/*
 * Modeled from ISO/IEC 9798
 * Modeler: Cas Cremers, Dec. 2010, Feb. 2011.
 *
 * History:
 * 
 * - v2.0, Feb. 2011:
 *   Added key symmetry emulation protocol.
 *
 * ccf
 * unilateral
 * two-pass
 * 
 * The identifier B is optional and may be omitted if the key is unidirectional.
 * 
 * Modeling notes:
 *
 * - The keyed CCF (f_kab(x)) is modeled as f(x,kab)
 */
hashfunction f;

protocol @keysymm-42(A,B)
{
	role A
	{
		var X,Y,Z: Ticket;

		recv_!1(B,A, f(X,Y,Z, k(A,B) ) );
		send_!2(A,B, f(X,Y,Z, k(B,A) ) );
	}
	role B
	{
	}
}

protocol isoiec-9798-4-2(A,B)
{
	role A
	{
		var Rb: Nonce;
		var Text1: Ticket;
		fresh Text2,Text3: Ticket;

		recv_1(B,A, Rb,Text1 );
		claim(A,Running,B,Rb,Text2);
		send_2(A,B, Text3, f( Rb, B, Text2, k(A,B)) );
	}
	role B
	{
		fresh Rb: Nonce;
		fresh Text1: Ticket;
		var Text2,Text3: Ticket;

		send_1(B,A, Rb,Text1 );
		recv_2(A,B, Text3, f( Rb, B, Text2, k(A,B)) );

		claim(B,Commit,A,Rb,Text2);
		claim(B,Alive);
		claim(B,Weakagree);
	}
}