[XFRM]: RFC4303 compliant auditing

This patch adds a number of new IPsec audit events to meet the auditing
requirements of RFC4303.  This includes audit hooks for the following events:

 * Could not find a valid SA [sections 2.1, 3.4.2]
   . xfrm_audit_state_notfound()
   . xfrm_audit_state_notfound_simple()

 * Sequence number overflow [section 3.3.3]
   . xfrm_audit_state_replay_overflow()

 * Replayed packet [section 3.4.3]
   . xfrm_audit_state_replay()

 * Integrity check failure [sections 3.4.4.1, 3.4.4.2]
   . xfrm_audit_state_icvfail()

While RFC4304 deals only with ESP most of the changes in this patch apply to
IPsec in general, i.e. both AH and ESP.  The one case, integrity check
failure, where ESP specific code had to be modified the same was done to the
AH code for the sake of consistency.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 3 insertions, 1 deletions

diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index 1b51d1eedbde..2d32772c87c3 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -381,7 +381,7 @@ static int ah6_input(struct xfrm_state *x, struct sk_buff *skb)
                 if (err)
                         goto unlock;
                 if (memcmp(ahp->work_icv, auth_data, ahp->icv_trunc_len)) {
-                        LIMIT_NETDEBUG(KERN_WARNING "ipsec ah authentication error\n");
+                        xfrm_audit_state_icvfail(x, skb, IPPROTO_AH);
                         err = -EBADMSG;
                 }
         }
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 5bd5292ad9fa..e10f10bfe2c9 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -186,6 +186,7 @@ static int esp6_input(struct xfrm_state *x, struct sk_buff *skb)
                         BUG();
 
                 if (unlikely(memcmp(esp->auth.work_icv, sum, alen))) {
+                        xfrm_audit_state_icvfail(x, skb, IPPROTO_ESP);
                         ret = -EBADMSG;
                         goto unlock;
                 }
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index 6644fc6d5427..063ce6ed1bd0 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -152,6 +152,7 @@ int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
 
         if (!x) {
                 XFRM_INC_STATS(LINUX_MIB_XFRMINNOSTATES);
+                xfrm_audit_state_notfound_simple(skb, AF_INET6);
                 goto drop;
         }