Add DNS-over-HTTPS (DoH) support (#4856)

* feat: Add DoH templates for DNS providers in configuration

* feat: Implement DoH support for DNS configuration and management

* feat(pester): enhance DNS tests to include DoH server address handling and template application

* fix: address codex feedback

* fix: update existing DoH server entries

* fix: enable DoH auto-upgrade

* fix: handle DNS setup failures

* fix: remove DoH state on DHCP reset

pester/dns.Tests.ps1

@@ -23,6 +23,20 @@ BeforeAll {
         param($Message, $Level, $Component)
     }
 
+    function Add-DnsClientDohServerAddress {
+        param($ServerAddress, $DohTemplate, $AllowFallbackToUdp, $AutoUpgrade, $ErrorAction)
+    }
+    function Set-DnsClientDohServerAddress {
+        param($ServerAddress, $DohTemplate, $AllowFallbackToUdp, $AutoUpgrade, $ErrorAction)
+    }
+    function Get-DnsClientDohServerAddress {
+        param($ServerAddress, $ErrorAction)
+    }
+    function Remove-DnsClientDohServerAddress {
+        param($ServerAddress, $Confirm, $ErrorAction)
+    }
+    function Clear-DnsClientCache { }
+
     . (Join-Path $script:repoRoot "functions\private\Set-WinUtilDNS.ps1")
 }
 
@@ -36,6 +50,7 @@ Describe "Set-WinUtilDNS" {
                         Secondary = "1.0.0.1"
                         Primary6 = "2606:4700:4700::1111"
                         Secondary6 = "2606:4700:4700::1001"
+                        DohTemplate = "https://cloudflare-dns.com/dns-query"
                     }
                 }
             }
@@ -46,6 +61,7 @@ Describe "Set-WinUtilDNS" {
                 Name = "Ethernet"
                 Status = "Up"
                 ifIndex = 7
+                InterfaceGuid = "{1234-5678-90AB-CDEF}"
             }
         }
         Mock Set-DnsClientServerAddress { }
@@ -53,13 +69,25 @@ Describe "Set-WinUtilDNS" {
         Mock Write-WinUtilLog { }
         Mock Write-Warning { }
         Mock Write-Host { }
+
+        Mock Get-Command { return $true } -ParameterFilter { $Name -eq "Add-DnsClientDohServerAddress" }
+        Mock Add-DnsClientDohServerAddress { }
+        Mock Set-DnsClientDohServerAddress { }
+        Mock Get-DnsClientDohServerAddress { return $null }
+        Mock Remove-DnsClientDohServerAddress { }
+        Mock Test-Path { return $false }
+        Mock Get-ChildItem { }
+        Mock New-Item { }
+        Mock New-ItemProperty { }
+        Mock Remove-Item { }
+        Mock Clear-DnsClientCache { }
     }
 
     AfterEach {
         Remove-Variable -Name sync -Scope Script -ErrorAction SilentlyContinue
     }
 
-    It "sets IPv4 and IPv6 DNS server addresses separately" {
+    It "sets IPv4 and IPv6 DNS server addresses separately and applies DoH templates" {
         Set-WinUtilDNS -DNSProvider "Cloudflare"
 
         Should -Invoke -CommandName Set-DnsClientServerAddress -Times 1 -Exactly -ParameterFilter {
@@ -77,9 +105,51 @@ Describe "Set-WinUtilDNS" {
         Should -Invoke -CommandName Set-DnsClientServerAddress -Times 0 -Exactly -ParameterFilter {
             $ServerAddresses.Count -eq 4
         }
+        Should -Invoke -CommandName Add-DnsClientDohServerAddress -Times 4 -Exactly
+        Should -Invoke -CommandName New-ItemProperty -Times 4 -ParameterFilter {
+            $Name -eq "DohFlags" -and $Value -eq 1
+        }
+        Should -Invoke -CommandName Clear-DnsClientCache -Times 1 -Exactly
     }
 
-    It "resets DNS to DHCP for IPv4 and IPv6" {
+    It "updates an existing DoH entry with the selected provider settings" {
+        Mock Get-DnsClientDohServerAddress {
+            if ($ServerAddress -eq "1.1.1.1") {
+                return [pscustomobject]@{ ServerAddress = $ServerAddress }
+            }
+            return $null
+        }
+
+        Set-WinUtilDNS -DNSProvider "Cloudflare"
+
+        Should -Invoke -CommandName Set-DnsClientDohServerAddress -Times 1 -Exactly -ParameterFilter {
+            $ServerAddress -eq "1.1.1.1" -and
+                $DohTemplate -eq "https://cloudflare-dns.com/dns-query" -and
+                $AllowFallbackToUdp -eq $false -and
+                $AutoUpgrade -eq $true
+        }
+        Should -Invoke -CommandName Add-DnsClientDohServerAddress -Times 3 -Exactly
+    }
+
+    It "resets DNS to DHCP and removes the applied DoH configuration" {
+        Mock Test-Path { return $true } -ParameterFilter { $Path -like "*DohInterfaceSettings*" }
+        Mock Get-ChildItem {
+            if ($Path -like "*\Doh6") {
+                return @(
+                    [pscustomobject]@{ PSChildName = "2606:4700:4700::1111" }
+                    [pscustomobject]@{ PSChildName = "2606:4700:4700::1001" }
+                )
+            }
+
+            return @(
+                [pscustomobject]@{ PSChildName = "1.1.1.1" }
+                [pscustomobject]@{ PSChildName = "1.0.0.1" }
+            )
+        }
+        Mock Get-DnsClientDohServerAddress {
+            [pscustomobject]@{ ServerAddress = $ServerAddress }
+        }
+        
         Set-WinUtilDNS -DNSProvider "DHCP"
 
         Should -Invoke -CommandName Set-DnsClientServerAddress -Times 1 -Exactly -ParameterFilter {
@@ -102,6 +172,10 @@ Describe "Set-WinUtilDNS" {
                 $Arguments[4] -eq "name=Ethernet" -and
                 $Arguments[5] -eq "source=dhcp"
         }
+        Should -Invoke -CommandName Remove-Item -Times 1 -Exactly -ParameterFilter {
+            $Path -like "*DohInterfaceSettings*" -and $Recurse -eq $true -and $Force -eq $true
+        }
+        Should -Invoke -CommandName Remove-DnsClientDohServerAddress -Times 4 -Exactly
     }
 
     It "catches DNS setter failures so the tweak runspace can continue" {
@@ -112,7 +186,7 @@ Describe "Set-WinUtilDNS" {
         Should -Invoke -CommandName Write-WinUtilLog -Times 1 -Exactly -ParameterFilter {
             $Level -eq "ERROR" -and
                 $Component -eq "DNS" -and
-                $Message -like "Unable to set DNS provider Cloudflare*"
+                $Message -like "DNS provider Cloudflare was not completed: *"
         }
     }
 }