1 /* 2 * Copyright (c) 2000-2005 Silicon Graphics, Inc. 3 * Copyright (c) 2013 Red Hat, Inc. 4 * All Rights Reserved. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it would be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 18 */ 19 #include "xfs.h" 20 #include "xfs_fs.h" 21 #include "xfs_format.h" 22 #include "xfs_log_format.h" 23 #include "xfs_trans_resv.h" 24 #include "xfs_bit.h" 25 #include "xfs_mount.h" 26 #include "xfs_da_format.h" 27 #include "xfs_da_btree.h" 28 #include "xfs_inode.h" 29 #include "xfs_trans.h" 30 #include "xfs_inode_item.h" 31 #include "xfs_bmap.h" 32 #include "xfs_attr.h" 33 #include "xfs_attr_sf.h" 34 #include "xfs_attr_remote.h" 35 #include "xfs_attr_leaf.h" 36 #include "xfs_error.h" 37 #include "xfs_trace.h" 38 #include "xfs_buf_item.h" 39 #include "xfs_cksum.h" 40 #include "xfs_dir2.h" 41 42 STATIC int 43 xfs_attr_shortform_compare(const void *a, const void *b) 44 { 45 xfs_attr_sf_sort_t *sa, *sb; 46 47 sa = (xfs_attr_sf_sort_t *)a; 48 sb = (xfs_attr_sf_sort_t *)b; 49 if (sa->hash < sb->hash) { 50 return -1; 51 } else if (sa->hash > sb->hash) { 52 return 1; 53 } else { 54 return sa->entno - sb->entno; 55 } 56 } 57 58 #define XFS_ISRESET_CURSOR(cursor) \ 59 (!((cursor)->initted) && !((cursor)->hashval) && \ 60 !((cursor)->blkno) && !((cursor)->offset)) 61 /* 62 * Copy out entries of shortform attribute lists for attr_list(). 63 * Shortform attribute lists are not stored in hashval sorted order. 64 * If the output buffer is not large enough to hold them all, then we 65 * we have to calculate each entries' hashvalue and sort them before 66 * we can begin returning them to the user. 67 */ 68 static int 69 xfs_attr_shortform_list(xfs_attr_list_context_t *context) 70 { 71 attrlist_cursor_kern_t *cursor; 72 xfs_attr_sf_sort_t *sbuf, *sbp; 73 xfs_attr_shortform_t *sf; 74 xfs_attr_sf_entry_t *sfe; 75 xfs_inode_t *dp; 76 int sbsize, nsbuf, count, i; 77 78 ASSERT(context != NULL); 79 dp = context->dp; 80 ASSERT(dp != NULL); 81 ASSERT(dp->i_afp != NULL); 82 sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data; 83 ASSERT(sf != NULL); 84 if (!sf->hdr.count) 85 return 0; 86 cursor = context->cursor; 87 ASSERT(cursor != NULL); 88 89 trace_xfs_attr_list_sf(context); 90 91 /* 92 * If the buffer is large enough and the cursor is at the start, 93 * do not bother with sorting since we will return everything in 94 * one buffer and another call using the cursor won't need to be 95 * made. 96 * Note the generous fudge factor of 16 overhead bytes per entry. 97 * If bufsize is zero then put_listent must be a search function 98 * and can just scan through what we have. 99 */ 100 if (context->bufsize == 0 || 101 (XFS_ISRESET_CURSOR(cursor) && 102 (dp->i_afp->if_bytes + sf->hdr.count * 16) < context->bufsize)) { 103 for (i = 0, sfe = &sf->list[0]; i < sf->hdr.count; i++) { 104 context->put_listent(context, 105 sfe->flags, 106 sfe->nameval, 107 (int)sfe->namelen, 108 (int)sfe->valuelen); 109 /* 110 * Either search callback finished early or 111 * didn't fit it all in the buffer after all. 112 */ 113 if (context->seen_enough) 114 break; 115 sfe = XFS_ATTR_SF_NEXTENTRY(sfe); 116 } 117 trace_xfs_attr_list_sf_all(context); 118 return 0; 119 } 120 121 /* do no more for a search callback */ 122 if (context->bufsize == 0) 123 return 0; 124 125 /* 126 * It didn't all fit, so we have to sort everything on hashval. 127 */ 128 sbsize = sf->hdr.count * sizeof(*sbuf); 129 sbp = sbuf = kmem_alloc(sbsize, KM_SLEEP | KM_NOFS); 130 131 /* 132 * Scan the attribute list for the rest of the entries, storing 133 * the relevant info from only those that match into a buffer. 134 */ 135 nsbuf = 0; 136 for (i = 0, sfe = &sf->list[0]; i < sf->hdr.count; i++) { 137 if (unlikely( 138 ((char *)sfe < (char *)sf) || 139 ((char *)sfe >= ((char *)sf + dp->i_afp->if_bytes)))) { 140 XFS_CORRUPTION_ERROR("xfs_attr_shortform_list", 141 XFS_ERRLEVEL_LOW, 142 context->dp->i_mount, sfe); 143 kmem_free(sbuf); 144 return -EFSCORRUPTED; 145 } 146 147 sbp->entno = i; 148 sbp->hash = xfs_da_hashname(sfe->nameval, sfe->namelen); 149 sbp->name = sfe->nameval; 150 sbp->namelen = sfe->namelen; 151 /* These are bytes, and both on-disk, don't endian-flip */ 152 sbp->valuelen = sfe->valuelen; 153 sbp->flags = sfe->flags; 154 sfe = XFS_ATTR_SF_NEXTENTRY(sfe); 155 sbp++; 156 nsbuf++; 157 } 158 159 /* 160 * Sort the entries on hash then entno. 161 */ 162 xfs_sort(sbuf, nsbuf, sizeof(*sbuf), xfs_attr_shortform_compare); 163 164 /* 165 * Re-find our place IN THE SORTED LIST. 166 */ 167 count = 0; 168 cursor->initted = 1; 169 cursor->blkno = 0; 170 for (sbp = sbuf, i = 0; i < nsbuf; i++, sbp++) { 171 if (sbp->hash == cursor->hashval) { 172 if (cursor->offset == count) { 173 break; 174 } 175 count++; 176 } else if (sbp->hash > cursor->hashval) { 177 break; 178 } 179 } 180 if (i == nsbuf) { 181 kmem_free(sbuf); 182 return 0; 183 } 184 185 /* 186 * Loop putting entries into the user buffer. 187 */ 188 for ( ; i < nsbuf; i++, sbp++) { 189 if (cursor->hashval != sbp->hash) { 190 cursor->hashval = sbp->hash; 191 cursor->offset = 0; 192 } 193 context->put_listent(context, 194 sbp->flags, 195 sbp->name, 196 sbp->namelen, 197 sbp->valuelen); 198 if (context->seen_enough) 199 break; 200 cursor->offset++; 201 } 202 203 kmem_free(sbuf); 204 return 0; 205 } 206 207 STATIC int 208 xfs_attr_node_list(xfs_attr_list_context_t *context) 209 { 210 attrlist_cursor_kern_t *cursor; 211 xfs_attr_leafblock_t *leaf; 212 xfs_da_intnode_t *node; 213 struct xfs_attr3_icleaf_hdr leafhdr; 214 struct xfs_da3_icnode_hdr nodehdr; 215 struct xfs_da_node_entry *btree; 216 int error, i; 217 struct xfs_buf *bp; 218 struct xfs_inode *dp = context->dp; 219 struct xfs_mount *mp = dp->i_mount; 220 221 trace_xfs_attr_node_list(context); 222 223 cursor = context->cursor; 224 cursor->initted = 1; 225 226 /* 227 * Do all sorts of validation on the passed-in cursor structure. 228 * If anything is amiss, ignore the cursor and look up the hashval 229 * starting from the btree root. 230 */ 231 bp = NULL; 232 if (cursor->blkno > 0) { 233 error = xfs_da3_node_read(NULL, dp, cursor->blkno, -1, 234 &bp, XFS_ATTR_FORK); 235 if ((error != 0) && (error != -EFSCORRUPTED)) 236 return error; 237 if (bp) { 238 struct xfs_attr_leaf_entry *entries; 239 240 node = bp->b_addr; 241 switch (be16_to_cpu(node->hdr.info.magic)) { 242 case XFS_DA_NODE_MAGIC: 243 case XFS_DA3_NODE_MAGIC: 244 trace_xfs_attr_list_wrong_blk(context); 245 xfs_trans_brelse(NULL, bp); 246 bp = NULL; 247 break; 248 case XFS_ATTR_LEAF_MAGIC: 249 case XFS_ATTR3_LEAF_MAGIC: 250 leaf = bp->b_addr; 251 xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, 252 &leafhdr, leaf); 253 entries = xfs_attr3_leaf_entryp(leaf); 254 if (cursor->hashval > be32_to_cpu( 255 entries[leafhdr.count - 1].hashval)) { 256 trace_xfs_attr_list_wrong_blk(context); 257 xfs_trans_brelse(NULL, bp); 258 bp = NULL; 259 } else if (cursor->hashval <= be32_to_cpu( 260 entries[0].hashval)) { 261 trace_xfs_attr_list_wrong_blk(context); 262 xfs_trans_brelse(NULL, bp); 263 bp = NULL; 264 } 265 break; 266 default: 267 trace_xfs_attr_list_wrong_blk(context); 268 xfs_trans_brelse(NULL, bp); 269 bp = NULL; 270 } 271 } 272 } 273 274 /* 275 * We did not find what we expected given the cursor's contents, 276 * so we start from the top and work down based on the hash value. 277 * Note that start of node block is same as start of leaf block. 278 */ 279 if (bp == NULL) { 280 cursor->blkno = 0; 281 for (;;) { 282 __uint16_t magic; 283 284 error = xfs_da3_node_read(NULL, dp, 285 cursor->blkno, -1, &bp, 286 XFS_ATTR_FORK); 287 if (error) 288 return error; 289 node = bp->b_addr; 290 magic = be16_to_cpu(node->hdr.info.magic); 291 if (magic == XFS_ATTR_LEAF_MAGIC || 292 magic == XFS_ATTR3_LEAF_MAGIC) 293 break; 294 if (magic != XFS_DA_NODE_MAGIC && 295 magic != XFS_DA3_NODE_MAGIC) { 296 XFS_CORRUPTION_ERROR("xfs_attr_node_list(3)", 297 XFS_ERRLEVEL_LOW, 298 context->dp->i_mount, 299 node); 300 xfs_trans_brelse(NULL, bp); 301 return -EFSCORRUPTED; 302 } 303 304 dp->d_ops->node_hdr_from_disk(&nodehdr, node); 305 btree = dp->d_ops->node_tree_p(node); 306 for (i = 0; i < nodehdr.count; btree++, i++) { 307 if (cursor->hashval 308 <= be32_to_cpu(btree->hashval)) { 309 cursor->blkno = be32_to_cpu(btree->before); 310 trace_xfs_attr_list_node_descend(context, 311 btree); 312 break; 313 } 314 } 315 if (i == nodehdr.count) { 316 xfs_trans_brelse(NULL, bp); 317 return 0; 318 } 319 xfs_trans_brelse(NULL, bp); 320 } 321 } 322 ASSERT(bp != NULL); 323 324 /* 325 * Roll upward through the blocks, processing each leaf block in 326 * order. As long as there is space in the result buffer, keep 327 * adding the information. 328 */ 329 for (;;) { 330 leaf = bp->b_addr; 331 xfs_attr3_leaf_list_int(bp, context); 332 xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf); 333 if (context->seen_enough || leafhdr.forw == 0) 334 break; 335 cursor->blkno = leafhdr.forw; 336 xfs_trans_brelse(NULL, bp); 337 error = xfs_attr3_leaf_read(NULL, dp, cursor->blkno, -1, &bp); 338 if (error) 339 return error; 340 } 341 xfs_trans_brelse(NULL, bp); 342 return 0; 343 } 344 345 /* 346 * Copy out attribute list entries for attr_list(), for leaf attribute lists. 347 */ 348 void 349 xfs_attr3_leaf_list_int( 350 struct xfs_buf *bp, 351 struct xfs_attr_list_context *context) 352 { 353 struct attrlist_cursor_kern *cursor; 354 struct xfs_attr_leafblock *leaf; 355 struct xfs_attr3_icleaf_hdr ichdr; 356 struct xfs_attr_leaf_entry *entries; 357 struct xfs_attr_leaf_entry *entry; 358 int i; 359 struct xfs_mount *mp = context->dp->i_mount; 360 361 trace_xfs_attr_list_leaf(context); 362 363 leaf = bp->b_addr; 364 xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf); 365 entries = xfs_attr3_leaf_entryp(leaf); 366 367 cursor = context->cursor; 368 cursor->initted = 1; 369 370 /* 371 * Re-find our place in the leaf block if this is a new syscall. 372 */ 373 if (context->resynch) { 374 entry = &entries[0]; 375 for (i = 0; i < ichdr.count; entry++, i++) { 376 if (be32_to_cpu(entry->hashval) == cursor->hashval) { 377 if (cursor->offset == context->dupcnt) { 378 context->dupcnt = 0; 379 break; 380 } 381 context->dupcnt++; 382 } else if (be32_to_cpu(entry->hashval) > 383 cursor->hashval) { 384 context->dupcnt = 0; 385 break; 386 } 387 } 388 if (i == ichdr.count) { 389 trace_xfs_attr_list_notfound(context); 390 return; 391 } 392 } else { 393 entry = &entries[0]; 394 i = 0; 395 } 396 context->resynch = 0; 397 398 /* 399 * We have found our place, start copying out the new attributes. 400 */ 401 for (; i < ichdr.count; entry++, i++) { 402 char *name; 403 int namelen, valuelen; 404 405 if (be32_to_cpu(entry->hashval) != cursor->hashval) { 406 cursor->hashval = be32_to_cpu(entry->hashval); 407 cursor->offset = 0; 408 } 409 410 if (entry->flags & XFS_ATTR_INCOMPLETE) 411 continue; /* skip incomplete entries */ 412 413 if (entry->flags & XFS_ATTR_LOCAL) { 414 xfs_attr_leaf_name_local_t *name_loc; 415 416 name_loc = xfs_attr3_leaf_name_local(leaf, i); 417 name = name_loc->nameval; 418 namelen = name_loc->namelen; 419 valuelen = be16_to_cpu(name_loc->valuelen); 420 } else { 421 xfs_attr_leaf_name_remote_t *name_rmt; 422 423 name_rmt = xfs_attr3_leaf_name_remote(leaf, i); 424 name = name_rmt->name; 425 namelen = name_rmt->namelen; 426 valuelen = be32_to_cpu(name_rmt->valuelen); 427 } 428 429 context->put_listent(context, entry->flags, 430 name, namelen, valuelen); 431 if (context->seen_enough) 432 break; 433 cursor->offset++; 434 } 435 trace_xfs_attr_list_leaf_end(context); 436 return; 437 } 438 439 /* 440 * Copy out attribute entries for attr_list(), for leaf attribute lists. 441 */ 442 STATIC int 443 xfs_attr_leaf_list(xfs_attr_list_context_t *context) 444 { 445 int error; 446 struct xfs_buf *bp; 447 448 trace_xfs_attr_leaf_list(context); 449 450 context->cursor->blkno = 0; 451 error = xfs_attr3_leaf_read(NULL, context->dp, 0, -1, &bp); 452 if (error) 453 return error; 454 455 xfs_attr3_leaf_list_int(bp, context); 456 xfs_trans_brelse(NULL, bp); 457 return 0; 458 } 459 460 int 461 xfs_attr_list_int( 462 xfs_attr_list_context_t *context) 463 { 464 int error; 465 xfs_inode_t *dp = context->dp; 466 uint lock_mode; 467 468 XFS_STATS_INC(dp->i_mount, xs_attr_list); 469 470 if (XFS_FORCED_SHUTDOWN(dp->i_mount)) 471 return -EIO; 472 473 /* 474 * Decide on what work routines to call based on the inode size. 475 */ 476 lock_mode = xfs_ilock_attr_map_shared(dp); 477 if (!xfs_inode_hasattr(dp)) { 478 error = 0; 479 } else if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) { 480 error = xfs_attr_shortform_list(context); 481 } else if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) { 482 error = xfs_attr_leaf_list(context); 483 } else { 484 error = xfs_attr_node_list(context); 485 } 486 xfs_iunlock(dp, lock_mode); 487 return error; 488 } 489 490 #define ATTR_ENTBASESIZE /* minimum bytes used by an attr */ \ 491 (((struct attrlist_ent *) 0)->a_name - (char *) 0) 492 #define ATTR_ENTSIZE(namelen) /* actual bytes used by an attr */ \ 493 ((ATTR_ENTBASESIZE + (namelen) + 1 + sizeof(u_int32_t)-1) \ 494 & ~(sizeof(u_int32_t)-1)) 495 496 /* 497 * Format an attribute and copy it out to the user's buffer. 498 * Take care to check values and protect against them changing later, 499 * we may be reading them directly out of a user buffer. 500 */ 501 STATIC void 502 xfs_attr_put_listent( 503 xfs_attr_list_context_t *context, 504 int flags, 505 unsigned char *name, 506 int namelen, 507 int valuelen) 508 { 509 struct attrlist *alist = (struct attrlist *)context->alist; 510 attrlist_ent_t *aep; 511 int arraytop; 512 513 ASSERT(!(context->flags & ATTR_KERNOVAL)); 514 ASSERT(context->count >= 0); 515 ASSERT(context->count < (ATTR_MAX_VALUELEN/8)); 516 ASSERT(context->firstu >= sizeof(*alist)); 517 ASSERT(context->firstu <= context->bufsize); 518 519 /* 520 * Only list entries in the right namespace. 521 */ 522 if (((context->flags & ATTR_SECURE) == 0) != 523 ((flags & XFS_ATTR_SECURE) == 0)) 524 return; 525 if (((context->flags & ATTR_ROOT) == 0) != 526 ((flags & XFS_ATTR_ROOT) == 0)) 527 return; 528 529 arraytop = sizeof(*alist) + 530 context->count * sizeof(alist->al_offset[0]); 531 context->firstu -= ATTR_ENTSIZE(namelen); 532 if (context->firstu < arraytop) { 533 trace_xfs_attr_list_full(context); 534 alist->al_more = 1; 535 context->seen_enough = 1; 536 return; 537 } 538 539 aep = (attrlist_ent_t *)&context->alist[context->firstu]; 540 aep->a_valuelen = valuelen; 541 memcpy(aep->a_name, name, namelen); 542 aep->a_name[namelen] = 0; 543 alist->al_offset[context->count++] = context->firstu; 544 alist->al_count = context->count; 545 trace_xfs_attr_list_add(context); 546 return; 547 } 548 549 /* 550 * Generate a list of extended attribute names and optionally 551 * also value lengths. Positive return value follows the XFS 552 * convention of being an error, zero or negative return code 553 * is the length of the buffer returned (negated), indicating 554 * success. 555 */ 556 int 557 xfs_attr_list( 558 xfs_inode_t *dp, 559 char *buffer, 560 int bufsize, 561 int flags, 562 attrlist_cursor_kern_t *cursor) 563 { 564 xfs_attr_list_context_t context; 565 struct attrlist *alist; 566 int error; 567 568 /* 569 * Validate the cursor. 570 */ 571 if (cursor->pad1 || cursor->pad2) 572 return -EINVAL; 573 if ((cursor->initted == 0) && 574 (cursor->hashval || cursor->blkno || cursor->offset)) 575 return -EINVAL; 576 577 /* 578 * Check for a properly aligned buffer. 579 */ 580 if (((long)buffer) & (sizeof(int)-1)) 581 return -EFAULT; 582 if (flags & ATTR_KERNOVAL) 583 bufsize = 0; 584 585 /* 586 * Initialize the output buffer. 587 */ 588 memset(&context, 0, sizeof(context)); 589 context.dp = dp; 590 context.cursor = cursor; 591 context.resynch = 1; 592 context.flags = flags; 593 context.alist = buffer; 594 context.bufsize = (bufsize & ~(sizeof(int)-1)); /* align */ 595 context.firstu = context.bufsize; 596 context.put_listent = xfs_attr_put_listent; 597 598 alist = (struct attrlist *)context.alist; 599 alist->al_count = 0; 600 alist->al_more = 0; 601 alist->al_offset[0] = context.bufsize; 602 603 error = xfs_attr_list_int(&context); 604 ASSERT(error <= 0); 605 return error; 606 } 607