We know that the generic formula for encryption and decryption for block cipher is that C...

 

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We know that the generic formula for encryption and decryption for block cipher is that C = E(P,K), and P = D(C,K). Suppose we use a new block cipher, which looks similar but actually different from CBC mode, to encrypt plaintexts according to the following rules: Co IV E (Po, K), C = Co E(P, K), C = C E(P, K) What are the corresponding decryption rules for Po, P1, P2? Please write them out for Po, P1, P2, respectively. We know that the generic formula for encryption and decryption for block cipher is that C = E(P,K), and P = D(C,K). Suppose we use a new block cipher, which looks similar but actually different from CBC mode, to encrypt plaintexts according to the following rules: Co IV E (Po, K), C = Co E(P, K), C = C E(P, K) What are the corresponding decryption rules for Po, P1, P2? Please write them out for Po, P1, P2, respectively.