1. Answer the following questions about CFB mode of operation: a. Write the decryption equation using the cryptography notations (E, P, C, K). You can consider the shift register operations as part of the encryption algorithm as shown below. K P₁ IV Encrypt P₂ Encrypt b. What happens if two messages are encrypted with the same key and IV? What can the attacker learn about the two messages just by looking at their ciphertexts? c. If an attacker recovers the IV used for a given encryption, but not the key, will they be able to decrypt a ciphertext encrypted with the recovered IV and a secret key?

1. Answer the following questions about CFB mode of operation: a. Write the decryption equation using the cryptography notations (E, P, C, K). You can consider the shift register operations as part of the encryption algorithm as shown below. K P₁ IV Encrypt P₂ Encrypt b. What happens if two messages are encrypted with the same key and IV? What can the attacker learn about the two messages just by looking at their ciphertexts? c. If an attacker recovers the IV used for a given encryption, but not the key, will they be able to decrypt a ciphertext encrypted with the recovered IV and a secret key?