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
|
#include <machine/rtems-bsd-user-space.h>
#ifdef __rtems__
#include <machine/rtems-bsd-program.h>
#include "rtems-bsd-tcpdump-namespace.h"
#endif /* __rtems__ */
/*-
* Copyright (c) 2003, 2004 David Young. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of David Young may not be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID
* YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdlib.h>
#include <string.h>
#include <netdissect-stdinc.h>
#include "cpack.h"
#include "extract.h"
const uint8_t *
cpack_next_boundary(const uint8_t *buf, const uint8_t *p, size_t alignment)
{
size_t misalignment = (size_t)(p - buf) % alignment;
if (misalignment == 0)
return p;
return p + (alignment - misalignment);
}
/* Advance to the next wordsize boundary. Return NULL if fewer than
* wordsize bytes remain in the buffer after the boundary. Otherwise,
* return a pointer to the boundary.
*/
const uint8_t *
cpack_align_and_reserve(struct cpack_state *cs, size_t wordsize)
{
const uint8_t *next;
/* Ensure alignment. */
next = cpack_next_boundary(cs->c_buf, cs->c_next, wordsize);
/* Too little space for wordsize bytes? */
if (next - cs->c_buf + wordsize > cs->c_len)
return NULL;
return next;
}
/* Advance by N bytes without returning them. */
int
cpack_advance(struct cpack_state *cs, const size_t toskip)
{
/* No space left? */
if (cs->c_next - cs->c_buf + toskip > cs->c_len)
return -1;
cs->c_next += toskip;
return 0;
}
int
cpack_init(struct cpack_state *cs, const uint8_t *buf, size_t buflen)
{
memset(cs, 0, sizeof(*cs));
cs->c_buf = buf;
cs->c_len = buflen;
cs->c_next = cs->c_buf;
return 0;
}
/* Unpack a 64-bit unsigned integer. */
int
cpack_uint64(struct cpack_state *cs, uint64_t *u)
{
const uint8_t *next;
if ((next = cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
return -1;
*u = EXTRACT_LE_64BITS(next);
/* Move pointer past the uint64_t. */
cs->c_next = next + sizeof(*u);
return 0;
}
/* Unpack a 32-bit unsigned integer. */
int
cpack_uint32(struct cpack_state *cs, uint32_t *u)
{
const uint8_t *next;
if ((next = cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
return -1;
*u = EXTRACT_LE_32BITS(next);
/* Move pointer past the uint32_t. */
cs->c_next = next + sizeof(*u);
return 0;
}
/* Unpack a 16-bit unsigned integer. */
int
cpack_uint16(struct cpack_state *cs, uint16_t *u)
{
const uint8_t *next;
if ((next = cpack_align_and_reserve(cs, sizeof(*u))) == NULL)
return -1;
*u = EXTRACT_LE_16BITS(next);
/* Move pointer past the uint16_t. */
cs->c_next = next + sizeof(*u);
return 0;
}
/* Unpack an 8-bit unsigned integer. */
int
cpack_uint8(struct cpack_state *cs, uint8_t *u)
{
/* No space left? */
if ((size_t)(cs->c_next - cs->c_buf) >= cs->c_len)
return -1;
*u = *cs->c_next;
/* Move pointer past the uint8_t. */
cs->c_next++;
return 0;
}
#ifdef __rtems__
#include "rtems-bsd-tcpdump-cpack-data.h"
#endif /* __rtems__ */
|
