source3/modules/vfs_streams_xattr.c

   1 /*
   2  * Store streams in xattrs
   3  *
   4  * Copyright (C) Volker Lendecke, 2008
   5  *
   6  * Partly based on James Peach's Darwin module, which is
   7  *
   8  * Copyright (C) James Peach 2006-2007
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 3 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  22  */
  23
  24 #include "includes.h"
  25 #include "smbd/smbd.h"
  26 #include "system/filesys.h"
  27 #include "../lib/crypto/md5.h"
  28
  29 #undef DBGC_CLASS
  30 #define DBGC_CLASS DBGC_VFS
  31
  32 struct stream_io {
  33         char *base;
  34         char *xattr_name;
  35         void *fsp_name_ptr;
  36         files_struct *fsp;
  37         vfs_handle_struct *handle;
  38 };
  39
  40 static SMB_INO_T stream_inode(const SMB_STRUCT_STAT *sbuf, const char *sname)
  41 {
  42         struct MD5Context ctx;
  43         unsigned char hash[16];
  44         SMB_INO_T result;
  45         char *upper_sname;
  46
  47         DEBUG(10, ("stream_inode called for %lu/%lu [%s]\n",
  48                    (unsigned long)sbuf->st_ex_dev,
  49                    (unsigned long)sbuf->st_ex_ino, sname));
  50
  51         upper_sname = talloc_strdup_upper(talloc_tos(), sname);
  52         SMB_ASSERT(upper_sname != NULL);
  53
  54         MD5Init(&ctx);
  55         MD5Update(&ctx, (const unsigned char *)&(sbuf->st_ex_dev),
  56                   sizeof(sbuf->st_ex_dev));
  57         MD5Update(&ctx, (const unsigned char *)&(sbuf->st_ex_ino),
  58                   sizeof(sbuf->st_ex_ino));
  59         MD5Update(&ctx, (unsigned char *)upper_sname,
  60                   talloc_get_size(upper_sname)-1);
  61         MD5Final(hash, &ctx);
  62
  63         TALLOC_FREE(upper_sname);
  64
  65         /* Hopefully all the variation is in the lower 4 (or 8) bytes! */
  66         memcpy(&result, hash, sizeof(result));
  67
  68         DEBUG(10, ("stream_inode returns %lu\n", (unsigned long)result));
  69
  70         return result;
  71 }
  72
  73 static ssize_t get_xattr_size(connection_struct *conn,
  74                                 files_struct *fsp,
  75                                 const char *fname,
  76                                 const char *xattr_name)
  77 {
  78         NTSTATUS status;
  79         struct ea_struct ea;
  80         ssize_t result;
  81
  82         status = get_ea_value(talloc_tos(), conn, fsp, fname,
  83                               xattr_name, &ea);
  84
  85         if (!NT_STATUS_IS_OK(status)) {
  86                 return -1;
  87         }
  88
  89         result = ea.value.length-1;
  90         TALLOC_FREE(ea.value.data);
  91         return result;
  92 }
  93
  94 /**
  95  * Given a stream name, populate xattr_name with the xattr name to use for
  96  * accessing the stream.
  97  */
  98 static NTSTATUS streams_xattr_get_name(TALLOC_CTX *ctx,
  99                                        const char *stream_name,
 100                                        char **xattr_name)
 101 {
 102         char *stype;
 103
 104         stype = strchr_m(stream_name + 1, ':');
 105
 106         *xattr_name = talloc_asprintf(ctx, "%s%s",
 107                                       SAMBA_XATTR_DOSSTREAM_PREFIX,
 108                                       stream_name + 1);
 109         if (*xattr_name == NULL) {
 110                 return NT_STATUS_NO_MEMORY;
 111         }
 112
 113         if (stype == NULL) {
 114                 /* Append an explicit stream type if one wasn't specified. */
 115                 *xattr_name = talloc_asprintf(ctx, "%s:$DATA",
 116                                                *xattr_name);
 117                 if (*xattr_name == NULL) {
 118                         return NT_STATUS_NO_MEMORY;
 119                 }
 120         } else {
 121                 /* Normalize the stream type to upercase. */
 122                 strupper_m(strrchr_m(*xattr_name, ':') + 1);
 123         }
 124
 125         DEBUG(10, ("xattr_name: %s, stream_name: %s\n", *xattr_name,
 126                    stream_name));
 127
 128         return NT_STATUS_OK;
 129 }
 130
 131 static bool streams_xattr_recheck(struct stream_io *sio)
 132 {
 133         NTSTATUS status;
 134         char *xattr_name = NULL;
 135
 136         if (sio->fsp->fsp_name == sio->fsp_name_ptr) {
 137                 return true;
 138         }
 139
 140         if (sio->fsp->fsp_name->stream_name == NULL) {
 141                 /* how can this happen */
 142                 errno = EINVAL;
 143                 return false;
 144         }
 145
 146         status = streams_xattr_get_name(talloc_tos(),
 147                                         sio->fsp->fsp_name->stream_name,
 148                                         &xattr_name);
 149         if (!NT_STATUS_IS_OK(status)) {
 150                 return false;
 151         }
 152
 153         TALLOC_FREE(sio->xattr_name);
 154         TALLOC_FREE(sio->base);
 155         sio->xattr_name = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(sio->handle, sio->fsp),
 156                                         xattr_name);
 157         sio->base = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(sio->handle, sio->fsp),
 158                                   sio->fsp->fsp_name->base_name);
 159         sio->fsp_name_ptr = sio->fsp->fsp_name;
 160
 161         TALLOC_FREE(xattr_name);
 162
 163         if ((sio->xattr_name == NULL) || (sio->base == NULL)) {
 164                 return false;
 165         }
 166
 167         return true;
 168 }
 169
 170 /**
 171  * Helper to stat/lstat the base file of an smb_fname.
 172  */
 173 static int streams_xattr_stat_base(vfs_handle_struct *handle,
 174                                    struct smb_filename *smb_fname,
 175                                    bool follow_links)
 176 {
 177         char *tmp_stream_name;
 178         int result;
 179
 180         tmp_stream_name = smb_fname->stream_name;
 181         smb_fname->stream_name = NULL;
 182         if (follow_links) {
 183                 result = SMB_VFS_NEXT_STAT(handle, smb_fname);
 184         } else {
 185                 result = SMB_VFS_NEXT_LSTAT(handle, smb_fname);
 186         }
 187         smb_fname->stream_name = tmp_stream_name;
 188         return result;
 189 }
 190
 191 static int streams_xattr_fstat(vfs_handle_struct *handle, files_struct *fsp,
 192                                SMB_STRUCT_STAT *sbuf)
 193 {
 194         struct smb_filename *smb_fname_base = NULL;
 195         NTSTATUS status;
 196         int ret = -1;
 197         struct stream_io *io = (struct stream_io *)
 198                 VFS_FETCH_FSP_EXTENSION(handle, fsp);
 199
 200         DEBUG(10, ("streams_xattr_fstat called for %d\n", fsp->fh->fd));
 201
 202         if (io == NULL || fsp->base_fsp == NULL) {
 203                 return SMB_VFS_NEXT_FSTAT(handle, fsp, sbuf);
 204         }
 205
 206         if (!streams_xattr_recheck(io)) {
 207                 return -1;
 208         }
 209
 210         /* Create an smb_filename with stream_name == NULL. */
 211         status = create_synthetic_smb_fname(talloc_tos(),
 212                                             io->base,
 213                                             NULL, NULL,
 214                                             &smb_fname_base);
 215         if (!NT_STATUS_IS_OK(status)) {
 216                 errno = map_errno_from_nt_status(status);
 217                 return -1;
 218         }
 219
 220         if (lp_posix_pathnames()) {
 221                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_base);
 222         } else {
 223                 ret = SMB_VFS_STAT(handle->conn, smb_fname_base);
 224         }
 225         *sbuf = smb_fname_base->st;
 226         TALLOC_FREE(smb_fname_base);
 227
 228         if (ret == -1) {
 229                 return -1;
 230         }
 231
 232         sbuf->st_ex_size = get_xattr_size(handle->conn, fsp->base_fsp,
 233                                         io->base, io->xattr_name);
 234         if (sbuf->st_ex_size == -1) {
 235                 return -1;
 236         }
 237
 238         DEBUG(10, ("sbuf->st_ex_size = %d\n", (int)sbuf->st_ex_size));
 239
 240         sbuf->st_ex_ino = stream_inode(sbuf, io->xattr_name);
 241         sbuf->st_ex_mode &= ~S_IFMT;
 242         sbuf->st_ex_mode |= S_IFREG;
 243         sbuf->st_ex_blocks = sbuf->st_ex_size / STAT_ST_BLOCKSIZE + 1;
 244
 245         return 0;
 246 }
 247
 248 static int streams_xattr_stat(vfs_handle_struct *handle,
 249                               struct smb_filename *smb_fname)
 250 {
 251         NTSTATUS status;
 252         int result = -1;
 253         char *xattr_name = NULL;
 254
 255         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 256                 return SMB_VFS_NEXT_STAT(handle, smb_fname);
 257         }
 258
 259         /* Note if lp_posix_paths() is true, we can never
 260          * get here as is_ntfs_stream_smb_fname() is
 261          * always false. So we never need worry about
 262          * not following links here. */
 263
 264         /* If the default stream is requested, just stat the base file. */
 265         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 266                 return streams_xattr_stat_base(handle, smb_fname, true);
 267         }
 268
 269         /* Populate the stat struct with info from the base file. */
 270         if (streams_xattr_stat_base(handle, smb_fname, true) == -1) {
 271                 return -1;
 272         }
 273
 274         /* Derive the xattr name to lookup. */
 275         status = streams_xattr_get_name(talloc_tos(), smb_fname->stream_name,
 276                                         &xattr_name);
 277         if (!NT_STATUS_IS_OK(status)) {
 278                 errno = map_errno_from_nt_status(status);
 279                 return -1;
 280         }
 281
 282         /* Augment the base file's stat information before returning. */
 283         smb_fname->st.st_ex_size = get_xattr_size(handle->conn, NULL,
 284                                                   smb_fname->base_name,
 285                                                   xattr_name);
 286         if (smb_fname->st.st_ex_size == -1) {
 287                 errno = ENOENT;
 288                 result = -1;
 289                 goto fail;
 290         }
 291
 292         smb_fname->st.st_ex_ino = stream_inode(&smb_fname->st, xattr_name);
 293         smb_fname->st.st_ex_mode &= ~S_IFMT;
 294         smb_fname->st.st_ex_mode |= S_IFREG;
 295         smb_fname->st.st_ex_blocks =
 296             smb_fname->st.st_ex_size / STAT_ST_BLOCKSIZE + 1;
 297
 298         result = 0;
 299  fail:
 300         TALLOC_FREE(xattr_name);
 301         return result;
 302 }
 303
 304 static int streams_xattr_lstat(vfs_handle_struct *handle,
 305                                struct smb_filename *smb_fname)
 306 {
 307         NTSTATUS status;
 308         int result = -1;
 309         char *xattr_name = NULL;
 310
 311         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 312                 return SMB_VFS_NEXT_LSTAT(handle, smb_fname);
 313         }
 314
 315         /* If the default stream is requested, just stat the base file. */
 316         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 317                 return streams_xattr_stat_base(handle, smb_fname, false);
 318         }
 319
 320         /* Populate the stat struct with info from the base file. */
 321         if (streams_xattr_stat_base(handle, smb_fname, false) == -1) {
 322                 return -1;
 323         }
 324
 325         /* Derive the xattr name to lookup. */
 326         status = streams_xattr_get_name(talloc_tos(), smb_fname->stream_name,
 327                                         &xattr_name);
 328         if (!NT_STATUS_IS_OK(status)) {
 329                 errno = map_errno_from_nt_status(status);
 330                 return -1;
 331         }
 332
 333         /* Augment the base file's stat information before returning. */
 334         smb_fname->st.st_ex_size = get_xattr_size(handle->conn, NULL,
 335                                                   smb_fname->base_name,
 336                                                   xattr_name);
 337         if (smb_fname->st.st_ex_size == -1) {
 338                 errno = ENOENT;
 339                 result = -1;
 340                 goto fail;
 341         }
 342
 343         smb_fname->st.st_ex_ino = stream_inode(&smb_fname->st, xattr_name);
 344         smb_fname->st.st_ex_mode &= ~S_IFMT;
 345         smb_fname->st.st_ex_mode |= S_IFREG;
 346         smb_fname->st.st_ex_blocks =
 347             smb_fname->st.st_ex_size / STAT_ST_BLOCKSIZE + 1;
 348
 349         result = 0;
 350
 351  fail:
 352         TALLOC_FREE(xattr_name);
 353         return result;
 354 }
 355
 356 static int streams_xattr_open(vfs_handle_struct *handle,
 357                               struct smb_filename *smb_fname,
 358                               files_struct *fsp, int flags, mode_t mode)
 359 {
 360         NTSTATUS status;
 361         struct smb_filename *smb_fname_base = NULL;
 362         struct stream_io *sio;
 363         struct ea_struct ea;
 364         char *xattr_name = NULL;
 365         int baseflags;
 366         int hostfd = -1;
 367
 368         DEBUG(10, ("streams_xattr_open called for %s\n",
 369                    smb_fname_str_dbg(smb_fname)));
 370
 371         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 372                 return SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
 373         }
 374
 375         /* If the default stream is requested, just open the base file. */
 376         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 377                 char *tmp_stream_name;
 378                 int ret;
 379
 380                 tmp_stream_name = smb_fname->stream_name;
 381                 smb_fname->stream_name = NULL;
 382
 383                 ret = SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
 384
 385                 smb_fname->stream_name = tmp_stream_name;
 386
 387                 return ret;
 388         }
 389
 390         status = streams_xattr_get_name(talloc_tos(), smb_fname->stream_name,
 391                                         &xattr_name);
 392         if (!NT_STATUS_IS_OK(status)) {
 393                 errno = map_errno_from_nt_status(status);
 394                 goto fail;
 395         }
 396
 397         /* Create an smb_filename with stream_name == NULL. */
 398         status = create_synthetic_smb_fname(talloc_tos(),
 399                                             smb_fname->base_name,
 400                                             NULL, NULL,
 401                                             &smb_fname_base);
 402         if (!NT_STATUS_IS_OK(status)) {
 403                 errno = map_errno_from_nt_status(status);
 404                 goto fail;
 405         }
 406
 407         /*
 408          * We use baseflags to turn off nasty side-effects when opening the
 409          * underlying file.
 410          */
 411         baseflags = flags;
 412         baseflags &= ~O_TRUNC;
 413         baseflags &= ~O_EXCL;
 414         baseflags &= ~O_CREAT;
 415
 416         hostfd = SMB_VFS_OPEN(handle->conn, smb_fname_base, fsp,
 417                               baseflags, mode);
 418
 419         TALLOC_FREE(smb_fname_base);
 420
 421         /* It is legit to open a stream on a directory, but the base
 422          * fd has to be read-only.
 423          */
 424         if ((hostfd == -1) && (errno == EISDIR)) {
 425                 baseflags &= ~O_ACCMODE;
 426                 baseflags |= O_RDONLY;
 427                 hostfd = SMB_VFS_OPEN(handle->conn, smb_fname, fsp, baseflags,
 428                                       mode);
 429         }
 430
 431         if (hostfd == -1) {
 432                 goto fail;
 433         }
 434
 435         status = get_ea_value(talloc_tos(), handle->conn, NULL,
 436                               smb_fname->base_name, xattr_name, &ea);
 437
 438         DEBUG(10, ("get_ea_value returned %s\n", nt_errstr(status)));
 439
 440         if (!NT_STATUS_IS_OK(status)
 441             && !NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND)) {
 442                 /*
 443                  * The base file is not there. This is an error even if we got
 444                  * O_CREAT, the higher levels should have created the base
 445                  * file for us.
 446                  */
 447                 DEBUG(10, ("streams_xattr_open: base file %s not around, "
 448                            "returning ENOENT\n", smb_fname->base_name));
 449                 errno = ENOENT;
 450                 goto fail;
 451         }
 452
 453         if (!NT_STATUS_IS_OK(status)) {
 454                 /*
 455                  * The attribute does not exist
 456                  */
 457
 458                 if (flags & O_CREAT) {
 459                         /*
 460                          * Darn, xattrs need at least 1 byte
 461                          */
 462                         char null = '\0';
 463
 464                         DEBUG(10, ("creating attribute %s on file %s\n",
 465                                    xattr_name, smb_fname->base_name));
 466
 467                         if (fsp->base_fsp->fh->fd != -1) {
 468                                 if (SMB_VFS_FSETXATTR(
 469                                         fsp->base_fsp, xattr_name,
 470                                         &null, sizeof(null),
 471                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 472                                         goto fail;
 473                                 }
 474                         } else {
 475                                 if (SMB_VFS_SETXATTR(
 476                                         handle->conn, smb_fname->base_name,
 477                                         xattr_name, &null, sizeof(null),
 478                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 479                                         goto fail;
 480                                 }
 481                         }
 482                 }
 483         }
 484
 485         if (flags & O_TRUNC) {
 486                 char null = '\0';
 487                 if (fsp->base_fsp->fh->fd != -1) {
 488                         if (SMB_VFS_FSETXATTR(
 489                                         fsp->base_fsp, xattr_name,
 490                                         &null, sizeof(null),
 491                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 492                                 goto fail;
 493                         }
 494                 } else {
 495                         if (SMB_VFS_SETXATTR(
 496                                         handle->conn, smb_fname->base_name,
 497                                         xattr_name, &null, sizeof(null),
 498                                         flags & O_EXCL ? XATTR_CREATE : 0) == -1) {
 499                                 goto fail;
 500                         }
 501                 }
 502         }
 503
 504         sio = (struct stream_io *)VFS_ADD_FSP_EXTENSION(handle, fsp,
 505                                                         struct stream_io,
 506                                                         NULL);
 507         if (sio == NULL) {
 508                 errno = ENOMEM;
 509                 goto fail;
 510         }
 511
 512         sio->xattr_name = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(handle, fsp),
 513                                         xattr_name);
 514         sio->base = talloc_strdup(VFS_MEMCTX_FSP_EXTENSION(handle, fsp),
 515                                   smb_fname->base_name);
 516         sio->fsp_name_ptr = fsp->fsp_name;
 517         sio->handle = handle;
 518         sio->fsp = fsp;
 519
 520         if ((sio->xattr_name == NULL) || (sio->base == NULL)) {
 521                 errno = ENOMEM;
 522                 goto fail;
 523         }
 524
 525         return hostfd;
 526
 527  fail:
 528         if (hostfd >= 0) {
 529                 /*
 530                  * BUGBUGBUG -- we would need to call fd_close_posix here, but
 531                  * we don't have a full fsp yet
 532                  */
 533                 SMB_VFS_CLOSE(fsp);
 534         }
 535
 536         return -1;
 537 }
 538
 539 static int streams_xattr_unlink(vfs_handle_struct *handle,
 540                                 const struct smb_filename *smb_fname)
 541 {
 542         NTSTATUS status;
 543         int ret = -1;
 544         char *xattr_name;
 545
 546         if (!is_ntfs_stream_smb_fname(smb_fname)) {
 547                 return SMB_VFS_NEXT_UNLINK(handle, smb_fname);
 548         }
 549
 550         /* If the default stream is requested, just open the base file. */
 551         if (is_ntfs_default_stream_smb_fname(smb_fname)) {
 552                 struct smb_filename *smb_fname_base = NULL;
 553
 554                 status = copy_smb_filename(talloc_tos(), smb_fname,
 555                                             &smb_fname_base);
 556                 if (!NT_STATUS_IS_OK(status)) {
 557                         errno = map_errno_from_nt_status(status);
 558                         return -1;
 559                 }
 560
 561                 ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname_base);
 562
 563                 TALLOC_FREE(smb_fname_base);
 564                 return ret;
 565         }
 566
 567         status = streams_xattr_get_name(talloc_tos(), smb_fname->stream_name,
 568                                         &xattr_name);
 569         if (!NT_STATUS_IS_OK(status)) {
 570                 errno = map_errno_from_nt_status(status);
 571                 goto fail;
 572         }
 573
 574         ret = SMB_VFS_REMOVEXATTR(handle->conn, smb_fname->base_name, xattr_name);
 575
 576         if ((ret == -1) && (errno == ENOATTR)) {
 577                 errno = ENOENT;
 578                 goto fail;
 579         }
 580
 581         ret = 0;
 582
 583  fail:
 584         TALLOC_FREE(xattr_name);
 585         return ret;
 586 }
 587
 588 static int streams_xattr_rename(vfs_handle_struct *handle,
 589                                 const struct smb_filename *smb_fname_src,
 590                                 const struct smb_filename *smb_fname_dst)
 591 {
 592         NTSTATUS status;
 593         int ret = -1;
 594         char *src_xattr_name = NULL;
 595         char *dst_xattr_name = NULL;
 596         bool src_is_stream, dst_is_stream;
 597         ssize_t oret;
 598         ssize_t nret;
 599         struct ea_struct ea;
 600
 601         src_is_stream = is_ntfs_stream_smb_fname(smb_fname_src);
 602         dst_is_stream = is_ntfs_stream_smb_fname(smb_fname_dst);
 603
 604         if (!src_is_stream && !dst_is_stream) {
 605                 return SMB_VFS_NEXT_RENAME(handle, smb_fname_src,
 606                                            smb_fname_dst);
 607         }
 608
 609         /* For now don't allow renames from or to the default stream. */
 610         if (is_ntfs_default_stream_smb_fname(smb_fname_src) ||
 611             is_ntfs_default_stream_smb_fname(smb_fname_dst)) {
 612                 errno = ENOSYS;
 613                 goto done;
 614         }
 615
 616         /* Don't rename if the streams are identical. */
 617         if (strcasecmp_m(smb_fname_src->stream_name,
 618                        smb_fname_dst->stream_name) == 0) {
 619                 goto done;
 620         }
 621
 622         /* Get the xattr names. */
 623         status = streams_xattr_get_name(talloc_tos(),
 624                                         smb_fname_src->stream_name,
 625                                         &src_xattr_name);
 626         if (!NT_STATUS_IS_OK(status)) {
 627                 errno = map_errno_from_nt_status(status);
 628                 goto fail;
 629         }
 630         status = streams_xattr_get_name(talloc_tos(),
 631                                         smb_fname_dst->stream_name,
 632                                         &dst_xattr_name);
 633         if (!NT_STATUS_IS_OK(status)) {
 634                 errno = map_errno_from_nt_status(status);
 635                 goto fail;
 636         }
 637
 638         /* read the old stream */
 639         status = get_ea_value(talloc_tos(), handle->conn, NULL,
 640                               smb_fname_src->base_name, src_xattr_name, &ea);
 641         if (!NT_STATUS_IS_OK(status)) {
 642                 errno = ENOENT;
 643                 goto fail;
 644         }
 645
 646         /* (over)write the new stream */
 647         nret = SMB_VFS_SETXATTR(handle->conn, smb_fname_src->base_name,
 648                                 dst_xattr_name, ea.value.data, ea.value.length,
 649                                 0);
 650         if (nret < 0) {
 651                 if (errno == ENOATTR) {
 652                         errno = ENOENT;
 653                 }
 654                 goto fail;
 655         }
 656
 657         /* remove the old stream */
 658         oret = SMB_VFS_REMOVEXATTR(handle->conn, smb_fname_src->base_name,
 659                                    src_xattr_name);
 660         if (oret < 0) {
 661                 if (errno == ENOATTR) {
 662                         errno = ENOENT;
 663                 }
 664                 goto fail;
 665         }
 666
 667  done:
 668         errno = 0;
 669         ret = 0;
 670  fail:
 671         TALLOC_FREE(src_xattr_name);
 672         TALLOC_FREE(dst_xattr_name);
 673         return ret;
 674 }
 675
 676 static NTSTATUS walk_xattr_streams(connection_struct *conn, files_struct *fsp,
 677                                    const char *fname,
 678                                    bool (*fn)(struct ea_struct *ea,
 679                                               void *private_data),
 680                                    void *private_data)
 681 {
 682         NTSTATUS status;
 683         char **names;
 684         size_t i, num_names;
 685         size_t prefix_len = strlen(SAMBA_XATTR_DOSSTREAM_PREFIX);
 686
 687         status = get_ea_names_from_file(talloc_tos(), 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                 if (strncmp(names[i], SAMBA_XATTR_DOSSTREAM_PREFIX,
 697                             prefix_len) != 0) {
 698                         continue;
 699                 }
 700
 701                 status = get_ea_value(names, conn, fsp, fname, names[i], &ea);
 702                 if (!NT_STATUS_IS_OK(status)) {
 703                         DEBUG(10, ("Could not get ea %s for file %s: %s\n",
 704                                    names[i], fname, nt_errstr(status)));
 705                         continue;
 706                 }
 707
 708                 ea.name = talloc_asprintf(ea.value.data, ":%s",
 709                                           names[i] + prefix_len);
 710                 if (ea.name == NULL) {
 711                         DEBUG(0, ("talloc failed\n"));
 712                         continue;
 713                 }
 714
 715                 if (!fn(&ea, private_data)) {
 716                         TALLOC_FREE(ea.value.data);
 717                         return NT_STATUS_OK;
 718                 }
 719
 720                 TALLOC_FREE(ea.value.data);
 721         }
 722
 723         TALLOC_FREE(names);
 724         return NT_STATUS_OK;
 725 }
 726
 727 static bool add_one_stream(TALLOC_CTX *mem_ctx, unsigned int *num_streams,
 728                            struct stream_struct **streams,
 729                            const char *name, SMB_OFF_T size,
 730                            SMB_OFF_T alloc_size)
 731 {
 732         struct stream_struct *tmp;
 733
 734         tmp = talloc_realloc(mem_ctx, *streams, struct stream_struct,
 735                                    (*num_streams)+1);
 736         if (tmp == NULL) {
 737                 return false;
 738         }
 739
 740         tmp[*num_streams].name = talloc_strdup(tmp, name);
 741         if (tmp[*num_streams].name == NULL) {
 742                 return false;
 743         }
 744
 745         tmp[*num_streams].size = size;
 746         tmp[*num_streams].alloc_size = alloc_size;
 747
 748         *streams = tmp;
 749         *num_streams += 1;
 750         return true;
 751 }
 752
 753 struct streaminfo_state {
 754         TALLOC_CTX *mem_ctx;
 755         vfs_handle_struct *handle;
 756         unsigned int num_streams;
 757         struct stream_struct *streams;
 758         NTSTATUS status;
 759 };
 760
 761 static bool collect_one_stream(struct ea_struct *ea, void *private_data)
 762 {
 763         struct streaminfo_state *state =
 764                 (struct streaminfo_state *)private_data;
 765
 766         if (!add_one_stream(state->mem_ctx,
 767                             &state->num_streams, &state->streams,
 768                             ea->name, ea->value.length-1,
 769                             smb_roundup(state->handle->conn,
 770                                         ea->value.length-1))) {
 771                 state->status = NT_STATUS_NO_MEMORY;
 772                 return false;
 773         }
 774
 775         return true;
 776 }
 777
 778 static NTSTATUS streams_xattr_streaminfo(vfs_handle_struct *handle,
 779                                          struct files_struct *fsp,
 780                                          const char *fname,
 781                                          TALLOC_CTX *mem_ctx,
 782                                          unsigned int *pnum_streams,
 783                                          struct stream_struct **pstreams)
 784 {
 785         SMB_STRUCT_STAT sbuf;
 786         int ret;
 787         NTSTATUS status;
 788         struct streaminfo_state state;
 789
 790         if ((fsp != NULL) && (fsp->fh->fd != -1)) {
 791                 ret = SMB_VFS_FSTAT(fsp, &sbuf);
 792         }
 793         else {
 794                 struct smb_filename *smb_fname = NULL;
 795                 status = create_synthetic_smb_fname(talloc_tos(), fname, NULL,
 796                                                     NULL, &smb_fname);
 797                 if (!NT_STATUS_IS_OK(status)) {
 798                         return status;
 799                 }
 800                 if (lp_posix_pathnames()) {
 801                         ret = SMB_VFS_LSTAT(handle->conn, smb_fname);
 802                 } else {
 803                         ret = SMB_VFS_STAT(handle->conn, smb_fname);
 804                 }
 805                 sbuf = smb_fname->st;
 806                 TALLOC_FREE(smb_fname);
 807         }
 808
 809         if (ret == -1) {
 810                 return map_nt_error_from_unix(errno);
 811         }
 812
 813         state.streams = NULL;
 814         state.num_streams = 0;
 815
 816         if (!S_ISDIR(sbuf.st_ex_mode)) {
 817                 if (!add_one_stream(mem_ctx,
 818                                     &state.num_streams, &state.streams,
 819                                     "::$DATA", sbuf.st_ex_size,
 820                                     SMB_VFS_GET_ALLOC_SIZE(handle->conn, fsp,
 821                                                            &sbuf))) {
 822                         return NT_STATUS_NO_MEMORY;
 823                 }
 824         }
 825
 826         state.mem_ctx = mem_ctx;
 827         state.handle = handle;
 828         state.status = NT_STATUS_OK;
 829
 830         status = walk_xattr_streams(handle->conn, fsp, fname,
 831                                     collect_one_stream, &state);
 832
 833         if (!NT_STATUS_IS_OK(status)) {
 834                 TALLOC_FREE(state.streams);
 835                 return status;
 836         }
 837
 838         if (!NT_STATUS_IS_OK(state.status)) {
 839                 TALLOC_FREE(state.streams);
 840                 return state.status;
 841         }
 842
 843         *pnum_streams = state.num_streams;
 844         *pstreams = state.streams;
 845         return NT_STATUS_OK;
 846 }
 847
 848 static uint32_t streams_xattr_fs_capabilities(struct vfs_handle_struct *handle,
 849                         enum timestamp_set_resolution *p_ts_res)
 850 {
 851         return SMB_VFS_NEXT_FS_CAPABILITIES(handle, p_ts_res) | FILE_NAMED_STREAMS;
 852 }
 853
 854 static ssize_t streams_xattr_pwrite(vfs_handle_struct *handle,
 855                                     files_struct *fsp, const void *data,
 856                                     size_t n, SMB_OFF_T offset)
 857 {
 858         struct stream_io *sio =
 859                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
 860         struct ea_struct ea;
 861         NTSTATUS status;
 862         int ret;
 863
 864         DEBUG(10, ("streams_xattr_pwrite called for %d bytes\n", (int)n));
 865
 866         if (sio == NULL) {
 867                 return SMB_VFS_NEXT_PWRITE(handle, fsp, data, n, offset);
 868         }
 869
 870         if (!streams_xattr_recheck(sio)) {
 871                 return -1;
 872         }
 873
 874         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
 875                               sio->base, sio->xattr_name, &ea);
 876         if (!NT_STATUS_IS_OK(status)) {
 877                 return -1;
 878         }
 879
 880         if ((offset + n) > ea.value.length-1) {
 881                 uint8 *tmp;
 882
 883                 tmp = talloc_realloc(talloc_tos(), ea.value.data, uint8,
 884                                            offset + n + 1);
 885
 886                 if (tmp == NULL) {
 887                         TALLOC_FREE(ea.value.data);
 888                         errno = ENOMEM;
 889                         return -1;
 890                 }
 891                 ea.value.data = tmp;
 892                 ea.value.length = offset + n + 1;
 893                 ea.value.data[offset+n] = 0;
 894         }
 895
 896         memcpy(ea.value.data + offset, data, n);
 897
 898         if (fsp->base_fsp->fh->fd != -1) {
 899                 ret = SMB_VFS_FSETXATTR(fsp->base_fsp,
 900                                 sio->xattr_name,
 901                                 ea.value.data, ea.value.length, 0);
 902         } else {
 903                 ret = SMB_VFS_SETXATTR(fsp->conn,
 904                                        fsp->base_fsp->fsp_name->base_name,
 905                                 sio->xattr_name,
 906                                 ea.value.data, ea.value.length, 0);
 907         }
 908         TALLOC_FREE(ea.value.data);
 909
 910         if (ret == -1) {
 911                 return -1;
 912         }
 913
 914         return n;
 915 }
 916
 917 static ssize_t streams_xattr_pread(vfs_handle_struct *handle,
 918                                    files_struct *fsp, void *data,
 919                                    size_t n, SMB_OFF_T offset)
 920 {
 921         struct stream_io *sio =
 922                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
 923         struct ea_struct ea;
 924         NTSTATUS status;
 925         size_t length, overlap;
 926
 927         DEBUG(10, ("streams_xattr_pread: offset=%d, size=%d\n",
 928                    (int)offset, (int)n));
 929
 930         if (sio == NULL) {
 931                 return SMB_VFS_NEXT_PREAD(handle, fsp, data, n, offset);
 932         }
 933
 934         if (!streams_xattr_recheck(sio)) {
 935                 return -1;
 936         }
 937
 938         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
 939                               sio->base, sio->xattr_name, &ea);
 940         if (!NT_STATUS_IS_OK(status)) {
 941                 return -1;
 942         }
 943
 944         length = ea.value.length-1;
 945
 946         DEBUG(10, ("streams_xattr_pread: get_ea_value returned %d bytes\n",
 947                    (int)length));
 948
 949         /* Attempt to read past EOF. */
 950         if (length <= offset) {
 951                 return 0;
 952         }
 953
 954         overlap = (offset + n) > length ? (length - offset) : n;
 955         memcpy(data, ea.value.data + offset, overlap);
 956
 957         TALLOC_FREE(ea.value.data);
 958         return overlap;
 959 }
 960
 961 static int streams_xattr_ftruncate(struct vfs_handle_struct *handle,
 962                                         struct files_struct *fsp,
 963                                         SMB_OFF_T offset)
 964 {
 965         int ret;
 966         uint8 *tmp;
 967         struct ea_struct ea;
 968         NTSTATUS status;
 969         struct stream_io *sio =
 970                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
 971
 972         DEBUG(10, ("streams_xattr_ftruncate called for file %s offset %.0f\n",
 973                    fsp_str_dbg(fsp), (double)offset));
 974
 975         if (sio == NULL) {
 976                 return SMB_VFS_NEXT_FTRUNCATE(handle, fsp, offset);
 977         }
 978
 979         if (!streams_xattr_recheck(sio)) {
 980                 return -1;
 981         }
 982
 983         status = get_ea_value(talloc_tos(), handle->conn, fsp->base_fsp,
 984                               sio->base, sio->xattr_name, &ea);
 985         if (!NT_STATUS_IS_OK(status)) {
 986                 return -1;
 987         }
 988
 989         tmp = talloc_realloc(talloc_tos(), ea.value.data, uint8,
 990                                    offset + 1);
 991
 992         if (tmp == NULL) {
 993                 TALLOC_FREE(ea.value.data);
 994                 errno = ENOMEM;
 995                 return -1;
 996         }
 997
 998         /* Did we expand ? */
 999         if (ea.value.length < offset + 1) {
1000                 memset(&tmp[ea.value.length], '\0',
1001                         offset + 1 - ea.value.length);
1002         }
1003
1004         ea.value.data = tmp;
1005         ea.value.length = offset + 1;
1006         ea.value.data[offset] = 0;
1007
1008         if (fsp->base_fsp->fh->fd != -1) {
1009                 ret = SMB_VFS_FSETXATTR(fsp->base_fsp,
1010                                 sio->xattr_name,
1011                                 ea.value.data, ea.value.length, 0);
1012         } else {
1013                 ret = SMB_VFS_SETXATTR(fsp->conn,
1014                                        fsp->base_fsp->fsp_name->base_name,
1015                                 sio->xattr_name,
1016                                 ea.value.data, ea.value.length, 0);
1017         }
1018
1019         TALLOC_FREE(ea.value.data);
1020
1021         if (ret == -1) {
1022                 return -1;
1023         }
1024
1025         return 0;
1026 }
1027
1028 static int streams_xattr_fallocate(struct vfs_handle_struct *handle,
1029                                         struct files_struct *fsp,
1030                                         enum vfs_fallocate_mode mode,
1031                                         SMB_OFF_T offset,
1032                                         SMB_OFF_T len)
1033 {
1034         struct stream_io *sio =
1035                 (struct stream_io *)VFS_FETCH_FSP_EXTENSION(handle, fsp);
1036
1037         DEBUG(10, ("streams_xattr_fallocate called for file %s offset %.0f"
1038                 "len = %.0f\n",
1039                 fsp_str_dbg(fsp), (double)offset, (double)len));
1040
1041         if (sio == NULL) {
1042                 return SMB_VFS_NEXT_FALLOCATE(handle, fsp, mode, offset, len);
1043         }
1044
1045         if (!streams_xattr_recheck(sio)) {
1046                 return errno;
1047         }
1048
1049         /* Let the pwrite code path handle it. */
1050         return ENOSYS;
1051 }
1052
1053
1054 static struct vfs_fn_pointers vfs_streams_xattr_fns = {
1055         .fs_capabilities = streams_xattr_fs_capabilities,
1056         .open_fn = streams_xattr_open,
1057         .stat = streams_xattr_stat,
1058         .fstat = streams_xattr_fstat,
1059         .lstat = streams_xattr_lstat,
1060         .pread = streams_xattr_pread,
1061         .pwrite = streams_xattr_pwrite,
1062         .unlink = streams_xattr_unlink,
1063         .rename = streams_xattr_rename,
1064         .ftruncate = streams_xattr_ftruncate,
1065         .fallocate = streams_xattr_fallocate,
1066         .streaminfo = streams_xattr_streaminfo,
1067 };
1068
1069 NTSTATUS vfs_streams_xattr_init(void);
1070 NTSTATUS vfs_streams_xattr_init(void)
1071 {
1072         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "streams_xattr",
1073                                 &vfs_streams_xattr_fns);
1074 }