Commit | Line | Data |
---|---|---|
2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /* |
3 | * Spanning tree protocol; interface code | |
4 | * Linux ethernet bridge | |
5 | * | |
6 | * Authors: | |
7 | * Lennert Buytenhek <buytenh@gnu.org> | |
1da177e4 LT |
8 | */ |
9 | ||
10 | #include <linux/kernel.h> | |
79bb1ee4 | 11 | #include <linux/kmod.h> |
6ede2463 | 12 | #include <linux/etherdevice.h> |
11dc1f36 | 13 | #include <linux/rtnetlink.h> |
6ac311ae | 14 | #include <net/switchdev.h> |
1da177e4 LT |
15 | |
16 | #include "br_private.h" | |
17 | #include "br_private_stp.h" | |
18 | ||
19 | ||
20 | /* Port id is composed of priority and port number. | |
14f98f25 | 21 | * NB: some bits of priority are dropped to |
1da177e4 LT |
22 | * make room for more ports. |
23 | */ | |
24 | static inline port_id br_make_port_id(__u8 priority, __u16 port_no) | |
25 | { | |
9d6f229f | 26 | return ((u16)priority << BR_PORT_BITS) |
1da177e4 LT |
27 | | (port_no & ((1<<BR_PORT_BITS)-1)); |
28 | } | |
29 | ||
14f98f25 | 30 | #define BR_MAX_PORT_PRIORITY ((u16)~0 >> BR_PORT_BITS) |
31 | ||
1da177e4 LT |
32 | /* called under bridge lock */ |
33 | void br_init_port(struct net_bridge_port *p) | |
34 | { | |
6ac311ae ER |
35 | int err; |
36 | ||
1da177e4 LT |
37 | p->port_id = br_make_port_id(p->priority, p->port_no); |
38 | br_become_designated_port(p); | |
775dd692 | 39 | br_set_state(p, BR_STATE_BLOCKING); |
1da177e4 LT |
40 | p->topology_change_ack = 0; |
41 | p->config_pending = 0; | |
6ac311ae | 42 | |
82dd4332 VD |
43 | err = __set_ageing_time(p->dev, p->br->ageing_time); |
44 | if (err) | |
45 | netdev_err(p->dev, "failed to offload ageing time\n"); | |
1da177e4 LT |
46 | } |
47 | ||
dba479f3 | 48 | /* NO locks held */ |
1da177e4 LT |
49 | void br_stp_enable_bridge(struct net_bridge *br) |
50 | { | |
51 | struct net_bridge_port *p; | |
52 | ||
53 | spin_lock_bh(&br->lock); | |
76b91c32 NA |
54 | if (br->stp_enabled == BR_KERNEL_STP) |
55 | mod_timer(&br->hello_timer, jiffies + br->hello_time); | |
f7cdee8a | 56 | mod_delayed_work(system_long_wq, &br->gc_work, HZ / 10); |
9d6f229f | 57 | |
1da177e4 LT |
58 | br_config_bpdu_generation(br); |
59 | ||
60 | list_for_each_entry(p, &br->port_list, list) { | |
576eb625 | 61 | if (netif_running(p->dev) && netif_oper_up(p->dev)) |
1da177e4 LT |
62 | br_stp_enable_port(p); |
63 | ||
64 | } | |
65 | spin_unlock_bh(&br->lock); | |
66 | } | |
67 | ||
68 | /* NO locks held */ | |
69 | void br_stp_disable_bridge(struct net_bridge *br) | |
70 | { | |
71 | struct net_bridge_port *p; | |
72 | ||
78872ccb | 73 | spin_lock_bh(&br->lock); |
1da177e4 LT |
74 | list_for_each_entry(p, &br->port_list, list) { |
75 | if (p->state != BR_STATE_DISABLED) | |
76 | br_stp_disable_port(p); | |
77 | ||
78 | } | |
79 | ||
8384b5f5 | 80 | __br_set_topology_change(br, 0); |
1da177e4 | 81 | br->topology_change_detected = 0; |
78872ccb | 82 | spin_unlock_bh(&br->lock); |
1da177e4 LT |
83 | |
84 | del_timer_sync(&br->hello_timer); | |
85 | del_timer_sync(&br->topology_change_timer); | |
86 | del_timer_sync(&br->tcn_timer); | |
f7cdee8a | 87 | cancel_delayed_work_sync(&br->gc_work); |
1da177e4 LT |
88 | } |
89 | ||
90 | /* called under bridge lock */ | |
91 | void br_stp_enable_port(struct net_bridge_port *p) | |
92 | { | |
93 | br_init_port(p); | |
94 | br_port_state_selection(p->br); | |
92899063 | 95 | br_ifinfo_notify(RTM_NEWLINK, NULL, p); |
1da177e4 LT |
96 | } |
97 | ||
98 | /* called under bridge lock */ | |
99 | void br_stp_disable_port(struct net_bridge_port *p) | |
100 | { | |
28a16c97 | 101 | struct net_bridge *br = p->br; |
1da177e4 LT |
102 | int wasroot; |
103 | ||
1da177e4 LT |
104 | wasroot = br_is_root_bridge(br); |
105 | br_become_designated_port(p); | |
775dd692 | 106 | br_set_state(p, BR_STATE_DISABLED); |
1da177e4 LT |
107 | p->topology_change_ack = 0; |
108 | p->config_pending = 0; | |
109 | ||
92899063 | 110 | br_ifinfo_notify(RTM_NEWLINK, NULL, p); |
4ecb961c | 111 | |
1da177e4 LT |
112 | del_timer(&p->message_age_timer); |
113 | del_timer(&p->forward_delay_timer); | |
114 | del_timer(&p->hold_timer); | |
115 | ||
8dc35020 NA |
116 | if (!rcu_access_pointer(p->backup_port)) |
117 | br_fdb_delete_by_port(br, p, 0, 0); | |
3fe2d7c7 | 118 | br_multicast_disable_port(p); |
1a620698 | 119 | |
1da177e4 LT |
120 | br_configuration_update(br); |
121 | ||
122 | br_port_state_selection(br); | |
123 | ||
124 | if (br_is_root_bridge(br) && !wasroot) | |
125 | br_become_root_bridge(br); | |
126 | } | |
127 | ||
30843315 | 128 | static int br_stp_call_user(struct net_bridge *br, char *arg) |
9cde0708 | 129 | { |
30843315 | 130 | char *argv[] = { BR_STP_PROG, br->dev->name, arg, NULL }; |
9cde0708 | 131 | char *envp[] = { NULL }; |
30843315 VD |
132 | int rc; |
133 | ||
134 | /* call userspace STP and report program errors */ | |
135 | rc = call_usermodehelper(BR_STP_PROG, argv, envp, UMH_WAIT_PROC); | |
136 | if (rc > 0) { | |
137 | if (rc & 0xff) | |
138 | br_debug(br, BR_STP_PROG " received signal %d\n", | |
139 | rc & 0x7f); | |
140 | else | |
141 | br_debug(br, BR_STP_PROG " exited with code %d\n", | |
142 | (rc >> 8) & 0xff); | |
143 | } | |
144 | ||
145 | return rc; | |
146 | } | |
147 | ||
148 | static void br_stp_start(struct net_bridge *br) | |
149 | { | |
30843315 | 150 | int err = -ENOENT; |
9cde0708 | 151 | |
ff621985 | 152 | if (net_eq(dev_net(br->dev), &init_net)) |
30843315 VD |
153 | err = br_stp_call_user(br, "start"); |
154 | ||
155 | if (err && err != -ENOENT) | |
156 | br_err(br, "failed to start userspace STP (%d)\n", err); | |
be4f154d HX |
157 | |
158 | spin_lock_bh(&br->lock); | |
159 | ||
160 | if (br->bridge_forward_delay < BR_MIN_FORWARD_DELAY) | |
161 | __br_set_forward_delay(br, BR_MIN_FORWARD_DELAY); | |
4b6c7879 | 162 | else if (br->bridge_forward_delay > BR_MAX_FORWARD_DELAY) |
be4f154d HX |
163 | __br_set_forward_delay(br, BR_MAX_FORWARD_DELAY); |
164 | ||
30843315 | 165 | if (!err) { |
9cde0708 | 166 | br->stp_enabled = BR_USER_STP; |
28a16c97 | 167 | br_debug(br, "userspace STP started\n"); |
9cde0708 SH |
168 | } else { |
169 | br->stp_enabled = BR_KERNEL_STP; | |
28a16c97 | 170 | br_debug(br, "using kernel STP\n"); |
9cde0708 SH |
171 | |
172 | /* To start timers on any ports left in blocking */ | |
aeb07324 NA |
173 | if (br->dev->flags & IFF_UP) |
174 | mod_timer(&br->hello_timer, jiffies + br->hello_time); | |
9cde0708 | 175 | br_port_state_selection(br); |
9cde0708 | 176 | } |
be4f154d HX |
177 | |
178 | spin_unlock_bh(&br->lock); | |
9cde0708 SH |
179 | } |
180 | ||
181 | static void br_stp_stop(struct net_bridge *br) | |
182 | { | |
30843315 | 183 | int err; |
9cde0708 SH |
184 | |
185 | if (br->stp_enabled == BR_USER_STP) { | |
30843315 VD |
186 | err = br_stp_call_user(br, "stop"); |
187 | if (err) | |
188 | br_err(br, "failed to stop userspace STP (%d)\n", err); | |
9cde0708 SH |
189 | |
190 | /* To start timers on any ports left in blocking */ | |
191 | spin_lock_bh(&br->lock); | |
192 | br_port_state_selection(br); | |
193 | spin_unlock_bh(&br->lock); | |
194 | } | |
195 | ||
196 | br->stp_enabled = BR_NO_STP; | |
197 | } | |
198 | ||
199 | void br_stp_set_enabled(struct net_bridge *br, unsigned long val) | |
200 | { | |
201 | ASSERT_RTNL(); | |
202 | ||
203 | if (val) { | |
204 | if (br->stp_enabled == BR_NO_STP) | |
205 | br_stp_start(br); | |
206 | } else { | |
207 | if (br->stp_enabled != BR_NO_STP) | |
208 | br_stp_stop(br); | |
209 | } | |
210 | } | |
211 | ||
1da177e4 | 212 | /* called under bridge lock */ |
4505a3ef | 213 | void br_stp_change_bridge_id(struct net_bridge *br, const unsigned char *addr) |
1da177e4 | 214 | { |
9a7b6ef9 | 215 | /* should be aligned on 2 bytes for ether_addr_equal() */ |
19bb3506 EK |
216 | unsigned short oldaddr_aligned[ETH_ALEN >> 1]; |
217 | unsigned char *oldaddr = (unsigned char *)oldaddr_aligned; | |
1da177e4 LT |
218 | struct net_bridge_port *p; |
219 | int wasroot; | |
220 | ||
221 | wasroot = br_is_root_bridge(br); | |
222 | ||
a4b816d8 TM |
223 | br_fdb_change_mac_address(br, addr); |
224 | ||
1da177e4 LT |
225 | memcpy(oldaddr, br->bridge_id.addr, ETH_ALEN); |
226 | memcpy(br->bridge_id.addr, addr, ETH_ALEN); | |
227 | memcpy(br->dev->dev_addr, addr, ETH_ALEN); | |
228 | ||
229 | list_for_each_entry(p, &br->port_list, list) { | |
9a7b6ef9 | 230 | if (ether_addr_equal(p->designated_bridge.addr, oldaddr)) |
1da177e4 LT |
231 | memcpy(p->designated_bridge.addr, addr, ETH_ALEN); |
232 | ||
9a7b6ef9 | 233 | if (ether_addr_equal(p->designated_root.addr, oldaddr)) |
1da177e4 | 234 | memcpy(p->designated_root.addr, addr, ETH_ALEN); |
1da177e4 LT |
235 | } |
236 | ||
237 | br_configuration_update(br); | |
238 | br_port_state_selection(br); | |
239 | if (br_is_root_bridge(br) && !wasroot) | |
240 | br_become_root_bridge(br); | |
241 | } | |
242 | ||
9a7b6ef9 | 243 | /* should be aligned on 2 bytes for ether_addr_equal() */ |
19bb3506 | 244 | static const unsigned short br_mac_zero_aligned[ETH_ALEN >> 1]; |
1da177e4 LT |
245 | |
246 | /* called under bridge lock */ | |
edf947f1 | 247 | bool br_stp_recalculate_bridge_id(struct net_bridge *br) |
1da177e4 | 248 | { |
19bb3506 EK |
249 | const unsigned char *br_mac_zero = |
250 | (const unsigned char *)br_mac_zero_aligned; | |
1da177e4 LT |
251 | const unsigned char *addr = br_mac_zero; |
252 | struct net_bridge_port *p; | |
253 | ||
92c0574f | 254 | /* user has chosen a value so keep it */ |
b2748267 | 255 | if (br->dev->addr_assign_type == NET_ADDR_SET) |
1459a3cc | 256 | return false; |
92c0574f | 257 | |
1da177e4 LT |
258 | list_for_each_entry(p, &br->port_list, list) { |
259 | if (addr == br_mac_zero || | |
554c9a8e | 260 | memcmp(p->dev->dev_addr, addr, ETH_ALEN) < 0) |
1da177e4 LT |
261 | addr = p->dev->dev_addr; |
262 | ||
263 | } | |
264 | ||
9a7b6ef9 | 265 | if (ether_addr_equal(br->bridge_id.addr, addr)) |
edf947f1 | 266 | return false; /* no change */ |
267 | ||
268 | br_stp_change_bridge_id(br, addr); | |
269 | return true; | |
1da177e4 LT |
270 | } |
271 | ||
2dab80a8 | 272 | /* Acquires and releases bridge lock */ |
1da177e4 LT |
273 | void br_stp_set_bridge_priority(struct net_bridge *br, u16 newprio) |
274 | { | |
275 | struct net_bridge_port *p; | |
276 | int wasroot; | |
277 | ||
2dab80a8 | 278 | spin_lock_bh(&br->lock); |
1da177e4 LT |
279 | wasroot = br_is_root_bridge(br); |
280 | ||
281 | list_for_each_entry(p, &br->port_list, list) { | |
282 | if (p->state != BR_STATE_DISABLED && | |
283 | br_is_designated_port(p)) { | |
284 | p->designated_bridge.prio[0] = (newprio >> 8) & 0xFF; | |
285 | p->designated_bridge.prio[1] = newprio & 0xFF; | |
286 | } | |
287 | ||
288 | } | |
289 | ||
290 | br->bridge_id.prio[0] = (newprio >> 8) & 0xFF; | |
291 | br->bridge_id.prio[1] = newprio & 0xFF; | |
292 | br_configuration_update(br); | |
293 | br_port_state_selection(br); | |
294 | if (br_is_root_bridge(br) && !wasroot) | |
295 | br_become_root_bridge(br); | |
2dab80a8 | 296 | spin_unlock_bh(&br->lock); |
1da177e4 LT |
297 | } |
298 | ||
299 | /* called under bridge lock */ | |
14f98f25 | 300 | int br_stp_set_port_priority(struct net_bridge_port *p, unsigned long newprio) |
1da177e4 | 301 | { |
14f98f25 | 302 | port_id new_port_id; |
303 | ||
304 | if (newprio > BR_MAX_PORT_PRIORITY) | |
305 | return -ERANGE; | |
1da177e4 | 306 | |
14f98f25 | 307 | new_port_id = br_make_port_id(newprio, p->port_no); |
1da177e4 LT |
308 | if (br_is_designated_port(p)) |
309 | p->designated_port = new_port_id; | |
310 | ||
311 | p->port_id = new_port_id; | |
312 | p->priority = newprio; | |
313 | if (!memcmp(&p->br->bridge_id, &p->designated_bridge, 8) && | |
314 | p->port_id < p->designated_port) { | |
315 | br_become_designated_port(p); | |
316 | br_port_state_selection(p->br); | |
317 | } | |
14f98f25 | 318 | |
319 | return 0; | |
1da177e4 LT |
320 | } |
321 | ||
322 | /* called under bridge lock */ | |
14f98f25 | 323 | int br_stp_set_path_cost(struct net_bridge_port *p, unsigned long path_cost) |
1da177e4 | 324 | { |
14f98f25 | 325 | if (path_cost < BR_MIN_PATH_COST || |
326 | path_cost > BR_MAX_PATH_COST) | |
327 | return -ERANGE; | |
328 | ||
8f3359bd | 329 | p->flags |= BR_ADMIN_COST; |
1da177e4 LT |
330 | p->path_cost = path_cost; |
331 | br_configuration_update(p->br); | |
332 | br_port_state_selection(p->br); | |
14f98f25 | 333 | return 0; |
1da177e4 LT |
334 | } |
335 | ||
336 | ssize_t br_show_bridge_id(char *buf, const struct bridge_id *id) | |
337 | { | |
338 | return sprintf(buf, "%.2x%.2x.%.2x%.2x%.2x%.2x%.2x%.2x\n", | |
339 | id->prio[0], id->prio[1], | |
340 | id->addr[0], id->addr[1], id->addr[2], | |
341 | id->addr[3], id->addr[4], id->addr[5]); | |
342 | } |