#Drew Pasley from cryptography.hazmat.primitives.asymmetric import ec from cryptography.hazmat.primitives import hashes from cryptography.exceptions import InvalidSignature #hint: try to adopt code from https://cryptography.io/en/latest/hazmat/primitives/asymmetric/ec.html #hint: try to use sample codes (i.e., code in the green boxes) # finish the implementation def generate_keys(): private_key = ec.generate_private_key(ec.SECP384R1()) public_key = private_key.public_key() return private_key, public_key # finish the implementation def sign(private_key, digest): signature = private_key.sign( data, ec.ECDSA(hashes.SHA256())) return signature # finish the implementation def verify(signature, public_key, data): try: public_key.verify(signature, data, ec.ECDSA(hashes.SHA256())) except InvalidSignature: print("Invalid") # put your test cases here print("testing valid input(should have no output)") if __name__ == '__main__': prv, pub = generate_keys() data = b"this is some data I'd like to sign" sig = sign(prv, data) verify(sig, pub, data) print("testing invalid unencrypted message") data_new = b"this is modified data" verify(sig, pub, data_new) print("testing of tampered signiture") pr_fake, pu_fake = generate_keys() sig_fake = sign(pr_fake, data) verify(sig_fake, pub, data) print("complete")