ssh from Linux to cygwin/WXP: X forwarding "wrong authentication"

I would like to use my Win XP box as an SSHD server, so that I can log in from my Linux box and run X applications. But I'm having problems with X forwarding. I'm running the latest version of cygwin on Windows XP (see below for detailed version info).

The basic symptom:

• on the XP box ("xpgrave.localdomain"), under cygwin, I run "sshd -d"
• on the Linux box ("home.localdomain"), I run "ssh xpgrave -v -v -v"
• forwarding messages look OK, printenv DISPLAY returns "localhost:10.0"
• in the ssh session, I run "xterm"
• xterm craps out after printing (among other things, see below) the following error:

| X11 connection uses different authentication protocol.
| X11 connection rejected because of wrong authentication.

What have I done wrong? Things I made sure to check:

• xpgrave's /etc/sshd_config has "X11Forwarding yes"
• home's /etc/ssh/ssh_config contains "ForwardX11 yes"
• both machines can resolve each others' dns names forward and backward

Here's the output from xauth and printenv DISPLAY:

| [dave@xpgrave]~:{400}:$ xauth list
| XPGRAVE/unix:10 MIT-MAGIC-COOKIE-1 ef607cac5f573e2d76046e9ec7a95ee9
| [dave@xpgrave]~:{401}:$ printenv DISPLAY
| localhost:10.0
| [dave@xpgrave]~:{402}:$

Here is the actual output from the "sshd -d" process on the xpgrave:

| bash-2.05b$ /usr/sbin/sshd -d
| debug1: sshd version OpenSSH_3.4p1
| debug1: private host key: #0 type 0 RSA1

Do you need help?

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Here is the entire output from "ssh xpgrave -v -v -v" on the Linux box:

| OpenSSH_3.1p1, SSH protocols 1.5/2.0, OpenSSL 0x0090602f
| debug1: Reading configuration data /etc/ssh/ssh_config
| debug1: Applying options for *
| debug1: Rhosts Authentication disabled, originating port will not be trusted.
| debug1: restore_uid
| debug1: ssh_connect: getuid 500 geteuid 0 anon 1
| debug1: Connecting to xpgrave [192.168.0.250] port 22.
| debug1: temporarily_use_uid: 500/500 (e=0)
| debug1: restore_uid
| debug1: temporarily_use_uid: 500/500 (e=0)
| debug1: restore_uid
| debug1: Connection established.

Here is my entire cygwin version info (from inside the ssh session):

| [dave@xpgrave]~:{402}:$ cygcheck -s
|
| Cygwin Win95/NT Configuration Diagnostics
| Current System Time: Thu Nov 07 11:30:13 2002
|
| Windows XP Professional Ver 5.1 Build 2600
|
| Path: C:\cygwin\usr\local\bin
| C:\cygwin\bin
| C:\cygwin\bin
| C:\cygwin\sbin
| C:\cygwin\usr\sbin
| c:\WINDOWS\system32
| c:\WINDOWS
| c:\WINDOWS\System32\Wbem
| C:\cygwin\bin
| c:\Program Files\Microsoft Visual Studio\Common\Tools\WinNT
| c:\Program Files\Microsoft Visual Studio\Common\MSDev98\Bin
| c:\Program Files\Microsoft Visual Studio\Common\Tools
| c:\Program Files\Microsoft Visual Studio\VC98\bin
| C:\cygwin\usr\X11R6\bin
|
| SysDir: C:\WINDOWS\System32
| WinDir: C:\WINDOWS
|
| CYGWIN = `ntsec tty'
| HOME = `C:\cygwin\home\dave'
| MAKE_MODE = `unix'
| PWD = `/home/dave'
| USER = `dave'
|
| Use `-r' to scan registry
|
| a: fd N/A N/A
| c: hd NTFS 5985Mb 90% CP CS UN PA FC
| d: cd N/A N/A
|
| . /cygdrive user binmode,cygdrive
| C:/cygwin / system binmode
| C:/cygwin/bin /usr/bin system binmode
| C:/cygwin/lib /usr/lib system binmode
| C:\cygwin\usr\X11R6\lib\X11\fonts /usr/X11R6/lib/X11/fonts system binmode
| . /cygdrive user binmode,cygdrive
|
| Found: C:\cygwin\bin\bash.exe
| Found: C:\cygwin\bin\cat.exe
| Found: C:\cygwin\bin\cpp.exe
| Found: C:\cygwin\bin\find.exe
| Found: C:\cygwin\bin\gcc.exe
| Found: C:\cygwin\bin\gdb.exe
| Found: C:\cygwin\bin\ld.exe
| Found: C:\cygwin\bin\ls.exe
| Found: C:\cygwin\bin\make.exe
| Found: C:\cygwin\bin\sh.exe
|
| 58k 2002/05/07 C:\cygwin\bin\cygbz2-1.dll
| 625k 2002/08/09 C:\cygwin\bin\cygcrypto.dll
| 475k 2002/10/11 C:\cygwin\bin\cygcurl-2.dll
| 50k 2002/03/17 C:\cygwin\bin\cygexslt-0.dll
| 45k 2001/04/25 C:\cygwin\bin\cygform5.dll
| 35k 2002/01/09 C:\cygwin\bin\cygform6.dll
| 19k 2002/02/20 C:\cygwin\bin\cyggdbm.dll
| 17k 2001/06/28 C:\cygwin\bin\cyghistory4.dll
| 20k 2002/10/10 C:\cygwin\bin\cyghistory5.dll
| 929k 2002/06/24 C:\cygwin\bin\cygiconv-2.dll
| 22k 2001/12/13 C:\cygwin\bin\cygintl-1.dll
| 28k 2002/09/20 C:\cygwin\bin\cygintl-2.dll
| 21k 2001/06/20 C:\cygwin\bin\cygintl.dll
| 81k 2000/12/05 C:\cygwin\bin\cygitcl30.dll
| 35k 2000/12/05 C:\cygwin\bin\cygitk30.dll
| 45k 2002/02/08 C:\cygwin\bin\cygjbig1.dll
| 119k 2002/02/09 C:\cygwin\bin\cygjpeg6b.dll
| 59k 2002/09/20 C:\cygwin\bin\cygkpathsea-3-3-7.dll
| 25k 2002/07/16 C:\cygwin\bin\cygltdl-3.dll
| 26k 2001/04/25 C:\cygwin\bin\cygmenu5.dll
| 20k 2002/01/09 C:\cygwin\bin\cygmenu6.dll
| 156k 2001/04/25 C:\cygwin\bin\cygncurses++5.dll
| 175k 2002/01/09 C:\cygwin\bin\cygncurses++6.dll
| 226k 2001/04/25 C:\cygwin\bin\cygncurses5.dll
| 202k 2002/01/09 C:\cygwin\bin\cygncurses6.dll
| 15k 2001/04/25 C:\cygwin\bin\cygpanel5.dll
| 12k 2002/01/09 C:\cygwin\bin\cygpanel6.dll
| 40k 2001/11/21 C:\cygwin\bin\cygpcre.dll
| 39k 2001/11/21 C:\cygwin\bin\cygpcreposix.dll
| 175k 2002/07/22 C:\cygwin\bin\cygpng10.dll
| 179k 2002/07/22 C:\cygwin\bin\cygpng12.dll
| 170k 2002/01/21 C:\cygwin\bin\cygpng2.dll
| 22k 2002/06/09 C:\cygwin\bin\cygpopt-0.dll
| 108k 2001/06/28 C:\cygwin\bin\cygreadline4.dll
| 127k 2002/10/10 C:\cygwin\bin\cygreadline5.dll
| 66k 2001/11/20 C:\cygwin\bin\cygregex.dll
| 159k 2002/08/09 C:\cygwin\bin\cygssl.dll
| 390k 2000/12/05 C:\cygwin\bin\cygtcl80.dll
| 5k 2000/12/05 C:\cygwin\bin\cygtclpip80.dll
| 10k 2000/12/05 C:\cygwin\bin\cygtclreg80.dll
| 253k 2002/02/10 C:\cygwin\bin\cygtiff3.dll
| 623k 2000/12/05 C:\cygwin\bin\cygtk80.dll
| 633k 2002/07/22 C:\cygwin\bin\cygxml2-2.dll
| 41k 2002/01/20 C:\cygwin\bin\cygXpm-noX4.dll
| 46k 2002/01/20 C:\cygwin\bin\cygXpm-X4.dll
| 152k 2002/03/17 C:\cygwin\bin\cygxslt-1.dll
| 15k 2002/03/17 C:\cygwin\bin\cygxsltbreakpoint-1.dll
| 50k 2002/03/12 C:\cygwin\bin\cygz.dll
| 905k 2002/10/24 C:\cygwin\bin\cygwin1.dll
| Cygwin DLL version info:
| DLL version: 1.3.14
| DLL epoch: 19
| DLL bad signal mask: 19005
| DLL old termios: 5
| DLL malloc env: 28
| API major: 0
| API minor: 62
| Shared data: 3
| DLL identifier: cygwin1
| Mount registry: 2
| Cygnus registry name: Cygnus Solutions
| Cygwin registry name: Cygwin
| Program options name: Program Options
| Cygwin mount registry name: mounts v2
| Cygdrive flags: cygdrive flags
| Cygdrive prefix: cygdrive prefix
| Cygdrive default prefix:
| Build date: Thu Oct 24 10:48:11 EDT 2002
| Shared id: cygwin1S3
|
| 41k 2002/05/14 C:\cygwin\usr\X11R6\bin\cygPropList-0.dll
|
| Cygwin Package Information
| Package Version
| WindowMaker 0.80.0-2
| XFree86-base 4.2.0-1
| XFree86-bin 4.2.0-2
| XFree86-doc 4.2.0-1
| XFree86-etc 4.2.0-1
| XFree86-f100 4.2.0-2
| XFree86-fcyr 4.2.0-2
| XFree86-fenc 4.2.0-2
| XFree86-fnts 4.2.0-2
| XFree86-fscl 4.2.0-2
| XFree86-fsrv 4.2.0-1
| XFree86-lib 4.2.0-3
| XFree86-nest 4.2.0-1
| XFree86-prog 4.2.0-1
| XFree86-startup-scripts4.2.0-3
| XFree86-vfb 4.2.0-1
| XFree86-xserv 4.2.0-15
| Xaw3d 1.5-1
| _update-info-dir 00078-1
| ash 20020731-1
| autoconf 2.53b-1
| autoconf-devel 2.53a-1
| autoconf-stable 2.13-4
| automake 1.6.2-1
| automake-devel 1.6.2-1
| automake-stable 1.4p5-5
| base-files 1.0-1
| base-passwd 1.0-1
| bash 2.05b-5
| bc 1.06-1
| binutils 20020706-2
| bison 1.75-1
| byacc 1.9-1
| bzip2 1.0.2-2
| cgoban 1.9.12-1
| clear 1.0-1
| compface 1.4-5
| cpio 2.4.2
| cron 3.0.1-7
| crypt 1.0-1
| ctags 5.2-1
| curl 7.10.1-1
| cvs 1.11.0-1
| cygrunsrv 0.95-1
| cygutils 1.1.2-1
| cygwin 1.3.14-1
| cygwin-doc 1.2-1
| dejagnu 20010117-1
| diff 1.0-1
| diffutils 2.8.1-1
| ed 0.2-1
| emacs 21.2-8
| emacs-X11 21.2-8
| emacs-el 21.2-8
| expect 20010117-1
| figlet 2.2-1
| file 3.37-1
| fileutils 4.1-1
| findutils 4.1.7-4
| flex 2.5.4-2
| fortune 1.8-2
| fvwm 2.4.7-2
| gawk 3.1.1-5
| gcc 3.2-1
| gcc-mingw 3.2-20020817-1
| gdb 20010428-3
| gdbm 1.8.0-4
| gettext 0.11.5-1
| ghostscript 7.05-2
| ghostscript-base 7.05-2
| ghostscript-x11 7.05-2
| gnugo 3.2-1
| gperf 0.0
| grep 2.5-1
| groff 1.17.2-1
| gzip 1.3.3-4
| indent 2.2.8-1
| inetutils 1.3.2-19
| irc 20010101-1
| jbigkit 1.2-6
| jpeg 6b-7
| less 374-1
| lesstif 0.93.18-3
| libPropList 0.10.1-3
| libbz2_1 1.0.2-2
| libiconv2 1.8-2
| libintl 0.10.38-3
| libintl1 0.10.40-1
| libintl2 0.11.5-1
| libkpathsea3 20020911-1
| libltdl3 20020705-2
| libncurses5 5.2-1
| libncurses6 5.2-8
| libpng 1.2.4-2
| libpng10 1.0.14-2
| libpng10-devel 1.0.14-2
| libpng12 1.2.4-2
| libpng12-devel 1.2.4-2
| libpng2 1.0.12-1
| libpopt0 1.6.4-4
| libreadline4 4.1-2
| libreadline5 4.3-2
| libtool 20020705-1
| libtool-devel 20020705-2
| libtool-stable 1.4.2-2
| libxml2 2.4.23-1
| libxslt 1.0.13-1
| links 0.96-1
| login 1.4-4
| lynx 2.8.4-1
| m4 0.0
| make 3.79.1-7
| man 1.5g-2
| mingw-runtime 2.2-1
| mktemp 1.4-1
| mt 2.0.1-1
| mutt 1.4-1
| nano 1.1.10-1
| ncftp 3.1.4-1
| ncurses 5.2-8
| newlib-man 20020801
| openbox 0.99.1-3
| opengl 1.1.0-6
| openssh 3.4p1-5
| openssl 0.9.6g-1
| openssl-devel 0.9.6g-1
| patch 2.5-3
| pcre 3.7-1
| perl 5.6.1-2
| pkgconfig 0.12.0-1
| popt 1.6.4-4
| postgresql 7.2.3-1
| python 2.2.1-1
| rcs 5.7-3
| readline 4.3-2
| regex 4.4-2
| robots 2.0-1
| rsync 2.5.5-1
| rxvt 2.7.2-14
| sed 3.02-1
| sh-utils 2.0-2
| sharutils 4.2.1-2
| shutdown 1.2-2
| squid 2.4.STABLE7-1
| ssmtp 2.38.7-3
| tar 1.13.25-1
| tcltk 20001125-1
| tcsh 6.11.00-4
| termcap 20020930-1
| terminfo 5.2-3
| tetex 20020911-1
| tetex-base 20020911-1
| tetex-beta 20020911-1
| tetex-bin 20020911-1
| tetex-doc 20020911-1
| tetex-extra 20020911-1
| tetex-tiny 20020911-1
| texinfo 4.2-4
| texmf 20020911-1
| texmf-base 20020911-1
| texmf-doc 20020911-1
| texmf-extra 20020911-1
| texmf-tiny 20020911-1
| textutils 2.0.21-1
| tiff 3.5.7-1
| time 1.7-1
| ttcp 19980512-1
| units 1.77-1
| unzip 5.50-1
| vim 6.1-2
| w32api 2.0-1
| wget 1.8.2-1
| which 1.5-1
| whois 4.5.17-1
| x2x 1.27-2
| xpm-nox 4.2.0-1
| zip 2.3-2
| zlib 1.1.4-1
|
| Use -h to see help about each section
| [dave@xpgrave]~:{403}:$
Received on Sat Nov 9 01:02:43 2002