source4/nbt_server/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<%02x> with WINS server %s\n",
  70                          iname->name.name, iname->name.type, iname->wins_server));
  71                 nbtd_winsclient_register(iname);
  72                 return;
  73         }
  74
  75         if (!NT_STATUS_IS_OK(status)) {
  76                 DEBUG(1,("Name refresh failure with WINS for %s<%02x> - %s\n",
  77                          iname->name.name, iname->name.type, nt_errstr(status)));
  78                 talloc_free(tmp_ctx);
  79                 return;
  80         }
  81
  82         if (io.out.rcode != 0) {
  83                 DEBUG(1,("WINS server %s rejected name refresh of %s<%02x> - %s\n",
  84                          io.out.wins_server, iname->name.name, iname->name.type,
  85                          nt_errstr(nbt_rcode_to_ntstatus(io.out.rcode))));
  86                 iname->nb_flags |= NBT_NM_CONFLICT;
  87                 talloc_free(tmp_ctx);
  88                 return;
  89         }
  90
  91         DEBUG(4,("Refreshed name %s<%02x> with WINS server %s\n",
  92                  iname->name.name, iname->name.type, iname->wins_server));
  93         /* success - start a periodic name refresh */
  94         iname->nb_flags |= NBT_NM_ACTIVE;
  95         if (iname->wins_server) {
  96                 talloc_free(iname->wins_server);
  97         }
  98         iname->wins_server = talloc_steal(iname, io.out.wins_server);
  99
 100         iname->registration_time = timeval_current();
 101         event_add_timed(iname->iface->nbtsrv->task->event_ctx,
 102                         iname,
 103                         timeval_add(&iname->registration_time, iname->ttl/2, 0),
 104                         nbtd_wins_refresh,
 105                         iname);
 106
 107         talloc_free(tmp_ctx);
 108 }
 109
 110
 111 /*
 112   refresh a WINS name registration
 113 */
 114 static void nbtd_wins_refresh(struct event_context *ev, struct timed_event *te,
 115                               struct timeval t, void *private)
 116 {
 117         struct nbtd_iface_name *iname = talloc_get_type(private, struct nbtd_iface_name);
 118         struct nbtd_interface *iface = iname->iface;
 119         struct nbt_name_refresh_wins io;
 120         struct composite_context *c;
 121         TALLOC_CTX *tmp_ctx = talloc_new(iname);
 122
 123         /* setup a wins name refresh request */
 124         io.in.name            = iname->name;
 125         io.in.wins_servers    = str_list_make(tmp_ctx, iname->wins_server, NULL);
 126         io.in.addresses       = nbtd_address_list(iface, tmp_ctx);
 127         io.in.nb_flags        = iname->nb_flags;
 128         io.in.ttl             = iname->ttl;
 129
 130         c = nbt_name_refresh_wins_send(wins_socket(iface), &io);
 131         if (c == NULL) {
 132                 talloc_free(tmp_ctx);
 133                 return;
 134         }
 135         talloc_steal(c, io.in.addresses);
 136
 137         c->async.fn = nbtd_wins_refresh_handler;
 138         c->async.private = iname;
 139
 140         talloc_free(tmp_ctx);
 141 }
 142
 143
 144 /*
 145   called when a wins name register has completed
 146 */
 147 static void nbtd_wins_register_handler(struct composite_context *c)
 148 {
 149         NTSTATUS status;
 150         struct nbt_name_register_wins io;
 151         struct nbtd_iface_name *iname = talloc_get_type(c->async.private,
 152                                                         struct nbtd_iface_name);
 153         TALLOC_CTX *tmp_ctx = talloc_new(iname);
 154
 155         status = nbt_name_register_wins_recv(c, tmp_ctx, &io);
 156         if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT)) {
 157                 /* none of the WINS servers responded - try again
 158                    periodically */
 159                 int wins_retry_time = lp_parm_int(-1, "nbtd", "wins_retry", 300);
 160                 event_add_timed(iname->iface->nbtsrv->task->event_ctx,
 161                                 iname,
 162                                 timeval_current_ofs(wins_retry_time, 0),
 163                                 nbtd_wins_register_retry,
 164                                 iname);
 165                 talloc_free(tmp_ctx);
 166                 return;
 167         }
 168
 169         if (!NT_STATUS_IS_OK(status)) {
 170                 DEBUG(1,("Name register failure with WINS for %s<%02x> - %s\n",
 171                          iname->name.name, iname->name.type, nt_errstr(status)));
 172                 talloc_free(tmp_ctx);
 173                 return;
 174         }
 175
 176         if (io.out.rcode != 0) {
 177                 DEBUG(1,("WINS server %s rejected name register of %s<%02x> - %s\n",
 178                          io.out.wins_server, iname->name.name, iname->name.type,
 179                          nt_errstr(nbt_rcode_to_ntstatus(io.out.rcode))));
 180                 iname->nb_flags |= NBT_NM_CONFLICT;
 181                 talloc_free(tmp_ctx);
 182                 return;
 183         }
 184
 185         /* success - start a periodic name refresh */
 186         iname->nb_flags |= NBT_NM_ACTIVE;
 187         if (iname->wins_server) {
 188                 talloc_free(iname->wins_server);
 189         }
 190         iname->wins_server = talloc_steal(iname, io.out.wins_server);
 191
 192         iname->registration_time = timeval_current();
 193         event_add_timed(iname->iface->nbtsrv->task->event_ctx,
 194                         iname,
 195                         timeval_add(&iname->registration_time, iname->ttl/2, 0),
 196                         nbtd_wins_refresh,
 197                         iname);
 198
 199         DEBUG(3,("Registered %s<%02x> with WINS server %s\n",
 200                  iname->name.name, iname->name.type, iname->wins_server));
 201
 202         talloc_free(tmp_ctx);
 203 }
 204
 205 /*
 206   register a name with our WINS servers
 207 */
 208 void nbtd_winsclient_register(struct nbtd_iface_name *iname)
 209 {
 210         struct nbtd_interface *iface = iname->iface;
 211         struct nbt_name_register_wins io;
 212         struct composite_context *c;
 213
 214         /* setup a wins name register request */
 215         io.in.name            = iname->name;
 216         io.in.wins_servers    = lp_wins_server_list();
 217         io.in.addresses       = nbtd_address_list(iface, iname);
 218         io.in.nb_flags        = iname->nb_flags;
 219         io.in.ttl             = iname->ttl;
 220
 221         c = nbt_name_register_wins_send(wins_socket(iface), &io);
 222         if (c == NULL) {
 223                 talloc_free(io.in.addresses);
 224                 return;
 225         }
 226         talloc_steal(c, io.in.addresses);
 227
 228         c->async.fn = nbtd_wins_register_handler;
 229         c->async.private = iname;
 230 }