细粒度的数据完整性检验可以减小因偶然的错误或个别的篡改而造成的数据失效的灾难性影响,成为计算机取证的重要需求.每份数据各自生成Hash值的方法会产生大量的Hash数据.因Hash数据属于随机性数据而无法压缩,给Hash数据存储及网络传输带来不利影响.针对细粒度数据的完整性检验问题,提出了基于纠错编码思想的细粒度数据完整性检验方法——完整性指示码,给出了完整性指示码的若干性质.设计了指示单个错误的组合单错码,分析了该码的基本性能.结果表明,该码可以轻易地达到几百倍的压缩率.得出的结论为细粒度数据完整性检验的进一步研究及相关的应用提供了理论支持.
Fine-Grained integrity check for forensic data becomes an important demand of computer forensics. It will mitigate the disasterous effect on the data by some random errors or the intentional forging modification.Unfortunately, the traditional method generates a hash for every piece of small data and produces a large amount of hash data. These hash data are random data and can not be compressed in a normal way. It has a great negative impact on storing hash data and transmitting them over network. Based on the error correction coding theory, a fine-grained integrity check method, an integrity indication code, is proposed. The properties of the integrity indication code are analyzed. Combinatorial codes for one error in a group of data objects are also proposed. Hash data can be compressed hundredfold using combinatorial codes. This paper provides a fundamental support for further research on fine-grain data integrity check method and related applications.