/* * Copyright (C) 1999 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * Extensively modified by Hannes Gredler (hannes@gredler.at) for more * complete BGP support. */ /* \summary: Border Gateway Protocol (BGP) printer */ /* specification: RFC 4271 */ #ifdef HAVE_CONFIG_H #include #endif #include "netdissect-stdinc.h" #include #include #include "netdissect.h" #include "addrtoname.h" #include "extract.h" #include "af.h" #include "l2vpn.h" struct bgp { nd_byte bgp_marker[16]; nd_uint16_t bgp_len; nd_uint8_t bgp_type; }; #define BGP_SIZE 19 /* unaligned */ #define BGP_OPEN 1 #define BGP_UPDATE 2 #define BGP_NOTIFICATION 3 #define BGP_KEEPALIVE 4 #define BGP_ROUTE_REFRESH 5 static const struct tok bgp_msg_values[] = { { BGP_OPEN, "Open"}, { BGP_UPDATE, "Update"}, { BGP_NOTIFICATION, "Notification"}, { BGP_KEEPALIVE, "Keepalive"}, { BGP_ROUTE_REFRESH, "Route Refresh"}, { 0, NULL} }; struct bgp_open { nd_byte bgpo_marker[16]; nd_uint16_t bgpo_len; nd_uint8_t bgpo_type; nd_uint8_t bgpo_version; nd_uint16_t bgpo_myas; nd_uint16_t bgpo_holdtime; nd_uint32_t bgpo_id; nd_uint8_t bgpo_optlen; nd_uint8_t bgpo_opttype; /* RFC9072 */ nd_uint16_t bgpo_optlen_extended; /* RFC9072 */ /* options should follow */ }; #define BGP_OPEN_SIZE 29 /* unaligned */ struct bgp_opt { nd_uint8_t bgpopt_type; nd_uint16_t bgpopt_len; /* Can be one or two bytes, depending on RFC9072 */ /* variable length */ }; #define BGP_OPT_SIZE 2 /* some compilers may pad to 4 bytes */ #define BGP_CAP_HEADER_SIZE 2 /* some compilers may pad to 4 bytes */ struct bgp_notification { nd_byte bgpn_marker[16]; nd_uint16_t bgpn_len; nd_uint8_t bgpn_type; nd_uint8_t bgpn_major; nd_uint8_t bgpn_minor; }; #define BGP_NOTIFICATION_SIZE 21 /* unaligned */ struct bgp_route_refresh_orf { nd_uint8_t refresh; nd_uint8_t type; nd_uint16_t len; }; struct bgp_route_refresh { nd_byte bgp_marker[16]; nd_uint16_t len; nd_uint8_t type; /* No padding after this; afi is, in fact, not aligned */ nd_uint16_t afi; nd_uint8_t subtype; nd_uint8_t safi; }; static const struct tok bgp_orf_refresh_type[] = { { 1, "Immediate"}, { 2, "Defer"}, { 0, NULL } }; static const struct tok bgp_orf_type[] = { { 64, "Address Prefix ORF"}, { 65, "CP-ORF"}, { 0, NULL } }; #define BGP_ROUTE_REFRESH_SIZE 23 #define BGP_ROUTE_REFRESH_SIZE_ORF BGP_ROUTE_REFRESH_SIZE + 5 #define BGP_ROUTE_REFRESH_SUBTYPE_NORMAL 0 #define BGP_ROUTE_REFRESH_SUBTYPE_BORR 1 #define BGP_ROUTE_REFRESH_SUBTYPE_EORR 2 #define BGP_ROUTE_REFRESH_SUBTYPE_RESERVED 255 static const struct tok bgp_route_refresh_subtype_values[] = { {BGP_ROUTE_REFRESH_SUBTYPE_NORMAL, "Normal route refresh request"}, {BGP_ROUTE_REFRESH_SUBTYPE_BORR, "Demarcation of the beginning of a route refresh"}, {BGP_ROUTE_REFRESH_SUBTYPE_EORR, "Demarcation of the ending of a route refresh"}, {0, NULL}}; #define bgp_attr_lenlen(flags, p) \ (((flags) & 0x10) ? 2U : 1U) #define bgp_attr_len(flags, p) \ (((flags) & 0x10) ? GET_BE_U_2(p) : GET_U_1(p)) #define BGPTYPE_ORIGIN 1 #define BGPTYPE_AS_PATH 2 #define BGPTYPE_NEXT_HOP 3 #define BGPTYPE_MULTI_EXIT_DISC 4 #define BGPTYPE_LOCAL_PREF 5 #define BGPTYPE_ATOMIC_AGGREGATE 6 #define BGPTYPE_AGGREGATOR 7 #define BGPTYPE_COMMUNITIES 8 /* RFC1997 */ #define BGPTYPE_ORIGINATOR_ID 9 /* RFC4456 */ #define BGPTYPE_CLUSTER_LIST 10 /* RFC4456 */ #define BGPTYPE_MP_REACH_NLRI 14 /* RFC4760 */ #define BGPTYPE_MP_UNREACH_NLRI 15 /* RFC4760 */ #define BGPTYPE_EXTD_COMMUNITIES 16 /* RFC4360 */ #define BGPTYPE_AS4_PATH 17 /* RFC6793 */ #define BGPTYPE_AGGREGATOR4 18 /* RFC6793 */ #define BGPTYPE_PMSI_TUNNEL 22 /* RFC6514 */ #define BGPTYPE_TUNNEL_ENCAP 23 /* RFC5512 */ #define BGPTYPE_TRAFFIC_ENG 24 /* RFC5543 */ #define BGPTYPE_IPV6_EXTD_COMMUNITIES 25 /* RFC5701 */ #define BGPTYPE_AIGP 26 /* RFC7311 */ #define BGPTYPE_PE_DISTINGUISHER_LABEL 27 /* RFC6514 */ #define BGPTYPE_ENTROPY_LABEL 28 /* RFC6790 */ #define BGPTYPE_LARGE_COMMUNITY 32 /* draft-ietf-idr-large-community-05 */ #define BGPTYPE_BGPSEC_PATH 33 /* RFC8205 */ #define BGPTYPE_OTC 35 /* RFC9234 */ #define BGPTYPE_ATTR_SET 128 /* RFC6368 */ #define BGP_MP_NLRI_MINSIZE 3 /* End of RIB Marker detection */ static const struct tok bgp_attr_values[] = { { BGPTYPE_ORIGIN, "Origin"}, { BGPTYPE_AS_PATH, "AS Path"}, { BGPTYPE_AS4_PATH, "AS4 Path"}, { BGPTYPE_NEXT_HOP, "Next Hop"}, { BGPTYPE_MULTI_EXIT_DISC, "Multi Exit Discriminator"}, { BGPTYPE_LOCAL_PREF, "Local Preference"}, { BGPTYPE_ATOMIC_AGGREGATE, "Atomic Aggregate"}, { BGPTYPE_AGGREGATOR, "Aggregator"}, { BGPTYPE_AGGREGATOR4, "Aggregator4"}, { BGPTYPE_COMMUNITIES, "Community"}, { BGPTYPE_ORIGINATOR_ID, "Originator ID"}, { BGPTYPE_CLUSTER_LIST, "Cluster List"}, { BGPTYPE_MP_REACH_NLRI, "Multi-Protocol Reach NLRI"}, { BGPTYPE_MP_UNREACH_NLRI, "Multi-Protocol Unreach NLRI"}, { BGPTYPE_EXTD_COMMUNITIES, "Extended Community"}, { BGPTYPE_PMSI_TUNNEL, "PMSI Tunnel"}, { BGPTYPE_TUNNEL_ENCAP, "Tunnel Encapsulation"}, { BGPTYPE_TRAFFIC_ENG, "Traffic Engineering"}, { BGPTYPE_IPV6_EXTD_COMMUNITIES, "IPv6 Extended Community"}, { BGPTYPE_AIGP, "Accumulated IGP Metric"}, { BGPTYPE_PE_DISTINGUISHER_LABEL, "PE Distinguisher Label"}, { BGPTYPE_ENTROPY_LABEL, "Entropy Label"}, { BGPTYPE_LARGE_COMMUNITY, "Large Community"}, { BGPTYPE_BGPSEC_PATH, "BGPsec Path"}, { BGPTYPE_OTC, "Only to Customer (OTC)"}, { BGPTYPE_ATTR_SET, "Attribute Set"}, { 255, "Reserved for development"}, { 0, NULL} }; #define BGP_AS_SET 1 #define BGP_AS_SEQUENCE 2 #define BGP_CONFED_AS_SEQUENCE 3 /* draft-ietf-idr-rfc3065bis-01 */ #define BGP_CONFED_AS_SET 4 /* draft-ietf-idr-rfc3065bis-01 */ #define BGP_AS_SEG_TYPE_MIN BGP_AS_SET #define BGP_AS_SEG_TYPE_MAX BGP_CONFED_AS_SET static const struct tok bgp_as_path_segment_open_values[] = { { BGP_AS_SEQUENCE, ""}, { BGP_AS_SET, "{ "}, { BGP_CONFED_AS_SEQUENCE, "( "}, { BGP_CONFED_AS_SET, "({ "}, { 0, NULL} }; static const struct tok bgp_as_path_segment_close_values[] = { { BGP_AS_SEQUENCE, ""}, { BGP_AS_SET, "}"}, { BGP_CONFED_AS_SEQUENCE, ")"}, { BGP_CONFED_AS_SET, "})"}, { 0, NULL} }; #define BGP_OPT_AUTH 1 #define BGP_OPT_CAP 2 static const struct tok bgp_opt_values[] = { { BGP_OPT_AUTH, "Authentication Information"}, { BGP_OPT_CAP, "Capabilities Advertisement"}, { 0, NULL} }; #define BGP_CAPCODE_MP 1 /* RFC2858 */ #define BGP_CAPCODE_RR 2 /* RFC2918 */ #define BGP_CAPCODE_ORF 3 /* RFC5291 */ #define BGP_CAPCODE_MR 4 /* RFC3107 */ #define BGP_CAPCODE_EXT_NH 5 /* RFC5549 */ #define BGP_CAPCODE_EXT_MSG 6 /* RFC8654 */ #define BGP_CAPCODE_BGPSEC 7 /* RFC8205 */ #define BGP_CAPCODE_ML 8 /* RFC8277 */ #define BGP_CAPCODE_ROLE 9 /* RFC9234 */ #define BGP_CAPCODE_RESTART 64 /* RFC4724 */ #define BGP_CAPCODE_AS_NEW 65 /* RFC6793 */ #define BGP_CAPCODE_DYN_CAP 67 /* draft-ietf-idr-dynamic-cap */ #define BGP_CAPCODE_MULTISESS 68 /* draft-ietf-idr-bgp-multisession */ #define BGP_CAPCODE_ADD_PATH 69 /* RFC7911 */ #define BGP_CAPCODE_ENH_RR 70 /* RFC7313 */ #define BGP_CAPCODE_LLGR 71 /* draft-uttaro-idr-bgp-persistence-05 */ #define BGP_CAPCODE_RR_CISCO 128 static const struct tok bgp_capcode_values[] = { { BGP_CAPCODE_MP, "Multiprotocol Extensions"}, { BGP_CAPCODE_RR, "Route Refresh"}, { BGP_CAPCODE_ORF, "Cooperative Route Filtering"}, { BGP_CAPCODE_MR, "Multiple Routes to a Destination"}, { BGP_CAPCODE_EXT_NH, "Extended Next Hop Encoding"}, { BGP_CAPCODE_EXT_MSG, "BGP Extended Message"}, { BGP_CAPCODE_BGPSEC, "BGPsec"}, { BGP_CAPCODE_ML, "Multiple Labels"}, { BGP_CAPCODE_RESTART, "Graceful Restart"}, { BGP_CAPCODE_AS_NEW, "32-Bit AS Number"}, { BGP_CAPCODE_DYN_CAP, "Dynamic Capability"}, { BGP_CAPCODE_MULTISESS, "Multisession BGP"}, { BGP_CAPCODE_ADD_PATH, "Multiple Paths"}, { BGP_CAPCODE_ENH_RR, "Enhanced Route Refresh"}, { BGP_CAPCODE_LLGR, "Long-lived Graceful Restart"}, { BGP_CAPCODE_RR_CISCO, "Route Refresh (Cisco)"}, { BGP_CAPCODE_ROLE, "Role Capability"}, { 0, NULL} }; #define BGP_NOTIFY_MAJOR_MSG 1 #define BGP_NOTIFY_MAJOR_OPEN 2 #define BGP_NOTIFY_MAJOR_UPDATE 3 #define BGP_NOTIFY_MAJOR_HOLDTIME 4 #define BGP_NOTIFY_MAJOR_FSM 5 #define BGP_NOTIFY_MAJOR_CEASE 6 #define BGP_NOTIFY_MAJOR_CAP 7 static const struct tok bgp_notify_major_values[] = { { BGP_NOTIFY_MAJOR_MSG, "Message Header Error"}, { BGP_NOTIFY_MAJOR_OPEN, "OPEN Message Error"}, { BGP_NOTIFY_MAJOR_UPDATE, "UPDATE Message Error"}, { BGP_NOTIFY_MAJOR_HOLDTIME,"Hold Timer Expired"}, { BGP_NOTIFY_MAJOR_FSM, "Finite State Machine Error"}, { BGP_NOTIFY_MAJOR_CEASE, "Cease"}, { BGP_NOTIFY_MAJOR_CAP, "Capability Message Error"}, { 0, NULL} }; /* RFC 4486 */ #define BGP_NOTIFY_MINOR_CEASE_MAXPRFX 1 /* RFC 9003 */ #define BGP_NOTIFY_MINOR_CEASE_SHUT 2 #define BGP_NOTIFY_MINOR_CEASE_RESET 4 /* RFC 8538 */ #define BGP_NOTIFY_MINOR_CEASE_HARDRESET 9 static const struct tok bgp_notify_minor_cease_values[] = { { BGP_NOTIFY_MINOR_CEASE_MAXPRFX, "Maximum Number of Prefixes Reached"}, { BGP_NOTIFY_MINOR_CEASE_SHUT, "Administrative Shutdown"}, { 3, "Peer Unconfigured"}, { BGP_NOTIFY_MINOR_CEASE_RESET, "Administrative Reset"}, { 5, "Connection Rejected"}, { 6, "Other Configuration Change"}, { 7, "Connection Collision Resolution"}, { 8, "Out of Resources"}, { BGP_NOTIFY_MINOR_CEASE_HARDRESET, "Hard Reset"}, { 10, "BFD Down"}, { 0, NULL} }; static const struct tok bgp_notify_minor_msg_values[] = { { 1, "Connection Not Synchronized"}, { 2, "Bad Message Length"}, { 3, "Bad Message Type"}, { 0, NULL} }; static const struct tok bgp_notify_minor_open_values[] = { { 1, "Unsupported Version Number"}, { 2, "Bad Peer AS"}, { 3, "Bad BGP Identifier"}, { 4, "Unsupported Optional Parameter"}, { 5, "Authentication Failure"}, { 6, "Unacceptable Hold Time"}, { 7, "Capability Message Error"}, { 0, NULL} }; static const struct tok bgp_notify_minor_update_values[] = { { 1, "Malformed Attribute List"}, { 2, "Unrecognized Well-known Attribute"}, { 3, "Missing Well-known Attribute"}, { 4, "Attribute Flags Error"}, { 5, "Attribute Length Error"}, { 6, "Invalid ORIGIN Attribute"}, { 7, "AS Routing Loop"}, { 8, "Invalid NEXT_HOP Attribute"}, { 9, "Optional Attribute Error"}, { 10, "Invalid Network Field"}, { 11, "Malformed AS_PATH"}, { 0, NULL} }; static const struct tok bgp_notify_minor_fsm_values[] = { { 0, "Unspecified Error"}, { 1, "In OpenSent State"}, { 2, "In OpenConfirm State"}, { 3, "In Established State"}, { 0, NULL } }; static const struct tok bgp_notify_minor_cap_values[] = { { 1, "Invalid Action Value" }, { 2, "Invalid Capability Length" }, { 3, "Malformed Capability Value" }, { 4, "Unsupported Capability Code" }, { 0, NULL } }; static const struct tok bgp_origin_values[] = { { 0, "IGP"}, { 1, "EGP"}, { 2, "Incomplete"}, { 0, NULL} }; #define BGP_PMSI_TUNNEL_RSVP_P2MP 1 #define BGP_PMSI_TUNNEL_LDP_P2MP 2 #define BGP_PMSI_TUNNEL_PIM_SSM 3 #define BGP_PMSI_TUNNEL_PIM_SM 4 #define BGP_PMSI_TUNNEL_PIM_BIDIR 5 #define BGP_PMSI_TUNNEL_INGRESS 6 #define BGP_PMSI_TUNNEL_LDP_MP2MP 7 static const struct tok bgp_pmsi_tunnel_values[] = { { BGP_PMSI_TUNNEL_RSVP_P2MP, "RSVP-TE P2MP LSP"}, { BGP_PMSI_TUNNEL_LDP_P2MP, "LDP P2MP LSP"}, { BGP_PMSI_TUNNEL_PIM_SSM, "PIM-SSM Tree"}, { BGP_PMSI_TUNNEL_PIM_SM, "PIM-SM Tree"}, { BGP_PMSI_TUNNEL_PIM_BIDIR, "PIM-Bidir Tree"}, { BGP_PMSI_TUNNEL_INGRESS, "Ingress Replication"}, { BGP_PMSI_TUNNEL_LDP_MP2MP, "LDP MP2MP LSP"}, { 0, NULL} }; static const struct tok bgp_pmsi_flag_values[] = { { 0x01, "Leaf Information required"}, { 0, NULL} }; #define BGP_AIGP_TLV 1 static const struct tok bgp_aigp_values[] = { { BGP_AIGP_TLV, "AIGP"}, { 0, NULL} }; #define BGP_ROLE_PROVIDER 0 #define BGP_ROLE_RS 1 #define BGP_ROLE_RS_CLIENT 2 #define BGP_ROLE_CUSTOMER 3 #define BGP_ROLE_PEER 4 static const struct tok bgp_role_values[] = { { BGP_ROLE_PROVIDER, "Provider"}, { BGP_ROLE_RS, "RS"}, { BGP_ROLE_RS_CLIENT, "RS-Client"}, { BGP_ROLE_CUSTOMER, "Customer"}, { BGP_ROLE_PEER, "Peer"}, { 0, NULL} }; /* Subsequent address family identifier, RFC2283 section 7 */ #define SAFNUM_RES 0 #define SAFNUM_UNICAST 1 #define SAFNUM_MULTICAST 2 #define SAFNUM_UNIMULTICAST 3 /* deprecated now */ /* labeled BGP RFC3107 */ #define SAFNUM_LABUNICAST 4 /* RFC6514 */ #define SAFNUM_MULTICAST_VPN 5 /* draft-nalawade-kapoor-tunnel-safi */ #define SAFNUM_TUNNEL 64 /* RFC4761 */ #define SAFNUM_VPLS 65 /* RFC6037 */ #define SAFNUM_MDT 66 /* RFC7432 */ #define SAFNUM_EVPN 70 /* RFC4364 */ #define SAFNUM_VPNUNICAST 128 /* RFC6513 */ #define SAFNUM_VPNMULTICAST 129 #define SAFNUM_VPNUNIMULTICAST 130 /* deprecated now */ /* RFC4684 */ #define SAFNUM_RT_ROUTING_INFO 132 #define BGP_VPN_RD_LEN 8 static const struct tok bgp_safi_values[] = { { SAFNUM_RES, "Reserved"}, { SAFNUM_UNICAST, "Unicast"}, { SAFNUM_MULTICAST, "Multicast"}, { SAFNUM_UNIMULTICAST, "Unicast+Multicast"}, { SAFNUM_LABUNICAST, "labeled Unicast"}, { SAFNUM_TUNNEL, "Tunnel"}, { SAFNUM_VPLS, "VPLS"}, { SAFNUM_MDT, "MDT"}, { SAFNUM_EVPN, "EVPN"}, { SAFNUM_VPNUNICAST, "labeled VPN Unicast"}, { SAFNUM_VPNMULTICAST, "labeled VPN Multicast"}, { SAFNUM_VPNUNIMULTICAST, "labeled VPN Unicast+Multicast"}, { SAFNUM_RT_ROUTING_INFO, "Route Target Routing Information"}, { SAFNUM_MULTICAST_VPN, "Multicast VPN"}, { 0, NULL } }; static const struct tok bgp_graceful_restart_comm_flag_values[] = { { 0x8, "R" }, { 0x4, "N" }, { 0, NULL } }; /* well-known community */ #define BGP_COMMUNITY_NO_EXPORT 0xffffff01 #define BGP_COMMUNITY_NO_ADVERT 0xffffff02 #define BGP_COMMUNITY_NO_EXPORT_SUBCONFED 0xffffff03 /* Extended community type - RFC 4360 */ #define BGP_EXT_COM_RT_0 0x0002 /* Route Target,Format AS(2bytes):AN(4bytes) */ #define BGP_EXT_COM_RT_1 0x0102 /* Route Target,Format IP address:AN(2bytes) */ #define BGP_EXT_COM_RT_2 0x0202 /* Route Target,Format AN(4bytes):local(2bytes) */ #define BGP_EXT_COM_RO_0 0x0003 /* Route Origin,Format AS(2bytes):AN(4bytes) */ #define BGP_EXT_COM_RO_1 0x0103 /* Route Origin,Format IP address:AN(2bytes) */ #define BGP_EXT_COM_RO_2 0x0203 /* Route Origin,Format AN(4bytes):local(2bytes) */ #define BGP_EXT_COM_LINKBAND 0x4004 /* Link Bandwidth,Format AS(2B):Bandwidth(4B) */ #define BGP_EXT_COM_OVS 0x4300 /* BGP Prefix Origin Validation State Extended Community */ /* rfc2547 bgp-mpls-vpns */ #define BGP_EXT_COM_VPN_ORIGIN 0x0005 /* OSPF Domain ID / VPN of Origin - draft-rosen-vpns-ospf-bgp-mpls */ #define BGP_EXT_COM_VPN_ORIGIN2 0x0105 /* duplicate - keep for backwards compatibility */ #define BGP_EXT_COM_VPN_ORIGIN3 0x0205 /* duplicate - keep for backwards compatibility */ #define BGP_EXT_COM_VPN_ORIGIN4 0x8005 /* duplicate - keep for backwards compatibility */ #define BGP_EXT_COM_OSPF_RTYPE 0x0306 /* OSPF Route Type,Format Area(4B):RouteType(1B):Options(1B) */ #define BGP_EXT_COM_OSPF_RTYPE2 0x8000 /* duplicate - keep for backwards compatibility */ #define BGP_EXT_COM_ENCAP 0x030c /* rfc5512 */ #define BGP_EXT_COM_OSPF_RID 0x0107 /* OSPF Router ID,Format RouterID(4B):Unused(2B) */ #define BGP_EXT_COM_OSPF_RID2 0x8001 /* duplicate - keep for backwards compatibility */ #define BGP_EXT_COM_L2INFO 0x800a /* draft-kompella-ppvpn-l2vpn */ #define BGP_EXT_COM_SOURCE_AS 0x0009 /* RFC-ietf-l3vpn-2547bis-mcast-bgp-08.txt */ #define BGP_EXT_COM_VRF_RT_IMP 0x010b /* RFC-ietf-l3vpn-2547bis-mcast-bgp-08.txt */ #define BGP_EXT_COM_L2VPN_RT_0 0x000a /* L2VPN Identifier,Format AS(2bytes):AN(4bytes) */ #define BGP_EXT_COM_L2VPN_RT_1 0xF10a /* L2VPN Identifier,Format IP address:AN(2bytes) */ /* https://www.cisco.com/en/US/tech/tk436/tk428/technologies_tech_note09186a00801eb09a.shtml */ #define BGP_EXT_COM_EIGRP_GEN 0x8800 #define BGP_EXT_COM_EIGRP_METRIC_AS_DELAY 0x8801 #define BGP_EXT_COM_EIGRP_METRIC_REL_NH_BW 0x8802 #define BGP_EXT_COM_EIGRP_METRIC_LOAD_MTU 0x8803 #define BGP_EXT_COM_EIGRP_EXT_REMAS_REMID 0x8804 #define BGP_EXT_COM_EIGRP_EXT_REMPROTO_REMMETRIC 0x8805 /* Optional Parameters */ #define BGP_OPEN_NON_EXT_OPT_TYPE_EXTENDED_LENGTH 255 /* Non-Ext OP Type */ static const struct tok bgp_extd_comm_flag_values[] = { { 0x8000, "vendor-specific"}, { 0x4000, "non-transitive"}, { 0, NULL}, }; /* rfc8097 */ static const struct tok bgp_prefix_origin_validation_state[] = { { 0, "valid" }, { 1, "not found" }, { 2, "invalid" }, { 0, NULL }, }; static const struct tok bgp_extd_comm_subtype_values[] = { { BGP_EXT_COM_RT_0, "target"}, { BGP_EXT_COM_RT_1, "target"}, { BGP_EXT_COM_RT_2, "target"}, { BGP_EXT_COM_RO_0, "origin"}, { BGP_EXT_COM_RO_1, "origin"}, { BGP_EXT_COM_RO_2, "origin"}, { BGP_EXT_COM_LINKBAND, "link-BW"}, { BGP_EXT_COM_OVS, "origin-validation-state"}, { BGP_EXT_COM_VPN_ORIGIN, "ospf-domain"}, { BGP_EXT_COM_VPN_ORIGIN2, "ospf-domain"}, { BGP_EXT_COM_VPN_ORIGIN3, "ospf-domain"}, { BGP_EXT_COM_VPN_ORIGIN4, "ospf-domain"}, { BGP_EXT_COM_OSPF_RTYPE, "ospf-route-type"}, { BGP_EXT_COM_OSPF_RTYPE2, "ospf-route-type"}, { BGP_EXT_COM_ENCAP, "encapsulation"}, { BGP_EXT_COM_OSPF_RID, "ospf-router-id"}, { BGP_EXT_COM_OSPF_RID2, "ospf-router-id"}, { BGP_EXT_COM_L2INFO, "layer2-info"}, { BGP_EXT_COM_EIGRP_GEN, "eigrp-general-route (flag, tag)" }, { BGP_EXT_COM_EIGRP_METRIC_AS_DELAY, "eigrp-route-metric (AS, delay)" }, { BGP_EXT_COM_EIGRP_METRIC_REL_NH_BW, "eigrp-route-metric (reliability, nexthop, bandwidth)" }, { BGP_EXT_COM_EIGRP_METRIC_LOAD_MTU, "eigrp-route-metric (load, MTU)" }, { BGP_EXT_COM_EIGRP_EXT_REMAS_REMID, "eigrp-external-route (remote-AS, remote-ID)" }, { BGP_EXT_COM_EIGRP_EXT_REMPROTO_REMMETRIC, "eigrp-external-route (remote-proto, remote-metric)" }, { BGP_EXT_COM_SOURCE_AS, "source-AS" }, { BGP_EXT_COM_VRF_RT_IMP, "vrf-route-import"}, { BGP_EXT_COM_L2VPN_RT_0, "l2vpn-id"}, { BGP_EXT_COM_L2VPN_RT_1, "l2vpn-id"}, { 0, NULL}, }; /* RFC RFC5512 BGP Tunnel Encapsulation Attribute Tunnel Types */ #define BGP_ENCAP_TUNNEL_L2TPV3_IP 1 #define BGP_ENCAP_TUNNEL_GRE 2 #define BGP_ENCAP_TUNNEL_TRANSMIT 3 #define BGP_ENCAP_TUNNEL_IPSEC 4 #define BGP_ENCAP_TUNNEL_IP_IPSEC 5 #define BGP_ENCAP_TUNNEL_MPLS_IP 6 #define BGP_ENCAP_TUNNEL_IP_IP 7 #define BGP_ENCAP_TUNNEL_VXLAN 8 #define BGP_ENCAP_TUNNEL_NVGRE 9 #define BGP_ENCAP_TUNNEL_MPLS 10 #define BGP_ENCAP_TUNNEL_MPLS_GRE 11 #define BGP_ENCAP_TUNNEL_VXLAN_GPE 12 #define BGP_ENCAP_TUNNEL_MPLS_UDP 13 #define BGP_ENCAP_TUNNEL_IPV6 14 #define BGP_ENCAP_TUNNEL_SR_TE 15 #define BGP_ENCAP_TUNNEL_BARE 16 #define BGP_ENCAP_TUNNEL_SR 17 static const struct tok bgp_extd_comm_encap_tunnel_values[] = { { BGP_ENCAP_TUNNEL_L2TPV3_IP, "L2TPv3 over IP"}, { BGP_ENCAP_TUNNEL_GRE, "GRE"}, { BGP_ENCAP_TUNNEL_TRANSMIT, "Transmit Tunnel"}, { BGP_ENCAP_TUNNEL_IPSEC, "IPsec"}, { BGP_ENCAP_TUNNEL_IP_IPSEC, "IP in IP with IPsec"}, { BGP_ENCAP_TUNNEL_MPLS_IP, "MPLS in IP with IPsec"}, { BGP_ENCAP_TUNNEL_IP_IP, "IP in IP"}, { BGP_ENCAP_TUNNEL_VXLAN, "VXLAN"}, { BGP_ENCAP_TUNNEL_NVGRE, "NVGRE"}, { BGP_ENCAP_TUNNEL_MPLS, "MPLS"}, { BGP_ENCAP_TUNNEL_MPLS_GRE, "MPLS in GRE"}, { BGP_ENCAP_TUNNEL_VXLAN_GPE, "VXLAN GPE"}, { BGP_ENCAP_TUNNEL_MPLS_UDP, "MPLS in UDP"}, { BGP_ENCAP_TUNNEL_IPV6, "IPv6"}, { BGP_ENCAP_TUNNEL_SR_TE, "SR TE"}, { BGP_ENCAP_TUNNEL_BARE, "Bare"}, { BGP_ENCAP_TUNNEL_SR, "SR"}, { 0, NULL}, }; /* OSPF codes for BGP_EXT_COM_OSPF_RTYPE draft-rosen-vpns-ospf-bgp-mpls */ #define BGP_OSPF_RTYPE_RTR 1 /* OSPF Router LSA */ #define BGP_OSPF_RTYPE_NET 2 /* OSPF Network LSA */ #define BGP_OSPF_RTYPE_SUM 3 /* OSPF Summary LSA */ #define BGP_OSPF_RTYPE_EXT 5 /* OSPF External LSA, note that ASBR doesn't apply to MPLS-VPN */ #define BGP_OSPF_RTYPE_NSSA 7 /* OSPF NSSA External*/ #define BGP_OSPF_RTYPE_SHAM 129 /* OSPF-MPLS-VPN Sham link */ #define BGP_OSPF_RTYPE_METRIC_TYPE 0x1 /* LSB of RTYPE Options Field */ static const struct tok bgp_extd_comm_ospf_rtype_values[] = { { BGP_OSPF_RTYPE_RTR, "Router" }, { BGP_OSPF_RTYPE_NET, "Network" }, { BGP_OSPF_RTYPE_SUM, "Summary" }, { BGP_OSPF_RTYPE_EXT, "External" }, { BGP_OSPF_RTYPE_NSSA,"NSSA External" }, { BGP_OSPF_RTYPE_SHAM,"MPLS-VPN Sham" }, { 0, NULL }, }; /* ADD-PATH Send/Receive field values */ static const struct tok bgp_add_path_recvsend[] = { { 1, "Receive" }, { 2, "Send" }, { 3, "Both" }, { 0, NULL }, }; static const struct tok bgp_bgpsec_bitmap_str[] = { { 1U << 0, "MBZ-0" }, { 1U << 1, "MBZ-1" }, { 1U << 2, "MBZ-2" }, { 1U << 3, "MBZ-3" }, { 1U << 4, "MBZ-4" }, { 1U << 5, "MBZ-5" }, { 1U << 6, "MBZ-6" }, { 1U << 7, "C" }, { 0, NULL} }; #define AS_STR_SIZE sizeof("xxxxx.xxxxx") /* * as_printf * * Convert an AS number into a string and return string pointer. * * Depending on bflag is set or not, AS number is converted into ASDOT notation * or plain number notation. * */ static char * as_printf(netdissect_options *ndo, char *str, size_t size, u_int asnum) { if (!ndo->ndo_bflag || asnum <= 0xFFFF) { snprintf(str, size, "%u", asnum); } else { snprintf(str, size, "%u.%u", asnum >> 16, asnum & 0xFFFF); } return str; } #define ITEMCHECK(minlen) if (itemlen < minlen) goto badtlv; int decode_prefix4(netdissect_options *ndo, const u_char *pptr, u_int itemlen, char *buf, size_t buflen) { nd_ipv4 addr; u_int plen, plenbytes; ITEMCHECK(1); plen = GET_U_1(pptr); if (32 < plen) return -1; itemlen -= 1; memset(&addr, 0, sizeof(addr)); plenbytes = (plen + 7) / 8; ITEMCHECK(plenbytes); GET_CPY_BYTES(&addr, pptr + 1, plenbytes); if (plen % 8) { ((u_char *)&addr)[plenbytes - 1] &= ((0xff00 >> (plen % 8)) & 0xff); } snprintf(buf, buflen, "%s/%u", ipaddr_string(ndo, (const u_char *)&addr), plen); return 1 + plenbytes; badtlv: return -2; } static int decode_labeled_prefix4(netdissect_options *ndo, const u_char *pptr, u_int itemlen, char *buf, size_t buflen) { nd_ipv4 addr; u_int plen, plenbytes; /* prefix length and label = 4 bytes */ ND_TCHECK_4(pptr); ITEMCHECK(4); plen = GET_U_1(pptr); /* get prefix length */ /* this is one of the weirdnesses of rfc3107 the label length (actually the label + COS bits) is added to the prefix length; we also do only read out just one label - there is no real application for advertisement of stacked labels in a single BGP message */ if (24 > plen) return -1; plen-=24; /* adjust prefixlen - labellength */ if (32 < plen) return -1; itemlen -= 4; memset(&addr, 0, sizeof(addr)); plenbytes = (plen + 7) / 8; ITEMCHECK(plenbytes); GET_CPY_BYTES(&addr, pptr + 4, plenbytes); if (plen % 8) { ((u_char *)&addr)[plenbytes - 1] &= ((0xff00 >> (plen % 8)) & 0xff); } /* the label may get offsetted by 4 bits so lets shift it right */ snprintf(buf, buflen, "%s/%u, label:%u %s", ipaddr_string(ndo, (const u_char *)&addr), plen, GET_BE_U_3(pptr + 1)>>4, ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" ); return 4 + plenbytes; trunc: return -2; badtlv: return -3; } /* * bgp_vpn_ip_print * * print an ipv4 or ipv6 address into a buffer dependent on address length. */ static char * bgp_vpn_ip_print(netdissect_options *ndo, const u_char *pptr, u_int addr_length) { /* worst case string is s fully formatted v6 address */ static char addr[sizeof("1234:5678:89ab:cdef:1234:5678:89ab:cdef")]; char *pos = addr; switch(addr_length) { case (sizeof(nd_ipv4) << 3): /* 32 */ snprintf(pos, sizeof(addr), "%s", GET_IPADDR_STRING(pptr)); break; case (sizeof(nd_ipv6) << 3): /* 128 */ snprintf(pos, sizeof(addr), "%s", GET_IP6ADDR_STRING(pptr)); break; default: snprintf(pos, sizeof(addr), "bogus address length %u", addr_length); break; } pos += strlen(pos); *(pos) = '\0'; return (addr); } /* * bgp_vpn_sg_print * * print an multicast s,g entry into a buffer. * the s,g entry is encoded like this. * * +-----------------------------------+ * | Multicast Source Length (1 octet) | * +-----------------------------------+ * | Multicast Source (Variable) | * +-----------------------------------+ * | Multicast Group Length (1 octet) | * +-----------------------------------+ * | Multicast Group (Variable) | * +-----------------------------------+ * * return the number of bytes read from the wire. */ static u_int bgp_vpn_sg_print(netdissect_options *ndo, const u_char *pptr, char *buf, size_t buflen) { uint8_t addr_length; u_int total_length, offset; total_length = 0; /* Source address length, encoded in bits */ addr_length = GET_U_1(pptr); pptr++; /* Source address */ ND_TCHECK_LEN(pptr, (addr_length >> 3)); total_length += (addr_length >> 3) + 1; offset = (u_int)strlen(buf); if (addr_length) { snprintf(buf + offset, buflen - offset, ", Source %s", bgp_vpn_ip_print(ndo, pptr, addr_length)); pptr += (addr_length >> 3); } /* Group address length, encoded in bits */ addr_length = GET_U_1(pptr); pptr++; /* Group address */ ND_TCHECK_LEN(pptr, (addr_length >> 3)); total_length += (addr_length >> 3) + 1; offset = (u_int)strlen(buf); if (addr_length) { snprintf(buf + offset, buflen - offset, ", Group %s", bgp_vpn_ip_print(ndo, pptr, addr_length)); pptr += (addr_length >> 3); } trunc: return (total_length); } /* Print an RFC 4364 Route Distinguisher */ const char * bgp_vpn_rd_print(netdissect_options *ndo, const u_char *pptr) { /* allocate space for the largest possible string */ static char rd[sizeof("xxxxx.xxxxx:xxxxx (xxx.xxx.xxx.xxx:xxxxx)")]; char *pos = rd; /* allocate space for the largest possible string */ char astostr[AS_STR_SIZE]; /* ok lets load the RD format */ switch (GET_BE_U_2(pptr)) { case 0: /* 2-byte-AS:number fmt */ snprintf(pos, sizeof(rd) - (pos - rd), "%u:%u (= %u.%u.%u.%u)", GET_BE_U_2(pptr + 2), GET_BE_U_4(pptr + 4), GET_U_1(pptr + 4), GET_U_1(pptr + 5), GET_U_1(pptr + 6), GET_U_1(pptr + 7)); break; case 1: /* IP-address:AS fmt */ snprintf(pos, sizeof(rd) - (pos - rd), "%u.%u.%u.%u:%u", GET_U_1(pptr + 2), GET_U_1(pptr + 3), GET_U_1(pptr + 4), GET_U_1(pptr + 5), GET_BE_U_2(pptr + 6)); break; case 2: /* 4-byte-AS:number fmt */ snprintf(pos, sizeof(rd) - (pos - rd), "%s:%u (%u.%u.%u.%u:%u)", as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(pptr + 2)), GET_BE_U_2(pptr + 6), GET_U_1(pptr + 2), GET_U_1(pptr + 3), GET_U_1(pptr + 4), GET_U_1(pptr + 5), GET_BE_U_2(pptr + 6)); break; default: snprintf(pos, sizeof(rd) - (pos - rd), "unknown RD format"); break; } pos += strlen(pos); *(pos) = '\0'; return (rd); } /* * Print an RFC 4360 Extended Community. */ static void bgp_extended_community_print(netdissect_options *ndo, const u_char *pptr) { union { /* copy buffer for bandwidth values */ float f; uint32_t i; } bw; /* allocate space for the largest possible string */ char astostr[AS_STR_SIZE]; switch (GET_BE_U_2(pptr)) { case BGP_EXT_COM_RT_0: case BGP_EXT_COM_RO_0: case BGP_EXT_COM_L2VPN_RT_0: ND_PRINT("%u:%u (= %s)", GET_BE_U_2(pptr + 2), GET_BE_U_4(pptr + 4), GET_IPADDR_STRING(pptr+4)); break; case BGP_EXT_COM_RT_1: case BGP_EXT_COM_RO_1: case BGP_EXT_COM_L2VPN_RT_1: case BGP_EXT_COM_VRF_RT_IMP: ND_PRINT("%s:%u", GET_IPADDR_STRING(pptr+2), GET_BE_U_2(pptr + 6)); break; case BGP_EXT_COM_RT_2: case BGP_EXT_COM_RO_2: ND_PRINT("%s:%u", as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(pptr + 2)), GET_BE_U_2(pptr + 6)); break; case BGP_EXT_COM_LINKBAND: bw.i = GET_BE_U_4(pptr + 4); ND_PRINT("bandwidth: %.3f Mbps", bw.f*8/1000000); break; case BGP_EXT_COM_OVS: /* The Reserved field MUST be set to 0 and ignored upon the * receipt of this community. */ { uint64_t reserved = GET_BE_U_5(pptr + 2); if (reserved) ND_PRINT("[the reserved field 0x%" PRIx64 " MUST be 0] ", reserved); ND_PRINT("ovs: %s", tok2str(bgp_prefix_origin_validation_state, "unknown origin validation state", GET_U_1(pptr + 7))); } break; case BGP_EXT_COM_VPN_ORIGIN: case BGP_EXT_COM_VPN_ORIGIN2: case BGP_EXT_COM_VPN_ORIGIN3: case BGP_EXT_COM_VPN_ORIGIN4: case BGP_EXT_COM_OSPF_RID: case BGP_EXT_COM_OSPF_RID2: ND_PRINT("%s", GET_IPADDR_STRING(pptr+2)); break; case BGP_EXT_COM_OSPF_RTYPE: case BGP_EXT_COM_OSPF_RTYPE2: ND_PRINT("area:%s, router-type:%s, metric-type:%s%s", GET_IPADDR_STRING(pptr+2), tok2str(bgp_extd_comm_ospf_rtype_values, "unknown (0x%02x)", GET_U_1((pptr + 6))), (GET_U_1(pptr + 7) & BGP_OSPF_RTYPE_METRIC_TYPE) ? "E2" : "", ((GET_U_1(pptr + 6) == BGP_OSPF_RTYPE_EXT) || (GET_U_1(pptr + 6) == BGP_OSPF_RTYPE_NSSA)) ? "E1" : ""); break; case BGP_EXT_COM_L2INFO: ND_PRINT("%s Control Flags [0x%02x]:MTU %u", tok2str(l2vpn_encaps_values, "unknown encaps", GET_U_1((pptr + 2))), GET_U_1((pptr + 3)), GET_BE_U_2(pptr + 4)); break; case BGP_EXT_COM_SOURCE_AS: ND_PRINT("AS %u", GET_BE_U_2(pptr + 2)); break; case BGP_EXT_COM_ENCAP: ND_PRINT("Tunnel type: %s", tok2str(bgp_extd_comm_encap_tunnel_values, "unknown encaps", GET_BE_U_2(pptr + 6))); break; default: ND_PRINT("%02x%02x%02x%02x%02x%02x", GET_U_1(pptr + 2), GET_U_1(pptr + 3), GET_U_1(pptr + 4), GET_U_1(pptr + 5), GET_U_1(pptr + 6), GET_U_1(pptr + 7)); break; } } /* * RFC4684 (Section 4)/RFC2858 (Section 4). * RTC membership prefix is structured as follows * [prefix-len] [origin-as] [route-target] * The route-target is encoded as RT ext-comms. * Prefix-len may be 0, 32..96 * * Note that pptr is not packet data - it is * a buffer owned by our caller - therefore GET_* * macros can not be used. */ static char * bgp_rt_prefix_print(netdissect_options *ndo, const u_char *pptr, u_int plen) { /* allocate space for the largest possible string */ char rtc_prefix_in_hex[sizeof("0000 0000 0000 0000")] = ""; u_int rtc_prefix_in_hex_len = 0; static char output[61]; /* max response string */ /* allocate space for the largest possible string */ char astostr[AS_STR_SIZE]; uint16_t ec_type = 0; u_int octet_count; u_int i; if (plen == 0) { snprintf(output, sizeof(output), "route-target: 0:0/0"); return (output); } /* hex representation of the prefix */ octet_count = (plen+7)/8; for (i=0; i plen) { ND_PRINT("\n\t (illegal prefix length)"); return -1; } /* With at least "origin AS", possibly with "route target". */ as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(pptr + 1)); plen -= 32; /* adjust prefix length */ if (64 < plen) { ND_PRINT("\n\t (illegal prefix length)"); return -1; } /* From now on (plen + 7) / 8 evaluates to { 0, 1, 2, ..., 8 } * and gives the number of octets in the variable-length "route * target" field inside this NLRI "prefix". Look for it. */ memset(&route_target, 0, sizeof(route_target)); num_octets = (plen + 7) / 8; GET_CPY_BYTES(&route_target, pptr + 5, num_octets); /* If mask-len is not on octet boundary, ensure all extra bits are 0 */ if (plen % 8) { ((u_char *)&route_target)[num_octets - 1] &= ((0xff00 >> (plen % 8)) & 0xff); } ND_PRINT("\n\t origin AS: %s, %s", astostr, bgp_rt_prefix_print(ndo, (u_char *)&route_target, plen)); return 5 + num_octets; } static int decode_labeled_vpn_prefix4(netdissect_options *ndo, const u_char *pptr, char *buf, size_t buflen) { nd_ipv4 addr; u_int plen; plen = GET_U_1(pptr); /* get prefix length */ if ((24+64) > plen) return -1; plen -= (24+64); /* adjust prefixlen - labellength - RD len*/ if (32 < plen) return -1; memset(&addr, 0, sizeof(addr)); GET_CPY_BYTES(&addr, pptr + 12, (plen + 7) / 8); if (plen % 8) { ((u_char *)&addr)[(plen + 7) / 8 - 1] &= ((0xff00 >> (plen % 8)) & 0xff); } /* the label may get offsetted by 4 bits so lets shift it right */ snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s", bgp_vpn_rd_print(ndo, pptr+4), ipaddr_string(ndo, (const u_char *)&addr), plen, GET_BE_U_3(pptr + 1)>>4, ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" ); return 12 + (plen + 7) / 8; } /* * +-------------------------------+ * | | * | RD:IPv4-address (12 octets) | * | | * +-------------------------------+ * | MDT Group-address (4 octets) | * +-------------------------------+ */ #define MDT_VPN_NLRI_LEN 16 static int decode_mdt_vpn_nlri(netdissect_options *ndo, const u_char *pptr, char *buf, size_t buflen) { const u_char *rd; const u_char *vpn_ip; /* if the NLRI is not predefined length, quit.*/ if (GET_U_1(pptr) != MDT_VPN_NLRI_LEN * 8) return -1; pptr++; /* RD */ ND_TCHECK_8(pptr); rd = pptr; pptr += 8; /* IPv4 address */ vpn_ip = pptr; pptr += sizeof(nd_ipv4); /* MDT Group Address */ snprintf(buf, buflen, "RD: %s, VPN IP Address: %s, MC Group Address: %s", bgp_vpn_rd_print(ndo, rd), GET_IPADDR_STRING(vpn_ip), GET_IPADDR_STRING(pptr)); return MDT_VPN_NLRI_LEN + 1; trunc: return -2; } #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI 1 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI 2 #define BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI 3 #define BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF 4 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE 5 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN 6 #define BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN 7 static const struct tok bgp_multicast_vpn_route_type_values[] = { { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI, "Intra-AS I-PMSI"}, { BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI, "Inter-AS I-PMSI"}, { BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI, "S-PMSI"}, { BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF, "Intra-AS Segment-Leaf"}, { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE, "Source-Active"}, { BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN, "Shared Tree Join"}, { BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN, "Source Tree Join"}, { 0, NULL} }; static int decode_multicast_vpn(netdissect_options *ndo, const u_char *pptr, char *buf, size_t buflen) { /* allocate space for the largest possible string */ char astostr[AS_STR_SIZE]; uint8_t route_type, route_length; u_int addr_length, sg_length; u_int offset; route_type = GET_U_1(pptr); pptr++; route_length = GET_U_1(pptr); pptr++; snprintf(buf, buflen, "Route-Type: %s (%u), length: %u", tok2str(bgp_multicast_vpn_route_type_values, "Unknown", route_type), route_type, route_length); switch(route_type) { case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_I_PMSI: ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN); offset = (u_int)strlen(buf); snprintf(buf + offset, buflen - offset, ", RD: %s, Originator %s", bgp_vpn_rd_print(ndo, pptr), bgp_vpn_ip_print(ndo, pptr + BGP_VPN_RD_LEN, (route_length - BGP_VPN_RD_LEN) << 3)); break; case BGP_MULTICAST_VPN_ROUTE_TYPE_INTER_AS_I_PMSI: ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN + 4); offset = (u_int)strlen(buf); snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %s", bgp_vpn_rd_print(ndo, pptr), as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(pptr + BGP_VPN_RD_LEN))); break; case BGP_MULTICAST_VPN_ROUTE_TYPE_S_PMSI: ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN); offset = (u_int)strlen(buf); snprintf(buf + offset, buflen - offset, ", RD: %s", bgp_vpn_rd_print(ndo, pptr)); pptr += BGP_VPN_RD_LEN; sg_length = bgp_vpn_sg_print(ndo, pptr, buf, buflen); addr_length = route_length - sg_length; ND_TCHECK_LEN(pptr, addr_length); offset = (u_int)strlen(buf); snprintf(buf + offset, buflen - offset, ", Originator %s", bgp_vpn_ip_print(ndo, pptr, addr_length << 3)); break; case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_ACTIVE: ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN); offset = (u_int)strlen(buf); snprintf(buf + offset, buflen - offset, ", RD: %s", bgp_vpn_rd_print(ndo, pptr)); pptr += BGP_VPN_RD_LEN; bgp_vpn_sg_print(ndo, pptr, buf, buflen); break; case BGP_MULTICAST_VPN_ROUTE_TYPE_SHARED_TREE_JOIN: /* fall through */ case BGP_MULTICAST_VPN_ROUTE_TYPE_SOURCE_TREE_JOIN: ND_TCHECK_LEN(pptr, BGP_VPN_RD_LEN + 4); offset = (u_int)strlen(buf); snprintf(buf + offset, buflen - offset, ", RD: %s, Source-AS %s", bgp_vpn_rd_print(ndo, pptr), as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(pptr + BGP_VPN_RD_LEN))); pptr += BGP_VPN_RD_LEN + 4; bgp_vpn_sg_print(ndo, pptr, buf, buflen); break; /* * no per route-type printing yet. */ case BGP_MULTICAST_VPN_ROUTE_TYPE_INTRA_AS_SEG_LEAF: default: break; } return route_length + 2; trunc: return -2; } /* * As I remember, some versions of systems have an snprintf() that * returns -1 if the buffer would have overflowed. If the return * value is negative, set buflen to 0, to indicate that we've filled * the buffer up. * * If the return value is greater than buflen, that means that * the buffer would have overflowed; again, set buflen to 0 in * that case. */ #define UPDATE_BUF_BUFLEN(buf, buflen, stringlen) \ if (stringlen<0) \ buflen=0; \ else if ((u_int)stringlen>buflen) \ buflen=0; \ else { \ buflen-=stringlen; \ buf+=stringlen; \ } static int decode_labeled_vpn_l2(netdissect_options *ndo, const u_char *pptr, char *buf, size_t buflen) { u_int plen, tlen, tlv_type, tlv_len, ttlv_len; int stringlen; plen = GET_BE_U_2(pptr); tlen = plen; pptr += 2; /* Old and new L2VPN NLRI share AFI/SAFI * -> Assume a 12 Byte-length NLRI is auto-discovery-only * and > 17 as old format. Complain for the middle case */ if (plen == 12) { /* assume AD-only with RD, BGPNH */ ND_TCHECK_LEN(pptr, 12); buf[0] = '\0'; stringlen = snprintf(buf, buflen, "RD: %s, BGPNH: %s", bgp_vpn_rd_print(ndo, pptr), GET_IPADDR_STRING(pptr+8)); UPDATE_BUF_BUFLEN(buf, buflen, stringlen); pptr += 12; tlen -= 12; return plen + 2; } else if (plen > 17) { /* assume old format */ /* RD, ID, LBLKOFF, LBLBASE */ ND_TCHECK_LEN(pptr, 15); buf[0] = '\0'; stringlen = snprintf(buf, buflen, "RD: %s, CE-ID: %u, Label-Block Offset: %u, Label Base %u", bgp_vpn_rd_print(ndo, pptr), GET_BE_U_2(pptr + 8), GET_BE_U_2(pptr + 10), GET_BE_U_3(pptr + 12)>>4); /* the label is offsetted by 4 bits so lets shift it right */ UPDATE_BUF_BUFLEN(buf, buflen, stringlen); pptr += 15; tlen -= 15; /* ok now the variable part - lets read out TLVs*/ while (tlen != 0) { if (tlen < 3) { if (buflen != 0) { stringlen=snprintf(buf,buflen, "\n\t\tran past the end"); UPDATE_BUF_BUFLEN(buf, buflen, stringlen); } return plen + 2; } tlv_type = GET_U_1(pptr); pptr++; tlv_len = GET_BE_U_2(pptr); /* length, in *bits* */ ttlv_len = (tlv_len + 7)/8; /* length, in *bytes* */ pptr += 2; switch(tlv_type) { case 1: if (buflen != 0) { stringlen=snprintf(buf,buflen, "\n\t\tcircuit status vector (%u) length: %u: 0x", tlv_type, tlv_len); UPDATE_BUF_BUFLEN(buf, buflen, stringlen); } while (ttlv_len != 0) { if (tlen < 1) { if (buflen != 0) { stringlen=snprintf(buf,buflen, " (ran past the end)"); UPDATE_BUF_BUFLEN(buf, buflen, stringlen); } return plen + 2; } ND_TCHECK_1(pptr); if (buflen != 0) { stringlen=snprintf(buf,buflen, "%02x", GET_U_1(pptr)); pptr++; UPDATE_BUF_BUFLEN(buf, buflen, stringlen); } ttlv_len--; tlen--; } break; default: if (buflen != 0) { stringlen=snprintf(buf,buflen, "\n\t\tunknown TLV #%u, length: %u", tlv_type, tlv_len); UPDATE_BUF_BUFLEN(buf, buflen, stringlen); } if (tlen < ttlv_len) { if (buflen != 0) { stringlen=snprintf(buf,buflen, " (ran past the end)"); UPDATE_BUF_BUFLEN(buf, buflen, stringlen); } return plen + 2; } tlen -= ttlv_len; break; } } return plen + 2; } else { /* complain bitterly ? */ /* fall through */ goto trunc; } trunc: return -2; } int decode_prefix6(netdissect_options *ndo, const u_char *pd, u_int itemlen, char *buf, size_t buflen) { nd_ipv6 addr; u_int plen, plenbytes; ITEMCHECK(1); plen = GET_U_1(pd); if (128 < plen) return -1; itemlen -= 1; memset(&addr, 0, sizeof(addr)); plenbytes = (plen + 7) / 8; ITEMCHECK(plenbytes); GET_CPY_BYTES(&addr, pd + 1, plenbytes); if (plen % 8) { addr[plenbytes - 1] &= ((0xff00 >> (plen % 8)) & 0xff); } snprintf(buf, buflen, "%s/%u", ip6addr_string(ndo, (const u_char *)&addr), plen); return 1 + plenbytes; badtlv: return -2; } static int decode_labeled_prefix6(netdissect_options *ndo, const u_char *pptr, u_int itemlen, char *buf, size_t buflen) { nd_ipv6 addr; u_int plen, plenbytes; /* prefix length and label = 4 bytes */ ND_TCHECK_4(pptr); ITEMCHECK(4); plen = GET_U_1(pptr); /* get prefix length */ if (24 > plen) return -1; plen -= 24; /* adjust prefixlen - labellength */ if (128 < plen) return -1; itemlen -= 4; memset(&addr, 0, sizeof(addr)); plenbytes = (plen + 7) / 8; GET_CPY_BYTES(&addr, pptr + 4, plenbytes); if (plen % 8) { addr[plenbytes - 1] &= ((0xff00 >> (plen % 8)) & 0xff); } /* the label may get offsetted by 4 bits so lets shift it right */ snprintf(buf, buflen, "%s/%u, label:%u %s", ip6addr_string(ndo, (const u_char *)&addr), plen, GET_BE_U_3(pptr + 1)>>4, ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" ); return 4 + plenbytes; trunc: return -2; badtlv: return -3; } static int decode_labeled_vpn_prefix6(netdissect_options *ndo, const u_char *pptr, char *buf, size_t buflen) { nd_ipv6 addr; u_int plen; plen = GET_U_1(pptr); /* get prefix length */ if ((24+64) > plen) return -1; plen -= (24+64); /* adjust prefixlen - labellength - RD len*/ if (128 < plen) return -1; memset(&addr, 0, sizeof(addr)); GET_CPY_BYTES(&addr, pptr + 12, (plen + 7) / 8); if (plen % 8) { addr[(plen + 7) / 8 - 1] &= ((0xff00 >> (plen % 8)) & 0xff); } /* the label may get offsetted by 4 bits so lets shift it right */ snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s", bgp_vpn_rd_print(ndo, pptr+4), ip6addr_string(ndo, (const u_char *)&addr), plen, GET_BE_U_3(pptr + 1)>>4, ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" ); return 12 + (plen + 7) / 8; } static int decode_clnp_prefix(netdissect_options *ndo, const u_char *pptr, char *buf, size_t buflen) { uint8_t addr[19]; u_int plen; plen = GET_U_1(pptr); /* get prefix length */ if (152 < plen) return -1; memset(&addr, 0, sizeof(addr)); GET_CPY_BYTES(&addr, pptr + 4, (plen + 7) / 8); if (plen % 8) { addr[(plen + 7) / 8 - 1] &= ((0xff00 >> (plen % 8)) & 0xff); } /* Cannot use GET_ISONSAP_STRING (not packet buffer pointer) */ snprintf(buf, buflen, "%s/%u", isonsap_string(ndo, addr,(plen + 7) / 8), plen); return 1 + (plen + 7) / 8; } static int decode_labeled_vpn_clnp_prefix(netdissect_options *ndo, const u_char *pptr, char *buf, size_t buflen) { uint8_t addr[19]; u_int plen; plen = GET_U_1(pptr); /* get prefix length */ if ((24+64) > plen) return -1; plen -= (24+64); /* adjust prefixlen - labellength - RD len*/ if (152 < plen) return -1; memset(&addr, 0, sizeof(addr)); GET_CPY_BYTES(&addr, pptr + 12, (plen + 7) / 8); if (plen % 8) { addr[(plen + 7) / 8 - 1] &= ((0xff00 >> (plen % 8)) & 0xff); } /* the label may get offsetted by 4 bits so lets shift it right */ /* Cannot use GET_ISONSAP_STRING (not packet buffer pointer) */ snprintf(buf, buflen, "RD: %s, %s/%u, label:%u %s", bgp_vpn_rd_print(ndo, pptr+4), isonsap_string(ndo, addr,(plen + 7) / 8), plen, GET_BE_U_3(pptr + 1)>>4, ((GET_U_1(pptr + 3) & 1) == 0) ? "(BOGUS: Bottom of Stack NOT set!)" : "(bottom)" ); return 12 + (plen + 7) / 8; } /* * bgp_attr_get_as_size * * Try to find the size of the ASs encoded in an as-path. It is not obvious, as * both Old speakers that do not support 4 byte AS, and the new speakers that do * support, exchange AS-Path with the same path-attribute type value 0x02. */ static u_int bgp_attr_get_as_size(netdissect_options *ndo, uint8_t bgpa_type, const u_char *pptr, u_int len) { const u_char *tptr = pptr; /* * If the path attribute is the optional AS4 path type, then we already * know, that ASs must be encoded in 4 byte format. */ if (bgpa_type == BGPTYPE_AS4_PATH) { return 4; } /* * Let us assume that ASs are of 2 bytes in size, and check if the AS-Path * TLV is good. If not, ask the caller to try with AS encoded as 4 bytes * each. */ while (tptr < pptr + len) { /* * If we do not find a valid segment type, our guess might be wrong. */ if (GET_U_1(tptr) < BGP_AS_SEG_TYPE_MIN || GET_U_1(tptr) > BGP_AS_SEG_TYPE_MAX) { goto trunc; } tptr += 2 + GET_U_1(tptr + 1) * 2; } /* * If we correctly reached end of the AS path attribute data content, * then most likely ASs were indeed encoded as 2 bytes. */ if (tptr == pptr + len) { return 2; } trunc: /* * We can come here, either we did not have enough data, or if we * try to decode 4 byte ASs in 2 byte format. Either way, return 4, * so that calller can try to decode each AS as of 4 bytes. If indeed * there was not enough data, it will crib and end the parse anyways. */ return 4; } /* * The only way to know that a BGP UPDATE message is using add path is * by checking if the capability is in the OPEN message which we may have missed. * So this function checks if it is possible that the update could contain add path * and if so it checks that standard BGP doesn't make sense. */ static int check_add_path(netdissect_options *ndo, const u_char *pptr, u_int length, u_int max_prefix_length) { u_int offset, prefix_length; if (length < 5) { return 0; } /* * Scan through the NLRI information under the assumpetion that * it doesn't have path IDs. */ for (offset = 0; offset < length;) { offset += 4; if (!ND_TTEST_1(pptr + offset)) { /* We ran out of captured data; quit scanning. */ break; } prefix_length = GET_U_1(pptr + offset); /* * Add 4 to cover the path id * and check the prefix length isn't greater than 32/128. */ if (prefix_length > max_prefix_length) { return 0; } /* Add 1 for the prefix_length byte and prefix_length to cover the address */ offset += 1 + ((prefix_length + 7) / 8); } /* check we haven't gone past the end of the section */ if (offset > length) { return 0; } /* check it's not standard BGP */ for (offset = 0; offset < length; ) { if (!ND_TTEST_1(pptr + offset)) { /* We ran out of captured data; quit scanning. */ break; } prefix_length = GET_U_1(pptr + offset); /* * If the prefix_length is zero (0.0.0.0/0) * and since it's not the only address (length >= 5) * then it is add-path */ if (prefix_length < 1 || prefix_length > max_prefix_length) { return 1; } offset += 1 + ((prefix_length + 7) / 8); } if (offset > length) { return 1; } /* assume not add-path by default */ return 0; } static int bgp_mp_af_print(netdissect_options *ndo, const u_char *tptr, u_int tlen, uint16_t *afp, uint8_t *safip) { uint16_t af; uint8_t safi; af = GET_BE_U_2(tptr); *afp = af; safi = GET_U_1(tptr + 2); *safip = safi; ND_PRINT("\n\t AFI: %s (%u), %sSAFI: %s (%u)", tok2str(af_values, "Unknown AFI", af), af, (safi>128) ? "vendor specific " : "", /* 128 is meanwhile wellknown */ tok2str(bgp_safi_values, "Unknown SAFI", safi), safi); switch(af<<8 | safi) { case (AFNUM_IP<<8 | SAFNUM_UNICAST): case (AFNUM_IP<<8 | SAFNUM_MULTICAST): case (AFNUM_IP<<8 | SAFNUM_UNIMULTICAST): case (AFNUM_IP<<8 | SAFNUM_LABUNICAST): case (AFNUM_IP<<8 | SAFNUM_RT_ROUTING_INFO): case (AFNUM_IP<<8 | SAFNUM_VPNUNICAST): case (AFNUM_IP<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_IP<<8 | SAFNUM_VPNUNIMULTICAST): case (AFNUM_IP<<8 | SAFNUM_MULTICAST_VPN): case (AFNUM_IP<<8 | SAFNUM_MDT): case (AFNUM_IP6<<8 | SAFNUM_UNICAST): case (AFNUM_IP6<<8 | SAFNUM_MULTICAST): case (AFNUM_IP6<<8 | SAFNUM_UNIMULTICAST): case (AFNUM_IP6<<8 | SAFNUM_LABUNICAST): case (AFNUM_IP6<<8 | SAFNUM_VPNUNICAST): case (AFNUM_IP6<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_IP6<<8 | SAFNUM_VPNUNIMULTICAST): case (AFNUM_NSAP<<8 | SAFNUM_UNICAST): case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST): case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST): case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST): case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST): case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST): case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST): case (AFNUM_VPLS<<8 | SAFNUM_VPLS): break; default: ND_TCHECK_LEN(tptr, tlen); ND_PRINT("\n\t no AFI %u / SAFI %u decoder", af, safi); if (ndo->ndo_vflag <= 1) print_unknown_data(ndo, tptr, "\n\t ", tlen); return -1; } return 0; trunc: return -2; } static int bgp_nlri_print(netdissect_options *ndo, uint16_t af, uint8_t safi, const u_char *tptr, u_int len, char *buf, size_t buflen, int add_path4, int add_path6) { int advance; u_int path_id = 0; switch (af<<8 | safi) { case (AFNUM_IP<<8 | SAFNUM_UNICAST): case (AFNUM_IP<<8 | SAFNUM_MULTICAST): case (AFNUM_IP<<8 | SAFNUM_UNIMULTICAST): if (add_path4) { path_id = GET_BE_U_4(tptr); tptr += 4; } advance = decode_prefix4(ndo, tptr, len, buf, buflen); if (advance == -1) ND_PRINT("\n\t (illegal prefix length)"); else if (advance == -2) break; /* bytes left, but not enough */ else ND_PRINT("\n\t %s", buf); if (add_path4) { ND_PRINT(" Path Id: %u", path_id); advance += 4; } break; case (AFNUM_IP<<8 | SAFNUM_LABUNICAST): advance = decode_labeled_prefix4(ndo, tptr, len, buf, buflen); if (advance == -1) ND_PRINT("\n\t (illegal prefix length)"); else if (advance == -2) goto trunc; else if (advance == -3) break; /* bytes left, but not enough */ else ND_PRINT("\n\t %s", buf); break; case (AFNUM_IP<<8 | SAFNUM_VPNUNICAST): case (AFNUM_IP<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_IP<<8 | SAFNUM_VPNUNIMULTICAST): advance = decode_labeled_vpn_prefix4(ndo, tptr, buf, buflen); if (advance == -1) ND_PRINT("\n\t (illegal prefix length)"); else ND_PRINT("\n\t %s", buf); break; case (AFNUM_IP<<8 | SAFNUM_RT_ROUTING_INFO): advance = decode_rt_routing_info(ndo, tptr); break; case (AFNUM_IP<<8 | SAFNUM_MULTICAST_VPN): /* fall through */ case (AFNUM_IP6<<8 | SAFNUM_MULTICAST_VPN): advance = decode_multicast_vpn(ndo, tptr, buf, buflen); if (advance == -1) ND_PRINT("\n\t (illegal prefix length)"); else if (advance == -2) goto trunc; else ND_PRINT("\n\t %s", buf); break; case (AFNUM_IP<<8 | SAFNUM_MDT): advance = decode_mdt_vpn_nlri(ndo, tptr, buf, buflen); if (advance == -1) ND_PRINT("\n\t (illegal prefix length)"); else if (advance == -2) goto trunc; else ND_PRINT("\n\t %s", buf); break; case (AFNUM_IP6<<8 | SAFNUM_UNICAST): case (AFNUM_IP6<<8 | SAFNUM_MULTICAST): case (AFNUM_IP6<<8 | SAFNUM_UNIMULTICAST): if (add_path6) { path_id = GET_BE_U_4(tptr); tptr += 4; } advance = decode_prefix6(ndo, tptr, len, buf, buflen); if (advance == -1) ND_PRINT("\n\t (illegal prefix length)"); else if (advance == -2) break; /* bytes left, but not enough */ else ND_PRINT("\n\t %s", buf); if (add_path6) { ND_PRINT(" Path Id: %u", path_id); advance += 4; } break; case (AFNUM_IP6<<8 | SAFNUM_LABUNICAST): advance = decode_labeled_prefix6(ndo, tptr, len, buf, buflen); if (advance == -1) ND_PRINT("\n\t (illegal prefix length)"); else if (advance == -2) goto trunc; else if (advance == -3) break; /* bytes left, but not enough */ else ND_PRINT("\n\t %s", buf); break; case (AFNUM_IP6<<8 | SAFNUM_VPNUNICAST): case (AFNUM_IP6<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_IP6<<8 | SAFNUM_VPNUNIMULTICAST): advance = decode_labeled_vpn_prefix6(ndo, tptr, buf, buflen); if (advance == -1) ND_PRINT("\n\t (illegal prefix length)"); else ND_PRINT("\n\t %s", buf); break; case (AFNUM_VPLS<<8 | SAFNUM_VPLS): case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST): case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST): advance = decode_labeled_vpn_l2(ndo, tptr, buf, buflen); if (advance == -1) ND_PRINT("\n\t (illegal length)"); else if (advance == -2) goto trunc; else ND_PRINT("\n\t %s", buf); break; case (AFNUM_NSAP<<8 | SAFNUM_UNICAST): case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST): case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST): advance = decode_clnp_prefix(ndo, tptr, buf, buflen); if (advance == -1) ND_PRINT("\n\t (illegal prefix length)"); else ND_PRINT("\n\t %s", buf); break; case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST): case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST): advance = decode_labeled_vpn_clnp_prefix(ndo, tptr, buf, buflen); if (advance == -1) ND_PRINT("\n\t (illegal prefix length)"); else ND_PRINT("\n\t %s", buf); break; default: /* * This should not happen, we should have been protected * by bgp_mp_af_print()'s return value. */ ND_PRINT("\n\t ERROR: no AFI %u / SAFI %u decoder", af, safi); advance = -4; break; } return advance; trunc: /* we rely on the caller to recognize -2 return value */ return -2; } static const struct tok bgp_flags[] = { { 0x80, "O"}, { 0x40, "T"}, { 0x20, "P"}, { 0x10, "E"}, { 0, NULL } }; static int bgp_attr_print(netdissect_options *ndo, uint8_t atype, const u_char *pptr, u_int len, const unsigned attr_set_level) { /* allocate space for the largest possible string */ char astostr[AS_STR_SIZE]; u_int i; uint16_t af; uint8_t safi, snpa, nhlen; int advance; u_int tlen; const u_char *tptr; char buf[MAXHOSTNAMELEN + 100]; u_int as_size; int add_path4, add_path6; int ret; tptr = pptr; tlen = len; switch (atype) { case BGPTYPE_ORIGIN: if (len != 1) ND_PRINT("invalid len"); else { ND_PRINT("%s", tok2str(bgp_origin_values, "Unknown Origin Typecode", GET_U_1(tptr))); } break; /* * Process AS4 byte path and AS2 byte path attributes here. */ case BGPTYPE_AS4_PATH: case BGPTYPE_AS_PATH: if (len % 2) { ND_PRINT("invalid len"); break; } if (!len) { ND_PRINT("empty"); break; } /* * BGP updates exchanged between New speakers that support 4 * byte AS, ASs are always encoded in 4 bytes. There is no * definitive way to find this, just by the packet's * contents. So, check for packet's TLV's sanity assuming * 2 bytes first, and it does not pass, assume that ASs are * encoded in 4 bytes format and move on. */ as_size = bgp_attr_get_as_size(ndo, atype, pptr, len); while (tptr < pptr + len) { ND_PRINT("%s", tok2str(bgp_as_path_segment_open_values, "?", GET_U_1(tptr))); for (i = 0; i < GET_U_1(tptr + 1) * as_size; i += as_size) { ND_TCHECK_LEN(tptr + 2 + i, as_size); ND_PRINT("%s ", as_printf(ndo, astostr, sizeof(astostr), as_size == 2 ? GET_BE_U_2(tptr + i + 2) : GET_BE_U_4(tptr + i + 2))); } ND_PRINT("%s", tok2str(bgp_as_path_segment_close_values, "?", GET_U_1(tptr))); tptr += 2 + GET_U_1(tptr + 1) * as_size; } break; case BGPTYPE_NEXT_HOP: if (len != 4) ND_PRINT("invalid len"); else { ND_PRINT("%s", GET_IPADDR_STRING(tptr)); } break; case BGPTYPE_MULTI_EXIT_DISC: case BGPTYPE_LOCAL_PREF: if (len != 4) ND_PRINT("invalid len"); else { ND_PRINT("%u", GET_BE_U_4(tptr)); } break; case BGPTYPE_ATOMIC_AGGREGATE: if (len != 0) ND_PRINT("invalid len"); break; case BGPTYPE_AGGREGATOR: /* * Depending on the AS encoded is of 2 bytes or of 4 bytes, * the length of this PA can be either 6 bytes or 8 bytes. */ if (len != 6 && len != 8) { ND_PRINT("invalid len"); break; } ND_TCHECK_LEN(tptr, len); if (len == 6) { ND_PRINT(" AS #%s, origin %s", as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_2(tptr)), GET_IPADDR_STRING(tptr + 2)); } else { ND_PRINT(" AS #%s, origin %s", as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)), GET_IPADDR_STRING(tptr + 4)); } break; case BGPTYPE_AGGREGATOR4: if (len != 8) { ND_PRINT("invalid len"); break; } ND_PRINT(" AS #%s, origin %s", as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr)), GET_IPADDR_STRING(tptr + 4)); break; case BGPTYPE_COMMUNITIES: if (len % 4) { ND_PRINT("invalid len"); break; } while (tlen != 0) { uint32_t comm; ND_TCHECK_4(tptr); if (tlen < 4) goto trunc; comm = GET_BE_U_4(tptr); switch (comm) { case BGP_COMMUNITY_NO_EXPORT: ND_PRINT(" NO_EXPORT"); break; case BGP_COMMUNITY_NO_ADVERT: ND_PRINT(" NO_ADVERTISE"); break; case BGP_COMMUNITY_NO_EXPORT_SUBCONFED: ND_PRINT(" NO_EXPORT_SUBCONFED"); break; default: ND_PRINT("%u:%u%s", (comm >> 16) & 0xffff, comm & 0xffff, (tlen>4) ? ", " : ""); break; } tlen -=4; tptr +=4; } break; case BGPTYPE_ORIGINATOR_ID: if (len != 4) { ND_PRINT("invalid len"); break; } ND_PRINT("%s",GET_IPADDR_STRING(tptr)); break; case BGPTYPE_CLUSTER_LIST: if (len % 4) { ND_PRINT("invalid len"); break; } while (tlen != 0) { if (tlen < 4) goto trunc; ND_PRINT("%s%s", GET_IPADDR_STRING(tptr), (tlen>4) ? ", " : ""); tlen -=4; tptr +=4; } break; case BGPTYPE_MP_REACH_NLRI: ND_TCHECK_3(tptr); if (tlen < 3) goto trunc; ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi); if (ret == -2) goto trunc; if (ret < 0) break; tptr += 3; tlen -= 3; ND_TCHECK_1(tptr); if (tlen < 1) goto trunc; nhlen = GET_U_1(tptr); tptr++; tlen--; if (nhlen) { u_int nnh = 0; uint8_t tnhlen = nhlen; if (tlen < tnhlen) goto trunc; ND_PRINT("\n\t nexthop: "); while (tnhlen != 0) { if (nnh++ > 0) { ND_PRINT(", " ); } switch(af<<8 | safi) { case (AFNUM_IP<<8 | SAFNUM_UNICAST): case (AFNUM_IP<<8 | SAFNUM_MULTICAST): case (AFNUM_IP<<8 | SAFNUM_UNIMULTICAST): case (AFNUM_IP<<8 | SAFNUM_LABUNICAST): case (AFNUM_IP<<8 | SAFNUM_RT_ROUTING_INFO): case (AFNUM_IP<<8 | SAFNUM_MULTICAST_VPN): case (AFNUM_IP<<8 | SAFNUM_MDT): if (tnhlen < sizeof(nd_ipv4)) { ND_PRINT("invalid len"); tptr += tnhlen; tlen -= tnhlen; tnhlen = 0; } else { ND_PRINT("%s",GET_IPADDR_STRING(tptr)); tptr += sizeof(nd_ipv4); tnhlen -= sizeof(nd_ipv4); tlen -= sizeof(nd_ipv4); } break; case (AFNUM_IP<<8 | SAFNUM_VPNUNICAST): case (AFNUM_IP<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_IP<<8 | SAFNUM_VPNUNIMULTICAST): if (tnhlen < sizeof(nd_ipv4)+BGP_VPN_RD_LEN) { ND_PRINT("invalid len"); tptr += tnhlen; tlen -= tnhlen; tnhlen = 0; } else { ND_PRINT("RD: %s, %s", bgp_vpn_rd_print(ndo, tptr), GET_IPADDR_STRING(tptr+BGP_VPN_RD_LEN)); tptr += (sizeof(nd_ipv4)+BGP_VPN_RD_LEN); tlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN); tnhlen -= (sizeof(nd_ipv4)+BGP_VPN_RD_LEN); } break; case (AFNUM_IP6<<8 | SAFNUM_UNICAST): case (AFNUM_IP6<<8 | SAFNUM_MULTICAST): case (AFNUM_IP6<<8 | SAFNUM_UNIMULTICAST): case (AFNUM_IP6<<8 | SAFNUM_LABUNICAST): if (tnhlen < sizeof(nd_ipv6)) { ND_PRINT("invalid len"); tptr += tnhlen; tlen -= tnhlen; tnhlen = 0; } else { ND_PRINT("%s", GET_IP6ADDR_STRING(tptr)); tptr += sizeof(nd_ipv6); tlen -= sizeof(nd_ipv6); tnhlen -= sizeof(nd_ipv6); } break; case (AFNUM_IP6<<8 | SAFNUM_VPNUNICAST): case (AFNUM_IP6<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_IP6<<8 | SAFNUM_VPNUNIMULTICAST): if (tnhlen < sizeof(nd_ipv6)+BGP_VPN_RD_LEN) { ND_PRINT("invalid len"); tptr += tnhlen; tlen -= tnhlen; tnhlen = 0; } else { ND_PRINT("RD: %s, %s", bgp_vpn_rd_print(ndo, tptr), GET_IP6ADDR_STRING(tptr+BGP_VPN_RD_LEN)); tptr += (sizeof(nd_ipv6)+BGP_VPN_RD_LEN); tlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN); tnhlen -= (sizeof(nd_ipv6)+BGP_VPN_RD_LEN); } break; case (AFNUM_VPLS<<8 | SAFNUM_VPLS): case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNICAST): case (AFNUM_L2VPN<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_L2VPN<<8 | SAFNUM_VPNUNIMULTICAST): if (tnhlen < sizeof(nd_ipv4)) { ND_PRINT("invalid len"); tptr += tnhlen; tlen -= tnhlen; tnhlen = 0; } else { ND_PRINT("%s", GET_IPADDR_STRING(tptr)); tptr += (sizeof(nd_ipv4)); tlen -= (sizeof(nd_ipv4)); tnhlen -= (sizeof(nd_ipv4)); } break; case (AFNUM_NSAP<<8 | SAFNUM_UNICAST): case (AFNUM_NSAP<<8 | SAFNUM_MULTICAST): case (AFNUM_NSAP<<8 | SAFNUM_UNIMULTICAST): ND_PRINT("%s", GET_ISONSAP_STRING(tptr, tnhlen)); tptr += tnhlen; tlen -= tnhlen; tnhlen = 0; break; case (AFNUM_NSAP<<8 | SAFNUM_VPNUNICAST): case (AFNUM_NSAP<<8 | SAFNUM_VPNMULTICAST): case (AFNUM_NSAP<<8 | SAFNUM_VPNUNIMULTICAST): if (tnhlen < BGP_VPN_RD_LEN+1) { ND_PRINT("invalid len"); tptr += tnhlen; tlen -= tnhlen; tnhlen = 0; } else { ND_TCHECK_LEN(tptr, tnhlen); ND_PRINT("RD: %s, %s", bgp_vpn_rd_print(ndo, tptr), GET_ISONSAP_STRING(tptr+BGP_VPN_RD_LEN,tnhlen-BGP_VPN_RD_LEN)); /* rfc986 mapped IPv4 address ? */ if (GET_BE_U_4(tptr + BGP_VPN_RD_LEN) == 0x47000601) ND_PRINT(" = %s", GET_IPADDR_STRING(tptr+BGP_VPN_RD_LEN+4)); /* rfc1888 mapped IPv6 address ? */ else if (GET_BE_U_3(tptr + BGP_VPN_RD_LEN) == 0x350000) ND_PRINT(" = %s", GET_IP6ADDR_STRING(tptr+BGP_VPN_RD_LEN+3)); tptr += tnhlen; tlen -= tnhlen; tnhlen = 0; } break; default: /* * bgp_mp_af_print() should have saved us from * an unsupported AFI/SAFI. */ ND_PRINT("ERROR: no AFI %u/SAFI %u nexthop decoder", af, safi); tptr += tnhlen; tlen -= tnhlen; tnhlen = 0; goto done; break; } } } ND_PRINT(", nh-length: %u", nhlen); /* As per RFC 2858; this is reserved in RFC 4760 */ if (tlen < 1) goto trunc; snpa = GET_U_1(tptr); tptr++; tlen--; if (snpa) { ND_PRINT("\n\t %u SNPA", snpa); for (/*nothing*/; snpa != 0; snpa--) { uint8_t snpalen; if (tlen < 1) goto trunc; snpalen = GET_U_1(tptr); ND_PRINT("\n\t %u bytes", snpalen); tptr++; tlen--; if (tlen < snpalen) goto trunc; ND_TCHECK_LEN(tptr, snpalen); tptr += snpalen; tlen -= snpalen; } } else { ND_PRINT(", no SNPA"); } add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32); add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128); while (tptr < pptr + len) { advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf), add_path4, add_path6); if (advance == -2) goto trunc; if (advance < 0) break; tptr += advance; } break; case BGPTYPE_MP_UNREACH_NLRI: ND_TCHECK_LEN(tptr, BGP_MP_NLRI_MINSIZE); ret = bgp_mp_af_print(ndo, tptr, tlen, &af, &safi); if (ret == -2) goto trunc; if (ret < 0) break; if (len == BGP_MP_NLRI_MINSIZE) ND_PRINT("\n\t End-of-Rib Marker (empty NLRI)"); tptr += 3; add_path4 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 32); add_path6 = check_add_path(ndo, tptr, (len-ND_BYTES_BETWEEN(tptr, pptr)), 128); while (tptr < pptr + len) { advance = bgp_nlri_print(ndo, af, safi, tptr, len, buf, sizeof(buf), add_path4, add_path6); if (advance == -2) goto trunc; if (advance < 0) break; tptr += advance; } break; case BGPTYPE_EXTD_COMMUNITIES: if (len % 8) { ND_PRINT("invalid len"); break; } while (tlen != 0) { uint16_t extd_comm; ND_TCHECK_2(tptr); if (tlen < 2) goto trunc; extd_comm=GET_BE_U_2(tptr); ND_PRINT("\n\t %s (0x%04x), Flags [%s]", tok2str(bgp_extd_comm_subtype_values, "unknown extd community typecode", extd_comm), extd_comm, bittok2str(bgp_extd_comm_flag_values, "none", extd_comm)); ND_TCHECK_8(tptr); if (tlen < 8) goto trunc; ND_PRINT(": "); bgp_extended_community_print(ndo, tptr); tlen -= 8; tptr += 8; } break; case BGPTYPE_PMSI_TUNNEL: { uint8_t tunnel_type, flags; ND_TCHECK_5(tptr); if (tlen < 5) goto trunc; flags = GET_U_1(tptr); tunnel_type = GET_U_1(tptr + 1); ND_PRINT("\n\t Tunnel-type %s (%u), Flags [%s], MPLS Label %u", tok2str(bgp_pmsi_tunnel_values, "Unknown", tunnel_type), tunnel_type, bittok2str(bgp_pmsi_flag_values, "none", flags), GET_BE_U_3(tptr + 2)>>4); tptr +=5; tlen -= 5; switch (tunnel_type) { case BGP_PMSI_TUNNEL_PIM_SM: /* fall through */ case BGP_PMSI_TUNNEL_PIM_BIDIR: ND_PRINT("\n\t Sender %s, P-Group %s", GET_IPADDR_STRING(tptr), GET_IPADDR_STRING(tptr+4)); break; case BGP_PMSI_TUNNEL_PIM_SSM: ND_PRINT("\n\t Root-Node %s, P-Group %s", GET_IPADDR_STRING(tptr), GET_IPADDR_STRING(tptr+4)); break; case BGP_PMSI_TUNNEL_INGRESS: ND_PRINT("\n\t Tunnel-Endpoint %s", GET_IPADDR_STRING(tptr)); break; case BGP_PMSI_TUNNEL_LDP_P2MP: /* fall through */ case BGP_PMSI_TUNNEL_LDP_MP2MP: ND_PRINT("\n\t Root-Node %s, LSP-ID 0x%08x", GET_IPADDR_STRING(tptr), GET_BE_U_4(tptr + 4)); break; case BGP_PMSI_TUNNEL_RSVP_P2MP: ND_PRINT("\n\t Extended-Tunnel-ID %s, P2MP-ID 0x%08x", GET_IPADDR_STRING(tptr), GET_BE_U_4(tptr + 4)); break; default: if (ndo->ndo_vflag <= 1) { print_unknown_data(ndo, tptr, "\n\t ", tlen); } } break; } case BGPTYPE_AIGP: { uint8_t type; uint16_t length; while (tlen >= 3) { type = GET_U_1(tptr); length = GET_BE_U_2(tptr + 1); tptr += 3; tlen -= 3; ND_PRINT("\n\t %s TLV (%u), length %u", tok2str(bgp_aigp_values, "Unknown", type), type, length); if (length < 3) goto trunc; length -= 3; /* * Check if we can read the TLV data. */ if (tlen < length) goto trunc; switch (type) { case BGP_AIGP_TLV: if (length < 8) goto trunc; ND_PRINT(", metric %" PRIu64, GET_BE_U_8(tptr)); break; default: if (ndo->ndo_vflag <= 1) { print_unknown_data(ndo, tptr,"\n\t ", length); } } tptr += length; tlen -= length; } break; } case BGPTYPE_ATTR_SET: ND_TCHECK_4(tptr); if (len < 4) goto trunc; ND_PRINT("\n\t Origin AS: %s", as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(tptr))); tptr += 4; len -= 4; while (len) { u_int aflags, alenlen, alen; ND_TCHECK_2(tptr); if (len < 2) { ND_PRINT(" [path attr too short]"); tptr += len; break; } aflags = GET_U_1(tptr); atype = GET_U_1(tptr + 1); tptr += 2; len -= 2; alenlen = bgp_attr_lenlen(aflags, tptr); ND_TCHECK_LEN(tptr, alenlen); if (len < alenlen) { ND_PRINT(" [path attr too short]"); tptr += len; break; } alen = bgp_attr_len(aflags, tptr); tptr += alenlen; len -= alenlen; ND_PRINT("\n\t %s (%u), length: %u", tok2str(bgp_attr_values, "Unknown Attribute", atype), atype, alen); if (aflags) { ND_PRINT(", Flags [%s", bittok2str_nosep(bgp_flags, "", aflags)); if (aflags & 0xf) ND_PRINT("+%x", aflags & 0xf); ND_PRINT("]"); } ND_PRINT(": "); if (len < alen) { ND_PRINT(" [path attr too short]"); tptr += len; break; } /* * The protocol encoding per se allows ATTR_SET to be nested * as many times as the message can accommodate. This printer * used to be able to recurse into ATTR_SET contents until the * stack exhaustion, but now there is a limit on that (if live * protocol exchange goes that many levels deep, something is * probably wrong anyway). Feel free to refine this value if * you can find the spec with respective normative text. */ if (attr_set_level == 10) ND_PRINT("(too many nested levels, not recursing)"); else if (!bgp_attr_print(ndo, atype, tptr, alen, attr_set_level + 1)) return 0; tptr += alen; len -= alen; } break; case BGPTYPE_LARGE_COMMUNITY: if (len == 0 || len % 12) { ND_PRINT("invalid len"); break; } ND_PRINT("\n\t "); while (len != 0) { ND_PRINT("%u:%u:%u%s", GET_BE_U_4(tptr), GET_BE_U_4(tptr + 4), GET_BE_U_4(tptr + 8), (len > 12) ? ", " : ""); tptr += 12; /* * len will always be a multiple of 12, as per the above, * so this will never underflow. */ len -= 12; } break; case BGPTYPE_BGPSEC_PATH: { uint16_t sblen, splen; splen = GET_BE_U_2(tptr); /* * A secure path has a minimum length of 8 bytes: * 2 bytes length field * 6 bytes per secure path segment */ ND_ICHECKMSG_U("secure path length", splen, <, 8); ND_PRINT("\n\t Secure Path Length: %u", splen); tptr += 2; splen -= 2; /* Make sure the secure path length does not signal trailing bytes */ if (splen % 6) { ND_PRINT(" [total segments length %u != N x 6]", splen); goto invalid; } /* Parse secure path segments */ while (splen != 0) { uint8_t pcount = GET_U_1(tptr); uint8_t flags = GET_U_1(tptr + 1); uint32_t asn = GET_BE_U_4(tptr + 2); ND_PRINT("\n\t Secure Path Segment: pCount: %u, Flags: [%s] (0x%02x), AS: %u", pcount, bittok2str(bgp_bgpsec_bitmap_str, "none", flags), flags, asn); tptr += 6; splen -= 6; } sblen = GET_BE_U_2(tptr); ND_PRINT("\n\t Signature Block: Length: %u, Algo ID: %u", sblen, GET_U_1(tptr + 2)); tptr += 3; sblen -= 3; /* Parse signature segments */ while (sblen > 0) { uint16_t siglen; ND_PRINT("\n\t Signature Segment:\n\t SKI: "); ND_ICHECKMSG_U("remaining length", sblen, <, 20); hex_print(ndo, "\n\t ", tptr, 20); tptr += 20; sblen -= 20; ND_ICHECKMSG_U("remaining length", sblen, <, 2); siglen = GET_BE_U_2(tptr); tptr += 2; sblen -= 2; ND_PRINT("\n\t Length: %u", siglen); ND_ICHECKMSG_U("remaining length", sblen, <, siglen); ND_PRINT("\n\t Signature:"); hex_print(ndo, "\n\t ", tptr, siglen); tptr += siglen; sblen -= siglen; } break; } case BGPTYPE_OTC: { if (len < 4) { ND_PRINT("invalid len"); break; } ND_PRINT("\n\t OTC %u", GET_BE_U_4(pptr)); break; } default: ND_TCHECK_LEN(pptr, len); ND_PRINT("\n\t no Attribute %u decoder", atype); /* we have no decoder for the attribute */ if (ndo->ndo_vflag <= 1) print_unknown_data(ndo, pptr, "\n\t ", len); break; } done: if (ndo->ndo_vflag > 1 && len) { /* omit zero length attributes*/ ND_TCHECK_LEN(pptr, len); print_unknown_data(ndo, pptr, "\n\t ", len); } return 1; invalid: nd_print_invalid(ndo); return 1; trunc: return 0; } static void bgp_capabilities_print(netdissect_options *ndo, const u_char *opt, u_int caps_len) { /* allocate space for the largest possible string */ char astostr[AS_STR_SIZE]; u_int cap_type, cap_len, tcap_len, cap_offset; u_int i = 0; while (i < caps_len) { ND_TCHECK_LEN(opt + i, BGP_CAP_HEADER_SIZE); cap_type=GET_U_1(opt + i); cap_len=GET_U_1(opt + i + 1); ND_PRINT("\n\t %s (%u), length: %u", tok2str(bgp_capcode_values, "Unknown", cap_type), cap_type, cap_len); ND_TCHECK_LEN(opt + 2 + i, cap_len); switch (cap_type) { case BGP_CAPCODE_MP: /* AFI (16 bits), Reserved (8 bits), SAFI (8 bits) */ if (cap_len < 4) { ND_PRINT(" (too short, < 4)"); return; } ND_PRINT("\n\t\tAFI %s (%u), SAFI %s (%u)", tok2str(af_values, "Unknown", GET_BE_U_2(opt + i + 2)), GET_BE_U_2(opt + i + 2), tok2str(bgp_safi_values, "Unknown", GET_U_1(opt + i + 5)), GET_U_1(opt + i + 5)); break; case BGP_CAPCODE_BGPSEC: /* Version (4 bits), Direction (1 bit), Flags (3 bits), AFI (16 bits) */ cap_offset = 1; /* The capability length [...] MUST be set to 3. */ if (cap_len != 3) { ND_PRINT(" [%u != 3]", cap_len); return; } ND_PRINT("\n\t\tVersion %u, Direction %s (%u), AFI %s (%u)", GET_U_1(opt + i + 2)&0xf0, (GET_U_1(opt + i + 2)&0x08) ? "Send" : "Receive", (GET_U_1(opt + i + 2)&0x08)>>3, bittok2str(af_values, "Unknown", GET_BE_U_2(opt + i + cap_offset + 2)), GET_BE_U_2(opt + i + cap_offset + 2)); break; case BGP_CAPCODE_ML: cap_offset = 2; tcap_len = cap_len; while (tcap_len >= 4) { ND_PRINT( "\n\t\tAFI %s (%u), SAFI %s (%u), Count: %u", tok2str(af_values, "Unknown", GET_BE_U_2(opt + i + cap_offset)), GET_BE_U_2(opt + i + cap_offset), tok2str(bgp_safi_values, "Unknown", GET_U_1(opt + i + cap_offset + 2)), GET_U_1(opt + i + cap_offset + 2), GET_U_1(opt + i + cap_offset + 3)); tcap_len -= 4; cap_offset += 4; } break; case BGP_CAPCODE_RESTART: /* Restart Flags (4 bits), Restart Time in seconds (12 bits) */ if (cap_len < 2) { ND_PRINT(" (too short, < 2)"); return; } tcap_len=cap_len; ND_PRINT("\n\t\tRestart Flags: [%s], Restart Time %us", bittok2str(bgp_graceful_restart_comm_flag_values, "none", GET_U_1(opt + i + 2) >> 4), GET_BE_U_2(opt + i + 2)&0xfff); tcap_len-=2; cap_offset=4; while(tcap_len>=4) { ND_PRINT("\n\t\t AFI %s (%u), SAFI %s (%u), Forwarding state preserved: %s", tok2str(af_values,"Unknown", GET_BE_U_2(opt + i + cap_offset)), GET_BE_U_2(opt + i + cap_offset), tok2str(bgp_safi_values,"Unknown", GET_U_1(opt + i + cap_offset + 2)), GET_U_1(opt + (i + cap_offset + 2)), ((GET_U_1(opt + (i + cap_offset + 3)))&0x80) ? "yes" : "no" ); tcap_len -= 4; cap_offset += 4; } break; case BGP_CAPCODE_ROLE: if (cap_len < 1) { ND_PRINT(" (too short, < 1)"); return; } ND_PRINT("\n\t\tRole name %s (%u)", tok2str(bgp_role_values, "Unassigned", GET_U_1(opt + i + 2)), GET_U_1(opt + i + 2)); break; case BGP_CAPCODE_RR: case BGP_CAPCODE_LLGR: case BGP_CAPCODE_RR_CISCO: case BGP_CAPCODE_EXT_MSG: case BGP_CAPCODE_ENH_RR: break; case BGP_CAPCODE_AS_NEW: /* * Extract the 4 byte AS number encoded. */ if (cap_len < 4) { ND_PRINT(" (too short, < 4)"); return; } ND_PRINT("\n\t\t 4 Byte AS %s", as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_4(opt + i + 2))); break; case BGP_CAPCODE_ADD_PATH: if (cap_len == 0) { ND_PRINT(" (bogus)"); /* length */ break; } tcap_len=cap_len; cap_offset=2; while (tcap_len != 0) { if (tcap_len < 4) { nd_print_invalid(ndo); break; } ND_PRINT("\n\t\tAFI %s (%u), SAFI %s (%u), Send/Receive: %s", tok2str(af_values,"Unknown",GET_BE_U_2(opt + i + cap_offset)), GET_BE_U_2(opt + i + cap_offset), tok2str(bgp_safi_values,"Unknown",GET_U_1(opt + i + cap_offset + 2)), GET_U_1(opt + (i + cap_offset + 2)), tok2str(bgp_add_path_recvsend,"Bogus (0x%02x)",GET_U_1(opt + i + cap_offset + 3)) ); tcap_len -= 4; cap_offset += 4; } break; default: ND_PRINT("\n\t\tno decoder for Capability %u", cap_type); if (ndo->ndo_vflag <= 1) print_unknown_data(ndo, opt + i + 2, "\n\t\t", cap_len); break; } if (ndo->ndo_vflag > 1 && cap_len != 0) { print_unknown_data(ndo, opt + i + 2, "\n\t\t", cap_len); } i += BGP_CAP_HEADER_SIZE + cap_len; } return; trunc: nd_print_trunc(ndo); } static void bgp_open_print(netdissect_options *ndo, const u_char *dat, u_int length) { /* allocate space for the largest possible string */ char astostr[AS_STR_SIZE]; const struct bgp_open *bgp_open_header; u_int optslen; uint8_t opsttype; const struct bgp_opt *bgpopt; const u_char *opt; u_int i; uint8_t extended_opt_params = 0; u_int open_size = BGP_OPEN_SIZE; u_int opt_size = BGP_OPT_SIZE; ND_TCHECK_LEN(dat, BGP_OPEN_SIZE); if (length < BGP_OPEN_SIZE) goto trunc; bgp_open_header = (const struct bgp_open *)dat; ND_PRINT("\n\t Version %u, ", GET_U_1(bgp_open_header->bgpo_version)); ND_PRINT("my AS %s, ", as_printf(ndo, astostr, sizeof(astostr), GET_BE_U_2(bgp_open_header->bgpo_myas))); ND_PRINT("Holdtime %us, ", GET_BE_U_2(bgp_open_header->bgpo_holdtime)); ND_PRINT("ID %s", GET_IPADDR_STRING(bgp_open_header->bgpo_id)); optslen = GET_U_1(bgp_open_header->bgpo_optlen); opsttype = GET_U_1(bgp_open_header->bgpo_opttype); if (opsttype == BGP_OPEN_NON_EXT_OPT_TYPE_EXTENDED_LENGTH) { optslen = GET_BE_U_2(bgp_open_header->bgpo_optlen_extended); extended_opt_params = 1; open_size += 3; opt_size += 1; } ND_PRINT("\n\t Optional parameters%s, length: %u", extended_opt_params ? " (Extended)" : "", optslen); opt = dat + open_size; length -= open_size; i = 0; while (i < optslen) { uint8_t opt_type; uint16_t opt_len; ND_TCHECK_LEN(opt + i, opt_size); if (length < opt_size + i) goto trunc; bgpopt = (const struct bgp_opt *)(opt + i); opt_type = GET_U_1(bgpopt->bgpopt_type); opt_len = extended_opt_params ? GET_BE_U_2(bgpopt->bgpopt_len) : GET_U_1(bgpopt->bgpopt_len); if (opt_size + i + opt_len > optslen) { ND_PRINT("\n\t Option %u, length: %u, goes past the end of the options", opt_type, opt_len); break; } ND_PRINT("\n\t Option %s (%u), length: %u", tok2str(bgp_opt_values,"Unknown",opt_type), opt_type, opt_len); /* now let's decode the options we know*/ switch(opt_type) { case BGP_OPT_CAP: bgp_capabilities_print(ndo, opt + opt_size + i, opt_len); break; case BGP_OPT_AUTH: default: ND_PRINT("\n\t no decoder for option %u", opt_type); break; } i += opt_size + opt_len; } return; trunc: nd_print_trunc(ndo); } static void bgp_update_print(netdissect_options *ndo, const u_char *dat, u_int length) { const u_char *p; u_int withdrawn_routes_len; char buf[MAXHOSTNAMELEN + 100]; int wpfx; u_int len; int i; int add_path; u_int path_id = 0; ND_TCHECK_LEN(dat, BGP_SIZE); if (length < BGP_SIZE) goto trunc; p = dat + BGP_SIZE; length -= BGP_SIZE; /* Unfeasible routes */ ND_TCHECK_2(p); if (length < 2) goto trunc; withdrawn_routes_len = GET_BE_U_2(p); p += 2; length -= 2; if (withdrawn_routes_len > 1) { /* * Without keeping state from the original NLRI message, * it's not possible to tell if this a v4 or v6 route, * so only try to decode it if we're not v6 enabled. */ ND_TCHECK_LEN(p, withdrawn_routes_len); if (length < withdrawn_routes_len) goto trunc; ND_PRINT("\n\t Withdrawn routes:"); add_path = check_add_path(ndo, p, withdrawn_routes_len, 32); while (withdrawn_routes_len != 0) { if (add_path) { if (withdrawn_routes_len < 4) { p += withdrawn_routes_len; length -= withdrawn_routes_len; break; } path_id = GET_BE_U_4(p); p += 4; length -= 4; withdrawn_routes_len -= 4; } wpfx = decode_prefix4(ndo, p, withdrawn_routes_len, buf, sizeof(buf)); if (wpfx == -1) { ND_PRINT("\n\t (illegal prefix length)"); break; } else if (wpfx == -2) goto trunc; /* bytes left, but not enough */ else { ND_PRINT("\n\t %s", buf); if (add_path) { ND_PRINT(" Path Id: %u", path_id); } p += wpfx; length -= wpfx; withdrawn_routes_len -= wpfx; } } } else { ND_TCHECK_LEN(p, withdrawn_routes_len); if (length < withdrawn_routes_len) goto trunc; p += withdrawn_routes_len; length -= withdrawn_routes_len; } ND_TCHECK_2(p); if (length < 2) goto trunc; len = GET_BE_U_2(p); p += 2; length -= 2; if (withdrawn_routes_len == 0 && len == 0 && length == 0) { /* No withdrawn routes, no path attributes, no NLRI */ ND_PRINT("\n\t End-of-Rib Marker (empty NLRI)"); return; } if (len) { /* Make sure the path attributes don't go past the end of the packet */ if (length < len) goto trunc; /* do something more useful!*/ while (len) { uint8_t aflags, atype, alenlen; uint16_t alen; ND_TCHECK_2(p); if (length < 2) goto trunc; if (len < 2) { ND_PRINT("\n\t [path attrs too short]"); p += len; length -= len; break; } aflags = GET_U_1(p); atype = GET_U_1(p + 1); p += 2; len -= 2; length -= 2; alenlen = bgp_attr_lenlen(aflags, p); ND_TCHECK_LEN(p, alenlen); if (length < alenlen) goto trunc; if (len < alenlen) { ND_PRINT("\n\t [path attrs too short]"); p += len; length -= len; break; } alen = bgp_attr_len(aflags, p); p += alenlen; len -= alenlen; length -= alenlen; ND_PRINT("\n\t %s (%u), length: %u", tok2str(bgp_attr_values, "Unknown Attribute", atype), atype, alen); if (aflags) { ND_PRINT(", Flags [%s", bittok2str_nosep(bgp_flags, "", aflags)); if (aflags & 0xf) ND_PRINT("+%x", aflags & 0xf); ND_PRINT("]: "); } if (len < alen) { ND_PRINT(" [path attrs too short]"); p += len; length -= len; break; } if (length < alen) goto trunc; if (!bgp_attr_print(ndo, atype, p, alen, 0)) goto trunc; p += alen; len -= alen; length -= alen; } } if (length) { add_path = check_add_path(ndo, p, length, 32); ND_PRINT("\n\t Updated routes:"); while (length != 0) { if (add_path) { ND_TCHECK_4(p); if (length < 4) goto trunc; path_id = GET_BE_U_4(p); p += 4; length -= 4; } i = decode_prefix4(ndo, p, length, buf, sizeof(buf)); if (i == -1) { ND_PRINT("\n\t (illegal prefix length)"); break; } else if (i == -2) goto trunc; /* bytes left, but not enough */ else { ND_PRINT("\n\t %s", buf); if (add_path) { ND_PRINT(" Path Id: %u", path_id); } p += i; length -= i; } } } return; trunc: nd_print_trunc(ndo); } static void bgp_notification_print_code(netdissect_options *ndo, const u_char *dat, u_int length, uint8_t bgpn_major, uint8_t bgpn_minor) { ND_PRINT(", %s (%u)", tok2str(bgp_notify_major_values, "Unknown Error", bgpn_major), bgpn_major); switch (bgpn_major) { case BGP_NOTIFY_MAJOR_MSG: ND_PRINT(", subcode %s (%u)", tok2str(bgp_notify_minor_msg_values, "Unknown", bgpn_minor), bgpn_minor); break; case BGP_NOTIFY_MAJOR_OPEN: ND_PRINT(", subcode %s (%u)", tok2str(bgp_notify_minor_open_values, "Unknown", bgpn_minor), bgpn_minor); break; case BGP_NOTIFY_MAJOR_UPDATE: ND_PRINT(", subcode %s (%u)", tok2str(bgp_notify_minor_update_values, "Unknown", bgpn_minor), bgpn_minor); break; case BGP_NOTIFY_MAJOR_FSM: ND_PRINT(" subcode %s (%u)", tok2str(bgp_notify_minor_fsm_values, "Unknown", bgpn_minor), bgpn_minor); break; case BGP_NOTIFY_MAJOR_CAP: ND_PRINT(" subcode %s (%u)", tok2str(bgp_notify_minor_cap_values, "Unknown", bgpn_minor), bgpn_minor); break; case BGP_NOTIFY_MAJOR_CEASE: ND_PRINT(", subcode %s (%u)", tok2str(bgp_notify_minor_cease_values, "Unknown", bgpn_minor), bgpn_minor); /* RFC 4486 mentions optionally 7 bytes * for the maxprefix subtype, which may contain AFI, SAFI and MAXPREFIXES */ if(bgpn_minor == BGP_NOTIFY_MINOR_CEASE_MAXPRFX && length >= 7) { ND_PRINT(", AFI %s (%u), SAFI %s (%u), Max Prefixes: %u", tok2str(af_values, "Unknown", GET_BE_U_2(dat)), GET_BE_U_2(dat), tok2str(bgp_safi_values, "Unknown", GET_U_1((dat + 2))), GET_U_1((dat + 2)), GET_BE_U_4(dat + 3)); } /* * RFC 9003 describes a method to send a communication * intended for human consumption regarding the Administrative Shutdown */ if ((bgpn_minor == BGP_NOTIFY_MINOR_CEASE_SHUT || bgpn_minor == BGP_NOTIFY_MINOR_CEASE_RESET) && length >= 1) { uint8_t shutdown_comm_length = GET_U_1(dat); uint8_t remainder_offset = 0; /* garbage, hexdump it all */ if (shutdown_comm_length > length - 1) { ND_PRINT(", invalid Shutdown Communication length"); } else if (shutdown_comm_length == 0) { ND_PRINT(", empty Shutdown Communication"); remainder_offset += 1; } /* a proper shutdown communication */ else { ND_PRINT(", Shutdown Communication (length: %u): \"", shutdown_comm_length); nd_printjn(ndo, dat+1, shutdown_comm_length); ND_PRINT("\""); remainder_offset += shutdown_comm_length + 1; } /* if there is trailing data, hexdump it */ if(length - remainder_offset > 0) { ND_PRINT(", Data: (length: %u)", length - remainder_offset); hex_print(ndo, "\n\t\t", dat + remainder_offset, length - remainder_offset); } } /* * RFC8538 describes the Hard Reset cease subcode, which contains another * notification code and subcode. */ if (bgpn_minor == BGP_NOTIFY_MINOR_CEASE_HARDRESET && length >= 2) { bgpn_major = GET_U_1(dat++); bgpn_minor = GET_U_1(dat++); length -= 2; bgp_notification_print_code(ndo, dat, length, bgpn_major, bgpn_minor); } break; default: if (bgpn_minor != 0) { ND_PRINT(", subcode %u", bgpn_minor); } break; } return; } static void bgp_notification_print(netdissect_options *ndo, const u_char *dat, u_int length) { const struct bgp_notification *bgp_notification_header; uint8_t bgpn_major, bgpn_minor; ND_TCHECK_LEN(dat, BGP_NOTIFICATION_SIZE); if (lengthbgpn_major); bgpn_minor = GET_U_1(bgp_notification_header->bgpn_minor); bgp_notification_print_code(ndo, dat + BGP_NOTIFICATION_SIZE, length - BGP_NOTIFICATION_SIZE, bgpn_major, bgpn_minor); return; trunc: nd_print_trunc(ndo); } static void bgp_route_refresh_print(netdissect_options *ndo, const u_char *pptr, u_int len) { const struct bgp_route_refresh *bgp_route_refresh_header; /* some little sanity checking */ if (lenafi)), GET_BE_U_2(bgp_route_refresh_header->afi), tok2str(bgp_safi_values, "Unknown", GET_U_1(bgp_route_refresh_header->safi)), GET_U_1(bgp_route_refresh_header->safi), tok2str(bgp_route_refresh_subtype_values, "Unknown", GET_U_1(bgp_route_refresh_header->subtype)), GET_U_1(bgp_route_refresh_header->subtype)); /* ORF */ if (len >= BGP_ROUTE_REFRESH_SIZE_ORF) { const struct bgp_route_refresh_orf *orf_header; orf_header = (const struct bgp_route_refresh_orf *)(pptr + BGP_ROUTE_REFRESH_SIZE); ND_PRINT("\n\t ORF refresh %s (%u), ORF type %s (%u), ORF length %u", tok2str(bgp_orf_refresh_type, "Unknown", GET_U_1(orf_header->refresh)), GET_U_1(orf_header->refresh), tok2str(bgp_orf_type, "Unknown", GET_U_1(orf_header->type)), GET_U_1(orf_header->type), GET_BE_U_2(orf_header->len)); } if (ndo->ndo_vflag > 1) { ND_TCHECK_LEN(pptr, len); print_unknown_data(ndo, pptr, "\n\t ", len); } return; trunc: nd_print_trunc(ndo); } static int bgp_pdu_print(netdissect_options *ndo, const u_char *dat, u_int length) { const struct bgp *bgp_header; uint8_t bgp_type; ND_TCHECK_LEN(dat, BGP_SIZE); bgp_header = (const struct bgp *)dat; bgp_type = GET_U_1(bgp_header->bgp_type); ND_PRINT("\n\t%s Message (%u), length: %u", tok2str(bgp_msg_values, "Unknown", bgp_type), bgp_type, length); switch (bgp_type) { case BGP_OPEN: bgp_open_print(ndo, dat, length); break; case BGP_UPDATE: bgp_update_print(ndo, dat, length); break; case BGP_NOTIFICATION: bgp_notification_print(ndo, dat, length); break; case BGP_KEEPALIVE: break; case BGP_ROUTE_REFRESH: bgp_route_refresh_print(ndo, dat, length); break; default: /* we have no decoder for the BGP message */ ND_TCHECK_LEN(dat, length); ND_PRINT("\n\t no Message %u decoder", bgp_type); print_unknown_data(ndo, dat, "\n\t ", length); break; } return 1; trunc: nd_print_trunc(ndo); return 0; } void bgp_print(netdissect_options *ndo, const u_char *dat, u_int length _U_) { const u_char *p; const u_char *ep = ndo->ndo_snapend; const u_char *start; const u_char marker[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, }; const struct bgp *bgp_header; uint16_t hlen; ndo->ndo_protocol = "bgp"; ND_PRINT(": BGP"); if (ndo->ndo_vflag < 1) /* lets be less chatty */ return; p = dat; start = p; while (p < ep) { if (!ND_TTEST_1(p)) break; if (GET_U_1(p) != 0xff) { p++; continue; } if (!ND_TTEST_LEN(p, sizeof(marker))) break; if (memcmp(p, marker, sizeof(marker)) != 0) { p++; continue; } /* found BGP header */ ND_TCHECK_LEN(p, BGP_SIZE); bgp_header = (const struct bgp *)p; if (start != p) nd_print_trunc(ndo); hlen = GET_BE_U_2(bgp_header->bgp_len); if (hlen < BGP_SIZE) { ND_PRINT("\nmessage length %u < %u", hlen, BGP_SIZE); nd_print_invalid(ndo); break; } if (ND_TTEST_LEN(p, hlen)) { if (!bgp_pdu_print(ndo, p, hlen)) return; p += hlen; start = p; } else { ND_PRINT("\n[|BGP %s]", tok2str(bgp_msg_values, "Unknown Message Type", GET_U_1(bgp_header->bgp_type))); break; } } return; trunc: nd_print_trunc(ndo); }