source3/winbindd/winbindd_gpupdate.c

   1 /*
   2  * Unix SMB/CIFS implementation.
   3  * Group Policy Update event for winbindd
   4  * Copyright (C) David Mulder 2017
   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 #include "includes.h"
  20 #include "param/param.h"
  21 #include "param/loadparm.h"
  22 #include "winbindd.h"
  23 #include "lib/global_contexts.h"
  24
  25 /*
  26  * gpupdate_interval()
  27  * return   Random integer between 5400 and 7200, the group policy update
  28  *          interval in seconds
  29  *
  30  * Group Policy should be updated every 90 minutes in the background,
  31  * with a random offset between 0 and 30 minutes. This ensures mutiple
  32  * clients will not update at the same time.
  33  */
  34 #define GPUPDATE_INTERVAL       (90*60)
  35 #define GPUPDATE_RAND_OFFSET    (30*60)
  36 static uint32_t gpupdate_interval(void)
  37 {
  38         int rand_int_offset = generate_random() % GPUPDATE_RAND_OFFSET;
  39         return GPUPDATE_INTERVAL+rand_int_offset;
  40 }
  41
  42 struct gpupdate_state {
  43         TALLOC_CTX *ctx;
  44         struct loadparm_context *lp_ctx;
  45 };
  46
  47 static void gpupdate_callback(struct tevent_context *ev,
  48                               struct tevent_timer *tim,
  49                               struct timeval current_time,
  50                               void *private_data)
  51 {
  52         struct tevent_timer *time_event;
  53         struct timeval schedule;
  54         struct tevent_req *req = NULL;
  55         struct gpupdate_state *data =
  56                 talloc_get_type_abort(private_data, struct gpupdate_state);
  57         const char *const *gpupdate_cmd =
  58                 lpcfg_gpo_update_command(data->lp_ctx);
  59         const char *smbconf = lp_default_path();
  60
  61         /* Execute gpupdate */
  62         req = samba_runcmd_send(data->ctx, ev, timeval_zero(), 2, 0,
  63                                 gpupdate_cmd,
  64                                 "-s",
  65                                 smbconf,
  66                                 "--target=Computer",
  67                                 "--machine-pass",
  68                                 NULL);
  69         if (req == NULL) {
  70                 DEBUG(0, ("Failed to execute the gpupdate command\n"));
  71                 return;
  72         }
  73
  74         /* Schedule the next event */
  75         schedule = tevent_timeval_current_ofs(gpupdate_interval(), 0);
  76         time_event = tevent_add_timer(ev, data->ctx, schedule,
  77                                       gpupdate_callback, data);
  78         if (time_event == NULL) {
  79                 DEBUG(0, ("Failed scheduling the next gpupdate event\n"));
  80         }
  81 }
  82
  83 void gpupdate_init(void)
  84 {
  85         struct tevent_timer *time_event;
  86         struct timeval schedule;
  87         TALLOC_CTX * ctx = talloc_new(global_event_context());
  88         struct gpupdate_state *data = talloc(ctx, struct gpupdate_state);
  89         struct loadparm_context *lp_ctx =
  90                 loadparm_init_s3(NULL, loadparm_s3_helpers());
  91
  92         /*
  93          * Check if gpupdate is enabled for winbind, if not
  94          * return without scheduling any events.
  95          */
  96         if (!lpcfg_apply_group_policies(lp_ctx)) {
  97                 return;
  98         }
  99
 100         /*
 101          * Execute the first event immediately, future events
 102          * will execute on the gpupdate interval, which is every
 103          * 90 to 120 minutes (at random).
 104          */
 105         schedule = tevent_timeval_current_ofs(0, 0);
 106         data->ctx = ctx;
 107         data->lp_ctx = lp_ctx;
 108         if (data->lp_ctx == NULL) {
 109                 smb_panic("Could not load smb.conf\n");
 110         }
 111         time_event = tevent_add_timer(global_event_context(), data->ctx,
 112                                       schedule, gpupdate_callback, data);
 113         if (time_event == NULL) {
 114                 DEBUG(0, ("Failed scheduling the gpupdate event\n"));
 115         }
 116 }
 117