Get-PacFile

1.0.4

Get-PacFile.ps1

# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License.

<#PSScriptInfo
 
.VERSION 1.0.4
 
.AUTHOR Microsoft Corporation
 
.GUID 7f692977-e76c-4582-97d5-9989850a2529
 
.COMPANYNAME Microsoft
 
.COPYRIGHT
Copyright (c) Microsoft Corporation. All rights reserved.
Licensed under the MIT License.
 
.TAGS PAC Microsoft Microsoft365 365
 
.LICENSEURI
 
.PROJECTURI http://aka.ms/ipurlws
 
.ICONURI
 
.EXTERNALMODULEDEPENDENCIES
 
.REQUIREDSCRIPTS
 
.EXTERNALSCRIPTDEPENDENCIES
 
.RELEASENOTES
 
#>

<#
 
.SYNOPSIS
 
Create a PAC file for Microsoft 365 prioritized connectivity
 
.DESCRIPTION
 
This script will access updated information to create a PAC file to prioritize Microsoft 365 Urls for
better access to the service. This script will allow you to create different types of files depending
on how traffic needs to be prioritized.
 
.PARAMETER Instance
 
The service instance inside Microsoft 365.
 
.PARAMETER ClientRequestId
 
The client request id to connect to the web service to query up to date Urls.
 
.PARAMETER DirectProxySettings
 
The direct proxy settings for priority traffic.
 
.PARAMETER DefaultProxySettings
 
The default proxy settings for non priority traffic.
 
.PARAMETER Type
 
The type of prioritization to give. Valid values are 1 and 2, which are 2 different modes of operation.
Type 1 will send Optimize traffic to the direct route. Type 2 will send Optimize and Allow traffic to
the direct route.
 
.PARAMETER Lowercase
 
Flag this to include lowercase transformation into the PAC file for the host name matching.
 
.PARAMETER TenantName
 
The tenant name to replace wildcard Urls in the webservice.
 
.PARAMETER ServiceAreas
 
The service areas to filter endpoints by in the webservice.
 
.PARAMETER FilePath
 
The file to print the content to.
 
.EXAMPLE
 
Get-PacFile.ps1 -ClientRequestId b10c5ed1-bad1-445f-b386-b919946339a7 -DefaultProxySettings "PROXY 4.4.4.4:70" -FilePath type1.pac
 
.EXAMPLE
 
Get-PacFile.ps1 -ClientRequestId b10c5ed1-bad1-445f-b386-b919946339a7 -Instance China -Type 2 -DefaultProxySettings "PROXY 4.4.4.4:70" -FilePath type2.pac
 
.EXAMPLE
 
Get-PacFile.ps1 -ClientRequestId b10c5ed1-bad1-445f-b386-b919946339a7 -Instance WorldWide -Lowercase -TenantName tenantName -ServiceAreas Sharepoint,Skype
 
#>

#Requires -Version 2

[CmdletBinding(SupportsShouldProcess=$True)]
Param (
    [Parameter(Mandatory = $false)]
    [ValidateSet('Worldwide', 'Germany', 'China', 'USGovDoD', 'USGovGCCHigh')]
    [String] $Instance = "Worldwide",

    [Parameter(Mandatory = $true)]
    [ValidateNotNullOrEmpty()]
    [guid] $ClientRequestId,

    [Parameter(Mandatory = $false)]
    [ValidateNotNullOrEmpty()]
    [String] $DirectProxySettings = 'DIRECT',

    [Parameter(Mandatory = $false)]
    [ValidateNotNullOrEmpty()]
    [String] $DefaultProxySettings = 'PROXY 10.10.10.10:8080',

    [Parameter(Mandatory = $false)]
    [ValidateRange(1, 2)]
    [int] $Type = 1,

    [Parameter(Mandatory = $false)]
    [switch] $Lowercase = $false,

    [Parameter(Mandatory = $false)]
    [ValidateNotNullOrEmpty()]
    [string] $TenantName,

    [Parameter(Mandatory = $false)]
    [ValidateSet('Exchange', 'Skype', 'SharePoint', 'Common')]
    [string[]] $ServiceAreas,

    [Parameter(Mandatory = $false)]
    [ValidateNotNullOrEmpty()]
    [string] $FilePath
)

##################################################################################################################
### Global constants
##################################################################################################################

$baseServiceUrl = "https://endpoints.office.com/endpoints/$Instance/?ClientRequestId={$ClientRequestId}"
$directProxyVarName = "direct"
$defaultProxyVarName = "proxyServer"
$bl = "`r`n"

##################################################################################################################
### Functions to create PAC files
##################################################################################################################

function Get-PacClauses
{
    param(
        [Parameter(Mandatory = $false)]
        [string[]] $Urls,

        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [String] $ReturnVarName
    )

    if (!$Urls)
    {
        return ""
    }

    $clauses =  (($Urls | ForEach-Object { "shExpMatch(host, `"$_`")" }) -Join "$bl || ")

@"
    if($clauses)
    {
        return $ReturnVarName;
    }
"@
}

function Get-PacString
{
    param(
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [array[]] $MapVarUrls
    )

@"
// This PAC file will provide proxy config to Microsoft 365 services
// using data from the public web service for all endpoints
function FindProxyForURL(url, host)
{
    var $directProxyVarName = "$DirectProxySettings";
    var $defaultProxyVarName = "$DefaultProxySettings";
 
$( if ($Lowercase) { " host = host.toLowerCase();" })
 
$( ($MapVarUrls | ForEach-Object { Get-PACClauses -ReturnVarName $_.Item1 -Urls $_.Item2 }) -Join "$bl$bl" )
 
    return $defaultProxyVarName;
}
"@ -replace "($bl){3,}","$bl$bl" # Collapse more than one blank line in the PAC file so it looks better.
}

##################################################################################################################
### Functions to get and filter endpoints
##################################################################################################################

function Get-Regex
{
    param(
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [string] $Fqdn
    )

    return "^" + $Fqdn.Replace(".", "\.").Replace("*", ".*").Replace("?", ".") + "$"
}

function Match-RegexList
{
    param(
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [string] $ToMatch,

        [Parameter(Mandatory = $false)]
        [string[]] $MatchList
    )

    if (!$MatchList)
    {
        return $false
    }
    foreach ($regex in $MatchList)
    {
        if ($regex -ne $ToMatch -and $ToMatch -match (Get-Regex $regex))
        {
            return $true
        }
    }
    return $false
}

function Get-Endpoints
{
    $url = $baseServiceUrl
    if ($TenantName)
    {
        $url += "&TenantName=$TenantName"
    }
    if ($ServiceAreas)
    {
        $url += "&ServiceAreas=" + ($ServiceAreas -Join ",")
    }
    return Invoke-RestMethod -Uri $url
}

function Get-Urls
{
    param(
        [Parameter(Mandatory = $false)]
        [psobject[]] $Endpoints
    )

    if ($Endpoints)
    {
        return $Endpoints | Where-Object { $_.urls } | ForEach-Object { $_.urls } | Sort-Object -Unique
    }
    return @()
}

function Get-UrlVarTuple
{
    param(
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [string] $VarName,

        [Parameter(Mandatory = $false)]
        [string[]] $Urls
    )
    return New-Object 'Tuple[string,string[]]'($VarName, $Urls)
}

function Get-MapVarUrls
{
    Write-Verbose "Retrieving all endpoints for instance $Instance from web service."
    $Endpoints = Get-Endpoints

    if ($Type -eq 1)
    {
        $directUrls = Get-Urls ($Endpoints | Where-Object { $_.category -eq "Optimize" })
        $nonDirectPriorityUrls = Get-Urls ($Endpoints | Where-Object { $_.category -ne "Optimize" }) | Where-Object { Match-RegexList $_ $directUrls }
        return @(
            Get-UrlVarTuple -VarName $defaultProxyVarName -Urls $nonDirectPriorityUrls
            Get-UrlVarTuple -VarName $directProxyVarName -Urls $directUrls
        )
    }
    elseif ($Type -eq 2)
    {
        $directUrls = Get-Urls ($Endpoints | Where-Object { $_.category -in @("Optimize", "Allow")})
        $nonDirectPriorityUrls = Get-Urls ($Endpoints | Where-Object { $_.category -notin @("Optimize", "Allow") }) | Where-Object { Match-RegexList $_ $directUrls }
        return @(
            Get-UrlVarTuple -VarName $defaultProxyVarName -Urls $nonDirectPriorityUrls
            Get-UrlVarTuple -VarName $directProxyVarName -Urls $directUrls
        )
    }
}

##################################################################################################################
### Main script
##################################################################################################################

$content = Get-PacString (Get-MapVarUrls)

if ($FilePath)
{
    $content | Out-File -FilePath $FilePath -Encoding ascii
}
else
{
    $content
}