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
|
/*
Unix SMB/Netbios implementation.
Version 3.0
simple SPNEGO routines
Copyright (C) Andrew Tridgell 2001
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "includes.h"
/* free an asn1 structure */
void asn1_free(ASN1_DATA *data)
{
SAFE_FREE(data->data);
}
/* write to the ASN1 buffer, advancing the buffer pointer */
BOOL asn1_write(ASN1_DATA *data, const void *p, int len)
{
if (data->length < data->ofs+len) {
data->data = Realloc(data->data, data->ofs+len);
if (!data->data) return False;
data->length = data->ofs+len;
}
memcpy(data->data + data->ofs, p, len);
data->ofs += len;
return True;
}
/* useful fn for writing a uint8 */
BOOL asn1_write_uint8(ASN1_DATA *data, uint8 v)
{
return asn1_write(data, &v, 1);
}
/* push a tag onto the asn1 data buffer. Used for nested structures */
BOOL asn1_push_tag(ASN1_DATA *data, uint8 tag)
{
struct nesting *nesting;
asn1_write_uint8(data, tag);
nesting = (struct nesting *)malloc(sizeof(struct nesting));
if (!nesting) return False;
nesting->start = data->ofs;
nesting->next = data->nesting;
data->nesting = nesting;
asn1_write_uint8(data, 0xff);
return True;
}
/* pop a tag */
BOOL asn1_pop_tag(ASN1_DATA *data)
{
struct nesting *nesting;
size_t len;
nesting = data->nesting;
if (!nesting) {
return False;
}
len = data->ofs - (nesting->start+1);
/* yes, this is ugly. We don't know in advance how many bytes the length
of a tag will take, so we assumed 1 byte. If we were wrong then we
need to correct our mistake */
if (len > 127) {
data->data[nesting->start] = 0x82;
asn1_write_uint8(data, 0);
asn1_write_uint8(data, 0);
memmove(data->data+nesting->start+3, data->data+nesting->start+1, len);
data->data[nesting->start+1] = len>>8;
data->data[nesting->start+2] = len&0xff;
} else {
data->data[nesting->start] = len;
}
data->nesting = nesting->next;
free(nesting);
return True;
}
/* write an object ID to a ASN1 buffer */
BOOL asn1_write_OID(ASN1_DATA *data, const char *OID)
{
unsigned v, v2;
char *p = (char *)OID;
asn1_push_tag(data, ASN1_OID);
v = strtol(p, &p, 10);
v2 = strtol(p, &p, 10);
asn1_write_uint8(data, 40*v + v2);
while (*p) {
v = strtol(p, &p, 10);
if (v >= (1<<28)) asn1_write_uint8(data, 0x80 | ((v>>28)&0xff));
if (v >= (1<<21)) asn1_write_uint8(data, 0x80 | ((v>>21)&0xff));
if (v >= (1<<14)) asn1_write_uint8(data, 0x80 | ((v>>14)&0xff));
if (v >= (1<<7)) asn1_write_uint8(data, 0x80 | ((v>>7)&0xff));
asn1_write_uint8(data, v&0x7f);
}
asn1_pop_tag(data);
return True;
}
/* write an octet string */
BOOL asn1_write_OctetString(ASN1_DATA *data, const void *p, size_t length)
{
asn1_push_tag(data, ASN1_OCTET_STRING);
asn1_write(data, p, length);
asn1_pop_tag(data);
return True;
}
/* write a general string */
BOOL asn1_write_GeneralString(ASN1_DATA *data, const char *s)
{
asn1_push_tag(data, ASN1_GENERAL_STRING);
asn1_write(data, s, strlen(s));
asn1_pop_tag(data);
return True;
}
/* write a BOOLEAN */
BOOL asn1_write_BOOLEAN(ASN1_DATA *data, BOOL v)
{
asn1_write_uint8(data, ASN1_BOOLEAN);
asn1_write_uint8(data, v);
return True;
}
/* load a ASN1_DATA structure with a lump of data, ready to be parsed */
BOOL asn1_load(ASN1_DATA *data, void *p, size_t length)
{
ZERO_STRUCTP(data);
data->data = memdup(p, length);
if (!data->data) return False;
data->length = length;
return True;
}
/* read from a ASN1 buffer, advancing the buffer pointer */
BOOL asn1_read(ASN1_DATA *data, void *p, int len)
{
if (data->ofs + len > data->length) {
return False;
}
memcpy(p, data->data + data->ofs, len);
data->ofs += len;
return True;
}
|
