unbound/pythonmod/examples/resip.py

   1 '''
   2  resip.py: This example shows how to generate authoritative response
   3            and how to find out the IP address of a client
   4
   5  Copyright (c) 2009, Zdenek Vasicek (vasicek AT fit.vutbr.cz)
   6                      Marek Vavrusa  (xvavru00 AT stud.fit.vutbr.cz)
   7
   8  This software is open source.
   9
  10  Redistribution and use in source and binary forms, with or without
  11  modification, are permitted provided that the following conditions
  12  are met:
  13
  14     * Redistributions of source code must retain the above copyright notice,
  15       this list of conditions and the following disclaimer.
  16
  17     * Redistributions in binary form must reproduce the above copyright notice,
  18       this list of conditions and the following disclaimer in the documentation
  19       and/or other materials provided with the distribution.
  20
  21     * Neither the name of the organization nor the names of its
  22       contributors may be used to endorse or promote products derived from this
  23       software without specific prior written permission.
  24
  25  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  26  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  27  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  28  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE
  29  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  30  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  31  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  32  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  33  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  35  POSSIBILITY OF SUCH DAMAGE.
  36
  37
  38  Usage:
  39
  40    dig @127.0.0.1 -t TXT what.is.my.ip.
  41 '''
  42
  43 def init(id, cfg): return True
  44
  45 def deinit(id): return True
  46
  47 def inform_super(id, qstate, superqstate, qdata): return True
  48
  49 def operate(id, event, qstate, qdata):
  50     print "Operate", event,"state:",qstate
  51
  52     # Please note that if this module blocks, by moving to the validator
  53     # to validate or iterator to lookup or spawn a subquery to look up,
  54     # then, other incoming queries are queued up onto this module and
  55     # all of them receive the same reply.
  56     # You can inspect the cache.
  57
  58     if (event == MODULE_EVENT_NEW) or (event == MODULE_EVENT_PASS):
  59         if (qstate.qinfo.qname_str.endswith("what.is.my.ip.")): #query name ends with localdomain
  60             #create instance of DNS message (packet) with given parameters
  61             msg = DNSMessage(qstate.qinfo.qname_str, RR_TYPE_TXT, RR_CLASS_IN, PKT_QR | PKT_RA | PKT_AA)
  62             #append RR
  63             if (qstate.qinfo.qtype == RR_TYPE_TXT) or (qstate.qinfo.qtype == RR_TYPE_ANY):
  64                rl = qstate.mesh_info.reply_list
  65                while (rl):
  66                    if rl.query_reply:
  67                       q = rl.query_reply
  68                       # The TTL of 0 is mandatory, otherwise it ends up in
  69                       # the cache, and is returned to other IP addresses.
  70                       msg.answer.append("%s 0 IN TXT \"%s %d (%s)\"" % (qstate.qinfo.qname_str, q.addr,q.port,q.family))
  71                    rl = rl.next
  72
  73             #set qstate.return_msg
  74             if not msg.set_return_msg(qstate):
  75                 qstate.ext_state[id] = MODULE_ERROR
  76                 return True
  77
  78             #we don't need validation, result is valid
  79             qstate.return_msg.rep.security = 2
  80
  81             qstate.return_rcode = RCODE_NOERROR
  82             qstate.ext_state[id] = MODULE_FINISHED
  83             return True
  84         else:
  85             #pass the query to validator
  86             qstate.ext_state[id] = MODULE_WAIT_MODULE
  87             return True
  88
  89     if event == MODULE_EVENT_MODDONE:
  90         log_info("pythonmod: iterator module done")
  91         qstate.ext_state[id] = MODULE_FINISHED
  92         return True
  93
  94     log_err("pythonmod: bad event")
  95     qstate.ext_state[id] = MODULE_ERROR
  96     return True