refactor encrypt; add cfb1 and cfb8 modes

.travis.yml

@@ -15,6 +15,8 @@ script:
   - pep8 .
   - python tests/test.py -c tests/table.json
   - python tests/test.py -c tests/aes.json
+  - python tests/test.py -c tests/aes-cfb1.json
+  - python tests/test.py -c tests/aes-cfb8.json
   - python tests/test.py -c tests/rc4-md5.json
   - python tests/test.py -c tests/salsa20.json
   - python tests/test.py -c tests/server-multi-ports.json

setup.py

@@ -12,7 +12,7 @@ setup(
     author='clowwindy',
     author_email='clowwindy42@gmail.com',
     url='https://github.com/clowwindy/shadowsocks',
-    packages=['shadowsocks'],
+    packages=['shadowsocks', 'shadowsocks.crypto'],
     package_data={
         'shadowsocks': ['README.rst', 'LICENSE']
     },

shadowsocks/crypto/__init__.py

@@ -0,0 +1,21 @@
+#!/usr/bin/env python
+
+# Copyright (c) 2014 clowwindy
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.

shadowsocks/crypto/ctypes_openssl.py

@@ -0,0 +1,100 @@
+#!/usr/bin/env python
+
+# Copyright (c) 2014 clowwindy
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+import logging
+
+__all__ = ['ciphers']
+
+loaded = False
+
+
+def load_openssl():
+    global loaded, libcrypto, CDLL, c_char_p, c_int, c_long, byref,\
+        create_string_buffer, c_void_p, buf
+    from ctypes import CDLL, c_char_p, c_int, c_long, byref,\
+        create_string_buffer, c_void_p
+    from ctypes.util import find_library
+    libcrypto_path = find_library('crypto')
+    logging.info('loading libcrypto from %s', libcrypto_path)
+    libcrypto = CDLL(libcrypto_path)
+    libcrypto.EVP_get_cipherbyname.restype = c_void_p
+    libcrypto.EVP_CIPHER_CTX_new.restype = c_void_p
+    libcrypto.EVP_CIPHER_CTX_new.argtypes = (c_void_p, c_void_p, c_char_p,
+                                             c_char_p)
+
+    libcrypto.EVP_CipherInit_ex.argtypes = (c_void_p, c_void_p, c_char_p,
+                                            c_char_p, c_char_p, c_int)
+
+    libcrypto.EVP_CipherUpdate.argtypes = (c_void_p, c_void_p, c_void_p,
+                                           c_char_p, c_int)
+
+    libcrypto.EVP_CIPHER_CTX_cleanup.argtypes = (c_void_p,)
+    libcrypto.EVP_CIPHER_CTX_free.argtypes = (c_void_p,)
+
+    buf = create_string_buffer(65536)
+    loaded = True
+
+
+class CtypesCrypto(object):
+    def __init__(self, cipher_name, key, iv, op):
+        if not loaded:
+            load_openssl()
+        self._ctx = None
+        cipher = libcrypto.EVP_get_cipherbyname(cipher_name)
+        if not cipher:
+            raise Exception('cipher %s not found in libcrypto' % cipher_name)
+        key_ptr = c_char_p(key)
+        iv_ptr = c_char_p(iv)
+        self._ctx = libcrypto.EVP_CIPHER_CTX_new(cipher, None,
+                                                 key_ptr, iv_ptr)
+        if not self._ctx:
+            raise Exception('can not create cipher context')
+        r = libcrypto.EVP_CipherInit_ex(self._ctx, cipher, None,
+                                        key_ptr, iv_ptr, c_int(op))
+        if not r:
+            self.clean()
+            raise Exception('can not initialize cipher context')
+
+    def update(self, data):
+        cipher_out_len = c_long(0)
+        libcrypto.EVP_CipherUpdate(self._ctx, byref(buf),
+                                   byref(cipher_out_len), c_char_p(data),
+                                   len(data))
+        return buf.raw[:cipher_out_len.value]
+
+    def __del__(self):
+        self.clean()
+
+    def clean(self):
+        if self._ctx:
+            libcrypto.EVP_CIPHER_CTX_cleanup(self._ctx)
+            libcrypto.EVP_CIPHER_CTX_free(self._ctx)
+
+
+ciphers = {
+    'aes-128-cfb8': (16, 16, CtypesCrypto),
+    'aes-192-cfb8': (24, 16, CtypesCrypto),
+    'aes-256-cfb8': (32, 16, CtypesCrypto),
+    'aes-128-cfb1': (16, 16, CtypesCrypto),
+    'aes-192-cfb1': (24, 16, CtypesCrypto),
+    'aes-256-cfb1': (32, 16, CtypesCrypto),
+}

shadowsocks/crypto/m2.py

@@ -0,0 +1,66 @@
+#!/usr/bin/env python
+
+# Copyright (c) 2014 clowwindy
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+import sys
+import logging
+
+__all__ = ['ciphers']
+
+has_m2 = True
+try:
+    __import__('M2Crypto')
+except ImportError:
+    has_m2 = False
+
+
+def create_cipher(alg, key, iv, op, key_as_bytes=0, d=None, salt=None, i=1,
+                  padding=1):
+
+    import M2Crypto.EVP
+    return M2Crypto.EVP.Cipher('rc4', key, iv, op, key_as_bytes=0,
+                               d='md5', salt=None, i=1, padding=1)
+
+
+def err(alg, key, iv, op, key_as_bytes=0, d=None, salt=None, i=1, padding=1):
+    logging.error(('M2Crypto is required to use %s, please run'
+                   ' `apt-get install python-m2crypto`') % alg)
+    sys.exit(1)
+
+
+if not has_m2:
+    create_cipher = err
+
+ciphers = {
+    'aes-128-cfb': (16, 16, create_cipher),
+    'aes-192-cfb': (24, 16, create_cipher),
+    'aes-256-cfb': (32, 16, create_cipher),
+    'bf-cfb': (16, 8, create_cipher),
+    'camellia-128-cfb': (16, 16, create_cipher),
+    'camellia-192-cfb': (24, 16, create_cipher),
+    'camellia-256-cfb': (32, 16, create_cipher),
+    'cast5-cfb': (16, 8, create_cipher),
+    'des-cfb': (8, 8, create_cipher),
+    'idea-cfb': (16, 8, create_cipher),
+    'rc2-cfb': (16, 8, create_cipher),
+    'rc4': (16, 0, create_cipher),
+    'seed-cfb': (16, 16, create_cipher),
+}

shadowsocks/encrypt_rc4_md5.py → shadowsocks/crypto/rc4_md5.py

@@ -20,9 +20,13 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
+
 import hashlib
 
 
+__all__ = ['ciphers']
+
+
 def create_cipher(alg, key, iv, op, key_as_bytes=0, d=None, salt=None,
                   i=1, padding=1):
     md5 = hashlib.md5()
@@ -33,3 +37,8 @@ def create_cipher(alg, key, iv, op, key_as_bytes=0, d=None, salt=None,
     import M2Crypto.EVP
     return M2Crypto.EVP.Cipher('rc4', rc4_key, '', op, key_as_bytes=0,
                                d='md5', salt=None, i=1, padding=1)
+
+
+ciphers = {
+    'rc4-md5': (16, 16, create_cipher),
+}

shadowsocks/encrypt_salsa20.py → shadowsocks/crypto/salsa20_ctr.py

@@ -149,5 +149,10 @@ def test():
     assert ''.join(results) == plain
 
 
+ciphers = {
+    'salsa20-ctr': (32, 8, Salsa20Cipher),
+}
+
+
 if __name__ == '__main__':
     test()

shadowsocks/encrypt.py

@@ -26,8 +26,19 @@ import hashlib
 import string
 import struct
 import logging
-import encrypt_salsa20
-import encrypt_rc4_md5
+import crypto.m2
+import crypto.rc4_md5
+import crypto.salsa20_ctr
+import crypto.ctypes_openssl
+
+
+method_supported = {
+}
+
+method_supported.update(crypto.m2.ciphers)
+method_supported.update(crypto.rc4_md5.ciphers)
+method_supported.update(crypto.salsa20_ctr.ciphers)
+method_supported.update(crypto.ctypes_openssl.ciphers)
 
 
 def random_string(length):
@@ -57,13 +68,6 @@ def get_table(key):
 def init_table(key, method=None):
     if method is not None and method == 'table':
         method = None
-    if method:
-        try:
-            __import__('M2Crypto')
-        except ImportError:
-            logging.error(('M2Crypto is required to use %s, please run'
-                           ' `apt-get install python-m2crypto`') % method)
-            sys.exit(1)
     if not method:
         if key in cached_tables:
             return cached_tables[key]
@@ -103,25 +107,6 @@ def EVP_BytesToKey(password, key_len, iv_len):
     return (key, iv)
 
 
-method_supported = {
-    'aes-128-cfb': (16, 16),
-    'aes-192-cfb': (24, 16),
-    'aes-256-cfb': (32, 16),
-    'bf-cfb': (16, 8),
-    'camellia-128-cfb': (16, 16),
-    'camellia-192-cfb': (24, 16),
-    'camellia-256-cfb': (32, 16),
-    'cast5-cfb': (16, 8),
-    'des-cfb': (8, 8),
-    'idea-cfb': (16, 8),
-    'rc2-cfb': (16, 8),
-    'rc4': (16, 0),
-    'rc4-md5': (16, 16),
-    'seed-cfb': (16, 16),
-    'salsa20-ctr': (32, 8),
-}
-
-
 class Encryptor(object):
     def __init__(self, key, method=None):
         if method == 'table':
@@ -138,7 +123,7 @@ class Encryptor(object):
             self.encrypt_table, self.decrypt_table = init_table(key)
             self.cipher = None
 
-    def get_cipher_len(self, method):
+    def get_cipher_param(self, method):
         method = method.lower()
         m = method_supported.get(method, None)
         return m
@@ -149,7 +134,7 @@ class Encryptor(object):
     def get_cipher(self, password, method, op, iv=None):
         password = password.encode('utf-8')
         method = method.lower()
-        m = self.get_cipher_len(method)
+        m = self.get_cipher_param(method)
         if m:
             key, iv_ = EVP_BytesToKey(password, m[0], m[1])
             if iv is None:
@@ -158,15 +143,7 @@ class Encryptor(object):
             if op == 1:
                 # this iv is for cipher not decipher
                 self.cipher_iv = iv[:m[1]]
-            if method == 'salsa20-ctr':
-                return encrypt_salsa20.Salsa20Cipher(method, key, iv, op)
-            elif method == 'rc4-md5':
-                return encrypt_rc4_md5.create_cipher(method, key, iv, op)
-            else:
-                import M2Crypto.EVP
-                return M2Crypto.EVP.Cipher(method.replace('-', '_'), key, iv,
-                                           op, key_as_bytes=0, d='md5',
-                                           salt=None, i=1, padding=1)
+            return m[2](method, key, iv, op)
 
         logging.error('method %s not supported' % method)
         sys.exit(1)
@@ -190,7 +167,7 @@ class Encryptor(object):
             return string.translate(buf, self.decrypt_table)
         else:
             if self.decipher is None:
-                decipher_iv_len = self.get_cipher_len(self.method)[1]
+                decipher_iv_len = self.get_cipher_param(self.method)[1]
                 decipher_iv = buf[:decipher_iv_len]
                 self.decipher = self.get_cipher(self.key, self.method, 0,
                                                 iv=decipher_iv)
@@ -210,10 +187,9 @@ def encrypt_all(password, method, op, data):
         else:
             return string.translate(data, decrypt_table)
     else:
-        import M2Crypto.EVP
         result = []
         method = method.lower()
-        (key_len, iv_len) = method_supported[method]
+        (key_len, iv_len, m) = method_supported[method]
         (key, _) = EVP_BytesToKey(password, key_len, iv_len)
         if op:
             iv = random_string(iv_len)
@@ -221,13 +197,6 @@ def encrypt_all(password, method, op, data):
         else:
             iv = data[:iv_len]
             data = data[iv_len:]
-        if method == 'salsa20-ctr':
-            cipher = encrypt_salsa20.Salsa20Cipher(method, key, iv, op)
-        elif method == 'rc4-md5':
-            cipher = encrypt_rc4_md5.create_cipher(method, key, iv, op)
-        else:
-            cipher = M2Crypto.EVP.Cipher(method.replace('-', '_'), key, iv,
-                                         op, key_as_bytes=0, d='md5',
-                                         salt=None, i=1, padding=1)
+        cipher = m(method, key, iv, op)
         result.append(cipher.update(data))
         return ''.join(result)

tests/aes-cfb1.json

@@ -0,0 +1,10 @@
+{
+    "server":"127.0.0.1",
+    "server_port":8388,
+    "local_port":1081,
+    "password":"aes_password",
+    "timeout":60,
+    "method":"aes-256-cfb1",
+    "local_address":"127.0.0.1",
+    "fast_open":false
+}

tests/aes-cfb8.json

@@ -0,0 +1,10 @@
+{
+    "server":"127.0.0.1",
+    "server_port":8388,
+    "local_port":1081,
+    "password":"aes_password",
+    "timeout":60,
+    "method":"aes-256-cfb8",
+    "local_address":"127.0.0.1",
+    "fast_open":false
+}

tests/test.py

@@ -11,8 +11,8 @@ from subprocess import Popen, PIPE
 sys.path.insert(0, './')
 
 if 'salsa20' in sys.argv[-1]:
-    from shadowsocks import encrypt_salsa20
-    encrypt_salsa20.test()
+    from shadowsocks.crypto import salsa20_ctr
+    salsa20_ctr.test()
     print 'encryption test passed'
 
 p1 = Popen(['python', 'shadowsocks/server.py', '-c', sys.argv[-1]], stdin=PIPE,