| It has been talking frequently about the security of computer system and data. However, that does not mean the problem has been resolved well. On the contrary, people are still unsatisfied with it. In recent years some disk tools which make Master Boot Sector visible to users, such as KV3000, DISKEDIT and PCTOOLS bring not only convenience but also insecurity even danger. Attack of virus, modification of hackers and accidental operation may cause system crash and data loss. Master Boot Sector more and more becomes the target of virus. So how to ensure the data security in Master Boot Sector has been very important in the research of the information technology security field.According to the significance and the particularity of Master Boot Sector, people present several methods to protect the data in it: (1) saving the data into chips, (2) using hard disk protecting card, (3) Advanced Sector Protection technology, (4) RAID. The industry applicationindicates that these technologies work well in validity, but there are many problems in facility, maintainability and thoroughness. Meanwhile, it is unable to resist the threat, coming from thousands of different networks and non-networks, to protect the data in Master Boot Sector with its invisibility. Thereby a comprehensive data saving and restoring strategy which is executed easily should been given to protect the data in Master Boot Sector.When the above requirements are considered, this research is about to find solutions to the problems mentioned above from the outer and inner sides. Here the OUTER side can be understood as the outside causes which lead to damage to the data in Master Boot Sector or booting computer system from any medium except hard disk. In the second case a functional module using the XOR coding embeds in Master Boot Record (MBR), which makes booting from hard disk only in order to stop the data in Master Boot Sector from damage. Here the INNER side, which is opposite to the OUTER side, can be understood as the inside causes which lead to damage to the data in Master Boot Sector or booting computer system only from hard disk. In this case the data is saved to a file and can be restored from it.As a very special example of restoring the data into Master Boot Sector and considering about the fundamentality of Disk Partition Table (DPT), a new DPT restoration algorithm is put forward which based onthe data structure of each node in the Partition Table Link and the effectiveness of Extended INT 13H in accessing the data on disks. In theory all the partition tables can be restored by using this algorithm after they have been partially or totally damaged.This research has some characteristics and innovations as follows:1. It is a comprehensive data protecting system in Master Boot Sector. The integrality and the security are enhanced by bringing the outer side and the inner side together.2. By taking the advantage of linear addressing and Extend INT 13H, the protecting methods put forward in this research can be applied to hard disks that capacity is larger than 8.4 gigabytes as well as old types.3. The restoration of DPT is based on the Partition Table Link. That means all the partition tables can be restored after they have been partially or totally damaged by using new DPT restoration algorithm. Therefore the situation that the extended partition is missing though the primary partition still exists will not happen.This thesis begins with the demand and background of the data security in Master Boot Sector. Then it analyzes the supporting technologies for the protection of the data. After putting forward some outer and inner protecting methods, it analyzes and expounds a new DPT restoration algorithm. As a simulation of the inner protecting method, the code is written which implemented in C language. |
PDF Full Text Request