NAME

       BN_new, BN_secure_new, BN_clear, BN_free, BN_clear_free - allocate and free BIGNUMs

SYNOPSIS

        #include <openssl/bn.h>

        BIGNUM *BN_new(void);

        BIGNUM *BN_secure_new(void);

        void BN_clear(BIGNUM *a);

        void BN_free(BIGNUM *a);

        void BN_clear_free(BIGNUM *a);

DESCRIPTION

       BN_new() allocates and initializes a BIGNUM structure.  BN_secure_new() does the same
       except that the secure heap OPENSSL_secure_malloc(3) is used to store the value.

       BN_clear() is used to destroy sensitive data such as keys when they are no longer needed.
       It erases the memory used by a and sets it to the value 0.

       BN_free() frees the components of the BIGNUM, and if it was created by BN_new(), also the
       structure itself. BN_clear_free() additionally overwrites the data before the memory is
       returned to the system.  If a is NULL, nothing is done.

RETURN VALUES

       BN_new() and BN_secure_new() return a pointer to the BIGNUM initialised to the value 0.
       If the allocation fails, they return NULL and set an error code that can be obtained by
       ERR_get_error(3).

       BN_clear(), BN_free() and BN_clear_free() have no return values.

SEE ALSO

       ERR_get_error(3)

HISTORY

       BN_init() was removed in OpenSSL 1.1.0; use BN_new() instead.

COPYRIGHT

       Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the OpenSSL license (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>.