Cryptanalysis of Tav-128 hash function
Many RFID protocols use cryptographic hash functions for their security. The resource constrained nature of RFID systems forces the use of light weight cryptographic algorithms. Tav-128 is one such 128-bit light weight hash function proposed by Peris-Lopez et al. for a low-cost RFID tag authentication protocol. Apart from some statistical tests for randomness by the designers themselves, Tav-128 has not undergone any other thorough security analysis. Based on these tests, the designers claimed that Tav-128 does not posses any trivial weaknesses. In this article, we carry out the first third party security analysis of Tav-128 and show that this hash function is neither collision resistant nor second preimage resistant. Firstly, we show a practical collision attack on Tav-128 having a complexity of 237 calls to the compression function and produce message pairs of arbitrary length which produce the same hash value under this hash function. We then show a second preimage attack on Tav-128 which succeeds with a complexity of 262 calls to the compression function. Finally, we study the constituent functions of Tav-128 and show that the concatenation of nonlinear functions A and B produces a 64-bit permutation from 32-bit messages. This could be a useful light weight primitive for future RFID protocols.
Date of Appearance
Kumar , A , Sanadhya , S K , Gauravaram , P , Safkhani , M & Naderi , M 2010 , Cryptanalysis of Tav-128 hash function . in G Gong & K C Gupta (eds) , Proceedings of Indocrypt 2010 : 11th International Conference on Cryptology in India . Springer , Lecture Notes in Computer Science , vol. 6498 , pp. 118-130 , 11th International Conference on Cryptology in India , Hyderabad , India , 12/12/2010 . https://doi.org/10.1007/978-3-642-17401-8_10