source3/smbd/process.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    process incoming packets - main loop
   4    Copyright (C) Andrew Tridgell 1992-1998
   5    Copyright (C) Volker Lendecke 2005-2007
   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 3 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, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22
  23 extern struct auth_context *negprot_global_auth_context;
  24 extern int smb_echo_count;
  25
  26 const int total_buffer_size = (BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE + SAFETY_MARGIN);
  27 static enum smb_read_errors smb_read_error = SMB_READ_OK;
  28
  29 /*
  30  * Size of data we can send to client. Set
  31  *  by the client for all protocols above CORE.
  32  *  Set by us for CORE protocol.
  33  */
  34 int max_send = BUFFER_SIZE;
  35 /*
  36  * Size of the data we can receive. Set by us.
  37  * Can be modified by the max xmit parameter.
  38  */
  39 int max_recv = BUFFER_SIZE;
  40
  41 SIG_ATOMIC_T reload_after_sighup = 0;
  42 SIG_ATOMIC_T got_sig_term = 0;
  43 extern bool global_machine_password_needs_changing;
  44 extern int max_send;
  45
  46 /* Accessor function for smb_read_error for smbd functions. */
  47
  48 enum smb_read_errors *get_srv_read_error(void)
  49 {
  50         return &smb_read_error;
  51 }
  52
  53 /* Socket functions for smbd packet processing. */
  54
  55 static bool valid_packet_size(size_t len)
  56 {
  57         /*
  58          * A WRITEX with CAP_LARGE_WRITEX can be 64k worth of data plus 65 bytes
  59          * of header. Don't print the error if this fits.... JRA.
  60          */
  61
  62         if (len > (BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE)) {
  63                 DEBUG(0,("Invalid packet length! (%lu bytes).\n",
  64                                         (unsigned long)len));
  65                 if (len > BUFFER_SIZE + (SAFETY_MARGIN/2)) {
  66
  67                         /*
  68                          * Correct fix. smb_read_error may have already been
  69                          * set. Only set it here if not already set. Global
  70                          * variables still suck :-). JRA.
  71                          */
  72
  73                         cond_set_smb_read_error(get_srv_read_error(),
  74                                                 SMB_READ_ERROR);
  75                         return false;
  76                 }
  77         }
  78         return true;
  79 }
  80
  81 static ssize_t read_packet_remainder(int fd,
  82                                         char *buffer,
  83                                         unsigned int timeout,
  84                                         ssize_t len)
  85 {
  86         ssize_t ret;
  87
  88         if(len <= 0) {
  89                 return len;
  90         }
  91
  92         if (timeout > 0) {
  93                 ret = read_socket_with_timeout(fd,
  94                                                 buffer,
  95                                                 len,
  96                                                 len,
  97                                                 timeout,
  98                                                 get_srv_read_error());
  99         } else {
 100                 ret = read_data(fd, buffer, len, get_srv_read_error());
 101         }
 102
 103         if (ret != len) {
 104                 cond_set_smb_read_error(get_srv_read_error(),
 105                                         SMB_READ_ERROR);
 106                 return -1;
 107         }
 108
 109         return len;
 110 }
 111
 112 /****************************************************************************
 113  Attempt a zerocopy writeX read. We know here that len > smb_size-4
 114 ****************************************************************************/
 115
 116 /*
 117  * Unfortunately, earlier versions of smbclient/libsmbclient
 118  * don't send this "standard" writeX header. I've fixed this
 119  * for 3.2 but we'll use the old method with earlier versions.
 120  * Windows and CIFSFS at least use this standard size. Not
 121  * sure about MacOSX.
 122  */
 123
 124 #define STANDARD_WRITE_AND_X_HEADER_SIZE (smb_size - 4 + /* basic header */ \
 125                                 (2*14) + /* word count (including bcc) */ \
 126                                 1 /* pad byte */)
 127
 128 ssize_t receive_smb_raw_talloc_partial_read(TALLOC_CTX *mem_ctx,
 129                                         const char lenbuf[4],
 130                                         int fd,
 131                                         char **buffer,
 132                                         unsigned int timeout,
 133                                         size_t *p_unread)
 134 {
 135         /* Size of a WRITEX call (+4 byte len). */
 136         char writeX_header[4 + STANDARD_WRITE_AND_X_HEADER_SIZE];
 137         ssize_t len = smb_len_large(lenbuf); /* Could be a UNIX large writeX. */
 138         ssize_t toread;
 139         ssize_t ret;
 140
 141         memcpy(writeX_header, lenbuf, sizeof(lenbuf));
 142
 143         if (timeout > 0) {
 144                 ret = read_socket_with_timeout(fd,
 145                                         writeX_header + 4,
 146                                         STANDARD_WRITE_AND_X_HEADER_SIZE,
 147                                         STANDARD_WRITE_AND_X_HEADER_SIZE,
 148                                         timeout,
 149                                         get_srv_read_error());
 150         } else {
 151                 ret = read_data(fd,
 152                                 writeX_header+4,
 153                                 STANDARD_WRITE_AND_X_HEADER_SIZE,
 154                                 get_srv_read_error());
 155         }
 156
 157         if (ret != STANDARD_WRITE_AND_X_HEADER_SIZE) {
 158                 cond_set_smb_read_error(get_srv_read_error(),
 159                                         SMB_READ_ERROR);
 160                 return -1;
 161         }
 162
 163         /*
 164          * Ok - now try and see if this is a possible
 165          * valid writeX call.
 166          */
 167
 168         if (is_valid_writeX_buffer(writeX_header)) {
 169                 /*
 170                  * If the data offset is beyond what
 171                  * we've read, drain the extra bytes.
 172                  */
 173                 uint16_t doff = SVAL(writeX_header,smb_vwv11);
 174                 ssize_t newlen;
 175
 176                 if (doff > STANDARD_WRITE_AND_X_HEADER_SIZE) {
 177                         size_t drain = doff - STANDARD_WRITE_AND_X_HEADER_SIZE;
 178                         if (drain_socket(smbd_server_fd(), drain) != drain) {
 179                                 smb_panic("receive_smb_raw_talloc_partial_read:"
 180                                         " failed to drain pending bytes");
 181                         }
 182                 } else {
 183                         doff = STANDARD_WRITE_AND_X_HEADER_SIZE;
 184                 }
 185
 186                 /* Spoof down the length and null out the bcc. */
 187                 set_message_bcc(writeX_header, 0);
 188                 newlen = smb_len(writeX_header);
 189
 190                 /* Copy the header we've written. */
 191
 192                 *buffer = (char *)TALLOC_MEMDUP(mem_ctx,
 193                                 writeX_header,
 194                                 sizeof(writeX_header));
 195
 196                 if (*buffer == NULL) {
 197                         DEBUG(0, ("Could not allocate inbuf of length %d\n",
 198                                   (int)sizeof(writeX_header)));
 199                         cond_set_smb_read_error(get_srv_read_error(),
 200                                                 SMB_READ_ERROR);
 201                         return -1;
 202                 }
 203
 204                 /* Work out the remaining bytes. */
 205                 *p_unread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
 206
 207                 return newlen + 4;
 208         }
 209
 210         if (!valid_packet_size(len)) {
 211                 return -1;
 212         }
 213
 214         /*
 215          * Not a valid writeX call. Just do the standard
 216          * talloc and return.
 217          */
 218
 219         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
 220
 221         if (*buffer == NULL) {
 222                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
 223                           (int)len+4));
 224                 cond_set_smb_read_error(get_srv_read_error(),
 225                                         SMB_READ_ERROR);
 226                 return -1;
 227         }
 228
 229         /* Copy in what we already read. */
 230         memcpy(*buffer,
 231                 writeX_header,
 232                 4 + STANDARD_WRITE_AND_X_HEADER_SIZE);
 233         toread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
 234
 235         if(toread > 0) {
 236                 ret = read_packet_remainder(fd,
 237                         (*buffer) + 4 + STANDARD_WRITE_AND_X_HEADER_SIZE,
 238                                         timeout,
 239                                         toread);
 240                 if (ret != toread) {
 241                         return -1;
 242                 }
 243         }
 244
 245         return len + 4;
 246 }
 247
 248 static ssize_t receive_smb_raw_talloc(TALLOC_CTX *mem_ctx,
 249                                         int fd,
 250                                         char **buffer,
 251                                         unsigned int timeout,
 252                                         size_t *p_unread)
 253 {
 254         char lenbuf[4];
 255         ssize_t len,ret;
 256         int min_recv_size = lp_min_receive_file_size();
 257
 258         set_smb_read_error(get_srv_read_error(),SMB_READ_OK);
 259         *p_unread = 0;
 260
 261         len = read_smb_length_return_keepalive(fd, lenbuf,
 262                         timeout, get_srv_read_error());
 263         if (len < 0) {
 264                 DEBUG(10,("receive_smb_raw: length < 0!\n"));
 265
 266                 /*
 267                  * Correct fix. smb_read_error may have already been
 268                  * set. Only set it here if not already set. Global
 269                  * variables still suck :-). JRA.
 270                  */
 271
 272                 cond_set_smb_read_error(get_srv_read_error(),SMB_READ_ERROR);
 273                 return -1;
 274         }
 275
 276         if (CVAL(lenbuf,0) != SMBkeepalive &&
 277                         min_recv_size &&
 278                         smb_len_large(lenbuf) > min_recv_size && /* Could be a UNIX large writeX. */
 279                         !srv_is_signing_active()) {
 280
 281                 return receive_smb_raw_talloc_partial_read(mem_ctx,
 282                                                         lenbuf,
 283                                                         fd,
 284                                                         buffer,
 285                                                         timeout,
 286                                                         p_unread);
 287         }
 288
 289         if (!valid_packet_size(len)) {
 290                 return -1;
 291         }
 292
 293         /*
 294          * The +4 here can't wrap, we've checked the length above already.
 295          */
 296
 297         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
 298
 299         if (*buffer == NULL) {
 300                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
 301                           (int)len+4));
 302                 cond_set_smb_read_error(get_srv_read_error(),SMB_READ_ERROR);
 303                 return -1;
 304         }
 305
 306         memcpy(*buffer, lenbuf, sizeof(lenbuf));
 307
 308         ret = read_packet_remainder(fd, (*buffer)+4, timeout, len);
 309         if (ret != len) {
 310                 return -1;
 311         }
 312
 313         return len + 4;
 314 }
 315
 316 ssize_t receive_smb_talloc(TALLOC_CTX *mem_ctx, int fd, char **buffer,
 317                            unsigned int timeout, size_t *p_unread)
 318 {
 319         ssize_t len;
 320
 321         len = receive_smb_raw_talloc(mem_ctx, fd, buffer, timeout, p_unread);
 322
 323         if (len < 0) {
 324                 return -1;
 325         }
 326
 327         /* Check the incoming SMB signature. */
 328         if (!srv_check_sign_mac(*buffer, true)) {
 329                 DEBUG(0, ("receive_smb: SMB Signature verification failed on "
 330                           "incoming packet!\n"));
 331                 cond_set_smb_read_error(get_srv_read_error(),SMB_READ_BAD_SIG);
 332                 return -1;
 333         }
 334
 335         return len;
 336 }
 337
 338 /*
 339  * Initialize a struct smb_request from an inbuf
 340  */
 341
 342 void init_smb_request(struct smb_request *req,
 343                         const uint8 *inbuf,
 344                         size_t unread_bytes)
 345 {
 346         size_t req_size = smb_len(inbuf) + 4;
 347         /* Ensure we have at least smb_size bytes. */
 348         if (req_size < smb_size) {
 349                 DEBUG(0,("init_smb_request: invalid request size %u\n",
 350                         (unsigned int)req_size ));
 351                 exit_server_cleanly("Invalid SMB request");
 352         }
 353         req->flags2 = SVAL(inbuf, smb_flg2);
 354         req->smbpid = SVAL(inbuf, smb_pid);
 355         req->mid    = SVAL(inbuf, smb_mid);
 356         req->vuid   = SVAL(inbuf, smb_uid);
 357         req->tid    = SVAL(inbuf, smb_tid);
 358         req->wct    = CVAL(inbuf, smb_wct);
 359         req->unread_bytes = unread_bytes;
 360
 361         /* Ensure we have at least wct words and 2 bytes of bcc. */
 362         if (smb_size + req->wct*2 > req_size) {
 363                 DEBUG(0,("init_smb_request: invalid wct number %u (size %u)\n",
 364                         (unsigned int)req->wct,
 365                         (unsigned int)req_size));
 366                 exit_server_cleanly("Invalid SMB request");
 367         }
 368         /* Ensure bcc is correct. */
 369         if (((uint8 *)smb_buf(inbuf)) + smb_buflen(inbuf) > inbuf + req_size) {
 370                 DEBUG(0,("init_smb_request: invalid bcc number %u "
 371                         "(wct = %u, size %u)\n",
 372                         (unsigned int)smb_buflen(inbuf),
 373                         (unsigned int)req->wct,
 374                         (unsigned int)req_size));
 375                 exit_server_cleanly("Invalid SMB request");
 376         }
 377         req->inbuf  = inbuf;
 378         req->outbuf = NULL;
 379 }
 380
 381 /****************************************************************************
 382  structure to hold a linked list of queued messages.
 383  for processing.
 384 ****************************************************************************/
 385
 386 static struct pending_message_list *deferred_open_queue;
 387
 388 /****************************************************************************
 389  Function to push a message onto the tail of a linked list of smb messages ready
 390  for processing.
 391 ****************************************************************************/
 392
 393 static bool push_queued_message(struct smb_request *req,
 394                                 struct timeval request_time,
 395                                 struct timeval end_time,
 396                                 char *private_data, size_t private_len)
 397 {
 398         int msg_len = smb_len(req->inbuf) + 4;
 399         struct pending_message_list *msg;
 400
 401         msg = TALLOC_ZERO_P(NULL, struct pending_message_list);
 402
 403         if(msg == NULL) {
 404                 DEBUG(0,("push_message: malloc fail (1)\n"));
 405                 return False;
 406         }
 407
 408         msg->buf = data_blob_talloc(msg, req->inbuf, msg_len);
 409         if(msg->buf.data == NULL) {
 410                 DEBUG(0,("push_message: malloc fail (2)\n"));
 411                 TALLOC_FREE(msg);
 412                 return False;
 413         }
 414
 415         msg->request_time = request_time;
 416         msg->end_time = end_time;
 417
 418         if (private_data) {
 419                 msg->private_data = data_blob_talloc(msg, private_data,
 420                                                      private_len);
 421                 if (msg->private_data.data == NULL) {
 422                         DEBUG(0,("push_message: malloc fail (3)\n"));
 423                         TALLOC_FREE(msg);
 424                         return False;
 425                 }
 426         }
 427
 428         DLIST_ADD_END(deferred_open_queue, msg, struct pending_message_list *);
 429
 430         DEBUG(10,("push_message: pushed message length %u on "
 431                   "deferred_open_queue\n", (unsigned int)msg_len));
 432
 433         return True;
 434 }
 435
 436 /****************************************************************************
 437  Function to delete a sharing violation open message by mid.
 438 ****************************************************************************/
 439
 440 void remove_deferred_open_smb_message(uint16 mid)
 441 {
 442         struct pending_message_list *pml;
 443
 444         for (pml = deferred_open_queue; pml; pml = pml->next) {
 445                 if (mid == SVAL(pml->buf.data,smb_mid)) {
 446                         DEBUG(10,("remove_sharing_violation_open_smb_message: "
 447                                   "deleting mid %u len %u\n",
 448                                   (unsigned int)mid,
 449                                   (unsigned int)pml->buf.length ));
 450                         DLIST_REMOVE(deferred_open_queue, pml);
 451                         TALLOC_FREE(pml);
 452                         return;
 453                 }
 454         }
 455 }
 456
 457 /****************************************************************************
 458  Move a sharing violation open retry message to the front of the list and
 459  schedule it for immediate processing.
 460 ****************************************************************************/
 461
 462 void schedule_deferred_open_smb_message(uint16 mid)
 463 {
 464         struct pending_message_list *pml;
 465         int i = 0;
 466
 467         for (pml = deferred_open_queue; pml; pml = pml->next) {
 468                 uint16 msg_mid = SVAL(pml->buf.data,smb_mid);
 469                 DEBUG(10,("schedule_deferred_open_smb_message: [%d] msg_mid = %u\n", i++,
 470                         (unsigned int)msg_mid ));
 471                 if (mid == msg_mid) {
 472                         DEBUG(10,("schedule_deferred_open_smb_message: scheduling mid %u\n",
 473                                 mid ));
 474                         pml->end_time.tv_sec = 0;
 475                         pml->end_time.tv_usec = 0;
 476                         DLIST_PROMOTE(deferred_open_queue, pml);
 477                         return;
 478                 }
 479         }
 480
 481         DEBUG(10,("schedule_deferred_open_smb_message: failed to find message mid %u\n",
 482                 mid ));
 483 }
 484
 485 /****************************************************************************
 486  Return true if this mid is on the deferred queue.
 487 ****************************************************************************/
 488
 489 bool open_was_deferred(uint16 mid)
 490 {
 491         struct pending_message_list *pml;
 492
 493         for (pml = deferred_open_queue; pml; pml = pml->next) {
 494                 if (SVAL(pml->buf.data,smb_mid) == mid) {
 495                         return True;
 496                 }
 497         }
 498         return False;
 499 }
 500
 501 /****************************************************************************
 502  Return the message queued by this mid.
 503 ****************************************************************************/
 504
 505 struct pending_message_list *get_open_deferred_message(uint16 mid)
 506 {
 507         struct pending_message_list *pml;
 508
 509         for (pml = deferred_open_queue; pml; pml = pml->next) {
 510                 if (SVAL(pml->buf.data,smb_mid) == mid) {
 511                         return pml;
 512                 }
 513         }
 514         return NULL;
 515 }
 516
 517 /****************************************************************************
 518  Function to push a deferred open smb message onto a linked list of local smb
 519  messages ready for processing.
 520 ****************************************************************************/
 521
 522 bool push_deferred_smb_message(struct smb_request *req,
 523                                struct timeval request_time,
 524                                struct timeval timeout,
 525                                char *private_data, size_t priv_len)
 526 {
 527         struct timeval end_time;
 528
 529         if (req->unread_bytes) {
 530                 DEBUG(0,("push_deferred_smb_message: logic error ! "
 531                         "unread_bytes = %u\n",
 532                         (unsigned int)req->unread_bytes ));
 533                 smb_panic("push_deferred_smb_message: "
 534                         "logic error unread_bytes != 0" );
 535         }
 536
 537         end_time = timeval_sum(&request_time, &timeout);
 538
 539         DEBUG(10,("push_deferred_open_smb_message: pushing message len %u mid %u "
 540                   "timeout time [%u.%06u]\n",
 541                   (unsigned int) smb_len(req->inbuf)+4, (unsigned int)req->mid,
 542                   (unsigned int)end_time.tv_sec,
 543                   (unsigned int)end_time.tv_usec));
 544
 545         return push_queued_message(req, request_time, end_time,
 546                                    private_data, priv_len);
 547 }
 548
 549 struct idle_event {
 550         struct timed_event *te;
 551         struct timeval interval;
 552         char *name;
 553         bool (*handler)(const struct timeval *now, void *private_data);
 554         void *private_data;
 555 };
 556
 557 static void idle_event_handler(struct event_context *ctx,
 558                                struct timed_event *te,
 559                                const struct timeval *now,
 560                                void *private_data)
 561 {
 562         struct idle_event *event =
 563                 talloc_get_type_abort(private_data, struct idle_event);
 564
 565         TALLOC_FREE(event->te);
 566
 567         if (!event->handler(now, event->private_data)) {
 568                 /* Don't repeat, delete ourselves */
 569                 TALLOC_FREE(event);
 570                 return;
 571         }
 572
 573         event->te = event_add_timed(ctx, event,
 574                                     timeval_sum(now, &event->interval),
 575                                     event->name,
 576                                     idle_event_handler, event);
 577
 578         /* We can't do much but fail here. */
 579         SMB_ASSERT(event->te != NULL);
 580 }
 581
 582 struct idle_event *event_add_idle(struct event_context *event_ctx,
 583                                   TALLOC_CTX *mem_ctx,
 584                                   struct timeval interval,
 585                                   const char *name,
 586                                   bool (*handler)(const struct timeval *now,
 587                                                   void *private_data),
 588                                   void *private_data)
 589 {
 590         struct idle_event *result;
 591         struct timeval now = timeval_current();
 592
 593         result = TALLOC_P(mem_ctx, struct idle_event);
 594         if (result == NULL) {
 595                 DEBUG(0, ("talloc failed\n"));
 596                 return NULL;
 597         }
 598
 599         result->interval = interval;
 600         result->handler = handler;
 601         result->private_data = private_data;
 602
 603         if (!(result->name = talloc_asprintf(result, "idle_evt(%s)", name))) {
 604                 DEBUG(0, ("talloc failed\n"));
 605                 TALLOC_FREE(result);
 606                 return NULL;
 607         }
 608
 609         result->te = event_add_timed(event_ctx, result,
 610                                      timeval_sum(&now, &interval),
 611                                      result->name,
 612                                      idle_event_handler, result);
 613         if (result->te == NULL) {
 614                 DEBUG(0, ("event_add_timed failed\n"));
 615                 TALLOC_FREE(result);
 616                 return NULL;
 617         }
 618
 619         return result;
 620 }
 621
 622 /****************************************************************************
 623  Do all async processing in here. This includes kernel oplock messages, change
 624  notify events etc.
 625 ****************************************************************************/
 626
 627 static void async_processing(fd_set *pfds)
 628 {
 629         DEBUG(10,("async_processing: Doing async processing.\n"));
 630
 631         process_aio_queue();
 632
 633         process_kernel_oplocks(smbd_messaging_context(), pfds);
 634
 635         /* Do the aio check again after receive_local_message as it does a
 636            select and may have eaten our signal. */
 637         /* Is this till true? -- vl */
 638         process_aio_queue();
 639
 640         if (got_sig_term) {
 641                 exit_server_cleanly("termination signal");
 642         }
 643
 644         /* check for sighup processing */
 645         if (reload_after_sighup) {
 646                 change_to_root_user();
 647                 DEBUG(1,("Reloading services after SIGHUP\n"));
 648                 reload_services(False);
 649                 reload_after_sighup = 0;
 650         }
 651 }
 652
 653 /****************************************************************************
 654  Add a fd to the set we will be select(2)ing on.
 655 ****************************************************************************/
 656
 657 static int select_on_fd(int fd, int maxfd, fd_set *fds)
 658 {
 659         if (fd != -1) {
 660                 FD_SET(fd, fds);
 661                 maxfd = MAX(maxfd, fd);
 662         }
 663
 664         return maxfd;
 665 }
 666
 667 /****************************************************************************
 668   Do a select on an two fd's - with timeout.
 669
 670   If a local udp message has been pushed onto the
 671   queue (this can only happen during oplock break
 672   processing) call async_processing()
 673
 674   If a pending smb message has been pushed onto the
 675   queue (this can only happen during oplock break
 676   processing) return this next.
 677
 678   If the first smbfd is ready then read an smb from it.
 679   if the second (loopback UDP) fd is ready then read a message
 680   from it and setup the buffer header to identify the length
 681   and from address.
 682   Returns False on timeout or error.
 683   Else returns True.
 684
 685 The timeout is in milliseconds
 686 ****************************************************************************/
 687
 688 static bool receive_message_or_smb(TALLOC_CTX *mem_ctx,
 689                                 char **buffer,
 690                                 size_t *buffer_len,
 691                                 int timeout,
 692                                 size_t *p_unread)
 693 {
 694         fd_set r_fds, w_fds;
 695         int selrtn;
 696         struct timeval to;
 697         int maxfd = 0;
 698         ssize_t len;
 699
 700         *p_unread = 0;
 701         set_smb_read_error(get_srv_read_error(),SMB_READ_OK);
 702
 703  again:
 704
 705         if (timeout >= 0) {
 706                 to.tv_sec = timeout / 1000;
 707                 to.tv_usec = (timeout % 1000) * 1000;
 708         } else {
 709                 to.tv_sec = SMBD_SELECT_TIMEOUT;
 710                 to.tv_usec = 0;
 711         }
 712
 713         /*
 714          * Note that this call must be before processing any SMB
 715          * messages as we need to synchronously process any messages
 716          * we may have sent to ourselves from the previous SMB.
 717          */
 718         message_dispatch(smbd_messaging_context());
 719
 720         /*
 721          * Check to see if we already have a message on the deferred open queue
 722          * and it's time to schedule.
 723          */
 724         if(deferred_open_queue != NULL) {
 725                 bool pop_message = False;
 726                 struct pending_message_list *msg = deferred_open_queue;
 727
 728                 if (timeval_is_zero(&msg->end_time)) {
 729                         pop_message = True;
 730                 } else {
 731                         struct timeval tv;
 732                         SMB_BIG_INT tdif;
 733
 734                         GetTimeOfDay(&tv);
 735                         tdif = usec_time_diff(&msg->end_time, &tv);
 736                         if (tdif <= 0) {
 737                                 /* Timed out. Schedule...*/
 738                                 pop_message = True;
 739                                 DEBUG(10,("receive_message_or_smb: queued message timed out.\n"));
 740                         } else {
 741                                 /* Make a more accurate select timeout. */
 742                                 to.tv_sec = tdif / 1000000;
 743                                 to.tv_usec = tdif % 1000000;
 744                                 DEBUG(10,("receive_message_or_smb: select with timeout of [%u.%06u]\n",
 745                                         (unsigned int)to.tv_sec, (unsigned int)to.tv_usec ));
 746                         }
 747                 }
 748
 749                 if (pop_message) {
 750
 751                         *buffer = (char *)talloc_memdup(mem_ctx, msg->buf.data,
 752                                                         msg->buf.length);
 753                         if (*buffer == NULL) {
 754                                 DEBUG(0, ("talloc failed\n"));
 755                                 set_smb_read_error(get_srv_read_error(),SMB_READ_ERROR);
 756                                 return False;
 757                         }
 758                         *buffer_len = msg->buf.length;
 759
 760                         /* We leave this message on the queue so the open code can
 761                            know this is a retry. */
 762                         DEBUG(5,("receive_message_or_smb: returning deferred open smb message.\n"));
 763                         return True;
 764                 }
 765         }
 766
 767         /*
 768          * Setup the select fd sets.
 769          */
 770
 771         FD_ZERO(&r_fds);
 772         FD_ZERO(&w_fds);
 773
 774         /*
 775          * Ensure we process oplock break messages by preference.
 776          * We have to do this before the select, after the select
 777          * and if the select returns EINTR. This is due to the fact
 778          * that the selects called from async_processing can eat an EINTR
 779          * caused by a signal (we can't take the break message there).
 780          * This is hideously complex - *MUST* be simplified for 3.0 ! JRA.
 781          */
 782
 783         if (oplock_message_waiting(&r_fds)) {
 784                 DEBUG(10,("receive_message_or_smb: oplock_message is waiting.\n"));
 785                 async_processing(&r_fds);
 786                 /*
 787                  * After async processing we must go and do the select again, as
 788                  * the state of the flag in fds for the server file descriptor is
 789                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 790                  */
 791                 goto again;
 792         }
 793
 794         /*
 795          * Are there any timed events waiting ? If so, ensure we don't
 796          * select for longer than it would take to wait for them.
 797          */
 798
 799         {
 800                 struct timeval now;
 801                 GetTimeOfDay(&now);
 802
 803                 event_add_to_select_args(smbd_event_context(), &now,
 804                                          &r_fds, &w_fds, &to, &maxfd);
 805         }
 806
 807         if (timeval_is_zero(&to)) {
 808                 /* Process a timed event now... */
 809                 if (run_events(smbd_event_context(), 0, NULL, NULL)) {
 810                         goto again;
 811                 }
 812         }
 813
 814         {
 815                 int sav;
 816                 START_PROFILE(smbd_idle);
 817
 818                 maxfd = select_on_fd(smbd_server_fd(), maxfd, &r_fds);
 819                 maxfd = select_on_fd(oplock_notify_fd(), maxfd, &r_fds);
 820
 821                 selrtn = sys_select(maxfd+1,&r_fds,&w_fds,NULL,&to);
 822                 sav = errno;
 823
 824                 END_PROFILE(smbd_idle);
 825                 errno = sav;
 826         }
 827
 828         if (run_events(smbd_event_context(), selrtn, &r_fds, &w_fds)) {
 829                 goto again;
 830         }
 831
 832         /* if we get EINTR then maybe we have received an oplock
 833            signal - treat this as select returning 1. This is ugly, but
 834            is the best we can do until the oplock code knows more about
 835            signals */
 836         if (selrtn == -1 && errno == EINTR) {
 837                 async_processing(&r_fds);
 838                 /*
 839                  * After async processing we must go and do the select again, as
 840                  * the state of the flag in fds for the server file descriptor is
 841                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 842                  */
 843                 goto again;
 844         }
 845
 846         /* Check if error */
 847         if (selrtn == -1) {
 848                 /* something is wrong. Maybe the socket is dead? */
 849                 set_smb_read_error(get_srv_read_error(),SMB_READ_ERROR);
 850                 return False;
 851         }
 852
 853         /* Did we timeout ? */
 854         if (selrtn == 0) {
 855                 set_smb_read_error(get_srv_read_error(),SMB_READ_TIMEOUT);
 856                 return False;
 857         }
 858
 859         /*
 860          * Ensure we process oplock break messages by preference.
 861          * This is IMPORTANT ! Otherwise we can starve other processes
 862          * sending us an oplock break message. JRA.
 863          */
 864
 865         if (oplock_message_waiting(&r_fds)) {
 866                 async_processing(&r_fds);
 867                 /*
 868                  * After async processing we must go and do the select again, as
 869                  * the state of the flag in fds for the server file descriptor is
 870                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 871                  */
 872                 goto again;
 873         }
 874
 875         len = receive_smb_talloc(mem_ctx, smbd_server_fd(), buffer, 0, p_unread);
 876
 877         if (len == -1) {
 878                 return False;
 879         }
 880
 881         *buffer_len = (size_t)len;
 882
 883         return True;
 884 }
 885
 886 /*
 887  * Only allow 5 outstanding trans requests. We're allocating memory, so
 888  * prevent a DoS.
 889  */
 890
 891 NTSTATUS allow_new_trans(struct trans_state *list, int mid)
 892 {
 893         int count = 0;
 894         for (; list != NULL; list = list->next) {
 895
 896                 if (list->mid == mid) {
 897                         return NT_STATUS_INVALID_PARAMETER;
 898                 }
 899
 900                 count += 1;
 901         }
 902         if (count > 5) {
 903                 return NT_STATUS_INSUFFICIENT_RESOURCES;
 904         }
 905
 906         return NT_STATUS_OK;
 907 }
 908
 909 /****************************************************************************
 910  We're terminating and have closed all our files/connections etc.
 911  If there are any pending local messages we need to respond to them
 912  before termination so that other smbds don't think we just died whilst
 913  holding oplocks.
 914 ****************************************************************************/
 915
 916 void respond_to_all_remaining_local_messages(void)
 917 {
 918         /*
 919          * Assert we have no exclusive open oplocks.
 920          */
 921
 922         if(get_number_of_exclusive_open_oplocks()) {
 923                 DEBUG(0,("respond_to_all_remaining_local_messages: PANIC : we have %d exclusive oplocks.\n",
 924                         get_number_of_exclusive_open_oplocks() ));
 925                 return;
 926         }
 927
 928         process_kernel_oplocks(smbd_messaging_context(), NULL);
 929
 930         return;
 931 }
 932
 933
 934 /*
 935 These flags determine some of the permissions required to do an operation
 936
 937 Note that I don't set NEED_WRITE on some write operations because they
 938 are used by some brain-dead clients when printing, and I don't want to
 939 force write permissions on print services.
 940 */
 941 #define AS_USER (1<<0)
 942 #define NEED_WRITE (1<<1) /* Must be paired with AS_USER */
 943 #define TIME_INIT (1<<2)
 944 #define CAN_IPC (1<<3) /* Must be paired with AS_USER */
 945 #define AS_GUEST (1<<5) /* Must *NOT* be paired with AS_USER */
 946 #define DO_CHDIR (1<<6)
 947
 948 /*
 949    define a list of possible SMB messages and their corresponding
 950    functions. Any message that has a NULL function is unimplemented -
 951    please feel free to contribute implementations!
 952 */
 953 static const struct smb_message_struct {
 954         const char *name;
 955         void (*fn_new)(connection_struct *conn, struct smb_request *req);
 956         int flags;
 957 } smb_messages[256] = {
 958
 959 /* 0x00 */ { "SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE},
 960 /* 0x01 */ { "SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE},
 961 /* 0x02 */ { "SMBopen",reply_open,AS_USER },
 962 /* 0x03 */ { "SMBcreate",reply_mknew,AS_USER},
 963 /* 0x04 */ { "SMBclose",reply_close,AS_USER | CAN_IPC },
 964 /* 0x05 */ { "SMBflush",reply_flush,AS_USER},
 965 /* 0x06 */ { "SMBunlink",reply_unlink,AS_USER | NEED_WRITE },
 966 /* 0x07 */ { "SMBmv",reply_mv,AS_USER | NEED_WRITE },
 967 /* 0x08 */ { "SMBgetatr",reply_getatr,AS_USER},
 968 /* 0x09 */ { "SMBsetatr",reply_setatr,AS_USER | NEED_WRITE},
 969 /* 0x0a */ { "SMBread",reply_read,AS_USER},
 970 /* 0x0b */ { "SMBwrite",reply_write,AS_USER | CAN_IPC },
 971 /* 0x0c */ { "SMBlock",reply_lock,AS_USER},
 972 /* 0x0d */ { "SMBunlock",reply_unlock,AS_USER},
 973 /* 0x0e */ { "SMBctemp",reply_ctemp,AS_USER },
 974 /* 0x0f */ { "SMBmknew",reply_mknew,AS_USER},
 975 /* 0x10 */ { "SMBcheckpath",reply_checkpath,AS_USER},
 976 /* 0x11 */ { "SMBexit",reply_exit,DO_CHDIR},
 977 /* 0x12 */ { "SMBlseek",reply_lseek,AS_USER},
 978 /* 0x13 */ { "SMBlockread",reply_lockread,AS_USER},
 979 /* 0x14 */ { "SMBwriteunlock",reply_writeunlock,AS_USER},
 980 /* 0x15 */ { NULL, NULL, 0 },
 981 /* 0x16 */ { NULL, NULL, 0 },
 982 /* 0x17 */ { NULL, NULL, 0 },
 983 /* 0x18 */ { NULL, NULL, 0 },
 984 /* 0x19 */ { NULL, NULL, 0 },
 985 /* 0x1a */ { "SMBreadbraw",reply_readbraw,AS_USER},
 986 /* 0x1b */ { "SMBreadBmpx",reply_readbmpx,AS_USER},
 987 /* 0x1c */ { "SMBreadBs",reply_readbs,AS_USER },
 988 /* 0x1d */ { "SMBwritebraw",reply_writebraw,AS_USER},
 989 /* 0x1e */ { "SMBwriteBmpx",reply_writebmpx,AS_USER},
 990 /* 0x1f */ { "SMBwriteBs",reply_writebs,AS_USER},
 991 /* 0x20 */ { "SMBwritec", NULL,0},
 992 /* 0x21 */ { NULL, NULL, 0 },
 993 /* 0x22 */ { "SMBsetattrE",reply_setattrE,AS_USER | NEED_WRITE },
 994 /* 0x23 */ { "SMBgetattrE",reply_getattrE,AS_USER },
 995 /* 0x24 */ { "SMBlockingX",reply_lockingX,AS_USER },
 996 /* 0x25 */ { "SMBtrans",reply_trans,AS_USER | CAN_IPC },
 997 /* 0x26 */ { "SMBtranss",reply_transs,AS_USER | CAN_IPC},
 998 /* 0x27 */ { "SMBioctl",reply_ioctl,0},
 999 /* 0x28 */ { "SMBioctls", NULL,AS_USER},
1000 /* 0x29 */ { "SMBcopy",reply_copy,AS_USER | NEED_WRITE },
1001 /* 0x2a */ { "SMBmove", NULL,AS_USER | NEED_WRITE },
1002 /* 0x2b */ { "SMBecho",reply_echo,0},
1003 /* 0x2c */ { "SMBwriteclose",reply_writeclose,AS_USER},
1004 /* 0x2d */ { "SMBopenX",reply_open_and_X,AS_USER | CAN_IPC },
1005 /* 0x2e */ { "SMBreadX",reply_read_and_X,AS_USER | CAN_IPC },
1006 /* 0x2f */ { "SMBwriteX",reply_write_and_X,AS_USER | CAN_IPC },
1007 /* 0x30 */ { NULL, NULL, 0 },
1008 /* 0x31 */ { NULL, NULL, 0 },
1009 /* 0x32 */ { "SMBtrans2",reply_trans2, AS_USER | CAN_IPC },
1010 /* 0x33 */ { "SMBtranss2",reply_transs2, AS_USER},
1011 /* 0x34 */ { "SMBfindclose",reply_findclose,AS_USER},
1012 /* 0x35 */ { "SMBfindnclose",reply_findnclose,AS_USER},
1013 /* 0x36 */ { NULL, NULL, 0 },
1014 /* 0x37 */ { NULL, NULL, 0 },
1015 /* 0x38 */ { NULL, NULL, 0 },
1016 /* 0x39 */ { NULL, NULL, 0 },
1017 /* 0x3a */ { NULL, NULL, 0 },
1018 /* 0x3b */ { NULL, NULL, 0 },
1019 /* 0x3c */ { NULL, NULL, 0 },
1020 /* 0x3d */ { NULL, NULL, 0 },
1021 /* 0x3e */ { NULL, NULL, 0 },
1022 /* 0x3f */ { NULL, NULL, 0 },
1023 /* 0x40 */ { NULL, NULL, 0 },
1024 /* 0x41 */ { NULL, NULL, 0 },
1025 /* 0x42 */ { NULL, NULL, 0 },
1026 /* 0x43 */ { NULL, NULL, 0 },
1027 /* 0x44 */ { NULL, NULL, 0 },
1028 /* 0x45 */ { NULL, NULL, 0 },
1029 /* 0x46 */ { NULL, NULL, 0 },
1030 /* 0x47 */ { NULL, NULL, 0 },
1031 /* 0x48 */ { NULL, NULL, 0 },
1032 /* 0x49 */ { NULL, NULL, 0 },
1033 /* 0x4a */ { NULL, NULL, 0 },
1034 /* 0x4b */ { NULL, NULL, 0 },
1035 /* 0x4c */ { NULL, NULL, 0 },
1036 /* 0x4d */ { NULL, NULL, 0 },
1037 /* 0x4e */ { NULL, NULL, 0 },
1038 /* 0x4f */ { NULL, NULL, 0 },
1039 /* 0x50 */ { NULL, NULL, 0 },
1040 /* 0x51 */ { NULL, NULL, 0 },
1041 /* 0x52 */ { NULL, NULL, 0 },
1042 /* 0x53 */ { NULL, NULL, 0 },
1043 /* 0x54 */ { NULL, NULL, 0 },
1044 /* 0x55 */ { NULL, NULL, 0 },
1045 /* 0x56 */ { NULL, NULL, 0 },
1046 /* 0x57 */ { NULL, NULL, 0 },
1047 /* 0x58 */ { NULL, NULL, 0 },
1048 /* 0x59 */ { NULL, NULL, 0 },
1049 /* 0x5a */ { NULL, NULL, 0 },
1050 /* 0x5b */ { NULL, NULL, 0 },
1051 /* 0x5c */ { NULL, NULL, 0 },
1052 /* 0x5d */ { NULL, NULL, 0 },
1053 /* 0x5e */ { NULL, NULL, 0 },
1054 /* 0x5f */ { NULL, NULL, 0 },
1055 /* 0x60 */ { NULL, NULL, 0 },
1056 /* 0x61 */ { NULL, NULL, 0 },
1057 /* 0x62 */ { NULL, NULL, 0 },
1058 /* 0x63 */ { NULL, NULL, 0 },
1059 /* 0x64 */ { NULL, NULL, 0 },
1060 /* 0x65 */ { NULL, NULL, 0 },
1061 /* 0x66 */ { NULL, NULL, 0 },
1062 /* 0x67 */ { NULL, NULL, 0 },
1063 /* 0x68 */ { NULL, NULL, 0 },
1064 /* 0x69 */ { NULL, NULL, 0 },
1065 /* 0x6a */ { NULL, NULL, 0 },
1066 /* 0x6b */ { NULL, NULL, 0 },
1067 /* 0x6c */ { NULL, NULL, 0 },
1068 /* 0x6d */ { NULL, NULL, 0 },
1069 /* 0x6e */ { NULL, NULL, 0 },
1070 /* 0x6f */ { NULL, NULL, 0 },
1071 /* 0x70 */ { "SMBtcon",reply_tcon,0},
1072 /* 0x71 */ { "SMBtdis",reply_tdis,DO_CHDIR},
1073 /* 0x72 */ { "SMBnegprot",reply_negprot,0},
1074 /* 0x73 */ { "SMBsesssetupX",reply_sesssetup_and_X,0},
1075 /* 0x74 */ { "SMBulogoffX",reply_ulogoffX, 0}, /* ulogoff doesn't give a valid TID */
1076 /* 0x75 */ { "SMBtconX",reply_tcon_and_X,0},
1077 /* 0x76 */ { NULL, NULL, 0 },
1078 /* 0x77 */ { NULL, NULL, 0 },
1079 /* 0x78 */ { NULL, NULL, 0 },
1080 /* 0x79 */ { NULL, NULL, 0 },
1081 /* 0x7a */ { NULL, NULL, 0 },
1082 /* 0x7b */ { NULL, NULL, 0 },
1083 /* 0x7c */ { NULL, NULL, 0 },
1084 /* 0x7d */ { NULL, NULL, 0 },
1085 /* 0x7e */ { NULL, NULL, 0 },
1086 /* 0x7f */ { NULL, NULL, 0 },
1087 /* 0x80 */ { "SMBdskattr",reply_dskattr,AS_USER},
1088 /* 0x81 */ { "SMBsearch",reply_search,AS_USER},
1089 /* 0x82 */ { "SMBffirst",reply_search,AS_USER},
1090 /* 0x83 */ { "SMBfunique",reply_search,AS_USER},
1091 /* 0x84 */ { "SMBfclose",reply_fclose,AS_USER},
1092 /* 0x85 */ { NULL, NULL, 0 },
1093 /* 0x86 */ { NULL, NULL, 0 },
1094 /* 0x87 */ { NULL, NULL, 0 },
1095 /* 0x88 */ { NULL, NULL, 0 },
1096 /* 0x89 */ { NULL, NULL, 0 },
1097 /* 0x8a */ { NULL, NULL, 0 },
1098 /* 0x8b */ { NULL, NULL, 0 },
1099 /* 0x8c */ { NULL, NULL, 0 },
1100 /* 0x8d */ { NULL, NULL, 0 },
1101 /* 0x8e */ { NULL, NULL, 0 },
1102 /* 0x8f */ { NULL, NULL, 0 },
1103 /* 0x90 */ { NULL, NULL, 0 },
1104 /* 0x91 */ { NULL, NULL, 0 },
1105 /* 0x92 */ { NULL, NULL, 0 },
1106 /* 0x93 */ { NULL, NULL, 0 },
1107 /* 0x94 */ { NULL, NULL, 0 },
1108 /* 0x95 */ { NULL, NULL, 0 },
1109 /* 0x96 */ { NULL, NULL, 0 },
1110 /* 0x97 */ { NULL, NULL, 0 },
1111 /* 0x98 */ { NULL, NULL, 0 },
1112 /* 0x99 */ { NULL, NULL, 0 },
1113 /* 0x9a */ { NULL, NULL, 0 },
1114 /* 0x9b */ { NULL, NULL, 0 },
1115 /* 0x9c */ { NULL, NULL, 0 },
1116 /* 0x9d */ { NULL, NULL, 0 },
1117 /* 0x9e */ { NULL, NULL, 0 },
1118 /* 0x9f */ { NULL, NULL, 0 },
1119 /* 0xa0 */ { "SMBnttrans",reply_nttrans, AS_USER | CAN_IPC },
1120 /* 0xa1 */ { "SMBnttranss",reply_nttranss, AS_USER | CAN_IPC },
1121 /* 0xa2 */ { "SMBntcreateX",reply_ntcreate_and_X, AS_USER | CAN_IPC },
1122 /* 0xa3 */ { NULL, NULL, 0 },
1123 /* 0xa4 */ { "SMBntcancel",reply_ntcancel, 0 },
1124 /* 0xa5 */ { "SMBntrename",reply_ntrename, AS_USER | NEED_WRITE },
1125 /* 0xa6 */ { NULL, NULL, 0 },
1126 /* 0xa7 */ { NULL, NULL, 0 },
1127 /* 0xa8 */ { NULL, NULL, 0 },
1128 /* 0xa9 */ { NULL, NULL, 0 },
1129 /* 0xaa */ { NULL, NULL, 0 },
1130 /* 0xab */ { NULL, NULL, 0 },
1131 /* 0xac */ { NULL, NULL, 0 },
1132 /* 0xad */ { NULL, NULL, 0 },
1133 /* 0xae */ { NULL, NULL, 0 },
1134 /* 0xaf */ { NULL, NULL, 0 },
1135 /* 0xb0 */ { NULL, NULL, 0 },
1136 /* 0xb1 */ { NULL, NULL, 0 },
1137 /* 0xb2 */ { NULL, NULL, 0 },
1138 /* 0xb3 */ { NULL, NULL, 0 },
1139 /* 0xb4 */ { NULL, NULL, 0 },
1140 /* 0xb5 */ { NULL, NULL, 0 },
1141 /* 0xb6 */ { NULL, NULL, 0 },
1142 /* 0xb7 */ { NULL, NULL, 0 },
1143 /* 0xb8 */ { NULL, NULL, 0 },
1144 /* 0xb9 */ { NULL, NULL, 0 },
1145 /* 0xba */ { NULL, NULL, 0 },
1146 /* 0xbb */ { NULL, NULL, 0 },
1147 /* 0xbc */ { NULL, NULL, 0 },
1148 /* 0xbd */ { NULL, NULL, 0 },
1149 /* 0xbe */ { NULL, NULL, 0 },
1150 /* 0xbf */ { NULL, NULL, 0 },
1151 /* 0xc0 */ { "SMBsplopen",reply_printopen,AS_USER},
1152 /* 0xc1 */ { "SMBsplwr",reply_printwrite,AS_USER},
1153 /* 0xc2 */ { "SMBsplclose",reply_printclose,AS_USER},
1154 /* 0xc3 */ { "SMBsplretq",reply_printqueue,AS_USER},
1155 /* 0xc4 */ { NULL, NULL, 0 },
1156 /* 0xc5 */ { NULL, NULL, 0 },
1157 /* 0xc6 */ { NULL, NULL, 0 },
1158 /* 0xc7 */ { NULL, NULL, 0 },
1159 /* 0xc8 */ { NULL, NULL, 0 },
1160 /* 0xc9 */ { NULL, NULL, 0 },
1161 /* 0xca */ { NULL, NULL, 0 },
1162 /* 0xcb */ { NULL, NULL, 0 },
1163 /* 0xcc */ { NULL, NULL, 0 },
1164 /* 0xcd */ { NULL, NULL, 0 },
1165 /* 0xce */ { NULL, NULL, 0 },
1166 /* 0xcf */ { NULL, NULL, 0 },
1167 /* 0xd0 */ { "SMBsends",reply_sends,AS_GUEST},
1168 /* 0xd1 */ { "SMBsendb", NULL,AS_GUEST},
1169 /* 0xd2 */ { "SMBfwdname", NULL,AS_GUEST},
1170 /* 0xd3 */ { "SMBcancelf", NULL,AS_GUEST},
1171 /* 0xd4 */ { "SMBgetmac", NULL,AS_GUEST},
1172 /* 0xd5 */ { "SMBsendstrt",reply_sendstrt,AS_GUEST},
1173 /* 0xd6 */ { "SMBsendend",reply_sendend,AS_GUEST},
1174 /* 0xd7 */ { "SMBsendtxt",reply_sendtxt,AS_GUEST},
1175 /* 0xd8 */ { NULL, NULL, 0 },
1176 /* 0xd9 */ { NULL, NULL, 0 },
1177 /* 0xda */ { NULL, NULL, 0 },
1178 /* 0xdb */ { NULL, NULL, 0 },
1179 /* 0xdc */ { NULL, NULL, 0 },
1180 /* 0xdd */ { NULL, NULL, 0 },
1181 /* 0xde */ { NULL, NULL, 0 },
1182 /* 0xdf */ { NULL, NULL, 0 },
1183 /* 0xe0 */ { NULL, NULL, 0 },
1184 /* 0xe1 */ { NULL, NULL, 0 },
1185 /* 0xe2 */ { NULL, NULL, 0 },
1186 /* 0xe3 */ { NULL, NULL, 0 },
1187 /* 0xe4 */ { NULL, NULL, 0 },
1188 /* 0xe5 */ { NULL, NULL, 0 },
1189 /* 0xe6 */ { NULL, NULL, 0 },
1190 /* 0xe7 */ { NULL, NULL, 0 },
1191 /* 0xe8 */ { NULL, NULL, 0 },
1192 /* 0xe9 */ { NULL, NULL, 0 },
1193 /* 0xea */ { NULL, NULL, 0 },
1194 /* 0xeb */ { NULL, NULL, 0 },
1195 /* 0xec */ { NULL, NULL, 0 },
1196 /* 0xed */ { NULL, NULL, 0 },
1197 /* 0xee */ { NULL, NULL, 0 },
1198 /* 0xef */ { NULL, NULL, 0 },
1199 /* 0xf0 */ { NULL, NULL, 0 },
1200 /* 0xf1 */ { NULL, NULL, 0 },
1201 /* 0xf2 */ { NULL, NULL, 0 },
1202 /* 0xf3 */ { NULL, NULL, 0 },
1203 /* 0xf4 */ { NULL, NULL, 0 },
1204 /* 0xf5 */ { NULL, NULL, 0 },
1205 /* 0xf6 */ { NULL, NULL, 0 },
1206 /* 0xf7 */ { NULL, NULL, 0 },
1207 /* 0xf8 */ { NULL, NULL, 0 },
1208 /* 0xf9 */ { NULL, NULL, 0 },
1209 /* 0xfa */ { NULL, NULL, 0 },
1210 /* 0xfb */ { NULL, NULL, 0 },
1211 /* 0xfc */ { NULL, NULL, 0 },
1212 /* 0xfd */ { NULL, NULL, 0 },
1213 /* 0xfe */ { NULL, NULL, 0 },
1214 /* 0xff */ { NULL, NULL, 0 }
1215
1216 };
1217
1218 /*******************************************************************
1219  allocate and initialize a reply packet
1220 ********************************************************************/
1221
1222 void reply_outbuf(struct smb_request *req, uint8 num_words, uint32 num_bytes)
1223 {
1224         /*
1225          * Protect against integer wrap
1226          */
1227         if ((num_bytes > 0xffffff)
1228             || ((num_bytes + smb_size + num_words*2) > 0xffffff)) {
1229                 char *msg;
1230                 asprintf(&msg, "num_bytes too large: %u",
1231                          (unsigned)num_bytes);
1232                 smb_panic(msg);
1233         }
1234
1235         if (!(req->outbuf = TALLOC_ARRAY(
1236                       req, uint8,
1237                       smb_size + num_words*2 + num_bytes))) {
1238                 smb_panic("could not allocate output buffer\n");
1239         }
1240
1241         construct_reply_common((char *)req->inbuf, (char *)req->outbuf);
1242         set_message((char *)req->outbuf, num_words, num_bytes, False);
1243         /*
1244          * Zero out the word area, the caller has to take care of the bcc area
1245          * himself
1246          */
1247         if (num_words != 0) {
1248                 memset(req->outbuf + smb_vwv0, 0, num_words*2);
1249         }
1250
1251         return;
1252 }
1253
1254
1255 /*******************************************************************
1256  Dump a packet to a file.
1257 ********************************************************************/
1258
1259 static void smb_dump(const char *name, int type, const char *data, ssize_t len)
1260 {
1261         int fd, i;
1262         char *fname = NULL;
1263         if (DEBUGLEVEL < 50) {
1264                 return;
1265         }
1266
1267         if (len < 4) len = smb_len(data)+4;
1268         for (i=1;i<100;i++) {
1269                 asprintf(&fname, "/tmp/%s.%d.%s", name, i,
1270                                 type ? "req" : "resp");
1271                 if (!fname) {
1272                         return;
1273                 }
1274                 fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0644);
1275                 if (fd != -1 || errno != EEXIST) break;
1276         }
1277         if (fd != -1) {
1278                 ssize_t ret = write(fd, data, len);
1279                 if (ret != len)
1280                         DEBUG(0,("smb_dump: problem: write returned %d\n", (int)ret ));
1281                 close(fd);
1282                 DEBUG(0,("created %s len %lu\n", fname, (unsigned long)len));
1283         }
1284         SAFE_FREE(fname);
1285 }
1286
1287 /****************************************************************************
1288  Prepare everything for calling the actual request function, and potentially
1289  call the request function via the "new" interface.
1290
1291  Return False if the "legacy" function needs to be called, everything is
1292  prepared.
1293
1294  Return True if we're done.
1295
1296  I know this API sucks, but it is the one with the least code change I could
1297  find.
1298 ****************************************************************************/
1299
1300 static void switch_message(uint8 type, struct smb_request *req, int size)
1301 {
1302         int flags;
1303         uint16 session_tag;
1304         connection_struct *conn;
1305
1306         static uint16 last_session_tag = UID_FIELD_INVALID;
1307
1308         errno = 0;
1309
1310         /* Make sure this is an SMB packet. smb_size contains NetBIOS header
1311          * so subtract 4 from it. */
1312         if ((strncmp(smb_base(req->inbuf),"\377SMB",4) != 0)
1313             || (size < (smb_size - 4))) {
1314                 DEBUG(2,("Non-SMB packet of length %d. Terminating server\n",
1315                          smb_len(req->inbuf)));
1316                 exit_server_cleanly("Non-SMB packet");
1317         }
1318
1319         if (smb_messages[type].fn_new == NULL) {
1320                 DEBUG(0,("Unknown message type %d!\n",type));
1321                 smb_dump("Unknown", 1, (char *)req->inbuf, size);
1322                 reply_unknown_new(req, type);
1323                 return;
1324         }
1325
1326         flags = smb_messages[type].flags;
1327
1328         /* In share mode security we must ignore the vuid. */
1329         session_tag = (lp_security() == SEC_SHARE)
1330                 ? UID_FIELD_INVALID : req->vuid;
1331         conn = conn_find(req->tid);
1332
1333         DEBUG(3,("switch message %s (pid %d) conn 0x%lx\n", smb_fn_name(type),
1334                  (int)sys_getpid(), (unsigned long)conn));
1335
1336         smb_dump(smb_fn_name(type), 1, (char *)req->inbuf, size);
1337
1338         /* Ensure this value is replaced in the incoming packet. */
1339         SSVAL(req->inbuf,smb_uid,session_tag);
1340
1341         /*
1342          * Ensure the correct username is in current_user_info.  This is a
1343          * really ugly bugfix for problems with multiple session_setup_and_X's
1344          * being done and allowing %U and %G substitutions to work correctly.
1345          * There is a reason this code is done here, don't move it unless you
1346          * know what you're doing... :-).
1347          * JRA.
1348          */
1349
1350         if (session_tag != last_session_tag) {
1351                 user_struct *vuser = NULL;
1352
1353                 last_session_tag = session_tag;
1354                 if(session_tag != UID_FIELD_INVALID) {
1355                         vuser = get_valid_user_struct(session_tag);
1356                         if (vuser) {
1357                                 set_current_user_info(&vuser->user);
1358                         }
1359                 }
1360         }
1361
1362         /* Does this call need to be run as the connected user? */
1363         if (flags & AS_USER) {
1364
1365                 /* Does this call need a valid tree connection? */
1366                 if (!conn) {
1367                         /*
1368                          * Amazingly, the error code depends on the command
1369                          * (from Samba4).
1370                          */
1371                         if (type == SMBntcreateX) {
1372                                 reply_nterror(req, NT_STATUS_INVALID_HANDLE);
1373                         } else {
1374                                 reply_doserror(req, ERRSRV, ERRinvnid);
1375                         }
1376                         return;
1377                 }
1378
1379                 if (!change_to_user(conn,session_tag)) {
1380                         reply_nterror(req, NT_STATUS_DOS(ERRSRV, ERRbaduid));
1381                         return;
1382                 }
1383
1384                 /* All NEED_WRITE and CAN_IPC flags must also have AS_USER. */
1385
1386                 /* Does it need write permission? */
1387                 if ((flags & NEED_WRITE) && !CAN_WRITE(conn)) {
1388                         reply_nterror(req, NT_STATUS_MEDIA_WRITE_PROTECTED);
1389                         return;
1390                 }
1391
1392                 /* IPC services are limited */
1393                 if (IS_IPC(conn) && !(flags & CAN_IPC)) {
1394                         reply_doserror(req, ERRSRV,ERRaccess);
1395                         return;
1396                 }
1397         } else {
1398                 /* This call needs to be run as root */
1399                 change_to_root_user();
1400         }
1401
1402         /* load service specific parameters */
1403         if (conn) {
1404                 if (!set_current_service(conn,SVAL(req->inbuf,smb_flg),
1405                                          (flags & (AS_USER|DO_CHDIR)
1406                                           ?True:False))) {
1407                         reply_doserror(req, ERRSRV, ERRaccess);
1408                         return;
1409                 }
1410                 conn->num_smb_operations++;
1411         }
1412
1413         /* does this protocol need to be run as guest? */
1414         if ((flags & AS_GUEST)
1415             && (!change_to_guest() ||
1416                 !check_access(smbd_server_fd(), lp_hostsallow(-1),
1417                               lp_hostsdeny(-1)))) {
1418                 reply_doserror(req, ERRSRV, ERRaccess);
1419                 return;
1420         }
1421
1422         smb_messages[type].fn_new(conn, req);
1423 }
1424
1425 /****************************************************************************
1426  Construct a reply to the incoming packet.
1427 ****************************************************************************/
1428
1429 static void construct_reply(char *inbuf, int size, size_t unread_bytes)
1430 {
1431         uint8 type = CVAL(inbuf,smb_com);
1432         struct smb_request *req;
1433
1434         chain_size = 0;
1435         file_chain_reset();
1436         reset_chain_p();
1437
1438         if (!(req = talloc(talloc_tos(), struct smb_request))) {
1439                 smb_panic("could not allocate smb_request");
1440         }
1441         init_smb_request(req, (uint8 *)inbuf, unread_bytes);
1442
1443         switch_message(type, req, size);
1444
1445         if (req->unread_bytes) {
1446                 /* writeX failed. drain socket. */
1447                 if (drain_socket(smbd_server_fd(), req->unread_bytes) !=
1448                                 req->unread_bytes) {
1449                         smb_panic("failed to drain pending bytes");
1450                 }
1451                 req->unread_bytes = 0;
1452         }
1453
1454         if (req->outbuf == NULL) {
1455                 return;
1456         }
1457
1458         if (CVAL(req->outbuf,0) == 0) {
1459                 show_msg((char *)req->outbuf);
1460         }
1461
1462         if (!send_smb(smbd_server_fd(), (char *)req->outbuf)) {
1463                 exit_server_cleanly("construct_reply: send_smb failed.");
1464         }
1465
1466         TALLOC_FREE(req);
1467
1468         return;
1469 }
1470
1471 /****************************************************************************
1472  Process an smb from the client
1473 ****************************************************************************/
1474
1475 static void process_smb(char *inbuf, size_t nread, size_t unread_bytes)
1476 {
1477         static int trans_num;
1478         int msg_type = CVAL(inbuf,0);
1479
1480         DO_PROFILE_INC(smb_count);
1481
1482         if (trans_num == 0) {
1483                 char addr[INET6_ADDRSTRLEN];
1484
1485                 /* on the first packet, check the global hosts allow/ hosts
1486                 deny parameters before doing any parsing of the packet
1487                 passed to us by the client.  This prevents attacks on our
1488                 parsing code from hosts not in the hosts allow list */
1489
1490                 if (!check_access(smbd_server_fd(), lp_hostsallow(-1),
1491                                   lp_hostsdeny(-1))) {
1492                         /* send a negative session response "not listening on calling name" */
1493                         static unsigned char buf[5] = {0x83, 0, 0, 1, 0x81};
1494                         DEBUG( 1, ( "Connection denied from %s\n",
1495                                 client_addr(get_client_fd(),addr,sizeof(addr)) ) );
1496                         (void)send_smb(smbd_server_fd(),(char *)buf);
1497                         exit_server_cleanly("connection denied");
1498                 }
1499         }
1500
1501         DEBUG( 6, ( "got message type 0x%x of len 0x%x\n", msg_type,
1502                     smb_len(inbuf) ) );
1503         DEBUG( 3, ( "Transaction %d of length %d (%u toread)\n", trans_num,
1504                                 (int)nread,
1505                                 (unsigned int)unread_bytes ));
1506
1507         if (msg_type != 0) {
1508                 /*
1509                  * NetBIOS session request, keepalive, etc.
1510                  */
1511                 reply_special(inbuf);
1512                 return;
1513         }
1514
1515         show_msg(inbuf);
1516
1517         construct_reply(inbuf,nread,unread_bytes);
1518
1519         trans_num++;
1520 }
1521
1522 /****************************************************************************
1523  Return a string containing the function name of a SMB command.
1524 ****************************************************************************/
1525
1526 const char *smb_fn_name(int type)
1527 {
1528         const char *unknown_name = "SMBunknown";
1529
1530         if (smb_messages[type].name == NULL)
1531                 return(unknown_name);
1532
1533         return(smb_messages[type].name);
1534 }
1535
1536 /****************************************************************************
1537  Helper functions for contruct_reply.
1538 ****************************************************************************/
1539
1540 static uint32 common_flags2 = FLAGS2_LONG_PATH_COMPONENTS|FLAGS2_32_BIT_ERROR_CODES;
1541
1542 void add_to_common_flags2(uint32 v)
1543 {
1544         common_flags2 |= v;
1545 }
1546
1547 void remove_from_common_flags2(uint32 v)
1548 {
1549         common_flags2 &= ~v;
1550 }
1551
1552 void construct_reply_common(const char *inbuf, char *outbuf)
1553 {
1554         set_message(outbuf,0,0,False);
1555
1556         SCVAL(outbuf,smb_com,CVAL(inbuf,smb_com));
1557         SIVAL(outbuf,smb_rcls,0);
1558         SCVAL(outbuf,smb_flg, FLAG_REPLY | (CVAL(inbuf,smb_flg) & FLAG_CASELESS_PATHNAMES));
1559         SSVAL(outbuf,smb_flg2,
1560                 (SVAL(inbuf,smb_flg2) & FLAGS2_UNICODE_STRINGS) |
1561                 common_flags2);
1562         memset(outbuf+smb_pidhigh,'\0',(smb_tid-smb_pidhigh));
1563
1564         SSVAL(outbuf,smb_tid,SVAL(inbuf,smb_tid));
1565         SSVAL(outbuf,smb_pid,SVAL(inbuf,smb_pid));
1566         SSVAL(outbuf,smb_uid,SVAL(inbuf,smb_uid));
1567         SSVAL(outbuf,smb_mid,SVAL(inbuf,smb_mid));
1568 }
1569
1570 /****************************************************************************
1571  Construct a chained reply and add it to the already made reply
1572 ****************************************************************************/
1573
1574 void chain_reply(struct smb_request *req)
1575 {
1576         static char *orig_inbuf;
1577
1578         /*
1579          * Dirty little const_discard: We mess with req->inbuf, which is
1580          * declared as const. If maybe at some point this routine gets
1581          * rewritten, this const_discard could go away.
1582          */
1583         char *inbuf = CONST_DISCARD(char *, req->inbuf);
1584         int size = smb_len(req->inbuf)+4;
1585
1586         int smb_com1, smb_com2 = CVAL(inbuf,smb_vwv0);
1587         unsigned smb_off2 = SVAL(inbuf,smb_vwv1);
1588         char *inbuf2;
1589         int outsize2;
1590         int new_size;
1591         char inbuf_saved[smb_wct];
1592         char *outbuf = (char *)req->outbuf;
1593         size_t outsize = smb_len(outbuf) + 4;
1594         size_t outsize_padded;
1595         size_t ofs, to_move;
1596
1597         struct smb_request *req2;
1598         size_t caller_outputlen;
1599         char *caller_output;
1600
1601         /* Maybe its not chained, or it's an error packet. */
1602         if (smb_com2 == 0xFF || SVAL(outbuf,smb_rcls) != 0) {
1603                 SCVAL(outbuf,smb_vwv0,0xFF);
1604                 return;
1605         }
1606
1607         if (chain_size == 0) {
1608                 /* this is the first part of the chain */
1609                 orig_inbuf = inbuf;
1610         }
1611
1612         /*
1613          * We need to save the output the caller added to the chain so that we
1614          * can splice it into the final output buffer later.
1615          */
1616
1617         caller_outputlen = outsize - smb_wct;
1618
1619         caller_output = (char *)memdup(outbuf + smb_wct, caller_outputlen);
1620
1621         if (caller_output == NULL) {
1622                 /* TODO: NT_STATUS_NO_MEMORY */
1623                 smb_panic("could not dup outbuf");
1624         }
1625
1626         /*
1627          * The original Win95 redirector dies on a reply to
1628          * a lockingX and read chain unless the chain reply is
1629          * 4 byte aligned. JRA.
1630          */
1631
1632         outsize_padded = (outsize + 3) & ~3;
1633
1634         /*
1635          * remember how much the caller added to the chain, only counting
1636          * stuff after the parameter words
1637          */
1638         chain_size += outsize_padded - smb_wct;
1639
1640         /*
1641          * work out pointers into the original packets. The
1642          * headers on these need to be filled in
1643          */
1644         inbuf2 = orig_inbuf + smb_off2 + 4 - smb_wct;
1645
1646         /* remember the original command type */
1647         smb_com1 = CVAL(orig_inbuf,smb_com);
1648
1649         /* save the data which will be overwritten by the new headers */
1650         memcpy(inbuf_saved,inbuf2,smb_wct);
1651
1652         /* give the new packet the same header as the last part of the SMB */
1653         memmove(inbuf2,inbuf,smb_wct);
1654
1655         /* create the in buffer */
1656         SCVAL(inbuf2,smb_com,smb_com2);
1657
1658         /* work out the new size for the in buffer. */
1659         new_size = size - (inbuf2 - inbuf);
1660         if (new_size < 0) {
1661                 DEBUG(0,("chain_reply: chain packet size incorrect "
1662                          "(orig size = %d, offset = %d)\n",
1663                          size, (int)(inbuf2 - inbuf) ));
1664                 exit_server_cleanly("Bad chained packet");
1665                 return;
1666         }
1667
1668         /* And set it in the header. */
1669         smb_setlen(inbuf2, new_size - 4);
1670
1671         DEBUG(3,("Chained message\n"));
1672         show_msg(inbuf2);
1673
1674         if (!(req2 = talloc(talloc_tos(), struct smb_request))) {
1675                 smb_panic("could not allocate smb_request");
1676         }
1677         init_smb_request(req2, (uint8 *)inbuf2,0);
1678
1679         /* process the request */
1680         switch_message(smb_com2, req2, new_size);
1681
1682         /*
1683          * We don't accept deferred operations in chained requests.
1684          */
1685         SMB_ASSERT(req2->outbuf != NULL);
1686         outsize2 = smb_len(req2->outbuf)+4;
1687
1688         /*
1689          * Move away the new command output so that caller_output fits in,
1690          * copy in the caller_output saved above.
1691          */
1692
1693         SMB_ASSERT(outsize_padded >= smb_wct);
1694
1695         /*
1696          * "ofs" is the space we need for caller_output. Equal to
1697          * caller_outputlen plus the padding.
1698          */
1699
1700         ofs = outsize_padded - smb_wct;
1701
1702         /*
1703          * "to_move" is the amount of bytes the secondary routine gave us
1704          */
1705
1706         to_move = outsize2 - smb_wct;
1707
1708         if (to_move + ofs + smb_wct + chain_size > max_send) {
1709                 smb_panic("replies too large -- would have to cut");
1710         }
1711
1712         /*
1713          * In the "new" API "outbuf" is allocated via reply_outbuf, just for
1714          * the first request in the chain. So we have to re-allocate it. In
1715          * the "old" API the only outbuf ever used is the global OutBuffer
1716          * which is always large enough.
1717          */
1718
1719         outbuf = TALLOC_REALLOC_ARRAY(NULL, outbuf, char,
1720                                       to_move + ofs + smb_wct);
1721         if (outbuf == NULL) {
1722                 smb_panic("could not realloc outbuf");
1723         }
1724
1725         req->outbuf = (uint8 *)outbuf;
1726
1727         memmove(outbuf + smb_wct + ofs, req2->outbuf + smb_wct, to_move);
1728         memcpy(outbuf + smb_wct, caller_output, caller_outputlen);
1729
1730         /*
1731          * copy the new reply header over the old one but preserve the smb_com
1732          * field
1733          */
1734         memmove(outbuf, req2->outbuf, smb_wct);
1735         SCVAL(outbuf, smb_com, smb_com1);
1736
1737         /*
1738          * We've just copied in the whole "wct" area from the secondary
1739          * function. Fix up the chaining: com2 and the offset need to be
1740          * readjusted.
1741          */
1742
1743         SCVAL(outbuf, smb_vwv0, smb_com2);
1744         SSVAL(outbuf, smb_vwv1, chain_size + smb_wct - 4);
1745
1746         if (outsize_padded > outsize) {
1747
1748                 /*
1749                  * Due to padding we have some uninitialized bytes after the
1750                  * caller's output
1751                  */
1752
1753                 memset(outbuf + outsize, 0, outsize_padded - outsize);
1754         }
1755
1756         smb_setlen(outbuf, outsize2 + chain_size - 4);
1757
1758         /*
1759          * restore the saved data, being careful not to overwrite any data
1760          * from the reply header
1761          */
1762         memcpy(inbuf2,inbuf_saved,smb_wct);
1763
1764         SAFE_FREE(caller_output);
1765         TALLOC_FREE(req2);
1766
1767         return;
1768 }
1769
1770 /****************************************************************************
1771  Setup the needed select timeout in milliseconds.
1772 ****************************************************************************/
1773
1774 static int setup_select_timeout(void)
1775 {
1776         int select_timeout;
1777
1778         select_timeout = SMBD_SELECT_TIMEOUT*1000;
1779
1780         if (print_notify_messages_pending()) {
1781                 select_timeout = MIN(select_timeout, 1000);
1782         }
1783
1784         return select_timeout;
1785 }
1786
1787 /****************************************************************************
1788  Check if services need reloading.
1789 ****************************************************************************/
1790
1791 void check_reload(time_t t)
1792 {
1793         static pid_t mypid = 0;
1794         static time_t last_smb_conf_reload_time = 0;
1795         static time_t last_printer_reload_time = 0;
1796         time_t printcap_cache_time = (time_t)lp_printcap_cache_time();
1797
1798         if(last_smb_conf_reload_time == 0) {
1799                 last_smb_conf_reload_time = t;
1800                 /* Our printing subsystem might not be ready at smbd start up.
1801                    Then no printer is available till the first printers check
1802                    is performed.  A lower initial interval circumvents this. */
1803                 if ( printcap_cache_time > 60 )
1804                         last_printer_reload_time = t - printcap_cache_time + 60;
1805                 else
1806                         last_printer_reload_time = t;
1807         }
1808
1809         if (mypid != getpid()) { /* First time or fork happened meanwhile */
1810                 /* randomize over 60 second the printcap reload to avoid all
1811                  * process hitting cupsd at the same time */
1812                 int time_range = 60;
1813
1814                 last_printer_reload_time += random() % time_range;
1815                 mypid = getpid();
1816         }
1817
1818         if (reload_after_sighup || (t >= last_smb_conf_reload_time+SMBD_RELOAD_CHECK)) {
1819                 reload_services(True);
1820                 reload_after_sighup = False;
1821                 last_smb_conf_reload_time = t;
1822         }
1823
1824         /* 'printcap cache time = 0' disable the feature */
1825
1826         if ( printcap_cache_time != 0 )
1827         {
1828                 /* see if it's time to reload or if the clock has been set back */
1829
1830                 if ( (t >= last_printer_reload_time+printcap_cache_time)
1831                         || (t-last_printer_reload_time  < 0) )
1832                 {
1833                         DEBUG( 3,( "Printcap cache time expired.\n"));
1834                         reload_printers();
1835                         last_printer_reload_time = t;
1836                 }
1837         }
1838 }
1839
1840 /****************************************************************************
1841  Process any timeout housekeeping. Return False if the caller should exit.
1842 ****************************************************************************/
1843
1844 static bool timeout_processing(int *select_timeout,
1845                                time_t *last_timeout_processing_time)
1846 {
1847         time_t t;
1848
1849         if (*get_srv_read_error() == SMB_READ_EOF) {
1850                 DEBUG(3,("timeout_processing: End of file from client (client has disconnected).\n"));
1851                 return false;
1852         }
1853
1854         if (*get_srv_read_error() == SMB_READ_ERROR) {
1855                 DEBUG(3,("timeout_processing: receive_smb error (%s) Exiting\n",
1856                         strerror(errno)));
1857                 return false;
1858         }
1859
1860         if (*get_srv_read_error() == SMB_READ_BAD_SIG) {
1861                 DEBUG(3,("timeout_processing: receive_smb error bad smb signature. Exiting\n"));
1862                 return false;
1863         }
1864
1865         *last_timeout_processing_time = t = time(NULL);
1866
1867         /* become root again if waiting */
1868         change_to_root_user();
1869
1870         /* check if we need to reload services */
1871         check_reload(t);
1872
1873         if(global_machine_password_needs_changing &&
1874                         /* for ADS we need to do a regular ADS password change, not a domain
1875                                         password change */
1876                         lp_security() == SEC_DOMAIN) {
1877
1878                 unsigned char trust_passwd_hash[16];
1879                 time_t lct;
1880
1881                 /*
1882                  * We're in domain level security, and the code that
1883                  * read the machine password flagged that the machine
1884                  * password needs changing.
1885                  */
1886
1887                 /*
1888                  * First, open the machine password file with an exclusive lock.
1889                  */
1890
1891                 if (secrets_lock_trust_account_password(lp_workgroup(), True) == False) {
1892                         DEBUG(0,("process: unable to lock the machine account password for \
1893 machine %s in domain %s.\n", global_myname(), lp_workgroup() ));
1894                         return True;
1895                 }
1896
1897                 if(!secrets_fetch_trust_account_password(lp_workgroup(), trust_passwd_hash, &lct, NULL)) {
1898                         DEBUG(0,("process: unable to read the machine account password for \
1899 machine %s in domain %s.\n", global_myname(), lp_workgroup()));
1900                         secrets_lock_trust_account_password(lp_workgroup(), False);
1901                         return True;
1902                 }
1903
1904                 /*
1905                  * Make sure someone else hasn't already done this.
1906                  */
1907
1908                 if(t < lct + lp_machine_password_timeout()) {
1909                         global_machine_password_needs_changing = False;
1910                         secrets_lock_trust_account_password(lp_workgroup(), False);
1911                         return True;
1912                 }
1913
1914                 /* always just contact the PDC here */
1915
1916                 change_trust_account_password( lp_workgroup(), NULL);
1917                 global_machine_password_needs_changing = False;
1918                 secrets_lock_trust_account_password(lp_workgroup(), False);
1919         }
1920
1921         /* update printer queue caches if necessary */
1922
1923         update_monitored_printq_cache();
1924
1925         /*
1926          * Now we are root, check if the log files need pruning.
1927          * Force a log file check.
1928          */
1929         force_check_log_size();
1930         check_log_size();
1931
1932         /* Send any queued printer notify message to interested smbd's. */
1933
1934         print_notify_send_messages(smbd_messaging_context(), 0);
1935
1936         /*
1937          * Modify the select timeout depending upon
1938          * what we have remaining in our queues.
1939          */
1940
1941         *select_timeout = setup_select_timeout();
1942
1943         return True;
1944 }
1945
1946 /****************************************************************************
1947  Process commands from the client
1948 ****************************************************************************/
1949
1950 void smbd_process(void)
1951 {
1952         time_t last_timeout_processing_time = time(NULL);
1953         unsigned int num_smbs = 0;
1954         size_t unread_bytes = 0;
1955
1956         max_recv = MIN(lp_maxxmit(),BUFFER_SIZE);
1957
1958         while (True) {
1959                 int select_timeout = setup_select_timeout();
1960                 int num_echos;
1961                 char *inbuf;
1962                 size_t inbuf_len;
1963                 TALLOC_CTX *frame = talloc_stackframe();
1964
1965                 errno = 0;
1966
1967                 /* Did someone ask for immediate checks on things like blocking locks ? */
1968                 if (select_timeout == 0) {
1969                         if(!timeout_processing(&select_timeout,
1970                                                &last_timeout_processing_time))
1971                                 return;
1972                         num_smbs = 0; /* Reset smb counter. */
1973                 }
1974
1975                 run_events(smbd_event_context(), 0, NULL, NULL);
1976
1977                 while (!receive_message_or_smb(NULL, &inbuf, &inbuf_len,
1978                                                select_timeout, &unread_bytes)) {
1979                         if(!timeout_processing(&select_timeout,
1980                                                &last_timeout_processing_time))
1981                                 return;
1982                         num_smbs = 0; /* Reset smb counter. */
1983                 }
1984
1985
1986                 /*
1987                  * Ensure we do timeout processing if the SMB we just got was
1988                  * only an echo request. This allows us to set the select
1989                  * timeout in 'receive_message_or_smb()' to any value we like
1990                  * without worrying that the client will send echo requests
1991                  * faster than the select timeout, thus starving out the
1992                  * essential processing (change notify, blocking locks) that
1993                  * the timeout code does. JRA.
1994                  */
1995                 num_echos = smb_echo_count;
1996
1997                 process_smb(inbuf, inbuf_len, unread_bytes);
1998
1999                 TALLOC_FREE(inbuf);
2000
2001                 if (smb_echo_count != num_echos) {
2002                         if(!timeout_processing( &select_timeout, &last_timeout_processing_time))
2003                                 return;
2004                         num_smbs = 0; /* Reset smb counter. */
2005                 }
2006
2007                 num_smbs++;
2008
2009                 /*
2010                  * If we are getting smb requests in a constant stream
2011                  * with no echos, make sure we attempt timeout processing
2012                  * every select_timeout milliseconds - but only check for this
2013                  * every 200 smb requests.
2014                  */
2015
2016                 if ((num_smbs % 200) == 0) {
2017                         time_t new_check_time = time(NULL);
2018                         if(new_check_time - last_timeout_processing_time >= (select_timeout/1000)) {
2019                                 if(!timeout_processing(
2020                                            &select_timeout,
2021                                            &last_timeout_processing_time))
2022                                         return;
2023                                 num_smbs = 0; /* Reset smb counter. */
2024                                 last_timeout_processing_time = new_check_time; /* Reset time. */
2025                         }
2026                 }
2027
2028                 /* The timeout_processing function isn't run nearly
2029                    often enough to implement 'max log size' without
2030                    overrunning the size of the file by many megabytes.
2031                    This is especially true if we are running at debug
2032                    level 10.  Checking every 50 SMBs is a nice
2033                    tradeoff of performance vs log file size overrun. */
2034
2035                 if ((num_smbs % 50) == 0 && need_to_check_log_size()) {
2036                         change_to_root_user();
2037                         check_log_size();
2038                 }
2039                 TALLOC_FREE(frame);
2040         }
2041 }