[#738] Fix dereferencing an alias that points into another backend (#741)

Valery Kharseko

yesterday c549b645f5300bed76e62614e0137c7eecc2e067

 opendj-server-legacy/src/test/java/org/openidentityplatform/opendj/AliasTestCase.java

@@ -11,7 +11,7 @@
 * Header, with the fields enclosed by brackets [] replaced by your own identifying
 * information: "Portions Copyright [year] [name of copyright owner]".
 *
 * Copyright 2024-2025 3A Systems, LLC.
 * Copyright 2024-2026 3A Systems, LLC.
 */
package org.openidentityplatform.opendj;

@@ -23,22 +23,29 @@
import org.opends.server.DirectoryServerTestCase;
import org.opends.server.TestCaseUtils;

import org.opends.server.backends.MemoryBackend;
import org.opends.server.types.Entry;
import org.testng.annotations.AfterClass;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.Test;

import java.util.HashMap;

import static org.assertj.core.api.Assertions.assertThat;
import static org.assertj.core.api.Assertions.fail;

@Test(sequential = true)
public class AliasTestCase extends DirectoryServerTestCase {
    /** Backend holding a naming context other than o=test, to check aliases crossing a backend boundary. */
    static final String OTHER_BACKEND_ID = "test2";

    Connection connection;

    @BeforeClass
    public void startServer() throws Exception {
        TestCaseUtils.startServer();
        TestCaseUtils.initializeTestBackend(true);
        TestCaseUtils.initializeMemoryBackend(OTHER_BACKEND_ID, "o=test2", true);

        TestCaseUtils.addEntries(
                 "dn: o=MyCompany, o=test",
@@ -116,6 +123,32 @@
                        "objectClass: extensibleObject",
                        "aliasedObjectName: uid=janedoe,ou=students,o=test",
                        "uid: janedoe",
                        "",

                        //an alias pointing into the o=test2 backend, and one pointing nowhere at all
                        "dn: ou=people,o=test2",
                        "objectClass: top",
                        "objectClass: organizationalUnit",
                        "ou: people",
                        "",
                        "dn: cn=Jane Roe,ou=people,o=test2",
                        "cn: Jane Roe",
                        "sn: Roe",
                        "objectclass: person",
                        "",
                        "dn: ou=external,o=test",
                        "objectClass: alias",
                        "objectClass: top",
                        "objectClass: extensibleObject",
                        "ou: external",
                        "aliasedObjectName: ou=people,o=test2",
                        "",
                        "dn: ou=nowhere,o=test",
                        "objectClass: alias",
                        "objectClass: top",
                        "objectClass: extensibleObject",
                        "ou: nowhere",
                        "aliasedObjectName: ou=people,o=missing",
                        ""
        );

@@ -125,6 +158,20 @@
        assertThat(connection.isValid()).isTrue();
    }

    @AfterClass
    public void stopServer() throws Exception {
        if (connection != null) {
            connection.close();
        }
        final MemoryBackend otherBackend = (MemoryBackend) TestCaseUtils.getServerContext()
                .getBackendConfigManager().getLocalBackendById(OTHER_BACKEND_ID);
        if (otherBackend != null) {
            otherBackend.clearMemoryBackend();
            otherBackend.finalizeBackend();
            TestCaseUtils.getServerContext().getBackendConfigManager().deregisterLocalBackend(otherBackend);
        }
    }

    public HashMap<String,SearchResultEntry> search(SearchScope scope,DereferenceAliasesPolicy policy) throws SearchResultReferenceIOException, LdapException {
        return search("ou=Area1,o=test", scope, policy);
    }
@@ -386,6 +433,37 @@
        assertThat(res.containsKey("uid=janedoe,ou=employees,o=test")).isFalse();
    }

    //    The alias target does not have to live in the backend holding the alias:
    //    the search must be handed over to the backend holding the target.
    @Test
    public void test_cross_backend_alias_base_always() throws LdapException, SearchResultReferenceIOException {
        HashMap<String, SearchResultEntry> res = search("ou=external,o=test", SearchScope.BASE_OBJECT, DereferenceAliasesPolicy.ALWAYS);

        assertThat(res.containsKey("ou=external,o=test")).isFalse();
        assertThat(res.containsKey("ou=people,o=test2")).isTrue();
        assertThat(res.containsKey("cn=Jane Roe,ou=people,o=test2")).isFalse();
    }

    @Test
    public void test_cross_backend_alias_sub_always() throws LdapException, SearchResultReferenceIOException {
        HashMap<String, SearchResultEntry> res = search("ou=external,o=test", SearchScope.WHOLE_SUBTREE, DereferenceAliasesPolicy.ALWAYS);

        assertThat(res.containsKey("ou=external,o=test")).isFalse();
        assertThat(res.containsKey("ou=people,o=test2")).isTrue();
        assertThat(res.containsKey("cn=Jane Roe,ou=people,o=test2")).isTrue();
    }

    //    No backend at all holds the alias target: this is a base DN that does not exist.
    @Test
    public void test_alias_target_without_backend() throws SearchResultReferenceIOException {
        try {
            search("ou=nowhere,o=test", SearchScope.BASE_OBJECT, DereferenceAliasesPolicy.ALWAYS);
            fail("dereferencing an alias whose target has no backend must fail");
        } catch (LdapException e) {
            assertThat(e.getResult().getResultCode()).isEqualTo(ResultCode.NO_SUCH_OBJECT);
        }
    }

    @Test(expectedExceptions = LdapException.class)
    public void test_stackoverflow() throws Exception {