public static string MakePbkdf2String(this IKeyedHashFunction hash, string input, byte[] salt, int length, int iterationCount)
{
var data = Encoding.UTF8.GetBytes(input);
var result = hash.MakePbkdf2(data, salt, length, iterationCount);
return(Convert.ToBase64String(result));
}
public static bool VerifyPbkdf2String(this IKeyedHashFunction hash, string hashedString, string otherString, string saltString, int iterationCount)
{
var hashed = Convert.FromBase64String(hashedString);
var otherData = Encoding.UTF8.GetBytes(otherString);
var salt = Convert.FromBase64String(saltString);
return(hash.VerifyPbkdf2(hashed, otherData, salt, iterationCount));
}
public static byte[] MakePbkdf2(this IKeyedHashFunction hash, byte[] salt, int length, int iterationCount)
{
var hashKey = hash.Key;
if (hashKey == null || hashKey.Length == 0)
{
throw new InvalidOperationException("Key was not specified for the hash.");
}
return(MakePbkdf2(hash, hashKey, salt, length, iterationCount));
}
public static bool VerifyPbkdf2(this IKeyedHashFunction hash, byte[] hashed, byte[] otherData, byte[] salt, int iterationCount)
{
int length = hashed.Length;
var otherHashed = hash.MakePbkdf2(otherData, salt, length, iterationCount);
if (otherHashed.Length != hashed.Length)
{
return(false);
}
return(ByteArraysEqual(hashed, otherHashed));
}
public static byte[] MakePbkdf2(this IKeyedHashFunction hash, byte[] data, byte[] salt, int length, int iterationCount)
{
hash.Key = data;
int hashLength = hash.HashSize / 8;
if ((hash.HashSize & 7) != 0)
{
hashLength++;
}
int keyLength = length / hashLength;
if (length > (0xFFFFFFFFL * hashLength) || length < 0)
{
throw new ArgumentOutOfRangeException("length");
}
if (length % hashLength != 0)
{
keyLength++;
}
byte[] extendedkey = new byte[salt.Length + 4];
Buffer.BlockCopy(salt, 0, extendedkey, 0, salt.Length);
using (var ms = new MemoryStream()) {
for (int i = 0; i < keyLength; i++)
{
extendedkey[salt.Length] = (byte)(((i + 1) >> 24) & 0xFF);
extendedkey[salt.Length + 1] = (byte)(((i + 1) >> 16) & 0xFF);
extendedkey[salt.Length + 2] = (byte)(((i + 1) >> 8) & 0xFF);
extendedkey[salt.Length + 3] = (byte)(((i + 1)) & 0xFF);
byte[] u = hash.Compute(extendedkey);
Array.Clear(extendedkey, salt.Length, 4);
byte[] f = u;
for (int j = 1; j < iterationCount; j++)
{
u = hash.Compute(u);
for (int k = 0; k < f.Length; k++)
{
f[k] ^= u[k];
}
}
ms.Write(f, 0, f.Length);
Array.Clear(u, 0, u.Length);
Array.Clear(f, 0, f.Length);
}
byte[] dk = new byte[length];
ms.Position = 0;
ms.Read(dk, 0, length);
ms.Position = 0;
for (long i = 0; i < ms.Length; i++)
{
ms.WriteByte(0);
}
Array.Clear(extendedkey, 0, extendedkey.Length);
return(dk);
}
}
public static byte[] MakePbkdf2(this IKeyedHashFunction hash, byte[] data, byte[] salt, int length)
{
return(MakePbkdf2(hash, data, salt, length, DefaultIterationCount));
}
public static string MakePbkdf2String(this IKeyedHashFunction hash, string input, byte[] salt, int length)
{
return(MakePbkdf2String(hash, input, salt, length, DefaultIterationCount));
}
public static string MakePbkdf2String(this IKeyedHashFunction hash, string input, string salt, int length, int iterationCount)
{
return(hash.MakePbkdf2String(input, Convert.FromBase64String(salt), length, iterationCount));
}
public static bool VerifyPbkdf2String(this IKeyedHashFunction hash, string hashedString, string otherString, string saltString)
{
return(VerifyPbkdf2String(hash, hashedString, otherString, saltString, DefaultIterationCount));
}
public static bool VerifyPbkdf2String(this IKeyedHashFunction hash, string hashedString, string otherString, byte[] salt, int iterationCount)
{
return(hash.VerifyPbkdf2String(hashedString, otherString, Convert.ToBase64String(salt), iterationCount));
}
public static bool VerifyPbkdf2(this IKeyedHashFunction hash, byte[] hashed, byte[] otherData, byte[] salt)
{
return(VerifyPbkdf2(hash, hashed, otherData, salt, DefaultIterationCount));
}
