openssl/crypto/mem.c

/* crypto/mem.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <stdio.h>
#include <stdlib.h>
#include <openssl/crypto.h>
#include "internal/cryptlib.h"

static int allow_customize = 1; /* we provide flexible functions for */
static int allow_customize_debug = 1; /* exchanging memory-related functions
                                       * at run-time, but this must be done
                                       * before any blocks are actually
                                       * allocated; or we'll run into huge
                                       * problems when malloc/free pairs
                                       * don't match etc. */

/*
 * the following pointers may be changed as long as 'allow_customize' is set
 */

static void *(*malloc_func) (size_t) = malloc;
static void *default_malloc_ex(size_t num, const char *file, int line)
{
    return malloc_func(num);
}

static void *(*malloc_ex_func) (size_t, const char *file, int line)
    = default_malloc_ex;

static void *(*realloc_func) (void *, size_t) = realloc;
static void *default_realloc_ex(void *str, size_t num,
                                const char *file, int line)
{
    return realloc_func(str, num);
}

static void *(*realloc_ex_func) (void *, size_t, const char *file, int line)
    = default_realloc_ex;

static void (*free_func) (void *) = free;

static void *(*malloc_secure_func)(size_t) = malloc;
static void *default_malloc_secure_ex(size_t num, const char *file, int line)
{
    return malloc_secure_func(num);
}
static void *(*malloc_secure_ex_func)(size_t, const char *file, int line)
    = default_malloc_secure_ex;
static void (*free_secure_func)(void *) = free;

/* may be changed as long as 'allow_customize_debug' is set */
/* XXX use correct function pointer types */
#ifdef CRYPTO_MDEBUG
/* use default functions from mem_dbg.c */
static void (*malloc_debug_func) (void *, size_t, const char *, int, int)
    = CRYPTO_dbg_malloc;
static void (*realloc_debug_func) (void *, void *, size_t, const char *, int,
                                   int)
    = CRYPTO_dbg_realloc;
static void (*free_debug_func) (void *, int) = CRYPTO_dbg_free;
static void (*set_debug_options_func) (long) = CRYPTO_dbg_set_options;
static long (*get_debug_options_func) (void) = CRYPTO_dbg_get_options;
#else
/*
 * applications can use CRYPTO_malloc_debug_init() to select above case at
 * run-time
 */
static void (*malloc_debug_func) (void *, size_t, const char *, int, int) = NULL;
static void (*realloc_debug_func) (void *, void *, size_t, const char *, int,
                                   int)
    = NULL;
static void (*free_debug_func) (void *, int) = NULL;
static void (*set_debug_options_func) (long) = NULL;
static long (*get_debug_options_func) (void) = NULL;
#endif

int CRYPTO_set_mem_functions(void *(*m) (size_t), void *(*r) (void *, size_t),
                             void (*f) (void *))
{
    /* Dummy call just to ensure OPENSSL_init() gets linked in */
    OPENSSL_init();
    if (!allow_customize)
        return 0;
    if ((m == 0) || (r == 0) || (f == 0))
        return 0;
    malloc_func = m;
    malloc_ex_func = default_malloc_ex;
    realloc_func = r;
    realloc_ex_func = default_realloc_ex;
    free_func = f;
    /* If user wants to intercept the secure or locked functions, do it
     * after the basic functions. */
    malloc_secure_func = m;
    malloc_secure_ex_func = default_malloc_secure_ex;
    free_secure_func = f;
    return 1;
}

int CRYPTO_set_mem_ex_functions(void *(*m) (size_t, const char *, int),
                                void *(*r) (void *, size_t, const char *,
                                            int), void (*f) (void *))
{
    if (!allow_customize)
        return 0;
    if ((m == 0) || (r == 0) || (f == 0))
        return 0;
    malloc_func = 0;
    malloc_ex_func = m;
    realloc_func = 0;
    realloc_ex_func = r;
    free_func = f;
    malloc_secure_func = 0;
    malloc_secure_ex_func = m;
    free_secure_func = f;
    return 1;
}

int CRYPTO_set_secure_mem_functions(void *(*m)(size_t), void (*f)(void *))
{
    /* Dummy call just to ensure OPENSSL_init() gets linked in */
    OPENSSL_init();
    if (!allow_customize)
        return 0;
    if ((m == 0) || (f == 0))
        return 0;
    malloc_secure_func = m;
    malloc_secure_ex_func = default_malloc_secure_ex;
    free_secure_func = f;
    return 1;
}

int CRYPTO_set_secure_mem_ex_functions(void *(*m)(size_t, const char *, int),
                                       void (*f)(void *))
{
    if (!allow_customize)
        return 0;
    if ((m == NULL) || (f == NULL))
        return 0;
    malloc_secure_func = 0;
    malloc_secure_ex_func = m;
    free_secure_func = f;
    return 1;
}

int CRYPTO_set_mem_debug_functions(void (*m) (void *, size_t,
                                              const char *, int, int),
                                   void (*r) (void *, void *, size_t,
                                              const char *, int, int),
                                   void (*f) (void *, int), void (*so) (long),
                                   long (*go) (void))
{
    if (!allow_customize_debug)
        return 0;
    malloc_debug_func = m;
    realloc_debug_func = r;
    free_debug_func = f;
    set_debug_options_func = so;
    get_debug_options_func = go;
    return 1;
}

void CRYPTO_get_mem_functions(void *(**m) (size_t),
                              void *(**r) (void *, size_t),
                              void (**f) (void *))
{
    if (m != NULL)
        *m = (malloc_ex_func == default_malloc_ex) ? malloc_func : 0;
    if (r != NULL)
        *r = (realloc_ex_func == default_realloc_ex) ? realloc_func : 0;
    if (f != NULL)
        *f = free_func;
}

void CRYPTO_get_mem_ex_functions(void *(**m) (size_t, const char *, int),
                                 void *(**r) (void *, size_t, const char *,
                                              int), void (**f) (void *))
{
    if (m != NULL)
        *m = (malloc_ex_func != default_malloc_ex) ? malloc_ex_func : 0;
    if (r != NULL)
        *r = (realloc_ex_func != default_realloc_ex) ? realloc_ex_func : 0;
    if (f != NULL)
        *f = free_func;
}

void CRYPTO_get_secure_mem_functions(void *(**m)(size_t), void (**f)(void *))
{
    if (m != NULL)
        *m = (malloc_secure_ex_func == default_malloc_secure_ex) ?
            malloc_secure_func : 0;
    if (f != NULL)
        *f=free_secure_func;
}

void CRYPTO_get_secure_mem_ex_functions(void *(**m)(size_t,const char *,int),
                                        void (**f)(void *))
{
    if (m != NULL)
        *m = (malloc_secure_ex_func != default_malloc_secure_ex) ?
            malloc_secure_ex_func : 0;
    if (f != NULL)
        *f=free_secure_func;
}

void CRYPTO_get_mem_debug_functions(void (**m) (void *, size_t,
                                                const char *, int, int),
                                    void (**r) (void *, void *, size_t,
                                                const char *, int, int),
                                    void (**f) (void *, int),
                                    void (**so) (long), long (**go) (void))
{
    if (m != NULL)
        *m = malloc_debug_func;
    if (r != NULL)
        *r = realloc_debug_func;
    if (f != NULL)
        *f = free_debug_func;
    if (so != NULL)
        *so = set_debug_options_func;
    if (go != NULL)
        *go = get_debug_options_func;
}

void *CRYPTO_malloc(size_t num, const char *file, int line)
{
    void *ret = NULL;

    if (num <= 0)
        return NULL;

    if (allow_customize)
        allow_customize = 0;
    if (malloc_debug_func != NULL) {
        if (allow_customize_debug)
            allow_customize_debug = 0;
        malloc_debug_func(NULL, num, file, line, 0);
    }
    ret = malloc_ex_func(num, file, line);
    if (malloc_debug_func != NULL)
        malloc_debug_func(ret, num, file, line, 1);

#ifndef OPENSSL_CPUID_OBJ
    /*
     * Create a dependency on the value of 'cleanse_ctr' so our memory
     * sanitisation function can't be optimised out. NB: We only do this for
     * >2Kb so the overhead doesn't bother us.
     */
    if (ret && (num > 2048)) {
        extern unsigned char cleanse_ctr;
        ((unsigned char *)ret)[0] = cleanse_ctr;
    }
#endif

    return ret;
}

void *CRYPTO_zalloc(size_t num, const char *file, int line)
{
    void *ret = CRYPTO_malloc(num, file, line);

    if (ret != NULL)
        memset(ret, 0, num);
    return ret;
}

void *CRYPTO_realloc(void *str, size_t num, const char *file, int line)
{
    void *ret = NULL;

    if (str == NULL)
        return CRYPTO_malloc(num, file, line);

    if (num <= 0)
        return NULL;

    if (realloc_debug_func != NULL)
        realloc_debug_func(str, NULL, num, file, line, 0);
    ret = realloc_ex_func(str, num, file, line);
    if (realloc_debug_func != NULL)
        realloc_debug_func(str, ret, num, file, line, 1);

    return ret;
}

void *CRYPTO_clear_realloc(void *str, size_t old_len, size_t num,
                           const char *file, int line)
{
    void *ret = NULL;

    if (str == NULL)
        return CRYPTO_malloc(num, file, line);

    if (num <= 0)
        return NULL;

    /*
     * We don't support shrinking the buffer. Note the memcpy that copies
     * |old_len| bytes to the new buffer, below.
     */
    if (num < old_len)
        return NULL;

    if (realloc_debug_func != NULL)
        realloc_debug_func(str, NULL, num, file, line, 0);
    ret = malloc_ex_func(num, file, line);
    if (ret) {
        memcpy(ret, str, old_len);
        OPENSSL_clear_free(str, old_len);
    }
    if (realloc_debug_func != NULL)
        realloc_debug_func(str, ret, num, file, line, 1);

    return ret;
}

void CRYPTO_free(void *str)
{
    if (free_debug_func != NULL)
        free_debug_func(str, 0);
    free_func(str);
    if (free_debug_func != NULL)
        free_debug_func(NULL, 1);
}

void CRYPTO_clear_free(void *str, size_t num)
{
    if (!str)
        return;
    if (num)
        OPENSSL_cleanse(str, num);
    CRYPTO_free(str);
}

void CRYPTO_set_mem_debug_options(long bits)
{
    if (set_debug_options_func != NULL)
        set_debug_options_func(bits);
}

long CRYPTO_get_mem_debug_options(void)
{
    if (get_debug_options_func != NULL)
        return get_debug_options_func();
    return 0;
}