source/libcli/raw/clitransport.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    SMB client transport context management functions
   4
   5    Copyright (C) Andrew Tridgell 1994-2005
   6    Copyright (C) James Myers 2003 <myersjj@samba.org>
   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/raw/libcliraw.h"
  25 #include "system/time.h"
  26 #include "dlinklist.h"
  27 #include "events.h"
  28
  29
  30 static void smbcli_transport_process_recv(struct smbcli_transport *transport);
  31 static void smbcli_transport_process_send(struct smbcli_transport *transport);
  32
  33 /*
  34   an event has happened on the socket
  35 */
  36 static void smbcli_transport_event_handler(struct event_context *ev,
  37                                            struct fd_event *fde,
  38                                            uint16_t flags, void *private)
  39 {
  40         struct smbcli_transport *transport = talloc_get_type(private,
  41                                                              struct smbcli_transport);
  42         if (flags & EVENT_FD_READ) {
  43                 smbcli_transport_process_recv(transport);
  44                 return;
  45         }
  46         if (flags & EVENT_FD_WRITE) {
  47                 smbcli_transport_process_send(transport);
  48         }
  49 }
  50
  51 /*
  52   destroy a transport
  53  */
  54 static int transport_destructor(void *ptr)
  55 {
  56         struct smbcli_transport *transport = ptr;
  57
  58         smbcli_transport_dead(transport);
  59         return 0;
  60 }
  61
  62 /*
  63   create a transport structure based on an established socket
  64 */
  65 struct smbcli_transport *smbcli_transport_init(struct smbcli_socket *sock,
  66                                                TALLOC_CTX *parent_ctx, BOOL primary)
  67 {
  68         struct smbcli_transport *transport;
  69
  70         transport = talloc_zero(parent_ctx, struct smbcli_transport);
  71         if (!transport) return NULL;
  72
  73         if (primary) {
  74                 transport->socket = talloc_steal(transport, sock);
  75         } else {
  76                 transport->socket = talloc_reference(transport, sock);
  77         }
  78         transport->negotiate.protocol = PROTOCOL_NT1;
  79         transport->options.use_spnego = lp_use_spnego();
  80         transport->options.max_xmit = lp_max_xmit();
  81         transport->options.max_mux = lp_maxmux();
  82
  83         transport->negotiate.max_xmit = transport->options.max_xmit;
  84
  85         smbcli_init_signing(transport);
  86
  87         ZERO_STRUCT(transport->called);
  88
  89         /* take over event handling from the socket layer - it only
  90            handles events up until we are connected */
  91         talloc_free(transport->socket->event.fde);
  92         transport->socket->event.fde = event_add_fd(transport->socket->event.ctx,
  93                                                     transport->socket,
  94                                                     socket_get_fd(transport->socket->sock),
  95                                                     EVENT_FD_READ,
  96                                                     smbcli_transport_event_handler,
  97                                                     transport);
  98
  99         talloc_set_destructor(transport, transport_destructor);
 100
 101         return transport;
 102 }
 103
 104 /*
 105   mark the transport as dead
 106 */
 107 void smbcli_transport_dead(struct smbcli_transport *transport)
 108 {
 109         smbcli_sock_dead(transport->socket);
 110
 111         /* all pending sends become errors */
 112         while (transport->pending_send) {
 113                 struct smbcli_request *req = transport->pending_send;
 114                 req->state = SMBCLI_REQUEST_ERROR;
 115                 req->status = NT_STATUS_NET_WRITE_FAULT;
 116                 DLIST_REMOVE(transport->pending_send, req);
 117                 if (req->async.fn) {
 118                         req->async.fn(req);
 119                 }
 120         }
 121
 122         /* as do all pending receives */
 123         while (transport->pending_recv) {
 124                 struct smbcli_request *req = transport->pending_recv;
 125                 req->state = SMBCLI_REQUEST_ERROR;
 126                 req->status = NT_STATUS_NET_WRITE_FAULT;
 127                 DLIST_REMOVE(transport->pending_recv, req);
 128                 if (req->async.fn) {
 129                         req->async.fn(req);
 130                 }
 131         }
 132 }
 133
 134
 135 /*
 136   enable select for write on a transport
 137 */
 138 static void smbcli_transport_write_enable(struct smbcli_transport *transport)
 139 {
 140         struct fd_event *fde = transport->socket->event.fde;
 141         EVENT_FD_WRITEABLE(fde);
 142 }
 143
 144 /*
 145   disable select for write on a transport
 146 */
 147 static void smbcli_transport_write_disable(struct smbcli_transport *transport)
 148 {
 149         struct fd_event *fde = transport->socket->event.fde;
 150         EVENT_FD_NOT_WRITEABLE(fde);
 151 }
 152
 153 /*
 154   send a session request
 155 */
 156 struct smbcli_request *smbcli_transport_connect_send(struct smbcli_transport *transport,
 157                                                      struct nbt_name *calling,
 158                                                      struct nbt_name *called)
 159 {
 160         uint8_t *p;
 161         struct smbcli_request *req;
 162         DATA_BLOB calling_blob, called_blob;
 163         TALLOC_CTX *tmp_ctx = talloc_new(transport);
 164         NTSTATUS status;
 165
 166         status = nbt_name_dup(transport, called, &transport->called);
 167         if (!NT_STATUS_IS_OK(status)) goto failed;
 168
 169         status = nbt_name_to_blob(tmp_ctx, &calling_blob, calling);
 170         if (!NT_STATUS_IS_OK(status)) goto failed;
 171
 172         status = nbt_name_to_blob(tmp_ctx, &called_blob, called);
 173         if (!NT_STATUS_IS_OK(status)) goto failed;
 174
 175         /* allocate output buffer */
 176         req = smbcli_request_setup_nonsmb(transport,
 177                                           NBT_HDR_SIZE +
 178                                           calling_blob.length + called_blob.length);
 179         if (req == NULL) goto failed;
 180
 181         /* put in the destination name */
 182         p = req->out.buffer + NBT_HDR_SIZE;
 183         memcpy(p, called_blob.data, called_blob.length);
 184         p += called_blob.length;
 185
 186         memcpy(p, calling_blob.data, calling_blob.length);
 187         p += calling_blob.length;
 188
 189         _smb_setlen(req->out.buffer, PTR_DIFF(p, req->out.buffer)-4);
 190         SCVAL(req->out.buffer,0,0x81);
 191
 192         if (!smbcli_request_send(req)) {
 193                 smbcli_request_destroy(req);
 194                 goto failed;
 195         }
 196
 197         talloc_free(tmp_ctx);
 198         return req;
 199
 200 failed:
 201         talloc_free(tmp_ctx);
 202         return NULL;
 203 }
 204
 205 /*
 206   map a session request error to a NTSTATUS
 207  */
 208 static NTSTATUS map_session_refused_error(uint8_t error)
 209 {
 210         switch (error) {
 211         case 0x80:
 212         case 0x81:
 213                 return NT_STATUS_REMOTE_NOT_LISTENING;
 214         case 0x82:
 215                 return NT_STATUS_RESOURCE_NAME_NOT_FOUND;
 216         case 0x83:
 217                 return NT_STATUS_REMOTE_RESOURCES;
 218         }
 219         return NT_STATUS_UNEXPECTED_IO_ERROR;
 220 }
 221
 222
 223 /*
 224   finish a smbcli_transport_connect()
 225 */
 226 NTSTATUS smbcli_transport_connect_recv(struct smbcli_request *req)
 227 {
 228         NTSTATUS status;
 229
 230         if (!smbcli_request_receive(req)) {
 231                 smbcli_request_destroy(req);
 232                 return NT_STATUS_UNEXPECTED_NETWORK_ERROR;
 233         }
 234
 235         switch (CVAL(req->in.buffer,0)) {
 236         case 0x82:
 237                 status = NT_STATUS_OK;
 238                 break;
 239         case 0x83:
 240                 status = map_session_refused_error(CVAL(req->in.buffer,4));
 241                 break;
 242         case 0x84:
 243                 DEBUG(1,("Warning: session retarget not supported\n"));
 244                 status = NT_STATUS_NOT_SUPPORTED;
 245                 break;
 246         default:
 247                 status = NT_STATUS_UNEXPECTED_IO_ERROR;
 248                 break;
 249         }
 250
 251         smbcli_request_destroy(req);
 252         return status;
 253 }
 254
 255
 256 /*
 257   send a session request (if needed)
 258 */
 259 BOOL smbcli_transport_connect(struct smbcli_transport *transport,
 260                               struct nbt_name *calling,
 261                               struct nbt_name *called)
 262 {
 263         struct smbcli_request *req;
 264         NTSTATUS status;
 265
 266         if (transport->socket->port == 445) {
 267                 return True;
 268         }
 269
 270         req = smbcli_transport_connect_send(transport,
 271                                             calling, called);
 272         status = smbcli_transport_connect_recv(req);
 273         return NT_STATUS_IS_OK(status);
 274 }
 275
 276 /****************************************************************************
 277 get next mid in sequence
 278 ****************************************************************************/
 279 uint16_t smbcli_transport_next_mid(struct smbcli_transport *transport)
 280 {
 281         uint16_t mid;
 282         struct smbcli_request *req;
 283
 284         mid = transport->next_mid;
 285
 286 again:
 287         /* now check to see if this mid is being used by one of the
 288            pending requests. This is quite efficient because the list is
 289            usually very short */
 290
 291         /* the zero mid is reserved for requests that don't have a mid */
 292         if (mid == 0) mid = 1;
 293
 294         for (req=transport->pending_recv; req; req=req->next) {
 295                 if (req->mid == mid) {
 296                         mid++;
 297                         goto again;
 298                 }
 299         }
 300
 301         transport->next_mid = mid+1;
 302         return mid;
 303 }
 304
 305 static void idle_handler(struct event_context *ev,
 306                          struct timed_event *te, struct timeval t, void *private)
 307 {
 308         struct smbcli_transport *transport = talloc_get_type(private,
 309                                                              struct smbcli_transport);
 310         struct timeval next = timeval_add(&t, 0, transport->idle.period);
 311         transport->socket->event.te = event_add_timed(transport->socket->event.ctx,
 312                                                       transport,
 313                                                       next,
 314                                                       idle_handler, transport);
 315         transport->idle.func(transport, transport->idle.private);
 316 }
 317
 318 /*
 319   setup the idle handler for a transport
 320   the period is in microseconds
 321 */
 322 void smbcli_transport_idle_handler(struct smbcli_transport *transport,
 323                                    void (*idle_func)(struct smbcli_transport *, void *),
 324                                    uint64_t period,
 325                                    void *private)
 326 {
 327         transport->idle.func = idle_func;
 328         transport->idle.private = private;
 329         transport->idle.period = period;
 330
 331         if (transport->socket->event.te != NULL) {
 332                 talloc_free(transport->socket->event.te);
 333         }
 334
 335         transport->socket->event.te = event_add_timed(transport->socket->event.ctx,
 336                                                       transport,
 337                                                       timeval_current_ofs(0, period),
 338                                                       idle_handler, transport);
 339 }
 340
 341 /*
 342   process some pending sends
 343 */
 344 static void smbcli_transport_process_send(struct smbcli_transport *transport)
 345 {
 346         while (transport->pending_send) {
 347                 struct smbcli_request *req = transport->pending_send;
 348                 ssize_t ret;
 349                 ret = smbcli_sock_write(transport->socket, req->out.buffer, req->out.size);
 350                 if (ret == -1) {
 351                         if (errno == EAGAIN || errno == EINTR) {
 352                                 return;
 353                         }
 354                         smbcli_transport_dead(transport);
 355                         return;
 356                 }
 357                 req->out.buffer += ret;
 358                 req->out.size -= ret;
 359                 if (req->out.size == 0) {
 360                         DLIST_REMOVE(transport->pending_send, req);
 361                         if (req->one_way_request) {
 362                                 req->state = SMBCLI_REQUEST_DONE;
 363                                 smbcli_request_destroy(req);
 364                         } else {
 365                                 req->state = SMBCLI_REQUEST_RECV;
 366                                 DLIST_ADD(transport->pending_recv, req);
 367                         }
 368                 }
 369         }
 370
 371         /* we're out of requests to send, so don't wait for write
 372            events any more */
 373         smbcli_transport_write_disable(transport);
 374 }
 375
 376 /*
 377   we have a full request in our receive buffer - match it to a pending request
 378   and process
 379  */
 380 static void smbcli_transport_finish_recv(struct smbcli_transport *transport)
 381 {
 382         uint8_t *buffer, *hdr, *vwv;
 383         int len;
 384         uint16_t wct=0, mid = 0;
 385         struct smbcli_request *req;
 386
 387         buffer = transport->recv_buffer.buffer;
 388         len = transport->recv_buffer.req_size;
 389
 390         ZERO_STRUCT(transport->recv_buffer);
 391
 392         hdr = buffer+NBT_HDR_SIZE;
 393         vwv = hdr + HDR_VWV;
 394
 395         /* see if it could be an oplock break request */
 396         if (handle_oplock_break(transport, len, hdr, vwv)) {
 397                 talloc_free(buffer);
 398                 return;
 399         }
 400
 401         /* at this point we need to check for a readbraw reply, as
 402            these can be any length */
 403         if (transport->readbraw_pending) {
 404                 transport->readbraw_pending = 0;
 405
 406                 /* it must match the first entry in the pending queue
 407                    as the client is not allowed to have outstanding
 408                    readbraw requests */
 409                 req = transport->pending_recv;
 410                 if (!req) goto error;
 411
 412                 req->in.buffer = buffer;
 413                 talloc_steal(req, buffer);
 414                 req->in.size = len;
 415                 req->in.allocated = req->in.size;
 416                 goto async;
 417         }
 418
 419         if (len >= MIN_SMB_SIZE) {
 420                 /* extract the mid for matching to pending requests */
 421                 mid = SVAL(hdr, HDR_MID);
 422                 wct = CVAL(hdr, HDR_WCT);
 423         }
 424
 425         /* match the incoming request against the list of pending requests */
 426         for (req=transport->pending_recv; req; req=req->next) {
 427                 if (req->mid == mid) break;
 428         }
 429
 430         if (!req) {
 431                 DEBUG(1,("Discarding unmatched reply with mid %d op %d\n",
 432                          mid, CVAL(hdr, HDR_COM)));
 433                 goto error;
 434         }
 435
 436         /* fill in the 'in' portion of the matching request */
 437         req->in.buffer = buffer;
 438         talloc_steal(req, buffer);
 439         req->in.size = len;
 440         req->in.allocated = req->in.size;
 441
 442         /* handle NBT session replies */
 443         if (req->in.size >= 4 && req->in.buffer[0] != 0) {
 444                 req->status = NT_STATUS_OK;
 445                 goto async;
 446         }
 447
 448         /* handle non-SMB replies */
 449         if (req->in.size < NBT_HDR_SIZE + MIN_SMB_SIZE) {
 450                 req->state = SMBCLI_REQUEST_ERROR;
 451                 goto error;
 452         }
 453
 454         if (req->in.size < NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct)) {
 455                 DEBUG(2,("bad reply size for mid %d\n", mid));
 456                 req->status = NT_STATUS_UNSUCCESSFUL;
 457                 req->state = SMBCLI_REQUEST_ERROR;
 458                 goto error;
 459         }
 460
 461         req->in.hdr = hdr;
 462         req->in.vwv = vwv;
 463         req->in.wct = wct;
 464         if (req->in.size >= NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct)) {
 465                 req->in.data = req->in.vwv + VWV(wct) + 2;
 466                 req->in.data_size = SVAL(req->in.vwv, VWV(wct));
 467                 if (req->in.size < NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct) + req->in.data_size) {
 468                         DEBUG(3,("bad data size for mid %d\n", mid));
 469                         /* blergh - w2k3 gives a bogus data size values in some
 470                            openX replies */
 471                         req->in.data_size = req->in.size - (NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct));
 472                 }
 473         }
 474         req->in.ptr = req->in.data;
 475         req->flags2 = SVAL(req->in.hdr, HDR_FLG2);
 476
 477         if (!(req->flags2 & FLAGS2_32_BIT_ERROR_CODES)) {
 478                 transport->error.etype = ETYPE_DOS;
 479                 transport->error.e.dos.eclass = CVAL(req->in.hdr,HDR_RCLS);
 480                 transport->error.e.dos.ecode = SVAL(req->in.hdr,HDR_ERR);
 481                 req->status = dos_to_ntstatus(transport->error.e.dos.eclass,
 482                                               transport->error.e.dos.ecode);
 483         } else {
 484                 transport->error.etype = ETYPE_NT;
 485                 transport->error.e.nt_status = NT_STATUS(IVAL(req->in.hdr, HDR_RCLS));
 486                 req->status = transport->error.e.nt_status;
 487         }
 488
 489         if (!smbcli_request_check_sign_mac(req)) {
 490                 transport->error.etype = ETYPE_SOCKET;
 491                 transport->error.e.socket_error = SOCKET_READ_BAD_SIG;
 492                 req->state = SMBCLI_REQUEST_ERROR;
 493                 req->status = NT_STATUS_ACCESS_DENIED;
 494                 goto error;
 495         };
 496
 497 async:
 498         /* if this request has an async handler then call that to
 499            notify that the reply has been received. This might destroy
 500            the request so it must happen last */
 501         DLIST_REMOVE(transport->pending_recv, req);
 502         req->state = SMBCLI_REQUEST_DONE;
 503         if (req->async.fn) {
 504                 req->async.fn(req);
 505         }
 506         return;
 507
 508 error:
 509         if (req) {
 510                 DLIST_REMOVE(transport->pending_recv, req);
 511                 req->state = SMBCLI_REQUEST_ERROR;
 512         }
 513 }
 514
 515 /*
 516   process some pending receives
 517 */
 518 static void smbcli_transport_process_recv(struct smbcli_transport *transport)
 519 {
 520         /* a incoming packet goes through 2 stages - first we read the
 521            4 byte header, which tells us how much more is coming. Then
 522            we read the rest */
 523         if (transport->recv_buffer.received < NBT_HDR_SIZE) {
 524                 ssize_t ret;
 525                 ret = smbcli_sock_read(transport->socket,
 526                                     transport->recv_buffer.header +
 527                                     transport->recv_buffer.received,
 528                                     NBT_HDR_SIZE - transport->recv_buffer.received);
 529                 if (ret == -1) {
 530                         smbcli_transport_dead(transport);
 531                         return;
 532                 }
 533
 534                 transport->recv_buffer.received += ret;
 535
 536                 if (transport->recv_buffer.received == NBT_HDR_SIZE) {
 537                         /* we've got a full header */
 538                         transport->recv_buffer.req_size = smb_len(transport->recv_buffer.header) + NBT_HDR_SIZE;
 539                         transport->recv_buffer.buffer = talloc_size(transport,
 540                                                                     NBT_HDR_SIZE+transport->recv_buffer.req_size);
 541                         if (transport->recv_buffer.buffer == NULL) {
 542                                 smbcli_transport_dead(transport);
 543                                 return;
 544                         }
 545                         memcpy(transport->recv_buffer.buffer, transport->recv_buffer.header, NBT_HDR_SIZE);
 546                 }
 547         }
 548
 549         if (transport->recv_buffer.received < transport->recv_buffer.req_size) {
 550                 ssize_t ret;
 551                 ret = smbcli_sock_read(transport->socket,
 552                                     transport->recv_buffer.buffer +
 553                                     transport->recv_buffer.received,
 554                                     transport->recv_buffer.req_size -
 555                                     transport->recv_buffer.received);
 556                 if (ret == -1) {
 557                         smbcli_transport_dead(transport);
 558                         return;
 559                 }
 560                 transport->recv_buffer.received += ret;
 561         }
 562
 563         if (transport->recv_buffer.received != 0 &&
 564             transport->recv_buffer.received == transport->recv_buffer.req_size) {
 565                 smbcli_transport_finish_recv(transport);
 566         }
 567 }
 568
 569 /*
 570   process some read/write requests that are pending
 571   return False if the socket is dead
 572 */
 573 BOOL smbcli_transport_process(struct smbcli_transport *transport)
 574 {
 575         smbcli_transport_process_send(transport);
 576         smbcli_transport_process_recv(transport);
 577         if (transport->socket->sock == NULL) {
 578                 return False;
 579         }
 580         return True;
 581 }
 582
 583
 584
 585 /*
 586   put a request into the send queue
 587 */
 588 void smbcli_transport_send(struct smbcli_request *req)
 589 {
 590         /* check if the transport is dead */
 591         if (req->transport->socket->sock == NULL) {
 592                 req->state = SMBCLI_REQUEST_ERROR;
 593                 req->status = NT_STATUS_NET_WRITE_FAULT;
 594                 return;
 595         }
 596
 597         /* put it on the outgoing socket queue */
 598         req->state = SMBCLI_REQUEST_SEND;
 599         DLIST_ADD_END(req->transport->pending_send, req, struct smbcli_request *);
 600
 601         /* make sure we look for write events */
 602         smbcli_transport_write_enable(req->transport);
 603 }