1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
/*
* Spanning tree protocol; interface code
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <buytenh@gnu.org>
*
* $Id: br_stp_if.c,v 1.4 2001/04/14 21:14:39 davem Exp $
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/smp_lock.h>
#include <linux/etherdevice.h>
#include "br_private.h"
#include "br_private_stp.h"
/* Port id is composed of priority and port number.
* NB: least significant bits of priority are dropped to
* make room for more ports.
*/
static inline port_id br_make_port_id(__u8 priority, __u16 port_no)
{
return ((u16)priority << BR_PORT_BITS)
| (port_no & ((1<<BR_PORT_BITS)-1));
}
/* called under bridge lock */
void br_init_port(struct net_bridge_port *p)
{
p->port_id = br_make_port_id(p->priority, p->port_no);
br_become_designated_port(p);
p->state = BR_STATE_BLOCKING;
p->topology_change_ack = 0;
p->config_pending = 0;
br_stp_port_timer_init(p);
}
/* called under bridge lock */
void br_stp_enable_bridge(struct net_bridge *br)
{
struct net_bridge_port *p;
spin_lock_bh(&br->lock);
mod_timer(&br->hello_timer, jiffies + br->hello_time);
mod_timer(&br->gc_timer, jiffies + HZ/10);
br_config_bpdu_generation(br);
list_for_each_entry(p, &br->port_list, list) {
if ((p->dev->flags & IFF_UP) && netif_carrier_ok(p->dev))
br_stp_enable_port(p);
}
spin_unlock_bh(&br->lock);
}
/* NO locks held */
void br_stp_disable_bridge(struct net_bridge *br)
{
struct net_bridge_port *p;
spin_lock(&br->lock);
list_for_each_entry(p, &br->port_list, list) {
if (p->state != BR_STATE_DISABLED)
br_stp_disable_port(p);
}
br->topology_change = 0;
br->topology_change_detected = 0;
spin_unlock(&br->lock);
del_timer_sync(&br->hello_timer);
del_timer_sync(&br->topology_change_timer);
del_timer_sync(&br->tcn_timer);
del_timer_sync(&br->gc_timer);
}
/* called under bridge lock */
void br_stp_enable_port(struct net_bridge_port *p)
{
br_init_port(p);
br_port_state_selection(p->br);
}
/* called under bridge lock */
void br_stp_disable_port(struct net_bridge_port *p)
{
struct net_bridge *br;
int wasroot;
br = p->br;
printk(KERN_INFO "%s: port %i(%s) entering %s state\n",
br->dev->name, p->port_no, p->dev->name, "disabled");
wasroot = br_is_root_bridge(br);
br_become_designated_port(p);
p->state = BR_STATE_DISABLED;
p->topology_change_ack = 0;
p->config_pending = 0;
del_timer(&p->message_age_timer);
del_timer(&p->forward_delay_timer);
del_timer(&p->hold_timer);
br_configuration_update(br);
br_port_state_selection(br);
if (br_is_root_bridge(br) && !wasroot)
br_become_root_bridge(br);
}
/* called under bridge lock */
void br_stp_change_bridge_id(struct net_bridge *br, const unsigned char *addr)
{
unsigned char oldaddr[6];
struct net_bridge_port *p;
int wasroot;
wasroot = br_is_root_bridge(br);
memcpy(oldaddr, br->bridge_id.addr, ETH_ALEN);
memcpy(br->bridge_id.addr, addr, ETH_ALEN);
memcpy(br->dev->dev_addr, addr, ETH_ALEN);
list_for_each_entry(p, &br->port_list, list) {
if (!compare_ether_addr(p->designated_bridge.addr, oldaddr))
memcpy(p->designated_bridge.addr, addr, ETH_ALEN);
if (!compare_ether_addr(p->designated_root.addr, oldaddr))
memcpy(p->designated_root.addr, addr, ETH_ALEN);
}
br_configuration_update(br);
br_port_state_selection(br);
if (br_is_root_bridge(br) && !wasroot)
br_become_root_bridge(br);
}
static const unsigned char br_mac_zero[6];
/* called under bridge lock */
void br_stp_recalculate_bridge_id(struct net_bridge *br)
{
const unsigned char *addr = br_mac_zero;
struct net_bridge_port *p;
list_for_each_entry(p, &br->port_list, list) {
if (addr == br_mac_zero ||
compare_ether_addr(p->dev->dev_addr, addr) < 0)
addr = p->dev->dev_addr;
}
if (compare_ether_addr(br->bridge_id.addr, addr))
br_stp_change_bridge_id(br, addr);
}
/* called under bridge lock */
void br_stp_set_bridge_priority(struct net_bridge *br, u16 newprio)
{
struct net_bridge_port *p;
int wasroot;
wasroot = br_is_root_bridge(br);
list_for_each_entry(p, &br->port_list, list) {
if (p->state != BR_STATE_DISABLED &&
br_is_designated_port(p)) {
p->designated_bridge.prio[0] = (newprio >> 8) & 0xFF;
p->designated_bridge.prio[1] = newprio & 0xFF;
}
}
br->bridge_id.prio[0] = (newprio >> 8) & 0xFF;
br->bridge_id.prio[1] = newprio & 0xFF;
br_configuration_update(br);
br_port_state_selection(br);
if (br_is_root_bridge(br) && !wasroot)
br_become_root_bridge(br);
}
/* called under bridge lock */
void br_stp_set_port_priority(struct net_bridge_port *p, u8 newprio)
{
port_id new_port_id = br_make_port_id(newprio, p->port_no);
if (br_is_designated_port(p))
p->designated_port = new_port_id;
p->port_id = new_port_id;
p->priority = newprio;
if (!memcmp(&p->br->bridge_id, &p->designated_bridge, 8) &&
p->port_id < p->designated_port) {
br_become_designated_port(p);
br_port_state_selection(p->br);
}
}
/* called under bridge lock */
void br_stp_set_path_cost(struct net_bridge_port *p, u32 path_cost)
{
p->path_cost = path_cost;
br_configuration_update(p->br);
br_port_state_selection(p->br);
}
ssize_t br_show_bridge_id(char *buf, const struct bridge_id *id)
{
return sprintf(buf, "%.2x%.2x.%.2x%.2x%.2x%.2x%.2x%.2x\n",
id->prio[0], id->prio[1],
id->addr[0], id->addr[1], id->addr[2],
id->addr[3], id->addr[4], id->addr[5]);
}
|
