Re: AUDIT_SIGNAL_INFO

[Matthew Booth <mbooth@redhat.com>]

Eric Paris wrote:
> On Mon, 2009-03-23 at 15:29 +0000, Matthew Booth wrote:
>> Under what circumstances will the RHEL 4 kernel generate a message of
>> type AUDIT_SIGNAL_INFO? My understanding is that it should be sent when
>> a process sends a signal to the audit daemon, however I have not
>> observed that. Any ideas?
> 
> AUDIT_SIGNAL_INFO is sent when the kernel gets an AUDIT_SIGNAL_INFO
> request from auditd.
> 
> Basically if you send a signal to the audit daemon, the audit daemon
> sends a message to the kernel requesting AUDIT_SIGNAL_INFO.  The kernel
> sends the info back to auditd.  Auditd then uses that info to log about
> the signal it took.  auditd then acts on the signal it took.
> 
> So you wouldn't see it in the normal audit logs.  it's really just a
> communication medium between the kernel and auditd.

That makes sense. Looking in libaudit.h, I assume you end up with one of
these:

/* data structure for who signaled the audit daemon */
struct audit_sig_info {
        uid_t           uid;
        pid_t           pid;
    char        ctx[0];
};

Does this give any information in addition to what you'd get from
siginfo_t, or is it inherently more reliable?

Also, is there any way to notice you were sent a KILL or a STOP?

Thanks,

Matt
-- 
Matthew Booth, RHCA, RHCSS
Red Hat, Global Professional Services

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