You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
50 lines
1.5 KiB
50 lines
1.5 KiB
=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);
|
|
|
|
int RAND_pseudo_bytes(unsigned char *buf, int num);
|
|
|
|
=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() 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)|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(3)|rand(3)>, L<ERR_get_error(3)|ERR_get_error(3)>,
|
|
L<RAND_add(3)|RAND_add(3)>
|
|
|
|
=head1 HISTORY
|
|
|
|
RAND_bytes() is available in all versions of SSLeay and OpenSSL. It
|
|
has a return value since OpenSSL 0.9.5. RAND_pseudo_bytes() was added
|
|
in OpenSSL 0.9.5.
|
|
|
|
=cut
|
|
|