[net-next-2.6.git] / net / core / fib_rules.c

/*
 * net/core/fib_rules.c		Generic Routing Rules
 *
 *	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, version 2.
 *
 * Authors:	Thomas Graf <tgraf@suug.ch>
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <net/fib_rules.h>

static LIST_HEAD(rules_ops);
static DEFINE_SPINLOCK(rules_mod_lock);

static void notify_rule_change(int event, struct fib_rule *rule,
			       struct fib_rules_ops *ops, struct nlmsghdr *nlh,
			       u32 pid);

static struct fib_rules_ops *lookup_rules_ops(int family)
{
	struct fib_rules_ops *ops;

	rcu_read_lock();
	list_for_each_entry_rcu(ops, &rules_ops, list) {
		if (ops->family == family) {
			if (!try_module_get(ops->owner))
				ops = NULL;
			rcu_read_unlock();
			return ops;
		}
	}
	rcu_read_unlock();

	return NULL;
}

static void rules_ops_put(struct fib_rules_ops *ops)
{
	if (ops)
		module_put(ops->owner);
}

int fib_rules_register(struct fib_rules_ops *ops)
{
	int err = -EEXIST;
	struct fib_rules_ops *o;

	if (ops->rule_size < sizeof(struct fib_rule))
		return -EINVAL;

	if (ops->match == NULL || ops->configure == NULL ||
	    ops->compare == NULL || ops->fill == NULL ||
	    ops->action == NULL)
		return -EINVAL;

	spin_lock(&rules_mod_lock);
	list_for_each_entry(o, &rules_ops, list)
		if (ops->family == o->family)
			goto errout;

	list_add_tail_rcu(&ops->list, &rules_ops);
	err = 0;
errout:
	spin_unlock(&rules_mod_lock);

	return err;
}

EXPORT_SYMBOL_GPL(fib_rules_register);

static void cleanup_ops(struct fib_rules_ops *ops)
{
	struct fib_rule *rule, *tmp;

	list_for_each_entry_safe(rule, tmp, ops->rules_list, list) {
		list_del_rcu(&rule->list);
		fib_rule_put(rule);
	}
}

int fib_rules_unregister(struct fib_rules_ops *ops)
{
	int err = 0;
	struct fib_rules_ops *o;

	spin_lock(&rules_mod_lock);
	list_for_each_entry(o, &rules_ops, list) {
		if (o == ops) {
			list_del_rcu(&o->list);
			cleanup_ops(ops);
			goto out;
		}
	}

	err = -ENOENT;
out:
	spin_unlock(&rules_mod_lock);

	synchronize_rcu();

	return err;
}

EXPORT_SYMBOL_GPL(fib_rules_unregister);

int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
		     int flags, struct fib_lookup_arg *arg)
{
	struct fib_rule *rule;
	int err;

	rcu_read_lock();

	list_for_each_entry_rcu(rule, ops->rules_list, list) {
		if (rule->ifindex && (rule->ifindex != fl->iif))
			continue;

		if ((rule->mark ^ fl->mark) & rule->mark_mask)
			continue;

		if (!ops->match(rule, fl, flags))
			continue;

		err = ops->action(rule, fl, flags, arg);
		if (err != -EAGAIN) {
			fib_rule_get(rule);
			arg->rule = rule;
			goto out;
		}
	}

	err = -ENETUNREACH;
out:
	rcu_read_unlock();

	return err;
}

EXPORT_SYMBOL_GPL(fib_rules_lookup);

int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
{
	struct fib_rule_hdr *frh = nlmsg_data(nlh);
	struct fib_rules_ops *ops = NULL;
	struct fib_rule *rule, *r, *last = NULL;
	struct nlattr *tb[FRA_MAX+1];
	int err = -EINVAL;

	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
		goto errout;

	ops = lookup_rules_ops(frh->family);
	if (ops == NULL) {
		err = EAFNOSUPPORT;
		goto errout;
	}

	err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
	if (err < 0)
		goto errout;

	rule = kzalloc(ops->rule_size, GFP_KERNEL);
	if (rule == NULL) {
		err = -ENOMEM;
		goto errout;
	}

	if (tb[FRA_PRIORITY])
		rule->pref = nla_get_u32(tb[FRA_PRIORITY]);

	if (tb[FRA_IFNAME]) {
		struct net_device *dev;

		rule->ifindex = -1;
		nla_strlcpy(rule->ifname, tb[FRA_IFNAME], IFNAMSIZ);
		dev = __dev_get_by_name(rule->ifname);
		if (dev)
			rule->ifindex = dev->ifindex;
	}

	if (tb[FRA_FWMARK]) {
		rule->mark = nla_get_u32(tb[FRA_FWMARK]);
		if (rule->mark)
			/* compatibility: if the mark value is non-zero all bits
			 * are compared unless a mask is explicitly specified.
			 */
			rule->mark_mask = 0xFFFFFFFF;
	}

	if (tb[FRA_FWMASK])
		rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);

	rule->action = frh->action;
	rule->flags = frh->flags;
	rule->table = frh_get_table(frh, tb);

	if (!rule->pref && ops->default_pref)
		rule->pref = ops->default_pref();

	err = ops->configure(rule, skb, nlh, frh, tb);
	if (err < 0)
		goto errout_free;

	list_for_each_entry(r, ops->rules_list, list) {
		if (r->pref > rule->pref)
			break;
		last = r;
	}

	fib_rule_get(rule);

	if (last)
		list_add_rcu(&rule->list, &last->list);
	else
		list_add_rcu(&rule->list, ops->rules_list);

	notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).pid);
	rules_ops_put(ops);
	return 0;

errout_free:
	kfree(rule);
errout:
	rules_ops_put(ops);
	return err;
}

int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
{
	struct fib_rule_hdr *frh = nlmsg_data(nlh);
	struct fib_rules_ops *ops = NULL;
	struct fib_rule *rule;
	struct nlattr *tb[FRA_MAX+1];
	int err = -EINVAL;

	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
		goto errout;

	ops = lookup_rules_ops(frh->family);
	if (ops == NULL) {
		err = EAFNOSUPPORT;
		goto errout;
	}

	err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
	if (err < 0)
		goto errout;

	list_for_each_entry(rule, ops->rules_list, list) {
		if (frh->action && (frh->action != rule->action))
			continue;

		if (frh->table && (frh_get_table(frh, tb) != rule->table))
			continue;

		if (tb[FRA_PRIORITY] &&
		    (rule->pref != nla_get_u32(tb[FRA_PRIORITY])))
			continue;

		if (tb[FRA_IFNAME] &&
		    nla_strcmp(tb[FRA_IFNAME], rule->ifname))
			continue;

		if (tb[FRA_FWMARK] &&
		    (rule->mark != nla_get_u32(tb[FRA_FWMARK])))
			continue;

		if (tb[FRA_FWMASK] &&
		    (rule->mark_mask != nla_get_u32(tb[FRA_FWMASK])))
			continue;

		if (!ops->compare(rule, frh, tb))
			continue;

		if (rule->flags & FIB_RULE_PERMANENT) {
			err = -EPERM;
			goto errout;
		}

		list_del_rcu(&rule->list);
		synchronize_rcu();
		notify_rule_change(RTM_DELRULE, rule, ops, nlh,
				   NETLINK_CB(skb).pid);
		fib_rule_put(rule);
		rules_ops_put(ops);
		return 0;
	}

	err = -ENOENT;
errout:
	rules_ops_put(ops);
	return err;
}

static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
			    u32 pid, u32 seq, int type, int flags,
			    struct fib_rules_ops *ops)
{
	struct nlmsghdr *nlh;
	struct fib_rule_hdr *frh;

	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
	if (nlh == NULL)
		return -1;

	frh = nlmsg_data(nlh);
	frh->table = rule->table;
	NLA_PUT_U32(skb, FRA_TABLE, rule->table);
	frh->res1 = 0;
	frh->res2 = 0;
	frh->action = rule->action;
	frh->flags = rule->flags;

	if (rule->ifname[0])
		NLA_PUT_STRING(skb, FRA_IFNAME, rule->ifname);

	if (rule->pref)
		NLA_PUT_U32(skb, FRA_PRIORITY, rule->pref);

	if (rule->mark)
		NLA_PUT_U32(skb, FRA_FWMARK, rule->mark);

	if (rule->mark_mask || rule->mark)
		NLA_PUT_U32(skb, FRA_FWMASK, rule->mark_mask);

	if (ops->fill(rule, skb, nlh, frh) < 0)
		goto nla_put_failure;

	return nlmsg_end(skb, nlh);

nla_put_failure:
	return nlmsg_cancel(skb, nlh);
}

int fib_rules_dump(struct sk_buff *skb, struct netlink_callback *cb, int family)
{
	int idx = 0;
	struct fib_rule *rule;
	struct fib_rules_ops *ops;

	ops = lookup_rules_ops(family);
	if (ops == NULL)
		return -EAFNOSUPPORT;

	rcu_read_lock();
	list_for_each_entry(rule, ops->rules_list, list) {
		if (idx < cb->args[0])
			goto skip;

		if (fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).pid,
				     cb->nlh->nlmsg_seq, RTM_NEWRULE,
				     NLM_F_MULTI, ops) < 0)
			break;
skip:
		idx++;
	}
	rcu_read_unlock();
	cb->args[0] = idx;
	rules_ops_put(ops);

	return skb->len;
}

EXPORT_SYMBOL_GPL(fib_rules_dump);

static void notify_rule_change(int event, struct fib_rule *rule,
			       struct fib_rules_ops *ops, struct nlmsghdr *nlh,
			       u32 pid)
{
	struct sk_buff *skb;
	int err = -ENOBUFS;

	skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
	if (skb == NULL)
		goto errout;

	err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
	if (err < 0) {
		kfree_skb(skb);
		goto errout;
	}

	err = rtnl_notify(skb, pid, ops->nlgroup, nlh, GFP_KERNEL);
errout:
	if (err < 0)
		rtnl_set_sk_err(ops->nlgroup, err);
}

static void attach_rules(struct list_head *rules, struct net_device *dev)
{
	struct fib_rule *rule;

	list_for_each_entry(rule, rules, list) {
		if (rule->ifindex == -1 &&
		    strcmp(dev->name, rule->ifname) == 0)
			rule->ifindex = dev->ifindex;
	}
}

static void detach_rules(struct list_head *rules, struct net_device *dev)
{
	struct fib_rule *rule;

	list_for_each_entry(rule, rules, list)
		if (rule->ifindex == dev->ifindex)
			rule->ifindex = -1;
}


static int fib_rules_event(struct notifier_block *this, unsigned long event,
			    void *ptr)
{
	struct net_device *dev = ptr;
	struct fib_rules_ops *ops;

	ASSERT_RTNL();
	rcu_read_lock();

	switch (event) {
	case NETDEV_REGISTER:
		list_for_each_entry(ops, &rules_ops, list)
			attach_rules(ops->rules_list, dev);
		break;

	case NETDEV_UNREGISTER:
		list_for_each_entry(ops, &rules_ops, list)
			detach_rules(ops->rules_list, dev);
		break;
	}

	rcu_read_unlock();

	return NOTIFY_DONE;
}

static struct notifier_block fib_rules_notifier = {
	.notifier_call = fib_rules_event,
};

static int __init fib_rules_init(void)
{
	return register_netdevice_notifier(&fib_rules_notifier);
}

subsys_initcall(fib_rules_init);
Commit	Line	Data
14c0b97d TG	1	/*
	2	* net/core/fib_rules.c Generic Routing Rules
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public License as
	6	* published by the Free Software Foundation, version 2.
	7	*
	8	* Authors: Thomas Graf <tgraf@suug.ch>
	9	*/
	10
14c0b97d TG	11	#include <linux/types.h>
	12	#include <linux/kernel.h>
	13	#include <linux/list.h>
	14	#include <net/fib_rules.h>
	15
	16	static LIST_HEAD(rules_ops);
	17	static DEFINE_SPINLOCK(rules_mod_lock);
	18
	19	static void notify_rule_change(int event, struct fib_rule *rule,
c17084d2 TG	20	struct fib_rules_ops ops, struct nlmsghdr nlh,
c17084d2 TG	21	u32 pid);
14c0b97d TG	22
	23	static struct fib_rules_ops *lookup_rules_ops(int family)
	24	{
	25	struct fib_rules_ops *ops;
	26
	27	rcu_read_lock();
	28	list_for_each_entry_rcu(ops, &rules_ops, list) {
	29	if (ops->family == family) {
	30	if (!try_module_get(ops->owner))
	31	ops = NULL;
	32	rcu_read_unlock();
	33	return ops;
	34	}
	35	}
	36	rcu_read_unlock();
	37
	38	return NULL;
	39	}
	40
	41	static void rules_ops_put(struct fib_rules_ops *ops)
	42	{
	43	if (ops)
	44	module_put(ops->owner);
	45	}
	46
	47	int fib_rules_register(struct fib_rules_ops *ops)
	48	{
	49	int err = -EEXIST;
	50	struct fib_rules_ops *o;
	51
	52	if (ops->rule_size < sizeof(struct fib_rule))
	53	return -EINVAL;
	54
	55	if (ops->match == NULL \|\| ops->configure == NULL \|\|
	56	ops->compare == NULL \|\| ops->fill == NULL \|\|
	57	ops->action == NULL)
	58	return -EINVAL;
	59
	60	spin_lock(&rules_mod_lock);
	61	list_for_each_entry(o, &rules_ops, list)
	62	if (ops->family == o->family)
	63	goto errout;
	64
	65	list_add_tail_rcu(&ops->list, &rules_ops);
	66	err = 0;
	67	errout:
	68	spin_unlock(&rules_mod_lock);
	69
	70	return err;
	71	}
	72
	73	EXPORT_SYMBOL_GPL(fib_rules_register);
	74
	75	static void cleanup_ops(struct fib_rules_ops *ops)
	76	{
	77	struct fib_rule rule, tmp;
	78
	79	list_for_each_entry_safe(rule, tmp, ops->rules_list, list) {
	80	list_del_rcu(&rule->list);
	81	fib_rule_put(rule);
	82	}
	83	}
	84
	85	int fib_rules_unregister(struct fib_rules_ops *ops)
86	{
87	int err = 0;
88	struct fib_rules_ops *o;
89
90	spin_lock(&rules_mod_lock);
91	list_for_each_entry(o, &rules_ops, list) {
92	if (o == ops) {
93	list_del_rcu(&o->list);
94	cleanup_ops(ops);
95	goto out;
96	}
97	}
98
99	err = -ENOENT;
100	out:
101	spin_unlock(&rules_mod_lock);
102
103	synchronize_rcu();
104
105	return err;
106	}
107
108	EXPORT_SYMBOL_GPL(fib_rules_unregister);
109
110	int fib_rules_lookup(struct fib_rules_ops ops, struct flowi fl,
111	int flags, struct fib_lookup_arg *arg)
112	{
113	struct fib_rule *rule;
114	int err;
115
116	rcu_read_lock();
117
118	list_for_each_entry_rcu(rule, ops->rules_list, list) {
119	if (rule->ifindex && (rule->ifindex != fl->iif))
120	continue;
121
b8964ed9 TG	122	if ((rule->mark ^ fl->mark) & rule->mark_mask)
	123	continue;
	124
14c0b97d TG	125	if (!ops->match(rule, fl, flags))
	126	continue;
	127
	128	err = ops->action(rule, fl, flags, arg);
	129	if (err != -EAGAIN) {
	130	fib_rule_get(rule);
	131	arg->rule = rule;
	132	goto out;
	133	}
	134	}
	135
	136	err = -ENETUNREACH;
	137	out:
	138	rcu_read_unlock();
	139
	140	return err;
	141	}
	142
	143	EXPORT_SYMBOL_GPL(fib_rules_lookup);
	144
	145	int fib_nl_newrule(struct sk_buff skb, struct nlmsghdr nlh, void *arg)
	146	{
	147	struct fib_rule_hdr *frh = nlmsg_data(nlh);
	148	struct fib_rules_ops *ops = NULL;
	149	struct fib_rule rule, r, *last = NULL;
	150	struct nlattr *tb[FRA_MAX+1];
	151	int err = -EINVAL;
	152
	153	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
	154	goto errout;
	155
	156	ops = lookup_rules_ops(frh->family);
	157	if (ops == NULL) {
	158	err = EAFNOSUPPORT;
	159	goto errout;
	160	}
	161
	162	err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
	163	if (err < 0)
	164	goto errout;
	165
14c0b97d TG	166	rule = kzalloc(ops->rule_size, GFP_KERNEL);
	167	if (rule == NULL) {
	168	err = -ENOMEM;
	169	goto errout;
	170	}
	171
	172	if (tb[FRA_PRIORITY])
	173	rule->pref = nla_get_u32(tb[FRA_PRIORITY]);
	174
	175	if (tb[FRA_IFNAME]) {
	176	struct net_device *dev;
	177
	178	rule->ifindex = -1;
5176f91e	179	nla_strlcpy(rule->ifname, tb[FRA_IFNAME], IFNAMSIZ);
14c0b97d TG	180	dev = __dev_get_by_name(rule->ifname);
	181	if (dev)
	182	rule->ifindex = dev->ifindex;
	183	}
	184
b8964ed9 TG	185	if (tb[FRA_FWMARK]) {
	186	rule->mark = nla_get_u32(tb[FRA_FWMARK]);
	187	if (rule->mark)
	188	/* compatibility: if the mark value is non-zero all bits
	189	* are compared unless a mask is explicitly specified.
	190	*/
	191	rule->mark_mask = 0xFFFFFFFF;
	192	}
	193
	194	if (tb[FRA_FWMASK])
	195	rule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
	196
14c0b97d TG	197	rule->action = frh->action;
14c0b97d TG	198	rule->flags = frh->flags;
9e762a4a	199	rule->table = frh_get_table(frh, tb);
14c0b97d TG	200
	201	if (!rule->pref && ops->default_pref)
	202	rule->pref = ops->default_pref();
	203
	204	err = ops->configure(rule, skb, nlh, frh, tb);
	205	if (err < 0)
	206	goto errout_free;
	207
	208	list_for_each_entry(r, ops->rules_list, list) {
	209	if (r->pref > rule->pref)
	210	break;
	211	last = r;
	212	}
	213
	214	fib_rule_get(rule);
	215
	216	if (last)
	217	list_add_rcu(&rule->list, &last->list);
	218	else
	219	list_add_rcu(&rule->list, ops->rules_list);
	220
c17084d2	221	notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).pid);
14c0b97d TG	222	rules_ops_put(ops);
	223	return 0;
	224
	225	errout_free:
	226	kfree(rule);
	227	errout:
	228	rules_ops_put(ops);
	229	return err;
	230	}
	231
	232	int fib_nl_delrule(struct sk_buff skb, struct nlmsghdr nlh, void *arg)
	233	{
	234	struct fib_rule_hdr *frh = nlmsg_data(nlh);
	235	struct fib_rules_ops *ops = NULL;
	236	struct fib_rule *rule;
	237	struct nlattr *tb[FRA_MAX+1];
	238	int err = -EINVAL;
	239
	240	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
	241	goto errout;
	242
	243	ops = lookup_rules_ops(frh->family);
	244	if (ops == NULL) {
	245	err = EAFNOSUPPORT;
	246	goto errout;
	247	}
	248
	249	err = nlmsg_parse(nlh, sizeof(*frh), tb, FRA_MAX, ops->policy);
	250	if (err < 0)
	251	goto errout;
	252
	253	list_for_each_entry(rule, ops->rules_list, list) {
	254	if (frh->action && (frh->action != rule->action))
	255	continue;
	256
9e762a4a	257	if (frh->table && (frh_get_table(frh, tb) != rule->table))
14c0b97d TG	258	continue;
	259
	260	if (tb[FRA_PRIORITY] &&
	261	(rule->pref != nla_get_u32(tb[FRA_PRIORITY])))
	262	continue;
	263
	264	if (tb[FRA_IFNAME] &&
	265	nla_strcmp(tb[FRA_IFNAME], rule->ifname))
	266	continue;
	267
b8964ed9 TG	268	if (tb[FRA_FWMARK] &&
	269	(rule->mark != nla_get_u32(tb[FRA_FWMARK])))
	270	continue;
	271
	272	if (tb[FRA_FWMASK] &&
	273	(rule->mark_mask != nla_get_u32(tb[FRA_FWMASK])))
	274	continue;
	275
14c0b97d TG	276	if (!ops->compare(rule, frh, tb))
	277	continue;
	278
	279	if (rule->flags & FIB_RULE_PERMANENT) {
	280	err = -EPERM;
	281	goto errout;
	282	}
	283
	284	list_del_rcu(&rule->list);
	285	synchronize_rcu();
c17084d2 TG	286	notify_rule_change(RTM_DELRULE, rule, ops, nlh,
c17084d2 TG	287	NETLINK_CB(skb).pid);
14c0b97d TG	288	fib_rule_put(rule);
	289	rules_ops_put(ops);
	290	return 0;
	291	}
	292
	293	err = -ENOENT;
	294	errout:
	295	rules_ops_put(ops);
	296	return err;
	297	}
	298
	299	static int fib_nl_fill_rule(struct sk_buff skb, struct fib_rule rule,
	300	u32 pid, u32 seq, int type, int flags,
	301	struct fib_rules_ops *ops)
	302	{
	303	struct nlmsghdr *nlh;
	304	struct fib_rule_hdr *frh;
	305
	306	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
	307	if (nlh == NULL)
	308	return -1;
	309
	310	frh = nlmsg_data(nlh);
	311	frh->table = rule->table;
9e762a4a	312	NLA_PUT_U32(skb, FRA_TABLE, rule->table);
14c0b97d TG	313	frh->res1 = 0;
	314	frh->res2 = 0;
	315	frh->action = rule->action;
	316	frh->flags = rule->flags;
	317
	318	if (rule->ifname[0])
	319	NLA_PUT_STRING(skb, FRA_IFNAME, rule->ifname);
	320
	321	if (rule->pref)
	322	NLA_PUT_U32(skb, FRA_PRIORITY, rule->pref);
	323
b8964ed9 TG	324	if (rule->mark)
	325	NLA_PUT_U32(skb, FRA_FWMARK, rule->mark);
	326
	327	if (rule->mark_mask \|\| rule->mark)
	328	NLA_PUT_U32(skb, FRA_FWMASK, rule->mark_mask);
	329
14c0b97d TG	330	if (ops->fill(rule, skb, nlh, frh) < 0)
	331	goto nla_put_failure;
	332
	333	return nlmsg_end(skb, nlh);
	334
	335	nla_put_failure:
	336	return nlmsg_cancel(skb, nlh);
	337	}
	338
	339	int fib_rules_dump(struct sk_buff skb, struct netlink_callback cb, int family)
	340	{
	341	int idx = 0;
	342	struct fib_rule *rule;
	343	struct fib_rules_ops *ops;
	344
	345	ops = lookup_rules_ops(family);
	346	if (ops == NULL)
	347	return -EAFNOSUPPORT;
	348
	349	rcu_read_lock();
	350	list_for_each_entry(rule, ops->rules_list, list) {
	351	if (idx < cb->args[0])
	352	goto skip;
	353
	354	if (fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).pid,
	355	cb->nlh->nlmsg_seq, RTM_NEWRULE,
	356	NLM_F_MULTI, ops) < 0)
	357	break;
	358	skip:
	359	idx++;
	360	}
	361	rcu_read_unlock();
	362	cb->args[0] = idx;
	363	rules_ops_put(ops);
	364
	365	return skb->len;
	366	}
	367
	368	EXPORT_SYMBOL_GPL(fib_rules_dump);
	369
	370	static void notify_rule_change(int event, struct fib_rule *rule,
c17084d2 TG	371	struct fib_rules_ops ops, struct nlmsghdr nlh,
c17084d2 TG	372	u32 pid)
14c0b97d	373	{
c17084d2 TG	374	struct sk_buff *skb;
c17084d2 TG	375	int err = -ENOBUFS;
14c0b97d	376
c17084d2	377	skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
14c0b97d	378	if (skb == NULL)
c17084d2 TG	379	goto errout;
	380
	381	err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
	382	if (err < 0) {
14c0b97d	383	kfree_skb(skb);
c17084d2 TG	384	goto errout;
	385	}
	386
	387	err = rtnl_notify(skb, pid, ops->nlgroup, nlh, GFP_KERNEL);
	388	errout:
	389	if (err < 0)
	390	rtnl_set_sk_err(ops->nlgroup, err);
14c0b97d TG	391	}
	392
	393	static void attach_rules(struct list_head rules, struct net_device dev)
	394	{
	395	struct fib_rule *rule;
	396
	397	list_for_each_entry(rule, rules, list) {
	398	if (rule->ifindex == -1 &&
	399	strcmp(dev->name, rule->ifname) == 0)
	400	rule->ifindex = dev->ifindex;
	401	}
	402	}
	403
	404	static void detach_rules(struct list_head rules, struct net_device dev)
	405	{
	406	struct fib_rule *rule;
	407
	408	list_for_each_entry(rule, rules, list)
	409	if (rule->ifindex == dev->ifindex)
	410	rule->ifindex = -1;
	411	}
	412
	413
	414	static int fib_rules_event(struct notifier_block *this, unsigned long event,
	415	void *ptr)
	416	{
	417	struct net_device *dev = ptr;
	418	struct fib_rules_ops *ops;
	419
	420	ASSERT_RTNL();
	421	rcu_read_lock();
	422
	423	switch (event) {
	424	case NETDEV_REGISTER:
	425	list_for_each_entry(ops, &rules_ops, list)
	426	attach_rules(ops->rules_list, dev);
	427	break;
	428
	429	case NETDEV_UNREGISTER:
	430	list_for_each_entry(ops, &rules_ops, list)
	431	detach_rules(ops->rules_list, dev);
	432	break;
	433	}
	434
	435	rcu_read_unlock();
	436
	437	return NOTIFY_DONE;
	438	}
	439
	440	static struct notifier_block fib_rules_notifier = {
	441	.notifier_call = fib_rules_event,
	442	};
	443
	444	static int __init fib_rules_init(void)
	445	{
	446	return register_netdevice_notifier(&fib_rules_notifier);
	447	}
	448
	449	subsys_initcall(fib_rules_init);