route.c 73.2 KB
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/*
 *	Linux INET6 implementation
 *	FIB front-end.
 *
 *	Authors:
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 *	Pedro Roque		<roque@di.fc.ul.pt>
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 *
 *	This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

/*	Changes:
 *
 *	YOSHIFUJI Hideaki @USAGI
 *		reworked default router selection.
 *		- respect outgoing interface
 *		- select from (probably) reachable routers (i.e.
 *		routers in REACHABLE, STALE, DELAY or PROBE states).
 *		- always select the same router if it is (probably)
 *		reachable.  otherwise, round-robin the list.
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 *	Ville Nuorvala
 *		Fixed routing subtrees.
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 */

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#define pr_fmt(fmt) "IPv6: " fmt

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#include <linux/capability.h>
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#include <linux/errno.h>
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#include <linux/export.h>
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#include <linux/types.h>
#include <linux/times.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/route.h>
#include <linux/netdevice.h>
#include <linux/in6.h>
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#include <linux/mroute6.h>
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#include <linux/init.h>
#include <linux/if_arp.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
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#include <linux/nsproxy.h>
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#include <linux/slab.h>
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#include <net/net_namespace.h>
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#include <net/snmp.h>
#include <net/ipv6.h>
#include <net/ip6_fib.h>
#include <net/ip6_route.h>
#include <net/ndisc.h>
#include <net/addrconf.h>
#include <net/tcp.h>
#include <linux/rtnetlink.h>
#include <net/dst.h>
#include <net/xfrm.h>
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#include <net/netevent.h>
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#include <net/netlink.h>
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#include <asm/uaccess.h>

#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
#endif

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static struct rt6_info *ip6_rt_copy(struct rt6_info *ort,
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				    const struct in6_addr *dest);
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static struct dst_entry	*ip6_dst_check(struct dst_entry *dst, u32 cookie);
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static unsigned int	 ip6_default_advmss(const struct dst_entry *dst);
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static unsigned int	 ip6_mtu(const struct dst_entry *dst);
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static struct dst_entry *ip6_negative_advice(struct dst_entry *);
static void		ip6_dst_destroy(struct dst_entry *);
static void		ip6_dst_ifdown(struct dst_entry *,
				       struct net_device *dev, int how);
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static int		 ip6_dst_gc(struct dst_ops *ops);
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static int		ip6_pkt_discard(struct sk_buff *skb);
static int		ip6_pkt_discard_out(struct sk_buff *skb);
static void		ip6_link_failure(struct sk_buff *skb);
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static void		ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
					   struct sk_buff *skb, u32 mtu);
static void		rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
					struct sk_buff *skb);
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#ifdef CONFIG_IPV6_ROUTE_INFO
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static struct rt6_info *rt6_add_route_info(struct net *net,
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					   const struct in6_addr *prefix, int prefixlen,
					   const struct in6_addr *gwaddr, int ifindex,
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					   unsigned int pref);
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static struct rt6_info *rt6_get_route_info(struct net *net,
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					   const struct in6_addr *prefix, int prefixlen,
					   const struct in6_addr *gwaddr, int ifindex);
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#endif

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static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
{
	struct rt6_info *rt = (struct rt6_info *) dst;
	struct inet_peer *peer;
	u32 *p = NULL;

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	if (!(rt->dst.flags & DST_HOST))
		return NULL;

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	peer = rt6_get_peer_create(rt);
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	if (peer) {
		u32 *old_p = __DST_METRICS_PTR(old);
		unsigned long prev, new;

		p = peer->metrics;
		if (inet_metrics_new(peer))
			memcpy(p, old_p, sizeof(u32) * RTAX_MAX);

		new = (unsigned long) p;
		prev = cmpxchg(&dst->_metrics, old, new);

		if (prev != old) {
			p = __DST_METRICS_PTR(prev);
			if (prev & DST_METRICS_READ_ONLY)
				p = NULL;
		}
	}
	return p;
}

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static inline const void *choose_neigh_daddr(struct rt6_info *rt,
					     struct sk_buff *skb,
					     const void *daddr)
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{
	struct in6_addr *p = &rt->rt6i_gateway;

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	if (!ipv6_addr_any(p))
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		return (const void *) p;
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	else if (skb)
		return &ipv6_hdr(skb)->daddr;
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	return daddr;
}

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static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
					  struct sk_buff *skb,
					  const void *daddr)
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{
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	struct rt6_info *rt = (struct rt6_info *) dst;
	struct neighbour *n;

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	daddr = choose_neigh_daddr(rt, skb, daddr);
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	n = __ipv6_neigh_lookup(&nd_tbl, dst->dev, daddr);
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	if (n)
		return n;
	return neigh_create(&nd_tbl, daddr, dst->dev);
}

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static int rt6_bind_neighbour(struct rt6_info *rt, struct net_device *dev)
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{
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	struct neighbour *n = __ipv6_neigh_lookup(&nd_tbl, dev, &rt->rt6i_gateway);
	if (!n) {
		n = neigh_create(&nd_tbl, &rt->rt6i_gateway, dev);
		if (IS_ERR(n))
			return PTR_ERR(n);
	}
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	rt->n = n;
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	return 0;
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}

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static struct dst_ops ip6_dst_ops_template = {
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	.family			=	AF_INET6,
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	.protocol		=	cpu_to_be16(ETH_P_IPV6),
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	.gc			=	ip6_dst_gc,
	.gc_thresh		=	1024,
	.check			=	ip6_dst_check,
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	.default_advmss		=	ip6_default_advmss,
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	.mtu			=	ip6_mtu,
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	.cow_metrics		=	ipv6_cow_metrics,
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	.destroy		=	ip6_dst_destroy,
	.ifdown			=	ip6_dst_ifdown,
	.negative_advice	=	ip6_negative_advice,
	.link_failure		=	ip6_link_failure,
	.update_pmtu		=	ip6_rt_update_pmtu,
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	.redirect		=	rt6_do_redirect,
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	.local_out		=	__ip6_local_out,
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	.neigh_lookup		=	ip6_neigh_lookup,
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};

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static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
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{
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	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);

	return mtu ? : dst->dev->mtu;
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}

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static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
					 struct sk_buff *skb, u32 mtu)
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{
}

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static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
				      struct sk_buff *skb)
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{
}

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static u32 *ip6_rt_blackhole_cow_metrics(struct dst_entry *dst,
					 unsigned long old)
{
	return NULL;
}

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static struct dst_ops ip6_dst_blackhole_ops = {
	.family			=	AF_INET6,
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	.protocol		=	cpu_to_be16(ETH_P_IPV6),
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	.destroy		=	ip6_dst_destroy,
	.check			=	ip6_dst_check,
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	.mtu			=	ip6_blackhole_mtu,
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	.default_advmss		=	ip6_default_advmss,
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	.update_pmtu		=	ip6_rt_blackhole_update_pmtu,
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	.redirect		=	ip6_rt_blackhole_redirect,
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	.cow_metrics		=	ip6_rt_blackhole_cow_metrics,
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	.neigh_lookup		=	ip6_neigh_lookup,
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};

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static const u32 ip6_template_metrics[RTAX_MAX] = {
	[RTAX_HOPLIMIT - 1] = 255,
};

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static struct rt6_info ip6_null_entry_template = {
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	.dst = {
		.__refcnt	= ATOMIC_INIT(1),
		.__use		= 1,
		.obsolete	= -1,
		.error		= -ENETUNREACH,
		.input		= ip6_pkt_discard,
		.output		= ip6_pkt_discard_out,
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	},
	.rt6i_flags	= (RTF_REJECT | RTF_NONEXTHOP),
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	.rt6i_protocol  = RTPROT_KERNEL,
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	.rt6i_metric	= ~(u32) 0,
	.rt6i_ref	= ATOMIC_INIT(1),
};

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#ifdef CONFIG_IPV6_MULTIPLE_TABLES

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static int ip6_pkt_prohibit(struct sk_buff *skb);
static int ip6_pkt_prohibit_out(struct sk_buff *skb);

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static struct rt6_info ip6_prohibit_entry_template = {
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	.dst = {
		.__refcnt	= ATOMIC_INIT(1),
		.__use		= 1,
		.obsolete	= -1,
		.error		= -EACCES,
		.input		= ip6_pkt_prohibit,
		.output		= ip6_pkt_prohibit_out,
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	},
	.rt6i_flags	= (RTF_REJECT | RTF_NONEXTHOP),
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	.rt6i_protocol  = RTPROT_KERNEL,
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	.rt6i_metric	= ~(u32) 0,
	.rt6i_ref	= ATOMIC_INIT(1),
};

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static struct rt6_info ip6_blk_hole_entry_template = {
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	.dst = {
		.__refcnt	= ATOMIC_INIT(1),
		.__use		= 1,
		.obsolete	= -1,
		.error		= -EINVAL,
		.input		= dst_discard,
		.output		= dst_discard,
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	},
	.rt6i_flags	= (RTF_REJECT | RTF_NONEXTHOP),
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	.rt6i_protocol  = RTPROT_KERNEL,
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	.rt6i_metric	= ~(u32) 0,
	.rt6i_ref	= ATOMIC_INIT(1),
};

#endif

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/* allocate dst with ip6_dst_ops */
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static inline struct rt6_info *ip6_dst_alloc(struct net *net,
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					     struct net_device *dev,
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					     int flags,
					     struct fib6_table *table)
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{
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	struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
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					0, DST_OBSOLETE_FORCE_CHK, flags);
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	if (rt) {
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		struct dst_entry *dst = &rt->dst;

		memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
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		rt6_init_peer(rt, table ? &table->tb6_peers : net->ipv6.peers);
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		rt->rt6i_genid = rt_genid(net);
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	}
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	return rt;
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}

static void ip6_dst_destroy(struct dst_entry *dst)
{
	struct rt6_info *rt = (struct rt6_info *)dst;
	struct inet6_dev *idev = rt->rt6i_idev;

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	if (rt->n)
		neigh_release(rt->n);

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	if (!(rt->dst.flags & DST_HOST))
		dst_destroy_metrics_generic(dst);

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	if (idev) {
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		rt->rt6i_idev = NULL;
		in6_dev_put(idev);
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	}
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	if (!(rt->rt6i_flags & RTF_EXPIRES) && dst->from)
		dst_release(dst->from);

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	if (rt6_has_peer(rt)) {
		struct inet_peer *peer = rt6_peer_ptr(rt);
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		inet_putpeer(peer);
	}
}

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static atomic_t __rt6_peer_genid = ATOMIC_INIT(0);

static u32 rt6_peer_genid(void)
{
	return atomic_read(&__rt6_peer_genid);
}

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void rt6_bind_peer(struct rt6_info *rt, int create)
{
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	struct inet_peer_base *base;
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	struct inet_peer *peer;

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	base = inetpeer_base_ptr(rt->_rt6i_peer);
	if (!base)
		return;

	peer = inet_getpeer_v6(base, &rt->rt6i_dst.addr, create);
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	if (peer) {
		if (!rt6_set_peer(rt, peer))
			inet_putpeer(peer);
		else
			rt->rt6i_peer_genid = rt6_peer_genid();
	}
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}

static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
			   int how)
{
	struct rt6_info *rt = (struct rt6_info *)dst;
	struct inet6_dev *idev = rt->rt6i_idev;
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	struct net_device *loopback_dev =
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		dev_net(dev)->loopback_dev;
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	if (dev != loopback_dev) {
		if (idev && idev->dev == dev) {
			struct inet6_dev *loopback_idev =
				in6_dev_get(loopback_dev);
			if (loopback_idev) {
				rt->rt6i_idev = loopback_idev;
				in6_dev_put(idev);
			}
		}
		if (rt->n && rt->n->dev == dev) {
			rt->n->dev = loopback_dev;
			dev_hold(loopback_dev);
			dev_put(dev);
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		}
	}
}

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static bool rt6_check_expired(const struct rt6_info *rt)
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{
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	struct rt6_info *ort = NULL;

	if (rt->rt6i_flags & RTF_EXPIRES) {
		if (time_after(jiffies, rt->dst.expires))
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			return true;
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	} else if (rt->dst.from) {
		ort = (struct rt6_info *) rt->dst.from;
		return (ort->rt6i_flags & RTF_EXPIRES) &&
			time_after(jiffies, ort->dst.expires);
	}
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	return false;
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}

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static bool rt6_need_strict(const struct in6_addr *daddr)
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{
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	return ipv6_addr_type(daddr) &
		(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
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}

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/*
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 *	Route lookup. Any table->tb6_lock is implied.
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 */

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static inline struct rt6_info *rt6_device_match(struct net *net,
						    struct rt6_info *rt,
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						    const struct in6_addr *saddr,
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						    int oif,
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						    int flags)
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{
	struct rt6_info *local = NULL;
	struct rt6_info *sprt;

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	if (!oif && ipv6_addr_any(saddr))
		goto out;

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	for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
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		struct net_device *dev = sprt->dst.dev;
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		if (oif) {
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			if (dev->ifindex == oif)
				return sprt;
			if (dev->flags & IFF_LOOPBACK) {
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				if (!sprt->rt6i_idev ||
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				    sprt->rt6i_idev->dev->ifindex != oif) {
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					if (flags & RT6_LOOKUP_F_IFACE && oif)
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						continue;
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					if (local && (!oif ||
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						      local->rt6i_idev->dev->ifindex == oif))
						continue;
				}
				local = sprt;
			}
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		} else {
			if (ipv6_chk_addr(net, saddr, dev,
					  flags & RT6_LOOKUP_F_IFACE))
				return sprt;
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		}
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	}
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	if (oif) {
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		if (local)
			return local;

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		if (flags & RT6_LOOKUP_F_IFACE)
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			return net->ipv6.ip6_null_entry;
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	}
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out:
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	return rt;
}

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#ifdef CONFIG_IPV6_ROUTER_PREF
static void rt6_probe(struct rt6_info *rt)
{
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	struct neighbour *neigh;
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	/*
	 * Okay, this does not seem to be appropriate
	 * for now, however, we need to check if it
	 * is really so; aka Router Reachability Probing.
	 *
	 * Router Reachability Probe MUST be rate-limited
	 * to no more than one per minute.
	 */
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	rcu_read_lock();
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	neigh = rt ? rt->n : NULL;
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	if (!neigh || (neigh->nud_state & NUD_VALID))
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		goto out;
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	read_lock_bh(&neigh->lock);
	if (!(neigh->nud_state & NUD_VALID) &&
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	    time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
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		struct in6_addr mcaddr;
		struct in6_addr *target;

		neigh->updated = jiffies;
		read_unlock_bh(&neigh->lock);

		target = (struct in6_addr *)&neigh->primary_key;
		addrconf_addr_solict_mult(target, &mcaddr);
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		ndisc_send_ns(rt->dst.dev, NULL, target, &mcaddr, NULL);
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	} else {
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		read_unlock_bh(&neigh->lock);
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	}
out:
	rcu_read_unlock();
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}
#else
static inline void rt6_probe(struct rt6_info *rt)
{
}
#endif

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/*
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 * Default Router Selection (RFC 2461 6.3.6)
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 */
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static inline int rt6_check_dev(struct rt6_info *rt, int oif)
487
{
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	struct net_device *dev = rt->dst.dev;
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	if (!oif || dev->ifindex == oif)
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		return 2;
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	if ((dev->flags & IFF_LOOPBACK) &&
	    rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
		return 1;
	return 0;
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}
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static inline int rt6_check_neigh(struct rt6_info *rt)
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{
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	struct neighbour *neigh;
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	int m;
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	rcu_read_lock();
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	neigh = rt->n;
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	if (rt->rt6i_flags & RTF_NONEXTHOP ||
	    !(rt->rt6i_flags & RTF_GATEWAY))
		m = 1;
	else if (neigh) {
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		read_lock_bh(&neigh->lock);
		if (neigh->nud_state & NUD_VALID)
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			m = 2;
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#ifdef CONFIG_IPV6_ROUTER_PREF
		else if (neigh->nud_state & NUD_FAILED)
			m = 0;
#endif
		else
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			m = 1;
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		read_unlock_bh(&neigh->lock);
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	} else
		m = 0;
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	rcu_read_unlock();
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	return m;
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}

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static int rt6_score_route(struct rt6_info *rt, int oif,
			   int strict)
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{
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	int m, n;
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	m = rt6_check_dev(rt, oif);
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	if (!m && (strict & RT6_LOOKUP_F_IFACE))
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		return -1;
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#ifdef CONFIG_IPV6_ROUTER_PREF
	m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
#endif
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	n = rt6_check_neigh(rt);
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	if (!n && (strict & RT6_LOOKUP_F_REACHABLE))
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		return -1;
	return m;
}

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static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
				   int *mpri, struct rt6_info *match)
543
{
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	int m;

	if (rt6_check_expired(rt))
		goto out;

	m = rt6_score_route(rt, oif, strict);
	if (m < 0)
		goto out;

	if (m > *mpri) {
		if (strict & RT6_LOOKUP_F_REACHABLE)
			rt6_probe(match);
		*mpri = m;
		match = rt;
	} else if (strict & RT6_LOOKUP_F_REACHABLE) {
		rt6_probe(rt);
	}

out:
	return match;
}

static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
				     struct rt6_info *rr_head,
				     u32 metric, int oif, int strict)
{
	struct rt6_info *rt, *match;
571
	int mpri = -1;
L
Linus Torvalds 已提交
572

573 574
	match = NULL;
	for (rt = rr_head; rt && rt->rt6i_metric == metric;
575
	     rt = rt->dst.rt6_next)
576 577
		match = find_match(rt, oif, strict, &mpri, match);
	for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
578
	     rt = rt->dst.rt6_next)
579
		match = find_match(rt, oif, strict, &mpri, match);
L
Linus Torvalds 已提交
580

581 582
	return match;
}
L
Linus Torvalds 已提交
583

584 585 586
static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
{
	struct rt6_info *match, *rt0;
587
	struct net *net;
L
Linus Torvalds 已提交
588

589 590 591
	rt0 = fn->rr_ptr;
	if (!rt0)
		fn->rr_ptr = rt0 = fn->leaf;
L
Linus Torvalds 已提交
592

593
	match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict);
L
Linus Torvalds 已提交
594

595
	if (!match &&
596
	    (strict & RT6_LOOKUP_F_REACHABLE)) {
597
		struct rt6_info *next = rt0->dst.rt6_next;
598

599
		/* no entries matched; do round-robin */
600 601 602 603 604
		if (!next || next->rt6i_metric != rt0->rt6i_metric)
			next = fn->leaf;

		if (next != rt0)
			fn->rr_ptr = next;
L
Linus Torvalds 已提交
605 606
	}

607
	net = dev_net(rt0->dst.dev);
E
Eric Dumazet 已提交
608
	return match ? match : net->ipv6.ip6_null_entry;
L
Linus Torvalds 已提交
609 610
}

611 612
#ifdef CONFIG_IPV6_ROUTE_INFO
int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
613
		  const struct in6_addr *gwaddr)
614
{
615
	struct net *net = dev_net(dev);
616 617 618
	struct route_info *rinfo = (struct route_info *) opt;
	struct in6_addr prefix_buf, *prefix;
	unsigned int pref;
619
	unsigned long lifetime;
620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642
	struct rt6_info *rt;

	if (len < sizeof(struct route_info)) {
		return -EINVAL;
	}

	/* Sanity check for prefix_len and length */
	if (rinfo->length > 3) {
		return -EINVAL;
	} else if (rinfo->prefix_len > 128) {
		return -EINVAL;
	} else if (rinfo->prefix_len > 64) {
		if (rinfo->length < 2) {
			return -EINVAL;
		}
	} else if (rinfo->prefix_len > 0) {
		if (rinfo->length < 1) {
			return -EINVAL;
		}
	}

	pref = rinfo->route_pref;
	if (pref == ICMPV6_ROUTER_PREF_INVALID)
643
		return -EINVAL;
644

645
	lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
646 647 648 649 650 651 652 653 654 655 656

	if (rinfo->length == 3)
		prefix = (struct in6_addr *)rinfo->prefix;
	else {
		/* this function is safe */
		ipv6_addr_prefix(&prefix_buf,
				 (struct in6_addr *)rinfo->prefix,
				 rinfo->prefix_len);
		prefix = &prefix_buf;
	}

657 658
	rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, gwaddr,
				dev->ifindex);
659 660

	if (rt && !lifetime) {
661
		ip6_del_rt(rt);
662 663 664 665
		rt = NULL;
	}

	if (!rt && lifetime)
666
		rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
667 668 669 670 671 672
					pref);
	else if (rt)
		rt->rt6i_flags = RTF_ROUTEINFO |
				 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);

	if (rt) {
673 674 675 676 677
		if (!addrconf_finite_timeout(lifetime))
			rt6_clean_expires(rt);
		else
			rt6_set_expires(rt, jiffies + HZ * lifetime);

678
		dst_release(&rt->dst);
679 680 681 682 683
	}
	return 0;
}
#endif

684
#define BACKTRACK(__net, saddr)			\
685
do { \
686
	if (rt == __net->ipv6.ip6_null_entry) {	\
687
		struct fib6_node *pn; \
V
Ville Nuorvala 已提交
688
		while (1) { \
689 690 691 692
			if (fn->fn_flags & RTN_TL_ROOT) \
				goto out; \
			pn = fn->parent; \
			if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
693
				fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
694 695 696 697
			else \
				fn = pn; \
			if (fn->fn_flags & RTN_RTINFO) \
				goto restart; \
T
Thomas Graf 已提交
698 699
		} \
	} \
700
} while (0)
T
Thomas Graf 已提交
701

702 703
static struct rt6_info *ip6_pol_route_lookup(struct net *net,
					     struct fib6_table *table,
704
					     struct flowi6 *fl6, int flags)
L
Linus Torvalds 已提交
705 706 707 708
{
	struct fib6_node *fn;
	struct rt6_info *rt;

T
Thomas Graf 已提交
709
	read_lock_bh(&table->tb6_lock);
710
	fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
T
Thomas Graf 已提交
711 712
restart:
	rt = fn->leaf;
713 714
	rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
	BACKTRACK(net, &fl6->saddr);
T
Thomas Graf 已提交
715
out:
716
	dst_use(&rt->dst, jiffies);
T
Thomas Graf 已提交
717 718 719 720 721
	read_unlock_bh(&table->tb6_lock);
	return rt;

}

F
Florian Westphal 已提交
722 723 724 725 726 727 728
struct dst_entry * ip6_route_lookup(struct net *net, struct flowi6 *fl6,
				    int flags)
{
	return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
}
EXPORT_SYMBOL_GPL(ip6_route_lookup);

729 730
struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
			    const struct in6_addr *saddr, int oif, int strict)
T
Thomas Graf 已提交
731
{
732 733 734
	struct flowi6 fl6 = {
		.flowi6_oif = oif,
		.daddr = *daddr,
T
Thomas Graf 已提交
735 736
	};
	struct dst_entry *dst;
737
	int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
T
Thomas Graf 已提交
738

739
	if (saddr) {
740
		memcpy(&fl6.saddr, saddr, sizeof(*saddr));
741 742 743
		flags |= RT6_LOOKUP_F_HAS_SADDR;
	}

744
	dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
T
Thomas Graf 已提交
745 746 747 748 749
	if (dst->error == 0)
		return (struct rt6_info *) dst;

	dst_release(dst);

L
Linus Torvalds 已提交
750 751 752
	return NULL;
}

753 754
EXPORT_SYMBOL(rt6_lookup);

T
Thomas Graf 已提交
755
/* ip6_ins_rt is called with FREE table->tb6_lock.
L
Linus Torvalds 已提交
756 757 758 759 760
   It takes new route entry, the addition fails by any reason the
   route is freed. In any case, if caller does not hold it, it may
   be destroyed.
 */

761
static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
L
Linus Torvalds 已提交
762 763
{
	int err;
T
Thomas Graf 已提交
764
	struct fib6_table *table;
L
Linus Torvalds 已提交
765

T
Thomas Graf 已提交
766 767
	table = rt->rt6i_table;
	write_lock_bh(&table->tb6_lock);
768
	err = fib6_add(&table->tb6_root, rt, info);
T
Thomas Graf 已提交
769
	write_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
770 771 772 773

	return err;
}

774 775
int ip6_ins_rt(struct rt6_info *rt)
{
776
	struct nl_info info = {
777
		.nl_net = dev_net(rt->dst.dev),
778
	};
779
	return __ip6_ins_rt(rt, &info);
780 781
}

782
static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort,
E
Eric Dumazet 已提交
783
				      const struct in6_addr *daddr,
784
				      const struct in6_addr *saddr)
L
Linus Torvalds 已提交
785 786 787 788 789 790 791
{
	struct rt6_info *rt;

	/*
	 *	Clone the route.
	 */

E
Eric Dumazet 已提交
792
	rt = ip6_rt_copy(ort, daddr);
L
Linus Torvalds 已提交
793 794

	if (rt) {
795 796
		int attempts = !in_softirq();

797
		if (!(rt->rt6i_flags & RTF_GATEWAY)) {
798
			if (ort->rt6i_dst.plen != 128 &&
E
Eric Dumazet 已提交
799
			    ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
800
				rt->rt6i_flags |= RTF_ANYCAST;
A
Alexey Dobriyan 已提交
801
			rt->rt6i_gateway = *daddr;
802
		}
L
Linus Torvalds 已提交
803 804 805 806 807

		rt->rt6i_flags |= RTF_CACHE;

#ifdef CONFIG_IPV6_SUBTREES
		if (rt->rt6i_src.plen && saddr) {
A
Alexey Dobriyan 已提交
808
			rt->rt6i_src.addr = *saddr;
L
Linus Torvalds 已提交
809 810 811 812
			rt->rt6i_src.plen = 128;
		}
#endif

813
	retry:
814
		if (rt6_bind_neighbour(rt, rt->dst.dev)) {
815
			struct net *net = dev_net(rt->dst.dev);
816 817 818 819 820 821 822 823 824
			int saved_rt_min_interval =
				net->ipv6.sysctl.ip6_rt_gc_min_interval;
			int saved_rt_elasticity =
				net->ipv6.sysctl.ip6_rt_gc_elasticity;

			if (attempts-- > 0) {
				net->ipv6.sysctl.ip6_rt_gc_elasticity = 1;
				net->ipv6.sysctl.ip6_rt_gc_min_interval = 0;

825
				ip6_dst_gc(&net->ipv6.ip6_dst_ops);
826 827 828 829 830 831 832 833

				net->ipv6.sysctl.ip6_rt_gc_elasticity =
					saved_rt_elasticity;
				net->ipv6.sysctl.ip6_rt_gc_min_interval =
					saved_rt_min_interval;
				goto retry;
			}

834
			net_warn_ratelimited("Neighbour table overflow\n");
835
			dst_free(&rt->dst);
836 837
			return NULL;
		}
838
	}
L
Linus Torvalds 已提交
839

840 841
	return rt;
}
L
Linus Torvalds 已提交
842

E
Eric Dumazet 已提交
843 844
static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort,
					const struct in6_addr *daddr)
845
{
E
Eric Dumazet 已提交
846 847
	struct rt6_info *rt = ip6_rt_copy(ort, daddr);

848 849
	if (rt) {
		rt->rt6i_flags |= RTF_CACHE;
850
		rt->n = neigh_clone(ort->n);
851 852 853 854
	}
	return rt;
}

855
static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
856
				      struct flowi6 *fl6, int flags)
L
Linus Torvalds 已提交
857 858
{
	struct fib6_node *fn;
859
	struct rt6_info *rt, *nrt;
T
Thomas Graf 已提交
860
	int strict = 0;
L
Linus Torvalds 已提交
861
	int attempts = 3;
862
	int err;
863
	int reachable = net->ipv6.devconf_all->forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
L
Linus Torvalds 已提交
864

865
	strict |= flags & RT6_LOOKUP_F_IFACE;
L
Linus Torvalds 已提交
866 867

relookup:
T
Thomas Graf 已提交
868
	read_lock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
869

870
restart_2:
871
	fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
L
Linus Torvalds 已提交
872 873

restart:
874
	rt = rt6_select(fn, oif, strict | reachable);
875

876
	BACKTRACK(net, &fl6->saddr);
877
	if (rt == net->ipv6.ip6_null_entry ||
878
	    rt->rt6i_flags & RTF_CACHE)
879
		goto out;
L
Linus Torvalds 已提交
880

881
	dst_hold(&rt->dst);
T
Thomas Graf 已提交
882
	read_unlock_bh(&table->tb6_lock);
883

884
	if (!rt->n && !(rt->rt6i_flags & RTF_NONEXTHOP))
885
		nrt = rt6_alloc_cow(rt, &fl6->daddr, &fl6->saddr);
886
	else if (!(rt->dst.flags & DST_HOST))
887
		nrt = rt6_alloc_clone(rt, &fl6->daddr);
888 889
	else
		goto out2;
890

891
	dst_release(&rt->dst);
892
	rt = nrt ? : net->ipv6.ip6_null_entry;
L
Linus Torvalds 已提交
893

894
	dst_hold(&rt->dst);
895
	if (nrt) {
896
		err = ip6_ins_rt(nrt);
897
		if (!err)
L
Linus Torvalds 已提交
898 899 900
			goto out2;
	}

901 902 903 904
	if (--attempts <= 0)
		goto out2;

	/*
T
Thomas Graf 已提交
905
	 * Race condition! In the gap, when table->tb6_lock was
906 907
	 * released someone could insert this route.  Relookup.
	 */
908
	dst_release(&rt->dst);
909 910 911
	goto relookup;

out:
912 913 914 915
	if (reachable) {
		reachable = 0;
		goto restart_2;
	}
916
	dst_hold(&rt->dst);
T
Thomas Graf 已提交
917
	read_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
918
out2:
919 920
	rt->dst.lastuse = jiffies;
	rt->dst.__use++;
T
Thomas Graf 已提交
921 922

	return rt;
L
Linus Torvalds 已提交
923 924
}

925
static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
926
					    struct flowi6 *fl6, int flags)
927
{
928
	return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
929 930
}

931 932 933 934 935 936 937 938 939 940
static struct dst_entry *ip6_route_input_lookup(struct net *net,
						struct net_device *dev,
						struct flowi6 *fl6, int flags)
{
	if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
		flags |= RT6_LOOKUP_F_IFACE;

	return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
}

T
Thomas Graf 已提交
941 942
void ip6_route_input(struct sk_buff *skb)
{
943
	const struct ipv6hdr *iph = ipv6_hdr(skb);
944
	struct net *net = dev_net(skb->dev);
945
	int flags = RT6_LOOKUP_F_HAS_SADDR;
946 947 948 949
	struct flowi6 fl6 = {
		.flowi6_iif = skb->dev->ifindex,
		.daddr = iph->daddr,
		.saddr = iph->saddr,
950
		.flowlabel = (* (__be32 *) iph) & IPV6_FLOWINFO_MASK,
951 952
		.flowi6_mark = skb->mark,
		.flowi6_proto = iph->nexthdr,
T
Thomas Graf 已提交
953
	};
954

955
	skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
T
Thomas Graf 已提交
956 957
}

958
static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
959
					     struct flowi6 *fl6, int flags)
L
Linus Torvalds 已提交
960
{
961
	return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
T
Thomas Graf 已提交
962 963
}

964
struct dst_entry * ip6_route_output(struct net *net, const struct sock *sk,
965
				    struct flowi6 *fl6)
T
Thomas Graf 已提交
966 967 968
{
	int flags = 0;

969 970
	fl6->flowi6_iif = net->loopback_dev->ifindex;

971
	if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr))
972
		flags |= RT6_LOOKUP_F_IFACE;
T
Thomas Graf 已提交
973

974
	if (!ipv6_addr_any(&fl6->saddr))
975
		flags |= RT6_LOOKUP_F_HAS_SADDR;
976 977
	else if (sk)
		flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
978

979
	return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
L
Linus Torvalds 已提交
980 981
}

982
EXPORT_SYMBOL(ip6_route_output);
L
Linus Torvalds 已提交
983

984
struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
985
{
986
	struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
987 988
	struct dst_entry *new = NULL;

989
	rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
990
	if (rt) {
991
		new = &rt->dst;
992

993 994 995
		memset(new + 1, 0, sizeof(*rt) - sizeof(*new));
		rt6_init_peer(rt, net->ipv6.peers);

996
		new->__use = 1;
997 998
		new->input = dst_discard;
		new->output = dst_discard;
999

E
Eric Dumazet 已提交
1000 1001 1002 1003
		if (dst_metrics_read_only(&ort->dst))
			new->_metrics = ort->dst._metrics;
		else
			dst_copy_metrics(new, &ort->dst);
1004 1005 1006 1007
		rt->rt6i_idev = ort->rt6i_idev;
		if (rt->rt6i_idev)
			in6_dev_hold(rt->rt6i_idev);

A
Alexey Dobriyan 已提交
1008
		rt->rt6i_gateway = ort->rt6i_gateway;
1009 1010
		rt->rt6i_flags = ort->rt6i_flags;
		rt6_clean_expires(rt);
1011 1012 1013 1014 1015 1016 1017 1018 1019 1020
		rt->rt6i_metric = 0;

		memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
#ifdef CONFIG_IPV6_SUBTREES
		memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
#endif

		dst_free(new);
	}

1021 1022
	dst_release(dst_orig);
	return new ? new : ERR_PTR(-ENOMEM);
1023 1024
}

L
Linus Torvalds 已提交
1025 1026 1027 1028 1029 1030 1031 1032 1033 1034
/*
 *	Destination cache support functions
 */

static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
{
	struct rt6_info *rt;

	rt = (struct rt6_info *) dst;

1035 1036 1037 1038 1039 1040 1041
	/* All IPV6 dsts are created with ->obsolete set to the value
	 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
	 * into this function always.
	 */
	if (rt->rt6i_genid != rt_genid(dev_net(rt->dst.dev)))
		return NULL;

1042 1043
	if (rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie)) {
		if (rt->rt6i_peer_genid != rt6_peer_genid()) {
1044
			if (!rt6_has_peer(rt))
1045 1046 1047
				rt6_bind_peer(rt, 0);
			rt->rt6i_peer_genid = rt6_peer_genid();
		}
L
Linus Torvalds 已提交
1048
		return dst;
1049
	}
L
Linus Torvalds 已提交
1050 1051 1052 1053 1054 1055 1056 1057
	return NULL;
}

static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
{
	struct rt6_info *rt = (struct rt6_info *) dst;

	if (rt) {
1058 1059 1060 1061 1062 1063
		if (rt->rt6i_flags & RTF_CACHE) {
			if (rt6_check_expired(rt)) {
				ip6_del_rt(rt);
				dst = NULL;
			}
		} else {
L
Linus Torvalds 已提交
1064
			dst_release(dst);
1065 1066
			dst = NULL;
		}
L
Linus Torvalds 已提交
1067
	}
1068
	return dst;
L
Linus Torvalds 已提交
1069 1070 1071 1072 1073 1074
}

static void ip6_link_failure(struct sk_buff *skb)
{
	struct rt6_info *rt;

1075
	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
L
Linus Torvalds 已提交
1076

E
Eric Dumazet 已提交
1077
	rt = (struct rt6_info *) skb_dst(skb);
L
Linus Torvalds 已提交
1078
	if (rt) {
1079 1080 1081
		if (rt->rt6i_flags & RTF_CACHE)
			rt6_update_expires(rt, 0);
		else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
L
Linus Torvalds 已提交
1082 1083 1084 1085
			rt->rt6i_node->fn_sernum = -1;
	}
}

1086 1087
static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
			       struct sk_buff *skb, u32 mtu)
L
Linus Torvalds 已提交
1088 1089 1090
{
	struct rt6_info *rt6 = (struct rt6_info*)dst;

1091
	dst_confirm(dst);
L
Linus Torvalds 已提交
1092
	if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
1093 1094
		struct net *net = dev_net(dst->dev);

L
Linus Torvalds 已提交
1095 1096
		rt6->rt6i_flags |= RTF_MODIFIED;
		if (mtu < IPV6_MIN_MTU) {
1097
			u32 features = dst_metric(dst, RTAX_FEATURES);
L
Linus Torvalds 已提交
1098
			mtu = IPV6_MIN_MTU;
1099 1100
			features |= RTAX_FEATURE_ALLFRAG;
			dst_metric_set(dst, RTAX_FEATURES, features);
L
Linus Torvalds 已提交
1101
		}
1102
		dst_metric_set(dst, RTAX_MTU, mtu);
1103
		rt6_update_expires(rt6, net->ipv6.sysctl.ip6_rt_mtu_expires);
L
Linus Torvalds 已提交
1104 1105 1106
	}
}

1107 1108
void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
		     int oif, u32 mark)
1109 1110 1111 1112 1113 1114 1115 1116
{
	const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
	struct dst_entry *dst;
	struct flowi6 fl6;

	memset(&fl6, 0, sizeof(fl6));
	fl6.flowi6_oif = oif;
	fl6.flowi6_mark = mark;
1117
	fl6.flowi6_flags = 0;
1118 1119 1120 1121 1122 1123
	fl6.daddr = iph->daddr;
	fl6.saddr = iph->saddr;
	fl6.flowlabel = (*(__be32 *) iph) & IPV6_FLOWINFO_MASK;

	dst = ip6_route_output(net, NULL, &fl6);
	if (!dst->error)
1124
		ip6_rt_update_pmtu(dst, NULL, skb, ntohl(mtu));
1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135
	dst_release(dst);
}
EXPORT_SYMBOL_GPL(ip6_update_pmtu);

void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
{
	ip6_update_pmtu(skb, sock_net(sk), mtu,
			sk->sk_bound_dev_if, sk->sk_mark);
}
EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);

1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151
void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
{
	const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
	struct dst_entry *dst;
	struct flowi6 fl6;

	memset(&fl6, 0, sizeof(fl6));
	fl6.flowi6_oif = oif;
	fl6.flowi6_mark = mark;
	fl6.flowi6_flags = 0;
	fl6.daddr = iph->daddr;
	fl6.saddr = iph->saddr;
	fl6.flowlabel = (*(__be32 *) iph) & IPV6_FLOWINFO_MASK;

	dst = ip6_route_output(net, NULL, &fl6);
	if (!dst->error)
1152
		rt6_do_redirect(dst, NULL, skb);
1153 1154 1155 1156 1157 1158 1159 1160 1161 1162
	dst_release(dst);
}
EXPORT_SYMBOL_GPL(ip6_redirect);

void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
{
	ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
}
EXPORT_SYMBOL_GPL(ip6_sk_redirect);

1163
static unsigned int ip6_default_advmss(const struct dst_entry *dst)
L
Linus Torvalds 已提交
1164
{
1165 1166 1167 1168
	struct net_device *dev = dst->dev;
	unsigned int mtu = dst_mtu(dst);
	struct net *net = dev_net(dev);

L
Linus Torvalds 已提交
1169 1170
	mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);

1171 1172
	if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
		mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
L
Linus Torvalds 已提交
1173 1174

	/*
1175 1176 1177
	 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
	 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
	 * IPV6_MAXPLEN is also valid and means: "any MSS,
L
Linus Torvalds 已提交
1178 1179 1180 1181 1182 1183 1184
	 * rely only on pmtu discovery"
	 */
	if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
		mtu = IPV6_MAXPLEN;
	return mtu;
}

1185
static unsigned int ip6_mtu(const struct dst_entry *dst)
1186 1187
{
	struct inet6_dev *idev;
1188 1189 1190 1191 1192 1193
	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);

	if (mtu)
		return mtu;

	mtu = IPV6_MIN_MTU;
1194 1195 1196 1197 1198 1199 1200 1201 1202 1203

	rcu_read_lock();
	idev = __in6_dev_get(dst->dev);
	if (idev)
		mtu = idev->cnf.mtu6;
	rcu_read_unlock();

	return mtu;
}

1204 1205
static struct dst_entry *icmp6_dst_gc_list;
static DEFINE_SPINLOCK(icmp6_dst_lock);
1206

1207
struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
L
Linus Torvalds 已提交
1208
				  struct neighbour *neigh,
1209
				  struct flowi6 *fl6)
L
Linus Torvalds 已提交
1210
{
1211
	struct dst_entry *dst;
L
Linus Torvalds 已提交
1212 1213
	struct rt6_info *rt;
	struct inet6_dev *idev = in6_dev_get(dev);
1214
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
1215

1216
	if (unlikely(!idev))
E
Eric Dumazet 已提交
1217
		return ERR_PTR(-ENODEV);
L
Linus Torvalds 已提交
1218

1219
	rt = ip6_dst_alloc(net, dev, 0, NULL);
1220
	if (unlikely(!rt)) {
L
Linus Torvalds 已提交
1221
		in6_dev_put(idev);
1222
		dst = ERR_PTR(-ENOMEM);
L
Linus Torvalds 已提交
1223 1224 1225 1226 1227
		goto out;
	}

	if (neigh)
		neigh_hold(neigh);
1228
	else {
1229
		neigh = ip6_neigh_lookup(&rt->dst, NULL, &fl6->daddr);
1230
		if (IS_ERR(neigh)) {
1231
			in6_dev_put(idev);
1232 1233 1234
			dst_free(&rt->dst);
			return ERR_CAST(neigh);
		}
1235
	}
L
Linus Torvalds 已提交
1236

1237 1238
	rt->dst.flags |= DST_HOST;
	rt->dst.output  = ip6_output;
1239
	rt->n = neigh;
1240
	atomic_set(&rt->dst.__refcnt, 1);
1241
	rt->rt6i_dst.addr = fl6->daddr;
1242 1243
	rt->rt6i_dst.plen = 128;
	rt->rt6i_idev     = idev;
1244
	dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 255);
L
Linus Torvalds 已提交
1245

1246
	spin_lock_bh(&icmp6_dst_lock);
1247 1248
	rt->dst.next = icmp6_dst_gc_list;
	icmp6_dst_gc_list = &rt->dst;
1249
	spin_unlock_bh(&icmp6_dst_lock);
L
Linus Torvalds 已提交
1250

1251
	fib6_force_start_gc(net);
L
Linus Torvalds 已提交
1252

1253 1254
	dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);

L
Linus Torvalds 已提交
1255
out:
1256
	return dst;
L
Linus Torvalds 已提交
1257 1258
}

1259
int icmp6_dst_gc(void)
L
Linus Torvalds 已提交
1260
{
1261
	struct dst_entry *dst, **pprev;
1262
	int more = 0;
L
Linus Torvalds 已提交
1263

1264 1265
	spin_lock_bh(&icmp6_dst_lock);
	pprev = &icmp6_dst_gc_list;
1266

L
Linus Torvalds 已提交
1267 1268 1269 1270 1271 1272
	while ((dst = *pprev) != NULL) {
		if (!atomic_read(&dst->__refcnt)) {
			*pprev = dst->next;
			dst_free(dst);
		} else {
			pprev = &dst->next;
1273
			++more;
L
Linus Torvalds 已提交
1274 1275 1276
		}
	}

1277
	spin_unlock_bh(&icmp6_dst_lock);
1278

1279
	return more;
L
Linus Torvalds 已提交
1280 1281
}

1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300
static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
			    void *arg)
{
	struct dst_entry *dst, **pprev;

	spin_lock_bh(&icmp6_dst_lock);
	pprev = &icmp6_dst_gc_list;
	while ((dst = *pprev) != NULL) {
		struct rt6_info *rt = (struct rt6_info *) dst;
		if (func(rt, arg)) {
			*pprev = dst->next;
			dst_free(dst);
		} else {
			pprev = &dst->next;
		}
	}
	spin_unlock_bh(&icmp6_dst_lock);
}

1301
static int ip6_dst_gc(struct dst_ops *ops)
L
Linus Torvalds 已提交
1302 1303
{
	unsigned long now = jiffies;
1304
	struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1305 1306 1307 1308 1309
	int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
	int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
	int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
	int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
	unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1310
	int entries;
1311

1312
	entries = dst_entries_get_fast(ops);
1313
	if (time_after(rt_last_gc + rt_min_interval, now) &&
1314
	    entries <= rt_max_size)
L
Linus Torvalds 已提交
1315 1316
		goto out;

1317 1318 1319
	net->ipv6.ip6_rt_gc_expire++;
	fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net);
	net->ipv6.ip6_rt_last_gc = now;
1320 1321
	entries = dst_entries_get_slow(ops);
	if (entries < ops->gc_thresh)
1322
		net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
L
Linus Torvalds 已提交
1323
out:
1324
	net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1325
	return entries > rt_max_size;
L
Linus Torvalds 已提交
1326 1327 1328 1329 1330 1331 1332 1333
}

/* Clean host part of a prefix. Not necessary in radix tree,
   but results in cleaner routing tables.

   Remove it only when all the things will work!
 */

1334
int ip6_dst_hoplimit(struct dst_entry *dst)
L
Linus Torvalds 已提交
1335
{
1336
	int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
1337
	if (hoplimit == 0) {
1338
		struct net_device *dev = dst->dev;
1339 1340 1341 1342 1343
		struct inet6_dev *idev;

		rcu_read_lock();
		idev = __in6_dev_get(dev);
		if (idev)
1344
			hoplimit = idev->cnf.hop_limit;
1345
		else
1346
			hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit;
1347
		rcu_read_unlock();
L
Linus Torvalds 已提交
1348 1349 1350
	}
	return hoplimit;
}
1351
EXPORT_SYMBOL(ip6_dst_hoplimit);
L
Linus Torvalds 已提交
1352 1353 1354 1355 1356

/*
 *
 */

1357
int ip6_route_add(struct fib6_config *cfg)
L
Linus Torvalds 已提交
1358 1359
{
	int err;
1360
	struct net *net = cfg->fc_nlinfo.nl_net;
L
Linus Torvalds 已提交
1361 1362 1363
	struct rt6_info *rt = NULL;
	struct net_device *dev = NULL;
	struct inet6_dev *idev = NULL;
T
Thomas Graf 已提交
1364
	struct fib6_table *table;
L
Linus Torvalds 已提交
1365 1366
	int addr_type;

1367
	if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
L
Linus Torvalds 已提交
1368 1369
		return -EINVAL;
#ifndef CONFIG_IPV6_SUBTREES
1370
	if (cfg->fc_src_len)
L
Linus Torvalds 已提交
1371 1372
		return -EINVAL;
#endif
1373
	if (cfg->fc_ifindex) {
L
Linus Torvalds 已提交
1374
		err = -ENODEV;
1375
		dev = dev_get_by_index(net, cfg->fc_ifindex);
L
Linus Torvalds 已提交
1376 1377 1378 1379 1380 1381 1382
		if (!dev)
			goto out;
		idev = in6_dev_get(dev);
		if (!idev)
			goto out;
	}

1383 1384
	if (cfg->fc_metric == 0)
		cfg->fc_metric = IP6_RT_PRIO_USER;
L
Linus Torvalds 已提交
1385

1386
	err = -ENOBUFS;
1387 1388
	if (cfg->fc_nlinfo.nlh &&
	    !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1389
		table = fib6_get_table(net, cfg->fc_table);
1390
		if (!table) {
1391
			pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1392 1393 1394 1395 1396
			table = fib6_new_table(net, cfg->fc_table);
		}
	} else {
		table = fib6_new_table(net, cfg->fc_table);
	}
1397 1398

	if (!table)
T
Thomas Graf 已提交
1399 1400
		goto out;

1401
	rt = ip6_dst_alloc(net, NULL, DST_NOCOUNT, table);
L
Linus Torvalds 已提交
1402

1403
	if (!rt) {
L
Linus Torvalds 已提交
1404 1405 1406 1407
		err = -ENOMEM;
		goto out;
	}

1408 1409 1410 1411 1412
	if (cfg->fc_flags & RTF_EXPIRES)
		rt6_set_expires(rt, jiffies +
				clock_t_to_jiffies(cfg->fc_expires));
	else
		rt6_clean_expires(rt);
L
Linus Torvalds 已提交
1413

1414 1415 1416 1417 1418
	if (cfg->fc_protocol == RTPROT_UNSPEC)
		cfg->fc_protocol = RTPROT_BOOT;
	rt->rt6i_protocol = cfg->fc_protocol;

	addr_type = ipv6_addr_type(&cfg->fc_dst);
L
Linus Torvalds 已提交
1419 1420

	if (addr_type & IPV6_ADDR_MULTICAST)
1421
		rt->dst.input = ip6_mc_input;
1422 1423
	else if (cfg->fc_flags & RTF_LOCAL)
		rt->dst.input = ip6_input;
L
Linus Torvalds 已提交
1424
	else
1425
		rt->dst.input = ip6_forward;
L
Linus Torvalds 已提交
1426

1427
	rt->dst.output = ip6_output;
L
Linus Torvalds 已提交
1428

1429 1430
	ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
	rt->rt6i_dst.plen = cfg->fc_dst_len;
L
Linus Torvalds 已提交
1431
	if (rt->rt6i_dst.plen == 128)
1432
	       rt->dst.flags |= DST_HOST;
L
Linus Torvalds 已提交
1433

1434 1435 1436 1437 1438 1439 1440 1441
	if (!(rt->dst.flags & DST_HOST) && cfg->fc_mx) {
		u32 *metrics = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
		if (!metrics) {
			err = -ENOMEM;
			goto out;
		}
		dst_init_metrics(&rt->dst, metrics, 0);
	}
L
Linus Torvalds 已提交
1442
#ifdef CONFIG_IPV6_SUBTREES
1443 1444
	ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
	rt->rt6i_src.plen = cfg->fc_src_len;
L
Linus Torvalds 已提交
1445 1446
#endif

1447
	rt->rt6i_metric = cfg->fc_metric;
L
Linus Torvalds 已提交
1448 1449 1450 1451

	/* We cannot add true routes via loopback here,
	   they would result in kernel looping; promote them to reject routes
	 */
1452
	if ((cfg->fc_flags & RTF_REJECT) ||
1453 1454 1455
	    (dev && (dev->flags & IFF_LOOPBACK) &&
	     !(addr_type & IPV6_ADDR_LOOPBACK) &&
	     !(cfg->fc_flags & RTF_LOCAL))) {
L
Linus Torvalds 已提交
1456
		/* hold loopback dev/idev if we haven't done so. */
1457
		if (dev != net->loopback_dev) {
L
Linus Torvalds 已提交
1458 1459 1460 1461
			if (dev) {
				dev_put(dev);
				in6_dev_put(idev);
			}
1462
			dev = net->loopback_dev;
L
Linus Torvalds 已提交
1463 1464 1465 1466 1467 1468 1469
			dev_hold(dev);
			idev = in6_dev_get(dev);
			if (!idev) {
				err = -ENODEV;
				goto out;
			}
		}
1470 1471 1472
		rt->dst.output = ip6_pkt_discard_out;
		rt->dst.input = ip6_pkt_discard;
		rt->dst.error = -ENETUNREACH;
L
Linus Torvalds 已提交
1473 1474 1475 1476
		rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
		goto install_route;
	}

1477
	if (cfg->fc_flags & RTF_GATEWAY) {
1478
		const struct in6_addr *gw_addr;
L
Linus Torvalds 已提交
1479 1480
		int gwa_type;

1481
		gw_addr = &cfg->fc_gateway;
A
Alexey Dobriyan 已提交
1482
		rt->rt6i_gateway = *gw_addr;
L
Linus Torvalds 已提交
1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495
		gwa_type = ipv6_addr_type(gw_addr);

		if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
			struct rt6_info *grt;

			/* IPv6 strictly inhibits using not link-local
			   addresses as nexthop address.
			   Otherwise, router will not able to send redirects.
			   It is very good, but in some (rare!) circumstances
			   (SIT, PtP, NBMA NOARP links) it is handy to allow
			   some exceptions. --ANK
			 */
			err = -EINVAL;
1496
			if (!(gwa_type & IPV6_ADDR_UNICAST))
L
Linus Torvalds 已提交
1497 1498
				goto out;

1499
			grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
L
Linus Torvalds 已提交
1500 1501

			err = -EHOSTUNREACH;
1502
			if (!grt)
L
Linus Torvalds 已提交
1503 1504
				goto out;
			if (dev) {
1505
				if (dev != grt->dst.dev) {
1506
					dst_release(&grt->dst);
L
Linus Torvalds 已提交
1507 1508 1509
					goto out;
				}
			} else {
1510
				dev = grt->dst.dev;
L
Linus Torvalds 已提交
1511 1512 1513 1514
				idev = grt->rt6i_idev;
				dev_hold(dev);
				in6_dev_hold(grt->rt6i_idev);
			}
1515
			if (!(grt->rt6i_flags & RTF_GATEWAY))
L
Linus Torvalds 已提交
1516
				err = 0;
1517
			dst_release(&grt->dst);
L
Linus Torvalds 已提交
1518 1519 1520 1521 1522

			if (err)
				goto out;
		}
		err = -EINVAL;
1523
		if (!dev || (dev->flags & IFF_LOOPBACK))
L
Linus Torvalds 已提交
1524 1525 1526 1527
			goto out;
	}

	err = -ENODEV;
1528
	if (!dev)
L
Linus Torvalds 已提交
1529 1530
		goto out;

1531 1532 1533 1534 1535
	if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
		if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
			err = -EINVAL;
			goto out;
		}
A
Alexey Dobriyan 已提交
1536
		rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1537 1538 1539 1540
		rt->rt6i_prefsrc.plen = 128;
	} else
		rt->rt6i_prefsrc.plen = 0;

1541
	if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1542
		err = rt6_bind_neighbour(rt, dev);
1543
		if (err)
L
Linus Torvalds 已提交
1544 1545 1546
			goto out;
	}

1547
	rt->rt6i_flags = cfg->fc_flags;
L
Linus Torvalds 已提交
1548 1549

install_route:
1550 1551 1552 1553 1554
	if (cfg->fc_mx) {
		struct nlattr *nla;
		int remaining;

		nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1555
			int type = nla_type(nla);
1556 1557 1558

			if (type) {
				if (type > RTAX_MAX) {
L
Linus Torvalds 已提交
1559 1560 1561
					err = -EINVAL;
					goto out;
				}
1562

1563
				dst_metric_set(&rt->dst, type, nla_get_u32(nla));
L
Linus Torvalds 已提交
1564 1565 1566 1567
			}
		}
	}

1568
	rt->dst.dev = dev;
L
Linus Torvalds 已提交
1569
	rt->rt6i_idev = idev;
T
Thomas Graf 已提交
1570
	rt->rt6i_table = table;
1571

1572
	cfg->fc_nlinfo.nl_net = dev_net(dev);
1573

1574
	return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
L
Linus Torvalds 已提交
1575 1576 1577 1578 1579 1580 1581

out:
	if (dev)
		dev_put(dev);
	if (idev)
		in6_dev_put(idev);
	if (rt)
1582
		dst_free(&rt->dst);
L
Linus Torvalds 已提交
1583 1584 1585
	return err;
}

1586
static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
L
Linus Torvalds 已提交
1587 1588
{
	int err;
T
Thomas Graf 已提交
1589
	struct fib6_table *table;
1590
	struct net *net = dev_net(rt->dst.dev);
L
Linus Torvalds 已提交
1591

1592
	if (rt == net->ipv6.ip6_null_entry)
1593 1594
		return -ENOENT;

T
Thomas Graf 已提交
1595 1596
	table = rt->rt6i_table;
	write_lock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1597

1598
	err = fib6_del(rt, info);
1599
	dst_release(&rt->dst);
L
Linus Torvalds 已提交
1600

T
Thomas Graf 已提交
1601
	write_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1602 1603 1604 1605

	return err;
}

1606 1607
int ip6_del_rt(struct rt6_info *rt)
{
1608
	struct nl_info info = {
1609
		.nl_net = dev_net(rt->dst.dev),
1610
	};
1611
	return __ip6_del_rt(rt, &info);
1612 1613
}

1614
static int ip6_route_del(struct fib6_config *cfg)
L
Linus Torvalds 已提交
1615
{
T
Thomas Graf 已提交
1616
	struct fib6_table *table;
L
Linus Torvalds 已提交
1617 1618 1619 1620
	struct fib6_node *fn;
	struct rt6_info *rt;
	int err = -ESRCH;

1621
	table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
1622
	if (!table)
T
Thomas Graf 已提交
1623 1624 1625
		return err;

	read_lock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1626

T
Thomas Graf 已提交
1627
	fn = fib6_locate(&table->tb6_root,
1628 1629
			 &cfg->fc_dst, cfg->fc_dst_len,
			 &cfg->fc_src, cfg->fc_src_len);
1630

L
Linus Torvalds 已提交
1631
	if (fn) {
1632
		for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1633
			if (cfg->fc_ifindex &&
1634 1635
			    (!rt->dst.dev ||
			     rt->dst.dev->ifindex != cfg->fc_ifindex))
L
Linus Torvalds 已提交
1636
				continue;
1637 1638
			if (cfg->fc_flags & RTF_GATEWAY &&
			    !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
L
Linus Torvalds 已提交
1639
				continue;
1640
			if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
L
Linus Torvalds 已提交
1641
				continue;
1642
			dst_hold(&rt->dst);
T
Thomas Graf 已提交
1643
			read_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1644

1645
			return __ip6_del_rt(rt, &cfg->fc_nlinfo);
L
Linus Torvalds 已提交
1646 1647
		}
	}
T
Thomas Graf 已提交
1648
	read_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1649 1650 1651 1652

	return err;
}

1653
static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
1654
{
1655
	struct net *net = dev_net(skb->dev);
1656
	struct netevent_redirect netevent;
1657 1658 1659
	struct rt6_info *rt, *nrt = NULL;
	const struct in6_addr *target;
	struct ndisc_options ndopts;
1660 1661
	const struct in6_addr *dest;
	struct neighbour *old_neigh;
1662 1663 1664
	struct inet6_dev *in6_dev;
	struct neighbour *neigh;
	struct icmp6hdr *icmph;
1665 1666
	int optlen, on_link;
	u8 *lladdr;
1667 1668 1669 1670 1671

	optlen = skb->tail - skb->transport_header;
	optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);

	if (optlen < 0) {
1672
		net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
1673 1674 1675 1676 1677 1678 1679 1680
		return;
	}

	icmph = icmp6_hdr(skb);
	target = (const struct in6_addr *) (icmph + 1);
	dest = target + 1;

	if (ipv6_addr_is_multicast(dest)) {
1681
		net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
1682 1683 1684
		return;
	}

1685
	on_link = 0;
1686 1687 1688 1689
	if (ipv6_addr_equal(dest, target)) {
		on_link = 1;
	} else if (ipv6_addr_type(target) !=
		   (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1690
		net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708
		return;
	}

	in6_dev = __in6_dev_get(skb->dev);
	if (!in6_dev)
		return;
	if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
		return;

	/* RFC2461 8.1:
	 *	The IP source address of the Redirect MUST be the same as the current
	 *	first-hop router for the specified ICMP Destination Address.
	 */

	if (!ndisc_parse_options((u8*)(dest + 1), optlen, &ndopts)) {
		net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
		return;
	}
1709 1710

	lladdr = NULL;
1711 1712 1713 1714 1715 1716 1717 1718 1719
	if (ndopts.nd_opts_tgt_lladdr) {
		lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
					     skb->dev);
		if (!lladdr) {
			net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
			return;
		}
	}

1720 1721 1722
	rt = (struct rt6_info *) dst;
	if (rt == net->ipv6.ip6_null_entry) {
		net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
1723
		return;
1724
	}
1725

1726 1727 1728 1729 1730
	/* Redirect received -> path was valid.
	 * Look, redirects are sent only in response to data packets,
	 * so that this nexthop apparently is reachable. --ANK
	 */
	dst_confirm(&rt->dst);
1731

1732 1733 1734
	neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
	if (!neigh)
		return;
1735

1736 1737 1738
	/* Duplicate redirect: silently ignore. */
	old_neigh = rt->n;
	if (neigh == old_neigh)
1739
		goto out;
L
Linus Torvalds 已提交
1740 1741 1742 1743 1744

	/*
	 *	We have finally decided to accept it.
	 */

1745
	neigh_update(neigh, lladdr, NUD_STALE,
L
Linus Torvalds 已提交
1746 1747 1748 1749 1750 1751
		     NEIGH_UPDATE_F_WEAK_OVERRIDE|
		     NEIGH_UPDATE_F_OVERRIDE|
		     (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
				     NEIGH_UPDATE_F_ISROUTER))
		     );

E
Eric Dumazet 已提交
1752
	nrt = ip6_rt_copy(rt, dest);
1753
	if (!nrt)
L
Linus Torvalds 已提交
1754 1755 1756 1757 1758 1759
		goto out;

	nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
	if (on_link)
		nrt->rt6i_flags &= ~RTF_GATEWAY;

A
Alexey Dobriyan 已提交
1760
	nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
1761
	nrt->n = neigh_clone(neigh);
L
Linus Torvalds 已提交
1762

1763
	if (ip6_ins_rt(nrt))
L
Linus Torvalds 已提交
1764 1765
		goto out;

1766
	netevent.old = &rt->dst;
1767
	netevent.old_neigh = old_neigh;
1768
	netevent.new = &nrt->dst;
1769 1770
	netevent.new_neigh = neigh;
	netevent.daddr = dest;
1771 1772
	call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);

1773
	if (rt->rt6i_flags & RTF_CACHE) {
1774
		rt = (struct rt6_info *) dst_clone(&rt->dst);
1775
		ip6_del_rt(rt);
L
Linus Torvalds 已提交
1776 1777 1778
	}

out:
1779
	neigh_release(neigh);
1780 1781
}

L
Linus Torvalds 已提交
1782 1783 1784 1785
/*
 *	Misc support functions
 */

1786
static struct rt6_info *ip6_rt_copy(struct rt6_info *ort,
E
Eric Dumazet 已提交
1787
				    const struct in6_addr *dest)
L
Linus Torvalds 已提交
1788
{
1789
	struct net *net = dev_net(ort->dst.dev);
1790 1791
	struct rt6_info *rt = ip6_dst_alloc(net, ort->dst.dev, 0,
					    ort->rt6i_table);
L
Linus Torvalds 已提交
1792 1793

	if (rt) {
1794 1795
		rt->dst.input = ort->dst.input;
		rt->dst.output = ort->dst.output;
1796
		rt->dst.flags |= DST_HOST;
1797

A
Alexey Dobriyan 已提交
1798
		rt->rt6i_dst.addr = *dest;
1799
		rt->rt6i_dst.plen = 128;
1800
		dst_copy_metrics(&rt->dst, &ort->dst);
1801
		rt->dst.error = ort->dst.error;
L
Linus Torvalds 已提交
1802 1803 1804
		rt->rt6i_idev = ort->rt6i_idev;
		if (rt->rt6i_idev)
			in6_dev_hold(rt->rt6i_idev);
1805
		rt->dst.lastuse = jiffies;
L
Linus Torvalds 已提交
1806

A
Alexey Dobriyan 已提交
1807
		rt->rt6i_gateway = ort->rt6i_gateway;
1808 1809 1810 1811 1812 1813
		rt->rt6i_flags = ort->rt6i_flags;
		if ((ort->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) ==
		    (RTF_DEFAULT | RTF_ADDRCONF))
			rt6_set_from(rt, ort);
		else
			rt6_clean_expires(rt);
L
Linus Torvalds 已提交
1814 1815 1816 1817 1818
		rt->rt6i_metric = 0;

#ifdef CONFIG_IPV6_SUBTREES
		memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
#endif
1819
		memcpy(&rt->rt6i_prefsrc, &ort->rt6i_prefsrc, sizeof(struct rt6key));
T
Thomas Graf 已提交
1820
		rt->rt6i_table = ort->rt6i_table;
L
Linus Torvalds 已提交
1821 1822 1823 1824
	}
	return rt;
}

1825
#ifdef CONFIG_IPV6_ROUTE_INFO
1826
static struct rt6_info *rt6_get_route_info(struct net *net,
1827 1828
					   const struct in6_addr *prefix, int prefixlen,
					   const struct in6_addr *gwaddr, int ifindex)
1829 1830 1831
{
	struct fib6_node *fn;
	struct rt6_info *rt = NULL;
T
Thomas Graf 已提交
1832 1833
	struct fib6_table *table;

1834
	table = fib6_get_table(net, RT6_TABLE_INFO);
1835
	if (!table)
T
Thomas Graf 已提交
1836
		return NULL;
1837

T
Thomas Graf 已提交
1838 1839
	write_lock_bh(&table->tb6_lock);
	fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1840 1841 1842
	if (!fn)
		goto out;

1843
	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1844
		if (rt->dst.dev->ifindex != ifindex)
1845 1846 1847 1848 1849
			continue;
		if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
			continue;
		if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
			continue;
1850
		dst_hold(&rt->dst);
1851 1852 1853
		break;
	}
out:
T
Thomas Graf 已提交
1854
	write_unlock_bh(&table->tb6_lock);
1855 1856 1857
	return rt;
}

1858
static struct rt6_info *rt6_add_route_info(struct net *net,
1859 1860
					   const struct in6_addr *prefix, int prefixlen,
					   const struct in6_addr *gwaddr, int ifindex,
1861
					   unsigned int pref)
1862
{
1863 1864
	struct fib6_config cfg = {
		.fc_table	= RT6_TABLE_INFO,
1865
		.fc_metric	= IP6_RT_PRIO_USER,
1866 1867 1868 1869
		.fc_ifindex	= ifindex,
		.fc_dst_len	= prefixlen,
		.fc_flags	= RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
				  RTF_UP | RTF_PREF(pref),
1870 1871 1872
		.fc_nlinfo.pid = 0,
		.fc_nlinfo.nlh = NULL,
		.fc_nlinfo.nl_net = net,
1873 1874
	};

A
Alexey Dobriyan 已提交
1875 1876
	cfg.fc_dst = *prefix;
	cfg.fc_gateway = *gwaddr;
1877

1878 1879
	/* We should treat it as a default route if prefix length is 0. */
	if (!prefixlen)
1880
		cfg.fc_flags |= RTF_DEFAULT;
1881

1882
	ip6_route_add(&cfg);
1883

1884
	return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
1885 1886 1887
}
#endif

1888
struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
1889
{
L
Linus Torvalds 已提交
1890
	struct rt6_info *rt;
T
Thomas Graf 已提交
1891
	struct fib6_table *table;
L
Linus Torvalds 已提交
1892

1893
	table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
1894
	if (!table)
T
Thomas Graf 已提交
1895
		return NULL;
L
Linus Torvalds 已提交
1896

T
Thomas Graf 已提交
1897
	write_lock_bh(&table->tb6_lock);
1898
	for (rt = table->tb6_root.leaf; rt; rt=rt->dst.rt6_next) {
1899
		if (dev == rt->dst.dev &&
1900
		    ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
L
Linus Torvalds 已提交
1901 1902 1903 1904
		    ipv6_addr_equal(&rt->rt6i_gateway, addr))
			break;
	}
	if (rt)
1905
		dst_hold(&rt->dst);
T
Thomas Graf 已提交
1906
	write_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1907 1908 1909
	return rt;
}

1910
struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
1911 1912
				     struct net_device *dev,
				     unsigned int pref)
L
Linus Torvalds 已提交
1913
{
1914 1915
	struct fib6_config cfg = {
		.fc_table	= RT6_TABLE_DFLT,
1916
		.fc_metric	= IP6_RT_PRIO_USER,
1917 1918 1919
		.fc_ifindex	= dev->ifindex,
		.fc_flags	= RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
				  RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1920 1921
		.fc_nlinfo.pid = 0,
		.fc_nlinfo.nlh = NULL,
1922
		.fc_nlinfo.nl_net = dev_net(dev),
1923
	};
L
Linus Torvalds 已提交
1924

A
Alexey Dobriyan 已提交
1925
	cfg.fc_gateway = *gwaddr;
L
Linus Torvalds 已提交
1926

1927
	ip6_route_add(&cfg);
L
Linus Torvalds 已提交
1928 1929 1930 1931

	return rt6_get_dflt_router(gwaddr, dev);
}

1932
void rt6_purge_dflt_routers(struct net *net)
L
Linus Torvalds 已提交
1933 1934
{
	struct rt6_info *rt;
T
Thomas Graf 已提交
1935 1936 1937
	struct fib6_table *table;

	/* NOTE: Keep consistent with rt6_get_dflt_router */
1938
	table = fib6_get_table(net, RT6_TABLE_DFLT);
1939
	if (!table)
T
Thomas Graf 已提交
1940
		return;
L
Linus Torvalds 已提交
1941 1942

restart:
T
Thomas Graf 已提交
1943
	read_lock_bh(&table->tb6_lock);
1944
	for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
L
Linus Torvalds 已提交
1945
		if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1946
			dst_hold(&rt->dst);
T
Thomas Graf 已提交
1947
			read_unlock_bh(&table->tb6_lock);
1948
			ip6_del_rt(rt);
L
Linus Torvalds 已提交
1949 1950 1951
			goto restart;
		}
	}
T
Thomas Graf 已提交
1952
	read_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1953 1954
}

1955 1956
static void rtmsg_to_fib6_config(struct net *net,
				 struct in6_rtmsg *rtmsg,
1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968
				 struct fib6_config *cfg)
{
	memset(cfg, 0, sizeof(*cfg));

	cfg->fc_table = RT6_TABLE_MAIN;
	cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
	cfg->fc_metric = rtmsg->rtmsg_metric;
	cfg->fc_expires = rtmsg->rtmsg_info;
	cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
	cfg->fc_src_len = rtmsg->rtmsg_src_len;
	cfg->fc_flags = rtmsg->rtmsg_flags;

1969
	cfg->fc_nlinfo.nl_net = net;
1970

A
Alexey Dobriyan 已提交
1971 1972 1973
	cfg->fc_dst = rtmsg->rtmsg_dst;
	cfg->fc_src = rtmsg->rtmsg_src;
	cfg->fc_gateway = rtmsg->rtmsg_gateway;
1974 1975
}

1976
int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
L
Linus Torvalds 已提交
1977
{
1978
	struct fib6_config cfg;
L
Linus Torvalds 已提交
1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990
	struct in6_rtmsg rtmsg;
	int err;

	switch(cmd) {
	case SIOCADDRT:		/* Add a route */
	case SIOCDELRT:		/* Delete a route */
		if (!capable(CAP_NET_ADMIN))
			return -EPERM;
		err = copy_from_user(&rtmsg, arg,
				     sizeof(struct in6_rtmsg));
		if (err)
			return -EFAULT;
1991

1992
		rtmsg_to_fib6_config(net, &rtmsg, &cfg);
1993

L
Linus Torvalds 已提交
1994 1995 1996
		rtnl_lock();
		switch (cmd) {
		case SIOCADDRT:
1997
			err = ip6_route_add(&cfg);
L
Linus Torvalds 已提交
1998 1999
			break;
		case SIOCDELRT:
2000
			err = ip6_route_del(&cfg);
L
Linus Torvalds 已提交
2001 2002 2003 2004 2005 2006 2007
			break;
		default:
			err = -EINVAL;
		}
		rtnl_unlock();

		return err;
2008
	}
L
Linus Torvalds 已提交
2009 2010 2011 2012 2013 2014 2015 2016

	return -EINVAL;
}

/*
 *	Drop the packet on the floor
 */

2017
static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
L
Linus Torvalds 已提交
2018
{
2019
	int type;
E
Eric Dumazet 已提交
2020
	struct dst_entry *dst = skb_dst(skb);
2021 2022
	switch (ipstats_mib_noroutes) {
	case IPSTATS_MIB_INNOROUTES:
2023
		type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
U
Ulrich Weber 已提交
2024
		if (type == IPV6_ADDR_ANY) {
2025 2026
			IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
				      IPSTATS_MIB_INADDRERRORS);
2027 2028 2029 2030
			break;
		}
		/* FALLTHROUGH */
	case IPSTATS_MIB_OUTNOROUTES:
2031 2032
		IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
			      ipstats_mib_noroutes);
2033 2034
		break;
	}
2035
	icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
L
Linus Torvalds 已提交
2036 2037 2038 2039
	kfree_skb(skb);
	return 0;
}

2040 2041
static int ip6_pkt_discard(struct sk_buff *skb)
{
2042
	return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2043 2044
}

2045
static int ip6_pkt_discard_out(struct sk_buff *skb)
L
Linus Torvalds 已提交
2046
{
E
Eric Dumazet 已提交
2047
	skb->dev = skb_dst(skb)->dev;
2048
	return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
L
Linus Torvalds 已提交
2049 2050
}

2051 2052
#ifdef CONFIG_IPV6_MULTIPLE_TABLES

2053 2054
static int ip6_pkt_prohibit(struct sk_buff *skb)
{
2055
	return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2056 2057 2058 2059
}

static int ip6_pkt_prohibit_out(struct sk_buff *skb)
{
E
Eric Dumazet 已提交
2060
	skb->dev = skb_dst(skb)->dev;
2061
	return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2062 2063
}

2064 2065
#endif

L
Linus Torvalds 已提交
2066 2067 2068 2069 2070 2071
/*
 *	Allocate a dst for local (unicast / anycast) address.
 */

struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
				    const struct in6_addr *addr,
2072
				    bool anycast)
L
Linus Torvalds 已提交
2073
{
2074
	struct net *net = dev_net(idev->dev);
2075
	struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev, 0, NULL);
2076
	int err;
L
Linus Torvalds 已提交
2077

2078
	if (!rt) {
2079
		net_warn_ratelimited("Maximum number of routes reached, consider increasing route/max_size\n");
L
Linus Torvalds 已提交
2080
		return ERR_PTR(-ENOMEM);
2081
	}
L
Linus Torvalds 已提交
2082 2083 2084

	in6_dev_hold(idev);

2085
	rt->dst.flags |= DST_HOST;
2086 2087
	rt->dst.input = ip6_input;
	rt->dst.output = ip6_output;
L
Linus Torvalds 已提交
2088 2089 2090
	rt->rt6i_idev = idev;

	rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2091 2092 2093
	if (anycast)
		rt->rt6i_flags |= RTF_ANYCAST;
	else
L
Linus Torvalds 已提交
2094
		rt->rt6i_flags |= RTF_LOCAL;
2095
	err = rt6_bind_neighbour(rt, rt->dst.dev);
2096
	if (err) {
2097
		dst_free(&rt->dst);
2098
		return ERR_PTR(err);
L
Linus Torvalds 已提交
2099 2100
	}

A
Alexey Dobriyan 已提交
2101
	rt->rt6i_dst.addr = *addr;
L
Linus Torvalds 已提交
2102
	rt->rt6i_dst.plen = 128;
2103
	rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
L
Linus Torvalds 已提交
2104

2105
	atomic_set(&rt->dst.__refcnt, 1);
L
Linus Torvalds 已提交
2106 2107 2108 2109

	return rt;
}

2110 2111
int ip6_route_get_saddr(struct net *net,
			struct rt6_info *rt,
2112
			const struct in6_addr *daddr,
2113 2114 2115 2116 2117 2118
			unsigned int prefs,
			struct in6_addr *saddr)
{
	struct inet6_dev *idev = ip6_dst_idev((struct dst_entry*)rt);
	int err = 0;
	if (rt->rt6i_prefsrc.plen)
A
Alexey Dobriyan 已提交
2119
		*saddr = rt->rt6i_prefsrc.addr;
2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138
	else
		err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
					 daddr, prefs, saddr);
	return err;
}

/* remove deleted ip from prefsrc entries */
struct arg_dev_net_ip {
	struct net_device *dev;
	struct net *net;
	struct in6_addr *addr;
};

static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
{
	struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
	struct net *net = ((struct arg_dev_net_ip *)arg)->net;
	struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;

2139
	if (((void *)rt->dst.dev == dev || !dev) &&
2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158
	    rt != net->ipv6.ip6_null_entry &&
	    ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
		/* remove prefsrc entry */
		rt->rt6i_prefsrc.plen = 0;
	}
	return 0;
}

void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
{
	struct net *net = dev_net(ifp->idev->dev);
	struct arg_dev_net_ip adni = {
		.dev = ifp->idev->dev,
		.net = net,
		.addr = &ifp->addr,
	};
	fib6_clean_all(net, fib6_remove_prefsrc, 0, &adni);
}

2159 2160 2161 2162 2163
struct arg_dev_net {
	struct net_device *dev;
	struct net *net;
};

L
Linus Torvalds 已提交
2164 2165
static int fib6_ifdown(struct rt6_info *rt, void *arg)
{
S
stephen hemminger 已提交
2166 2167
	const struct arg_dev_net *adn = arg;
	const struct net_device *dev = adn->dev;
2168

2169
	if ((rt->dst.dev == dev || !dev) &&
2170
	    rt != adn->net->ipv6.ip6_null_entry)
L
Linus Torvalds 已提交
2171
		return -1;
2172

L
Linus Torvalds 已提交
2173 2174 2175
	return 0;
}

2176
void rt6_ifdown(struct net *net, struct net_device *dev)
L
Linus Torvalds 已提交
2177
{
2178 2179 2180 2181 2182 2183
	struct arg_dev_net adn = {
		.dev = dev,
		.net = net,
	};

	fib6_clean_all(net, fib6_ifdown, 0, &adn);
2184
	icmp6_clean_all(fib6_ifdown, &adn);
L
Linus Torvalds 已提交
2185 2186
}

2187
struct rt6_mtu_change_arg {
L
Linus Torvalds 已提交
2188
	struct net_device *dev;
2189
	unsigned int mtu;
L
Linus Torvalds 已提交
2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203
};

static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
{
	struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
	struct inet6_dev *idev;

	/* In IPv6 pmtu discovery is not optional,
	   so that RTAX_MTU lock cannot disable it.
	   We still use this lock to block changes
	   caused by addrconf/ndisc.
	*/

	idev = __in6_dev_get(arg->dev);
2204
	if (!idev)
L
Linus Torvalds 已提交
2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220
		return 0;

	/* For administrative MTU increase, there is no way to discover
	   IPv6 PMTU increase, so PMTU increase should be updated here.
	   Since RFC 1981 doesn't include administrative MTU increase
	   update PMTU increase is a MUST. (i.e. jumbo frame)
	 */
	/*
	   If new MTU is less than route PMTU, this new MTU will be the
	   lowest MTU in the path, update the route PMTU to reflect PMTU
	   decreases; if new MTU is greater than route PMTU, and the
	   old MTU is the lowest MTU in the path, update the route PMTU
	   to reflect the increase. In this case if the other nodes' MTU
	   also have the lowest MTU, TOO BIG MESSAGE will be lead to
	   PMTU discouvery.
	 */
2221
	if (rt->dst.dev == arg->dev &&
2222 2223 2224 2225
	    !dst_metric_locked(&rt->dst, RTAX_MTU) &&
	    (dst_mtu(&rt->dst) >= arg->mtu ||
	     (dst_mtu(&rt->dst) < arg->mtu &&
	      dst_mtu(&rt->dst) == idev->cnf.mtu6))) {
2226
		dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2227
	}
L
Linus Torvalds 已提交
2228 2229 2230
	return 0;
}

2231
void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
L
Linus Torvalds 已提交
2232
{
T
Thomas Graf 已提交
2233 2234 2235 2236
	struct rt6_mtu_change_arg arg = {
		.dev = dev,
		.mtu = mtu,
	};
L
Linus Torvalds 已提交
2237

2238
	fib6_clean_all(dev_net(dev), rt6_mtu_change_route, 0, &arg);
L
Linus Torvalds 已提交
2239 2240
}

2241
static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2242
	[RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2243
	[RTA_OIF]               = { .type = NLA_U32 },
2244
	[RTA_IIF]		= { .type = NLA_U32 },
2245 2246 2247 2248 2249 2250
	[RTA_PRIORITY]          = { .type = NLA_U32 },
	[RTA_METRICS]           = { .type = NLA_NESTED },
};

static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
			      struct fib6_config *cfg)
L
Linus Torvalds 已提交
2251
{
2252 2253 2254
	struct rtmsg *rtm;
	struct nlattr *tb[RTA_MAX+1];
	int err;
L
Linus Torvalds 已提交
2255

2256 2257 2258
	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
	if (err < 0)
		goto errout;
L
Linus Torvalds 已提交
2259

2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272
	err = -EINVAL;
	rtm = nlmsg_data(nlh);
	memset(cfg, 0, sizeof(*cfg));

	cfg->fc_table = rtm->rtm_table;
	cfg->fc_dst_len = rtm->rtm_dst_len;
	cfg->fc_src_len = rtm->rtm_src_len;
	cfg->fc_flags = RTF_UP;
	cfg->fc_protocol = rtm->rtm_protocol;

	if (rtm->rtm_type == RTN_UNREACHABLE)
		cfg->fc_flags |= RTF_REJECT;

2273 2274 2275
	if (rtm->rtm_type == RTN_LOCAL)
		cfg->fc_flags |= RTF_LOCAL;

2276 2277
	cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
	cfg->fc_nlinfo.nlh = nlh;
2278
	cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2279 2280 2281 2282

	if (tb[RTA_GATEWAY]) {
		nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
		cfg->fc_flags |= RTF_GATEWAY;
L
Linus Torvalds 已提交
2283
	}
2284 2285 2286 2287 2288 2289 2290 2291

	if (tb[RTA_DST]) {
		int plen = (rtm->rtm_dst_len + 7) >> 3;

		if (nla_len(tb[RTA_DST]) < plen)
			goto errout;

		nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
L
Linus Torvalds 已提交
2292
	}
2293 2294 2295 2296 2297 2298 2299 2300

	if (tb[RTA_SRC]) {
		int plen = (rtm->rtm_src_len + 7) >> 3;

		if (nla_len(tb[RTA_SRC]) < plen)
			goto errout;

		nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
L
Linus Torvalds 已提交
2301
	}
2302

2303 2304 2305
	if (tb[RTA_PREFSRC])
		nla_memcpy(&cfg->fc_prefsrc, tb[RTA_PREFSRC], 16);

2306 2307 2308 2309 2310 2311 2312 2313 2314
	if (tb[RTA_OIF])
		cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);

	if (tb[RTA_PRIORITY])
		cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);

	if (tb[RTA_METRICS]) {
		cfg->fc_mx = nla_data(tb[RTA_METRICS]);
		cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
L
Linus Torvalds 已提交
2315
	}
2316 2317 2318 2319 2320 2321 2322

	if (tb[RTA_TABLE])
		cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);

	err = 0;
errout:
	return err;
L
Linus Torvalds 已提交
2323 2324
}

2325
static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
L
Linus Torvalds 已提交
2326
{
2327 2328
	struct fib6_config cfg;
	int err;
L
Linus Torvalds 已提交
2329

2330 2331 2332 2333 2334
	err = rtm_to_fib6_config(skb, nlh, &cfg);
	if (err < 0)
		return err;

	return ip6_route_del(&cfg);
L
Linus Torvalds 已提交
2335 2336
}

2337
static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
L
Linus Torvalds 已提交
2338
{
2339 2340
	struct fib6_config cfg;
	int err;
L
Linus Torvalds 已提交
2341

2342 2343 2344 2345 2346
	err = rtm_to_fib6_config(skb, nlh, &cfg);
	if (err < 0)
		return err;

	return ip6_route_add(&cfg);
L
Linus Torvalds 已提交
2347 2348
}

2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359
static inline size_t rt6_nlmsg_size(void)
{
	return NLMSG_ALIGN(sizeof(struct rtmsg))
	       + nla_total_size(16) /* RTA_SRC */
	       + nla_total_size(16) /* RTA_DST */
	       + nla_total_size(16) /* RTA_GATEWAY */
	       + nla_total_size(16) /* RTA_PREFSRC */
	       + nla_total_size(4) /* RTA_TABLE */
	       + nla_total_size(4) /* RTA_IIF */
	       + nla_total_size(4) /* RTA_OIF */
	       + nla_total_size(4) /* RTA_PRIORITY */
2360
	       + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2361 2362 2363
	       + nla_total_size(sizeof(struct rta_cacheinfo));
}

2364 2365
static int rt6_fill_node(struct net *net,
			 struct sk_buff *skb, struct rt6_info *rt,
2366 2367
			 struct in6_addr *dst, struct in6_addr *src,
			 int iif, int type, u32 pid, u32 seq,
2368
			 int prefix, int nowait, unsigned int flags)
L
Linus Torvalds 已提交
2369 2370
{
	struct rtmsg *rtm;
2371
	struct nlmsghdr *nlh;
2372
	long expires;
2373
	u32 table;
2374
	struct neighbour *n;
L
Linus Torvalds 已提交
2375 2376 2377 2378 2379 2380 2381 2382

	if (prefix) {	/* user wants prefix routes only */
		if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
			/* success since this is not a prefix route */
			return 1;
		}
	}

2383
	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
2384
	if (!nlh)
2385
		return -EMSGSIZE;
2386 2387

	rtm = nlmsg_data(nlh);
L
Linus Torvalds 已提交
2388 2389 2390 2391
	rtm->rtm_family = AF_INET6;
	rtm->rtm_dst_len = rt->rt6i_dst.plen;
	rtm->rtm_src_len = rt->rt6i_src.plen;
	rtm->rtm_tos = 0;
T
Thomas Graf 已提交
2392
	if (rt->rt6i_table)
2393
		table = rt->rt6i_table->tb6_id;
T
Thomas Graf 已提交
2394
	else
2395 2396
		table = RT6_TABLE_UNSPEC;
	rtm->rtm_table = table;
D
David S. Miller 已提交
2397 2398
	if (nla_put_u32(skb, RTA_TABLE, table))
		goto nla_put_failure;
2399
	if (rt->rt6i_flags & RTF_REJECT)
L
Linus Torvalds 已提交
2400
		rtm->rtm_type = RTN_UNREACHABLE;
2401
	else if (rt->rt6i_flags & RTF_LOCAL)
2402
		rtm->rtm_type = RTN_LOCAL;
2403
	else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
L
Linus Torvalds 已提交
2404 2405 2406 2407 2408 2409
		rtm->rtm_type = RTN_LOCAL;
	else
		rtm->rtm_type = RTN_UNICAST;
	rtm->rtm_flags = 0;
	rtm->rtm_scope = RT_SCOPE_UNIVERSE;
	rtm->rtm_protocol = rt->rt6i_protocol;
2410
	if (rt->rt6i_flags & RTF_DYNAMIC)
L
Linus Torvalds 已提交
2411
		rtm->rtm_protocol = RTPROT_REDIRECT;
2412 2413 2414 2415 2416 2417
	else if (rt->rt6i_flags & RTF_ADDRCONF) {
		if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
			rtm->rtm_protocol = RTPROT_RA;
		else
			rtm->rtm_protocol = RTPROT_KERNEL;
	}
L
Linus Torvalds 已提交
2418

2419
	if (rt->rt6i_flags & RTF_CACHE)
L
Linus Torvalds 已提交
2420 2421 2422
		rtm->rtm_flags |= RTM_F_CLONED;

	if (dst) {
D
David S. Miller 已提交
2423 2424
		if (nla_put(skb, RTA_DST, 16, dst))
			goto nla_put_failure;
2425
		rtm->rtm_dst_len = 128;
L
Linus Torvalds 已提交
2426
	} else if (rtm->rtm_dst_len)
D
David S. Miller 已提交
2427 2428
		if (nla_put(skb, RTA_DST, 16, &rt->rt6i_dst.addr))
			goto nla_put_failure;
L
Linus Torvalds 已提交
2429 2430
#ifdef CONFIG_IPV6_SUBTREES
	if (src) {
D
David S. Miller 已提交
2431 2432
		if (nla_put(skb, RTA_SRC, 16, src))
			goto nla_put_failure;
2433
		rtm->rtm_src_len = 128;
D
David S. Miller 已提交
2434 2435 2436
	} else if (rtm->rtm_src_len &&
		   nla_put(skb, RTA_SRC, 16, &rt->rt6i_src.addr))
		goto nla_put_failure;
L
Linus Torvalds 已提交
2437
#endif
2438 2439 2440
	if (iif) {
#ifdef CONFIG_IPV6_MROUTE
		if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
2441
			int err = ip6mr_get_route(net, skb, rtm, nowait);
2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453
			if (err <= 0) {
				if (!nowait) {
					if (err == 0)
						return 0;
					goto nla_put_failure;
				} else {
					if (err == -EMSGSIZE)
						goto nla_put_failure;
				}
			}
		} else
#endif
D
David S. Miller 已提交
2454 2455
			if (nla_put_u32(skb, RTA_IIF, iif))
				goto nla_put_failure;
2456
	} else if (dst) {
L
Linus Torvalds 已提交
2457
		struct in6_addr saddr_buf;
D
David S. Miller 已提交
2458 2459 2460
		if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
		    nla_put(skb, RTA_PREFSRC, 16, &saddr_buf))
			goto nla_put_failure;
L
Linus Torvalds 已提交
2461
	}
2462

2463 2464
	if (rt->rt6i_prefsrc.plen) {
		struct in6_addr saddr_buf;
A
Alexey Dobriyan 已提交
2465
		saddr_buf = rt->rt6i_prefsrc.addr;
D
David S. Miller 已提交
2466 2467
		if (nla_put(skb, RTA_PREFSRC, 16, &saddr_buf))
			goto nla_put_failure;
2468 2469
	}

2470
	if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
2471 2472
		goto nla_put_failure;

2473
	rcu_read_lock();
2474
	n = rt->n;
2475 2476 2477 2478 2479 2480
	if (n) {
		if (nla_put(skb, RTA_GATEWAY, 16, &n->primary_key) < 0) {
			rcu_read_unlock();
			goto nla_put_failure;
		}
	}
2481
	rcu_read_unlock();
2482

D
David S. Miller 已提交
2483 2484 2485 2486 2487
	if (rt->dst.dev &&
	    nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
		goto nla_put_failure;
	if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
		goto nla_put_failure;
2488 2489

	expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
2490

2491
	if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
2492
		goto nla_put_failure;
2493 2494 2495 2496

	return nlmsg_end(skb, nlh);

nla_put_failure:
2497 2498
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
L
Linus Torvalds 已提交
2499 2500
}

2501
int rt6_dump_route(struct rt6_info *rt, void *p_arg)
L
Linus Torvalds 已提交
2502 2503 2504 2505
{
	struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
	int prefix;

2506 2507
	if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
		struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
L
Linus Torvalds 已提交
2508 2509 2510 2511
		prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
	} else
		prefix = 0;

2512 2513
	return rt6_fill_node(arg->net,
		     arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
L
Linus Torvalds 已提交
2514
		     NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2515
		     prefix, 0, NLM_F_MULTI);
L
Linus Torvalds 已提交
2516 2517
}

2518
static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
L
Linus Torvalds 已提交
2519
{
2520
	struct net *net = sock_net(in_skb->sk);
2521 2522
	struct nlattr *tb[RTA_MAX+1];
	struct rt6_info *rt;
L
Linus Torvalds 已提交
2523
	struct sk_buff *skb;
2524
	struct rtmsg *rtm;
2525
	struct flowi6 fl6;
2526
	int err, iif = 0, oif = 0;
L
Linus Torvalds 已提交
2527

2528 2529 2530
	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
	if (err < 0)
		goto errout;
L
Linus Torvalds 已提交
2531

2532
	err = -EINVAL;
2533
	memset(&fl6, 0, sizeof(fl6));
L
Linus Torvalds 已提交
2534

2535 2536 2537 2538
	if (tb[RTA_SRC]) {
		if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
			goto errout;

A
Alexey Dobriyan 已提交
2539
		fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
2540 2541 2542 2543 2544 2545
	}

	if (tb[RTA_DST]) {
		if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
			goto errout;

A
Alexey Dobriyan 已提交
2546
		fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
2547 2548 2549 2550 2551 2552
	}

	if (tb[RTA_IIF])
		iif = nla_get_u32(tb[RTA_IIF]);

	if (tb[RTA_OIF])
2553
		oif = nla_get_u32(tb[RTA_OIF]);
L
Linus Torvalds 已提交
2554 2555 2556

	if (iif) {
		struct net_device *dev;
2557 2558
		int flags = 0;

2559
		dev = __dev_get_by_index(net, iif);
L
Linus Torvalds 已提交
2560 2561
		if (!dev) {
			err = -ENODEV;
2562
			goto errout;
L
Linus Torvalds 已提交
2563
		}
2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575

		fl6.flowi6_iif = iif;

		if (!ipv6_addr_any(&fl6.saddr))
			flags |= RT6_LOOKUP_F_HAS_SADDR;

		rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
							       flags);
	} else {
		fl6.flowi6_oif = oif;

		rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
L
Linus Torvalds 已提交
2576 2577
	}

2578
	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2579
	if (!skb) {
2580
		dst_release(&rt->dst);
2581 2582 2583
		err = -ENOBUFS;
		goto errout;
	}
L
Linus Torvalds 已提交
2584

2585 2586 2587
	/* Reserve room for dummy headers, this skb can pass
	   through good chunk of routing engine.
	 */
2588
	skb_reset_mac_header(skb);
2589
	skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
L
Linus Torvalds 已提交
2590

2591
	skb_dst_set(skb, &rt->dst);
L
Linus Torvalds 已提交
2592

2593
	err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
L
Linus Torvalds 已提交
2594
			    RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2595
			    nlh->nlmsg_seq, 0, 0, 0);
L
Linus Torvalds 已提交
2596
	if (err < 0) {
2597 2598
		kfree_skb(skb);
		goto errout;
L
Linus Torvalds 已提交
2599 2600
	}

2601
	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2602
errout:
L
Linus Torvalds 已提交
2603 2604 2605
	return err;
}

2606
void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
L
Linus Torvalds 已提交
2607 2608
{
	struct sk_buff *skb;
2609
	struct net *net = info->nl_net;
2610 2611 2612 2613
	u32 seq;
	int err;

	err = -ENOBUFS;
2614
	seq = info->nlh ? info->nlh->nlmsg_seq : 0;
2615

2616
	skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2617
	if (!skb)
2618 2619
		goto errout;

2620
	err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
2621
				event, info->pid, seq, 0, 0, 0);
2622 2623 2624 2625 2626 2627
	if (err < 0) {
		/* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(skb);
		goto errout;
	}
2628 2629 2630
	rtnl_notify(skb, net, info->pid, RTNLGRP_IPV6_ROUTE,
		    info->nlh, gfp_any());
	return;
2631 2632
errout:
	if (err < 0)
2633
		rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
L
Linus Torvalds 已提交
2634 2635
}

2636 2637 2638 2639
static int ip6_route_dev_notify(struct notifier_block *this,
				unsigned long event, void *data)
{
	struct net_device *dev = (struct net_device *)data;
2640
	struct net *net = dev_net(dev);
2641 2642

	if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
2643
		net->ipv6.ip6_null_entry->dst.dev = dev;
2644 2645
		net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
2646
		net->ipv6.ip6_prohibit_entry->dst.dev = dev;
2647
		net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
2648
		net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
2649 2650 2651 2652 2653 2654 2655
		net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
#endif
	}

	return NOTIFY_OK;
}

L
Linus Torvalds 已提交
2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672
/*
 *	/proc
 */

#ifdef CONFIG_PROC_FS

struct rt6_proc_arg
{
	char *buffer;
	int offset;
	int length;
	int skip;
	int len;
};

static int rt6_info_route(struct rt6_info *rt, void *p_arg)
{
2673
	struct seq_file *m = p_arg;
2674
	struct neighbour *n;
L
Linus Torvalds 已提交
2675

2676
	seq_printf(m, "%pi6 %02x ", &rt->rt6i_dst.addr, rt->rt6i_dst.plen);
L
Linus Torvalds 已提交
2677 2678

#ifdef CONFIG_IPV6_SUBTREES
2679
	seq_printf(m, "%pi6 %02x ", &rt->rt6i_src.addr, rt->rt6i_src.plen);
L
Linus Torvalds 已提交
2680
#else
2681
	seq_puts(m, "00000000000000000000000000000000 00 ");
L
Linus Torvalds 已提交
2682
#endif
2683
	rcu_read_lock();
2684
	n = rt->n;
2685 2686
	if (n) {
		seq_printf(m, "%pi6", n->primary_key);
L
Linus Torvalds 已提交
2687
	} else {
2688
		seq_puts(m, "00000000000000000000000000000000");
L
Linus Torvalds 已提交
2689
	}
2690
	rcu_read_unlock();
2691
	seq_printf(m, " %08x %08x %08x %08x %8s\n",
2692 2693
		   rt->rt6i_metric, atomic_read(&rt->dst.__refcnt),
		   rt->dst.__use, rt->rt6i_flags,
2694
		   rt->dst.dev ? rt->dst.dev->name : "");
L
Linus Torvalds 已提交
2695 2696 2697
	return 0;
}

2698
static int ipv6_route_show(struct seq_file *m, void *v)
L
Linus Torvalds 已提交
2699
{
2700
	struct net *net = (struct net *)m->private;
2701
	fib6_clean_all_ro(net, rt6_info_route, 0, m);
2702 2703
	return 0;
}
L
Linus Torvalds 已提交
2704

2705 2706
static int ipv6_route_open(struct inode *inode, struct file *file)
{
2707
	return single_open_net(inode, file, ipv6_route_show);
2708 2709
}

2710 2711 2712 2713 2714
static const struct file_operations ipv6_route_proc_fops = {
	.owner		= THIS_MODULE,
	.open		= ipv6_route_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
2715
	.release	= single_release_net,
2716 2717
};

L
Linus Torvalds 已提交
2718 2719
static int rt6_stats_seq_show(struct seq_file *seq, void *v)
{
2720
	struct net *net = (struct net *)seq->private;
L
Linus Torvalds 已提交
2721
	seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2722 2723 2724 2725 2726
		   net->ipv6.rt6_stats->fib_nodes,
		   net->ipv6.rt6_stats->fib_route_nodes,
		   net->ipv6.rt6_stats->fib_rt_alloc,
		   net->ipv6.rt6_stats->fib_rt_entries,
		   net->ipv6.rt6_stats->fib_rt_cache,
2727
		   dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
2728
		   net->ipv6.rt6_stats->fib_discarded_routes);
L
Linus Torvalds 已提交
2729 2730 2731 2732 2733 2734

	return 0;
}

static int rt6_stats_seq_open(struct inode *inode, struct file *file)
{
2735
	return single_open_net(inode, file, rt6_stats_seq_show);
2736 2737
}

2738
static const struct file_operations rt6_stats_seq_fops = {
L
Linus Torvalds 已提交
2739 2740 2741 2742
	.owner	 = THIS_MODULE,
	.open	 = rt6_stats_seq_open,
	.read	 = seq_read,
	.llseek	 = seq_lseek,
2743
	.release = single_release_net,
L
Linus Torvalds 已提交
2744 2745 2746 2747 2748 2749
};
#endif	/* CONFIG_PROC_FS */

#ifdef CONFIG_SYSCTL

static
2750
int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write,
L
Linus Torvalds 已提交
2751 2752
			      void __user *buffer, size_t *lenp, loff_t *ppos)
{
2753 2754 2755
	struct net *net;
	int delay;
	if (!write)
L
Linus Torvalds 已提交
2756
		return -EINVAL;
2757 2758 2759 2760 2761 2762

	net = (struct net *)ctl->extra1;
	delay = net->ipv6.sysctl.flush_delay;
	proc_dointvec(ctl, write, buffer, lenp, ppos);
	fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay, net);
	return 0;
L
Linus Torvalds 已提交
2763 2764
}

2765
ctl_table ipv6_route_table_template[] = {
2766
	{
L
Linus Torvalds 已提交
2767
		.procname	=	"flush",
2768
		.data		=	&init_net.ipv6.sysctl.flush_delay,
L
Linus Torvalds 已提交
2769
		.maxlen		=	sizeof(int),
2770
		.mode		=	0200,
A
Alexey Dobriyan 已提交
2771
		.proc_handler	=	ipv6_sysctl_rtcache_flush
L
Linus Torvalds 已提交
2772 2773 2774
	},
	{
		.procname	=	"gc_thresh",
2775
		.data		=	&ip6_dst_ops_template.gc_thresh,
L
Linus Torvalds 已提交
2776 2777
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2778
		.proc_handler	=	proc_dointvec,
L
Linus Torvalds 已提交
2779 2780 2781
	},
	{
		.procname	=	"max_size",
2782
		.data		=	&init_net.ipv6.sysctl.ip6_rt_max_size,
L
Linus Torvalds 已提交
2783 2784
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2785
		.proc_handler	=	proc_dointvec,
L
Linus Torvalds 已提交
2786 2787 2788
	},
	{
		.procname	=	"gc_min_interval",
2789
		.data		=	&init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
L
Linus Torvalds 已提交
2790 2791
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2792
		.proc_handler	=	proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2793 2794 2795
	},
	{
		.procname	=	"gc_timeout",
2796
		.data		=	&init_net.ipv6.sysctl.ip6_rt_gc_timeout,
L
Linus Torvalds 已提交
2797 2798
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2799
		.proc_handler	=	proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2800 2801 2802
	},
	{
		.procname	=	"gc_interval",
2803
		.data		=	&init_net.ipv6.sysctl.ip6_rt_gc_interval,
L
Linus Torvalds 已提交
2804 2805
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2806
		.proc_handler	=	proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2807 2808 2809
	},
	{
		.procname	=	"gc_elasticity",
2810
		.data		=	&init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
L
Linus Torvalds 已提交
2811 2812
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2813
		.proc_handler	=	proc_dointvec,
L
Linus Torvalds 已提交
2814 2815 2816
	},
	{
		.procname	=	"mtu_expires",
2817
		.data		=	&init_net.ipv6.sysctl.ip6_rt_mtu_expires,
L
Linus Torvalds 已提交
2818 2819
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2820
		.proc_handler	=	proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2821 2822 2823
	},
	{
		.procname	=	"min_adv_mss",
2824
		.data		=	&init_net.ipv6.sysctl.ip6_rt_min_advmss,
L
Linus Torvalds 已提交
2825 2826
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2827
		.proc_handler	=	proc_dointvec,
L
Linus Torvalds 已提交
2828 2829 2830
	},
	{
		.procname	=	"gc_min_interval_ms",
2831
		.data		=	&init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
L
Linus Torvalds 已提交
2832 2833
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2834
		.proc_handler	=	proc_dointvec_ms_jiffies,
L
Linus Torvalds 已提交
2835
	},
2836
	{ }
L
Linus Torvalds 已提交
2837 2838
};

2839
struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
2840 2841 2842 2843 2844 2845
{
	struct ctl_table *table;

	table = kmemdup(ipv6_route_table_template,
			sizeof(ipv6_route_table_template),
			GFP_KERNEL);
2846 2847 2848

	if (table) {
		table[0].data = &net->ipv6.sysctl.flush_delay;
2849
		table[0].extra1 = net;
2850
		table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
2851 2852 2853 2854 2855 2856 2857
		table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
		table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
		table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
		table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
		table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
		table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
		table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
2858
		table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2859 2860
	}

2861 2862
	return table;
}
L
Linus Torvalds 已提交
2863 2864
#endif

2865
static int __net_init ip6_route_net_init(struct net *net)
2866
{
2867
	int ret = -ENOMEM;
2868

2869 2870
	memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
	       sizeof(net->ipv6.ip6_dst_ops));
2871

2872 2873 2874
	if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
		goto out_ip6_dst_ops;

2875 2876 2877 2878
	net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
					   sizeof(*net->ipv6.ip6_null_entry),
					   GFP_KERNEL);
	if (!net->ipv6.ip6_null_entry)
2879
		goto out_ip6_dst_entries;
2880
	net->ipv6.ip6_null_entry->dst.path =
2881
		(struct dst_entry *)net->ipv6.ip6_null_entry;
2882
	net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2883 2884
	dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
			 ip6_template_metrics, true);
2885 2886 2887 2888 2889

#ifdef CONFIG_IPV6_MULTIPLE_TABLES
	net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
					       sizeof(*net->ipv6.ip6_prohibit_entry),
					       GFP_KERNEL);
2890 2891
	if (!net->ipv6.ip6_prohibit_entry)
		goto out_ip6_null_entry;
2892
	net->ipv6.ip6_prohibit_entry->dst.path =
2893
		(struct dst_entry *)net->ipv6.ip6_prohibit_entry;
2894
	net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2895 2896
	dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
			 ip6_template_metrics, true);
2897 2898 2899 2900

	net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
					       sizeof(*net->ipv6.ip6_blk_hole_entry),
					       GFP_KERNEL);
2901 2902
	if (!net->ipv6.ip6_blk_hole_entry)
		goto out_ip6_prohibit_entry;
2903
	net->ipv6.ip6_blk_hole_entry->dst.path =
2904
		(struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
2905
	net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2906 2907
	dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
			 ip6_template_metrics, true);
2908 2909
#endif

2910 2911 2912 2913 2914 2915 2916 2917 2918
	net->ipv6.sysctl.flush_delay = 0;
	net->ipv6.sysctl.ip6_rt_max_size = 4096;
	net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
	net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
	net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
	net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
	net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
	net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;

2919 2920
	net->ipv6.ip6_rt_gc_expire = 30*HZ;

2921 2922 2923
	ret = 0;
out:
	return ret;
2924

2925 2926 2927 2928 2929 2930
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
out_ip6_prohibit_entry:
	kfree(net->ipv6.ip6_prohibit_entry);
out_ip6_null_entry:
	kfree(net->ipv6.ip6_null_entry);
#endif
2931 2932
out_ip6_dst_entries:
	dst_entries_destroy(&net->ipv6.ip6_dst_ops);
2933 2934
out_ip6_dst_ops:
	goto out;
2935 2936
}

2937
static void __net_exit ip6_route_net_exit(struct net *net)
2938
{
2939 2940 2941 2942 2943
	kfree(net->ipv6.ip6_null_entry);
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
	kfree(net->ipv6.ip6_prohibit_entry);
	kfree(net->ipv6.ip6_blk_hole_entry);
#endif
2944
	dst_entries_destroy(&net->ipv6.ip6_dst_ops);
2945 2946
}

2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963
static int __net_init ip6_route_net_init_late(struct net *net)
{
#ifdef CONFIG_PROC_FS
	proc_net_fops_create(net, "ipv6_route", 0, &ipv6_route_proc_fops);
	proc_net_fops_create(net, "rt6_stats", S_IRUGO, &rt6_stats_seq_fops);
#endif
	return 0;
}

static void __net_exit ip6_route_net_exit_late(struct net *net)
{
#ifdef CONFIG_PROC_FS
	proc_net_remove(net, "ipv6_route");
	proc_net_remove(net, "rt6_stats");
#endif
}

2964 2965 2966 2967 2968
static struct pernet_operations ip6_route_net_ops = {
	.init = ip6_route_net_init,
	.exit = ip6_route_net_exit,
};

2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984
static int __net_init ipv6_inetpeer_init(struct net *net)
{
	struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);

	if (!bp)
		return -ENOMEM;
	inet_peer_base_init(bp);
	net->ipv6.peers = bp;
	return 0;
}

static void __net_exit ipv6_inetpeer_exit(struct net *net)
{
	struct inet_peer_base *bp = net->ipv6.peers;

	net->ipv6.peers = NULL;
2985
	inetpeer_invalidate_tree(bp);
2986 2987 2988
	kfree(bp);
}

2989
static struct pernet_operations ipv6_inetpeer_ops = {
2990 2991 2992 2993
	.init	=	ipv6_inetpeer_init,
	.exit	=	ipv6_inetpeer_exit,
};

2994 2995 2996 2997 2998
static struct pernet_operations ip6_route_net_late_ops = {
	.init = ip6_route_net_init_late,
	.exit = ip6_route_net_exit_late,
};

2999 3000 3001 3002 3003
static struct notifier_block ip6_route_dev_notifier = {
	.notifier_call = ip6_route_dev_notify,
	.priority = 0,
};

3004
int __init ip6_route_init(void)
L
Linus Torvalds 已提交
3005
{
3006 3007
	int ret;

3008 3009
	ret = -ENOMEM;
	ip6_dst_ops_template.kmem_cachep =
A
Alexey Dobriyan 已提交
3010
		kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3011
				  SLAB_HWCACHE_ALIGN, NULL);
3012
	if (!ip6_dst_ops_template.kmem_cachep)
3013
		goto out;
3014

3015
	ret = dst_entries_init(&ip6_dst_blackhole_ops);
3016
	if (ret)
3017 3018
		goto out_kmem_cache;

3019 3020
	ret = register_pernet_subsys(&ipv6_inetpeer_ops);
	if (ret)
3021
		goto out_dst_entries;
3022

3023 3024 3025
	ret = register_pernet_subsys(&ip6_route_net_ops);
	if (ret)
		goto out_register_inetpeer;
3026

3027 3028
	ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;

3029 3030 3031
	/* Registering of the loopback is done before this portion of code,
	 * the loopback reference in rt6_info will not be taken, do it
	 * manually for init_net */
3032
	init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3033 3034
	init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
  #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3035
	init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3036
	init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3037
	init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3038 3039
	init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
  #endif
3040
	ret = fib6_init();
3041
	if (ret)
3042
		goto out_register_subsys;
3043 3044 3045

	ret = xfrm6_init();
	if (ret)
3046
		goto out_fib6_init;
3047

3048 3049 3050
	ret = fib6_rules_init();
	if (ret)
		goto xfrm6_init;
3051

3052 3053 3054 3055
	ret = register_pernet_subsys(&ip6_route_net_late_ops);
	if (ret)
		goto fib6_rules_init;

3056
	ret = -ENOBUFS;
3057 3058 3059
	if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
	    __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
	    __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3060
		goto out_register_late_subsys;
3061

3062
	ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3063
	if (ret)
3064
		goto out_register_late_subsys;
3065

3066 3067 3068
out:
	return ret;

3069 3070
out_register_late_subsys:
	unregister_pernet_subsys(&ip6_route_net_late_ops);
3071 3072 3073 3074
fib6_rules_init:
	fib6_rules_cleanup();
xfrm6_init:
	xfrm6_fini();
3075 3076
out_fib6_init:
	fib6_gc_cleanup();
3077 3078
out_register_subsys:
	unregister_pernet_subsys(&ip6_route_net_ops);
3079 3080
out_register_inetpeer:
	unregister_pernet_subsys(&ipv6_inetpeer_ops);
3081 3082
out_dst_entries:
	dst_entries_destroy(&ip6_dst_blackhole_ops);
3083
out_kmem_cache:
3084
	kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3085
	goto out;
L
Linus Torvalds 已提交
3086 3087 3088 3089
}

void ip6_route_cleanup(void)
{
3090
	unregister_netdevice_notifier(&ip6_route_dev_notifier);
3091
	unregister_pernet_subsys(&ip6_route_net_late_ops);
T
Thomas Graf 已提交
3092
	fib6_rules_cleanup();
L
Linus Torvalds 已提交
3093 3094
	xfrm6_fini();
	fib6_gc_cleanup();
3095
	unregister_pernet_subsys(&ipv6_inetpeer_ops);
3096
	unregister_pernet_subsys(&ip6_route_net_ops);
3097
	dst_entries_destroy(&ip6_dst_blackhole_ops);
3098
	kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
L
Linus Torvalds 已提交
3099
}