=head1 NAME
-BN_rand, BN_pseudo_rand - generate pseudo-random number
+BN_rand, BN_pseudo_rand, BN_rand_range, BN_pseudo_rand_range - generate pseudo-random number
=head1 SYNOPSIS
int BN_pseudo_rand(BIGNUM *rnd, int bits, int top, int bottom);
- int BN_rand_range(BIGNUM *rnd, BIGNUM *min, BIGNUM *max);
+ int BN_rand_range(BIGNUM *rnd, BIGNUM *range);
+
+ int BN_pseudo_rand_range(BIGNUM *rnd, BIGNUM *range);
=head1 DESCRIPTION
BN_rand() generates a cryptographically strong pseudo-random number of
-B<bits> bits in length and stores it in B<rnd>. If B<top> is true, the
-two most significant bits of the number will be set to 1, so that the
-product of two such random numbers will always have 2*B<bits> length.
-If B<bottom> is true, the number will be odd.
+B<bits> bits in length and stores it in B<rnd>. If B<top> is -1, the
+most significant bit of the random number can be zero. If B<top> is 0,
+it is set to 1, and if B<top> is 1, the two most significant bits of
+the number will be set to 1, so that the product of two such random
+numbers will always have 2*B<bits> length. If B<bottom> is true, the
+number will be odd.
BN_pseudo_rand() does the same, but pseudo-random numbers generated by
this function are not necessarily unpredictable. They can be used for
protocols, but usually not for key generation etc.
BN_rand_range() generates a cryptographically strong pseudo-random
-number B<rnd> in the range B<min> E<lt>= B<rnd> E<lt> B<max>. B<min>
-may be NULL, in that case 0 E<lt>= B<rnd> E<lt> B<max>.
+number B<rnd> in the range 0 <lt>= B<rnd> E<lt> B<range>.
+BN_pseudo_rand_range() does the same, but is based on BN_pseudo_rand(),
+and hence numbers generated by it are not necessarily unpredictable.
The PRNG must be seeded prior to calling BN_rand() or BN_rand_range().
=head1 SEE ALSO
-L<bn(3)|bn(3)>, L<err(3)|err(3)>, L<rand(3)|rand(3)>,
+L<bn(3)|bn(3)>, L<ERR_get_error(3)|ERR_get_error(3)>, L<rand(3)|rand(3)>,
L<RAND_add(3)|RAND_add(3)>, L<RAND_bytes(3)|RAND_bytes(3)>
=head1 HISTORY
BN_rand() is available in all versions of SSLeay and OpenSSL.
-BN_pseudo_rand() was added in OpenSSL 0.9.5, and BN_rand_range()
-in OpenSSL 0.9.6a.
+BN_pseudo_rand() was added in OpenSSL 0.9.5. The B<top> == -1 case
+and the function BN_rand_range() were added in OpenSSL 0.9.6a.
+BN_pseudo_rand_range() was added in OpenSSL 0.9.6c.
=cut