linux/net/llc/llc_core.c
Eric W. Biederman 881d966b48 [NET]: Make the device list and device lookups per namespace.
This patch makes most of the generic device layer network
namespace safe.  This patch makes dev_base_head a
network namespace variable, and then it picks up
a few associated variables.  The functions:
dev_getbyhwaddr
dev_getfirsthwbytype
dev_get_by_flags
dev_get_by_name
__dev_get_by_name
dev_get_by_index
__dev_get_by_index
dev_ioctl
dev_ethtool
dev_load
wireless_process_ioctl

were modified to take a network namespace argument, and
deal with it.

vlan_ioctl_set and brioctl_set were modified so their
hooks will receive a network namespace argument.

So basically anthing in the core of the network stack that was
affected to by the change of dev_base was modified to handle
multiple network namespaces.  The rest of the network stack was
simply modified to explicitly use &init_net the initial network
namespace.  This can be fixed when those components of the network
stack are modified to handle multiple network namespaces.

For now the ifindex generator is left global.

Fundametally ifindex numbers are per namespace, or else
we will have corner case problems with migration when
we get that far.

At the same time there are assumptions in the network stack
that the ifindex of a network device won't change.  Making
the ifindex number global seems a good compromise until
the network stack can cope with ifindex changes when
you change namespaces, and the like.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:10 -07:00

197 lines
4.7 KiB
C

/*
* llc_core.c - Minimum needed routines for sap handling and module init/exit
*
* Copyright (c) 1997 by Procom Technology, Inc.
* 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
*
* This program can be redistributed or modified under the terms of the
* GNU General Public License as published by the Free Software Foundation.
* This program is distributed without any warranty or implied warranty
* of merchantability or fitness for a particular purpose.
*
* See the GNU General Public License for more details.
*/
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/if_ether.h>
#include <linux/netdevice.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/init.h>
#include <net/net_namespace.h>
#include <net/llc.h>
LIST_HEAD(llc_sap_list);
DEFINE_RWLOCK(llc_sap_list_lock);
unsigned char llc_station_mac_sa[ETH_ALEN];
/**
* llc_sap_alloc - allocates and initializes sap.
*
* Allocates and initializes sap.
*/
static struct llc_sap *llc_sap_alloc(void)
{
struct llc_sap *sap = kzalloc(sizeof(*sap), GFP_ATOMIC);
if (sap) {
sap->state = LLC_SAP_STATE_ACTIVE;
memcpy(sap->laddr.mac, llc_station_mac_sa, ETH_ALEN);
rwlock_init(&sap->sk_list.lock);
atomic_set(&sap->refcnt, 1);
}
return sap;
}
/**
* llc_add_sap - add sap to station list
* @sap: Address of the sap
*
* Adds a sap to the LLC's station sap list.
*/
static void llc_add_sap(struct llc_sap *sap)
{
list_add_tail(&sap->node, &llc_sap_list);
}
/**
* llc_del_sap - del sap from station list
* @sap: Address of the sap
*
* Removes a sap to the LLC's station sap list.
*/
static void llc_del_sap(struct llc_sap *sap)
{
write_lock_bh(&llc_sap_list_lock);
list_del(&sap->node);
write_unlock_bh(&llc_sap_list_lock);
}
static struct llc_sap *__llc_sap_find(unsigned char sap_value)
{
struct llc_sap* sap;
list_for_each_entry(sap, &llc_sap_list, node)
if (sap->laddr.lsap == sap_value)
goto out;
sap = NULL;
out:
return sap;
}
/**
* llc_sap_find - searchs a SAP in station
* @sap_value: sap to be found
*
* Searchs for a sap in the sap list of the LLC's station upon the sap ID.
* If the sap is found it will be refcounted and the user will have to do
* a llc_sap_put after use.
* Returns the sap or %NULL if not found.
*/
struct llc_sap *llc_sap_find(unsigned char sap_value)
{
struct llc_sap* sap;
read_lock_bh(&llc_sap_list_lock);
sap = __llc_sap_find(sap_value);
if (sap)
llc_sap_hold(sap);
read_unlock_bh(&llc_sap_list_lock);
return sap;
}
/**
* llc_sap_open - open interface to the upper layers.
* @lsap: SAP number.
* @func: rcv func for datalink protos
*
* Interface function to upper layer. Each one who wants to get a SAP
* (for example NetBEUI) should call this function. Returns the opened
* SAP for success, NULL for failure.
*/
struct llc_sap *llc_sap_open(unsigned char lsap,
int (*func)(struct sk_buff *skb,
struct net_device *dev,
struct packet_type *pt,
struct net_device *orig_dev))
{
struct llc_sap *sap = NULL;
write_lock_bh(&llc_sap_list_lock);
if (__llc_sap_find(lsap)) /* SAP already exists */
goto out;
sap = llc_sap_alloc();
if (!sap)
goto out;
sap->laddr.lsap = lsap;
sap->rcv_func = func;
llc_add_sap(sap);
out:
write_unlock_bh(&llc_sap_list_lock);
return sap;
}
/**
* llc_sap_close - close interface for upper layers.
* @sap: SAP to be closed.
*
* Close interface function to upper layer. Each one who wants to
* close an open SAP (for example NetBEUI) should call this function.
* Removes this sap from the list of saps in the station and then
* frees the memory for this sap.
*/
void llc_sap_close(struct llc_sap *sap)
{
WARN_ON(!hlist_empty(&sap->sk_list.list));
llc_del_sap(sap);
kfree(sap);
}
static struct packet_type llc_packet_type = {
.type = __constant_htons(ETH_P_802_2),
.func = llc_rcv,
};
static struct packet_type llc_tr_packet_type = {
.type = __constant_htons(ETH_P_TR_802_2),
.func = llc_rcv,
};
static int __init llc_init(void)
{
struct net_device *dev;
dev = first_net_device(&init_net);
if (dev != NULL)
dev = next_net_device(dev);
if (dev != NULL)
memcpy(llc_station_mac_sa, dev->dev_addr, ETH_ALEN);
else
memset(llc_station_mac_sa, 0, ETH_ALEN);
dev_add_pack(&llc_packet_type);
dev_add_pack(&llc_tr_packet_type);
return 0;
}
static void __exit llc_exit(void)
{
dev_remove_pack(&llc_packet_type);
dev_remove_pack(&llc_tr_packet_type);
}
module_init(llc_init);
module_exit(llc_exit);
EXPORT_SYMBOL(llc_station_mac_sa);
EXPORT_SYMBOL(llc_sap_list);
EXPORT_SYMBOL(llc_sap_list_lock);
EXPORT_SYMBOL(llc_sap_find);
EXPORT_SYMBOL(llc_sap_open);
EXPORT_SYMBOL(llc_sap_close);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003");
MODULE_DESCRIPTION("LLC IEEE 802.2 core support");