diff options
| -rw-r--r-- | cryptography/hazmat/backends/openssl/backend.py | 116 | ||||
| -rw-r--r-- | cryptography/hazmat/backends/openssl/rsa.py | 110 |
2 files changed, 107 insertions, 119 deletions
diff --git a/cryptography/hazmat/backends/openssl/backend.py b/cryptography/hazmat/backends/openssl/backend.py index b3396ea9..5c8d4f4d 100644 --- a/cryptography/hazmat/backends/openssl/backend.py +++ b/cryptography/hazmat/backends/openssl/backend.py @@ -744,122 +744,6 @@ class Backend(object): key = _RSAPublicKey(self, rsa_cdata) return key.encrypt(plaintext, padding) - def _enc_dec_rsa(self, key, data, padding): - if isinstance(padding, PKCS1v15): - padding_enum = self._lib.RSA_PKCS1_PADDING - elif isinstance(padding, OAEP): - padding_enum = self._lib.RSA_PKCS1_OAEP_PADDING - if not isinstance(padding._mgf, MGF1): - raise UnsupportedAlgorithm( - "Only MGF1 is supported by this backend.", - _Reasons.UNSUPPORTED_MGF - ) - - if not isinstance(padding._mgf._algorithm, hashes.SHA1): - raise UnsupportedAlgorithm( - "This backend supports only SHA1 inside MGF1 when " - "using OAEP.", - _Reasons.UNSUPPORTED_HASH - ) - - if padding._label is not None and padding._label != b"": - raise ValueError("This backend does not support OAEP labels.") - - if not isinstance(padding._algorithm, hashes.SHA1): - raise UnsupportedAlgorithm( - "This backend only supports SHA1 when using OAEP.", - _Reasons.UNSUPPORTED_HASH - ) - else: - raise UnsupportedAlgorithm( - "{0} is not supported by this backend.".format( - padding.name - ), - _Reasons.UNSUPPORTED_PADDING - ) - - if self._lib.Cryptography_HAS_PKEY_CTX: - return self._enc_dec_rsa_pkey_ctx(key, data, padding_enum) - else: - return self._enc_dec_rsa_098(key, data, padding_enum) - - def _enc_dec_rsa_pkey_ctx(self, key, data, padding_enum): - evp_pkey = key._evp_pkey - - if isinstance(key, _RSAPublicKey): - init = self._lib.EVP_PKEY_encrypt_init - crypt = self._lib.Cryptography_EVP_PKEY_encrypt - else: - init = self._lib.EVP_PKEY_decrypt_init - crypt = self._lib.Cryptography_EVP_PKEY_decrypt - - pkey_ctx = self._lib.EVP_PKEY_CTX_new( - evp_pkey, self._ffi.NULL - ) - assert pkey_ctx != self._ffi.NULL - pkey_ctx = self._ffi.gc(pkey_ctx, self._lib.EVP_PKEY_CTX_free) - res = init(pkey_ctx) - assert res == 1 - res = self._lib.EVP_PKEY_CTX_set_rsa_padding( - pkey_ctx, padding_enum) - assert res > 0 - buf_size = self._lib.EVP_PKEY_size(evp_pkey) - assert buf_size > 0 - outlen = self._ffi.new("size_t *", buf_size) - buf = self._ffi.new("char[]", buf_size) - res = crypt( - pkey_ctx, - buf, - outlen, - data, - len(data) - ) - if res <= 0: - self._handle_rsa_enc_dec_error(key) - - return self._ffi.buffer(buf)[:outlen[0]] - - def _enc_dec_rsa_098(self, key, data, padding_enum): - rsa_cdata = key._rsa_cdata - - if isinstance(key, _RSAPublicKey): - crypt = self._lib.RSA_public_encrypt - else: - crypt = self._lib.RSA_private_decrypt - - key_size = self._lib.RSA_size(rsa_cdata) - assert key_size > 0 - buf = self._ffi.new("unsigned char[]", key_size) - res = crypt( - len(data), - data, - buf, - rsa_cdata, - padding_enum - ) - if res < 0: - self._handle_rsa_enc_dec_error(key) - - return self._ffi.buffer(buf)[:res] - - def _handle_rsa_enc_dec_error(self, key): - errors = self._consume_errors() - assert errors - assert errors[0].lib == self._lib.ERR_LIB_RSA - if isinstance(key, _RSAPublicKey): - assert (errors[0].reason == - self._lib.RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE) - raise ValueError( - "Data too long for key size. Encrypt less data or use a " - "larger key size." - ) - else: - assert ( - errors[0].reason == self._lib.RSA_R_BLOCK_TYPE_IS_NOT_01 or - errors[0].reason == self._lib.RSA_R_BLOCK_TYPE_IS_NOT_02 - ) - raise ValueError("Decryption failed.") - def cmac_algorithm_supported(self, algorithm): return ( self._lib.Cryptography_HAS_CMAC == 1 diff --git a/cryptography/hazmat/backends/openssl/rsa.py b/cryptography/hazmat/backends/openssl/rsa.py index a62a89f4..6f28c541 100644 --- a/cryptography/hazmat/backends/openssl/rsa.py +++ b/cryptography/hazmat/backends/openssl/rsa.py @@ -22,7 +22,7 @@ from cryptography.exceptions import ( from cryptography.hazmat.primitives import hashes, interfaces from cryptography.hazmat.primitives.asymmetric import rsa from cryptography.hazmat.primitives.asymmetric.padding import ( - MGF1, PKCS1v15, PSS + MGF1, OAEP, PKCS1v15, PSS ) from cryptography.hazmat.primitives.interfaces import ( RSAPrivateKeyWithNumbers, RSAPublicKeyWithNumbers @@ -45,6 +45,110 @@ def _get_rsa_pss_salt_length(pss, key_size, digest_size): return salt +def _enc_dec_rsa(backend, key, data, padding): + if isinstance(padding, PKCS1v15): + padding_enum = backend._lib.RSA_PKCS1_PADDING + elif isinstance(padding, OAEP): + padding_enum = backend._lib.RSA_PKCS1_OAEP_PADDING + if not isinstance(padding._mgf, MGF1): + raise UnsupportedAlgorithm( + "Only MGF1 is supported by this backend.", + _Reasons.UNSUPPORTED_MGF + ) + + if not isinstance(padding._mgf._algorithm, hashes.SHA1): + raise UnsupportedAlgorithm( + "This backend supports only SHA1 inside MGF1 when " + "using OAEP.", + _Reasons.UNSUPPORTED_HASH + ) + + if padding._label is not None and padding._label != b"": + raise ValueError("This backend does not support OAEP labels.") + + if not isinstance(padding._algorithm, hashes.SHA1): + raise UnsupportedAlgorithm( + "This backend only supports SHA1 when using OAEP.", + _Reasons.UNSUPPORTED_HASH + ) + else: + raise UnsupportedAlgorithm( + "{0} is not supported by this backend.".format( + padding.name + ), + _Reasons.UNSUPPORTED_PADDING + ) + + if backend._lib.Cryptography_HAS_PKEY_CTX: + return _enc_dec_rsa_pkey_ctx(backend, key, data, padding_enum) + else: + return _enc_dec_rsa_098(backend, key, data, padding_enum) + + +def _enc_dec_rsa_pkey_ctx(backend, key, data, padding_enum): + if isinstance(key, _RSAPublicKey): + init = backend._lib.EVP_PKEY_encrypt_init + crypt = backend._lib.Cryptography_EVP_PKEY_encrypt + else: + init = backend._lib.EVP_PKEY_decrypt_init + crypt = backend._lib.Cryptography_EVP_PKEY_decrypt + + pkey_ctx = backend._lib.EVP_PKEY_CTX_new( + key._evp_pkey, backend._ffi.NULL + ) + assert pkey_ctx != backend._ffi.NULL + pkey_ctx = backend._ffi.gc(pkey_ctx, backend._lib.EVP_PKEY_CTX_free) + res = init(pkey_ctx) + assert res == 1 + res = backend._lib.EVP_PKEY_CTX_set_rsa_padding( + pkey_ctx, padding_enum) + assert res > 0 + buf_size = backend._lib.EVP_PKEY_size(key._evp_pkey) + assert buf_size > 0 + outlen = backend._ffi.new("size_t *", buf_size) + buf = backend._ffi.new("char[]", buf_size) + res = crypt(pkey_ctx, buf, outlen, data, len(data)) + if res <= 0: + _handle_rsa_enc_dec_error(backend, key) + + return backend._ffi.buffer(buf)[:outlen[0]] + + +def _enc_dec_rsa_098(backend, key, data, padding_enum): + if isinstance(key, _RSAPublicKey): + crypt = backend._lib.RSA_public_encrypt + else: + crypt = backend._lib.RSA_private_decrypt + + key_size = backend._lib.RSA_size(key._rsa_cdata) + assert key_size > 0 + buf = backend._ffi.new("unsigned char[]", key_size) + res = crypt(len(data), data, buf, key._rsa_cdata, padding_enum) + if res < 0: + _handle_rsa_enc_dec_error(backend, key) + + return backend._ffi.buffer(buf)[:res] + + +def _handle_rsa_enc_dec_error(backend, key): + errors = backend._consume_errors() + assert errors + assert errors[0].lib == backend._lib.ERR_LIB_RSA + if isinstance(key, _RSAPublicKey): + assert (errors[0].reason == + backend._lib.RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE) + raise ValueError( + "Data too long for key size. Encrypt less data or use a " + "larger key size." + ) + else: + assert ( + errors[0].reason == backend._lib.RSA_R_BLOCK_TYPE_IS_NOT_01 or + errors[0].reason == backend._lib.RSA_R_BLOCK_TYPE_IS_NOT_02 + ) + raise ValueError("Decryption failed.") + + @utils.register_interface(interfaces.AsymmetricSignatureContext) class _RSASignatureContext(object): def __init__(self, backend, private_key, padding, algorithm): @@ -436,7 +540,7 @@ class _RSAPrivateKey(object): if key_size_bytes != len(ciphertext): raise ValueError("Ciphertext length must be equal to key size.") - return self._backend._enc_dec_rsa(self, ciphertext, padding) + return _enc_dec_rsa(self._backend, self, ciphertext, padding) def public_key(self): ctx = self._backend._lib.RSA_new() @@ -490,7 +594,7 @@ class _RSAPublicKey(object): ) def encrypt(self, plaintext, padding): - return self._backend._enc_dec_rsa(self, plaintext, padding) + return _enc_dec_rsa(self._backend, self, plaintext, padding) def public_numbers(self): return rsa.RSAPublicNumbers( |