source4/libcli/raw/clitransport.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    SMB client transport context management functions
   4    Copyright (C) Andrew Tridgell 1994-2003
   5    Copyright (C) James Myers 2003 <myersjj@samba.org>
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23 #include "libcli/raw/libcliraw.h"
  24 #include "system/time.h"
  25 #include "dlinklist.h"
  26 #include "events.h"
  27
  28
  29 static void smbcli_transport_process_recv(struct smbcli_transport *transport);
  30 static void smbcli_transport_process_send(struct smbcli_transport *transport);
  31
  32 /*
  33   an event has happened on the socket
  34 */
  35 static void smbcli_transport_event_handler(struct event_context *ev, struct fd_event *fde,
  36                                            struct timeval t, uint16_t flags)
  37 {
  38         struct smbcli_transport *transport = fde->private;
  39
  40         if (flags & EVENT_FD_READ) {
  41                 smbcli_transport_process_recv(transport);
  42         }
  43         if (flags & EVENT_FD_WRITE) {
  44                 smbcli_transport_process_send(transport);
  45         }
  46 }
  47
  48 /*
  49   destroy a transport
  50  */
  51 static int transport_destructor(void *ptr)
  52 {
  53         struct smbcli_transport *transport = ptr;
  54
  55         smbcli_transport_dead(transport);
  56         event_remove_fd(transport->socket->event.ctx, transport->socket->event.fde);
  57         event_remove_timed(transport->socket->event.ctx, transport->socket->event.te);
  58         return 0;
  59 }
  60
  61 /*
  62   create a transport structure based on an established socket
  63 */
  64 struct smbcli_transport *smbcli_transport_init(struct smbcli_socket *sock)
  65 {
  66         struct smbcli_transport *transport;
  67
  68         transport = talloc_p(sock, struct smbcli_transport);
  69         if (!transport) return NULL;
  70
  71         ZERO_STRUCTP(transport);
  72
  73         transport->socket = talloc_reference(transport, sock);
  74         transport->negotiate.protocol = PROTOCOL_NT1;
  75         transport->options.use_spnego = lp_use_spnego();
  76         transport->options.max_xmit = lp_max_xmit();
  77         transport->options.max_mux = lp_maxmux();
  78
  79         transport->negotiate.max_xmit = transport->options.max_xmit;
  80
  81         smbcli_init_signing(transport);
  82
  83         ZERO_STRUCT(transport->called);
  84
  85         /* take over event handling from the socket layer - it only
  86            handles events up until we are connected */
  87         transport->socket->event.fde->handler = smbcli_transport_event_handler;
  88         transport->socket->event.fde->private = transport;
  89         transport->socket->event.fde->flags = EVENT_FD_READ;
  90
  91         talloc_set_destructor(transport, transport_destructor);
  92
  93         return transport;
  94 }
  95
  96 /*
  97   mark the transport as dead
  98 */
  99 void smbcli_transport_dead(struct smbcli_transport *transport)
 100 {
 101         smbcli_sock_dead(transport->socket);
 102
 103         /* all pending sends become errors */
 104         while (transport->pending_send) {
 105                 struct smbcli_request *req = transport->pending_send;
 106                 req->state = SMBCLI_REQUEST_ERROR;
 107                 req->status = NT_STATUS_NET_WRITE_FAULT;
 108                 DLIST_REMOVE(transport->pending_send, req);
 109                 if (req->async.fn) {
 110                         req->async.fn(req);
 111                 }
 112         }
 113
 114         /* as do all pending receives */
 115         while (transport->pending_recv) {
 116                 struct smbcli_request *req = transport->pending_recv;
 117                 req->state = SMBCLI_REQUEST_ERROR;
 118                 req->status = NT_STATUS_NET_WRITE_FAULT;
 119                 DLIST_REMOVE(transport->pending_recv, req);
 120                 if (req->async.fn) {
 121                         req->async.fn(req);
 122                 }
 123         }
 124 }
 125
 126
 127 /*
 128   enable select for write on a transport
 129 */
 130 static void smbcli_transport_write_enable(struct smbcli_transport *transport)
 131 {
 132         transport->socket->event.fde->flags |= EVENT_FD_WRITE;
 133 }
 134
 135 /*
 136   disable select for write on a transport
 137 */
 138 static void smbcli_transport_write_disable(struct smbcli_transport *transport)
 139 {
 140         transport->socket->event.fde->flags &= ~EVENT_FD_WRITE;
 141 }
 142
 143 /*
 144   send a session request
 145 */
 146 struct smbcli_request *smbcli_transport_connect_send(struct smbcli_transport *transport,
 147                                                      struct nmb_name *calling,
 148                                                      struct nmb_name *called)
 149 {
 150         uint8_t *p;
 151         int len = NBT_HDR_SIZE;
 152         struct smbcli_request *req;
 153
 154         if (called) {
 155                 transport->called = *called;
 156         }
 157
 158         /* allocate output buffer */
 159         req = smbcli_request_setup_nonsmb(transport,
 160                                           NBT_HDR_SIZE + 2*nbt_mangled_name_len());
 161         if (req == NULL) return NULL;
 162
 163         /* put in the destination name */
 164         p = req->out.buffer + NBT_HDR_SIZE;
 165         name_mangle(called->name, (char *)p, called->name_type);
 166         len += name_len((char *)p);
 167
 168         /* and my name */
 169         p = req->out.buffer+len;
 170         name_mangle(calling->name, (char *)p, calling->name_type);
 171         len += name_len((char *)p);
 172
 173         _smb_setlen(req->out.buffer,len-4);
 174         SCVAL(req->out.buffer,0,0x81);
 175
 176         if (!smbcli_request_send(req)) {
 177                 smbcli_request_destroy(req);
 178                 return NULL;
 179         }
 180
 181         return req;
 182 }
 183
 184 /*
 185   finish a smbcli_transport_connect()
 186 */
 187 BOOL smbcli_transport_connect_recv(struct smbcli_request *req)
 188 {
 189         if (!smbcli_request_receive(req)) {
 190                 smbcli_request_destroy(req);
 191                 return False;
 192         }
 193
 194         if (CVAL(req->in.buffer,0) != 0x82) {
 195                 req->transport->error.etype = ETYPE_NBT;
 196                 req->transport->error.e.nbt_error = CVAL(req->in.buffer,4);
 197                 smbcli_request_destroy(req);
 198                 return False;
 199         }
 200
 201         smbcli_request_destroy(req);
 202         return True;
 203 }
 204
 205
 206 /*
 207   send a session request (if needed)
 208 */
 209 BOOL smbcli_transport_connect(struct smbcli_transport *transport,
 210                               struct nmb_name *calling,
 211                               struct nmb_name *called)
 212 {
 213         struct smbcli_request *req;
 214
 215         if (transport->socket->port == 445) {
 216                 return True;
 217         }
 218
 219         req = smbcli_transport_connect_send(transport,
 220                                             calling, called);
 221         return smbcli_transport_connect_recv(req);
 222 }
 223
 224 /****************************************************************************
 225 get next mid in sequence
 226 ****************************************************************************/
 227 uint16_t smbcli_transport_next_mid(struct smbcli_transport *transport)
 228 {
 229         uint16_t mid;
 230         struct smbcli_request *req;
 231
 232         mid = transport->next_mid;
 233
 234 again:
 235         /* now check to see if this mid is being used by one of the
 236            pending requests. This is quite efficient because the list is
 237            usually very short */
 238
 239         /* the zero mid is reserved for requests that don't have a mid */
 240         if (mid == 0) mid = 1;
 241
 242         for (req=transport->pending_recv; req; req=req->next) {
 243                 if (req->mid == mid) {
 244                         mid++;
 245                         goto again;
 246                 }
 247         }
 248
 249         transport->next_mid = mid+1;
 250         return mid;
 251 }
 252
 253 static void idle_handler(struct event_context *ev,
 254                          struct timed_event *te, struct timeval t)
 255 {
 256         struct smbcli_transport *transport = te->private;
 257         te->next_event = timeval_add(&te->next_event, 0, transport->idle.period);
 258         transport->idle.func(transport, transport->idle.private);
 259 }
 260
 261 /*
 262   setup the idle handler for a transport
 263   the period is in microseconds
 264 */
 265 void smbcli_transport_idle_handler(struct smbcli_transport *transport,
 266                                    void (*idle_func)(struct smbcli_transport *, void *),
 267                                    uint64_t period,
 268                                    void *private)
 269 {
 270         struct timed_event te;
 271         transport->idle.func = idle_func;
 272         transport->idle.private = private;
 273         transport->idle.period = period;
 274
 275         if (transport->socket->event.te != NULL) {
 276                 event_remove_timed(transport->socket->event.ctx, transport->socket->event.te);
 277         }
 278
 279         te.next_event = timeval_current_ofs(0, period);
 280         te.handler = idle_handler;
 281         te.private = transport;
 282         transport->socket->event.te = event_add_timed(transport->socket->event.ctx, &te);
 283 }
 284
 285 /*
 286   process some pending sends
 287 */
 288 static void smbcli_transport_process_send(struct smbcli_transport *transport)
 289 {
 290         while (transport->pending_send) {
 291                 struct smbcli_request *req = transport->pending_send;
 292                 ssize_t ret;
 293                 ret = smbcli_sock_write(transport->socket, req->out.buffer, req->out.size);
 294                 if (ret == -1) {
 295                         if (errno == EAGAIN || errno == EINTR) {
 296                                 return;
 297                         }
 298                         smbcli_transport_dead(transport);
 299                         return;
 300                 }
 301                 req->out.buffer += ret;
 302                 req->out.size -= ret;
 303                 if (req->out.size == 0) {
 304                         DLIST_REMOVE(transport->pending_send, req);
 305                         if (req->one_way_request) {
 306                                 req->state = SMBCLI_REQUEST_DONE;
 307                                 smbcli_request_destroy(req);
 308                         } else {
 309                                 req->state = SMBCLI_REQUEST_RECV;
 310                                 DLIST_ADD(transport->pending_recv, req);
 311                         }
 312                 }
 313         }
 314
 315         /* we're out of requests to send, so don't wait for write
 316            events any more */
 317         smbcli_transport_write_disable(transport);
 318 }
 319
 320 /*
 321   we have a full request in our receive buffer - match it to a pending request
 322   and process
 323  */
 324 static void smbcli_transport_finish_recv(struct smbcli_transport *transport)
 325 {
 326         uint8_t *buffer, *hdr, *vwv;
 327         int len;
 328         uint16_t wct=0, mid = 0;
 329         struct smbcli_request *req;
 330
 331         buffer = transport->recv_buffer.buffer;
 332         len = transport->recv_buffer.req_size;
 333
 334         ZERO_STRUCT(transport->recv_buffer);
 335
 336         hdr = buffer+NBT_HDR_SIZE;
 337         vwv = hdr + HDR_VWV;
 338
 339         /* see if it could be an oplock break request */
 340         if (handle_oplock_break(transport, len, hdr, vwv)) {
 341                 talloc_free(buffer);
 342                 return;
 343         }
 344
 345         /* at this point we need to check for a readbraw reply, as
 346            these can be any length */
 347         if (transport->readbraw_pending) {
 348                 transport->readbraw_pending = 0;
 349
 350                 /* it must match the first entry in the pending queue
 351                    as the client is not allowed to have outstanding
 352                    readbraw requests */
 353                 req = transport->pending_recv;
 354                 if (!req) goto error;
 355
 356                 req->in.buffer = buffer;
 357                 talloc_steal(req, buffer);
 358                 req->in.size = len;
 359                 req->in.allocated = req->in.size;
 360                 goto async;
 361         }
 362
 363         if (len >= MIN_SMB_SIZE) {
 364                 /* extract the mid for matching to pending requests */
 365                 mid = SVAL(hdr, HDR_MID);
 366                 wct = CVAL(hdr, HDR_WCT);
 367         }
 368
 369         /* match the incoming request against the list of pending requests */
 370         for (req=transport->pending_recv; req; req=req->next) {
 371                 if (req->mid == mid) break;
 372         }
 373
 374         if (!req) {
 375                 DEBUG(1,("Discarding unmatched reply with mid %d op %d\n",
 376                          mid, CVAL(hdr, HDR_COM)));
 377                 goto error;
 378         }
 379
 380         /* fill in the 'in' portion of the matching request */
 381         req->in.buffer = buffer;
 382         talloc_steal(req, buffer);
 383         req->in.size = len;
 384         req->in.allocated = req->in.size;
 385
 386         /* handle NBT session replies */
 387         if (req->in.size >= 4 && req->in.buffer[0] != 0) {
 388                 req->status = NT_STATUS_OK;
 389                 goto async;
 390         }
 391
 392         /* handle non-SMB replies */
 393         if (req->in.size < NBT_HDR_SIZE + MIN_SMB_SIZE) {
 394                 req->state = SMBCLI_REQUEST_ERROR;
 395                 goto error;
 396         }
 397
 398         if (req->in.size < NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct)) {
 399                 DEBUG(2,("bad reply size for mid %d\n", mid));
 400                 req->status = NT_STATUS_UNSUCCESSFUL;
 401                 req->state = SMBCLI_REQUEST_ERROR;
 402                 goto error;
 403         }
 404
 405         req->in.hdr = hdr;
 406         req->in.vwv = vwv;
 407         req->in.wct = wct;
 408         if (req->in.size >= NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct)) {
 409                 req->in.data = req->in.vwv + VWV(wct) + 2;
 410                 req->in.data_size = SVAL(req->in.vwv, VWV(wct));
 411                 if (req->in.size < NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct) + req->in.data_size) {
 412                         DEBUG(3,("bad data size for mid %d\n", mid));
 413                         /* blergh - w2k3 gives a bogus data size values in some
 414                            openX replies */
 415                         req->in.data_size = req->in.size - (NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct));
 416                 }
 417         }
 418         req->in.ptr = req->in.data;
 419         req->flags2 = SVAL(req->in.hdr, HDR_FLG2);
 420
 421         if (!(req->flags2 & FLAGS2_32_BIT_ERROR_CODES)) {
 422                 transport->error.etype = ETYPE_DOS;
 423                 transport->error.e.dos.eclass = CVAL(req->in.hdr,HDR_RCLS);
 424                 transport->error.e.dos.ecode = SVAL(req->in.hdr,HDR_ERR);
 425                 req->status = dos_to_ntstatus(transport->error.e.dos.eclass,
 426                                               transport->error.e.dos.ecode);
 427         } else {
 428                 transport->error.etype = ETYPE_NT;
 429                 transport->error.e.nt_status = NT_STATUS(IVAL(req->in.hdr, HDR_RCLS));
 430                 req->status = transport->error.e.nt_status;
 431         }
 432
 433         if (!smbcli_request_check_sign_mac(req)) {
 434                 transport->error.etype = ETYPE_SOCKET;
 435                 transport->error.e.socket_error = SOCKET_READ_BAD_SIG;
 436                 req->state = SMBCLI_REQUEST_ERROR;
 437                 req->status = NT_STATUS_ACCESS_DENIED;
 438                 goto error;
 439         };
 440
 441 async:
 442         /* if this request has an async handler then call that to
 443            notify that the reply has been received. This might destroy
 444            the request so it must happen last */
 445         DLIST_REMOVE(transport->pending_recv, req);
 446         req->state = SMBCLI_REQUEST_DONE;
 447         if (req->async.fn) {
 448                 req->async.fn(req);
 449         }
 450         return;
 451
 452 error:
 453         if (req) {
 454                 DLIST_REMOVE(transport->pending_recv, req);
 455                 req->state = SMBCLI_REQUEST_ERROR;
 456         }
 457 }
 458
 459 /*
 460   process some pending receives
 461 */
 462 static void smbcli_transport_process_recv(struct smbcli_transport *transport)
 463 {
 464         /* a incoming packet goes through 2 stages - first we read the
 465            4 byte header, which tells us how much more is coming. Then
 466            we read the rest */
 467         if (transport->recv_buffer.received < NBT_HDR_SIZE) {
 468                 ssize_t ret;
 469                 ret = smbcli_sock_read(transport->socket,
 470                                     transport->recv_buffer.header +
 471                                     transport->recv_buffer.received,
 472                                     NBT_HDR_SIZE - transport->recv_buffer.received);
 473                 if (ret == -1) {
 474                         smbcli_transport_dead(transport);
 475                         return;
 476                 }
 477
 478                 transport->recv_buffer.received += ret;
 479
 480                 if (transport->recv_buffer.received == NBT_HDR_SIZE) {
 481                         /* we've got a full header */
 482                         transport->recv_buffer.req_size = smb_len(transport->recv_buffer.header) + NBT_HDR_SIZE;
 483                         transport->recv_buffer.buffer = talloc_size(transport,
 484                                                                     NBT_HDR_SIZE+transport->recv_buffer.req_size);
 485                         if (transport->recv_buffer.buffer == NULL) {
 486                                 smbcli_transport_dead(transport);
 487                                 return;
 488                         }
 489                         memcpy(transport->recv_buffer.buffer, transport->recv_buffer.header, NBT_HDR_SIZE);
 490                 }
 491         }
 492
 493         if (transport->recv_buffer.received < transport->recv_buffer.req_size) {
 494                 ssize_t ret;
 495                 ret = smbcli_sock_read(transport->socket,
 496                                     transport->recv_buffer.buffer +
 497                                     transport->recv_buffer.received,
 498                                     transport->recv_buffer.req_size -
 499                                     transport->recv_buffer.received);
 500                 if (ret == -1) {
 501                         smbcli_transport_dead(transport);
 502                         return;
 503                 }
 504                 transport->recv_buffer.received += ret;
 505         }
 506
 507         if (transport->recv_buffer.received != 0 &&
 508             transport->recv_buffer.received == transport->recv_buffer.req_size) {
 509                 smbcli_transport_finish_recv(transport);
 510         }
 511 }
 512
 513 /*
 514   process some read/write requests that are pending
 515   return False if the socket is dead
 516 */
 517 BOOL smbcli_transport_process(struct smbcli_transport *transport)
 518 {
 519         smbcli_transport_process_send(transport);
 520         smbcli_transport_process_recv(transport);
 521         if (transport->socket->sock == NULL) {
 522                 return False;
 523         }
 524         return True;
 525 }
 526
 527
 528
 529 /*
 530   put a request into the send queue
 531 */
 532 void smbcli_transport_send(struct smbcli_request *req)
 533 {
 534         /* check if the transport is dead */
 535         if (req->transport->socket->sock == NULL) {
 536                 req->state = SMBCLI_REQUEST_ERROR;
 537                 req->status = NT_STATUS_NET_WRITE_FAULT;
 538                 return;
 539         }
 540
 541         /* put it on the outgoing socket queue */
 542         req->state = SMBCLI_REQUEST_SEND;
 543         DLIST_ADD_END(req->transport->pending_send, req, struct smbcli_request *);
 544
 545         /* make sure we look for write events */
 546         smbcli_transport_write_enable(req->transport);
 547 }