CODEWITHSUNDEEP
azureauthenticationactive-directoryauthorizationazure-functions
Tony Ho
Tony Ho

Reputation: 23

How to check authorization with Azure Functions

I'm using Azure Functions to be the middleman between my Xamarin Forms app and my ComosDB Table. I think I understand how authentication works using Active Directory B2C, but I'm unclear about how authorization checks take place.

My understanding is that I can enable Active Directory B2C to authenticate the user and give them an access token. I can then make an http call to an Azure Function with the token as a parameter. How do I check that the token is correct for that user. Ultimately, I want to protect the data in the Table and only give data relevant to that specific user.

Upvotes: 2

Views: 1938

Answers (1)

juunas
juunas

Reputation: 58733

There are at least 2 approaches to validate tokens in Azure Functions:

The first is that you could do it manually: https://github.com/Azure-Samples/ms-identity-dotnet-webapi-azurefunctions/blob/12640a348852696ac0d01e7adfd937900ef8ea40/Function/BootLoader.cs#L73. This uses Microsoft.IdentityModel.Protocols.OpenIdConnect and System.IdentityModel.Tokens.Jwt to get the configuration from the metadata endpoint and validate the token. The main difference for you would be the openid-configuration URL, which you can get from the view that allows you to run a B2C user flow for testing in Azure portal.

Another approach is to use App Service Authentication: https://cgillum.tech/2016/05/27/app-service-auth-and-azure-ad-b2c/.

Upvotes: 1

Related Questions