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