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