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bird/nest/rt-table.c
Ondrej Zajicek c07c65d6d0 Escaped debbuging message removed.
2009-06-01 23:18:45 +02:00

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/*
* BIRD -- Routing Tables
*
* (c) 1998--2000 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
/**
* DOC: Routing tables
*
* Routing tables are probably the most important structures BIRD uses. They
* hold all the information about known networks, the associated routes and
* their attributes.
*
* There are multiple routing tables (a primary one together with any
* number of secondary ones if requested by the configuration). Each table
* is basically a FIB containing entries describing the individual
* destination networks. For each network (represented by structure &net),
* there is a one-way linked list of route entries (&rte), the first entry
* on the list being the best one (i.e., the one we currently use
* for routing), the order of the other ones is undetermined.
*
* The &rte contains information specific to the route (preference, protocol
* metrics, time of last modification etc.) and a pointer to a &rta structure
* (see the route attribute module for a precise explanation) holding the
* remaining route attributes which are expected to be shared by multiple
* routes in order to conserve memory.
*/
#undef LOCAL_DEBUG
#include "nest/bird.h"
#include "nest/route.h"
#include "nest/protocol.h"
#include "nest/cli.h"
#include "nest/iface.h"
#include "lib/resource.h"
#include "lib/event.h"
#include "lib/string.h"
#include "conf/conf.h"
#include "filter/filter.h"
#include "lib/string.h"
#include "lib/alloca.h"
static slab *rte_slab;
static linpool *rte_update_pool;
static pool *rt_table_pool;
static list routing_tables;
static void rt_format_via(rte *e, byte *via);
static void
rte_init(struct fib_node *N)
{
net *n = (net *) N;
N->flags = 0;
n->routes = NULL;
}
/**
* rte_find - find a route
* @net: network node
* @p: protocol
*
* The rte_find() function returns a route for destination @net
* which belongs has been defined by protocol @p.
*/
rte *
rte_find(net *net, struct proto *p)
{
rte *e = net->routes;
while (e && e->attrs->proto != p)
e = e->next;
return e;
}
/**
* rte_get_temp - get a temporary &rte
* @a: attributes to assign to the new route (a &rta; in case it's
* un-cached, rte_update() will create a cached copy automatically)
*
* Create a temporary &rte and bind it with the attributes @a.
* Also set route preference to the default preference set for
* the protocol.
*/
rte *
rte_get_temp(rta *a)
{
rte *e = sl_alloc(rte_slab);
e->attrs = a;
e->flags = 0;
e->pref = a->proto->preference;
return e;
}
rte *
rte_do_cow(rte *r)
{
rte *e = sl_alloc(rte_slab);
memcpy(e, r, sizeof(rte));
e->attrs = rta_clone(r->attrs);
e->flags = 0;
return e;
}
static int /* Actually better or at least as good as */
rte_better(rte *new, rte *old)
{
int (*better)(rte *, rte *);
if (!old)
return 1;
if (new->pref > old->pref)
return 1;
if (new->pref < old->pref)
return 0;
if (new->attrs->proto->proto != old->attrs->proto->proto)
{
/*
* If the user has configured protocol preferences, so that two different protocols
* have the same preference, try to break the tie by comparing addresses. Not too
* useful, but keeps the ordering of routes unambiguous.
*/
return new->attrs->proto->proto > old->attrs->proto->proto;
}
if (better = new->attrs->proto->rte_better)
return better(new, old);
return 0;
}
static void
rte_trace(struct proto *p, rte *e, int dir, char *msg)
{
byte via[STD_ADDRESS_P_LENGTH+32];
rt_format_via(e, via);
log(L_TRACE "%s %c %s %I/%d %s", p->name, dir, msg, e->net->n.prefix, e->net->n.pxlen, via);
}
static inline void
rte_trace_in(unsigned int flag, struct proto *p, rte *e, char *msg)
{
if (p->debug & flag)
rte_trace(p, e, '>', msg);
}
static inline void
rte_trace_out(unsigned int flag, struct proto *p, rte *e, char *msg)
{
if (p->debug & flag)
rte_trace(p, e, '<', msg);
}
static inline void
do_rte_announce(struct announce_hook *a, int type, net *net, rte *new, rte *old, ea_list *tmpa, int class)
{
struct proto *p = a->proto;
rte *new0 = new;
rte *old0 = old;
int ok;
if (new)
{
char *drop_reason = NULL;
if ((class & IADDR_SCOPE_MASK) < p->min_scope)
drop_reason = "out of scope";
else if ((ok = p->import_control ? p->import_control(p, &new, &tmpa, rte_update_pool) : 0) < 0)
drop_reason = "rejected by protocol";
else if (ok)
rte_trace_out(D_FILTERS, p, new, "forced accept by protocol");
else if (p->out_filter == FILTER_REJECT ||
p->out_filter && f_run(p->out_filter, &new, &tmpa, rte_update_pool, FF_FORCE_TMPATTR) > F_ACCEPT)
drop_reason = "filtered out";
if (drop_reason)
{
rte_trace_out(D_FILTERS, p, new, drop_reason);
if (new != new0)
rte_free(new);
new = NULL;
}
}
if (old && p->out_filter)
{
if (p->out_filter == FILTER_REJECT)
old = NULL;
else
{
ea_list *tmpb = p->make_tmp_attrs ? p->make_tmp_attrs(old, rte_update_pool) : NULL;
ok = p->import_control ? p->import_control(p, &old, &tmpb, rte_update_pool) : 0;
if (ok < 0 || (!ok && f_run(p->out_filter, &old, &tmpb, rte_update_pool, FF_FORCE_TMPATTR) > F_ACCEPT))
{
if (old != old0)
rte_free(old);
old = NULL;
}
}
}
if (p->debug & D_ROUTES)
{
if (new && old)
rte_trace_out(D_ROUTES, p, new, "replaced");
else if (new)
rte_trace_out(D_ROUTES, p, new, "added");
else if (old)
rte_trace_out(D_ROUTES, p, old, "removed");
}
if (!new && !old)
return;
if (!new)
p->rt_notify(p, net, NULL, old, NULL);
else if (tmpa)
{
ea_list *t = tmpa;
while (t->next)
t = t->next;
t->next = new->attrs->eattrs;
p->rt_notify(p, net, new, old, tmpa);
t->next = NULL;
}
else
p->rt_notify(p, net, new, old, new->attrs->eattrs);
if (new && new != new0) /* Discard temporary rte's */
rte_free(new);
if (old && old != old0)
rte_free(old);
}
/**
* rte_announce - announce a routing table change
* @tab: table the route has been added to
* @type: type of route announcement (RA_OPTIMAL or RA_ANY)
* @net: network in question
* @new: the new route to be announced
* @old: the previous route for the same network
* @tmpa: a list of temporary attributes belonging to the new route
*
* This function gets a routing table update and announces it
* to all protocols that acccepts given type of route announcement
* and are connected to the same table by their announcement hooks.
*
* Route announcement of type RA_OPTIMAL si generated when optimal
* route (in routing table @tab) changes. In that case @old stores the
* old optimal route.
*
* Route announcement of type RA_ANY si generated when any route (in
* routing table @tab) changes In that case @old stores the old route
* from the same protocol.
*
* For each appropriate protocol, we first call its import_control()
* hook which performs basic checks on the route (each protocol has a
* right to veto or force accept of the route before any filter is
* asked) and adds default values of attributes specific to the new
* protocol (metrics, tags etc.). Then it consults the protocol's
* export filter and if it accepts the route, the rt_notify() hook of
* the protocol gets called.
*/
static void
rte_announce(rtable *tab, int type, net *net, rte *new, rte *old, ea_list *tmpa)
{
struct announce_hook *a;
int class = ipa_classify(net->n.prefix);
WALK_LIST(a, tab->hooks)
{
ASSERT(a->proto->core_state == FS_HAPPY || a->proto->core_state == FS_FEEDING);
if (a->proto->accept_ra_types == type)
do_rte_announce(a, type, net, new, old, tmpa, class);
}
}
static inline int
rte_validate(rte *e)
{
int c;
net *n = e->net;
if (ipa_nonzero(ipa_and(n->n.prefix, ipa_not(ipa_mkmask(n->n.pxlen)))))
{
log(L_BUG "Ignoring bogus prefix %I/%d received via %s",
n->n.prefix, n->n.pxlen, e->sender->name);
return 0;
}
if (n->n.pxlen)
{
c = ipa_classify(n->n.prefix);
if (c < 0 || !(c & IADDR_HOST))
{
if (!ipa_nonzero(n->n.prefix))
{
/* Various default routes */
#ifdef IPV6
if (n->n.pxlen == 96)
#else
if (n->n.pxlen <= 1)
#endif
return 1;
}
log(L_WARN "Ignoring bogus route %I/%d received via %s",
n->n.prefix, n->n.pxlen, e->sender->name);
return 0;
}
if ((c & IADDR_SCOPE_MASK) < e->sender->min_scope)
{
log(L_WARN "Ignoring %s scope route %I/%d received from %I via %s",
ip_scope_text(c & IADDR_SCOPE_MASK),
n->n.prefix, n->n.pxlen, e->attrs->from, e->sender->name);
return 0;
}
}
return 1;
}
/**
* rte_free - delete a &rte
* @e: &rte to be deleted
*
* rte_free() deletes the given &rte from the routing table it's linked to.
*/
void
rte_free(rte *e)
{
if (e->attrs->aflags & RTAF_CACHED)
rta_free(e->attrs);
sl_free(rte_slab, e);
}
static inline void
rte_free_quick(rte *e)
{
rta_free(e->attrs);
sl_free(rte_slab, e);
}
static int
rte_same(rte *x, rte *y)
{
return
x->attrs == y->attrs &&
x->flags == y->flags &&
x->pflags == y->pflags &&
x->pref == y->pref &&
(!x->attrs->proto->rte_same || x->attrs->proto->rte_same(x, y));
}
static void
rte_recalculate(rtable *table, net *net, struct proto *p, struct proto *src, rte *new, ea_list *tmpa)
{
rte *old_best = net->routes;
rte *old = NULL;
rte **k, *r, *s;
k = &net->routes; /* Find and remove original route from the same protocol */
while (old = *k)
{
if (old->attrs->proto == src)
{
if (new && rte_same(old, new))
{
/* No changes, ignore the new route */
rte_trace_in(D_ROUTES, p, new, "ignored");
rte_free_quick(new);
old->lastmod = now;
return;
}
*k = old->next;
break;
}
k = &old->next;
}
rte_announce(table, RA_ANY, net, new, old, tmpa);
if (new && rte_better(new, old_best)) /* It's a new optimal route => announce and relink it */
{
rte_trace_in(D_ROUTES, p, new, "added [best]");
rte_announce(table, RA_OPTIMAL, net, new, old_best, tmpa);
new->next = net->routes;
net->routes = new;
}
else
{
if (old == old_best) /* It has _replaced_ the old optimal route */
{
r = new; /* Find new optimal route and announce it */
for(s=net->routes; s; s=s->next)
if (rte_better(s, r))
r = s;
rte_announce(table, RA_OPTIMAL, net, r, old_best, tmpa);
if (r) /* Re-link the new optimal route */
{
k = &net->routes;
while (s = *k)
{
if (s == r)
{
*k = r->next;
break;
}
k = &s->next;
}
r->next = net->routes;
net->routes = r;
}
else if (table->gc_counter++ >= table->config->gc_max_ops &&
table->gc_time + table->config->gc_min_time <= now)
ev_schedule(table->gc_event);
}
if (new) /* Link in the new non-optimal route */
{
new->next = old_best->next;
old_best->next = new;
rte_trace_in(D_ROUTES, p, new, "added");
}
else if (old && (p->debug & D_ROUTES))
{
if (old != old_best)
rte_trace_in(D_ROUTES, p, old, "removed");
else if (net->routes)
rte_trace_in(D_ROUTES, p, old, "removed [replaced]");
else
rte_trace_in(D_ROUTES, p, old, "removed [sole]");
}
}
if (old)
{
if (p->rte_remove)
p->rte_remove(net, old);
rte_free_quick(old);
}
if (new)
{
new->lastmod = now;
if (p->rte_insert)
p->rte_insert(net, new);
}
}
static int rte_update_nest_cnt; /* Nesting counter to allow recursive updates */
static inline void
rte_update_lock(void)
{
rte_update_nest_cnt++;
}
static inline void
rte_update_unlock(void)
{
if (!--rte_update_nest_cnt)
lp_flush(rte_update_pool);
}
/**
* rte_update - enter a new update to a routing table
* @table: table to be updated
* @net: network node
* @p: protocol submitting the update
* @src: protocol originating the update
* @new: a &rte representing the new route or %NULL for route removal.
*
* This function is called by the routing protocols whenever they discover
* a new route or wish to update/remove an existing route. The right announcement
* sequence is to build route attributes first (either un-cached with @aflags set
* to zero or a cached one using rta_lookup(); in this case please note that
* you need to increase the use count of the attributes yourself by calling
* rta_clone()), call rte_get_temp() to obtain a temporary &rte, fill in all
* the appropriate data and finally submit the new &rte by calling rte_update().
*
* @src specifies the protocol that originally created the route and the meaning
* of protocol-dependent data of @new. If @new is not %NULL, @src have to be the
* same value as @new->attrs->proto. @p specifies the protocol that called
* rte_update(). In most cases it is the same protocol as @src. rte_update()
* stores @p in @new->sender;
*
* When rte_update() gets any route, it automatically validates it (checks,
* whether the network and next hop address are valid IP addresses and also
* whether a normal routing protocol doesn't try to smuggle a host or link
* scope route to the table), converts all protocol dependent attributes stored
* in the &rte to temporary extended attributes, consults import filters of the
* protocol to see if the route should be accepted and/or its attributes modified,
* stores the temporary attributes back to the &rte.
*
* Now, having a "public" version of the route, we
* automatically find any old route defined by the protocol @src
* for network @n, replace it by the new one (or removing it if @new is %NULL),
* recalculate the optimal route for this destination and finally broadcast
* the change (if any) to all routing protocols by calling rte_announce().
*
* All memory used for attribute lists and other temporary allocations is taken
* from a special linear pool @rte_update_pool and freed when rte_update()
* finishes.
*/
void
rte_update(rtable *table, net *net, struct proto *p, struct proto *src, rte *new)
{
ea_list *tmpa = NULL;
rte_update_lock();
if (new)
{
new->sender = p;
struct filter *filter = p->in_filter;
/* Do not filter routes going to the secondary side of the pipe,
that should only go through export filter.
FIXME Make a better check whether p is really a pipe. */
if (p->table != table)
filter = FILTER_ACCEPT;
if (!rte_validate(new))
{
rte_trace_in(D_FILTERS, p, new, "invalid");
goto drop;
}
if (filter == FILTER_REJECT)
{
rte_trace_in(D_FILTERS, p, new, "filtered out");
goto drop;
}
if (src->make_tmp_attrs)
tmpa = src->make_tmp_attrs(new, rte_update_pool);
if (filter)
{
ea_list *old_tmpa = tmpa;
int fr = f_run(filter, &new, &tmpa, rte_update_pool, 0);
if (fr > F_ACCEPT)
{
rte_trace_in(D_FILTERS, p, new, "filtered out");
goto drop;
}
if (tmpa != old_tmpa && src->store_tmp_attrs)
src->store_tmp_attrs(new, tmpa);
}
if (!(new->attrs->aflags & RTAF_CACHED)) /* Need to copy attributes */
new->attrs = rta_lookup(new->attrs);
new->flags |= REF_COW;
}
rte_recalculate(table, net, p, src, new, tmpa);
rte_update_unlock();
return;
drop:
rte_free(new);
rte_update_unlock();
}
void
rte_discard(rtable *t, rte *old) /* Non-filtered route deletion, used during garbage collection */
{
rte_update_lock();
rte_recalculate(t, old->net, old->sender, old->attrs->proto, NULL, NULL);
rte_update_unlock();
}
/**
* rte_dump - dump a route
* @e: &rte to be dumped
*
* This functions dumps contents of a &rte to debug output.
*/
void
rte_dump(rte *e)
{
net *n = e->net;
if (n)
debug("%-1I/%2d ", n->n.prefix, n->n.pxlen);
else
debug("??? ");
debug("KF=%02x PF=%02x pref=%d lm=%d ", n->n.flags, e->pflags, e->pref, now-e->lastmod);
rta_dump(e->attrs);
if (e->attrs->proto->proto->dump_attrs)
e->attrs->proto->proto->dump_attrs(e);
debug("\n");
}
/**
* rt_dump - dump a routing table
* @t: routing table to be dumped
*
* This function dumps contents of a given routing table to debug output.
*/
void
rt_dump(rtable *t)
{
rte *e;
net *n;
struct announce_hook *a;
debug("Dump of routing table <%s>\n", t->name);
#ifdef DEBUGGING
fib_check(&t->fib);
#endif
FIB_WALK(&t->fib, fn)
{
n = (net *) fn;
for(e=n->routes; e; e=e->next)
rte_dump(e);
}
FIB_WALK_END;
WALK_LIST(a, t->hooks)
debug("\tAnnounces routes to protocol %s\n", a->proto->name);
debug("\n");
}
/**
* rt_dump_all - dump all routing tables
*
* This function dumps contents of all routing tables to debug output.
*/
void
rt_dump_all(void)
{
rtable *t;
WALK_LIST(t, routing_tables)
rt_dump(t);
}
static void
rt_gc(void *tab)
{
rtable *t = tab;
DBG("Entered routing table garbage collector for %s after %d seconds and %d deletes\n",
t->name, (int)(now - t->gc_time), t->gc_counter);
rt_prune(t);
}
void
rt_setup(pool *p, rtable *t, char *name, struct rtable_config *cf)
{
bzero(t, sizeof(*t));
fib_init(&t->fib, p, sizeof(net), 0, rte_init);
t->name = name;
t->config = cf;
init_list(&t->hooks);
if (cf)
{
t->gc_event = ev_new(p);
t->gc_event->hook = rt_gc;
t->gc_event->data = t;
t->gc_time = now;
}
}
/**
* rt_init - initialize routing tables
*
* This function is called during BIRD startup. It initializes the
* routing table module.
*/
void
rt_init(void)
{
rta_init();
rt_table_pool = rp_new(&root_pool, "Routing tables");
rte_update_pool = lp_new(rt_table_pool, 4080);
rte_slab = sl_new(rt_table_pool, sizeof(rte));
init_list(&routing_tables);
}
/**
* rt_prune - prune a routing table
* @tab: routing table to be pruned
*
* This function is called whenever a protocol shuts down. It scans
* the routing table and removes all routes belonging to inactive
* protocols and also stale network entries.
*/
void
rt_prune(rtable *tab)
{
struct fib_iterator fit;
int rcnt = 0, rdel = 0, ncnt = 0, ndel = 0;
DBG("Pruning route table %s\n", tab->name);
#ifdef DEBUGGING
fib_check(&tab->fib);
#endif
FIB_ITERATE_INIT(&fit, &tab->fib);
again:
FIB_ITERATE_START(&tab->fib, &fit, f)
{
net *n = (net *) f;
rte *e;
ncnt++;
rescan:
for (e=n->routes; e; e=e->next, rcnt++)
if (e->sender->core_state != FS_HAPPY &&
e->sender->core_state != FS_FEEDING)
{
rte_discard(tab, e);
rdel++;
goto rescan;
}
if (!n->routes) /* Orphaned FIB entry? */
{
FIB_ITERATE_PUT(&fit, f);
fib_delete(&tab->fib, f);
ndel++;
goto again;
}
}
FIB_ITERATE_END(f);
DBG("Pruned %d of %d routes and %d of %d networks\n", rdel, rcnt, ndel, ncnt);
#ifdef DEBUGGING
fib_check(&tab->fib);
#endif
tab->gc_counter = 0;
tab->gc_time = now;
}
/**
* rt_prune_all - prune all routing tables
*
* This function calls rt_prune() for all known routing tables.
*/
void
rt_prune_all(void)
{
rtable *t;
WALK_LIST(t, routing_tables)
rt_prune(t);
}
struct rtable_config *
rt_new_table(struct symbol *s)
{
struct rtable_config *c = cfg_allocz(sizeof(struct rtable_config));
cf_define_symbol(s, SYM_TABLE, c);
c->name = s->name;
add_tail(&new_config->tables, &c->n);
c->gc_max_ops = 1000;
c->gc_min_time = 5;
return c;
}
void
rt_preconfig(struct config *c)
{
struct symbol *s = cf_find_symbol("master");
init_list(&c->tables);
c->master_rtc = rt_new_table(s);
}
/**
* rt_lock_table - lock a routing table
* @r: routing table to be locked
*
* Lock a routing table, because it's in use by a protocol,
* preventing it from being freed when it gets undefined in a new
* configuration.
*/
void
rt_lock_table(rtable *r)
{
r->use_count++;
}
/**
* rt_unlock_table - unlock a routing table
* @r: routing table to be unlocked
*
* Unlock a routing table formerly locked by rt_lock_table(),
* that is decrease its use count and delete it if it's scheduled
* for deletion by configuration changes.
*/
void
rt_unlock_table(rtable *r)
{
if (!--r->use_count && r->deleted)
{
struct config *conf = r->deleted;
DBG("Deleting routing table %s\n", r->name);
rem_node(&r->n);
fib_free(&r->fib);
mb_free(r);
config_del_obstacle(conf);
}
}
/**
* rt_commit - commit new routing table configuration
* @new: new configuration
* @old: original configuration or %NULL if it's boot time config
*
* Scan differences between @old and @new configuration and modify
* the routing tables according to these changes. If @new defines a
* previously unknown table, create it, if it omits a table existing
* in @old, schedule it for deletion (it gets deleted when all protocols
* disconnect from it by calling rt_unlock_table()), if it exists
* in both configurations, leave it unchanged.
*/
void
rt_commit(struct config *new, struct config *old)
{
struct rtable_config *o, *r;
DBG("rt_commit:\n");
if (old)
{
WALK_LIST(o, old->tables)
{
rtable *ot = o->table;
if (!ot->deleted)
{
struct symbol *sym = cf_find_symbol(o->name);
if (sym && sym->class == SYM_TABLE && !new->shutdown)
{
DBG("\t%s: same\n", o->name);
r = sym->def;
r->table = ot;
ot->name = r->name;
ot->config = r;
}
else
{
DBG("\t%s: deleted\n", o->name);
ot->deleted = old;
config_add_obstacle(old);
rt_lock_table(ot);
rt_unlock_table(ot);
}
}
}
}
WALK_LIST(r, new->tables)
if (!r->table)
{
rtable *t = mb_alloc(rt_table_pool, sizeof(struct rtable));
DBG("\t%s: created\n", r->name);
rt_setup(rt_table_pool, t, r->name, r);
add_tail(&routing_tables, &t->n);
r->table = t;
}
DBG("\tdone\n");
}
static inline void
do_feed_baby(struct proto *p, int type, struct announce_hook *h, net *n, rte *e)
{
struct proto *q = e->attrs->proto;
ea_list *tmpa;
rte_update_lock();
tmpa = q->make_tmp_attrs ? q->make_tmp_attrs(e, rte_update_pool) : NULL;
do_rte_announce(h, type, n, e, NULL, tmpa, ipa_classify(n->n.prefix));
rte_update_unlock();
}
/**
* rt_feed_baby - advertise routes to a new protocol
* @p: protocol to be fed
*
* This function performs one pass of advertisement of routes to a newly
* initialized protocol. It's called by the protocol code as long as it
* has something to do. (We avoid transferring all the routes in single
* pass in order not to monopolize CPU time.)
*/
int
rt_feed_baby(struct proto *p)
{
struct announce_hook *h;
struct fib_iterator *fit;
int max_feed = 256;
if (!p->feed_ahook) /* Need to initialize first */
{
if (!p->ahooks)
return 1;
DBG("Announcing routes to new protocol %s\n", p->name);
p->feed_ahook = p->ahooks;
fit = p->feed_iterator = mb_alloc(p->pool, sizeof(struct fib_iterator));
goto next_hook;
}
fit = p->feed_iterator;
again:
h = p->feed_ahook;
FIB_ITERATE_START(&h->table->fib, fit, fn)
{
net *n = (net *) fn;
rte *e = n->routes;
if (max_feed <= 0)
{
FIB_ITERATE_PUT(fit, fn);
return 0;
}
if (p->accept_ra_types == RA_OPTIMAL)
if (e)
{
if (p->core_state != FS_FEEDING)
return 1; /* In the meantime, the protocol fell down. */
do_feed_baby(p, RA_OPTIMAL, h, n, e);
max_feed--;
}
if (p->accept_ra_types == RA_ANY)
for(e = n->routes; e != NULL; e = e->next)
{
if (p->core_state != FS_FEEDING)
return 1; /* In the meantime, the protocol fell down. */
do_feed_baby(p, RA_ANY, h, n, e);
max_feed--;
}
}
FIB_ITERATE_END(fn);
p->feed_ahook = h->next;
if (!p->feed_ahook)
{
mb_free(p->feed_iterator);
p->feed_iterator = NULL;
return 1;
}
next_hook:
h = p->feed_ahook;
FIB_ITERATE_INIT(fit, &h->table->fib);
goto again;
}
/**
* rt_feed_baby_abort - abort protocol feeding
* @p: protocol
*
* This function is called by the protocol code when the protocol
* stops or ceases to exist before the last iteration of rt_feed_baby()
* has finished.
*/
void
rt_feed_baby_abort(struct proto *p)
{
if (p->feed_ahook)
{
/* Unlink the iterator and exit */
fit_get(&p->feed_ahook->table->fib, p->feed_iterator);
p->feed_ahook = NULL;
}
}
/*
* CLI commands
*/
static void
rt_format_via(rte *e, byte *via)
{
rta *a = e->attrs;
switch (a->dest)
{
case RTD_ROUTER: bsprintf(via, "via %I on %s", a->gw, a->iface->name); break;
case RTD_DEVICE: bsprintf(via, "dev %s", a->iface->name); break;
case RTD_BLACKHOLE: bsprintf(via, "blackhole"); break;
case RTD_UNREACHABLE: bsprintf(via, "unreachable"); break;
case RTD_PROHIBIT: bsprintf(via, "prohibited"); break;
default: bsprintf(via, "???");
}
}
static void
rt_show_rte(struct cli *c, byte *ia, rte *e, struct rt_show_data *d, ea_list *tmpa)
{
byte via[STD_ADDRESS_P_LENGTH+32], from[STD_ADDRESS_P_LENGTH+6];
byte tm[TM_RELTIME_BUFFER_SIZE], info[256];
rta *a = e->attrs;
rt_format_via(e, via);
tm_format_reltime(tm, e->lastmod);
if (ipa_nonzero(a->from) && !ipa_equal(a->from, a->gw))
bsprintf(from, " from %I", a->from);
else
from[0] = 0;
if (a->proto->proto->get_route_info || d->verbose)
{
/* Need to normalize the extended attributes */
ea_list *t = tmpa;
t = ea_append(t, a->eattrs);
tmpa = alloca(ea_scan(t));
ea_merge(t, tmpa);
ea_sort(tmpa);
}
if (a->proto->proto->get_route_info)
a->proto->proto->get_route_info(e, info, tmpa);
else
bsprintf(info, " (%d)", e->pref);
cli_printf(c, -1007, "%-18s %s [%s %s%s]%s", ia, via, a->proto->name, tm, from, info);
if (d->verbose)
rta_show(c, a, tmpa);
}
static void
rt_show_net(struct cli *c, net *n, struct rt_show_data *d)
{
rte *e, *ee;
byte ia[STD_ADDRESS_P_LENGTH+8];
int ok;
bsprintf(ia, "%I/%d", n->n.prefix, n->n.pxlen);
if (n->routes)
d->net_counter++;
for(e=n->routes; e; e=e->next)
{
struct ea_list *tmpa, *old_tmpa;
struct proto *p0 = e->attrs->proto;
struct proto *p1 = d->export_protocol;
struct proto *p2 = d->show_protocol;
d->rt_counter++;
ee = e;
rte_update_lock(); /* We use the update buffer for filtering */
old_tmpa = tmpa = p0->make_tmp_attrs ? p0->make_tmp_attrs(e, rte_update_pool) : NULL;
ok = (d->filter == FILTER_ACCEPT || f_run(d->filter, &e, &tmpa, rte_update_pool, FF_FORCE_TMPATTR) <= F_ACCEPT);
if (p2 && p2 != p0) ok = 0;
if (ok && d->export_mode)
{
int ic = (p1->import_control ? p1->import_control(p1, &e, &tmpa, rte_update_pool) : 0);
if (ic < 0)
ok = 0;
else if (!ic && d->export_mode > 1)
{
if (p1->out_filter == FILTER_REJECT ||
p1->out_filter && f_run(p1->out_filter, &e, &tmpa, rte_update_pool, FF_FORCE_TMPATTR) > F_ACCEPT)
ok = 0;
}
}
if (ok)
{
d->show_counter++;
if (d->stats < 2)
rt_show_rte(c, ia, e, d, tmpa);
ia[0] = 0;
}
if (e != ee)
rte_free(ee);
rte_update_unlock();
if (d->primary_only)
break;
}
}
static void
rt_show_cont(struct cli *c)
{
struct rt_show_data *d = c->rover;
#ifdef DEBUGGING
unsigned max = 4;
#else
unsigned max = 64;
#endif
struct fib *fib = &d->table->fib;
struct fib_iterator *it = &d->fit;
FIB_ITERATE_START(fib, it, f)
{
net *n = (net *) f;
if (d->running_on_config && d->running_on_config != config)
{
cli_printf(c, 8004, "Stopped due to reconfiguration");
goto done;
}
if (d->export_protocol &&
d->export_protocol->core_state != FS_HAPPY &&
d->export_protocol->core_state != FS_FEEDING)
{
cli_printf(c, 8005, "Protocol is down");
goto done;
}
if (!max--)
{
FIB_ITERATE_PUT(it, f);
return;
}
rt_show_net(c, n, d);
}
FIB_ITERATE_END(f);
if (d->stats)
cli_printf(c, 14, "%d of %d routes for %d networks", d->show_counter, d->rt_counter, d->net_counter);
else
cli_printf(c, 0, "");
done:
c->cont = c->cleanup = NULL;
}
static void
rt_show_cleanup(struct cli *c)
{
struct rt_show_data *d = c->rover;
/* Unlink the iterator */
fit_get(&d->table->fib, &d->fit);
}
void
rt_show(struct rt_show_data *d)
{
net *n;
if (d->pxlen == 256)
{
FIB_ITERATE_INIT(&d->fit, &d->table->fib);
this_cli->cont = rt_show_cont;
this_cli->cleanup = rt_show_cleanup;
this_cli->rover = d;
}
else
{
if (d->show_for)
n = fib_route(&d->table->fib, d->prefix, d->pxlen);
else
n = fib_find(&d->table->fib, &d->prefix, d->pxlen);
if (n)
{
rt_show_net(this_cli, n, d);
cli_msg(0, "");
}
else
cli_msg(8001, "Network not in table");
}
}
/*
* Documentation for functions declared inline in route.h
*/
#if 0
/**
* net_find - find a network entry
* @tab: a routing table
* @addr: address of the network
* @len: length of the network prefix
*
* net_find() looks up the given network in routing table @tab and
* returns a pointer to its &net entry or %NULL if no such network
* exists.
*/
static inline net *net_find(rtable *tab, ip_addr addr, unsigned len)
{ DUMMY; }
/**
* net_get - obtain a network entry
* @tab: a routing table
* @addr: address of the network
* @len: length of the network prefix
*
* net_get() looks up the given network in routing table @tab and
* returns a pointer to its &net entry. If no such entry exists, it's
* created.
*/
static inline net *net_get(rtable *tab, ip_addr addr, unsigned len)
{ DUMMY; }
/**
* rte_cow - copy a route for writing
* @r: a route entry to be copied
*
* rte_cow() takes a &rte and prepares it for modification. The exact action
* taken depends on the flags of the &rte -- if it's a temporary entry, it's
* just returned unchanged, else a new temporary entry with the same contents
* is created.
*
* The primary use of this function is inside the filter machinery -- when
* a filter wants to modify &rte contents (to change the preference or to
* attach another set of attributes), it must ensure that the &rte is not
* shared with anyone else (and especially that it isn't stored in any routing
* table).
*
* Result: a pointer to the new writable &rte.
*/
static inline rte * rte_cow(rte *r)
{ DUMMY; }
#endif
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