Implements basic LTI 1.3

inginious/frontend/app.py

@@ -16,6 +16,7 @@
 from binascii import hexlify
 from pymongo import MongoClient
 from werkzeug.exceptions import InternalServerError
+from flask_caching import Cache
 
 import inginious.frontend.pages.course_admin.utils as course_admin_utils
 import inginious.frontend.pages.taskset_admin.utils as taskset_admin_utils
@@ -87,6 +88,8 @@ def _put_configuration_defaults(config):
     config["SESSION_USE_SIGNER"] = True
     config["PERMANENT_SESSION_LIFETIME"] = config['session_parameters']["timeout"]
     config["SECRET_KEY"] = config['session_parameters']["secret_key"]
+    config["CACHE_TYPE"] = "simple"
+    config["CACHE_DEFAULT_TIMEOUT"] = 600
 
     smtp_conf = config.get('smtp', None)
     if smtp_conf is not None:
@@ -314,6 +317,8 @@ def flask_internalerror(e):
     flask_app.privacy_page = config.get("privacy_page", None)
     flask_app.static_directory = config.get("static_directory", "./static")
     flask_app.webdav_host = config.get("webdav_host", None)
+    cache = Cache(flask_app)
+    flask_app.cache = cache
 
     # Init the mapping of the app
     init_flask_mapping(flask_app)

inginious/frontend/courses.py

@@ -7,8 +7,9 @@
 
 import copy
 import gettext
+import hashlib
 import re
-from typing import List
+from typing import Iterable, List
 
 from inginious.frontend.user_settings.course_user_setting import CourseUserSetting
 from inginious.common.tags import Tag
@@ -18,6 +19,7 @@
 from inginious.frontend.task_dispensers.toc import TableOfContents
 from inginious.frontend.tasksets import _migrate_from_v_0_6
 
+from pylti1p3.tool_config import ToolConfDict
 
 class Course(object):
     """ A course with some modification for users """
@@ -54,7 +56,7 @@ def __init__(self, courseid, content, taskset_factory, task_factory, plugin_mana
         self._allow_preview = self._content.get('allow_preview', False)
         self._is_lti = self._content.get('is_lti', False)
         self._lti_url = self._content.get('lti_url', '')
-        self._lti_keys = self._content.get('lti_keys', {})
+        self._lti_config = self._content.get('lti_config', {})
         self._lti_send_back_grade = self._content.get('lti_send_back_grade', False)
         self._tags = {key: Tag(key, tag_dict, self.gettext) for key, tag_dict in self._content.get("tags", {}).items()}
         self._course_user_setting = {key: CourseUserSetting(key,
@@ -82,7 +84,7 @@ def __init__(self, courseid, content, taskset_factory, task_factory, plugin_mana
             self._groups_student_choice = False
             self._allow_unregister = False
         else:
-            self._lti_keys = {}
+            self._lti_config = {}
             self._lti_url = ''
             self._lti_send_back_grade = False
 
@@ -162,9 +164,28 @@ def is_lti(self):
         """ True if the current course is in LTI mode """
         return self._is_lti
 
-    def lti_keys(self):
-        """ {name: key} for the LTI customers """
-        return self._lti_keys if self._is_lti else {}
+    def lti_config(self):
+        """ LTI Tool config dictionary. Specs are at https://github.com/dmitry-viskov/pylti1.3/blob/master/README.rst?plain=1#L70-L98 """
+        return self._lti_config if self._is_lti else {}
+
+    def lti_tool(self) -> ToolConfDict:
+        """ LTI Tool object. """
+        lti_tool = ToolConfDict(self._lti_config)
+        for iss in self._lti_config:
+            for client_config in self._lti_config[iss]:
+                lti_tool.set_private_key(iss, client_config['private_key'], client_id=client_config['client_id'])
+                lti_tool.set_public_key(iss, client_config['public_key'], client_id=client_config['client_id'])
+        return lti_tool
+
+    def lti_platform_instances_ids(self) -> Iterable[str]:
+        """ Set of LTI Platform instance ids registered for this course. """
+        for iss in self._lti_config:
+            for client_config in self._lti_config[iss]:
+                for deployment_id in client_config['deployment_ids']:
+                    yield '/'.join([iss, client_config['client_id'], deployment_id])
+
+    def lti_keyset_hash(self, issuer: str, client_id: str) -> str:
+        return hashlib.md5((issuer + client_id).encode('utf-8')).digest().hex()
 
     def lti_url(self):
         """ Returns the URL to the external platform the course is hosted on """

inginious/frontend/flask/mapping.py

@@ -25,7 +25,7 @@
 from inginious.frontend.pages.course_register import CourseRegisterPage
 from inginious.frontend.pages.course import CoursePage
 from inginious.frontend.pages.tasks import TaskPage, TaskPageStaticDownload
-from inginious.frontend.pages.lti import LTITaskPage, LTILaunchPage, LTIBindPage, LTIAssetPage, LTILoginPage
+from inginious.frontend.pages.lti import LTITaskPage, LTIBindPage, LTIAssetPage, LTILaunchPage, LTIOIDCLoginPage, LTIJWKSPage, LTILoginPage
 from inginious.frontend.pages.group import GroupPage
 from inginious.frontend.pages.marketplace import MarketplacePage
 from inginious.frontend.pages.marketplace_taskset import MarketplaceTasksetPage
@@ -91,9 +91,12 @@ def init_flask_mapping(flask_app):
                            view_func=BindingsPage.as_view('bindingspage'))
     flask_app.add_url_rule('/preferences/delete', view_func=DeletePage.as_view('deletepage'))
     flask_app.add_url_rule('/preferences/profile', view_func=ProfilePage.as_view('profilepage'))
-    flask_app.add_url_rule('/lti/task', view_func=LTITaskPage.as_view('ltitaskpage'))
-    flask_app.add_url_rule('/lti/<courseid>/<taskid>',
+    flask_app.add_url_rule('/lti/oidc_login/<courseid>',
+                           view_func=LTIOIDCLoginPage.as_view('ltioidcloginpage'))
+    flask_app.add_url_rule('/lti/launch/<courseid>/<taskid>',
                            view_func=LTILaunchPage.as_view('ltilaunchpage'))
+    flask_app.add_url_rule('/lti/jwks/<courseid>/<keyset_hash>', view_func=LTIJWKSPage.as_view('ltijwkspage'))
+    flask_app.add_url_rule('/lti/task', view_func=LTITaskPage.as_view('ltitaskpage'))
     flask_app.add_url_rule('/lti/bind', view_func=LTIBindPage.as_view('ltibindpage'))
     flask_app.add_url_rule('/lti/login', view_func=LTILoginPage.as_view('ltiloginpage'))
     flask_app.add_url_rule('/lti/asset/<path:asset_url>',

inginious/frontend/pages/course_admin/settings.py

@@ -3,6 +3,7 @@
 # This file is part of INGInious. See the LICENSE and the COPYRIGHTS files for
 # more information about the licensing of this file.
 
+import json
 import re
 import flask
 
@@ -11,6 +12,8 @@
 from inginious.frontend.accessible_time import AccessibleTime
 from inginious.frontend.pages.course_admin.utils import INGIniousAdminPage
 
+from pylti1p3.tool_config import ToolConfDict
+from jwcrypto.jwk import JWK  # type: ignore
 
 class CourseSettingsPage(INGIniousAdminPage):
     """ Couse settings """
@@ -82,11 +85,37 @@ def POST_AUTH(self, courseid):  # pylint: disable=arguments-differ
 
         course_content['is_lti'] = 'lti' in data and data['lti'] == "true"
         course_content['lti_url'] = data.get("lti_url", "")
-        course_content['lti_keys'] = dict([x.split(":") for x in data['lti_keys'].splitlines() if x])
 
-        for lti_key in course_content['lti_keys'].keys():
-            if not re.match("^[a-zA-Z0-9]*$", lti_key):
-                errors.append(_("LTI keys must be alphanumerical."))
+        try:
+            lti_config = json.loads(data['lti_config'])
+            assert type(lti_config) is dict, 'Not a JSON object'
+            for iss in lti_config:
+                iss_config = lti_config[iss]
+                assert type(iss_config) is list, f'Issuer {iss} must have a list of client_id configuration'
+                for i, client_config in enumerate(iss_config):
+                    required_keys = {'default', 'client_id', 'auth_login_url', 'auth_token_url', 'key_set_url', 'private_key', 'public_key', 'deployment_ids'}
+                    for key in required_keys:
+                        assert key in client_config, f'Missing {key} in client config {i} of issuer {iss}'
+            tool_conf = ToolConfDict(lti_config)
+            for iss in lti_config:
+                for i, client_config in enumerate(lti_config[iss]):
+                    tool_conf.set_private_key(iss, client_config['private_key'], client_id=client_config['client_id'])
+                    try:
+                        JWK.from_pem(client_config['private_key'].encode('utf-8')).export(private_key=True)  # Checks the private key format
+                    except ValueError:
+                        raise Exception(f"Error in private key of client config {i} of issuer {iss}")
+                    tool_conf.set_public_key(iss, client_config['public_key'], client_id=client_config['client_id'])
+                    try:
+                        JWK.from_pem(client_config['public_key'].encode('utf-8')).export(private_key=False)  # Checks the public key format
+                    except ValueError:
+                        raise Exception(f"Error in public key of client config {i} of issuer {iss}")
+            course_content['lti_config'] = lti_config
+        except json.JSONDecodeError as e:
+            errors.append(_("LTI config couldn't parse as JSON") + ' - ' + str(e))
+        except AssertionError as e:
+            errors.append(_('LTI config is incorrect') + ' - ' + str(e))
+        except Exception as e:
+            errors.append(_('LTI config is incorrect') + ' - ' + str(e))
 
         course_content['lti_send_back_grade'] = 'lti_send_back_grade' in data and data['lti_send_back_grade'] == "true"