[IP]: Introduce ip_hdrlen()
For the common sequence "skb->nh.iph->ihl * 4", removing a good number of open
coded skb->nh.iph uses, now to go after the rest...
Just out of curiosity, here are the idioms found to get the same result:
skb->nh.iph->ihl << 2
skb->nh.iph->ihl<<2
skb->nh.iph->ihl * 4
skb->nh.iph->ihl*4
(skb->nh.iph)->ihl * sizeof(u32)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/netfilter/ipt_REJECT.c b/net/ipv4/netfilter/ipt_REJECT.c
index 80f739e..01c04f0 100644
--- a/net/ipv4/netfilter/ipt_REJECT.c
+++ b/net/ipv4/netfilter/ipt_REJECT.c
@@ -43,7 +43,6 @@
static void send_reset(struct sk_buff *oldskb, int hook)
{
struct sk_buff *nskb;
- struct iphdr *iph = oldskb->nh.iph;
struct tcphdr _otcph, *oth, *tcph;
__be16 tmp_port;
__be32 tmp_addr;
@@ -54,7 +53,7 @@
if (oldskb->nh.iph->frag_off & htons(IP_OFFSET))
return;
- oth = skb_header_pointer(oldskb, oldskb->nh.iph->ihl * 4,
+ oth = skb_header_pointer(oldskb, ip_hdrlen(oldskb),
sizeof(_otcph), &_otcph);
if (oth == NULL)
return;
@@ -64,7 +63,7 @@
return;
/* Check checksum */
- if (nf_ip_checksum(oldskb, hook, iph->ihl * 4, IPPROTO_TCP))
+ if (nf_ip_checksum(oldskb, hook, ip_hdrlen(oldskb), IPPROTO_TCP))
return;
/* We need a linear, writeable skb. We also need to expand
@@ -84,7 +83,7 @@
skb_shinfo(nskb)->gso_segs = 0;
skb_shinfo(nskb)->gso_type = 0;
- tcph = (struct tcphdr *)((u_int32_t*)nskb->nh.iph + nskb->nh.iph->ihl);
+ tcph = (struct tcphdr *)(skb_network_header(nskb) + ip_hdrlen(nskb));
/* Swap source and dest */
tmp_addr = nskb->nh.iph->saddr;
@@ -96,7 +95,7 @@
/* Truncate to length (no data) */
tcph->doff = sizeof(struct tcphdr)/4;
- skb_trim(nskb, nskb->nh.iph->ihl*4 + sizeof(struct tcphdr));
+ skb_trim(nskb, ip_hdrlen(nskb) + sizeof(struct tcphdr));
nskb->nh.iph->tot_len = htons(nskb->len);
if (tcph->ack) {
@@ -105,9 +104,9 @@
tcph->ack_seq = 0;
} else {
needs_ack = 1;
- tcph->ack_seq = htonl(ntohl(oth->seq) + oth->syn + oth->fin
- + oldskb->len - oldskb->nh.iph->ihl*4
- - (oth->doff<<2));
+ tcph->ack_seq = htonl(ntohl(oth->seq) + oth->syn + oth->fin +
+ oldskb->len - ip_hdrlen(oldskb) -
+ (oth->doff << 2));
tcph->seq = 0;
}
@@ -149,7 +148,7 @@
/* Adjust IP checksum */
nskb->nh.iph->check = 0;
- nskb->nh.iph->check = ip_fast_csum((unsigned char *)nskb->nh.iph,
+ nskb->nh.iph->check = ip_fast_csum(skb_network_header(nskb),
nskb->nh.iph->ihl);
/* "Never happens" */
@@ -182,7 +181,7 @@
/* Our naive response construction doesn't deal with IP
options, and probably shouldn't try. */
- if ((*pskb)->nh.iph->ihl<<2 != sizeof(struct iphdr))
+ if (ip_hdrlen(*pskb) != sizeof(struct iphdr))
return NF_DROP;
/* WARNING: This code causes reentry within iptables.