95b01dc4bf
This dissector is for the control messages of the GRE bonding protocol by Huawei. These messages are encapsulated in GRE and can appear on both/all bonding links. During development, I made heavy use of traffic for Deutsche Telekom Hybrid service. There fore, it also supports the first version which did not have an IEEE assigned ethertype.
776 lines
29 KiB
C
776 lines
29 KiB
C
/* packet-gre.c
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* Routines for the Generic Routing Encapsulation (GRE) protocol
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* Brad Robel-Forrest <brad.robel-forrest@watchguard.com>
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*
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* Wireshark - Network traffic analyzer
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* By Gerald Combs <gerald@wireshark.org>
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* Copyright 1998 Gerald Combs
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*
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* SPDX-License-Identifier: GPL-2.0-or-later
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*/
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#include "config.h"
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#include <epan/packet.h>
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#include <epan/capture_dissectors.h>
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#include <epan/etypes.h>
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#include <epan/in_cksum.h>
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#include <epan/expert.h>
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#include <epan/ipproto.h>
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#include <epan/llcsaps.h>
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#include "packet-gre.h"
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#include "packet-wccp.h"
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#define GRE_IN_UDP_PORT 4754
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void proto_register_gre(void);
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void proto_reg_handoff_gre(void);
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/*
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* See RFC 1701 "Generic Routing Encapsulation (GRE)", RFC 1702
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* "Generic Routing Encapsulation over IPv4 networks", RFC 2637
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* "Point-to-Point Tunneling Protocol (PPTP)", RFC 2784 "Generic
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* Routing Encapsulation (GRE)", RFC 2890 "Key and Sequence
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* Number Extensions to GRE", RFC 8086 "GRE-in-UDP Encapsulation",
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* and draft-ietf-mpls-in-ip-or-gre-07.txt
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* "Encapsulating MPLS in IP or Generic Routing Encapsulation (GRE)".
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*/
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static int proto_gre = -1;
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static int hf_gre_proto = -1;
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static int hf_gre_flags_and_version = -1;
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static int hf_gre_flags_checksum = -1;
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static int hf_gre_flags_routing = -1;
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static int hf_gre_flags_key = -1;
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static int hf_gre_flags_sequence_number = -1;
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static int hf_gre_flags_strict_source_route = -1;
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static int hf_gre_flags_recursion_control = -1;
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static int hf_gre_flags_ack = -1;
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static int hf_gre_flags_reserved_ppp = -1;
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static int hf_gre_flags_reserved = -1;
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static int hf_gre_flags_version = -1;
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static int hf_gre_checksum = -1;
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static int hf_gre_checksum_status = -1;
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static int hf_gre_offset = -1;
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static int hf_gre_key = -1;
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static int hf_gre_key_payload_length = -1;
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static int hf_gre_key_call_id = -1;
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static int hf_gre_sequence_number = -1;
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static int hf_gre_ack_number = -1;
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static int hf_gre_routing = -1;
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static int hf_gre_routing_address_family = -1;
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static int hf_gre_routing_sre_length = -1;
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static int hf_gre_routing_sre_offset = -1;
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static int hf_gre_routing_information = -1;
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/* Ref 3GPP2 A.S0012-C v2.0 and A.S0008-A v1.0 */
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static int hf_gre_3gpp2_attrib = -1;
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static int hf_gre_3gpp2_attrib_id = -1;
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static int hf_gre_3gpp2_attrib_length = -1;
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static int hf_gre_3gpp2_sdi = -1;
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static int hf_gre_3gpp2_fci = -1;
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static int hf_gre_3gpp2_di = -1;
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static int hf_gre_3gpp2_flow_disc = -1;
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static int hf_gre_3gpp2_seg = -1;
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static int hf_gre_wccp_redirect_header = -1;
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static int hf_gre_wccp_dynamic_service = -1;
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static int hf_gre_wccp_alternative_bucket_used = -1;
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static int hf_gre_wccp_redirect_header_valid = -1;
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static int hf_gre_wccp_service_id = -1;
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static int hf_gre_wccp_alternative_bucket = -1;
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static int hf_gre_wccp_primary_bucket = -1;
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static gint ett_gre = -1;
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static gint ett_gre_flags = -1;
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static gint ett_gre_routing = -1;
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static gint ett_gre_wccp2_redirect_header = -1;
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static gint ett_3gpp2_attribs = -1;
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static gint ett_3gpp2_attr = -1;
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static expert_field ei_gre_checksum_incorrect = EI_INIT;
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static dissector_table_t gre_dissector_table;
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static const value_string gre_version[] = {
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{ 0, "GRE" }, /* [RFC2784] */
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{ 1, "Enhanced GRE" }, /* [RFC2637] */
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{ 0, NULL}
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};
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const value_string gre_typevals[] = {
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{ GRE_KEEPALIVE, "Possible GRE keepalive packet" },
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{ ETHERTYPE_PPP, "PPP" },
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{ ETHERTYPE_IP, "IP" },
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{ ETHERTYPE_ARP, "ARP" },
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{ SAP_OSINL5, "OSI"},
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{ GRE_WCCP, "WCCP"},
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{ GRE_CISCO_CDP, "CDP (Cisco)"},
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{ GRE_NHRP, "NHRP"},
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{ GRE_ERSPAN_88BE, "ERSPAN"},
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{ GRE_ERSPAN_22EB, "ERSPAN III"},
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{ GRE_MIKROTIK_EOIP, "MIKROTIK EoIP"},
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{ GRE_AIROHIVE, "AIROHIVE AP AP"},
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{ ETHERTYPE_IPX, "IPX"},
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{ ETHERTYPE_ETHBRIDGE, "Transparent Ethernet bridging" },
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{ ETHERTYPE_RAW_FR, "Frame Relay"},
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{ ETHERTYPE_IPv6, "IPv6" },
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{ ETHERTYPE_MPLS, "MPLS label switched packet" },
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{ ETHERTYPE_NSH, "Network Service Header" },
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{ ETHERTYPE_CDMA2000_A10_UBS,"CDMA2000 A10 Unstructured byte stream" },
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{ ETHERTYPE_3GPP2, "CDMA2000 A10 3GPP2 Packet" },
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{ ETHERTYPE_CMD, "CiscoMetaData" },
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{ GRE_GREBONDING, "Huawei GRE bonding" },
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{ GRE_ARUBA_8200, "ARUBA WLAN" },
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{ GRE_ARUBA_8210, "ARUBA WLAN" },
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{ GRE_ARUBA_8220, "ARUBA WLAN" },
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{ GRE_ARUBA_8230, "ARUBA WLAN" },
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{ GRE_ARUBA_8240, "ARUBA WLAN" },
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{ GRE_ARUBA_8250, "ARUBA WLAN" },
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{ GRE_ARUBA_8260, "ARUBA WLAN" },
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{ GRE_ARUBA_8270, "ARUBA WLAN" },
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{ GRE_ARUBA_8280, "ARUBA WLAN" },
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{ GRE_ARUBA_8290, "ARUBA WLAN" },
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{ GRE_ARUBA_82A0, "ARUBA WLAN" },
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{ GRE_ARUBA_82B0, "ARUBA WLAN" },
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{ GRE_ARUBA_82C0, "ARUBA WLAN" },
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{ GRE_ARUBA_82D0, "ARUBA WLAN" },
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{ GRE_ARUBA_82E0, "ARUBA WLAN" },
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{ GRE_ARUBA_82F0, "ARUBA WLAN" },
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{ GRE_ARUBA_8300, "ARUBA WLAN" },
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{ GRE_ARUBA_8310, "ARUBA WLAN" },
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{ GRE_ARUBA_8320, "ARUBA WLAN" },
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{ GRE_ARUBA_8330, "ARUBA WLAN" },
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{ GRE_ARUBA_8340, "ARUBA WLAN" },
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{ GRE_ARUBA_8350, "ARUBA WLAN" },
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{ GRE_ARUBA_8360, "ARUBA WLAN" },
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{ GRE_ARUBA_8370, "ARUBA WLAN" },
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{ GRE_ARUBA_9000, "ARUBA WLAN" },
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{ 0, NULL }
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};
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#define ID_3GPP2_SDI_FLAG 1
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#define ID_3GPP2_FLOW_CTRL 2
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#define ID_3GPP2_FLOW_DISCRIMINATOR 3
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#define ID_3GPP2_SEG 4
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static const value_string gre_3gpp2_seg_vals[] = {
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{ 0x00, "Packet Started" },
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{ 0x01, "Packet continued" },
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{ 0x02, "Packet Ended" },
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{ 0, NULL }
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};
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/* 3GPP2 A.S0012-C v2.0
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* 2.6.1 GRE Attributes
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*/
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static const value_string gre_3gpp2_attrib_id_vals[] = {
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{ 0x01, "1x SDB/HRPD DOS Indicator" },
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{ 0x02, "Flow Control Indication" },
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/* A.S0008-A v1.0 */
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{ 0x03, "IP Flow Discriminator" },
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{ 0x04, "Segmentation Indication" },
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{ 0, NULL }
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};
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static const true_false_string gre_3gpp2_sdi_val = {
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"Packet suitable for 1x SDB or HRPD DOS transmission",
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"Reserved"
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};
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static const true_false_string gre_3gpp2_fci_val = {
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"XOFF",
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"XON"
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};
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static const true_false_string gre_3gpp2_di_val = {
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"INDEFINITE:",
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"TEMPORARY"
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};
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static const true_false_string gre_wccp_dynamic_service_val = {
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"Dynamic service",
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"Well-known service"
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};
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static const true_false_string gre_wccp_alternative_bucket_used_val = {
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"Alternative bucket used",
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"Primary bucket used",
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};
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static const true_false_string gre_wccp_redirect_header_valid_val = {
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"Header is present, but ignore contents",
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"Header contents are valid",
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};
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static int
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dissect_gre_3gpp2_attribs(tvbuff_t *tvb, int offset, proto_tree *tree)
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{
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gboolean last_attrib = FALSE;
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proto_item *attr_item;
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proto_tree *attr_tree;
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guint8 value;
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int start_offset = offset;
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proto_item *ti = proto_tree_add_item(tree, hf_gre_3gpp2_attrib, tvb, offset, 0, ENC_NA);
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proto_tree *atree = proto_item_add_subtree(ti, ett_3gpp2_attribs);
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while(last_attrib != TRUE)
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{
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guint8 attrib_id = tvb_get_guint8(tvb, offset);
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guint8 attrib_length = tvb_get_guint8(tvb, offset + 1);
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attr_tree = proto_tree_add_subtree(atree, tvb, offset, attrib_length + 1 + 1, ett_3gpp2_attr, &attr_item,
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val_to_str((attrib_id&0x7f), gre_3gpp2_attrib_id_vals, "%u (Unknown)"));
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proto_tree_add_item(attr_tree, hf_gre_3gpp2_attrib_id, tvb, offset, 1, ENC_BIG_ENDIAN);
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proto_tree_add_item(attr_tree, hf_gre_3gpp2_attrib_length, tvb, offset+1, 1, ENC_BIG_ENDIAN);
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offset += 2;
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last_attrib = (attrib_id & 0x80)?TRUE:FALSE;
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attrib_id &= 0x7F;
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switch(attrib_id)
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{
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case ID_3GPP2_FLOW_DISCRIMINATOR:
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{
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value = tvb_get_guint8(tvb,offset);
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proto_tree_add_item(attr_tree, hf_gre_3gpp2_flow_disc, tvb, offset, attrib_length, ENC_NA);
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proto_item_append_text(attr_item," - 0x%x",value);
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}
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break;
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case ID_3GPP2_SDI_FLAG:
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{
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value = tvb_get_guint8(tvb,offset);
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proto_tree_add_item(attr_tree, hf_gre_3gpp2_sdi, tvb, offset, attrib_length, ENC_BIG_ENDIAN);
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proto_item_append_text(attr_item," - %s",
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(value & 0x80) ? "Packet suitable for 1x SDB or HRPD DOS transmission" : "Reserved");
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}
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break;
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case ID_3GPP2_SEG:
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{
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value = tvb_get_guint8(tvb,offset) >>6;
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proto_tree_add_item(attr_tree, hf_gre_3gpp2_seg, tvb, offset, attrib_length, ENC_BIG_ENDIAN);
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proto_item_append_text(attr_item," - %s",val_to_str(value, gre_3gpp2_seg_vals, "0x%02X - Unknown"));
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}
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break;
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case ID_3GPP2_FLOW_CTRL:
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{
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value = tvb_get_guint8(tvb,offset);
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proto_tree_add_item(attr_tree, hf_gre_3gpp2_fci, tvb, offset, attrib_length, ENC_BIG_ENDIAN);
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proto_item_append_text(attr_item," - %s",
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(value & 0x80) ? "XON" : "XOFF");
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proto_tree_add_item(attr_tree, hf_gre_3gpp2_di, tvb, offset, attrib_length, ENC_BIG_ENDIAN);
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proto_item_append_text(attr_item,"/%s",
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(value & 0x40) ? "INDEFINITE" : "TEMPORARY");
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}
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break;
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}
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offset += attrib_length;
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}
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proto_item_set_len(ti, offset - start_offset);
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return offset;
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}
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static void
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dissect_gre_wccp2_redirect_header(tvbuff_t *tvb, int offset, proto_tree *tree)
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{
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proto_item *ti;
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proto_tree *rh_tree;
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ti = proto_tree_add_item(tree, hf_gre_wccp_redirect_header, tvb, offset, 4, ENC_NA);
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rh_tree = proto_item_add_subtree(ti, ett_gre_wccp2_redirect_header);
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proto_tree_add_item(rh_tree, hf_gre_wccp_dynamic_service, tvb, offset, 1, ENC_BIG_ENDIAN);
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proto_tree_add_item(rh_tree, hf_gre_wccp_alternative_bucket_used, tvb, offset, 1, ENC_BIG_ENDIAN);
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proto_tree_add_item(rh_tree, hf_gre_wccp_redirect_header_valid, tvb, offset, 1, ENC_BIG_ENDIAN);
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proto_tree_add_item(rh_tree, hf_gre_wccp_service_id, tvb, offset +1, 1, ENC_BIG_ENDIAN);
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proto_tree_add_item(rh_tree, hf_gre_wccp_alternative_bucket, tvb, offset +2, 1, ENC_BIG_ENDIAN);
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proto_tree_add_item(rh_tree, hf_gre_wccp_primary_bucket, tvb, offset +3, 1, ENC_BIG_ENDIAN);
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}
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static gboolean
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capture_gre(const guchar *pd _U_, int offset _U_, int len _U_, capture_packet_info_t *cpinfo, const union wtap_pseudo_header *pseudo_header _U_)
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{
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capture_dissector_increment_count(cpinfo, proto_gre);
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return TRUE;
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}
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static int
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dissect_gre(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
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{
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int offset = 0;
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guint16 flags_and_ver;
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guint16 type;
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gboolean is_ppp = FALSE;
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gboolean is_wccp2 = FALSE;
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proto_item *ti, *it_flags;
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proto_tree *gre_tree, *fv_tree = NULL;
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guint16 sre_af;
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guint8 sre_length;
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tvbuff_t *next_tvb;
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flags_and_ver = tvb_get_ntohs(tvb, offset);
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type = tvb_get_ntohs(tvb, offset + 2);
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col_set_str(pinfo->cinfo, COL_PROTOCOL, "GRE");
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col_add_fstr(pinfo->cinfo, COL_INFO, "Encapsulated %s", val_to_str(type, gre_typevals, "0x%04X (unknown)"));
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switch (type) {
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case ETHERTYPE_PPP:
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if (flags_and_ver & GRE_VERSION)
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is_ppp = TRUE;
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break;
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case ETHERTYPE_3GPP2:
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case ETHERTYPE_CDMA2000_A10_UBS:
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is_ppp = TRUE;
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break;
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case GRE_WCCP:
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/* WCCP2 puts an extra 4 octets into the header, but uses the same
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encapsulation type; if it looks as if the first octet of the packet
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isn't the beginning of an IPv4 header, assume it's WCCP2. */
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if ((tvb_get_guint8(tvb, offset + 2 + 2) & 0xF0) != 0x40) {
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is_wccp2 = TRUE;
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}
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break;
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}
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/* Per README.developer, section 1.2, we must call subdissectors regardless
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* of whether "tree" is NULL or not. That is done below using
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* call_dissector(), but since the next_tvb must begin at the correct offset,
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* it's easier and more readable to always enter this block in order to
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* compute the correct offset to pass to tvb_new_subset_remaining().
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*/
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if (1) {
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ti = proto_tree_add_protocol_format(tree, proto_gre, tvb, offset, -1, "Generic Routing Encapsulation (%s)",
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val_to_str(type, gre_typevals, "0x%04X - unknown"));
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gre_tree = proto_item_add_subtree(ti, ett_gre);
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it_flags = proto_tree_add_item(gre_tree, hf_gre_flags_and_version, tvb, offset, 2, ENC_BIG_ENDIAN);
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fv_tree = proto_item_add_subtree(it_flags, ett_gre_flags);
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proto_tree_add_item(fv_tree, hf_gre_flags_checksum, tvb, offset, 2, ENC_BIG_ENDIAN);
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proto_tree_add_item(fv_tree, hf_gre_flags_routing, tvb, offset, 2, ENC_BIG_ENDIAN);
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proto_tree_add_item(fv_tree, hf_gre_flags_key, tvb, offset, 2, ENC_BIG_ENDIAN);
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proto_tree_add_item(fv_tree, hf_gre_flags_sequence_number, tvb, offset, 2, ENC_BIG_ENDIAN);
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proto_tree_add_item(fv_tree, hf_gre_flags_strict_source_route, tvb, offset, 2, ENC_BIG_ENDIAN);
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proto_tree_add_item(fv_tree, hf_gre_flags_recursion_control, tvb, offset, 2, ENC_BIG_ENDIAN);
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/* RFC2637 Section 4.1 : Enhanced GRE Header */
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if (is_ppp) {
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proto_tree_add_item(fv_tree, hf_gre_flags_ack, tvb, offset, 2, ENC_BIG_ENDIAN);
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proto_tree_add_item(fv_tree, hf_gre_flags_reserved_ppp, tvb, offset, 2, ENC_BIG_ENDIAN);
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}
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else {
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proto_tree_add_item(fv_tree, hf_gre_flags_reserved, tvb, offset, 2, ENC_BIG_ENDIAN);
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}
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proto_tree_add_item(fv_tree, hf_gre_flags_version, tvb, offset, 2, ENC_BIG_ENDIAN);
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offset += 2;
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proto_tree_add_item(gre_tree, hf_gre_proto, tvb, offset, 2, ENC_BIG_ENDIAN);
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offset += 2;
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if (flags_and_ver & GRE_CHECKSUM || flags_and_ver & GRE_ROUTING) {
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guint length, reported_length;
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vec_t cksum_vec[1];
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/* Checksum check !... */
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length = tvb_captured_length(tvb);
|
|
reported_length = tvb_reported_length(tvb);
|
|
/* The Checksum Present bit is set, and the packet isn't part of a
|
|
fragmented datagram and isn't truncated, so we can checksum it. */
|
|
if ((flags_and_ver & GRE_CHECKSUM) && !pinfo->fragmented && length >= reported_length) {
|
|
SET_CKSUM_VEC_TVB(cksum_vec[0], tvb, 0, reported_length);
|
|
proto_tree_add_checksum(gre_tree, tvb, offset, hf_gre_checksum, hf_gre_checksum_status, &ei_gre_checksum_incorrect, pinfo, in_cksum(cksum_vec, 1),
|
|
ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY|PROTO_CHECKSUM_IN_CKSUM);
|
|
} else {
|
|
proto_tree_add_checksum(gre_tree, tvb, offset, hf_gre_checksum, hf_gre_checksum_status, &ei_gre_checksum_incorrect, pinfo, 0,
|
|
ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
|
|
}
|
|
offset += 2;
|
|
|
|
proto_tree_add_item(gre_tree, hf_gre_offset, tvb, offset, 2, ENC_BIG_ENDIAN);
|
|
offset += 2;
|
|
}
|
|
|
|
if (flags_and_ver & GRE_KEY) {
|
|
/* RFC2637 Section 4.1 : Enhanced GRE Header */
|
|
if (is_ppp && type!=ETHERTYPE_CDMA2000_A10_UBS) {
|
|
|
|
proto_tree_add_item(gre_tree, hf_gre_key_payload_length, tvb, offset, 2, ENC_BIG_ENDIAN);
|
|
offset += 2;
|
|
|
|
proto_tree_add_item(gre_tree, hf_gre_key_call_id, tvb, offset, 2, ENC_BIG_ENDIAN);
|
|
offset += 2;
|
|
}
|
|
else {
|
|
proto_tree_add_item(gre_tree, hf_gre_key, tvb, offset, 4, ENC_BIG_ENDIAN);
|
|
offset += 4;
|
|
}
|
|
}
|
|
if (flags_and_ver & GRE_SEQUENCE) {
|
|
|
|
proto_tree_add_item(gre_tree, hf_gre_sequence_number , tvb, offset, 4, ENC_BIG_ENDIAN);
|
|
offset += 4;
|
|
}
|
|
if (is_ppp && (flags_and_ver & GRE_ACK)) {
|
|
|
|
proto_tree_add_item(gre_tree, hf_gre_ack_number , tvb, offset, 4, ENC_BIG_ENDIAN);
|
|
offset += 4;
|
|
}
|
|
if (flags_and_ver & GRE_ROUTING) {
|
|
proto_item *it_routing;
|
|
proto_tree *r_tree;
|
|
for (;;) {
|
|
|
|
it_routing = proto_tree_add_item(gre_tree, hf_gre_routing, tvb, offset, -1, ENC_NA);
|
|
r_tree = proto_item_add_subtree(ti, ett_gre_routing);
|
|
|
|
sre_af = tvb_get_ntohs(tvb, offset);
|
|
proto_tree_add_item(r_tree, hf_gre_routing_address_family , tvb, offset, 2, ENC_BIG_ENDIAN);
|
|
offset += 2;
|
|
|
|
proto_tree_add_item(r_tree, hf_gre_routing_sre_offset , tvb, offset, 1, ENC_BIG_ENDIAN);
|
|
offset += 1;
|
|
|
|
sre_length = tvb_get_guint8(tvb, offset);
|
|
proto_tree_add_item(r_tree, hf_gre_routing_sre_length , tvb, offset, 1, ENC_BIG_ENDIAN);
|
|
offset += 1;
|
|
|
|
proto_item_set_len(it_routing, 2 + 1 +1 + sre_length);
|
|
if (sre_af == 0 && sre_length == 0)
|
|
break;
|
|
|
|
proto_tree_add_item(r_tree, hf_gre_routing_information , tvb, offset, sre_length, ENC_NA);
|
|
offset += sre_length;
|
|
}
|
|
}
|
|
|
|
if (type == GRE_WCCP && is_wccp2) {
|
|
dissect_gre_wccp2_redirect_header(tvb, offset, gre_tree);
|
|
offset += 4;
|
|
}
|
|
if (type == ETHERTYPE_3GPP2) {
|
|
offset = dissect_gre_3gpp2_attribs(tvb, offset, gre_tree);
|
|
}
|
|
|
|
proto_item_set_len(ti, offset);
|
|
|
|
/* If the S bit is not set, this packet might not have a payload, so
|
|
check whether there's any data left, first.
|
|
|
|
XXX - the S bit isn't in RFC 2784, which deprecates that bit
|
|
and some other bits in RFC 1701 and says that they should be
|
|
zero for RFC 2784-compliant GRE; as such, the absence of the
|
|
S bit doesn't necessarily mean there's no payload. */
|
|
if (!(flags_and_ver & GRE_SEQUENCE)) {
|
|
if (tvb_reported_length_remaining(tvb, offset) <= 0)
|
|
return offset; /* no payload */
|
|
}
|
|
next_tvb = tvb_new_subset_remaining(tvb, offset);
|
|
pinfo->flags.in_gre_pkt = TRUE;
|
|
if (!dissector_try_uint_new(gre_dissector_table, type, next_tvb, pinfo, tree, TRUE, &flags_and_ver))
|
|
call_data_dissector(next_tvb, pinfo, gre_tree);
|
|
}
|
|
return tvb_captured_length(tvb);
|
|
}
|
|
|
|
|
|
void
|
|
proto_register_gre(void)
|
|
{
|
|
static hf_register_info hf[] = {
|
|
{ &hf_gre_proto,
|
|
{ "Protocol Type", "gre.proto",
|
|
FT_UINT16, BASE_HEX, VALS(gre_typevals), 0x0,
|
|
"The protocol that is GRE encapsulated", HFILL }
|
|
},
|
|
{ &hf_gre_flags_and_version,
|
|
{ "Flags and Version", "gre.flags_and_version",
|
|
FT_UINT16, BASE_HEX, NULL, 0x0,
|
|
"The GRE flags are encoded in the first two octets", HFILL }
|
|
},
|
|
{ &hf_gre_flags_checksum,
|
|
{ "Checksum Bit", "gre.flags.checksum",
|
|
FT_BOOLEAN, 16, TFS(&tfs_yes_no), GRE_CHECKSUM,
|
|
"Indicates if the Checksum field is present", HFILL }
|
|
},
|
|
{ &hf_gre_flags_routing,
|
|
{ "Routing Bit", "gre.flags.routing",
|
|
FT_BOOLEAN, 16, TFS(&tfs_yes_no), GRE_ROUTING,
|
|
"Indicates if the Routing and Checksum/Offset field are present", HFILL }
|
|
},
|
|
{ &hf_gre_flags_key,
|
|
{ "Key Bit", "gre.flags.key",
|
|
FT_BOOLEAN, 16, TFS(&tfs_yes_no), GRE_KEY,
|
|
"Indicates if the Key field is present", HFILL }
|
|
},
|
|
{ &hf_gre_flags_sequence_number,
|
|
{ "Sequence Number Bit", "gre.flags.sequence_number",
|
|
FT_BOOLEAN, 16, TFS(&tfs_yes_no), GRE_SEQUENCE,
|
|
"Indicates if the Sequence Number field is present", HFILL }
|
|
},
|
|
{ &hf_gre_flags_strict_source_route,
|
|
{ "Strict Source Route Bit", "gre.flags.strict_source_route",
|
|
FT_BOOLEAN, 16, TFS(&tfs_yes_no), GRE_STRICTSOURCE,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_flags_recursion_control,
|
|
{ "Recursion control", "gre.flags.recursion_control",
|
|
FT_UINT16, BASE_DEC, NULL, GRE_RECURSION,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_flags_ack,
|
|
{ "Acknowledgment", "gre.flags.ack",
|
|
FT_BOOLEAN, 16, TFS(&tfs_yes_no), GRE_ACK,
|
|
"Indicates if the packet contains an Acknowledgment Number to be used for acknowledging previously transmitted data", HFILL }
|
|
},
|
|
{ &hf_gre_flags_reserved,
|
|
{ "Flags (Reserved)", "gre.flags.reserved",
|
|
FT_UINT16, BASE_DEC, NULL, GRE_RESERVED,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_flags_reserved_ppp,
|
|
{ "Flags (Reserved)", "gre.flags.reserved",
|
|
FT_UINT16, BASE_DEC, NULL, GRE_RESERVED_PPP,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_flags_version,
|
|
{ "Version", "gre.flags.version",
|
|
FT_UINT16, BASE_DEC, VALS(gre_version), GRE_VERSION,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_checksum,
|
|
{ "Checksum", "gre.checksum",
|
|
FT_UINT16, BASE_HEX, NULL, 0x0,
|
|
"The Checksum field contains the IP (one's complement) checksum of the GRE header and the payload packet", HFILL }
|
|
},
|
|
{ &hf_gre_checksum_status,
|
|
{ "Checksum Status", "gre.checksum.status",
|
|
FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_offset,
|
|
{ "Offset", "gre.offset",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
"The offset field indicates the octet offset from the start of the Routing field to the first octet of the active Source Route Entry to be examined", HFILL }
|
|
},
|
|
{ &hf_gre_key,
|
|
{ "Key", "gre.key",
|
|
FT_UINT32, BASE_HEX, NULL, 0x0,
|
|
"The Key field contains a four octet number which was inserted by the encapsulator", HFILL }
|
|
},
|
|
{ &hf_gre_key_payload_length,
|
|
{ "Payload Length", "gre.key.payload_length",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
"Size of the payload, not including the GRE header", HFILL }
|
|
},
|
|
{ &hf_gre_key_call_id,
|
|
{ "Call ID", "gre.key.call_id",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
"Contains the Peer's Call ID for the session to which this packet belongs.", HFILL }
|
|
},
|
|
{ &hf_gre_sequence_number,
|
|
{ "Sequence Number", "gre.sequence_number",
|
|
FT_UINT32, BASE_DEC, NULL, 0x0,
|
|
"The Sequence Number field contains an unsigned 32 bit integer which is inserted by the encapsulator", HFILL }
|
|
},
|
|
{ &hf_gre_ack_number,
|
|
{ "Acknowledgment Number", "gre.ack_number",
|
|
FT_UINT32, BASE_DEC, NULL, 0x0,
|
|
"Contains the sequence number of the highest numbered GRE packet received by the sending peer for this user session", HFILL }
|
|
},
|
|
{ &hf_gre_routing,
|
|
{ "Routing", "gre.routing",
|
|
FT_NONE, BASE_NONE, NULL, 0x0,
|
|
"The Routing field is a list of Source Route Entries (SREs)", HFILL }
|
|
},
|
|
{ &hf_gre_routing_address_family,
|
|
{ "Address Family", "gre.routing.address_family",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
"The Address Family field contains a two octet value which indicates the syntax and semantics of the Routing Information field", HFILL }
|
|
},
|
|
{ &hf_gre_routing_sre_offset,
|
|
{ "SRE Offset", "gre.routing.sre_offset",
|
|
FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
"The Address Family field contains a two octet value which indicates the syntax and semantics of the Routing Information field", HFILL }
|
|
},
|
|
{ &hf_gre_routing_sre_length,
|
|
{ "SRE Length", "gre.routing.src_length",
|
|
FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
"The SRE Length field contains the number of octets in the SRE", HFILL }
|
|
},
|
|
{ &hf_gre_routing_information,
|
|
{ "Routing Information", "gre.routing.information",
|
|
FT_BYTES, BASE_NONE, NULL, 0x0,
|
|
"The Routing Information field contains data which may be used in routing this packet", HFILL }
|
|
},
|
|
{ &hf_gre_3gpp2_attrib,
|
|
{ "3GPP2 Attributes", "gre.3gpp2_attrib",
|
|
FT_NONE, BASE_NONE, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_3gpp2_attrib_id,
|
|
{ "Type", "gre.3gpp2_attrib_id",
|
|
FT_UINT8, BASE_HEX, VALS(gre_3gpp2_attrib_id_vals), 0x7f,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_3gpp2_attrib_length,
|
|
{ "Length", "gre.3gpp2_attrib_length",
|
|
FT_UINT8, BASE_HEX, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_3gpp2_sdi,
|
|
{ "SDI/DOS", "gre.3gpp2_sdi",
|
|
FT_BOOLEAN, 16, TFS(&gre_3gpp2_sdi_val), 0x8000,
|
|
"Short Data Indicator(SDI)/Data Over Signaling (DOS)", HFILL }
|
|
},
|
|
{ &hf_gre_3gpp2_fci,
|
|
{ "Flow Control Indicator", "gre.3gpp2_fci",
|
|
FT_BOOLEAN, 16, TFS(&gre_3gpp2_fci_val), 0x8000,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_3gpp2_di,
|
|
{ "Duration Indicator", "gre.3gpp2_di",
|
|
FT_BOOLEAN, 16, TFS(&gre_3gpp2_di_val), 0x4000,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_3gpp2_flow_disc,
|
|
{ "Flow ID", "gre.ggp2_flow_disc",
|
|
FT_BYTES, BASE_NONE, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_3gpp2_seg,
|
|
{ "Type", "gre.ggp2_3gpp2_seg",
|
|
FT_UINT16, BASE_HEX, VALS(gre_3gpp2_seg_vals), 0xc000,
|
|
NULL, HFILL }
|
|
},
|
|
|
|
{ &hf_gre_wccp_redirect_header,
|
|
{ "Redirect Header", "gre.wccp.redirect_header",
|
|
FT_NONE, BASE_NONE, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_wccp_dynamic_service,
|
|
{ "Dynamic Service", "gre.wccp.dynamic_service",
|
|
FT_BOOLEAN, 8, TFS(&gre_wccp_dynamic_service_val), 0x01,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_wccp_alternative_bucket_used,
|
|
{ "Alternative bucket used", "gre.wccp.alternative_bucket_used",
|
|
FT_BOOLEAN, 8, TFS(&gre_wccp_alternative_bucket_used_val), 0x02,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_wccp_redirect_header_valid,
|
|
{ "WCCP Redirect header is valid", "gre.wccp.redirect_header_valid",
|
|
FT_BOOLEAN, 8, TFS(&gre_wccp_redirect_header_valid_val), 0x04,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_gre_wccp_service_id,
|
|
{ "Service ID", "gre.wccp.service_id",
|
|
FT_UINT8, BASE_DEC, VALS(service_id_vals), 0x00,
|
|
"Service Group identifier", HFILL }
|
|
},
|
|
{ &hf_gre_wccp_alternative_bucket,
|
|
{ "Alternative Bucket", "gre.wccp.alternative_bucket",
|
|
FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
"Alternative bucket index used to redirect the packet.", HFILL }
|
|
},
|
|
{ &hf_gre_wccp_primary_bucket,
|
|
{ "Primary Bucket", "gre.wccp.primary_bucket",
|
|
FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
"Primary bucket index used to redirect the packet.", HFILL }
|
|
},
|
|
};
|
|
static gint *ett[] = {
|
|
&ett_gre,
|
|
&ett_gre_flags,
|
|
&ett_gre_routing,
|
|
&ett_gre_wccp2_redirect_header,
|
|
&ett_3gpp2_attribs,
|
|
&ett_3gpp2_attr,
|
|
};
|
|
|
|
|
|
static ei_register_info ei[] = {
|
|
{ &ei_gre_checksum_incorrect, { "gre.checksum.incorrect", PI_PROTOCOL, PI_WARN, "Incorrect GRE Checksum", EXPFILL }},
|
|
};
|
|
|
|
expert_module_t* expert_gre;
|
|
|
|
proto_gre = proto_register_protocol("Generic Routing Encapsulation",
|
|
"GRE", "gre");
|
|
proto_register_field_array(proto_gre, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
expert_gre = expert_register_protocol(proto_gre);
|
|
expert_register_field_array(expert_gre, ei, array_length(ei));
|
|
|
|
/*
|
|
* Dissector table.
|
|
*
|
|
* XXX - according to
|
|
*
|
|
* https://www.iana.org/assignments/gre-parameters/gre-parameters.xhtml#gre-parameters-1
|
|
*
|
|
* these are just Ethertypes; should we use "gre.proto" only for
|
|
* protocols *not* registered as Ethertypes, such as those listed
|
|
* in the table in "Current List of Protocol Types" in RFC 1701
|
|
* ("For historical reasons, a number of other values have been
|
|
* used for some protocols."), and for protocols encapsulated in GRE
|
|
* differently from the way they're encapsulated over LAN protocols
|
|
* (for example, Cisco MetaData), and if we don't get a match there,
|
|
* use the "ethertype" table?
|
|
*
|
|
* And should we also somehow do something similar for mapping values
|
|
* to strings, falling back on etype_vals?
|
|
*/
|
|
gre_dissector_table = register_dissector_table("gre.proto",
|
|
"GRE protocol type", proto_gre, FT_UINT16, BASE_HEX);
|
|
}
|
|
|
|
void
|
|
proto_reg_handoff_gre(void)
|
|
{
|
|
dissector_handle_t gre_handle;
|
|
capture_dissector_handle_t gre_cap_handle;
|
|
|
|
gre_handle = create_dissector_handle(dissect_gre, proto_gre);
|
|
dissector_add_uint("ip.proto", IP_PROTO_GRE, gre_handle);
|
|
dissector_add_uint("udp.port", GRE_IN_UDP_PORT, gre_handle);
|
|
gre_cap_handle = create_capture_dissector_handle(capture_gre, proto_gre);
|
|
capture_dissector_add_uint("ip.proto", IP_PROTO_GRE, gre_cap_handle);
|
|
}
|
|
|
|
/*
|
|
* Editor modelines - https://www.wireshark.org/tools/modelines.html
|
|
*
|
|
* Local variables:
|
|
* c-basic-offset: 4
|
|
* tab-width: 8
|
|
* indent-tabs-mode: nil
|
|
* End:
|
|
*
|
|
* vi: set shiftwidth=4 tabstop=8 expandtab:
|
|
* :indentSize=4:tabSize=8:noTabs=true:
|
|
*/
|