unbound/pythonmod/pythonmod.c

   1 /*
   2  * pythonmod.c: unbound module C wrapper
   3  *
   4  * Copyright (c) 2009, Zdenek Vasicek (vasicek AT fit.vutbr.cz)
   5  *                     Marek Vavrusa  (xvavru00 AT stud.fit.vutbr.cz)
   6  *
   7  * This software is open source.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  *    * Redistributions of source code must retain the above copyright notice,
  14  *      this list of conditions and the following disclaimer.
  15  *
  16  *    * Redistributions in binary form must reproduce the above copyright notice,
  17  *      this list of conditions and the following disclaimer in the documentation
  18  *      and/or other materials provided with the distribution.
  19  *
  20  *    * Neither the name of the organization nor the names of its
  21  *      contributors may be used to endorse or promote products derived from this
  22  *      software without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  25  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  26  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  27  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE
  28  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  34  * POSSIBILITY OF SUCH DAMAGE.
  35  */
  36 /**
  37  * \file
  38  * Python module for unbound.  Calls python script.
  39  */
  40
  41 /* ignore the varargs unused warning from SWIGs internal vararg support */
  42 #ifdef __GNUC__
  43 #pragma GCC diagnostic ignored "-Wunused-parameter"
  44 #pragma GCC diagnostic ignored "-Wunused-but-set-variable"
  45 #endif
  46
  47 #include "config.h"
  48 #include "ldns/sbuffer.h"
  49
  50 #undef _POSIX_C_SOURCE
  51 #undef _XOPEN_SOURCE
  52 #include <Python.h>
  53
  54 #include "pythonmod/pythonmod.h"
  55 #include "util/module.h"
  56 #include "util/config_file.h"
  57 #include "pythonmod_utils.h"
  58
  59 #ifdef S_SPLINT_S
  60 typedef struct PyObject PyObject;
  61 typedef struct PyThreadState PyThreadState;
  62 typedef void* PyGILState_STATE;
  63 #endif
  64
  65 /**
  66  * Global state for the module.
  67  */
  68 struct pythonmod_env {
  69
  70         /** Python script filename. */
  71         const char* fname;
  72
  73         /** Python main thread */
  74         PyThreadState* mainthr;
  75         /** Python module. */
  76         PyObject* module;
  77
  78         /** Module init function */
  79         PyObject* func_init;
  80         /** Module deinit function */
  81         PyObject* func_deinit;
  82         /** Module operate function */
  83         PyObject* func_operate;
  84         /** Module super_inform function */
  85         PyObject* func_inform;
  86
  87         /** Python dictionary. */
  88         PyObject* dict;
  89
  90         /** Module data. */
  91         PyObject* data;
  92
  93         /** Module qstate. */
  94         struct module_qstate* qstate;
  95 };
  96
  97 /**
  98  * Per query state for the iterator module.
  99  */
 100 struct pythonmod_qstate {
 101
 102         /** Module per query data. */
 103         PyObject* data;
 104 };
 105
 106 /* Generated */
 107 #ifndef S_SPLINT_S
 108 #include "pythonmod/interface.h"
 109 #endif
 110
 111 int pythonmod_init(struct module_env* env, int id)
 112 {
 113    /* Initialize module */
 114    FILE* script_py = NULL;
 115    PyObject* py_cfg, *res;
 116    PyGILState_STATE gil;
 117    struct pythonmod_env* pe = (struct pythonmod_env*)calloc(1, sizeof(struct pythonmod_env));
 118    if (!pe)
 119    {
 120       log_err("pythonmod: malloc failure");
 121       return 0;
 122    }
 123
 124    env->modinfo[id] = (void*) pe;
 125
 126    /* Initialize module */
 127    pe->fname = env->cfg->python_script;
 128    if(pe->fname==NULL || pe->fname[0]==0) {
 129       log_err("pythonmod: no script given.");
 130       return 0;
 131    }
 132
 133    /* Initialize Python libraries */
 134    if (!Py_IsInitialized())
 135    {
 136       Py_SetProgramName("unbound");
 137       Py_NoSiteFlag = 1;
 138       Py_Initialize();
 139       PyEval_InitThreads();
 140       SWIG_init();
 141       pe->mainthr = PyEval_SaveThread();
 142    }
 143
 144    gil = PyGILState_Ensure();
 145
 146    /* Initialize Python */
 147    PyRun_SimpleString("import sys \n");
 148    PyRun_SimpleString("sys.path.append('.') \n");
 149    if(env->cfg->directory && env->cfg->directory[0]) {
 150         char wdir[1524];
 151         snprintf(wdir, sizeof(wdir), "sys.path.append('%s') \n",
 152                 env->cfg->directory);
 153         PyRun_SimpleString(wdir);
 154    }
 155    PyRun_SimpleString("sys.path.append('"RUN_DIR"') \n");
 156    PyRun_SimpleString("sys.path.append('"SHARE_DIR"') \n");
 157    PyRun_SimpleString("import distutils.sysconfig \n");
 158    PyRun_SimpleString("sys.path.append(distutils.sysconfig.get_python_lib(1,0)) \n");
 159    if (PyRun_SimpleString("from unboundmodule import *\n") < 0)
 160    {
 161       log_err("pythonmod: cannot initialize core module: unboundmodule.py");
 162       PyGILState_Release(gil);
 163       return 0;
 164    }
 165
 166    /* Check Python file load */
 167    if ((script_py = fopen(pe->fname, "r")) == NULL)
 168    {
 169       log_err("pythonmod: can't open file %s for reading", pe->fname);
 170       PyGILState_Release(gil);
 171       return 0;
 172    }
 173
 174    /* Load file */
 175    pe->module = PyImport_AddModule("__main__");
 176    pe->dict = PyModule_GetDict(pe->module);
 177    pe->data = Py_None;
 178    Py_INCREF(pe->data);
 179    PyModule_AddObject(pe->module, "mod_env", pe->data);
 180
 181    /* TODO: deallocation of pe->... if an error occurs */
 182
 183    if (PyRun_SimpleFile(script_py, pe->fname) < 0)
 184    {
 185       log_err("pythonmod: can't parse Python script %s", pe->fname);
 186       PyGILState_Release(gil);
 187       return 0;
 188    }
 189
 190    fclose(script_py);
 191
 192    if ((pe->func_init = PyDict_GetItemString(pe->dict, "init")) == NULL)
 193    {
 194       log_err("pythonmod: function init is missing in %s", pe->fname);
 195       PyGILState_Release(gil);
 196       return 0;
 197    }
 198    if ((pe->func_deinit = PyDict_GetItemString(pe->dict, "deinit")) == NULL)
 199    {
 200       log_err("pythonmod: function deinit is missing in %s", pe->fname);
 201       PyGILState_Release(gil);
 202       return 0;
 203    }
 204    if ((pe->func_operate = PyDict_GetItemString(pe->dict, "operate")) == NULL)
 205    {
 206       log_err("pythonmod: function operate is missing in %s", pe->fname);
 207       PyGILState_Release(gil);
 208       return 0;
 209    }
 210    if ((pe->func_inform = PyDict_GetItemString(pe->dict, "inform_super")) == NULL)
 211    {
 212       log_err("pythonmod: function inform_super is missing in %s", pe->fname);
 213       PyGILState_Release(gil);
 214       return 0;
 215    }
 216
 217    py_cfg = SWIG_NewPointerObj((void*) env->cfg, SWIGTYPE_p_config_file, 0);
 218    res = PyObject_CallFunction(pe->func_init, "iO", id, py_cfg);
 219    if (PyErr_Occurred())
 220    {
 221       log_err("pythonmod: Exception occurred in function init");
 222       PyErr_Print();
 223    }
 224
 225    Py_XDECREF(res);
 226    Py_XDECREF(py_cfg);
 227    PyGILState_Release(gil);
 228
 229    return 1;
 230 }
 231
 232 void pythonmod_deinit(struct module_env* env, int id)
 233 {
 234    struct pythonmod_env* pe = env->modinfo[id];
 235    if(pe == NULL)
 236       return;
 237
 238    /* Free Python resources */
 239    if(pe->module != NULL)
 240    {
 241       PyObject* res;
 242       PyGILState_STATE gil = PyGILState_Ensure();
 243
 244       /* Deinit module */
 245       res = PyObject_CallFunction(pe->func_deinit, "i", id);
 246       if (PyErr_Occurred()) {
 247          log_err("pythonmod: Exception occurred in function deinit");
 248          PyErr_Print();
 249       }
 250       /* Free result if any */
 251       Py_XDECREF(res);
 252       /* Free shared data if any */
 253       Py_XDECREF(pe->data);
 254       PyGILState_Release(gil);
 255
 256       PyEval_RestoreThread(pe->mainthr);
 257       Py_Finalize();
 258       pe->mainthr = NULL;
 259    }
 260    pe->fname = NULL;
 261    free(pe);
 262
 263    /* Module is deallocated in Python */
 264    env->modinfo[id] = NULL;
 265 }
 266
 267 void pythonmod_inform_super(struct module_qstate* qstate, int id, struct module_qstate* super)
 268 {
 269    struct pythonmod_env* pe = (struct pythonmod_env*)qstate->env->modinfo[id];
 270    struct pythonmod_qstate* pq = (struct pythonmod_qstate*)qstate->minfo[id];
 271    PyObject* py_qstate, *py_sqstate, *res;
 272    PyGILState_STATE gil = PyGILState_Ensure();
 273
 274    log_query_info(VERB_ALGO, "pythonmod: inform_super, sub is", &qstate->qinfo);
 275    log_query_info(VERB_ALGO, "super is", &super->qinfo);
 276
 277    py_qstate = SWIG_NewPointerObj((void*) qstate, SWIGTYPE_p_module_qstate, 0);
 278    py_sqstate = SWIG_NewPointerObj((void*) super, SWIGTYPE_p_module_qstate, 0);
 279
 280    res = PyObject_CallFunction(pe->func_inform, "iOOO", id, py_qstate,
 281         py_sqstate, pq->data);
 282
 283    if (PyErr_Occurred())
 284    {
 285       log_err("pythonmod: Exception occurred in function inform_super");
 286       PyErr_Print();
 287       qstate->ext_state[id] = module_error;
 288    }
 289    else if ((res == NULL)  || (!PyObject_IsTrue(res)))
 290    {
 291       log_err("pythonmod: python returned bad code in inform_super");
 292       qstate->ext_state[id] = module_error;
 293    }
 294
 295    Py_XDECREF(res);
 296    Py_XDECREF(py_sqstate);
 297    Py_XDECREF(py_qstate);
 298
 299    PyGILState_Release(gil);
 300 }
 301
 302 void pythonmod_operate(struct module_qstate* qstate, enum module_ev event,
 303         int id, struct outbound_entry* ATTR_UNUSED(outbound))
 304 {
 305    struct pythonmod_env* pe = (struct pythonmod_env*)qstate->env->modinfo[id];
 306    struct pythonmod_qstate* pq = (struct pythonmod_qstate*)qstate->minfo[id];
 307    PyObject* py_qstate, *res;
 308    PyGILState_STATE gil = PyGILState_Ensure();
 309
 310    if ( pq == NULL)
 311    {
 312       /* create qstate */
 313       pq = qstate->minfo[id] = malloc(sizeof(struct pythonmod_qstate));
 314
 315       /* Initialize per query data */
 316       pq->data = Py_None;
 317       Py_INCREF(pq->data);
 318    }
 319
 320    /* Call operate */
 321    py_qstate = SWIG_NewPointerObj((void*) qstate, SWIGTYPE_p_module_qstate, 0);
 322    res = PyObject_CallFunction(pe->func_operate, "iiOO", id, (int) event,
 323         py_qstate, pq->data);
 324    if (PyErr_Occurred())
 325    {
 326       log_err("pythonmod: Exception occurred in function operate, event: %s", strmodulevent(event));
 327       PyErr_Print();
 328       qstate->ext_state[id] = module_error;
 329    }
 330    else if ((res == NULL)  || (!PyObject_IsTrue(res)))
 331    {
 332       log_err("pythonmod: python returned bad code, event: %s", strmodulevent(event));
 333       qstate->ext_state[id] = module_error;
 334    }
 335    Py_XDECREF(res);
 336    Py_XDECREF(py_qstate);
 337
 338    PyGILState_Release(gil);
 339 }
 340
 341 void pythonmod_clear(struct module_qstate* qstate, int id)
 342 {
 343    struct pythonmod_qstate* pq;
 344    if (qstate == NULL)
 345       return;
 346
 347    pq = (struct pythonmod_qstate*)qstate->minfo[id];
 348    verbose(VERB_ALGO, "pythonmod: clear, id: %d, pq:%lX", id,
 349         (unsigned long int)pq);
 350    if(pq != NULL)
 351    {
 352       PyGILState_STATE gil = PyGILState_Ensure();
 353       Py_DECREF(pq->data);
 354       PyGILState_Release(gil);
 355       /* Free qstate */
 356       free(pq);
 357    }
 358
 359    qstate->minfo[id] = NULL;
 360 }
 361
 362 size_t pythonmod_get_mem(struct module_env* env, int id)
 363 {
 364    struct pythonmod_env* pe = (struct pythonmod_env*)env->modinfo[id];
 365    verbose(VERB_ALGO, "pythonmod: get_mem, id: %d, pe:%lX", id,
 366         (unsigned long int)pe);
 367    if(!pe)
 368       return 0;
 369    return sizeof(*pe);
 370 }
 371
 372 /**
 373  * The module function block
 374  */
 375 static struct module_func_block pythonmod_block = {
 376    "python",
 377    &pythonmod_init, &pythonmod_deinit, &pythonmod_operate, &pythonmod_inform_super,
 378    &pythonmod_clear, &pythonmod_get_mem
 379 };
 380
 381 struct module_func_block* pythonmod_get_funcblock(void)
 382 {
 383    return &pythonmod_block;
 384 }