crypto/mem.c

   1 /* crypto/mem.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 <stdlib.h>
  61 #include <limits.h>
  62 #include <openssl/crypto.h>
  63 #include "internal/cryptlib.h"
  64
  65 /*
  66  * the following pointers may be changed as long as 'allow_customize' is set
  67  */
  68 static int allow_customize = 1;
  69
  70 static void *(*malloc_wrapper)(size_t, const char *, int)
  71     = CRYPTO_malloc;
  72 static void *(*realloc_wrapper)(void *, size_t, const char *, int)
  73     = CRYPTO_realloc;
  74 static void (*free_wrapper)(void *)
  75     = CRYPTO_free;
  76
  77 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
  78 static int call_malloc_debug = 1;
  79 #else
  80 static int call_malloc_debug = 0;
  81 #endif
  82
  83 int CRYPTO_set_mem_functions(
  84         void *(*m)(size_t, const char *, int),
  85         void *(*r)(void *, size_t, const char *, int),
  86         void (*f)(void *))
  87 {
  88     if (!allow_customize)
  89         return 0;
  90     if (m)
  91         malloc_wrapper = m;
  92     if (r)
  93         realloc_wrapper = r;
  94     if (f)
  95         free_wrapper = f;
  96     return 1;
  97 }
  98
  99 int CRYPTO_set_mem_debug(int flag)
 100 {
 101     if (!allow_customize)
 102         return 0;
 103     call_malloc_debug = flag;
 104     return 1;
 105 }
 106
 107 void CRYPTO_get_mem_functions(
 108         void *(**m)(size_t, const char *, int),
 109         void *(**r)(void *, size_t, const char *, int),
 110         void (**f)(void *))
 111 {
 112     if (m != NULL)
 113         *m = malloc_wrapper;
 114     if (r != NULL)
 115         *r = realloc_wrapper;
 116     if (f != NULL)
 117         *f = free_wrapper;
 118 }
 119
 120 void *CRYPTO_malloc(size_t num, const char *file, int line)
 121 {
 122     void *ret = NULL;
 123
 124     if (num <= 0)
 125         return NULL;
 126
 127     allow_customize = 0;
 128 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
 129     if (call_malloc_debug) {
 130         CRYPTO_mem_debug_malloc(NULL, num, 0, file, line);
 131         ret = malloc(num);
 132         CRYPTO_mem_debug_malloc(ret, num, 1, file, line);
 133     } else {
 134         ret = malloc(num);
 135     }
 136 #else
 137     (void)file;
 138     (void)line;
 139     ret = malloc(num);
 140 #endif
 141
 142 #ifndef OPENSSL_CPUID_OBJ
 143     /*
 144      * Create a dependency on the value of 'cleanse_ctr' so our memory
 145      * sanitisation function can't be optimised out. NB: We only do this for
 146      * >2Kb so the overhead doesn't bother us.
 147      */
 148     if (ret && (num > 2048)) {
 149         extern unsigned char cleanse_ctr;
 150         ((unsigned char *)ret)[0] = cleanse_ctr;
 151     }
 152 #endif
 153
 154     return ret;
 155 }
 156
 157 void *CRYPTO_zalloc(size_t num, const char *file, int line)
 158 {
 159     void *ret = CRYPTO_malloc(num, file, line);
 160
 161     if (ret != NULL)
 162         memset(ret, 0, num);
 163     return ret;
 164 }
 165
 166 void *CRYPTO_realloc(void *str, size_t num, const char *file, int line)
 167 {
 168     if (str == NULL)
 169         return CRYPTO_malloc(num, file, line);
 170
 171     if (num == 0) {
 172         CRYPTO_free(str);
 173         return NULL;
 174     }
 175
 176     allow_customize = 0;
 177 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
 178     if (call_malloc_debug) {
 179         void *ret;
 180         CRYPTO_mem_debug_realloc(str, NULL, num, 0, file, line);
 181         ret = realloc(str, num);
 182         CRYPTO_mem_debug_realloc(str, ret, num, 1, file, line);
 183         return ret;
 184     }
 185 #else
 186     (void)file;
 187     (void)line;
 188 #endif
 189     return realloc(str, num);
 190
 191 }
 192
 193 void *CRYPTO_clear_realloc(void *str, size_t old_len, size_t num,
 194                            const char *file, int line)
 195 {
 196     void *ret = NULL;
 197
 198     if (str == NULL)
 199         return CRYPTO_malloc(num, file, line);
 200
 201     if (num == 0) {
 202         CRYPTO_clear_free(str, old_len);
 203         return NULL;
 204     }
 205
 206     /* Can't shrink the buffer since memcpy below copies |old_len| bytes. */
 207     if (num < old_len) {
 208         memset((char*)str + num, 0, old_len - num);
 209         return str;
 210     }
 211
 212     /* Allocate new memory.  Call malloc and do a copy, so that we can
 213      * cleanse the old buffer. */
 214 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
 215     if (call_malloc_debug) {
 216         CRYPTO_mem_debug_realloc(str, NULL, num, 0, file, line);
 217         ret = malloc(num);
 218         CRYPTO_mem_debug_realloc(str, ret, num, 1, file, line);
 219     } else {
 220         ret = malloc(num);
 221     }
 222 #else
 223     (void)file;
 224     (void)line;
 225     ret = malloc(num);
 226 #endif
 227
 228     if (ret)
 229         memcpy(ret, str, old_len);
 230     CRYPTO_clear_free(str, old_len);
 231     return ret;
 232 }
 233
 234 void CRYPTO_free(void *str)
 235 {
 236 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
 237     if (call_malloc_debug) {
 238         CRYPTO_mem_debug_free(str, 0);
 239         free(str);
 240         CRYPTO_mem_debug_free(str, 1);
 241     } else {
 242         free(str);
 243     }
 244 #else
 245     free(str);
 246 #endif
 247 }
 248
 249 void CRYPTO_clear_free(void *str, size_t num)
 250 {
 251     if (str == NULL)
 252         return;
 253     if (num)
 254         OPENSSL_cleanse(str, num);
 255     CRYPTO_free(str);
 256 }