From 06e0d1b692d8a190c3f1d073c5c557d8efe78b17 Mon Sep 17 00:00:00 2001 From: Ondrej Zajicek Date: Sat, 18 Jul 2015 13:38:21 +0200 Subject: BGP: Extended messages support Implements draft-ietf-idr-bgp-extended-messages-10, for now undocumented and with temporary private capability number. --- proto/bgp/bgp.c | 22 ++++++++++++++++------ proto/bgp/bgp.h | 13 +++++++++++-- proto/bgp/config.Y | 3 ++- proto/bgp/packets.c | 29 ++++++++++++++++++++++++----- 4 files changed, 53 insertions(+), 14 deletions(-) (limited to 'proto') diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c index 9e28b278..f549b0ed 100644 --- a/proto/bgp/bgp.c +++ b/proto/bgp/bgp.c @@ -569,6 +569,7 @@ bgp_send_open(struct bgp_conn *conn) conn->peer_gr_time = 0; conn->peer_gr_flags = 0; conn->peer_gr_aflags = 0; + conn->peer_ext_messages_support = 0; DBG("BGP: Sending open\n"); conn->sk->rx_hook = bgp_rx; @@ -733,8 +734,8 @@ bgp_connect(struct bgp_proto *p) /* Enter Connect state and start establishing c s->dport = p->cf->remote_port; s->iface = p->neigh ? p->neigh->iface : NULL; s->ttl = p->cf->ttl_security ? 255 : hops; - s->rbsize = BGP_RX_BUFFER_SIZE; - s->tbsize = BGP_TX_BUFFER_SIZE; + s->rbsize = p->cf->enable_extended_messages ? BGP_RX_BUFFER_EXT_SIZE : BGP_RX_BUFFER_SIZE; + s->tbsize = p->cf->enable_extended_messages ? BGP_TX_BUFFER_EXT_SIZE : BGP_TX_BUFFER_SIZE; s->tos = IP_PREC_INTERNET_CONTROL; s->password = p->cf->password; s->tx_hook = bgp_connected; @@ -843,6 +844,13 @@ bgp_incoming_connection(sock *sk, int dummy UNUSED) if (sk_set_min_ttl(sk, 256 - hops) < 0) goto err; + if (p->cf->enable_extended_messages) + { + sk->rbsize = BGP_RX_BUFFER_EXT_SIZE; + sk->tbsize = BGP_TX_BUFFER_EXT_SIZE; + sk_reallocate(sk); + } + bgp_setup_conn(p, &p->incoming_conn); bgp_setup_sk(&p->incoming_conn, sk); bgp_send_open(&p->incoming_conn); @@ -1518,21 +1526,23 @@ bgp_show_proto_info(struct proto *P) else if (P->proto_state == PS_UP) { cli_msg(-1006, " Neighbor ID: %R", p->remote_id); - cli_msg(-1006, " Neighbor caps: %s%s%s%s%s%s", + cli_msg(-1006, " Neighbor caps: %s%s%s%s%s%s%s", c->peer_refresh_support ? " refresh" : "", c->peer_enhanced_refresh_support ? " enhanced-refresh" : "", c->peer_gr_able ? " restart-able" : (c->peer_gr_aware ? " restart-aware" : ""), c->peer_as4_support ? " AS4" : "", (c->peer_add_path & ADD_PATH_RX) ? " add-path-rx" : "", - (c->peer_add_path & ADD_PATH_TX) ? " add-path-tx" : ""); - cli_msg(-1006, " Session: %s%s%s%s%s%s%s", + (c->peer_add_path & ADD_PATH_TX) ? " add-path-tx" : "", + c->peer_ext_messages_support ? " ext-messages" : ""); + cli_msg(-1006, " Session: %s%s%s%s%s%s%s%s", p->is_internal ? "internal" : "external", p->cf->multihop ? " multihop" : "", p->rr_client ? " route-reflector" : "", p->rs_client ? " route-server" : "", p->as4_session ? " AS4" : "", p->add_path_rx ? " add-path-rx" : "", - p->add_path_tx ? " add-path-tx" : ""); + p->add_path_tx ? " add-path-tx" : "", + p->ext_messages ? " ext-messages" : ""); cli_msg(-1006, " Source address: %I", p->source_addr); if (P->cf->in_limit) cli_msg(-1006, " Route limit: %d/%d", diff --git a/proto/bgp/bgp.h b/proto/bgp/bgp.h index b6e80fe5..274794f1 100644 --- a/proto/bgp/bgp.h +++ b/proto/bgp/bgp.h @@ -40,6 +40,7 @@ struct bgp_config { int capabilities; /* Enable capability handshake [RFC3392] */ int enable_refresh; /* Enable local support for route refresh [RFC2918] */ int enable_as4; /* Enable local support for 4B AS numbers [RFC4893] */ + int enable_extended_messages; /* Enable local support for extended messages [draft] */ u32 rr_cluster_id; /* Route reflector cluster ID, if different from local ID */ int rr_client; /* Whether neighbor is RR client of me */ int rs_client; /* Whether neighbor is RS client of me */ @@ -109,6 +110,7 @@ struct bgp_conn { u16 peer_gr_time; u8 peer_gr_flags; u8 peer_gr_aflags; + u8 peer_ext_messages_support; /* Peer supports extended message length [draft] */ unsigned hold_time, keepalive_time; /* Times calculated from my and neighbor's requirements */ }; @@ -121,6 +123,7 @@ struct bgp_proto { u8 as4_session; /* Session uses 4B AS numbers in AS_PATH (both sides support it) */ u8 add_path_rx; /* Session expects receive of ADD-PATH extended NLRI */ u8 add_path_tx; /* Session expects transmit of ADD-PATH extended NLRI */ + u8 ext_messages; /* Session allows to use extended messages (both sides support it) */ u32 local_id; /* BGP identifier of this router */ u32 remote_id; /* BGP identifier of the neighbor */ u32 rr_cluster_id; /* Route reflector cluster ID */ @@ -180,9 +183,15 @@ struct bgp_bucket { #define BGP_PORT 179 #define BGP_VERSION 4 #define BGP_HEADER_LENGTH 19 -#define BGP_MAX_PACKET_LENGTH 4096 +#define BGP_MAX_MESSAGE_LENGTH 4096 +#define BGP_MAX_EXT_MSG_LENGTH 65535 #define BGP_RX_BUFFER_SIZE 4096 -#define BGP_TX_BUFFER_SIZE BGP_MAX_PACKET_LENGTH +#define BGP_TX_BUFFER_SIZE 4096 +#define BGP_RX_BUFFER_EXT_SIZE 65535 +#define BGP_TX_BUFFER_EXT_SIZE 65535 + +static inline int bgp_max_packet_length(struct bgp_proto *p) +{ return p->ext_messages ? BGP_MAX_EXT_MSG_LENGTH : BGP_MAX_MESSAGE_LENGTH; } extern struct linpool *bgp_linpool; diff --git a/proto/bgp/config.Y b/proto/bgp/config.Y index 49afe5ae..85b93a6b 100644 --- a/proto/bgp/config.Y +++ b/proto/bgp/config.Y @@ -27,7 +27,7 @@ CF_KEYWORDS(BGP, LOCAL, NEIGHBOR, AS, HOLD, TIME, CONNECT, RETRY, INTERPRET, COMMUNITIES, BGP_ORIGINATOR_ID, 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) + CHECK, LINK, PORT, EXTENDED, MESSAGES) CF_GRAMMAR @@ -108,6 +108,7 @@ bgp_proto: | bgp_proto DISABLE AFTER ERROR bool ';' { BGP_CFG->disable_after_error = $5; } | bgp_proto ENABLE ROUTE REFRESH bool ';' { BGP_CFG->enable_refresh = $5; } | bgp_proto ENABLE AS4 bool ';' { BGP_CFG->enable_as4 = $4; } + | bgp_proto ENABLE EXTENDED MESSAGES bool ';' { BGP_CFG->enable_extended_messages = $5; } | bgp_proto CAPABILITIES bool ';' { BGP_CFG->capabilities = $3; } | bgp_proto ADVERTISE IPV4 bool ';' { BGP_CFG->advertise_ipv4 = $4; } | bgp_proto PASSWORD text ';' { BGP_CFG->password = $3; } diff --git a/proto/bgp/packets.c b/proto/bgp/packets.c index 378f5ab1..ed99f623 100644 --- a/proto/bgp/packets.c +++ b/proto/bgp/packets.c @@ -84,7 +84,7 @@ mrt_put_bgp4_hdr(byte *buf, struct bgp_conn *conn, int as4) static void mrt_dump_bgp_packet(struct bgp_conn *conn, byte *pkt, unsigned len) { - byte buf[BGP_MAX_PACKET_LENGTH + 128]; + byte *buf = alloca(128+len); /* 128 is enough for MRT headers */ byte *bp = buf + MRTDUMP_HDR_LENGTH; int as4 = conn->bgp->as4_session; @@ -223,6 +223,14 @@ bgp_put_cap_err(struct bgp_proto *p UNUSED, byte *buf) return buf; } +static byte * +bgp_put_cap_ext_msg(struct bgp_proto *p UNUSED, byte *buf) +{ + *buf++ = 230; /* Capability TBD: Support for extended messages */ + *buf++ = 0; /* Capability data length */ + return buf; +} + static byte * bgp_create_open(struct bgp_conn *conn, byte *buf) @@ -274,6 +282,9 @@ bgp_create_open(struct bgp_conn *conn, byte *buf) if (p->cf->enable_refresh) cap = bgp_put_cap_err(p, cap); + if (p->cf->enable_extended_messages) + cap = bgp_put_cap_ext_msg(p, cap); + cap_len = cap - buf - 12; if (cap_len > 0) { @@ -342,7 +353,7 @@ bgp_create_update(struct bgp_conn *conn, byte *buf) { struct bgp_proto *p = conn->bgp; struct bgp_bucket *buck; - int remains = BGP_MAX_PACKET_LENGTH - BGP_HEADER_LENGTH - 4; + int remains = bgp_max_packet_length(p) - BGP_HEADER_LENGTH - 4; byte *w; int wd_size = 0; int r_size = 0; @@ -428,7 +439,7 @@ bgp_create_update(struct bgp_conn *conn, byte *buf) struct bgp_proto *p = conn->bgp; struct bgp_bucket *buck; int size, second, rem_stored; - int remains = BGP_MAX_PACKET_LENGTH - BGP_HEADER_LENGTH - 4; + int remains = bgp_max_packet_length(p) - BGP_HEADER_LENGTH - 4; byte *w, *w_stored, *tmp, *tstart; ip_addr *ipp, ip, ip_ll; ea_list *ea; @@ -856,6 +867,12 @@ bgp_parse_capabilities(struct bgp_conn *conn, byte *opt, int len) conn->peer_enhanced_refresh_support = 1; break; + case 230: /* Extended message length capability, draft, cap number TBD */ + if (cl != 0) + goto err; + conn->peer_ext_messages_support = 1; + break; + /* We can safely ignore all other capabilities */ } len -= 2 + cl; @@ -1019,6 +1036,7 @@ bgp_rx_open(struct bgp_conn *conn, byte *pkt, int len) p->add_path_rx = (p->cf->add_path & ADD_PATH_RX) && (conn->peer_add_path & ADD_PATH_TX); p->add_path_tx = (p->cf->add_path & ADD_PATH_TX) && (conn->peer_add_path & ADD_PATH_RX); p->gr_ready = p->cf->gr_mode && conn->peer_gr_able; + p->ext_messages = p->cf->enable_extended_messages && conn->peer_ext_messages_support; if (p->add_path_tx) p->p.accept_ra_types = RA_ANY; @@ -1418,7 +1436,7 @@ static struct { { 2, 4, "Unsupported optional parameter" }, { 2, 5, "Authentication failure" }, { 2, 6, "Unacceptable hold time" }, - { 2, 7, "Required capability missing" }, /* [RFC3392] */ + { 2, 7, "Required capability missing" }, /* [RFC5492] */ { 2, 8, "No supported AFI/SAFI" }, /* This error msg is nonstandard */ { 3, 0, "Invalid UPDATE message" }, { 3, 1, "Malformed attribute list" }, @@ -1666,6 +1684,7 @@ int bgp_rx(sock *sk, int size) { struct bgp_conn *conn = sk->data; + struct bgp_proto *p = conn->bgp; byte *pkt_start = sk->rbuf; byte *end = pkt_start + size; unsigned i, len; @@ -1682,7 +1701,7 @@ bgp_rx(sock *sk, int size) break; } len = get_u16(pkt_start+16); - if (len < BGP_HEADER_LENGTH || len > BGP_MAX_PACKET_LENGTH) + if (len < BGP_HEADER_LENGTH || len > bgp_max_packet_length(p)) { bgp_error(conn, 1, 2, pkt_start+16, 2); break; -- cgit v1.2.3