Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/cryptography/hazmat/backends/openssl/backend.py: 46%

1# This file is dual licensed under the terms of the Apache License, Version 

2# 2.0, and the BSD License. See the LICENSE file in the root of this repository 

3# for complete details. 

4 

5from __future__ import annotations 

6 

7from cryptography.hazmat.bindings._rust import openssl as rust_openssl 

8from cryptography.hazmat.bindings.openssl import binding 

9from cryptography.hazmat.primitives import hashes 

10from cryptography.hazmat.primitives._asymmetric import AsymmetricPadding 

11from cryptography.hazmat.primitives.asymmetric import ec 

12from cryptography.hazmat.primitives.asymmetric import utils as asym_utils 

13from cryptography.hazmat.primitives.asymmetric.padding import ( 

14 MGF1, 

15 OAEP, 

16 PSS, 

17 PKCS1v15, 

18) 

19from cryptography.hazmat.primitives.ciphers import ( 

20 CipherAlgorithm, 

21) 

22from cryptography.hazmat.primitives.ciphers.algorithms import ( 

23 AES, 

24) 

25from cryptography.hazmat.primitives.ciphers.modes import ( 

26 CBC, 

27 Mode, 

28) 

29 

30 

31class Backend: 

32 """ 

33 OpenSSL API binding interfaces. 

34 """ 

35 

36 name = "openssl" 

37 

38 # TripleDES encryption is disallowed/deprecated throughout 2023 in 

39 # FIPS 140-3. To keep it simple we denylist any use of TripleDES (TDEA). 

40 _fips_ciphers = (AES,) 

41 # Sometimes SHA1 is still permissible. That logic is contained 

42 # within the various *_supported methods. 

43 _fips_hashes = ( 

44 hashes.SHA224, 

45 hashes.SHA256, 

46 hashes.SHA384, 

47 hashes.SHA512, 

48 hashes.SHA512_224, 

49 hashes.SHA512_256, 

50 hashes.SHA3_224, 

51 hashes.SHA3_256, 

52 hashes.SHA3_384, 

53 hashes.SHA3_512, 

54 hashes.SHAKE128, 

55 hashes.SHAKE256, 

56 ) 

57 _fips_ecdh_curves = ( 

58 ec.SECP224R1, 

59 ec.SECP256R1, 

60 ec.SECP384R1, 

61 ec.SECP521R1, 

62 ) 

63 _fips_rsa_min_key_size = 2048 

64 _fips_rsa_min_public_exponent = 65537 

65 _fips_dsa_min_modulus = 1 << 2048 

66 _fips_dh_min_key_size = 2048 

67 _fips_dh_min_modulus = 1 << _fips_dh_min_key_size 

68 

69 def __init__(self) -> None: 

70 self._binding = binding.Binding() 

71 self._ffi = self._binding.ffi 

72 self._lib = self._binding.lib 

73 self._fips_enabled = rust_openssl.is_fips_enabled() 

74 

75 def __repr__(self) -> str: 

76 return ( 

77 f"<OpenSSLBackend(version: {self.openssl_version_text()}, " 

78 f"FIPS: {self._fips_enabled}, " 

79 f"Legacy: {rust_openssl._legacy_provider_loaded})>" 

80 ) 

81 

82 def openssl_assert(self, ok: bool) -> None: 

83 return binding._openssl_assert(ok) 

84 

85 def _enable_fips(self) -> None: 

86 # This function enables FIPS mode for OpenSSL 3.0.0 on installs that 

87 # have the FIPS provider installed properly. 

88 rust_openssl.enable_fips(rust_openssl._providers) 

89 assert rust_openssl.is_fips_enabled() 

90 self._fips_enabled = rust_openssl.is_fips_enabled() 

91 

92 def openssl_version_text(self) -> str: 

93 """ 

94 Friendly string name of the loaded OpenSSL library. This is not 

95 necessarily the same version as it was compiled against. 

96 

97 Example: OpenSSL 3.2.1 30 Jan 2024 

98 """ 

99 return rust_openssl.openssl_version_text() 

100 

101 def openssl_version_number(self) -> int: 

102 return rust_openssl.openssl_version() 

103 

104 def hash_supported(self, algorithm: hashes.HashAlgorithm) -> bool: 

105 if self._fips_enabled and not isinstance(algorithm, self._fips_hashes): 

106 return False 

107 

108 return rust_openssl.hashes.hash_supported(algorithm) 

109 

110 def signature_hash_supported( 

111 self, algorithm: hashes.HashAlgorithm 

112 ) -> bool: 

113 # Dedicated check for hashing algorithm use in message digest for 

114 # signatures, e.g. RSA PKCS#1 v1.5 SHA1 (sha1WithRSAEncryption). 

115 if self._fips_enabled and isinstance(algorithm, hashes.SHA1): 

116 return False 

117 return self.hash_supported(algorithm) 

118 

119 def scrypt_supported(self) -> bool: 

120 if self._fips_enabled: 

121 return False 

122 else: 

123 return hasattr(rust_openssl.kdf.Scrypt, "derive") 

124 

125 def argon2_supported(self) -> bool: 

126 if self._fips_enabled: 

127 return False 

128 else: 

129 return hasattr(rust_openssl.kdf.Argon2id, "derive") 

130 

131 def hmac_supported(self, algorithm: hashes.HashAlgorithm) -> bool: 

132 # FIPS mode still allows SHA1 for HMAC 

133 if self._fips_enabled and isinstance(algorithm, hashes.SHA1): 

134 return True 

135 if rust_openssl.CRYPTOGRAPHY_IS_AWSLC: 

136 return isinstance( 

137 algorithm, 

138 ( 

139 hashes.MD5, 

140 hashes.SHA1, 

141 hashes.SHA224, 

142 hashes.SHA256, 

143 hashes.SHA384, 

144 hashes.SHA512, 

145 hashes.SHA512_224, 

146 hashes.SHA512_256, 

147 ), 

148 ) 

149 return self.hash_supported(algorithm) 

150 

151 def cipher_supported(self, cipher: CipherAlgorithm, mode: Mode) -> bool: 

152 if self._fips_enabled: 

153 # FIPS mode requires AES. TripleDES is disallowed/deprecated in 

154 # FIPS 140-3. 

155 if not isinstance(cipher, self._fips_ciphers): 

156 return False 

157 

158 return rust_openssl.ciphers.cipher_supported(cipher, mode) 

159 

160 def pbkdf2_hmac_supported(self, algorithm: hashes.HashAlgorithm) -> bool: 

161 return self.hmac_supported(algorithm) 

162 

163 def _consume_errors(self) -> list[rust_openssl.OpenSSLError]: 

164 return rust_openssl.capture_error_stack() 

165 

166 def _oaep_hash_supported(self, algorithm: hashes.HashAlgorithm) -> bool: 

167 if self._fips_enabled and isinstance(algorithm, hashes.SHA1): 

168 return False 

169 

170 return isinstance( 

171 algorithm, 

172 ( 

173 hashes.SHA1, 

174 hashes.SHA224, 

175 hashes.SHA256, 

176 hashes.SHA384, 

177 hashes.SHA512, 

178 ), 

179 ) 

180 

181 def rsa_padding_supported(self, padding: AsymmetricPadding) -> bool: 

182 if isinstance(padding, PKCS1v15): 

183 return True 

184 elif isinstance(padding, PSS) and isinstance(padding._mgf, MGF1): 

185 # FIPS 186-4 only allows salt length == digest length for PSS 

186 # It is technically acceptable to set an explicit salt length 

187 # equal to the digest length and this will incorrectly fail, but 

188 # since we don't do that in the tests and this method is 

189 # private, we'll ignore that until we need to do otherwise. 

190 if ( 

191 self._fips_enabled 

192 and padding._salt_length != PSS.DIGEST_LENGTH 

193 ): 

194 return False 

195 return self.hash_supported(padding._mgf._algorithm) 

196 elif isinstance(padding, OAEP) and isinstance(padding._mgf, MGF1): 

197 return self._oaep_hash_supported( 

198 padding._mgf._algorithm 

199 ) and self._oaep_hash_supported(padding._algorithm) 

200 else: 

201 return False 

202 

203 def rsa_encryption_supported(self, padding: AsymmetricPadding) -> bool: 

204 if self._fips_enabled and isinstance(padding, PKCS1v15): 

205 return False 

206 else: 

207 return self.rsa_padding_supported(padding) 

208 

209 def dsa_supported(self) -> bool: 

210 return ( 

211 not rust_openssl.CRYPTOGRAPHY_IS_BORINGSSL 

212 and not self._fips_enabled 

213 ) 

214 

215 def dsa_hash_supported(self, algorithm: hashes.HashAlgorithm) -> bool: 

216 if not self.dsa_supported(): 

217 return False 

218 return self.signature_hash_supported(algorithm) 

219 

220 def cmac_algorithm_supported(self, algorithm) -> bool: 

221 return self.cipher_supported( 

222 algorithm, CBC(b"\x00" * algorithm.block_size) 

223 ) 

224 

225 def elliptic_curve_supported(self, curve: ec.EllipticCurve) -> bool: 

226 if self._fips_enabled and not isinstance( 

227 curve, self._fips_ecdh_curves 

228 ): 

229 return False 

230 

231 return rust_openssl.ec.curve_supported(curve) 

232 

233 def elliptic_curve_signature_algorithm_supported( 

234 self, 

235 signature_algorithm: ec.EllipticCurveSignatureAlgorithm, 

236 curve: ec.EllipticCurve, 

237 ) -> bool: 

238 # We only support ECDSA right now. 

239 if not isinstance(signature_algorithm, ec.ECDSA): 

240 return False 

241 

242 return self.elliptic_curve_supported(curve) and ( 

243 isinstance(signature_algorithm.algorithm, asym_utils.Prehashed) 

244 or self.hash_supported(signature_algorithm.algorithm) 

245 ) 

246 

247 def elliptic_curve_exchange_algorithm_supported( 

248 self, algorithm: ec.ECDH, curve: ec.EllipticCurve 

249 ) -> bool: 

250 return self.elliptic_curve_supported(curve) and isinstance( 

251 algorithm, ec.ECDH 

252 ) 

253 

254 def dh_supported(self) -> bool: 

255 return ( 

256 not rust_openssl.CRYPTOGRAPHY_IS_BORINGSSL 

257 and not rust_openssl.CRYPTOGRAPHY_IS_AWSLC 

258 ) 

259 

260 def dh_x942_serialization_supported(self) -> bool: 

261 return self._lib.Cryptography_HAS_EVP_PKEY_DHX == 1 

262 

263 def x25519_supported(self) -> bool: 

264 return not self._fips_enabled 

265 

266 def x448_supported(self) -> bool: 

267 if self._fips_enabled: 

268 return False 

269 return ( 

270 not rust_openssl.CRYPTOGRAPHY_IS_LIBRESSL 

271 and not rust_openssl.CRYPTOGRAPHY_IS_BORINGSSL 

272 and not rust_openssl.CRYPTOGRAPHY_IS_AWSLC 

273 ) 

274 

275 def mlkem_supported(self) -> bool: 

276 return ( 

277 rust_openssl.CRYPTOGRAPHY_IS_AWSLC 

278 or rust_openssl.CRYPTOGRAPHY_IS_BORINGSSL 

279 ) 

280 

281 def mldsa_supported(self) -> bool: 

282 return ( 

283 rust_openssl.CRYPTOGRAPHY_IS_AWSLC 

284 or rust_openssl.CRYPTOGRAPHY_IS_BORINGSSL 

285 ) 

286 

287 def ed25519_supported(self) -> bool: 

288 return True 

289 

290 def ed448_supported(self) -> bool: 

291 return ( 

292 not rust_openssl.CRYPTOGRAPHY_IS_LIBRESSL 

293 and not rust_openssl.CRYPTOGRAPHY_IS_BORINGSSL 

294 and not rust_openssl.CRYPTOGRAPHY_IS_AWSLC 

295 ) 

296 

297 def ecdsa_deterministic_supported(self) -> bool: 

298 return ( 

299 rust_openssl.CRYPTOGRAPHY_OPENSSL_320_OR_GREATER 

300 and not self._fips_enabled 

301 ) 

302 

303 def poly1305_supported(self) -> bool: 

304 return not self._fips_enabled 

305 

306 def pkcs7_supported(self) -> bool: 

307 return True 

308 

309 

310backend = Backend()