patch-2.0.35 linux/net/rose/rose_route.c

• Lines: 1000
• Date: Mon Jul 13 13:47:41 1998
• Orig file: v2.0.34/linux/net/rose/rose_route.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.0.34/linux/net/rose/rose_route.c linux/net/rose/rose_route.c
@@ -0,0 +1,999 @@
+/*
+ *	ROSE release 003
+ *
+ *	This code REQUIRES 2.1.0 or higher/ NET3.029
+ *
+ *	This module:
+ *		This module 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; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ *	History
+ *	ROSE 001	Jonathan(G4KLX)	Cloned from nr_route.c.
+ *			Terry(VK2KTJ)	Added support for variable length
+ *					address masks.
+ *	ROSE 002	Jonathan(G4KLX)	Uprated through routing of packets.
+ *					Routing loop detection.
+ *	ROSE 003	Jonathan(G4KLX)	Added use count to neighbours.
+ */
+
+#include <linux/config.h>
+#if defined(CONFIG_ROSE) || defined(CONFIG_ROSE_MODULE)
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <net/ax25.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <net/arp.h>
+#include <linux/if_arp.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <asm/segment.h>
+#include <asm/system.h>
+#include <linux/fcntl.h>
+#include <linux/termios.h>	/* For TIOCINQ/OUTQ */
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/notifier.h>
+#include <linux/firewall.h>
+#include <net/rose.h>
+
+static unsigned int rose_neigh_no = 1;
+
+static struct rose_node  *rose_node_list  = NULL;
+static struct rose_neigh *rose_neigh_list = NULL;
+static struct rose_route *rose_route_list = NULL;
+
+static void rose_remove_neigh(struct rose_neigh *);
+
+/*
+ *	Add a new route to a node, and in the process add the node and the
+ *	neighbour if it is new.
+ */
+static int rose_add_node(struct rose_route_struct *rose_route, struct device *dev)
+{
+	struct rose_node  *rose_node, *rose_tmpn, *rose_tmpp;
+	struct rose_neigh *rose_neigh;
+	unsigned long flags;
+	int i;
+
+	for (rose_node = rose_node_list; rose_node != NULL; rose_node = rose_node->next)
+		if ((rose_node->mask == rose_route->mask) && (rosecmpm(&rose_route->address, &rose_node->address, rose_route->mask) == 0))
+			break;
+
+	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next)
+		if (ax25cmp(&rose_route->neighbour, &rose_neigh->callsign) == 0 && rose_neigh->dev == dev)
+			break;
+
+	if (rose_neigh == NULL) {
+		if ((rose_neigh = (struct rose_neigh *)kmalloc(sizeof(*rose_neigh), GFP_ATOMIC)) == NULL)
+			return -ENOMEM;
+
+		rose_neigh->callsign  = rose_route->neighbour;
+		rose_neigh->digipeat  = NULL;
+		rose_neigh->ax25      = NULL;
+		rose_neigh->dev       = dev;
+		rose_neigh->count     = 0;
+		rose_neigh->use       = 0;
+		rose_neigh->dce_mode  = 0;
+		rose_neigh->number    = rose_neigh_no++;
+		rose_neigh->restarted = 0;
+		skb_queue_head_init(&rose_neigh->queue);
+		rose_neigh->t0timer   = 0;
+		rose_neigh->ftimer    = 0;
+		init_timer(&rose_neigh->timer);
+
+		if (rose_route->ndigis != 0) {
+			if ((rose_neigh->digipeat = kmalloc(sizeof(ax25_digi), GFP_KERNEL)) == NULL) {
+				kfree_s(rose_neigh, sizeof(*rose_neigh));
+				return -ENOMEM;
+			}
+
+			rose_neigh->digipeat->ndigi      = rose_route->ndigis;
+			rose_neigh->digipeat->lastrepeat = -1;
+
+			for (i = 0; i < rose_route->ndigis; i++) {
+				rose_neigh->digipeat->calls[i]    = rose_route->digipeaters[i];
+				rose_neigh->digipeat->repeated[i] = 0;
+			}
+		}
+
+		save_flags(flags); cli();
+		rose_neigh->next = rose_neigh_list;
+		rose_neigh_list  = rose_neigh;
+		restore_flags(flags);
+	}
+
+	/*
+	 * This is a new node to be inserted into the list. Find where it needs
+	 * to be inserted into the list, and insert it. We want to be sure
+	 * to order the list in descending order of mask size to ensure that
+	 * later when we are searching this list the first match will be the
+	 * best match.
+	 */
+	if (rose_node == NULL) {
+		rose_tmpn = rose_node_list;
+		rose_tmpp = NULL;
+
+		while (rose_tmpn != NULL) {
+			if (rose_tmpn->mask > rose_route->mask) {
+				rose_tmpp = rose_tmpn;
+				rose_tmpn = rose_tmpn->next;
+			} else {
+				break;
+			}
+		}
+
+		/* create new node */
+		if ((rose_node = (struct rose_node *)kmalloc(sizeof(*rose_node), GFP_ATOMIC)) == NULL)
+			return -ENOMEM;
+
+		rose_node->address = rose_route->address;
+		rose_node->mask    = rose_route->mask;
+		rose_node->count   = 1;
+		rose_node->neighbour[0] = rose_neigh;
+
+		save_flags(flags); cli();
+
+		if (rose_tmpn == NULL) {
+			if (rose_tmpp == NULL) {	/* Empty list */
+				rose_node_list  = rose_node;
+				rose_node->next = NULL;
+			} else {
+				rose_tmpp->next = rose_node;
+				rose_node->next = NULL;
+			}
+		} else {
+			if (rose_tmpp == NULL) {	/* 1st node */
+				rose_node->next = rose_node_list;
+				rose_node_list  = rose_node;
+			} else {
+				rose_tmpp->next = rose_node;
+				rose_node->next = rose_tmpn;
+			}
+		}
+
+		restore_flags(flags);
+
+		rose_neigh->count++;
+
+		return 0;
+	}
+
+	/* We have space, slot it in */
+	if (rose_node->count < 3) {
+		rose_node->neighbour[rose_node->count] = rose_neigh;
+		rose_node->count++;
+		rose_neigh->count++;
+	}
+
+	return 0;
+}
+
+static void rose_remove_node(struct rose_node *rose_node)
+{
+	struct rose_node *s;
+	unsigned long flags;
+	
+	save_flags(flags);
+	cli();
+
+	if ((s = rose_node_list) == rose_node) {
+		rose_node_list = rose_node->next;
+		restore_flags(flags);
+		kfree_s(rose_node, sizeof(struct rose_node));
+		return;
+	}
+
+	while (s != NULL && s->next != NULL) {
+		if (s->next == rose_node) {
+			s->next = rose_node->next;
+			restore_flags(flags);
+			kfree_s(rose_node, sizeof(struct rose_node));
+			return;
+		}
+
+		s = s->next;
+	}
+
+	restore_flags(flags);
+}
+
+static void rose_remove_neigh(struct rose_neigh *rose_neigh)
+{
+	struct rose_neigh *s;
+	unsigned long flags;
+	struct sk_buff *skb;
+
+	del_timer(&rose_neigh->timer);
+
+	while ((skb = skb_dequeue(&rose_neigh->queue)) != NULL)
+		kfree_skb(skb, FREE_WRITE);
+
+	save_flags(flags);
+	cli();
+
+	if ((s = rose_neigh_list) == rose_neigh) {
+		rose_neigh_list = rose_neigh->next;
+		restore_flags(flags);
+		if (rose_neigh->digipeat != NULL)
+			kfree_s(rose_neigh->digipeat, sizeof(ax25_digi));
+		kfree_s(rose_neigh, sizeof(struct rose_neigh));
+		return;
+	}
+
+	while (s != NULL && s->next != NULL) {
+		if (s->next == rose_neigh) {
+			s->next = rose_neigh->next;
+			restore_flags(flags);
+			if (rose_neigh->digipeat != NULL)
+				kfree_s(rose_neigh->digipeat, sizeof(ax25_digi));
+			kfree_s(rose_neigh, sizeof(struct rose_neigh));
+			return;
+		}
+
+		s = s->next;
+	}
+
+	restore_flags(flags);
+}
+
+static void rose_remove_route(struct rose_route *rose_route)
+{
+	struct rose_route *s;
+	unsigned long flags;
+
+	if (rose_route->neigh1 != NULL)
+		rose_route->neigh1->use--;
+
+	if (rose_route->neigh2 != NULL)
+		rose_route->neigh2->use--;
+
+	save_flags(flags);
+	cli();
+
+	if ((s = rose_route_list) == rose_route) {
+		rose_route_list = rose_route->next;
+		restore_flags(flags);
+		kfree_s(rose_route, sizeof(struct rose_route));
+		return;
+	}
+
+	while (s != NULL && s->next != NULL) {
+		if (s->next == rose_route) {
+			s->next = rose_route->next;
+			restore_flags(flags);
+			kfree_s(rose_route, sizeof(struct rose_route));
+			return;
+		}
+
+		s = s->next;
+	}
+
+	restore_flags(flags);
+}
+
+/*
+ *	"Delete" a node. Strictly speaking remove a route to a node. The node
+ *	is only deleted if no routes are left to it.
+ */
+static int rose_del_node(struct rose_route_struct *rose_route, struct device *dev)
+{
+	struct rose_node  *rose_node;
+	struct rose_neigh *rose_neigh;
+	int i;
+
+	for (rose_node = rose_node_list; rose_node != NULL; rose_node = rose_node->next)
+		if ((rose_node->mask == rose_route->mask) && (rosecmpm(&rose_route->address, &rose_node->address, rose_route->mask) == 0))
+			break;
+
+	if (rose_node == NULL) return -EINVAL;
+
+	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next)
+		if (ax25cmp(&rose_route->neighbour, &rose_neigh->callsign) == 0 && rose_neigh->dev == dev)
+			break;
+
+	if (rose_neigh == NULL) return -EINVAL;
+
+	for (i = 0; i < rose_node->count; i++) {
+		if (rose_node->neighbour[i] == rose_neigh) {
+			rose_neigh->count--;
+
+			if (rose_neigh->count == 0 && rose_neigh->use == 0)
+				rose_remove_neigh(rose_neigh);
+
+			rose_node->count--;
+
+			if (rose_node->count == 0) {
+				rose_remove_node(rose_node);
+			} else {
+				switch (i) {
+					case 0:
+						rose_node->neighbour[0] = rose_node->neighbour[1];
+					case 1:
+						rose_node->neighbour[1] = rose_node->neighbour[2];
+					case 2:
+						break;
+				}
+			}
+
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+/*
+ *	A device has been removed. Remove its routes and neighbours.
+ */
+void rose_rt_device_down(struct device *dev)
+{
+	struct rose_neigh *s, *rose_neigh = rose_neigh_list;
+	struct rose_node  *t, *rose_node;
+	int i;
+
+	while (rose_neigh != NULL) {
+		s          = rose_neigh;
+		rose_neigh = rose_neigh->next;
+
+		if (s->dev == dev) {
+			rose_node = rose_node_list;
+
+			while (rose_node != NULL) {
+				t         = rose_node;
+				rose_node = rose_node->next;
+
+				for (i = 0; i < t->count; i++) {
+					if (t->neighbour[i] == s) {
+						t->count--;
+
+						switch (i) {
+							case 0:
+								t->neighbour[0] = t->neighbour[1];
+							case 1:
+								t->neighbour[1] = t->neighbour[2];
+							case 2:
+								break;
+						}
+					}
+				}
+
+				if (t->count <= 0)
+					rose_remove_node(t);
+			}
+
+			rose_remove_neigh(s);
+		}
+	}
+}
+
+/*
+ *	A device has been removed. Remove its links.
+ */
+void rose_route_device_down(struct device *dev)
+{
+	struct rose_route *s, *rose_route = rose_route_list;
+
+	while (rose_route != NULL) {
+		s          = rose_route;
+		rose_route = rose_route->next;
+
+		if (s->neigh1->dev == dev || s->neigh2->dev == dev)
+			rose_remove_route(s);
+	}
+}
+
+/*
+ *	Clear all nodes and neighbours out, except for neighbours with
+ *	active connections going through them.
+ */
+static int rose_clear_routes(void)
+{
+	struct rose_neigh *s, *rose_neigh = rose_neigh_list;
+	struct rose_node  *t, *rose_node  = rose_node_list;
+
+	while (rose_node != NULL) {
+		t         = rose_node;
+		rose_node = rose_node->next;
+
+		rose_remove_node(t);
+	}
+
+	while (rose_neigh != NULL) {
+		s          = rose_neigh;
+		rose_neigh = rose_neigh->next;
+
+		s->count = 0;
+
+		if (s->use == 0)
+			rose_remove_neigh(s);
+	}
+
+	return 0;
+}
+
+/*
+ *	Check that the device given is a valid AX.25 interface that is "up".
+ */
+struct device *rose_ax25_dev_get(char *devname)
+{
+	struct device *dev;
+
+	if ((dev = dev_get(devname)) == NULL)
+		return NULL;
+
+	if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
+		return dev;
+
+	return NULL;
+}
+
+/*
+ *	Find the first active ROSE device, usually "rose0".
+ */
+struct device *rose_dev_first(void)
+{
+	struct device *dev, *first = NULL;
+
+	for (dev = dev_base; dev != NULL; dev = dev->next)
+		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE)
+			if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
+				first = dev;
+
+	return first;
+}
+
+/*
+ *	Find the ROSE device for the given address.
+ */
+struct device *rose_dev_get(rose_address *addr)
+{
+	struct device *dev;
+
+	for (dev = dev_base; dev != NULL; dev = dev->next)
+		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE && rosecmp(addr, (rose_address *)dev->dev_addr) == 0)
+			return dev;
+
+	return NULL;
+}
+
+struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neigh)
+{
+	struct rose_route *rose_route;
+
+	for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next)
+		if ((rose_route->neigh1 == neigh && rose_route->lci1 == lci) ||
+		    (rose_route->neigh2 == neigh && rose_route->lci2 == lci))
+			return rose_route;
+
+	return NULL;
+}
+
+/*
+ *	Find a neighbour given a ROSE address.
+ */
+struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause, unsigned char *diagnostic)
+{
+	struct rose_node *node;
+	int failed = 0;
+	int i;
+
+	for (node = rose_node_list; node != NULL; node = node->next) {
+		if (rosecmpm(addr, &node->address, node->mask) == 0) {
+			for (i = 0; i < node->count; i++) {
+				if (node->neighbour[i]->ftimer == 0)
+					return node->neighbour[i];
+				else
+					failed = 1;
+			}
+			/* F6FBB : All nodes for this route are out of order */
+			break;
+		}
+	}
+
+	if (failed) {
+		*cause      = ROSE_OUT_OF_ORDER;
+		*diagnostic = 0;
+	} else {
+		*cause      = ROSE_NOT_OBTAINABLE;
+		*diagnostic = 0;
+	}
+
+	return NULL;
+}
+
+/*
+ *	Handle the ioctls that control the routing functions.
+ */
+int rose_rt_ioctl(unsigned int cmd, void *arg)
+{
+	struct rose_route_struct rose_route;
+	struct device *dev;
+	int err;
+
+	switch (cmd) {
+
+		case SIOCADDRT:
+			if ((err = verify_area(VERIFY_READ, arg, sizeof(struct rose_route_struct))) != 0)
+				return err;
+			memcpy_fromfs(&rose_route, arg, sizeof(struct rose_route_struct));
+			if ((dev = rose_ax25_dev_get(rose_route.device)) == NULL)
+				return -EINVAL;
+			if (rose_dev_get(&rose_route.address) != NULL)	/* Can't add routes to ourself */
+				return -EINVAL;
+			if (rose_route.mask > 10) /* Mask can't be more than 10 digits */
+				return -EINVAL;
+
+			return rose_add_node(&rose_route, dev);
+
+		case SIOCDELRT:
+			if ((err = verify_area(VERIFY_READ, arg, sizeof(struct rose_route_struct))) != 0)
+				return err;
+			memcpy_fromfs(&rose_route, arg, sizeof(struct rose_route_struct));
+			if ((dev = rose_ax25_dev_get(rose_route.device)) == NULL)
+				return -EINVAL;
+			return rose_del_node(&rose_route, dev);
+
+		case SIOCRSCLRRT:
+			return rose_clear_routes();
+
+		default:
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void rose_del_route_by_neigh(struct rose_neigh *rose_neigh)
+{
+	struct rose_route *rose_route, *s;
+	struct sk_buff    *skb;
+
+	rose_neigh->restarted = 0;
+	rose_neigh->t0timer   = 0;
+	rose_neigh->ftimer    = sysctl_rose_link_fail_timeout;
+
+	rose_link_set_timer(rose_neigh);
+
+	while ((skb = skb_dequeue(&rose_neigh->queue)) != NULL)
+		kfree_skb(skb, FREE_WRITE);
+
+	rose_route = rose_route_list;
+
+	while (rose_route != NULL) {
+		if ((rose_route->neigh1 == rose_neigh && rose_route->neigh2 == rose_neigh) ||
+		    (rose_route->neigh1 == rose_neigh && rose_route->neigh2 == NULL)       ||
+		    (rose_route->neigh2 == rose_neigh && rose_route->neigh1 == NULL)) {
+			s = rose_route->next;
+			rose_remove_route(rose_route);
+			rose_route = s;
+			continue;
+		}
+
+		if (rose_route->neigh1 == rose_neigh) {
+			rose_route->neigh1->use--;
+			rose_route->neigh1 = NULL;
+			rose_transmit_clear_request(rose_route->neigh2, rose_route->lci2, ROSE_OUT_OF_ORDER, 0);
+		}
+
+		if (rose_route->neigh2 == rose_neigh) {
+			rose_route->neigh2->use--;
+			rose_route->neigh2 = NULL;
+			rose_transmit_clear_request(rose_route->neigh1, rose_route->lci1, ROSE_OUT_OF_ORDER, 0);
+		}
+
+		rose_route = rose_route->next;
+	}
+}
+
+/*
+ * 	A level 2 link has timed out, therefore it appears to be a poor link,
+ *	then don't use that neighbour until it is reset. Blow away all through
+ *	routes and connections using this route.
+ */
+void rose_link_failed(ax25_cb *ax25, int reason)
+{
+	struct rose_neigh *rose_neigh;
+
+	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next)
+		if (rose_neigh->ax25 == ax25)
+			break;
+
+	if (rose_neigh == NULL) return;
+
+	rose_neigh->ax25 = NULL;
+
+	rose_del_route_by_neigh(rose_neigh);
+	rose_kill_by_neigh(rose_neigh);
+}
+
+/*
+ *	A device has been "downed" remove its link status. Blow away all
+ *	through routes and connections that use this device.
+ */
+void rose_link_device_down(struct device *dev)
+{
+	struct rose_neigh *rose_neigh;
+
+	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
+		if (rose_neigh->dev == dev) {
+			rose_del_route_by_neigh(rose_neigh);
+			rose_kill_by_neigh(rose_neigh);
+		}
+	}
+}
+
+/*
+ *	Route a frame to an appropriate AX.25 connection.
+ */
+int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
+{
+	struct rose_neigh *rose_neigh, *new_neigh;
+	struct rose_route *rose_route;
+	struct rose_facilities facilities;
+	rose_address *src_addr, *dest_addr;
+	struct sock *sk;
+	unsigned short frametype;
+	unsigned int lci, new_lci;
+	unsigned char cause, diagnostic;
+	struct device *dev;
+	unsigned long flags;
+
+#ifdef CONFIG_FIREWALL
+	if (call_in_firewall(PF_ROSE, skb->dev, skb->data, NULL) != FW_ACCEPT)
+		return 0;
+#endif
+
+	frametype = skb->data[2];
+	lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
+	src_addr  = (rose_address *)(skb->data + 9);
+	dest_addr = (rose_address *)(skb->data + 4);
+
+	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next)
+		if (ax25cmp(&ax25->dest_addr, &rose_neigh->callsign) == 0 && ax25->device == rose_neigh->dev)
+			break;
+
+	if (rose_neigh == NULL)
+		return 0;
+
+	/*
+	 *	Obviously the link is working, halt the ftimer.
+	 */
+	rose_neigh->ftimer = 0;
+
+	/*
+	 *	LCI of zero is always for us, and its always a restart
+	 * 	frame.
+	 */
+	if (lci == 0) {
+		rose_link_rx_restart(skb, rose_neigh, frametype);
+		return 0;
+	}
+
+	/*
+	 *	Find an existing socket.
+	 */
+	if ((sk = rose_find_socket(lci, rose_neigh)) != NULL) {
+		skb->h.raw = skb->data;
+		return rose_process_rx_frame(sk, skb);
+	}
+
+	/*
+	 *	Is is a Call Request and is it for us ?
+	 */
+	if (frametype == ROSE_CALL_REQUEST)
+		if ((dev = rose_dev_get(dest_addr)) != NULL)
+			return rose_rx_call_request(skb, dev, rose_neigh, lci);
+
+	if (!sysctl_rose_routing_control) {
+		rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 0);
+		return 0;
+	}
+
+	/*
+	 *	Route it to the next in line if we have an entry for it.
+	 */
+	for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next) {
+		if (rose_route->lci1 == lci && rose_route->neigh1 == rose_neigh) {
+			if (rose_route->neigh2 != NULL) {
+				skb->data[0] &= 0xF0;
+				skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
+				skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
+				rose_transmit_link(skb, rose_route->neigh2);
+				if (frametype == ROSE_CLEAR_CONFIRMATION)
+					rose_remove_route(rose_route);
+				return 1;
+			} else {
+				if (frametype == ROSE_CLEAR_CONFIRMATION)
+					rose_remove_route(rose_route);
+				return 0;
+			}
+		}
+		if (rose_route->lci2 == lci && rose_route->neigh2 == rose_neigh) {
+			if (rose_route->neigh1 != NULL) {
+				skb->data[0] &= 0xF0;
+				skb->data[0] |= (rose_route->lci1 >> 8) & 0x0F;
+				skb->data[1]  = (rose_route->lci1 >> 0) & 0xFF;
+				rose_transmit_link(skb, rose_route->neigh1);
+				if (frametype == ROSE_CLEAR_CONFIRMATION)
+					rose_remove_route(rose_route);
+				return 1;
+			} else {
+				if (frametype == ROSE_CLEAR_CONFIRMATION)
+					rose_remove_route(rose_route);
+				return 0;
+			}
+		}
+	}
+
+	/*
+	 *	We know that:
+	 *	1. The frame isn't for us,
+	 *	2. It isn't "owned" by any existing route.
+	 */
+	if (frametype != ROSE_CALL_REQUEST)	/* XXX */
+		return 0;
+
+	if (!rose_parse_facilities(skb, &facilities)) {
+		rose_transmit_clear_request(rose_neigh, lci, ROSE_INVALID_FACILITY, 76);
+		return 0;
+	}
+
+	/*
+	 *	Check for routing loops.
+	 */
+	for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next) {
+		if (rose_route->rand == facilities.rand &&
+		    rosecmp(src_addr, &rose_route->src_addr) == 0 &&
+		    ax25cmp(&facilities.dest_call, &rose_route->src_call) == 0 &&
+		    ax25cmp(&facilities.source_call, &rose_route->dest_call) == 0) {
+			printk(KERN_DEBUG "ROSE: routing loop from %s\n", rose2asc(src_addr));
+			printk(KERN_DEBUG "ROSE:                to %s\n", rose2asc(dest_addr));
+			rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 120);
+			return 0;
+		}
+	}
+
+	if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic)) == NULL) {
+		if (cause == ROSE_NOT_OBTAINABLE)
+			printk(KERN_DEBUG "ROSE: no route to %s\n", rose2asc(dest_addr));
+		rose_transmit_clear_request(rose_neigh, lci, cause, diagnostic);
+		return 0;
+	}
+
+	if ((new_lci = rose_new_lci(new_neigh)) == 0) {
+		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 71);
+		return 0;
+	}
+
+	if ((rose_route = (struct rose_route *)kmalloc(sizeof(*rose_route), GFP_ATOMIC)) == NULL) {
+		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 120);
+		return 0;
+	}
+
+	rose_route->lci1      = lci;
+	rose_route->src_addr  = *src_addr;
+	rose_route->dest_addr = *dest_addr;
+	rose_route->src_call  = facilities.dest_call;
+	rose_route->dest_call = facilities.source_call;
+	rose_route->rand      = facilities.rand;
+	rose_route->neigh1    = rose_neigh;
+	rose_route->lci2      = new_lci;
+	rose_route->neigh2    = new_neigh;
+
+	rose_route->neigh1->use++;
+	rose_route->neigh2->use++;
+
+	save_flags(flags); cli();
+	rose_route->next = rose_route_list;
+	rose_route_list  = rose_route;
+	restore_flags(flags);
+
+	skb->data[0] &= 0xF0;
+	skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
+	skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
+
+	rose_transmit_link(skb, rose_route->neigh2);
+
+	return 1;
+}
+
+int rose_nodes_get_info(char *buffer, char **start, off_t offset,
+		      int length, int dummy)
+{
+	struct rose_node *rose_node;
+	int len     = 0;
+	off_t pos   = 0;
+	off_t begin = 0;
+	int i;
+
+	cli();
+
+	len += sprintf(buffer, "address    mask n neigh neigh neigh\n");
+
+	for (rose_node = rose_node_list; rose_node != NULL; rose_node = rose_node->next) {
+		len += sprintf(buffer + len, "%-10s %04d %d",
+			rose2asc(&rose_node->address),
+			rose_node->mask,
+			rose_node->count);			
+
+		for (i = 0; i < rose_node->count; i++)
+			len += sprintf(buffer + len, " %05d",
+				rose_node->neighbour[i]->number);
+
+		len += sprintf(buffer + len, "\n");
+
+		pos = begin + len;
+
+		if (pos < offset) {
+			len   = 0;
+			begin = pos;
+		}
+
+		if (pos > offset + length)
+			break;
+	}
+
+	sti();
+
+	*start = buffer + (offset - begin);
+	len   -= (offset - begin);
+
+	if (len > length) len = length;
+
+	return len;
+} 
+
+int rose_neigh_get_info(char *buffer, char **start, off_t offset,
+		      int length, int dummy)
+{
+	struct rose_neigh *rose_neigh;
+	int len     = 0;
+	off_t pos   = 0;
+	off_t begin = 0;
+	int i;
+
+	cli();
+
+	len += sprintf(buffer, "addr  callsign  dev  count use mode restart  t0  tf digipeaters\n");
+
+	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
+		len += sprintf(buffer + len, "%05d %-9s %-4s   %3d %3d  %3s     %3s %3d %3d",
+			rose_neigh->number,
+			ax2asc(&rose_neigh->callsign),
+			rose_neigh->dev ? rose_neigh->dev->name : "???",
+			rose_neigh->count,
+			rose_neigh->use,
+			(rose_neigh->dce_mode) ? "DCE" : "DTE",
+			(rose_neigh->restarted) ? "yes" : "no",
+			rose_neigh->t0timer / ROSE_SLOWHZ,
+			rose_neigh->ftimer  / ROSE_SLOWHZ);
+
+		if (rose_neigh->digipeat != NULL) {
+			for (i = 0; i < rose_neigh->digipeat->ndigi; i++)
+				len += sprintf(buffer + len, " %s", ax2asc(&rose_neigh->digipeat->calls[i]));
+		}
+
+		len += sprintf(buffer + len, "\n");
+
+		pos = begin + len;
+
+		if (pos < offset) {
+			len   = 0;
+			begin = pos;
+		}
+
+		if (pos > offset + length)
+			break;
+	}
+
+	sti();
+
+	*start = buffer + (offset - begin);
+	len   -= (offset - begin);
+
+	if (len > length) len = length;
+
+	return len;
+} 
+
+int rose_routes_get_info(char *buffer, char **start, off_t offset,
+		      int length, int dummy)
+{
+	struct rose_route *rose_route;
+	int len     = 0;
+	off_t pos   = 0;
+	off_t begin = 0;
+
+	cli();
+
+	len += sprintf(buffer, "lci  address     callsign   neigh  <-> lci  address     callsign   neigh\n");
+
+	for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next) {
+		if (rose_route->neigh1 != NULL) {
+			len += sprintf(buffer + len, "%3.3X  %-10s  %-9s  %05d      ",
+				rose_route->lci1,
+				rose2asc(&rose_route->src_addr),
+				ax2asc(&rose_route->src_call),
+				rose_route->neigh1->number);
+		} else {
+			len += sprintf(buffer + len, "000  *           *          00000      ");
+		}
+
+		if (rose_route->neigh2 != NULL) {
+			len += sprintf(buffer + len, "%3.3X  %-10s  %-9s  %05d\n",
+				rose_route->lci2,
+				rose2asc(&rose_route->dest_addr),
+				ax2asc(&rose_route->dest_call),
+				rose_route->neigh2->number);
+		} else {
+			len += sprintf(buffer + len, "000  *           *          00000\n");
+		}
+
+		pos = begin + len;
+
+		if (pos < offset) {
+			len   = 0;
+			begin = pos;
+		}
+
+		if (pos > offset + length)
+			break;
+	}
+
+	sti();
+
+	*start = buffer + (offset - begin);
+	len   -= (offset - begin);
+
+	if (len > length) len = length;
+
+	return len;
+} 
+
+#ifdef MODULE
+
+/*
+ *	Release all memory associated with ROSE routing structures.
+ */
+void rose_rt_free(void)
+{
+	struct rose_neigh *s, *rose_neigh = rose_neigh_list;
+	struct rose_node  *t, *rose_node  = rose_node_list;
+	struct rose_route *u, *rose_route = rose_route_list;
+
+	while (rose_neigh != NULL) {
+		s          = rose_neigh;
+		rose_neigh = rose_neigh->next;
+
+		rose_remove_neigh(s);
+	}
+
+	while (rose_node != NULL) {
+		t         = rose_node;
+		rose_node = rose_node->next;
+
+		rose_remove_node(t);
+	}
+
+	while (rose_route != NULL) {
+		u          = rose_route;
+		rose_route = rose_route->next;
+
+		rose_remove_route(u);
+	}
+}
+
+#endif
+
+#endif