bird/nest/rt-show.c
Jan Maria Matejka 14375237f6 Terminology cleanup: The import_control hook is now called preexport.
Once upon a time, far far away, there were the old Bird developers
discussing what direction of route flow shall be called import and
export. They decided to say "import to protocol" and "export to table"
when speaking about a protocol. When speaking about a table, they
spoke about "importing to table" and "exporting to protocol".

The latter terminology was adopted in configuration, then also the
bird CLI in commit ea2ae6dd0 started to use it (in year 2009). Now
it's 2018 and the terminology is the latter. Import is from protocol to
table, export is from table to protocol. Anyway, there was still an
import_control hook which executed right before route export.

One thing is funny. There are two commits in April 1999 with just two
minutes between them. The older announces the final settlement
on config terminology, the newer uses the other definition. Let's see
their commit messages as the git-log tool shows them (the newer first):

    commit 9e0e485e50
    Author: Martin Mares <mj@ucw.cz>
    Date:   Mon Apr 5 20:17:59 1999 +0000

	Added some new protocol hooks (look at the comments for better explanation):

		make_tmp_attrs          Convert inline attributes to ea_list
		store_tmp_attrs         Convert ea_list to inline attributes
		import_control          Pre-import decisions

    commit 5056c559c4
    Author: Martin Mares <mj@ucw.cz>
    Date:   Mon Apr 5 20:15:31 1999 +0000

	Changed syntax of attaching filters to protocols to hopefully the final
	version:

		EXPORT <filter-spec>    for outbound routes (i.e., those announced
					by BIRD to the rest of the world).
		IMPORT <filter-spec>    for inbound routes (i.e., those imported
					by BIRD from the rest of the world).

	where <filter-spec> is one of:

		ALL                     pass all routes
		NONE                    drop all routes
		FILTER <name>           use named filter
		FILTER { <filter> }     use explicitly defined filter

	For all protocols, the default is IMPORT ALL, EXPORT NONE. This includes
	the kernel protocol, so that you need to add EXPORT ALL to get the previous
	configuration of kernel syncer (as usually, see doc/bird.conf.example for
	a bird.conf example :)).

Let's say RIP to this almost 19-years-old inconsistency. For now, if you
import a route, it is always from protocol to table. If you export a
route, it is always from table to protocol.

And they lived happily ever after.
2018-12-04 10:53:01 +01:00

413 lines
9.4 KiB
C

/*
* BIRD -- Route Display Routines
*
* (c) 1998--2000 Martin Mares <mj@ucw.cz>
* (c) 2017 Jan Moskyto Matejka <mq@jmq.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#undef LOCAL_DEBUG
#include "nest/bird.h"
#include "nest/route.h"
#include "nest/protocol.h"
#include "nest/cli.h"
#include "nest/iface.h"
#include "filter/filter.h"
static void
rt_show_table(struct cli *c, struct rt_show_data *d)
{
/* No table blocks in 'show route count' */
if (d->stats == 2)
return;
if (d->last_table) cli_printf(c, -1007, "");
cli_printf(c, -1007, "Table %s:", d->tab->table->name);
d->last_table = d->tab;
}
static void
rt_show_rte(struct cli *c, byte *ia, rte *e, struct rt_show_data *d)
{
byte from[IPA_MAX_TEXT_LENGTH+8];
byte tm[TM_DATETIME_BUFFER_SIZE], info[256];
rta *a = e->attrs;
int primary = (e->net->routes == e);
int sync_error = (e->net->n.flags & KRF_SYNC_ERROR);
void (*get_route_info)(struct rte *, byte *buf);
struct nexthop *nh;
tm_format_time(tm, &config->tf_route, e->lastmod);
if (ipa_nonzero(a->from) && !ipa_equal(a->from, a->nh.gw))
bsprintf(from, " from %I", a->from);
else
from[0] = 0;
get_route_info = a->src->proto->proto->get_route_info;
/* Need to normalize the extended attributes */
if ((get_route_info || d->verbose) && !rta_is_cached(a))
ea_normalize(a->eattrs);
if (get_route_info)
get_route_info(e, info);
else
bsprintf(info, " (%d)", e->pref);
if (d->last_table != d->tab)
rt_show_table(c, d);
cli_printf(c, -1007, "%-20s %s [%s %s%s]%s%s", ia, rta_dest_name(a->dest),
a->src->proto->name, tm, from, primary ? (sync_error ? " !" : " *") : "", info);
if (a->dest == RTD_UNICAST)
for (nh = &(a->nh); nh; nh = nh->next)
{
char mpls[MPLS_MAX_LABEL_STACK*12 + 5], *lsp = mpls;
char *onlink = (nh->flags & RNF_ONLINK) ? " onlink" : "";
char weight[16] = "";
if (nh->labels)
{
lsp += bsprintf(lsp, " mpls %d", nh->label[0]);
for (int i=1;i<nh->labels; i++)
lsp += bsprintf(lsp, "/%d", nh->label[i]);
}
*lsp = '\0';
if (a->nh.next)
bsprintf(weight, " weight %d", nh->weight + 1);
if (ipa_nonzero(nh->gw))
cli_printf(c, -1007, "\tvia %I on %s%s%s%s",
nh->gw, nh->iface->name, mpls, onlink, weight);
else
cli_printf(c, -1007, "\tdev %s%s%s",
nh->iface->name, mpls, onlink, weight);
}
if (d->verbose)
rta_show(c, a);
}
static void
rt_show_net(struct cli *c, net *n, struct rt_show_data *d)
{
rte *e, *ee;
byte ia[NET_MAX_TEXT_LENGTH+1];
struct channel *ec = d->tab->export_channel;
int first = 1;
int pass = 0;
bsnprintf(ia, sizeof(ia), "%N", n->n.addr);
for (e = n->routes; e; e = e->next)
{
if (rte_is_filtered(e) != d->filtered)
continue;
d->rt_counter++;
d->net_counter += first;
first = 0;
if (pass)
continue;
ee = e;
rte_make_tmp_attrs(&e, c->show_pool);
/* Export channel is down, do not try to export routes to it */
if (ec && (ec->export_state == ES_DOWN))
goto skip;
/* Special case for merged export */
if ((d->export_mode == RSEM_EXPORT) && (ec->ra_mode == RA_MERGED))
{
rte *rt_free;
e = rt_export_merged(ec, n, &rt_free, c->show_pool, 1);
pass = 1;
if (!e)
{ e = ee; goto skip; }
}
else if (d->export_mode)
{
struct proto *ep = ec->proto;
int ic = ep->preexport ? ep->preexport(ep, &e, c->show_pool) : 0;
if (ec->ra_mode == RA_OPTIMAL || ec->ra_mode == RA_MERGED)
pass = 1;
if (ic < 0)
goto skip;
if (d->export_mode > RSEM_PREEXPORT)
{
/*
* FIXME - This shows what should be exported according to current
* filters, but not what was really exported. 'configure soft'
* command may change the export filter and do not update routes.
*/
int do_export = (ic > 0) ||
(f_run(ec->out_filter, &e, c->show_pool, FF_SILENT) <= F_ACCEPT);
if (do_export != (d->export_mode == RSEM_EXPORT))
goto skip;
if ((d->export_mode == RSEM_EXPORT) && (ec->ra_mode == RA_ACCEPTED))
pass = 1;
}
}
if (d->show_protocol && (d->show_protocol != e->attrs->src->proto))
goto skip;
if (f_run(d->filter, &e, c->show_pool, 0) > F_ACCEPT)
goto skip;
if (d->stats < 2)
rt_show_rte(c, ia, e, d);
d->show_counter++;
ia[0] = 0;
skip:
if (e != ee)
{
rte_free(e);
e = ee;
}
lp_flush(c->show_pool);
if (d->primary_only)
break;
}
}
static void
rt_show_cleanup(struct cli *c)
{
struct rt_show_data *d = c->rover;
struct rt_show_data_rtable *tab;
/* Unlink the iterator */
if (d->table_open)
fit_get(&d->tab->table->fib, &d->fit);
/* Unlock referenced tables */
WALK_LIST(tab, d->tables)
rt_unlock_table(tab->table);
}
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->tab->table->fib;
struct fib_iterator *it = &d->fit;
if (d->running_on_config && (d->running_on_config != config))
{
cli_printf(c, 8004, "Stopped due to reconfiguration");
goto done;
}
if (!d->table_open)
{
FIB_ITERATE_INIT(&d->fit, &d->tab->table->fib);
d->table_open = 1;
d->table_counter++;
d->show_counter_last = d->show_counter;
d->rt_counter_last = d->rt_counter;
d->net_counter_last = d->net_counter;
if (d->tables_defined_by & RSD_TDB_SET)
rt_show_table(c, d);
}
FIB_ITERATE_START(fib, it, net, n)
{
if (!max--)
{
FIB_ITERATE_PUT(it);
return;
}
rt_show_net(c, n, d);
}
FIB_ITERATE_END;
if (d->stats)
{
if (d->last_table != d->tab)
rt_show_table(c, d);
cli_printf(c, -1007, "%d of %d routes for %d networks in table %s",
d->show_counter - d->show_counter_last, d->rt_counter - d->rt_counter_last,
d->net_counter - d->net_counter_last, d->tab->table->name);
}
d->table_open = 0;
d->tab = NODE_NEXT(d->tab);
if (NODE_VALID(d->tab))
return;
if (d->stats && (d->table_counter > 1))
{
if (d->last_table) cli_printf(c, -1007, "");
cli_printf(c, 14, "Total: %d of %d routes for %d networks in %d tables",
d->show_counter, d->rt_counter, d->net_counter, d->table_counter);
}
else
cli_printf(c, 0, "");
done:
rt_show_cleanup(c);
c->cont = c->cleanup = NULL;
}
struct rt_show_data_rtable *
rt_show_add_table(struct rt_show_data *d, rtable *t)
{
struct rt_show_data_rtable *tab = cfg_allocz(sizeof(struct rt_show_data_rtable));
tab->table = t;
add_tail(&(d->tables), &(tab->n));
return tab;
}
static inline void
rt_show_get_default_tables(struct rt_show_data *d)
{
struct channel *c;
struct rt_show_data_rtable *tab;
if (d->export_channel)
{
c = d->export_channel;
tab = rt_show_add_table(d, c->table);
tab->export_channel = c;
return;
}
if (d->export_protocol)
{
WALK_LIST(c, d->export_protocol->channels)
{
if (c->export_state == ES_DOWN)
continue;
tab = rt_show_add_table(d, c->table);
tab->export_channel = c;
}
return;
}
if (d->show_protocol)
{
WALK_LIST(c, d->show_protocol->channels)
rt_show_add_table(d, c->table);
return;
}
for (int i=1; i<NET_MAX; i++)
if (config->def_tables[i])
rt_show_add_table(d, config->def_tables[i]->table);
}
static inline void
rt_show_prepare_tables(struct rt_show_data *d)
{
struct rt_show_data_rtable *tab, *tabx;
/* Add implicit tables if no table is specified */
if (EMPTY_LIST(d->tables))
rt_show_get_default_tables(d);
WALK_LIST_DELSAFE(tab, tabx, d->tables)
{
/* Ensure there is defined export_channel for each table */
if (d->export_mode)
{
if (!tab->export_channel && d->export_channel &&
(tab->table == d->export_channel->table))
tab->export_channel = d->export_channel;
if (!tab->export_channel && d->export_protocol)
tab->export_channel = proto_find_channel_by_table(d->export_protocol, tab->table);
if (!tab->export_channel)
{
if (d->tables_defined_by & RSD_TDB_NMN)
cf_error("No export channel for table %s", tab->table->name);
rem_node(&(tab->n));
continue;
}
}
/* Ensure specified network is compatible with each table */
if (d->addr && (tab->table->addr_type != d->addr->type))
{
if (d->tables_defined_by & RSD_TDB_NMN)
cf_error("Incompatible type of prefix/ip for table %s", tab->table->name);
rem_node(&(tab->n));
continue;
}
}
/* Ensure there is at least one table */
if (EMPTY_LIST(d->tables))
cf_error("No valid tables");
}
void
rt_show(struct rt_show_data *d)
{
struct rt_show_data_rtable *tab;
net *n;
/* Filtered routes are neither exported nor have sensible ordering */
if (d->filtered && (d->export_mode || d->primary_only))
cf_error("Incompatible show route options");
rt_show_prepare_tables(d);
if (!d->addr)
{
WALK_LIST(tab, d->tables)
rt_lock_table(tab->table);
/* There is at least one table */
d->tab = HEAD(d->tables);
this_cli->cont = rt_show_cont;
this_cli->cleanup = rt_show_cleanup;
this_cli->rover = d;
}
else
{
WALK_LIST(tab, d->tables)
{
d->tab = tab;
if (d->show_for)
n = net_route(tab->table, d->addr);
else
n = net_find(tab->table, d->addr);
if (n)
rt_show_net(this_cli, n, d);
}
if (d->rt_counter)
cli_msg(0, "");
else
cli_msg(8001, "Network not found");
}
}