Another look at HMAC
| Autor: | Neal Koblitz, Alfred Menezes |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2013 |
| Předmět: |
Provable security
Computer science Applied Mathematics Proof of security Hash-based message authentication code Computer security computer.software_genre Computer Science Applications nmac Computational Mathematics message authentication code hmac QA1-939 NIST Message authentication code provable security Separation result Value (mathematics) computer Mathematics Security guarantee |
| Zdroj: | Journal of Mathematical Cryptology, Vol 7, Iss 3, Pp 225-251 (2013) |
| ISSN: | 1862-2984 1862-2976 |
| Popis: | HMAC is the most widely-deployed cryptographic-hash-function-based message authentication code. First, we describe a security issue that arises because of inconsistencies in the standards and the published literature regarding keylength. We prove a separation result between two versions of HMAC, which we denote HMAC and HMAC, the former being the real-world version standardized by Bellare et al. in 1997 and the latter being the version described in Bellare’s proof of security in his Crypto 2006 paper. Second, we describe how HMAC (the FIPS version standardized by NIST), while provably secure (in the single-user setting), succumbs to a practical attack in the multi-user setting. Third, we describe a fundamental defect from a practice-oriented standpoint in Bellare’s 2006 security result for HMAC, and show that because of this defect his proof gives a security guarantee that is of little value in practice. We give a new proof of NMAC security that gives a stronger result for NMAC and HMAC and we discuss why even this stronger result by itself fails to give convincing assurance of HMAC security. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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