  DConnect(R) Daemon


  ____________________________________________________________

  Table of Contents


  1. What is it?

  2. Features.

     2.1 Present features.
     2.2 ToDo list.

  3. License.

  4. Installation.

     4.1 Requirements.
     4.2 Instalation.
     4.3 Config File.

  5. Know bugs.

  6. Direct Connect Protocol.

  7. Authors.



  ______________________________________________________________________

  11..  WWhhaatt iiss iitt??


  DConnect Daemon is a Direct Connect (from NeoModus Software) Hub clone
  for Linux. We created him, because we wanted to have stable program
  for stable system. It working as a system deamon.

  You can find newest version of DConnect Deamon on website
  <http://www.dc.ds.pg.gda.pl>

  22..  FFeeaattuurreess..

  22..11..  PPrreesseenntt ffeeaattuurreess..


  fast, pure C implementation

  libwrap support (hosts.allow, hosts.deny)

  low memory per user consumption

  uses threads (no forking)

  nick pattern matching

  22..22..  TTooDDoo lliisstt..


  documentation

  full protocol implementation:


  +o  key checking

  +o  passive mode: search/transfer query, search result

  +o  op list

  +o  admin user with pass

  +o  kick

  +o  temporal/permanent ban (?)

  +o  redirecting

  +o  hub net: MultiSearch, MultiConnectToMe

  logging:

  +o  level from config

  +o  put public chat, private chat, server dialogs, etc.... to separate
     logs

  +o  logfile location from config

  +o  debug level and support

  config file parser

  remote FTP/HTTP client interface (?)

  statistics output with HTML/SQL or something

  ports to other systems

  scripting (perl, tcl, etc.)

  IPv6 support (? is it possible ?)

  scripts for Debian, RedHat, etc. ...

  virtual hosts

  redirect support

  administration:

  +o  telnet console

  +o  web browser console

  +o  admin account

  security:

  +o  chroot

  +o  user to run from command-line option

  +o  allow to pick user/group by name in config

  33..  LLiicceennssee..

  GGNNUU GGEENNEERRAALL PPUUBBLLIICC LLIICCEENNSSEE Version 2, June 1991


  Copyright (C) 1989, 1991 Free Software Foundation, Inc.  59
  TemplePlace, Suite 330, Boston, MA 02111-1307 USA Everyone is
  permitted to copy and distribute verbatim copies of this license
  document, but changing it is not allowed.

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  44..  IInnssttaallllaattiioonn..

  44..11..  RReeqquuiirreemmeennttss..

  To compile DConnect Daemon, you will need:


  libwrap

  libpthread

  automake

  autoconf

  libtool

  gettext (not used now...)

  44..22..  IInnssttaallaattiioonn..

  In most cases this procedure should work:


  $ cd dcd-0.0.3

  $ ./configure

  $ make

  $ make install



  You may propably use some traditional configure options. There are no
  dcd-specific options, so don't worry about it.

  44..33..  CCoonnffiigg FFiillee..

  Config file _d_c_h_u_b_._c_o_n_f is located in _/_e_t_c_/_d_c_d _f_o_l_d_e_r. There is located
  config example after installation. Some options from this file  are
  ignored yet. Don't touch this while the hub is running (for now)

  Parameters in dchub.conf

  GGeenneerraall OOppttiioonnss::

  _l_i_s_t_e_n_i_n_g___p_o_r_t - default is 411

  _d_a_e_m_o_n _= _0 - if you don't want to start DCD as deamon, uncomment this
  line


  _u_s_e_r _= _6_5_5_3_4
  _g_r_o_u_p _= _6_5_5_3_4

  UID/GID - default it's nobody user/gruop, but it's not the best idea,
  because That user/group shouldn't own any file. But if you don't need
  any logs uncomment these lines.

  _l_o_g_f_i_l_e___l_o_c_a_t_i_o_n - Log file location. Not working option yet. Default
  is /var/log/dcd/dcd.log

  HHuubb ccoonnffiigguurraattiioonn::

  _h_u_b_n_a_m_e - Some name of your Hub. Default is "DConnect Daemon"

  _m_o_t_d - Some message of the day

  _u_s_e_r___l_i_m_i_t - Max amount of users you allow to connect to hub. Default
  is 1000

  _b_a_n - allow/deny users. Not implemented yet.

  _a_l_l_o_w___b_r_o_k_e_n___k_e_y - we don't yet check for a valid key, so this is
  ignored

  _p_i_n_g___t_i_m_e_o_u_t - How long hub's waiting for users.

  _r_e_g_i_s_t_e_r___t_i_m_e_o_u_t - Time for send authorization from user to hub (in
  seconds). Default is 30.

  _n_i_c_k_n_a_m_e___p_a_t_t_e_r_n - Users nick pattern, who's allow to connect to hub.
  See match.c for details on wildcards. Well, this should be done with
  regexp - now this is lame Example: _n_i_c_k_n_a_m_e___p_a_t_t_e_r_n _= _*_[_d_s_?_*_]  Default
  nickname_pattern = *

  _m_i_n___s_h_a_r_e - minimum shared data in megabytes. Default is 300

  _m_i_n___s_l_o_t_s - minimum number of slots. Not supported yet. Default is 4.


  55..  KKnnooww bbuuggss..

  We know that there are a lot of them...(this file is too short :).

  The most important are:

  some local buffer overflows

  user can not set names with national letters

  rehashing with -HUP doesn't work somehow

  hub name sent on publicmsg is hardcoded

  with NeoModus Direct Connect 1.0 preview Build 8 user list while
  logging is missing sometimes. Build 9 works fine.

  If you find any - tell us about it: dc-hub@ds.pg.gda.pl

  66..  DDiirreecctt CCoonnnneecctt PPrroottooccooll..


  CCrraacckkeedd bbyy AAllbbeerrtt

  Based on analysis source code of:


  DCJavaClient 0.20 (JJ) - 2001 - Stefan Grling - stefan@gorling.se
  (Java)

  Opendcd 0.2 (OO)- 2001 - suxxx@users.sourceforge.net (Kylix)

  DCHub 0.0.3 (HH) - Eric Prevoteau - www@ac2i.tzo.com (Linux C)


  NR     SRC     NAME AND STRUCTURE    DESCRIPTION
  1       HH            $$BBaaddPPaassss         Authorization failed (password sended _$_M_y_P_a_s_s instruction is bad). DDiirreeccttiioonn::
  ______________________________________________________________________
  1     JJ,,OO,,HH       $$CCoonnnneeccttTTooMMee        Not recognized yet
  ______________________________________________________________________
   2      JJ          $$DDiirreeccttiioonn         Not recognized yet
   3      JJ          $$FFiilleeLLeennggtthh        Information about size of file, which was asked _$_G_e_t command (during direct connection between clients). Thanks this clients which downloading data, know size of this data.
   4     JJ,,HH         $$FFoorrcceeMMoovvee         Demand of redirecting to other hub. It it was been possible to make balancing of load. (2 hubs and redirecting in dependence from size of shared data, hour of day or subnet from which client conecting)
   5      JJ             $$GGeett            Request about download, or resume of file (during direct connection between clients). Second client should answer command _$_F_i_l_e_L_e_n_g_t_h. After that we send command _$_S_e_n_d, starting transfer of data.
   6     JJ,,OO          $$GGeettIINNFFOO          Demand of client information. Hub analyses _n_i_c_k field, and sending command to destination client. Adressee should answer _$_M_y_I_N_F_O command.
   7     JJ,,OO        $$GGeettNNiicckkLLiisstt        Demand of nicks list of clients of hub. Hub answers command _$_N_i_c_k_L_i_s_t and _$_O_p_L_i_s_t.
   1     OO,,HH          $$GGeettPPaassss          Demand of authorization (check nick permissions). Client answers command _$_M_y_P_a_s_s with password.
   8     JJ,,OO           $$HHeelllloo           Information to everybody, that new client connected. Clients should answers command _$_M_y_I_N_F_O sending informations about itself to him(JJ).
  21      HH          $$HHuubbIIssFFuullll         Sending to client when hub is full and redirect is impossible.
   9     JJ,,HH          $$HHuubbNNaammee          Sending to just connected client of hub.
  10    JJ,,OO,,HH           $$KKeeyy            Answer of client on _$_L_o_c_k command (demand of authorization). Key _k_e_y is enumerated basis of client alghoritm and field _s_a_l_t. Field _s_a_l_t is sending on command _$_L_o_c_k.
   1     OO,,HH            $$KKiicckk          Kick from hub. Only admin can do that.
  11    JJ,,OO,,HH           $$LLoocckk           Demand of authorization. This is protection from unauthorized connection to hub.Algorithm of enumerating of key is fortunately already broken :)) In answer client sent to hub command _$_K_e_y with key, enumerated basis of field _s_a_l_t. Authorization is realized also during direct connection between clients (session download) into both side.Length of _s_a_l_t field is changing (less than 3 bytes - in (HH) length is drawing from range 50-100, and chars from range '%' - 'z'), however _p_r_i_v_a_t_e_K_e_y is not used in any analysed sources.
   1     OO,,HH          $$LLooggggeeddIInn         Authorization succcess. Password sending after command _$_M_y_P_a_s_s is correct. User is logged on hub.
  12      JJ           $$MMaaxxeeddOOuutt         Not recognized yet.
   1      OO         $$MMuullttiiSSeeaarrcchh        Not recognized yet.
  13     JJ,,OO           $$MMyyIINNFFOO          Information about itself. Hub records all parameters and sends this command to rest of clients. (added _$_A_L_L before - this means that exist version of _$_M_y_I_N_F_O for one client only.
  14      JJ            $$MMyyNNiicckk          Information about nick. This is first command, sended during direct connection between clients (download session).
  13     OO,,HH           $$MMyyPPaassss          Answer on _$_G_e_t_P_a_s_s command. That is nicks rights confirmation. If password is correct, hub sending command _$_H_e_l_l_o to all, with information about new user. If this user is OP, hub sending commands _$_L_o_g_g_e_d_I_n and _$_H_e_l_l_o to all. If password is incorrect, client is disconnecting (OO) or command _$_B_a_d_P_a_s_s (HH) is sending.
  15     JJ,,OO          $$NNiicckkLLiisstt         List all of nicks logged on hub (admin and user are not distinguished). This is answer of server onto command _$_G_e_t_N_i_c_k_L_i_s_t. Turned list is separated '$$'. User with admin rights, sees additionally user HubSecurity (first on turned list).
   4      OO         $$OOppFFoorrcceeMMoovvee        Demand of redirecting user with admin's rights to other hub.
  16     JJ,,OO           $$OOppLLiisstt          List of admins logged on hub. This is hub's answer on command_$_G_e_t_N_i_c_k_L_i_s_t.Turned nicks list is separated '$$'. User with admin rights, sees additionally user HubSecurity (first on turned list).
  17      JJ             $$QQuuiitt           Correct end of connection. Hub removes sender from nicks list, then sends command _$_Q_u_i_t to remaining users. (They can remove sender from own nicks list).
  18    JJ,,OO,,HH      $$RReevvCCoonnnneeccttTTooMMee      Not recognized yet
  19    JJ,,OO,,HH          $$SSeeaarrcchh          File searching. Hub may pass this command between itself.
  20      JJ             $$SSeenndd           Starting stream of data during download session (between clients). Sent previously command _$_G_e_t and _$_F_i_l_e_L_e_n_g_t_h define which file is sent, from which of byte and what portion of data is transmited.
  21    JJ,,OO,,HH            $$SSRR            Not recognized yet.
  22     JJ,,HH             $$TToo            Sending private message (on DC chat).
  23     JJ,,HH        $$VVaalliiddaatteeNNiicckk       Validation of nick. This command is sent to hub soon after _$_K_e_y command (on start of connection). Hub checks whether nick is not already used or banned. Chars ' ' and '$' are incorrect in nick. If nick is password protected, hub sends command _$_G_e_t_P_a_s_s to confirm rights to using nick. Hub sends _$_H_e_l_l_o information to everybody, that new client connected. (OO).
  24     JJ,,HH          $$VVeerrssiioonn          Information about client version. Currently is not used.



  77..  AAuutthhoorrss..

  And here We in alphabetical order:


  Michal "Fela" Felski MAIL

  +o  web site design

  Pawel "blues" Golaszewski MAIL

  +o  ac/am support

  +o  cvs support

  +o  packaging

  Sebastian "rawsock" Rosenkiewicz MAIL


  +o  network programming

  +o  protocol implementation

  Artur P. "ventox" Wojcik MAIL

  +o  framework

  +o  configuration

  Robert "Albert" Zoralski MAIL

  +o  protocol cracking





















































