[Entitlements] Instrument nio path

libs/entitlement/bridge/src/main/java/org/elasticsearch/entitlement/bridge/EntitlementChecker.java

@@ -58,6 +58,8 @@
 import java.nio.file.LinkOption;
 import java.nio.file.OpenOption;
 import java.nio.file.Path;
+import java.nio.file.WatchEvent;
+import java.nio.file.WatchService;
 import java.nio.file.attribute.FileAttribute;
 import java.nio.file.attribute.UserPrincipal;
 import java.nio.file.spi.FileSystemProvider;
@@ -652,4 +654,17 @@ void checkNewByteChannel(
     void checkName(Class<?> callerClass, FileStore that);
 
     void checkType(Class<?> callerClass, FileStore that);
+
+    // path
+    void checkPathToRealPath(Class<?> callerClass, Path that, LinkOption... options);
+
+    void checkPathRegister(Class<?> callerClass, Path that, WatchService watcher, WatchEvent.Kind<?>... events);
+
+    void checkPathRegister(
+        Class<?> callerClass,
+        Path that,
+        WatchService watcher,
+        WatchEvent.Kind<?>[] events,
+        WatchEvent.Modifier... modifiers
+    );
 }

libs/entitlement/qa/entitlement-test-plugin/src/main/java/org/elasticsearch/entitlement/qa/test/PathActions.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the "Elastic License
+ * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
+ * Public License v 1"; you may not use this file except in compliance with, at
+ * your election, the "Elastic License 2.0", the "GNU Affero General Public
+ * License v3.0 only", or the "Server Side Public License, v 1".
+ */
+
+package org.elasticsearch.entitlement.qa.test;
+
+import java.io.IOException;
+import java.nio.file.FileSystems;
+import java.nio.file.LinkOption;
+import java.nio.file.WatchEvent;
+
+import static org.elasticsearch.entitlement.qa.test.EntitlementTest.ExpectedAccess.PLUGINS;
+
+class PathActions {
+
+    @EntitlementTest(expectedAccess = PLUGINS)
+    static void checkToRealPath() throws IOException {
+        FileCheckActions.readFile().toRealPath();
+    }
+
+    @EntitlementTest(expectedAccess = PLUGINS)
+    static void checkToRealPathNoFollow() throws IOException {
+        FileCheckActions.readFile().toRealPath(LinkOption.NOFOLLOW_LINKS);
+    }
+
+    @SuppressWarnings("rawtypes")
+    @EntitlementTest(expectedAccess = PLUGINS)
+    static void checkRegister() throws IOException {
+        try (var watchService = FileSystems.getDefault().newWatchService()) {
+            FileCheckActions.readFile().register(watchService, new WatchEvent.Kind[0]);
+        } catch (IllegalArgumentException e) {
+            // intentionally no events registered
+        }
+    }
+
+    @SuppressWarnings("rawtypes")
+    @EntitlementTest(expectedAccess = PLUGINS)
+    static void checkRegisterWithModifiers() throws IOException {
+        try (var watchService = FileSystems.getDefault().newWatchService()) {
+            FileCheckActions.readFile().register(watchService, new WatchEvent.Kind[0], new WatchEvent.Modifier[0]);
+        } catch (IllegalArgumentException e) {
+            // intentionally no events registered
+        }
+    }
+}

libs/entitlement/qa/entitlement-test-plugin/src/main/java/org/elasticsearch/entitlement/qa/test/RestEntitlementsCheckAction.java

@@ -187,7 +187,7 @@ static CheckAction alwaysDenied(CheckedRunnable<Exception> action) {
         getTestEntries(SystemActions.class),
         getTestEntries(NativeActions.class),
         getTestEntries(NioFileSystemActions.class),
-        getTestEntries(FileStoreActions.class)
+        getTestEntries(PathActions.class)
     )
         .flatMap(Function.identity())
         .filter(entry -> entry.getValue().fromJavaVersion() == null || Runtime.version().feature() >= entry.getValue().fromJavaVersion())

libs/entitlement/src/main/java/org/elasticsearch/entitlement/initialization/EntitlementInitialization.java

@@ -44,6 +44,8 @@
 import java.nio.file.LinkOption;
 import java.nio.file.OpenOption;
 import java.nio.file.Path;
+import java.nio.file.WatchEvent;
+import java.nio.file.WatchService;
 import java.nio.file.attribute.FileAttribute;
 import java.nio.file.spi.FileSystemProvider;
 import java.util.ArrayList;
@@ -58,6 +60,7 @@
 import java.util.stream.Stream;
 import java.util.stream.StreamSupport;
 
+import static org.elasticsearch.entitlement.runtime.policy.entitlements.FilesEntitlement.Mode.READ;
 import static org.elasticsearch.entitlement.runtime.policy.entitlements.FilesEntitlement.Mode.READ_WRITE;
 
 /**
@@ -94,6 +97,7 @@ public static void initialize(Instrumentation inst) throws Exception {
         Stream.of(
             fileSystemProviderChecks(),
             fileStoreChecks(),
+            pathChecks(),
             Stream.of(
                 INSTRUMENTATION_SERVICE.lookupImplementationMethod(
                     SelectorProvider.class,
@@ -144,13 +148,30 @@ private static PolicyManager createPolicyManager() {
                         new OutboundNetworkEntitlement(),
                         new LoadNativeLibrariesEntitlement(),
                         new FilesEntitlement(
-                            List.of(new FilesEntitlement.FileData(EntitlementBootstrap.bootstrapArgs().tempDir().toString(), READ_WRITE))
+                            Stream.concat(
+                                Stream.of(
+                                    new FileData(EntitlementBootstrap.bootstrapArgs().tempDir().toString(), READ_WRITE),
+                                    new FileData(EntitlementBootstrap.bootstrapArgs().configDir().toString(), READ)
+                                ),
+                                Arrays.stream(dataDirs).map(d -> new FileData(d.toString(), READ))
+                            ).toList()
                         )
                     )
                 ),
                 new Scope("org.apache.httpcomponents.httpclient", List.of(new OutboundNetworkEntitlement())),
                 new Scope("io.netty.transport", List.of(new InboundNetworkEntitlement(), new OutboundNetworkEntitlement())),
-                new Scope("org.apache.lucene.core", List.of(new LoadNativeLibrariesEntitlement())),
+                new Scope(
+                    "org.apache.lucene.core",
+                    List.of(
+                        new LoadNativeLibrariesEntitlement(),
+                        new FilesEntitlement(
+                            Stream.concat(
+                                Stream.of(new FileData(EntitlementBootstrap.bootstrapArgs().configDir().toString(), READ)),
+                                Arrays.stream(dataDirs).map(d -> new FileData(d.toString(), READ_WRITE))
+                            ).toList()
+                        )
+                    )
+                ),
                 new Scope(
                     "org.elasticsearch.nativeaccess",
                     List.of(
@@ -255,6 +276,33 @@ public InstrumentationService.InstrumentationInfo of(String methodName, Class<?>
         });
     }
 
+    private static Stream<InstrumentationService.InstrumentationInfo> pathChecks() {
+        var pathClasses = StreamSupport.stream(FileSystems.getDefault().getRootDirectories().spliterator(), false)
+            .map(Path::getClass)
+            .distinct();
+        return pathClasses.flatMap(pathClass -> {
+            InstrumentationInfoFactory instrumentation = (String methodName, Class<?>... parameterTypes) -> INSTRUMENTATION_SERVICE
+                .lookupImplementationMethod(
+                    Path.class,
+                    methodName,
+                    pathClass,
+                    EntitlementChecker.class,
+                    "checkPath" + Character.toUpperCase(methodName.charAt(0)) + methodName.substring(1),
+                    parameterTypes
+                );
+
+            try {
+                return Stream.of(
+                    instrumentation.of("toRealPath", LinkOption[].class),
+                    instrumentation.of("register", WatchService.class, WatchEvent.Kind[].class),
+                    instrumentation.of("register", WatchService.class, WatchEvent.Kind[].class, WatchEvent.Modifier[].class)
+                );
+            } catch (NoSuchMethodException | ClassNotFoundException e) {
+                throw new RuntimeException(e);
+            }
+        });
+    }
+
     /**
      * Returns the "most recent" checker class compatible with the current runtime Java version.
      * For checkers, we have (optionally) version specific classes, each with a prefix (e.g. Java23).

libs/entitlement/src/main/java/org/elasticsearch/entitlement/runtime/api/ElasticsearchEntitlementChecker.java

@@ -14,6 +14,7 @@
 import org.elasticsearch.entitlement.runtime.policy.PolicyManager;
 
 import java.io.File;
+import java.io.IOException;
 import java.io.InputStream;
 import java.io.PrintStream;
 import java.io.PrintWriter;
@@ -64,6 +65,8 @@
 import java.nio.file.OpenOption;
 import java.nio.file.Path;
 import java.nio.file.StandardOpenOption;
+import java.nio.file.WatchEvent;
+import java.nio.file.WatchService;
 import java.nio.file.attribute.FileAttribute;
 import java.nio.file.attribute.UserPrincipal;
 import java.nio.file.spi.FileSystemProvider;
@@ -1322,4 +1325,40 @@ public void checkName(Class<?> callerClass, FileStore that) {
     public void checkType(Class<?> callerClass, FileStore that) {
         policyManager.checkReadStoreAttributes(callerClass);
     }
+
+    @Override
+    public void checkPathToRealPath(Class<?> callerClass, Path that, LinkOption... options) {
+        if (EntitlementChecker.class.isAssignableFrom(callerClass)) {
+            return;
+        }
+
+        boolean followLinks = true;
+        for (LinkOption option : options) {
+            if (option == LinkOption.NOFOLLOW_LINKS) {
+                followLinks = false;
+            }
+        }
+        if (followLinks) {
+            try {
+                policyManager.checkFileRead(callerClass, that.toRealPath());
+            } catch (IOException e) {}
+        }
+        policyManager.checkFileRead(callerClass, that);
+    }
+
+    @Override
+    public void checkPathRegister(Class<?> callerClass, Path that, WatchService watcher, WatchEvent.Kind<?>... events) {
+        policyManager.checkFileRead(callerClass, that);
+    }
+
+    @Override
+    public void checkPathRegister(
+        Class<?> callerClass,
+        Path that,
+        WatchService watcher,
+        WatchEvent.Kind<?>[] events,
+        WatchEvent.Modifier... modifiers
+    ) {
+        policyManager.checkFileRead(callerClass, that);
+    }
 }