I do not understand this problem. I tried my code down below.
It says,"can only sign or verify one file."
Using the hash function SHA‐512 and the key generated in Step 5,
sign the ciphertext
cipher.bin produced in Step 3 and the encrypted session key
cipherSK.bin from Step 4. Output the signatures to files named
This is what I tried.
openssl -sha512 -sign cipher.bin cipherSK.bin -out sigCipher.bin sigSK.bin
Let me know if you need the whole instructions.