Commit ac02bcf9 authored by Florian Westphal's avatar Florian Westphal Committed by Pablo Neira Ayuso
Browse files

netfilter: ipv6: avoid indirect calls for IPV6=y case 



indirect calls are only needed if ipv6 is a module.
Add helpers to abstract the v6ops indirections and use them instead.

fragment, reroute and route_input are kept as indirect calls.
The first two are not not used in hot path and route_input is only
used by bridge netfilter.

Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 96058728

include/linux/netfilter_ipv6.h

+51 −13
Original line number Diff line number Diff line
@@ -25,29 +25,24 @@ struct nf_queue_entry; 
 * if IPv6 is a module.

 */

struct nf_ipv6_ops {

#if IS_MODULE(CONFIG_IPV6)

	int (*chk_addr)(struct net *net, const struct in6_addr *addr,

			const struct net_device *dev, int strict);

	void (*route_input)(struct sk_buff *skb);

	int (*fragment)(struct net *net, struct sock *sk, struct sk_buff *skb,

			int (*output)(struct net *, struct sock *, struct sk_buff *));

	int (*route)(struct net *net, struct dst_entry **dst, struct flowi *fl,

		     bool strict);

	int (*reroute)(struct sk_buff *skb, const struct nf_queue_entry *entry);

#if IS_MODULE(CONFIG_IPV6)

	int (*route_me_harder)(struct net *net, struct sk_buff *skb);

	int (*dev_get_saddr)(struct net *net, const struct net_device *dev,

		       const struct in6_addr *daddr, unsigned int srcprefs,

		       struct in6_addr *saddr);

	int (*route)(struct net *net, struct dst_entry **dst, struct flowi *fl,

		     bool strict);

#endif

	void (*route_input)(struct sk_buff *skb);

	int (*fragment)(struct net *net, struct sock *sk, struct sk_buff *skb,

			int (*output)(struct net *, struct sock *, struct sk_buff *));

	int (*reroute)(struct sk_buff *skb, const struct nf_queue_entry *entry);

};



#ifdef CONFIG_NETFILTER

int ip6_route_me_harder(struct net *net, struct sk_buff *skb);

__sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,

			unsigned int dataoff, u_int8_t protocol);



int ipv6_netfilter_init(void);

void ipv6_netfilter_fini(void);

#include <net/addrconf.h>



extern const struct nf_ipv6_ops __rcu *nf_ipv6_ops;

static inline const struct nf_ipv6_ops *nf_get_ipv6_ops(void)
@@ -55,6 +50,49 @@ static inline const struct nf_ipv6_ops *nf_get_ipv6_ops(void) 
	return rcu_dereference(nf_ipv6_ops);

}



static inline int nf_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,

				   const struct net_device *dev, int strict)

{

#if IS_MODULE(CONFIG_IPV6)

	const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();



	if (!v6_ops)

		return 1;



	return v6_ops->chk_addr(net, addr, dev, strict);

#else

	return ipv6_chk_addr(net, addr, dev, strict);

#endif

}



int __nf_ip6_route(struct net *net, struct dst_entry **dst,

			       struct flowi *fl, bool strict);



static inline int nf_ip6_route(struct net *net, struct dst_entry **dst,

			       struct flowi *fl, bool strict)

{

#if IS_MODULE(CONFIG_IPV6)

	const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();



	if (v6ops)

		return v6ops->route(net, dst, fl, strict);



	return -EHOSTUNREACH;

#endif

#if IS_BUILTIN(CONFIG_IPV6)

	return __nf_ip6_route(net, dst, fl, strict);

#else

	return -EHOSTUNREACH;

#endif

}



int ip6_route_me_harder(struct net *net, struct sk_buff *skb);

__sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,

			unsigned int dataoff, u_int8_t protocol);



int ipv6_netfilter_init(void);

void ipv6_netfilter_fini(void);



#else /* CONFIG_NETFILTER */

static inline int ipv6_netfilter_init(void) { return 0; }

static inline void ipv6_netfilter_fini(void) { return; }

net/ipv6/netfilter.c

+8 −7
Original line number Diff line number Diff line
@@ -84,7 +84,7 @@ static int nf_ip6_reroute(struct sk_buff *skb, 
	return 0;

}



static int nf_ip6_route(struct net *net, struct dst_entry **dst,

int __nf_ip6_route(struct net *net, struct dst_entry **dst,

		   struct flowi *fl, bool strict)

{

	static const struct ipv6_pinfo fake_pinfo;
@@ -105,17 +105,18 @@ static int nf_ip6_route(struct net *net, struct dst_entry **dst, 
		*dst = result;

	return err;

}

EXPORT_SYMBOL_GPL(__nf_ip6_route);



static const struct nf_ipv6_ops ipv6ops = {

	.chk_addr		= ipv6_chk_addr,

	.route_input    	= ip6_route_input,

	.fragment		= ip6_fragment,

	.route			= nf_ip6_route,

	.reroute		= nf_ip6_reroute,

#if IS_MODULE(CONFIG_IPV6)

	.chk_addr		= ipv6_chk_addr,

	.route_me_harder	= ip6_route_me_harder,

	.dev_get_saddr		= ipv6_dev_get_saddr,

	.route			= __nf_ip6_route,

#endif

	.route_input		= ip6_route_input,

	.fragment		= ip6_fragment,

	.reroute		= nf_ip6_reroute,

};



int __init ipv6_netfilter_init(void)

net/ipv6/netfilter/nft_fib_ipv6.c

+2 −7
Original line number Diff line number Diff line
@@ -59,7 +59,6 @@ static u32 __nft_fib6_eval_type(const struct nft_fib *priv, 
				struct ipv6hdr *iph)

{

	const struct net_device *dev = NULL;

	const struct nf_ipv6_ops *v6ops;

	int route_err, addrtype;

	struct rt6_info *rt;

	struct flowi6 fl6 = {
@@ -68,10 +67,6 @@ static u32 __nft_fib6_eval_type(const struct nft_fib *priv, 
	};

	u32 ret = 0;



	v6ops = nf_get_ipv6_ops();

	if (!v6ops)

		return RTN_UNREACHABLE;



	if (priv->flags & NFTA_FIB_F_IIF)

		dev = nft_in(pkt);

	else if (priv->flags & NFTA_FIB_F_OIF)
@@ -79,10 +74,10 @@ static u32 __nft_fib6_eval_type(const struct nft_fib *priv, 


	nft_fib6_flowi_init(&fl6, priv, pkt, dev, iph);



	if (dev && v6ops->chk_addr(nft_net(pkt), &fl6.daddr, dev, true))

	if (dev && nf_ipv6_chk_addr(nft_net(pkt), &fl6.daddr, dev, true))

		ret = RTN_LOCAL;



	route_err = v6ops->route(nft_net(pkt), (struct dst_entry **)&rt,

	route_err = nf_ip6_route(nft_net(pkt), (struct dst_entry **)&rt,

				 flowi6_to_flowi(&fl6), false);

	if (route_err)

		goto err;

net/netfilter/utils.c

+2 −4
Original line number Diff line number Diff line
@@ -162,7 +162,7 @@ EXPORT_SYMBOL_GPL(nf_checksum_partial); 
int nf_route(struct net *net, struct dst_entry **dst, struct flowi *fl,

	     bool strict, unsigned short family)

{

	const struct nf_ipv6_ops *v6ops;

	const struct nf_ipv6_ops *v6ops __maybe_unused;

	int ret = 0;



	switch (family) {
@@ -170,9 +170,7 @@ int nf_route(struct net *net, struct dst_entry **dst, struct flowi *fl, 
		ret = nf_ip_route(net, dst, fl, strict);

		break;

	case AF_INET6:

		v6ops = rcu_dereference(nf_ipv6_ops);

		if (v6ops)

			ret = v6ops->route(net, dst, fl, strict);

		ret = nf_ip6_route(net, dst, fl, strict);

		break;

	}

net/netfilter/xt_addrtype.c

+5 −11
Original line number Diff line number Diff line
@@ -36,7 +36,6 @@ MODULE_ALIAS("ip6t_addrtype"); 
static u32 match_lookup_rt6(struct net *net, const struct net_device *dev,

			    const struct in6_addr *addr, u16 mask)

{

	const struct nf_ipv6_ops *v6ops;

	struct flowi6 flow;

	struct rt6_info *rt;

	u32 ret = 0;
@@ -47,18 +46,13 @@ static u32 match_lookup_rt6(struct net *net, const struct net_device *dev, 
	if (dev)

		flow.flowi6_oif = dev->ifindex;



	v6ops = nf_get_ipv6_ops();

	if (v6ops) {

	if (dev && (mask & XT_ADDRTYPE_LOCAL)) {

			if (v6ops->chk_addr(net, addr, dev, true))

		if (nf_ipv6_chk_addr(net, addr, dev, true))

			ret = XT_ADDRTYPE_LOCAL;

	}

		route_err = v6ops->route(net, (struct dst_entry **)&rt,

					 flowi6_to_flowi(&flow), false);

	} else {

		route_err = 1;

	}



	route_err = nf_ip6_route(net, (struct dst_entry **)&rt,

				 flowi6_to_flowi(&flow), false);

	if (route_err)

		return XT_ADDRTYPE_UNREACHABLE;

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