From 5d6ca220850c615126ea6820f8c05528269feec6 Mon Sep 17 00:00:00 2001 From: "Ondrej Zajicek (work)" Date: Tue, 19 Jul 2016 14:23:41 +0200 Subject: Babel: Send wildcard retractions on shutdown and startup MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This makes BIRD send a wildcard retraction on all interfaces before shutting down and right after starting up. This helps ensure that neighbours will discard the announced routes as soon as possible, rather than only after the normal timeout procedures. Signed-off-by: Toke Høiland-Jørgensen --- proto/babel/babel.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++---- proto/babel/babel.h | 2 +- proto/babel/packets.c | 25 ++++++++++++++++++------- 3 files changed, 65 insertions(+), 12 deletions(-) (limited to 'proto') diff --git a/proto/babel/babel.c b/proto/babel/babel.c index 8204838b..67e1d8be 100644 --- a/proto/babel/babel.c +++ b/proto/babel/babel.c @@ -834,8 +834,8 @@ babel_send_retraction(struct babel_iface *ifa, ip_addr prefix, int plen) struct babel_proto *p = ifa->proto; union babel_msg msg = {}; - TRACE(D_PACKETS, "Sending retraction for %I/%d router-id %lR seqno %d", - prefix, plen, p->router_id, p->update_seqno); + TRACE(D_PACKETS, "Sending retraction for %I/%d seqno %d", + prefix, plen, p->update_seqno); msg.type = BABEL_TLV_UPDATE; msg.update.plen = plen; @@ -843,7 +843,23 @@ babel_send_retraction(struct babel_iface *ifa, ip_addr prefix, int plen) msg.update.seqno = p->update_seqno; msg.update.metric = BABEL_INFINITY; msg.update.prefix = prefix; - msg.update.router_id = p->router_id; + + babel_enqueue(&msg, ifa); +} + +static void +babel_send_wildcard_retraction(struct babel_iface *ifa) +{ + struct babel_proto *p = ifa->proto; + union babel_msg msg = {}; + + TRACE(D_PACKETS, "Sending wildcard retraction on %s", ifa->ifname); + + msg.type = BABEL_TLV_UPDATE; + msg.update.wildcard = 1; + msg.update.interval = ifa->cf->update_interval; + msg.update.seqno = p->update_seqno; + msg.update.metric = BABEL_INFINITY; babel_enqueue(&msg, ifa); } @@ -1099,7 +1115,7 @@ babel_handle_update(union babel_msg *m, struct babel_iface *ifa) /* Retraction */ if (msg->metric == BABEL_INFINITY) { - if (msg->ae == BABEL_AE_WILDCARD) + if (msg->wildcard) { /* * Special case: This is a retraction of all prefixes announced by this @@ -1347,6 +1363,7 @@ babel_iface_start(struct babel_iface *ifa) ifa->up = 1; babel_send_hello(ifa, 0); + babel_send_wildcard_retraction(ifa); babel_send_wildcard_request(ifa); babel_send_update(ifa, 0); /* Full update */ } @@ -2056,6 +2073,30 @@ babel_start(struct proto *P) return PS_UP; } +static inline void +babel_iface_shutdown(struct babel_iface *ifa) +{ + if (ifa->sk) + { + babel_send_wildcard_retraction(ifa); + babel_send_queue(ifa); + } +} + +static int +babel_shutdown(struct proto *P) +{ + struct babel_proto *p = (void *) P; + struct babel_iface *ifa; + + TRACE(D_EVENTS, "Shutdown requested"); + + WALK_LIST(ifa, p->interfaces) + babel_iface_shutdown(ifa); + + return PS_DOWN; +} + static int babel_reconfigure(struct proto *P, struct proto_config *c) { @@ -2083,6 +2124,7 @@ struct protocol proto_babel = { .init = babel_init, .dump = babel_dump, .start = babel_start, + .shutdown = babel_shutdown, .reconfigure = babel_reconfigure, .get_route_info = babel_get_route_info, .get_attr = babel_get_attr diff --git a/proto/babel/babel.h b/proto/babel/babel.h index 7b5037ab..481c88a7 100644 --- a/proto/babel/babel.h +++ b/proto/babel/babel.h @@ -268,7 +268,7 @@ struct babel_msg_ihu { struct babel_msg_update { u8 type; - u8 ae; + u8 wildcard; u8 plen; u16 interval; u16 seqno; diff --git a/proto/babel/packets.c b/proto/babel/packets.c index d0cc613e..65dd6853 100644 --- a/proto/babel/packets.c +++ b/proto/babel/packets.c @@ -462,7 +462,6 @@ babel_read_update(struct babel_tlv *hdr, union babel_msg *m, struct babel_msg_update *msg = &m->update; msg->type = BABEL_TLV_UPDATE; - msg->ae = tlv->ae; msg->interval = get_time16(&tlv->interval); msg->seqno = get_u16(&tlv->seqno); msg->metric = get_u16(&tlv->metric); @@ -480,8 +479,7 @@ babel_read_update(struct babel_tlv *hdr, union babel_msg *m, if (tlv->plen > 0) return PARSE_ERROR; - msg->plen = 0; - msg->prefix = IPA_NONE; + msg->wildcard = 1; break; case BABEL_AE_IP4: @@ -550,8 +548,11 @@ babel_write_update(struct babel_tlv *hdr, union babel_msg *m, * When needed, we write Router-ID TLV before Update TLV and return size of * both of them. There is enough space for the Router-ID TLV, because * sizeof(struct babel_tlv_router_id) == sizeof(struct babel_tlv_update). + * + * Router ID is not used for retractions, so do not us it in such case. */ - if (!state->router_id_seen || (msg->router_id != state->router_id)) + if ((msg->metric < BABEL_INFINITY) && + (!state->router_id_seen || (msg->router_id != state->router_id))) { len0 = babel_write_router_id(hdr, msg->router_id, state, max_len); tlv = (struct babel_tlv_update *) NEXT_TLV(tlv); @@ -564,12 +565,22 @@ babel_write_update(struct babel_tlv *hdr, union babel_msg *m, memset(tlv, 0, sizeof(struct babel_tlv_update)); TLV_HDR(tlv, BABEL_TLV_UPDATE, len); - tlv->ae = BABEL_AE_IP6; - tlv->plen = msg->plen; + + if (msg->wildcard) + { + tlv->ae = BABEL_AE_WILDCARD; + tlv->plen = 0; + } + else + { + tlv->ae = BABEL_AE_IP6; + tlv->plen = msg->plen; + put_ip6_px(tlv->addr, msg->prefix, msg->plen); + } + put_time16(&tlv->interval, msg->interval); put_u16(&tlv->seqno, msg->seqno); put_u16(&tlv->metric, msg->metric); - put_ip6_px(tlv->addr, msg->prefix, msg->plen); return len0 + len; } -- cgit v1.2.3