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 streams_xattr_config {
  33         const char *prefix;
  34         size_t prefix_len;
  35         bool store_stream_type;
  36 };
  37
  38 struct stream_io {
  39         char *base;
  40         char *xattr_name;
  41         void *fsp_name_ptr;
  42         files_struct *fsp;
  43         vfs_handle_struct *handle;
  44 };
  45
  46 static SMB_INO_T stream_inode(const SMB_STRUCT_STAT *sbuf, const char *sname)
  47 {
  48         MD5_CTX ctx;
  49         unsigned char hash[16];
  50         SMB_INO_T result;
  51         char *upper_sname;
  52
  53         DEBUG(10, ("stream_inode called for %lu/%lu [%s]\n",
  54                    (unsigned long)sbuf->st_ex_dev,
  55                    (unsigned long)sbuf->st_ex_ino, sname));
  56
  57         upper_sname = talloc_strdup_upper(talloc_tos(), sname);
  58         SMB_ASSERT(upper_sname != NULL);
  59
  60         MD5Init(&ctx);
  61         MD5Update(&ctx, (const unsigned char *)&(sbuf->st_ex_dev),
  62                   sizeof(sbuf->st_ex_dev));
  63         MD5Update(&ctx, (const unsigned char *)&(sbuf->st_ex_ino),
  64                   sizeof(sbuf->st_ex_ino));
  65         MD5Update(&ctx, (unsigned char *)upper_sname,
  66                   talloc_get_size(upper_sname)-1);
  67         MD5Final(hash, &ctx);
  68
  69         TALLOC_FREE(upper_sname);
  70
  71         /* Hopefully all the variation is in the lower 4 (or 8) bytes! */
  72         memcpy(&result, hash, sizeof(result));
  73
  74         DEBUG(10, ("stream_inode returns %lu\n", (unsigned long)result));
  75
  76         return result;
  77 }
  78
  79 static ssize_t get_xattr_size(connection_struct *conn,
  80                                 files_struct *fsp,
  81                                 const char *fname,
  82                                 const char *xattr_name)
  83 {
  84         NTSTATUS status;
  85         struct ea_struct ea;
  86         ssize_t result;
  87
  88         status = get_ea_value(talloc_tos(), conn, fsp, fname,
  89                               xattr_name, &ea);
  90
  91         if (!NT_STATUS_IS_OK(status)) {
  92                 return -1;
  93         }
  94
  95         result = ea.value.length-1;
  96         TALLOC_FREE(ea.value.data);
  97         return result;
  98 }
  99
 100 /**
 101  * Given a stream name, populate xattr_name with the xattr name to use for
 102  * accessing the stream.
 103  */
 104 static NTSTATUS streams_xattr_get_name(vfs_handle_struct *handle,
 105                                        TALLOC_CTX *ctx,
 106                                        const char *stream_name,
 107                                        char **xattr_name)
 108 {
 109         char *stype;
 110         struct streams_xattr_config *config;
 111
 112         SMB_VFS_HANDLE_GET_DATA(handle, config, struct streams_xattr_config,
 113                                 return NT_STATUS_UNSUCCESSFUL);
 114
 115         stype = strchr_m(stream_name + 1, ':');
 116
 117         if (stype) {
 118                 if (strcasecmp_m(stype, ":$DATA") != 0) {
 119                         return NT_STATUS_INVALID_PARAMETER;
 120                 }
 121         }
 122
 123         *xattr_name = talloc_asprintf(ctx, "%s%s",
 124                                       config->prefix,
 125                                       stream_name + 1);
 126         if (*xattr_name == NULL) {
 127                 return NT_STATUS_NO_MEMORY;
 128         }
 129
 130         if (stype != NULL) {
 131                 /* Normalize the stream type to upercase. */
 132                 if (!strupper_m(strrchr_m(*xattr_name, ':') + 1)) {
 133                         return NT_STATUS_INVALID_PARAMETER;
 134                 }
 135         } else if (config->store_stream_type) {
 136                 /*
 137                  * Append an explicit stream type if one wasn't
 138                  * specified.
 139                  */
 140                 *xattr_name = talloc_asprintf(ctx, "%s%s",
 141                                               *xattr_name, ":$DATA");
 142                 if (*xattr_name == NULL) {
 143                         return NT_STATUS_NO_MEMORY;
 144                 }
 145         }
 146
 147         DEBUG(10, ("xattr_name: %s, stream_name: %s\n", *xattr_name,
 148                    stream_name));
 149
 150         return NT_STATUS_OK;
 151 }
 152
 153 static bool streams_xattr_recheck(struct stream_io *sio)
 154 {
 155         NTSTATUS status;
 156         char *xattr_name = NULL;
 157
 158         if (sio->fsp->fsp_name == sio->fsp_name_ptr) {
 159                 return true;
 160         }
 161
 162         if (sio->fsp->fsp_name->stream_name == NULL) {
 163                 /* how can this happen */
 164                 errno = EINVAL;
 165                 return false;
 166         }
 167
 168         status = streams_xattr_get_name(sio->handle, talloc_tos(),
 169                                         sio->fsp->fsp_name->stream_name,
 170                                         &xattr_name);
 171         if (!NT_STATUS_IS_OK(status)) {
 172                 return false;
 173         }
 174
 175         TALLOC_FREE(sio->xattr_name);
 176         TALLOC_FREE(sio->base);
 177         sio->xattr_name = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(sio->handle, sio->fsp),
 178                                         xattr_name);
 179         sio->base = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(sio->handle, sio->fsp),
 180                                   sio->fsp->fsp_name->base_name);
 181         sio->fsp_name_ptr = sio->fsp->fsp_name;
 182
 183         TALLOC_FREE(xattr_name);
 184
 185         if ((sio->xattr_name == NULL) || (sio->base == NULL)) {
 186                 return false;
 187         }
 188
 189         return true;
 190 }
 191
 192 /**
 193  * Helper to stat/lstat the base file of an smb_fname.
 194  */
 195 static int streams_xattr_stat_base(vfs_handle_struct *handle,
 196                                    struct smb_filename *smb_fname,
 197                                    bool follow_links)
 198 {
 199         char *tmp_stream_name;
 200         int result;
 201
 202         tmp_stream_name = smb_fname->stream_name;
 203         smb_fname->stream_name = NULL;
 204         if (follow_links) {
 205                 result = SMB_VFS_NEXT_STAT(handle, smb_fname);
 206         } else {
 207                 result = SMB_VFS_NEXT_LSTAT(handle, smb_fname);
 208         }
 209         smb_fname->stream_name = tmp_stream_name;
 210         return result;
 211 }
 212
 213 static int streams_xattr_fstat(vfs_handle_struct *handle, files_struct *fsp,
 214                                SMB_STRUCT_STAT *sbuf)
 215 {
 216         struct smb_filename *smb_fname_base = NULL;
 217         int ret = -1;
 218         struct stream_io *io = (struct stream_io *)
 219                 VFS_FETCH_FSP_EXTENSION(handle, fsp);
 220
 221         DEBUG(10, ("streams_xattr_fstat called for %d\n", fsp->fh->fd));
 222
 223         if (io == NULL || fsp->base_fsp == NULL) {
 224                 return SMB_VFS_NEXT_FSTAT(handle, fsp, sbuf);
 225         }
 226
 227         if (!streams_xattr_recheck(io)) {
 228                 return -1;
 229         }
 230
 231         /* Create an smb_filename with stream_name == NULL. */
 232         smb_fname_base = synthetic_smb_fname(talloc_tos(), io->base,
 233                                              NULL, NULL);
 234         if (smb_fname_base == NULL) {
 235                 errno = ENOMEM;
 236                 return -1;
 237         }
 238
 239         if (lp_posix_pathnames()) {
 240                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_base);
 241         } else {
 242                 ret = SMB_VFS_STAT(handle->conn, smb_fname_base);
 243         }
 244         *sbuf = smb_fname_base->st;
 245         TALLOC_FREE(smb_fname_base);
 246
 247         if (ret == -1) {
 248                 return -1;
 249         }
 250
 251         sbuf->st_ex_size = get_xattr_size(handle->conn, fsp->base_fsp,
 252                                         io->base, io->xattr_name);
 253         if (sbuf->st_ex_size == -1) {
 254                 return -1;
 255         }
 256
 257         DEBUG(10, ("sbuf->st_ex_size = %d\n", (int)sbuf->st_ex_size));
 258
 259         sbuf->st_ex_ino = stream_inode(sbuf, io->xattr_name);
 260         sbuf->st_ex_mode &= ~S_IFMT;
 261         sbuf->st_ex_mode |= S_IFREG;
 262         sbuf->st_ex_blocks = sbuf->st_ex_size / STAT_ST_BLOCKSIZE + 1;
 263
 264         return 0;
 265 }
 266
 267 static int streams_xattr_stat(vfs_handle_struct *handle,
 268                               struct smb_filename *smb_fname)
 269 {
 270         NTSTATUS status;
 271         int result = -1;
 272         char *xattr_name = NULL;
 273
 274         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 275                 return SMB_VFS_NEXT_STAT(handle, smb_fname);
 276         }
 277
 278         /* Note if lp_posix_paths() is true, we can never
 279          * get here as is_ntfs_stream_smb_fname() is
 280          * always false. So we never need worry about
 281          * not following links here. */
 282
 283         /* If the default stream is requested, just stat the base file. */
 284         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 285                 return streams_xattr_stat_base(handle, smb_fname, true);
 286         }
 287
 288         /* Populate the stat struct with info from the base file. */
 289         if (streams_xattr_stat_base(handle, smb_fname, true) == -1) {
 290                 return -1;
 291         }
 292
 293         /* Derive the xattr name to lookup. */
 294         status = streams_xattr_get_name(handle, talloc_tos(),
 295                                         smb_fname->stream_name, &xattr_name);
 296         if (!NT_STATUS_IS_OK(status)) {
 297                 errno = map_errno_from_nt_status(status);
 298                 return -1;
 299         }
 300
 301         /* Augment the base file's stat information before returning. */
 302         smb_fname->st.st_ex_size = get_xattr_size(handle->conn, NULL,
 303                                                   smb_fname->base_name,
 304                                                   xattr_name);
 305         if (smb_fname->st.st_ex_size == -1) {
 306                 errno = ENOENT;
 307                 result = -1;
 308                 goto fail;
 309         }
 310
 311         smb_fname->st.st_ex_ino = stream_inode(&smb_fname->st, xattr_name);
 312         smb_fname->st.st_ex_mode &= ~S_IFMT;
 313         smb_fname->st.st_ex_mode |= S_IFREG;
 314         smb_fname->st.st_ex_blocks =
 315             smb_fname->st.st_ex_size / STAT_ST_BLOCKSIZE + 1;
 316
 317         result = 0;
 318  fail:
 319         TALLOC_FREE(xattr_name);
 320         return result;
 321 }
 322
 323 static int streams_xattr_lstat(vfs_handle_struct *handle,
 324                                struct smb_filename *smb_fname)
 325 {
 326         NTSTATUS status;
 327         int result = -1;
 328         char *xattr_name = NULL;
 329
 330         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 331                 return SMB_VFS_NEXT_LSTAT(handle, smb_fname);
 332         }
 333
 334         /* If the default stream is requested, just stat the base file. */
 335         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 336                 return streams_xattr_stat_base(handle, smb_fname, false);
 337         }
 338
 339         /* Populate the stat struct with info from the base file. */
 340         if (streams_xattr_stat_base(handle, smb_fname, false) == -1) {
 341                 return -1;
 342         }
 343
 344         /* Derive the xattr name to lookup. */
 345         status = streams_xattr_get_name(handle, talloc_tos(),
 346                                         smb_fname->stream_name, &xattr_name);
 347         if (!NT_STATUS_IS_OK(status)) {
 348                 errno = map_errno_from_nt_status(status);
 349                 return -1;
 350         }
 351
 352         /* Augment the base file's stat information before returning. */
 353         smb_fname->st.st_ex_size = get_xattr_size(handle->conn, NULL,
 354                                                   smb_fname->base_name,
 355                                                   xattr_name);
 356         if (smb_fname->st.st_ex_size == -1) {
 357                 errno = ENOENT;
 358                 result = -1;
 359                 goto fail;
 360         }
 361
 362         smb_fname->st.st_ex_ino = stream_inode(&smb_fname->st, xattr_name);
 363         smb_fname->st.st_ex_mode &= ~S_IFMT;
 364         smb_fname->st.st_ex_mode |= S_IFREG;
 365         smb_fname->st.st_ex_blocks =
 366             smb_fname->st.st_ex_size / STAT_ST_BLOCKSIZE + 1;
 367
 368         result = 0;
 369
 370  fail:
 371         TALLOC_FREE(xattr_name);
 372         return result;
 373 }
 374
 375 static int streams_xattr_open(vfs_handle_struct *handle,
 376                               struct smb_filename *smb_fname,
 377                               files_struct *fsp, int flags, mode_t mode)
 378 {
 379         NTSTATUS status;
 380         struct smb_filename *smb_fname_base = NULL;
 381         struct stream_io *sio;
 382         struct ea_struct ea;
 383         char *xattr_name = NULL;
 384         int baseflags;
 385         int hostfd = -1;
 386
 387         DEBUG(10, ("streams_xattr_open called for %s with flags 0x%x\n",
 388                    smb_fname_str_dbg(smb_fname), flags));
 389
 390         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 391                 return SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
 392         }
 393
 394         /* If the default stream is requested, just open the base file. */
 395         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 396                 char *tmp_stream_name;
 397                 int ret;
 398
 399                 tmp_stream_name = smb_fname->stream_name;
 400                 smb_fname->stream_name = NULL;
 401
 402                 ret = SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
 403
 404                 smb_fname->stream_name = tmp_stream_name;
 405
 406                 return ret;
 407         }
 408
 409         status = streams_xattr_get_name(handle, talloc_tos(),
 410                                         smb_fname->stream_name, &xattr_name);
 411         if (!NT_STATUS_IS_OK(status)) {
 412                 errno = map_errno_from_nt_status(status);
 413                 goto fail;
 414         }
 415
 416         /* Create an smb_filename with stream_name == NULL. */
 417         smb_fname_base = synthetic_smb_fname(
 418                 talloc_tos(), smb_fname->base_name, NULL, NULL);
 419         if (smb_fname_base == NULL) {
 420                 errno = ENOMEM;
 421                 goto fail;
 422         }
 423
 424         /*
 425          * We use baseflags to turn off nasty side-effects when opening the
 426          * underlying file.
 427          */
 428         baseflags = flags;
 429         baseflags &= ~O_TRUNC;
 430         baseflags &= ~O_EXCL;
 431         baseflags &= ~O_CREAT;
 432
 433         hostfd = SMB_VFS_OPEN(handle->conn, smb_fname_base, fsp,
 434                               baseflags, mode);
 435
 436         TALLOC_FREE(smb_fname_base);
 437
 438         /* It is legit to open a stream on a directory, but the base
 439          * fd has to be read-only.
 440          */
 441         if ((hostfd == -1) && (errno == EISDIR)) {
 442                 baseflags &= ~O_ACCMODE;
 443                 baseflags |= O_RDONLY;
 444                 hostfd = SMB_VFS_OPEN(handle->conn, smb_fname, fsp, baseflags,
 445                                       mode);
 446         }
 447
 448         if (hostfd == -1) {
 449                 goto fail;
 450         }
 451
 452         status = get_ea_value(talloc_tos(), handle->conn, NULL,
 453                               smb_fname->base_name, xattr_name, &ea);
 454
 455         DEBUG(10, ("get_ea_value returned %s\n", nt_errstr(status)));
 456
 457         if (!NT_STATUS_IS_OK(status)
 458             && !NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND)) {
 459                 /*
 460                  * The base file is not there. This is an error even if we got
 461                  * O_CREAT, the higher levels should have created the base
 462                  * file for us.
 463                  */
 464                 DEBUG(10, ("streams_xattr_open: base file %s not around, "
 465                            "returning ENOENT\n", smb_fname->base_name));
 466                 errno = ENOENT;
 467                 goto fail;
 468         }
 469
 470         if ((!NT_STATUS_IS_OK(status) && (flags & O_CREAT)) ||
 471             (flags & O_TRUNC)) {
 472                 /*
 473                  * The attribute does not exist or needs to be truncated
 474                  */
 475
 476                 /*
 477                  * Darn, xattrs need at least 1 byte
 478                  */
 479                 char null = '\0';
 480
 481                 DEBUG(10, ("creating or truncating attribute %s on file %s\n",
 482                            xattr_name, smb_fname->base_name));
 483
 484                 if (fsp->base_fsp->fh->fd != -1) {
 485                         if (SMB_VFS_FSETXATTR(
 486                                         fsp->base_fsp, xattr_name,
 487                                         &null, sizeof(null),
 488                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 489                                 goto fail;
 490                         }
 491                 } else {
 492                         if (SMB_VFS_SETXATTR(
 493                                         handle->conn, smb_fname->base_name,
 494                                         xattr_name, &null, sizeof(null),
 495                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 496                                 goto fail;
 497                         }
 498                 }
 499         }
 500
 501         sio = (struct stream_io *)VFS_ADD_FSP_EXTENSION(handle, fsp,
 502                                                         struct stream_io,
 503                                                         NULL);
 504         if (sio == NULL) {
 505                 errno = ENOMEM;
 506                 goto fail;
 507         }
 508
 509         sio->xattr_name = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(handle, fsp),
 510                                         xattr_name);
 511         sio->base = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(handle, fsp),
 512                                   smb_fname->base_name);
 513         sio->fsp_name_ptr = fsp->fsp_name;
 514         sio->handle = handle;
 515         sio->fsp = fsp;
 516
 517         if ((sio->xattr_name == NULL) || (sio->base == NULL)) {
 518                 errno = ENOMEM;
 519                 goto fail;
 520         }
 521
 522         return hostfd;
 523
 524  fail:
 525         if (hostfd >= 0) {
 526                 /*
 527                  * BUGBUGBUG -- we would need to call fd_close_posix here, but
 528                  * we don't have a full fsp yet
 529                  */
 530                 fsp->fh->fd = hostfd;
 531                 SMB_VFS_CLOSE(fsp);
 532         }
 533
 534         return -1;
 535 }
 536
 537 static int streams_xattr_unlink(vfs_handle_struct *handle,
 538                                 const struct smb_filename *smb_fname)
 539 {
 540         NTSTATUS status;
 541         int ret = -1;
 542         char *xattr_name = NULL;
 543
 544         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 545                 return SMB_VFS_NEXT_UNLINK(handle, smb_fname);
 546         }
 547
 548         /* If the default stream is requested, just open the base file. */
 549         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 550                 struct smb_filename *smb_fname_base = NULL;
 551
 552                 smb_fname_base = cp_smb_filename(talloc_tos(), smb_fname);
 553                 if (smb_fname_base == NULL) {
 554                         errno = ENOMEM;
 555                         return -1;
 556                 }
 557
 558                 ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname_base);
 559
 560                 TALLOC_FREE(smb_fname_base);
 561                 return ret;
 562         }
 563
 564         status = streams_xattr_get_name(handle, talloc_tos(),
 565                                         smb_fname->stream_name, &xattr_name);
 566         if (!NT_STATUS_IS_OK(status)) {
 567                 errno = map_errno_from_nt_status(status);
 568                 goto fail;
 569         }
 570
 571         ret = SMB_VFS_REMOVEXATTR(handle->conn, smb_fname->base_name, xattr_name);
 572
 573         if ((ret == -1) && (errno == ENOATTR)) {
 574                 errno = ENOENT;
 575                 goto fail;
 576         }
 577
 578         ret = 0;
 579
 580  fail:
 581         TALLOC_FREE(xattr_name);
 582         return ret;
 583 }
 584
 585 static int streams_xattr_rename(vfs_handle_struct *handle,
 586                                 const struct smb_filename *smb_fname_src,
 587                                 const struct smb_filename *smb_fname_dst)
 588 {
 589         NTSTATUS status;
 590         int ret = -1;
 591         char *src_xattr_name = NULL;
 592         char *dst_xattr_name = NULL;
 593         bool src_is_stream, dst_is_stream;
 594         ssize_t oret;
 595         ssize_t nret;
 596         struct ea_struct ea;
 597
 598         src_is_stream = is_ntfs_stream_smb_fname(smb_fname_src);
 599         dst_is_stream = is_ntfs_stream_smb_fname(smb_fname_dst);
 600
 601         if (!src_is_stream && !dst_is_stream) {
 602                 return SMB_VFS_NEXT_RENAME(handle, smb_fname_src,
 603                                            smb_fname_dst);
 604         }
 605
 606         /* For now don't allow renames from or to the default stream. */
 607         if (is_ntfs_default_stream_smb_fname(smb_fname_src) ||
 608             is_ntfs_default_stream_smb_fname(smb_fname_dst)) {
 609                 errno = ENOSYS;
 610                 goto done;
 611         }
 612
 613         /* Don't rename if the streams are identical. */
 614         if (strcasecmp_m(smb_fname_src->stream_name,
 615                        smb_fname_dst->stream_name) == 0) {
 616                 goto done;
 617         }
 618
 619         /* Get the xattr names. */
 620         status = streams_xattr_get_name(handle, talloc_tos(),
 621                                         smb_fname_src->stream_name,
 622                                         &src_xattr_name);
 623         if (!NT_STATUS_IS_OK(status)) {
 624                 errno = map_errno_from_nt_status(status);
 625                 goto fail;
 626         }
 627         status = streams_xattr_get_name(handle, talloc_tos(),
 628                                         smb_fname_dst->stream_name,
 629                                         &dst_xattr_name);
 630         if (!NT_STATUS_IS_OK(status)) {
 631                 errno = map_errno_from_nt_status(status);
 632                 goto fail;
 633         }
 634
 635         /* read the old stream */
 636         status = get_ea_value(talloc_tos(), handle->conn, NULL,
 637                               smb_fname_src->base_name, src_xattr_name, &ea);
 638         if (!NT_STATUS_IS_OK(status)) {
 639                 errno = ENOENT;
 640                 goto fail;
 641         }
 642
 643         /* (over)write the new stream */
 644         nret = SMB_VFS_SETXATTR(handle->conn, smb_fname_src->base_name,
 645                                 dst_xattr_name, ea.value.data, ea.value.length,
 646                                 0);
 647         if (nret < 0) {
 648                 if (errno == ENOATTR) {
 649                         errno = ENOENT;
 650                 }
 651                 goto fail;
 652         }
 653
 654         /* remove the old stream */
 655         oret = SMB_VFS_REMOVEXATTR(handle->conn, smb_fname_src->base_name,
 656                                    src_xattr_name);
 657         if (oret < 0) {
 658                 if (errno == ENOATTR) {
 659                         errno = ENOENT;
 660                 }
 661                 goto fail;
 662         }
 663
 664  done:
 665         errno = 0;
 666         ret = 0;
 667  fail:
 668         TALLOC_FREE(src_xattr_name);
 669         TALLOC_FREE(dst_xattr_name);
 670         return ret;
 671 }
 672
 673 static NTSTATUS walk_xattr_streams(vfs_handle_struct *handle, files_struct *fsp,
 674                                    const char *fname,
 675                                    bool (*fn)(struct ea_struct *ea,
 676                                               void *private_data),
 677                                    void *private_data)
 678 {
 679         NTSTATUS status;
 680         char **names;
 681         size_t i, num_names;
 682         struct streams_xattr_config *config;
 683
 684         SMB_VFS_HANDLE_GET_DATA(handle, config, struct streams_xattr_config,
 685                                 return NT_STATUS_UNSUCCESSFUL);
 686
 687         status = get_ea_names_from_file(talloc_tos(), handle->conn, fsp, fname,
 688                                         &names, &num_names);
 689         if (!NT_STATUS_IS_OK(status)) {
 690                 return status;
 691         }
 692
 693         for (i=0; i<num_names; i++) {
 694                 struct ea_struct ea;
 695
 696                 /*
 697                  * We want to check with samba_private_attr_name()
 698                  * whether the xattr name is a private one,
 699                  * unfortunately it flags xattrs that begin with the
 700                  * default streams prefix as private.
 701                  *
 702                  * By only calling samba_private_attr_name() in case
 703                  * the xattr does NOT begin with the default prefix,
 704                  * we know that if it returns 'true' it definitely one
 705                  * of our internal xattr like "user.DOSATTRIB".
 706                  */
 707                 if (strncasecmp_m(names[i], SAMBA_XATTR_DOSSTREAM_PREFIX,
 708                                   strlen(SAMBA_XATTR_DOSSTREAM_PREFIX)) != 0) {
 709                         if (samba_private_attr_name(names[i])) {
 710                                 continue;
 711                         }
 712                 }
 713
 714                 if (strncmp(names[i], config->prefix,
 715                             config->prefix_len) != 0) {
 716                         continue;
 717                 }
 718
 719                 status = get_ea_value(names, handle->conn, fsp, fname,
 720                                       names[i], &ea);
 721                 if (!NT_STATUS_IS_OK(status)) {
 722                         DEBUG(10, ("Could not get ea %s for file %s: %s\n",
 723                                    names[i], fname, nt_errstr(status)));
 724                         continue;
 725                 }
 726
 727                 ea.name = talloc_asprintf(
 728                         ea.value.data, ":%s%s",
 729                         names[i] + config->prefix_len,
 730                         config->store_stream_type ? "" : ":$DATA");
 731                 if (ea.name == NULL) {
 732                         DEBUG(0, ("talloc failed\n"));
 733                         continue;
 734                 }
 735
 736                 if (!fn(&ea, private_data)) {
 737                         TALLOC_FREE(ea.value.data);
 738                         return NT_STATUS_OK;
 739                 }
 740
 741                 TALLOC_FREE(ea.value.data);
 742         }
 743
 744         TALLOC_FREE(names);
 745         return NT_STATUS_OK;
 746 }
 747
 748 static bool add_one_stream(TALLOC_CTX *mem_ctx, unsigned int *num_streams,
 749                            struct stream_struct **streams,
 750                            const char *name, off_t size,
 751                            off_t alloc_size)
 752 {
 753         struct stream_struct *tmp;
 754
 755         tmp = talloc_realloc(mem_ctx, *streams, struct stream_struct,
 756                                    (*num_streams)+1);
 757         if (tmp == NULL) {
 758                 return false;
 759         }
 760
 761         tmp[*num_streams].name = talloc_strdup(tmp, name);
 762         if (tmp[*num_streams].name == NULL) {
 763                 return false;
 764         }
 765
 766         tmp[*num_streams].size = size;
 767         tmp[*num_streams].alloc_size = alloc_size;
 768
 769         *streams = tmp;
 770         *num_streams += 1;
 771         return true;
 772 }
 773
 774 struct streaminfo_state {
 775         TALLOC_CTX *mem_ctx;
 776         vfs_handle_struct *handle;
 777         unsigned int num_streams;
 778         struct stream_struct *streams;
 779         NTSTATUS status;
 780 };
 781
 782 static bool collect_one_stream(struct ea_struct *ea, void *private_data)
 783 {
 784         struct streaminfo_state *state =
 785                 (struct streaminfo_state *)private_data;
 786
 787         if (!add_one_stream(state->mem_ctx,
 788                             &state->num_streams, &state->streams,
 789                             ea->name, ea->value.length-1,
 790                             smb_roundup(state->handle->conn,
 791                                         ea->value.length-1))) {
 792                 state->status = NT_STATUS_NO_MEMORY;
 793                 return false;
 794         }
 795
 796         return true;
 797 }
 798
 799 static NTSTATUS streams_xattr_streaminfo(vfs_handle_struct *handle,
 800                                          struct files_struct *fsp,
 801                                          const char *fname,
 802                                          TALLOC_CTX *mem_ctx,
 803                                          unsigned int *pnum_streams,
 804                                          struct stream_struct **pstreams)
 805 {
 806         SMB_STRUCT_STAT sbuf;
 807         int ret;
 808         NTSTATUS status;
 809         struct streaminfo_state state;
 810
 811         if ((fsp != NULL) && (fsp->fh->fd != -1)) {
 812                 ret = SMB_VFS_FSTAT(fsp, &sbuf);
 813         }
 814         else {
 815                 struct smb_filename *smb_fname = NULL;
 816                 smb_fname = synthetic_smb_fname(talloc_tos(), fname, NULL,
 817                                                 NULL);
 818                 if (smb_fname == NULL) {
 819                         return NT_STATUS_NO_MEMORY;
 820                 }
 821                 if (lp_posix_pathnames()) {
 822                         ret = SMB_VFS_LSTAT(handle->conn, smb_fname);
 823                 } else {
 824                         ret = SMB_VFS_STAT(handle->conn, smb_fname);
 825                 }
 826                 sbuf = smb_fname->st;
 827                 TALLOC_FREE(smb_fname);
 828         }
 829
 830         if (ret == -1) {
 831                 return map_nt_error_from_unix(errno);
 832         }
 833
 834         state.streams = *pstreams;
 835         state.num_streams = *pnum_streams;
 836         state.mem_ctx = mem_ctx;
 837         state.handle = handle;
 838         state.status = NT_STATUS_OK;
 839
 840         if (S_ISLNK(sbuf.st_ex_mode)) {
 841                 /*
 842                  * Currently we do't have SMB_VFS_LLISTXATTR
 843                  * inside the VFS which means there's no way
 844                  * to cope with a symlink when lp_posix_pathnames().
 845                  * returns true. For now ignore links.
 846                  * FIXME - by adding SMB_VFS_LLISTXATTR. JRA.
 847                  */
 848                 status = NT_STATUS_OK;
 849         } else {
 850                 status = walk_xattr_streams(handle, fsp, fname,
 851                                     collect_one_stream, &state);
 852         }
 853
 854         if (!NT_STATUS_IS_OK(status)) {
 855                 TALLOC_FREE(state.streams);
 856                 return status;
 857         }
 858
 859         if (!NT_STATUS_IS_OK(state.status)) {
 860                 TALLOC_FREE(state.streams);
 861                 return state.status;
 862         }
 863
 864         *pnum_streams = state.num_streams;
 865         *pstreams = state.streams;
 866
 867         return SMB_VFS_NEXT_STREAMINFO(handle, fsp, fname, mem_ctx, pnum_streams, pstreams);
 868 }
 869
 870 static uint32_t streams_xattr_fs_capabilities(struct vfs_handle_struct *handle,
 871                         enum timestamp_set_resolution *p_ts_res)
 872 {
 873         return SMB_VFS_NEXT_FS_CAPABILITIES(handle, p_ts_res) | FILE_NAMED_STREAMS;
 874 }
 875
 876 static int streams_xattr_connect(vfs_handle_struct *handle,
 877                                  const char *service, const char *user)
 878 {
 879         struct streams_xattr_config *config;
 880         const char *default_prefix = SAMBA_XATTR_DOSSTREAM_PREFIX;
 881         const char *prefix;
 882         int rc;
 883
 884         rc = SMB_VFS_NEXT_CONNECT(handle, service, user);
 885         if (rc != 0) {
 886                 return rc;
 887         }
 888
 889         config = talloc_zero(handle->conn, struct streams_xattr_config);
 890         if (config == NULL) {
 891                 DEBUG(1, ("talloc_zero() failed\n"));
 892                 errno = ENOMEM;
 893                 return -1;
 894         }
 895
 896         prefix = lp_parm_const_string(SNUM(handle->conn),
 897                                       "streams_xattr", "prefix",
 898                                       default_prefix);
 899         config->prefix = talloc_strdup(config, prefix);
 900         if (config->prefix == NULL) {
 901                 DEBUG(1, ("talloc_strdup() failed\n"));
 902                 errno = ENOMEM;
 903                 return -1;
 904         }
 905         config->prefix_len = strlen(config->prefix);
 906         DEBUG(10, ("streams_xattr using stream prefix: %s\n", config->prefix));
 907
 908         config->store_stream_type = lp_parm_bool(SNUM(handle->conn),
 909                                                  "streams_xattr",
 910                                                  "store_stream_type",
 911                                                  true);
 912
 913         SMB_VFS_HANDLE_SET_DATA(handle, config,
 914                                 NULL, struct stream_xattr_config,
 915                                 return -1);
 916
 917         return 0;
 918 }
 919
 920 static ssize_t streams_xattr_pwrite(vfs_handle_struct *handle,
 921                                     files_struct *fsp, const void *data,
 922                                     size_t n, off_t offset)
 923 {
 924         struct stream_io *sio =
 925                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
 926         struct ea_struct ea;
 927         NTSTATUS status;
 928         int ret;
 929
 930         DEBUG(10, ("streams_xattr_pwrite called for %d bytes\n", (int)n));
 931
 932         if (sio == NULL) {
 933                 return SMB_VFS_NEXT_PWRITE(handle, fsp, data, n, offset);
 934         }
 935
 936         if (!streams_xattr_recheck(sio)) {
 937                 return -1;
 938         }
 939
 940         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
 941                               sio->base, sio->xattr_name, &ea);
 942         if (!NT_STATUS_IS_OK(status)) {
 943                 return -1;
 944         }
 945
 946         if ((offset + n) > ea.value.length-1) {
 947                 uint8_t *tmp;
 948
 949                 tmp = talloc_realloc(talloc_tos(), ea.value.data, uint8_t,
 950                                            offset + n + 1);
 951
 952                 if (tmp == NULL) {
 953                         TALLOC_FREE(ea.value.data);
 954                         errno = ENOMEM;
 955                         return -1;
 956                 }
 957                 ea.value.data = tmp;
 958                 ea.value.length = offset + n + 1;
 959                 ea.value.data[offset+n] = 0;
 960         }
 961
 962         memcpy(ea.value.data + offset, data, n);
 963
 964         if (fsp->base_fsp->fh->fd != -1) {
 965                 ret = SMB_VFS_FSETXATTR(fsp->base_fsp,
 966                                 sio->xattr_name,
 967                                 ea.value.data, ea.value.length, 0);
 968         } else {
 969                 ret = SMB_VFS_SETXATTR(fsp->conn,
 970                                        fsp->base_fsp->fsp_name->base_name,
 971                                 sio->xattr_name,
 972                                 ea.value.data, ea.value.length, 0);
 973         }
 974         TALLOC_FREE(ea.value.data);
 975
 976         if (ret == -1) {
 977                 return -1;
 978         }
 979
 980         return n;
 981 }
 982
 983 static ssize_t streams_xattr_pread(vfs_handle_struct *handle,
 984                                    files_struct *fsp, void *data,
 985                                    size_t n, off_t offset)
 986 {
 987         struct stream_io *sio =
 988                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
 989         struct ea_struct ea;
 990         NTSTATUS status;
 991         size_t length, overlap;
 992
 993         DEBUG(10, ("streams_xattr_pread: offset=%d, size=%d\n",
 994                    (int)offset, (int)n));
 995
 996         if (sio == NULL) {
 997                 return SMB_VFS_NEXT_PREAD(handle, fsp, data, n, offset);
 998         }
 999
1000         if (!streams_xattr_recheck(sio)) {
1001                 return -1;
1002         }
1003
1004         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
1005                               sio->base, sio->xattr_name, &ea);
1006         if (!NT_STATUS_IS_OK(status)) {
1007                 return -1;
1008         }
1009
1010         length = ea.value.length-1;
1011
1012         DEBUG(10, ("streams_xattr_pread: get_ea_value returned %d bytes\n",
1013                    (int)length));
1014
1015         /* Attempt to read past EOF. */
1016         if (length <= offset) {
1017                 return 0;
1018         }
1019
1020         overlap = (offset + n) > length ? (length - offset) : n;
1021         memcpy(data, ea.value.data + offset, overlap);
1022
1023         TALLOC_FREE(ea.value.data);
1024         return overlap;
1025 }
1026
1027 static int streams_xattr_ftruncate(struct vfs_handle_struct *handle,
1028                                         struct files_struct *fsp,
1029                                         off_t offset)
1030 {
1031         int ret;
1032         uint8_t *tmp;
1033         struct ea_struct ea;
1034         NTSTATUS status;
1035         struct stream_io *sio =
1036                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
1037
1038         DEBUG(10, ("streams_xattr_ftruncate called for file %s offset %.0f\n",
1039                    fsp_str_dbg(fsp), (double)offset));
1040
1041         if (sio == NULL) {
1042                 return SMB_VFS_NEXT_FTRUNCATE(handle, fsp, offset);
1043         }
1044
1045         if (!streams_xattr_recheck(sio)) {
1046                 return -1;
1047         }
1048
1049         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
1050                               sio->base, sio->xattr_name, &ea);
1051         if (!NT_STATUS_IS_OK(status)) {
1052                 return -1;
1053         }
1054
1055         tmp = talloc_realloc(talloc_tos(), ea.value.data, uint8_t,
1056                                    offset + 1);
1057
1058         if (tmp == NULL) {
1059                 TALLOC_FREE(ea.value.data);
1060                 errno = ENOMEM;
1061                 return -1;
1062         }
1063
1064         /* Did we expand ? */
1065         if (ea.value.length < offset + 1) {
1066                 memset(&tmp[ea.value.length], '\0',
1067                         offset + 1 - ea.value.length);
1068         }
1069
1070         ea.value.data = tmp;
1071         ea.value.length = offset + 1;
1072         ea.value.data[offset] = 0;
1073
1074         if (fsp->base_fsp->fh->fd != -1) {
1075                 ret = SMB_VFS_FSETXATTR(fsp->base_fsp,
1076                                 sio->xattr_name,
1077                                 ea.value.data, ea.value.length, 0);
1078         } else {
1079                 ret = SMB_VFS_SETXATTR(fsp->conn,
1080                                        fsp->base_fsp->fsp_name->base_name,
1081                                 sio->xattr_name,
1082                                 ea.value.data, ea.value.length, 0);
1083         }
1084
1085         TALLOC_FREE(ea.value.data);
1086
1087         if (ret == -1) {
1088                 return -1;
1089         }
1090
1091         return 0;
1092 }
1093
1094 static int streams_xattr_fallocate(struct vfs_handle_struct *handle,
1095                                         struct files_struct *fsp,
1096                                         uint32_t mode,
1097                                         off_t offset,
1098                                         off_t len)
1099 {
1100         struct stream_io *sio =
1101                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
1102
1103         DEBUG(10, ("streams_xattr_fallocate called for file %s offset %.0f"
1104                 "len = %.0f\n",
1105                 fsp_str_dbg(fsp), (double)offset, (double)len));
1106
1107         if (sio == NULL) {
1108                 return SMB_VFS_NEXT_FALLOCATE(handle, fsp, mode, offset, len);
1109         }
1110
1111         if (!streams_xattr_recheck(sio)) {
1112                 return -1;
1113         }
1114
1115         /* Let the pwrite code path handle it. */
1116         errno = ENOSYS;
1117         return -1;
1118 }
1119
1120
1121 static struct vfs_fn_pointers vfs_streams_xattr_fns = {
1122         .fs_capabilities_fn = streams_xattr_fs_capabilities,
1123         .connect_fn = streams_xattr_connect,
1124         .open_fn = streams_xattr_open,
1125         .stat_fn = streams_xattr_stat,
1126         .fstat_fn = streams_xattr_fstat,
1127         .lstat_fn = streams_xattr_lstat,
1128         .pread_fn = streams_xattr_pread,
1129         .pwrite_fn = streams_xattr_pwrite,
1130         .unlink_fn = streams_xattr_unlink,
1131         .rename_fn = streams_xattr_rename,
1132         .ftruncate_fn = streams_xattr_ftruncate,
1133         .fallocate_fn = streams_xattr_fallocate,
1134         .streaminfo_fn = streams_xattr_streaminfo,
1135 };
1136
1137 NTSTATUS vfs_streams_xattr_init(void);
1138 NTSTATUS vfs_streams_xattr_init(void)
1139 {
1140         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "streams_xattr",
1141                                 &vfs_streams_xattr_fns);
1142 }