DOKK / manpages / debian 12 / uanytun / uanytun.8.en
UANYTUN(8)   UANYTUN(8)

uanytun - micro anycast tunneling daemon

uanytun


  [ -h|--help ]


  [ -D|--nodaemonize ]


  [ -u|--username <username> ]


  [ -g|--groupname <groupname> ]


  [ -C|--chroot <path> ]


  [ -P|--write-pid <filename> ]


  [ -L|--log <target>:<level>[,<param1>[,<param2>[..]]] ]


  [ -U|--debug ]


  [ -i|--interface <ip-address> ]


  [ -p|--port <port> ]


  [ -r|--remote-host <hostname|ip> ]


  [ -o|--remote-port <port> ]


  [ -4|--ipv4-only ]


  [ -6|--ipv6-only ]


  [ -d|--dev <name> ]


  [ -t|--type <tun|tap> ]


  [ -n|--ifconfig <local>/<prefix> ]


  [ -x|--post-up-script <script> ]


  [ -m|--mux <mux-id> ]


  [ -s|--sender-id <sender id> ]


  [ -w|--window-size <window size> ]


  [ -k|--kd-prf <kd-prf type> ]


  [ -e|--role <role> ]


  [ -E|--passphrase <pass phrase> ]


  [ -K|--key <master key> ]


  [ -A|--salt <master salt> ]


  [ -c|--cipher <cipher type> ]


  [ -a|--auth-algo <algo type> ]


  [ -b|--auth-tag-length <length> ]

uAnytun is a tiny implementation of the Secure Anycast Tunneling Protocol (SATP). It provides a complete VPN solution similar to OpenVPN or IPsec in tunnel mode. The main difference is that anycast enables the setup of tunnels between an arbitrary combination of anycast, unicast and multicast hosts. Unlike Anytun which is a full featured implementation uAnytun has no support for multiple connections or synchronisation. It is a small single threaded implementation intended to act as a client on small platforms.

uAnytun has been designed as a peer to peer application, so there is no difference between client and server. The following options can be passed to the daemon:

-D, --nodaemonize

This option instructs uAnytun to run in foreground instead of becoming a daemon which is the default.

-u, --username <username>

run as this user. If no group is specified (-g) the default group of the user is used. The default is to not drop privileges.

-g, --groupname <groupname>

run as this group. If no username is specified (-u) this gets ignored. The default is to not drop privileges.

-C, --chroot <path>

Instruct uAnytun to run in a chroot jail. The default is to not run in chroot.

-P, --write-pid <filename>

Instruct uAnytun to write it’s pid to this file. The default is to not create a pid file.

-L, --log <target>:<level>[,<param1>[,<param2>[..]]]

add log target to logging system. This can be invoked several times in order to log to different targets at the same time. Every target has its own log level which is a number between 0 and 5. Where 0 means disabling log and 5 means debug messages are enabled.

The file target can be used more than once with different levels. If no target is provided at the command line a single target with the config syslog:3,uanytun,daemon is added.

The following targets are supported:

syslog

log to syslog daemon, parameters <level>[,<logname>[,<facility>]]

file

log to file, parameters <level>[,<path>]

stdout

log to standard output, parameters <level>

stderr

log to standard error, parameters <level>

-U, --debug

This option instructs uAnytun to run in debug mode. It implicits -D (don’t daemonize) and adds a log target with the configuration stdout:5 (logging with maximum level). In future releases there might be additional output when this option is supplied.

-i, --interface <ip address>

This IP address is used as the sender address for outgoing packets. The default is to not use a special interface and just bind on all interfaces.

-p, --port <port>

The local UDP port that is used to send and receive the payload data. The two tunnel endpoints can use different ports. default: 4444

-r, --remote-host <hostname|ip>

This option can be used to specify the remote tunnel endpoint. In case of anycast tunnel endpoints, the anycast IP address has to be used. If you do not specify an address, it is automatically determined after receiving the first data packet.

-o, --remote-port <port>

The UDP port used for payload data by the remote host (specified with -p on the remote host). If you do not specify a port, it is automatically determined after receiving the first data packet.

-4, --ipv4-only

Resolv to IPv4 addresses only. The default is to resolv both IPv4 and IPv6 addresses.

-6, --ipv6-only

Resolv to IPv6 addresses only. The default is to resolv both IPv4 and IPv6 addresses.

-d, --dev <name>

device name

By default, tapN is used for Ethernet tunnel interfaces, and tunN for IP tunnels, respectively. This option can be used to manually override these defaults.

-t, --type <tun|tap>

device type

Type of the tunnels to create. Use tap for Ethernet tunnels, tun for IP tunnels.

-n, --ifconfig <local>/<prefix>

The local IP address and prefix length. The remote tunnel endpoint has to use a different IP address in the same subnet.

<local>

the local IP address for the tun/tap device

<prefix>

the prefix length of the network

-x, --post-up-script <script>

This option instructs uAnytun to run this script after the interface is created. By default no script will be executed.

-m, --mux <mux-id>

the multiplex id to use. default: 0

-s, --sender-id <sender id>

Each anycast tunnel endpoint needs a unique sender id (1, 2, 3, ...). It is needed to distinguish the senders in case of replay attacks. As uAnytun does not support synchronisation it can’t be used as an anycast endpoint therefore this option is quite useless but implemented for compatibility reasons. default: 0

-w, --window-size <window size>

seqence window size

Sometimes, packets arrive out of order on the receiver side. This option defines the size of a list of received packets' sequence numbers. If, according to this list, a received packet has been previously received or has been transmitted in the past, and is therefore not in the list anymore, this is interpreted as a replay attack and the packet is dropped. A value of 0 deactivates this list and, as a consequence, the replay protection employed by filtering packets according to their secuence number. By default the sequence window is disabled and therefore a window size of 0 is used.

-k, --kd—prf <kd-prf type>

key derivation pseudo random function

The pseudo random function which is used for calculating the session keys and session salt.

Possible values:

null

no random function, keys and salt are set to 0..00

aes-ctr

AES in counter mode with 128 Bits, default value

aes-ctr-128

AES in counter mode with 128 Bits

aes-ctr-192

AES in counter mode with 192 Bits

aes-ctr-256

AES in counter mode with 256 Bits

-e, --role <role>

SATP uses different session keys for inbound and outbound traffic. The role parameter is used to determine which keys to use for outbound or inbound packets. On both sides of a vpn connection different roles have to be used. Possible values are left and right. You may also use alice or server as a replacement for left and bob or client as a replacement for right. By default left is used.

-E, --passphrase <pass phrase>

This passphrase is used to generate the master key and master salt. For the master key the last n bits of the SHA256 digest of the passphrase (where n is the length of the master key in bits) is used. The master salt gets generated with the SHA1 digest. You may force a specific key and or salt by using --key and --salt.

-K, --key <master key>

master key to use for key derivation

Master key in hexadecimal notation, e.g. 01a2b3c4d5e6f708a9b0cadbecfd0fa1, with a mandatory length of 32, 48 or 64 characters (128, 192 or 256 bits).

-A, --salt <master salt>

master salt to use for key derivation

Master salt in hexadecimal notation, e.g. 01a2b3c4d5e6f708a9b0cadbecfd, with a mandatory length of 28 characters (14 bytes).

-c, --cipher <cipher type>

payload encryption algorithm

Encryption algorithm used for encrypting the payload

Possible values:

null

no encryption

aes-ctr

AES in counter mode with 128 Bits, default value

aes-ctr-128

AES in counter mode with 128 Bits

aes-ctr-192

AES in counter mode with 192 Bits

aes-ctr-256

AES in counter mode with 256 Bits

-a, --auth-algo <algo type>

message authentication algorithm

This option sets the message authentication algorithm.

If HMAC-SHA1 is used, the packet length is increased. The additional bytes contain the authentication data. see --auth-tag-length for more info.

Possible values:

null

no message authentication

sha1

HMAC-SHA1, default value

-b, --auth-tag-length <length>

The number of bytes to use for the auth tag. This value defaults to 10 bytes unless the null auth algo is used in which case it defaults to 0.

Host A:

uanytun -r hostb.example.com -t tun -n 192.168.123.1/30 -c aes-ctr-256 -k aes-ctr-256 -E have_a_very_safe_and_productive_day -e left

Host B:

uanytun -r hosta.example.com -t tun -n 192.168.123.2/30 -c aes-ctr-256 -k aes-ctr-256 -E have_a_very_safe_and_productive_day -e right

Unicast tunnel endpoint:

uanytun -r anycast.anytun.org -d anytun0 -t tun -n 192.0.2.2/30 -a null -c null -w 0 -e client

Anycast tunnel endpoints:

As uAnytun can’t work as an anycast endpoint it can’t be used for this purpose. You have to use Anytun for that job.

Most likely there are some bugs in uAnytun. If you find a bug, please let the developers know at uanytun@anytun.org. Of course, patches are preferred.

Christian Pointner <equinox@anytun.org>

Main web site: http://www.anytun.org/

Copyright (C) 2008-2014 Christian Pointner. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or any later version.

06/08/2018