GUARANTEE THAT THERE WILL BE PROTOCOL COMPATIBILITY BETWEEN DIFFERENT
VERSIONS.
+PROTOCOL COMPATIBILITY WAS BROKEN BETWEEN secnet-0.06, secnet-0.07 AND
+secnet-0.08 FOR ENDIANNESS FIXES.
+
+THERE WILL BE ANOTHER CHANGE IN PROTOCOL IN THE secnet-0.1.x SERIES
+
* Preparation
** System software support
Ensure that you have libgmp2-dev and adns installed (and bison and
flex, and for that matter gcc...).
+[On BSD install /usr/ports/devel/bison and /usr/ports/devel/libgnugetopt]
+
If you intend to configure secnet to obtain packets from the kernel
through userv-ipif, install and configure userv-ipif. It is part of
userv-utils, available from ftp.chiark.greenend.org.uk in
config file) which has only one device file (usually /dev/net/tun) and
the other (called 'tun-old') which has many device files (/dev/tun*).
Linux-2.4 has new-style TUN, Linux-2.2, BSD and Solaris have old-style
-TUN. Currently only new-style TUN has been tested with secnet.
+TUN.
** System and network configuration
Debian):
# adduser --system --no-create-home secnet
+If you're using the 'soft routes' feature (for some classes of mobile
+device) you'll have to run as root all the time, to enable secnet to
+add and remove routes from your kernel's routing table. (This
+restriction may be relaxed later if someone writes a userv service to
+modify the routing table.)
+
+If you are joining an existing VPN, read that VPN's documentation now.
+It may supersede the next paragraph.
+
You will need to allocate two IP addresses for use by secnet. One
will be for the tunnel interface on your tunnel endpoint machine (i.e.
the address you see in 'ifconfig' when you look at the tunnel
interface). The other will be for secnet itself. These addresses
-could possibly be allocated from the range used by your internal
-network: if you do this, you should think about providing appropriate
-proxy-ARP on the machine running secnet for the two addresses.
-Alternatively the addresses could be from some other range - this
-works well if the machine running secnet is the default route out of
-your network.
+should probably be allocated from the range used by your internal
+network: if you do this, you should provide appropriate proxy-ARP on
+the internal network interface of the machine running secnet (eg. add
+an entry net/ipv4/conf/eth_whatever/proxy_arp = 1 to /etc/sysctl.conf
+on Debian systems and run sysctl -p). Alternatively the addresses
+could be from some other range - this works well if the machine
+running secnet is the default route out of your network - but this
+requires more thought.
http://www.ucam.org/cam-grin/ may be useful.
-Advanced users: secnet's IP address does not _have_ to be in the range
-of networks claimed by your end of the tunnel; it could be in the
-range of networks claimed by the other end. Doing this is confusing,
-but works.
-
* Installation
+If you installed the Debian package of secnet, skip to "If installing
+for the first time", below, and note that example.conf can be found in
+/usr/share/doc/secnet/examples.
+
To install secnet do
$ ./configure
$ make
# make install
# mkdir /etc/secnet
+
+(Note: you may see the following warning while compiling
+conffile.tab.c; I believe this is a bison bug:
+/usr/share/bison/bison.simple: In function `yyparse':
+/usr/share/bison/bison.simple:285: warning: `yyval' might be used
+ uninitialized in this function
+)
+
+Any other warnings or errors should be reported to
+steve@greenend.org.uk.
+
+If installing for the first time, do
+
# cp example.conf /etc/secnet/secnet.conf
# cd /etc/secnet
# ssh-keygen -f key -N ""
-(When upgrading, just install the new /usr/local/sbin/secnet; keep
-your current configuration file.)
+[On BSD use
+$ LDFLAGS="-L/usr/local/lib" ./configure
+$ gmake CFLAGS="-I/usr/local/include" LDFLAGS="-L/usr/local/lib"
+XXX this should eventually be worked out automatically by 'configure'.]
Generate a site file fragment for your site (see below), and submit it
-for inclusion in the vpn-sites file. Download the vpn-sites file to
-/etc/secnet/sites - MAKE SURE YOU GET AN AUTHENTIC COPY because the
-sites file contains public keys for all the sites in the VPN.
+for inclusion in your VPN's 'sites' file. Download the vpn-sites file
+to /etc/secnet/sites - MAKE SURE YOU GET AN AUTHENTIC COPY because the
+sites file contains public keys for all the sites in the VPN. Use the
+make-secnet-sites.py program provided with the secnet distribution to
+convert the distributed sites file into one that can be included in a
+secnet configuration file:
+
+# make-secnet-sites.py sites sites.conf
* Configuration
You need the following information:
-1. a short name for your site, eg. "greenend". This is used to
-identify your site in the vpn-sites file.
+1. the name of your VPN.
+
+2. the name of your location(s).
-2. the name your site will use in the key setup protocol,
-eg. "greenend" (these two will usually be similar or the same).
+3. a short name for your site, eg. "sinister". This is used to
+identify your site in the vpn-sites file, and should probably be the
+same as its hostname.
-3. the DNS name of the machine that will be the "front-end" for your
+4. the DNS name of the machine that will be the "front-end" for your
secnet installation. This will typically be the name of the gateway
-machine for your network, eg. sinister.dynamic.greenend.org.uk
+machine for your network, eg. sinister.dynamic.greenend.org.uk
secnet does not actually have to run on this machine, as long as the
machine can be configured to forward UDP packets to the machine that
is running secnet.
-4. the port number used to contact secnet at your site. This is the
+5. the port number used to contact secnet at your site. This is the
port number on the front-end machine, and does not necessarily have to
-match the port number on the machine running secnet.
+match the port number on the machine running secnet. If you want to
+use a privileged port number we suggest 410. An appropriate
+unprivileged port number is 51396. (These numbers were picked at
+random.)
-5. the list of networks accessible at your site over the VPN.
+6. the list of networks accessible at your site over the VPN.
-6. the public part of the RSA key you generated during installation
+7. the public part of the RSA key you generated during installation
(in /etc/secnet/key.pub if you followed the installation
instructions). This file contains three numbers and a comment on one
-line. The first number is the key length in bits, and can be ignored.
-The second number (typically small) is the encryption key 'e', and the
-third number (large) is the modulus 'n'.
+line.
If you are running secnet on a particularly slow machine, you may like
to specify a larger value for the key setup retry timeout than the
The site file fragment should look something like this:
-shortname {
- name "sitename";
- address "your.public.address.org.uk";
- port 5678;
- networks "172.18.45.0/24";
- key rsa-public("35","153279875126380522437827076871354104097683702803616313419670959273217685015951590424876274370401136371563604396779864283483623325238228723798087715987495590765759771552692972297669972616769731553560605291312242789575053620182470998166393580503400960149506261455420521811814445675652857085993458063584337404329");
- };
-
-See 'example-sites-file' for more examples.
+vpn sgo
+location greenend
+contact steve@greenend.org.uk
+site sinister
+ networks 192.168.73.0/24 192.168.1.0/24 172.19.71.0/24
+ address sinister.dynamic.greenend.org.uk 51396
+ pubkey 1024 35 142982503......[lots more].....0611 steve@sinister
~ian / secnet.git / blobdiff