5 BN_new, BN_init, BN_clear, BN_free, BN_clear_free - allocate and free BIGNUMs
9 #include <openssl/bn.h>
13 void BN_clear(BIGNUM *a);
15 void BN_free(BIGNUM *a);
17 void BN_clear_free(BIGNUM *a);
21 BN_new() allocates and initializes a B<BIGNUM> structure.
23 BN_clear() is used to destroy sensitive data such as keys when they
24 are no longer needed. It erases the memory used by B<a> and sets it
27 BN_free() frees the components of the B<BIGNUM>, and if it was created
28 by BN_new(), also the structure itself. BN_clear_free() additionally
29 overwrites the data before the memory is returned to the system.
33 BN_new() returns a pointer to the B<BIGNUM>. If the allocation fails,
34 it returns B<NULL> and sets an error code that can be obtained
35 by L<ERR_get_error(3)|ERR_get_error(3)>.
37 BN_clear(), BN_free() and BN_clear_free() have no return values.
39 =head1 REMOVED FUNCTIONALITY
41 void BN_init(BIGNUM *);
43 BN_init() is no longer available as of OpenSSL 1.1.0. It was used to initialize
44 an existing uninitialized B<BIGNUM>. Typically this would be done as follows:
49 Applications should replace use of BN_init with BN_new instead:
53 if(!a) /* Handle error */
59 L<bn(3)|bn(3)>, L<ERR_get_error(3)|ERR_get_error(3)>
63 BN_new(), BN_clear(), BN_free() and BN_clear_free() are available in
64 all versions on SSLeay and OpenSSL. BN_init() was added in SSLeay
65 0.9.1b and removed in OpenSSL 1.1.0.