Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.10/site-packages/cryptography/hazmat/backends/openssl/backend.py: 45%

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 

136 return self.hash_supported(algorithm) 

137 

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

139 if self._fips_enabled: 

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

141 # FIPS 140-3. 

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

143 return False 

144 

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

146 

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

148 return self.hmac_supported(algorithm) 

149 

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

151 return rust_openssl.capture_error_stack() 

152 

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

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

155 return False 

156 

157 return isinstance( 

158 algorithm, 

159 ( 

160 hashes.SHA1, 

161 hashes.SHA224, 

162 hashes.SHA256, 

163 hashes.SHA384, 

164 hashes.SHA512, 

165 ), 

166 ) 

167 

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

169 if isinstance(padding, PKCS1v15): 

170 return True 

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

172 # SHA1 is permissible in MGF1 in FIPS even when SHA1 is blocked 

173 # as signature algorithm. 

174 if self._fips_enabled and isinstance( 

175 padding._mgf._algorithm, hashes.SHA1 

176 ): 

177 return True 

178 else: 

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

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

181 return self._oaep_hash_supported( 

182 padding._mgf._algorithm 

183 ) and self._oaep_hash_supported(padding._algorithm) 

184 else: 

185 return False 

186 

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

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

189 return False 

190 else: 

191 return self.rsa_padding_supported(padding) 

192 

193 def dsa_supported(self) -> bool: 

194 return ( 

195 not rust_openssl.CRYPTOGRAPHY_IS_BORINGSSL 

196 and not self._fips_enabled 

197 ) 

198 

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

200 if not self.dsa_supported(): 

201 return False 

202 return self.signature_hash_supported(algorithm) 

203 

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

205 return self.cipher_supported( 

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

207 ) 

208 

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

210 if self._fips_enabled and not isinstance( 

211 curve, self._fips_ecdh_curves 

212 ): 

213 return False 

214 

215 return rust_openssl.ec.curve_supported(curve) 

216 

217 def elliptic_curve_signature_algorithm_supported( 

218 self, 

219 signature_algorithm: ec.EllipticCurveSignatureAlgorithm, 

220 curve: ec.EllipticCurve, 

221 ) -> bool: 

222 # We only support ECDSA right now. 

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

224 return False 

225 

226 return self.elliptic_curve_supported(curve) and ( 

227 isinstance(signature_algorithm.algorithm, asym_utils.Prehashed) 

228 or self.hash_supported(signature_algorithm.algorithm) 

229 ) 

230 

231 def elliptic_curve_exchange_algorithm_supported( 

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

233 ) -> bool: 

234 return self.elliptic_curve_supported(curve) and isinstance( 

235 algorithm, ec.ECDH 

236 ) 

237 

238 def dh_supported(self) -> bool: 

239 return not rust_openssl.CRYPTOGRAPHY_IS_BORINGSSL 

240 

241 def dh_x942_serialization_supported(self) -> bool: 

242 return self._lib.Cryptography_HAS_EVP_PKEY_DHX == 1 

243 

244 def x25519_supported(self) -> bool: 

245 if self._fips_enabled: 

246 return False 

247 return True 

248 

249 def x448_supported(self) -> bool: 

250 if self._fips_enabled: 

251 return False 

252 return ( 

253 not rust_openssl.CRYPTOGRAPHY_IS_LIBRESSL 

254 and not rust_openssl.CRYPTOGRAPHY_IS_BORINGSSL 

255 ) 

256 

257 def ed25519_supported(self) -> bool: 

258 if self._fips_enabled: 

259 return False 

260 return True 

261 

262 def ed448_supported(self) -> bool: 

263 if self._fips_enabled: 

264 return False 

265 return ( 

266 not rust_openssl.CRYPTOGRAPHY_IS_LIBRESSL 

267 and not rust_openssl.CRYPTOGRAPHY_IS_BORINGSSL 

268 ) 

269 

270 def ecdsa_deterministic_supported(self) -> bool: 

271 return ( 

272 rust_openssl.CRYPTOGRAPHY_OPENSSL_320_OR_GREATER 

273 and not self._fips_enabled 

274 ) 

275 

276 def poly1305_supported(self) -> bool: 

277 if self._fips_enabled: 

278 return False 

279 return True 

280 

281 def pkcs7_supported(self) -> bool: 

282 return not rust_openssl.CRYPTOGRAPHY_IS_BORINGSSL 

283 

284 

285backend = Backend()