1. Plugins Writing a "plugin" dissector is not very different from writing a standard one. In fact all of the functions described in README.dissector can be used in the plugins exactly as they are used in standard dissectors. (Note, however, that not all OSes on which Wireshark runs can support plugins.) If you've chosen "foo" as the name of your plugin (typically, that would be a short name for your protocol, in all lower case), the following instructions tell you how to implement it as a plugin. All occurrences of "foo" below should be replaced by the name of your plugin. 2. The directory for the plugin, and its files The plugin should be placed in a new plugins/foo directory which should contain at least the following files: AUTHORS COPYING ChangeLog CMakeLists.txt Makefile.am Makefile.common Makefile.nmake moduleinfo.h moduleinfo.nmake plugin.rc.in And of course the source and header files for your dissector. Examples of these files can be found in plugins/gryphon. 2.1 AUTHORS, COPYING, and ChangeLog The AUTHORS, COPYING, and ChangeLog are the standard sort of GPL project files. 2.2 CMakeLists.txt For your plugins/foo/CMakeLists.txt file, see the corresponding file in plugins/gryphon. Replace all occurrences of "gryphon" in those files with "foo" and add your source files to the DISSECTOR_SRC variable. 2.3 Makefile.am For your plugins/foo/Makefile.am file, see the corresponding file in plugins/gryphon. Replace all occurrences of "gryphon" in those files with "foo". 2.4 Makefile.common Your plugins/foo/Makefile.common should only list the main source file(s), which exports register_*() and handoff_*(), for your dissector in the DISSECTOR_SRC variable. All other supporting source files should be listed in the DISSECTOR_SUPPORT_SRC variable. The header files for your dissector, if any, must be listed in the DISSECTOR_INCLUDES variable. The DISSECTOR_INCLUDES variable should not include moduleinfo.h. 2.5 Makefile.nmake For your plugins/foo/Makefile.nmake file, see the corresponding file in plugins/gryphon. No modifications are needed here. 2.6 moduleinfo.h Your plugins/foo/moduleinfo.h file is used to set the version information for the plugin. 2.7 moduleinfo.nmake Your plugins/foo/moduleinfo.nmake is used to set the version information for building the plugin. Its contents should match that in moduleinfo.h 2.8 plugin.rc.in Your plugins/foo/plugin.rc.in is the Windows resource template file used to add the plugin specific information as resources to the DLL. No modifications are needed here. 3. Changes to existing Wireshark files There are two ways to add your plugin dissector to the build, as a custom extension or as a permanent addition. The custom extension is easy to configure, but won't be used for inclusion in the distribution if that's your goal. Setting up the permanent addition is somewhat more involved. 3.1 Custom extension Go to the plugins directory and copy the three Custom.*.example files to Custom.*. Now you have three files ready for building a plugin with the name "foo". Replace the name if you so require. If you want to add the plugin to your own Windows installer add a text file named custom_plugins.txt to the packaging/nsis directory, with a "File" statement for NSIS: File "..\..\plugins\foo\foo.dll" Then open packaging/nsis/Custom.nmake and add the relative path to your DLL to CUSTOM_PLUGINS: CUSTOM_PLUGINS= \ ../../plugins/foo/foo.dll 3.2 Permanent addition In order to be able to permanently add a plugin take the following steps. You will need to change the following files: configure.ac CMakeLists.txt epan/Makefile.am Makefile.am packaging/nsis/Makefile.nmake packaging/nsis/wireshark.nsi plugins/Makefile.am plugins/Makefile.nmake You might also want to search your Wireshark development directory for occurrences of an existing plugin name, in case this document is out of date with the current directory structure. For example, grep -rl gryphon . could be used from a shell prompt. 3.2.1 Changes to plugins/Makefile.am The plugins directory contains a Makefile.am. You need to add to SUBDIRS (in alphabetical order) the name of your plugin: SUBDIRS = $(_CUSTOM_SUBDIRS_) \ ... ethercat \ foo \ gryphon \ irda \ 3.2.2 Changes to plugins/Makefile.nmake In plugins/Makefile.nmake you need to add to PLUGINS_LIST (in alphabetical order) the name of your plugin: PLUGIN_LIST = \ ... ethercat \ foo \ gryphon \ irda \ 3.2.3 Changes to the top level Makefile.am Add your plugin (in alphabetical order) to plugin_ldadd: if HAVE_PLUGINS plugin_ldadd = $(_CUSTOM_plugin_ldadd_) \ ... -dlopen plugins/ethercat/ethercat.la \ -dlopen plugins/foo/foo.la \ -dlopen plugins/gryphon/gryphon.la \ -dlopen plugins/irda/irda.la \ ... 3.2.4 Changes to the top level configure.ac You need to add your plugins Makefile (in alphbetical order) to the AC_OUTPUT rule in the configure.ac AC_OUTPUT( ... plugins/ethercat/Makefile plugins/foo/Makefile plugins/gryphon/Makefile plugins/irda/Makefile ... ,) 3.2.5 Changes to epan/Makefile.am Add the relative path of all your plugin source files (in alphbetical order) to plugin_src: plugin_src = \ ... ../plugins/ethercat/packet-ioraw.c \ ../plugins/ethercat/packet-nv.c \ ../plugins/foo/packet-foo.c \ ../plugins/gryphon/packet-gryphon.c \ ../plugins/irda/packet-ircomm.c \ ../plugins/irda/packet-irda.c \ ... 3.2.6 Changes to CMakeLists.txt Add your plugin (in alphabetical order) to the PLUGIN_SRC_DIRS: if(ENABLE_PLUGINS) ... set(PLUGIN_SRC_DIRS ... plugins/ethercat plugins/foo plugins/gryphon plugins/irda ... 3.2.7 Changes to the installers If you want to include your plugin in an installer you have to add lines in the NSIS installer Makefile.nmake and wireshark.nsi files. 3.2.7.1 Changes to packaging/nsis/Makefile.nmake Add the relative path of your plugin DLL (in alphbetical order) to PLUGINS: PLUGINS= \ ... ../../plugins/ethercat/ethercat.dll \ ../../plugins/foo/foo.dll \ ../../plugins/gryphon/gryphon.dll \ ../../plugins/irda/irda.dll \ 3.2.7.2 Changes to packaging/nsis/wireshark.nsi Add the relative path of your plugin DLL (in alphbetical order) to the list of "File" statements in the "Dissector Plugins" section: File "${STAGING_DIR}\plugins\${VERSION}\ethercat.dll" File "${STAGING_DIR}\plugins\${VERSION}\foo.dll" File "${STAGING_DIR}\plugins\${VERSION}\gryphon.dll" File "${STAGING_DIR}\plugins\${VERSION}\irda.dll" 3.2.7.3 Other installers The U3 and PortableApps installers build their manifests, including plugins, from wireshark.nsi via the packaging/ws-manifest.pl script. 4. Development and plugins on Unix Plugins make some aspects of development easier and some harder. The first thing is that you'll have to run autogen.sh and configure once more to setup your build environment. The good news is that if you are working on a single plugin then you will find recompiling the plugin MUCH faster than recompiling a dissector and then linking it back into Wireshark. Use "make -C plugins" to compile just your plugins. The bad news is that Wireshark will not use the plugins unless the plugins are installed in one of the places it expects them to find. One way of dealing with this problem is to set an environment variable when running Wireshark: WIRESHARK_RUN_FROM_BUILD_DIRECTORY=1. Another way to deal with this problem is to set up a working root for wireshark, say in $HOME/build/root and build wireshark to install there ./configure --prefix=${HOME}/build/root && make install then subsequent rebuilds/installs of your plugin can be accomplished by going to the plugins/foo directory and running make install 5. Update "old style" plugins 5.1 How to update an "old style" plugin (using plugin_register and plugin_reg_handoff functions). The plugin registration has changed with the extension of the build scripts. These now generate the additional code needed for plugin encapsulation in plugin.c. When using the new style build scripts, stips the parts outlined below: o Remove the following include statements: #include #include "moduleinfo.h" o Removed the definition: #ifndef ENABLE_STATIC WS_DLL_PUBLIC_DEF gchar version[] = VERSION; #endif o Move relevant code from the blocks and delete these functions: #ifndef ENABLE_STATIC plugin_reg_handoff() .... #endif #ifndef ENABLE_STATIC plugin_register() .... #endif This will leave a clean dissector source file without plugin specifics. 5.2 How to update an "old style" plugin (using plugin_init function) The plugin registering has changed between 0.10.9 and 0.10.10; everyone is encouraged to update their plugins as outlined below: o Remove following include statements from all plugin sources: #include "plugins/plugin_api.h" #include "plugins/plugin_api_defs.h" o Remove the init function. o Add a new Makefile.common file with the lists of source files and headers. o Change the Makefile.am and Makefile.nmake files to match those of the DOCSIS plugin. ---------------- Ed Warnicke Guy Harris Derived and expanded from the plugin section of README.developers which was originally written by James Coe Gilbert Ramirez Jeff Foster Olivier Abad Laurent Deniel Jaap Keuter