BN_copy, BN_dup, BN_with_flags - copy BIGNUMs
BIGNUM *BN_copy(BIGNUM *to, const BIGNUM *from);
BIGNUM *BN_dup(const BIGNUM *from);
void BN_with_flags(BIGNUM *dest, const BIGNUM *b, int flags);
creates a new
containing the value from
BN_with_flags creates a temporary
shallow copy of b
. It places significant restrictions on the copied data.
Applications that do no adhere to these restrictions may encounter unexpected
side effects or crashes. For that reason use of this function is discouraged.
Any flags provided in flags
will be set in dest
in addition to
any flags already set in b
. For example this might commonly be used to
create a temporary copy of a BIGNUM with the BN_FLG_CONSTTIME
for constant time operations. The temporary copy in dest
some internal state with b
. For this reason the following restrictions
apply to the use of dest
- dest should be a newly allocated BIGNUM obtained via
a call to BN_new(). It should not have been used for other purposes
or initialised in any way.
- dest must only be used in "read-only"
operations, i.e. typically those functions where the relevant parameter is
- dest must be used and freed before any further
subsequent use of b
on success, NULL on error. BN_dup()
returns the new BIGNUM
, and NULL on error. The error codes can be
obtained by ERR_get_error
Copyright 2000-2016 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