LiTIV: A Lightweight Traceable Data Integrity Verification Scheme for Version Control Systems

Conventional data integrity solutions for Version Control Systems (VCSs) include hash verification, commit signature and log-based schemes. However, existing schemes either bring heavy burden to the VCS client, or place high requirements on the VCS server. These schemes are incapable of offering a lightweight service. Moreover, existing schemes cannot offer corruption provenance that facilitates corruption location and version recovery. To address these challenges, we present LiTIV, a lightweight traceable data integrity verification scheme for VCS. LiTIV introduces a third-party verification server, namely Data Verifier (DV), which effectively reduces impacts on the VCS client and server. LiTIV exploits index history table (IHT) along with signed commit information to achieve both integrity and traceability. Besides, a balanced Merkle hash tree (BMT) is designed and adopted to achieve fast data updating and efficient integrity verification. In case of malicious tampering of V CS file system disks, LiTIV can rely on the BMT structure to effectively detect implicit inconsistency, and achieve backtracking for tam-pering provenance with IHT query. We also design a probabilistic sampling verification mechanism on historical commits to achieve high performance under security premise. Extensive evaluations show that LiTIV achieves traceable integrity security against various attacks and is highly efficient.