/* packet-stun.c * Routines for Session Traversal Utilities for NAT (STUN) dissection * Copyright 2003, Shiang-Ming Huang * Copyright 2006, Marc Petit-Huguenin * Copyright 2007-2008, 8x8 Inc. * Copyright 2008, Gael Breard * Copyright 2013, Media5 Corporation, David Bergeron * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * * Please refer to the following specs for protocol detail: * - RFC 5389, formerly draft-ietf-behave-rfc3489bis-18 * - RFC 5245, formerly draft-ietf-mmusic-ice-19 * - RFC 5780, formerly draft-ietf-behave-nat-behavior-discovery-08 * - RFC 5766, formerly draft-ietf-behave-turn-16 * - draft-ietf-behave-turn-ipv6-11 * - RFC 3489, http://www.faqs.org/rfcs/rfc3489.html (Addition of deprecated attributes for diagnostics purpose) * - RFC 6062 * * From MS (Lync) * MS-TURN: Traversal Using Relay NAT (TURN) Extensions http://msdn.microsoft.com/en-us/library/cc431507.aspx * MS-ICE2BWN: Interactive Connectivity Establishment (ICE) 2.0 Bandwidth Management Extensions http://msdn.microsoft.com/en-us/library/ff595756.aspx * MS-TURNBWM: Traversal using Relay NAT (TURN) Bandwidth Management Extensions http://msdn.microsoft.com/en-us/library/ff595670.aspx * MS-ICE2: Interactive Connectivity Establishment ICE Extensions 2.0 http://msdn.microsoft.com/en-us/library/office/cc431504.aspx */ #include "config.h" #include #include #include "packet-tcp.h" void proto_register_stun(void); void proto_reg_handoff_stun(void); /* heuristic subdissectors */ static heur_dissector_list_t heur_subdissector_list; /* stun dissector handles */ static dissector_handle_t data_handle; static dissector_handle_t stun_tcp_handle; static dissector_handle_t stun_udp_handle; /* Initialize the protocol and registered fields */ static int proto_stun = -1; static int hf_stun_channel = -1; static int hf_stun_tcp_frame_length = -1; static int hf_stun_type = -1; static int hf_stun_type_class = -1; static int hf_stun_type_method = -1; static int hf_stun_type_method_assignment = -1; static int hf_stun_length = -1; static int hf_stun_cookie = -1; static int hf_stun_id = -1; static int hf_stun_attributes = -1; static int hf_stun_response_in = -1; static int hf_stun_response_to = -1; static int hf_stun_time = -1; static int hf_stun_duplicate = -1; static int hf_stun_attr = -1; static int hf_stun_att_type = -1; /* STUN attribute fields */ static int hf_stun_att_length = -1; static int hf_stun_att_family = -1; static int hf_stun_att_type_comprehension = -1; static int hf_stun_att_type_assignment = -1; static int hf_stun_att_ipv4 = -1; static int hf_stun_att_ipv6 = -1; static int hf_stun_att_port = -1; static int hf_stun_att_username = -1; static int hf_stun_att_password = -1; static int hf_stun_att_padding = -1; static int hf_stun_att_hmac = -1; static int hf_stun_att_crc32 = -1; static int hf_stun_att_error_class = -1; static int hf_stun_att_error_number = -1; static int hf_stun_att_error_reason = -1; static int hf_stun_att_realm = -1; static int hf_stun_att_nonce = -1; static int hf_stun_att_unknown = -1; static int hf_stun_att_xor_ipv4 = -1; static int hf_stun_att_xor_ipv6 = -1; static int hf_stun_att_xor_port = -1; static int hf_stun_att_icmp_type = -1; static int hf_stun_att_icmp_code = -1; static int hf_stun_att_software = -1; static int hf_stun_att_priority = -1; static int hf_stun_att_tie_breaker = -1; static int hf_stun_att_change_ip = -1; static int hf_stun_att_change_port = -1; static int hf_stun_att_cache_timeout = -1; static int hf_stun_att_token = -1; static int hf_stun_att_reserve_next = -1; static int hf_stun_att_reserved = -1; static int hf_stun_att_value = -1; static int hf_stun_att_transp = -1; static int hf_stun_att_magic_cookie = -1; static int hf_stun_att_bandwidth = -1; static int hf_stun_att_lifetime = -1; static int hf_stun_att_channelnum = -1; static int hf_stun_att_ms_version = -1; static int hf_stun_att_ms_connection_id = -1; static int hf_stun_att_ms_sequence_number = -1; static int hf_stun_att_ms_stream_type = -1; static int hf_stun_att_ms_service_quality = -1; static int hf_stun_att_ms_foundation = -1; static int hf_stun_att_bandwidth_acm_type = -1; static int hf_stun_att_bandwidth_rsv_id = -1; static int hf_stun_att_bandwidth_rsv_amount_misb = -1; static int hf_stun_att_bandwidth_rsv_amount_masb = -1; static int hf_stun_att_bandwidth_rsv_amount_mirb = -1; static int hf_stun_att_bandwidth_rsv_amount_marb = -1; static int hf_stun_att_address_rp_a = -1; static int hf_stun_att_address_rp_b = -1; static int hf_stun_att_address_rp_rsv1 = -1; static int hf_stun_att_address_rp_rsv2 = -1; static int hf_stun_att_address_rp_masb = -1; static int hf_stun_att_address_rp_marb = -1; static int hf_stun_att_sip_dialog_id = -1; static int hf_stun_att_sip_call_id = -1; static int hf_stun_att_lp_peer_location = -1; static int hf_stun_att_lp_self_location = -1; static int hf_stun_att_lp_federation = -1; /* Structure containing transaction specific information */ typedef struct _stun_transaction_t { guint32 req_frame; guint32 rep_frame; nstime_t req_time; } stun_transaction_t; /* Structure containing conversation specific information */ typedef struct _stun_conv_info_t { wmem_tree_t *transaction_pdus; } stun_conv_info_t; /* Message classes */ #define REQUEST 0x0000 #define INDICATION 0x0001 #define RESPONSE 0x0002 #define ERROR_RESPONSE 0x0003 /* Methods */ #define BINDING 0x0001 /* draft-ietf-behave-rfc3489bis-17 */ #define ALLOCATE 0x0003 /* draft-ietf-behave-turn-10*/ #define REFRESH 0x0004 /* draft-ietf-behave-turn-10*/ #define CHANNELBIND 0x0009 /* draft-ietf-behave-turn-10*/ #define CREATE_PERMISSION 0x0008 /* draft-ietf-behave-turn-10 */ /* Indications */ #define SEND 0x0006 /* draft-ietf-behave-turn-10*/ #define DATA_IND 0x0007 /* draft-ietf-behave-turn-10*/ /* TCP specific */ #define CONNECT 0x000a /* rfc6062 */ #define CONNECTION_BIND 0x000b /* rfc6062 */ #define CONNECTION_ATTEMPT 0x000c /* rfc6062 */ /* Attribute Types */ /* Comprehension-required range (0x0000-0x7FFF) */ #define MAPPED_ADDRESS 0x0001 /* draft-ietf-behave-rfc3489bis-17 */ #define RESPONSE_ADDRESS 0x0002 /* Deprecated */ #define CHANGE_REQUEST 0x0003 /* draft-ietf-behave-nat-behavior-discovery-03 */ #define SOURCE_ADDRESS 0x0004 /* Deprecated */ #define CHANGED_ADDRESS 0x0005 /* Deprecated */ #define USERNAME 0x0006 /* draft-ietf-behave-rfc3489bis-17 */ #define PASSWORD 0x0007 /* Deprecated */ #define MESSAGE_INTEGRITY 0x0008 /* draft-ietf-behave-rfc3489bis-17 */ #define ERROR_CODE 0x0009 /* draft-ietf-behave-rfc3489bis-17 */ #define UNKNOWN_ATTRIBUTES 0x000a /* draft-ietf-behave-rfc3489bis-17 */ #define REFLECTED_FROM 0x000b /* Deprecated */ #define CHANNEL_NUMBER 0x000c /* draft-ietf-behave-turn-10 */ #define LIFETIME 0x000d /* draft-ietf-behave-turn-10 */ #define MAGIC_COOKIE 0x000f /* MS-TURN / turn-08 */ #define BANDWIDTH 0x0010 /* turn-07 */ #define DESTINATION_ADDRESS 0x0011 /* MS-TURN / turn-08 */ #define XOR_PEER_ADDRESS 0x0012 /* draft-ietf-behave-turn-10 */ #define DATA 0x0013 /* draft-ietf-behave-turn-10 */ #define REALM 0x0014 /* draft-ietf-behave-rfc3489bis-17 */ #define NONCE 0x0015 /* draft-ietf-behave-rfc3489bis-17 */ #define XOR_RELAYED_ADDRESS 0x0016 /* draft-ietf-behave-turn-10 */ #define REQUESTED_ADDRESS_TYPE 0x0017 /* draft-ietf-behave-turn-ipv6-03 */ #define EVEN_PORT 0x0018 /* draft-ietf-behave-turn-10 */ #define REQUESTED_TRANSPORT 0x0019 /* draft-ietf-behave-turn-10 */ #define DONT_FRAGMENT 0x001a /* draft-ietf-behave-turn-10 */ #define XOR_MAPPED_ADDRESS 0x0020 /* draft-ietf-behave-rfc3489bis-17 */ #define RESERVATION_TOKEN 0x0022 /* draft-ietf-behave-turn-10 */ #define PRIORITY 0x0024 /* draft-ietf-mmusic-ice-19 */ #define USE_CANDIDATE 0x0025 /* draft-ietf-mmusic-ice-19 */ #define PADDING 0x0026 /* draft-ietf-behave-nat-behavior-discovery-03 */ #define XOR_RESPONSE_TARGET 0x0027 /* draft-ietf-behave-nat-behavior-discovery-03 */ #define XOR_REFLECTED_FROM 0x0028 /* draft-ietf-behave-nat-behavior-discovery-03 */ #define CONNECTION_ID 0x002a /* rfc6062 */ #define ICMP 0x0030 /* Moved from TURN to a future I-D */ /* Comprehension-optional range (0x8000-0xFFFF) */ #define MS_VERSION 0x8008 /* MS-TURN */ #define MS_XOR_MAPPED_ADDRESS 0x8020 /* MS-TURN */ #define SOFTWARE 0x8022 /* draft-ietf-behave-rfc3489bis-17 */ #define ALTERNATE_SERVER 0x8023 /* draft-ietf-behave-rfc3489bis-17 */ #define CACHE_TIMEOUT 0x8027 /* draft-ietf-behave-nat-behavior-discovery-03 */ #define FINGERPRINT 0x8028 /* draft-ietf-behave-rfc3489bis-17 */ #define ICE_CONTROLLED 0x8029 /* draft-ietf-mmusic-ice-19 */ #define ICE_CONTROLLING 0x802a /* draft-ietf-mmusic-ice-19 */ #define RESPONSE_ORIGIN 0x802b /* draft-ietf-behave-nat-behavior-discovery-03 */ #define OTHER_ADDRESS 0x802c /* draft-ietf-behave-nat-behavior-discovery-03 */ #define MS_SEQUENCE_NUMBER 0x8050 /* MS-TURN */ #define MS_CANDIDATE_IDENTIFIER 0x8054 /* MS-ICE2 */ #define MS_SERVICE_QUALITY 0x8055 /* MS-TURN */ #define BANDWIDTH_ACM 0x8056 /* MS-TURNBWM */ #define BANDWIDTH_RSV_ID 0x8057 /* MS-TURNBWM */ #define BANDWIDTH_RSV_AMOUNT 0x8058 /* MS-TURNBWM */ #define REMOTE_SITE_ADDR 0x8059 /* MS-TURNBWM */ #define REMOTE_RELAY_SITE 0x805A /* MS-TURNBWM */ #define LOCAL_SITE_ADDR 0x805B /* MS-TURNBWM */ #define LOCAL_RELAY_SITE 0x805C /* MS-TURNBWM */ #define REMOTE_SITE_ADDR_RP 0x805D /* MS-TURNBWM */ #define REMOTE_RELAY_SITE_RP 0x805E /* MS-TURNBWM */ #define LOCAL_SITE_ADDR_RP 0x805F /* MS-TURNBWM */ #define LOCAL_RELAY_SITE_RP 0x8060 /* MS-TURNBWM */ #define SIP_DIALOG_ID 0x8061 /* MS-TURNBWM */ #define SIP_CALL_ID 0x8062 /* MS-TURNBWM */ #define LOCATION_PROFILE 0x8068 /* MS-TURNBWM */ #define MS_IMPLEMENTATION_VER 0x8070 /* MS-ICE2 */ #define MS_ALT_MAPPED_ADDRESS 0x8090 /* MS-TURN */ /* Initialize the subtree pointers */ static gint ett_stun = -1; static gint ett_stun_type = -1; static gint ett_stun_att_all= -1; static gint ett_stun_att = -1; static gint ett_stun_att_type = -1; #define UDP_PORT_STUN 3478 #define TCP_PORT_STUN 3478 #define STUN_HDR_LEN 20 /* STUN message header length */ #define ATTR_HDR_LEN 4 /* STUN attribute header length */ #define CHANNEL_DATA_HDR_LEN 4 /* TURN CHANNEL-DATA Message hdr length */ #define MIN_HDR_LEN 4 #define TCP_FRAME_COOKIE_LEN 10 /* min length for cookie with TCP framing */ static const value_string transportnames[] = { { 17, "UDP" }, { 6, "TCP" }, { 0, NULL } }; static const value_string classes[] = { {REQUEST , "Request"}, {INDICATION , "Indication"}, {RESPONSE , "Success Response"}, {ERROR_RESPONSE, "Error Response"}, {0x00 , NULL} }; static const value_string methods[] = { {BINDING , "Binding"}, {ALLOCATE , "Allocate"}, {REFRESH , "Refresh"}, {SEND , "Send"}, {DATA_IND , "Data"}, {CREATE_PERMISSION , "CreatePermission"}, {CHANNELBIND , "Channel-Bind"}, {CONNECT , "Connect"}, {CONNECTION_BIND , "ConnectionBind"}, {CONNECTION_ATTEMPT, "ConnectionAttempt"}, {0x00 , NULL} }; static const value_string attributes[] = { {MAPPED_ADDRESS , "MAPPED-ADDRESS"}, {RESPONSE_ADDRESS , "RESPONSE_ADDRESS"}, {CHANGE_REQUEST , "CHANGE_REQUEST"}, {SOURCE_ADDRESS , "SOURCE_ADDRESS"}, {CHANGED_ADDRESS , "CHANGED_ADDRESS"}, {USERNAME , "USERNAME"}, {PASSWORD , "PASSWORD"}, {MESSAGE_INTEGRITY , "MESSAGE-INTEGRITY"}, {ERROR_CODE , "ERROR-CODE"}, {UNKNOWN_ATTRIBUTES , "UNKNOWN-ATTRIBUTES"}, {REFLECTED_FROM , "REFLECTED-FROM"}, {CHANNEL_NUMBER , "CHANNEL-NUMBER"}, {LIFETIME , "LIFETIME"}, {MAGIC_COOKIE , "MAGIC-COOKIE"}, {BANDWIDTH , "BANDWIDTH"}, {DESTINATION_ADDRESS , "DESTINATION-ADDRESS"}, {XOR_PEER_ADDRESS , "XOR-PEER-ADDRESS"}, {DATA , "DATA"}, {REALM , "REALM"}, {NONCE , "NONCE"}, {XOR_RELAYED_ADDRESS , "XOR-RELAYED-ADDRESS"}, {REQUESTED_ADDRESS_TYPE, "REQUESTED-ADDRESS-TYPE"}, {EVEN_PORT , "EVEN-PORT"}, {REQUESTED_TRANSPORT , "REQUESTED-TRANSPORT"}, {DONT_FRAGMENT , "DONT-FRAGMENT"}, {XOR_MAPPED_ADDRESS , "XOR-MAPPED-ADDRESS"}, {RESERVATION_TOKEN , "RESERVATION-TOKEN"}, {PRIORITY , "PRIORITY"}, {USE_CANDIDATE , "USE-CANDIDATE"}, {PADDING , "PADDING"}, {XOR_RESPONSE_TARGET , "XOR-RESPONSE-TARGET"}, {XOR_REFLECTED_FROM , "XOR-REFELECTED-FROM"}, {CONNECTION_ID , "CONNECTION-ID"}, {ICMP , "ICMP"}, {MS_VERSION , "MS-VERSION"}, {MS_XOR_MAPPED_ADDRESS , "XOR-MAPPED-ADDRESS"}, {SOFTWARE , "SOFTWARE"}, {ALTERNATE_SERVER , "ALTERNATE-SERVER"}, {CACHE_TIMEOUT , "CACHE-TIMEOUT"}, {FINGERPRINT , "FINGERPRINT"}, {ICE_CONTROLLED , "ICE-CONTROLLED"}, {ICE_CONTROLLING , "ICE-CONTROLLING"}, {RESPONSE_ORIGIN , "RESPONSE-ORIGIN"}, {OTHER_ADDRESS , "OTHER-ADDRESS"}, {MS_SEQUENCE_NUMBER , "MS-SEQUENCE-NUMBER"}, {MS_CANDIDATE_IDENTIFIER, "MS-CANDIDATE-IDENTIFIER"}, {MS_SERVICE_QUALITY , "MS-SERVICE-QUALITY"}, {BANDWIDTH_ACM , "Bandwidth Admission Control Message"}, {BANDWIDTH_RSV_ID , "Bandwidth Reservation Identifier"}, {BANDWIDTH_RSV_AMOUNT , "Bandwidth Reservation Amount"}, {REMOTE_SITE_ADDR , "Remote Site Address"}, {REMOTE_RELAY_SITE , "Remote Relay Site Address"}, {LOCAL_SITE_ADDR , "Local Site Address"}, {LOCAL_RELAY_SITE , "Local Relay Site Address"}, {REMOTE_SITE_ADDR_RP , "Remote Site Address Response"}, {REMOTE_RELAY_SITE_RP , "Remote Relay Site Address Response"}, {LOCAL_SITE_ADDR_RP , "Local Site Address Response"}, {LOCAL_RELAY_SITE_RP , "Local Relay Site Address Response"}, {SIP_DIALOG_ID , "SIP Dialog Identifier"}, {SIP_CALL_ID , "SIP Call Identifier"}, {LOCATION_PROFILE , "Location Profile"}, {MS_IMPLEMENTATION_VER , "MS-IMPLEMENTATION-VERSION"}, {MS_ALT_MAPPED_ADDRESS , "MS-ALT-MAPPED-ADDRESS"}, {0x00 , NULL} }; static value_string_ext attributes_ext = VALUE_STRING_EXT_INIT(attributes); static const value_string assignments[] = { {0x0000, "IETF Review"}, {0x0001, "Designated Expert"}, {0x00, NULL} }; static const value_string comprehensions[] = { {0x0000, "Required"}, {0x0001, "Optional"}, {0x00 , NULL} }; static const value_string attributes_reserve_next[] = { {0, "No reservation"}, {1, "Reserve next port number"}, {0x00, NULL} }; #if 0 static const value_string attributes_properties_p[] = { {0, "All allocation"}, {1, "Preserving allocation"}, {0x00, NULL} }; #endif static const value_string attributes_family[] = { {0x0001, "IPv4"}, {0x0002, "IPv6"}, {0x00, NULL} }; /* http://www.iana.org/assignments/stun-parameters/stun-parameters.xhtml#stun-parameters-6 (2015-06-12)*/ static const value_string error_code[] = { {274, "Disable Candidate"}, /* MS-ICE2BWN */ {275, "Disable Candidate Pair"}, /* MS-ICE2BWN */ {300, "Try Alternate"}, /* rfc3489bis-15 */ {400, "Bad Request"}, /* rfc3489bis-15 */ {401, "Unauthorized"}, /* rfc3489bis-15 */ {403, "Forbidden"}, /* rfc5766 */ {420, "Unknown Attribute"}, /* rfc3489bis-15 */ {437, "Allocation Mismatch"}, /* turn-07 */ {438, "Stale Nonce"}, /* rfc3489bis-15 */ {439, "Wrong Credentials"}, /* turn-07 - collision 38=>39 */ {440, "Address Family not Supported"}, /* turn-ipv6-04 */ {441, "Wrong Credentials"}, /* rfc5766 */ {442, "Unsupported Transport Protocol"}, /* turn-07 */ {443, "Peer Address Family Mismatch"}, /* rfc6156 */ {446, "Connection Already Exists"}, /* rfc6062 */ {447, "Connection Timeout or Failure"}, /* rfc6062 */ {481, "Connection does not exist"}, /* nat-behavior-discovery-03 */ {486, "Allocation Quota Reached"}, /* turn-07 */ {487, "Role Conflict"}, /* rfc5245 */ {500, "Server Error"}, /* rfc3489bis-15 */ {503, "Service Unavailable"}, /* nat-behavior-discovery-03 */ {507, "Insufficient Bandwidth Capacity"}, /* turn-07 */ {508, "Insufficient Port Capacity"}, /* turn-07 */ {600, "Global Failure"}, {0x00, NULL} }; static value_string_ext error_code_ext = VALUE_STRING_EXT_INIT(error_code); static const value_string ms_version_vals[] = { {0x00000001, "ICE"}, {0x00000002, "MS-ICE2"}, {0x00000003, "MS-ICE2 with SHA256"}, {0x00000004, "MS-ICE2 with SHA256 and IPv6"}, {0x00, NULL} }; static const value_string ms_stream_type_vals[] = { {0x0001, "Audio"}, {0x0002, "Video"}, {0x0003, "Supplemental Video"}, {0x0004, "Data"}, {0x00, NULL} }; static const value_string ms_service_quality_vals[] = { {0x0000, "Best effort delivery"}, {0x0001, "Reliable delivery"}, {0x00, NULL} }; static const value_string bandwidth_acm_type_vals[] = { {0x0000, "Reservation Check"}, {0x0001, "Reservation Commit"}, {0x0002, "Reservation Update"}, {0x00, NULL} }; static const value_string location_vals[] = { {0x00, "Unknown"}, {0x01, "Internet"}, {0x02, "Intranet"}, {0x00, NULL} }; static const value_string federation_vals[] = { {0x00, "No Federation"}, {0x01, "Enterprise Federation"}, {0x02, "Public Cloud Federation"}, {0x00, NULL} }; static guint get_stun_message_len(packet_info *pinfo _U_, tvbuff_t *tvb, int offset, void *data _U_) { guint16 type; guint length; guint captured_length = tvb_captured_length(tvb); if ((captured_length >= TCP_FRAME_COOKIE_LEN) && (tvb_get_ntohl(tvb, 6) == 0x2112a442)) { /* The magic cookie is off by two, this appears to be RFC4751 framing */ return (tvb_get_ntohs(tvb, 0) + 2); } type = tvb_get_ntohs(tvb, offset); length = tvb_get_ntohs(tvb, offset+2); if (type & 0xC000) { /* two first bits not NULL => should be a channel-data message */ /* Note: For TCP the message is padded to a 4 byte boundary */ return (length + CHANNEL_DATA_HDR_LEN +3) & ~0x3; } else { /* Normal STUN message */ return length + STUN_HDR_LEN; } } /* * XXX: why is this done in this file by the STUN dissector? Why don't we * re-use the packet-turnchannel.c's dissect_turnchannel_message() function? */ static int dissect_stun_message_channel_data(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint16 msg_type _U_, guint msg_length _U_) { tvbuff_t *next_tvb; heur_dtbl_entry_t *hdtbl_entry; /* XXX: a TURN ChannelData message is not actually a STUN message. */ col_set_str(pinfo->cinfo, COL_PROTOCOL, "STUN"); col_set_str(pinfo->cinfo, COL_INFO, "ChannelData TURN Message"); if (tree) { proto_item *ti; proto_tree *stun_tree; ti = proto_tree_add_item( tree, proto_stun, tvb, 0, CHANNEL_DATA_HDR_LEN, ENC_NA); proto_item_append_text(ti, ", TURN ChannelData Message"); stun_tree = proto_item_add_subtree(ti, ett_stun); proto_tree_add_item(stun_tree, hf_stun_channel, tvb, 0, 2, ENC_BIG_ENDIAN); proto_tree_add_item(stun_tree, hf_stun_length, tvb, 2, 2, ENC_BIG_ENDIAN); } next_tvb = tvb_new_subset_remaining(tvb, CHANNEL_DATA_HDR_LEN); if (!dissector_try_heuristic(heur_subdissector_list, next_tvb, pinfo, tree, &hdtbl_entry, NULL)) { call_dissector_only(data_handle, next_tvb, pinfo, tree, NULL); } return tvb_reported_length(tvb); } static int dissect_stun_message(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gboolean heur_check, gboolean is_udp) { guint captured_length; guint16 msg_type; guint msg_length; proto_item *ti; proto_tree *stun_tree; proto_tree *stun_type_tree; proto_tree *att_all_tree; proto_tree *att_type_tree; proto_tree *att_tree = NULL; guint16 msg_type_method; guint16 msg_type_class; const char *msg_class_str; const char *msg_method_str; guint16 att_type; guint16 att_length, clear_port; guint32 clear_ip; guint i; guint offset; guint magic_cookie_first_word; guint tcp_framing_offset; conversation_t *conversation=NULL; stun_conv_info_t *stun_info; stun_transaction_t *stun_trans; wmem_tree_key_t transaction_id_key[2]; guint32 transaction_id[3]; heur_dtbl_entry_t *hdtbl_entry; guint reported_length; gboolean is_turn = FALSE; /* * Check if the frame is really meant for us. */ /* First, make sure we have enough data to do the check. */ captured_length = tvb_captured_length(tvb); reported_length = tvb_reported_length(tvb); if (captured_length < MIN_HDR_LEN) return 0; tcp_framing_offset = 0; if ((!is_udp) && (captured_length >= TCP_FRAME_COOKIE_LEN) && (tvb_get_ntohl(tvb, 6) == 0x2112a442)) { /* we found ICE TCP framing according to RFC 4571 */ tcp_framing_offset = 2; } msg_type = tvb_get_ntohs(tvb, tcp_framing_offset + 0); msg_length = tvb_get_ntohs(tvb, tcp_framing_offset + 2); /* TURN ChannelData message ? */ if (msg_type & 0xC000) { /* two first bits not NULL => should be a channel-data message */ /* * If the packet is being dissected through heuristics, we never match * TURN ChannelData because the heuristics are otherwise rather weak. * Instead we have to have seen another TURN message type on the same * 5-tuple, and then set that conversation for non-heuristic STUN dissection. */ if (heur_check) return 0; if (msg_type == 0xFFFF) return 0; /* note that padding is only mandatory over streaming protocols */ if (is_udp) { if (reported_length != msg_length + CHANNEL_DATA_HDR_LEN && reported_length != ((msg_length + CHANNEL_DATA_HDR_LEN + 3) & ~0x3)) return 0; } else { /* TCP */ if (reported_length != ((msg_length + CHANNEL_DATA_HDR_LEN + 3) & ~0x3)) return 0; } /* XXX: why don't we invoke the turnchannel dissector instead? */ return dissect_stun_message_channel_data(tvb, pinfo, tree, msg_type, msg_length); } /* Normal STUN message */ if (captured_length < STUN_HDR_LEN) return 0; /* Check if it is really a STUN message */ if ( tvb_get_ntohl(tvb, tcp_framing_offset + 4) != 0x2112a442) return 0; /* check if payload enough */ if (reported_length != (msg_length + STUN_HDR_LEN + tcp_framing_offset)) return 0; /* The message seems to be a valid STUN message! */ col_set_str(pinfo->cinfo, COL_PROTOCOL, "STUN"); /* Create the transaction key which may be used to track the conversation */ transaction_id[0] = tvb_get_ntohl(tvb, tcp_framing_offset + 8); transaction_id[1] = tvb_get_ntohl(tvb, tcp_framing_offset + 12); transaction_id[2] = tvb_get_ntohl(tvb, tcp_framing_offset + 16); transaction_id_key[0].length = 3; transaction_id_key[0].key = transaction_id; transaction_id_key[1].length = 0; transaction_id_key[1].key = NULL; msg_type_class = ((msg_type & 0x0010) >> 4) | ((msg_type & 0x0100) >> 7) ; msg_type_method = (msg_type & 0x000F) | ((msg_type & 0x00E0) >> 1) | ((msg_type & 0x3E00) >> 2); switch (msg_type_method) { /* if it's a TURN method, remember that */ case ALLOCATE: case REFRESH: case SEND: case DATA_IND: case CREATE_PERMISSION: case CHANNELBIND: case CONNECT: case CONNECTION_BIND: case CONNECTION_ATTEMPT: is_turn = TRUE; break; } conversation = find_or_create_conversation(pinfo); /* * Do we already have a state structure for this conv */ stun_info = (stun_conv_info_t *)conversation_get_proto_data(conversation, proto_stun); if (!stun_info) { /* No. Attach that information to the conversation, and add * it to the list of information structures. */ stun_info = wmem_new(wmem_file_scope(), stun_conv_info_t); stun_info->transaction_pdus=wmem_tree_new(wmem_file_scope()); conversation_add_proto_data(conversation, proto_stun, stun_info); } if (!pinfo->fd->flags.visited) { if ((stun_trans = (stun_transaction_t *) wmem_tree_lookup32_array(stun_info->transaction_pdus, transaction_id_key)) == NULL) { transaction_id_key[0].length = 3; transaction_id_key[0].key = transaction_id; transaction_id_key[1].length = 0; transaction_id_key[1].key = NULL; stun_trans=wmem_new(wmem_file_scope(), stun_transaction_t); stun_trans->req_frame=0; stun_trans->rep_frame=0; stun_trans->req_time=pinfo->abs_ts; wmem_tree_insert32_array(stun_info->transaction_pdus, transaction_id_key, (void *)stun_trans); } if (msg_type_class == REQUEST) { /* This is a request */ if (stun_trans->req_frame == 0) { stun_trans->req_frame=pinfo->num; } } else { /* This is a catch-all for all non-request messages */ if (stun_trans->rep_frame == 0) { stun_trans->rep_frame=pinfo->num; } } } else { stun_trans=(stun_transaction_t *)wmem_tree_lookup32_array(stun_info->transaction_pdus, transaction_id_key); } if (!stun_trans) { /* create a "fake" pana_trans structure */ stun_trans=wmem_new(wmem_packet_scope(), stun_transaction_t); stun_trans->req_frame=0; stun_trans->rep_frame=0; stun_trans->req_time=pinfo->abs_ts; } msg_class_str = val_to_str_const(msg_type_class, classes, "Unknown"); msg_method_str = val_to_str_const(msg_type_method, methods, "Unknown"); col_add_lstr(pinfo->cinfo, COL_INFO, msg_method_str, " ", msg_class_str, COL_ADD_LSTR_TERMINATOR); offset = 0; ti = proto_tree_add_item(tree, proto_stun, tvb, offset, -1, ENC_NA); stun_tree = proto_item_add_subtree(ti, ett_stun); if (msg_type_class == REQUEST) { if (stun_trans->req_frame != pinfo->num) { proto_item *it; it=proto_tree_add_uint(stun_tree, hf_stun_duplicate, tvb, offset, 0, stun_trans->req_frame); PROTO_ITEM_SET_GENERATED(it); } if (stun_trans->rep_frame) { proto_item *it; it=proto_tree_add_uint(stun_tree, hf_stun_response_in, tvb, offset, 0, stun_trans->rep_frame); PROTO_ITEM_SET_GENERATED(it); } } else { /* Retransmission control */ if (stun_trans->rep_frame != pinfo->num) { proto_item *it; it=proto_tree_add_uint(stun_tree, hf_stun_duplicate, tvb, offset, 0, stun_trans->rep_frame); PROTO_ITEM_SET_GENERATED(it); } if (msg_type_class == RESPONSE || msg_type_class == ERROR_RESPONSE) { /* This is a response */ if (stun_trans->req_frame) { proto_item *it; nstime_t ns; it=proto_tree_add_uint(stun_tree, hf_stun_response_to, tvb, offset, 0, stun_trans->req_frame); PROTO_ITEM_SET_GENERATED(it); nstime_delta(&ns, &pinfo->abs_ts, &stun_trans->req_time); it=proto_tree_add_time(stun_tree, hf_stun_time, tvb, offset, 0, &ns); PROTO_ITEM_SET_GENERATED(it); } } } if (tcp_framing_offset) { proto_tree_add_item(stun_tree, hf_stun_tcp_frame_length, tvb, offset, 2, ENC_BIG_ENDIAN); offset += 2; } ti = proto_tree_add_uint_format_value(stun_tree, hf_stun_type, tvb, offset, 2, msg_type, "0x%04x (%s %s)", msg_type, msg_method_str, msg_class_str); stun_type_tree = proto_item_add_subtree(ti, ett_stun_type); ti = proto_tree_add_uint(stun_type_tree, hf_stun_type_class, tvb, offset, 2, msg_type); proto_item_append_text(ti, " %s (%d)", msg_class_str, msg_type_class); ti = proto_tree_add_uint(stun_type_tree, hf_stun_type_method, tvb, offset, 2, msg_type); proto_item_append_text(ti, " %s (0x%03x)", msg_method_str, msg_type_method); proto_tree_add_uint(stun_type_tree, hf_stun_type_method_assignment, tvb, offset, 2, msg_type); offset += 2; proto_tree_add_item(stun_tree, hf_stun_length, tvb, offset, 2, ENC_BIG_ENDIAN); offset += 2; proto_tree_add_item(stun_tree, hf_stun_cookie, tvb, offset, 4, ENC_NA); offset += 4; proto_tree_add_item(stun_tree, hf_stun_id, tvb, offset, 12, ENC_NA); offset += 12; /* Remember this (in host order) so we can show clear xor'd addresses */ magic_cookie_first_word = tvb_get_ntohl(tvb, tcp_framing_offset + 4); if (msg_length != 0) { const gchar *attribute_name_str; ti = proto_tree_add_item(stun_tree, hf_stun_attributes, tvb, offset, msg_length, ENC_NA); att_all_tree = proto_item_add_subtree(ti, ett_stun_att_all); while (offset < (STUN_HDR_LEN + msg_length)) { att_type = tvb_get_ntohs(tvb, offset); /* Type field in attribute header */ att_length = tvb_get_ntohs(tvb, offset+2); /* Length field in attribute header */ attribute_name_str = val_to_str_ext_const(att_type, &attributes_ext, "Unknown"); if(att_all_tree){ ti = proto_tree_add_uint_format(att_all_tree, hf_stun_attr, tvb, offset, ATTR_HDR_LEN+att_length, att_type, "%s", attribute_name_str); att_tree = proto_item_add_subtree(ti, ett_stun_att); ti = proto_tree_add_uint(att_tree, hf_stun_att_type, tvb, offset, 2, att_type); att_type_tree = proto_item_add_subtree(ti, ett_stun_att_type); proto_tree_add_uint(att_type_tree, hf_stun_att_type_comprehension, tvb, offset, 2, att_type); proto_tree_add_uint(att_type_tree, hf_stun_att_type_assignment, tvb, offset, 2, att_type); if ((offset+ATTR_HDR_LEN+att_length) > (STUN_HDR_LEN+msg_length+tcp_framing_offset)) { proto_tree_add_uint_format_value(att_tree, hf_stun_att_length, tvb, offset+2, 2, att_length, "%u (bogus, goes past the end of the message)", att_length); break; } } offset += 2; proto_tree_add_uint(att_tree, hf_stun_att_length, tvb, offset, 2, att_length); offset += 2; switch (att_type) { /* Deprecated STUN RFC3489 attributes */ case RESPONSE_ADDRESS: case SOURCE_ADDRESS: case CHANGED_ADDRESS: case REFLECTED_FROM: case DESTINATION_ADDRESS: if (att_length < 1) break; proto_tree_add_item(att_tree, hf_stun_att_reserved, tvb, offset, 1, ENC_NA); if (att_length < 2) break; proto_tree_add_item(att_tree, hf_stun_att_family, tvb, offset+1, 1, ENC_BIG_ENDIAN); if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_port, tvb, offset+2, 2, ENC_BIG_ENDIAN); switch (tvb_get_guint8(tvb, offset+1)) { case 1: if (att_length < 8) break; proto_tree_add_item(att_tree, hf_stun_att_ipv4, tvb, offset+4, 4, ENC_BIG_ENDIAN); proto_item_append_text(att_tree, " (Deprecated): %s:%d", tvb_ip_to_str(tvb, offset+4),tvb_get_ntohs(tvb,offset+2)); break; case 2: if (att_length < 20) break; proto_tree_add_item(att_tree, hf_stun_att_ipv6, tvb, offset+4, 16, ENC_NA); break; } break; /* Deprecated STUN RFC3489 attributes */ case PASSWORD: { const guint8* dep_password; proto_tree_add_item_ret_string(att_tree, hf_stun_att_password, tvb, offset, att_length, ENC_UTF_8|ENC_NA, wmem_packet_scope(), &dep_password); proto_item_append_text(att_tree, " (Deprecated): %s", dep_password); if (att_length % 4 != 0) proto_tree_add_uint(att_tree, hf_stun_att_padding, tvb, offset+att_length, 4-(att_length % 4), 4-(att_length % 4)); } break; case MAPPED_ADDRESS: case ALTERNATE_SERVER: case RESPONSE_ORIGIN: case OTHER_ADDRESS: case MS_ALT_MAPPED_ADDRESS: { const gchar *addr_str; guint16 att_port; if (att_length < 1) break; proto_tree_add_item(att_tree, hf_stun_att_reserved, tvb, offset, 1, ENC_NA); if (att_length < 2) break; proto_tree_add_item(att_tree, hf_stun_att_family, tvb, offset+1, 1, ENC_BIG_ENDIAN); if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_port, tvb, offset+2, 2, ENC_BIG_ENDIAN); att_port = tvb_get_ntohs(tvb, offset + 2); switch (tvb_get_guint8(tvb, offset+1)) { case 1: if (att_length < 8) break; addr_str = tvb_ip_to_str(tvb, offset + 4); proto_tree_add_item(att_tree, hf_stun_att_ipv4, tvb, offset+4, 4, ENC_BIG_ENDIAN); proto_item_append_text(att_tree, ": %s:%d", addr_str, att_port); col_append_fstr( pinfo->cinfo, COL_INFO, " %s: %s:%d", attribute_name_str, addr_str, att_port ); break; case 2: if (att_length < 20) break; proto_tree_add_item(att_tree, hf_stun_att_ipv6, tvb, offset+4, 16, ENC_NA); break; } break; } case CHANGE_REQUEST: if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_change_ip, tvb, offset, 4, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_change_port, tvb, offset, 4, ENC_BIG_ENDIAN); break; case USERNAME: { const guint8 *user_name_str; proto_tree_add_item_ret_string(att_tree, hf_stun_att_username, tvb, offset, att_length, ENC_UTF_8|ENC_NA, wmem_packet_scope(), &user_name_str); proto_item_append_text(att_tree, ": %s", user_name_str); col_append_fstr( pinfo->cinfo, COL_INFO, " user: %s", user_name_str); if (att_length % 4 != 0) proto_tree_add_uint(att_tree, hf_stun_att_padding, tvb, offset+att_length, 4-(att_length % 4), 4-(att_length % 4)); break; } case MESSAGE_INTEGRITY: if (att_length < 20) break; proto_tree_add_item(att_tree, hf_stun_att_hmac, tvb, offset, att_length, ENC_NA); break; case ERROR_CODE: if (att_length < 2) break; proto_tree_add_item(att_tree, hf_stun_att_reserved, tvb, offset, 2, ENC_NA); if (att_length < 3) break; proto_tree_add_item(att_tree, hf_stun_att_error_class, tvb, offset+2, 1, ENC_BIG_ENDIAN); if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_error_number, tvb, offset+3, 1, ENC_BIG_ENDIAN); { int human_error_num = tvb_get_guint8(tvb, offset+2) * 100 + tvb_get_guint8(tvb, offset+3); const gchar *error_str = val_to_str_ext_const(human_error_num, &error_code_ext, "*Unknown error code*"); proto_item_append_text( att_tree, " %d (%s)", human_error_num, /* human readable error code */ error_str ); col_append_fstr( pinfo->cinfo, COL_INFO, " error-code: %d (%s)", human_error_num, error_str ); } if (att_length < 5) break; { const guint8 *error_reas_str; proto_tree_add_item_ret_string(att_tree, hf_stun_att_error_reason, tvb, offset + 4, att_length - 4, ENC_UTF_8 | ENC_NA, wmem_packet_scope(), &error_reas_str); proto_item_append_text(att_tree, ": %s", error_reas_str); col_append_fstr(pinfo->cinfo, COL_INFO, " %s", error_reas_str); } if (att_length % 4 != 0) proto_tree_add_uint(att_tree, hf_stun_att_padding, tvb, offset+att_length, 4-(att_length % 4), 4-(att_length % 4)); break; case UNKNOWN_ATTRIBUTES: for (i = 0; i < att_length; i += 2) proto_tree_add_item(att_tree, hf_stun_att_unknown, tvb, offset+i, 2, ENC_BIG_ENDIAN); if (att_length % 4 != 0) proto_tree_add_uint(att_tree, hf_stun_att_padding, tvb, offset+att_length, 4-(att_length % 4), 4-(att_length % 4)); break; case REALM: { const guint8 *realm_str; proto_tree_add_item_ret_string(att_tree, hf_stun_att_realm, tvb, offset, att_length, ENC_UTF_8|ENC_NA, wmem_packet_scope(), &realm_str); proto_item_append_text(att_tree, ": %s", realm_str); col_append_fstr(pinfo->cinfo, COL_INFO, " realm: %s", realm_str); if (att_length % 4 != 0) proto_tree_add_uint(att_tree, hf_stun_att_padding, tvb, offset+att_length, 4-(att_length % 4), 4-(att_length % 4)); break; } case NONCE: { const guint8 *nonce_str; proto_tree_add_item_ret_string(att_tree, hf_stun_att_nonce, tvb, offset, att_length, ENC_UTF_8|ENC_NA, wmem_packet_scope(), &nonce_str); proto_item_append_text(att_tree, ": %s", nonce_str); col_append_str(pinfo->cinfo, COL_INFO, " with nonce"); if (att_length % 4 != 0) proto_tree_add_uint(att_tree, hf_stun_att_padding, tvb, offset+att_length, 4-(att_length % 4), 4-(att_length % 4)); break; } case XOR_MAPPED_ADDRESS: case XOR_PEER_ADDRESS: case XOR_RELAYED_ADDRESS: case XOR_RESPONSE_TARGET: case XOR_REFLECTED_FROM: case MS_XOR_MAPPED_ADDRESS: case REMOTE_SITE_ADDR: case REMOTE_RELAY_SITE: case LOCAL_SITE_ADDR: case LOCAL_RELAY_SITE: if (att_length < 1) break; proto_tree_add_item(att_tree, hf_stun_att_reserved, tvb, offset, 1, ENC_NA); if (att_length < 2) break; proto_tree_add_item(att_tree, hf_stun_att_family, tvb, offset+1, 1, ENC_BIG_ENDIAN); if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_xor_port, tvb, offset+2, 2, ENC_NA); /* Show the port 'in the clear' XOR (host order) transid with (host order) xor-port. Add host-order port into tree. */ clear_port = tvb_get_ntohs(tvb, offset+2) ^ (magic_cookie_first_word >> 16); ti = proto_tree_add_uint(att_tree, hf_stun_att_port, tvb, offset+2, 2, clear_port); PROTO_ITEM_SET_GENERATED(ti); if (att_length < 8) break; switch (tvb_get_guint8(tvb, offset+1)) { case 1: proto_tree_add_item(att_tree, hf_stun_att_xor_ipv4, tvb, offset+4, 4, ENC_NA); /* Show the address 'in the clear'. XOR (host order) transid with (host order) xor-address. Add in network order tree. */ clear_ip = tvb_get_ipv4(tvb, offset+4) ^ g_htonl(magic_cookie_first_word); ti = proto_tree_add_ipv4(att_tree, hf_stun_att_ipv4, tvb, offset+4, 4, clear_ip); PROTO_ITEM_SET_GENERATED(ti); { const gchar *ipstr; address addr; guint32 ip; guint16 port; ip = tvb_get_ipv4(tvb, offset+4) ^ g_htonl(magic_cookie_first_word); set_address(&addr, AT_IPv4, 4, &ip); ipstr = address_to_str(wmem_packet_scope(), &addr); port = tvb_get_ntohs(tvb, offset+2) ^ (magic_cookie_first_word >> 16); proto_item_append_text(att_tree, ": %s:%d", ipstr, port); col_append_fstr( pinfo->cinfo, COL_INFO, " %s: %s:%d", attribute_name_str, ipstr, port ); } break; case 2: if (att_length < 20) break; proto_tree_add_item(att_tree, hf_stun_att_xor_ipv6, tvb, offset+4, 16, ENC_NA); { guint32 IPv6[4]; tvb_get_ipv6(tvb, offset+4, (struct e_in6_addr *)IPv6); IPv6[0] = IPv6[0] ^ g_htonl(magic_cookie_first_word); IPv6[1] = IPv6[1] ^ g_htonl(transaction_id[0]); IPv6[2] = IPv6[2] ^ g_htonl(transaction_id[1]); IPv6[3] = IPv6[3] ^ g_htonl(transaction_id[2]); ti = proto_tree_add_ipv6(att_tree, hf_stun_att_ipv6, tvb, offset+4, 16, (const struct e_in6_addr *)IPv6); PROTO_ITEM_SET_GENERATED(ti); } break; } break; case REQUESTED_ADDRESS_TYPE: if (att_length < 1) break; proto_tree_add_item(att_tree, hf_stun_att_family, tvb, offset, 1, ENC_BIG_ENDIAN); if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_reserved, tvb, offset+1, 3, ENC_NA); break; case EVEN_PORT: if (att_length < 1) break; proto_tree_add_item(att_tree, hf_stun_att_reserve_next, tvb, offset, 1, ENC_BIG_ENDIAN); break; case RESERVATION_TOKEN: if (att_length < 8) break; proto_tree_add_item(att_tree, hf_stun_att_token, tvb, offset, 8, ENC_NA); break; case PRIORITY: if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_priority, tvb, offset, 4, ENC_BIG_ENDIAN); break; case PADDING: proto_tree_add_uint(att_tree, hf_stun_att_padding, tvb, offset, att_length, att_length); break; case ICMP: if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_icmp_type, tvb, offset, 1, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_icmp_code, tvb, offset+1, 1, ENC_BIG_ENDIAN); break; case SOFTWARE: proto_tree_add_item(att_tree, hf_stun_att_software, tvb, offset, att_length, ENC_UTF_8|ENC_NA); if (att_length % 4 != 0) proto_tree_add_uint(att_tree, hf_stun_att_padding, tvb, offset+att_length, 4-(att_length % 4), 4-(att_length % 4)); break; case CACHE_TIMEOUT: if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_cache_timeout, tvb, offset, 4, ENC_BIG_ENDIAN); break; case FINGERPRINT: if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_crc32, tvb, offset, att_length, ENC_BIG_ENDIAN); break; case ICE_CONTROLLED: case ICE_CONTROLLING: if (att_length < 8) break; proto_tree_add_item(att_tree, hf_stun_att_tie_breaker, tvb, offset, 8, ENC_NA); break; case DATA: if (att_length > 0) { tvbuff_t *next_tvb; proto_tree_add_item(att_tree, hf_stun_att_value, tvb, offset, att_length, ENC_NA); if (att_length % 4 != 0) { guint pad; pad = 4-(att_length % 4); proto_tree_add_uint(att_tree, hf_stun_att_padding, tvb, offset+att_length, pad, pad); } next_tvb = tvb_new_subset_length(tvb, offset, att_length); if (!dissector_try_heuristic(heur_subdissector_list, next_tvb, pinfo, att_tree, &hdtbl_entry, NULL)) { call_dissector_only(data_handle, next_tvb, pinfo, att_tree, NULL); } } break; case REQUESTED_TRANSPORT: if (att_length < 1) break; proto_tree_add_item(att_tree, hf_stun_att_transp, tvb, offset, 1, ENC_BIG_ENDIAN); if (att_length < 4) break; { guint8 protoCode = tvb_get_guint8(tvb, offset); const gchar *protoCode_str = val_to_str(protoCode, transportnames, "Unknown (0x%8x)"); proto_item_append_text(att_tree, ": %s", protoCode_str); col_append_fstr( pinfo->cinfo, COL_INFO, " %s", protoCode_str ); } proto_tree_add_item(att_tree, hf_stun_att_reserved, tvb, offset+1, 3, ENC_NA); break; case CHANNEL_NUMBER: if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_channelnum, tvb, offset, 2, ENC_BIG_ENDIAN); { guint16 chan = tvb_get_ntohs(tvb, offset); proto_item_append_text(att_tree, ": 0x%x", chan); col_append_fstr( pinfo->cinfo, COL_INFO, " ChannelNumber=0x%x", chan ); } proto_tree_add_item(att_tree, hf_stun_att_reserved, tvb, offset+2, 2, ENC_NA); break; case MAGIC_COOKIE: if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_magic_cookie, tvb, offset, 4, ENC_BIG_ENDIAN); break; case BANDWIDTH: if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_bandwidth, tvb, offset, 4, ENC_BIG_ENDIAN); proto_item_append_text(att_tree, " %d", tvb_get_ntohl(tvb, offset)); col_append_fstr( pinfo->cinfo, COL_INFO, " bandwidth: %d", tvb_get_ntohl(tvb, offset) ); break; case LIFETIME: if (att_length < 4) break; proto_tree_add_item(att_tree, hf_stun_att_lifetime, tvb, offset, 4, ENC_BIG_ENDIAN); proto_item_append_text(att_tree, " %d", tvb_get_ntohl(tvb, offset)); col_append_fstr( pinfo->cinfo, COL_INFO, " lifetime: %d", tvb_get_ntohl(tvb, offset) ); break; case MS_VERSION: case MS_IMPLEMENTATION_VER: proto_tree_add_item(att_tree, hf_stun_att_ms_version, tvb, offset, 4, ENC_BIG_ENDIAN); proto_item_append_text(att_tree, ": %s", val_to_str(tvb_get_ntohl(tvb, offset), ms_version_vals, "Unknown (0x%u)")); break; case MS_SEQUENCE_NUMBER: proto_tree_add_item(att_tree, hf_stun_att_ms_connection_id, tvb, offset, 20, ENC_NA); proto_tree_add_item(att_tree, hf_stun_att_ms_sequence_number, tvb, offset+20, 4, ENC_BIG_ENDIAN); break; case MS_SERVICE_QUALITY: proto_tree_add_item(att_tree, hf_stun_att_ms_stream_type, tvb, offset, 2, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_ms_service_quality, tvb, offset+2, 2, ENC_BIG_ENDIAN); break; case BANDWIDTH_ACM: proto_tree_add_item(att_tree, hf_stun_att_reserved, tvb, offset, 2, ENC_NA); proto_tree_add_item(att_tree, hf_stun_att_bandwidth_acm_type, tvb, offset+2, 2, ENC_BIG_ENDIAN); break; case BANDWIDTH_RSV_ID: proto_tree_add_item(att_tree, hf_stun_att_bandwidth_rsv_id, tvb, offset, 16, ENC_NA); break; case BANDWIDTH_RSV_AMOUNT: proto_tree_add_item(att_tree, hf_stun_att_bandwidth_rsv_amount_masb, tvb, offset, 4, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_bandwidth_rsv_amount_misb, tvb, offset+4, 4, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_bandwidth_rsv_amount_marb, tvb, offset+8, 4, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_bandwidth_rsv_amount_mirb, tvb, offset+12, 4, ENC_BIG_ENDIAN); break; case REMOTE_SITE_ADDR_RP: case LOCAL_SITE_ADDR_RP: proto_tree_add_item(att_tree, hf_stun_att_address_rp_a, tvb, offset, 4, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_address_rp_b, tvb, offset, 4, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_address_rp_rsv1, tvb, offset, 4, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_address_rp_masb, tvb, offset+4, 4, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_address_rp_marb, tvb, offset+8, 4, ENC_BIG_ENDIAN); break; case REMOTE_RELAY_SITE_RP: case LOCAL_RELAY_SITE_RP: proto_tree_add_item(att_tree, hf_stun_att_address_rp_a, tvb, offset, 4, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_address_rp_rsv2, tvb, offset, 4, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_address_rp_masb, tvb, offset+4, 4, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_address_rp_marb, tvb, offset+8, 4, ENC_BIG_ENDIAN); break; case SIP_DIALOG_ID: proto_tree_add_item(att_tree, hf_stun_att_sip_dialog_id, tvb, offset, att_length, ENC_NA); break; case SIP_CALL_ID: proto_tree_add_item(att_tree, hf_stun_att_sip_call_id, tvb, offset, att_length, ENC_NA); break; case LOCATION_PROFILE: proto_tree_add_item(att_tree, hf_stun_att_lp_peer_location, tvb, offset, 1, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_lp_self_location, tvb, offset+1, 1, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_lp_federation, tvb, offset+2, 1, ENC_BIG_ENDIAN); proto_tree_add_item(att_tree, hf_stun_att_reserved, tvb, offset+3, 1, ENC_NA); break; case MS_CANDIDATE_IDENTIFIER: proto_tree_add_item(att_tree, hf_stun_att_ms_foundation, tvb, offset, 4, ENC_ASCII|ENC_NA); break; default: if (att_length > 0) proto_tree_add_item(att_tree, hf_stun_att_value, tvb, offset, att_length, ENC_NA); if (att_length % 4 != 0) proto_tree_add_uint(att_tree, hf_stun_att_padding, tvb, offset+att_length, 4-(att_length % 4), 4-(att_length % 4)); break; } offset += (att_length+3) & ~0x3; } } if (heur_check && is_turn && conversation) { /* * When in heuristic dissector mode, if this is a TURN message, set * the 5-tuple conversation to always decode as non-heuristic. The * odds of incorrectly identifying a random packet as a TURN message * (other than ChannelData) is incredibly small. A ChannelData message * won't be matched when in heuristic mode, so heur_check can't be true * in that case and get to this part of the code. */ if (pinfo->ptype == PT_TCP) { conversation_set_dissector(conversation, stun_tcp_handle); } else if (pinfo->ptype == PT_UDP) { conversation_set_dissector(conversation, stun_udp_handle); } } if (!PINFO_FD_VISITED(pinfo) && is_turn && (pinfo->ptype == PT_TCP) && (msg_type_method == CONNECTION_BIND) && (msg_type_class == RESPONSE)) { /* RFC 6062: after the ConnectionBind exchange, the connection is no longer framed as TURN; instead, it is an unframed pass-through. Starting from next frame set conversation dissector to data */ conversation_set_dissector_from_frame_number(conversation, pinfo->num+1, data_handle); } return reported_length; } static int dissect_stun_udp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) { return dissect_stun_message(tvb, pinfo, tree, FALSE, TRUE); } static int dissect_stun_tcp_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) { return dissect_stun_message(tvb, pinfo, tree, FALSE, FALSE); } static int dissect_stun_tcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data) { tcp_dissect_pdus(tvb, pinfo, tree, TRUE, MIN_HDR_LEN, get_stun_message_len, dissect_stun_tcp_pdu, data); return tvb_reported_length(tvb); } static gboolean dissect_stun_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) { if (dissect_stun_message(tvb, pinfo, tree, TRUE, TRUE) == 0) { /* * It wasn't a valid STUN message, and wasn't * dissected as such. */ return FALSE; } return TRUE; } void proto_register_stun(void) { static hf_register_info hf[] = { { &hf_stun_channel, { "Channel Number", "stun.channel", FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL } }, /* ////////////////////////////////////// */ { &hf_stun_tcp_frame_length, { "TCP Frame Length", "stun.tcp_frame_length", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_stun_type, { "Message Type", "stun.type", FT_UINT16, BASE_HEX, NULL,0, NULL, HFILL } }, { &hf_stun_type_class, { "Message Class", "stun.type.class", FT_UINT16, BASE_HEX, NULL, 0x0110, NULL, HFILL } }, { &hf_stun_type_method, { "Message Method", "stun.type.method", FT_UINT16, BASE_HEX, NULL, 0x3EEF, NULL, HFILL } }, { &hf_stun_type_method_assignment, { "Message Method Assignment", "stun.type.method-assignment", FT_UINT16, BASE_HEX, VALS(assignments), 0x2000, NULL, HFILL } }, { &hf_stun_length, { "Message Length", "stun.length", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_stun_cookie, { "Message Cookie", "stun.cookie", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_id, { "Message Transaction ID", "stun.id", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_attributes, { "Attributes", "stun.attributes", FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_attr, { "Attribute Type", "stun.attribute", FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL } }, { &hf_stun_response_in, { "Response In", "stun.response-in", FT_FRAMENUM, BASE_NONE, NULL, 0x0, "The response to this STUN query is in this frame", HFILL } }, { &hf_stun_response_to, { "Request In", "stun.response-to", FT_FRAMENUM, BASE_NONE, NULL, 0x0, "This is a response to the STUN Request in this frame", HFILL } }, { &hf_stun_time, { "Time", "stun.time", FT_RELATIVE_TIME, BASE_NONE, NULL, 0x0, "The time between the Request and the Response", HFILL } }, { &hf_stun_duplicate, { "Duplicated original message in", "stun.reqduplicate", FT_FRAMENUM, BASE_NONE, NULL, 0x0, "This is a duplicate of STUN message in this frame", HFILL } }, /* ////////////////////////////////////// */ { &hf_stun_att_type, { "Attribute Type", "stun.att.type", FT_UINT16, BASE_HEX | BASE_EXT_STRING, &attributes_ext, 0x0, NULL, HFILL } }, { &hf_stun_att_type_comprehension, { "Attribute Type Comprehension", "stun.att.type.comprehension", FT_UINT16, BASE_HEX, VALS(comprehensions), 0x8000, NULL, HFILL } }, { &hf_stun_att_type_assignment, { "Attribute Type Assignment", "stun.att.type.assignment", FT_UINT16, BASE_HEX, VALS(assignments), 0x4000, NULL, HFILL } }, { &hf_stun_att_length, { "Attribute Length", "stun.att.length", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_family, { "Protocol Family", "stun.att.family", FT_UINT8, BASE_HEX, VALS(attributes_family), 0x0, NULL, HFILL } }, { &hf_stun_att_ipv4, { "IP", "stun.att.ipv4", FT_IPv4, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_ipv6, { "IP", "stun.att.ipv6", FT_IPv6, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_port, { "Port", "stun.att.port", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_username, { "Username", "stun.att.username", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_password, { "Password", "stun.att.password", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_padding, { "Padding", "stun.att.padding", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_hmac, { "HMAC-SHA1", "stun.att.hmac", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_crc32, { "CRC-32", "stun.att.crc32", FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_error_class, { "Error Class","stun.att.error.class", FT_UINT8, BASE_DEC, NULL, 0x07, NULL, HFILL} }, { &hf_stun_att_error_number, { "Error Code","stun.att.error", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_error_reason, { "Error Reason Phrase","stun.att.error.reason", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_realm, { "Realm", "stun.att.realm", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_nonce, { "Nonce", "stun.att.nonce", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_unknown, { "Unknown Attribute","stun.att.unknown", FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_xor_ipv4, { "IP (XOR-d)", "stun.att.ipv4-xord", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_xor_ipv6, { "IP (XOR-d)", "stun.att.ipv6-xord", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_xor_port, { "Port (XOR-d)", "stun.att.port-xord", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_icmp_type, { "ICMP type", "stun.att.icmp.type", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_icmp_code, { "ICMP code", "stun.att.icmp.code", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_software, { "Software","stun.att.software", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_priority, { "Priority", "stun.att.priority", FT_UINT32, BASE_DEC, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_tie_breaker, { "Tie breaker", "stun.att.tie-breaker", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_lifetime, { "Lifetime", "stun.att.lifetime", FT_UINT32, BASE_DEC, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_change_ip, { "Change IP","stun.att.change-ip", FT_BOOLEAN, 16, TFS(&tfs_set_notset), 0x0004, NULL, HFILL} }, { &hf_stun_att_change_port, { "Change Port","stun.att.change-port", FT_BOOLEAN, 16, TFS(&tfs_set_notset), 0x0002, NULL, HFILL} }, { &hf_stun_att_reserve_next, { "Reserve next","stun.att.even-port.reserve-next", FT_UINT8, BASE_DEC, VALS(attributes_reserve_next), 0x80, NULL, HFILL} }, { &hf_stun_att_cache_timeout, { "Cache timeout", "stun.att.cache-timeout", FT_UINT32, BASE_DEC, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_token, { "Token", "stun.att.token", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_value, { "Value", "stun.value", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_reserved, { "Reserved", "stun.att.reserved", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_transp, { "Transport", "stun.att.transp", FT_UINT8, BASE_HEX, VALS(transportnames), 0x0, NULL, HFILL } }, { &hf_stun_att_channelnum, { "Channel-Number", "stun.att.channelnum", FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_magic_cookie, { "Magic Cookie", "stun.att.magic_cookie", FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_bandwidth, { "Bandwidth", "stun.port.bandwidth", FT_UINT32, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_stun_att_ms_version, { "MS Version", "stun.att.ms.version", FT_UINT32, BASE_DEC, VALS(ms_version_vals), 0x0, NULL, HFILL} }, { &hf_stun_att_ms_connection_id, { "Connection ID", "stun.att.ms.connection_id", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_ms_sequence_number, { "Sequence Number", "stun.att.ms.sequence_number", FT_UINT32, BASE_DEC, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_ms_stream_type, { "Stream Type", "stun.att.ms.stream_type", FT_UINT16, BASE_DEC, VALS(ms_stream_type_vals), 0x0, NULL, HFILL} }, { &hf_stun_att_ms_service_quality, { "Service Quality", "stun.att.ms.service_quality", FT_UINT16, BASE_DEC, VALS(ms_service_quality_vals), 0x0, NULL, HFILL} }, { &hf_stun_att_ms_foundation, { "Foundation", "stun.att.ms.foundation", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_bandwidth_acm_type, { "Message Type", "stun.att.bandwidth_acm.type", FT_UINT16, BASE_DEC, VALS(bandwidth_acm_type_vals), 0x0, NULL, HFILL} }, { &hf_stun_att_bandwidth_rsv_id, { "Reservation ID", "stun.att.bandwidth_rsv_id", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_bandwidth_rsv_amount_misb, { "Minimum Send Bandwidth", "stun.att.bandwidth_rsv_amount.misb", FT_UINT32, BASE_DEC, NULL, 0x0, "In kilobits per second", HFILL} }, { &hf_stun_att_bandwidth_rsv_amount_masb, { "Maximum Send Bandwidth", "stun.att.bandwidth_rsv_amount.masb", FT_UINT32, BASE_DEC, NULL, 0x0, "In kilobits per second", HFILL} }, { &hf_stun_att_bandwidth_rsv_amount_mirb, { "Minimum Receive Bandwidth", "stun.att.bandwidth_rsv_amount.mirb", FT_UINT32, BASE_DEC, NULL, 0x0, "In kilobits per second", HFILL} }, { &hf_stun_att_bandwidth_rsv_amount_marb, { "Maximum Receive Bandwidth", "stun.att.bandwidth_rsv_amount.marb", FT_UINT32, BASE_DEC, NULL, 0x0, "In kilobits per second", HFILL} }, { &hf_stun_att_address_rp_a, { "Valid", "stun.att.address_rp.valid", FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x80000000, NULL, HFILL} }, { &hf_stun_att_address_rp_b, { "PSTN", "stun.att.address_rp.valid", FT_BOOLEAN, 32, TFS(&tfs_yes_no), 0x40000000, NULL, HFILL} }, { &hf_stun_att_address_rp_rsv1, { "Reserved", "stun.att.address_rp.reserved", FT_UINT32, BASE_HEX, NULL, 0x3FFFFFFF, NULL, HFILL} }, { &hf_stun_att_address_rp_rsv2, { "Reserved", "stun.att.address_rp.reserved", FT_UINT32, BASE_HEX, NULL, 0x7FFFFFFF, NULL, HFILL} }, { &hf_stun_att_address_rp_masb, { "Maximum Send Bandwidth", "stun.att.adress_rp.masb", FT_UINT32, BASE_DEC, NULL, 0x0, "In kilobits per second", HFILL} }, { &hf_stun_att_address_rp_marb, { "Maximum Receive Bandwidth", "stun.att.adress_rp.marb", FT_UINT32, BASE_DEC, NULL, 0x0, "In kilobits per second", HFILL} }, { &hf_stun_att_sip_dialog_id, { "SIP Dialog ID", "stun.att.sip_dialog_id", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_sip_call_id, { "SIP Call ID", "stun.att.sip_call_id", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL} }, { &hf_stun_att_lp_peer_location, { "Peer Location", "stun.att.lp.peer_location", FT_UINT8, BASE_DEC, VALS(location_vals), 0x0, NULL, HFILL} }, { &hf_stun_att_lp_self_location, { "Self Location", "stun.att.lp.seft_location", FT_UINT8, BASE_DEC, VALS(location_vals), 0x0, NULL, HFILL} }, { &hf_stun_att_lp_federation, { "Federation", "stun.att.lp.federation", FT_UINT8, BASE_DEC, VALS(federation_vals), 0x0, NULL, HFILL} }, }; /* Setup protocol subtree array */ static gint *ett[] = { &ett_stun, &ett_stun_type, &ett_stun_att_all, &ett_stun_att, &ett_stun_att_type, }; /* Register the protocol name and description */ proto_stun = proto_register_protocol("Session Traversal Utilities for NAT", "STUN", "stun"); /* Required function calls to register the header fields and subtrees used */ proto_register_field_array(proto_stun, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); /* heuristic subdissectors (used for the DATA field) */ heur_subdissector_list = register_heur_dissector_list("stun", proto_stun); register_dissector("stun-udp", dissect_stun_udp, proto_stun); register_dissector("stun-heur", dissect_stun_heur, proto_stun); } void proto_reg_handoff_stun(void) { stun_tcp_handle = create_dissector_handle(dissect_stun_tcp, proto_stun); stun_udp_handle = create_dissector_handle(dissect_stun_udp, proto_stun); dissector_add_uint_with_preference("tcp.port", TCP_PORT_STUN, stun_tcp_handle); dissector_add_uint_with_preference("udp.port", UDP_PORT_STUN, stun_udp_handle); heur_dissector_add("udp", dissect_stun_heur, "STUN over UDP", "stun_udp", proto_stun, HEURISTIC_ENABLE); data_handle = find_dissector("data"); } /* * Editor modelines * * Local Variables: * c-basic-offset: 4 * tab-width: 8 * indent-tabs-mode: nil * End: * * ex: set shiftwidth=4 tabstop=8 expandtab: * :indentSize=4:tabSize=8:noTabs=true: */