public bool verifyPseudonym(string messageParam, string verifierScopeParam, PseudonymComposite pseudonym, string sessionID)
{
// we validate the pseudonym here because the U-Prove SDK only supports this while
// validating a presentation proof
cOut.write("verfiyPseudonym()");
VerifySessionId(sessionID);
try
{
DeviceManager dManager = sessionDB[sessionID].deviceManager;
dManager.EnsureDeviceInit();
Pseudonym p = ConvertUtils.convertPseudonymComposite(pseudonym, dManager);
bool scopeExclusive = (verifierScopeParam != null && verifierScopeParam != "null" && verifierScopeParam.Length > 0);
GroupElement baseElement = null;
if (scopeExclusive)
{
baseElement = ProtocolHelper.GenerateScopeElement(dManager.Gq, encoding.GetBytes(verifierScopeParam));
}
else
{
baseElement = dManager.Gd;
}
BigInteger c = dManager.ComputeDeviceChallenge(encoding.GetBytes(messageParam));
// A =?= g^R P^c
return(p.A.Equals(baseElement.Exponentiate(p.R).Multiply(p.P.Exponentiate(c))));
}
catch (Exception e)
{
cOut.write("Exception caught: " + e.Message);
DebugUtils.DebugPrint(e.StackTrace.ToString());
return(false);
}
}
public static Pseudonym convertPseudonymComposite(PseudonymComposite pc, DeviceManager dManager)
{
Pseudonym p = new Pseudonym();
p.A = dManager.Gq.CreateGroupElement(pc.A);
p.P = dManager.Gq.CreateGroupElement(pc.P);
p.R = new BigInteger(1, pc.R);
return p;
}
public static PseudonymComposite convertPseudonym(Pseudonym p)
{
PseudonymComposite pc = new PseudonymComposite();
pc.A = p.A.GetEncoded();
pc.P = p.P.GetEncoded();
pc.R = p.R.ToByteArray();
return pc;
}
public static Pseudonym convertPseudonymComposite(PseudonymComposite pc, DeviceManager dManager)
{
Pseudonym p = new Pseudonym();
p.A = dManager.Gq.CreateGroupElement(pc.A);
p.P = dManager.Gq.CreateGroupElement(pc.P);
p.R = new BigInteger(1, pc.R);
return(p);
}
public static PseudonymComposite convertPseudonym(Pseudonym p)
{
PseudonymComposite pc = new PseudonymComposite();
pc.A = p.A.GetEncoded();
pc.P = p.P.GetEncoded();
pc.R = p.R.ToByteArray();
return(pc);
}
public bool verifyPseudonym(string messageParam, string verifierScopeParam, PseudonymComposite pseudonym, string sessionID)
{
// we validate the pseudonym here because the U-Prove SDK only supports this while
// validating a presentation proof
cOut.write("verfiyPseudonym()");
VerifySessionId(sessionID);
try
{
DeviceManager dManager = sessionDB[sessionID].deviceManager;
dManager.EnsureDeviceInit();
Pseudonym p = ConvertUtils.convertPseudonymComposite(pseudonym, dManager);
bool scopeExclusive = (verifierScopeParam != null && verifierScopeParam != "null" && verifierScopeParam.Length > 0);
GroupElement baseElement = null;
if (scopeExclusive)
{
baseElement = ProtocolHelper.GenerateScopeElement(dManager.Gq, encoding.GetBytes(verifierScopeParam));
}
else
{
baseElement = dManager.Gd;
}
BigInteger c = dManager.ComputeDeviceChallenge(encoding.GetBytes(messageParam));
// A =?= g^R P^c
return p.A.Equals(baseElement.Exponentiate(p.R).Multiply(p.P.Exponentiate(c)));
}
catch (Exception e)
{
cOut.write("Exception caught: " + e.Message);
DebugUtils.DebugPrint(e.StackTrace.ToString());
return false;
}
}
