %lu/%lu [%s]\n",
  48                    (unsigned long)sbuf->st_ex_dev,
  49                    (unsigned long)sbuf->st_ex_ino, sname));
  50
  51         upper_sname = talloc_strdup_upper(talloc_tos(), sname);
  52         SMB_ASSERT(upper_sname != NULL);
  53
  54         MD5Init(&ctx);
  55         MD5Update(&ctx, (const unsigned char *)&(sbuf->st_ex_dev),
  56                   sizeof(sbuf->st_ex_dev));
  57         MD5Update(&ctx, (const unsigned char *)&(sbuf->st_ex_ino),
  58                   sizeof(sbuf->st_ex_ino));
  59         MD5Update(&ctx, (unsigned char *)upper_sname,
  60                   talloc_get_size(upper_sname)-1);
  61         MD5Final(hash, &ctx);
  62
  63         TALLOC_FREE(upper_sname);
  64
  65         /* Hopefully all the variation is in the lower 4 (or 8) bytes! */
  66         memcpy(&result, hash, sizeof(result));
  67
  68         DEBUG(10, ("stream_inode returns %lu\n", (unsigned long)result));
  69
  70         return result;
  71 }
  72
  73 static ssize_t get_xattr_size(connection_struct *conn,
  74                                 files_struct *fsp,
  75                                 const char *fname,
  76                                 const char *xattr_name)
  77 {
  78         NTSTATUS status;
  79         struct ea_struct ea;
  80         ssize_t result;
  81
  82         status = get_ea_value(talloc_tos(), conn, fsp, fname,
  83                               xattr_name, &ea);
  84
  85         if (!NT_STATUS_IS_OK(status)) {
  86                 return -1;
  87         }
  88
  89         result = ea.value.length-1;
  90         TALLOC_FREE(ea.value.data);
  91         return result;
  92 }
  93
  94 /**
  95  * Given a stream name, populate xattr_name with the xattr name to use for
  96  * accessing the stream.
  97  */
  98 static NTSTATUS streams_xattr_get_name(TALLOC_CTX *ctx,
  99                                        const char *stream_name,
 100                                        char **xattr_name)
 101 {
 102         char *stype;
 103
 104         stype = strchr_m(stream_name + 1, ':');
 105
 106         *xattr_name = talloc_asprintf(ctx, "%s%s",
 107                                       SAMBA_XATTR_DOSSTREAM_PREFIX,
 108                                       stream_name + 1);
 109         if (*xattr_name == NULL) {
 110                 return NT_STATUS_NO_MEMORY;
 111         }
 112
 113         if (stype == NULL) {
 114                 /* Append an explicit stream type if one wasn't specified. */
 115                 *xattr_name = talloc_asprintf(ctx, "%s:$DATA",
 116                                                *xattr_name);
 117                 if (*xattr_name == NULL) {
 118                         return NT_STATUS_NO_MEMORY;
 119                 }
 120         } else {
 121                 /* Normalize the stream type to upercase. */
 122                 if (!strupper_m(strrchr_m(*xattr_name, ':') + 1)) {
 123                         return NT_STATUS_INVALID_PARAMETER;
 124                 }
 125         }
 126
 127         DEBUG(10, ("xattr_name: %s, stream_name: %s\n", *xattr_name,
 128                    stream_name));
 129
 130         return NT_STATUS_OK;
 131 }
 132
 133 static bool streams_xattr_recheck(struct stream_io *sio)
 134 {
 135         NTSTATUS status;
 136         char *xattr_name = NULL;
 137
 138         if (sio->fsp->fsp_name == sio->fsp_name_ptr) {
 139                 return true;
 140         }
 141
 142         if (sio->fsp->fsp_name->stream_name == NULL) {
 143                 /* how can this happen */
 144                 errno = EINVAL;
 145                 return false;
 146         }
 147
 148         status = streams_xattr_get_name(talloc_tos(),
 149                                         sio->fsp->fsp_name->stream_name,
 150                                         &xattr_name);
 151         if (!NT_STATUS_IS_OK(status)) {
 152                 return false;
 153         }
 154
 155         TALLOC_FREE(sio->xattr_name);
 156         TALLOC_FREE(sio->base);
 157         sio->xattr_name = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(sio->handle, sio->fsp),
 158                                         xattr_name);
 159         sio->base = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(sio->handle, sio->fsp),
 160                                   sio->fsp->fsp_name->base_name);
 161         sio->fsp_name_ptr = sio->fsp->fsp_name;
 162
 163         TALLOC_FREE(xattr_name);
 164
 165         if ((sio->xattr_name == NULL) || (sio->base == NULL)) {
 166                 return false;
 167         }
 168
 169         return true;
 170 }
 171
 172 /**
 173  * Helper to stat/lstat the base file of an smb_fname.
 174  */
 175 static int streams_xattr_stat_base(vfs_handle_struct *handle,
 176                                    struct smb_filename *smb_fname,
 177                                    bool follow_links)
 178 {
 179         char *tmp_stream_name;
 180         int result;
 181
 182         tmp_stream_name = smb_fname->stream_name;
 183         smb_fname->stream_name = NULL;
 184         if (follow_links) {
 185                 result = SMB_VFS_NEXT_STAT(handle, smb_fname);
 186         } else {
 187                 result = SMB_VFS_NEXT_LSTAT(handle, smb_fname);
 188         }
 189         smb_fname->stream_name = tmp_stream_name;
 190         return result;
 191 }
 192
 193 static int streams_xattr_fstat(vfs_handle_struct *handle, files_struct *fsp,
 194                                SMB_STRUCT_STAT *sbuf)
 195 {
 196         struct smb_filename *smb_fname_base = NULL;
 197         NTSTATUS status;
 198         int ret = -1;
 199         struct stream_io *io = (struct stream_io *)
 200                 VFS_FETCH_FSP_EXTENSION(handle, fsp);
 201
 202         DEBUG(10, ("streams_xattr_fstat called for %d\n", fsp->fh->fd));
 203
 204         if (io == NULL || fsp->base_fsp == NULL) {
 205                 return SMB_VFS_NEXT_FSTAT(handle, fsp, sbuf);
 206         }
 207
 208         if (!streams_xattr_recheck(io)) {
 209                 return -1;
 210         }
 211
 212         /* Create an smb_filename with stream_name == NULL. */
 213         status = create_synthetic_smb_fname(talloc_tos(),
 214                                             io->base,
 215                                             NULL, NULL,
 216                                             &smb_fname_base);
 217         if (!NT_STATUS_IS_OK(status)) {
 218                 errno = map_errno_from_nt_status(status);
 219                 return -1;
 220         }
 221
 222         if (lp_posix_pathnames()) {
 223                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_base);
 224         } else {
 225                 ret = SMB_VFS_STAT(handle->conn, smb_fname_base);
 226         }
 227         *sbuf = smb_fname_base->st;
 228         TALLOC_FREE(smb_fname_base);
 229
 230         if (ret == -1) {
 231                 return -1;
 232         }
 233
 234         sbuf->st_ex_size = get_xattr_size(handle->conn, fsp->base_fsp,
 235                                         io->base, io->xattr_name);
 236         if (sbuf->st_ex_size == -1) {
 237                 return -1;
 238         }
 239
 240         DEBUG(10, ("sbuf->st_ex_size = %d\n", (int)sbuf->st_ex_size));
 241
 242         sbuf->st_ex_ino = stream_inode(sbuf, io->xattr_name);
 243         sbuf->st_ex_mode &= ~S_IFMT;
 244         sbuf->st_ex_mode |= S_IFREG;
 245         sbuf->st_ex_blocks = sbuf->st_ex_size / STAT_ST_BLOCKSIZE + 1;
 246
 247         return 0;
 248 }
 249
 250 static int streams_xattr_stat(vfs_handle_struct *handle,
 251                               struct smb_filename *smb_fname)
 252 {
 253         NTSTATUS status;
 254         int result = -1;
 255         char *xattr_name = NULL;
 256
 257         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 258                 return SMB_VFS_NEXT_STAT(handle, smb_fname);
 259         }
 260
 261         /* Note if lp_posix_paths() is true, we can never
 262          * get here as is_ntfs_stream_smb_fname() is
 263          * always false. So we never need worry about
 264          * not following links here. */
 265
 266         /* If the default stream is requested, just stat the base file. */
 267         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 268                 return streams_xattr_stat_base(handle, smb_fname, true);
 269         }
 270
 271         /* Populate the stat struct with info from the base file. */
 272         if (streams_xattr_stat_base(handle, smb_fname, true) == -1) {
 273                 return -1;
 274         }
 275
 276         /* Derive the xattr name to lookup. */
 277         status = streams_xattr_get_name(talloc_tos(), smb_fname->stream_name,
 278                                         &xattr_name);
 279         if (!NT_STATUS_IS_OK(status)) {
 280                 errno = map_errno_from_nt_status(status);
 281                 return -1;
 282         }
 283
 284         /* Augment the base file's stat information before returning. */
 285         smb_fname->st.st_ex_size = get_xattr_size(handle->conn, NULL,
 286                                                   smb_fname->base_name,
 287                                                   xattr_name);
 288         if (smb_fname->st.st_ex_size == -1) {
 289                 errno = ENOENT;
 290                 result = -1;
 291                 goto fail;
 292         }
 293
 294         smb_fname->st.st_ex_ino = stream_inode(&smb_fname->st, xattr_name);
 295         smb_fname->st.st_ex_mode &= ~S_IFMT;
 296         smb_fname->st.st_ex_mode |= S_IFREG;
 297         smb_fname->st.st_ex_blocks =
 298             smb_fname->st.st_ex_size / STAT_ST_BLOCKSIZE + 1;
 299
 300         result = 0;
 301  fail:
 302         TALLOC_FREE(xattr_name);
 303         return result;
 304 }
 305
 306 static int streams_xattr_lstat(vfs_handle_struct *handle,
 307                                struct smb_filename *smb_fname)
 308 {
 309         NTSTATUS status;
 310         int result = -1;
 311         char *xattr_name = NULL;
 312
 313         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 314                 return SMB_VFS_NEXT_LSTAT(handle, smb_fname);
 315         }
 316
 317         /* If the default stream is requested, just stat the base file. */
 318         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 319                 return streams_xattr_stat_base(handle, smb_fname, false);
 320         }
 321
 322         /* Populate the stat struct with info from the base file. */
 323         if (streams_xattr_stat_base(handle, smb_fname, false) == -1) {
 324                 return -1;
 325         }
 326
 327         /* Derive the xattr name to lookup. */
 328         status = streams_xattr_get_name(talloc_tos(), smb_fname->stream_name,
 329                                         &xattr_name);
 330         if (!NT_STATUS_IS_OK(status)) {
 331                 errno = map_errno_from_nt_status(status);
 332                 return -1;
 333         }
 334
 335         /* Augment the base file's stat information before returning. */
 336         smb_fname->st.st_ex_size = get_xattr_size(handle->conn, NULL,
 337                                                   smb_fname->base_name,
 338                                                   xattr_name);
 339         if (smb_fname->st.st_ex_size == -1) {
 340                 errno = ENOENT;
 341                 result = -1;
 342                 goto fail;
 343         }
 344
 345         smb_fname->st.st_ex_ino = stream_inode(&smb_fname->st, xattr_name);
 346         smb_fname->st.st_ex_mode &= ~S_IFMT;
 347         smb_fname->st.st_ex_mode |= S_IFREG;
 348         smb_fname->st.st_ex_blocks =
 349             smb_fname->st.st_ex_size / STAT_ST_BLOCKSIZE + 1;
 350
 351         result = 0;
 352
 353  fail:
 354         TALLOC_FREE(xattr_name);
 355         return result;
 356 }
 357
 358 static int streams_xattr_open(vfs_handle_struct *handle,
 359                               struct smb_filename *smb_fname,
 360                               files_struct *fsp, int flags, mode_t mode)
 361 {
 362         NTSTATUS status;
 363         struct smb_filename *smb_fname_base = NULL;
 364         struct stream_io *sio;
 365         struct ea_struct ea;
 366         char *xattr_name = NULL;
 367         int baseflags;
 368         int hostfd = -1;
 369
 370         DEBUG(10, ("streams_xattr_open called for %s\n",
 371                    smb_fname_str_dbg(smb_fname)));
 372
 373         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 374                 return SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
 375         }
 376
 377         /* If the default stream is requested, just open the base file. */
 378         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 379                 char *tmp_stream_name;
 380                 int ret;
 381
 382                 tmp_stream_name = smb_fname->stream_name;
 383                 smb_fname->stream_name = NULL;
 384
 385                 ret = SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
 386
 387                 smb_fname->stream_name = tmp_stream_name;
 388
 389                 return ret;
 390         }
 391
 392         status = streams_xattr_get_name(talloc_tos(), smb_fname->stream_name,
 393                                         &xattr_name);
 394         if (!NT_STATUS_IS_OK(status)) {
 395                 errno = map_errno_from_nt_status(status);
 396                 goto fail;
 397         }
 398
 399         /* Create an smb_filename with stream_name == NULL. */
 400         status = create_synthetic_smb_fname(talloc_tos(),
 401                                             smb_fname->base_name,
 402                                             NULL, NULL,
 403                                             &smb_fname_base);
 404         if (!NT_STATUS_IS_OK(status)) {
 405                 errno = map_errno_from_nt_status(status);
 406                 goto fail;
 407         }
 408
 409         /*
 410          * We use baseflags to turn off nasty side-effects when opening the
 411          * underlying file.
 412          */
 413         baseflags = flags;
 414         baseflags &= ~O_TRUNC;
 415         baseflags &= ~O_EXCL;
 416         baseflags &= ~O_CREAT;
 417
 418         hostfd = SMB_VFS_OPEN(handle->conn, smb_fname_base, fsp,
 419                               baseflags, mode);
 420
 421         TALLOC_FREE(smb_fname_base);
 422
 423         /* It is legit to open a stream on a directory, but the base
 424          * fd has to be read-only.
 425          */
 426         if ((hostfd == -1) && (errno == EISDIR)) {
 427                 baseflags &= ~O_ACCMODE;
 428                 baseflags |= O_RDONLY;
 429                 hostfd = SMB_VFS_OPEN(handle->conn, smb_fname, fsp, baseflags,
 430                                       mode);
 431         }
 432
 433         if (hostfd == -1) {
 434                 goto fail;
 435         }
 436
 437         status = get_ea_value(talloc_tos(), handle->conn, NULL,
 438                               smb_fname->base_name, xattr_name, &ea);
 439
 440         DEBUG(10, ("get_ea_value returned %s\n", nt_errstr(status)));
 441
 442         if (!NT_STATUS_IS_OK(status)
 443             && !NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND)) {
 444                 /*
 445                  * The base file is not there. This is an error even if we got
 446                  * O_CREAT, the higher levels should have created the base
 447                  * file for us.
 448                  */
 449                 DEBUG(10, ("streams_xattr_open: base file %s not around, "
 450                            "returning ENOENT\n", smb_fname->base_name));
 451                 errno = ENOENT;
 452                 goto fail;
 453         }
 454
 455         if (!NT_STATUS_IS_OK(status)) {
 456                 /*
 457                  * The attribute does not exist
 458                  */
 459
 460                 if (flags & O_CREAT) {
 461                         /*
 462                          * Darn, xattrs need at least 1 byte
 463                          */
 464                         char null = '\0';
 465
 466                         DEBUG(10, ("creating attribute %s on file %s\n",
 467                                    xattr_name, smb_fname->base_name));
 468
 469                         if (fsp->base_fsp->fh->fd != -1) {
 470                                 if (SMB_VFS_FSETXATTR(
 471                                         fsp->base_fsp, xattr_name,
 472                                         &null, sizeof(null),
 473                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 474                                         goto fail;
 475                                 }
 476                         } else {
 477                                 if (SMB_VFS_SETXATTR(
 478                                         handle->conn, smb_fname->base_name,
 479                                         xattr_name, &null, sizeof(null),
 480                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 481                                         goto fail;
 482                                 }
 483                         }
 484                 }
 485         }
 486
 487         if (flags & O_TRUNC) {
 488                 char null = '\0';
 489                 if (fsp->base_fsp->fh->fd != -1) {
 490                         if (SMB_VFS_FSETXATTR(
 491                                         fsp->base_fsp, xattr_name,
 492                                         &null, sizeof(null),
 493                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 494                                 goto fail;
 495                         }
 496                 } else {
 497                         if (SMB_VFS_SETXATTR(
 498                                         handle->conn, smb_fname->base_name,
 499                                         xattr_name, &null, sizeof(null),
 500                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 501                                 goto fail;
 502                         }
 503                 }
 504         }
 505
 506         sio = (struct stream_io *)VFS_ADD_FSP_EXTENSION(handle, fsp,
 507                                                         struct stream_io,
 508                                                         NULL);
 509         if (sio == NULL) {
 510                 errno = ENOMEM;
 511                 goto fail;
 512         }
 513
 514         sio->xattr_name = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(handle, fsp),
 515                                         xattr_name);
 516         sio->base = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(handle, fsp),
 517                                   smb_fname->base_name);
 518         sio->fsp_name_ptr = fsp->fsp_name;
 519         sio->handle = handle;
 520         sio->fsp = fsp;
 521
 522         if ((sio->xattr_name == NULL) || (sio->base == NULL)) {
 523                 errno = ENOMEM;
 524                 goto fail;
 525         }
 526
 527         return hostfd;
 528
 529  fail:
 530         if (hostfd >= 0) {
 531                 /*
 532                  * BUGBUGBUG -- we would need to call fd_close_posix here, but
 533                  * we don't have a full fsp yet
 534                  */
 535                 SMB_VFS_CLOSE(fsp);
 536         }
 537
 538         return -1;
 539 }
 540
 541 static int streams_xattr_unlink(vfs_handle_struct *handle,
 542                                 const struct smb_filename *smb_fname)
 543 {
 544         NTSTATUS status;
 545         int ret = -1;
 546         char *xattr_name;
 547
 548         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 549                 return SMB_VFS_NEXT_UNLINK(handle, smb_fname);
 550         }
 551
 552         /* If the default stream is requested, just open the base file. */
 553         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 554                 struct smb_filename *smb_fname_base = NULL;
 555
 556                 status = copy_smb_filename(talloc_tos(), smb_fname,
 557                                             &smb_fname_base);
 558                 if (!NT_STATUS_IS_OK(status)) {
 559                         errno = map_errno_from_nt_status(status);
 560                         return -1;
 561                 }
 562
 563                 ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname_base);
 564
 565                 TALLOC_FREE(smb_fname_base);
 566                 return ret;
 567         }
 568
 569         status = streams_xattr_get_name(talloc_tos(), smb_fname->stream_name,
 570                                         &xattr_name);
 571         if (!NT_STATUS_IS_OK(status)) {
 572                 errno = map_errno_from_nt_status(status);
 573                 goto fail;
 574         }
 575
 576         ret = SMB_VFS_REMOVEXATTR(handle->conn, smb_fname->base_name, xattr_name);
 577
 578         if ((ret == -1) && (errno == ENOATTR)) {
 579                 errno = ENOENT;
 580                 goto fail;
 581         }
 582
 583         ret = 0;
 584
 585  fail:
 586         TALLOC_FREE(xattr_name);
 587         return ret;
 588 }
 589
 590 static int streams_xattr_rename(vfs_handle_struct *handle,
 591                                 const struct smb_filename *smb_fname_src,
 592                                 const struct smb_filename *smb_fname_dst)
 593 {
 594         NTSTATUS status;
 595         int ret = -1;
 596         char *src_xattr_name = NULL;
 597         char *dst_xattr_name = NULL;
 598         bool src_is_stream, dst_is_stream;
 599         ssize_t oret;
 600         ssize_t nret;
 601         struct ea_struct ea;
 602
 603         src_is_stream = is_ntfs_stream_smb_fname(smb_fname_src);
 604         dst_is_stream = is_ntfs_stream_smb_fname(smb_fname_dst);
 605
 606         if (!src_is_stream && !dst_is_stream) {
 607                 return SMB_VFS_NEXT_RENAME(handle, smb_fname_src,
 608                                            smb_fname_dst);
 609         }
 610
 611         /* For now don't allow renames from or to the default stream. */
 612         if (is_ntfs_default_stream_smb_fname(smb_fname_src) ||
 613             is_ntfs_default_stream_smb_fname(smb_fname_dst)) {
 614                 errno = ENOSYS;
 615                 goto done;
 616         }
 617
 618         /* Don't rename if the streams are identical. */
 619         if (strcasecmp_m(smb_fname_src->stream_name,
 620                        smb_fname_dst->stream_name) == 0) {
 621                 goto done;
 622         }
 623
 624         /* Get the xattr names. */
 625         status = streams_xattr_get_name(talloc_tos(),
 626                                         smb_fname_src->stream_name,
 627                                         &src_xattr_name);
 628         if (!NT_STATUS_IS_OK(status)) {
 629                 errno = map_errno_from_nt_status(status);
 630                 goto fail;
 631         }
 632         status = streams_xattr_get_name(talloc_tos(),
 633                                         smb_fname_dst->stream_name,
 634                                         &dst_xattr_name);
 635         if (!NT_STATUS_IS_OK(status)) {
 636                 errno = map_errno_from_nt_status(status);
 637                 goto fail;
 638         }
 639
 640         /* read the old stream */
 641         status = get_ea_value(talloc_tos(), handle->conn, NULL,
 642                               smb_fname_src->base_name, src_xattr_name, &ea);
 643         if (!NT_STATUS_IS_OK(status)) {
 644                 errno = ENOENT;
 645                 goto fail;
 646         }
 647
 648         /* (over)write the new stream */
 649         nret = SMB_VFS_SETXATTR(handle->conn, smb_fname_src->base_name,
 650                                 dst_xattr_name, ea.value.data, ea.value.length,
 651                                 0);
 652         if (nret < 0) {
 653                 if (errno == ENOATTR) {
 654                         errno = ENOENT;
 655                 }
 656                 goto fail;
 657         }
 658
 659         /* remove the old stream */
 660         oret = SMB_VFS_REMOVEXATTR(handle->conn, smb_fname_src->base_name,
 661                                    src_xattr_name);
 662         if (oret < 0) {
 663                 if (errno == ENOATTR) {
 664                         errno = ENOENT;
 665                 }
 666                 goto fail;
 667         }
 668
 669  done:
 670         errno = 0;
 671         ret = 0;
 672  fail:
 673         TALLOC_FREE(src_xattr_name);
 674         TALLOC_FREE(dst_xattr_name);
 675         return ret;
 676 }
 677
 678 static NTSTATUS walk_xattr_streams(connection_struct *conn, files_struct *fsp,
 679                                    const char *fname,
 680                                    bool (*fn)(struct ea_struct *ea,
 681                                               void *private_data),
 682                                    void *private_data)
 683 {
 684         NTSTATUS status;
 685         char **names;
 686         size_t i, num_names;
 687         size_t prefix_len = strlen(SAMBA_XATTR_DOSSTREAM_PREFIX);
 688
 689         status = get_ea_names_from_file(talloc_tos(), conn, fsp, fname,
 690                                         &names, &num_names);
 691         if (!NT_STATUS_IS_OK(status)) {
 692                 return status;
 693         }
 694
 695         for (i=0; i<num_names; i++) {
 696                 struct ea_struct ea;
 697
 698                 if (strncmp(names[i], SAMBA_XATTR_DOSSTREAM_PREFIX,
 699                             prefix_len) != 0) {
 700                         continue;
 701                 }
 702
 703                 status = get_ea_value(names, conn, fsp, fname, names[i], &ea);
 704                 if (!NT_STATUS_IS_OK(status)) {
 705                         DEBUG(10, ("Could not get ea %s for file %s: %s\n",
 706                                    names[i], fname, nt_errstr(status)));
 707                         continue;
 708                 }
 709
 710                 ea.name = talloc_asprintf(ea.value.data, ":%s",
 711                                           names[i] + prefix_len);
 712                 if (ea.name == NULL) {
 713                         DEBUG(0, ("talloc failed\n"));
 714                         continue;
 715                 }
 716
 717                 if (!fn(&ea, private_data)) {
 718                         TALLOC_FREE(ea.value.data);
 719                         return NT_STATUS_OK;
 720                 }
 721
 722                 TALLOC_FREE(ea.value.data);
 723         }
 724
 725         TALLOC_FREE(names);
 726         return NT_STATUS_OK;
 727 }
 728
 729 static bool add_one_stream(TALLOC_CTX *mem_ctx, unsigned int *num_streams,
 730                            struct stream_struct **streams,
 731                            const char *name, off_t size,
 732                            off_t alloc_size)
 733 {
 734         struct stream_struct *tmp;
 735
 736         tmp = talloc_realloc(mem_ctx, *streams, struct stream_struct,
 737                                    (*num_streams)+1);
 738         if (tmp == NULL) {
 739                 return false;
 740         }
 741
 742         tmp[*num_streams].name = talloc_strdup(tmp, name);
 743         if (tmp[*num_streams].name == NULL) {
 744                 return false;
 745         }
 746
 747         tmp[*num_streams].size = size;
 748         tmp[*num_streams].alloc_size = alloc_size;
 749
 750         *streams = tmp;
 751         *num_streams += 1;
 752         return true;
 753 }
 754
 755 struct streaminfo_state {
 756         TALLOC_CTX *mem_ctx;
 757         vfs_handle_struct *handle;
 758         unsigned int num_streams;
 759         struct stream_struct *streams;
 760         NTSTATUS status;
 761 };
 762
 763 static bool collect_one_stream(struct ea_struct *ea, void *private_data)
 764 {
 765         struct streaminfo_state *state =
 766                 (struct streaminfo_state *)private_data;
 767
 768         if (!add_one_stream(state->mem_ctx,
 769                             &state->num_streams, &state->streams,
 770                             ea->name, ea->value.length-1,
 771                             smb_roundup(state->handle->conn,
 772                                         ea->value.length-1))) {
 773                 state->status = NT_STATUS_NO_MEMORY;
 774                 return false;
 775         }
 776
 777         return true;
 778 }
 779
 780 static NTSTATUS streams_xattr_streaminfo(vfs_handle_struct *handle,
 781                                          struct files_struct *fsp,
 782                                          const char *fname,
 783                                          TALLOC_CTX *mem_ctx,
 784                                          unsigned int *pnum_streams,
 785                                          struct stream_struct **pstreams)
 786 {
 787         SMB_STRUCT_STAT sbuf;
 788         int ret;
 789         NTSTATUS status;
 790         struct streaminfo_state state;
 791
 792         if ((fsp != NULL) && (fsp->fh->fd != -1)) {
 793                 ret = SMB_VFS_FSTAT(fsp, &sbuf);
 794         }
 795         else {
 796                 struct smb_filename *smb_fname = NULL;
 797                 status = create_synthetic_smb_fname(talloc_tos(), fname, NULL,
 798                                                     NULL, &smb_fname);
 799                 if (!NT_STATUS_IS_OK(status)) {
 800                         return status;
 801                 }
 802                 if (lp_posix_pathnames()) {
 803                         ret = SMB_VFS_LSTAT(handle->conn, smb_fname);
 804                 } else {
 805                         ret = SMB_VFS_STAT(handle->conn, smb_fname);
 806                 }
 807                 sbuf = smb_fname->st;
 808                 TALLOC_FREE(smb_fname);
 809         }
 810
 811         if (ret == -1) {
 812                 return map_nt_error_from_unix(errno);
 813         }
 814
 815         state.streams = *pstreams;
 816         state.num_streams = *pnum_streams;
 817         state.mem_ctx = mem_ctx;
 818         state.handle = handle;
 819         state.status = NT_STATUS_OK;
 820
 821         status = walk_xattr_streams(handle->conn, fsp, fname,
 822                                     collect_one_stream, &state);
 823
 824         if (!NT_STATUS_IS_OK(status)) {
 825                 TALLOC_FREE(state.streams);
 826                 return status;
 827         }
 828
 829         if (!NT_STATUS_IS_OK(state.status)) {
 830                 TALLOC_FREE(state.streams);
 831                 return state.status;
 832         }
 833
 834         *pnum_streams = state.num_streams;
 835         *pstreams = state.streams;
 836
 837         return SMB_VFS_NEXT_STREAMINFO(handle, fsp, fname, mem_ctx, pnum_streams, pstreams);
 838 }
 839
 840 static uint32_t streams_xattr_fs_capabilities(struct vfs_handle_struct *handle,
 841                         enum timestamp_set_resolution *p_ts_res)
 842 {
 843         return SMB_VFS_NEXT_FS_CAPABILITIES(handle, p_ts_res) | FILE_NAMED_STREAMS;
 844 }
 845
 846 static ssize_t streams_xattr_pwrite(vfs_handle_struct *handle,
 847                                     files_struct *fsp, const void *data,
 848                                     size_t n, off_t offset)
 849 {
 850         struct stream_io *sio =
 851                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
 852         struct ea_struct ea;
 853         NTSTATUS status;
 854         int ret;
 855
 856         DEBUG(10, ("streams_xattr_pwrite called for %d bytes\n", (int)n));
 857
 858         if (sio == NULL) {
 859                 return SMB_VFS_NEXT_PWRITE(handle, fsp, data, n, offset);
 860         }
 861
 862         if (!streams_xattr_recheck(sio)) {
 863                 return -1;
 864         }
 865
 866         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
 867                               sio->base, sio->xattr_name, &ea);
 868         if (!NT_STATUS_IS_OK(status)) {
 869                 return -1;
 870         }
 871
 872         if ((offset + n) > ea.value.length-1) {
 873                 uint8 *tmp;
 874
 875                 tmp = talloc_realloc(talloc_tos(), ea.value.data, uint8,
 876                                            offset + n + 1);
 877
 878                 if (tmp == NULL) {
 879                         TALLOC_FREE(ea.value.data);
 880                         errno = ENOMEM;
 881                         return -1;
 882                 }
 883                 ea.value.data = tmp;
 884                 ea.value.length = offset + n + 1;
 885                 ea.value.data[offset+n] = 0;
 886         }
 887
 888         memcpy(ea.value.data + offset, data, n);
 889
 890         if (fsp->base_fsp->fh->fd != -1) {
 891                 ret = SMB_VFS_FSETXATTR(fsp->base_fsp,
 892                                 sio->xattr_name,
 893                                 ea.value.data, ea.value.length, 0);
 894         } else {
 895                 ret = SMB_VFS_SETXATTR(fsp->conn,
 896                                        fsp->base_fsp->fsp_name->base_name,
 897                                 sio->xattr_name,
 898                                 ea.value.data, ea.value.length, 0);
 899         }
 900         TALLOC_FREE(ea.value.data);
 901
 902         if (ret == -1) {
 903                 return -1;
 904         }
 905
 906         return n;
 907 }
 908
 909 static ssize_t streams_xattr_pread(vfs_handle_struct *handle,
 910                                    files_struct *fsp, void *data,
 911                                    size_t n, off_t offset)
 912 {
 913         struct stream_io *sio =
 914                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
 915         struct ea_struct ea;
 916         NTSTATUS status;
 917         size_t length, overlap;
 918
 919         DEBUG(10, ("streams_xattr_pread: offset=%d, size=%d\n",
 920                    (int)offset, (int)n));
 921
 922         if (sio == NULL) {
 923                 return SMB_VFS_NEXT_PREAD(handle, fsp, data, n, offset);
 924         }
 925
 926         if (!streams_xattr_recheck(sio)) {
 927                 return -1;
 928         }
 929
 930         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
 931                               sio->base, sio->xattr_name, &ea);
 932         if (!NT_STATUS_IS_OK(status)) {
 933                 return -1;
 934         }
 935
 936         length = ea.value.length-1;
 937
 938         DEBUG(10, ("streams_xattr_pread: get_ea_value returned %d bytes\n",
 939                    (int)length));
 940
 941         /* Attempt to read past EOF. */
 942         if (length <= offset) {
 943                 return 0;
 944         }
 945
 946         overlap = (offset + n) > length ? (length - offset) : n;
 947         memcpy(data, ea.value.data + offset, overlap);
 948
 949         TALLOC_FREE(ea.value.data);
 950         return overlap;
 951 }
 952
 953 static int streams_xattr_ftruncate(struct vfs_handle_struct *handle,
 954                                         struct files_struct *fsp,
 955                                         off_t offset)
 956 {
 957         int ret;
 958         uint8 *tmp;
 959         struct ea_struct ea;
 960         NTSTATUS status;
 961         struct stream_io *sio =
 962                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
 963
 964         DEBUG(10, ("streams_xattr_ftruncate called for file %s offset %.0f\n",
 965                    fsp_str_dbg(fsp), (double)offset));
 966
 967         if (sio == NULL) {
 968                 return SMB_VFS_NEXT_FTRUNCATE(handle, fsp, offset);
 969         }
 970
 971         if (!streams_xattr_recheck(sio)) {
 972                 return -1;
 973         }
 974
 975         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
 976                               sio->base, sio->xattr_name, &ea);
 977         if (!NT_STATUS_IS_OK(status)) {
 978                 return -1;
 979         }
 980
 981         tmp = talloc_realloc(talloc_tos(), ea.value.data, uint8,
 982                                    offset + 1);
 983
 984         if (tmp == NULL) {
 985                 TALLOC_FREE(ea.value.data);
 986                 errno = ENOMEM;
 987                 return -1;
 988         }
 989
 990         /* Did we expand ? */
 991         if (ea.value.length < offset + 1) {
 992                 memset(&tmp[ea.value.length], '\0',
 993                         offset + 1 - ea.value.length);
 994         }
 995
 996         ea.value.data = tmp;
 997         ea.value.length = offset + 1;
 998         ea.value.data[offset] = 0;
 999
1000         if (fsp->base_fsp->fh->fd != -1) {
1001                 ret = SMB_VFS_FSETXATTR(fsp->base_fsp,
1002                                 sio->xattr_name,
1003                                 ea.value.data, ea.value.length, 0);
1004         } else {
1005                 ret = SMB_VFS_SETXATTR(fsp->conn,
1006                                        fsp->base_fsp->fsp_name->base_name,
1007                                 sio->xattr_name,
1008                                 ea.value.data, ea.value.length, 0);
1009         }
1010
1011         TALLOC_FREE(ea.value.data);
1012
1013         if (ret == -1) {
1014                 return -1;
1015         }
1016
1017         return 0;
1018 }
1019
1020 static int streams_xattr_fallocate(struct vfs_handle_struct *handle,
1021                                         struct files_struct *fsp,
1022                                         enum vfs_fallocate_mode mode,
1023                                         off_t offset,
1024                                         off_t len)
1025 {
1026         struct stream_io *sio =
1027                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
1028
1029         DEBUG(10, ("streams_xattr_fallocate called for file %s offset %.0f"
1030                 "len = %.0f\n",
1031                 fsp_str_dbg(fsp), (double)offset, (double)len));
1032
1033         if (sio == NULL) {
1034                 return SMB_VFS_NEXT_FALLOCATE(handle, fsp, mode, offset, len);
1035         }
1036
1037         if (!streams_xattr_recheck(sio)) {
1038                 return errno;
1039         }
1040
1041         /* Let the pwrite code path handle it. */
1042         return ENOSYS;
1043 }
1044
1045
1046 static struct vfs_fn_pointers vfs_streams_xattr_fns = {
1047         .fs_capabilities_fn = streams_xattr_fs_capabilities,
1048         .open_fn = streams_xattr_open,
1049         .stat_fn = streams_xattr_stat,
1050         .fstat_fn = streams_xattr_fstat,
1051         .lstat_fn = streams_xattr_lstat,
1052         .pread_fn = streams_xattr_pread,
1053         .pwrite_fn = streams_xattr_pwrite,
1054         .unlink_fn = streams_xattr_unlink,
1055         .rename_fn = streams_xattr_rename,
1056         .ftruncate_fn = streams_xattr_ftruncate,
1057         .fallocate_fn = streams_xattr_fallocate,
1058         .streaminfo_fn = streams_xattr_streaminfo,
1059 };
1060
1061 NTSTATUS vfs_streams_xattr_init(void);
1062 NTSTATUS vfs_streams_xattr_init(void)
1063 {
1064         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "streams_xattr",
1065                                 &vfs_streams_xattr_fns);
1066 }