linux/include/net/ip6_route.h
Duan Jiong be7a010d6f ipv6: update Destination Cache entries when gateway turn into host
RFC 4861 states in 7.2.5:

	The IsRouter flag in the cache entry MUST be set based on the
         Router flag in the received advertisement.  In those cases
         where the IsRouter flag changes from TRUE to FALSE as a result
         of this update, the node MUST remove that router from the
         Default Router List and update the Destination Cache entries
         for all destinations using that neighbor as a router as
         specified in Section 7.3.3.  This is needed to detect when a
         node that is used as a router stops forwarding packets due to
         being configured as a host.

Currently, when dealing with NA Message which IsRouter flag changes from
TRUE to FALSE, the kernel only removes router from the Default Router List,
and don't update the Destination Cache entries.

Now in order to update those Destination Cache entries, i introduce
function rt6_clean_tohost().

Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-15 23:26:27 -04:00

201 lines
5.6 KiB
C

#ifndef _NET_IP6_ROUTE_H
#define _NET_IP6_ROUTE_H
struct route_info {
__u8 type;
__u8 length;
__u8 prefix_len;
#if defined(__BIG_ENDIAN_BITFIELD)
__u8 reserved_h:3,
route_pref:2,
reserved_l:3;
#elif defined(__LITTLE_ENDIAN_BITFIELD)
__u8 reserved_l:3,
route_pref:2,
reserved_h:3;
#endif
__be32 lifetime;
__u8 prefix[0]; /* 0,8 or 16 */
};
#include <net/flow.h>
#include <net/ip6_fib.h>
#include <net/sock.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/route.h>
#define RT6_LOOKUP_F_IFACE 0x00000001
#define RT6_LOOKUP_F_REACHABLE 0x00000002
#define RT6_LOOKUP_F_HAS_SADDR 0x00000004
#define RT6_LOOKUP_F_SRCPREF_TMP 0x00000008
#define RT6_LOOKUP_F_SRCPREF_PUBLIC 0x00000010
#define RT6_LOOKUP_F_SRCPREF_COA 0x00000020
/* We do not (yet ?) support IPv6 jumbograms (RFC 2675)
* Unlike IPv4, hdr->seg_len doesn't include the IPv6 header
*/
#define IP6_MAX_MTU (0xFFFF + sizeof(struct ipv6hdr))
/*
* rt6_srcprefs2flags() and rt6_flags2srcprefs() translate
* between IPV6_ADDR_PREFERENCES socket option values
* IPV6_PREFER_SRC_TMP = 0x1
* IPV6_PREFER_SRC_PUBLIC = 0x2
* IPV6_PREFER_SRC_COA = 0x4
* and above RT6_LOOKUP_F_SRCPREF_xxx flags.
*/
static inline int rt6_srcprefs2flags(unsigned int srcprefs)
{
/* No need to bitmask because srcprefs have only 3 bits. */
return srcprefs << 3;
}
static inline unsigned int rt6_flags2srcprefs(int flags)
{
return (flags >> 3) & 7;
}
static inline bool rt6_need_strict(const struct in6_addr *daddr)
{
return ipv6_addr_type(daddr) &
(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
}
void ip6_route_input(struct sk_buff *skb);
struct dst_entry *ip6_route_output(struct net *net, const struct sock *sk,
struct flowi6 *fl6);
struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
int flags);
int ip6_route_init(void);
void ip6_route_cleanup(void);
int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg);
int ip6_route_add(struct fib6_config *cfg);
int ip6_ins_rt(struct rt6_info *);
int ip6_del_rt(struct rt6_info *);
int ip6_route_get_saddr(struct net *net, struct rt6_info *rt,
const struct in6_addr *daddr, unsigned int prefs,
struct in6_addr *saddr);
struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
const struct in6_addr *saddr, int oif, int flags);
struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);
int icmp6_dst_gc(void);
void fib6_force_start_gc(struct net *net);
struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
const struct in6_addr *addr, bool anycast);
/*
* support functions for ND
*
*/
struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr,
struct net_device *dev);
struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
struct net_device *dev, unsigned int pref);
void rt6_purge_dflt_routers(struct net *net);
int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
const struct in6_addr *gwaddr);
void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
u32 mark);
void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark);
void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
u32 mark);
void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);
struct netlink_callback;
struct rt6_rtnl_dump_arg {
struct sk_buff *skb;
struct netlink_callback *cb;
struct net *net;
};
int rt6_dump_route(struct rt6_info *rt, void *p_arg);
void rt6_ifdown(struct net *net, struct net_device *dev);
void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
/*
* Store a destination cache entry in a socket
*/
static inline void __ip6_dst_store(struct sock *sk, struct dst_entry *dst,
const struct in6_addr *daddr,
const struct in6_addr *saddr)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct rt6_info *rt = (struct rt6_info *) dst;
sk_setup_caps(sk, dst);
np->daddr_cache = daddr;
#ifdef CONFIG_IPV6_SUBTREES
np->saddr_cache = saddr;
#endif
np->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
}
static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
struct in6_addr *daddr, struct in6_addr *saddr)
{
spin_lock(&sk->sk_dst_lock);
__ip6_dst_store(sk, dst, daddr, saddr);
spin_unlock(&sk->sk_dst_lock);
}
static inline bool ipv6_unicast_destination(const struct sk_buff *skb)
{
struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
return rt->rt6i_flags & RTF_LOCAL;
}
static inline bool ipv6_anycast_destination(const struct sk_buff *skb)
{
struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
return rt->rt6i_flags & RTF_ANYCAST;
}
int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
{
struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ?
skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
}
static inline bool ip6_sk_accept_pmtu(const struct sock *sk)
{
return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE &&
inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT;
}
static inline bool ip6_sk_local_df(const struct sock *sk)
{
return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO ||
inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT;
}
static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt)
{
return &rt->rt6i_gateway;
}
#endif