/// <summary>
/// Compares plain text input with a computed hash using the configured <c>HashAlgorithm</c>.
/// <seealso cref="IHashProvider.CompareHash"/>
/// </summary>
/// <param name="plaintext"><seealso cref="IHashProvider.CompareHash"/></param>
/// <param name="hashedtext"><seealso cref="IHashProvider.CompareHash"/></param>
/// <returns><seealso cref="IHashProvider.CompareHash"/></returns>
public bool CompareHash(byte[] plaintext, byte[] hashedtext)
{
ArgumentValidation.CheckForNullReference(plaintext, "plainText");
ArgumentValidation.CheckForNullReference(hashedtext, "hashedText");
ArgumentValidation.CheckForZeroBytes(hashedtext, "hashedText");
bool result = false;
byte[] hashedPlainText = null;
byte[] salt = null;
try
{
salt = ExtractSalt(hashedtext);
hashedPlainText = CreateHashWithSalt(plaintext, salt);
}
finally
{
CryptographyUtility.ZeroOutBytes(salt);
}
result = CryptographyUtility.CompareBytes(hashedPlainText, hashedtext);
SecurityCryptoHashCheckEvent.Fire(string.Empty);
if (!result)
{
SecurityCryptoHashCheckFailureEvent.Fire(string.Empty);
}
return(result);
}
/// <summary>
/// Compares plain text input with a computed hash.
/// </summary>
/// <param name="plaintext">The input for which you want to compare the hash to.</param>
/// <param name="hashedtext">The hash value for which you want to compare the input to.</param>
/// <returns><c>true</c> if plainText hashed is equal to the hashedText. Otherwise, <c>false</c>.</returns>
public bool CompareHash(byte[] plaintext, byte[] hashedtext)
{
if (plaintext == null)
{
throw new ArgumentNullException("plainText");
}
if (hashedtext == null)
{
throw new ArgumentNullException("hashedText");
}
if (hashedtext.Length == 0)
{
throw new ArgumentException(Resources.ExceptionByteArrayValueMustBeGreaterThanZeroBytes, "hashedText");
}
bool result = false;
byte[] hashedPlainText = null;
byte[] salt = null;
try
{
try
{
salt = ExtractSalt(hashedtext);
hashedPlainText = CreateHashWithSalt(plaintext, salt);
}
finally
{
CryptographyUtility.ZeroOutBytes(salt);
}
result = CryptographyUtility.CompareBytes(hashedPlainText, hashedtext);
}
catch (Exception e)
{
InstrumentationProvider.FireCyptographicOperationFailed(Resources.HashComparisonFailed, e);
throw;
}
InstrumentationProvider.FireHashComparisonPerformed();
if (!result)
{
InstrumentationProvider.FireHashMismatchDetected();
}
return(result);
}