[mirror_frr.git] / nhrpd / nhrp_cache.c

/* NHRP cache
 * Copyright (c) 2014-2015 Timo Teräs
 *
 * This file is free software: you may copy, redistribute 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 "zebra.h"
#include "memory.h"
#include "thread.h"
#include "hash.h"
#include "nhrpd.h"

#include "netlink.h"

DEFINE_MTYPE_STATIC(NHRPD, NHRP_CACHE, "NHRP cache entry")

unsigned long nhrp_cache_counts[NHRP_CACHE_NUM_TYPES];

const char * const nhrp_cache_type_str[] = {
	[NHRP_CACHE_INVALID]	= "invalid",
	[NHRP_CACHE_INCOMPLETE]	= "incomplete",
	[NHRP_CACHE_NEGATIVE]	= "negative",
	[NHRP_CACHE_CACHED]	= "cached",
	[NHRP_CACHE_DYNAMIC]	= "dynamic",
	[NHRP_CACHE_NHS]	= "nhs",
	[NHRP_CACHE_STATIC]	= "static",
	[NHRP_CACHE_LOCAL]	= "local",
};

static unsigned int nhrp_cache_protocol_key(void *peer_data)
{
	struct nhrp_cache *p = peer_data;
	return sockunion_hash(&p->remote_addr);
}

static int nhrp_cache_protocol_cmp(const void *cache_data, const void *key_data)
{
	const struct nhrp_cache *a = cache_data;
	const struct nhrp_cache *b = key_data;
	return sockunion_same(&a->remote_addr, &b->remote_addr);
}

static void *nhrp_cache_alloc(void *data)
{
	struct nhrp_cache *p, *key = data;

	p = XMALLOC(MTYPE_NHRP_CACHE, sizeof(struct nhrp_cache));
	if (p) {
		*p = (struct nhrp_cache) {
			.cur.type = NHRP_CACHE_INVALID,
			.new.type = NHRP_CACHE_INVALID,
			.remote_addr = key->remote_addr,
			.ifp = key->ifp,
			.notifier_list = NOTIFIER_LIST_INITIALIZER(&p->notifier_list),
		};
		nhrp_cache_counts[p->cur.type]++;
	}

	return p;
}

static void nhrp_cache_free(struct nhrp_cache *c)
{
	struct nhrp_interface *nifp = c->ifp->info;

	zassert(c->cur.type == NHRP_CACHE_INVALID && c->cur.peer == NULL);
	zassert(c->new.type == NHRP_CACHE_INVALID && c->new.peer == NULL);
	nhrp_cache_counts[c->cur.type]--;
	notifier_call(&c->notifier_list, NOTIFY_CACHE_DELETE);
	zassert(!notifier_active(&c->notifier_list));
	hash_release(nifp->cache_hash, c);
	XFREE(MTYPE_NHRP_CACHE, c);
}

struct nhrp_cache *nhrp_cache_get(struct interface *ifp, union sockunion *remote_addr, int create)
{
	struct nhrp_interface *nifp = ifp->info;
	struct nhrp_cache key;

	if (!nifp->cache_hash) {
		nifp->cache_hash = hash_create(nhrp_cache_protocol_key, nhrp_cache_protocol_cmp, NULL);
		if (!nifp->cache_hash)
			return NULL;
	}

	key.remote_addr = *remote_addr;
	key.ifp = ifp;

	return hash_get(nifp->cache_hash, &key, create ? nhrp_cache_alloc : NULL);
}

static int nhrp_cache_do_free(struct thread *t)
{
	struct nhrp_cache *c = THREAD_ARG(t);
	c->t_timeout = NULL;
	nhrp_cache_free(c);
	return 0;
}

static int nhrp_cache_do_timeout(struct thread *t)
{
	struct nhrp_cache *c = THREAD_ARG(t);
	c->t_timeout = NULL;
	if (c->cur.type != NHRP_CACHE_INVALID)
		nhrp_cache_update_binding(c, c->cur.type, -1, NULL, 0, NULL);
	return 0;
}

static void nhrp_cache_update_route(struct nhrp_cache *c)
{
	struct prefix pfx;
	struct nhrp_peer *p = c->cur.peer;

	sockunion2hostprefix(&c->remote_addr, &pfx);

	if (p && nhrp_peer_check(p, 1)) {
		netlink_update_binding(p->ifp, &c->remote_addr, &p->vc->remote.nbma);
		nhrp_route_announce(1, c->cur.type, &pfx, c->ifp, NULL, c->cur.mtu);
		if (c->cur.type >= NHRP_CACHE_DYNAMIC) {
			nhrp_route_update_nhrp(&pfx, c->ifp);
			c->nhrp_route_installed = 1;
		} else if (c->nhrp_route_installed) {
			nhrp_route_update_nhrp(&pfx, NULL);
			c->nhrp_route_installed = 0;
		}
		if (!c->route_installed) {
			notifier_call(&c->notifier_list, NOTIFY_CACHE_UP);
			c->route_installed = 1;
		}
	} else {
		if (c->nhrp_route_installed) {
			nhrp_route_update_nhrp(&pfx, NULL);
			c->nhrp_route_installed = 0;
		}
		if (c->route_installed) {
			sockunion2hostprefix(&c->remote_addr, &pfx);
			notifier_call(&c->notifier_list, NOTIFY_CACHE_DOWN);
			nhrp_route_announce(0, c->cur.type, &pfx, NULL, NULL, 0);
			c->route_installed = 0;
		}
	}
}

static void nhrp_cache_peer_notifier(struct notifier_block *n, unsigned long cmd)
{
	struct nhrp_cache *c = container_of(n, struct nhrp_cache, peer_notifier);

	switch (cmd) {
	case NOTIFY_PEER_UP:
		nhrp_cache_update_route(c);
		break;
	case NOTIFY_PEER_DOWN:
	case NOTIFY_PEER_IFCONFIG_CHANGED:
		notifier_call(&c->notifier_list, NOTIFY_CACHE_DOWN);
		nhrp_cache_update_binding(c, c->cur.type, -1, NULL, 0, NULL);
		break;
	case NOTIFY_PEER_NBMA_CHANGING:
		if (c->cur.type == NHRP_CACHE_DYNAMIC)
			c->cur.peer->vc->abort_migration = 1;
		break;
	}
}

static void nhrp_cache_reset_new(struct nhrp_cache *c)
{
	THREAD_OFF(c->t_auth);
	if (list_hashed(&c->newpeer_notifier.notifier_entry))
		nhrp_peer_notify_del(c->new.peer, &c->newpeer_notifier);
	nhrp_peer_unref(c->new.peer);
	memset(&c->new, 0, sizeof(c->new));
	c->new.type = NHRP_CACHE_INVALID;
}

static void nhrp_cache_update_timers(struct nhrp_cache *c)
{
	THREAD_OFF(c->t_timeout);

	switch (c->cur.type) {
	case NHRP_CACHE_INVALID:
		if (!c->t_auth)
			thread_add_timer_msec(master, nhrp_cache_do_free, c,
					      10, &c->t_timeout);
		break;
	default:
		if (c->cur.expires)
			thread_add_timer(master, nhrp_cache_do_timeout, c,
					 c->cur.expires - monotime(NULL),
					 &c->t_timeout);
		break;
	}
}

static void nhrp_cache_authorize_binding(struct nhrp_reqid *r, void *arg)
{
	struct nhrp_cache *c = container_of(r, struct nhrp_cache, eventid);
	char buf[SU_ADDRSTRLEN];

	debugf(NHRP_DEBUG_COMMON, "cache: %s %s: %s",
		c->ifp->name, sockunion2str(&c->remote_addr, buf, sizeof buf),
		(const char *) arg);

	nhrp_reqid_free(&nhrp_event_reqid, r);

	if (arg && strcmp(arg, "accept") == 0) {
		if (c->cur.peer) {
			netlink_update_binding(c->cur.peer->ifp, &c->remote_addr, NULL);
			nhrp_peer_notify_del(c->cur.peer, &c->peer_notifier);
			nhrp_peer_unref(c->cur.peer);
		}
		nhrp_cache_counts[c->cur.type]--;
		nhrp_cache_counts[c->new.type]++;
		c->cur = c->new;
		c->cur.peer = nhrp_peer_ref(c->cur.peer);
		nhrp_cache_reset_new(c);
		if (c->cur.peer)
			nhrp_peer_notify_add(c->cur.peer, &c->peer_notifier, nhrp_cache_peer_notifier);
		nhrp_cache_update_route(c);
		notifier_call(&c->notifier_list, NOTIFY_CACHE_BINDING_CHANGE);
	} else {
		nhrp_cache_reset_new(c);
	}

	nhrp_cache_update_timers(c);
}

static int nhrp_cache_do_auth_timeout(struct thread *t)
{
	struct nhrp_cache *c = THREAD_ARG(t);
	c->t_auth = NULL;
	nhrp_cache_authorize_binding(&c->eventid, (void *) "timeout");
	return 0;
}

static void nhrp_cache_newpeer_notifier(struct notifier_block *n, unsigned long cmd)
{
	struct nhrp_cache *c = container_of(n, struct nhrp_cache, newpeer_notifier);

	switch (cmd) {
	case NOTIFY_PEER_UP:
		if (nhrp_peer_check(c->new.peer, 1)) {
			evmgr_notify("authorize-binding", c, nhrp_cache_authorize_binding);
			thread_add_timer(master, nhrp_cache_do_auth_timeout,
					 c, 10, &c->t_auth);
		}
		break;
	case NOTIFY_PEER_DOWN:
	case NOTIFY_PEER_IFCONFIG_CHANGED:
		nhrp_cache_reset_new(c);
		break;
	}
}

int nhrp_cache_update_binding(struct nhrp_cache *c, enum nhrp_cache_type type, int holding_time, struct nhrp_peer *p, uint32_t mtu, union sockunion *nbma_oa)
{
	if (c->cur.type > type || c->new.type > type) {
		nhrp_peer_unref(p);
		return 0;
	}

	/* Sanitize MTU */
	switch (sockunion_family(&c->remote_addr)) {
	case AF_INET:
		if (mtu < 576 || mtu >= 1500)
			mtu = 0;
		/* Opennhrp announces nbma mtu, but we use protocol mtu.
		 * This heuristic tries to fix up it. */
		if (mtu > 1420) mtu = (mtu & -16) - 80;
		break;
	default:
		mtu = 0;
		break;
	}

	nhrp_cache_reset_new(c);
	if (c->cur.type == type && c->cur.peer == p && c->cur.mtu == mtu) {
		if (holding_time > 0) c->cur.expires = monotime(NULL) + holding_time;
		if (nbma_oa) c->cur.remote_nbma_natoa = *nbma_oa;
		else memset(&c->cur.remote_nbma_natoa, 0, sizeof c->cur.remote_nbma_natoa);
		nhrp_peer_unref(p);
	} else {
		c->new.type = type;
		c->new.peer = p;
		c->new.mtu = mtu;
		if (nbma_oa) c->new.remote_nbma_natoa = *nbma_oa;

		if (holding_time > 0)
			c->new.expires = monotime(NULL) + holding_time;
		else if (holding_time < 0)
			nhrp_cache_reset_new(c);

		if (c->new.type == NHRP_CACHE_INVALID ||
		    c->new.type >= NHRP_CACHE_STATIC ||
		    c->map) {
			nhrp_cache_authorize_binding(&c->eventid, (void *) "accept");
		} else {
			nhrp_peer_notify_add(c->new.peer, &c->newpeer_notifier, nhrp_cache_newpeer_notifier);
			nhrp_cache_newpeer_notifier(&c->newpeer_notifier, NOTIFY_PEER_UP);
			thread_add_timer(master, nhrp_cache_do_auth_timeout,
					 c, 60, &c->t_auth);
		}
	}
	nhrp_cache_update_timers(c);

	return 1;
}

void nhrp_cache_set_used(struct nhrp_cache *c, int used)
{
	c->used = used;
	if (c->used)
		notifier_call(&c->notifier_list, NOTIFY_CACHE_USED);
}

struct nhrp_cache_iterator_ctx {
	void (*cb)(struct nhrp_cache *, void *);
	void *ctx;
};

static void nhrp_cache_iterator(struct hash_backet *b, void *ctx)
{
	struct nhrp_cache_iterator_ctx *ic = ctx;
	ic->cb(b->data, ic->ctx);
}

void nhrp_cache_foreach(struct interface *ifp, void (*cb)(struct nhrp_cache *, void *), void *ctx)
{
	struct nhrp_interface *nifp = ifp->info;
	struct nhrp_cache_iterator_ctx ic = {
		.cb = cb,
		.ctx = ctx,
	};

	if (nifp->cache_hash)
		hash_iterate(nifp->cache_hash, nhrp_cache_iterator, &ic);
}

void nhrp_cache_notify_add(struct nhrp_cache *c, struct notifier_block *n, notifier_fn_t fn)
{
	notifier_add(n, &c->notifier_list, fn);
}

void nhrp_cache_notify_del(struct nhrp_cache *c, struct notifier_block *n)
{
	notifier_del(n);
}
Commit	Line	Data
2fb975da TT	1	/* NHRP cache
	2	* Copyright (c) 2014-2015 Timo Teräs
	3	*
	4	* This file is free software: you may copy, redistribute and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation, either version 2 of the License, or
	7	* (at your option) any later version.
	8	*/
	9
	10	#include "zebra.h"
	11	#include "memory.h"
	12	#include "thread.h"
	13	#include "hash.h"
	14	#include "nhrpd.h"
	15
	16	#include "netlink.h"
	17
819dc8bb DL	18	DEFINE_MTYPE_STATIC(NHRPD, NHRP_CACHE, "NHRP cache entry")
819dc8bb DL	19
2fb975da TT	20	unsigned long nhrp_cache_counts[NHRP_CACHE_NUM_TYPES];
	21
	22	const char * const nhrp_cache_type_str[] = {
	23	[NHRP_CACHE_INVALID] = "invalid",
	24	[NHRP_CACHE_INCOMPLETE] = "incomplete",
	25	[NHRP_CACHE_NEGATIVE] = "negative",
	26	[NHRP_CACHE_CACHED] = "cached",
	27	[NHRP_CACHE_DYNAMIC] = "dynamic",
	28	[NHRP_CACHE_NHS] = "nhs",
	29	[NHRP_CACHE_STATIC] = "static",
	30	[NHRP_CACHE_LOCAL] = "local",
	31	};
	32
	33	static unsigned int nhrp_cache_protocol_key(void *peer_data)
	34	{
	35	struct nhrp_cache *p = peer_data;
	36	return sockunion_hash(&p->remote_addr);
	37	}
	38
	39	static int nhrp_cache_protocol_cmp(const void cache_data, const void key_data)
	40	{
	41	const struct nhrp_cache *a = cache_data;
	42	const struct nhrp_cache *b = key_data;
	43	return sockunion_same(&a->remote_addr, &b->remote_addr);
	44	}
	45
	46	static void nhrp_cache_alloc(void data)
	47	{
	48	struct nhrp_cache p, key = data;
	49
	50	p = XMALLOC(MTYPE_NHRP_CACHE, sizeof(struct nhrp_cache));
	51	if (p) {
	52	*p = (struct nhrp_cache) {
	53	.cur.type = NHRP_CACHE_INVALID,
	54	.new.type = NHRP_CACHE_INVALID,
	55	.remote_addr = key->remote_addr,
	56	.ifp = key->ifp,
	57	.notifier_list = NOTIFIER_LIST_INITIALIZER(&p->notifier_list),
	58	};
	59	nhrp_cache_counts[p->cur.type]++;
	60	}
	61
	62	return p;
	63	}
	64
	65	static void nhrp_cache_free(struct nhrp_cache *c)
	66	{
	67	struct nhrp_interface *nifp = c->ifp->info;
	68
	69	zassert(c->cur.type == NHRP_CACHE_INVALID && c->cur.peer == NULL);
	70	zassert(c->new.type == NHRP_CACHE_INVALID && c->new.peer == NULL);
	71	nhrp_cache_counts[c->cur.type]--;
	72	notifier_call(&c->notifier_list, NOTIFY_CACHE_DELETE);
	73	zassert(!notifier_active(&c->notifier_list));
	74	hash_release(nifp->cache_hash, c);
	75	XFREE(MTYPE_NHRP_CACHE, c);
	76	}
	77
	78	struct nhrp_cache nhrp_cache_get(struct interface ifp, union sockunion *remote_addr, int create)
	79	{
	80	struct nhrp_interface *nifp = ifp->info;
	81	struct nhrp_cache key;
	82
	83	if (!nifp->cache_hash) {
dfd19ccc	84	nifp->cache_hash = hash_create(nhrp_cache_protocol_key, nhrp_cache_protocol_cmp, NULL);
2fb975da TT	85	if (!nifp->cache_hash)
	86	return NULL;
	87	}
	88
	89	key.remote_addr = *remote_addr;
	90	key.ifp = ifp;
	91
	92	return hash_get(nifp->cache_hash, &key, create ? nhrp_cache_alloc : NULL);
	93	}
	94
	95	static int nhrp_cache_do_free(struct thread *t)
	96	{
	97	struct nhrp_cache *c = THREAD_ARG(t);
	98	c->t_timeout = NULL;
	99	nhrp_cache_free(c);
	100	return 0;
	101	}
	102
	103	static int nhrp_cache_do_timeout(struct thread *t)
	104	{
	105	struct nhrp_cache *c = THREAD_ARG(t);
	106	c->t_timeout = NULL;
	107	if (c->cur.type != NHRP_CACHE_INVALID)
	108	nhrp_cache_update_binding(c, c->cur.type, -1, NULL, 0, NULL);
	109	return 0;
	110	}
	111
	112	static void nhrp_cache_update_route(struct nhrp_cache *c)
	113	{
	114	struct prefix pfx;
	115	struct nhrp_peer *p = c->cur.peer;
	116
	117	sockunion2hostprefix(&c->remote_addr, &pfx);
	118
	119	if (p && nhrp_peer_check(p, 1)) {
	120	netlink_update_binding(p->ifp, &c->remote_addr, &p->vc->remote.nbma);
	121	nhrp_route_announce(1, c->cur.type, &pfx, c->ifp, NULL, c->cur.mtu);
	122	if (c->cur.type >= NHRP_CACHE_DYNAMIC) {
	123	nhrp_route_update_nhrp(&pfx, c->ifp);
	124	c->nhrp_route_installed = 1;
	125	} else if (c->nhrp_route_installed) {
	126	nhrp_route_update_nhrp(&pfx, NULL);
	127	c->nhrp_route_installed = 0;
	128	}
	129	if (!c->route_installed) {
	130	notifier_call(&c->notifier_list, NOTIFY_CACHE_UP);
	131	c->route_installed = 1;
	132	}
	133	} else {
	134	if (c->nhrp_route_installed) {
	135	nhrp_route_update_nhrp(&pfx, NULL);
	136	c->nhrp_route_installed = 0;
	137	}
	138	if (c->route_installed) {
	139	sockunion2hostprefix(&c->remote_addr, &pfx);
	140	notifier_call(&c->notifier_list, NOTIFY_CACHE_DOWN);
	141	nhrp_route_announce(0, c->cur.type, &pfx, NULL, NULL, 0);
	142	c->route_installed = 0;
	143	}
	144	}
	145	}
	146
	147	static void nhrp_cache_peer_notifier(struct notifier_block *n, unsigned long cmd)
	148	{
149	struct nhrp_cache *c = container_of(n, struct nhrp_cache, peer_notifier);
150
151	switch (cmd) {
152	case NOTIFY_PEER_UP:
153	nhrp_cache_update_route(c);
154	break;
155	case NOTIFY_PEER_DOWN:
156	case NOTIFY_PEER_IFCONFIG_CHANGED:
157	notifier_call(&c->notifier_list, NOTIFY_CACHE_DOWN);
158	nhrp_cache_update_binding(c, c->cur.type, -1, NULL, 0, NULL);
159	break;
160	case NOTIFY_PEER_NBMA_CHANGING:
161	if (c->cur.type == NHRP_CACHE_DYNAMIC)
162	c->cur.peer->vc->abort_migration = 1;
163	break;
164	}
165	}
166
167	static void nhrp_cache_reset_new(struct nhrp_cache *c)
168	{
169	THREAD_OFF(c->t_auth);
170	if (list_hashed(&c->newpeer_notifier.notifier_entry))
171	nhrp_peer_notify_del(c->new.peer, &c->newpeer_notifier);
172	nhrp_peer_unref(c->new.peer);
173	memset(&c->new, 0, sizeof(c->new));
174	c->new.type = NHRP_CACHE_INVALID;
175	}
176
177	static void nhrp_cache_update_timers(struct nhrp_cache *c)
178	{
179	THREAD_OFF(c->t_timeout);
180
181	switch (c->cur.type) {
182	case NHRP_CACHE_INVALID:
183	if (!c->t_auth)
ffa2c898 QY	184	thread_add_timer_msec(master, nhrp_cache_do_free, c,
ffa2c898 QY	185	10, &c->t_timeout);
2fb975da TT	186	break;
	187	default:
	188	if (c->cur.expires)
ffa2c898 QY	189	thread_add_timer(master, nhrp_cache_do_timeout, c,
	190	c->cur.expires - monotime(NULL),
	191	&c->t_timeout);
2fb975da TT	192	break;
	193	}
	194	}
	195
	196	static void nhrp_cache_authorize_binding(struct nhrp_reqid r, void arg)
	197	{
	198	struct nhrp_cache *c = container_of(r, struct nhrp_cache, eventid);
	199	char buf[SU_ADDRSTRLEN];
	200
	201	debugf(NHRP_DEBUG_COMMON, "cache: %s %s: %s",
	202	c->ifp->name, sockunion2str(&c->remote_addr, buf, sizeof buf),
	203	(const char *) arg);
	204
	205	nhrp_reqid_free(&nhrp_event_reqid, r);
	206
	207	if (arg && strcmp(arg, "accept") == 0) {
	208	if (c->cur.peer) {
	209	netlink_update_binding(c->cur.peer->ifp, &c->remote_addr, NULL);
	210	nhrp_peer_notify_del(c->cur.peer, &c->peer_notifier);
	211	nhrp_peer_unref(c->cur.peer);
	212	}
	213	nhrp_cache_counts[c->cur.type]--;
	214	nhrp_cache_counts[c->new.type]++;
	215	c->cur = c->new;
	216	c->cur.peer = nhrp_peer_ref(c->cur.peer);
	217	nhrp_cache_reset_new(c);
	218	if (c->cur.peer)
	219	nhrp_peer_notify_add(c->cur.peer, &c->peer_notifier, nhrp_cache_peer_notifier);
	220	nhrp_cache_update_route(c);
	221	notifier_call(&c->notifier_list, NOTIFY_CACHE_BINDING_CHANGE);
	222	} else {
	223	nhrp_cache_reset_new(c);
	224	}
	225
	226	nhrp_cache_update_timers(c);
	227	}
	228
	229	static int nhrp_cache_do_auth_timeout(struct thread *t)
	230	{
	231	struct nhrp_cache *c = THREAD_ARG(t);
	232	c->t_auth = NULL;
	233	nhrp_cache_authorize_binding(&c->eventid, (void *) "timeout");
	234	return 0;
	235	}
	236
	237	static void nhrp_cache_newpeer_notifier(struct notifier_block *n, unsigned long cmd)
	238	{
	239	struct nhrp_cache *c = container_of(n, struct nhrp_cache, newpeer_notifier);
	240
	241	switch (cmd) {
	242	case NOTIFY_PEER_UP:
	243	if (nhrp_peer_check(c->new.peer, 1)) {
	244	evmgr_notify("authorize-binding", c, nhrp_cache_authorize_binding);
ffa2c898 QY	245	thread_add_timer(master, nhrp_cache_do_auth_timeout,
ffa2c898 QY	246	c, 10, &c->t_auth);
2fb975da TT	247	}
	248	break;
	249	case NOTIFY_PEER_DOWN:
	250	case NOTIFY_PEER_IFCONFIG_CHANGED:
	251	nhrp_cache_reset_new(c);
	252	break;
	253	}
	254	}
	255
	256	int nhrp_cache_update_binding(struct nhrp_cache c, enum nhrp_cache_type type, int holding_time, struct nhrp_peer p, uint32_t mtu, union sockunion *nbma_oa)
	257	{
	258	if (c->cur.type > type \|\| c->new.type > type) {
	259	nhrp_peer_unref(p);
	260	return 0;
	261	}
	262
	263	/* Sanitize MTU */
	264	switch (sockunion_family(&c->remote_addr)) {
	265	case AF_INET:
	266	if (mtu < 576 \|\| mtu >= 1500)
	267	mtu = 0;
	268	/* Opennhrp announces nbma mtu, but we use protocol mtu.
	269	* This heuristic tries to fix up it. */
	270	if (mtu > 1420) mtu = (mtu & -16) - 80;
	271	break;
	272	default:
	273	mtu = 0;
	274	break;
	275	}
	276
	277	nhrp_cache_reset_new(c);
	278	if (c->cur.type == type && c->cur.peer == p && c->cur.mtu == mtu) {
819dc8bb	279	if (holding_time > 0) c->cur.expires = monotime(NULL) + holding_time;
2fb975da TT	280	if (nbma_oa) c->cur.remote_nbma_natoa = *nbma_oa;
	281	else memset(&c->cur.remote_nbma_natoa, 0, sizeof c->cur.remote_nbma_natoa);
	282	nhrp_peer_unref(p);
	283	} else {
	284	c->new.type = type;
	285	c->new.peer = p;
	286	c->new.mtu = mtu;
	287	if (nbma_oa) c->new.remote_nbma_natoa = *nbma_oa;
	288
	289	if (holding_time > 0)
819dc8bb	290	c->new.expires = monotime(NULL) + holding_time;
2fb975da	291	else if (holding_time < 0)
45c8b07a	292	nhrp_cache_reset_new(c);
2fb975da TT	293
	294	if (c->new.type == NHRP_CACHE_INVALID \|\|
	295	c->new.type >= NHRP_CACHE_STATIC \|\|
	296	c->map) {
	297	nhrp_cache_authorize_binding(&c->eventid, (void *) "accept");
	298	} else {
	299	nhrp_peer_notify_add(c->new.peer, &c->newpeer_notifier, nhrp_cache_newpeer_notifier);
	300	nhrp_cache_newpeer_notifier(&c->newpeer_notifier, NOTIFY_PEER_UP);
ffa2c898 QY	301	thread_add_timer(master, nhrp_cache_do_auth_timeout,
ffa2c898 QY	302	c, 60, &c->t_auth);
2fb975da TT	303	}
	304	}
	305	nhrp_cache_update_timers(c);
	306
	307	return 1;
	308	}
	309
	310	void nhrp_cache_set_used(struct nhrp_cache *c, int used)
	311	{
	312	c->used = used;
	313	if (c->used)
	314	notifier_call(&c->notifier_list, NOTIFY_CACHE_USED);
	315	}
	316
	317	struct nhrp_cache_iterator_ctx {
	318	void (cb)(struct nhrp_cache , void *);
	319	void *ctx;
	320	};
	321
	322	static void nhrp_cache_iterator(struct hash_backet b, void ctx)
	323	{
	324	struct nhrp_cache_iterator_ctx *ic = ctx;
	325	ic->cb(b->data, ic->ctx);
	326	}
	327
	328	void nhrp_cache_foreach(struct interface ifp, void (cb)(struct nhrp_cache , void ), void *ctx)
	329	{
	330	struct nhrp_interface *nifp = ifp->info;
	331	struct nhrp_cache_iterator_ctx ic = {
	332	.cb = cb,
	333	.ctx = ctx,
	334	};
	335
	336	if (nifp->cache_hash)
	337	hash_iterate(nifp->cache_hash, nhrp_cache_iterator, &ic);
	338	}
	339
	340	void nhrp_cache_notify_add(struct nhrp_cache c, struct notifier_block n, notifier_fn_t fn)
	341	{
	342	notifier_add(n, &c->notifier_list, fn);
	343	}
	344
	345	void nhrp_cache_notify_del(struct nhrp_cache c, struct notifier_block n)
	346	{
	347	notifier_del(n);
	348	}