1 /* $OpenBSD: buffer.c,v 1.27 2017/05/02 03:59:44 deraadt Exp $ */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62
63 #include <openssl/buffer.h>
64 #include <openssl/err.h>
65
66 /*
67 * LIMIT_BEFORE_EXPANSION is the maximum n such that (n + 3) / 3 * 4 < 2**31.
68 * That function is applied in several functions in this file and this limit
69 * ensures that the result fits in an int.
70 */
71 #define LIMIT_BEFORE_EXPANSION 0x5ffffffc
72
73 BUF_MEM *
BUF_MEM_new(void)74 BUF_MEM_new(void)
75 {
76 BUF_MEM *ret;
77
78 if ((ret = calloc(1, sizeof(BUF_MEM))) == NULL) {
79 BUFerror(ERR_R_MALLOC_FAILURE);
80 return (NULL);
81 }
82
83 return (ret);
84 }
85
86 void
BUF_MEM_free(BUF_MEM * a)87 BUF_MEM_free(BUF_MEM *a)
88 {
89 if (a == NULL)
90 return;
91
92 freezero(a->data, a->max);
93 free(a);
94 }
95
96 int
BUF_MEM_grow(BUF_MEM * str,size_t len)97 BUF_MEM_grow(BUF_MEM *str, size_t len)
98 {
99 return BUF_MEM_grow_clean(str, len);
100 }
101
102 int
BUF_MEM_grow_clean(BUF_MEM * str,size_t len)103 BUF_MEM_grow_clean(BUF_MEM *str, size_t len)
104 {
105 char *ret;
106 size_t n;
107
108 if (str->max >= len) {
109 if (str->length >= len)
110 memset(&str->data[len], 0, str->length - len);
111 str->length = len;
112 return (len);
113 }
114
115 if (len > LIMIT_BEFORE_EXPANSION) {
116 BUFerror(ERR_R_MALLOC_FAILURE);
117 return 0;
118 }
119
120 n = (len + 3) / 3 * 4;
121 if ((ret = recallocarray(str->data, str->max, n, 1)) == NULL) {
122 BUFerror(ERR_R_MALLOC_FAILURE);
123 return (0);
124 }
125 str->data = ret;
126 str->max = n;
127 str->length = len;
128
129 return (len);
130 }
131
132 void
BUF_reverse(unsigned char * out,const unsigned char * in,size_t size)133 BUF_reverse(unsigned char *out, const unsigned char *in, size_t size)
134 {
135 size_t i;
136
137 if (in) {
138 out += size - 1;
139 for (i = 0; i < size; i++)
140 *out-- = *in++;
141 } else {
142 unsigned char *q;
143 char c;
144 q = out + size - 1;
145 for (i = 0; i < size / 2; i++) {
146 c = *q;
147 *q-- = *out;
148 *out++ = c;
149 }
150 }
151 }
152