Tracking IPC calls

Marcus Völp voelp at
Tue Mar 29 09:02:34 CEST 2005

>On Mon Mar 28, 2005 at 17:52:35 -0500, Julian Grizzard wrote:
>>>jdb can log IPC messages into the trace buffer. Enable them with
>>>'I*IR+', look at the trace buffer with 'T'. Is that what you are looking
>>Well that's a start.  What we are trying to do is the same thing
>>programatically.  We want to be able to track IPCs over long periods
>>of time, only storing interesting IPCs.  The short story is that we
>>are working on a number of security applications where this ability
>>would be interesting.  Any pointers on doing the same programatically?
>> Maybe a look at the jdb code would help?
I would like to make just an additional note of warning. The tracebuffer 
should serve your short term needs, also because its content is directly 
at user-level. However, the trace buffer is a debugging feature and 
should be regarded as a security hole in a real-life system. So far we 
have no plans of adding an additional mechanism for securely monitoring 
IPC. The indendet way this should work is by installing a monitor in the 
IPC path using mechanisms somehow comparable to IPC redirection 
( Note, however, 
that this monitoring bears an overhead of an additional IPC and cannot 
be made completely transparent.


Marcus Völp

Department of Computer Science
Institute for System Architecture

Tel: +49 (351) 463-38350
Fax: +49 (351) 463-38284

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