From 29a26a56803855a79dbd028cd61abee56237d6e5 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 15 Sep 2015 20:04:16 -0500 Subject: 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" Signed-off-by: David S. Miller --- include/linux/netfilter.h | 27 ++++++++++++--------------- 1 file changed, 12 insertions(+), 15 deletions(-) (limited to 'include') diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h index 042148dc1e22..295f2650b5dc 100644 --- a/include/linux/netfilter.h +++ b/include/linux/netfilter.h @@ -190,12 +190,11 @@ static inline int nf_hook_thresh(u_int8_t pf, unsigned int hook, return 1; } -static inline int nf_hook(u_int8_t pf, unsigned int hook, struct sock *sk, - struct sk_buff *skb, struct net_device *indev, - struct net_device *outdev, +static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net, + struct sock *sk, struct sk_buff *skb, + struct net_device *indev, struct net_device *outdev, int (*okfn)(struct sock *, struct sk_buff *)) { - struct net *net = dev_net(indev ? indev : outdev); return nf_hook_thresh(pf, hook, net, sk, skb, indev, outdev, okfn, INT_MIN); } @@ -217,12 +216,11 @@ static inline int nf_hook(u_int8_t pf, unsigned int hook, struct sock *sk, */ static inline int -NF_HOOK_THRESH(uint8_t pf, unsigned int hook, struct sock *sk, +NF_HOOK_THRESH(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk, struct sk_buff *skb, struct net_device *in, struct net_device *out, int (*okfn)(struct sock *, struct sk_buff *), int thresh) { - struct net *net = dev_net(in ? in : out); int ret = nf_hook_thresh(pf, hook, net, sk, skb, in, out, okfn, thresh); if (ret == 1) ret = okfn(sk, skb); @@ -230,11 +228,10 @@ NF_HOOK_THRESH(uint8_t pf, unsigned int hook, struct sock *sk, } static inline int -NF_HOOK_COND(uint8_t pf, unsigned int hook, struct sock *sk, +NF_HOOK_COND(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk, struct sk_buff *skb, struct net_device *in, struct net_device *out, int (*okfn)(struct sock *, struct sk_buff *), bool cond) { - struct net *net = dev_net(in ? in : out); int ret; if (!cond || @@ -244,11 +241,11 @@ NF_HOOK_COND(uint8_t pf, unsigned int hook, struct sock *sk, } static inline int -NF_HOOK(uint8_t pf, unsigned int hook, struct sock *sk, struct sk_buff *skb, +NF_HOOK(uint8_t pf, unsigned int hook, struct net *net, struct sock *sk, struct sk_buff *skb, struct net_device *in, struct net_device *out, int (*okfn)(struct sock *, struct sk_buff *)) { - return NF_HOOK_THRESH(pf, hook, sk, skb, in, out, okfn, INT_MIN); + return NF_HOOK_THRESH(pf, hook, net, sk, skb, in, out, okfn, INT_MIN); } /* Call setsockopt() */ @@ -348,11 +345,11 @@ nf_nat_decode_session(struct sk_buff *skb, struct flowi *fl, u_int8_t family) } #else /* !CONFIG_NETFILTER */ -#define NF_HOOK(pf, hook, sk, skb, indev, outdev, okfn) (okfn)(sk, skb) -#define NF_HOOK_COND(pf, hook, sk, skb, indev, outdev, okfn, cond) (okfn)(sk, skb) -static inline int nf_hook(u_int8_t pf, unsigned int hook, struct sock *sk, - struct sk_buff *skb, struct net_device *indev, - struct net_device *outdev, +#define NF_HOOK(pf, hook, net, sk, skb, indev, outdev, okfn) (okfn)(sk, skb) +#define NF_HOOK_COND(pf, hook, net, sk, skb, indev, outdev, okfn, cond) (okfn)(sk, skb) +static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net, + struct sock *sk, struct sk_buff *skb, + struct net_device *indev, struct net_device *outdev, int (*okfn)(struct sock *, struct sk_buff *)) { return 1; -- cgit v1.2.3