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