如何从 .NET 对 X.509 证书的私钥文件设置读取权限

Question

这里是将 pfx 添加到 Cert 存储的代码。

X509Store store = new X509Store( StoreName.My, StoreLocation.LocalMachine );
store.Open( OpenFlags.ReadWrite );
X509Certificate2 cert = new X509Certificate2( "test.pfx", "password" );
store.Add( cert );
store.Close();

但是，我找不到设置 NetworkService 访问私钥的权限的方法。

谁能解释一下？提前致谢。

Answer 1

这个答案来晚了，但我想把它发布给其他在这里搜索的人：

我发现一篇 MSDN 博客文章给出了使用 CryptoKeySecurity here 的解决方案，下面是 C# 解决方案的示例：

var rsa = certificate.PrivateKey as RSACryptoServiceProvider;
if (rsa != null)
{
    // Modifying the CryptoKeySecurity of a new CspParameters and then instantiating
    // a new RSACryptoServiceProvider seems to be the trick to persist the access rule.
    // cf. http://blogs.msdn.com/b/cagatay/archive/2009/02/08/removing-acls-from-csp-key-containers.aspx
    var cspParams = new CspParameters(rsa.CspKeyContainerInfo.ProviderType, rsa.CspKeyContainerInfo.ProviderName, rsa.CspKeyContainerInfo.KeyContainerName)
    {
        Flags = CspProviderFlags.UseExistingKey | CspProviderFlags.UseMachineKeyStore,
        CryptoKeySecurity = rsa.CspKeyContainerInfo.CryptoKeySecurity
    };

    cspParams.CryptoKeySecurity.AddAccessRule(new CryptoKeyAccessRule(sid, CryptoKeyRights.GenericRead, AccessControlType.Allow));

    using (var rsa2 = new RSACryptoServiceProvider(cspParams))
    {
        // Only created to persist the rule change in the CryptoKeySecurity
    }
}

我使用 SecurityIdentifier 来识别帐户，但 NTAccount 也可以。

Answer 2

如果这对其他人有帮助，我在 Powershell 中写下了 Jim Flood 的答案

function Set-PrivateKeyPermissions {
param(
[Parameter(Mandatory=$true)][string]$thumbprint,
[Parameter(Mandatory=$false)][string]$account = "NT AUTHORITY\NETWORK SERVICE"
)
#Open Certificate store and locate certificate based on provided thumbprint
$store = New-Object System.Security.Cryptography.X509Certificates.X509Store("My","LocalMachine")
$store.Open("ReadWrite")
$cert = $store.Certificates | where {$_.Thumbprint -eq $thumbprint}

#Create new CSP object based on existing certificate provider and key name
$csp = New-Object System.Security.Cryptography.CspParameters($cert.PrivateKey.CspKeyContainerInfo.ProviderType, $cert.PrivateKey.CspKeyContainerInfo.ProviderName, $cert.PrivateKey.CspKeyContainerInfo.KeyContainerName)

# Set flags and key security based on existing cert
$csp.Flags = "UseExistingKey","UseMachineKeyStore"
$csp.CryptoKeySecurity = $cert.PrivateKey.CspKeyContainerInfo.CryptoKeySecurity
$csp.KeyNumber = $cert.PrivateKey.CspKeyContainerInfo.KeyNumber

# Create new access rule - could use parameters for permissions, but I only needed GenericRead
$access = New-Object System.Security.AccessControl.CryptoKeyAccessRule($account,"GenericRead","Allow")
# Add access rule to CSP object
$csp.CryptoKeySecurity.AddAccessRule($access)

#Create new CryptoServiceProvider object which updates Key with CSP information created/modified above
$rsa2 = New-Object System.Security.Cryptography.RSACryptoServiceProvider($csp)

#Close certificate store
$store.Close()

}

请注意，帐户参数也可以采用“DOMAIN\USER”的形式（不仅仅是内置名称） - 我在我的环境中对此进行了测试，它会自动将其转换为适当的 SID

Answer 3

要以编程方式进行，您必须做三件事：

1. 获取私钥文件夹的路径。

2. 获取该文件夹中私钥的文件名。

3. 为该文件添加权限。

请参阅this post 了解所有这三个方面的一些示例代码（特别是查看“AddAccessToCertificate”方法）。

Answer 4

您可以使用作为Windows Server 2003 Resource Kit Tools 一部分提供的WinHttpCertCfg.exe tool。

示例：

winhttpcertcfg -g -c LOCAL_MACHINE\My -s test -a NetworkService

或者，您可以使用 WCF SDK 附带的Find Private Key tool 来查找证书私钥文件在磁盘上的位置。然后，您可以简单地使用 ACL 对文件设置正确的权限。

示例：

FindPrivateKey My LocalMachine -n "CN=test"

Answer 5

根据@russ 的回答，

此版本同时支持密钥存储提供程序和传统加密服务提供程序。

function Set-PrivateKeyPermissions {
    param(
        [Parameter(Mandatory=$true)]
        [string]$thumbprint,
        [Parameter(Mandatory=$true)]
        [string]$account
    )

    #Open Certificate store and locate certificate based on provided thumbprint
    $store = New-Object System.Security.Cryptography.X509Certificates.X509Store("My","LocalMachine")
    $store.Open("ReadWrite")
    $cert = $store.Certificates | where {$_.Thumbprint -eq $thumbprint}

    if ($cert.PrivateKey -Eq $null) {
        # Probably using Key Storage Provider rather than crypto service provider
        $rsaCert = [System.Security.Cryptography.X509Certificates.RSACertificateExtensions]::GetRSAPrivateKey($cert)
        if ($rsaCert -Eq $null) {
            throw "Private key on certificate $($cert.Subject) not available"
        }

        $fileName = $rsaCert.key.UniqueName
        $path = "$env:ALLUSERSPROFILE\Microsoft\Crypto\Keys\$fileName"
        $permissions = Get-Acl -Path $path

        $access_rule = New-Object System.Security.AccessControl.FileSystemAccessRule($account, "FullControl", "Allow")
        $permissions.AddAccessRule($access_rule)
        Set-Acl -Path $path -AclObject $permissions
    } else {
        #Create new CSP object based on existing certificate provider and key name
        $csp = New-Object System.Security.Cryptography.CspParameters($cert.PrivateKey.CspKeyContainerInfo.ProviderType, $cert.PrivateKey.CspKeyContainerInfo.ProviderName, $cert.PrivateKey.CspKeyContainerInfo.KeyContainerName)

        # Set flags and key security based on existing cert
        $csp.Flags = "UseExistingKey","UseMachineKeyStore"
        $csp.CryptoKeySecurity = $cert.PrivateKey.CspKeyContainerInfo.CryptoKeySecurity
        $csp.KeyNumber = $cert.PrivateKey.CspKeyContainerInfo.KeyNumber

        # Create new access rule - could use parameters for permissions, but I only needed GenericRead
        $access = New-Object System.Security.AccessControl.CryptoKeyAccessRule($account,"GenericRead","Allow")
        # Add access rule to CSP object
        $csp.CryptoKeySecurity.AddAccessRule($access)

        #Create new CryptoServiceProvider object which updates Key with CSP information created/modified above
        $rsa2 = New-Object System.Security.Cryptography.RSACryptoServiceProvider($csp)
    }

    #Close certificate store
    $store.Close()
}

Answer 6

如果有人感兴趣，这是我为 windows server 2008 找到的解决方案：http://technet.microsoft.com/en-us/library/ee662329.aspx

基本上，我必须向需要使用 MMC 工具访问证书的服务授予权限。像魅力一样工作。

Answer 7

如果Certificate 的PrivateKey 是RSACng 类型，你可以走这条路：

对于本地机器：

 var rsaPrivateKey = certificate.GetRSAPrivateKey();
 var privateKey = rsaPrivateKey as RSACng;
 var keyUniqueName = privateKey.Key.UniqueName;
 var folderPath = Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData);
 var keyPath = Path.Combine(folderPath, "Microsoft", "Crypto", "RSA", "MachineKeys", keyUniqueName);
 var fileInfo = new FileInfo(keyPath);
 var accessControl = fileInfo.GetAccessControl();
 accessControl.AddAccessRule(new FileSystemAccessRule(new NTAccount("<account>"), FileSystemRights.FullControl, AccessControlType.Allow));
 fileInfo.SetAccessControl(accessControl);

如果是用户证书，请使用 Environment.SpecialFolder.ApplicationData 并在文件夹 roaming\microsoft\crypto\rsa 中找到 sid。