A provably secure oblivious transfer protocol
Proc. of the EUROCRYPT 84 workshop on Advances in cryptology: theory and application of cryptographic techniques
All-or-nothing disclosure of secrets
Proceedings on Advances in cryptology---CRYPTO '86
The notion of security for probabilistic cryptosystems
SIAM Journal on Computing - Special issue on cryptography
Founding crytpography on oblivious transfer
STOC '88 Proceedings of the twentieth annual ACM symposium on Theory of computing
Uses of randomness in algorithms and protocols
Uses of randomness in algorithms and protocols
CRYPTO '97 Proceedings of the 17th Annual International Cryptology Conference on Advances in Cryptology
A Practical Public Key Cryptosystem Provably Secure Against Adaptive Chosen Ciphertext Attack
CRYPTO '98 Proceedings of the 18th Annual International Cryptology Conference on Advances in Cryptology
On the Security of ElGamal Based Encryption
PKC '98 Proceedings of the First International Workshop on Practice and Theory in Public Key Cryptography: Public Key Cryptography
The Decision Diffie-Hellman Problem
ANTS-III Proceedings of the Third International Symposium on Algorithmic Number Theory
Deniable password snatching: on the possibility of evasive electronic espionage
SP '97 Proceedings of the 1997 IEEE Symposium on Security and Privacy
Malicious Cryptography: Exposing Cryptovirology
Malicious Cryptography: Exposing Cryptovirology
Information theoretic reductions among disclosure problems
SFCS '86 Proceedings of the 27th Annual Symposium on Foundations of Computer Science
Questionable encryption and its applications
Mycrypt'05 Proceedings of the 1st international conference on Progress in Cryptology in Malaysia
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In this paper we introduce a new tool that hides whether or not an "encryption" algorithm actually performs encryption or not. We call this a computational questionable encryption scheme and show how it can be used to devise mobile agents that conceal whether they encrypt or delete data prior to data transmission. Such agents may be useful in the honest-but-curious setting in which the author of the agent wishes to keep confidential whether or not the agent collects and transmits data while in transit. Informally, a questionable encryption scheme adds a "fake" key generation algorithm to a PKCS. The key generation algorithms of a computational questionable encryption scheme produce a "public key" y and a poly-sized witness x. Depending on which of the two key generation algorithms the user decides to use, y is real or fake. When the cipher is supplied with a real y then it produces decipherable ciphertexts and x proves this. When the cipher is supplied with a fake y then it produces computationally indecipherable ciphertexts (with respect to everyone) and x proves this. We call the former a witness of encryption and the latter a witness of non-encryption. We formally define the notion of a computational questionable encryption scheme and present a construction for it based on the ElGamal cryptosystem. We prove the security based on the Decision Diffie-Hellman problem and a reasonable new intractability assumption in the random oracle model. Finally, we show how a computational questionable encryption scheme is related yet different from all-or-nothing disclosure of secrets and related notions.