source/nbt_server/wins/winsclient.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    wins client name registration and refresh
   5
   6    Copyright (C) Andrew Tridgell        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 "nbt_server/nbt_server.h"
  25 #include "libcli/raw/libcliraw.h"
  26 #include "libcli/composite/composite.h"
  27 #include "lib/events/events.h"
  28 #include "smbd/service_task.h"
  29
  30
  31 /* we send WINS client requests using our primary network interface
  32 */
  33 static struct nbt_name_socket *wins_socket(struct nbtd_interface *iface)
  34 {
  35         struct nbtd_server *nbtsrv = iface->nbtsrv;
  36         return nbtsrv->interfaces->nbtsock;
  37 }
  38
  39
  40 static void nbtd_wins_refresh(struct event_context *ev, struct timed_event *te,
  41                               struct timeval t, void *private);
  42
  43 /*
  44   retry a WINS name registration
  45 */
  46 static void nbtd_wins_register_retry(struct event_context *ev, struct timed_event *te,
  47                                      struct timeval t, void *private)
  48 {
  49         struct nbtd_iface_name *iname = talloc_get_type(private, struct nbtd_iface_name);
  50         nbtd_winsclient_register(iname);
  51 }
  52
  53
  54 /*
  55   called when a wins name refresh has completed
  56 */
  57 static void nbtd_wins_refresh_handler(struct composite_context *c)
  58 {
  59         NTSTATUS status;
  60         struct nbt_name_refresh_wins io;
  61         struct nbtd_iface_name *iname = talloc_get_type(c->async.private,
  62                                                         struct nbtd_iface_name);
  63         TALLOC_CTX *tmp_ctx = talloc_new(iname);
  64
  65         status = nbt_name_refresh_wins_recv(c, tmp_ctx, &io);
  66         if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT)) {
  67                 /* our WINS server is dead - start registration over
  68                    from scratch */
  69                 DEBUG(2,("Failed to refresh %s with WINS server %s\n",
  70                          nbt_name_string(tmp_ctx, &iname->name), iname->wins_server));
  71                 talloc_free(tmp_ctx);
  72                 nbtd_winsclient_register(iname);
  73                 return;
  74         }
  75
  76         if (!NT_STATUS_IS_OK(status)) {
  77                 DEBUG(1,("Name refresh failure with WINS for %s - %s\n",
  78                          nbt_name_string(tmp_ctx, &iname->name), nt_errstr(status)));
  79                 talloc_free(tmp_ctx);
  80                 return;
  81         }
  82
  83         if (io.out.rcode != 0) {
  84                 DEBUG(1,("WINS server %s rejected name refresh of %s - %s\n",
  85                          io.out.wins_server, nbt_name_string(tmp_ctx, &iname->name),
  86                          nt_errstr(nbt_rcode_to_ntstatus(io.out.rcode))));
  87                 iname->nb_flags |= NBT_NM_CONFLICT;
  88                 talloc_free(tmp_ctx);
  89                 return;
  90         }
  91
  92         DEBUG(4,("Refreshed name %s with WINS server %s\n",
  93                  nbt_name_string(tmp_ctx, &iname->name), iname->wins_server));
  94         /* success - start a periodic name refresh */
  95         iname->nb_flags |= NBT_NM_ACTIVE;
  96         if (iname->wins_server) {
  97                 talloc_free(iname->wins_server);
  98         }
  99         iname->wins_server = talloc_steal(iname, io.out.wins_server);
 100
 101         iname->registration_time = timeval_current();
 102         event_add_timed(iname->iface->nbtsrv->task->event_ctx,
 103                         iname,
 104                         timeval_add(&iname->registration_time, iname->ttl/2, 0),
 105                         nbtd_wins_refresh,
 106                         iname);
 107
 108         talloc_free(tmp_ctx);
 109 }
 110
 111
 112 /*
 113   refresh a WINS name registration
 114 */
 115 static void nbtd_wins_refresh(struct event_context *ev, struct timed_event *te,
 116                               struct timeval t, void *private)
 117 {
 118         struct nbtd_iface_name *iname = talloc_get_type(private, struct nbtd_iface_name);
 119         struct nbtd_interface *iface = iname->iface;
 120         struct nbt_name_refresh_wins io;
 121         struct composite_context *c;
 122         TALLOC_CTX *tmp_ctx = talloc_new(iname);
 123
 124         /* setup a wins name refresh request */
 125         io.in.name            = iname->name;
 126         io.in.wins_servers    = str_list_make(tmp_ctx, iname->wins_server, NULL);
 127         io.in.addresses       = nbtd_address_list(iface, tmp_ctx);
 128         io.in.nb_flags        = iname->nb_flags;
 129         io.in.ttl             = iname->ttl;
 130
 131         c = nbt_name_refresh_wins_send(wins_socket(iface), &io);
 132         if (c == NULL) {
 133                 talloc_free(tmp_ctx);
 134                 return;
 135         }
 136         talloc_steal(c, io.in.addresses);
 137
 138         c->async.fn = nbtd_wins_refresh_handler;
 139         c->async.private = iname;
 140
 141         talloc_free(tmp_ctx);
 142 }
 143
 144
 145 /*
 146   called when a wins name register has completed
 147 */
 148 static void nbtd_wins_register_handler(struct composite_context *c)
 149 {
 150         NTSTATUS status;
 151         struct nbt_name_register_wins io;
 152         struct nbtd_iface_name *iname = talloc_get_type(c->async.private,
 153                                                         struct nbtd_iface_name);
 154         TALLOC_CTX *tmp_ctx = talloc_new(iname);
 155
 156         status = nbt_name_register_wins_recv(c, tmp_ctx, &io);
 157         if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT)) {
 158                 /* none of the WINS servers responded - try again
 159                    periodically */
 160                 int wins_retry_time = lp_parm_int(-1, "nbtd", "wins_retry", 300);
 161                 event_add_timed(iname->iface->nbtsrv->task->event_ctx,
 162                                 iname,
 163                                 timeval_current_ofs(wins_retry_time, 0),
 164                                 nbtd_wins_register_retry,
 165                                 iname);
 166                 talloc_free(tmp_ctx);
 167                 return;
 168         }
 169
 170         if (!NT_STATUS_IS_OK(status)) {
 171                 DEBUG(1,("Name register failure with WINS for %s - %s\n",
 172                          nbt_name_string(tmp_ctx, &iname->name), nt_errstr(status)));
 173                 talloc_free(tmp_ctx);
 174                 return;
 175         }
 176
 177         if (io.out.rcode != 0) {
 178                 DEBUG(1,("WINS server %s rejected name register of %s - %s\n",
 179                          io.out.wins_server, nbt_name_string(tmp_ctx, &iname->name),
 180                          nt_errstr(nbt_rcode_to_ntstatus(io.out.rcode))));
 181                 iname->nb_flags |= NBT_NM_CONFLICT;
 182                 talloc_free(tmp_ctx);
 183                 return;
 184         }
 185
 186         /* success - start a periodic name refresh */
 187         iname->nb_flags |= NBT_NM_ACTIVE;
 188         if (iname->wins_server) {
 189                 talloc_free(iname->wins_server);
 190         }
 191         iname->wins_server = talloc_steal(iname, io.out.wins_server);
 192
 193         iname->registration_time = timeval_current();
 194         event_add_timed(iname->iface->nbtsrv->task->event_ctx,
 195                         iname,
 196                         timeval_add(&iname->registration_time, iname->ttl/2, 0),
 197                         nbtd_wins_refresh,
 198                         iname);
 199
 200         DEBUG(3,("Registered %s with WINS server %s\n",
 201                  nbt_name_string(tmp_ctx, &iname->name), iname->wins_server));
 202
 203         talloc_free(tmp_ctx);
 204 }
 205
 206 /*
 207   register a name with our WINS servers
 208 */
 209 void nbtd_winsclient_register(struct nbtd_iface_name *iname)
 210 {
 211         struct nbtd_interface *iface = iname->iface;
 212         struct nbt_name_register_wins io;
 213         struct composite_context *c;
 214
 215         /* setup a wins name register request */
 216         io.in.name            = iname->name;
 217         io.in.wins_servers    = lp_wins_server_list();
 218         io.in.addresses       = nbtd_address_list(iface, iname);
 219         io.in.nb_flags        = iname->nb_flags;
 220         io.in.ttl             = iname->ttl;
 221
 222         c = nbt_name_register_wins_send(wins_socket(iface), &io);
 223         if (c == NULL) {
 224                 talloc_free(io.in.addresses);
 225                 return;
 226         }
 227         talloc_steal(c, io.in.addresses);
 228
 229         c->async.fn = nbtd_wins_register_handler;
 230         c->async.private = iname;
 231 }