mirror of
https://github.com/yarrick/iodine.git
synced 2024-11-22 21:16:07 +03:00
110 lines
4.3 KiB
Plaintext
110 lines
4.3 KiB
Plaintext
|
|
iodine - IP over DNS is now easy
|
|
|
|
http://code.kryo.se/iodine
|
|
|
|
********************************
|
|
|
|
This is a piece of software that lets you tunnel IPv4 data through a DNS
|
|
server. This can be usable in different situations where internet access is
|
|
firewalled, but DNS queries are allowed.
|
|
|
|
|
|
QUICKSTART:
|
|
|
|
Try it out within your own LAN! Follow these simple steps:
|
|
- On your server, run: ./iodined -f 10.0.0.1 test.asdf
|
|
(If you already use the 10.0.0.0 network, use another internal net like
|
|
172.16.0.0)
|
|
- On the client, run: ./iodine -f 192.168.0.1 test.asdf
|
|
(Replace 192.168.0.1 with the server's ip address)
|
|
- Now the client has the tunnel ip 10.0.0.2 and the server has 10.0.0.1
|
|
- Try pinging each other through the tunnel
|
|
- Done! :)
|
|
To actually use it through a relaying nameserver, see below.
|
|
|
|
|
|
HOW TO USE:
|
|
|
|
Server side:
|
|
To use this tunnel, you need control over a real domain (like mytunnel.com),
|
|
and a server with a static public IP number that does not yet run a DNS
|
|
server. Then, delegate a subdomain (say, tunnel1.mytunnel.com) to the server.
|
|
If you use BIND for the domain, add these lines to the zone file:
|
|
|
|
tunnel1host IN A 10.15.213.99
|
|
tunnel1 IN NS tunnel1host.mytunnel.com.
|
|
|
|
Now any DNS querys for domains ending with tunnel1.mytunnnel.com will be sent
|
|
to your server. Start iodined on the server. The first argument is the tunnel
|
|
IP address (like 192.168.99.1) and the second is the assigned domain (in this
|
|
case tunnel1.mytunnel.com). The -f argument will keep iodined running in the
|
|
foreground, which helps when testing. iodined will start a virtual interface,
|
|
and also start listening for DNS queries on UDP port 53. Now everything is
|
|
ready for the client.
|
|
|
|
Client side:
|
|
All the setup is done, just start iodine. It also takes two
|
|
arguments, the first is the local relaying DNS server and the second is the
|
|
domain used (tunnel1.mytunnnel.com). If DNS queries are allowed to any
|
|
computer, you can use the tunnel endpoint (example: 10.15.213.99 or
|
|
tunnel1host.mytunnel.com) as the first argument. The tunnel interface will get
|
|
an IP close to the servers (in this case 192.168.99.2) and a suitable MTU. Now
|
|
you should be able to ping the other end of the tunnel from either side.
|
|
|
|
|
|
MISC. INFO:
|
|
|
|
Note that you can have only one client per server at the same time. This is
|
|
because of the fragmentation of big packets going upstream, and will be fixed
|
|
in future versions.
|
|
|
|
Try experimenting with the MTU size (-m option) to get maximum bandwidth. It is
|
|
set to 1024 by default, which seems to work with most DNS servers. If you have
|
|
problems, try setting it to below 512.
|
|
|
|
If you have problems, try inspecting the traffic with network monitoring tools
|
|
and make sure that the relaying DNS server has not cached the response. A
|
|
cached error message could mean that you started the client before the server.
|
|
|
|
The upstream data is sent gzipped encoded in hexadecimal. DNS protocol allows
|
|
one query per packet, and one query can be max 256 chars. Each domain name part
|
|
can be max 63 chars. So your domain name and subdomain should be as short as
|
|
possible to allow maximum throughput.
|
|
|
|
|
|
PORTABILITY:
|
|
|
|
iodine has been tested on Linux (x86 and SPARC64), FreeBSD (x86), OpenBSD (x86)
|
|
and MacOS X (10.3, ppc, with http://www-user.rhrk.uni-kl.de/~nissler/tuntap/).
|
|
It should work on other unix-like systems as well that has TUN/TAP tunneling
|
|
support. Let us know if you get it to run on other platforms.
|
|
|
|
|
|
THE NAME:
|
|
|
|
The name iodine was chosen since it starts with IOD (IP Over DNS) and since
|
|
iodine has atomic number 53, which happens to be the DNS port number.
|
|
|
|
|
|
THANKS:
|
|
|
|
- To kuxien for FreeBSD and OS X testing
|
|
|
|
|
|
AUTHORS & LICENSE:
|
|
|
|
Copyright (c) 2006 Bjorn Andersson <flex@kryo.se>, Erik Ekman <yarrick@kryo.se>
|
|
|
|
Permission to use, copy, modify, and distribute this software for any purpose
|
|
with or without fee is hereby granted, provided that the above copyright notice
|
|
and this permission notice appear in all copies.
|
|
|
|
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
|
|
REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
|
|
FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
|
|
INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
|
|
LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
|
|
OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
|
|
PERFORMANCE OF THIS SOFTWARE.
|