1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
/*
* ciscovpn.c
*
* Copyright (C) 2013-20 - ntop.org
*
* 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/>.
*
* Dissector developed by Remy Mudingay <mudingay@ill.fr>
*
*/
#include "ndpi_protocol_ids.h"
#define NDPI_CURRENT_PROTO NDPI_PROTOCOL_CISCOVPN
#include "ndpi_api.h"
/* ****************************************************************** */
static void ndpi_int_ciscovpn_add_connection(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow)
{
ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_CISCOVPN, NDPI_PROTOCOL_UNKNOWN);
}
/* ****************************************************************** */
void ndpi_search_ciscovpn(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow)
{
struct ndpi_packet_struct *packet = &flow->packet;
u_int16_t udport = 0, usport = 0;
u_int16_t tdport = 0, tsport = 0;
NDPI_LOG_DBG(ndpi_struct, "search CISCOVPN\n");
if(packet->tcp != NULL) {
tsport = ntohs(packet->tcp->source), tdport = ntohs(packet->tcp->dest);
NDPI_LOG_DBG2(ndpi_struct, "calculated CISCOVPN over tcp ports\n");
}
if(packet->udp != NULL) {
usport = ntohs(packet->udp->source), udport = ntohs(packet->udp->dest);
NDPI_LOG_DBG2(ndpi_struct, "calculated CISCOVPN over udp ports\n");
}
if((tdport == 10000 && tsport == 10000) ||
((tsport == 443 || tdport == 443) &&
(packet->payload_packet_len >= 4) &&
(packet->payload[0] == 0x17 /* TLS Application Data */ &&
packet->payload[1] == 0x01 &&
packet->payload[2] == 0x00 &&
packet->payload[3] == 0x00)
)
) {
/* This is a good query 17010000*/
NDPI_LOG_INFO(ndpi_struct, "found CISCOVPN\n");
ndpi_int_ciscovpn_add_connection(ndpi_struct, flow);
return;
}
#if 0
/* Code disabled as it is too generic and it can lead to false positives */
else if(((tsport == 443 || tdport == 443) ||
(tsport == 80 || tdport == 80)) &&
(packet->payload_packet_len >= 5) &&
((packet->payload[0] == 0x17 /* TLS Application Data */ &&
packet->payload[1] == 0x03 && packet->payload[2] == 0x03 && /* TLS 1.2 */
packet->payload[3] == 0x00 && packet->payload[4] == 0x3A /* Length */)))
{
/* TLS signature of Cisco AnyConnect 0X170303003A */
NDPI_LOG_INFO(ndpi_struct, "found CISCO Anyconnect VPN\n");
ndpi_int_ciscovpn_add_connection(ndpi_struct, flow);
return;
}
#endif
else if(((tsport == 8009 || tdport == 8009) ||
(tsport == 8008 || tdport == 8008)) &&
(packet->payload_packet_len >= 5) &&
((packet->payload[0] == 0x17 /* TLS Application Data */ &&
packet->payload[1] == 0x03 && packet->payload[2] == 0x03 && /* TLS 1.2 */
packet->payload[3] == 0x00 && packet->payload[4] == 0x69 /* Length */)))
{
/* TCP signature of Cisco AnyConnect 0X1703030069 */
NDPI_LOG_INFO(ndpi_struct, "found CISCO Anyconnect VPN\n");
ndpi_int_ciscovpn_add_connection(ndpi_struct, flow);
return;
}
else if(
(
(usport == 10000 && udport == 10000)
&&
(packet->payload_packet_len >= 4) &&
(packet->payload[0] == 0xfe &&
packet->payload[1] == 0x57 &&
packet->payload[2] == 0x7e &&
packet->payload[3] == 0x2b)
)
)
{
/* This is a good query fe577e2b */
NDPI_LOG_INFO(ndpi_struct, "found CISCOVPN\n");
ndpi_int_ciscovpn_add_connection(ndpi_struct, flow);
} else if(
(
(usport == 443 || udport == 443)
&&
(packet->payload_packet_len >= 5) &&
(packet->payload[0] == 0x17 /* TLS Application Data */ &&
packet->payload[1] == 0x01 &&
packet->payload[2] == 0x00 &&
packet->payload[3] == 0x00 &&
packet->payload[4] == 0x01)
)
)
{
NDPI_LOG_INFO(ndpi_struct, "found CISCOVPN\n");
ndpi_int_ciscovpn_add_connection(ndpi_struct, flow);
return;
}
if(flow->num_processed_pkts > 5)
NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
}
void init_ciscovpn_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id, NDPI_PROTOCOL_BITMASK *detection_bitmask)
{
ndpi_set_bitmask_protocol_detection("CiscoVPN", ndpi_struct, detection_bitmask, *id,
NDPI_PROTOCOL_CISCOVPN,
ndpi_search_ciscovpn,
NDPI_SELECTION_BITMASK_PROTOCOL_TCP_OR_UDP_WITH_PAYLOAD,
SAVE_DETECTION_BITMASK_AS_UNKNOWN,
ADD_TO_DETECTION_BITMASK);
*id += 1;
}
|