/*
* netbios.c
*
* Copyright (C) 2009-2011 by ipoque GmbH
* Copyright (C) 2011-15 - ntop.org
*
* This file is part of nDPI, an open source deep packet inspection
* library based on the OpenDPI and PACE technology by ipoque GmbH
*
* nDPI is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* nDPI 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with nDPI. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include "ndpi_protocols.h"
#ifdef NDPI_PROTOCOL_NETBIOS
/* The function below has been inherited by tcpdump */
static int netbios_name_interpret(char *in, char *out, u_int out_len) {
int ret = 0, len;
char *b;
len = (*in++)/2;
b = out;
*out=0;
if(len > (out_len-1) || len < 1)
return(-1);
while (len--) {
if(in[0] < 'A' || in[0] > 'P' || in[1] < 'A' || in[1] > 'P') {
*out = 0;
break;
}
*out = ((in[0]-'A')<<4) + (in[1]-'A');
in += 2;
out++, ret++;
}
*out = 0;
/* Courtesy of Roberto F. De Luca <deluca@tandar.cnea.gov.ar> */
/* Trim trailing whitespace from the returned string */
for(out--; out>=b && *out==' '; out--) *out = '\0';
return(ret);
}
static void ndpi_int_netbios_add_connection(struct ndpi_detection_module_struct
*ndpi_struct, struct ndpi_flow_struct *flow)
{
ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_NETBIOS, NDPI_PROTOCOL_UNKNOWN);
}
void ndpi_search_netbios(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow)
{
struct ndpi_packet_struct *packet = &flow->packet;
// struct ndpi_id_struct *src=ndpi_struct->src;
// struct ndpi_id_struct *dst=ndpi_struct->dst;
u_int16_t dport;
if (packet->udp != NULL) {
dport = ntohs(packet->udp->dest);
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG, "netbios udp start\n");
/*check standard NETBIOS over udp to port 137 */
if ((dport == 137 || 0) && packet->payload_packet_len >= 50) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG, "found netbios port 137 and payload_packet_len 50\n");
if (ntohs(get_u_int16_t(packet->payload, 2)) == 0 &&
ntohs(get_u_int16_t(packet->payload, 4)) == 1 &&
ntohs(get_u_int16_t(packet->payload, 6)) == 0 &&
ntohs(get_u_int16_t(packet->payload, 8)) == 0 && ntohs(get_u_int16_t(packet->payload, 10)) == 0) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG, "found netbios with questions = 1 and answers = 0, authority = 0 \n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
if (packet->payload[2] == 0x80 &&
ntohs(get_u_int16_t(packet->payload, 4)) == 1 &&
ntohs(get_u_int16_t(packet->payload, 6)) == 0 &&
ntohs(get_u_int16_t(packet->payload, 8)) == 0 && ntohs(get_u_int16_t(packet->payload, 10)) == 1) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG, "found netbios with questions = 1 and answers, authority, additional = 0 \n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
if (ntohs(get_u_int16_t(packet->payload, 2)) == 0x4000 &&
ntohs(get_u_int16_t(packet->payload, 4)) == 1 &&
ntohs(get_u_int16_t(packet->payload, 6)) == 0 &&
ntohs(get_u_int16_t(packet->payload, 8)) == 0 && ntohs(get_u_int16_t(packet->payload, 10)) == 1) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG, "found netbios with questions = 1 and answers = 0, authority = 0 \n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
if (ntohs(get_u_int16_t(packet->payload, 2)) == 0x8400 &&
ntohs(get_u_int16_t(packet->payload, 4)) == 0 &&
ntohs(get_u_int16_t(packet->payload, 6)) == 1 &&
ntohs(get_u_int16_t(packet->payload, 8)) == 0 && ntohs(get_u_int16_t(packet->payload, 10)) == 0) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG,
"found netbios with flag 8400 questions = 0 and answers = 1, authority, additional = 0 \n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
if (ntohs(get_u_int16_t(packet->payload, 2)) == 0x8500 &&
ntohs(get_u_int16_t(packet->payload, 4)) == 0 &&
ntohs(get_u_int16_t(packet->payload, 6)) == 1 &&
ntohs(get_u_int16_t(packet->payload, 8)) == 0 && ntohs(get_u_int16_t(packet->payload, 10)) == 0) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG,
"found netbios with flag 8500 questions = 0 and answers = 1, authority, additional = 0 \n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
if (ntohs(get_u_int16_t(packet->payload, 2)) == 0x2910 &&
ntohs(get_u_int16_t(packet->payload, 4)) == 1 &&
ntohs(get_u_int16_t(packet->payload, 6)) == 0 &&
ntohs(get_u_int16_t(packet->payload, 8)) == 0 && ntohs(get_u_int16_t(packet->payload, 10)) == 1) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG,
"found netbios with flag 2910, questions = 1 and answers, authority=0, additional = 1 \n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
if (ntohs(get_u_int16_t(packet->payload, 2)) == 0xAD86 &&
ntohs(get_u_int16_t(packet->payload, 4)) == 0 &&
ntohs(get_u_int16_t(packet->payload, 6)) == 1 &&
ntohs(get_u_int16_t(packet->payload, 8)) == 0 && ntohs(get_u_int16_t(packet->payload, 10)) == 0) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG,
"found netbios with flag ad86 questions = 0 and answers = 1, authority, additional = 0 \n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
if (ntohs(get_u_int16_t(packet->payload, 2)) == 0x0110 &&
ntohs(get_u_int16_t(packet->payload, 4)) == 1 &&
ntohs(get_u_int16_t(packet->payload, 6)) == 0 &&
ntohs(get_u_int16_t(packet->payload, 8)) == 0 && ntohs(get_u_int16_t(packet->payload, 10)) == 0) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG,
"found netbios with flag 0110 questions = 1 and answers = 0, authority, additional = 0 \n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
if ((ntohs(get_u_int16_t(packet->payload, 2)) & 0xf800) == 0) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG, "possible netbios name query request\n");
if (get_u_int16_t(packet->payload, 4) == htons(1) &&
get_u_int16_t(packet->payload, 6) == 0 &&
get_u_int16_t(packet->payload, 8) == 0 && get_u_int16_t(packet->payload, 10) == 0) {
/* name is encoded as described in rfc883 */
u_int8_t name_length = packet->payload[12];
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"possible netbios name query request, one question\n");
if (packet->payload_packet_len == 12 + 1 + name_length + 1 + 2 + 2) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"possible netbios name query request, length matches\n");
/* null terminated? */
if (packet->payload[12 + name_length + 1] == 0 &&
get_u_int16_t(packet->payload, 12 + name_length + 2) == htons(0x0020) &&
get_u_int16_t(packet->payload, 12 + name_length + 4) == htons(0x0001)) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"found netbios name query request\n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
}
}
} else if ((ntohs(get_u_int16_t(packet->payload, 2)) & 0xf800) == 0x8000) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"possible netbios name query response\n");
if (get_u_int16_t(packet->payload, 4) == 0 &&
get_u_int16_t(packet->payload, 6) == htons(1) &&
get_u_int16_t(packet->payload, 8) == 0 && get_u_int16_t(packet->payload, 10) == 0) {
/* name is encoded as described in rfc883 */
u_int8_t name_length = packet->payload[12];
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"possible netbios positive name query response, one answer\n");
if (packet->payload_packet_len >= 12 + 1 + name_length + 1 + 2 + 2) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"possible netbios name query response, length matches\n");
/* null terminated? */
if (packet->payload[12 + name_length + 1] == 0 &&
get_u_int16_t(packet->payload, 12 + name_length + 2) == htons(0x0020) &&
get_u_int16_t(packet->payload, 12 + name_length + 4) == htons(0x0001)) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"found netbios name query response\n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
}
} else if (get_u_int16_t(packet->payload, 4) == 0 &&
get_u_int16_t(packet->payload, 6) == 0 &&
get_u_int16_t(packet->payload, 8) == 0 && get_u_int16_t(packet->payload, 10) == 0) {
/* name is encoded as described in rfc883 */
u_int8_t name_length = packet->payload[12];
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"possible netbios negative name query response, one answer\n");
if (packet->payload_packet_len >= 12 + 1 + name_length + 1 + 2 + 2) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"possible netbios name query response, length matches\n");
/* null terminated? */
if (packet->payload[12 + name_length + 1] == 0 &&
get_u_int16_t(packet->payload, 12 + name_length + 2) == htons(0x000A) &&
get_u_int16_t(packet->payload, 12 + name_length + 4) == htons(0x0001)) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"found netbios name query response\n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
}
} else if (get_u_int16_t(packet->payload, 4) == 0 &&
get_u_int16_t(packet->payload, 6) == 0 &&
get_u_int16_t(packet->payload, 8) == htons(1) && get_u_int16_t(packet->payload, 10) == htons(1)) {
/* name is encoded as described in rfc883 */
u_int8_t name_length = packet->payload[12];
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"possible netbios redirect name query response, one answer\n");
if (packet->payload_packet_len >= 12 + 1 + name_length + 1 + 2 + 2) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"possible netbios name query response, length matches\n");
/* null terminated? */
if (packet->payload[12 + name_length + 1] == 0 &&
get_u_int16_t(packet->payload, 12 + name_length + 2) == htons(0x0002) &&
get_u_int16_t(packet->payload, 12 + name_length + 4) == htons(0x0001)) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG,
"found netbios name query response\n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
}
}
}
/* TODO: extend according to rfc1002 */
}
/*check standard NETBIOS over udp to port 138 */
/*netbios header token from http://www.protocolbase.net/protocols/protocol_NBDGM.php */
if ((dport == 138) &&
packet->payload_packet_len >= 14 &&
ntohs(get_u_int16_t(packet->payload, 10)) == packet->payload_packet_len - 14) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG, "found netbios port 138 and payload length >= 112 \n");
if (packet->payload[0] >= 0x11 && packet->payload[0] <= 0x16) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG, "found netbios with MSG-type 0x11,0x12,0x13,0x14,0x15 or 0x16\n");
if (ntohl(get_u_int32_t(packet->payload, 4)) == ntohl(packet->iph->saddr)) {
char name[64];
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG, "found netbios with checked ip-address.\n");
if(netbios_name_interpret((char*)&packet->payload[12], name, sizeof(name)) > 0)
snprintf((char*)flow->host_server_name, sizeof(flow->host_server_name)-1, "%s", name);
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
}
}
}
if (packet->tcp != NULL) {
dport = ntohs(packet->tcp->dest);
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG, "netbios tcp start\n");
/* destination port must be 139 */
if (dport == 139) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG, "found netbios with destination port 139\n");
/* payload_packet_len must be 72 */
if (packet->payload_packet_len == 72) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG, "found netbios with payload_packen_len = 72. \n");
if (packet->payload[0] == 0x81 && packet->payload[1] == 0 && ntohs(get_u_int16_t(packet->payload, 2)) == 68) {
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct,
NDPI_LOG_DEBUG,
"found netbios with session request = 81, flags=0 and length od following bytes = 68. \n");
ndpi_int_netbios_add_connection(ndpi_struct, flow);
return;
}
}
}
}
NDPI_LOG(NDPI_PROTOCOL_NETBIOS, ndpi_struct, NDPI_LOG_DEBUG, "exclude netbios\n");
NDPI_ADD_PROTOCOL_TO_BITMASK(flow->excluded_protocol_bitmask, NDPI_PROTOCOL_NETBIOS);
}
void init_netbios_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id, NDPI_PROTOCOL_BITMASK *detection_bitmask)
{
ndpi_set_bitmask_protocol_detection("NETBIOS", ndpi_struct, detection_bitmask, *id,
NDPI_PROTOCOL_NETBIOS,
ndpi_search_netbios,
NDPI_SELECTION_BITMASK_PROTOCOL_TCP_OR_UDP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,
SAVE_DETECTION_BITMASK_AS_UNKNOWN,
ADD_TO_DETECTION_BITMASK);
*id += 1;
}
#endif