How revoke a JWT in Web API C#? - c#

I have a web API in C # (no core) to which I integrated JWT, so there is no problem, now, I would like to know how to revoke a JWT that currently exists, delete it before it expires.
That is, my JWT lasts a total of 20 minutes, but when I close the session, in my APPS I delete that JWT so that they can no longer use it, but in the API, that JWT remains active until it expires for time, how can I delete or expire that JWT in my API?

So basically you want to make inactive just one Jwt token issued by your Api while rest of them are still active. You can't do this straightaway.
Most feasible solution would be to,
Have a smaller lifespan for the Jwt tokens. Then you have to implement refresh token logic as well. If already in place you are good. Now if you want to inactive the token for specific user you can remove the refresh token from the back end. Then the next time user try to refresh, it fails. But still he can access the system until the issued Jwt expires. So make it's lifespan small such as 1 or 2 minutes so that the impact is low.
Cheers,

Related

Validate JWT token in .Net

I have an application to save Azure Active Directory users to SQL Server. For this I am using MSAL authentication to get the users.
But sometimes my access token will get expired and I will get 401 unauthorized error from Graph. So I need to add the logic of validating the expiry in my code itself. I searched a lot but couldn't find a good solution.
Could anybody help me how to achieve this?
The default lifetime of an access token is variable. When issued, an access token's default lifetime is assigned a random value ranging between 60-90 minutes (75 minutes on average). I suggest you save the Refresh token instead and then obtain the access token any time you want to query the users resource.
The reason for that is that the Refresh tokens have a longer lifetime than access tokens. The default lifetime for the tokens is 90 days and they replace themselves with a fresh token upon every use. As such, whenever a refresh token is used to acquire a new access token, a new refresh token is also issued. The Microsoft identity platform doesn't revoke old refresh tokens when used to fetch new access tokens. Securely delete the old refresh token after acquiring a new one. Refresh tokens need to be stored safely like access tokens or application credentials.
More about Refresh token in Microsoft identity platform can be found here - https://learn.microsoft.com/en-us/azure/active-directory/develop/refresh-tokens

What is purpose of "Refresh Token Rolling"?

I now setting up my auth server with Openiddict framework and in configuration section I see this:
What is purpose of refresh token rolling? All I understood until now is that because of this "rolling" my 14 days token expiration time is set up to 30 seconds and I have no idea why I need two versions of expiration time for refresh token.
https://datatracker.ietf.org/doc/html/draft-ietf-oauth-security-topics-16#section-4.13.2
Refresh token rotation: the authorization server issues a new
refresh token with every access token refresh response. The
previous refresh token is invalidated but information about the
relationship is retained by the authorization server. If a
refresh token is compromised and subsequently used by both the
attacker and the legitimate client, one of them will present an
invalidated refresh token, which will inform the authorization
server of the breach. The authorization server cannot determine
which party submitted the invalid refresh token, but it will
revoke the active refresh token. This stops the attack at the
cost of forcing the legitimate client to obtain a fresh
authorization grant."

How to get OAuth2 authentication without user intervention

I am making an API call that requires OAuth2. I initially make the call and authorize it with a login via the web. I'm then taking the supplied Refresh Token and using it to make subsequent calls in my application.
The issue is that in the subsequent calls the Refresh Token is used up and I get a new one. I save this new one in the database and then use that saved one on the next call. This works great for about xx number of calls and then for some reason the Refresh Token goes bad and I have to go and manually grab one through the web login again.
I have no way to tell, that I know of, when the token goes bad or why.
Is there a way to just send the login info or the OAuth2 info or something that'll get me a new valid Refresh Token without me having to "authorize" my own app?
The API that I am using is Constant Contact.
The OAuth standards are based on 2 forms of expiry:
ACCESS TOKENS
These are short lived API credentials and a common lifetime is 60 minutes. When they expire the API client receives an HTTP response with a 401 status code. The client can then try to silently renew the access token.
REFRESH TOKENS
These are long lived credentials that represent a user session, and a common lifetime is 8 or 12 hours. During this time the access token can be renewed silently. Eventually however, the refresh token itself expires and the silent renewal request results in an error with an invalid_grant error code.
USER RE-AUTHENTICATION
There are very good reasons for making users re-authenticate and I would avoid trying to bypass this. Tokens that last for a very long time are not recommended. Usability can be pretty good with only an occasional re-authenticate operation, along with features such as password autofill.
FURTHER DETAILS
See steps 26 and 29 of my Message Workflow
Code that handles 401 checks
Code that handles ErrorCodes.invalidGrant

Xamarin.iOS / Web API JWT refresh token if it expires

I have a Web API that provides the user all the data that needs to be shown on my mobile application.
OWIN JWT Authentication is implemented and it's working properly. There's an endpoint /oauth2/token which provides the user a token and all the endpoints has [Authorize] attribute filter to validate it.
The token expiration is set to 5 minutes.
Login session is maintained through a separated SESSION-ID which is stored into the Keychain and also server-side to check the active session. Everytime a user login inside the application a new token is generated and the user can access API methods to get data.
The question
What if the user leave the application opened for more than 5 minutes (Token expiration time)? The token will not be available since it has expired, how can I refresh it? And when should I refresh it?
I read about refresh tokens but not sure how to handle them (Is thist the right choice?), since the [Authorize] attribute will just reject my call if the token has expired, without providing an expiration message, I can't understand when it is an expired token or an invalid one.
What if the user leave the application opened for more than 5 minutes
(Token expiration time)? The token will not be available since it has
expired, how can I refresh it?
If I understand right, you set The token expiration to 5 minutes, that means if the user leave the application opened for more than 5 minutes, the token is no longer valid. Actually the user has to relogin to get the new token.
So back to your question, at the moment the token is expired, my advice is you can present the loginPage and tell user that he has to login again to use the app.
I don't know if there is another way to get a new token, if there is one, use may not have to relogin,.
Also, I found a thread that may help: webapi-2-0-how-to-implement-refresh-jwt-token-when-access-token-expired

Is it necessary to persist refresh token in database

I am using resource owner password flow and i got successfully access token and refresh token and i did not persist any token in database and everything works fine locally.
But when i deploy identity server in production refresh token is not working as expected.
i have set access token expired time 20 minutes and refresh token expiry time 7 days.
if i refresh access token within 20 minutes or before expiry of access token then refresh token refresh access token and work as expected but after expiry of access token refresh token does not refresh access token and throw invalid_grant error.
As i did not save refresh token in database and i searched on google but answers are confusion.
So can anyone tell me :
Do i need to store refresh token while it is working fine locally without storing ? if yes any implementation reference i am using mysql as database.
or something else i need to look.
Thank you.
Your response is valuable for me.
When running IdentityServer4 locally and "out of the box", things like refresh tokens aren't persisted and that's usually fine in the early stages of development.
When planning to deploy your Identity Provider to a server however, you'll need an operational store anyway (for storing grants, user consent, etc.).
This operational store can also store refresh tokens and reference tokens (read up on it in the IdentityServer4 docs).
Setting up token storage on the IdP is a good idea. Storing tokens opens the door to clean token revocation. A cleanly implemented sign-out in a client application would call the token revocation endpoint on your IdP. That's because when a user logs out, neither the access token nor the refresh token is needed any longer.
You can also revoke tokens from your end, making subsequent API calls fail for that access token and there are some compelling use cases for that as well.

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