diff options
author | Eric W. Biederman <ebiederm@xmission.com> | 2015-09-15 20:04:16 -0500 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2015-09-17 17:18:37 -0700 |
commit | 29a26a56803855a79dbd028cd61abee56237d6e5 (patch) | |
tree | 89fb3a95216d44417577e218a967ede09d676922 /net/ipv4/ip_output.c | |
parent | 04eb44890e5bb3cc855e5c0f18a05eb7311364b7 (diff) | |
download | linux-29a26a56803855a79dbd028cd61abee56237d6e5.tar.bz2 |
netfilter: Pass struct net into the netfilter hooks
Pass a network namespace parameter into the netfilter hooks. At the
call site of the netfilter hooks the path a packet is taking through
the network stack is well known which allows the network namespace to
be easily and reliabily.
This allows the replacement of magic code like
"dev_net(state->in?:state->out)" that appears at the start of most
netfilter hooks with "state->net".
In almost all cases the network namespace passed in is derived
from the first network device passed in, guaranteeing those
paths will not see any changes in practice.
The exceptions are:
xfrm/xfrm_output.c:xfrm_output_resume() xs_net(skb_dst(skb)->xfrm)
ipvs/ip_vs_xmit.c:ip_vs_nat_send_or_cont() ip_vs_conn_net(cp)
ipvs/ip_vs_xmit.c:ip_vs_send_or_cont() ip_vs_conn_net(cp)
ipv4/raw.c:raw_send_hdrinc() sock_net(sk)
ipv6/ip6_output.c:ip6_xmit() sock_net(sk)
ipv6/ndisc.c:ndisc_send_skb() dev_net(skb->dev) not dev_net(dst->dev)
ipv6/raw.c:raw6_send_hdrinc() sock_net(sk)
br_netfilter_hooks.c:br_nf_pre_routing_finish() dev_net(skb->dev) before skb->dev is set to nf_bridge->physindev
In all cases these exceptions seem to be a better expression for the
network namespace the packet is being processed in then the historic
"dev_net(in?in:out)". I am documenting them in case something odd
pops up and someone starts trying to track down what happened.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/ip_output.c')
-rw-r--r-- | net/ipv4/ip_output.c | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index fc550e97daac..4c9532259a7f 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -97,12 +97,14 @@ EXPORT_SYMBOL(ip_send_check); static int __ip_local_out_sk(struct sock *sk, struct sk_buff *skb) { + struct net *net = dev_net(skb_dst(skb)->dev); struct iphdr *iph = ip_hdr(skb); iph->tot_len = htons(skb->len); ip_send_check(iph); - return nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, sk, skb, NULL, - skb_dst(skb)->dev, dst_output); + return nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, + net, sk, skb, NULL, skb_dst(skb)->dev, + dst_output); } int __ip_local_out(struct sk_buff *skb) @@ -322,7 +324,7 @@ int ip_mc_output(struct sock *sk, struct sk_buff *skb) struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); if (newskb) NF_HOOK(NFPROTO_IPV4, NF_INET_POST_ROUTING, - sk, newskb, NULL, newskb->dev, + net, sk, newskb, NULL, newskb->dev, dev_loopback_xmit); } @@ -337,12 +339,14 @@ int ip_mc_output(struct sock *sk, struct sk_buff *skb) if (rt->rt_flags&RTCF_BROADCAST) { struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); if (newskb) - NF_HOOK(NFPROTO_IPV4, NF_INET_POST_ROUTING, sk, newskb, - NULL, newskb->dev, dev_loopback_xmit); + NF_HOOK(NFPROTO_IPV4, NF_INET_POST_ROUTING, + net, sk, newskb, NULL, newskb->dev, + dev_loopback_xmit); } - return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, sk, skb, NULL, - skb->dev, ip_finish_output, + return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, + net, sk, skb, NULL, skb->dev, + ip_finish_output, !(IPCB(skb)->flags & IPSKB_REROUTED)); } @@ -356,8 +360,8 @@ int ip_output(struct sock *sk, struct sk_buff *skb) skb->dev = dev; skb->protocol = htons(ETH_P_IP); - return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, sk, skb, - NULL, dev, + return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, + net, sk, skb, NULL, dev, ip_finish_output, !(IPCB(skb)->flags & IPSKB_REROUTED)); } |