cipher pylint fixes

src/pyelliptic/cipher.py

@@ -1,5 +1,9 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
+"""
+src/pyelliptic/cipher.py
+========================
+"""
 
 #  Copyright (C) 2011 Yann GUIBET <yannguibet@gmail.com>
 #  See LICENSE for details.
@@ -7,7 +11,8 @@
 from openssl import OpenSSL
 
 
-class Cipher:
+# pylint: disable=redefined-builtin
+class Cipher(object):
     """
     Symmetric encryption
 
@@ -44,30 +49,34 @@ class Cipher:
 
     @staticmethod
     def get_blocksize(ciphername):
+        """This Method returns cipher blocksize"""
         cipher = OpenSSL.get_cipher(ciphername)
         return cipher.get_blocksize()
 
     @staticmethod
     def gen_IV(ciphername):
+        """Generate random initialization vector"""
         cipher = OpenSSL.get_cipher(ciphername)
         return OpenSSL.rand(cipher.get_blocksize())
 
     def update(self, input):
+        """Update result with more data"""
         i = OpenSSL.c_int(0)
         buffer = OpenSSL.malloc(b"", len(input) + self.cipher.get_blocksize())
         inp = OpenSSL.malloc(input, len(input))
         if OpenSSL.EVP_CipherUpdate(self.ctx, OpenSSL.byref(buffer),
                                     OpenSSL.byref(i), inp, len(input)) == 0:
             raise Exception("[OpenSSL] EVP_CipherUpdate FAIL ...")
-        return buffer.raw[0:i.value]
+        return buffer.raw[0:i.value]    # pylint: disable=invalid-slice-index
 
     def final(self):
+        """Returning the final value"""
         i = OpenSSL.c_int(0)
         buffer = OpenSSL.malloc(b"", self.cipher.get_blocksize())
         if (OpenSSL.EVP_CipherFinal_ex(self.ctx, OpenSSL.byref(buffer),
                                        OpenSSL.byref(i))) == 0:
             raise Exception("[OpenSSL] EVP_CipherFinal_ex FAIL ...")
-        return buffer.raw[0:i.value]
+        return buffer.raw[0:i.value]    # pylint: disable=invalid-slice-index
 
     def ciphering(self, input):
         """
@@ -77,6 +86,7 @@ class Cipher:
         return buff + self.final()
 
     def __del__(self):
+        # pylint: disable=protected-access
         if OpenSSL._hexversion > 0x10100000 and not OpenSSL._libreSSL:
             OpenSSL.EVP_CIPHER_CTX_reset(self.ctx)
         else:

src/pyelliptic/hash.py

@@ -27,6 +27,7 @@ def _equals_str(a, b):
 
 
 def equals(a, b):
+    """Compare two strings or bytearrays"""
     if isinstance(a, str):
         return _equals_str(a, b)
     else:
@@ -58,6 +59,7 @@ def hmac_sha512(k, m):
 
 
 def pbkdf2(password, salt=None, i=10000, keylen=64):
+    """Compute the salt, key and the message with pbkdf2"""
     if salt is None:
         salt = OpenSSL.rand(8)
     p_password = OpenSSL.malloc(password, len(password))