Trace and Confirm Your Ciphertext Unambiguously
Zhishuo Zhang, Yongjian Liao, Chunjiang Wu, Yating Huang, Huixi Yang, Shijie Zhou · 2025
To provide the encrypted data with public tamperproof and traceability, in this paper, we first explore and discuss that the alone signature attached to the encrypted data is in a low coupling state with the ciphertext which gives rise to signature substitution attack destructing assurance of the encrypted data. Then we propose a new cryptographic primitive called Secret-Embedded Ciphertext Signature of Knowledge (SECTSoK). And then give the general construction of SE-CTSoK in Schnorr identification scheme form over groups. The proposed SE-CTSoK is not only a signature for the ciphertext to make the ciphertext tamper-proof, but also a zero-knowledge argument of the ciphertext random secret to give the proof that the ciphertext secret is embedded in SE-CTSoK for sure without revealing it. Furthermore, we introduce the standardized definition of the Irreconfigurability model for the ciphertext signature to cover any type of the signature substitution attack, and then we give the formalized proof to our proposed SE-CTSoK in Irreconfigurability model which demonstrates that the ciphertext with the corresponding SE-CTSoK can only be correctly traced and confirmed to the ciphertext generator.