/*

 * Copyright 1995-2024 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include "internal/e_os.h"

#include "internal/cryptlib.h"

#include "internal/mem_alloc_utils.h"

#include "crypto/cryptlib.h"

#include <stdio.h>

#include <stdlib.h>

#include <limits.h>

#include <openssl/crypto.h>

/*

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

 */

static int allow_customize = 1;

static CRYPTO_malloc_fn malloc_impl = CRYPTO_malloc;

static CRYPTO_realloc_fn realloc_impl = CRYPTO_realloc;

static CRYPTO_free_fn free_impl = CRYPTO_free;

#if !defined(OPENSSL_NO_CRYPTO_MDEBUG) && !defined(FIPS_MODULE)

# include "internal/tsan_assist.h"

# ifdef TSAN_REQUIRES_LOCKING

#  define INCREMENT(x) /* empty */

#  define LOAD(x) 0

# else  /* TSAN_REQUIRES_LOCKING */

static TSAN_QUALIFIER int malloc_count;

static TSAN_QUALIFIER int realloc_count;

static TSAN_QUALIFIER int free_count;

#  define INCREMENT(x) tsan_counter(&(x))

#  define LOAD(x)      tsan_load(&x)

# endif /* TSAN_REQUIRES_LOCKING */

static char md_failbuf[CRYPTO_MEM_CHECK_MAX_FS + 1];

static char *md_failstring = NULL;

static long md_count;

static int md_fail_percent = 0;

static int md_tracefd = -1;

static void parseit(void);

static int shouldfail(void);

# define FAILTEST() if (shouldfail()) return NULL

#else

# define INCREMENT(x) /* empty */

# define FAILTEST() /* empty */

#endif

int CRYPTO_set_mem_functions(CRYPTO_malloc_fn malloc_fn,

                             CRYPTO_realloc_fn realloc_fn,

                             CRYPTO_free_fn free_fn)

{

    if (!allow_customize)

        return 0;

    if (malloc_fn != NULL)

        malloc_impl = malloc_fn;

    if (realloc_fn != NULL)

        realloc_impl = realloc_fn;

    if (free_fn != NULL)

        free_impl = free_fn;

    return 1;

}

void CRYPTO_get_mem_functions(CRYPTO_malloc_fn *malloc_fn,

                              CRYPTO_realloc_fn *realloc_fn,

                              CRYPTO_free_fn *free_fn)

{

    if (malloc_fn != NULL)

        *malloc_fn = malloc_impl;

    if (realloc_fn != NULL)

        *realloc_fn = realloc_impl;

    if (free_fn != NULL)

        *free_fn = free_impl;

}

#if !defined(OPENSSL_NO_CRYPTO_MDEBUG) && !defined(FIPS_MODULE)

void CRYPTO_get_alloc_counts(int *mcount, int *rcount, int *fcount)

{

    if (mcount != NULL)

        *mcount = LOAD(malloc_count);

    if (rcount != NULL)

        *rcount = LOAD(realloc_count);

    if (fcount != NULL)

        *fcount = LOAD(free_count);

}

/*

 * Parse a "malloc failure spec" string.  This likes like a set of fields

 * separated by semicolons.  Each field has a count and an optional failure

 * percentage.  For example:

 *          100@0;100@25;0@0

 *    or    100;100@25;0

 * This means 100 mallocs succeed, then next 100 fail 25% of the time, and

 * all remaining (count is zero) succeed.

 * The failure percentge can have 2 digits after the comma.  For example:

 *          0@0.01

 * This means 0.01% of all allocations will fail.

 */

static void parseit(void)

{

    char *semi = strchr(md_failstring, ';');

    char *atsign;

    if (semi != NULL)

        *semi++ = '\0';

    /* Get the count (atol will stop at the @ if there), and percentage */

    md_count = atol(md_failstring);

    atsign = strchr(md_failstring, '@');

    md_fail_percent = atsign == NULL ? 0 : (int)(atof(atsign + 1) * 100 + 0.5);

    if (semi != NULL)

        md_failstring = semi;

}

/*

 * Windows doesn't have random() and srandom(), but it has rand() and srand().

 * Some rand() implementations aren't good, but we're not

 * dealing with secure randomness here.

 */

# ifdef _WIN32

#  define random() rand()

#  define srandom(seed) srand(seed)

# endif

/*

 * See if the current malloc should fail.

 */

static int shouldfail(void)

{

    int roll = (int)(random() % 10000);

    int shoulditfail = roll < md_fail_percent;

# ifndef _WIN32

/* suppressed on Windows as POSIX-like file descriptors are non-inheritable */

    int len;

    char buff[80];

    if (md_tracefd > 0) {

        BIO_snprintf(buff, sizeof(buff),

                     "%c C%ld %%%d R%d\n",

                     shoulditfail ? '-' : '+', md_count, md_fail_percent, roll);

        len = strlen(buff);

        if (write(md_tracefd, buff, len) != len)

            perror("shouldfail write failed");

    }

# endif

    if (md_count) {

        /* If we used up this one, go to the next. */

        if (--md_count == 0)

            parseit();

    }

    return shoulditfail;

}

void ossl_malloc_setup_failures(void)

{

    const char *cp = getenv("OPENSSL_MALLOC_FAILURES");

    size_t cplen = 0;

    if (cp != NULL) {

        /* if the value is too long we'll just ignore it */

        cplen = strlen(cp);

        if (cplen <= CRYPTO_MEM_CHECK_MAX_FS) {

            strncpy(md_failbuf, cp, CRYPTO_MEM_CHECK_MAX_FS);

            md_failstring = md_failbuf;

            parseit();

        }

    }

    if ((cp = getenv("OPENSSL_MALLOC_FD")) != NULL)

        md_tracefd = atoi(cp);

    if ((cp = getenv("OPENSSL_MALLOC_SEED")) != NULL)

        srandom(atoi(cp));

}

#endif

void *CRYPTO_malloc(size_t num, const char *file, int line)

{

    void *ptr;

    INCREMENT(malloc_count);

    if (malloc_impl != CRYPTO_malloc) {

        ptr = malloc_impl(num, file, line);

        if (ptr != NULL || num == 0)

            return ptr;

        goto err;

    }

    if (ossl_unlikely(num == 0))

        return NULL;

    FAILTEST();

    if (allow_customize) {

        /*

         * Disallow customization after the first allocation. We only set this

         * if necessary to avoid a store to the same cache line on every

         * allocation.

         */

        allow_customize = 0;

    }

    ptr = malloc(num);

    if (ossl_likely(ptr != NULL))

        return ptr;

 err:

    ossl_report_alloc_err(file, line);

    return NULL;

}

void *CRYPTO_zalloc(size_t num, const char *file, int line)

{

    void *ret;

    ret = CRYPTO_malloc(num, file, line);

    if (ret != NULL)

        memset(ret, 0, num);

    return ret;

}

void *CRYPTO_aligned_alloc(size_t num, size_t alignment, void **freeptr,

                           const char *file, int line)

{

    size_t alloc_bytes;

    void *ret;

    *freeptr = NULL;

#if defined(OPENSSL_SMALL_FOOTPRINT)

    return NULL;

#endif

    /* Ensure that alignment is a power of two */

    if (alignment == 0 || (alignment & (alignment - 1)) != 0) {

        ossl_report_alloc_err_inv(file, line);

        return NULL;

    }

    /* Allow non-malloc() allocations as long as no malloc_impl is provided. */

    if (malloc_impl == CRYPTO_malloc) {

#if defined(_BSD_SOURCE) || (defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 200112L)

        int memalign_ret;

        /* posix_memalign() requires alignment to be at least sizeof(void *) */

        if (alignment < sizeof(void *))

            alignment = sizeof(void *);

        if ((memalign_ret = posix_memalign(&ret, alignment, num))) {

            ret = NULL;

            switch (memalign_ret) {

            case EINVAL:

                ossl_report_alloc_err_inv(file, line);

                break;

            case ENOMEM:

                ossl_report_alloc_err(file, line);

                break;

            }

        }

        *freeptr = ret;

        return ret;

#endif

    }

    /* we have to do this the hard way */

    /*

     * Note: Windows supports an _aligned_malloc call, but we choose

     * not to use it here, because allocations from that function

     * require that they be freed via _aligned_free.  Given that

     * we can't differentiate plain malloc blocks from blocks obtained

     * via _aligned_malloc, just avoid its use entirely

     */

    if (ossl_unlikely(!ossl_size_add(num, alignment, &alloc_bytes, file, line)))

        return NULL;

    /*

     * Step 1: Allocate an amount of memory that is <alignment>

     * bytes bigger than requested

     */

    *freeptr = CRYPTO_malloc(alloc_bytes, file, line);

    if (*freeptr == NULL)

        return NULL;

    /*

     * Step 2: Add <alignment - 1> bytes to the pointer

     * This will cross the alignment boundary that is

     * requested

     */

    ret = (void *)((char *)*freeptr + (alignment - 1));

    /*

     * Step 3: Use the alignment as a mask to translate the

     * least significant bits of the allocation at the alignment

     * boundary to 0.  ret now holds a pointer to the memory

     * buffer at the requested alignment

     * NOTE: It is a documented requirement that alignment be a

     * power of 2, which is what allows this to work

     */

    ret = (void *)((uintptr_t)ret & (uintptr_t)(~(alignment - 1)));

    return ret;

}

void *CRYPTO_realloc(void *str, size_t num, const char *file, int line)

{

    void *ret;

    INCREMENT(realloc_count);

    if (realloc_impl != CRYPTO_realloc) {

        ret = realloc_impl(str, num, file, line);

        if (num == 0 || ret != NULL)

            return ret;

        goto err;

    }

    if (str == NULL)

        return CRYPTO_malloc(num, file, line);

    if (num == 0) {

        CRYPTO_free(str, file, line);

        return NULL;

    }

    FAILTEST();

    ret = realloc(str, num);

err:

    if (num != 0 && ret == NULL)

        ossl_report_alloc_err(file, line);

    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) {

        CRYPTO_clear_free(str, old_len, file, line);

        return NULL;

    }

    /* Can't shrink the buffer since memcpy below copies |old_len| bytes. */

    if (num < old_len) {

        OPENSSL_cleanse((char*)str + num, old_len - num);

        return str;

    }

    ret = CRYPTO_malloc(num, file, line);

    if (ret != NULL) {

        memcpy(ret, str, old_len);

        CRYPTO_clear_free(str, old_len, file, line);

    }

    return ret;

}

void CRYPTO_free(void *str, const char *file, int line)

{

    INCREMENT(free_count);

    if (free_impl != CRYPTO_free) {

        free_impl(str, file, line);

        return;

    }

    free(str);

}

void CRYPTO_clear_free(void *str, size_t num, const char *file, int line)

{

    if (str == NULL)

        return;

    if (num)

        OPENSSL_cleanse(str, num);

    CRYPTO_free(str, file, line);

}

#if !defined(OPENSSL_NO_CRYPTO_MDEBUG)

# ifndef OPENSSL_NO_DEPRECATED_3_0

int CRYPTO_mem_ctrl(int mode)

{

    (void)mode;

    return -1;

}

int CRYPTO_set_mem_debug(int flag)

{

    (void)flag;

    return -1;

}

int CRYPTO_mem_debug_push(const char *info, const char *file, int line)

{

    (void)info; (void)file; (void)line;

    return 0;

}

int CRYPTO_mem_debug_pop(void)

{

    return 0;

}

void CRYPTO_mem_debug_malloc(void *addr, size_t num, int flag,

                             const char *file, int line)

{

    (void)addr; (void)num; (void)flag; (void)file; (void)line;

}

void CRYPTO_mem_debug_realloc(void *addr1, void *addr2, size_t num, int flag,

                              const char *file, int line)

{

    (void)addr1; (void)addr2; (void)num; (void)flag; (void)file; (void)line;

}

void CRYPTO_mem_debug_free(void *addr, int flag,

                           const char *file, int line)

{

    (void)addr; (void)flag; (void)file; (void)line;

}

int CRYPTO_mem_leaks(BIO *b)

{

    (void)b;

    return -1;

}

#  ifndef OPENSSL_NO_STDIO

int CRYPTO_mem_leaks_fp(FILE *fp)

{

    (void)fp;

    return -1;

}

#  endif

int CRYPTO_mem_leaks_cb(int (*cb)(const char *str, size_t len, void *u),

                        void *u)

{

    (void)cb; (void)u;

    return -1;

}

# endif

#endif