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Date:      Fri, 21 May 2004 11:34:50 -0700
From:      Pete Carah <pete@altadena.net>
To:        current@freebsd.org
Subject:   ssh X forward broken
Message-ID:  <20040521183450.GA79447@users.altadena.net>

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Using a -current (a week or two old cvsup) ssh client against several
versions of server (some the same, some the version in 4.9) I'm getting
improper behavior of X forwarding; the emulated server has almost no
extensions and many calls fail.

ssh -v on client side:
port2# ssh -v
OpenSSH_3.8.1p1 FreeBSD-20040419, OpenSSL 0.9.7d 17 Mar 2004
...
sshd -v on server side:
OpenSSH_3.8.1p1 FreeBSD-20040419, OpenSSL 0.9.7d 17 Mar 2004
...

One example is that xclock reports the RENDER extension missing (but
then appears to work fine).  And scilab won't work at all remotely.

Is the ssh client side screening X calls now?

This is all with fairly current versions of X present (all 4.3.0)
on both sides.  xclock doesn't complain if it comes from a much older
X but that is probably because it doesn't try the extension.

xdpyinfo on X server (ssh client) side:
---------------------------------------
port2.altadena% xdpyinfo
name of display:    :0.0
version number:    11.0
vendor string:    The XFree86 Project, Inc
vendor release number:    40300000
XFree86 version: 4.3.0
maximum request size:  4194300 bytes
motion buffer size:  256
bitmap unit, bit order, padding:    32, LSBFirst, 32
image byte order:    LSBFirst
number of supported pixmap formats:    7
supported pixmap formats:
    depth 1, bits_per_pixel 1, scanline_pad 32
    depth 4, bits_per_pixel 8, scanline_pad 32
    depth 8, bits_per_pixel 8, scanline_pad 32
    depth 15, bits_per_pixel 16, scanline_pad 32
    depth 16, bits_per_pixel 16, scanline_pad 32
    depth 24, bits_per_pixel 32, scanline_pad 32
    depth 32, bits_per_pixel 32, scanline_pad 32
keycode range:    minimum 8, maximum 255
focus:  window 0x3e00005, revert to PointerRoot
number of extensions:    30
    BIG-REQUESTS
    DEC-XTRAP
    DOUBLE-BUFFER
    DPMS
    Extended-Visual-Information
    FontCache
    GLX
    LBX
    MIT-SCREEN-SAVER
    MIT-SHM
    MIT-SUNDRY-NONSTANDARD
    RANDR
    RECORD
    RENDER
    SECURITY
    SGI-GLX
    SHAPE
    SYNC
    TOG-CUP
    X-Resource
    XC-APPGROUP
    XC-MISC
    XFree86-Bigfont
    XFree86-DGA
    XFree86-Misc
    XFree86-VidModeExtension
    XInputExtension
    XKEYBOARD
    XTEST
    XVideo
default screen number:    0
number of screens:    1

screen #0:
  dimensions:    1024x768 pixels (347x260 millimeters)
  resolution:    75x75 dots per inch
  depths (7):    24, 1, 4, 8, 15, 16, 32
  root window id:    0x3b
  depth of root window:    24 planes
  number of colormaps:    minimum 1, maximum 1
  default colormap:    0x20
  default number of colormap cells:    256
  preallocated pixels:    black 0, white 16777215
  options:    backing-store NO, save-unders NO
  largest cursor:    64x64
  current input event mask:    0xda4031
    KeyPressMask             EnterWindowMask          LeaveWindowMask
    KeymapStateMask          StructureNotifyMask      SubstructureNotifyMask
    SubstructureRedirectMask PropertyChangeMask       ColormapChangeMask
  number of visuals:    4
  default visual id:  0x22
  visual:
    visual id:    0x22
    class:    TrueColor
    depth:    24 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0xff0000, 0xff00, 0xff
    significant bits in color specification:    8 bits
  visual:
    visual id:    0x23
    class:    TrueColor
    depth:    24 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0xff0000, 0xff00, 0xff
    significant bits in color specification:    8 bits
  visual:
    visual id:    0x24
    class:    TrueColor
    depth:    24 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0xff0000, 0xff00, 0xff
    significant bits in color specification:    8 bits
  visual:
    visual id:    0x25
    class:    TrueColor
    depth:    24 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0xff0000, 0xff00, 0xff
    significant bits in color specification:    8 bits

------------------------------------------------------------
xdpyinfo as seen when run on ssh server side:
---------------------------------------------
users.altadena% xdpyinfo
name of display:    localhost:12.0
version number:    11.0
vendor string:    The XFree86 Project, Inc
vendor release number:    40300000
XFree86 version: 4.3.0
maximum request size:  4194300 bytes
motion buffer size:  256
bitmap unit, bit order, padding:    32, LSBFirst, 32
image byte order:    LSBFirst
number of supported pixmap formats:    7
supported pixmap formats:
    depth 1, bits_per_pixel 1, scanline_pad 32
    depth 4, bits_per_pixel 8, scanline_pad 32
    depth 8, bits_per_pixel 8, scanline_pad 32
    depth 15, bits_per_pixel 16, scanline_pad 32
    depth 16, bits_per_pixel 16, scanline_pad 32
    depth 24, bits_per_pixel 32, scanline_pad 32
    depth 32, bits_per_pixel 32, scanline_pad 32
keycode range:    minimum 8, maximum 255
focus:  window 0x460000c, revert to PointerRoot
number of extensions:    3
    BIG-REQUESTS
    LBX
    XC-MISC
default screen number:    0
number of screens:    1

screen #0:
  dimensions:    1024x768 pixels (347x260 millimeters)
  resolution:    75x75 dots per inch
  depths (7):    24, 1, 4, 8, 15, 16, 32
  root window id:    0x3b
  depth of root window:    24 planes
  number of colormaps:    minimum 1, maximum 1
  default colormap:    0x20
  default number of colormap cells:    256
  preallocated pixels:    black 0, white 16777215
  options:    backing-store NO, save-unders NO
  largest cursor:    64x64
  current input event mask:    0xda4031
    KeyPressMask             EnterWindowMask          LeaveWindowMask
    KeymapStateMask          StructureNotifyMask      SubstructureNotifyMask
    SubstructureRedirectMask PropertyChangeMask       ColormapChangeMask
  number of visuals:    4
  default visual id:  0x22
  visual:
    visual id:    0x22
    class:    TrueColor
    depth:    24 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0xff0000, 0xff00, 0xff
    significant bits in color specification:    8 bits
  visual:
    visual id:    0x23
    class:    TrueColor
    depth:    24 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0xff0000, 0xff00, 0xff
    significant bits in color specification:    8 bits
  visual:
    visual id:    0x24
    class:    TrueColor
    depth:    24 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0xff0000, 0xff00, 0xff
    significant bits in color specification:    8 bits
  visual:
    visual id:    0x25
    class:    TrueColor
    depth:    24 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0xff0000, 0xff00, 0xff
    significant bits in color specification:    8 bits
--------------------------------------------------------

Another thing I see is that the xauth data on the emulated (sshd) side
appears to expire pretty fast - if I run most any program (like sending 
this mail) then try an X connection (:r !xdpyinfo in this edit session),
I get:
--------------------------
Xlib: connection to "localhost:10.0" refused by server
Xlib: Invalid MIT-MAGIC-COOKIE-1 key
xdpyinfo:  unable to open display "localhost:10.0".
------------------

The X server (ssh client) side of this is using both MIT and XDM
auth.  Other side is only MIT...

- Pete



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