android_kernel_sony_msm8994/net/ipv6/ip6_checksum.c
Cong Wang acb3e04119 ipv6: move csum_ipv6_magic() and udp6_csum_init() into static library
As suggested by David, udp6_csum_init() is too big to be inlined,
move it to ipv6 static library, net/ipv6/ip6_checksum.c.

And the generic csum_ipv6_magic() too.

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-08 17:56:10 -08:00

98 lines
2.3 KiB
C

#include <net/ip.h>
#include <net/udp.h>
#include <net/udplite.h>
#include <asm/checksum.h>
#ifndef _HAVE_ARCH_IPV6_CSUM
__sum16 csum_ipv6_magic(const struct in6_addr *saddr,
const struct in6_addr *daddr,
__u32 len, unsigned short proto,
__wsum csum)
{
int carry;
__u32 ulen;
__u32 uproto;
__u32 sum = (__force u32)csum;
sum += (__force u32)saddr->s6_addr32[0];
carry = (sum < (__force u32)saddr->s6_addr32[0]);
sum += carry;
sum += (__force u32)saddr->s6_addr32[1];
carry = (sum < (__force u32)saddr->s6_addr32[1]);
sum += carry;
sum += (__force u32)saddr->s6_addr32[2];
carry = (sum < (__force u32)saddr->s6_addr32[2]);
sum += carry;
sum += (__force u32)saddr->s6_addr32[3];
carry = (sum < (__force u32)saddr->s6_addr32[3]);
sum += carry;
sum += (__force u32)daddr->s6_addr32[0];
carry = (sum < (__force u32)daddr->s6_addr32[0]);
sum += carry;
sum += (__force u32)daddr->s6_addr32[1];
carry = (sum < (__force u32)daddr->s6_addr32[1]);
sum += carry;
sum += (__force u32)daddr->s6_addr32[2];
carry = (sum < (__force u32)daddr->s6_addr32[2]);
sum += carry;
sum += (__force u32)daddr->s6_addr32[3];
carry = (sum < (__force u32)daddr->s6_addr32[3]);
sum += carry;
ulen = (__force u32)htonl((__u32) len);
sum += ulen;
carry = (sum < ulen);
sum += carry;
uproto = (__force u32)htonl(proto);
sum += uproto;
carry = (sum < uproto);
sum += carry;
return csum_fold((__force __wsum)sum);
}
EXPORT_SYMBOL(csum_ipv6_magic);
#endif
int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto)
{
int err;
UDP_SKB_CB(skb)->partial_cov = 0;
UDP_SKB_CB(skb)->cscov = skb->len;
if (proto == IPPROTO_UDPLITE) {
err = udplite_checksum_init(skb, uh);
if (err)
return err;
}
if (uh->check == 0) {
/* RFC 2460 section 8.1 says that we SHOULD log
this error. Well, it is reasonable.
*/
LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
return 1;
}
if (skb->ip_summed == CHECKSUM_COMPLETE &&
!csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
skb->len, proto, skb->csum))
skb->ip_summed = CHECKSUM_UNNECESSARY;
if (!skb_csum_unnecessary(skb))
skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
&ipv6_hdr(skb)->daddr,
skb->len, proto, 0));
return 0;
}
EXPORT_SYMBOL(udp6_csum_init);