diff options
Diffstat (limited to 'net/core/utils.c')
| -rw-r--r-- | net/core/utils.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/net/core/utils.c b/net/core/utils.c index 0bf17da40d52..34459c4c740c 100644 --- a/net/core/utils.c +++ b/net/core/utils.c @@ -293,3 +293,19 @@ out: } EXPORT_SYMBOL(in6_pton); + +void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb, + __be32 from, __be32 to, int pseudohdr) +{ + __be32 diff[] = { ~from, to }; + 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_replace4); |