scyther/protocols/misc/bkepk-ce.spdl

/* 
	Bilateral Key Exchange with Public Key protocol (bkeCE)

	Version from Corin/Etalle: An Improved Constraint-Based System for the Verification of Security Protocols.
	Tried to stay as close as possible to compare timing results.
*/

usertype Key;

const pk,hash: Function;
secret sk,unhash: Function;

inversekeys (pk,sk);
inversekeys (hash,unhash);

protocol bkeCE(A,B)
{
	role A
	{
		var nb: Nonce;
		const na: Nonce;
		const kab: Key;

		read_1 (B,A, B,{ nb,B }pk(A) );
		send_2 (A,B, { hash(nb),na,A,kab }pk(B) );
		read_3 (B,A, { hash(na) }kab );

		claim_A1 (A, Secret, na);
		claim_A2 (A, Secret, nb);
	}

	role B
	{
		const nb: Nonce;
		var na: Nonce;
		var kab: Key;

		send_1 (B,A, B,{ nb,B }pk(A) );
		read_2 (A,B, { hash(nb),na,A,kab }pk(B) );
		send_3 (B,A, { hash(na) }kab );

		claim_B1 (B, Secret, na);
		claim_B2 (B, Secret, nb);
	}

}

const Alice,Bob,Eve;

compromised sk(Eve);
untrusted Eve;