1*2175Sjp161948=pod 2*2175Sjp161948 3*2175Sjp161948=head1 NAME 4*2175Sjp161948 5*2175Sjp161948RAND_bytes, RAND_pseudo_bytes - generate random data 6*2175Sjp161948 7*2175Sjp161948=head1 SYNOPSIS 8*2175Sjp161948 9*2175Sjp161948 #include <openssl/rand.h> 10*2175Sjp161948 11*2175Sjp161948 int RAND_bytes(unsigned char *buf, int num); 12*2175Sjp161948 13*2175Sjp161948 int RAND_pseudo_bytes(unsigned char *buf, int num); 14*2175Sjp161948 15*2175Sjp161948=head1 DESCRIPTION 16*2175Sjp161948 17*2175Sjp161948RAND_bytes() puts B<num> cryptographically strong pseudo-random bytes 18*2175Sjp161948into B<buf>. An error occurs if the PRNG has not been seeded with 19*2175Sjp161948enough randomness to ensure an unpredictable byte sequence. 20*2175Sjp161948 21*2175Sjp161948RAND_pseudo_bytes() puts B<num> pseudo-random bytes into B<buf>. 22*2175Sjp161948Pseudo-random byte sequences generated by RAND_pseudo_bytes() will be 23*2175Sjp161948unique if they are of sufficient length, but are not necessarily 24*2175Sjp161948unpredictable. They can be used for non-cryptographic purposes and for 25*2175Sjp161948certain purposes in cryptographic protocols, but usually not for key 26*2175Sjp161948generation etc. 27*2175Sjp161948 28*2175Sjp161948=head1 RETURN VALUES 29*2175Sjp161948 30*2175Sjp161948RAND_bytes() returns 1 on success, 0 otherwise. The error code can be 31*2175Sjp161948obtained by L<ERR_get_error(3)|ERR_get_error(3)>. RAND_pseudo_bytes() returns 1 if the 32*2175Sjp161948bytes generated are cryptographically strong, 0 otherwise. Both 33*2175Sjp161948functions return -1 if they are not supported by the current RAND 34*2175Sjp161948method. 35*2175Sjp161948 36*2175Sjp161948=head1 SEE ALSO 37*2175Sjp161948 38*2175Sjp161948L<rand(3)|rand(3)>, L<ERR_get_error(3)|ERR_get_error(3)>, 39*2175Sjp161948L<RAND_add(3)|RAND_add(3)> 40*2175Sjp161948 41*2175Sjp161948=head1 HISTORY 42*2175Sjp161948 43*2175Sjp161948RAND_bytes() is available in all versions of SSLeay and OpenSSL. It 44*2175Sjp161948has a return value since OpenSSL 0.9.5. RAND_pseudo_bytes() was added 45*2175Sjp161948in OpenSSL 0.9.5. 46*2175Sjp161948 47*2175Sjp161948=cut 48