source4/libcli/smb2/transport.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    SMB2 client transport context management functions
   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/raw/libcliraw.h"
  24 #include "libcli/raw/raw_proto.h"
  25 #include "libcli/smb2/smb2.h"
  26 #include "libcli/smb2/smb2_calls.h"
  27 #include "lib/socket/socket.h"
  28 #include "lib/events/events.h"
  29 #include "lib/stream/packet.h"
  30 #include "lib/util/dlinklist.h"
  31
  32
  33 /*
  34   an event has happened on the socket
  35 */
  36 static void smb2_transport_event_handler(struct event_context *ev,
  37                                          struct fd_event *fde,
  38                                          uint16_t flags, void *private)
  39 {
  40         struct smb2_transport *transport = talloc_get_type(private,
  41                                                            struct smb2_transport);
  42         if (flags & EVENT_FD_READ) {
  43                 packet_recv(transport->packet);
  44                 return;
  45         }
  46         if (flags & EVENT_FD_WRITE) {
  47                 packet_queue_run(transport->packet);
  48         }
  49 }
  50
  51 /*
  52   destroy a transport
  53  */
  54 static int transport_destructor(struct smb2_transport *transport)
  55 {
  56         smb2_transport_dead(transport, NT_STATUS_LOCAL_DISCONNECT);
  57         return 0;
  58 }
  59
  60
  61 /*
  62   handle receive errors
  63 */
  64 static void smb2_transport_error(void *private, NTSTATUS status)
  65 {
  66         struct smb2_transport *transport = talloc_get_type(private,
  67                                                            struct smb2_transport);
  68         smb2_transport_dead(transport, status);
  69 }
  70
  71 static NTSTATUS smb2_transport_finish_recv(void *private, DATA_BLOB blob);
  72
  73 /*
  74   create a transport structure based on an established socket
  75 */
  76 struct smb2_transport *smb2_transport_init(struct smbcli_socket *sock,
  77                                            TALLOC_CTX *parent_ctx,
  78                                            struct smbcli_options *options)
  79 {
  80         struct smb2_transport *transport;
  81
  82         transport = talloc_zero(parent_ctx, struct smb2_transport);
  83         if (!transport) return NULL;
  84
  85         transport->socket = talloc_steal(transport, sock);
  86         transport->options = *options;
  87
  88         /* setup the stream -> packet parser */
  89         transport->packet = packet_init(transport);
  90         if (transport->packet == NULL) {
  91                 talloc_free(transport);
  92                 return NULL;
  93         }
  94         packet_set_private(transport->packet, transport);
  95         packet_set_socket(transport->packet, transport->socket->sock);
  96         packet_set_callback(transport->packet, smb2_transport_finish_recv);
  97         packet_set_full_request(transport->packet, packet_full_request_nbt);
  98         packet_set_error_handler(transport->packet, smb2_transport_error);
  99         packet_set_event_context(transport->packet, transport->socket->event.ctx);
 100         packet_set_nofree(transport->packet);
 101
 102         /* take over event handling from the socket layer - it only
 103            handles events up until we are connected */
 104         talloc_free(transport->socket->event.fde);
 105         transport->socket->event.fde = event_add_fd(transport->socket->event.ctx,
 106                                                     transport->socket,
 107                                                     socket_get_fd(transport->socket->sock),
 108                                                     EVENT_FD_READ,
 109                                                     smb2_transport_event_handler,
 110                                                     transport);
 111
 112         packet_set_fde(transport->packet, transport->socket->event.fde);
 113         packet_set_serialise(transport->packet);
 114
 115         talloc_set_destructor(transport, transport_destructor);
 116
 117         return transport;
 118 }
 119
 120 /*
 121   mark the transport as dead
 122 */
 123 void smb2_transport_dead(struct smb2_transport *transport, NTSTATUS status)
 124 {
 125         smbcli_sock_dead(transport->socket);
 126
 127         if (NT_STATUS_EQUAL(NT_STATUS_UNSUCCESSFUL, status)) {
 128                 status = NT_STATUS_UNEXPECTED_NETWORK_ERROR;
 129         }
 130
 131         /* kill all pending receives */
 132         while (transport->pending_recv) {
 133                 struct smb2_request *req = transport->pending_recv;
 134                 req->state = SMB2_REQUEST_ERROR;
 135                 req->status = status;
 136                 DLIST_REMOVE(transport->pending_recv, req);
 137                 if (req->async.fn) {
 138                         req->async.fn(req);
 139                 }
 140         }
 141 }
 142
 143 static NTSTATUS smb2_handle_oplock_break(struct smb2_transport *transport,
 144                                          const DATA_BLOB *blob)
 145 {
 146         uint8_t *hdr;
 147         uint16_t opcode;
 148
 149         hdr = blob->data+NBT_HDR_SIZE;
 150
 151         if (blob->length < (SMB2_MIN_SIZE+0x18)) {
 152                 DEBUG(1,("Discarding smb2 oplock reply of size %u\n",
 153                          (unsigned)blob->length));
 154                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
 155         }
 156
 157         opcode  = SVAL(hdr, SMB2_HDR_OPCODE);
 158
 159         if (opcode != SMB2_OP_BREAK) {
 160                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
 161         }
 162
 163         if (transport->oplock.handler) {
 164                 uint8_t *body = hdr+SMB2_HDR_BODY;
 165                 struct smb2_handle h;
 166                 uint8_t level;
 167
 168                 level = CVAL(body, 0x02);
 169                 smb2_pull_handle(body+0x08, &h);
 170
 171                 transport->oplock.handler(transport, &h, level,
 172                                           transport->oplock.private_data);
 173         } else {
 174                 DEBUG(5,("Got SMB2 oplock break with no handler\n"));
 175         }
 176
 177         return NT_STATUS_OK;
 178 }
 179
 180 /*
 181   we have a full request in our receive buffer - match it to a pending request
 182   and process
 183  */
 184 static NTSTATUS smb2_transport_finish_recv(void *private, DATA_BLOB blob)
 185 {
 186         struct smb2_transport *transport = talloc_get_type(private,
 187                                                              struct smb2_transport);
 188         uint8_t *buffer, *hdr;
 189         int len;
 190         struct smb2_request *req = NULL;
 191         uint64_t seqnum;
 192         uint32_t flags;
 193         uint16_t buffer_code;
 194         uint32_t dynamic_size;
 195         uint32_t i;
 196         NTSTATUS status;
 197
 198         buffer = blob.data;
 199         len = blob.length;
 200
 201         hdr = buffer+NBT_HDR_SIZE;
 202
 203         if (len < SMB2_MIN_SIZE) {
 204                 DEBUG(1,("Discarding smb2 reply of size %d\n", len));
 205                 goto error;
 206         }
 207
 208         status = smb2_check_signature(transport, buffer, len);
 209         if (!NT_STATUS_IS_OK(status)) {
 210                 talloc_free(buffer);
 211                 return status;
 212         }
 213
 214         flags   = IVAL(hdr, SMB2_HDR_FLAGS);
 215         seqnum  = BVAL(hdr, SMB2_HDR_MESSAGE_ID);
 216
 217         /* see MS-SMB2 3.2.5.19 */
 218         if (seqnum == UINT64_MAX) {
 219                 return smb2_handle_oplock_break(transport, &blob);
 220         }
 221
 222         /* match the incoming request against the list of pending requests */
 223         for (req=transport->pending_recv; req; req=req->next) {
 224                 if (req->seqnum == seqnum) break;
 225         }
 226
 227         if (!req) {
 228                 DEBUG(1,("Discarding unmatched reply with seqnum 0x%llx op %d\n",
 229                          (long long)seqnum, SVAL(hdr, SMB2_HDR_OPCODE)));
 230                 goto error;
 231         }
 232
 233         /* fill in the 'in' portion of the matching request */
 234         req->in.buffer = buffer;
 235         talloc_steal(req, buffer);
 236         req->in.size = len;
 237         req->in.allocated = req->in.size;
 238
 239         req->in.hdr       = hdr;
 240         req->in.body      = hdr+SMB2_HDR_BODY;
 241         req->in.body_size = req->in.size - (SMB2_HDR_BODY+NBT_HDR_SIZE);
 242         req->status       = NT_STATUS(IVAL(hdr, SMB2_HDR_STATUS));
 243
 244         if (NT_STATUS_EQUAL(req->status, STATUS_PENDING)) {
 245                 if (flags & 0x00000002) {
 246                         req->cancel.can_cancel = true;
 247                         req->cancel.pending_id = IVAL(hdr, SMB2_HDR_PID);
 248                         for (i=0; i< req->cancel.do_cancel; i++) {
 249                                 smb2_cancel(req);
 250                         }
 251                 }
 252                 talloc_free(buffer);
 253                 return NT_STATUS_OK;
 254         }
 255
 256         buffer_code = SVAL(req->in.body, 0);
 257         req->in.body_fixed = (buffer_code & ~1);
 258         req->in.dynamic = NULL;
 259         dynamic_size = req->in.body_size - req->in.body_fixed;
 260         if (dynamic_size != 0 && (buffer_code & 1)) {
 261                 req->in.dynamic = req->in.body + req->in.body_fixed;
 262                 if (smb2_oob(&req->in, req->in.dynamic, dynamic_size)) {
 263                         DEBUG(1,("SMB2 request invalid dynamic size 0x%x\n",
 264                                  dynamic_size));
 265                         goto error;
 266                 }
 267         }
 268
 269         smb2_setup_bufinfo(req);
 270
 271         DEBUG(2, ("SMB2 RECV seqnum=0x%llx\n", (long long)req->seqnum));
 272         dump_data(5, req->in.body, req->in.body_size);
 273
 274         /* if this request has an async handler then call that to
 275            notify that the reply has been received. This might destroy
 276            the request so it must happen last */
 277         DLIST_REMOVE(transport->pending_recv, req);
 278         req->state = SMB2_REQUEST_DONE;
 279         if (req->async.fn) {
 280                 req->async.fn(req);
 281         }
 282         return NT_STATUS_OK;
 283
 284 error:
 285         dump_data(5, buffer, len);
 286         if (req) {
 287                 DLIST_REMOVE(transport->pending_recv, req);
 288                 req->state = SMB2_REQUEST_ERROR;
 289                 if (req->async.fn) {
 290                         req->async.fn(req);
 291                 }
 292         } else {
 293                 talloc_free(buffer);
 294         }
 295         return NT_STATUS_UNSUCCESSFUL;
 296 }
 297
 298 /*
 299   handle timeouts of individual smb requests
 300 */
 301 static void smb2_timeout_handler(struct event_context *ev, struct timed_event *te,
 302                                  struct timeval t, void *private)
 303 {
 304         struct smb2_request *req = talloc_get_type(private, struct smb2_request);
 305
 306         if (req->state == SMB2_REQUEST_RECV) {
 307                 DLIST_REMOVE(req->transport->pending_recv, req);
 308         }
 309         req->status = NT_STATUS_IO_TIMEOUT;
 310         req->state = SMB2_REQUEST_ERROR;
 311         if (req->async.fn) {
 312                 req->async.fn(req);
 313         }
 314 }
 315
 316
 317 /*
 318   destroy a request
 319 */
 320 static int smb2_request_destructor(struct smb2_request *req)
 321 {
 322         if (req->state == SMB2_REQUEST_RECV) {
 323                 DLIST_REMOVE(req->transport->pending_recv, req);
 324         }
 325         return 0;
 326 }
 327
 328
 329 /*
 330   put a request into the send queue
 331 */
 332 void smb2_transport_send(struct smb2_request *req)
 333 {
 334         DATA_BLOB blob;
 335         NTSTATUS status;
 336
 337         _smb2_setlen(req->out.buffer, req->out.size - NBT_HDR_SIZE);
 338
 339         DEBUG(2, ("SMB2 send seqnum=0x%llx\n", (long long)req->seqnum));
 340         dump_data(5, req->out.body, req->out.body_size);
 341
 342         /* check if the transport is dead */
 343         if (req->transport->socket->sock == NULL) {
 344                 req->state = SMB2_REQUEST_ERROR;
 345                 req->status = NT_STATUS_NET_WRITE_FAULT;
 346                 return;
 347         }
 348
 349         status = smb2_sign_message(req);
 350         if (!NT_STATUS_IS_OK(status)) {
 351                 req->state = SMB2_REQUEST_ERROR;
 352                 req->status = status;
 353                 return;
 354         }
 355
 356         blob = data_blob_const(req->out.buffer, req->out.size);
 357         status = packet_send(req->transport->packet, blob);
 358         if (!NT_STATUS_IS_OK(status)) {
 359                 req->state = SMB2_REQUEST_ERROR;
 360                 req->status = status;
 361                 return;
 362         }
 363
 364         req->state = SMB2_REQUEST_RECV;
 365         DLIST_ADD(req->transport->pending_recv, req);
 366
 367         /* add a timeout */
 368         if (req->transport->options.request_timeout) {
 369                 event_add_timed(req->transport->socket->event.ctx, req,
 370                                 timeval_current_ofs(req->transport->options.request_timeout, 0),
 371                                 smb2_timeout_handler, req);
 372         }
 373
 374         talloc_set_destructor(req, smb2_request_destructor);
 375 }
 376
 377 static void idle_handler(struct event_context *ev,
 378                          struct timed_event *te, struct timeval t, void *private)
 379 {
 380         struct smb2_transport *transport = talloc_get_type(private,
 381                                                            struct smb2_transport);
 382         struct timeval next = timeval_add(&t, 0, transport->idle.period);
 383         transport->socket->event.te = event_add_timed(transport->socket->event.ctx,
 384                                                       transport,
 385                                                       next,
 386                                                       idle_handler, transport);
 387         transport->idle.func(transport, transport->idle.private);
 388 }
 389
 390 /*
 391   setup the idle handler for a transport
 392   the period is in microseconds
 393 */
 394 void smb2_transport_idle_handler(struct smb2_transport *transport,
 395                                  void (*idle_func)(struct smb2_transport *, void *),
 396                                  uint64_t period,
 397                                  void *private)
 398 {
 399         transport->idle.func = idle_func;
 400         transport->idle.private = private;
 401         transport->idle.period = period;
 402
 403         if (transport->socket->event.te != NULL) {
 404                 talloc_free(transport->socket->event.te);
 405         }
 406
 407         transport->socket->event.te = event_add_timed(transport->socket->event.ctx,
 408                                                       transport,
 409                                                       timeval_current_ofs(0, period),
 410                                                       idle_handler, transport);
 411 }