NAME
BN_CTX_new
,
BN_CTX_free
—
allocate and free BN_CTX
structures
SYNOPSIS
#include
<openssl/bn.h>
BN_CTX *
BN_CTX_new
(void);
void
BN_CTX_free
(BN_CTX *c);
DESCRIPTION
A BN_CTX is a structure that holds BIGNUM temporary variables used by library functions. Since dynamic memory allocation to create BIGNUMs is rather expensive when used in conjunction with repeated subroutine calls, the BN_CTX structure is used.
BN_CTX_new
()
allocates and initializes a BN_CTX structure.
BN_CTX_free
()
frees the components of the BN_CTX and, if it was
created by BN_CTX_new
(), also the structure itself.
If BN_CTX_start(3)
has been used on the BN_CTX,
BN_CTX_end(3) must be
called before the BN_CTX may be freed by
BN_CTX_free
(). If c is a
NULL
pointer, no action occurs.
RETURN VALUES
BN_CTX_new
() returns a pointer to the
BN_CTX. If the allocation fails, it returns
NULL
and sets an error code that can be obtained by
ERR_get_error(3).
SEE ALSO
HISTORY
BN_CTX_new
() and
BN_CTX_free
() first appeared in SSLeay 0.5.1 and
have been available since OpenBSD 2.4.