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 <tevent.h>
  24 #include "../libcli/nbt/libnbt.h"
  25 #include "../libcli/nbt/nbt_proto.h"
  26 #include "lib/socket/socket.h"
  27 #include "lib/util/tevent_ntstatus.h"
  28
  29 /*
  30   send a nbt name refresh request
  31 */
  32 struct nbt_name_request *nbt_name_refresh_send(struct nbt_name_socket *nbtsock,
  33                                                struct nbt_name_refresh *io)
  34 {
  35         struct nbt_name_request *req;
  36         struct nbt_name_packet *packet;
  37         struct socket_address *dest;
  38
  39         packet = talloc_zero(nbtsock, struct nbt_name_packet);
  40         if (packet == NULL) return NULL;
  41
  42         packet->qdcount = 1;
  43         packet->arcount = 1;
  44         packet->operation = NBT_OPCODE_REFRESH;
  45         if (io->in.broadcast) {
  46                 packet->operation |= NBT_FLAG_BROADCAST;
  47         }
  48
  49         packet->questions = talloc_array(packet, struct nbt_name_question, 1);
  50         if (packet->questions == NULL) goto failed;
  51
  52         packet->questions[0].name           = io->in.name;
  53         packet->questions[0].question_type  = NBT_QTYPE_NETBIOS;
  54         packet->questions[0].question_class = NBT_QCLASS_IP;
  55
  56         packet->additional = talloc_array(packet, struct nbt_res_rec, 1);
  57         if (packet->additional == NULL) goto failed;
  58
  59         packet->additional[0].name                   = io->in.name;
  60         packet->additional[0].rr_type                = NBT_QTYPE_NETBIOS;
  61         packet->additional[0].rr_class               = NBT_QCLASS_IP;
  62         packet->additional[0].ttl                    = io->in.ttl;
  63         packet->additional[0].rdata.netbios.length   = 6;
  64         packet->additional[0].rdata.netbios.addresses = talloc_array(packet->additional,
  65                                                                      struct nbt_rdata_address, 1);
  66         if (packet->additional[0].rdata.netbios.addresses == NULL) goto failed;
  67         packet->additional[0].rdata.netbios.addresses[0].nb_flags = io->in.nb_flags;
  68         packet->additional[0].rdata.netbios.addresses[0].ipaddr =
  69                 talloc_strdup(packet->additional, io->in.address);
  70
  71         dest = socket_address_from_strings(nbtsock,
  72                                            nbtsock->sock->backend_name,
  73                                            io->in.dest_addr, io->in.dest_port);
  74         if (dest == NULL) goto failed;
  75         req = nbt_name_request_send(nbtsock, dest, packet,
  76                                     io->in.timeout, io->in.retries, false);
  77         if (req == NULL) goto failed;
  78
  79         talloc_free(packet);
  80         return req;
  81
  82 failed:
  83         talloc_free(packet);
  84         return NULL;
  85 }
  86
  87 /*
  88   wait for a refresh reply
  89 */
  90 _PUBLIC_ NTSTATUS nbt_name_refresh_recv(struct nbt_name_request *req,
  91                                TALLOC_CTX *mem_ctx, struct nbt_name_refresh *io)
  92 {
  93         NTSTATUS status;
  94         struct nbt_name_packet *packet;
  95
  96         status = nbt_name_request_recv(req);
  97         if (!NT_STATUS_IS_OK(status) ||
  98             req->num_replies == 0) {
  99                 talloc_free(req);
 100                 return status;
 101         }
 102
 103         packet = req->replies[0].packet;
 104         io->out.reply_from = talloc_steal(mem_ctx, req->replies[0].dest->addr);
 105
 106         if (packet->ancount != 1 ||
 107             packet->answers[0].rr_type != NBT_QTYPE_NETBIOS ||
 108             packet->answers[0].rr_class != NBT_QCLASS_IP) {
 109                 talloc_free(req);
 110                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
 111         }
 112
 113         io->out.rcode = packet->operation & NBT_RCODE;
 114         io->out.name = packet->answers[0].name;
 115         if (packet->answers[0].rdata.netbios.length < 6) {
 116                 talloc_free(req);
 117                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
 118         }
 119         io->out.reply_addr = talloc_steal(mem_ctx,
 120                                           packet->answers[0].rdata.netbios.addresses[0].ipaddr);
 121         talloc_steal(mem_ctx, io->out.name.name);
 122         talloc_steal(mem_ctx, io->out.name.scope);
 123
 124         talloc_free(req);
 125
 126         return NT_STATUS_OK;
 127 }
 128
 129 /*
 130   synchronous name refresh request
 131 */
 132 _PUBLIC_ NTSTATUS nbt_name_refresh(struct nbt_name_socket *nbtsock,
 133                            TALLOC_CTX *mem_ctx, struct nbt_name_refresh *io)
 134 {
 135         struct nbt_name_request *req = nbt_name_refresh_send(nbtsock, io);
 136         return nbt_name_refresh_recv(req, mem_ctx, io);
 137 }
 138
 139
 140
 141 /**
 142   a wins name refresh with multiple WINS servers and multiple
 143   addresses to refresh. Try each WINS server in turn, until we get a
 144   reply for each address
 145 */
 146 struct nbt_name_refresh_wins_state {
 147         struct nbt_name_socket *nbtsock;
 148         struct nbt_name_refresh *io;
 149         char **wins_servers;
 150         uint16_t wins_port;
 151         char **addresses;
 152         int address_idx;
 153 };
 154
 155 static void nbt_name_refresh_wins_handler(struct nbt_name_request *subreq);
 156
 157 /**
 158   the async send call for a multi-server WINS refresh
 159 */
 160 _PUBLIC_ struct tevent_req *nbt_name_refresh_wins_send(TALLOC_CTX *mem_ctx,
 161                                                 struct tevent_context *ev,
 162                                                 struct nbt_name_socket *nbtsock,
 163                                                 struct nbt_name_refresh_wins *io)
 164 {
 165         struct tevent_req *req;
 166         struct nbt_name_refresh_wins_state *state;
 167         struct nbt_name_request *subreq;
 168
 169         req = tevent_req_create(mem_ctx, &state,
 170                                 struct nbt_name_refresh_wins_state);
 171         if (req == NULL) {
 172                 return NULL;
 173         }
 174
 175         state->io = talloc(state, struct nbt_name_refresh);
 176         if (tevent_req_nomem(state->io, req)) {
 177                 return tevent_req_post(req, ev);
 178         }
 179
 180         if (io->in.wins_servers == NULL) {
 181                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 182                 return tevent_req_post(req, ev);
 183         }
 184
 185         if (io->in.wins_servers[0] == NULL) {
 186                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 187                 return tevent_req_post(req, ev);
 188         }
 189
 190         if (io->in.addresses == NULL) {
 191                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 192                 return tevent_req_post(req, ev);
 193         }
 194
 195         if (io->in.addresses[0] == NULL) {
 196                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
 197                 return tevent_req_post(req, ev);
 198         }
 199
 200         state->wins_port = io->in.wins_port;
 201         state->wins_servers = str_list_copy(state, io->in.wins_servers);
 202         if (tevent_req_nomem(state->wins_servers, req)) {
 203                 return tevent_req_post(req, ev);
 204         }
 205
 206         state->addresses = str_list_copy(state, io->in.addresses);
 207         if (tevent_req_nomem(state->addresses, req)) {
 208                 return tevent_req_post(req, ev);
 209         }
 210
 211         state->io->in.name            = io->in.name;
 212         state->io->in.dest_addr       = state->wins_servers[0];
 213         state->io->in.dest_port       = state->wins_port;
 214         state->io->in.address         = io->in.addresses[0];
 215         state->io->in.nb_flags        = io->in.nb_flags;
 216         state->io->in.broadcast       = false;
 217         state->io->in.ttl             = io->in.ttl;
 218         state->io->in.timeout         = 2;
 219         state->io->in.retries         = 2;
 220
 221         state->nbtsock     = nbtsock;
 222         state->address_idx = 0;
 223
 224         subreq = nbt_name_refresh_send(nbtsock, state->io);
 225         if (tevent_req_nomem(subreq, req)) {
 226                 return tevent_req_post(req, ev);
 227         }
 228
 229         subreq->async.fn = nbt_name_refresh_wins_handler;
 230         subreq->async.private_data = req;
 231
 232         return req;
 233 }
 234
 235 static void nbt_name_refresh_wins_handler(struct nbt_name_request *subreq)
 236 {
 237         struct tevent_req *req =
 238                 talloc_get_type_abort(subreq->async.private_data,
 239                 struct tevent_req);
 240         struct nbt_name_refresh_wins_state *state =
 241                 tevent_req_data(req,
 242                 struct nbt_name_refresh_wins_state);
 243         NTSTATUS status;
 244
 245         status = nbt_name_refresh_recv(subreq, state, state->io);
 246         if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT)) {
 247                 /* the refresh timed out - try the next WINS server */
 248                 state->wins_servers++;
 249                 if (state->wins_servers[0] == NULL) {
 250                         tevent_req_nterror(req, status);
 251                         return;
 252                 }
 253
 254                 state->address_idx = 0;
 255                 state->io->in.dest_addr = state->wins_servers[0];
 256                 state->io->in.dest_port = state->wins_port;
 257                 state->io->in.address   = state->addresses[0];
 258
 259                 subreq = nbt_name_refresh_send(state->nbtsock, state->io);
 260                 if (tevent_req_nomem(subreq, req)) {
 261                         return;
 262                 }
 263                 subreq->async.fn = nbt_name_refresh_wins_handler;
 264                 subreq->async.private_data = req;
 265         } else if (!NT_STATUS_IS_OK(status)) {
 266                 tevent_req_nterror(req, status);
 267                 return;
 268         }
 269
 270         if (state->io->out.rcode == 0 &&
 271             state->addresses[state->address_idx+1] != NULL) {
 272                 /* refresh our next address */
 273                 state->io->in.address = state->addresses[++(state->address_idx)];
 274                 subreq = nbt_name_refresh_send(state->nbtsock, state->io);
 275                 if (tevent_req_nomem(subreq, req)) {
 276                         return;
 277                 }
 278                 subreq->async.fn = nbt_name_refresh_wins_handler;
 279                 subreq->async.private_data = req;
 280                 return;
 281         }
 282
 283         tevent_req_done(req);
 284 }
 285
 286 /*
 287   multi-homed WINS name refresh - recv side
 288 */
 289 _PUBLIC_ NTSTATUS nbt_name_refresh_wins_recv(struct tevent_req *req,
 290                                              TALLOC_CTX *mem_ctx,
 291                                              struct nbt_name_refresh_wins *io)
 292 {
 293         struct nbt_name_refresh_wins_state *state =
 294                 tevent_req_data(req,
 295                 struct nbt_name_refresh_wins_state);
 296         NTSTATUS status;
 297
 298         if (tevent_req_is_nterror(req, &status)) {
 299                 tevent_req_received(req);
 300                 return status;
 301         }
 302
 303         io->out.wins_server = talloc_move(mem_ctx, &state->wins_servers[0]);
 304         io->out.rcode = state->io->out.rcode;
 305
 306         tevent_req_received(req);
 307         return NT_STATUS_OK;
 308 }
 309
 310 /*
 311   multi-homed WINS refresh - sync interface
 312 */
 313 _PUBLIC_ NTSTATUS nbt_name_refresh_wins(struct nbt_name_socket *nbtsock,
 314                                         TALLOC_CTX *mem_ctx,
 315                                         struct nbt_name_refresh_wins *io)
 316 {
 317         TALLOC_CTX *frame = talloc_stackframe();
 318         struct tevent_context *ev;
 319         struct tevent_req *subreq;
 320         NTSTATUS status;
 321
 322         /*
 323          * TODO: create a temporary event context
 324          */
 325         ev = nbtsock->event_ctx;
 326
 327         subreq = nbt_name_refresh_wins_send(frame, ev, nbtsock, io);
 328         if (subreq == NULL) {
 329                 talloc_free(frame);
 330                 return NT_STATUS_NO_MEMORY;
 331         }
 332
 333         if (!tevent_req_poll(subreq, ev)) {
 334                 status = map_nt_error_from_unix(errno);
 335                 talloc_free(frame);
 336                 return status;
 337         }
 338
 339         status = nbt_name_refresh_wins_recv(subreq, mem_ctx, io);
 340         if (!NT_STATUS_IS_OK(status)) {
 341                 talloc_free(frame);
 342                 return status;
 343         }
 344
 345         TALLOC_FREE(frame);
 346         return NT_STATUS_OK;
 347 }