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Non-malleable codes are kind of encoding schemes which are resilient to tampering attacks. The main idea behind the non-malleable coding is that the adversary can't be able to obtain any valuable information about the message. Non-malleable codes are used in tamper resilient cryptography and protecting memory against tampering attacks. Several kinds of definitions for the non-malleability exist in the literature. The Continuous non-malleability is aiming to protect messages against the adversary who issues polynomially many tampering queries. The first continuous non-malleable encoding scheme has been proposed by Faust et al. (FMNV) in 2014. In this paper, we propose a new method for proving... 

In this paper we try to unify the frameworks of definitions of semantic security, indistinguishability and non-malleability by defining semantic security in comparison based framework. This facilitates the study of relations among these goals against different attack models and makes the proof of the equivalence of semantic security and indistinguishability easier and more understandable. Besides, our proof of the equivalence of semantic security and indistinguishability does not need any intermediate goals such as non devidability to change the definition framework  

A non-malleable encoding scheme is a keyless encoding scheme which is resilient to tampering attacks. Such a scheme is said to be continuously secure if the scheme is resilient to attacks containing more than one tampering procedure. Moreover, such a scheme is said to have the T-tamper-detection property if any kind of tampering attack by an adversary chosen from a predetermined class of algorithms T is detected. Faust et al. have introduced a continuous non-malleable encoding scheme based on non-interactive zero-knowledge (NIZK) which is secure in a strong model for which the adversary receives the tampered codeword as a response to its tampering query if the tampered codeword is not...