c# - 无法将类型为 'Org.BouncyCaSTLe.Asn1.DerSequence' 的对象转换为类型 'Org.BouncyCaSTLe.Asn1.DerInteger'

Question

在我的c#项目中，我放了这段代码:

最初，我从我用充气城堡创建的证书中恢复， key 对，然后我提取私钥，我的目标是，它是一种格式。 pem,

 AsymmetricKeyParameter private_RSA = keyPair2.Private;


            PrivateKeyInfo k_RSA = PrivateKeyInfoFactory.CreatePrivateKeyInfo(private_RSA);
            byte[] serializedKey_priv_RSA = k_RSA.ToAsn1Object().GetDerEncoded();


            //  byte[] clé = Org.BouncyCastle.Utilities.Encoders.Hex.Decode(serializedKey);

            string data_priv_RSA = Convert.ToBase64String(serializedKey_priv_RSA);

using (fluxInfos2 = new StreamWriter("myprivatekey.pem"))
        {
            string ligne = " -----BEGIN RSA PRIVATE KEY-----  ";
            fluxInfos2.WriteLine(ligne);   
            fluxInfos2.WriteLine(data_priv_RSA);
            string lige2 = "-----END RSA PRIVATE KEY----- ";

            fluxInfos2.WriteLine(lige2);


        }
        fluxInfos2.Close();

我的 key 创建完美，即文件包含的内容；

-----BEGIN RSA PRIVATE KEY-----

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

-----END RSA PRIVATE KEY----- 

现在，我必须做相反的事情，即从文件中包含的数据 key ，我必须有一个 RsaPrivateCrtKeyParameters。为此，我编写了这段小代码:

KeyFile string = @ "C: \ Users \ Me \ Documents \ Visual Studio 2010 \ Projects \ PEM \ PEM \ bin \ Debug \ myprivatekey.pem";

RsaPrivateCrtKeyParameters GetPrivateKey privat = (KeyFile);

比如GetPrivateKey，如下:

 public static RsaPrivateCrtKeyParameters GetPrivateKey(String pemFile)
    {
        if (string.IsNullOrEmpty(pemFile)) throw new ArgumentNullException("pemFile");

        string privateKey = File.Exists(pemFile) ? File.ReadAllText(pemFile) : pemFile;

        var reader = new PemReader(new StringReader(privateKey));
        RsaPrivateCrtKeyParameters privkey = null;
        Object obj = reader.ReadObject();
        if (obj is AsymmetricCipherKeyPair)
        {
            privkey = (RsaPrivateCrtKeyParameters)((AsymmetricCipherKeyPair)obj).Private;
        } return privkey;
    } 

问题是我收到异常，在:Object obj = reader.ReadObject();:

 Creating RSA private key problem: System.InvalidCastException:

 Unable to cast object of type 'Org.BouncyCastle.Asn1.DerSequence' to type 'Org.BouncyCastle.Asn1.DerInteger'.
    to Org.BouncyCastle.Asn1.Pkcs.RsaPrivateKeyStructure .. ctor (Asn1Sequence seq)
    to Org.BouncyCastle.OpenSsl.PemReader.ReadKeyPair (String type, String endMarker)

你能帮我吗，谢谢你的帮助

Answer 1

由于您以 PKCS#8 格式写出私钥，因此适当的 PEM header 是“BEGIN PRIVATE KEY”(即没有“RSA”)。 PEM数据已经包含 key 的算法，“BEGIN RSA PRIVATE KEY”具有直接编码的RsaPrivateCrtKeyParameters的含义，这不是你写出来的。

在将 header 更改为“BEGIN PRIVATE KEY”后，我能够解析您的示例文件。 ReadObject 调用然后返回一个 RsaPrivateCrtKeyParameters 对象。