diff options
Diffstat (limited to 'libblkid/src/superblocks/ntfs.c')
| -rw-r--r-- | libblkid/src/superblocks/ntfs.c | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/libblkid/src/superblocks/ntfs.c b/libblkid/src/superblocks/ntfs.c new file mode 100644 index 0000000..dced699 --- /dev/null +++ b/libblkid/src/superblocks/ntfs.c @@ -0,0 +1,253 @@ +/* + * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> + * Copyright (C) 2008 Karel Zak <kzak@redhat.com> + * + * This file may be redistributed under the terms of the + * GNU Lesser General Public License. + */ +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> +#include <inttypes.h> + +#include "superblocks.h" + +struct ntfs_bios_parameters { + uint16_t sector_size; /* Size of a sector in bytes. */ + uint8_t sectors_per_cluster; /* Size of a cluster in sectors. */ + uint16_t reserved_sectors; /* zero */ + uint8_t fats; /* zero */ + uint16_t root_entries; /* zero */ + uint16_t sectors; /* zero */ + uint8_t media_type; /* 0xf8 = hard disk */ + uint16_t sectors_per_fat; /* zero */ + uint16_t sectors_per_track; /* irrelevant */ + uint16_t heads; /* irrelevant */ + uint32_t hidden_sectors; /* zero */ + uint32_t large_sectors; /* zero */ +} __attribute__ ((__packed__)); + +struct ntfs_super_block { + uint8_t jump[3]; + uint8_t oem_id[8]; /* magic string */ + + struct ntfs_bios_parameters bpb; + + uint16_t unused[2]; + uint64_t number_of_sectors; + uint64_t mft_cluster_location; + uint64_t mft_mirror_cluster_location; + int8_t clusters_per_mft_record; + uint8_t reserved1[3]; + int8_t cluster_per_index_record; + uint8_t reserved2[3]; + uint64_t volume_serial; + uint32_t checksum; +} __attribute__((packed)); + +struct master_file_table_record { + uint32_t magic; + uint16_t usa_ofs; + uint16_t usa_count; + uint64_t lsn; + uint16_t sequence_number; + uint16_t link_count; + uint16_t attrs_offset; + uint16_t flags; + uint32_t bytes_in_use; + uint32_t bytes_allocated; +} __attribute__((__packed__)); + +struct file_attribute { + uint32_t type; + uint32_t len; + uint8_t non_resident; + uint8_t name_len; + uint16_t name_offset; + uint16_t flags; + uint16_t instance; + uint32_t value_len; + uint16_t value_offset; +} __attribute__((__packed__)); + +#define MFT_RECORD_VOLUME 3 +/* Windows 10 Creators edition has extended the cluster size limit to 2MB */ +#define NTFS_MAX_CLUSTER_SIZE (2 * 1024 * 1024) + +#define MFT_RECORD_ATTR_VOLUME_NAME 0x60 +#define MFT_RECORD_ATTR_END 0xffffffff + +static int __probe_ntfs(blkid_probe pr, const struct blkid_idmag *mag, int save_info) +{ + struct ntfs_super_block *ns; + struct master_file_table_record *mft; + + uint32_t sectors_per_cluster, mft_record_size; + uint16_t sector_size; + uint64_t nr_clusters, off, attr_off; + unsigned char *buf_mft; + + ns = blkid_probe_get_sb(pr, mag, struct ntfs_super_block); + if (!ns) + return errno ? -errno : 1; + + /* + * Check bios parameters block + */ + sector_size = le16_to_cpu(ns->bpb.sector_size); + + if (sector_size < 256 || sector_size > 4096) + return 1; + + switch (ns->bpb.sectors_per_cluster) { + case 1: case 2: case 4: case 8: case 16: case 32: case 64: case 128: + sectors_per_cluster = ns->bpb.sectors_per_cluster; + break; + default: + if ((ns->bpb.sectors_per_cluster < 240) + || (ns->bpb.sectors_per_cluster > 249)) + return 1; + sectors_per_cluster = 1 << (256 - ns->bpb.sectors_per_cluster); + } + + if ((uint16_t) le16_to_cpu(ns->bpb.sector_size) * + sectors_per_cluster > NTFS_MAX_CLUSTER_SIZE) + return 1; + + /* Unused fields must be zero */ + if (le16_to_cpu(ns->bpb.reserved_sectors) + || le16_to_cpu(ns->bpb.root_entries) + || le16_to_cpu(ns->bpb.sectors) + || le16_to_cpu(ns->bpb.sectors_per_fat) + || le32_to_cpu(ns->bpb.large_sectors) + || ns->bpb.fats) + return 1; + + if ((uint8_t) ns->clusters_per_mft_record < 0xe1 + || (uint8_t) ns->clusters_per_mft_record > 0xf7) { + + switch (ns->clusters_per_mft_record) { + case 1: case 2: case 4: case 8: case 16: case 32: case 64: + break; + default: + return 1; + } + } + + if (ns->clusters_per_mft_record > 0) + mft_record_size = ns->clusters_per_mft_record * + sectors_per_cluster * sector_size; + else + mft_record_size = 1 << (0 - ns->clusters_per_mft_record); + + nr_clusters = le64_to_cpu(ns->number_of_sectors) / sectors_per_cluster; + + if ((le64_to_cpu(ns->mft_cluster_location) > nr_clusters) || + (le64_to_cpu(ns->mft_mirror_cluster_location) > nr_clusters)) + return 1; + + + off = le64_to_cpu(ns->mft_cluster_location) * sector_size * + sectors_per_cluster; + + DBG(LOWPROBE, ul_debug("NTFS: sector_size=%"PRIu16", mft_record_size=%"PRIu32", " + "sectors_per_cluster=%"PRIu32", nr_clusters=%"PRIu64" " + "cluster_offset=%"PRIu64"", + sector_size, mft_record_size, + sectors_per_cluster, nr_clusters, + off)); + + if (mft_record_size < 4) + return 1; + + buf_mft = blkid_probe_get_buffer(pr, off, mft_record_size); + if (!buf_mft) + return errno ? -errno : 1; + + if (memcmp(buf_mft, "FILE", 4) != 0) + return 1; + + off += MFT_RECORD_VOLUME * mft_record_size; + + buf_mft = blkid_probe_get_buffer(pr, off, mft_record_size); + if (!buf_mft) + return errno ? -errno : 1; + + if (memcmp(buf_mft, "FILE", 4) != 0) + return 1; + + /* return if caller does not care about UUID and LABEL */ + if (!save_info) + return 0; + + mft = (struct master_file_table_record *) buf_mft; + attr_off = le16_to_cpu(mft->attrs_offset); + + while (attr_off + sizeof(struct file_attribute) <= mft_record_size && + attr_off <= le32_to_cpu(mft->bytes_allocated)) { + + uint32_t attr_len; + struct file_attribute *attr; + + attr = (struct file_attribute *) (buf_mft + attr_off); + attr_len = le32_to_cpu(attr->len); + if (!attr_len) + break; + + if (le32_to_cpu(attr->type) == (uint32_t) MFT_RECORD_ATTR_END) + break; + if (le32_to_cpu(attr->type) == (uint32_t) MFT_RECORD_ATTR_VOLUME_NAME) { + unsigned int val_off = le16_to_cpu(attr->value_offset); + unsigned int val_len = le32_to_cpu(attr->value_len); + unsigned char *val = ((uint8_t *) attr) + val_off; + + if (attr_off + val_off + val_len <= mft_record_size) + blkid_probe_set_utf8label(pr, val, val_len, + UL_ENCODE_UTF16LE); + break; + } + + attr_off += attr_len; + } + + blkid_probe_set_block_size(pr, sector_size); + + blkid_probe_sprintf_uuid(pr, + (unsigned char *) &ns->volume_serial, + sizeof(ns->volume_serial), + "%016" PRIX64, le64_to_cpu(ns->volume_serial)); + return 0; +} + +static int probe_ntfs(blkid_probe pr, const struct blkid_idmag *mag) +{ + return __probe_ntfs(pr, mag, 1); +} + +int blkid_probe_is_ntfs(blkid_probe pr) +{ + const struct blkid_idmag *mag = NULL; + int rc; + + rc = blkid_probe_get_idmag(pr, &ntfs_idinfo, NULL, &mag); + if (rc < 0) + return rc; /* error */ + if (rc != BLKID_PROBE_OK || !mag) + return 0; + + return __probe_ntfs(pr, mag, 0) == 0 ? 1 : 0; +} + +const struct blkid_idinfo ntfs_idinfo = +{ + .name = "ntfs", + .usage = BLKID_USAGE_FILESYSTEM, + .probefunc = probe_ntfs, + .magics = + { + { .magic = "NTFS ", .len = 8, .sboff = 3 }, + { NULL } + } +}; + |