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git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - net/bridge/br_stp_if.c
2 * Spanning tree protocol; interface code
3 * Linux ethernet bridge
6 * Lennert Buytenhek <buytenh@gnu.org>
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
14 #include <linux/kernel.h>
15 #include <linux/etherdevice.h>
16 #include <linux/rtnetlink.h>
18 #include "br_private.h"
19 #include "br_private_stp.h"
22 /* Port id is composed of priority and port number.
23 * NB: least significant bits of priority are dropped to
24 * make room for more ports.
26 static inline port_id
br_make_port_id(__u8 priority
, __u16 port_no
)
28 return ((u16
)priority
<< BR_PORT_BITS
)
29 | (port_no
& ((1<<BR_PORT_BITS
)-1));
32 /* called under bridge lock */
33 void br_init_port(struct net_bridge_port
*p
)
35 p
->port_id
= br_make_port_id(p
->priority
, p
->port_no
);
36 br_become_designated_port(p
);
37 p
->state
= BR_STATE_BLOCKING
;
38 p
->topology_change_ack
= 0;
39 p
->config_pending
= 0;
42 /* called under bridge lock */
43 void br_stp_enable_bridge(struct net_bridge
*br
)
45 struct net_bridge_port
*p
;
47 spin_lock_bh(&br
->lock
);
48 mod_timer(&br
->hello_timer
, jiffies
+ br
->hello_time
);
49 mod_timer(&br
->gc_timer
, jiffies
+ HZ
/10);
51 br_config_bpdu_generation(br
);
53 list_for_each_entry(p
, &br
->port_list
, list
) {
54 if ((p
->dev
->flags
& IFF_UP
) && netif_carrier_ok(p
->dev
))
55 br_stp_enable_port(p
);
58 spin_unlock_bh(&br
->lock
);
62 void br_stp_disable_bridge(struct net_bridge
*br
)
64 struct net_bridge_port
*p
;
66 spin_lock_bh(&br
->lock
);
67 list_for_each_entry(p
, &br
->port_list
, list
) {
68 if (p
->state
!= BR_STATE_DISABLED
)
69 br_stp_disable_port(p
);
73 br
->topology_change
= 0;
74 br
->topology_change_detected
= 0;
75 spin_unlock_bh(&br
->lock
);
77 del_timer_sync(&br
->hello_timer
);
78 del_timer_sync(&br
->topology_change_timer
);
79 del_timer_sync(&br
->tcn_timer
);
80 del_timer_sync(&br
->gc_timer
);
83 /* called under bridge lock */
84 void br_stp_enable_port(struct net_bridge_port
*p
)
87 br_port_state_selection(p
->br
);
91 /* called under bridge lock */
92 void br_stp_disable_port(struct net_bridge_port
*p
)
94 struct net_bridge
*br
= p
->br
;
99 wasroot
= br_is_root_bridge(br
);
100 br_become_designated_port(p
);
101 p
->state
= BR_STATE_DISABLED
;
102 p
->topology_change_ack
= 0;
103 p
->config_pending
= 0;
105 del_timer(&p
->message_age_timer
);
106 del_timer(&p
->forward_delay_timer
);
107 del_timer(&p
->hold_timer
);
109 br_fdb_delete_by_port(br
, p
, 0);
110 br_multicast_disable_port(p
);
112 br_configuration_update(br
);
114 br_port_state_selection(br
);
116 if (br_is_root_bridge(br
) && !wasroot
)
117 br_become_root_bridge(br
);
120 static void br_stp_start(struct net_bridge
*br
)
123 char *argv
[] = { BR_STP_PROG
, br
->dev
->name
, "start", NULL
};
124 char *envp
[] = { NULL
};
126 r
= call_usermodehelper(BR_STP_PROG
, argv
, envp
, UMH_WAIT_PROC
);
128 br
->stp_enabled
= BR_USER_STP
;
129 br_debug(br
, "userspace STP started\n");
131 br
->stp_enabled
= BR_KERNEL_STP
;
132 br_debug(br
, "using kernel STP\n");
134 /* To start timers on any ports left in blocking */
135 spin_lock_bh(&br
->lock
);
136 br_port_state_selection(br
);
137 spin_unlock_bh(&br
->lock
);
141 static void br_stp_stop(struct net_bridge
*br
)
144 char *argv
[] = { BR_STP_PROG
, br
->dev
->name
, "stop", NULL
};
145 char *envp
[] = { NULL
};
147 if (br
->stp_enabled
== BR_USER_STP
) {
148 r
= call_usermodehelper(BR_STP_PROG
, argv
, envp
, 1);
149 br_info(br
, "userspace STP stopped, return code %d\n", r
);
151 /* To start timers on any ports left in blocking */
152 spin_lock_bh(&br
->lock
);
153 br_port_state_selection(br
);
154 spin_unlock_bh(&br
->lock
);
157 br
->stp_enabled
= BR_NO_STP
;
160 void br_stp_set_enabled(struct net_bridge
*br
, unsigned long val
)
165 if (br
->stp_enabled
== BR_NO_STP
)
168 if (br
->stp_enabled
!= BR_NO_STP
)
173 /* called under bridge lock */
174 void br_stp_change_bridge_id(struct net_bridge
*br
, const unsigned char *addr
)
176 /* should be aligned on 2 bytes for compare_ether_addr() */
177 unsigned short oldaddr_aligned
[ETH_ALEN
>> 1];
178 unsigned char *oldaddr
= (unsigned char *)oldaddr_aligned
;
179 struct net_bridge_port
*p
;
182 wasroot
= br_is_root_bridge(br
);
184 memcpy(oldaddr
, br
->bridge_id
.addr
, ETH_ALEN
);
185 memcpy(br
->bridge_id
.addr
, addr
, ETH_ALEN
);
186 memcpy(br
->dev
->dev_addr
, addr
, ETH_ALEN
);
188 list_for_each_entry(p
, &br
->port_list
, list
) {
189 if (!compare_ether_addr(p
->designated_bridge
.addr
, oldaddr
))
190 memcpy(p
->designated_bridge
.addr
, addr
, ETH_ALEN
);
192 if (!compare_ether_addr(p
->designated_root
.addr
, oldaddr
))
193 memcpy(p
->designated_root
.addr
, addr
, ETH_ALEN
);
197 br_configuration_update(br
);
198 br_port_state_selection(br
);
199 if (br_is_root_bridge(br
) && !wasroot
)
200 br_become_root_bridge(br
);
203 /* should be aligned on 2 bytes for compare_ether_addr() */
204 static const unsigned short br_mac_zero_aligned
[ETH_ALEN
>> 1];
206 /* called under bridge lock */
207 void br_stp_recalculate_bridge_id(struct net_bridge
*br
)
209 const unsigned char *br_mac_zero
=
210 (const unsigned char *)br_mac_zero_aligned
;
211 const unsigned char *addr
= br_mac_zero
;
212 struct net_bridge_port
*p
;
214 /* user has chosen a value so keep it */
215 if (br
->flags
& BR_SET_MAC_ADDR
)
218 list_for_each_entry(p
, &br
->port_list
, list
) {
219 if (addr
== br_mac_zero
||
220 memcmp(p
->dev
->dev_addr
, addr
, ETH_ALEN
) < 0)
221 addr
= p
->dev
->dev_addr
;
225 if (compare_ether_addr(br
->bridge_id
.addr
, addr
))
226 br_stp_change_bridge_id(br
, addr
);
229 /* called under bridge lock */
230 void br_stp_set_bridge_priority(struct net_bridge
*br
, u16 newprio
)
232 struct net_bridge_port
*p
;
235 wasroot
= br_is_root_bridge(br
);
237 list_for_each_entry(p
, &br
->port_list
, list
) {
238 if (p
->state
!= BR_STATE_DISABLED
&&
239 br_is_designated_port(p
)) {
240 p
->designated_bridge
.prio
[0] = (newprio
>> 8) & 0xFF;
241 p
->designated_bridge
.prio
[1] = newprio
& 0xFF;
246 br
->bridge_id
.prio
[0] = (newprio
>> 8) & 0xFF;
247 br
->bridge_id
.prio
[1] = newprio
& 0xFF;
248 br_configuration_update(br
);
249 br_port_state_selection(br
);
250 if (br_is_root_bridge(br
) && !wasroot
)
251 br_become_root_bridge(br
);
254 /* called under bridge lock */
255 void br_stp_set_port_priority(struct net_bridge_port
*p
, u8 newprio
)
257 port_id new_port_id
= br_make_port_id(newprio
, p
->port_no
);
259 if (br_is_designated_port(p
))
260 p
->designated_port
= new_port_id
;
262 p
->port_id
= new_port_id
;
263 p
->priority
= newprio
;
264 if (!memcmp(&p
->br
->bridge_id
, &p
->designated_bridge
, 8) &&
265 p
->port_id
< p
->designated_port
) {
266 br_become_designated_port(p
);
267 br_port_state_selection(p
->br
);
271 /* called under bridge lock */
272 void br_stp_set_path_cost(struct net_bridge_port
*p
, u32 path_cost
)
274 p
->path_cost
= path_cost
;
275 br_configuration_update(p
->br
);
276 br_port_state_selection(p
->br
);
279 ssize_t
br_show_bridge_id(char *buf
, const struct bridge_id
*id
)
281 return sprintf(buf
, "%.2x%.2x.%.2x%.2x%.2x%.2x%.2x%.2x\n",
282 id
->prio
[0], id
->prio
[1],
283 id
->addr
[0], id
->addr
[1], id
->addr
[2],
284 id
->addr
[3], id
->addr
[4], id
->addr
[5]);