# Copyright (C) 2016-2018 Virgil Security Inc.
#
# Lead Maintainer: Virgil Security Inc. <support@virgilsecurity.com>
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# (1) Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
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# (2) Redistributions in binary form must reproduce the above copyright
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from virgil_crypto.hashes import HashAlgorithm
from virgil_crypto import VirgilCrypto
from virgil_crypto.keys import PrivateKey, PublicKey
[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], PrivateKey) -> bytearray
"""Signs the specified data using Private key.
Args:
data: raw data bytes for signing.
private_key: private key for signing.
Returns:
Signature bytes.
"""
if not private_key:
raise ValueError("Missing private key")
if not isinstance(private_key, PrivateKey):
raise ValueError("private_key must be a VirgilPrivateKey type")
return self.__crypto.sign(data, private_key)
[docs] def verify_signature(self, signature, data, public_key):
# type: (Union[bytes, bytearray], Union[bytes, bytearray], PublicKey) -> bool
"""Verifies the specified signature using original data and signer's public key.
Args:
data: original data bytes for verification.
signature: signature bytes for verification.
public_key: signer public key for verification.
Returns:
True if signature is valid, False otherwise.
"""
if not isinstance(public_key, PublicKey):
raise ValueError("public_key must be a VirgilPublicKey type")
return self.__crypto.verify(
data, signature, public_key
)
[docs] def export_public_key(self, public_key):
# type: (PublicKey) -> bytearray
"""Exports the Public key into material representation.
Args:
public_key: public key for export.
Returns:
Key material representation bytes.
"""
if not public_key:
raise ValueError("Missing public key")
return self.__crypto.export_public_key(public_key)
[docs] def import_public_key(self, data):
# type: (Union[bytes, bytearray]) -> PublicKey
"""Imports the Public key from material representation.
Args:
data: key material representation bytes.
Returns:
Imported public key.
"""
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.
"""
return self.__crypto.compute_hash(data, HashAlgorithm.SHA512)
@property
def crypto(self):
"""
Gets Virgil Crypto.
Returns:
Card Crypto
"""
return self.__crypto