Updated for Python 3 compatibility.

setup.py

@@ -26,7 +26,7 @@ def read(fname):
     include_package_data = True,
     package_data = {},
     install_requires = [
-        'pycrypto>=2.0.1',
+        'pycrypto>=2.0.1,six',
     ],
     classifiers = [
         'Environment :: Web Environment',

tests/tests.py

@@ -3,6 +3,8 @@
 
 import datetime
 
+import six
+
 from django.http import HttpResponseNotFound
 from django.template.defaultfilters import slugify
 from django.test import TestCase
@@ -23,7 +25,7 @@ class UnfriendlyTests(TestCase):
     urls = 'tests.urls'
 
     def setUp(self):
-        self.juice = 'Lorem ipsum dolor sit amet'
+        self.juice = six.b('Lorem ipsum dolor sit amet')
 
     def test_encryption(self):
         """
@@ -86,6 +88,18 @@ def test_obfuscate_filter(self):
         })
         self.assertEqual(view_url, obfuscated_url)
 
+    def test_obfuscate_long_filter(self):
+        """
+        Test the obfuscate filter.
+        """
+        test_url = reverse('unfriendly-test-long')
+        obfuscated_url = obfuscate(test_url)
+        view_url = reverse('unfriendly-deobfuscate', kwargs={
+            'key': encrypt(test_url, settings.UNFRIENDLY_SECRET,
+                           settings.UNFRIENDLY_IV),
+        })
+        self.assertEqual(view_url, obfuscated_url)
+
     def test_obfuscate_filter_with_juice(self):
         """
         Test the obfuscate filter.
@@ -142,6 +156,18 @@ def test_deobfuscate_view(self):
 
         self.assertEqual(test_response.content, obfuscated_response.content)
 
+    def test_deobfuscate_long_view(self):
+        """
+        Test the deobfuscate view.
+        """
+        test_url = reverse('unfriendly-test-long')
+        obfuscated_url = obfuscate(test_url)
+
+        test_response = self.client.get(test_url)
+        obfuscated_response = self.client.get(obfuscated_url)
+
+        self.assertEqual(test_response.content, obfuscated_response.content)
+
     def test_deobfuscate_view_with_juice(self):
         """
         Test the deobfuscate view with seo juice.

tests/urls.py

@@ -8,5 +8,6 @@
 
 urlpatterns = [
     url(r'^test-view/$', test_view, name='unfriendly-test'),
+    url(r'^' + 'test-view' * 20 + '/$', test_view, name='unfriendly-test-long'),
     url(r'^', include('unfriendly.urls')),
 ]

unfriendly/__init__.py

@@ -1,5 +1,5 @@
 # -*- coding: utf-8 -*-
 """Main django-unfriendly package."""
 
-VERSION = (0, 5, 0)
+VERSION = (0, 6, 'dev')
 __version__ = '.'.join([str(x) for x in VERSION])

unfriendly/utils.py

@@ -2,9 +2,12 @@
 """Various encryption utilites."""
 
 import base64
+import binascii
 import struct
 import zlib
 
+import six
+
 from Crypto.Cipher import AES
 
 
@@ -23,6 +26,15 @@ def _lazysecret(secret, blocksize=32, padding='}'):
         return secret + (blocksize - len(secret)) * padding
     return secret
 
+def _crc(plaintext):
+    """Generates crc32. Modulo keep the value within int range."""
+    if not isinstance(plaintext, six.binary_type):
+        plaintext = six.b(plaintext)
+    return (zlib.crc32(plaintext) % 2147483647) & 0xffffffff
+
+def _pack_crc(plaintext):
+    """Packs plaintext crc32 as binary data."""
+    return struct.pack('i', _crc(plaintext))
 
 def encrypt(plaintext, secret, inital_vector, checksum=True, lazy=True):
     """Encrypts plaintext with secret
@@ -33,15 +45,21 @@ def encrypt(plaintext, secret, inital_vector, checksum=True, lazy=True):
     checksum       - attach crc32 byte encoded (default: True)
     returns ciphertext
     """
+    if not isinstance(plaintext, six.binary_type):
+        plaintext = six.b(plaintext)
 
     secret = _lazysecret(secret) if lazy else secret
     encobj = AES.new(secret, AES.MODE_CFB, inital_vector)
 
     if checksum:
-        plaintext += base64.urlsafe_b64encode(
-            struct.pack("i", zlib.crc32(plaintext)))
+        packed = _pack_crc(plaintext)
+        plaintext += base64.urlsafe_b64encode(packed)
 
-    return base64.urlsafe_b64encode(encobj.encrypt(plaintext)).replace('=', '')
+    encoded = base64.urlsafe_b64encode(encobj.encrypt(plaintext))
+    if isinstance(plaintext, six.binary_type):
+        encoded = encoded.decode()
+
+    return encoded.replace('=', '')
 
 
 def decrypt(ciphertext, secret, inital_vector, checksum=True, lazy=True):
@@ -53,23 +71,22 @@ def decrypt(ciphertext, secret, inital_vector, checksum=True, lazy=True):
     checksum       - verify crc32 byte encoded checksum (default: True)
     returns plaintext
     """
-
     secret = _lazysecret(secret) if lazy else secret
     encobj = AES.new(secret, AES.MODE_CFB, inital_vector)
     try:
         plaintext = encobj.decrypt(base64.urlsafe_b64decode(
             ciphertext + ('=' * (len(ciphertext) % 4))))
-    except TypeError:
+    except (TypeError, binascii.Error):
         raise InvalidKeyError("invalid key")
 
     if checksum:
         try:
             crc, plaintext = (base64.urlsafe_b64decode(
                 plaintext[-8:]), plaintext[:-8])
-        except TypeError:
+        except (TypeError, binascii.Error):
             raise CheckSumError("checksum mismatch")
 
-        if not crc == struct.pack("i", zlib.crc32(plaintext)):
+        if not crc == _pack_crc(plaintext):
             raise CheckSumError("checksum mismatch")
 
     return plaintext

unfriendly/views.py

@@ -1,17 +1,19 @@
 # -*- coding: utf-8 -*-
 """Django view handlers."""
 
-from urllib import unquote
-from urlparse import urlparse
-
 from django.http import HttpResponseNotFound
 
+try:
+    from urllib.parse import unquote, urlparse
+except ImportError:
+    from urllib import unquote
+    from urlparse import urlparse
+
 try:
     from django.urls import Resolver404, resolve
 except ImportError:
     from django.core.urlresolvers  import Resolver404, resolve
 
-
 from unfriendly import settings
 from unfriendly.utils import CheckSumError, InvalidKeyError, decrypt
 
@@ -29,6 +31,11 @@ def deobfuscate(request, key, juice=None):
     except (CheckSumError, InvalidKeyError):
         return HttpResponseNotFound()
 
+    try:
+        url = url.decode('utf-8')
+    except UnicodeDecodeError:
+        return HttpResponseNotFound()
+
     url_parts = urlparse(unquote(url))
     path = url_parts.path
     query = url_parts.query