servlink/README

   1 Servlink protocol documentation.
   2 $Id: README 1285 2006-05-05 15:03:53Z nenolod $
   3 --------------
   4
   5 After negotiating an incoming/outgoing server connection, the ircd will
   6 fork, then execve servlink, with fd 0 as one end of a control pipe and
   7 fd 1 as one end of a data pipe. fd 2 will be the socket connected to
   8 the remote server.
   9
  10 The data pipe is used by the ircd to send/receive normal, decrypted,
  11 uncompressed IRC commands to/from the remote server.  The socket is used to
  12 send the (processed) data to the remote server, and receive the data from
  13 the remote server.
  14
  15 The control pipe is used to activate encryption/compression and to set the
  16 encryption key/algorithm to be used.
  17
  18 Format of control messages:
  19
  20 <u8 command><optional data>
  21
  22 data format:
  23 <u16 len><data>
  24
  25 Commands:
  26
  27 001 - SET_ZIP_OUT_LEVEL
  28         data: yes
  29         description:
  30                 set compression level (0 [use default, 6], or 1-9)
  31
  32 002 - START_ZIP_OUT
  33         data: no
  34         description:
  35                 all data written to the data pipe will be compressed
  36                 prior to being sent to the remote server.
  37
  38 003 - START_ZIP_IN
  39         data: no
  40         description:
  41                 all data not yet read from the slink program will be
  42                 decompressed before reading
  43
  44 004 - INJECT_RECVQ
  45         data: recvq
  46
  47         Used before INIT to inject any data read from the server fd which
  48         should be pre-processed by servlink before being sent back
  49         to the LOCAL_FD through the data fd.
  50
  51 005 - INJECT_SENDQ
  52         data: sendq
  53
  54         As above, but sent to remote server without processing.
  55
  56 006 - INIT
  57
  58 007 - ZIPSTATS
  59         request to send ziplinks statistics reply.
  60
  61 replies
  62
  63 001 - ERROR
  64         data: u32 len/char error[len]
  65
  66         fatal error message.
  67
  68 002 - ZIPSTATS
  69         data: u32 in/u32 in_wire/u32 out/u32 out_wire
  70
  71         ziplinks commpression statistics