def cmac

bend-osdev-crypto@0.1.0.0 · check.bend:229

import Base
import bend-osdev-bytes@0.1.0.0/bytes.bend as B
import bend-osdev-cipher-modes@0.1.0.0/aes.bend as X
import bend-osdev-crypto@0.1.0.0/crypto.bend as Cr
import bend-osdev-crypto@0.1.0.0/mac.bend as Mc
import bend-osdev-crypto@0.1.0.0/inst_aes.bend as A
import bend-osdev-crypto@0.1.0.0/inst_cmac.bend as CMI

229def cmac(+k: B.Octets, +m: B.Octets) -> String:
230  +t = Mc.CrMac.compute_with(~X.CmAesKey, ~A.CrAes.key_enc, ~CMI.CrCmac.mac(~X.CmAesKey, ~X.CmAes.encrypt), k, m)
231  cat(show(t), cr.check.verify(Result.map(&2, &2, Cr.CrError, B.Octets, Bool, +tag => Result.default(&2, &2, Cr.CrError, Bool, Result.map(&2, &2, Cr.CrError, X.CmAesKey, Bool, +kk => Bool.and(CMI.CrCmac.verify(~X.CmAesKey, ~X.CmAes.encrypt, kk, m, tag), Bool.not(CMI.CrCmac.verify(~X.CmAesKey, ~X.CmAes.encrypt, kk, m, flip_last(tag)))), A.CrAes.key_enc(k)), False{}), t)))