1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
# Copyright (c) 2014-2023 by Ron Frederick <ronf@timeheart.net> and others.
#
# This program and the accompanying materials are made available under
# the terms of the Eclipse Public License v2.0 which accompanies this
# distribution and is available at:
#
# http://www.eclipse.org/legal/epl-2.0/
#
# This program may also be made available under the following secondary
# licenses when the conditions for such availability set forth in the
# Eclipse Public License v2.0 are satisfied:
#
# GNU General Public License, Version 2.0, or any later versions of
# that license
#
# SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-or-later
#
# Contributors:
# Ron Frederick - initial implementation, API, and documentation
"""A shim around PyCA for RSA public and private keys"""
from typing import Optional, cast
from cryptography.exceptions import InvalidSignature
from cryptography.hazmat.primitives.asymmetric.padding import MGF1, OAEP
from cryptography.hazmat.primitives.asymmetric.padding import PKCS1v15
from cryptography.hazmat.primitives.asymmetric import rsa
from .misc import CryptoKey, PyCAKey, hashes
# Short variable names are used here, matching names in the spec
# pylint: disable=invalid-name
class _RSAKey(CryptoKey):
"""Base class for shim around PyCA for RSA keys"""
def __init__(self, pyca_key: PyCAKey, pub: rsa.RSAPublicNumbers,
priv: Optional[rsa.RSAPrivateNumbers] = None):
super().__init__(pyca_key)
self._pub = pub
self._priv = priv
@property
def n(self) -> int:
"""Return the RSA public modulus"""
return self._pub.n
@property
def e(self) -> int:
"""Return the RSA public exponent"""
return self._pub.e
@property
def d(self) -> Optional[int]:
"""Return the RSA private exponent"""
return self._priv.d if self._priv else None
@property
def p(self) -> Optional[int]:
"""Return the RSA first private prime"""
return self._priv.p if self._priv else None
@property
def q(self) -> Optional[int]:
"""Return the RSA second private prime"""
return self._priv.q if self._priv else None
@property
def dmp1(self) -> Optional[int]:
"""Return d modulo p-1"""
return self._priv.dmp1 if self._priv else None
@property
def dmq1(self) -> Optional[int]:
"""Return q modulo p-1"""
return self._priv.dmq1 if self._priv else None
@property
def iqmp(self) -> Optional[int]:
"""Return the inverse of q modulo p"""
return self._priv.iqmp if self._priv else None
class RSAPrivateKey(_RSAKey):
"""A shim around PyCA for RSA private keys"""
@classmethod
def construct(cls, n: int, e: int, d: int, p: int, q: int,
dmp1: int, dmq1: int, iqmp: int,
skip_validation: bool) -> 'RSAPrivateKey':
"""Construct an RSA private key"""
pub = rsa.RSAPublicNumbers(e, n)
priv = rsa.RSAPrivateNumbers(p, q, d, dmp1, dmq1, iqmp, pub)
priv_key = priv.private_key(
unsafe_skip_rsa_key_validation=skip_validation)
return cls(priv_key, pub, priv)
@classmethod
def generate(cls, key_size: int, exponent: int) -> 'RSAPrivateKey':
"""Generate a new RSA private key"""
priv_key = rsa.generate_private_key(exponent, key_size)
priv = priv_key.private_numbers()
pub = priv.public_numbers
return cls(priv_key, pub, priv)
def decrypt(self, data: bytes, hash_name: str) -> Optional[bytes]:
"""Decrypt a block of data"""
try:
hash_alg = hashes[hash_name]()
priv_key = cast('rsa.RSAPrivateKey', self.pyca_key)
return priv_key.decrypt(data, OAEP(MGF1(hash_alg), hash_alg, None))
except ValueError:
return None
def sign(self, data: bytes, hash_name: str = '') -> bytes:
"""Sign a block of data"""
priv_key = cast('rsa.RSAPrivateKey', self.pyca_key)
return priv_key.sign(data, PKCS1v15(), hashes[hash_name]())
class RSAPublicKey(_RSAKey):
"""A shim around PyCA for RSA public keys"""
@classmethod
def construct(cls, n: int, e: int) -> 'RSAPublicKey':
"""Construct an RSA public key"""
pub = rsa.RSAPublicNumbers(e, n)
pub_key = pub.public_key()
return cls(pub_key, pub)
def encrypt(self, data: bytes, hash_name: str) -> Optional[bytes]:
"""Encrypt a block of data"""
try:
hash_alg = hashes[hash_name]()
pub_key = cast('rsa.RSAPublicKey', self.pyca_key)
return pub_key.encrypt(data, OAEP(MGF1(hash_alg), hash_alg, None))
except ValueError:
return None
def verify(self, data: bytes, sig: bytes, hash_name: str = '') -> bool:
"""Verify the signature on a block of data"""
try:
pub_key = cast('rsa.RSAPublicKey', self.pyca_key)
pub_key.verify(sig, data, PKCS1v15(), hashes[hash_name]())
return True
except InvalidSignature:
return False
|
