Ideally, we shouldn't try to add u items in the DGK decryption map here, since we don't want to restrict the size of u. Instead, we should implement a mechanism similar to the one in ElGamal, where we leave a gap in the middle of the message space. For this we'll need to add an extra parameter to DGK representing the message space threshold, which can be smaller than u.
Ideally, we shouldn't try to add
uitems in the DGK decryption map here, since we don't want to restrict the size ofu. Instead, we should implement a mechanism similar to the one in ElGamal, where we leave a gap in the middle of the message space. For this we'll need to add an extra parameter to DGK representing the message space threshold, which can be smaller thanu.