idn wrapper - Client Side IDN Conversion Software for Windows Copyright (c) 2000,2001,2002 Japan Network Information Center. All rights reserved. *** NOTICE ****************************************************** If you have installed mDN Wrapper (former version of idn wrapper) on your system, you should unwrap all the programs before installing idn wrapper. ***************************************************************** 1. Introduction For supporting internationalized domain names, each client application should convert domain names (their encodings) to that DNS server accepts. This requires applications to handle internationalized domain names in its core, and it is the vendor's responsibility to make their programs IDN-compatible. Although there are ongoing efforts in IETF to standardize IDN framework (architecture, encoding etc.) and several RFCs are expected to be published soon as the result, not many applications support IDN to this date. So, there are needs for some helper application which makes legacy applications IDN-aware. `runidn' in idnkit is one of such solutions for Unix-like operating systems, and this software, `idn wrapper' is the one for Windows. On windows, name resolving request is passed to WINSOCK DLL. idn wrapper replaces WINSOCK DLL with the one that can handle IDN, which makes legacy windows applications compatible with IDN. 2. Architecture 2.1. Wrapper DLL Wrapper DLL resides between application and original DLL. It intercept application's calls to original DLL, and preforms some additional processing on those calls. +------------+ Call +------------+ Call +------------+ | |------->| |------->| | |Application | |Wrapper DLL | |Original DLL| | |<-------| |<-------| | +------------+ Return +------------+ Return +------------+ additional processing here DLL call from apllication is passed to wrapper DLL. Wrapper DLL then performs some additional processing on that call, and then calls original DLL. Also, result from original DLL will once passed to wrapper DLL and wrapper does additional process on that result, and finally result will passed to the application. idn wrapper provides wrapper DLLs for WINSOCK, WSOCK32.DLL WINSOCK V1.1 WS2_32.DLL WINSOCK V2.0 to resolve multi-lingual domain names. 2.2. Wrapping APIs idn wrapper performs additional processing on name resolving APIs in WINSOCK, listed below. both WINSOCK 1.1, WINSOCK 2.0 gethostbyaddr gethostbyname WSAAsyncGetHostByAddr WSAAsyncGetHostByName only in WINSOCK 2.0 getaddrinfo freeaddrinfo getnameinfo WSALookupServiceBeginA WSALookupServiceNextA WSALookupServiceEnd Some applications do not use these APIs to resolve domain names. `nslookup' is one of those programs. `nslookup' builds and parse DNS messages internally and does not use WINSOCK's name resolver APIs. idn wrapper cannot make those programs IDN-aware. NOTE: WINSOCK 2.0 also contains WIDE-CHARACTER based name resolution APIs, WSALookupServiceBeginW WSALookupServiceNextW idn wrapper does not wrap these APIs. These APIs are used in Microsoft's own internationalization framework. It is dangerous to convert to another internationalization framework. 2.3. Other APIs in WINSOCK For other APIs in WINSOCK, idn wrapper does nothing, only calls original DLL's entries. idn wrapper copies original WINSOCK DLLs with renaming as below, and forward requests to them. wsock32.dll -> wsock32o.dll ws2_32.dll -> ws2_32o.dll Wrappper DLL will be installed with original DLL names. So after installation of idn wrapper, WINSOCK DLLs should be wsock32.dll idn wrapper for WINSOCK V1.1 ws2_32.dll idn wrapper for WINSOCK V2.0 wsock32o.dll Original WINSOCK V1.1 DLL ws2_32o.dll Original WINSOCK V2.0 DLL 2.4. Asynchronous API Domain name conversion take place on request to DNS convert from local encoding to DNS compatible encoding response from DNS convert from DNS encoding to local encoding For synchronous APIs, local to DNS conversion is done before calling original API, and after return from original API, name should be converted from DNS encoding to local encoding. But WINSOCK having some asynchronous APIs, such as WSAAsyncGetHostByAddr WSAAsyncGetHostByName In these APIs, completion is notified with windows message. To perform DNS to local conversion, wrapper should hook target window procedure to capture those completion messages. So, if asynchronous API was called, idn wrapper set hook to target window procedure (passed with API parameter). If hook found notify message (also given with API parameter), then convert resulting name (in DNS encoding) to local encoding. 2.5. Installing Wrapper DLLs WINSOCK DLLs are placed at Windows's system directory. To wrap WINSOCK DLLs, one could do following sequence at system directory. + Rename Original WINSOCK DLLs ren wsock32.dll wsock32o.dll ren ws2_32.dll ws2_32o.dll + Install (copy in) Wrapper DLLs copy somewhere\wsock32.dll wsock32.dll copy somewhere\ws2_32.dll ws2_32.dll copy another DLLs also However, replacing DLLs in Window's system directory is very dangerous: a) If you re-install idn wrapper again, original WINSOCK DLLs may be lost. b) Some application or service pack will replace WINSOCK DLLs. It may corrupt WINSOCK environment. If these happen, at least networking does not work, and worse, Windows never startup again. So, idn wrapper usually does not wrap in the system directory, but wrap in each indivisual application's directory. In Windows, DLL will be searched in the following places: Application's Load Directory %SystemRoot%\System32 %SystemRoot% Directories in PATH and loaded & linked first found one. So if installed wrapper DLLs is found on application's load directory, the application's call to WINSOCK will wrapped. But some applications or DLLs are binded to specific DLL, they do not rely on above DLL's search path. For those applcaitons or DLLs, idn wrapper (in standard installation) cannot wrap them. NOTE: Netscape is one of those program. It cannot be wrapped if installed to applications directory. Also WINSOCK DLLs are also binded to related DLLs in system directory. On the other hand, Internet Explore or Window Media Player relys on standard DLL search path, and well wrapped with idn wrapper. 2.6. At which point conversion applied If windows supporting WINSOCK 2.0, there are DLLs one for 1.1 and another for 2.0, and call to WINSOCK 1.1 will redirected to 2.0 DLL. +------------+ Call +------------+ Call +------------+ | |------->| |------->| | |Application | |WINSOCK 1.1 | |WINSOCK 2.0 | | |<-------| |<-------| | +------------+ Return +------------+ Return +------------+ In this case, calls to 1.1 and 2.0 are both passed to 2.0 DLL. So conversion will done in WINSOCK 2.0 DLL side. If windows only supports WINSOCK 1.1, there's 1.1 DLL only. +------------+ Call +------------+ | |------->| | |Application | |WINSOCK 1.1 | | |<-------| | +------------+ Return +------------+ In this case, conversion must done in 1.1 DLL. If idn wrapper was installed on system directory, DLLs will work as described above. But if wrapper was installed on application's directory, call/return sequence changes. Original WINSOCK 1.1 DLL in windows seems binded to specific WINSOCK 2.0 DLL, placed at window's system diretory. So call from WINSOCK 1.1 to WINSOCK 2.0 will passed to original DLL (in system directory) and never passed to wrapper DLL in application's directory. So in this case, both 1.1 and 2.0 DLLs should coonvert domain name encodings. These DLL binding is not documented. It may be change on OS versions or DLL versions. So, mDn wrapper determines place of conversion on registry value. With this registry value, idn wrappper absolb OS/DLL variations. Registry values for idn wrapper will placed under HKEY_LOCAL_MACHINE\SOFTWARE\JPNIC\IDN HKEY_CURRENT_USER\SOFTWARE\JPNIC\IDN Place of conversion is determined with registry value "Where", Registry Value "Where" REG_DWORD 0 both on WINSOCK 1.1 and WINSOCK 2.0 1 if WINSOCK 2.0 exist, only in WINSOCK 2.0 otherwise, convert on WINSOCK 1.1 2 only in WINSOCK 1.1 3 only in WINSOCK 2.0 If you install idn wrapper into application's directory, use "0". If you install idn wrapper into system directory, use "1". If there are no "Where" value, idn wrapper uses "0" as default, it is suited to installation into application's directory (default installation). 2.7. Converting From/To Wrapper DLL convert resolving domain name encoded with local code to DNS server's encoding. Also, wrapper DLL convert resulting name ( encoded with DNS's encoding) back to local encoding. There are several proposals for DNS encodings to handle multi-lingual domain names. Wrapper DLL should be configured to convert to one of those encodings. This DNS side encoding will specified with registry. When installing idn wrapper, this registry will set to some (yet undefined) DNS encoding. Registry values for idn wrapper will placed under HKEY_LOCAL_MACHINE\SOFTWARE\JPNIC\IDN HKEY_CURRENT_USER\SOFTWARE\JPNIC\IDN DNS encoding name will given with registry value (REG_SZ) of "Encoding", this name must be one of encoding names which 'libmdn' recognize. Registry Value "Encoding" REG_SZ Encoding name of DNS server accepts. Local encodings (Windows Apllication Encodings) is generally acquired from process's code page. 'iconv' library, used for idn wrapper, generally accepts MS's codepage names. Some windows apllication encode domain name with some specific multi- lingual encoding. For example, if you configured IE to use UTF-8, then domain names are encoded with UTF-8. UTF-8 is one of proposed DNS encoding, but DNS server may expect another encoding. For those cases, idn wrapper accept program specific encoding as local encoding. These program specific local encoding should be marked in registry. Program specific registry setting will placed under HKEY_LOCAL_MACHINE\SOFTWARE\JPNIC\IDN\PerProg HKEY_CURRENT_USER\SOFTWARE\JPNIC\IDN\PerProg using program name (executable file name) as key. For example, setting specific to Internet Explore, it executable name is "IEXPLORE", will plcaed at HKEY_LOCAL_MACHINE\SOFTWARE\JPNIC\IDN\PerProg\IEXPLORE Local encoding name will specified with registry value (REG_SZ) of "Encoding". This name must be one of encoding names which ' recognize.libmdn' Registry Value "Encoding" REG_SZ Encoding name of application program encodes, if it is not system's default encoding. 3. Setup and Configuration idn wrapper wraps WINSOCK DLL by placing wrapper (fake) DLLs in the application's directory. For the installation, idn wrapper comes with a setup program and a configuration program. NOTE: You can also install idn wrapper DLLs in the Windows system directory. But this installation is very dangerous and may cause severe problems in your system. You should try it at your own risk. 3.1. Setup Program To install idn wrapper, run "setup.exe". Setup program will do: Installing Files Copy idn wrapper files (DLL, Program EXE, etc) into diretory "\Program Files\JPNIC\idn wrapper" This directory may be changed on setup sequence. Setting registry entries Setup program will create keys and values under registry: "HKEY_LOCAL_MACHINES\Software\JPNIC\IDN" InstallDir REG_SZ "" Pathname of the idn wrapper's installation directory. The installer makes copies of the original WINSOCK DLLs in that directory, which is referenced by the idn wrapper's fake DLLs. ConfFile REG_SZ "\idn.conf" Name of the idnkit's configuration file, which defines various parameter regarding multilingual domain name handling. See the contents of the file for details. This value can be changed with the Configuration Program or the registry editor. LogFile REG_SZ "\idn_wrapper.log" Name of the idn wrapper's log file. This value can be changed with the Configuration Program or the registry editor. LogLevel DWORD -1 Logging level. Default is -1, which indicates no logging is made. This value can be changed with the Configuration Program or the registry editor. PerProg KEY Under this key, idn wrapper set program specific values. idn wrapper uses program's executable name as key, and put values under that key. PerProg\\Where REG_DWORD Encoding Position PerProg\>progname>\Encoding REG_SZ Local Encoding Name Configuration program set local encpoding name. "Where" value is usually not required in standard installation. If you installed idn wrapper in system directory, chanage "Where" values to fit your environment. Creating ICON Setup program will create program icon for idn wrapper's configuration program, and put it into "Start Menu". You can start configuration program with it. 3.2. Configuration Program Configuration program is a tool for wrap specific program, or unwrap programs. If you start "Configuration Program", you'll get window like this. +---+-------------------------------------------------+---+---+---+ | | idn wrapper - Configuration | _ | O | X | +---+-------------------------------------------------+---+---+---+ | idn wrapper Configuration Program version X.X | +-----------------------------------------------------------------+ | Wrapped Program +---------+ | | +---------------------------------------------+---+ | Wrap.. | | | | | A | +---------+ | | | +---+ +---------+ | | | | | | Unwrap..| | | | | | +---------+ | | | | | +---------+ | | | | | |UnwrapAll| | | | | | +---------+ | | | | | +---------+ | | | | | |RewrapAll| | | | | | +---------+ | | | | | +---------+ | | | | | | Log.. | | | | | | +---------+ | | | | | +---------+ | | | +---+ |Advanced.| | | | | V | +---------+ | | +---+-------------------------------------+---+---+ +---------+ | | | < | | > | | Exit | | | +---+-------------------------------------+---+ +---------+ | +-----------------------------------------------------------------+ Listbox contains list of current wrapped programs. Initially it is empty. To wrap a program, press button "wrap". You'll get following dialog. +---+-------------------------------------------------+---+---+---+ | | idn wrapper - Wrap Executable | _ | O | X | +---+-------------------------------------------------+---+---+---+ | +----------------------------------------+ +--------+ | | Program: | | |Browse..| | | +----------------------------------------+ +--------+ | | +----------+ | | Encoding: | | o Default o UTF-8 | | +----------+ | | [] Force local DLL reference | +-----------------------------------------------------------------+ | +--------+ +--------+ | | | Wrap | | Cancel | | | +--------+ +--------+ | +-----------------------------------------------------------------+ First, enter program (executable name with full path) or browse wrapping exectable from file browser. Then set local encoding of that program. Usually use "Default" as local encoding. If target program uses internationalized encoding, then specify "UFT-8". The "Force local DLL reference" button controls the DLL search order of the program to be wrapped (Windows95 does not have this capability, hence this button does not appear). If it is checked, DLLs in the local directory (the directory which the executable file is in) are always preferred, even if the executable specifies otherwise. If you have problem with wrapping, checking this button may solve the problem, but it is also possible that it causes other problem. Finally, put "wrap" button to wrap specified program with given encoding. Wrapped program will be listed in listbox of the first window. When you install a new version of idn wrapper, you have to re-wrap your programs in order to update DLLs used for wrapping. "Rewrap all" button is provided for this purpose. Just press the button, and all the currently wrapped programs will be re-wrapped. To unwrap a program, press button "unwrap". You'll get following confirmating dialog. +---+-------------------------------------------------+---+---+---+ | | idn wrapper - Unwrap Executable | _ | O | X | +---+-------------------------------------------------+---+---+---+ | +---------------------------------------------------+ | | Program: | | | | +---------------------------------------------------+ | +-----------------------------------------------------------------+ | +--------+ +--------+ | | | Unwrap | | Cancel | | | +--------+ +--------+ | +-----------------------------------------------------------------+ If you unwrap a program, the program will be vanished from listbox of the first window. Also "Unwrap all" button is provided to unwrap all the programs that are currently wrapped. To configure logging, press button "log". You'll get the following dialog. +---+-------------------------------------------------+---+---+---+ | | idn wrapper - Log Configuration | _ | O | X | +---+-------------------------------------------------+---+---+---+ | Log Level: o None o Fatal o Error o Warning o Info o Trace | | | | +------------------------------------+ +---------+ | | Log File:| | | Browse..| | | +------------------------------------+ +---------+ | | +------+ +--------+ | |Log Operation: | View | | Delete | | | +------+ +--------+ | +-----------------------------------------------------------------+ | +--------+ +--------+ | | | OK | | Cancel | | | +--------+ +--------+ | +-----------------------------------------------------------------+ Logging level can be selected from the followings. None no logging at all Fatal only records fatal errors Error also records non-fatal errors Warning also records warning mssages Info also records informational messages Trace also records trace information Note that these levels are for log output from IDN library (idnkit.dll). idn wrapper itself supports only off (None) and on (the rest). Pathname of the log file can also be specified with this dialog. You can view the current log file contents by pressing "View" button, or delete it by "Delete" button. Note that log level and log file configuration doesn't affect already running processes. Press "advanced" button to invoke the advanced configuration dialog. This dialog is for advanced users and enables customization for some basic parameters which normal users need not change, since appropriate defaults are provided. +---+-------------------------------------------------+---+---+---+ | | idn wrapper - Advanced Configuration | _ | O | X | +---+-------------------------------------------------+---+---+---+ | IDN Wrapping Mode | | o Wrap both WINSOCK 1.1 and WINSOCK 2.0 | | o Wrap only WINSOCK 1.1 | | o Wrap only WINSOCK 2.0 | | o Wrap only WINSOCK 2.0 if it exists. | | Otherwise wrap only WINSOCK 1.1 | +-----------------------------------------------------------------+ | IDN Configuration | | +--------------------------------+ +----------+ | | Config File: | | | Browse.. | | | +--------------------------------+ +----------+ | | +------+ | | | Edit | | | +------+ | +-----------------------------------------------------------------+ | +--------+ +--------+ | | | OK | | Cancel | | | +--------+ +--------+ | +-----------------------------------------------------------------+ With the dialog users can do the following configuration. Wrapping Mode Customize wrapping mode. Normally the default item should be appropriate. Changing it to other item may help when you have problems. IDN Configuration Set the configuration file for multilingual domain name handling. By pressing "Edit" button, you can edit then contents of the file. 4. Limitations 4.1. DLL Versions Wrapper DLL is tightly coupled with specific DLL version, because it must export all the entries including un-documented ones. If WINSOCK DLL version changed, idn wrapper may not work correctly. Current idn wrapper is tested on Win2000 (WINSOCK 1.1 + 2.0) WinME (WINSOCK 1.1 + 2.0) But there are no assuarance for future versions of Windows. 4.2. DNS, WINS, LMHOSTS There are three name resolving methods in windows, DNS, WINS and LMHOSTS. Using idn wrapper, domain name conversion will performed on all of thoses methods. It may cause some trouble if windows using WINS or LMHOSTS. We recommend use DNS oly if you want to use idn wrapper. 4.3. Converting Names other than Domain Name In WINSOCK 2.0, there are generic name resolution APIs are introduced. WSALookupServiceBeginA WSALookupServiceNextA WSALookupServiceEnd They are use mainly domain name conversion now, but not limited to resolving domain name. idn wrapper hooks this API and convert given name anyway. This causes some trouble if conversion name is not domain name. 4.4. Applications don't use these APIa Some applications don't use these APIs to resolving domain names. For example, 'nslookup' issue DNS request locally. For these applications, idn wrapper does not work. 4.5. Applications bound to specific WINSOCK DLL Some applications are bound to specific DLL, not relying on standard DLL search path. Netscape Communicator seems to be one of such programs. idn wrapper in standard installation cannot wrap such programs. If you want to wrap those programs, you may use installation into system directory. But this installation is very dangerous, for it is possible that your system cannot boot again. 5. Registry Setting - Summary 5.1. Priority of Setting Settings of idn wrapper is placed on registry Software\JPNIC\IDN under HKEY_LOCAL_MACHINE or HKEY_CURRENT_USER. idn wrapper first read HKEY_LOCAL_MACHINE, and if HKEY_CURRENT_USER exist, overwrite with this one. Usually set HKEY_LOCAL_MACHINE only. But if you need per user setting, then set HKEY_CURRENT_USER. Note that the configuration program reads/writes only HKEY_LOCAL_MACHINE. 5.2. Registry Key There's common settings and per program settings. _Common Settings Software\JPNIC\IDN\InstallDir Installation directory Software\JPNIC\IDN\Where Where to convert encoding 0: both WINSOCK 1.1 and WINSOCK 2.0 1: if WINSOCK 2.0 exist, convert at 2.0 DLL if WINSOCK 1.1 only, convert at 1.1 DLL 2: only in WINSOCK1.1 3: only in WINSOCK2.0 Software\JPNIC\IDN\ConfFile idnkit Configuration File Software\JPNIC\IDN\LogFile Log File Software\JPNIC\IDN\LogLevel Log Level _Per Program Settings Converting position and program's local encoding may be set per program bases. Software\JPNIC\IDN\PerProg\\Where Software\JPNIC\IDN\PerProg\\Encoding If not specified, the following values are assumed. Where 0 (both 1.1 DLL and 2.0 DLL) Encoding [process's code page]