Manual Page Result
0
Command: BN_copy | Section: 3 | Source: OpenBSD | File: BN_copy.3
BN_COPY(3) FreeBSD Library Functions Manual BN_COPY(3)
NAME
BN_copy, BN_dup, BN_with_flags - copy BIGNUMs
SYNOPSIS
#include <openssl/bn.h>
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);
DESCRIPTION
BN_copy() copies from to to.
BN_dup() creates a new BIGNUM containing the value from.
BN_with_flags() creates a temporary 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
operations.
The temporary copy in dest will share some internal state with b. For
this reason, the following restrictions apply to the use of dest:
o 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.
o dest must only be used in "read-only" operations, i.e. typically
those functions where the relevant parameter is declared "const".
o dest must be used and freed before any further subsequent use of b.
RETURN VALUES
BN_copy() returns to on success or NULL on error. BN_dup() returns the
new BIGNUM or NULL on error. The error codes can be obtained by
ERR_get_error(3).
SEE ALSO
BN_new(3), BN_set_flags(3)
HISTORY
BN_copy() and 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 4.0.
FreeBSD 14.1-RELEASE-p8 December 6, 2021 FreeBSD 14.1-RELEASE-p8