diff options
Diffstat (limited to 'util-linux/volume_id/ntfs.c')
| -rw-r--r-- | util-linux/volume_id/ntfs.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/util-linux/volume_id/ntfs.c b/util-linux/volume_id/ntfs.c new file mode 100644 index 0000000..cbd5d5b --- /dev/null +++ b/util-linux/volume_id/ntfs.c @@ -0,0 +1,193 @@ +/* + * volume_id - reads filesystem label and uuid + * + * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include "volume_id_internal.h" + +struct ntfs_super_block { + uint8_t jump[3]; + uint8_t oem_id[8]; + uint16_t bytes_per_sector; + uint8_t sectors_per_cluster; + uint16_t reserved_sectors; + uint8_t fats; + uint16_t root_entries; + uint16_t sectors; + uint8_t media_type; + uint16_t sectors_per_fat; + uint16_t sectors_per_track; + uint16_t heads; + uint32_t hidden_sectors; + uint32_t large_sectors; + uint16_t unused[2]; + uint64_t number_of_sectors; + uint64_t mft_cluster_location; + uint64_t mft_mirror_cluster_location; + int8_t cluster_per_mft_record; + uint8_t reserved1[3]; + int8_t cluster_per_index_record; + uint8_t reserved2[3]; + uint8_t volume_serial[8]; + uint16_t checksum; +} __attribute__((__packed__)); + +struct master_file_table_record { + uint8_t magic[4]; + 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__)); + +struct volume_info { + uint64_t reserved; + uint8_t major_ver; + uint8_t minor_ver; +} __attribute__((__packed__)); + +#define MFT_RECORD_VOLUME 3 +#define MFT_RECORD_ATTR_VOLUME_NAME 0x60 +#define MFT_RECORD_ATTR_VOLUME_INFO 0x70 +#define MFT_RECORD_ATTR_OBJECT_ID 0x40 +#define MFT_RECORD_ATTR_END 0xffffffffu + +int volume_id_probe_ntfs(struct volume_id *id, uint64_t off) +{ + unsigned sector_size; + unsigned cluster_size; + uint64_t mft_cluster; + uint64_t mft_off; + unsigned mft_record_size; + unsigned attr_type; + unsigned attr_off; + unsigned attr_len; + unsigned val_off; + unsigned val_len; + struct master_file_table_record *mftr; + struct ntfs_super_block *ns; + const uint8_t *buf; + const uint8_t *val; + + dbg("probing at offset 0x%llx", (unsigned long long) off); + + ns = volume_id_get_buffer(id, off, 0x200); + if (ns == NULL) + return -1; + + if (memcmp(ns->oem_id, "NTFS", 4) != 0) + return -1; + + volume_id_set_uuid(id, ns->volume_serial, UUID_NTFS); + + sector_size = le16_to_cpu(ns->bytes_per_sector); + cluster_size = ns->sectors_per_cluster * sector_size; + mft_cluster = le64_to_cpu(ns->mft_cluster_location); + mft_off = mft_cluster * cluster_size; + + if (ns->cluster_per_mft_record < 0) + /* size = -log2(mft_record_size); normally 1024 Bytes */ + mft_record_size = 1 << -ns->cluster_per_mft_record; + else + mft_record_size = ns->cluster_per_mft_record * cluster_size; + + dbg("sectorsize 0x%x", sector_size); + dbg("clustersize 0x%x", cluster_size); + dbg("mftcluster %llu", (unsigned long long) mft_cluster); + dbg("mftoffset 0x%llx", (unsigned long long) mft_off); + dbg("cluster per mft_record %i", ns->cluster_per_mft_record); + dbg("mft record size %i", mft_record_size); + + buf = volume_id_get_buffer(id, off + mft_off + (MFT_RECORD_VOLUME * mft_record_size), + mft_record_size); + if (buf == NULL) + goto found; + + mftr = (struct master_file_table_record*) buf; + + dbg("mftr->magic '%c%c%c%c'", mftr->magic[0], mftr->magic[1], mftr->magic[2], mftr->magic[3]); + if (memcmp(mftr->magic, "FILE", 4) != 0) + goto found; + + attr_off = le16_to_cpu(mftr->attrs_offset); + dbg("file $Volume's attributes are at offset %i", attr_off); + + while (1) { + struct file_attribute *attr; + + attr = (struct file_attribute*) &buf[attr_off]; + attr_type = le32_to_cpu(attr->type); + attr_len = le16_to_cpu(attr->len); + val_off = le16_to_cpu(attr->value_offset); + val_len = le32_to_cpu(attr->value_len); + attr_off += attr_len; + + if (attr_len == 0) + break; + + if (attr_off >= mft_record_size) + break; + + if (attr_type == MFT_RECORD_ATTR_END) + break; + + dbg("found attribute type 0x%x, len %i, at offset %i", + attr_type, attr_len, attr_off); + + if (attr_type == MFT_RECORD_ATTR_VOLUME_INFO) { + struct volume_info *info; + dbg("found info, len %i", val_len); + info = (struct volume_info*) (((uint8_t *) attr) + val_off); + snprintf(id->type_version, sizeof(id->type_version)-1, + "%u.%u", info->major_ver, info->minor_ver); + } + + if (attr_type == MFT_RECORD_ATTR_VOLUME_NAME) { + dbg("found label, len %i", val_len); + if (val_len > VOLUME_ID_LABEL_SIZE) + val_len = VOLUME_ID_LABEL_SIZE; + + val = ((uint8_t *) attr) + val_off; + volume_id_set_label_raw(id, val, val_len); + volume_id_set_label_unicode16(id, val, LE, val_len); + } + } + + found: + volume_id_set_usage(id, VOLUME_ID_FILESYSTEM); + id->type = "ntfs"; + + return 0; +} |