cpsa-4.4.1: coq/Examples/privk2.scm
(herald privk2)
(defprotocol privk2 basic
(defrole rho
(vars (ch chan) (a name) (k akey))
(trace
(recv ch (enc a (privk "enc" a) k))
(send ch (enc a (privk "enc" a))))
(inputs ch (invk k))))