From dfd03bb91cc87ca903e738c3b38949092f298e96 Mon Sep 17 00:00:00 2001
From: Andreas Granig <agranig@sipwise.com>
Date: Sun, 14 Oct 2007 14:14:59 +0000
Subject: [PATCH] Added two new plugins:   - click2dial: a c2d application with
 uac-auth support   - sw_prepaid_sip: the signalling part for a prepaid engine

git-svn-id: http://svn.berlios.de/svnroot/repos/sems/trunk@527 8eb893ce-cfd4-0310-b710-fb5ebe64c474
---
 apps/click2dial/Click2Dial.cpp              | 288 ++++++++++++++++++
 apps/click2dial/Click2Dial.h                |  90 ++++++
 apps/click2dial/Makefile                    |  10 +
 apps/click2dial/TODO                        |   4 +
 apps/click2dial/etc/click2dial.conf         |   2 +
 apps/click2dial/example.py                  |  35 +++
 apps/sw_prepaid_sip/Makefile                |   7 +
 apps/sw_prepaid_sip/SWPrepaidSIP.cpp        | 319 ++++++++++++++++++++
 apps/sw_prepaid_sip/SWPrepaidSIP.h          |  91 ++++++
 apps/sw_prepaid_sip/etc/sw_prepaid_sip.conf |   2 +
 doc/Readme.click2dial                       |  20 ++
 doc/Readme.sw_prepaid_sip                   | 176 +++++++++++
 12 files changed, 1044 insertions(+)
 create mode 100644 apps/click2dial/Click2Dial.cpp
 create mode 100644 apps/click2dial/Click2Dial.h
 create mode 100644 apps/click2dial/Makefile
 create mode 100644 apps/click2dial/TODO
 create mode 100644 apps/click2dial/etc/click2dial.conf
 create mode 100644 apps/click2dial/example.py
 create mode 100644 apps/sw_prepaid_sip/Makefile
 create mode 100644 apps/sw_prepaid_sip/SWPrepaidSIP.cpp
 create mode 100644 apps/sw_prepaid_sip/SWPrepaidSIP.h
 create mode 100644 apps/sw_prepaid_sip/etc/sw_prepaid_sip.conf
 create mode 100644 doc/Readme.click2dial
 create mode 100644 doc/Readme.sw_prepaid_sip

diff --git a/apps/click2dial/Click2Dial.cpp b/apps/click2dial/Click2Dial.cpp
new file mode 100644
index 00000000..48e37f43
--- /dev/null
+++ b/apps/click2dial/Click2Dial.cpp
@@ -0,0 +1,288 @@
+/*
+ * $Id: $
+ *
+ * Copyright (C) 2007 Sipwise GmbH
+ * Based on the concept of "announcement", Copyright (C) 2002-2003 Fhg Fokus
+ *
+ * This file is part of sems, a free SIP media server.
+ *
+ * sems is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * For a license to use the sems software under conditions
+ * other than those described here, or to purchase support for this
+ * software, please contact iptel.org by e-mail at the following addresses:
+ *    info@iptel.org
+ *
+ * sems is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "Click2Dial.h"
+#include "AmSessionContainer.h"
+#include "AmConfig.h"
+#include "AmUtils.h"
+#include "AmApi.h"
+#include "AmPlugIn.h"
+
+#include "AmMediaProcessor.h"
+
+#include "sems.h"
+#include "log.h"
+
+#define MOD_NAME "click2dial"
+
+EXPORT_SESSION_FACTORY(Click2DialFactory, MOD_NAME);
+
+string Click2DialFactory::AnnouncePath;
+string Click2DialFactory::AnnounceFile;
+
+Click2DialFactory::Click2DialFactory(const string& _app_name)
+: AmSessionFactory(_app_name)
+{
+}
+
+
+int Click2DialFactory::onLoad()
+{
+  AmConfigReader cfg;
+  if(cfg.loadFile(AmConfig::ModConfigPath + string(MOD_NAME ".conf")))
+    return -1;
+
+  // get application specific global parameters
+  configureModule(cfg);
+
+  AnnouncePath = cfg.getParameter("announce_path",ANNOUNCE_PATH);
+  if(!AnnouncePath.empty() && AnnouncePath[AnnouncePath.length()-1] != '/')
+    AnnouncePath += "/";
+
+  AnnounceFile = cfg.getParameter("default_announce",ANNOUNCE_FILE);
+  DBG("AnnounceFile = %s\n",AnnounceFile.c_str());
+
+  string announce_file = AnnouncePath + AnnounceFile;
+  if(!file_exists(announce_file)) {
+    ERROR("default file for ann_b2b module does not exist ('%s').\n",
+      announce_file.c_str());
+    return -1;
+  }
+
+  return 0;
+}
+
+
+string Click2DialFactory::getAnnounceFile(const AmSipRequest& req)
+{
+  string announce_path = AnnouncePath;
+  string announce_file = announce_path + req.domain
+    + "/" + req.user + ".wav";
+
+  DBG("trying '%s'\n",announce_file.c_str());
+  if(file_exists(announce_file))
+    goto end;
+
+  announce_file = announce_path + req.user + ".wav";
+  DBG("trying '%s'\n",announce_file.c_str());
+  if(file_exists(announce_file))
+    goto end;
+  announce_file = AnnouncePath + AnnounceFile;
+
+  end:
+  return announce_file;
+}
+
+
+AmSession* Click2DialFactory::onInvite(const AmSipRequest& req, AmArg& session_params)
+{
+  UACAuthCred* cred = NULL;
+  string callee_uri, a_realm, a_user, a_pwd;
+
+  if(session_params.size() != 4) {
+    ERROR("Need 4 parameters, got %d\n", session_params.size());
+    return NULL;
+  }
+
+  if(session_params.get(0).getType() == AmArg::CStr) {
+    a_realm = string(session_params.get(0).asCStr());
+  }
+  else {
+    ERROR("All arguments have to be CStr\n");
+    return NULL;
+  }
+  if(session_params.get(1).getType() == AmArg::CStr) {
+    a_user = string(session_params.get(1).asCStr());
+  }
+  else {
+    ERROR("All arguments have to be CStr\n");
+    return NULL;
+  }
+  if (session_params.get(2).getType() == AmArg::CStr) {
+    a_pwd = string(session_params.get(2).asCStr());
+  }
+  else {
+    ERROR("All arguments have to be CStr\n");
+    return NULL;
+  }
+
+  cred = new UACAuthCred(a_realm, a_user, a_pwd);
+  if(cred == NULL) {
+    ERROR("Failed to create authentication handle\n");
+    return NULL;
+  }
+
+  if (session_params.get(3).getType() == AmArg::CStr) {
+    callee_uri = string(session_params.get(3).asCStr());
+  }
+  else {
+    ERROR("All arguments have to be CStr\n");
+    return NULL;
+  }
+
+  AmSession* s = new C2DCallerDialog(req, getAnnounceFile(req), callee_uri, cred);
+  if(s == NULL) {
+    ERROR("Failed to create a click2dial dialog");
+    return NULL;
+  }
+
+  AmSessionEventHandlerFactory* uac_auth_f =
+    AmPlugIn::instance()->getFactory4Seh("uac_auth");
+  if(uac_auth_f != NULL) {
+    DBG("UAC Auth enabled for new announcement session.\n");
+    AmSessionEventHandler *h = uac_auth_f->getHandler(s);
+    if (h != NULL) {
+      s->addHandler(h);
+    }
+    else {
+      ERROR("Failed to get authentication event handler");
+      delete s;
+      return NULL;
+    }
+  }
+  else {
+    ERROR("uac_auth interface not accessible. "
+      "Load uac_auth for authenticated dialout.\n");
+
+    return NULL;
+  }
+
+  return s;
+}
+
+
+AmSession* Click2DialFactory::onInvite(const AmSipRequest& req)
+{
+  return new C2DCallerDialog(req, getAnnounceFile(req), NULL, NULL);
+}
+
+
+C2DCallerDialog::C2DCallerDialog(const AmSipRequest& req,
+const string& filename, const string& c_uri, UACAuthCred* credentials)
+: filename(filename), callee_uri(c_uri), cred(credentials),
+AmB2BCallerSession()
+{
+  sip_relay_only = false;
+}
+
+
+void C2DCallerDialog::onSessionStart(const AmSipReply& rep)
+{
+  setReceiving(false);
+  invite_req.body = rep.body;
+
+  if(wav_file.open(filename,AmAudioFile::Read))
+    throw string("AnnouncementDialog::onSessionStart: Cannot open file\n");
+  setOutput(&wav_file);
+}
+
+
+void C2DCallerDialog::onSessionStart(const AmSipRequest& req)
+{
+}
+
+
+void C2DCallerDialog::process(AmEvent* event)
+{
+  AmAudioEvent* audio_event = dynamic_cast<AmAudioEvent*>(event);
+  if(audio_event && audio_event->event_id == AmAudioEvent::cleared) {
+
+    if(getCalleeStatus() != None)
+      return;
+    AmMediaProcessor::instance()->removeSession(this);
+
+    connectCallee(string("<") + callee_uri + ">", callee_uri);
+    return;
+  }
+
+  AmB2BCallerSession::process(event);
+}
+
+
+void C2DCallerDialog::createCalleeSession()
+{
+  UACAuthCred* c = new UACAuthCred(cred.get()->realm,
+    cred.get()->user, cred.get()->pwd);
+
+  AmB2BCalleeSession* callee_session = new C2DCalleeDialog(this, c);
+  AmSipDialog& callee_dlg = callee_session->dlg;
+
+  other_id = AmSession::getNewId();
+
+  callee_dlg.local_tag    = other_id;
+  callee_dlg.callid       = AmSession::getNewId() + "@" + AmConfig::LocalIP;
+  callee_dlg.local_party  = dlg.local_party;
+  callee_dlg.remote_party = dlg.remote_party;
+  callee_dlg.remote_uri   = dlg.remote_uri;
+
+  callee_session->start();
+
+  AmSessionContainer* sess_cont = AmSessionContainer::instance();
+  sess_cont->addSession(other_id,callee_session);
+}
+
+
+void C2DCallerDialog::onB2BEvent(B2BEvent* ev)
+{
+  if(ev->event_id == B2BSipReply) {
+    AmSipReply& reply = ((B2BSipReplyEvent*)ev)->reply;
+
+    if(reply.code == 407 && cred.get() != NULL) {
+      AmB2BSession::onB2BEvent(ev);
+      return;
+    }
+  }
+  AmB2BCallerSession::onB2BEvent(ev);
+}
+
+
+C2DCalleeDialog::C2DCalleeDialog(const AmB2BCallerSession* caller, UACAuthCred* credentials)
+: AmB2BCalleeSession(caller), cred(credentials)
+{
+  setAuthHandler();
+}
+
+
+void C2DCalleeDialog::setAuthHandler()
+{
+  if(cred.get() != NULL) {
+    AmSessionEventHandlerFactory* uac_auth_f =
+      AmPlugIn::instance()->getFactory4Seh("uac_auth");
+    if (uac_auth_f != NULL) {
+      AmSessionEventHandler *h = uac_auth_f->getHandler(this);
+      if (h != NULL ) {
+        DBG("uac-auth enabled for new callee session.\n");
+        addHandler(h);
+      }
+      else {
+        ERROR("uac_auth interface not accessible. "
+          "Load uac_auth for authenticated dialout.\n");
+      }
+    }
+  }
+}
diff --git a/apps/click2dial/Click2Dial.h b/apps/click2dial/Click2Dial.h
new file mode 100644
index 00000000..dcb69fb4
--- /dev/null
+++ b/apps/click2dial/Click2Dial.h
@@ -0,0 +1,90 @@
+/*
+ * $Id: $
+ *
+ * Copyright (C) 2007 Sipwise GmbH
+ * Based on the concept of "announcement", Copyright (C) 2002-2003 Fhg Fokus
+ *
+ * This file is part of sems, a free SIP media server.
+ *
+ * sems is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * For a license to use the sems software under conditions
+ * other than those described here, or to purchase support for this
+ * software, please contact iptel.org by e-mail at the following addresses:
+ *    info@iptel.org
+ *
+ * sems is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _CLICK_2_DIAL_H_
+#define _CLICK_2_DIAL_H_
+
+#include "AmSession.h"
+#include "AmConfigReader.h"
+#include "AmSipRequest.h"
+#include "AmAudio.h"
+#include "AmB2BSession.h"
+
+#include "ampi/UACAuthAPI.h"
+
+#include <string>
+using std::string;
+
+class Click2DialFactory: public AmSessionFactory
+{
+  string getAnnounceFile(const AmSipRequest& req);
+
+  public:
+
+    static string AnnouncePath;
+    static string AnnounceFile;
+    static AmSessionEventHandler* AuthHandler;
+
+    Click2DialFactory(const string& _app_name);
+
+    int onLoad();
+    AmSession* onInvite(const AmSipRequest& req);
+    AmSession* onInvite(const AmSipRequest& req, AmArg& session_params);
+};
+
+class C2DCallerDialog: public AmB2BCallerSession, public CredentialHolder
+{
+  AmAudioFile wav_file;
+  string filename;
+  string callee_uri;
+  std::auto_ptr<UACAuthCred> cred;
+
+  public:
+
+    C2DCallerDialog(const AmSipRequest& req, const string& filename,
+      const string& callee_uri, UACAuthCred* credentials = NULL);
+
+    void process(AmEvent* event);
+    void onSessionStart(const AmSipRequest& req);
+    void onSessionStart(const AmSipReply& rep);
+    void createCalleeSession();
+    inline UACAuthCred* getCredentials() { return cred.get(); }
+    void onB2BEvent(B2BEvent*);
+};
+
+class C2DCalleeDialog : public AmB2BCalleeSession, public CredentialHolder
+{
+  std::auto_ptr<UACAuthCred> cred;
+  void setAuthHandler();
+
+  public:
+
+    C2DCalleeDialog(const AmB2BCallerSession* caller, UACAuthCred* credentials = NULL);
+    inline UACAuthCred* getCredentials() { return cred.get(); }
+};
+#endif                           // _CLICK_2_DIAL_H_
diff --git a/apps/click2dial/Makefile b/apps/click2dial/Makefile
new file mode 100644
index 00000000..b7ec3b26
--- /dev/null
+++ b/apps/click2dial/Makefile
@@ -0,0 +1,10 @@
+plug_in_name = click2dial
+
+module_ldflags =
+module_cflags  = 
+
+extra_install = $(plug_in_name)_audio
+
+COREPATH ?=../../core
+include $(COREPATH)/plug-in/Makefile.app_module
+
diff --git a/apps/click2dial/TODO b/apps/click2dial/TODO
new file mode 100644
index 00000000..75674474
--- /dev/null
+++ b/apps/click2dial/TODO
@@ -0,0 +1,4 @@
+2007-10-13 agranig:
+	Add a mechanism to kind of poll for the status
+	of the current call (e.g. to be used to visualize
+	the progress on a web site).
diff --git a/apps/click2dial/etc/click2dial.conf b/apps/click2dial/etc/click2dial.conf
new file mode 100644
index 00000000..56a38b99
--- /dev/null
+++ b/apps/click2dial/etc/click2dial.conf
@@ -0,0 +1,2 @@
+announce_path=/usr/local/lib/sems/audio/
+default_announce=default_en.wav
diff --git a/apps/click2dial/example.py b/apps/click2dial/example.py
new file mode 100644
index 00000000..8548d463
--- /dev/null
+++ b/apps/click2dial/example.py
@@ -0,0 +1,35 @@
+#!/usr/bin/python
+
+########################################################################
+# An example using python to initiate a call via di_dialer and xmlrpc2di
+#
+# In this case, the R-Uris of leg (a) and leg(b) are looking like
+# sip:user@proxy-ip;sw_domain=domain to route the call
+# via an outbound proxy "proxy". The proxy in question has to
+# extract the value of sw_domain and place it into the domain
+# of the R-Uri to correctly route it to the destination.
+########################################################################
+
+proxy = "192.168.100.10"
+xmlrpc_url = "http://127.0.0.1:8090"
+
+caller_user = "foo"
+caller_domain = "iptel.org"
+callee_user = "bar"
+callee_domain = "iptel.org"
+
+auth_user = "foo"
+auth_pass = "foopass"
+auth_realm = "iptel.org"
+
+announce_file = "default_en"
+
+from xmlrpclib import *
+s = ServerProxy(xmlrpc_url)
+s.dial_auth_b2b(
+        "click2dial", announce_file, 
+        "sip:" + caller_user + "@" + caller_domain, 
+        "sip:" + callee_user + "@" + callee_domain, 
+        "sip:" + caller_user + "@" + proxy + ";sw_domain=" + caller_domain,
+        "sip:" + callee_user + "@" + proxy + ";sw_domain=" + callee_domain,
+        auth_realm, auth_user, auth_pass)
diff --git a/apps/sw_prepaid_sip/Makefile b/apps/sw_prepaid_sip/Makefile
new file mode 100644
index 00000000..1aff8add
--- /dev/null
+++ b/apps/sw_prepaid_sip/Makefile
@@ -0,0 +1,7 @@
+plug_in_name = sw_prepaid_sip
+
+module_ldflags =
+module_cflags  = 
+
+COREPATH ?= ../../core
+include $(COREPATH)/plug-in/Makefile.app_module
diff --git a/apps/sw_prepaid_sip/SWPrepaidSIP.cpp b/apps/sw_prepaid_sip/SWPrepaidSIP.cpp
new file mode 100644
index 00000000..3b77c1d5
--- /dev/null
+++ b/apps/sw_prepaid_sip/SWPrepaidSIP.cpp
@@ -0,0 +1,319 @@
+/*
+ * $Id: $
+ *
+ * Copyright (C) 2007 Sipwise GmbH
+ * Based on the concept of mycc, Copyright (C) 2002-2003 Fhg Fokus
+ *
+ * This file is part of sems, a free SIP media server.
+ *
+ * sems is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * For a license to use the sems software under conditions
+ * other than those described here, or to purchase support for this
+ * software, please contact iptel.org by e-mail at the following addresses:
+ *    info@iptel.org
+ *
+ * sems is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "SWPrepaidSIP.h"
+
+#include "log.h"
+#include "AmUtils.h"
+#include "AmAudio.h"
+#include "AmPlugIn.h"
+#include "AmMediaProcessor.h"
+#include "AmSipDialog.h"
+#include "AmConfigReader.h"
+
+#include <sys/time.h>
+#include <time.h>
+
+#define MOD_NAME "sw_prepaid_sip"
+
+#define TIMERID_CREDIT_TIMEOUT 1
+#define ACC_PLUGIN "sw_prepaid_acc"
+
+EXPORT_SESSION_FACTORY(SWPrepaidSIPFactory,MOD_NAME);
+
+SWPrepaidSIPFactory::SWPrepaidSIPFactory(const string& _app_name)
+: AmSessionFactory(_app_name), user_timer_fact(NULL)
+{
+}
+
+
+int SWPrepaidSIPFactory::onLoad()
+{
+  AmConfigReader cfg;
+  if(cfg.loadFile(AmConfig::ModConfigPath + string(MOD_NAME ".conf")))
+    return -1;
+
+  string acc_plugin = cfg.getParameter("acc_plugin", ACC_PLUGIN);
+
+  user_timer_fact = AmPlugIn::instance()->getFactory4Di("user_timer");
+  if(!user_timer_fact) {
+    ERROR("could not load user_timer from session_timer plug-in\n");
+    return -1;
+  }
+
+  DBG("use acc plugin '%s'", acc_plugin.c_str());
+  cc_acc_fact = AmPlugIn::instance()->getFactory4Di(acc_plugin);
+  if(!cc_acc_fact) {
+    ERROR("could not load accounting plugin '%s', please provide a valid module name\n",
+      acc_plugin.c_str());
+    return -1;
+  }
+
+  return 0;
+}
+
+
+AmSession* SWPrepaidSIPFactory::onInvite(const AmSipRequest& req)
+{
+  AmDynInvoke* user_timer = user_timer_fact->getInstance();
+  if(!user_timer) {
+    ERROR("could not get a user timer reference\n");
+    throw AmSession::Exception(500,"could not get a user timer reference");
+  }
+
+  AmDynInvoke* cc_acc = cc_acc_fact->getInstance();
+  if(!cc_acc) {
+    ERROR("could not get an accounting reference\n");
+    throw AmSession::Exception(500,"could not get an acc reference");
+  }
+
+  return new SWPrepaidSIPDialog(cc_acc, user_timer);
+}
+
+
+SWPrepaidSIPDialog::SWPrepaidSIPDialog(AmDynInvoke* cc_acc, AmDynInvoke* user_timer)
+: m_state(CC_Init),
+m_cc_acc(cc_acc), m_user_timer(user_timer),
+AmB2BCallerSession()
+
+{
+  sip_relay_only = false;
+  memset(&m_acc_start, 0, sizeof(struct timeval));
+}
+
+
+SWPrepaidSIPDialog::~SWPrepaidSIPDialog()
+{
+}
+
+
+void SWPrepaidSIPDialog::onInvite(const AmSipRequest& req)
+{
+  // TODO: do reinvites get here? if so, don't set a timer then
+
+  // TODO: errors thrown as exception don't seem to trigger a reply?
+
+  setReceiving(false);
+  AmMediaProcessor::instance()->removeSession(this);
+
+  m_uuid = getHeader(req.hdrs,"P-Caller-Uuid");
+  if(!m_uuid.length()) {
+    ERROR("Application header P-Caller-Uuid not found\n");
+    throw AmSession::Exception(500, "could not get UUID parameter");
+  }
+
+  m_proxy = getHeader(req.hdrs,"P-Proxy");
+  if(!m_proxy.length()) {
+    ERROR("Application header P-Proxy not found\n");
+    throw AmSession::Exception(500, "could not get PROXY parameter");
+  }
+
+  m_ruri = getHeader(req.hdrs,"P-R-Uri");
+  if(!m_ruri.length()) {
+    ERROR("Application header P-R-Uri not found\n");
+    throw AmSession::Exception(500, "could not get RURI parameter");
+  }
+
+  m_dest = getHeader(req.hdrs,"P-Acc-Dest");
+
+  if(!m_dest.length()) {
+    ERROR("Application header P-Acc-Dest not found\n");
+    throw AmSession::Exception(500, "could not get destination pattern parameter");
+  }
+
+  DBG("UUID '%s' and pattern '%s' prepared for prepaid processing\n", m_uuid.c_str(), m_dest.c_str());
+
+  m_starttime = time(NULL);
+  m_localreq = req;
+
+  AmArg di_args,ret;
+  di_args.push(m_uuid.c_str());
+  di_args.push((int)m_starttime);
+  di_args.push(m_dest.c_str());
+  m_cc_acc->invoke("getCredit", di_args, ret);
+  m_credit = ret.get(0).asInt();
+
+  if(m_credit == -1) {
+    ERROR("Failed to fetch credit from accounting module\n");
+    if(dlg.reply(req, 500, "Failed to fetch credit") != 0) {
+      throw AmSession::Exception(500,"Failed to fetch credit");
+    }
+    return;
+  }
+  else if(m_credit == 0) {
+    DBG("No credit left\n");
+    m_state = CC_Teardown;
+    if(dlg.reply(req, 402, "Unsufficient Credit") != 0) {
+      throw AmSession::Exception(500,"Failed to reply 402");
+    }
+    setStopped();
+    //throw AmSession::Exception(402, "Unsufficient Credit");
+  }
+  else {
+    DBG("Credit for UUID %s is %d seconds, calling %s now\n", m_uuid.c_str(), m_credit, req.r_uri.c_str());
+    m_state = CC_Dialing;
+
+    if(dlg.reply(req, 101, "Connecting") != 0) {
+      throw AmSession::Exception(500,"Failed to reply 101");
+    }
+
+    invite_req = req;
+    dlg.updateStatus(req);
+    recvd_req.insert(make_pair(req.cseq,req));
+
+    connectCallee("<" + m_ruri + ">", m_proxy + ";sw_prepaid", true);
+    sip_relay_only = true;
+  }
+}
+
+
+void SWPrepaidSIPDialog::process(AmEvent* ev)
+{
+  AmAudioEvent* audio_ev = dynamic_cast<AmAudioEvent*>(ev);
+  if(audio_ev && (audio_ev->event_id == AmAudioEvent::noAudio) && m_state == CC_Teardown) {
+    DBG("SWPrepaidSIPDialog::process: Playlist is empty!\n");
+    terminateLeg();
+
+    ev->processed = true;
+    return;
+  }
+
+  AmPluginEvent* plugin_event = dynamic_cast<AmPluginEvent*>(ev);
+  if(plugin_event && plugin_event->name == "timer_timeout") {
+    int timer_id = plugin_event->data.get(0).asInt();
+    if (timer_id == TIMERID_CREDIT_TIMEOUT) {
+      DBG("timer timeout, no more credit\n");
+      stopAccounting();
+      terminateOtherLeg();
+      terminateLeg();
+
+      ev->processed = true;
+      return;
+    }
+  }
+
+  AmB2BCallerSession::process(ev);
+}
+
+
+bool SWPrepaidSIPDialog::onOtherReply(const AmSipReply& reply)
+{
+  bool ret = false;
+
+  if (m_state == CC_Dialing) {
+    if (reply.code < 200) {
+      DBG("Callee is trying... code %d\n", reply.code);
+    }
+    else if(reply.code < 300) {
+      if(getCalleeStatus()  == Connected) {
+        m_state = CC_Connected;
+        startAccounting();
+        setInOut(NULL, NULL);
+
+        // set the call timer
+        AmArg di_args,ret;
+        di_args.push(TIMERID_CREDIT_TIMEOUT);
+        di_args.push(m_credit);  // in seconds
+        di_args.push(dlg.local_tag.c_str());
+        m_user_timer->invoke("setTimer", di_args, ret);
+      }
+    }
+    else if(reply.code == 487 && dlg.getStatus() == AmSipDialog::Pending) {
+      DBG("Canceling leg A on 487 from B");
+      dlg.reply(m_localreq, 487, "Call terminated");
+      setStopped();
+      ret = true;
+    }
+    else if (reply.code >= 300 && dlg.getStatus() == AmSipDialog::Connected) {
+      DBG("Callee final error in connected state with code %d\n",reply.code);
+      terminateLeg();
+    }
+    else {
+      DBG("Callee final error with code %d\n",reply.code);
+      AmB2BCallerSession::onOtherReply(reply);
+    }
+  }
+  return ret;
+}
+
+
+void SWPrepaidSIPDialog::onOtherBye(const AmSipRequest& req)
+{
+  stopAccounting();
+  AmB2BCallerSession::onOtherBye(req);
+}
+
+
+void SWPrepaidSIPDialog::onBye(const AmSipRequest& req)
+{
+  if (m_state == CC_Connected) {
+    stopAccounting();
+  }
+  terminateOtherLeg();
+  setStopped();
+}
+
+
+void SWPrepaidSIPDialog::onCancel()
+{
+  if(dlg.getStatus() == AmSipDialog::Pending) {
+    DBG("Wait for leg B to terminate");
+  }
+  else {
+    DBG("Canceling leg A on CANCEL since dialog is not pending");
+    dlg.reply(m_localreq, 487, "Call terminated");
+    setStopped();
+  }
+}
+
+
+void SWPrepaidSIPDialog::startAccounting()
+{
+  gettimeofday(&m_acc_start, NULL);
+  DBG("start accounting at %ld\n", m_acc_start.tv_sec);
+}
+
+
+void SWPrepaidSIPDialog::stopAccounting()
+{
+  if(m_acc_start.tv_sec != 0 || m_acc_start.tv_usec != 0) {
+    struct timeval now;
+    gettimeofday(&now, NULL);
+    timersub(&now, &m_acc_start, &now);
+    if(now.tv_usec > 500000)
+      now.tv_sec++;
+    DBG("Call lasted %ld seconds\n", now.tv_sec);
+
+    AmArg di_args,ret;
+    di_args.push(m_uuid.c_str());
+    di_args.push((int)m_starttime);
+    di_args.push((int)now.tv_sec);
+    di_args.push(m_dest.c_str());
+    m_cc_acc->invoke("subtractCredit", di_args, ret);
+  }
+}
diff --git a/apps/sw_prepaid_sip/SWPrepaidSIP.h b/apps/sw_prepaid_sip/SWPrepaidSIP.h
new file mode 100644
index 00000000..919693b8
--- /dev/null
+++ b/apps/sw_prepaid_sip/SWPrepaidSIP.h
@@ -0,0 +1,91 @@
+/*
+ * $Id: $
+ *
+ * Copyright (C) 2007 Sipwise GmbH
+ * Based on the concept of mycc, Copyright (C) 2002-2003 Fhg Fokus
+ *
+ * This file is part of sems, a free SIP media server.
+ *
+ * sems is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * For a license to use the sems software under conditions
+ * other than those described here, or to purchase support for this
+ * software, please contact iptel.org by e-mail at the following addresses:
+ *    info@iptel.org
+ *
+ * sems is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _SW_PREPAID_SIP_H
+#define _SW_PREPAID_SIP_H
+
+#include "AmB2BSession.h"
+
+#include <time.h>
+#include <string>
+using std::string;
+
+class SWPrepaidSIPFactory: public AmSessionFactory
+{
+  AmDynInvokeFactory* user_timer_fact;
+  AmDynInvokeFactory* cc_acc_fact;
+
+  public:
+    SWPrepaidSIPFactory(const string& _app_name);
+
+    int onLoad();
+    AmSession* onInvite(const AmSipRequest& req);
+};
+
+class SWPrepaidSIPDialog : public AmB2BCallerSession
+{
+  enum {
+    CC_Init = 0,
+    CC_Dialing,
+    CC_Connected,
+    CC_Teardown
+  } CallerState;
+
+  int m_state;
+  AmSipRequest m_localreq;
+
+  string m_uuid;
+  string m_ruri;
+  string m_proxy;
+  string m_dest;
+  time_t m_starttime;
+  int m_credit;
+
+  void startAccounting();
+  void stopAccounting();
+  struct timeval m_acc_start;
+
+  AmDynInvoke* m_user_timer;
+  AmDynInvoke* m_cc_acc;
+
+  public:
+
+    SWPrepaidSIPDialog(AmDynInvoke* cc_acc, AmDynInvoke* user_timer);
+    ~SWPrepaidSIPDialog();
+
+    void process(AmEvent* ev);
+    void onBye(const AmSipRequest& req);
+    void onInvite(const AmSipRequest& req);
+    void onCancel();
+
+  protected:
+
+    bool onOtherReply(const AmSipReply& reply);
+    void onOtherBye(const AmSipRequest& req);
+};
+#endif                           // _SW_PREPAID_SIP_H
diff --git a/apps/sw_prepaid_sip/etc/sw_prepaid_sip.conf b/apps/sw_prepaid_sip/etc/sw_prepaid_sip.conf
new file mode 100644
index 00000000..2bd1ab1f
--- /dev/null
+++ b/apps/sw_prepaid_sip/etc/sw_prepaid_sip.conf
@@ -0,0 +1,2 @@
+# the plugin to be used as accounting backend:
+acc_plugin = cc_acc
diff --git a/doc/Readme.click2dial b/doc/Readme.click2dial
new file mode 100644
index 00000000..ea60a45e
--- /dev/null
+++ b/doc/Readme.click2dial
@@ -0,0 +1,20 @@
+#######################################################################
+#
+# click2dial, an xmlrpc-enabled way to initiate authenticated calls
+# Copyright (C) 2007 Sipwise GmbH
+# Based on "announcement", Copyright (C) 2002-2003 Fhg Fokus
+#
+# Author: Andreas Granig <agranig@sipwise.com>
+#
+########################################################################
+
+How click2dial works
+------------------------
+
+Simply issue an xmlrpc request as shown in apps/click2dial/example.py
+to initiate an authenticated call.
+
+First, call leg (a) is connected, and an announcemnet defined in
+click2dial.conf is played. Then call leg (b) is contacted, and on success
+the two call legs are connected.
+
diff --git a/doc/Readme.sw_prepaid_sip b/doc/Readme.sw_prepaid_sip
new file mode 100644
index 00000000..833d01e5
--- /dev/null
+++ b/doc/Readme.sw_prepaid_sip
@@ -0,0 +1,176 @@
+#######################################################################
+#
+# sw_prepaid_sip, the signalling-only prepaid engine
+# Copyright (C) 2007 Sipwise GmbH
+# Based on mycc, Copyright (C) 2002-2003 Fhg Fokus
+#
+# Author: Andreas Granig <agranig@sipwise.com>
+#
+########################################################################
+
+How sw_prepaid_sip works
+------------------------
+
+The plugin extracts the headers "P-Caller-Uuid" and "P-Acc-Dest" as
+caller and callee identifiers, respectively. Using these values,
+it calls an accounting backend, which can defined in sw_prepaid_sip.conf,
+and fetches the maximum call duration (per default, cc_acc is used as
+billing backend, which is just a dummy plugin to show the most basic
+concept of a billing backend).
+
+If the credit is > 0, it uses the Request-Uri passed in the header "P-R-Uri"
+and connects the callee using the outbound proxy passed in the header "P-Proxy".
+
+When the call duration exceeds the credit, the call is terminated by SEMS.
+
+
+A typical call flow would look like this, where (a) is the caller leg and
+(b) the callee leg:
+
+Caller    Proxy       SEMS      Callee
+  |          |          |          |
+  |  INV(a)  |          |          |
+  |--------->|          |          |
+  |  407(a)  |          |          |
+  |<---------|          |          |
+  |  INV(a)  |          |          |
+  |--------->|          |          |
+  |  100(a)  |          |          |
+  |<---------|          |          |
+  |          |  INV(a)  |          |
+  |          |--------->|          |
+  |          |  101(a)  |          |
+  |          |<---------|          |
+  |          |  INV(b)  |          |
+  |          |<---------|          |
+  |          |  INV(b)  |          |
+  |          |-------------------->|
+  |          |          |  180(b)  |
+  |          |<--------------------|
+  |          |  180(b)  |          |
+  |          |--------->|          |
+  |          |  180(a)  |          |
+  |          |<---------|          |
+  |  180(a)  |          |          |
+  |<---------|          |          |
+  |          |          |  200(b)  |
+  |          |<--------------------|
+  |          |  200(b)  |          |
+  |          |--------->|          |
+  |          |  200(a)  |          |
+  |          |<---------|          |
+  |  200(a)  |          |          |
+  |<---------|          |          |
+  |  ACK(a)  |          |          |
+  |--------->|          |          |
+  |          |  ACK(a)  |          |
+  |          |--------->|          |
+  |          |  ACK(b)  |          |
+  |          |<---------|          |
+  |          |  ACK(b)  |          |
+  |          |-------------------->|
+  |          |          |          |
+  |          |          |          |
+
+
+How to configure SEMS' sip proxy
+--------------------------------
+
+Modify the "tw_append" parameter of the "tm" option to pass the mandatory headers to
+SEMS:
+
+modparam("tm", "tw_append", 
+  "prepaid_headers:hdr[P-Caller-Uuid];hdr[P-Proxy];hdr[P-R-Uri];hdr[P-Acc-Dest]")
+
+Then add a proper block to pass prepaid calls to SEMS. In this example,
+we assume that calls prefixed by "pre" are considered prepaid requests.
+For ser-0.9.6 as SEMS' sip proxy, use something like:
+
+if(uri =~ "sip:pre.+@")
+{
+	strip(3);
+	if(!t_write_unix("/tmp/sems.sock","sw_prepaid_sip/prepaid_headers"))
+	{
+		xlog("L_ERR", "Error contacting SEMS - M=%rm R=%ru F=%fu T=%tu ID=%ci\n");
+		t_reply("500","Could not contact B2BUA server");
+	}
+	break;
+}
+
+If you need to pass other headers from leg (a) to leg (b), you can add them to "tw_append" 
+and they are copied to the other leg. This is for example necessary to pass the destination
+URI to leg (b), which can then be extracted from the proxy and set accordingly.
+
+How to configure a proxy to interact with sw_prepaid_sip
+--------------------------------------------------------
+
+If your proxy runs on IP 192.168.100.10:5060 and your SEMS' proxy on 192.168.100.10:5070, you
+can pass leg (a) to the prepaid engine like this (assuming you use OpenSER >= 1.2.0 as 
+sip proxy):
+
+if(/* caller is prepaid */)
+{
+	/* use authentication user as caller uuid in prepaid engine */
+	append_hf("P-Caller-Uuid: $au\r\n");
+
+	/* use simplified R-URI as destination pattern in prepaid engine;
+	   NOTE that cc_acc doesn't evaluate this field, but more 
+	   advanced backends might do, so sw_prepaid_sip requires
+	   this header */
+	append_hf("P-Acc-Dest: $rU@$rd\r\n");
+
+	/* the URI which is to be used by SEMS as outbound proxy for
+	   call leg (b) - use our own here */
+	append_hf("P-Proxy: sip:192.168.100.10:5060\r\n");
+
+	/* the R-URI to be used to connect call leg (b) */
+	append_hf("P-R-Uri: $ru\r\n");
+
+	if($du != null)
+	{
+		/* if there's a D-Uri set, also send it to SEMS to correctly contact
+		   call leg (b). NOTE you have to add this header in SEMS's sip proxy
+		   config as "tw_append" value. */
+		append_hf("P-D-Uri: $du\r\n");
+	}
+
+	/* point the R-Uri to SEMS' proxy and relay; this is just the most simple
+	   example, but you can also use the LCR module for SEMS load balancing
+	   and failover. */
+	rewriteuri("sip:192.168.100.10:5070");
+	t_relay();
+}
+
+In the above block, call leg (a) is passed to SEMS. Now we prepare a block to catch 
+call leg (b) coming from SEMS. Add this at the very beginning of your proxy configuration.
+
+/* usual sanity checks like msg-size and max-fwd, then do something like: */
+
+if(src_ip == 192.168.100.10 && src_port == 5070 /* check if from SEMS */
+	&& uri =~ ";sw_prepaid" /* this uri param is added by SEMS to detect prepaid calls */
+	&& method == "INVITE" && !has_totag()) /* only process initial invites here */
+{
+	/* recover the R-Uri (maybe check for existence first!) */
+	$ru = $hdr(P-R-Uri);
+
+	/* recover destination Uri */
+	if(is_present_hf("P-D-Uri"))
+	{
+		$du = $hdr(P-D-Uri);
+		insert_hf("Route: <$hdr(P-D-Uri)>\r\n");
+	}
+
+	/* you might also consider removing the helper headers
+	   by calling remove_hf(...) */
+
+	/* relay to callee */
+	t_relay();
+}
+
+Please note that the above example is a very basic one. For example, if you want to route
+to PSTN gateways, you might want to add an informational header in leg (a) and evaluate
+it in leg (b) to load a set of PSTN gateways instead of relaying to the R-Uri.
+
+IMPORTANT: make sure to prevent black-hats from spoofing the SEMS proxy address to place
+unauthenticated calls by using a private address for SEMS' sip proxy and by adding 
+proper firewall rules on your ingress router.