无法使用图谱API在Azure AD中对用户进行身份验证. Graph API为用户的各种与AD相关的操作，在用户，组，目录角色，策略等上签名的方法提供了方法. https://msdn.microsoft.com/zh-CN/library/azure/ad/graph/api/users-operations

It is not possible to authenticate an user in azure AD using graph API. Graph API provides methods to various AD related operations on the users, signed on user, groups, directory roles, policies and so on. https://msdn.microsoft.com/en-us/library/azure/ad/graph/api/users-operations