DnsPlugins/Azure.ps1
function Add-DnsTxtAzure { [CmdletBinding()] param( [Parameter(Mandatory,Position=0)] [string]$RecordName, [Parameter(Mandatory,Position=1)] [string]$TxtValue, [Parameter(Mandatory,Position=2)] [string]$AZSubscriptionId, [Parameter(Mandatory,Position=3)] [string]$AZTenantId, [Parameter(Mandatory,Position=4)] [pscredential]$AZAppCred, [Parameter(ValueFromRemainingArguments)] $ExtraParams ) Connect-AZTenant $AZTenantId $AZAppCred Write-Verbose "Attempting to find hosted zone for $RecordName" if (!($zoneID = Get-AZZoneId $RecordName $AZSubscriptionId)) { throw "Unable to find Azure hosted zone for $RecordName" } # check for an existing record $rec = Get-AZTxtRecord $RecordName $zoneID # add (if necessary) the new TXT value to the list if ($rec.etag) { $txtVals = $rec.properties.TXTRecords if ($TxtValue -notin $txtVals.value) { $txtVals += @{value=@($TxtValue)} } } else { $txtVals = @(@{value=@($TxtValue)}) } # build the record update json $recBody = @{properties=@{TTL=10;TXTRecords=$txtVals}} | ConvertTo-Json -Compress -Depth 5 Write-Verbose "Sending updated $($rec.name)" Write-Debug $recBody try { $response = Invoke-RestMethod "https://management.azure.com$($rec.id)?api-version=2018-03-01-preview" ` -Method Put -Body $recBody -Headers $script:AZToken.AuthHeader ` -ContentType 'application/json' @script:UseBasic Write-Debug ($response | ConvertTo-Json -Depth 5) } catch { throw } <# .SYNOPSIS Add a DNS TXT record to an Azure hosted zone. .DESCRIPTION Use an App Registration service principal to add a TXT record to an Azure DNS zone. .PARAMETER RecordName The fully qualified name of the TXT record. .PARAMETER TxtValue The value of the TXT record. .PARAMETER AZSubscriptionId The Subscription ID of the Azure DNS zone. This can be found on the Properties page of the zone. .PARAMETER AZTenantId The Tenant or Directory ID of the Azure AD instance that controls access to your Azure DNS zone. This can be found on the Properties page of your Azure AD instance. .PARAMETER AZAppCred The username and password for an Azure AD App Registration that has permissions to write TXT records on specified zone. The username is the Application ID of the App Registration which can be found on its Properties page. The password is whatever was set at creation time. .PARAMETER ExtraParams This parameter can be ignored and is only used to prevent errors when splatting with more parameters than this function supports. .EXAMPLE $azcred = Get-Credential PS C:\>Add-DnsTxtAzure '_acme-challenge.site1.example.com' 'asdfqwer12345678' -AZSubscriptionId '11111111-1111-1111-1111-111111111111' -AZTenantId '22222222-2222-2222-2222-222222222222' -AZAppCred $azcred Adds a TXT record for the specified site with the specified value. .LINK https://docs.microsoft.com/en-us/powershell/module/azurerm.resources/new-azurermadserviceprincipal .LINK https://docs.microsoft.com/en-us/azure/dns/dns-protect-zones-recordsets #> } function Remove-DnsTxtAzure { [CmdletBinding()] param( [Parameter(Mandatory,Position=0)] [string]$RecordName, [Parameter(Mandatory,Position=1)] [string]$TxtValue, [Parameter(Mandatory,Position=2)] [string]$AZSubscriptionId, [Parameter(Mandatory,Position=3)] [string]$AZTenantId, [Parameter(Mandatory,Position=4)] [pscredential]$AZAppCred, [Parameter(ValueFromRemainingArguments)] $ExtraParams ) Connect-AZTenant $AZTenantId $AZAppCred Write-Verbose "Attempting to find hosted zone for $RecordName" if (!($zoneID = Get-AZZoneId $RecordName $AZSubscriptionId)) { throw "Unable to find Azure hosted zone for $RecordName" } # check for an existing record $rec = Get-AZTxtRecord $RecordName $zoneID # if the record has no etag, it means we faked it because it doesn't exist. # So just return if (!($rec.etag)) { Write-Verbose "Record $($rec.name) already removed." return } # remove the value if it exists $txtVals = $rec.properties.TXTRecords if ($TxtValue -notin $txtVals.value) { Write-Verbose "Record $($rec.name) doesn't contain $TxtValue. Nothing to do." return } $txtVals = @($txtVals | Where-Object { $_.value -ne $TxtValue }) # delete the record if there are no values left if ($txtVals.Count -eq 0) { Write-Verbose "Deleting $($rec.name). No values left." try { Invoke-RestMethod "https://management.azure.com$($rec.id)?api-version=2018-03-01-preview" ` -Method Delete -Headers $script:AZToken.AuthHeader @script:UseBasic | Out-Null return } catch { throw } } # build the record update json $recBody = @{properties=@{TTL=10;TXTRecords=$txtVals}} | ConvertTo-Json -Compress -Depth 5 Write-Verbose "Sending updated $($rec.name)" Write-Debug $recBody try { $response = Invoke-RestMethod "https://management.azure.com$($rec.id)?api-version=2018-03-01-preview" ` -Method Put -Body $recBody -Headers $script:AZToken.AuthHeader ` -ContentType 'application/json' @script:UseBasic Write-Debug ($response | ConvertTo-Json -Depth 5) } catch { throw } <# .SYNOPSIS Remove a DNS TXT record from an Azure hosted zone. .DESCRIPTION Use an App Registration service principal to remove a TXT record from an Azure DNS zone. .PARAMETER RecordName The fully qualified name of the TXT record. .PARAMETER TxtValue The value of the TXT record. .PARAMETER AZSubscriptionId The Subscription ID of the Azure DNS zone. This can be found on the Properties page of the zone. .PARAMETER AZTenantId The Tenant or Directory ID of the Azure AD instance that controls access to your Azure DNS zone. This can be found on the Properties page of your Azure AD instance. .PARAMETER AZAppCred The username and password for an Azure AD App Registration that has permissions to write TXT records on specified zone. The username is the Application ID of the App Registration which can be found on its Properties page. The password is whatever was set at creation time. .PARAMETER ExtraParams This parameter can be ignored and is only used to prevent errors when splatting with more parameters than this function supports. .EXAMPLE $azcred = Get-Credential PS C:\>Remove-DnsTxtAzure '_acme-challenge.site1.example.com' 'asdfqwer12345678' -AZSubscriptionId '11111111-1111-1111-1111-111111111111' -AZTenantId '22222222-2222-2222-2222-222222222222' -AZAppCred $azcred Removes a TXT record for the specified site with the specified value. .LINK https://docs.microsoft.com/en-us/powershell/module/azurerm.resources/new-azurermadserviceprincipal .LINK https://docs.microsoft.com/en-us/azure/dns/dns-protect-zones-recordsets #> } function Save-DnsTxtAzure { [CmdletBinding()] param( [Parameter(ValueFromRemainingArguments)] $ExtraParams ) <# .SYNOPSIS Not required. .DESCRIPTION This provider does not require calling this function to commit changes to DNS records. .PARAMETER ExtraParams This parameter can be ignored and is only used to prevent errors when splatting with more parameters than this function supports. #> } ############################ # Helper Functions ############################ function Connect-AZTenant { [CmdletBinding()] param( [Parameter(Mandatory,Position=0)] [string]$AZTenantId, [Parameter(Mandatory,Position=1)] [pscredential]$AZAppCred ) # just return if we already have a valid Bearer token if ($script:AZToken -and (Get-Date) -lt $script:AZToken.Expires) { return } # build the oAuth2 body $authBody = "grant_type=client_credentials&client_id=$($AZAppCred.Username)&client_secret=$($AZAppCred.GetNetworkCredential().Password)&resource=$([uri]::EscapeDataString('https://management.core.windows.net/'))" # login try { $token = Invoke-RestMethod "https://login.microsoftonline.com/$($AZTenantId)/oauth2/token" ` -Method Post -Body $authBody @script:UseBasic } catch { throw } # add an "Expires" [datetime] parameter converted from expires_on with a 5 min buffer $token | Add-Member -MemberType NoteProperty -Name 'Expires' -Value ([datetime]'1/1/1970').AddSeconds($token.expires_on-300) $script:AZToken = $token | Select-Object ` @{L='Expires';E={([datetime]'1/1/1970').AddSeconds($_.expires_on-300)}}, ` @{L='AuthHeader';E={@{Authorization="Bearer $($_.access_token)"}}} } function Get-AZZoneId { [CmdletBinding()] param( [Parameter(Mandatory,Position=0)] [string]$RecordName, [Parameter(Mandatory,Position=1)] [string]$AZSubscriptionId ) # setup a module variable to cache the record to zone ID mapping # so it's quicker to find later if (!$script:AZRecordZones) { $script:AZRecordZones = @{} } # check for the record in the cache if ($script:AZRecordZones.ContainsKey($RecordName)) { return $script:AZRecordZones.$RecordName } # get the list of available zones # https://docs.microsoft.com/en-us/rest/api/dns/zones/list $url = "https://management.azure.com/subscriptions/$($AZSubscriptionId)/providers/Microsoft.Network/dnszones?api-version=2018-03-01-preview" try { $zones = Invoke-RestMethod $url -Headers $script:AZToken.AuthHeader @script:UseBasic } catch { throw } # Since Azure could be hosting both apex and sub-zones, we need to find the closest/deepest # sub-zone that would hold the record rather than just adding it to the apex. So for something # like _acme-challenge.site1.sub1.sub2.example.com, we'd look for zone matches in the following # order: # - site1.sub1.sub2.example.com # - sub1.sub2.example.com # - sub2.example.com # - example.com Write-Verbose "Found zones: $($zones.value.name -join ', ')" $pieces = $RecordName.Split('.') for ($i=1; $i -lt ($pieces.Count-1); $i++) { $zoneTest = "$( $pieces[$i..($pieces.Count-1)] -join '.' )" Write-Verbose "Checking $zoneTest" if ($zoneTest -in $zones.value.name) { $zoneID = ($zones.value | Where-Object { $_.name -eq $zoneTest }).id $script:AZRecordZones.$RecordName = $zoneID return $zoneID } } return $null } function Get-AZTxtRecord { [CmdletBinding()] param( [Parameter(Mandatory,Position=0)] [string]$RecordName, [Parameter(Mandatory,Position=1)] [string]$ZoneId ) # parse the zone name from the zone id and strip it from $RecordName # to get the relativeRecordSetName $zoneName = $ZoneID.Substring($ZoneID.LastIndexOf('/')+1) $relName = $RecordName.Replace(".$zoneName",'') $recID = "$ZoneID/TXT/$($relName)" # query the specific record we're looking to modify Write-Verbose "Querying $RecordName" try { $rec = Invoke-RestMethod "https://management.azure.com$($recID)?api-version=2018-03-01-preview" ` -Headers $script:AZToken.AuthHeader @script:UseBasic } catch {} if ($rec) { return $rec } else { # build a fake (no etag) empty record to send back $rec = @{id=$recID; name=$relName; properties=@{fqdn="$RecordName."; TXTRecords=@()}} return $rec } } |