scyther/gui/Protocols/IKE/sts-main.cpp
Cas Cremers 34d7cba293 Added IKE base models.
Modelers: Adrian Kyburz and Cas Cremers
2012-11-15 11:48:14 +01:00

79 lines
1.7 KiB
C++

/** HEADDOC
* @protocol Station-to-Station Protocol (STS)
* @reference Diffie W., van Oorschot P. C., and Wiener M. J.,
* Authentication and authenticated key exchange,
* Boyd C. and Mathuria A., Protocols for Authentication and
* Key Agreement
* @description STS adds a digital signaure to the exchanged messages to
* provide authentication for the Diffie-Hellman protocol. In
* addition, the shared secret is used to provide further
* assurances.
**/
#define __STS__
#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 Diffie-Hellman keys.
*/
protocol @executability(O) {
#define Gi g(i)
#define Gr g(r)
role O {
var i, r: Nonce;
var I, R: Agent;
// msg 2
recv_!O1( O, O, {{g(r), Gi}sk(R)}SKr );
send_!O2( O, O, {{g(r), Gi}sk(R)}SKi );
// msg 3
recv_!O3( O, O, {{g(i), Gr}sk(I)}SKi );
send_!O4( O, O, {{g(i), Gr}sk(I)}SKr );
}
#undef Gi
#undef Gr
}
// It is not specified how the session key is derived from the ephemeral DH
// secret Z; we use KDF(Z).
protocol sts-main(I, R)
{
role I {
fresh i: Nonce;
var Gr: Ticket;
send_1( I, R, g(i) );
recv_!2( R, I, Gr, {{Gr, g(i)}sk(R)}SKi );
send_!3( I, R, {{g(i), Gr}sk(I)}SKi );
/* SECURITY CLAIMS */
claim( I, SKR, SKi );
claim( I, Alive );
claim( I, Weakagree );
}
role R {
fresh r: Nonce;
var Gi: Ticket;
recv_1( I, R, Gi );
send_!2( R, I, g(r), {{g(r), Gi}sk(R)}SKr );
recv_!3( I, R, {{Gi, g(r)}sk(I)}SKr );
/* SECURITY CLAIMS */
claim( R, SKR, SKr );
claim( R, Alive );
claim( R, Weakagree );
}
}