diff --git a/doc/bird.sgml b/doc/bird.sgml
index b4d9ea4e..44fef1c5 100644
--- a/doc/bird.sgml
+++ b/doc/bird.sgml
@@ -2220,13 +2220,16 @@ using the following configuration parameters:
immediately shut down. Note that this option cannot be used with
multihop BGP. Default: enabled for direct BGP, disabled otherwise.
- bfd switch bfd switch |graceful [ section for details. Default: disabled.
+ failure. When a neighbor failure is detected, the BGP session is
+ restarted. Optionally, it can be configured (by ]
+ section for details. Default: disabled.
ttl security
Use GTSM ( - the generalized TTL security mechanism). GTSM
@@ -2348,6 +2351,25 @@ using the following configuration parameters:
re-establish after a restart before deleting stale routes. Default:
120 seconds.
+ long lived graceful restart
+ The long-lived graceful restart is an extension of the traditional
+ [, where stale
+ routes are kept even after the ][ expires for additional long-lived stale time, but
+ they are marked with the LLGR_STALE community, depreferenced, and
+ withdrawn from routers not supporting LLGR. Like traditional BGP
+ graceful restart, it has three states: disabled, aware (receiving-only),
+ and enabled. Note that long-lived graceful restart requires at least
+ aware level of traditional BGP graceful restart. Default: aware, unless
+ graceful restart is disabled.
+
+ ]long lived stale time
+ The long-lived stale time is announced in the BGP long-lived graceful
+ restart capability and specifies how long the neighbor would keep stale
+ routes depreferenced during long-lived graceful restart until either the
+ session is re-stablished and synchronized or the stale time expires and
+ routes are removed. Default: 3600 seconds.
+
interpret communities
demands that BGP speaker should process well-known
communities like no-export (65535, 65281) or no-advertise (65535,
@@ -2607,6 +2629,19 @@ be used in explicit configuration.
configure restarting role per AFI/SAFI pair by this channel option.
The option is ignored if graceful restart is disabled by protocol-wide
option. Default: off in aware mode, on in full mode.
+
+ long lived graceful restart
+ BGP long-lived graceful restart is configured mainly by protocol-wide
+ [, but the
+ restarting role can be set per AFI/SAFI pair by this channel option.
+ The option is ignored if long-lived graceful restart is disabled by
+ protocol-wide option. Default: off in aware mode, on in full mode.
+
+ ]long lived stale time
+ Like previous graceful restart channel options, this option allows to
+ set [
+ per AFI/SAFI pair instead of per protocol. Default: set by protocol-wide
+ option.
]Attributes
@@ -2761,7 +2796,6 @@ interfaces to be defined for them to work with.
so the default time is set to a large value.
interface
-
By default, the Device protocol handles all interfaces without any
configuration. Interface definitions allow to specify optional
parameters for specific interfaces. See [flags & REF_FILTERED); }
@@ -297,6 +299,7 @@ int rt_examine(rtable *t, net_addr *a, struct proto *p, struct filter *filter);
rte *rt_export_merged(struct channel *c, net *net, rte **rt_free, linpool *pool, int silent);
void rt_refresh_begin(rtable *t, struct channel *c);
void rt_refresh_end(rtable *t, struct channel *c);
+void rt_modify_stale(rtable *t, struct channel *c);
void rt_schedule_prune(rtable *t);
void rte_dump(rte *);
void rte_free(rte *);
diff --git a/nest/rt-table.c b/nest/rt-table.c
index 9dcbda05..036b34c4 100644
--- a/nest/rt-table.c
+++ b/nest/rt-table.c
@@ -1437,6 +1437,28 @@ rte_discard(rte *old) /* Non-filtered route deletion, used during garbage collec
rte_update_unlock();
}
+/* Modify existing route by protocol hook, used for long-lived graceful restart */
+static inline void
+rte_modify(rte *old)
+{
+ rte_update_lock();
+
+ rte *new = old->sender->proto->rte_modify(old, rte_update_pool);
+ if (new != old)
+ {
+ if (new)
+ {
+ if (!rta_is_cached(new->attrs))
+ new->attrs = rta_lookup(new->attrs);
+ new->flags = (old->flags & ~REF_MODIFY) | REF_COW;
+ }
+
+ rte_recalculate(old->sender, old->net, new, old->attrs->src);
+ }
+
+ rte_update_unlock();
+}
+
/* Check rtable for best route to given net whether it would be exported do p */
int
rt_examine(rtable *t, net_addr *a, struct proto *p, struct filter *filter)
@@ -1521,6 +1543,26 @@ rt_refresh_end(rtable *t, struct channel *c)
rt_schedule_prune(t);
}
+void
+rt_modify_stale(rtable *t, struct channel *c)
+{
+ int prune = 0;
+
+ FIB_WALK(&t->fib, net, n)
+ {
+ rte *e;
+ for (e = n->routes; e; e = e->next)
+ if ((e->sender == c) && (e->flags & REF_STALE) && !(e->flags & REF_FILTERED))
+ {
+ e->flags |= REF_MODIFY;
+ prune = 1;
+ }
+ }
+ FIB_WALK_END;
+
+ if (prune)
+ rt_schedule_prune(t);
+}
/**
* rte_dump - dump a route
@@ -1712,6 +1754,7 @@ again:
rescan:
for (e=n->routes; e; e=e->next)
+ {
if (e->sender->flush_active || (e->flags & REF_DISCARD))
{
if (limit <= 0)
@@ -1727,6 +1770,22 @@ again:
goto rescan;
}
+ if (e->flags & REF_MODIFY)
+ {
+ if (limit <= 0)
+ {
+ FIB_ITERATE_PUT(fit);
+ ev_schedule(tab->rt_event);
+ return;
+ }
+
+ rte_modify(e);
+ limit--;
+
+ goto rescan;
+ }
+ }
+
if (!n->routes) /* Orphaned FIB entry */
{
FIB_ITERATE_PUT(fit);
diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c
index 6580db57..dc267fdb 100644
--- a/proto/bgp/attrs.c
+++ b/proto/bgp/attrs.c
@@ -1413,6 +1413,10 @@ bgp_import_control(struct proto *P, rte **new, struct linpool *pool UNUSED)
/* Do not export outside of AS (or confederation) */
if (!p->is_interior && int_set_contains(d, BGP_COMM_NO_EXPORT))
return -1;
+
+ /* Do not export LLGR_STALE routes to LLGR-ignorant peers */
+ if (!p->conn->remote_caps->llgr_aware && int_set_contains(d, BGP_COMM_LLGR_STALE))
+ return -1;
}
return 0;
@@ -1580,6 +1584,19 @@ rte_resolvable(rte *rt)
return rt->attrs->dest == RTD_UNICAST;
}
+static inline int
+rte_stale(rte *r)
+{
+ if (r->u.bgp.stale < 0)
+ {
+ /* If staleness is unknown, compute and cache it */
+ eattr *a = ea_find(r->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_COMMUNITY));
+ r->u.bgp.stale = a && int_set_contains(a->u.ptr, BGP_COMM_LLGR_STALE);
+ }
+
+ return r->u.bgp.stale;
+}
+
int
bgp_rte_better(rte *new, rte *old)
{
@@ -1604,7 +1621,15 @@ bgp_rte_better(rte *new, rte *old)
if (n < o)
return 0;
- /* Start with local preferences */
+ /* LLGR draft - depreference stale routes */
+ n = rte_stale(new);
+ o = rte_stale(old);
+ if (n > o)
+ return 0;
+ if (n < o)
+ return 1;
+
+ /* Start with local preferences */
x = ea_find(new->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_LOCAL_PREF));
y = ea_find(old->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_LOCAL_PREF));
n = x ? x->u.data : new_bgp->cf->default_local_pref;
@@ -1725,6 +1750,10 @@ bgp_rte_mergable(rte *pri, rte *sec)
if (!rte_resolvable(sec))
return 0;
+ /* LLGR draft - depreference stale routes */
+ if (rte_stale(pri) != rte_stale(sec))
+ return 0;
+
/* Start with local preferences */
x = ea_find(pri->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_LOCAL_PREF));
y = ea_find(sec->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_LOCAL_PREF));
@@ -1926,6 +1955,27 @@ bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best)
return old_is_group_best;
}
+struct rte *
+bgp_rte_modify_stale(struct rte *r, struct linpool *pool)
+{
+ eattr *a = ea_find(r->attrs->eattrs, EA_CODE(PROTOCOL_BGP, BA_COMMUNITY));
+ struct adata *ad = a ? a->u.ptr : NULL;
+ uint flags = a ? a->flags : BAF_PARTIAL;
+
+ if (ad && int_set_contains(ad, BGP_COMM_NO_LLGR))
+ return NULL;
+
+ if (ad && int_set_contains(ad, BGP_COMM_LLGR_STALE))
+ return r;
+
+ r = rte_cow_rta(r, pool);
+ bgp_set_attr_ptr(&(r->attrs->eattrs), pool, BA_COMMUNITY, flags,
+ int_set_add(pool, ad, BGP_COMM_LLGR_STALE));
+ r->u.bgp.stale = 1;
+
+ return r;
+}
+
/*
* Reconstruct AS_PATH and AGGREGATOR according to RFC 6793 4.2.3
@@ -2011,6 +2061,9 @@ bgp_get_route_info(rte *e, byte *buf)
if (e->u.bgp.suppressed)
buf += bsprintf(buf, "-");
+ if (rte_stale(e))
+ buf += bsprintf(buf, "s");
+
if (e->attrs->hostentry)
{
if (!rte_resolvable(e))
diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c
index ced83c5c..6dea88c8 100644
--- a/proto/bgp/bgp.c
+++ b/proto/bgp/bgp.c
@@ -513,8 +513,8 @@ bgp_conn_enter_established_state(struct bgp_conn *conn)
p->route_refresh = peer->route_refresh;
p->enhanced_refresh = local->enhanced_refresh && peer->enhanced_refresh;
- /* Whether we may handle possible GR of peer (it has some AF GR-able) */
- p->gr_ready = 0; /* Updated later */
+ /* Whether we may handle possible GR/LLGR of peer (it has some AF GR-able) */
+ p->gr_ready = p->llgr_ready = 0; /* Updated later */
/* Whether peer is ready to handle our GR recovery */
int peer_gr_ready = peer->gr_aware && !(peer->gr_flags & BGP_GRF_RESTART);
@@ -547,8 +547,15 @@ bgp_conn_enter_established_state(struct bgp_conn *conn)
c->load_state = BFS_NONE;
/* Channels where peer may do GR */
- c->gr_ready = active && local->gr_aware && rem->gr_able;
+ uint gr_ready = active && local->gr_aware && rem->gr_able;
+ uint llgr_ready = active && local->llgr_aware && rem->llgr_able;
+
+ c->gr_ready = gr_ready || llgr_ready;
p->gr_ready = p->gr_ready || c->gr_ready;
+ p->llgr_ready = p->llgr_ready || llgr_ready;
+
+ /* Remember last LLGR stale time */
+ c->stale_time = local->llgr_aware ? rem->llgr_time : 0;
/* Channels not able to recover gracefully */
if (p->p.gr_recovery && (!active || !peer_gr_ready))
@@ -558,8 +565,14 @@ bgp_conn_enter_established_state(struct bgp_conn *conn)
if (p->p.gr_recovery && loc->gr_able && peer_gr_ready)
c->c.gr_wait = 1;
- /* Channels where peer is not able to recover gracefully */
- if (c->gr_active && ! (c->gr_ready && (rem->gr_af_flags & BGP_GRF_FORWARDING)))
+ /* Channels where regular graceful restart failed */
+ if ((c->gr_active == BGP_GRS_ACTIVE) &&
+ !(active && rem->gr_able && (rem->gr_af_flags & BGP_GRF_FORWARDING)))
+ bgp_graceful_restart_done(c);
+
+ /* Channels where regular long-lived restart failed */
+ if ((c->gr_active == BGP_GRS_LLGR) &&
+ !(active && rem->llgr_able && (rem->gr_af_flags & BGP_LLGRF_FORWARDING)))
bgp_graceful_restart_done(c);
/* GR capability implies that neighbor will send End-of-RIB */
@@ -669,12 +682,25 @@ bgp_handle_graceful_restart(struct bgp_proto *p)
if (c->gr_ready)
{
- if (c->gr_active)
- rt_refresh_end(c->c.table, &c->c);
-
- c->gr_active = 1;
p->gr_active_num++;
- rt_refresh_begin(c->c.table, &c->c);
+
+ switch (c->gr_active)
+ {
+ case BGP_GRS_NONE:
+ c->gr_active = BGP_GRS_ACTIVE;
+ rt_refresh_begin(c->c.table, &c->c);
+ break;
+
+ case BGP_GRS_ACTIVE:
+ rt_refresh_end(c->c.table, &c->c);
+ rt_refresh_begin(c->c.table, &c->c);
+ break;
+
+ case BGP_GRS_LLGR:
+ rt_refresh_begin(c->c.table, &c->c);
+ rt_modify_stale(c->c.table, &c->c);
+ break;
+ }
}
else
{
@@ -695,7 +721,7 @@ bgp_handle_graceful_restart(struct bgp_proto *p)
ASSERT(p->gr_active_num > 0);
proto_notify_state(&p->p, PS_START);
- bgp_start_timer(p->gr_timer, p->conn->remote_caps->gr_time);
+ tm_start(p->gr_timer, p->conn->remote_caps->gr_time S);
}
/**
@@ -720,6 +746,7 @@ bgp_graceful_restart_done(struct bgp_channel *c)
if (!p->gr_active_num)
BGP_TRACE(D_EVENTS, "Neighbor graceful restart done");
+ tm_stop(c->stale_timer);
rt_refresh_end(c->c.table, &c->c);
}
@@ -738,7 +765,46 @@ bgp_graceful_restart_timeout(timer *t)
struct bgp_proto *p = t->data;
BGP_TRACE(D_EVENTS, "Neighbor graceful restart timeout");
- bgp_stop(p, 0, NULL, 0);
+
+ if (p->llgr_ready)
+ {
+ struct bgp_channel *c;
+ WALK_LIST(c, p->p.channels)
+ {
+ /* Channel is not in GR and is already flushed */
+ if (!c->gr_active)
+ continue;
+
+ /* Channel is already in LLGR from past restart */
+ if (c->gr_active == BGP_GRS_LLGR)
+ continue;
+
+ /* Channel is in GR, but does not support LLGR -> stop GR */
+ if (!c->stale_time)
+ {
+ bgp_graceful_restart_done(c);
+ continue;
+ }
+
+ /* Channel is in GR, and supports LLGR -> start LLGR */
+ c->gr_active = BGP_GRS_LLGR;
+ tm_start(c->stale_timer, c->stale_time S);
+ rt_modify_stale(c->c.table, &c->c);
+ }
+ }
+ else
+ bgp_stop(p, 0, NULL, 0);
+}
+
+static void
+bgp_long_lived_stale_timeout(timer *t)
+{
+ struct bgp_channel *c = t->data;
+ struct bgp_proto *p = (void *) c->c.proto;
+
+ BGP_TRACE(D_EVENTS, "Long-lived stale timeout");
+
+ bgp_graceful_restart_done(c);
}
@@ -873,6 +939,12 @@ bgp_hold_timeout(timer *t)
if (sk_rx_ready(conn->sk) > 0)
bgp_start_timer(conn->hold_timer, 10);
+ else if ((conn->state == BS_ESTABLISHED) && p->llgr_ready)
+ {
+ BGP_TRACE(D_EVENTS, "Hold timer expired");
+ bgp_handle_graceful_restart(p);
+ bgp_conn_enter_idle_state(conn);
+ }
else
bgp_error(conn, 4, 0, NULL, 0);
}
@@ -1172,9 +1244,26 @@ bgp_bfd_notify(struct bfd_request *req)
{
BGP_TRACE(D_EVENTS, "BFD session down");
bgp_store_error(p, NULL, BE_MISC, BEM_BFD_DOWN);
- if (ps == PS_UP)
- bgp_update_startup_delay(p);
- bgp_stop(p, 0, NULL, 0);
+
+ if (p->cf->bfd == BGP_BFD_GRACEFUL)
+ {
+ /* Trigger graceful restart */
+ if (p->conn && (p->conn->state == BS_ESTABLISHED) && p->gr_ready)
+ bgp_handle_graceful_restart(p);
+
+ if (p->incoming_conn.state > BS_IDLE)
+ bgp_conn_enter_idle_state(&p->incoming_conn);
+
+ if (p->outgoing_conn.state > BS_IDLE)
+ bgp_conn_enter_idle_state(&p->outgoing_conn);
+ }
+ else
+ {
+ /* Trigger session down */
+ if (ps == PS_UP)
+ bgp_update_startup_delay(p);
+ bgp_stop(p, 0, NULL, 0);
+ }
}
}
@@ -1447,6 +1536,7 @@ bgp_init(struct proto_config *CF)
P->rte_better = bgp_rte_better;
P->rte_mergable = bgp_rte_mergable;
P->rte_recalculate = cf->deterministic_med ? bgp_rte_recalculate : NULL;
+ P->rte_modify = bgp_rte_modify_stale;
p->cf = cf;
p->local_as = cf->local_as;
@@ -1503,6 +1593,8 @@ bgp_channel_start(struct channel *C)
bgp_init_bucket_table(c);
bgp_init_prefix_table(c);
+ c->stale_timer = tm_new_init(c->pool, bgp_long_lived_stale_timeout, c, 0, 0);
+
c->next_hop_addr = c->cf->next_hop_addr;
c->link_addr = IPA_NONE;
c->packets_to_send = 0;
@@ -1634,6 +1726,10 @@ bgp_postconfig(struct proto_config *CF)
if (cf->multihop < 0)
cf->multihop = internal ? 64 : 0;
+ /* LLGR mode default based on GR mode */
+ if (cf->llgr_mode < 0)
+ cf->llgr_mode = cf->gr_mode ? BGP_LLGR_AWARE : 0;
+
/* Link check for single-hop BGP by default */
if (cf->check_link < 0)
cf->check_link = !cf->multihop;
@@ -1676,6 +1772,9 @@ bgp_postconfig(struct proto_config *CF)
if (cf->multihop && cf->bfd && ipa_zero(cf->local_ip))
cf_error("Multihop BGP with BFD requires specified local address");
+ if (!cf->gr_mode && cf->llgr_mode)
+ cf_error("Long-lived graceful restart requires basic graceful restart");
+
struct bgp_channel_config *cc;
WALK_LIST(cc, CF->channels)
@@ -1706,10 +1805,16 @@ bgp_postconfig(struct proto_config *CF)
if (!cc->gw_mode)
cc->gw_mode = cf->multihop ? GW_RECURSIVE : GW_DIRECT;
- /* Default based on proto config */
+ /* Defaults based on proto config */
if (cc->gr_able == 0xff)
cc->gr_able = (cf->gr_mode == BGP_GR_ABLE);
+ if (cc->llgr_able == 0xff)
+ cc->llgr_able = (cf->llgr_mode == BGP_LLGR_ABLE);
+
+ if (cc->llgr_time == ~0U)
+ cc->llgr_time = cf->llgr_time;
+
/* Default values of IGP tables */
if ((cc->gw_mode == GW_RECURSIVE) && !cc->desc->no_igp)
{
@@ -1885,6 +1990,7 @@ static char *bgp_state_names[] = { "Idle", "Connect", "Active", "OpenSent", "Ope
static char *bgp_err_classes[] = { "", "Error: ", "Socket: ", "Received: ", "BGP Error: ", "Automatic shutdown: ", ""};
static char *bgp_misc_errors[] = { "", "Neighbor lost", "Invalid next hop", "Kernel MD5 auth failed", "No listening socket", "Link down", "BFD session down", "Graceful restart"};
static char *bgp_auto_errors[] = { "", "Route limit exceeded"};
+static char *bgp_gr_states[] = { "None", "Regular", "Long-lived"};
static const char *
bgp_last_errmsg(struct bgp_proto *p)
@@ -1963,6 +2069,7 @@ bgp_show_capabilities(struct bgp_proto *p UNUSED, struct bgp_caps *caps)
uint any_gr_able = 0;
uint any_add_path = 0;
uint any_ext_next_hop = 0;
+ uint any_llgr_able = 0;
u32 *afl1 = alloca(caps->af_count * sizeof(u32));
u32 *afl2 = alloca(caps->af_count * sizeof(u32));
uint afn1, afn2;
@@ -1973,6 +2080,7 @@ bgp_show_capabilities(struct bgp_proto *p UNUSED, struct bgp_caps *caps)
any_gr_able |= ac->gr_able;
any_add_path |= ac->add_path;
any_ext_next_hop |= ac->ext_next_hop;
+ any_llgr_able |= ac->llgr_able;
}
if (any_mp_bgp)
@@ -2052,6 +2160,32 @@ bgp_show_capabilities(struct bgp_proto *p UNUSED, struct bgp_caps *caps)
if (caps->enhanced_refresh)
cli_msg(-1006, " Enhanced refresh");
+
+ if (caps->llgr_aware)
+ cli_msg(-1006, " Long-lived graceful restart");
+
+ if (any_llgr_able)
+ {
+ u32 stale_time = 0;
+
+ afn1 = afn2 = 0;
+ WALK_AF_CAPS(caps, ac)
+ {
+ stale_time = MAX(stale_time, ac->llgr_time);
+
+ if (ac->llgr_able && ac->llgr_time)
+ afl1[afn1++] = ac->afi;
+
+ if (ac->llgr_flags & BGP_GRF_FORWARDING)
+ afl2[afn2++] = ac->afi;
+ }
+
+ /* Continues from llgr_aware */
+ cli_msg(-1006, " LL stale time: %u", stale_time);
+
+ bgp_show_afis(-1006, " AF supported:", afl1, afn1);
+ bgp_show_afis(-1006, " AF preserved:", afl2, afn2);
+ }
}
static void
@@ -2118,6 +2252,12 @@ bgp_show_proto_info(struct proto *P)
{
channel_show_info(&c->c);
+ if (p->gr_active_num)
+ cli_msg(-1006, " Neighbor GR: %s", bgp_gr_states[c->gr_active]);
+
+ if (tm_active(c->stale_timer))
+ cli_msg(-1006, " LL stale timer: %t/-", tm_remains(c->stale_timer));
+
if (c->c.channel_state == CS_UP)
{
if (ipa_zero(c->link_addr))
diff --git a/proto/bgp/bgp.h b/proto/bgp/bgp.h
index 1235ee78..6f0a5587 100644
--- a/proto/bgp/bgp.h
+++ b/proto/bgp/bgp.h
@@ -107,9 +107,11 @@ struct bgp_config {
int allow_local_as; /* Allow that number of local ASNs in incoming AS_PATHs */
int allow_local_pref; /* Allow LOCAL_PREF in EBGP sessions */
int gr_mode; /* Graceful restart mode (BGP_GR_*) */
+ int llgr_mode; /* Long-lived graceful restart mode (BGP_LLGR_*) */
int setkey; /* Set MD5 password to system SA/SP database */
/* Times below are in seconds */
unsigned gr_time; /* Graceful restart timeout */
+ unsigned llgr_time; /* Long-lived graceful restart stale time */
unsigned connect_delay_time; /* Minimum delay between connect attempts */
unsigned connect_retry_time; /* Timeout for connect attempts */
unsigned hold_time, initial_hold_time;
@@ -138,6 +140,8 @@ struct bgp_channel_config {
u8 gw_mode; /* How we compute route gateway from next_hop attr, see GW_* */
u8 secondary; /* Accept also non-best routes (i.e. RA_ACCEPTED) */
u8 gr_able; /* Allow full graceful restart for the channel */
+ u8 llgr_able; /* Allow full long-lived GR for the channel */
+ uint llgr_time; /* Long-lived graceful restart stale time */
u8 ext_next_hop; /* Allow both IPv4 and IPv6 next hops */
u8 add_path; /* Use ADD-PATH extension [RFC 7911] */
@@ -166,12 +170,26 @@ struct bgp_channel_config {
/* For GR capability per-AF flags */
#define BGP_GRF_FORWARDING 0x80
+#define BGP_LLGR_ABLE 1
+#define BGP_LLGR_AWARE 2
+
+#define BGP_LLGRF_FORWARDING 0x80
+
+#define BGP_GRS_NONE 0 /* No GR */
+#define BGP_GRS_ACTIVE 1 /* Graceful restart per RFC 4724 */
+#define BGP_GRS_LLGR 2 /* Long-lived GR phase (stale timer active) */
+
+#define BGP_BFD_GRACEFUL 2 /* BFD down triggers graceful restart */
+
struct bgp_af_caps {
u32 afi;
u8 ready; /* Multiprotocol capability, RFC 4760 */
u8 gr_able; /* Graceful restart support, RFC 4724 */
u8 gr_af_flags; /* Graceful restart per-AF flags */
+ u8 llgr_able; /* Long-lived GR, RFC draft */
+ u32 llgr_time; /* Long-lived GR stale time */
+ u8 llgr_flags; /* Long-lived GR per-AF flags */
u8 ext_next_hop; /* Extended IPv6 next hop, RFC 5549 */
u8 add_path; /* Multiple paths support, RFC 7911 */
};
@@ -188,6 +206,8 @@ struct bgp_caps {
u8 gr_flags; /* Graceful restart flags */
u16 gr_time; /* Graceful restart time in seconds */
+ u8 llgr_aware; /* Long-lived GR capability, RFC draft */
+
u16 af_count; /* Number of af_data items */
struct bgp_af_caps af_data[0]; /* Per-AF capability data */
@@ -243,6 +263,7 @@ struct bgp_proto {
u8 route_refresh; /* Route refresh allowed to send [RFC 2918] */
u8 enhanced_refresh; /* Enhanced refresh is negotiated [RFC 7313] */
u8 gr_ready; /* Neighbor could do graceful restart */
+ u8 llgr_ready; /* Neighbor could do Long-lived GR, implies gr_ready */
u8 gr_active_num; /* Neighbor is doing GR, number of active channels */
u8 channel_count; /* Number of active channels */
u32 *afi_map; /* Map channel index -> AFI */
@@ -291,11 +312,14 @@ struct bgp_channel {
u32 packets_to_send; /* Bitmap of packet types to be sent */
- u8 gr_ready; /* Neighbor could do GR on this AF */
- u8 gr_active; /* Neighbor is doing GR and keeping fwd state */
-
u8 ext_next_hop; /* Session allows both IPv4 and IPv6 next hops */
+ u8 gr_ready; /* Neighbor could do GR on this AF */
+ u8 gr_active; /* Neighbor is doing GR (BGP_GRS_*) */
+
+ timer *stale_timer; /* Long-lived stale timer for LLGR */
+ u32 stale_time; /* Stored LLGR stale time from last session */
+
u8 add_path_rx; /* Session expects receive of ADD-PATH extended NLRI */
u8 add_path_tx; /* Session expects transmit of ADD-PATH extended NLRI */
@@ -505,6 +529,7 @@ void bgp_free_prefix(struct bgp_channel *c, struct bgp_prefix *bp);
int bgp_rte_better(struct rte *, struct rte *);
int bgp_rte_mergable(rte *pri, rte *sec);
int bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best);
+struct rte *bgp_rte_modify_stale(struct rte *r, struct linpool *pool);
void bgp_rt_notify(struct proto *P, struct channel *C, net *n, rte *new, rte *old);
int bgp_import_control(struct proto *, struct rte **, struct linpool *);
int bgp_get_attr(struct eattr *e, byte *buf, int buflen);
@@ -645,6 +670,9 @@ void bgp_update_next_hop(struct bgp_export_state *s, eattr *a, ea_list **to);
#define BGP_COMM_NO_ADVERTISE 0xffffff02 /* Don't export at all */
#define BGP_COMM_NO_EXPORT_SUBCONFED 0xffffff03 /* NO_EXPORT even in local confederation */
+#define BGP_COMM_LLGR_STALE 0xffff0006 /* Route is stale according to LLGR */
+#define BGP_COMM_NO_LLGR 0xffff0007 /* Do not treat the route according to LLGR */
+
/* Origins */
#define ORIGIN_IGP 0
diff --git a/proto/bgp/config.Y b/proto/bgp/config.Y
index 7583f7d1..120b1e88 100644
--- a/proto/bgp/config.Y
+++ b/proto/bgp/config.Y
@@ -28,7 +28,8 @@ CF_KEYWORDS(BGP, LOCAL, NEIGHBOR, AS, HOLD, TIME, CONNECT, RETRY, KEEPALIVE,
BGP_CLUSTER_LIST, IGP, TABLE, GATEWAY, DIRECT, RECURSIVE, MED, TTL,
SECURITY, DETERMINISTIC, SECONDARY, ALLOW, BFD, ADD, PATHS, RX, TX,
GRACEFUL, RESTART, AWARE, CHECK, LINK, PORT, EXTENDED, MESSAGES, SETKEY,
- STRICT, BIND, CONFEDERATION, MEMBER, MULTICAST, FLOW4, FLOW6)
+ STRICT, BIND, CONFEDERATION, MEMBER, MULTICAST, FLOW4, FLOW6, LONG,
+ LIVED, STALE)
%type ] bgp_afi
@@ -63,6 +64,8 @@ bgp_proto_start: proto_start BGP {
BGP_CFG->default_local_pref = 100;
BGP_CFG->gr_mode = BGP_GR_AWARE;
BGP_CFG->gr_time = 120;
+ BGP_CFG->llgr_mode = -1;
+ BGP_CFG->llgr_time = 3600;
BGP_CFG->setkey = 1;
BGP_CFG->check_link = -1;
}
@@ -161,9 +164,13 @@ bgp_proto:
| bgp_proto GRACEFUL RESTART bool ';' { BGP_CFG->gr_mode = $4; }
| bgp_proto GRACEFUL RESTART AWARE ';' { BGP_CFG->gr_mode = BGP_GR_AWARE; }
| bgp_proto GRACEFUL RESTART TIME expr ';' { BGP_CFG->gr_time = $5; }
+ | bgp_proto LONG LIVED GRACEFUL RESTART bool ';' { BGP_CFG->llgr_mode = $6; }
+ | bgp_proto LONG LIVED GRACEFUL RESTART AWARE ';' { BGP_CFG->llgr_mode = BGP_LLGR_AWARE; }
+ | bgp_proto LONG LIVED STALE TIME expr ';' { BGP_CFG->llgr_time = $6; }
| bgp_proto TTL SECURITY bool ';' { BGP_CFG->ttl_security = $4; }
| bgp_proto CHECK LINK bool ';' { BGP_CFG->check_link = $4; }
| bgp_proto BFD bool ';' { BGP_CFG->bfd = $3; cf_check_bfd($3); }
+ | bgp_proto BFD GRACEFUL ';' { BGP_CFG->bfd = BGP_BFD_GRACEFUL; cf_check_bfd(1); }
;
bgp_afi:
@@ -199,6 +206,8 @@ bgp_channel_start: bgp_afi
BGP_CC->afi = $1;
BGP_CC->desc = desc;
BGP_CC->gr_able = 0xff; /* undefined */
+ BGP_CC->llgr_able = 0xff; /* undefined */
+ BGP_CC->llgr_time = ~0U; /* undefined */
}
};
@@ -214,6 +223,8 @@ bgp_channel_item:
| GATEWAY RECURSIVE { BGP_CC->gw_mode = GW_RECURSIVE; }
| SECONDARY bool { BGP_CC->secondary = $2; }
| GRACEFUL RESTART bool { BGP_CC->gr_able = $3; }
+ | LONG LIVED GRACEFUL RESTART bool { BGP_CC->llgr_able = $5; }
+ | LONG LIVED STALE TIME expr { BGP_CC->llgr_time = $5; }
| EXTENDED NEXT HOP bool { BGP_CC->ext_next_hop = $4; }
| ADD PATHS RX { BGP_CC->add_path = BGP_ADD_PATH_RX; }
| ADD PATHS TX { BGP_CC->add_path = BGP_ADD_PATH_TX; }
diff --git a/proto/bgp/packets.c b/proto/bgp/packets.c
index c40b8ec2..ed1db04b 100644
--- a/proto/bgp/packets.c
+++ b/proto/bgp/packets.c
@@ -260,6 +260,9 @@ bgp_write_capabilities(struct bgp_conn *conn, byte *buf)
caps->gr_flags = p->p.gr_recovery ? BGP_GRF_RESTART : 0;
}
+ if (p->cf->llgr_mode)
+ caps->llgr_aware = 1;
+
/* Allocate and fill per-AF fields */
WALK_LIST(c, p->p.channels)
{
@@ -280,6 +283,15 @@ bgp_write_capabilities(struct bgp_conn *conn, byte *buf)
if (p->p.gr_recovery)
ac->gr_af_flags |= BGP_GRF_FORWARDING;
}
+
+ if (c->cf->llgr_able)
+ {
+ ac->llgr_able = 1;
+ ac->llgr_time = c->cf->llgr_time;
+
+ if (p->p.gr_recovery)
+ ac->llgr_flags |= BGP_LLGRF_FORWARDING;
+ }
}
/* Sort capability fields by AFI/SAFI */
@@ -289,9 +301,9 @@ bgp_write_capabilities(struct bgp_conn *conn, byte *buf)
/* Create capability list in buffer */
/*
- * Note that max length is ~ 20+14*af_count. With max 12 channels that is
- * 188. Option limit is 253 and buffer size is 4096, so we cannot overflow
- * unless we add new capabilities or more AFs.
+ * Note that max length is ~ 22+21*af_count. With max 12 channels that is
+ * 274. Option limit is 253 and buffer size is 4096, so we cannot overflow
+ * unless we add new capabilities or more AFs. XXXXX
*/
WALK_AF_CAPS(caps, ac)
@@ -384,6 +396,24 @@ bgp_write_capabilities(struct bgp_conn *conn, byte *buf)
*buf++ = 0; /* Capability data length */
}
+ if (caps->llgr_aware)
+ {
+ *buf++ = 71; /* Capability 71: Support for long-lived graceful restart */
+ *buf++ = 0; /* Capability data length, will be fixed later */
+ data = buf;
+
+ WALK_AF_CAPS(caps, ac)
+ if (ac->llgr_able)
+ {
+ put_af3(buf, ac->afi);
+ buf[3] = ac->llgr_flags;
+ put_u24(buf+4, ac->llgr_time);
+ buf += 7;
+ }
+
+ data[-1] = buf - data;
+ }
+
return buf;
}
@@ -508,11 +538,49 @@ bgp_read_capabilities(struct bgp_conn *conn, struct bgp_caps *caps, byte *pos, i
caps->enhanced_refresh = 1;
break;
+ case 71: /* Long lived graceful restart capability, RFC draft */
+ if (cl % 7)
+ goto err;
+
+ /* Presumably, only the last instance is valid */
+ WALK_AF_CAPS(caps, ac)
+ {
+ ac->llgr_able = 0;
+ ac->llgr_flags = 0;
+ ac->llgr_time = 0;
+ }
+
+ caps->llgr_aware = 1;
+
+ for (i = 0; i < cl; i += 7)
+ {
+ af = get_af3(pos+2+i);
+ ac = bgp_get_af_caps(caps, af);
+ ac->llgr_able = 1;
+ ac->llgr_flags = pos[2+i+3];
+ ac->llgr_time = get_u24(pos + 2+i+4);
+ }
+ break;
+
/* We can safely ignore all other capabilities */
}
ADVANCE(pos, len, 2 + cl);
}
+
+ /* The LLGR capability must be advertised together with the GR capability,
+ otherwise it must be disregarded */
+ if (!caps->gr_aware && caps->llgr_aware)
+ {
+ caps->llgr_aware = 0;
+ WALK_AF_CAPS(caps, ac)
+ {
+ ac->llgr_able = 0;
+ ac->llgr_flags = 0;
+ ac->llgr_time = 0;
+ }
+ }
+
return;
err:
@@ -1131,6 +1199,7 @@ bgp_rte_update(struct bgp_parse_state *s, net_addr *n, u32 path_id, rta *a0)
e->pflags = 0;
e->u.bgp.suppressed = 0;
+ e->u.bgp.stale = -1;
rte_update2(&s->channel->c, n, e, s->last_src);
}
diff --git a/proto/pipe/pipe.c b/proto/pipe/pipe.c
index 7aada37e..82ccf38a 100644
--- a/proto/pipe/pipe.c
+++ b/proto/pipe/pipe.c
@@ -78,6 +78,12 @@ pipe_rt_notify(struct proto *P, struct channel *src_ch, net *n, rte *new, rte *o
e->pref = new->pref;
e->pflags = new->pflags;
+#ifdef CONFIG_BGP
+ /* Hack to cleanup cached value */
+ if (e->attrs->src->proto->proto == &proto_bgp)
+ e->u.bgp.stale = -1;
+#endif
+
src = a->src;
}
else