crypto/mem.c

   1 /*
   2  * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   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
   8  */
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <limits.h>
  13 #include <openssl/crypto.h>
  14 #include "internal/cryptlib.h"
  15
  16 /*
  17  * the following pointers may be changed as long as 'allow_customize' is set
  18  */
  19 static int allow_customize = 1;
  20
  21 static void *(*malloc_impl)(size_t, const char *, int)
  22     = CRYPTO_malloc;
  23 static void *(*realloc_impl)(void *, size_t, const char *, int)
  24     = CRYPTO_realloc;
  25 static void (*free_impl)(void *, const char *, int)
  26     = CRYPTO_free;
  27
  28 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
  29 static int call_malloc_debug = 1;
  30 #else
  31 static int call_malloc_debug = 0;
  32 #endif
  33
  34 int CRYPTO_set_mem_functions(
  35         void *(*m)(size_t, const char *, int),
  36         void *(*r)(void *, size_t, const char *, int),
  37         void (*f)(void *, const char *, int))
  38 {
  39     if (!allow_customize)
  40         return 0;
  41     if (m)
  42         malloc_impl = m;
  43     if (r)
  44         realloc_impl = r;
  45     if (f)
  46         free_impl = f;
  47     return 1;
  48 }
  49
  50 int CRYPTO_set_mem_debug(int flag)
  51 {
  52     if (!allow_customize)
  53         return 0;
  54     call_malloc_debug = flag;
  55     return 1;
  56 }
  57
  58 void CRYPTO_get_mem_functions(
  59         void *(**m)(size_t, const char *, int),
  60         void *(**r)(void *, size_t, const char *, int),
  61         void (**f)(void *, const char *, int))
  62 {
  63     if (m != NULL)
  64         *m = malloc_impl;
  65     if (r != NULL)
  66         *r = realloc_impl;
  67     if (f != NULL)
  68         *f = free_impl;
  69 }
  70
  71 void *CRYPTO_malloc(size_t num, const char *file, int line)
  72 {
  73     void *ret = NULL;
  74
  75     if (malloc_impl != NULL && malloc_impl != CRYPTO_malloc)
  76         return malloc_impl(num, file, line);
  77
  78     if (num <= 0)
  79         return NULL;
  80
  81     allow_customize = 0;
  82 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
  83     if (call_malloc_debug) {
  84         CRYPTO_mem_debug_malloc(NULL, num, 0, file, line);
  85         ret = malloc(num);
  86         CRYPTO_mem_debug_malloc(ret, num, 1, file, line);
  87     } else {
  88         ret = malloc(num);
  89     }
  90 #else
  91     osslargused(file); osslargused(line);
  92     ret = malloc(num);
  93 #endif
  94
  95     return ret;
  96 }
  97
  98 void *CRYPTO_zalloc(size_t num, const char *file, int line)
  99 {
 100     void *ret = CRYPTO_malloc(num, file, line);
 101
 102     if (ret != NULL)
 103         memset(ret, 0, num);
 104     return ret;
 105 }
 106
 107 void *CRYPTO_realloc(void *str, size_t num, const char *file, int line)
 108 {
 109     if (realloc_impl != NULL && realloc_impl != &CRYPTO_realloc)
 110         return realloc_impl(str, num, file, line);
 111
 112     if (str == NULL)
 113         return CRYPTO_malloc(num, file, line);
 114
 115     if (num == 0) {
 116         CRYPTO_free(str, file, line);
 117         return NULL;
 118     }
 119
 120     allow_customize = 0;
 121 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
 122     if (call_malloc_debug) {
 123         void *ret;
 124         CRYPTO_mem_debug_realloc(str, NULL, num, 0, file, line);
 125         ret = realloc(str, num);
 126         CRYPTO_mem_debug_realloc(str, ret, num, 1, file, line);
 127         return ret;
 128     }
 129 #else
 130     osslargused(file); osslargused(line);
 131 #endif
 132     return realloc(str, num);
 133
 134 }
 135
 136 void *CRYPTO_clear_realloc(void *str, size_t old_len, size_t num,
 137                            const char *file, int line)
 138 {
 139     void *ret = NULL;
 140
 141     if (str == NULL)
 142         return CRYPTO_malloc(num, file, line);
 143
 144     if (num == 0) {
 145         CRYPTO_clear_free(str, old_len, file, line);
 146         return NULL;
 147     }
 148
 149     /* Can't shrink the buffer since memcpy below copies |old_len| bytes. */
 150     if (num < old_len) {
 151         memset((char*)str + num, 0, old_len - num);
 152         return str;
 153     }
 154
 155     ret = CRYPTO_malloc(num, file, line);
 156     if (ret != NULL) {
 157         memcpy(ret, str, old_len);
 158         CRYPTO_clear_free(str, old_len, file, line);
 159     }
 160     return ret;
 161 }
 162
 163 void CRYPTO_free(void *str, const char *file, int line)
 164 {
 165     if (free_impl != NULL && free_impl != &CRYPTO_free) {
 166         free_impl(str, file, line);
 167         return;
 168     }
 169
 170 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
 171     if (call_malloc_debug) {
 172         CRYPTO_mem_debug_free(str, 0, file, line);
 173         free(str);
 174         CRYPTO_mem_debug_free(str, 1, file, line);
 175     } else {
 176         free(str);
 177     }
 178 #else
 179     free(str);
 180 #endif
 181 }
 182
 183 void CRYPTO_clear_free(void *str, size_t num, const char *file, int line)
 184 {
 185     if (str == NULL)
 186         return;
 187     if (num)
 188         OPENSSL_cleanse(str, num);
 189     CRYPTO_free(str, file, line);
 190 }