[PATCH ghak90 V6 10/10] audit: NETFILTER_PKT: record each container ID associated with a netNS

Richard Guy Briggs
2019-04-09T03:41:22Z

Add audit container identifier auxiliary record(s) to NETFILTER_PKT
event standalone records. Iterate through all potential audit container
identifiers associated with a network namespace.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
---
include/linux/audit.h | 5 +++++
kernel/audit.c | 39 +++++++++++++++++++++++++++++++++++++++
net/netfilter/nft_log.c | 11 +++++++++--
net/netfilter/xt_AUDIT.c | 11 +++++++++--
4 files changed, 62 insertions(+), 4 deletions(-)

diff --git a/include/linux/audit.h b/include/linux/audit.h
index 4b2503927c37..d43db4491dd1 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -220,6 +220,8 @@ static inline u64 audit_get_contid(struct task_struct *tsk)
extern void audit_netns_contid_del(struct net *net, u64 contid);
extern void audit_switch_task_namespaces(struct nsproxy *ns,
struct task_struct *p);
+extern void audit_log_netns_contid_list(struct net *net,
+ struct audit_context *context);

extern u32 audit_enabled;
#else /* CONFIG_AUDIT */
@@ -296,6 +298,9 @@ static inline void audit_netns_contid_del(struct net *net, u64 contid)
static inline void audit_switch_task_namespaces(struct nsproxy *ns,
struct task_struct *p)
{ }
+static inline void audit_log_netns_contid_list(struct net *net,
+ struct audit_context *context)
+{ }

#define audit_enabled AUDIT_OFF
#endif /* CONFIG_AUDIT */
diff --git a/kernel/audit.c b/kernel/audit.c
index 996213591617..512464a626d1 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -453,6 +453,45 @@ void audit_switch_task_namespaces(struct nsproxy *ns, struct task_struct *p)
audit_netns_contid_add(new->net_ns, contid);
}

+/**
+ * audit_log_netns_contid_list - List contids for the given network namespace
+ * @net: the network namespace of interest
+ * @context: the audit context to use
+ *
+ * Description:
+ * Issues a CONTAINER_ID record with a CSV list of contids associated
+ * with a network namespace to accompany a NETFILTER_PKT record.
+ */
+void audit_log_netns_contid_list(struct net *net, struct audit_context *context)
+{
+ struct audit_buffer *ab = NULL;
+ struct audit_contid *cont;
+ struct audit_net *aunet;
+
+ /* Generate AUDIT_CONTAINER_ID record with container ID CSV list */
+ rcu_read_lock();
+ aunet = net_generic(net, audit_net_id);
+ if (!aunet)
+ goto out;
+ list_for_each_entry_rcu(cont, &aunet->contid_list, list) {
+ if (!ab) {
+ ab = audit_log_start(context, GFP_ATOMIC,
+ AUDIT_CONTAINER_ID);
+ if (!ab) {
+ audit_log_lost("out of memory in audit_log_netns_contid_list");
+ goto out;
+ }
+ audit_log_format(ab, "contid=");
+ } else
+ audit_log_format(ab, ",");
+ audit_log_format(ab, "%llu", (unsigned long long)cont->id);
+ }
+ audit_log_end(ab);
+out:
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(audit_log_netns_contid_list);
+
void audit_panic(const char *message)
{
switch (audit_failure) {
diff --git a/net/netfilter/nft_log.c b/net/netfilter/nft_log.c
index 655187bed5d8..bdb1ec2368a7 100644
--- a/net/netfilter/nft_log.c
+++ b/net/netfilter/nft_log.c
@@ -69,13 +69,16 @@ static void nft_log_eval_audit(const struct nft_pktinfo *pkt)
struct sk_buff *skb = pkt->skb;
struct audit_buffer *ab;
int fam = -1;
+ struct audit_context *context;
+ struct net *net;

if (!audit_enabled)
return;

- ab = audit_log_start(NULL, GFP_ATOMIC, AUDIT_NETFILTER_PKT);
+ context = audit_alloc_local(GFP_ATOMIC);
+ ab = audit_log_start(context, GFP_ATOMIC, AUDIT_NETFILTER_PKT);
if (!ab)
- return;
+ goto errout;

audit_log_format(ab, "mark=%#x", skb->mark);

@@ -102,6 +105,10 @@ static void nft_log_eval_audit(const struct nft_pktinfo *pkt)
audit_log_format(ab, " saddr=? daddr=? proto=-1");

audit_log_end(ab);
+ net = xt_net(&pkt->xt);
+ audit_log_netns_contid_list(net, context);
+errout:
+ audit_free_context(context);
}

static void nft_log_eval(const struct nft_expr *expr,
diff --git a/net/netfilter/xt_AUDIT.c b/net/netfilter/xt_AUDIT.c
index af883f1b64f9..a3e547435f13 100644
--- a/net/netfilter/xt_AUDIT.c
+++ b/net/netfilter/xt_AUDIT.c
@@ -71,10 +71,13 @@ static bool audit_ip6(struct audit_buffer *ab, struct sk_buff *skb)
{
struct audit_buffer *ab;
int fam = -1;
+ struct audit_context *context;
+ struct net *net;

if (audit_enabled == AUDIT_OFF)
- goto errout;
- ab = audit_log_start(NULL, GFP_ATOMIC, AUDIT_NETFILTER_PKT);
+ goto out;
+ context = audit_alloc_local(GFP_ATOMIC);
+ ab = audit_log_start(context, GFP_ATOMIC, AUDIT_NETFILTER_PKT);
if (ab == NULL)
goto errout;

@@ -104,7 +107,11 @@ static bool audit_ip6(struct audit_buffer *ab, struct sk_buff *skb)

audit_log_end(ab);

+ net = xt_net(par);
+ audit_log_netns_contid_list(net, context);
errout:
+ audit_free_context(context);
+out:
return XT_CONTINUE;
}

--
1.8.3.1