mirror of
https://github.com/openssl/openssl.git
synced 2024-12-09 05:51:54 +08:00
4746f25ac6
[skip ci] Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/7829)
69 lines
1.7 KiB
Plaintext
69 lines
1.7 KiB
Plaintext
=pod
|
|
|
|
=head1 NAME
|
|
|
|
BN_zero, BN_one, BN_value_one, BN_set_word, BN_get_word - BIGNUM assignment
|
|
operations
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/bn.h>
|
|
|
|
void BN_zero(BIGNUM *a);
|
|
int BN_one(BIGNUM *a);
|
|
|
|
const BIGNUM *BN_value_one(void);
|
|
|
|
int BN_set_word(BIGNUM *a, BN_ULONG w);
|
|
unsigned BN_ULONG BN_get_word(BIGNUM *a);
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
B<BN_ULONG> is a macro that will be an unsigned integral type optimized
|
|
for the most efficient implementation on the local platform.
|
|
|
|
BN_zero(), BN_one() and BN_set_word() set B<a> to the values 0, 1 and
|
|
B<w> respectively. BN_zero() and BN_one() are macros.
|
|
|
|
BN_value_one() returns a B<BIGNUM> constant of value 1. This constant
|
|
is useful for use in comparisons and assignment.
|
|
|
|
BN_get_word() returns B<a>, if it can be represented as a B<BN_ULONG>.
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
BN_get_word() returns the value B<a>, or all-bits-set if B<a> cannot
|
|
be represented as a single integer.
|
|
|
|
BN_one() and BN_set_word() return 1 on success, 0 otherwise.
|
|
BN_value_one() returns the constant.
|
|
BN_zero() never fails and returns no value.
|
|
|
|
=head1 BUGS
|
|
|
|
If a B<BIGNUM> is equal to the value of all-bits-set, it will collide
|
|
with the error condition returned by BN_get_word() which uses that
|
|
as an error value.
|
|
|
|
B<BN_ULONG> should probably be a typedef.
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<BN_bn2bin(3)>
|
|
|
|
=head1 HISTORY
|
|
|
|
In OpenSSL 0.9.8, BN_zero() was changed to not return a value; previous
|
|
versions returned an int.
|
|
|
|
=head1 COPYRIGHT
|
|
|
|
Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
|
|
|
|
Licensed under the Apache License 2.0 (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
|
|
L<https://www.openssl.org/source/license.html>.
|
|
|
|
=cut
|