Class Cryptokit.Block.mac_final_triple

class mac_final_triple : ?iv:string ->
       ?pad:Cryptokit.Padding.scheme ->
       block_cipher ->
       block_cipher ->
       block_cipher -> Cryptokit.hash

Build a MAC (keyed hash function) from the given block ciphers c1, c2 and c3. The input is run through c1 in CBC mode, as described for Cryptokit.Block.mac. The final initialization vector is then super-enciphered by c2, then by c3, to provide the final MAC. This construction results in a MAC that is as nearly as fast as Cryptokit.Block.mac c1, but more resistant against brute-force key search because of the additional final encryption through c2 and c3.