How to construct pseudo-random permutations from pseudo-random functions
Lecture notes in computer sciences; 218 on Advances in cryptology---CRYPTO 85
CBC MACs for Arbitrary-Length Messages: The Three-Key Constructions
CRYPTO '00 Proceedings of the 20th Annual International Cryptology Conference on Advances in Cryptology
Online Ciphers and the Hash-CBC Construction
CRYPTO '01 Proceedings of the 21st Annual International Cryptology Conference on Advances in Cryptology
The Security of Cipher Block Chaining
CRYPTO '94 Proceedings of the 14th Annual International Cryptology Conference on Advances in Cryptology
LFSR-based Hashing and Authentication
CRYPTO '94 Proceedings of the 14th Annual International Cryptology Conference on Advances in Cryptology
Two New Efficient CCA-Secure Online Ciphers: MHCBC and MCBC
INDOCRYPT '08 Proceedings of the 9th International Conference on Cryptology in India: Progress in Cryptology
Software performance of universal hash functions
EUROCRYPT'99 Proceedings of the 17th international conference on Theory and application of cryptographic techniques
Two New Efficient CCA-Secure Online Ciphers: MHCBC and MCBC
INDOCRYPT '08 Proceedings of the 9th International Conference on Cryptology in India: Progress in Cryptology
Online ciphers from tweakable blockciphers
CT-RSA'11 Proceedings of the 11th international conference on Topics in cryptology: CT-RSA 2011
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Online ciphers are those ciphers whose ciphertexts can be computed in real time by using a length-preserving encryption algorithm. HCBC1 and HCBC2 are two known examples of Hash Cipher Block Chaining online ciphers. The first construction is secure against chosen plaintext adversary (or called CPA-secure) whereas the latter is secure against chosen ciphertext adversary (or called CCA-secure). In this paper, we have provided simple security analysis of these online ciphers. We have also proposed two new more efficient chosen ciphertext secure online ciphers modified-HCBC (MHCBC) and modified-CBC (MCBC). If one uses a finite field multiplication based universal hash function, the former needs one less key and one less field multiplication compared to HCBC2. The MCBC does not need any universal hash function and it needs only one blockcipher key unlike the other three online ciphers where two independent keys (hash function and blockcipher) are required.