NAME    [Toc]    [Back]

       RAND_bytes, RAND_pseudo_bytes - Generate random data

SYNOPSIS    [Toc]    [Back]

       #include <openssl/rand.h>

       int RAND_bytes(
               unsigned    char    *buf,    int    num   );   int
       RAND_pseudo_bytes(
               unsigned char *buf, int num );

DESCRIPTION    [Toc]    [Back]

       The  RAND_bytes()  function  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.

       The  RAND_pseudo_bytes()  function  puts num pseudo-random
       bytes into buf. Pseudo-random byte sequences generated  by
       the  RAND_pseudo_bytes()  function  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 VALUES    [Toc]    [Back]

       The  RAND_bytes()  functon  returns 1 on success, 0 otherwise.
  The  error  code   can   be   obtained   by   using
       ERR_get_error().  The RAND_pseudo_bytes() function 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.

HISTORY    [Toc]    [Back]

       The RAND_bytes() function is available in all versions  of
       SSLeay  and  OpenSSL.  It has a return value since OpenSSL
       0.9.5.  The  RAND_pseudo_bytes()  function  was  added  in
       OpenSSL 0.9.5.

SEE ALSO    [Toc]    [Back]

       Functions: rand_ssl(3), err(3), RAND_add(3)



                                                    RAND_bytes(3)