libnatpmpmodule.c

/* $Id: libnatpmpmodule.c,v 1.7 2012/03/05 19:38:37 nanard Exp $ */
/* libnatpmp
 * http://miniupnp.free.fr/libnatpmp.html
Copyright (c) 2007-2011, Thomas BERNARD
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright notice,
      this list of conditions and the following disclaimer in the documentation
      and/or other materials provided with the distribution.
    * The name of the author may not be used to endorse or promote products
	  derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
*/
#include <Python.h>
#ifdef _WIN32
#include <winsock2.h>
#else
#include <netinet/in.h>
#include <arpa/inet.h>
#endif

#define NATPMP_STATICLIB
#include "structmember.h"
#include "natpmp.h"

/* for compatibility with Python < 2.4 */
#ifndef Py_RETURN_NONE
#define Py_RETURN_NONE return Py_INCREF(Py_None), Py_None
#endif

#ifndef Py_RETURN_TRUE
#define Py_RETURN_TRUE return Py_INCREF(Py_True), Py_True
#endif

#ifndef Py_RETURN_FALSE
#define Py_RETURN_FALSE return Py_INCREF(Py_False), Py_False
#endif

typedef struct {
  PyObject_HEAD

  /* Type-specific fields go here. */
  unsigned int discoverdelay;

  natpmp_t natpmp;
} NATPMPObject;

static PyMemberDef NATPMP_members[] = {
  {"discoverdelay", T_UINT, offsetof(NATPMPObject, discoverdelay),
   0/*READWRITE*/, "value in ms used to wait for NATPMP responses"
  },
  {NULL}
};

static PyObject *
NATPMPObject_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
  NATPMPObject *self;

  self = (NATPMPObject *)type->tp_alloc(type, 0);
  if (self) {
    initnatpmp(&self->natpmp, 0, 0);
  }

  return (PyObject *)self;
}

static void
NATPMPObject_dealloc(NATPMPObject *self)
{
  closenatpmp(&self->natpmp);
  Py_TYPE(self)->tp_free((PyObject*)self);
}

static PyObject *
NATPMP_externalipaddress(NATPMPObject *self)
{
  int r;
  struct timeval timeout;
  fd_set fds;
  natpmpresp_t response;

  r = sendpublicaddressrequest(&self->natpmp);

  if (r < 0) {
#ifdef ENABLE_STRNATPMPERR
    PyErr_SetString(PyExc_Exception, strnatpmperr(r));
#endif
    return NULL;
  }

  do {
    FD_ZERO(&fds);
    FD_SET(self->natpmp.s, &fds);
    getnatpmprequesttimeout(&self->natpmp, &timeout);
    select(FD_SETSIZE, &fds, NULL, NULL, &timeout);
    r = readnatpmpresponseorretry(&self->natpmp, &response);
    if (r < 0 && r != NATPMP_TRYAGAIN) {
#ifdef ENABLE_STRNATPMPERR
      PyErr_SetString(PyExc_Exception, strnatpmperr(r));
#endif
      return NULL;
    }
  } while (r == NATPMP_TRYAGAIN);

  return Py_BuildValue("s", inet_ntoa(response.pnu.publicaddress.addr));
}

static PyObject *
NATPMP_domapping(natpmp_t *n, unsigned short eport, unsigned short iport,
		 const char *protocol, unsigned int lifetime)
{
  int proto;
  struct timeval timeout;
  fd_set fds;
  natpmpresp_t response;
  int r;

  if (!strncasecmp("tcp", protocol, 3)) {
    proto = NATPMP_PROTOCOL_TCP;
  } else if (!strncasecmp("udp", protocol, 3)) {
    proto = NATPMP_PROTOCOL_UDP;
  } else {
    PyErr_SetString(PyExc_Exception, "Unknown protocol");
    return NULL;
  }

  r = sendnewportmappingrequest(n, proto, iport, eport,
				lifetime);

  if (r < 0) {
#ifdef ENABLE_STRNATPMPERR
    PyErr_SetString(PyExc_Exception, strnatpmperr(r));
#endif
    return NULL;
  }

  do {
    FD_ZERO(&fds);
    FD_SET(n->s, &fds);
    getnatpmprequesttimeout(n, &timeout);
    select(FD_SETSIZE, &fds, NULL, NULL, &timeout);
    r = readnatpmpresponseorretry(n, &response);
    if (r < 0 && r != NATPMP_TRYAGAIN) {
#ifdef ENABLE_STRNATPMPERR
      PyErr_SetString(PyExc_Exception, strnatpmperr(r));
#endif
      return NULL;
    }
  } while (r == NATPMP_TRYAGAIN);

  return Py_BuildValue("H", response.pnu.newportmapping.mappedpublicport);
}


/* AddPortMapping(externalPort, protocol, internalPort, lifetime)
 * protocol is 'UDP' or 'TCP' */
static PyObject *
NATPMP_addportmapping(NATPMPObject *self, PyObject *args)
{
  unsigned short eport;
  unsigned short iport;
  unsigned int lifetime;
  const char *protocol;

  if (!PyArg_ParseTuple(args, "HsHI", &eport, &protocol, &iport, &lifetime))
    return NULL;

  return NATPMP_domapping(&self->natpmp, eport, iport, protocol, lifetime);
}

/* DeletePortMapping(externalPort, protocol, internalPort)
 * protocol is 'UDP' or 'TCP' */
static PyObject *
NATPMP_deleteportmapping(NATPMPObject *self, PyObject *args)
{
  unsigned short eport;
  unsigned short iport;
  const char *protocol;

  if (!PyArg_ParseTuple(args, "HsH", &eport, &protocol, &iport))
    return NULL;

  return NATPMP_domapping(&self->natpmp, eport, iport, protocol, 0);
}

/* natpmp.NATPMP object Method Table */
static PyMethodDef NATPMP_methods[] = {
  {"externalipaddress", (PyCFunction)NATPMP_externalipaddress, METH_NOARGS,
   "return external IP address"
  },
  {"addportmapping", (PyCFunction)NATPMP_addportmapping, METH_VARARGS,
   "add a port mapping"
  },
  {"deleteportmapping", (PyCFunction)NATPMP_deleteportmapping, METH_VARARGS,
   "delete a port mapping"
  },
  {NULL}  /* Sentinel */
};

static PyTypeObject NATPMPType = {
  PyObject_HEAD_INIT(NULL)
  0,					/*ob_size*/
  "libnatpmp.NATPMP",			/*tp_name*/
  sizeof(NATPMPObject),			/*tp_basicsize*/
  0,					/*tp_itemsize*/
  (destructor)NATPMPObject_dealloc,	/*tp_dealloc*/
  0,					/*tp_print*/
  0,					/*tp_getattr*/
  0,					/*tp_setattr*/
  0,					/*tp_compare*/
  0,					/*tp_repr*/
  0,					/*tp_as_number*/
  0,					/*tp_as_sequence*/
  0,					/*tp_as_mapping*/
  0,					/*tp_hash */
  0,					/*tp_call*/
  0,					/*tp_str*/
  0,					/*tp_getattro*/
  0,					/*tp_setattro*/
  0,					/*tp_as_buffer*/
  Py_TPFLAGS_DEFAULT,			/*tp_flags*/
  "NATPMP objects",			/* tp_doc */
  0,					/* tp_traverse */
  0,					/* tp_clear */
  0,					/* tp_richcompare */
  0,					/* tp_weaklistoffset */
  0,					/* tp_iter */
  0,					/* tp_iternext */
  NATPMP_methods,			/* tp_methods */
  NATPMP_members,			/* tp_members */
  0,					/* tp_getset */
  0,					/* tp_base */
  0,					/* tp_dict */
  0,					/* tp_descr_get */
  0,					/* tp_descr_set */
  0,					/* tp_dictoffset */
  0,					/* tp_init */
  0,					/* tp_alloc */
  NATPMPObject_new,			/* tp_new */
};

/* module methods */
static PyMethodDef libnatpmp_methods[] = {
    {NULL}  /* Sentinel */
};

#ifndef PyMODINIT_FUNC	/* declarations for DLL import/export */
#define PyMODINIT_FUNC void
#endif
PyMODINIT_FUNC
initlibnatpmp(void)
{
  PyObject* m;

  if (PyType_Ready(&NATPMPType) < 0)
    return;

  m = Py_InitModule3("libnatpmp", libnatpmp_methods,
		     "libnatpmp module.");

  Py_INCREF(&NATPMPType);
  PyModule_AddObject(m, "NATPMP", (PyObject *)&NATPMPType);
}