Private/Get-EntraIDClientCertificateAccessToken.ps1
function Get-EntraIDClientCertificateAccessToken { [CmdletBinding(DefaultParameterSetName = "default")] Param( [Parameter(Mandatory = $true)] $AccessTokenProfile, [Parameter(Mandatory = $false, ParameterSetName = "resource")] [String] $Resource = $null, [Parameter(Mandatory = $false, ParameterSetName = "scope")] [String] $Scope = $null ) Process { $AssertionJWT = Get-SignedJWT -Payload @{ "aud" = "https://login.microsoftonline.com/$($AccessTokenProfile.TenantId)/oauth2/token" "iss" = $AccessTokenProfile.ClientId "sub" = $AccessTokenProfile.ClientId } -Certificate $AccessTokenProfile.Certificate if ($Scope -or $AccessTokenProfile.scope) { $body = @{ client_id = $AccessTokenProfile.ClientId client_assertion = $AssertionJWT client_assertion_type = "urn:ietf:params:oauth:client-assertion-type:jwt-bearer" scope = [String]::IsNullOrEmpty($Scope) ? $AccessTokenProfile.Scope: $Scope grant_type = "client_credentials" } Write-Verbose "Getting access token (v2/scope) for '$($body.scope)' using Client Certificate for client_id $($AccessTokenProfile.ClientId)" # Get token Invoke-RestMethod -Method Post -Uri "https://login.microsoftonline.com/$($AccessTokenProfile.TenantId)/oauth2/v2.0/token" -Body $body } else { $body = @{ client_id = $AccessTokenProfile.ClientId client_assertion = $AssertionJWT client_assertion_type = "urn:ietf:params:oauth:client-assertion-type:jwt-bearer" resource = [String]::IsNullOrEmpty($Resource) ? $AccessTokenProfile.Resource : $Resource grant_type = "client_credentials" } Write-Verbose "Getting access token (v1/resource) for '$($body.resource)' using Client Certificate for client_id $($AccessTokenProfile.ClientId)" # Get token Invoke-RestMethod -Method Post -Uri "https://login.microsoftonline.com/$($AccessTokenProfile.TenantId)/oauth2/token" -Body $body } } } |