Re: (ITS#5114) pcache cache results for searches that hit size/timelimit

[ando@sys-net.it]

rhafer@suse.de wrote:
> On Wednesday 29 August 2007 18:48, ando@sys-net.it wrote:
>> rhafer@suse.de wrote:
>>> But a malicous client can then just send requests with sizelimit 1. Those
>>> query will get cached and the database is of no real use anymore (IMO).
>> Well, in this case, the proxycache should either change the sizelimit
>> (and the timelimit) to unlimited, and deal with client-requested limits
>> locally,
> This seems like the nicest approach to solve the problem. But seems to be a 
> bit more effort.

I'd go this way, yes.

> My suggest for a quick fix for this issue would be to just not cache queries 
> that return one off the _LIMIT_EXCEEDED error codes. Probably with checking 
> if it was a client-requested limit or a limit of the server side (in which 
> case we could probably cache the results).

Then please make a clear statement in the code that it's a temporary
workaround, so it is easier to spot and remove, eventually.

>> or consider uncacheable those requests that specify a time or a 
>> size limit.
> Well that would cause even those queries being uncachable that would not hit 
> the requested limit. If I understand you correctly.

Right.  Well, I understand if no limit was hit the request would become
cacheable.  In this case, the approach you suggest would be fine.

p.



Ing. Pierangelo Masarati
OpenLDAP Core Team

SysNet s.r.l.
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