1011098 - CSP performs two policy checks for report-only policies (LogViolationDetails double-checks)

Status: RESOLVED DUPLICATE of bug 1199977

(Core :: DOM: Security, defect, P2)

Description

[Sid Stamm [:geekboy or :sstamm]]

Right now when violations are logged via LogViolationDetails, CSP has to run a second check (mPolicies[p]->allows) in case it was a report-only policy that allowed the thing to happen/load but still requires a report.

This is because LogViolationDetails is called once for the set of effective policies, and when it's called it doesn't know which policies were violated and has to check again.

It's crafted this way because:
1.  we don't want the perf hit of assembling violation context information unless necessary since it can be slow
2.  we support mulitple policies (abstracted away as one via nsIContentSecurityPolicy)

We could rewrite violation reporting to use callbacks that do the context assembling, or permits could return an array of policy "violation indicator booleans" that say which policies were violated (and then we could pass that into LogViolationDetails).  Both of these seem kind of cumbersome for the callers.

We should probably wait until the old backend is completely decommissioned (bug 994782) before we do this so there is not more than one implementation to deal with.

Comment 1

[Christoph Kerschbaumer [:ckerschb]]

Inlining the reporting mechanism will eliminate that problem. We are working on that over in Bug 1199977.