a non-malleable code is a variant of an encoding scheme which is resilient to tampering attacks. the main idea behind nonmalleable coding is that the adversary should not be able to obtain any valuable information about the message. non-malleablecodes are used in tamper-resilient cryptography and protecting memories against tampering attacks. many different types of nonmalleability have already...

A non-malleable code is a variant of an encoding scheme which is resilient to tampering attacks. The main idea behind non-malleable coding is that the adversary should not be able to obtain any valuable information about the message. Non-malleable codes are used in tamper-resilient cryptography and protecting memories against tampering attacks. Many different types of non-malleability have alre...

We construct non-malleable extractors with seed length d = O(log n+log(1/ε)) for n-bit sources with min-entropy k = Ω(d), where ε is the error guarantee. In particular, the seed length is logarithmic in n for ε > 2−(logn) 1/3 . This improves upon existing constructions that either require super-logarithmic seed length even for constant error guarantee, or otherwise only support min-entropy n/po...

The round complexity of non-malleable commitments and non-malleable zero knowledge arguments has been an open question for long time. Very recent results of Pass [TCC 2013] and of Goyal et al. [FOCS 2014, STOC 2016], gave almost definitive answers. In this work we show how to construct round-efficient non-malleable protocols via compilers. Starting from protocols enjoying limited non-malleabili...

We study ballot independence for election schemes. First, we formally define ballot independence as a cryptographic game and prove that ballot secrecy implies ballot independence. Secondly, we introduce a notion of controlled malleability and prove that it is sufficient for ballot independence. We also prove that non-malleable ballots are sufficient for ballot independence. Thirdly, we prove th...

We study ballot independence for election schemes: – We formally define ballot independence as a cryptographic game and prove that ballot secrecy implies ballot independence. – We introduce a notion of controlled malleability and show that it is sufficient for ballot independence. We also show that non-malleable ballots are sufficient, but not necessary, for ballot independence. – We prove that...