1 /*
2  * vhua.c
3  *
4  * Copyright (C) 2011-21 - ntop.org
5  *
6  * nDPI is free software: you can vhuatribute it and/or modify
7  * it under the terms of the GNU Lesser General Public License as published by
8  * the Free Software Foundation, either version 3 of the License, or
9  * (at your option) any later version.
10  *
11  * nDPI is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public License
17  * along with nDPI.  If not, see <http://www.gnu.org/licenses/>.
18  *
19  */
20 #include "ndpi_protocol_ids.h"
21 
22 #define NDPI_CURRENT_PROTO NDPI_PROTOCOL_VHUA
23 
24 #include "ndpi_api.h"
25 
26 /*
27   http://www.vhua.com
28 
29   Skype-like Chinese phone protocol
30 
31  */
32 
33 
ndpi_int_vhua_add_connection(struct ndpi_detection_module_struct * ndpi_struct,struct ndpi_flow_struct * flow)34 static void ndpi_int_vhua_add_connection(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow) {
35   ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_VHUA, NDPI_PROTOCOL_UNKNOWN);
36   NDPI_LOG_INFO(ndpi_struct, "found VHUA\n");
37 }
38 
39 
ndpi_check_vhua(struct ndpi_detection_module_struct * ndpi_struct,struct ndpi_flow_struct * flow)40 static void ndpi_check_vhua(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow) {
41   struct ndpi_packet_struct *packet = &flow->packet;
42   u_int32_t payload_len = packet->payload_packet_len;
43   u_char p0[] =  { 0x05, 0x14, 0x3a, 0x05, 0x08, 0xf8, 0xa1, 0xb1, 0x03 };
44 
45   if(payload_len == 0) return; /* Shouldn't happen */
46 
47   /* Break after 3 packets. */
48   if((flow->packet_counter > 3)
49      || (packet->udp == NULL)
50      || (packet->payload_packet_len < sizeof(p0))) {
51     NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
52   } else if(memcmp(packet->payload, p0, sizeof(p0)) == 0) {
53     ndpi_int_vhua_add_connection(ndpi_struct, flow);
54   }
55 }
56 
ndpi_search_vhua(struct ndpi_detection_module_struct * ndpi_struct,struct ndpi_flow_struct * flow)57 void ndpi_search_vhua(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow) {
58   struct ndpi_packet_struct *packet = &flow->packet;
59 
60   NDPI_LOG_DBG(ndpi_struct, "search VHUA\n");
61 
62   /* skip marked packets */
63   if(packet->detected_protocol_stack[0] != NDPI_PROTOCOL_VHUA) {
64     ndpi_check_vhua(ndpi_struct, flow);
65   }
66 }
67 
68 
init_vhua_dissector(struct ndpi_detection_module_struct * ndpi_struct,u_int32_t * id,NDPI_PROTOCOL_BITMASK * detection_bitmask)69 void init_vhua_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id, NDPI_PROTOCOL_BITMASK *detection_bitmask)
70 {
71   ndpi_set_bitmask_protocol_detection("VHUA", ndpi_struct, detection_bitmask, *id,
72 				      NDPI_PROTOCOL_VHUA,
73 				      ndpi_search_vhua,
74 				      NDPI_SELECTION_BITMASK_PROTOCOL_UDP_WITH_PAYLOAD,
75 				      SAVE_DETECTION_BITMASK_AS_UNKNOWN,
76 				      ADD_TO_DETECTION_BITMASK);
77   *id += 1;
78 }
79 
80