• Andrew Morton's avatar
    [PATCH] Light-weight Auditing Framework · f85a96f6
    Andrew Morton authored
    From: Rik Faith <faith@redhat.com>
    
    This patch provides a low-overhead system-call auditing framework for Linux
    that is usable by LSM components (e.g., SELinux).  This is an update of the
    patch discussed in this thread:
    
        http://marc.theaimsgroup.com/?t=107815888100001&r=1&w=2
    
    In brief, it provides for netlink-based logging of audit records that have
    been generated in other parts of the kernel (e.g., SELinux) as well as the
    ability to audit system calls, either independently (using simple
    filtering) or as a compliment to the audit record that another part of the
    kernel generated.
    
    The main goals were to provide system call auditing with 1) as low overhead
    as possible, and 2) without duplicating functionality that is already
    provided by SELinux (and/or other security infrastructures).  This
    framework will work "stand-alone", but is not designed to provide, e.g.,
    CAPP functionality without another security component in place.
    
    This updated patch includes changes from feedback I have received,
    including the ability to compile without CONFIG_NET (and better use of
    tabs, so use -w if you diff against the older patch).
    
    Please see http://people.redhat.com/faith/audit/ for an early example
    user-space client (auditd-0.4.tar.gz) and instructions on how to try it.
    
    My future intentions at the kernel level include improving filtering (e.g.,
    syscall personality/exit codes) and syscall support for more architectures.
     First, though, I'm going to work on documentation, a (real) audit daemon,
    and patches for other user-space tools so that people can play with the
    framework and understand how it can be used with and without SELinux.
    
    
    Update:
    
    Light-weight Auditing Framework receive filter fixes
    From: Rik Faith <faith@redhat.com>
    
    Since audit_receive_filter() is only called with audit_netlink_sem held, it
    cannot race with either audit_del_rule() or audit_add_rule(), so the
    list_for_each_entry_rcu()s may be replaced by list_for_each_entry()s, and
    the rcu_read_{un,}lock()s removed.  A fix for this is part of the attached
    patch.
    
    Other features of the attached patch are:
    
    1) generalized the ability to test for inequality
    
    2) added syscall exit status reporting and testing
    
    3) added ability to report and test first 4 syscall arguments (this adds
       a large amount of flexibility for little cost; not implemented or tested
       on ppc64)
    
    4) added ability to report and test personality
    
    User-space demo program enhanced for new fields and inequality testing:
    http://people.redhat.com/faith/audit/auditd-0.5.tar.gz
    f85a96f6
namei.c 56.1 KB