使用 CERTENROLLLib 的自签名证书，证书已过期状态

Posted 2023-03-27

【中文标题】使用 CERTENROLLLib 的自签名证书，证书已过期状态

【英文标题】：Self signed certificate using CERTENROLLLib, certificate has expired status

【发布时间】：2019-09-23 19:03:17

【问题描述】：

我正在使用How to create a self-signed certificate using C#? 中的代码在 C# 中生成自签名证书。下面是代码。使用它我可以生成证书并将其添加到 My and Root 存储，但是证书状态显示“证书已过期或尚未生效”，如何解决此问题？

public X509Certificate2 CreateSelfSignedCertificate(string subjectName)
    
        var dn = new CX500DistinguishedName();
        dn.Encode("CN=" + subjectName, X500NameFlags.XCN_CERT_NAME_STR_NONE);

        // create a new private key for the certificate
        CX509PrivateKey privateKey = new CX509PrivateKey();
        privateKey.ProviderName = "Microsoft Strong Cryptographic Provider";
        privateKey.Length = 1024;
        privateKey.KeySpec = X509KeySpec.XCN_AT_KEYEXCHANGE;
        privateKey.KeyUsage = X509PrivateKeyUsageFlags.XCN_NCRYPT_ALLOW_DECRYPT_FLAG | X509PrivateKeyUsageFlags.XCN_NCRYPT_ALLOW_KEY_AGREEMENT_FLAG;
        privateKey.MachineContext = true;
        privateKey.ExportPolicy = X509PrivateKeyExportFlags.XCN_NCRYPT_ALLOW_EXPORT_FLAG;
        privateKey.Create();

        // Use the stronger SHA512 hashing algorithm
        var hashobj = new CObjectId();
        hashobj.InitializeFromAlgorithmName(ObjectIdGroupId.XCN_CRYPT_HASH_ALG_OID_GROUP_ID,
            ObjectIdPublicKeyFlags.XCN_CRYPT_OID_INFO_PUBKEY_ANY,
            AlgorithmFlags.AlgorithmFlagsNone, "SHA1");

        // add extended key usage if you want - look at MSDN for a list of possible OIDs
        var oid = new CObjectId();
        oid.InitializeFromValue("1.3.6.1.5.5.7.3.1"); // SSL server
        var oidlist = new CObjectIds();
        oidlist.Add(oid);
        var eku = new CX509ExtensionEnhancedKeyUsage();
        eku.InitializeEncode(oidlist);

        CObjectId objOID = new CObjectId();
        CAlternativeName objAlternativeName1 = new CAlternativeName();

        CAlternativeNames objAlternativeNames = new CAlternativeNames();
        CX509ExtensionAlternativeNames objExtensionAlternativeNames = new CX509ExtensionAlternativeNames();

        string fqdn = GetFQDN();

        // Create the Issuer Alternative Name as if it were a Subject Alternative Name 
        objAlternativeName1.InitializeFromString(AlternativeNameType.XCN_CERT_ALT_NAME_DNS_NAME, fqdn);
        objAlternativeNames.Add(objAlternativeName1);


        objExtensionAlternativeNames.InitializeEncode(objAlternativeNames);

        // Create the self signing request
        var cert = new CX509CertificateRequestCertificate();
        cert.InitializeFromPrivateKey(X509CertificateEnrollmentContext.ContextMachine, privateKey, "");
        cert.Subject = dn;
        cert.Issuer = dn; // the issuer and the subject are the same
        cert.NotBefore = DateTime.Now;
        // this cert expires immediately. Change to whatever makes sense for you
        //DateTime endtime = new DateTime(DateTime.Now.Year + 20, DateTime.Now.Month, DateTime.Now.Day);
        cert.NotAfter = cert.NotBefore.AddYears(20);
        cert.X509Extensions.Add((CX509Extension)objExtensionAlternativeNames);
        cert.X509Extensions.Add((CX509Extension)eku); // add the EKU
        cert.HashAlgorithm = hashobj; // Specify the hashing algorithm
        cert.Encode(); // encode the certificate

        // Do the final enrollment process
        var enroll = new CX509Enrollment();
        enroll.InitializeFromRequest(cert); // load the certificate
        enroll.CertificateFriendlyName = subjectName; // Optional: add a friendly name
        string csr = enroll.CreateRequest(); // Output the request in base64
                                             // and install it back as the response
        enroll.InstallResponse(InstallResponseRestrictionFlags.AllowUntrustedCertificate,
            csr, EncodingType.XCN_CRYPT_STRING_BASE64, ""); // no password
                                                            // output a base64 encoded PKCS#12 so we can import it back to the .Net security classes
        var base64encoded = enroll.CreatePFX("", // no password, this is for internal consumption
            PFXExportOptions.PFXExportChainWithRoot);

        X509Certificate2 certificate = new X509Certificate2(System.Convert.FromBase64String(base64encoded), "", X509KeyStorageFlags.Exportable);

        X509Store store = new X509Store(StoreName.Root, StoreLocation.LocalMachine);
        store.Open(OpenFlags.ReadWrite);
        store.Add(certificate);
        store.Close();

        // instantiate the target class with the PKCS#12 data (and the empty password)
        return certificate;
    

【参考方案1】：

您必须提供 UTC 日期时间值：

   cert.NotBefore = DateTime.UtcNow;