Middleware to avoid Cross-site request forgery attacks. More info on CSRF at: https://www.owasp.org/index.php/Cross-Site_Request_Forgery_(CSRF)
This middleware is modeled after the double submit cookie pattern: https://www.owasp.org/index.php/Cross-Site_Request_Forgery_(CSRF)_Prevention_Cheat_Sheet#Double_Submit_Cookie
When a user authenticates, embedNew is used to send a random CSRF value as a cookie. (Alternatively, an authenticating service can be wrapped in withNewToken).
By default, for requests that are unsafe (PUT, POST, DELETE, PATCH), services protected by the validated method in the middleware will check that the csrf token is present in both the header headerName and the cookie cookieName. Due to the Same-Origin policy, an attacker will be unable to reproduce this value in a custom header, resulting in a 403 Forbidden response.
By default, requests with safe methods (such as GET, OPTIONS, HEAD) will have a new token embedded in them if there isn't one, or will receive a refreshed token based off of the previous token to mitigate the BREACH vulnerability. If a request contains an invalid token, regardless of whether it is a safe method, this middleware will fail it with 403 Forbidden. In this situation, your user(s) should clear their cookies for your page, to receive a new token.
The default can be overridden by modifying the predicate in validate. It will, by default, check if the method is safe. Thus, you can provide some whitelisting capability for certain kinds of requests.
We'd like to emphasize that you please follow proper design principles in creating endpoints, as to not mutate in what should otherwise be idempotent methods (i.e no dropping your DB in a GET method, or altering user data). Please do not use the CSRF protection from this middleware as a safety net for bad design.
Value parameters
- cookieSettings
-
the CSRF cookie settings
- headerName
-
your CSRF header name
- key
-
the CSRF signing key
Attributes
- Companion
- object
- Source
- CSRF.scala
- Graph
-
- Supertypes
- Self type
-