From 2596143e2bc42f5958e446ba6c156402ee1a8d53 Mon Sep 17 00:00:00 2001 From: Andre Heider Date: Wed, 15 Sep 2010 07:44:08 +0000 Subject: [PATCH] PLUGINS: Additional plugin check for the ELF loader. The ELF loader does not have access to the symbols of the main executable, it just relocates symbols to it via fixed offsets. We need to make sure that loaded plugins are from the same link process to prevent crashes. An embedded build date is used for that. svn-id: r52730 --- Makefile.common | 4 +++ backends/module.mk | 1 + backends/plugins/elf/elf-provider.cpp | 13 ++++++++++ backends/plugins/elf/elf-provider.h | 2 ++ backends/plugins/elf/plugin.syms | 1 + backends/plugins/elf/version.cpp | 32 ++++++++++++++++++++++++ backends/plugins/elf/version.h | 35 +++++++++++++++++++++++++++ base/plugins.h | 9 +++++++ configure | 2 +- 9 files changed, 98 insertions(+), 1 deletion(-) create mode 100644 backends/plugins/elf/version.cpp create mode 100644 backends/plugins/elf/version.h diff --git a/Makefile.common b/Makefile.common index 14d73405fdb..cf8626ce3c7 100644 --- a/Makefile.common +++ b/Makefile.common @@ -54,6 +54,10 @@ DEPFILES = # the build date in gScummVMBuildDate is correct. base/version.o: $(filter-out base/libbase.a,$(OBJS)) +ifdef USE_ELF_LOADER +backends/plugins/elf/version.o: $(filter-out base/libbase.a,$(filter-out backends/libbackends.a,$(OBJS))) +endif + # Replace regular output with quiet messages ifneq ($(findstring $(MAKEFLAGS),s),s) ifneq ($(VERBOSE_BUILD),1) diff --git a/backends/module.mk b/backends/module.mk index e0bdd26cf7d..b3a23f10e7f 100644 --- a/backends/module.mk +++ b/backends/module.mk @@ -28,6 +28,7 @@ MODULE_OBJS := \ plugins/elf/ppc-loader.o \ plugins/elf/arm-loader.o \ plugins/elf/elf-provider.o \ + plugins/elf/version.o \ plugins/dc/dc-provider.o \ plugins/posix/posix-provider.o \ plugins/sdl/sdl-provider.o \ diff --git a/backends/plugins/elf/elf-provider.cpp b/backends/plugins/elf/elf-provider.cpp index 8629de6c45f..d1c8f6aa051 100644 --- a/backends/plugins/elf/elf-provider.cpp +++ b/backends/plugins/elf/elf-provider.cpp @@ -112,6 +112,19 @@ bool ELFPlugin::loadPlugin() { return false; } + CharFunc buildDateFunc = (CharFunc)findSymbol("PLUGIN_getBuildDate"); + if (!buildDateFunc) { + unloadPlugin(); + warning("elfloader: plugin '%s' is missing symbols", _filename.c_str()); + return false; + } + + if (strncmp(gScummVMPluginBuildDate, buildDateFunc(), strlen(gScummVMPluginBuildDate))) { + unloadPlugin(); + warning("elfloader: plugin '%s' has a different build date", _filename.c_str()); + return false; + } + bool ret = DynamicPlugin::loadPlugin(); #ifdef ELF_LOADER_CXA_ATEXIT diff --git a/backends/plugins/elf/elf-provider.h b/backends/plugins/elf/elf-provider.h index 92fe5d63d12..0309ffcece6 100644 --- a/backends/plugins/elf/elf-provider.h +++ b/backends/plugins/elf/elf-provider.h @@ -45,6 +45,8 @@ */ class ELFPlugin : public DynamicPlugin { protected: + typedef const char *(*CharFunc)(); + DLObject *_dlHandle; Common::String _filename; void *_dso_handle; diff --git a/backends/plugins/elf/plugin.syms b/backends/plugins/elf/plugin.syms index 24ee1a19dc3..70465ae9762 100644 --- a/backends/plugins/elf/plugin.syms +++ b/backends/plugins/elf/plugin.syms @@ -1,3 +1,4 @@ +PLUGIN_getBuildDate PLUGIN_getVersion PLUGIN_getType PLUGIN_getTypeVersion diff --git a/backends/plugins/elf/version.cpp b/backends/plugins/elf/version.cpp new file mode 100644 index 00000000000..0277c6ae1cd --- /dev/null +++ b/backends/plugins/elf/version.cpp @@ -0,0 +1,32 @@ +/* ScummVM - Graphic Adventure Engine + * + * ScummVM is the legal property of its developers, whose names + * are too numerous to list here. Please refer to the COPYRIGHT + * file distributed with this source distribution. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + + * This program 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 for more details. + + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * $URL$ + * $Id$ + * + */ + +#include "backends/plugins/elf/version.h" + +#ifdef USE_ELF_LOADER +const char *gScummVMPluginBuildDate __attribute__((visibility("hidden"))) = + __DATE__ " " __TIME__ ; +#endif + diff --git a/backends/plugins/elf/version.h b/backends/plugins/elf/version.h new file mode 100644 index 00000000000..726204aeb74 --- /dev/null +++ b/backends/plugins/elf/version.h @@ -0,0 +1,35 @@ +/* ScummVM - Graphic Adventure Engine + * + * ScummVM is the legal property of its developers, whose names + * are too numerous to list here. Please refer to the COPYRIGHT + * file distributed with this source distribution. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program 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 for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * $URL$ + * $Id$ + */ + +#ifndef BACKENDS_PLUGINS_ELF_VERSION_H +#define BACKENDS_PLUGINS_ELF_VERSION_H + +#include "common/scummsys.h" + +#ifdef USE_ELF_LOADER +extern const char *gScummVMPluginBuildDate; +#endif + +#endif + diff --git a/base/plugins.h b/base/plugins.h index 0893312102e..5472ab2fce4 100644 --- a/base/plugins.h +++ b/base/plugins.h @@ -30,6 +30,7 @@ #include "common/error.h" #include "common/singleton.h" #include "common/util.h" +#include "backends/plugins/elf/version.h" namespace Common { class FSList; @@ -98,6 +99,13 @@ extern int pluginTypeVersions[PLUGIN_TYPE_MAX]; #define PLUGIN_DYNAMIC_DSO_HANDLE #endif +#ifdef USE_ELF_LOADER +#define PLUGIN_DYNAMIC_BUILD_DATE \ + PLUGIN_EXPORT const char *PLUGIN_getBuildDate() { return gScummVMPluginBuildDate; } +#else +#define PLUGIN_DYNAMIC_BUILD_DATE +#endif + /** * REGISTER_PLUGIN_STATIC is a convenience macro which is used to declare * the plugin interface for static plugins. Code (such as game engines) @@ -128,6 +136,7 @@ extern int pluginTypeVersions[PLUGIN_TYPE_MAX]; #define REGISTER_PLUGIN_DYNAMIC(ID,TYPE,PLUGINCLASS) \ extern "C" { \ PLUGIN_DYNAMIC_DSO_HANDLE \ + PLUGIN_DYNAMIC_BUILD_DATE \ PLUGIN_EXPORT int32 PLUGIN_getVersion() { return PLUGIN_VERSION; } \ PLUGIN_EXPORT int32 PLUGIN_getType() { return TYPE; } \ PLUGIN_EXPORT int32 PLUGIN_getTypeVersion() { return TYPE##_VERSION; } \ diff --git a/configure b/configure index a12a37540ff..95104491b4b 100755 --- a/configure +++ b/configure @@ -2112,7 +2112,7 @@ DYNAMIC_MODULES := 1 PLUGIN_PREFIX := PLUGIN_SUFFIX := .plg PLUGIN_EXTRA_DEPS = $(EXECUTABLE) -PLUGIN_LDFLAGS = -nostartfiles -Wl,-q,--just-symbols,$(EXECUTABLE),--retain-symbols-file,$(srcdir)/backends/plugins/elf/plugin.syms +PLUGIN_LDFLAGS = -nostartfiles backends/plugins/elf/version.o -Wl,-q,--just-symbols,$(EXECUTABLE),--retain-symbols-file,$(srcdir)/backends/plugins/elf/plugin.syms PRE_OBJS_FLAGS := -Wl,--whole-archive POST_OBJS_FLAGS := -Wl,--no-whole-archive '"$_mak_plugins"