summaryrefslogtreecommitdiff
path: root/lib/util/data_blob.c
blob: 57b34b7ae73d8aa698dc9df4fc164dc22a8b4512 (plain)
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
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
/* 
   Unix SMB/CIFS implementation.
   Easy management of byte-length data
   Copyright (C) Andrew Tridgell 2001
   Copyright (C) Andrew Bartlett 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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"

/**
 * @file
 * @brief Manipulation of arbitrary data blobs
 **/

/**
 construct a data blob, must be freed with data_blob_free()
 you can pass NULL for p and get a blank data blob
**/
_PUBLIC_ DATA_BLOB data_blob_named(const void *p, size_t length, const char *name)
{
	DATA_BLOB ret;

	if (p == NULL && length == 0) {
		ZERO_STRUCT(ret);
		return ret;
	}

	if (p) {
		ret.data = (uint8_t *)talloc_memdup(NULL, p, length);
	} else {
		ret.data = talloc_array(NULL, uint8_t, length);
	}
	if (ret.data == NULL) {
		ret.length = 0;
		return ret;
	}
	talloc_set_name_const(ret.data, name);
	ret.length = length;
	return ret;
}

/**
 construct a data blob, using supplied TALLOC_CTX
**/
_PUBLIC_ DATA_BLOB data_blob_talloc_named(TALLOC_CTX *mem_ctx, const void *p, size_t length, const char *name)
{
	DATA_BLOB ret = data_blob_named(p, length, name);

	if (ret.data) {
		talloc_steal(mem_ctx, ret.data);
	}
	return ret;
}


/**
 reference a data blob, to the supplied TALLOC_CTX.  
 Returns a NULL DATA_BLOB on failure
**/
_PUBLIC_ DATA_BLOB data_blob_talloc_reference(TALLOC_CTX *mem_ctx, DATA_BLOB *blob)
{
	DATA_BLOB ret = *blob;

	ret.data = talloc_reference(mem_ctx, blob->data);

	if (!ret.data) {
		return data_blob(NULL, 0);
	}
	return ret;
}

/**
 construct a zero data blob, using supplied TALLOC_CTX. 
 use this sparingly as it initialises data - better to initialise
 yourself if you want specific data in the blob
**/
_PUBLIC_ DATA_BLOB data_blob_talloc_zero(TALLOC_CTX *mem_ctx, size_t length)
{
	DATA_BLOB blob = data_blob_talloc(mem_ctx, NULL, length);
	data_blob_clear(&blob);
	return blob;
}

/**
free a data blob
**/
_PUBLIC_ void data_blob_free(DATA_BLOB *d)
{
	if (d) {
		talloc_free(d->data);
		d->data = NULL;
		d->length = 0;
	}
}

/**
clear a DATA_BLOB's contents
**/
_PUBLIC_ void data_blob_clear(DATA_BLOB *d)
{
	if (d->data) {
		memset(d->data, 0, d->length);
	}
}

/**
free a data blob and clear its contents
**/
_PUBLIC_ void data_blob_clear_free(DATA_BLOB *d)
{
	data_blob_clear(d);
	data_blob_free(d);
}


/**
check if two data blobs are equal
**/
_PUBLIC_ int data_blob_cmp(const DATA_BLOB *d1, const DATA_BLOB *d2)
{
	int ret;
	if (d1->data == NULL && d2->data != NULL) {
		return -1;
	}
	if (d1->data != NULL && d2->data == NULL) {
		return 1;
	}
	if (d1->data == d2->data) {
		return d1->length - d2->length;
	}
	ret = memcmp(d1->data, d2->data, MIN(d1->length, d2->length));
	if (ret == 0) {
		return d1->length - d2->length;
	}
	return ret;
}

/**
print the data_blob as hex string
**/
_PUBLIC_ char *data_blob_hex_string(TALLOC_CTX *mem_ctx, const DATA_BLOB *blob)
{
	int i;
	char *hex_string;

	hex_string = talloc_array(mem_ctx, char, (blob->length*2)+1);
	if (!hex_string) {
		return NULL;
	}

	for (i = 0; i < blob->length; i++)
		slprintf(&hex_string[i*2], 3, "%02X", blob->data[i]);

	hex_string[(blob->length*2)] = '\0';
	return hex_string;
}

/**
  useful for constructing data blobs in test suites, while
  avoiding const warnings
**/
_PUBLIC_ DATA_BLOB data_blob_string_const(const char *str)
{
	DATA_BLOB blob;
	blob.data = discard_const_p(uint8_t, str);
	blob.length = str ? strlen(str) : 0;
	return blob;
}

/**
 * Create a new data blob from const data 
 */

_PUBLIC_ DATA_BLOB data_blob_const(const void *p, size_t length)
{
	DATA_BLOB blob;
	blob.data = discard_const_p(uint8_t, p);
	blob.length = length;
	return blob;
}


/**
  realloc a data_blob
**/
_PUBLIC_ bool data_blob_realloc(TALLOC_CTX *mem_ctx, DATA_BLOB *blob, size_t length)
{
	blob->data = talloc_realloc(mem_ctx, blob->data, uint8_t, length);
	if (blob->data == NULL)
		return false;
	blob->length = length;
	return true;
}


/**
  append some data to a data blob
**/
_PUBLIC_ bool data_blob_append(TALLOC_CTX *mem_ctx, DATA_BLOB *blob,
				   const void *p, size_t length)
{
	size_t old_len = blob->length;
	size_t new_len = old_len + length;
	if (new_len < length || new_len < old_len) {
		return false;
	}

	if ((const uint8_t *)p + length < (const uint8_t *)p) {
		return false;
	}
	
	if (!data_blob_realloc(mem_ctx, blob, new_len)) {
		return false;
	}

	memcpy(blob->data + old_len, p, length);
	return true;
}