/// <summary>
/// Get rsa encrypt max length
/// </summary>
/// <param name="rsa">Rsa instance </param>
/// <param name="padding"><see cref="RSAEncryptionPadding"/></param>
/// <returns></returns>
private static int GetMaxRsaEncryptLength(RSA rsa, RSAEncryptionPadding padding)
{
var offset = 0;
if (padding.Mode == RSAEncryptionPaddingMode.Pkcs1)
{
offset = 11;
}
else
{
if (padding.Equals(RSAEncryptionPadding.OaepSHA1))
{
offset = 42;
}
if (padding.Equals(RSAEncryptionPadding.OaepSHA256))
{
offset = 66;
}
if (padding.Equals(RSAEncryptionPadding.OaepSHA384))
{
offset = 98;
}
if (padding.Equals(RSAEncryptionPadding.OaepSHA512))
{
offset = 130;
}
}
var keySize = rsa.KeySize;
var maxLength = keySize / 8 - offset;
return(maxLength);
}
/// <summary>
/// 最大分块大小
/// </summary>
/// <param name="rsa">RSA实例</param>
/// <param name="padding">填充方式</param>
/// <returns></returns>
private int MaxBlockSize(RSA rsa, RSAEncryptionPadding padding)
{
int offset = 0;
if (padding.Equals(RSAEncryptionPadding.Pkcs1))
{
offset = 11;
}
else if (padding.Equals(RSAEncryptionPadding.OaepSHA1))
{
offset = 42;
}
else if (padding.Equals(RSAEncryptionPadding.OaepSHA256))
{
offset = 66;
}
else if (padding.Equals(RSAEncryptionPadding.OaepSHA384))
{
offset = 98;
}
else if (padding.Equals(RSAEncryptionPadding.OaepSHA512))
{
offset = 130;
}
return(rsa.KeySize / 8 - offset);
}
/// <summary>
/// 按照补位规则计算大小
/// </summary>
/// <param name="rsa"></param>
/// <param name="padding"></param>
/// <returns></returns>
public static int GetMaxBlockSize(RSA rsa, RSAEncryptionPadding padding)
{
var offset = 0;
if (padding.Mode == RSAEncryptionPaddingMode.Pkcs1)
{
offset = 11;
}
else
{
if (padding.Equals(RSAEncryptionPadding.OaepSHA1))
{
offset = 42;
}
if (padding.Equals(RSAEncryptionPadding.OaepSHA256))
{
offset = 66;
}
if (padding.Equals(RSAEncryptionPadding.OaepSHA384))
{
offset = 98;
}
if (padding.Equals(RSAEncryptionPadding.OaepSHA512))
{
offset = 130;
}
}
return(rsa.KeySize / 8 - offset);
}
private Mechanism CreateDecryptMechanism(RSAEncryptionPadding padding)
{
if (padding.Equals(RSAEncryptionPadding.Pkcs1))
{
return(new Mechanism(CKM.CKM_RSA_PKCS));
}
throw new SlovakEidDecryptionException("Unsuported mechanism");
//if (padding.Equals(RSAEncryptionPadding.OaepSHA1))
//{
// return new Mechanism(CKM.CKM_RSA_PKCS_OAEP, new Net.Pkcs11Interop.HighLevelAPI.MechanismParams.CkRsaPkcsOaepParams((ulong)CKM.CKM_SHA_1, (ulong)CKG.CKG_MGF1_SHA1, (ulong)CKZ.CKZ_DATA_SPECIFIED, null));
//}
//if (padding.Equals(RSAEncryptionPadding.OaepSHA256))
//{
// return new Mechanism(CKM.CKM_RSA_PKCS_OAEP, new Net.Pkcs11Interop.HighLevelAPI.MechanismParams.CkRsaPkcsOaepParams((ulong)CKM.CKM_SHA256, (ulong)CKG.CKG_MGF1_SHA256, (ulong)CKZ.CKZ_DATA_SPECIFIED, null));
//}
//if (padding.Equals(RSAEncryptionPadding.OaepSHA384))
//{
// return new Mechanism(CKM.CKM_RSA_PKCS_OAEP, new Net.Pkcs11Interop.HighLevelAPI.MechanismParams.CkRsaPkcsOaepParams((ulong)CKM.CKM_SHA384, (ulong)CKG.CKG_MGF1_SHA384, (ulong)CKZ.CKZ_DATA_SPECIFIED, null));
//}
//if (padding.Equals(RSAEncryptionPadding.OaepSHA512))
//{
// return new Mechanism(CKM.CKM_RSA_PKCS_OAEP, new Net.Pkcs11Interop.HighLevelAPI.MechanismParams.CkRsaPkcsOaepParams((ulong)CKM.CKM_SHA512, (ulong)CKG.CKG_MGF1_SHA512, (ulong)CKZ.CKZ_SALT_SPECIFIED, null));
//}
}