We propose a new message authentication code MAC based on a tweakable block cipher TBC. We prove that the new MAC is a pseudo-random function PRF upi¾?to $$O2^n$$ queries, that is, full PRF-security, where the output length of the TBC is n bits. We note that although Yasuda proposed a full PRF-secure MAC based on a compression function CF, that does not offer a full PRF-secure TBC-based MAC due to the PRF/PRF switch. Hence our MAC is the first full PRF-secure one based on a TBC.
['Yusuke Naito']
Full PRF-Secure Message Authentication Code Based on Tweakable Block Cipher