XAUTH(1) X Version 11(Release 5) XAUTH(1)
NAME
xauth - X authority file utility
SYNOPSIS
xauth [-f authfile] [-vqib] [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
to extract authorization records from one machine and merge them in on
another (as is the case when using remote logins or to grant 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.
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
environment 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 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 and should only be used to
clean up stale locks.
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
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each pair gives the most significant 4 bits of the octet and the
second digit of the pairgives 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.
[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 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, superceding 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.
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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
hostname/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 other xauth merge -
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. If this variable is not set, xauth will use
.Xauthority in the user's home directory.
HOME to get the user's home directory 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 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.
COPYRIGHT
Copyright 1989, Massachusetts Institute of Technology.
See X(1) for a full statement of rights and permissions.
AUTHOR
Jim Fulton, MIT X Consortium
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