[mirror_frr.git] / isisd / isis_bfd.c

/*
 * IS-IS Rout(e)ing protocol - BFD support
 * Copyright (C) 2018 Christian Franke
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; see the file COPYING; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */
#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")

struct bfd_session {
	int family;
	union g_addr dst_ip;
	union g_addr src_ip;
	int status;
};

static struct bfd_session *bfd_session_new(int family, union g_addr *dst_ip,
					   union g_addr *src_ip)
{
	struct bfd_session *rv;

	rv = XCALLOC(MTYPE_BFD_SESSION, sizeof(*rv));
	rv->family = family;
	rv->dst_ip = *dst_ip;
	rv->src_ip = *src_ip;
	return rv;
}

static void bfd_session_free(struct bfd_session **session)
{
	if (!*session)
		return;

	XFREE(MTYPE_BFD_SESSION, *session);
}

static bool bfd_session_same(const struct bfd_session *session, int family,
			     const union g_addr *src, const union g_addr *dst)
{
	if (session->family != family)
		return false;

	switch (session->family) {
	case AF_INET:
		if (!IPV4_ADDR_SAME(&session->dst_ip.ipv4, &dst->ipv4))
			return false;
		if (!IPV4_ADDR_SAME(&session->src_ip.ipv4, &src->ipv4))
			return false;
		break;
	case AF_INET6:
		if (!IPV6_ADDR_SAME(&session->dst_ip.ipv6, &dst->ipv6))
			return false;
		if (!IPV6_ADDR_SAME(&session->src_ip.ipv6, &src->ipv6))
			return false;
		break;
	default:
		flog_err(EC_LIB_DEVELOPMENT, "%s: unknown address-family: %u",
			 __func__, session->family);
		exit(1);
	}

	return true;
}

static void bfd_adj_event(struct isis_adjacency *adj, struct prefix *dst,
			  int new_status)
{
	if (!adj->bfd_session)
		return;

	if (adj->bfd_session->family != dst->family)
		return;

	switch (adj->bfd_session->family) {
	case AF_INET:
		if (!IPV4_ADDR_SAME(&adj->bfd_session->dst_ip.ipv4,
				    &dst->u.prefix4))
			return;
		break;
	case AF_INET6:
		if (!IPV6_ADDR_SAME(&adj->bfd_session->dst_ip.ipv6,
				    &dst->u.prefix6))
			return;
		break;
	default:
		flog_err(EC_LIB_DEVELOPMENT, "%s: unknown address-family: %u",
			 __func__, adj->bfd_session->family);
		exit(1);
	}

	int old_status = adj->bfd_session->status;

	BFD_SET_CLIENT_STATUS(adj->bfd_session->status, new_status);

	if (old_status == new_status)
		return;

	if (IS_DEBUG_BFD) {
		char dst_str[INET6_ADDRSTRLEN];

		inet_ntop(adj->bfd_session->family, &adj->bfd_session->dst_ip,
			  dst_str, sizeof(dst_str));
		zlog_debug("ISIS-BFD: Peer %s on %s changed from %s to %s",
			   dst_str, adj->circuit->interface->name,
			   bfd_get_status_str(old_status),
			   bfd_get_status_str(new_status));
	}

	if (old_status != BFD_STATUS_UP
	    || new_status != BFD_STATUS_DOWN) {
		return;
	}

	adj->circuit->area->bfd_signalled_down = true;

	isis_adj_state_change(&adj, ISIS_ADJ_DOWN, "bfd session went down");
}

static int isis_bfd_interface_dest_update(ZAPI_CALLBACK_ARGS)
{
	struct interface *ifp;
	struct prefix dst_ip;
	int status;

	ifp = bfd_get_peer_info(zclient->ibuf, &dst_ip, NULL, &status,
				NULL, vrf_id);
	if (!ifp || (dst_ip.family != AF_INET && dst_ip.family != AF_INET6))
		return 0;

	if (IS_DEBUG_BFD) {
		char dst_buf[INET6_ADDRSTRLEN];

		inet_ntop(dst_ip.family, &dst_ip.u.prefix, dst_buf,
			  sizeof(dst_buf));

		zlog_debug("ISIS-BFD: Received update for %s on %s: Changed state to %s",
			   dst_buf, ifp->name, bfd_get_status_str(status));
	}

	struct isis_circuit *circuit = circuit_scan_by_ifp(ifp);

	if (!circuit)
		return 0;

	if (circuit->circ_type == CIRCUIT_T_BROADCAST) {
		for (int level = ISIS_LEVEL1; level <= ISIS_LEVEL2; level++) {
			struct list *adjdb = circuit->u.bc.adjdb[level - 1];

			struct listnode *node, *nnode;
			struct isis_adjacency *adj;

			for (ALL_LIST_ELEMENTS(adjdb, node, nnode, adj))
				bfd_adj_event(adj, &dst_ip, status);
		}
	} else if (circuit->circ_type == CIRCUIT_T_P2P) {
		if (circuit->u.p2p.neighbor) {
			bfd_adj_event(circuit->u.p2p.neighbor,
				      &dst_ip, status);
		}
	}

	return 0;
}

static int isis_bfd_nbr_replay(ZAPI_CALLBACK_ARGS)
{
	bfd_client_sendmsg(zclient, ZEBRA_BFD_CLIENT_REGISTER, vrf_id);

	struct listnode *anode;
	struct isis_area *area;

	if (IS_DEBUG_BFD)
		zlog_debug("ISIS-BFD: Got neighbor replay request, resending neighbors.");

	for (ALL_LIST_ELEMENTS_RO(isis->area_list, anode, area)) {
		struct listnode *cnode;
		struct isis_circuit *circuit;

		for (ALL_LIST_ELEMENTS_RO(area->circuit_list, cnode, circuit))
			isis_bfd_circuit_cmd(circuit, ZEBRA_BFD_DEST_UPDATE);
	}

	if (IS_DEBUG_BFD)
		zlog_debug("ISIS-BFD: Done with replay.");

	return 0;
}

static void (*orig_zebra_connected)(struct zclient *);
static void isis_bfd_zebra_connected(struct zclient *zclient)
{
	if (orig_zebra_connected)
		orig_zebra_connected(zclient);

	bfd_client_sendmsg(zclient, ZEBRA_BFD_CLIENT_REGISTER, VRF_DEFAULT);
}

static void bfd_debug(int family, union g_addr *dst, union g_addr *src,
		      const char *interface, int command)
{
	if (!(IS_DEBUG_BFD))
		return;

	char dst_str[INET6_ADDRSTRLEN];
	char src_str[INET6_ADDRSTRLEN];

	inet_ntop(family, dst, dst_str, sizeof(dst_str));
	inet_ntop(family, src, src_str, sizeof(src_str));

	const char *command_str;

	switch (command) {
	case ZEBRA_BFD_DEST_REGISTER:
		command_str = "Register";
		break;
	case ZEBRA_BFD_DEST_DEREGISTER:
		command_str = "Deregister";
		break;
	case ZEBRA_BFD_DEST_UPDATE:
		command_str = "Update";
		break;
	default:
		command_str = "Unknown-Cmd";
		break;
	}

	zlog_debug("ISIS-BFD: %s peer %s on %s (src %s)",
		   command_str, dst_str, interface, src_str);
}

static void bfd_handle_adj_down(struct isis_adjacency *adj)
{
	if (!adj->bfd_session)
		return;

	bfd_debug(adj->bfd_session->family, &adj->bfd_session->dst_ip,
		  &adj->bfd_session->src_ip, adj->circuit->interface->name,
		  ZEBRA_BFD_DEST_DEREGISTER);

	bfd_peer_sendmsg(zclient, NULL, adj->bfd_session->family,
			 &adj->bfd_session->dst_ip, &adj->bfd_session->src_ip,
			 (adj->circuit->interface)
				 ? adj->circuit->interface->name
				 : NULL,
			 0, /* ttl */
			 0, /* multihop */
			 1, /* control plane independent bit is on */
			 ZEBRA_BFD_DEST_DEREGISTER,
			 0, /* set_flag */
			 VRF_DEFAULT);
	bfd_session_free(&adj->bfd_session);
}

static void bfd_handle_adj_up(struct isis_adjacency *adj, int command)
{
	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_info)
		goto out;

	/*
	 * 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->ipv6_address_count) {
		family = AF_INET6;
		dst_ip.ipv6 = adj->ipv6_addresses[0];
		local_ips = circuit->ipv6_link;
		if (!local_ips || list_isempty(local_ips))
			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))
			goto out;
		local_ip = listgetdata(listhead(local_ips));
		src_ip.ipv4 = local_ip->u.prefix4;
	} else
		goto out;

	if (adj->bfd_session) {
		if (bfd_session_same(adj->bfd_session, family, &src_ip,
				     &dst_ip))
			bfd_handle_adj_down(adj);
	}

	if (!adj->bfd_session)
		adj->bfd_session = bfd_session_new(family, &dst_ip, &src_ip);

	bfd_debug(adj->bfd_session->family, &adj->bfd_session->dst_ip,
		  &adj->bfd_session->src_ip, circuit->interface->name, command);
	bfd_peer_sendmsg(zclient, circuit->bfd_info, adj->bfd_session->family,
			 &adj->bfd_session->dst_ip,
			 &adj->bfd_session->src_ip,
			 (adj->circuit->interface)
				 ? adj->circuit->interface->name
				 : NULL,
			 0, /* ttl */
			 0, /* multihop */
			 1, /* control plane independent bit is on */
			 command,
			 0, /* set flag */
			 VRF_DEFAULT);
	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, ZEBRA_BFD_DEST_REGISTER);
	else
		bfd_handle_adj_down(adj);
	return 0;
}

static void bfd_adj_cmd(struct isis_adjacency *adj, int command)
{
	if (adj->adj_state == ISIS_ADJ_UP
	    && command != ZEBRA_BFD_DEST_DEREGISTER) {
		bfd_handle_adj_up(adj, command);
	} else {
		bfd_handle_adj_down(adj);
	}
}

void isis_bfd_circuit_cmd(struct isis_circuit *circuit, int command)
{
	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;

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

void isis_bfd_circuit_param_set(struct isis_circuit *circuit, uint32_t min_rx,
				uint32_t min_tx, uint32_t detect_mult,
				const char *profile, int defaults)
{
	int command = 0;

	bfd_set_param(&circuit->bfd_info, min_rx, min_tx, detect_mult, profile,
		      defaults, &command);

	if (command)
		isis_bfd_circuit_cmd(circuit, command);
}

#ifdef FABRICD
static int bfd_circuit_write_settings(struct isis_circuit *circuit,
				      struct vty *vty)
{
	struct bfd_info *bfd_info = circuit->bfd_info;

	if (!bfd_info)
		return 0;

	vty_out(vty, " %s bfd\n", PROTO_NAME);
	return 1;
}
#endif

void isis_bfd_init(void)
{
	bfd_gbl_init();

	orig_zebra_connected = zclient->zebra_connected;
	zclient->zebra_connected = isis_bfd_zebra_connected;
	zclient->interface_bfd_dest_update = isis_bfd_interface_dest_update;
	zclient->bfd_dest_replay = isis_bfd_nbr_replay;
	hook_register(isis_adj_state_change_hook,
		      bfd_handle_adj_state_change);
#ifdef FABRICD
	hook_register(isis_circuit_config_write,
		      bfd_circuit_write_settings);
#endif
}
Commit	Line	Data
52df8228 CF	1	/*
52df8228 CF	2	* IS-IS Rout(e)ing protocol - BFD support
52df8228 CF	3	* Copyright (C) 2018 Christian Franke
52df8228 CF	4	*
d04f9fbf CF	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of the GNU General Public License as published by the Free
	7	* Software Foundation; either version 2 of the License, or (at your option)
	8	* any later version.
52df8228	9	*
d04f9fbf CF	10	* This program is distributed in the hope that it will be useful, but WITHOUT
	11	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	12	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	13	* more details.
52df8228 CF	14	*
	15	* You should have received a copy of the GNU General Public License along
	16	* with this program; see the file COPYING; if not, write to the Free Software
	17	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	18	*/
	19	#include <zebra.h>
	20
	21	#include "zclient.h"
e782cca7	22	#include "nexthop.h"
52df8228	23	#include "bfd.h"
e782cca7	24	#include "lib_errors.h"
52df8228 CF	25
	26	#include "isisd/isis_bfd.h"
	27	#include "isisd/isis_zebra.h"
215eccb0 CF	28	#include "isisd/isis_common.h"
	29	#include "isisd/isis_constants.h"
	30	#include "isisd/isis_adjacency.h"
	31	#include "isisd/isis_circuit.h"
3015e3d1	32	#include "isisd/isisd.h"
215eccb0	33	#include "isisd/fabricd.h"
52df8228	34
20a42f01 CF	35	DEFINE_MTYPE_STATIC(ISISD, BFD_SESSION, "ISIS BFD Session")
	36
	37	struct bfd_session {
e782cca7 RW	38	int family;
	39	union g_addr dst_ip;
	40	union g_addr src_ip;
a5eba4e9	41	int status;
20a42f01 CF	42	};
20a42f01 CF	43
e782cca7 RW	44	static struct bfd_session bfd_session_new(int family, union g_addr dst_ip,
e782cca7 RW	45	union g_addr *src_ip)
20a42f01 CF	46	{
	47	struct bfd_session *rv;
	48
a5eba4e9	49	rv = XCALLOC(MTYPE_BFD_SESSION, sizeof(*rv));
e782cca7	50	rv->family = family;
20a42f01 CF	51	rv->dst_ip = *dst_ip;
	52	rv->src_ip = *src_ip;
	53	return rv;
	54	}
	55
	56	static void bfd_session_free(struct bfd_session **session)
	57	{
	58	if (!*session)
	59	return;
	60
	61	XFREE(MTYPE_BFD_SESSION, *session);
20a42f01 CF	62	}
20a42f01 CF	63
e782cca7 RW	64	static bool bfd_session_same(const struct bfd_session *session, int family,
	65	const union g_addr src, const union g_addr dst)
	66	{
	67	if (session->family != family)
	68	return false;
	69
	70	switch (session->family) {
	71	case AF_INET:
	72	if (!IPV4_ADDR_SAME(&session->dst_ip.ipv4, &dst->ipv4))
	73	return false;
	74	if (!IPV4_ADDR_SAME(&session->src_ip.ipv4, &src->ipv4))
	75	return false;
	76	break;
	77	case AF_INET6:
	78	if (!IPV6_ADDR_SAME(&session->dst_ip.ipv6, &dst->ipv6))
	79	return false;
	80	if (!IPV6_ADDR_SAME(&session->src_ip.ipv6, &src->ipv6))
	81	return false;
	82	break;
	83	default:
	84	flog_err(EC_LIB_DEVELOPMENT, "%s: unknown address-family: %u",
	85	__func__, session->family);
	86	exit(1);
	87	}
	88
	89	return true;
	90	}
	91
a5eba4e9 CF	92	static void bfd_adj_event(struct isis_adjacency adj, struct prefix dst,
	93	int new_status)
	94	{
	95	if (!adj->bfd_session)
	96	return;
	97
e782cca7	98	if (adj->bfd_session->family != dst->family)
a5eba4e9 CF	99	return;
a5eba4e9 CF	100
e782cca7 RW	101	switch (adj->bfd_session->family) {
	102	case AF_INET:
	103	if (!IPV4_ADDR_SAME(&adj->bfd_session->dst_ip.ipv4,
	104	&dst->u.prefix4))
	105	return;
	106	break;
	107	case AF_INET6:
	108	if (!IPV6_ADDR_SAME(&adj->bfd_session->dst_ip.ipv6,
	109	&dst->u.prefix6))
	110	return;
	111	break;
	112	default:
	113	flog_err(EC_LIB_DEVELOPMENT, "%s: unknown address-family: %u",
	114	__func__, adj->bfd_session->family);
	115	exit(1);
	116	}
	117
a5eba4e9	118	int old_status = adj->bfd_session->status;
a5eba4e9	119
7555dc61 S	120	BFD_SET_CLIENT_STATUS(adj->bfd_session->status, new_status);
7555dc61 S	121
a5eba4e9 CF	122	if (old_status == new_status)
	123	return;
	124
e740f9c1	125	if (IS_DEBUG_BFD) {
a5eba4e9 CF	126	char dst_str[INET6_ADDRSTRLEN];
a5eba4e9 CF	127
e782cca7	128	inet_ntop(adj->bfd_session->family, &adj->bfd_session->dst_ip,
a5eba4e9 CF	129	dst_str, sizeof(dst_str));
	130	zlog_debug("ISIS-BFD: Peer %s on %s changed from %s to %s",
	131	dst_str, adj->circuit->interface->name,
	132	bfd_get_status_str(old_status),
	133	bfd_get_status_str(new_status));
	134	}
	135
	136	if (old_status != BFD_STATUS_UP
	137	\|\| new_status != BFD_STATUS_DOWN) {
	138	return;
	139	}
	140
690497fb G	141	adj->circuit->area->bfd_signalled_down = true;
690497fb G	142
16167b31	143	isis_adj_state_change(&adj, ISIS_ADJ_DOWN, "bfd session went down");
a5eba4e9 CF	144	}
a5eba4e9 CF	145
121f9dee	146	static int isis_bfd_interface_dest_update(ZAPI_CALLBACK_ARGS)
52df8228	147	{
2815f817 CF	148	struct interface *ifp;
	149	struct prefix dst_ip;
	150	int status;
	151
9beff0bd PG	152	ifp = bfd_get_peer_info(zclient->ibuf, &dst_ip, NULL, &status,
9beff0bd PG	153	NULL, vrf_id);
e782cca7	154	if (!ifp \|\| (dst_ip.family != AF_INET && dst_ip.family != AF_INET6))
2815f817 CF	155	return 0;
2815f817 CF	156
e740f9c1	157	if (IS_DEBUG_BFD) {
2815f817	158	char dst_buf[INET6_ADDRSTRLEN];
5489eb45	159
e782cca7 RW	160	inet_ntop(dst_ip.family, &dst_ip.u.prefix, dst_buf,
e782cca7 RW	161	sizeof(dst_buf));
2815f817 CF	162
	163	zlog_debug("ISIS-BFD: Received update for %s on %s: Changed state to %s",
	164	dst_buf, ifp->name, bfd_get_status_str(status));
	165	}
	166
a5eba4e9	167	struct isis_circuit *circuit = circuit_scan_by_ifp(ifp);
5489eb45	168
a5eba4e9 CF	169	if (!circuit)
	170	return 0;
	171
	172	if (circuit->circ_type == CIRCUIT_T_BROADCAST) {
	173	for (int level = ISIS_LEVEL1; level <= ISIS_LEVEL2; level++) {
	174	struct list *adjdb = circuit->u.bc.adjdb[level - 1];
	175
	176	struct listnode node, nnode;
	177	struct isis_adjacency *adj;
	178
	179	for (ALL_LIST_ELEMENTS(adjdb, node, nnode, adj))
	180	bfd_adj_event(adj, &dst_ip, status);
	181	}
	182	} else if (circuit->circ_type == CIRCUIT_T_P2P) {
	183	if (circuit->u.p2p.neighbor) {
	184	bfd_adj_event(circuit->u.p2p.neighbor,
	185	&dst_ip, status);
	186	}
	187	}
	188
52df8228 CF	189	return 0;
	190	}
	191
121f9dee	192	static int isis_bfd_nbr_replay(ZAPI_CALLBACK_ARGS)
52df8228	193	{
0945d5ed	194	bfd_client_sendmsg(zclient, ZEBRA_BFD_CLIENT_REGISTER, vrf_id);
ab880eaf CF	195
	196	struct listnode *anode;
	197	struct isis_area *area;
	198
e740f9c1	199	if (IS_DEBUG_BFD)
2815f817 CF	200	zlog_debug("ISIS-BFD: Got neighbor replay request, resending neighbors.");
2815f817 CF	201
ab880eaf CF	202	for (ALL_LIST_ELEMENTS_RO(isis->area_list, anode, area)) {
	203	struct listnode *cnode;
	204	struct isis_circuit *circuit;
	205
	206	for (ALL_LIST_ELEMENTS_RO(area->circuit_list, cnode, circuit))
	207	isis_bfd_circuit_cmd(circuit, ZEBRA_BFD_DEST_UPDATE);
	208	}
	209
e740f9c1	210	if (IS_DEBUG_BFD)
2815f817 CF	211	zlog_debug("ISIS-BFD: Done with replay.");
2815f817 CF	212
52df8228 CF	213	return 0;
	214	}
	215
	216	static void (orig_zebra_connected)(struct zclient );
	217	static void isis_bfd_zebra_connected(struct zclient *zclient)
	218	{
	219	if (orig_zebra_connected)
	220	orig_zebra_connected(zclient);
	221
0945d5ed	222	bfd_client_sendmsg(zclient, ZEBRA_BFD_CLIENT_REGISTER, VRF_DEFAULT);
52df8228 CF	223	}
52df8228 CF	224
e782cca7	225	static void bfd_debug(int family, union g_addr dst, union g_addr src,
2815f817 CF	226	const char *interface, int command)
2815f817 CF	227	{
e740f9c1	228	if (!(IS_DEBUG_BFD))
2815f817 CF	229	return;
	230
	231	char dst_str[INET6_ADDRSTRLEN];
	232	char src_str[INET6_ADDRSTRLEN];
	233
e782cca7 RW	234	inet_ntop(family, dst, dst_str, sizeof(dst_str));
e782cca7 RW	235	inet_ntop(family, src, src_str, sizeof(src_str));
2815f817 CF	236
	237	const char *command_str;
	238
	239	switch (command) {
	240	case ZEBRA_BFD_DEST_REGISTER:
	241	command_str = "Register";
	242	break;
	243	case ZEBRA_BFD_DEST_DEREGISTER:
	244	command_str = "Deregister";
	245	break;
	246	case ZEBRA_BFD_DEST_UPDATE:
	247	command_str = "Update";
	248	break;
	249	default:
	250	command_str = "Unknown-Cmd";
	251	break;
	252	}
	253
	254	zlog_debug("ISIS-BFD: %s peer %s on %s (src %s)",
	255	command_str, dst_str, interface, src_str);
	256	}
	257
20a42f01 CF	258	static void bfd_handle_adj_down(struct isis_adjacency *adj)
	259	{
	260	if (!adj->bfd_session)
	261	return;
	262
e782cca7 RW	263	bfd_debug(adj->bfd_session->family, &adj->bfd_session->dst_ip,
	264	&adj->bfd_session->src_ip, adj->circuit->interface->name,
	265	ZEBRA_BFD_DEST_DEREGISTER);
2815f817	266
e782cca7	267	bfd_peer_sendmsg(zclient, NULL, adj->bfd_session->family,
c2afd32f RZ	268	&adj->bfd_session->dst_ip, &adj->bfd_session->src_ip,
	269	(adj->circuit->interface)
	270	? adj->circuit->interface->name
	271	: NULL,
20a42f01 CF	272	0, /* ttl */
20a42f01 CF	273	0, /* multihop */
9beff0bd	274	1, /* control plane independent bit is on */
20a42f01 CF	275	ZEBRA_BFD_DEST_DEREGISTER,
	276	0, /* set_flag */
	277	VRF_DEFAULT);
	278	bfd_session_free(&adj->bfd_session);
	279	}
	280
	281	static void bfd_handle_adj_up(struct isis_adjacency *adj, int command)
215eccb0	282	{
20a42f01	283	struct isis_circuit *circuit = adj->circuit;
e782cca7 RW	284	int family;
	285	union g_addr dst_ip;
	286	union g_addr src_ip;
	287	struct list *local_ips;
	288	struct prefix *local_ip;
20a42f01	289
e782cca7	290	if (!circuit->bfd_info)
20a42f01 CF	291	goto out;
20a42f01 CF	292
e782cca7 RW	293	/*
	294	* If IS-IS is enabled for both IPv4 and IPv6 on the circuit, prefer
	295	* creating a BFD session over IPv6.
	296	*/
	297	if (circuit->ipv6_router && adj->ipv6_address_count) {
	298	family = AF_INET6;
	299	dst_ip.ipv6 = adj->ipv6_addresses[0];
	300	local_ips = circuit->ipv6_link;
	301	if (!local_ips \|\| list_isempty(local_ips))
	302	goto out;
	303	local_ip = listgetdata(listhead(local_ips));
	304	src_ip.ipv6 = local_ip->u.prefix6;
	305	} else if (circuit->ip_router && adj->ipv4_address_count) {
	306	family = AF_INET;
	307	dst_ip.ipv4 = adj->ipv4_addresses[0];
	308	local_ips = fabricd_ip_addrs(adj->circuit);
	309	if (!local_ips \|\| list_isempty(local_ips))
	310	goto out;
	311	local_ip = listgetdata(listhead(local_ips));
	312	src_ip.ipv4 = local_ip->u.prefix4;
	313	} else
20a42f01 CF	314	goto out;
20a42f01 CF	315
20a42f01	316	if (adj->bfd_session) {
e782cca7 RW	317	if (bfd_session_same(adj->bfd_session, family, &src_ip,
e782cca7 RW	318	&dst_ip))
20a42f01 CF	319	bfd_handle_adj_down(adj);
	320	}
	321
	322	if (!adj->bfd_session)
e782cca7	323	adj->bfd_session = bfd_session_new(family, &dst_ip, &src_ip);
20a42f01	324
e782cca7 RW	325	bfd_debug(adj->bfd_session->family, &adj->bfd_session->dst_ip,
	326	&adj->bfd_session->src_ip, circuit->interface->name, command);
	327	bfd_peer_sendmsg(zclient, circuit->bfd_info, adj->bfd_session->family,
20a42f01 CF	328	&adj->bfd_session->dst_ip,
20a42f01 CF	329	&adj->bfd_session->src_ip,
c2afd32f RZ	330	(adj->circuit->interface)
	331	? adj->circuit->interface->name
	332	: NULL,
20a42f01 CF	333	0, /* ttl */
20a42f01 CF	334	0, /* multihop */
9beff0bd	335	1, /* control plane independent bit is on */
20a42f01 CF	336	command,
	337	0, /* set flag */
	338	VRF_DEFAULT);
215eccb0	339	return;
20a42f01 CF	340	out:
	341	bfd_handle_adj_down(adj);
	342	}
	343
	344	static int bfd_handle_adj_state_change(struct isis_adjacency *adj)
	345	{
	346	if (adj->adj_state == ISIS_ADJ_UP)
	347	bfd_handle_adj_up(adj, ZEBRA_BFD_DEST_REGISTER);
	348	else
	349	bfd_handle_adj_down(adj);
	350	return 0;
	351	}
	352
	353	static void bfd_adj_cmd(struct isis_adjacency *adj, int command)
	354	{
	355	if (adj->adj_state == ISIS_ADJ_UP
	356	&& command != ZEBRA_BFD_DEST_DEREGISTER) {
	357	bfd_handle_adj_up(adj, command);
	358	} else {
	359	bfd_handle_adj_down(adj);
	360	}
	361	}
	362
	363	void isis_bfd_circuit_cmd(struct isis_circuit *circuit, int command)
	364	{
	365	switch (circuit->circ_type) {
	366	case CIRCUIT_T_BROADCAST:
	367	for (int level = ISIS_LEVEL1; level <= ISIS_LEVEL2; level++) {
	368	struct list *adjdb = circuit->u.bc.adjdb[level - 1];
	369
	370	struct listnode *node;
	371	struct isis_adjacency *adj;
5489eb45	372
20a42f01 CF	373	for (ALL_LIST_ELEMENTS_RO(adjdb, node, adj))
	374	bfd_adj_cmd(adj, command);
	375	}
	376	break;
	377	case CIRCUIT_T_P2P:
	378	if (circuit->u.p2p.neighbor)
	379	bfd_adj_cmd(circuit->u.p2p.neighbor, command);
	380	break;
	381	default:
	382	break;
	383	}
215eccb0 CF	384	}
215eccb0 CF	385
4affdba7 G	386	void isis_bfd_circuit_param_set(struct isis_circuit *circuit, uint32_t min_rx,
	387	uint32_t min_tx, uint32_t detect_mult,
	388	const char *profile, int defaults)
215eccb0 CF	389	{
	390	int command = 0;
	391
4affdba7 G	392	bfd_set_param(&circuit->bfd_info, min_rx, min_tx, detect_mult, profile,
4affdba7 G	393	defaults, &command);
215eccb0 CF	394
	395	if (command)
	396	isis_bfd_circuit_cmd(circuit, command);
	397	}
	398
05e4ec37	399	#ifdef FABRICD
3015e3d1 CF	400	static int bfd_circuit_write_settings(struct isis_circuit *circuit,
	401	struct vty *vty)
	402	{
	403	struct bfd_info *bfd_info = circuit->bfd_info;
	404
	405	if (!bfd_info)
	406	return 0;
	407
490a6fc7	408	vty_out(vty, " %s bfd\n", PROTO_NAME);
3015e3d1 CF	409	return 1;
3015e3d1 CF	410	}
05e4ec37	411	#endif
3015e3d1	412
52df8228 CF	413	void isis_bfd_init(void)
	414	{
	415	bfd_gbl_init();
	416
	417	orig_zebra_connected = zclient->zebra_connected;
	418	zclient->zebra_connected = isis_bfd_zebra_connected;
	419	zclient->interface_bfd_dest_update = isis_bfd_interface_dest_update;
	420	zclient->bfd_dest_replay = isis_bfd_nbr_replay;
20a42f01 CF	421	hook_register(isis_adj_state_change_hook,
20a42f01 CF	422	bfd_handle_adj_state_change);
05e4ec37	423	#ifdef FABRICD
3015e3d1 CF	424	hook_register(isis_circuit_config_write,
3015e3d1 CF	425	bfd_circuit_write_settings);
05e4ec37	426	#endif
52df8228	427	}