Moved Amended-Needham Schroeder into done_examples (temporary measure until...

Moved Amended-Needham Schroeder into done_examples (temporary measure until all of the example theories have been properly converted into the latest Maude-PSL version). Also removed Amended-NS which was just a differently named file of the same protocol as Amended-Needham-Schroeder, and therefore not necessary.

examples/Amended-NS.psl

-spec Amended-NS is
-
-Theory
-  types SName Name Key Nonce Masterkey Sessionkey .
-  subtype Masterkey Sessionkey < Key .
-  subtype SName < Name .
-  subtype Name < Public . 
-  op n : Name Fresh -> Nonce .
-  ops a b i : -> Name [ctor] .
-  op s : ->  SName [ctor] . 
-  op mkey : Name Name -> Masterkey .
-  op seskey : Name Name Nonce -> Sessionkey .
-  op e : Key Msg -> Msg .
-  op d : Key Msg -> Msg .
-  op dec : Nonce -> Msg .
-  op _;_ : Msg Msg -> Msg [gather (e E)] .
-  
-  eq d(K:Key, e (K:Key, Z:Msg )) = Z:Msg  . 
-  eq e(K:Key, d (K:Key, Z:Msg )) = Z:Msg  .
-
-  
-/*
- A -> B : A
- B -> A : E(Kbs:A,Nb0)
- A -> S : A,B,Na,E(Kbs:A,Nb0)
- S -> A : E(Kas:Na,B,Kab,E(Kbs:Kab,Nb0,A))
- A -> B : E(Kbs:Kab,Nb0,A)
- B -> A : E(Kab:Nb)
- A -> B : E(Kab:Nb-1)
-*/
-
-Protocol
-  vars A B : Name .
-  var S : SName .  
-  vars r r0 r1 : Fresh .
-  vars NA NB NB0 : Nonce .
-  var K : Key .
-  var X Y Z MB MB' : Msg .
-  var SK : Sessionkey .
-
-  Def(A) = na := n(A, r) , kas := mkey(A,s) .
-  In(A) = A, B, S  .
-
-  Def(B) = nb0 := n(B, r0), nb := n(B, r1) , kbs := mkey(B,s) .
-  In(B) = A, B, S .
-
-  Def(S) = kas := mkey(A,S), kbs := mkey(B,S), kab := seskey(A,B,n(S,r)) .
-  In(S) = A, B, S . 
-
-  1 . A -> B :  A |- A .
-
-  2 . B -> A :  e(kbs, A ; nb0 ) |- MB .
-
-  3 . A -> S :  A ; B ; na ; MB 
-             |- A ; B ; NA ; e(kbs, A ; NB0) .
-
-  4 . S -> A : e(kas , NA ; B ; kab ; e(kbs, kab ; NB0 ; A))
-            |- e(kas , na ; B ; SK  ; MB') .
-   
-  5 . A -> B : MB' |- e(kbs, SK ; nb0 ; A) .
-
-  6 . B -> A : e(SK, nb) 
-            |- e(SK, NB) .
-
-  7 . A -> B : e(SK, dec(NB))
-            |- e(SK, dec(nb)) .
-
-  Out(A) = na, NB0 , NB, SK .
-  Out(B) = NA, nb0, nb, SK .
-  Out(S) = NA, NB0, kab .
-
-Intruder
-  vars A B : Name .
-  var K : Key .
-  vars X Y : Msg .
-  var NA : Nonce .
-  var r : Fresh .
-
-  => A, mkey(i, A), mkey(A, i), n(i, r) .
-  X ; Y <=> X , Y .
-  X, K => d(K, X), e(K, X) .
-  NA => dec(NA) .
-
-Attacks
-  vars A B : Name .
-  var S : SName .
-  0 . 
-       In(B) = A |-> a , B |-> b , S |-> s . 
-       B executes protocol .
-       Out(B) = ditto .
-
-ends