[Zope] Problems with removing Verbose Security and using Apelib

[Chris Kratz]

On Tuesday 15 February 2005 09:49 am, Chris Kratz wrote:
> On Saturday 12 February 2005 02:18 pm, Dieter Maurer wrote:
> > Chris Kratz wrote at 2005-2-11 12:39 -0500:
> > > ...
> > >I removed the Verbose Security from the products directory and from the
> > >Products list in the control panel and tried the app again.
> > >
> > >Unfortunately, this causes the app to break.
> > > ...
> > >The last piece of the puzzle is that returning the VerboseSecurity
> > > product allows the application to start working again, proxy roles and
> > > all.  Any ideas as to why this might be?  Is there a chance that the
> > > monkey patching Verbose Security does is not reversible?
> >
> > ...
> > By the way, I had the impression that VerboseSecurity becomes
> > ineffective as soon as you switch to "security-policy" "C"
> > rather than "python" (but I may well be wrong).
>
> Thanks for the response Dieter.  Just as a response to your statement
> above, in my own testing here, if I set security-policy-implementation C in
> my zope.conf, I am still seeing lines for Verbose security in the profile
> information.  Here is an example.
>
>  ncalls  tottime  percall  cumtime  percall filename:lineno(function)
> 19567    0.740    0.000   10.300    0.001 VerboseSecurityPolicy.py:57
> (validate)
>
> So it appears to me that Verbose Security overrides the
> security-policy-implementation setting in the zope.conf file.
>
> > >Error Type: Unauthorized
> > >Error Value: You are not allowed to access 'select' in this context
> > >
> > >...last lines in traceback
> > ># PythonScript at /somefunction>
> > >Line 3
> > ># Module Shared.DC.Scripts.Bindings, line 178, in __getattr__
> > >Unauthorized: You are not allowed to access 'select' in this context
> >
> > This exception comes from an "UnauthorizedBinding".
> > It indicates that you try to access a binding
> > ("context", "container", "here", ...) your script does
> > not have rights to.
> >
> > This security tighening was introduced quite late (to fix
> > a security bug). "VerboseSecurity" may be able to disable
> > this tighening.
> >
> > Maybe, the tighening forgets to take proxy roles into account.
> > But this is only a guess. Almost surely, you must debug the
> > situation...
>
> I agree, it looks like further debuging will be required.  What is so odd
> to us, is that visiting the ZMI, going to the proxy page on the affected
> object and re-saving it fixes the problem.  This makes the proxy settings
> "stick" even though the settings do not appear to be lost.  We can see in
> the properties file on the file system that the proxy settings are there.
> Perhaps there is a bug in how Apelib loads proxy settings when it pulls an
> object from the file system.
>
> -Chris

I'm responding to myself to finalize this thread in case anyone else runs into 
this problem.

Line 212&213 in Products/Ape/lib/apelib/zope2/security.py read (deserialize)

        if proxy_roles:
            obj._proxy_roles = proxy_roles

by changing these lines to be

        if proxy_roles:
            obj._proxy_roles = tuple(proxy_roles)

we no longer get the phantom disappearing proxy role issue.

Evidently, the standard C-based zope security requires that the proxy role 
list be a tuple and not a list as Apelib creates it as.  When running with 
Verbose Security and Apelib, Verbose Security works fine with the proxy_roles 
being a list.  As soon as you remove Verbose Security the proxy roles are no 
longer being correctly put back on the objects as far as the C based security 
machinery goes when they are deserialized.  They show correctly through the 
interface, but appear to be ignored by the security machinery.

Finally, updating the objects through the zmi runs the manage_proxy function 
which takes the list of roles and turns them into a tuple.  As long as that 
object stays in the ram cache, it will run fine.

The bug is in Apelib and is masked by Verbose Security which appears to be 
more forgiving as to how the proxy roles list is encoded.

-Chris