linux/net/bridge/br_private.h
Simon Wunderlich 4adf0af681 bridge: send correct MTU value in PMTU (revised)
When bridging interfaces with different MTUs, the bridge correctly chooses
the minimum of the MTUs of the physical devices as the bridges MTU.  But
when a frame is passed which fits through the incoming, but not through
the outgoing interface, a "Fragmentation Needed" packet is generated.

However, the propagated MTU is hardcoded to 1500, which is wrong in this
situation.  The sender will repeat the packet again with the same frame
size, and the same problem will occur again.

Instead of sending 1500, the (correct) MTU value of the bridge is now sent
via PMTU.  To achieve this, the corresponding rtable structure is stored
in its net_bridge structure.

Modified to get rid of fake_net_device as well.

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-30 16:27:55 -07:00

272 lines
7.8 KiB
C

/*
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <buytenh@gnu.org>
*
* This program 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.
*/
#ifndef _BR_PRIVATE_H
#define _BR_PRIVATE_H
#include <linux/netdevice.h>
#include <linux/if_bridge.h>
#include <net/route.h>
#define BR_HASH_BITS 8
#define BR_HASH_SIZE (1 << BR_HASH_BITS)
#define BR_HOLD_TIME (1*HZ)
#define BR_PORT_BITS 10
#define BR_MAX_PORTS (1<<BR_PORT_BITS)
#define BR_VERSION "2.3"
/* Path to usermode spanning tree program */
#define BR_STP_PROG "/sbin/bridge-stp"
typedef struct bridge_id bridge_id;
typedef struct mac_addr mac_addr;
typedef __u16 port_id;
struct bridge_id
{
unsigned char prio[2];
unsigned char addr[6];
};
struct mac_addr
{
unsigned char addr[6];
};
struct net_bridge_fdb_entry
{
struct hlist_node hlist;
struct net_bridge_port *dst;
struct rcu_head rcu;
atomic_t use_count;
unsigned long ageing_timer;
mac_addr addr;
unsigned char is_local;
unsigned char is_static;
};
struct net_bridge_port
{
struct net_bridge *br;
struct net_device *dev;
struct list_head list;
/* STP */
u8 priority;
u8 state;
u16 port_no;
unsigned char topology_change_ack;
unsigned char config_pending;
port_id port_id;
port_id designated_port;
bridge_id designated_root;
bridge_id designated_bridge;
u32 path_cost;
u32 designated_cost;
struct timer_list forward_delay_timer;
struct timer_list hold_timer;
struct timer_list message_age_timer;
struct kobject kobj;
struct rcu_head rcu;
};
struct net_bridge
{
spinlock_t lock;
struct list_head port_list;
struct net_device *dev;
spinlock_t hash_lock;
struct hlist_head hash[BR_HASH_SIZE];
struct list_head age_list;
unsigned long feature_mask;
#ifdef CONFIG_BRIDGE_NETFILTER
struct rtable fake_rtable;
#endif
unsigned long flags;
#define BR_SET_MAC_ADDR 0x00000001
/* STP */
bridge_id designated_root;
bridge_id bridge_id;
u32 root_path_cost;
unsigned long max_age;
unsigned long hello_time;
unsigned long forward_delay;
unsigned long bridge_max_age;
unsigned long ageing_time;
unsigned long bridge_hello_time;
unsigned long bridge_forward_delay;
u8 group_addr[ETH_ALEN];
u16 root_port;
enum {
BR_NO_STP, /* no spanning tree */
BR_KERNEL_STP, /* old STP in kernel */
BR_USER_STP, /* new RSTP in userspace */
} stp_enabled;
unsigned char topology_change;
unsigned char topology_change_detected;
struct timer_list hello_timer;
struct timer_list tcn_timer;
struct timer_list topology_change_timer;
struct timer_list gc_timer;
struct kobject *ifobj;
};
extern struct notifier_block br_device_notifier;
extern const u8 br_group_address[ETH_ALEN];
/* called under bridge lock */
static inline int br_is_root_bridge(const struct net_bridge *br)
{
return !memcmp(&br->bridge_id, &br->designated_root, 8);
}
/* br_device.c */
extern void br_dev_setup(struct net_device *dev);
extern int br_dev_xmit(struct sk_buff *skb, struct net_device *dev);
/* br_fdb.c */
extern int br_fdb_init(void);
extern void br_fdb_fini(void);
extern void br_fdb_flush(struct net_bridge *br);
extern void br_fdb_changeaddr(struct net_bridge_port *p,
const unsigned char *newaddr);
extern void br_fdb_cleanup(unsigned long arg);
extern void br_fdb_delete_by_port(struct net_bridge *br,
const struct net_bridge_port *p, int do_all);
extern struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br,
const unsigned char *addr);
extern struct net_bridge_fdb_entry *br_fdb_get(struct net_bridge *br,
unsigned char *addr);
extern void br_fdb_put(struct net_bridge_fdb_entry *ent);
extern int br_fdb_fillbuf(struct net_bridge *br, void *buf,
unsigned long count, unsigned long off);
extern int br_fdb_insert(struct net_bridge *br,
struct net_bridge_port *source,
const unsigned char *addr);
extern void br_fdb_update(struct net_bridge *br,
struct net_bridge_port *source,
const unsigned char *addr);
/* br_forward.c */
extern void br_deliver(const struct net_bridge_port *to,
struct sk_buff *skb);
extern int br_dev_queue_push_xmit(struct sk_buff *skb);
extern void br_forward(const struct net_bridge_port *to,
struct sk_buff *skb);
extern int br_forward_finish(struct sk_buff *skb);
extern void br_flood_deliver(struct net_bridge *br, struct sk_buff *skb);
extern void br_flood_forward(struct net_bridge *br, struct sk_buff *skb);
/* br_if.c */
extern void br_port_carrier_check(struct net_bridge_port *p);
extern int br_add_bridge(const char *name);
extern int br_del_bridge(const char *name);
extern void br_cleanup_bridges(void);
extern int br_add_if(struct net_bridge *br,
struct net_device *dev);
extern int br_del_if(struct net_bridge *br,
struct net_device *dev);
extern int br_min_mtu(const struct net_bridge *br);
extern void br_features_recompute(struct net_bridge *br);
/* br_input.c */
extern int br_handle_frame_finish(struct sk_buff *skb);
extern struct sk_buff *br_handle_frame(struct net_bridge_port *p,
struct sk_buff *skb);
/* br_ioctl.c */
extern int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);
extern int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd, void __user *arg);
/* br_netfilter.c */
#ifdef CONFIG_BRIDGE_NETFILTER
extern int br_netfilter_init(void);
extern void br_netfilter_fini(void);
extern void br_netfilter_rtable_init(struct net_bridge *);
#else
#define br_netfilter_init() (0)
#define br_netfilter_fini() do { } while(0)
#define br_netfilter_rtable_init(x)
#endif
/* br_stp.c */
extern void br_log_state(const struct net_bridge_port *p);
extern struct net_bridge_port *br_get_port(struct net_bridge *br,
u16 port_no);
extern void br_init_port(struct net_bridge_port *p);
extern void br_become_designated_port(struct net_bridge_port *p);
/* br_stp_if.c */
extern void br_stp_enable_bridge(struct net_bridge *br);
extern void br_stp_disable_bridge(struct net_bridge *br);
extern void br_stp_set_enabled(struct net_bridge *br, unsigned long val);
extern void br_stp_enable_port(struct net_bridge_port *p);
extern void br_stp_disable_port(struct net_bridge_port *p);
extern void br_stp_recalculate_bridge_id(struct net_bridge *br);
extern void br_stp_change_bridge_id(struct net_bridge *br, const unsigned char *a);
extern void br_stp_set_bridge_priority(struct net_bridge *br,
u16 newprio);
extern void br_stp_set_port_priority(struct net_bridge_port *p,
u8 newprio);
extern void br_stp_set_path_cost(struct net_bridge_port *p,
u32 path_cost);
extern ssize_t br_show_bridge_id(char *buf, const struct bridge_id *id);
/* br_stp_bpdu.c */
struct stp_proto;
extern void br_stp_rcv(const struct stp_proto *proto, struct sk_buff *skb,
struct net_device *dev);
/* br_stp_timer.c */
extern void br_stp_timer_init(struct net_bridge *br);
extern void br_stp_port_timer_init(struct net_bridge_port *p);
extern unsigned long br_timer_value(const struct timer_list *timer);
/* br.c */
extern struct net_bridge_fdb_entry *(*br_fdb_get_hook)(struct net_bridge *br,
unsigned char *addr);
extern void (*br_fdb_put_hook)(struct net_bridge_fdb_entry *ent);
/* br_netlink.c */
extern int br_netlink_init(void);
extern void br_netlink_fini(void);
extern void br_ifinfo_notify(int event, struct net_bridge_port *port);
#ifdef CONFIG_SYSFS
/* br_sysfs_if.c */
extern struct sysfs_ops brport_sysfs_ops;
extern int br_sysfs_addif(struct net_bridge_port *p);
/* br_sysfs_br.c */
extern int br_sysfs_addbr(struct net_device *dev);
extern void br_sysfs_delbr(struct net_device *dev);
#else
#define br_sysfs_addif(p) (0)
#define br_sysfs_addbr(dev) (0)
#define br_sysfs_delbr(dev) do { } while(0)
#endif /* CONFIG_SYSFS */
#endif