[deliverable/linux.git] / net / decnet / dn_neigh.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 Neighbour Functions (Adjacency Database and
 *                                                        On-Ethernet Cache)
 *
 * Author:      Steve Whitehouse <SteveW@ACM.org>
 *
 *
 * Changes:
 *     Steve Whitehouse     : Fixed router listing routine
 *     Steve Whitehouse     : Added error_report functions
 *     Steve Whitehouse     : Added default router detection
 *     Steve Whitehouse     : Hop counts in outgoing messages
 *     Steve Whitehouse     : Fixed src/dst in outgoing messages so
 *                            forwarding now stands a good chance of
 *                            working.
 *     Steve Whitehouse     : Fixed neighbour states (for now anyway).
 *     Steve Whitehouse     : Made error_report functions dummies. This
 *                            is not the right place to return skbs.
 *     Steve Whitehouse     : Convert to seq_file
 *
 */

#include <linux/net.h>
#include <linux/module.h>
#include <linux/socket.h>
#include <linux/if_arp.h>
#include <linux/slab.h>
#include <linux/if_ether.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <linux/string.h>
#include <linux/netfilter_decnet.h>
#include <linux/spinlock.h>
#include <linux/seq_file.h>
#include <linux/rcupdate.h>
#include <linux/jhash.h>
#include <linux/atomic.h>
#include <net/net_namespace.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/dn.h>
#include <net/dn_dev.h>
#include <net/dn_neigh.h>
#include <net/dn_route.h>

static int dn_neigh_construct(struct neighbour *);
static void dn_neigh_error_report(struct neighbour *, struct sk_buff *);
static int dn_neigh_output(struct neighbour *neigh, struct sk_buff *skb);

/*
 * Operations for adding the link layer header.
 */
static const struct neigh_ops dn_neigh_ops = {
	.family =		AF_DECnet,
	.error_report =		dn_neigh_error_report,
	.output =		dn_neigh_output,
	.connected_output =	dn_neigh_output,
};

static u32 dn_neigh_hash(const void *pkey,
			 const struct net_device *dev,
			 __u32 *hash_rnd)
{
	return jhash_2words(*(__u16 *)pkey, 0, hash_rnd[0]);
}

static bool dn_key_eq(const struct neighbour *neigh, const void *pkey)
{
	return neigh_key_eq16(neigh, pkey);
}

struct neigh_table dn_neigh_table = {
	.family =			PF_DECnet,
	.entry_size =			NEIGH_ENTRY_SIZE(sizeof(struct dn_neigh)),
	.key_len =			sizeof(__le16),
	.protocol =			cpu_to_be16(ETH_P_DNA_RT),
	.hash =				dn_neigh_hash,
	.key_eq =			dn_key_eq,
	.constructor =			dn_neigh_construct,
	.id =				"dn_neigh_cache",
	.parms ={
		.tbl =			&dn_neigh_table,
		.reachable_time =	30 * HZ,
		.data = {
			[NEIGH_VAR_MCAST_PROBES] = 0,
			[NEIGH_VAR_UCAST_PROBES] = 0,
			[NEIGH_VAR_APP_PROBES] = 0,
			[NEIGH_VAR_RETRANS_TIME] = 1 * HZ,
			[NEIGH_VAR_BASE_REACHABLE_TIME] = 30 * HZ,
			[NEIGH_VAR_DELAY_PROBE_TIME] = 5 * HZ,
			[NEIGH_VAR_GC_STALETIME] = 60 * HZ,
			[NEIGH_VAR_QUEUE_LEN_BYTES] = 64*1024,
			[NEIGH_VAR_PROXY_QLEN] = 0,
			[NEIGH_VAR_ANYCAST_DELAY] = 0,
			[NEIGH_VAR_PROXY_DELAY] = 0,
			[NEIGH_VAR_LOCKTIME] = 1 * HZ,
		},
	},
	.gc_interval =			30 * HZ,
	.gc_thresh1 =			128,
	.gc_thresh2 =			512,
	.gc_thresh3 =			1024,
};

static int dn_neigh_construct(struct neighbour *neigh)
{
	struct net_device *dev = neigh->dev;
	struct dn_neigh *dn = (struct dn_neigh *)neigh;
	struct dn_dev *dn_db;
	struct neigh_parms *parms;

	rcu_read_lock();
	dn_db = rcu_dereference(dev->dn_ptr);
	if (dn_db == NULL) {
		rcu_read_unlock();
		return -EINVAL;
	}

	parms = dn_db->neigh_parms;
	if (!parms) {
		rcu_read_unlock();
		return -EINVAL;
	}

	__neigh_parms_put(neigh->parms);
	neigh->parms = neigh_parms_clone(parms);
	rcu_read_unlock();

	neigh->ops = &dn_neigh_ops;
	neigh->nud_state = NUD_NOARP;
	neigh->output = neigh->ops->connected_output;

	if ((dev->type == ARPHRD_IPGRE) || (dev->flags & IFF_POINTOPOINT))
		memcpy(neigh->ha, dev->broadcast, dev->addr_len);
	else if ((dev->type == ARPHRD_ETHER) || (dev->type == ARPHRD_LOOPBACK))
		dn_dn2eth(neigh->ha, dn->addr);
	else {
		net_dbg_ratelimited("Trying to create neigh for hw %d\n",
				    dev->type);
		return -EINVAL;
	}

	/*
	 * Make an estimate of the remote block size by assuming that its
	 * two less then the device mtu, which it true for ethernet (and
	 * other things which support long format headers) since there is
	 * an extra length field (of 16 bits) which isn't part of the
	 * ethernet headers and which the DECnet specs won't admit is part
	 * of the DECnet routing headers either.
	 *
	 * If we over estimate here its no big deal, the NSP negotiations
	 * will prevent us from sending packets which are too large for the
	 * remote node to handle. In any case this figure is normally updated
	 * by a hello message in most cases.
	 */
	dn->blksize = dev->mtu - 2;

	return 0;
}

static void dn_neigh_error_report(struct neighbour *neigh, struct sk_buff *skb)
{
	printk(KERN_DEBUG "dn_neigh_error_report: called\n");
	kfree_skb(skb);
}

static int dn_neigh_output(struct neighbour *neigh, struct sk_buff *skb)
{
	struct dst_entry *dst = skb_dst(skb);
	struct dn_route *rt = (struct dn_route *)dst;
	struct net_device *dev = neigh->dev;
	char mac_addr[ETH_ALEN];
	unsigned int seq;
	int err;

	dn_dn2eth(mac_addr, rt->rt_local_src);
	do {
		seq = read_seqbegin(&neigh->ha_lock);
		err = dev_hard_header(skb, dev, ntohs(skb->protocol),
				      neigh->ha, mac_addr, skb->len);
	} while (read_seqretry(&neigh->ha_lock, seq));

	if (err >= 0)
		err = dev_queue_xmit(skb);
	else {
		kfree_skb(skb);
		err = -EINVAL;
	}
	return err;
}

static int dn_neigh_output_packet(struct sk_buff *skb)
{
	struct dst_entry *dst = skb_dst(skb);
	struct dn_route *rt = (struct dn_route *)dst;
	struct neighbour *neigh = rt->n;

	return neigh->output(neigh, skb);
}

/*
 * For talking to broadcast devices: Ethernet & PPP
 */
static int dn_long_output(struct neighbour *neigh, struct sk_buff *skb)
{
	struct net_device *dev = neigh->dev;
	int headroom = dev->hard_header_len + sizeof(struct dn_long_packet) + 3;
	unsigned char *data;
	struct dn_long_packet *lp;
	struct dn_skb_cb *cb = DN_SKB_CB(skb);


	if (skb_headroom(skb) < headroom) {
		struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
		if (skb2 == NULL) {
			net_crit_ratelimited("dn_long_output: no memory\n");
			kfree_skb(skb);
			return -ENOBUFS;
		}
		consume_skb(skb);
		skb = skb2;
		net_info_ratelimited("dn_long_output: Increasing headroom\n");
	}

	data = skb_push(skb, sizeof(struct dn_long_packet) + 3);
	lp = (struct dn_long_packet *)(data+3);

	*((__le16 *)data) = cpu_to_le16(skb->len - 2);
	*(data + 2) = 1 | DN_RT_F_PF; /* Padding */

	lp->msgflg   = DN_RT_PKT_LONG|(cb->rt_flags&(DN_RT_F_IE|DN_RT_F_RQR|DN_RT_F_RTS));
	lp->d_area   = lp->d_subarea = 0;
	dn_dn2eth(lp->d_id, cb->dst);
	lp->s_area   = lp->s_subarea = 0;
	dn_dn2eth(lp->s_id, cb->src);
	lp->nl2      = 0;
	lp->visit_ct = cb->hops & 0x3f;
	lp->s_class  = 0;
	lp->pt       = 0;

	skb_reset_network_header(skb);

	return NF_HOOK(NFPROTO_DECNET, NF_DN_POST_ROUTING, skb, NULL,
		       neigh->dev, dn_neigh_output_packet);
}

/*
 * For talking to pointopoint and multidrop devices: DDCMP and X.25
 */
static int dn_short_output(struct neighbour *neigh, struct sk_buff *skb)
{
	struct net_device *dev = neigh->dev;
	int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
	struct dn_short_packet *sp;
	unsigned char *data;
	struct dn_skb_cb *cb = DN_SKB_CB(skb);


	if (skb_headroom(skb) < headroom) {
		struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
		if (skb2 == NULL) {
			net_crit_ratelimited("dn_short_output: no memory\n");
			kfree_skb(skb);
			return -ENOBUFS;
		}
		consume_skb(skb);
		skb = skb2;
		net_info_ratelimited("dn_short_output: Increasing headroom\n");
	}

	data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
	*((__le16 *)data) = cpu_to_le16(skb->len - 2);
	sp = (struct dn_short_packet *)(data+2);

	sp->msgflg     = DN_RT_PKT_SHORT|(cb->rt_flags&(DN_RT_F_RQR|DN_RT_F_RTS));
	sp->dstnode    = cb->dst;
	sp->srcnode    = cb->src;
	sp->forward    = cb->hops & 0x3f;

	skb_reset_network_header(skb);

	return NF_HOOK(NFPROTO_DECNET, NF_DN_POST_ROUTING, skb, NULL,
		       neigh->dev, dn_neigh_output_packet);
}

/*
 * For talking to DECnet phase III nodes
 * Phase 3 output is the same as short output, execpt that
 * it clears the area bits before transmission.
 */
static int dn_phase3_output(struct neighbour *neigh, struct sk_buff *skb)
{
	struct net_device *dev = neigh->dev;
	int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
	struct dn_short_packet *sp;
	unsigned char *data;
	struct dn_skb_cb *cb = DN_SKB_CB(skb);

	if (skb_headroom(skb) < headroom) {
		struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
		if (skb2 == NULL) {
			net_crit_ratelimited("dn_phase3_output: no memory\n");
			kfree_skb(skb);
			return -ENOBUFS;
		}
		consume_skb(skb);
		skb = skb2;
		net_info_ratelimited("dn_phase3_output: Increasing headroom\n");
	}

	data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
	*((__le16 *)data) = cpu_to_le16(skb->len - 2);
	sp = (struct dn_short_packet *)(data + 2);

	sp->msgflg   = DN_RT_PKT_SHORT|(cb->rt_flags&(DN_RT_F_RQR|DN_RT_F_RTS));
	sp->dstnode  = cb->dst & cpu_to_le16(0x03ff);
	sp->srcnode  = cb->src & cpu_to_le16(0x03ff);
	sp->forward  = cb->hops & 0x3f;

	skb_reset_network_header(skb);

	return NF_HOOK(NFPROTO_DECNET, NF_DN_POST_ROUTING, skb, NULL,
		       neigh->dev, dn_neigh_output_packet);
}

int dn_to_neigh_output(struct sk_buff *skb)
{
	struct dst_entry *dst = skb_dst(skb);
	struct dn_route *rt = (struct dn_route *) dst;
	struct neighbour *neigh = rt->n;
	struct dn_neigh *dn = (struct dn_neigh *)neigh;
	struct dn_dev *dn_db;
	bool use_long;

	rcu_read_lock();
	dn_db = rcu_dereference(neigh->dev->dn_ptr);
	if (dn_db == NULL) {
		rcu_read_unlock();
		return -EINVAL;
	}
	use_long = dn_db->use_long;
	rcu_read_unlock();

	if (dn->flags & DN_NDFLAG_P3)
		return dn_phase3_output(neigh, skb);
	if (use_long)
		return dn_long_output(neigh, skb);
	else
		return dn_short_output(neigh, skb);
}

/*
 * Unfortunately, the neighbour code uses the device in its hash
 * function, so we don't get any advantage from it. This function
 * basically does a neigh_lookup(), but without comparing the device
 * field. This is required for the On-Ethernet cache
 */

/*
 * Pointopoint link receives a hello message
 */
void dn_neigh_pointopoint_hello(struct sk_buff *skb)
{
	kfree_skb(skb);
}

/*
 * Ethernet router hello message received
 */
int dn_neigh_router_hello(struct sk_buff *skb)
{
	struct rtnode_hello_message *msg = (struct rtnode_hello_message *)skb->data;

	struct neighbour *neigh;
	struct dn_neigh *dn;
	struct dn_dev *dn_db;
	__le16 src;

	src = dn_eth2dn(msg->id);

	neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);

	dn = (struct dn_neigh *)neigh;

	if (neigh) {
		write_lock(&neigh->lock);

		neigh->used = jiffies;
		dn_db = rcu_dereference(neigh->dev->dn_ptr);

		if (!(neigh->nud_state & NUD_PERMANENT)) {
			neigh->updated = jiffies;

			if (neigh->dev->type == ARPHRD_ETHER)
				memcpy(neigh->ha, &eth_hdr(skb)->h_source, ETH_ALEN);

			dn->blksize  = le16_to_cpu(msg->blksize);
			dn->priority = msg->priority;

			dn->flags &= ~DN_NDFLAG_P3;

			switch (msg->iinfo & DN_RT_INFO_TYPE) {
			case DN_RT_INFO_L1RT:
				dn->flags &=~DN_NDFLAG_R2;
				dn->flags |= DN_NDFLAG_R1;
				break;
			case DN_RT_INFO_L2RT:
				dn->flags |= DN_NDFLAG_R2;
			}
		}

		/* Only use routers in our area */
		if ((le16_to_cpu(src)>>10) == (le16_to_cpu((decnet_address))>>10)) {
			if (!dn_db->router) {
				dn_db->router = neigh_clone(neigh);
			} else {
				if (msg->priority > ((struct dn_neigh *)dn_db->router)->priority)
					neigh_release(xchg(&dn_db->router, neigh_clone(neigh)));
			}
		}
		write_unlock(&neigh->lock);
		neigh_release(neigh);
	}

	kfree_skb(skb);
	return 0;
}

/*
 * Endnode hello message received
 */
int dn_neigh_endnode_hello(struct sk_buff *skb)
{
	struct endnode_hello_message *msg = (struct endnode_hello_message *)skb->data;
	struct neighbour *neigh;
	struct dn_neigh *dn;
	__le16 src;

	src = dn_eth2dn(msg->id);

	neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);

	dn = (struct dn_neigh *)neigh;

	if (neigh) {
		write_lock(&neigh->lock);

		neigh->used = jiffies;

		if (!(neigh->nud_state & NUD_PERMANENT)) {
			neigh->updated = jiffies;

			if (neigh->dev->type == ARPHRD_ETHER)
				memcpy(neigh->ha, &eth_hdr(skb)->h_source, ETH_ALEN);
			dn->flags   &= ~(DN_NDFLAG_R1 | DN_NDFLAG_R2);
			dn->blksize  = le16_to_cpu(msg->blksize);
			dn->priority = 0;
		}

		write_unlock(&neigh->lock);
		neigh_release(neigh);
	}

	kfree_skb(skb);
	return 0;
}

static char *dn_find_slot(char *base, int max, int priority)
{
	int i;
	unsigned char *min = NULL;

	base += 6; /* skip first id */

	for(i = 0; i < max; i++) {
		if (!min || (*base < *min))
			min = base;
		base += 7; /* find next priority */
	}

	if (!min)
		return NULL;

	return (*min < priority) ? (min - 6) : NULL;
}

struct elist_cb_state {
	struct net_device *dev;
	unsigned char *ptr;
	unsigned char *rs;
	int t, n;
};

static void neigh_elist_cb(struct neighbour *neigh, void *_info)
{
	struct elist_cb_state *s = _info;
	struct dn_neigh *dn;

	if (neigh->dev != s->dev)
		return;

	dn = (struct dn_neigh *) neigh;
	if (!(dn->flags & (DN_NDFLAG_R1|DN_NDFLAG_R2)))
		return;

	if (s->t == s->n)
		s->rs = dn_find_slot(s->ptr, s->n, dn->priority);
	else
		s->t++;
	if (s->rs == NULL)
		return;

	dn_dn2eth(s->rs, dn->addr);
	s->rs += 6;
	*(s->rs) = neigh->nud_state & NUD_CONNECTED ? 0x80 : 0x0;
	*(s->rs) |= dn->priority;
	s->rs++;
}

int dn_neigh_elist(struct net_device *dev, unsigned char *ptr, int n)
{
	struct elist_cb_state state;

	state.dev = dev;
	state.t = 0;
	state.n = n;
	state.ptr = ptr;
	state.rs = ptr;

	neigh_for_each(&dn_neigh_table, neigh_elist_cb, &state);

	return state.t;
}


#ifdef CONFIG_PROC_FS

static inline void dn_neigh_format_entry(struct seq_file *seq,
					 struct neighbour *n)
{
	struct dn_neigh *dn = (struct dn_neigh *) n;
	char buf[DN_ASCBUF_LEN];

	read_lock(&n->lock);
	seq_printf(seq, "%-7s %s%s%s   %02x    %02d  %07ld %-8s\n",
		   dn_addr2asc(le16_to_cpu(dn->addr), buf),
		   (dn->flags&DN_NDFLAG_R1) ? "1" : "-",
		   (dn->flags&DN_NDFLAG_R2) ? "2" : "-",
		   (dn->flags&DN_NDFLAG_P3) ? "3" : "-",
		   dn->n.nud_state,
		   atomic_read(&dn->n.refcnt),
		   dn->blksize,
		   (dn->n.dev) ? dn->n.dev->name : "?");
	read_unlock(&n->lock);
}

static int dn_neigh_seq_show(struct seq_file *seq, void *v)
{
	if (v == SEQ_START_TOKEN) {
		seq_puts(seq, "Addr    Flags State Use Blksize Dev\n");
	} else {
		dn_neigh_format_entry(seq, v);
	}

	return 0;
}

static void *dn_neigh_seq_start(struct seq_file *seq, loff_t *pos)
{
	return neigh_seq_start(seq, pos, &dn_neigh_table,
			       NEIGH_SEQ_NEIGH_ONLY);
}

static const struct seq_operations dn_neigh_seq_ops = {
	.start = dn_neigh_seq_start,
	.next  = neigh_seq_next,
	.stop  = neigh_seq_stop,
	.show  = dn_neigh_seq_show,
};

static int dn_neigh_seq_open(struct inode *inode, struct file *file)
{
	return seq_open_net(inode, file, &dn_neigh_seq_ops,
			    sizeof(struct neigh_seq_state));
}

static const struct file_operations dn_neigh_seq_fops = {
	.owner		= THIS_MODULE,
	.open		= dn_neigh_seq_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release_net,
};

#endif

void __init dn_neigh_init(void)
{
	neigh_table_init(NEIGH_DN_TABLE, &dn_neigh_table);
	proc_create("decnet_neigh", S_IRUGO, init_net.proc_net,
		    &dn_neigh_seq_fops);
}

void __exit dn_neigh_cleanup(void)
{
	remove_proc_entry("decnet_neigh", init_net.proc_net);
	neigh_table_clear(NEIGH_DN_TABLE, &dn_neigh_table);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* DECnet An implementation of the DECnet protocol suite for the LINUX
	3	* operating system. DECnet is implemented using the BSD Socket
	4	* interface as the means of communication with the user level.
	5	*
429eb0fa	6	* DECnet Neighbour Functions (Adjacency Database and
1da177e4 LT	7	* On-Ethernet Cache)
	8	*
	9	* Author: Steve Whitehouse <SteveW@ACM.org>
	10	*
	11	*
	12	* Changes:
	13	* Steve Whitehouse : Fixed router listing routine
	14	* Steve Whitehouse : Added error_report functions
	15	* Steve Whitehouse : Added default router detection
	16	* Steve Whitehouse : Hop counts in outgoing messages
	17	* Steve Whitehouse : Fixed src/dst in outgoing messages so
	18	* forwarding now stands a good chance of
	19	* working.
	20	* Steve Whitehouse : Fixed neighbour states (for now anyway).
	21	* Steve Whitehouse : Made error_report functions dummies. This
	22	* is not the right place to return skbs.
	23	* Steve Whitehouse : Convert to seq_file
	24	*
	25	*/
	26
1da177e4 LT	27	#include <linux/net.h>
	28	#include <linux/module.h>
	29	#include <linux/socket.h>
	30	#include <linux/if_arp.h>
5a0e3ad6	31	#include <linux/slab.h>
1da177e4 LT	32	#include <linux/if_ether.h>
	33	#include <linux/init.h>
	34	#include <linux/proc_fs.h>
	35	#include <linux/string.h>
	36	#include <linux/netfilter_decnet.h>
	37	#include <linux/spinlock.h>
	38	#include <linux/seq_file.h>
	39	#include <linux/rcupdate.h>
	40	#include <linux/jhash.h>
60063497	41	#include <linux/atomic.h>
457c4cbc	42	#include <net/net_namespace.h>
1da177e4 LT	43	#include <net/neighbour.h>
	44	#include <net/dst.h>
	45	#include <net/flow.h>
	46	#include <net/dn.h>
	47	#include <net/dn_dev.h>
	48	#include <net/dn_neigh.h>
	49	#include <net/dn_route.h>
	50
1da177e4	51	static int dn_neigh_construct(struct neighbour *);
aaa4e704 EB	52	static void dn_neigh_error_report(struct neighbour , struct sk_buff );
aaa4e704 EB	53	static int dn_neigh_output(struct neighbour neigh, struct sk_buff skb);
1da177e4 LT	54
1da177e4 LT	55	/*
aaa4e704	56	* Operations for adding the link layer header.
1da177e4	57	*/
aaa4e704	58	static const struct neigh_ops dn_neigh_ops = {
1da177e4	59	.family = AF_DECnet,
aaa4e704 EB	60	.error_report = dn_neigh_error_report,
	61	.output = dn_neigh_output,
	62	.connected_output = dn_neigh_output,
1da177e4 LT	63	};
1da177e4 LT	64
d6bf7817 ED	65	static u32 dn_neigh_hash(const void *pkey,
d6bf7817 ED	66	const struct net_device *dev,
2c2aba6c	67	__u32 *hash_rnd)
d6bf7817	68	{
2c2aba6c	69	return jhash_2words((__u16 )pkey, 0, hash_rnd[0]);
d6bf7817 ED	70	}
d6bf7817 ED	71
60395a20 EB	72	static bool dn_key_eq(const struct neighbour neigh, const void pkey)
	73	{
	74	return neigh_key_eq16(neigh, pkey);
	75	}
	76
1da177e4 LT	77	struct neigh_table dn_neigh_table = {
1da177e4 LT	78	.family = PF_DECnet,
daaba4fa	79	.entry_size = NEIGH_ENTRY_SIZE(sizeof(struct dn_neigh)),
c4ea94ab	80	.key_len = sizeof(__le16),
bdf53c58	81	.protocol = cpu_to_be16(ETH_P_DNA_RT),
1da177e4	82	.hash = dn_neigh_hash,
60395a20	83	.key_eq = dn_key_eq,
1da177e4 LT	84	.constructor = dn_neigh_construct,
	85	.id = "dn_neigh_cache",
	86	.parms ={
	87	.tbl = &dn_neigh_table,
1f9248e5 JP	88	.reachable_time = 30 * HZ,
	89	.data = {
	90	[NEIGH_VAR_MCAST_PROBES] = 0,
	91	[NEIGH_VAR_UCAST_PROBES] = 0,
	92	[NEIGH_VAR_APP_PROBES] = 0,
	93	[NEIGH_VAR_RETRANS_TIME] = 1 * HZ,
	94	[NEIGH_VAR_BASE_REACHABLE_TIME] = 30 * HZ,
	95	[NEIGH_VAR_DELAY_PROBE_TIME] = 5 * HZ,
	96	[NEIGH_VAR_GC_STALETIME] = 60 * HZ,
	97	[NEIGH_VAR_QUEUE_LEN_BYTES] = 64*1024,
	98	[NEIGH_VAR_PROXY_QLEN] = 0,
	99	[NEIGH_VAR_ANYCAST_DELAY] = 0,
	100	[NEIGH_VAR_PROXY_DELAY] = 0,
	101	[NEIGH_VAR_LOCKTIME] = 1 * HZ,
	102	},
1da177e4 LT	103	},
	104	.gc_interval = 30 * HZ,
	105	.gc_thresh1 = 128,
	106	.gc_thresh2 = 512,
	107	.gc_thresh3 = 1024,
	108	};
	109
1da177e4 LT	110	static int dn_neigh_construct(struct neighbour *neigh)
	111	{
	112	struct net_device *dev = neigh->dev;
	113	struct dn_neigh dn = (struct dn_neigh )neigh;
	114	struct dn_dev *dn_db;
	115	struct neigh_parms *parms;
	116
	117	rcu_read_lock();
	118	dn_db = rcu_dereference(dev->dn_ptr);
	119	if (dn_db == NULL) {
	120	rcu_read_unlock();
	121	return -EINVAL;
	122	}
	123
	124	parms = dn_db->neigh_parms;
	125	if (!parms) {
	126	rcu_read_unlock();
	127	return -EINVAL;
	128	}
	129
	130	__neigh_parms_put(neigh->parms);
	131	neigh->parms = neigh_parms_clone(parms);
1f07247d	132	rcu_read_unlock();
1da177e4	133
aaa4e704	134	neigh->ops = &dn_neigh_ops;
1da177e4 LT	135	neigh->nud_state = NUD_NOARP;
	136	neigh->output = neigh->ops->connected_output;
	137
	138	if ((dev->type == ARPHRD_IPGRE) \|\| (dev->flags & IFF_POINTOPOINT))
	139	memcpy(neigh->ha, dev->broadcast, dev->addr_len);
	140	else if ((dev->type == ARPHRD_ETHER) \|\| (dev->type == ARPHRD_LOOPBACK))
	141	dn_dn2eth(neigh->ha, dn->addr);
	142	else {
e87cc472 JP	143	net_dbg_ratelimited("Trying to create neigh for hw %d\n",
e87cc472 JP	144	dev->type);
1da177e4 LT	145	return -EINVAL;
	146	}
	147
	148	/*
	149	* Make an estimate of the remote block size by assuming that its
	150	* two less then the device mtu, which it true for ethernet (and
	151	* other things which support long format headers) since there is
	152	* an extra length field (of 16 bits) which isn't part of the
	153	* ethernet headers and which the DECnet specs won't admit is part
	154	* of the DECnet routing headers either.
	155	*
	156	* If we over estimate here its no big deal, the NSP negotiations
	157	* will prevent us from sending packets which are too large for the
	158	* remote node to handle. In any case this figure is normally updated
	159	* by a hello message in most cases.
	160	*/
	161	dn->blksize = dev->mtu - 2;
	162
	163	return 0;
	164	}
	165
aaa4e704	166	static void dn_neigh_error_report(struct neighbour neigh, struct sk_buff skb)
1da177e4	167	{
aaa4e704	168	printk(KERN_DEBUG "dn_neigh_error_report: called\n");
1da177e4 LT	169	kfree_skb(skb);
	170	}
	171
aaa4e704	172	static int dn_neigh_output(struct neighbour neigh, struct sk_buff skb)
1da177e4	173	{
adf30907	174	struct dst_entry *dst = skb_dst(skb);
1da177e4	175	struct dn_route rt = (struct dn_route )dst;
1da177e4 LT	176	struct net_device *dev = neigh->dev;
1da177e4 LT	177	char mac_addr[ETH_ALEN];
3329bdfc DM	178	unsigned int seq;
3329bdfc DM	179	int err;
1da177e4 LT	180
1da177e4 LT	181	dn_dn2eth(mac_addr, rt->rt_local_src);
3329bdfc DM	182	do {
	183	seq = read_seqbegin(&neigh->ha_lock);
	184	err = dev_hard_header(skb, dev, ntohs(skb->protocol),
	185	neigh->ha, mac_addr, skb->len);
	186	} while (read_seqretry(&neigh->ha_lock, seq));
	187
	188	if (err >= 0)
	189	err = dev_queue_xmit(skb);
	190	else {
	191	kfree_skb(skb);
	192	err = -EINVAL;
	193	}
	194	return err;
1da177e4 LT	195	}
1da177e4 LT	196
aaa4e704 EB	197	static int dn_neigh_output_packet(struct sk_buff *skb)
	198	{
	199	struct dst_entry *dst = skb_dst(skb);
	200	struct dn_route rt = (struct dn_route )dst;
	201	struct neighbour *neigh = rt->n;
	202
	203	return neigh->output(neigh, skb);
	204	}
	205
	206	/*
	207	* For talking to broadcast devices: Ethernet & PPP
	208	*/
8f40b161	209	static int dn_long_output(struct neighbour neigh, struct sk_buff skb)
1da177e4	210	{
1da177e4 LT	211	struct net_device *dev = neigh->dev;
	212	int headroom = dev->hard_header_len + sizeof(struct dn_long_packet) + 3;
	213	unsigned char *data;
	214	struct dn_long_packet *lp;
	215	struct dn_skb_cb *cb = DN_SKB_CB(skb);
	216
	217
	218	if (skb_headroom(skb) < headroom) {
	219	struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
	220	if (skb2 == NULL) {
e87cc472	221	net_crit_ratelimited("dn_long_output: no memory\n");
1da177e4 LT	222	kfree_skb(skb);
	223	return -ENOBUFS;
	224	}
5d0ba55b	225	consume_skb(skb);
1da177e4	226	skb = skb2;
e87cc472	227	net_info_ratelimited("dn_long_output: Increasing headroom\n");
1da177e4 LT	228	}
	229
	230	data = skb_push(skb, sizeof(struct dn_long_packet) + 3);
	231	lp = (struct dn_long_packet *)(data+3);
	232
c4106aa8	233	((__le16 )data) = cpu_to_le16(skb->len - 2);
1da177e4 LT	234	(data + 2) = 1 \| DN_RT_F_PF; / Padding */
	235
	236	lp->msgflg = DN_RT_PKT_LONG\|(cb->rt_flags&(DN_RT_F_IE\|DN_RT_F_RQR\|DN_RT_F_RTS));
	237	lp->d_area = lp->d_subarea = 0;
c4ea94ab	238	dn_dn2eth(lp->d_id, cb->dst);
1da177e4	239	lp->s_area = lp->s_subarea = 0;
c4ea94ab	240	dn_dn2eth(lp->s_id, cb->src);
1da177e4 LT	241	lp->nl2 = 0;
	242	lp->visit_ct = cb->hops & 0x3f;
	243	lp->s_class = 0;
	244	lp->pt = 0;
	245
c1d2bbe1	246	skb_reset_network_header(skb);
1da177e4	247
5d877d87 JE	248	return NF_HOOK(NFPROTO_DECNET, NF_DN_POST_ROUTING, skb, NULL,
5d877d87 JE	249	neigh->dev, dn_neigh_output_packet);
1da177e4 LT	250	}
1da177e4 LT	251
aaa4e704 EB	252	/*
	253	* For talking to pointopoint and multidrop devices: DDCMP and X.25
	254	*/
8f40b161	255	static int dn_short_output(struct neighbour neigh, struct sk_buff skb)
1da177e4	256	{
1da177e4 LT	257	struct net_device *dev = neigh->dev;
	258	int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
	259	struct dn_short_packet *sp;
	260	unsigned char *data;
	261	struct dn_skb_cb *cb = DN_SKB_CB(skb);
	262
	263
429eb0fa YH	264	if (skb_headroom(skb) < headroom) {
	265	struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
	266	if (skb2 == NULL) {
e87cc472	267	net_crit_ratelimited("dn_short_output: no memory\n");
429eb0fa YH	268	kfree_skb(skb);
	269	return -ENOBUFS;
	270	}
5d0ba55b	271	consume_skb(skb);
429eb0fa	272	skb = skb2;
e87cc472	273	net_info_ratelimited("dn_short_output: Increasing headroom\n");
429eb0fa	274	}
1da177e4 LT	275
1da177e4 LT	276	data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
c4106aa8	277	((__le16 )data) = cpu_to_le16(skb->len - 2);
1da177e4 LT	278	sp = (struct dn_short_packet *)(data+2);
	279
	280	sp->msgflg = DN_RT_PKT_SHORT\|(cb->rt_flags&(DN_RT_F_RQR\|DN_RT_F_RTS));
	281	sp->dstnode = cb->dst;
	282	sp->srcnode = cb->src;
	283	sp->forward = cb->hops & 0x3f;
	284
c1d2bbe1	285	skb_reset_network_header(skb);
1da177e4	286
5d877d87 JE	287	return NF_HOOK(NFPROTO_DECNET, NF_DN_POST_ROUTING, skb, NULL,
5d877d87 JE	288	neigh->dev, dn_neigh_output_packet);
1da177e4 LT	289	}
	290
	291	/*
aaa4e704 EB	292	* For talking to DECnet phase III nodes
aaa4e704 EB	293	* Phase 3 output is the same as short output, execpt that
1da177e4 LT	294	* it clears the area bits before transmission.
1da177e4 LT	295	*/
8f40b161	296	static int dn_phase3_output(struct neighbour neigh, struct sk_buff skb)
1da177e4	297	{
1da177e4 LT	298	struct net_device *dev = neigh->dev;
	299	int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
	300	struct dn_short_packet *sp;
	301	unsigned char *data;
	302	struct dn_skb_cb *cb = DN_SKB_CB(skb);
	303
	304	if (skb_headroom(skb) < headroom) {
	305	struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
	306	if (skb2 == NULL) {
e87cc472	307	net_crit_ratelimited("dn_phase3_output: no memory\n");
1da177e4 LT	308	kfree_skb(skb);
	309	return -ENOBUFS;
	310	}
5d0ba55b	311	consume_skb(skb);
1da177e4	312	skb = skb2;
e87cc472	313	net_info_ratelimited("dn_phase3_output: Increasing headroom\n");
1da177e4 LT	314	}
	315
	316	data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
c4106aa8	317	((__le16 )data) = cpu_to_le16(skb->len - 2);
1da177e4 LT	318	sp = (struct dn_short_packet *)(data + 2);
	319
	320	sp->msgflg = DN_RT_PKT_SHORT\|(cb->rt_flags&(DN_RT_F_RQR\|DN_RT_F_RTS));
c4106aa8 HH	321	sp->dstnode = cb->dst & cpu_to_le16(0x03ff);
c4106aa8 HH	322	sp->srcnode = cb->src & cpu_to_le16(0x03ff);
1da177e4 LT	323	sp->forward = cb->hops & 0x3f;
1da177e4 LT	324
c1d2bbe1	325	skb_reset_network_header(skb);
1da177e4	326
5d877d87 JE	327	return NF_HOOK(NFPROTO_DECNET, NF_DN_POST_ROUTING, skb, NULL,
5d877d87 JE	328	neigh->dev, dn_neigh_output_packet);
1da177e4 LT	329	}
1da177e4 LT	330
aaa4e704 EB	331	int dn_to_neigh_output(struct sk_buff *skb)
	332	{
	333	struct dst_entry *dst = skb_dst(skb);
	334	struct dn_route rt = (struct dn_route ) dst;
	335	struct neighbour *neigh = rt->n;
	336	struct dn_neigh dn = (struct dn_neigh )neigh;
	337	struct dn_dev *dn_db;
	338	bool use_long;
	339
	340	rcu_read_lock();
	341	dn_db = rcu_dereference(neigh->dev->dn_ptr);
	342	if (dn_db == NULL) {
	343	rcu_read_unlock();
	344	return -EINVAL;
	345	}
	346	use_long = dn_db->use_long;
	347	rcu_read_unlock();
	348
	349	if (dn->flags & DN_NDFLAG_P3)
	350	return dn_phase3_output(neigh, skb);
	351	if (use_long)
	352	return dn_long_output(neigh, skb);
	353	else
	354	return dn_short_output(neigh, skb);
	355	}
	356
1da177e4 LT	357	/*
	358	* Unfortunately, the neighbour code uses the device in its hash
	359	* function, so we don't get any advantage from it. This function
	360	* basically does a neigh_lookup(), but without comparing the device
	361	* field. This is required for the On-Ethernet cache
	362	*/
	363
	364	/*
	365	* Pointopoint link receives a hello message
	366	*/
	367	void dn_neigh_pointopoint_hello(struct sk_buff *skb)
	368	{
	369	kfree_skb(skb);
	370	}
	371
	372	/*
	373	* Ethernet router hello message received
	374	*/
	375	int dn_neigh_router_hello(struct sk_buff *skb)
	376	{
	377	struct rtnode_hello_message msg = (struct rtnode_hello_message )skb->data;
	378
	379	struct neighbour *neigh;
	380	struct dn_neigh *dn;
	381	struct dn_dev *dn_db;
c4ea94ab	382	__le16 src;
1da177e4	383
c4ea94ab	384	src = dn_eth2dn(msg->id);
1da177e4 LT	385
	386	neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);
	387
	388	dn = (struct dn_neigh *)neigh;
	389
	390	if (neigh) {
	391	write_lock(&neigh->lock);
	392
	393	neigh->used = jiffies;
fc766e4c	394	dn_db = rcu_dereference(neigh->dev->dn_ptr);
1da177e4 LT	395
	396	if (!(neigh->nud_state & NUD_PERMANENT)) {
	397	neigh->updated = jiffies;
	398
	399	if (neigh->dev->type == ARPHRD_ETHER)
	400	memcpy(neigh->ha, &eth_hdr(skb)->h_source, ETH_ALEN);
	401
c4106aa8	402	dn->blksize = le16_to_cpu(msg->blksize);
1da177e4 LT	403	dn->priority = msg->priority;
	404
	405	dn->flags &= ~DN_NDFLAG_P3;
	406
06f8fe11 JP	407	switch (msg->iinfo & DN_RT_INFO_TYPE) {
	408	case DN_RT_INFO_L1RT:
	409	dn->flags &=~DN_NDFLAG_R2;
	410	dn->flags \|= DN_NDFLAG_R1;
	411	break;
	412	case DN_RT_INFO_L2RT:
	413	dn->flags \|= DN_NDFLAG_R2;
1da177e4 LT	414	}
	415	}
	416
5062430c	417	/* Only use routers in our area */
c4106aa8	418	if ((le16_to_cpu(src)>>10) == (le16_to_cpu((decnet_address))>>10)) {
5062430c PC	419	if (!dn_db->router) {
	420	dn_db->router = neigh_clone(neigh);
	421	} else {
	422	if (msg->priority > ((struct dn_neigh *)dn_db->router)->priority)
	423	neigh_release(xchg(&dn_db->router, neigh_clone(neigh)));
	424	}
1da177e4 LT	425	}
	426	write_unlock(&neigh->lock);
	427	neigh_release(neigh);
	428	}
	429
	430	kfree_skb(skb);
	431	return 0;
	432	}
	433
	434	/*
	435	* Endnode hello message received
	436	*/
	437	int dn_neigh_endnode_hello(struct sk_buff *skb)
	438	{
	439	struct endnode_hello_message msg = (struct endnode_hello_message )skb->data;
	440	struct neighbour *neigh;
	441	struct dn_neigh *dn;
c4ea94ab	442	__le16 src;
1da177e4	443
c4ea94ab	444	src = dn_eth2dn(msg->id);
1da177e4 LT	445
	446	neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);
	447
	448	dn = (struct dn_neigh *)neigh;
	449
	450	if (neigh) {
	451	write_lock(&neigh->lock);
	452
	453	neigh->used = jiffies;
	454
	455	if (!(neigh->nud_state & NUD_PERMANENT)) {
	456	neigh->updated = jiffies;
	457
	458	if (neigh->dev->type == ARPHRD_ETHER)
	459	memcpy(neigh->ha, &eth_hdr(skb)->h_source, ETH_ALEN);
	460	dn->flags &= ~(DN_NDFLAG_R1 \| DN_NDFLAG_R2);
c4106aa8	461	dn->blksize = le16_to_cpu(msg->blksize);
1da177e4 LT	462	dn->priority = 0;
	463	}
	464
	465	write_unlock(&neigh->lock);
	466	neigh_release(neigh);
	467	}
	468
	469	kfree_skb(skb);
	470	return 0;
	471	}
	472
	473	static char dn_find_slot(char base, int max, int priority)
	474	{
	475	int i;
	476	unsigned char *min = NULL;
	477
	478	base += 6; /* skip first id */
	479
	480	for(i = 0; i < max; i++) {
	481	if (!min \|\| (base < min))
	482	min = base;
	483	base += 7; /* find next priority */
	484	}
	485
	486	if (!min)
	487	return NULL;
	488
	489	return (*min < priority) ? (min - 6) : NULL;
	490	}
	491
	492	struct elist_cb_state {
	493	struct net_device *dev;
	494	unsigned char *ptr;
	495	unsigned char *rs;
	496	int t, n;
	497	};
	498
	499	static void neigh_elist_cb(struct neighbour neigh, void _info)
	500	{
	501	struct elist_cb_state *s = _info;
1da177e4 LT	502	struct dn_neigh *dn;
	503
	504	if (neigh->dev != s->dev)
	505	return;
	506
	507	dn = (struct dn_neigh *) neigh;
	508	if (!(dn->flags & (DN_NDFLAG_R1\|DN_NDFLAG_R2)))
	509	return;
	510
1da177e4 LT	511	if (s->t == s->n)
	512	s->rs = dn_find_slot(s->ptr, s->n, dn->priority);
	513	else
	514	s->t++;
	515	if (s->rs == NULL)
	516	return;
	517
	518	dn_dn2eth(s->rs, dn->addr);
	519	s->rs += 6;
	520	*(s->rs) = neigh->nud_state & NUD_CONNECTED ? 0x80 : 0x0;
	521	*(s->rs) \|= dn->priority;
	522	s->rs++;
	523	}
	524
	525	int dn_neigh_elist(struct net_device dev, unsigned char ptr, int n)
	526	{
	527	struct elist_cb_state state;
	528
	529	state.dev = dev;
	530	state.t = 0;
	531	state.n = n;
	532	state.ptr = ptr;
	533	state.rs = ptr;
	534
	535	neigh_for_each(&dn_neigh_table, neigh_elist_cb, &state);
	536
	537	return state.t;
	538	}
	539
	540
	541	#ifdef CONFIG_PROC_FS
	542
	543	static inline void dn_neigh_format_entry(struct seq_file *seq,
	544	struct neighbour *n)
	545	{
	546	struct dn_neigh dn = (struct dn_neigh ) n;
	547	char buf[DN_ASCBUF_LEN];
	548
	549	read_lock(&n->lock);
	550	seq_printf(seq, "%-7s %s%s%s %02x %02d %07ld %-8s\n",
c4106aa8	551	dn_addr2asc(le16_to_cpu(dn->addr), buf),
1da177e4 LT	552	(dn->flags&DN_NDFLAG_R1) ? "1" : "-",
	553	(dn->flags&DN_NDFLAG_R2) ? "2" : "-",
	554	(dn->flags&DN_NDFLAG_P3) ? "3" : "-",
	555	dn->n.nud_state,
	556	atomic_read(&dn->n.refcnt),
	557	dn->blksize,
	558	(dn->n.dev) ? dn->n.dev->name : "?");
	559	read_unlock(&n->lock);
	560	}
	561
	562	static int dn_neigh_seq_show(struct seq_file seq, void v)
	563	{
	564	if (v == SEQ_START_TOKEN) {
	565	seq_puts(seq, "Addr Flags State Use Blksize Dev\n");
	566	} else {
	567	dn_neigh_format_entry(seq, v);
	568	}
	569
	570	return 0;
	571	}
	572
	573	static void dn_neigh_seq_start(struct seq_file seq, loff_t *pos)
	574	{
	575	return neigh_seq_start(seq, pos, &dn_neigh_table,
	576	NEIGH_SEQ_NEIGH_ONLY);
	577	}
	578
56b3d975	579	static const struct seq_operations dn_neigh_seq_ops = {
1da177e4 LT	580	.start = dn_neigh_seq_start,
	581	.next = neigh_seq_next,
	582	.stop = neigh_seq_stop,
	583	.show = dn_neigh_seq_show,
	584	};
	585
	586	static int dn_neigh_seq_open(struct inode inode, struct file file)
	587	{
426b5303 EB	588	return seq_open_net(inode, file, &dn_neigh_seq_ops,
426b5303 EB	589	sizeof(struct neigh_seq_state));
1da177e4 LT	590	}
1da177e4 LT	591
9a32144e	592	static const struct file_operations dn_neigh_seq_fops = {
1da177e4 LT	593	.owner = THIS_MODULE,
	594	.open = dn_neigh_seq_open,
	595	.read = seq_read,
	596	.llseek = seq_lseek,
426b5303	597	.release = seq_release_net,
1da177e4 LT	598	};
	599
	600	#endif
	601
	602	void __init dn_neigh_init(void)
	603	{
d7480fd3	604	neigh_table_init(NEIGH_DN_TABLE, &dn_neigh_table);
d4beaa66 G	605	proc_create("decnet_neigh", S_IRUGO, init_net.proc_net,
d4beaa66 G	606	&dn_neigh_seq_fops);
1da177e4 LT	607	}
	608
	609	void __exit dn_neigh_cleanup(void)
	610	{
ece31ffd	611	remove_proc_entry("decnet_neigh", init_net.proc_net);
d7480fd3	612	neigh_table_clear(NEIGH_DN_TABLE, &dn_neigh_table);
1da177e4	613	}