xfrm: remove output indirection from xfrm_mode

Same is input indirection.  Only exception: we need to export
xfrm_outer_mode_output for pktgen.

Increases size of vmlinux by about 163 byte:
Before:
   text    data     bss     dec      filename
15730208  6936948 4046908 26714064   vmlinux

After:
15730311  6937008 4046908 26714227   vmlinux

xfrm_inner_extract_output has no more external callers, make it static.

v2: add IS_ENABLED(IPV6) guard in xfrm6_prepare_output
    add two missing breaks in xfrm_outer_mode_output (Sabrina Dubroca)
    add WARN_ON_ONCE for 'call AF_INET6 related output function, but
    CONFIG_IPV6=n' case.
    make xfrm_inner_extract_output static

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

4 files changed, 0 insertions, 39 deletions

diff --git a/net/ipv4/xfrm4_mode_beet.c b/net/ipv4/xfrm4_mode_beet.c
index 264c4c9e2473..f02cc8237d54 100644
--- a/net/ipv4/xfrm4_mode_beet.c
+++ b/net/ipv4/xfrm4_mode_beet.c
@@ -129,7 +129,6 @@ out:
 static struct xfrm_mode xfrm4_beet_mode = {
 	.input2 = xfrm4_beet_input,
 	.output2 = xfrm4_beet_output,
-	.output = xfrm4_prepare_output,
 	.owner = THIS_MODULE,
 	.encap = XFRM_MODE_BEET,
 	.flags = XFRM_MODE_FLAG_TUNNEL,
diff --git a/net/ipv4/xfrm4_mode_transport.c b/net/ipv4/xfrm4_mode_transport.c
index c943d710f302..6f8cf09ff0ef 100644
--- a/net/ipv4/xfrm4_mode_transport.c
+++ b/net/ipv4/xfrm4_mode_transport.c
@@ -14,27 +14,6 @@
 #include <net/xfrm.h>
 #include <net/protocol.h>
 
-/* Add encapsulation header.
- *
- * The IP header will be moved forward to make space for the encapsulation
- * header.
- */
-static int xfrm4_transport_output(struct xfrm_state *x, struct sk_buff *skb)
-{
-	struct iphdr *iph = ip_hdr(skb);
-	int ihl = iph->ihl * 4;
-
-	skb_set_inner_transport_header(skb, skb_transport_offset(skb));
-
-	skb_set_network_header(skb, -x->props.header_len);
-	skb->mac_header = skb->network_header +
-			  offsetof(struct iphdr, protocol);
-	skb->transport_header = skb->network_header + ihl;
-	__skb_pull(skb, ihl);
-	memmove(skb_network_header(skb), iph, ihl);
-	return 0;
-}
-
 static struct sk_buff *xfrm4_transport_gso_segment(struct xfrm_state *x,
 						   struct sk_buff *skb,
 						   netdev_features_t features)
@@ -65,7 +44,6 @@ static void xfrm4_transport_xmit(struct xfrm_state *x, struct sk_buff *skb)
 }
 
 static struct xfrm_mode xfrm4_transport_mode = {
-	.output = xfrm4_transport_output,
 	.gso_segment = xfrm4_transport_gso_segment,
 	.xmit = xfrm4_transport_xmit,
 	.owner = THIS_MODULE,
diff --git a/net/ipv4/xfrm4_mode_tunnel.c b/net/ipv4/xfrm4_mode_tunnel.c
index 678b91754b5e..823bc54b47de 100644
--- a/net/ipv4/xfrm4_mode_tunnel.c
+++ b/net/ipv4/xfrm4_mode_tunnel.c
@@ -124,7 +124,6 @@ static void xfrm4_mode_tunnel_xmit(struct xfrm_state *x, struct sk_buff *skb)
 static struct xfrm_mode xfrm4_tunnel_mode = {
 	.input2 = xfrm4_mode_tunnel_input,
 	.output2 = xfrm4_mode_tunnel_output,
-	.output = xfrm4_prepare_output,
 	.gso_segment = xfrm4_mode_tunnel_gso_segment,
 	.xmit = xfrm4_mode_tunnel_xmit,
 	.owner = THIS_MODULE,
diff --git a/net/ipv4/xfrm4_output.c b/net/ipv4/xfrm4_output.c
index be980c195fc5..6802d1aee424 100644
--- a/net/ipv4/xfrm4_output.c
+++ b/net/ipv4/xfrm4_output.c
@@ -58,21 +58,6 @@ int xfrm4_extract_output(struct xfrm_state *x, struct sk_buff *skb)
 	return xfrm4_extract_header(skb);
 }
 
-int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
-{
-	int err;
-
-	err = xfrm_inner_extract_output(x, skb);
-	if (err)
-		return err;
-
-	IPCB(skb)->flags |= IPSKB_XFRM_TUNNEL_SIZE;
-	skb->protocol = htons(ETH_P_IP);
-
-	return x->outer_mode->output2(x, skb);
-}
-EXPORT_SYMBOL(xfrm4_prepare_output);
-
 int xfrm4_output_finish(struct sock *sk, struct sk_buff *skb)
 {
 	memset(IPCB(skb), 0, sizeof(*IPCB(skb)));