~ubuntu-branches/ubuntu/precise/devscripts/precise-security

README for Debian devscripts package
====================================

Devscripts provides several scripts which may be of use to Debian
developers.  The following gives a summary of the available scripts --
please read the manpages for full details about the use of these
scripts.  They are contributed by multiple developers; for details of
the authors, please see the code or manpages.

Also, many of these scripts have dependencies on other packages, but
rather than burden the package with a large number of dependencies,
most of which will not be needed by most people, the individual
dependencies are listed as "Recommends" in the control file.  This
ensures that the packages will be installed by default but allows
users to remove them if desired.  The dependencies and recommendations
are listed in square brackets in the description below, as well as in
the Description field in the control file.

And now, in mostly alphabetical order, the scripts:

- annotate-output: prepend time and stream (O for stdout E for sterr)
  for every line of output

- archpath: Prints arch (tla/Bazaar) package names. Also supports
  calculating the package names for other branches.

- bts: A command-line tool for accessing the BTS, both to
  send mails to control@bts.debian.org and to access the web pages and
  SOAP interface of the BTS. [www-browser, libauthen-sasl-perl, 
  libnet-smtp-ssl-perl, libsoap-lite-perl, libwww-perl, bsd-mailx | mailx]

- build-rdeps: Searches for all packages that build-depend on a given package
  [dctrl-tools]

- chdist: A tool to easily play with several distributions. [dctrl-tools]

- checkbashisms: checks whether a /bin/sh script uses any common
  bash-specific features

- cowpoke: upload a Debian source package to a cowbuilder host and build it,
  optionally also signing and uploading the result to an incoming queue 
  [ssh-client]

- cvs-debi, cvs-debc: wrappers around debi and debc respectively (see below)
  which allow them to be called from the CVS working directory.
  [cvs-buildpackage]

- cvs-debrelease: wrapper around debrelease which allows it to be called
  from the CVS working directory. [cvs-buildpackage, dupload | dput, 
  ssh-client]

- cvs-debuild: A wrapper for cvs-buildpackage to use debuild as its package
  building program. [cvs-buildpackage, fakeroot, lintian, gnupg]

- dcmd: Run a given command replacing the name of a .changes or .dsc
  file with each of the files referenced therein 

- dcontrol: Remotely query package and source control files for all Debian
  distributions. [liburl-perl, libwww-perl]

- dd-list: Given a list of packages, pretty-print it ordered by maintainer.

- debc: List contents of current package.  Do this after a successful
  "debuild" to see if the package looks all right.

- debchange (abbreviation dch): Modifies debian/changelog and manages version
  numbers for you.  It will either increment the version number or add a
  entry for the current version, depending upon the options given to it.
  [libparse-debcontrol-perl, libsoap-lite-perl,  lsb-release]

- debcheckout: checkout the development repository of a debian package

- debclean: Clean a Debian source tree.  Debclean will clean all Debian
  source trees below the current directory, and if requested, also remove
  all files that were generated from these source trees (that is .deb, .dsc
  and .changes files).  It will keep the .diffs and original files, though,
  so that the binaries and other files can be rebuilt if necessary.
  [fakeroot]

- debcommit: Commits changes to cvs, darcs, svn, svk, tla, bzr, git, or hg,
  using new entries in debian/changelog as the commit message. Also supports
  tagging Debian package releases. [cvs | darcs | subversion | svk | tla |
  bzr | git-core | mercurial]

- debdiff: A program which examines two .deb files or two .changes files and
  reports on any difference found in their file lists.  Useful for ensuring
  that no files were inadvertantly lost between versions.  Can also examine
  two .dsc files and report on the changes between source versions.
  [wdiff, patchutils]

- debi: Installs the current package by using the setuid root debpkg
  script described below.  It assumes that the current package has
  just been built (for example by debuild), and the .deb lives in the
  parent directory, and will effectively run dpkg -i on the .deb.  The
  ability to install the package with a very short command is very
  useful when troubleshooting packages.

- debpkg: A wrapper for dpkg used by debi to allow convenient testing
  of packages.  For debpkg to work, it needs to be made setuid root,
  and this needs to be performed by the sysadmin -- it is not
  installed as setuid root by default.  (Note that being able to run a
  setuid root debpkg is effectively the same as having root access to
  the system, so this should be done with caution.)  Having debpkg as
  a wrapper for dpkg can be a Good Thing (TM), as it decreases the
  potential for damage by accidental wrong use of commands in
  superuser mode (e.g., an inadvertant rm -rf * in the wrong directory
  is disastrous as many can attest to).

- debrelease: A wrapper around dupload or dput which figures out which
  version to upload, and then calls dupload or dput to actually perform
  the upload. [dupload | dput, ssh-client]

- debrsign: This transfers a .changes/.dsc pair to a remote machine for
  signing, and runs debsign on the remote machine over an SSH connection.
  [gnupg, debian-keyring, ssh-client]

- debsign: Use GNU Privacy Guard to sign the changes (and possibly dsc)
  files created by running dpkg-buildpackage with no-sign options.  Useful
  if you are building a package on a remote machine and wish to sign it on
  a local one.  This script is capable of automatically downloading the
  .changes and .dsc files from a remote machine. [gnupg, debian-keyring, 
  ssh-client]

- debsnap: Grabs packages from http://snapshot.debian.net [wget]

- debuild: A wrapper for building a package (i.e., dpkg-buildpackage) to
  avoid problems with insufficient permissions and wrong paths etc.
  Debuild will set up the proper environment for building a package.
  Debuild will use the fakeroot program to build the package by default, but
  can be instructed to use any other gain-root command, or can even be
  installed setuid root.  Debuild can also be used to run various of
  the debian/rules operations with the same root-gaining procedure.
  Debuild will also run lintian to check that the package does not
  have any major policy violations. [fakeroot, lintian, gnupg]

- deb-reversion: Increases a binary package version number and repacks
  the package, useful for porters and the like.

- desktop2menu: given a freedesktop.org desktop file, generate a skeleton
  for a menu file [libfile-desktopentry-perl]

- dget: Downloads Debian source and binary packages. Point at a .changes or
  .dsc to download all references files. Specify a package name to download
  it from the configured apt repository. [wget | curl]

- diff2patches: Extracts patches from a .diff.gz file placing them under
  debian/ or, if present, debian/patches. [patchutils]

- dpkg-depcheck, dpkg-genbuilddeps: Runs a specified command (such as
  debian/rules build) or dpkg-buildpackage, respectively, to determine the
  packages used during the build process.  This information can be helpful
  when trying to determine the packages needed in the Build-Depends etc.
  lines in the debian/control file. [build-essential, strace]

- dscverify: check the signature and MD5 sums of a dsc file against the most
  current Debian keyring on your system. [gnupg, debian-keyring, 
  libdigest-md5-perl]

- getbuildlog: Download package build logs from Debian auto-builders. [wget]

- grep-excuses: grep the update_excuses.html file to find out what is
  happening to your packages. [libterm-size-perl, wget, w3m]

- licensecheck: given a list of source files, attempt to determine which
  license (or combination of licenses) each file is placed under.

- list-unreleased: searches for packages marked UNRELEASED in their
  changelog

- manpage-alert: locate binaries without corresponding manpages. [man-db]

- mass-bug: mass-file bug reports [bsd-mailx | mailx]

- mergechanges: merge .changes files from the same release but built
  on different architectures.

- mk-build-deps: Given a package name and/or control file, generate a 
  binary package which may be installed to satisfy the build-dependencies
  of the given package. [equivs]

- namecheck: Check project names are not already taken.

- nmudiff: prepare a diff of this version (presumably an NMU against the
  previously released version (as per the changelog) and submit the diff
  to the BTS. [patchutils, mutt]

- plotchangelog: display information from a changelog graphically using
  gnuplot. [libtimedate-perl, gnuplot]

- pts-subscribe: subscribe to the PTS (Package Tracking System) for a
  limited period of time. [bsd-mailx | mailx, at]

- rc-alert: list installed packages which have release-critical bugs [wget]

- rmadison: Remotely query the Debian archive database about packages.
  [liburi-perl, wget | curl]

- svnpath: Prints the path to the suversion repository of a subversion
  checkout. Also supports calculating the paths for branches and
  tags in a repository independent fashion. Used by debcommit to generate
  svn tags. [subversion]

- tagpending: Runs from a Debian source tree and tags bugs that are to be
  closed in the latest changelog as pending. [libsoap-lite-perl]

- transition-check: Check a list of source packages for involvement in
  transitions for which uploads to unstable are currently blocked
  [libwww-perl, libyaml-syck-perl]

- uscan: Automatically scan for and download upstream updates.  Uscan can
  also call a program such as uupdate to attempt to update the Debianised
  version based on the new update.  Whilst uscan could be used to release
  the updated version automatically, it is probably better not to without
  testing it first. [libcrypt-ssleay-perl, libwww-perl, unzip, lzma, xz-utils]

- uupdate: Update the package with an archive or patches from
  an upstream author.  This will be of help if you have to update your
  package.  It will try to apply the latest diffs to your package and
  tell you how successful it was. [patch]

- whodepends: check which maintainers' packages depend on a package

- who-uploads: determine the most recent uploaders of a package to the
  Debian archive [gnupg, debian-keyring, debian-maintainers, wget]

- wnpp-alert: list installed packages which are orphaned or up for adoption
  [wget]

- wnpp-check: check whether there is an open request for packaging or
  intention to package bug for a package [wget]

- /usr/share/doc/devscripts/examples: This directory contains examples of
  procmail and exim scripts for sorting mail arriving to Debian
  mailing lists.

Typical Maintenance cycle with devscripts
-----------------------------------------

1. cd <source directory of package>

2. Editing of files

3. Log the changes with: dch -i "I changed this"
   If desired, use debcommit to commit changes to cvs, svn, arch or git.

4. Run debuild to compile it.  If it fails, return to 2.  (You could
   also just test the compilation by running the appropriate part of
   debian/rules.)

5. Check if package contents appear to be ok with "debc"

6. Install the package with "debi" and test the functionality it
   should provide.  (Note that this step requires debpkg to be setuid
   root, or you to be logged in as root or similar.)

7. If all is ok release it by running debrelease.

8. Optionally, use debcommit --release to commit and tag the release
   in revision control.


Wrapper scripts
---------------

Devscripts includes two wrappers (the above mentioned "debuild" and
"debpkg") that are intended to make life easier for Debian developers.
These wrappers unset most environment variables for security reasons,
set a secure PATH and then run the appropriate program (such as dpkg).
Processing Makefiles is inherently dangerous though, since any UNIX
command can be executed.  The fakeroot command makes it possible to
build a package in a secure way: it does not require any genuine root
access, but rather pretends that it has it.  It is strongly
recommended that you install the "fakeroot" package!  Installation of
a package with dpkg always requires superuser mode and is therefore
inherently dangerous.  Debi aims to reduce the possibility of typos
by only performing a dpkg -i as root.  This does not, however, do
anything for security, as there is no problem creating a package with
a setuid-root shell using fakeroot and then installing it with debpkg.
So only allow trusted users access to a setuid root debpkg, if at all!

The wrappers have to be manually equipped to gain the necessary
privileges to do their jobs because of security concerns.  You have to
equip "debpkg" with superuser privileges.  "debuild" needs superuser
privileges only if fakeroot or another gain-root command is not
available.

You can either:

(a) invoke these wrappers from "sudo" or "super" or any other way you
    have to control superuser access, or

(b) you can set them up to be accessible only to a group of users.
    (Some people suggest that this is highly dangerous since it
    creates another executable that runs with the setuid root bit set
    and which won't ever ask you for a password!)  If you choose this
    method, it can be done by issuing the following command:

      dpkg-statoverride --update --add root root_group 4754 /usr/bin/debpkg

    once (and similarly for debuild if you really need it).  This will
    enable access to debpkg for all users who are members of the group
    "root_group".  Remember that you are in effect giving those users
    superuser access to your system!  This information will be stored
    in the dpkg database and remembered across upgrades.

    Because of the security implications, only do this on your home
    linux box, NOT on a busy internet server (and possibly not even
    there).

Originally by Christoph Lameter <clameter@waterf.org>
Modified extensively by Julian Gilbey <jdg@debian.org>