--- gvpe/doc/gvpe.5 2005/03/18 01:53:05 1.7
+++ gvpe/doc/gvpe.5 2013/07/13 04:10:29 1.12
@@ -1,15 +1,7 @@
-.\" Automatically generated by Pod::Man v1.37, Pod::Parser v1.14
+.\" Automatically generated by Pod::Man 2.25 (Pod::Simple 3.20)
.\"
.\" Standard preamble:
.\" ========================================================================
-.de Sh \" Subsection heading
-.br
-.if t .Sp
-.ne 5
-.PP
-\fB\\$1\fR
-.PP
-..
.de Sp \" Vertical space (when we can't use .PP)
.if t .sp .5v
.if n .sp
@@ -25,11 +17,11 @@
..
.\" Set up some character translations and predefined strings. \*(-- will
.\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
-.\" double quote, and \*(R" will give a right double quote. | will give a
-.\" real vertical bar. \*(C+ will give a nicer C++. Capital omega is used to
-.\" do unbreakable dashes and therefore won't be available. \*(C` and \*(C'
-.\" expand to `' in nroff, nothing in troff, for use with C<>.
-.tr \(*W-|\(bv\*(Tr
+.\" double quote, and \*(R" will give a right double quote. \*(C+ will
+.\" give a nicer C++. Capital omega is used to do unbreakable dashes and
+.\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff,
+.\" nothing in troff, for use with C<>.
+.tr \(*W-
.ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
.ie n \{\
. ds -- \(*W-
@@ -48,22 +40,25 @@
. ds R" ''
'br\}
.\"
+.\" Escape single quotes in literal strings from groff's Unicode transform.
+.ie \n(.g .ds Aq \(aq
+.el .ds Aq '
+.\"
.\" If the F register is turned on, we'll generate index entries on stderr for
-.\" titles (.TH), headers (.SH), subsections (.Sh), items (.Ip), and index
+.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
.\" entries marked with X<> in POD. Of course, you'll have to process the
.\" output yourself in some meaningful fashion.
-.if \nF \{\
+.ie \nF \{\
. de IX
. tm Index:\\$1\t\\n%\t"\\$2"
..
. nr % 0
. rr F
.\}
-.\"
-.\" For nroff, turn off justification. Always turn off hyphenation; it makes
-.\" way too many mistakes in technical documents.
-.hy 0
-.if n .na
+.el \{\
+. de IX
+..
+.\}
.\"
.\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
.\" Fear. Run. Save yourself. No user-serviceable parts.
@@ -129,7 +124,11 @@
.\" ========================================================================
.\"
.IX Title "GVPE 5"
-.TH GVPE 5 "2005-03-18" "1.8" "GNU Virtual Private Ethernet"
+.TH GVPE 5 "2013-07-10" "2.24" "GNU Virtual Private Ethernet"
+.\" For nroff, turn off justification. Always turn off hyphenation; it makes
+.\" way too many mistakes in technical documents.
+.if n .ad l
+.nh
.SH "NAME"
GNU\-VPE \- Overview of the GNU Virtual Private Ethernet suite.
.SH "DESCRIPTION"
@@ -137,11 +136,11 @@
\&\s-1GVPE\s0 is a suite designed to provide a virtual private network for multiple
nodes over an untrusted network. This document first gives an introduction
to VPNs in general and then describes the specific implementation of \s-1GVPE\s0.
-.Sh "\s-1WHAT\s0 \s-1IS\s0 A \s-1VPN\s0?"
+.SS "\s-1WHAT\s0 \s-1IS\s0 A \s-1VPN\s0?"
.IX Subsection "WHAT IS A VPN?"
\&\s-1VPN\s0 is an acronym, it stands for:
-.IP "\(bu" 4
-.IX Xref "Virtual"
+.IP "Virtual" 4
+.IX Item "Virtual"
Virtual means that no physical network is created (of course), but a
network is \fIemulated\fR by creating multiple tunnels between the member
nodes by encapsulating and sending data over another transport network.
@@ -149,8 +148,8 @@
Usually the emulated network is a normal \s-1IP\s0 or Ethernet, and the transport
network is the Internet. However, using a \s-1VPN\s0 system like \s-1GVPE\s0 to connect
nodes over other untrusted networks such as Wireless \s-1LAN\s0 is not uncommon.
-.IP "\(bu" 4
-.IX Xref "Private"
+.IP "Private" 4
+.IX Item "Private"
Private means that non-participating nodes cannot decode (\*(L"sniff)\*(R" nor
inject (\*(L"spoof\*(R") packets. This means that nodes can be connected over
untrusted networks such as the public Internet without fear of being
@@ -160,18 +159,18 @@
In the case of \s-1GVPE\s0, even participating nodes cannot sniff packets
send to other nodes or spoof packets as if sent from other nodes, so
communications between any two nodes is private to those two nodes.
-.IP "\(bu" 4
-.IX Xref "Network"
+.IP "Network" 4
+.IX Item "Network"
Network means that more than two parties can participate in the network,
so for instance it's possible to connect multiple branches of a company
-into a single network. Many so-called \*(L"vpn\*(R" solutions only create
+into a single network. Many so-called \*(L"\s-1VPN\s0\*(R" solutions only create
point-to-point tunnels, which in turn can be used to build larger
networks.
.Sp
-\&\s-1GVPE\s0 provides a true multi-point network in wich any number of nodes (at
+\&\s-1GVPE\s0 provides a true multi-point network in which any number of nodes (at
least a few dozen in practise, the theoretical limit is 4095 nodes) can
participate.
-.Sh "\s-1GVPE\s0 \s-1DESIGN\s0 \s-1GOALS\s0"
+.SS "\s-1GVPE\s0 \s-1DESIGN\s0 \s-1GOALS\s0"
.IX Subsection "GVPE DESIGN GOALS"
.IP "\s-1SIMPLE\s0 \s-1DESIGN\s0" 4
.IX Item "SIMPLE DESIGN"
@@ -197,94 +196,92 @@
another host.
.SH "PROGRAMS"
.IX Header "PROGRAMS"
-Vpe comes with two programs: one daemon (\f(CW\*(C`gvpe\*(C'\fR) and one control program
+Gvpe comes with two programs: one daemon (\f(CW\*(C`gvpe\*(C'\fR) and one control program
(\f(CW\*(C`gvpectrl\*(C'\fR).
.IP "gvpectrl" 4
.IX Item "gvpectrl"
-Is used to generate the keys, check and give an overview of of the
-configuration and contorl the daemon (restarting etc.).
+This program is used to generate the keys, check and give an overview of of the
+configuration and to control the daemon (restarting etc.).
.IP "gvpe" 4
.IX Item "gvpe"
-Is the daemon used to establish and maintain connections to the other
-network members. It should be run on the gateway machine.
+This is the daemon used to establish and maintain connections to the other
+network nodes. It should be run on the gateway of each \s-1VPN\s0 subnet.
.SH "COMPILETIME CONFIGURATION"
.IX Header "COMPILETIME CONFIGURATION"
Please have a look at the \f(CW\*(C`gvpe.osdep(5)\*(C'\fR manpage for platform-specific
information.
.PP
+Gvpe hardcodes most encryption parameters. While this reduces flexibility,
+it makes the program much simpler and helps making buffer overflows
+impossible under most circumstances.
+.PP
Here are a few recipes for compiling your gvpe, showing the extremes
-(fast, small, insecure \s-1OR\s0 slow, large, more secure), between you should
-choose:
-.Sh "\s-1AS\s0 \s-1LOW\s0 \s-1PACKET\s0 \s-1OVERHEAD\s0 \s-1AS\s0 \s-1POSSIBLE\s0"
+(fast, small, insecure \s-1OR\s0 slow, large, more secure), between which you
+should choose:
+.SS "\s-1AS\s0 \s-1LOW\s0 \s-1PACKET\s0 \s-1OVERHEAD\s0 \s-1AS\s0 \s-1POSSIBLE\s0"
.IX Subsection "AS LOW PACKET OVERHEAD AS POSSIBLE"
.Vb 1
-\& ./configure --enable-hmac-length=4 --enable-rand-length=0
+\& ./configure \-\-enable\-hmac\-length=4 \-\-enable\-rand\-length=0
.Ve
.PP
Minimize the header overhead of \s-1VPN\s0 packets (the above will result in
only 4 bytes of overhead over the raw ethernet frame). This is a insecure
-configuration because a \s-1HMAC\s0 length of 4 makes collision attacks based on
-the birthday paradox easy, though.
-.Sh "\s-1MINIMIZE\s0 \s-1CPU\s0 \s-1TIME\s0 \s-1REQUIRED\s0"
+configuration because a \s-1HMAC\s0 length of 4 makes collision attacks almost
+trivial.
+.SS "\s-1MINIMIZE\s0 \s-1CPU\s0 \s-1TIME\s0 \s-1REQUIRED\s0"
.IX Subsection "MINIMIZE CPU TIME REQUIRED"
.Vb 1
-\& ./configure --enable-cipher=bf --enable-digest=md4
+\& ./configure \-\-enable\-cipher=bf \-\-enable\-digest=md4
.Ve
.PP
Use the fastest cipher and digest algorithms currently available in
-gvpe. \s-1MD4\s0 has been broken and is quite insecure, though.
-.Sh "\s-1MAXIMIZE\s0 \s-1SECURITY\s0"
+gvpe. \s-1MD4\s0 has been broken and is quite insecure, though, so using another
+digest algorithm is recommended.
+.SS "\s-1MAXIMIZE\s0 \s-1SECURITY\s0"
.IX Subsection "MAXIMIZE SECURITY"
.Vb 1
-\& ./configure --enable-hmac-length=16 --enable-rand-length=8 --enable-digest=sha1
+\& ./configure \-\-enable\-hmac\-length=16 \-\-enable\-rand\-length=12 \-\-enable\-digest=ripemd610
.Ve
.PP
This uses a 16 byte \s-1HMAC\s0 checksum to authenticate packets (I guess 8\-12
would also be pretty secure ;) and will additionally prefix each packet
-with 8 bytes of random data. In the long run, people should move to
-\&\s-1SHA\-224\s0 and beyond, but support in openssl is missing as of writing this
-document.
+with 12 bytes of random data.
.PP
-In general, remember that \s-1AES\-128\s0 seems to be more secure and faster than
+In general, remember that \s-1AES\-128\s0 seems to be as secure but faster than
\&\s-1AES\-192\s0 or \s-1AES\-256\s0, more randomness helps against sniffing and a longer
-\&\s-1HMAC\s0 helps against spoofing. \s-1MD4\s0 is a fast digest, \s-1SHA1\s0 or \s-1RIPEMD160\s0 are
-better, and Blowfish is a fast cipher (and also quite secure).
+\&\s-1HMAC\s0 helps against spoofing. \s-1MD4\s0 is a fast digest, \s-1SHA1\s0, \s-1RIPEMD160\s0, \s-1SHA256\s0
+are consecutively better, and Blowfish is a fast cipher (and also quite
+secure).
.SH "HOW TO SET UP A SIMPLE VPN"
.IX Header "HOW TO SET UP A SIMPLE VPN"
In this section I will describe how to get a simple \s-1VPN\s0 consisting of
three hosts up and running.
-.Sh "\s-1STEP\s0 1: configuration"
+.SS "\s-1STEP\s0 1: configuration"
.IX Subsection "STEP 1: configuration"
-First you have to create a daemon configuation file and put it into the
+First you have to create a daemon configuration file and put it into the
configuration directory. This is usually \f(CW\*(C`/etc/gvpe\*(C'\fR, depending on how you
-configured gvpe, and can be overwritten using the \f(CW\*(C`\-c\*(C'\fR commandline switch.
+configured gvpe, and can be overwritten using the \f(CW\*(C`\-c\*(C'\fR command line switch.
.PP
Put the following lines into \f(CW\*(C`/etc/gvpe/gvpe.conf\*(C'\fR:
.PP
.Vb 3
-\& udp-port = 50000 # the external port to listen on (configure your firewall)
+\& udp\-port = 50000 # the external port to listen on (configure your firewall)
\& mtu = 1400 # minimum MTU of all outgoing interfaces on all hosts
\& ifname = vpn0 # the local network device name
-.Ve
-.PP
-.Vb 2
+\&
\& node = first # just a nickname
\& hostname = first.example.net # the DNS name or IP address of the host
-.Ve
-.PP
-.Vb 2
+\&
\& node = second
\& hostname = 133.55.82.9
-.Ve
-.PP
-.Vb 2
+\&
\& node = third
\& hostname = third.example.net
.Ve
.PP
-The only other file neccessary if the \f(CW\*(C`if\-up\*(C'\fR script that initializes the
-local ethernet interface. Put the following lines into \f(CW\*(C`/etc/gvpe/if\-up\*(C'\fR
-and make it execute (\f(CW\*(C`chmod 755 /etc/gvpe/if\-up\*(C'\fR):
+The only other file necessary is the \f(CW\*(C`if\-up\*(C'\fR script that initializes the
+virtual ethernet interface on the local host. Put the following lines into
+\&\f(CW\*(C`/etc/gvpe/if\-up\*(C'\fR and make it executable (\f(CW\*(C`chmod 755 /etc/gvpe/if\-up\*(C'\fR):
.PP
.Vb 6
\& #!/bin/sh
@@ -296,70 +293,73 @@
.Ve
.PP
This script will give each node a different \s-1IP\s0 address in the \f(CW\*(C`10.0/16\*(C'\fR
-network. The internal network (e.g. the \f(CW\*(C`eth0\*(C'\fR interface) should then be
+network. The internal network (if gvpe runs on a router) should then be
set to a subset of that network, e.g. \f(CW\*(C`10.0.1.0/24\*(C'\fR on node \f(CW\*(C`first\*(C'\fR,
\&\f(CW\*(C`10.0.2.0/24\*(C'\fR on node \f(CW\*(C`second\*(C'\fR, and so on.
.PP
By enabling routing on the gateway host that runs \f(CW\*(C`gvpe\*(C'\fR all nodes will
-be able to reach the other nodes. You can, of course, also use proxy arp
-or other means of pseudo-bridging (or even real briding), or (best) full
-routing \- the choice is yours.
-.Sh "\s-1STEP\s0 2: create the \s-1RSA\s0 key pairs for all hosts"
+be able to reach the other nodes. You can, of course, also use proxy \s-1ARP\s0
+or other means of pseudo-bridging, or (best) full routing \- the choice is
+yours.
+.SS "\s-1STEP\s0 2: create the \s-1RSA\s0 key pairs for all hosts"
.IX Subsection "STEP 2: create the RSA key pairs for all hosts"
-Run the following command to generate all key pairs (that might take a
-while):
+Run the following command to generate all key pairs for all nodes (that
+might take a while):
.PP
.Vb 1
-\& gvpectrl -c /etc/gvpe -g
+\& gvpectrl \-c /etc/gvpe \-g
.Ve
.PP
This command will put the public keys into \f(CW\*(C`/etc/gvpe/pubkeys/\f(CInodename\f(CW\*(C'\fR and the private keys into \f(CW\*(C`/etc/gvpe/hostkeys/\f(CInodename\f(CW\*(C'\fR.
-.Sh "\s-1STEP\s0 3: distribute the config files to all nodes"
+.SS "\s-1STEP\s0 3: distribute the config files to all nodes"
.IX Subsection "STEP 3: distribute the config files to all nodes"
-Now distribute the config files to the other nodes. This should be done in two steps, since the
-private keys should not be distributed. The example uses rsync-over-ssh
+Now distribute the config files and private keys to the other nodes. This
+should be done in two steps, since only the private keys meant for a node
+should be distributed (so each node has only it's own private key).
+.PP
+The example uses rsync-over-ssh
.PP
First all the config files without the hostkeys should be distributed:
.PP
.Vb 3
-\& rsync -avzessh /etc/gvpe first.example.net:/etc/. --exclude hostkeys
-\& rsync -avzessh /etc/gvpe 133.55.82.9:/etc/. --exclude hostkeys
-\& rsync -avzessh /etc/gvpe third.example.net:/etc/. --exclude hostkeys
+\& rsync \-avzessh /etc/gvpe first.example.net:/etc/. \-\-exclude hostkeys
+\& rsync \-avzessh /etc/gvpe 133.55.82.9:/etc/. \-\-exclude hostkeys
+\& rsync \-avzessh /etc/gvpe third.example.net:/etc/. \-\-exclude hostkeys
.Ve
.PP
Then the hostkeys should be copied:
.PP
.Vb 3
-\& rsync -avzessh /etc/gvpe/hostkeys/first first.example.net:/etc/hostkey
-\& rsync -avzessh /etc/gvpe/hostkeys/second 133.55.82.9:/etc/hostkey
-\& rsync -avzessh /etc/gvpe/hostkeys/third third.example.net:/etc/hostkey
+\& rsync \-avzessh /etc/gvpe/hostkeys/first first.example.net:/etc/hostkey
+\& rsync \-avzessh /etc/gvpe/hostkeys/second 133.55.82.9:/etc/hostkey
+\& rsync \-avzessh /etc/gvpe/hostkeys/third third.example.net:/etc/hostkey
.Ve
.PP
-You should now check the configration by issuing the command \f(CW\*(C`gvpectrl \-c
+You should now check the configuration by issuing the command \f(CW\*(C`gvpectrl \-c
/etc/gvpe \-s\*(C'\fR on each node and verify it's output.
-.Sh "\s-1STEP\s0 4: starting gvpe"
+.SS "\s-1STEP\s0 4: starting gvpe"
.IX Subsection "STEP 4: starting gvpe"
You should then start gvpe on each node by issuing a command like:
.PP
.Vb 1
-\& gvpe -D -linfo first # first is the nodename
+\& gvpe \-D \-l info first # first is the nodename
.Ve
.PP
-This will make the gvpe stay in foreground. You should then see
+This will make the gvpe daemon stay in foreground. You should then see
\&\*(L"connection established\*(R" messages. If you don't see them check your
firewall and routing (use tcpdump ;).
.PP
If this works you should check your networking setup by pinging various
endpoints.
.PP
-To make gvpe run more permanently you can either run it as a daemon
-(by starting it without the \f(CW\*(C`\-D\*(C'\fR switch), or, much better, from your
-inittab. I use a line like this on my systems:
+To make gvpe run more permanently you can either run it as a daemon (by
+starting it without the \f(CW\*(C`\-D\*(C'\fR switch), or, much better, from your inittab
+or equivalent. I use a line like this on all my systems:
.PP
.Vb 1
-\& t1:2345:respawn:/opt/gvpe/sbin/gvpe -D -L first >/dev/null 2>&1
+\& t1:2345:respawn:/opt/gvpe/sbin/gvpe \-D \-L first >/dev/null 2>&1
.Ve
-.Sh "\s-1STEP\s0 5: enjoy"
+.SS "\s-1STEP\s0 5: enjoy"
.IX Subsection "STEP 5: enjoy"
\&... and play around. Sending a \-HUP (\f(CW\*(C`gvpectrl \-kHUP\*(C'\fR) to the daemon
will make it try to connect to all other nodes again. If you run it from
@@ -368,11 +368,11 @@
again.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
-\&\fIgvpe.osdep\fR\|(5) for OS-depedendent information, \fIgvpe.conf\fR\|(5), \fIgvpectrl\fR\|(8),
+\&\fIgvpe.osdep\fR\|(5) for OS-dependent information, \fIgvpe.conf\fR\|(5), \fIgvpectrl\fR\|(8),
and for a description of the transports, protocol, and routing algorithm,
\&\fIgvpe.protocol\fR\|(7).
.PP
-The \s-1GVPE\s0 mailinglist, at , or
+The \s-1GVPE\s0 mailing list, at , or
\&\f(CW\*(C`gvpe@lists.schmorp.de\*(C'\fR.
.SH "AUTHOR"
.IX Header "AUTHOR"