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bird/nest/iface.c

618 lines
12 KiB
C

/*
* BIRD -- Management of Interfaces and Neighbor Cache
*
* (c) 1998--1999 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"
#include "lib/string.h"
#include "conf/conf.h"
static pool *if_pool;
static void auto_router_id(void);
/*
* Neighbor Cache
*
* FIXME: Use hashing to get some real speed.
*/
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 */
{
struct ifa *b;
if (!(i->flags & IF_UP))
return 0;
if ((i->flags & IF_UNNUMBERED) && ipa_equal(*a, i->addr->opposite))
return 1;
WALK_LIST(b, i->addrs)
if (ipa_in_net(*a, b->prefix, b->pxlen))
{
if (ipa_equal(*a, b->prefix) || /* Network address */
ipa_equal(*a, b->brd) || /* Broadcast */
ipa_equal(*a, b->ip)) /* Our own address */
return -1;
return 1;
}
return 0;
}
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) /* FIXME: Search for _optimal_ iface route? */
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->core_state != FS_FLUSHING)
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, i->name);
n->iface = NULL;
if (n->proto->neigh_notify && n->proto->core_state != FS_FLUSHING)
n->proto->neigh_notify(n);
if (!(n->flags & NEF_STICKY))
{
rem_node(&n->n);
sl_free(neigh_slab, n);
}
}
i->neigh = NULL;
}
void
neigh_prune(void)
{
neighbor *n, *m, **N;
struct iface *i;
DBG("Pruning neighbors\n");
WALK_LIST(i, iface_list)
{
N = &i->neigh;
while (n = *N)
{
if (n->proto->core_state == FS_FLUSHING)
{
*N = n->sibling;
rem_node(&n->n);
sl_free(neigh_slab, n);
continue;
}
N = &n->sibling;
}
}
}
/*
* The Interface List
*/
list iface_list;
void
ifa_dump(struct ifa *a)
{
debug("\t%I, net %I/%-2d bc %I -> %I%s%s\n", a->ip, a->prefix, a->pxlen, a->brd, a->opposite,
(a->flags & IF_UP) ? "" : " DOWN",
(a->flags & IA_PRIMARY) ? "" : " SEC");
}
void
if_dump(struct iface *i)
{
struct ifa *a;
debug("IF%d: %s", i->index, i->name);
if (i->flags & IF_ADMIN_DOWN)
debug(" ADMIN-DOWN");
if (i->flags & IF_UP)
debug(" UP");
else
debug(" DOWN");
if (i->flags & IF_LINK_UP)
debug(" LINK-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");
if (i->flags & IF_TMP_DOWN)
debug(" TDOWN");
debug(" MTU=%d\n", i->mtu);
WALK_LIST(a, i->addrs)
{
ifa_dump(a);
ASSERT((a != i->addr) == !(a->flags & IA_PRIMARY));
}
}
void
if_dump_all(void)
{
struct iface *i;
debug("Known network interfaces:\n");
WALK_LIST(i, iface_list)
if_dump(i);
debug("Router ID: %08x\n", config->router_id);
}
static inline unsigned
if_what_changed(struct iface *i, struct iface *j)
{
unsigned c;
if (((i->flags ^ j->flags) & ~(IF_UP | IF_ADMIN_DOWN | IF_UPDATED | IF_LINK_UP | IF_TMP_DOWN | IF_JUST_CREATED))
|| i->index != j->index)
return IF_CHANGE_TOO_MUCH;
c = 0;
if ((i->flags ^ j->flags) & IF_UP)
c |= (i->flags & IF_UP) ? IF_CHANGE_DOWN : IF_CHANGE_UP;
if (i->mtu != j->mtu)
c |= IF_CHANGE_MTU;
return c;
}
static inline void
if_copy(struct iface *to, struct iface *from)
{
to->flags = from->flags | (to->flags & IF_TMP_DOWN);
to->mtu = from->mtu;
}
static void
ifa_notify_change(unsigned c, struct ifa *a)
{
struct proto *p;
debug("IFA change notification (%x) for %s:%I\n", c, a->iface->name, a->ip);
WALK_LIST(p, proto_list)
if (p->ifa_notify)
p->ifa_notify(p, c, a);
}
static void
if_notify_change(unsigned c, struct iface *i)
{
struct proto *p;
struct ifa *a;
if (i->flags & IF_JUST_CREATED)
{
i->flags &= ~IF_JUST_CREATED;
c |= IF_CHANGE_CREATE | IF_CHANGE_MTU;
}
debug("Interface change notification (%x) for %s\n", c, i->name);
if_dump(i);
if (c & IF_CHANGE_UP)
neigh_if_up(i);
if (c & IF_CHANGE_DOWN)
WALK_LIST(a, i->addrs)
{
a->flags = (i->flags & ~IA_FLAGS) | (a->flags & IA_FLAGS);
ifa_notify_change(IF_CHANGE_DOWN, a);
}
WALK_LIST(p, proto_list)
if (p->if_notify)
p->if_notify(p, c, i);
if (c & IF_CHANGE_UP)
WALK_LIST(a, i->addrs)
{
a->flags = (i->flags & ~IA_FLAGS) | (a->flags & IA_FLAGS);
ifa_notify_change(IF_CHANGE_UP, a);
}
if (c & IF_CHANGE_DOWN)
neigh_if_down(i);
}
static unsigned
if_recalc_flags(struct iface *i, unsigned flags)
{
if ((flags & (IF_ADMIN_DOWN | IF_TMP_DOWN)) ||
!(flags & IF_LINK_UP) ||
!i->addr)
flags &= ~IF_UP;
else
flags |= IF_UP;
return flags;
}
static void
if_change_flags(struct iface *i, unsigned flags)
{
unsigned of = i->flags;
i->flags = if_recalc_flags(i, flags);
if ((i->flags ^ of) & IF_UP)
if_notify_change((i->flags & IF_UP) ? IF_CHANGE_UP : IF_CHANGE_DOWN, i);
}
struct iface *
if_update(struct iface *new)
{
struct iface *i;
struct ifa *a, *b;
unsigned c;
WALK_LIST(i, iface_list)
if (!strcmp(new->name, i->name))
{
new->addr = i->addr;
new->flags = if_recalc_flags(new, new->flags);
c = if_what_changed(i, new);
if (c & IF_CHANGE_TOO_MUCH) /* Changed a lot, convert it to down/up */
{
DBG("Interface %s changed too much -- forcing down/up transition\n", i->name);
if_change_flags(i, i->flags | IF_TMP_DOWN);
rem_node(&i->n);
new->addr = i->addr;
memcpy(&new->addrs, &i->addrs, sizeof(i->addrs));
memcpy(i, new, sizeof(*i));
goto newif;
}
else if (c)
{
if_copy(i, new);
if_notify_change(c, i);
}
i->flags |= IF_UPDATED;
return i;
}
i = mb_alloc(if_pool, sizeof(struct iface));
memcpy(i, new, sizeof(*i));
init_list(&i->addrs);
newif:
i->flags |= IF_UPDATED | IF_TMP_DOWN; /* Tmp down as we don't have addresses yet */
add_tail(&iface_list, &i->n);
return i;
}
void
if_start_update(void)
{
struct iface *i;
struct ifa *a;
WALK_LIST(i, iface_list)
{
i->flags &= ~IF_UPDATED;
WALK_LIST(a, i->addrs)
a->flags &= ~IF_UPDATED;
}
}
void
if_end_partial_update(struct iface *i)
{
if (i->flags & IF_TMP_DOWN)
if_change_flags(i, i->flags & ~IF_TMP_DOWN);
}
void
if_end_update(void)
{
struct iface *i, j;
struct ifa *a, *b;
if (!config->router_id)
auto_router_id();
WALK_LIST(i, iface_list)
{
if (!(i->flags & IF_UPDATED))
if_change_flags(i, (i->flags & ~IF_LINK_UP) | IF_ADMIN_DOWN);
else
{
WALK_LIST_DELSAFE(a, b, i->addrs)
if (!(a->flags & IF_UPDATED))
ifa_delete(a);
if_end_partial_update(i);
}
}
}
void
if_feed_baby(struct proto *p)
{
struct iface *i;
struct ifa *a;
if (!p->if_notify && !p->ifa_notify)
return;
debug("Announcing interfaces to new protocol %s\n", p->name);
WALK_LIST(i, iface_list)
{
if (p->if_notify)
p->if_notify(p, IF_CHANGE_CREATE | ((i->flags & IF_UP) ? IF_CHANGE_UP : 0), i);
if (p->ifa_notify && (i->flags & IF_UP))
WALK_LIST(a, i->addrs)
p->ifa_notify(p, IF_CHANGE_CREATE | IF_CHANGE_UP, a);
}
}
struct iface *
if_find_by_index(unsigned idx)
{
struct iface *i;
WALK_LIST(i, iface_list)
if (i->index == idx)
return i;
return NULL;
}
struct iface *
if_find_by_name(char *name)
{
struct iface *i;
WALK_LIST(i, iface_list)
if (!strcmp(i->name, name))
return i;
return NULL;
}
static int
ifa_recalc_primary(struct iface *i)
{
struct ifa *a, *b = NULL;
int res;
WALK_LIST(a, i->addrs)
{
if (!(a->flags & IA_SECONDARY) && (!b || a->scope > b->scope))
b = a;
a->flags &= ~IA_PRIMARY;
}
res = (b != i->addr);
i->addr = b;
if (b)
{
b->flags |= IA_PRIMARY;
rem_node(&b->n);
add_head(&i->addrs, &b->n);
}
return res;
}
struct ifa *
ifa_update(struct ifa *a)
{
struct iface *i = a->iface;
struct ifa *b;
WALK_LIST(b, i->addrs)
if (ipa_equal(b->ip, a->ip))
{
if (ipa_equal(b->prefix, a->prefix) &&
b->pxlen == a->pxlen &&
ipa_equal(b->brd, a->brd) &&
ipa_equal(b->opposite, a->opposite) &&
b->scope == a->scope)
{
b->flags |= IF_UPDATED;
return b;
}
ifa_delete(b);
break;
}
b = mb_alloc(if_pool, sizeof(struct ifa));
memcpy(b, a, sizeof(struct ifa));
add_tail(&i->addrs, &b->n);
b->flags = (i->flags & ~IA_FLAGS) | (a->flags & IA_FLAGS);
if ((!i->addr || i->addr->scope < b->scope) && ifa_recalc_primary(i))
if_change_flags(i, i->flags | IF_TMP_DOWN);
if (b->flags & IF_UP)
ifa_notify_change(IF_CHANGE_CREATE | IF_CHANGE_UP, b);
return b;
}
void
ifa_delete(struct ifa *a)
{
struct iface *i = a->iface;
struct ifa *b;
WALK_LIST(b, i->addrs)
if (ipa_equal(b->ip, a->ip))
{
rem_node(&b->n);
if (b->flags & IF_UP)
{
b->flags &= ~IF_UP;
ifa_notify_change(IF_CHANGE_DOWN, b);
}
if (b->flags & IA_PRIMARY)
{
if_change_flags(i, i->flags | IF_TMP_DOWN);
ifa_recalc_primary(i);
}
mb_free(b);
return;
}
}
static void
auto_router_id(void) /* FIXME: What if we run IPv6??? */
{
struct iface *i, *j;
j = NULL;
WALK_LIST(i, iface_list)
if ((i->flags & IF_LINK_UP) &&
!(i->flags & (IF_UNNUMBERED | IF_IGNORE | IF_ADMIN_DOWN)) &&
i->addr &&
(!j || ipa_to_u32(i->addr->ip) < ipa_to_u32(j->addr->ip)))
j = i;
if (!j)
die("Cannot determine router ID (no suitable network interface found), please configure it manually");
debug("Guessed router ID %I (%s)\n", j->addr->ip, j->name);
config->router_id = ipa_to_u32(j->addr->ip);
}
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);
}
/*
* Interface Pattern Lists
*/
struct iface_patt *
iface_patt_match(list *l, struct iface *i)
{
struct iface_patt *p;
WALK_LIST(p, *l)
{
char *t = p->pattern;
int ok = 1;
if (*t == '-')
{
t++;
ok = 0;
}
if (patmatch(t, i->name))
return ok ? p : NULL;
}
return NULL;
}
int
iface_patts_equal(list *a, list *b, int (*comp)(struct iface_patt *, struct iface_patt *))
{
struct iface_patt *x, *y;
x = HEAD(*a);
y = HEAD(*b);
while (x->n.next && y->n.next)
{
if (strcmp(x->pattern, y->pattern) || comp && !comp(x, y))
return 0;
x = (void *) x->n.next;
y = (void *) y->n.next;
}
return (!x->n.next && !y->n.next);
}