DSCResources/DSC_ExchOabVirtualDirectory/DSC_ExchOabVirtualDirectory.psm1

function Get-TargetResource
{
    [Diagnostics.CodeAnalysis.SuppressMessageAttribute("PSDSCUseVerboseMessageInDSCResource", "")]
    [CmdletBinding()]
    [OutputType([System.Collections.Hashtable])]
    param
    (
        [Parameter(Mandatory = $true)]
        [System.String]
        $Identity,

        [Parameter(Mandatory = $true)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential,

        [Parameter()]
        [System.String[]]
        $OABsToDistribute,

        [Parameter()]
        [System.Boolean]
        $AllowServiceRestart = $false,

        [Parameter()]
        [System.Boolean]
        $BasicAuthentication,

        [Parameter()]
        [System.String]
        $DomainController,

        [Parameter()]
        [System.String[]]
        $ExtendedProtectionFlags,

        [Parameter()]
        [System.String[]]
        $ExtendedProtectionSPNList,

        [Parameter()]
        [ValidateSet('None', 'Allow', 'Require')]
        [System.String]
        $ExtendedProtectionTokenChecking,

        [Parameter()]
        [System.String]
        $ExternalUrl,

        [Parameter()]
        [System.String]
        $InternalUrl,

        [Parameter()]
        [System.Boolean]
        $OAuthAuthentication,

        [Parameter()]
        [System.Int32]
        $PollInterval,

        [Parameter()]
        [System.Boolean]
        $RequireSSL,

        [Parameter()]
        [System.Boolean]
        $WindowsAuthentication
    )

    Write-FunctionEntry -Parameters @{
        'Identity' = $Identity
    } -Verbose:$VerbosePreference

    # Establish remote PowerShell session
    Get-RemoteExchangeSession -Credential $Credential -CommandsToLoad 'Get-OabVirtualDirectory', 'Set-OabVirtualDirectory', 'Get-OfflineAddressBook', 'Set-OfflineAddressBook' -Verbose:$VerbosePreference

    Remove-FromPSBoundParametersUsingHashtable -PSBoundParametersIn $PSBoundParameters -ParamsToKeep 'Identity', 'DomainController'

    $vdir = Get-OabVirtualDirectory @PSBoundParameters

    if ($null -ne $vdir)
    {
        Remove-FromPSBoundParametersUsingHashtable -PSBoundParametersIn $PSBoundParameters -ParamsToKeep 'DomainController'

        # Get all OAB's which this VDir distributes for, and add their names to an array
        $oabs = Get-OfflineAddressBook @PSBoundParameters | Where-Object { $_.VirtualDirectories -like "*$($Identity)*" }

        [System.String[]] $oabNames = @()

        if ($null -ne $oabs)
        {
            foreach ($oab in $oabs)
            {
                $oabNames += $oab.Name
            }
        }

        $returnValue = @{
            Identity                        = [System.String] $Identity
            BasicAuthentication             = [System.Boolean] $vdir.BasicAuthentication
            ExtendedProtectionFlags         = [System.String[]] $vdir.ExtendedProtectionFlags
            ExtendedProtectionSPNList       = [System.String[]] $vdir.ExtendedProtectionSPNList
            ExtendedProtectionTokenChecking = [System.String] $vdir.ExtendedProtectionTokenChecking
            ExternalUrl                     = [System.String] $vdir.ExternalUrl.AbsoluteUri
            InternalUrl                     = [System.String] $vdir.InternalUrl.AbsoluteUri
            OABsToDistribute                = [System.String[]] $oabNames
            OAuthAuthentication             = [System.Boolean] $vdir.OAuthAuthentication
            PollInterval                    = [System.Int32] $vdir.PollInterval
            RequireSSL                      = [System.Boolean] $vdir.RequireSSL
            WindowsAuthentication           = [System.Boolean] $vdir.WindowsAuthentication
        }
    }

    $returnValue
}

function Set-TargetResource
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [System.String]
        $Identity,

        [Parameter(Mandatory = $true)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential,

        [Parameter()]
        [System.String[]]
        $OABsToDistribute,

        [Parameter()]
        [System.Boolean]
        $AllowServiceRestart = $false,

        [Parameter()]
        [System.Boolean]
        $BasicAuthentication,

        [Parameter()]
        [System.String]
        $DomainController,

        [Parameter()]
        [System.String[]]
        $ExtendedProtectionFlags,

        [Parameter()]
        [System.String[]]
        $ExtendedProtectionSPNList,

        [Parameter()]
        [ValidateSet('None', 'Allow', 'Require')]
        [System.String]
        $ExtendedProtectionTokenChecking,

        [Parameter()]
        [System.String]
        $ExternalUrl,

        [Parameter()]
        [System.String]
        $InternalUrl,

        [Parameter()]
        [System.Boolean]
        $OAuthAuthentication,

        [Parameter()]
        [System.Int32]
        $PollInterval,

        [Parameter()]
        [System.Boolean]
        $RequireSSL,

        [Parameter()]
        [System.Boolean]
        $WindowsAuthentication
    )

    Write-FunctionEntry -Parameters @{
        'Identity' = $Identity
    } -Verbose:$VerbosePreference

    if ($PSBoundParameters.ContainsKey('OABsToDistribute'))
    {
        # Get existing Vdir props so we can tell if we need to add OAB distribution points
        $vdir = Get-TargetResource @PSBoundParameters

        foreach ($oab in $OABsToDistribute)
        {
            # If we aren't currently distributing an OAB, add it
            if ((Test-ArrayElementsInSecondArray -Array1 $oab -Array2 $vdir.OABsToDistribute -IgnoreCase) -eq $false)
            {
                Add-OabDistributionPoint @PSBoundParameters -TargetOabName "$($oab)"
            }
        }
    }
    else
    {
        # Need to establish a remote PowerShell session since it wasn't done in Get-TargetResource above
        Get-RemoteExchangeSession -Credential $Credential -CommandsToLoad 'Set-OabVirtualDirectory'
    }

    Remove-FromPSBoundParametersUsingHashtable -PSBoundParametersIn $PSBoundParameters -ParamsToRemove 'Credential', 'AllowServiceRestart', 'OABsToDistribute'

    Set-EmptyStringParamsToNull -PSBoundParametersIn $PSBoundParameters

    Set-OabVirtualDirectory @PSBoundParameters

    if ($AllowServiceRestart -eq $true)
    {
        Write-Verbose -Message 'Recycling MSExchangeOABAppPool'

        Restart-ExistingAppPool -Name MSExchangeOABAppPool
    }
    else
    {
        Write-Warning -Message 'The configuration will not take effect until MSExchangeOABAppPool is manually recycled.'
    }
}

function Test-TargetResource
{
    [Diagnostics.CodeAnalysis.SuppressMessageAttribute("PSDSCUseVerboseMessageInDSCResource", "")]
    [CmdletBinding()]
    [OutputType([System.Boolean])]
    param
    (
        [Parameter(Mandatory = $true)]
        [System.String]
        $Identity,

        [Parameter(Mandatory = $true)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential,

        [Parameter()]
        [System.String[]]
        $OABsToDistribute,

        [Parameter()]
        [System.Boolean]
        $AllowServiceRestart = $false,

        [Parameter()]
        [System.Boolean]
        $BasicAuthentication,

        [Parameter()]
        [System.String]
        $DomainController,

        [Parameter()]
        [System.String[]]
        $ExtendedProtectionFlags,

        [Parameter()]
        [System.String[]]
        $ExtendedProtectionSPNList,

        [Parameter()]
        [ValidateSet('None', 'Allow', 'Require')]
        [System.String]
        $ExtendedProtectionTokenChecking,

        [Parameter()]
        [System.String]
        $ExternalUrl,

        [Parameter()]
        [System.String]
        $InternalUrl,

        [Parameter()]
        [System.Boolean]
        $OAuthAuthentication,

        [Parameter()]
        [System.Int32]
        $PollInterval,

        [Parameter()]
        [System.Boolean]
        $RequireSSL,

        [Parameter()]
        [System.Boolean]
        $WindowsAuthentication
    )

    Write-FunctionEntry -Parameters @{
        'Identity' = $Identity
    } -Verbose:$VerbosePreference

    $vdir = Get-TargetResource @PSBoundParameters

    $testResults = $true

    if ($null -eq $vdir)
    {
        Write-Error -Message 'Unable to retrieve OAB Virtual Directory for server'

        $testResults = $false
    }
    else
    {
        if ($PSBoundParameters.ContainsKey('OABsToDistribute') -and (Test-ArrayElementsInSecondArray -Array1 $OABsToDistribute -Array2 $vdir.OABsToDistribute -IgnoreCase) -eq $false)
        {
            Write-InvalidSettingVerbose -SettingName 'OABsToDistribute' -ExpectedValue $OABsToDistribute -ActualValue $vdir.OABsToDistribute -Verbose:$VerbosePreference
        }

        if (!(Test-ExchangeSetting -Name 'BasicAuthentication' -Type 'Boolean' -ExpectedValue $BasicAuthentication -ActualValue $vdir.BasicAuthentication -PSBoundParametersIn $PSBoundParameters -Verbose:$VerbosePreference))
        {
            $testResults = $false
        }

        if (!(Test-ExchangeSetting -Name 'ExtendedProtectionFlags' -Type 'Array' -ExpectedValue $ExtendedProtectionFlags -ActualValue $vdir.ExtendedProtectionFlags -PSBoundParametersIn $PSBoundParameters -Verbose:$VerbosePreference))
        {
            $testResults = $false
        }

        if (!(Test-ExchangeSetting -Name 'ExtendedProtectionSPNList' -Type 'Array' -ExpectedValue $ExtendedProtectionSPNList -ActualValue $vdir.ExtendedProtectionSPNList -PSBoundParametersIn $PSBoundParameters -Verbose:$VerbosePreference))
        {
            $testResults = $false
        }

        if (!(Test-ExchangeSetting -Name 'ExtendedProtectionTokenChecking' -Type 'String' -ExpectedValue $ExtendedProtectionTokenChecking -ActualValue $vdir.ExtendedProtectionTokenChecking -PSBoundParametersIn $PSBoundParameters -Verbose:$VerbosePreference))
        {
            $testResults = $false
        }

        if (!(Test-ExchangeSetting -Name 'ExternalUrl' -Type 'String' -ExpectedValue $ExternalUrl -ActualValue $vdir.ExternalUrl -PSBoundParametersIn $PSBoundParameters -Verbose:$VerbosePreference))
        {
            $testResults = $false
        }

        if (!(Test-ExchangeSetting -Name 'InternalUrl' -Type 'String' -ExpectedValue $InternalUrl -ActualValue $vdir.InternalUrl -PSBoundParametersIn $PSBoundParameters -Verbose:$VerbosePreference))
        {
            $testResults = $false
        }

        if (!(Test-ExchangeSetting -Name 'PollInterval' -Type 'Int' -ExpectedValue $PollInterval -ActualValue $vdir.PollInterval -PSBoundParametersIn $PSBoundParameters -Verbose:$VerbosePreference))
        {
            $testResults = $false
        }

        if (!(Test-ExchangeSetting -Name 'RequireSSL' -Type 'Boolean' -ExpectedValue $RequireSSL -ActualValue $vdir.RequireSSL -PSBoundParametersIn $PSBoundParameters -Verbose:$VerbosePreference))
        {
            $testResults = $false
        }

        if (!(Test-ExchangeSetting -Name 'WindowsAuthentication' -Type 'Boolean' -ExpectedValue $WindowsAuthentication -ActualValue $vdir.WindowsAuthentication -PSBoundParametersIn $PSBoundParameters -Verbose:$VerbosePreference))
        {
            $testResults = $false
        }

        if (!(Test-ExchangeSetting -Name 'OAuthAuthentication' -Type 'Boolean' -ExpectedValue $OAuthAuthentication -ActualValue $vdir.OAuthAuthentication -PSBoundParametersIn $PSBoundParameters -Verbose:$VerbosePreference))
        {
            $testResults = $false
        }
    }

    return $testResults
}

# Adds a specified OAB vdir to the distribution points for an OAB
function Add-OabDistributionPoint
{
    [CmdletBinding()]
    param
    (
        [Parameter(Mandatory = $true)]
        [System.String]
        $Identity,

        [Parameter(Mandatory = $true)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential,

        [Parameter()]
        [System.String[]]
        $OABsToDistribute,

        [Parameter()]
        [System.Boolean]
        $AllowServiceRestart = $false,

        [Parameter()]
        [System.Boolean]
        $BasicAuthentication,

        [Parameter()]
        [System.String]
        $DomainController,

        [Parameter()]
        [System.String[]]
        $ExtendedProtectionFlags,

        [Parameter()]
        [System.String[]]
        $ExtendedProtectionSPNList,

        [Parameter()]
        [ValidateSet('None', 'Allow', 'Require')]
        [System.String]
        $ExtendedProtectionTokenChecking,

        [Parameter()]
        [System.String]
        $ExternalUrl,

        [Parameter()]
        [System.String]
        $InternalUrl,

        [Parameter()]
        [System.Boolean]
        $OAuthAuthentication,

        [Parameter()]
        [System.Int32]
        $PollInterval,

        [Parameter()]
        [System.Boolean]
        $RequireSSL,

        [Parameter()]
        [System.Boolean]
        $WindowsAuthentication,

        [Parameter(Mandatory = $true)] # Extra parameter added just for this function
        [System.String]
        $TargetOabName
    )

    # Keep track of the OAB vdir to add
    $vdirIdentity = $Identity

    # Setup params for Get-OfflineAddressBook
    Add-ToPSBoundParametersFromHashtable -PSBoundParametersIn $PSBoundParameters -ParamsToAdd @{
        'Identity' = $TargetOabName
    }
    Remove-FromPSBoundParametersUsingHashtable -PSBoundParametersIn $PSBoundParameters -ParamsToKeep 'Identity', 'DomainController'

    $oab = Get-OfflineAddressBook @PSBoundParameters

    if ($null -ne $oab)
    {
        # Assemble the list of existing Virtual Directories
        [System.String[]] $allVdirs = @()

        foreach ($vdir in $oab.VirtualDirectories)
        {
            $oabServer = Get-ServerFromOABVdirDN -OabVdirDN $vdir.DistinguishedName

            [System.String] $entry = $oabServer + '\' + $vdir.Name

            $allVdirs += $entry
        }

        # Add desired vdir to existing list
        $allVdirs += $vdirIdentity

        # Set back to the OAB
        Set-OfflineAddressBook @PSBoundParameters -VirtualDirectories $allVdirs
    }
    else
    {
        throw "Unable to find OAB '$($TargetOabName)'"
    }
}

# Gets just the server netbios name from an OAB virtual directory distinguishedName
function Get-ServerFromOABVdirDN
{
    [CmdletBinding()]
    [OutputType([System.String])]
    param
    (
        [Parameter(Mandatory = $true)]
        [System.String]
        $OabVdirDN
    )
    $startString = 'CN=Protocols,CN='
    $endString = ',CN=Servers'

    $startIndex = $OabVdirDN.IndexOf($startString) + $startString.Length
    $length = $OabVdirDN.IndexOf($endString) - $startIndex

    $serverName = $OabVdirDN.Substring($startIndex, $length)

    return $serverName
}

Export-ModuleMember -Function *-TargetResource