internal static HashAlgorithm CreateHashAlgorithm(string digestMethod)
{
object algorithmObject = CryptoAlgorithms.GetAlgorithmFromConfig(digestMethod);
if (algorithmObject != null)
{
HashAlgorithm hashAlgorithm = algorithmObject as HashAlgorithm;
if (hashAlgorithm != null)
{
return(hashAlgorithm);
}
throw DiagnosticUtility.ExceptionUtility.ThrowHelperWarning(new MessageSecurityException(SR.Format(SR.CustomCryptoAlgorithmIsNotValidHashAlgorithm, digestMethod)));
}
switch (digestMethod)
{
case SecurityAlgorithms.Sha1Digest:
return(SHA1.Create());
case SecurityAlgorithms.Sha256Digest:
return(SHA256.Create());
default:
throw DiagnosticUtility.ExceptionUtility.ThrowHelperWarning(new MessageSecurityException(SR.Format(SR.UnsupportedCryptoAlgorithm, digestMethod)));
}
}
internal static HashAlgorithm CreateHashForAsymmetricSignature(string signatureMethod)
{
object algorithmObject = CryptoAlgorithms.GetAlgorithmFromConfig(signatureMethod);
if (algorithmObject != null)
{
HashAlgorithm hashAlgorithm;
SignatureDescription signatureDescription = algorithmObject as SignatureDescription;
if (signatureDescription != null)
{
hashAlgorithm = signatureDescription.CreateDigest();
if (hashAlgorithm != null)
{
return(hashAlgorithm);
}
}
hashAlgorithm = algorithmObject as HashAlgorithm;
if (hashAlgorithm != null)
{
return(hashAlgorithm);
}
throw DiagnosticUtility.ExceptionUtility.ThrowHelperWarning(new MessageSecurityException(SR.Format(SR.CustomCryptoAlgorithmIsNotValidAsymmetricSignature, signatureMethod)));
}
switch (signatureMethod)
{
case SecurityAlgorithms.RsaSha1Signature:
case SecurityAlgorithms.DsaSha1Signature:
return(SHA1.Create());
case SecurityAlgorithms.RsaSha256Signature:
return(SHA256.Create());
default:
throw DiagnosticUtility.ExceptionUtility.ThrowHelperWarning(new MessageSecurityException(SR.Format(SR.UnsupportedCryptoAlgorithm, signatureMethod)));
}
}
internal static bool IsSymmetricSupportedAlgorithm(string algorithm, int keySize)
{
bool found = false;
object algorithmObject = null;
try
{
algorithmObject = CryptoAlgorithms.GetAlgorithmFromConfig(algorithm);
}
catch (InvalidOperationException)
{
algorithmObject = null;
// We swallow the exception and continue.
}
if (algorithmObject != null)
{
SymmetricAlgorithm symmetricAlgorithm = algorithmObject as SymmetricAlgorithm;
KeyedHashAlgorithm keyedHashAlgorithm = algorithmObject as KeyedHashAlgorithm;
if (symmetricAlgorithm != null || keyedHashAlgorithm != null)
{
found = true;
}
}
switch (algorithm)
{
case SecurityAlgorithms.DsaSha1Signature:
case SecurityAlgorithms.RsaSha1Signature:
case SecurityAlgorithms.RsaSha256Signature:
case SecurityAlgorithms.RsaOaepKeyWrap:
case SecurityAlgorithms.RsaV15KeyWrap:
return(false);
case SecurityAlgorithms.HmacSha1Signature:
case SecurityAlgorithms.HmacSha256Signature:
case SecurityAlgorithms.Psha1KeyDerivation:
case SecurityAlgorithms.Psha1KeyDerivationDec2005:
return(true);
case SecurityAlgorithms.Aes128Encryption:
case SecurityAlgorithms.Aes128KeyWrap:
return(keySize == 128);
case SecurityAlgorithms.Aes192Encryption:
case SecurityAlgorithms.Aes192KeyWrap:
return(keySize == 192);
case SecurityAlgorithms.Aes256Encryption:
case SecurityAlgorithms.Aes256KeyWrap:
return(keySize == 256);
case SecurityAlgorithms.TripleDesEncryption:
case SecurityAlgorithms.TripleDesKeyWrap:
return(keySize == 128 || keySize == 192);
default:
if (found)
{
return(true);
}
return(false);
}
}
static CryptoAlgorithmType GetAlgorithmType(string algorithm)
{
object algorithmObject = null;
try
{
algorithmObject = CryptoAlgorithms.GetAlgorithmFromConfig(algorithm);
}
catch (InvalidOperationException)
{
algorithmObject = null;
// We swallow the exception and continue.
}
if (algorithmObject != null)
{
SymmetricAlgorithm symmetricAlgorithm = algorithmObject as SymmetricAlgorithm;
KeyedHashAlgorithm keyedHashAlgorithm = algorithmObject as KeyedHashAlgorithm;
if (symmetricAlgorithm != null || keyedHashAlgorithm != null)
{
return(CryptoAlgorithmType.Symmetric);
}
// NOTE: A KeyedHashAlgorithm is symmetric in nature.
AsymmetricAlgorithm asymmetricAlgorithm = algorithmObject as AsymmetricAlgorithm;
SignatureDescription signatureDescription = algorithmObject as SignatureDescription;
if (asymmetricAlgorithm != null || signatureDescription != null)
{
return(CryptoAlgorithmType.Asymmetric);
}
return(CryptoAlgorithmType.Unknown);
}
switch (algorithm)
{
case SecurityAlgorithms.DsaSha1Signature:
case SecurityAlgorithms.RsaSha1Signature:
case SecurityAlgorithms.RsaSha256Signature:
case SecurityAlgorithms.RsaOaepKeyWrap:
case SecurityAlgorithms.RsaV15KeyWrap:
return(CryptoAlgorithmType.Asymmetric);
case SecurityAlgorithms.HmacSha1Signature:
case SecurityAlgorithms.HmacSha256Signature:
case SecurityAlgorithms.Aes128Encryption:
case SecurityAlgorithms.Aes192Encryption:
case SecurityAlgorithms.Aes256Encryption:
case SecurityAlgorithms.TripleDesEncryption:
case SecurityAlgorithms.Aes128KeyWrap:
case SecurityAlgorithms.Aes192KeyWrap:
case SecurityAlgorithms.Aes256KeyWrap:
case SecurityAlgorithms.TripleDesKeyWrap:
case SecurityAlgorithms.Psha1KeyDerivation:
case SecurityAlgorithms.Psha1KeyDerivationDec2005:
return(CryptoAlgorithmType.Symmetric);
default:
return(CryptoAlgorithmType.Unknown);
}
}
