The one-time pad is often described with a simple XOR cipher.
This is nice for showing the theoretical strengths of the one-time pad, but not so great in real-world scenarios where key reuse is a danger.
So, is it feasible to use an n-bit block cipher with an n-bit key to replace the XOR operation (which itself is a 1-bit block cipher with a 1-bit key)?
So the encryption operation becomes
for each pBlock is n bits of plaintext
take kBlock as the corresponding n bits of the key
encrypt pBlock with kBlock as key using the block cipher and the result is cBlock
append cBlock to the ciphertext
Decryption is the same.
Am I correct that this will make it more resistant (but not fully) to key reuse and known plaintext attacks than using the simple XOR? Or did I add a big vulnerability into the scheme?