source4/nbt_server/wins/wins_hook.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    wins hook feature, we run a specified script
   5    which can then do some custom actions
   6
   7    Copyright (C) Stefan Metzmacher      2005
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "nbt_server/nbt_server.h"
  25 #include "nbt_server/wins/winsdb.h"
  26 #include "system/filesys.h"
  27
  28 static const char *wins_hook_action_string(enum wins_hook_action action)
  29 {
  30         switch (action) {
  31         case WINS_HOOK_ADD:     return "add";
  32         case WINS_HOOK_MODIFY:  return "refresh";
  33         case WINS_HOOK_DELETE:  return "delete";
  34         }
  35
  36         return "unknown";
  37 }
  38
  39 void wins_hook(struct winsdb_handle *h, const struct winsdb_record *rec,
  40                enum wins_hook_action action, const char *wins_hook_script)
  41 {
  42         uint32_t i, length;
  43         int child;
  44         char *cmd = NULL;
  45         TALLOC_CTX *tmp_mem = NULL;
  46
  47         if (!wins_hook_script || !wins_hook_script[0]) return;
  48
  49         tmp_mem = talloc_new(h);
  50         if (!tmp_mem) goto failed;
  51
  52         length = winsdb_addr_list_length(rec->addresses);
  53
  54         if (action == WINS_HOOK_MODIFY && length < 1) {
  55                 action = WINS_HOOK_DELETE;
  56         }
  57
  58         cmd = talloc_asprintf(tmp_mem,
  59                               "%s %s %s %02x %ld",
  60                               wins_hook_script,
  61                               wins_hook_action_string(action),
  62                               rec->name->name,
  63                               rec->name->type,
  64                               rec->expire_time);
  65         if (!cmd) goto failed;
  66
  67         for (i=0; rec->addresses[i]; i++) {
  68                 cmd = talloc_asprintf_append_buffer(cmd, " %s", rec->addresses[i]->address);
  69                 if (!cmd) goto failed;
  70         }
  71
  72         DEBUG(10,("call wins hook '%s'\n", cmd));
  73
  74         /* signal handling in posix really sucks - doing this in a library
  75            affects the whole app, but what else to do?? */
  76         signal(SIGCHLD, SIG_IGN);
  77
  78         child = fork();
  79         if (child == (pid_t)-1) {
  80                 goto failed;
  81         }
  82
  83         if (child == 0) {
  84 /* TODO: close file handles */
  85                 execl("/bin/sh", "sh", "-c", cmd, NULL);
  86                 _exit(0);
  87         }
  88
  89         talloc_free(tmp_mem);
  90         return;
  91 failed:
  92         talloc_free(tmp_mem);
  93         DEBUG(0,("FAILED: calling wins hook '%s'\n", wins_hook_script));
  94 }