addrconf.c

Linux Kernel 2.6.9 for OMAP1710

	struct inet6_dev *idev;
	struct net_device *dev;
	
	if ((dev = __dev_get_by_index(ifindex)) == NULL)
		return -ENODEV;

	if ((idev = __in6_dev_get(dev)) == NULL)
		return -ENXIO;

	read_lock_bh(&idev->lock);
	for (ifp = idev->addr_list; ifp; ifp=ifp->if_next) {
		if (ifp->prefix_len == plen &&
		    (!memcmp(pfx, &ifp->addr, sizeof(struct in6_addr)))) {
			in6_ifa_hold(ifp);
			read_unlock_bh(&idev->lock);
			
			ipv6_del_addr(ifp);

			/* If the last address is deleted administratively,
			   disable IPv6 on this interface.
			 */
			if (idev->addr_list == NULL)
				addrconf_ifdown(idev->dev, 1);
			return 0;
		}
	}
	read_unlock_bh(&idev->lock);
	return -EADDRNOTAVAIL;
}


int addrconf_add_ifaddr(void __user *arg)
{
	struct in6_ifreq ireq;
	int err;
	
	if (!capable(CAP_NET_ADMIN))
		return -EPERM;
	
	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
		return -EFAULT;

	rtnl_lock();
	err = inet6_addr_add(ireq.ifr6_ifindex, &ireq.ifr6_addr, ireq.ifr6_prefixlen);
	rtnl_unlock();
	return err;
}

int addrconf_del_ifaddr(void __user *arg)
{
	struct in6_ifreq ireq;
	int err;
	
	if (!capable(CAP_NET_ADMIN))
		return -EPERM;

	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
		return -EFAULT;

	rtnl_lock();
	err = inet6_addr_del(ireq.ifr6_ifindex, &ireq.ifr6_addr, ireq.ifr6_prefixlen);
	rtnl_unlock();
	return err;
}

static void sit_add_v4_addrs(struct inet6_dev *idev)
{
	struct inet6_ifaddr * ifp;
	struct in6_addr addr;
	struct net_device *dev;
	int scope;

	ASSERT_RTNL();

	memset(&addr, 0, sizeof(struct in6_addr));
	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);

	if (idev->dev->flags&IFF_POINTOPOINT) {
		addr.s6_addr32[0] = htonl(0xfe800000);
		scope = IFA_LINK;
	} else {
		scope = IPV6_ADDR_COMPATv4;
	}

	if (addr.s6_addr32[3]) {
		ifp = ipv6_add_addr(idev, &addr, 128, scope, IFA_F_PERMANENT);
		if (!IS_ERR(ifp)) {
			spin_lock_bh(&ifp->lock);
			ifp->flags &= ~IFA_F_TENTATIVE;
			spin_unlock_bh(&ifp->lock);
			ipv6_ifa_notify(RTM_NEWADDR, ifp);
			in6_ifa_put(ifp);
		}
		return;
	}

        for (dev = dev_base; dev != NULL; dev = dev->next) {
		struct in_device * in_dev = __in_dev_get(dev);
		if (in_dev && (dev->flags & IFF_UP)) {
			struct in_ifaddr * ifa;

			int flag = scope;

			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
				int plen;

				addr.s6_addr32[3] = ifa->ifa_local;

				if (ifa->ifa_scope == RT_SCOPE_LINK)
					continue;
				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
					if (idev->dev->flags&IFF_POINTOPOINT)
						continue;
					flag |= IFA_HOST;
				}
				if (idev->dev->flags&IFF_POINTOPOINT)
					plen = 64;
				else
					plen = 96;

				ifp = ipv6_add_addr(idev, &addr, plen, flag,
						    IFA_F_PERMANENT);
				if (!IS_ERR(ifp)) {
					spin_lock_bh(&ifp->lock);
					ifp->flags &= ~IFA_F_TENTATIVE;
					spin_unlock_bh(&ifp->lock);
					ipv6_ifa_notify(RTM_NEWADDR, ifp);
					in6_ifa_put(ifp);
				}
			}
		}
        }
}

static void init_loopback(struct net_device *dev)
{
	struct inet6_dev  *idev;
	struct inet6_ifaddr * ifp;

	/* ::1 */

	ASSERT_RTNL();

	if ((idev = ipv6_find_idev(dev)) == NULL) {
		printk(KERN_DEBUG "init loopback: add_dev failed\n");
		return;
	}

	ifp = ipv6_add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFA_F_PERMANENT);
	if (!IS_ERR(ifp)) {
		spin_lock_bh(&ifp->lock);
		ifp->flags &= ~IFA_F_TENTATIVE;
		spin_unlock_bh(&ifp->lock);
		ipv6_ifa_notify(RTM_NEWADDR, ifp);
		in6_ifa_put(ifp);
	}
}

static void addrconf_add_linklocal(struct inet6_dev *idev, struct in6_addr *addr)
{
	struct inet6_ifaddr * ifp;

	ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, IFA_F_PERMANENT);
	if (!IS_ERR(ifp)) {
		addrconf_dad_start(ifp, 0);
		in6_ifa_put(ifp);
	}
}

static void addrconf_dev_config(struct net_device *dev)
{
	struct in6_addr addr;
	struct inet6_dev    * idev;

	ASSERT_RTNL();

	if ((dev->type != ARPHRD_ETHER) && 
	    (dev->type != ARPHRD_FDDI) &&
	    (dev->type != ARPHRD_IEEE802_TR) &&
	    (dev->type != ARPHRD_ARCNET)) {
		/* Alas, we support only Ethernet autoconfiguration. */
		return;
	}

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

	memset(&addr, 0, sizeof(struct in6_addr));
	addr.s6_addr32[0] = htonl(0xFE800000);

	if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
		addrconf_add_linklocal(idev, &addr);
}

static void addrconf_sit_config(struct net_device *dev)
{
	struct inet6_dev *idev;

	ASSERT_RTNL();

	/* 
	 * Configure the tunnel with one of our IPv4 
	 * addresses... we should configure all of 
	 * our v4 addrs in the tunnel
	 */

	if ((idev = ipv6_find_idev(dev)) == NULL) {
		printk(KERN_DEBUG "init sit: add_dev failed\n");
		return;
	}

	sit_add_v4_addrs(idev);

	if (dev->flags&IFF_POINTOPOINT) {
		addrconf_add_mroute(dev);
		addrconf_add_lroute(dev);
	} else
		sit_route_add(dev);
}

static inline int
ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
{
	struct in6_addr lladdr;

	if (!ipv6_get_lladdr(link_dev, &lladdr)) {
		addrconf_add_linklocal(idev, &lladdr);
		return 0;
	}
	return -1;
}

static void ip6_tnl_add_linklocal(struct inet6_dev *idev)
{
	struct net_device *link_dev;

	/* first try to inherit the link-local address from the link device */
	if (idev->dev->iflink &&
	    (link_dev = __dev_get_by_index(idev->dev->iflink))) {
		if (!ipv6_inherit_linklocal(idev, link_dev))
			return;
	}
	/* then try to inherit it from any device */
	for (link_dev = dev_base; link_dev; link_dev = link_dev->next) {
		if (!ipv6_inherit_linklocal(idev, link_dev))
			return;
	}
	printk(KERN_DEBUG "init ip6-ip6: add_linklocal failed\n");
}

/*
 * Autoconfigure tunnel with a link-local address so routing protocols,
 * DHCPv6, MLD etc. can be run over the virtual link
 */

static void addrconf_ip6_tnl_config(struct net_device *dev)
{
	struct inet6_dev *idev;

	ASSERT_RTNL();

	if ((idev = addrconf_add_dev(dev)) == NULL) {
		printk(KERN_DEBUG "init ip6-ip6: add_dev failed\n");
		return;
	}
	ip6_tnl_add_linklocal(idev);
	addrconf_add_mroute(dev);
}

static int addrconf_notify(struct notifier_block *this, unsigned long event, 
			   void * data)
{
	struct net_device *dev = (struct net_device *) data;
	struct inet6_dev *idev = __in6_dev_get(dev);

	switch(event) {
	case NETDEV_UP:
		switch(dev->type) {
		case ARPHRD_SIT:
			addrconf_sit_config(dev);
			break;
		case ARPHRD_TUNNEL6:
			addrconf_ip6_tnl_config(dev);
			break;
		case ARPHRD_LOOPBACK:
			init_loopback(dev);
			break;

		default:
			addrconf_dev_config(dev);
			break;
		};
		if (idev) {
			/* If the MTU changed during the interface down, when the
			   interface up, the changed MTU must be reflected in the
			   idev as well as routers.
			 */
			if (idev->cnf.mtu6 != dev->mtu && dev->mtu >= IPV6_MIN_MTU) {
				rt6_mtu_change(dev, dev->mtu);
				idev->cnf.mtu6 = dev->mtu;
			}
			idev->tstamp = jiffies;
			inet6_ifinfo_notify(RTM_NEWLINK, idev);
			/* If the changed mtu during down is lower than IPV6_MIN_MTU
			   stop IPv6 on this interface.
			 */
			if (dev->mtu < IPV6_MIN_MTU)
				addrconf_ifdown(dev, event != NETDEV_DOWN);
		}
		break;

	case NETDEV_CHANGEMTU:
		if ( idev && dev->mtu >= IPV6_MIN_MTU) {
			rt6_mtu_change(dev, dev->mtu);
			idev->cnf.mtu6 = dev->mtu;
			break;
		}

		/* MTU falled under IPV6_MIN_MTU. Stop IPv6 on this interface. */

	case NETDEV_DOWN:
	case NETDEV_UNREGISTER:
		/*
		 *	Remove all addresses from this interface.
		 */
		addrconf_ifdown(dev, event != NETDEV_DOWN);
		break;
	case NETDEV_CHANGE:
		break;
	case NETDEV_CHANGENAME:
#ifdef CONFIG_SYSCTL
		if (idev) {
			addrconf_sysctl_unregister(&idev->cnf);
			neigh_sysctl_unregister(idev->nd_parms);
			neigh_sysctl_register(dev, idev->nd_parms, NET_IPV6, NET_IPV6_NEIGH, "ipv6", &ndisc_ifinfo_sysctl_change);
			addrconf_sysctl_register(idev, &idev->cnf);
		}
#endif
		break;
	};

	return NOTIFY_OK;
}

/*
 *	addrconf module should be notified of a device going up
 */
static struct notifier_block ipv6_dev_notf = {
	.notifier_call = addrconf_notify,
	.priority = 0
};

static int addrconf_ifdown(struct net_device *dev, int how)
{
	struct inet6_dev *idev;
	struct inet6_ifaddr *ifa, **bifa;
	int i;

	ASSERT_RTNL();

	rt6_ifdown(dev);
	neigh_ifdown(&nd_tbl, dev);

	idev = __in6_dev_get(dev);
	if (idev == NULL)
		return -ENODEV;

	/* Step 1: remove reference to ipv6 device from parent device.
	           Do not dev_put!
	 */
	if (how == 1) {
		write_lock_bh(&addrconf_lock);
		dev->ip6_ptr = NULL;
		idev->dead = 1;
		write_unlock_bh(&addrconf_lock);
	}

	/* Step 2: clear hash table */
	for (i=0; i<IN6_ADDR_HSIZE; i++) {
		bifa = &inet6_addr_lst[i];

		write_lock_bh(&addrconf_hash_lock);
		while ((ifa = *bifa) != NULL) {
			if (ifa->idev == idev) {
				*bifa = ifa->lst_next;
				ifa->lst_next = NULL;
				addrconf_del_timer(ifa);
				in6_ifa_put(ifa);
				continue;
			}
			bifa = &ifa->lst_next;
		}
		write_unlock_bh(&addrconf_hash_lock);
	}

	write_lock_bh(&idev->lock);

	/* Step 3: clear flags for stateless addrconf */
	if (how != 1)
		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD);

	/* Step 4: clear address list */
#ifdef CONFIG_IPV6_PRIVACY
	if (how == 1 && del_timer(&idev->regen_timer))
		in6_dev_put(idev);

	/* clear tempaddr list */
	while ((ifa = idev->tempaddr_list) != NULL) {
		idev->tempaddr_list = ifa->tmp_next;
		ifa->tmp_next = NULL;
		ifa->dead = 1;
		write_unlock_bh(&idev->lock);
		spin_lock_bh(&ifa->lock);

		if (ifa->ifpub) {
			in6_ifa_put(ifa->ifpub);
			ifa->ifpub = NULL;
		}
		spin_unlock_bh(&ifa->lock);
		in6_ifa_put(ifa);
		write_lock_bh(&idev->lock);
	}
#endif
	while ((ifa = idev->addr_list) != NULL) {
		idev->addr_list = ifa->if_next;
		ifa->if_next = NULL;
		ifa->dead = 1;
		addrconf_del_timer(ifa);
		write_unlock_bh(&idev->lock);

		ipv6_ifa_notify(RTM_DELADDR, ifa);
		in6_ifa_put(ifa);

		write_lock_bh(&idev->lock);
	}
	write_unlock_bh(&idev->lock);

	/* Step 5: Discard multicast list */

	if (how == 1)
		ipv6_mc_destroy_dev(idev);
	else
		ipv6_mc_down(idev);

	/* Step 5: netlink notification of this interface */
	idev->tstamp = jiffies;
	inet6_ifinfo_notify(RTM_NEWLINK, idev);
	
	/* Shot the device (if unregistered) */

	if (how == 1) {
#ifdef CONFIG_SYSCTL
		addrconf_sysctl_unregister(&idev->cnf);
		neigh_sysctl_unregister(idev->nd_parms);
#endif
		neigh_parms_release(&nd_tbl, idev->nd_parms);
		neigh_ifdown(&nd_tbl, dev);
		in6_dev_put(idev);
	}
	return 0;
}

static void addrconf_rs_timer(unsigned long data)
{
	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;

	if (ifp->idev->cnf.forwarding)
		goto out;

	if (ifp->idev->if_flags & IF_RA_RCVD) {
		/*
		 *	Announcement received after solicitation
		 *	was sent
		 */
		goto out;
	}

	spin_lock(&ifp->lock);
	if (ifp->probes++ < ifp->idev->cnf.rtr_solicits) {
		struct in6_addr all_routers;

		/* The wait after the last probe can be shorter */
		addrconf_mod_timer(ifp, AC_RS,
				   (ifp->probes == ifp->idev->cnf.rtr_solicits) ?
				   ifp->idev->cnf.rtr_solicit_delay :
				   ifp->idev->cnf.rtr_solicit_interval);
		spin_unlock(&ifp->lock);

		ipv6_addr_all_routers(&all_routers);

		ndisc_send_rs(ifp->idev->dev, &ifp->addr, &all_routers);
	} else {
		spin_unlock(&ifp->lock);
		/*
		 * Note: we do not support deprecated "all on-link"
		 * assumption any longer.
		 */
		printk(KERN_DEBUG "%s: no IPv6 routers present\n",
		       ifp->idev->dev->name);
	}

out:
	in6_ifa_put(ifp);
}

/*
 *	Duplicate Address Detection
 */
static void addrconf_dad_start(struct inet6_ifaddr *ifp, int flags)
{
	struct net_device *dev;
	unsigned long rand_num;

	dev = ifp->idev->dev;

	addrconf_join_solict(dev, &ifp->addr);

	if (ifp->prefix_len != 128 && (ifp->flags&IFA_F_PERMANENT))
		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev, 0,
					flags);

	net_srandom(ifp->addr.s6_addr32[3]);
	rand_num = net_random() % (ifp->idev->cnf.rtr_solicit_delay ? : 1);

	spin_lock_bh(&ifp->lock);

	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
	    !(ifp->flags&IFA_F_TENTATIVE)) {
		ifp->flags &= ~IFA_F_TENTATIVE;
		spin_unlock_bh(&ifp->lock);

		addrconf_dad_completed(ifp);
		return;
	}

	ifp->probes = ifp->idev->cnf.dad_transmits;
	addrconf_mod_timer(ifp, AC_DAD, rand_num);

	spin_unlock_bh(&ifp->lock);
}

static void addrconf_dad_timer(unsigned long data)
{