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mke_encode_decode

using System;
using System.Text;

namespace MTE {
  class demoCsMke {
    // The timestamp window and sequencing window are hard coded for this
    // demo.
    private const UInt64 timestampWindow = 1;
    private const Int32 sequenceWindow = 0;

    static int Main(string[] args) {
      // Status.
      MteStatus status = MteStatus.mte_status_success;

      // Options.
      MteDrbgs drbg;
      int tokBytes;
      MteVerifiers verifiers;
      MteCiphers cipher;
      MteHashes hash;

      // Initialize MTE license. If a license code is not required (e.g., trial
      // mode), this can be skipped. This demo attempts to load the license
      // info from the environment if required.
      MteBase baseObj = new MteBase();
      if (!baseObj.InitLicense("YOUR_COMPANY", "YOUR_LICENSE")) {
        string company = Environment.GetEnvironmentVariable("MTE_COMPANY");
        string license = Environment.GetEnvironmentVariable("MTE_LICENSE");
        if (company == null || license == null ||
            !baseObj.InitLicense(company, license)) {
          status = MteStatus.mte_status_license_error;
          Console.Error.WriteLine("License init error ({0}): {1}",
                                  baseObj.GetStatusName(status),
                                  baseObj.GetStatusDescription(status));
          return (int)status;
        }
      }

      // Get the input data.
      Console.Write("Enter the data to encode> ");
      string input = Console.ReadLine();

      // Get the personalization string.
      Console.Write("Enter the personalization> ");
      string personal = Console.ReadLine();

      // Set up the options to use the buildtime options if the library is built
      // for that; otherwise prompt for the options.
      if (baseObj.HasRuntimeOpts()) {
        // Get the DRBG.
        Console.Write("DRBGs:");
        for (int i = 1; i < baseObj.GetDrbgsCount(); ++i) {
          Console.Write(" {0}", baseObj.GetDrbgsName((MteDrbgs)i));
        }
        Console.WriteLine();
        Console.Write("Enter the DRBG> ");
        drbg = baseObj.GetDrbgsAlgo(Console.ReadLine());

        // Get the token size.
        Console.Write("Enter the token size in bytes> ");
        tokBytes = Convert.ToInt32(Console.ReadLine());

        // Get the verifiers.
        Console.Write("Verifiers:");
        for (int i = 0; i < baseObj.GetVerifiersCount(); ++i) {
          Console.Write(" {0}", baseObj.GetVerifiersName((MteVerifiers)i));
        }
        Console.WriteLine();
        Console.Write("Enter the verifiers> ");
        verifiers = baseObj.GetVerifiersAlgo(Console.ReadLine());

        // Get the cipher.
        Console.Write("Ciphers:");
        for (int i = 1; i < baseObj.GetCiphersCount(); ++i) {
          Console.Write(" {0}", baseObj.GetCiphersName((MteCiphers)i));
        }
        Console.WriteLine();
        Console.Write("Enter the cipher> ");
        cipher = baseObj.GetCiphersAlgo(Console.ReadLine());

        // Get the hash.
        Console.Write("Hashes:");
        for (int i = 1; i < baseObj.GetHashesCount(); ++i) {
          Console.Write(" {0}", baseObj.GetHashesName((MteHashes)i));
        }
        Console.WriteLine();
        Console.Write("Enter the hash> ");
        hash = baseObj.GetHashesAlgo(Console.ReadLine());
      } else {
        drbg = baseObj.GetDefaultDrbg();
        tokBytes = baseObj.GetDefaultTokBytes();
        verifiers = baseObj.GetDefaultVerifiers();
        cipher = baseObj.GetDefaultCipher();
        hash = baseObj.GetDefaultHash();
      }

      // Create all-zero entropy for this demo. The nonce will also be set to 0.
      // This should never be done in real applications.
      int entropyBytes = baseObj.GetDrbgsEntropyMinBytes(drbg);
      byte[] entropy = new byte[entropyBytes];

      // Create the Encoder.
      MteMkeEnc encoder = new MteMkeEnc(drbg,
                                        tokBytes,
                                        verifiers,
                                        cipher,
                                        hash);
      encoder.SetEntropy(entropy);
      encoder.SetNonce(0);
      status = encoder.Instantiate(personal);
      if (status != MteStatus.mte_status_success) {
        Console.Error.WriteLine("Encoder instantiate error ({0}): " +
                                encoder.GetStatusDescription(status),
                                encoder.GetStatusName(status));
        return (int)status;
      }

      // Encode the input.
      string encoded = encoder.EncodeB64(input, out status);
      if (status != MteStatus.mte_status_success) {
        Console.Error.WriteLine("Encode error ({0}): {1}",
                                encoder.GetStatusName(status),
                                encoder.GetStatusDescription(status));
        return (int)status;
      }

      // Display the encoded message.
      Console.WriteLine("Base64 message: {0}", encoded);

      // Create the Decoder.
      MteMkeDec decoder = new MteMkeDec(drbg,
                                        tokBytes,
                                        verifiers,
                                        cipher,
                                        hash,
                                        timestampWindow,
                                        sequenceWindow);
      decoder.SetEntropy(entropy);
      decoder.SetNonce(0);
      status = decoder.Instantiate(personal);
      if (status != MteStatus.mte_status_success) {
        Console.Error.WriteLine("Decoder instantiate error ({0}): " +
                                decoder.GetStatusDescription(status),
                                decoder.GetStatusName(status));
        return (int)status;
      }

      // Decode the message.
      string decoded = decoder.DecodeStrB64(encoded, out status);
      if (decoder.StatusIsError(status)) {
        Console.Error.WriteLine("Decode error ({0}): {1}",
                                decoder.GetStatusName(status),
                                decoder.GetStatusDescription(status));
        return (int)status;
      } else if (status != MteStatus.mte_status_success) {
        Console.Error.WriteLine("Decode warning ({0}): {1}",
                                decoder.GetStatusName(status),
                                decoder.GetStatusDescription(status));
      }

      // Output the decoded data.
      Console.WriteLine("Decoded data: {0}", decoded);

      // Compare the decoded data against the original data.
      if (decoded == input) {
        Console.WriteLine("The original data and decoded data match.");
      } else {
        Console.WriteLine("The original data and decoded data DO NOT match.");
        return -1;
      }

      // Success.
      return 0;
    }
  }
}