/usr/lib/python2.7/dist-packages/cryptography/hazmat/primitives/asymmetric/rsa.py is in python-cryptography 1.2.3-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 | # This file is dual licensed under the terms of the Apache License, Version
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
# for complete details.
from __future__ import absolute_import, division, print_function
import abc
from fractions import gcd
import six
from cryptography import utils
from cryptography.exceptions import UnsupportedAlgorithm, _Reasons
from cryptography.hazmat.backends.interfaces import RSABackend
@six.add_metaclass(abc.ABCMeta)
class RSAPrivateKey(object):
@abc.abstractmethod
def signer(self, padding, algorithm):
"""
Returns an AsymmetricSignatureContext used for signing data.
"""
@abc.abstractmethod
def decrypt(self, ciphertext, padding):
"""
Decrypts the provided ciphertext.
"""
@abc.abstractproperty
def key_size(self):
"""
The bit length of the public modulus.
"""
@abc.abstractmethod
def public_key(self):
"""
The RSAPublicKey associated with this private key.
"""
@six.add_metaclass(abc.ABCMeta)
class RSAPrivateKeyWithSerialization(RSAPrivateKey):
@abc.abstractmethod
def private_numbers(self):
"""
Returns an RSAPrivateNumbers.
"""
@abc.abstractmethod
def private_bytes(self, encoding, format, encryption_algorithm):
"""
Returns the key serialized as bytes.
"""
@six.add_metaclass(abc.ABCMeta)
class RSAPublicKey(object):
@abc.abstractmethod
def verifier(self, signature, padding, algorithm):
"""
Returns an AsymmetricVerificationContext used for verifying signatures.
"""
@abc.abstractmethod
def encrypt(self, plaintext, padding):
"""
Encrypts the given plaintext.
"""
@abc.abstractproperty
def key_size(self):
"""
The bit length of the public modulus.
"""
@abc.abstractmethod
def public_numbers(self):
"""
Returns an RSAPublicNumbers
"""
@abc.abstractmethod
def public_bytes(self, encoding, format):
"""
Returns the key serialized as bytes.
"""
RSAPublicKeyWithSerialization = RSAPublicKey
def generate_private_key(public_exponent, key_size, backend):
if not isinstance(backend, RSABackend):
raise UnsupportedAlgorithm(
"Backend object does not implement RSABackend.",
_Reasons.BACKEND_MISSING_INTERFACE
)
_verify_rsa_parameters(public_exponent, key_size)
return backend.generate_rsa_private_key(public_exponent, key_size)
def _verify_rsa_parameters(public_exponent, key_size):
if public_exponent < 3:
raise ValueError("public_exponent must be >= 3.")
if public_exponent & 1 == 0:
raise ValueError("public_exponent must be odd.")
if key_size < 512:
raise ValueError("key_size must be at least 512-bits.")
def _check_private_key_components(p, q, private_exponent, dmp1, dmq1, iqmp,
public_exponent, modulus):
if modulus < 3:
raise ValueError("modulus must be >= 3.")
if p >= modulus:
raise ValueError("p must be < modulus.")
if q >= modulus:
raise ValueError("q must be < modulus.")
if dmp1 >= modulus:
raise ValueError("dmp1 must be < modulus.")
if dmq1 >= modulus:
raise ValueError("dmq1 must be < modulus.")
if iqmp >= modulus:
raise ValueError("iqmp must be < modulus.")
if private_exponent >= modulus:
raise ValueError("private_exponent must be < modulus.")
if public_exponent < 3 or public_exponent >= modulus:
raise ValueError("public_exponent must be >= 3 and < modulus.")
if public_exponent & 1 == 0:
raise ValueError("public_exponent must be odd.")
if dmp1 & 1 == 0:
raise ValueError("dmp1 must be odd.")
if dmq1 & 1 == 0:
raise ValueError("dmq1 must be odd.")
if p * q != modulus:
raise ValueError("p*q must equal modulus.")
def _check_public_key_components(e, n):
if n < 3:
raise ValueError("n must be >= 3.")
if e < 3 or e >= n:
raise ValueError("e must be >= 3 and < n.")
if e & 1 == 0:
raise ValueError("e must be odd.")
def _modinv(e, m):
"""
Modular Multiplicative Inverse. Returns x such that: (x*e) mod m == 1
"""
x1, y1, x2, y2 = 1, 0, 0, 1
a, b = e, m
while b > 0:
q, r = divmod(a, b)
xn, yn = x1 - q * x2, y1 - q * y2
a, b, x1, y1, x2, y2 = b, r, x2, y2, xn, yn
return x1 % m
def rsa_crt_iqmp(p, q):
"""
Compute the CRT (q ** -1) % p value from RSA primes p and q.
"""
return _modinv(q, p)
def rsa_crt_dmp1(private_exponent, p):
"""
Compute the CRT private_exponent % (p - 1) value from the RSA
private_exponent and p.
"""
return private_exponent % (p - 1)
def rsa_crt_dmq1(private_exponent, q):
"""
Compute the CRT private_exponent % (q - 1) value from the RSA
private_exponent and q.
"""
return private_exponent % (q - 1)
# Controls the number of iterations rsa_recover_prime_factors will perform
# to obtain the prime factors. Each iteration increments by 2 so the actual
# maximum attempts is half this number.
_MAX_RECOVERY_ATTEMPTS = 1000
def rsa_recover_prime_factors(n, e, d):
"""
Compute factors p and q from the private exponent d. We assume that n has
no more than two factors. This function is adapted from code in PyCrypto.
"""
# See 8.2.2(i) in Handbook of Applied Cryptography.
ktot = d * e - 1
# The quantity d*e-1 is a multiple of phi(n), even,
# and can be represented as t*2^s.
t = ktot
while t % 2 == 0:
t = t // 2
# Cycle through all multiplicative inverses in Zn.
# The algorithm is non-deterministic, but there is a 50% chance
# any candidate a leads to successful factoring.
# See "Digitalized Signatures and Public Key Functions as Intractable
# as Factorization", M. Rabin, 1979
spotted = False
a = 2
while not spotted and a < _MAX_RECOVERY_ATTEMPTS:
k = t
# Cycle through all values a^{t*2^i}=a^k
while k < ktot:
cand = pow(a, k, n)
# Check if a^k is a non-trivial root of unity (mod n)
if cand != 1 and cand != (n - 1) and pow(cand, 2, n) == 1:
# We have found a number such that (cand-1)(cand+1)=0 (mod n).
# Either of the terms divides n.
p = gcd(cand + 1, n)
spotted = True
break
k *= 2
# This value was not any good... let's try another!
a += 2
if not spotted:
raise ValueError("Unable to compute factors p and q from exponent d.")
# Found !
q, r = divmod(n, p)
assert r == 0
return (p, q)
class RSAPrivateNumbers(object):
def __init__(self, p, q, d, dmp1, dmq1, iqmp,
public_numbers):
if (
not isinstance(p, six.integer_types) or
not isinstance(q, six.integer_types) or
not isinstance(d, six.integer_types) or
not isinstance(dmp1, six.integer_types) or
not isinstance(dmq1, six.integer_types) or
not isinstance(iqmp, six.integer_types)
):
raise TypeError(
"RSAPrivateNumbers p, q, d, dmp1, dmq1, iqmp arguments must"
" all be an integers."
)
if not isinstance(public_numbers, RSAPublicNumbers):
raise TypeError(
"RSAPrivateNumbers public_numbers must be an RSAPublicNumbers"
" instance."
)
self._p = p
self._q = q
self._d = d
self._dmp1 = dmp1
self._dmq1 = dmq1
self._iqmp = iqmp
self._public_numbers = public_numbers
p = utils.read_only_property("_p")
q = utils.read_only_property("_q")
d = utils.read_only_property("_d")
dmp1 = utils.read_only_property("_dmp1")
dmq1 = utils.read_only_property("_dmq1")
iqmp = utils.read_only_property("_iqmp")
public_numbers = utils.read_only_property("_public_numbers")
def private_key(self, backend):
return backend.load_rsa_private_numbers(self)
def __eq__(self, other):
if not isinstance(other, RSAPrivateNumbers):
return NotImplemented
return (
self.p == other.p and
self.q == other.q and
self.d == other.d and
self.dmp1 == other.dmp1 and
self.dmq1 == other.dmq1 and
self.iqmp == other.iqmp and
self.public_numbers == other.public_numbers
)
def __ne__(self, other):
return not self == other
def __hash__(self):
return hash((
self.p,
self.q,
self.d,
self.dmp1,
self.dmq1,
self.iqmp,
self.public_numbers,
))
class RSAPublicNumbers(object):
def __init__(self, e, n):
if (
not isinstance(e, six.integer_types) or
not isinstance(n, six.integer_types)
):
raise TypeError("RSAPublicNumbers arguments must be integers.")
self._e = e
self._n = n
e = utils.read_only_property("_e")
n = utils.read_only_property("_n")
def public_key(self, backend):
return backend.load_rsa_public_numbers(self)
def __repr__(self):
return "<RSAPublicNumbers(e={0.e}, n={0.n})>".format(self)
def __eq__(self, other):
if not isinstance(other, RSAPublicNumbers):
return NotImplemented
return self.e == other.e and self.n == other.n
def __ne__(self, other):
return not self == other
def __hash__(self):
return hash((self.e, self.n))
|