[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / ipv6 / addrlabel.c

/*
 * IPv6 Address Label subsystem
 * for the IPv6 "Default" Source Address Selection
 *
 * Copyright (C)2007 USAGI/WIDE Project
 */
/*
 * Author:
 * 	YOSHIFUJI Hideaki @ USAGI/WIDE Project <yoshfuji@linux-ipv6.org>
 */

#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/rcupdate.h>
#include <linux/in6.h>
#include <linux/slab.h>
#include <net/addrconf.h>
#include <linux/if_addrlabel.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>

#if 0
#define ADDRLABEL(x...) printk(x)
#else
#define ADDRLABEL(x...) do { ; } while(0)
#endif

/*
 * Policy Table
 */
struct ip6addrlbl_entry
{
#ifdef CONFIG_NET_NS
	struct net *lbl_net;
#endif
	struct in6_addr prefix;
	int prefixlen;
	int ifindex;
	int addrtype;
	u32 label;
	struct hlist_node list;
	atomic_t refcnt;
	struct rcu_head rcu;
};

static struct ip6addrlbl_table
{
	struct hlist_head head;
	spinlock_t lock;
	u32 seq;
} ip6addrlbl_table;

static inline
struct net *ip6addrlbl_net(const struct ip6addrlbl_entry *lbl)
{
	return read_pnet(&lbl->lbl_net);
}

/*
 * Default policy table (RFC6724 + extensions)
 *
 * prefix		addr_type	label
 * -------------------------------------------------------------------------
 * ::1/128		LOOPBACK	0
 * ::/0			N/A		1
 * 2002::/16		N/A		2
 * ::/96		COMPATv4	3
 * ::ffff:0:0/96	V4MAPPED	4
 * fc00::/7		N/A		5		ULA (RFC 4193)
 * 2001::/32		N/A		6		Teredo (RFC 4380)
 * 2001:10::/28		N/A		7		ORCHID (RFC 4843)
 * fec0::/10		N/A		11		Site-local
 *							(deprecated by RFC3879)
 * 3ffe::/16		N/A		12		6bone
 *
 * Note: 0xffffffff is used if we do not have any policies.
 * Note: Labels for ULA and 6to4 are different from labels listed in RFC6724.
 */

#define IPV6_ADDR_LABEL_DEFAULT	0xffffffffUL

static const __net_initconst struct ip6addrlbl_init_table
{
	const struct in6_addr *prefix;
	int prefixlen;
	u32 label;
} ip6addrlbl_init_table[] = {
	{	/* ::/0 */
		.prefix = &in6addr_any,
		.label = 1,
	},{	/* fc00::/7 */
		.prefix = &(struct in6_addr){{{ 0xfc }}},
		.prefixlen = 7,
		.label = 5,
	},{	/* fec0::/10 */
		.prefix = &(struct in6_addr){{{ 0xfe, 0xc0 }}},
		.prefixlen = 10,
		.label = 11,
	},{	/* 2002::/16 */
		.prefix = &(struct in6_addr){{{ 0x20, 0x02 }}},
		.prefixlen = 16,
		.label = 2,
	},{	/* 3ffe::/16 */
		.prefix = &(struct in6_addr){{{ 0x3f, 0xfe }}},
		.prefixlen = 16,
		.label = 12,
	},{	/* 2001::/32 */
		.prefix = &(struct in6_addr){{{ 0x20, 0x01 }}},
		.prefixlen = 32,
		.label = 6,
	},{	/* 2001:10::/28 */
		.prefix = &(struct in6_addr){{{ 0x20, 0x01, 0x00, 0x10 }}},
		.prefixlen = 28,
		.label = 7,
	},{	/* ::ffff:0:0 */
		.prefix = &(struct in6_addr){{{ [10] = 0xff, [11] = 0xff }}},
		.prefixlen = 96,
		.label = 4,
	},{	/* ::/96 */
		.prefix = &in6addr_any,
		.prefixlen = 96,
		.label = 3,
	},{	/* ::1/128 */
		.prefix = &in6addr_loopback,
		.prefixlen = 128,
		.label = 0,
	}
};

/* Object management */
static inline void ip6addrlbl_free(struct ip6addrlbl_entry *p)
{
#ifdef CONFIG_NET_NS
	release_net(p->lbl_net);
#endif
	kfree(p);
}

static void ip6addrlbl_free_rcu(struct rcu_head *h)
{
	ip6addrlbl_free(container_of(h, struct ip6addrlbl_entry, rcu));
}

static bool ip6addrlbl_hold(struct ip6addrlbl_entry *p)
{
	return atomic_inc_not_zero(&p->refcnt);
}

static inline void ip6addrlbl_put(struct ip6addrlbl_entry *p)
{
	if (atomic_dec_and_test(&p->refcnt))
		call_rcu(&p->rcu, ip6addrlbl_free_rcu);
}

/* Find label */
static bool __ip6addrlbl_match(struct net *net,
			       const struct ip6addrlbl_entry *p,
			       const struct in6_addr *addr,
			       int addrtype, int ifindex)
{
	if (!net_eq(ip6addrlbl_net(p), net))
		return false;
	if (p->ifindex && p->ifindex != ifindex)
		return false;
	if (p->addrtype && p->addrtype != addrtype)
		return false;
	if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
		return false;
	return true;
}

static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
						  const struct in6_addr *addr,
						  int type, int ifindex)
{
	struct hlist_node *pos;
	struct ip6addrlbl_entry *p;
	hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
		if (__ip6addrlbl_match(net, p, addr, type, ifindex))
			return p;
	}
	return NULL;
}

u32 ipv6_addr_label(struct net *net,
		    const struct in6_addr *addr, int type, int ifindex)
{
	u32 label;
	struct ip6addrlbl_entry *p;

	type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;

	rcu_read_lock();
	p = __ipv6_addr_label(net, addr, type, ifindex);
	label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
	rcu_read_unlock();

	ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n",
		  __func__, addr, type, ifindex, label);

	return label;
}

/* allocate one entry */
static struct ip6addrlbl_entry *ip6addrlbl_alloc(struct net *net,
						 const struct in6_addr *prefix,
						 int prefixlen, int ifindex,
						 u32 label)
{
	struct ip6addrlbl_entry *newp;
	int addrtype;

	ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n",
		  __func__, prefix, prefixlen, ifindex, (unsigned int)label);

	addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK);

	switch (addrtype) {
	case IPV6_ADDR_MAPPED:
		if (prefixlen > 96)
			return ERR_PTR(-EINVAL);
		if (prefixlen < 96)
			addrtype = 0;
		break;
	case IPV6_ADDR_COMPATv4:
		if (prefixlen != 96)
			addrtype = 0;
		break;
	case IPV6_ADDR_LOOPBACK:
		if (prefixlen != 128)
			addrtype = 0;
		break;
	}

	newp = kmalloc(sizeof(*newp), GFP_KERNEL);
	if (!newp)
		return ERR_PTR(-ENOMEM);

	ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
	newp->prefixlen = prefixlen;
	newp->ifindex = ifindex;
	newp->addrtype = addrtype;
	newp->label = label;
	INIT_HLIST_NODE(&newp->list);
#ifdef CONFIG_NET_NS
	newp->lbl_net = hold_net(net);
#endif
	atomic_set(&newp->refcnt, 1);
	return newp;
}

/* add a label */
static int __ip6addrlbl_add(struct ip6addrlbl_entry *newp, int replace)
{
	int ret = 0;

	ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n",
			__func__,
			newp, replace);

	if (hlist_empty(&ip6addrlbl_table.head)) {
		hlist_add_head_rcu(&newp->list, &ip6addrlbl_table.head);
	} else {
		struct hlist_node *pos, *n;
		struct ip6addrlbl_entry *p = NULL;
		hlist_for_each_entry_safe(p, pos, n,
					  &ip6addrlbl_table.head, list) {
			if (p->prefixlen == newp->prefixlen &&
			    net_eq(ip6addrlbl_net(p), ip6addrlbl_net(newp)) &&
			    p->ifindex == newp->ifindex &&
			    ipv6_addr_equal(&p->prefix, &newp->prefix)) {
				if (!replace) {
					ret = -EEXIST;
					goto out;
				}
				hlist_replace_rcu(&p->list, &newp->list);
				ip6addrlbl_put(p);
				goto out;
			} else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
				   (p->prefixlen < newp->prefixlen)) {
				hlist_add_before_rcu(&newp->list, &p->list);
				goto out;
			}
		}
		hlist_add_after_rcu(&p->list, &newp->list);
	}
out:
	if (!ret)
		ip6addrlbl_table.seq++;
	return ret;
}

/* add a label */
static int ip6addrlbl_add(struct net *net,
			  const struct in6_addr *prefix, int prefixlen,
			  int ifindex, u32 label, int replace)
{
	struct ip6addrlbl_entry *newp;
	int ret = 0;

	ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
		  __func__, prefix, prefixlen, ifindex, (unsigned int)label,
		  replace);

	newp = ip6addrlbl_alloc(net, prefix, prefixlen, ifindex, label);
	if (IS_ERR(newp))
		return PTR_ERR(newp);
	spin_lock(&ip6addrlbl_table.lock);
	ret = __ip6addrlbl_add(newp, replace);
	spin_unlock(&ip6addrlbl_table.lock);
	if (ret)
		ip6addrlbl_free(newp);
	return ret;
}

/* remove a label */
static int __ip6addrlbl_del(struct net *net,
			    const struct in6_addr *prefix, int prefixlen,
			    int ifindex)
{
	struct ip6addrlbl_entry *p = NULL;
	struct hlist_node *pos, *n;
	int ret = -ESRCH;

	ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
		  __func__, prefix, prefixlen, ifindex);

	hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
		if (p->prefixlen == prefixlen &&
		    net_eq(ip6addrlbl_net(p), net) &&
		    p->ifindex == ifindex &&
		    ipv6_addr_equal(&p->prefix, prefix)) {
			hlist_del_rcu(&p->list);
			ip6addrlbl_put(p);
			ret = 0;
			break;
		}
	}
	return ret;
}

static int ip6addrlbl_del(struct net *net,
			  const struct in6_addr *prefix, int prefixlen,
			  int ifindex)
{
	struct in6_addr prefix_buf;
	int ret;

	ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
		  __func__, prefix, prefixlen, ifindex);

	ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
	spin_lock(&ip6addrlbl_table.lock);
	ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
	spin_unlock(&ip6addrlbl_table.lock);
	return ret;
}

/* add default label */
static int __net_init ip6addrlbl_net_init(struct net *net)
{
	int err = 0;
	int i;

	ADDRLABEL(KERN_DEBUG "%s\n", __func__);

	for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
		int ret = ip6addrlbl_add(net,
					 ip6addrlbl_init_table[i].prefix,
					 ip6addrlbl_init_table[i].prefixlen,
					 0,
					 ip6addrlbl_init_table[i].label, 0);
		/* XXX: should we free all rules when we catch an error? */
		if (ret && (!err || err != -ENOMEM))
			err = ret;
	}
	return err;
}

static void __net_exit ip6addrlbl_net_exit(struct net *net)
{
	struct ip6addrlbl_entry *p = NULL;
	struct hlist_node *pos, *n;

	/* Remove all labels belonging to the exiting net */
	spin_lock(&ip6addrlbl_table.lock);
	hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
		if (net_eq(ip6addrlbl_net(p), net)) {
			hlist_del_rcu(&p->list);
			ip6addrlbl_put(p);
		}
	}
	spin_unlock(&ip6addrlbl_table.lock);
}

static struct pernet_operations ipv6_addr_label_ops = {
	.init = ip6addrlbl_net_init,
	.exit = ip6addrlbl_net_exit,
};

int __init ipv6_addr_label_init(void)
{
	spin_lock_init(&ip6addrlbl_table.lock);

	return register_pernet_subsys(&ipv6_addr_label_ops);
}

void ipv6_addr_label_cleanup(void)
{
	unregister_pernet_subsys(&ipv6_addr_label_ops);
}

static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
	[IFAL_ADDRESS]		= { .len = sizeof(struct in6_addr), },
	[IFAL_LABEL]		= { .len = sizeof(u32), },
};

static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
			     void *arg)
{
	struct net *net = sock_net(skb->sk);
	struct ifaddrlblmsg *ifal;
	struct nlattr *tb[IFAL_MAX+1];
	struct in6_addr *pfx;
	u32 label;
	int err = 0;

	err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
	if (err < 0)
		return err;

	ifal = nlmsg_data(nlh);

	if (ifal->ifal_family != AF_INET6 ||
	    ifal->ifal_prefixlen > 128)
		return -EINVAL;

	if (!tb[IFAL_ADDRESS])
		return -EINVAL;

	pfx = nla_data(tb[IFAL_ADDRESS]);
	if (!pfx)
		return -EINVAL;

	if (!tb[IFAL_LABEL])
		return -EINVAL;
	label = nla_get_u32(tb[IFAL_LABEL]);
	if (label == IPV6_ADDR_LABEL_DEFAULT)
		return -EINVAL;

	switch(nlh->nlmsg_type) {
	case RTM_NEWADDRLABEL:
		if (ifal->ifal_index &&
		    !__dev_get_by_index(net, ifal->ifal_index))
			return -EINVAL;

		err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
				     ifal->ifal_index, label,
				     nlh->nlmsg_flags & NLM_F_REPLACE);
		break;
	case RTM_DELADDRLABEL:
		err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
				     ifal->ifal_index);
		break;
	default:
		err = -EOPNOTSUPP;
	}
	return err;
}

static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
			      int prefixlen, int ifindex, u32 lseq)
{
	struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
	ifal->ifal_family = AF_INET6;
	ifal->ifal_prefixlen = prefixlen;
	ifal->ifal_flags = 0;
	ifal->ifal_index = ifindex;
	ifal->ifal_seq = lseq;
};

static int ip6addrlbl_fill(struct sk_buff *skb,
			   struct ip6addrlbl_entry *p,
			   u32 lseq,
			   u32 portid, u32 seq, int event,
			   unsigned int flags)
{
	struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
					 sizeof(struct ifaddrlblmsg), flags);
	if (!nlh)
		return -EMSGSIZE;

	ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);

	if (nla_put(skb, IFAL_ADDRESS, 16, &p->prefix) < 0 ||
	    nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
		nlmsg_cancel(skb, nlh);
		return -EMSGSIZE;
	}

	return nlmsg_end(skb, nlh);
}

static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
	struct net *net = sock_net(skb->sk);
	struct ip6addrlbl_entry *p;
	struct hlist_node *pos;
	int idx = 0, s_idx = cb->args[0];
	int err;

	rcu_read_lock();
	hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
		if (idx >= s_idx &&
		    net_eq(ip6addrlbl_net(p), net)) {
			if ((err = ip6addrlbl_fill(skb, p,
						   ip6addrlbl_table.seq,
						   NETLINK_CB(cb->skb).portid,
						   cb->nlh->nlmsg_seq,
						   RTM_NEWADDRLABEL,
						   NLM_F_MULTI)) <= 0)
				break;
		}
		idx++;
	}
	rcu_read_unlock();
	cb->args[0] = idx;
	return skb->len;
}

static inline int ip6addrlbl_msgsize(void)
{
	return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
		+ nla_total_size(16)	/* IFAL_ADDRESS */
		+ nla_total_size(4);	/* IFAL_LABEL */
}

static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr* nlh,
			  void *arg)
{
	struct net *net = sock_net(in_skb->sk);
	struct ifaddrlblmsg *ifal;
	struct nlattr *tb[IFAL_MAX+1];
	struct in6_addr *addr;
	u32 lseq;
	int err = 0;
	struct ip6addrlbl_entry *p;
	struct sk_buff *skb;

	err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
	if (err < 0)
		return err;

	ifal = nlmsg_data(nlh);

	if (ifal->ifal_family != AF_INET6 ||
	    ifal->ifal_prefixlen != 128)
		return -EINVAL;

	if (ifal->ifal_index &&
	    !__dev_get_by_index(net, ifal->ifal_index))
		return -EINVAL;

	if (!tb[IFAL_ADDRESS])
		return -EINVAL;

	addr = nla_data(tb[IFAL_ADDRESS]);
	if (!addr)
		return -EINVAL;

	rcu_read_lock();
	p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
	if (p && ip6addrlbl_hold(p))
		p = NULL;
	lseq = ip6addrlbl_table.seq;
	rcu_read_unlock();

	if (!p) {
		err = -ESRCH;
		goto out;
	}

	if (!(skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL))) {
		ip6addrlbl_put(p);
		return -ENOBUFS;
	}

	err = ip6addrlbl_fill(skb, p, lseq,
			      NETLINK_CB(in_skb).portid, nlh->nlmsg_seq,
			      RTM_NEWADDRLABEL, 0);

	ip6addrlbl_put(p);

	if (err < 0) {
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(skb);
		goto out;
	}

	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
out:
	return err;
}

void __init ipv6_addr_label_rtnl_register(void)
{
	__rtnl_register(PF_INET6, RTM_NEWADDRLABEL, ip6addrlbl_newdel,
			NULL, NULL);
	__rtnl_register(PF_INET6, RTM_DELADDRLABEL, ip6addrlbl_newdel,
			NULL, NULL);
	__rtnl_register(PF_INET6, RTM_GETADDRLABEL, ip6addrlbl_get,
			ip6addrlbl_dump, NULL);
}
Commit	Line	Data
2a8cc6c8 YH	1	/*
	2	* IPv6 Address Label subsystem
	3	* for the IPv6 "Default" Source Address Selection
	4	*
	5	* Copyright (C)2007 USAGI/WIDE Project
	6	*/
	7	/*
	8	* Author:
	9	* YOSHIFUJI Hideaki @ USAGI/WIDE Project <yoshfuji@linux-ipv6.org>
	10	*/
	11
	12	#include <linux/kernel.h>
	13	#include <linux/list.h>
	14	#include <linux/rcupdate.h>
	15	#include <linux/in6.h>
5a0e3ad6	16	#include <linux/slab.h>
2a8cc6c8 YH	17	#include <net/addrconf.h>
	18	#include <linux/if_addrlabel.h>
	19	#include <linux/netlink.h>
	20	#include <linux/rtnetlink.h>
	21
	22	#if 0
	23	#define ADDRLABEL(x...) printk(x)
	24	#else
	25	#define ADDRLABEL(x...) do { ; } while(0)
	26	#endif
	27
	28	/*
	29	* Policy Table
	30	*/
	31	struct ip6addrlbl_entry
	32	{
3de23255 BT	33	#ifdef CONFIG_NET_NS
	34	struct net *lbl_net;
	35	#endif
2a8cc6c8 YH	36	struct in6_addr prefix;
	37	int prefixlen;
	38	int ifindex;
	39	int addrtype;
	40	u32 label;
	41	struct hlist_node list;
	42	atomic_t refcnt;
	43	struct rcu_head rcu;
	44	};
	45
	46	static struct ip6addrlbl_table
	47	{
	48	struct hlist_head head;
	49	spinlock_t lock;
	50	u32 seq;
	51	} ip6addrlbl_table;
	52
3de23255 BT	53	static inline
	54	struct net ip6addrlbl_net(const struct ip6addrlbl_entry lbl)
	55	{
c2d9ba9b	56	return read_pnet(&lbl->lbl_net);
3de23255 BT	57	}
3de23255 BT	58
2a8cc6c8	59	/*
417962a0	60	* Default policy table (RFC6724 + extensions)
2a8cc6c8 YH	61	*
	62	* prefix addr_type label
	63	* -------------------------------------------------------------------------
	64	* ::1/128 LOOPBACK 0
	65	* ::/0 N/A 1
	66	* 2002::/16 N/A 2
	67	* ::/96 COMPATv4 3
	68	* ::ffff:0:0/96 V4MAPPED 4
	69	* fc00::/7 N/A 5 ULA (RFC 4193)
	70	* 2001::/32 N/A 6 Teredo (RFC 4380)
5fe47b8a	71	* 2001:10::/28 N/A 7 ORCHID (RFC 4843)
417962a0 YH	72	* fec0::/10 N/A 11 Site-local
	73	* (deprecated by RFC3879)
	74	* 3ffe::/16 N/A 12 6bone
2a8cc6c8 YH	75	*
2a8cc6c8 YH	76	* Note: 0xffffffff is used if we do not have any policies.
417962a0	77	* Note: Labels for ULA and 6to4 are different from labels listed in RFC6724.
2a8cc6c8 YH	78	*/
	79
	80	#define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL
	81
04a6f82c	82	static const __net_initconst struct ip6addrlbl_init_table
2a8cc6c8 YH	83	{
	84	const struct in6_addr *prefix;
	85	int prefixlen;
	86	u32 label;
	87	} ip6addrlbl_init_table[] = {
	88	{ /* ::/0 */
	89	.prefix = &in6addr_any,
	90	.label = 1,
	91	},{ /* fc00::/7 */
	92	.prefix = &(struct in6_addr){{{ 0xfc }}},
	93	.prefixlen = 7,
	94	.label = 5,
417962a0 YH	95	},{ /* fec0::/10 */
	96	.prefix = &(struct in6_addr){{{ 0xfe, 0xc0 }}},
	97	.prefixlen = 10,
	98	.label = 11,
2a8cc6c8 YH	99	},{ /* 2002::/16 */
	100	.prefix = &(struct in6_addr){{{ 0x20, 0x02 }}},
	101	.prefixlen = 16,
	102	.label = 2,
417962a0 YH	103	},{ /* 3ffe::/16 */
	104	.prefix = &(struct in6_addr){{{ 0x3f, 0xfe }}},
	105	.prefixlen = 16,
	106	.label = 12,
2a8cc6c8 YH	107	},{ /* 2001::/32 */
	108	.prefix = &(struct in6_addr){{{ 0x20, 0x01 }}},
	109	.prefixlen = 32,
	110	.label = 6,
5fe47b8a JMT	111	},{ /* 2001:10::/28 */
	112	.prefix = &(struct in6_addr){{{ 0x20, 0x01, 0x00, 0x10 }}},
	113	.prefixlen = 28,
	114	.label = 7,
2a8cc6c8 YH	115	},{ /* ::ffff:0:0 */
	116	.prefix = &(struct in6_addr){{{ [10] = 0xff, [11] = 0xff }}},
	117	.prefixlen = 96,
	118	.label = 4,
	119	},{ /* ::/96 */
	120	.prefix = &in6addr_any,
	121	.prefixlen = 96,
	122	.label = 3,
	123	},{ /* ::1/128 */
	124	.prefix = &in6addr_loopback,
	125	.prefixlen = 128,
	126	.label = 0,
	127	}
	128	};
	129
	130	/* Object management */
	131	static inline void ip6addrlbl_free(struct ip6addrlbl_entry *p)
	132	{
3de23255 BT	133	#ifdef CONFIG_NET_NS
	134	release_net(p->lbl_net);
	135	#endif
2a8cc6c8 YH	136	kfree(p);
	137	}
	138
85040bcb YH	139	static void ip6addrlbl_free_rcu(struct rcu_head *h)
	140	{
	141	ip6addrlbl_free(container_of(h, struct ip6addrlbl_entry, rcu));
	142	}
	143
a50feda5	144	static bool ip6addrlbl_hold(struct ip6addrlbl_entry *p)
2a8cc6c8 YH	145	{
	146	return atomic_inc_not_zero(&p->refcnt);
	147	}
	148
	149	static inline void ip6addrlbl_put(struct ip6addrlbl_entry *p)
	150	{
	151	if (atomic_dec_and_test(&p->refcnt))
85040bcb	152	call_rcu(&p->rcu, ip6addrlbl_free_rcu);
2a8cc6c8 YH	153	}
	154
	155	/* Find label */
a50feda5 ED	156	static bool __ip6addrlbl_match(struct net *net,
	157	const struct ip6addrlbl_entry *p,
	158	const struct in6_addr *addr,
	159	int addrtype, int ifindex)
2a8cc6c8	160	{
3de23255	161	if (!net_eq(ip6addrlbl_net(p), net))
a50feda5	162	return false;
2a8cc6c8	163	if (p->ifindex && p->ifindex != ifindex)
a50feda5	164	return false;
2a8cc6c8	165	if (p->addrtype && p->addrtype != addrtype)
a50feda5	166	return false;
2a8cc6c8	167	if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
a50feda5 ED	168	return false;
a50feda5 ED	169	return true;
2a8cc6c8 YH	170	}
2a8cc6c8 YH	171
3de23255 BT	172	static struct ip6addrlbl_entry __ipv6_addr_label(struct net net,
3de23255 BT	173	const struct in6_addr *addr,
2a8cc6c8 YH	174	int type, int ifindex)
	175	{
	176	struct hlist_node *pos;
	177	struct ip6addrlbl_entry *p;
	178	hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
3de23255	179	if (__ip6addrlbl_match(net, p, addr, type, ifindex))
2a8cc6c8 YH	180	return p;
	181	}
	182	return NULL;
	183	}
	184
3de23255 BT	185	u32 ipv6_addr_label(struct net *net,
3de23255 BT	186	const struct in6_addr *addr, int type, int ifindex)
2a8cc6c8 YH	187	{
	188	u32 label;
	189	struct ip6addrlbl_entry *p;
	190
	191	type &= IPV6_ADDR_MAPPED \| IPV6_ADDR_COMPATv4 \| IPV6_ADDR_LOOPBACK;
	192
	193	rcu_read_lock();
3de23255	194	p = __ipv6_addr_label(net, addr, type, ifindex);
2a8cc6c8 YH	195	label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
	196	rcu_read_unlock();
	197
5b095d98	198	ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n",
0c6ce78a	199	__func__, addr, type, ifindex, label);
2a8cc6c8 YH	200
	201	return label;
	202	}
	203
	204	/* allocate one entry */
3de23255 BT	205	static struct ip6addrlbl_entry ip6addrlbl_alloc(struct net net,
3de23255 BT	206	const struct in6_addr *prefix,
40fee36e YH	207	int prefixlen, int ifindex,
40fee36e YH	208	u32 label)
2a8cc6c8 YH	209	{
	210	struct ip6addrlbl_entry *newp;
	211	int addrtype;
	212
5b095d98	213	ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n",
0c6ce78a	214	__func__, prefix, prefixlen, ifindex, (unsigned int)label);
2a8cc6c8 YH	215
	216	addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED \| IPV6_ADDR_COMPATv4 \| IPV6_ADDR_LOOPBACK);
	217
	218	switch (addrtype) {
	219	case IPV6_ADDR_MAPPED:
	220	if (prefixlen > 96)
	221	return ERR_PTR(-EINVAL);
	222	if (prefixlen < 96)
	223	addrtype = 0;
	224	break;
	225	case IPV6_ADDR_COMPATv4:
	226	if (prefixlen != 96)
	227	addrtype = 0;
	228	break;
	229	case IPV6_ADDR_LOOPBACK:
	230	if (prefixlen != 128)
	231	addrtype = 0;
	232	break;
	233	}
	234
	235	newp = kmalloc(sizeof(*newp), GFP_KERNEL);
	236	if (!newp)
	237	return ERR_PTR(-ENOMEM);
	238
	239	ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
	240	newp->prefixlen = prefixlen;
	241	newp->ifindex = ifindex;
	242	newp->addrtype = addrtype;
	243	newp->label = label;
	244	INIT_HLIST_NODE(&newp->list);
3de23255 BT	245	#ifdef CONFIG_NET_NS
	246	newp->lbl_net = hold_net(net);
	247	#endif
2a8cc6c8 YH	248	atomic_set(&newp->refcnt, 1);
	249	return newp;
	250	}
	251
	252	/* add a label */
40fee36e	253	static int __ip6addrlbl_add(struct ip6addrlbl_entry *newp, int replace)
2a8cc6c8 YH	254	{
	255	int ret = 0;
	256
	257	ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n",
0dc47877	258	__func__,
2a8cc6c8 YH	259	newp, replace);
	260
	261	if (hlist_empty(&ip6addrlbl_table.head)) {
	262	hlist_add_head_rcu(&newp->list, &ip6addrlbl_table.head);
	263	} else {
	264	struct hlist_node pos, n;
	265	struct ip6addrlbl_entry *p = NULL;
	266	hlist_for_each_entry_safe(p, pos, n,
	267	&ip6addrlbl_table.head, list) {
	268	if (p->prefixlen == newp->prefixlen &&
3de23255	269	net_eq(ip6addrlbl_net(p), ip6addrlbl_net(newp)) &&
2a8cc6c8 YH	270	p->ifindex == newp->ifindex &&
	271	ipv6_addr_equal(&p->prefix, &newp->prefix)) {
	272	if (!replace) {
	273	ret = -EEXIST;
	274	goto out;
	275	}
	276	hlist_replace_rcu(&p->list, &newp->list);
	277	ip6addrlbl_put(p);
2a8cc6c8 YH	278	goto out;
	279	} else if ((p->prefixlen == newp->prefixlen && !p->ifindex) \|\|
	280	(p->prefixlen < newp->prefixlen)) {
	281	hlist_add_before_rcu(&newp->list, &p->list);
	282	goto out;
	283	}
	284	}
	285	hlist_add_after_rcu(&p->list, &newp->list);
	286	}
	287	out:
	288	if (!ret)
	289	ip6addrlbl_table.seq++;
	290	return ret;
	291	}
	292
	293	/* add a label */
3de23255 BT	294	static int ip6addrlbl_add(struct net *net,
3de23255 BT	295	const struct in6_addr *prefix, int prefixlen,
40fee36e	296	int ifindex, u32 label, int replace)
2a8cc6c8 YH	297	{
	298	struct ip6addrlbl_entry *newp;
	299	int ret = 0;
	300
5b095d98	301	ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
0c6ce78a HH	302	__func__, prefix, prefixlen, ifindex, (unsigned int)label,
0c6ce78a HH	303	replace);
2a8cc6c8	304
3de23255	305	newp = ip6addrlbl_alloc(net, prefix, prefixlen, ifindex, label);
2a8cc6c8 YH	306	if (IS_ERR(newp))
	307	return PTR_ERR(newp);
	308	spin_lock(&ip6addrlbl_table.lock);
	309	ret = __ip6addrlbl_add(newp, replace);
	310	spin_unlock(&ip6addrlbl_table.lock);
	311	if (ret)
	312	ip6addrlbl_free(newp);
	313	return ret;
	314	}
	315
	316	/* remove a label */
3de23255 BT	317	static int __ip6addrlbl_del(struct net *net,
3de23255 BT	318	const struct in6_addr *prefix, int prefixlen,
40fee36e	319	int ifindex)
2a8cc6c8 YH	320	{
	321	struct ip6addrlbl_entry *p = NULL;
	322	struct hlist_node pos, n;
	323	int ret = -ESRCH;
	324
5b095d98	325	ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
0c6ce78a	326	__func__, prefix, prefixlen, ifindex);
2a8cc6c8 YH	327
	328	hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
	329	if (p->prefixlen == prefixlen &&
3de23255	330	net_eq(ip6addrlbl_net(p), net) &&
2a8cc6c8 YH	331	p->ifindex == ifindex &&
	332	ipv6_addr_equal(&p->prefix, prefix)) {
	333	hlist_del_rcu(&p->list);
	334	ip6addrlbl_put(p);
2a8cc6c8 YH	335	ret = 0;
	336	break;
	337	}
	338	}
	339	return ret;
	340	}
	341
3de23255 BT	342	static int ip6addrlbl_del(struct net *net,
3de23255 BT	343	const struct in6_addr *prefix, int prefixlen,
40fee36e	344	int ifindex)
2a8cc6c8 YH	345	{
	346	struct in6_addr prefix_buf;
	347	int ret;
	348
5b095d98	349	ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
0c6ce78a	350	__func__, prefix, prefixlen, ifindex);
2a8cc6c8 YH	351
	352	ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
	353	spin_lock(&ip6addrlbl_table.lock);
3de23255	354	ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
2a8cc6c8 YH	355	spin_unlock(&ip6addrlbl_table.lock);
	356	return ret;
	357	}
	358
	359	/* add default label */
3de23255	360	static int __net_init ip6addrlbl_net_init(struct net *net)
2a8cc6c8 YH	361	{
	362	int err = 0;
	363	int i;
	364
f3213831	365	ADDRLABEL(KERN_DEBUG "%s\n", __func__);
2a8cc6c8 YH	366
2a8cc6c8 YH	367	for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
3de23255 BT	368	int ret = ip6addrlbl_add(net,
3de23255 BT	369	ip6addrlbl_init_table[i].prefix,
2a8cc6c8 YH	370	ip6addrlbl_init_table[i].prefixlen,
	371	0,
	372	ip6addrlbl_init_table[i].label, 0);
	373	/* XXX: should we free all rules when we catch an error? */
	374	if (ret && (!err \|\| err != -ENOMEM))
	375	err = ret;
	376	}
	377	return err;
	378	}
	379
3de23255 BT	380	static void __net_exit ip6addrlbl_net_exit(struct net *net)
	381	{
	382	struct ip6addrlbl_entry *p = NULL;
	383	struct hlist_node pos, n;
	384
	385	/* Remove all labels belonging to the exiting net */
	386	spin_lock(&ip6addrlbl_table.lock);
	387	hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
	388	if (net_eq(ip6addrlbl_net(p), net)) {
	389	hlist_del_rcu(&p->list);
	390	ip6addrlbl_put(p);
	391	}
	392	}
	393	spin_unlock(&ip6addrlbl_table.lock);
	394	}
	395
	396	static struct pernet_operations ipv6_addr_label_ops = {
	397	.init = ip6addrlbl_net_init,
	398	.exit = ip6addrlbl_net_exit,
	399	};
	400
2a8cc6c8 YH	401	int __init ipv6_addr_label_init(void)
	402	{
	403	spin_lock_init(&ip6addrlbl_table.lock);
	404
3de23255	405	return register_pernet_subsys(&ipv6_addr_label_ops);
2a8cc6c8 YH	406	}
2a8cc6c8 YH	407
2cc6d2bf NH	408	void ipv6_addr_label_cleanup(void)
	409	{
	410	unregister_pernet_subsys(&ipv6_addr_label_ops);
	411	}
	412
2a8cc6c8 YH	413	static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
	414	[IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
	415	[IFAL_LABEL] = { .len = sizeof(u32), },
	416	};
	417
	418	static int ip6addrlbl_newdel(struct sk_buff skb, struct nlmsghdr nlh,
	419	void *arg)
	420	{
3b1e0a65	421	struct net *net = sock_net(skb->sk);
2a8cc6c8 YH	422	struct ifaddrlblmsg *ifal;
	423	struct nlattr *tb[IFAL_MAX+1];
	424	struct in6_addr *pfx;
	425	u32 label;
	426	int err = 0;
	427
	428	err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
	429	if (err < 0)
	430	return err;
	431
	432	ifal = nlmsg_data(nlh);
	433
	434	if (ifal->ifal_family != AF_INET6 \|\|
	435	ifal->ifal_prefixlen > 128)
	436	return -EINVAL;
	437
2a8cc6c8 YH	438	if (!tb[IFAL_ADDRESS])
	439	return -EINVAL;
	440
	441	pfx = nla_data(tb[IFAL_ADDRESS]);
	442	if (!pfx)
	443	return -EINVAL;
	444
	445	if (!tb[IFAL_LABEL])
	446	return -EINVAL;
	447	label = nla_get_u32(tb[IFAL_LABEL]);
	448	if (label == IPV6_ADDR_LABEL_DEFAULT)
	449	return -EINVAL;
	450
	451	switch(nlh->nlmsg_type) {
	452	case RTM_NEWADDRLABEL:
0771275b FW	453	if (ifal->ifal_index &&
	454	!__dev_get_by_index(net, ifal->ifal_index))
	455	return -EINVAL;
	456
3de23255	457	err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
2a8cc6c8 YH	458	ifal->ifal_index, label,
	459	nlh->nlmsg_flags & NLM_F_REPLACE);
	460	break;
	461	case RTM_DELADDRLABEL:
3de23255	462	err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
2a8cc6c8 YH	463	ifal->ifal_index);
	464	break;
	465	default:
	466	err = -EOPNOTSUPP;
	467	}
	468	return err;
	469	}
	470
a50feda5 ED	471	static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
a50feda5 ED	472	int prefixlen, int ifindex, u32 lseq)
2a8cc6c8 YH	473	{
	474	struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
	475	ifal->ifal_family = AF_INET6;
	476	ifal->ifal_prefixlen = prefixlen;
	477	ifal->ifal_flags = 0;
	478	ifal->ifal_index = ifindex;
	479	ifal->ifal_seq = lseq;
	480	};
	481
	482	static int ip6addrlbl_fill(struct sk_buff *skb,
	483	struct ip6addrlbl_entry *p,
	484	u32 lseq,
15e47304	485	u32 portid, u32 seq, int event,
2a8cc6c8 YH	486	unsigned int flags)
2a8cc6c8 YH	487	{
15e47304	488	struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
2a8cc6c8 YH	489	sizeof(struct ifaddrlblmsg), flags);
	490	if (!nlh)
	491	return -EMSGSIZE;
	492
	493	ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
	494
	495	if (nla_put(skb, IFAL_ADDRESS, 16, &p->prefix) < 0 \|\|
	496	nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
	497	nlmsg_cancel(skb, nlh);
	498	return -EMSGSIZE;
	499	}
	500
	501	return nlmsg_end(skb, nlh);
	502	}
	503
	504	static int ip6addrlbl_dump(struct sk_buff skb, struct netlink_callback cb)
	505	{
3b1e0a65	506	struct net *net = sock_net(skb->sk);
2a8cc6c8 YH	507	struct ip6addrlbl_entry *p;
	508	struct hlist_node *pos;
	509	int idx = 0, s_idx = cb->args[0];
	510	int err;
	511
	512	rcu_read_lock();
	513	hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
3de23255 BT	514	if (idx >= s_idx &&
3de23255 BT	515	net_eq(ip6addrlbl_net(p), net)) {
2a8cc6c8 YH	516	if ((err = ip6addrlbl_fill(skb, p,
2a8cc6c8 YH	517	ip6addrlbl_table.seq,
15e47304	518	NETLINK_CB(cb->skb).portid,
2a8cc6c8 YH	519	cb->nlh->nlmsg_seq,
	520	RTM_NEWADDRLABEL,
	521	NLM_F_MULTI)) <= 0)
	522	break;
	523	}
	524	idx++;
	525	}
	526	rcu_read_unlock();
	527	cb->args[0] = idx;
	528	return skb->len;
	529	}
	530
	531	static inline int ip6addrlbl_msgsize(void)
	532	{
a02cec21	533	return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
2a8cc6c8	534	+ nla_total_size(16) /* IFAL_ADDRESS */
a02cec21	535	+ nla_total_size(4); /* IFAL_LABEL */
2a8cc6c8 YH	536	}
	537
	538	static int ip6addrlbl_get(struct sk_buff in_skb, struct nlmsghdr nlh,
	539	void *arg)
	540	{
3b1e0a65	541	struct net *net = sock_net(in_skb->sk);
2a8cc6c8 YH	542	struct ifaddrlblmsg *ifal;
	543	struct nlattr *tb[IFAL_MAX+1];
	544	struct in6_addr *addr;
	545	u32 lseq;
	546	int err = 0;
	547	struct ip6addrlbl_entry *p;
	548	struct sk_buff *skb;
	549
	550	err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
	551	if (err < 0)
	552	return err;
	553
	554	ifal = nlmsg_data(nlh);
	555
	556	if (ifal->ifal_family != AF_INET6 \|\|
	557	ifal->ifal_prefixlen != 128)
	558	return -EINVAL;
	559
	560	if (ifal->ifal_index &&
3de23255	561	!__dev_get_by_index(net, ifal->ifal_index))
2a8cc6c8 YH	562	return -EINVAL;
	563
	564	if (!tb[IFAL_ADDRESS])
	565	return -EINVAL;
	566
	567	addr = nla_data(tb[IFAL_ADDRESS]);
	568	if (!addr)
	569	return -EINVAL;
	570
	571	rcu_read_lock();
3de23255	572	p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
2a8cc6c8 YH	573	if (p && ip6addrlbl_hold(p))
	574	p = NULL;
	575	lseq = ip6addrlbl_table.seq;
	576	rcu_read_unlock();
	577
	578	if (!p) {
	579	err = -ESRCH;
	580	goto out;
	581	}
	582
	583	if (!(skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL))) {
	584	ip6addrlbl_put(p);
	585	return -ENOBUFS;
	586	}
	587
	588	err = ip6addrlbl_fill(skb, p, lseq,
15e47304	589	NETLINK_CB(in_skb).portid, nlh->nlmsg_seq,
2a8cc6c8 YH	590	RTM_NEWADDRLABEL, 0);
	591
	592	ip6addrlbl_put(p);
	593
	594	if (err < 0) {
	595	WARN_ON(err == -EMSGSIZE);
	596	kfree_skb(skb);
	597	goto out;
	598	}
	599
15e47304	600	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2a8cc6c8 YH	601	out:
	602	return err;
	603	}
	604
	605	void __init ipv6_addr_label_rtnl_register(void)
	606	{
c7ac8679 GR	607	__rtnl_register(PF_INET6, RTM_NEWADDRLABEL, ip6addrlbl_newdel,
	608	NULL, NULL);
	609	__rtnl_register(PF_INET6, RTM_DELADDRLABEL, ip6addrlbl_newdel,
	610	NULL, NULL);
	611	__rtnl_register(PF_INET6, RTM_GETADDRLABEL, ip6addrlbl_get,
	612	ip6addrlbl_dump, NULL);
2a8cc6c8 YH	613	}
2a8cc6c8 YH	614