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/*
* Constants and structure definitions for the bridging code
*/
#if !defined(One)
#define Zero 0
#define One 1
#endif /* !defined(One) */
#if !defined(TRUE)
#define FALSE 0
#define TRUE 1
#endif /* !defined(TRUE) */
/** port states. **/
#define Disabled 0 /* (4.4 5) */
#define Listening 1 /* (4.4.2) */
#define Learning 2 /* (4.4.3) */
#define Forwarding 3 /* (4 4 4) */
#define Blocking 4 /* (4.4.1) */
#define No_of_ports 8
/* arbitrary choice, to allow the code below to compile */
#define All_ports (No_of_ports + 1)
/*
* We time out our entries in the FDB after this many seconds.
*/
#define FDB_TIMEOUT 300
/*
* the following defines are the initial values used when the
* bridge is booted. These may be overridden when this bridge is
* not the root bridge. These are the recommended default values
* from the 802.1d specification.
*/
#define BRIDGE_MAX_AGE 20
#define BRIDGE_HELLO_TIME 2
#define BRIDGE_FORWARD_DELAY 15
#define HOLD_TIME 1
#define Default_path_cost 10
/*
* minimum increment possible to avoid underestimating age, allows for BPDU
* transmission time
*/
#define Message_age_increment 1
#define No_port 0
/*
* reserved value for Bridge's root port parameter indicating no root port,
* used when Bridge is the root - also used to indicate the source when
* a frame is being generated by a higher layer protocol on this host
*/
/** Configuration BPDU Parameters (4.5.1) **/
typedef struct {
union {
struct {
unsigned short priority;
unsigned char ula[6];
} p_u;
unsigned int id[2];
} bi;
} bridge_id_t;
#define BRIDGE_PRIORITY bi.p_u.priority
#define BRIDGE_ID_ULA bi.p_u.ula
#define BRIDGE_ID bi.id
typedef struct {
unsigned short protocol_id;
unsigned char protocol_version_id;
unsigned char type;
unsigned char flags;
#define TOPOLOGY_CHANGE 0x01
#define TOPOLOGY_CHANGE_ACK 0x80
bridge_id_t root_id; /* (4.5.1.1) */
unsigned int root_path_cost; /* (4.5.1.2) */
bridge_id_t bridge_id; /* (4.5.1.3) */
unsigned short port_id; /* (4.5.1.4) */
unsigned short message_age; /* (4.5.1.5) */
unsigned short max_age; /* (4.5.1.6) */
unsigned short hello_time; /* (4.5.1.7) */
unsigned short forward_delay; /* (4.5.1.8) */
} Config_bpdu;
/** Topology Change Notification BPDU Parameters (4.5.2) **/
typedef struct {
unsigned short protocol_id;
unsigned char protocol_version_id;
unsigned char type;
} Tcn_bpdu;
#define BPDU_TYPE_CONFIG 0
#define BPDU_TYPE_TOPO_CHANGE 128
/** Bridge Parameters (4.5.3) **/
typedef struct {
bridge_id_t designated_root; /* (4.5.3.1) */
unsigned int root_path_cost; /* (4.5.3.2) */
unsigned int root_port; /* (4.5.3.3) */
unsigned short max_age; /* (4.5.3.4) */
unsigned short hello_time; /* (4.5.3.5) */
unsigned short forward_delay; /* (4.5.3.6) */
bridge_id_t bridge_id; /* (4.5.3.7) */
unsigned short bridge_max_age; /* (4.5.3.8) */
unsigned short bridge_hello_time; /* (4.5.3.9) */
unsigned short bridge_forward_delay; /* (4.5.3.10) */
unsigned int topology_change_detected; /* (4.5.3.11) */
unsigned int topology_change; /* (4.5.3.12) */
unsigned short topology_change_time; /* (4.5.3.13) */
unsigned short hold_time; /* (4.5.3.14) */
unsigned int top_change;
unsigned int top_change_detected;
} Bridge_data;
/** Port Parameters (4.5.5) **/
typedef struct {
unsigned short port_id; /* (4.5.5.1) */
unsigned int state; /* (4.5.5.2) */
unsigned int path_cost; /* (4.5.5.3) */
bridge_id_t designated_root; /* (4.5.5.4) */
unsigned int designated_cost; /* (4.5.5.5) */
bridge_id_t designated_bridge; /* (4.5.5.6) */
unsigned short designated_port; /* (4.5.5.7) */
unsigned int top_change_ack; /* (4.5.5.8) */
unsigned int config_pending; /* (4.5.5.9) */
struct device *dev;
struct fdb *fdb; /* head of per port fdb chain */
} Port_data;
/** types to support timers for this pseudo-implementation. **/
typedef struct {
unsigned int active; /* timer in use. */
unsigned int value; /* current value of timer,
* counting up. */
} Timer;
struct fdb {
unsigned char ula[6];
unsigned char pad[2];
unsigned short port;
unsigned int timer;
unsigned int flags;
#define FDB_ENT_VALID 0x01
/* AVL tree of all addresses, sorted by address */
short fdb_avl_height;
struct fdb *fdb_avl_left;
struct fdb *fdb_avl_right;
/* linked list of addresses for each port */
struct fdb *fdb_next;
};
#define IS_BRIDGED 0x2e
struct br_stat {
unsigned int flags;
Bridge_data bridge_data;
Port_data port_data[No_of_ports];
};
/* defined flags for br_stat.flags */
#define BR_UP 0x0001 /* bridging enabled */
#define BR_DEBUG 0x0002 /* debugging enabled */
struct br_cf {
unsigned int cmd;
unsigned int arg1;
unsigned int arg2;
};
/* defined cmds */
#define BRCMD_BRIDGE_ENABLE 1
#define BRCMD_BRIDGE_DISABLE 2
#define BRCMD_PORT_ENABLE 3 /* arg1 = port */
#define BRCMD_PORT_DISABLE 4 /* arg1 = port */
#define BRCMD_SET_BRIDGE_PRIORITY 5 /* arg1 = priority */
#define BRCMD_SET_PORT_PRIORITY 6 /* arg1 = port, arg2 = priority */
#define BRCMD_SET_PATH_COST 7 /* arg1 = port, arg2 = cost */
#define BRCMD_DISPLAY_FDB 8 /* arg1 = port */
#define BRCMD_ENABLE_DEBUG 9
#define BRCMD_DISABLE_DEBUG 10
/* prototypes of all bridging functions... */
void transmit_config(int port_no);
int root_bridge(void);
int supersedes_port_info(int port_no, Config_bpdu *config);
void record_config_information(int port_no, Config_bpdu *config);
void record_config_timeout_values(Config_bpdu *config);
void config_bpdu_generation(void);
int designated_port(int port_no);
void reply(int port_no);
void transmit_tcn(void);
void configuration_update(void);
void root_selection(void);
void designated_port_selection(void);
void become_designated_port(int port_no);
void port_state_selection(void);
void make_forwarding(int port_no);
void topology_change_detection(void);
void topology_change_acknowledged(void);
void acknowledge_topology_change(int port_no);
void make_blocking(int port_no);
void set_port_state(int port_no, int state);
void received_config_bpdu(int port_no, Config_bpdu *config);
void received_tcn_bpdu(int port_no, Tcn_bpdu *tcn);
void hello_timer_expiry(void);
void message_age_timer_expiry(int port_no);
void forward_delay_timer_expiry(int port_no);
int designated_for_some_port(void);
void tcn_timer_expiry(void);
void topology_change_timer_expiry(void);
void hold_timer_expiry(int port_no);
void br_init(void);
void br_init_port(int port_no);
void enable_port(int port_no);
void disable_port(int port_no);
void set_bridge_priority(bridge_id_t *new_bridge_id);
void set_port_priority(int port_no, unsigned short new_port_id);
void set_path_cost(int port_no, unsigned short path_cost);
void start_hello_timer(void);
void stop_hello_timer(void);
int hello_timer_expired(void);
void start_tcn_timer(void);
void stop_tcn_timer(void);
int tcn_timer_expired(void);
void start_topology_change_timer(void);
void stop_topology_change_timer(void);
int topology_change_timer_expired(void);
void start_message_age_timer(int port_no, unsigned short message_age);
void stop_message_age_timer(int port_no);
int message_age_timer_expired(int port_no);
void start_forward_delay_timer(int port_no);
void stop_forward_delay_timer(int port_no);
int forward_delay_timer_expired(int port_no);
void start_hold_timer(int port_no);
void stop_hold_timer(int port_no);
int hold_timer_expired(int port_no);
struct fdb *br_avl_find_addr(unsigned char addr[6]);
int br_avl_insert (struct fdb * new_node);
int br_avl_remove (struct fdb * node_to_delete);
int send_tcn_bpdu(int port_no, Tcn_bpdu *bpdu);
int send_config_bpdu(int port_no, Config_bpdu *config_bpdu);
int find_port(struct device *dev);
int br_flood(struct sk_buff *skb, int port);
int br_drop(struct sk_buff *skb);
int br_learn(struct sk_buff *skb, int port); /* 3.8 */
int br_receive_frame(struct sk_buff *skb); /* 3.5 */
int br_tx_frame(struct sk_buff *skb);
int br_ioctl(unsigned int cmd, void *arg);
void free_fdb(struct fdb *);
struct fdb *get_fdb(void);
/* externs */
extern struct br_stat br_stats;
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