/* 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 1.4 1999/09/02 23:17:56 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 #ifdef HAVE_SYS_TYPES_H # include #endif #include #include #include #include "packet.h" #include "packet-dns.h" #include "packet-netbios.h" #include "util.h" /* Netbios command numbers */ #define NB_ADD_GROUP 0x00 #define NB_ADD_NAME 0x01 #define NB_DATAGRAM 0x08 #define NB_NAME_QUERY 0x0a #define NB_NAME_RESP 0x0e #define NB_DATA_ACK 0x14 #define NB_DATA_ONLY_LAST 0x16 #define NB_SESSION_CONFIRM 0x17 #define NB_SESSION_INIT 0x19 #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; /* a number to bit image table */ static char *bit_field_str[] = { "000", "001", "010", "011", "100", "101", "110", "111"}; /* the strings for the station type, used by get_netbios_name function */ char *name_type_str[] = { "Workstation/Redirector", /* 0x00 */ "Browser", /* 0x01 */ "Unknown", "Messenger service/Main name", /* 0x03 */ "Unknown", "Forwarded name", /* 0x05 */ "RAS Server service", /* 0x06 */ "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", /* 0x10 */ "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "PDC Domain name", /* 0x1b */ "BDC Domain name", /* 0x1c */ "Master Browser backup", /* 0x1d */ "Browser Election Service", /* 0x1e */ "Net DDE Service", /* 0x1f */ "Server service", /* 0x20 */ "RAS client service", /* 0x21 */ "Unknown", /* need 'Unknown' as last entry (for limiting stuff) */ }; static int nb_name_type_max = (sizeof name_type_str / sizeof name_type_str[0]) - 1; /* the strings for the command types */ char *CommandName[] = { "Add Group Query", /* 0x00 */ "Add Name Query", /* 0x01 */ "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Datagram", /* 0x08 */ "Unknown", "Name Query", /* 0x0A */ "Unknown", "Unknown", "Unknown", "Name Recognized", /* 0x0E */ "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Data Ack", /* 0x14 */ "Unknown", "Data Only Last", /* 0x16 */ "Session Confirm", /* 0x17 */ "Unknown", "Session Initialize", /* 0x19 */ "Unknown", "Unknown", "Unknown", "Unknown", "Unknown", "Session Alive", /* 0x1f */ }; void capture_netbios(const u_char *pd, int offset, guint32 cap_len, packet_counts *ld) { ld->netbios++; } static guint get_netbios_name(const u_char *data_ptr, int offset, char *name_ret) {/* Extract the name string and name type. Return the name string in */ /* name_ret and return the name_type. */ int i; char name_type = *(data_ptr + offset + 15); const char *name_ptr = data_ptr + offset; for( i = 0; i <16; ++i){ if ( 0x20 == (*name_ret++ = *name_ptr++)) /* exit if space */ break; } *name_ret = 0; return (guint)name_type; } void netbios_add_name( char* label, const u_char *pd, int offset, int nb_offset, proto_tree *tree) {/* add a name field display tree. Display the name and station type in sub-tree */ /* NOTE: offset = offset to start of netbios header */ /* nb_offset = offset inside of netbios header */ proto_tree *field_tree; proto_item *tf; char name_str[ 17]; int name_type; /* decode the name field */ name_type = get_netbios_name( pd, nb_offset, name_str); if ( nb_name_type_max < name_type) /* limit type value */ name_type = nb_name_type_max; tf = proto_tree_add_text( tree, offset + nb_offset, 16, "%s: %s (%s)", label, name_str, name_type_str[name_type]); field_tree = proto_item_add_subtree( tf, ETT_NETB_NAME); proto_tree_add_text( field_tree, offset + nb_offset, 15, "%s", name_str); proto_tree_add_text( field_tree, offset + nb_offset + 15, 1, "0x%0x (%s)", name_type, name_type_str[ name_type]); } static void netbios_add_flags( const u_char *pd, proto_tree *tree, int offset) { proto_tree *field_tree; proto_item *tf; guint flags = *(pd + offset); /* decode the flag field */ tf = proto_tree_add_text( tree, offset, 1, "Flags: 0x%02x", flags); field_tree = proto_item_add_subtree(tf, ETT_NETB_FLAGS); proto_tree_add_text( field_tree, offset, 1, "%s%s", decode_boolean_bitfield(flags, 0x80, 8, "No", ""), " NO.ACK indicator"); proto_tree_add_text(field_tree, offset, 1, ".... %s. = Largest Frame Size = %d", bit_field_str[(flags & 0x0e) >> 1], ((flags & 0x0e) >> 1)); proto_tree_add_text(field_tree, offset, 1, "%s", decode_boolean_bitfield( flags, 0x01, 8, "Version 2.0 or higher", "Pre version 2.0")); } static void netbios_add_ses_confirm_flags( const u_char *pd, proto_tree *tree, int offset) { proto_tree *field_tree; proto_item *tf; guint flags = *(pd + offset); /* decode the flag field */ tf = proto_tree_add_text( tree, offset, 1, "Flags: 0x%02x", flags); field_tree = proto_item_add_subtree( tf, ETT_NETB_FLAGS); proto_tree_add_text(field_tree, offset, 1, "%s%s", decode_boolean_bitfield(flags, 0x80, 8, "No", ""), " NO.ACK indicator"); proto_tree_add_text(field_tree, offset, 1, "%s", decode_boolean_bitfield(flags, 0x01, 8, "Pre version 2.0", "Version 2.0 or higher")); } static void netbios_data_only_flags( const u_char *pd, proto_tree *tree, int offset) { proto_tree *field_tree; proto_item *tf; guint flags = *(pd + offset); /* decode the flag field for data_only packet*/ tf = proto_tree_add_text( tree, offset, 1, "Flags: 0x%02x", flags); field_tree = proto_item_add_subtree(tf, ETT_NETB_FLAGS); proto_tree_add_text(field_tree, offset, 1, "%s%s", decode_boolean_bitfield(flags, 0x08, 8, "", "No "), "Acknowledge_Included"); proto_tree_add_text(field_tree, offset, 1, "%s%s", decode_boolean_bitfield(flags, 0x04, 8, "", "No "), "Ack_with_data_allowed"); proto_tree_add_text(field_tree, offset, 1, "%s%s", decode_boolean_bitfield(flags, 0x02, 8, "", "No "), "NO.ACK indicator"); } /************************************************************************/ /* */ /* The routines to display the netbios field values in the tree */ /* */ /************************************************************************/ static void nb_xmit_corrl(const u_char *data_ptr, int offset, proto_tree *tree) {/* display the transmit correlator */ proto_tree_add_text( tree, offset + NB_XMIT_CORL, 2, "Transmit Correlator: 0x%04x", pletohs( data_ptr + NB_XMIT_CORL)); } static void nb_resp_corrl(const u_char *data_ptr, int offset, proto_tree *tree) {/* display the response correlator */ proto_tree_add_text( tree, offset + NB_RESP_CORL, 2, "Response Correlator: 0x%04x", pletohs( data_ptr + NB_RESP_CORL)); } static void nb_call_name_type(const u_char *data_ptr, int offset, proto_tree *tree) {/* display the call name type */ int name_type_value = MIN(*(data_ptr + NB_CALL_NAME_TYPE), nb_name_type_max); proto_tree_add_text( tree, offset + NB_CALL_NAME_TYPE, 1, "Caller's Name Type.: 0x%02x (%s)", *(data_ptr + NB_CALL_NAME_TYPE), name_type_str[ name_type_value]); } static void nb_local_session(const u_char *data_ptr, int offset, proto_tree *tree) {/* add the local session to tree */ proto_tree_add_text( tree, offset +NB_LOCAL_SES, 1, "Local Session No.: 0x%02d", *(data_ptr + NB_LOCAL_SES)); } static void nb_remote_session(const u_char *data_ptr, int offset, proto_tree *tree) {/* add the remote session to tree */ proto_tree_add_text( tree, offset +NB_RMT_SES, 1, "Remote Session No.: 0x%02d", *(data_ptr + NB_RMT_SES)); } static void nb_data1( char *label, const u_char *data_ptr, int offset, proto_tree *tree) {/* add the DATA1 to tree with format string = label */ proto_tree_add_text( tree, offset + NB_DATA1, 1, label, *(data_ptr + NB_DATA1)); } static void nb_data2( char *label, int len, const u_char *data_ptr, int offset, proto_tree *tree) {/* add the DATA2 to tree with format string = label and length of len */ int value = (len == 1 ? *(data_ptr + NB_DATA2) : pletohs( data_ptr + NB_DATA2)); proto_tree_add_text( tree, offset +NB_DATA2, len, label, value); } /************************************************************************/ /* */ /* The routines called by the top level to handle individual commands */ /* */ /************************************************************************/ static void dissect_netb_unknown(const u_char *data_ptr, int offset, frame_data *fd, proto_tree *tree) {/* Handle any unknow commands, do nothing */ //$$ dissect_data( data_ptr, offset + NB_COMMAND + 1, fd, tree); } static void dissect_netb_add_group(const u_char *data_ptr, int offset, frame_data *fd, proto_tree *tree) {/* Handle the ADD GROUP command */ nb_resp_corrl( data_ptr, offset, tree); netbios_add_name( "Group to add", data_ptr, offset, NB_SENDER_NAME, tree); } static void dissect_netb_add_name(const u_char *data_ptr, int offset, frame_data *fd, proto_tree *tree) {/* Handle the ADD NAME command */ nb_resp_corrl( data_ptr, offset, tree); netbios_add_name( "Name to add", data_ptr, offset, NB_SENDER_NAME, tree); } static void dissect_netb_name_query(const u_char *data_ptr, int offset, frame_data *fd, proto_tree *tree) {/* Handle the NAME QUERY command */ nb_data2( "Local Session No.: 0x%02x", 1, data_ptr, offset, tree); nb_call_name_type( data_ptr, offset, tree); netbios_add_name( "Query Name", data_ptr, offset, NB_RECVER_NAME, tree); netbios_add_name( "Sender's Name", data_ptr, offset, NB_SENDER_NAME, tree); } static void dissect_netb_name_resp(const u_char *data_ptr, int offset, frame_data *fd, proto_tree *tree) {/* Handle the NAME RESPONSE command */ nb_data2( "Local Session No.: 0x%02x", 1, data_ptr, offset, tree); nb_call_name_type( data_ptr, offset, tree); nb_xmit_corrl( data_ptr, offset, tree); nb_resp_corrl( data_ptr, offset, tree); netbios_add_name( "Receiver's Name", data_ptr, offset, NB_RECVER_NAME, tree); netbios_add_name( "Sender's Name", data_ptr, offset, NB_SENDER_NAME, tree); } static void dissect_netb_session_init(const u_char *data_ptr, int offset, frame_data *fd, proto_tree *tree) {/* Handle the SESSION INITIATE command */ netbios_add_flags( data_ptr, tree, offset + NB_FLAGS); nb_data2( "Max data recv size: %d", 2, data_ptr, offset, tree); nb_resp_corrl( data_ptr, offset, tree); nb_xmit_corrl( data_ptr, offset, tree); nb_remote_session( data_ptr, offset, tree); nb_local_session( data_ptr, offset, tree); } static void dissect_netb_session_confirm(const u_char *data_ptr, int offset, frame_data *fd, proto_tree *tree) {/* Handle the SESSION CONFIRM command */ netbios_add_ses_confirm_flags( data_ptr, tree, offset + NB_FLAGS); nb_data2( "Max data recv size: %d", 2, data_ptr, offset, tree); nb_resp_corrl( data_ptr, offset, tree); nb_xmit_corrl( data_ptr, offset, tree); nb_remote_session( data_ptr, offset, tree); nb_local_session( data_ptr, offset, tree); } static void dissect_netb_data_only_last(const u_char *data_ptr, int offset, frame_data *fd, proto_tree *tree) {/* Handle the DATA ONLY LAST command */ netbios_data_only_flags( data_ptr, tree, offset + NB_FLAGS); nb_data2( "Re-sync indicator: %d", 2, data_ptr, offset, tree); nb_resp_corrl( data_ptr, offset, tree); nb_remote_session( data_ptr, offset, tree); nb_local_session( data_ptr, offset, tree); } static void dissect_netb_datagram(const u_char *data_ptr, int offset, frame_data *fd, proto_tree *tree) {/* Handle the DATAGRAM command */ nb_data1( "Data1: 0x%02x", data_ptr, offset, tree); nb_data2( "Data2: 0x%04x", 2, data_ptr, offset, tree); nb_xmit_corrl( data_ptr, offset, tree); nb_resp_corrl( data_ptr, offset, tree); netbios_add_name( "Receiver's Name", data_ptr, offset, NB_RECVER_NAME, tree); netbios_add_name( "Sender's Name", data_ptr, offset, NB_SENDER_NAME, tree); } static void dissect_netb_data_ack(const u_char *data_ptr, int offset, frame_data *fd, proto_tree *tree) {/* Handle the DATA ACK command */ netbios_data_only_flags( data_ptr, tree, offset + NB_FLAGS); nb_xmit_corrl( data_ptr, offset, tree); nb_remote_session( data_ptr, offset, tree); nb_local_session( data_ptr, offset, tree); } /************************************************************************/ /* */ /* The table routines called by the top level to handle commands */ /* */ /************************************************************************/ void (*dissect_netb[])(const u_char *, int, frame_data *, proto_tree *) = { dissect_netb_add_group, /* add_group 0x00 */ dissect_netb_add_name, /* add_name 0x01 */ dissect_netb_unknown, /* unknown 0x02 */ dissect_netb_unknown, /* unknown 0x03 */ dissect_netb_unknown, /* unknown 0x04 */ dissect_netb_unknown, /* unknown 0x05 */ dissect_netb_unknown, /* unknown 0x06 */ dissect_netb_unknown, /* unknown 0x07 */ dissect_netb_datagram, /* Datagram 0x08 */ dissect_netb_unknown, /* unknown 0x09 */ dissect_netb_name_query, /* Name Query 0x0A */ dissect_netb_unknown, /* unknown 0x0B */ dissect_netb_unknown, /* unknown 0x0C */ dissect_netb_unknown, /* unknown 0x0D */ dissect_netb_name_resp, /* Name Resp 0x0E */ dissect_netb_unknown, /* unknown 0x0F */ dissect_netb_unknown, /* unknown 0x10 */ dissect_netb_unknown, /* unknown 0x11 */ dissect_netb_unknown, /* unknown 0x12 */ dissect_netb_unknown, /* unknown 0x13 */ dissect_netb_data_ack, /* Data Ack 0x14 */ dissect_netb_unknown, /* unknown 0x15 */ dissect_netb_data_only_last, /* Data Only Last 0x16 */ dissect_netb_session_confirm, /* Session Confirm 0x17 */ dissect_netb_unknown, /* unknown 0x18 */ dissect_netb_session_init, /* Session Initialize 0x19 */ dissect_netb_unknown, /* unknown 0x1A */ dissect_netb_unknown, /* unknown 0x1B */ dissect_netb_unknown, /* unknown 0x1C */ dissect_netb_unknown, /* unknown 0x1D */ dissect_netb_unknown, /* unknown 0x1E */ dissect_netb_unknown, /* Session Alive 0x1f (nothing to do) */ }; void dissect_netbios(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) { const u_char *nb_data_ptr; proto_tree *netb_tree; proto_item *ti; guint16 hdr_len, command; char name[17]; nb_data_ptr = &pd[offset]; /* 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 (( *(nb_data_ptr + 2) != 0xff) || ( *(nb_data_ptr + 3) != 0xef)){ ++nb_data_ptr; /** marker not found shift one byte */ ++offset; if (( *(nb_data_ptr + 2) != 0xff) || ( *(nb_data_ptr + 3) != 0xef)){ if (check_col(fd, COL_PROTOCOL)) col_add_str(fd, COL_PROTOCOL, "NetBIOS"); if (check_col(fd, COL_INFO)) /* print bad packet */ col_add_str(fd, COL_INFO, "Bad packet"); if (tree) { ti = proto_tree_add_item(tree, proto_netbios, offset, END_OF_FRAME, NULL); netb_tree = proto_item_add_subtree(ti, ETT_NETB); proto_tree_add_text( netb_tree, offset, END_OF_FRAME, "Data (%u bytes)", END_OF_FRAME); } return; } } /* To do: check for runts, errs, etc. */ hdr_len = pletohs( nb_data_ptr + NB_LENGTH); command = *(nb_data_ptr + NB_COMMAND); if ( command == NB_NAME_QUERY ) { get_netbios_name( pd, offset + 12, name); } if ( command == NB_NAME_RESP ){ get_netbios_name( pd, offset + 28, name); } if (check_col(fd, COL_PROTOCOL)) col_add_str(fd, COL_PROTOCOL, "NetBIOS"); if (check_col(fd, COL_INFO)) { /* print command name */ if ( command == NB_NAME_QUERY) col_add_fstr(fd, COL_INFO, "%s for %s", CommandName[ command], name); else if ( command == NB_NAME_RESP) col_add_fstr(fd, COL_INFO, "%s - %s", CommandName[ command], name); else col_add_fstr(fd, COL_INFO, "%s", CommandName[ command]); } if (tree) { ti = proto_tree_add_item(tree, proto_netbios, offset, END_OF_FRAME, NULL); netb_tree = proto_item_add_subtree(ti, ETT_NETB); proto_tree_add_text(netb_tree, offset, 2, "Header Length: %d", hdr_len); proto_tree_add_text(netb_tree, offset + 2, 2, "Delimiter: EFFF (NetBIOS)"); proto_tree_add_text(netb_tree, offset + NB_COMMAND, 1, "Command: 0x%02x (%s)", command, CommandName[ command]); /* if command in table range */ if ( command < sizeof( dissect_netb)/ sizeof(void *)) /* branch to handle commands */ (dissect_netb[ command])( nb_data_ptr, offset, fd, netb_tree); } /* Test for SMB data */ if ( (END_OF_FRAME) > ( hdr_len + 4)){ /* if enough data */ nb_data_ptr += hdr_len; /* move past header */ if (( *nb_data_ptr == 0xff) && /* if SMB marker */ ( *(nb_data_ptr + 1) == 'S') && ( *(nb_data_ptr + 2) == 'M') && ( *(nb_data_ptr + 3) == 'B')) /* decode SMB */ dissect_smb(pd, offset + hdr_len, fd, tree, END_OF_FRAME - hdr_len); } /*$$$$ somewhere around here need to check for frame padding */ } void proto_register_netbios(void) { proto_netbios = proto_register_protocol("NetBIOS", "netbios"); }