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/*
* NET/ROM release 007
*
* This code REQUIRES 2.1.15 or higher/ NET3.038
*
* 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
* NET/ROM 001 Jonathan(G4KLX) First attempt.
* NET/ROM 003 Jonathan(G4KLX) Use SIOCADDRT/SIOCDELRT ioctl values
* for NET/ROM routes.
* Use '*' for a blank mnemonic in /proc/net/nr_nodes.
* Change default quality for new neighbour when same
* as node callsign.
* Alan Cox(GW4PTS) Added the firewall hooks.
* NET/ROM 006 Jonathan(G4KLX) Added the setting of digipeated neighbours.
* Tomi(OH2BNS) Routing quality and link failure changes.
*/
#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/uaccess.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/netfilter.h>
#include <linux/init.h>
#include <net/netrom.h>
static unsigned int nr_neigh_no = 1;
static struct nr_node *nr_node_list;
static struct nr_neigh *nr_neigh_list;
static void nr_remove_neigh(struct nr_neigh *);
/*
* Add a new route to a node, and in the process add the node and the
* neighbour if it is new.
*/
static int nr_add_node(ax25_address *nr, const char *mnemonic, ax25_address *ax25,
ax25_digi *ax25_digi, struct net_device *dev, int quality, int obs_count)
{
struct nr_node *nr_node;
struct nr_neigh *nr_neigh;
struct nr_route nr_route;
unsigned long flags;
int i, found;
if (nr_dev_get(nr) != NULL) /* Can't add routes to ourself */
return -EINVAL;
for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next)
if (ax25cmp(nr, &nr_node->callsign) == 0)
break;
for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next)
if (ax25cmp(ax25, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev)
break;
/*
* The L2 link to a neighbour has failed in the past
* and now a frame comes from this neighbour. We assume
* it was a temporary trouble with the link and reset the
* routes now (and not wait for a node broadcast).
*/
if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
struct nr_node *node;
for (node = nr_node_list; node != NULL; node = node->next)
for (i = 0; i < node->count; i++)
if (node->routes[i].neighbour == nr_neigh)
if (i < node->which)
node->which = i;
}
if (nr_neigh != NULL)
nr_neigh->failed = 0;
if (quality == 0 && nr_neigh != NULL && nr_node != NULL)
return 0;
if (nr_neigh == NULL) {
if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
return -ENOMEM;
nr_neigh->callsign = *ax25;
nr_neigh->digipeat = NULL;
nr_neigh->ax25 = NULL;
nr_neigh->dev = dev;
nr_neigh->quality = sysctl_netrom_default_path_quality;
nr_neigh->locked = 0;
nr_neigh->count = 0;
nr_neigh->number = nr_neigh_no++;
nr_neigh->failed = 0;
if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
if ((nr_neigh->digipeat = kmalloc(sizeof(*ax25_digi), GFP_KERNEL)) == NULL) {
kfree(nr_neigh);
return -ENOMEM;
}
memcpy(nr_neigh->digipeat, ax25_digi, sizeof(ax25_digi));
}
save_flags(flags);
cli();
nr_neigh->next = nr_neigh_list;
nr_neigh_list = nr_neigh;
restore_flags(flags);
}
if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
nr_neigh->quality = quality;
if (nr_node == NULL) {
if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL)
return -ENOMEM;
nr_node->callsign = *nr;
strcpy(nr_node->mnemonic, mnemonic);
nr_node->which = 0;
nr_node->count = 1;
nr_node->routes[0].quality = quality;
nr_node->routes[0].obs_count = obs_count;
nr_node->routes[0].neighbour = nr_neigh;
save_flags(flags);
cli();
nr_node->next = nr_node_list;
nr_node_list = nr_node;
restore_flags(flags);
nr_neigh->count++;
return 0;
}
if (quality != 0)
strcpy(nr_node->mnemonic, mnemonic);
for (found = 0, i = 0; i < nr_node->count; i++) {
if (nr_node->routes[i].neighbour == nr_neigh) {
nr_node->routes[i].quality = quality;
nr_node->routes[i].obs_count = obs_count;
found = 1;
break;
}
}
if (!found) {
/* We have space at the bottom, slot it in */
if (nr_node->count < 3) {
nr_node->routes[2] = nr_node->routes[1];
nr_node->routes[1] = nr_node->routes[0];
nr_node->routes[0].quality = quality;
nr_node->routes[0].obs_count = obs_count;
nr_node->routes[0].neighbour = nr_neigh;
nr_node->which++;
nr_node->count++;
nr_neigh->count++;
} else {
/* It must be better than the worst */
if (quality > nr_node->routes[2].quality) {
nr_node->routes[2].neighbour->count--;
if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
nr_remove_neigh(nr_node->routes[2].neighbour);
nr_node->routes[2].quality = quality;
nr_node->routes[2].obs_count = obs_count;
nr_node->routes[2].neighbour = nr_neigh;
nr_neigh->count++;
}
}
}
/* Now re-sort the routes in quality order */
switch (nr_node->count) {
case 3:
if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
switch (nr_node->which) {
case 0: nr_node->which = 1; break;
case 1: nr_node->which = 0; break;
default: break;
}
nr_route = nr_node->routes[0];
nr_node->routes[0] = nr_node->routes[1];
nr_node->routes[1] = nr_route;
}
if (nr_node->routes[2].quality > nr_node->routes[1].quality) {
switch (nr_node->which) {
case 1: nr_node->which = 2; break;
case 2: nr_node->which = 1; break;
default: break;
}
nr_route = nr_node->routes[1];
nr_node->routes[1] = nr_node->routes[2];
nr_node->routes[2] = nr_route;
}
case 2:
if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
switch (nr_node->which) {
case 0: nr_node->which = 1; break;
case 1: nr_node->which = 0; break;
default: break;
}
nr_route = nr_node->routes[0];
nr_node->routes[0] = nr_node->routes[1];
nr_node->routes[1] = nr_route;
}
case 1:
break;
}
for (i = 0; i < nr_node->count; i++) {
if (nr_node->routes[i].neighbour == nr_neigh) {
if (i < nr_node->which)
nr_node->which = i;
break;
}
}
return 0;
}
static void nr_remove_node(struct nr_node *nr_node)
{
struct nr_node *s;
unsigned long flags;
save_flags(flags);
cli();
if ((s = nr_node_list) == nr_node) {
nr_node_list = nr_node->next;
restore_flags(flags);
kfree(nr_node);
return;
}
while (s != NULL && s->next != NULL) {
if (s->next == nr_node) {
s->next = nr_node->next;
restore_flags(flags);
kfree(nr_node);
return;
}
s = s->next;
}
restore_flags(flags);
}
static void nr_remove_neigh(struct nr_neigh *nr_neigh)
{
struct nr_neigh *s;
unsigned long flags;
save_flags(flags);
cli();
if ((s = nr_neigh_list) == nr_neigh) {
nr_neigh_list = nr_neigh->next;
restore_flags(flags);
if (nr_neigh->digipeat != NULL)
kfree(nr_neigh->digipeat);
kfree(nr_neigh);
return;
}
while (s != NULL && s->next != NULL) {
if (s->next == nr_neigh) {
s->next = nr_neigh->next;
restore_flags(flags);
if (nr_neigh->digipeat != NULL)
kfree(nr_neigh->digipeat);
kfree(nr_neigh);
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 nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
{
struct nr_node *nr_node;
struct nr_neigh *nr_neigh;
int i;
for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next)
if (ax25cmp(callsign, &nr_node->callsign) == 0)
break;
if (nr_node == NULL) return -EINVAL;
for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next)
if (ax25cmp(neighbour, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev)
break;
if (nr_neigh == NULL) return -EINVAL;
for (i = 0; i < nr_node->count; i++) {
if (nr_node->routes[i].neighbour == nr_neigh) {
nr_neigh->count--;
if (nr_neigh->count == 0 && !nr_neigh->locked)
nr_remove_neigh(nr_neigh);
nr_node->count--;
if (nr_node->count == 0) {
nr_remove_node(nr_node);
} else {
switch (i) {
case 0:
nr_node->routes[0] = nr_node->routes[1];
case 1:
nr_node->routes[1] = nr_node->routes[2];
case 2:
break;
}
}
return 0;
}
}
return -EINVAL;
}
/*
* Lock a neighbour with a quality.
*/
static int nr_add_neigh(ax25_address *callsign, ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
{
struct nr_neigh *nr_neigh;
unsigned long flags;
for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next) {
if (ax25cmp(callsign, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev) {
nr_neigh->quality = quality;
nr_neigh->locked = 1;
return 0;
}
}
if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
return -ENOMEM;
nr_neigh->callsign = *callsign;
nr_neigh->digipeat = NULL;
nr_neigh->ax25 = NULL;
nr_neigh->dev = dev;
nr_neigh->quality = quality;
nr_neigh->locked = 1;
nr_neigh->count = 0;
nr_neigh->number = nr_neigh_no++;
nr_neigh->failed = 0;
if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
if ((nr_neigh->digipeat = kmalloc(sizeof(*ax25_digi), GFP_KERNEL)) == NULL) {
kfree(nr_neigh);
return -ENOMEM;
}
memcpy(nr_neigh->digipeat, ax25_digi, sizeof(ax25_digi));
}
save_flags(flags);
cli();
nr_neigh->next = nr_neigh_list;
nr_neigh_list = nr_neigh;
restore_flags(flags);
return 0;
}
/*
* "Delete" a neighbour. The neighbour is only removed if the number
* of nodes that may use it is zero.
*/
static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
{
struct nr_neigh *nr_neigh;
for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next)
if (ax25cmp(callsign, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev)
break;
if (nr_neigh == NULL) return -EINVAL;
nr_neigh->quality = quality;
nr_neigh->locked = 0;
if (nr_neigh->count == 0)
nr_remove_neigh(nr_neigh);
return 0;
}
/*
* Decrement the obsolescence count by one. If a route is reduced to a
* count of zero, remove it. Also remove any unlocked neighbours with
* zero nodes routing via it.
*/
static int nr_dec_obs(void)
{
struct nr_neigh *nr_neigh;
struct nr_node *s, *nr_node;
int i;
nr_node = nr_node_list;
while (nr_node != NULL) {
s = nr_node;
nr_node = nr_node->next;
for (i = 0; i < s->count; i++) {
switch (s->routes[i].obs_count) {
case 0: /* A locked entry */
break;
case 1: /* From 1 -> 0 */
nr_neigh = s->routes[i].neighbour;
nr_neigh->count--;
if (nr_neigh->count == 0 && !nr_neigh->locked)
nr_remove_neigh(nr_neigh);
s->count--;
switch (i) {
case 0:
s->routes[0] = s->routes[1];
case 1:
s->routes[1] = s->routes[2];
case 2:
break;
}
break;
default:
s->routes[i].obs_count--;
break;
}
}
if (s->count <= 0)
nr_remove_node(s);
}
return 0;
}
/*
* A device has been removed. Remove its routes and neighbours.
*/
void nr_rt_device_down(struct net_device *dev)
{
struct nr_neigh *s, *nr_neigh = nr_neigh_list;
struct nr_node *t, *nr_node;
int i;
while (nr_neigh != NULL) {
s = nr_neigh;
nr_neigh = nr_neigh->next;
if (s->dev == dev) {
nr_node = nr_node_list;
while (nr_node != NULL) {
t = nr_node;
nr_node = nr_node->next;
for (i = 0; i < t->count; i++) {
if (t->routes[i].neighbour == s) {
t->count--;
switch (i) {
case 0:
t->routes[0] = t->routes[1];
case 1:
t->routes[1] = t->routes[2];
case 2:
break;
}
}
}
if (t->count <= 0)
nr_remove_node(t);
}
nr_remove_neigh(s);
}
}
}
/*
* Check that the device given is a valid AX.25 interface that is "up".
* Or a valid ethernet interface with an AX.25 callsign binding.
*/
static struct net_device *nr_ax25_dev_get(char *devname)
{
struct net_device *dev;
if ((dev = dev_get_by_name(devname)) == NULL)
return NULL;
if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
return dev;
dev_put(dev);
return NULL;
}
/*
* Find the first active NET/ROM device, usually "nr0".
*/
struct net_device *nr_dev_first(void)
{
struct net_device *dev, *first = NULL;
read_lock(&dev_base_lock);
for (dev = dev_base; dev != NULL; dev = dev->next) {
if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
first = dev;
}
read_unlock(&dev_base_lock);
return first;
}
/*
* Find the NET/ROM device for the given callsign.
*/
struct net_device *nr_dev_get(ax25_address *addr)
{
struct net_device *dev;
read_lock(&dev_base_lock);
for (dev = dev_base; dev != NULL; dev = dev->next) {
if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM && ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
dev_hold(dev);
goto out;
}
}
out:
read_unlock(&dev_base_lock);
return dev;
}
static ax25_digi *nr_call_to_digi(int ndigis, ax25_address *digipeaters)
{
static ax25_digi ax25_digi;
int i;
if (ndigis == 0)
return NULL;
for (i = 0; i < ndigis; i++) {
ax25_digi.calls[i] = digipeaters[i];
ax25_digi.repeated[i] = 0;
}
ax25_digi.ndigi = ndigis;
ax25_digi.lastrepeat = -1;
return &ax25_digi;
}
/*
* Handle the ioctls that control the routing functions.
*/
int nr_rt_ioctl(unsigned int cmd, void *arg)
{
struct nr_route_struct nr_route;
struct net_device *dev;
switch (cmd) {
case SIOCADDRT:
if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
return -EFAULT;
if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
return -EINVAL;
if (nr_route.ndigis < 0 || nr_route.ndigis > AX25_MAX_DIGIS)
return -EINVAL;
switch (nr_route.type) {
case NETROM_NODE:
return nr_add_node(&nr_route.callsign,
nr_route.mnemonic,
&nr_route.neighbour,
nr_call_to_digi(nr_route.ndigis, nr_route.digipeaters),
dev, nr_route.quality,
nr_route.obs_count);
case NETROM_NEIGH:
return nr_add_neigh(&nr_route.callsign,
nr_call_to_digi(nr_route.ndigis, nr_route.digipeaters),
dev, nr_route.quality);
default:
return -EINVAL;
}
case SIOCDELRT:
if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
return -EFAULT;
if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
return -EINVAL;
switch (nr_route.type) {
case NETROM_NODE:
return nr_del_node(&nr_route.callsign,
&nr_route.neighbour, dev);
case NETROM_NEIGH:
return nr_del_neigh(&nr_route.callsign,
dev, nr_route.quality);
default:
return -EINVAL;
}
case SIOCNRDECOBS:
return nr_dec_obs();
default:
return -EINVAL;
}
return 0;
}
/*
* 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.
*/
void nr_link_failed(ax25_cb *ax25, int reason)
{
struct nr_neigh *nr_neigh;
struct nr_node *nr_node;
for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next)
if (nr_neigh->ax25 == ax25)
break;
if (nr_neigh == NULL) return;
nr_neigh->ax25 = NULL;
if (++nr_neigh->failed < sysctl_netrom_link_fails_count) return;
for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next)
if (nr_node->which < nr_node->count && nr_node->routes[nr_node->which].neighbour == nr_neigh)
nr_node->which++;
}
/*
* Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
* indicates an internally generated frame.
*/
int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
{
ax25_address *nr_src, *nr_dest;
struct nr_neigh *nr_neigh;
struct nr_node *nr_node;
struct net_device *dev;
unsigned char *dptr;
nr_src = (ax25_address *)(skb->data + 0);
nr_dest = (ax25_address *)(skb->data + 7);
if (ax25 != NULL)
nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
ax25->ax25_dev->dev, 0, sysctl_netrom_obsolescence_count_initialiser);
if ((dev = nr_dev_get(nr_dest)) != NULL) { /* Its for me */
if (ax25 == NULL) /* Its from me */
return nr_loopback_queue(skb);
else
return nr_rx_frame(skb, dev);
}
if (!sysctl_netrom_routing_control && ax25 != NULL)
return 0;
/* Its Time-To-Live has expired */
if (--skb->data[14] == 0)
return 0;
for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next)
if (ax25cmp(nr_dest, &nr_node->callsign) == 0)
break;
if (nr_node == NULL || nr_node->which >= nr_node->count)
return 0;
nr_neigh = nr_node->routes[nr_node->which].neighbour;
if ((dev = nr_dev_first()) == NULL)
return 0;
dptr = skb_push(skb, 1);
*dptr = AX25_P_NETROM;
nr_neigh->ax25 = ax25_send_frame(skb, 256, (ax25_address *)dev->dev_addr, &nr_neigh->callsign, nr_neigh->digipeat, nr_neigh->dev);
return (nr_neigh->ax25 != NULL);
}
int nr_nodes_get_info(char *buffer, char **start, off_t offset, int length)
{
struct nr_node *nr_node;
int len = 0;
off_t pos = 0;
off_t begin = 0;
int i;
cli();
len += sprintf(buffer, "callsign mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next) {
len += sprintf(buffer + len, "%-9s %-7s %d %d",
ax2asc(&nr_node->callsign),
(nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
nr_node->which + 1,
nr_node->count);
for (i = 0; i < nr_node->count; i++) {
len += sprintf(buffer + len, " %3d %d %05d",
nr_node->routes[i].quality,
nr_node->routes[i].obs_count,
nr_node->routes[i].neighbour->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 nr_neigh_get_info(char *buffer, char **start, off_t offset, int length)
{
struct nr_neigh *nr_neigh;
int len = 0;
off_t pos = 0;
off_t begin = 0;
int i;
cli();
len += sprintf(buffer, "addr callsign dev qual lock count failed digipeaters\n");
for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next) {
len += sprintf(buffer + len, "%05d %-9s %-4s %3d %d %3d %3d",
nr_neigh->number,
ax2asc(&nr_neigh->callsign),
nr_neigh->dev ? nr_neigh->dev->name : "???",
nr_neigh->quality,
nr_neigh->locked,
nr_neigh->count,
nr_neigh->failed);
if (nr_neigh->digipeat != NULL) {
for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
len += sprintf(buffer + len, " %s", ax2asc(&nr_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;
}
/*
* Free all memory associated with the nodes and routes lists.
*/
void __exit nr_rt_free(void)
{
struct nr_neigh *s, *nr_neigh = nr_neigh_list;
struct nr_node *t, *nr_node = nr_node_list;
while (nr_node != NULL) {
t = nr_node;
nr_node = nr_node->next;
nr_remove_node(t);
}
while (nr_neigh != NULL) {
s = nr_neigh;
nr_neigh = nr_neigh->next;
nr_remove_neigh(s);
}
}
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