XAUTH(1)                                                      General Commands Manual                                                     XAUTH(1)

NAME

       xauth - X authority file utility

SYNOPSIS

       xauth [ -f authfile ] [ -vqibn ] [ command arg ... ]

DESCRIPTION

       The  xauth  program  is used to edit and display the authorization information used in connecting to the X server.  This program is usually
       used to extract authorization records from one machine and merge them in on another (as is the case when using remote  logins  or  granting
       access to other users).  Commands (described below) may be entered interactively, on the xauth command line, or in scripts.  Note that this
       program does not contact the X server except when the generate command is used.  Normally xauth is not used to create  the  authority  file
       entry in the first place; the program that starts the X server (often xdm or startx) does that.

OPTIONS

       The following options may be used with xauth.  They may be given individually (e.g., -q -i) or may combined (e.g., -qi).

       -f authfile
               This option specifies the name of the authority file to use.  By default, xauth will use the file specified by the XAUTHORITY envi-
               ronment variable or .Xauthority in the user's home directory.

       -q      This option indicates that xauth should operate quietly and not print unsolicited status messages.  This is the default if an xauth
               command is given on the command line or if the standard output is not directed to a terminal.

       -v      This  option  indicates  that xauth should operate verbosely and print status messages indicating the results of various operations
               (e.g., how many records have been read in or written out).  This is the default if xauth is  reading  commands  from  its  standard
               input and its standard output is directed to a terminal.

       -i      This option indicates that xauth should ignore any authority file locks.  Normally, xauth will refuse to read or edit any authority
               files that have been locked by other programs (usually xdm or another xauth).

       -b      This option indicates that xauth should attempt to break any authority file locks before proceeding.  Use this option only to clean
               up stale locks.

       -n      This  option  indicates  that xauth should not attempt to resolve any hostnames, but should simply always print the host address as
               stored in the authority file.

       -V      This option shows the version number of the xauth executable.

COMMANDS

       The following commands may be used to manipulate authority files:

       add displayname protocolname hexkey
               An authorization entry for the indicated display using the given protocol and key data is added to  the  authorization  file.   The
               data is specified as an even-lengthed string of hexadecimal digits, each pair representing one octet.  The first digit of each pair
               gives the most significant 4 bits of the octet, and the second digit of the pair gives the least significant 4 bits.  For  example,
               a  32 character hexkey would represent a 128-bit value.  A protocol name consisting of just a single period is treated as an abbre-
               viation for MIT-MAGIC-COOKIE-1.

       generate displayname protocolname [trusted|untrusted]
               [timeout seconds] [group group-id] [data hexdata]

               This command is similar to add.  The main difference is that instead of requiring the user to supply the key data, it  connects  to
               the  server  specified  in  displayname  and uses the SECURITY extension in order to get the key data to store in the authorization
               file.  If the server cannot be contacted or if it does not support the SECURITY extension, the command fails.  Otherwise, an autho-
               rization  entry  for the indicated display using the given protocol is added to the authorization file.  A protocol name consisting
               of just a single period is treated as an abbreviation for MIT-MAGIC-COOKIE-1.

               If the trusted option is used, clients that connect using this authorization will have full run  of  the  display,  as  usual.   If
               untrusted  is  used, clients that connect using this authorization will be considered untrusted and prevented from stealing or tam-
               pering with data belonging to trusted clients.  See the SECURITY extension specification  for  full  details  on  the  restrictions
               imposed on untrusted clients.  The default is untrusted.

               The timeout option specifies how long in seconds this authorization will be valid.  If the authorization remains unused (no clients
               are connected with it) for longer than this time period, the server purges the authorization, and future attempts to connect  using
               it  will  fail.  Note that the purging done by the server does not delete the authorization entry from the authorization file.  The
               default timeout is 60 seconds.

               The group option specifies the application group that clients connecting with this authorization should belong to.  See the  appli-
               cation group extension specification for more details.  The default is to not belong to an application group.

               The  data option specifies data that the server should use to generate the authorization.  Note that this is not the same data that
               gets written to the authorization file.  The interpretation of this data depends on the authorization protocol.  The hexdata is  in
               the same format as the hexkey described in the add command.  The default is to send no data.

       [n]extract filename displayname...
               Authorization  entries  for each of the specified displays are written to the indicated file.  If the nextract command is used, the
               entries are written in a numeric format suitable for non-binary transmission (such  as  secure  electronic  mail).   The  extracted
               entries  can be read back in using the merge and nmerge commands.  If the filename consists of just a single dash, the entries will
               be written to the standard output.

       [n]list [displayname...]
               Authorization entries for each of the specified displays (or all if no displays are named) are printed on the standard output.   If
               the nlist command is used, entries will be shown in the numeric format used by the nextract command; otherwise, they are shown in a
               textual format.  Key data is always displayed in the hexadecimal format given in the description of the add command.

       [n]merge [filename...]
               Authorization entries are read from the specified files and are merged into the authorization database,  superseding  any  matching
               existing  entries. If the nmerge command is used, the numeric format given in the description of the extract command is used.  If a
               filename consists of just a single dash, the standard input will be read if it hasn't been read before.

       remove displayname...
               Authorization entries matching the specified displays are removed from the authority file.

       source filename
               The specified file is treated as a script containing xauth commands to execute.  Blank lines and lines beginning with a sharp  sign
               (#) are ignored.  A single dash may be used to indicate the standard input, if it hasn't already been read.

       info    Information  describing  the authorization file, whether or not any changes have been made, and from where xauth commands are being
               read is printed on the standard output.

       exit    If any modifications have been made, the authority file is written out (if allowed), and the program exits.   An  end  of  file  is
               treated as an implicit exit command.

       quit    The program exits, ignoring any modifications.  This may also be accomplished by pressing the interrupt character.

       version This command shows the version number of the xauth executable.

       help [string]
               A  description  of all commands that begin with the given string (or all commands if no string is given) is printed on the standard
               output.

       ?       A short list of the valid commands is printed on the standard output.

DISPLAY NAMES

       Display names for the add, [n]extract, [n]list, [n]merge, and remove commands use the same format as the DISPLAY environment  variable  and
       the  common  -display  command line argument.  Display-specific information (such as the screen number) is unnecessary and will be ignored.
       Same-machine connections (such as local-host sockets, shared memory, and the Internet Protocol hostname localhost) are referred to as host-
       name/unix:displaynumber so that local entries for different machines may be stored in one authority file.

EXAMPLE

       The  most  common  use  for xauth is to extract the entry for the current display, copy it to another machine, and merge it into the user's
       authority file on the remote machine:

               %  xauth extract - $DISPLAY | ssh otherhost xauth merge -

       The following command contacts the server :0 to create an authorization using the MIT-MAGIC-COOKIE-1 protocol.  Clients that  connect  with
       this authorization will be untrusted.
            %  xauth generate :0 .

ENVIRONMENT

       This xauth program uses the following environment variables:

       XAUTHORITY
               to get the name of the authority file to use if the -f option isn't used.

       HOME    to get the user's home directory if XAUTHORITY isn't defined.

FILES

       $HOME/.Xauthority
               default authority file if XAUTHORITY isn't defined.

SEE ALSO

       X(7), Xsecurity(7), xhost(1), Xserver(1), xdm(1), startx(1), Xau(3).

BUGS

       Users  that  have  unsecure  networks  should  take  care  to  use encrypted file transfer mechanisms to copy authorization entries between
       machines.  Similarly, the MIT-MAGIC-COOKIE-1 protocol is not very useful in unsecure environments.  Sites that are interested in additional
       security may need to use encrypted authorization mechanisms such as Kerberos.

       Spaces are currently not allowed in the protocol name.  Quoting could be added for the truly perverse.

AUTHOR

       Jim Fulton, MIT X Consortium

X Version 11                                                       xauth 1.0.10                                                           XAUTH(1)