On Tue, Feb 18, 2020 at 3:52 PM Richard Guy Briggs <r...@redhat.com> wrote: > > Log information about programs connecting to and disconnecting from the > audit netlink multicast socket. This is needed so that during > investigations a security officer can tell who or what had access to the > audit trail. This helps to meet the FAU_SAR.2 requirement for Common > Criteria. Here is the systemd startup event: > > type=PROCTITLE msg=audit(2020-02-18 15:26:50.775:10) : proctitle=/init > type=SYSCALL msg=audit(2020-02-18 15:26:50.775:10) : arch=x86_64 syscall=bind > success=yes exit=0 a0=0x19 a1=0x55645c369b70 a2=0xc a3=0x7fff9fedec24 items=0 > ppid=0 pid=1 auid=unset uid=root gid=root euid=root suid=root fsuid=root > egid=root sgid=root fsgid=root tty=(none) ses=unset comm=systemd > exe=/usr/lib/systemd/systemd subj=kernel key=(null) > type=UNKNOWN[1335] msg=audit(2020-02-18 15:26:50.775:10) : pid=1 uid=root > auid=unset tty=(none) ses=unset subj=kernel comm=systemd > exe=/usr/lib/systemd/systemd nl-mcgrp=1 op=connect res=yes > > And the events from the test suite: > > type=PROCTITLE msg=audit(2020-02-18 15:28:01.594:307) : > proctitle=/usr/bin/perl -w amcast_joinpart/test > type=SOCKADDR msg=audit(2020-02-18 15:28:01.594:307) : saddr={ > saddr_fam=netlink nlnk-fam=16 nlnk-pid=0 } > type=SYSCALL msg=audit(2020-02-18 15:28:01.594:307) : arch=x86_64 > syscall=bind success=yes exit=0 a0=0x7 a1=0x558ebc428be0 a2=0xc a3=0x0 > items=0 ppid=642 pid=645 auid=root uid=root gid=root euid=root suid=root > fsuid=root egid=root sgid=root fsgid=root tty=ttyS0 ses=1 comm=perl > exe=/usr/bin/perl subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 > key=(null) > type=UNKNOWN[1335] msg=audit(2020-02-18 15:28:01.594:307) : pid=645 uid=root > auid=root tty=ttyS0 ses=1 > subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 comm=perl > exe=/usr/bin/perl nl-mcgrp=1 op=connect res=yes > > type=UNKNOWN[1335] msg=audit(2020-01-17 10:36:24.051:295) : pid=674 uid=root > auid=root tty=ttyS0 ses=3 > subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 comm=perl > exe=/usr/bin/perl nl-mcgrp=1 op=disconnect res=yes > > Please see the upstream issue tracker: > https://github.com/linux-audit/audit-kernel/issues/28 > > https://github.com/linux-audit/audit-kernel/wiki/RFE-Audit-Multicast-Socket-Join-Part > https://github.com/rgbriggs/audit-testsuite/compare/ghak28-mcast-part-join > > Signed-off-by: Richard Guy Briggs <r...@redhat.com> > > --- > Note: msg type 1334 was skipped due to BPF accepted in another tree. > Note: v5 due to previous 2014-10-07, 2015-07-23, 2016-11-30, 2017-10-13 > Note: subj attrs included due to missing syscall record for systemd (audit=1) > Note: tried refactor of subj attrs, but this is yet another new order. > --- > include/uapi/linux/audit.h | 1 + > kernel/audit.c | 48 > ++++++++++++++++++++++++++++++++++++++++++---- > 2 files changed, 45 insertions(+), 4 deletions(-)
... > diff --git a/kernel/audit.c b/kernel/audit.c > index 17b0d523afb3..478259f3fa53 100644 > --- a/kernel/audit.c > +++ b/kernel/audit.c > @@ -1520,20 +1520,60 @@ static void audit_receive(struct sk_buff *skb) > audit_ctl_unlock(); > } > > +/* Log information about who is connecting to the audit multicast socket */ > +static void audit_log_multicast_bind(int group, const char *op, int err) > +{ Since this is logging both bind and unbind, let's change the name to something a bit more generic, e.g. audit_log_multicast(). > + const struct cred *cred; > + struct tty_struct *tty; > + char comm[sizeof(current->comm)]; > + struct audit_buffer *ab; > + > + if (!audit_enabled) > + return; > + > + ab = audit_log_start(audit_context(), GFP_KERNEL, > AUDIT_EVENT_LISTENER); > + if (!ab) > + return; > + > + cred = current_cred(); > + tty = audit_get_tty(); > + audit_log_format(ab, "pid=%u uid=%u auid=%u tty=%s ses=%u", > + task_pid_nr(current), > + from_kuid(&init_user_ns, cred->uid), > + from_kuid(&init_user_ns, > audit_get_loginuid(current)), > + tty ? tty_name(tty) : "(none)", > + audit_get_sessionid(current)); > + audit_put_tty(tty); > + audit_log_task_context(ab); /* subj= */ > + audit_log_format(ab, " comm="); > + audit_log_untrustedstring(ab, get_task_comm(comm, current)); > + audit_log_d_path_exe(ab, current->mm); /* exe= */ > + audit_log_format(ab, " nl-mcgrp=%d op=%s res=%d", group, op, !err); > + audit_log_end(ab); > +} -- paul moore www.paul-moore.com -- Linux-audit mailing list Linux-audit@redhat.com https://www.redhat.com/mailman/listinfo/linux-audit