RAND_bytes(3) OpenSSL RAND_bytes(3)NAME
RAND_bytes, RAND_pseudo_bytes - generate random data
SYNOPSIS
#include <openssl/rand.h>
int RAND_bytes(unsigned char *buf, int num);
int RAND_pseudo_bytes(unsigned char *buf, int num);
DESCRIPTIONRAND_bytes() puts num cryptographically strong pseudo-
random bytes into buf. An error occurs if the PRNG has not
been seeded with enough randomness to ensure an
unpredictable byte sequence.
RAND_pseudo_bytes() puts num pseudo-random bytes into 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.
RETURN VALUESRAND_bytes() returns 1 on success, 0 otherwise. The error
code can be obtained by 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.
SEE ALSOrand(3), err(3), RAND_add(3)HISTORYRAND_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.
16/Aug/2000 0.9.6 1