Offline tokens created in Keycloak 14 or earlier will not work on Keycloak 25

closes #31224

Signed-off-by: mposolda <mposolda@gmail.com>

core/src/main/java/org/keycloak/representations/IDToken.java

@@ -172,7 +172,7 @@ public class IDToken extends JsonWebToken {
     @Deprecated
     @JsonIgnore
     public String getSessionState() {
-        return sessionId;
+        return getSessionId();
     }
 
     public String getAccessTokenHash() {

core/src/main/java/org/keycloak/representations/RefreshToken.java

@@ -53,4 +53,11 @@ public class RefreshToken extends AccessToken {
     public TokenCategory getCategory() {
         return TokenCategory.INTERNAL;
     }
+
+    @Override
+    public String getSessionId() {
+        String sessionId = super.getSessionId();
+        // Fallback as offline tokens created in Keycloak 14 or earlier have only the "session_state" claim, but not "sid"
+        return sessionId != null ? sessionId : (String) getOtherClaims().get(IDToken.SESSION_STATE);
+    }
 }

testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/oauth/OfflineTokenMigrationTest.java

@@ -0,0 +1,127 @@
+/*
+ * Copyright 2024 Red Hat, Inc. and/or its affiliates
+ *  and other contributors as indicated by the @author tags.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ */
+
+package org.keycloak.testsuite.oauth;
+
+import java.io.Serializable;
+import java.util.Map;
+import java.util.function.BiFunction;
+
+import org.jboss.arquillian.graphene.page.Page;
+import org.junit.Assert;
+import org.junit.Test;
+import org.keycloak.OAuth2Constants;
+import org.keycloak.crypto.SignatureProvider;
+import org.keycloak.crypto.SignatureSignerContext;
+import org.keycloak.jose.jws.JWSBuilder;
+import org.keycloak.jose.jws.JWSInput;
+import org.keycloak.models.KeycloakSession;
+import org.keycloak.representations.AccessToken;
+import org.keycloak.representations.IDToken;
+import org.keycloak.representations.RefreshToken;
+import org.keycloak.representations.idm.RealmRepresentation;
+import org.keycloak.testsuite.AbstractTestRealmKeycloakTest;
+import org.keycloak.testsuite.pages.LoginPage;
+import org.keycloak.testsuite.runonserver.FetchOnServer;
+import org.keycloak.testsuite.runonserver.FetchOnServerWrapper;
+import org.keycloak.testsuite.util.OAuthClient;
+import org.keycloak.util.JsonSerialization;
+
+/**
+ * Test for simulating token refresh with the offline tokens created in older Keycloak versions.
+ *
+ * Keycloak supports refresh of the offline tokens, which were created in older Keycloak versions than current Keycloak version. But
+ * testing real migration is sometimes hard to achieve as it requires running of the old Keycloak server, which is sometimes not feasible.
+ *
+ * This test just simulates the refresh with the old offline-token by manually converting offline-token to the offline-token format, which was used by the specified old Keycloak version
+ *
+ * @author <a href="mailto:mposolda@redhat.com">Marek Posolda</a>
+ */
+public class OfflineTokenMigrationTest extends AbstractTestRealmKeycloakTest {
+
+    @Page
+    protected LoginPage loginPage;
+
+    @Override
+    public void configureTestRealm(RealmRepresentation testRealm) {
+
+    }
+
+    // Issue 31224
+    // Test refresh with the offline-token created in Keycloak 14 works
+    @Test
+    public void testOfflineTokenMigrationFromKeycloak14() throws Exception {
+        OfflineTokenConverter convertOfflineTokenToKeycloak14Format = (session, oldOfflineToken) -> {
+            try {
+                RefreshToken refreshToken = session.tokens().decode(oldOfflineToken, RefreshToken.class);
+                String sessionId = refreshToken.getSessionId();
+                String signatureAlgorithm = new JWSInput(oldOfflineToken).getHeader().getAlgorithm().toString();
+
+                Map<String, String> asMap = JsonSerialization.readValue(JsonSerialization.writeValueAsString(refreshToken), Map.class);
+                asMap.remove(IDToken.SESSION_ID);
+                asMap.put(IDToken.SESSION_STATE, sessionId);
+
+                SignatureProvider signatureProvider = session.getProvider(SignatureProvider.class, signatureAlgorithm);
+                SignatureSignerContext signer = signatureProvider.signer();
+
+                String type = "JWT";
+                return new JWSBuilder().type(type).jsonContent(asMap).sign(signer);
+            } catch (Exception ioe) {
+                throw new RuntimeException(ioe);
+            }
+        };
+
+        testOfflineTokenMigration(convertOfflineTokenToKeycloak14Format);
+    }
+
+    private void testOfflineTokenMigration(OfflineTokenConverter offlineTokenConverter) throws Exception {
+        // Send request to obtain offline token
+        oauth.scope(OAuth2Constants.OFFLINE_ACCESS);
+        oauth.clientId("direct-grant");
+
+        OAuthClient.AccessTokenResponse tokenResponse = oauth.doGrantAccessTokenRequest("password", "test-user@localhost", "password");
+        Assert.assertNull(tokenResponse.getErrorDescription());
+        String offlineTokenString = tokenResponse.getRefreshToken();
+
+        // Convert offline token to the format of some old Keycloak version
+        FetchOnServerWrapper<String> fetch = new FetchOnServerWrapper<>() {
+
+            @Override
+            public FetchOnServer getRunOnServer() {
+                return session -> offlineTokenConverter.apply(session, offlineTokenString);
+            }
+
+            @Override
+            public Class<String> getResultClass() {
+                return String.class;
+            }
+
+        };
+        String modifiedOfflineToken = testingClient.server("test").fetch(fetch);
+        getLogger().infof("Modified offline token: %s", modifiedOfflineToken);
+
+        // Check it is possible to successfully refresh with the modified offline token
+        OAuthClient.AccessTokenResponse response = oauth.doRefreshTokenRequest(modifiedOfflineToken, "password");
+        AccessToken refreshedToken = oauth.verifyToken(response.getAccessToken());
+        Assert.assertEquals(200, response.getStatusCode());
+    }
+
+    public interface OfflineTokenConverter extends Serializable, BiFunction<KeycloakSession, String, String> {
+    }
+}