xfrm: avoid extract_output indirection for ipv4
We can use a direct call for ipv4, so move the needed functions
to net/xfrm/xfrm_output.c and call them directly.
For ipv6 the indirection can be avoided as well but it will need
a bit more work -- to ease review it will be done in another patch.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index 2fd3d99..a7b3af7 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -13,6 +13,7 @@
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <net/dst.h>
+#include <net/icmp.h>
#include <net/inet_ecn.h>
#include <net/xfrm.h>
@@ -609,6 +610,47 @@ int xfrm_output(struct sock *sk, struct sk_buff *skb)
}
EXPORT_SYMBOL_GPL(xfrm_output);
+static int xfrm4_tunnel_check_size(struct sk_buff *skb)
+{
+ int mtu, ret = 0;
+
+ if (IPCB(skb)->flags & IPSKB_XFRM_TUNNEL_SIZE)
+ goto out;
+
+ if (!(ip_hdr(skb)->frag_off & htons(IP_DF)) || skb->ignore_df)
+ goto out;
+
+ mtu = dst_mtu(skb_dst(skb));
+ if ((!skb_is_gso(skb) && skb->len > mtu) ||
+ (skb_is_gso(skb) &&
+ !skb_gso_validate_network_len(skb, ip_skb_dst_mtu(skb->sk, skb)))) {
+ skb->protocol = htons(ETH_P_IP);
+
+ if (skb->sk)
+ xfrm_local_error(skb, mtu);
+ else
+ icmp_send(skb, ICMP_DEST_UNREACH,
+ ICMP_FRAG_NEEDED, htonl(mtu));
+ ret = -EMSGSIZE;
+ }
+out:
+ return ret;
+}
+
+static int xfrm4_extract_output(struct xfrm_state *x, struct sk_buff *skb)
+{
+ int err;
+
+ err = xfrm4_tunnel_check_size(skb);
+ if (err)
+ return err;
+
+ XFRM_MODE_SKB_CB(skb)->protocol = ip_hdr(skb)->protocol;
+
+ xfrm4_extract_header(skb);
+ return 0;
+}
+
static int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb)
{
const struct xfrm_state_afinfo *afinfo;
@@ -624,6 +666,10 @@ static int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb)
if (inner_mode == NULL)
return -EAFNOSUPPORT;
+ switch (inner_mode->family) {
+ case AF_INET:
+ return xfrm4_extract_output(x, skb);
+ }
rcu_read_lock();
afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
if (likely(afinfo))