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
|
/* crc32-tvb.c
* CRC-32 tvbuff routines
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* SPDX-License-Identifier: GPL-2.0-or-later
*
* Credits:
*
* Table from Solomon Peachy
* Routine from Chris Waters
*/
#include "config.h"
#include <glib.h>
#include <epan/tvbuff.h>
#include <wsutil/crc32.h>
#include <epan/crc32-tvb.h>
uint32_t
crc32_ccitt_tvb(tvbuff_t *tvb, unsigned len)
{
const uint8_t* buf;
tvb_ensure_bytes_exist(tvb, 0, len); /* len == -1 not allowed */
buf = tvb_get_ptr(tvb, 0, len);
return ( crc32_ccitt_seed(buf, len, CRC32_CCITT_SEED) );
}
uint32_t
crc32_ccitt_tvb_offset(tvbuff_t *tvb, unsigned offset, unsigned len)
{
const uint8_t* buf;
tvb_ensure_bytes_exist(tvb, offset, len); /* len == -1 not allowed */
buf = tvb_get_ptr(tvb, offset, len);
return ( crc32_ccitt(buf, len) );
}
uint32_t
crc32_ccitt_tvb_seed(tvbuff_t *tvb, unsigned len, uint32_t seed)
{
const uint8_t* buf;
tvb_ensure_bytes_exist(tvb, 0, len); /* len == -1 not allowed */
buf = tvb_get_ptr(tvb, 0, len);
return ( crc32_ccitt_seed(buf, len, seed) );
}
uint32_t
crc32_ccitt_tvb_offset_seed(tvbuff_t *tvb, unsigned offset, unsigned len,
uint32_t seed)
{
const uint8_t* buf;
tvb_ensure_bytes_exist(tvb, offset, len); /* len == -1 not allowed */
buf = tvb_get_ptr(tvb, offset, len);
return ( crc32_ccitt_seed(buf, len, seed) );
}
uint32_t
crc32c_tvb_offset_calculate(tvbuff_t *tvb, unsigned offset, unsigned len, uint32_t seed)
{
const uint8_t* buf;
tvb_ensure_bytes_exist(tvb, offset, len); /* len == -1 not allowed */
buf = tvb_get_ptr(tvb, offset, len);
return ( crc32c_calculate(buf, len, seed) );
}
/*
* IEEE 802.x version (Ethernet and 802.11, at least) - byte-swap
* the result of "crc32()".
*
* XXX - does this mean we should fetch the Ethernet and 802.11
* FCS with "tvb_get_letohl()" rather than "tvb_get_ntohl()",
* or is fetching it big-endian and byte-swapping the CRC done
* to cope with 802.x sending stuff out in reverse bit order?
*/
uint32_t
crc32_802_tvb(tvbuff_t *tvb, unsigned len)
{
uint32_t c_crc;
c_crc = crc32_ccitt_tvb(tvb, len);
/* Byte reverse. */
c_crc = GUINT32_SWAP_LE_BE(c_crc);
return ( c_crc );
}
uint32_t
crc32_mpeg2_tvb_offset_seed(tvbuff_t *tvb, unsigned offset,
unsigned len, uint32_t seed)
{
const uint8_t* buf;
tvb_ensure_bytes_exist(tvb, offset, len); /* len == -1 not allowed */
buf = tvb_get_ptr(tvb, offset, len);
return ( crc32_mpeg2_seed(buf, len, seed) );
}
uint32_t
crc32_mpeg2_tvb(tvbuff_t *tvb, unsigned len)
{
return ( crc32_mpeg2_tvb_offset_seed(tvb, 0, len, CRC32_MPEG2_SEED) );
}
uint32_t
crc32_mpeg2_tvb_offset(tvbuff_t *tvb, unsigned offset, unsigned len)
{
return ( crc32_mpeg2_tvb_offset_seed(tvb, offset, len, CRC32_MPEG2_SEED) );
}
uint32_t
crc32_mpeg2_tvb_seed(tvbuff_t *tvb, unsigned len, uint32_t seed)
{
return ( crc32_mpeg2_tvb_offset_seed(tvb, 0, len, seed) );
}
uint32_t crc32_0x0AA725CF_tvb_offset_seed(tvbuff_t *tvb,
unsigned offset, unsigned len, uint32_t seed)
{
const uint8_t *buf;
tvb_ensure_bytes_exist(tvb, offset, len); /* len == -1 not allowed */
buf = tvb_get_ptr(tvb, offset, len);
return crc32_0x0AA725CF_seed(buf, len, seed);
}
/*
* 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:
*/
|
