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 "includes.h"
  24 #include <pyldb.h>
  25 #include <pytalloc.h>
  26 #include "dns_server/dnsserver_common.h"
  27 #include "dsdb/samdb/samdb.h"
  28 #include "dsdb/common/util.h"
  29 #include "librpc/gen_ndr/ndr_dnsp.h"
  30 #include "librpc/rpc/pyrpc_util.h"
  31
  32 /* FIXME: These should be in a header file somewhere */
  33 #define PyErr_LDB_OR_RAISE(py_ldb, ldb) \
  34         if (!py_check_dcerpc_type(py_ldb, "ldb", "Ldb")) { \
  35                 PyErr_SetString(py_ldb_get_exception(), "Ldb connection object required"); \
  36                 return NULL; \
  37         } \
  38         ldb = pyldb_Ldb_AsLdbContext(py_ldb);
  39
  40 #define PyErr_LDB_DN_OR_RAISE(py_ldb_dn, dn) \
  41         if (!py_check_dcerpc_type(py_ldb_dn, "ldb", "Dn")) { \
  42                 PyErr_SetString(py_ldb_get_exception(), "ldb Dn object required"); \
  43                 return NULL; \
  44         } \
  45         dn = pyldb_Dn_AsDn(py_ldb_dn);
  46
  47 static PyObject *py_ldb_get_exception(void)
  48 {
  49         PyObject *mod = PyImport_ImportModule("ldb");
  50         if (mod == NULL)
  51                 return NULL;
  52
  53         return PyObject_GetAttrString(mod, "LdbError");
  54 }
  55
  56 static PyObject *py_dnsp_DnssrvRpcRecord_get_list(struct dnsp_DnssrvRpcRecord *records,
  57                                                   uint16_t num_records)
  58 {
  59         PyObject *py_dns_list;
  60         int i;
  61         py_dns_list = PyList_New(num_records);
  62         if (py_dns_list == NULL) {
  63                 return NULL;
  64         }
  65         for (i = 0; i < num_records; i++) {
  66                 PyObject *py_dns_record;
  67                 py_dns_record = py_return_ndr_struct("samba.dcerpc.dnsp", "DnssrvRpcRecord", records, &records[i]);
  68                 PyList_SetItem(py_dns_list, i, py_dns_record);
  69         }
  70         return py_dns_list;
  71 }
  72
  73 static int py_dnsp_DnssrvRpcRecord_get_array(PyObject *value,
  74                                              TALLOC_CTX *mem_ctx,
  75                                              struct dnsp_DnssrvRpcRecord **records,
  76                                              uint16_t *num_records)
  77 {
  78         int i;
  79         struct dnsp_DnssrvRpcRecord *recs;
  80         PY_CHECK_TYPE(&PyList_Type, value, return -1;);
  81         recs = talloc_array(mem_ctx, struct dnsp_DnssrvRpcRecord,
  82                             PyList_GET_SIZE(value));
  83         if (recs == NULL) {
  84                 PyErr_NoMemory();
  85                 return -1;
  86         }
  87         for (i = 0; i < PyList_GET_SIZE(value); i++) {
  88                 bool type_correct;
  89                 PyObject *item = PyList_GET_ITEM(value, i);
  90                 type_correct = py_check_dcerpc_type(item, "samba.dcerpc.dnsp", "DnssrvRpcRecord");
  91                 if (type_correct == false) {
  92                         return -1;
  93                 }
  94                 if (talloc_reference(mem_ctx, pytalloc_get_mem_ctx(item)) == NULL) {
  95                         PyErr_NoMemory();
  96                         return -1;
  97                 }
  98                 recs[i] = *(struct dnsp_DnssrvRpcRecord *)pytalloc_get_ptr(item);
  99         }
 100         *records = recs;
 101         *num_records = PyList_GET_SIZE(value);
 102         return 0;
 103 }
 104
 105 static PyObject *py_dsdb_dns_lookup(PyObject *self, PyObject *args)
 106 {
 107         struct ldb_context *samdb;
 108         PyObject *py_ldb;
 109         char *dns_name;
 110         TALLOC_CTX *frame;
 111         NTSTATUS status;
 112         WERROR werr;
 113         struct dns_server_zone *zones_list;
 114         struct ldb_dn *dn;
 115         struct dnsp_DnssrvRpcRecord *records;
 116         uint16_t num_records;
 117
 118         if (!PyArg_ParseTuple(args, "Os", &py_ldb, &dns_name)) {
 119                 return NULL;
 120         }
 121         PyErr_LDB_OR_RAISE(py_ldb, samdb);
 122
 123         frame = talloc_stackframe();
 124
 125         status = dns_common_zones(samdb, frame, &zones_list);
 126         if (!NT_STATUS_IS_OK(status)) {
 127                 PyErr_SetNTSTATUS(status);
 128                 return NULL;
 129         }
 130
 131         werr = dns_common_name2dn(samdb, zones_list, frame, dns_name, &dn);
 132         if (!W_ERROR_IS_OK(werr)) {
 133                 PyErr_SetWERROR(werr);
 134                 return NULL;
 135         }
 136
 137         werr = dns_common_lookup(samdb,
 138                                  frame,
 139                                  dn,
 140                                  &records,
 141                                  &num_records,
 142                                  NULL);
 143         if (!W_ERROR_IS_OK(werr)) {
 144                 PyErr_SetWERROR(werr);
 145                 return NULL;
 146         }
 147
 148         return py_dnsp_DnssrvRpcRecord_get_list(records, num_records);
 149 }
 150
 151 static PyObject *py_dsdb_dns_extract(PyObject *self, PyObject *args)
 152 {
 153         PyObject *py_dns_el;
 154         TALLOC_CTX *frame;
 155         WERROR werr;
 156         struct ldb_message_element *dns_el;
 157         struct dnsp_DnssrvRpcRecord *records;
 158         uint16_t num_records;
 159
 160         if (!PyArg_ParseTuple(args, "O", &py_dns_el)) {
 161                 return NULL;
 162         }
 163
 164         if (!py_check_dcerpc_type(py_dns_el, "ldb", "MessageElement")) {
 165                 PyErr_SetString(py_ldb_get_exception(),
 166                                 "ldb MessageElement object required");
 167                 return NULL;
 168         }
 169         dns_el = pyldb_MessageElement_AsMessageElement(py_dns_el);
 170
 171         frame = talloc_stackframe();
 172
 173         werr = dns_common_extract(dns_el,
 174                                   frame,
 175                                   &records,
 176                                   &num_records);
 177         if (!W_ERROR_IS_OK(werr)) {
 178                 PyErr_SetWERROR(werr);
 179                 return NULL;
 180         }
 181
 182         return py_dnsp_DnssrvRpcRecord_get_list(records, num_records);
 183 }
 184
 185 static PyObject *py_dsdb_dns_replace(PyObject *self, PyObject *args)
 186 {
 187         struct ldb_context *samdb;
 188         PyObject *py_ldb, *py_dns_records;
 189         char *dns_name;
 190         TALLOC_CTX *frame;
 191         NTSTATUS status;
 192         WERROR werr;
 193         int ret;
 194         struct dns_server_zone *zones_list;
 195         struct ldb_dn *dn;
 196         struct dnsp_DnssrvRpcRecord *records;
 197         uint16_t num_records;
 198
 199         /*
 200          * TODO: This is a shocking abuse, but matches what the
 201          * internal DNS server does, it should be pushed into
 202          * dns_common_replace()
 203          */
 204         static const int serial = 110;
 205
 206         if (!PyArg_ParseTuple(args, "OsO", &py_ldb, &dns_name, &py_dns_records)) {
 207                 return NULL;
 208         }
 209         PyErr_LDB_OR_RAISE(py_ldb, samdb);
 210
 211         frame = talloc_stackframe();
 212
 213         status = dns_common_zones(samdb, frame, &zones_list);
 214         if (!NT_STATUS_IS_OK(status)) {
 215                 PyErr_SetNTSTATUS(status);
 216                 return NULL;
 217         }
 218
 219         werr = dns_common_name2dn(samdb, zones_list, frame, dns_name, &dn);
 220         if (!W_ERROR_IS_OK(werr)) {
 221                 PyErr_SetWERROR(werr);
 222                 return NULL;
 223         }
 224
 225         ret = py_dnsp_DnssrvRpcRecord_get_array(py_dns_records,
 226                                                 frame,
 227                                                 &records, &num_records);
 228         if (ret != 0) {
 229                 return NULL;
 230         }
 231
 232         werr = dns_common_replace(samdb,
 233                                   frame,
 234                                   dn,
 235                                   false, /* Not adding a record */
 236                                   serial,
 237                                   records,
 238                                   num_records);
 239         if (!W_ERROR_IS_OK(werr)) {
 240                 PyErr_SetWERROR(werr);
 241                 return NULL;
 242         }
 243
 244         Py_RETURN_NONE;
 245 }
 246
 247 static PyObject *py_dsdb_dns_replace_by_dn(PyObject *self, PyObject *args)
 248 {
 249         struct ldb_context *samdb;
 250         PyObject *py_ldb, *py_dn, *py_dns_records;
 251         TALLOC_CTX *frame;
 252         WERROR werr;
 253         int ret;
 254         struct ldb_dn *dn;
 255         struct dnsp_DnssrvRpcRecord *records;
 256         uint16_t num_records;
 257
 258         /*
 259          * TODO: This is a shocking abuse, but matches what the
 260          * internal DNS server does, it should be pushed into
 261          * dns_common_replace()
 262          */
 263         static const int serial = 110;
 264
 265         if (!PyArg_ParseTuple(args, "OOO", &py_ldb, &py_dn, &py_dns_records)) {
 266                 return NULL;
 267         }
 268         PyErr_LDB_OR_RAISE(py_ldb, samdb);
 269
 270         PyErr_LDB_DN_OR_RAISE(py_dn, dn);
 271
 272         frame = talloc_stackframe();
 273
 274         ret = py_dnsp_DnssrvRpcRecord_get_array(py_dns_records,
 275                                                 frame,
 276                                                 &records, &num_records);
 277         if (ret != 0) {
 278                 return NULL;
 279         }
 280
 281         werr = dns_common_replace(samdb,
 282                                   frame,
 283                                   dn,
 284                                   false, /* Not adding a record */
 285                                   serial,
 286                                   records,
 287                                   num_records);
 288         if (!W_ERROR_IS_OK(werr)) {
 289                 PyErr_SetWERROR(werr);
 290                 return NULL;
 291         }
 292
 293         Py_RETURN_NONE;
 294 }
 295
 296 static PyMethodDef py_dsdb_dns_methods[] = {
 297
 298         { "lookup", (PyCFunction)py_dsdb_dns_lookup,
 299                 METH_VARARGS, "Get the DNS database entries for a DNS name"},
 300         { "replace", (PyCFunction)py_dsdb_dns_replace,
 301                 METH_VARARGS, "Replace the DNS database entries for a DNS name"},
 302         { "replace_by_dn", (PyCFunction)py_dsdb_dns_replace_by_dn,
 303                 METH_VARARGS, "Replace the DNS database entries for a LDB DN"},
 304         { "extract", (PyCFunction)py_dsdb_dns_extract,
 305                 METH_VARARGS, "Return the DNS database entry as a python structure from an Ldb.MessageElement of type dnsRecord"},
 306         { NULL }
 307 };
 308
 309 void initdsdb_dns(void);
 310
 311 void initdsdb_dns(void)
 312 {
 313         PyObject *m;
 314
 315         m = Py_InitModule3("dsdb_dns", py_dsdb_dns_methods,
 316                            "Python bindings for the DNS objects in the directory service databases.");
 317         if (m == NULL)
 318                 return;
 319 }