80 lines
1.7 KiB
C++
80 lines
1.7 KiB
C++
|
/** HEADDOC
|
||
|
* @protocol SKEME
|
||
|
* @reference Krawczyk, H., SKEME: A Versatile Secure Key Exchange Mechanism
|
||
|
* for Internet,
|
||
|
* Boyd C. and Mathuria A., Protocols for Authentication and
|
||
|
* Key Agreement
|
||
|
* @description SKEME is a set of protocols suitable for negotiation of
|
||
|
* services in a general networked environment. The main
|
||
|
* characteristics are forward secrecy, privacy and anonymity,
|
||
|
* and DoS protection.
|
||
|
* @variant Fast rekeying protocol
|
||
|
**/
|
||
|
|
||
|
/** MACRO DEFINITIONS
|
||
|
* Needs preprocessing by cpp before fed to scyther
|
||
|
**/
|
||
|
#define __SKEME_REKEY__
|
||
|
#ifndef __ORACLE__
|
||
|
#include "common.h"
|
||
|
#endif
|
||
|
|
||
|
/**
|
||
|
* This role serves as an "oracle" to ensure the executability of the
|
||
|
* protocol by taking care of the problems that arise from our way of
|
||
|
* modelling k(I,R) = k(R,I).
|
||
|
*/
|
||
|
protocol @executability(O) {
|
||
|
#define Gi g(i)
|
||
|
#define Gr g(r)
|
||
|
role O {
|
||
|
var Ni, Nr: Nonce;
|
||
|
var I, R: Agent;
|
||
|
|
||
|
// msg 2
|
||
|
recv_!O1( O, O, prf(k(R,I), Ni, Nr, R, I) );
|
||
|
send_!O2( O, O, prf(k(I,R), Ni, Nr, R, I) );
|
||
|
|
||
|
// msg 3
|
||
|
recv_!O3( O, O, prf(k(I,R), Nr, Ni, I, R) );
|
||
|
send_!O4( O, O, prf(k(R,I), Nr, Ni, I, R) );
|
||
|
|
||
|
}
|
||
|
#undef Gi
|
||
|
#undef Gr
|
||
|
}
|
||
|
|
||
|
protocol skeme-rekey(I, R)
|
||
|
{
|
||
|
role I {
|
||
|
fresh Ni: Nonce;
|
||
|
var Nr: Nonce;
|
||
|
|
||
|
send_1( I, R, Ni );
|
||
|
recv_!2( R, I, Nr, prf(k(I,R), Ni, Nr, R, I) );
|
||
|
send_!3( I, R, prf(k(I,R), Nr, Ni, I, R) );
|
||
|
|
||
|
/* SECURITY CLAIMS */
|
||
|
claim( I, SKR, SKi );
|
||
|
|
||
|
claim( I, Alive );
|
||
|
claim( I, Weakagree );
|
||
|
|
||
|
}
|
||
|
|
||
|
role R {
|
||
|
fresh Nr: Nonce;
|
||
|
var Ni: Nonce;
|
||
|
|
||
|
recv_1( I, R, Ni );
|
||
|
send_!2( R, I, Nr, prf(k(I,R), Ni, Nr, R, I) );
|
||
|
recv_!3( I, R, prf(k(I,R), Nr, Ni, I, R) );
|
||
|
|
||
|
/* SECURITY CLAIMS */
|
||
|
claim( R, SKR, SKr );
|
||
|
|
||
|
claim( R, Alive );
|
||
|
claim( R, Weakagree );
|
||
|
|
||
|
}
|
||
|
}
|