/*

 * Copyright (c) 2014, 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "classfile/classFileStream.hpp"

#include "classfile/classListParser.hpp"

#include "classfile/classLoader.hpp"

#include "classfile/classLoaderData.inline.hpp"

#include "classfile/classLoaderExt.hpp"

#include "classfile/compactHashtable.inline.hpp"

#include "classfile/dictionary.hpp"

#include "classfile/javaClasses.hpp"

#include "classfile/sharedClassUtil.hpp"

#include "classfile/symbolTable.hpp"

#include "classfile/systemDictionary.hpp"

#include "classfile/systemDictionaryShared.hpp"

#include "classfile/verificationType.hpp"

#include "classfile/vmSymbols.hpp"

#include "logging/log.hpp"

#include "memory/allocation.hpp"

#include "memory/filemap.hpp"

#include "memory/metadataFactory.hpp"

#include "memory/metaspaceClosure.hpp"

#include "memory/oopFactory.hpp"

#include "memory/resourceArea.hpp"

#include "oops/instanceKlass.hpp"

#include "oops/klass.inline.hpp"

#include "oops/objArrayOop.inline.hpp"

#include "oops/oop.inline.hpp"

#include "oops/typeArrayOop.inline.hpp"

#include "runtime/handles.inline.hpp"

#include "runtime/java.hpp"

#include "runtime/javaCalls.hpp"

#include "runtime/mutexLocker.hpp"

#include "utilities/hashtable.inline.hpp"

#include "utilities/stringUtils.hpp"

objArrayOop SystemDictionaryShared::_shared_protection_domains  =  NULL;

objArrayOop SystemDictionaryShared::_shared_jar_urls            =  NULL;

objArrayOop SystemDictionaryShared::_shared_jar_manifests       =  NULL;

static Mutex* SharedDictionary_lock = NULL;

void SystemDictionaryShared::initialize(TRAPS) {

  if (_java_system_loader != NULL) {

    SharedDictionary_lock = new Mutex(Mutex::leaf, "SharedDictionary_lock", true);

    // These classes need to be initialized before calling get_shared_jar_manifest(), etc.

    SystemDictionary::ByteArrayInputStream_klass()->initialize(CHECK);

    SystemDictionary::File_klass()->initialize(CHECK);

    SystemDictionary::Jar_Manifest_klass()->initialize(CHECK);

    SystemDictionary::CodeSource_klass()->initialize(CHECK);

  }

}

oop SystemDictionaryShared::shared_protection_domain(int index) {

  return _shared_protection_domains->obj_at(index);

}

oop SystemDictionaryShared::shared_jar_url(int index) {

  return _shared_jar_urls->obj_at(index);

}

oop SystemDictionaryShared::shared_jar_manifest(int index) {

  return _shared_jar_manifests->obj_at(index);

}

Handle SystemDictionaryShared::get_shared_jar_manifest(int shared_path_index, TRAPS) {

  Handle empty;

  Handle manifest ;

  if (shared_jar_manifest(shared_path_index) == NULL) {

    SharedClassPathEntryExt* ent = (SharedClassPathEntryExt*)FileMapInfo::shared_path(shared_path_index);

    long size = ent->manifest_size();

    if (size <= 0) {

      return empty; // No manifest - return NULL handle

    }

    // ByteArrayInputStream bais = new ByteArrayInputStream(buf);

    InstanceKlass* bais_klass = SystemDictionary::ByteArrayInputStream_klass();

    Handle bais = bais_klass->allocate_instance_handle(CHECK_(empty));

    {

      const char* src = ent->manifest();

      assert(src != NULL, "No Manifest data");

      typeArrayOop buf = oopFactory::new_byteArray(size, CHECK_(empty));

      typeArrayHandle bufhandle(THREAD, buf);

      char* dst = (char*)(buf->byte_at_addr(0));

      memcpy(dst, src, (size_t)size);

      JavaValue result(T_VOID);

      JavaCalls::call_special(&result, bais, bais_klass,

                              vmSymbols::object_initializer_name(),

                              vmSymbols::byte_array_void_signature(),

                              bufhandle, CHECK_(empty));

    }

    // manifest = new Manifest(bais)

    InstanceKlass* manifest_klass = SystemDictionary::Jar_Manifest_klass();

    manifest = manifest_klass->allocate_instance_handle(CHECK_(empty));

    {

      JavaValue result(T_VOID);

      JavaCalls::call_special(&result, manifest, manifest_klass,

                              vmSymbols::object_initializer_name(),

                              vmSymbols::input_stream_void_signature(),

                              bais, CHECK_(empty));

    }

    atomic_set_shared_jar_manifest(shared_path_index, manifest());

  }

  manifest = Handle(THREAD, shared_jar_manifest(shared_path_index));

  assert(manifest.not_null(), "sanity");

  return manifest;

}

Handle SystemDictionaryShared::get_shared_jar_url(int shared_path_index, TRAPS) {

  Handle url_h;

  if (shared_jar_url(shared_path_index) == NULL) {

    JavaValue result(T_OBJECT);

    const char* path = FileMapInfo::shared_path_name(shared_path_index);

    Handle path_string = java_lang_String::create_from_str(path, CHECK_(url_h));

    Klass* classLoaders_klass =

        SystemDictionary::jdk_internal_loader_ClassLoaders_klass();

        JavaCalls::call_static(&result, classLoaders_klass,

                               vmSymbols::toFileURL_name(),

                               vmSymbols::toFileURL_signature(),

                               path_string, CHECK_(url_h));

    atomic_set_shared_jar_url(shared_path_index, (oop)result.get_jobject());

  }

  url_h = Handle(THREAD, shared_jar_url(shared_path_index));

  assert(url_h.not_null(), "sanity");

  return url_h;

}

Handle SystemDictionaryShared::get_package_name(Symbol* class_name, TRAPS) {

  ResourceMark rm(THREAD);

  Handle pkgname_string;

  char* pkgname = (char*) ClassLoader::package_from_name((const char*) class_name->as_C_string());

  if (pkgname != NULL) { // Package prefix found

    StringUtils::replace_no_expand(pkgname, "/", ".");

    pkgname_string = java_lang_String::create_from_str(pkgname,

                                                       CHECK_(pkgname_string));

  }

  return pkgname_string;

}

// Define Package for shared app classes from JAR file and also checks for

// package sealing (all done in Java code)

// See http://docs.oracle.com/javase/tutorial/deployment/jar/sealman.html

void SystemDictionaryShared::define_shared_package(Symbol*  class_name,

                                                   Handle class_loader,

                                                   Handle manifest,

                                                   Handle url,

                                                   TRAPS) {

  assert(class_loader == _java_system_loader, "unexpected class loader");

  // get_package_name() returns a NULL handle if the class is in unnamed package

  Handle pkgname_string = get_package_name(class_name, CHECK);

  if (pkgname_string.not_null()) {

    Klass* app_classLoader_klass = SystemDictionary::jdk_internal_loader_ClassLoaders_AppClassLoader_klass();

    JavaValue result(T_OBJECT);

    JavaCallArguments args(3);

    args.set_receiver(class_loader);

    args.push_oop(pkgname_string);

    args.push_oop(manifest);

    args.push_oop(url);

    JavaCalls::call_virtual(&result, app_classLoader_klass,

                            vmSymbols::defineOrCheckPackage_name(),

                            vmSymbols::defineOrCheckPackage_signature(),

                            &args,

                            CHECK);

  }

}

// Define Package for shared app/platform classes from named module

void SystemDictionaryShared::define_shared_package(Symbol* class_name,

                                                   Handle class_loader,

                                                   ModuleEntry* mod_entry,

                                                   TRAPS) {

  assert(mod_entry != NULL, "module_entry should not be NULL");

  Handle module_handle(THREAD, mod_entry->module());

  Handle pkg_name = get_package_name(class_name, CHECK);

  assert(pkg_name.not_null(), "Package should not be null for class in named module");

  Klass* classLoader_klass;

  if (SystemDictionary::is_system_class_loader(class_loader())) {

    classLoader_klass = SystemDictionary::jdk_internal_loader_ClassLoaders_AppClassLoader_klass();

  } else {

    assert(SystemDictionary::is_platform_class_loader(class_loader()), "unexpected classloader");

    classLoader_klass = SystemDictionary::jdk_internal_loader_ClassLoaders_PlatformClassLoader_klass();

  }

  JavaValue result(T_OBJECT);

  JavaCallArguments args(2);

  args.set_receiver(class_loader);

  args.push_oop(pkg_name);

  args.push_oop(module_handle);

  JavaCalls::call_virtual(&result, classLoader_klass,

                          vmSymbols::definePackage_name(),

                          vmSymbols::definePackage_signature(),

                          &args,

                          CHECK);

}

// Get the ProtectionDomain associated with the CodeSource from the classloader.

Handle SystemDictionaryShared::get_protection_domain_from_classloader(Handle class_loader,

                                                                      Handle url, TRAPS) {

  // CodeSource cs = new CodeSource(url, null);

  InstanceKlass* cs_klass = SystemDictionary::CodeSource_klass();

  Handle cs = cs_klass->allocate_instance_handle(CHECK_NH);

  JavaValue void_result(T_VOID);

  JavaCalls::call_special(&void_result, cs, cs_klass,

                          vmSymbols::object_initializer_name(),

                          vmSymbols::url_code_signer_array_void_signature(),

                          url, Handle(), CHECK_NH);

  // protection_domain = SecureClassLoader.getProtectionDomain(cs);

  Klass* secureClassLoader_klass = SystemDictionary::SecureClassLoader_klass();

  JavaValue obj_result(T_OBJECT);

  JavaCalls::call_virtual(&obj_result, class_loader, secureClassLoader_klass,

                          vmSymbols::getProtectionDomain_name(),

                          vmSymbols::getProtectionDomain_signature(),

                          cs, CHECK_NH);

  return Handle(THREAD, (oop)obj_result.get_jobject());

}

// Returns the ProtectionDomain associated with the JAR file identified by the url.

Handle SystemDictionaryShared::get_shared_protection_domain(Handle class_loader,

                                                            int shared_path_index,

                                                            Handle url,

                                                            TRAPS) {

  Handle protection_domain;

  if (shared_protection_domain(shared_path_index) == NULL) {

    Handle pd = get_protection_domain_from_classloader(class_loader, url, THREAD);

    atomic_set_shared_protection_domain(shared_path_index, pd());

  }

  // Acquire from the cache because if another thread beats the current one to

  // set the shared protection_domain and the atomic_set fails, the current thread

  // needs to get the updated protection_domain from the cache.

  protection_domain = Handle(THREAD, shared_protection_domain(shared_path_index));

  assert(protection_domain.not_null(), "sanity");

  return protection_domain;

}

// Returns the ProtectionDomain associated with the moduleEntry.

Handle SystemDictionaryShared::get_shared_protection_domain(Handle class_loader,

                                                            ModuleEntry* mod, TRAPS) {

  ClassLoaderData *loader_data = mod->loader_data();

  Handle protection_domain;

  if (mod->shared_protection_domain() == NULL) {

    Symbol* location = mod->location();

    if (location != NULL) {

      Handle url_string = java_lang_String::create_from_symbol(

                                 location, CHECK_(protection_domain));

      JavaValue result(T_OBJECT);

      Klass* classLoaders_klass =

        SystemDictionary::jdk_internal_loader_ClassLoaders_klass();

        JavaCalls::call_static(&result, classLoaders_klass, vmSymbols::toFileURL_name(),

                               vmSymbols::toFileURL_signature(),

                               url_string, CHECK_(protection_domain));

      Handle url = Handle(THREAD, (oop)result.get_jobject());

      Handle pd = get_protection_domain_from_classloader(class_loader, url, THREAD);

      mod->set_shared_protection_domain(loader_data, pd);

    }

  }

  protection_domain = Handle(THREAD, mod->shared_protection_domain());

  assert(protection_domain.not_null(), "sanity");

  return protection_domain;

}

// Initializes the java.lang.Package and java.security.ProtectionDomain objects associated with

// the given InstanceKlass.

// Returns the ProtectionDomain for the InstanceKlass.

Handle SystemDictionaryShared::init_security_info(Handle class_loader, InstanceKlass* ik, TRAPS) {

  Handle pd;

  if (ik != NULL) {

    int index = ik->shared_classpath_index();

    assert(index >= 0, "Sanity");

    SharedClassPathEntryExt* ent =

            (SharedClassPathEntryExt*)FileMapInfo::shared_path(index);

    Symbol* class_name = ik->name();

    if (ent->is_modules_image()) {

      // For shared app/platform classes originated from the run-time image:

      //   The ProtectionDomains are cached in the corresponding ModuleEntries

      //   for fast access by the VM.

      ResourceMark rm;

      ClassLoaderData *loader_data =

                ClassLoaderData::class_loader_data(class_loader());

      PackageEntryTable* pkgEntryTable = loader_data->packages();

      TempNewSymbol pkg_name = InstanceKlass::package_from_name(class_name, CHECK_(pd));

      if (pkg_name != NULL) {

        PackageEntry* pkg_entry = pkgEntryTable->lookup_only(pkg_name);

        if (pkg_entry != NULL) {

          ModuleEntry* mod_entry = pkg_entry->module();

          pd = get_shared_protection_domain(class_loader, mod_entry, THREAD);

          define_shared_package(class_name, class_loader, mod_entry, CHECK_(pd));

        }

      }

    } else {

      // For shared app/platform classes originated from JAR files on the class path:

      //   Each of the 3 SystemDictionaryShared::_shared_xxx arrays has the same length

      //   as the shared classpath table in the shared archive (see

      //   FileMap::_shared_path_table in filemap.hpp for details).

      //

      //   If a shared InstanceKlass k is loaded from the class path, let

      //

      //     index = k->shared_classpath_index():

      //

      //   FileMap::_shared_path_table[index] identifies the JAR file that contains k.

      //

      //   k's protection domain is:

      //

      //     ProtectionDomain pd = _shared_protection_domains[index];

      //

      //   and k's Package is initialized using

      //

      //     manifest = _shared_jar_manifests[index];

      //     url = _shared_jar_urls[index];

      //     define_shared_package(class_name, class_loader, manifest, url, CHECK_(pd));

      //

      //   Note that if an element of these 3 _shared_xxx arrays is NULL, it will be initialized by

      //   the corresponding SystemDictionaryShared::get_shared_xxx() function.

      Handle manifest = get_shared_jar_manifest(index, CHECK_(pd));

      Handle url = get_shared_jar_url(index, CHECK_(pd));

      define_shared_package(class_name, class_loader, manifest, url, CHECK_(pd));

      pd = get_shared_protection_domain(class_loader, index, url, CHECK_(pd));

    }

  }

  return pd;

}

// Currently AppCDS only archives classes from the run-time image, the

// -Xbootclasspath/a path, the class path, and the module path.

//

// Check if a shared class can be loaded by the specific classloader. Following

// are the "visible" archived classes for different classloaders.

//

// NULL classloader:

//   - see SystemDictionary::is_shared_class_visible()

// Platform classloader:

//   - Module class from runtime image. ModuleEntry must be defined in the

//     classloader.

// App classloader:

//   - Module Class from runtime image and module path. ModuleEntry must be defined in the

//     classloader.

//   - Class from -cp. The class must have no PackageEntry defined in any of the

//     boot/platform/app classloader, or must be in the unnamed module defined in the

//     AppClassLoader.

bool SystemDictionaryShared::is_shared_class_visible_for_classloader(

                                                     InstanceKlass* ik,

                                                     Handle class_loader,

                                                     const char* pkg_string,

                                                     Symbol* pkg_name,

                                                     PackageEntry* pkg_entry,

                                                     ModuleEntry* mod_entry,

                                                     TRAPS) {

  assert(class_loader.not_null(), "Class loader should not be NULL");

  assert(Universe::is_module_initialized(), "Module system is not initialized");

  ResourceMark rm(THREAD);

  int path_index = ik->shared_classpath_index();

  SharedClassPathEntry* ent =

            (SharedClassPathEntry*)FileMapInfo::shared_path(path_index);

  if (SystemDictionary::is_platform_class_loader(class_loader())) {

    assert(ent != NULL, "shared class for PlatformClassLoader should have valid SharedClassPathEntry");

    // The PlatformClassLoader can only load archived class originated from the

    // run-time image. The class' PackageEntry/ModuleEntry must be

    // defined by the PlatformClassLoader.

    if (mod_entry != NULL) {

      // PackageEntry/ModuleEntry is found in the classloader. Check if the

      // ModuleEntry's location agrees with the archived class' origination.

      if (ent->is_modules_image() && mod_entry->location()->starts_with("jrt:")) {

        return true; // Module class from the runtime image

      }

    }

  } else if (SystemDictionary::is_system_class_loader(class_loader())) {

    assert(ent != NULL, "shared class for system loader should have valid SharedClassPathEntry");

    if (pkg_string == NULL) {

      // The archived class is in the unnamed package. Currently, the boot image

      // does not contain any class in the unnamed package.

      assert(!ent->is_modules_image(), "Class in the unnamed package must be from the classpath");

      if (path_index >= ClassLoaderExt::app_class_paths_start_index()) {

        assert(path_index < ClassLoaderExt::app_module_paths_start_index(), "invalid path_index");

        return true;

      }

    } else {

      // Check if this is from a PackageEntry/ModuleEntry defined in the AppClassloader.

      if (pkg_entry == NULL) {

        // It's not guaranteed that the class is from the classpath if the

        // PackageEntry cannot be found from the AppClassloader. Need to check

        // the boot and platform classloader as well.

        if (get_package_entry(pkg_name, ClassLoaderData::class_loader_data_or_null(SystemDictionary::java_platform_loader())) == NULL &&

            get_package_entry(pkg_name, ClassLoaderData::the_null_class_loader_data()) == NULL) {

          // The PackageEntry is not defined in any of the boot/platform/app classloaders.

          // The archived class must from -cp path and not from the runtime image.

          if (!ent->is_modules_image() && path_index >= ClassLoaderExt::app_class_paths_start_index() &&

                                          path_index < ClassLoaderExt::app_module_paths_start_index()) {

            return true;

          }

        }

      } else if (mod_entry != NULL) {

        // The package/module is defined in the AppClassLoader. We support

        // archiving application module class from the runtime image or from

        // a named module from a module path.

        // Packages from the -cp path are in the unnamed_module.

        if (ent->is_modules_image() && mod_entry->location()->starts_with("jrt:")) {

          // shared module class from runtime image

          return true;

        } else if (pkg_entry->in_unnamed_module() && path_index >= ClassLoaderExt::app_class_paths_start_index() &&

            path_index < ClassLoaderExt::app_module_paths_start_index()) {

          // shared class from -cp

          DEBUG_ONLY( \

            ClassLoaderData* loader_data = class_loader_data(class_loader); \

            assert(mod_entry == loader_data->unnamed_module(), "the unnamed module is not defined in the classloader");)

          return true;

        } else {

          if(!pkg_entry->in_unnamed_module() &&

              (path_index >= ClassLoaderExt::app_module_paths_start_index())&&

              (path_index < FileMapInfo::get_number_of_shared_paths()) &&

              (strcmp(ent->name(), ClassLoader::skip_uri_protocol(mod_entry->location()->as_C_string())) == 0)) {

            // shared module class from module path

            return true;

          } else {

            assert(path_index < FileMapInfo::get_number_of_shared_paths(), "invalid path_index");

          }

        }

      }

    }

  } else {

    // TEMP: if a shared class can be found by a custom loader, consider it visible now.

    // FIXME: is this actually correct?

    return true;

  }

  return false;

}

// The following stack shows how this code is reached:

//

//   [0] SystemDictionaryShared::find_or_load_shared_class()

//   [1] JVM_FindLoadedClass

//   [2] java.lang.ClassLoader.findLoadedClass0()

//   [3] java.lang.ClassLoader.findLoadedClass()

//   [4] java.lang.ClassLoader.loadClass()

//   [5] jdk.internal.loader.ClassLoaders$AppClassLoader_klass.loadClass()

//

// Because AppCDS supports only the PlatformClassLoader and AppClassLoader, we make the following

// assumptions (based on the JDK 8.0 source code):

//

// [a] these two loaders use the default implementation of

//     ClassLoader.loadClass(String name, boolean resolve), which

// [b] calls findLoadedClass(name), immediately followed by parent.loadClass(),

//     immediately followed by findClass(name).

// [c] If the requested class is a shared class of the current class loader, parent.loadClass()

//     always returns null, and

// [d] if AppCDS is not enabled, the class would be loaded by findClass() by decoding it from a

//     JAR file and then parsed.

//

// Given these assumptions, we intercept the findLoadedClass() call to invoke

// SystemDictionaryShared::find_or_load_shared_class() to load the shared class from

// the archive. The reasons are:

//

// + Because AppCDS is a commercial feature, we want to hide the implementation. There

//   is currently no easy way to hide Java code, so we did it with native code.

// + Start-up is improved because we avoid decoding the JAR file, and avoid delegating

//   to the parent (since we know the parent will not find this class).

//

// NOTE: there's a lot of assumption about the Java code. If any of that change, this

// needs to be redesigned.

//

// An alternative is to modify the Java code of AppClassLoader.loadClass().

//

InstanceKlass* SystemDictionaryShared::find_or_load_shared_class(

                 Symbol* name, Handle class_loader, TRAPS) {

  if (DumpSharedSpaces) {

    return NULL;

  }

  InstanceKlass* k = NULL;

  if (shared_dictionary() != NULL &&

      UseAppCDS && (SystemDictionary::is_system_class_loader(class_loader()) ||

                    SystemDictionary::is_platform_class_loader(class_loader()))) {

    // Fix for 4474172; see evaluation for more details

    class_loader = Handle(

      THREAD, java_lang_ClassLoader::non_reflection_class_loader(class_loader()));