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
command, but navigating through the package dependencies and the
documentation files can be a very frustrating and time-consuming task.
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 a few mouse clicks. If you have
superuser privileges you can even install, upgrade or remove packages
from your WEB browser.
The output provided by
is basically that of
with the addition of HREF's for packages dependencies and documentation
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:
list concisely all installed packages
list concisely all installed and available packages
<list of packages>
list concisely the requested packages
list concisely all packages whose name matches the expression, for
example `*image*' will find all packages which contain the string `image'.
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.
list all the packages owners of a file. This can be used for example to find
which package installed a program.
list all the packages owners of a file. The regexp form can be used to find
which packages own a non installed file.
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
option in the config file.
This feature works only if the
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.
dpkg-www can be configured by the local system administrator via the optional
This file is a simple Bourne shell
script that defines some or all the following variables
(defaults are used if the file doesn't exist, or doesn't define the variable):
If this option is enabled
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.
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
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.
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 http:// URL's for remote connections.
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.
This option enables listing also unavailable packages in the packages list.
Disabled by default.
This option enables the display of references to documents registered with
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
and the search is done with an ugly hack. Hopefully things will change in
woody. This option is enabled (1) by default.
This option forces ssh passwd prompt for package installation on a remote host
even if an ssh agent holds the private key.
These options are passed to
when doing a query by field. Default is "-i" for case-insensitive fixed
substring match. See
for more info.
Command providing the
query functionalities. This can be
Default is auto, meaning that the cgi will use
if installed, otherwise revert to
which should always be available on a Debian system. By specifying this
option you can force the use of one of the two program.
Manpage to HTML translation command. Can be
Default is auto, meaning that the cgi will use
if installed, otherwise revert to
By specifying this option you can force the use of one of the two program.
Optional list of one or more
files mapping each file available in the Debian GNU/Linux 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.
background color of the HTML body.
internal option used only for debugging. Disabled by default since it is
useless for normal users.
path on webserver to dwww cgi-bin.
path on webserver to info2www cgi-bin.
The following is an exaple /etc/dpkg-www.conf file:
# Enable install check-buttons in package list.
# Enable install, upgrade and remove buttons in package info.
# List registered package documentation.
# Options passed to grep-dctrl in queryPackagesByField()
# Show local files directly. Automatically set.
# Force ssh passwd prompt even if an ssh agent holds
# the private key.
# List of Contents-xxx.gz files, if available.
# Enable cgi debugging. Not really useful.
The information provided by
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.
If this option is enabled in the
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
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 command to install the requested
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 intalled also on the client side if installing from remote.
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
browser from the Navigator -> 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 Netscape mailcap file:
The dpkg-www WEB installation has been succesfully tested only with
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
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 as root to install or remove
the required packages. Starting this from the WEB could be potentially
vulnerable to man-in-the-middle 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 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 manually. For normal package
maintenance and system upgrade the use of apt-get from the shell is