[IPV4]: Add ip_local_out
Most callers of the LOCAL_OUT chain will set the IP packet length and
header checksum before doing so. They also share the same output
function dst_output.
This patch creates a new function called ip_local_out which does all
of that and converts the appropriate users over to it.
Apart from removing duplicate code, it will also help in merging the
IPsec output path once the same thing is done for IPv6.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index bc9e575..03b9b06 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -91,6 +91,28 @@
iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
}
+int __ip_local_out(struct sk_buff *skb)
+{
+ struct iphdr *iph = ip_hdr(skb);
+
+ iph->tot_len = htons(skb->len);
+ ip_send_check(iph);
+ return nf_hook(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, skb->dst->dev,
+ dst_output);
+}
+
+int ip_local_out(struct sk_buff *skb)
+{
+ int err;
+
+ err = __ip_local_out(skb);
+ if (likely(err == 1))
+ err = dst_output(skb);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(ip_local_out);
+
/* dev_loopback_xmit for use with netfilter. */
static int ip_dev_loopback_xmit(struct sk_buff *newskb)
{
@@ -138,20 +160,17 @@
iph->daddr = rt->rt_dst;
iph->saddr = rt->rt_src;
iph->protocol = sk->sk_protocol;
- iph->tot_len = htons(skb->len);
ip_select_ident(iph, &rt->u.dst, sk);
if (opt && opt->optlen) {
iph->ihl += opt->optlen>>2;
ip_options_build(skb, opt, daddr, rt, 0);
}
- ip_send_check(iph);
skb->priority = sk->sk_priority;
/* Send it out. */
- return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev,
- dst_output);
+ return ip_local_out(skb);
}
EXPORT_SYMBOL_GPL(ip_build_and_send_pkt);
@@ -347,7 +366,6 @@
skb_reset_network_header(skb);
iph = ip_hdr(skb);
*((__be16 *)iph) = htons((4 << 12) | (5 << 8) | (inet->tos & 0xff));
- iph->tot_len = htons(skb->len);
if (ip_dont_fragment(sk, &rt->u.dst) && !ipfragok)
iph->frag_off = htons(IP_DF);
else
@@ -366,13 +384,9 @@
ip_select_ident_more(iph, &rt->u.dst, sk,
(skb_shinfo(skb)->gso_segs ?: 1) - 1);
- /* Add an IP checksum. */
- ip_send_check(iph);
-
skb->priority = sk->sk_priority;
- return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev,
- dst_output);
+ return ip_local_out(skb);
no_route:
IP_INC_STATS(IPSTATS_MIB_OUTNOROUTES);
@@ -1262,14 +1276,12 @@
ip_options_build(skb, opt, inet->cork.addr, rt, 0);
}
iph->tos = inet->tos;
- iph->tot_len = htons(skb->len);
iph->frag_off = df;
ip_select_ident(iph, &rt->u.dst, sk);
iph->ttl = ttl;
iph->protocol = sk->sk_protocol;
iph->saddr = rt->rt_src;
iph->daddr = rt->rt_dst;
- ip_send_check(iph);
skb->priority = sk->sk_priority;
skb->dst = dst_clone(&rt->u.dst);
@@ -1279,8 +1291,7 @@
skb_transport_header(skb))->type);
/* Netfilter gets whole the not fragmented skb. */
- err = NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL,
- skb->dst->dev, dst_output);
+ err = ip_local_out(skb);
if (err) {
if (err > 0)
err = inet->recverr ? net_xmit_errno(err) : 0;