/*
|
/*
|
* Spanning tree protocol; BPDU handling
|
* Spanning tree protocol; BPDU handling
|
* Linux ethernet bridge
|
* Linux ethernet bridge
|
*
|
*
|
* Authors:
|
* Authors:
|
* Lennert Buytenhek <buytenh@gnu.org>
|
* Lennert Buytenhek <buytenh@gnu.org>
|
*
|
*
|
* $Id: br_stp_bpdu.c,v 1.1.1.1 2004-04-15 01:16:27 phoenix Exp $
|
* $Id: br_stp_bpdu.c,v 1.1.1.1 2004-04-15 01:16:27 phoenix Exp $
|
*
|
*
|
* This program is free software; you can redistribute it and/or
|
* This program is free software; you can redistribute it and/or
|
* modify it under the terms of the GNU General Public License
|
* modify it under the terms of the GNU General Public License
|
* as published by the Free Software Foundation; either version
|
* as published by the Free Software Foundation; either version
|
* 2 of the License, or (at your option) any later version.
|
* 2 of the License, or (at your option) any later version.
|
*/
|
*/
|
|
|
#include <linux/kernel.h>
|
#include <linux/kernel.h>
|
#include <linux/if_ether.h>
|
#include <linux/if_ether.h>
|
#include <linux/if_bridge.h>
|
#include <linux/if_bridge.h>
|
#include <linux/netfilter_bridge.h>
|
#include <linux/netfilter_bridge.h>
|
#include "br_private.h"
|
#include "br_private.h"
|
#include "br_private_stp.h"
|
#include "br_private_stp.h"
|
|
|
#define JIFFIES_TO_TICKS(j) (((j) << 8) / HZ)
|
#define JIFFIES_TO_TICKS(j) (((j) << 8) / HZ)
|
#define TICKS_TO_JIFFIES(j) (((j) * HZ) >> 8)
|
#define TICKS_TO_JIFFIES(j) (((j) * HZ) >> 8)
|
|
|
static void br_send_bpdu(struct net_bridge_port *p, unsigned char *data, int length)
|
static void br_send_bpdu(struct net_bridge_port *p, unsigned char *data, int length)
|
{
|
{
|
struct net_device *dev;
|
struct net_device *dev;
|
struct sk_buff *skb;
|
struct sk_buff *skb;
|
int size;
|
int size;
|
|
|
if (!p->br->stp_enabled)
|
if (!p->br->stp_enabled)
|
return;
|
return;
|
|
|
size = length + 2*ETH_ALEN + 2;
|
size = length + 2*ETH_ALEN + 2;
|
if (size < 60)
|
if (size < 60)
|
size = 60;
|
size = 60;
|
|
|
dev = p->dev;
|
dev = p->dev;
|
|
|
if ((skb = dev_alloc_skb(size)) == NULL) {
|
if ((skb = dev_alloc_skb(size)) == NULL) {
|
printk(KERN_INFO "br: memory squeeze!\n");
|
printk(KERN_INFO "br: memory squeeze!\n");
|
return;
|
return;
|
}
|
}
|
|
|
skb->dev = dev;
|
skb->dev = dev;
|
skb->protocol = htons(ETH_P_802_2);
|
skb->protocol = htons(ETH_P_802_2);
|
skb->mac.raw = skb_put(skb, size);
|
skb->mac.raw = skb_put(skb, size);
|
memcpy(skb->mac.raw, bridge_ula, ETH_ALEN);
|
memcpy(skb->mac.raw, bridge_ula, ETH_ALEN);
|
memcpy(skb->mac.raw+ETH_ALEN, dev->dev_addr, ETH_ALEN);
|
memcpy(skb->mac.raw+ETH_ALEN, dev->dev_addr, ETH_ALEN);
|
skb->mac.raw[2*ETH_ALEN] = 0;
|
skb->mac.raw[2*ETH_ALEN] = 0;
|
skb->mac.raw[2*ETH_ALEN+1] = length;
|
skb->mac.raw[2*ETH_ALEN+1] = length;
|
skb->nh.raw = skb->mac.raw + 2*ETH_ALEN + 2;
|
skb->nh.raw = skb->mac.raw + 2*ETH_ALEN + 2;
|
memcpy(skb->nh.raw, data, length);
|
memcpy(skb->nh.raw, data, length);
|
memset(skb->nh.raw + length, 0xa5, size - length - 2*ETH_ALEN - 2);
|
memset(skb->nh.raw + length, 0xa5, size - length - 2*ETH_ALEN - 2);
|
|
|
NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
|
NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
|
dev_queue_xmit);
|
dev_queue_xmit);
|
}
|
}
|
|
|
static __inline__ void br_set_ticks(unsigned char *dest, int jiff)
|
static __inline__ void br_set_ticks(unsigned char *dest, int jiff)
|
{
|
{
|
__u16 ticks;
|
__u16 ticks;
|
|
|
ticks = JIFFIES_TO_TICKS(jiff);
|
ticks = JIFFIES_TO_TICKS(jiff);
|
dest[0] = (ticks >> 8) & 0xFF;
|
dest[0] = (ticks >> 8) & 0xFF;
|
dest[1] = ticks & 0xFF;
|
dest[1] = ticks & 0xFF;
|
}
|
}
|
|
|
static __inline__ int br_get_ticks(unsigned char *dest)
|
static __inline__ int br_get_ticks(unsigned char *dest)
|
{
|
{
|
return TICKS_TO_JIFFIES((dest[0] << 8) | dest[1]);
|
return TICKS_TO_JIFFIES((dest[0] << 8) | dest[1]);
|
}
|
}
|
|
|
/* called under bridge lock */
|
/* called under bridge lock */
|
void br_send_config_bpdu(struct net_bridge_port *p, struct br_config_bpdu *bpdu)
|
void br_send_config_bpdu(struct net_bridge_port *p, struct br_config_bpdu *bpdu)
|
{
|
{
|
unsigned char buf[38];
|
unsigned char buf[38];
|
|
|
buf[0] = 0x42;
|
buf[0] = 0x42;
|
buf[1] = 0x42;
|
buf[1] = 0x42;
|
buf[2] = 0x03;
|
buf[2] = 0x03;
|
buf[3] = 0;
|
buf[3] = 0;
|
buf[4] = 0;
|
buf[4] = 0;
|
buf[5] = 0;
|
buf[5] = 0;
|
buf[6] = BPDU_TYPE_CONFIG;
|
buf[6] = BPDU_TYPE_CONFIG;
|
buf[7] = (bpdu->topology_change ? 0x01 : 0) |
|
buf[7] = (bpdu->topology_change ? 0x01 : 0) |
|
(bpdu->topology_change_ack ? 0x80 : 0);
|
(bpdu->topology_change_ack ? 0x80 : 0);
|
buf[8] = bpdu->root.prio[0];
|
buf[8] = bpdu->root.prio[0];
|
buf[9] = bpdu->root.prio[1];
|
buf[9] = bpdu->root.prio[1];
|
buf[10] = bpdu->root.addr[0];
|
buf[10] = bpdu->root.addr[0];
|
buf[11] = bpdu->root.addr[1];
|
buf[11] = bpdu->root.addr[1];
|
buf[12] = bpdu->root.addr[2];
|
buf[12] = bpdu->root.addr[2];
|
buf[13] = bpdu->root.addr[3];
|
buf[13] = bpdu->root.addr[3];
|
buf[14] = bpdu->root.addr[4];
|
buf[14] = bpdu->root.addr[4];
|
buf[15] = bpdu->root.addr[5];
|
buf[15] = bpdu->root.addr[5];
|
buf[16] = (bpdu->root_path_cost >> 24) & 0xFF;
|
buf[16] = (bpdu->root_path_cost >> 24) & 0xFF;
|
buf[17] = (bpdu->root_path_cost >> 16) & 0xFF;
|
buf[17] = (bpdu->root_path_cost >> 16) & 0xFF;
|
buf[18] = (bpdu->root_path_cost >> 8) & 0xFF;
|
buf[18] = (bpdu->root_path_cost >> 8) & 0xFF;
|
buf[19] = bpdu->root_path_cost & 0xFF;
|
buf[19] = bpdu->root_path_cost & 0xFF;
|
buf[20] = bpdu->bridge_id.prio[0];
|
buf[20] = bpdu->bridge_id.prio[0];
|
buf[21] = bpdu->bridge_id.prio[1];
|
buf[21] = bpdu->bridge_id.prio[1];
|
buf[22] = bpdu->bridge_id.addr[0];
|
buf[22] = bpdu->bridge_id.addr[0];
|
buf[23] = bpdu->bridge_id.addr[1];
|
buf[23] = bpdu->bridge_id.addr[1];
|
buf[24] = bpdu->bridge_id.addr[2];
|
buf[24] = bpdu->bridge_id.addr[2];
|
buf[25] = bpdu->bridge_id.addr[3];
|
buf[25] = bpdu->bridge_id.addr[3];
|
buf[26] = bpdu->bridge_id.addr[4];
|
buf[26] = bpdu->bridge_id.addr[4];
|
buf[27] = bpdu->bridge_id.addr[5];
|
buf[27] = bpdu->bridge_id.addr[5];
|
buf[28] = (bpdu->port_id >> 8) & 0xFF;
|
buf[28] = (bpdu->port_id >> 8) & 0xFF;
|
buf[29] = bpdu->port_id & 0xFF;
|
buf[29] = bpdu->port_id & 0xFF;
|
|
|
br_set_ticks(buf+30, bpdu->message_age);
|
br_set_ticks(buf+30, bpdu->message_age);
|
br_set_ticks(buf+32, bpdu->max_age);
|
br_set_ticks(buf+32, bpdu->max_age);
|
br_set_ticks(buf+34, bpdu->hello_time);
|
br_set_ticks(buf+34, bpdu->hello_time);
|
br_set_ticks(buf+36, bpdu->forward_delay);
|
br_set_ticks(buf+36, bpdu->forward_delay);
|
|
|
br_send_bpdu(p, buf, 38);
|
br_send_bpdu(p, buf, 38);
|
}
|
}
|
|
|
/* called under bridge lock */
|
/* called under bridge lock */
|
void br_send_tcn_bpdu(struct net_bridge_port *p)
|
void br_send_tcn_bpdu(struct net_bridge_port *p)
|
{
|
{
|
unsigned char buf[7];
|
unsigned char buf[7];
|
|
|
buf[0] = 0x42;
|
buf[0] = 0x42;
|
buf[1] = 0x42;
|
buf[1] = 0x42;
|
buf[2] = 0x03;
|
buf[2] = 0x03;
|
buf[3] = 0;
|
buf[3] = 0;
|
buf[4] = 0;
|
buf[4] = 0;
|
buf[5] = 0;
|
buf[5] = 0;
|
buf[6] = BPDU_TYPE_TCN;
|
buf[6] = BPDU_TYPE_TCN;
|
br_send_bpdu(p, buf, 7);
|
br_send_bpdu(p, buf, 7);
|
}
|
}
|
|
|
static unsigned char header[6] = {0x42, 0x42, 0x03, 0x00, 0x00, 0x00};
|
static unsigned char header[6] = {0x42, 0x42, 0x03, 0x00, 0x00, 0x00};
|
|
|
/* called under bridge lock */
|
/* called under bridge lock */
|
int br_stp_handle_bpdu(struct sk_buff *skb)
|
int br_stp_handle_bpdu(struct sk_buff *skb)
|
{
|
{
|
unsigned char *buf;
|
unsigned char *buf;
|
struct net_bridge_port *p;
|
struct net_bridge_port *p;
|
|
|
p = skb->dev->br_port;
|
p = skb->dev->br_port;
|
|
|
if (!p->br->stp_enabled ||
|
if (!p->br->stp_enabled ||
|
!pskb_may_pull(skb, sizeof(header)+1) ||
|
!pskb_may_pull(skb, sizeof(header)+1) ||
|
memcmp(skb->data, header, sizeof(header)))
|
memcmp(skb->data, header, sizeof(header)))
|
goto err;
|
goto err;
|
|
|
buf = skb_pull(skb, sizeof(header));
|
buf = skb_pull(skb, sizeof(header));
|
if (buf[0] == BPDU_TYPE_CONFIG) {
|
if (buf[0] == BPDU_TYPE_CONFIG) {
|
struct br_config_bpdu bpdu;
|
struct br_config_bpdu bpdu;
|
|
|
if (!pskb_may_pull(skb, 32))
|
if (!pskb_may_pull(skb, 32))
|
goto err;
|
goto err;
|
|
|
buf = skb->data;
|
buf = skb->data;
|
bpdu.topology_change = (buf[1] & 0x01) ? 1 : 0;
|
bpdu.topology_change = (buf[1] & 0x01) ? 1 : 0;
|
bpdu.topology_change_ack = (buf[1] & 0x80) ? 1 : 0;
|
bpdu.topology_change_ack = (buf[1] & 0x80) ? 1 : 0;
|
|
|
bpdu.root.prio[0] = buf[2];
|
bpdu.root.prio[0] = buf[2];
|
bpdu.root.prio[1] = buf[3];
|
bpdu.root.prio[1] = buf[3];
|
bpdu.root.addr[0] = buf[4];
|
bpdu.root.addr[0] = buf[4];
|
bpdu.root.addr[1] = buf[5];
|
bpdu.root.addr[1] = buf[5];
|
bpdu.root.addr[2] = buf[6];
|
bpdu.root.addr[2] = buf[6];
|
bpdu.root.addr[3] = buf[7];
|
bpdu.root.addr[3] = buf[7];
|
bpdu.root.addr[4] = buf[8];
|
bpdu.root.addr[4] = buf[8];
|
bpdu.root.addr[5] = buf[9];
|
bpdu.root.addr[5] = buf[9];
|
bpdu.root_path_cost =
|
bpdu.root_path_cost =
|
(buf[10] << 24) |
|
(buf[10] << 24) |
|
(buf[11] << 16) |
|
(buf[11] << 16) |
|
(buf[12] << 8) |
|
(buf[12] << 8) |
|
buf[13];
|
buf[13];
|
bpdu.bridge_id.prio[0] = buf[14];
|
bpdu.bridge_id.prio[0] = buf[14];
|
bpdu.bridge_id.prio[1] = buf[15];
|
bpdu.bridge_id.prio[1] = buf[15];
|
bpdu.bridge_id.addr[0] = buf[16];
|
bpdu.bridge_id.addr[0] = buf[16];
|
bpdu.bridge_id.addr[1] = buf[17];
|
bpdu.bridge_id.addr[1] = buf[17];
|
bpdu.bridge_id.addr[2] = buf[18];
|
bpdu.bridge_id.addr[2] = buf[18];
|
bpdu.bridge_id.addr[3] = buf[19];
|
bpdu.bridge_id.addr[3] = buf[19];
|
bpdu.bridge_id.addr[4] = buf[20];
|
bpdu.bridge_id.addr[4] = buf[20];
|
bpdu.bridge_id.addr[5] = buf[21];
|
bpdu.bridge_id.addr[5] = buf[21];
|
bpdu.port_id = (buf[22] << 8) | buf[23];
|
bpdu.port_id = (buf[22] << 8) | buf[23];
|
|
|
bpdu.message_age = br_get_ticks(buf+24);
|
bpdu.message_age = br_get_ticks(buf+24);
|
bpdu.max_age = br_get_ticks(buf+26);
|
bpdu.max_age = br_get_ticks(buf+26);
|
bpdu.hello_time = br_get_ticks(buf+28);
|
bpdu.hello_time = br_get_ticks(buf+28);
|
bpdu.forward_delay = br_get_ticks(buf+30);
|
bpdu.forward_delay = br_get_ticks(buf+30);
|
|
|
br_received_config_bpdu(p, &bpdu);
|
br_received_config_bpdu(p, &bpdu);
|
}
|
}
|
|
|
else if (buf[0] == BPDU_TYPE_TCN) {
|
else if (buf[0] == BPDU_TYPE_TCN) {
|
br_received_tcn_bpdu(p);
|
br_received_tcn_bpdu(p);
|
}
|
}
|
|
|
err:
|
err:
|
kfree_skb(skb);
|
kfree_skb(skb);
|
return 0;
|
return 0;
|
}
|
}
|
|
|
