如何从.NET读取PEM RSA私钥

我有格式的RSA私钥PEM,是否有直接的方式从.NET读取并实例化RSACryptoServiceProvider解密用相应的公钥加密的数据？

1> Simone..：

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我解决了,谢谢.如果有人感兴趣,bouncycastle就是这样做的,只是花了一些时间,因为我缺乏知识和文档.这是代码:

var bytesToDecrypt = Convert.FromBase64String("la0Cz.....D43g=="); // string to decrypt, base64 encoded

AsymmetricCipherKeyPair keyPair; 

using (var reader = File.OpenText(@"c:\myprivatekey.pem")) // file containing RSA PKCS1 private key
    keyPair = (AsymmetricCipherKeyPair) new PemReader(reader).ReadObject(); 

var decryptEngine = new Pkcs1Encoding(new RsaEngine());
decryptEngine.Init(false, keyPair.Private); 

var decrypted = Encoding.UTF8.GetString(decryptEngine.ProcessBlock(bytesToDecrypt, 0, bytesToDecrypt.Length)); 

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@WildJoe:要么是君主的膨胀栖息地,要么是www.bouncycastle.org;)

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什么是bouncycastle？

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@KhurramMajeed RSA不是为加密长消息而设计的,它用于加密长消息通过AES等对称算法加密的秘密.换句话说,如果我想加密很长的消息,我将创建一个秘密,使用秘密AES加密长消息,并使用RSA加密秘密并将两个加密的字符串一起发送给收件人.

2> 小智..：

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关于轻松导入RSA私钥,不使用BouncyCastle等第三方代码,我认为答案是"不,不是单独使用私钥的PEM".

但是,正如Simone所提到的,您可以简单地将私钥(*.key)的PEM和使用该密钥(*.crt)的证书文件组合成*.pfx文件,然后可以轻松导入该文件.

要从命令行生成PFX文件:

openssl pkcs12 -in a.crt -inkey a.key -export -out a.pfx

然后正常使用.NET证书类,例如:

using System.Security.Cryptography.X509Certificates;

X509Certificate2 combinedCertificate = new X509Certificate2(@"C:\path\to\file.pfx");

现在,您可以按照MSDN中的示例通过RSACryptoServiceProvider进行加密和解密:

我遗漏了解密,你需要使用PFX密码和Exportable标志导入.(参见:BouncyCastle RSAPrivateKey到.NET RSAPrivateKey)

X509KeyStorageFlags flags = X509KeyStorageFlags.Exportable;
X509Certificate2 cert = new X509Certificate2("my.pfx", "somepass", flags);

RSACryptoServiceProvider rsa = (RSACryptoServiceProvider)cert.PrivateKey;
RSAParameters rsaParam = rsa.ExportParameters(true); 

3> wprl..：

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您可以查看JavaScience的OpenSSLKey源代码.(OpenSSLKey.cs)

那里的代码完全符合您的要求.

事实上,他们有很多的加密源代码可在这里.

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源代码片段:

//------- Parses binary ans.1 RSA private key; returns RSACryptoServiceProvider  ---
public static RSACryptoServiceProvider DecodeRSAPrivateKey(byte[] privkey)
{
        byte[] MODULUS, E, D, P, Q, DP, DQ, IQ ;

        // ---------  Set up stream to decode the asn.1 encoded RSA private key  ------
        MemoryStream  mem = new MemoryStream(privkey) ;
        BinaryReader binr = new BinaryReader(mem) ;    //wrap Memory Stream with BinaryReader for easy reading
        byte bt = 0;
        ushort twobytes = 0;
        int elems = 0;
        try {
                twobytes = binr.ReadUInt16();
                if (twobytes == 0x8130) //data read as little endian order (actual data order for Sequence is 30 81)
                        binr.ReadByte();        //advance 1 byte
                else if (twobytes == 0x8230)
                        binr.ReadInt16();       //advance 2 bytes
                else
                        return null;

                twobytes = binr.ReadUInt16();
                if (twobytes != 0x0102) //version number
                        return null;
                bt = binr.ReadByte();
                if (bt !=0x00)
                        return null;


                //------  all private key components are Integer sequences ----
                elems = GetIntegerSize(binr);
                MODULUS = binr.ReadBytes(elems);

                elems = GetIntegerSize(binr);
                E = binr.ReadBytes(elems) ;

                elems = GetIntegerSize(binr);
                D = binr.ReadBytes(elems) ;

                elems = GetIntegerSize(binr);
                P = binr.ReadBytes(elems) ;

                elems = GetIntegerSize(binr);
                Q = binr.ReadBytes(elems) ;

                elems = GetIntegerSize(binr);
                DP = binr.ReadBytes(elems) ;

                elems = GetIntegerSize(binr);
                DQ = binr.ReadBytes(elems) ;

                elems = GetIntegerSize(binr);
                IQ = binr.ReadBytes(elems) ;

                Console.WriteLine("showing components ..");
                if (verbose) {
                        showBytes("\nModulus", MODULUS) ;
                        showBytes("\nExponent", E);
                        showBytes("\nD", D);
                        showBytes("\nP", P);
                        showBytes("\nQ", Q);
                        showBytes("\nDP", DP);
                        showBytes("\nDQ", DQ);
                        showBytes("\nIQ", IQ);
                }

                // ------- create RSACryptoServiceProvider instance and initialize with public key -----
                RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
                RSAParameters RSAparams = new RSAParameters();
                RSAparams.Modulus =MODULUS;
                RSAparams.Exponent = E;
                RSAparams.D = D;
                RSAparams.P = P;
                RSAparams.Q = Q;
                RSAparams.DP = DP;
                RSAparams.DQ = DQ;
                RSAparams.InverseQ = IQ;
                RSA.ImportParameters(RSAparams);
                return RSA;
        }
        catch (Exception) {
                return null;
        }
        finally {
                binr.Close();
        }
}

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如果有人想看一看完整的代码示例，这对我也有用，这是一个项目的示例，其中PHP脚本以PEM格式创建密钥并将其发送给C＃，然后使用上述链接将其转换为XML。库：http://csharp-tricks-en.blogspot.de/2015/04/rsa-with-c-and-php.html