From 357b6cc5834eabc1be7c28a9faae7da061df097d Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Wed, 18 Mar 2020 10:33:22 +0100 Subject: netfilter: revert introduction of egress hook This reverts the following commits: 8537f78647c0 ("netfilter: Introduce egress hook") 5418d3881e1f ("netfilter: Generalize ingress hook") b030f194aed2 ("netfilter: Rename ingress hook include file") >From the discussion in [0], the author's main motivation to add a hook in fast path is for an out of tree kernel module, which is a red flag to begin with. Other mentioned potential use cases like NAT{64,46} is on future extensions w/o concrete code in the tree yet. Revert as suggested [1] given the weak justification to add more hooks to critical fast-path. [0] https://lore.kernel.org/netdev/cover.1583927267.git.lukas@wunner.de/ [1] https://lore.kernel.org/netdev/20200318.011152.72770718915606186.davem@davemloft.net/ Signed-off-by: Daniel Borkmann Cc: David Miller Cc: Pablo Neira Ayuso Cc: Alexei Starovoitov Nacked-by: Pablo Neira Ayuso Signed-off-by: David S. Miller --- include/linux/netdevice.h | 4 -- include/linux/netfilter_ingress.h | 58 ++++++++++++++++++++++ include/linux/netfilter_netdev.h | 102 -------------------------------------- 3 files changed, 58 insertions(+), 106 deletions(-) create mode 100644 include/linux/netfilter_ingress.h delete mode 100644 include/linux/netfilter_netdev.h (limited to 'include/linux') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 15f1e32b430c..654808bfad83 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1751,7 +1751,6 @@ enum netdev_priv_flags { * @xps_maps: XXX: need comments on this one * @miniq_egress: clsact qdisc specific data for * egress processing - * @nf_hooks_egress: netfilter hooks executed for egress packets * @qdisc_hash: qdisc hash table * @watchdog_timeo: Represents the timeout that is used by * the watchdog (see dev_watchdog()) @@ -2027,9 +2026,6 @@ struct net_device { #ifdef CONFIG_NET_CLS_ACT struct mini_Qdisc __rcu *miniq_egress; #endif -#ifdef CONFIG_NETFILTER_EGRESS - struct nf_hook_entries __rcu *nf_hooks_egress; -#endif #ifdef CONFIG_NET_SCHED DECLARE_HASHTABLE (qdisc_hash, 4); diff --git a/include/linux/netfilter_ingress.h b/include/linux/netfilter_ingress.h new file mode 100644 index 000000000000..a13774be2eb5 --- /dev/null +++ b/include/linux/netfilter_ingress.h @@ -0,0 +1,58 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _NETFILTER_INGRESS_H_ +#define _NETFILTER_INGRESS_H_ + +#include +#include + +#ifdef CONFIG_NETFILTER_INGRESS +static inline bool nf_hook_ingress_active(const struct sk_buff *skb) +{ +#ifdef CONFIG_JUMP_LABEL + if (!static_key_false(&nf_hooks_needed[NFPROTO_NETDEV][NF_NETDEV_INGRESS])) + return false; +#endif + return rcu_access_pointer(skb->dev->nf_hooks_ingress); +} + +/* caller must hold rcu_read_lock */ +static inline int nf_hook_ingress(struct sk_buff *skb) +{ + struct nf_hook_entries *e = rcu_dereference(skb->dev->nf_hooks_ingress); + struct nf_hook_state state; + int ret; + + /* Must recheck the ingress hook head, in the event it became NULL + * after the check in nf_hook_ingress_active evaluated to true. + */ + if (unlikely(!e)) + return 0; + + nf_hook_state_init(&state, NF_NETDEV_INGRESS, + NFPROTO_NETDEV, skb->dev, NULL, NULL, + dev_net(skb->dev), NULL); + ret = nf_hook_slow(skb, &state, e, 0); + if (ret == 0) + return -1; + + return ret; +} + +static inline void nf_hook_ingress_init(struct net_device *dev) +{ + RCU_INIT_POINTER(dev->nf_hooks_ingress, NULL); +} +#else /* CONFIG_NETFILTER_INGRESS */ +static inline int nf_hook_ingress_active(struct sk_buff *skb) +{ + return 0; +} + +static inline int nf_hook_ingress(struct sk_buff *skb) +{ + return 0; +} + +static inline void nf_hook_ingress_init(struct net_device *dev) {} +#endif /* CONFIG_NETFILTER_INGRESS */ +#endif /* _NETFILTER_INGRESS_H_ */ diff --git a/include/linux/netfilter_netdev.h b/include/linux/netfilter_netdev.h deleted file mode 100644 index 92d3611a782e..000000000000 --- a/include/linux/netfilter_netdev.h +++ /dev/null @@ -1,102 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifndef _NETFILTER_NETDEV_H_ -#define _NETFILTER_NETDEV_H_ - -#include -#include - -#ifdef CONFIG_NETFILTER -static __always_inline bool nf_hook_netdev_active(enum nf_dev_hooks hooknum, - struct nf_hook_entries __rcu *hooks) -{ -#ifdef CONFIG_JUMP_LABEL - if (!static_key_false(&nf_hooks_needed[NFPROTO_NETDEV][hooknum])) - return false; -#endif - return rcu_access_pointer(hooks); -} - -/* caller must hold rcu_read_lock */ -static __always_inline int nf_hook_netdev(struct sk_buff *skb, - enum nf_dev_hooks hooknum, - struct nf_hook_entries __rcu *hooks) -{ - struct nf_hook_entries *e = rcu_dereference(hooks); - struct nf_hook_state state; - int ret; - - /* Must recheck the hook head, in the event it became NULL - * after the check in nf_hook_netdev_active evaluated to true. - */ - if (unlikely(!e)) - return 0; - - nf_hook_state_init(&state, hooknum, - NFPROTO_NETDEV, skb->dev, NULL, NULL, - dev_net(skb->dev), NULL); - ret = nf_hook_slow(skb, &state, e, 0); - if (ret == 0) - return -1; - - return ret; -} -#endif /* CONFIG_NETFILTER */ - -static inline void nf_hook_netdev_init(struct net_device *dev) -{ -#ifdef CONFIG_NETFILTER_INGRESS - RCU_INIT_POINTER(dev->nf_hooks_ingress, NULL); -#endif -#ifdef CONFIG_NETFILTER_EGRESS - RCU_INIT_POINTER(dev->nf_hooks_egress, NULL); -#endif -} - -#ifdef CONFIG_NETFILTER_INGRESS -static inline bool nf_hook_ingress_active(const struct sk_buff *skb) -{ - return nf_hook_netdev_active(NF_NETDEV_INGRESS, - skb->dev->nf_hooks_ingress); -} - -static inline int nf_hook_ingress(struct sk_buff *skb) -{ - return nf_hook_netdev(skb, NF_NETDEV_INGRESS, - skb->dev->nf_hooks_ingress); -} -#else /* CONFIG_NETFILTER_INGRESS */ -static inline int nf_hook_ingress_active(struct sk_buff *skb) -{ - return 0; -} - -static inline int nf_hook_ingress(struct sk_buff *skb) -{ - return 0; -} -#endif /* CONFIG_NETFILTER_INGRESS */ - -#ifdef CONFIG_NETFILTER_EGRESS -static inline bool nf_hook_egress_active(const struct sk_buff *skb) -{ - return nf_hook_netdev_active(NF_NETDEV_EGRESS, - skb->dev->nf_hooks_egress); -} - -static inline int nf_hook_egress(struct sk_buff *skb) -{ - return nf_hook_netdev(skb, NF_NETDEV_EGRESS, - skb->dev->nf_hooks_egress); -} -#else /* CONFIG_NETFILTER_EGRESS */ -static inline int nf_hook_egress_active(struct sk_buff *skb) -{ - return 0; -} - -static inline int nf_hook_egress(struct sk_buff *skb) -{ - return 0; -} -#endif /* CONFIG_NETFILTER_EGRESS */ -#endif /* _NETFILTER_INGRESS_H_ */ -- cgit v1.2.3