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linux/net/bridge/br_private_stp.h
stephen hemminger 14f98f258f bridge: range check STP parameters
Apply restrictions on STP parameters based 802.1D 1998 standard.
   * Fixes missing locking in set path cost ioctl
   * Uses common code for both ioctl and sysfs

This is based on an earlier patch Sasikanth V but with overhaul.

Note:
1. It does NOT enforce the restriction on the relationship max_age and
   forward delay or hello time because in existing implementation these are
   set as independant operations.

2. If STP is disabled, there is no restriction on forward delay

3. No restriction on holding time because users use Linux code to act
   as hub or be sticky.

4. Although standard allow 0-255, Linux only allows 0-63 for port priority
   because more bits are reserved for port number.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-04 17:22:29 -07:00

70 lines
1.9 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_STP_H
#define _BR_PRIVATE_STP_H
#define BPDU_TYPE_CONFIG 0
#define BPDU_TYPE_TCN 0x80
/* IEEE 802.1D-1998 timer values */
#define BR_MIN_HELLO_TIME (1*HZ)
#define BR_MAX_HELLO_TIME (10*HZ)
#define BR_MIN_FORWARD_DELAY (2*HZ)
#define BR_MAX_FORWARD_DELAY (30*HZ)
#define BR_MIN_MAX_AGE (6*HZ)
#define BR_MAX_MAX_AGE (40*HZ)
#define BR_MIN_PATH_COST 1
#define BR_MAX_PATH_COST 65535
struct br_config_bpdu
{
unsigned topology_change:1;
unsigned topology_change_ack:1;
bridge_id root;
int root_path_cost;
bridge_id bridge_id;
port_id port_id;
int message_age;
int max_age;
int hello_time;
int forward_delay;
};
/* called under bridge lock */
static inline int br_is_designated_port(const struct net_bridge_port *p)
{
return !memcmp(&p->designated_bridge, &p->br->bridge_id, 8) &&
(p->designated_port == p->port_id);
}
/* br_stp.c */
extern void br_become_root_bridge(struct net_bridge *br);
extern void br_config_bpdu_generation(struct net_bridge *);
extern void br_configuration_update(struct net_bridge *);
extern void br_port_state_selection(struct net_bridge *);
extern void br_received_config_bpdu(struct net_bridge_port *p, struct br_config_bpdu *bpdu);
extern void br_received_tcn_bpdu(struct net_bridge_port *p);
extern void br_transmit_config(struct net_bridge_port *p);
extern void br_transmit_tcn(struct net_bridge *br);
extern void br_topology_change_detection(struct net_bridge *br);
/* br_stp_bpdu.c */
extern void br_send_config_bpdu(struct net_bridge_port *, struct br_config_bpdu *);
extern void br_send_tcn_bpdu(struct net_bridge_port *);
#endif