route.c 69.2 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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#include <linux/capability.h>
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#include <linux/errno.h>
#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

/* Set to 3 to get tracing. */
#define RT6_DEBUG 2

#if RT6_DEBUG >= 3
#define RDBG(x) printk x
#define RT6_TRACE(x...) printk(KERN_DEBUG x)
#else
#define RDBG(x)
#define RT6_TRACE(x...) do { ; } while (0)
#endif

static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
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_default_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);
static void		ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);

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#ifdef CONFIG_IPV6_ROUTE_INFO
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static struct rt6_info *rt6_add_route_info(struct net *net,
					   struct in6_addr *prefix, int prefixlen,
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					   struct in6_addr *gwaddr, int ifindex,
					   unsigned pref);
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static struct rt6_info *rt6_get_route_info(struct net *net,
					   struct in6_addr *prefix, int prefixlen,
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					   struct in6_addr *gwaddr, int ifindex);
#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;

	if (!rt->rt6i_peer)
		rt6_bind_peer(rt, 1);

	peer = rt->rt6i_peer;
	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 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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	.default_mtu		=	ip6_default_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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	.local_out		=	__ip6_local_out,
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};

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static unsigned int ip6_blackhole_default_mtu(const struct dst_entry *dst)
{
	return 0;
}

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static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
{
}

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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	.default_mtu		=	ip6_blackhole_default_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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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 dst_ops *ops)
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{
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	return (struct rt6_info *)dst_alloc(ops, 0);
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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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	struct inet_peer *peer = rt->rt6i_peer;
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	if (idev != NULL) {
		rt->rt6i_idev = NULL;
		in6_dev_put(idev);
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	}
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	if (peer) {
		rt->rt6i_peer = NULL;
		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)
{
	struct inet_peer *peer;

	peer = inet_getpeer_v6(&rt->rt6i_dst.addr, create);
	if (peer && cmpxchg(&rt->rt6i_peer, NULL, peer) != NULL)
		inet_putpeer(peer);
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	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 && idev != NULL && idev->dev == dev) {
		struct inet6_dev *loopback_idev =
			in6_dev_get(loopback_dev);
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		if (loopback_idev != NULL) {
			rt->rt6i_idev = loopback_idev;
			in6_dev_put(idev);
		}
	}
}

static __inline__ int rt6_check_expired(const struct rt6_info *rt)
{
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	return (rt->rt6i_flags & RTF_EXPIRES) &&
		time_after(jiffies, rt->rt6i_expires);
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}

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static inline int rt6_need_strict(struct in6_addr *daddr)
{
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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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						    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->rt6i_dev;

		if (oif) {
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			if (dev->ifindex == oif)
				return sprt;
			if (dev->flags & IFF_LOOPBACK) {
				if (sprt->rt6i_idev == NULL ||
				    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)
{
	struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL;
	/*
	 * 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.
	 */
	if (!neigh || (neigh->nud_state & NUD_VALID))
		return;
	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);
		ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL);
	} else
		read_unlock_bh(&neigh->lock);
}
#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)
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{
	struct net_device *dev = rt->rt6i_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 = rt->rt6i_nexthop;
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	int m;
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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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	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)
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{
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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;
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	int mpri = -1;
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	match = NULL;
	for (rt = rr_head; rt && rt->rt6i_metric == metric;
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	     rt = rt->dst.rt6_next)
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		match = find_match(rt, oif, strict, &mpri, match);
	for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
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	     rt = rt->dst.rt6_next)
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		match = find_match(rt, oif, strict, &mpri, match);
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	return match;
}
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static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
{
	struct rt6_info *match, *rt0;
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	struct net *net;
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	RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n",
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		  __func__, fn->leaf, oif);
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	rt0 = fn->rr_ptr;
	if (!rt0)
		fn->rr_ptr = rt0 = fn->leaf;
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	match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict);
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	if (!match &&
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	    (strict & RT6_LOOKUP_F_REACHABLE)) {
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		struct rt6_info *next = rt0->dst.rt6_next;
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		/* no entries matched; do round-robin */
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		if (!next || next->rt6i_metric != rt0->rt6i_metric)
			next = fn->leaf;

		if (next != rt0)
			fn->rr_ptr = next;
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	}

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	RT6_TRACE("%s() => %p\n",
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		  __func__, match);
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	net = dev_net(rt0->rt6i_dev);
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	return match ? match : net->ipv6.ip6_null_entry;
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}

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#ifdef CONFIG_IPV6_ROUTE_INFO
int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
		  struct in6_addr *gwaddr)
{
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	struct net *net = dev_net(dev);
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	struct route_info *rinfo = (struct route_info *) opt;
	struct in6_addr prefix_buf, *prefix;
	unsigned int pref;
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	unsigned long lifetime;
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	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)
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		return -EINVAL;
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	lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
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	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;
	}

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	rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, gwaddr,
				dev->ifindex);
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	if (rt && !lifetime) {
558
		ip6_del_rt(rt);
559 560 561 562
		rt = NULL;
	}

	if (!rt && lifetime)
563
		rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
564 565 566 567 568 569
					pref);
	else if (rt)
		rt->rt6i_flags = RTF_ROUTEINFO |
				 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);

	if (rt) {
570
		if (!addrconf_finite_timeout(lifetime)) {
571 572 573 574 575
			rt->rt6i_flags &= ~RTF_EXPIRES;
		} else {
			rt->rt6i_expires = jiffies + HZ * lifetime;
			rt->rt6i_flags |= RTF_EXPIRES;
		}
576
		dst_release(&rt->dst);
577 578 579 580 581
	}
	return 0;
}
#endif

582
#define BACKTRACK(__net, saddr)			\
583
do { \
584
	if (rt == __net->ipv6.ip6_null_entry) {	\
585
		struct fib6_node *pn; \
V
Ville Nuorvala 已提交
586
		while (1) { \
587 588 589 590
			if (fn->fn_flags & RTN_TL_ROOT) \
				goto out; \
			pn = fn->parent; \
			if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
591
				fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
592 593 594 595
			else \
				fn = pn; \
			if (fn->fn_flags & RTN_RTINFO) \
				goto restart; \
T
Thomas Graf 已提交
596 597
		} \
	} \
598
} while(0)
T
Thomas Graf 已提交
599

600 601
static struct rt6_info *ip6_pol_route_lookup(struct net *net,
					     struct fib6_table *table,
T
Thomas Graf 已提交
602
					     struct flowi *fl, int flags)
L
Linus Torvalds 已提交
603 604 605 606
{
	struct fib6_node *fn;
	struct rt6_info *rt;

T
Thomas Graf 已提交
607 608 609 610
	read_lock_bh(&table->tb6_lock);
	fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
restart:
	rt = fn->leaf;
611
	rt = rt6_device_match(net, rt, &fl->fl6_src, fl->oif, flags);
612
	BACKTRACK(net, &fl->fl6_src);
T
Thomas Graf 已提交
613
out:
614
	dst_use(&rt->dst, jiffies);
T
Thomas Graf 已提交
615 616 617 618 619
	read_unlock_bh(&table->tb6_lock);
	return rt;

}

620 621
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
622 623 624
{
	struct flowi fl = {
		.oif = oif,
625
		.fl6_dst = *daddr,
T
Thomas Graf 已提交
626 627
	};
	struct dst_entry *dst;
628
	int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
T
Thomas Graf 已提交
629

630 631 632 633 634
	if (saddr) {
		memcpy(&fl.fl6_src, saddr, sizeof(*saddr));
		flags |= RT6_LOOKUP_F_HAS_SADDR;
	}

635
	dst = fib6_rule_lookup(net, &fl, flags, ip6_pol_route_lookup);
T
Thomas Graf 已提交
636 637 638 639 640
	if (dst->error == 0)
		return (struct rt6_info *) dst;

	dst_release(dst);

L
Linus Torvalds 已提交
641 642 643
	return NULL;
}

644 645
EXPORT_SYMBOL(rt6_lookup);

T
Thomas Graf 已提交
646
/* ip6_ins_rt is called with FREE table->tb6_lock.
L
Linus Torvalds 已提交
647 648 649 650 651
   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.
 */

652
static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
L
Linus Torvalds 已提交
653 654
{
	int err;
T
Thomas Graf 已提交
655
	struct fib6_table *table;
L
Linus Torvalds 已提交
656

T
Thomas Graf 已提交
657 658
	table = rt->rt6i_table;
	write_lock_bh(&table->tb6_lock);
659
	err = fib6_add(&table->tb6_root, rt, info);
T
Thomas Graf 已提交
660
	write_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
661 662 663 664

	return err;
}

665 666
int ip6_ins_rt(struct rt6_info *rt)
{
667
	struct nl_info info = {
668
		.nl_net = dev_net(rt->rt6i_dev),
669
	};
670
	return __ip6_ins_rt(rt, &info);
671 672
}

673 674
static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, struct in6_addr *daddr,
				      struct in6_addr *saddr)
L
Linus Torvalds 已提交
675 676 677 678 679 680 681 682 683 684
{
	struct rt6_info *rt;

	/*
	 *	Clone the route.
	 */

	rt = ip6_rt_copy(ort);

	if (rt) {
685 686 687
		struct neighbour *neigh;
		int attempts = !in_softirq();

688 689 690 691
		if (!(rt->rt6i_flags&RTF_GATEWAY)) {
			if (rt->rt6i_dst.plen != 128 &&
			    ipv6_addr_equal(&rt->rt6i_dst.addr, daddr))
				rt->rt6i_flags |= RTF_ANYCAST;
L
Linus Torvalds 已提交
692
			ipv6_addr_copy(&rt->rt6i_gateway, daddr);
693
		}
L
Linus Torvalds 已提交
694

695
		ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
L
Linus Torvalds 已提交
696 697
		rt->rt6i_dst.plen = 128;
		rt->rt6i_flags |= RTF_CACHE;
698
		rt->dst.flags |= DST_HOST;
L
Linus Torvalds 已提交
699 700 701 702 703 704 705 706

#ifdef CONFIG_IPV6_SUBTREES
		if (rt->rt6i_src.plen && saddr) {
			ipv6_addr_copy(&rt->rt6i_src.addr, saddr);
			rt->rt6i_src.plen = 128;
		}
#endif

707 708 709 710 711 712 713 714 715 716 717 718 719
	retry:
		neigh = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
		if (IS_ERR(neigh)) {
			struct net *net = dev_net(rt->rt6i_dev);
			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;

720
				ip6_dst_gc(&net->ipv6.ip6_dst_ops);
721 722 723 724 725 726 727 728 729 730

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

			if (net_ratelimit())
				printk(KERN_WARNING
731
				       "ipv6: Neighbour table overflow.\n");
732
			dst_free(&rt->dst);
733 734 735
			return NULL;
		}
		rt->rt6i_nexthop = neigh;
L
Linus Torvalds 已提交
736

737
	}
L
Linus Torvalds 已提交
738

739 740
	return rt;
}
L
Linus Torvalds 已提交
741

742 743 744 745 746 747 748
static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, struct in6_addr *daddr)
{
	struct rt6_info *rt = ip6_rt_copy(ort);
	if (rt) {
		ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
		rt->rt6i_dst.plen = 128;
		rt->rt6i_flags |= RTF_CACHE;
749
		rt->dst.flags |= DST_HOST;
750 751 752 753 754
		rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop);
	}
	return rt;
}

755 756
static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
				      struct flowi *fl, int flags)
L
Linus Torvalds 已提交
757 758
{
	struct fib6_node *fn;
759
	struct rt6_info *rt, *nrt;
T
Thomas Graf 已提交
760
	int strict = 0;
L
Linus Torvalds 已提交
761
	int attempts = 3;
762
	int err;
763
	int reachable = net->ipv6.devconf_all->forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
L
Linus Torvalds 已提交
764

765
	strict |= flags & RT6_LOOKUP_F_IFACE;
L
Linus Torvalds 已提交
766 767

relookup:
T
Thomas Graf 已提交
768
	read_lock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
769

770
restart_2:
T
Thomas Graf 已提交
771
	fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
L
Linus Torvalds 已提交
772 773

restart:
774
	rt = rt6_select(fn, oif, strict | reachable);
775 776 777

	BACKTRACK(net, &fl->fl6_src);
	if (rt == net->ipv6.ip6_null_entry ||
778
	    rt->rt6i_flags & RTF_CACHE)
779
		goto out;
L
Linus Torvalds 已提交
780

781
	dst_hold(&rt->dst);
T
Thomas Graf 已提交
782
	read_unlock_bh(&table->tb6_lock);
783

784
	if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
T
Thomas Graf 已提交
785
		nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
786
	else
T
Thomas Graf 已提交
787
		nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
788

789
	dst_release(&rt->dst);
790
	rt = nrt ? : net->ipv6.ip6_null_entry;
L
Linus Torvalds 已提交
791

792
	dst_hold(&rt->dst);
793
	if (nrt) {
794
		err = ip6_ins_rt(nrt);
795
		if (!err)
L
Linus Torvalds 已提交
796 797 798
			goto out2;
	}

799 800 801 802
	if (--attempts <= 0)
		goto out2;

	/*
T
Thomas Graf 已提交
803
	 * Race condition! In the gap, when table->tb6_lock was
804 805
	 * released someone could insert this route.  Relookup.
	 */
806
	dst_release(&rt->dst);
807 808 809
	goto relookup;

out:
810 811 812 813
	if (reachable) {
		reachable = 0;
		goto restart_2;
	}
814
	dst_hold(&rt->dst);
T
Thomas Graf 已提交
815
	read_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
816
out2:
817 818
	rt->dst.lastuse = jiffies;
	rt->dst.__use++;
T
Thomas Graf 已提交
819 820

	return rt;
L
Linus Torvalds 已提交
821 822
}

823
static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
824 825
					    struct flowi *fl, int flags)
{
826
	return ip6_pol_route(net, table, fl->iif, fl, flags);
827 828
}

T
Thomas Graf 已提交
829 830
void ip6_route_input(struct sk_buff *skb)
{
831
	struct ipv6hdr *iph = ipv6_hdr(skb);
832
	struct net *net = dev_net(skb->dev);
833
	int flags = RT6_LOOKUP_F_HAS_SADDR;
T
Thomas Graf 已提交
834 835
	struct flowi fl = {
		.iif = skb->dev->ifindex,
836 837 838
		.fl6_dst = iph->daddr,
		.fl6_src = iph->saddr,
		.fl6_flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK,
839
		.mark = skb->mark,
T
Thomas Graf 已提交
840 841
		.proto = iph->nexthdr,
	};
842

T
Thomas Goff 已提交
843
	if (rt6_need_strict(&iph->daddr) && skb->dev->type != ARPHRD_PIMREG)
844
		flags |= RT6_LOOKUP_F_IFACE;
T
Thomas Graf 已提交
845

E
Eric Dumazet 已提交
846
	skb_dst_set(skb, fib6_rule_lookup(net, &fl, flags, ip6_pol_route_input));
T
Thomas Graf 已提交
847 848
}

849
static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
T
Thomas Graf 已提交
850
					     struct flowi *fl, int flags)
L
Linus Torvalds 已提交
851
{
852
	return ip6_pol_route(net, table, fl->oif, fl, flags);
T
Thomas Graf 已提交
853 854
}

855 856
struct dst_entry * ip6_route_output(struct net *net, struct sock *sk,
				    struct flowi *fl)
T
Thomas Graf 已提交
857 858 859
{
	int flags = 0;

B
Brian Haley 已提交
860
	if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl->fl6_dst))
861
		flags |= RT6_LOOKUP_F_IFACE;
T
Thomas Graf 已提交
862

863 864
	if (!ipv6_addr_any(&fl->fl6_src))
		flags |= RT6_LOOKUP_F_HAS_SADDR;
865 866
	else if (sk)
		flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
867

868
	return fib6_rule_lookup(net, fl, flags, ip6_pol_route_output);
L
Linus Torvalds 已提交
869 870
}

871
EXPORT_SYMBOL(ip6_route_output);
L
Linus Torvalds 已提交
872

873
struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
874
{
875 876
	struct rt6_info *rt = dst_alloc(&ip6_dst_blackhole_ops, 1);
	struct rt6_info *ort = (struct rt6_info *) dst_orig;
877 878 879
	struct dst_entry *new = NULL;

	if (rt) {
880
		new = &rt->dst;
881 882

		new->__use = 1;
883 884
		new->input = dst_discard;
		new->output = dst_discard;
885

886
		dst_copy_metrics(new, &ort->dst);
887
		new->dev = ort->dst.dev;
888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906
		if (new->dev)
			dev_hold(new->dev);
		rt->rt6i_idev = ort->rt6i_idev;
		if (rt->rt6i_idev)
			in6_dev_hold(rt->rt6i_idev);
		rt->rt6i_expires = 0;

		ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
		rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
		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);
	}

907 908
	dst_release(dst_orig);
	return new ? new : ERR_PTR(-ENOMEM);
909 910
}

L
Linus Torvalds 已提交
911 912 913 914 915 916 917 918 919 920
/*
 *	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;

921 922 923 924 925 926
	if (rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie)) {
		if (rt->rt6i_peer_genid != rt6_peer_genid()) {
			if (!rt->rt6i_peer)
				rt6_bind_peer(rt, 0);
			rt->rt6i_peer_genid = rt6_peer_genid();
		}
L
Linus Torvalds 已提交
927
		return dst;
928
	}
L
Linus Torvalds 已提交
929 930 931 932 933 934 935 936
	return NULL;
}

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

	if (rt) {
937 938 939 940 941 942
		if (rt->rt6i_flags & RTF_CACHE) {
			if (rt6_check_expired(rt)) {
				ip6_del_rt(rt);
				dst = NULL;
			}
		} else {
L
Linus Torvalds 已提交
943
			dst_release(dst);
944 945
			dst = NULL;
		}
L
Linus Torvalds 已提交
946
	}
947
	return dst;
L
Linus Torvalds 已提交
948 949 950 951 952 953
}

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

954
	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
L
Linus Torvalds 已提交
955

E
Eric Dumazet 已提交
956
	rt = (struct rt6_info *) skb_dst(skb);
L
Linus Torvalds 已提交
957 958
	if (rt) {
		if (rt->rt6i_flags&RTF_CACHE) {
959
			dst_set_expires(&rt->dst, 0);
L
Linus Torvalds 已提交
960 961 962 963 964 965 966 967 968 969 970 971 972
			rt->rt6i_flags |= RTF_EXPIRES;
		} else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
			rt->rt6i_node->fn_sernum = -1;
	}
}

static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
{
	struct rt6_info *rt6 = (struct rt6_info*)dst;

	if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
		rt6->rt6i_flags |= RTF_MODIFIED;
		if (mtu < IPV6_MIN_MTU) {
973
			u32 features = dst_metric(dst, RTAX_FEATURES);
L
Linus Torvalds 已提交
974
			mtu = IPV6_MIN_MTU;
975 976
			features |= RTAX_FEATURE_ALLFRAG;
			dst_metric_set(dst, RTAX_FEATURES, features);
L
Linus Torvalds 已提交
977
		}
978
		dst_metric_set(dst, RTAX_MTU, mtu);
L
Linus Torvalds 已提交
979 980 981
	}
}

982
static unsigned int ip6_default_advmss(const struct dst_entry *dst)
L
Linus Torvalds 已提交
983
{
984 985 986 987
	struct net_device *dev = dst->dev;
	unsigned int mtu = dst_mtu(dst);
	struct net *net = dev_net(dev);

L
Linus Torvalds 已提交
988 989
	mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);

990 991
	if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
		mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
L
Linus Torvalds 已提交
992 993

	/*
994 995 996
	 * 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
997 998 999 1000 1001 1002 1003
	 * rely only on pmtu discovery"
	 */
	if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
		mtu = IPV6_MAXPLEN;
	return mtu;
}

1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017
static unsigned int ip6_default_mtu(const struct dst_entry *dst)
{
	unsigned int mtu = IPV6_MIN_MTU;
	struct inet6_dev *idev;

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

	return mtu;
}

1018 1019
static struct dst_entry *icmp6_dst_gc_list;
static DEFINE_SPINLOCK(icmp6_dst_lock);
1020

1021
struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
L
Linus Torvalds 已提交
1022
				  struct neighbour *neigh,
1023
				  const struct in6_addr *addr)
L
Linus Torvalds 已提交
1024 1025 1026
{
	struct rt6_info *rt;
	struct inet6_dev *idev = in6_dev_get(dev);
1027
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
1028 1029 1030 1031

	if (unlikely(idev == NULL))
		return NULL;

1032
	rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
L
Linus Torvalds 已提交
1033 1034 1035 1036 1037 1038 1039 1040
	if (unlikely(rt == NULL)) {
		in6_dev_put(idev);
		goto out;
	}

	dev_hold(dev);
	if (neigh)
		neigh_hold(neigh);
1041
	else {
L
Linus Torvalds 已提交
1042
		neigh = ndisc_get_neigh(dev, addr);
1043 1044 1045
		if (IS_ERR(neigh))
			neigh = NULL;
	}
L
Linus Torvalds 已提交
1046 1047 1048 1049

	rt->rt6i_dev	  = dev;
	rt->rt6i_idev     = idev;
	rt->rt6i_nexthop  = neigh;
1050
	atomic_set(&rt->dst.__refcnt, 1);
1051
	dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 255);
1052
	rt->dst.output  = ip6_output;
L
Linus Torvalds 已提交
1053 1054

#if 0	/* there's no chance to use these for ndisc */
1055
	rt->dst.flags   = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST
1056
				? DST_HOST
L
Linus Torvalds 已提交
1057 1058 1059 1060 1061
				: 0;
	ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
	rt->rt6i_dst.plen = 128;
#endif

1062
	spin_lock_bh(&icmp6_dst_lock);
1063 1064
	rt->dst.next = icmp6_dst_gc_list;
	icmp6_dst_gc_list = &rt->dst;
1065
	spin_unlock_bh(&icmp6_dst_lock);
L
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1066

1067
	fib6_force_start_gc(net);
L
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1068 1069

out:
1070
	return &rt->dst;
L
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1071 1072
}

1073
int icmp6_dst_gc(void)
L
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1074
{
1075
	struct dst_entry *dst, **pprev;
1076
	int more = 0;
L
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1077

1078 1079
	spin_lock_bh(&icmp6_dst_lock);
	pprev = &icmp6_dst_gc_list;
1080

L
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1081 1082 1083 1084 1085 1086
	while ((dst = *pprev) != NULL) {
		if (!atomic_read(&dst->__refcnt)) {
			*pprev = dst->next;
			dst_free(dst);
		} else {
			pprev = &dst->next;
1087
			++more;
L
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1088 1089 1090
		}
	}

1091
	spin_unlock_bh(&icmp6_dst_lock);
1092

1093
	return more;
L
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1094 1095
}

1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114
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);
}

1115
static int ip6_dst_gc(struct dst_ops *ops)
L
Linus Torvalds 已提交
1116 1117
{
	unsigned long now = jiffies;
1118
	struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1119 1120 1121 1122 1123
	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;
1124
	int entries;
1125

1126
	entries = dst_entries_get_fast(ops);
1127
	if (time_after(rt_last_gc + rt_min_interval, now) &&
1128
	    entries <= rt_max_size)
L
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1129 1130
		goto out;

1131 1132 1133
	net->ipv6.ip6_rt_gc_expire++;
	fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net);
	net->ipv6.ip6_rt_last_gc = now;
1134 1135
	entries = dst_entries_get_slow(ops);
	if (entries < ops->gc_thresh)
1136
		net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
L
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1137
out:
1138
	net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1139
	return entries > rt_max_size;
L
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1140 1141 1142 1143 1144 1145 1146 1147
}

/* 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!
 */

1148
int ip6_dst_hoplimit(struct dst_entry *dst)
L
Linus Torvalds 已提交
1149
{
1150
	int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
1151
	if (hoplimit == 0) {
1152
		struct net_device *dev = dst->dev;
1153 1154 1155 1156 1157
		struct inet6_dev *idev;

		rcu_read_lock();
		idev = __in6_dev_get(dev);
		if (idev)
1158
			hoplimit = idev->cnf.hop_limit;
1159
		else
1160
			hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit;
1161
		rcu_read_unlock();
L
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1162 1163 1164
	}
	return hoplimit;
}
1165
EXPORT_SYMBOL(ip6_dst_hoplimit);
L
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1166 1167 1168 1169 1170

/*
 *
 */

1171
int ip6_route_add(struct fib6_config *cfg)
L
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1172 1173
{
	int err;
1174
	struct net *net = cfg->fc_nlinfo.nl_net;
L
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1175 1176 1177
	struct rt6_info *rt = NULL;
	struct net_device *dev = NULL;
	struct inet6_dev *idev = NULL;
T
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1178
	struct fib6_table *table;
L
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1179 1180
	int addr_type;

1181
	if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
L
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1182 1183
		return -EINVAL;
#ifndef CONFIG_IPV6_SUBTREES
1184
	if (cfg->fc_src_len)
L
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1185 1186
		return -EINVAL;
#endif
1187
	if (cfg->fc_ifindex) {
L
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1188
		err = -ENODEV;
1189
		dev = dev_get_by_index(net, cfg->fc_ifindex);
L
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1190 1191 1192 1193 1194 1195 1196
		if (!dev)
			goto out;
		idev = in6_dev_get(dev);
		if (!idev)
			goto out;
	}

1197 1198
	if (cfg->fc_metric == 0)
		cfg->fc_metric = IP6_RT_PRIO_USER;
L
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1199

1200
	table = fib6_new_table(net, cfg->fc_table);
T
Thomas Graf 已提交
1201 1202 1203 1204 1205
	if (table == NULL) {
		err = -ENOBUFS;
		goto out;
	}

1206
	rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
L
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1207 1208 1209 1210 1211 1212

	if (rt == NULL) {
		err = -ENOMEM;
		goto out;
	}

1213
	rt->dst.obsolete = -1;
1214 1215 1216
	rt->rt6i_expires = (cfg->fc_flags & RTF_EXPIRES) ?
				jiffies + clock_t_to_jiffies(cfg->fc_expires) :
				0;
L
Linus Torvalds 已提交
1217

1218 1219 1220 1221 1222
	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
1223 1224

	if (addr_type & IPV6_ADDR_MULTICAST)
1225
		rt->dst.input = ip6_mc_input;
1226 1227
	else if (cfg->fc_flags & RTF_LOCAL)
		rt->dst.input = ip6_input;
L
Linus Torvalds 已提交
1228
	else
1229
		rt->dst.input = ip6_forward;
L
Linus Torvalds 已提交
1230

1231
	rt->dst.output = ip6_output;
L
Linus Torvalds 已提交
1232

1233 1234
	ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
	rt->rt6i_dst.plen = cfg->fc_dst_len;
L
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1235
	if (rt->rt6i_dst.plen == 128)
1236
	       rt->dst.flags = DST_HOST;
L
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1237 1238

#ifdef CONFIG_IPV6_SUBTREES
1239 1240
	ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
	rt->rt6i_src.plen = cfg->fc_src_len;
L
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1241 1242
#endif

1243
	rt->rt6i_metric = cfg->fc_metric;
L
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1244 1245 1246 1247

	/* We cannot add true routes via loopback here,
	   they would result in kernel looping; promote them to reject routes
	 */
1248
	if ((cfg->fc_flags & RTF_REJECT) ||
1249 1250
	    (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK)
					      && !(cfg->fc_flags&RTF_LOCAL))) {
L
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1251
		/* hold loopback dev/idev if we haven't done so. */
1252
		if (dev != net->loopback_dev) {
L
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1253 1254 1255 1256
			if (dev) {
				dev_put(dev);
				in6_dev_put(idev);
			}
1257
			dev = net->loopback_dev;
L
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1258 1259 1260 1261 1262 1263 1264
			dev_hold(dev);
			idev = in6_dev_get(dev);
			if (!idev) {
				err = -ENODEV;
				goto out;
			}
		}
1265 1266 1267
		rt->dst.output = ip6_pkt_discard_out;
		rt->dst.input = ip6_pkt_discard;
		rt->dst.error = -ENETUNREACH;
L
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1268 1269 1270 1271
		rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
		goto install_route;
	}

1272
	if (cfg->fc_flags & RTF_GATEWAY) {
L
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1273 1274 1275
		struct in6_addr *gw_addr;
		int gwa_type;

1276 1277
		gw_addr = &cfg->fc_gateway;
		ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
L
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1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293
		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;
			if (!(gwa_type&IPV6_ADDR_UNICAST))
				goto out;

1294
			grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
L
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1295 1296 1297 1298 1299 1300

			err = -EHOSTUNREACH;
			if (grt == NULL)
				goto out;
			if (dev) {
				if (dev != grt->rt6i_dev) {
1301
					dst_release(&grt->dst);
L
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1302 1303 1304 1305 1306 1307 1308 1309 1310 1311
					goto out;
				}
			} else {
				dev = grt->rt6i_dev;
				idev = grt->rt6i_idev;
				dev_hold(dev);
				in6_dev_hold(grt->rt6i_idev);
			}
			if (!(grt->rt6i_flags&RTF_GATEWAY))
				err = 0;
1312
			dst_release(&grt->dst);
L
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1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325

			if (err)
				goto out;
		}
		err = -EINVAL;
		if (dev == NULL || (dev->flags&IFF_LOOPBACK))
			goto out;
	}

	err = -ENODEV;
	if (dev == NULL)
		goto out;

1326
	if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
L
Linus Torvalds 已提交
1327 1328 1329 1330 1331 1332 1333 1334
		rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
		if (IS_ERR(rt->rt6i_nexthop)) {
			err = PTR_ERR(rt->rt6i_nexthop);
			rt->rt6i_nexthop = NULL;
			goto out;
		}
	}

1335
	rt->rt6i_flags = cfg->fc_flags;
L
Linus Torvalds 已提交
1336 1337

install_route:
1338 1339 1340 1341 1342
	if (cfg->fc_mx) {
		struct nlattr *nla;
		int remaining;

		nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1343
			int type = nla_type(nla);
1344 1345 1346

			if (type) {
				if (type > RTAX_MAX) {
L
Linus Torvalds 已提交
1347 1348 1349
					err = -EINVAL;
					goto out;
				}
1350

1351
				dst_metric_set(&rt->dst, type, nla_get_u32(nla));
L
Linus Torvalds 已提交
1352 1353 1354 1355
			}
		}
	}

1356
	rt->dst.dev = dev;
L
Linus Torvalds 已提交
1357
	rt->rt6i_idev = idev;
T
Thomas Graf 已提交
1358
	rt->rt6i_table = table;
1359

1360
	cfg->fc_nlinfo.nl_net = dev_net(dev);
1361

1362
	return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
L
Linus Torvalds 已提交
1363 1364 1365 1366 1367 1368 1369

out:
	if (dev)
		dev_put(dev);
	if (idev)
		in6_dev_put(idev);
	if (rt)
1370
		dst_free(&rt->dst);
L
Linus Torvalds 已提交
1371 1372 1373
	return err;
}

1374
static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
L
Linus Torvalds 已提交
1375 1376
{
	int err;
T
Thomas Graf 已提交
1377
	struct fib6_table *table;
1378
	struct net *net = dev_net(rt->rt6i_dev);
L
Linus Torvalds 已提交
1379

1380
	if (rt == net->ipv6.ip6_null_entry)
1381 1382
		return -ENOENT;

T
Thomas Graf 已提交
1383 1384
	table = rt->rt6i_table;
	write_lock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1385

1386
	err = fib6_del(rt, info);
1387
	dst_release(&rt->dst);
L
Linus Torvalds 已提交
1388

T
Thomas Graf 已提交
1389
	write_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1390 1391 1392 1393

	return err;
}

1394 1395
int ip6_del_rt(struct rt6_info *rt)
{
1396
	struct nl_info info = {
1397
		.nl_net = dev_net(rt->rt6i_dev),
1398
	};
1399
	return __ip6_del_rt(rt, &info);
1400 1401
}

1402
static int ip6_route_del(struct fib6_config *cfg)
L
Linus Torvalds 已提交
1403
{
T
Thomas Graf 已提交
1404
	struct fib6_table *table;
L
Linus Torvalds 已提交
1405 1406 1407 1408
	struct fib6_node *fn;
	struct rt6_info *rt;
	int err = -ESRCH;

1409
	table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
T
Thomas Graf 已提交
1410 1411 1412 1413
	if (table == NULL)
		return err;

	read_lock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1414

T
Thomas Graf 已提交
1415
	fn = fib6_locate(&table->tb6_root,
1416 1417
			 &cfg->fc_dst, cfg->fc_dst_len,
			 &cfg->fc_src, cfg->fc_src_len);
1418

L
Linus Torvalds 已提交
1419
	if (fn) {
1420
		for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1421
			if (cfg->fc_ifindex &&
L
Linus Torvalds 已提交
1422
			    (rt->rt6i_dev == NULL ||
1423
			     rt->rt6i_dev->ifindex != cfg->fc_ifindex))
L
Linus Torvalds 已提交
1424
				continue;
1425 1426
			if (cfg->fc_flags & RTF_GATEWAY &&
			    !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
L
Linus Torvalds 已提交
1427
				continue;
1428
			if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
L
Linus Torvalds 已提交
1429
				continue;
1430
			dst_hold(&rt->dst);
T
Thomas Graf 已提交
1431
			read_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1432

1433
			return __ip6_del_rt(rt, &cfg->fc_nlinfo);
L
Linus Torvalds 已提交
1434 1435
		}
	}
T
Thomas Graf 已提交
1436
	read_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1437 1438 1439 1440 1441 1442 1443

	return err;
}

/*
 *	Handle redirects
 */
1444 1445 1446 1447 1448
struct ip6rd_flowi {
	struct flowi fl;
	struct in6_addr gateway;
};

1449 1450
static struct rt6_info *__ip6_route_redirect(struct net *net,
					     struct fib6_table *table,
1451 1452
					     struct flowi *fl,
					     int flags)
L
Linus Torvalds 已提交
1453
{
1454 1455
	struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl;
	struct rt6_info *rt;
1456
	struct fib6_node *fn;
T
Thomas Graf 已提交
1457

L
Linus Torvalds 已提交
1458
	/*
1459 1460 1461 1462 1463 1464 1465 1466
	 * Get the "current" route for this destination and
	 * check if the redirect has come from approriate router.
	 *
	 * RFC 2461 specifies that redirects should only be
	 * accepted if they come from the nexthop to the target.
	 * Due to the way the routes are chosen, this notion
	 * is a bit fuzzy and one might need to check all possible
	 * routes.
L
Linus Torvalds 已提交
1467 1468
	 */

T
Thomas Graf 已提交
1469
	read_lock_bh(&table->tb6_lock);
1470
	fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
1471
restart:
1472
	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484
		/*
		 * Current route is on-link; redirect is always invalid.
		 *
		 * Seems, previous statement is not true. It could
		 * be node, which looks for us as on-link (f.e. proxy ndisc)
		 * But then router serving it might decide, that we should
		 * know truth 8)8) --ANK (980726).
		 */
		if (rt6_check_expired(rt))
			continue;
		if (!(rt->rt6i_flags & RTF_GATEWAY))
			continue;
1485
		if (fl->oif != rt->rt6i_dev->ifindex)
1486
			continue;
1487
		if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1488 1489 1490
			continue;
		break;
	}
1491

1492
	if (!rt)
1493 1494
		rt = net->ipv6.ip6_null_entry;
	BACKTRACK(net, &fl->fl6_src);
1495
out:
1496
	dst_hold(&rt->dst);
1497

T
Thomas Graf 已提交
1498
	read_unlock_bh(&table->tb6_lock);
1499

1500 1501 1502 1503 1504 1505 1506 1507
	return rt;
};

static struct rt6_info *ip6_route_redirect(struct in6_addr *dest,
					   struct in6_addr *src,
					   struct in6_addr *gateway,
					   struct net_device *dev)
{
1508
	int flags = RT6_LOOKUP_F_HAS_SADDR;
1509
	struct net *net = dev_net(dev);
1510 1511 1512
	struct ip6rd_flowi rdfl = {
		.fl = {
			.oif = dev->ifindex,
1513 1514
			.fl6_dst = *dest,
			.fl6_src = *src,
1515 1516
		},
	};
1517

1518 1519
	ipv6_addr_copy(&rdfl.gateway, gateway);

1520 1521
	if (rt6_need_strict(dest))
		flags |= RT6_LOOKUP_F_IFACE;
1522

1523
	return (struct rt6_info *)fib6_rule_lookup(net, (struct flowi *)&rdfl,
1524
						   flags, __ip6_route_redirect);
1525 1526 1527 1528 1529 1530 1531 1532
}

void rt6_redirect(struct in6_addr *dest, struct in6_addr *src,
		  struct in6_addr *saddr,
		  struct neighbour *neigh, u8 *lladdr, int on_link)
{
	struct rt6_info *rt, *nrt = NULL;
	struct netevent_redirect netevent;
1533
	struct net *net = dev_net(neigh->dev);
1534 1535 1536

	rt = ip6_route_redirect(dest, src, saddr, neigh->dev);

1537
	if (rt == net->ipv6.ip6_null_entry) {
L
Linus Torvalds 已提交
1538 1539 1540
		if (net_ratelimit())
			printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
			       "for redirect target\n");
1541
		goto out;
L
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1542 1543 1544 1545 1546 1547
	}

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

1548
	neigh_update(neigh, lladdr, NUD_STALE,
L
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1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559
		     NEIGH_UPDATE_F_WEAK_OVERRIDE|
		     NEIGH_UPDATE_F_OVERRIDE|
		     (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
				     NEIGH_UPDATE_F_ISROUTER))
		     );

	/*
	 * Redirect received -> path was valid.
	 * Look, redirects are sent only in response to data packets,
	 * so that this nexthop apparently is reachable. --ANK
	 */
1560
	dst_confirm(&rt->dst);
L
Linus Torvalds 已提交
1561 1562

	/* Duplicate redirect: silently ignore. */
1563
	if (neigh == rt->dst.neighbour)
L
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1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575
		goto out;

	nrt = ip6_rt_copy(rt);
	if (nrt == NULL)
		goto out;

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

	ipv6_addr_copy(&nrt->rt6i_dst.addr, dest);
	nrt->rt6i_dst.plen = 128;
1576
	nrt->dst.flags |= DST_HOST;
L
Linus Torvalds 已提交
1577 1578 1579 1580

	ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
	nrt->rt6i_nexthop = neigh_clone(neigh);

1581
	if (ip6_ins_rt(nrt))
L
Linus Torvalds 已提交
1582 1583
		goto out;

1584 1585
	netevent.old = &rt->dst;
	netevent.new = &nrt->dst;
1586 1587
	call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);

L
Linus Torvalds 已提交
1588
	if (rt->rt6i_flags&RTF_CACHE) {
1589
		ip6_del_rt(rt);
L
Linus Torvalds 已提交
1590 1591 1592 1593
		return;
	}

out:
1594
	dst_release(&rt->dst);
L
Linus Torvalds 已提交
1595 1596 1597 1598 1599 1600 1601
}

/*
 *	Handle ICMP "packet too big" messages
 *	i.e. Path MTU discovery
 */

1602 1603
static void rt6_do_pmtu_disc(struct in6_addr *daddr, struct in6_addr *saddr,
			     struct net *net, u32 pmtu, int ifindex)
L
Linus Torvalds 已提交
1604 1605 1606
{
	struct rt6_info *rt, *nrt;
	int allfrag = 0;
1607
again:
1608
	rt = rt6_lookup(net, daddr, saddr, ifindex, 0);
L
Linus Torvalds 已提交
1609 1610 1611
	if (rt == NULL)
		return;

1612 1613 1614 1615 1616
	if (rt6_check_expired(rt)) {
		ip6_del_rt(rt);
		goto again;
	}

1617
	if (pmtu >= dst_mtu(&rt->dst))
L
Linus Torvalds 已提交
1618 1619 1620 1621
		goto out;

	if (pmtu < IPV6_MIN_MTU) {
		/*
1622
		 * According to RFC2460, PMTU is set to the IPv6 Minimum Link
L
Linus Torvalds 已提交
1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634
		 * MTU (1280) and a fragment header should always be included
		 * after a node receiving Too Big message reporting PMTU is
		 * less than the IPv6 Minimum Link MTU.
		 */
		pmtu = IPV6_MIN_MTU;
		allfrag = 1;
	}

	/* New mtu received -> path was valid.
	   They are sent only in response to data packets,
	   so that this nexthop apparently is reachable. --ANK
	 */
1635
	dst_confirm(&rt->dst);
L
Linus Torvalds 已提交
1636 1637 1638 1639 1640 1641 1642

	/* Host route. If it is static, it would be better
	   not to override it, but add new one, so that
	   when cache entry will expire old pmtu
	   would return automatically.
	 */
	if (rt->rt6i_flags & RTF_CACHE) {
1643 1644 1645 1646 1647 1648
		dst_metric_set(&rt->dst, RTAX_MTU, pmtu);
		if (allfrag) {
			u32 features = dst_metric(&rt->dst, RTAX_FEATURES);
			features |= RTAX_FEATURE_ALLFRAG;
			dst_metric_set(&rt->dst, RTAX_FEATURES, features);
		}
1649
		dst_set_expires(&rt->dst, net->ipv6.sysctl.ip6_rt_mtu_expires);
L
Linus Torvalds 已提交
1650 1651 1652 1653 1654 1655 1656 1657 1658
		rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES;
		goto out;
	}

	/* Network route.
	   Two cases are possible:
	   1. It is connected route. Action: COW
	   2. It is gatewayed route or NONEXTHOP route. Action: clone it.
	 */
1659
	if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
1660
		nrt = rt6_alloc_cow(rt, daddr, saddr);
1661 1662
	else
		nrt = rt6_alloc_clone(rt, daddr);
1663

1664
	if (nrt) {
1665 1666 1667 1668 1669 1670
		dst_metric_set(&nrt->dst, RTAX_MTU, pmtu);
		if (allfrag) {
			u32 features = dst_metric(&nrt->dst, RTAX_FEATURES);
			features |= RTAX_FEATURE_ALLFRAG;
			dst_metric_set(&nrt->dst, RTAX_FEATURES, features);
		}
1671 1672 1673 1674 1675 1676 1677

		/* According to RFC 1981, detecting PMTU increase shouldn't be
		 * happened within 5 mins, the recommended timer is 10 mins.
		 * Here this route expiration time is set to ip6_rt_mtu_expires
		 * which is 10 mins. After 10 mins the decreased pmtu is expired
		 * and detecting PMTU increase will be automatically happened.
		 */
1678
		dst_set_expires(&nrt->dst, net->ipv6.sysctl.ip6_rt_mtu_expires);
1679 1680
		nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;

1681
		ip6_ins_rt(nrt);
L
Linus Torvalds 已提交
1682 1683
	}
out:
1684
	dst_release(&rt->dst);
L
Linus Torvalds 已提交
1685 1686
}

1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707
void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr,
			struct net_device *dev, u32 pmtu)
{
	struct net *net = dev_net(dev);

	/*
	 * RFC 1981 states that a node "MUST reduce the size of the packets it
	 * is sending along the path" that caused the Packet Too Big message.
	 * Since it's not possible in the general case to determine which
	 * interface was used to send the original packet, we update the MTU
	 * on the interface that will be used to send future packets. We also
	 * update the MTU on the interface that received the Packet Too Big in
	 * case the original packet was forced out that interface with
	 * SO_BINDTODEVICE or similar. This is the next best thing to the
	 * correct behaviour, which would be to update the MTU on all
	 * interfaces.
	 */
	rt6_do_pmtu_disc(daddr, saddr, net, pmtu, 0);
	rt6_do_pmtu_disc(daddr, saddr, net, pmtu, dev->ifindex);
}

L
Linus Torvalds 已提交
1708 1709 1710 1711 1712 1713
/*
 *	Misc support functions
 */

static struct rt6_info * ip6_rt_copy(struct rt6_info *ort)
{
1714
	struct net *net = dev_net(ort->rt6i_dev);
1715
	struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
L
Linus Torvalds 已提交
1716 1717

	if (rt) {
1718 1719 1720
		rt->dst.input = ort->dst.input;
		rt->dst.output = ort->dst.output;

1721
		dst_copy_metrics(&rt->dst, &ort->dst);
1722 1723 1724 1725
		rt->dst.error = ort->dst.error;
		rt->dst.dev = ort->dst.dev;
		if (rt->dst.dev)
			dev_hold(rt->dst.dev);
L
Linus Torvalds 已提交
1726 1727 1728
		rt->rt6i_idev = ort->rt6i_idev;
		if (rt->rt6i_idev)
			in6_dev_hold(rt->rt6i_idev);
1729
		rt->dst.lastuse = jiffies;
L
Linus Torvalds 已提交
1730 1731 1732 1733 1734 1735 1736 1737 1738 1739
		rt->rt6i_expires = 0;

		ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
		rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
		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
T
Thomas Graf 已提交
1740
		rt->rt6i_table = ort->rt6i_table;
L
Linus Torvalds 已提交
1741 1742 1743 1744
	}
	return rt;
}

1745
#ifdef CONFIG_IPV6_ROUTE_INFO
1746 1747
static struct rt6_info *rt6_get_route_info(struct net *net,
					   struct in6_addr *prefix, int prefixlen,
1748 1749 1750 1751
					   struct in6_addr *gwaddr, int ifindex)
{
	struct fib6_node *fn;
	struct rt6_info *rt = NULL;
T
Thomas Graf 已提交
1752 1753
	struct fib6_table *table;

1754
	table = fib6_get_table(net, RT6_TABLE_INFO);
T
Thomas Graf 已提交
1755 1756
	if (table == NULL)
		return NULL;
1757

T
Thomas Graf 已提交
1758 1759
	write_lock_bh(&table->tb6_lock);
	fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1760 1761 1762
	if (!fn)
		goto out;

1763
	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1764 1765 1766 1767 1768 1769
		if (rt->rt6i_dev->ifindex != ifindex)
			continue;
		if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
			continue;
		if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
			continue;
1770
		dst_hold(&rt->dst);
1771 1772 1773
		break;
	}
out:
T
Thomas Graf 已提交
1774
	write_unlock_bh(&table->tb6_lock);
1775 1776 1777
	return rt;
}

1778 1779
static struct rt6_info *rt6_add_route_info(struct net *net,
					   struct in6_addr *prefix, int prefixlen,
1780 1781 1782
					   struct in6_addr *gwaddr, int ifindex,
					   unsigned pref)
{
1783 1784
	struct fib6_config cfg = {
		.fc_table	= RT6_TABLE_INFO,
1785
		.fc_metric	= IP6_RT_PRIO_USER,
1786 1787 1788 1789
		.fc_ifindex	= ifindex,
		.fc_dst_len	= prefixlen,
		.fc_flags	= RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
				  RTF_UP | RTF_PREF(pref),
1790 1791 1792
		.fc_nlinfo.pid = 0,
		.fc_nlinfo.nlh = NULL,
		.fc_nlinfo.nl_net = net,
1793 1794 1795 1796
	};

	ipv6_addr_copy(&cfg.fc_dst, prefix);
	ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1797

1798 1799
	/* We should treat it as a default route if prefix length is 0. */
	if (!prefixlen)
1800
		cfg.fc_flags |= RTF_DEFAULT;
1801

1802
	ip6_route_add(&cfg);
1803

1804
	return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
1805 1806 1807
}
#endif

L
Linus Torvalds 已提交
1808
struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev)
1809
{
L
Linus Torvalds 已提交
1810
	struct rt6_info *rt;
T
Thomas Graf 已提交
1811
	struct fib6_table *table;
L
Linus Torvalds 已提交
1812

1813
	table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
T
Thomas Graf 已提交
1814 1815
	if (table == NULL)
		return NULL;
L
Linus Torvalds 已提交
1816

T
Thomas Graf 已提交
1817
	write_lock_bh(&table->tb6_lock);
1818
	for (rt = table->tb6_root.leaf; rt; rt=rt->dst.rt6_next) {
L
Linus Torvalds 已提交
1819
		if (dev == rt->rt6i_dev &&
1820
		    ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
L
Linus Torvalds 已提交
1821 1822 1823 1824
		    ipv6_addr_equal(&rt->rt6i_gateway, addr))
			break;
	}
	if (rt)
1825
		dst_hold(&rt->dst);
T
Thomas Graf 已提交
1826
	write_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1827 1828 1829 1830
	return rt;
}

struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr,
1831 1832
				     struct net_device *dev,
				     unsigned int pref)
L
Linus Torvalds 已提交
1833
{
1834 1835
	struct fib6_config cfg = {
		.fc_table	= RT6_TABLE_DFLT,
1836
		.fc_metric	= IP6_RT_PRIO_USER,
1837 1838 1839
		.fc_ifindex	= dev->ifindex,
		.fc_flags	= RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
				  RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1840 1841
		.fc_nlinfo.pid = 0,
		.fc_nlinfo.nlh = NULL,
1842
		.fc_nlinfo.nl_net = dev_net(dev),
1843
	};
L
Linus Torvalds 已提交
1844

1845
	ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
L
Linus Torvalds 已提交
1846

1847
	ip6_route_add(&cfg);
L
Linus Torvalds 已提交
1848 1849 1850 1851

	return rt6_get_dflt_router(gwaddr, dev);
}

1852
void rt6_purge_dflt_routers(struct net *net)
L
Linus Torvalds 已提交
1853 1854
{
	struct rt6_info *rt;
T
Thomas Graf 已提交
1855 1856 1857
	struct fib6_table *table;

	/* NOTE: Keep consistent with rt6_get_dflt_router */
1858
	table = fib6_get_table(net, RT6_TABLE_DFLT);
T
Thomas Graf 已提交
1859 1860
	if (table == NULL)
		return;
L
Linus Torvalds 已提交
1861 1862

restart:
T
Thomas Graf 已提交
1863
	read_lock_bh(&table->tb6_lock);
1864
	for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
L
Linus Torvalds 已提交
1865
		if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1866
			dst_hold(&rt->dst);
T
Thomas Graf 已提交
1867
			read_unlock_bh(&table->tb6_lock);
1868
			ip6_del_rt(rt);
L
Linus Torvalds 已提交
1869 1870 1871
			goto restart;
		}
	}
T
Thomas Graf 已提交
1872
	read_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
1873 1874
}

1875 1876
static void rtmsg_to_fib6_config(struct net *net,
				 struct in6_rtmsg *rtmsg,
1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888
				 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;

1889
	cfg->fc_nlinfo.nl_net = net;
1890

1891 1892 1893 1894 1895
	ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst);
	ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src);
	ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway);
}

1896
int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
L
Linus Torvalds 已提交
1897
{
1898
	struct fib6_config cfg;
L
Linus Torvalds 已提交
1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910
	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;
1911

1912
		rtmsg_to_fib6_config(net, &rtmsg, &cfg);
1913

L
Linus Torvalds 已提交
1914 1915 1916
		rtnl_lock();
		switch (cmd) {
		case SIOCADDRT:
1917
			err = ip6_route_add(&cfg);
L
Linus Torvalds 已提交
1918 1919
			break;
		case SIOCDELRT:
1920
			err = ip6_route_del(&cfg);
L
Linus Torvalds 已提交
1921 1922 1923 1924 1925 1926 1927
			break;
		default:
			err = -EINVAL;
		}
		rtnl_unlock();

		return err;
1928
	}
L
Linus Torvalds 已提交
1929 1930 1931 1932 1933 1934 1935 1936

	return -EINVAL;
}

/*
 *	Drop the packet on the floor
 */

1937
static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
L
Linus Torvalds 已提交
1938
{
1939
	int type;
E
Eric Dumazet 已提交
1940
	struct dst_entry *dst = skb_dst(skb);
1941 1942
	switch (ipstats_mib_noroutes) {
	case IPSTATS_MIB_INNOROUTES:
1943
		type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
U
Ulrich Weber 已提交
1944
		if (type == IPV6_ADDR_ANY) {
1945 1946
			IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
				      IPSTATS_MIB_INADDRERRORS);
1947 1948 1949 1950
			break;
		}
		/* FALLTHROUGH */
	case IPSTATS_MIB_OUTNOROUTES:
1951 1952
		IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
			      ipstats_mib_noroutes);
1953 1954
		break;
	}
1955
	icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
L
Linus Torvalds 已提交
1956 1957 1958 1959
	kfree_skb(skb);
	return 0;
}

1960 1961
static int ip6_pkt_discard(struct sk_buff *skb)
{
1962
	return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
1963 1964
}

1965
static int ip6_pkt_discard_out(struct sk_buff *skb)
L
Linus Torvalds 已提交
1966
{
E
Eric Dumazet 已提交
1967
	skb->dev = skb_dst(skb)->dev;
1968
	return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
L
Linus Torvalds 已提交
1969 1970
}

1971 1972
#ifdef CONFIG_IPV6_MULTIPLE_TABLES

1973 1974
static int ip6_pkt_prohibit(struct sk_buff *skb)
{
1975
	return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
1976 1977 1978 1979
}

static int ip6_pkt_prohibit_out(struct sk_buff *skb)
{
E
Eric Dumazet 已提交
1980
	skb->dev = skb_dst(skb)->dev;
1981
	return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
1982 1983
}

1984 1985
#endif

L
Linus Torvalds 已提交
1986 1987 1988 1989 1990 1991 1992 1993
/*
 *	Allocate a dst for local (unicast / anycast) address.
 */

struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
				    const struct in6_addr *addr,
				    int anycast)
{
1994
	struct net *net = dev_net(idev->dev);
1995
	struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops);
1996
	struct neighbour *neigh;
L
Linus Torvalds 已提交
1997

1998 1999 2000 2001
	if (rt == NULL) {
		if (net_ratelimit())
			pr_warning("IPv6:  Maximum number of routes reached,"
				   " consider increasing route/max_size.\n");
L
Linus Torvalds 已提交
2002
		return ERR_PTR(-ENOMEM);
2003
	}
L
Linus Torvalds 已提交
2004

2005
	dev_hold(net->loopback_dev);
L
Linus Torvalds 已提交
2006 2007
	in6_dev_hold(idev);

2008 2009 2010
	rt->dst.flags = DST_HOST;
	rt->dst.input = ip6_input;
	rt->dst.output = ip6_output;
2011
	rt->rt6i_dev = net->loopback_dev;
L
Linus Torvalds 已提交
2012
	rt->rt6i_idev = idev;
2013
	dst_metric_set(&rt->dst, RTAX_HOPLIMIT, -1);
2014
	rt->dst.obsolete = -1;
L
Linus Torvalds 已提交
2015 2016

	rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2017 2018 2019
	if (anycast)
		rt->rt6i_flags |= RTF_ANYCAST;
	else
L
Linus Torvalds 已提交
2020
		rt->rt6i_flags |= RTF_LOCAL;
2021 2022
	neigh = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
	if (IS_ERR(neigh)) {
2023
		dst_free(&rt->dst);
2024 2025 2026 2027 2028 2029 2030

		/* We are casting this because that is the return
		 * value type.  But an errno encoded pointer is the
		 * same regardless of the underlying pointer type,
		 * and that's what we are returning.  So this is OK.
		 */
		return (struct rt6_info *) neigh;
L
Linus Torvalds 已提交
2031
	}
2032
	rt->rt6i_nexthop = neigh;
L
Linus Torvalds 已提交
2033 2034 2035

	ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
	rt->rt6i_dst.plen = 128;
2036
	rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
L
Linus Torvalds 已提交
2037

2038
	atomic_set(&rt->dst.__refcnt, 1);
L
Linus Torvalds 已提交
2039 2040 2041 2042

	return rt;
}

2043 2044 2045 2046 2047
struct arg_dev_net {
	struct net_device *dev;
	struct net *net;
};

L
Linus Torvalds 已提交
2048 2049
static int fib6_ifdown(struct rt6_info *rt, void *arg)
{
S
stephen hemminger 已提交
2050 2051
	const struct arg_dev_net *adn = arg;
	const struct net_device *dev = adn->dev;
2052

S
stephen hemminger 已提交
2053 2054
	if ((rt->rt6i_dev == dev || dev == NULL) &&
	    rt != adn->net->ipv6.ip6_null_entry) {
L
Linus Torvalds 已提交
2055 2056 2057 2058 2059 2060
		RT6_TRACE("deleted by ifdown %p\n", rt);
		return -1;
	}
	return 0;
}

2061
void rt6_ifdown(struct net *net, struct net_device *dev)
L
Linus Torvalds 已提交
2062
{
2063 2064 2065 2066 2067 2068
	struct arg_dev_net adn = {
		.dev = dev,
		.net = net,
	};

	fib6_clean_all(net, fib6_ifdown, 0, &adn);
2069
	icmp6_clean_all(fib6_ifdown, &adn);
L
Linus Torvalds 已提交
2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107
}

struct rt6_mtu_change_arg
{
	struct net_device *dev;
	unsigned mtu;
};

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);
	if (idev == NULL)
		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.
	 */
	if (rt->rt6i_dev == arg->dev &&
2108 2109 2110 2111
	    !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))) {
2112
		dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2113
	}
L
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2114 2115 2116 2117 2118
	return 0;
}

void rt6_mtu_change(struct net_device *dev, unsigned mtu)
{
T
Thomas Graf 已提交
2119 2120 2121 2122
	struct rt6_mtu_change_arg arg = {
		.dev = dev,
		.mtu = mtu,
	};
L
Linus Torvalds 已提交
2123

2124
	fib6_clean_all(dev_net(dev), rt6_mtu_change_route, 0, &arg);
L
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2125 2126
}

2127
static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2128
	[RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2129
	[RTA_OIF]               = { .type = NLA_U32 },
2130
	[RTA_IIF]		= { .type = NLA_U32 },
2131 2132 2133 2134 2135 2136
	[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
2137
{
2138 2139 2140
	struct rtmsg *rtm;
	struct nlattr *tb[RTA_MAX+1];
	int err;
L
Linus Torvalds 已提交
2141

2142 2143 2144
	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
	if (err < 0)
		goto errout;
L
Linus Torvalds 已提交
2145

2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158
	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;

2159 2160 2161
	if (rtm->rtm_type == RTN_LOCAL)
		cfg->fc_flags |= RTF_LOCAL;

2162 2163
	cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
	cfg->fc_nlinfo.nlh = nlh;
2164
	cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2165 2166 2167 2168

	if (tb[RTA_GATEWAY]) {
		nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
		cfg->fc_flags |= RTF_GATEWAY;
L
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2169
	}
2170 2171 2172 2173 2174 2175 2176 2177

	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
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2178
	}
2179 2180 2181 2182 2183 2184 2185 2186

	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
2187
	}
2188 2189 2190 2191 2192 2193 2194 2195 2196 2197

	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
2198
	}
2199 2200 2201 2202 2203 2204 2205

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

	err = 0;
errout:
	return err;
L
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2206 2207
}

2208
static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
L
Linus Torvalds 已提交
2209
{
2210 2211
	struct fib6_config cfg;
	int err;
L
Linus Torvalds 已提交
2212

2213 2214 2215 2216 2217
	err = rtm_to_fib6_config(skb, nlh, &cfg);
	if (err < 0)
		return err;

	return ip6_route_del(&cfg);
L
Linus Torvalds 已提交
2218 2219
}

2220
static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
L
Linus Torvalds 已提交
2221
{
2222 2223
	struct fib6_config cfg;
	int err;
L
Linus Torvalds 已提交
2224

2225 2226 2227 2228 2229
	err = rtm_to_fib6_config(skb, nlh, &cfg);
	if (err < 0)
		return err;

	return ip6_route_add(&cfg);
L
Linus Torvalds 已提交
2230 2231
}

2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242
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 */
2243
	       + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2244 2245 2246
	       + nla_total_size(sizeof(struct rta_cacheinfo));
}

2247 2248
static int rt6_fill_node(struct net *net,
			 struct sk_buff *skb, struct rt6_info *rt,
2249 2250
			 struct in6_addr *dst, struct in6_addr *src,
			 int iif, int type, u32 pid, u32 seq,
2251
			 int prefix, int nowait, unsigned int flags)
L
Linus Torvalds 已提交
2252 2253
{
	struct rtmsg *rtm;
2254
	struct nlmsghdr *nlh;
2255
	long expires;
2256
	u32 table;
L
Linus Torvalds 已提交
2257 2258 2259 2260 2261 2262 2263 2264

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

2265 2266
	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
	if (nlh == NULL)
2267
		return -EMSGSIZE;
2268 2269

	rtm = nlmsg_data(nlh);
L
Linus Torvalds 已提交
2270 2271 2272 2273
	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
2274
	if (rt->rt6i_table)
2275
		table = rt->rt6i_table->tb6_id;
T
Thomas Graf 已提交
2276
	else
2277 2278
		table = RT6_TABLE_UNSPEC;
	rtm->rtm_table = table;
2279
	NLA_PUT_U32(skb, RTA_TABLE, table);
L
Linus Torvalds 已提交
2280 2281
	if (rt->rt6i_flags&RTF_REJECT)
		rtm->rtm_type = RTN_UNREACHABLE;
2282 2283
	else if (rt->rt6i_flags&RTF_LOCAL)
		rtm->rtm_type = RTN_LOCAL;
L
Linus Torvalds 已提交
2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301
	else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK))
		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;
	if (rt->rt6i_flags&RTF_DYNAMIC)
		rtm->rtm_protocol = RTPROT_REDIRECT;
	else if (rt->rt6i_flags & RTF_ADDRCONF)
		rtm->rtm_protocol = RTPROT_KERNEL;
	else if (rt->rt6i_flags&RTF_DEFAULT)
		rtm->rtm_protocol = RTPROT_RA;

	if (rt->rt6i_flags&RTF_CACHE)
		rtm->rtm_flags |= RTM_F_CLONED;

	if (dst) {
2302
		NLA_PUT(skb, RTA_DST, 16, dst);
2303
		rtm->rtm_dst_len = 128;
L
Linus Torvalds 已提交
2304
	} else if (rtm->rtm_dst_len)
2305
		NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
L
Linus Torvalds 已提交
2306 2307
#ifdef CONFIG_IPV6_SUBTREES
	if (src) {
2308
		NLA_PUT(skb, RTA_SRC, 16, src);
2309
		rtm->rtm_src_len = 128;
L
Linus Torvalds 已提交
2310
	} else if (rtm->rtm_src_len)
2311
		NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
L
Linus Torvalds 已提交
2312
#endif
2313 2314 2315
	if (iif) {
#ifdef CONFIG_IPV6_MROUTE
		if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
2316
			int err = ip6mr_get_route(net, skb, rtm, nowait);
2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330
			if (err <= 0) {
				if (!nowait) {
					if (err == 0)
						return 0;
					goto nla_put_failure;
				} else {
					if (err == -EMSGSIZE)
						goto nla_put_failure;
				}
			}
		} else
#endif
			NLA_PUT_U32(skb, RTA_IIF, iif);
	} else if (dst) {
2331
		struct inet6_dev *idev = ip6_dst_idev(&rt->dst);
L
Linus Torvalds 已提交
2332
		struct in6_addr saddr_buf;
2333
		if (ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2334
				       dst, 0, &saddr_buf) == 0)
2335
			NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
L
Linus Torvalds 已提交
2336
	}
2337

2338
	if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
2339 2340
		goto nla_put_failure;

2341 2342
	if (rt->dst.neighbour)
		NLA_PUT(skb, RTA_GATEWAY, 16, &rt->dst.neighbour->primary_key);
2343

2344
	if (rt->dst.dev)
2345 2346 2347
		NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);

	NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2348

2349 2350 2351 2352 2353 2354
	if (!(rt->rt6i_flags & RTF_EXPIRES))
		expires = 0;
	else if (rt->rt6i_expires - jiffies < INT_MAX)
		expires = rt->rt6i_expires - jiffies;
	else
		expires = INT_MAX;
2355

2356 2357
	if (rtnl_put_cacheinfo(skb, &rt->dst, 0, 0, 0,
			       expires, rt->dst.error) < 0)
2358
		goto nla_put_failure;
2359 2360 2361 2362

	return nlmsg_end(skb, nlh);

nla_put_failure:
2363 2364
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
L
Linus Torvalds 已提交
2365 2366
}

2367
int rt6_dump_route(struct rt6_info *rt, void *p_arg)
L
Linus Torvalds 已提交
2368 2369 2370 2371
{
	struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
	int prefix;

2372 2373
	if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
		struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
L
Linus Torvalds 已提交
2374 2375 2376 2377
		prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
	} else
		prefix = 0;

2378 2379
	return rt6_fill_node(arg->net,
		     arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
L
Linus Torvalds 已提交
2380
		     NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2381
		     prefix, 0, NLM_F_MULTI);
L
Linus Torvalds 已提交
2382 2383
}

2384
static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
L
Linus Torvalds 已提交
2385
{
2386
	struct net *net = sock_net(in_skb->sk);
2387 2388
	struct nlattr *tb[RTA_MAX+1];
	struct rt6_info *rt;
L
Linus Torvalds 已提交
2389
	struct sk_buff *skb;
2390
	struct rtmsg *rtm;
L
Linus Torvalds 已提交
2391
	struct flowi fl;
2392
	int err, iif = 0;
L
Linus Torvalds 已提交
2393

2394 2395 2396
	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
	if (err < 0)
		goto errout;
L
Linus Torvalds 已提交
2397

2398
	err = -EINVAL;
L
Linus Torvalds 已提交
2399 2400
	memset(&fl, 0, sizeof(fl));

2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419
	if (tb[RTA_SRC]) {
		if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
			goto errout;

		ipv6_addr_copy(&fl.fl6_src, nla_data(tb[RTA_SRC]));
	}

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

		ipv6_addr_copy(&fl.fl6_dst, nla_data(tb[RTA_DST]));
	}

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

	if (tb[RTA_OIF])
		fl.oif = nla_get_u32(tb[RTA_OIF]);
L
Linus Torvalds 已提交
2420 2421 2422

	if (iif) {
		struct net_device *dev;
2423
		dev = __dev_get_by_index(net, iif);
L
Linus Torvalds 已提交
2424 2425
		if (!dev) {
			err = -ENODEV;
2426
			goto errout;
L
Linus Torvalds 已提交
2427 2428 2429
		}
	}

2430 2431 2432 2433 2434
	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
	if (skb == NULL) {
		err = -ENOBUFS;
		goto errout;
	}
L
Linus Torvalds 已提交
2435

2436 2437 2438
	/* Reserve room for dummy headers, this skb can pass
	   through good chunk of routing engine.
	 */
2439
	skb_reset_mac_header(skb);
2440
	skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
L
Linus Torvalds 已提交
2441

2442
	rt = (struct rt6_info*) ip6_route_output(net, NULL, &fl);
2443
	skb_dst_set(skb, &rt->dst);
L
Linus Torvalds 已提交
2444

2445
	err = rt6_fill_node(net, skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
L
Linus Torvalds 已提交
2446
			    RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2447
			    nlh->nlmsg_seq, 0, 0, 0);
L
Linus Torvalds 已提交
2448
	if (err < 0) {
2449 2450
		kfree_skb(skb);
		goto errout;
L
Linus Torvalds 已提交
2451 2452
	}

2453
	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2454
errout:
L
Linus Torvalds 已提交
2455 2456 2457
	return err;
}

2458
void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
L
Linus Torvalds 已提交
2459 2460
{
	struct sk_buff *skb;
2461
	struct net *net = info->nl_net;
2462 2463 2464 2465 2466
	u32 seq;
	int err;

	err = -ENOBUFS;
	seq = info->nlh != NULL ? info->nlh->nlmsg_seq : 0;
2467

2468
	skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2469 2470 2471
	if (skb == NULL)
		goto errout;

2472
	err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
2473
				event, info->pid, seq, 0, 0, 0);
2474 2475 2476 2477 2478 2479
	if (err < 0) {
		/* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(skb);
		goto errout;
	}
2480 2481 2482
	rtnl_notify(skb, net, info->pid, RTNLGRP_IPV6_ROUTE,
		    info->nlh, gfp_any());
	return;
2483 2484
errout:
	if (err < 0)
2485
		rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
L
Linus Torvalds 已提交
2486 2487
}

2488 2489 2490 2491
static int ip6_route_dev_notify(struct notifier_block *this,
				unsigned long event, void *data)
{
	struct net_device *dev = (struct net_device *)data;
2492
	struct net *net = dev_net(dev);
2493 2494

	if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
2495
		net->ipv6.ip6_null_entry->dst.dev = dev;
2496 2497
		net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
2498
		net->ipv6.ip6_prohibit_entry->dst.dev = dev;
2499
		net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
2500
		net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
2501 2502 2503 2504 2505 2506 2507
		net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
#endif
	}

	return NOTIFY_OK;
}

L
Linus Torvalds 已提交
2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524
/*
 *	/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)
{
2525
	struct seq_file *m = p_arg;
L
Linus Torvalds 已提交
2526

2527
	seq_printf(m, "%pi6 %02x ", &rt->rt6i_dst.addr, rt->rt6i_dst.plen);
L
Linus Torvalds 已提交
2528 2529

#ifdef CONFIG_IPV6_SUBTREES
2530
	seq_printf(m, "%pi6 %02x ", &rt->rt6i_src.addr, rt->rt6i_src.plen);
L
Linus Torvalds 已提交
2531
#else
2532
	seq_puts(m, "00000000000000000000000000000000 00 ");
L
Linus Torvalds 已提交
2533 2534 2535
#endif

	if (rt->rt6i_nexthop) {
2536
		seq_printf(m, "%pi6", rt->rt6i_nexthop->primary_key);
L
Linus Torvalds 已提交
2537
	} else {
2538
		seq_puts(m, "00000000000000000000000000000000");
L
Linus Torvalds 已提交
2539
	}
2540
	seq_printf(m, " %08x %08x %08x %08x %8s\n",
2541 2542
		   rt->rt6i_metric, atomic_read(&rt->dst.__refcnt),
		   rt->dst.__use, rt->rt6i_flags,
2543
		   rt->rt6i_dev ? rt->rt6i_dev->name : "");
L
Linus Torvalds 已提交
2544 2545 2546
	return 0;
}

2547
static int ipv6_route_show(struct seq_file *m, void *v)
L
Linus Torvalds 已提交
2548
{
2549 2550
	struct net *net = (struct net *)m->private;
	fib6_clean_all(net, rt6_info_route, 0, m);
2551 2552
	return 0;
}
L
Linus Torvalds 已提交
2553

2554 2555
static int ipv6_route_open(struct inode *inode, struct file *file)
{
2556
	return single_open_net(inode, file, ipv6_route_show);
2557 2558
}

2559 2560 2561 2562 2563
static const struct file_operations ipv6_route_proc_fops = {
	.owner		= THIS_MODULE,
	.open		= ipv6_route_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
2564
	.release	= single_release_net,
2565 2566
};

L
Linus Torvalds 已提交
2567 2568
static int rt6_stats_seq_show(struct seq_file *seq, void *v)
{
2569
	struct net *net = (struct net *)seq->private;
L
Linus Torvalds 已提交
2570
	seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2571 2572 2573 2574 2575
		   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,
2576
		   dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
2577
		   net->ipv6.rt6_stats->fib_discarded_routes);
L
Linus Torvalds 已提交
2578 2579 2580 2581 2582 2583

	return 0;
}

static int rt6_stats_seq_open(struct inode *inode, struct file *file)
{
2584
	return single_open_net(inode, file, rt6_stats_seq_show);
2585 2586
}

2587
static const struct file_operations rt6_stats_seq_fops = {
L
Linus Torvalds 已提交
2588 2589 2590 2591
	.owner	 = THIS_MODULE,
	.open	 = rt6_stats_seq_open,
	.read	 = seq_read,
	.llseek	 = seq_lseek,
2592
	.release = single_release_net,
L
Linus Torvalds 已提交
2593 2594 2595 2596 2597 2598
};
#endif	/* CONFIG_PROC_FS */

#ifdef CONFIG_SYSCTL

static
2599
int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write,
L
Linus Torvalds 已提交
2600 2601
			      void __user *buffer, size_t *lenp, loff_t *ppos)
{
2602 2603
	struct net *net = current->nsproxy->net_ns;
	int delay = net->ipv6.sysctl.flush_delay;
L
Linus Torvalds 已提交
2604
	if (write) {
2605
		proc_dointvec(ctl, write, buffer, lenp, ppos);
2606
		fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay, net);
L
Linus Torvalds 已提交
2607 2608 2609 2610 2611
		return 0;
	} else
		return -EINVAL;
}

2612
ctl_table ipv6_route_table_template[] = {
2613
	{
L
Linus Torvalds 已提交
2614
		.procname	=	"flush",
2615
		.data		=	&init_net.ipv6.sysctl.flush_delay,
L
Linus Torvalds 已提交
2616
		.maxlen		=	sizeof(int),
2617
		.mode		=	0200,
A
Alexey Dobriyan 已提交
2618
		.proc_handler	=	ipv6_sysctl_rtcache_flush
L
Linus Torvalds 已提交
2619 2620 2621
	},
	{
		.procname	=	"gc_thresh",
2622
		.data		=	&ip6_dst_ops_template.gc_thresh,
L
Linus Torvalds 已提交
2623 2624
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2625
		.proc_handler	=	proc_dointvec,
L
Linus Torvalds 已提交
2626 2627 2628
	},
	{
		.procname	=	"max_size",
2629
		.data		=	&init_net.ipv6.sysctl.ip6_rt_max_size,
L
Linus Torvalds 已提交
2630 2631
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2632
		.proc_handler	=	proc_dointvec,
L
Linus Torvalds 已提交
2633 2634 2635
	},
	{
		.procname	=	"gc_min_interval",
2636
		.data		=	&init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
L
Linus Torvalds 已提交
2637 2638
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2639
		.proc_handler	=	proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2640 2641 2642
	},
	{
		.procname	=	"gc_timeout",
2643
		.data		=	&init_net.ipv6.sysctl.ip6_rt_gc_timeout,
L
Linus Torvalds 已提交
2644 2645
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2646
		.proc_handler	=	proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2647 2648 2649
	},
	{
		.procname	=	"gc_interval",
2650
		.data		=	&init_net.ipv6.sysctl.ip6_rt_gc_interval,
L
Linus Torvalds 已提交
2651 2652
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2653
		.proc_handler	=	proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2654 2655 2656
	},
	{
		.procname	=	"gc_elasticity",
2657
		.data		=	&init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
L
Linus Torvalds 已提交
2658 2659
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2660
		.proc_handler	=	proc_dointvec,
L
Linus Torvalds 已提交
2661 2662 2663
	},
	{
		.procname	=	"mtu_expires",
2664
		.data		=	&init_net.ipv6.sysctl.ip6_rt_mtu_expires,
L
Linus Torvalds 已提交
2665 2666
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2667
		.proc_handler	=	proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2668 2669 2670
	},
	{
		.procname	=	"min_adv_mss",
2671
		.data		=	&init_net.ipv6.sysctl.ip6_rt_min_advmss,
L
Linus Torvalds 已提交
2672 2673
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2674
		.proc_handler	=	proc_dointvec,
L
Linus Torvalds 已提交
2675 2676 2677
	},
	{
		.procname	=	"gc_min_interval_ms",
2678
		.data		=	&init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
L
Linus Torvalds 已提交
2679 2680
		.maxlen		=	sizeof(int),
		.mode		=	0644,
A
Alexey Dobriyan 已提交
2681
		.proc_handler	=	proc_dointvec_ms_jiffies,
L
Linus Torvalds 已提交
2682
	},
2683
	{ }
L
Linus Torvalds 已提交
2684 2685
};

2686
struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
2687 2688 2689 2690 2691 2692
{
	struct ctl_table *table;

	table = kmemdup(ipv6_route_table_template,
			sizeof(ipv6_route_table_template),
			GFP_KERNEL);
2693 2694 2695

	if (table) {
		table[0].data = &net->ipv6.sysctl.flush_delay;
2696
		table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
2697 2698 2699 2700 2701 2702 2703
		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;
2704
		table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2705 2706
	}

2707 2708
	return table;
}
L
Linus Torvalds 已提交
2709 2710
#endif

2711
static int __net_init ip6_route_net_init(struct net *net)
2712
{
2713
	int ret = -ENOMEM;
2714

2715 2716
	memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
	       sizeof(net->ipv6.ip6_dst_ops));
2717

2718 2719 2720
	if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
		goto out_ip6_dst_ops;

2721 2722 2723 2724
	net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
					   sizeof(*net->ipv6.ip6_null_entry),
					   GFP_KERNEL);
	if (!net->ipv6.ip6_null_entry)
2725
		goto out_ip6_dst_entries;
2726
	net->ipv6.ip6_null_entry->dst.path =
2727
		(struct dst_entry *)net->ipv6.ip6_null_entry;
2728
	net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2729 2730
	dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
			 ip6_template_metrics, true);
2731 2732 2733 2734 2735

#ifdef CONFIG_IPV6_MULTIPLE_TABLES
	net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
					       sizeof(*net->ipv6.ip6_prohibit_entry),
					       GFP_KERNEL);
2736 2737
	if (!net->ipv6.ip6_prohibit_entry)
		goto out_ip6_null_entry;
2738
	net->ipv6.ip6_prohibit_entry->dst.path =
2739
		(struct dst_entry *)net->ipv6.ip6_prohibit_entry;
2740
	net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2741 2742
	dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
			 ip6_template_metrics, true);
2743 2744 2745 2746

	net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
					       sizeof(*net->ipv6.ip6_blk_hole_entry),
					       GFP_KERNEL);
2747 2748
	if (!net->ipv6.ip6_blk_hole_entry)
		goto out_ip6_prohibit_entry;
2749
	net->ipv6.ip6_blk_hole_entry->dst.path =
2750
		(struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
2751
	net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
2752 2753
	dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
			 ip6_template_metrics, true);
2754 2755
#endif

2756 2757 2758 2759 2760 2761 2762 2763 2764
	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;

2765 2766 2767 2768
#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
2769 2770
	net->ipv6.ip6_rt_gc_expire = 30*HZ;

2771 2772 2773
	ret = 0;
out:
	return ret;
2774

2775 2776 2777 2778 2779 2780
#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
2781 2782
out_ip6_dst_entries:
	dst_entries_destroy(&net->ipv6.ip6_dst_ops);
2783 2784
out_ip6_dst_ops:
	goto out;
2785 2786
}

2787
static void __net_exit ip6_route_net_exit(struct net *net)
2788 2789 2790 2791 2792
{
#ifdef CONFIG_PROC_FS
	proc_net_remove(net, "ipv6_route");
	proc_net_remove(net, "rt6_stats");
#endif
2793 2794 2795 2796 2797
	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
2798
	dst_entries_destroy(&net->ipv6.ip6_dst_ops);
2799 2800 2801 2802 2803 2804 2805
}

static struct pernet_operations ip6_route_net_ops = {
	.init = ip6_route_net_init,
	.exit = ip6_route_net_exit,
};

2806 2807 2808 2809 2810
static struct notifier_block ip6_route_dev_notifier = {
	.notifier_call = ip6_route_dev_notify,
	.priority = 0,
};

2811
int __init ip6_route_init(void)
L
Linus Torvalds 已提交
2812
{
2813 2814
	int ret;

2815 2816
	ret = -ENOMEM;
	ip6_dst_ops_template.kmem_cachep =
A
Alexey Dobriyan 已提交
2817
		kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
2818
				  SLAB_HWCACHE_ALIGN, NULL);
2819
	if (!ip6_dst_ops_template.kmem_cachep)
2820
		goto out;
2821

2822
	ret = dst_entries_init(&ip6_dst_blackhole_ops);
2823
	if (ret)
2824 2825
		goto out_kmem_cache;

2826 2827 2828 2829
	ret = register_pernet_subsys(&ip6_route_net_ops);
	if (ret)
		goto out_dst_entries;

2830 2831
	ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;

2832 2833 2834
	/* 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 */
2835
	init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
2836 2837
	init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
  #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2838
	init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
2839
	init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2840
	init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
2841 2842
	init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
  #endif
2843 2844
	ret = fib6_init();
	if (ret)
2845
		goto out_register_subsys;
2846 2847 2848

	ret = xfrm6_init();
	if (ret)
2849
		goto out_fib6_init;
2850

2851 2852 2853
	ret = fib6_rules_init();
	if (ret)
		goto xfrm6_init;
2854

2855 2856 2857 2858 2859
	ret = -ENOBUFS;
	if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL) ||
	    __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL) ||
	    __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL))
		goto fib6_rules_init;
2860

2861
	ret = register_netdevice_notifier(&ip6_route_dev_notifier);
2862 2863
	if (ret)
		goto fib6_rules_init;
2864

2865 2866 2867 2868 2869 2870 2871 2872 2873
out:
	return ret;

fib6_rules_init:
	fib6_rules_cleanup();
xfrm6_init:
	xfrm6_fini();
out_fib6_init:
	fib6_gc_cleanup();
2874 2875
out_register_subsys:
	unregister_pernet_subsys(&ip6_route_net_ops);
2876 2877
out_dst_entries:
	dst_entries_destroy(&ip6_dst_blackhole_ops);
2878
out_kmem_cache:
2879
	kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
2880
	goto out;
L
Linus Torvalds 已提交
2881 2882 2883 2884
}

void ip6_route_cleanup(void)
{
2885
	unregister_netdevice_notifier(&ip6_route_dev_notifier);
T
Thomas Graf 已提交
2886
	fib6_rules_cleanup();
L
Linus Torvalds 已提交
2887 2888
	xfrm6_fini();
	fib6_gc_cleanup();
2889
	unregister_pernet_subsys(&ip6_route_net_ops);
2890
	dst_entries_destroy(&ip6_dst_blackhole_ops);
2891
	kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
L
Linus Torvalds 已提交
2892
}