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