From 0b2aa3a0a8b095bdef1eddda117d173af75dede2 Mon Sep 17 00:00:00 2001 From: Paul Jakma Date: Sun, 14 Oct 2007 22:32:21 +0000 Subject: [bgpd] Merge AS4 support 2007-10-14 Paul Jakma * NEWS: Note that MRT dumps are now version 2 * (general) Merge in Juergen Kammer's AS4 patch. 2007-09-27 Paul Jakma * bgp_aspath.c: (assegment_normalise) remove duplicates from from sets. (aspath_reconcile_as4) disregard a broken part of the RFC around error handling in path reconciliation. * aspath_test.c: Test dupe-weeding from sets. Test that reconciliation merges AS_PATH and AS4_PATH where former is shorter than latter. 2007-09-26 Paul Jakma * aspath_test.c: Test AS4_PATH reconcilation where length of AS_PATH and AS4_PATH is same. 2007-09-25 Paul Jakma * bgp_open.c: (peek_for_as4_capability) Fix to work. * bgp_packet.c: (bgp_open_receive) Fix sanity check of as4. * tests/bgp_capability_test.c: (general) Extend tests to validate peek_for_as4_capability. Add test of full OPEN Option block, with multiple capabilities, both as a series of Option, and a single option. Add some crap to beginning of stream, to prevent code depending on getp == 0. 2007-09-18 Paul Jakma * bgp_open.c: (bgp_capability_as4) debug printf inline with others. (peek_for_as4_capability) There's no need to signal failure, as failure is better dealt with through full capability parser - just return the AS4, simpler. * bgp_packet.c: (bgp_open_receive) Update to match peek_for_as4_capability change. Allow use of BGP_AS_TRANS by 2b speakers. Use NOTIFY_OPEN_ERR rather than CEASE for OPEN parsing errors. (bgp_capability_msg_parse) missing argument to debug print (bgp_capability_receive) missing return values. * tests/bgp_capability_test.c: (parse_test) update for changes to peek_for_as4_capability 2007-07-25 Paul Jakma * Remove 2-byte size macros, just make existing macros take argument to indicate which size to use. Adjust all users - typically they want '1'. * bgp_aspath.c: (aspath_has_as4) New, return 1 if there are any as4's in a path. (aspath_put) Return the number of bytes actually written, to fix the bug Juergen noted: Splitting of segments will change the number of bytes written from that already written to the AS_PATH header. (aspath_snmp_pathseg) Pass 2-byte flag to aspath_put. SNMP is still defined as 2b. (aspath_aggregate) fix latent bug. (aspath_reconcile_as4) AS_PATH+NEW_AS_PATH reconciliation function. (aspath_key_make) Hash the AS_PATH string, rather than just taking the addition of assegment ASes as the hash value, hopefully sligthly more collision resistant. (bgp_attr_munge_as4_attrs) Collide the NEW_ attributes together with the OLD 2-byte forms, code Juergen had in bgp_attr_parse but re-organised a bit. (bgp_attr_parse) Bunch of code from Juergen moves to previous function. (bgp_packet_attribute) Compact significantly by just /always/ using extended-length attr header. Fix bug Juergen noted, by using aspath_put's (new) returned size value for the attr header rather than the (guesstimate) of aspath_size() - the two could differ when aspath_put had to split large segments, unlikely this bug was ever hit in the 'wild'. (bgp_dump_routes_attr) Always use extended-len and use aspath_put return for header length. Output 4b ASN for AS_PATH and AGGREGATOR. * bgp_ecommunity.c: (ecommunity_{hash_make,cmp}) fix hash callback declarations to match prototypes. (ecommunity_gettoken) Updated for ECOMMUNITY_ENCODE_AS4, complete rewrite of Juergen's changes (no asdot support) * bgp_open.c: (bgp_capability_as4) New, does what it says on the tin. (peek_for_as4_capability) Rewritten to use streams and bgp_capability_as4. * bgp_packet.c: (bgp_open_send) minor edit checked (in the abstract at least) with Juergen. Changes are to be more accepting, e.g, allow AS_TRANS on a 2-byte session. * (general) Update all commands to use CMD_AS_RANGE. * bgp_vty.c: (bgp_clear) Fix return vals to use CMD_.. Remove stuff replicated by VTY_GET_LONG (bgp_clear_vty) Return bgp_clear directly to vty. * tests/aspath_test.c: Exercise 32bit parsing. Test reconcile function. * tests/ecommunity_test.c: New, test AS4 ecommunity changes, positive test only at this time, error cases not tested yet. 2007-07-25 Juergen Kammer * (general) AS4 support. * bgpd.h: as_t changes to 4-bytes. * bgp_aspath.h: Add BGP_AS4_MAX and BGP_AS_TRANS defines. * bgp_aspath.c: AS_VALUE_SIZE becomes 4-byte, AS16_VALUE_SIZE added for 2-byte. Add AS16 versions of length calc macros. (aspath_count_numas) New, count number of ASes. (aspath_has_as4) New, return 1 if there are any as4's in a path. (assegments_parse) Interpret assegment as 4 or 2 byte, according to how the caller instructs us, with a new argument. (aspath_parse) Add use32bit argument to pass to assegments_parse. Adjust all its callers to pass 1, unless otherwise noted. (assegment_data_put) Adjust to be able to write 2 or 4 byte AS, according to new use32bit argument. (aspath_put) Adjust to write 2 or 4. (aspath_gettoken) Use a long for passed in asno. * bgp_attr.c: (attr_str) Add BGP_ATTR_AS4_PATH and BGP_ATTR_AS4_AGGREGATOR. (bgp_attr_aspath) Call aspath_parse with right 2/4 arg, as determined by received-capability flag. (bgp_attr_aspath_check) New, code previously in attr_aspath but moved to new func so it can be run after NEW_AS_PATH reconciliation. (bgp_attr_as4_path) New, handle NEW_AS_PATH. (bgp_attr_aggregator) Adjust to cope with 2/4 byte ASes. (bgp_attr_as4_aggregator) New, read NEW_AGGREGATOR. (bgp_attr_parse) Add handoffs to previous parsers for the two new AS4 NEW_ attributes. Various checks added for NEW/OLD reconciliation. (bgp_packet_attribute) Support 2/4 for AS_PATH and AGGREGATOR, detect when NEW_ attrs need to be sent. * bgp_debug.{c,h}: Add 'debug bgp as4'. * bgp_dump.c: MRTv2 support, unconditionally enabled, which supports AS4. Based on patches from Erik (RIPE?). * bgp_ecommunity.c: (ecommunity_ecom2str) ECOMMUNITY_ENCODE_AS4 support. * bgp_open.c: (peek_for_as4_capability) New, peek for AS4 capability prior to full capability parsing, so we know which ASN to use for struct peer lookup. (bgp_open_capability) Always send AS4 capability. * bgp_packet.c: (bgp_open_send) AS4 handling for AS field (bgp_open_receive) Peek for AS4 capability first, and figure out which AS to believe. * bgp_vty.c: (bgp_show_peer) Print AS4 cap * tests/aspath_test.c: Support asn32 changes, call aspath_parse with 16 bit. * vtysh/extract.pl: AS4 compatibility for router bgp ASNUMBER * vtysh/extract.pl.in: AS4 compatibility for router bgp ASNUMBER * vtysh/vtysh.c: AS4 compatibility for router bgp ASNUMBER --- bgpd/bgp_packet.c | 88 +++++++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 76 insertions(+), 12 deletions(-) (limited to 'bgpd/bgp_packet.c') diff --git a/bgpd/bgp_packet.c b/bgpd/bgp_packet.c index 17ac1f73..1fa2fdfd 100644 --- a/bgpd/bgp_packet.c +++ b/bgpd/bgp_packet.c @@ -804,7 +804,8 @@ bgp_open_send (struct peer *peer) /* Set open packet values. */ stream_putc (s, BGP_VERSION_4); /* BGP version */ - stream_putw (s, local_as); /* My Autonomous System*/ + stream_putw (s, (local_as <= BGP_AS_MAX) ? (u_int16_t) local_as + : BGP_AS_TRANS); stream_putw (s, send_holdtime); /* Hold Time */ stream_put_in_addr (s, &peer->local_id); /* BGP Identifier */ @@ -1168,6 +1169,7 @@ bgp_open_receive (struct peer *peer, bgp_size_t size) u_int16_t holdtime; u_int16_t send_holdtime; as_t remote_as; + as_t as4 = 0; struct peer *realpeer; struct in_addr remote_id; int capability; @@ -1186,10 +1188,75 @@ bgp_open_receive (struct peer *peer, bgp_size_t size) /* Receive OPEN message log */ if (BGP_DEBUG (normal, NORMAL)) - zlog_debug ("%s rcv OPEN, version %d, remote-as %d, holdtime %d, id %s", - peer->host, version, remote_as, holdtime, - inet_ntoa (remote_id)); - + zlog_debug ("%s rcv OPEN, version %d, remote-as (in open) %d," + " holdtime %d, id %s", + peer->host, version, remote_as, holdtime, + inet_ntoa (remote_id)); + + /* BEGIN to read the capability here, but dont do it yet */ + capability = 0; + optlen = stream_getc (peer->ibuf); + + if (optlen != 0) + { + /* We need the as4 capability value *right now* because + * if it is there, we have not got the remote_as yet, and without + * that we do not know which peer is connecting to us now. + */ + as4 = peek_for_as4_capability (peer, optlen); + } + + /* Just in case we have a silly peer who sends AS4 capability set to 0 */ + if (CHECK_FLAG (peer->cap, PEER_CAP_AS4_RCV) && !as4) + { + zlog_err ("%s bad OPEN, got AS4 capability, but AS4 set to 0", + peer->host); + bgp_notify_send (peer, BGP_NOTIFY_OPEN_ERR, + BGP_NOTIFY_OPEN_BAD_PEER_AS); + return -1; + } + + if (remote_as == BGP_AS_TRANS) + { + /* Take the AS4 from the capability. We must have received the + * capability now! Otherwise we have a asn16 peer who uses + * BGP_AS_TRANS, for some unknown reason. + */ + if (as4 == BGP_AS_TRANS) + { + zlog_err ("%s [AS4] NEW speaker using AS_TRANS for AS4, not allowed", + peer->host); + bgp_notify_send (peer, BGP_NOTIFY_OPEN_ERR, + BGP_NOTIFY_OPEN_BAD_PEER_AS); + return -1; + } + + if (!as4 && BGP_DEBUG (as4, AS4)) + zlog_debug ("%s [AS4] OPEN remote_as is AS_TRANS, but no AS4." + " Odd, but proceeding.", peer->host); + else if (as4 < BGP_AS_MAX && BGP_DEBUG (as4, AS4)) + zlog_debug ("%s [AS4] OPEN remote_as is AS_TRANS, but AS4 fits " + "in 2-bytes, very odd peer.", peer->host, as4); + if (as4) + remote_as = as4; + } + else + { + /* We may have a partner with AS4 who has an asno < BGP_AS_MAX */ + /* If we have got the capability, peer->as4cap must match remote_as */ + if (CHECK_FLAG (peer->cap, PEER_CAP_AS4_RCV) + && as4 != remote_as) + { + /* raise error, log this, close session */ + zlog_err ("%s bad OPEN, got AS4 capability, but remote_as %u" + " mismatch with 16bit 'myasn' %u in open", + peer->host, as4, remote_as); + bgp_notify_send (peer, BGP_NOTIFY_OPEN_ERR, + BGP_NOTIFY_OPEN_BAD_PEER_AS); + return -1; + } + } + /* Lookup peer from Open packet. */ if (CHECK_FLAG (peer->sflags, PEER_STATUS_ACCEPT_PEER)) { @@ -1364,8 +1431,6 @@ bgp_open_receive (struct peer *peer, bgp_size_t size) peer->v_keepalive = peer->v_holdtime / 3; /* Open option part parse. */ - capability = 0; - optlen = stream_getc (peer->ibuf); if (optlen != 0) { ret = bgp_open_option_parse (peer, optlen, &capability); @@ -2049,8 +2114,8 @@ bgp_capability_msg_parse (struct peer *peer, u_char *pnt, bgp_size_t length) if (!bgp_afi_safi_valid_indices (afi, &safi)) { if (BGP_DEBUG (normal, NORMAL)) - zlog_debug ("%s Dynamic Capability MP_EXT afi/safi invalid", - peer->host, afi, safi); + zlog_debug ("%s Dynamic Capability MP_EXT afi/safi invalid " + "(%u/%u)", peer->host, afi, safi); continue; } @@ -2097,7 +2162,6 @@ int bgp_capability_receive (struct peer *peer, bgp_size_t size) { u_char *pnt; - int ret; /* Fetch pointer. */ pnt = stream_pnt (peer->ibuf); @@ -2113,7 +2177,7 @@ bgp_capability_receive (struct peer *peer, bgp_size_t size) bgp_notify_send (peer, BGP_NOTIFY_HEADER_ERR, BGP_NOTIFY_HEADER_BAD_MESTYPE); - return; + return -1; } /* Status must be Established. */ @@ -2122,7 +2186,7 @@ bgp_capability_receive (struct peer *peer, bgp_size_t size) plog_err (peer->log, "%s [Error] Dynamic capability packet received under status %s", peer->host, LOOKUP (bgp_status_msg, peer->status)); bgp_notify_send (peer, BGP_NOTIFY_FSM_ERR, 0); - return; + return -1; } /* Parse packet. */ -- cgit v1.2.1