Authorea

Alec Aivazis edited untitled.html over 8 years ago

Commit id: 028bdf5ef1a8914e7a992bc978e19fbf1bd68c12

deletions | additions

In a single page app, all of the decisions about what view/subview to render occurs on the client and does not require a trip back to the server.
This means that the client has to be able to authenticate the currently logged in user and access its data without going back to the server
We have to store information concerning the logged in user in such a way that we can trust it.
- With the rise of the single page app, a new vulnerability server which means it has emerged through the clever use of the javascript console.
  - Previous paradigms did not have this problem because they could authenticate every GET request and prevent the user from going somewhere they shouldn't.
to be stored locally.
href="http://">JWTs are good because they allow for the client to be responsible for keeping track of the permissions of the currently logged in user.
- This removes the need for a session store in most cases which dramatically increases scalability
  - No more potential problem of synchronizing the store among processes with separate memory.
However JWTs require a secret key to be decrypted which means it can't happen on the frontend with the same key that the server uses, say for its csrf protection
- A malicious visiter would be able to download the source code compiled on a few different views and look for similar strings. One of them would be the secret key so its easily brute-forcible.
Because of this it's clear that we need to have unencrypted way of viewing the local authentication data for use by the application logic
Special care needs to be made to prevent someone interacting with the developers console to be able to change the local authentication data in order to gain access to restricted parts of the code by elevating their permissions

permissions

Another reason not to use global variables
This is a different type of network vunerability than the traditional three (xss, csrf, and man in the middle) that arises due to the nature of SPAs
- Previous paradigms did not have this problem because they could authenticate every GET request and prevent the user from going somewhere they shouldn't.

It would be okay to let them modify the data if we had some way of preventing them from doing anything with it afterwards.

We need some way of comparing it to a known valid state corresponding to the logged in user.