private void Dispose(bool Disposing)
{
// note: digest is disposed of by hmac
if (!_isDisposed && Disposing)
{
try
{
if (_shaHmac != null)
{
_shaHmac.Dispose();
_shaHmac = null;
}
}
finally
{
_isDisposed = true;
}
}
}
/// <summary>
/// Initialize the class
/// <para>When using this constructor, you must call <see cref="Initialize(KeyParams)"/> before processing.</para>
/// </summary>
///
/// <param name="DisposeEngine">Dispose of digest engine when <see cref="Dispose()"/> on this class is called</param>
public SHA512HMAC(bool DisposeEngine = true)
{
_shaDigest = new SHA512();
_shaHmac = new HMAC(_shaDigest, DisposeEngine);
}
/// <summary>
/// Initialize the class and working variables.
/// <para>When this constructor is used, <see cref="Initialize(KeyParams)"/> is called automatically.</para>
/// </summary>
///
/// <param name="Key">HMAC Key; passed to HMAC Initialize() through constructor</param>
/// <param name="DisposeEngine">Dispose of digest engine when <see cref="Dispose()"/> on this class is called</param>
///
/// <exception cref="CryptoMacException">Thrown if a null Key is used</exception>
public SHA512HMAC(byte[] Key, bool DisposeEngine = true)
{
if (Key == null)
throw new CryptoMacException("SHA512HMAC:Ctor", "Key can not be null!", new ArgumentNullException());
_shaDigest = new SHA512();
_shaHmac = new HMAC(_shaDigest, Key, DisposeEngine);
_isInitialized = true;
}
/// <summary>
/// Initialize the class
/// <para>When using this constructor, you must call <see cref="Initialize(KeyParams)"/> before processing.</para>
/// </summary>
///
/// <param name="DisposeEngine">Dispose of digest engine when <see cref="Dispose()"/> on this class is called</param>
public SHA256HMAC(bool DisposeEngine = true)
{
_shaDigest = new SHA256();
_shaHmac = new HMAC(_shaDigest, DisposeEngine);
}
/// <summary>
/// Test the StreamMac class implementation
/// <para>Throws an Exception on failure</</para>
/// </summary>
public static void StreamMacTest()
{
byte[] data;
byte[] key;
MemoryStream instrm;
MemoryStream outstrm = new MemoryStream();
using (KeyGenerator kg = new KeyGenerator())
{
data = kg.GetBytes(512);
key = kg.GetBytes(64);
}
// data to digest
instrm = new MemoryStream(data);
byte[] code1;
byte[] code2;
using (StreamMac sm = new StreamMac(new SHA512HMAC(key)))
{
sm.Initialize(instrm);
code1 = sm.ComputeMac();
}
using (HMAC hm = new HMAC(new SHA512()))
{
hm.Initialize(new KeyParams(key));
code2 = hm.ComputeMac(data);
}
// compare the hash codes
if (!Compare.AreEqual(code1, code2))
throw new Exception();
}
/// <remarks>
/// Create keying material using a two stage generator
/// </remarks>
private byte[] GetBlock()
{
// generate seed; 2x input block per NIST sp800-90b
byte[] seed = _seedEngine.GetBytes((_hashEngine.BlockSize * 2));
if (_hashEngine.GetType().Equals(typeof(SHA512)) || _hashEngine.GetType().Equals(typeof(SHA256)))
{
// hmac key size is digest hash size: rfc 2104
byte[] key = _seedEngine.GetBytes(_hashEngine.DigestSize);
// set hmac to *not* dispose of underlying digest
using (HMAC mac = new HMAC(_hashEngine, key, false))
return mac.ComputeMac(seed);
}
else
{
// other implemented digests do not require hmac
return _hashEngine.ComputeHash(seed);
}
}
private void HMACTest(IDigest Digest, String[] Expected, byte[] TruncExpected)
{
HMAC mac = new HMAC(Digest);
byte[] macV2 = new byte[mac.DigestSize];
for (int i = 0; i != _macKeys.Length; i++)
{
mac.Initialize(new KeyParams(_macKeys[i]));
byte[] mData = HexConverter.Decode(_macData[i]);
byte[] macV = new byte[mac.DigestSize];
mac.BlockUpdate(mData, 0, mData.Length);
mac.DoFinal(macV, 0);
if (Compare.AreEqual(HexConverter.Decode(Expected[i]), macV) == false)
throw new Exception("Keccak HMAC: Expected hash is not equal! Expected: " + Expected[i] + " Received: " + HexConverter.ToString(macV));
}
// test truncated keys
mac = new HMAC(Digest);
mac.Initialize(new KeyParams(_truncKey));
mac.BlockUpdate(_truncData, 0, _truncData.Length);
mac.DoFinal(macV2, 0);
for (int i = 0; i != TruncExpected.Length; i++)
{
if (macV2[i] != TruncExpected[i])
throw new Exception("Keccak HMAC: Expected hash is not equal!");
}
}
private void MacTest(byte[] Key, byte[] Input, byte[] Out256, byte[] Out512)
{
byte[] hash = new byte[32];
byte[] trnHash;
// test 1: HMAC interface
HMAC hmac1 = new HMAC(new SHA256());
hmac1.Initialize(new KeyParams(Key));
hash = hmac1.ComputeMac(Input);
// truncated output, test case #5
if (Out256.Length != 32)
{
trnHash = new byte[Out256.Length];
Buffer.BlockCopy(hash, 0, trnHash, 0, Out256.Length);
if (!Compare.AreEqual(Out256, trnHash))
throw new Exception("SHA256HMAC is not equal! Expected: " + HexConverter.ToString(Out256) + " Received: " + HexConverter.ToString(trnHash));
}
else
{
if (!Compare.AreEqual(Out256, hash))
throw new Exception("SHA256HMAC is not equal! Expected: " + HexConverter.ToString(Out256) + " Received: " + HexConverter.ToString(hash));
}
// test 2: 256 hmac
using (SHA256HMAC hmac2 = new SHA256HMAC())
{
hmac2.Initialize(new KeyParams(Key));
hash = hmac2.ComputeMac(Input);
}
if (Out256.Length != 32)
{
trnHash = new byte[Out256.Length];
Buffer.BlockCopy(hash, 0, trnHash, 0, Out256.Length);
if (!Compare.AreEqual(Out256, trnHash))
throw new Exception("SHA256HMAC is not equal! Expected: " + HexConverter.ToString(Out256) + " Received: " + HexConverter.ToString(trnHash));
}
else
{
if (!Compare.AreEqual(Out256, hash))
throw new Exception("SHA256HMAC is not equal! Expected: " + HexConverter.ToString(Out256) + " Received: " + HexConverter.ToString(hash));
}
hash = new byte[32];
// test 3: HMAC interface
hmac1 = new HMAC(new SHA512());
hmac1.Initialize(new KeyParams(Key));
hash = hmac1.ComputeMac(Input);
if (Out512.Length != 64)
{
trnHash = new byte[Out512.Length];
Buffer.BlockCopy(hash, 0, trnHash, 0, Out512.Length);
if (!Compare.AreEqual(Out512, trnHash))
throw new Exception("SHA512HMAC is not equal! Expected: " + HexConverter.ToString(Out512) + " Received: " + HexConverter.ToString(trnHash));
}
else
{
if (!Compare.AreEqual(Out512, hash))
throw new Exception("SHA512HMAC is not equal! Expected: " + HexConverter.ToString(Out512) + " Received: " + HexConverter.ToString(hash));
}
// test 4: 256 hmac
using (SHA512HMAC hmac3 = new SHA512HMAC())
{
hmac3.Initialize(new KeyParams(Key));
hash = hmac3.ComputeMac(Input);
}
if (Out512.Length != 64)
{
trnHash = new byte[Out512.Length];
Buffer.BlockCopy(hash, 0, trnHash, 0, Out512.Length);
if (!Compare.AreEqual(Out512, trnHash))
throw new Exception("SHA512HMAC is not equal! Expected: " + HexConverter.ToString(Out512) + " Received: " + HexConverter.ToString(trnHash));
}
else
{
if (!Compare.AreEqual(Out512, hash))
throw new Exception("SHA512HMAC is not equal! Expected: " + HexConverter.ToString(Out512) + " Received: " + HexConverter.ToString(hash));
}
}