diff options
-rw-r--r-- | cryptography/bindings/openssl/api.py | 8 | ||||
-rw-r--r-- | cryptography/primitives/block/ciphers.py | 24 | ||||
-rw-r--r-- | docs/primitives/symmetric-encryption.rst | 17 | ||||
-rw-r--r-- | tests/primitives/test_ciphers.py | 17 | ||||
-rw-r--r-- | tests/primitives/test_nist.py | 90 |
5 files changed, 154 insertions, 2 deletions
diff --git a/cryptography/bindings/openssl/api.py b/cryptography/bindings/openssl/api.py index 7d189d62..3d92c144 100644 --- a/cryptography/bindings/openssl/api.py +++ b/cryptography/bindings/openssl/api.py @@ -19,7 +19,7 @@ import sys import cffi from cryptography.primitives import interfaces -from cryptography.primitives.block.ciphers import AES, Camellia +from cryptography.primitives.block.ciphers import AES, Camellia, TripleDES from cryptography.primitives.block.modes import CBC, CTR, ECB, OFB, CFB @@ -135,6 +135,12 @@ class API(object): mode_cls, GetCipherByName("{cipher.name}-{cipher.key_size}-{mode.name}") ) + for mode_cls in [CBC, CFB, OFB]: + self.register_cipher_adapter( + TripleDES, + mode_cls, + GetCipherByName("des-ede3-{mode.name}") + ) def create_block_cipher_context(self, cipher, mode): ctx = self.lib.EVP_CIPHER_CTX_new() diff --git a/cryptography/primitives/block/ciphers.py b/cryptography/primitives/block/ciphers.py index 4ac150a4..4143b89d 100644 --- a/cryptography/primitives/block/ciphers.py +++ b/cryptography/primitives/block/ciphers.py @@ -52,3 +52,27 @@ class Camellia(object): @property def key_size(self): return len(self.key) * 8 + + +class TripleDES(object): + name = "3DES" + block_size = 64 + key_sizes = frozenset([64, 128, 192]) + + def __init__(self, key): + super(TripleDES, self).__init__() + if len(key) == 8: + key += key + key + elif len(key) == 16: + key += key[:8] + self.key = key + + # Verify that the key size matches the expected key size + if self.key_size not in self.key_sizes: + raise ValueError("Invalid key size ({0}) for {1}".format( + self.key_size, self.name + )) + + @property + def key_size(self): + return len(self.key) * 8 diff --git a/docs/primitives/symmetric-encryption.rst b/docs/primitives/symmetric-encryption.rst index 7899e67d..96bd68f0 100644 --- a/docs/primitives/symmetric-encryption.rst +++ b/docs/primitives/symmetric-encryption.rst @@ -61,6 +61,23 @@ Ciphers This must be kept secret. +.. class:: cryptography.primitives.block.ciphers.TripleDES(key) + + Triple DES (Data Encryption Standard), sometimes refered to as 3DES, is a + block cipher standardized by NIST. Triple DES has known cryptoanalytic + flaws, however none of them currently enable a practical attack. + Nonetheless, Triples DES is not reccomended for new applications because it + is incredibly slow; old applications should consider moving away from it. + + :param bytes key: The secret key, either ``64``, ``128``, or ``192`` bits + (note that DES functionally uses ``56``, ``112``, or + ``168`` bits of the key, there is a parity byte in each + component of the key), in some materials these are + referred to as being up to three separate keys (each + ``56`` bits long), they can simply be concatenated to + produce the full key. This must be kept secret. + + Modes ~~~~~ diff --git a/tests/primitives/test_ciphers.py b/tests/primitives/test_ciphers.py index 27d35850..17fcdbaf 100644 --- a/tests/primitives/test_ciphers.py +++ b/tests/primitives/test_ciphers.py @@ -17,7 +17,7 @@ import binascii import pytest -from cryptography.primitives.block.ciphers import AES, Camellia +from cryptography.primitives.block.ciphers import AES, Camellia, TripleDES class TestAES(object): @@ -48,3 +48,18 @@ class TestCamellia(object): def test_invalid_key_size(self): with pytest.raises(ValueError): Camellia(binascii.unhexlify(b"0" * 12)) + + +class TestTripleDES(object): + @pytest.mark.parametrize("key", [ + b"0" * 16, + b"0" * 32, + b"0" * 48, + ]) + def test_key_size(self, key): + cipher = TripleDES(binascii.unhexlify(key)) + assert cipher.key_size == 192 + + def test_invalid_key_size(self): + with pytest.raises(ValueError): + TripleDES(binascii.unhexlify(b"0" * 12)) diff --git a/tests/primitives/test_nist.py b/tests/primitives/test_nist.py index d97b207b..2a32d1bc 100644 --- a/tests/primitives/test_nist.py +++ b/tests/primitives/test_nist.py @@ -164,3 +164,93 @@ class TestAES_CFB(object): lambda key, iv: ciphers.AES(binascii.unhexlify(key)), lambda key, iv: modes.CFB(binascii.unhexlify(iv)), ) + + +class TestTripleDES_CBC(object): + test_KAT = generate_encrypt_test( + lambda path: load_nist_vectors_from_file(path, "ENCRYPT"), + os.path.join("3DES", "KAT"), + [ + "TCBCinvperm.rsp", + "TCBCpermop.rsp", + "TCBCsubtab.rsp", + "TCBCvarkey.rsp", + "TCBCvartext.rsp", + ], + lambda keys, iv: ciphers.TripleDES(binascii.unhexlify(keys)), + lambda keys, iv: modes.CBC(binascii.unhexlify(iv)), + ) + + test_MMT = generate_encrypt_test( + lambda path: load_nist_vectors_from_file(path, "ENCRYPT"), + os.path.join("3DES", "MMT"), + [ + "TCBCMMT1.rsp", + "TCBCMMT2.rsp", + "TCBCMMT3.rsp", + ], + lambda key1, key2, key3, iv: ( + ciphers.TripleDES(binascii.unhexlify(key1 + key2 + key3)) + ), + lambda key1, key2, key3, iv: modes.CBC(binascii.unhexlify(iv)), + ) + + +class TestTripleDES_OFB(object): + test_KAT = generate_encrypt_test( + lambda path: load_nist_vectors_from_file(path, "ENCRYPT"), + os.path.join("3DES", "KAT"), + [ + "TOFBpermop.rsp", + "TOFBsubtab.rsp", + "TOFBvarkey.rsp", + "TOFBvartext.rsp", + "TOFBinvperm.rsp", + ], + lambda keys, iv: ciphers.TripleDES(binascii.unhexlify(keys)), + lambda keys, iv: modes.OFB(binascii.unhexlify(iv)), + ) + + test_MMT = generate_encrypt_test( + lambda path: load_nist_vectors_from_file(path, "ENCRYPT"), + os.path.join("3DES", "MMT"), + [ + "TOFBMMT1.rsp", + "TOFBMMT2.rsp", + "TOFBMMT3.rsp", + ], + lambda key1, key2, key3, iv: ( + ciphers.TripleDES(binascii.unhexlify(key1 + key2 + key3)) + ), + lambda key1, key2, key3, iv: modes.OFB(binascii.unhexlify(iv)), + ) + + +class TestTripleDES_CFB(object): + test_KAT = generate_encrypt_test( + lambda path: load_nist_vectors_from_file(path, "ENCRYPT"), + os.path.join("3DES", "KAT"), + [ + "TCFB64invperm.rsp", + "TCFB64permop.rsp", + "TCFB64subtab.rsp", + "TCFB64varkey.rsp", + "TCFB64vartext.rsp", + ], + lambda keys, iv: ciphers.TripleDES(binascii.unhexlify(keys)), + lambda keys, iv: modes.CFB(binascii.unhexlify(iv)), + ) + + test_MMT = generate_encrypt_test( + lambda path: load_nist_vectors_from_file(path, "ENCRYPT"), + os.path.join("3DES", "MMT"), + [ + "TCFB64MMT1.rsp", + "TCFB64MMT2.rsp", + "TCFB64MMT3.rsp", + ], + lambda key1, key2, key3, iv: ( + ciphers.TripleDES(binascii.unhexlify(key1 + key2 + key3)) + ), + lambda key1, key2, key3, iv: modes.CFB(binascii.unhexlify(iv)), + ) |