nhet_cn_back_main/Common/Util/GM.cs

using Org.BouncyCastle.Asn1.GM;
using Org.BouncyCastle.Asn1.X9;
using Org.BouncyCastle.Asn1;
using Org.BouncyCastle.Crypto.Digests;
using Org.BouncyCastle.Crypto.Engines;
using Org.BouncyCastle.Crypto.Generators;
using Org.BouncyCastle.Crypto.Parameters;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Utilities.Encoders;
using Org.BouncyCastle.Utilities;
using Org.BouncyCastle.X509;
using System.Text;
using Org.BouncyCastle.Math;

namespace Common.Util
{
    public class GM
    {
        private static X9ECParameters x9ECParameters = GMNamedCurves.GetByName("sm2p256v1");
        private static ECDomainParameters ecDomainParameters = new(x9ECParameters.Curve, x9ECParameters.G, x9ECParameters.N);

        /**
         *
         * @param msg
         * @param userId
         * @param privateKey
         * @return r||s，直接拼接byte数组的rs
         */

        public static byte[] SignSm3WithSm2(byte[] msg, byte[] userId, AsymmetricKeyParameter privateKey)
        {
            return RsAsn1ToPlainByteArray(SignSm3WithSm2Asn1Rs(msg, userId, privateKey));
        }

        /**
          * @param msg
          * @param userId
          * @param privateKey
          * @return rs in <b>asn1 format</b>
          */

        public static byte[] SignSm3WithSm2Asn1Rs(byte[] msg, byte[] userId, AsymmetricKeyParameter privateKey)
        {
            ISigner signer = SignerUtilities.GetSigner("SM3withSM2");
            signer.Init(true, new ParametersWithID(privateKey, userId));
            signer.BlockUpdate(msg, 0, msg.Length);
            byte[] sig = signer.GenerateSignature();
            return sig;
        }

        /**
        *
        * @param msg
        * @param userId
        * @param rs r||s，直接拼接byte数组的rs
        * @param publicKey
        * @return
        */

        public static bool VerifySm3WithSm2(byte[] msg, byte[] userId, byte[] rs, AsymmetricKeyParameter publicKey)
        {
            if (rs == null || msg == null || userId == null) return false;
            if (rs.Length != RS_LEN * 2) return false;
            return VerifySm3WithSm2Asn1Rs(msg, userId, RsPlainByteArrayToAsn1(rs), publicKey);
        }

        /**
         *
         * @param msg
         * @param userId
         * @param rs in <b>asn1 format</b>
         * @param publicKey
         * @return
         */

        public static bool VerifySm3WithSm2Asn1Rs(byte[] msg, byte[] userId, byte[] sign, AsymmetricKeyParameter publicKey)
        {
            ISigner signer = SignerUtilities.GetSigner("SM3withSM2");
            signer.Init(false, new ParametersWithID(publicKey, userId));
            signer.BlockUpdate(msg, 0, msg.Length);
            return signer.VerifySignature(sign);
        }

        /**
         * bc加解密使用旧标c1||c2||c3，此方法在加密后调用，将结果转化为c1||c3||c2
         * @param c1c2c3
         * @return
         */

        private static byte[] ChangeC1C2C3ToC1C3C2(byte[] c1c2c3)
        {
            int c1Len = (x9ECParameters.Curve.FieldSize + 7) / 8 * 2 + 1; //sm2p256v1的这个固定65。可看GMNamedCurves、ECCurve代码。
            const int c3Len = 32; //new SM3Digest().getDigestSize();
            byte[] result = new byte[c1c2c3.Length];
            Buffer.BlockCopy(c1c2c3, 0, result, 0, c1Len); //c1
            Buffer.BlockCopy(c1c2c3, c1c2c3.Length - c3Len, result, c1Len, c3Len); //c3
            Buffer.BlockCopy(c1c2c3, c1Len, result, c1Len + c3Len, c1c2c3.Length - c1Len - c3Len); //c2
            return result;
        }

        /**
         * bc加解密使用旧标c1||c3||c2，此方法在解密前调用，将密文转化为c1||c2||c3再去解密
         * @param c1c3c2
         * @return
         */

        private static byte[] ChangeC1C3C2ToC1C2C3(byte[] c1c3c2)
        {
            int c1Len = (x9ECParameters.Curve.FieldSize + 7) / 8 * 2 + 1; //sm2p256v1的这个固定65。可看GMNamedCurves、ECCurve代码。
            const int c3Len = 32; //new SM3Digest().GetDigestSize();
            byte[] result = new byte[c1c3c2.Length];
            Buffer.BlockCopy(c1c3c2, 0, result, 0, c1Len); //c1: 0->65
            Buffer.BlockCopy(c1c3c2, c1Len + c3Len, result, c1Len, c1c3c2.Length - c1Len - c3Len); //c2
            Buffer.BlockCopy(c1c3c2, c1Len, result, c1c3c2.Length - c3Len, c3Len); //c3
            return result;
        }

        /**
         * c1||c3||c2
         * @param data
         * @param key
         * @return
         */

        public static byte[] Sm2Decrypt(byte[] data, AsymmetricKeyParameter key)
        {
            return Sm2DecryptOld(ChangeC1C3C2ToC1C2C3(data), key);
        }

        /**
         * c1||c3||c2
         * @param data
         * @param key
         * @return
         */

        public static byte[] Sm2Encrypt(byte[] data, AsymmetricKeyParameter key)
        {
            return ChangeC1C2C3ToC1C3C2(Sm2EncryptOld(data, key));
        }

        /**
         * c1||c2||c3
         * @param data
         * @param key
         * @return
         */

        public static byte[] Sm2EncryptOld(byte[] data, AsymmetricKeyParameter pubkey)
        {
            SM2Engine sm2Engine = new SM2Engine();
            sm2Engine.Init(true, new ParametersWithRandom(pubkey, new SecureRandom()));
            return sm2Engine.ProcessBlock(data, 0, data.Length);
        }

        /**
         * c1||c2||c3
         * @param data
         * @param key
         * @return
         */

        public static byte[] Sm2DecryptOld(byte[] data, AsymmetricKeyParameter key)
        {
            SM2Engine sm2Engine = new SM2Engine();
            sm2Engine.Init(false, key);
            return sm2Engine.ProcessBlock(data, 0, data.Length);
        }

        /**
         * @param bytes
         * @return
         */

        public static byte[] Sm3(byte[] bytes)
        {
            SM3Digest digest = new();
            digest.BlockUpdate(bytes, 0, bytes.Length);
            byte[] result = DigestUtilities.DoFinal(digest);
            return result;
        }

        private const int RS_LEN = 32;

        private static byte[] BigIntToFixexLengthBytes(BigInteger rOrS)
        {
            // for sm2p256v1, n is 00fffffffeffffffffffffffffffffffff7203df6b21c6052b53bbf40939d54123,
            // r and s are the result of mod n, so they should be less than n and have length<=32
            byte[] rs = rOrS.ToByteArray();
            if (rs.Length == RS_LEN) return rs;
            else if (rs.Length == RS_LEN + 1 && rs[0] == 0) return Arrays.CopyOfRange(rs, 1, RS_LEN + 1);
            else if (rs.Length < RS_LEN)
            {
                byte[] result = new byte[RS_LEN];
                Arrays.Fill(result, (byte)0);
                Buffer.BlockCopy(rs, 0, result, RS_LEN - rs.Length, rs.Length);
                return result;
            }
            else
            {
                throw new ArgumentException("err rs: " + Hex.ToHexString(rs));
            }
        }

        /**
         * BC的SM3withSM2签名得到的结果的rs是asn1格式的，这个方法转化成直接拼接r||s
         * @param rsDer rs in asn1 format
         * @return sign result in plain byte array
         */

        private static byte[] RsAsn1ToPlainByteArray(byte[] rsDer)
        {
            Asn1Sequence seq = Asn1Sequence.GetInstance(rsDer);
            byte[] r = BigIntToFixexLengthBytes(DerInteger.GetInstance(seq[0]).Value);
            byte[] s = BigIntToFixexLengthBytes(DerInteger.GetInstance(seq[1]).Value);
            byte[] result = new byte[RS_LEN * 2];
            Buffer.BlockCopy(r, 0, result, 0, r.Length);
            Buffer.BlockCopy(s, 0, result, RS_LEN, s.Length);
            return result;
        }

        /**
         * BC的SM3withSM2验签需要的rs是asn1格式的，这个方法将直接拼接r||s的字节数组转化成asn1格式
         * @param sign in plain byte array
         * @return rs result in asn1 format
         */

        private static byte[] RsPlainByteArrayToAsn1(byte[] sign)
        {
            if (sign.Length != RS_LEN * 2) throw new ArgumentException("err rs. ");
            BigInteger r = new BigInteger(1, Arrays.CopyOfRange(sign, 0, RS_LEN));
            BigInteger s = new BigInteger(1, Arrays.CopyOfRange(sign, RS_LEN, RS_LEN * 2));
            Asn1EncodableVector v = new Asn1EncodableVector
        {
            new DerInteger(r),
            new DerInteger(s)
        };

            return new DerSequence(v).GetEncoded("DER");
        }

        // 生成公私匙对
        public static AsymmetricCipherKeyPair GenerateKeyPair()
        {
            ECKeyPairGenerator kpGen = new();
            kpGen.Init(new ECKeyGenerationParameters(ecDomainParameters, new SecureRandom()));
            return kpGen.GenerateKeyPair();
        }

        public static ECPrivateKeyParameters GetPrivatekeyFromD(BigInteger d)
        {
            return new ECPrivateKeyParameters(d, ecDomainParameters);
        }

        public static ECPublicKeyParameters GetPublickeyFromXY(BigInteger x, BigInteger y)
        {
            return new ECPublicKeyParameters(x9ECParameters.Curve.CreatePoint(x, y), ecDomainParameters);
        }

        public static AsymmetricKeyParameter GetPublickeyFromX509File(FileInfo file)
        {
            FileStream fileStream = null;
            try
            {
                //file.DirectoryName + "\\" + file.Name
                fileStream = new FileStream(file.FullName, FileMode.Open, FileAccess.Read);
                X509Certificate certificate = new X509CertificateParser().ReadCertificate(fileStream);
                return certificate.GetPublicKey();
            }
            catch (Exception)
            {
                //log.Error(file.Name + "读取失败，异常：" + e);
            }
            finally
            {
                if (fileStream != null)
                    fileStream.Close();
            }
            return null;
        }

        public class Sm2Cert
        {
            public AsymmetricKeyParameter privateKey;
            public AsymmetricKeyParameter publicKey;
            public string certId;
        }

        private static byte[] ToByteArray(int i)
        {
            byte[] byteArray = new byte[4];
            byteArray[0] = (byte)(i >> 24);
            byteArray[1] = (byte)((i & 0xFFFFFF) >> 16);
            byteArray[2] = (byte)((i & 0xFFFF) >> 8);
            byteArray[3] = (byte)(i & 0xFF);
            return byteArray;
        }

        /**
         * 字节数组拼接
         *
         * @param params
         * @return
         */

        private static byte[] Join(params byte[][] byteArrays)
        {
            List<byte> byteSource = new();
            for (int i = 0; i < byteArrays.Length; i++)
            {
                byteSource.AddRange(byteArrays[i]);
            }
            byte[] data = byteSource.ToArray();
            return data;
        }

        /**
         * 密钥派生函数
         *
         * @param Z
         * @param klen
         * 生成klen字节数长度的密钥
         * @return
         */

        private static byte[] KDF(byte[] Z, int klen)
        {
            int ct = 1;
            int end = (int)Math.Ceiling(klen * 1.0 / 32);
            List<byte> byteSource = new();

            for (int i = 1; i < end; i++)
            {
                byteSource.AddRange(Sm3(Join(Z, ToByteArray(ct))));
                ct++;
            }
            byte[] last = Sm3(Join(Z, ToByteArray(ct)));
            if (klen % 32 == 0)
            {
                byteSource.AddRange(last);
            }
            else
                byteSource.AddRange(Arrays.CopyOfRange(last, 0, klen % 32));
            return byteSource.ToArray();
        }

        public static byte[] Sm4DecryptCBC(byte[] keyBytes, byte[] cipher, byte[] iv, string algo)
        {
            if (keyBytes.Length != 16) throw new ArgumentException("err key length");
            if (cipher.Length % 16 != 0 && algo.Contains("NoPadding")) throw new ArgumentException("err data length");

            KeyParameter key = ParameterUtilities.CreateKeyParameter("SM4", keyBytes);
            IBufferedCipher c = CipherUtilities.GetCipher(algo);
            if (iv == null) iv = ZeroIv(algo);
            c.Init(false, new ParametersWithIV(key, iv));
            return c.DoFinal(cipher);
        }

        public static byte[] Sm4EncryptCBC(byte[] keyBytes, byte[] plain, byte[] iv, string algo)
        {
            if (keyBytes.Length != 16) throw new ArgumentException("err key length");
            if (plain.Length % 16 != 0 && algo.Contains("NoPadding")) throw new ArgumentException("err data length");

            KeyParameter key = ParameterUtilities.CreateKeyParameter("SM4", keyBytes);
            IBufferedCipher c = CipherUtilities.GetCipher(algo);
            if (iv == null) iv = ZeroIv(algo);
            c.Init(true, new ParametersWithIV(key, iv));
            return c.DoFinal(plain);
        }

        public static byte[] Sm4EncryptECB(byte[] keyBytes, byte[] plain, string algo)
        {
            if (keyBytes.Length != 16) throw new ArgumentException("err key length");
            //NoPadding 的情况下需要校验数据长度是16的倍数.
            if (plain.Length % 16 != 0 && algo.Contains("NoPadding")) throw new ArgumentException("err data length");

            KeyParameter key = ParameterUtilities.CreateKeyParameter("SM4", keyBytes);
            IBufferedCipher c = CipherUtilities.GetCipher(algo);
            c.Init(true, key);
            return c.DoFinal(plain);
        }

        public static byte[] Sm4DecryptECB(byte[] keyBytes, byte[] cipher, string algo)
        {
            if (keyBytes.Length != 16) throw new ArgumentException("err key length");
            if (cipher.Length % 16 != 0 && algo.Contains("NoPadding")) throw new ArgumentException("err data length");

            KeyParameter key = ParameterUtilities.CreateKeyParameter("SM4", keyBytes);
            IBufferedCipher c = CipherUtilities.GetCipher(algo);
            c.Init(false, key);
            return c.DoFinal(cipher);
        }

        public const string SM4_ECB_NOPADDING = "SM4/ECB/NoPadding";
        public const string SM4_CBC_NOPADDING = "SM4/CBC/NoPadding";
        public const string SM4_ECB_PKCS7PADDING = "SM4/ECB/PKCS7Padding";
        public const string SM4_CBC_PKCS7PADDING = "SM4/CBC/PKCS7Padding";

        /**
         * cfca官网CSP沙箱导出的sm2文件
         * @param pem 二进制原文
         * @param pwd 密码
         * @return
         */

        public static Sm2Cert ReadSm2File(byte[] pem, string pwd)
        {
            Sm2Cert sm2Cert = new();

            Asn1Sequence asn1Sequence = (Asn1Sequence)Asn1Object.FromByteArray(pem);
            //            ASN1Integer asn1Integer = (ASN1Integer) asn1Sequence.getObjectAt(0); //version=1
            Asn1Sequence priSeq = (Asn1Sequence)asn1Sequence[1];//private key
            Asn1Sequence pubSeq = (Asn1Sequence)asn1Sequence[2];//public key and x509 cert

            //            ASN1ObjectIdentifier sm2DataOid = (ASN1ObjectIdentifier) priSeq.getObjectAt(0);
            //            ASN1ObjectIdentifier sm4AlgOid = (ASN1ObjectIdentifier) priSeq.getObjectAt(1);
            Asn1OctetString priKeyAsn1 = (Asn1OctetString)priSeq[2];
            byte[] key = KDF(Encoding.UTF8.GetBytes(pwd), 32);
            byte[] priKeyD = Sm4DecryptCBC(Arrays.CopyOfRange(key, 16, 32),
                    priKeyAsn1.GetOctets(),
                    Arrays.CopyOfRange(key, 0, 16), SM4_CBC_PKCS7PADDING);
            sm2Cert.privateKey = GetPrivatekeyFromD(new BigInteger(1, priKeyD));
            //            log.Info(Hex.toHexString(priKeyD));

            //            ASN1ObjectIdentifier sm2DataOidPub = (ASN1ObjectIdentifier) pubSeq.getObjectAt(0);
            Asn1OctetString pubKeyX509 = (Asn1OctetString)pubSeq[1];
            X509Certificate x509 = new X509CertificateParser().ReadCertificate(pubKeyX509.GetOctets());
            sm2Cert.publicKey = x509.GetPublicKey();
            sm2Cert.certId = x509.SerialNumber.ToString(10); //这里转10进制，有啥其他进制要求的自己改改
            return sm2Cert;
        }

        /**
         *
         * @param cert
         * @return
         */

        public static Sm2Cert ReadSm2X509Cert(byte[] cert)
        {
            Sm2Cert sm2Cert = new();

            X509Certificate x509 = new X509CertificateParser().ReadCertificate(cert);
            sm2Cert.publicKey = x509.GetPublicKey();
            sm2Cert.certId = x509.SerialNumber.ToString(10); //这里转10进制，有啥其他进制要求的自己改改
            return sm2Cert;
        }

        public static byte[] ZeroIv(string algo)
        {
            IBufferedCipher cipher = CipherUtilities.GetCipher(algo);
            int blockSize = cipher.GetBlockSize();
            byte[] iv = new byte[blockSize];
            Arrays.Fill(iv, (byte)0);
            return iv;
        }
    }
}