Return an N-bit random prime number, using random data obtained
from the function randfunc. randfunc must take a single
integer argument, and return a string of random data of the
corresponding length; the get_bytes() method of a
RandomPool object will serve the purpose nicely, as will the
read() method of an opened file such as /dev/random.
Return an N-bit random number, using random data obtained from the
function randfunc. As usual, randfunc must take a single
integer argument and return a string of random data of the
corresponding length.