/usr/man/cat.3/BN_clear_free.3(/usr/man/cat.3/BN_clear_free.3)

BN_new(3)                    OpenSSL                    BN_new(3)

NAME

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

SYNOPSIS

      #include <openssl/bn.h>

      BIGNUM *BN_new(void);

      void BN_init(BIGNUM *);

      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_init() initializes an existing uninitialized BIGNUM.

     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() returns a pointer to the BIGNUM initialised to the
     value 0.  If the allocation fails, it returns NULL and sets
     an error code that can be obtained by ERR_get_error(3).

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

SEE ALSO

     bn(3), ERR_get_error(3)

HISTORY

     BN_new(), BN_clear(), BN_free() and BN_clear_free() are
     available in all versions on SSLeay and OpenSSL.  BN_init()
     was added in SSLeay 0.9.1b.

1.0.2t               Last change: 2019-09-10                    1

See also BN_clear(3)
See also BN_free(3)
See also BN_init(3)
See also BN_new(3)