private static CommitmentPrivateValues PresentUProveToken(IssuerParameters ip, UProveKeyAndToken upkt, byte[][] attributes, int[] disclosed, int[] committed, byte[] message, byte[] scope, IDevice device, byte[] deviceMessage)
{
WriteLine("Presenting one token");
// the returned commitment randomizer (to be used by an external proof module)
CommitmentPrivateValues cpv;
// generate the presentation proof
string token = ip.Serialize <UProveToken>(upkt.Token);
ProverPresentationProtocolParameters pppp = new ProverPresentationProtocolParameters(ip, disclosed, message, upkt, attributes);
pppp.Committed = committed;
// if a scope is defined, we use the first attribute to derive a scope exclusive pseudonym
pppp.PseudonymAttributeIndex = (scope == null ? 0 : 1);
pppp.PseudonymScope = scope;
if (device != null)
{
pppp.SetDeviceData(deviceMessage, device.GetPresentationContext());
}
pppp.KeyAndToken = upkt;
pppp.Attributes = attributes;
string proof = ip.Serialize <PresentationProof>(PresentationProof.Generate(pppp, out cpv));
// verify the presentation proof
VerifierPresentationProtocolParameters vppp = new VerifierPresentationProtocolParameters(ip, disclosed, message, ip.Deserialize <UProveToken>(token));
vppp.Committed = committed;
// if a scope is defined, we use the first attribute to derive a scope exclusive pseudonym
vppp.PseudonymAttributeIndex = (scope == null ? 0 : 1);
vppp.PseudonymScope = scope;
vppp.DeviceMessage = deviceMessage;
ip.Deserialize <PresentationProof>(proof).Verify(vppp);
return(cpv);
}
/// <summary>
/// first method to call - Initializes the ProverProof by generating the PresentationProof
/// </summary>
/// <param name="ip">IssuerParameter from the Issuer of the given token</param>
/// <param name="attributes">Attributes which are included in the given token</param>
/// <param name="proofRequirements">Necessary informations for creating the proofs (e.g. disclosedAttributes)</param>
/// <param name="tokenWithKey">Token for which the proof will be done</param>
/// <param name="supportedDateAttributes">If there is a RangeProof done, all date attributes where treated and formated especially</param>
/// <param name="devicePresentationContext">If there was a device involved during the token generation, the context from the device is needed to generate the
/// PresentationProof as well</param>
/// <returns>returns the proof for the given token as json object or an error</returns>
public string Init(IssuerParameters ip, List <BasicClaim> attributes, ProofRequirements proofRequirements,
UProveKeyAndToken tokenWithKey, List <string> supportedDateAttributes,
IDevicePresentationContext devicePresentationContext)
{
try
{
LogService.Log(LogService.LogType.Info, "ProverProof - init called");
this.ip = ip;
this.proofRequirements = proofRequirements;
ci.CreateBase64ForAttributeList(attributes, supportedDateAttributes, out rangeProofProperties);
attributesToInclude = ci.ConvertAttributeListToBase64ByteArray(attributes);
pppp = new ProverPresentationProtocolParameters(this.ip, proofRequirements.disclosedAttributes,
proofRequirements.message, tokenWithKey, attributesToInclude);
pppp.Committed = proofRequirements.committedAttributes;
//// TODO
//// if a scope is defined, we use the first attribute to derive a scope exclusive pseudonym
//pppp.PseudonymAttributeIndex = (proofRequirements.scope == null ? 0 : 1);
//pppp.PseudonymScope = proofRequirements.scope;
// add device presentation context to the provers presentation context
if (this.ip.IsDeviceSupported && devicePresentationContext != null)
{
pppp.SetDeviceData(proofRequirements.deviceMessage, devicePresentationContext);
}
// generate proof
PresentationProof pProof = PresentationProof.Generate(pppp, out cpv);
LogService.Log(LogService.LogType.Info, "ProverProof - init presentation proof generated");
proof = parser.ParseJsonToObject <Proof>(this.ip.Serialize <PresentationProof>(pProof));
proof.requirements = proofRequirements;
string proofJson = parser.ParseObjectToJson(proof);
LogService.Log(LogService.LogType.Info, "ProverProof - proof created: " + proofJson);
return(proofJson);
}
catch (Exception e)
{
LogService.Log(LogService.LogType.FatalError, "ProverProof - Error during prover setup.", e);
throw new CommunicationException("ProverProof - Error during ProverProof init; " + e);
}
}