Added `show route for <prefix-or-ipa>' which looks up route leading to

given network.

TODO

@@ -10,7 +10,6 @@ Core
 - filters: user defined attributes?
 
 - cli: show tables?
-- cli: show where is routed given IP address?
 
 - client: Ctrl-R eats one more enter
 - client: paging?

nest/config.Y

@@ -22,7 +22,7 @@ CF_DECLS
 CF_KEYWORDS(ROUTER, ID, PROTOCOL, PREFERENCE, DISABLED, DEBUG, ALL, OFF, DIRECT)
 CF_KEYWORDS(INTERFACE, IMPORT, EXPORT, FILTER, NONE, TABLE, STATES, ROUTES, FILTERS)
 CF_KEYWORDS(PASSWORD, FROM, PASSIVE, TO, ID, EVENTS, PACKETS, PROTOCOLS, INTERFACES)
-CF_KEYWORDS(PRIMARY, STATS, COUNT)
+CF_KEYWORDS(PRIMARY, STATS, COUNT, FOR)
 
 CF_ENUM(T_ENUM_RTS, RTS_, DUMMY, STATIC, INHERIT, DEVICE, STATIC_DEVICE, REDIRECT,
 	RIP, OSPF, OSPF_EXT, OSPF_IA, OSPF_BOUNDARY, BGP, PIPE)
@@ -256,6 +256,13 @@ r_args:
      $$->prefix = $2.addr;
      $$->pxlen = $2.len;
    }
+ | r_args FOR prefix_or_ipa {
+     $$ = $1;
+     if ($$->pxlen != 256) cf_error("Only one prefix expected");
+     $$->prefix = $3.addr;
+     $$->pxlen = $3.len;
+     $$->show_for = 1;
+   }
  | r_args TABLE SYM {
      $$ = $1;
      if ($3->class != SYM_TABLE) cf_error("%s is not a table", $3->name);

nest/rt-table.c

@@ -846,6 +846,9 @@ rt_show(struct rt_show_data *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)
 	{