(C# UWP/WinRT) Duplicate Java HMAC-SHA1 using Chilkat

This example uses Chilkat to produce the same results as this Java code:

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.NoSuchAlgorithmException;

public void hmacSignatureExample() throws NoSuchAlgorithmException,
InvalidKeyException {

final String method = "POST";
final Long epoch = 1456765639015L; // Hardcoding for this example
final String uri = "/api/v5/policy/1234567890";
final String newline = "\n";

final String privateKey = "qwfvUeVRWAwyjlAzGivefFPTg+m6QtBPmDVv7Ra
/u7K3UuVVRhrZ/qc8EPh8IGJatuxsWD4EX+D9qE/eVvLTpw==";
final String publicKey = "16baedbe244b6c063968850716afb319a";

// Prepare the signature
final String plainText = method + newline + epoch + newline + uri + newline;

// Hash the plaintext with the private key
final byte[] keyBytes = privateKey.getBytes();
final Key key = new SecretKeySpec(keyBytes, 0, keyBytes.length, "HmacSHA1");
final Mac mac = Mac.getInstance("HmacSHA1");
mac.init(key);
String signatureHash = new String(Hex.encodeHex(mac.doFinal(plainText.
getBytes())));

// Prefix with public key
signatureHash = publicKey + ":" + signatureHash;

// Base64 encode to produce AUTHORIZATION
final String authorization = new String(Base64.encodeBase64(signatureHash.
getBytes()));
}

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

bool success;

// This is clearly in base64 encoding.
string privateKey = "qwfvUeVRWAwyjlAzGivefFPTg+m6QtBPmDVv7Ra/u7K3UuVVRhrZ/qc8EPh8IGJatuxsWD4EX+D9qE/eVvLTpw==";

// This is clearly in the hex encoding.
string publicKey = "16baedbe244b6c063968850716afb319a";

string plainText = "POST\n1456765639015\n/api/v5/policy/1234567890\n";

Chilkat.Crypt2 crypt = new Chilkat.Crypt2();

// We want HMAC-SHA1.
crypt.MacAlgorithm = "HMAC";
crypt.HashAlgorithm = "SHA1";

// The Java code (above) is literally using the us-ascii chars of the base64 string as the HMAC key.
// (It is NOT using the base64 decoded bytes.)
crypt.SetMacKeyEncoded(privateKey,"us-ascii");

// We want our HMAC-SHA1 output to be a hex string.
crypt.EncodingMode = "hex_lower";

string hmacHex = crypt.MacStringENC(plainText);

Debug.WriteLine(hmacHex);

// The expected result is: dd3e8440f6b550f152156ea5e12d3e20b262adae

Chilkat.StringBuilder sbSignatureHash = new Chilkat.StringBuilder();
sbSignatureHash.Append(publicKey);
sbSignatureHash.Append(":");
sbSignatureHash.Append(hmacHex);

string authorization = sbSignatureHash.GetEncoded("base64","utf-8");
Debug.WriteLine("Authorization: " + authorization);

// The expected result is:  MTZiYWVkYmUyNDRiNmMwNjM5Njg4NTA3MTZhZmIzMTlhOmRkM2U4NDQwZjZiNTUwZjE1MjE1NmVhNWUxMmQzZTIwYjI2MmFkYWU=