blue-loader-python/ledgerblue/verifyEndorsement2.py

56 lines
2.1 KiB
Python

"""
*******************************************************************************
* Ledger Blue
* (c) 2016 Ledger
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
********************************************************************************
"""
from .ecWrapper import PublicKey
import hashlib
import hmac
import binascii
import argparse
parser = argparse.ArgumentParser()
parser.add_argument("--key", help="The public endorsement key 2 to verify with (hex encoded)")
parser.add_argument("--codehash", help="The hash of the code associated to the endorsement request (hex encoded)")
parser.add_argument("--message", help="The message associated to the endorsement request (hex encoded)")
parser.add_argument("--signature", help="The signature to verify with (hex encoded)")
args = parser.parse_args()
if args.key == None:
raise Exception("Missing public key")
if args.codehash == None:
raise Exception("Missing code hash")
if args.message == None:
raise Exception("Missing message")
if args.signature == None:
raise Exception("Missing signature")
# prepare data
tweak = hmac.new(bytes(bytearray.fromhex(args.codehash)), bytes(bytearray.fromhex(args.key)), hashlib.sha256).digest()
m = hashlib.sha256()
m.update(bytes(bytearray.fromhex(args.message)))
digest = m.digest()
publicKey = PublicKey(bytes(bytearray.fromhex(args.key)), raw=True)
publicKey.tweak_add(bytes(tweak))
signature = publicKey.ecdsa_deserialize(bytes(bytearray.fromhex(args.signature)))
if not publicKey.ecdsa_verify(bytes(digest), signature, raw=True):
raise Exception("Endorsement not verified")
print("Endorsement verified")