mn_agentadv.h

mobile ip 在linux下的一种实现

/* $Id: mn_agentadv.h,v 1.32 2001/09/23 16:07:14 jm Exp $
 * Header files for Mobile Node agentadv module
 *
 * Dynamic hierarchial IP tunnel
 * Copyright (C) 1998-2001, Dynamics group
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation. See README and COPYING for
 * more details.
 */

#ifndef MN_AGENTADV_H
#define MN_AGENTADV_H

#include "agentadv.h"
#include "list.h"
#include "sys/time.h"
#include "hashtable.h"

/* keep agentadv data for x seconds after the expiration */
#define ADV_EXTRA_TIME 10
/* check agentadv data for expired entries every x seconds */
#define ADV_CLEANUP_FREQ 10


/* get_fa() return values: */
#define FA_GET_NO 0
#define FA_GET_CHANGED 1
#define FA_GET_SAME 2

#define MAX_FA_NAI_LEN (sizeof(struct fa_nai_ext) + 255)

enum {
	MN_ADV_TYPE_UNKNOWN = 0,
	MN_ADV_TYPE_FA /* FA (and possibly unknown HA) */,
	MN_ADV_TYPE_HA /* unknown HA */,
	MN_ADV_TYPE_OWN_HA /* our own HA (and possibly FA) */
};

/* key for the agentadv_data hashtable */
struct agentadv_key {
	struct in_addr addr;
	int ifindex;
};

struct agentadv_data {
	struct node node; /* entry hashed into the hashtable */

	struct in_addr addr; /* address of the FA sending this advertisement */
	int ifindex; /* interface that received the last agentadv */
	char ifname[IFNAMSIZ];
	struct timeval last; /* time when this advertisement was received */
	struct timeval expire; /* expiration time for this entry
				* (last + radv->lifetime + 1); i.e. this
				* _may_ be removed after this timestamp */

	char buf[MAX_ADV_MSG]; /* the last received agent advertisement */
	struct adv_extensions adv;

	int adv_type; /* MN_ADV_TYPE_* */
	int arpentry; /* 1 = own ARP entry used */
	int in_use;   /* 1 = currently registered to this FA or trying to
		       * register to this FA (i.e. do not expire the entry) */
	int priority; /* This is modified by FA_GET handlers */
	int priority_degraded; /* priority*(100-degrade) / 100 */
	int prio_degrade_percent; /* degrade priority this much percents */
	struct monitor_address *mon; /* monitor data */
	int routeentry; /* 1 = own host route entry used */
	unsigned long int counter; /* the number of received advs */
	long last_heard_seqn; /* sequence number of last heard advertisement */
	int reg_failed; /* 1 = reg. failed to this FA */
	int reg_retry_time; /* number of seconds to wait until the next
			     * registration request is sent */
};

struct interface_data;

int handle_icmp(struct interface_data *iface);
struct agentadv_data *get_ok_fa(void);
int clean_agentadv(struct node *node, void *data);
int get_fa(struct agentadv_data *adv);
struct agentadv_data *adv_fetch(struct hashtable *adv_hash, 
				struct in_addr *addr, int ifindex);
#endif