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 {
  79         struct smb2_transport *transport;
  80
  81         transport = talloc_zero(parent_ctx, struct smb2_transport);
  82         if (!transport) return NULL;
  83
  84         transport->socket = talloc_steal(transport, sock);
  85
  86         /* setup the stream -> packet parser */
  87         transport->packet = packet_init(transport);
  88         if (transport->packet == NULL) {
  89                 talloc_free(transport);
  90                 return NULL;
  91         }
  92         packet_set_private(transport->packet, transport);
  93         packet_set_socket(transport->packet, transport->socket->sock);
  94         packet_set_callback(transport->packet, smb2_transport_finish_recv);
  95         packet_set_full_request(transport->packet, packet_full_request_nbt);
  96         packet_set_error_handler(transport->packet, smb2_transport_error);
  97         packet_set_event_context(transport->packet, transport->socket->event.ctx);
  98         packet_set_nofree(transport->packet);
  99
 100         /* take over event handling from the socket layer - it only
 101            handles events up until we are connected */
 102         talloc_free(transport->socket->event.fde);
 103         transport->socket->event.fde = event_add_fd(transport->socket->event.ctx,
 104                                                     transport->socket,
 105                                                     socket_get_fd(transport->socket->sock),
 106                                                     EVENT_FD_READ,
 107                                                     smb2_transport_event_handler,
 108                                                     transport);
 109
 110         packet_set_fde(transport->packet, transport->socket->event.fde);
 111         packet_set_serialise(transport->packet);
 112
 113         talloc_set_destructor(transport, transport_destructor);
 114
 115         transport->options.timeout = 30;
 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 bool smb2_handle_oplock_break(struct smb2_transport *transport,
 144                                      const DATA_BLOB *blob)
 145 {
 146         uint8_t *hdr;
 147         uint16_t opcode;
 148         uint64_t seqnum;
 149
 150         hdr = blob->data+NBT_HDR_SIZE;
 151
 152         if (blob->length < (SMB2_MIN_SIZE+0x18)) {
 153                 DEBUG(1,("Discarding smb2 oplock reply of size %u\n",
 154                          blob->length));
 155                 return false;
 156         }
 157
 158         opcode  = SVAL(hdr, SMB2_HDR_OPCODE);
 159         seqnum  = BVAL(hdr, SMB2_HDR_MESSAGE_ID);
 160
 161         if ((opcode != SMB2_OP_BREAK) ||
 162             (seqnum != UINT64_MAX)) {
 163                 return false;
 164         }
 165
 166         if (transport->oplock.handler) {
 167                 uint8_t *body = hdr+SMB2_HDR_BODY;
 168                 struct smb2_handle h;
 169                 uint8_t level;
 170
 171                 level = CVAL(body, 0x02);
 172                 smb2_pull_handle(body+0x08, &h);
 173
 174                 transport->oplock.handler(transport, &h, level,
 175                                           transport->oplock.private_data);
 176         }
 177
 178         return true;
 179 }
 180
 181 /*
 182   we have a full request in our receive buffer - match it to a pending request
 183   and process
 184  */
 185 static NTSTATUS smb2_transport_finish_recv(void *private, DATA_BLOB blob)
 186 {
 187         struct smb2_transport *transport = talloc_get_type(private,
 188                                                              struct smb2_transport);
 189         uint8_t *buffer, *hdr;
 190         int len;
 191         struct smb2_request *req = NULL;
 192         uint64_t seqnum;
 193         uint32_t flags;
 194         uint16_t buffer_code;
 195         uint32_t dynamic_size;
 196         uint32_t i;
 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         if (smb2_handle_oplock_break(transport, &blob)) {
 209                 talloc_free(buffer);
 210                 return NT_STATUS_OK;
 211         }
 212
 213         flags   = IVAL(hdr, SMB2_HDR_FLAGS);
 214         seqnum  = BVAL(hdr, SMB2_HDR_MESSAGE_ID);
 215
 216         /* match the incoming request against the list of pending requests */
 217         for (req=transport->pending_recv; req; req=req->next) {
 218                 if (req->seqnum == seqnum) break;
 219         }
 220
 221         if (!req) {
 222                 DEBUG(1,("Discarding unmatched reply with seqnum 0x%llx op %d\n",
 223                          (long long)seqnum, SVAL(hdr, SMB2_HDR_OPCODE)));
 224                 goto error;
 225         }
 226
 227         /* fill in the 'in' portion of the matching request */
 228         req->in.buffer = buffer;
 229         talloc_steal(req, buffer);
 230         req->in.size = len;
 231         req->in.allocated = req->in.size;
 232
 233         req->in.hdr       = hdr;
 234         req->in.body      = hdr+SMB2_HDR_BODY;
 235         req->in.body_size = req->in.size - (SMB2_HDR_BODY+NBT_HDR_SIZE);
 236         req->status       = NT_STATUS(IVAL(hdr, SMB2_HDR_STATUS));
 237
 238         if (NT_STATUS_EQUAL(req->status, STATUS_PENDING)) {
 239                 if (flags & 0x00000002) {
 240                         req->cancel.can_cancel = true;
 241                         req->cancel.pending_id = IVAL(hdr, SMB2_HDR_PID);
 242                         for (i=0; i< req->cancel.do_cancel; i++) {
 243                                 smb2_cancel(req);
 244                         }
 245                 }
 246                 talloc_free(buffer);
 247                 return NT_STATUS_OK;
 248         }
 249
 250         buffer_code = SVAL(req->in.body, 0);
 251         req->in.body_fixed = (buffer_code & ~1);
 252         req->in.dynamic = NULL;
 253         dynamic_size = req->in.body_size - req->in.body_fixed;
 254         if (dynamic_size != 0 && (buffer_code & 1)) {
 255                 req->in.dynamic = req->in.body + req->in.body_fixed;
 256                 if (smb2_oob(&req->in, req->in.dynamic, dynamic_size)) {
 257                         DEBUG(1,("SMB2 request invalid dynamic size 0x%x\n",
 258                                  dynamic_size));
 259                         goto error;
 260                 }
 261         }
 262
 263         smb2_setup_bufinfo(req);
 264
 265         DEBUG(2, ("SMB2 RECV seqnum=0x%llx\n", (long long)req->seqnum));
 266         dump_data(5, req->in.body, req->in.body_size);
 267
 268         /* if this request has an async handler then call that to
 269            notify that the reply has been received. This might destroy
 270            the request so it must happen last */
 271         DLIST_REMOVE(transport->pending_recv, req);
 272         req->state = SMB2_REQUEST_DONE;
 273         if (req->async.fn) {
 274                 req->async.fn(req);
 275         }
 276         return NT_STATUS_OK;
 277
 278 error:
 279         dump_data(5, buffer, len);
 280         if (req) {
 281                 DLIST_REMOVE(transport->pending_recv, req);
 282                 req->state = SMB2_REQUEST_ERROR;
 283                 if (req->async.fn) {
 284                         req->async.fn(req);
 285                 }
 286         } else {
 287                 talloc_free(buffer);
 288         }
 289         return NT_STATUS_UNSUCCESSFUL;
 290 }
 291
 292 /*
 293   handle timeouts of individual smb requests
 294 */
 295 static void smb2_timeout_handler(struct event_context *ev, struct timed_event *te,
 296                                  struct timeval t, void *private)
 297 {
 298         struct smb2_request *req = talloc_get_type(private, struct smb2_request);
 299
 300         if (req->state == SMB2_REQUEST_RECV) {
 301                 DLIST_REMOVE(req->transport->pending_recv, req);
 302         }
 303         req->status = NT_STATUS_IO_TIMEOUT;
 304         req->state = SMB2_REQUEST_ERROR;
 305         if (req->async.fn) {
 306                 req->async.fn(req);
 307         }
 308 }
 309
 310
 311 /*
 312   destroy a request
 313 */
 314 static int smb2_request_destructor(struct smb2_request *req)
 315 {
 316         if (req->state == SMB2_REQUEST_RECV) {
 317                 DLIST_REMOVE(req->transport->pending_recv, req);
 318         }
 319         return 0;
 320 }
 321
 322
 323 /*
 324   put a request into the send queue
 325 */
 326 void smb2_transport_send(struct smb2_request *req)
 327 {
 328         DATA_BLOB blob;
 329         NTSTATUS status;
 330
 331         _smb2_setlen(req->out.buffer, req->out.size - NBT_HDR_SIZE);
 332
 333         DEBUG(2, ("SMB2 send seqnum=0x%llx\n", (long long)req->seqnum));
 334         dump_data(5, req->out.body, req->out.body_size);
 335
 336         /* check if the transport is dead */
 337         if (req->transport->socket->sock == NULL) {
 338                 req->state = SMB2_REQUEST_ERROR;
 339                 req->status = NT_STATUS_NET_WRITE_FAULT;
 340                 return;
 341         }
 342
 343         blob = data_blob_const(req->out.buffer, req->out.size);
 344         status = packet_send(req->transport->packet, blob);
 345         if (!NT_STATUS_IS_OK(status)) {
 346                 req->state = SMB2_REQUEST_ERROR;
 347                 req->status = status;
 348                 return;
 349         }
 350
 351         req->state = SMB2_REQUEST_RECV;
 352         DLIST_ADD(req->transport->pending_recv, req);
 353
 354         /* add a timeout */
 355         if (req->transport->options.timeout) {
 356                 event_add_timed(req->transport->socket->event.ctx, req,
 357                                 timeval_current_ofs(req->transport->options.timeout, 0),
 358                                 smb2_timeout_handler, req);
 359         }
 360
 361         talloc_set_destructor(req, smb2_request_destructor);
 362 }
 363
 364 static void idle_handler(struct event_context *ev,
 365                          struct timed_event *te, struct timeval t, void *private)
 366 {
 367         struct smb2_transport *transport = talloc_get_type(private,
 368                                                            struct smb2_transport);
 369         struct timeval next = timeval_add(&t, 0, transport->idle.period);
 370         transport->socket->event.te = event_add_timed(transport->socket->event.ctx,
 371                                                       transport,
 372                                                       next,
 373                                                       idle_handler, transport);
 374         transport->idle.func(transport, transport->idle.private);
 375 }
 376
 377 /*
 378   setup the idle handler for a transport
 379   the period is in microseconds
 380 */
 381 void smb2_transport_idle_handler(struct smb2_transport *transport,
 382                                  void (*idle_func)(struct smb2_transport *, void *),
 383                                  uint64_t period,
 384                                  void *private)
 385 {
 386         transport->idle.func = idle_func;
 387         transport->idle.private = private;
 388         transport->idle.period = period;
 389
 390         if (transport->socket->event.te != NULL) {
 391                 talloc_free(transport->socket->event.te);
 392         }
 393
 394         transport->socket->event.te = event_add_timed(transport->socket->event.ctx,
 395                                                       transport,
 396                                                       timeval_current_ofs(0, period),
 397                                                       idle_handler, transport);
 398 }