Designing Secret Embedding Scheme Based on Bitcoin Transactions Pattern Controlling

Blockchain with its decentralization, anti-tampering, traceability, anonymity and other technical characteristics, which provides mitigations to society issues such as data governance, information silo. However, the blockchain has inherent technical shortcomings such as its data openness and transparency and data permanent storage and other characteristics, which leads to security issues cannot be ignored, and may be subject to BGP hijacking attacks, distributed denial of service attacks, and node vulnerability attacks, which will bring greater risks to some private information, so an important alternative is to apply the covert channel. In this paper, we propose a secret embedding scheme based on Bitcoin transactions pattern controlling, where miner behaves secret embedding based on each single block transaction counts under block generating process. Our scheme adopts Gray code encoding to preprocess the covert information to be transmitted to improve the robustness of the scheme, uses transaction counts as a carrier and constructs a mapping table between transaction counts and secret information, which is embedded by intentionally modulating the transaction counts in the candidate blocks. Moreover, the distribution pattern of public traffics is simulated, so that the generated covert traffics are of undetectability. The implementation of our scheme is established under the real transaction scenarios, and our performance analysis shows that the proposed scheme is stealthy via KS test and KLD test, in addition, compared to the existing blockchain covert storage channel schemes based on transaction modification, our scheme’s overhead of transaction fee is zero.