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