GNUNET_assert( 0 == gcry_mpi_test_bit (*r, nbits) );
++ctr;
/* We reject this FDH if either *r > n and retry with another ctr */
GNUNET_assert( 0 == gcry_mpi_test_bit (*r, nbits) );
++ctr;
/* We reject this FDH if either *r > n and retry with another ctr */