1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *	Linux ethernet bridge
4  *
5  *	Authors:
6  *	Lennert Buytenhek		<buytenh@gnu.org>
7  */
8 
9 #ifndef _BR_PRIVATE_STP_H
10 #define _BR_PRIVATE_STP_H
11 
12 #define BPDU_TYPE_CONFIG 0
13 #define BPDU_TYPE_TCN 0x80
14 
15 /* IEEE 802.1D-1998 timer values */
16 #define BR_MIN_HELLO_TIME	(1*HZ)
17 #define BR_MAX_HELLO_TIME	(10*HZ)
18 
19 #define BR_MIN_FORWARD_DELAY	(2*HZ)
20 #define BR_MAX_FORWARD_DELAY	(30*HZ)
21 
22 #define BR_MIN_MAX_AGE		(6*HZ)
23 #define BR_MAX_MAX_AGE		(40*HZ)
24 
25 #define BR_MIN_PATH_COST	1
26 #define BR_MAX_PATH_COST	65535
27 
28 struct br_config_bpdu {
29 	unsigned int	topology_change:1;
30 	unsigned int	topology_change_ack:1;
31 	bridge_id	root;
32 	int		root_path_cost;
33 	bridge_id	bridge_id;
34 	port_id		port_id;
35 	int		message_age;
36 	int		max_age;
37 	int		hello_time;
38 	int		forward_delay;
39 };
40 
41 /* called under bridge lock */
br_is_designated_port(const struct net_bridge_port * p)42 static inline int br_is_designated_port(const struct net_bridge_port *p)
43 {
44 	return !memcmp(&p->designated_bridge, &p->br->bridge_id, 8) &&
45 		(p->designated_port == p->port_id);
46 }
47 
48 
49 /* br_stp.c */
50 void br_become_root_bridge(struct net_bridge *br);
51 void br_config_bpdu_generation(struct net_bridge *);
52 void br_configuration_update(struct net_bridge *);
53 void br_port_state_selection(struct net_bridge *);
54 void br_received_config_bpdu(struct net_bridge_port *p,
55 			     const struct br_config_bpdu *bpdu);
56 void br_received_tcn_bpdu(struct net_bridge_port *p);
57 void br_transmit_config(struct net_bridge_port *p);
58 void br_transmit_tcn(struct net_bridge *br);
59 void br_topology_change_detection(struct net_bridge *br);
60 void __br_set_topology_change(struct net_bridge *br, unsigned char val);
61 
62 /* br_stp_bpdu.c */
63 void br_send_config_bpdu(struct net_bridge_port *, struct br_config_bpdu *);
64 void br_send_tcn_bpdu(struct net_bridge_port *);
65 
66 #endif
67