public static void BitIndependenceCriterionTest(HashInfo hashInfo)
{
RandomXS r = new RandomXS(0x000000B1u);
Hash hash = hashInfo.Initializer(r.NextValue());
Int32 hashBytes = hashInfo.Length / 8;
Int32 hashBits = hashInfo.Length;
Int32 pageSize = hashBits * hashBits * 4;
Int32 keyBytes = BICT_KEYSBYTES;
Int32 keyBits = keyBytes * 8;
Byte[] key = new Byte[keyBytes];
Double biasFactor = BICT_REPETITIONS / 2.0d;
Int32 step = keyBits / 10;
Console.WriteLine("[[ BIT INDEPENDENCE CRITERION TEST ]]");
Console.Write("Result: ");
Int32[] bins = new Int32[keyBits * pageSize];
for (Int32 keyBit = 0; keyBit < keyBits; ++keyBit)
{
if ((keyBit % step) == 0)
{
Console.Write(".");
}
Int32 pageOffset = keyBit * pageSize;
for (Int32 irep = 0; irep < BICT_REPETITIONS; ++irep)
{
r.NextBytes(key);
Byte[] h1 = hash.ComputeHash(key);
BitsUtilities.FlipBit(key, 0, keyBytes, keyBit);
Byte[] h2 = hash.ComputeHash(key);
Byte[] d = new Byte[hashBytes];
for (Int32 i = 0; i < hashBytes; ++i)
{
d[i] = (Byte)(h1[i] ^ h2[i]);
}
for (Int32 hashBit1 = 0; hashBit1 < hashBits - 1; ++hashBit1)
{
for (Int32 hashBit2 = hashBit1 + 1; hashBit2 < hashBits; ++hashBit2)
{
Int32 x = BitsUtilities.GetBit(d, 0, hashBytes, hashBit1) | (BitsUtilities.GetBit(d, 0, hashBytes, hashBit2) << 1);
++bins[pageOffset + (((hashBit1 * hashBits) + hashBit2) * 4) + x];
}
}
}
}
Double worstBias = 0.0d;
Int32 worstKeyBit = -1;
Int32 worstHashBit1 = -1;
Int32 worstHashBit2 = -1;
for (Int32 hashBit1 = 0; hashBit1 < hashBits - 1; ++hashBit1)
{
for (Int32 hashBit2 = hashBit1 + 1; hashBit2 < hashBits; ++hashBit2)
{
for (Int32 keyBit = 0; keyBit < keyBits; ++keyBit)
{
Int32 binsOffset = (keyBit * pageSize) + ((hashBit1 * hashBits) + hashBit2) * 4;
for (Int32 b = 0; b < 4; ++b)
{
Double c = bins[binsOffset + b] / biasFactor;
Double bias = Math.Abs((c * 2.0d) - 1.0d);
if (bias > worstBias)
{
worstBias = bias;
worstKeyBit = keyBit;
worstHashBit1 = hashBit1;
worstHashBit2 = hashBit2;
}
}
}
}
}
Boolean result = (worstBias <= 0.05d);
Console.WriteLine(result ? " PASSED" : " FAILED");
Console.WriteLine($" - Worst Bias: {(worstBias.Equals(0.0d) ? "Unbiased" : $"{(worstBias * 100.0d):F2}% (Key Bit: {worstKeyBit} | Hash Bit 1: {worstHashBit1} | Hash Bit 2: {worstHashBit2})")}");
}
public static void DifferentialTest(HashInfo hashInfo)
{
RandomXS r = new RandomXS(0x000000B2u);
Int32 hashBytes = hashInfo.Length / 8;
Int32 hashBits = hashInfo.Length;
Console.WriteLine("[[ DIFFERENTIAL TEST ]]");
Console.WriteLine($"Maximum Errors: {DT_MAXIMUMERRORS}");
Boolean resultOverall = true;
for (Int32 i = 0; i < s_ParametersDT.Length; ++i)
{
dynamic p = s_ParametersDT[i];
Int32 keysBytes = p.KeysBytes;
Int32 keysBits = keysBytes * 8;
Byte[] key1 = new Byte[keysBytes];
Byte[] key2 = new Byte[keysBytes];
Int32 bits = p.Bits;
Int32 repetitions = p.Repetitions;
Int32 steps = repetitions / 10;
Double tests = StatsUtilities.ChooseUpToK(keysBits, p.Bits) * repetitions;
Double expectedCollisions = Math.Round(tests / Math.Pow(2.0d, hashBits));
Console.WriteLine($"> Bits: 1-{bits}");
Console.WriteLine($" Repetitions: {repetitions}");
Console.WriteLine($" Tests: {tests:F0}");
Console.WriteLine($" Expected Collisions: {expectedCollisions:F0}");
Console.Write(" Result: ");
Byte[] h2 = new Byte[hashBytes];
UInt64 skipped = 0;
List <Byte[]> diffs = new List <Byte[]>(DT_MAXIMUMERRORS);
for (Int32 j = 0; j < repetitions; ++j)
{
if ((j % steps) == 0)
{
Console.Write((skipped > 0) ? "!" : ".");
}
r.NextBytes(key1);
UnsafeBuffer.BlockCopy(key1, 0, key2, 0, keysBytes);
Hash hash = hashInfo.Initializer(r.NextValue());
Byte[] h1 = hash.ComputeHash(key1);
skipped += DifferentialTestRecursion(diffs, hash, keysBytes, key1, key2, hashBytes, h1, h2, 0, p.Bits);
}
Boolean result = true;
if (skipped > 0)
{
result = false;
Console.WriteLine(" FAILED");
Console.WriteLine(" - Errors Threshold Exceeded");
}
else
{
Int32 ignoredCollisions = DifferentialTestIgnored(diffs, ref result);
Console.WriteLine(result ? " PASSED" : " FAILED");
Console.WriteLine($" - Observed Collisions: {diffs.Count} ({ignoredCollisions} Ignored)");
}
resultOverall &= result;
}
Console.WriteLine($"Test Result: {(resultOverall ? "PASSED" : "FAILED")}");
}
public static void AvalancheTest(HashInfo hashInfo)
{
RandomXS r = new RandomXS(0x000000B0u);
Hash hash = hashInfo.Initializer(r.NextValue());
Int32 hashBytes = hashInfo.Length / 8;
Int32 hashBits = hashInfo.Length;
Console.WriteLine("[[ AVALANCHE TEST ]]");
Boolean resultOverall = true;
for (Int32 i = 0; i < s_ParametersAT.Length; ++i)
{
dynamic p = s_ParametersAT[i];
Int32 keyBytes = p.KeysBytes;
Int32 keyBits = keyBytes * 8;
Byte[] key = new Byte[p.KeysBytes];
Int32 repetitions = p.Repetitions;
Int32 step = repetitions / 10;
Console.WriteLine($"> Keys Length: {keyBytes} Bytes");
Console.WriteLine($" Repetitions: {repetitions}");
Console.Write(" Result: ");
Int32 binsCount = keyBits * hashBits;
Int32[] bins = new Int32[keyBits * hashBits];
for (Int32 j = 0; j < repetitions; ++j)
{
if ((j % step) == 0)
{
Console.Write(".");
}
r.NextBytes(key);
Byte[] h0 = hash.ComputeHash(key);
Int32 binsIndex = 0;
for (Int32 keyBit = 0; keyBit < keyBits; ++keyBit)
{
BitsUtilities.FlipBit(key, 0, keyBytes, keyBit);
Byte[] hi = hash.ComputeHash(key);
BitsUtilities.FlipBit(key, 0, keyBytes, keyBit);
for (Int32 hashBit = 0; hashBit < hashBits; ++hashBit)
{
Byte a = BitsUtilities.GetBit(h0, 0, hashBytes, hashBit);
Byte b = BitsUtilities.GetBit(hi, 0, hashBytes, hashBit);
bins[binsIndex++] += a ^ b;
}
}
}
Double worstBias = 0.0d;
for (Int32 j = 0; j < binsCount; ++j)
{
Double c = (Double)bins[j] / repetitions;
Double bias = Math.Abs((c * 2.0d) - 1.0d);
if (bias > worstBias)
{
worstBias = bias;
}
}
Boolean result = (worstBias <= 0.01d);
Console.WriteLine(result ? " PASSED" : " FAILED");
Console.WriteLine($" - Worst Bias: {(worstBias.Equals(0.0d) ? "Unbiased" : $"{(worstBias * 100.0d):F2}%")}");
resultOverall &= result;
}
Console.WriteLine($"Test Result: {(resultOverall ? "PASSED" : "FAILED")}");
}