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