doc/developer.texi

   1 @node Developer
   2 @unnumbered Developer manual
   3
   4 Pay attention how to get @ref{Sources, development source code}.
   5
   6 @table @asis
   7 @item Data encryption
   8     @url{https://cr.yp.to/chacha.html, ChaCha20}.
   9 @item Message authentication
  10     @url{https://cr.yp.to/mac.html, Poly1305}.
  11 @item Nonce and identity obfuscation
  12     @url{https://blake2.net/, BLAKE2b-MAC}.
  13 @item Password authenticated key agreement
  14     DH-A-EKE powered by @url{https://cr.yp.to/ecdh.html, Curve25519}
  15     and @url{https://ed25519.cr.yp.to/, Ed25519}.
  16 @item DH elliptic-curve point encoding for public keys
  17     @url{https://elligator.cr.yp.to/, Elligator}.
  18 @item Verifier password hashing algorithm
  19     @url{https://crypto.stanford.edu/balloon/, Balloon hashing} based
  20     on BLAKE2b-256.
  21 @item Encryptionless confidentiality preserving encoding
  22     @url{http://people.csail.mit.edu/rivest/chaffing-980701.txt,
  23     Chaffing-and-Winnowing} (two Poly1305 MACs for each bit of message)
  24     over 128 bits of
  25     @url{http://theory.lcs.mit.edu/~cis/pubs/rivest/fusion.ps,
  26     All-Or-Nothing-Transformed} (based on
  27     @url{http://cseweb.ucsd.edu/~mihir/papers/oaep.html, OAEP} using
  28     ChaCha20 with BLAKE2b-256 based
  29     @url{http://crypto.stanford.edu/~dabo/abstracts/saep.html, SAEP+}
  30     checksums) data with 128-bits of feeded random.
  31 @item Packet overhead
  32     25 bytes per packet. Plus 4128 bytes and noise in encryptionless mode.
  33 @item Handshake overhead
  34     4 UDP (2 from client, 2 from server) packets (round-trips for TCP).
  35     264 bytes total payload, 20680 in encryptionless mode.
  36 @item Entropy required
  37     832 bits in average on client, 832 bits in average on server side
  38     per handshake. 128 bits for each outgoing packet in encryptionless
  39     mode.
  40 @end table
  41
  42 @menu
  43 * Verifier structure::
  44 * Transport protocol: Transport.
  45 * Handshake protocol: Handshake.
  46 @end menu
  47
  48 @include verifierstruct.texi
  49 @include transport.texi
  50 @include handshake.texi