[PATCH ghak90 V6 04/10] audit: log container info of syscalls

Richard Guy Briggs
2019-04-09T03:40:39Z

Create a new audit record AUDIT_CONTAINER_ID to document the audit
container identifier of a process if it is present.

Called from audit_log_exit(), syscalls are covered.

A sample raw event:
type=SYSCALL msg=audit(1519924845.499:257): arch=c000003e syscall=257 success=yes exit=3 a0=ffffff9c a1=56374e1cef30 a2=241 a3=1b6 items=2 ppid=606 pid=635 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts0 ses=3 comm="bash" exe="/usr/bin/bash" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key="tmpcontainerid"
type=CWD msg=audit(1519924845.499:257): cwd="/root"
type=PATH msg=audit(1519924845.499:257): item=0 name="/tmp/" inode=13863 dev=00:27 mode=041777 ouid=0 ogid=0 rdev=00:00 obj=system_u:object_r:tmp_t:s0 nametype= PARENT cap_fp=0 cap_fi=0 cap_fe=0 cap_fver=0
type=PATH msg=audit(1519924845.499:257): item=1 name="/tmp/tmpcontainerid" inode=17729 dev=00:27 mode=0100644 ouid=0 ogid=0 rdev=00:00 obj=unconfined_u:object_r:user_tmp_t:s0 nametype=CREATE cap_fp=0 cap_fi=0 cap_fe=0 cap_fver=0
type=PROCTITLE msg=audit(1519924845.499:257): proctitle=62617368002D6300736C65657020313B206563686F2074657374203E202F746D702F746D70636F6E7461696E65726964
type=CONTAINER_ID msg=audit(1519924845.499:257): contid=123458

Please see the github audit kernel issue for the main feature:
https://github.com/linux-audit/audit-kernel/issues/90
Please see the github audit userspace issue for supporting additions:
https://github.com/linux-audit/audit-userspace/issues/51
Please see the github audit testsuiite issue for the test case:
https://github.com/linux-audit/audit-testsuite/issues/64
Please see the github audit wiki for the feature overview:
https://github.com/linux-audit/audit-kernel/wiki/RFE-Audit-Container-ID
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Acked-by: Steve Grubb <sgrubb@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
---
include/linux/audit.h | 5 +++++
include/uapi/linux/audit.h | 1 +
kernel/audit.c | 20 ++++++++++++++++++++
kernel/auditsc.c | 20 ++++++++++++++------
4 files changed, 40 insertions(+), 6 deletions(-)

diff --git a/include/linux/audit.h b/include/linux/audit.h
index 301337776193..43438192ca2a 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -199,6 +199,8 @@ static inline u64 audit_get_contid(struct task_struct *tsk)
return tsk->audit->contid;
}

+extern void audit_log_contid(struct audit_context *context, u64 contid);
+
extern u32 audit_enabled;
#else /* CONFIG_AUDIT */
static inline int audit_alloc(struct task_struct *task)
@@ -265,6 +267,9 @@ static inline u64 audit_get_contid(struct task_struct *tsk)
return AUDIT_CID_UNSET;
}

+static inline void audit_log_contid(struct audit_context *context, u64 contid)
+{ }
+
#define audit_enabled AUDIT_OFF
#endif /* CONFIG_AUDIT */

diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h
index 4a6a8bf1de32..55fde9970762 100644
--- a/include/uapi/linux/audit.h
+++ b/include/uapi/linux/audit.h
@@ -115,6 +115,7 @@
#define AUDIT_REPLACE 1329 /* Replace auditd if this packet unanswerd */
#define AUDIT_KERN_MODULE 1330 /* Kernel Module events */
#define AUDIT_FANOTIFY 1331 /* Fanotify access decision */
+#define AUDIT_CONTAINER_ID 1332 /* Container ID */

#define AUDIT_AVC 1400 /* SE Linux avc denial or grant */
#define AUDIT_SELINUX_ERR 1401 /* Internal SE Linux Errors */
diff --git a/kernel/audit.c b/kernel/audit.c
index 182b0f2c183d..3e0af53f3c4d 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -2127,6 +2127,26 @@ void audit_log_session_info(struct audit_buffer *ab)
audit_log_format(ab, "auid=%u ses=%u", auid, sessionid);
}

+/*
+ * audit_log_contid - report container info
+ * @context: task or local context for record
+ * @contid: container ID to report
+ */
+void audit_log_contid(struct audit_context *context, u64 contid)
+{
+ struct audit_buffer *ab;
+
+ if (!audit_contid_valid(contid))
+ return;
+ /* Generate AUDIT_CONTAINER_ID record with container ID */
+ ab = audit_log_start(context, GFP_KERNEL, AUDIT_CONTAINER_ID);
+ if (!ab)
+ return;
+ audit_log_format(ab, "contid=%llu", (unsigned long long)contid);
+ audit_log_end(ab);
+}
+EXPORT_SYMBOL(audit_log_contid);
+
void audit_log_key(struct audit_buffer *ab, char *key)
{
audit_log_format(ab, " key=");
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 1f7edf035b16..eea445b7a181 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1523,7 +1523,7 @@ static void audit_log_exit(void)
for (aux = context->aux_pids; aux; aux = aux->next) {
struct audit_aux_data_pids *axs = (void *)aux;

- for (i = 0; i < axs->pid_count; i++)
+ for (i = 0; i < axs->pid_count; i++) {
if (audit_log_pid_context(context, axs->target_pid[i],
axs->target_auid[i],
axs->target_uid[i],
@@ -1531,14 +1531,20 @@ static void audit_log_exit(void)
axs->target_sid[i],
axs->target_comm[i]))
call_panic = 1;
+ audit_log_contid(context, axs->target_cid[i]);
+ }
}

- if (context->target_pid &&
- audit_log_pid_context(context, context->target_pid,
- context->target_auid, context->target_uid,
- context->target_sessionid,
- context->target_sid, context->target_comm))
+ if (context->target_pid) {
+ if (audit_log_pid_context(context, context->target_pid,
+ context->target_auid,
+ context->target_uid,
+ context->target_sessionid,
+ context->target_sid,
+ context->target_comm))
call_panic = 1;
+ audit_log_contid(context, context->target_cid);
+ }

if (context->pwd.dentry && context->pwd.mnt) {
ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
@@ -1557,6 +1563,8 @@ static void audit_log_exit(void)

audit_log_proctitle();

+ audit_log_contid(context, audit_get_contid(current));
+
/* Send end of event record to help user space know we are finished */
ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
if (ab)
--
1.8.3.1