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