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
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
/*
* quic.c
*
* Copyright (C) 2012-20 - ntop.org
*
* This module 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.
*
* This module 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.
* If not, see <http://www.gnu.org/licenses/>.
*
* Based on code of:
* Andrea Buscarinu - <andrea.buscarinu@gmail.com>
* Michele Campus - <campus@ntop.org>
*
*/
#if defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__
#include <sys/endian.h>
#endif
#include "ndpi_protocol_ids.h"
#define NDPI_CURRENT_PROTO NDPI_PROTOCOL_QUIC
#include "ndpi_api.h"
static int quic_ports(u_int16_t sport, u_int16_t dport)
{
if ((sport == 443 || dport == 443 || sport == 80 || dport == 80) &&
(sport != 123 && dport != 123))
return 1;
return 0;
}
/* ***************************************************************** */
static int quic_len(u_int8_t l) {
switch(l) {
case 0:
return(1);
break;
case 1:
return(2);
break;
case 2:
return(4);
break;
case 3:
return(8);
break;
}
return(0); /* NOTREACHED */
}
/* ***************************************************************** */
void ndpi_search_quic(struct ndpi_detection_module_struct *ndpi_struct,
struct ndpi_flow_struct *flow)
{
struct ndpi_packet_struct *packet = &flow->packet;
u_int32_t udp_len = packet->payload_packet_len;
u_int version_len = ((packet->payload[0] & 0x01) == 0) ? 0 : 4;
u_int cid_len = quic_len((packet->payload[0] & 0x0C) >> 2);
u_int seq_len = quic_len((packet->payload[0] & 0x30) >> 4);
u_int quic_hlen = 1 /* flags */ + version_len + seq_len + cid_len;
NDPI_LOG_DBG(ndpi_struct, "search QUIC\n");
if(packet->udp != NULL
&& (udp_len > (quic_hlen+4 /* QXXX */))
// && ((packet->payload[0] & 0xC2) == 0x00)
&& (quic_ports(ntohs(packet->udp->source), ntohs(packet->udp->dest)))
) {
int i;
if((packet->payload[1] == 'Q')
&& (packet->payload[2] == '0')
&& (packet->payload[3] == '4')
&& (packet->payload[4] == '6')
&& (version_len == 1)
)
quic_hlen = 18; /* TODO: Better handle Q046 */
else {
u_int16_t potential_stun_len = ntohs((*((u_int16_t*)&packet->payload[2])));
if((version_len > 0) && (packet->payload[1+cid_len] != 'Q'))
goto no_quic;
if((version_len == 0) && ((packet->payload[0] & 0xC3 /* ignore CID len/packet number */) != 0))
goto no_quic;
/* Heuristic to see if this packet could be a STUN packet */
if((potential_stun_len /* STUN message len */ < udp_len)
&& ((potential_stun_len+25 /* Attribute header overhead we assume is max */) /* STUN message len */ > udp_len))
return; /* This could be STUN, let's skip this packet */
NDPI_LOG_INFO(ndpi_struct, "found QUIC\n");
ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_QUIC, NDPI_PROTOCOL_UNKNOWN);
if(packet->payload[quic_hlen+12] != 0xA0)
quic_hlen++;
}
if(udp_len > quic_hlen + 16 + 4) {
if(!strncmp((char*)&packet->payload[quic_hlen+16], "CHLO" /* Client Hello */, 4)) {
/* Check if SNI (Server Name Identification) is present */
for(i=quic_hlen+12; i<udp_len-3; i++) {
if((packet->payload[i] == 'S')
&& (packet->payload[i+1] == 'N')
&& (packet->payload[i+2] == 'I')
&& (packet->payload[i+3] == 0)) {
u_int32_t offset = (*((u_int32_t*)&packet->payload[i+4]));
u_int32_t prev_offset = (*((u_int32_t*)&packet->payload[i-4]));
int len = offset-prev_offset;
int sni_offset = i+prev_offset+1;
while((sni_offset < udp_len) && (packet->payload[sni_offset] == '-'))
sni_offset++;
if((sni_offset+len) < udp_len) {
int max_len = sizeof(flow->host_server_name)-1, j = 0;
ndpi_protocol_match_result ret_match;
if(len > max_len) len = max_len;
while((len > 0) && (sni_offset < udp_len)) {
flow->host_server_name[j++] = packet->payload[sni_offset];
sni_offset++, len--;
}
ndpi_match_host_subprotocol(ndpi_struct, flow,
(char *)flow->host_server_name,
strlen((const char*)flow->host_server_name),
&ret_match,
NDPI_PROTOCOL_QUIC);
}
break;
}
}
}
}
return;
}
no_quic:
NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
}
/* ***************************************************************** */
void init_quic_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id,
NDPI_PROTOCOL_BITMASK *detection_bitmask)
{
ndpi_set_bitmask_protocol_detection("QUIC", ndpi_struct, detection_bitmask, *id,
NDPI_PROTOCOL_QUIC, ndpi_search_quic,
NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_UDP_WITH_PAYLOAD,
SAVE_DETECTION_BITMASK_AS_UNKNOWN, ADD_TO_DETECTION_BITMASK);
*id += 1;
}
|