crypto.c (17398957aa0a05ef62535060b41d103590dcc533) crypto.c (dd2a3b7ad98f8482cae481cad89dfed5eee48365)
1/**
2 * eCryptfs: Linux filesystem encryption layer
3 *
4 * Copyright (C) 1997-2004 Erez Zadok
5 * Copyright (C) 2001-2004 Stony Brook University
1/**
2 * eCryptfs: Linux filesystem encryption layer
3 *
4 * Copyright (C) 1997-2004 Erez Zadok
5 * Copyright (C) 2001-2004 Stony Brook University
6 * Copyright (C) 2004-2006 International Business Machines Corp.
6 * Copyright (C) 2004-2007 International Business Machines Corp.
7 * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
8 * Michael C. Thompson <mcthomps@us.ibm.com>
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation; either version 2 of the
13 * License, or (at your option) any later version.
14 *

--- 843 unchanged lines hidden (view full) ---

858 crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE;
859 set_extent_mask_and_shift(crypt_stat);
860 crypt_stat->iv_bytes = ECRYPTFS_DEFAULT_IV_BYTES;
861 if (PAGE_CACHE_SIZE <= ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE) {
862 crypt_stat->header_extent_size =
863 ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
864 } else
865 crypt_stat->header_extent_size = PAGE_CACHE_SIZE;
7 * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
8 * Michael C. Thompson <mcthomps@us.ibm.com>
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation; either version 2 of the
13 * License, or (at your option) any later version.
14 *

--- 843 unchanged lines hidden (view full) ---

858 crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE;
859 set_extent_mask_and_shift(crypt_stat);
860 crypt_stat->iv_bytes = ECRYPTFS_DEFAULT_IV_BYTES;
861 if (PAGE_CACHE_SIZE <= ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE) {
862 crypt_stat->header_extent_size =
863 ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
864 } else
865 crypt_stat->header_extent_size = PAGE_CACHE_SIZE;
866 crypt_stat->num_header_extents_at_front = 1;
866 if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
867 crypt_stat->num_header_extents_at_front = 0;
868 else
869 crypt_stat->num_header_extents_at_front = 1;
867}
868
869/**
870 * ecryptfs_compute_root_iv
871 * @crypt_stats
872 *
873 * On error, sets the root IV to all 0's.
874 */

--- 141 unchanged lines hidden (view full) ---

1016}
1017
1018/**
1019 * contains_ecryptfs_marker - check for the ecryptfs marker
1020 * @data: The data block in which to check
1021 *
1022 * Returns one if marker found; zero if not found
1023 */
870}
871
872/**
873 * ecryptfs_compute_root_iv
874 * @crypt_stats
875 *
876 * On error, sets the root IV to all 0's.
877 */

--- 141 unchanged lines hidden (view full) ---

1019}
1020
1021/**
1022 * contains_ecryptfs_marker - check for the ecryptfs marker
1023 * @data: The data block in which to check
1024 *
1025 * Returns one if marker found; zero if not found
1026 */
1024int contains_ecryptfs_marker(char *data)
1027static int contains_ecryptfs_marker(char *data)
1025{
1026 u32 m_1, m_2;
1027
1028 memcpy(&m_1, data, 4);
1029 m_1 = be32_to_cpu(m_1);
1030 memcpy(&m_2, (data + 4), 4);
1031 m_2 = be32_to_cpu(m_2);
1032 if ((m_1 ^ MAGIC_ECRYPTFS_MARKER) == m_2)

--- 9 unchanged lines hidden (view full) ---

1042struct ecryptfs_flag_map_elem {
1043 u32 file_flag;
1044 u32 local_flag;
1045};
1046
1047/* Add support for additional flags by adding elements here. */
1048static struct ecryptfs_flag_map_elem ecryptfs_flag_map[] = {
1049 {0x00000001, ECRYPTFS_ENABLE_HMAC},
1028{
1029 u32 m_1, m_2;
1030
1031 memcpy(&m_1, data, 4);
1032 m_1 = be32_to_cpu(m_1);
1033 memcpy(&m_2, (data + 4), 4);
1034 m_2 = be32_to_cpu(m_2);
1035 if ((m_1 ^ MAGIC_ECRYPTFS_MARKER) == m_2)

--- 9 unchanged lines hidden (view full) ---

1045struct ecryptfs_flag_map_elem {
1046 u32 file_flag;
1047 u32 local_flag;
1048};
1049
1050/* Add support for additional flags by adding elements here. */
1051static struct ecryptfs_flag_map_elem ecryptfs_flag_map[] = {
1052 {0x00000001, ECRYPTFS_ENABLE_HMAC},
1050 {0x00000002, ECRYPTFS_ENCRYPTED}
1053 {0x00000002, ECRYPTFS_ENCRYPTED},
1054 {0x00000004, ECRYPTFS_METADATA_IN_XATTR}
1051};
1052
1053/**
1054 * ecryptfs_process_flags
1055 * @crypt_stat
1056 * @page_virt: Source data to be parsed
1057 * @bytes_read: Updated with the number of bytes read
1058 *

--- 143 unchanged lines hidden (view full) ---

1202/**
1203 * ecryptfs_read_header_region
1204 * @data
1205 * @dentry
1206 * @nd
1207 *
1208 * Returns zero on success; non-zero otherwise
1209 */
1055};
1056
1057/**
1058 * ecryptfs_process_flags
1059 * @crypt_stat
1060 * @page_virt: Source data to be parsed
1061 * @bytes_read: Updated with the number of bytes read
1062 *

--- 143 unchanged lines hidden (view full) ---

1206/**
1207 * ecryptfs_read_header_region
1208 * @data
1209 * @dentry
1210 * @nd
1211 *
1212 * Returns zero on success; non-zero otherwise
1213 */
1210int ecryptfs_read_header_region(char *data, struct dentry *dentry,
1211 struct vfsmount *mnt)
1214static int ecryptfs_read_header_region(char *data, struct dentry *dentry,
1215 struct vfsmount *mnt)
1212{
1213 struct file *lower_file;
1214 mm_segment_t oldfs;
1215 int rc;
1216
1217 if ((rc = ecryptfs_open_lower_file(&lower_file, dentry, mnt,
1218 O_RDONLY))) {
1219 printk(KERN_ERR

--- 12 unchanged lines hidden (view full) ---

1232 printk(KERN_ERR "Error closing lower_file\n");
1233 goto out;
1234 }
1235 rc = 0;
1236out:
1237 return rc;
1238}
1239
1216{
1217 struct file *lower_file;
1218 mm_segment_t oldfs;
1219 int rc;
1220
1221 if ((rc = ecryptfs_open_lower_file(&lower_file, dentry, mnt,
1222 O_RDONLY))) {
1223 printk(KERN_ERR

--- 12 unchanged lines hidden (view full) ---

1236 printk(KERN_ERR "Error closing lower_file\n");
1237 goto out;
1238 }
1239 rc = 0;
1240out:
1241 return rc;
1242}
1243
1244int ecryptfs_read_and_validate_header_region(char *data, struct dentry *dentry,
1245 struct vfsmount *mnt)
1246{
1247 int rc;
1248
1249 rc = ecryptfs_read_header_region(data, dentry, mnt);
1250 if (rc)
1251 goto out;
1252 if (!contains_ecryptfs_marker(data + ECRYPTFS_FILE_SIZE_BYTES))
1253 rc = -EINVAL;
1254out:
1255 return rc;
1256}
1257
1258
1240static void
1241write_header_metadata(char *virt, struct ecryptfs_crypt_stat *crypt_stat,
1242 size_t *written)
1243{
1244 u32 header_extent_size;
1245 u16 num_header_extents_at_front;
1246
1247 header_extent_size = (u32)crypt_stat->header_extent_size;

--- 35 unchanged lines hidden (view full) ---

1283 * Data Extent 0:
1284 * Lower data (CBC encrypted)
1285 * Data Extent 1:
1286 * Lower data (CBC encrypted)
1287 * ...
1288 *
1289 * Returns zero on success
1290 */
1259static void
1260write_header_metadata(char *virt, struct ecryptfs_crypt_stat *crypt_stat,
1261 size_t *written)
1262{
1263 u32 header_extent_size;
1264 u16 num_header_extents_at_front;
1265
1266 header_extent_size = (u32)crypt_stat->header_extent_size;

--- 35 unchanged lines hidden (view full) ---

1302 * Data Extent 0:
1303 * Lower data (CBC encrypted)
1304 * Data Extent 1:
1305 * Lower data (CBC encrypted)
1306 * ...
1307 *
1308 * Returns zero on success
1309 */
1291int ecryptfs_write_headers_virt(char *page_virt,
1292 struct ecryptfs_crypt_stat *crypt_stat,
1293 struct dentry *ecryptfs_dentry)
1310static int ecryptfs_write_headers_virt(char *page_virt, size_t *size,
1311 struct ecryptfs_crypt_stat *crypt_stat,
1312 struct dentry *ecryptfs_dentry)
1294{
1295 int rc;
1296 size_t written;
1297 size_t offset;
1298
1299 offset = ECRYPTFS_FILE_SIZE_BYTES;
1300 write_ecryptfs_marker((page_virt + offset), &written);
1301 offset += written;
1302 write_ecryptfs_flags((page_virt + offset), crypt_stat, &written);
1303 offset += written;
1304 write_header_metadata((page_virt + offset), crypt_stat, &written);
1305 offset += written;
1306 rc = ecryptfs_generate_key_packet_set((page_virt + offset), crypt_stat,
1307 ecryptfs_dentry, &written,
1308 PAGE_CACHE_SIZE - offset);
1309 if (rc)
1310 ecryptfs_printk(KERN_WARNING, "Error generating key packet "
1311 "set; rc = [%d]\n", rc);
1313{
1314 int rc;
1315 size_t written;
1316 size_t offset;
1317
1318 offset = ECRYPTFS_FILE_SIZE_BYTES;
1319 write_ecryptfs_marker((page_virt + offset), &written);
1320 offset += written;
1321 write_ecryptfs_flags((page_virt + offset), crypt_stat, &written);
1322 offset += written;
1323 write_header_metadata((page_virt + offset), crypt_stat, &written);
1324 offset += written;
1325 rc = ecryptfs_generate_key_packet_set((page_virt + offset), crypt_stat,
1326 ecryptfs_dentry, &written,
1327 PAGE_CACHE_SIZE - offset);
1328 if (rc)
1329 ecryptfs_printk(KERN_WARNING, "Error generating key packet "
1330 "set; rc = [%d]\n", rc);
1331 if (size) {
1332 offset += written;
1333 *size = offset;
1334 }
1312 return rc;
1313}
1314
1335 return rc;
1336}
1337
1338static int ecryptfs_write_metadata_to_contents(struct ecryptfs_crypt_stat *crypt_stat,
1339 struct file *lower_file,
1340 char *page_virt)
1341{
1342 mm_segment_t oldfs;
1343 int current_header_page;
1344 int header_pages;
1345
1346 lower_file->f_pos = 0;
1347 oldfs = get_fs();
1348 set_fs(get_ds());
1349 lower_file->f_op->write(lower_file, (char __user *)page_virt,
1350 PAGE_CACHE_SIZE, &lower_file->f_pos);
1351 header_pages = ((crypt_stat->header_extent_size
1352 * crypt_stat->num_header_extents_at_front)
1353 / PAGE_CACHE_SIZE);
1354 memset(page_virt, 0, PAGE_CACHE_SIZE);
1355 current_header_page = 1;
1356 while (current_header_page < header_pages) {
1357 lower_file->f_op->write(lower_file, (char __user *)page_virt,
1358 PAGE_CACHE_SIZE, &lower_file->f_pos);
1359 current_header_page++;
1360 }
1361 set_fs(oldfs);
1362 return 0;
1363}
1364
1365static int ecryptfs_write_metadata_to_xattr(struct dentry *ecryptfs_dentry,
1366 struct ecryptfs_crypt_stat *crypt_stat,
1367 char *page_virt, size_t size)
1368{
1369 int rc;
1370
1371 rc = ecryptfs_setxattr(ecryptfs_dentry, ECRYPTFS_XATTR_NAME, page_virt,
1372 size, 0);
1373 return rc;
1374}
1375
1315/**
1376/**
1316 * ecryptfs_write_headers
1377 * ecryptfs_write_metadata
1317 * @lower_file: The lower file struct, which was returned from dentry_open
1318 *
1319 * Write the file headers out. This will likely involve a userspace
1320 * callout, in which the session key is encrypted with one or more
1321 * public keys and/or the passphrase necessary to do the encryption is
1322 * retrieved via a prompt. Exactly what happens at this point should
1323 * be policy-dependent.
1324 *
1325 * Returns zero on success; non-zero on error
1326 */
1378 * @lower_file: The lower file struct, which was returned from dentry_open
1379 *
1380 * Write the file headers out. This will likely involve a userspace
1381 * callout, in which the session key is encrypted with one or more
1382 * public keys and/or the passphrase necessary to do the encryption is
1383 * retrieved via a prompt. Exactly what happens at this point should
1384 * be policy-dependent.
1385 *
1386 * Returns zero on success; non-zero on error
1387 */
1327int ecryptfs_write_headers(struct dentry *ecryptfs_dentry,
1328 struct file *lower_file)
1388int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry,
1389 struct file *lower_file)
1329{
1390{
1330 mm_segment_t oldfs;
1331 struct ecryptfs_crypt_stat *crypt_stat;
1332 char *page_virt;
1391 struct ecryptfs_crypt_stat *crypt_stat;
1392 char *page_virt;
1333 int current_header_page;
1334 int header_pages;
1393 size_t size;
1335 int rc = 0;
1336
1337 crypt_stat = &ecryptfs_inode_to_private(
1338 ecryptfs_dentry->d_inode)->crypt_stat;
1339 if (likely(ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
1340 ECRYPTFS_ENCRYPTED))) {
1341 if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
1342 ECRYPTFS_KEY_VALID)) {

--- 10 unchanged lines hidden (view full) ---

1353 }
1354 /* Released in this function */
1355 page_virt = kmem_cache_zalloc(ecryptfs_header_cache_0, GFP_USER);
1356 if (!page_virt) {
1357 ecryptfs_printk(KERN_ERR, "Out of memory\n");
1358 rc = -ENOMEM;
1359 goto out;
1360 }
1394 int rc = 0;
1395
1396 crypt_stat = &ecryptfs_inode_to_private(
1397 ecryptfs_dentry->d_inode)->crypt_stat;
1398 if (likely(ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
1399 ECRYPTFS_ENCRYPTED))) {
1400 if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
1401 ECRYPTFS_KEY_VALID)) {

--- 10 unchanged lines hidden (view full) ---

1412 }
1413 /* Released in this function */
1414 page_virt = kmem_cache_zalloc(ecryptfs_header_cache_0, GFP_USER);
1415 if (!page_virt) {
1416 ecryptfs_printk(KERN_ERR, "Out of memory\n");
1417 rc = -ENOMEM;
1418 goto out;
1419 }
1361
1362 rc = ecryptfs_write_headers_virt(page_virt, crypt_stat,
1363 ecryptfs_dentry);
1420 rc = ecryptfs_write_headers_virt(page_virt, &size, crypt_stat,
1421 ecryptfs_dentry);
1364 if (unlikely(rc)) {
1365 ecryptfs_printk(KERN_ERR, "Error whilst writing headers\n");
1366 memset(page_virt, 0, PAGE_CACHE_SIZE);
1367 goto out_free;
1368 }
1422 if (unlikely(rc)) {
1423 ecryptfs_printk(KERN_ERR, "Error whilst writing headers\n");
1424 memset(page_virt, 0, PAGE_CACHE_SIZE);
1425 goto out_free;
1426 }
1369 ecryptfs_printk(KERN_DEBUG,
1370 "Writing key packet set to underlying file\n");
1371 lower_file->f_pos = 0;
1372 oldfs = get_fs();
1373 set_fs(get_ds());
1374 ecryptfs_printk(KERN_DEBUG, "Calling lower_file->f_op->"
1375 "write() w/ header page; lower_file->f_pos = "
1376 "[0x%.16x]\n", lower_file->f_pos);
1377 lower_file->f_op->write(lower_file, (char __user *)page_virt,
1378 PAGE_CACHE_SIZE, &lower_file->f_pos);
1379 header_pages = ((crypt_stat->header_extent_size
1380 * crypt_stat->num_header_extents_at_front)
1381 / PAGE_CACHE_SIZE);
1382 memset(page_virt, 0, PAGE_CACHE_SIZE);
1383 current_header_page = 1;
1384 while (current_header_page < header_pages) {
1385 ecryptfs_printk(KERN_DEBUG, "Calling lower_file->f_op->"
1386 "write() w/ zero'd page; lower_file->f_pos = "
1387 "[0x%.16x]\n", lower_file->f_pos);
1388 lower_file->f_op->write(lower_file, (char __user *)page_virt,
1389 PAGE_CACHE_SIZE, &lower_file->f_pos);
1390 current_header_page++;
1427 if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
1428 rc = ecryptfs_write_metadata_to_xattr(ecryptfs_dentry,
1429 crypt_stat, page_virt,
1430 size);
1431 else
1432 rc = ecryptfs_write_metadata_to_contents(crypt_stat, lower_file,
1433 page_virt);
1434 if (rc) {
1435 printk(KERN_ERR "Error writing metadata out to lower file; "
1436 "rc = [%d]\n", rc);
1437 goto out_free;
1391 }
1438 }
1392 set_fs(oldfs);
1393 ecryptfs_printk(KERN_DEBUG,
1394 "Done writing key packet set to underlying file.\n");
1395out_free:
1396 kmem_cache_free(ecryptfs_header_cache_0, page_virt);
1397out:
1398 return rc;
1399}
1400
1439out_free:
1440 kmem_cache_free(ecryptfs_header_cache_0, page_virt);
1441out:
1442 return rc;
1443}
1444
1445#define ECRYPTFS_DONT_VALIDATE_HEADER_SIZE 0
1446#define ECRYPTFS_VALIDATE_HEADER_SIZE 1
1401static int parse_header_metadata(struct ecryptfs_crypt_stat *crypt_stat,
1447static int parse_header_metadata(struct ecryptfs_crypt_stat *crypt_stat,
1402 char *virt, int *bytes_read)
1448 char *virt, int *bytes_read,
1449 int validate_header_size)
1403{
1404 int rc = 0;
1405 u32 header_extent_size;
1406 u16 num_header_extents_at_front;
1407
1408 memcpy(&header_extent_size, virt, 4);
1409 header_extent_size = be32_to_cpu(header_extent_size);
1410 virt += 4;
1411 memcpy(&num_header_extents_at_front, virt, 2);
1412 num_header_extents_at_front = be16_to_cpu(num_header_extents_at_front);
1413 crypt_stat->header_extent_size = (int)header_extent_size;
1414 crypt_stat->num_header_extents_at_front =
1415 (int)num_header_extents_at_front;
1416 (*bytes_read) = 6;
1450{
1451 int rc = 0;
1452 u32 header_extent_size;
1453 u16 num_header_extents_at_front;
1454
1455 memcpy(&header_extent_size, virt, 4);
1456 header_extent_size = be32_to_cpu(header_extent_size);
1457 virt += 4;
1458 memcpy(&num_header_extents_at_front, virt, 2);
1459 num_header_extents_at_front = be16_to_cpu(num_header_extents_at_front);
1460 crypt_stat->header_extent_size = (int)header_extent_size;
1461 crypt_stat->num_header_extents_at_front =
1462 (int)num_header_extents_at_front;
1463 (*bytes_read) = 6;
1417 if ((crypt_stat->header_extent_size
1418 * crypt_stat->num_header_extents_at_front)
1419 < ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE) {
1464 if ((validate_header_size == ECRYPTFS_VALIDATE_HEADER_SIZE)
1465 && ((crypt_stat->header_extent_size
1466 * crypt_stat->num_header_extents_at_front)
1467 < ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)) {
1420 rc = -EINVAL;
1421 ecryptfs_printk(KERN_WARNING, "Invalid header extent size: "
1422 "[%d]\n", crypt_stat->header_extent_size);
1423 }
1424 return rc;
1425}
1426
1427/**

--- 14 unchanged lines hidden (view full) ---

1442 *
1443 * Read/parse the header data. The header format is detailed in the
1444 * comment block for the ecryptfs_write_headers_virt() function.
1445 *
1446 * Returns zero on success
1447 */
1448static int ecryptfs_read_headers_virt(char *page_virt,
1449 struct ecryptfs_crypt_stat *crypt_stat,
1468 rc = -EINVAL;
1469 ecryptfs_printk(KERN_WARNING, "Invalid header extent size: "
1470 "[%d]\n", crypt_stat->header_extent_size);
1471 }
1472 return rc;
1473}
1474
1475/**

--- 14 unchanged lines hidden (view full) ---

1490 *
1491 * Read/parse the header data. The header format is detailed in the
1492 * comment block for the ecryptfs_write_headers_virt() function.
1493 *
1494 * Returns zero on success
1495 */
1496static int ecryptfs_read_headers_virt(char *page_virt,
1497 struct ecryptfs_crypt_stat *crypt_stat,
1450 struct dentry *ecryptfs_dentry)
1498 struct dentry *ecryptfs_dentry,
1499 int validate_header_size)
1451{
1452 int rc = 0;
1453 int offset;
1454 int bytes_read;
1455
1456 ecryptfs_set_default_sizes(crypt_stat);
1457 crypt_stat->mount_crypt_stat = &ecryptfs_superblock_to_private(
1458 ecryptfs_dentry->d_sb)->mount_crypt_stat;

--- 17 unchanged lines hidden (view full) ---

1476 crypt_stat->file_version,
1477 ECRYPTFS_SUPPORTED_FILE_VERSION);
1478 rc = -EINVAL;
1479 goto out;
1480 }
1481 offset += bytes_read;
1482 if (crypt_stat->file_version >= 1) {
1483 rc = parse_header_metadata(crypt_stat, (page_virt + offset),
1500{
1501 int rc = 0;
1502 int offset;
1503 int bytes_read;
1504
1505 ecryptfs_set_default_sizes(crypt_stat);
1506 crypt_stat->mount_crypt_stat = &ecryptfs_superblock_to_private(
1507 ecryptfs_dentry->d_sb)->mount_crypt_stat;

--- 17 unchanged lines hidden (view full) ---

1525 crypt_stat->file_version,
1526 ECRYPTFS_SUPPORTED_FILE_VERSION);
1527 rc = -EINVAL;
1528 goto out;
1529 }
1530 offset += bytes_read;
1531 if (crypt_stat->file_version >= 1) {
1532 rc = parse_header_metadata(crypt_stat, (page_virt + offset),
1484 &bytes_read);
1533 &bytes_read, validate_header_size);
1485 if (rc) {
1486 ecryptfs_printk(KERN_WARNING, "Error reading header "
1487 "metadata; rc = [%d]\n", rc);
1488 }
1489 offset += bytes_read;
1490 } else
1491 set_default_header_data(crypt_stat);
1492 rc = ecryptfs_parse_packet_set(crypt_stat, (page_virt + offset),
1493 ecryptfs_dentry);
1494out:
1495 return rc;
1496}
1497
1498/**
1534 if (rc) {
1535 ecryptfs_printk(KERN_WARNING, "Error reading header "
1536 "metadata; rc = [%d]\n", rc);
1537 }
1538 offset += bytes_read;
1539 } else
1540 set_default_header_data(crypt_stat);
1541 rc = ecryptfs_parse_packet_set(crypt_stat, (page_virt + offset),
1542 ecryptfs_dentry);
1543out:
1544 return rc;
1545}
1546
1547/**
1499 * ecryptfs_read_headers
1548 * ecryptfs_read_xattr_region
1500 *
1549 *
1550 * Attempts to read the crypto metadata from the extended attribute
1551 * region of the lower file.
1552 */
1553int ecryptfs_read_xattr_region(char *page_virt, struct dentry *ecryptfs_dentry)
1554{
1555 ssize_t size;
1556 int rc = 0;
1557
1558 size = ecryptfs_getxattr(ecryptfs_dentry, ECRYPTFS_XATTR_NAME,
1559 page_virt, ECRYPTFS_DEFAULT_EXTENT_SIZE);
1560 if (size < 0) {
1561 printk(KERN_DEBUG "Error attempting to read the [%s] "
1562 "xattr from the lower file; return value = [%zd]\n",
1563 ECRYPTFS_XATTR_NAME, size);
1564 rc = -EINVAL;
1565 goto out;
1566 }
1567out:
1568 return rc;
1569}
1570
1571int ecryptfs_read_and_validate_xattr_region(char *page_virt,
1572 struct dentry *ecryptfs_dentry)
1573{
1574 int rc;
1575
1576 rc = ecryptfs_read_xattr_region(page_virt, ecryptfs_dentry);
1577 if (rc)
1578 goto out;
1579 if (!contains_ecryptfs_marker(page_virt + ECRYPTFS_FILE_SIZE_BYTES)) {
1580 printk(KERN_WARNING "Valid data found in [%s] xattr, but "
1581 "the marker is invalid\n", ECRYPTFS_XATTR_NAME);
1582 rc = -EINVAL;
1583 }
1584out:
1585 return rc;
1586}
1587
1588/**
1589 * ecryptfs_read_metadata
1590 *
1591 * Common entry point for reading file metadata. From here, we could
1592 * retrieve the header information from the header region of the file,
1593 * the xattr region of the file, or some other repostory that is
1594 * stored separately from the file itself. The current implementation
1595 * supports retrieving the metadata information from the file contents
1596 * and from the xattr region.
1597 *
1501 * Returns zero if valid headers found and parsed; non-zero otherwise
1502 */
1598 * Returns zero if valid headers found and parsed; non-zero otherwise
1599 */
1503int ecryptfs_read_headers(struct dentry *ecryptfs_dentry,
1504 struct file *lower_file)
1600int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry,
1601 struct file *lower_file)
1505{
1506 int rc = 0;
1507 char *page_virt = NULL;
1508 mm_segment_t oldfs;
1509 ssize_t bytes_read;
1510 struct ecryptfs_crypt_stat *crypt_stat =
1511 &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
1512

--- 12 unchanged lines hidden (view full) ---

1525 ECRYPTFS_DEFAULT_EXTENT_SIZE,
1526 &lower_file->f_pos);
1527 set_fs(oldfs);
1528 if (bytes_read != ECRYPTFS_DEFAULT_EXTENT_SIZE) {
1529 rc = -EINVAL;
1530 goto out;
1531 }
1532 rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
1602{
1603 int rc = 0;
1604 char *page_virt = NULL;
1605 mm_segment_t oldfs;
1606 ssize_t bytes_read;
1607 struct ecryptfs_crypt_stat *crypt_stat =
1608 &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
1609

--- 12 unchanged lines hidden (view full) ---

1622 ECRYPTFS_DEFAULT_EXTENT_SIZE,
1623 &lower_file->f_pos);
1624 set_fs(oldfs);
1625 if (bytes_read != ECRYPTFS_DEFAULT_EXTENT_SIZE) {
1626 rc = -EINVAL;
1627 goto out;
1628 }
1629 rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
1533 ecryptfs_dentry);
1630 ecryptfs_dentry,
1631 ECRYPTFS_VALIDATE_HEADER_SIZE);
1534 if (rc) {
1632 if (rc) {
1535 ecryptfs_printk(KERN_DEBUG, "Valid eCryptfs headers not "
1536 "found\n");
1537 rc = -EINVAL;
1633 rc = ecryptfs_read_xattr_region(page_virt,
1634 ecryptfs_dentry);
1635 if (rc) {
1636 printk(KERN_DEBUG "Valid eCryptfs headers not found in "
1637 "file header region or xattr region\n");
1638 rc = -EINVAL;
1639 goto out;
1640 }
1641 rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
1642 ecryptfs_dentry,
1643 ECRYPTFS_DONT_VALIDATE_HEADER_SIZE);
1644 if (rc) {
1645 printk(KERN_DEBUG "Valid eCryptfs headers not found in "
1646 "file xattr region either\n");
1647 rc = -EINVAL;
1648 }
1649 if (crypt_stat->mount_crypt_stat->flags
1650 & ECRYPTFS_XATTR_METADATA_ENABLED) {
1651 crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
1652 } else {
1653 printk(KERN_WARNING "Attempt to access file with "
1654 "crypto metadata only in the extended attribute "
1655 "region, but eCryptfs was mounted without "
1656 "xattr support enabled. eCryptfs will not treat "
1657 "this like an encrypted file.\n");
1658 rc = -EINVAL;
1659 }
1538 }
1539out:
1540 if (page_virt) {
1541 memset(page_virt, 0, PAGE_CACHE_SIZE);
1542 kmem_cache_free(ecryptfs_header_cache_1, page_virt);
1543 }
1544 return rc;
1545}

--- 147 unchanged lines hidden --- 		1660 }
1661out:
1662 if (page_virt) {
1663 memset(page_virt, 0, PAGE_CACHE_SIZE);
1664 kmem_cache_free(ecryptfs_header_cache_1, page_virt);
1665 }
1666 return rc;
1667}

--- 147 unchanged lines hidden ---