Re: intercepting syscalls

Daniel Souza
2005-04-15T20:20:09Z

On 4/15/05, Arjan van de Ven <arjan@infradead.org> wrote:
> On Fri, 2005-04-15 at 13:10 -0700, Daniel Souza wrote:
> > You're welcome, Igor. I needed to intercept syscalls in a little
> > project that I were implementing, to keep track of filesystem changes,
>
> I assume you weren't about tracking file content changing... since you
> can't do that with syscall hijacking.. (that is a common misconception
> by people who came from a MS Windows environment and did things like
> anti virus tools there this way)

No, I was tracking file creations/modifications/attemps of
access/directory creations|modifications/file movings/program
executions with some filter exceptions (avoid logging library loads by
ldd to preserve disk space).

It was a little module that logs file changes and program executions
to syslog (showing owner,pid,ppid,process name, return of
operation,etc), that, used with remote syslog logging to a 'strictly
secure' machine (just receive logs), keep security logs of everything
(like, it was possible to see apache running commands as "ls -la /" or
"ps aux", that, in fact, were signs of intrusion of try of intrusion,
because it's not a usual behavior of httpd. Maybe anyone exploited a
php page to execute arbitrary scripts...)

--
# (perl -e "while (1) { print "\x90"; }") | dd of=/dev/evil