[net-next-2.6.git] / net / decnet / dn_rules.c


/*
 * DECnet       An implementation of the DECnet protocol suite for the LINUX
 *              operating system.  DECnet is implemented using the  BSD Socket
 *              interface as the means of communication with the user level.
 *
 *              DECnet Routing Forwarding Information Base (Rules)
 *
 * Author:      Steve Whitehouse <SteveW@ACM.org>
 *              Mostly copied from Alexey Kuznetsov's ipv4/fib_rules.c
 *
 *
 * Changes:
 *              Steve Whitehouse <steve@chygwyn.com>
 *              Updated for Thomas Graf's generic rules
 *
 */
#include <linux/net.h>
#include <linux/init.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/netdevice.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <linux/rcupdate.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/fib_rules.h>
#include <net/dn.h>
#include <net/dn_fib.h>
#include <net/dn_neigh.h>
#include <net/dn_dev.h>

static struct fib_rules_ops dn_fib_rules_ops;

struct dn_fib_rule
{
	struct fib_rule		common;
	unsigned char		dst_len;
	unsigned char		src_len;
	__le16			src;
	__le16			srcmask;
	__le16			dst;
	__le16			dstmask;
	__le16			srcmap;
	u8			flags;
};

static struct dn_fib_rule default_rule = {
	.common = {
		.refcnt =		ATOMIC_INIT(2),
		.pref =			0x7fff,
		.table =		RT_TABLE_MAIN,
		.action =		FR_ACT_TO_TBL,
	},
};

static LIST_HEAD(dn_fib_rules);


int dn_fib_lookup(struct flowi *flp, struct dn_fib_res *res)
{
	struct fib_lookup_arg arg = {
		.result = res,
	};
	int err;

	err = fib_rules_lookup(&dn_fib_rules_ops, flp, 0, &arg);
	res->r = arg.rule;

	return err;
}

static int dn_fib_rule_action(struct fib_rule *rule, struct flowi *flp,
			      int flags, struct fib_lookup_arg *arg)
{
	int err = -EAGAIN;
	struct dn_fib_table *tbl;

	switch(rule->action) {
	case FR_ACT_TO_TBL:
		break;

	case FR_ACT_UNREACHABLE:
		err = -ENETUNREACH;
		goto errout;

	case FR_ACT_PROHIBIT:
		err = -EACCES;
		goto errout;

	case FR_ACT_BLACKHOLE:
	default:
		err = -EINVAL;
		goto errout;
	}

	tbl = dn_fib_get_table(rule->table, 0);
	if (tbl == NULL)
		goto errout;

	err = tbl->lookup(tbl, flp, (struct dn_fib_res *)arg->result);
	if (err > 0)
		err = -EAGAIN;
errout:
	return err;
}

static struct nla_policy dn_fib_rule_policy[FRA_MAX+1] __read_mostly = {
	FRA_GENERIC_POLICY,
};

static int dn_fib_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
{
	struct dn_fib_rule *r = (struct dn_fib_rule *)rule;
	__le16 daddr = fl->fld_dst;
	__le16 saddr = fl->fld_src;

	if (((saddr ^ r->src) & r->srcmask) ||
	    ((daddr ^ r->dst) & r->dstmask))
		return 0;

	return 1;
}

static int dn_fib_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
				 struct nlmsghdr *nlh, struct fib_rule_hdr *frh,
				 struct nlattr **tb)
{
	int err = -EINVAL;
	struct dn_fib_rule *r = (struct dn_fib_rule *)rule;

	if (frh->tos)
		goto  errout;

	if (rule->table == RT_TABLE_UNSPEC) {
		if (rule->action == FR_ACT_TO_TBL) {
			struct dn_fib_table *table;

			table = dn_fib_empty_table();
			if (table == NULL) {
				err = -ENOBUFS;
				goto errout;
			}

			rule->table = table->n;
		}
	}

	if (frh->src_len)
		r->src = nla_get_le16(tb[FRA_SRC]);

	if (frh->dst_len)
		r->dst = nla_get_le16(tb[FRA_DST]);

	r->src_len = frh->src_len;
	r->srcmask = dnet_make_mask(r->src_len);
	r->dst_len = frh->dst_len;
	r->dstmask = dnet_make_mask(r->dst_len);
	err = 0;
errout:
	return err;
}

static int dn_fib_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
			       struct nlattr **tb)
{
	struct dn_fib_rule *r = (struct dn_fib_rule *)rule;

	if (frh->src_len && (r->src_len != frh->src_len))
		return 0;

	if (frh->dst_len && (r->dst_len != frh->dst_len))
		return 0;

	if (frh->src_len && (r->src != nla_get_le16(tb[FRA_SRC])))
		return 0;

	if (frh->dst_len && (r->dst != nla_get_le16(tb[FRA_DST])))
		return 0;

	return 1;
}

unsigned dnet_addr_type(__le16 addr)
{
	struct flowi fl = { .nl_u = { .dn_u = { .daddr = addr } } };
	struct dn_fib_res res;
	unsigned ret = RTN_UNICAST;
	struct dn_fib_table *tb = dn_fib_get_table(RT_TABLE_LOCAL, 0);

	res.r = NULL;

	if (tb) {
		if (!tb->lookup(tb, &fl, &res)) {
			ret = res.type;
			dn_fib_res_put(&res);
		}
	}
	return ret;
}

static int dn_fib_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
			    struct nlmsghdr *nlh, struct fib_rule_hdr *frh)
{
	struct dn_fib_rule *r = (struct dn_fib_rule *)rule;

	frh->family = AF_DECnet;
	frh->dst_len = r->dst_len;
	frh->src_len = r->src_len;
	frh->tos = 0;

	if (r->dst_len)
		NLA_PUT_LE16(skb, FRA_DST, r->dst);
	if (r->src_len)
		NLA_PUT_LE16(skb, FRA_SRC, r->src);

	return 0;

nla_put_failure:
	return -ENOBUFS;
}

static u32 dn_fib_rule_default_pref(void)
{
	struct list_head *pos;
	struct fib_rule *rule;

	if (!list_empty(&dn_fib_rules)) {
		pos = dn_fib_rules.next;
		if (pos->next != &dn_fib_rules) {
			rule = list_entry(pos->next, struct fib_rule, list);
			if (rule->pref)
				return rule->pref - 1;
		}
	}

	return 0;
}

static struct fib_rules_ops dn_fib_rules_ops = {
	.family		= AF_DECnet,
	.rule_size	= sizeof(struct dn_fib_rule),
	.addr_size	= sizeof(u16),
	.action		= dn_fib_rule_action,
	.match		= dn_fib_rule_match,
	.configure	= dn_fib_rule_configure,
	.compare	= dn_fib_rule_compare,
	.fill		= dn_fib_rule_fill,
	.default_pref	= dn_fib_rule_default_pref,
	.nlgroup	= RTNLGRP_DECnet_RULE,
	.policy		= dn_fib_rule_policy,
	.rules_list	= &dn_fib_rules,
	.owner		= THIS_MODULE,
};

void __init dn_fib_rules_init(void)
{
	list_add_tail(&default_rule.common.list, &dn_fib_rules);
	fib_rules_register(&dn_fib_rules_ops);
}

void __exit dn_fib_rules_cleanup(void)
{
	fib_rules_unregister(&dn_fib_rules_ops);
}
Commit	Line	Data
	1
	2	/*
	3	* DECnet An implementation of the DECnet protocol suite for the LINUX
	4	* operating system. DECnet is implemented using the BSD Socket
	5	* interface as the means of communication with the user level.
	6	*
	7	* DECnet Routing Forwarding Information Base (Rules)
	8	*
	9	* Author: Steve Whitehouse <SteveW@ACM.org>
	10	* Mostly copied from Alexey Kuznetsov's ipv4/fib_rules.c
	11	*
	12	*
	13	* Changes:
	14	* Steve Whitehouse <steve@chygwyn.com>
	15	* Updated for Thomas Graf's generic rules
	16	*
	17	*/
	18	#include <linux/net.h>
	19	#include <linux/init.h>
	20	#include <linux/netlink.h>
	21	#include <linux/rtnetlink.h>
	22	#include <linux/netdevice.h>
	23	#include <linux/spinlock.h>
	24	#include <linux/list.h>
	25	#include <linux/rcupdate.h>
	26	#include <net/neighbour.h>
	27	#include <net/dst.h>
	28	#include <net/flow.h>
	29	#include <net/fib_rules.h>
	30	#include <net/dn.h>
	31	#include <net/dn_fib.h>
	32	#include <net/dn_neigh.h>
	33	#include <net/dn_dev.h>
	34
	35	static struct fib_rules_ops dn_fib_rules_ops;
	36
	37	struct dn_fib_rule
	38	{
	39	struct fib_rule common;
	40	unsigned char dst_len;
	41	unsigned char src_len;
	42	__le16 src;
	43	__le16 srcmask;
	44	__le16 dst;
	45	__le16 dstmask;
	46	__le16 srcmap;
	47	u8 flags;
	48	};
	49
	50	static struct dn_fib_rule default_rule = {
	51	.common = {
	52	.refcnt = ATOMIC_INIT(2),
	53	.pref = 0x7fff,
	54	.table = RT_TABLE_MAIN,
	55	.action = FR_ACT_TO_TBL,
	56	},
	57	};
	58
	59	static LIST_HEAD(dn_fib_rules);
	60
	61
	62	int dn_fib_lookup(struct flowi flp, struct dn_fib_res res)
	63	{
	64	struct fib_lookup_arg arg = {
	65	.result = res,
	66	};
	67	int err;
	68
	69	err = fib_rules_lookup(&dn_fib_rules_ops, flp, 0, &arg);
	70	res->r = arg.rule;
	71
	72	return err;
	73	}
	74
	75	static int dn_fib_rule_action(struct fib_rule rule, struct flowi flp,
	76	int flags, struct fib_lookup_arg *arg)
	77	{
	78	int err = -EAGAIN;
	79	struct dn_fib_table *tbl;
	80
	81	switch(rule->action) {
	82	case FR_ACT_TO_TBL:
	83	break;
	84
	85	case FR_ACT_UNREACHABLE:
	86	err = -ENETUNREACH;
	87	goto errout;
	88
	89	case FR_ACT_PROHIBIT:
	90	err = -EACCES;
	91	goto errout;
	92
	93	case FR_ACT_BLACKHOLE:
	94	default:
	95	err = -EINVAL;
	96	goto errout;
	97	}
	98
	99	tbl = dn_fib_get_table(rule->table, 0);
	100	if (tbl == NULL)
	101	goto errout;
	102
	103	err = tbl->lookup(tbl, flp, (struct dn_fib_res *)arg->result);
	104	if (err > 0)
	105	err = -EAGAIN;
	106	errout:
	107	return err;
	108	}
	109
	110	static struct nla_policy dn_fib_rule_policy[FRA_MAX+1] __read_mostly = {
	111	FRA_GENERIC_POLICY,
	112	};
	113
	114	static int dn_fib_rule_match(struct fib_rule rule, struct flowi fl, int flags)
	115	{
	116	struct dn_fib_rule r = (struct dn_fib_rule )rule;
	117	__le16 daddr = fl->fld_dst;
	118	__le16 saddr = fl->fld_src;
	119
	120	if (((saddr ^ r->src) & r->srcmask) \|\|
	121	((daddr ^ r->dst) & r->dstmask))
	122	return 0;
	123
	124	return 1;
	125	}
	126
	127	static int dn_fib_rule_configure(struct fib_rule rule, struct sk_buff skb,
	128	struct nlmsghdr nlh, struct fib_rule_hdr frh,
	129	struct nlattr **tb)
	130	{
	131	int err = -EINVAL;
	132	struct dn_fib_rule r = (struct dn_fib_rule )rule;
	133
	134	if (frh->tos)
	135	goto errout;
	136
	137	if (rule->table == RT_TABLE_UNSPEC) {
	138	if (rule->action == FR_ACT_TO_TBL) {
	139	struct dn_fib_table *table;
	140
	141	table = dn_fib_empty_table();
	142	if (table == NULL) {
	143	err = -ENOBUFS;
	144	goto errout;
	145	}
	146
	147	rule->table = table->n;
	148	}
	149	}
	150
	151	if (frh->src_len)
	152	r->src = nla_get_le16(tb[FRA_SRC]);
	153
	154	if (frh->dst_len)
	155	r->dst = nla_get_le16(tb[FRA_DST]);
	156
	157	r->src_len = frh->src_len;
	158	r->srcmask = dnet_make_mask(r->src_len);
	159	r->dst_len = frh->dst_len;
	160	r->dstmask = dnet_make_mask(r->dst_len);
	161	err = 0;
	162	errout:
	163	return err;
	164	}
	165
	166	static int dn_fib_rule_compare(struct fib_rule rule, struct fib_rule_hdr frh,
	167	struct nlattr **tb)
	168	{
	169	struct dn_fib_rule r = (struct dn_fib_rule )rule;
	170
	171	if (frh->src_len && (r->src_len != frh->src_len))
	172	return 0;
	173
	174	if (frh->dst_len && (r->dst_len != frh->dst_len))
	175	return 0;
	176
	177	if (frh->src_len && (r->src != nla_get_le16(tb[FRA_SRC])))
	178	return 0;
	179
	180	if (frh->dst_len && (r->dst != nla_get_le16(tb[FRA_DST])))
	181	return 0;
	182
	183	return 1;
	184	}
	185
	186	unsigned dnet_addr_type(__le16 addr)
	187	{
	188	struct flowi fl = { .nl_u = { .dn_u = { .daddr = addr } } };
	189	struct dn_fib_res res;
	190	unsigned ret = RTN_UNICAST;
	191	struct dn_fib_table *tb = dn_fib_get_table(RT_TABLE_LOCAL, 0);
	192
	193	res.r = NULL;
	194
	195	if (tb) {
	196	if (!tb->lookup(tb, &fl, &res)) {
	197	ret = res.type;
	198	dn_fib_res_put(&res);
	199	}
	200	}
	201	return ret;
	202	}
	203
	204	static int dn_fib_rule_fill(struct fib_rule rule, struct sk_buff skb,
	205	struct nlmsghdr nlh, struct fib_rule_hdr frh)
	206	{
	207	struct dn_fib_rule r = (struct dn_fib_rule )rule;
	208
	209	frh->family = AF_DECnet;
	210	frh->dst_len = r->dst_len;
	211	frh->src_len = r->src_len;
	212	frh->tos = 0;
	213
	214	if (r->dst_len)
	215	NLA_PUT_LE16(skb, FRA_DST, r->dst);
	216	if (r->src_len)
	217	NLA_PUT_LE16(skb, FRA_SRC, r->src);
	218
	219	return 0;
	220
	221	nla_put_failure:
	222	return -ENOBUFS;
	223	}
	224
	225	static u32 dn_fib_rule_default_pref(void)
	226	{
	227	struct list_head *pos;
	228	struct fib_rule *rule;
	229
	230	if (!list_empty(&dn_fib_rules)) {
	231	pos = dn_fib_rules.next;
	232	if (pos->next != &dn_fib_rules) {
	233	rule = list_entry(pos->next, struct fib_rule, list);
	234	if (rule->pref)
	235	return rule->pref - 1;
	236	}
	237	}
	238
	239	return 0;
	240	}
	241
	242	static struct fib_rules_ops dn_fib_rules_ops = {
	243	.family = AF_DECnet,
	244	.rule_size = sizeof(struct dn_fib_rule),
	245	.addr_size = sizeof(u16),
	246	.action = dn_fib_rule_action,
	247	.match = dn_fib_rule_match,
	248	.configure = dn_fib_rule_configure,
	249	.compare = dn_fib_rule_compare,
	250	.fill = dn_fib_rule_fill,
	251	.default_pref = dn_fib_rule_default_pref,
	252	.nlgroup = RTNLGRP_DECnet_RULE,
	253	.policy = dn_fib_rule_policy,
	254	.rules_list = &dn_fib_rules,
	255	.owner = THIS_MODULE,
	256	};
	257
	258	void __init dn_fib_rules_init(void)
	259	{
	260	list_add_tail(&default_rule.common.list, &dn_fib_rules);
	261	fib_rules_register(&dn_fib_rules_ops);
	262	}
	263
	264	void __exit dn_fib_rules_cleanup(void)
	265	{
	266	fib_rules_unregister(&dn_fib_rules_ops);
	267	}
	268
	269