def encrypt_str(self, content, key, salt, salt_explicit):
# return the encrypted content prepended with the
# gcm tag and salt_explicit
cipher = Cipher(algorithms.AES(key),
modes.GCM(initialization_vector=self._bulid_iv(salt, salt_explicit)),
backend=default_backend()
).encryptor()
ciphertext = cipher.update(content) + cipher.finalize()
return struct.pack('!q16s', salt_explicit, cipher.tag) + ciphertext
python类GCM的实例源码
def decrypt_str(self, content, key, salt):
# content contains the gcm tag and salt_explicit in plaintext
if len(content) < 24:
raise CryptoException("truncated content")
salt_explicit, gcm_tag = struct.unpack_from('!q16s', content)
cipher = Cipher(algorithms.AES(key),
modes.GCM(initialization_vector=self._bulid_iv(salt, salt_explicit), tag=gcm_tag),
backend=default_backend()
).decryptor()
return cipher.update(content[24:]) + cipher.finalize()
def test_aes_gcm_full(s):
iv_new = os.urandom(16)
cipher_gcm_full = Cipher(algorithms.AES(rawkey), modes.GCM(iv_new),
backend=_default_backend)
encryptor = cipher_gcm_full.encryptor()
r = encryptor.update(s) + encryptor.finalize()
def initialization(self, key):
key = base64.urlsafe_b64decode(key)
k = key[:16]
iv = key[16:28]
cipher = Cipher(algorithms.AES(k), modes.GCM(iv),
backend=default_backend())
self._decryptor = cipher.decryptor()
self._encryptor = cipher.encryptor()
self._last_packet = b""
pushbullet.py 文件源码
项目：Intruder-detector-with-Raspberry-Pi-and-Pushbullet
作者: DeligenceTechnologies
项目源码
文件源码
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def _decrypt_data(self, data):
assert self._encryption_key
from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.hazmat.backends import default_backend
from binascii import a2b_base64
key = self._encryption_key
encoded_message = a2b_base64(data)
version = encoded_message[0:1]
tag = encoded_message[1:17]
initialization_vector = encoded_message[17:29]
encrypted_message = encoded_message[29:]
if version != b"1":
raise Exception("Invalid Version")
cipher = Cipher(algorithms.AES(key),
modes.GCM(initialization_vector, tag),
backend=default_backend())
decryptor = cipher.decryptor()
decrypted = decryptor.update(encrypted_message) + decryptor.finalize()
decrypted = decrypted.decode()
return(decrypted)
pushbullet.py 文件源码
项目：Intruder-detector-with-Raspberry-Pi-and-Pushbullet
作者: DeligenceTechnologies
项目源码
文件源码
阅读 24
收藏 0
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def _decrypt_data(self, data):
assert self._encryption_key
from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.hazmat.backends import default_backend
from binascii import a2b_base64
key = self._encryption_key
encoded_message = a2b_base64(data)
version = encoded_message[0:1]
tag = encoded_message[1:17]
initialization_vector = encoded_message[17:29]
encrypted_message = encoded_message[29:]
if version != b"1":
raise Exception("Invalid Version")
cipher = Cipher(algorithms.AES(key),
modes.GCM(initialization_vector, tag),
backend=default_backend())
decryptor = cipher.decryptor()
decrypted = decryptor.update(encrypted_message) + decryptor.finalize()
decrypted = decrypted.decode()
return(decrypted)
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
block_byte_size = self._block_size // 8
tag_buf = self._backend._ffi.new(
"unsigned char[]", block_byte_size
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
block_byte_size, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
block_byte_size = self._block_size // 8
tag_buf = self._backend._ffi.new(
"unsigned char[]", block_byte_size
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
block_byte_size, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size_bytes)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
tag_buf = self._backend._ffi.new(
"unsigned char[]", self._block_size_bytes
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
self._block_size_bytes, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
block_byte_size = self._block_size // 8
tag_buf = self._backend._ffi.new(
"unsigned char[]", block_byte_size
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
block_byte_size, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
block_byte_size = self._block_size // 8
tag_buf = self._backend._ffi.new(
"unsigned char[]", block_byte_size
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
block_byte_size, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
block_byte_size = self._block_size // 8
tag_buf = self._backend._ffi.new(
"unsigned char[]", block_byte_size
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
block_byte_size, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
block_byte_size = self._block_size // 8
tag_buf = self._backend._ffi.new(
"unsigned char[]", block_byte_size
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
block_byte_size, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
block_byte_size = self._block_size // 8
tag_buf = self._backend._ffi.new(
"unsigned char[]", block_byte_size
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
block_byte_size, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
block_byte_size = self._block_size // 8
tag_buf = self._backend._ffi.new(
"unsigned char[]", block_byte_size
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
block_byte_size, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
block_byte_size = self._block_size // 8
tag_buf = self._backend._ffi.new(
"unsigned char[]", block_byte_size
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
block_byte_size, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
block_byte_size = self._block_size // 8
tag_buf = self._backend._ffi.new(
"unsigned char[]", block_byte_size
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
block_byte_size, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
if (
self._operation == self._DECRYPT and
isinstance(self._mode, modes.ModeWithAuthenticationTag) and
self.tag is None
):
raise ValueError(
"Authentication tag must be provided when decrypting."
)
buf = self._backend._ffi.new("unsigned char[]", self._block_size_bytes)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0]._lib_reason_match(
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0]._lib_reason_match(
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
tag_buf = self._backend._ffi.new(
"unsigned char[]", self._block_size_bytes
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
self._block_size_bytes, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
if (
self._operation == self._DECRYPT and
isinstance(self._mode, modes.ModeWithAuthenticationTag) and
self.tag is None
):
raise ValueError(
"Authentication tag must be provided when decrypting."
)
buf = self._backend._ffi.new("unsigned char[]", self._block_size_bytes)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0]._lib_reason_match(
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0]._lib_reason_match(
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
tag_buf = self._backend._ffi.new(
"unsigned char[]", self._block_size_bytes
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_AEAD_GET_TAG,
self._block_size_bytes, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
def finalize(self):
# OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
# appears to have a bug where you must make at least one call to update
# even if you are only using authenticate_additional_data or the
# GCM tag will be wrong. An (empty) call to update resolves this
# and is harmless for all other versions of OpenSSL.
if isinstance(self._mode, modes.GCM):
self.update(b"")
buf = self._backend._ffi.new("unsigned char[]", self._block_size)
outlen = self._backend._ffi.new("int *")
res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
if res == 0:
errors = self._backend._consume_errors()
if not errors and isinstance(self._mode, modes.GCM):
raise InvalidTag
self._backend.openssl_assert(
errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
) or errors[0][1:] == (
self._backend._lib.ERR_LIB_EVP,
self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
)
)
raise ValueError(
"The length of the provided data is not a multiple of "
"the block length."
)
if (isinstance(self._mode, modes.GCM) and
self._operation == self._ENCRYPT):
block_byte_size = self._block_size // 8
tag_buf = self._backend._ffi.new(
"unsigned char[]", block_byte_size
)
res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
block_byte_size, tag_buf
)
self._backend.openssl_assert(res != 0)
self._tag = self._backend._ffi.buffer(tag_buf)[:]
res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
self._backend.openssl_assert(res == 1)
return self._backend._ffi.buffer(buf)[:outlen[0]]
