The program grub-mkpasswd-pbkdf2 generates password hashes for GRUB.
grub-mkpasswd-pbkdf2-c number--iteration-count=numberNumber of iterations of the underlying pseudo-random function. Defaults to 10000.
-l number--buflen=numberLength of the generated hash. Defaults to 64.
-s number--salt=numberLength of the salt. Defaults to 64.