source3/modules/vfs_streams_depot.c

   1 /*
   2  * Store streams in a separate subdirectory
   3  *
   4  * Copyright (C) Volker Lendecke, 2007
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "includes.h"
  21 #include "smbd/smbd.h"
  22 #include "system/filesys.h"
  23 #include "source3/smbd/dir.h"
  24
  25 #undef DBGC_CLASS
  26 #define DBGC_CLASS DBGC_VFS
  27
  28 /*
  29  * Excerpt from a mail from tridge:
  30  *
  31  * Volker, what I'm thinking of is this:
  32  * /mount-point/.streams/XX/YY/aaaa.bbbb/namedstream1
  33  * /mount-point/.streams/XX/YY/aaaa.bbbb/namedstream2
  34  *
  35  * where XX/YY is a 2 level hash based on the fsid/inode. "aaaa.bbbb"
  36  * is the fsid/inode. "namedstreamX" is a file named after the stream
  37  * name.
  38  */
  39
  40 static uint32_t hash_fn(DATA_BLOB key)
  41 {
  42         uint32_t value; /* Used to compute the hash value.  */
  43         uint32_t i;     /* Used to cycle through random values. */
  44
  45         /* Set the initial value from the key size. */
  46         for (value = 0x238F13AF * key.length, i=0; i < key.length; i++)
  47                 value = (value + (key.data[i] << (i*5 % 24)));
  48
  49         return (1103515243 * value + 12345);
  50 }
  51
  52 /*
  53  * With the hashing scheme based on the inode we need to protect against
  54  * streams showing up on files with re-used inodes. This can happen if we
  55  * create a stream directory from within Samba, and a local process or NFS
  56  * client deletes the file without deleting the streams directory. When the
  57  * inode is re-used and the stream directory is still around, the streams in
  58  * there would be show up as belonging to the new file.
  59  *
  60  * There are several workarounds for this, probably the easiest one is on
  61  * systems which have a true birthtime stat element: When the file has a later
  62  * birthtime than the streams directory, then we have to recreate the
  63  * directory.
  64  *
  65  * The other workaround is to somehow mark the file as generated by Samba with
  66  * something that a NFS client would not do. The closest one is a special
  67  * xattr value being set. On systems which do not support xattrs, it might be
  68  * an option to put in a special ACL entry for a non-existing group.
  69  */
  70
  71 static bool file_is_valid(vfs_handle_struct *handle,
  72                         const struct smb_filename *smb_fname)
  73 {
  74         char buf;
  75         NTSTATUS status;
  76         struct smb_filename *pathref = NULL;
  77         int ret;
  78
  79         DEBUG(10, ("file_is_valid (%s) called\n", smb_fname->base_name));
  80
  81         status = synthetic_pathref(talloc_tos(),
  82                                 handle->conn->cwd_fsp,
  83                                 smb_fname->base_name,
  84                                 NULL,
  85                                 NULL,
  86                                 smb_fname->twrp,
  87                                 smb_fname->flags,
  88                                 &pathref);
  89         if (!NT_STATUS_IS_OK(status)) {
  90                 return false;
  91         }
  92         ret = SMB_VFS_FGETXATTR(pathref->fsp,
  93                                 SAMBA_XATTR_MARKER,
  94                                 &buf,
  95                                 sizeof(buf));
  96         if (ret != sizeof(buf)) {
  97                 int saved_errno = errno;
  98                 DBG_DEBUG("FGETXATTR failed: %s\n", strerror(saved_errno));
  99                 TALLOC_FREE(pathref);
 100                 errno = saved_errno;
 101                 return false;
 102         }
 103
 104         TALLOC_FREE(pathref);
 105
 106         if (buf != '1') {
 107                 DEBUG(10, ("got wrong buffer content: '%c'\n", buf));
 108                 return false;
 109         }
 110
 111         return true;
 112 }
 113
 114 /*
 115  * Return the root of the stream directory. Can be
 116  * external to the share definition but by default
 117  * is "handle->conn->connectpath/.streams".
 118  *
 119  * Note that this is an *absolute* path, starting
 120  * with '/', so the dirfsp being used in the
 121  * calls below isn't looked at.
 122  */
 123
 124 static char *stream_rootdir(vfs_handle_struct *handle,
 125                             TALLOC_CTX *ctx)
 126 {
 127         const struct loadparm_substitution *lp_sub =
 128                 loadparm_s3_global_substitution();
 129         char *tmp;
 130
 131         tmp = talloc_asprintf(ctx,
 132                               "%s/.streams",
 133                               handle->conn->connectpath);
 134         if (tmp == NULL) {
 135                 errno = ENOMEM;
 136                 return NULL;
 137         }
 138
 139         return lp_parm_substituted_string(ctx,
 140                                           lp_sub,
 141                                           SNUM(handle->conn),
 142                                           "streams_depot",
 143                                           "directory",
 144                                           tmp);
 145 }
 146
 147 /**
 148  * Given an smb_filename, determine the stream directory using the file's
 149  * base_name.
 150  */
 151 static char *stream_dir(vfs_handle_struct *handle,
 152                         const struct smb_filename *smb_fname,
 153                         const SMB_STRUCT_STAT *base_sbuf, bool create_it)
 154 {
 155         uint32_t hash;
 156         struct smb_filename *smb_fname_hash = NULL;
 157         char *result = NULL;
 158         SMB_STRUCT_STAT base_sbuf_tmp;
 159         char *tmp = NULL;
 160         uint8_t first, second;
 161         char *id_hex;
 162         struct file_id id;
 163         uint8_t id_buf[16];
 164         bool check_valid;
 165         char *rootdir = NULL;
 166         struct smb_filename *rootdir_fname = NULL;
 167         struct smb_filename *tmp_fname = NULL;
 168         int ret;
 169
 170         check_valid = lp_parm_bool(SNUM(handle->conn),
 171                       "streams_depot", "check_valid", true);
 172
 173         rootdir = stream_rootdir(handle,
 174                                  talloc_tos());
 175         if (rootdir == NULL) {
 176                 errno = ENOMEM;
 177                 goto fail;
 178         }
 179
 180         rootdir_fname = synthetic_smb_fname(talloc_tos(),
 181                                         rootdir,
 182                                         NULL,
 183                                         NULL,
 184                                         smb_fname->twrp,
 185                                         smb_fname->flags);
 186         if (rootdir_fname == NULL) {
 187                 errno = ENOMEM;
 188                 goto fail;
 189         }
 190
 191         /* Stat the base file if it hasn't already been done. */
 192         if (base_sbuf == NULL) {
 193                 struct smb_filename *smb_fname_base;
 194
 195                 smb_fname_base = synthetic_smb_fname(
 196                                         talloc_tos(),
 197                                         smb_fname->base_name,
 198                                         NULL,
 199                                         NULL,
 200                                         smb_fname->twrp,
 201                                         smb_fname->flags);
 202                 if (smb_fname_base == NULL) {
 203                         errno = ENOMEM;
 204                         goto fail;
 205                 }
 206                 if (SMB_VFS_NEXT_STAT(handle, smb_fname_base) == -1) {
 207                         TALLOC_FREE(smb_fname_base);
 208                         goto fail;
 209                 }
 210                 base_sbuf_tmp = smb_fname_base->st;
 211                 TALLOC_FREE(smb_fname_base);
 212         } else {
 213                 base_sbuf_tmp = *base_sbuf;
 214         }
 215
 216         id = SMB_VFS_FILE_ID_CREATE(handle->conn, &base_sbuf_tmp);
 217
 218         push_file_id_16((char *)id_buf, &id);
 219
 220         hash = hash_fn(data_blob_const(id_buf, sizeof(id_buf)));
 221
 222         first = hash & 0xff;
 223         second = (hash >> 8) & 0xff;
 224
 225         id_hex = hex_encode_talloc(talloc_tos(), id_buf, sizeof(id_buf));
 226
 227         if (id_hex == NULL) {
 228                 errno = ENOMEM;
 229                 goto fail;
 230         }
 231
 232         result = talloc_asprintf(talloc_tos(), "%s/%2.2X/%2.2X/%s", rootdir,
 233                                  first, second, id_hex);
 234
 235         TALLOC_FREE(id_hex);
 236
 237         if (result == NULL) {
 238                 errno = ENOMEM;
 239                 return NULL;
 240         }
 241
 242         smb_fname_hash = synthetic_smb_fname(talloc_tos(),
 243                                         result,
 244                                         NULL,
 245                                         NULL,
 246                                         smb_fname->twrp,
 247                                         smb_fname->flags);
 248         if (smb_fname_hash == NULL) {
 249                 errno = ENOMEM;
 250                 goto fail;
 251         }
 252
 253         if (SMB_VFS_NEXT_STAT(handle, smb_fname_hash) == 0) {
 254                 struct smb_filename *smb_fname_new = NULL;
 255                 char *newname;
 256                 bool delete_lost;
 257
 258                 if (!S_ISDIR(smb_fname_hash->st.st_ex_mode)) {
 259                         errno = EINVAL;
 260                         goto fail;
 261                 }
 262
 263                 if (!check_valid ||
 264                     file_is_valid(handle, smb_fname)) {
 265                         return result;
 266                 }
 267
 268                 /*
 269                  * Someone has recreated a file under an existing inode
 270                  * without deleting the streams directory.
 271                  * Move it away or remove if streams_depot:delete_lost is set.
 272                  */
 273
 274         again:
 275                 delete_lost = lp_parm_bool(SNUM(handle->conn), "streams_depot",
 276                                            "delete_lost", false);
 277
 278                 if (delete_lost) {
 279                         DEBUG(3, ("Someone has recreated a file under an "
 280                               "existing inode. Removing: %s\n",
 281                               smb_fname_hash->base_name));
 282                         recursive_rmdir(talloc_tos(), handle->conn,
 283                                         smb_fname_hash);
 284                         SMB_VFS_NEXT_UNLINKAT(handle,
 285                                         handle->conn->cwd_fsp,
 286                                         smb_fname_hash,
 287                                         AT_REMOVEDIR);
 288                 } else {
 289                         newname = talloc_asprintf(talloc_tos(), "lost-%lu",
 290                                                   random());
 291                         DEBUG(3, ("Someone has recreated a file under an "
 292                               "existing inode. Renaming: %s to: %s\n",
 293                               smb_fname_hash->base_name,
 294                               newname));
 295                         if (newname == NULL) {
 296                                 errno = ENOMEM;
 297                                 goto fail;
 298                         }
 299
 300                         smb_fname_new = synthetic_smb_fname(
 301                                                 talloc_tos(),
 302                                                 newname,
 303                                                 NULL,
 304                                                 NULL,
 305                                                 smb_fname->twrp,
 306                                                 smb_fname->flags);
 307                         TALLOC_FREE(newname);
 308                         if (smb_fname_new == NULL) {
 309                                 errno = ENOMEM;
 310                                 goto fail;
 311                         }
 312
 313                         if (SMB_VFS_NEXT_RENAMEAT(handle,
 314                                         handle->conn->cwd_fsp,
 315                                         smb_fname_hash,
 316                                         handle->conn->cwd_fsp,
 317                                         smb_fname_new) == -1) {
 318                                 TALLOC_FREE(smb_fname_new);
 319                                 if ((errno == EEXIST) || (errno == ENOTEMPTY)) {
 320                                         goto again;
 321                                 }
 322                                 goto fail;
 323                         }
 324
 325                         TALLOC_FREE(smb_fname_new);
 326                 }
 327         }
 328
 329         if (!create_it) {
 330                 errno = ENOENT;
 331                 goto fail;
 332         }
 333
 334         ret = SMB_VFS_NEXT_MKDIRAT(handle,
 335                                 handle->conn->cwd_fsp,
 336                                 rootdir_fname,
 337                                 0755);
 338         if ((ret != 0) && (errno != EEXIST)) {
 339                 goto fail;
 340         }
 341
 342         tmp = talloc_asprintf(result, "%s/%2.2X", rootdir, first);
 343         if (tmp == NULL) {
 344                 errno = ENOMEM;
 345                 goto fail;
 346         }
 347
 348         tmp_fname = synthetic_smb_fname(talloc_tos(),
 349                                         tmp,
 350                                         NULL,
 351                                         NULL,
 352                                         smb_fname->twrp,
 353                                         smb_fname->flags);
 354         if (tmp_fname == NULL) {
 355                 errno = ENOMEM;
 356                 goto fail;
 357         }
 358
 359         ret = SMB_VFS_NEXT_MKDIRAT(handle,
 360                                 handle->conn->cwd_fsp,
 361                                 tmp_fname,
 362                                 0755);
 363         if ((ret != 0) && (errno != EEXIST)) {
 364                 goto fail;
 365         }
 366
 367         TALLOC_FREE(tmp);
 368         TALLOC_FREE(tmp_fname);
 369
 370         tmp = talloc_asprintf(result, "%s/%2.2X/%2.2X", rootdir, first,
 371                               second);
 372         if (tmp == NULL) {
 373                 errno = ENOMEM;
 374                 goto fail;
 375         }
 376
 377         tmp_fname = synthetic_smb_fname(talloc_tos(),
 378                                         tmp,
 379                                         NULL,
 380                                         NULL,
 381                                         smb_fname->twrp,
 382                                         smb_fname->flags);
 383         if (tmp_fname == NULL) {
 384                 errno = ENOMEM;
 385                 goto fail;
 386         }
 387
 388         ret = SMB_VFS_NEXT_MKDIRAT(handle,
 389                         handle->conn->cwd_fsp,
 390                         tmp_fname,
 391                         0755);
 392         if ((ret != 0) && (errno != EEXIST)) {
 393                 goto fail;
 394         }
 395
 396         TALLOC_FREE(tmp);
 397         TALLOC_FREE(tmp_fname);
 398
 399         /* smb_fname_hash is the struct smb_filename version of 'result' */
 400         ret = SMB_VFS_NEXT_MKDIRAT(handle,
 401                         handle->conn->cwd_fsp,
 402                         smb_fname_hash,
 403                         0755);
 404         if ((ret != 0) && (errno != EEXIST)) {
 405                 goto fail;
 406         }
 407
 408         TALLOC_FREE(rootdir_fname);
 409         TALLOC_FREE(rootdir);
 410         TALLOC_FREE(tmp_fname);
 411         TALLOC_FREE(smb_fname_hash);
 412         return result;
 413
 414  fail:
 415         TALLOC_FREE(rootdir_fname);
 416         TALLOC_FREE(rootdir);
 417         TALLOC_FREE(tmp_fname);
 418         TALLOC_FREE(smb_fname_hash);
 419         TALLOC_FREE(result);
 420         return NULL;
 421 }
 422 /**
 423  * Given a stream name, populate smb_fname_out with the actual location of the
 424  * stream.
 425  */
 426 static NTSTATUS stream_smb_fname(vfs_handle_struct *handle,
 427                                  const struct stat_ex *base_sbuf,
 428                                  const struct smb_filename *smb_fname,
 429                                  struct smb_filename **smb_fname_out,
 430                                  bool create_dir)
 431 {
 432         char *dirname, *stream_fname;
 433         const char *stype;
 434         NTSTATUS status;
 435
 436         *smb_fname_out = NULL;
 437
 438         stype = strchr_m(smb_fname->stream_name + 1, ':');
 439
 440         if (stype) {
 441                 if (strcasecmp_m(stype, ":$DATA") != 0) {
 442                         return NT_STATUS_INVALID_PARAMETER;
 443                 }
 444         }
 445
 446         dirname = stream_dir(handle, smb_fname, base_sbuf, create_dir);
 447
 448         if (dirname == NULL) {
 449                 status = map_nt_error_from_unix(errno);
 450                 goto fail;
 451         }
 452
 453         stream_fname = talloc_asprintf(talloc_tos(), "%s/%s", dirname,
 454                                        smb_fname->stream_name);
 455
 456         if (stream_fname == NULL) {
 457                 status = NT_STATUS_NO_MEMORY;
 458                 goto fail;
 459         }
 460
 461         if (stype == NULL) {
 462                 /* Append an explicit stream type if one wasn't specified. */
 463                 stream_fname = talloc_asprintf(talloc_tos(), "%s:$DATA",
 464                                                stream_fname);
 465                 if (stream_fname == NULL) {
 466                         status = NT_STATUS_NO_MEMORY;
 467                         goto fail;
 468                 }
 469         } else {
 470                 /* Normalize the stream type to uppercase. */
 471                 if (!strupper_m(strrchr_m(stream_fname, ':') + 1)) {
 472                         status = NT_STATUS_INVALID_PARAMETER;
 473                         goto fail;
 474                 }
 475         }
 476
 477         DEBUG(10, ("stream filename = %s\n", stream_fname));
 478
 479         /* Create an smb_filename with stream_name == NULL. */
 480         *smb_fname_out = synthetic_smb_fname(talloc_tos(),
 481                                         stream_fname,
 482                                         NULL,
 483                                         NULL,
 484                                         smb_fname->twrp,
 485                                         smb_fname->flags);
 486         if (*smb_fname_out == NULL) {
 487                 return NT_STATUS_NO_MEMORY;
 488         }
 489
 490         return NT_STATUS_OK;
 491
 492  fail:
 493         DEBUG(5, ("stream_name failed: %s\n", strerror(errno)));
 494         TALLOC_FREE(*smb_fname_out);
 495         return status;
 496 }
 497
 498 static NTSTATUS walk_streams(vfs_handle_struct *handle,
 499                              struct smb_filename *smb_fname_base,
 500                              char **pdirname,
 501                              bool (*fn)(const struct smb_filename *dirname,
 502                                         const char *dirent,
 503                                         void *private_data),
 504                              void *private_data)
 505 {
 506         char *dirname;
 507         char *rootdir = NULL;
 508         char *orig_connectpath = NULL;
 509         struct smb_filename *dir_smb_fname = NULL;
 510         struct smb_Dir *dir_hnd = NULL;
 511         const char *dname = NULL;
 512         char *talloced = NULL;
 513         NTSTATUS status;
 514
 515         dirname = stream_dir(handle, smb_fname_base, &smb_fname_base->st,
 516                              false);
 517
 518         if (dirname == NULL) {
 519                 if (errno == ENOENT) {
 520                         /*
 521                          * no stream around
 522                          */
 523                         return NT_STATUS_OK;
 524                 }
 525                 return map_nt_error_from_unix(errno);
 526         }
 527
 528         DEBUG(10, ("walk_streams: dirname=%s\n", dirname));
 529
 530         dir_smb_fname = synthetic_smb_fname(talloc_tos(),
 531                                         dirname,
 532                                         NULL,
 533                                         NULL,
 534                                         smb_fname_base->twrp,
 535                                         smb_fname_base->flags);
 536         if (dir_smb_fname == NULL) {
 537                 TALLOC_FREE(dirname);
 538                 return NT_STATUS_NO_MEMORY;
 539         }
 540
 541         /*
 542          * For OpenDir to succeed if the stream rootdir is outside
 543          * the share path, we must temporarily swap out the connect
 544          * path for this share. We're dealing with absolute paths
 545          * here so we don't care about chdir calls.
 546          */
 547         rootdir = stream_rootdir(handle, talloc_tos());
 548         if (rootdir == NULL) {
 549                 TALLOC_FREE(dir_smb_fname);
 550                 TALLOC_FREE(dirname);
 551                 return NT_STATUS_NO_MEMORY;
 552         }
 553
 554         orig_connectpath = handle->conn->connectpath;
 555         handle->conn->connectpath = rootdir;
 556
 557         status = OpenDir(
 558                 talloc_tos(), handle->conn, dir_smb_fname, NULL, 0, &dir_hnd);
 559         if (!NT_STATUS_IS_OK(status)) {
 560                 handle->conn->connectpath = orig_connectpath;
 561                 TALLOC_FREE(rootdir);
 562                 TALLOC_FREE(dir_smb_fname);
 563                 TALLOC_FREE(dirname);
 564                 return status;
 565         }
 566
 567         while ((dname = ReadDirName(dir_hnd, &talloced)) != NULL) {
 568                 if (ISDOT(dname) || ISDOTDOT(dname)) {
 569                         TALLOC_FREE(talloced);
 570                         continue;
 571                 }
 572
 573                 DBG_DEBUG("dirent=%s\n", dname);
 574
 575                 if (!fn(dir_smb_fname, dname, private_data)) {
 576                         TALLOC_FREE(talloced);
 577                         break;
 578                 }
 579                 TALLOC_FREE(talloced);
 580         }
 581
 582         /* Restore the original connectpath. */
 583         handle->conn->connectpath = orig_connectpath;
 584         TALLOC_FREE(rootdir);
 585         TALLOC_FREE(dir_smb_fname);
 586         TALLOC_FREE(dir_hnd);
 587
 588         if (pdirname != NULL) {
 589                 *pdirname = dirname;
 590         }
 591         else {
 592                 TALLOC_FREE(dirname);
 593         }
 594
 595         return NT_STATUS_OK;
 596 }
 597
 598 static int streams_depot_stat(vfs_handle_struct *handle,
 599                               struct smb_filename *smb_fname)
 600 {
 601         struct smb_filename *smb_fname_stream = NULL;
 602         NTSTATUS status;
 603         int ret = -1;
 604
 605         DEBUG(10, ("streams_depot_stat called for [%s]\n",
 606                    smb_fname_str_dbg(smb_fname)));
 607
 608         if (!is_named_stream(smb_fname)) {
 609                 return SMB_VFS_NEXT_STAT(handle, smb_fname);
 610         }
 611
 612         /* Stat the actual stream now. */
 613         status = stream_smb_fname(
 614                 handle, NULL, smb_fname, &smb_fname_stream, false);
 615         if (!NT_STATUS_IS_OK(status)) {
 616                 ret = -1;
 617                 errno = map_errno_from_nt_status(status);
 618                 goto done;
 619         }
 620
 621         ret = SMB_VFS_NEXT_STAT(handle, smb_fname_stream);
 622
 623         /* Update the original smb_fname with the stat info. */
 624         smb_fname->st = smb_fname_stream->st;
 625  done:
 626         TALLOC_FREE(smb_fname_stream);
 627         return ret;
 628 }
 629
 630
 631
 632 static int streams_depot_lstat(vfs_handle_struct *handle,
 633                                struct smb_filename *smb_fname)
 634 {
 635         struct smb_filename *smb_fname_stream = NULL;
 636         NTSTATUS status;
 637         int ret = -1;
 638
 639         DEBUG(10, ("streams_depot_lstat called for [%s]\n",
 640                    smb_fname_str_dbg(smb_fname)));
 641
 642         if (!is_named_stream(smb_fname)) {
 643                 return SMB_VFS_NEXT_LSTAT(handle, smb_fname);
 644         }
 645
 646         /* Stat the actual stream now. */
 647         status = stream_smb_fname(
 648                 handle, NULL, smb_fname, &smb_fname_stream, false);
 649         if (!NT_STATUS_IS_OK(status)) {
 650                 ret = -1;
 651                 errno = map_errno_from_nt_status(status);
 652                 goto done;
 653         }
 654
 655         ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_stream);
 656
 657  done:
 658         TALLOC_FREE(smb_fname_stream);
 659         return ret;
 660 }
 661
 662 static int streams_depot_openat(struct vfs_handle_struct *handle,
 663                                 const struct files_struct *dirfsp,
 664                                 const struct smb_filename *smb_fname,
 665                                 struct files_struct *fsp,
 666                                 const struct vfs_open_how *how)
 667 {
 668         struct smb_filename *smb_fname_stream = NULL;
 669         struct files_struct *fspcwd = NULL;
 670         NTSTATUS status;
 671         bool create_it;
 672         int ret = -1;
 673
 674         if (!is_named_stream(smb_fname)) {
 675                 return SMB_VFS_NEXT_OPENAT(handle,
 676                                            dirfsp,
 677                                            smb_fname,
 678                                            fsp,
 679                                            how);
 680         }
 681
 682         if (how->resolve != 0) {
 683                 errno = ENOSYS;
 684                 return -1;
 685         }
 686
 687         SMB_ASSERT(fsp_is_alternate_stream(fsp));
 688         SMB_ASSERT(dirfsp == NULL);
 689         SMB_ASSERT(VALID_STAT(fsp->base_fsp->fsp_name->st));
 690
 691         create_it = (how->flags & O_CREAT);
 692
 693         /* Determine the stream name, and then open it. */
 694         status = stream_smb_fname(
 695                 handle,
 696                 &fsp->base_fsp->fsp_name->st,
 697                 fsp->fsp_name,
 698                 &smb_fname_stream,
 699                 create_it);
 700         if (!NT_STATUS_IS_OK(status)) {
 701                 ret = -1;
 702                 errno = map_errno_from_nt_status(status);
 703                 goto done;
 704         }
 705
 706         if (create_it) {
 707                 bool check_valid = lp_parm_bool(
 708                         SNUM(handle->conn),
 709                         "streams_depot",
 710                         "check_valid",
 711                         true);
 712
 713                 if (check_valid) {
 714                         char buf = '1';
 715
 716                         DBG_DEBUG("marking file %s as valid\n",
 717                                   fsp->base_fsp->fsp_name->base_name);
 718
 719                         ret = SMB_VFS_FSETXATTR(
 720                                 fsp->base_fsp,
 721                                 SAMBA_XATTR_MARKER,
 722                                 &buf,
 723                                 sizeof(buf),
 724                                 0);
 725
 726                         if (ret == -1) {
 727                                 DBG_DEBUG("FSETXATTR failed: %s\n",
 728                                           strerror(errno));
 729                                 goto done;
 730                         }
 731                 }
 732         }
 733
 734         status = vfs_at_fspcwd(talloc_tos(), handle->conn, &fspcwd);
 735         if (!NT_STATUS_IS_OK(status)) {
 736                 ret = -1;
 737                 errno = map_errno_from_nt_status(status);
 738                 goto done;
 739         }
 740
 741         ret = SMB_VFS_NEXT_OPENAT(handle,
 742                                   fspcwd,
 743                                   smb_fname_stream,
 744                                   fsp,
 745                                   how);
 746
 747  done:
 748         TALLOC_FREE(smb_fname_stream);
 749         TALLOC_FREE(fspcwd);
 750         return ret;
 751 }
 752
 753 static int streams_depot_unlink_internal(vfs_handle_struct *handle,
 754                                 struct files_struct *dirfsp,
 755                                 const struct smb_filename *smb_fname,
 756                                 int flags)
 757 {
 758         struct smb_filename *full_fname = NULL;
 759         char *dirname = NULL;
 760         int ret = -1;
 761
 762         full_fname = full_path_from_dirfsp_atname(talloc_tos(),
 763                                                   dirfsp,
 764                                                   smb_fname);
 765         if (full_fname == NULL) {
 766                 return -1;
 767         }
 768
 769         DEBUG(10, ("streams_depot_unlink called for %s\n",
 770                    smb_fname_str_dbg(full_fname)));
 771
 772         /* If there is a valid stream, just unlink the stream and return. */
 773         if (is_named_stream(full_fname)) {
 774                 struct smb_filename *smb_fname_stream = NULL;
 775                 NTSTATUS status;
 776
 777                 status = stream_smb_fname(
 778                         handle, NULL, full_fname, &smb_fname_stream, false);
 779                 TALLOC_FREE(full_fname);
 780                 if (!NT_STATUS_IS_OK(status)) {
 781                         errno = map_errno_from_nt_status(status);
 782                         return -1;
 783                 }
 784
 785                 ret = SMB_VFS_NEXT_UNLINKAT(handle,
 786                                 dirfsp->conn->cwd_fsp,
 787                                 smb_fname_stream,
 788                                 0);
 789
 790                 TALLOC_FREE(smb_fname_stream);
 791                 return ret;
 792         }
 793
 794         /*
 795          * We potentially need to delete the per-inode streams directory
 796          */
 797
 798         if (full_fname->flags & SMB_FILENAME_POSIX_PATH) {
 799                 ret = SMB_VFS_NEXT_LSTAT(handle, full_fname);
 800         } else {
 801                 ret = SMB_VFS_NEXT_STAT(handle, full_fname);
 802                 if (ret == -1 && (errno == ENOENT || errno == ELOOP)) {
 803                         if (VALID_STAT(smb_fname->st) &&
 804                                         S_ISLNK(smb_fname->st.st_ex_mode)) {
 805                                 /*
 806                                  * Original name was a link - Could be
 807                                  * trying to remove a dangling symlink.
 808                                  */
 809                                 ret = SMB_VFS_NEXT_LSTAT(handle, full_fname);
 810                         }
 811                 }
 812         }
 813         if (ret == -1) {
 814                 TALLOC_FREE(full_fname);
 815                 return -1;
 816         }
 817
 818         /*
 819          * We know the unlink should succeed as the ACL
 820          * check is already done in the caller. Remove the
 821          * file *after* the streams.
 822          */
 823         dirname = stream_dir(handle,
 824                              full_fname,
 825                              &full_fname->st,
 826                              false);
 827         TALLOC_FREE(full_fname);
 828         if (dirname != NULL) {
 829                 struct smb_filename *smb_fname_dir = NULL;
 830
 831                 smb_fname_dir = synthetic_smb_fname(talloc_tos(),
 832                                                     dirname,
 833                                                     NULL,
 834                                                     NULL,
 835                                                     smb_fname->twrp,
 836                                                     smb_fname->flags);
 837                 if (smb_fname_dir == NULL) {
 838                         TALLOC_FREE(dirname);
 839                         errno = ENOMEM;
 840                         return -1;
 841                 }
 842
 843                 SMB_VFS_NEXT_UNLINKAT(handle,
 844                                       dirfsp->conn->cwd_fsp,
 845                                       smb_fname_dir,
 846                                       AT_REMOVEDIR);
 847                 TALLOC_FREE(smb_fname_dir);
 848                 TALLOC_FREE(dirname);
 849         }
 850
 851         ret = SMB_VFS_NEXT_UNLINKAT(handle,
 852                                 dirfsp,
 853                                 smb_fname,
 854                                 flags);
 855         return ret;
 856 }
 857
 858 static int streams_depot_rmdir_internal(vfs_handle_struct *handle,
 859                         struct files_struct *dirfsp,
 860                         const struct smb_filename *smb_fname)
 861 {
 862         struct smb_filename *full_fname = NULL;
 863         struct smb_filename *smb_fname_base = NULL;
 864         int ret = -1;
 865
 866         full_fname = full_path_from_dirfsp_atname(talloc_tos(),
 867                                                   dirfsp,
 868                                                   smb_fname);
 869         if (full_fname == NULL) {
 870                 return -1;
 871         }
 872
 873         DBG_DEBUG("called for %s\n", full_fname->base_name);
 874
 875         /*
 876          * We potentially need to delete the per-inode streams directory
 877          */
 878
 879         smb_fname_base = synthetic_smb_fname(talloc_tos(),
 880                                 full_fname->base_name,
 881                                 NULL,
 882                                 NULL,
 883                                 full_fname->twrp,
 884                                 full_fname->flags);
 885         TALLOC_FREE(full_fname);
 886         if (smb_fname_base == NULL) {
 887                 errno = ENOMEM;
 888                 return -1;
 889         }
 890
 891         if (smb_fname_base->flags & SMB_FILENAME_POSIX_PATH) {
 892                 ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_base);
 893         } else {
 894                 ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
 895         }
 896
 897         if (ret == -1) {
 898                 TALLOC_FREE(smb_fname_base);
 899                 return -1;
 900         }
 901
 902         /*
 903          * We know the rmdir should succeed as the ACL
 904          * check is already done in the caller. Remove the
 905          * directory *after* the streams.
 906          */
 907         {
 908                 char *dirname = stream_dir(handle, smb_fname_base,
 909                                            &smb_fname_base->st, false);
 910
 911                 if (dirname != NULL) {
 912                         struct smb_filename *smb_fname_dir =
 913                                 synthetic_smb_fname(talloc_tos(),
 914                                                 dirname,
 915                                                 NULL,
 916                                                 NULL,
 917                                                 smb_fname->twrp,
 918                                                 smb_fname->flags);
 919                         if (smb_fname_dir == NULL) {
 920                                 TALLOC_FREE(smb_fname_base);
 921                                 TALLOC_FREE(dirname);
 922                                 errno = ENOMEM;
 923                                 return -1;
 924                         }
 925                         SMB_VFS_NEXT_UNLINKAT(handle,
 926                                         dirfsp->conn->cwd_fsp,
 927                                         smb_fname_dir,
 928                                         AT_REMOVEDIR);
 929                         TALLOC_FREE(smb_fname_dir);
 930                 }
 931                 TALLOC_FREE(dirname);
 932         }
 933
 934         ret = SMB_VFS_NEXT_UNLINKAT(handle,
 935                                 dirfsp,
 936                                 smb_fname,
 937                                 AT_REMOVEDIR);
 938         TALLOC_FREE(smb_fname_base);
 939         return ret;
 940 }
 941
 942 static int streams_depot_unlinkat(vfs_handle_struct *handle,
 943                         struct files_struct *dirfsp,
 944                         const struct smb_filename *smb_fname,
 945                         int flags)
 946 {
 947         int ret;
 948         if (flags & AT_REMOVEDIR) {
 949                 ret = streams_depot_rmdir_internal(handle,
 950                                 dirfsp,
 951                                 smb_fname);
 952         } else {
 953                 ret = streams_depot_unlink_internal(handle,
 954                                 dirfsp,
 955                                 smb_fname,
 956                                 flags);
 957         }
 958         return ret;
 959 }
 960
 961 static int streams_depot_renameat(vfs_handle_struct *handle,
 962                                 files_struct *srcfsp,
 963                                 const struct smb_filename *smb_fname_src,
 964                                 files_struct *dstfsp,
 965                                 const struct smb_filename *smb_fname_dst)
 966 {
 967         struct smb_filename *smb_fname_src_stream = NULL;
 968         struct smb_filename *smb_fname_dst_stream = NULL;
 969         struct smb_filename *full_src = NULL;
 970         struct smb_filename *full_dst = NULL;
 971         bool src_is_stream, dst_is_stream;
 972         NTSTATUS status;
 973         int ret = -1;
 974
 975         DEBUG(10, ("streams_depot_renameat called for %s => %s\n",
 976                    smb_fname_str_dbg(smb_fname_src),
 977                    smb_fname_str_dbg(smb_fname_dst)));
 978
 979         src_is_stream = is_ntfs_stream_smb_fname(smb_fname_src);
 980         dst_is_stream = is_ntfs_stream_smb_fname(smb_fname_dst);
 981
 982         if (!src_is_stream && !dst_is_stream) {
 983                 return SMB_VFS_NEXT_RENAMEAT(handle,
 984                                         srcfsp,
 985                                         smb_fname_src,
 986                                         dstfsp,
 987                                         smb_fname_dst);
 988         }
 989
 990         /* for now don't allow renames from or to the default stream */
 991         if (is_ntfs_default_stream_smb_fname(smb_fname_src) ||
 992             is_ntfs_default_stream_smb_fname(smb_fname_dst)) {
 993                 errno = ENOSYS;
 994                 goto done;
 995         }
 996
 997         full_src = full_path_from_dirfsp_atname(talloc_tos(),
 998                                                 srcfsp,
 999                                                 smb_fname_src);
1000         if (full_src == NULL) {
1001                 errno = ENOMEM;
1002                 goto done;
1003         }
1004
1005         full_dst = full_path_from_dirfsp_atname(talloc_tos(),
1006                                                 dstfsp,
1007                                                 smb_fname_dst);
1008         if (full_dst == NULL) {
1009                 errno = ENOMEM;
1010                 goto done;
1011         }
1012
1013         status = stream_smb_fname(
1014                 handle, NULL, full_src, &smb_fname_src_stream, false);
1015         if (!NT_STATUS_IS_OK(status)) {
1016                 errno = map_errno_from_nt_status(status);
1017                 goto done;
1018         }
1019
1020         status = stream_smb_fname(
1021                 handle, NULL, full_dst, &smb_fname_dst_stream, false);
1022         if (!NT_STATUS_IS_OK(status)) {
1023                 errno = map_errno_from_nt_status(status);
1024                 goto done;
1025         }
1026
1027         /*
1028          * We must use handle->conn->cwd_fsp as
1029          * srcfsp and dstfsp directory handles here
1030          * as we used the full pathname from the cwd dir
1031          * to calculate the streams directory and filename
1032          * within.
1033          */
1034         ret = SMB_VFS_NEXT_RENAMEAT(handle,
1035                                 handle->conn->cwd_fsp,
1036                                 smb_fname_src_stream,
1037                                 handle->conn->cwd_fsp,
1038                                 smb_fname_dst_stream);
1039
1040 done:
1041         TALLOC_FREE(smb_fname_src_stream);
1042         TALLOC_FREE(smb_fname_dst_stream);
1043         return ret;
1044 }
1045
1046 static bool add_one_stream(TALLOC_CTX *mem_ctx, unsigned int *num_streams,
1047                            struct stream_struct **streams,
1048                            const char *name, off_t size,
1049                            off_t alloc_size)
1050 {
1051         struct stream_struct *tmp;
1052
1053         tmp = talloc_realloc(mem_ctx, *streams, struct stream_struct,
1054                                    (*num_streams)+1);
1055         if (tmp == NULL) {
1056                 return false;
1057         }
1058
1059         tmp[*num_streams].name = talloc_strdup(tmp, name);
1060         if (tmp[*num_streams].name == NULL) {
1061                 return false;
1062         }
1063
1064         tmp[*num_streams].size = size;
1065         tmp[*num_streams].alloc_size = alloc_size;
1066
1067         *streams = tmp;
1068         *num_streams += 1;
1069         return true;
1070 }
1071
1072 struct streaminfo_state {
1073         TALLOC_CTX *mem_ctx;
1074         vfs_handle_struct *handle;
1075         unsigned int num_streams;
1076         struct stream_struct *streams;
1077         NTSTATUS status;
1078 };
1079
1080 static bool collect_one_stream(const struct smb_filename *dirfname,
1081                                const char *dirent,
1082                                void *private_data)
1083 {
1084         const char *dirname = dirfname->base_name;
1085         struct streaminfo_state *state =
1086                 (struct streaminfo_state *)private_data;
1087         struct smb_filename *smb_fname = NULL;
1088         char *sname = NULL;
1089         bool ret;
1090
1091         sname = talloc_asprintf(talloc_tos(), "%s/%s", dirname, dirent);
1092         if (sname == NULL) {
1093                 state->status = NT_STATUS_NO_MEMORY;
1094                 ret = false;
1095                 goto out;
1096         }
1097
1098         smb_fname = synthetic_smb_fname(talloc_tos(),
1099                                         sname,
1100                                         NULL,
1101                                         NULL,
1102                                         dirfname->twrp,
1103                                         0);
1104         if (smb_fname == NULL) {
1105                 state->status = NT_STATUS_NO_MEMORY;
1106                 ret = false;
1107                 goto out;
1108         }
1109
1110         if (SMB_VFS_NEXT_STAT(state->handle, smb_fname) == -1) {
1111                 DEBUG(10, ("Could not stat %s: %s\n", sname,
1112                            strerror(errno)));
1113                 ret = true;
1114                 goto out;
1115         }
1116
1117         if (!add_one_stream(state->mem_ctx,
1118                             &state->num_streams, &state->streams,
1119                             dirent, smb_fname->st.st_ex_size,
1120                             SMB_VFS_GET_ALLOC_SIZE(state->handle->conn, NULL,
1121                                                    &smb_fname->st))) {
1122                 state->status = NT_STATUS_NO_MEMORY;
1123                 ret = false;
1124                 goto out;
1125         }
1126
1127         ret = true;
1128  out:
1129         TALLOC_FREE(sname);
1130         TALLOC_FREE(smb_fname);
1131         return ret;
1132 }
1133
1134 static NTSTATUS streams_depot_fstreaminfo(vfs_handle_struct *handle,
1135                                          struct files_struct *fsp,
1136                                          TALLOC_CTX *mem_ctx,
1137                                          unsigned int *pnum_streams,
1138                                          struct stream_struct **pstreams)
1139 {
1140         struct smb_filename *smb_fname_base = NULL;
1141         int ret;
1142         NTSTATUS status;
1143         struct streaminfo_state state;
1144
1145         smb_fname_base = synthetic_smb_fname(talloc_tos(),
1146                                         fsp->fsp_name->base_name,
1147                                         NULL,
1148                                         NULL,
1149                                         fsp->fsp_name->twrp,
1150                                         fsp->fsp_name->flags);
1151         if (smb_fname_base == NULL) {
1152                 return NT_STATUS_NO_MEMORY;
1153         }
1154
1155         ret = SMB_VFS_NEXT_FSTAT(handle, fsp, &smb_fname_base->st);
1156         if (ret == -1) {
1157                 status = map_nt_error_from_unix(errno);
1158                 goto out;
1159         }
1160
1161         state.streams = *pstreams;
1162         state.num_streams = *pnum_streams;
1163         state.mem_ctx = mem_ctx;
1164         state.handle = handle;
1165         state.status = NT_STATUS_OK;
1166
1167         status = walk_streams(handle,
1168                                 smb_fname_base,
1169                                 NULL,
1170                                 collect_one_stream,
1171                                 &state);
1172
1173         if (!NT_STATUS_IS_OK(status)) {
1174                 TALLOC_FREE(state.streams);
1175                 goto out;
1176         }
1177
1178         if (!NT_STATUS_IS_OK(state.status)) {
1179                 TALLOC_FREE(state.streams);
1180                 status = state.status;
1181                 goto out;
1182         }
1183
1184         *pnum_streams = state.num_streams;
1185         *pstreams = state.streams;
1186         status = SMB_VFS_NEXT_FSTREAMINFO(handle,
1187                                 fsp->base_fsp ? fsp->base_fsp : fsp,
1188                                 mem_ctx,
1189                                 pnum_streams,
1190                                 pstreams);
1191
1192  out:
1193         TALLOC_FREE(smb_fname_base);
1194         return status;
1195 }
1196
1197 static uint32_t streams_depot_fs_capabilities(struct vfs_handle_struct *handle,
1198                         enum timestamp_set_resolution *p_ts_res)
1199 {
1200         return SMB_VFS_NEXT_FS_CAPABILITIES(handle, p_ts_res) | FILE_NAMED_STREAMS;
1201 }
1202
1203 static struct vfs_fn_pointers vfs_streams_depot_fns = {
1204         .fs_capabilities_fn = streams_depot_fs_capabilities,
1205         .openat_fn = streams_depot_openat,
1206         .stat_fn = streams_depot_stat,
1207         .lstat_fn = streams_depot_lstat,
1208         .unlinkat_fn = streams_depot_unlinkat,
1209         .renameat_fn = streams_depot_renameat,
1210         .fstreaminfo_fn = streams_depot_fstreaminfo,
1211 };
1212
1213 static_decl_vfs;
1214 NTSTATUS vfs_streams_depot_init(TALLOC_CTX *ctx)
1215 {
1216         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "streams_depot",
1217                                 &vfs_streams_depot_fns);
1218 }