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
|
/* atm.c
*
* Wiretap Library
* Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
#include "atm.h"
#include "wtap-int.h"
/*
* Routines to use with ATM capture file types that don't include information
* about the *type* of ATM traffic (or, at least, where we haven't found
* that information).
*
* We assume the traffic is AAL5, unless it's VPI 0/VCI 5, in which case
* we assume it's the signalling AAL.
*/
void
atm_guess_traffic_type(wtap_rec *rec)
{
/*
* Start out assuming nothing other than that it's AAL5.
*/
rec->rec_header.packet_header.pseudo_header.atm.aal = AAL_5;
rec->rec_header.packet_header.pseudo_header.atm.type = TRAF_UNKNOWN;
rec->rec_header.packet_header.pseudo_header.atm.subtype = TRAF_ST_UNKNOWN;
if (rec->rec_header.packet_header.pseudo_header.atm.vpi == 0) {
/*
* Traffic on some PVCs with a VPI of 0 and certain
* VCIs is of particular types.
*/
switch (rec->rec_header.packet_header.pseudo_header.atm.vci) {
case 5:
/*
* Signalling AAL.
*/
rec->rec_header.packet_header.pseudo_header.atm.aal = AAL_SIGNALLING;
return;
case 16:
/*
* ILMI.
*/
rec->rec_header.packet_header.pseudo_header.atm.type = TRAF_ILMI;
return;
}
}
/*
* OK, we can't tell what it is based on the VPI/VCI; try
* guessing based on the contents, if we have enough data
* to guess.
*/
if (rec->rec_header.packet_header.caplen >= 3) {
const uint8_t *pd = ws_buffer_start_ptr(&rec->data);
if (pd[0] == 0xaa && pd[1] == 0xaa && pd[2] == 0x03) {
/*
* Looks like a SNAP header; assume it's LLC
* multiplexed RFC 1483 traffic.
*/
rec->rec_header.packet_header.pseudo_header.atm.type = TRAF_LLCMX;
} else if ((rec->rec_header.packet_header.pseudo_header.atm.aal5t_len && rec->rec_header.packet_header.pseudo_header.atm.aal5t_len < 16) ||
rec->rec_header.packet_header.caplen < 16) {
/*
* As this cannot be a LANE Ethernet frame (less
* than 2 bytes of LANE header + 14 bytes of
* Ethernet header) we can try it as a SSCOP frame.
*/
rec->rec_header.packet_header.pseudo_header.atm.aal = AAL_SIGNALLING;
} else if (pd[0] == 0x83 || pd[0] == 0x81) {
/*
* MTP3b headers often encapsulate
* a SCCP or MTN in the 3G network.
* This should cause 0x83 or 0x81
* in the first byte.
*/
rec->rec_header.packet_header.pseudo_header.atm.aal = AAL_SIGNALLING;
} else {
/*
* Assume it's LANE.
*/
rec->rec_header.packet_header.pseudo_header.atm.type = TRAF_LANE;
atm_guess_lane_type(rec);
}
} else {
/*
* Not only VCI 5 is used for signaling. It might be
* one of these VCIs.
*/
rec->rec_header.packet_header.pseudo_header.atm.aal = AAL_SIGNALLING;
}
}
void
atm_guess_lane_type(wtap_rec *rec)
{
const uint8_t *pd = ws_buffer_start_ptr(&rec->data);
if (rec->rec_header.packet_header.caplen >= 2) {
if (pd[0] == 0xff && pd[1] == 0x00) {
/*
* Looks like LE Control traffic.
*/
rec->rec_header.packet_header.pseudo_header.atm.subtype = TRAF_ST_LANE_LE_CTRL;
} else {
/*
* XXX - Ethernet, or Token Ring?
* Assume Ethernet for now; if we see earlier
* LANE traffic, we may be able to figure out
* the traffic type from that, but there may
* still be situations where the user has to
* tell us.
*/
rec->rec_header.packet_header.pseudo_header.atm.subtype = TRAF_ST_LANE_802_3;
}
}
}
/*
* Editor modelines - https://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 8
* tab-width: 8
* indent-tabs-mode: t
* End:
*
* vi: set shiftwidth=8 tabstop=8 noexpandtab:
* :indentSize=8:tabSize=8:noTabs=false:
*/
|
