//Verify S3 message public bool VerifyS3Message(byte[] s3Message) { //Convert S3 message from byte array into the compatible structure object S3MessageObj = new DataStructs.SIGMA_S3_MESSAGE(); Utils.ByteArrayToStructure(s3Message, ref S3MessageObj); DataStructs.SIGMA_S3_MESSAGE S3Message = (DataStructs.SIGMA_S3_MESSAGE)S3MessageObj; //Locate the data index in the message int dataInd = Marshal.SizeOf(typeof(DataStructs.SIGMA_S3_MESSAGE)) - 1 + 32; //Copy S3 message data from the received message into the S3 strucure data field S3Message.data = new byte[s3Message.Length - dataInd]; Array.Copy(s3Message, dataInd, S3Message.data, 0, S3Message.data.Length); //Prepare data for HMAC byte[] dataForHmac = new byte[s3Message.Length - S3Message.S3Icv.Length]; Array.Copy(s3Message, S3Message.S3Icv.Length, dataForHmac, 0, dataForHmac.Length); //Verify HMAC CdgResult retStat = CdgResult.CdgValid; CdgStatus status; status = CryptoDataGenWrapper_1_1.VerifyHmac(dataForHmac, dataForHmac.Length, S3Message.S3Icv, DataStructs.SIGMA_MAC_LEN, SMK, DataStructs.SIGMA_SMK_LENGTH, ref retStat); if (status != CdgStatus.CdgStsOk || retStat != CdgResult.CdgValid) { return(false); } //Check whether BK exists in the signed message, as a part of the S3 message validation byte[] GaGbSig = new byte[DataStructs.EPID_SIG_LEN]; if (!DoesBKExist(S3Message, ref GaGbSig)) { return(false); } //groupCert contains the SIGMA1_0 certificate for the specific EPID group ID byte[] groupCert = Utils.GetSpecificEpidCertificate_SIGMA_1_0((uint)groupID); //epidParamsCert contains the mathematic parameters byte[] epidParamsData = File.ReadAllBytes(DataStructs.PRODUCTION_SIGNED_BIN_PARAMS_CERT_FILE); //Verify message. In case that a revocation list is used - the dll function will also check that the platform was not revoked. status = CryptoDataGenWrapper_1_1.MessageVerifyPch(groupCert, groupCert.Length, epidParamsData, GaGb, GaGb.Length, null, 0, GaGbSig, GaGbSig.Length, out retStat, null); if (status != CdgStatus.CdgStsOk || retStat != CdgResult.CdgValid) { return(false); } return(true); }
private bool validateSignature(byte[] adaptedMessage, byte[] signature) { //groupCert contains the SIGMA1_0 certificate for the specific EPID group ID byte[] groupCert = Utils.GetSpecificEpidCertificate_SIGMA_1_0((uint)groupID); //epidParamsCert contains the mathematic parameters byte[] epidParamsCert = File.ReadAllBytes(DataStructs.DEBUG_SIGNED_BIN_PARAMS_CERT_FILE); // taskInfoArray is a data structure defined in the DAL implementation. It is prepended to the message by DAL prior to signing, // and so has to be prepened by us prior to verification byte[] taskInfoArray = Utils.StructureToByteArray(DataStructs.GetTaskInfo()); byte[] infoNonceMessage = new byte[taskInfoArray.Length + adaptedMessage.Length]; //TaskInfo || Nonce || Message taskInfoArray.CopyTo(infoNonceMessage, 0); //concatenate the info to infoNonceMessage adaptedMessage.CopyTo(infoNonceMessage, taskInfoArray.Length); //concatenate the adapted message(including the nonce) to infoNonceMessage //Verify the signature //When we call the MessageVerifyPch function, we can send //baseName - the basename that will be signed as part of the signature //privateKeyRevList - list of the platforms that were revoked based on the platform’s private key //SignatureRevList - list of the platforms that were revoked based on the signature generated by the platform //GroupRevList - list of the EPID groups that were revoked based on the group public key //as parameters. CdgResult retStatus; CdgStatus status = CryptoDataGenWrapper_1_1.MessageVerifyPch(groupCert, groupCert.Length, epidParamsCert, infoNonceMessage, infoNonceMessage.Length, null, 0, signature, signature.Length, out retStatus, null, null, null); if (status != CdgStatus.CdgStsOk) { return(false); } else if (retStatus != CdgResult.CdgValid) { return(false); } else { return(true); } }
public void handleClientComm(object client) { try { TcpClient tcpClient = (TcpClient)client; Socket socket = tcpClient.Client; clientConnected = socket.Connected; while (clientConnected) { byte[] dataSize = new byte[4]; int received, size, total, dataLeft; //receive adapted message(message prepared for verification) received = socket.Receive(dataSize, 0, 4, 0); size = BitConverter.ToInt32(dataSize, 0); total = 0; dataLeft = size; byte[] adaptedMessage = new byte[size]; while (total < size) { received = socket.Receive(adaptedMessage, total, dataLeft, 0); if (received == 0) { break; } total += received; dataLeft -= received; } //receive signature received = socket.Receive(dataSize, 0, 4, 0); size = BitConverter.ToInt32(dataSize, 0); total = 0; dataLeft = size; byte[] signature = new byte[size]; while (total < size) { received = socket.Receive(signature, total, dataLeft, 0); if (received == 0) { break; } total += received; dataLeft -= received; } //receive EPID groupID byte[] groupIDByteArray = new byte[4]; socket.Receive(groupIDByteArray, 0, 4, 0); int groupID = Utils.ByteArrayToInt(groupIDByteArray); //groupCert contains the SIGMA1_0 certificate for the specific EPID group ID byte[] groupCert = Utils.GetSpecificEpidCertificate_SIGMA_1_0((uint)groupID); //epidParamsCert contains the mathematic parameters byte[] epidParamsCert = File.ReadAllBytes(DataStructs.DEBUG_SIGNED_BIN_PARAMS_CERT_FILE); // taskInfoArray is a data structure defined in the DAL implementation. It is prepended to the message by DAL prior to signing, // and so has to be prepended by us prior to verification byte[] taskInfoArray = Utils.StructureToByteArray(DataStructs.GetTaskInfo()); byte[] infoNonceMessage = new byte[taskInfoArray.Length + adaptedMessage.Length]; //TaskInfo || Nonce || Message taskInfoArray.CopyTo(infoNonceMessage, 0); //concatenate the info to infoNonceMessage adaptedMessage.CopyTo(infoNonceMessage, taskInfoArray.Length); //concatenate the adapted message(including the nonce) to infoNonceMessage //Verify the signature //When we call the MessageVerifyPch function, we can send //baseName - the basename that will be signed as part of the signature //privateKeyRevList - list of the platforms that were revoked based on the platform’s private key //SignatureRevList - list of the platforms that were revoked based on the signature generated by the platform //GroupRevList - list of the EPID groups that were revoked based on the group public key //as parameters. CdgResult retStatus; CdgStatus status = CryptoDataGenWrapper_1_1.MessageVerifyPch(groupCert, groupCert.Length, epidParamsCert, infoNonceMessage, infoNonceMessage.Length, null, 0, signature, signature.Length, out retStatus, null, null, null); int res; if (status != CdgStatus.CdgStsOk) { res = ERROR; } else if (retStatus != CdgResult.CdgValid) { res = VERIFYNG_FAILED; } else { res = VERIFYNG_SUCCESS; } byte[] result = new byte[4]; result = BitConverter.GetBytes(res); //Send the signature verification result to the client socket.Send(result); } Console.WriteLine("EPID Signing Sample Client disconnected.\n"); } catch (Exception ex) { Console.WriteLine(ex.Message); } }