2 @subsection Encryptionless mode
4 Some jurisdictions can force user to reveal his encryption keys. However
5 they can not ask for authentication (signing) keys. So you are safe to
6 use authentication algorithms, but not the encryption ones. Moreover
7 some countries forbids usage of encryption (but again not the
10 GoVPN provides special encryptionless mode of operation. In this mode it
11 replaces ChaCha20 function used for confidentiality with rather
12 well-known @url{http://people.csail.mit.edu/rivest/chaffing-980701.txt,
13 Chaffing-and-Winnowing} (CnW) technology. This is rather traffic and
14 resource hungry algorithm, so we use it after
15 @url{http://theory.lcs.mit.edu/~cis/pubs/rivest/fusion.ps,
16 All-Or-Nothing-Transformation} (based on
17 @url{http://cseweb.ucsd.edu/~mihir/papers/oaep.html, Optimal Asymmetric
18 Encryption Padding}) on the data. This is confidentiality preserving
21 AONT is just a keyless encoding of the data. CnW uses only
22 authentication function. Handshake additionally uses Diffie-Hellman and
23 signature algorithms. No encryption and steganography involved.
25 In this mode each outgoing packet became larger on 4128 bytes and
26 @ref{Noise, noise} is forcefully enabled. So this is resource hungry mode!
28 See @code{govpn/cnw} and @code{govpn/aont} packages for details of AONT
29 and chaffing operations.