1 /* crypto/buffer/buffer.c */
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 "cryptlib.h"
61 #include <openssl/buffer.h>
62
63 /* LIMIT_BEFORE_EXPANSION is the maximum n such that (n+3)/3*4 < 2**31. That
64 * function is applied in several functions in this file and this limit ensures
65 * that the result fits in an int. */
66 #define LIMIT_BEFORE_EXPANSION 0x5ffffffc
67
68 BUF_MEM *BUF_MEM_new(void)
69 {
70 BUF_MEM *ret;
71
72 ret=OPENSSL_malloc(sizeof(BUF_MEM));
73 if (ret == NULL)
74 {
75 BUFerr(BUF_F_BUF_MEM_NEW,ERR_R_MALLOC_FAILURE);
76 return(NULL);
77 }
78 ret->length=0;
79 ret->max=0;
80 ret->data=NULL;
81 return(ret);
82 }
83
84 void BUF_MEM_free(BUF_MEM *a)
85 {
86 if(a == NULL)
87 return;
88
89 if (a->data != NULL)
90 {
91 memset(a->data,0,(unsigned int)a->max);
92 OPENSSL_free(a->data);
93 }
94 OPENSSL_free(a);
95 }
96
97 int BUF_MEM_grow(BUF_MEM *str, size_t len)
98 {
99 char *ret;
100 size_t n;
101
102 if (str->length >= len)
103 {
104 str->length=len;
105 return(len);
106 }
107 if (str->max >= len)
108 {
109 memset(&str->data[str->length],0,len-str->length);
110 str->length=len;
111 return(len);
112 }
113 /* This limit is sufficient to ensure (len+3)/3*4 < 2**31 */
114 if (len > LIMIT_BEFORE_EXPANSION)
115 {
116 BUFerr(BUF_F_BUF_MEM_GROW,ERR_R_MALLOC_FAILURE);
117 return 0;
118 }
119 n=(len+3)/3*4;
120 if (str->data == NULL)
121 ret=OPENSSL_malloc(n);
122 else
123 ret=OPENSSL_realloc(str->data,n);
124 if (ret == NULL)
125 {
126 BUFerr(BUF_F_BUF_MEM_GROW,ERR_R_MALLOC_FAILURE);
127 len=0;
128 }
129 else
130 {
131 str->data=ret;
132 str->max=n;
133 memset(&str->data[str->length],0,len-str->length);
134 str->length=len;
135 }
136 return(len);
137 }
138
139 int BUF_MEM_grow_clean(BUF_MEM *str, size_t len)
140 {
141 char *ret;
142 size_t n;
143
144 if (str->length >= len)
145 {
146 memset(&str->data[len],0,str->length-len);
147 str->length=len;
148 return(len);
149 }
150 if (str->max >= len)
151 {
152 memset(&str->data[str->length],0,len-str->length);
153 str->length=len;
154 return(len);
155 }
156 /* This limit is sufficient to ensure (len+3)/3*4 < 2**31 */
157 if (len > LIMIT_BEFORE_EXPANSION)
158 {
159 BUFerr(BUF_F_BUF_MEM_GROW_CLEAN,ERR_R_MALLOC_FAILURE);
160 return 0;
161 }
162 n=(len+3)/3*4;
163 if (str->data == NULL)
164 ret=OPENSSL_malloc(n);
165 else
166 ret=OPENSSL_realloc_clean(str->data,str->max,n);
167 if (ret == NULL)
168 {
169 BUFerr(BUF_F_BUF_MEM_GROW_CLEAN,ERR_R_MALLOC_FAILURE);
170 len=0;
171 }
172 else
173 {
174 str->data=ret;
175 str->max=n;
176 memset(&str->data[str->length],0,len-str->length);
177 str->length=len;
178 }
179 return(len);
180 }
181
182 void BUF_reverse(unsigned char *out, const unsigned char *in, size_t size)
183 {
184 size_t i;
185 if (in)
186 {
187 out += size - 1;
188 for (i = 0; i < size; i++)
189 *out-- = *in++;
190 }
191 else
192 {
193 unsigned char *q;
194 char c;
195 q = out + size - 1;
196 for (i = 0; i < size/2; i++)
197 {
198 c = *q;
199 *q-- = *out;
200 *out++ = c;
201 }
202 }
203 }