route.c 59.3 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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 *
 *	$Id: route.c,v 1.56 2001/10/31 21:55:55 davem Exp $
 *
 *	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>
#include <linux/init.h>
#include <linux/if_arp.h>

#ifdef 	CONFIG_PROC_FS
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#endif

#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

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#define CLONE_OFFLINK_ROUTE 0
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static int ip6_rt_max_size = 4096;
static int ip6_rt_gc_min_interval = HZ / 2;
static int ip6_rt_gc_timeout = 60*HZ;
int ip6_rt_gc_interval = 30*HZ;
static int ip6_rt_gc_elasticity = 9;
static int ip6_rt_mtu_expires = 10*60*HZ;
static int ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;

static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
static struct dst_entry	*ip6_dst_check(struct dst_entry *dst, u32 cookie);
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);
static int		 ip6_dst_gc(void);

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

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static struct dst_ops ip6_dst_ops = {
	.family			=	AF_INET6,
	.protocol		=	__constant_htons(ETH_P_IPV6),
	.gc			=	ip6_dst_gc,
	.gc_thresh		=	1024,
	.check			=	ip6_dst_check,
	.destroy		=	ip6_dst_destroy,
	.ifdown			=	ip6_dst_ifdown,
	.negative_advice	=	ip6_negative_advice,
	.link_failure		=	ip6_link_failure,
	.update_pmtu		=	ip6_rt_update_pmtu,
	.entry_size		=	sizeof(struct rt6_info),
};

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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,
	.protocol		=	__constant_htons(ETH_P_IPV6),
	.destroy		=	ip6_dst_destroy,
	.check			=	ip6_dst_check,
	.update_pmtu		=	ip6_rt_blackhole_update_pmtu,
	.entry_size		=	sizeof(struct rt6_info),
};

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struct rt6_info ip6_null_entry = {
	.u = {
		.dst = {
			.__refcnt	= ATOMIC_INIT(1),
			.__use		= 1,
			.dev		= &loopback_dev,
			.obsolete	= -1,
			.error		= -ENETUNREACH,
			.metrics	= { [RTAX_HOPLIMIT - 1] = 255, },
			.input		= ip6_pkt_discard,
			.output		= ip6_pkt_discard_out,
			.ops		= &ip6_dst_ops,
			.path		= (struct dst_entry*)&ip6_null_entry,
		}
	},
	.rt6i_flags	= (RTF_REJECT | RTF_NONEXTHOP),
	.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);
static int ip6_pkt_blk_hole(struct sk_buff *skb);

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struct rt6_info ip6_prohibit_entry = {
	.u = {
		.dst = {
			.__refcnt	= ATOMIC_INIT(1),
			.__use		= 1,
			.dev		= &loopback_dev,
			.obsolete	= -1,
			.error		= -EACCES,
			.metrics	= { [RTAX_HOPLIMIT - 1] = 255, },
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			.input		= ip6_pkt_prohibit,
			.output		= ip6_pkt_prohibit_out,
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			.ops		= &ip6_dst_ops,
			.path		= (struct dst_entry*)&ip6_prohibit_entry,
		}
	},
	.rt6i_flags	= (RTF_REJECT | RTF_NONEXTHOP),
	.rt6i_metric	= ~(u32) 0,
	.rt6i_ref	= ATOMIC_INIT(1),
};

struct rt6_info ip6_blk_hole_entry = {
	.u = {
		.dst = {
			.__refcnt	= ATOMIC_INIT(1),
			.__use		= 1,
			.dev		= &loopback_dev,
			.obsolete	= -1,
			.error		= -EINVAL,
			.metrics	= { [RTAX_HOPLIMIT - 1] = 255, },
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			.input		= ip6_pkt_blk_hole,
			.output		= ip6_pkt_blk_hole,
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			.ops		= &ip6_dst_ops,
			.path		= (struct dst_entry*)&ip6_blk_hole_entry,
		}
	},
	.rt6i_flags	= (RTF_REJECT | RTF_NONEXTHOP),
	.rt6i_metric	= ~(u32) 0,
	.rt6i_ref	= ATOMIC_INIT(1),
};

#endif

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/* allocate dst with ip6_dst_ops */
static __inline__ struct rt6_info *ip6_dst_alloc(void)
{
	return (struct rt6_info *)dst_alloc(&ip6_dst_ops);
}

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

	if (idev != NULL) {
		rt->rt6i_idev = NULL;
		in6_dev_put(idev);
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	}
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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;

	if (dev != &loopback_dev && idev != NULL && idev->dev == dev) {
		struct inet6_dev *loopback_idev = in6_dev_get(&loopback_dev);
		if (loopback_idev != NULL) {
			rt->rt6i_idev = loopback_idev;
			in6_dev_put(idev);
		}
	}
}

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

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static inline int rt6_need_strict(struct in6_addr *daddr)
{
	return (ipv6_addr_type(daddr) &
		(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
}

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

static __inline__ struct rt6_info *rt6_device_match(struct rt6_info *rt,
						    int oif,
						    int strict)
{
	struct rt6_info *local = NULL;
	struct rt6_info *sprt;

	if (oif) {
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		for (sprt = rt; sprt; sprt = sprt->u.dst.rt6_next) {
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			struct net_device *dev = sprt->rt6i_dev;
			if (dev->ifindex == oif)
				return sprt;
			if (dev->flags & IFF_LOOPBACK) {
				if (sprt->rt6i_idev == NULL ||
				    sprt->rt6i_idev->dev->ifindex != oif) {
					if (strict && oif)
						continue;
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					if (local && (!oif ||
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						      local->rt6i_idev->dev->ifindex == oif))
						continue;
				}
				local = sprt;
			}
		}

		if (local)
			return local;

		if (strict)
			return &ip6_null_entry;
	}
	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)
{
	return;
}
#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;
	int m = 0;
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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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		else if (!(neigh->nud_state & NUD_FAILED))
			m = 1;
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		read_unlock_bh(&neigh->lock);
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	}
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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;
	     rt = rt->u.dst.rt6_next)
		match = find_match(rt, oif, strict, &mpri, match);
	for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
	     rt = rt->u.dst.rt6_next)
		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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	RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n",
		  __FUNCTION__, 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)) {
		struct rt6_info *next = rt0->u.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",
		  __FUNCTION__, match);
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	return (match ? match : &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)
{
	struct route_info *rinfo = (struct route_info *) opt;
	struct in6_addr prefix_buf, *prefix;
	unsigned int pref;
	u32 lifetime;
	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)
		pref = ICMPV6_ROUTER_PREF_MEDIUM;

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	lifetime = ntohl(rinfo->lifetime);
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	if (lifetime == 0xffffffff) {
		/* infinity */
	} else if (lifetime > 0x7fffffff/HZ) {
		/* Avoid arithmetic overflow */
		lifetime = 0x7fffffff/HZ - 1;
	}

	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;
	}

	rt = rt6_get_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex);

	if (rt && !lifetime) {
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		ip6_del_rt(rt);
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		rt = NULL;
	}

	if (!rt && lifetime)
		rt = rt6_add_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
					pref);
	else if (rt)
		rt->rt6i_flags = RTF_ROUTEINFO |
				 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);

	if (rt) {
		if (lifetime == 0xffffffff) {
			rt->rt6i_flags &= ~RTF_EXPIRES;
		} else {
			rt->rt6i_expires = jiffies + HZ * lifetime;
			rt->rt6i_flags |= RTF_EXPIRES;
		}
		dst_release(&rt->u.dst);
	}
	return 0;
}
#endif

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#define BACKTRACK(saddr) \
do { \
	if (rt == &ip6_null_entry) { \
		struct fib6_node *pn; \
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		while (1) { \
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			if (fn->fn_flags & RTN_TL_ROOT) \
				goto out; \
			pn = fn->parent; \
			if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
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				fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
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			else \
				fn = pn; \
			if (fn->fn_flags & RTN_RTINFO) \
				goto restart; \
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		} \
	} \
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} while(0)
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static struct rt6_info *ip6_pol_route_lookup(struct fib6_table *table,
					     struct flowi *fl, int flags)
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{
	struct fib6_node *fn;
	struct rt6_info *rt;

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	read_lock_bh(&table->tb6_lock);
	fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
restart:
	rt = fn->leaf;
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	rt = rt6_device_match(rt, fl->oif, flags);
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	BACKTRACK(&fl->fl6_src);
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out:
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	dst_hold(&rt->u.dst);
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	read_unlock_bh(&table->tb6_lock);
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	rt->u.dst.lastuse = jiffies;
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	rt->u.dst.__use++;

	return rt;

}

struct rt6_info *rt6_lookup(struct in6_addr *daddr, struct in6_addr *saddr,
			    int oif, int strict)
{
	struct flowi fl = {
		.oif = oif,
		.nl_u = {
			.ip6_u = {
				.daddr = *daddr,
			},
		},
	};
	struct dst_entry *dst;
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	int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
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	if (saddr) {
		memcpy(&fl.fl6_src, saddr, sizeof(*saddr));
		flags |= RT6_LOOKUP_F_HAS_SADDR;
	}

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582 583 584 585 586 587
	dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_lookup);
	if (dst->error == 0)
		return (struct rt6_info *) dst;

	dst_release(dst);

L
Linus Torvalds 已提交
588 589 590
	return NULL;
}

591 592
EXPORT_SYMBOL(rt6_lookup);

T
Thomas Graf 已提交
593
/* ip6_ins_rt is called with FREE table->tb6_lock.
L
Linus Torvalds 已提交
594 595 596 597 598
   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.
 */

599
static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
L
Linus Torvalds 已提交
600 601
{
	int err;
T
Thomas Graf 已提交
602
	struct fib6_table *table;
L
Linus Torvalds 已提交
603

T
Thomas Graf 已提交
604 605
	table = rt->rt6i_table;
	write_lock_bh(&table->tb6_lock);
606
	err = fib6_add(&table->tb6_root, rt, info);
T
Thomas Graf 已提交
607
	write_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
608 609 610 611

	return err;
}

612 613
int ip6_ins_rt(struct rt6_info *rt)
{
614
	return __ip6_ins_rt(rt, NULL);
615 616
}

617 618
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
619 620 621 622 623 624 625 626 627 628
{
	struct rt6_info *rt;

	/*
	 *	Clone the route.
	 */

	rt = ip6_rt_copy(ort);

	if (rt) {
629 630 631 632
		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
633
			ipv6_addr_copy(&rt->rt6i_gateway, daddr);
634
		}
L
Linus Torvalds 已提交
635

636
		ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
L
Linus Torvalds 已提交
637 638 639 640 641 642 643 644 645 646 647 648 649
		rt->rt6i_dst.plen = 128;
		rt->rt6i_flags |= RTF_CACHE;
		rt->u.dst.flags |= DST_HOST;

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

		rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);

650
	}
L
Linus Torvalds 已提交
651

652 653
	return rt;
}
L
Linus Torvalds 已提交
654

655 656 657 658 659 660 661 662 663 664 665 666 667
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;
		rt->u.dst.flags |= DST_HOST;
		rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop);
	}
	return rt;
}

A
Adrian Bunk 已提交
668 669
static struct rt6_info *ip6_pol_route_input(struct fib6_table *table,
					    struct flowi *fl, int flags)
L
Linus Torvalds 已提交
670 671
{
	struct fib6_node *fn;
672
	struct rt6_info *rt, *nrt;
T
Thomas Graf 已提交
673
	int strict = 0;
L
Linus Torvalds 已提交
674
	int attempts = 3;
675
	int err;
676
	int reachable = ipv6_devconf.forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
L
Linus Torvalds 已提交
677

678
	strict |= flags & RT6_LOOKUP_F_IFACE;
L
Linus Torvalds 已提交
679 680

relookup:
T
Thomas Graf 已提交
681
	read_lock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
682

683
restart_2:
T
Thomas Graf 已提交
684
	fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
L
Linus Torvalds 已提交
685 686

restart:
687
	rt = rt6_select(fn, fl->iif, strict | reachable);
688
	BACKTRACK(&fl->fl6_src);
689 690
	if (rt == &ip6_null_entry ||
	    rt->rt6i_flags & RTF_CACHE)
691
		goto out;
L
Linus Torvalds 已提交
692

693
	dst_hold(&rt->u.dst);
T
Thomas Graf 已提交
694
	read_unlock_bh(&table->tb6_lock);
695

696
	if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
T
Thomas Graf 已提交
697
		nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
698 699
	else {
#if CLONE_OFFLINK_ROUTE
T
Thomas Graf 已提交
700
		nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
701 702 703 704
#else
		goto out2;
#endif
	}
705

706 707
	dst_release(&rt->u.dst);
	rt = nrt ? : &ip6_null_entry;
L
Linus Torvalds 已提交
708

709 710
	dst_hold(&rt->u.dst);
	if (nrt) {
711
		err = ip6_ins_rt(nrt);
712
		if (!err)
L
Linus Torvalds 已提交
713 714 715
			goto out2;
	}

716 717 718 719
	if (--attempts <= 0)
		goto out2;

	/*
T
Thomas Graf 已提交
720
	 * Race condition! In the gap, when table->tb6_lock was
721 722 723 724 725 726
	 * released someone could insert this route.  Relookup.
	 */
	dst_release(&rt->u.dst);
	goto relookup;

out:
727 728 729 730
	if (reachable) {
		reachable = 0;
		goto restart_2;
	}
731
	dst_hold(&rt->u.dst);
T
Thomas Graf 已提交
732
	read_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
733 734 735
out2:
	rt->u.dst.lastuse = jiffies;
	rt->u.dst.__use++;
T
Thomas Graf 已提交
736 737

	return rt;
L
Linus Torvalds 已提交
738 739
}

T
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740 741
void ip6_route_input(struct sk_buff *skb)
{
742
	struct ipv6hdr *iph = ipv6_hdr(skb);
743
	int flags = RT6_LOOKUP_F_HAS_SADDR;
T
Thomas Graf 已提交
744 745 746 747 748 749
	struct flowi fl = {
		.iif = skb->dev->ifindex,
		.nl_u = {
			.ip6_u = {
				.daddr = iph->daddr,
				.saddr = iph->saddr,
A
Al Viro 已提交
750
				.flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK,
T
Thomas Graf 已提交
751 752
			},
		},
753
		.mark = skb->mark,
T
Thomas Graf 已提交
754 755
		.proto = iph->nexthdr,
	};
756 757 758

	if (rt6_need_strict(&iph->daddr))
		flags |= RT6_LOOKUP_F_IFACE;
T
Thomas Graf 已提交
759 760 761 762 763 764

	skb->dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_input);
}

static struct rt6_info *ip6_pol_route_output(struct fib6_table *table,
					     struct flowi *fl, int flags)
L
Linus Torvalds 已提交
765 766
{
	struct fib6_node *fn;
767
	struct rt6_info *rt, *nrt;
T
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768
	int strict = 0;
L
Linus Torvalds 已提交
769
	int attempts = 3;
770
	int err;
771
	int reachable = ipv6_devconf.forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
L
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772

773
	strict |= flags & RT6_LOOKUP_F_IFACE;
L
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774 775

relookup:
T
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776
	read_lock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
777

778
restart_2:
T
Thomas Graf 已提交
779
	fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
L
Linus Torvalds 已提交
780 781

restart:
782
	rt = rt6_select(fn, fl->oif, strict | reachable);
783
	BACKTRACK(&fl->fl6_src);
784 785
	if (rt == &ip6_null_entry ||
	    rt->rt6i_flags & RTF_CACHE)
L
Linus Torvalds 已提交
786 787
		goto out;

788
	dst_hold(&rt->u.dst);
T
Thomas Graf 已提交
789
	read_unlock_bh(&table->tb6_lock);
790

791
	if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
792
		nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
793 794 795 796 797 798 799
	else {
#if CLONE_OFFLINK_ROUTE
		nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
#else
		goto out2;
#endif
	}
L
Linus Torvalds 已提交
800

801 802
	dst_release(&rt->u.dst);
	rt = nrt ? : &ip6_null_entry;
L
Linus Torvalds 已提交
803

804 805
	dst_hold(&rt->u.dst);
	if (nrt) {
806
		err = ip6_ins_rt(nrt);
807
		if (!err)
L
Linus Torvalds 已提交
808 809
			goto out2;
	}
810

811 812 813 814
	if (--attempts <= 0)
		goto out2;

	/*
T
Thomas Graf 已提交
815
	 * Race condition! In the gap, when table->tb6_lock was
816 817 818 819 820 821
	 * released someone could insert this route.  Relookup.
	 */
	dst_release(&rt->u.dst);
	goto relookup;

out:
822 823 824 825
	if (reachable) {
		reachable = 0;
		goto restart_2;
	}
826
	dst_hold(&rt->u.dst);
T
Thomas Graf 已提交
827
	read_unlock_bh(&table->tb6_lock);
L
Linus Torvalds 已提交
828 829 830
out2:
	rt->u.dst.lastuse = jiffies;
	rt->u.dst.__use++;
T
Thomas Graf 已提交
831 832 833 834 835 836 837 838
	return rt;
}

struct dst_entry * ip6_route_output(struct sock *sk, struct flowi *fl)
{
	int flags = 0;

	if (rt6_need_strict(&fl->fl6_dst))
839
		flags |= RT6_LOOKUP_F_IFACE;
T
Thomas Graf 已提交
840

841 842 843
	if (!ipv6_addr_any(&fl->fl6_src))
		flags |= RT6_LOOKUP_F_HAS_SADDR;

T
Thomas Graf 已提交
844
	return fib6_rule_lookup(fl, flags, ip6_pol_route_output);
L
Linus Torvalds 已提交
845 846
}

847
EXPORT_SYMBOL(ip6_route_output);
L
Linus Torvalds 已提交
848

849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896
static int ip6_blackhole_output(struct sk_buff *skb)
{
	kfree_skb(skb);
	return 0;
}

int ip6_dst_blackhole(struct sock *sk, struct dst_entry **dstp, struct flowi *fl)
{
	struct rt6_info *ort = (struct rt6_info *) *dstp;
	struct rt6_info *rt = (struct rt6_info *)
		dst_alloc(&ip6_dst_blackhole_ops);
	struct dst_entry *new = NULL;

	if (rt) {
		new = &rt->u.dst;

		atomic_set(&new->__refcnt, 1);
		new->__use = 1;
		new->input = ip6_blackhole_output;
		new->output = ip6_blackhole_output;

		memcpy(new->metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
		new->dev = ort->u.dst.dev;
		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);
	}

	dst_release(*dstp);
	*dstp = new;
	return (new ? 0 : -ENOMEM);
}
EXPORT_SYMBOL_GPL(ip6_dst_blackhole);

L
Linus Torvalds 已提交
897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918
/*
 *	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;

	if (rt && rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie))
		return dst;

	return NULL;
}

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

	if (rt) {
		if (rt->rt6i_flags & RTF_CACHE)
919
			ip6_del_rt(rt);
L
Linus Torvalds 已提交
920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952
		else
			dst_release(dst);
	}
	return NULL;
}

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

	icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0, skb->dev);

	rt = (struct rt6_info *) skb->dst;
	if (rt) {
		if (rt->rt6i_flags&RTF_CACHE) {
			dst_set_expires(&rt->u.dst, 0);
			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) {
			mtu = IPV6_MIN_MTU;
			dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
		}
		dst->metrics[RTAX_MTU-1] = mtu;
953
		call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
L
Linus Torvalds 已提交
954 955 956 957 958 959 960 961 962 963 964 965 966
	}
}

static int ipv6_get_mtu(struct net_device *dev);

static inline unsigned int ipv6_advmss(unsigned int mtu)
{
	mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);

	if (mtu < ip6_rt_min_advmss)
		mtu = ip6_rt_min_advmss;

	/*
967 968 969
	 * 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
970 971 972 973 974 975 976
	 * rely only on pmtu discovery"
	 */
	if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
		mtu = IPV6_MAXPLEN;
	return mtu;
}

977
static struct dst_entry *ndisc_dst_gc_list;
A
Adrian Bunk 已提交
978
static DEFINE_SPINLOCK(ndisc_lock);
979

980
struct dst_entry *ndisc_dst_alloc(struct net_device *dev,
L
Linus Torvalds 已提交
981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012
				  struct neighbour *neigh,
				  struct in6_addr *addr,
				  int (*output)(struct sk_buff *))
{
	struct rt6_info *rt;
	struct inet6_dev *idev = in6_dev_get(dev);

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

	rt = ip6_dst_alloc();
	if (unlikely(rt == NULL)) {
		in6_dev_put(idev);
		goto out;
	}

	dev_hold(dev);
	if (neigh)
		neigh_hold(neigh);
	else
		neigh = ndisc_get_neigh(dev, addr);

	rt->rt6i_dev	  = dev;
	rt->rt6i_idev     = idev;
	rt->rt6i_nexthop  = neigh;
	atomic_set(&rt->u.dst.__refcnt, 1);
	rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255;
	rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
	rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
	rt->u.dst.output  = output;

#if 0	/* there's no chance to use these for ndisc */
1013 1014
	rt->u.dst.flags   = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST
				? DST_HOST
L
Linus Torvalds 已提交
1015 1016 1017 1018 1019
				: 0;
	ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
	rt->rt6i_dst.plen = 128;
#endif

1020
	spin_lock_bh(&ndisc_lock);
L
Linus Torvalds 已提交
1021 1022
	rt->u.dst.next = ndisc_dst_gc_list;
	ndisc_dst_gc_list = &rt->u.dst;
1023
	spin_unlock_bh(&ndisc_lock);
L
Linus Torvalds 已提交
1024 1025 1026 1027

	fib6_force_start_gc();

out:
1028
	return &rt->u.dst;
L
Linus Torvalds 已提交
1029 1030 1031 1032 1033 1034 1035 1036
}

int ndisc_dst_gc(int *more)
{
	struct dst_entry *dst, *next, **pprev;
	int freed;

	next = NULL;
1037
	freed = 0;
1038 1039

	spin_lock_bh(&ndisc_lock);
L
Linus Torvalds 已提交
1040
	pprev = &ndisc_dst_gc_list;
1041

L
Linus Torvalds 已提交
1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052
	while ((dst = *pprev) != NULL) {
		if (!atomic_read(&dst->__refcnt)) {
			*pprev = dst->next;
			dst_free(dst);
			freed++;
		} else {
			pprev = &dst->next;
			(*more)++;
		}
	}

1053 1054
	spin_unlock_bh(&ndisc_lock);

L
Linus Torvalds 已提交
1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114
	return freed;
}

static int ip6_dst_gc(void)
{
	static unsigned expire = 30*HZ;
	static unsigned long last_gc;
	unsigned long now = jiffies;

	if (time_after(last_gc + ip6_rt_gc_min_interval, now) &&
	    atomic_read(&ip6_dst_ops.entries) <= ip6_rt_max_size)
		goto out;

	expire++;
	fib6_run_gc(expire);
	last_gc = now;
	if (atomic_read(&ip6_dst_ops.entries) < ip6_dst_ops.gc_thresh)
		expire = ip6_rt_gc_timeout>>1;

out:
	expire -= expire>>ip6_rt_gc_elasticity;
	return (atomic_read(&ip6_dst_ops.entries) > ip6_rt_max_size);
}

/* 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!
 */

static int ipv6_get_mtu(struct net_device *dev)
{
	int mtu = IPV6_MIN_MTU;
	struct inet6_dev *idev;

	idev = in6_dev_get(dev);
	if (idev) {
		mtu = idev->cnf.mtu6;
		in6_dev_put(idev);
	}
	return mtu;
}

int ipv6_get_hoplimit(struct net_device *dev)
{
	int hoplimit = ipv6_devconf.hop_limit;
	struct inet6_dev *idev;

	idev = in6_dev_get(dev);
	if (idev) {
		hoplimit = idev->cnf.hop_limit;
		in6_dev_put(idev);
	}
	return hoplimit;
}

/*
 *
 */

1115
int ip6_route_add(struct fib6_config *cfg)
L
Linus Torvalds 已提交
1116 1117 1118 1119 1120
{
	int err;
	struct rt6_info *rt = NULL;
	struct net_device *dev = NULL;
	struct inet6_dev *idev = NULL;
T
Thomas Graf 已提交
1121
	struct fib6_table *table;
L
Linus Torvalds 已提交
1122 1123
	int addr_type;

1124
	if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
L
Linus Torvalds 已提交
1125 1126
		return -EINVAL;
#ifndef CONFIG_IPV6_SUBTREES
1127
	if (cfg->fc_src_len)
L
Linus Torvalds 已提交
1128 1129
		return -EINVAL;
#endif
1130
	if (cfg->fc_ifindex) {
L
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1131
		err = -ENODEV;
1132
		dev = dev_get_by_index(cfg->fc_ifindex);
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1133 1134 1135 1136 1137 1138 1139
		if (!dev)
			goto out;
		idev = in6_dev_get(dev);
		if (!idev)
			goto out;
	}

1140 1141
	if (cfg->fc_metric == 0)
		cfg->fc_metric = IP6_RT_PRIO_USER;
L
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1142

1143
	table = fib6_new_table(cfg->fc_table);
T
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1144 1145 1146 1147 1148
	if (table == NULL) {
		err = -ENOBUFS;
		goto out;
	}

L
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1149 1150 1151 1152 1153 1154 1155 1156
	rt = ip6_dst_alloc();

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

	rt->u.dst.obsolete = -1;
1157
	rt->rt6i_expires = jiffies + clock_t_to_jiffies(cfg->fc_expires);
L
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1158

1159 1160 1161 1162 1163
	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
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1164 1165 1166 1167 1168 1169 1170 1171

	if (addr_type & IPV6_ADDR_MULTICAST)
		rt->u.dst.input = ip6_mc_input;
	else
		rt->u.dst.input = ip6_forward;

	rt->u.dst.output = ip6_output;

1172 1173
	ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
	rt->rt6i_dst.plen = cfg->fc_dst_len;
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	if (rt->rt6i_dst.plen == 128)
	       rt->u.dst.flags = DST_HOST;

#ifdef CONFIG_IPV6_SUBTREES
1178 1179
	ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
	rt->rt6i_src.plen = cfg->fc_src_len;
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#endif

1182
	rt->rt6i_metric = cfg->fc_metric;
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	/* We cannot add true routes via loopback here,
	   they would result in kernel looping; promote them to reject routes
	 */
1187
	if ((cfg->fc_flags & RTF_REJECT) ||
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	    (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) {
		/* hold loopback dev/idev if we haven't done so. */
		if (dev != &loopback_dev) {
			if (dev) {
				dev_put(dev);
				in6_dev_put(idev);
			}
			dev = &loopback_dev;
			dev_hold(dev);
			idev = in6_dev_get(dev);
			if (!idev) {
				err = -ENODEV;
				goto out;
			}
		}
		rt->u.dst.output = ip6_pkt_discard_out;
		rt->u.dst.input = ip6_pkt_discard;
		rt->u.dst.error = -ENETUNREACH;
		rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
		goto install_route;
	}

1210
	if (cfg->fc_flags & RTF_GATEWAY) {
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		struct in6_addr *gw_addr;
		int gwa_type;

1214 1215
		gw_addr = &cfg->fc_gateway;
		ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
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		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;

1232
			grt = rt6_lookup(gw_addr, NULL, cfg->fc_ifindex, 1);
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1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263

			err = -EHOSTUNREACH;
			if (grt == NULL)
				goto out;
			if (dev) {
				if (dev != grt->rt6i_dev) {
					dst_release(&grt->u.dst);
					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;
			dst_release(&grt->u.dst);

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

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

1264
	if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
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		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;
		}
	}

1273
	rt->rt6i_flags = cfg->fc_flags;
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install_route:
1276 1277 1278 1279 1280 1281 1282 1283 1284
	if (cfg->fc_mx) {
		struct nlattr *nla;
		int remaining;

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

			if (type) {
				if (type > RTAX_MAX) {
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					err = -EINVAL;
					goto out;
				}
1288 1289

				rt->u.dst.metrics[type - 1] = nla_get_u32(nla);
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			}
		}
	}

	if (rt->u.dst.metrics[RTAX_HOPLIMIT-1] == 0)
		rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
	if (!rt->u.dst.metrics[RTAX_MTU-1])
		rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev);
	if (!rt->u.dst.metrics[RTAX_ADVMSS-1])
		rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
	rt->u.dst.dev = dev;
	rt->rt6i_idev = idev;
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	rt->rt6i_table = table;
1303
	return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
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out:
	if (dev)
		dev_put(dev);
	if (idev)
		in6_dev_put(idev);
	if (rt)
1311
		dst_free(&rt->u.dst);
L
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1312 1313 1314
	return err;
}

1315
static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
L
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1316 1317
{
	int err;
T
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1318
	struct fib6_table *table;
L
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1319

1320 1321 1322
	if (rt == &ip6_null_entry)
		return -ENOENT;

T
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1323 1324
	table = rt->rt6i_table;
	write_lock_bh(&table->tb6_lock);
L
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1325

1326
	err = fib6_del(rt, info);
L
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1327 1328
	dst_release(&rt->u.dst);

T
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1329
	write_unlock_bh(&table->tb6_lock);
L
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	return err;
}

1334 1335
int ip6_del_rt(struct rt6_info *rt)
{
1336
	return __ip6_del_rt(rt, NULL);
1337 1338
}

1339
static int ip6_route_del(struct fib6_config *cfg)
L
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{
T
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1341
	struct fib6_table *table;
L
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1342 1343 1344 1345
	struct fib6_node *fn;
	struct rt6_info *rt;
	int err = -ESRCH;

1346
	table = fib6_get_table(cfg->fc_table);
T
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	if (table == NULL)
		return err;

	read_lock_bh(&table->tb6_lock);
L
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1351

T
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	fn = fib6_locate(&table->tb6_root,
1353 1354
			 &cfg->fc_dst, cfg->fc_dst_len,
			 &cfg->fc_src, cfg->fc_src_len);
1355

L
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	if (fn) {
1357
		for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1358
			if (cfg->fc_ifindex &&
L
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			    (rt->rt6i_dev == NULL ||
1360
			     rt->rt6i_dev->ifindex != cfg->fc_ifindex))
L
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				continue;
1362 1363
			if (cfg->fc_flags & RTF_GATEWAY &&
			    !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
L
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1364
				continue;
1365
			if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
L
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				continue;
			dst_hold(&rt->u.dst);
T
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			read_unlock_bh(&table->tb6_lock);
L
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1369

1370
			return __ip6_del_rt(rt, &cfg->fc_nlinfo);
L
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		}
	}
T
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	read_unlock_bh(&table->tb6_lock);
L
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	return err;
}

/*
 *	Handle redirects
 */
1381 1382 1383 1384 1385 1386 1387 1388
struct ip6rd_flowi {
	struct flowi fl;
	struct in6_addr gateway;
};

static struct rt6_info *__ip6_route_redirect(struct fib6_table *table,
					     struct flowi *fl,
					     int flags)
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{
1390 1391
	struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl;
	struct rt6_info *rt;
1392
	struct fib6_node *fn;
T
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1393

L
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1394
	/*
1395 1396 1397 1398 1399 1400 1401 1402
	 * 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
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	 */

T
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1405
	read_lock_bh(&table->tb6_lock);
1406
	fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
1407
restart:
1408
	for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420
		/*
		 * 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;
1421
		if (fl->oif != rt->rt6i_dev->ifindex)
1422
			continue;
1423
		if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1424 1425 1426
			continue;
		break;
	}
1427

1428
	if (!rt)
1429
		rt = &ip6_null_entry;
1430 1431
	BACKTRACK(&fl->fl6_src);
out:
1432 1433
	dst_hold(&rt->u.dst);

T
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1434
	read_unlock_bh(&table->tb6_lock);
1435

1436 1437 1438 1439 1440 1441 1442 1443
	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)
{
1444
	int flags = RT6_LOOKUP_F_HAS_SADDR;
1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456
	struct ip6rd_flowi rdfl = {
		.fl = {
			.oif = dev->ifindex,
			.nl_u = {
				.ip6_u = {
					.daddr = *dest,
					.saddr = *src,
				},
			},
		},
		.gateway = *gateway,
	};
1457 1458 1459

	if (rt6_need_strict(dest))
		flags |= RT6_LOOKUP_F_IFACE;
1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473

	return (struct rt6_info *)fib6_rule_lookup((struct flowi *)&rdfl, flags, __ip6_route_redirect);
}

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;

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

	if (rt == &ip6_null_entry) {
L
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1474 1475 1476
		if (net_ratelimit())
			printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
			       "for redirect target\n");
1477
		goto out;
L
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1478 1479 1480 1481 1482 1483
	}

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

1484
	neigh_update(neigh, lladdr, NUD_STALE,
L
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1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519
		     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
	 */
	dst_confirm(&rt->u.dst);

	/* Duplicate redirect: silently ignore. */
	if (neigh == rt->u.dst.neighbour)
		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;
	nrt->u.dst.flags |= DST_HOST;

	ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
	nrt->rt6i_nexthop = neigh_clone(neigh);
	/* Reset pmtu, it may be better */
	nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev);
	nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&nrt->u.dst));

1520
	if (ip6_ins_rt(nrt))
L
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1521 1522
		goto out;

1523 1524 1525 1526
	netevent.old = &rt->u.dst;
	netevent.new = &nrt->u.dst;
	call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);

L
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1527
	if (rt->rt6i_flags&RTF_CACHE) {
1528
		ip6_del_rt(rt);
L
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1529 1530 1531 1532
		return;
	}

out:
1533
	dst_release(&rt->u.dst);
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	return;
}

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

void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr,
			struct net_device *dev, u32 pmtu)
{
	struct rt6_info *rt, *nrt;
	int allfrag = 0;

	rt = rt6_lookup(daddr, saddr, dev->ifindex, 0);
	if (rt == NULL)
		return;

	if (pmtu >= dst_mtu(&rt->u.dst))
		goto out;

	if (pmtu < IPV6_MIN_MTU) {
		/*
1557
		 * According to RFC2460, PMTU is set to the IPv6 Minimum Link
L
Linus Torvalds 已提交
1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590
		 * 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
	 */
	dst_confirm(&rt->u.dst);

	/* 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) {
		rt->u.dst.metrics[RTAX_MTU-1] = pmtu;
		if (allfrag)
			rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
		dst_set_expires(&rt->u.dst, ip6_rt_mtu_expires);
		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.
	 */
1591
	if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
1592
		nrt = rt6_alloc_cow(rt, daddr, saddr);
1593 1594
	else
		nrt = rt6_alloc_clone(rt, daddr);
1595

1596
	if (nrt) {
1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609
		nrt->u.dst.metrics[RTAX_MTU-1] = pmtu;
		if (allfrag)
			nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;

		/* 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.
		 */
		dst_set_expires(&nrt->u.dst, ip6_rt_mtu_expires);
		nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;

1610
		ip6_ins_rt(nrt);
L
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1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628
	}
out:
	dst_release(&rt->u.dst);
}

/*
 *	Misc support functions
 */

static struct rt6_info * ip6_rt_copy(struct rt6_info *ort)
{
	struct rt6_info *rt = ip6_dst_alloc();

	if (rt) {
		rt->u.dst.input = ort->u.dst.input;
		rt->u.dst.output = ort->u.dst.output;

		memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
1629
		rt->u.dst.error = ort->u.dst.error;
L
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1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646
		rt->u.dst.dev = ort->u.dst.dev;
		if (rt->u.dst.dev)
			dev_hold(rt->u.dst.dev);
		rt->rt6i_idev = ort->rt6i_idev;
		if (rt->rt6i_idev)
			in6_dev_hold(rt->rt6i_idev);
		rt->u.dst.lastuse = jiffies;
		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
1647
		rt->rt6i_table = ort->rt6i_table;
L
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1648 1649 1650 1651
	}
	return rt;
}

1652 1653 1654 1655 1656 1657
#ifdef CONFIG_IPV6_ROUTE_INFO
static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
					   struct in6_addr *gwaddr, int ifindex)
{
	struct fib6_node *fn;
	struct rt6_info *rt = NULL;
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	struct fib6_table *table;

	table = fib6_get_table(RT6_TABLE_INFO);
	if (table == NULL)
		return NULL;
1663

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	write_lock_bh(&table->tb6_lock);
	fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1666 1667 1668
	if (!fn)
		goto out;

1669
	for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1670 1671 1672 1673 1674 1675 1676 1677 1678 1679
		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;
		dst_hold(&rt->u.dst);
		break;
	}
out:
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	write_unlock_bh(&table->tb6_lock);
1681 1682 1683 1684 1685 1686 1687
	return rt;
}

static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
					   struct in6_addr *gwaddr, int ifindex,
					   unsigned pref)
{
1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698
	struct fib6_config cfg = {
		.fc_table	= RT6_TABLE_INFO,
		.fc_metric	= 1024,
		.fc_ifindex	= ifindex,
		.fc_dst_len	= prefixlen,
		.fc_flags	= RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
				  RTF_UP | RTF_PREF(pref),
	};

	ipv6_addr_copy(&cfg.fc_dst, prefix);
	ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1699

1700 1701
	/* We should treat it as a default route if prefix length is 0. */
	if (!prefixlen)
1702
		cfg.fc_flags |= RTF_DEFAULT;
1703

1704
	ip6_route_add(&cfg);
1705 1706 1707 1708 1709

	return rt6_get_route_info(prefix, prefixlen, gwaddr, ifindex);
}
#endif

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struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev)
1711
{
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	struct rt6_info *rt;
T
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	struct fib6_table *table;
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	table = fib6_get_table(RT6_TABLE_DFLT);
	if (table == NULL)
		return NULL;
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T
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	write_lock_bh(&table->tb6_lock);
1720
	for (rt = table->tb6_root.leaf; rt; rt=rt->u.dst.rt6_next) {
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		if (dev == rt->rt6i_dev &&
1722
		    ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
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		    ipv6_addr_equal(&rt->rt6i_gateway, addr))
			break;
	}
	if (rt)
		dst_hold(&rt->u.dst);
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	write_unlock_bh(&table->tb6_lock);
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	return rt;
}

struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr,
1733 1734
				     struct net_device *dev,
				     unsigned int pref)
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{
1736 1737 1738 1739 1740 1741 1742
	struct fib6_config cfg = {
		.fc_table	= RT6_TABLE_DFLT,
		.fc_metric	= 1024,
		.fc_ifindex	= dev->ifindex,
		.fc_flags	= RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
				  RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
	};
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1744
	ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
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1746
	ip6_route_add(&cfg);
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	return rt6_get_dflt_router(gwaddr, dev);
}

void rt6_purge_dflt_routers(void)
{
	struct rt6_info *rt;
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	struct fib6_table *table;

	/* NOTE: Keep consistent with rt6_get_dflt_router */
	table = fib6_get_table(RT6_TABLE_DFLT);
	if (table == NULL)
		return;
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restart:
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	read_lock_bh(&table->tb6_lock);
1763
	for (rt = table->tb6_root.leaf; rt; rt = rt->u.dst.rt6_next) {
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		if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
			dst_hold(&rt->u.dst);
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			read_unlock_bh(&table->tb6_lock);
1767
			ip6_del_rt(rt);
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			goto restart;
		}
	}
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	read_unlock_bh(&table->tb6_lock);
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}

1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791
static void rtmsg_to_fib6_config(struct in6_rtmsg *rtmsg,
				 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;

	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);
}

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int ipv6_route_ioctl(unsigned int cmd, void __user *arg)
{
1794
	struct fib6_config cfg;
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	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;
1807 1808 1809

		rtmsg_to_fib6_config(&rtmsg, &cfg);

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		rtnl_lock();
		switch (cmd) {
		case SIOCADDRT:
1813
			err = ip6_route_add(&cfg);
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			break;
		case SIOCDELRT:
1816
			err = ip6_route_del(&cfg);
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			break;
		default:
			err = -EINVAL;
		}
		rtnl_unlock();

		return err;
1824
	}
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	return -EINVAL;
}

/*
 *	Drop the packet on the floor
 */

1833 1834
static inline int ip6_pkt_drop(struct sk_buff *skb, int code,
			       int ipstats_mib_noroutes)
L
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{
1836 1837 1838
	int type;
	switch (ipstats_mib_noroutes) {
	case IPSTATS_MIB_INNOROUTES:
1839
		type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
1840 1841 1842 1843 1844 1845 1846 1847 1848
		if (type == IPV6_ADDR_ANY || type == IPV6_ADDR_RESERVED) {
			IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INADDRERRORS);
			break;
		}
		/* FALLTHROUGH */
	case IPSTATS_MIB_OUTNOROUTES:
		IP6_INC_STATS(ip6_dst_idev(skb->dst), ipstats_mib_noroutes);
		break;
	}
1849
	icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0, skb->dev);
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	kfree_skb(skb);
	return 0;
}

1854 1855
static int ip6_pkt_discard(struct sk_buff *skb)
{
1856
	return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
1857 1858
}

1859
static int ip6_pkt_discard_out(struct sk_buff *skb)
L
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{
	skb->dev = skb->dst->dev;
1862
	return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
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}

1865 1866
#ifdef CONFIG_IPV6_MULTIPLE_TABLES

1867 1868
static int ip6_pkt_prohibit(struct sk_buff *skb)
{
1869
	return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
1870 1871 1872 1873 1874
}

static int ip6_pkt_prohibit_out(struct sk_buff *skb)
{
	skb->dev = skb->dst->dev;
1875
	return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
1876 1877 1878 1879 1880 1881 1882 1883
}

static int ip6_pkt_blk_hole(struct sk_buff *skb)
{
	kfree_skb(skb);
	return 0;
}

1884 1885
#endif

L
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/*
 *	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)
{
	struct rt6_info *rt = ip6_dst_alloc();

	if (rt == NULL)
		return ERR_PTR(-ENOMEM);

	dev_hold(&loopback_dev);
	in6_dev_hold(idev);

	rt->u.dst.flags = DST_HOST;
	rt->u.dst.input = ip6_input;
	rt->u.dst.output = ip6_output;
	rt->rt6i_dev = &loopback_dev;
	rt->rt6i_idev = idev;
	rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
	rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
	rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
	rt->u.dst.obsolete = -1;

	rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
1913 1914 1915
	if (anycast)
		rt->rt6i_flags |= RTF_ANYCAST;
	else
L
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		rt->rt6i_flags |= RTF_LOCAL;
	rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
	if (rt->rt6i_nexthop == NULL) {
1919
		dst_free(&rt->u.dst);
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		return ERR_PTR(-ENOMEM);
	}

	ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
	rt->rt6i_dst.plen = 128;
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	rt->rt6i_table = fib6_get_table(RT6_TABLE_LOCAL);
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1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943

	atomic_set(&rt->u.dst.__refcnt, 1);

	return rt;
}

static int fib6_ifdown(struct rt6_info *rt, void *arg)
{
	if (((void*)rt->rt6i_dev == arg || arg == NULL) &&
	    rt != &ip6_null_entry) {
		RT6_TRACE("deleted by ifdown %p\n", rt);
		return -1;
	}
	return 0;
}

void rt6_ifdown(struct net_device *dev)
{
T
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	fib6_clean_all(fib6_ifdown, 0, dev);
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}

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 &&
	    !dst_metric_locked(&rt->u.dst, RTAX_MTU) &&
1984 1985
	    (dst_mtu(&rt->u.dst) > arg->mtu ||
	     (dst_mtu(&rt->u.dst) < arg->mtu &&
L
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	      dst_mtu(&rt->u.dst) == idev->cnf.mtu6)))
		rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu;
	rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(arg->mtu);
	return 0;
}

void rt6_mtu_change(struct net_device *dev, unsigned mtu)
{
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	struct rt6_mtu_change_arg arg = {
		.dev = dev,
		.mtu = mtu,
	};
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T
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	fib6_clean_all(rt6_mtu_change_route, 0, &arg);
L
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}

2002
static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2003
	[RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2004
	[RTA_OIF]               = { .type = NLA_U32 },
2005
	[RTA_IIF]		= { .type = NLA_U32 },
2006 2007 2008 2009 2010 2011
	[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
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{
2013 2014 2015
	struct rtmsg *rtm;
	struct nlattr *tb[RTA_MAX+1];
	int err;
L
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2017 2018 2019
	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
	if (err < 0)
		goto errout;
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2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039
	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;

	cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
	cfg->fc_nlinfo.nlh = nlh;

	if (tb[RTA_GATEWAY]) {
		nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
		cfg->fc_flags |= RTF_GATEWAY;
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	}
2041 2042 2043 2044 2045 2046 2047 2048

	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);
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	}
2050 2051 2052 2053 2054 2055 2056 2057

	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);
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	}
2059 2060 2061 2062 2063 2064 2065 2066 2067 2068

	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]);
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	}
2070 2071 2072 2073 2074 2075 2076

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

	err = 0;
errout:
	return err;
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}

2079
static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
L
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2080
{
2081 2082
	struct fib6_config cfg;
	int err;
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2084 2085 2086 2087 2088
	err = rtm_to_fib6_config(skb, nlh, &cfg);
	if (err < 0)
		return err;

	return ip6_route_del(&cfg);
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}

2091
static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
L
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2092
{
2093 2094
	struct fib6_config cfg;
	int err;
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2096 2097 2098 2099 2100
	err = rtm_to_fib6_config(skb, nlh, &cfg);
	if (err < 0)
		return err;

	return ip6_route_add(&cfg);
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}

2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113
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 */
2114
	       + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2115 2116 2117
	       + nla_total_size(sizeof(struct rta_cacheinfo));
}

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2118
static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
2119 2120 2121
			 struct in6_addr *dst, struct in6_addr *src,
			 int iif, int type, u32 pid, u32 seq,
			 int prefix, unsigned int flags)
L
Linus Torvalds 已提交
2122 2123
{
	struct rtmsg *rtm;
2124
	struct nlmsghdr *nlh;
2125
	long expires;
2126
	u32 table;
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2127 2128 2129 2130 2131 2132 2133 2134

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

2135 2136
	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
	if (nlh == NULL)
2137
		return -EMSGSIZE;
2138 2139

	rtm = nlmsg_data(nlh);
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2140 2141 2142 2143
	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
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2144
	if (rt->rt6i_table)
2145
		table = rt->rt6i_table->tb6_id;
T
Thomas Graf 已提交
2146
	else
2147 2148
		table = RT6_TABLE_UNSPEC;
	rtm->rtm_table = table;
2149
	NLA_PUT_U32(skb, RTA_TABLE, table);
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2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169
	if (rt->rt6i_flags&RTF_REJECT)
		rtm->rtm_type = RTN_UNREACHABLE;
	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) {
2170
		NLA_PUT(skb, RTA_DST, 16, dst);
2171
		rtm->rtm_dst_len = 128;
L
Linus Torvalds 已提交
2172
	} else if (rtm->rtm_dst_len)
2173
		NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
L
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2174 2175
#ifdef CONFIG_IPV6_SUBTREES
	if (src) {
2176
		NLA_PUT(skb, RTA_SRC, 16, src);
2177
		rtm->rtm_src_len = 128;
L
Linus Torvalds 已提交
2178
	} else if (rtm->rtm_src_len)
2179
		NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
L
Linus Torvalds 已提交
2180 2181
#endif
	if (iif)
2182
		NLA_PUT_U32(skb, RTA_IIF, iif);
L
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2183 2184 2185
	else if (dst) {
		struct in6_addr saddr_buf;
		if (ipv6_get_saddr(&rt->u.dst, dst, &saddr_buf) == 0)
2186
			NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
L
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2187
	}
2188

L
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2189
	if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
2190 2191
		goto nla_put_failure;

L
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2192
	if (rt->u.dst.neighbour)
2193 2194
		NLA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key);

L
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2195
	if (rt->u.dst.dev)
2196 2197 2198
		NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);

	NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2199 2200 2201 2202 2203

	expires = rt->rt6i_expires ? rt->rt6i_expires - jiffies : 0;
	if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0,
			       expires, rt->u.dst.error) < 0)
		goto nla_put_failure;
2204 2205 2206 2207

	return nlmsg_end(skb, nlh);

nla_put_failure:
2208 2209
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
L
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2210 2211
}

2212
int rt6_dump_route(struct rt6_info *rt, void *p_arg)
L
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2213 2214 2215 2216
{
	struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
	int prefix;

2217 2218
	if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
		struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
L
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2219 2220 2221 2222 2223 2224
		prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
	} else
		prefix = 0;

	return rt6_fill_node(arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
		     NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2225
		     prefix, NLM_F_MULTI);
L
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2226 2227
}

2228
static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
L
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2229
{
2230 2231
	struct nlattr *tb[RTA_MAX+1];
	struct rt6_info *rt;
L
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2232
	struct sk_buff *skb;
2233
	struct rtmsg *rtm;
L
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2234
	struct flowi fl;
2235
	int err, iif = 0;
L
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2236

2237 2238 2239
	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
	if (err < 0)
		goto errout;
L
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2240

2241
	err = -EINVAL;
L
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2242 2243
	memset(&fl, 0, sizeof(fl));

2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262
	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
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2263 2264 2265 2266 2267 2268

	if (iif) {
		struct net_device *dev;
		dev = __dev_get_by_index(iif);
		if (!dev) {
			err = -ENODEV;
2269
			goto errout;
L
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2270 2271 2272
		}
	}

2273 2274 2275 2276 2277
	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
	if (skb == NULL) {
		err = -ENOBUFS;
		goto errout;
	}
L
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2278

2279 2280 2281
	/* Reserve room for dummy headers, this skb can pass
	   through good chunk of routing engine.
	 */
2282
	skb_reset_mac_header(skb);
2283
	skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
L
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2284

2285
	rt = (struct rt6_info*) ip6_route_output(NULL, &fl);
L
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2286 2287
	skb->dst = &rt->u.dst;

2288
	err = rt6_fill_node(skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
L
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2289
			    RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2290
			    nlh->nlmsg_seq, 0, 0);
L
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2291
	if (err < 0) {
2292 2293
		kfree_skb(skb);
		goto errout;
L
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2294 2295
	}

2296
	err = rtnl_unicast(skb, NETLINK_CB(in_skb).pid);
2297
errout:
L
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	return err;
}

2301
void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
L
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2302 2303
{
	struct sk_buff *skb;
2304 2305
	u32 pid = 0, seq = 0;
	struct nlmsghdr *nlh = NULL;
2306 2307
	int err = -ENOBUFS;

2308 2309 2310 2311 2312 2313 2314
	if (info) {
		pid = info->pid;
		nlh = info->nlh;
		if (nlh)
			seq = nlh->nlmsg_seq;
	}

2315
	skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2316 2317 2318 2319
	if (skb == NULL)
		goto errout;

	err = rt6_fill_node(skb, rt, NULL, NULL, 0, event, pid, seq, 0, 0);
2320 2321 2322 2323 2324 2325
	if (err < 0) {
		/* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(skb);
		goto errout;
	}
2326 2327 2328 2329
	err = rtnl_notify(skb, pid, RTNLGRP_IPV6_ROUTE, nlh, gfp_any());
errout:
	if (err < 0)
		rtnl_set_sk_err(RTNLGRP_IPV6_ROUTE, err);
L
Linus Torvalds 已提交
2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360
}

/*
 *	/proc
 */

#ifdef CONFIG_PROC_FS

#define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1)

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)
{
	struct rt6_proc_arg *arg = (struct rt6_proc_arg *) p_arg;

	if (arg->skip < arg->offset / RT6_INFO_LEN) {
		arg->skip++;
		return 0;
	}

	if (arg->len >= arg->length)
		return 0;

2361 2362 2363
	arg->len += sprintf(arg->buffer + arg->len,
			    NIP6_SEQFMT " %02x ",
			    NIP6(rt->rt6i_dst.addr),
L
Linus Torvalds 已提交
2364 2365 2366
			    rt->rt6i_dst.plen);

#ifdef CONFIG_IPV6_SUBTREES
2367 2368 2369
	arg->len += sprintf(arg->buffer + arg->len,
			    NIP6_SEQFMT " %02x ",
			    NIP6(rt->rt6i_src.addr),
L
Linus Torvalds 已提交
2370 2371
			    rt->rt6i_src.plen);
#else
2372 2373
	arg->len += sprintf(arg->buffer + arg->len,
			    "00000000000000000000000000000000 00 ");
L
Linus Torvalds 已提交
2374 2375 2376
#endif

	if (rt->rt6i_nexthop) {
2377 2378 2379
		arg->len += sprintf(arg->buffer + arg->len,
				    NIP6_SEQFMT,
				    NIP6(*((struct in6_addr *)rt->rt6i_nexthop->primary_key)));
L
Linus Torvalds 已提交
2380
	} else {
2381 2382
		arg->len += sprintf(arg->buffer + arg->len,
				    "00000000000000000000000000000000");
L
Linus Torvalds 已提交
2383 2384 2385 2386
	}
	arg->len += sprintf(arg->buffer + arg->len,
			    " %08x %08x %08x %08x %8s\n",
			    rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt),
2387
			    rt->u.dst.__use, rt->rt6i_flags,
L
Linus Torvalds 已提交
2388 2389 2390 2391 2392 2393
			    rt->rt6i_dev ? rt->rt6i_dev->name : "");
	return 0;
}

static int rt6_proc_info(char *buffer, char **start, off_t offset, int length)
{
T
Thomas Graf 已提交
2394 2395 2396 2397 2398
	struct rt6_proc_arg arg = {
		.buffer = buffer,
		.offset = offset,
		.length = length,
	};
L
Linus Torvalds 已提交
2399

T
Thomas Graf 已提交
2400
	fib6_clean_all(rt6_info_route, 0, &arg);
L
Linus Torvalds 已提交
2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432

	*start = buffer;
	if (offset)
		*start += offset % RT6_INFO_LEN;

	arg.len -= offset % RT6_INFO_LEN;

	if (arg.len > length)
		arg.len = length;
	if (arg.len < 0)
		arg.len = 0;

	return arg.len;
}

static int rt6_stats_seq_show(struct seq_file *seq, void *v)
{
	seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
		      rt6_stats.fib_nodes, rt6_stats.fib_route_nodes,
		      rt6_stats.fib_rt_alloc, rt6_stats.fib_rt_entries,
		      rt6_stats.fib_rt_cache,
		      atomic_read(&ip6_dst_ops.entries),
		      rt6_stats.fib_discarded_routes);

	return 0;
}

static int rt6_stats_seq_open(struct inode *inode, struct file *file)
{
	return single_open(file, rt6_stats_seq_show, NULL);
}

2433
static const struct file_operations rt6_stats_seq_fops = {
L
Linus Torvalds 已提交
2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458
	.owner	 = THIS_MODULE,
	.open	 = rt6_stats_seq_open,
	.read	 = seq_read,
	.llseek	 = seq_lseek,
	.release = single_release,
};
#endif	/* CONFIG_PROC_FS */

#ifdef CONFIG_SYSCTL

static int flush_delay;

static
int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write, struct file * filp,
			      void __user *buffer, size_t *lenp, loff_t *ppos)
{
	if (write) {
		proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
		fib6_run_gc(flush_delay <= 0 ? ~0UL : (unsigned long)flush_delay);
		return 0;
	} else
		return -EINVAL;
}

ctl_table ipv6_route_table[] = {
2459 2460
	{
		.ctl_name	=	NET_IPV6_ROUTE_FLUSH,
L
Linus Torvalds 已提交
2461
		.procname	=	"flush",
2462
		.data		=	&flush_delay,
L
Linus Torvalds 已提交
2463
		.maxlen		=	sizeof(int),
2464
		.mode		=	0200,
2465
		.proc_handler	=	&ipv6_sysctl_rtcache_flush
L
Linus Torvalds 已提交
2466 2467 2468 2469
	},
	{
		.ctl_name	=	NET_IPV6_ROUTE_GC_THRESH,
		.procname	=	"gc_thresh",
2470
		.data		=	&ip6_dst_ops.gc_thresh,
L
Linus Torvalds 已提交
2471 2472
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2473
		.proc_handler	=	&proc_dointvec,
L
Linus Torvalds 已提交
2474 2475 2476 2477
	},
	{
		.ctl_name	=	NET_IPV6_ROUTE_MAX_SIZE,
		.procname	=	"max_size",
2478
		.data		=	&ip6_rt_max_size,
L
Linus Torvalds 已提交
2479 2480
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2481
		.proc_handler	=	&proc_dointvec,
L
Linus Torvalds 已提交
2482 2483 2484 2485
	},
	{
		.ctl_name	=	NET_IPV6_ROUTE_GC_MIN_INTERVAL,
		.procname	=	"gc_min_interval",
2486
		.data		=	&ip6_rt_gc_min_interval,
L
Linus Torvalds 已提交
2487 2488
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2489
		.proc_handler	=	&proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2490 2491 2492 2493 2494
		.strategy	=	&sysctl_jiffies,
	},
	{
		.ctl_name	=	NET_IPV6_ROUTE_GC_TIMEOUT,
		.procname	=	"gc_timeout",
2495
		.data		=	&ip6_rt_gc_timeout,
L
Linus Torvalds 已提交
2496 2497
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2498
		.proc_handler	=	&proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2499 2500 2501 2502 2503
		.strategy	=	&sysctl_jiffies,
	},
	{
		.ctl_name	=	NET_IPV6_ROUTE_GC_INTERVAL,
		.procname	=	"gc_interval",
2504
		.data		=	&ip6_rt_gc_interval,
L
Linus Torvalds 已提交
2505 2506
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2507
		.proc_handler	=	&proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2508 2509 2510 2511 2512
		.strategy	=	&sysctl_jiffies,
	},
	{
		.ctl_name	=	NET_IPV6_ROUTE_GC_ELASTICITY,
		.procname	=	"gc_elasticity",
2513
		.data		=	&ip6_rt_gc_elasticity,
L
Linus Torvalds 已提交
2514 2515
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2516
		.proc_handler	=	&proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2517 2518 2519 2520 2521
		.strategy	=	&sysctl_jiffies,
	},
	{
		.ctl_name	=	NET_IPV6_ROUTE_MTU_EXPIRES,
		.procname	=	"mtu_expires",
2522
		.data		=	&ip6_rt_mtu_expires,
L
Linus Torvalds 已提交
2523 2524
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2525
		.proc_handler	=	&proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2526 2527 2528 2529 2530
		.strategy	=	&sysctl_jiffies,
	},
	{
		.ctl_name	=	NET_IPV6_ROUTE_MIN_ADVMSS,
		.procname	=	"min_adv_mss",
2531
		.data		=	&ip6_rt_min_advmss,
L
Linus Torvalds 已提交
2532 2533
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2534
		.proc_handler	=	&proc_dointvec_jiffies,
L
Linus Torvalds 已提交
2535 2536 2537 2538 2539
		.strategy	=	&sysctl_jiffies,
	},
	{
		.ctl_name	=	NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS,
		.procname	=	"gc_min_interval_ms",
2540
		.data		=	&ip6_rt_gc_min_interval,
L
Linus Torvalds 已提交
2541 2542
		.maxlen		=	sizeof(int),
		.mode		=	0644,
2543
		.proc_handler	=	&proc_dointvec_ms_jiffies,
L
Linus Torvalds 已提交
2544 2545 2546 2547 2548 2549 2550 2551 2552
		.strategy	=	&sysctl_ms_jiffies,
	},
	{ .ctl_name = 0 }
};

#endif

void __init ip6_route_init(void)
{
2553
#ifdef 	CONFIG_PROC_FS
L
Linus Torvalds 已提交
2554
	struct proc_dir_entry *p;
2555
#endif
A
Alexey Dobriyan 已提交
2556 2557
	ip6_dst_ops.kmem_cachep =
		kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
2558
				  SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
2559 2560
	ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops.kmem_cachep;

L
Linus Torvalds 已提交
2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571
	fib6_init();
#ifdef 	CONFIG_PROC_FS
	p = proc_net_create("ipv6_route", 0, rt6_proc_info);
	if (p)
		p->owner = THIS_MODULE;

	proc_net_fops_create("rt6_stats", S_IRUGO, &rt6_stats_seq_fops);
#endif
#ifdef CONFIG_XFRM
	xfrm6_init();
#endif
T
Thomas Graf 已提交
2572 2573 2574
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
	fib6_rules_init();
#endif
2575 2576 2577 2578

	__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);
L
Linus Torvalds 已提交
2579 2580 2581 2582
}

void ip6_route_cleanup(void)
{
T
Thomas Graf 已提交
2583 2584 2585
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
	fib6_rules_cleanup();
#endif
L
Linus Torvalds 已提交
2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596
#ifdef CONFIG_PROC_FS
	proc_net_remove("ipv6_route");
	proc_net_remove("rt6_stats");
#endif
#ifdef CONFIG_XFRM
	xfrm6_fini();
#endif
	rt6_ifdown(NULL);
	fib6_gc_cleanup();
	kmem_cache_destroy(ip6_dst_ops.kmem_cachep);
}