mirror of
https://github.com/openkmip/pykmip
synced 2025-12-15 07:43:26 +00:00
60bd56066e
This change adds decryption functionality to the cryptographic engine used by the server. It supports a variety of symmetric decryption algorithms and block cipher modes. Asymmetric decryption support will be added in a future patch. Unit tests and minor updates to surrounding code are included.
622 lines
25 KiB
Python
622 lines
25 KiB
Python
# Copyright (c) 2016 The Johns Hopkins University/Applied Physics Laboratory
|
|
# All Rights Reserved.
|
|
#
|
|
# 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.
|
|
|
|
import logging
|
|
import os
|
|
|
|
from cryptography.hazmat.backends import default_backend
|
|
from cryptography.hazmat.primitives import serialization, hashes, hmac, cmac
|
|
from cryptography.hazmat.primitives import padding as symmetric_padding
|
|
from cryptography.hazmat.primitives.asymmetric import rsa
|
|
from cryptography.hazmat.primitives.asymmetric import padding as \
|
|
asymmetric_padding
|
|
from cryptography.hazmat.primitives import ciphers
|
|
from cryptography.hazmat.primitives.ciphers import algorithms, modes
|
|
|
|
from kmip.core import enums
|
|
from kmip.core import exceptions
|
|
from kmip.services.server.crypto import api
|
|
|
|
|
|
class CryptographyEngine(api.CryptographicEngine):
|
|
"""
|
|
A cryptographic engine that uses pyca/cryptography to generate
|
|
cryptographic objects and conduct cryptographic operations.
|
|
"""
|
|
|
|
def __init__(self):
|
|
"""
|
|
Construct a CryptographyEngine.
|
|
"""
|
|
self.logger = logging.getLogger('kmip.server.engine.cryptography')
|
|
|
|
# The IDEA algorithm is supported by cryptography but may not be
|
|
# supported by certain backends, like OpenSSL.
|
|
self._symmetric_key_algorithms = {
|
|
enums.CryptographicAlgorithm.TRIPLE_DES: algorithms.TripleDES,
|
|
enums.CryptographicAlgorithm.AES: algorithms.AES,
|
|
enums.CryptographicAlgorithm.BLOWFISH: algorithms.Blowfish,
|
|
enums.CryptographicAlgorithm.CAMELLIA: algorithms.Camellia,
|
|
enums.CryptographicAlgorithm.CAST5: algorithms.CAST5,
|
|
enums.CryptographicAlgorithm.IDEA: algorithms.IDEA,
|
|
enums.CryptographicAlgorithm.RC4: algorithms.ARC4
|
|
}
|
|
self._asymmetric_key_algorithms = {
|
|
enums.CryptographicAlgorithm.RSA: self._create_rsa_key_pair
|
|
}
|
|
self._hash_algorithms = {
|
|
enums.CryptographicAlgorithm.HMAC_SHA1: hashes.SHA1,
|
|
enums.CryptographicAlgorithm.HMAC_SHA224: hashes.SHA224,
|
|
enums.CryptographicAlgorithm.HMAC_SHA256: hashes.SHA256,
|
|
enums.CryptographicAlgorithm.HMAC_SHA384: hashes.SHA384,
|
|
enums.CryptographicAlgorithm.HMAC_SHA512: hashes.SHA512,
|
|
enums.CryptographicAlgorithm.HMAC_MD5: hashes.MD5
|
|
}
|
|
|
|
# TODO(peter-hamilton): Consider merging above hash dict and this one
|
|
self._encryption_hash_algorithms = {
|
|
enums.HashingAlgorithm.MD5: hashes.MD5,
|
|
enums.HashingAlgorithm.SHA_1: hashes.SHA1,
|
|
enums.HashingAlgorithm.SHA_224: hashes.SHA224,
|
|
enums.HashingAlgorithm.SHA_256: hashes.SHA256,
|
|
enums.HashingAlgorithm.SHA_384: hashes.SHA384,
|
|
enums.HashingAlgorithm.SHA_512: hashes.SHA512
|
|
}
|
|
|
|
# GCM is supported by cryptography but requires inputs that are not
|
|
# supported by the KMIP spec. It is excluded for now.
|
|
self._modes = {
|
|
enums.BlockCipherMode.CBC: modes.CBC,
|
|
enums.BlockCipherMode.ECB: modes.ECB,
|
|
enums.BlockCipherMode.OFB: modes.OFB,
|
|
enums.BlockCipherMode.CFB: modes.CFB,
|
|
enums.BlockCipherMode.CTR: modes.CTR
|
|
}
|
|
self._asymmetric_padding_methods = {
|
|
enums.PaddingMethod.OAEP: asymmetric_padding.OAEP,
|
|
enums.PaddingMethod.PKCS1v15: asymmetric_padding.PKCS1v15
|
|
}
|
|
self._symmetric_padding_methods = {
|
|
enums.PaddingMethod.ANSI_X923: symmetric_padding.ANSIX923,
|
|
enums.PaddingMethod.PKCS5: symmetric_padding.PKCS7
|
|
}
|
|
self._no_mode_needed = [
|
|
enums.CryptographicAlgorithm.RC4
|
|
]
|
|
self._no_padding_needed = [
|
|
enums.BlockCipherMode.CTR,
|
|
enums.BlockCipherMode.OFB,
|
|
enums.BlockCipherMode.CFB,
|
|
enums.BlockCipherMode.GCM
|
|
]
|
|
|
|
def create_symmetric_key(self, algorithm, length):
|
|
"""
|
|
Create a symmetric key.
|
|
|
|
Args:
|
|
algorithm(CryptographicAlgorithm): An enumeration specifying the
|
|
algorithm for which the created key will be compliant.
|
|
length(int): The length of the key to be created. This value must
|
|
be compliant with the constraints of the provided algorithm.
|
|
|
|
Returns:
|
|
dict: A dictionary containing the key data, with the following
|
|
key/value fields:
|
|
* value - the bytes of the key
|
|
* format - a KeyFormatType enumeration for the bytes format
|
|
|
|
Raises:
|
|
InvalidField: Raised when the algorithm is unsupported or the
|
|
length is incompatible with the algorithm.
|
|
CryptographicFailure: Raised when the key generation process
|
|
fails.
|
|
|
|
Example:
|
|
>>> engine = CryptographyEngine()
|
|
>>> key = engine.create_symmetric_key(
|
|
... CryptographicAlgorithm.AES, 256)
|
|
"""
|
|
if algorithm not in self._symmetric_key_algorithms.keys():
|
|
raise exceptions.InvalidField(
|
|
"The cryptographic algorithm {0} is not a supported symmetric "
|
|
"key algorithm.".format(algorithm)
|
|
)
|
|
|
|
cryptography_algorithm = self._symmetric_key_algorithms.get(algorithm)
|
|
|
|
if length not in cryptography_algorithm.key_sizes:
|
|
raise exceptions.InvalidField(
|
|
"The cryptographic length ({0}) is not valid for "
|
|
"the cryptographic algorithm ({1}).".format(
|
|
length, algorithm.name
|
|
)
|
|
)
|
|
|
|
self.logger.info(
|
|
"Generating a {0} symmetric key with length: {1}".format(
|
|
algorithm.name, length
|
|
)
|
|
)
|
|
|
|
key_bytes = os.urandom(length // 8)
|
|
try:
|
|
cryptography_algorithm(key_bytes)
|
|
except Exception as e:
|
|
self.logger.exception(e)
|
|
raise exceptions.CryptographicFailure(
|
|
"Invalid bytes for the provided cryptographic algorithm.")
|
|
|
|
return {'value': key_bytes, 'format': enums.KeyFormatType.RAW}
|
|
|
|
def create_asymmetric_key_pair(self, algorithm, length):
|
|
"""
|
|
Create an asymmetric key pair.
|
|
|
|
Args:
|
|
algorithm(CryptographicAlgorithm): An enumeration specifying the
|
|
algorithm for which the created keys will be compliant.
|
|
length(int): The length of the keys to be created. This value must
|
|
be compliant with the constraints of the provided algorithm.
|
|
|
|
Returns:
|
|
dict: A dictionary containing the public key data, with at least
|
|
the following key/value fields:
|
|
* value - the bytes of the key
|
|
* format - a KeyFormatType enumeration for the bytes format
|
|
dict: A dictionary containing the private key data, identical in
|
|
structure to the one above.
|
|
|
|
Raises:
|
|
InvalidField: Raised when the algorithm is unsupported or the
|
|
length is incompatible with the algorithm.
|
|
CryptographicFailure: Raised when the key generation process
|
|
fails.
|
|
|
|
Example:
|
|
>>> engine = CryptographyEngine()
|
|
>>> key = engine.create_asymmetric_key(
|
|
... CryptographicAlgorithm.RSA, 2048)
|
|
"""
|
|
if algorithm not in self._asymmetric_key_algorithms.keys():
|
|
raise exceptions.InvalidField(
|
|
"The cryptographic algorithm ({0}) is not a supported "
|
|
"asymmetric key algorithm.".format(algorithm)
|
|
)
|
|
|
|
engine_method = self._asymmetric_key_algorithms.get(algorithm)
|
|
return engine_method(length)
|
|
|
|
def mac(self, algorithm, key, data):
|
|
"""
|
|
Generate message authentication code.
|
|
|
|
Args:
|
|
algorithm(CryptographicAlgorithm): An enumeration specifying the
|
|
algorithm for which the MAC operation will use.
|
|
key(bytes): secret key used in the MAC operation
|
|
data(bytes): The data to be MACed.
|
|
|
|
Returns:
|
|
bytes: The MACed data
|
|
|
|
Raises:
|
|
InvalidField: Raised when the algorithm is unsupported or the
|
|
length is incompatible with the algorithm.
|
|
CryptographicFailure: Raised when the key generation process
|
|
fails.
|
|
|
|
Example:
|
|
>>> engine = CryptographyEngine()
|
|
>>> mac_data = engine.mac(
|
|
... CryptographicAlgorithm.HMAC-SHA256, b'\x01\x02\x03\x04',
|
|
... b'\x05\x06\x07\x08')
|
|
"""
|
|
|
|
mac_data = None
|
|
|
|
if algorithm in self._hash_algorithms.keys():
|
|
self.logger.info(
|
|
"Generating a hash-based message authentication code using "
|
|
"{0}".format(algorithm.name)
|
|
)
|
|
hash_algorithm = self._hash_algorithms.get(algorithm)
|
|
try:
|
|
h = hmac.HMAC(key, hash_algorithm(), backend=default_backend())
|
|
h.update(data)
|
|
mac_data = h.finalize()
|
|
except Exception as e:
|
|
self.logger.exception(e)
|
|
raise exceptions.CryptographicFailure(
|
|
"An error occurred while computing an HMAC. "
|
|
"See the server log for more information."
|
|
)
|
|
elif algorithm in self._symmetric_key_algorithms.keys():
|
|
self.logger.info(
|
|
"Generating a cipher-based message authentication code using "
|
|
"{0}".format(algorithm.name)
|
|
)
|
|
cipher_algorithm = self._symmetric_key_algorithms.get(algorithm)
|
|
try:
|
|
# ARC4 and IDEA algorithms will raise exception as CMAC
|
|
# requires block ciphers
|
|
c = cmac.CMAC(cipher_algorithm(key), backend=default_backend())
|
|
c.update(data)
|
|
mac_data = c.finalize()
|
|
except Exception as e:
|
|
raise exceptions.CryptographicFailure(
|
|
"An error occurred while computing a CMAC. "
|
|
"See the server log for more information."
|
|
)
|
|
else:
|
|
raise exceptions.InvalidField(
|
|
"The cryptographic algorithm ({0}) is not a supported "
|
|
"for a MAC operation.".format(algorithm)
|
|
)
|
|
return mac_data
|
|
|
|
def encrypt(self,
|
|
encryption_algorithm,
|
|
encryption_key,
|
|
plain_text,
|
|
cipher_mode=None,
|
|
padding_method=None,
|
|
iv_nonce=None):
|
|
"""
|
|
Encrypt data using symmetric encryption.
|
|
|
|
Args:
|
|
encryption_algorithm (CryptographicAlgorithm): An enumeration
|
|
specifying the symmetric encryption algorithm to use for
|
|
encryption.
|
|
encryption_key (bytes): The bytes of the symmetric key to use for
|
|
encryption.
|
|
plain_text (bytes): The bytes to be encrypted.
|
|
cipher_mode (BlockCipherMode): An enumeration specifying the
|
|
block cipher mode to use with the encryption algorithm.
|
|
Required in the general case. Optional if the encryption
|
|
algorithm is RC4 (aka ARC4). If optional, defaults to None.
|
|
padding_method (PaddingMethod): An enumeration specifying the
|
|
padding method to use on the data before encryption. Required
|
|
if the cipher mode is for block ciphers (e.g., CBC, ECB).
|
|
Optional otherwise, defaults to None.
|
|
iv_nonce (bytes): The IV/nonce value to use to initialize the mode
|
|
of the encryption algorithm. Optional, defaults to None. If
|
|
required and not provided, it will be autogenerated and
|
|
returned with the cipher text.
|
|
|
|
Returns:
|
|
dict: A dictionary containing the encrypted data, with at least
|
|
the following key/value fields:
|
|
* cipher_text - the bytes of the encrypted data
|
|
* iv_nonce - the bytes of the IV/counter/nonce used if it
|
|
was needed by the encryption scheme and if it was
|
|
automatically generated for the encryption
|
|
|
|
Raises:
|
|
InvalidField: Raised when the algorithm is unsupported or the
|
|
length is incompatible with the algorithm.
|
|
CryptographicFailure: Raised when the key generation process
|
|
fails.
|
|
|
|
Example:
|
|
>>> engine = CryptographyEngine()
|
|
>>> result = engine.encrypt(
|
|
... encryption_algorithm=CryptographicAlgorithm.AES,
|
|
... encryption_key=(
|
|
... b'\xF3\x96\xE7\x1C\xCF\xCD\xEC\x1F'
|
|
... b'\xFC\xE2\x8E\xA6\xF8\x74\x28\xB0'
|
|
... ),
|
|
... plain_text=(
|
|
... b'\x00\x01\x02\x03\x04\x05\x06\x07'
|
|
... b'\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F'
|
|
... ),
|
|
... cipher_mode=BlockCipherMode.CBC,
|
|
... padding_method=PaddingMethod.ANSI_X923,
|
|
... )
|
|
>>> result.get('cipher_text')
|
|
b'\x18[\xb9y\x1bL\xd1\x8f\x9a\xa0e\x02b\xa3=c'
|
|
>>> result.iv_counter_nonce
|
|
b'8qA\x05\xc4\x86\x03\xd9=\xef\xdf\xb8ke\x9a\xa2'
|
|
"""
|
|
|
|
# Set up the algorithm
|
|
if encryption_algorithm is None:
|
|
raise exceptions.InvalidField("Encryption algorithm is required.")
|
|
algorithm = self._symmetric_key_algorithms.get(
|
|
encryption_algorithm,
|
|
None
|
|
)
|
|
if algorithm is None:
|
|
raise exceptions.InvalidField(
|
|
"Encryption algorithm '{0}' is not a supported symmetric "
|
|
"encryption algorithm.".format(encryption_algorithm)
|
|
)
|
|
try:
|
|
algorithm = algorithm(encryption_key)
|
|
except Exception as e:
|
|
self.logger.exception(e)
|
|
raise exceptions.CryptographicFailure(
|
|
"Invalid key bytes for the specified encryption algorithm."
|
|
)
|
|
|
|
# Set up the cipher mode if needed
|
|
return_iv_nonce = False
|
|
if encryption_algorithm == enums.CryptographicAlgorithm.RC4:
|
|
mode = None
|
|
else:
|
|
if cipher_mode is None:
|
|
raise exceptions.InvalidField("Cipher mode is required.")
|
|
mode = self._modes.get(cipher_mode, None)
|
|
if mode is None:
|
|
raise exceptions.InvalidField(
|
|
"Cipher mode '{0}' is not a supported mode.".format(
|
|
cipher_mode
|
|
)
|
|
)
|
|
if hasattr(mode, 'initialization_vector') or \
|
|
hasattr(mode, 'nonce'):
|
|
if iv_nonce is None:
|
|
iv_nonce = os.urandom(algorithm.block_size // 8)
|
|
return_iv_nonce = True
|
|
mode = mode(iv_nonce)
|
|
else:
|
|
mode = mode()
|
|
|
|
# Pad the plain text if needed (separate methods for testing purposes)
|
|
if cipher_mode in [
|
|
enums.BlockCipherMode.CBC,
|
|
enums.BlockCipherMode.ECB
|
|
]:
|
|
plain_text = self._handle_symmetric_padding(
|
|
self._symmetric_key_algorithms.get(encryption_algorithm),
|
|
plain_text,
|
|
padding_method
|
|
)
|
|
|
|
# Encrypt the plain text
|
|
cipher = ciphers.Cipher(algorithm, mode, backend=default_backend())
|
|
encryptor = cipher.encryptor()
|
|
cipher_text = encryptor.update(plain_text) + encryptor.finalize()
|
|
|
|
if return_iv_nonce:
|
|
return {
|
|
'cipher_text': cipher_text,
|
|
'iv_nonce': iv_nonce
|
|
}
|
|
else:
|
|
return {'cipher_text': cipher_text}
|
|
|
|
def _handle_symmetric_padding(self,
|
|
algorithm,
|
|
plain_text,
|
|
padding_method,
|
|
undo_padding=False):
|
|
# KMIP 1.3 test TC-STREAM-ENC-2-13.xml demonstrates a case
|
|
# where an encrypt call for 3DES-ECB does not use padding if
|
|
# the plaintext fits the blocksize of the algorithm. This does
|
|
# not appear to be documented explicitly in the KMIP spec. It
|
|
# also makes failures during unpadding after decryption
|
|
# impossible to differentiate from cipher text/key mismatches.
|
|
# For now, ALWAYS apply padding regardless of plain text length.
|
|
if padding_method in self._symmetric_padding_methods.keys():
|
|
padding_method = self._symmetric_padding_methods.get(
|
|
padding_method
|
|
)
|
|
if undo_padding:
|
|
padder = padding_method(algorithm.block_size).unpadder()
|
|
else:
|
|
padder = padding_method(algorithm.block_size).padder()
|
|
plain_text = padder.update(plain_text)
|
|
plain_text += padder.finalize()
|
|
else:
|
|
if padding_method is None:
|
|
raise exceptions.InvalidField(
|
|
"Padding method is required."
|
|
)
|
|
else:
|
|
raise exceptions.InvalidField(
|
|
"Padding method '{0}' is not supported.".format(
|
|
padding_method
|
|
)
|
|
)
|
|
return plain_text
|
|
|
|
def decrypt(self,
|
|
decryption_algorithm,
|
|
decryption_key,
|
|
cipher_text,
|
|
cipher_mode=None,
|
|
padding_method=None,
|
|
iv_nonce=None):
|
|
"""
|
|
Decrypt data using symmetric decryption.
|
|
|
|
Args:
|
|
decryption_algorithm (CryptographicAlgorithm): An enumeration
|
|
specifying the symmetric decryption algorithm to use for
|
|
decryption.
|
|
decryption_key (bytes): The bytes of the symmetric key to use for
|
|
decryption.
|
|
cipher_text (bytes): The bytes to be decrypted.
|
|
cipher_mode (BlockCipherMode): An enumeration specifying the
|
|
block cipher mode to use with the decryption algorithm.
|
|
Required in the general case. Optional if the decryption
|
|
algorithm is RC4 (aka ARC4). If optional, defaults to None.
|
|
padding_method (PaddingMethod): An enumeration specifying the
|
|
padding method to use on the data after decryption. Required
|
|
if the cipher mode is for block ciphers (e.g., CBC, ECB).
|
|
Optional otherwise, defaults to None.
|
|
iv_nonce (bytes): The IV/nonce value to use to initialize the mode
|
|
of the decryption algorithm. Optional, defaults to None.
|
|
|
|
Returns:
|
|
bytes: the bytes of the decrypted data
|
|
|
|
Raises:
|
|
InvalidField: Raised when the algorithm is unsupported or the
|
|
length is incompatible with the algorithm.
|
|
CryptographicFailure: Raised when the key generation process
|
|
fails.
|
|
|
|
Example:
|
|
>>> engine = CryptographyEngine()
|
|
>>> result = engine.decrypt(
|
|
... decryption_algorithm=CryptographicAlgorithm.AES,
|
|
... decryption_key=(
|
|
... b'\xF3\x96\xE7\x1C\xCF\xCD\xEC\x1F'
|
|
... b'\xFC\xE2\x8E\xA6\xF8\x74\x28\xB0'
|
|
... ),
|
|
... cipher_text=(
|
|
... b'\x18\x5B\xB9\x79\x1B\x4C\xD1\x8F'
|
|
... b'\x9A\xA0\x65\x02\x62\xA3\x3D\x63'
|
|
... ),
|
|
... cipher_mode=BlockCipherMode.CBC,
|
|
... padding_method=PaddingMethod.ANSI_X923,
|
|
... iv_nonce=(
|
|
... b'\x38\x71\x41\x05\xC4\x86\x03\xD9'
|
|
... b'\x3D\xEF\xDF\xB8\x6B\x65\x9A\xA2'
|
|
... )
|
|
... )
|
|
>>> result
|
|
b'\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f'
|
|
"""
|
|
|
|
# Set up the algorithm
|
|
if decryption_algorithm is None:
|
|
raise exceptions.InvalidField("Decryption algorithm is required.")
|
|
algorithm = self._symmetric_key_algorithms.get(
|
|
decryption_algorithm,
|
|
None
|
|
)
|
|
if algorithm is None:
|
|
raise exceptions.InvalidField(
|
|
"Decryption algorithm '{0}' is not a supported symmetric "
|
|
"decryption algorithm.".format(decryption_algorithm)
|
|
)
|
|
try:
|
|
algorithm = algorithm(decryption_key)
|
|
except Exception as e:
|
|
self.logger.exception(e)
|
|
raise exceptions.CryptographicFailure(
|
|
"Invalid key bytes for the specified decryption algorithm."
|
|
)
|
|
|
|
# Set up the cipher mode if needed
|
|
if decryption_algorithm == enums.CryptographicAlgorithm.RC4:
|
|
mode = None
|
|
else:
|
|
if cipher_mode is None:
|
|
raise exceptions.InvalidField("Cipher mode is required.")
|
|
mode = self._modes.get(cipher_mode, None)
|
|
if mode is None:
|
|
raise exceptions.InvalidField(
|
|
"Cipher mode '{0}' is not a supported mode.".format(
|
|
cipher_mode
|
|
)
|
|
)
|
|
if hasattr(mode, 'initialization_vector') or \
|
|
hasattr(mode, 'nonce'):
|
|
if iv_nonce is None:
|
|
raise exceptions.InvalidField(
|
|
"IV/nonce is required."
|
|
)
|
|
mode = mode(iv_nonce)
|
|
else:
|
|
mode = mode()
|
|
|
|
# Decrypt the plain text
|
|
cipher = ciphers.Cipher(algorithm, mode, backend=default_backend())
|
|
decryptor = cipher.decryptor()
|
|
plain_text = decryptor.update(cipher_text) + decryptor.finalize()
|
|
|
|
# Unpad the plain text if needed (separate methods for testing
|
|
# purposes)
|
|
if cipher_mode in [
|
|
enums.BlockCipherMode.CBC,
|
|
enums.BlockCipherMode.ECB
|
|
]:
|
|
plain_text = self._handle_symmetric_padding(
|
|
self._symmetric_key_algorithms.get(decryption_algorithm),
|
|
plain_text,
|
|
padding_method
|
|
)
|
|
|
|
return plain_text
|
|
|
|
def _create_rsa_key_pair(self, length, public_exponent=65537):
|
|
"""
|
|
Create an RSA key pair.
|
|
|
|
Args:
|
|
length(int): The length of the keys to be created. This value must
|
|
be compliant with the constraints of the provided algorithm.
|
|
public_exponent(int): The value of the public exponent needed to
|
|
generate the keys. Usually a small Fermat prime number.
|
|
Optional, defaults to 65537.
|
|
|
|
Returns:
|
|
dict: A dictionary containing the public key data, with the
|
|
following key/value fields:
|
|
* value - the bytes of the key
|
|
* format - a KeyFormatType enumeration for the bytes format
|
|
* public_exponent - the public exponent integer
|
|
dict: A dictionary containing the private key data, identical in
|
|
structure to the one above.
|
|
|
|
Raises:
|
|
CryptographicFailure: Raised when the key generation process
|
|
fails.
|
|
"""
|
|
self.logger.info(
|
|
"Generating an RSA key pair with length: {0}, and "
|
|
"public_exponent: {1}".format(
|
|
length, public_exponent
|
|
)
|
|
)
|
|
try:
|
|
private_key = rsa.generate_private_key(
|
|
public_exponent=public_exponent,
|
|
key_size=length,
|
|
backend=default_backend())
|
|
public_key = private_key.public_key()
|
|
|
|
private_bytes = private_key.private_bytes(
|
|
serialization.Encoding.DER,
|
|
serialization.PrivateFormat.PKCS8,
|
|
serialization.NoEncryption())
|
|
public_bytes = public_key.public_bytes(
|
|
serialization.Encoding.DER,
|
|
serialization.PublicFormat.PKCS1)
|
|
except Exception as e:
|
|
self.logger.exception(e)
|
|
raise exceptions.CryptographicFailure(
|
|
"An error occurred while generating the RSA key pair. "
|
|
"See the server log for more information."
|
|
)
|
|
|
|
public_key = {
|
|
'value': public_bytes,
|
|
'format': enums.KeyFormatType.PKCS_1,
|
|
'public_exponent': public_exponent
|
|
}
|
|
private_key = {
|
|
'value': private_bytes,
|
|
'format': enums.KeyFormatType.PKCS_8,
|
|
'public_exponent': public_exponent
|
|
}
|
|
|
|
return public_key, private_key
|