/*
* sip.c
*
* Copyright (C) 2009-2011 by ipoque GmbH
* Copyright (C) 2011-20 - 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_protocol_ids.h"
#define NDPI_CURRENT_PROTO NDPI_PROTOCOL_SIP
#include "ndpi_api.h"
static void ndpi_int_sip_add_connection(struct ndpi_detection_module_struct *ndpi_struct,
struct ndpi_flow_struct *flow,
u_int8_t due_to_correlation) {
ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_SIP, NDPI_PROTOCOL_UNKNOWN);
}
#if !defined(WIN32)
static inline
#elif defined(MINGW_GCC)
__mingw_forceinline static
#else
__forceinline static
#endif
void ndpi_search_sip_handshake(struct ndpi_detection_module_struct
*ndpi_struct, struct ndpi_flow_struct *flow)
{
struct ndpi_packet_struct *packet = &flow->packet;
const u_int8_t *packet_payload = packet->payload;
u_int32_t payload_len = packet->payload_packet_len;
if(payload_len > 4) {
/* search for STUN Turn ChannelData Prefix */
u_int16_t message_len = ntohs(get_u_int16_t(packet->payload, 2));
if(payload_len - 4 == message_len) {
NDPI_LOG_DBG2(ndpi_struct, "found STUN TURN ChannelData prefix\n");
payload_len -= 4;
packet_payload += 4;
}
}
if(payload_len >= 14) {
if((memcmp(packet_payload, "NOTIFY ", 7) == 0 || memcmp(packet_payload, "notify ", 7) == 0)
&& (memcmp(&packet_payload[7], "SIP:", 4) == 0 || memcmp(&packet_payload[7], "sip:", 4) == 0)) {
NDPI_LOG_INFO(ndpi_struct, "found sip NOTIFY\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
if((memcmp(packet_payload, "REGISTER ", 9) == 0 || memcmp(packet_payload, "register ", 9) == 0)
&& (memcmp(&packet_payload[9], "SIP:", 4) == 0 || memcmp(&packet_payload[9], "sip:", 4) == 0)) {
NDPI_LOG_INFO(ndpi_struct, "found sip REGISTER\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
if((memcmp(packet_payload, "INVITE ", 7) == 0 || memcmp(packet_payload, "invite ", 7) == 0)
&& (memcmp(&packet_payload[7], "SIP:", 4) == 0 || memcmp(&packet_payload[7], "sip:", 4) == 0)) {
NDPI_LOG_INFO(ndpi_struct, "found sip INVITE\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
/* seen this in second direction on the third position,
* maybe it could be deleted, if somebody sees it in the first direction,
* please delete this comment.
*/
/*
if(memcmp(packet_payload, "SIP/2.0 200 OK", 14) == 0 || memcmp(packet_payload, "sip/2.0 200 OK", 14) == 0) {
NDPI_LOG_INFO(ndpi_struct, "found sip SIP/2.0 0K\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
*/
if(memcmp(packet_payload, "SIP/2.0 ", 8) == 0 || memcmp(packet_payload, "sip/2.0 ", 8) == 0) {
NDPI_LOG_INFO(ndpi_struct, "found sip SIP/2.0 *\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
if((memcmp(packet_payload, "BYE ", 4) == 0 || memcmp(packet_payload, "bye ", 4) == 0)
&& (memcmp(&packet_payload[4], "SIP:", 4) == 0 || memcmp(&packet_payload[4], "sip:", 4) == 0)) {
NDPI_LOG_INFO(ndpi_struct, "found sip BYE\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
if((memcmp(packet_payload, "ACK ", 4) == 0 || memcmp(packet_payload, "ack ", 4) == 0)
&& (memcmp(&packet_payload[4], "SIP:", 4) == 0 || memcmp(&packet_payload[4], "sip:", 4) == 0)) {
NDPI_LOG_INFO(ndpi_struct, "found sip ACK\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
if((memcmp(packet_payload, "CANCEL ", 7) == 0 || memcmp(packet_payload, "cancel ", 7) == 0)
&& (memcmp(&packet_payload[7], "SIP:", 4) == 0 || memcmp(&packet_payload[7], "sip:", 4) == 0)) {
NDPI_LOG_INFO(ndpi_struct, "found sip CANCEL\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
if((memcmp(packet_payload, "PUBLISH ", 8) == 0 || memcmp(packet_payload, "publish ", 8) == 0)
&& (memcmp(&packet_payload[8], "SIP:", 4) == 0 || memcmp(&packet_payload[8], "sip:", 4) == 0)) {
NDPI_LOG_INFO(ndpi_struct, "found sip PUBLISH\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
if((memcmp(packet_payload, "SUBSCRIBE ", 10) == 0 || memcmp(packet_payload, "subscribe ", 10) == 0)
&& (memcmp(&packet_payload[10], "SIP:", 4) == 0 || memcmp(&packet_payload[10], "sip:", 4) == 0)) {
NDPI_LOG_INFO(ndpi_struct, "found sip SUBSCRIBE\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
/* SIP message extension RFC 3248 */
if((memcmp(packet_payload, "MESSAGE ", 8) == 0 || memcmp(packet_payload, "message ", 8) == 0)
&& (memcmp(&packet_payload[8], "SIP:", 4) == 0 || memcmp(&packet_payload[8], "sip:", 4) == 0)) {
NDPI_LOG_INFO(ndpi_struct, "found sip MESSAGE\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
/* Courtesy of Miguel Quesada <mquesadab@gmail.com> */
if((memcmp(packet_payload, "OPTIONS ", 8) == 0
|| memcmp(packet_payload, "options ", 8) == 0)
&& (memcmp(&packet_payload[8], "SIP:", 4) == 0
|| memcmp(&packet_payload[8], "sip:", 4) == 0)) {
NDPI_LOG_INFO(ndpi_struct, "found sip OPTIONS\n");
ndpi_int_sip_add_connection(ndpi_struct, flow, 0);
return;
}
}
/* add bitmask for tcp only, some stupid udp programs
* send a very few (< 10 ) packets before invite (mostly a 0x0a0x0d, but just search the first 3 payload_packets here */
if(packet->udp != NULL && flow->packet_counter < 20) {
NDPI_LOG_DBG2(ndpi_struct, "need next packet\n");
return;
}
/* for STUN flows we need some more packets */
if(packet->udp != NULL && flow->detected_protocol_stack[0] == NDPI_PROTOCOL_STUN && flow->packet_counter < 40) {
NDPI_LOG_DBG2(ndpi_struct, "need next STUN packet\n");
return;
}
if(payload_len == 4 && get_u_int32_t(packet_payload, 0) == 0) {
NDPI_LOG_DBG2(ndpi_struct, "maybe sip. need next packet\n");
return;
}
NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
}
void ndpi_search_sip(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow)
{
struct ndpi_packet_struct *packet = &flow->packet;
NDPI_LOG_DBG(ndpi_struct, "search sip\n");
if(flow->packet_counter > 5)
NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
else {
/* skip marked packets */
if(packet->detected_protocol_stack[0] != NDPI_PROTOCOL_SIP) {
if(packet->tcp_retransmission == 0) {
ndpi_search_sip_handshake(ndpi_struct, flow);
}
}
}
}
void init_sip_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id, NDPI_PROTOCOL_BITMASK *detection_bitmask)
{
ndpi_set_bitmask_protocol_detection("SIP", ndpi_struct, detection_bitmask, *id,
NDPI_PROTOCOL_SIP,
ndpi_search_sip,
NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_OR_UDP_WITH_PAYLOAD,/* Fix courtesy of Miguel Quesada <mquesadab@gmail.com> */
SAVE_DETECTION_BITMASK_AS_UNKNOWN,
ADD_TO_DETECTION_BITMASK);
*id += 1;
}