/**
* Generate a new instance of an TlsMac.
*
* @param digest The digest to use.
* @param key_block A byte-array where the key for this mac is located.
* @param offset The number of bytes to skip, before the key starts in the buffer.
* @param len The length of the key.
*/
public TlsMac(
IDigest digest,
byte[] key_block,
int offset,
int len)
{
this.mac = new HMac(digest);
KeyParameter param = new KeyParameter(key_block, offset, len);
this.mac.Init(param);
this.seqNo = 0;
}
public string CalculateHMAC(string iPut, string uName,string HMACKey)
{
byte[] array = Encoding.UTF8.GetBytes(iPut + "/" + uName);
byte[] output = new byte[256];
IDigest dig = DigestUtilities.GetDigest("SHA256");
HMac hm = new HMac(dig);
byte[] keyArray = Base32Encoder.Decode(HMACKey);
hm.BlockUpdate(array, 0, array.Length);
hm.Init(new KeyParameter(keyArray, 0, keyArray.Length));
int len = hm.DoFinal(output, 0);
return Base32Encoder.Encode(output);
}
public static string Signature(string httpmethod, string url, string parameterString, string oauthToken)
{
string baseString = httpmethod.ToUpper() + "&" + PercentEncode(url) + "&" + PercentEncode(parameterString);
string signingKey = PercentEncode(consumerSecret) + "&" + PercentEncode(oauthToken);
var sha = new HMac(new Sha1Digest());
sha.Init(new KeyParameter(Encoding.UTF8.GetBytes(signingKey)));
var data = Encoding.UTF8.GetBytes(baseString);
sha.BlockUpdate(data, 0, data.Length);
byte[] result = new byte[20];
sha.DoFinal(result, 0);
return Convert.ToBase64String(result);
}
private static void hmac_hash(IDigest digest, byte[] secret, byte[] seed, byte[] output)
{
HMac mac = new HMac(digest);
KeyParameter param = new KeyParameter(secret);
byte[] a = seed;
int size = digest.GetDigestSize();
int iterations = (output.Length + size - 1) / size;
byte[] buf = new byte[mac.GetMacSize()];
byte[] buf2 = new byte[mac.GetMacSize()];
for (int i = 0; i < iterations; i++)
{
mac.Init(param);
mac.BlockUpdate(a, 0, a.Length);
mac.DoFinal(buf, 0);
a = buf;
mac.Init(param);
mac.BlockUpdate(a, 0, a.Length);
mac.BlockUpdate(seed, 0, seed.Length);
mac.DoFinal(buf2, 0);
Array.Copy(buf2, 0, output, (size * i), System.Math.Min(size, output.Length - (size * i)));
}
}
