1=pod 2 3=head1 NAME 4 5RAND_bytes, RAND_pseudo_bytes - generate random data 6 7=head1 SYNOPSIS 8 9 #include <openssl/rand.h> 10 11 int RAND_bytes(unsigned char *buf, int num); 12 13 int RAND_pseudo_bytes(unsigned char *buf, int num); 14 15=head1 DESCRIPTION 16 17RAND_bytes() puts B<num> cryptographically strong pseudo-random bytes 18into B<buf>. An error occurs if the PRNG has not been seeded with 19enough randomness to ensure an unpredictable byte sequence. 20 21RAND_pseudo_bytes() puts B<num> pseudo-random bytes into B<buf>. 22Pseudo-random byte sequences generated by RAND_pseudo_bytes() will be 23unique if they are of sufficient length, but are not necessarily 24unpredictable. They can be used for non-cryptographic purposes and for 25certain purposes in cryptographic protocols, but usually not for key 26generation etc. 27 28=head1 RETURN VALUES 29 30RAND_bytes() returns 1 on success, 0 otherwise. The error code can be 31obtained by L<ERR_get_error(3)|ERR_get_error(3)>. RAND_pseudo_bytes() returns 1 if the 32bytes generated are cryptographically strong, 0 otherwise. Both 33functions return -1 if they are not supported by the current RAND 34method. 35 36=head1 SEE ALSO 37 38L<rand(3)|rand(3)>, L<ERR_get_error(3)|ERR_get_error(3)>, 39L<RAND_add(3)|RAND_add(3)> 40 41=head1 HISTORY 42 43RAND_bytes() is available in all versions of SSLeay and OpenSSL. It 44has a return value since OpenSSL 0.9.5. RAND_pseudo_bytes() was added 45in OpenSSL 0.9.5. 46 47=cut 48