[deliverable/linux.git] / net / ipv6 / addrconf.c

/*
 *	IPv6 Address [auto]configuration
 *	Linux INET6 implementation
 *
 *	Authors:
 *	Pedro Roque		<roque@di.fc.ul.pt>	
 *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
 *
 *	$Id: addrconf.c,v 1.69 2001/10/31 21:55:54 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:
 *
 *	Janos Farkas			:	delete timer on ifdown
 *	<chexum@bankinf.banki.hu>
 *	Andi Kleen			:	kill double kfree on module
 *						unload.
 *	Maciej W. Rozycki		:	FDDI support
 *	sekiya@USAGI			:	Don't send too many RS
 *						packets.
 *	yoshfuji@USAGI			:       Fixed interval between DAD
 *						packets.
 *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
 *						address validation timer.
 *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
 *						support.
 *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
 *						address on a same interface.
 *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
 *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
 *						seq_file.
 */

#include <linux/config.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/sched.h>
#include <linux/net.h>
#include <linux/in6.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/if_arcnet.h>
#include <linux/if_infiniband.h>
#include <linux/route.h>
#include <linux/inetdevice.h>
#include <linux/init.h>
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
#endif
#include <linux/delay.h>
#include <linux/notifier.h>
#include <linux/string.h>

#include <net/sock.h>
#include <net/snmp.h>

#include <net/ipv6.h>
#include <net/protocol.h>
#include <net/ndisc.h>
#include <net/ip6_route.h>
#include <net/addrconf.h>
#include <net/tcp.h>
#include <net/ip.h>
#include <linux/if_tunnel.h>
#include <linux/rtnetlink.h>

#ifdef CONFIG_IPV6_PRIVACY
#include <linux/random.h>
#include <linux/crypto.h>
#include <asm/scatterlist.h>
#endif

#include <asm/uaccess.h>

#include <linux/proc_fs.h>
#include <linux/seq_file.h>

/* Set to 3 to get tracing... */
#define ACONF_DEBUG 2

#if ACONF_DEBUG >= 3
#define ADBG(x) printk x
#else
#define ADBG(x)
#endif

#define	INFINITY_LIFE_TIME	0xFFFFFFFF
#define TIME_DELTA(a,b) ((unsigned long)((long)(a) - (long)(b)))

#ifdef CONFIG_SYSCTL
static void addrconf_sysctl_register(struct inet6_dev *idev, struct ipv6_devconf *p);
static void addrconf_sysctl_unregister(struct ipv6_devconf *p);
#endif

#ifdef CONFIG_IPV6_PRIVACY
static int __ipv6_regen_rndid(struct inet6_dev *idev);
static int __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr); 
static void ipv6_regen_rndid(unsigned long data);

static int desync_factor = MAX_DESYNC_FACTOR * HZ;
static struct crypto_tfm *md5_tfm;
static DEFINE_SPINLOCK(md5_tfm_lock);
#endif

static int ipv6_count_addresses(struct inet6_dev *idev);

/*
 *	Configured unicast address hash table
 */
static struct inet6_ifaddr		*inet6_addr_lst[IN6_ADDR_HSIZE];
static DEFINE_RWLOCK(addrconf_hash_lock);

/* Protects inet6 devices */
DEFINE_RWLOCK(addrconf_lock);

static void addrconf_verify(unsigned long);

static DEFINE_TIMER(addr_chk_timer, addrconf_verify, 0, 0);
static DEFINE_SPINLOCK(addrconf_verify_lock);

static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);

static int addrconf_ifdown(struct net_device *dev, int how);

static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags);
static void addrconf_dad_timer(unsigned long data);
static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
static void addrconf_rs_timer(unsigned long data);
static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);

static void inet6_prefix_notify(int event, struct inet6_dev *idev, 
				struct prefix_info *pinfo);
static int ipv6_chk_same_addr(const struct in6_addr *addr, struct net_device *dev);

static struct notifier_block *inet6addr_chain;

struct ipv6_devconf ipv6_devconf = {
	.forwarding		= 0,
	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
	.mtu6			= IPV6_MIN_MTU,
	.accept_ra		= 1,
	.accept_redirects	= 1,
	.autoconf		= 1,
	.force_mld_version	= 0,
	.dad_transmits		= 1,
	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
#ifdef CONFIG_IPV6_PRIVACY
	.use_tempaddr 		= 0,
	.temp_valid_lft		= TEMP_VALID_LIFETIME,
	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
	.regen_max_retry	= REGEN_MAX_RETRY,
	.max_desync_factor	= MAX_DESYNC_FACTOR,
#endif
	.max_addresses		= IPV6_MAX_ADDRESSES,
};

static struct ipv6_devconf ipv6_devconf_dflt = {
	.forwarding		= 0,
	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
	.mtu6			= IPV6_MIN_MTU,
	.accept_ra		= 1,
	.accept_redirects	= 1,
	.autoconf		= 1,
	.dad_transmits		= 1,
	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
#ifdef CONFIG_IPV6_PRIVACY
	.use_tempaddr		= 0,
	.temp_valid_lft		= TEMP_VALID_LIFETIME,
	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
	.regen_max_retry	= REGEN_MAX_RETRY,
	.max_desync_factor	= MAX_DESYNC_FACTOR,
#endif
	.max_addresses		= IPV6_MAX_ADDRESSES,
};

/* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
#if 0
const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
#endif
const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;

int ipv6_addr_type(const struct in6_addr *addr)
{
	int type;
	u32 st;

	st = addr->s6_addr32[0];

	if ((st & htonl(0xFF000000)) == htonl(0xFF000000)) {
		type = IPV6_ADDR_MULTICAST;

		switch((st & htonl(0x00FF0000))) {
			case __constant_htonl(0x00010000):
				type |= IPV6_ADDR_LOOPBACK;
				break;

			case __constant_htonl(0x00020000):
				type |= IPV6_ADDR_LINKLOCAL;
				break;

			case __constant_htonl(0x00050000):
				type |= IPV6_ADDR_SITELOCAL;
				break;
		};
		return type;
	}

	type = IPV6_ADDR_UNICAST;

	/* Consider all addresses with the first three bits different of
	   000 and 111 as finished.
	 */
	if ((st & htonl(0xE0000000)) != htonl(0x00000000) &&
	    (st & htonl(0xE0000000)) != htonl(0xE0000000))
		return type;
	
	if ((st & htonl(0xFFC00000)) == htonl(0xFE800000))
		return (IPV6_ADDR_LINKLOCAL | type);

	if ((st & htonl(0xFFC00000)) == htonl(0xFEC00000))
		return (IPV6_ADDR_SITELOCAL | type);

	if ((addr->s6_addr32[0] | addr->s6_addr32[1]) == 0) {
		if (addr->s6_addr32[2] == 0) {
			if (addr->s6_addr32[3] == 0)
				return IPV6_ADDR_ANY;

			if (addr->s6_addr32[3] == htonl(0x00000001))
				return (IPV6_ADDR_LOOPBACK | type);

			return (IPV6_ADDR_COMPATv4 | type);
		}

		if (addr->s6_addr32[2] == htonl(0x0000ffff))
			return IPV6_ADDR_MAPPED;
	}

	st &= htonl(0xFF000000);
	if (st == 0)
		return IPV6_ADDR_RESERVED;
	st &= htonl(0xFE000000);
	if (st == htonl(0x02000000))
		return IPV6_ADDR_RESERVED;	/* for NSAP */
	if (st == htonl(0x04000000))
		return IPV6_ADDR_RESERVED;	/* for IPX */
	return type;
}

static void addrconf_del_timer(struct inet6_ifaddr *ifp)
{
	if (del_timer(&ifp->timer))
		__in6_ifa_put(ifp);
}

enum addrconf_timer_t
{
	AC_NONE,
	AC_DAD,
	AC_RS,
};

static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
			       enum addrconf_timer_t what,
			       unsigned long when)
{
	if (!del_timer(&ifp->timer))
		in6_ifa_hold(ifp);

	switch (what) {
	case AC_DAD:
		ifp->timer.function = addrconf_dad_timer;
		break;
	case AC_RS:
		ifp->timer.function = addrconf_rs_timer;
		break;
	default:;
	}
	ifp->timer.expires = jiffies + when;
	add_timer(&ifp->timer);
}

/* Nobody refers to this device, we may destroy it. */

void in6_dev_finish_destroy(struct inet6_dev *idev)
{
	struct net_device *dev = idev->dev;
	BUG_TRAP(idev->addr_list==NULL);
	BUG_TRAP(idev->mc_list==NULL);
#ifdef NET_REFCNT_DEBUG
	printk(KERN_DEBUG "in6_dev_finish_destroy: %s\n", dev ? dev->name : "NIL");
#endif
	dev_put(dev);
	if (!idev->dead) {
		printk("Freeing alive inet6 device %p\n", idev);
		return;
	}
	snmp6_free_dev(idev);
	kfree(idev);
}

static struct inet6_dev * ipv6_add_dev(struct net_device *dev)
{
	struct inet6_dev *ndev;

	ASSERT_RTNL();

	if (dev->mtu < IPV6_MIN_MTU)
		return NULL;

	ndev = kmalloc(sizeof(struct inet6_dev), GFP_KERNEL);

	if (ndev) {
		memset(ndev, 0, sizeof(struct inet6_dev));

		rwlock_init(&ndev->lock);
		ndev->dev = dev;
		memcpy(&ndev->cnf, &ipv6_devconf_dflt, sizeof(ndev->cnf));
		ndev->cnf.mtu6 = dev->mtu;
		ndev->cnf.sysctl = NULL;
		ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
		if (ndev->nd_parms == NULL) {
			kfree(ndev);
			return NULL;
		}
		/* We refer to the device */
		dev_hold(dev);

		if (snmp6_alloc_dev(ndev) < 0) {
			ADBG((KERN_WARNING
				"%s(): cannot allocate memory for statistics; dev=%s.\n",
				__FUNCTION__, dev->name));
			neigh_parms_release(&nd_tbl, ndev->nd_parms);
			ndev->dead = 1;
			in6_dev_finish_destroy(ndev);
			return NULL;
		}

		if (snmp6_register_dev(ndev) < 0) {
			ADBG((KERN_WARNING
				"%s(): cannot create /proc/net/dev_snmp6/%s\n",
				__FUNCTION__, dev->name));
			neigh_parms_release(&nd_tbl, ndev->nd_parms);
			ndev->dead = 1;
			in6_dev_finish_destroy(ndev);
			return NULL;
		}

		/* One reference from device.  We must do this before
		 * we invoke __ipv6_regen_rndid().
		 */
		in6_dev_hold(ndev);

#ifdef CONFIG_IPV6_PRIVACY
		get_random_bytes(ndev->rndid, sizeof(ndev->rndid));
		get_random_bytes(ndev->entropy, sizeof(ndev->entropy));
		init_timer(&ndev->regen_timer);
		ndev->regen_timer.function = ipv6_regen_rndid;
		ndev->regen_timer.data = (unsigned long) ndev;
		if ((dev->flags&IFF_LOOPBACK) ||
		    dev->type == ARPHRD_TUNNEL ||
Commit	Line	Data
1da177e4 LT	1	/*
	2	* IPv6 Address [auto]configuration
	3	* Linux INET6 implementation
	4	*
	5	* Authors:
	6	* Pedro Roque <roque@di.fc.ul.pt>
	7	* Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
	8	*
	9	* $Id: addrconf.c,v 1.69 2001/10/31 21:55:54 davem Exp $
	10	*
	11	* This program is free software; you can redistribute it and/or
	12	* modify it under the terms of the GNU General Public License
	13	* as published by the Free Software Foundation; either version
	14	* 2 of the License, or (at your option) any later version.
	15	*/
	16
	17	/*
	18	* Changes:
	19	*
	20	* Janos Farkas : delete timer on ifdown
	21	* <chexum@bankinf.banki.hu>
	22	* Andi Kleen : kill double kfree on module
	23	* unload.
	24	* Maciej W. Rozycki : FDDI support
	25	* sekiya@USAGI : Don't send too many RS
	26	* packets.
	27	* yoshfuji@USAGI : Fixed interval between DAD
	28	* packets.
	29	* YOSHIFUJI Hideaki @USAGI : improved accuracy of
	30	* address validation timer.
	31	* YOSHIFUJI Hideaki @USAGI : Privacy Extensions (RFC3041)
	32	* support.
	33	* Yuji SEKIYA @USAGI : Don't assign a same IPv6
	34	* address on a same interface.
	35	* YOSHIFUJI Hideaki @USAGI : ARCnet support
	36	* YOSHIFUJI Hideaki @USAGI : convert /proc/net/if_inet6 to
	37	* seq_file.
	38	*/
	39
	40	#include <linux/config.h>
	41	#include <linux/errno.h>
	42	#include <linux/types.h>
	43	#include <linux/socket.h>
	44	#include <linux/sockios.h>
	45	#include <linux/sched.h>
	46	#include <linux/net.h>
	47	#include <linux/in6.h>
	48	#include <linux/netdevice.h>
	49	#include <linux/if_arp.h>
	50	#include <linux/if_arcnet.h>
	51	#include <linux/if_infiniband.h>
	52	#include <linux/route.h>
	53	#include <linux/inetdevice.h>
	54	#include <linux/init.h>
	55	#ifdef CONFIG_SYSCTL
	56	#include <linux/sysctl.h>
	57	#endif
	58	#include <linux/delay.h>
	59	#include <linux/notifier.h>
543537bd	60	#include <linux/string.h>
1da177e4 LT	61
	62	#include <net/sock.h>
	63	#include <net/snmp.h>
	64
	65	#include <net/ipv6.h>
	66	#include <net/protocol.h>
	67	#include <net/ndisc.h>
	68	#include <net/ip6_route.h>
	69	#include <net/addrconf.h>
	70	#include <net/tcp.h>
	71	#include <net/ip.h>
	72	#include <linux/if_tunnel.h>
	73	#include <linux/rtnetlink.h>
	74
	75	#ifdef CONFIG_IPV6_PRIVACY
	76	#include <linux/random.h>
	77	#include <linux/crypto.h>
	78	#include <asm/scatterlist.h>
	79	#endif
	80
	81	#include <asm/uaccess.h>
	82
	83	#include <linux/proc_fs.h>
	84	#include <linux/seq_file.h>
	85
	86	/* Set to 3 to get tracing... */
	87	#define ACONF_DEBUG 2
	88
	89	#if ACONF_DEBUG >= 3
	90	#define ADBG(x) printk x
	91	#else
	92	#define ADBG(x)
	93	#endif
	94
	95	#define INFINITY_LIFE_TIME 0xFFFFFFFF
	96	#define TIME_DELTA(a,b) ((unsigned long)((long)(a) - (long)(b)))
	97
	98	#ifdef CONFIG_SYSCTL
	99	static void addrconf_sysctl_register(struct inet6_dev idev, struct ipv6_devconf p);
	100	static void addrconf_sysctl_unregister(struct ipv6_devconf *p);
	101	#endif
	102
	103	#ifdef CONFIG_IPV6_PRIVACY
	104	static int __ipv6_regen_rndid(struct inet6_dev *idev);
	105	static int __ipv6_try_regen_rndid(struct inet6_dev idev, struct in6_addr tmpaddr);
	106	static void ipv6_regen_rndid(unsigned long data);
	107
	108	static int desync_factor = MAX_DESYNC_FACTOR * HZ;
	109	static struct crypto_tfm *md5_tfm;
	110	static DEFINE_SPINLOCK(md5_tfm_lock);
	111	#endif
	112
	113	static int ipv6_count_addresses(struct inet6_dev *idev);
	114
	115	/*
	116	* Configured unicast address hash table
	117	*/
	118	static struct inet6_ifaddr *inet6_addr_lst[IN6_ADDR_HSIZE];
	119	static DEFINE_RWLOCK(addrconf_hash_lock);
	120
	121	/* Protects inet6 devices */
	122	DEFINE_RWLOCK(addrconf_lock);
	123
	124	static void addrconf_verify(unsigned long);
125
8d06afab	126	static DEFINE_TIMER(addr_chk_timer, addrconf_verify, 0, 0);
1da177e4 LT	127	static DEFINE_SPINLOCK(addrconf_verify_lock);
	128
	129	static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
	130	static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
	131
	132	static int addrconf_ifdown(struct net_device *dev, int how);
	133
e431b8c0	134	static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags);
1da177e4 LT	135	static void addrconf_dad_timer(unsigned long data);
	136	static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
	137	static void addrconf_rs_timer(unsigned long data);
	138	static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
	139	static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
	140
	141	static void inet6_prefix_notify(int event, struct inet6_dev *idev,
	142	struct prefix_info *pinfo);
	143	static int ipv6_chk_same_addr(const struct in6_addr addr, struct net_device dev);
	144
	145	static struct notifier_block *inet6addr_chain;
	146
	147	struct ipv6_devconf ipv6_devconf = {
	148	.forwarding = 0,
	149	.hop_limit = IPV6_DEFAULT_HOPLIMIT,
	150	.mtu6 = IPV6_MIN_MTU,
	151	.accept_ra = 1,
	152	.accept_redirects = 1,
	153	.autoconf = 1,
	154	.force_mld_version = 0,
	155	.dad_transmits = 1,
	156	.rtr_solicits = MAX_RTR_SOLICITATIONS,
	157	.rtr_solicit_interval = RTR_SOLICITATION_INTERVAL,
	158	.rtr_solicit_delay = MAX_RTR_SOLICITATION_DELAY,
	159	#ifdef CONFIG_IPV6_PRIVACY
	160	.use_tempaddr = 0,
	161	.temp_valid_lft = TEMP_VALID_LIFETIME,
	162	.temp_prefered_lft = TEMP_PREFERRED_LIFETIME,
	163	.regen_max_retry = REGEN_MAX_RETRY,
	164	.max_desync_factor = MAX_DESYNC_FACTOR,
	165	#endif
	166	.max_addresses = IPV6_MAX_ADDRESSES,
	167	};
	168
	169	static struct ipv6_devconf ipv6_devconf_dflt = {
	170	.forwarding = 0,
	171	.hop_limit = IPV6_DEFAULT_HOPLIMIT,
	172	.mtu6 = IPV6_MIN_MTU,
	173	.accept_ra = 1,
	174	.accept_redirects = 1,
	175	.autoconf = 1,
	176	.dad_transmits = 1,
	177	.rtr_solicits = MAX_RTR_SOLICITATIONS,
	178	.rtr_solicit_interval = RTR_SOLICITATION_INTERVAL,
	179	.rtr_solicit_delay = MAX_RTR_SOLICITATION_DELAY,
	180	#ifdef CONFIG_IPV6_PRIVACY
	181	.use_tempaddr = 0,
	182	.temp_valid_lft = TEMP_VALID_LIFETIME,
	183	.temp_prefered_lft = TEMP_PREFERRED_LIFETIME,
	184	.regen_max_retry = REGEN_MAX_RETRY,
	185	.max_desync_factor = MAX_DESYNC_FACTOR,
	186	#endif
	187	.max_addresses = IPV6_MAX_ADDRESSES,
	188	};
	189
	190	/* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
	191	#if 0
	192	const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
	193	#endif
	194	const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
	195
	196	int ipv6_addr_type(const struct in6_addr *addr)
	197	{
	198	int type;
199	u32 st;
200
201	st = addr->s6_addr32[0];
202
203	if ((st & htonl(0xFF000000)) == htonl(0xFF000000)) {
204	type = IPV6_ADDR_MULTICAST;
205
206	switch((st & htonl(0x00FF0000))) {
207	case __constant_htonl(0x00010000):
208	type \|= IPV6_ADDR_LOOPBACK;
209	break;
210
211	case __constant_htonl(0x00020000):
212	type \|= IPV6_ADDR_LINKLOCAL;
213	break;
214
215	case __constant_htonl(0x00050000):
216	type \|= IPV6_ADDR_SITELOCAL;
217	break;
218	};
219	return type;
220	}
221
222	type = IPV6_ADDR_UNICAST;
223
224	/* Consider all addresses with the first three bits different of
225	000 and 111 as finished.
226	*/
227	if ((st & htonl(0xE0000000)) != htonl(0x00000000) &&
228	(st & htonl(0xE0000000)) != htonl(0xE0000000))
229	return type;
230
231	if ((st & htonl(0xFFC00000)) == htonl(0xFE800000))
232	return (IPV6_ADDR_LINKLOCAL \| type);
233
234	if ((st & htonl(0xFFC00000)) == htonl(0xFEC00000))
235	return (IPV6_ADDR_SITELOCAL \| type);
236
237	if ((addr->s6_addr32[0] \| addr->s6_addr32[1]) == 0) {
238	if (addr->s6_addr32[2] == 0) {
239	if (addr->s6_addr32[3] == 0)
240	return IPV6_ADDR_ANY;
241
242	if (addr->s6_addr32[3] == htonl(0x00000001))
243	return (IPV6_ADDR_LOOPBACK \| type);
244
245	return (IPV6_ADDR_COMPATv4 \| type);
246	}
247
248	if (addr->s6_addr32[2] == htonl(0x0000ffff))
249	return IPV6_ADDR_MAPPED;
250	}
251
252	st &= htonl(0xFF000000);
253	if (st == 0)
254	return IPV6_ADDR_RESERVED;
255	st &= htonl(0xFE000000);
256	if (st == htonl(0x02000000))
257	return IPV6_ADDR_RESERVED; /* for NSAP */
258	if (st == htonl(0x04000000))
259	return IPV6_ADDR_RESERVED; /* for IPX */
260	return type;
261	}
262
263	static void addrconf_del_timer(struct inet6_ifaddr *ifp)
264	{
265	if (del_timer(&ifp->timer))
266	__in6_ifa_put(ifp);
267	}
268
269	enum addrconf_timer_t
270	{
271	AC_NONE,
272	AC_DAD,
273	AC_RS,
274	};
275
276	static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
277	enum addrconf_timer_t what,
278	unsigned long when)
279	{
280	if (!del_timer(&ifp->timer))
281	in6_ifa_hold(ifp);
282
283	switch (what) {
284	case AC_DAD:
285	ifp->timer.function = addrconf_dad_timer;
286	break;
287	case AC_RS:
288	ifp->timer.function = addrconf_rs_timer;
289	break;
290	default:;
291	}
292	ifp->timer.expires = jiffies + when;
293	add_timer(&ifp->timer);
294	}
295
296	/* Nobody refers to this device, we may destroy it. */
297
298	void in6_dev_finish_destroy(struct inet6_dev *idev)
299	{
300	struct net_device *dev = idev->dev;
301	BUG_TRAP(idev->addr_list==NULL);
302	BUG_TRAP(idev->mc_list==NULL);
303	#ifdef NET_REFCNT_DEBUG
304	printk(KERN_DEBUG "in6_dev_finish_destroy: %s\n", dev ? dev->name : "NIL");
305	#endif
306	dev_put(dev);
307	if (!idev->dead) {
308	printk("Freeing alive inet6 device %p\n", idev);
309	return;
310	}
311	snmp6_free_dev(idev);
312	kfree(idev);
313	}
314
315	static struct inet6_dev * ipv6_add_dev(struct net_device *dev)
316	{
317	struct inet6_dev *ndev;
318
319	ASSERT_RTNL();
320
321	if (dev->mtu < IPV6_MIN_MTU)
322	return NULL;
323
324	ndev = kmalloc(sizeof(struct inet6_dev), GFP_KERNEL);
325
326	if (ndev) {
327	memset(ndev, 0, sizeof(struct inet6_dev));
328
329	rwlock_init(&ndev->lock);
330	ndev->dev = dev;
331	memcpy(&ndev->cnf, &ipv6_devconf_dflt, sizeof(ndev->cnf));
332	ndev->cnf.mtu6 = dev->mtu;
333	ndev->cnf.sysctl = NULL;
334	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
335	if (ndev->nd_parms == NULL) {
336	kfree(ndev);
337	return NULL;
338	}
339	/* We refer to the device */
340	dev_hold(dev);
341
342	if (snmp6_alloc_dev(ndev) < 0) {
343	ADBG((KERN_WARNING
344	"%s(): cannot allocate memory for statistics; dev=%s.\n",
345	__FUNCTION__, dev->name));
346	neigh_parms_release(&nd_tbl, ndev->nd_parms);
347	ndev->dead = 1;
348	in6_dev_finish_destroy(ndev);
349	return NULL;
350	}
351
352	if (snmp6_register_dev(ndev) < 0) {
353	ADBG((KERN_WARNING
354	"%s(): cannot create /proc/net/dev_snmp6/%s\n",
355	__FUNCTION__, dev->name));
356	neigh_parms_release(&nd_tbl, ndev->nd_parms);
357	ndev->dead = 1;
358	in6_dev_finish_destroy(ndev);
359	return NULL;
360	}
361
362	/* One reference from device. We must do this before
363	* we invoke __ipv6_regen_rndid().
364	*/
365	in6_dev_hold(ndev);
366
367	#ifdef CONFIG_IPV6_PRIVACY
368	get_random_bytes(ndev->rndid, sizeof(ndev->rndid));
369	get_random_bytes(ndev->entropy, sizeof(ndev->entropy));
370	init_timer(&ndev->regen_timer);
371	ndev->regen_timer.function = ipv6_regen_rndid;
372	ndev->regen_timer.data = (unsigned long) ndev;
373	if ((dev->flags&IFF_LOOPBACK) \|\|
374	dev->type == ARPHRD_TUNNEL \|\|