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authorPatrick McHardy <kaber@trash.net>2012-08-26 19:14:10 +0200
committerPablo Neira Ayuso <pablo@netfilter.org>2012-08-30 03:00:16 +0200
commit2cf545e835aae92173ef0b1f4af385e9c40f21e8 (patch)
treeb03bf5a155eed859a9852922a4311340a598c725 /net/core/utils.c
parentnetfilter: ipv6: expand skb head in ip6_route_me_harder after oif change (diff)
downloadlinux-dev-2cf545e835aae92173ef0b1f4af385e9c40f21e8.tar.xz
linux-dev-2cf545e835aae92173ef0b1f4af385e9c40f21e8.zip
net: core: add function for incremental IPv6 pseudo header checksum updates
Add inet_proto_csum_replace16 for incrementally updating IPv6 pseudo header checksums for IPv6 NAT. Signed-off-by: Patrick McHardy <kaber@trash.net> Acked-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/utils.c')
-rw-r--r--net/core/utils.c20
1 files changed, 20 insertions, 0 deletions
diff --git a/net/core/utils.c b/net/core/utils.c
index 39895a65e54a..f5613d569c23 100644
--- a/net/core/utils.c
+++ b/net/core/utils.c
@@ -294,6 +294,26 @@ void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
}
EXPORT_SYMBOL(inet_proto_csum_replace4);
+void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb,
+ const __be32 *from, const __be32 *to,
+ int pseudohdr)
+{
+ __be32 diff[] = {
+ ~from[0], ~from[1], ~from[2], ~from[3],
+ to[0], to[1], to[2], to[3],
+ };
+ if (skb->ip_summed != CHECKSUM_PARTIAL) {
+ *sum = csum_fold(csum_partial(diff, sizeof(diff),
+ ~csum_unfold(*sum)));
+ if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
+ skb->csum = ~csum_partial(diff, sizeof(diff),
+ ~skb->csum);
+ } else if (pseudohdr)
+ *sum = ~csum_fold(csum_partial(diff, sizeof(diff),
+ csum_unfold(*sum)));
+}
+EXPORT_SYMBOL(inet_proto_csum_replace16);
+
int mac_pton(const char *s, u8 *mac)
{
int i;