bird/nest/iface.c

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/*
* BIRD -- Management of Interfaces and Neighbor Cache
*
* (c) 1998 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#define LOCAL_DEBUG
#include "nest/bird.h"
#include "nest/iface.h"
#include "nest/protocol.h"
#include "lib/resource.h"
static pool *if_pool;
u32 router_id;
/*
* Neighbor Cache
*
* FIXME: Use hashing to get some real speed.
* FIXME: Cleanup when a protocol goes down.
*/
static slab *neigh_slab;
static list neigh_list;
static int
if_connected(ip_addr *a, struct iface *i) /* -1=error, 1=match, 0=no match */
{
if (i->flags & (IF_ADMIN_DOWN | IF_IGNORE))
return 0;
if ((i->flags & IF_UNNUMBERED) && ipa_equal(*a, i->opposite))
return 1;
if (!ipa_in_net(*a, i->prefix, i->pxlen))
return 0;
if (ipa_equal(*a, i->prefix) || /* Network address */
ipa_equal(*a, i->brd) || /* Broadcast */
ipa_equal(*a, i->ip)) /* Our own address */
return -1;
if (!(i->flags & IF_UP))
return 0;
return 1;
}
neighbor *
neigh_find(struct proto *p, ip_addr *a, unsigned flags)
{
neighbor *n;
int class;
struct iface *i, *j;
WALK_LIST(n, neigh_list)
if (n->proto == p && ipa_equal(*a, n->addr))
return n;
class = ipa_classify(*a);
if (class < 0) /* Invalid address */
return NULL;
if ((class & IADDR_SCOPE_MASK) < SCOPE_SITE ||
!(class & IADDR_HOST))
return NULL; /* Bad scope or a somecast */
j = NULL;
WALK_LIST(i, iface_list)
switch (if_connected(a, i))
{
case -1:
return NULL;
case 1:
if (!j || j->pxlen > i->pxlen)
j = i;
/* Fall-thru */
}
if (!j && !(flags & NEF_STICKY))
return NULL;
n = sl_alloc(neigh_slab);
n->addr = *a;
n->iface = j;
add_tail(&neigh_list, &n->n);
if (j)
{
n->sibling = j->neigh;
j->neigh = n;
}
else
n->sibling = NULL;
n->proto = p;
n->data = NULL;
n->flags = flags;
return n;
}
void
neigh_dump(neighbor *n)
{
debug("%p %I ", n, n->addr);
if (n->iface)
debug("%s ", n->iface->name);
else
debug("[] ");
debug("%s %p", n->proto->name, n->data);
if (n->flags & NEF_STICKY)
debug("STICKY");
debug("\n");
}
void
neigh_dump_all(void)
{
neighbor *n;
debug("Known neighbors:\n");
WALK_LIST(n, neigh_list)
neigh_dump(n);
debug("\n");
}
static void
neigh_if_up(struct iface *i)
{
neighbor *n;
WALK_LIST(n, neigh_list)
if (!n->iface &&
if_connected(&n->addr, i) > 0)
{
n->iface = i;
n->sibling = i->neigh;
i->neigh = n;
DBG("Waking up sticky neighbor %I\n", n->addr);
if (n->proto->neigh_notify)
n->proto->neigh_notify(n);
}
}
static void
neigh_if_down(struct iface *i)
{
neighbor *n, *m;
for(m=i->neigh; n = m;)
{
m = n->sibling;
DBG("Flushing neighbor %I on %s\n", n->addr, n->iface->name);
n->iface = NULL;
if (n->proto->neigh_notify)
n->proto->neigh_notify(n);
if (!(n->flags & NEF_STICKY))
{
rem_node(&n->n);
sl_free(neigh_slab, n);
}
i->neigh = NULL;
}
}
/*
* The Interface List
*/
list iface_list;
void
if_dump(struct iface *i)
{
debug("IF%d: %s", i->index, i->name);
if (i->flags & IF_ADMIN_DOWN)
debug(" ADMIN-DOWN");
if (i->flags & IF_UP)
debug(" UP");
if (i->flags & IF_MULTIACCESS)
debug(" MA");
if (i->flags & IF_UNNUMBERED)
debug(" UNNUM");
if (i->flags & IF_BROADCAST)
debug(" BC");
if (i->flags & IF_MULTICAST)
debug(" MC");
if (i->flags & IF_TUNNEL)
debug(" TUNL");
if (i->flags & IF_LOOPBACK)
debug(" LOOP");
if (i->flags & IF_IGNORE)
debug(" IGN");
debug(" MTU=%d\n", i->mtu);
debug("\t%I, net %I/%-2d bc %I -> %I\n", i->ip, i->prefix, i->pxlen, i->brd, i->opposite);
}
void
if_dump_all(void)
{
struct iface *i;
debug("Known network interfaces:\n");
WALK_LIST(i, iface_list)
if_dump(i);
debug("\nRouter ID: %08x\n\n", router_id);
}
static inline int
if_change_too_big_p(struct iface *i, struct iface *j)
{
if (!ipa_equal(i->ip, j->ip) ||
!ipa_equal(i->prefix, j->prefix) ||
i->pxlen != j->pxlen ||
!ipa_equal(i->brd, j->brd) ||
!ipa_equal(i->opposite, j->opposite))
return 1; /* Changed addresses */
if ((i->flags ^ j->flags) & ~(IF_UP | IF_ADMIN_DOWN | IF_UPDATED))
return 1;
return 0;
}
static inline void
if_copy(struct iface *to, struct iface *from)
{
to->flags = from->flags;
to->mtu = from->mtu;
to->index = from->index;
}
static unsigned
if_changed(struct iface *i, struct iface *j)
{
unsigned f = 0;
if (i->mtu != j->mtu)
f |= IF_CHANGE_MTU;
if ((i->flags ^ j->flags) & ~IF_UPDATED)
{
f |= IF_CHANGE_FLAGS;
if ((i->flags ^ j->flags) & IF_UP)
if (i->flags & IF_UP)
f |= IF_CHANGE_DOWN;
else
f |= IF_CHANGE_UP;
}
return f;
}
static void
if_notify_change(unsigned c, struct iface *old, struct iface *new)
{
struct proto *p;
debug("Interface change notification (%x) for %s\n", c, new->name);
if (old)
if_dump(old);
if (new)
if_dump(new);
if (c & IF_CHANGE_UP)
neigh_if_up(new);
WALK_LIST(p, proto_list)
if (p->if_notify)
p->if_notify(p, c, old, new);
if (c & IF_CHANGE_DOWN)
neigh_if_down(old);
}
void
if_update(struct iface *new)
{
struct iface *i;
unsigned c;
WALK_LIST(i, iface_list)
if (!strcmp(new->name, i->name))
{
if (if_change_too_big_p(i, new)) /* Changed a lot, convert it to down/up */
{
DBG("Interface %s changed too much -- forcing down/up transition\n", i->name);
i->flags &= ~IF_UP;
if_notify_change(IF_CHANGE_DOWN | IF_CHANGE_FLAGS, i, NULL);
rem_node(&i->n);
goto newif;
}
c = if_changed(i, new);
if_copy(i, new); /* Even if c==0 as we might need to update i->index et al. */
i->flags |= IF_UPDATED;
if (c)
if_notify_change(c, i, new);
return;
}
i = mb_alloc(if_pool, sizeof(struct iface));
newif:
memcpy(i, new, sizeof(*i));
i->flags |= IF_UPDATED;
add_tail(&iface_list, &i->n);
if_notify_change(IF_CHANGE_CREATE | ((i->flags & IF_UP) ? IF_CHANGE_UP : 0)
| IF_CHANGE_FLAGS | IF_CHANGE_MTU, NULL, i);
}
void
if_end_update(void)
{
struct iface *i, j;
WALK_LIST(i, iface_list)
if (i->flags & IF_UPDATED)
i->flags &= ~IF_UPDATED;
else
{
memcpy(&j, i, sizeof(struct iface));
i->flags = (i->flags & ~IF_UP) | IF_ADMIN_DOWN;
if_notify_change(IF_CHANGE_DOWN | IF_CHANGE_FLAGS, &j, i);
}
}
void
if_feed_baby(struct proto *p)
{
struct iface *i;
if (!p->if_notify)
return;
debug("Announcing interfaces to new protocol %s\n", p->name);
WALK_LIST(i, iface_list)
p->if_notify(p, IF_CHANGE_CREATE | ((i->flags & IF_UP) ? IF_CHANGE_UP : 0), NULL, i);
}
void
auto_router_id(void) /* FIXME: What if we run IPv6??? */
{
struct iface *i, *j;
if (router_id)
return;
j = NULL;
WALK_LIST(i, iface_list)
if ((i->flags & IF_UP) &&
!(i->flags & (IF_UNNUMBERED | IF_LOOPBACK | IF_IGNORE)) &&
(!j || ipa_to_u32(i->ip) < ipa_to_u32(j->ip)))
j = i;
if (!j) /* FIXME: allow configuration or running without RID */
die("Cannot determine router ID, please configure manually");
router_id = ipa_to_u32(j->ip);
debug("Router ID set to %08x (%s)\n", router_id, j->name);
}
void
if_init(void)
{
if_pool = rp_new(&root_pool, "Interfaces");
init_list(&iface_list);
neigh_slab = sl_new(if_pool, sizeof(neighbor));
init_list(&neigh_list);
}