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.github/workflows/cicd.yml

@@ -28,7 +28,8 @@ name: tests
 env:
   APP_NAME: blti
   CONF_PATH: conf
-  COVERAGE_DJANGO_VERSION: 3.2
+  COVERAGE_DJANGO_VERSION: '4.2'
+  COVERAGE_PYTHON_VERSION: '3.10'
 
 on:
   push:
@@ -42,10 +43,13 @@ on:
 
 jobs:
   test:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
 
     strategy:
       matrix:
+        python-version:
+          - '3.8'
+          - '3.10'
         django-version:
           - '3.2'
           - '4.2'
@@ -54,19 +58,18 @@ jobs:
       - name: Checkout Repo
         uses: actions/checkout@v3
 
-      - name: Setup Python
+      - name: Setup Python ${{ matrix.python-version }}
         uses: actions/setup-python@v4
         with:
-          python-version: '3.8'
+          python-version: ${{ matrix.python-version }}
 
       - name: Install Dependencies
         run: |
-          sudo apt-get install python-dev libxml2-dev libxmlsec1-dev
           python -m pip install --upgrade pip
           pip install -e .
           pip install coverage coveralls==3.3.1
 
-      - name: Upgrade Django Version
+      - name: Upgrade Django ${{ matrix.django-version }}
         run: pip install "Django~=${{ matrix.django-version }}.0"
 
       - name: Setup Django
@@ -90,7 +93,9 @@ jobs:
           coverage run --source=${APP_NAME}/ manage.py test ${APP_NAME}
 
       - name: Report Test Coverage
-        if: matrix.django-version == env.COVERAGE_DJANGO_VERSION
+        if: |
+          matrix.django-version == env.COVERAGE_DJANGO_VERSION &&
+          matrix.python-version == env.COVERAGE_PYTHON_VERSION
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         shell: bash
@@ -101,7 +106,7 @@ jobs:
 
     needs: test
 
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
 
     steps:
       - name: Checkout Repo
@@ -110,7 +115,7 @@ jobs:
       - name: Setup Python
         uses: actions/setup-python@v4
         with:
-          python-version: '3.8'
+          python-version: '3.10'
 
       - name: Publish to PyPi
         uses: uw-it-aca/actions/publish-pypi@main

blti/__init__.py

@@ -1,4 +1,4 @@
-# Copyright 2023 UW-IT, University of Washington
+# Copyright 2024 UW-IT, University of Washington
 # SPDX-License-Identifier: Apache-2.0
 
 

blti/crypto.py

@@ -1,48 +1,55 @@
-# Copyright 2023 UW-IT, University of Washington
+# Copyright 2024 UW-IT, University of Washington
 # SPDX-License-Identifier: Apache-2.0
 
 
-from Crypto.Cipher import AES
+from cryptography.hazmat.primitives import padding
+from cryptography.hazmat.primitives.ciphers import Cipher, modes
+from cryptography.hazmat.primitives.ciphers.algorithms import AES
 from base64 import b64decode, b64encode
 
 
 class aes128cbc(object):
+    """
+    Advanced Encryption Standard object
+
+    For reference:
+    https://cryptography.io/en/latest/hazmat/primitives/symmetric-encryption/
+    """
 
     _key = None
     _iv = None
 
     def __init__(self, key, iv):
-        """
-        Advanced Encryption Standard object
-        """
-        self._bs = 16  # Block size
-
         if key is None:
             raise ValueError('Missing AES key')
-        else:
-            self._key = key
-
         if iv is None:
             raise ValueError('Missing AES initialization vector')
-        else:
-            self._iv = iv
+
+        self._key = key.encode('utf8')
+        self._iv = iv.encode('utf8')
 
     def encrypt(self, msg):
         msg = self._pad(self.str_to_bytes(msg))
-        crypt = AES.new(self._key, AES.MODE_CBC, self._iv)
-        return b64encode(crypt.encrypt(msg)).decode('utf-8')
+        cipher = Cipher(AES(self._key), modes.CBC(self._iv))
+        encryptor = cipher.encryptor()
+        ct = encryptor.update(msg) + encryptor.finalize()
+        return ct
 
     def decrypt(self, msg):
-        msg = b64decode(msg)
-        crypt = AES.new(self._key, AES.MODE_CBC, self._iv)
-        return self._unpad(crypt.decrypt(msg)).decode('utf-8')
+        cipher = Cipher(AES(self._key), modes.CBC(self._iv))
+        decryptor = cipher.decryptor()
+        dct = decryptor.update(msg) + decryptor.finalize()
+        return self._unpad(dct).decode('utf-8')
 
     def _pad(self, s):
-        return s + (self._bs - len(s) % self._bs) * self.str_to_bytes(chr(
-            self._bs - len(s) % self._bs))
+        padder = padding.PKCS7(AES.block_size).padder()
+        pd = padder.update(s) + padder.finalize()
+        return pd
 
     def _unpad(self, s):
-        return s[:-ord(s[len(s)-1:])]
+        unpadder = padding.PKCS7(AES.block_size).unpadder()
+        upd = unpadder.update(s) + unpadder.finalize()
+        return upd
 
     def str_to_bytes(self, s):
         u_type = type(b''.decode('utf8'))

blti/middleware.py

@@ -1,4 +1,4 @@
-# Copyright 2023 UW-IT, University of Washington
+# Copyright 2024 UW-IT, University of Washington
 # SPDX-License-Identifier: Apache-2.0
 
 

blti/models.py

@@ -1,4 +1,4 @@
-# Copyright 2023 UW-IT, University of Washington
+# Copyright 2024 UW-IT, University of Washington
 # SPDX-License-Identifier: Apache-2.0
 
 

blti/performance.py

@@ -1,4 +1,4 @@
-# Copyright 2023 UW-IT, University of Washington
+# Copyright 2024 UW-IT, University of Washington
 # SPDX-License-Identifier: Apache-2.0
 
 

blti/tests.py

@@ -1,4 +1,4 @@
-# Copyright 2023 UW-IT, University of Washington
+# Copyright 2024 UW-IT, University of Washington
 # SPDX-License-Identifier: Apache-2.0
 
 
@@ -210,13 +210,25 @@ def test_get_session(self):
         self.assertEqual(blti.get_session(self.request), {})
 
     def test_encrypt_decrypt_session(self):
+        blti = BLTI()
         data = {'abc': {'key': 123},
                 'xyz': ('LTI provides a framework through which an LMS '
                         'can send some verifiable information about a '
                         'user to a third party.')}
 
-        enc = BLTI()._encrypt_session(data)
-        self.assertEquals(BLTI()._decrypt_session(enc), data)
+        enc = blti._encrypt_session(data)
+        self.assertEquals(blti._decrypt_session(enc), data)
+
+        bdata = b'abcdef'
+        self.assertRaises(TypeError, blti._encrypt_session, bdata)
+
+    def test_missing_key_iv(self):
+        blti = BLTI()
+        with override_settings(BLTI_AES_KEY=None):
+            self.assertRaises(ValueError, blti._encrypt_session, '')
+
+        with override_settings(BLTI_AES_IV=None):
+            self.assertRaises(ValueError, blti._encrypt_session, '')
 
     def test_filter_oauth_params(self):
         data = getattr(settings, 'CANVAS_LTI_V1_LAUNCH_PARAMS', {})

blti/urls.py

@@ -1,4 +1,4 @@
-# Copyright 2023 UW-IT, University of Washington
+# Copyright 2024 UW-IT, University of Washington
 # SPDX-License-Identifier: Apache-2.0
 
 

blti/validators.py

@@ -1,4 +1,4 @@
-# Copyright 2023 UW-IT, University of Washington
+# Copyright 2024 UW-IT, University of Washington
 # SPDX-License-Identifier: Apache-2.0
 
 

blti/views/__init__.py

@@ -1,4 +1,4 @@
-# Copyright 2023 UW-IT, University of Washington
+# Copyright 2024 UW-IT, University of Washington
 # SPDX-License-Identifier: Apache-2.0
 
 

blti/views/develop.py

@@ -1,4 +1,4 @@
-# Copyright 2023 UW-IT, University of Washington
+# Copyright 2024 UW-IT, University of Washington
 # SPDX-License-Identifier: Apache-2.0
 
 

setup.py

@@ -21,14 +21,14 @@
     install_requires=[
         'Django>=3.2,<5',
         'oauthlib',
-        'PyCrypto',
+        'cryptography',
         'mock',
     ],
     license='Apache License, Version 2.0',
     description='A Django Application on which to build IMS BLTI Tool Providers',
     long_description=README,
     url='https://github.com/uw-it-aca/django-blti',
-    author="UW-IT AXDD",
+    author="UW-IT T&LS",
     author_email="[email protected]",
     classifiers=[
         'Environment :: Web Environment',
@@ -37,6 +37,5 @@
         'License :: OSI Approved :: Apache Software License',
         'Operating System :: OS Independent',
         'Programming Language :: Python',
-        'Programming Language :: Python :: 3.8',
     ],
 )