mirror of
https://github.com/openssl/openssl.git
synced 2024-12-09 05:51:54 +08:00
b97fdb57a2
Reviewed-by: Rich Salz <rsalz@openssl.org> (Merged from https://github.com/openssl/openssl/pull/1900)
59 lines
1.7 KiB
Plaintext
59 lines
1.7 KiB
Plaintext
=pod
|
|
|
|
=head1 NAME
|
|
|
|
RAND_bytes, RAND_pseudo_bytes - generate random data
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/rand.h>
|
|
|
|
int RAND_bytes(unsigned char *buf, int num);
|
|
|
|
Deprecated:
|
|
|
|
#if OPENSSL_API_COMPAT < 0x10100000L
|
|
int RAND_pseudo_bytes(unsigned char *buf, int num);
|
|
#endif
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
RAND_bytes() puts B<num> cryptographically strong pseudo-random bytes
|
|
into B<buf>. An error occurs if the PRNG has not been seeded with
|
|
enough randomness to ensure an unpredictable byte sequence.
|
|
|
|
RAND_pseudo_bytes() has been deprecated. Users should use RAND_bytes() instead.
|
|
RAND_pseudo_bytes() puts B<num> pseudo-random bytes into B<buf>.
|
|
Pseudo-random byte sequences generated by RAND_pseudo_bytes() will be
|
|
unique if they are of sufficient length, but are not necessarily
|
|
unpredictable. They can be used for non-cryptographic purposes and for
|
|
certain purposes in cryptographic protocols, but usually not for key
|
|
generation etc.
|
|
|
|
The contents of B<buf> is mixed into the entropy pool before retrieving
|
|
the new pseudo-random bytes unless disabled at compile time (see FAQ).
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
RAND_bytes() returns 1 on success, 0 otherwise. The error code can be
|
|
obtained by L<ERR_get_error(3)>. RAND_pseudo_bytes() returns 1 if the
|
|
bytes generated are cryptographically strong, 0 otherwise. Both
|
|
functions return -1 if they are not supported by the current RAND
|
|
method.
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<RAND_bytes(3)>, L<ERR_get_error(3)>,
|
|
L<RAND_add(3)>
|
|
|
|
=head1 COPYRIGHT
|
|
|
|
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
|
|
L<https://www.openssl.org/source/license.html>.
|
|
|
|
=cut
|