linux/net/x25/x25_forward.c
Thomas Gleixner ee5d8f4d89 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 41
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 18 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170858.008906948@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:12 +02:00

166 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* History
* 03-01-2007 Added forwarding for x.25 Andrew Hendry
*/
#define pr_fmt(fmt) "X25: " fmt
#include <linux/if_arp.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <net/x25.h>
LIST_HEAD(x25_forward_list);
DEFINE_RWLOCK(x25_forward_list_lock);
int x25_forward_call(struct x25_address *dest_addr, struct x25_neigh *from,
struct sk_buff *skb, int lci)
{
struct x25_route *rt;
struct x25_neigh *neigh_new = NULL;
struct list_head *entry;
struct x25_forward *x25_frwd, *new_frwd;
struct sk_buff *skbn;
short same_lci = 0;
int rc = 0;
if ((rt = x25_get_route(dest_addr)) == NULL)
goto out_no_route;
if ((neigh_new = x25_get_neigh(rt->dev)) == NULL) {
/* This shouldn't happen, if it occurs somehow
* do something sensible
*/
goto out_put_route;
}
/* Avoid a loop. This is the normal exit path for a
* system with only one x.25 iface and default route
*/
if (rt->dev == from->dev) {
goto out_put_nb;
}
/* Remote end sending a call request on an already
* established LCI? It shouldn't happen, just in case..
*/
read_lock_bh(&x25_forward_list_lock);
list_for_each(entry, &x25_forward_list) {
x25_frwd = list_entry(entry, struct x25_forward, node);
if (x25_frwd->lci == lci) {
pr_warn("call request for lci which is already registered!, transmitting but not registering new pair\n");
same_lci = 1;
}
}
read_unlock_bh(&x25_forward_list_lock);
/* Save the forwarding details for future traffic */
if (!same_lci){
if ((new_frwd = kmalloc(sizeof(struct x25_forward),
GFP_ATOMIC)) == NULL){
rc = -ENOMEM;
goto out_put_nb;
}
new_frwd->lci = lci;
new_frwd->dev1 = rt->dev;
new_frwd->dev2 = from->dev;
write_lock_bh(&x25_forward_list_lock);
list_add(&new_frwd->node, &x25_forward_list);
write_unlock_bh(&x25_forward_list_lock);
}
/* Forward the call request */
if ( (skbn = skb_clone(skb, GFP_ATOMIC)) == NULL){
goto out_put_nb;
}
x25_transmit_link(skbn, neigh_new);
rc = 1;
out_put_nb:
x25_neigh_put(neigh_new);
out_put_route:
x25_route_put(rt);
out_no_route:
return rc;
}
int x25_forward_data(int lci, struct x25_neigh *from, struct sk_buff *skb) {
struct x25_forward *frwd;
struct list_head *entry;
struct net_device *peer = NULL;
struct x25_neigh *nb;
struct sk_buff *skbn;
int rc = 0;
read_lock_bh(&x25_forward_list_lock);
list_for_each(entry, &x25_forward_list) {
frwd = list_entry(entry, struct x25_forward, node);
if (frwd->lci == lci) {
/* The call is established, either side can send */
if (from->dev == frwd->dev1) {
peer = frwd->dev2;
} else {
peer = frwd->dev1;
}
break;
}
}
read_unlock_bh(&x25_forward_list_lock);
if ( (nb = x25_get_neigh(peer)) == NULL)
goto out;
if ( (skbn = pskb_copy(skb, GFP_ATOMIC)) == NULL){
goto output;
}
x25_transmit_link(skbn, nb);
rc = 1;
output:
x25_neigh_put(nb);
out:
return rc;
}
void x25_clear_forward_by_lci(unsigned int lci)
{
struct x25_forward *fwd;
struct list_head *entry, *tmp;
write_lock_bh(&x25_forward_list_lock);
list_for_each_safe(entry, tmp, &x25_forward_list) {
fwd = list_entry(entry, struct x25_forward, node);
if (fwd->lci == lci) {
list_del(&fwd->node);
kfree(fwd);
}
}
write_unlock_bh(&x25_forward_list_lock);
}
void x25_clear_forward_by_dev(struct net_device *dev)
{
struct x25_forward *fwd;
struct list_head *entry, *tmp;
write_lock_bh(&x25_forward_list_lock);
list_for_each_safe(entry, tmp, &x25_forward_list) {
fwd = list_entry(entry, struct x25_forward, node);
if ((fwd->dev1 == dev) || (fwd->dev2 == dev)){
list_del(&fwd->node);
kfree(fwd);
}
}
write_unlock_bh(&x25_forward_list_lock);
}