National secret SM2 and SM4 decryption class written in c#, which can be used for Tencent cloud face authentication

The nuget warehouse reference depends on Ch.Gmsm

SM2 decryption

using Ch.Gmsm;

var sm2data = new SM2("私钥的HEX String", SM2Mode.C1C3C2) //SM2Mode根据需求可选C1C2C3和C1C3C2
              .DecryptByBase64String("待解密的base64编码");

// （可选）根据需求转字符串
var sm2Str = Encoding.UTF8.GetString(sm2data);

SM4 decryption

using Ch.Gmsm;

var sm4data = new SM4(sessionKey)
              .DecryptByBase64String("待解密的base64编码");

// （可选）根据需求转字符串
var sm4Str = Encoding.UTF8.GetString(sm4data);

Tencent face recognition decryption

using Ch.Gmsm;

var sessionKey = new SM2("私钥", SM2Mode.C1C3C2)
              .DecryptByBase64String("DesKey");

var data = new SM4(sessionKey)
              .DecryptByBase64String("UserInfo");

var result = Encoding.UTF8.GetString(data);