/* packet-netbios.c * Routines for NetBIOS protocol packet disassembly * Jeff Foster * Copyright 1999 Jeffrey C. Foster * * derived from the packet-nbns.c * * $Id: packet-netbios.c,v 1.57 2003/04/20 11:36:14 guy Exp $ * * Ethereal - 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #include #include #include "llcsaps.h" #include "reassemble.h" #include "prefs.h" #include "packet-netbios.h" /* Netbios command numbers */ #define NB_ADD_GROUP 0x00 #define NB_ADD_NAME 0x01 #define NB_NAME_IN_CONFLICT 0x02 #define NB_STATUS_QUERY 0x03 #define NB_TERMINATE_TRACE_R 0x07 #define NB_DATAGRAM 0x08 #define NB_DATAGRAM_BCAST 0x09 #define NB_NAME_QUERY 0x0a #define NB_ADD_NAME_RESP 0x0d #define NB_NAME_RESP 0x0e #define NB_STATUS_RESP 0x0f #define NB_TERMINATE_TRACE_LR 0x13 #define NB_DATA_ACK 0x14 #define NB_DATA_FIRST_MIDDLE 0x15 #define NB_DATA_ONLY_LAST 0x16 #define NB_SESSION_CONFIRM 0x17 #define NB_SESSION_END 0x18 #define NB_SESSION_INIT 0x19 #define NB_NO_RECEIVE 0x1a #define NB_RECEIVE_OUTSTANDING 0x1b #define NB_RECEIVE_CONTINUE 0x1c #define NB_KEEP_ALIVE 0x1f /* Offsets of fields in the NetBIOS header. */ #define NB_LENGTH 0 #define NB_DELIMITER 2 #define NB_COMMAND 4 #define NB_FLAGS 5 #define NB_DATA1 5 #define NB_RESYNC 6 #define NB_DATA2 6 #define NB_CALL_NAME_TYPE 7 #define NB_XMIT_CORL 8 #define NB_RESP_CORL 10 #define NB_RMT_SES 12 #define NB_LOCAL_SES 13 #define NB_RECVER_NAME 12 #define NB_SENDER_NAME 28 static int proto_netbios = -1; static int hf_netb_cmd = -1; static int hf_netb_hdr_len = -1; static int hf_netb_xmit_corrl = -1; static int hf_netb_resp_corrl = -1; static int hf_netb_call_name_type = -1; static int hf_netb_ack = -1; static int hf_netb_ack_with_data = -1; static int hf_netb_ack_expected = -1; static int hf_netb_recv_cont_req = -1; static int hf_netb_send_no_ack = -1; static int hf_netb_version = -1; static int hf_netb_largest_frame = -1; static int hf_netb_nb_name = -1; static int hf_netb_nb_name_type = -1; static int hf_netb_status_buffer_len = -1; static int hf_netb_status = -1; static int hf_netb_name_type = -1; static int hf_netb_max_data_recv_size = -1; static int hf_netb_termination_indicator = -1; static int hf_netb_num_data_bytes_accepted = -1; static int hf_netb_local_ses_no = -1; static int hf_netb_remote_ses_no = -1; static int hf_netb_data1 = -1; static int hf_netb_data2 = -1; static int hf_netb_fragments = -1; static int hf_netb_fragment = -1; static int hf_netb_fragment_overlap = -1; static int hf_netb_fragment_overlap_conflict = -1; static int hf_netb_fragment_multiple_tails = -1; static int hf_netb_fragment_too_long_fragment = -1; static int hf_netb_fragment_error = -1; static gint ett_netb = -1; static gint ett_netb_name = -1; static gint ett_netb_flags = -1; static gint ett_netb_status = -1; static gint ett_netb_fragments = -1; static gint ett_netb_fragment = -1; static const fragment_items netbios_frag_items = { &ett_netb_fragment, &ett_netb_fragments, &hf_netb_fragments, &hf_netb_fragment, &hf_netb_fragment_overlap, &hf_netb_fragment_overlap_conflict, &hf_netb_fragment_multiple_tails, &hf_netb_fragment_too_long_fragment, &hf_netb_fragment_error, NULL, "fragments" }; static dissector_handle_t data_handle; /* The strings for the station type, used by get_netbios_name function; many of them came from the file "NetBIOS.txt" in the Zip archive at http://www.net3group.com/ftp/browser.zip */ static const value_string nb_name_type_vals[] = { {0x00, "Workstation/Redirector"}, {0x01, "Browser"}, {0x02, "Workstation/Redirector"}, /* not sure what 0x02 is, I'm seeing alot of them however */ /* i'm seeing them with workstation/redirection host announcements */ {0x03, "Messenger service/Main name"}, {0x05, "Forwarded name"}, {0x06, "RAS Server service"}, {0x1b, "Domain Master Browser"}, {0x1c, "Domain Controllers"}, {0x1d, "Local Master Browser"}, {0x1e, "Browser Election Service"}, {0x1f, "Net DDE Service"}, {0x20, "Server service"}, {0x21, "RAS client service"}, {0x22, "Exchange Interchange (MSMail Connector)"}, {0x23, "Exchange Store"}, {0x24, "Exchange Directory"}, {0x2b, "Lotus Notes Server service"}, {0x30, "Modem sharing server service"}, {0x31, "Modem sharing client service"}, {0x43, "SMS Clients Remote Control"}, {0x44, "SMS Administrators Remote Control Tool"}, {0x45, "SMS Clients Remote Chat"}, {0x46, "SMS Clients Remote Transfer"}, {0x4c, "DEC Pathworks TCP/IP Service on Windows NT"}, {0x52, "DEC Pathworks TCP/IP Service on Windows NT"}, {0x6a, "Microsoft Exchange IMC"}, {0x87, "Microsoft Exchange MTA"}, {0xbe, "Network Monitor Agent"}, {0xbf, "Network Monitor Analyzer"}, {0x00, NULL} }; /* Tables for reassembly of fragments. */ static GHashTable *netbios_fragment_table = NULL; static GHashTable *netbios_reassembled_table = NULL; /* defragmentation of NetBIOS Frame */ static gboolean netbios_defragment = TRUE; /* See http://www.s390.ibm.com/bookmgr-cgi/bookmgr.cmd/BOOKS/BK8P7001/CCONTENTS and http://ourworld.compuserve.com/homepages/TimothyDEvans/contents.htm for information about the NetBIOS Frame Protocol (which is what this module dissects). */ /* the strings for the command types */ static const value_string cmd_vals[] = { { NB_ADD_GROUP, "Add Group Name Query" }, { NB_ADD_NAME, "Add Name Query" }, { NB_NAME_IN_CONFLICT, "Name In Conflict" }, { NB_STATUS_QUERY, "Status Query" }, { NB_TERMINATE_TRACE_R, "Terminate Trace" }, { NB_DATAGRAM, "Datagram" }, { NB_DATAGRAM_BCAST, "Broadcast Datagram" }, { NB_NAME_QUERY, "Name Query" }, { NB_ADD_NAME_RESP, "Add Name Response" }, { NB_NAME_RESP, "Name Recognized" }, { NB_STATUS_RESP, "Status Response" }, { NB_TERMINATE_TRACE_LR, "Terminate Trace" }, { NB_DATA_ACK, "Data Ack" }, { NB_DATA_FIRST_MIDDLE, "Data First Middle" }, { NB_DATA_ONLY_LAST, "Data Only Last" }, { NB_SESSION_CONFIRM, "Session Confirm" }, { NB_SESSION_END, "Session End" }, { NB_SESSION_INIT, "Session Initialize" }, { NB_NO_RECEIVE, "No Receive" }, { NB_RECEIVE_OUTSTANDING, "Receive Outstanding" }, { NB_RECEIVE_CONTINUE, "Receive Continue" }, { NB_KEEP_ALIVE, "Session Alive" }, { 0, NULL } }; static const value_string name_types[] = { { 0, "Unique name" }, { 1, "Group name" }, { 0, NULL } }; static const true_false_string flags_set = { "Set", "Not set" }; static const true_false_string flags_allowed = { "Allowed", "Not allowed" }; static const true_false_string flags_yes_no = { "Yes", "No" }; static const true_false_string netb_version_str = { "2.00 or higher", "1.xx" }; static const value_string termination_indicator_vals[] = { { 0x0000, "Normal session end" }, { 0x0001, "Abnormal session end" }, { 0, NULL } }; static const value_string status_vals[] = { { 0, "Add name not in process" }, { 1, "Add name in process" }, { 0, NULL } }; static const value_string max_frame_size_vals[] = { { 0, "516" }, { 1, "1500" }, { 2, "2052" }, { 3, "4472" }, { 4, "8144" }, { 5, "11407" }, { 6, "17800" }, /* 17800 in TR spec, 17749 in NBF spec */ { 7, "65535" }, { 0, NULL } }; void capture_netbios(packet_counts *ld) { ld->netbios++; } int process_netbios_name(const guchar *name_ptr, char *name_ret) { int i; int name_type = *(name_ptr + NETBIOS_NAME_LEN - 1); guchar name_char; static const char hex_digits[16] = "0123456789abcdef"; for (i = 0; i < NETBIOS_NAME_LEN - 1; i++) { name_char = *name_ptr++; if (name_char >= ' ' && name_char <= '~') *name_ret++ = name_char; else { /* It's not printable; show it as , where XX is the value in hex. */ *name_ret++ = '<'; *name_ret++ = hex_digits[(name_char >> 4)]; *name_ret++ = hex_digits[(name_char & 0x0F)]; *name_ret++ = '>'; } } *name_ret = '\0'; /* Remove trailing space characters from name. */ name_ret--; for (i = 0; i < NETBIOS_NAME_LEN - 1; i++) { if (*name_ret != ' ') { *(name_ret + 1) = 0; break; } name_ret--; } return name_type; } int get_netbios_name( tvbuff_t *tvb, int offset, char *name_ret) {/* Extract the name string and name type. Return the name string in */ /* name_ret and return the name_type. */ return process_netbios_name( tvb_get_ptr( tvb, offset, NETBIOS_NAME_LEN ), name_ret); } /* * Get a string describing the type of a NetBIOS name. */ char * netbios_name_type_descr(int name_type) { return val_to_str(name_type, nb_name_type_vals, "Unknown"); } void netbios_add_name(char* label, tvbuff_t *tvb, int offset, proto_tree *tree) {/* add a name field display tree. Display the name and station type in sub-tree */ proto_tree *field_tree; proto_item *tf; char name_str[(NETBIOS_NAME_LEN - 1)*4 + 1]; int name_type; char *name_type_str; /* decode the name field */ name_type = get_netbios_name( tvb, offset, name_str); name_type_str = netbios_name_type_descr(name_type); tf = proto_tree_add_text( tree, tvb, offset, NETBIOS_NAME_LEN, "%s: %s<%02x> (%s)", label, name_str, name_type, name_type_str); field_tree = proto_item_add_subtree( tf, ett_netb_name); proto_tree_add_string_format( field_tree, hf_netb_nb_name, tvb, offset, 15, name_str, "%s", name_str); proto_tree_add_uint_format( field_tree, hf_netb_nb_name_type, tvb, offset + 15, 1, name_type, "0x%02x (%s)", name_type, name_type_str); } static void netbios_data_first_middle_flags( tvbuff_t *tvb, proto_tree *tree, int offset) { proto_tree *field_tree; proto_item *tf; guint flags = tvb_get_guint8( tvb, offset); /* decode the flag field for Data First Middle packet*/ tf = proto_tree_add_text(tree, tvb, offset, 1, "Flags: 0x%02x", flags); field_tree = proto_item_add_subtree(tf, ett_netb_flags); proto_tree_add_boolean( field_tree, hf_netb_ack, tvb, offset, 1, flags); proto_tree_add_boolean( field_tree, hf_netb_ack_expected, tvb, offset, 1, flags); proto_tree_add_boolean( field_tree, hf_netb_recv_cont_req, tvb, offset, 1, flags); } static void netbios_data_only_flags( tvbuff_t *tvb, proto_tree *tree, int offset) { proto_tree *field_tree; proto_item *tf; guint flags = tvb_get_guint8( tvb, offset); /* decode the flag field for Data Only Last packet*/ tf = proto_tree_add_text(tree, tvb, offset, 1, "Flags: 0x%02x", flags); field_tree = proto_item_add_subtree(tf, ett_netb_flags); proto_tree_add_boolean( field_tree, hf_netb_ack, tvb, offset, 1, flags); proto_tree_add_boolean( field_tree, hf_netb_ack_with_data, tvb, offset, 1, flags); proto_tree_add_boolean( field_tree, hf_netb_ack_expected, tvb, offset, 1, flags); } static void netbios_add_ses_confirm_flags( tvbuff_t *tvb, proto_tree *tree, int offset) { proto_tree *field_tree; proto_item *tf; guint flags = tvb_get_guint8( tvb, offset); /* decode the flag field for Session Confirm packet */ tf = proto_tree_add_text(tree, tvb, offset, 1, "Flags: 0x%02x", flags); field_tree = proto_item_add_subtree( tf, ett_netb_flags); proto_tree_add_boolean( field_tree, hf_netb_send_no_ack, tvb, offset, 1, flags); proto_tree_add_boolean( field_tree, hf_netb_version, tvb, offset, 1, flags); } static void netbios_add_session_init_flags( tvbuff_t *tvb, proto_tree *tree, int offset) { proto_tree *field_tree; proto_item *tf; guint flags = tvb_get_guint8( tvb, offset); /* decode the flag field for Session Init packet */ tf = proto_tree_add_text(tree, tvb, offset, 1, "Flags: 0x%02x", flags); field_tree = proto_item_add_subtree(tf, ett_netb_flags); proto_tree_add_boolean( field_tree, hf_netb_send_no_ack, tvb, offset, 1, flags); proto_tree_add_uint( field_tree, hf_netb_largest_frame, tvb, offset, 1, flags); proto_tree_add_boolean( field_tree, hf_netb_version, tvb, offset, 1, flags); } static void netbios_no_receive_flags( tvbuff_t *tvb, proto_tree *tree, int offset) { proto_tree *field_tree; proto_item *tf; guint flags = tvb_get_guint8( tvb, offset); /* decode the flag field for No Receive packet*/ tf = proto_tree_add_text(tree, tvb, offset, 1, "Flags: 0x%02x", flags); if (flags & 0x02) { field_tree = proto_item_add_subtree(tf, ett_netb_flags); proto_tree_add_text(field_tree, tvb, offset, 1, "%s", decode_boolean_bitfield(flags, 0x02, 8, "SEND.NO.ACK data not received", NULL)); } } /************************************************************************/ /* */ /* The routines to display the netbios field values in the tree */ /* */ /************************************************************************/ static void nb_xmit_corrl( tvbuff_t *tvb, int offset, proto_tree *tree) {/* display the transmit correlator */ proto_tree_add_item( tree, hf_netb_xmit_corrl, tvb, offset + NB_XMIT_CORL, 2, TRUE); } static void nb_resp_corrl( tvbuff_t *tvb, int offset, proto_tree *tree) {/* display the response correlator */ proto_tree_add_item( tree, hf_netb_resp_corrl, tvb, offset + NB_RESP_CORL, 2, TRUE); } static void nb_call_name_type( tvbuff_t *tvb, int offset, proto_tree *tree) {/* display the call name type */ proto_tree_add_item( tree, hf_netb_call_name_type, tvb, offset + NB_CALL_NAME_TYPE, 1, TRUE); } static guint8 nb_local_session( tvbuff_t *tvb, int offset, proto_tree *tree) {/* add the local session to tree, and return its value */ guint8 local_session = tvb_get_guint8( tvb, offset + NB_LOCAL_SES); proto_tree_add_uint( tree, hf_netb_local_ses_no, tvb, offset + NB_LOCAL_SES, 1, local_session); return local_session; } static guint8 nb_remote_session( tvbuff_t *tvb, int offset, proto_tree *tree) {/* add the remote session to tree, and return its value */ guint8 remote_session = tvb_get_guint8( tvb, offset + NB_RMT_SES); proto_tree_add_uint( tree, hf_netb_remote_ses_no, tvb, offset + NB_RMT_SES, 1, remote_session); return remote_session; } static void nb_data1(int hf, tvbuff_t *tvb, int offset, proto_tree *tree) {/* add the DATA1 to tree with specified hf_ value */ proto_tree_add_item( tree, hf, tvb, offset + NB_DATA1, 1, TRUE); } static void nb_data2(int hf, tvbuff_t *tvb, int offset, proto_tree *tree) {/* add the DATA2 to tree with specified hf_ value */ proto_tree_add_item( tree, hf, tvb, offset + NB_DATA2, 2, TRUE); } static void nb_resync_indicator( tvbuff_t *tvb, int offset, proto_tree *tree, char *cmd_str) { guint16 resync_indicator = tvb_get_letohs( tvb, offset + NB_DATA2); switch (resync_indicator) { case 0x0000: proto_tree_add_text(tree, tvb, offset + NB_DATA2, 2, "Re-sync indicator: No re-sync"); break; case 0x0001: proto_tree_add_text(tree, tvb, offset + NB_DATA2, 2, "Re-sync indicator: First '%s' following 'Receive Outstanding'", cmd_str); break; default: proto_tree_add_text(tree, tvb, offset + NB_DATA2, 2, "Re-sync indicator: 0x%04x", resync_indicator); break; } } /************************************************************************/ /* */ /* The routines called by the top level to handle individual commands */ /* */ /************************************************************************/ static guint32 dissect_netb_unknown( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle any unknown commands, do nothing */ proto_tree_add_text(tree, tvb, offset + NB_COMMAND + 1, -1, "Unknown NetBIOS command data"); return 0; } static guint32 dissect_netb_add_group_name( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the ADD GROUP NAME QUERY command */ nb_resp_corrl( tvb, offset, tree); netbios_add_name("Group name to add", tvb, offset + NB_SENDER_NAME, tree); return 0; } static guint32 dissect_netb_add_name( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the ADD NAME QUERY command */ nb_resp_corrl( tvb, offset, tree); netbios_add_name("Name to add", tvb, offset + NB_SENDER_NAME, tree); return 0; } static guint32 dissect_netb_name_in_conflict( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the NAME IN CONFLICT command */ netbios_add_name("Name In Conflict", tvb, offset + NB_RECVER_NAME, tree); netbios_add_name("Sender's Name", tvb, offset + NB_SENDER_NAME, tree); return 0; } static guint32 dissect_netb_status_query( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the STATUS QUERY command */ guint8 status_request = tvb_get_guint8( tvb, offset + NB_DATA1); switch (status_request) { case 0: proto_tree_add_text(tree, tvb, offset + NB_DATA1, 1, "Status request: NetBIOS 1.x or 2.0"); break; case 1: proto_tree_add_text(tree, tvb, offset + NB_DATA1, 1, "Status request: NetBIOS 2.1, initial status request"); break; default: proto_tree_add_text(tree, tvb, offset + NB_DATA1, 1, "Status request: NetBIOS 2.1, %u names received so far", status_request); break; } nb_data2( hf_netb_status_buffer_len, tvb, offset, tree); nb_resp_corrl( tvb, offset, tree); netbios_add_name("Receiver's Name", tvb, offset + NB_RECVER_NAME, tree); netbios_add_name("Sender's Name", tvb, offset + NB_SENDER_NAME, tree); return 0; } static guint32 dissect_netb_terminate_trace( tvbuff_t *tvb _U_, int offset _U_, proto_tree *tree _U_) {/* Handle the TERMINATE TRACE command */ /* * XXX - are any of the fields in this message significant? * The IBM NetBIOS document shows them as "Reserved". */ return 0; } static guchar zeroes[10]; static guint32 dissect_netb_datagram( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the DATAGRAM command */ netbios_add_name("Receiver's Name", tvb, offset + NB_RECVER_NAME, tree); /* Weird. In some datagrams, this is 10 octets of 0, followed by a MAC address.... */ if (memcmp( tvb_get_ptr( tvb,offset + NB_SENDER_NAME, 10), zeroes, 10) == 0) { proto_tree_add_text( tree, tvb, offset + NB_SENDER_NAME + 10, 6, "Sender's MAC Address: %s", ether_to_str( tvb_get_ptr( tvb,offset + NB_SENDER_NAME + 10, 6))); } else { netbios_add_name("Sender's Name", tvb, offset + NB_SENDER_NAME, tree); } return 0; } static guint32 dissect_netb_datagram_bcast( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the DATAGRAM BROADCAST command */ /* We assume the same weirdness can happen here.... */ if ( memcmp( tvb_get_ptr( tvb,offset + NB_SENDER_NAME + 10, 6), zeroes, 10) == 0) { proto_tree_add_text( tree, tvb, offset + NB_SENDER_NAME + 10, 6, "Sender's Node Address: %s", ether_to_str( tvb_get_ptr( tvb,offset + NB_SENDER_NAME + 10, 6))); } else { netbios_add_name("Sender's Name", tvb, offset + NB_SENDER_NAME, tree); } return 0; } static guint32 dissect_netb_name_query( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the NAME QUERY command */ guint8 local_session_number = tvb_get_guint8( tvb, offset + NB_DATA2); if (local_session_number == 0) { proto_tree_add_text( tree, tvb, offset + NB_DATA2, 1, "Local Session No.: 0 (FIND.NAME request)"); } else { proto_tree_add_text( tree, tvb, offset + NB_DATA2, 1, "Local Session No.: 0x%02x", local_session_number); } nb_call_name_type( tvb, offset, tree); nb_resp_corrl( tvb, offset, tree); netbios_add_name("Query Name", tvb, offset + NB_RECVER_NAME, tree); if (local_session_number != 0) { netbios_add_name("Sender's Name", tvb, offset + NB_SENDER_NAME, tree); } return 0; } static guint32 dissect_netb_add_name_resp( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the ADD NAME RESPONSE command */ nb_data1( hf_netb_status, tvb, offset, tree); nb_data2( hf_netb_name_type, tvb, offset, tree); nb_xmit_corrl( tvb, offset, tree); netbios_add_name("Name to be added", tvb, offset + NB_RECVER_NAME, tree); netbios_add_name("Name to be added", tvb, offset + NB_SENDER_NAME, tree); return 0; } static guint32 dissect_netb_name_resp( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the NAME RECOGNIZED command */ guint8 local_session_number = tvb_get_guint8( tvb, offset + NB_DATA2); switch (local_session_number) { case 0x00: proto_tree_add_text( tree, tvb, offset + NB_DATA2, 1, "State of name: No LISTEN pending, or FIND.NAME response"); break; case 0xFF: proto_tree_add_text( tree, tvb, offset + NB_DATA2, 1, "State of name: LISTEN pending, but insufficient resources to establish session"); break; default: proto_tree_add_text( tree, tvb, offset + NB_DATA2, 1, "Local Session No.: 0x%02x", local_session_number); break; } nb_call_name_type( tvb, offset, tree); nb_xmit_corrl( tvb, offset, tree); if (local_session_number != 0x00 && local_session_number != 0xFF) nb_resp_corrl(tvb, offset, tree); netbios_add_name("Receiver's Name", tvb, offset + NB_RECVER_NAME, tree); if (local_session_number != 0x00 && local_session_number != 0xFF) { netbios_add_name("Sender's Name", tvb, offset + NB_SENDER_NAME, tree); } return 0; } static guint32 dissect_netb_status_resp( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the STATUS RESPONSE command */ guint8 status_response = tvb_get_guint8( tvb, offset + NB_DATA1); proto_item *td2; proto_tree *data2_tree; guint16 data2; nb_call_name_type( tvb, offset, tree); if (status_response == 0) { proto_tree_add_text(tree, tvb, offset + NB_DATA1, 1, "Status response: NetBIOS 1.x or 2.0"); } else { proto_tree_add_text(tree, tvb, offset + NB_DATA1, 1, "Status response: NetBIOS 2.1, %u names sent so far", status_response); } data2 = tvb_get_letohs( tvb, offset + NB_DATA2); td2 = proto_tree_add_text(tree, tvb, offset + NB_DATA2, 2, "Status: 0x%04x", data2); data2_tree = proto_item_add_subtree(td2, ett_netb_status); if (data2 & 0x8000) { proto_tree_add_text(data2_tree, tvb, offset, 2, "%s", decode_boolean_bitfield(data2, 0x8000, 8*2, "Data length exceeds maximum frame size", NULL)); } if (data2 & 0x4000) { proto_tree_add_text(data2_tree, tvb, offset, 2, "%s", decode_boolean_bitfield(data2, 0x4000, 8*2, "Data length exceeds user's buffer", NULL)); } proto_tree_add_text(data2_tree, tvb, offset, 2, "%s", decode_numeric_bitfield(data2, 0x3FFF, 2*8, "Status data length = %u")); nb_xmit_corrl( tvb, offset, tree); netbios_add_name("Receiver's Name", tvb, offset + NB_RECVER_NAME, tree); netbios_add_name("Sender's Name", tvb, offset + NB_SENDER_NAME, tree); return 0; } static guint32 dissect_netb_data_ack( tvbuff_t* tvb, int offset, proto_tree *tree) {/* Handle the DATA ACK command */ nb_xmit_corrl( tvb, offset, tree); nb_remote_session( tvb, offset, tree); nb_local_session( tvb, offset, tree); return 0; } static guint32 dissect_netb_data_first_middle( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the DATA FIRST MIDDLE command */ guint8 remote_session, local_session; /* * This is the first frame, or the middle frame, of a fragmented * packet. * * XXX - there are no sequence numbers, so we have to assume * that fragments arrive in order with no duplicates. * In fact, 802.2 LLC is supposed to handle that, so we * might have to have the LLC dissector do so (but the TCP * dissector doesn't currently handle out-of-order or duplicate * data, either). */ netbios_data_first_middle_flags( tvb, tree, offset + NB_FLAGS); nb_resync_indicator( tvb, offset, tree, "DATA FIRST MIDDLE"); nb_xmit_corrl( tvb, offset, tree); nb_resp_corrl( tvb, offset, tree); remote_session = nb_remote_session( tvb, offset, tree); local_session = nb_local_session( tvb, offset, tree); /* * Return a combination of the remote and local session numbers, * for use when reassembling. */ return (remote_session << 8) + local_session; } static guint32 dissect_netb_data_only_last( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the DATA ONLY LAST command */ guint8 remote_session, local_session; /* * This is a complete packet, or the last frame of a fragmented * packet. */ netbios_data_only_flags( tvb, tree, offset + NB_FLAGS); nb_resync_indicator( tvb, offset, tree, "DATA ONLY LAST"); nb_xmit_corrl( tvb, offset, tree); nb_resp_corrl( tvb, offset, tree); remote_session = nb_remote_session( tvb, offset, tree); local_session = nb_local_session( tvb, offset, tree); /* * Return a combination of the remote and local session numbers, * for use when reassembling. */ return (remote_session << 8) + local_session; } static guint32 dissect_netb_session_confirm( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the SESSION CONFIRM command */ netbios_add_ses_confirm_flags( tvb, tree, offset + NB_FLAGS); nb_data2( hf_netb_max_data_recv_size, tvb, offset, tree); nb_xmit_corrl( tvb, offset, tree); nb_resp_corrl( tvb, offset, tree); nb_remote_session( tvb, offset, tree); nb_local_session( tvb, offset, tree); return 0; } static guint32 dissect_netb_session_end( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the SESSION END command */ nb_data2( hf_netb_termination_indicator, tvb, offset, tree); nb_remote_session( tvb, offset, tree); nb_local_session( tvb, offset, tree); return 0; } static guint32 dissect_netb_session_init( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the SESSION INITIALIZE command */ netbios_add_session_init_flags( tvb, tree, offset + NB_FLAGS); nb_data2( hf_netb_max_data_recv_size, tvb, offset, tree); nb_resp_corrl( tvb, offset, tree); nb_xmit_corrl( tvb, offset, tree); nb_remote_session( tvb, offset, tree); nb_local_session( tvb, offset, tree); return 0; } static guint32 dissect_netb_no_receive( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the NO RECEIVE command */ netbios_no_receive_flags( tvb, tree, offset + NB_FLAGS); nb_data2( hf_netb_num_data_bytes_accepted, tvb, offset, tree); nb_remote_session( tvb, offset, tree); nb_local_session( tvb, offset, tree); return 0; } static guint32 dissect_netb_receive_outstanding( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the RECEIVE OUTSTANDING command */ nb_data2( hf_netb_num_data_bytes_accepted, tvb, offset, tree); nb_remote_session( tvb, offset, tree); nb_local_session( tvb, offset, tree); return 0; } static guint32 dissect_netb_receive_continue( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the RECEIVE CONTINUE command */ nb_xmit_corrl( tvb, offset, tree); nb_remote_session( tvb, offset, tree); nb_local_session( tvb, offset, tree); return 0; } static guint32 dissect_netb_session_alive( tvbuff_t *tvb, int offset, proto_tree *tree) {/* Handle the SESSION ALIVE command */ /* * XXX - all the fields are claimed to be "Reserved", but * the session numbers appear to be non-zero in at least * one capture, and they do appear to match session numbers * in other messages, and I'd expect that you had to identify * sessions in this message in any case. * * We show only those fields. */ nb_remote_session( tvb, offset, tree); nb_local_session( tvb, offset, tree); return 0; } /************************************************************************/ /* */ /* The table routines called by the top level to handle commands */ /* */ /************************************************************************/ static guint32 (*dissect_netb[])(tvbuff_t *, int, proto_tree *) = { dissect_netb_add_group_name, /* Add Group Name 0x00 */ dissect_netb_add_name, /* Add Name 0x01 */ dissect_netb_name_in_conflict,/* Name In Conflict 0x02 */ dissect_netb_status_query, /* Status Query 0x03 */ dissect_netb_unknown, /* unknown 0x04 */ dissect_netb_unknown, /* unknown 0x05 */ dissect_netb_unknown, /* unknown 0x06 */ dissect_netb_terminate_trace, /* Terminate Trace 0x07 */ dissect_netb_datagram, /* Datagram 0x08 */ dissect_netb_datagram_bcast, /* Datagram Broadcast 0x09 */ dissect_netb_name_query, /* Name Query 0x0A */ dissect_netb_unknown, /* unknown 0x0B */ dissect_netb_unknown, /* unknown 0x0C */ dissect_netb_add_name_resp, /* Add Name Response 0x0D */ dissect_netb_name_resp, /* Name Recognized 0x0E */ dissect_netb_status_resp, /* Status Response 0x0F */ dissect_netb_unknown, /* unknown 0x10 */ dissect_netb_unknown, /* unknown 0x11 */ dissect_netb_unknown, /* unknown 0x12 */ dissect_netb_terminate_trace, /* Terminate Trace 0x13 */ dissect_netb_data_ack, /* Data Ack 0x14 */ dissect_netb_data_first_middle,/* Data First Middle 0x15 */ dissect_netb_data_only_last, /* Data Only Last 0x16 */ dissect_netb_session_confirm, /* Session Confirm 0x17 */ dissect_netb_session_end, /* Session End 0x18 */ dissect_netb_session_init, /* Session Initialize 0x19 */ dissect_netb_no_receive, /* No Receive 0x1A */ dissect_netb_receive_outstanding,/* Receive Outstanding 0x1B */ dissect_netb_receive_continue,/* Receive Continue 0x1C */ dissect_netb_unknown, /* unknown 0x1D */ dissect_netb_unknown, /* unknown 0x1E */ dissect_netb_session_alive, /* Session Alive 0x1f */ dissect_netb_unknown, }; static heur_dissector_list_t netbios_heur_subdissector_list; void dissect_netbios_payload(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { /* * Try the heuristic dissectors for NetBIOS; if none of them * accept the packet, dissect it as data. */ if (!dissector_try_heuristic(netbios_heur_subdissector_list, tvb, pinfo, tree)) call_dissector(data_handle,tvb, pinfo, tree); } static void dissect_netbios(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { proto_tree *netb_tree = NULL; proto_item *ti; guint16 hdr_len, command; char *command_name; char name[(NETBIOS_NAME_LEN - 1)*4 + 1]; int name_type; guint16 session_id; gboolean save_fragmented; int len; fragment_data *fd_head; tvbuff_t *next_tvb; int offset = 0; /* load the display labels */ if (check_col(pinfo->cinfo, COL_PROTOCOL)) col_set_str(pinfo->cinfo, COL_PROTOCOL, "NetBIOS"); /* Find NetBIOS marker EFFF, this is done because I have seen an extra LLC */ /* byte on our network. This only checks for one extra LLC byte. */ if ( 0xefff != tvb_get_letohs(tvb, 2)){ ++offset; if ( 0xefff != tvb_get_letohs(tvb, 3)){ if (check_col( pinfo->cinfo, COL_INFO)) /* print bad packet */ col_set_str( pinfo->cinfo, COL_INFO, "Bad packet, no 0xEFFF marker"); return; /* this is an unknow packet, no marker */ } } hdr_len = tvb_get_letohs(tvb, offset + NB_LENGTH); command = tvb_get_guint8( tvb, offset + NB_COMMAND); /* limit command so no table overflows */ command = MIN( command, sizeof( dissect_netb)/ sizeof(void *)); if (check_col( pinfo->cinfo, COL_INFO)) { /* print command name */ command_name = val_to_str(command, cmd_vals, "Unknown (0x%02x)"); switch ( command ) { case NB_NAME_QUERY: name_type = get_netbios_name( tvb, offset + 12, name); col_add_fstr( pinfo->cinfo, COL_INFO, "%s for %s<%02x>", command_name, name, name_type); break; case NB_NAME_RESP: case NB_ADD_NAME: case NB_ADD_GROUP: name_type = get_netbios_name( tvb, offset + 28, name); col_add_fstr( pinfo->cinfo, COL_INFO, "%s - %s<%02x>", command_name, name, name_type); break; default: col_add_fstr( pinfo->cinfo, COL_INFO, "%s", command_name); break; } } if ( tree) { ti = proto_tree_add_item(tree, proto_netbios, tvb, 0, hdr_len, FALSE); netb_tree = proto_item_add_subtree(ti, ett_netb); proto_tree_add_uint_format(netb_tree, hf_netb_hdr_len, tvb, offset, 2, hdr_len, "Length: %d bytes", hdr_len); proto_tree_add_text(netb_tree, tvb, offset + 2, 2, "Delimiter: EFFF (NetBIOS)"); proto_tree_add_uint(netb_tree, hf_netb_cmd, tvb, offset + NB_COMMAND, 1, command); } /* if command in table range */ if ( command < sizeof( dissect_netb)/ sizeof(void *)) { /* branch to handle commands */ session_id = (dissect_netb[ command])( tvb, offset, netb_tree); offset += hdr_len; /* move past header */ save_fragmented = pinfo->fragmented; /* * Process user data in frames that have it. */ switch (command) { case NB_DATAGRAM: case NB_DATAGRAM_BCAST: /* * No fragmentation here. */ next_tvb = tvb_new_subset(tvb, offset, -1, -1); dissect_netbios_payload(next_tvb, pinfo, tree); break; case NB_DATA_FIRST_MIDDLE: case NB_DATA_ONLY_LAST: /* * Possibly fragmented. */ len = tvb_reported_length_remaining(tvb, offset); if (netbios_defragment && tvb_bytes_exist(tvb, offset, len)) { fd_head = fragment_add_seq_next(tvb, offset, pinfo, session_id, netbios_fragment_table, netbios_reassembled_table, len, command == NB_DATA_FIRST_MIDDLE); if (fd_head != NULL) { if (fd_head->next != NULL) { next_tvb = tvb_new_real_data(fd_head->data, fd_head->len, fd_head->len); tvb_set_child_real_data_tvbuff(tvb, next_tvb); add_new_data_source(pinfo, next_tvb, "Reassembled NetBIOS"); /* Show all fragments. */ if (tree) { show_fragment_seq_tree(fd_head, &netbios_frag_items, netb_tree, pinfo, next_tvb); } } else { next_tvb = tvb_new_subset(tvb, offset, -1, -1); } } else { next_tvb = NULL; } } else { /* * Dissect this, regardless of whether * it's NB_DATA_FIRST_MIDDLE or * NB_DATA_ONLY_LAST. * * XXX - it'd be nice to show * NB_DATA_FIRST_MIDDLE as a fragment * if it's not the first fragment (i.e., * MIDDLE rather than FIRST), and show * NB_DATA_ONLY_LAST as a fragment if * it's part of a fragmented datagram * (i.e, LAST rather than ONLY), but * we'd have to do reassembly to * be able to determine that. */ next_tvb = tvb_new_subset(tvb, offset, -1, -1); } if (next_tvb != NULL) dissect_netbios_payload(next_tvb, pinfo, tree); else { next_tvb = tvb_new_subset (tvb, offset, -1, -1); call_dissector(data_handle, next_tvb, pinfo, tree); } break; } } } static void netbios_init(void) { /* * Initialize the fragment and reassembly tables. */ fragment_table_init(&netbios_fragment_table); reassembled_table_init(&netbios_reassembled_table); } void proto_register_netbios(void) { static gint *ett[] = { &ett_netb, &ett_netb_name, &ett_netb_flags, &ett_netb_status, &ett_netb_fragments, &ett_netb_fragment, }; static hf_register_info hf_netb[] = { { &hf_netb_cmd, { "Command", "netbios.command", FT_UINT8, BASE_HEX, VALS(cmd_vals), 0x0, "", HFILL }}, { &hf_netb_hdr_len, { "Header Length", "netbios.hdr_len", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_netb_xmit_corrl, { "Transmit Correlator", "netbios.xmit_corrl", FT_UINT16, BASE_HEX, NULL, 0x0, "", HFILL }}, { &hf_netb_resp_corrl, { "Response Correlator", "netbios.resp_corrl", FT_UINT16, BASE_HEX, NULL, 0x0, "", HFILL }}, { &hf_netb_call_name_type, { "Caller's Name Type", "netbios.call_name_type", FT_UINT8, BASE_HEX, VALS(name_types), 0x0, "", HFILL }}, { &hf_netb_nb_name_type, { "NetBIOS Name Type", "netbios.nb_name_type", FT_UINT8, BASE_HEX, VALS(nb_name_type_vals), 0x0, "", HFILL }}, { &hf_netb_nb_name, { "NetBIOS Name", "netbios.nb_name", FT_STRING, BASE_NONE, NULL, 0x0, "", HFILL }}, { &hf_netb_ack, { "Acknowledge", "netbios.ack", FT_BOOLEAN, 8, TFS( &flags_set), 0x08, "", HFILL }}, { &hf_netb_ack_with_data, { "Acknowledge with data", "netbios.ack_with_data", FT_BOOLEAN, 8, TFS( &flags_allowed), 0x04, "", HFILL }}, { &hf_netb_ack_expected, { "Acknowledge expected", "netbios.ack_expected", FT_BOOLEAN, 8, TFS( &flags_yes_no), 0x02, "", HFILL }}, { &hf_netb_recv_cont_req, { "RECEIVE_CONTINUE requested", "netbios.recv_cont_req", FT_BOOLEAN, 8, TFS( &flags_yes_no), 0x01, "", HFILL }}, { &hf_netb_send_no_ack, { "Handle SEND.NO.ACK", "netbios.send_no_ack", FT_BOOLEAN, 8, TFS( &flags_yes_no), 0x80, "", HFILL }}, { &hf_netb_version, { "NetBIOS Version", "netbios.version", FT_BOOLEAN, 8, TFS( &netb_version_str), 0x01, "", HFILL }}, { &hf_netb_largest_frame, { "Largest Frame", "netbios.largest_frame", FT_UINT8, BASE_DEC, VALS(max_frame_size_vals), 0x0E, "", HFILL }}, { &hf_netb_status_buffer_len, { "Length of status buffer", "netbios.status_buffer_len", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_netb_status, { "Status", "netbios.status", FT_UINT8, BASE_DEC, VALS(status_vals), 0x0, "", HFILL }}, { &hf_netb_name_type, { "Name type", "netbios.name_type", FT_UINT16, BASE_DEC, VALS(name_types), 0x0, "", HFILL }}, { &hf_netb_max_data_recv_size, { "Maximum data receive size", "netbios.max_data_recv_size", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_netb_termination_indicator, { "Termination indicator", "netbios.termination_indicator", FT_UINT16, BASE_HEX, VALS(termination_indicator_vals), 0x0, "", HFILL }}, { &hf_netb_num_data_bytes_accepted, { "Number of data bytes accepted", "netbios.num_data_bytes_accepted", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_netb_local_ses_no, { "Local Session No.", "netbios.local_session", FT_UINT8, BASE_HEX, NULL, 0x0, "", HFILL }}, { &hf_netb_remote_ses_no, { "Remote Session No.", "netbios.remote_session", FT_UINT8, BASE_HEX, NULL, 0x0, "", HFILL }}, { &hf_netb_data1, { "DATA1 value", "netbios.data1", FT_UINT8, BASE_HEX, NULL, 0x0, "", HFILL }}, { &hf_netb_data2, { "DATA2 value", "netbios.data2", FT_UINT16, BASE_HEX, NULL, 0x0, "", HFILL }}, { &hf_netb_fragment_overlap, { "Fragment overlap", "netbios.fragment.overlap", FT_BOOLEAN, BASE_NONE, NULL, 0x0, "Fragment overlaps with other fragments", HFILL }}, { &hf_netb_fragment_overlap_conflict, { "Conflicting data in fragment overlap", "netbios.fragment.overlap.conflict", FT_BOOLEAN, BASE_NONE, NULL, 0x0, "Overlapping fragments contained conflicting data", HFILL }}, { &hf_netb_fragment_multiple_tails, { "Multiple tail fragments found", "netbios.fragment.multipletails", FT_BOOLEAN, BASE_NONE, NULL, 0x0, "Several tails were found when defragmenting the packet", HFILL }}, { &hf_netb_fragment_too_long_fragment, { "Fragment too long", "netbios.fragment.toolongfragment", FT_BOOLEAN, BASE_NONE, NULL, 0x0, "Fragment contained data past end of packet", HFILL }}, { &hf_netb_fragment_error, {"Defragmentation error", "netbios.fragment.error", FT_FRAMENUM, BASE_NONE, NULL, 0x0, "Defragmentation error due to illegal fragments", HFILL }}, { &hf_netb_fragment, { "NetBIOS Fragment", "netbios.fragment", FT_FRAMENUM, BASE_NONE, NULL, 0x0, "NetBIOS Fragment", HFILL }}, { &hf_netb_fragments, { "NetBIOS Fragments", "netbios.fragments", FT_NONE, BASE_NONE, NULL, 0x0, "NetBIOS Fragments", HFILL }}, }; module_t *netbios_module; proto_netbios = proto_register_protocol("NetBIOS", "NetBIOS", "netbios"); proto_register_subtree_array(ett, array_length(ett)); proto_register_field_array(proto_netbios, hf_netb, array_length(hf_netb)); register_heur_dissector_list("netbios", &netbios_heur_subdissector_list); netbios_module = prefs_register_protocol(proto_netbios, NULL); prefs_register_bool_preference(netbios_module, "defragment", "Defragment all NetBIOS messages spanning multiple frames", "Whether the NetBIOS dissector should defragment all messages spanning multiple frames", &netbios_defragment); register_init_routine(netbios_init); } void proto_reg_handoff_netbios(void) { dissector_handle_t netbios_handle; netbios_handle = create_dissector_handle(dissect_netbios, proto_netbios); dissector_add("llc.dsap", SAP_NETBIOS, netbios_handle); data_handle = find_dissector("data"); }