const BIGNUM *from);
BN_dup(const BIGNUM *from);
const BIGNUM *b, int flags);
copies from to to.
creates a new BIGNUM containing the value
shallow copy of b in dest. It
places significant restrictions on the copied data. Applications that do not
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 can be used to create a temporary
copy of a BIGNUM with the
BN_FLG_CONSTTIME flag set for constant time
The temporary copy in dest will share 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(3). 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 declared "const".
- dest must be used and freed before any further subsequent use of b.
BN_copy() returns to
on success or
NULL on error.
BN_dup() returns the new
NULL on error. The
error codes can be obtained by
BN_dup() first appeared in SSLeay 0.5.1 and have
been available since OpenBSD 2.4.
BN_with_flags() first appeared in OpenSSL
0.9.7h and 0.9.8a and has been available since OpenBSD