python/pyglue.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Copyright (C) Jelmer Vernooij <jelmer@samba.org> 2007
   4    Copyright (C) Matthias Dieter Wallnöfer          2009
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "lib/replace/system/python.h"
  21 #include "python/py3compat.h"
  22 #include "includes.h"
  23 #include "python/modules.h"
  24 #include "version.h"
  25 #include "param/pyparam.h"
  26 #include "lib/socket/netif.h"
  27 #include "lib/util/debug.h"
  28 #include "librpc/ndr/ndr_private.h"
  29 #include "lib/cmdline/cmdline.h"
  30 #include "lib/crypto/gkdi.h"
  31
  32 static PyObject *py_generate_random_str(PyObject *self, PyObject *args)
  33 {
  34         Py_ssize_t len;
  35         PyObject *ret;
  36         char *retstr;
  37
  38         if (!PyArg_ParseTuple(args, "n", &len)) {
  39                 return NULL;
  40         }
  41         if (len < 0) {
  42                 PyErr_Format(PyExc_ValueError,
  43                              "random string length should be positive, not %zd",
  44                              len);
  45                 return NULL;
  46         }
  47         retstr = generate_random_str(NULL, len);
  48         if (retstr == NULL) {
  49                 return PyErr_NoMemory();
  50         }
  51         ret = PyUnicode_FromStringAndSize(retstr, len);
  52         talloc_free(retstr);
  53         return ret;
  54 }
  55
  56 static PyObject *py_generate_random_password(PyObject *self, PyObject *args)
  57 {
  58         Py_ssize_t min, max;
  59         PyObject *ret;
  60         char *retstr;
  61
  62         if (!PyArg_ParseTuple(args, "nn", &min, &max)) {
  63                 return NULL;
  64         }
  65         if (max < 0 || min < 0) {
  66                 /*
  67                  * The real range checks happens in generate_random_password().
  68                  * Here just filter out any negative numbers.
  69                  */
  70                 PyErr_Format(PyExc_ValueError,
  71                              "invalid range: %zd - %zd",
  72                              min, max);
  73                 return NULL;
  74         }
  75
  76         retstr = generate_random_password(NULL, min, max);
  77         if (retstr == NULL) {
  78                 if (errno == EINVAL) {
  79                         return PyErr_Format(PyExc_ValueError,
  80                                             "invalid range: %zd - %zd",
  81                                             min, max);
  82                 }
  83                 return PyErr_NoMemory();
  84         }
  85         ret = PyUnicode_FromString(retstr);
  86         talloc_free(retstr);
  87         return ret;
  88 }
  89
  90 static PyObject *py_generate_random_machine_password(PyObject *self, PyObject *args)
  91 {
  92         Py_ssize_t min, max;
  93         PyObject *ret;
  94         char *retstr;
  95
  96         if (!PyArg_ParseTuple(args, "nn", &min, &max)) {
  97                 return NULL;
  98         }
  99         if (max < 0 || min < 0) {
 100                 /*
 101                  * The real range checks happens in
 102                  * generate_random_machine_password().
 103                  * Here we just filter out any negative numbers.
 104                  */
 105                 PyErr_Format(PyExc_ValueError,
 106                              "invalid range: %zd - %zd",
 107                              min, max);
 108                 return NULL;
 109         }
 110
 111         retstr = generate_random_machine_password(NULL, min, max);
 112         if (retstr == NULL) {
 113                 if (errno == EINVAL) {
 114                         return PyErr_Format(PyExc_ValueError,
 115                                             "invalid range: %zd - %zd",
 116                                             min, max);
 117                 }
 118                 return PyErr_NoMemory();
 119         }
 120         ret = PyUnicode_FromString(retstr);
 121         talloc_free(retstr);
 122         return ret;
 123 }
 124
 125 static PyObject *py_check_password_quality(PyObject *self, PyObject *args)
 126 {
 127         char *pass;
 128
 129         if (!PyArg_ParseTuple(args, "s", &pass)) {
 130                 return NULL;
 131         }
 132
 133         return PyBool_FromLong(check_password_quality(pass));
 134 }
 135
 136 static PyObject *py_generate_random_bytes(PyObject *self, PyObject *args)
 137 {
 138         Py_ssize_t len;
 139         PyObject *ret;
 140         uint8_t *bytes = NULL;
 141
 142         if (!PyArg_ParseTuple(args, "n", &len)) {
 143                 return NULL;
 144         }
 145         if (len < 0) {
 146                 PyErr_Format(PyExc_ValueError,
 147                              "random bytes length should be positive, not %zd",
 148                              len);
 149                 return NULL;
 150         }
 151         bytes = talloc_zero_size(NULL, len);
 152         if (bytes == NULL) {
 153                 PyErr_NoMemory();
 154                 return NULL;
 155         }
 156         generate_random_buffer(bytes, len);
 157         ret = PyBytes_FromStringAndSize((const char *)bytes, len);
 158         talloc_free(bytes);
 159         return ret;
 160 }
 161
 162 static PyObject *py_unix2nttime(PyObject *self, PyObject *args)
 163 {
 164         time_t t;
 165         unsigned int _t;
 166         NTTIME nt;
 167
 168         if (!PyArg_ParseTuple(args, "I", &_t)) {
 169                 return NULL;
 170         }
 171         t = _t;
 172
 173         unix_to_nt_time(&nt, t);
 174
 175         return PyLong_FromLongLong((uint64_t)nt);
 176 }
 177
 178 static PyObject *py_nttime2unix(PyObject *self, PyObject *args)
 179 {
 180         time_t t;
 181         NTTIME nt;
 182         if (!PyArg_ParseTuple(args, "K", &nt))
 183                 return NULL;
 184
 185         t = nt_time_to_unix(nt);
 186
 187         return PyLong_FromLong((uint64_t)t);
 188 }
 189
 190 static PyObject *py_float2nttime(PyObject *self, PyObject *args)
 191 {
 192         double ft = 0;
 193         double ft_sec = 0;
 194         double ft_nsec = 0;
 195         struct timespec ts;
 196         NTTIME nt = 0;
 197
 198         if (!PyArg_ParseTuple(args, "d", &ft)) {
 199                 return NULL;
 200         }
 201
 202         ft_sec = (double)(int)ft;
 203         ft_nsec = (ft - ft_sec) * 1.0e+9;
 204
 205         ts.tv_sec = (int)ft_sec;
 206         ts.tv_nsec = (int)ft_nsec;
 207
 208         nt = full_timespec_to_nt_time(&ts);
 209
 210         return PyLong_FromLongLong((uint64_t)nt);
 211 }
 212
 213 static PyObject *py_nttime2float(PyObject *self, PyObject *args)
 214 {
 215         double ft = 0;
 216         struct timespec ts;
 217         const struct timespec ts_zero = { .tv_sec = 0, };
 218         NTTIME nt = 0;
 219
 220         if (!PyArg_ParseTuple(args, "K", &nt)) {
 221                 return NULL;
 222         }
 223
 224         ts = nt_time_to_full_timespec(nt);
 225         if (is_omit_timespec(&ts)) {
 226                 return PyFloat_FromDouble(1.0);
 227         }
 228         ft = timespec_elapsed2(&ts_zero, &ts);
 229
 230         return PyFloat_FromDouble(ft);
 231 }
 232
 233 static PyObject *py_nttime2string(PyObject *self, PyObject *args)
 234 {
 235         PyObject *ret;
 236         NTTIME nt;
 237         TALLOC_CTX *tmp_ctx;
 238         const char *string;
 239         if (!PyArg_ParseTuple(args, "K", &nt))
 240                 return NULL;
 241
 242         tmp_ctx = talloc_new(NULL);
 243         if (tmp_ctx == NULL) {
 244                 PyErr_NoMemory();
 245                 return NULL;
 246         }
 247
 248         string = nt_time_string(tmp_ctx, nt);
 249         ret =  PyUnicode_FromString(string);
 250
 251         talloc_free(tmp_ctx);
 252
 253         return ret;
 254 }
 255
 256 static PyObject *py_set_debug_level(PyObject *self, PyObject *args)
 257 {
 258         unsigned level;
 259         if (!PyArg_ParseTuple(args, "I", &level))
 260                 return NULL;
 261         debuglevel_set(level);
 262         Py_RETURN_NONE;
 263 }
 264
 265 static PyObject *py_get_debug_level(PyObject *self,
 266                 PyObject *Py_UNUSED(ignored))
 267 {
 268         return PyLong_FromLong(debuglevel_get());
 269 }
 270
 271 static PyObject *py_fault_setup(PyObject *self,
 272                 PyObject *Py_UNUSED(ignored))
 273 {
 274         static bool done;
 275         if (!done) {
 276                 fault_setup();
 277                 done = true;
 278         }
 279         Py_RETURN_NONE;
 280 }
 281
 282 static PyObject *py_is_ntvfs_fileserver_built(PyObject *self,
 283                 PyObject *Py_UNUSED(ignored))
 284 {
 285 #ifdef WITH_NTVFS_FILESERVER
 286         Py_RETURN_TRUE;
 287 #else
 288         Py_RETURN_FALSE;
 289 #endif
 290 }
 291
 292 static PyObject *py_is_heimdal_built(PyObject *self,
 293                 PyObject *Py_UNUSED(ignored))
 294 {
 295 #ifdef SAMBA4_USES_HEIMDAL
 296         Py_RETURN_TRUE;
 297 #else
 298         Py_RETURN_FALSE;
 299 #endif
 300 }
 301
 302 static PyObject *py_is_ad_dc_built(PyObject *self,
 303                 PyObject *Py_UNUSED(ignored))
 304 {
 305 #ifdef AD_DC_BUILD_IS_ENABLED
 306         Py_RETURN_TRUE;
 307 #else
 308         Py_RETURN_FALSE;
 309 #endif
 310 }
 311
 312 static PyObject *py_is_rust_built(PyObject *self,
 313                 PyObject *Py_UNUSED(ignored))
 314 {
 315 #ifdef HAVE_RUST
 316         Py_RETURN_TRUE;
 317 #else
 318         Py_RETURN_FALSE;
 319 #endif
 320 }
 321
 322 static PyObject *py_is_selftest_enabled(PyObject *self,
 323                 PyObject *Py_UNUSED(ignored))
 324 {
 325 #ifdef ENABLE_SELFTEST
 326         Py_RETURN_TRUE;
 327 #else
 328         Py_RETURN_FALSE;
 329 #endif
 330 }
 331
 332 static PyObject *py_ndr_token_max_list_size(PyObject *self,
 333                 PyObject *Py_UNUSED(ignored))
 334 {
 335         return PyLong_FromLong(ndr_token_max_list_size());
 336 }
 337
 338 /*
 339   return the list of interface IPs we have configured
 340   takes an loadparm context, returns a list of IPs in string form
 341
 342   Does not return addresses on 127.0.0.0/8
 343  */
 344 static PyObject *py_interface_ips(PyObject *self, PyObject *args)
 345 {
 346         PyObject *pylist;
 347         int count;
 348         TALLOC_CTX *tmp_ctx;
 349         PyObject *py_lp_ctx;
 350         struct loadparm_context *lp_ctx;
 351         struct interface *ifaces;
 352         int i, ifcount;
 353         int all_interfaces = 1;
 354
 355         if (!PyArg_ParseTuple(args, "O|i", &py_lp_ctx, &all_interfaces))
 356                 return NULL;
 357
 358         tmp_ctx = talloc_new(NULL);
 359         if (tmp_ctx == NULL) {
 360                 PyErr_NoMemory();
 361                 return NULL;
 362         }
 363
 364         lp_ctx = lpcfg_from_py_object(tmp_ctx, py_lp_ctx);
 365         if (lp_ctx == NULL) {
 366                 talloc_free(tmp_ctx);
 367                 return PyErr_NoMemory();
 368         }
 369
 370         load_interface_list(tmp_ctx, lp_ctx, &ifaces);
 371
 372         count = iface_list_count(ifaces);
 373
 374         /* first count how many are not loopback addresses */
 375         for (ifcount = i = 0; i<count; i++) {
 376                 const char *ip = iface_list_n_ip(ifaces, i);
 377
 378                 if (all_interfaces) {
 379                         ifcount++;
 380                         continue;
 381                 }
 382
 383                 if (iface_list_same_net(ip, "127.0.0.1", "255.0.0.0")) {
 384                         continue;
 385                 }
 386
 387                 if (iface_list_same_net(ip, "169.254.0.0", "255.255.0.0")) {
 388                         continue;
 389                 }
 390
 391                 if (iface_list_same_net(ip, "::1", "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff")) {
 392                         continue;
 393                 }
 394
 395                 if (iface_list_same_net(ip, "fe80::", "ffff:ffff:ffff:ffff::")) {
 396                         continue;
 397                 }
 398
 399                 ifcount++;
 400         }
 401
 402         pylist = PyList_New(ifcount);
 403         for (ifcount = i = 0; i<count; i++) {
 404                 const char *ip = iface_list_n_ip(ifaces, i);
 405
 406                 if (all_interfaces) {
 407                         PyList_SetItem(pylist, ifcount, PyUnicode_FromString(ip));
 408                         ifcount++;
 409                         continue;
 410                 }
 411
 412                 if (iface_list_same_net(ip, "127.0.0.1", "255.0.0.0")) {
 413                         continue;
 414                 }
 415
 416                 if (iface_list_same_net(ip, "169.254.0.0", "255.255.0.0")) {
 417                         continue;
 418                 }
 419
 420                 if (iface_list_same_net(ip, "::1", "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff")) {
 421                         continue;
 422                 }
 423
 424                 if (iface_list_same_net(ip, "fe80::", "ffff:ffff:ffff:ffff::")) {
 425                         continue;
 426                 }
 427
 428                 PyList_SetItem(pylist, ifcount, PyUnicode_FromString(ip));
 429                 ifcount++;
 430         }
 431         talloc_free(tmp_ctx);
 432         return pylist;
 433 }
 434
 435 static PyObject *py_strcasecmp_m(PyObject *self, PyObject *args)
 436 {
 437         char *s1 = NULL;
 438         char *s2 = NULL;
 439         long cmp_result = 0;
 440         if (!PyArg_ParseTuple(args, PYARG_STR_UNI
 441                               PYARG_STR_UNI,
 442                               "utf8", &s1, "utf8", &s2)) {
 443                 return NULL;
 444         }
 445
 446         cmp_result = strcasecmp_m(s1, s2);
 447         PyMem_Free(s1);
 448         PyMem_Free(s2);
 449         return PyLong_FromLong(cmp_result);
 450 }
 451
 452 static PyObject *py_strstr_m(PyObject *self, PyObject *args)
 453 {
 454         char *s1 = NULL;
 455         char *s2 = NULL;
 456         char *strstr_ret = NULL;
 457         PyObject *result = NULL;
 458         if (!PyArg_ParseTuple(args, PYARG_STR_UNI
 459                               PYARG_STR_UNI,
 460                               "utf8", &s1, "utf8", &s2))
 461                 return NULL;
 462
 463         strstr_ret = strstr_m(s1, s2);
 464         if (!strstr_ret) {
 465                 PyMem_Free(s1);
 466                 PyMem_Free(s2);
 467                 Py_RETURN_NONE;
 468         }
 469         result = PyUnicode_FromString(strstr_ret);
 470         PyMem_Free(s1);
 471         PyMem_Free(s2);
 472         return result;
 473 }
 474
 475 static PyObject *py_get_burnt_commandline(PyObject *self, PyObject *args)
 476 {
 477         PyObject *cmdline_as_list, *ret;
 478         char *burnt_cmdline = NULL;
 479         Py_ssize_t i, argc;
 480         char **argv = NULL;
 481         TALLOC_CTX *frame = talloc_stackframe();
 482         bool burnt;
 483
 484         if (!PyArg_ParseTuple(args, "O!", &PyList_Type, &cmdline_as_list))
 485         {
 486                 TALLOC_FREE(frame);
 487                 return NULL;
 488         }
 489
 490         argc = PyList_GET_SIZE(cmdline_as_list);
 491
 492         if (argc == 0) {
 493                 TALLOC_FREE(frame);
 494                 Py_RETURN_NONE;
 495         }
 496
 497         argv = PyList_AsStringList(frame, cmdline_as_list, "sys.argv");
 498         if (argv == NULL) {
 499                 TALLOC_FREE(frame);
 500                 return NULL;
 501         }
 502
 503         burnt = samba_cmdline_burn(argc, argv);
 504         if (!burnt) {
 505                 TALLOC_FREE(frame);
 506                 Py_RETURN_NONE;
 507         }
 508
 509         for (i = 0; i < argc; i++) {
 510                 if (i == 0) {
 511                         burnt_cmdline = talloc_strdup(frame,
 512                                                       argv[i]);
 513                 } else {
 514                         burnt_cmdline
 515                                 = talloc_asprintf_append(burnt_cmdline,
 516                                                          " %s",
 517                                                          argv[i]);
 518                 }
 519                 if (burnt_cmdline == NULL) {
 520                         PyErr_NoMemory();
 521                         TALLOC_FREE(frame);
 522                         return NULL;
 523                 }
 524         }
 525
 526         ret = PyUnicode_FromString(burnt_cmdline);
 527         TALLOC_FREE(frame);
 528
 529         return ret;
 530 }
 531
 532 static PyMethodDef py_misc_methods[] = {
 533         { "generate_random_str", (PyCFunction)py_generate_random_str, METH_VARARGS,
 534                 "generate_random_str(len) -> string\n"
 535                 "Generate random string with specified length." },
 536         { "generate_random_password", (PyCFunction)py_generate_random_password,
 537                 METH_VARARGS, "generate_random_password(min, max) -> string\n"
 538                 "Generate random password (based on printable ascii characters) "
 539                 "with a length >= min and <= max." },
 540         { "generate_random_machine_password", (PyCFunction)py_generate_random_machine_password,
 541                 METH_VARARGS, "generate_random_machine_password(min, max) -> string\n"
 542                 "Generate random password "
 543                 "(based on random utf16 characters converted to utf8 or "
 544                 "random ascii characters if 'unix charset' is not 'utf8') "
 545                 "with a length >= min (at least 14) and <= max (at most 255)." },
 546         { "check_password_quality", (PyCFunction)py_check_password_quality,
 547                 METH_VARARGS, "check_password_quality(pass) -> bool\n"
 548                 "Check password quality against Samba's check_password_quality, "
 549                 "the implementation of Microsoft's rules: "
 550                 "http://msdn.microsoft.com/en-us/subscriptions/cc786468%28v=ws.10%29.aspx"
 551         },
 552         { "unix2nttime", (PyCFunction)py_unix2nttime, METH_VARARGS,
 553                 "unix2nttime(timestamp) -> nttime" },
 554         { "nttime2unix", (PyCFunction)py_nttime2unix, METH_VARARGS,
 555                 "nttime2unix(nttime) -> timestamp" },
 556         { "float2nttime", (PyCFunction)py_float2nttime, METH_VARARGS,
 557                 "pytime2nttime(floattimestamp) -> nttime" },
 558         { "nttime2float", (PyCFunction)py_nttime2float, METH_VARARGS,
 559                 "nttime2pytime(nttime) -> floattimestamp" },
 560         { "nttime2string", (PyCFunction)py_nttime2string, METH_VARARGS,
 561                 "nttime2string(nttime) -> string" },
 562         { "set_debug_level", (PyCFunction)py_set_debug_level, METH_VARARGS,
 563                 "set debug level" },
 564         { "get_debug_level", (PyCFunction)py_get_debug_level, METH_NOARGS,
 565                 "get debug level" },
 566         { "fault_setup", (PyCFunction)py_fault_setup, METH_NOARGS,
 567                 "setup the default samba panic handler" },
 568         { "interface_ips", (PyCFunction)py_interface_ips, METH_VARARGS,
 569                 "interface_ips(lp_ctx[, all_interfaces) -> list_of_ifaces\n"
 570                 "\n"
 571                 "get interface IP address list"},
 572         { "strcasecmp_m", (PyCFunction)py_strcasecmp_m, METH_VARARGS,
 573                 "(for testing) compare two strings using Samba's strcasecmp_m()"},
 574         { "strstr_m", (PyCFunction)py_strstr_m, METH_VARARGS,
 575                 "(for testing) find one string in another with Samba's strstr_m()"},
 576         { "is_ntvfs_fileserver_built", (PyCFunction)py_is_ntvfs_fileserver_built, METH_NOARGS,
 577                 "is the NTVFS file server built in this installation?" },
 578         { "is_heimdal_built", (PyCFunction)py_is_heimdal_built, METH_NOARGS,
 579                 "is Samba built with Heimdal Kerberos?" },
 580         { "generate_random_bytes",
 581                 (PyCFunction)py_generate_random_bytes,
 582                 METH_VARARGS,
 583                 "generate_random_bytes(len) -> bytes\n"
 584                 "Generate random bytes with specified length." },
 585         { "is_ad_dc_built", (PyCFunction)py_is_ad_dc_built, METH_NOARGS,
 586                 "is Samba built with AD DC?" },
 587         { "is_selftest_enabled", (PyCFunction)py_is_selftest_enabled,
 588                 METH_NOARGS, "is Samba built with selftest enabled?" },
 589         { "ndr_token_max_list_size", (PyCFunction)py_ndr_token_max_list_size,
 590                 METH_NOARGS, "How many NDR internal tokens is too many for this build?" },
 591         { "get_burnt_commandline", (PyCFunction)py_get_burnt_commandline,
 592                 METH_VARARGS, "Return a redacted commandline to feed to setproctitle (None if no redaction required)" },
 593         { "is_rust_built", (PyCFunction)py_is_rust_built, METH_NOARGS,
 594                 "is Samba built with Rust?" },
 595         {0}
 596 };
 597
 598 static struct PyModuleDef moduledef = {
 599     PyModuleDef_HEAD_INIT,
 600     .m_name = "_glue",
 601     .m_doc = "Python bindings for miscellaneous Samba functions.",
 602     .m_size = -1,
 603     .m_methods = py_misc_methods,
 604 };
 605
 606 MODULE_INIT_FUNC(_glue)
 607 {
 608         PyObject *m;
 609         PyObject *py_obj = NULL;
 610         int ret;
 611
 612         debug_setup_talloc_log();
 613
 614         m = PyModule_Create(&moduledef);
 615         if (m == NULL)
 616                 return NULL;
 617
 618         PyModule_AddObject(m, "version",
 619                                            PyUnicode_FromString(SAMBA_VERSION_STRING));
 620         py_obj = PyErr_NewException("samba.NTSTATUSError", PyExc_RuntimeError, NULL);
 621         if (py_obj != NULL) {
 622                 PyModule_AddObject(m, "NTSTATUSError", py_obj);
 623         }
 624
 625         py_obj = PyErr_NewException("samba.WERRORError", PyExc_RuntimeError, NULL);
 626         if (py_obj != NULL) {
 627                 PyModule_AddObject(m, "WERRORError", py_obj);
 628         }
 629
 630         py_obj = PyErr_NewException("samba.HRESULTError", PyExc_RuntimeError, NULL);
 631         if (py_obj != NULL) {
 632                 PyModule_AddObject(m, "HRESULTError", py_obj);
 633         }
 634
 635         py_obj = PyErr_NewException("samba.DsExtendedError", PyExc_RuntimeError, NULL);
 636         if (py_obj != NULL) {
 637                 PyModule_AddObject(m, "DsExtendedError", py_obj);
 638         }
 639
 640         ret = PyModule_AddIntConstant(m, "GKDI_L1_KEY_ITERATION", gkdi_l1_key_iteration);
 641         if (ret) {
 642                 Py_DECREF(m);
 643                 return NULL;
 644         }
 645         ret = PyModule_AddIntConstant(m, "GKDI_L2_KEY_ITERATION", gkdi_l2_key_iteration);
 646         if (ret) {
 647                 Py_DECREF(m);
 648                 return NULL;
 649         }
 650         py_obj = PyLong_FromLongLong(gkdi_key_cycle_duration);
 651         if (py_obj == NULL) {
 652                 Py_DECREF(m);
 653                 return NULL;
 654         }
 655         ret = PyModule_AddObject(m, "GKDI_KEY_CYCLE_DURATION", py_obj);
 656         if (ret) {
 657                 Py_DECREF(py_obj);
 658                 Py_DECREF(m);
 659                 return NULL;
 660         }
 661         py_obj = PyLong_FromLongLong(gkdi_max_clock_skew);
 662         if (py_obj == NULL) {
 663                 Py_DECREF(m);
 664                 return NULL;
 665         }
 666         ret = PyModule_AddObject(m, "GKDI_MAX_CLOCK_SKEW", py_obj);
 667         if (ret) {
 668                 Py_DECREF(py_obj);
 669                 Py_DECREF(m);
 670                 return NULL;
 671         }
 672
 673         return m;
 674 }