source4/nbt_server/dgram/request.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    NBT datagram server
   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 "nbt_server/nbt_server.h"
  24 #include "samba/service_task.h"
  25 #include "lib/socket/socket.h"
  26 #include "libcli/resolve/resolve.h"
  27 #include "nbt_server/dgram/proto.h"
  28 #include "librpc/gen_ndr/ndr_nbt.h"
  29 #include "param/param.h"
  30 #include "lib/util/util_str_escape.h"
  31 #include "lib/util/util_net.h"
  32 #include "../source3/include/fstring.h"
  33 #include "../source3/libsmb/nmblib.h"
  34 #include "../source3/libsmb/unexpected.h"
  35
  36 /*
  37   a list of mailslots that we have static handlers for
  38 */
  39 static const struct {
  40         const char *mailslot_name;
  41         dgram_mailslot_handler_t handler;
  42 } mailslot_handlers[] = {
  43         /* Handle both NTLOGON and NETLOGON in the same function, as
  44          * they are very similar */
  45         { NBT_MAILSLOT_NETLOGON, nbtd_mailslot_netlogon_handler },
  46         { NBT_MAILSLOT_NTLOGON,  nbtd_mailslot_netlogon_handler },
  47         { NBT_MAILSLOT_BROWSE,   nbtd_mailslot_browse_handler }
  48 };
  49
  50 /*
  51   receive an incoming dgram request. This is used for general datagram
  52   requests. Mailslot requests for our listening mailslots
  53   are handled in the specific mailslot handlers
  54 */
  55 void dgram_request_handler(struct nbt_dgram_socket *dgmsock,
  56                            struct nbt_dgram_packet *packet,
  57                            struct socket_address *src)
  58 {
  59         struct nbtd_interface *iface =
  60                 talloc_get_type_abort(dgmsock->incoming.private_data,
  61                 struct nbtd_interface);
  62         struct nbtd_server *nbtsrv = iface->nbtsrv;
  63         const char *mailslot_name = NULL;
  64         struct packet_struct *pstruct = NULL;
  65         DATA_BLOB blob = { .length = 0, };
  66         enum ndr_err_code ndr_err;
  67
  68         mailslot_name = dgram_mailslot_name(packet);
  69         if (mailslot_name != NULL) {
  70                 DBG_DEBUG("Unexpected mailslot[%s] datagram request from %s:%d\n",
  71                           log_escape(packet, mailslot_name),
  72                           src->addr, src->port);
  73         } else {
  74                 DBG_DEBUG("Unexpected general datagram request from %s:%d\n",
  75                           src->addr, src->port);
  76         }
  77
  78         if (CHECK_DEBUGLVL(DBGLVL_DEBUG)) {
  79                 NDR_PRINT_DEBUG(nbt_dgram_packet, packet);
  80         }
  81
  82         /*
  83          * For now we only pass DGRAM_DIRECT_UNIQUE
  84          * messages via nb_packet_dispatch() to
  85          * nbtsrv->unexpected_server
  86          */
  87         if (packet->msg_type != DGRAM_DIRECT_UNIQUE) {
  88                 return;
  89         }
  90
  91         ndr_err = ndr_push_struct_blob(&blob, packet, packet,
  92                         (ndr_push_flags_fn_t)ndr_push_nbt_dgram_packet);
  93         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
  94                 DBG_ERR("ndr_push_nbt_dgram_packet - %s\n",
  95                         ndr_errstr(ndr_err));
  96                 return;
  97         }
  98
  99         pstruct = parse_packet((char *)blob.data,
 100                                blob.length,
 101                                DGRAM_PACKET,
 102                                interpret_addr2(src->addr),
 103                                src->port);
 104         if (pstruct != NULL) {
 105                 nb_packet_dispatch(nbtsrv->unexpected_server, pstruct);
 106                 free_packet(pstruct);
 107         }
 108 }
 109
 110
 111 /*
 112   setup the port 138 datagram listener for a given interface
 113 */
 114 NTSTATUS nbtd_dgram_setup(struct nbtd_interface *iface, const char *bind_address)
 115 {
 116         struct nbt_dgram_socket *bcast_dgmsock = NULL;
 117         struct nbtd_server *nbtsrv = iface->nbtsrv;
 118         struct socket_address *bcast_addr, *bind_addr;
 119         NTSTATUS status;
 120         TALLOC_CTX *tmp_ctx = talloc_new(iface);
 121         /* the list of mailslots that we are interested in */
 122         size_t i;
 123
 124         if (!tmp_ctx) {
 125                 return NT_STATUS_NO_MEMORY;
 126         }
 127
 128         if (strcmp("0.0.0.0", iface->netmask) != 0) {
 129                 /* listen for broadcasts on port 138 */
 130                 bcast_dgmsock = nbt_dgram_socket_init(iface, nbtsrv->task->event_ctx);
 131                 if (!bcast_dgmsock) {
 132                         talloc_free(tmp_ctx);
 133                         return NT_STATUS_NO_MEMORY;
 134                 }
 135
 136                 bcast_addr = socket_address_from_strings(tmp_ctx, bcast_dgmsock->sock->backend_name,
 137                                                          iface->bcast_address,
 138                                                          lpcfg_dgram_port(iface->nbtsrv->task->lp_ctx));
 139                 if (!bcast_addr) {
 140                         talloc_free(tmp_ctx);
 141                         return NT_STATUS_NO_MEMORY;
 142                 }
 143
 144                 status = socket_listen(bcast_dgmsock->sock, bcast_addr, 0, 0);
 145                 if (!NT_STATUS_IS_OK(status)) {
 146                         talloc_free(tmp_ctx);
 147                         DEBUG(0,("Failed to bind to %s:%d - %s\n",
 148                                  iface->bcast_address, lpcfg_dgram_port(iface->nbtsrv->task->lp_ctx),
 149                                  nt_errstr(status)));
 150                         return status;
 151                 }
 152
 153                 dgram_set_incoming_handler(bcast_dgmsock, dgram_request_handler, iface);
 154         }
 155
 156         /* listen for unicasts on port 138 */
 157         iface->dgmsock = nbt_dgram_socket_init(iface, nbtsrv->task->event_ctx);
 158         if (!iface->dgmsock) {
 159                 talloc_free(tmp_ctx);
 160                 return NT_STATUS_NO_MEMORY;
 161         }
 162
 163         bind_addr = socket_address_from_strings(tmp_ctx, iface->dgmsock->sock->backend_name,
 164                                                 bind_address, lpcfg_dgram_port(iface->nbtsrv->task->lp_ctx));
 165         if (!bind_addr) {
 166                 talloc_free(tmp_ctx);
 167                 return NT_STATUS_NO_MEMORY;
 168         }
 169
 170         status = socket_listen(iface->dgmsock->sock, bind_addr, 0, 0);
 171         if (!NT_STATUS_IS_OK(status)) {
 172                 talloc_free(tmp_ctx);
 173                 DEBUG(0,("Failed to bind to %s:%d - %s\n",
 174                          bind_address, lpcfg_dgram_port(iface->nbtsrv->task->lp_ctx), nt_errstr(status)));
 175                 return status;
 176         }
 177
 178         dgram_set_incoming_handler(iface->dgmsock, dgram_request_handler, iface);
 179
 180         talloc_free(tmp_ctx);
 181
 182         for (i=0;i<ARRAY_SIZE(mailslot_handlers);i++) {
 183                 /* note that we don't need to keep the pointer
 184                    to the dgmslot around - the callback is all
 185                    we need */
 186                 struct dgram_mailslot_handler *dgmslot;
 187
 188                 if (bcast_dgmsock) {
 189                         dgmslot = dgram_mailslot_listen(bcast_dgmsock,
 190                                                 mailslot_handlers[i].mailslot_name,
 191                                                 mailslot_handlers[i].handler, iface);
 192                         NT_STATUS_HAVE_NO_MEMORY(dgmslot);
 193                 }
 194
 195                 dgmslot = dgram_mailslot_listen(iface->dgmsock,
 196                                                 mailslot_handlers[i].mailslot_name,
 197                                                 mailslot_handlers[i].handler, iface);
 198                 NT_STATUS_HAVE_NO_MEMORY(dgmslot);
 199         }
 200
 201         return NT_STATUS_OK;
 202 }