如何在不使用过时的BouncyCastle 1.7.0代码的情况下生成自签名证书

Question

我有以下代码，它生成了一个很好的自签名证书，效果很好，但我想更新到最新的BouncyCastle（1.8.1.0），我收到了关于过时用法的警告：

var persistedCertificateFilename = "ClientCertificate.pfx";
if (!string.IsNullOrWhiteSpace(ConfigurationManager.AppSettings["PersistedCertificateFilename"])) { persistedCertificateFilename = ConfigurationManager.AppSettings["PersistedCertificateFilename"].Trim(); }
if (persistCertificateToDisk)
{
    if (File.Exists(persistedCertificateFilename))
    {
        var certBytes = File.ReadAllBytes(persistedCertificateFilename);
                this.clientCertificate = new X509Certificate2(certBytes, (string) null, X509KeyStorageFlags.MachineKeySet | X509KeyStorageFlags.Exportable | X509KeyStorageFlags.PersistKeySet);
    }
}
if (this.clientCertificate == null)
{
    // Initialize the new secure keys
    KeyGenerator keyGenerator = KeyGenerator.Create();
    KeyPair keyPair = keyGenerator.GenerateKeyPair();
    this.privateKey = keyPair.ToEncryptedPrivateKeyString(privateKeySecret);
    this.publicKey = keyPair.ToPublicKeyString();
    // Client certificate permissions
    var certificatePermissions = new ArrayList()
    {
         KeyPurposeID.IdKPCodeSigning,
         KeyPurposeID.IdKPServerAuth,
         KeyPurposeID.IdKPTimeStamping,
         KeyPurposeID.IdKPOcspSigning,
         KeyPurposeID.IdKPClientAuth
    };
    // Initialize the certificate generation
    var certificateGenerator = new X509V3CertificateGenerator();
    BigInteger serialNo = BigInteger.ProbablePrime(128, new Random());
    certificateGenerator.SetSerialNumber(serialNo);
    certificateGenerator.SetSubjectDN(GetLicenseeDN());
    certificateGenerator.SetIssuerDN(GetLicencerDN());
    certificateGenerator.SetNotAfter(DateTime.Now.AddYears(100));
    certificateGenerator.SetNotBefore(DateTime.Now.Subtract(new TimeSpan(7, 0, 0, 0)));
    //ISignatureFactory signatureFactory = new Asn1SignatureFactory("SHA512WITHRSA", keyPair.PrivateKey); // ??
    certificateGenerator.SetSignatureAlgorithm("SHA512withRSA");
    certificateGenerator.AddExtension(X509Extensions.ExtendedKeyUsage, false, new ExtendedKeyUsage(certificatePermissions));
    var subjectKeyIdentifier = new SubjectKeyIdentifier(SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo(keyPair.PublicKey));
    certificateGenerator.AddExtension(X509Extensions.SubjectKeyIdentifier.Id, false, subjectKeyIdentifier);
    certificateGenerator.SetPublicKey(keyPair.PublicKey);
    var result = certificateGenerator.Generate(keyPair.PrivateKey);
    var secure = new SecureString();
    foreach (char c in privateKeySecret)
    {
        secure.AppendChar(c);
    }
    X509KeyStorageFlags flags = X509KeyStorageFlags.MachineKeySet;
    if (persistCertificateToDisk) { flags |= X509KeyStorageFlags.Exportable; flags |= X509KeyStorageFlags.PersistKeySet; }
    this.clientCertificate = new X509Certificate2(Org.BouncyCastle.Security.DotNetUtilities.ToX509Certificate(result).Export(X509ContentType.Cert), secure, flags);
    // This section allows us to use this certificate on Azure (no file access required)
    CspParameters cspParams;
    const int PROVIDER_RSA_FULL = 1;
    cspParams = new CspParameters(PROVIDER_RSA_FULL);
    cspParams.KeyContainerName = new Guid().ToString();
    cspParams.Flags = CspProviderFlags.UseMachineKeyStore;
    cspParams.ProviderName = "Microsoft Strong Cryptographic Provider";
    var rule = new CryptoKeyAccessRule("everyone", CryptoKeyRights.FullControl, AccessControlType.Allow);
    cspParams.CryptoKeySecurity = new CryptoKeySecurity();
    cspParams.CryptoKeySecurity.SetAccessRule(rule);
    // Set the private key
    var tempRcsp = (RSACryptoServiceProvider) Org.BouncyCastle.Security.DotNetUtilities.ToRSA((RsaPrivateCrtKeyParameters) keyPair.PrivateKey);
    var rcsp = new RSACryptoServiceProvider(cspParams);
    rcsp.ImportCspBlob(tempRcsp.ExportCspBlob(true));
    this.clientCertificate.PrivateKey = rcsp;
    if (persistCertificateToDisk)
    {
        if (!File.Exists(persistedCertificateFilename))
        {
            File.WriteAllBytes(persistedCertificateFilename, this.clientCertificate.Export(X509ContentType.Pkcs12, (string) null));
        }
    }
}

具体来说，警告是：

"X509V3CertificateGenerator.SSetSignatureAlgorithm（string）"为过时："如果Generate与ISignatureFactory一起使用，则不需要"

和

"X509V3CertificateGenerator.Genere（AsymmetricKeyParameter）"为过时："使用ISignatureFactory生成"

所以，我的问题是：

1. 我需要担心这些警告吗
2. 如果是，哪些线条会发生变化
3. 如果我确实更新了这段代码，是否有性能优势

注意：如果有人好奇的话，我将其保存到磁盘的原因是，每次实例化客户端时，这段代码都会创建一个证书，由于最小密钥大小为2048，性能为1.7.0，这一点尤其苛刻。

Answer 1

我也为此挣扎了一段时间。我终于有了解决办法。让我们看看其中一个错误：

'X509V3CertificateGenerator.Generate(AsymmetricKeyParameter)' is obsolete: 'Use Generate with an ISignatureFactory'

你基本上是在使用（我也在做同样的事情）Generate方法，如下所示：

var certificate = certificateGenerator.Generate(issuerCertificate.PrivateKey, random);

其中certificateGenerator是类CertificateContainer的实例错误表明：'Use Generate with an ISignatureFactory'
因此，让我们首先为ISignatureFactory创建一个实例。

ISignatureFactory signatureFactory = new Asn1SignatureFactory("SHA512WITHRSA", issuerKeyPair.Private, random);

为了在这之前正确工作，你还应该声明以下内容：

var randomGenerator = new CryptoApiRandomGenerator();
var random = new SecureRandom(randomGenerator);
AsymmetricCipherKeyPair subjectKeyPair = default(AsymmetricCipherKeyPair);
var keyGenerationParameters = new KeyGenerationParameters(random, keyStrength);
keyPairGenerator.Init(keyGenerationParameters);
subjectKeyPair = keyPairGenerator.GenerateKeyPair();
AsymmetricCipherKeyPair issuerKeyPair = subjectKeyPair;

现在，在这些更改之后，将方法Generate从：更改为

var certificate = certificateGenerator.Generate(issuerCertificate.PrivateKey, random);

至：

var certificate = certificateGenerator.Generate(signatureFactory);

我希望它能有所帮助。