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