ndisc: Defer building IPv6 header.

Build ICMPv6 message first and make buffer management easier;
we can use skb->len when filling checksum in ICMPv6 header,
and then build IP header with length field.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
YOSHIFUJI Hideaki / 吉藤英明 2013-01-21 06:48:39 +00:00 committed by David S. Miller
parent af9a997629
commit 527a150fb2

View file

@ -387,7 +387,7 @@ static struct sk_buff *ndisc_alloc_skb(struct net_device *dev,
skb->protocol = htons(ETH_P_IPV6);
skb->dev = dev;
skb_reserve(skb, hlen);
skb_reserve(skb, hlen + sizeof(struct ipv6hdr));
return skb;
}
@ -399,8 +399,8 @@ static void ip6_nd_hdr(struct sk_buff *skb,
{
struct ipv6hdr *hdr;
skb_push(skb, sizeof(*hdr));
skb_reset_network_header(skb);
skb_put(skb, sizeof(struct ipv6hdr));
hdr = ipv6_hdr(skb);
ip6_flow_hdr(hdr, 0, 0);
@ -438,8 +438,6 @@ static struct sk_buff *ndisc_build_skb(struct net_device *dev,
if (!skb)
return NULL;
ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, len);
skb->transport_header = skb->tail;
skb_put(skb, len);
@ -455,10 +453,12 @@ static struct sk_buff *ndisc_build_skb(struct net_device *dev,
if (llinfo)
ndisc_fill_addr_option(opt, llinfo, dev->dev_addr, dev);
hdr->icmp6_cksum = csum_ipv6_magic(saddr, daddr, len,
hdr->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len,
IPPROTO_ICMPV6,
csum_partial(hdr,
len, 0));
skb->len, 0));
ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len);
return skb;
}
@ -1479,9 +1479,6 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
if (!buff)
goto release;
ip6_nd_hdr(buff, &saddr_buf, &ipv6_hdr(skb)->saddr,
inet6_sk(sk)->hop_limit, len);
skb_set_transport_header(buff, skb_tail_pointer(buff) - buff->data);
skb_put(buff, len);
msg = (struct rd_msg *)icmp6_hdr(buff);
@ -1513,8 +1510,11 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
opt = ndisc_fill_redirect_hdr_option(opt, skb, rd_len);
msg->icmph.icmp6_cksum = csum_ipv6_magic(&saddr_buf, &ipv6_hdr(skb)->saddr,
len, IPPROTO_ICMPV6,
csum_partial(msg, len, 0));
buff->len, IPPROTO_ICMPV6,
csum_partial(msg, buff->len, 0));
ip6_nd_hdr(buff, &saddr_buf, &ipv6_hdr(skb)->saddr,
inet6_sk(sk)->hop_limit, buff->len);
skb_dst_set(buff, dst);
rcu_read_lock();