Forum Discussion

Ian_Morrish's avatar
Ian_Morrish
Brass Contributor
Mar 09, 2022

Azure B2C oidc authentication with SPSE failed

My AuthorizationEndpoint is defined in SP as

 
But when SP redirects, it drops the p=b2c_1a_signup_signin" and just has ?client_id=xxx...
Resulting in 404
 
I'm using custom Exp Framework in B2C so I can specify known x5c certificate for which the .cer is added to SP
 
Has anyone else got this to work?
  • Ian_Morrish's avatar
    Ian_Morrish
    Brass Contributor
    Mar 10, 2022
    Think I found my problem, should be using OpenID connect format, not OAuth2. Very subtle difference where the flow name goes.
    GET https://{tenant}.b2clogin.com/{tenant}.onmicrosoft.com/{policy}/oauth2/v2.0/authorize?
    • Steve Zhang's avatar
      Steve Zhang
      Icon for Microsoft rankMicrosoft
      Mar 11, 2022
      Thank you Ian for trying on OIDC in SPSE. Good to know that you sorted out the problem.
      Please let us know if you have further problem or suggestion regarding SharePoint Server authentication.
      • Ian_Morrish's avatar
        Ian_Morrish
        Brass Contributor
        Mar 26, 2022
        Hmmm, still didn't work because SharePoint adds ?Source=/ to the redirect_uri which B2C apps don’t allow (Azure AD does allow and sample guide for configuring OIDC in Azure AD shows modifying the manafest to allow /* which is blocked in B2C).
        URL Rewrite to the rescue. Handling the Password Rest flow from B2C is a little more tricky.

Resources