Chameleon All-But-One TDFs And Their Applications

Lossytrapdoorfunctions(LTDFs)andall-but-onetrapdoorfunctions(ABO-TDFs)wereintroducedbyPeikertandWaters[1]. Thesetwoprimitiveswereusedtoconstruc-t several important cryptographic tools including CCA-secure public key encryption(PKE). Later, Lai et al.[2] introduced the concept of chameleon ABO-TDFs, and pro-posed a more efcient black-box construction of PKE with the help of it.Inthispaper, wefrstreviewthedefnitionsofinjectivetrapdoorfunctions, LTDF-s, ABO-TDFs, and chameleon ABO-TDFs. We also instantiate the frst chameleonABO-TDFsbasedonDDHassumptionandfreeofchameleonhashfunctions. Thenwewill emphasize on various applications of chameleon ABO-TDFs, including collision-resistant hash functions, universal one-way hash functions, pseudoentropy generators,pseudorandom generators, strongly unforgeable signatures, and deterministic encryp-tion schemes.