Error 413 after successful login about cloudfront-authorization-at-edge

[ottokruse]

Hi Ben,
Mmm ... strange.

The state is created like this:

      state:
        // Encode the state variable as base64 to avoid a bug in Cognito hosted UI when using multiple identity providers
        // Cognito decodes the URL, causing a malformed link due to the JSON string, and results in an empty 400 response from Cognito.
        urlSafe.stringify(
          Buffer.from(
            JSON.stringify({ nonce: state.nonce, requestedUri })
          ).toString("base64")
        ),

cloudfront-authorization-at-edge/src/lambda-edge/check-auth/index.ts

Line 119 in 7cd699a

state:

Which must mean I think that the requestedUri is super long? (Or we have a bug and a ridiculous long nonce is calculated)

Can you base64 decode the state param and have a look what is in there then?

[BenPortner]

Dear @ottokruse,

thanks for your quick reply. I solved the problem meanwhile by creating a new CloudFront instance. I already deleted the old one, so I cannot check the state param anymore. I am certain that the nonce was fine, though. My guess is that there was a problem with the previous lambda function, which I used to enable basic HTTP authentification (based on this solution). I had removed the corresponding behavior but my guess is that it was still active somehow. Either way, it seems like the problem is not with your code :)

Sorry for the extra work. Hope this is still helpful for other people experiencing similar problems.
Keep up the great work!

Ben