bird/nest/proto.c
2015-06-08 02:24:08 +02:00

1703 lines
44 KiB
C

/*
* BIRD -- Protocols
*
* (c) 1998--2000 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#undef LOCAL_DEBUG
#include "nest/bird.h"
#include "nest/protocol.h"
#include "lib/resource.h"
#include "lib/lists.h"
#include "lib/event.h"
#include "lib/string.h"
#include "conf/conf.h"
#include "nest/route.h"
#include "nest/iface.h"
#include "nest/cli.h"
#include "filter/filter.h"
pool *proto_pool;
static list protocol_list;
static list proto_list;
#define PD(pr, msg, args...) do { if (pr->debug & D_STATES) { log(L_TRACE "%s: " msg, pr->name , ## args); } } while(0)
list active_proto_list;
static list inactive_proto_list;
static list initial_proto_list;
static list flush_proto_list;
static struct proto *initial_device_proto;
static event *proto_flush_event;
static timer *proto_shutdown_timer;
static timer *gr_wait_timer;
#define GRS_NONE 0
#define GRS_INIT 1
#define GRS_ACTIVE 2
#define GRS_DONE 3
static int graceful_restart_state;
static u32 graceful_restart_locks;
static char *p_states[] = { "DOWN", "START", "UP", "STOP" };
static char *c_states[] = { "HUNGRY", "???", "HAPPY", "FLUSHING" };
static void proto_flush_loop(void *);
static void proto_shutdown_loop(struct timer *);
static void proto_rethink_goal(struct proto *p);
static void proto_want_export_up(struct proto *p);
static void proto_fell_down(struct proto *p);
static char *proto_state_name(struct proto *p);
static void
proto_relink(struct proto *p)
{
list *l = NULL;
switch (p->core_state)
{
case FS_HUNGRY:
l = &inactive_proto_list;
break;
case FS_HAPPY:
l = &active_proto_list;
break;
case FS_FLUSHING:
l = &flush_proto_list;
break;
default:
ASSERT(0);
}
rem_node(&p->n);
add_tail(l, &p->n);
}
static void
proto_log_state_change(struct proto *p)
{
if (p->debug & D_STATES)
{
char *name = proto_state_name(p);
if (name != p->last_state_name_announced)
{
p->last_state_name_announced = name;
PD(p, "State changed to %s", proto_state_name(p));
}
}
else
p->last_state_name_announced = NULL;
}
/**
* proto_new - create a new protocol instance
* @c: protocol configuration
* @size: size of protocol data structure (each protocol instance is represented by
* a structure starting with generic part [struct &proto] and continued
* with data specific to the protocol)
*
* When a new configuration has been read in, the core code starts
* initializing all the protocol instances configured by calling their
* init() hooks with the corresponding instance configuration. The initialization
* code of the protocol is expected to create a new instance according to the
* configuration by calling this function and then modifying the default settings
* to values wanted by the protocol.
*/
void *
proto_new(struct proto_config *c, unsigned size)
{
struct protocol *pr = c->protocol;
struct proto *p = mb_allocz(proto_pool, size);
p->cf = c;
p->debug = c->debug;
p->mrtdump = c->mrtdump;
p->name = c->name;
p->preference = c->preference;
p->disabled = c->disabled;
p->proto = pr;
p->table = c->table->table;
p->hash_key = random_u32();
c->proto = p;
return p;
}
static void
proto_init_instance(struct proto *p)
{
/* Here we cannot use p->cf->name since it won't survive reconfiguration */
p->pool = rp_new(proto_pool, p->proto->name);
p->attn = ev_new(p->pool);
p->attn->data = p;
if (graceful_restart_state == GRS_INIT)
p->gr_recovery = 1;
if (! p->proto->multitable)
rt_lock_table(p->table);
}
extern pool *rt_table_pool;
/**
* proto_add_announce_hook - connect protocol to a routing table
* @p: protocol instance
* @t: routing table to connect to
* @stats: per-table protocol statistics
*
* This function creates a connection between the protocol instance @p and the
* routing table @t, making the protocol hear all changes in the table.
*
* The announce hook is linked in the protocol ahook list. Announce hooks are
* allocated from the routing table resource pool and when protocol accepts
* routes also in the table ahook list. The are linked to the table ahook list
* and unlinked from it depending on export_state (in proto_want_export_up() and
* proto_want_export_down()) and they are automatically freed after the protocol
* is flushed (in proto_fell_down()).
*
* Unless you want to listen to multiple routing tables (as the Pipe protocol
* does), you needn't to worry about this function since the connection to the
* protocol's primary routing table is initialized automatically by the core
* code.
*/
struct announce_hook *
proto_add_announce_hook(struct proto *p, struct rtable *t, struct proto_stats *stats)
{
struct announce_hook *h;
DBG("Connecting protocol %s to table %s\n", p->name, t->name);
PD(p, "Connected to table %s", t->name);
h = mb_allocz(rt_table_pool, sizeof(struct announce_hook));
h->table = t;
h->proto = p;
h->stats = stats;
h->next = p->ahooks;
p->ahooks = h;
if (p->rt_notify && (p->export_state != ES_DOWN))
add_tail(&t->hooks, &h->n);
return h;
}
/**
* proto_find_announce_hook - find announce hooks
* @p: protocol instance
* @t: routing table
*
* Returns pointer to announce hook or NULL
*/
struct announce_hook *
proto_find_announce_hook(struct proto *p, struct rtable *t)
{
struct announce_hook *a;
for (a = p->ahooks; a; a = a->next)
if (a->table == t)
return a;
return NULL;
}
static void
proto_link_ahooks(struct proto *p)
{
struct announce_hook *h;
if (p->rt_notify)
for(h=p->ahooks; h; h=h->next)
add_tail(&h->table->hooks, &h->n);
}
static void
proto_unlink_ahooks(struct proto *p)
{
struct announce_hook *h;
if (p->rt_notify)
for(h=p->ahooks; h; h=h->next)
rem_node(&h->n);
}
static void
proto_free_ahooks(struct proto *p)
{
struct announce_hook *h, *hn;
for(h = p->ahooks; h; h = hn)
{
hn = h->next;
mb_free(h);
}
p->ahooks = NULL;
p->main_ahook = NULL;
}
/**
* proto_config_new - create a new protocol configuration
* @pr: protocol the configuration will belong to
* @class: SYM_PROTO or SYM_TEMPLATE
*
* Whenever the configuration file says that a new instance
* of a routing protocol should be created, the parser calls
* proto_config_new() to create a configuration entry for this
* instance (a structure staring with the &proto_config header
* containing all the generic items followed by protocol-specific
* ones). Also, the configuration entry gets added to the list
* of protocol instances kept in the configuration.
*
* The function is also used to create protocol templates (when class
* SYM_TEMPLATE is specified), the only difference is that templates
* are not added to the list of protocol instances and therefore not
* initialized during protos_commit()).
*/
void *
proto_config_new(struct protocol *pr, int class)
{
struct proto_config *c = cfg_allocz(pr->config_size);
if (class == SYM_PROTO)
add_tail(&new_config->protos, &c->n);
c->global = new_config;
c->protocol = pr;
c->name = pr->name;
c->preference = pr->preference;
c->class = class;
c->out_filter = FILTER_REJECT;
c->table = c->global->master_rtc;
c->debug = new_config->proto_default_debug;
c->mrtdump = new_config->proto_default_mrtdump;
return c;
}
/**
* proto_copy_config - copy a protocol configuration
* @dest: destination protocol configuration
* @src: source protocol configuration
*
* Whenever a new instance of a routing protocol is created from the
* template, proto_copy_config() is called to copy a content of
* the source protocol configuration to the new protocol configuration.
* Name, class and a node in protos list of @dest are kept intact.
* copy_config() protocol hook is used to copy protocol-specific data.
*/
void
proto_copy_config(struct proto_config *dest, struct proto_config *src)
{
node old_node;
int old_class;
char *old_name;
if (dest->protocol != src->protocol)
cf_error("Can't copy configuration from a different protocol type");
if (dest->protocol->copy_config == NULL)
cf_error("Inheriting configuration for %s is not supported", src->protocol->name);
DBG("Copying configuration from %s to %s\n", src->name, dest->name);
/*
* Copy struct proto_config here. Keep original node, class and name.
* protocol-specific config copy is handled by protocol copy_config() hook
*/
old_node = dest->n;
old_class = dest->class;
old_name = dest->name;
memcpy(dest, src, sizeof(struct proto_config));
dest->n = old_node;
dest->class = old_class;
dest->name = old_name;
dest->protocol->copy_config(dest, src);
}
/**
* protos_preconfig - pre-configuration processing
* @c: new configuration
*
* This function calls the preconfig() hooks of all routing
* protocols available to prepare them for reading of the new
* configuration.
*/
void
protos_preconfig(struct config *c)
{
struct protocol *p;
init_list(&c->protos);
DBG("Protocol preconfig:");
WALK_LIST(p, protocol_list)
{
DBG(" %s", p->name);
p->name_counter = 0;
if (p->preconfig)
p->preconfig(p, c);
}
DBG("\n");
}
/**
* protos_postconfig - post-configuration processing
* @c: new configuration
*
* This function calls the postconfig() hooks of all protocol
* instances specified in configuration @c. The hooks are not
* called for protocol templates.
*/
void
protos_postconfig(struct config *c)
{
struct proto_config *x;
struct protocol *p;
DBG("Protocol postconfig:");
WALK_LIST(x, c->protos)
{
DBG(" %s", x->name);
p = x->protocol;
if (p->postconfig)
p->postconfig(x);
}
DBG("\n");
}
extern struct protocol proto_unix_iface;
static struct proto *
proto_init(struct proto_config *c)
{
struct protocol *p = c->protocol;
struct proto *q = p->init(c);
q->proto_state = PS_DOWN;
q->core_state = FS_HUNGRY;
q->export_state = ES_DOWN;
q->last_state_change = now;
add_tail(&initial_proto_list, &q->n);
if (p == &proto_unix_iface)
initial_device_proto = q;
add_tail(&proto_list, &q->glob_node);
PD(q, "Initializing%s", q->disabled ? " [disabled]" : "");
return q;
}
int proto_reconfig_type; /* Hack to propagate type info to pipe reconfigure hook */
static int
proto_reconfigure(struct proto *p, struct proto_config *oc, struct proto_config *nc, int type)
{
/* If the protocol is DOWN, we just restart it */
if (p->proto_state == PS_DOWN)
return 0;
/* If there is a too big change in core attributes, ... */
if ((nc->protocol != oc->protocol) ||
(nc->disabled != p->disabled) ||
(nc->table->table != oc->table->table))
return 0;
p->debug = nc->debug;
p->mrtdump = nc->mrtdump;
proto_reconfig_type = type;
/* Execute protocol specific reconfigure hook */
if (! (p->proto->reconfigure && p->proto->reconfigure(p, nc)))
return 0;
DBG("\t%s: same\n", oc->name);
PD(p, "Reconfigured");
p->cf = nc;
p->name = nc->name;
p->preference = nc->preference;
/* Multitable protocols handle rest in their reconfigure hooks */
if (p->proto->multitable)
return 1;
/* Update filters and limits in the main announce hook
Note that this also resets limit state */
if (p->main_ahook)
{
struct announce_hook *ah = p->main_ahook;
ah->in_filter = nc->in_filter;
ah->out_filter = nc->out_filter;
ah->rx_limit = nc->rx_limit;
ah->in_limit = nc->in_limit;
ah->out_limit = nc->out_limit;
ah->in_keep_filtered = nc->in_keep_filtered;
proto_verify_limits(ah);
}
/* Update routes when filters changed. If the protocol in not UP,
it has no routes and we can ignore such changes */
if ((p->proto_state != PS_UP) || (type == RECONFIG_SOFT))
return 1;
int import_changed = ! filter_same(nc->in_filter, oc->in_filter);
int export_changed = ! filter_same(nc->out_filter, oc->out_filter);
/* We treat a change in preferences by reimporting routes */
if (nc->preference != oc->preference)
import_changed = 1;
if (import_changed || export_changed)
log(L_INFO "Reloading protocol %s", p->name);
/* If import filter changed, call reload hook */
if (import_changed && ! (p->reload_routes && p->reload_routes(p)))
{
/* Now, the protocol is reconfigured. But route reload failed
and we have to do regular protocol restart. */
log(L_INFO "Restarting protocol %s", p->name);
p->disabled = 1;
p->down_code = PDC_CF_RESTART;
proto_rethink_goal(p);
p->disabled = 0;
proto_rethink_goal(p);
return 1;
}
if (export_changed)
proto_request_feeding(p);
return 1;
}
/**
* protos_commit - commit new protocol configuration
* @new: new configuration
* @old: old configuration or %NULL if it's boot time config
* @force_reconfig: force restart of all protocols (used for example
* when the router ID changes)
* @type: type of reconfiguration (RECONFIG_SOFT or RECONFIG_HARD)
*
* Scan differences between @old and @new configuration and adjust all
* protocol instances to conform to the new configuration.
*
* When a protocol exists in the new configuration, but it doesn't in the
* original one, it's immediately started. When a collision with the other
* running protocol would arise, the new protocol will be temporarily stopped
* by the locking mechanism.
*
* When a protocol exists in the old configuration, but it doesn't in the
* new one, it's shut down and deleted after the shutdown completes.
*
* When a protocol exists in both configurations, the core decides
* whether it's possible to reconfigure it dynamically - it checks all
* the core properties of the protocol (changes in filters are ignored
* if type is RECONFIG_SOFT) and if they match, it asks the
* reconfigure() hook of the protocol to see if the protocol is able
* to switch to the new configuration. If it isn't possible, the
* protocol is shut down and a new instance is started with the new
* configuration after the shutdown is completed.
*/
void
protos_commit(struct config *new, struct config *old, int force_reconfig, int type)
{
struct proto_config *oc, *nc;
struct proto *p, *n;
struct symbol *sym;
DBG("protos_commit:\n");
if (old)
{
WALK_LIST(oc, old->protos)
{
p = oc->proto;
sym = cf_find_symbol(oc->name);
if (sym && sym->class == SYM_PROTO && !new->shutdown)
{
/* Found match, let's check if we can smoothly switch to new configuration */
/* No need to check description */
nc = sym->def;
nc->proto = p;
/* We will try to reconfigure protocol p */
if (! force_reconfig && proto_reconfigure(p, oc, nc, type))
continue;
/* Unsuccessful, we will restart it */
if (!p->disabled && !nc->disabled)
log(L_INFO "Restarting protocol %s", p->name);
else if (p->disabled && !nc->disabled)
log(L_INFO "Enabling protocol %s", p->name);
else if (!p->disabled && nc->disabled)
log(L_INFO "Disabling protocol %s", p->name);
p->down_code = nc->disabled ? PDC_CF_DISABLE : PDC_CF_RESTART;
p->cf_new = nc;
}
else if (!new->shutdown)
{
log(L_INFO "Removing protocol %s", p->name);
p->down_code = PDC_CF_REMOVE;
p->cf_new = NULL;
}
else /* global shutdown */
{
p->down_code = PDC_CMD_SHUTDOWN;
p->cf_new = NULL;
}
p->reconfiguring = 1;
config_add_obstacle(old);
proto_rethink_goal(p);
}
}
WALK_LIST(nc, new->protos)
if (!nc->proto)
{
if (old) /* Not a first-time configuration */
log(L_INFO "Adding protocol %s", nc->name);
proto_init(nc);
}
DBG("\tdone\n");
DBG("Protocol start\n");
/* Start device protocol first */
if (initial_device_proto)
{
proto_rethink_goal(initial_device_proto);
initial_device_proto = NULL;
}
/* Determine router ID for the first time - it has to be here and not in
global_commit() because it is postponed after start of device protocol */
if (!config->router_id)
{
config->router_id = if_choose_router_id(config->router_id_from, 0);
if (!config->router_id)
die("Cannot determine router ID, please configure it manually");
}
/* Start all other protocols */
WALK_LIST_DELSAFE(p, n, initial_proto_list)
proto_rethink_goal(p);
}
static void
proto_rethink_goal(struct proto *p)
{
struct protocol *q;
byte goal;
if (p->reconfiguring && p->core_state == FS_HUNGRY && p->proto_state == PS_DOWN)
{
struct proto_config *nc = p->cf_new;
DBG("%s has shut down for reconfiguration\n", p->name);
p->cf->proto = NULL;
config_del_obstacle(p->cf->global);
rem_node(&p->n);
rem_node(&p->glob_node);
mb_free(p);
if (!nc)
return;
p = proto_init(nc);
}
/* Determine what state we want to reach */
if (p->disabled || p->reconfiguring)
goal = PS_DOWN;
else
goal = PS_UP;
q = p->proto;
if (goal == PS_UP) /* Going up */
{
if (p->proto_state == PS_DOWN && p->core_state == FS_HUNGRY)
{
DBG("Kicking %s up\n", p->name);
PD(p, "Starting");
proto_init_instance(p);
proto_notify_state(p, (q->start ? q->start(p) : PS_UP));
}
}
else /* Going down */
{
if (p->proto_state == PS_START || p->proto_state == PS_UP)
{
DBG("Kicking %s down\n", p->name);
PD(p, "Shutting down");
proto_notify_state(p, (q->shutdown ? q->shutdown(p) : PS_DOWN));
}
}
}
/**
* DOC: Graceful restart recovery
*
* Graceful restart of a router is a process when the routing plane (e.g. BIRD)
* restarts but both the forwarding plane (e.g kernel routing table) and routing
* neighbors keep proper routes, and therefore uninterrupted packet forwarding
* is maintained.
*
* BIRD implements graceful restart recovery by deferring export of routes to
* protocols until routing tables are refilled with the expected content. After
* start, protocols generate routes as usual, but routes are not propagated to
* them, until protocols report that they generated all routes. After that,
* graceful restart recovery is finished and the export (and the initial feed)
* to protocols is enabled.
*
* When graceful restart recovery need is detected during initialization, then
* enabled protocols are marked with @gr_recovery flag before start. Such
* protocols then decide how to proceed with graceful restart, participation is
* voluntary. Protocols could lock the recovery by proto_graceful_restart_lock()
* (stored in @gr_lock flag), which means that they want to postpone the end of
* the recovery until they converge and then unlock it. They also could set
* @gr_wait before advancing to %PS_UP, which means that the core should defer
* route export to that protocol until the end of the recovery. This should be
* done by protocols that expect their neigbors to keep the proper routes
* (kernel table, BGP sessions with BGP graceful restart capability).
*
* The graceful restart recovery is finished when either all graceful restart
* locks are unlocked or when graceful restart wait timer fires.
*
*/
static void graceful_restart_done(struct timer *t);
/**
* graceful_restart_recovery - request initial graceful restart recovery
*
* Called by the platform initialization code if the need for recovery
* after graceful restart is detected during boot. Have to be called
* before protos_commit().
*/
void
graceful_restart_recovery(void)
{
graceful_restart_state = GRS_INIT;
}
/**
* graceful_restart_init - initialize graceful restart
*
* When graceful restart recovery was requested, the function starts an active
* phase of the recovery and initializes graceful restart wait timer. The
* function have to be called after protos_commit().
*/
void
graceful_restart_init(void)
{
if (!graceful_restart_state)
return;
log(L_INFO "Graceful restart started");
if (!graceful_restart_locks)
{
graceful_restart_done(NULL);
return;
}
graceful_restart_state = GRS_ACTIVE;
gr_wait_timer = tm_new(proto_pool);
gr_wait_timer->hook = graceful_restart_done;
tm_start(gr_wait_timer, config->gr_wait);
}
/**
* graceful_restart_done - finalize graceful restart
*
* When there are no locks on graceful restart, the functions finalizes the
* graceful restart recovery. Protocols postponing route export until the end of
* the recovery are awakened and the export to them is enabled. All other
* related state is cleared. The function is also called when the graceful
* restart wait timer fires (but there are still some locks).
*/
static void
graceful_restart_done(struct timer *t UNUSED)
{
struct proto *p;
node *n;
log(L_INFO "Graceful restart done");
graceful_restart_state = GRS_DONE;
WALK_LIST2(p, n, proto_list, glob_node)
{
if (!p->gr_recovery)
continue;
/* Resume postponed export of routes */
if ((p->proto_state == PS_UP) && p->gr_wait)
{
proto_want_export_up(p);
proto_log_state_change(p);
}
/* Cleanup */
p->gr_recovery = 0;
p->gr_wait = 0;
p->gr_lock = 0;
}
graceful_restart_locks = 0;
}
void
graceful_restart_show_status(void)
{
if (graceful_restart_state != GRS_ACTIVE)
return;
cli_msg(-24, "Graceful restart recovery in progress");
cli_msg(-24, " Waiting for %d protocols to recover", graceful_restart_locks);
cli_msg(-24, " Wait timer is %d/%d", tm_remains(gr_wait_timer), config->gr_wait);
}
/**
* proto_graceful_restart_lock - lock graceful restart by protocol
* @p: protocol instance
*
* This function allows a protocol to postpone the end of graceful restart
* recovery until it converges. The lock is removed when the protocol calls
* proto_graceful_restart_unlock() or when the protocol is stopped.
*
* The function have to be called during the initial phase of graceful restart
* recovery and only for protocols that are part of graceful restart (i.e. their
* @gr_recovery is set), which means it should be called from protocol start
* hooks.
*/
void
proto_graceful_restart_lock(struct proto *p)
{
ASSERT(graceful_restart_state == GRS_INIT);
ASSERT(p->gr_recovery);
if (p->gr_lock)
return;
p->gr_lock = 1;
graceful_restart_locks++;
}
/**
* proto_graceful_restart_unlock - unlock graceful restart by protocol
* @p: protocol instance
*
* This function unlocks a lock from proto_graceful_restart_lock(). It is also
* automatically called when the lock holding protocol went down.
*/
void
proto_graceful_restart_unlock(struct proto *p)
{
if (!p->gr_lock)
return;
p->gr_lock = 0;
graceful_restart_locks--;
if ((graceful_restart_state == GRS_ACTIVE) && !graceful_restart_locks)
tm_start(gr_wait_timer, 0);
}
/**
* protos_dump_all - dump status of all protocols
*
* This function dumps status of all existing protocol instances to the
* debug output. It involves printing of general status information
* such as protocol states, its position on the protocol lists
* and also calling of a dump() hook of the protocol to print
* the internals.
*/
void
protos_dump_all(void)
{
struct proto *p;
struct announce_hook *a;
debug("Protocols:\n");
WALK_LIST(p, active_proto_list)
{
debug(" protocol %s state %s/%s\n", p->name,
p_states[p->proto_state], c_states[p->core_state]);
for (a = p->ahooks; a; a = a->next)
{
debug("\tTABLE %s\n", a->table->name);
if (a->in_filter)
debug("\tInput filter: %s\n", filter_name(a->in_filter));
if (a->out_filter != FILTER_REJECT)
debug("\tOutput filter: %s\n", filter_name(a->out_filter));
}
if (p->disabled)
debug("\tDISABLED\n");
else if (p->proto->dump)
p->proto->dump(p);
}
WALK_LIST(p, inactive_proto_list)
debug(" inactive %s: state %s/%s\n", p->name, p_states[p->proto_state], c_states[p->core_state]);
WALK_LIST(p, initial_proto_list)
debug(" initial %s\n", p->name);
WALK_LIST(p, flush_proto_list)
debug(" flushing %s\n", p->name);
}
/**
* proto_build - make a single protocol available
* @p: the protocol
*
* After the platform specific initialization code uses protos_build()
* to add all the standard protocols, it should call proto_build() for
* all platform specific protocols to inform the core that they exist.
*/
void
proto_build(struct protocol *p)
{
add_tail(&protocol_list, &p->n);
if (p->attr_class)
{
ASSERT(!attr_class_to_protocol[p->attr_class]);
attr_class_to_protocol[p->attr_class] = p;
}
}
/* FIXME: convert this call to some protocol hook */
extern void bfd_init_all(void);
/**
* protos_build - build a protocol list
*
* This function is called during BIRD startup to insert
* all standard protocols to the global protocol list. Insertion
* of platform specific protocols (such as the kernel syncer)
* is in the domain of competence of the platform dependent
* startup code.
*/
void
protos_build(void)
{
init_list(&protocol_list);
init_list(&proto_list);
init_list(&active_proto_list);
init_list(&inactive_proto_list);
init_list(&initial_proto_list);
init_list(&flush_proto_list);
proto_build(&proto_device);
#ifdef CONFIG_RADV
proto_build(&proto_radv);
#endif
#ifdef CONFIG_RIP
proto_build(&proto_rip);
#endif
#ifdef CONFIG_STATIC
proto_build(&proto_static);
#endif
#ifdef CONFIG_OSPF
proto_build(&proto_ospf);
#endif
#ifdef CONFIG_PIPE
proto_build(&proto_pipe);
#endif
#ifdef CONFIG_BGP
proto_build(&proto_bgp);
#endif
#ifdef CONFIG_BFD
proto_build(&proto_bfd);
bfd_init_all();
#endif
proto_pool = rp_new(&root_pool, "Protocols");
proto_flush_event = ev_new(proto_pool);
proto_flush_event->hook = proto_flush_loop;
proto_shutdown_timer = tm_new(proto_pool);
proto_shutdown_timer->hook = proto_shutdown_loop;
}
static void
proto_feed_more(void *P)
{
struct proto *p = P;
if (p->export_state != ES_FEEDING)
return;
DBG("Feeding protocol %s continued\n", p->name);
if (rt_feed_baby(p))
{
DBG("Feeding protocol %s finished\n", p->name);
p->export_state = ES_READY;
proto_log_state_change(p);
if (p->feed_end)
p->feed_end(p);
}
else
{
p->attn->hook = proto_feed_more;
ev_schedule(p->attn); /* Will continue later... */
}
}
static void
proto_feed_initial(void *P)
{
struct proto *p = P;
if (p->export_state != ES_FEEDING)
return;
DBG("Feeding protocol %s\n", p->name);
if_feed_baby(p);
proto_feed_more(P);
}
static void
proto_schedule_feed(struct proto *p, int initial)
{
DBG("%s: Scheduling meal\n", p->name);
p->export_state = ES_FEEDING;
p->refeeding = !initial;
p->attn->hook = initial ? proto_feed_initial : proto_feed_more;
ev_schedule(p->attn);
if (p->feed_begin)
p->feed_begin(p, initial);
}
/*
* Flushing loop is responsible for flushing routes and protocols
* after they went down. It runs in proto_flush_event. At the start of
* one round, protocols waiting to flush are marked in
* proto_schedule_flush_loop(). At the end of the round (when routing
* table flush is complete), marked protocols are flushed and a next
* round may start.
*/
static int flush_loop_state; /* 1 -> running */
static void
proto_schedule_flush_loop(void)
{
struct proto *p;
struct announce_hook *h;
if (flush_loop_state)
return;
flush_loop_state = 1;
WALK_LIST(p, flush_proto_list)
{
p->flushing = 1;
for (h=p->ahooks; h; h=h->next)
rt_mark_for_prune(h->table);
}
ev_schedule(proto_flush_event);
}
static void
proto_flush_loop(void *unused UNUSED)
{
struct proto *p;
if (! rt_prune_loop())
{
/* Rtable pruning is not finished */
ev_schedule(proto_flush_event);
return;
}
rt_prune_sources();
again:
WALK_LIST(p, flush_proto_list)
if (p->flushing)
{
/* This will flush interfaces in the same manner
like rt_prune_all() flushes routes */
if (p->proto == &proto_unix_iface)
if_flush_ifaces(p);
DBG("Flushing protocol %s\n", p->name);
p->flushing = 0;
p->core_state = FS_HUNGRY;
proto_relink(p);
proto_log_state_change(p);
if (p->proto_state == PS_DOWN)
proto_fell_down(p);
goto again;
}
/* This round finished, perhaps there will be another one */
flush_loop_state = 0;
if (!EMPTY_LIST(flush_proto_list))
proto_schedule_flush_loop();
}
/* Temporary hack to propagate restart to BGP */
int proto_restart;
static void
proto_shutdown_loop(struct timer *t UNUSED)
{
struct proto *p, *p_next;
WALK_LIST_DELSAFE(p, p_next, active_proto_list)
if (p->down_sched)
{
proto_restart = (p->down_sched == PDS_RESTART);
p->disabled = 1;
proto_rethink_goal(p);
if (proto_restart)
{
p->disabled = 0;
proto_rethink_goal(p);
}
}
}
static inline void
proto_schedule_down(struct proto *p, byte restart, byte code)
{
/* Does not work for other states (even PS_START) */
ASSERT(p->proto_state == PS_UP);
/* Scheduled restart may change to shutdown, but not otherwise */
if (p->down_sched == PDS_DISABLE)
return;
p->down_sched = restart ? PDS_RESTART : PDS_DISABLE;
p->down_code = code;
tm_start_max(proto_shutdown_timer, restart ? 2 : 0);
}
/**
* proto_request_feeding - request feeding routes to the protocol
* @p: given protocol
*
* Sometimes it is needed to send again all routes to the
* protocol. This is called feeding and can be requested by this
* function. This would cause protocol export state transition
* to ES_FEEDING (during feeding) and when completed, it will
* switch back to ES_READY. This function can be called even
* when feeding is already running, in that case it is restarted.
*/
void
proto_request_feeding(struct proto *p)
{
ASSERT(p->proto_state == PS_UP);
/* Do nothing if we are still waiting for feeding */
if (p->export_state == ES_DOWN)
return;
/* If we are already feeding, we want to restart it */
if (p->export_state == ES_FEEDING)
{
/* Unless feeding is in initial state */
if (p->attn->hook == proto_feed_initial)
return;
rt_feed_baby_abort(p);
}
/* FIXME: This should be changed for better support of multitable protos */
struct announce_hook *ah;
for (ah = p->ahooks; ah; ah = ah->next)
proto_reset_limit(ah->out_limit);
/* Hack: reset exp_routes during refeed, and do not decrease it later */
p->stats.exp_routes = 0;
proto_schedule_feed(p, 0);
proto_log_state_change(p);
}
static const char *
proto_limit_name(struct proto_limit *l)
{
const char *actions[] = {
[PLA_WARN] = "warn",
[PLA_BLOCK] = "block",
[PLA_RESTART] = "restart",
[PLA_DISABLE] = "disable",
};
return actions[l->action];
}
/**
* proto_notify_limit: notify about limit hit and take appropriate action
* @ah: announce hook
* @l: limit being hit
* @dir: limit direction (PLD_*)
* @rt_count: the number of routes
*
* The function is called by the route processing core when limit @l
* is breached. It activates the limit and tooks appropriate action
* according to @l->action.
*/
void
proto_notify_limit(struct announce_hook *ah, struct proto_limit *l, int dir, u32 rt_count)
{
const char *dir_name[PLD_MAX] = { "receive", "import" , "export" };
const byte dir_down[PLD_MAX] = { PDC_RX_LIMIT_HIT, PDC_IN_LIMIT_HIT, PDC_OUT_LIMIT_HIT };
struct proto *p = ah->proto;
if (l->state == PLS_BLOCKED)
return;
/* For warning action, we want the log message every time we hit the limit */
if (!l->state || ((l->action == PLA_WARN) && (rt_count == l->limit)))
log(L_WARN "Protocol %s hits route %s limit (%d), action: %s",
p->name, dir_name[dir], l->limit, proto_limit_name(l));
switch (l->action)
{
case PLA_WARN:
l->state = PLS_ACTIVE;
break;
case PLA_BLOCK:
l->state = PLS_BLOCKED;
break;
case PLA_RESTART:
case PLA_DISABLE:
l->state = PLS_BLOCKED;
if (p->proto_state == PS_UP)
proto_schedule_down(p, l->action == PLA_RESTART, dir_down[dir]);
break;
}
}
void
proto_verify_limits(struct announce_hook *ah)
{
struct proto_limit *l;
struct proto_stats *stats = ah->stats;
u32 all_routes = stats->imp_routes + stats->filt_routes;
l = ah->rx_limit;
if (l && (all_routes > l->limit))
proto_notify_limit(ah, l, PLD_RX, all_routes);
l = ah->in_limit;
if (l && (stats->imp_routes > l->limit))
proto_notify_limit(ah, l, PLD_IN, stats->imp_routes);
l = ah->out_limit;
if (l && (stats->exp_routes > l->limit))
proto_notify_limit(ah, l, PLD_OUT, stats->exp_routes);
}
static void
proto_want_core_up(struct proto *p)
{
ASSERT(p->core_state == FS_HUNGRY);
if (!p->proto->multitable)
{
p->main_source = rt_get_source(p, 0);
rt_lock_source(p->main_source);
/* Connect protocol to routing table */
p->main_ahook = proto_add_announce_hook(p, p->table, &p->stats);
p->main_ahook->in_filter = p->cf->in_filter;
p->main_ahook->out_filter = p->cf->out_filter;
p->main_ahook->rx_limit = p->cf->rx_limit;
p->main_ahook->in_limit = p->cf->in_limit;
p->main_ahook->out_limit = p->cf->out_limit;
p->main_ahook->in_keep_filtered = p->cf->in_keep_filtered;
proto_reset_limit(p->main_ahook->rx_limit);
proto_reset_limit(p->main_ahook->in_limit);
proto_reset_limit(p->main_ahook->out_limit);
}
p->core_state = FS_HAPPY;
proto_relink(p);
}
static void
proto_want_export_up(struct proto *p)
{
ASSERT(p->core_state == FS_HAPPY);
ASSERT(p->export_state == ES_DOWN);
proto_link_ahooks(p);
proto_schedule_feed(p, 1); /* Sets ES_FEEDING */
}
static void
proto_want_export_down(struct proto *p)
{
ASSERT(p->export_state != ES_DOWN);
/* Need to abort feeding */
if (p->export_state == ES_FEEDING)
rt_feed_baby_abort(p);
p->export_state = ES_DOWN;
proto_unlink_ahooks(p);
}
static void
proto_want_core_down(struct proto *p)
{
ASSERT(p->core_state == FS_HAPPY);
ASSERT(p->export_state == ES_DOWN);
p->core_state = FS_FLUSHING;
proto_relink(p);
proto_schedule_flush_loop();
if (!p->proto->multitable)
{
rt_unlock_source(p->main_source);
p->main_source = NULL;
}
}
static void
proto_falling_down(struct proto *p)
{
p->gr_recovery = 0;
p->gr_wait = 0;
if (p->gr_lock)
proto_graceful_restart_unlock(p);
}
static void
proto_fell_down(struct proto *p)
{
DBG("Protocol %s down\n", p->name);
u32 all_routes = p->stats.imp_routes + p->stats.filt_routes;
if (all_routes != 0)
log(L_ERR "Protocol %s is down but still has %d routes", p->name, all_routes);
bzero(&p->stats, sizeof(struct proto_stats));
proto_free_ahooks(p);
if (! p->proto->multitable)
rt_unlock_table(p->table);
if (p->proto->cleanup)
p->proto->cleanup(p);
proto_rethink_goal(p);
}
/**
* proto_notify_state - notify core about protocol state change
* @p: protocol the state of which has changed
* @ps: the new status
*
* Whenever a state of a protocol changes due to some event internal
* to the protocol (i.e., not inside a start() or shutdown() hook),
* it should immediately notify the core about the change by calling
* proto_notify_state() which will write the new state to the &proto
* structure and take all the actions necessary to adapt to the new
* state. State change to PS_DOWN immediately frees resources of protocol
* and might execute start callback of protocol; therefore,
* it should be used at tail positions of protocol callbacks.
*/
void
proto_notify_state(struct proto *p, unsigned ps)
{
unsigned ops = p->proto_state;
unsigned cs = p->core_state;
unsigned es = p->export_state;
DBG("%s reporting state transition %s/%s -> */%s\n", p->name, c_states[cs], p_states[ops], p_states[ps]);
if (ops == ps)
return;
p->proto_state = ps;
p->last_state_change = now;
switch (ps)
{
case PS_START:
ASSERT(ops == PS_DOWN || ops == PS_UP);
ASSERT(cs == FS_HUNGRY || cs == FS_HAPPY);
if (es != ES_DOWN)
proto_want_export_down(p);
break;
case PS_UP:
ASSERT(ops == PS_DOWN || ops == PS_START);
ASSERT(cs == FS_HUNGRY || cs == FS_HAPPY);
ASSERT(es == ES_DOWN);
if (cs == FS_HUNGRY)
proto_want_core_up(p);
if (!p->gr_wait)
proto_want_export_up(p);
break;
case PS_STOP:
ASSERT(ops == PS_START || ops == PS_UP);
p->down_sched = 0;
if (es != ES_DOWN)
proto_want_export_down(p);
if (cs == FS_HAPPY)
proto_want_core_down(p);
proto_falling_down(p);
break;
case PS_DOWN:
p->down_code = 0;
p->down_sched = 0;
if (es != ES_DOWN)
proto_want_export_down(p);
if (cs == FS_HAPPY)
proto_want_core_down(p);
if (ops != PS_STOP)
proto_falling_down(p);
neigh_prune(); // FIXME convert neighbors to resource?
rfree(p->pool);
p->pool = NULL;
if (cs == FS_HUNGRY) /* Shutdown finished */
{
proto_log_state_change(p);
proto_fell_down(p);
return; /* The protocol might have ceased to exist */
}
break;
default:
bug("%s: Invalid state %d", p->name, ps);
}
proto_log_state_change(p);
}
/*
* CLI Commands
*/
static char *
proto_state_name(struct proto *p)
{
#define P(x,y) ((x << 4) | y)
switch (P(p->proto_state, p->core_state))
{
case P(PS_DOWN, FS_HUNGRY): return "down";
case P(PS_START, FS_HUNGRY):
case P(PS_START, FS_HAPPY): return "start";
case P(PS_UP, FS_HAPPY):
switch (p->export_state)
{
case ES_DOWN: return "wait";
case ES_FEEDING: return "feed";
case ES_READY: return "up";
default: return "???";
}
case P(PS_STOP, FS_HUNGRY):
case P(PS_STOP, FS_FLUSHING): return "stop";
case P(PS_DOWN, FS_FLUSHING): return "flush";
default: return "???";
}
#undef P
}
static void
proto_show_stats(struct proto_stats *s, int in_keep_filtered)
{
if (in_keep_filtered)
cli_msg(-1006, " Routes: %u imported, %u filtered, %u exported, %u preferred",
s->imp_routes, s->filt_routes, s->exp_routes, s->pref_routes);
else
cli_msg(-1006, " Routes: %u imported, %u exported, %u preferred",
s->imp_routes, s->exp_routes, s->pref_routes);
cli_msg(-1006, " Route change stats: received rejected filtered ignored accepted");
cli_msg(-1006, " Import updates: %10u %10u %10u %10u %10u",
s->imp_updates_received, s->imp_updates_invalid,
s->imp_updates_filtered, s->imp_updates_ignored,
s->imp_updates_accepted);
cli_msg(-1006, " Import withdraws: %10u %10u --- %10u %10u",
s->imp_withdraws_received, s->imp_withdraws_invalid,
s->imp_withdraws_ignored, s->imp_withdraws_accepted);
cli_msg(-1006, " Export updates: %10u %10u %10u --- %10u",
s->exp_updates_received, s->exp_updates_rejected,
s->exp_updates_filtered, s->exp_updates_accepted);
cli_msg(-1006, " Export withdraws: %10u --- --- --- %10u",
s->exp_withdraws_received, s->exp_withdraws_accepted);
}
void
proto_show_limit(struct proto_limit *l, const char *dsc)
{
if (!l)
return;
cli_msg(-1006, " %-16s%d%s", dsc, l->limit, l->state ? " [HIT]" : "");
cli_msg(-1006, " Action: %s", proto_limit_name(l));
}
void
proto_show_basic_info(struct proto *p)
{
// cli_msg(-1006, " Table: %s", p->table->name);
cli_msg(-1006, " Preference: %d", p->preference);
cli_msg(-1006, " Input filter: %s", filter_name(p->cf->in_filter));
cli_msg(-1006, " Output filter: %s", filter_name(p->cf->out_filter));
if (graceful_restart_state == GRS_ACTIVE)
cli_msg(-1006, " GR recovery: %s%s",
p->gr_lock ? " pending" : "",
p->gr_wait ? " waiting" : "");
proto_show_limit(p->cf->rx_limit, "Receive limit:");
proto_show_limit(p->cf->in_limit, "Import limit:");
proto_show_limit(p->cf->out_limit, "Export limit:");
if (p->proto_state != PS_DOWN)
proto_show_stats(&p->stats, p->cf->in_keep_filtered);
}
void
proto_cmd_show(struct proto *p, uint verbose, int cnt)
{
byte buf[256], tbuf[TM_DATETIME_BUFFER_SIZE];
/* First protocol - show header */
if (!cnt)
cli_msg(-2002, "name proto table state since info");
buf[0] = 0;
if (p->proto->get_status)
p->proto->get_status(p, buf);
tm_format_datetime(tbuf, &config->tf_proto, p->last_state_change);
cli_msg(-1002, "%-8s %-8s %-8s %-5s %-10s %s",
p->name,
p->proto->name,
p->table->name,
proto_state_name(p),
tbuf,
buf);
if (verbose)
{
if (p->cf->dsc)
cli_msg(-1006, " Description: %s", p->cf->dsc);
if (p->cf->router_id)
cli_msg(-1006, " Router ID: %R", p->cf->router_id);
if (p->proto->show_proto_info)
p->proto->show_proto_info(p);
else
proto_show_basic_info(p);
cli_msg(-1006, "");
}
}
void
proto_cmd_disable(struct proto *p, uint arg UNUSED, int cnt UNUSED)
{
if (p->disabled)
{
cli_msg(-8, "%s: already disabled", p->name);
return;
}
log(L_INFO "Disabling protocol %s", p->name);
p->disabled = 1;
p->down_code = PDC_CMD_DISABLE;
proto_rethink_goal(p);
cli_msg(-9, "%s: disabled", p->name);
}
void
proto_cmd_enable(struct proto *p, uint arg UNUSED, int cnt UNUSED)
{
if (!p->disabled)
{
cli_msg(-10, "%s: already enabled", p->name);
return;
}
log(L_INFO "Enabling protocol %s", p->name);
p->disabled = 0;
proto_rethink_goal(p);
cli_msg(-11, "%s: enabled", p->name);
}
void
proto_cmd_restart(struct proto *p, uint arg UNUSED, int cnt UNUSED)
{
if (p->disabled)
{
cli_msg(-8, "%s: already disabled", p->name);
return;
}
log(L_INFO "Restarting protocol %s", p->name);
p->disabled = 1;
p->down_code = PDC_CMD_RESTART;
proto_rethink_goal(p);
p->disabled = 0;
proto_rethink_goal(p);
cli_msg(-12, "%s: restarted", p->name);
}
void
proto_cmd_reload(struct proto *p, uint dir, int cnt UNUSED)
{
if (p->disabled)
{
cli_msg(-8, "%s: already disabled", p->name);
return;
}
/* If the protocol in not UP, it has no routes */
if (p->proto_state != PS_UP)
return;
log(L_INFO "Reloading protocol %s", p->name);
/* re-importing routes */
if (dir != CMD_RELOAD_OUT)
{
if (! (p->reload_routes && p->reload_routes(p)))
{
cli_msg(-8006, "%s: reload failed", p->name);
return;
}
/*
* Should be done before reload_routes() hook?
* Perhaps, but these hooks work asynchronously.
*/
if (!p->proto->multitable)
{
proto_reset_limit(p->main_ahook->rx_limit);
proto_reset_limit(p->main_ahook->in_limit);
}
}
/* re-exporting routes */
if (dir != CMD_RELOAD_IN)
proto_request_feeding(p);
cli_msg(-15, "%s: reloading", p->name);
}
void
proto_cmd_debug(struct proto *p, uint mask, int cnt UNUSED)
{
p->debug = mask;
}
void
proto_cmd_mrtdump(struct proto *p, uint mask, int cnt UNUSED)
{
p->mrtdump = mask;
}
static void
proto_apply_cmd_symbol(struct symbol *s, void (* cmd)(struct proto *, uint, int), uint arg)
{
if (s->class != SYM_PROTO)
{
cli_msg(9002, "%s is not a protocol", s->name);
return;
}
cmd(((struct proto_config *)s->def)->proto, arg, 0);
cli_msg(0, "");
}
static void
proto_apply_cmd_patt(char *patt, void (* cmd)(struct proto *, uint, int), uint arg)
{
int cnt = 0;
node *nn;
WALK_LIST(nn, proto_list)
{
struct proto *p = SKIP_BACK(struct proto, glob_node, nn);
if (!patt || patmatch(patt, p->name))
cmd(p, arg, cnt++);
}
if (!cnt)
cli_msg(8003, "No protocols match");
else
cli_msg(0, "");
}
void
proto_apply_cmd(struct proto_spec ps, void (* cmd)(struct proto *, uint, int),
int restricted, uint arg)
{
if (restricted && cli_access_restricted())
return;
if (ps.patt)
proto_apply_cmd_patt(ps.ptr, cmd, arg);
else
proto_apply_cmd_symbol(ps.ptr, cmd, arg);
}
struct proto *
proto_get_named(struct symbol *sym, struct protocol *pr)
{
struct proto *p, *q;
if (sym)
{
if (sym->class != SYM_PROTO)
cf_error("%s: Not a protocol", sym->name);
p = ((struct proto_config *)sym->def)->proto;
if (!p || p->proto != pr)
cf_error("%s: Not a %s protocol", sym->name, pr->name);
}
else
{
p = NULL;
WALK_LIST(q, active_proto_list)
if (q->proto == pr)
{
if (p)
cf_error("There are multiple %s protocols running", pr->name);
p = q;
}
if (!p)
cf_error("There is no %s protocol running", pr->name);
}
return p;
}