[mirror_frr.git] / isisd / isis_bfd.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * IS-IS Rout(e)ing protocol - BFD support
 * Copyright (C) 2018 Christian Franke
 */
#include <zebra.h>

#include "zclient.h"
#include "nexthop.h"
#include "bfd.h"
#include "lib_errors.h"

#include "isisd/isis_bfd.h"
#include "isisd/isis_zebra.h"
#include "isisd/isis_common.h"
#include "isisd/isis_constants.h"
#include "isisd/isis_adjacency.h"
#include "isisd/isis_circuit.h"
#include "isisd/isisd.h"
#include "isisd/fabricd.h"

DEFINE_MTYPE_STATIC(ISISD, BFD_SESSION, "ISIS BFD Session");

static void adj_bfd_cb(struct bfd_session_params *bsp,
		       const struct bfd_session_status *bss, void *arg)
{
	struct isis_adjacency *adj = arg;

	if (IS_DEBUG_BFD)
		zlog_debug(
			"ISIS-BFD: BFD changed status for adjacency %s old %s new %s",
			isis_adj_name(adj),
			bfd_get_status_str(bss->previous_state),
			bfd_get_status_str(bss->state));

	if (bss->state == BFD_STATUS_DOWN
	    && bss->previous_state == BFD_STATUS_UP) {
		adj->circuit->area->bfd_signalled_down = true;
		isis_adj_state_change(&adj, ISIS_ADJ_DOWN,
				      "bfd session went down");
	}
}

static void bfd_handle_adj_down(struct isis_adjacency *adj)
{
	bfd_sess_free(&adj->bfd_session);
}

static void bfd_handle_adj_up(struct isis_adjacency *adj)
{
	struct isis_circuit *circuit = adj->circuit;
	int family;
	union g_addr dst_ip;
	union g_addr src_ip;
	struct list *local_ips;
	struct prefix *local_ip;

	if (!circuit->bfd_config.enabled) {
		if (IS_DEBUG_BFD)
			zlog_debug(
				"ISIS-BFD: skipping BFD initialization on adjacency with %s because BFD is not enabled for the circuit",
				isis_adj_name(adj));
		goto out;
	}

	/* If IS-IS IPv6 is configured wait for IPv6 address to be programmed
	 * before starting up BFD
	 */
	if (circuit->ipv6_router
	    && (listcount(circuit->ipv6_link) == 0
		|| adj->ll_ipv6_count == 0)) {
		if (IS_DEBUG_BFD)
			zlog_debug(
				"ISIS-BFD: skipping BFD initialization on adjacency with %s because IPv6 is enabled but not ready",
				isis_adj_name(adj));
		return;
	}

	/*
	 * If IS-IS is enabled for both IPv4 and IPv6 on the circuit, prefer
	 * creating a BFD session over IPv6.
	 */
	if (circuit->ipv6_router && adj->ll_ipv6_count) {
		family = AF_INET6;
		dst_ip.ipv6 = adj->ll_ipv6_addrs[0];
		local_ips = circuit->ipv6_link;
		if (list_isempty(local_ips)) {
			if (IS_DEBUG_BFD)
				zlog_debug(
					"ISIS-BFD: skipping BFD initialization: IPv6 enabled and no local IPv6 addresses");
			goto out;
		}
		local_ip = listgetdata(listhead(local_ips));
		src_ip.ipv6 = local_ip->u.prefix6;
	} else if (circuit->ip_router && adj->ipv4_address_count) {
		family = AF_INET;
		dst_ip.ipv4 = adj->ipv4_addresses[0];
		local_ips = fabricd_ip_addrs(adj->circuit);
		if (!local_ips || list_isempty(local_ips)) {
			if (IS_DEBUG_BFD)
				zlog_debug(
					"ISIS-BFD: skipping BFD initialization: IPv4 enabled and no local IPv4 addresses");
			goto out;
		}
		local_ip = listgetdata(listhead(local_ips));
		src_ip.ipv4 = local_ip->u.prefix4;
	} else
		goto out;

	if (adj->bfd_session == NULL)
		adj->bfd_session = bfd_sess_new(adj_bfd_cb, adj);

	bfd_sess_set_timers(adj->bfd_session, BFD_DEF_DETECT_MULT,
			    BFD_DEF_MIN_RX, BFD_DEF_MIN_TX);
	if (family == AF_INET)
		bfd_sess_set_ipv4_addrs(adj->bfd_session, &src_ip.ipv4,
					&dst_ip.ipv4);
	else
		bfd_sess_set_ipv6_addrs(adj->bfd_session, &src_ip.ipv6,
					&dst_ip.ipv6);
	bfd_sess_set_interface(adj->bfd_session, adj->circuit->interface->name);
	bfd_sess_set_vrf(adj->bfd_session,
			 adj->circuit->interface->vrf->vrf_id);
	bfd_sess_set_profile(adj->bfd_session, circuit->bfd_config.profile);
	bfd_sess_install(adj->bfd_session);
	return;
out:
	bfd_handle_adj_down(adj);
}

static int bfd_handle_adj_state_change(struct isis_adjacency *adj)
{
	if (adj->adj_state == ISIS_ADJ_UP)
		bfd_handle_adj_up(adj);
	else
		bfd_handle_adj_down(adj);
	return 0;
}

static void bfd_adj_cmd(struct isis_adjacency *adj)
{
	if (adj->adj_state == ISIS_ADJ_UP && adj->circuit->bfd_config.enabled)
		bfd_handle_adj_up(adj);
	else
		bfd_handle_adj_down(adj);
}

void isis_bfd_circuit_cmd(struct isis_circuit *circuit)
{
	switch (circuit->circ_type) {
	case CIRCUIT_T_BROADCAST:
		for (int level = ISIS_LEVEL1; level <= ISIS_LEVEL2; level++) {
			struct list *adjdb = circuit->u.bc.adjdb[level - 1];

			struct listnode *node;
			struct isis_adjacency *adj;

			if (!adjdb)
				continue;
			for (ALL_LIST_ELEMENTS_RO(adjdb, node, adj))
				bfd_adj_cmd(adj);
		}
		break;
	case CIRCUIT_T_P2P:
		if (circuit->u.p2p.neighbor)
			bfd_adj_cmd(circuit->u.p2p.neighbor);
		break;
	default:
		break;
	}
}

static int bfd_handle_adj_ip_enabled(struct isis_adjacency *adj, int family,
				     bool global)
{

	if (family != AF_INET6 || global)
		return 0;

	if (adj->bfd_session)
		return 0;

	if (adj->adj_state != ISIS_ADJ_UP)
		return 0;

	bfd_handle_adj_up(adj);

	return 0;
}

static int bfd_handle_circuit_add_addr(struct isis_circuit *circuit)
{
	struct isis_adjacency *adj;
	struct listnode *node;

	if (circuit->area == NULL)
		return 0;

	for (ALL_LIST_ELEMENTS_RO(circuit->area->adjacency_list, node, adj)) {
		if (adj->bfd_session)
			continue;

		if (adj->adj_state != ISIS_ADJ_UP)
			continue;

		bfd_handle_adj_up(adj);
	}

	return 0;
}

void isis_bfd_init(struct thread_master *tm)
{
	bfd_protocol_integration_init(zclient, tm);

	hook_register(isis_adj_state_change_hook, bfd_handle_adj_state_change);
	hook_register(isis_adj_ip_enabled_hook, bfd_handle_adj_ip_enabled);
	hook_register(isis_circuit_add_addr_hook, bfd_handle_circuit_add_addr);
}
Commit	Line	Data
acddc0ed	1	// SPDX-License-Identifier: GPL-2.0-or-later
52df8228 CF	2	/*
52df8228 CF	3	* IS-IS Rout(e)ing protocol - BFD support
52df8228	4	* Copyright (C) 2018 Christian Franke
52df8228 CF	5	*/
	6	#include <zebra.h>
	7
	8	#include "zclient.h"
e782cca7	9	#include "nexthop.h"
52df8228	10	#include "bfd.h"
e782cca7	11	#include "lib_errors.h"
52df8228 CF	12
	13	#include "isisd/isis_bfd.h"
	14	#include "isisd/isis_zebra.h"
215eccb0 CF	15	#include "isisd/isis_common.h"
	16	#include "isisd/isis_constants.h"
	17	#include "isisd/isis_adjacency.h"
	18	#include "isisd/isis_circuit.h"
3015e3d1	19	#include "isisd/isisd.h"
215eccb0	20	#include "isisd/fabricd.h"
52df8228	21
bf8d3d6a	22	DEFINE_MTYPE_STATIC(ISISD, BFD_SESSION, "ISIS BFD Session");
20a42f01	23
13bf3830 IR	24	static void adj_bfd_cb(struct bfd_session_params *bsp,
13bf3830 IR	25	const struct bfd_session_status bss, void arg)
52df8228	26	{
13bf3830	27	struct isis_adjacency *adj = arg;
ab880eaf	28
e740f9c1	29	if (IS_DEBUG_BFD)
13bf3830 IR	30	zlog_debug(
	31	"ISIS-BFD: BFD changed status for adjacency %s old %s new %s",
	32	isis_adj_name(adj),
	33	bfd_get_status_str(bss->previous_state),
	34	bfd_get_status_str(bss->state));
bb99eb5d	35
13bf3830 IR	36	if (bss->state == BFD_STATUS_DOWN
	37	&& bss->previous_state == BFD_STATUS_UP) {
	38	adj->circuit->area->bfd_signalled_down = true;
	39	isis_adj_state_change(&adj, ISIS_ADJ_DOWN,
	40	"bfd session went down");
bb99eb5d	41	}
bb99eb5d G	42	}
bb99eb5d G	43
20a42f01 CF	44	static void bfd_handle_adj_down(struct isis_adjacency *adj)
20a42f01 CF	45	{
13bf3830	46	bfd_sess_free(&adj->bfd_session);
20a42f01 CF	47	}
20a42f01 CF	48
13bf3830	49	static void bfd_handle_adj_up(struct isis_adjacency *adj)
215eccb0	50	{
20a42f01	51	struct isis_circuit *circuit = adj->circuit;
e782cca7 RW	52	int family;
	53	union g_addr dst_ip;
	54	union g_addr src_ip;
	55	struct list *local_ips;
	56	struct prefix *local_ip;
20a42f01	57
13bf3830	58	if (!circuit->bfd_config.enabled) {
980390ce EDP	59	if (IS_DEBUG_BFD)
980390ce EDP	60	zlog_debug(
13bf3830	61	"ISIS-BFD: skipping BFD initialization on adjacency with %s because BFD is not enabled for the circuit",
980390ce	62	isis_adj_name(adj));
20a42f01	63	goto out;
980390ce	64	}
20a42f01	65
2bec0447 KS	66	/* If IS-IS IPv6 is configured wait for IPv6 address to be programmed
	67	* before starting up BFD
	68	*/
0d5b1a3a EDP	69	if (circuit->ipv6_router
0d5b1a3a EDP	70	&& (listcount(circuit->ipv6_link) == 0
173f8887	71	\|\| adj->ll_ipv6_count == 0)) {
0d5b1a3a EDP	72	if (IS_DEBUG_BFD)
	73	zlog_debug(
	74	"ISIS-BFD: skipping BFD initialization on adjacency with %s because IPv6 is enabled but not ready",
	75	isis_adj_name(adj));
2bec0447	76	return;
0d5b1a3a	77	}
2bec0447	78
e782cca7 RW	79	/*
	80	* If IS-IS is enabled for both IPv4 and IPv6 on the circuit, prefer
	81	* creating a BFD session over IPv6.
	82	*/
173f8887	83	if (circuit->ipv6_router && adj->ll_ipv6_count) {
e782cca7	84	family = AF_INET6;
173f8887	85	dst_ip.ipv6 = adj->ll_ipv6_addrs[0];
e782cca7	86	local_ips = circuit->ipv6_link;
91a5bbc4	87	if (list_isempty(local_ips)) {
980390ce EDP	88	if (IS_DEBUG_BFD)
	89	zlog_debug(
	90	"ISIS-BFD: skipping BFD initialization: IPv6 enabled and no local IPv6 addresses");
e782cca7	91	goto out;
980390ce	92	}
e782cca7 RW	93	local_ip = listgetdata(listhead(local_ips));
	94	src_ip.ipv6 = local_ip->u.prefix6;
	95	} else if (circuit->ip_router && adj->ipv4_address_count) {
	96	family = AF_INET;
	97	dst_ip.ipv4 = adj->ipv4_addresses[0];
	98	local_ips = fabricd_ip_addrs(adj->circuit);
980390ce EDP	99	if (!local_ips \|\| list_isempty(local_ips)) {
	100	if (IS_DEBUG_BFD)
	101	zlog_debug(
	102	"ISIS-BFD: skipping BFD initialization: IPv4 enabled and no local IPv4 addresses");
e782cca7	103	goto out;
980390ce	104	}
e782cca7 RW	105	local_ip = listgetdata(listhead(local_ips));
	106	src_ip.ipv4 = local_ip->u.prefix4;
	107	} else
20a42f01 CF	108	goto out;
20a42f01 CF	109
13bf3830 IR	110	if (adj->bfd_session == NULL)
13bf3830 IR	111	adj->bfd_session = bfd_sess_new(adj_bfd_cb, adj);
bb99eb5d	112
13bf3830 IR	113	bfd_sess_set_timers(adj->bfd_session, BFD_DEF_DETECT_MULT,
	114	BFD_DEF_MIN_RX, BFD_DEF_MIN_TX);
	115	if (family == AF_INET)
	116	bfd_sess_set_ipv4_addrs(adj->bfd_session, &src_ip.ipv4,
	117	&dst_ip.ipv4);
	118	else
	119	bfd_sess_set_ipv6_addrs(adj->bfd_session, &src_ip.ipv6,
	120	&dst_ip.ipv6);
	121	bfd_sess_set_interface(adj->bfd_session, adj->circuit->interface->name);
096f7609 IR	122	bfd_sess_set_vrf(adj->bfd_session,
096f7609 IR	123	adj->circuit->interface->vrf->vrf_id);
13bf3830 IR	124	bfd_sess_set_profile(adj->bfd_session, circuit->bfd_config.profile);
13bf3830 IR	125	bfd_sess_install(adj->bfd_session);
215eccb0	126	return;
20a42f01 CF	127	out:
	128	bfd_handle_adj_down(adj);
	129	}
	130
	131	static int bfd_handle_adj_state_change(struct isis_adjacency *adj)
	132	{
	133	if (adj->adj_state == ISIS_ADJ_UP)
13bf3830	134	bfd_handle_adj_up(adj);
20a42f01 CF	135	else
	136	bfd_handle_adj_down(adj);
	137	return 0;
	138	}
	139
13bf3830	140	static void bfd_adj_cmd(struct isis_adjacency *adj)
20a42f01	141	{
13bf3830 IR	142	if (adj->adj_state == ISIS_ADJ_UP && adj->circuit->bfd_config.enabled)
	143	bfd_handle_adj_up(adj);
	144	else
20a42f01	145	bfd_handle_adj_down(adj);
20a42f01 CF	146	}
20a42f01 CF	147
13bf3830	148	void isis_bfd_circuit_cmd(struct isis_circuit *circuit)
20a42f01 CF	149	{
	150	switch (circuit->circ_type) {
	151	case CIRCUIT_T_BROADCAST:
	152	for (int level = ISIS_LEVEL1; level <= ISIS_LEVEL2; level++) {
	153	struct list *adjdb = circuit->u.bc.adjdb[level - 1];
	154
	155	struct listnode *node;
	156	struct isis_adjacency *adj;
5489eb45	157
a514ac48 PG	158	if (!adjdb)
a514ac48 PG	159	continue;
20a42f01	160	for (ALL_LIST_ELEMENTS_RO(adjdb, node, adj))
13bf3830	161	bfd_adj_cmd(adj);
20a42f01 CF	162	}
	163	break;
	164	case CIRCUIT_T_P2P:
	165	if (circuit->u.p2p.neighbor)
13bf3830	166	bfd_adj_cmd(circuit->u.p2p.neighbor);
20a42f01 CF	167	break;
	168	default:
	169	break;
	170	}
215eccb0 CF	171	}
215eccb0 CF	172
173f8887 OD	173	static int bfd_handle_adj_ip_enabled(struct isis_adjacency *adj, int family,
173f8887 OD	174	bool global)
2bec0447 KS	175	{
2bec0447 KS	176
173f8887	177	if (family != AF_INET6 \|\| global)
2bec0447 KS	178	return 0;
	179
	180	if (adj->bfd_session)
	181	return 0;
	182
	183	if (adj->adj_state != ISIS_ADJ_UP)
	184	return 0;
	185
13bf3830	186	bfd_handle_adj_up(adj);
2bec0447 KS	187
	188	return 0;
	189	}
	190
	191	static int bfd_handle_circuit_add_addr(struct isis_circuit *circuit)
	192	{
	193	struct isis_adjacency *adj;
	194	struct listnode *node;
	195
9d3de36d	196	if (circuit->area == NULL)
2bec0447 KS	197	return 0;
	198
	199	for (ALL_LIST_ELEMENTS_RO(circuit->area->adjacency_list, node, adj)) {
	200	if (adj->bfd_session)
	201	continue;
	202
	203	if (adj->adj_state != ISIS_ADJ_UP)
	204	continue;
	205
13bf3830	206	bfd_handle_adj_up(adj);
2bec0447 KS	207	}
	208
	209	return 0;
	210	}
	211
13bf3830	212	void isis_bfd_init(struct thread_master *tm)
52df8228	213	{
13bf3830 IR	214	bfd_protocol_integration_init(zclient, tm);
	215
	216	hook_register(isis_adj_state_change_hook, bfd_handle_adj_state_change);
2bec0447 KS	217	hook_register(isis_adj_ip_enabled_hook, bfd_handle_adj_ip_enabled);
2bec0447 KS	218	hook_register(isis_circuit_add_addr_hook, bfd_handle_circuit_add_addr);
52df8228	219	}