[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/include/net/ip.h b/include/net/ip.h
index 50c8889..66d5161 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -102,6 +102,8 @@
extern int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
extern int ip_do_nat(struct sk_buff *skb);
extern void ip_send_check(struct iphdr *ip);
+extern int __ip_local_out(struct sk_buff *skb);
+extern int ip_local_out(struct sk_buff *skb);
extern int ip_queue_xmit(struct sk_buff *skb, int ipfragok);
extern void ip_init(void);
extern int ip_append_data(struct sock *sk,
diff --git a/include/net/ipip.h b/include/net/ipip.h
index 7cdc914..549e132 100644
--- a/include/net/ipip.h
+++ b/include/net/ipip.h
@@ -2,6 +2,7 @@
#define __NET_IPIP_H 1
#include <linux/if_tunnel.h>
+#include <net/ip.h>
/* Keep error state on tunnel for 30 sec */
#define IPTUNNEL_ERR_TIMEO (30*HZ)
@@ -30,11 +31,9 @@
int pkt_len = skb->len; \
\
skb->ip_summed = CHECKSUM_NONE; \
- iph->tot_len = htons(skb->len); \
ip_select_ident(iph, &rt->u.dst, NULL); \
- ip_send_check(iph); \
\
- err = NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev, dst_output);\
+ err = ip_local_out(skb); \
if (net_xmit_eval(err) == 0) { \
stats->tx_bytes += pkt_len; \
stats->tx_packets++; \
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 7015585..c560a93 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -349,17 +349,12 @@
static int igmpv3_sendpack(struct sk_buff *skb)
{
- struct iphdr *pip = ip_hdr(skb);
struct igmphdr *pig = igmp_hdr(skb);
- const int iplen = skb->tail - skb->network_header;
const int igmplen = skb->tail - skb->transport_header;
- pip->tot_len = htons(iplen);
- ip_send_check(pip);
pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
- return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, skb->dev,
- dst_output);
+ return ip_local_out(skb);
}
static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
@@ -680,13 +675,11 @@
iph->daddr = dst;
iph->saddr = rt->rt_src;
iph->protocol = IPPROTO_IGMP;
- iph->tot_len = htons(IGMP_SIZE);
ip_select_ident(iph, &rt->u.dst, NULL);
((u8*)&iph[1])[0] = IPOPT_RA;
((u8*)&iph[1])[1] = 4;
((u8*)&iph[1])[2] = 0;
((u8*)&iph[1])[3] = 0;
- ip_send_check(iph);
ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
ih->type=type;
@@ -695,8 +688,7 @@
ih->group=group;
ih->csum=ip_compute_csum((void *)ih, sizeof(struct igmphdr));
- return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev,
- dst_output);
+ return ip_local_out(skb);
}
static void igmp_gq_timer_expire(unsigned long data)
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;
diff --git a/net/ipv4/ipvs/ip_vs_xmit.c b/net/ipv4/ipvs/ip_vs_xmit.c
index 7c074e3..66775ad 100644
--- a/net/ipv4/ipvs/ip_vs_xmit.c
+++ b/net/ipv4/ipvs/ip_vs_xmit.c
@@ -16,8 +16,8 @@
*/
#include <linux/kernel.h>
-#include <linux/ip.h>
#include <linux/tcp.h> /* for tcphdr */
+#include <net/ip.h>
#include <net/tcp.h> /* for csum_tcpudp_magic */
#include <net/udp.h>
#include <net/icmp.h> /* for icmp_send */
@@ -406,14 +406,12 @@
iph->daddr = rt->rt_dst;
iph->saddr = rt->rt_src;
iph->ttl = old_iph->ttl;
- iph->tot_len = htons(skb->len);
ip_select_ident(iph, &rt->u.dst, NULL);
- ip_send_check(iph);
/* Another hack: avoid icmp_send in ip_fragment */
skb->local_df = 1;
- IP_VS_XMIT(skb, rt);
+ ip_local_out(skb);
LeaveFunction(10);
diff --git a/net/ipv4/netfilter/ipt_REJECT.c b/net/ipv4/netfilter/ipt_REJECT.c
index dcf4d21..ccb2a03 100644
--- a/net/ipv4/netfilter/ipt_REJECT.c
+++ b/net/ipv4/netfilter/ipt_REJECT.c
@@ -90,7 +90,6 @@
/* Truncate to length (no data) */
tcph->doff = sizeof(struct tcphdr)/4;
skb_trim(nskb, ip_hdrlen(nskb) + sizeof(struct tcphdr));
- niph->tot_len = htons(nskb->len);
if (tcph->ack) {
needs_ack = 0;
@@ -139,18 +138,13 @@
/* Adjust IP TTL */
niph->ttl = dst_metric(nskb->dst, RTAX_HOPLIMIT);
- /* Adjust IP checksum */
- niph->check = 0;
- niph->check = ip_fast_csum(skb_network_header(nskb), niph->ihl);
-
/* "Never happens" */
if (nskb->len > dst_mtu(nskb->dst))
goto free_nskb;
nf_ct_attach(nskb, oldskb);
- NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, nskb, NULL, nskb->dst->dev,
- dst_output);
+ ip_local_out(nskb);
return;
free_nskb:
diff --git a/net/ipv4/xfrm4_output.c b/net/ipv4/xfrm4_output.c
index 13fd113..0ffc3d0 100644
--- a/net/ipv4/xfrm4_output.c
+++ b/net/ipv4/xfrm4_output.c
@@ -69,17 +69,12 @@
static inline int xfrm4_output_one(struct sk_buff *skb)
{
- struct iphdr *iph;
int err;
err = xfrm_output(skb);
if (err)
goto error_nolock;
- iph = ip_hdr(skb);
- iph->tot_len = htons(skb->len);
- ip_send_check(iph);
-
IPCB(skb)->flags |= IPSKB_XFRM_TRANSFORMED;
err = 0;
@@ -97,8 +92,7 @@
while (likely((err = xfrm4_output_one(skb)) == 0)) {
nf_reset(skb);
- err = nf_hook(PF_INET, NF_IP_LOCAL_OUT, skb, NULL,
- skb->dst->dev, dst_output);
+ err = __ip_local_out(skb);
if (unlikely(err != 1))
break;