source/libcli/nbt/namerefresh.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    send out a name refresh request
   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 3 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, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "libcli/nbt/libnbt.h"
  24 #include "libcli/composite/composite.h"
  25 #include "lib/socket/socket.h"
  26
  27 /*
  28   send a nbt name refresh request
  29 */
  30 struct nbt_name_request *nbt_name_refresh_send(struct nbt_name_socket *nbtsock,
  31                                                struct nbt_name_refresh *io)
  32 {
  33         struct nbt_name_request *req;
  34         struct nbt_name_packet *packet;
  35         struct socket_address *dest;
  36
  37         packet = talloc_zero(nbtsock, struct nbt_name_packet);
  38         if (packet == NULL) return NULL;
  39
  40         packet->qdcount = 1;
  41         packet->arcount = 1;
  42         packet->operation = NBT_OPCODE_REFRESH;
  43         if (io->in.broadcast) {
  44                 packet->operation |= NBT_FLAG_BROADCAST;
  45         }
  46
  47         packet->questions = talloc_array(packet, struct nbt_name_question, 1);
  48         if (packet->questions == NULL) goto failed;
  49
  50         packet->questions[0].name           = io->in.name;
  51         packet->questions[0].question_type  = NBT_QTYPE_NETBIOS;
  52         packet->questions[0].question_class = NBT_QCLASS_IP;
  53
  54         packet->additional = talloc_array(packet, struct nbt_res_rec, 1);
  55         if (packet->additional == NULL) goto failed;
  56
  57         packet->additional[0].name                   = io->in.name;
  58         packet->additional[0].rr_type                = NBT_QTYPE_NETBIOS;
  59         packet->additional[0].rr_class               = NBT_QCLASS_IP;
  60         packet->additional[0].ttl                    = io->in.ttl;
  61         packet->additional[0].rdata.netbios.length   = 6;
  62         packet->additional[0].rdata.netbios.addresses = talloc_array(packet->additional,
  63                                                                      struct nbt_rdata_address, 1);
  64         if (packet->additional[0].rdata.netbios.addresses == NULL) goto failed;
  65         packet->additional[0].rdata.netbios.addresses[0].nb_flags = io->in.nb_flags;
  66         packet->additional[0].rdata.netbios.addresses[0].ipaddr =
  67                 talloc_strdup(packet->additional, io->in.address);
  68
  69         dest = socket_address_from_strings(nbtsock, nbtsock->sock->backend_name,
  70                                            io->in.dest_addr, lp_nbt_port());
  71         if (dest == NULL) goto failed;
  72         req = nbt_name_request_send(nbtsock, dest, packet,
  73                                     io->in.timeout, io->in.retries, False);
  74         if (req == NULL) goto failed;
  75
  76         talloc_free(packet);
  77         return req;
  78
  79 failed:
  80         talloc_free(packet);
  81         return NULL;
  82 }
  83
  84 /*
  85   wait for a refresh reply
  86 */
  87 NTSTATUS nbt_name_refresh_recv(struct nbt_name_request *req,
  88                                TALLOC_CTX *mem_ctx, struct nbt_name_refresh *io)
  89 {
  90         NTSTATUS status;
  91         struct nbt_name_packet *packet;
  92
  93         status = nbt_name_request_recv(req);
  94         if (!NT_STATUS_IS_OK(status) ||
  95             req->num_replies == 0) {
  96                 talloc_free(req);
  97                 return status;
  98         }
  99
 100         packet = req->replies[0].packet;
 101         io->out.reply_from = talloc_steal(mem_ctx, req->replies[0].dest->addr);
 102
 103         if (packet->ancount != 1 ||
 104             packet->answers[0].rr_type != NBT_QTYPE_NETBIOS ||
 105             packet->answers[0].rr_class != NBT_QCLASS_IP) {
 106                 talloc_free(req);
 107                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
 108         }
 109
 110         io->out.rcode = packet->operation & NBT_RCODE;
 111         io->out.name = packet->answers[0].name;
 112         if (packet->answers[0].rdata.netbios.length < 6) {
 113                 talloc_free(req);
 114                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
 115         }
 116         io->out.reply_addr = talloc_steal(mem_ctx,
 117                                           packet->answers[0].rdata.netbios.addresses[0].ipaddr);
 118         talloc_steal(mem_ctx, io->out.name.name);
 119         talloc_steal(mem_ctx, io->out.name.scope);
 120
 121         talloc_free(req);
 122
 123         return NT_STATUS_OK;
 124 }
 125
 126 /*
 127   synchronous name refresh request
 128 */
 129 NTSTATUS nbt_name_refresh(struct nbt_name_socket *nbtsock,
 130                            TALLOC_CTX *mem_ctx, struct nbt_name_refresh *io)
 131 {
 132         struct nbt_name_request *req = nbt_name_refresh_send(nbtsock, io);
 133         return nbt_name_refresh_recv(req, mem_ctx, io);
 134 }
 135
 136
 137
 138 /*
 139   a wins name refresh with multiple WINS servers and multiple
 140   addresses to refresh. Try each WINS server in turn, until we get a
 141   reply for each address
 142 */
 143 struct refresh_wins_state {
 144         struct nbt_name_socket *nbtsock;
 145         struct nbt_name_refresh *io;
 146         const char **wins_servers;
 147         const char **addresses;
 148         int address_idx;
 149         struct nbt_name_request *req;
 150 };
 151
 152
 153 /*
 154   state handler for WINS multi-homed multi-server name refresh
 155 */
 156 static void name_refresh_wins_handler(struct nbt_name_request *req)
 157 {
 158         struct composite_context *c = talloc_get_type(req->async.private,
 159                                                       struct composite_context);
 160         struct refresh_wins_state *state = talloc_get_type(c->private_data,
 161                                                             struct refresh_wins_state);
 162         NTSTATUS status;
 163
 164         status = nbt_name_refresh_recv(state->req, state, state->io);
 165         if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT)) {
 166                 /* the refresh timed out - try the next WINS server */
 167                 state->wins_servers++;
 168                 state->address_idx = 0;
 169                 if (state->wins_servers[0] == NULL) {
 170                         c->state = COMPOSITE_STATE_ERROR;
 171                         c->status = status;
 172                         goto done;
 173                 }
 174                 state->io->in.dest_addr = state->wins_servers[0];
 175                 state->io->in.address   = state->addresses[0];
 176                 state->req = nbt_name_refresh_send(state->nbtsock, state->io);
 177                 if (state->req == NULL) {
 178                         c->state = COMPOSITE_STATE_ERROR;
 179                         c->status = NT_STATUS_NO_MEMORY;
 180                 } else {
 181                         state->req->async.fn      = name_refresh_wins_handler;
 182                         state->req->async.private = c;
 183                 }
 184         } else if (!NT_STATUS_IS_OK(status)) {
 185                 c->state = COMPOSITE_STATE_ERROR;
 186                 c->status = status;
 187         } else {
 188                 if (state->io->out.rcode == 0 &&
 189                     state->addresses[state->address_idx+1] != NULL) {
 190                         /* refresh our next address */
 191                         state->io->in.address = state->addresses[++(state->address_idx)];
 192                         state->req = nbt_name_refresh_send(state->nbtsock, state->io);
 193                         if (state->req == NULL) {
 194                                 c->state = COMPOSITE_STATE_ERROR;
 195                                 c->status = NT_STATUS_NO_MEMORY;
 196                         } else {
 197                                 state->req->async.fn      = name_refresh_wins_handler;
 198                                 state->req->async.private = c;
 199                         }
 200                 } else {
 201                         c->state = COMPOSITE_STATE_DONE;
 202                         c->status = NT_STATUS_OK;
 203                 }
 204         }
 205
 206 done:
 207         if (c->state >= COMPOSITE_STATE_DONE &&
 208             c->async.fn) {
 209                 c->async.fn(c);
 210         }
 211 }
 212
 213 /*
 214   the async send call for a multi-server WINS refresh
 215 */
 216 struct composite_context *nbt_name_refresh_wins_send(struct nbt_name_socket *nbtsock,
 217                                                       struct nbt_name_refresh_wins *io)
 218 {
 219         struct composite_context *c;
 220         struct refresh_wins_state *state;
 221
 222         c = talloc_zero(nbtsock, struct composite_context);
 223         if (c == NULL) goto failed;
 224
 225         state = talloc(c, struct refresh_wins_state);
 226         if (state == NULL) goto failed;
 227
 228         state->io = talloc(state, struct nbt_name_refresh);
 229         if (state->io == NULL) goto failed;
 230
 231         state->wins_servers = str_list_copy(state, io->in.wins_servers);
 232         if (state->wins_servers == NULL ||
 233             state->wins_servers[0] == NULL) goto failed;
 234
 235         state->addresses = str_list_copy(state, io->in.addresses);
 236         if (state->addresses == NULL ||
 237             state->addresses[0] == NULL) goto failed;
 238
 239         state->io->in.name            = io->in.name;
 240         state->io->in.dest_addr       = state->wins_servers[0];
 241         state->io->in.address         = io->in.addresses[0];
 242         state->io->in.nb_flags        = io->in.nb_flags;
 243         state->io->in.broadcast       = False;
 244         state->io->in.ttl             = io->in.ttl;
 245         state->io->in.timeout         = 2;
 246         state->io->in.retries         = 2;
 247
 248         state->nbtsock     = nbtsock;
 249         state->address_idx = 0;
 250
 251         state->req = nbt_name_refresh_send(nbtsock, state->io);
 252         if (state->req == NULL) goto failed;
 253
 254         state->req->async.fn      = name_refresh_wins_handler;
 255         state->req->async.private = c;
 256
 257         c->private_data = state;
 258         c->state        = COMPOSITE_STATE_IN_PROGRESS;
 259         c->event_ctx    = nbtsock->event_ctx;
 260
 261         return c;
 262
 263 failed:
 264         talloc_free(c);
 265         return NULL;
 266 }
 267
 268 /*
 269   multi-homed WINS name refresh - recv side
 270 */
 271 NTSTATUS nbt_name_refresh_wins_recv(struct composite_context *c, TALLOC_CTX *mem_ctx,
 272                                      struct nbt_name_refresh_wins *io)
 273 {
 274         NTSTATUS status;
 275         status = composite_wait(c);
 276         if (NT_STATUS_IS_OK(status)) {
 277                 struct refresh_wins_state *state =
 278                         talloc_get_type(c->private_data, struct refresh_wins_state);
 279                 io->out.wins_server = talloc_steal(mem_ctx, state->wins_servers[0]);
 280                 io->out.rcode = state->io->out.rcode;
 281         }
 282         talloc_free(c);
 283         return status;
 284 }
 285
 286 /*
 287   multi-homed WINS refresh - sync interface
 288 */
 289 NTSTATUS nbt_name_refresh_wins(struct nbt_name_socket *nbtsock,
 290                                 TALLOC_CTX *mem_ctx,
 291                                 struct nbt_name_refresh_wins *io)
 292 {
 293         struct composite_context *c = nbt_name_refresh_wins_send(nbtsock, io);
 294         return nbt_name_refresh_wins_recv(c, mem_ctx, io);
 295 }