GNUnet Installation Handbook
****************************

This handbook describes how to install (build setup, compilation) and setup (configuration, start) GNUnet 0.10.x. After following these instructions you should be able to install and then start user-interfaces to interact with the network.

This manual is far from complete, and we welcome informed contributions, be it in the form of new chapters or insightful comments.

Dependencies
============

This section lists the various known dependencies for GNUnet EDITION. Suggestions for missing dependencies or wrong version numbers are welcome.

External dependencies
---------------------

These packages must be installed before a typical GNUnet installation can be performed:

  * autoconf

  * automake

  * pkg-config

  * libltdl

  * gstreamer

  * gst-plugins-base

  * perl

  * python (only 2.7 supported) (tests and gnunet-qr)

  * jansson

  * nss

  * glib

  * gmp

  * bluez

  * miniupnpc

  * gettext

  * which

  * texinfo

  * GNU libmicrohttpd ≥ 0.9.30  (We recommend to build it with a GnuTLS version that was configured with libunbound ("DANE support"))

  * GNU libextractor ≥ 1.0

  * GNU libtool ≥ 2.2

  * GNU libunistring ≥ 0.9.1.1

  * GNU libidn ≥ 1.0.0

  * GNU libgcrypt (https://gnupg.org/software/libgcrypt/) ≥ 1.6.0 (https://gnupg.org/ftp/gcrypt/libgcrypt/)

  * GnuTLS (https://gnutls.org/) ≥ 3.2.7 (We recommend to compile with libunbound for DANE support; GnuTLS also requires GNU nettle 2.7 (update: GnuTLS 3.2.7 appears NOT to work against GNU nettle > 2.7, due to some API updatings done by nettle. Thus it should be compiled against nettle 2.7 and, in case you get some error on the reference to `rpl_strerror' being undefined, follow the instructions on this (http://lists.gnupg.org/pipermail/gnutls-devel/2013-November/006588.html) post (and the link inside it)).)

  * gnURL (https://gnunet.org/gnurl) libgnurl ≥ 7.34.0 (must be compiled after GnuTLS)

  * libglpk ≥ 4.45

  * OpenSSL (http://www.openssl.org/) ≥ 1.0

  * TeX Live ≥ 2012, optional (for gnunet-bcd)

  * Texinfo ≥ 5.2 (for documentation)

  * libsqlite ≥ 3.8.0  ((note that the code will compile and often work with lower version numbers, but you may get subtle bugs with respect to quota management in certain rare cases); alternatively, MySQL or Postgres can also be installed, but those databases will require more complex configurations (not recommended for first-time users))

  * zlib

Fixing libgnurl build issues
----------------------------

If you have to compile libgnurl from source since the version included in your distribution is to old you perhaps get an error message while running the configure script:

     $ configure
     ...
     checking for 64-bit curl_off_t data type... unknown
     checking for 32-bit curl_off_t data type... unknown
     checking for 16-bit curl_off_t data type... unknown
     configure: error: cannot find data type for curl_off_t.

Solution:

Before running the configure script, set:

     CFLAGS="-I. -I$BUILD_ROOT/include"

Optional dependencies
---------------------

These applications must be installed for various experimental or otherwise optional features such as gnunet-conversation, gnunet-gtk.

  * libpulse 2.0 or higher, optional (for gnunet-conversation)

  * libopus 1.0.1 or higher, optional (for gnunet-conversation)

  * libogg 1.3.0 or higher, optional (for gnunet-conversation)

  * certool (binary) optional  (for convenient installation of the GNS proxy (available as part of Debian's libnss3-tools))

  * python-zbar 0.10 or higher, optional (for gnunet-qr)

  * Gtk+ 3.0 or higher, optional (for gnunet-gtk)

  * libgladeui must match Gtk+ version, optional (for gnunet-gtk)

  * libqrencode 3.0 or higher, optional (for gnunet-namestore-gtk)

Internal dependencies
---------------------

This section tries to give an overview of what processes a typical GNUnet peer running a particular application would consist of. All of the processes listed here should be automatically started by gnunet-arm -s. The list is given as a rough first guide to users for failure diagnostics. Ideally, end-users should never have to worry about these internal dependencies.

In terms of internal dependencies, a minimum file-sharing system consists of the following GNUnet processes (in order of dependency):

  * gnunet-service-arm

  * gnunet-service-resolver (required by all)

  * gnunet-service-statistics (required by all)

  * gnunet-service-peerinfo

  * gnunet-service-transport (requires peerinfo)

  * gnunet-service-core (requires transport)

  * gnunet-daemon-hostlist (requires core)

  * gnunet-daemon-topology (requires hostlist, peerinfo)

  * gnunet-service-datastore

  * gnunet-service-dht (requires core)

  * gnunet-service-identity

  * gnunet-service-fs (requires identity, mesh, dht, datastore, core)

A minimum VPN system consists of the following GNUnet processes (in order of dependency):

  * gnunet-service-arm

  * gnunet-service-resolver (required by all)

  * gnunet-service-statistics (required by all)

  * gnunet-service-peerinfo

  * gnunet-service-transport (requires peerinfo)

  * gnunet-service-core (requires transport)

  * gnunet-daemon-hostlist (requires core)

  * gnunet-service-dht (requires core)

  * gnunet-service-mesh (requires dht, core)

  * gnunet-service-dns (requires dht)

  * gnunet-service-regex (requires dht)

  * gnunet-service-vpn (requires regex, dns, mesh, dht)

A minimum GNS system consists of the following GNUnet processes (in order of dependency):

  * gnunet-service-arm

  * gnunet-service-resolver (required by all)

  * gnunet-service-statistics (required by all)

  * gnunet-service-peerinfo

  * gnunet-service-transport (requires peerinfo)

  * gnunet-service-core (requires transport)

  * gnunet-daemon-hostlist (requires core)

  * gnunet-service-dht (requires core)

  * gnunet-service-mesh (requires dht, core)

  * gnunet-service-dns (requires dht)

  * gnunet-service-regex (requires dht)

  * gnunet-service-vpn (requires regex, dns, mesh, dht)

  * gnunet-service-identity

  * gnunet-service-namestore (requires identity)

  * gnunet-service-gns (requires vpn, dns, dht, namestore, identity)

Pre-installation notes
======================

Please note that in the code instructions for the installation, # indicates commands run as privileged root user and $ shows commands run as unprivileged ("normal") system user.

Generic installation instructions
=================================

First, in addition to the GNUnet sources you must download the latest version of various dependencies. Most distributions do not include sufficiently recent versions of these dependencies. Thus, a typically installation on a "modern" GNU/Linux distribution requires you to install the following dependencies (ideally in this order):

  * libgpgerror and libgcrypt

  * libnettle and libunbound (possibly from distribution), GnuTLS

  * libgnurl (read the README)

  * GNU libmicrohttpd

  * GNU libextractor

Make sure to first install the various mandatory and optional dependencies including development headers from your distribution.

Other dependencies that you should strongly consider to install is a database (MySQL, sqlite or Postgres). The following instructions will assume that you installed at least sqlite. For most distributions you should be able to find pre-build packages for the database. Again, make sure to install the client libraries and the respective development headers (if they are packaged separately) as well.

You can find specific, detailed instructions for installing of the dependencies (and possibly the rest of the GNUnet installation) in the platform-specific descriptions, which are linked from the bottom of this page. Please consult them now. If your distribution is not listed, please study the instructions for Debian stable carefully as you try to install the dependencies for your own distribution. Contributing additional instructions for further platforms is always appreciated.

Before proceeding further, please double-check the dependency list. Note that in addition to satisfying the dependencies, you might have to make sure that development headers for the various libraries are also installed. There maybe files for other distributions, or you might be able to find equivalent packages for your distribution.

While it is possible to build and install GNUnet without having root access, we will assume that you have full control over your system in these instructions. First, you should create a system user gnunet and an additional group gnunetdns. On Debian and Ubuntu GNU/Linux, type:

     # adduser --system --home /var/lib/gnunet --group \
     --disabled-password gnunet
     # addgroup --system gnunetdns

On other Unixes, this should have the same effect:

     # useradd --system --groups gnunet --home-dir /var/lib/gnunet
     # addgroup --system gnunetdns

Now compile and install GNUnet using:

     $ tar xvf gnunet-0.10.?.tar.gz
     $ cd gnunet-0.10.?
     $ ./configure --with-sudo=sudo --with-nssdir=/lib
     $ make
     $ sudo make install

If you want to be able to enable DEBUG-level log messages, add --enable-logging=verbose to the end of the ./configure command. DEBUG-level log messages are in English-only and should only be useful for developers (or for filing really detailed bug reports).

Finally, you probably want to compile gnunet-gtk, which includes gnunet-setup (graphical tool for configuration) and gnunet-fs-gtk (graphical tool for file-sharing):

     $ tar xvf gnunet-gtk-0.10.?.tar.gz
     $ cd gnunet-gtk-0.10.?
     $ ./configure --with-gnunet=/usr/local/
     $ make
     $ sudo make install
     $ cd ..
     $ sudo ldconfig # just to be safe

Next, edit the file /etc/gnunet.conf to contain the following:

     [arm]
     SYSTEM_ONLY = YES
     USER_ONLY = NO

You may need to update your ld.so cache to include files installed in /usr/local/lib:  # ldconfig .

Then, switch from user root to user gnunet to start the peer:

     # su -s /bin/sh - gnunet
     $ gnunet-arm -c /etc/gnunet.conf -s

You may also want to add the last line in the gnunet users crontab prefixed with @reboot so that it is executed whenever the system is booted:

     @reboot /usr/local/bin/gnunet-arm -c /etc/gnunet.conf -s

This will only start the system-wide GNUnet services. Type exit to get back your root shell. Now, you need to configure the per-user part. For each $USER on the system, run:  # adduser $USER gnunet .

to allow them to access the system-wide GNUnet services. Then, each user should create a configuration file ~/.config/gnunet.conf with the lines:

     [arm]
     SYSTEM_ONLY = NO
     USER_ONLY = YES
     DEFAULTSERVICES = gns

and start the per-user services using

$ gnunet-arm -c ~/.config/gnunet.conf -s

Again, adding a crontab entry to autostart the peer is advised:

@reboot /usr/local/bin/gnunet-arm -c $HOME/.config/gnunet.conf -s

Note that some GNUnet services (such as SOCKS5 proxies) may need a system-wide TCP port for each user. For those services, systems with more than one user may require each user to specify a different port number in their personal configuration file.

Finally, the user should perform the basic initial setup for the GNU Name System. This is done by running two commands:

     $ gnunet-gns-import.sh
     $ gnunet-gns-proxy-setup-ca

The first generates the default zones, wheras the second setups the GNS Certificate Authority with the user's browser. Now, to actiave GNS in the normal DNS resolution process, you need to edit your /etc/nsswitch.conf where you should find a line like this:

     hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4

The exact details may differ a bit, which is fine. Add the text "gns [NOTFOUND=return]" after "files":

     hosts: files gns [NOTFOUND=return] mdns4_minimal [NOTFOUND=return] dns mdns4

You might want to make sure that /lib/libnss_gns.so.2 exists on your system, it should have been created during the installation.

Build instructions for Ubuntu 12.04 using Git
=============================================

Install the required build tools
--------------------------------

First, make sure Git is installed on your system:

     $ sudo apt-get install git

Install the essential buildtools:

     $ sudo apt-get install automake autopoint autoconf libtool

Install libgcrypt 1.6 and libgpg-error
--------------------------------------

     $ wget ftp://ftp.gnupg.org/gcrypt/libgpg-error/libgpg-error-1.12.tar.bz2
     $ tar xf libgpg-error-1.12.tar.bz2
     $ cd libgpg-error-1.12
     $ ./configure
     $ sudo make install ; cd ..

Install gnutls with DANE support
--------------------------------

     $ wget http://www.lysator.liu.se/~nisse/archive/nettle-2.7.1.tar.gz
     $ tar xf nettle-2.7.1.tar.gz
     $ cd nettle-2.7.1
     $ ./configure
     $ sudo make install ; cd ..

     $ wget https://www.nlnetlabs.nl/downloads/ldns/ldns-1.6.16.tar.gz
     $ tar xf ldns-1.6.16.tar.gz
     $ cd ldns-1.6.16
     $ ./configure
     $ sudo make install ; cd ..

     $ wget https://unbound.net/downloads/unbound-1.4.21.tar.gz
     $ tar xf unbound-1.4.21.tar.gz
     $ cd unbound-1.4.21
     $ ./configure
     $ sudo make install ; cd ..

     $ wget ftp://ftp.gnutls.org/gcrypt/gnutls/v3.1/gnutls-3.1.17.tar.xz
     $ tar xf gnutls-3.1.17.tar.xz
     $ cd gnutls-3.1.17
     $ ./configure
     $ sudo make install ; cd ..

     $ wget ftp://ftp.gnupg.org/gcrypt/libgcrypt/libgcrypt-1.6.0.tar.bz2
     $ tar xf libgcrypt-1.6.0.tar.bz2
     $ cd libgcrypt-1.6.0
     $ ./configure
     $ sudo make install ; cd ..

Install libgnurl
----------------

     $ wget https://gnunet.org/sites/default/files/gnurl-7.34.0.tar.bz2
     $ tar xf gnurl-7.34.0.tar.bz2
     $ cd gnurl-7.34.0
     $ ./configure --enable-ipv6 --with-gnutls --without-libssh2 \
       --without-libmetalink --without-winidn --without-librtmp \
       --without-nghttp2 --without-nss --without-cyassl \
       --without-polarssl --without-ssl --without-winssl \
       --without-darwinssl --disable-sspi --disable-ntlm-wb \
       --disable-ldap --disable-rtsp --disable-dict --disable-telnet \
       --disable-tftp --disable-pop3 --disable-imap --disable-smtp \
       --disable-gopher --disable-file --disable-ftp
     $ sudo make install ; cd ..

Install libmicrohttpd from Git
------------------------------

     $ git clone https://gnunet.org/git/libmicrohttpd
     $ cd libmicrohttpd/
     $ ./bootstrap
     $ ./configure
     $ sudo make install ; cd ..

Install libextractor from Git
-----------------------------

Install libextractor dependencies:

     $ sudo apt-get install zlib1g-dev libgsf-1-dev libmpeg2-4-dev \
      libpoppler-dev libvorbis-dev libexiv2-dev libjpeg-dev \
      libtiff-dev libgif-dev libvorbis-dev libflac-dev libsmf-dev \
      g++

Build libextractor:

     $ git clone https://gnunet.org/git/libextractor
     $ cd libextractor
     $ ./bootstrap
     $ ./configure
     $ sudo make install ; cd ..

Install GNUnet dependencies
---------------------------

     $ sudo apt-get install libidn11-dev libunistring-dev libglpk-dev \
      libpulse-dev libbluetooth-dev libsqlite-dev

Install libopus:

     $ wget http://downloads.xiph.org/releases/opus/opus-1.1.tar.gz
     $ tar xf opus-1.1.tar.gz
     $ cd opus-1.1/
     $ ./configure
     $ sudo make install ; cd ..

Choose one or more database backends:

SQLite3:

     $ sudo apt-get install libsqlite3-dev

MySQL:

     $ sudo apt-get install libmysqlclient-dev

PostgreSQL:

     $ sudo apt-get install libpq-dev postgresql

Build GNUnet
------------

Configuring the installation path
.................................

You can specify the location of the GNUnet installation by setting the prefix when calling the configure script with --prefix=DIRECTORY

     $ export PATH=$PATH:DIRECTORY/bin

Configuring the system
......................

Please make sure NOW that you have created a user and group 'gnunet' and additionally a group 'gnunetdns':

     $ sudo addgroup gnunet
     $ sudo addgroup gnunetdns
     $ sudo adduser gnunet

Each GNUnet user should be added to the 'gnunet' group (may require fresh login to come into effect):

     $ sudo useradd -G  gnunet

Installing components requiring sudo permission
...............................................

Some components, like the nss plugin required for GNS, may require root permissions. To allow these few components to be installed use:

     $ ./configure --with-sudo

Build
.....

     $ git clone https://gnunet.org/git/gnunet/
     $ cd gnunet/
     $ ./bootstrap

Use the required configure call including the optional installation prefix PREFIX or the sudo permissions:

     $ ./configure [ --with-sudo | --with-prefix=PREFIX ]

     $ make; sudo make install

After installing it, you need to create an empty configuration file:

     mkdir ~/.gnunet; touch ~/.gnunet/gnunet.conf

And finally you can start GNUnet with $ gnunet-arm -s.

Install the GNUnet-gtk user interface from Git
----------------------------------------------

Install depencies:

     $ sudo apt-get install libgtk-3-dev libunique-3.0-dev libgladeui-dev \
     libqrencode-dev

To build GNUnet (with an optional prefix)and execute:

     $ git clone https://gnunet.org/git/gnunet-gtk/
     $ cd gnunet-gtk/
     $ ./bootstrap
     $ ./configure [--prefix=PREFIX] --with-gnunet=DIRECTORY
     $ make; sudo make install

Build Instructions for Microsoft Windows Platforms
==================================================

Introduction to building on MS Windows
--------------------------------------

This document is a guide to building GNUnet and its dependencies on Windows platforms. GNUnet development is mostly done under Linux and especially SVN checkouts may not build out of the box. We regret any inconvenience, and if you have problems, please report them.

Requirements
------------

The Howto is based upon a Windows Server 2008 32bit Installation, sbuild and thus a MSYS+MinGW (http://www.mingw.org/wiki/MSYS) (W32-GCC-Compiler-Suite + Unix-like Userland) installation. sbuild is a convenient set of scripts which creates a working msys/mingw installation and installs most dependencies required for GNUnet.

As of the point of the creation of this Howto, GNUnet requires a Windows Server 2003 or newer for full feature support. Windows Vista and later will also work, but non-server version can not run a VPN-Exit-Node as the NAT features have been removed as of Windows Vista.

Dependencies & Initial Setup
----------------------------

  * Install a fresh version of Python 2.x, even if you are using a x64-OS, install a 32-bit version for use with sbuild. Python 3.0 currently is incompatible.

  * Install your favorite GIT (http://code.google.com/p/tortoisegit/) & SVN (http://tortoisesvn.net/)-clients.

  * You will also need some archive-manager like 7zip (http://www.7-zip.org/).

  * Pull a copy of sbuild to a directory of your choice, which will be used in the remainder of this guide. For now, we will use c:\gnunet\sbuild\

  * in sbuild\src\mingw\mingw32-buildall.sh, comment out the packages gnunet-svn and gnunet-gtk-svn, as we don't want sbuild to compile/install those for us.

  * Follow LRN's sbuild installation instructions.-

Please note that sbuild may (or will most likely) fail during installation, thus you really HAVE to check the logfiles created during the installation process. Certain packages may fail to build initially due to missing dependencies, thus you may have to substitute those with binary-versions initially. Later on once dependencies are satisfied you can re-build the newer package versions.

It is normal that you may have to repeat this step multiple times and there is no uniform way to fix all compile-time issues, as the build-process of many of the dependencies installed are rather unstable on win32 and certain releases may not even compile at all.

Most dependencies for GNUnet have been set up by sbuild, thus we now should add the bin/ directories in your new msys and mingw installations to PATH. You will want to create a backup of your finished msys-environment by now.

GNUnet Installation
-------------------

First, we need to launch our msys-shell, you can do this via

C:\gnunet\sbuild\msys\msys.bat

You might wish to take a look at this file and adjust some login-parameters to your msys environment.

Also, sbuild added two pointpoints to your msys-environment, though those might remain invisible:

  * /mingw, which will mount your mingw-directory from sbuild/mingw and the other one is

  * /src which contains all the installation sources sbuild just compiled.

Check out the current gnunet-sources (svn-head) from the gnunet-repository, we will do this in your home directory:

svn checkout https://gnunet.org/svn/gnunet/ ~/gnunet

Now, we will first need to bootstrap the checked out installation and then configure it accordingly.

     cd ~/gnunet
     ./bootstrap
     STRIP=true CPPFLAGS="-DUSE_IPV6=1 -DW32_VEH" CFLAGS="$CFLAGS -g -O2" \
     ./configure --prefix=/ --docdir=/share/doc/gnunet \
     --with-libiconv-prefix=/mingw --with-libintl-prefix=/mingw \
     --with-libcurl=/mingw --with-extractor=/mingw --with-sqlite=/mingw \
     --with-microhttpd=/mingw --with-plibc=/mingw --enable-benchmarks \
     --enable-expensivetests --enable-experimental --with-qrencode=/mingw \
     --enable-silent-rules --enable-experimental 2>&1 | tee -a ./configure.log

The parameters above will configure for a reasonable gnunet installation to the your msys-root directory. Depending on which features your would like to build or you may need to specify additional dependencies. Sbuild installed most libs into the /mingw subdirectory, so remember to prefix library locations with this path.

Like on a unixoid system, you might want to use your home directory as prefix for your own gnunet installation for development, without tainting the buildenvironment. Just change the "prefix" parameter to point towards ~/ in this case.

Now it's time to compile gnunet as usual. Though this will take some time, so you may fetch yourself a coffee or some Mate now...

     make ; make install

Adjusting Windows for running and testing GNUnet
------------------------------------------------

Assuming the build succeeded and you added the bin directory of your gnunet to PATH, you can now use your gnunet-installation as usual. Remember that UAC or the windows firewall may popup initially, blocking further execution of gnunet until you acknowledge them (duh!).

You will also have to take the usual steps to get p2p software running properly (port forwarding, ...), and gnunet will require administrative permissions as it may even install a device-driver (in case you are using gnunet-vpn and/or gnunet-exit).

Building the GNUnet Installer
-----------------------------

The GNUnet installer is made with NSIS (http://nsis.sourceforge.net/) The installer script is located in contrib\win in the GNUnet source tree.

Using GNUnet with Netbeans on Windows
-------------------------------------

TODO

Build instructions for Debian 7.5
=================================

These are the installation instructions for Debian 7.5. They were tested using a minimal, fresh Debian 7.5 AMD64 installation without non-free software (no contrib or non-free). By "minimal", we mean that during installation, we did not select any desktop environment, servers or system utilities during the "tasksel" step. Note that the packages and the dependencies that we will install during this chapter take about 1.5 GB of disk space. Combined with GNUnet and space for objects during compilation, you should not even attempt this unless you have about 2.5 GB free after the minimal Debian installation. Using these instructions to build a VM image is likely to require a minimum of 4-5 GB for the VM (as you will likely also want a desktop manager).

GNUnet's security model assumes that your /home directory is encrypted. Thus, if possible, you should encrypt your home partition (or per-user home directory).

Naturally, the exact details of the starting state for your installation should not matter much. For example, if you selected any of those installation groups you might simply already have some of the necessary packages installed. We did this for testing, as this way we are less likely to forget to mention a required package. Note that we will not install a desktop environment, but of course you will need to install one to use GNUnet's graphical user interfaces. Thus, it is suggested that you simply install the desktop environment of your choice before beginning with the instructions.

Update
------

After any installation, you should begin by running

     # apt-get update ; apt-get upgrade

to ensure that all of your packages are up-to-date. Note that the "#" is used to indicate that you need to type in this command as "root" (or prefix with "sudo"), whereas "$" is used to indicate typing in a command as a normal user.

Stable? Hah!
------------

Yes, we said we start with a Debian 7.5 "stable" system. However, to reduce the amount of compilation by hand, we will begin by allowing the installation of packages from the testing and unstable distributions as well. We will stick to "stable" packages where possible, but some packages will be taken from the other distributions. Start by modifying /etc/apt/sources.list to contain the following (possibly adjusted to point to your mirror of choice):

     # These were there before:
     deb http://ftp.de.debian.org/debian/ wheezy main
     deb-src http://ftp.de.debian.org/debian/ wheezy main
     deb http://security.debian.org/ wheezy/updates main
     deb-src http://security.debian.org/ wheezy/updates main
     deb http://ftp.de.debian.org/debian/ wheezy-updates main
     deb-src http://ftp.de.debian.org/debian/ wheezy-updates main

     # Add these lines (feel free to adjust the mirror):
     deb http://ftp.de.debian.org/debian/ testing main
     deb http://ftp.de.debian.org/debian/ unstable main

The next step is to create/edit your /etc/apt/preferences file to look like this:

     Package: *
     Pin: release a=stable,n=wheezy
     Pin-Priority: 700

     Package: *
     Pin: release o=Debian,a=testing
     Pin-Priority: 650

     Package: *
     Pin: release o=Debian,a=unstable
     Pin-Priority: 600

You can read more about Apt Preferences here and here. Note that other pinnings are likely to also work for GNUnet, the key thing is that you need some packages from unstable (as shown below). However, as unstable is unlikely to be comprehensive (missing packages) or might be problematic (crashing packages), you probably want others from stable and/or testing.

Update again
------------

Now, run again

     # apt-get update
     # apt-get upgrade

to ensure that all your new distribution indices are downloaded, and that your pinning is correct: the upgrade step should cause no changes at all.

Installing packages
-------------------

We begin by installing a few Debian packages from stable:

     # apt-get install gcc make python-zbar libltdl-dev libsqlite3-dev \
       libunistring-dev libopus-dev libpulse-dev openssl libglpk-dev \
       texlive libidn11-dev libmysqlclient-dev libpq-dev libarchive-dev \
       libbz2-dev libexiv2-dev libflac-dev libgif-dev libglib2.0-dev \
       libgtk-3-dev libmagic-dev libjpeg8-dev libmpeg2-4-dev libmp4v2-dev \
       librpm-dev libsmf-dev libtidy-dev libtiff5-dev libvorbis-dev \
       libogg-dev zlib1g-dev g++ gettext libgsf-1-dev libunbound-dev \
       libqrencode-dev libgladeui-dev nasm texlive-latex-extra \
       libunique-3.0-dev gawk miniupnpc libfuse-dev libbluetooth-dev

After that, we install a few more packages from unstable:

     # apt-get install -t unstable nettle-dev libgstreamer1.0-dev \
       gstreamer1.0-plugins-base gstreamer1.0-plugins-good \
       libgstreamer-plugins-base1.0-dev

Installing dependencies from source
-----------------------------------

Next, we need to install a few dependencies from source. You might want to do this as a "normal" user and only run the make install steps as root (hence the sudo in the commands below). Also, you do this from any directory. We begin by downloading all dependencies, then extracting the sources, and finally compiling and installing the libraries:

     $ wget https://libav.org/releases/libav-9.10.tar.xz
     $ wget http://ftp.gnu.org/gnu/libextractor/libextractor-1.3.tar.gz
     $ wget ftp://ftp.gnupg.org/gcrypt/libgpg-error/libgpg-error-1.12.tar.bz2
     $ wget ftp://ftp.gnupg.org/gcrypt/libgcrypt/libgcrypt-1.6.0.tar.bz2
     $ wget ftp://ftp.gnutls.org/gcrypt/gnutls/v3.2/gnutls-3.2.7.tar.xz
     $ wget http://ftp.gnu.org/gnu/libmicrohttpd/libmicrohttpd-0.9.33.tar.gz
     $ wget https://gnunet.org/sites/default/files/gnurl-7.34.0.tar.bz2
     $ tar xvf libextractor-1.3.tar.gz
     $ tar xvf libgpg-error-1.12.tar.bz2
     $ tar xvf libgcrypt-1.6.0.tar.bz2
     $ tar xvf gnutls-3.2.7.tar.xz
     $ tar xvf libmicrohttpd-0.9.33.tar.gz
     $ tar xvf gnurl-7.34.0.tar.bz2
     $ cd libav-0.9 ; ./configure --enable-shared;
     $ make; sudo make install; cd ..
     $ cd libextractor-1.3 ; ./configure;
     $ make ; sudo make install; cd ..
     $ cd libgpg-error-1.12; ./configure;
     $ make ; sudo make install; cd ..
     $ cd libgcrypt-1.6.0; ./configure --with-gpg-error-prefix=/usr/local;
     $ make ; sudo make install ; cd ..
     $ cd gnutls-3.2.7 ; ./configure;
     $ make ; sudo make install ; cd ..
     $ cd libmicrohttpd-0.9.33; ./configure;
     $ make ; sudo make install ; cd ..
     $ cd gnurl-7.34.0
     $ ./configure --enable-ipv6 --with-gnutls=/usr/local --without-libssh2 \
      --without-libmetalink --without-winidn --without-librtmp --without-nghttp2 \
      --without-nss --without-cyassl --without-polarssl --without-ssl \
      --without-winssl --without-darwinssl --disable-sspi --disable-ntlm-wb \
      --disable-ldap --disable-rtsp --disable-dict --disable-telnet --disable-tftp \
      --disable-pop3 --disable-imap --disable-smtp --disable-gopher --disable-file \
      --disable-ftp
     $ make ; sudo make install; cd ..

Installing GNUnet from source
-----------------------------

For this, simply follow the generic installation instructions from here.

But wait there is more!
-----------------------

So far, we installed all of the packages and dependencies required to ensure that all of GNUnet would be built. However, while for example the plugins to interact with the MySQL or Postgres databases have been created, we did not actually install or configure those databases. Thus, you will need to install and configure those databases or stick with the default Sqlite database. Sqlite is usually fine for most applications, but MySQL can offer better performance and Postgres better resillience.

Installing GNUnet from Git on Ubuntu 14.4
=========================================

Install the required build tools: $ sudo apt-get install git automake autopoint autoconf

Install the required dependencies

     $ sudo apt-get install libltdl-dev libgpg-error-dev libidn11-dev \
      libunistring-dev libglpk-dev libbluetooth-dev libextractor-dev \
      libmicrohttpd-dev libgnutls28-dev

Choose one or more database backends

SQLite3:

     $ sudo apt-get install libsqlite3-dev

MySQL:

     $ sudo apt-get install libmysqlclient-dev

PostgreSQL:

     $ sudo apt-get install libpq-dev postgresql

Install the optional dependencies for gnunet-conversation:

     $ sudo apt-get install gstreamer1.0 libpulse-dev libopus-dev

Install the libgrypt 1.6.1: For Ubuntu 14.04:

     $ sudo apt-get install libgcrypt20-dev

For Ubuntu older 14.04:

     $ wget ftp://ftp.gnupg.org/gcrypt/libgcrypt/libgcrypt-1.6.1.tar.bz2
     $ tar xf libgcrypt-1.6.1.tar.bz2
     $ cd libgcrypt-1.6.1
     $ ./configure
     $ sudo make install
     $ cd ..

Install libgnurl

     $ wget https://gnunet.org/sites/default/files/gnurl-7.35.0.tar.bz2
     $ tar xf gnurl-7.35.0.tar.bz2
     $ cd gnurl-7.35.0
     $ ./configure --enable-ipv6 --with-gnutls --without-libssh2 \
      --without-libmetalink --without-winidn --without-librtmp --without-nghttp2 \
      --without-nss --without-cyassl --without-polarssl --without-ssl \
      --without-winssl --without-darwinssl --disable-sspi --disable-ntlm-wb \
      --disable-ldap --disable-rtsp --disable-dict --disable-telnet --disable-tftp \
      --disable-pop3 --disable-imap --disable-smtp --disable-gopher --disable-file \
      --disable-ftp
     $ sudo make install
     $ cd ..

Install GNUnet

     $ git clone https://gnunet.org/git/gnunet/
     $ cd gnunet/
     $ ./bootstrap

If you want to:

  * Install to a different directory: --prefix=PREFIX

  * Have sudo permission, but do not want to compile as root: --with-sudo

  * Want debug message enabled: -- enable-logging=verbose

$ ./configure [ --with-sudo | --prefix=PREFIX | --- enable-logging=verbose] $ make; sudo make install

After installing it, you need to create an empty configuration file: touch ~/.config/gnunet.conf

And finally you can start GNUnet with $ gnunet-arm -s

Build instructions for Debian 8
===============================

These are the installation instructions for Debian 8. They were tested using a fresh Debian 8 AMD64 installation without non-free software (no contrib or non-free). During installation, I only selected "lxde" for the desktop environment. Note that the packages and the dependencies that we will install during this chapter take about 1.5 GB of disk space. Combined with GNUnet and space for objects during compilation, you should not even attempt this unless you have about 2.5 GB free after the Debian installation. Using these instructions to build a VM image is likely to require a minimum of 4-5 GB for the VM (as you will likely also want a desktop manager).

GNUnet's security model assumes that your /home directory is encrypted. Thus, if possible, you should encrypt your entire disk, or at least just your home partition (or per-user home directory).

Naturally, the exact details of the starting state for your installation should not matter much. For example, if you selected any of those installation groups you might simply already have some of the necessary packages installed. Thus, it is suggested that you simply install the desktop environment of your choice before beginning with the instructions.

Update Debian
-------------

After any installation, you should begin by running

# apt-get update # apt-get upgrade

to ensure that all of your packages are up-to-date. Note that the "#" is used to indicate that you need to type in this command as "root" (or prefix with "sudo"), whereas "$" is used to indicate typing in a command as a normal user.

Installing Debian Packages
--------------------------

We begin by installing a few Debian packages from stable:

      # apt-get install gcc make python-zbar libltdl-dev libsqlite3-dev \
       libunistring-dev libopus-dev libpulse-dev openssl libglpk-dev texlive \
       libidn11-dev libmysqlclient-dev libpq-dev libarchive-dev libbz2-dev \
       libflac-dev libgif-dev libglib2.0-dev libgtk-3-dev libmpeg2-4-dev \
       libtidy-dev libvorbis-dev libogg-dev zlib1g-dev g++ gettext libgsf-1-dev \
       libunbound-dev libqrencode-dev libgladeui-dev nasm texlive-latex-extra \
       libunique-3.0-dev gawk miniupnpc libfuse-dev libbluetooth-dev \
       gstreamer1.0-plugins-base gstreamer1.0-plugins-good \
       libgstreamer-plugins-base1.0-dev nettle-dev libextractor-dev libgcrypt20-dev \
       libmicrohttpd-dev

Installing Dependencies from Source2
------------------------------------

Yes, we said we start with a Debian 8 "stable" system, but because Debian linked GnuTLS without support for DANE, we need to compile a few things, in addition to GNUnet, still by hand. Yes, you can run GNUnet using the respective Debian packages, but then you will not get DANE support.

Next, we need to install a few dependencies from source. You might want to do this as a "normal" user and only run the make install steps as root (hence the sudo in the commands below). Also, you do this from any directory. We begin by downloading all dependencies, then extracting the sources, and finally compiling and installing the libraries:

$ wget ftp://ftp.gnutls.org/gcrypt/gnutls/v3.3/gnutls-3.3.12.tar.xz $ wget https://gnunet.org/sites/default/files/gnurl-7.40.0.tar.bz2 $ tar xvf gnutls-3.3.12.tar.xz $ tar xvf gnurl-7.40.0.tar.bz2 $ cd gnutls-3.3.12 ; ./configure ; make ; sudo make install ; cd .. $ cd gnurl-7.40.0 $ ./configure --enable-ipv6 --with-gnutls=/usr/local --without-libssh2 \ --without-libmetalink --without-winidn --without-librtmp --without-nghttp2 \ --without-nss --without-cyassl --without-polarssl --without-ssl \ --without-winssl --without-darwinssl --disable-sspi --disable-ntlm-wb \ --disable-ldap --disable-rtsp --disable-dict --disable-telnet --disable-tftp \ --disable-pop3 --disable-imap --disable-smtp --disable-gopher --disable-file \ --disable-ftp --disable-smb $ make ; sudo make install; cd ..

Installing GNUnet from Source2
------------------------------

For this, simply follow the generic installation instructions from here.

But wait (again) there is more!
-------------------------------

So far, we installed all of the packages and dependencies required to ensure that all of GNUnet would be built. However, while for example the plugins to interact with the MySQL or Postgres databases have been created, we did not actually install or configure those databases. Thus, you will need to install and configure those databases or stick with the default Sqlite database. Sqlite is usually fine for most applications, but MySQL can offer better performance and Postgres better resillience.

Outdated build instructions for previous revisions
==================================================

This chapter contains a collection of outdated, older installation guides. They are mostly intended to serve as a starting point for writing up-to-date instructions and should not be expected to work for GNUnet 0.10.x. A set of older installation instructions can also be found in the doc/outdated-and-old-installation-instructions.txt in the source of GNUnet. This file covers old instructions which no longer receive security updates or any kind of support.

Installing GNUnet 0.10.1 on Ubuntu 14.04
----------------------------------------

Install the required dependencies

     $ sudo apt-get install libltdl-dev libgpg-error-dev libidn11-dev \
       libunistring-dev libglpk-dev libbluetooth-dev libextractor-dev \
       libmicrohttpd-dev libgnutls28-dev

Choose one or more database backends SQLite3

$ sudo apt-get install libsqlite3-dev

MySQL

$ sudo apt-get install libmysqlclient-dev

PostgreSQL

$ sudo apt-get install libpq-dev postgresql

Install the optional dependencies for gnunet-conversation:

$ sudo apt-get install gstreamer1.0 libpulse-dev libopus-dev

Install the libgrypt 1.6: For Ubuntu 14.04: $ sudo apt-get install libgcrypt20-dev For Ubuntu older 14.04: $ wget ftp://ftp.gnupg.org/gcrypt/libgcrypt/libgcrypt-1.6.1.tar.bz2 $ tar xf libgcrypt-1.6.1.tar.bz2 $ cd libgcrypt-1.6.1 $ ./configure $ sudo make install $ cd ..

Install libgnurl

      $ wget https://gnunet.org/sites/default/files/gnurl-7.35.0.tar.bz2
      $ tar xf gnurl-7.35.0.tar.bz2
      $ cd gnurl-7.35.0
      $ ./configure --enable-ipv6 --with-gnutls --without-libssh2 \
      --without-libmetalink --without-winidn --without-librtmp --without-nghttp2 \
      --without-nss --without-cyassl --without-polarssl --without-ssl \
      --without-winssl --without-darwinssl --disable-sspi --disable-ntlm-wb \
      --disable-ldap --disable-rtsp --disable-dict --disable-telnet --disable-tftp \
      --disable-pop3 --disable-imap --disable-smtp --disable-gopher --disable-file \
      --disable-ftp
      $ sudo make install
      $ cd ..

Install GNUnet

$ wget http://ftpmirror.gnu.org/gnunet/gnunet-0.10.1.tar.gz $ tar xf gnunet-0.10.1.tar.gz $ cd gnunet-0.10.1

If you want to:

  * Install to a different directory: --prefix=PREFIX

  * Have sudo permission, but do not want to compile as root: --with-sudo

  * Want debug message enabled: -- enable-logging=verbose

$ ./configure [ --with-sudo | --prefix=PREFIX | --enable-logging=verbose] $ make; sudo make install

After installing it, you need to create an empty configuration file: touch ~/.config/gnunet.conf

And finally you can start GNUnet with $ gnunet-arm -s

Building GLPK for MinGW
-----------------------

GNUnet now requires the GNU Linear Programming Kit (GLPK). Since there's is no package you can install with mingw-get you have to compile it from source:

  * Download the latest version from http://ftp.gnu.org/gnu/glpk/

  * Unzip it using your favourite unzipper In the MSYS shell:

  * change to the respective directory

  * ./configure '--build=i686-pc-mingw32'

  * run make install check

     MinGW does not automatically detect the correct buildtype so you have to specify it manually

GUI build instructions for Ubuntu 12.04 using Subversion
--------------------------------------------------------

After installing GNUnet you can continue installing the GNUnet GUI tools:

First, install the required dependencies:

$ sudo apt-get install libgladeui-dev libqrencode-dev

Please ensure that the GNUnet shared libraries can be found by the linker. If you installed GNUnet libraries in a non standard path (say GNUNET_PREFIX=/usr/local/lib/), you can

  * set the environmental variable permanently to LD_LIBRARY_PATH=$GNUNET_PREFIX

  * or add $GNUNET_PREFIX to /etc/ld.so.conf

Now you can checkout and compile the GNUnet GUI tools

$ svn co https://gnunet.org/svn/gnunet-gtk $ cd gnunet-gtk $ ./bootstrap $ ./configure --prefix=$GNUNET_PREFIX/.. --with-gnunet=$GNUNET_PREFIX/.. $ make install

Installation with gnunet-update
-------------------------------

gnunet-update project is an effort to introduce updates to GNUnet installations. An interesting to-be-implemented-feature of gnunet-update is that these updates are propagated through GNUnet's peer-to-peer network. More information about gnunet-update can be found at https://gnunet.org/svn/gnunet-update/README.

While the project is still under development, we have implemented the following features which we believe may be helpful for users and we would like them to be tested:

  * Packaging GNUnet installation along with its run-time dependencies into update packages

  * Installing update packages into compatible hosts

  * Updating an existing installation (which had been installed by gnunet-update) to a newer one

The above said features of gnunet-update are currently available for testing on GNU/Linux systems.

The following is a guide to help you get started with gnunet-update. It shows you how to install the testing binary packages of GNUnet 0.9.1 we have at https://gnunet.org/install/

gnunet-update needs the following:

  * python ( 2.6 or above)

  * gnupg

  * python-gpgme

Checkout gnunet-update:

$ svn checkout -r24905 https://gnunet.org/svn/gnunet-update

For security reasons, all packages released for gnunet-update from us are signed with the key at https://gnunet.org/install/key.txt You would need to import this key into your gpg key ring. gnunet-update uses this key to verify the integrity of the packages it installs

$ gpg --recv-keys 7C613D78

Download the packages relevant to your architecture (currently I have access to GNU/Linux machines on x86_64 and i686, so only two for now, hopefully more later) from https://gnunet.org/install/.

To install the downloaded package into the directory /foo:

gnunet-update/bin/gnunet-update install downloaded/package /foo

The installer reports the directories into which shared libraries and dependencies have been installed. You may need to add the reported shared library installation paths to LD_LIBRARY_PATH before you start running any installed binaries.

Please report bugs at https://gnunet.org/bugs/ under the project 'gnunet-update'.

Instructions for Microsoft Windows Platforms (Old)
--------------------------------------------------

This document is a DEPRECATED installation guide for gnunet on windows. It will not work for recent gnunet versions, but maybe it will be of some use if problems arise.

The Windows build uses a UNIX emulator for Windows, MinGW (http://www.mingw.org/), to build the executable modules. These modules run natively on Windows and do not require additional emulation software besides the usual dependencies.

GNUnet development is mostly done under Linux and especially SVN checkouts may not build out of the box. We regret any inconvenience, and if you have problems, please report them.

Hardware and OS requirements
............................

  * Pentium II or equivalent processor, 350 MHz or better

  * 128 MB RAM

  * 600 MB free disk space

  * Windows 2000 or Windows XP are recommended

Software installation
.....................

  * Compression software The software packages GNUnet depends on are usually compressed using UNIX tools like tar, gzip and bzip2. If you do not already have an utility that is able to extract such archives, get 7-Zip (http://www.7-zip.org/).

  * UNIX environment The MinGW project provides the compiler toolchain that is used to build GNUnet. Get the following packages from the MinGW project (http://sourceforge.net/projects/mingw/files/):

       * GCC core

       * GCC g++

       * MSYS

       * MSYS Developer Tool Kit (msysDTK)

       * MSYS Developer Tool Kit - msys-autoconf (bin)

       * MSYS Developer Tool Kit - msys-automake (bin)

       * MinGW Runtime

       * MinGW Utilities

       * Windows API

       * Binutils

       * make

       * pdcurses

       * GDB (snapshot)

       * Install MSYS (to c:\mingw, for example.) Do not use spaces in the pathname (c:\program files\mingw).

       * Install MinGW runtime, utilities and GCC to a subdirectory (to c:\mingw\mingw, for example)

       * Install the Development Kit to the MSYS directory (c:\mingw)

       * Create a batch file bash.bat in your MSYS directory with the files:

               bin\sh.exe --login

          This batch file opens a shell which is used to invoke the build processes.. MinGW's standard shell (msys.bat) is not suitable because it opens a separate console window On Vista, bash.bat needs to be run as administrator.

       * Start bash.sh and rename (c:\mingw\mingw\)lib\libstdc++.la to avoid problems:

               mv /usr/mingw/lib/libstdc++.la /usr/mingw/lib/libstdc++.la.broken

       * Unpack the Windows API to the MinGW directory (c:\mingw\mingw\) and remove the declaration of DATADIR from (c:\mingw\mingw\)include\objidl.h (lines 55-58)

       * Unpack autoconf, automake to the MSYS directory (c:\mingw)

       * Install all other packages to the MinGW directory (c:\mingw\mingw\)

  * GNU Libtool GNU Libtool is required to use shared libraries. Get the prebuilt package from here and unpack it to the MinGW directory (c:\mingw)

  * Pthreads GNUnet uses the portable POSIX thread library for multi-threading..

       * Save libpthreadGC2.a (ftp://sources.redhat.com/pub/pthreads-win32/dll-latest/lib/x86 /libpthreadGC2.a) (x86) or libpthreadGC2. a (ftp://sources.redhat.c om/pub/pthreads-win32/dll-latest/lib/x64/libpthreadGC2.a) (x64) as libpthread.a into the lib directory (c:\mingw\mingw\lib\libpt hread.a)

       * Save pthreadGC2.dll (ftp://sources.redhat.com/pub/pthreads-win32/dll-latest/lib/x86 /pthreadGC2.dll) (x86) or libpthreadGC2.a (ftp://sources.redhat.c om/pub/pthreads-win32/dll-latest/lib/x64/pthreadGC2.dll) (x64) into the MinGW bin directory (c:\mingw\mingw\bin)

       * Download all header files from include/ (ftp://sources.redhat.com/pub/pthread s-win32/dll-latest/include/) to the include directory (c:\mingw\mingw\include)

  * GNU MP

     GNUnet uses the GNU Multiple Precision library for special cryptographic operations. Get the GMP binary package from the MinGW repository (http://sourceforge.net/projects/mingwrep/) and unpack it to the MinGW directory (c:\mingw\mingw)

  * GNU Gettext GNU gettext is used to provide national language support. Get the prebuilt package from hereand unpack it to the MinGW directory (c:\mingw\mingw)

  * GNU iconv GNU Libiconv is used for character encoding conversion. Get the prebuilt package from here and unpack it to the MinGW directory (c:\mingw\mingw)

  * SQLite GNUnet uses the SQLite database to store data. Get the prebuilt binary from here and unpack it to your MinGW directory.

  * MySQL As an alternative to SQLite, GNUnet also supports MySQL.

       * Get the binary installer from the MySQL project (http://dev.mysql.com/downloads/mysql/4.1.html#Windows) (version 4.1), install it and follow the instructions in README.mysql.

       * Create a temporary build directory (c:\mysql)

       * Copy the directories include\ and lib\ from the MySQL directory to the new directory

       * Get the patches from Bug #8906 (http://bugs.mysql.com/bug.php?id=8906&files=1) and Bug #8872 (http://bugs.mysql.com/bug.php?id=8872&files=1) (the latter is only required for MySQL

               patch -p 0

       * Move lib\opt\libmysql.dll to lib\libmysql.dll

       * Change to lib\ and create an import library:

               dlltool --input-def ../include/libmySQL.def --dllname libmysql.dll
                 --output-lib libmysqlclient.a -k

       * Copy include\* to include\mysql\

       * Pass "--with-mysql=/c/mysql" to ./configure and copy libmysql.dll to your PATH or GNUnet's bin directory

  * GTK+ gnunet-gtk and libextractor depend on GTK. Get the the binary and developer packages of atk, glib, gtk, iconv, gettext-runtime, pango from gtk.org (ftp://ftp.gtk.org/pub/gtk/v2.6/win32) and unpack it to the MinGW directory (c:\mingw\mingw) Get pkg-config (http://www.gtk.org/download/win32.php) and libpng and unpack them to the MinGW directory (c:\mingw\mingw) Here is an all-in-one package for gtk+dependencies (http://ftp.gnome.org/pub/gnome/binaries/win32/gtk+/2.24/gtk+-bundle_2.24.10-20120208_win32.zip). Do not overwrite any existing files!

  * Glade gnunet-gtk and and gnunet-setup were created using this interface builder

       * Get the Glade and libglade (-bin and -devel) packages (without GTK!) from GladeWin32 (http://gladewin32.sourceforge.net/) and unpack it to the MinGW directory (c:\mingw\mingw)

       * Get libxml from here and unpack it to the MinGW directory (c:\mingw\mingw).

  * zLib libextractor requires zLib to decompress some file formats. GNUnet uses it to (de)compress meta-data. Get zLib from here (Signature) and unpack it to the MinGW directory (c:\mingw\mingw)

  * Bzip2 libextractor also requires Bzip2 to decompress some file formats. Get Bzip2 (binary and developer package) from GnuWin32 (http://gnuwin32.sourceforge.net/packages/bzip2.htm) and unpack it to the MinGW directory (c:\mingw\mingw)

  * Libgcrypt Libgcrypt provides the cryptographic functions used by GNUnet Get Libgcrypt from here (ftp://ftp.gnupg.org/gcrypt/libgcrypt/), compile and place it in the MinGW directory (c:\mingw\mingw). Currently you need at least version 1.4.2 to compile GNUnet.

  * PlibC PlibC emulates Unix functions under Windows. Get PlibC from here and unpack it to the MinGW directory (c:\mingw\mingw)

  * OGG Vorbis OGG Vorbis is used to extract meta-data from .ogg files Get the packages libogg (http://www.gnunet.org/libextractor/download/win/libogg-1.1.4.zip) and libvorbis (http://www.gnunet.org/libextractor/download/win/libvorbis-1.2.3.zip) from the libextractor win32 build (http://ftp.gnu.org/gnu/libextractor/libextractor-w32-1.0.0.zip) and unpack them to the MinGW directory (c:\mingw\mingw)

  * Exiv2 (lib)Exiv2 is used to extract meta-data from files with Exiv2 meta-data Download Exiv2 (http://www.gnunet.org/libextractor/download/win/exiv2-0.18.2.zip) and unpack it to the MSYS directory (c:\mingw)

Building libextractor and GNUnet
................................

Before you compile libextractor or GNUnet, be sure to set PKG_CONFIG_PATH:

     export PKG_CONFIG_PATH=/mingw/lib/pkgconfig

See Installation for basic instructions on building libextractor and GNUnet. By default, all modules that are created in this way contain debug information and are quite large. To compile release versions (small and fast) set the variable CFLAGS:

     export CFLAGS='-O2 -march=pentium -fomit-frame-pointer'
     ./configure --prefix=$HOME --with-extractor=$HOME

Installer
.........

The GNUnet installer is made with NSIS (http://nsis.sourceforge.net/). The installer script is located in contrib\win in the GNUnet source tree.

Source
......

The sources of all dependencies are available here.

Portable GNUnet
===============

Quick instructions on how to use the most recent GNUnet on most GNU/Linux distributions

Currently this has only been tested on Ubuntu 12.04, 12.10, 13.04, Debian and CentOS 6, but it should work on almost any GNU/Linux distribution. More in-detail information can be found in the handbook.

Prerequisites
-------------

Open a terminal and paste this line into it to install all required tools needed: sudo apt-get install python-gpgme subversion

Download & set up gnunet-update
-------------------------------

The following command will download a working version of gnunet-update with the subversion tool and import the public key which is needed for authentication:

     svn checkout -r24905 https://gnunet.org/svn/gnunet-update ~/gnunet-update
     cd ~/gnunet-update
     gpg --keyserver "hkp://keys.gnupg.net" --recv-keys 7C613D78

Install GNUnet
--------------

Download and install GNUnet binaries which can be found here and set library paths:

     wget -P /tmp https://gnunet.org/install/packs/gnunet-0.9.4-`uname -m`.tgz
     ./bin/gnunet-update install /tmp/gnunet-0.9*.tgz ~
     echo "PATH DEFAULT=${PATH}:$HOME/bin" >> ~/.pam_environment
     echo -e "${HOME}/lib\n${HOME}/lib/gnunet-deps" | sudo tee \
      /etc/ld.so.conf.d/gnunet.conf > /dev/null
     sudo ldconfig

You may need to re-login once after executing these last commands

That's it, GNUnet is installed in your home directory now. GNUnet can be configured and afterwards started by executing gnunet-arm -s.

The graphical configuration interface
=====================================

If you also would like to use gnunet-gtk and gnunet-setup (highly recommended for beginners), do:

     wget -P /tmp https://gnunet.org/install/packs/gnunet-0.9.4-gtk-0.9.4-`uname -m`.tgz
     sh ~/gnunet-update/bin/gnunet-update install /tmp/gnunet-*gtk*.tgz ~
     sudo ldconfig

Now you can run gnunet-setup for easy configuration of your GNUnet peer.

Configuring your peer
---------------------

This chapter will describe the various configuration options in GNUnet.

The easiest way to configure your peer is to use the gnunet-setup tool. gnunet-setup is part of the gnunet-gtk download. You might have to install it separately.

Many of the specific sections from this chapter actually are linked from within gnunet-setup to help you while using the setup tool.

While you can also configure your peer by editing the configuration file by hand, this is not recommended for anyone except for developers.

Configuring the Friend-to-Friend (F2F) mode
-------------------------------------------

GNUnet knows three basic modes of operation. In standard "peer-to-peer" mode, your peer will connect to any peer. In the pure "friend-to-friend" mode, your peer will ONLY connect to peers from a list of friends specified in the configuration. Finally, in mixed mode, GNUnet will only connect to arbitrary peers if it has at least a specified number of connections to friends.

When configuring any of the F2F modes, you first need to create a file with the peer identities of your friends. Ask your friends to run

     $ gnunet-peerinfo -sq

The output of this command needs to be added to your friends file, which is simply a plain text file with one line per friend with the output from the above command.

You then specify the location of your friends file in the "FRIENDS" option of the "topology" section.

Once you have created the friends file, you can tell GNUnet to only connect to your friends by setting the "FRIENDS-ONLY" option (again in the "topology" section) to YES.

If you want to run in mixed-mode, set "FRIENDS-ONLY" to NO and configure a minimum number of friends to have (before connecting to arbitrary peers) under the "MINIMUM-FRIENDS" option.

If you want to operate in normal P2P-only mode, simply set "MINIMUM-FRIENDS" to zero and "FRIENDS_ONLY" to NO. This is the default.

Configuring the hostlist to bootstrap
-------------------------------------

After installing the software you need to get connected to the GNUnet network. The configuration file included in your download is already configured to connect you to the GNUnet network. In this section the relevant configuration settings are explained.

To get an initial connection to the GNUnet network and to get to know peers already connected to the network you can use the so called bootstrap servers. These servers can give you a list of peers connected to the network. To use these bootstrap servers you have to configure the hostlist daemon to activate bootstrapping.

To activate bootstrapping edit your configuration file and edit the [hostlist]-section. You have to set the argument "-b" in the options line:

     [hostlist]
     OPTIONS = -b

Additionally you have to specify which server you want to use. The default bootstrapping server is "http://v10.gnunet.org/hostlist". [^] To set the server you have to edit the line "SERVERS" in the hostlist section. To use the default server you should set the lines to

     SERVERS = http://v10.gnunet.org/hostlist [^]

To use bootstrapping your configuration file should include these lines:

     [hostlist]
     OPTIONS = -b
     SERVERS = http://v10.gnunet.org/hostlist [^]

Besides using bootstrap servers you can configure your GNUnet peer to recieve hostlist advertisements. Peers offering hostlists to other peers can send advertisement messages to peers that connect to them. If you configure your peer to receive these messages, your peer can download these lists and connect to the peers included. These lists are persistent, which means that they are saved to your hard disk regularly and are loaded during startup.

To activate hostlist learning you have to add the "-e" switch to the OPTIONS line in the hostlist section:

     [hostlist]
     OPTIONS = -b -e

Furthermore you can specify in which file the lists are saved. To save the lists in the file "hostlists.file" just add the line:

     HOSTLISTFILE = hostlists.file

Best practice is to activate both bootstrapping and hostlist learning. So your configuration file should include these lines:

     [hostlist]
     OPTIONS = -b -e
     HTTPPORT = 8080
     SERVERS = http://v10.gnunet.org/hostlist [^]
     HOSTLISTFILE = $SERVICEHOME/hostlists.file

Configuration of the HOSTLIST proxy settings
--------------------------------------------

The hostlist client can be configured to use a proxy to connect to the hostlist server. This functionality can be configured in the configuration file directly or using the gnunet-setup tool.

The hostlist client supports the following proxy types at the moment:

  * HTTP and HTTP 1.0 only proxy

  * SOCKS 4/4a/5/5 with hostname

In addition authentication at the proxy with username and password can be configured.

To configure proxy support for the hostlist client in the gnunet-setup tool, select the "hostlist" tab and select the appropriate proxy type. The hostname or IP address (including port if required) has to be entered in the "Proxy hostname" textbox. If required, enter username and password in the "Proxy username" and "Proxy password" boxes. Be aware that these information will be stored in the configuration in plain text.

To configure these options directly in the configuration, you can configure the following settings in the [hostlist] section of the configuration:

      # Type of proxy server,
      # Valid values: HTTP, HTTP_1_0, SOCKS4, SOCKS5, SOCKS4A, SOCKS5_HOSTNAME
      # Default: HTTP
      # PROXY_TYPE = HTTP

     # Hostname or IP of proxy server
      # PROXY =
      # User name for proxy server
      # PROXY_USERNAME =
      # User password for proxy server
      # PROXY_PASSWORD =

Configuring your peer to provide a hostlist
-------------------------------------------

If you operate a peer permanently connected to GNUnet you can configure your peer to act as a hostlist server, providing other peers the list of peers known to him.

Yor server can act as a bootstrap server and peers needing to obtain a list of peers can contact him to download this list. To download this hostlist the peer uses HTTP. For this reason you have to build your peer with libcurl and microhttpd support. How you build your peer with this options can be found here: https://gnunet.org/generic_installation

To configure your peer to act as a bootstrap server you have to add the "-p" option to OPTIONS in the [hostlist] section of your configuration file. Besides that you have to specify a port number for the http server. In conclusion you have to add the following lines:

     [hostlist]
     HTTPPORT = 12980
     OPTIONS = -p

If your peer acts as a bootstrap server other peers should know about that. You can advertise the hostlist your are providing to other peers. Peers connecting to your peer will get a message containing an advertisement for your hostlist and the URL where it can be downloaded. If this peer is in learning mode, it will test the hostlist and, in the case it can obtain the list successfully, it will save it for bootstrapping.

To activate hostlist advertisement on your peer, you have to set the following lines in your configuration file:

     [hostlist]
     EXTERNAL_DNS_NAME = example.org
     HTTPPORT = 12981
     OPTIONS = -p -a

With this configuration your peer will a act as a bootstrap server and advertise this hostlist to other peers connecting to him. The URL used to download the list will be http://example.org:12981/.

Please notice:

  * The hostlist is not human readable, so you should not try to download it using your webbrowser. Just point your GNUnet peer to the address!

  * Advertising without providing a hostlist does not make sense and will not work.

Configuring the datastore
-------------------------

The datastore is what GNUnet uses to for long-term storage of file-sharing data. Note that long-term does not mean 'forever' since content does have an expiration date, and of course storage space is finite (and hence sometimes content may have to be discarded).

Use the "QUOTA" option to specify how many bytes of storage space you are willing to dedicate to GNUnet.

In addition to specifying the maximum space GNUnet is allowed to use for the datastore, you need to specify which database GNUnet should use to do so. Currently, you have the choice between sqLite, MySQL and Postgres.

Configuring the MySQL database
------------------------------

This section describes how to setup the MySQL database for GNUnet.

Note that the mysql plugin does NOT work with mysql before 4.1 since we need prepared statements. We are generally testing the code against MySQL 5.1 at this point.

Reasons for using MySQL
-----------------------

  * On up-to-date hardware where mysql can be used comfortably, this module will have better performance than the other database choices (according to our tests).

  * Its often possible to recover the mysql database from internal inconsistencies. Some of the other databases do not support repair.

Reasons for not using MySQL
---------------------------

  * Memory usage (likely not an issue if you have more than 1 GB)

  * Complex manual setup

Setup Instructions
------------------

  * In gnunet.conf set in section "DATASTORE" the value for "DATABASE" to "mysql".

  * Access mysql as root:

          $ mysql -u root -p

     and issue the following commands, replacing $USER with the username that will be running gnunet-arm (so typically "gnunet"):

          CREATE DATABASE gnunet;
          GRANT select,insert,update,delete,create,alter,drop,create temporary tables
                   ON gnunet.* TO $USER@localhost;
          SET PASSWORD FOR $USER@localhost=PASSWORD('$the_password_you_like');
          FLUSH PRIVILEGES;

  * In the $HOME directory of $USER, create a ".my.cnf" file with the following lines

          [client]
          user=$USER
          password=$the_password_you_like

Thats it. Note that .my.cnf file is a slight security risk unless its on a safe partition. The $HOME/.my.cnf can of course be a symbolic link. Luckily $USER has only priviledges to mess up GNUnet's tables, which should be pretty harmless.

Testing
-------

You should briefly try if the database connection works. First, login as $USER. Then use:

     $ mysql -u $USER
     mysql> use gnunet;

If you get the message "Database changed" it probably works.

If you get "ERROR 2002: Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)" it may be resolvable by "ln -s /var/run/mysqld/mysqld.sock /tmp/mysql.sock" so there may be some additional trouble depending on your mysql setup.

Performance Tuning
------------------

For GNUnet, you probably want to set the option

     innodb_flush_log_at_trx_commit = 0

for a rather dramatic boost in MySQL performance. However, this reduces the "safety" of your database as with this options you may loose transactions during a power outage. While this is totally harmless for GNUnet, the option applies to all applications using MySQL. So you should set it if (and only if) GNUnet is the only application on your system using MySQL.

Setup for running Testcases
---------------------------

If you want to run the testcases, you must create a second database "gnunetcheck" with the same username and password. This database will then be used for testing ("make check").

Configuring the Postgres database
---------------------------------

This text describes how to setup the Postgres database for GNUnet.

This Postgres plugin was developed for Postgres 8.3 but might work for earlier versions as well.

Reasons to use Postgres
-----------------------

  * Easier to setup than MySQL

  * Real database

Reasons not to use Postgres
---------------------------

  * Quite slow

  * Still some manual setup required

Manual setup instructions
-------------------------

  * In gnunet.conf set in section "DATASTORE" the value for "DATABASE" to "postgres".

  * Access Postgres to create a user:

     with Postgres 8.x, use:

               # su - postgres
               $ createuser

          and enter the name of the user running GNUnet for the role interactively. Then, when prompted, do not set it to superuser, allow the creation of databases, and do not allow the creation of new roles.

     with Postgres 9.x, use:

               # su - postgres
               $ createuser -d $GNUNET_USER

          where $GNUNET_USER is the name of the user running GNUnet.

  * As that user (so typically as user "gnunet"), create a database (or two):

          $ createdb gnunet
          # this way you can run "make check"
          $ createdb gnunetcheck

Now you should be able to start gnunet-arm.

Testing the setup manually
--------------------------

You may want to try if the database connection works. First, again login as the user who will run gnunet-arm. Then use,

     $ psql gnunet # or gnunetcheck
     gnunet=> \dt

If, after you have started gnunet-arm at least once, you get a gn090 table here, it probably works.

Configuring the datacache
-------------------------

The datacache is what GNUnet uses for storing temporary data. This data is expected to be wiped completely each time GNUnet is restarted (or the system is rebooted).

You need to specify how many bytes GNUnet is allowed to use for the datacache using the "QUOTA" option in the section "dhtcache". Furthermore, you need to specify which database backend should be used to store the data. Currently, you have the choice between sqLite, MySQL and Postgres.

Configuring the file-sharing service
------------------------------------

In order to use GNUnet for file-sharing, you first need to make sure that the file-sharing service is loaded. This is done by setting the AUTOSTART option in section "fs" to "YES". Alternatively, you can run

     $ gnunet-arm -i fs

to start the file-sharing service by hand.

Except for configuring the database and the datacache the only important option for file-sharing is content migration.

Content migration allows your peer to cache content from other peers as well as send out content stored on your system without explicit requests. This content replication has positive and negative impacts on both system performance and privacy.

FIXME: discuss the trade-offs. Here is some older text about it...

Setting this option to YES allows gnunetd to migrate data to the local machine. Setting this option to YES is highly recommended for efficiency. Its also the default. If you set this value to YES, GNUnet will store content on your machine that you cannot decrypt. While this may protect you from liability if the judge is sane, it may not (IANAL). If you put illegal content on your machine yourself, setting this option to YES will probably increase your chances to get away with it since you can plausibly deny that you inserted the content. Note that in either case, your anonymity would have to be broken first (which may be possible depending on the size of the GNUnet network and the strength of the adversary).

Configuring logging
-------------------

Logging in GNUnet 0.9.0 is controlled via the "-L" and "-l" options. Using "-L", a log level can be specified. With log level "ERROR" only serious errors are logged. The default log level is "WARNING" which causes anything of concern to be logged. Log level "INFO" can be used to log anything that might be interesting information whereas "DEBUG" can be used by developers to log debugging messages (but you need to run configure with --enable-logging=verbose to get them compiled). The "-l" option is used to specify the log file.

Since most GNUnet services are managed by gnunet-arm, using the "-l" or "-L" options directly is not possible. Instead, they can be specified using the "OPTIONS" configuration value in the respective section for the respective service. In order to enable logging globally without editing the "OPTIONS" values for each service, gnunet-arm supports a "GLOBAL_POSTFIX" option. The value specified here is given as an extra option to all services for which the configuration does contain a service-specific "OPTIONS" field.

"GLOBAL_POSTFIX" can contain the special sequence "{}" which is replaced by the name of the service that is being started. Furthermore, GLOBAL_POSTFIX is special in that sequences starting with "$" anywhere in the string are expanded (according to options in "PATHS"); this expansion otherwise is only happening for filenames and then the "$" must be the first character in the option. Both of these restrictions do not apply to "GLOBAL_POSTFIX". Note that specifying % anywhere in the "GLOBAL_POSTFIX" disables both of these features.

In summary, in order to get all services to log at level "INFO" to log-files called SERVICENAME-logs, the following global prefix should be used:

     GLOBAL_POSTFIX = -l $SERVICEHOME/{}-logs -L INFO

Configuring the transport service and plugins
---------------------------------------------

The transport service in GNUnet is responsible to maintain basic connectivity to other peers. Besides initiating and keeping connections alive it is also responsible for address validation.

The GNUnet transport supports more than one transport protocol. These protocols are configured together with the transport service.

The configuration section for the transport service itself is quite similar to all the other services

      AUTOSTART = YES
      @UNIXONLY@ PORT = 2091
      HOSTNAME = localhost
      HOME = $SERVICEHOME
      CONFIG = $DEFAULTCONFIG
      BINARY = gnunet-service-transport
      #PREFIX = valgrind
      NEIGHBOUR_LIMIT = 50
      ACCEPT_FROM = 127.0.0.1;
      ACCEPT_FROM6 = ::1;
      PLUGINS = tcp udp
      UNIXPATH = /tmp/gnunet-service-transport.sock

Different are the settings for the plugins to load PLUGINS. The first setting specifies which transport plugins to load.

  * transport-unix A plugin for local only communication with UNIX domain sockets. Used for testing and available on unix systems only. Just set the port

           [transport-unix]
           PORT = 22086
           TESTING_IGNORE_KEYS = ACCEPT_FROM;

  * transport-tcp A plugin for communication with TCP. Set port to 0 for client mode with outbound only connections

           [transport-tcp]
           # Use 0 to ONLY advertise as a peer behind NAT (no port binding)
           PORT = 2086
           ADVERTISED_PORT = 2086
           TESTING_IGNORE_KEYS = ACCEPT_FROM;
           # Maximum number of open TCP connections allowed
           MAX_CONNECTIONS = 128

  * transport-udp A plugin for communication with UDP. Supports peer discovery using broadcasts.

           [transport-udp]
           PORT = 2086
           BROADCAST = YES
           BROADCAST_INTERVAL = 30 s
           MAX_BPS = 1000000
           TESTING_IGNORE_KEYS = ACCEPT_FROM;

  * transport-http HTTP and HTTPS support is split in two part: a client plugin initiating outbound connections and a server part accepting connections from the client. The client plugin just takes the maximum number of connections as an argument.

           [transport-http_client]
           MAX_CONNECTIONS = 128
           TESTING_IGNORE_KEYS = ACCEPT_FROM;

           [transport-https_client]
           MAX_CONNECTIONS = 128
           TESTING_IGNORE_KEYS = ACCEPT_FROM;

     The server has a port configured and the maximum nunber of connections. The HTTPS part has two files with the certificate key and the certificate file.

     The server plugin supports reverse proxies, so a external hostname can be set using the EXTERNAL_HOSTNAME setting. The webserver under this address should forward the request to the peer and the configure port.

           [transport-http_server]
           EXTERNAL_HOSTNAME = fulcrum.net.in.tum.de/gnunet
           PORT = 1080
           MAX_CONNECTIONS = 128
           TESTING_IGNORE_KEYS = ACCEPT_FROM;

           [transport-https_server]
           PORT = 4433
           CRYPTO_INIT = NORMAL
           KEY_FILE = https.key
           CERT_FILE = https.cert
           MAX_CONNECTIONS = 128
           TESTING_IGNORE_KEYS = ACCEPT_FROM;

  * transport-wlan

     There is a special article how to setup the WLAN plugin, so here only the settings. Just specify the interface to use:

           [transport-wlan]
           # Name of the interface in monitor mode (typically monX)
           INTERFACE = mon0
           # Real hardware, no testing
           TESTMODE = 0
           TESTING_IGNORE_KEYS = ACCEPT_FROM;

Configuring the wlan transport plugin
-------------------------------------

The wlan transport plugin enables GNUnet to send and to receive data on a wlan interface. It has not to be connected to a wlan network as long as sender and receiver are on the same channel. This enables you to get connection to the GNUnet where no internet access is possible, for example while catastrophes or when censorship cuts you off the internet.

Requirements for the WLAN plugin
................................

  * wlan network card with monitor support and packet injection (see aircrack-ng.org (http://www.aircrack-ng.org/))

  * Linux kernel with mac80211 stack, introduced in 2.6.22, tested with 2.6.35 and 2.6.38

  * Wlantools to create the a monitor interface, tested with airmon-ng of the aircrack-ng package

Configuration
.............

There are the following options for the wlan plugin (they should be like this in your default config file, you only need to adjust them if the values are incorrect for your system)

     # section for the wlan transport plugin
     [transport-wlan]
     # interface to use, more information in the
     # "Before starting GNUnet" section of the handbook.
     INTERFACE = mon0
     # testmode for developers:
     # 0 use wlan interface,
     #1 or 2 use loopback driver for tests 1 = server, 2 = client
     TESTMODE = 0

Before starting GNUnet
......................

Before starting GNUnet, you have to make sure that your wlan interface is in monitor mode. One way to put the wlan interface into monitor mode (if your interface name is wlan0) is by executing:

      sudo airmon-ng start wlan0

Here is an example what the result should look like:

      Interface Chipset Driver
      wlan0 Intel 4965 a/b/g/n iwl4965 - [phy0]
      (monitor mode enabled on mon0)

The monitor interface is mon0 is the one that you have to put into the configuration file.

Limitations and known bugs
..........................

Wlan speed is at the maximum of 1 Mbit/s because support for choosing the wlan speed with packet injection was removed in newer kernels. Please pester the kernel developers about fixing this.

The interface channel depends on the wlan network that the card is connected to. If no connection has been made since the start of the computer, it is usually the first channel of the card. Peers will only find each other and communicate if they are on the same channel. Channels must be set manually (i.e. using iwconfig wlan0 channel 1).

Configuring HTTP(S) reverse proxy functionality using Apache or nginx
---------------------------------------------------------------------

The HTTP plugin supports data transfer using reverse proxies. A reverse proxy forwards the HTTP request he receives with a certain URL to another webserver, here a GNUnet peer.

So if you have a running Apache or nginx webserver you can configure it to be a GNUnet reverse proxy. Especially if you have a well-known webiste this improves censorship resistance since it looks as normal surfing behaviour.

To do so, you have to do two things:

  * Configure your webserver to forward the GNUnet HTTP traffic

  * Configure your GNUnet peer to announce the respective address

As an example we want to use GNUnet peer running:

  * HTTP server plugin on gnunet.foo.org:1080

  * HTTPS server plugin on gnunet.foo.org:4433

  * A apache or nginx webserver on http://www.foo.org:80/ (http://www.foo.org/)

  * A apache or nginx webserver on https://www.foo.org:443/

And we want the webserver to accept GNUnet traffic under http://www.foo.org/bar/. The required steps are described here:

Configure your Apache2 HTTP webserver

First of all you need mod_proxy installed.

Edit your webserver configuration. Edit /etc/apache2/apache2.conf or the site-specific configuration file.

In the respective server config,virtual host or directory section add the following lines:

      ProxyTimeout 300
      ProxyRequests Off
      <Location /bar/ >
      ProxyPass http://gnunet.foo.org:1080/
      ProxyPassReverse http://gnunet.foo.org:1080/
      </Location>

Configure your Apache2 HTTPS webserver

We assume that you already have an HTTPS server running, if not please check how to configure a HTTPS host. An easy to use example is the apache2/sites-available/default-ssl example configuration file.

In the respective HTTPS server config,virtual host or directory section add the following lines:

      SSLProxyEngine On
      ProxyTimeout 300
      ProxyRequests Off
      <Location /bar/ >
      ProxyPass https://gnunet.foo.org:4433/
      ProxyPassReverse https://gnunet.foo.org:4433/
      </Location>

More information about the apache mod_proxy configuration can be found at http://httpd.apache.org/docs/2.2/mod/mod_proxy.html#proxypass

Configure your nginx HTTPS webserver

Since nginx does not support chunked encoding, you first of all have to install chunkin: http://wiki.nginx.org/HttpChunkinModule

To enable chunkin add:

      chunkin on;
      error_page 411 = @my_411_error;
      location @my_411_error {
      chunkin_resume;
      }

Edit your webserver configuration. Edit /etc/nginx/nginx.conf or the site-specific configuration file.

In the server section add:

      location /bar/
      {
      proxy_pass http://gnunet.foo.org:1080/;
      proxy_buffering off;
      proxy_connect_timeout 5; # more than http_server
      proxy_read_timeout 350; # 60 default, 300s is GNUnet's idle timeout
      proxy_http_version 1.1; # 1.0 default
      proxy_next_upstream error timeout invalid_header http_500 http_503 http_502 http_504;
      }

Configure your nginx HTTPS webserver

Edit your webserver configuration. Edit /etc/nginx/nginx.conf or the site-specific configuration file.

In the server section add:

      ssl_session_timeout 6m;
      location /bar/
      {
      proxy_pass https://gnunet.foo.org:4433/;
      proxy_buffering off;
      proxy_connect_timeout 5; # more than http_server
      proxy_read_timeout 350; # 60 default, 300s is GNUnet's idle timeout
      proxy_http_version 1.1; # 1.0 default
      proxy_next_upstream error timeout invalid_header http_500 http_503 http_502 http_504;
      }

Configure your GNUnet peer

To have your GNUnet peer announce the address, you have to specify the EXTERNAL_HOSTNAME option in the [transport-http_server] section:

      [transport-http_server]
      EXTERNAL_HOSTNAME = http://www.foo.org/bar/

and/or [transport-https_server] section:

      [transport-https_server]
      EXTERNAL_HOSTNAME = https://www.foo.org/bar/

Now restart your webserver and your peer...

Blacklisting peers
------------------

Transport service supports to deny connecting to a specific peer of to a specific peer with a specific transport plugin using te blacklisting component of transport service. With blacklisting it is possible to deny connections to specific peers of to use a specific plugin to a specific peer. Peers can be blacklisted using the configuration or a blacklist client can be asked.

To blacklist peers using the configuration you have to add a section to your configuration containing the peer id of the peer to blacklist and the plugin if required.

Example:

To blacklist connections to P565... on peer AG2P... using tcp add:

      [transport-blacklist AG2PHES1BARB9IJCPAMJTFPVJ5V3A72S3F2A8SBUB8DAQ2V0O3V8G6G2JU56FHGFOHMQVKBSQFV98TCGTC3RJ1NINP82G0RC00N1520]
      P565723JO1C2HSN6J29TAQ22MN6CI8HTMUU55T0FUQG4CMDGGEQ8UCNBKUMB94GC8R9G4FB2SF9LDOBAJ6AMINBP4JHHDD6L7VD801G = tcp

To blacklist connections to P565... on peer AG2P... using all plugins add:

      [transport-blacklist-AG2PHES1BARB9IJCPAMJTFPVJ5V3A72S3F2A8SBUB8DAQ2V0O3V8G6G2JU56FHGFOHMQVKBSQFV98TCGTC3RJ1NINP82G0RC00N1520]
      P565723JO1C2HSN6J29TAQ22MN6CI8HTMUU55T0FUQG4CMDGGEQ8UCNBKUMB94GC8R9G4FB2SF9LDOBAJ6AMINBP4JHHDD6L7VD801G =

You can also add a blacklist client usign the blacklist api. On a blacklist check, blacklisting first checks internally if the peer is blacklisted and if not, it asks the blacklisting clients. Clients are asked if it is OK to connect to a peer ID, the plugin is omitted.

On blacklist check for (peer, plugin)

  * Do we have a local blacklist entry for this peer and this plugin?

  * YES: disallow connection

  * Do we have a local blacklist entry for this peer and all plugins?

  * YES: disallow connection

  * Does one of the clients disallow?

  * YES: disallow connection

Configuration of the HTTP and HTTPS transport plugins
-----------------------------------------------------

The client part of the http and https transport plugins can be configured to use a proxy to connect to the hostlist server. This functionality can be configured in the configuration file directly or using the gnunet-setup tool.

The both the HTTP and HTTPS clients support the following proxy types at the moment:

  * HTTP 1.1 proxy

  * SOCKS 4/4a/5/5 with hostname

In addition authentication at the proxy with username and password can be configured.

To configure proxy support for the clients in the gnunet-setup tool, select the "transport" tab and activate the respective plugin. Now you can select the appropriate proxy type. The hostname or IP address (including port if required) has to be entered in the "Proxy hostname" textbox. If required, enter username and password in the "Proxy username" and "Proxy password" boxes. Be aware that these information will be stored in the configuration in plain text.

To configure these options directly in the configuration, you can configure the following settings in the [transport-http_client] and [transport-https_client] section of the configuration:

     # Type of proxy server,
     # Valid values: HTTP, SOCKS4, SOCKS5, SOCKS4A, SOCKS5_HOSTNAME
     # Default: HTTP
     # PROXY_TYPE = HTTP

     # Hostname or IP of proxy server
     # PROXY =
     # User name for proxy server
     # PROXY_USERNAME =
     # User password for proxy server
     # PROXY_PASSWORD =

Configuring the GNU Name System
-------------------------------

Configuring system-wide DNS interception
........................................

Before you install GNUnet, make sure you have a user and group 'gnunet' as well as an empty group 'gnunetdns'.

When using GNUnet with system-wide DNS interception, it is absolutely necessary for all GNUnet service processes to be started by gnunet-service-arm as user and group 'gnunet'. You also need to be sure to run make install as root (or use the sudo option to configure) to grant GNUnet sufficient privileges.

With this setup, all that is required for enabling system-wide DNS interception is for some GNUnet component (VPN or GNS) to request it. The gnunet-service-dns will then start helper programs that will make the necessary changes to your firewall (iptables) rules.

Note that this will NOT work if your system sends out DNS traffic to a link-local IPv6 address, as in this case GNUnet can intercept the traffic, but not inject the responses from the link-local IPv6 address. Hence you cannot use system-wide DNS interception in conjunction with link-local IPv6-based DNS servers. If such a DNS server is used, it will bypass GNUnet's DNS traffic interception.

Using the GNU Name System (GNS) requires two different configuration steps. First of all, GNS needs to be integrated with the operating system. Most of this section is about the operating system level integration.

Additionally, each individual user who wants to use the system must also initialize his GNS zones. This can be done by running (after starting GNUnet)

     $ gnunet-gns-import.sh

after the local GNUnet peer has been started. Note that the namestore (in particular the namestore database backend) should not be reconfigured afterwards (as records are not automatically migrated between backends).

The remainder of this chapter will detail the various methods for configuring the use of GNS with your operating system.

At this point in time you have different options depending on your OS:

Use the gnunet-gns-proxy This approach works for all operating
     systems and is likely the easiest. However, it enables GNS only for browsers, not for other applications that might be using DNS, such as SSH. Still, using the proxy is required for using HTTP with GNS and is thus recommended for all users. To do this, you simply have to run the gnunet-gns-proxy-setup-ca script as the user who will run the browser (this will create a GNS certificate authority (CA) on your system and import its key into your browser), then start gnunet-gns-proxy and inform your browser to use the Socks5 proxy which gnunet-gns-proxy makes available by default on port 7777.

Use a nsswitch plugin (recommended on GNU systems)
     This approach has the advantage of offering fully personalized resolution even on multi-user systems. A potential disadvantage is that some applications might be able to bypass GNS.

Use a W32 resolver plugin (recommended on W32)
     This is currently the only option on W32 systems.

Use system-wide DNS packet interception
     This approach is recommended for the GNUnet VPN. It can be used to handle GNS at the same time; however, if you only use this method, you will only get one root zone per machine (not so great for multi-user systems).

You can combine system-wide DNS packet interception with the nsswitch plugin. The setup of the system-wide DNS interception is described here. All of the other GNS-specific configuration steps are described in the following sections.

Configuring the GNS nsswitch plugin
...................................

The Name Service Switch (NSS) is a facility in Unix-like operating systems that provides a variety of sources for common configuration databases and name resolution mechanisms. A system administrator usually configures the operating system's name services using the file /etc/nsswitch.conf.

GNS provides a NSS plugin to integrate GNS name resolution with the operating system's name resolution process. To use the GNS NSS plugin you have to either

  * install GNUnet as root or

  * compile GNUnet with the --with-sudo=yes switch.

Name resolution is controlled by the hosts section in the NSS configuration. By default this section first performs a lookup in the /etc/hosts file and then in DNS. The nsswitch file should contain a line similar to:

     hosts: files dns [NOTFOUND=return] mdns4_minimal mdns4

Here the GNS NSS plugin can be added to perform a GNS lookup before performing a DNS lookup. The GNS NSS plugin has to be added to the "hosts" section in /etc/nsswitch.conf file before DNS related plugins:

     ...
     hosts: files gns [NOTFOUND=return] dns mdns4_minimal mdns4
     ...

The NOTFOUND=return will ensure that if a .gnu name is not found in GNS it will not be queried in DNS.

Configuring GNS on W32
......................

This document is a guide to configuring GNU Name System on W32-compatible platforms.

After GNUnet is installed, run the w32nsp-install tool:

     w32nsp-install.exe libw32nsp-0.dll

('0' is the library version of W32 NSP; it might increase in the future, change the invocation accordingly).

This will install GNS namespace provider into the system and allow other applications to resolve names that end in 'gnu' and 'zkey'. Note that namespace provider requires gnunet-gns-helper-service-w32 to be running, as well as gns service itself (and its usual dependencies).

Namespace provider is hardcoded to connect to 127.0.0.1:5353, and this is where gnunet-gns-helper-service-w32 should be listening to (and is configured to listen to by default).

To uninstall the provider, run:

     w32nsp-uninstall.exe

(uses provider GUID to uninstall it, does not need a dll name).

Note that while MSDN claims that other applications will only be able to use the new namespace provider after re-starting, in reality they might stat to use it without that. Conversely, they might stop using the provider after it's been uninstalled, even if they were not re-started. W32 will not permit namespace provider library to be deleted or overwritten while the provider is installed, and while there is at least one process still using it (even after it was uninstalled).

GNS Proxy Setup
...............

When using the GNU Name System (GNS) to browse the WWW, there are several issues that can be solved by adding the GNS Proxy to your setup:

  * If the target website does not support GNS, it might assume that it is operating under some name in the legacy DNS system (such as example.com). It may then attempt to set cookies for that domain, and the web server might expect a Host: example.com header in the request from your browser. However, your browser might be using example.gnu for the Host header and might only accept (and send) cookies for example.gnu. The GNS Proxy will perform the necessary translations of the hostnames for cookies and HTTP headers (using the LEHO record for the target domain as the desired substitute).

  * If using HTTPS, the target site might include an SSL certificate which is either only valid for the LEHO domain or might match a TLSA record in GNS. However, your browser would expect a valid certificate for example.gnu, not for some legacy domain name. The proxy will validate the certificate (either against LEHO or TLSA) and then on-the-fly produce a valid certificate for the exchange, signed by your own CA. Assuming you installed the CA of your proxy in your browser's certificate authority list, your browser will then trust the HTTPS/SSL/TLS connection, as the hostname mismatch is hidden by the proxy.

  * Finally, the proxy will in the future indicate to the server that it speaks GNS, which will enable server operators to deliver GNS-enabled web sites to your browser (and continue to deliver legacy links to legacy browsers)

Setup of the GNS CA
...................

First you need to create a CA certificate that the proxy can use. To do so use the provided script gnunet-gns-proxy-ca:

     $ gnunet-gns-proxy-setup-ca

This will create a personal certification authority for you and add this authority to the firefox and chrome database. The proxy will use the this CA certificate to generate *.gnu client certificates on the fly.

Note that the proxy uses libcurl. Make sure your version of libcurl uses GnuTLS and NOT OpenSSL. The proxy will not work with libcurl compiled against OpenSSL.

Testing the GNS setup
.....................

Now for testing purposes we can create some records in our zone to test the SSL functionality of the proxy:

     $ gnunet-namestore -a -e "1 d" -n "homepage" -t A -V 131.159.74.67
     $ gnunet-namestore -a -e "1 d" -n "homepage" -t LEHO -V "gnunet.org"

At this point we can start the proxy. Simply execute

     $ gnunet-gns-proxy

Configure your browser to use this SOCKSv5 proxy on port 7777 and visit this link. If you use firefox you also have to go to about:config and set the key network.proxy.socks_remote_dns to true.

When you visit https://homepage.gnu/, you should get to the https://gnunet.org/ frontpage and the browser (with the correctly configured proxy) should give you a valid SSL certificate for homepage.gnu and no warnings. It should look like this:

Automatic Shortening in the GNU Name System
...........................................

This page describes a possible option for 'automatic name shortening', which you can choose to enable with the GNU Name System.

When GNS encounters a name for the first time, it can use the 'NICK' record of the originating zone to automatically generate a name for the zone. If automatic shortening is enabled, those auto-generated names will be placed (as private records) into your personal 'shorten' zone (to prevent confusion with manually selected names). Then, in the future, if the same name is encountered again, GNS will display the shortened name instead (the first time, the long name will still be used as shortening typically happens asynchronously as looking up the 'NICK' record takes some time). Using this feature can be a convenient way to avoid very long .gnu names; however, note that names from the shorten-zone are assigned on a first-come-first-serve basis and should not be trusted. Furthermore, if you enable this feature, you will no longer see the full delegation chain for zones once shortening has been applied.

Configuring the GNUnet VPN
--------------------------

Before configuring the GNUnet VPN, please make sure that system-wide DNS interception is configured properly as described in the section on the GNUnet DNS setup.

The default-options for the GNUnet VPN are usually sufficient to use GNUnet as a Layer 2 for your Internet connection. However, what you always have to specify is which IP protocol you want to tunnel: IPv4, IPv6 or both. Furthermore, if you tunnel both, you most likely should also tunnel all of your DNS requests. You theoretically can tunnel "only" your DNS traffic, but that usually makes little sense.

The other options as shown on the gnunet-setup tool are:

IPv4 address for interface
..........................

This is the IPv4 address the VPN interface will get. You should pick an 'private' IPv4 network that is not yet in use for you system. For example, if you use 10.0.0.1/255.255.0.0 already, you might use 10.1.0.1/255.255.0.0. If you use 10.0.0.1/255.0.0.0 already, then you might use 192.168.0.1/255.255.0.0. If your system is not in a private IP-network, using any of the above will work fine. You should try to make the mask of the address big enough (255.255.0.0 or, even better, 255.0.0.0) to allow more mappings of remote IP Addresses into this range. However, even a 255.255.255.0-mask will suffice for most users.

IPv6 address for interface
..........................

The IPv6 address the VPN interface will get. Here you can specify any non-link-local address (the address should not begin with "fe80:"). A subnet Unique Local Unicast (fd00::/8-prefix) that you are currently not using would be a good choice.

Configuring the GNUnet VPN DNS
..............................

To resolve names for remote nodes, activate the DNS exit option.

Configuring the GNUnet VPN Exit Service
.......................................

If you want to allow other users to share your Internet connection (yes, this may be dangerous, just as running a Tor exit node) or want to provide access to services on your host (this should be less dangerous, as long as those services are secure), you have to enable the GNUnet exit daemon.

You then get to specify which exit functions you want to provide. By enabling the exit daemon, you will always automatically provide exit functions for manually configured local services (this component of the system is under development and not documented further at this time). As for those services you explicitly specify the target IP address and port, there is no significant security risk in doing so.

Furthermore, you can serve as a DNS, IPv4 or IPv6 exit to the Internet. Being a DNS exit is usually pretty harmless. However, enabling IPv4 or IPv6-exit without further precautions may enable adversaries to access your local network, send spam, attack other systems from your Internet connection and to other mischief that will appear to come from your machine. This may or may not get you into legal trouble. If you want to allow IPv4 or IPv6-exit functionality, you should strongly consider adding additional firewall rules manually to protect your local network and to restrict outgoing TCP traffic (i.e. by not allowing access to port 25). While we plan to improve exit-filtering in the future, you're currently on your own here. Essentially, be prepared for any kind of IP-traffic to exit the respective TUN interface (and GNUnet will enable IP-forwarding and NAT for the interface automatically).

Additional configuration options of the exit as shown by the gnunet-setup tool are:

IP Address of external DNS resolver
...................................

If DNS traffic is to exit your machine, it will be send to this DNS resolver. You can specify an IPv4 or IPv6 address.

IPv4 address for Exit interface
...............................

This is the IPv4 address the Interface will get. Make the mask of the address big enough (255.255.0.0 or, even better, 255.0.0.0) to allow more mappings of IP addresses into this range. As for the VPN interface, any unused, private IPv4 address range will do.

IPv6 address for Exit interface
...............................

The public IPv6 address the interface will get. If your kernel is not a very recent kernel and you are willing to manually enable IPv6-NAT, the IPv6 address you specify here must be a globally routed IPv6 address of your host.

Suppose your host has the address 2001:4ca0::1234/64, then using 2001:4ca0::1:0/112 would be fine (keep the first 64 bits, then change at least one bit in the range before the bitmask, in the example above we changed bit 111 from 0 to 1).

You may also have to configure your router to route traffic for the entire subnet (2001:4ca0::1:0/112 for example) through your computer (this should be automatic with IPv6, but obviously anything can be disabled).

Bandwidth Configuration
-----------------------

You can specify how many bandwidth GNUnet is allowed to use to receive and send data. This is important for users with limited bandwidth or traffic volume.

Configuring NAT
---------------

Most hosts today do not have a normal global IP address but instead are behind a router performing Network Address Translation (NAT) which assigns each host in the local network a private IP address. As a result, these machines cannot trivially receive inbound connections from the Internet. GNUnet supports NAT traversal to enable these machines to receive incoming connections from other peers despite their limitations.

In an ideal world, you can press the "Attempt automatic configuration" button in gnunet-setup to automatically configure your peer correctly. Alternatively, your distribution might have already triggered this automatic configuration during the installation process. However, automatic configuration can fail to determine the optimal settings, resulting in your peer either not receiving as many connections as possible, or in the worst case it not connecting to the network at all.

To manually configure the peer, you need to know a few things about your network setup. First, determine if you are behind a NAT in the first place. This is always the case if your IP address starts with "10.*" or "192.168.*". Next, if you have control over your NAT router, you may choose to manually configure it to allow GNUnet traffic to your host. If you have configured your NAT to forward traffic on ports 2086 (and possibly 1080) to your host, you can check the "NAT ports have been opened manually" option, which corresponds to the "PUNCHED_NAT" option in the configuration file. If you did not punch your NAT box, it may still be configured to support UPnP, which allows GNUnet to automatically configure it. In that case, you need to install the "upnpc" command, enable UPnP (or PMP) on your NAT box and set the "Enable NAT traversal via UPnP or PMP" option (corresponding to "ENABLE_UPNP" in the configuration file).

Some NAT boxes can be traversed using the autonomous NAT traversal method. This requires certain GNUnet components to be installed with "SUID" prividledges on your system (so if you're installing on a system you do not have administrative rights to, this will not work). If you installed as 'root', you can enable autonomous NAT traversal by checking the "Enable NAT traversal using ICMP method". The ICMP method requires a way to determine your NAT's external (global) IP address. This can be done using either UPnP, DynDNS, or by manual configuration. If you have a DynDNS name or know your external IP address, you should enter that name under "External (public) IPv4 address" (which corresponds to the "EXTERNAL_ADDRESS" option in the configuration file). If you leave the option empty, GNUnet will try to determine your external IP address automatically (which may fail, in which case autonomous NAT traversal will then not work).

Finally, if you yourself are not behind NAT but want to be able to connect to NATed peers using autonomous NAT traversal, you need to check the "Enable connecting to NATed peers using ICMP method" box.

Peer configuration for distributions
------------------------------------

The "GNUNET_DATA_HOME" in "[path]" in /etc/gnunet.conf should be manually set to "/var/lib/gnunet/data/" as the default "~/.local/share/gnunet/" is probably not that appropriate in this case. Similarly, distributions may consider pointing "GNUNET_RUNTIME_DIR" to "/var/run/gnunet/" and "GNUNET_HOME" to "/var/lib/gnunet/". Also, should a distribution decide to override system defaults, all of these changes should be done in a custom /etc/gnunet.conf and not in the files in the config.d/ directory.

Given the proposed access permissions, the "gnunet-setup" tool must be run as use "gnunet" (and with option "-c /etc/gnunet.conf" so that it modifies the system configuration). As always, gnunet-setup should be run after the GNUnet peer was stopped using "gnunet-arm -e". Distributions might want to include a wrapper for gnunet-setup that allows the desktop-user to "sudo" (i.e. using gtksudo) to the "gnunet" user account and then runs "gnunet-arm -e", "gnunet-setup" and "gnunet-arm -s" in sequence.

How to start and stop a GNUnet peer
===================================

This section describes how to start a GNUnet peer. It assumes that you have already compiled and installed GNUnet and its' dependencies. Before you start a GNUnet peer, you may want to create a configuration file using gnunet-setup (but you do not have to). Sane defaults should exist in your $GNUNET_PREFIX/share/gnunet/config.d/ directory, so in practice you could simply start without any configuration. If you want to configure your peer later, you need to stop it before invoking the gnunet-setup tool to customize further and to test your configuration (gnunet-setup has build-in test functions).

The most important option you might have to still set by hand is in [PATHS]. Here, you use the option "GNUNET_HOME" to specify the path where GNUnet should store its data. It defaults to $HOME/, which again should work for most users. Make sure that the directory specified as GNUNET_HOME is writable to the user that you will use to run GNUnet (note that you can run frontends using other users, GNUNET_HOME must only be accessible to the user used to run the background processes).

You will also need to make one central decision: should all of GNUnet be run under your normal UID, or do you want distinguish between system-wide (user-independent) GNUnet services and personal GNUnet services. The multi-user setup is slightly more complicated, but also more secure and generally recommended.

The Single-User Setup
---------------------

For the single-user setup, you do not need to do anything special and can just start the GNUnet background processes using gnunet-arm. By default, GNUnet looks in ~/.config/gnunet.conf for a configuration (or $XDG_CONFIG_HOME/gnunet.conf if $XDG_CONFIG_HOME is defined). If your configuration lives elsewhere, you need to pass the -c FILENAME option to all GNUnet commands.

Assuming the configuration file is called ~/.config/gnunet.conf, you start your peer using the gnunet-arm command (say as user gnunet) using:

     gnunet-arm -c ~/.config/gnunet.conf -s

The "-s" option here is for "start". The command should return almost instantly. If you want to stop GNUnet, you can use:

     gnunet-arm -c ~/.config/gnunet.conf -e

The "-e" option here is for "end".

Note that this will only start the basic peer, no actual applications will be available. If you want to start the file-sharing service, use (after starting GNUnet):

     gnunet-arm -c ~/.config/gnunet.conf -i fs

The "-i fs" option here is for "initialize" the "fs" (file-sharing) application. You can also selectively kill only file-sharing support using

     gnunet-arm -c ~/.config/gnunet.conf -k fs

Assuming that you want certain services (like file-sharing) to be always automatically started whenever you start GNUnet, you can activate them by setting "FORCESTART=YES" in the respective section of the configuration file (for example, "[fs]"). Then GNUnet with file-sharing support would be started whenever you enter:

     gnunet-arm -c ~/.config/gnunet.conf -s

Alternatively, you can combine the two options:

     gnunet-arm -c ~/.config/gnunet.conf -s -i fs

Using gnunet-arm is also the preferred method for initializing GNUnet from init.

Finally, you should edit your crontab (using the crontab command) and insert a line

@reboot gnunet-arm -c ~/.config/gnunet.conf -s

to automatically start your peer whenever your system boots.

The Multi-User Setup
--------------------

This requires you to create a user gnunet and an additional group gnunetdns, prior to running make install during installation. Then, you create a configuration file /etc/gnunet.conf which should contain the lines:

     [arm]
     SYSTEM_ONLY = YES
     USER_ONLY = NO

Then, perform the same steps to run GNUnet as in the per-user configuration, except as user gnunet (including the crontab installation). You may also want to run gnunet-setup to configure your peer (databases, etc.). Make sure to pass -c /etc/gnunet.conf to all commands. If you run gnunet-setup as user gnunet, you might need to change permissions on /etc/gnunet.conf so that the gnunet user can write to the file (during setup).

Afterwards, you need to perform another setup step for each normal user account from which you want to access GNUnet. First, grant the normal user ($USER) permission to the group gnunet:

     # adduser $USER gnunet

Then, create a configuration file in ~/.config/gnunet.conf for the $USER with the lines:

     [arm]
     SYSTEM_ONLY = NO
     USER_ONLY = YES

This will ensure that gnunet-arm when started by the normal user will only run services that are per-user, and otherwise rely on the system-wide services. Note that the normal user may run gnunet-setup, but the configuration would be ineffective as the system-wide services will use /etc/gnunet.conf and ignore options set by individual users.

Again, each user should then start the peer using gnunet-arm -s --- and strongly consider adding logic to start the peer automatically to their crontab.

Afterwards, you should see two (or more, if you have more than one USER) gnunet-service-arm processes running in your system.

Killing GNUnet services
-----------------------

It is not necessary to stop GNUnet services explicitly when shutting down your computer.

It should be noted that manually killing "most" of the gnunet-service processes is generally not a successful method for stopping a peer (since gnunet-service-arm will instantly restart them). The best way to explicitly stop a peer is using gnunet-arm -e; note that the per-user services may need to be terminated before the system-wide services will terminate normally.

Access Control for GNUnet
-------------------------

This chapter documents how we plan to make access control work within the GNUnet system for a typical peer. It should be read as a best-practice installation guide for advanced users and builders of binary distributions. The recommendations in this guide apply to POSIX-systems with full support for UNIX domain sockets only.

Note that this is an advanced topic. The discussion presumes a very good understanding of users, groups and file permissions. Normal users on hosts with just a single user can just install GNUnet under their own account (and possibly allow the installer to use SUDO to grant additional permissions for special GNUnet tools that need additional rights). The discussion below largely applies to installations where multiple users share a system and to installations where the best possible security is paramount.

A typical GNUnet system consists of components that fall into four categories:

User interfaces
     User interfaces are not security sensitive and are supposed to be run and used by normal system users. The GTK GUIs and most command-line programs fall into this category. Some command-line tools (like gnunet-transport) should be excluded as they offer low-level access that normal users should not need.

System services and support tools
     System services should always run and offer services that can then be accessed by the normal users. System services do not require special permissions, but as they are not specific to a particular user, they probably should not run as a particular user. Also, there should typically only be one GNUnet peer per host. System services include the gnunet-service and gnunet-daemon programs; support tools include command-line programs such as gnunet-arm.

Priviledged helpers
     Some GNUnet components require root rights to open raw sockets or perform other special operations. These gnunet-helper binaries are typically installed SUID and run from services or daemons.

Critical services
     Some GNUnet services (such as the DNS service) can manipulate the service in deep and possibly highly security sensitive ways. For example, the DNS service can be used to intercept and alter any DNS query originating from the local machine. Access to the APIs of these critical services and their priviledged helpers must be tightly controlled.

Recommendation - Disable access to services via TCP
...................................................

GNUnet services allow two types of access: via TCP socket or via UNIX domain socket. If the service is available via TCP, access control can only be implemented by restricting connections to a particular range of IP addresses. This is acceptable for non-critical services that are supposed to be available to all users on the local system or local network. However, as TCP is generally less efficient and it is rarely the case that a single GNUnet peer is supposed to serve an entire local network, the default configuration should disable TCP access to all GNUnet services on systems with support for UNIX domain sockets. As of GNUnet 0.9.2, configuration files with TCP access disabled should be generated by default. Users can re-enable TCP access to particular services simply by specifying a non-zero port number in the section of the respective service.

Recommendation - Run most services as system user "gnunet"
..........................................................

GNUnet's main services should be run as a separate user "gnunet" in a special group "gnunet". The user "gnunet" should start the peer using "gnunet-arm -s" during system startup. The home directory for this user should be /var/lib/gnunet and the configuration file should be /etc/gnunet.conf. Only the gnunet user should have the right to access /var/lib/gnunet (mode: 700).

Recommendation - Control access to services using group "gnunet"
................................................................

Users that should be allowed to use the GNUnet peer should be added to the group "gnunet". Using GNUnet's access control mechanism for UNIX domain sockets, those services that are considered useful to ordinary users should be made available by setting "UNIX_MATCH_GID=YES" for those services. Again, as shipped, GNUnet provides reasonable defaults. Permissions to access the transport and core subsystems might additionally be granted without necessarily causing security concerns. Some services, such as DNS, must NOT be made accessible to the "gnunet" group (and should thus only be accessible to the "gnunet" user and services running with this UID).

Recommendation - Limit access to certain SUID binaries by group "gnunet"
........................................................................

Most of GNUnet's SUID binaries should be safe even if executed by normal users. However, it is possible to reduce the risk a little bit more by making these binaries owned by the group "gnunet" and restricting their execution to user of the group "gnunet" as well (4750).

Recommendation - Limit access to critical gnunet-helper-dns to group "gnunetdns"
................................................................................

A special group "gnunetdns" should be created for controlling access to the "gnunet-helper-dns". The binary should then be owned by root and be in group "gnunetdns" and be installed SUID and only be group-executable (2750). Note that the group "gnunetdns" should have no users in it at all, ever. The "gnunet-service-dns" program should be executed by user "gnunet" (via gnunet-service-arm) with the binary owned by the user "root" and the group "gnunetdns" and be SGID (2700). This way, only "gnunet-service-dns" can change its group to "gnunetdns" and execute the helper, and the helper can then run as root (as per SUID). Access to the API offered by "gnunet-service-dns" is in turn restricted to the user "gnunet" (not the group!), which means that only "benign" services can manipulate DNS queries using "gnunet-service-dns".

Differences between "make install" and these recommendations
............................................................

The current build system does not set all permissions automatically based on the recommendations above. In particular, it does not use the group "gnunet" at all (so setting gnunet-helpers other than the gnunet-helper-dns to be owned by group "gnunet" must be done manually). Furthermore, 'make install' will silently fail to set the DNS binaries to be owned by group "gnunetdns" unless that group already exists (!). An alternative name for the "gnunetdns" group can be specified using the "--with-gnunetdns=GRPNAME" configure option.