At my company we have a central auth server running IdentityServer. There are a number of applications providing some API to client applications. API requests are authenticated with JWT tokens issued by said auth server. It works fine for our purposes.
We have a new requirement that basically needs a secondary verification for some actions.
Scenario goes like this:
- User logs into an app.
- User wants to perform an action that requires elevated access and he is asked to confirm the action.
- User enters a one time password from TOTP/SMS
- Intent is confirmed and API responds to action.
Ihe implementation I have in mind is as follows:
- API gets a request, checks JWT
amrclaim, sees no
otp, returns 401 Unauthorized/403 Forbidden with
WWW-Authenticate: mfa(or something along those lines) and a unique id for action
- App gets 401 response and notices it needs to verify the action with OTP, then redirects to auth server with given id
- Auth server verifies OTP and returns a new but short-lived JWT (with
amr=otp) that only authorizes said action
- App uses this JWT to resend the request to API
- API performs restricted action
- App continues using regular JWT (discards JWT used for OTP)
Now my question is, do you think this is a valid/good approach? Are there better ways of handling this operation?