Provided by: dpkg-www_2.60_all 
NAME
dpkg-www, dpkg-www-installer - WWW Debian package browser
SYNOPSIS
https://<hostname>/cgi-bin/dpkg
DESCRIPTION
A typical Debian system can have hundreds installed packages and thousands available for installation.
Information about installed and available packages can usually be obtained with the dpkg(1) command, but
navigating through the package dependencies and the documentation files can be a very frustrating and
time-consuming task.
With the dpkg-www CGI you can instead browse Debian packages info with a web browser, following package
dependencies and locating documentation (man pages, Info files, READMEs, and so on) with few mouse
clicks. If you have superuser privileges you can even install, upgrade or remove packages from your web
browser. The output provided by dpkg-www is basically that of dpkg(1) with the addition of HREF's for
packages dependencies and documentation files.
The CGI program can take an optional query argument which can be given in the URL or entered in the query
field of the html form. This can be:
<empty>
list concisely all installed packages
* (asterisk)
list concisely all installed and available packages
<list of packages>
list concisely the requested packages
<wildcard expession>
list concisely all packages whose name matches the expression, for example '*image*' will find all
packages which contain the string 'image'.
<package>
list verbosely a package and, if the package is installed, all its files. If the package is not
installed and the web installation is enabled you can install it by clicking on the 'Install'
button. If the package is installed you can remove it or upgrade to a new version, if available,
by clicking on the respective buttons.
<absolute pathname>
list all the packages owners of a file. This can be used for example to find which package
installed a program.
/<regexp>
list all the packages owners of a file. The regexp form can be used to find which packages own a
non installed file.
<field>=<value>
list all the packages with control field matching value. If the field name is omitted the value is
searched in any control field. The default search is a case-insensitive fixed substring match but
it can be changed with the GREP_DCTRL_OPTS option in the config file. This feature works only if
the grep-dctrl(1) package is installed.
? (question mark)
show a concise help about the CGI usage.
<space> (a single space)
print only the input form, for use from window-manager menus.
Configuration
dpkg-www can be configured by the local system administrator via the optional /etc/dpkg-www.conf file.
This file is a simple Bourne shell (/bin/sh) script that defines some or all the following variables
(defaults are used if the file doesn't exist, or doesn't define the variable):
CHECK_BUTTONS
If this option is enabled dpkw-www will add a small 'install' check-button for each package shown
in the package list. Default is 0 (disabled) because the resulting interface is not very nice.
The use of this option is therefore not recommended.
INSTALL_BUTTON
If this option is set the 'Install' or 'Upgrade' and 'Remove' buttons will be added to the verbose
info of a package. By clicking on these button you will start the installation of removal the
package as described in the section Web Installation. Since this option can potentially introduce
security holes it is disabled (0) by default. Use at your own risk. If the variable is set to
"top" the button will be located before the file list, default is the bottom of the page.
SHOW_LOCAL_FILES
If this variable is set, dpkg-www will use file:/ style URL's to access html files -- bypassing
the CGI script. This is faster on slow machines. Default is not defined, which means use local
files for connection from localhost and https:// URL's for remote connections.
CHECK_PACKAGE_VERSION
If this variable is set, dpkg-www will check if a newer version of an installed package is
available. On slow machines you may want to set this option to false since it can considerably
slow down the execution.
LIST_UNAVAILABLE
This option enables listing also unavailable packages in the packages list. Disabled by default.
LIST_DOCUMENTATION
This option enables the display of references to documents registered with install-docs(8) to the
detailed package info, providing a quick path to relevant package documentation. Unfortunately
this feature is not totally reliable because currently there is no way to find documents
registered by a package with install-docs(8) and the search is done with an ugly hack. Hopefully
things will change in woody. This option is enabled (1) by default.
FORCE_SSH_PASSWD
This option forces ssh passwd prompt for package installation on a remote host even if an ssh
agent holds the private key.
GREP_DCTRL_OPTS
These options are passed to grep-dctrl(1) when doing a query by field. Default is "-i" for case-
insensitive fixed substring match. See grep-dctrl(1) for more info.
DPKG Command providing the dpkg(1) query functionalities. This can be dpkg(1) or dlocate(1), or auto.
Default is auto, meaning that the CGI will use dlocate(1) if installed, otherwise revert to
dpkg(1) which should always be available on a Debian system. By specifying this option you can
force the use of one of the two program.
MAN Manpage to HTML translation command. Can be dwww(7), man2html or auto . Default is auto, meaning
that the CGI will use man2thml if installed, otherwise revert to dwww(7). By specifying this
option you can force the use of one of the two program.
DEBIAN_CONTENTS
Optional list of one or more Contents-xxx.gz files mapping each file available in the Debian
system to the package from which it originates. If available these files are used to find the
owner packages of non installed files. This can be useful for quickly finding the package to
install when a needed command is missing.
BGCOLOR
background color of the HTML body.
DEBUG Internal option used only for debugging. Disabled by default since it is useless for normal users.
DWWW_PATH
Path on webserver to dwww(7) cgi-bin.
INFO2WWW_PATH
Path on webserver to info2www(1) cgi-bin.
The following is an exaple /etc/dpkg-www.conf file:
# Enable install check-buttons in package list.
CHECK_BUTTONS=0
# Enable install, upgrade and remove buttons in package info.
INSTALL_BUTTON=1
# List registered package documentation.
LIST_DOCUMENTATION=1
# Options passed to grep-dctrl in queryPackagesByField()
GREP_DCTRL_OPTS="-i"
# Show local files directly. Automatically set.
SHOW_LOCAL_FILES=auto
# Force ssh passwd prompt even if an ssh agent holds
# the private key.
FORCE_SSH_PASSWD=true
# List of Contents-xxx.gz files, if available.
DEBIAN_CONTENTS="
/debian/dists/buster/Contents-amd64.gz
/debian/dists/buster-updates/Contents-amd64.gz /debian-
security/dists/buster/updates/Contents-amd64.gz"
# Dpkg command (dpkg|dlocate|auto). Automatically detected.
# DPKG=auto
# Manpage conversion command (dwww|man2html|auto). Automatically detected.
# MAN=auto
# HTML background color.
# BGCOLOR="#c0c0c0"
# Enable CGI debugging. Not really useful.
# DEBUG=1
CGI access
The information provided by dpkg-www and the ability to install or remove packages also remotely can
potentially give useful information to crackers and open security holes. For these reasons access to this
CGI program should be allowed only from localhost and trusted hosts or domains. Unfortunately this
configuration is dependent on the particular installed web server. The dpkg-www package configures the
apache server, if installed, to allow access only from localhost. Other web servers must be configured
manually by the system administrator to restrict access to trusted hosts. If you administer many Debian
system on a local network you may want to enable access to the CGI from your network and browse packages
on any host from any other machine.
Web installation
If this option is enabled in the /etc/dpkg-www.conf file, the 'Install', 'Upgrade' and 'Remove' buttons
are added to the info page of installed or uninstalled packages. By clicking on this button the system
administrator, or more precisely any user who has the ability to become system administrator (since you
don't want to run a web browser as root!), will be able to install or remove a package on the fly,
provided he has properly configured his browser for web installation.
For security reasons the installation is done entirely from the browser side, so that you don't need to
gain root privileges from the CGI program which is run on the server. The only thing done on the server
is to generate an installation request which is downloaded to the browser for the execution, which is
started under control of the user and with his privileges. The real installation is done by a small
helper script run from the user's browser when a document with content-type
'application/dpkg-www-installer' is received from the web server. The helper script opens an XTerm on the
user's display and runs a script which becomes superuser, after asking the root password, and execs an
apt-get(8) command to install the requested packages.
The web browser must have been configured to handle the above content-type by running the command
"/usr/sbin/dpkg-www-installer -x -f '%s'", which must obviously be installed also on the client side if
installing remotely. If the dpkg-www package is not installed on the browser client you can simply copy
the script /usr/sbin/dpkg-www-installer and hope it works...
You can configure your Firefox browser from the General -> Application menu of the Preferences window.
You must add a new item with MIME type "application/dpkg-www-installer" and application
"/usr/sbin/dpkg-www-installer -x -f '%s'". This should add the following line to your Firefox mailcap
file:
application/dpkg-www-installer;/usr/sbin/dpkg-www-installer -x -f '%s'
The dpkg-www web installation has been successfully tested only with Firefox. With other web browsers it
is untested and it may not work correctly.
In order to be able to install the packages the user must known the root password asked for 'su root'
when installing on the local server, or have the ability to ssh as root to the remote host when
installing from a remote client.
From the security point of view, executing a web installation is functionally equivalent to opening a
shell in an XTerm, becoming superuser after having supplied the proper password and running apt-get(8) as
root to install or remove the required packages. Starting this from the web could be potentially
vulnerable to man-in-the-middle (MITM) attacks, but since it requires a password on the client it seems
quite safe. If you are really paranoid connect to a secure server from an SSL-enabled browser.
The dpkg-www web installation is not intended to replace the normal use of apt-get(8) from the shell. It
is provided only as a shortcut to allow the installation of a package after having located it with the
browser without needing to open a root shell and run apt-get(8) manually. For normal package maintenance
and system upgrade the use of apt-get(8) from the shell is recommended.
ENVIRONMENT
DPKG_WWW_HOST
The hostname to use.
FILES
/etc/dpkg-www.conf
Configuration file for dpkg-www. It is not necessary for this file to exist, there are sensible
defaults for everything.
SEE ALSO
dpkg(1), dwww(1), dwww(7), dlocate(1), man2html(8), grep-dctrl(1).
2019-02-26 DPKG-WWW(8)