# Copyright (C) 2016-2018 Virgil Security Inc.
#
# Lead Maintainer: Virgil Security Inc. <support@virgilsecurity.com>
#
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# (1) Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
#
# (2) Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in
# the documentation and/or other materials provided with the
# distribution.
#
# (3) Neither the name of the copyright holder nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ''AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
# INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
# IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
from virgil_crypto.hashes import HashAlgorithm
from virgil_crypto import VirgilCrypto
from virgil_crypto.keys import VirgilPrivateKey, VirgilPublicKey
[docs]class CardCrypto(object):
"""Cards cryptographic operations.
Class provides a cryptographic operations for Cards.
"""
def __init__(self, crypto=VirgilCrypto()):
self.__crypto = crypto
[docs] def generate_signature(self, data, private_key):
# type: (Union[bytes, bytearray], VirgilPrivateKey) -> bytearray
"""Signs the specified data using Private key.
Args:
data: raw data bytes for signing.
private_key: private key for signing.
Returns:
Signature bytes.
Raises:
ValueError: if data or private key missing or malformed
"""
if not data:
raise ValueError("Missing data for signing")
if not private_key:
raise ValueError("Missing private key")
if not isinstance(private_key, VirgilPrivateKey):
raise ValueError("private_key must be a VirgilPrivateKey type")
return self.__crypto.generate_signature(data, private_key)
[docs] def verify_signature(self, signature, data, public_key):
# type: (Union[bytes, bytearray], Union[bytes, bytearray], VirgilPublicKey) -> bool
"""Verifies the specified signature using original data and signer's public key.
Args:
signature: signature bytes for verification.
data: original data bytes for verification.
public_key: signer public key for verification.
Returns:
True if signature is valid, False otherwise.
Raises:
ValueError: if data, signature, public key missing or malformed.
"""
if not signature:
raise ValueError("Missing signature")
if not data:
raise ValueError("Missing data for signature verify")
if not isinstance(public_key, VirgilPublicKey):
raise ValueError("public_key must be a VirgilPublicKey type")
return self.__crypto.verify_signature(
data, signature, public_key
)
[docs] def export_public_key(self, public_key):
# type: (VirgilPublicKey) -> bytearray
"""Exports the Public key into material representation.
Args:
public_key: public key for export.
Returns:
Key material representation bytes.
Raises:
ValueError: if public key missing or malformed.
"""
if not public_key:
raise ValueError("Missing public key")
if public_key.public_key is None or public_key.identifier is None or public_key.key_type is None:
raise ValueError("Public Key is not complete.")
return self.__crypto.export_public_key(public_key)
[docs] def import_public_key(self, data):
# type: (Union[bytes, bytearray]) -> VirgilPublicKey
"""Imports the Public key from material representation.
Args:
data: key material representation bytes.
Returns:
Imported public key.
Raises:
ValueError: if key data missing
"""
if not data:
raise ValueError("Key data missing")
return self.__crypto.import_public_key(data)
[docs] def generate_sha512(self, data):
# type: (Union[bytes, bytearray]) -> bytearray
"""Computes the sha512 hash of specified data.
Args:
data: data bytes for fingerprint calculation.
Returns:
Hash bytes.
Raises:
ValueError: if data missed.
"""
if not data:
raise ValueError("Missed data for fingerprint generation")
return self.__crypto.compute_hash(data, HashAlgorithm.SHA512)
@property
def crypto(self):
"""
Gets Virgil Crypto.
Returns:
Card Crypto
"""
return self.__crypto