Apparatus and method for protecting system data on computer hard-disk
View Patent ↗An apparatus and method for protecting and recovering system data stored in a computer hard disk from corruption that may occur due to malicious or accidental operation during use of a computer are provided. According to the apparatus and method, not an entire system area but a part needing protection in the system area is selectively protected in a buffer area by using a system area information table and a mapping table, thereby remarkably reducing the size of the necessary buffer area.
1. An apparatus for protecting system data on a computer hard disk using a system area information table and a mapping table, the apparatus comprising:
an installation unit separately setting a system area and a buffer area on the computer hard disk and reserving areas for a meta information table, the system area information table, and the mapping table, respectively, and a data buffer area in the buffer area;
an initialization/recovery unit marking individual clusters in the system area with protection information in the system area information table based on one of a volume bitmap and a file allocation table (FAT) and initializing the mapping table and the data buffer area in the buffer area;
a write operation processing unit, with respect to a write operation on a cluster of the system area designated by a file system, performing the write operation on a cluster of the data buffer area designated by the mapping table when the cluster of the system area is marked as “protected” in the system area information table, and performing the write operation on the cluster of the system area designated by the file system when the cluster of the system area is marked as “non-protected”;
a read operation processing unit, with respect to a read operation on a cluster of the system area designated by the file system, performing the read operation on a cluster of the data buffer area designated by the mapping table, and performing the read operation on the cluster of the system area designated by the file system only when a value corresponding to the cluster of the system area indicates an initial state in the mapping table;
a current state backup unit sequentially reading all items of the mapping table one by one, reading data from a cluster of the data buffer area designated by a value of a read item of the mapping table and writing the data to a cluster of the system area corresponding to the cluster of the data buffer area when the value of the item does not indicate an initial state, and then calling the initialization/recovery unit to perform initialization; and
a removing unit removing the buffer area set by the installation unit to integrate the system area and the buffer area.
2. The apparatus of claim 1 , wherein when the cluster of the system area is marked as “protected” in the system area information table and has a value of the initial state in the mapping table, the write operation processing unit secures an empty space in the data buffer area, performs the write operation on a cluster allocated to the secured empty space, and records a position of the cluster, where new data is written, in a corresponding item block of the mapping table.
3. The apparatus of claim 1 , wherein when an original change mode has been set, the write operation processing unit performs the write operation on the cluster of the system area designated by the file system, and the read operation processing unit performs the read operation on the cluster of the system area designated by the file system.
4. A method of protecting system data on a computer hard disk using a system area information table and a mapping table, the method comprising the operations of:
(a) separately setting a system area and a buffer area on the computer hard disk and reserving areas for a meta information table, the system area information table, and the mapping table, respectively, and a data buffer area in the buffer area;
(b) marking individual clusters in the system area with protection information in the system area information table based on one of a volume bitmap and a file allocation table (FAT) and initializing the mapping table and the data buffer area in the buffer area;
(c) with respect to a write operation on a cluster of the system area designated by a file system, performing the write operation on a cluster of the data buffer area designated by the mapping table when the cluster of the system area is marked as “protected” in the system area information table, and performing the write operation on the cluster of the system area designated by the file system when the cluster of the system area is marked as “non-protected”;
(d) with respect to a read operation on a cluster of the system area designated by the file system, performing the read operation on a cluster of the data buffer area designated by the mapping table, and performing the read operation on the cluster of the system area designated by the file system only when a value corresponding to the cluster of the system area indicates an initial state in the mapping table;
(e) performing recovery by generating a new system area information table from one of the volume bitmap and the FAT and initializing the mapping table and the data buffer area in the buffer area; and
(f) removing the buffer area to integrate the system area and the buffer area.
5. The method of claim 4 , further comprising, before operation (e), (g) sequentially reading all items of the mapping table one by one, reading data from a cluster of the data buffer area designated by a value of a read item of the mapping table and writing the data to a cluster of the system area corresponding to the cluster of the data buffer area when the value of the item does not indicate the initial state, and then performing operation (b).
6. The method of claim 4 , wherein operation (c) comprises, when the cluster of the system area is marked as “protected” in the system area information table and has a value of the initial state in the mapping table, securing an empty space in the data buffer area, performing the write operation on a cluster allocated to the secured empty space, and recording a position of the cluster, where new data is written, in a corresponding item block of the mapping table.
7. The method of claim 4 , wherein when an original change mode has been set, operation (c) comprises performing the write operation on the cluster of the system area designated by the file system, and operation (d) comprise performing the read operation on the cluster of the system area designated by the file system.
8. The apparatus of claim 2 , wherein when an original change mode has been set, the write operation processing unit performs the write operation on the cluster of the system area designated by the file system, and the read operation processing unit performs the read operation on the cluster of the system area designated by the file system.