The Linux Public Web Browser mini-HOWTO

The Linux Public Web Browser mini-HOWTO
Donald B. Marti Jr., [email protected]
v0.3, 5 January 1998

The basic idea here is to give web access to people who wander by,
while limiting their ability to mess anything up.

1. Copyright and Disclaimer

Copyright 1997 Donald B. Marti Jr. This document may be redistributed
under the terms of the Linux Documentation Project license.

This document currently contains information for Netscape Navigator
only, but I plan to add notes for other browsers too as I get the
necessary information. If you try this with a different browser,
please let me know.

2. Introduction

The basic idea here is to give web access to people who wander by,
while limiting their ability to mess anything up.

This setup was originally intended for trade shows, but it might be
applicable other places you want to have a web browser going without
having to babysit a computer.

Following these instructions does not make your system bulletproof or
idiot-proof.

3. Before you begin

3.1. You need a graphical browser

This document assumes that you already have a running graphical web
browser, such as Netscape Navigator, on your system. You should have
permission to use your graphical web browser. If you want to use
Netscape Navigator in a commercial setting, you can buy a copy with
appropriate license through Caldera.

3.2. You need to be able to add an account

If you don't have the right to be root, get the system administrator
to add the ``guest'' account and give you ownership of guest's home
directory. Skip to the ``Create or edit the following files'' step
(``Create or edit the following files in /home/guest'') when he or she
is done.

3.3. You need httpd for a stand-alone web browsing station

If you are setting up a web browsing station to run stand-alone,
without a network connection, you should have httpd working and the
web documents installed. To tell if this is the case, enter:

lynx -dump http://localhost/

You should get the text of the home page on your system.

4. Add the guest account

As root, run adduser to add a user named guest. Then enter

passwd guest

to set the password for the guest account. This should be something
easy to remember, like ``guest''. You will be telling people this
password. Don't make it the same as your own password.

Then make guest's home directory owned by you. Enter

chown me.mygroup /home/guest

Replace ``me'' with your regular username and ``mygroup'' with your
group name. (On Red Hat Linux, these will be the same, since every
user has his or her own group.)

You should now exit and do the rest of the steps as yourself, not
root.

5. Create or edit the following files in /home/guest

5.1. File name: .bash_login

______________________________________________________________________
exec startx
______________________________________________________________________

This means that when guest logs in, the login shell will start up the
X Window System right away.

5.2. File name: .Xclients

______________________________________________________________________
netscape
______________________________________________________________________

This means that when X starts, guest just gets the web browser, no
window manager. If you prefer another web browser, do something else.

The file .Xclients should be executable by guest. Enter

chmod 755 /home/guest/.Xclients

to make it so.

5.3. File name: .xsession

______________________________________________________________________
#!/bin/sh
netscape
______________________________________________________________________

If you use xdm(1) to log people in, this file should make guest get
the web browser as if he or she had logged in normally. The file
.xsession should be executable by guest. Enter

chmod 755 /home/guest/.xsession

to make it so.

5.4. File name: .Xdefaults

______________________________________________________________________
! Disable drag-to-select.
*hysteresis: 3000

! Make visited and unvisited links the same color by default
*linkForeground: #0000EE
*vlinkForeground: #0000EE

Netscape.Navigator.geometry: =NETSCAPE_GEOMETRY

! Disable some of the keyboard commands.
*globalTranslations:

! Mouse bindings: make all mouse buttons do the same thing.
*drawingArea.translations: #replace \
<Btn1Down>: ArmLink() \n\
<Btn2Down>: ArmLink() \n\
<Btn3Down>: ArmLink() \n\
~Shift<Btn1Up>: ActivateLink() \
DisarmLink() \n\
~Shift<Btn2Up>: ActivateLink() \
DisarmLink() \n\
~Shift<Btn3Up>: ActivateLink() \
DisarmLink() \n\
Shift<Btn1Up>: ActivateLink() \
DisarmLink() \n\
Shift<Btn2Up>: ActivateLink() \
DisarmLink() \n\
Shift<Btn3Up>: ActivateLink() \
DisarmLink() \n\
<Btn1Motion>: DisarmLinkIfMoved() \n\
<Btn2Motion>: DisarmLinkIfMoved() \n\
<Btn3Motion>: DisarmLinkIfMoved() \n\
<Motion>: DescribeLink() \n\
______________________________________________________________________

This file disables blink tags, drag-to-select, and some of the key
board commands. It also makes all mouse buttons do the same thing,
hides the menu bar, and makes visited and unvisited links the same
colour, so each visitor gets nice clean blue links, not ones that
other people have been thumbing through and staining purple.

You should replace the NETSCAPE_GEOMETRY in this file with an X
geometry that looks like this: XxY+0-0, where X is the width of your
screen and Y is the height of your screen + 32. This will position
the Netscape menu bar off the top of the screen, so the user won't be
distracted. For example, if your screen is 800x600, the geometry
should be 800x632+0-0.

6. Make a .netscape directory for guest

Enter

mkdir /home/guest/.netscape
chmod 777 /home/guest/.netscape

to create guest's .netscape directory and make it world-writable.

7. Try it

Log out, then log in as guest.

8. Changing preferences

Since you won't be able to use the menu bar as guest, you should edit
guest's preferences manually if you need to change them, or change
your own preferences to what you want guest's to be and copy the
preferences file.