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
|
|
|