diff options
| -rw-r--r-- | doc/bird.sgml | 20 | ||||
| -rw-r--r-- | proto/bgp/bgp.c | 15 | ||||
| -rw-r--r-- | proto/bgp/bgp.h | 5 | ||||
| -rw-r--r-- | proto/bgp/config.Y | 6 | ||||
| -rw-r--r-- | proto/bgp/packets.c | 20 |
5 files changed, 58 insertions, 8 deletions
diff --git a/doc/bird.sgml b/doc/bird.sgml index badfe649..b9ccf9f7 100644 --- a/doc/bird.sgml +++ b/doc/bird.sgml @@ -2783,9 +2783,16 @@ using the following configuration parameters: <tag><label id="bgp-hold-time">hold time <m/number/</tag> Time in seconds to wait for a Keepalive message from the other side - before considering the connection stale. Default: depends on agreement - with the neighboring router, we prefer 240 seconds if the other side is - willing to accept it. + before considering the connection stale. The effective value is + negotiated during session establishment and it is a minimum of this + configured value and the value proposed by the peer. The zero value has + a special meaning, signifying that no keepalives are used. Default: 240 + seconds. + + <tag><label id="bgp-min-hold-time">min hold time <m/number/</tag> + Minimum value of the hold time that is accepted during session negotiation. + If the peer proposes a lower value, the session is rejected with error. + Default: none. <tag><label id="bgp-startup-hold-time">startup hold time <m/number/</tag> Value of the hold timer used before the routers have a chance to exchange @@ -2793,8 +2800,15 @@ using the following configuration parameters: <tag><label id="bgp-keepalive-time">keepalive time <m/number/</tag> Delay in seconds between sending of two consecutive Keepalive messages. + The effective value depends on the negotiated hold time, as it is scaled + to maintain proportion between the keepalive time and the hold time. Default: One third of the hold time. + <tag><label id="bgp-min-keepalive-time">min keepalive time <m/number/</tag> + Minimum value of the keepalive time that is accepted during session + negotiation. If the proposed hold time would lead to a lower value of + the keepalive time, the session is rejected with error. Default: none. + <tag><label id="bgp-connect-delay-time">connect delay time <m/number/</tag> Delay in seconds between protocol startup and the first attempt to connect. Default: 5 seconds. diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c index 2f8da1af..e8e65ad7 100644 --- a/proto/bgp/bgp.c +++ b/proto/bgp/bgp.c @@ -2075,6 +2075,21 @@ bgp_postconfig(struct proto_config *CF) if (internal && cf->enforce_first_as) cf_error("Enforce first AS check is requires EBGP sessions"); + if (cf->keepalive_time > cf->hold_time) + cf_error("Keepalive time must be at most hold time"); + + if (cf->keepalive_time > (cf->hold_time / 2)) + log(L_WARN "Keepalive time should be at most 1/2 of hold time"); + + if (cf->min_hold_time > cf->hold_time) + cf_error("Min hold time (%u) exceeds hold time (%u)", + cf->min_hold_time, cf->hold_time); + + uint keepalive_time = cf->keepalive_time ?: cf->hold_time / 3; + if (cf->min_keepalive_time > keepalive_time) + cf_error("Min keepalive time (%u) exceeds keepalive time (%u)", + cf->min_keepalive_time, keepalive_time); + struct bgp_channel_config *cc; BGP_CF_WALK_CHANNELS(cf, cc) diff --git a/proto/bgp/bgp.h b/proto/bgp/bgp.h index b87e0fc4..5a680022 100644 --- a/proto/bgp/bgp.h +++ b/proto/bgp/bgp.h @@ -120,8 +120,11 @@ struct bgp_config { 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; + unsigned hold_time; + unsigned min_hold_time; /* Minimum accepted hold time */ + unsigned initial_hold_time; unsigned keepalive_time; + unsigned min_keepalive_time; /* Minimum accepted keepalive time */ unsigned error_amnesia_time; /* Errors are forgotten after */ unsigned error_delay_time_min; /* Time to wait after an error is detected */ unsigned error_delay_time_max; diff --git a/proto/bgp/config.Y b/proto/bgp/config.Y index b4edf2c5..0be50b5e 100644 --- a/proto/bgp/config.Y +++ b/proto/bgp/config.Y @@ -154,7 +154,8 @@ bgp_proto: | bgp_proto RS CLIENT bool ';' { BGP_CFG->rs_client = $4; } | bgp_proto CONFEDERATION expr ';' { BGP_CFG->confederation = $3; } | bgp_proto CONFEDERATION MEMBER bool ';' { BGP_CFG->confederation_member = $4; } - | bgp_proto HOLD TIME expr ';' { BGP_CFG->hold_time = $4; } + | bgp_proto HOLD TIME expr ';' { BGP_CFG->hold_time = $4; if (($4 && $4<3) || ($4>65535)) cf_error("Hold time must be in range 3-65535 or zero"); } + | bgp_proto MIN HOLD TIME expr ';' { BGP_CFG->min_hold_time = $5; } | bgp_proto STARTUP HOLD TIME expr ';' { BGP_CFG->initial_hold_time = $5; } | bgp_proto DIRECT ';' { BGP_CFG->multihop = 0; } | bgp_proto MULTIHOP ';' { BGP_CFG->multihop = 64; } @@ -178,7 +179,8 @@ bgp_proto: | bgp_proto START DELAY TIME expr ';' { BGP_CFG->connect_delay_time = $5; log(L_WARN "%s: Start delay time option is deprecated, use connect delay time", this_proto->name); } | bgp_proto CONNECT DELAY TIME expr ';' { BGP_CFG->connect_delay_time = $5; } | bgp_proto CONNECT RETRY TIME expr ';' { BGP_CFG->connect_retry_time = $5; } - | bgp_proto KEEPALIVE TIME expr ';' { BGP_CFG->keepalive_time = $4; } + | bgp_proto KEEPALIVE TIME expr ';' { BGP_CFG->keepalive_time = $4; if (($4<1) || ($4>65535)) cf_error("Keepalive time must be in range 1-65535"); } + | bgp_proto MIN KEEPALIVE TIME expr ';' { BGP_CFG->min_keepalive_time = $5; } | bgp_proto ERROR FORGET TIME expr ';' { BGP_CFG->error_amnesia_time = $5; } | bgp_proto ERROR WAIT TIME expr ',' expr ';' { BGP_CFG->error_delay_time_min = $5; BGP_CFG->error_delay_time_max = $7; } | bgp_proto DISABLE AFTER ERROR bool ';' { BGP_CFG->disable_after_error = $5; } diff --git a/proto/bgp/packets.c b/proto/bgp/packets.c index 506268c9..04e4505c 100644 --- a/proto/bgp/packets.c +++ b/proto/bgp/packets.c @@ -847,9 +847,25 @@ bgp_rx_open(struct bgp_conn *conn, byte *pkt, uint len) if (bgp_read_options(conn, pkt+29, pkt[28], len-29) < 0) return; + /* RFC 4271 4.2 - hold time must be either 0 or at least 3 */ if (hold > 0 && hold < 3) { bgp_error(conn, 2, 6, pkt+22, 2); return; } + /* Compute effective hold and keepalive times */ + uint hold_time = MIN(hold, p->cf->hold_time); + uint keepalive_time = p->cf->keepalive_time ? + (p->cf->keepalive_time * hold_time / p->cf->hold_time) : + hold_time / 3; + + /* Keepalive time might be rounded down to zero */ + if (hold_time && !keepalive_time) + keepalive_time = 1; + + /* Check effective values against configured minimums */ + if ((hold_time < p->cf->min_hold_time) || + (keepalive_time < p->cf->min_keepalive_time)) + { bgp_error(conn, 2, 6, pkt+22, 2); return; } + /* RFC 6286 2.2 - router ID is nonzero and AS-wide unique */ if (!id || (p->is_internal && id == p->local_id)) { bgp_error(conn, 2, 3, pkt+24, -4); return; } @@ -947,8 +963,8 @@ bgp_rx_open(struct bgp_conn *conn, byte *pkt, uint len) } /* Update our local variables */ - conn->hold_time = MIN(hold, p->cf->hold_time); - conn->keepalive_time = p->cf->keepalive_time ? : conn->hold_time / 3; + conn->hold_time = hold_time; + conn->keepalive_time = keepalive_time; conn->as4_session = conn->local_caps->as4_support && caps->as4_support; conn->ext_messages = conn->local_caps->ext_messages && caps->ext_messages; p->remote_id = id; |