Blockchain Driven Secure and Efficient Logging for Cloud Forensics

Abstract

Cloud computing is one of the most holistically used technology nowadays' due to its characteristics i.e. on-demand self-service, resource scalability, and measured service. However, public access to the data over the internet surges the risk of several malicious activities. It is essential to accumulate as well as safeguard justifiable facts of different events that happened in the cloud environment to find out the culprit through forensics. When a consumer performs any activity on the cloud, it gets caught in log files. Log files are very crucial to find out the offender as they keep track of consumers’ actions. However, logging the events that take place in the cloud and securing them while preserving the privacy of cloud consumers is a big challenge. Currently, cloud consumers are relying on cloud service providers to get the logs of events that take place on their personal data in spite of knowing the problem of multi-stakeholder collusion which may result in the fabrication of their logs. Thus, there is a strong requirement of publically verifiable secure logging which will play a vital role in doing criminal investigations without depending on third party. In this paper, we developed a BlockSLaaS, Blockchain-driven Secure Logging-as-a-Service scheme that supports, privacy-preserving (a) Secure Logging, (b) Eclectic Verification. Our scheme made a provision of securing the logs which guarantee the trustworthiness and reclamation of it in case of tampering to make a serene forensic investigation. As a substitute to blockchain storage; we proposed integrating the Interplanetary File System (IPFS), a decentralized off-chain data storage platform with blockchain for efficient logging and its visualization. This is bringing distributed processing along with efficient lookup strategy which makes data highly available for forensics. In existing work, the systems could offer the detection method for tampering of logs, but nobody delivered a reclamation mechanism. To comprehend the viability and deployment of the proposed scheme we used the ethereum blockchain and did experiments considering time and space requirements for different log file sizes and varying node count. Experimental results indicate that our proposed BlockSLaaS scheme is secure, efficient, and provable and gives better performance.