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bird/proto/ospf/iface.c
2010-05-26 16:09:22 +02:00

812 lines
19 KiB
C

/*
* BIRD -- OSPF
*
* (c) 1999--2005 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include "ospf.h"
char *ospf_is[] = { "down", "loop", "waiting", "point-to-point", "drother",
"backup", "dr"
};
char *ospf_ism[] = { "interface up", "wait timer fired", "backup seen",
"neighbor change", "loop indicated", "unloop indicated", "interface down"
};
char *ospf_it[] = { "broadcast", "nbma", "point-to-point", "virtual link" };
static void
poll_timer_hook(timer * timer)
{
ospf_hello_send(timer, 1, NULL);
}
static void
hello_timer_hook(timer * timer)
{
ospf_hello_send(timer, 0, NULL);
}
static void
wait_timer_hook(timer * timer)
{
struct ospf_iface *ifa = (struct ospf_iface *) timer->data;
struct proto *p = &ifa->oa->po->proto;
OSPF_TRACE(D_EVENTS, "Wait timer fired on interface %s.", ifa->iface->name);
ospf_iface_sm(ifa, ISM_WAITF);
}
u32
rxbufsize(struct ospf_iface *ifa)
{
switch(ifa->rxbuf)
{
case OSPF_RXBUF_NORMAL:
return (ifa->iface->mtu * 2);
break;
case OSPF_RXBUF_LARGE:
return OSPF_MAX_PKT_SIZE;
break;
default:
return ifa->rxbuf;
break;
}
}
static int
ospf_sk_open(struct ospf_iface *ifa)
{
sock *sk;
struct proto *p = &ifa->oa->po->proto;
sk = sk_new(p->pool);
sk->type = SK_IP;
sk->dport = OSPF_PROTO;
sk->saddr = IPA_NONE;
sk->tos = IP_PREC_INTERNET_CONTROL;
sk->rx_hook = ospf_rx_hook;
sk->tx_hook = ospf_tx_hook;
sk->err_hook = ospf_err_hook;
sk->iface = ifa->iface;
sk->rbsize = rxbufsize(ifa);
sk->tbsize = ifa->iface->mtu;
sk->data = (void *) ifa;
sk->flags = SKF_LADDR_RX;
if (sk_open(sk) != 0)
goto err;
#ifdef OSPFv3
/* 12 is an offset of the checksum in an OSPF packet */
if (sk_set_ipv6_checksum(sk, 12) < 0)
goto err;
#endif
/*
* For OSPFv2: When sending a packet, it is important to have a
* proper source address. We expect that when we send one-hop
* unicast packets, OS chooses a source address according to the
* destination address (to be in the same prefix). We also expect
* that when we send multicast packets, OS uses the source address
* from sk->saddr registered to OS by sk_setup_multicast(). This
* behavior is needed to implement multiple virtual ifaces (struct
* ospf_iface) on one physical iface and is signalized by
* CONFIG_MC_PROPER_SRC.
*
* If this behavior is not available (for example on BSD), we create
* non-stub iface just for the primary IP address (see
* ospf_iface_stubby()) and we expect OS to use primary IP address
* as a source address for both unicast and multicast packets.
*
* FIXME: the primary IP address is currently just the
* lexicographically smallest address on an interface, it should be
* signalized by sysdep code which one is really the primary.
*/
sk->saddr = ifa->addr->ip;
if (sk_setup_multicast(sk) < 0)
goto err;
ifa->sk = sk;
ifa->sk_spf = 0;
ifa->sk_dr = 0;
return 1;
err:
rfree(sk);
return 0;
}
static inline void
ospf_sk_join_spf(struct ospf_iface *ifa)
{
if (ifa->sk_spf)
return;
sk_join_group(ifa->sk, AllSPFRouters);
ifa->sk_spf = 1;
}
static inline void
ospf_sk_join_dr(struct ospf_iface *ifa)
{
if (ifa->sk_dr)
return;
sk_join_group(ifa->sk, AllDRouters);
ifa->sk_dr = 1;
}
static inline void
ospf_sk_leave_spf(struct ospf_iface *ifa)
{
if (!ifa->sk_spf)
return;
sk_leave_group(ifa->sk, AllSPFRouters);
ifa->sk_spf = 0;
}
static inline void
ospf_sk_leave_dr(struct ospf_iface *ifa)
{
if (!ifa->sk_dr)
return;
sk_leave_group(ifa->sk, AllDRouters);
ifa->sk_dr = 0;
}
static inline void
ospf_sk_close(struct ospf_iface *ifa)
{
ASSERT(ifa->sk);
rfree(ifa->sk);
ifa->sk = NULL;
}
/**
* ospf_iface_chstate - handle changes of interface state
* @ifa: OSPF interface
* @state: new state
*
* Many actions must be taken according to interface state changes. New network
* LSAs must be originated, flushed, new multicast sockets to listen for messages for
* %ALLDROUTERS have to be opened, etc.
*/
void
ospf_iface_chstate(struct ospf_iface *ifa, u8 state)
{
struct proto_ospf *po = ifa->oa->po;
struct proto *p = &po->proto;
u8 oldstate = ifa->state;
if (oldstate != state)
{
ifa->state = state;
if (ifa->type == OSPF_IT_VLINK)
{
OSPF_TRACE(D_EVENTS,
"Changing state of virtual link %R from \"%s\" into \"%s\".",
ifa->vid, ospf_is[oldstate], ospf_is[state]);
}
else
{
OSPF_TRACE(D_EVENTS,
"Changing state of iface: %s from \"%s\" into \"%s\".",
ifa->iface->name, ospf_is[oldstate], ospf_is[state]);
if (ifa->iface->flags & IF_MULTICAST)
{
if ((ifa->type != OSPF_IT_NBMA) && (ifa->ioprob == OSPF_I_OK) &&
((state == OSPF_IS_BACKUP) || (state == OSPF_IS_DR)))
ospf_sk_join_dr(ifa);
else
ospf_sk_leave_dr(ifa);
if ((oldstate == OSPF_IS_DR) && (ifa->net_lsa != NULL))
{
ifa->net_lsa->lsa.age = LSA_MAXAGE;
if (state >= OSPF_IS_WAITING)
{
ospf_lsupd_flush_nlsa(po, ifa->net_lsa);
}
if (can_flush_lsa(po))
flush_lsa(ifa->net_lsa, po);
ifa->net_lsa = NULL;
}
}
// FIXME flushling of link LSA
}
}
}
static void
ospf_iface_down(struct ospf_iface *ifa)
{
struct ospf_neighbor *n, *nx;
struct proto_ospf *po = ifa->oa->po;
struct proto *p = &po->proto;
struct ospf_iface *iff;
if (ifa->type != OSPF_IT_VLINK)
{
OSPF_TRACE(D_EVENTS, "Removing interface %s", ifa->iface->name);
/* First of all kill all the related vlinks */
WALK_LIST(iff, po->iface_list)
{
if ((iff->type == OSPF_IT_VLINK) && (iff->vifa == ifa))
ospf_iface_sm(iff, ISM_DOWN);
}
}
WALK_LIST_DELSAFE(n, nx, ifa->neigh_list)
{
OSPF_TRACE(D_EVENTS, "Removing neighbor %I", n->ip);
ospf_neigh_remove(n);
}
if (ifa->type == OSPF_IT_VLINK)
{
ifa->vifa = NULL;
ifa->iface = NULL;
ifa->addr = NULL;
ifa->sk = NULL;
ifa->cost = 0;
ifa->vip = IPA_NONE;
return;
}
else
{
ospf_sk_close(ifa);
rfree(ifa->wait_timer);
rfree(ifa->hello_timer);
rfree(ifa->poll_timer);
rfree(ifa->lock);
rem_node(NODE ifa);
mb_free(ifa);
}
}
/**
* ospf_iface_sm - OSPF interface state machine
* @ifa: OSPF interface
* @event: event comming to state machine
*
* This fully respects 9.3 of RFC 2328 except we don't use %LOOP state of
* interface.
*/
void
ospf_iface_sm(struct ospf_iface *ifa, int event)
{
struct ospf_area *oa = ifa->oa;
DBG("SM on %s %s. Event is '%s'\n", (ifa->type == OSPF_IT_VLINK) ? "vlink" : "iface",
ifa->iface ? ifa->iface->name : "(none)" , ospf_ism[event]);
switch (event)
{
case ISM_UP:
if (ifa->state == OSPF_IS_DOWN)
{
/* Now, nothing should be adjacent */
if ((ifa->type == OSPF_IT_PTP) || (ifa->type == OSPF_IT_VLINK))
{
ospf_iface_chstate(ifa, OSPF_IS_PTP);
}
else
{
if (ifa->priority == 0)
ospf_iface_chstate(ifa, OSPF_IS_DROTHER);
else
{
ospf_iface_chstate(ifa, OSPF_IS_WAITING);
tm_start(ifa->wait_timer, ifa->waitint);
}
}
tm_start(ifa->hello_timer, ifa->helloint);
if (ifa->poll_timer)
tm_start(ifa->poll_timer, ifa->pollint);
hello_timer_hook(ifa->hello_timer);
}
schedule_link_lsa(ifa);
schedule_rt_lsa(ifa->oa);
break;
case ISM_BACKS:
case ISM_WAITF:
if (ifa->state == OSPF_IS_WAITING)
{
bdr_election(ifa);
}
break;
case ISM_NEICH:
if ((ifa->state == OSPF_IS_DROTHER) || (ifa->state == OSPF_IS_DR) ||
(ifa->state == OSPF_IS_BACKUP))
{
bdr_election(ifa);
schedule_rt_lsa(ifa->oa);
}
break;
case ISM_DOWN:
ospf_iface_chstate(ifa, OSPF_IS_DOWN);
ospf_iface_down(ifa);
schedule_rt_lsa(oa);
break;
/*
case ISM_LOOP:
ospf_iface_chstate(ifa, OSPF_IS_LOOP);
break;
case ISM_UNLOOP:
ospf_iface_chstate(ifa, OSPF_IS_DOWN);
break;
*/
default:
bug("OSPF_I_SM - Unknown event?");
break;
}
}
u8
ospf_iface_clasify(struct iface *ifa, struct ifa *addr)
{
if (ipa_nonzero(addr->opposite))
return OSPF_IT_PTP;
if ((ifa->flags & (IF_MULTIACCESS | IF_MULTICAST)) ==
(IF_MULTIACCESS | IF_MULTICAST))
return OSPF_IT_BCAST;
if ((ifa->flags & (IF_MULTIACCESS | IF_MULTICAST)) == IF_MULTIACCESS)
return OSPF_IT_NBMA;
return OSPF_IT_PTP;
}
struct ospf_iface *
ospf_iface_find(struct proto_ospf *p, struct iface *what)
{
struct ospf_iface *i;
WALK_LIST(i, p->iface_list) if ((i->iface == what) && (i->type != OSPF_IT_VLINK))
return i;
return NULL;
}
static void
ospf_iface_add(struct object_lock *lock)
{
struct ospf_iface *ifa = lock->data;
struct proto_ospf *po = ifa->oa->po;
struct proto *p = &po->proto;
ifa->lock = lock;
if (ospf_sk_open(ifa))
{
if (ifa->type != OSPF_IT_NBMA)
ospf_sk_join_spf(ifa);
}
else
{
log(L_ERR "%s: Socket open failed on interface %s, declaring as stub", p->name, ifa->iface->name);
ifa->ioprob = OSPF_I_SK;
ifa->stub = 1;
}
ifa->state = OSPF_IS_DOWN;
ospf_iface_sm(ifa, ISM_UP);
}
void
ospf_iface_new(struct proto_ospf *po, struct iface *iface, struct ifa *addr,
struct ospf_area_config *ac, struct ospf_iface_patt *ip)
{
struct proto *p = &po->proto;
struct ospf_iface *ifa;
struct nbma_node *nbma, *nb;
struct object_lock *lock;
struct ospf_area *oa;
if (ip->type != OSPF_IT_VLINK)
OSPF_TRACE(D_EVENTS, "Adding interface %s", iface->name);
ifa = mb_allocz(p->pool, sizeof(struct ospf_iface));
ifa->iface = iface;
ifa->addr = addr;
ifa->cost = ip->cost;
ifa->rxmtint = ip->rxmtint;
ifa->inftransdelay = ip->inftransdelay;
ifa->priority = ip->priority;
ifa->helloint = ip->helloint;
ifa->pollint = ip->pollint;
ifa->strictnbma = ip->strictnbma;
ifa->waitint = ip->waitint;
ifa->dead = (ip->dead == 0) ? ip->deadc * ifa->helloint : ip->dead;
ifa->stub = ospf_iface_stubby(ip, addr);
ifa->ioprob = OSPF_I_OK;
ifa->rxbuf = ip->rxbuf;
#ifdef OSPFv2
ifa->autype = ip->autype;
ifa->passwords = ip->passwords;
#endif
#ifdef OSPFv3
ifa->instance_id = ip->instance_id;
#endif
if (ip->type == OSPF_IT_UNDEF)
ifa->type = ospf_iface_clasify(iface, addr);
else
ifa->type = ip->type;
/* a loopback/dummy address */
if ((addr->pxlen == MAX_PREFIX_LENGTH) && ipa_zero(addr->opposite))
ifa->stub = 1;
#ifdef OSPFv2
if ((ifa->type != OSPF_IT_PTP) && (ifa->type != OSPF_IT_VLINK) &&
(addr->flags & IA_UNNUMBERED))
{
log(L_WARN "%s: Missing proper IP prefix on interface %s, forcing point-to-point mode",
p->name, iface->name);
ifa->type = OSPF_IT_PTP;
}
#endif
init_list(&ifa->neigh_list);
init_list(&ifa->nbma_list);
WALK_LIST(nb, ip->nbma_list)
{
nbma = mb_alloc(p->pool, sizeof(struct nbma_node));
nbma->ip = nb->ip;
nbma->eligible = nb->eligible;
add_tail(&ifa->nbma_list, NODE nbma);
}
/* Add hello timer */
ifa->hello_timer = tm_new(p->pool);
ifa->hello_timer->data = ifa;
ifa->hello_timer->randomize = 0;
ifa->hello_timer->hook = hello_timer_hook;
ifa->hello_timer->recurrent = ifa->helloint;
DBG("%s: Installing hello timer. (%u)\n", p->name, ifa->helloint);
if (ifa->type == OSPF_IT_NBMA)
{
ifa->poll_timer = tm_new(p->pool);
ifa->poll_timer->data = ifa;
ifa->poll_timer->randomize = 0;
ifa->poll_timer->hook = poll_timer_hook;
ifa->poll_timer->recurrent = ifa->pollint;
DBG("%s: Installing poll timer. (%u)\n", p->name, ifa->pollint);
}
else
ifa->poll_timer = NULL;
ifa->wait_timer = tm_new(p->pool);
ifa->wait_timer->data = ifa;
ifa->wait_timer->randomize = 0;
ifa->wait_timer->hook = wait_timer_hook;
ifa->wait_timer->recurrent = 0;
DBG("%s: Installing wait timer. (%u)\n", p->name, ifa->waitint);
add_tail(&((struct proto_ospf *) p)->iface_list, NODE ifa);
ifa->state = OSPF_IS_DOWN;
ifa->oa = NULL;
WALK_LIST(oa, po->area_list)
{
if (oa->areaid == ac->areaid)
{
ifa->oa = oa;
break;
}
}
if (!ifa->oa)
bug("Cannot add any area to accepted Interface");
else
if (ifa->type == OSPF_IT_VLINK)
{
ifa->oa = po->backbone;
ifa->voa = oa;
ifa->vid = ip->vid;
return; /* Don't lock, don't add sockets */
}
/*
* In some cases we allow more ospf_ifaces on one physical iface.
* In OSPFv2, if they use different IP address prefix.
* In OSPFv3, if they use different instance_id.
* Therefore, we store such info to lock->addr field.
*/
lock = olock_new(p->pool);
#ifdef OSPFv2
lock->addr = ifa->addr->prefix;
#else /* OSPFv3 */
lock->addr = _MI(0,0,0,ifa->instance_id);
#endif
lock->type = OBJLOCK_IP;
lock->port = OSPF_PROTO;
lock->iface = iface;
lock->data = ifa;
lock->hook = ospf_iface_add;
olock_acquire(lock);
}
#ifdef OSPFv2
void
ospf_ifa_notify(struct proto *p, unsigned flags, struct ifa *a)
{
struct proto_ospf *po = (struct proto_ospf *) p;
struct ospf_config *cf = (struct ospf_config *) (p->cf);
if (a->flags & IA_SECONDARY)
return;
if (a->scope <= SCOPE_LINK)
return;
/* In OSPFv2, we create OSPF iface for each address. */
if (flags & IF_CHANGE_UP)
{
int done = 0;
struct ospf_area_config *ac;
WALK_LIST(ac, cf->area_list)
{
struct ospf_iface_patt *ip = (struct ospf_iface_patt *)
iface_patt_find(&ac->patt_list, a->iface, a);
if (ip)
{
if (!done)
ospf_iface_new(po, a->iface, a, ac, ip);
done++;
}
}
if (done > 1)
log(L_WARN "%s: Interface %s (IP %I) matches for multiple areas", p->name, a->iface->name, a->ip);
}
if (flags & IF_CHANGE_DOWN)
{
struct ospf_iface *ifa, *ifx;
WALK_LIST_DELSAFE(ifa, ifx, po->iface_list)
{
if ((ifa->type != OSPF_IT_VLINK) && (ifa->addr == a))
ospf_iface_sm(ifa, ISM_DOWN);
/* See a note in ospf_iface_notify() */
}
}
}
#else /* OSPFv3 */
static inline int iflag_test(u32 *a, u8 i)
{
return a[i / 32] & (1u << (i % 32));
}
static inline void iflag_set(u32 *a, u8 i)
{
a[i / 32] |= (1u << (i % 32));
}
void
ospf_ifa_notify(struct proto *p, unsigned flags, struct ifa *a)
{
struct proto_ospf *po = (struct proto_ospf *) p;
struct ospf_config *cf = (struct ospf_config *) (p->cf);
if (a->flags & IA_SECONDARY)
return;
if (a->scope < SCOPE_LINK)
return;
/* In OSPFv3, we create OSPF iface for link-local address,
other addresses are used for link-LSA. */
if (a->scope == SCOPE_LINK)
{
if (flags & IF_CHANGE_UP)
{
u32 found_all[8] = {};
struct ospf_area_config *ac;
WALK_LIST(ac, cf->area_list)
{
u32 found_new[8] = {};
struct iface_patt *pt;
WALK_LIST(pt, ac->patt_list)
{
if (iface_patt_match(pt, a->iface, a))
{
struct ospf_iface_patt *ipt = (struct ospf_iface_patt *) pt;
/* If true, we already assigned that IID and we skip
this to implement first-match behavior */
if (iflag_test(found_new, ipt->instance_id))
continue;
/* If true, we already assigned that in a different area,
we log collision */
if (iflag_test(found_all, ipt->instance_id))
{
log(L_WARN "%s: Interface %s (IID %d) matches for multiple areas",
p->name, a->iface->name, ipt->instance_id);
continue;
}
iflag_set(found_all, ipt->instance_id);
iflag_set(found_new, ipt->instance_id);
ospf_iface_new(po, a->iface, a, ac, ipt);
}
}
}
}
if (flags & IF_CHANGE_DOWN)
{
struct ospf_iface *ifa, *ifx;
WALK_LIST_DELSAFE(ifa, ifx, po->iface_list)
{
if ((ifa->type != OSPF_IT_VLINK) && (ifa->addr == a))
ospf_iface_sm(ifa, ISM_DOWN);
/* See a note in ospf_iface_notify() */
}
}
}
else
{
struct ospf_iface *ifa;
WALK_LIST(ifa, po->iface_list)
{
if (ifa->iface == a->iface)
{
schedule_rt_lsa(ifa->oa);
/* Event 5 from RFC5340 4.4.3. */
schedule_link_lsa(ifa);
return;
}
}
}
}
#endif
void
ospf_iface_change_mtu(struct proto_ospf *po, struct ospf_iface *ifa)
{
struct proto *p = &po->proto;
struct ospf_packet *op;
struct ospf_neighbor *n;
OSPF_TRACE(D_EVENTS, "Changing MTU on interface %s.", ifa->iface->name);
if (ifa->sk)
{
ifa->sk->rbsize = rxbufsize(ifa);
ifa->sk->tbsize = ifa->iface->mtu;
sk_reallocate(ifa->sk);
}
WALK_LIST(n, ifa->neigh_list)
{
op = (struct ospf_packet *) n->ldbdes;
n->ldbdes = mb_allocz(n->pool, ifa->iface->mtu);
if (ntohs(op->length) <= ifa->iface->mtu) /* If the packet in old buffer is bigger, let it filled by zeros */
memcpy(n->ldbdes, op, ifa->iface->mtu); /* If the packet is old is same or smaller, copy it */
rfree(op);
}
}
void
ospf_iface_notify(struct proto *p, unsigned flags, struct iface *iface)
{
struct proto_ospf *po = (struct proto_ospf *) p;
DBG("%s: If notify called\n", p->name);
if (iface->flags & IF_IGNORE)
return;
if (flags & IF_CHANGE_DOWN)
{
struct ospf_iface *ifa, *ifx;
WALK_LIST_DELSAFE(ifa, ifx, po->iface_list)
if ((ifa->type != OSPF_IT_VLINK) && (ifa->iface == iface))
ospf_iface_sm(ifa, ISM_DOWN);
/* We use here that even shutting down iface also shuts down
the vlinks, but vlinks are not freed and stays in the
iface_list even when down */
}
if (flags & IF_CHANGE_MTU)
{
struct ospf_iface *ifa;
WALK_LIST(ifa, po->iface_list)
if ((ifa->type != OSPF_IT_VLINK) && (ifa->iface == iface))
ospf_iface_change_mtu(po, ifa);
}
}
void
ospf_iface_info(struct ospf_iface *ifa)
{
char *strict = "(strict)";
if ((ifa->type != OSPF_IT_NBMA) || (ifa->strictnbma == 0))
strict = "";
if (ifa->type == OSPF_IT_VLINK)
{
cli_msg(-1015, "Virtual link to %R:", ifa->vid);
cli_msg(-1015, "\tPeer IP: %I", ifa->vip);
cli_msg(-1015, "\tTransit area: %R (%u)", ifa->voa->areaid,
ifa->voa->areaid);
cli_msg(-1015, "\tInterface: \"%s\"",
(ifa->iface ? ifa->iface->name : "(none)"));
}
else
{
#ifdef OSPFv2
if (ifa->addr->flags & IA_UNNUMBERED)
cli_msg(-1015, "Interface %s (peer %I)", ifa->iface->name, ifa->addr->opposite);
else
cli_msg(-1015, "Interface %s (%I/%d)", ifa->iface->name, ifa->addr->prefix, ifa->addr->pxlen);
#else /* OSPFv3 */
cli_msg(-1015, "Interface %s (IID %d)", ifa->iface->name, ifa->instance_id);
#endif
cli_msg(-1015, "\tType: %s %s", ospf_it[ifa->type], strict);
cli_msg(-1015, "\tArea: %R (%u)", ifa->oa->areaid, ifa->oa->areaid);
}
cli_msg(-1015, "\tState: %s %s", ospf_is[ifa->state],
ifa->stub ? "(stub)" : "");
cli_msg(-1015, "\tPriority: %u", ifa->priority);
cli_msg(-1015, "\tCost: %u", ifa->cost);
cli_msg(-1015, "\tHello timer: %u", ifa->helloint);
if (ifa->type == OSPF_IT_NBMA)
{
cli_msg(-1015, "\tPoll timer: %u", ifa->pollint);
}
cli_msg(-1015, "\tWait timer: %u", ifa->waitint);
cli_msg(-1015, "\tDead timer: %u", ifa->dead);
cli_msg(-1015, "\tRetransmit timer: %u", ifa->rxmtint);
if ((ifa->type == OSPF_IT_BCAST) || (ifa->type == OSPF_IT_NBMA))
{
cli_msg(-1015, "\tDesigned router (ID): %R", ifa->drid);
cli_msg(-1015, "\tDesigned router (IP): %I", ifa->drip);
cli_msg(-1015, "\tBackup designed router (ID): %R", ifa->bdrid);
cli_msg(-1015, "\tBackup designed router (IP): %I", ifa->bdrip);
}
}
void
ospf_iface_shutdown(struct ospf_iface *ifa)
{
init_list(&ifa->neigh_list);
hello_timer_hook(ifa->hello_timer);
}