/// <summary>
/// Decrypt by private key
/// </summary>
/// <param name="dataBytes"></param>
/// <param name="privateKey"></param>
/// <param name="encoding"></param>
/// <param name="mode"></param>
/// <returns></returns>
public static byte[] DecryptByPrivateKeyAsBytes(byte[] dataBytes, string privateKey, Encoding encoding = default, SM2Mode mode = SM2Mode.C1C3C2)
{
if (privateKey is null || privateKey.Length == 0)
{
return(null);
}
if (dataBytes is null || dataBytes.Length == 0)
{
return(null);
}
// ReSharper disable once ExpressionIsAlwaysNull
encoding ??= encoding.SafeValue();
var privateKeyBytes = Hex.Decode(encoding.GetBytes(privateKey));
var(c1, c2, c3) = GetContent(dataBytes, mode, encoding);
var sm2 = SM2Core.Instance;
var userD = new BigInteger(1, privateKeyBytes);
var c = sm2.ecc_curve.DecodePoint(c1);
var cipher = new SM2Core.Cipher();
cipher.Init_dec(userD, c);
cipher.Decrypt(c2);
cipher.Dofinal(c3);
return(c2);
}
/// <summary>
/// Encrypt by public key
/// </summary>
/// <param name="dataBytes"></param>
/// <param name="publicKey"></param>
/// <param name="encoding"></param>
/// <param name="mode"></param>
/// <returns></returns>
public static string EncryptByPublicKey(byte[] dataBytes, string publicKey, Encoding encoding = default, SM2Mode mode = SM2Mode.C1C3C2)
{
if (publicKey is null || publicKey.Length == 0)
{
return(null);
}
if (dataBytes is null || dataBytes.Length == 0)
{
return(null);
}
// ReSharper disable once ExpressionIsAlwaysNull
encoding ??= encoding.SafeValue();
var publicKeyBytes = Hex.Decode(encoding.GetBytes(publicKey));
var source = new byte[dataBytes.Length];
Array.Copy(dataBytes, 0, source, 0, dataBytes.Length);
var cipher = new SM2Core.Cipher();
var sm2 = SM2Core.Instance;
var userKey = sm2.ecc_curve.DecodePoint(publicKeyBytes);
var c1 = cipher.Init_enc(sm2, userKey);
cipher.Encrypt(source);
var c3 = new byte[32];
cipher.Dofinal(c3);
var c1Str = encoding.GetString(Hex.Encode(c1.GetEncoded()));
var c2Str = encoding.GetString(Hex.Encode(source));
var c3Str = encoding.GetString(Hex.Encode(c3));
return(mode == SM2Mode.C1C2C3
? (c1Str + c2Str + c3Str).ToUpper()
: (c1Str + c3Str + c2Str).ToUpper());
}
