1 files changed, 19 insertions, 74 deletions

diff --git a/net/ipv4/xfrm4_output.c b/net/ipv4/xfrm4_output.c
index 327a617d594c..0ae67d537499 100644
--- a/net/ipv4/xfrm4_output.c
+++ b/net/ipv4/xfrm4_output.c
@@ -1,11 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * xfrm4_output.c - Common IPsec encapsulation code for IPv4.
  * Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
  */
 
 #include <linux/if_ether.h>
@@ -18,84 +14,33 @@
 #include <net/xfrm.h>
 #include <net/icmp.h>
 
-static int xfrm4_tunnel_check_size(struct sk_buff *skb)
+static int __xfrm4_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
-	int mtu, ret = 0;
-	struct dst_entry *dst;
-
-	if (IPCB(skb)->flags & IPSKB_XFRM_TUNNEL_SIZE)
-		goto out;
-
-	if (!(ip_hdr(skb)->frag_off & htons(IP_DF)) || skb->local_df)
-		goto out;
+#ifdef CONFIG_NETFILTER
+	struct xfrm_state *x = skb_dst(skb)->xfrm;
 
-	dst = skb_dst(skb);
-	mtu = dst_mtu(dst);
-	if (skb->len > mtu) {
-		if (skb->sk)
-			ip_local_error(skb->sk, EMSGSIZE, ip_hdr(skb)->daddr,
-				       inet_sk(skb->sk)->inet_dport, mtu);
-		else
-			icmp_send(skb, ICMP_DEST_UNREACH,
-				  ICMP_FRAG_NEEDED, htonl(mtu));
-		ret = -EMSGSIZE;
+	if (!x) {
+		IPCB(skb)->flags |= IPSKB_REROUTED;
+		return dst_output(net, sk, skb);
 	}
-out:
-	return ret;
-}
-
-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;
-
-	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;
-
-	memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
-	IPCB(skb)->flags |= IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED;
-
-	skb->protocol = htons(ETH_P_IP);
+#endif
 
-	return x->outer_mode->output2(x, skb);
+	return xfrm_output(sk, skb);
 }
-EXPORT_SYMBOL(xfrm4_prepare_output);
 
-int xfrm4_output_finish(struct sk_buff *skb)
+int xfrm4_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
-#ifdef CONFIG_NETFILTER
-	if (!skb_dst(skb)->xfrm) {
-		IPCB(skb)->flags |= IPSKB_REROUTED;
-		return dst_output(skb);
-	}
-
-	IPCB(skb)->flags |= IPSKB_XFRM_TRANSFORMED;
-#endif
-
-	skb->protocol = htons(ETH_P_IP);
-	return xfrm_output(skb);
+	return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
+			    net, sk, skb, skb->dev, skb_dst_dev(skb),
+			    __xfrm4_output,
+			    !(IPCB(skb)->flags & IPSKB_REROUTED));
 }
 
-int xfrm4_output(struct sk_buff *skb)
+void xfrm4_local_error(struct sk_buff *skb, u32 mtu)
 {
-	struct dst_entry *dst = skb_dst(skb);
-	struct xfrm_state *x = dst->xfrm;
+	struct iphdr *hdr;
 
-	return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, skb,
-			    NULL, dst->dev,
-			    x->outer_mode->afinfo->output_finish,
-			    !(IPCB(skb)->flags & IPSKB_REROUTED));
+	hdr = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
+	ip_local_error(skb->sk, EMSGSIZE, hdr->daddr,
+		       inet_sk(skb->sk)->inet_dport, mtu);
 }