public static void CheckKey(byte[] key)
{
if (key.Length != 32)
{
throw new ArgumentException("Poly1305 key must be 256 bits.");
}
Poly1305KeyGenerator.checkMask(key[19], 15);
Poly1305KeyGenerator.checkMask(key[23], 15);
Poly1305KeyGenerator.checkMask(key[27], 15);
Poly1305KeyGenerator.checkMask(key[31], 15);
Poly1305KeyGenerator.checkMask(key[20], 252);
Poly1305KeyGenerator.checkMask(key[24], 252);
Poly1305KeyGenerator.checkMask(key[28], 252);
}
private void testKeyGenerator()
{
CipherKeyGenerator gen = new Poly1305KeyGenerator();
gen.Init(new KeyGenerationParameters(new SecureRandom(), 256));
byte[] k = gen.GenerateKey();
if (k.Length != 32)
{
Fail("Poly1305 key should be 256 bits.");
}
try
{
Poly1305KeyGenerator.CheckKey(k);
} catch (ArgumentException)
{
Fail("Poly1305 key should be Clamped on generation.");
}
byte[] k2 = new byte[k.Length];
Array.Copy(k, 0, k2, 0, k2.Length);
Poly1305KeyGenerator.Clamp(k);
if (!Arrays.AreEqual(k, k2))
{
Fail("Poly1305 key should be Clamped on generation.");
}
try
{
k2[19] = (byte)0xff;
Poly1305KeyGenerator.CheckKey(k2);
Fail("UnClamped key should fail check.");
} catch (ArgumentException)
{
// Expected
}
}
private void testInit()
{
CipherKeyGenerator gen = new Poly1305KeyGenerator();
gen.Init(new KeyGenerationParameters(new SecureRandom(), 256));
byte[] k = gen.GenerateKey();
IMac poly = new Poly1305(new AesFastEngine());
poly.Init(new ParametersWithIV(new KeyParameter(k), new byte[16]));
try
{
poly.Init(new ParametersWithIV(new KeyParameter(k), new byte[15]));
Fail("16 byte nonce required");
} catch (ArgumentException)
{
// Expected
}
try
{
byte[] k2 = new byte[k.Length - 1];
Array.Copy(k, 0, k2, 0, k2.Length);
poly.Init(new ParametersWithIV(new KeyParameter(k2), new byte[16]));
Fail("32 byte key required");
} catch (ArgumentException)
{
// Expected
}
try
{
k[19] = (byte)0xFF;
poly.Init(new ParametersWithIV(new KeyParameter(k), new byte[16]));
Fail("UnClamped key should not be accepted.");
} catch (ArgumentException)
{
// Expected
}
}
private void testReset()
{
CipherKeyGenerator gen = new Poly1305KeyGenerator();
gen.Init(new KeyGenerationParameters(new SecureRandom(), 256));
byte[] k = gen.GenerateKey();
byte[] m = new byte[10000];
byte[] check = new byte[16];
byte[] output = new byte[16];
// Generate baseline
IMac poly = new Poly1305(new AesFastEngine());
poly.Init(new ParametersWithIV(new KeyParameter(k), new byte[16]));
poly.BlockUpdate(m, 0, m.Length);
poly.DoFinal(check, 0);
// Check reset after doFinal
poly.BlockUpdate(m, 0, m.Length);
poly.DoFinal(output, 0);
if (!Arrays.AreEqual(check, output))
{
Fail("Mac not reset after doFinal");
}
// Check reset
poly.Update((byte)1);
poly.Update((byte)2);
poly.Reset();
poly.BlockUpdate(m, 0, m.Length);
poly.DoFinal(output, 0);
if (!Arrays.AreEqual(check, output))
{
Fail("Mac not reset after doFinal");
}
// Check init resets
poly.Update((byte)1);
poly.Update((byte)2);
poly.Init(new ParametersWithIV(new KeyParameter(k), new byte[16]));
poly.BlockUpdate(m, 0, m.Length);
poly.DoFinal(output, 0);
if (!Arrays.AreEqual(check, output))
{
Fail("Mac not reset after doFinal");
}
}
protected override byte[] engineGenerateKey()
{
byte[] array = base.engineGenerateKey();
Poly1305KeyGenerator.Clamp(array);
return(array);
}
