xfrm: Add xfrm_tunnel_skb_cb to the skb common buffer
IPsec vti_rcv needs to remind the tunnel pointer to
check it later at the vti_rcv_cb callback. So add
this pointer to the IPsec common buffer, initialize
it and check it to avoid transport state matching of
a tunneled packet.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 345a150..3311259 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -599,16 +599,27 @@
int xfrm_register_km(struct xfrm_mgr *km);
int xfrm_unregister_km(struct xfrm_mgr *km);
+struct xfrm_tunnel_skb_cb {
+ union {
+ struct inet_skb_parm h4;
+ struct inet6_skb_parm h6;
+ } header;
+
+ union {
+ struct ip_tunnel *ip4;
+ struct ip6_tnl *ip6;
+ } tunnel;
+};
+
+#define XFRM_TUNNEL_SKB_CB(__skb) ((struct xfrm_tunnel_skb_cb *)&((__skb)->cb[0]))
+
/*
* This structure is used for the duration where packets are being
* transformed by IPsec. As soon as the packet leaves IPsec the
* area beyond the generic IP part may be overwritten.
*/
struct xfrm_skb_cb {
- union {
- struct inet_skb_parm h4;
- struct inet6_skb_parm h6;
- } header;
+ struct xfrm_tunnel_skb_cb header;
/* Sequence number for replay protection. */
union {
@@ -630,10 +641,7 @@
* to transmit header information to the mode input/output functions.
*/
struct xfrm_mode_skb_cb {
- union {
- struct inet_skb_parm h4;
- struct inet6_skb_parm h6;
- } header;
+ struct xfrm_tunnel_skb_cb header;
/* Copied from header for IPv4, always set to zero and DF for IPv6. */
__be16 id;
@@ -665,10 +673,7 @@
* related information.
*/
struct xfrm_spi_skb_cb {
- union {
- struct inet_skb_parm h4;
- struct inet6_skb_parm h6;
- } header;
+ struct xfrm_tunnel_skb_cb header;
unsigned int daddroff;
unsigned int family;
@@ -1510,6 +1515,7 @@
static inline int xfrm4_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi)
{
+ XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL;
XFRM_SPI_SKB_CB(skb)->family = AF_INET;
XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr);
return xfrm_input(skb, nexthdr, spi, 0);
@@ -1781,4 +1787,24 @@
return 0;
}
+static inline int xfrm_tunnel_check(struct sk_buff *skb, struct xfrm_state *x,
+ unsigned int family)
+{
+ bool tunnel = false;
+
+ switch(family) {
+ case AF_INET:
+ if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
+ tunnel = true;
+ break;
+ case AF_INET6:
+ if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
+ tunnel = true;
+ break;
+ }
+ if (tunnel && !(x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL))
+ return -EINVAL;
+
+ return 0;
+}
#endif /* _NET_XFRM_H */