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Diffstat (limited to 'security/p5-Digest-EMAC/pkg-descr')
| -rw-r--r-- | security/p5-Digest-EMAC/pkg-descr | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/security/p5-Digest-EMAC/pkg-descr b/security/p5-Digest-EMAC/pkg-descr new file mode 100644 index 000000000000..b968c595188c --- /dev/null +++ b/security/p5-Digest-EMAC/pkg-descr @@ -0,0 +1,23 @@ +This is Encrypted MAC (EMAC), formerly known as Double MAC (DMAC). +Unlike HMAC, which reuses an existing one-way hash function, such as +MD5, SHA-1 or RIPEMD-160, EMAC reuses an existing block cipher to +produce a secure message authentication code (MAC). + +Using the block cipher, a message is encrypted in CBC mode. The last +block is taken as the MAC of the message. For fixed-length messages, +this method is provably secure. In reality, however, messages have +arbitrary lengths, and this method is not secure. To make secure MACs +for variable length messages, the last block is encrypted once again +with a different key. The security of this construction has been proved +in the paper, ``CBC MAC for Real-Time Data Sources'' by Erez Petrank +and Charles Rackoff. The security can be proved on the assumption that +the underlying block cipher is pseudo-random. + +The performance and key-agility of EMAC are reasonable. EMAC is +preferable for short messages because the block length is smaller +compared to the schemes based on a hash function. EMAC is also chosen +as one of the NESSIE winners for Message Authentication Codes, along +with UMAC, TTMAC and HMAC. The current NESSIE specification chooses the +AES as block cipher. + +WWW: http://search.cpan.org/dist/Digest-EMAC |