community.crypto/plugins/module_utils/crypto/support.py

402 lines
15 KiB
Python

# -*- coding: utf-8 -*-
#
# Copyright (c) 2016, Yanis Guenane <yanis+ansible@guenane.org>
# GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
# SPDX-License-Identifier: GPL-3.0-or-later
from __future__ import absolute_import, division, print_function
__metaclass__ = type
import abc
import datetime
import errno
import hashlib
import os
import re
from ansible.module_utils import six
from ansible.module_utils.common.text.converters import to_native, to_bytes
try:
from OpenSSL import crypto
HAS_PYOPENSSL = True
except (ImportError, AttributeError):
# Error handled in the calling module.
HAS_PYOPENSSL = False
try:
from cryptography import x509
from cryptography.hazmat.backends import default_backend as cryptography_backend
from cryptography.hazmat.primitives.serialization import load_pem_private_key
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives import serialization
except ImportError:
# Error handled in the calling module.
pass
from .basic import (
OpenSSLObjectError,
OpenSSLBadPassphraseError,
)
# This list of preferred fingerprints is used when prefer_one=True is supplied to the
# fingerprinting methods.
PREFERRED_FINGERPRINTS = (
'sha256', 'sha3_256', 'sha512', 'sha3_512', 'sha384', 'sha3_384', 'sha1', 'md5'
)
def get_fingerprint_of_bytes(source, prefer_one=False):
"""Generate the fingerprint of the given bytes."""
fingerprint = {}
try:
algorithms = hashlib.algorithms
except AttributeError:
try:
algorithms = hashlib.algorithms_guaranteed
except AttributeError:
return None
if prefer_one:
# Sort algorithms to have the ones in PREFERRED_FINGERPRINTS at the beginning
prefered_algorithms = [algorithm for algorithm in PREFERRED_FINGERPRINTS if algorithm in algorithms]
prefered_algorithms += sorted([algorithm for algorithm in algorithms if algorithm not in PREFERRED_FINGERPRINTS])
algorithms = prefered_algorithms
for algo in algorithms:
f = getattr(hashlib, algo)
try:
h = f(source)
except ValueError:
# This can happen for hash algorithms not supported in FIPS mode
# (https://github.com/ansible/ansible/issues/67213)
continue
try:
# Certain hash functions have a hexdigest() which expects a length parameter
pubkey_digest = h.hexdigest()
except TypeError:
pubkey_digest = h.hexdigest(32)
fingerprint[algo] = ':'.join(pubkey_digest[i:i + 2] for i in range(0, len(pubkey_digest), 2))
if prefer_one:
break
return fingerprint
def get_fingerprint_of_privatekey(privatekey, backend='cryptography', prefer_one=False):
"""Generate the fingerprint of the public key. """
if backend == 'cryptography':
publickey = privatekey.public_key().public_bytes(
serialization.Encoding.DER,
serialization.PublicFormat.SubjectPublicKeyInfo
)
return get_fingerprint_of_bytes(publickey, prefer_one=prefer_one)
def get_fingerprint(path, passphrase=None, content=None, backend='cryptography', prefer_one=False):
"""Generate the fingerprint of the public key. """
privatekey = load_privatekey(path, passphrase=passphrase, content=content, check_passphrase=False, backend=backend)
return get_fingerprint_of_privatekey(privatekey, backend=backend, prefer_one=prefer_one)
def load_privatekey(path, passphrase=None, check_passphrase=True, content=None, backend='cryptography'):
"""Load the specified OpenSSL private key.
The content can also be specified via content; in that case,
this function will not load the key from disk.
"""
try:
if content is None:
with open(path, 'rb') as b_priv_key_fh:
priv_key_detail = b_priv_key_fh.read()
else:
priv_key_detail = content
except (IOError, OSError) as exc:
raise OpenSSLObjectError(exc)
if backend == 'pyopenssl':
# First try: try to load with real passphrase (resp. empty string)
# Will work if this is the correct passphrase, or the key is not
# password-protected.
try:
result = crypto.load_privatekey(crypto.FILETYPE_PEM,
priv_key_detail,
to_bytes(passphrase or ''))
except crypto.Error as e:
if len(e.args) > 0 and len(e.args[0]) > 0:
if e.args[0][0][2] in ('bad decrypt', 'bad password read'):
# This happens in case we have the wrong passphrase.
if passphrase is not None:
raise OpenSSLBadPassphraseError('Wrong passphrase provided for private key!')
else:
raise OpenSSLBadPassphraseError('No passphrase provided, but private key is password-protected!')
raise OpenSSLObjectError('Error while deserializing key: {0}'.format(e))
if check_passphrase:
# Next we want to make sure that the key is actually protected by
# a passphrase (in case we did try the empty string before, make
# sure that the key is not protected by the empty string)
try:
crypto.load_privatekey(crypto.FILETYPE_PEM,
priv_key_detail,
to_bytes('y' if passphrase == 'x' else 'x'))
if passphrase is not None:
# Since we can load the key without an exception, the
# key is not password-protected
raise OpenSSLBadPassphraseError('Passphrase provided, but private key is not password-protected!')
except crypto.Error as e:
if passphrase is None and len(e.args) > 0 and len(e.args[0]) > 0:
if e.args[0][0][2] in ('bad decrypt', 'bad password read'):
# The key is obviously protected by the empty string.
# Do not do this at home (if it's possible at all)...
raise OpenSSLBadPassphraseError('No passphrase provided, but private key is password-protected!')
elif backend == 'cryptography':
try:
result = load_pem_private_key(priv_key_detail,
None if passphrase is None else to_bytes(passphrase),
cryptography_backend())
except TypeError:
raise OpenSSLBadPassphraseError('Wrong or empty passphrase provided for private key')
except ValueError:
raise OpenSSLBadPassphraseError('Wrong passphrase provided for private key')
return result
def load_publickey(path=None, content=None, backend=None):
if content is None:
if path is None:
raise OpenSSLObjectError('Must provide either path or content')
try:
with open(path, 'rb') as b_priv_key_fh:
content = b_priv_key_fh.read()
except (IOError, OSError) as exc:
raise OpenSSLObjectError(exc)
if backend == 'cryptography':
try:
return serialization.load_pem_public_key(content, backend=cryptography_backend())
except Exception as e:
raise OpenSSLObjectError('Error while deserializing key: {0}'.format(e))
def load_certificate(path, content=None, backend='cryptography'):
"""Load the specified certificate."""
try:
if content is None:
with open(path, 'rb') as cert_fh:
cert_content = cert_fh.read()
else:
cert_content = content
except (IOError, OSError) as exc:
raise OpenSSLObjectError(exc)
if backend == 'pyopenssl':
return crypto.load_certificate(crypto.FILETYPE_PEM, cert_content)
elif backend == 'cryptography':
try:
return x509.load_pem_x509_certificate(cert_content, cryptography_backend())
except ValueError as exc:
raise OpenSSLObjectError(exc)
def load_certificate_request(path, content=None, backend='cryptography'):
"""Load the specified certificate signing request."""
try:
if content is None:
with open(path, 'rb') as csr_fh:
csr_content = csr_fh.read()
else:
csr_content = content
except (IOError, OSError) as exc:
raise OpenSSLObjectError(exc)
if backend == 'cryptography':
try:
return x509.load_pem_x509_csr(csr_content, cryptography_backend())
except ValueError as exc:
raise OpenSSLObjectError(exc)
def parse_name_field(input_dict, name_field_name=None):
"""Take a dict with key: value or key: list_of_values mappings and return a list of tuples"""
error_str = '{key}' if name_field_name is None else '{key} in {name}'
result = []
for key, value in input_dict.items():
if isinstance(value, list):
for entry in value:
if not isinstance(entry, six.string_types):
raise TypeError(('Values %s must be strings' % error_str).format(key=key, name=name_field_name))
if not entry:
raise ValueError(('Values for %s must not be empty strings' % error_str).format(key=key))
result.append((key, entry))
elif isinstance(value, six.string_types):
if not value:
raise ValueError(('Value for %s must not be an empty string' % error_str).format(key=key))
result.append((key, value))
else:
raise TypeError(('Value for %s must be either a string or a list of strings' % error_str).format(key=key))
return result
def parse_ordered_name_field(input_list, name_field_name):
"""Take a dict with key: value or key: list_of_values mappings and return a list of tuples"""
result = []
for index, entry in enumerate(input_list):
if len(entry) != 1:
raise ValueError(
'Entry #{index} in {name} must be a dictionary with exactly one key-value pair'.format(
name=name_field_name, index=index + 1))
try:
result.extend(parse_name_field(entry, name_field_name=name_field_name))
except (TypeError, ValueError) as exc:
raise ValueError(
'Error while processing entry #{index} in {name}: {error}'.format(
name=name_field_name, index=index + 1, error=exc))
return result
def convert_relative_to_datetime(relative_time_string):
"""Get a datetime.datetime or None from a string in the time format described in sshd_config(5)"""
parsed_result = re.match(
r"^(?P<prefix>[+-])((?P<weeks>\d+)[wW])?((?P<days>\d+)[dD])?((?P<hours>\d+)[hH])?((?P<minutes>\d+)[mM])?((?P<seconds>\d+)[sS]?)?$",
relative_time_string)
if parsed_result is None or len(relative_time_string) == 1:
# not matched or only a single "+" or "-"
return None
offset = datetime.timedelta(0)
if parsed_result.group("weeks") is not None:
offset += datetime.timedelta(weeks=int(parsed_result.group("weeks")))
if parsed_result.group("days") is not None:
offset += datetime.timedelta(days=int(parsed_result.group("days")))
if parsed_result.group("hours") is not None:
offset += datetime.timedelta(hours=int(parsed_result.group("hours")))
if parsed_result.group("minutes") is not None:
offset += datetime.timedelta(
minutes=int(parsed_result.group("minutes")))
if parsed_result.group("seconds") is not None:
offset += datetime.timedelta(
seconds=int(parsed_result.group("seconds")))
if parsed_result.group("prefix") == "+":
return datetime.datetime.utcnow() + offset
else:
return datetime.datetime.utcnow() - offset
def get_relative_time_option(input_string, input_name, backend='cryptography'):
"""Return an absolute timespec if a relative timespec or an ASN1 formatted
string is provided.
The return value will be a datetime object for the cryptography backend,
and a ASN1 formatted string for the pyopenssl backend."""
result = to_native(input_string)
if result is None:
raise OpenSSLObjectError(
'The timespec "%s" for %s is not valid' %
input_string, input_name)
# Relative time
if result.startswith("+") or result.startswith("-"):
result_datetime = convert_relative_to_datetime(result)
if backend == 'pyopenssl':
return result_datetime.strftime("%Y%m%d%H%M%SZ")
elif backend == 'cryptography':
return result_datetime
# Absolute time
if backend == 'cryptography':
for date_fmt in ['%Y%m%d%H%M%SZ', '%Y%m%d%H%MZ', '%Y%m%d%H%M%S%z', '%Y%m%d%H%M%z']:
try:
return datetime.datetime.strptime(result, date_fmt)
except ValueError:
pass
raise OpenSSLObjectError(
'The time spec "%s" for %s is invalid' %
(input_string, input_name)
)
def select_message_digest(digest_string):
digest = None
if digest_string == 'sha256':
digest = hashes.SHA256()
elif digest_string == 'sha384':
digest = hashes.SHA384()
elif digest_string == 'sha512':
digest = hashes.SHA512()
elif digest_string == 'sha1':
digest = hashes.SHA1()
elif digest_string == 'md5':
digest = hashes.MD5()
return digest
@six.add_metaclass(abc.ABCMeta)
class OpenSSLObject(object):
def __init__(self, path, state, force, check_mode):
self.path = path
self.state = state
self.force = force
self.name = os.path.basename(path)
self.changed = False
self.check_mode = check_mode
def check(self, module, perms_required=True):
"""Ensure the resource is in its desired state."""
def _check_state():
return os.path.exists(self.path)
def _check_perms(module):
file_args = module.load_file_common_arguments(module.params)
if module.check_file_absent_if_check_mode(file_args['path']):
return False
return not module.set_fs_attributes_if_different(file_args, False)
if not perms_required:
return _check_state()
return _check_state() and _check_perms(module)
@abc.abstractmethod
def dump(self):
"""Serialize the object into a dictionary."""
pass
@abc.abstractmethod
def generate(self):
"""Generate the resource."""
pass
def remove(self, module):
"""Remove the resource from the filesystem."""
if self.check_mode:
if os.path.exists(self.path):
self.changed = True
return
try:
os.remove(self.path)
self.changed = True
except OSError as exc:
if exc.errno != errno.ENOENT:
raise OpenSSLObjectError(exc)
else:
pass