2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
11 #include "internal/cryptlib.h"
12 #include <openssl/buffer.h>
15 * LIMIT_BEFORE_EXPANSION is the maximum n such that (n+3)/3*4 < 2**31. That
16 * function is applied in several functions in this file and this limit
17 * ensures that the result fits in an int.
19 #define LIMIT_BEFORE_EXPANSION 0x5ffffffc
21 BUF_MEM *BUF_MEM_new_ex(unsigned long flags)
31 BUF_MEM *BUF_MEM_new(void)
35 ret = OPENSSL_zalloc(sizeof(*ret));
37 BUFerr(BUF_F_BUF_MEM_NEW, ERR_R_MALLOC_FAILURE);
43 void BUF_MEM_free(BUF_MEM *a)
48 if (a->data != NULL) {
49 if (a->flags & BUF_MEM_FLAG_SECURE)
50 OPENSSL_secure_free(a->data);
52 OPENSSL_clear_free(a->data, a->max);
57 /* Allocate a block of secure memory; copy over old data if there
58 * was any, and then free it. */
59 static char *sec_alloc_realloc(BUF_MEM *str, size_t len)
63 ret = OPENSSL_secure_malloc(len);
64 if (str->data != NULL) {
66 memcpy(ret, str->data, str->length);
67 OPENSSL_secure_free(str->data);
72 size_t BUF_MEM_grow(BUF_MEM *str, size_t len)
77 if (str->length >= len) {
81 if (str->max >= len) {
82 if (str->data != NULL)
83 memset(&str->data[str->length], 0, len - str->length);
87 /* This limit is sufficient to ensure (len+3)/3*4 < 2**31 */
88 if (len > LIMIT_BEFORE_EXPANSION) {
89 BUFerr(BUF_F_BUF_MEM_GROW, ERR_R_MALLOC_FAILURE);
92 n = (len + 3) / 3 * 4;
93 if ((str->flags & BUF_MEM_FLAG_SECURE))
94 ret = sec_alloc_realloc(str, n);
96 ret = OPENSSL_realloc(str->data, n);
98 BUFerr(BUF_F_BUF_MEM_GROW, ERR_R_MALLOC_FAILURE);
103 memset(&str->data[str->length], 0, len - str->length);
109 size_t BUF_MEM_grow_clean(BUF_MEM *str, size_t len)
114 if (str->length >= len) {
115 if (str->data != NULL)
116 memset(&str->data[len], 0, str->length - len);
120 if (str->max >= len) {
121 memset(&str->data[str->length], 0, len - str->length);
125 /* This limit is sufficient to ensure (len+3)/3*4 < 2**31 */
126 if (len > LIMIT_BEFORE_EXPANSION) {
127 BUFerr(BUF_F_BUF_MEM_GROW_CLEAN, ERR_R_MALLOC_FAILURE);
130 n = (len + 3) / 3 * 4;
131 if ((str->flags & BUF_MEM_FLAG_SECURE))
132 ret = sec_alloc_realloc(str, n);
134 ret = OPENSSL_clear_realloc(str->data, str->max, n);
136 BUFerr(BUF_F_BUF_MEM_GROW_CLEAN, ERR_R_MALLOC_FAILURE);
141 memset(&str->data[str->length], 0, len - str->length);
147 void BUF_reverse(unsigned char *out, const unsigned char *in, size_t size)
152 for (i = 0; i < size; i++)
158 for (i = 0; i < size / 2; i++) {