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