From ceb1eec8291175686d0208e66595ff83bc0624e2 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 10 Oct 2007 15:45:52 -0700 Subject: [IPSEC]: Move IP length/checksum setting out of transforms This patch moves the setting of the IP length and checksum fields out of the transforms and into the xfrmX_output functions. This would help future efforts in merging the transforms themselves. It also adds an optimisation to ipcomp due to the fact that the transport offset is guaranteed to be zero. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/ipv6/ipcomp6.c | 19 ++++++------------- 1 file changed, 6 insertions(+), 13 deletions(-) (limited to 'net/ipv6/ipcomp6.c') diff --git a/net/ipv6/ipcomp6.c b/net/ipv6/ipcomp6.c index 8f3f32faaf4c..28fc8edfdc3a 100644 --- a/net/ipv6/ipcomp6.c +++ b/net/ipv6/ipcomp6.c @@ -119,20 +119,15 @@ out: static int ipcomp6_output(struct xfrm_state *x, struct sk_buff *skb) { int err; - struct ipv6hdr *top_iph; struct ip_comp_hdr *ipch; struct ipcomp_data *ipcd = x->data; int plen, dlen; u8 *start, *scratch; struct crypto_comp *tfm; int cpu; - int hdr_len; - - skb_push(skb, -skb_network_offset(skb)); - hdr_len = skb_transport_offset(skb); /* check whether datagram len is larger than threshold */ - if ((skb->len - hdr_len) < ipcd->threshold) { + if (skb->len < ipcd->threshold) { goto out_ok; } @@ -140,9 +135,9 @@ static int ipcomp6_output(struct xfrm_state *x, struct sk_buff *skb) goto out_ok; /* compression */ - plen = skb->len - hdr_len; + plen = skb->len; dlen = IPCOMP_SCRATCH_SIZE; - start = skb_transport_header(skb); + start = skb->data; cpu = get_cpu(); scratch = *per_cpu_ptr(ipcomp6_scratches, cpu); @@ -155,13 +150,9 @@ static int ipcomp6_output(struct xfrm_state *x, struct sk_buff *skb) } memcpy(start + sizeof(struct ip_comp_hdr), scratch, dlen); put_cpu(); - pskb_trim(skb, hdr_len + dlen + sizeof(struct ip_comp_hdr)); + pskb_trim(skb, dlen + sizeof(struct ip_comp_hdr)); /* insert ipcomp header and replace datagram */ - top_iph = ipv6_hdr(skb); - - top_iph->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); - ipch = ip_comp_hdr(skb); ipch->nexthdr = *skb_mac_header(skb); ipch->flags = 0; @@ -169,6 +160,8 @@ static int ipcomp6_output(struct xfrm_state *x, struct sk_buff *skb) *skb_mac_header(skb) = IPPROTO_COMP; out_ok: + skb_push(skb, -skb_network_offset(skb)); + return 0; } -- cgit v1.2.3-59-g8ed1b