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/*
* AX.25 release 037
*
* 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.
*
* Other kernels modules in this kit are generally BSD derived. See the copyright headers.
*
*
* History
* AX.25 020 Jonathan(G4KLX) First go.
* AX.25 022 Jonathan(G4KLX) Added the actual meat to this - we now have a nice heard list.
* AX.25 025 Alan(GW4PTS) First cut at autobinding by route scan.
* AX.25 028b Jonathan(G4KLX) Extracted AX25 control block from the
* sock structure. Device removal now
* removes the heard structure.
* AX.25 029 Steven(GW7RRM) Added /proc information for uid/callsign mapping.
* Jonathan(G4KLX) Handling of IP mode in the routing list and /proc entry.
* AX.25 030 Jonathan(G4KLX) Added digi-peaters to routing table, and
* ioctls to manipulate them. Added port
* configuration.
* AX.25 031 Jonathan(G4KLX) Added concept of default route.
* Joerg(DL1BKE) ax25_rt_build_path() find digipeater list and device by
* destination call. Needed for IP routing via digipeater
* Jonathan(G4KLX) Added routing for IP datagram packets.
* Joerg(DL1BKE) Changed routing for IP datagram and VC to use a default
* route if available. Does not overwrite default routes
* on route-table overflow anymore.
* Joerg(DL1BKE) Fixed AX.25 routing of IP datagram and VC, new ioctl()
* "SIOCAX25OPTRT" to set IP mode and a 'permanent' flag
* on routes.
* AX.25 033 Jonathan(G4KLX) Remove auto-router.
* Joerg(DL1BKE) Moved BPQ Ethernet driver to separate device.
* AX.25 035 Frederic(F1OAT) Support for pseudo-digipeating.
* Jonathan(G4KLX) Support for packet forwarding.
* Arnaldo C. Melo s/suser/capable/
*/
#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 <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/mm.h>
#include <linux/interrupt.h>
#include <linux/init.h>
static ax25_route *ax25_route_list;
static ax25_route *ax25_find_route(ax25_address *, struct net_device *);
/*
* small macro to drop non-digipeated digipeaters and reverse path
*/
static inline void ax25_route_invert(ax25_digi *in, ax25_digi *out)
{
int k;
for (k = 0; k < in->ndigi; k++)
if (!in->repeated[k])
break;
in->ndigi = k;
ax25_digi_invert(in, out);
}
void ax25_rt_device_down(struct net_device *dev)
{
ax25_route *s, *t, *ax25_rt = ax25_route_list;
while (ax25_rt != NULL) {
s = ax25_rt;
ax25_rt = ax25_rt->next;
if (s->dev == dev) {
if (ax25_route_list == s) {
ax25_route_list = s->next;
if (s->digipeat != NULL)
kfree(s->digipeat);
kfree(s);
} else {
for (t = ax25_route_list; t != NULL; t = t->next) {
if (t->next == s) {
t->next = s->next;
if (s->digipeat != NULL)
kfree(s->digipeat);
kfree(s);
break;
}
}
}
}
}
}
int ax25_rt_ioctl(unsigned int cmd, void *arg)
{
unsigned long flags;
ax25_route *s, *t, *ax25_rt;
struct ax25_routes_struct route;
struct ax25_route_opt_struct rt_option;
ax25_dev *ax25_dev;
int i;
switch (cmd) {
case SIOCADDRT:
if (copy_from_user(&route, arg, sizeof(route)))
return -EFAULT;
if ((ax25_dev = ax25_addr_ax25dev(&route.port_addr)) == NULL)
return -EINVAL;
if (route.digi_count > AX25_MAX_DIGIS)
return -EINVAL;
for (ax25_rt = ax25_route_list; ax25_rt != NULL; ax25_rt = ax25_rt->next) {
if (ax25cmp(&ax25_rt->callsign, &route.dest_addr) == 0 && ax25_rt->dev == ax25_dev->dev) {
if (ax25_rt->digipeat != NULL) {
kfree(ax25_rt->digipeat);
ax25_rt->digipeat = NULL;
}
if (route.digi_count != 0) {
if ((ax25_rt->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL)
return -ENOMEM;
ax25_rt->digipeat->lastrepeat = -1;
ax25_rt->digipeat->ndigi = route.digi_count;
for (i = 0; i < route.digi_count; i++) {
ax25_rt->digipeat->repeated[i] = 0;
ax25_rt->digipeat->calls[i] = route.digi_addr[i];
}
}
return 0;
}
}
if ((ax25_rt = kmalloc(sizeof(ax25_route), GFP_ATOMIC)) == NULL)
return -ENOMEM;
ax25_rt->callsign = route.dest_addr;
ax25_rt->dev = ax25_dev->dev;
ax25_rt->digipeat = NULL;
ax25_rt->ip_mode = ' ';
if (route.digi_count != 0) {
if ((ax25_rt->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL) {
kfree(ax25_rt);
return -ENOMEM;
}
ax25_rt->digipeat->lastrepeat = -1;
ax25_rt->digipeat->ndigi = route.digi_count;
for (i = 0; i < route.digi_count; i++) {
ax25_rt->digipeat->repeated[i] = 0;
ax25_rt->digipeat->calls[i] = route.digi_addr[i];
}
}
save_flags(flags); cli();
ax25_rt->next = ax25_route_list;
ax25_route_list = ax25_rt;
restore_flags(flags);
break;
case SIOCDELRT:
if (copy_from_user(&route, arg, sizeof(route)))
return -EFAULT;
if ((ax25_dev = ax25_addr_ax25dev(&route.port_addr)) == NULL)
return -EINVAL;
ax25_rt = ax25_route_list;
while (ax25_rt != NULL) {
s = ax25_rt;
ax25_rt = ax25_rt->next;
if (s->dev == ax25_dev->dev && ax25cmp(&route.dest_addr, &s->callsign) == 0) {
if (ax25_route_list == s) {
ax25_route_list = s->next;
if (s->digipeat != NULL)
kfree(s->digipeat);
kfree(s);
} else {
for (t = ax25_route_list; t != NULL; t = t->next) {
if (t->next == s) {
t->next = s->next;
if (s->digipeat != NULL)
kfree(s->digipeat);
kfree(s);
break;
}
}
}
}
}
break;
case SIOCAX25OPTRT:
if (copy_from_user(&rt_option, arg, sizeof(rt_option)))
return -EFAULT;
if ((ax25_dev = ax25_addr_ax25dev(&rt_option.port_addr)) == NULL)
return -EINVAL;
for (ax25_rt = ax25_route_list; ax25_rt != NULL; ax25_rt = ax25_rt->next) {
if (ax25_rt->dev == ax25_dev->dev && ax25cmp(&rt_option.dest_addr, &ax25_rt->callsign) == 0) {
switch (rt_option.cmd) {
case AX25_SET_RT_IPMODE:
switch (rt_option.arg) {
case ' ':
case 'D':
case 'V':
ax25_rt->ip_mode = rt_option.arg;
break;
default:
return -EINVAL;
}
break;
default:
return -EINVAL;
}
}
}
break;
default:
return -EINVAL;
}
return 0;
}
int ax25_rt_get_info(char *buffer, char **start, off_t offset, int length)
{
ax25_route *ax25_rt;
int len = 0;
off_t pos = 0;
off_t begin = 0;
char *callsign;
int i;
cli();
len += sprintf(buffer, "callsign dev mode digipeaters\n");
for (ax25_rt = ax25_route_list; ax25_rt != NULL; ax25_rt = ax25_rt->next) {
if (ax25cmp(&ax25_rt->callsign, &null_ax25_address) == 0)
callsign = "default";
else
callsign = ax2asc(&ax25_rt->callsign);
len += sprintf(buffer + len, "%-9s %-4s",
callsign,
ax25_rt->dev ? ax25_rt->dev->name : "???");
switch (ax25_rt->ip_mode) {
case 'V':
len += sprintf(buffer + len, " vc");
break;
case 'D':
len += sprintf(buffer + len, " dg");
break;
default:
len += sprintf(buffer + len, " *");
break;
}
if (ax25_rt->digipeat != NULL)
for (i = 0; i < ax25_rt->digipeat->ndigi; i++)
len += sprintf(buffer + len, " %s", ax2asc(&ax25_rt->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;
}
/*
* Find AX.25 route
*/
static ax25_route *ax25_find_route(ax25_address *addr, struct net_device *dev)
{
ax25_route *ax25_spe_rt = NULL;
ax25_route *ax25_def_rt = NULL;
ax25_route *ax25_rt;
/*
* Bind to the physical interface we heard them on, or the default
* route if none is found;
*/
for (ax25_rt = ax25_route_list; ax25_rt != NULL; ax25_rt = ax25_rt->next) {
if (dev == NULL) {
if (ax25cmp(&ax25_rt->callsign, addr) == 0 && ax25_rt->dev != NULL)
ax25_spe_rt = ax25_rt;
if (ax25cmp(&ax25_rt->callsign, &null_ax25_address) == 0 && ax25_rt->dev != NULL)
ax25_def_rt = ax25_rt;
} else {
if (ax25cmp(&ax25_rt->callsign, addr) == 0 && ax25_rt->dev == dev)
ax25_spe_rt = ax25_rt;
if (ax25cmp(&ax25_rt->callsign, &null_ax25_address) == 0 && ax25_rt->dev == dev)
ax25_def_rt = ax25_rt;
}
}
if (ax25_spe_rt != NULL)
return ax25_spe_rt;
return ax25_def_rt;
}
/*
* Adjust path: If you specify a default route and want to connect
* a target on the digipeater path but w/o having a special route
* set before, the path has to be truncated from your target on.
*/
static inline void ax25_adjust_path(ax25_address *addr, ax25_digi *digipeat)
{
int k;
for (k = 0; k < digipeat->ndigi; k++) {
if (ax25cmp(addr, &digipeat->calls[k]) == 0)
break;
}
digipeat->ndigi = k;
}
/*
* Find which interface to use.
*/
int ax25_rt_autobind(ax25_cb *ax25, ax25_address *addr)
{
ax25_route *ax25_rt;
ax25_address *call;
if ((ax25_rt = ax25_find_route(addr, NULL)) == NULL)
return -EHOSTUNREACH;
if ((ax25->ax25_dev = ax25_dev_ax25dev(ax25_rt->dev)) == NULL)
return -EHOSTUNREACH;
if ((call = ax25_findbyuid(current->euid)) == NULL) {
if (ax25_uid_policy && !capable(CAP_NET_BIND_SERVICE))
return -EPERM;
call = (ax25_address *)ax25->ax25_dev->dev->dev_addr;
}
ax25->source_addr = *call;
if (ax25_rt->digipeat != NULL) {
if ((ax25->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL)
return -ENOMEM;
memcpy(ax25->digipeat, ax25_rt->digipeat, sizeof(ax25_digi));
ax25_adjust_path(addr, ax25->digipeat);
}
if (ax25->sk != NULL)
ax25->sk->zapped = 0;
return 0;
}
/*
* dl1bke 960117: build digipeater path
* dl1bke 960301: use the default route if it exists
*/
ax25_route *ax25_rt_find_route(ax25_address *addr, struct net_device *dev)
{
static ax25_route route;
ax25_route *ax25_rt;
if ((ax25_rt = ax25_find_route(addr, dev)) == NULL) {
route.next = NULL;
route.callsign = *addr;
route.dev = dev;
route.digipeat = NULL;
route.ip_mode = ' ';
return &route;
}
return ax25_rt;
}
struct sk_buff *ax25_rt_build_path(struct sk_buff *skb, ax25_address *src, ax25_address *dest, ax25_digi *digi)
{
struct sk_buff *skbn;
unsigned char *bp;
int len;
len = digi->ndigi * AX25_ADDR_LEN;
if (skb_headroom(skb) < len) {
if ((skbn = skb_realloc_headroom(skb, len)) == NULL) {
printk(KERN_CRIT "AX.25: ax25_dg_build_path - out of memory\n");
return NULL;
}
if (skb->sk != NULL)
skb_set_owner_w(skbn, skb->sk);
kfree_skb(skb);
skb = skbn;
}
bp = skb_push(skb, len);
ax25_addr_build(bp, src, dest, digi, AX25_COMMAND, AX25_MODULUS);
return skb;
}
/*
* Free all memory associated with routing structures.
*/
void __exit ax25_rt_free(void)
{
ax25_route *s, *ax25_rt = ax25_route_list;
while (ax25_rt != NULL) {
s = ax25_rt;
ax25_rt = ax25_rt->next;
if (s->digipeat != NULL)
kfree(s->digipeat);
kfree(s);
}
}
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