source4/wrepl_server/wrepl_out_push.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    WINS Replication server
   5
   6    Copyright (C) Stefan Metzmacher      2005
   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 2 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, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 #include "includes.h"
  24 #include "librpc/gen_ndr/ndr_winsrepl.h"
  25 #include "wrepl_server/wrepl_server.h"
  26 #include "libcli/composite/composite.h"
  27 #include "wrepl_server/wrepl_out_helpers.h"
  28 #include "nbt_server/wins/winsdb.h"
  29
  30 static void wreplsrv_out_partner_push(struct wreplsrv_partner *partner, BOOL propagate);
  31
  32 static void wreplsrv_push_handler_creq(struct composite_context *creq)
  33 {
  34         struct wreplsrv_partner *partner = talloc_get_type(creq->async.private_data, struct wreplsrv_partner);
  35         struct wreplsrv_push_notify_io *old_notify_io;
  36
  37         partner->push.last_status = wreplsrv_push_notify_recv(partner->push.creq);
  38         partner->push.creq = NULL;
  39
  40         old_notify_io = partner->push.notify_io;
  41         partner->push.notify_io = NULL;
  42
  43         if (NT_STATUS_IS_OK(partner->push.last_status)) {
  44                 partner->push.error_count = 0;
  45                 DEBUG(2,("wreplsrv_push_notify(%s): %s\n",
  46                          partner->address, nt_errstr(partner->push.last_status)));
  47                 goto done;
  48         }
  49
  50         partner->push.error_count++;
  51
  52         if (partner->push.error_count > 1) {
  53                 DEBUG(1,("wreplsrv_push_notify(%s): %s: error_count: %u: giving up\n",
  54                          partner->address, nt_errstr(partner->push.last_status),
  55                          partner->push.error_count));
  56                 goto done;
  57         }
  58
  59         DEBUG(1,("wreplsrv_push_notify(%s): %s: error_count: %u: retry\n",
  60                  partner->address, nt_errstr(partner->push.last_status),
  61                  partner->push.error_count));
  62         wreplsrv_out_partner_push(partner, old_notify_io->in.propagate);
  63 done:
  64         talloc_free(old_notify_io);
  65 }
  66
  67 static void wreplsrv_out_partner_push(struct wreplsrv_partner *partner, BOOL propagate)
  68 {
  69         /* a push for this partner is currently in progress, so we're done */
  70         if (partner->push.creq) return;
  71
  72         /* now prepare the push notify */
  73         partner->push.notify_io = talloc(partner, struct wreplsrv_push_notify_io);
  74         if (!partner->push.notify_io) {
  75                 goto nomem;
  76         }
  77
  78         partner->push.notify_io->in.partner     = partner;
  79         partner->push.notify_io->in.inform      = partner->push.use_inform;
  80         partner->push.notify_io->in.propagate   = propagate;
  81         partner->push.creq = wreplsrv_push_notify_send(partner->push.notify_io, partner->push.notify_io);
  82         if (!partner->push.creq) {
  83                 DEBUG(1,("wreplsrv_push_notify_send(%s) failed nomem?\n",
  84                          partner->address));
  85                 goto nomem;
  86         }
  87
  88         partner->push.creq->async.fn            = wreplsrv_push_handler_creq;
  89         partner->push.creq->async.private_data  = partner;
  90
  91         return;
  92 nomem:
  93         talloc_free(partner->push.notify_io);
  94         partner->push.notify_io = NULL;
  95         DEBUG(1,("wreplsrv_out_partner_push(%s,%u) failed nomem? (ignoring)\n",
  96                  partner->address, propagate));
  97         return;
  98 }
  99
 100 static uint32_t wreplsrv_calc_change_count(struct wreplsrv_partner *partner, uint64_t seqnumber)
 101 {
 102         uint64_t tmp_diff = UINT32_MAX;
 103
 104         /* catch an overflow */
 105         if (partner->push.seqnumber > seqnumber) {
 106                 goto done;
 107         }
 108
 109         tmp_diff = seqnumber - partner->push.seqnumber;
 110
 111         if (tmp_diff > UINT32_MAX) {
 112                 tmp_diff = UINT32_MAX;
 113                 goto done;
 114         }
 115
 116 done:
 117         partner->push.seqnumber = seqnumber;
 118         return (uint32_t)(tmp_diff & UINT32_MAX);
 119 }
 120
 121 NTSTATUS wreplsrv_out_push_run(struct wreplsrv_service *service)
 122 {
 123         struct wreplsrv_partner *partner;
 124         uint64_t seqnumber;
 125         uint32_t change_count;
 126
 127         seqnumber = winsdb_get_seqnumber(service->wins_db);
 128
 129         for (partner = service->partners; partner; partner = partner->next) {
 130                 /* if it's not a push partner, go to the next partner */
 131                 if (!(partner->type & WINSREPL_PARTNER_PUSH)) continue;
 132
 133                 /* if push notifies are disabled for this partner, go to the next partner */
 134                 if (partner->push.change_count == 0) continue;
 135
 136                 /* get the actual change count for the partner */
 137                 change_count = wreplsrv_calc_change_count(partner, seqnumber);
 138
 139                 /* if the configured change count isn't reached, go to the next partner */
 140                 if (change_count < partner->push.change_count) continue;
 141
 142                 wreplsrv_out_partner_push(partner, False);
 143         }
 144
 145         return NT_STATUS_OK;
 146 }