处理 AD 用户证书

Question

我是 Powershell 的菜鸟，实际问题是我对如何搜索各种属性有点迷茫，很难找到符合我需要的示例。

话虽如此，我需要搜索 Active Directory 以查找即将过期的用户 S/MIME 证书，这些证书是由特定的证书颁发机构颁发的。

我已经拥有的：

$Mail = user@example.com
$allProfileCerts = Get-ADUser -Server example.com:3268 -Filter {EmailAddress -eq $Mail} -Properties Certificates  | select Certificates

结果是：

       Handle Issuer     Subject                                                                                                             
       ------ ------     -------                                                                                                             
1625625266096 CN=<CA1>   E=test.user@example.com, CN=Test User, OU=Normal, OU=Users, OU=EXAMPLE, ...
1625625265968 CN=<CA2>   E=test.user@example.com, CN=Test User, O=Example Company, ...    
1625625271728 CN=<CA1>   CN=Test User, OU=Normal, OU=Users, OU=EXAMPLE, ...

我认为下一步可以是：

$allProfileCerts.Certificates | foreach {New-Object System.Security.Cryptography.X509Certificates.X509Certificate2 $_}

结果提供了更多详细信息（已编辑以删除 PII）：

EnhancedKeyUsageList     : {Secure Email (1.3.6.1.5.5.7.3.4)}
DnsNameList              : {Test User}
SendAsTrustedIssuer      : False
EnrollmentPolicyEndPoint : Microsoft.CertificateServices.Commands.EnrollmentEndPointProperty
EnrollmentServerEndPoint : Microsoft.CertificateServices.Commands.EnrollmentEndPointProperty
PolicyId                 : 
Archived                 : False
Extensions               : {System.Security.Cryptography.Oid, System.Security.Cryptography.Oid, System.Security.Cryptography.Oid, System.Security.Cryptography.Oid...}
FriendlyName             : 
IssuerName               : System.Security.Cryptography.X509Certificates.X500DistinguishedName
NotAfter                 : 29/05/2021 10:47:00
NotBefore                : 11/12/2018 09:47:00
HasPrivateKey            : False
PrivateKey               : 
PublicKey                : System.Security.Cryptography.X509Certificates.PublicKey
RawData                  : {48, 130, 8, 51...}
SerialNumber             : <snip>
SubjectName              : System.Security.Cryptography.X509Certificates.X500DistinguishedName
SignatureAlgorithm       : System.Security.Cryptography.Oid
Thumbprint               : <snip>
Version                  : 3
Handle                   : 1625625266096
Issuer                   : <ISSUER1>
Subject                  : <subject>

EnhancedKeyUsageList     : {Secure Email (1.3.6.1.5.5.7.3.4)}
DnsNameList              : {Test User}
SendAsTrustedIssuer      : False
EnrollmentPolicyEndPoint : Microsoft.CertificateServices.Commands.EnrollmentEndPointProperty
EnrollmentServerEndPoint : Microsoft.CertificateServices.Commands.EnrollmentEndPointProperty
PolicyId                 : 
Archived                 : False
Extensions               : {System.Security.Cryptography.Oid, System.Security.Cryptography.Oid, System.Security.Cryptography.Oid, System.Security.Cryptography.Oid...}
FriendlyName             : 
IssuerName               : System.Security.Cryptography.X509Certificates.X500DistinguishedName
NotAfter                 : 30/08/2020 14:00:00
NotBefore                : 30/08/2018 02:00:00
HasPrivateKey            : False
PrivateKey               : 
PublicKey                : System.Security.Cryptography.X509Certificates.PublicKey
RawData                  : {48, 130, 5, 127...}
SerialNumber             : <snip>
SubjectName              : System.Security.Cryptography.X509Certificates.X500DistinguishedName
SignatureAlgorithm       : System.Security.Cryptography.Oid
Thumbprint               : <snip>
Version                  : 3
Handle                   : 1625625265968
Issuer                   : <ISSUER2>
Subject                  : <subject>

EnhancedKeyUsageList     : {Encrypting File System (1.3.6.1.4.1.311.10.3.4)}
DnsNameList              : {Test User}
SendAsTrustedIssuer      : False
EnrollmentPolicyEndPoint : Microsoft.CertificateServices.Commands.EnrollmentEndPointProperty
EnrollmentServerEndPoint : Microsoft.CertificateServices.Commands.EnrollmentEndPointProperty
PolicyId                 : 
Archived                 : False
Extensions               : {System.Security.Cryptography.Oid, System.Security.Cryptography.Oid, System.Security.Cryptography.Oid, System.Security.Cryptography.Oid...}
FriendlyName             : 
IssuerName               : System.Security.Cryptography.X509Certificates.X500DistinguishedName
NotAfter                 : 09/04/2020 15:57:37
NotBefore                : 22/10/2017 15:57:37
HasPrivateKey            : False
PrivateKey               : 
PublicKey                : System.Security.Cryptography.X509Certificates.PublicKey
RawData                  : {48, 130, 8, 4...}
SerialNumber             : <snip>
SubjectName              : System.Security.Cryptography.X509Certificates.X500DistinguishedName
SignatureAlgorithm       : System.Security.Cryptography.Oid
Thumbprint               : <snip>
Version                  : 3
Handle                   : 1625625271728
Issuer                   : <ISSUER1>
Subject                  : <subject>

我还认为我可以使用 Where-Object NotAfter... 轻松按日期过滤（如果我在这方面有误，请纠正我 :)），但出于对世界的热爱，我不知道如何过滤EnhancedKeyUsageList : {Secure Email (1.3.6.1.5.5.7.3.4)}。我认为它是一个数组（任何给定的证书中可能有多个 EKU），但我如何按数组元素进行过滤？

奖金问题：如果我有：

$oneCert = $allProfileCerts.Certificates | foreach {New-Object System.Security.Cryptography.X509Certificates.X509Certificate2 $_} | Where-Object SerialNumber -Match "<SN>"

然后如何访问 "NotAfter" 字段？我尝试了 $oneCert."NotAfter"、$oneCert["NotAfter"]、$oneCert | % NotAfter、$oneCert | select -expandproperty "NotAfter" - 都不起作用：/

编辑：有效代码，基于@tomalak 提议：

Get-ADUser -Server $Server -Filter {EmailAddress -eq $Mail} -Property Certificates |
    ForEach-Object {
        # ...we have "user" objects here
        Write-Host $_

        $_.Certificates | 
            foreach {New-Object System.Security.Cryptography.X509Certificates.X509Certificate2 $_} |
            Where-Object {
                $_.EnhancedKeyUsageList.FriendlyName -eq "Secure Email"
            }
    } |
    ForEach-Object {
    # ...we have "certificate" objects here
    Write-Host $_.Issuer
}

Answer 1

我会过滤 ObjectId 值：

$certificates |Where-Object {$_.EnhancedKeyUsageList.ObjectId -like '1.3.6.1.5.5.7.3.2'}

此示例依赖于属性 EnhancedKeyUsageList 中的 OID 枚举，因此它仅适用于 PowerShell 4.0 或更高版本

Answer 2

一般来说，您可以使用 Where-Object 过滤管道，使用 -eq 过滤列表。在这种情况下，类似于：

$adUser.Certificates | Where-Object {
    $_.EnhancedKeyUsageList.oid.Value -eq "1.3.6.1.5.5.7.3.4"
}

将为您提供在其 EKU 列表中具有 "1.3.6.1.5.5.7.3.4" 的所有用户证书。

请注意，当 Powershell（4.0 及更高版本）看到这样的表达式 $object.Property.ChildProperty.SomeData 时，它会获取 all Property 值，对于所有这些值，它都会获取所有 ChildProperty 值，并且对于所有它们，它获取所有SomeData 值。这节省了很多打字。在传统的命令式语言中，您需要嵌套循环，而在 Powershell 中，您根本不需要任何循环。

知道这一点，$_.EnhancedKeyUsageList.oid.Value -eq "1.3.6.1.5.5.7.3.4" 成为可能，因为 -eq 不是您传统的 "equality" 运算符：它获取值列表并将它们过滤掉，即：

1,2,3 -eq 3  # produces 3
1,3,3 -eq 3  # produces 3,3

你可以做到

Get-ADUser -Property Certificates | Where-Object {
    $_.Certificates.EnhancedKeyUsageList.oid.Value -eq "1.3.6.1.5.5.7.3.4"
}

一次性获取所有具有匹配证书的AD用户。

由于您想过滤每个证书的两个属性，我会推荐一些变体

$minValid = (Get-Date).AddMonths(6)

Get-ADUser -Property Certificates -PipelineVariable user | ForEach-Object {
    # ...we have "user" objects here
    Write-Host $_

    $_.Certificates | Where-Object {
        $_.EnhancedKeyUsageList.oid.Value -eq "1.3.6.1.5.5.7.3.4" -and $_.NotAfter -lt $minValid
    }
} | ForEach-Object {
    # ...we have "certificate" objects here
    Write-Host $_
}

处理 AD 用户证书

Processing AD user certificates

powershell

pki

x509certificate