addrconf.c

Linux Kernel 2.6.9 for OMAP1710

	__ipv6_dev_ac_dec(ifp->idev, &addr);
}

static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
{
	switch (dev->type) {
	case ARPHRD_ETHER:
	case ARPHRD_FDDI:
	case ARPHRD_IEEE802_TR:
		if (dev->addr_len != ETH_ALEN)
			return -1;
		memcpy(eui, dev->dev_addr, 3);
		memcpy(eui + 5, dev->dev_addr+3, 3);
		eui[3] = 0xFF;
		eui[4] = 0xFE;
		eui[0] ^= 2;
		return 0;
	case ARPHRD_ARCNET:
		/* XXX: inherit EUI-64 from other interface -- yoshfuji */
		if (dev->addr_len != ARCNET_ALEN)
			return -1;
		memset(eui, 0, 7);
		eui[7] = *(u8*)dev->dev_addr;
		return 0;
	}
	return -1;
}

static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
{
	int err = -1;
	struct inet6_ifaddr *ifp;

	read_lock_bh(&idev->lock);
	for (ifp=idev->addr_list; ifp; ifp=ifp->if_next) {
		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
			memcpy(eui, ifp->addr.s6_addr+8, 8);
			err = 0;
			break;
		}
	}
	read_unlock_bh(&idev->lock);
	return err;
}

#ifdef CONFIG_IPV6_PRIVACY
/* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
static int __ipv6_regen_rndid(struct inet6_dev *idev)
{
	struct net_device *dev;
	struct scatterlist sg[2];

	sg[0].page = virt_to_page(idev->entropy);
	sg[0].offset = offset_in_page(idev->entropy);
	sg[0].length = 8;
	sg[1].page = virt_to_page(idev->work_eui64);
	sg[1].offset = offset_in_page(idev->work_eui64);
	sg[1].length = 8;

	dev = idev->dev;

	if (ipv6_generate_eui64(idev->work_eui64, dev)) {
		printk(KERN_INFO
			"__ipv6_regen_rndid(idev=%p): cannot get EUI64 identifier; use random bytes.\n",
			idev);
		get_random_bytes(idev->work_eui64, sizeof(idev->work_eui64));
	}
regen:
	spin_lock(&md5_tfm_lock);
	if (unlikely(md5_tfm == NULL)) {
		spin_unlock(&md5_tfm_lock);
		return -1;
	}
	crypto_digest_init(md5_tfm);
	crypto_digest_update(md5_tfm, sg, 2);
	crypto_digest_final(md5_tfm, idev->work_digest);
	spin_unlock(&md5_tfm_lock);

	memcpy(idev->rndid, &idev->work_digest[0], 8);
	idev->rndid[0] &= ~0x02;
	memcpy(idev->entropy, &idev->work_digest[8], 8);

	/*
	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
	 * check if generated address is not inappropriate
	 *
	 *  - Reserved subnet anycast (RFC 2526)
	 *	11111101 11....11 1xxxxxxx
	 *  - ISATAP (draft-ietf-ngtrans-isatap-13.txt) 5.1
	 *	00-00-5E-FE-xx-xx-xx-xx
	 *  - value 0
	 *  - XXX: already assigned to an address on the device
	 */
	if (idev->rndid[0] == 0xfd && 
	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
	    (idev->rndid[7]&0x80))
		goto regen;
	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
			goto regen;
		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
			goto regen;
	}

	return 0;
}

static void ipv6_regen_rndid(unsigned long data)
{
	struct inet6_dev *idev = (struct inet6_dev *) data;
	unsigned long expires;

	read_lock_bh(&addrconf_lock);
	write_lock_bh(&idev->lock);

	if (idev->dead)
		goto out;

	if (__ipv6_regen_rndid(idev) < 0)
		goto out;
	
	expires = jiffies +
		idev->cnf.temp_prefered_lft * HZ - 
		idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time - desync_factor;
	if (time_before(expires, jiffies)) {
		printk(KERN_WARNING
			"ipv6_regen_rndid(): too short regeneration interval; timer disabled for %s.\n",
			idev->dev->name);
		goto out;
	}

	if (!mod_timer(&idev->regen_timer, expires))
		in6_dev_hold(idev);

out:
	write_unlock_bh(&idev->lock);
	read_unlock_bh(&addrconf_lock);
	in6_dev_put(idev);
}

static int __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr) {
	int ret = 0;

	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
		ret = __ipv6_regen_rndid(idev);
	return ret;
}
#endif

/*
 *	Add prefix route.
 */

static void
addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
		      unsigned long expires, unsigned flags)
{
	struct in6_rtmsg rtmsg;

	memset(&rtmsg, 0, sizeof(rtmsg));
	ipv6_addr_copy(&rtmsg.rtmsg_dst, pfx);
	rtmsg.rtmsg_dst_len = plen;
	rtmsg.rtmsg_metric = IP6_RT_PRIO_ADDRCONF;
	rtmsg.rtmsg_ifindex = dev->ifindex;
	rtmsg.rtmsg_info = expires;
	rtmsg.rtmsg_flags = RTF_UP|flags;
	rtmsg.rtmsg_type = RTMSG_NEWROUTE;

	/* Prevent useless cloning on PtP SIT.
	   This thing is done here expecting that the whole
	   class of non-broadcast devices need not cloning.
	 */
	if (dev->type == ARPHRD_SIT && (dev->flags&IFF_POINTOPOINT))
		rtmsg.rtmsg_flags |= RTF_NONEXTHOP;

	ip6_route_add(&rtmsg, NULL, NULL);
}

/* Create "default" multicast route to the interface */

static void addrconf_add_mroute(struct net_device *dev)
{
	struct in6_rtmsg rtmsg;

	memset(&rtmsg, 0, sizeof(rtmsg));
	ipv6_addr_set(&rtmsg.rtmsg_dst,
		      htonl(0xFF000000), 0, 0, 0);
	rtmsg.rtmsg_dst_len = 8;
	rtmsg.rtmsg_metric = IP6_RT_PRIO_ADDRCONF;
	rtmsg.rtmsg_ifindex = dev->ifindex;
	rtmsg.rtmsg_flags = RTF_UP;
	rtmsg.rtmsg_type = RTMSG_NEWROUTE;
	ip6_route_add(&rtmsg, NULL, NULL);
}

static void sit_route_add(struct net_device *dev)
{
	struct in6_rtmsg rtmsg;

	memset(&rtmsg, 0, sizeof(rtmsg));

	rtmsg.rtmsg_type	= RTMSG_NEWROUTE;
	rtmsg.rtmsg_metric	= IP6_RT_PRIO_ADDRCONF;

	/* prefix length - 96 bits "::d.d.d.d" */
	rtmsg.rtmsg_dst_len	= 96;
	rtmsg.rtmsg_flags	= RTF_UP|RTF_NONEXTHOP;
	rtmsg.rtmsg_ifindex	= dev->ifindex;

	ip6_route_add(&rtmsg, NULL, NULL);
}

static void addrconf_add_lroute(struct net_device *dev)
{
	struct in6_addr addr;

	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
	addrconf_prefix_route(&addr, 64, dev, 0, 0);
}

static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
{
	struct inet6_dev *idev;

	ASSERT_RTNL();

	if ((idev = ipv6_find_idev(dev)) == NULL)
		return NULL;

	/* Add default multicast route */
	addrconf_add_mroute(dev);

	/* Add link local route */
	addrconf_add_lroute(dev);
	return idev;
}

void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len)
{
	struct prefix_info *pinfo;
	__u32 valid_lft;
	__u32 prefered_lft;
	int addr_type;
	unsigned long rt_expires;
	struct inet6_dev *in6_dev;

	pinfo = (struct prefix_info *) opt;
	
	if (len < sizeof(struct prefix_info)) {
		ADBG(("addrconf: prefix option too short\n"));
		return;
	}
	
	/*
	 *	Validation checks ([ADDRCONF], page 19)
	 */

	addr_type = ipv6_addr_type(&pinfo->prefix);

	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
		return;

	valid_lft = ntohl(pinfo->valid);
	prefered_lft = ntohl(pinfo->prefered);

	if (prefered_lft > valid_lft) {
		if (net_ratelimit())
			printk(KERN_WARNING "addrconf: prefix option has invalid lifetime\n");
		return;
	}

	in6_dev = in6_dev_get(dev);

	if (in6_dev == NULL) {
		if (net_ratelimit())
			printk(KERN_DEBUG "addrconf: device %s not configured\n", dev->name);
		return;
	}

	/*
	 *	Two things going on here:
	 *	1) Add routes for on-link prefixes
	 *	2) Configure prefixes with the auto flag set
	 */

	/* Avoid arithmetic overflow. Really, we could
	   save rt_expires in seconds, likely valid_lft,
	   but it would require division in fib gc, that it
	   not good.
	 */
	if (valid_lft >= 0x7FFFFFFF/HZ)
		rt_expires = 0;
	else
		rt_expires = jiffies + valid_lft * HZ;

	if (pinfo->onlink) {
		struct rt6_info *rt;
		rt = rt6_lookup(&pinfo->prefix, NULL, dev->ifindex, 1);

		if (rt && ((rt->rt6i_flags & (RTF_GATEWAY | RTF_DEFAULT)) == 0)) {
			if (rt->rt6i_flags&RTF_EXPIRES) {
				if (valid_lft == 0) {
					ip6_del_rt(rt, NULL, NULL);
					rt = NULL;
				} else {
					rt->rt6i_expires = rt_expires;
				}
			}
		} else if (valid_lft) {
			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
					      dev, rt_expires, RTF_ADDRCONF|RTF_EXPIRES|RTF_PREFIX_RT);
		}
		if (rt)
			dst_release(&rt->u.dst);
	}

	/* Try to figure out our local address for this prefix */

	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
		struct inet6_ifaddr * ifp;
		struct in6_addr addr;
		int create = 0, update_lft = 0;

		if (pinfo->prefix_len == 64) {
			memcpy(&addr, &pinfo->prefix, 8);
			if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
			    ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
				in6_dev_put(in6_dev);
				return;
			}
			goto ok;
		}
		if (net_ratelimit())
			printk(KERN_DEBUG "IPv6 addrconf: prefix with wrong length %d\n",
			       pinfo->prefix_len);
		in6_dev_put(in6_dev);
		return;

ok:

		ifp = ipv6_get_ifaddr(&addr, dev, 1);

		if (ifp == NULL && valid_lft) {
			int max_addresses = in6_dev->cnf.max_addresses;

			/* Do not allow to create too much of autoconfigured
			 * addresses; this would be too easy way to crash kernel.
			 */
			if (!max_addresses ||
			    ipv6_count_addresses(in6_dev) < max_addresses)
				ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len,
						    addr_type&IPV6_ADDR_SCOPE_MASK, 0);

			if (!ifp || IS_ERR(ifp)) {
				in6_dev_put(in6_dev);
				return;
			}

			update_lft = create = 1;
			ifp->cstamp = jiffies;
			addrconf_dad_start(ifp, RTF_ADDRCONF|RTF_PREFIX_RT);
		}

		if (ifp) {
			int flags;
			unsigned long now;
#ifdef CONFIG_IPV6_PRIVACY
			struct inet6_ifaddr *ift;
#endif
			u32 stored_lft;

			/* update lifetime (RFC2462 5.5.3 e) */
			spin_lock(&ifp->lock);
			now = jiffies;
			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
			else
				stored_lft = 0;
			if (!update_lft && stored_lft) {
				if (valid_lft > MIN_VALID_LIFETIME ||
				    valid_lft > stored_lft)
					update_lft = 1;
				else if (stored_lft <= MIN_VALID_LIFETIME) {
					/* valid_lft <= stored_lft is always true */
					/* XXX: IPsec */
					update_lft = 0;
				} else {
					valid_lft = MIN_VALID_LIFETIME;
					if (valid_lft < prefered_lft)
						prefered_lft = valid_lft;
					update_lft = 1;
				}
			}

			if (update_lft) {
				ifp->valid_lft = valid_lft;
				ifp->prefered_lft = prefered_lft;
				ifp->tstamp = now;
				flags = ifp->flags;
				ifp->flags &= ~IFA_F_DEPRECATED;
				spin_unlock(&ifp->lock);

				if (!(flags&IFA_F_TENTATIVE))
					ipv6_ifa_notify(0, ifp);
			} else
				spin_unlock(&ifp->lock);

#ifdef CONFIG_IPV6_PRIVACY
			read_lock_bh(&in6_dev->lock);
			/* update all temporary addresses in the list */
			for (ift=in6_dev->tempaddr_list; ift; ift=ift->tmp_next) {
				/*
				 * When adjusting the lifetimes of an existing
				 * temporary address, only lower the lifetimes.
				 * Implementations must not increase the
				 * lifetimes of an existing temporary address
				 * when processing a Prefix Information Option.
				 */
				spin_lock(&ift->lock);
				flags = ift->flags;
				if (ift->valid_lft > valid_lft &&
				    ift->valid_lft - valid_lft > (jiffies - ift->tstamp) / HZ)
					ift->valid_lft = valid_lft + (jiffies - ift->tstamp) / HZ;
				if (ift->prefered_lft > prefered_lft &&
				    ift->prefered_lft - prefered_lft > (jiffies - ift->tstamp) / HZ)
					ift->prefered_lft = prefered_lft + (jiffies - ift->tstamp) / HZ;
				spin_unlock(&ift->lock);
				if (!(flags&IFA_F_TENTATIVE))
					ipv6_ifa_notify(0, ift);
			}

			if (create && in6_dev->cnf.use_tempaddr > 0) {
				/*
				 * When a new public address is created as described in [ADDRCONF],
				 * also create a new temporary address.
				 */
				read_unlock_bh(&in6_dev->lock); 
				ipv6_create_tempaddr(ifp, NULL);
			} else {
				read_unlock_bh(&in6_dev->lock);
			}
#endif
			in6_ifa_put(ifp);
			addrconf_verify(0);
		}
	}
	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
	in6_dev_put(in6_dev);
}

/*
 *	Set destination address.
 *	Special case for SIT interfaces where we create a new "virtual"
 *	device.
 */
int addrconf_set_dstaddr(void __user *arg)
{
	struct in6_ifreq ireq;
	struct net_device *dev;
	int err = -EINVAL;

	rtnl_lock();

	err = -EFAULT;
	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
		goto err_exit;

	dev = __dev_get_by_index(ireq.ifr6_ifindex);

	err = -ENODEV;
	if (dev == NULL)
		goto err_exit;

	if (dev->type == ARPHRD_SIT) {
		struct ifreq ifr;
		mm_segment_t	oldfs;
		struct ip_tunnel_parm p;

		err = -EADDRNOTAVAIL;
		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
			goto err_exit;

		memset(&p, 0, sizeof(p));
		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
		p.iph.saddr = 0;
		p.iph.version = 4;
		p.iph.ihl = 5;
		p.iph.protocol = IPPROTO_IPV6;
		p.iph.ttl = 64;
		ifr.ifr_ifru.ifru_data = (void __user *)&p;

		oldfs = get_fs(); set_fs(KERNEL_DS);
		err = dev->do_ioctl(dev, &ifr, SIOCADDTUNNEL);
		set_fs(oldfs);

		if (err == 0) {
			err = -ENOBUFS;
			if ((dev = __dev_get_by_name(p.name)) == NULL)
				goto err_exit;
			err = dev_open(dev);
		}
	}

err_exit:
	rtnl_unlock();
	return err;
}

/*
 *	Manual configuration of address on an interface
 */
static int inet6_addr_add(int ifindex, struct in6_addr *pfx, int plen)
{
	struct inet6_ifaddr *ifp;
	struct inet6_dev *idev;
	struct net_device *dev;
	int scope;

	ASSERT_RTNL();
	
	if ((dev = __dev_get_by_index(ifindex)) == NULL)
		return -ENODEV;
	
	if (!(dev->flags&IFF_UP))
		return -ENETDOWN;

	if ((idev = addrconf_add_dev(dev)) == NULL)
		return -ENOBUFS;

	scope = ipv6_addr_scope(pfx);

	ifp = ipv6_add_addr(idev, pfx, plen, scope, IFA_F_PERMANENT);
	if (!IS_ERR(ifp)) {
		addrconf_dad_start(ifp, 0);
		in6_ifa_put(ifp);
		return 0;
	}

	return PTR_ERR(ifp);
}

static int inet6_addr_del(int ifindex, struct in6_addr *pfx, int plen)
{
	struct inet6_ifaddr *ifp;