1 /*
2  *	Linux ethernet bridge
3  *
4  *	Authors:
5  *	Lennert Buytenhek		<buytenh@gnu.org>
6  *
7  *	This program is free software; you can redistribute it and/or
8  *	modify it under the terms of the GNU General Public License
9  *	as published by the Free Software Foundation; either version
10  *	2 of the License, or (at your option) any later version.
11  */
12 
13 #ifndef _BR_PRIVATE_H
14 #define _BR_PRIVATE_H
15 
16 #include <linux/netdevice.h>
17 #include <linux/if_bridge.h>
18 #include <linux/netpoll.h>
19 #include <linux/u64_stats_sync.h>
20 #include <net/route.h>
21 
22 #define BR_HASH_BITS 8
23 #define BR_HASH_SIZE (1 << BR_HASH_BITS)
24 
25 #define BR_HOLD_TIME (1*HZ)
26 
27 #define BR_PORT_BITS	10
28 #define BR_MAX_PORTS	(1<<BR_PORT_BITS)
29 
30 #define BR_VERSION	"2.3"
31 
32 /* Control of forwarding link local multicast */
33 #define BR_GROUPFWD_DEFAULT	0
34 /* Don't allow forwarding control protocols like STP and LLDP */
35 #define BR_GROUPFWD_RESTRICTED	0x4007u
36 
37 /* Path to usermode spanning tree program */
38 #define BR_STP_PROG	"/sbin/bridge-stp"
39 
40 typedef struct bridge_id bridge_id;
41 typedef struct mac_addr mac_addr;
42 typedef __u16 port_id;
43 
44 struct bridge_id
45 {
46 	unsigned char	prio[2];
47 	unsigned char	addr[6];
48 };
49 
50 struct mac_addr
51 {
52 	unsigned char	addr[6];
53 };
54 
55 struct br_ip
56 {
57 	union {
58 		__be32	ip4;
59 #if IS_ENABLED(CONFIG_IPV6)
60 		struct in6_addr ip6;
61 #endif
62 	} u;
63 	__be16		proto;
64 };
65 
66 struct net_bridge_fdb_entry
67 {
68 	struct hlist_node		hlist;
69 	struct net_bridge_port		*dst;
70 
71 	struct rcu_head			rcu;
72 	unsigned long			updated;
73 	unsigned long			used;
74 	mac_addr			addr;
75 	unsigned char			is_local;
76 	unsigned char			is_static;
77 };
78 
79 struct net_bridge_port_group {
80 	struct net_bridge_port		*port;
81 	struct net_bridge_port_group __rcu *next;
82 	struct hlist_node		mglist;
83 	struct rcu_head			rcu;
84 	struct timer_list		timer;
85 	struct br_ip			addr;
86 };
87 
88 struct net_bridge_mdb_entry
89 {
90 	struct hlist_node		hlist[2];
91 	struct net_bridge		*br;
92 	struct net_bridge_port_group __rcu *ports;
93 	struct rcu_head			rcu;
94 	struct timer_list		timer;
95 	struct br_ip			addr;
96 	bool				mglist;
97 };
98 
99 struct net_bridge_mdb_htable
100 {
101 	struct hlist_head		*mhash;
102 	struct rcu_head			rcu;
103 	struct net_bridge_mdb_htable	*old;
104 	u32				size;
105 	u32				max;
106 	u32				secret;
107 	u32				ver;
108 };
109 
110 struct net_bridge_port
111 {
112 	struct net_bridge		*br;
113 	struct net_device		*dev;
114 	struct list_head		list;
115 
116 	/* STP */
117 	u8				priority;
118 	u8				state;
119 	u16				port_no;
120 	unsigned char			topology_change_ack;
121 	unsigned char			config_pending;
122 	port_id				port_id;
123 	port_id				designated_port;
124 	bridge_id			designated_root;
125 	bridge_id			designated_bridge;
126 	u32				path_cost;
127 	u32				designated_cost;
128 	unsigned long			designated_age;
129 
130 	struct timer_list		forward_delay_timer;
131 	struct timer_list		hold_timer;
132 	struct timer_list		message_age_timer;
133 	struct kobject			kobj;
134 	struct rcu_head			rcu;
135 
136 	unsigned long 			flags;
137 #define BR_HAIRPIN_MODE		0x00000001
138 
139 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
140 	u32				multicast_startup_queries_sent;
141 	unsigned char			multicast_router;
142 	struct timer_list		multicast_router_timer;
143 	struct timer_list		multicast_query_timer;
144 	struct hlist_head		mglist;
145 	struct hlist_node		rlist;
146 #endif
147 
148 #ifdef CONFIG_SYSFS
149 	char				sysfs_name[IFNAMSIZ];
150 #endif
151 
152 #ifdef CONFIG_NET_POLL_CONTROLLER
153 	struct netpoll			*np;
154 #endif
155 };
156 
157 #define br_port_exists(dev) (dev->priv_flags & IFF_BRIDGE_PORT)
158 
br_port_get_rcu(const struct net_device * dev)159 static inline struct net_bridge_port *br_port_get_rcu(const struct net_device *dev)
160 {
161 	struct net_bridge_port *port = rcu_dereference(dev->rx_handler_data);
162 	return br_port_exists(dev) ? port : NULL;
163 }
164 
br_port_get_rtnl(struct net_device * dev)165 static inline struct net_bridge_port *br_port_get_rtnl(struct net_device *dev)
166 {
167 	return br_port_exists(dev) ?
168 		rtnl_dereference(dev->rx_handler_data) : NULL;
169 }
170 
171 struct br_cpu_netstats {
172 	u64			rx_packets;
173 	u64			rx_bytes;
174 	u64			tx_packets;
175 	u64			tx_bytes;
176 	struct u64_stats_sync	syncp;
177 };
178 
179 struct net_bridge
180 {
181 	spinlock_t			lock;
182 	struct list_head		port_list;
183 	struct net_device		*dev;
184 
185 	struct br_cpu_netstats __percpu *stats;
186 	spinlock_t			hash_lock;
187 	struct hlist_head		hash[BR_HASH_SIZE];
188 #ifdef CONFIG_BRIDGE_NETFILTER
189 	struct rtable 			fake_rtable;
190 	bool				nf_call_iptables;
191 	bool				nf_call_ip6tables;
192 	bool				nf_call_arptables;
193 #endif
194 	unsigned long			flags;
195 #define BR_SET_MAC_ADDR		0x00000001
196 
197 	u16				group_fwd_mask;
198 
199 	/* STP */
200 	bridge_id			designated_root;
201 	bridge_id			bridge_id;
202 	u32				root_path_cost;
203 	unsigned long			max_age;
204 	unsigned long			hello_time;
205 	unsigned long			forward_delay;
206 	unsigned long			bridge_max_age;
207 	unsigned long			ageing_time;
208 	unsigned long			bridge_hello_time;
209 	unsigned long			bridge_forward_delay;
210 
211 	u8				group_addr[ETH_ALEN];
212 	u16				root_port;
213 
214 	enum {
215 		BR_NO_STP, 		/* no spanning tree */
216 		BR_KERNEL_STP,		/* old STP in kernel */
217 		BR_USER_STP,		/* new RSTP in userspace */
218 	} stp_enabled;
219 
220 	unsigned char			topology_change;
221 	unsigned char			topology_change_detected;
222 
223 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
224 	unsigned char			multicast_router;
225 
226 	u8				multicast_disabled:1;
227 
228 	u32				hash_elasticity;
229 	u32				hash_max;
230 
231 	u32				multicast_last_member_count;
232 	u32				multicast_startup_queries_sent;
233 	u32				multicast_startup_query_count;
234 
235 	unsigned long			multicast_last_member_interval;
236 	unsigned long			multicast_membership_interval;
237 	unsigned long			multicast_querier_interval;
238 	unsigned long			multicast_query_interval;
239 	unsigned long			multicast_query_response_interval;
240 	unsigned long			multicast_startup_query_interval;
241 
242 	spinlock_t			multicast_lock;
243 	struct net_bridge_mdb_htable __rcu *mdb;
244 	struct hlist_head		router_list;
245 
246 	struct timer_list		multicast_router_timer;
247 	struct timer_list		multicast_querier_timer;
248 	struct timer_list		multicast_query_timer;
249 #endif
250 
251 	struct timer_list		hello_timer;
252 	struct timer_list		tcn_timer;
253 	struct timer_list		topology_change_timer;
254 	struct timer_list		gc_timer;
255 	struct kobject			*ifobj;
256 };
257 
258 struct br_input_skb_cb {
259 	struct net_device *brdev;
260 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
261 	int igmp;
262 	int mrouters_only;
263 #endif
264 };
265 
266 #define BR_INPUT_SKB_CB(__skb)	((struct br_input_skb_cb *)(__skb)->cb)
267 
268 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
269 # define BR_INPUT_SKB_CB_MROUTERS_ONLY(__skb)	(BR_INPUT_SKB_CB(__skb)->mrouters_only)
270 #else
271 # define BR_INPUT_SKB_CB_MROUTERS_ONLY(__skb)	(0)
272 #endif
273 
274 #define br_printk(level, br, format, args...)	\
275 	printk(level "%s: " format, (br)->dev->name, ##args)
276 
277 #define br_err(__br, format, args...)			\
278 	br_printk(KERN_ERR, __br, format, ##args)
279 #define br_warn(__br, format, args...)			\
280 	br_printk(KERN_WARNING, __br, format, ##args)
281 #define br_notice(__br, format, args...)		\
282 	br_printk(KERN_NOTICE, __br, format, ##args)
283 #define br_info(__br, format, args...)			\
284 	br_printk(KERN_INFO, __br, format, ##args)
285 
286 #define br_debug(br, format, args...)			\
287 	pr_debug("%s: " format,  (br)->dev->name, ##args)
288 
289 extern struct notifier_block br_device_notifier;
290 extern const u8 br_group_address[ETH_ALEN];
291 
292 /* called under bridge lock */
br_is_root_bridge(const struct net_bridge * br)293 static inline int br_is_root_bridge(const struct net_bridge *br)
294 {
295 	return !memcmp(&br->bridge_id, &br->designated_root, 8);
296 }
297 
298 /* br_device.c */
299 extern void br_dev_setup(struct net_device *dev);
300 extern void br_dev_delete(struct net_device *dev, struct list_head *list);
301 extern netdev_tx_t br_dev_xmit(struct sk_buff *skb,
302 			       struct net_device *dev);
303 #ifdef CONFIG_NET_POLL_CONTROLLER
br_netpoll_info(struct net_bridge * br)304 static inline struct netpoll_info *br_netpoll_info(struct net_bridge *br)
305 {
306 	return br->dev->npinfo;
307 }
308 
br_netpoll_send_skb(const struct net_bridge_port * p,struct sk_buff * skb)309 static inline void br_netpoll_send_skb(const struct net_bridge_port *p,
310 				       struct sk_buff *skb)
311 {
312 	struct netpoll *np = p->np;
313 
314 	if (np)
315 		netpoll_send_skb(np, skb);
316 }
317 
318 extern int br_netpoll_enable(struct net_bridge_port *p);
319 extern void br_netpoll_disable(struct net_bridge_port *p);
320 #else
br_netpoll_info(struct net_bridge * br)321 static inline struct netpoll_info *br_netpoll_info(struct net_bridge *br)
322 {
323 	return NULL;
324 }
325 
br_netpoll_send_skb(const struct net_bridge_port * p,struct sk_buff * skb)326 static inline void br_netpoll_send_skb(const struct net_bridge_port *p,
327 				       struct sk_buff *skb)
328 {
329 }
330 
br_netpoll_enable(struct net_bridge_port * p)331 static inline int br_netpoll_enable(struct net_bridge_port *p)
332 {
333 	return 0;
334 }
335 
br_netpoll_disable(struct net_bridge_port * p)336 static inline void br_netpoll_disable(struct net_bridge_port *p)
337 {
338 }
339 #endif
340 
341 /* br_fdb.c */
342 extern int br_fdb_init(void);
343 extern void br_fdb_fini(void);
344 extern void br_fdb_flush(struct net_bridge *br);
345 extern void br_fdb_changeaddr(struct net_bridge_port *p,
346 			      const unsigned char *newaddr);
347 extern void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr);
348 extern void br_fdb_cleanup(unsigned long arg);
349 extern void br_fdb_delete_by_port(struct net_bridge *br,
350 				  const struct net_bridge_port *p, int do_all);
351 extern struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br,
352 						 const unsigned char *addr);
353 extern int br_fdb_test_addr(struct net_device *dev, unsigned char *addr);
354 extern int br_fdb_fillbuf(struct net_bridge *br, void *buf,
355 			  unsigned long count, unsigned long off);
356 extern int br_fdb_insert(struct net_bridge *br,
357 			 struct net_bridge_port *source,
358 			 const unsigned char *addr);
359 extern void br_fdb_update(struct net_bridge *br,
360 			  struct net_bridge_port *source,
361 			  const unsigned char *addr);
362 extern int br_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb);
363 extern int br_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg);
364 extern int br_fdb_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg);
365 
366 /* br_forward.c */
367 extern void br_deliver(const struct net_bridge_port *to,
368 		struct sk_buff *skb);
369 extern int br_dev_queue_push_xmit(struct sk_buff *skb);
370 extern void br_forward(const struct net_bridge_port *to,
371 		struct sk_buff *skb, struct sk_buff *skb0);
372 extern int br_forward_finish(struct sk_buff *skb);
373 extern void br_flood_deliver(struct net_bridge *br, struct sk_buff *skb);
374 extern void br_flood_forward(struct net_bridge *br, struct sk_buff *skb,
375 			     struct sk_buff *skb2);
376 
377 /* br_if.c */
378 extern void br_port_carrier_check(struct net_bridge_port *p);
379 extern int br_add_bridge(struct net *net, const char *name);
380 extern int br_del_bridge(struct net *net, const char *name);
381 extern void br_net_exit(struct net *net);
382 extern int br_add_if(struct net_bridge *br,
383 	      struct net_device *dev);
384 extern int br_del_if(struct net_bridge *br,
385 	      struct net_device *dev);
386 extern int br_min_mtu(const struct net_bridge *br);
387 extern netdev_features_t br_features_recompute(struct net_bridge *br,
388 	netdev_features_t features);
389 
390 /* br_input.c */
391 extern int br_handle_frame_finish(struct sk_buff *skb);
392 extern rx_handler_result_t br_handle_frame(struct sk_buff **pskb);
393 
394 /* br_ioctl.c */
395 extern int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);
396 extern int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd, void __user *arg);
397 
398 /* br_multicast.c */
399 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
400 extern int br_multicast_rcv(struct net_bridge *br,
401 			    struct net_bridge_port *port,
402 			    struct sk_buff *skb);
403 extern struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
404 					       struct sk_buff *skb);
405 extern void br_multicast_add_port(struct net_bridge_port *port);
406 extern void br_multicast_del_port(struct net_bridge_port *port);
407 extern void br_multicast_enable_port(struct net_bridge_port *port);
408 extern void br_multicast_disable_port(struct net_bridge_port *port);
409 extern void br_multicast_init(struct net_bridge *br);
410 extern void br_multicast_open(struct net_bridge *br);
411 extern void br_multicast_stop(struct net_bridge *br);
412 extern void br_multicast_deliver(struct net_bridge_mdb_entry *mdst,
413 				 struct sk_buff *skb);
414 extern void br_multicast_forward(struct net_bridge_mdb_entry *mdst,
415 				 struct sk_buff *skb, struct sk_buff *skb2);
416 extern int br_multicast_set_router(struct net_bridge *br, unsigned long val);
417 extern int br_multicast_set_port_router(struct net_bridge_port *p,
418 					unsigned long val);
419 extern int br_multicast_toggle(struct net_bridge *br, unsigned long val);
420 extern int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val);
421 
br_multicast_is_router(struct net_bridge * br)422 static inline bool br_multicast_is_router(struct net_bridge *br)
423 {
424 	return br->multicast_router == 2 ||
425 	       (br->multicast_router == 1 &&
426 		timer_pending(&br->multicast_router_timer));
427 }
428 #else
br_multicast_rcv(struct net_bridge * br,struct net_bridge_port * port,struct sk_buff * skb)429 static inline int br_multicast_rcv(struct net_bridge *br,
430 				   struct net_bridge_port *port,
431 				   struct sk_buff *skb)
432 {
433 	return 0;
434 }
435 
br_mdb_get(struct net_bridge * br,struct sk_buff * skb)436 static inline struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
437 						      struct sk_buff *skb)
438 {
439 	return NULL;
440 }
441 
br_multicast_add_port(struct net_bridge_port * port)442 static inline void br_multicast_add_port(struct net_bridge_port *port)
443 {
444 }
445 
br_multicast_del_port(struct net_bridge_port * port)446 static inline void br_multicast_del_port(struct net_bridge_port *port)
447 {
448 }
449 
br_multicast_enable_port(struct net_bridge_port * port)450 static inline void br_multicast_enable_port(struct net_bridge_port *port)
451 {
452 }
453 
br_multicast_disable_port(struct net_bridge_port * port)454 static inline void br_multicast_disable_port(struct net_bridge_port *port)
455 {
456 }
457 
br_multicast_init(struct net_bridge * br)458 static inline void br_multicast_init(struct net_bridge *br)
459 {
460 }
461 
br_multicast_open(struct net_bridge * br)462 static inline void br_multicast_open(struct net_bridge *br)
463 {
464 }
465 
br_multicast_stop(struct net_bridge * br)466 static inline void br_multicast_stop(struct net_bridge *br)
467 {
468 }
469 
br_multicast_deliver(struct net_bridge_mdb_entry * mdst,struct sk_buff * skb)470 static inline void br_multicast_deliver(struct net_bridge_mdb_entry *mdst,
471 					struct sk_buff *skb)
472 {
473 }
474 
br_multicast_forward(struct net_bridge_mdb_entry * mdst,struct sk_buff * skb,struct sk_buff * skb2)475 static inline void br_multicast_forward(struct net_bridge_mdb_entry *mdst,
476 					struct sk_buff *skb,
477 					struct sk_buff *skb2)
478 {
479 }
br_multicast_is_router(struct net_bridge * br)480 static inline bool br_multicast_is_router(struct net_bridge *br)
481 {
482 	return 0;
483 }
484 #endif
485 
486 /* br_netfilter.c */
487 #ifdef CONFIG_BRIDGE_NETFILTER
488 extern int br_netfilter_init(void);
489 extern void br_netfilter_fini(void);
490 extern void br_netfilter_rtable_init(struct net_bridge *);
491 #else
492 #define br_netfilter_init()	(0)
493 #define br_netfilter_fini()	do { } while(0)
494 #define br_netfilter_rtable_init(x)
495 #endif
496 
497 /* br_stp.c */
498 extern void br_log_state(const struct net_bridge_port *p);
499 extern struct net_bridge_port *br_get_port(struct net_bridge *br,
500 					   u16 port_no);
501 extern void br_init_port(struct net_bridge_port *p);
502 extern void br_become_designated_port(struct net_bridge_port *p);
503 
504 extern void __br_set_forward_delay(struct net_bridge *br, unsigned long t);
505 extern int br_set_forward_delay(struct net_bridge *br, unsigned long x);
506 extern int br_set_hello_time(struct net_bridge *br, unsigned long x);
507 extern int br_set_max_age(struct net_bridge *br, unsigned long x);
508 
509 
510 /* br_stp_if.c */
511 extern void br_stp_enable_bridge(struct net_bridge *br);
512 extern void br_stp_disable_bridge(struct net_bridge *br);
513 extern void br_stp_set_enabled(struct net_bridge *br, unsigned long val);
514 extern void br_stp_enable_port(struct net_bridge_port *p);
515 extern void br_stp_disable_port(struct net_bridge_port *p);
516 extern bool br_stp_recalculate_bridge_id(struct net_bridge *br);
517 extern void br_stp_change_bridge_id(struct net_bridge *br, const unsigned char *a);
518 extern void br_stp_set_bridge_priority(struct net_bridge *br,
519 				       u16 newprio);
520 extern int br_stp_set_port_priority(struct net_bridge_port *p,
521 				    unsigned long newprio);
522 extern int br_stp_set_path_cost(struct net_bridge_port *p,
523 				unsigned long path_cost);
524 extern ssize_t br_show_bridge_id(char *buf, const struct bridge_id *id);
525 
526 /* br_stp_bpdu.c */
527 struct stp_proto;
528 extern void br_stp_rcv(const struct stp_proto *proto, struct sk_buff *skb,
529 		       struct net_device *dev);
530 
531 /* br_stp_timer.c */
532 extern void br_stp_timer_init(struct net_bridge *br);
533 extern void br_stp_port_timer_init(struct net_bridge_port *p);
534 extern unsigned long br_timer_value(const struct timer_list *timer);
535 
536 /* br.c */
537 #if IS_ENABLED(CONFIG_ATM_LANE)
538 extern int (*br_fdb_test_addr_hook)(struct net_device *dev, unsigned char *addr);
539 #endif
540 
541 /* br_netlink.c */
542 extern struct rtnl_link_ops br_link_ops;
543 extern int br_netlink_init(void);
544 extern void br_netlink_fini(void);
545 extern void br_ifinfo_notify(int event, struct net_bridge_port *port);
546 
547 #ifdef CONFIG_SYSFS
548 /* br_sysfs_if.c */
549 extern const struct sysfs_ops brport_sysfs_ops;
550 extern int br_sysfs_addif(struct net_bridge_port *p);
551 extern int br_sysfs_renameif(struct net_bridge_port *p);
552 
553 /* br_sysfs_br.c */
554 extern int br_sysfs_addbr(struct net_device *dev);
555 extern void br_sysfs_delbr(struct net_device *dev);
556 
557 #else
558 
559 #define br_sysfs_addif(p)	(0)
560 #define br_sysfs_renameif(p)	(0)
561 #define br_sysfs_addbr(dev)	(0)
562 #define br_sysfs_delbr(dev)	do { } while(0)
563 #endif /* CONFIG_SYSFS */
564 
565 #endif
566