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 infor-
       mation 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; xdm does that.

OPTIONS
       The  following options may be used with xauth.  They may be given indi-
       vidually (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
	       environment variable or .Xauthority in the user's  home	direc-
	       tory.

       -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 opera-
	       tions (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 (usu-
	       ally 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.

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 abbreviation 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 con-
	       nects to the server specified in displayname and uses the SECU-
	       RITY  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 authorization 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 authoriza-
	       tion will be considered untrusted and prevented	from  stealing
	       or  tampering  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	autho-
	       rization	 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
	       application 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 inter-
	       pretation 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 out-
	       put.  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  dis-
	       played  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, superceding any match-
	       ing 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 com-
	       mands 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.

       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 stan-
	       dard 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 informa-
       tion (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 | rsh 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.

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 use-
       ful 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 1.0.2			      XAUTH(1)