public void TestIEWithSerialized()
{
// Does a complete encrypt/decrypt sequence from serialized values.
// Kind of redundant because each of the testmethods above test serialization
// of individual data types
//Serialize and deserialize all objects
IDEscrowParams ieParam2 = ip.Deserialize <IDEscrowParams>(ip.Serialize(ieParam));
IDEscrowPublicKey pk2 = ip.Deserialize <IDEscrowPublicKey>(ip.Serialize(pk));
IDEscrowPrivateKey sk2 = ip.Deserialize <IDEscrowPrivateKey>(ip.Serialize(sk));
// Encrypt
FieldZq F = ip.Zq;
FieldZqElement xb2 = F.GetRandomElement(true);
FieldZqElement ob2 = F.GetRandomElement(true);
GroupElement Cxb2 = ip.Gq.G.Exponentiate(xb2); // Cxb = g^xb
Cxb2 = Cxb2.Multiply(ip.G[1].Exponentiate(ob2)); // Cxb = (g^xb)*(g1^ob)
GroupElement PE2 = ieParam2.Ge.Exponentiate(xb2);
IDEscrowCiphertext ctext2 = IDEscrowFunctions.VerifiableEncrypt(ieParam2, pk2, tokenID, Cxb2, xb2, ob2, additionalInfo);
ctext2 = ip.Deserialize <IDEscrowCiphertext>(ip.Serialize(ctext2));
// Verify
bool isValid = IDEscrowFunctions.Verify(ieParam2, ctext2, tokenID, pk2, Cxb2);
Assert.IsTrue(isValid);
// Decrypt
GroupElement PEPrime = IDEscrowFunctions.Decrypt(ieParam2, ctext2, sk2);
Assert.IsTrue(PE2.Equals(PEPrime));
}
public void TestIEVerify()
{
// Verify
bool isValid = IDEscrowFunctions.Verify(ieParam, ctext, tokenID, pk, Cxb);
Assert.IsTrue(isValid);
}
public void TestIEWithRealToken()
{
/********** begin: this section of code taken from EndToEndTest.cs, TestMethod PseudonymAndCommitmentsTest *****/
System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
// Issuer setup
IssuerSetupParameters isp = new IssuerSetupParameters(maxNumberOfAttributes);
isp.UidP = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
isp.E = new byte[] { (byte)1, (byte)1, (byte)1, (byte)1 };
isp.UseRecommendedParameterSet = true;
isp.S = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
IssuerKeyAndParameters ikap = isp.Generate();
IssuerParameters ip2 = ikap.IssuerParameters;
// Issuance
byte[][] attributes = new byte[][] { encoding.GetBytes("Attribute 1"), encoding.GetBytes("Attribute 2"), encoding.GetBytes("Attribute 3"), encoding.GetBytes("Attribute 4") };
byte[] tokenInformation = new byte[] { };
byte[] proverInformation = new byte[] { };
int numberOfTokens = 1;
IssuerProtocolParameters ipp = new IssuerProtocolParameters(ikap);
ipp.Attributes = attributes;
ipp.NumberOfTokens = numberOfTokens;
ipp.TokenInformation = tokenInformation;
Issuer issuer = ipp.CreateIssuer();
FirstIssuanceMessage msg1 = issuer.GenerateFirstMessage();
ProverProtocolParameters ppp = new ProverProtocolParameters(ip2);
ppp.Attributes = attributes;
ppp.NumberOfTokens = numberOfTokens;
ppp.TokenInformation = tokenInformation;
ppp.ProverInformation = proverInformation;
Prover prover = ppp.CreateProver();
SecondIssuanceMessage msg2 = prover.GenerateSecondMessage(msg1);
ThirdIssuanceMessage msg3 = issuer.GenerateThirdMessage(msg2);
UProveKeyAndToken[] upkt = prover.GenerateTokens(msg3);
// Pseudonym
int[] disclosed = new int[0];
int[] committed = new int[] { 2, 4 };
byte[] message = encoding.GetBytes("this is the presentation message, this can be a very long message");
byte[] scope = encoding.GetBytes("scope");
PresentationProof proof;
FieldZqElement[] tildeO;
// Valid presentation
proof = PresentationProof.Generate(ip2, disclosed, committed, 1, scope, message, null, null, upkt[0], attributes, out tildeO);
try { proof.Verify(ip2, disclosed, committed, 1, scope, message, null, upkt[0].Token); }
catch { Assert.Fail("Proof failed to verify"); }
/******** end code from EndToEndTest.cs ***********/
// Use the commitment to attribute x_2 for ID escrow
GroupElement Cx2 = proof.Commitments[0].TildeC; // x2 is the first committed attribute
FieldZqElement x2 = ProtocolHelper.ComputeXi(ip2, 1, attributes[1]); // attributes[] is zero indexed.
FieldZqElement tildeO2 = tildeO[0];
// double check that Cx2 is computed as we expect.
GroupElement Cx2Prime = ip2.Gq.G.Exponentiate(x2);
Cx2Prime = Cx2Prime.Multiply(ip2.G[1].Exponentiate(tildeO2));
Assert.IsTrue(Cx2Prime.Equals(Cx2));
// Setup
IDEscrowParams ieParam3 = new IDEscrowParams(ip2);
IDEscrowPrivateKey priv = new IDEscrowPrivateKey(ieParam3); // we can't re-use the keypair above, it was created with different issuer params
IDEscrowPublicKey pub = new IDEscrowPublicKey(ieParam3, priv);
byte[] tokenID = ProtocolHelper.ComputeTokenID(ip2, upkt[0].Token);
// additionalInfo is defined above.
// Encrypt
IDEscrowCiphertext ctext = IDEscrowFunctions.VerifiableEncrypt(ieParam3, pub, tokenID, Cx2, x2, tildeO2, additionalInfo);
// Verify
Assert.IsTrue(IDEscrowFunctions.Verify(ieParam3, ctext, tokenID, pub, Cx2));
// Decrypt
GroupElement PE = IDEscrowFunctions.Decrypt(ieParam3, ctext, priv);
Assert.IsTrue(PE.Equals(ieParam3.Ge.Exponentiate(x2))); // Ensure PE == (ge)^x2
}