We present a protocol enabling two legitimate partners sharing an initial
secret to mutually authenticate and to exchange an encryption session key. The
opponent is an active Man In The Middle (MITM) with unlimited computation and
storage capacities. The resistance to unlimited MITM is obtained through the
combined use of Deep Random secrecy, formerly introduced and proved as
unconditionally secure against passive opponent for key exchange, and universal
hashing techniques. We prove the resistance to MITM interception attacks, and
show that (i) upon successful completion, the protocol leaks no residual
information about the current value of the shared secret to the opponent, and
(ii) that any unsuccessful completion is detectable by the legitimate partners.
We also discuss implementation techniques.Comment: 14 pages. V2: Updated reminder in the formalism of Deep Random
assumption. arXiv admin note: text overlap with arXiv:1611.01683,
arXiv:1507.0825