From 3f9b7bfe9ff050430a5886b22a5ab11b5f253048 Mon Sep 17 00:00:00 2001 From: Ondrej Zajicek Date: Wed, 18 Nov 2009 20:32:36 +0100 Subject: Implements option that controls IPv6 BGP next hops when lladdr is missing. --- proto/bgp/bgp.c | 4 ++++ proto/bgp/bgp.h | 5 +++++ proto/bgp/config.Y | 6 +++++- proto/bgp/packets.c | 47 ++++++++++++++++++++++++++++++++--------------- 4 files changed, 46 insertions(+), 16 deletions(-) (limited to 'proto/bgp') diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c index b38c6b1..cde0276 100644 --- a/proto/bgp/bgp.c +++ b/proto/bgp/bgp.c @@ -886,6 +886,10 @@ bgp_check(struct bgp_config *c) if ((c->local_as == c->remote_as) && (c->rs_client)) cf_error("Only external neighbor can be RS client"); + + /* Different default based on rs_client */ + if (c->missing_lladdr == 0) + c->missing_lladdr = c->rs_client ? MLL_DROP : MLL_SELF; } static char *bgp_state_names[] = { "Idle", "Connect", "Active", "OpenSent", "OpenConfirm", "Established", "Close" }; diff --git a/proto/bgp/bgp.h b/proto/bgp/bgp.h index c487aaf..c4d0335 100644 --- a/proto/bgp/bgp.h +++ b/proto/bgp/bgp.h @@ -23,6 +23,7 @@ struct bgp_config { ip_addr multihop_via; /* Multihop: address to route to */ ip_addr source_addr; /* Source address to use */ int next_hop_self; /* Always set next hop to local IP address */ + int missing_lladdr; /* What we will do when we don' know link-local addr, see MLL_* */ int compare_path_lengths; /* Use path lengths when selecting best route */ int prefer_older; /* Prefer older routes according to RFC 5004 */ u32 default_local_pref; /* Default value for LOCAL_PREF attribute */ @@ -46,6 +47,10 @@ struct bgp_config { char *password; /* Password used for MD5 authentication */ }; +#define MLL_SELF 1 +#define MLL_DROP 2 +#define MLL_IGNORE 3 + struct bgp_conn { struct bgp_proto *bgp; struct birdsock *sk; diff --git a/proto/bgp/config.Y b/proto/bgp/config.Y index 9401175..3576946 100644 --- a/proto/bgp/config.Y +++ b/proto/bgp/config.Y @@ -22,7 +22,8 @@ CF_KEYWORDS(BGP, LOCAL, NEIGHBOR, AS, HOLD, TIME, CONNECT, RETRY, KEEPALIVE, BGP_PATH, BGP_LOCAL_PREF, BGP_MED, BGP_ORIGIN, BGP_NEXT_HOP, BGP_ATOMIC_AGGR, BGP_AGGREGATOR, BGP_COMMUNITY, SOURCE, ADDRESS, PASSWORD, RR, RS, CLIENT, CLUSTER, ID, AS4, ADVERTISE, IPV4, - CAPABILITIES, LIMIT, PASSIVE, PREFER, OLDER) + CAPABILITIES, LIMIT, PASSIVE, PREFER, OLDER, MISSING, LLADDR, + DROP, IGNORE) CF_GRAMMAR @@ -64,6 +65,9 @@ bgp_proto: | bgp_proto KEEPALIVE TIME expr ';' { BGP_CFG->keepalive_time = $4; } | bgp_proto MULTIHOP expr VIA ipa ';' { BGP_CFG->multihop = $3; BGP_CFG->multihop_via = $5; } | bgp_proto NEXT HOP SELF ';' { BGP_CFG->next_hop_self = 1; } + | bgp_proto MISSING LLADDR SELF ';' { BGP_CFG->missing_lladdr = MLL_SELF; } + | bgp_proto MISSING LLADDR DROP ';' { BGP_CFG->missing_lladdr = MLL_DROP; } + | bgp_proto MISSING LLADDR IGNORE ';' { BGP_CFG->missing_lladdr = MLL_IGNORE; } | bgp_proto PATH METRIC bool ';' { BGP_CFG->compare_path_lengths = $4; } | bgp_proto PREFER OLDER bool ';' { BGP_CFG->prefer_older = $4; } | bgp_proto DEFAULT BGP_MED expr ';' { BGP_CFG->default_med = $4; } diff --git a/proto/bgp/packets.c b/proto/bgp/packets.c index d126fe5..4176c9f 100644 --- a/proto/bgp/packets.c +++ b/proto/bgp/packets.c @@ -199,7 +199,7 @@ bgp_create_update(struct bgp_conn *conn, byte *buf) if (a_size < 0) { - log(L_ERR "%s: Attribute list too long, skipping corresponding route group", p->p.name); + log(L_ERR "%s: Attribute list too long, skipping corresponding routes", p->p.name); bgp_flush_prefixes(p, buck); rem_node(&buck->send_node); bgp_free_bucket(p, buck); @@ -234,9 +234,9 @@ bgp_create_update(struct bgp_conn *conn, byte *buf) { struct bgp_proto *p = conn->bgp; struct bgp_bucket *buck; - int size, second; + int size, second, rem_stored; int remains = BGP_MAX_PACKET_LENGTH - BGP_HEADER_LENGTH - 4; - byte *w, *tmp, *tstart; + byte *w, *w_stored, *tmp, *tstart; ip_addr *ipp, ip, ip_ll; ea_list *ea; eattr *nh; @@ -272,28 +272,25 @@ bgp_create_update(struct bgp_conn *conn, byte *buf) } DBG("Processing bucket %p\n", buck); - size = bgp_encode_attrs(p, w, buck->eattrs, 2048); + rem_stored = remains; + w_stored = w; + size = bgp_encode_attrs(p, w, buck->eattrs, 2048); if (size < 0) { - log(L_ERR "%s: Attribute list too long, ignoring corresponding route group", p->p.name); + log(L_ERR "%s: Attribute list too long, skipping corresponding routes", p->p.name); bgp_flush_prefixes(p, buck); rem_node(&buck->send_node); bgp_free_bucket(p, buck); continue; } - w += size; remains -= size; - tstart = tmp = bgp_attach_attr_wa(&ea, bgp_linpool, BA_MP_REACH_NLRI, remains-8); - *tmp++ = 0; - *tmp++ = BGP_AF_IPV6; - *tmp++ = 1; - nh = ea_find(buck->eattrs, EA_CODE(EAP_BGP, BA_NEXT_HOP)); - ASSERT(nh); - /* We have two addresses here in 'nh'. Really. + /* We have two addresses here in NEXT_HOP eattr. Really. Unless NEXT_HOP was modified by filter */ + nh = ea_find(buck->eattrs, EA_CODE(EAP_BGP, BA_NEXT_HOP)); + ASSERT(nh); second = (nh->u.ptr->length == NEXT_HOP_LENGTH); ipp = (ip_addr *) nh->u.ptr->data; ip = ipp[0]; @@ -322,12 +319,32 @@ bgp_create_update(struct bgp_conn *conn, byte *buf) ip_ll = ipp[1]; else { - ip = p->source_addr; - ip_ll = p->local_link; + switch (p->cf->missing_lladdr) + { + case MLL_SELF: + ip = p->source_addr; + ip_ll = p->local_link; + break; + case MLL_DROP: + log(L_ERR "%s: Missing link-local next hop address, skipping corresponding routes", p->p.name); + w = w_stored; + remains = rem_stored; + bgp_flush_prefixes(p, buck); + rem_node(&buck->send_node); + bgp_free_bucket(p, buck); + continue; + case MLL_IGNORE: + break; + } } } } + tstart = tmp = bgp_attach_attr_wa(&ea, bgp_linpool, BA_MP_REACH_NLRI, remains-8); + *tmp++ = 0; + *tmp++ = BGP_AF_IPV6; + *tmp++ = 1; + if (ipa_nonzero(ip_ll)) { *tmp++ = 32; -- cgit v1.2.3