CertEnroll.dll のインターフェイスの実装が、Windows 2008 と Windows 2008 R2 の間でどうにか変更されました。一部の Windows 7 ビルドでも同じだと思います。それを（途中で）機能させるには、クラスをインスタンス化する必要がありますActivator.CreateInstance(Type.GetTypeFromProgID(<TypeName>); これにより、システムは HKLM:\SOFTWARE\Classes\Interface\ 内の参照を検索して、適切なクラスを取得します。
作業例:
(このコードの一部はhttps://stackoverflow.com/a/13806300/5243037から使用されました)
using System;
using System.Collections.Generic;
using System.DirectoryServices.ActiveDirectory;
using System.Linq;
using System.Net;
using System.Net.NetworkInformation;
using System.Net.Sockets;
using System.Security.Cryptography.X509Certificates;
using CERTENROLLLib;
/// <summary>
/// Creates a self-signed certificate in the computer certificate store MY.
/// Issuer and Subject are computername and its domain.
/// </summary>
/// <param name="friendlyName">Friendly-name of the certificate</param>
/// <param name="password">Password which will be used by creation. I think it's obsolete...</param>
/// <returns>Created certificate</returns>
/// <remarks>Base from https://stackoverflow.com/a/13806300/5243037 </remarks>
public static X509Certificate2 CreateSelfSignedCertificate(string friendlyName, string password)
{
// create DN for subject and issuer
var dnHostName = new CX500DistinguishedName();
// DN will be in format CN=machinename, DC=domain, DC=local for machinename.domain.local
dnHostName.Encode(GetMachineDn());
var dnSubjectName = dnHostName;
//var privateKey = new CX509PrivateKey();
var typeName = "X509Enrollment.CX509PrivateKey";
var type = Type.GetTypeFromProgID(typeName);
if (type == null)
{
throw new Exception(typeName + " is not available on your system: 0x80040154 (REGDB_E_CLASSNOTREG)");
}
var privateKey = Activator.CreateInstance(type) as IX509PrivateKey;
if (privateKey == null)
{
throw new Exception("Your certlib does not know an implementation of " + typeName +
" (in HKLM:\\SOFTWARE\\Classes\\Interface\\)!");
}
privateKey.ProviderName = "Microsoft Enhanced RSA and AES Cryptographic Provider";
privateKey.ProviderType = X509ProviderType.XCN_PROV_RSA_AES;
// key-bitness
privateKey.Length = 2048;
privateKey.KeySpec = X509KeySpec.XCN_AT_KEYEXCHANGE;
privateKey.MachineContext = true;
// Don't allow export of private key
privateKey.ExportPolicy = X509PrivateKeyExportFlags.XCN_NCRYPT_ALLOW_EXPORT_NONE;
// use is not limited
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, "SHA512");
// 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 { oid };
var eku = new CX509ExtensionEnhancedKeyUsage();
eku.InitializeEncode(oidlist);
// add all IPs of current machine as dns-names (SAN), so a user connecting to our wcf
// service by IP still claim-trusts this server certificate
var objExtensionAlternativeNames = new CX509ExtensionAlternativeNames();
{
var altNames = new CAlternativeNames();
var dnsHostname = new CAlternativeName();
dnsHostname.InitializeFromString(AlternativeNameType.XCN_CERT_ALT_NAME_DNS_NAME, Environment.MachineName);
altNames.Add(dnsHostname);
foreach (var ipAddress in Dns.GetHostAddresses(Dns.GetHostName()))
{
if ((ipAddress.AddressFamily == AddressFamily.InterNetwork ||
ipAddress.AddressFamily == AddressFamily.InterNetworkV6) && !IPAddress.IsLoopback(ipAddress))
{
var dns = new CAlternativeName();
dns.InitializeFromString(AlternativeNameType.XCN_CERT_ALT_NAME_DNS_NAME, ipAddress.ToString());
altNames.Add(dns);
}
}
objExtensionAlternativeNames.InitializeEncode(altNames);
}
// Create the self signing request
//var cert = new CX509CertificateRequestCertificate();
typeName = "X509Enrollment.CX509CertificateRequestCertificate";
type = Type.GetTypeFromProgID(typeName);
if (type == null)
{
throw new Exception(typeName + " is not available on your system: 0x80040154 (REGDB_E_CLASSNOTREG)");
}
var cert = Activator.CreateInstance(type) as IX509CertificateRequestCertificate;
if (cert == null)
{
throw new Exception("Your certlib does not know an implementation of " + typeName +
" (in HKLM:\\SOFTWARE\\Classes\\Interface\\)!");
}
cert.InitializeFromPrivateKey(X509CertificateEnrollmentContext.ContextMachine, privateKey, "");
cert.Subject = dnSubjectName;
cert.Issuer = dnHostName; // the issuer and the subject are the same
cert.NotBefore = DateTime.Now.AddDays(-1);
// this cert expires immediately. Change to whatever makes sense for you
cert.NotAfter = DateTime.Now.AddYears(1);
cert.X509Extensions.Add((CX509Extension)eku); // add the EKU
cert.X509Extensions.Add((CX509Extension)objExtensionAlternativeNames);
cert.HashAlgorithm = hashobj; // Specify the hashing algorithm
cert.Encode(); // encode the certificate
// Do the final enrollment process
//var enroll = new CX509Enrollment();
typeName = "X509Enrollment.CX509Enrollment";
type = Type.GetTypeFromProgID(typeName);
if (type == null)
{
throw new Exception(typeName + " is not available on your system: 0x80040154 (REGDB_E_CLASSNOTREG)");
}
var enroll = Activator.CreateInstance(type) as IX509Enrollment;
if (enroll == null)
{
throw new Exception("Your certlib does not know an implementation of " + typeName +
" (in HKLM:\\SOFTWARE\\Classes\\Interface\\)!");
}
// Use private key to initialize the certrequest...
enroll.InitializeFromRequest(cert);
enroll.CertificateFriendlyName = friendlyName; // Optional: add a friendly name
var 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, password);
// This will fail on Win2k8, some strange "Parameter is empty" error... Thus we search the
// certificate by serial number with the managed X509Store-class
// // output a base64 encoded PKCS#12 so we can import it back to the .Net security classes
//var base64Encoded = enroll.CreatePFX(password, PFXExportOptions.PFXExportChainNoRoot, EncodingType.XCN_CRYPT_STRING_BASE64);
//return new X509Certificate2(Convert.FromBase64String(base64Encoded), password, X509KeyStorageFlags.MachineKeySet | X509KeyStorageFlags.PersistKeySet);
var certFs = LoadCertFromStore(cert.SerialNumber);
if (!certFs.HasPrivateKey) throw new InvalidOperationException("Created certificate has no private key!");
return certFs;
}
/// <summary>
/// Converts Domain.local into CN=Domain, CN=local
/// </summary>
private static string GetDomainDn()
{
var fqdnDomain = IPGlobalProperties.GetIPGlobalProperties().DomainName;
if (string.IsNullOrWhiteSpace(fqdnDomain)) return null;
var context = new DirectoryContext(DirectoryContextType.Domain, fqdnDomain);
var d = Domain.GetDomain(context);
var de = d.GetDirectoryEntry();
return de.Properties["DistinguishedName"].Value.ToString();
}
/// <summary>
/// Gets machine and domain name in X.500-format: CN=PC,DN=MATESO,DN=local
/// </summary>
private static string GetMachineDn()
{
var machine = "CN=" + Environment.MachineName;
var dom = GetDomainDn();
return machine + (string.IsNullOrWhiteSpace(dom) ? "" : ", " + dom);
}
/// <summary>
/// Load a certificate by serial number from computer.my-store
/// </summary>
/// <param name="serialNumber">Base64-encoded certificate serial number</param>
private static X509Certificate2 LoadCertFromStore(string serialNumber)
{
var store = new X509Store(StoreName.My, StoreLocation.LocalMachine);
store.Open(OpenFlags.OpenExistingOnly | OpenFlags.MaxAllowed);
try
{
// serialnumber from certenroll.dll v6 is a base64 encoded byte array, which is reversed.
// serialnumber from certenroll.dll v10 is a base64 encoded byte array, which is NOT reversed.
var serialBytes = Convert.FromBase64String(serialNumber);
var serial = BitConverter.ToString(serialBytes.ToArray()).Replace("-", "");
var serialReversed = BitConverter.ToString(serialBytes.Reverse().ToArray()).Replace("-", "");
var serverCerts = store.Certificates.Find(X509FindType.FindBySerialNumber, serial, false);
if (serverCerts.Count == 0)
{
serverCerts = store.Certificates.Find(X509FindType.FindBySerialNumber, serialReversed, false);
}
if (serverCerts.Count == 0)
{
throw new KeyNotFoundException("No certificate with serial number <" + serial + "> or reversed serial <" + serialReversed + "> found!");
}
if (serverCerts.Count > 1)
{
throw new Exception("Found multiple certificates with serial <" + serial + "> or reversed serial <" + serialReversed + ">!");
}
return serverCerts[0];
}
finally
{
store.Close();
}
}
備考
では、なぜ「中途半端」と書いたのでしょうか。certenroll.dll V. 6 には問題があり、cert.InitializeFromPrivateKey でビルドが失敗します。certenroll.dll V 6.0 では、2 番目のパラメーターは「CX509PrivateKey」タイプである必要がありますが、Certenroll.dll V 10 を使用する Win10 マシンでは、それは IX509PrivateKey です。
エラー CS1503: 引数 2: 'CERTENROLLLib.IX509PrivateKey' から 'CERTENROLLLib.CX509PrivateKey' に変換できません
そう、上の例の privateKey を Activator.CreateInstance の CX509PrivateKey に「キャスト」するだけです。ここでの問題は、コンパイルされることですが、バニラ Win2k8 ではクラス (CX509...) ではなくインターフェイス (IX509...) が提供されるため、キャストが失敗して null が返されます。
この問題は、certenroll.dll V 10 を搭載したマシン上の別のプロジェクトで certenrollment 関数をコンパイルすることで解決しました。正常にコンパイルされ、Win2k8 でも動作します。ビルドサーバーで certenroll.dll V 6 を使用するとビルドが失敗するため、別のプロジェクトでそれを使用するのは少し面倒です。