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linux/include/net/ndisc.h
David S. Miller 14deae4156 ipv6: Fix sporadic sendmsg -EINVAL when sending to multicast groups.
Thanks to excellent diagnosis by Eduard Guzovsky.

The core problem is that on a network with lots of active
multicast traffic, the neighbour cache can fill up.  If
we try to allocate a new route and thus neighbour cache
entry, the bog-standard GC attempt the neighbour layer does
in ineffective because route entries hold a reference
to the existing neighbour entries and GC can only liberate
entries with no references.

IPV4 already has a way to handle this, by doing a route cache
GC in such situations (when neigh attach returns -ENOBUFS).

So simply mimick this on the ipv6 side.

Tested-by: Eduard Guzovsky <eguzovsky@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-04 16:04:39 -08:00

168 lines
3.8 KiB
C

#ifndef _NDISC_H
#define _NDISC_H
/*
* ICMP codes for neighbour discovery messages
*/
#define NDISC_ROUTER_SOLICITATION 133
#define NDISC_ROUTER_ADVERTISEMENT 134
#define NDISC_NEIGHBOUR_SOLICITATION 135
#define NDISC_NEIGHBOUR_ADVERTISEMENT 136
#define NDISC_REDIRECT 137
/*
* Router type: cross-layer information from link-layer to
* IPv6 layer reported by certain link types (e.g., RFC4214).
*/
#define NDISC_NODETYPE_UNSPEC 0 /* unspecified (default) */
#define NDISC_NODETYPE_HOST 1 /* host or unauthorized router */
#define NDISC_NODETYPE_NODEFAULT 2 /* non-default router */
#define NDISC_NODETYPE_DEFAULT 3 /* default router */
/*
* ndisc options
*/
enum {
__ND_OPT_PREFIX_INFO_END = 0,
ND_OPT_SOURCE_LL_ADDR = 1, /* RFC2461 */
ND_OPT_TARGET_LL_ADDR = 2, /* RFC2461 */
ND_OPT_PREFIX_INFO = 3, /* RFC2461 */
ND_OPT_REDIRECT_HDR = 4, /* RFC2461 */
ND_OPT_MTU = 5, /* RFC2461 */
__ND_OPT_ARRAY_MAX,
ND_OPT_ROUTE_INFO = 24, /* RFC4191 */
ND_OPT_RDNSS = 25, /* RFC5006 */
__ND_OPT_MAX
};
#define MAX_RTR_SOLICITATION_DELAY HZ
#define ND_REACHABLE_TIME (30*HZ)
#define ND_RETRANS_TIMER HZ
#define ND_MIN_RANDOM_FACTOR (1/2)
#define ND_MAX_RANDOM_FACTOR (3/2)
#ifdef __KERNEL__
#include <linux/compiler.h>
#include <linux/icmpv6.h>
#include <linux/in6.h>
#include <linux/types.h>
#include <net/neighbour.h>
struct ctl_table;
struct file;
struct inet6_dev;
struct net_device;
struct net_proto_family;
struct sk_buff;
extern struct neigh_table nd_tbl;
struct nd_msg {
struct icmp6hdr icmph;
struct in6_addr target;
__u8 opt[0];
};
struct rs_msg {
struct icmp6hdr icmph;
__u8 opt[0];
};
struct ra_msg {
struct icmp6hdr icmph;
__be32 reachable_time;
__be32 retrans_timer;
};
struct nd_opt_hdr {
__u8 nd_opt_type;
__u8 nd_opt_len;
} __attribute__((__packed__));
extern int ndisc_init(void);
extern void ndisc_cleanup(void);
extern int ndisc_rcv(struct sk_buff *skb);
extern void ndisc_send_ns(struct net_device *dev,
struct neighbour *neigh,
const struct in6_addr *solicit,
const struct in6_addr *daddr,
const struct in6_addr *saddr);
extern void ndisc_send_rs(struct net_device *dev,
const struct in6_addr *saddr,
const struct in6_addr *daddr);
extern void ndisc_send_redirect(struct sk_buff *skb,
struct neighbour *neigh,
const struct in6_addr *target);
extern int ndisc_mc_map(struct in6_addr *addr, char *buf, struct net_device *dev, int dir);
extern struct sk_buff *ndisc_build_skb(struct net_device *dev,
const struct in6_addr *daddr,
const struct in6_addr *saddr,
struct icmp6hdr *icmp6h,
const struct in6_addr *target,
int llinfo);
extern void ndisc_send_skb(struct sk_buff *skb,
struct net_device *dev,
struct neighbour *neigh,
const struct in6_addr *daddr,
const struct in6_addr *saddr,
struct icmp6hdr *icmp6h);
/*
* IGMP
*/
extern int igmp6_init(void);
extern void igmp6_cleanup(void);
extern int igmp6_event_query(struct sk_buff *skb);
extern int igmp6_event_report(struct sk_buff *skb);
#ifdef CONFIG_SYSCTL
extern int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl,
int write,
struct file * filp,
void __user *buffer,
size_t *lenp,
loff_t *ppos);
int ndisc_ifinfo_sysctl_strategy(ctl_table *ctl,
void __user *oldval, size_t __user *oldlenp,
void __user *newval, size_t newlen);
#endif
extern void inet6_ifinfo_notify(int event,
struct inet6_dev *idev);
static inline struct neighbour * ndisc_get_neigh(struct net_device *dev, const struct in6_addr *addr)
{
if (dev)
return __neigh_lookup_errno(&nd_tbl, addr, dev);
return ERR_PTR(-ENODEV);
}
#endif /* __KERNEL__ */
#endif