Re: [PATCH ipsec v2 1/3] ipv6: wire up skb->encapsulation
From: Simon Horman <horms@verge.net.au>
Date: 2013-08-20 00:34:04
On Sun, Aug 18, 2013 at 01:46:52PM +0200, Hannes Frederic Sowa wrote:
When pushing a new header before current one call skb_reset_inner_headers to record the position of the inner headers in the various ipv6 tunnel protocols. We later need this to correctly identify the addresses needed to send back an error in the xfrm layer. This change is safe, because skb->protocol is always checked before dereferencing data from the inner protocol.
It seems that the intention is to only track the inner-most header due to the presence of if (likely(!skb->encapsulation)). Is this the intention?
quoted hunk ↗ jump to hunk
v2: a) unchanged Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: YOSHIFUJI Hideaki <redacted> Cc: Nicolas Dichtel <redacted> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Hannes Frederic Sowa <redacted> --- This patch is based on Steffen Klassert's ipsec tree. net/ipv6/ip6_gre.c | 5 +++++ net/ipv6/ip6_tunnel.c | 6 ++++++ net/ipv6/sit.c | 5 +++++ 3 files changed, 16 insertions(+)diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index ecd6073..90747f1 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c@@ -724,6 +724,11 @@ static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb, ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); } + if (likely(!skb->encapsulation)) { + skb_reset_inner_headers(skb); + skb->encapsulation = 1; + } + skb_push(skb, gre_hlen); skb_reset_network_header(skb); skb_set_transport_header(skb, sizeof(*ipv6h));diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c index 1e55866..46ba243 100644 --- a/net/ipv6/ip6_tunnel.c +++ b/net/ipv6/ip6_tunnel.c@@ -1027,6 +1027,12 @@ static int ip6_tnl_xmit2(struct sk_buff *skb, init_tel_txopt(&opt, encap_limit); ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); } + + if (likely(!skb->encapsulation)) { + skb_reset_inner_headers(skb); + skb->encapsulation = 1; + } + skb_push(skb, sizeof(struct ipv6hdr)); skb_reset_network_header(skb); ipv6h = ipv6_hdr(skb);diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index a3437a4..fbfc5a8 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c@@ -888,6 +888,11 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, ttl = iph6->hop_limit; tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6)); + if (likely(!skb->encapsulation)) { + skb_reset_inner_headers(skb); + skb->encapsulation = 1; + } + err = iptunnel_xmit(dev_net(dev), rt, skb, fl4.saddr, fl4.daddr, IPPROTO_IPV6, tos, ttl, df); iptunnel_xmit_stats(err, &dev->stats, dev->tstats);-- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html