[net-next-2.6.git] / net / bridge / br_stp_if.c

/*
 *	Spanning tree protocol; interface code
 *	Linux ethernet bridge
 *
 *	Authors:
 *	Lennert Buytenhek		<buytenh@gnu.org>
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>

#include "br_private.h"
#include "br_private_stp.h"


/* Port id is composed of priority and port number.
 * NB: least significant bits of priority are dropped to
 *     make room for more ports.
 */
static inline port_id br_make_port_id(__u8 priority, __u16 port_no)
{
	return ((u16)priority << BR_PORT_BITS)
		| (port_no & ((1<<BR_PORT_BITS)-1));
}

/* called under bridge lock */
void br_init_port(struct net_bridge_port *p)
{
	p->port_id = br_make_port_id(p->priority, p->port_no);
	br_become_designated_port(p);
	p->state = BR_STATE_BLOCKING;
	p->topology_change_ack = 0;
	p->config_pending = 0;
}

/* called under bridge lock */
void br_stp_enable_bridge(struct net_bridge *br)
{
	struct net_bridge_port *p;

	spin_lock_bh(&br->lock);
	mod_timer(&br->hello_timer, jiffies + br->hello_time);
	mod_timer(&br->gc_timer, jiffies + HZ/10);

	br_config_bpdu_generation(br);

	list_for_each_entry(p, &br->port_list, list) {
		if ((p->dev->flags & IFF_UP) && netif_carrier_ok(p->dev))
			br_stp_enable_port(p);

	}
	spin_unlock_bh(&br->lock);
}

/* NO locks held */
void br_stp_disable_bridge(struct net_bridge *br)
{
	struct net_bridge_port *p;

	spin_lock_bh(&br->lock);
	list_for_each_entry(p, &br->port_list, list) {
		if (p->state != BR_STATE_DISABLED)
			br_stp_disable_port(p);

	}

	br->topology_change = 0;
	br->topology_change_detected = 0;
	spin_unlock_bh(&br->lock);

	del_timer_sync(&br->hello_timer);
	del_timer_sync(&br->topology_change_timer);
	del_timer_sync(&br->tcn_timer);
	del_timer_sync(&br->gc_timer);
}

/* called under bridge lock */
void br_stp_enable_port(struct net_bridge_port *p)
{
	br_init_port(p);
	br_port_state_selection(p->br);
	br_log_state(p);
}

/* called under bridge lock */
void br_stp_disable_port(struct net_bridge_port *p)
{
	struct net_bridge *br = p->br;
	int wasroot;

	br_log_state(p);

	wasroot = br_is_root_bridge(br);
	br_become_designated_port(p);
	p->state = BR_STATE_DISABLED;
	p->topology_change_ack = 0;
	p->config_pending = 0;

	del_timer(&p->message_age_timer);
	del_timer(&p->forward_delay_timer);
	del_timer(&p->hold_timer);

	br_fdb_delete_by_port(br, p, 0);
	br_multicast_disable_port(p);

	br_configuration_update(br);

	br_port_state_selection(br);

	if (br_is_root_bridge(br) && !wasroot)
		br_become_root_bridge(br);
}

static void br_stp_start(struct net_bridge *br)
{
	int r;
	char *argv[] = { BR_STP_PROG, br->dev->name, "start", NULL };
	char *envp[] = { NULL };

	r = call_usermodehelper(BR_STP_PROG, argv, envp, UMH_WAIT_PROC);
	if (r == 0) {
		br->stp_enabled = BR_USER_STP;
		br_debug(br, "userspace STP started\n");
	} else {
		br->stp_enabled = BR_KERNEL_STP;
		br_debug(br, "using kernel STP\n");

		/* To start timers on any ports left in blocking */
		spin_lock_bh(&br->lock);
		br_port_state_selection(br);
		spin_unlock_bh(&br->lock);
	}
}

static void br_stp_stop(struct net_bridge *br)
{
	int r;
	char *argv[] = { BR_STP_PROG, br->dev->name, "stop", NULL };
	char *envp[] = { NULL };

	if (br->stp_enabled == BR_USER_STP) {
		r = call_usermodehelper(BR_STP_PROG, argv, envp, 1);
		br_info(br, "userspace STP stopped, return code %d\n", r);

		/* To start timers on any ports left in blocking */
		spin_lock_bh(&br->lock);
		br_port_state_selection(br);
		spin_unlock_bh(&br->lock);
	}

	br->stp_enabled = BR_NO_STP;
}

void br_stp_set_enabled(struct net_bridge *br, unsigned long val)
{
	ASSERT_RTNL();

	if (val) {
		if (br->stp_enabled == BR_NO_STP)
			br_stp_start(br);
	} else {
		if (br->stp_enabled != BR_NO_STP)
			br_stp_stop(br);
	}
}

/* called under bridge lock */
void br_stp_change_bridge_id(struct net_bridge *br, const unsigned char *addr)
{
	/* should be aligned on 2 bytes for compare_ether_addr() */
	unsigned short oldaddr_aligned[ETH_ALEN >> 1];
	unsigned char *oldaddr = (unsigned char *)oldaddr_aligned;
	struct net_bridge_port *p;
	int wasroot;

	wasroot = br_is_root_bridge(br);

	memcpy(oldaddr, br->bridge_id.addr, ETH_ALEN);
	memcpy(br->bridge_id.addr, addr, ETH_ALEN);
	memcpy(br->dev->dev_addr, addr, ETH_ALEN);

	list_for_each_entry(p, &br->port_list, list) {
		if (!compare_ether_addr(p->designated_bridge.addr, oldaddr))
			memcpy(p->designated_bridge.addr, addr, ETH_ALEN);

		if (!compare_ether_addr(p->designated_root.addr, oldaddr))
			memcpy(p->designated_root.addr, addr, ETH_ALEN);

	}

	br_configuration_update(br);
	br_port_state_selection(br);
	if (br_is_root_bridge(br) && !wasroot)
		br_become_root_bridge(br);
}

/* should be aligned on 2 bytes for compare_ether_addr() */
static const unsigned short br_mac_zero_aligned[ETH_ALEN >> 1];

/* called under bridge lock */
void br_stp_recalculate_bridge_id(struct net_bridge *br)
{
	const unsigned char *br_mac_zero =
			(const unsigned char *)br_mac_zero_aligned;
	const unsigned char *addr = br_mac_zero;
	struct net_bridge_port *p;

	/* user has chosen a value so keep it */
	if (br->flags & BR_SET_MAC_ADDR)
		return;

	list_for_each_entry(p, &br->port_list, list) {
		if (addr == br_mac_zero ||
		    memcmp(p->dev->dev_addr, addr, ETH_ALEN) < 0)
			addr = p->dev->dev_addr;

	}

	if (compare_ether_addr(br->bridge_id.addr, addr))
		br_stp_change_bridge_id(br, addr);
}

/* called under bridge lock */
void br_stp_set_bridge_priority(struct net_bridge *br, u16 newprio)
{
	struct net_bridge_port *p;
	int wasroot;

	wasroot = br_is_root_bridge(br);

	list_for_each_entry(p, &br->port_list, list) {
		if (p->state != BR_STATE_DISABLED &&
		    br_is_designated_port(p)) {
			p->designated_bridge.prio[0] = (newprio >> 8) & 0xFF;
			p->designated_bridge.prio[1] = newprio & 0xFF;
		}

	}

	br->bridge_id.prio[0] = (newprio >> 8) & 0xFF;
	br->bridge_id.prio[1] = newprio & 0xFF;
	br_configuration_update(br);
	br_port_state_selection(br);
	if (br_is_root_bridge(br) && !wasroot)
		br_become_root_bridge(br);
}

/* called under bridge lock */
void br_stp_set_port_priority(struct net_bridge_port *p, u8 newprio)
{
	port_id new_port_id = br_make_port_id(newprio, p->port_no);

	if (br_is_designated_port(p))
		p->designated_port = new_port_id;

	p->port_id = new_port_id;
	p->priority = newprio;
	if (!memcmp(&p->br->bridge_id, &p->designated_bridge, 8) &&
	    p->port_id < p->designated_port) {
		br_become_designated_port(p);
		br_port_state_selection(p->br);
	}
}

/* called under bridge lock */
void br_stp_set_path_cost(struct net_bridge_port *p, u32 path_cost)
{
	p->path_cost = path_cost;
	br_configuration_update(p->br);
	br_port_state_selection(p->br);
}

ssize_t br_show_bridge_id(char *buf, const struct bridge_id *id)
{
	return sprintf(buf, "%.2x%.2x.%.2x%.2x%.2x%.2x%.2x%.2x\n",
	       id->prio[0], id->prio[1],
	       id->addr[0], id->addr[1], id->addr[2],
	       id->addr[3], id->addr[4], id->addr[5]);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Spanning tree protocol; interface code
	3	* Linux ethernet bridge
	4	*
	5	* Authors:
	6	* Lennert Buytenhek <buytenh@gnu.org>
	7	*
1da177e4 LT	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.
	12	*/
	13
	14	#include <linux/kernel.h>
6ede2463	15	#include <linux/etherdevice.h>
11dc1f36	16	#include <linux/rtnetlink.h>
1da177e4 LT	17
	18	#include "br_private.h"
	19	#include "br_private_stp.h"
	20
	21
	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.
	25	*/
	26	static inline port_id br_make_port_id(__u8 priority, __u16 port_no)
	27	{
9d6f229f	28	return ((u16)priority << BR_PORT_BITS)
1da177e4 LT	29	\| (port_no & ((1<<BR_PORT_BITS)-1));
	30	}
	31
	32	/* called under bridge lock */
	33	void br_init_port(struct net_bridge_port *p)
	34	{
	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;
1da177e4 LT	40	}
	41
	42	/* called under bridge lock */
	43	void br_stp_enable_bridge(struct net_bridge *br)
	44	{
	45	struct net_bridge_port *p;
	46
	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);
9d6f229f	50
1da177e4 LT	51	br_config_bpdu_generation(br);
	52
	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);
	56
	57	}
	58	spin_unlock_bh(&br->lock);
	59	}
	60
	61	/* NO locks held */
	62	void br_stp_disable_bridge(struct net_bridge *br)
	63	{
	64	struct net_bridge_port *p;
	65
78872ccb	66	spin_lock_bh(&br->lock);
1da177e4 LT	67	list_for_each_entry(p, &br->port_list, list) {
	68	if (p->state != BR_STATE_DISABLED)
	69	br_stp_disable_port(p);
	70
	71	}
	72
	73	br->topology_change = 0;
	74	br->topology_change_detected = 0;
78872ccb	75	spin_unlock_bh(&br->lock);
1da177e4 LT	76
	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);
	81	}
	82
	83	/* called under bridge lock */
	84	void br_stp_enable_port(struct net_bridge_port *p)
	85	{
	86	br_init_port(p);
	87	br_port_state_selection(p->br);
28a16c97	88	br_log_state(p);
1da177e4 LT	89	}
	90
	91	/* called under bridge lock */
	92	void br_stp_disable_port(struct net_bridge_port *p)
	93	{
28a16c97	94	struct net_bridge *br = p->br;
1da177e4 LT	95	int wasroot;
1da177e4 LT	96
28a16c97	97	br_log_state(p);
1da177e4 LT	98
	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;
	104
	105	del_timer(&p->message_age_timer);
	106	del_timer(&p->forward_delay_timer);
	107	del_timer(&p->hold_timer);
	108
1a620698	109	br_fdb_delete_by_port(br, p, 0);
3fe2d7c7	110	br_multicast_disable_port(p);
1a620698	111
1da177e4 LT	112	br_configuration_update(br);
	113
	114	br_port_state_selection(br);
	115
	116	if (br_is_root_bridge(br) && !wasroot)
	117	br_become_root_bridge(br);
	118	}
	119
9cde0708 SH	120	static void br_stp_start(struct net_bridge *br)
	121	{
	122	int r;
	123	char *argv[] = { BR_STP_PROG, br->dev->name, "start", NULL };
	124	char *envp[] = { NULL };
	125
86313c48	126	r = call_usermodehelper(BR_STP_PROG, argv, envp, UMH_WAIT_PROC);
9cde0708 SH	127	if (r == 0) {
9cde0708 SH	128	br->stp_enabled = BR_USER_STP;
28a16c97	129	br_debug(br, "userspace STP started\n");
9cde0708 SH	130	} else {
9cde0708 SH	131	br->stp_enabled = BR_KERNEL_STP;
28a16c97	132	br_debug(br, "using kernel STP\n");
9cde0708 SH	133
	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);
	138	}
	139	}
	140
	141	static void br_stp_stop(struct net_bridge *br)
	142	{
	143	int r;
	144	char *argv[] = { BR_STP_PROG, br->dev->name, "stop", NULL };
	145	char *envp[] = { NULL };
	146
	147	if (br->stp_enabled == BR_USER_STP) {
	148	r = call_usermodehelper(BR_STP_PROG, argv, envp, 1);
28a16c97	149	br_info(br, "userspace STP stopped, return code %d\n", r);
9cde0708 SH	150
	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);
	155	}
	156
	157	br->stp_enabled = BR_NO_STP;
	158	}
	159
	160	void br_stp_set_enabled(struct net_bridge *br, unsigned long val)
	161	{
	162	ASSERT_RTNL();
	163
	164	if (val) {
	165	if (br->stp_enabled == BR_NO_STP)
	166	br_stp_start(br);
	167	} else {
	168	if (br->stp_enabled != BR_NO_STP)
	169	br_stp_stop(br);
	170	}
	171	}
	172
1da177e4	173	/* called under bridge lock */
4505a3ef	174	void br_stp_change_bridge_id(struct net_bridge br, const unsigned char addr)
1da177e4	175	{
19bb3506 EK	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;
1da177e4 LT	179	struct net_bridge_port *p;
	180	int wasroot;
	181
	182	wasroot = br_is_root_bridge(br);
	183
	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);
	187
	188	list_for_each_entry(p, &br->port_list, list) {
6ede2463	189	if (!compare_ether_addr(p->designated_bridge.addr, oldaddr))
1da177e4 LT	190	memcpy(p->designated_bridge.addr, addr, ETH_ALEN);
1da177e4 LT	191
6ede2463	192	if (!compare_ether_addr(p->designated_root.addr, oldaddr))
1da177e4 LT	193	memcpy(p->designated_root.addr, addr, ETH_ALEN);
	194
	195	}
	196
	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);
	201	}
	202
19bb3506 EK	203	/* should be aligned on 2 bytes for compare_ether_addr() */
19bb3506 EK	204	static const unsigned short br_mac_zero_aligned[ETH_ALEN >> 1];
1da177e4 LT	205
	206	/* called under bridge lock */
	207	void br_stp_recalculate_bridge_id(struct net_bridge *br)
	208	{
19bb3506 EK	209	const unsigned char *br_mac_zero =
19bb3506 EK	210	(const unsigned char *)br_mac_zero_aligned;
1da177e4 LT	211	const unsigned char *addr = br_mac_zero;
	212	struct net_bridge_port *p;
	213
92c0574f SH	214	/* user has chosen a value so keep it */
	215	if (br->flags & BR_SET_MAC_ADDR)
	216	return;
	217
1da177e4 LT	218	list_for_each_entry(p, &br->port_list, list) {
1da177e4 LT	219	if (addr == br_mac_zero \|\|
554c9a8e	220	memcmp(p->dev->dev_addr, addr, ETH_ALEN) < 0)
1da177e4 LT	221	addr = p->dev->dev_addr;
	222
	223	}
	224
6ede2463	225	if (compare_ether_addr(br->bridge_id.addr, addr))
1da177e4 LT	226	br_stp_change_bridge_id(br, addr);
	227	}
	228
	229	/* called under bridge lock */
	230	void br_stp_set_bridge_priority(struct net_bridge *br, u16 newprio)
	231	{
	232	struct net_bridge_port *p;
	233	int wasroot;
	234
	235	wasroot = br_is_root_bridge(br);
	236
	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;
	242	}
	243
	244	}
	245
	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);
	252	}
	253
	254	/* called under bridge lock */
	255	void br_stp_set_port_priority(struct net_bridge_port *p, u8 newprio)
	256	{
	257	port_id new_port_id = br_make_port_id(newprio, p->port_no);
	258
	259	if (br_is_designated_port(p))
	260	p->designated_port = new_port_id;
	261
	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);
	268	}
	269	}
	270
	271	/* called under bridge lock */
	272	void br_stp_set_path_cost(struct net_bridge_port *p, u32 path_cost)
	273	{
	274	p->path_cost = path_cost;
	275	br_configuration_update(p->br);
	276	br_port_state_selection(p->br);
	277	}
	278
	279	ssize_t br_show_bridge_id(char buf, const struct bridge_id id)
	280	{
	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]);
	285	}