From 17879128bd568d4a36ff01da9d6d0bc41bd909d7 Mon Sep 17 00:00:00 2001
From: Basak Akan <basak.akan@tum.de>
Date: Fri, 6 Oct 2023 15:28:41 +0200
Subject: [PATCH] add custom exception

---
 .../exception/LtiEmailAlreadyInUseException.java       | 10 ++++++++++
 .../www1/artemis/security/lti/Lti13LaunchFilter.java   |  6 +++---
 .../artemis/service/connectors/lti/LtiService.java     |  3 ++-
 3 files changed, 15 insertions(+), 4 deletions(-)
 create mode 100644 src/main/java/de/tum/in/www1/artemis/exception/LtiEmailAlreadyInUseException.java

diff --git a/src/main/java/de/tum/in/www1/artemis/exception/LtiEmailAlreadyInUseException.java b/src/main/java/de/tum/in/www1/artemis/exception/LtiEmailAlreadyInUseException.java
new file mode 100644
index 000000000000..e5414b5bdc8c
--- /dev/null
+++ b/src/main/java/de/tum/in/www1/artemis/exception/LtiEmailAlreadyInUseException.java
@@ -0,0 +1,10 @@
+package de.tum.in.www1.artemis.exception;
+
+import org.springframework.security.authentication.AuthenticationServiceException;
+
+public class LtiEmailAlreadyInUseException extends AuthenticationServiceException {
+
+    public LtiEmailAlreadyInUseException() {
+        super("Email address is already in use by Artemis. Please login again to access Artemis content.");
+    }
+}
diff --git a/src/main/java/de/tum/in/www1/artemis/security/lti/Lti13LaunchFilter.java b/src/main/java/de/tum/in/www1/artemis/security/lti/Lti13LaunchFilter.java
index 303862f593e3..2b590a5ea542 100644
--- a/src/main/java/de/tum/in/www1/artemis/security/lti/Lti13LaunchFilter.java
+++ b/src/main/java/de/tum/in/www1/artemis/security/lti/Lti13LaunchFilter.java
@@ -11,7 +11,6 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.context.annotation.Profile;
-import org.springframework.security.authentication.InternalAuthenticationServiceException;
 import org.springframework.security.oauth2.core.OAuth2AuthenticationException;
 import org.springframework.security.oauth2.core.oidc.OidcIdToken;
 import org.springframework.security.oauth2.core.oidc.user.OidcUser;
@@ -21,6 +20,7 @@
 import org.springframework.web.util.UriComponentsBuilder;
 
 import de.tum.in.www1.artemis.domain.lti.Claims;
+import de.tum.in.www1.artemis.exception.LtiEmailAlreadyInUseException;
 import de.tum.in.www1.artemis.service.connectors.lti.Lti13Service;
 import net.minidev.json.JSONObject;
 import uk.ac.ox.ctl.lti13.security.oauth2.client.lti.authentication.OidcAuthenticationToken;
@@ -71,8 +71,8 @@ protected void doFilterInternal(HttpServletRequest request, HttpServletResponse
             log.error("Error during LTI 1.3 launch request: {}", ex.getMessage());
             response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, "LTI 1.3 Launch failed");
         }
-        catch (InternalAuthenticationServiceException ex) {
-            response.sendError(HttpServletResponse.SC_UNAUTHORIZED, ex.getMessage());
+        catch (LtiEmailAlreadyInUseException ex) {
+            response.sendError(HttpServletResponse.SC_UNAUTHORIZED, "LTI 1.3 user authentication failed");
         }
     }
 
diff --git a/src/main/java/de/tum/in/www1/artemis/service/connectors/lti/LtiService.java b/src/main/java/de/tum/in/www1/artemis/service/connectors/lti/LtiService.java
index b8819ce035c8..53899b59f1bd 100644
--- a/src/main/java/de/tum/in/www1/artemis/service/connectors/lti/LtiService.java
+++ b/src/main/java/de/tum/in/www1/artemis/service/connectors/lti/LtiService.java
@@ -28,6 +28,7 @@
 import de.tum.in.www1.artemis.domain.Exercise;
 import de.tum.in.www1.artemis.domain.User;
 import de.tum.in.www1.artemis.exception.ArtemisAuthenticationException;
+import de.tum.in.www1.artemis.exception.LtiEmailAlreadyInUseException;
 import de.tum.in.www1.artemis.repository.UserRepository;
 import de.tum.in.www1.artemis.security.ArtemisAuthenticationProvider;
 import de.tum.in.www1.artemis.security.Role;
@@ -100,7 +101,7 @@ public void authenticateLtiUser(String email, String username, String firstName,
         // 2. Case: Lookup user with the LTI email address and make sure it's not in use
         final var usernameLookupByEmail = artemisAuthenticationProvider.getUsernameForEmail(email);
         if (usernameLookupByEmail.isPresent()) {
-            throw new InternalAuthenticationServiceException("Please login again as " + usernameLookupByEmail);
+            throw new LtiEmailAlreadyInUseException();
         }
 
         // 3. Case: Create new user if an existing user is not required