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