source4/dns_server/pydns.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Python DNS server wrapper
   5
   6    Copyright (C) 2015 Andrew Bartlett
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "lib/replace/system/python.h"
  23 #include "python/py3compat.h"
  24 #include "includes.h"
  25 #include "python/modules.h"
  26 #include <pyldb.h>
  27 #include <pytalloc.h>
  28 #include "dns_server/dnsserver_common.h"
  29 #include "dsdb/samdb/samdb.h"
  30 #include "dsdb/common/util.h"
  31 #include "librpc/gen_ndr/ndr_dnsp.h"
  32 #include "librpc/rpc/pyrpc_util.h"
  33
  34 static PyObject *py_dnsp_DnssrvRpcRecord_get_list(struct dnsp_DnssrvRpcRecord *records,
  35                                                   uint16_t num_records)
  36 {
  37         PyObject *py_dns_list;
  38         int i;
  39         py_dns_list = PyList_New(num_records);
  40         if (py_dns_list == NULL) {
  41                 return NULL;
  42         }
  43         for (i = 0; i < num_records; i++) {
  44                 PyObject *py_dns_record;
  45                 py_dns_record = py_return_ndr_struct("samba.dcerpc.dnsp", "DnssrvRpcRecord", records, &records[i]);
  46                 PyList_SetItem(py_dns_list, i, py_dns_record);
  47         }
  48         return py_dns_list;
  49 }
  50
  51
  52 static int py_dnsp_DnssrvRpcRecord_get_array(PyObject *value,
  53                                              TALLOC_CTX *mem_ctx,
  54                                              struct dnsp_DnssrvRpcRecord **records,
  55                                              uint16_t *num_records)
  56 {
  57         int i;
  58         struct dnsp_DnssrvRpcRecord *recs;
  59         PY_CHECK_TYPE(&PyList_Type, value, return -1;);
  60         recs = talloc_array(mem_ctx, struct dnsp_DnssrvRpcRecord,
  61                             PyList_GET_SIZE(value));
  62         if (recs == NULL) {
  63                 PyErr_NoMemory();
  64                 return -1;
  65         }
  66         for (i = 0; i < PyList_GET_SIZE(value); i++) {
  67                 bool type_correct;
  68                 PyObject *item = PyList_GET_ITEM(value, i);
  69                 type_correct = py_check_dcerpc_type(item, "samba.dcerpc.dnsp", "DnssrvRpcRecord");
  70                 if (type_correct == false) {
  71                         return -1;
  72                 }
  73                 if (talloc_reference(mem_ctx, pytalloc_get_mem_ctx(item)) == NULL) {
  74                         PyErr_NoMemory();
  75                         return -1;
  76                 }
  77                 recs[i] = *(struct dnsp_DnssrvRpcRecord *)pytalloc_get_ptr(item);
  78         }
  79         *records = recs;
  80         *num_records = PyList_GET_SIZE(value);
  81         return 0;
  82 }
  83
  84 static PyObject *py_dsdb_dns_lookup(PyObject *self,
  85                                     PyObject *args, PyObject *kwargs)
  86 {
  87         struct ldb_context *samdb;
  88         PyObject *py_ldb, *ret, *pydn;
  89         PyObject *py_dns_partition = NULL;
  90         PyObject *result = NULL;
  91         char *dns_name;
  92         TALLOC_CTX *frame;
  93         NTSTATUS status;
  94         WERROR werr;
  95         struct dns_server_zone *zones_list;
  96         struct ldb_dn *dn, *dns_partition = NULL;
  97         struct dnsp_DnssrvRpcRecord *records;
  98         uint16_t num_records;
  99         const char * const kwnames[] = { "ldb", "dns_name",
 100                                          "dns_partition", NULL };
 101
 102         if (!PyArg_ParseTupleAndKeywords(args, kwargs, "Os|O",
 103                                          discard_const_p(char *, kwnames),
 104                                          &py_ldb, &dns_name,
 105                                          &py_dns_partition)) {
 106                 return NULL;
 107         }
 108         PyErr_LDB_OR_RAISE(py_ldb, samdb);
 109
 110         if (py_dns_partition) {
 111                 PyErr_LDB_DN_OR_RAISE(py_dns_partition,
 112                                       dns_partition);
 113         }
 114
 115         frame = talloc_stackframe();
 116
 117         status = dns_common_zones(samdb, frame, dns_partition,
 118                                   &zones_list);
 119         if (!NT_STATUS_IS_OK(status)) {
 120                 talloc_free(frame);
 121                 PyErr_SetNTSTATUS(status);
 122                 return NULL;
 123         }
 124
 125         werr = dns_common_name2dn(samdb, zones_list, frame, dns_name, &dn);
 126         if (!W_ERROR_IS_OK(werr)) {
 127                 talloc_free(frame);
 128                 PyErr_SetWERROR(werr);
 129                 return NULL;
 130         }
 131
 132         werr = dns_common_lookup(samdb,
 133                                  frame,
 134                                  dn,
 135                                  &records,
 136                                  &num_records,
 137                                  NULL);
 138         if (!W_ERROR_IS_OK(werr)) {
 139                 talloc_free(frame);
 140                 PyErr_SetWERROR(werr);
 141                 return NULL;
 142         }
 143
 144         ret = py_dnsp_DnssrvRpcRecord_get_list(records, num_records);
 145         pydn = pyldb_Dn_FromDn(dn, (PyLdbObject *)py_ldb);
 146         talloc_free(frame);
 147         result = Py_BuildValue("(OO)", pydn, ret);
 148         Py_CLEAR(ret);
 149         Py_CLEAR(pydn);
 150         return result;
 151 }
 152
 153 static PyObject *py_dsdb_dns_extract(PyObject *self, PyObject *args)
 154 {
 155         struct ldb_context *samdb;
 156         PyObject *py_dns_el, *ret;
 157         PyObject *py_ldb = NULL;
 158         TALLOC_CTX *frame;
 159         WERROR werr;
 160         struct ldb_message_element *dns_el;
 161         struct dnsp_DnssrvRpcRecord *records;
 162         uint16_t num_records;
 163
 164         if (!PyArg_ParseTuple(args, "OO", &py_ldb, &py_dns_el)) {
 165                 return NULL;
 166         }
 167
 168         PyErr_LDB_OR_RAISE(py_ldb, samdb);
 169
 170         if (!py_check_dcerpc_type(py_dns_el, "ldb", "MessageElement")) {
 171                 PyErr_SetString(PyExc_TypeError,
 172                                 "ldb MessageElement object required");
 173                 return NULL;
 174         }
 175         dns_el = pyldb_MessageElement_AsMessageElement(py_dns_el);
 176
 177         frame = talloc_stackframe();
 178
 179         werr = dns_common_extract(samdb, dns_el,
 180                                   frame,
 181                                   &records,
 182                                   &num_records);
 183         if (!W_ERROR_IS_OK(werr)) {
 184                 talloc_free(frame);
 185                 PyErr_SetWERROR(werr);
 186                 return NULL;
 187         }
 188
 189         ret = py_dnsp_DnssrvRpcRecord_get_list(records, num_records);
 190         talloc_free(frame);
 191         return ret;
 192 }
 193
 194 static PyObject *py_dsdb_dns_replace(PyObject *self, PyObject *args)
 195 {
 196         struct ldb_context *samdb;
 197         PyObject *py_ldb, *py_dns_records;
 198         char *dns_name;
 199         TALLOC_CTX *frame;
 200         NTSTATUS status;
 201         WERROR werr;
 202         int ret;
 203         struct dns_server_zone *zones_list;
 204         struct ldb_dn *dn;
 205         struct dnsp_DnssrvRpcRecord *records;
 206         uint16_t num_records;
 207
 208         /*
 209          * TODO: This is a shocking abuse, but matches what the
 210          * internal DNS server does, it should be pushed into
 211          * dns_common_replace()
 212          */
 213         static const int serial = 110;
 214
 215         if (!PyArg_ParseTuple(args, "OsO", &py_ldb, &dns_name, &py_dns_records)) {
 216                 return NULL;
 217         }
 218         PyErr_LDB_OR_RAISE(py_ldb, samdb);
 219
 220         frame = talloc_stackframe();
 221
 222         status = dns_common_zones(samdb, frame, NULL, &zones_list);
 223         if (!NT_STATUS_IS_OK(status)) {
 224                 PyErr_SetNTSTATUS(status);
 225                 talloc_free(frame);
 226                 return NULL;
 227         }
 228
 229         werr = dns_common_name2dn(samdb, zones_list, frame, dns_name, &dn);
 230         if (!W_ERROR_IS_OK(werr)) {
 231                 PyErr_SetWERROR(werr);
 232                 talloc_free(frame);
 233                 return NULL;
 234         }
 235
 236         ret = py_dnsp_DnssrvRpcRecord_get_array(py_dns_records,
 237                                                 frame,
 238                                                 &records, &num_records);
 239         if (ret != 0) {
 240                 talloc_free(frame);
 241                 return NULL;
 242         }
 243
 244         werr = dns_common_replace(samdb,
 245                                   frame,
 246                                   dn,
 247                                   false, /* Not adding a record */
 248                                   serial,
 249                                   records,
 250                                   num_records);
 251         if (!W_ERROR_IS_OK(werr)) {
 252                 PyErr_SetWERROR(werr);
 253                 talloc_free(frame);
 254                 return NULL;
 255         }
 256
 257         talloc_free(frame);
 258         Py_RETURN_NONE;
 259 }
 260
 261 static PyObject *py_dsdb_dns_replace_by_dn(PyObject *self, PyObject *args)
 262 {
 263         struct ldb_context *samdb;
 264         PyObject *py_ldb, *py_dn, *py_dns_records;
 265         TALLOC_CTX *frame;
 266         WERROR werr;
 267         int ret;
 268         struct ldb_dn *dn;
 269         struct dnsp_DnssrvRpcRecord *records;
 270         uint16_t num_records;
 271
 272         /*
 273          * TODO: This is a shocking abuse, but matches what the
 274          * internal DNS server does, it should be pushed into
 275          * dns_common_replace()
 276          */
 277         static const int serial = 110;
 278
 279         if (!PyArg_ParseTuple(args, "OOO", &py_ldb, &py_dn, &py_dns_records)) {
 280                 return NULL;
 281         }
 282         PyErr_LDB_OR_RAISE(py_ldb, samdb);
 283
 284         PyErr_LDB_DN_OR_RAISE(py_dn, dn);
 285
 286         frame = talloc_stackframe();
 287
 288         ret = py_dnsp_DnssrvRpcRecord_get_array(py_dns_records,
 289                                                 frame,
 290                                                 &records, &num_records);
 291         if (ret != 0) {
 292                 talloc_free(frame);
 293                 return NULL;
 294         }
 295
 296         werr = dns_common_replace(samdb,
 297                                   frame,
 298                                   dn,
 299                                   false, /* Not adding a node */
 300                                   serial,
 301                                   records,
 302                                   num_records);
 303         if (!W_ERROR_IS_OK(werr)) {
 304                 PyErr_SetWERROR(werr);
 305                 talloc_free(frame);
 306                 return NULL;
 307         }
 308
 309         talloc_free(frame);
 310
 311         Py_RETURN_NONE;
 312 }
 313
 314
 315 static PyObject *py_dsdb_dns_records_match(PyObject *self, PyObject *args)
 316 {
 317         PyObject *py_recs[2];
 318         struct dnsp_DnssrvRpcRecord *rec1;
 319         struct dnsp_DnssrvRpcRecord *rec2;
 320         size_t i;
 321         bool type_correct;
 322         bool match;
 323
 324         if (!PyArg_ParseTuple(args, "OO", &py_recs[0], &py_recs[1])) {
 325                 return NULL;
 326         }
 327
 328         for (i = 0; i < 2; i++) {
 329                 type_correct = py_check_dcerpc_type(py_recs[i],
 330                                                     "samba.dcerpc.dnsp",
 331                                                     "DnssrvRpcRecord");
 332                 if (! type_correct) {
 333                         PyErr_SetString(PyExc_ValueError,
 334                                         "DnssrvRpcRecord expected");
 335                         return NULL;
 336                 }
 337         }
 338
 339         rec1 = (struct dnsp_DnssrvRpcRecord *)pytalloc_get_ptr(py_recs[0]);
 340         rec2 = (struct dnsp_DnssrvRpcRecord *)pytalloc_get_ptr(py_recs[1]);
 341
 342         match = dns_record_match(rec1, rec2);
 343         return PyBool_FromLong(match);
 344 }
 345
 346
 347 static PyObject *py_dsdb_dns_unix_to_dns_timestamp(PyObject *self, PyObject *args)
 348 {
 349         uint32_t timestamp;
 350         time_t t;
 351         long long lt;
 352
 353         if (!PyArg_ParseTuple(args, "L", &lt)) {
 354                 return NULL;
 355         }
 356
 357         t = lt;
 358         if (t != lt) {
 359                 /* time_t is presumably 32 bit here */
 360                 PyErr_SetString(PyExc_ValueError, "Time out of range");
 361                 return NULL;
 362         }
 363         timestamp = unix_to_dns_timestamp(t);
 364         return Py_BuildValue("k", (unsigned long) timestamp);
 365 }
 366
 367 static PyObject *py_dsdb_dns_timestamp_to_nt_time(PyObject *self, PyObject *args)
 368 {
 369         unsigned long long timestamp;
 370         NTSTATUS status;
 371         NTTIME nt;
 372         if (!PyArg_ParseTuple(args, "K", &timestamp)) {
 373                 return NULL;
 374         }
 375
 376         if (timestamp > UINT32_MAX) {
 377                 PyErr_SetString(PyExc_ValueError, "Time out of range");
 378                 return NULL;
 379         }
 380         status = dns_timestamp_to_nt_time(&nt, (uint32_t)timestamp);
 381         if (!NT_STATUS_IS_OK(status)) {
 382                 PyErr_SetString(PyExc_ValueError, "Time out of range");
 383                 return NULL;
 384         }
 385         return Py_BuildValue("L", (long long) nt);
 386 }
 387
 388
 389 static PyMethodDef py_dsdb_dns_methods[] = {
 390
 391         { "lookup", PY_DISCARD_FUNC_SIG(PyCFunction, py_dsdb_dns_lookup),
 392                 METH_VARARGS|METH_KEYWORDS,
 393                 "Get the DNS database entries for a DNS name"},
 394         { "replace", (PyCFunction)py_dsdb_dns_replace,
 395                 METH_VARARGS, "Replace the DNS database entries for a DNS name"},
 396         { "replace_by_dn", (PyCFunction)py_dsdb_dns_replace_by_dn,
 397                 METH_VARARGS, "Replace the DNS database entries for a LDB DN"},
 398         { "records_match", (PyCFunction)py_dsdb_dns_records_match,
 399           METH_VARARGS|METH_KEYWORDS,
 400           "Decide whether two records match, according to dns update rules"},
 401         { "extract", (PyCFunction)py_dsdb_dns_extract,
 402                 METH_VARARGS, "Return the DNS database entry as a python structure from an Ldb.MessageElement of type dnsRecord"},
 403         { "unix_to_dns_timestamp", (PyCFunction)py_dsdb_dns_unix_to_dns_timestamp,
 404           METH_VARARGS,
 405           "Convert a time.time() value to a dns timestamp (hours since 1601)"},
 406         { "dns_timestamp_to_nt_time", (PyCFunction)py_dsdb_dns_timestamp_to_nt_time,
 407           METH_VARARGS,
 408           "Convert a dns timestamp to an NTTIME value"},
 409         {0}
 410 };
 411
 412 static struct PyModuleDef moduledef = {
 413     PyModuleDef_HEAD_INIT,
 414     .m_name = "dsdb_dns",
 415     .m_doc = "Python bindings for the DNS objects in the directory service databases.",
 416     .m_size = -1,
 417     .m_methods = py_dsdb_dns_methods,
 418 };
 419
 420 MODULE_INIT_FUNC(dsdb_dns)
 421 {
 422         PyObject *m;
 423
 424         m = PyModule_Create(&moduledef);
 425
 426         if (m == NULL)
 427                 return NULL;
 428
 429         return m;
 430 }