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 <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 /* FIXME: These should be in a header file somewhere */
  35 #define PyErr_LDB_OR_RAISE(py_ldb, ldb) \
  36         if (!py_check_dcerpc_type(py_ldb, "ldb", "Ldb")) { \
  37                 PyErr_SetString(PyExc_TypeError, "Ldb connection object required"); \
  38                 return NULL; \
  39         } \
  40         ldb = pyldb_Ldb_AsLdbContext(py_ldb);
  41
  42 #define PyErr_LDB_DN_OR_RAISE(py_ldb_dn, dn) \
  43         if (!py_check_dcerpc_type(py_ldb_dn, "ldb", "Dn")) { \
  44                 PyErr_SetString(PyExc_TypeError, "ldb Dn object required"); \
  45                 return NULL; \
  46         } \
  47         dn = pyldb_Dn_AS_DN(py_ldb_dn);
  48
  49 static PyObject *py_dnsp_DnssrvRpcRecord_get_list(struct dnsp_DnssrvRpcRecord *records,
  50                                                   uint16_t num_records)
  51 {
  52         PyObject *py_dns_list;
  53         int i;
  54         py_dns_list = PyList_New(num_records);
  55         if (py_dns_list == NULL) {
  56                 return NULL;
  57         }
  58         for (i = 0; i < num_records; i++) {
  59                 PyObject *py_dns_record;
  60                 py_dns_record = py_return_ndr_struct("samba.dcerpc.dnsp", "DnssrvRpcRecord", records, &records[i]);
  61                 PyList_SetItem(py_dns_list, i, py_dns_record);
  62         }
  63         return py_dns_list;
  64 }
  65
  66
  67 static int py_dnsp_DnssrvRpcRecord_get_array(PyObject *value,
  68                                              TALLOC_CTX *mem_ctx,
  69                                              struct dnsp_DnssrvRpcRecord **records,
  70                                              uint16_t *num_records)
  71 {
  72         int i;
  73         struct dnsp_DnssrvRpcRecord *recs;
  74         PY_CHECK_TYPE(&PyList_Type, value, return -1;);
  75         recs = talloc_array(mem_ctx, struct dnsp_DnssrvRpcRecord,
  76                             PyList_GET_SIZE(value));
  77         if (recs == NULL) {
  78                 PyErr_NoMemory();
  79                 return -1;
  80         }
  81         for (i = 0; i < PyList_GET_SIZE(value); i++) {
  82                 bool type_correct;
  83                 PyObject *item = PyList_GET_ITEM(value, i);
  84                 type_correct = py_check_dcerpc_type(item, "samba.dcerpc.dnsp", "DnssrvRpcRecord");
  85                 if (type_correct == false) {
  86                         return -1;
  87                 }
  88                 if (talloc_reference(mem_ctx, pytalloc_get_mem_ctx(item)) == NULL) {
  89                         PyErr_NoMemory();
  90                         return -1;
  91                 }
  92                 recs[i] = *(struct dnsp_DnssrvRpcRecord *)pytalloc_get_ptr(item);
  93         }
  94         *records = recs;
  95         *num_records = PyList_GET_SIZE(value);
  96         return 0;
  97 }
  98
  99 static PyObject *py_dsdb_dns_lookup(PyObject *self,
 100                                     PyObject *args, PyObject *kwargs)
 101 {
 102         struct ldb_context *samdb;
 103         PyObject *py_ldb, *ret, *pydn;
 104         PyObject *py_dns_partition = NULL;
 105         PyObject *result = NULL;
 106         char *dns_name;
 107         TALLOC_CTX *frame;
 108         NTSTATUS status;
 109         WERROR werr;
 110         struct dns_server_zone *zones_list;
 111         struct ldb_dn *dn, *dns_partition = NULL;
 112         struct dnsp_DnssrvRpcRecord *records;
 113         uint16_t num_records;
 114         const char * const kwnames[] = { "ldb", "dns_name",
 115                                          "dns_partition", NULL };
 116
 117         if (!PyArg_ParseTupleAndKeywords(args, kwargs, "Os|O",
 118                                          discard_const_p(char *, kwnames),
 119                                          &py_ldb, &dns_name,
 120                                          &py_dns_partition)) {
 121                 return NULL;
 122         }
 123         PyErr_LDB_OR_RAISE(py_ldb, samdb);
 124
 125         if (py_dns_partition) {
 126                 PyErr_LDB_DN_OR_RAISE(py_dns_partition,
 127                                       dns_partition);
 128         }
 129
 130         frame = talloc_stackframe();
 131
 132         status = dns_common_zones(samdb, frame, dns_partition,
 133                                   &zones_list);
 134         if (!NT_STATUS_IS_OK(status)) {
 135                 talloc_free(frame);
 136                 PyErr_SetNTSTATUS(status);
 137                 return NULL;
 138         }
 139
 140         werr = dns_common_name2dn(samdb, zones_list, frame, dns_name, &dn);
 141         if (!W_ERROR_IS_OK(werr)) {
 142                 talloc_free(frame);
 143                 PyErr_SetWERROR(werr);
 144                 return NULL;
 145         }
 146
 147         werr = dns_common_lookup(samdb,
 148                                  frame,
 149                                  dn,
 150                                  &records,
 151                                  &num_records,
 152                                  NULL);
 153         if (!W_ERROR_IS_OK(werr)) {
 154                 talloc_free(frame);
 155                 PyErr_SetWERROR(werr);
 156                 return NULL;
 157         }
 158
 159         ret = py_dnsp_DnssrvRpcRecord_get_list(records, num_records);
 160         pydn = pyldb_Dn_FromDn(dn);
 161         talloc_free(frame);
 162         result = Py_BuildValue("(OO)", pydn, ret);
 163         Py_CLEAR(ret);
 164         Py_CLEAR(pydn);
 165         return result;
 166 }
 167
 168 static PyObject *py_dsdb_dns_extract(PyObject *self, PyObject *args)
 169 {
 170         struct ldb_context *samdb;
 171         PyObject *py_dns_el, *ret;
 172         PyObject *py_ldb = NULL;
 173         TALLOC_CTX *frame;
 174         WERROR werr;
 175         struct ldb_message_element *dns_el;
 176         struct dnsp_DnssrvRpcRecord *records;
 177         uint16_t num_records;
 178
 179         if (!PyArg_ParseTuple(args, "OO", &py_ldb, &py_dns_el)) {
 180                 return NULL;
 181         }
 182
 183         PyErr_LDB_OR_RAISE(py_ldb, samdb);
 184
 185         if (!py_check_dcerpc_type(py_dns_el, "ldb", "MessageElement")) {
 186                 PyErr_SetString(PyExc_TypeError,
 187                                 "ldb MessageElement object required");
 188                 return NULL;
 189         }
 190         dns_el = pyldb_MessageElement_AsMessageElement(py_dns_el);
 191
 192         frame = talloc_stackframe();
 193
 194         werr = dns_common_extract(samdb, dns_el,
 195                                   frame,
 196                                   &records,
 197                                   &num_records);
 198         if (!W_ERROR_IS_OK(werr)) {
 199                 talloc_free(frame);
 200                 PyErr_SetWERROR(werr);
 201                 return NULL;
 202         }
 203
 204         ret = py_dnsp_DnssrvRpcRecord_get_list(records, num_records);
 205         talloc_free(frame);
 206         return ret;
 207 }
 208
 209 static PyObject *py_dsdb_dns_replace(PyObject *self, PyObject *args)
 210 {
 211         struct ldb_context *samdb;
 212         PyObject *py_ldb, *py_dns_records;
 213         char *dns_name;
 214         TALLOC_CTX *frame;
 215         NTSTATUS status;
 216         WERROR werr;
 217         int ret;
 218         struct dns_server_zone *zones_list;
 219         struct ldb_dn *dn;
 220         struct dnsp_DnssrvRpcRecord *records;
 221         uint16_t num_records;
 222
 223         /*
 224          * TODO: This is a shocking abuse, but matches what the
 225          * internal DNS server does, it should be pushed into
 226          * dns_common_replace()
 227          */
 228         static const int serial = 110;
 229
 230         if (!PyArg_ParseTuple(args, "OsO", &py_ldb, &dns_name, &py_dns_records)) {
 231                 return NULL;
 232         }
 233         PyErr_LDB_OR_RAISE(py_ldb, samdb);
 234
 235         frame = talloc_stackframe();
 236
 237         status = dns_common_zones(samdb, frame, NULL, &zones_list);
 238         if (!NT_STATUS_IS_OK(status)) {
 239                 PyErr_SetNTSTATUS(status);
 240                 talloc_free(frame);
 241                 return NULL;
 242         }
 243
 244         werr = dns_common_name2dn(samdb, zones_list, frame, dns_name, &dn);
 245         if (!W_ERROR_IS_OK(werr)) {
 246                 PyErr_SetWERROR(werr);
 247                 talloc_free(frame);
 248                 return NULL;
 249         }
 250
 251         ret = py_dnsp_DnssrvRpcRecord_get_array(py_dns_records,
 252                                                 frame,
 253                                                 &records, &num_records);
 254         if (ret != 0) {
 255                 talloc_free(frame);
 256                 return NULL;
 257         }
 258
 259         werr = dns_common_replace(samdb,
 260                                   frame,
 261                                   dn,
 262                                   false, /* Not adding a record */
 263                                   serial,
 264                                   records,
 265                                   num_records);
 266         if (!W_ERROR_IS_OK(werr)) {
 267                 PyErr_SetWERROR(werr);
 268                 talloc_free(frame);
 269                 return NULL;
 270         }
 271
 272         talloc_free(frame);
 273         Py_RETURN_NONE;
 274 }
 275
 276 static PyObject *py_dsdb_dns_replace_by_dn(PyObject *self, PyObject *args)
 277 {
 278         struct ldb_context *samdb;
 279         PyObject *py_ldb, *py_dn, *py_dns_records;
 280         TALLOC_CTX *frame;
 281         WERROR werr;
 282         int ret;
 283         struct ldb_dn *dn;
 284         struct dnsp_DnssrvRpcRecord *records;
 285         uint16_t num_records;
 286
 287         /*
 288          * TODO: This is a shocking abuse, but matches what the
 289          * internal DNS server does, it should be pushed into
 290          * dns_common_replace()
 291          */
 292         static const int serial = 110;
 293
 294         if (!PyArg_ParseTuple(args, "OOO", &py_ldb, &py_dn, &py_dns_records)) {
 295                 return NULL;
 296         }
 297         PyErr_LDB_OR_RAISE(py_ldb, samdb);
 298
 299         PyErr_LDB_DN_OR_RAISE(py_dn, dn);
 300
 301         frame = talloc_stackframe();
 302
 303         ret = py_dnsp_DnssrvRpcRecord_get_array(py_dns_records,
 304                                                 frame,
 305                                                 &records, &num_records);
 306         if (ret != 0) {
 307                 talloc_free(frame);
 308                 return NULL;
 309         }
 310
 311         werr = dns_common_replace(samdb,
 312                                   frame,
 313                                   dn,
 314                                   false, /* Not adding a node */
 315                                   serial,
 316                                   records,
 317                                   num_records);
 318         if (!W_ERROR_IS_OK(werr)) {
 319                 PyErr_SetWERROR(werr);
 320                 talloc_free(frame);
 321                 return NULL;
 322         }
 323
 324         talloc_free(frame);
 325
 326         Py_RETURN_NONE;
 327 }
 328
 329
 330 static PyObject *py_dsdb_dns_records_match(PyObject *self, PyObject *args)
 331 {
 332         PyObject *py_recs[2];
 333         struct dnsp_DnssrvRpcRecord *rec1;
 334         struct dnsp_DnssrvRpcRecord *rec2;
 335         size_t i;
 336         bool type_correct;
 337         bool match;
 338
 339         if (!PyArg_ParseTuple(args, "OO", &py_recs[0], &py_recs[1])) {
 340                 return NULL;
 341         }
 342
 343         for (i = 0; i < 2; i++) {
 344                 type_correct = py_check_dcerpc_type(py_recs[i],
 345                                                     "samba.dcerpc.dnsp",
 346                                                     "DnssrvRpcRecord");
 347                 if (! type_correct) {
 348                         PyErr_SetString(PyExc_ValueError,
 349                                         "DnssrvRpcRecord expected");
 350                         return NULL;
 351                 }
 352         }
 353
 354         rec1 = (struct dnsp_DnssrvRpcRecord *)pytalloc_get_ptr(py_recs[0]);
 355         rec2 = (struct dnsp_DnssrvRpcRecord *)pytalloc_get_ptr(py_recs[1]);
 356
 357         match = dns_record_match(rec1, rec2);
 358         return PyBool_FromLong(match);
 359 }
 360
 361
 362 static PyObject *py_dsdb_dns_unix_to_dns_timestamp(PyObject *self, PyObject *args)
 363 {
 364         uint32_t timestamp;
 365         time_t t;
 366         long long lt;
 367
 368         if (!PyArg_ParseTuple(args, "L", &lt)) {
 369                 return NULL;
 370         }
 371
 372         t = lt;
 373         if (t != lt) {
 374                 /* time_t is presumably 32 bit here */
 375                 PyErr_SetString(PyExc_ValueError, "Time out of range");
 376                 return NULL;
 377         }
 378         timestamp = unix_to_dns_timestamp(t);
 379         return Py_BuildValue("k", (unsigned long) timestamp);
 380 }
 381
 382 static PyObject *py_dsdb_dns_timestamp_to_nt_time(PyObject *self, PyObject *args)
 383 {
 384         unsigned long long timestamp;
 385         NTSTATUS status;
 386         NTTIME nt;
 387         if (!PyArg_ParseTuple(args, "K", &timestamp)) {
 388                 return NULL;
 389         }
 390
 391         if (timestamp > UINT32_MAX) {
 392                 PyErr_SetString(PyExc_ValueError, "Time out of range");
 393                 return NULL;
 394         }
 395         status = dns_timestamp_to_nt_time(&nt, (uint32_t)timestamp);
 396         if (!NT_STATUS_IS_OK(status)) {
 397                 PyErr_SetString(PyExc_ValueError, "Time out of range");
 398                 return NULL;
 399         }
 400         return Py_BuildValue("L", (long long) nt);
 401 }
 402
 403
 404 static PyMethodDef py_dsdb_dns_methods[] = {
 405
 406         { "lookup", PY_DISCARD_FUNC_SIG(PyCFunction, py_dsdb_dns_lookup),
 407                 METH_VARARGS|METH_KEYWORDS,
 408                 "Get the DNS database entries for a DNS name"},
 409         { "replace", (PyCFunction)py_dsdb_dns_replace,
 410                 METH_VARARGS, "Replace the DNS database entries for a DNS name"},
 411         { "replace_by_dn", (PyCFunction)py_dsdb_dns_replace_by_dn,
 412                 METH_VARARGS, "Replace the DNS database entries for a LDB DN"},
 413         { "records_match", (PyCFunction)py_dsdb_dns_records_match,
 414           METH_VARARGS|METH_KEYWORDS,
 415           "Decide whether two records match, according to dns update rules"},
 416         { "extract", (PyCFunction)py_dsdb_dns_extract,
 417                 METH_VARARGS, "Return the DNS database entry as a python structure from an Ldb.MessageElement of type dnsRecord"},
 418         { "unix_to_dns_timestamp", (PyCFunction)py_dsdb_dns_unix_to_dns_timestamp,
 419           METH_VARARGS,
 420           "Convert a time.time() value to a dns timestamp (hours since 1601)"},
 421         { "dns_timestamp_to_nt_time", (PyCFunction)py_dsdb_dns_timestamp_to_nt_time,
 422           METH_VARARGS,
 423           "Convert a dns timestamp to an NTTIME value"},
 424         {0}
 425 };
 426
 427 static struct PyModuleDef moduledef = {
 428     PyModuleDef_HEAD_INIT,
 429     .m_name = "dsdb_dns",
 430     .m_doc = "Python bindings for the DNS objects in the directory service databases.",
 431     .m_size = -1,
 432     .m_methods = py_dsdb_dns_methods,
 433 };
 434
 435 MODULE_INIT_FUNC(dsdb_dns)
 436 {
 437         PyObject *m;
 438
 439         m = PyModule_Create(&moduledef);
 440
 441         if (m == NULL)
 442                 return NULL;
 443
 444         return m;
 445 }