PinTar: message authentication code based on quasigroup and permutation compression function

In the era of Information Security, Message Authentication Codes (MACs) are used to verify the integrity of messages that are sent or received over an insecure channel. Traditionally, MAC algorithms are constructed by using existing block ciphers as underlying compression function due to the challenges and difficulties faced in constructing new MACs from the scratch. However, block ciphers requires key scheduling for encryption and this process impacts the performance of the MAC. As a result, permutation compression functions based on permutations and XOR were proposed as alternatives to block ciphers. Consequently, these constructions of have been shown certain limitations. This research proposes an efficient and secure compression function based on the theory of quasigroup and permutation, as a remedy for the draw backs of permutation based compression functions. In addition, a new variable length MAC (128 bits, 256 bits and 512 bits) has been proposed based on the proposed compression function. The security of the proposed compression function and MAC algorithm was analyzed based on statistical analysis. Average correlation assessment of 0.094 was obtained for the proposed compression function. Randomness of compression function was analyzed and average P - value of 0.4354 was obtained for randomness test using NIST statistical test tool. Furthermore, PinTar MAC algorithm is shown to have a key space of 2^19 factorial (2^19!), which makes the MAC highly resistant against key exhaustive search attack, compared to DES and AES block ciphers which have key space of 2^56 and 2^128 respectively. Avalanche result of 97%, 94%, 94% and 88% was obtained for 128 bits of PinTar MAC, MD5, MD4 and MD2 respectively. PinTar MAC has also been shown to be resistant against adaptive chosen text attack due to the very large key space. Finally, it can be concluded that PinTar MAC and its compression function are efficient, and can serve as alternative algorithms in designing security systems.