Initial import

1 files changed, 616 insertions, 0 deletions

diff --git a/net/decnet/dn_neigh.c b/net/decnet/dn_neigh.c
new file mode 100644
index 000000000..4507b188f
--- /dev/null
+++ b/net/decnet/dn_neigh.c
@@ -0,0 +1,616 @@
+/*
+ * 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 sock *sk, 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 sock *sk,
+			  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, sk, 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 sock *sk,
+			   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, sk, 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 sock *sk,
+			    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, sk, skb,
+		       NULL, neigh->dev, dn_neigh_output_packet);
+}
+
+int dn_to_neigh_output(struct sock *sk, 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, sk, skb);
+	if (use_long)
+		return dn_long_output(neigh, sk, skb);
+	else
+		return dn_short_output(neigh, sk, 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 sock *sk, 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 sock *sk, 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);
+}