Security of NMACand HMACBased on Non-malleability
نویسنده
چکیده
We give an alternative security proof for NMAC and HMAC when deployed as a message authentication code, supplementing the previous result by Bellare (Crypto 2006). We show that (black-box) non-malleability and unpredictability of the compression function suffice in this case, yielding security under different assumptions. This also suggests that some sort of non-malleability is a desirable design goal for hash functions.
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