client6_addr.c

DHCPv6协议在Linux操作系统下的一个客户端实现。

/*	$Id: client6_addr.c,v 1.22 2003/07/02 02:21:25 shirleyma Exp $	*/

/*
 * Copyright (C) International Business Machines  Corp., 2003
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/* Author: Shirley Ma, [e-mail] */

#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/ioctl.h>

#include <linux/ipv6.h>

#include <net/if.h>
#include <time.h>
#include <errno.h>
#include <syslog.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <net/if_arp.h>

#include "queue.h"
#include "dhcp6.h"
#include "config.h"
#include "common.h"
#include "timer.h"
#include "lease.h"

static int dhcp6_update_lease __P((struct dhcp6_addr *, struct dhcp6_lease *));
static int dhcp6_add_lease __P((struct dhcp6_addr *));
struct dhcp6_lease *dhcp6_find_lease __P((struct dhcp6_iaidaddr *, 
			struct dhcp6_addr *));
int dhcp6_get_prefixlen __P((struct in6_addr *, struct dhcp6_if *));
int client6_ifaddrconf __P((ifaddrconf_cmd_t, struct dhcp6_addr *));
u_int32_t get_min_preferlifetime __P((struct dhcp6_iaidaddr *));
u_int32_t get_max_validlifetime __P((struct dhcp6_iaidaddr *));
struct dhcp6_timer *dhcp6_iaidaddr_timo __P((void *));
struct dhcp6_timer *dhcp6_lease_timo __P((void *));

extern struct dhcp6_iaidaddr client6_iaidaddr;
extern struct dhcp6_timer *client6_timo __P((void *));
extern void client6_send __P((struct dhcp6_event *));
extern void free_servers __P((struct dhcp6_if *));
extern ssize_t gethwid __P((char *, int, const char *, u_int16_t *));

extern int nlsock;
extern FILE *client6_lease_file;
extern struct dhcp6_iaidaddr client6_iaidaddr;
extern struct dhcp6_list request_list;

void
dhcp6_init_iaidaddr(void)
{
	memset(&client6_iaidaddr, 0, sizeof(client6_iaidaddr));
	TAILQ_INIT(&client6_iaidaddr.lease_list);
}

int
dhcp6_add_iaidaddr(struct dhcp6_optinfo *optinfo)
{
	struct dhcp6_listval *lv, *lv_next = NULL;
	struct timeval timo;
	struct dhcp6_lease *cl_lease;
	double d;
	/* ignore IA with T1 > T2 */
	if (client6_iaidaddr.client6_info.iaidinfo.renewtime >
	    client6_iaidaddr.client6_info.iaidinfo.rebindtime) {
		dprintf(LOG_INFO, " T1 time is greater than T2 time");
		return (0);
	}
	memcpy(&client6_iaidaddr.client6_info.iaidinfo, &optinfo->iaidinfo, 
			sizeof(client6_iaidaddr.client6_info.iaidinfo));
	client6_iaidaddr.client6_info.type = optinfo->type;
	duidcpy(&client6_iaidaddr.client6_info.clientid, &optinfo->clientID);
	if (duidcpy(&client6_iaidaddr.client6_info.serverid, &optinfo->serverID)) {
		dprintf(LOG_ERR, "%s" "failed to copy server ID %s", 
			FNAME, duidstr(&optinfo->serverID));
		return (-1);
	}
	/* add new address */
	for (lv = TAILQ_FIRST(&optinfo->addr_list); lv; lv = lv_next) {
		lv_next = TAILQ_NEXT(lv, link);
		if (lv->val_dhcp6addr.type != IAPD) {	
			lv->val_dhcp6addr.plen = 
				dhcp6_get_prefixlen(&lv->val_dhcp6addr.addr, dhcp6_if);
			if (lv->val_dhcp6addr.plen == PREFIX_LEN_NOTINRA) {
				dprintf(LOG_WARNING, 
					"assigned address %s prefix len is not in any RAs"
					" prefix length using 64 bit instead",
					in6addr2str(&lv->val_dhcp6addr.addr, 0));
			}
		}
		if ((cl_lease = dhcp6_find_lease(&client6_iaidaddr, 
						&lv->val_dhcp6addr)) != NULL) {
			dhcp6_update_lease(&lv->val_dhcp6addr, cl_lease);
			continue;
		}
		if (dhcp6_add_lease(&lv->val_dhcp6addr)) {
			dprintf(LOG_ERR, "%s" "failed to add a new addr lease %s", 
				FNAME, in6addr2str(&lv->val_dhcp6addr.addr, 0));
			continue;
		}
	}
	if (TAILQ_EMPTY(&client6_iaidaddr.lease_list))
		return 0;
	/* set up renew T1, rebind T2 timer renew/rebind based on iaid */
	/* Should we process IA_TA, IA_NA differently */
	if (client6_iaidaddr.client6_info.iaidinfo.renewtime == 0 ||
	    client6_iaidaddr.client6_info.iaidinfo.renewtime >
	    client6_iaidaddr.client6_info.iaidinfo.rebindtime) {
		u_int32_t min_plifetime;
		min_plifetime = get_min_preferlifetime(&client6_iaidaddr);
		if (min_plifetime == DHCP6_DURATITION_INFINITE)
			client6_iaidaddr.client6_info.iaidinfo.renewtime = min_plifetime;
		else
			client6_iaidaddr.client6_info.iaidinfo.renewtime = min_plifetime / 2;
	}
	if (client6_iaidaddr.client6_info.iaidinfo.rebindtime == 0 ||
		 client6_iaidaddr.client6_info.iaidinfo.renewtime >
		 client6_iaidaddr.client6_info.iaidinfo.rebindtime) {
		client6_iaidaddr.client6_info.iaidinfo.rebindtime = 
			get_min_preferlifetime(&client6_iaidaddr) * 4 / 5;
	}
	dprintf(LOG_INFO, "renew time %d, rebind time %d", 
		client6_iaidaddr.client6_info.iaidinfo.renewtime,
		client6_iaidaddr.client6_info.iaidinfo.rebindtime);
	if (client6_iaidaddr.client6_info.iaidinfo.renewtime == 0)
		return (0);
	if (client6_iaidaddr.client6_info.iaidinfo.renewtime == DHCP6_DURATITION_INFINITE) {
		client6_iaidaddr.client6_info.iaidinfo.rebindtime == DHCP6_DURATITION_INFINITE;
		return (0);
	}
	/* set up start date, and renew timer */
	if ((client6_iaidaddr.timer = 
	    dhcp6_add_timer(dhcp6_iaidaddr_timo, &client6_iaidaddr)) == NULL) {
		 dprintf(LOG_ERR, "%s" "failed to add a timer for iaid %u",
			FNAME, client6_iaidaddr.client6_info.iaidinfo.iaid);
		 return (-1);
	}
	time(&client6_iaidaddr.start_date);
	client6_iaidaddr.state = ACTIVE;
	d = client6_iaidaddr.client6_info.iaidinfo.renewtime;
	timo.tv_sec = (long)d;
	timo.tv_usec = 0;
	dhcp6_set_timer(&timo, client6_iaidaddr.timer);
	return (0);
}

int
dhcp6_add_lease(addr)
	struct dhcp6_addr *addr;
{
	struct dhcp6_lease *sp;
	struct timeval timo;
	double d;

	dprintf(LOG_DEBUG, "%s" "try to add address %s", FNAME,
		in6addr2str(&addr->addr, 0));
	
	/* ignore meaningless address */
	if (addr->status_code != DH6OPT_STCODE_SUCCESS &&
			addr->status_code != DH6OPT_STCODE_UNDEFINE) {
		dprintf(LOG_ERR, "%s" "not successful status code for %s is %s", FNAME,
			in6addr2str(&addr->addr, 0), dhcp6_stcodestr(addr->status_code));
		return (0);
	}
	if (addr->validlifetime == 0 || addr->preferlifetime == 0 ||
	    addr->preferlifetime > addr->validlifetime) {
		dprintf(LOG_ERR, "%s" "invalid address life time for %s",
			FNAME, in6addr2str(&addr->addr, 0));
		return (0);
	}
	if ((sp = dhcp6_find_lease(&client6_iaidaddr, addr)) != NULL) {
		dprintf(LOG_ERR, "%s" "duplicated address: %s",
		    FNAME, in6addr2str(&addr->addr, 0));
		return (-1);
	}
	if ((sp = (struct dhcp6_lease *)malloc(sizeof(*sp))) == NULL) {
		dprintf(LOG_ERR, "%s" "failed to allocate memory"
			" for a addr", FNAME);
		return (-1);
	}
	memset(sp, 0, sizeof(*sp));
	memcpy(&sp->lease_addr, addr, sizeof(sp->lease_addr));
	sp->iaidaddr = &client6_iaidaddr;
	time(&sp->start_date);
	sp->state = ACTIVE;
	if (write_lease(sp, client6_lease_file) != 0) {
		dprintf(LOG_ERR, "%s" "failed to write a new lease address %s to lease file", 
			FNAME, in6addr2str(&sp->lease_addr.addr, 0));
		if (sp->timer)
			dhcp6_remove_timer(sp->timer);
		free(sp);
		return (-1);
	}
	if (sp->lease_addr.type == IAPD) {
		dprintf(LOG_INFO, "request prefix is %s/%d", 
			in6addr2str(&sp->lease_addr.addr, 0), sp->lease_addr.plen);
	} else if (client6_ifaddrconf(IFADDRCONF_ADD, addr) != 0) {
		dprintf(LOG_ERR, "%s" "adding address failed: %s",
		    FNAME, in6addr2str(&addr->addr, 0));
		if (sp->timer)
			dhcp6_remove_timer(sp->timer);
		free(sp);
		return (-1);
	}
	TAILQ_INSERT_TAIL(&client6_iaidaddr.lease_list, sp, link);
	/* for infinite lifetime don't do any timer */
	if (sp->lease_addr.validlifetime == DHCP6_DURATITION_INFINITE || 
	    sp->lease_addr.preferlifetime == DHCP6_DURATITION_INFINITE) {
		dprintf(LOG_INFO, "%s" "infinity address life time for %s",
			FNAME, in6addr2str(&addr->addr, 0));
		return (0);
	}
	/* set up expired timer for lease*/
	if ((sp->timer = dhcp6_add_timer(dhcp6_lease_timo, sp)) == NULL) {
		dprintf(LOG_ERR, "%s" "failed to add a timer for lease %s",
			FNAME, in6addr2str(&addr->addr, 0));
		free(sp);
		return (-1);
	}
	d = sp->lease_addr.preferlifetime;
	timo.tv_sec = (long)d;
	timo.tv_usec = 0;
	dhcp6_set_timer(&timo, sp->timer);
	return 0;
}

int
dhcp6_remove_iaidaddr(struct dhcp6_iaidaddr *iaidaddr)
{
	struct dhcp6_lease *lv, *lv_next;
	for (lv = TAILQ_FIRST(&iaidaddr->lease_list); lv; lv = lv_next) { 
		lv_next = TAILQ_NEXT(lv, link);
		(void)dhcp6_remove_lease(lv);
	}
	/*
	if (iaidaddr->client6_info.serverid.duid_id != NULL)
		duidfree(&iaidaddr->client6_info.serverid);
	 */
	if (iaidaddr->timer)
		dhcp6_remove_timer(iaidaddr->timer);
	TAILQ_INIT(&iaidaddr->lease_list);
	return 0;
}

int
dhcp6_remove_lease(struct dhcp6_lease *sp)
{
	dprintf(LOG_DEBUG, "%s" "removing address %s", FNAME,
		in6addr2str(&sp->lease_addr.addr, 0));
	sp->state = INVALID;
	if (write_lease(sp, client6_lease_file) != 0) {
		dprintf(LOG_INFO, "%s" 
			"failed to write removed lease address %s to lease file", 
			FNAME, in6addr2str(&sp->lease_addr.addr, 0));
		return (-1);
	}
	/* XXX: ToDo: prefix delegation for client */
	if (sp->lease_addr.type == IAPD) {
		dprintf(LOG_INFO, "request prefix is %s/%d", 
			in6addr2str(&sp->lease_addr.addr, 0), sp->lease_addr.plen);
		/* XXX: remove from the update prefix list */

	} else if (client6_ifaddrconf(IFADDRCONF_REMOVE, &sp->lease_addr) != 0) {
			dprintf(LOG_INFO, "%s" "removing address %s failed",
		    		FNAME, in6addr2str(&sp->lease_addr.addr, 0));
	}
	/* remove expired timer for this lease. */
	if (sp->timer)
		dhcp6_remove_timer(sp->timer);
	TAILQ_REMOVE(&client6_iaidaddr.lease_list, sp, link);
	free(sp);
	/* can't remove expired iaidaddr even there is no lease in this iaidaddr
	 * since the rebind->solicit timer uses this iaidaddr
	 * if(TAILQ_EMPTY(&client6_iaidaddr.lease_list))
	 *	dhcp6_remove_iaidaddr();
	 */
	return 0;
}

int
dhcp6_update_iaidaddr(struct dhcp6_optinfo *optinfo, int flag)
{
	struct dhcp6_listval *lv, *lv_next = NULL;
	struct dhcp6_lease *cl, *cl_next;
	struct timeval timo;
	double d;
	if (client6_iaidaddr.client6_info.iaidinfo.renewtime >
	    client6_iaidaddr.client6_info.iaidinfo.rebindtime) {
		dprintf(LOG_INFO, " T1 time is greater than T2 time");
		return (0);
	}
	if (flag == ADDR_REMOVE) {
		for (lv = TAILQ_FIRST(&optinfo->addr_list); lv; lv = lv_next) {
			lv_next = TAILQ_NEXT(lv, link);
			cl = dhcp6_find_lease(&client6_iaidaddr, &lv->val_dhcp6addr);
			if (cl) {
				/* remove leases */
				dhcp6_remove_lease(cl);
			}
		}
		return 0;
	}
	/* flag == ADDR_UPDATE */
	for (lv = TAILQ_FIRST(&optinfo->addr_list); lv; lv = lv_next) {
		lv_next = TAILQ_NEXT(lv, link);
		if (lv->val_dhcp6addr.type != IAPD) {	
			lv->val_dhcp6addr.plen = 
				dhcp6_get_prefixlen(&lv->val_dhcp6addr.addr, dhcp6_if);
			if (lv->val_dhcp6addr.plen == PREFIX_LEN_NOTINRA) {
				dprintf(LOG_WARNING, "assigned address %s is not in any RAs"
					" prefix length using 64 bit instead",
					in6addr2str(&lv->val_dhcp6addr.addr, 0)); 
			}
		}
		if ((cl = dhcp6_find_lease(&client6_iaidaddr, &lv->val_dhcp6addr)) != NULL) {
		/* update leases */
			dhcp6_update_lease(&lv->val_dhcp6addr, cl);
			continue;
		}
		/* need to add the new leases */	
		if (dhcp6_add_lease(&lv->val_dhcp6addr)) {
			dprintf(LOG_INFO, "%s" "failed to add a new addr lease %s",
				FNAME, in6addr2str(&lv->val_dhcp6addr.addr, 0));
			continue;
		}
		continue;
	}
	/* remove leases that not on the updated list */
	for (cl = TAILQ_FIRST(&client6_iaidaddr.lease_list); cl; cl = cl_next) { 
			cl_next = TAILQ_NEXT(cl, link);
		lv = dhcp6_find_listval(&optinfo->addr_list, &cl->lease_addr, 
			DHCP6_LISTVAL_DHCP6ADDR);
		/* remove leases that not on the updated list */
		if (lv == NULL)
			dhcp6_remove_lease(cl);
	}	
	/* update server id */