source/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 int smb_echo_count;
  24
  25 /*
  26  * Size of data we can send to client. Set
  27  *  by the client for all protocols above CORE.
  28  *  Set by us for CORE protocol.
  29  */
  30 int max_send = BUFFER_SIZE;
  31 /*
  32  * Size of the data we can receive. Set by us.
  33  * Can be modified by the max xmit parameter.
  34  */
  35 int max_recv = BUFFER_SIZE;
  36
  37 SIG_ATOMIC_T reload_after_sighup = 0;
  38 SIG_ATOMIC_T got_sig_term = 0;
  39 extern bool global_machine_password_needs_changing;
  40 extern int max_send;
  41
  42 /* Accessor function for smb_read_error for smbd functions. */
  43
  44 /****************************************************************************
  45  Send an smb to a fd.
  46 ****************************************************************************/
  47
  48 bool srv_send_smb(int fd, char *buffer, bool do_encrypt)
  49 {
  50         size_t len;
  51         size_t nwritten=0;
  52         ssize_t ret;
  53         char *buf_out = buffer;
  54
  55         /* Sign the outgoing packet if required. */
  56         srv_calculate_sign_mac(buf_out);
  57
  58         if (do_encrypt) {
  59                 NTSTATUS status = srv_encrypt_buffer(buffer, &buf_out);
  60                 if (!NT_STATUS_IS_OK(status)) {
  61                         DEBUG(0, ("send_smb: SMB encryption failed "
  62                                 "on outgoing packet! Error %s\n",
  63                                 nt_errstr(status) ));
  64                         return false;
  65                 }
  66         }
  67
  68         len = smb_len(buf_out) + 4;
  69
  70         while (nwritten < len) {
  71                 ret = write_data(fd,buf_out+nwritten,len - nwritten);
  72                 if (ret <= 0) {
  73                         DEBUG(0,("Error writing %d bytes to client. %d. (%s)\n",
  74                                 (int)len,(int)ret, strerror(errno) ));
  75                         srv_free_enc_buffer(buf_out);
  76                         return false;
  77                 }
  78                 nwritten += ret;
  79         }
  80
  81         srv_free_enc_buffer(buf_out);
  82         return true;
  83 }
  84
  85 /*******************************************************************
  86  Setup the word count and byte count for a smb message.
  87 ********************************************************************/
  88
  89 int srv_set_message(char *buf,
  90                         int num_words,
  91                         int num_bytes,
  92                         bool zero)
  93 {
  94         if (zero && (num_words || num_bytes)) {
  95                 memset(buf + smb_size,'\0',num_words*2 + num_bytes);
  96         }
  97         SCVAL(buf,smb_wct,num_words);
  98         SSVAL(buf,smb_vwv + num_words*SIZEOFWORD,num_bytes);
  99         smb_setlen(buf,(smb_size + num_words*2 + num_bytes - 4));
 100         return (smb_size + num_words*2 + num_bytes);
 101 }
 102
 103 static bool valid_smb_header(const uint8_t *inbuf)
 104 {
 105         if (is_encrypted_packet(inbuf)) {
 106                 return true;
 107         }
 108         return (strncmp(smb_base(inbuf),"\377SMB",4) == 0);
 109 }
 110
 111 /* Socket functions for smbd packet processing. */
 112
 113 static bool valid_packet_size(size_t len)
 114 {
 115         /*
 116          * A WRITEX with CAP_LARGE_WRITEX can be 64k worth of data plus 65 bytes
 117          * of header. Don't print the error if this fits.... JRA.
 118          */
 119
 120         if (len > (BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE)) {
 121                 DEBUG(0,("Invalid packet length! (%lu bytes).\n",
 122                                         (unsigned long)len));
 123                 if (len > BUFFER_SIZE + (SAFETY_MARGIN/2)) {
 124                         return false;
 125                 }
 126         }
 127         return true;
 128 }
 129
 130 static NTSTATUS read_packet_remainder(int fd, char *buffer,
 131                                       unsigned int timeout, ssize_t len)
 132 {
 133         if (len <= 0) {
 134                 return NT_STATUS_OK;
 135         }
 136
 137         return read_socket_with_timeout(fd, buffer, len, len, timeout, NULL);
 138 }
 139
 140 /****************************************************************************
 141  Attempt a zerocopy writeX read. We know here that len > smb_size-4
 142 ****************************************************************************/
 143
 144 /*
 145  * Unfortunately, earlier versions of smbclient/libsmbclient
 146  * don't send this "standard" writeX header. I've fixed this
 147  * for 3.2 but we'll use the old method with earlier versions.
 148  * Windows and CIFSFS at least use this standard size. Not
 149  * sure about MacOSX.
 150  */
 151
 152 #define STANDARD_WRITE_AND_X_HEADER_SIZE (smb_size - 4 + /* basic header */ \
 153                                 (2*14) + /* word count (including bcc) */ \
 154                                 1 /* pad byte */)
 155
 156 static NTSTATUS receive_smb_raw_talloc_partial_read(TALLOC_CTX *mem_ctx,
 157                                                     const char lenbuf[4],
 158                                                     int fd, char **buffer,
 159                                                     unsigned int timeout,
 160                                                     size_t *p_unread,
 161                                                     size_t *len_ret)
 162 {
 163         /* Size of a WRITEX call (+4 byte len). */
 164         char writeX_header[4 + STANDARD_WRITE_AND_X_HEADER_SIZE];
 165         ssize_t len = smb_len_large(lenbuf); /* Could be a UNIX large writeX. */
 166         ssize_t toread;
 167         NTSTATUS status;
 168
 169         memcpy(writeX_header, lenbuf, sizeof(lenbuf));
 170
 171         status = read_socket_with_timeout(
 172                 fd, writeX_header + 4,
 173                 STANDARD_WRITE_AND_X_HEADER_SIZE,
 174                 STANDARD_WRITE_AND_X_HEADER_SIZE,
 175                 timeout, NULL);
 176
 177         if (!NT_STATUS_IS_OK(status)) {
 178                 return status;
 179         }
 180
 181         /*
 182          * Ok - now try and see if this is a possible
 183          * valid writeX call.
 184          */
 185
 186         if (is_valid_writeX_buffer((uint8_t *)writeX_header)) {
 187                 /*
 188                  * If the data offset is beyond what
 189                  * we've read, drain the extra bytes.
 190                  */
 191                 uint16_t doff = SVAL(writeX_header,smb_vwv11);
 192                 ssize_t newlen;
 193
 194                 if (doff > STANDARD_WRITE_AND_X_HEADER_SIZE) {
 195                         size_t drain = doff - STANDARD_WRITE_AND_X_HEADER_SIZE;
 196                         if (drain_socket(smbd_server_fd(), drain) != drain) {
 197                                 smb_panic("receive_smb_raw_talloc_partial_read:"
 198                                         " failed to drain pending bytes");
 199                         }
 200                 } else {
 201                         doff = STANDARD_WRITE_AND_X_HEADER_SIZE;
 202                 }
 203
 204                 /* Spoof down the length and null out the bcc. */
 205                 set_message_bcc(writeX_header, 0);
 206                 newlen = smb_len(writeX_header);
 207
 208                 /* Copy the header we've written. */
 209
 210                 *buffer = (char *)TALLOC_MEMDUP(mem_ctx,
 211                                 writeX_header,
 212                                 sizeof(writeX_header));
 213
 214                 if (*buffer == NULL) {
 215                         DEBUG(0, ("Could not allocate inbuf of length %d\n",
 216                                   (int)sizeof(writeX_header)));
 217                         return NT_STATUS_NO_MEMORY;
 218                 }
 219
 220                 /* Work out the remaining bytes. */
 221                 *p_unread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
 222                 *len_ret = newlen + 4;
 223                 return NT_STATUS_OK;
 224         }
 225
 226         if (!valid_packet_size(len)) {
 227                 return NT_STATUS_INVALID_PARAMETER;
 228         }
 229
 230         /*
 231          * Not a valid writeX call. Just do the standard
 232          * talloc and return.
 233          */
 234
 235         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
 236
 237         if (*buffer == NULL) {
 238                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
 239                           (int)len+4));
 240                 return NT_STATUS_NO_MEMORY;
 241         }
 242
 243         /* Copy in what we already read. */
 244         memcpy(*buffer,
 245                 writeX_header,
 246                 4 + STANDARD_WRITE_AND_X_HEADER_SIZE);
 247         toread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
 248
 249         if(toread > 0) {
 250                 status = read_packet_remainder(
 251                         fd, (*buffer) + 4 + STANDARD_WRITE_AND_X_HEADER_SIZE,
 252                         timeout, toread);
 253
 254                 if (!NT_STATUS_IS_OK(status)) {
 255                         return status;
 256                 }
 257         }
 258
 259         *len_ret = len + 4;
 260         return NT_STATUS_OK;
 261 }
 262
 263 static NTSTATUS receive_smb_raw_talloc(TALLOC_CTX *mem_ctx, int fd,
 264                                        char **buffer, unsigned int timeout,
 265                                        size_t *p_unread, size_t *plen)
 266 {
 267         char lenbuf[4];
 268         size_t len;
 269         int min_recv_size = lp_min_receive_file_size();
 270         NTSTATUS status;
 271
 272         *p_unread = 0;
 273
 274         status = read_smb_length_return_keepalive(fd, lenbuf, timeout, &len);
 275         if (!NT_STATUS_IS_OK(status)) {
 276                 DEBUG(10, ("receive_smb_raw: %s\n", nt_errstr(status)));
 277                 return status;
 278         }
 279
 280         if (CVAL(lenbuf,0) == 0 &&
 281                         min_recv_size &&
 282                         smb_len_large(lenbuf) > min_recv_size && /* Could be a UNIX large writeX. */
 283                         !srv_is_signing_active()) {
 284
 285                 status = receive_smb_raw_talloc_partial_read(
 286                         mem_ctx, lenbuf, fd, buffer, timeout, p_unread, &len);
 287
 288                 if (!NT_STATUS_IS_OK(status)) {
 289                         DEBUG(10, ("receive_smb_raw: %s\n",
 290                                    nt_errstr(status)));
 291                         return status;
 292                 }
 293         }
 294
 295         if (!valid_packet_size(len)) {
 296                 return NT_STATUS_INVALID_PARAMETER;
 297         }
 298
 299         /*
 300          * The +4 here can't wrap, we've checked the length above already.
 301          */
 302
 303         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
 304
 305         if (*buffer == NULL) {
 306                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
 307                           (int)len+4));
 308                 return NT_STATUS_NO_MEMORY;
 309         }
 310
 311         memcpy(*buffer, lenbuf, sizeof(lenbuf));
 312
 313         status = read_packet_remainder(fd, (*buffer)+4, timeout, len);
 314         if (!NT_STATUS_IS_OK(status)) {
 315                 return status;
 316         }
 317
 318         *plen = len + 4;
 319         return NT_STATUS_OK;
 320 }
 321
 322 static NTSTATUS receive_smb_talloc(TALLOC_CTX *mem_ctx, int fd,
 323                                    char **buffer, unsigned int timeout,
 324                                    size_t *p_unread, bool *p_encrypted,
 325                                    size_t *p_len)
 326 {
 327         size_t len = 0;
 328         NTSTATUS status;
 329
 330         *p_encrypted = false;
 331
 332         status = receive_smb_raw_talloc(mem_ctx, fd, buffer, timeout,
 333                                         p_unread, &len);
 334         if (!NT_STATUS_IS_OK(status)) {
 335                 return status;
 336         }
 337
 338         if (is_encrypted_packet((uint8_t *)*buffer)) {
 339                 status = srv_decrypt_buffer(*buffer);
 340                 if (!NT_STATUS_IS_OK(status)) {
 341                         DEBUG(0, ("receive_smb_talloc: SMB decryption failed on "
 342                                 "incoming packet! Error %s\n",
 343                                 nt_errstr(status) ));
 344                         return status;
 345                 }
 346                 *p_encrypted = true;
 347         }
 348
 349         /* Check the incoming SMB signature. */
 350         if (!srv_check_sign_mac(*buffer, true)) {
 351                 DEBUG(0, ("receive_smb: SMB Signature verification failed on "
 352                           "incoming packet!\n"));
 353                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
 354         }
 355
 356         *p_len = len;
 357         return NT_STATUS_OK;
 358 }
 359
 360 /*
 361  * Initialize a struct smb_request from an inbuf
 362  */
 363
 364 void init_smb_request(struct smb_request *req,
 365                         const uint8 *inbuf,
 366                         size_t unread_bytes,
 367                         bool encrypted)
 368 {
 369         size_t req_size = smb_len(inbuf) + 4;
 370         /* Ensure we have at least smb_size bytes. */
 371         if (req_size < smb_size) {
 372                 DEBUG(0,("init_smb_request: invalid request size %u\n",
 373                         (unsigned int)req_size ));
 374                 exit_server_cleanly("Invalid SMB request");
 375         }
 376         req->flags2 = SVAL(inbuf, smb_flg2);
 377         req->smbpid = SVAL(inbuf, smb_pid);
 378         req->mid    = SVAL(inbuf, smb_mid);
 379         req->vuid   = SVAL(inbuf, smb_uid);
 380         req->tid    = SVAL(inbuf, smb_tid);
 381         req->wct    = CVAL(inbuf, smb_wct);
 382         req->unread_bytes = unread_bytes;
 383         req->encrypted = encrypted;
 384         req->conn = conn_find(req->tid);
 385
 386         /* Ensure we have at least wct words and 2 bytes of bcc. */
 387         if (smb_size + req->wct*2 > req_size) {
 388                 DEBUG(0,("init_smb_request: invalid wct number %u (size %u)\n",
 389                         (unsigned int)req->wct,
 390                         (unsigned int)req_size));
 391                 exit_server_cleanly("Invalid SMB request");
 392         }
 393         /* Ensure bcc is correct. */
 394         if (((uint8 *)smb_buf(inbuf)) + smb_buflen(inbuf) > inbuf + req_size) {
 395                 DEBUG(0,("init_smb_request: invalid bcc number %u "
 396                         "(wct = %u, size %u)\n",
 397                         (unsigned int)smb_buflen(inbuf),
 398                         (unsigned int)req->wct,
 399                         (unsigned int)req_size));
 400                 exit_server_cleanly("Invalid SMB request");
 401         }
 402         req->inbuf  = inbuf;
 403         req->outbuf = NULL;
 404 }
 405
 406 /****************************************************************************
 407  structure to hold a linked list of queued messages.
 408  for processing.
 409 ****************************************************************************/
 410
 411 static struct pending_message_list *deferred_open_queue;
 412
 413 /****************************************************************************
 414  Function to push a message onto the tail of a linked list of smb messages ready
 415  for processing.
 416 ****************************************************************************/
 417
 418 static bool push_queued_message(struct smb_request *req,
 419                                 struct timeval request_time,
 420                                 struct timeval end_time,
 421                                 char *private_data, size_t private_len)
 422 {
 423         int msg_len = smb_len(req->inbuf) + 4;
 424         struct pending_message_list *msg;
 425
 426         msg = TALLOC_ZERO_P(NULL, struct pending_message_list);
 427
 428         if(msg == NULL) {
 429                 DEBUG(0,("push_message: malloc fail (1)\n"));
 430                 return False;
 431         }
 432
 433         msg->buf = data_blob_talloc(msg, req->inbuf, msg_len);
 434         if(msg->buf.data == NULL) {
 435                 DEBUG(0,("push_message: malloc fail (2)\n"));
 436                 TALLOC_FREE(msg);
 437                 return False;
 438         }
 439
 440         msg->request_time = request_time;
 441         msg->end_time = end_time;
 442         msg->encrypted = req->encrypted;
 443
 444         if (private_data) {
 445                 msg->private_data = data_blob_talloc(msg, private_data,
 446                                                      private_len);
 447                 if (msg->private_data.data == NULL) {
 448                         DEBUG(0,("push_message: malloc fail (3)\n"));
 449                         TALLOC_FREE(msg);
 450                         return False;
 451                 }
 452         }
 453
 454         DLIST_ADD_END(deferred_open_queue, msg, struct pending_message_list *);
 455
 456         DEBUG(10,("push_message: pushed message length %u on "
 457                   "deferred_open_queue\n", (unsigned int)msg_len));
 458
 459         return True;
 460 }
 461
 462 /****************************************************************************
 463  Function to delete a sharing violation open message by mid.
 464 ****************************************************************************/
 465
 466 void remove_deferred_open_smb_message(uint16 mid)
 467 {
 468         struct pending_message_list *pml;
 469
 470         for (pml = deferred_open_queue; pml; pml = pml->next) {
 471                 if (mid == SVAL(pml->buf.data,smb_mid)) {
 472                         DEBUG(10,("remove_sharing_violation_open_smb_message: "
 473                                   "deleting mid %u len %u\n",
 474                                   (unsigned int)mid,
 475                                   (unsigned int)pml->buf.length ));
 476                         DLIST_REMOVE(deferred_open_queue, pml);
 477                         TALLOC_FREE(pml);
 478                         return;
 479                 }
 480         }
 481 }
 482
 483 /****************************************************************************
 484  Move a sharing violation open retry message to the front of the list and
 485  schedule it for immediate processing.
 486 ****************************************************************************/
 487
 488 void schedule_deferred_open_smb_message(uint16 mid)
 489 {
 490         struct pending_message_list *pml;
 491         int i = 0;
 492
 493         for (pml = deferred_open_queue; pml; pml = pml->next) {
 494                 uint16 msg_mid = SVAL(pml->buf.data,smb_mid);
 495                 DEBUG(10,("schedule_deferred_open_smb_message: [%d] msg_mid = %u\n", i++,
 496                         (unsigned int)msg_mid ));
 497                 if (mid == msg_mid) {
 498                         DEBUG(10,("schedule_deferred_open_smb_message: scheduling mid %u\n",
 499                                 mid ));
 500                         pml->end_time.tv_sec = 0;
 501                         pml->end_time.tv_usec = 0;
 502                         DLIST_PROMOTE(deferred_open_queue, pml);
 503                         return;
 504                 }
 505         }
 506
 507         DEBUG(10,("schedule_deferred_open_smb_message: failed to find message mid %u\n",
 508                 mid ));
 509 }
 510
 511 /****************************************************************************
 512  Return true if this mid is on the deferred queue.
 513 ****************************************************************************/
 514
 515 bool open_was_deferred(uint16 mid)
 516 {
 517         struct pending_message_list *pml;
 518
 519         for (pml = deferred_open_queue; pml; pml = pml->next) {
 520                 if (SVAL(pml->buf.data,smb_mid) == mid) {
 521                         return True;
 522                 }
 523         }
 524         return False;
 525 }
 526
 527 /****************************************************************************
 528  Return the message queued by this mid.
 529 ****************************************************************************/
 530
 531 struct pending_message_list *get_open_deferred_message(uint16 mid)
 532 {
 533         struct pending_message_list *pml;
 534
 535         for (pml = deferred_open_queue; pml; pml = pml->next) {
 536                 if (SVAL(pml->buf.data,smb_mid) == mid) {
 537                         return pml;
 538                 }
 539         }
 540         return NULL;
 541 }
 542
 543 /****************************************************************************
 544  Function to push a deferred open smb message onto a linked list of local smb
 545  messages ready for processing.
 546 ****************************************************************************/
 547
 548 bool push_deferred_smb_message(struct smb_request *req,
 549                                struct timeval request_time,
 550                                struct timeval timeout,
 551                                char *private_data, size_t priv_len)
 552 {
 553         struct timeval end_time;
 554
 555         if (req->unread_bytes) {
 556                 DEBUG(0,("push_deferred_smb_message: logic error ! "
 557                         "unread_bytes = %u\n",
 558                         (unsigned int)req->unread_bytes ));
 559                 smb_panic("push_deferred_smb_message: "
 560                         "logic error unread_bytes != 0" );
 561         }
 562
 563         end_time = timeval_sum(&request_time, &timeout);
 564
 565         DEBUG(10,("push_deferred_open_smb_message: pushing message len %u mid %u "
 566                   "timeout time [%u.%06u]\n",
 567                   (unsigned int) smb_len(req->inbuf)+4, (unsigned int)req->mid,
 568                   (unsigned int)end_time.tv_sec,
 569                   (unsigned int)end_time.tv_usec));
 570
 571         return push_queued_message(req, request_time, end_time,
 572                                    private_data, priv_len);
 573 }
 574
 575 struct idle_event {
 576         struct timed_event *te;
 577         struct timeval interval;
 578         char *name;
 579         bool (*handler)(const struct timeval *now, void *private_data);
 580         void *private_data;
 581 };
 582
 583 static void idle_event_handler(struct event_context *ctx,
 584                                struct timed_event *te,
 585                                const struct timeval *now,
 586                                void *private_data)
 587 {
 588         struct idle_event *event =
 589                 talloc_get_type_abort(private_data, struct idle_event);
 590
 591         TALLOC_FREE(event->te);
 592
 593         if (!event->handler(now, event->private_data)) {
 594                 /* Don't repeat, delete ourselves */
 595                 TALLOC_FREE(event);
 596                 return;
 597         }
 598
 599         event->te = event_add_timed(ctx, event,
 600                                     timeval_sum(now, &event->interval),
 601                                     event->name,
 602                                     idle_event_handler, event);
 603
 604         /* We can't do much but fail here. */
 605         SMB_ASSERT(event->te != NULL);
 606 }
 607
 608 struct idle_event *event_add_idle(struct event_context *event_ctx,
 609                                   TALLOC_CTX *mem_ctx,
 610                                   struct timeval interval,
 611                                   const char *name,
 612                                   bool (*handler)(const struct timeval *now,
 613                                                   void *private_data),
 614                                   void *private_data)
 615 {
 616         struct idle_event *result;
 617         struct timeval now = timeval_current();
 618
 619         result = TALLOC_P(mem_ctx, struct idle_event);
 620         if (result == NULL) {
 621                 DEBUG(0, ("talloc failed\n"));
 622                 return NULL;
 623         }
 624
 625         result->interval = interval;
 626         result->handler = handler;
 627         result->private_data = private_data;
 628
 629         if (!(result->name = talloc_asprintf(result, "idle_evt(%s)", name))) {
 630                 DEBUG(0, ("talloc failed\n"));
 631                 TALLOC_FREE(result);
 632                 return NULL;
 633         }
 634
 635         result->te = event_add_timed(event_ctx, result,
 636                                      timeval_sum(&now, &interval),
 637                                      result->name,
 638                                      idle_event_handler, result);
 639         if (result->te == NULL) {
 640                 DEBUG(0, ("event_add_timed failed\n"));
 641                 TALLOC_FREE(result);
 642                 return NULL;
 643         }
 644
 645         return result;
 646 }
 647
 648 /****************************************************************************
 649  Do all async processing in here. This includes kernel oplock messages, change
 650  notify events etc.
 651 ****************************************************************************/
 652
 653 static void async_processing(fd_set *pfds)
 654 {
 655         DEBUG(10,("async_processing: Doing async processing.\n"));
 656
 657         process_aio_queue();
 658
 659         process_kernel_oplocks(smbd_messaging_context(), pfds);
 660
 661         /* Do the aio check again after receive_local_message as it does a
 662            select and may have eaten our signal. */
 663         /* Is this till true? -- vl */
 664         process_aio_queue();
 665
 666         if (got_sig_term) {
 667                 exit_server_cleanly("termination signal");
 668         }
 669
 670         /* check for sighup processing */
 671         if (reload_after_sighup) {
 672                 change_to_root_user();
 673                 DEBUG(1,("Reloading services after SIGHUP\n"));
 674                 reload_services(False);
 675                 reload_after_sighup = 0;
 676         }
 677 }
 678
 679 /****************************************************************************
 680  Add a fd to the set we will be select(2)ing on.
 681 ****************************************************************************/
 682
 683 static int select_on_fd(int fd, int maxfd, fd_set *fds)
 684 {
 685         if (fd != -1) {
 686                 FD_SET(fd, fds);
 687                 maxfd = MAX(maxfd, fd);
 688         }
 689
 690         return maxfd;
 691 }
 692
 693 /****************************************************************************
 694   Do a select on an two fd's - with timeout.
 695
 696   If a local udp message has been pushed onto the
 697   queue (this can only happen during oplock break
 698   processing) call async_processing()
 699
 700   If a pending smb message has been pushed onto the
 701   queue (this can only happen during oplock break
 702   processing) return this next.
 703
 704   If the first smbfd is ready then read an smb from it.
 705   if the second (loopback UDP) fd is ready then read a message
 706   from it and setup the buffer header to identify the length
 707   and from address.
 708   Returns False on timeout or error.
 709   Else returns True.
 710
 711 The timeout is in milliseconds
 712 ****************************************************************************/
 713
 714 static NTSTATUS receive_message_or_smb(TALLOC_CTX *mem_ctx, char **buffer,
 715                                        size_t *buffer_len, int timeout,
 716                                        size_t *p_unread, bool *p_encrypted)
 717 {
 718         fd_set r_fds, w_fds;
 719         int selrtn;
 720         struct timeval to;
 721         int maxfd = 0;
 722         size_t len = 0;
 723         NTSTATUS status;
 724
 725         *p_unread = 0;
 726
 727  again:
 728
 729         if (timeout >= 0) {
 730                 to.tv_sec = timeout / 1000;
 731                 to.tv_usec = (timeout % 1000) * 1000;
 732         } else {
 733                 to.tv_sec = SMBD_SELECT_TIMEOUT;
 734                 to.tv_usec = 0;
 735         }
 736
 737         /*
 738          * Note that this call must be before processing any SMB
 739          * messages as we need to synchronously process any messages
 740          * we may have sent to ourselves from the previous SMB.
 741          */
 742         message_dispatch(smbd_messaging_context());
 743
 744         /*
 745          * Check to see if we already have a message on the deferred open queue
 746          * and it's time to schedule.
 747          */
 748         if(deferred_open_queue != NULL) {
 749                 bool pop_message = False;
 750                 struct pending_message_list *msg = deferred_open_queue;
 751
 752                 if (timeval_is_zero(&msg->end_time)) {
 753                         pop_message = True;
 754                 } else {
 755                         struct timeval tv;
 756                         SMB_BIG_INT tdif;
 757
 758                         GetTimeOfDay(&tv);
 759                         tdif = usec_time_diff(&msg->end_time, &tv);
 760                         if (tdif <= 0) {
 761                                 /* Timed out. Schedule...*/
 762                                 pop_message = True;
 763                                 DEBUG(10,("receive_message_or_smb: queued message timed out.\n"));
 764                         } else {
 765                                 /* Make a more accurate select timeout. */
 766                                 to.tv_sec = tdif / 1000000;
 767                                 to.tv_usec = tdif % 1000000;
 768                                 DEBUG(10,("receive_message_or_smb: select with timeout of [%u.%06u]\n",
 769                                         (unsigned int)to.tv_sec, (unsigned int)to.tv_usec ));
 770                         }
 771                 }
 772
 773                 if (pop_message) {
 774
 775                         *buffer = (char *)talloc_memdup(mem_ctx, msg->buf.data,
 776                                                         msg->buf.length);
 777                         if (*buffer == NULL) {
 778                                 DEBUG(0, ("talloc failed\n"));
 779                                 return NT_STATUS_NO_MEMORY;
 780                         }
 781                         *buffer_len = msg->buf.length;
 782                         *p_encrypted = msg->encrypted;
 783
 784                         /* We leave this message on the queue so the open code can
 785                            know this is a retry. */
 786                         DEBUG(5,("receive_message_or_smb: returning deferred open smb message.\n"));
 787                         return NT_STATUS_OK;
 788                 }
 789         }
 790
 791         /*
 792          * Setup the select fd sets.
 793          */
 794
 795         FD_ZERO(&r_fds);
 796         FD_ZERO(&w_fds);
 797
 798         /*
 799          * Ensure we process oplock break messages by preference.
 800          * We have to do this before the select, after the select
 801          * and if the select returns EINTR. This is due to the fact
 802          * that the selects called from async_processing can eat an EINTR
 803          * caused by a signal (we can't take the break message there).
 804          * This is hideously complex - *MUST* be simplified for 3.0 ! JRA.
 805          */
 806
 807         if (oplock_message_waiting(&r_fds)) {
 808                 DEBUG(10,("receive_message_or_smb: oplock_message is waiting.\n"));
 809                 async_processing(&r_fds);
 810                 /*
 811                  * After async processing we must go and do the select again, as
 812                  * the state of the flag in fds for the server file descriptor is
 813                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 814                  */
 815                 goto again;
 816         }
 817
 818         /*
 819          * Are there any timed events waiting ? If so, ensure we don't
 820          * select for longer than it would take to wait for them.
 821          */
 822
 823         {
 824                 struct timeval now;
 825                 GetTimeOfDay(&now);
 826
 827                 event_add_to_select_args(smbd_event_context(), &now,
 828                                          &r_fds, &w_fds, &to, &maxfd);
 829         }
 830
 831         if (timeval_is_zero(&to)) {
 832                 /* Process a timed event now... */
 833                 if (run_events(smbd_event_context(), 0, NULL, NULL)) {
 834                         goto again;
 835                 }
 836         }
 837
 838         {
 839                 int sav;
 840                 START_PROFILE(smbd_idle);
 841
 842                 maxfd = select_on_fd(smbd_server_fd(), maxfd, &r_fds);
 843                 maxfd = select_on_fd(oplock_notify_fd(), maxfd, &r_fds);
 844
 845                 selrtn = sys_select(maxfd+1,&r_fds,&w_fds,NULL,&to);
 846                 sav = errno;
 847
 848                 END_PROFILE(smbd_idle);
 849                 errno = sav;
 850         }
 851
 852         if (run_events(smbd_event_context(), selrtn, &r_fds, &w_fds)) {
 853                 goto again;
 854         }
 855
 856         /*
 857          * We've just woken up from a protentially long select sleep.
 858          * Ensure we process local messages as we need to synchronously
 859          * process any messages from other smbd's to avoid file rename race
 860          * conditions. This call is cheap if there are no messages waiting.
 861          * JRA.
 862          */
 863         message_dispatch(smbd_messaging_context());
 864
 865         /* if we get EINTR then maybe we have received an oplock
 866            signal - treat this as select returning 1. This is ugly, but
 867            is the best we can do until the oplock code knows more about
 868            signals */
 869         if (selrtn == -1 && errno == EINTR) {
 870                 async_processing(&r_fds);
 871                 /*
 872                  * After async processing we must go and do the select again, as
 873                  * the state of the flag in fds for the server file descriptor is
 874                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 875                  */
 876                 goto again;
 877         }
 878
 879         /* Check if error */
 880         if (selrtn == -1) {
 881                 /* something is wrong. Maybe the socket is dead? */
 882                 return map_nt_error_from_unix(errno);
 883         }
 884
 885         /* Did we timeout ? */
 886         if (selrtn == 0) {
 887                 return NT_STATUS_IO_TIMEOUT;
 888         }
 889
 890         /*
 891          * Ensure we process oplock break messages by preference.
 892          * This is IMPORTANT ! Otherwise we can starve other processes
 893          * sending us an oplock break message. JRA.
 894          */
 895
 896         if (oplock_message_waiting(&r_fds)) {
 897                 async_processing(&r_fds);
 898                 /*
 899                  * After async processing we must go and do the select again, as
 900                  * the state of the flag in fds for the server file descriptor is
 901                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 902                  */
 903                 goto again;
 904         }
 905
 906         status = receive_smb_talloc(mem_ctx, smbd_server_fd(), buffer, 0,
 907                                     p_unread, p_encrypted, &len);
 908
 909         if (!NT_STATUS_IS_OK(status)) {
 910                 return status;
 911         }
 912
 913         *buffer_len = len;
 914
 915         return NT_STATUS_OK;
 916 }
 917
 918 /*
 919  * Only allow 5 outstanding trans requests. We're allocating memory, so
 920  * prevent a DoS.
 921  */
 922
 923 NTSTATUS allow_new_trans(struct trans_state *list, int mid)
 924 {
 925         int count = 0;
 926         for (; list != NULL; list = list->next) {
 927
 928                 if (list->mid == mid) {
 929                         return NT_STATUS_INVALID_PARAMETER;
 930                 }
 931
 932                 count += 1;
 933         }
 934         if (count > 5) {
 935                 return NT_STATUS_INSUFFICIENT_RESOURCES;
 936         }
 937
 938         return NT_STATUS_OK;
 939 }
 940
 941 /****************************************************************************
 942  We're terminating and have closed all our files/connections etc.
 943  If there are any pending local messages we need to respond to them
 944  before termination so that other smbds don't think we just died whilst
 945  holding oplocks.
 946 ****************************************************************************/
 947
 948 void respond_to_all_remaining_local_messages(void)
 949 {
 950         /*
 951          * Assert we have no exclusive open oplocks.
 952          */
 953
 954         if(get_number_of_exclusive_open_oplocks()) {
 955                 DEBUG(0,("respond_to_all_remaining_local_messages: PANIC : we have %d exclusive oplocks.\n",
 956                         get_number_of_exclusive_open_oplocks() ));
 957                 return;
 958         }
 959
 960         process_kernel_oplocks(smbd_messaging_context(), NULL);
 961
 962         return;
 963 }
 964
 965
 966 /*
 967 These flags determine some of the permissions required to do an operation
 968
 969 Note that I don't set NEED_WRITE on some write operations because they
 970 are used by some brain-dead clients when printing, and I don't want to
 971 force write permissions on print services.
 972 */
 973 #define AS_USER (1<<0)
 974 #define NEED_WRITE (1<<1) /* Must be paired with AS_USER */
 975 #define TIME_INIT (1<<2)
 976 #define CAN_IPC (1<<3) /* Must be paired with AS_USER */
 977 #define AS_GUEST (1<<5) /* Must *NOT* be paired with AS_USER */
 978 #define DO_CHDIR (1<<6)
 979
 980 /*
 981    define a list of possible SMB messages and their corresponding
 982    functions. Any message that has a NULL function is unimplemented -
 983    please feel free to contribute implementations!
 984 */
 985 static const struct smb_message_struct {
 986         const char *name;
 987         void (*fn_new)(struct smb_request *req);
 988         int flags;
 989 } smb_messages[256] = {
 990
 991 /* 0x00 */ { "SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE},
 992 /* 0x01 */ { "SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE},
 993 /* 0x02 */ { "SMBopen",reply_open,AS_USER },
 994 /* 0x03 */ { "SMBcreate",reply_mknew,AS_USER},
 995 /* 0x04 */ { "SMBclose",reply_close,AS_USER | CAN_IPC },
 996 /* 0x05 */ { "SMBflush",reply_flush,AS_USER},
 997 /* 0x06 */ { "SMBunlink",reply_unlink,AS_USER | NEED_WRITE },
 998 /* 0x07 */ { "SMBmv",reply_mv,AS_USER | NEED_WRITE },
 999 /* 0x08 */ { "SMBgetatr",reply_getatr,AS_USER},
1000 /* 0x09 */ { "SMBsetatr",reply_setatr,AS_USER | NEED_WRITE},
1001 /* 0x0a */ { "SMBread",reply_read,AS_USER},
1002 /* 0x0b */ { "SMBwrite",reply_write,AS_USER | CAN_IPC },
1003 /* 0x0c */ { "SMBlock",reply_lock,AS_USER},
1004 /* 0x0d */ { "SMBunlock",reply_unlock,AS_USER},
1005 /* 0x0e */ { "SMBctemp",reply_ctemp,AS_USER },
1006 /* 0x0f */ { "SMBmknew",reply_mknew,AS_USER},
1007 /* 0x10 */ { "SMBcheckpath",reply_checkpath,AS_USER},
1008 /* 0x11 */ { "SMBexit",reply_exit,DO_CHDIR},
1009 /* 0x12 */ { "SMBlseek",reply_lseek,AS_USER},
1010 /* 0x13 */ { "SMBlockread",reply_lockread,AS_USER},
1011 /* 0x14 */ { "SMBwriteunlock",reply_writeunlock,AS_USER},
1012 /* 0x15 */ { NULL, NULL, 0 },
1013 /* 0x16 */ { NULL, NULL, 0 },
1014 /* 0x17 */ { NULL, NULL, 0 },
1015 /* 0x18 */ { NULL, NULL, 0 },
1016 /* 0x19 */ { NULL, NULL, 0 },
1017 /* 0x1a */ { "SMBreadbraw",reply_readbraw,AS_USER},
1018 /* 0x1b */ { "SMBreadBmpx",reply_readbmpx,AS_USER},
1019 /* 0x1c */ { "SMBreadBs",reply_readbs,AS_USER },
1020 /* 0x1d */ { "SMBwritebraw",reply_writebraw,AS_USER},
1021 /* 0x1e */ { "SMBwriteBmpx",reply_writebmpx,AS_USER},
1022 /* 0x1f */ { "SMBwriteBs",reply_writebs,AS_USER},
1023 /* 0x20 */ { "SMBwritec", NULL,0},
1024 /* 0x21 */ { NULL, NULL, 0 },
1025 /* 0x22 */ { "SMBsetattrE",reply_setattrE,AS_USER | NEED_WRITE },
1026 /* 0x23 */ { "SMBgetattrE",reply_getattrE,AS_USER },
1027 /* 0x24 */ { "SMBlockingX",reply_lockingX,AS_USER },
1028 /* 0x25 */ { "SMBtrans",reply_trans,AS_USER | CAN_IPC },
1029 /* 0x26 */ { "SMBtranss",reply_transs,AS_USER | CAN_IPC},
1030 /* 0x27 */ { "SMBioctl",reply_ioctl,0},
1031 /* 0x28 */ { "SMBioctls", NULL,AS_USER},
1032 /* 0x29 */ { "SMBcopy",reply_copy,AS_USER | NEED_WRITE },
1033 /* 0x2a */ { "SMBmove", NULL,AS_USER | NEED_WRITE },
1034 /* 0x2b */ { "SMBecho",reply_echo,0},
1035 /* 0x2c */ { "SMBwriteclose",reply_writeclose,AS_USER},
1036 /* 0x2d */ { "SMBopenX",reply_open_and_X,AS_USER | CAN_IPC },
1037 /* 0x2e */ { "SMBreadX",reply_read_and_X,AS_USER | CAN_IPC },
1038 /* 0x2f */ { "SMBwriteX",reply_write_and_X,AS_USER | CAN_IPC },
1039 /* 0x30 */ { NULL, NULL, 0 },
1040 /* 0x31 */ { NULL, NULL, 0 },
1041 /* 0x32 */ { "SMBtrans2",reply_trans2, AS_USER | CAN_IPC },
1042 /* 0x33 */ { "SMBtranss2",reply_transs2, AS_USER},
1043 /* 0x34 */ { "SMBfindclose",reply_findclose,AS_USER},
1044 /* 0x35 */ { "SMBfindnclose",reply_findnclose,AS_USER},
1045 /* 0x36 */ { NULL, NULL, 0 },
1046 /* 0x37 */ { NULL, NULL, 0 },
1047 /* 0x38 */ { NULL, NULL, 0 },
1048 /* 0x39 */ { NULL, NULL, 0 },
1049 /* 0x3a */ { NULL, NULL, 0 },
1050 /* 0x3b */ { NULL, NULL, 0 },
1051 /* 0x3c */ { NULL, NULL, 0 },
1052 /* 0x3d */ { NULL, NULL, 0 },
1053 /* 0x3e */ { NULL, NULL, 0 },
1054 /* 0x3f */ { NULL, NULL, 0 },
1055 /* 0x40 */ { NULL, NULL, 0 },
1056 /* 0x41 */ { NULL, NULL, 0 },
1057 /* 0x42 */ { NULL, NULL, 0 },
1058 /* 0x43 */ { NULL, NULL, 0 },
1059 /* 0x44 */ { NULL, NULL, 0 },
1060 /* 0x45 */ { NULL, NULL, 0 },
1061 /* 0x46 */ { NULL, NULL, 0 },
1062 /* 0x47 */ { NULL, NULL, 0 },
1063 /* 0x48 */ { NULL, NULL, 0 },
1064 /* 0x49 */ { NULL, NULL, 0 },
1065 /* 0x4a */ { NULL, NULL, 0 },
1066 /* 0x4b */ { NULL, NULL, 0 },
1067 /* 0x4c */ { NULL, NULL, 0 },
1068 /* 0x4d */ { NULL, NULL, 0 },
1069 /* 0x4e */ { NULL, NULL, 0 },
1070 /* 0x4f */ { NULL, NULL, 0 },
1071 /* 0x50 */ { NULL, NULL, 0 },
1072 /* 0x51 */ { NULL, NULL, 0 },
1073 /* 0x52 */ { NULL, NULL, 0 },
1074 /* 0x53 */ { NULL, NULL, 0 },
1075 /* 0x54 */ { NULL, NULL, 0 },
1076 /* 0x55 */ { NULL, NULL, 0 },
1077 /* 0x56 */ { NULL, NULL, 0 },
1078 /* 0x57 */ { NULL, NULL, 0 },
1079 /* 0x58 */ { NULL, NULL, 0 },
1080 /* 0x59 */ { NULL, NULL, 0 },
1081 /* 0x5a */ { NULL, NULL, 0 },
1082 /* 0x5b */ { NULL, NULL, 0 },
1083 /* 0x5c */ { NULL, NULL, 0 },
1084 /* 0x5d */ { NULL, NULL, 0 },
1085 /* 0x5e */ { NULL, NULL, 0 },
1086 /* 0x5f */ { NULL, NULL, 0 },
1087 /* 0x60 */ { NULL, NULL, 0 },
1088 /* 0x61 */ { NULL, NULL, 0 },
1089 /* 0x62 */ { NULL, NULL, 0 },
1090 /* 0x63 */ { NULL, NULL, 0 },
1091 /* 0x64 */ { NULL, NULL, 0 },
1092 /* 0x65 */ { NULL, NULL, 0 },
1093 /* 0x66 */ { NULL, NULL, 0 },
1094 /* 0x67 */ { NULL, NULL, 0 },
1095 /* 0x68 */ { NULL, NULL, 0 },
1096 /* 0x69 */ { NULL, NULL, 0 },
1097 /* 0x6a */ { NULL, NULL, 0 },
1098 /* 0x6b */ { NULL, NULL, 0 },
1099 /* 0x6c */ { NULL, NULL, 0 },
1100 /* 0x6d */ { NULL, NULL, 0 },
1101 /* 0x6e */ { NULL, NULL, 0 },
1102 /* 0x6f */ { NULL, NULL, 0 },
1103 /* 0x70 */ { "SMBtcon",reply_tcon,0},
1104 /* 0x71 */ { "SMBtdis",reply_tdis,DO_CHDIR},
1105 /* 0x72 */ { "SMBnegprot",reply_negprot,0},
1106 /* 0x73 */ { "SMBsesssetupX",reply_sesssetup_and_X,0},
1107 /* 0x74 */ { "SMBulogoffX",reply_ulogoffX, 0}, /* ulogoff doesn't give a valid TID */
1108 /* 0x75 */ { "SMBtconX",reply_tcon_and_X,0},
1109 /* 0x76 */ { NULL, NULL, 0 },
1110 /* 0x77 */ { NULL, NULL, 0 },
1111 /* 0x78 */ { NULL, NULL, 0 },
1112 /* 0x79 */ { NULL, NULL, 0 },
1113 /* 0x7a */ { NULL, NULL, 0 },
1114 /* 0x7b */ { NULL, NULL, 0 },
1115 /* 0x7c */ { NULL, NULL, 0 },
1116 /* 0x7d */ { NULL, NULL, 0 },
1117 /* 0x7e */ { NULL, NULL, 0 },
1118 /* 0x7f */ { NULL, NULL, 0 },
1119 /* 0x80 */ { "SMBdskattr",reply_dskattr,AS_USER},
1120 /* 0x81 */ { "SMBsearch",reply_search,AS_USER},
1121 /* 0x82 */ { "SMBffirst",reply_search,AS_USER},
1122 /* 0x83 */ { "SMBfunique",reply_search,AS_USER},
1123 /* 0x84 */ { "SMBfclose",reply_fclose,AS_USER},
1124 /* 0x85 */ { NULL, NULL, 0 },
1125 /* 0x86 */ { NULL, NULL, 0 },
1126 /* 0x87 */ { NULL, NULL, 0 },
1127 /* 0x88 */ { NULL, NULL, 0 },
1128 /* 0x89 */ { NULL, NULL, 0 },
1129 /* 0x8a */ { NULL, NULL, 0 },
1130 /* 0x8b */ { NULL, NULL, 0 },
1131 /* 0x8c */ { NULL, NULL, 0 },
1132 /* 0x8d */ { NULL, NULL, 0 },
1133 /* 0x8e */ { NULL, NULL, 0 },
1134 /* 0x8f */ { NULL, NULL, 0 },
1135 /* 0x90 */ { NULL, NULL, 0 },
1136 /* 0x91 */ { NULL, NULL, 0 },
1137 /* 0x92 */ { NULL, NULL, 0 },
1138 /* 0x93 */ { NULL, NULL, 0 },
1139 /* 0x94 */ { NULL, NULL, 0 },
1140 /* 0x95 */ { NULL, NULL, 0 },
1141 /* 0x96 */ { NULL, NULL, 0 },
1142 /* 0x97 */ { NULL, NULL, 0 },
1143 /* 0x98 */ { NULL, NULL, 0 },
1144 /* 0x99 */ { NULL, NULL, 0 },
1145 /* 0x9a */ { NULL, NULL, 0 },
1146 /* 0x9b */ { NULL, NULL, 0 },
1147 /* 0x9c */ { NULL, NULL, 0 },
1148 /* 0x9d */ { NULL, NULL, 0 },
1149 /* 0x9e */ { NULL, NULL, 0 },
1150 /* 0x9f */ { NULL, NULL, 0 },
1151 /* 0xa0 */ { "SMBnttrans",reply_nttrans, AS_USER | CAN_IPC },
1152 /* 0xa1 */ { "SMBnttranss",reply_nttranss, AS_USER | CAN_IPC },
1153 /* 0xa2 */ { "SMBntcreateX",reply_ntcreate_and_X, AS_USER | CAN_IPC },
1154 /* 0xa3 */ { NULL, NULL, 0 },
1155 /* 0xa4 */ { "SMBntcancel",reply_ntcancel, 0 },
1156 /* 0xa5 */ { "SMBntrename",reply_ntrename, AS_USER | NEED_WRITE },
1157 /* 0xa6 */ { NULL, NULL, 0 },
1158 /* 0xa7 */ { NULL, NULL, 0 },
1159 /* 0xa8 */ { NULL, NULL, 0 },
1160 /* 0xa9 */ { NULL, NULL, 0 },
1161 /* 0xaa */ { NULL, NULL, 0 },
1162 /* 0xab */ { NULL, NULL, 0 },
1163 /* 0xac */ { NULL, NULL, 0 },
1164 /* 0xad */ { NULL, NULL, 0 },
1165 /* 0xae */ { NULL, NULL, 0 },
1166 /* 0xaf */ { NULL, NULL, 0 },
1167 /* 0xb0 */ { NULL, NULL, 0 },
1168 /* 0xb1 */ { NULL, NULL, 0 },
1169 /* 0xb2 */ { NULL, NULL, 0 },
1170 /* 0xb3 */ { NULL, NULL, 0 },
1171 /* 0xb4 */ { NULL, NULL, 0 },
1172 /* 0xb5 */ { NULL, NULL, 0 },
1173 /* 0xb6 */ { NULL, NULL, 0 },
1174 /* 0xb7 */ { NULL, NULL, 0 },
1175 /* 0xb8 */ { NULL, NULL, 0 },
1176 /* 0xb9 */ { NULL, NULL, 0 },
1177 /* 0xba */ { NULL, NULL, 0 },
1178 /* 0xbb */ { NULL, NULL, 0 },
1179 /* 0xbc */ { NULL, NULL, 0 },
1180 /* 0xbd */ { NULL, NULL, 0 },
1181 /* 0xbe */ { NULL, NULL, 0 },
1182 /* 0xbf */ { NULL, NULL, 0 },
1183 /* 0xc0 */ { "SMBsplopen",reply_printopen,AS_USER},
1184 /* 0xc1 */ { "SMBsplwr",reply_printwrite,AS_USER},
1185 /* 0xc2 */ { "SMBsplclose",reply_printclose,AS_USER},
1186 /* 0xc3 */ { "SMBsplretq",reply_printqueue,AS_USER},
1187 /* 0xc4 */ { NULL, NULL, 0 },
1188 /* 0xc5 */ { NULL, NULL, 0 },
1189 /* 0xc6 */ { NULL, NULL, 0 },
1190 /* 0xc7 */ { NULL, NULL, 0 },
1191 /* 0xc8 */ { NULL, NULL, 0 },
1192 /* 0xc9 */ { NULL, NULL, 0 },
1193 /* 0xca */ { NULL, NULL, 0 },
1194 /* 0xcb */ { NULL, NULL, 0 },
1195 /* 0xcc */ { NULL, NULL, 0 },
1196 /* 0xcd */ { NULL, NULL, 0 },
1197 /* 0xce */ { NULL, NULL, 0 },
1198 /* 0xcf */ { NULL, NULL, 0 },
1199 /* 0xd0 */ { "SMBsends",reply_sends,AS_GUEST},
1200 /* 0xd1 */ { "SMBsendb", NULL,AS_GUEST},
1201 /* 0xd2 */ { "SMBfwdname", NULL,AS_GUEST},
1202 /* 0xd3 */ { "SMBcancelf", NULL,AS_GUEST},
1203 /* 0xd4 */ { "SMBgetmac", NULL,AS_GUEST},
1204 /* 0xd5 */ { "SMBsendstrt",reply_sendstrt,AS_GUEST},
1205 /* 0xd6 */ { "SMBsendend",reply_sendend,AS_GUEST},
1206 /* 0xd7 */ { "SMBsendtxt",reply_sendtxt,AS_GUEST},
1207 /* 0xd8 */ { NULL, NULL, 0 },
1208 /* 0xd9 */ { NULL, NULL, 0 },
1209 /* 0xda */ { NULL, NULL, 0 },
1210 /* 0xdb */ { NULL, NULL, 0 },
1211 /* 0xdc */ { NULL, NULL, 0 },
1212 /* 0xdd */ { NULL, NULL, 0 },
1213 /* 0xde */ { NULL, NULL, 0 },
1214 /* 0xdf */ { NULL, NULL, 0 },
1215 /* 0xe0 */ { NULL, NULL, 0 },
1216 /* 0xe1 */ { NULL, NULL, 0 },
1217 /* 0xe2 */ { NULL, NULL, 0 },
1218 /* 0xe3 */ { NULL, NULL, 0 },
1219 /* 0xe4 */ { NULL, NULL, 0 },
1220 /* 0xe5 */ { NULL, NULL, 0 },
1221 /* 0xe6 */ { NULL, NULL, 0 },
1222 /* 0xe7 */ { NULL, NULL, 0 },
1223 /* 0xe8 */ { NULL, NULL, 0 },
1224 /* 0xe9 */ { NULL, NULL, 0 },
1225 /* 0xea */ { NULL, NULL, 0 },
1226 /* 0xeb */ { NULL, NULL, 0 },
1227 /* 0xec */ { NULL, NULL, 0 },
1228 /* 0xed */ { NULL, NULL, 0 },
1229 /* 0xee */ { NULL, NULL, 0 },
1230 /* 0xef */ { NULL, NULL, 0 },
1231 /* 0xf0 */ { NULL, NULL, 0 },
1232 /* 0xf1 */ { NULL, NULL, 0 },
1233 /* 0xf2 */ { NULL, NULL, 0 },
1234 /* 0xf3 */ { NULL, NULL, 0 },
1235 /* 0xf4 */ { NULL, NULL, 0 },
1236 /* 0xf5 */ { NULL, NULL, 0 },
1237 /* 0xf6 */ { NULL, NULL, 0 },
1238 /* 0xf7 */ { NULL, NULL, 0 },
1239 /* 0xf8 */ { NULL, NULL, 0 },
1240 /* 0xf9 */ { NULL, NULL, 0 },
1241 /* 0xfa */ { NULL, NULL, 0 },
1242 /* 0xfb */ { NULL, NULL, 0 },
1243 /* 0xfc */ { NULL, NULL, 0 },
1244 /* 0xfd */ { NULL, NULL, 0 },
1245 /* 0xfe */ { NULL, NULL, 0 },
1246 /* 0xff */ { NULL, NULL, 0 }
1247
1248 };
1249
1250 /*******************************************************************
1251  allocate and initialize a reply packet
1252 ********************************************************************/
1253
1254 void reply_outbuf(struct smb_request *req, uint8 num_words, uint32 num_bytes)
1255 {
1256         /*
1257          * Protect against integer wrap
1258          */
1259         if ((num_bytes > 0xffffff)
1260             || ((num_bytes + smb_size + num_words*2) > 0xffffff)) {
1261                 char *msg;
1262                 asprintf(&msg, "num_bytes too large: %u",
1263                          (unsigned)num_bytes);
1264                 smb_panic(msg);
1265         }
1266
1267         if (!(req->outbuf = TALLOC_ARRAY(
1268                       req, uint8,
1269                       smb_size + num_words*2 + num_bytes))) {
1270                 smb_panic("could not allocate output buffer\n");
1271         }
1272
1273         construct_reply_common((char *)req->inbuf, (char *)req->outbuf);
1274         srv_set_message((char *)req->outbuf, num_words, num_bytes, false);
1275         /*
1276          * Zero out the word area, the caller has to take care of the bcc area
1277          * himself
1278          */
1279         if (num_words != 0) {
1280                 memset(req->outbuf + smb_vwv0, 0, num_words*2);
1281         }
1282
1283         return;
1284 }
1285
1286
1287 /*******************************************************************
1288  Dump a packet to a file.
1289 ********************************************************************/
1290
1291 static void smb_dump(const char *name, int type, const char *data, ssize_t len)
1292 {
1293         int fd, i;
1294         char *fname = NULL;
1295         if (DEBUGLEVEL < 50) {
1296                 return;
1297         }
1298
1299         if (len < 4) len = smb_len(data)+4;
1300         for (i=1;i<100;i++) {
1301                 asprintf(&fname, "/tmp/%s.%d.%s", name, i,
1302                                 type ? "req" : "resp");
1303                 if (!fname) {
1304                         return;
1305                 }
1306                 fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0644);
1307                 if (fd != -1 || errno != EEXIST) break;
1308         }
1309         if (fd != -1) {
1310                 ssize_t ret = write(fd, data, len);
1311                 if (ret != len)
1312                         DEBUG(0,("smb_dump: problem: write returned %d\n", (int)ret ));
1313                 close(fd);
1314                 DEBUG(0,("created %s len %lu\n", fname, (unsigned long)len));
1315         }
1316         SAFE_FREE(fname);
1317 }
1318
1319 /****************************************************************************
1320  Prepare everything for calling the actual request function, and potentially
1321  call the request function via the "new" interface.
1322
1323  Return False if the "legacy" function needs to be called, everything is
1324  prepared.
1325
1326  Return True if we're done.
1327
1328  I know this API sucks, but it is the one with the least code change I could
1329  find.
1330 ****************************************************************************/
1331
1332 static connection_struct *switch_message(uint8 type, struct smb_request *req, int size)
1333 {
1334         int flags;
1335         uint16 session_tag;
1336         connection_struct *conn = NULL;
1337
1338         static uint16 last_session_tag = UID_FIELD_INVALID;
1339
1340         errno = 0;
1341
1342         /* Make sure this is an SMB packet. smb_size contains NetBIOS header
1343          * so subtract 4 from it. */
1344         if (!valid_smb_header(req->inbuf)
1345             || (size < (smb_size - 4))) {
1346                 DEBUG(2,("Non-SMB packet of length %d. Terminating server\n",
1347                          smb_len(req->inbuf)));
1348                 exit_server_cleanly("Non-SMB packet");
1349         }
1350
1351         if (smb_messages[type].fn_new == NULL) {
1352                 DEBUG(0,("Unknown message type %d!\n",type));
1353                 smb_dump("Unknown", 1, (char *)req->inbuf, size);
1354                 reply_unknown_new(req, type);
1355                 return NULL;
1356         }
1357
1358         flags = smb_messages[type].flags;
1359
1360         /* In share mode security we must ignore the vuid. */
1361         session_tag = (lp_security() == SEC_SHARE)
1362                 ? UID_FIELD_INVALID : req->vuid;
1363         conn = req->conn;
1364
1365         DEBUG(3,("switch message %s (pid %d) conn 0x%lx\n", smb_fn_name(type),
1366                  (int)sys_getpid(), (unsigned long)conn));
1367
1368         smb_dump(smb_fn_name(type), 1, (char *)req->inbuf, size);
1369
1370         /* Ensure this value is replaced in the incoming packet. */
1371         SSVAL(req->inbuf,smb_uid,session_tag);
1372
1373         /*
1374          * Ensure the correct username is in current_user_info.  This is a
1375          * really ugly bugfix for problems with multiple session_setup_and_X's
1376          * being done and allowing %U and %G substitutions to work correctly.
1377          * There is a reason this code is done here, don't move it unless you
1378          * know what you're doing... :-).
1379          * JRA.
1380          */
1381
1382         if (session_tag != last_session_tag) {
1383                 user_struct *vuser = NULL;
1384
1385                 last_session_tag = session_tag;
1386                 if(session_tag != UID_FIELD_INVALID) {
1387                         vuser = get_valid_user_struct(session_tag);
1388                         if (vuser) {
1389                                 set_current_user_info(&vuser->user);
1390                         }
1391                 }
1392         }
1393
1394         /* Does this call need to be run as the connected user? */
1395         if (flags & AS_USER) {
1396
1397                 /* Does this call need a valid tree connection? */
1398                 if (!conn) {
1399                         /*
1400                          * Amazingly, the error code depends on the command
1401                          * (from Samba4).
1402                          */
1403                         if (type == SMBntcreateX) {
1404                                 reply_nterror(req, NT_STATUS_INVALID_HANDLE);
1405                         } else {
1406                                 reply_doserror(req, ERRSRV, ERRinvnid);
1407                         }
1408                         return NULL;
1409                 }
1410
1411                 if (!change_to_user(conn,session_tag)) {
1412                         reply_nterror(req, NT_STATUS_DOS(ERRSRV, ERRbaduid));
1413                         return conn;
1414                 }
1415
1416                 /* All NEED_WRITE and CAN_IPC flags must also have AS_USER. */
1417
1418                 /* Does it need write permission? */
1419                 if ((flags & NEED_WRITE) && !CAN_WRITE(conn)) {
1420                         reply_nterror(req, NT_STATUS_MEDIA_WRITE_PROTECTED);
1421                         return conn;
1422                 }
1423
1424                 /* IPC services are limited */
1425                 if (IS_IPC(conn) && !(flags & CAN_IPC)) {
1426                         reply_doserror(req, ERRSRV,ERRaccess);
1427                         return conn;
1428                 }
1429         } else {
1430                 /* This call needs to be run as root */
1431                 change_to_root_user();
1432         }
1433
1434         /* load service specific parameters */
1435         if (conn) {
1436                 if (req->encrypted) {
1437                         conn->encrypted_tid = true;
1438                         /* encrypted required from now on. */
1439                         conn->encrypt_level = Required;
1440                 } else if (ENCRYPTION_REQUIRED(conn)) {
1441                         uint8 com = CVAL(req->inbuf,smb_com);
1442                         if (com != SMBtrans2 && com != SMBtranss2) {
1443                                 exit_server_cleanly("encryption required "
1444                                         "on connection");
1445                                 return conn;
1446                         }
1447                 }
1448
1449                 if (!set_current_service(conn,SVAL(req->inbuf,smb_flg),
1450                                          (flags & (AS_USER|DO_CHDIR)
1451                                           ?True:False))) {
1452                         reply_doserror(req, ERRSRV, ERRaccess);
1453                         return conn;
1454                 }
1455                 conn->num_smb_operations++;
1456         }
1457
1458         /* does this protocol need to be run as guest? */
1459         if ((flags & AS_GUEST)
1460             && (!change_to_guest() ||
1461                 !check_access(smbd_server_fd(), lp_hostsallow(-1),
1462                               lp_hostsdeny(-1)))) {
1463                 reply_doserror(req, ERRSRV, ERRaccess);
1464                 return conn;
1465         }
1466
1467         smb_messages[type].fn_new(req);
1468         return req->conn;
1469 }
1470
1471 /****************************************************************************
1472  Construct a reply to the incoming packet.
1473 ****************************************************************************/
1474
1475 static void construct_reply(char *inbuf, int size, size_t unread_bytes, bool encrypted)
1476 {
1477         uint8 type = CVAL(inbuf,smb_com);
1478         connection_struct *conn;
1479         struct smb_request *req;
1480
1481         chain_size = 0;
1482         file_chain_reset();
1483         reset_chain_p();
1484
1485         if (!(req = talloc(talloc_tos(), struct smb_request))) {
1486                 smb_panic("could not allocate smb_request");
1487         }
1488         init_smb_request(req, (uint8 *)inbuf, unread_bytes, encrypted);
1489
1490         conn = switch_message(type, req, size);
1491
1492         if (req->unread_bytes) {
1493                 /* writeX failed. drain socket. */
1494                 if (drain_socket(smbd_server_fd(), req->unread_bytes) !=
1495                                 req->unread_bytes) {
1496                         smb_panic("failed to drain pending bytes");
1497                 }
1498                 req->unread_bytes = 0;
1499         }
1500
1501         if (req->outbuf == NULL) {
1502                 return;
1503         }
1504
1505         if (CVAL(req->outbuf,0) == 0) {
1506                 show_msg((char *)req->outbuf);
1507         }
1508
1509         if (!srv_send_smb(smbd_server_fd(),
1510                         (char *)req->outbuf,
1511                         IS_CONN_ENCRYPTED(conn)||req->encrypted)) {
1512                 exit_server_cleanly("construct_reply: srv_send_smb failed.");
1513         }
1514
1515         TALLOC_FREE(req);
1516
1517         return;
1518 }
1519
1520 /****************************************************************************
1521  Process an smb from the client
1522 ****************************************************************************/
1523
1524 static void process_smb(char *inbuf, size_t nread, size_t unread_bytes, bool encrypted)
1525 {
1526         static int trans_num;
1527         int msg_type = CVAL(inbuf,0);
1528
1529         DO_PROFILE_INC(smb_count);
1530
1531         if (trans_num == 0) {
1532                 char addr[INET6_ADDRSTRLEN];
1533
1534                 /* on the first packet, check the global hosts allow/ hosts
1535                 deny parameters before doing any parsing of the packet
1536                 passed to us by the client.  This prevents attacks on our
1537                 parsing code from hosts not in the hosts allow list */
1538
1539                 if (!check_access(smbd_server_fd(), lp_hostsallow(-1),
1540                                   lp_hostsdeny(-1))) {
1541                         /* send a negative session response "not listening on calling name" */
1542                         static unsigned char buf[5] = {0x83, 0, 0, 1, 0x81};
1543                         DEBUG( 1, ( "Connection denied from %s\n",
1544                                 client_addr(get_client_fd(),addr,sizeof(addr)) ) );
1545                         (void)srv_send_smb(smbd_server_fd(),(char *)buf,false);
1546                         exit_server_cleanly("connection denied");
1547                 }
1548         }
1549
1550         DEBUG( 6, ( "got message type 0x%x of len 0x%x\n", msg_type,
1551                     smb_len(inbuf) ) );
1552         DEBUG( 3, ( "Transaction %d of length %d (%u toread)\n", trans_num,
1553                                 (int)nread,
1554                                 (unsigned int)unread_bytes ));
1555
1556         if (msg_type != 0) {
1557                 /*
1558                  * NetBIOS session request, keepalive, etc.
1559                  */
1560                 reply_special(inbuf);
1561                 return;
1562         }
1563
1564         show_msg(inbuf);
1565
1566         construct_reply(inbuf,nread,unread_bytes,encrypted);
1567
1568         trans_num++;
1569 }
1570
1571 /****************************************************************************
1572  Return a string containing the function name of a SMB command.
1573 ****************************************************************************/
1574
1575 const char *smb_fn_name(int type)
1576 {
1577         const char *unknown_name = "SMBunknown";
1578
1579         if (smb_messages[type].name == NULL)
1580                 return(unknown_name);
1581
1582         return(smb_messages[type].name);
1583 }
1584
1585 /****************************************************************************
1586  Helper functions for contruct_reply.
1587 ****************************************************************************/
1588
1589 static uint32 common_flags2 = FLAGS2_LONG_PATH_COMPONENTS|FLAGS2_32_BIT_ERROR_CODES;
1590
1591 void add_to_common_flags2(uint32 v)
1592 {
1593         common_flags2 |= v;
1594 }
1595
1596 void remove_from_common_flags2(uint32 v)
1597 {
1598         common_flags2 &= ~v;
1599 }
1600
1601 void construct_reply_common(const char *inbuf, char *outbuf)
1602 {
1603         srv_set_message(outbuf,0,0,false);
1604
1605         SCVAL(outbuf,smb_com,CVAL(inbuf,smb_com));
1606         SIVAL(outbuf,smb_rcls,0);
1607         SCVAL(outbuf,smb_flg, FLAG_REPLY | (CVAL(inbuf,smb_flg) & FLAG_CASELESS_PATHNAMES));
1608         SSVAL(outbuf,smb_flg2,
1609                 (SVAL(inbuf,smb_flg2) & FLAGS2_UNICODE_STRINGS) |
1610                 common_flags2);
1611         memset(outbuf+smb_pidhigh,'\0',(smb_tid-smb_pidhigh));
1612
1613         SSVAL(outbuf,smb_tid,SVAL(inbuf,smb_tid));
1614         SSVAL(outbuf,smb_pid,SVAL(inbuf,smb_pid));
1615         SSVAL(outbuf,smb_uid,SVAL(inbuf,smb_uid));
1616         SSVAL(outbuf,smb_mid,SVAL(inbuf,smb_mid));
1617 }
1618
1619 /****************************************************************************
1620  Construct a chained reply and add it to the already made reply
1621 ****************************************************************************/
1622
1623 void chain_reply(struct smb_request *req)
1624 {
1625         static char *orig_inbuf;
1626
1627         /*
1628          * Dirty little const_discard: We mess with req->inbuf, which is
1629          * declared as const. If maybe at some point this routine gets
1630          * rewritten, this const_discard could go away.
1631          */
1632         char *inbuf = CONST_DISCARD(char *, req->inbuf);
1633         int size = smb_len(req->inbuf)+4;
1634
1635         int smb_com1, smb_com2 = CVAL(inbuf,smb_vwv0);
1636         unsigned smb_off2 = SVAL(inbuf,smb_vwv1);
1637         char *inbuf2;
1638         int outsize2;
1639         int new_size;
1640         char inbuf_saved[smb_wct];
1641         char *outbuf = (char *)req->outbuf;
1642         size_t outsize = smb_len(outbuf) + 4;
1643         size_t outsize_padded;
1644         size_t ofs, to_move;
1645
1646         struct smb_request *req2;
1647         size_t caller_outputlen;
1648         char *caller_output;
1649
1650         /* Maybe its not chained, or it's an error packet. */
1651         if (smb_com2 == 0xFF || SVAL(outbuf,smb_rcls) != 0) {
1652                 SCVAL(outbuf,smb_vwv0,0xFF);
1653                 return;
1654         }
1655
1656         if (chain_size == 0) {
1657                 /* this is the first part of the chain */
1658                 orig_inbuf = inbuf;
1659         }
1660
1661         /*
1662          * We need to save the output the caller added to the chain so that we
1663          * can splice it into the final output buffer later.
1664          */
1665
1666         caller_outputlen = outsize - smb_wct;
1667
1668         caller_output = (char *)memdup(outbuf + smb_wct, caller_outputlen);
1669
1670         if (caller_output == NULL) {
1671                 /* TODO: NT_STATUS_NO_MEMORY */
1672                 smb_panic("could not dup outbuf");
1673         }
1674
1675         /*
1676          * The original Win95 redirector dies on a reply to
1677          * a lockingX and read chain unless the chain reply is
1678          * 4 byte aligned. JRA.
1679          */
1680
1681         outsize_padded = (outsize + 3) & ~3;
1682
1683         /*
1684          * remember how much the caller added to the chain, only counting
1685          * stuff after the parameter words
1686          */
1687         chain_size += outsize_padded - smb_wct;
1688
1689         /*
1690          * work out pointers into the original packets. The
1691          * headers on these need to be filled in
1692          */
1693         inbuf2 = orig_inbuf + smb_off2 + 4 - smb_wct;
1694
1695         /* remember the original command type */
1696         smb_com1 = CVAL(orig_inbuf,smb_com);
1697
1698         /* save the data which will be overwritten by the new headers */
1699         memcpy(inbuf_saved,inbuf2,smb_wct);
1700
1701         /* give the new packet the same header as the last part of the SMB */
1702         memmove(inbuf2,inbuf,smb_wct);
1703
1704         /* create the in buffer */
1705         SCVAL(inbuf2,smb_com,smb_com2);
1706
1707         /* work out the new size for the in buffer. */
1708         new_size = size - (inbuf2 - inbuf);
1709         if (new_size < 0) {
1710                 DEBUG(0,("chain_reply: chain packet size incorrect "
1711                          "(orig size = %d, offset = %d)\n",
1712                          size, (int)(inbuf2 - inbuf) ));
1713                 exit_server_cleanly("Bad chained packet");
1714                 return;
1715         }
1716
1717         /* And set it in the header. */
1718         smb_setlen(inbuf2, new_size - 4);
1719
1720         DEBUG(3,("Chained message\n"));
1721         show_msg(inbuf2);
1722
1723         if (!(req2 = talloc(talloc_tos(), struct smb_request))) {
1724                 smb_panic("could not allocate smb_request");
1725         }
1726         init_smb_request(req2, (uint8 *)inbuf2,0, req->encrypted);
1727
1728         /* process the request */
1729         switch_message(smb_com2, req2, new_size);
1730
1731         /*
1732          * We don't accept deferred operations in chained requests.
1733          */
1734         SMB_ASSERT(req2->outbuf != NULL);
1735         outsize2 = smb_len(req2->outbuf)+4;
1736
1737         /*
1738          * Move away the new command output so that caller_output fits in,
1739          * copy in the caller_output saved above.
1740          */
1741
1742         SMB_ASSERT(outsize_padded >= smb_wct);
1743
1744         /*
1745          * "ofs" is the space we need for caller_output. Equal to
1746          * caller_outputlen plus the padding.
1747          */
1748
1749         ofs = outsize_padded - smb_wct;
1750
1751         /*
1752          * "to_move" is the amount of bytes the secondary routine gave us
1753          */
1754
1755         to_move = outsize2 - smb_wct;
1756
1757         if (to_move + ofs + smb_wct + chain_size > max_send) {
1758                 smb_panic("replies too large -- would have to cut");
1759         }
1760
1761         /*
1762          * In the "new" API "outbuf" is allocated via reply_outbuf, just for
1763          * the first request in the chain. So we have to re-allocate it. In
1764          * the "old" API the only outbuf ever used is the global OutBuffer
1765          * which is always large enough.
1766          */
1767
1768         outbuf = TALLOC_REALLOC_ARRAY(NULL, outbuf, char,
1769                                       to_move + ofs + smb_wct);
1770         if (outbuf == NULL) {
1771                 smb_panic("could not realloc outbuf");
1772         }
1773
1774         req->outbuf = (uint8 *)outbuf;
1775
1776         memmove(outbuf + smb_wct + ofs, req2->outbuf + smb_wct, to_move);
1777         memcpy(outbuf + smb_wct, caller_output, caller_outputlen);
1778
1779         /*
1780          * copy the new reply header over the old one but preserve the smb_com
1781          * field
1782          */
1783         memmove(outbuf, req2->outbuf, smb_wct);
1784         SCVAL(outbuf, smb_com, smb_com1);
1785
1786         /*
1787          * We've just copied in the whole "wct" area from the secondary
1788          * function. Fix up the chaining: com2 and the offset need to be
1789          * readjusted.
1790          */
1791
1792         SCVAL(outbuf, smb_vwv0, smb_com2);
1793         SSVAL(outbuf, smb_vwv1, chain_size + smb_wct - 4);
1794
1795         if (outsize_padded > outsize) {
1796
1797                 /*
1798                  * Due to padding we have some uninitialized bytes after the
1799                  * caller's output
1800                  */
1801
1802                 memset(outbuf + outsize, 0, outsize_padded - outsize);
1803         }
1804
1805         smb_setlen(outbuf, outsize2 + chain_size - 4);
1806
1807         /*
1808          * restore the saved data, being careful not to overwrite any data
1809          * from the reply header
1810          */
1811         memcpy(inbuf2,inbuf_saved,smb_wct);
1812
1813         SAFE_FREE(caller_output);
1814         TALLOC_FREE(req2);
1815
1816         return;
1817 }
1818
1819 /****************************************************************************
1820  Setup the needed select timeout in milliseconds.
1821 ****************************************************************************/
1822
1823 static int setup_select_timeout(void)
1824 {
1825         int select_timeout;
1826
1827         select_timeout = SMBD_SELECT_TIMEOUT*1000;
1828
1829         if (print_notify_messages_pending()) {
1830                 select_timeout = MIN(select_timeout, 1000);
1831         }
1832
1833         return select_timeout;
1834 }
1835
1836 /****************************************************************************
1837  Check if services need reloading.
1838 ****************************************************************************/
1839
1840 void check_reload(time_t t)
1841 {
1842         static pid_t mypid = 0;
1843         static time_t last_smb_conf_reload_time = 0;
1844         static time_t last_printer_reload_time = 0;
1845         time_t printcap_cache_time = (time_t)lp_printcap_cache_time();
1846
1847         if(last_smb_conf_reload_time == 0) {
1848                 last_smb_conf_reload_time = t;
1849                 /* Our printing subsystem might not be ready at smbd start up.
1850                    Then no printer is available till the first printers check
1851                    is performed.  A lower initial interval circumvents this. */
1852                 if ( printcap_cache_time > 60 )
1853                         last_printer_reload_time = t - printcap_cache_time + 60;
1854                 else
1855                         last_printer_reload_time = t;
1856         }
1857
1858         if (mypid != getpid()) { /* First time or fork happened meanwhile */
1859                 /* randomize over 60 second the printcap reload to avoid all
1860                  * process hitting cupsd at the same time */
1861                 int time_range = 60;
1862
1863                 last_printer_reload_time += random() % time_range;
1864                 mypid = getpid();
1865         }
1866
1867         if (reload_after_sighup || (t >= last_smb_conf_reload_time+SMBD_RELOAD_CHECK)) {
1868                 reload_services(True);
1869                 reload_after_sighup = False;
1870                 last_smb_conf_reload_time = t;
1871         }
1872
1873         /* 'printcap cache time = 0' disable the feature */
1874
1875         if ( printcap_cache_time != 0 )
1876         {
1877                 /* see if it's time to reload or if the clock has been set back */
1878
1879                 if ( (t >= last_printer_reload_time+printcap_cache_time)
1880                         || (t-last_printer_reload_time  < 0) )
1881                 {
1882                         DEBUG( 3,( "Printcap cache time expired.\n"));
1883                         reload_printers();
1884                         last_printer_reload_time = t;
1885                 }
1886         }
1887 }
1888
1889 /****************************************************************************
1890  Process any timeout housekeeping. Return False if the caller should exit.
1891 ****************************************************************************/
1892
1893 static void timeout_processing(int *select_timeout,
1894                                time_t *last_timeout_processing_time)
1895 {
1896         time_t t;
1897
1898         *last_timeout_processing_time = t = time(NULL);
1899
1900         /* become root again if waiting */
1901         change_to_root_user();
1902
1903         /* check if we need to reload services */
1904         check_reload(t);
1905
1906         if(global_machine_password_needs_changing &&
1907                         /* for ADS we need to do a regular ADS password change, not a domain
1908                                         password change */
1909                         lp_security() == SEC_DOMAIN) {
1910
1911                 unsigned char trust_passwd_hash[16];
1912                 time_t lct;
1913                 void *lock;
1914
1915                 /*
1916                  * We're in domain level security, and the code that
1917                  * read the machine password flagged that the machine
1918                  * password needs changing.
1919                  */
1920
1921                 /*
1922                  * First, open the machine password file with an exclusive lock.
1923                  */
1924
1925                 lock = secrets_get_trust_account_lock(NULL, lp_workgroup());
1926
1927                 if (lock == NULL) {
1928                         DEBUG(0,("process: unable to lock the machine account password for \
1929 machine %s in domain %s.\n", global_myname(), lp_workgroup() ));
1930                         return;
1931                 }
1932
1933                 if(!secrets_fetch_trust_account_password(lp_workgroup(), trust_passwd_hash, &lct, NULL)) {
1934                         DEBUG(0,("process: unable to read the machine account password for \
1935 machine %s in domain %s.\n", global_myname(), lp_workgroup()));
1936                         TALLOC_FREE(lock);
1937                         return;
1938                 }
1939
1940                 /*
1941                  * Make sure someone else hasn't already done this.
1942                  */
1943
1944                 if(t < lct + lp_machine_password_timeout()) {
1945                         global_machine_password_needs_changing = False;
1946                         TALLOC_FREE(lock);
1947                         return;
1948                 }
1949
1950                 /* always just contact the PDC here */
1951
1952                 change_trust_account_password( lp_workgroup(), NULL);
1953                 global_machine_password_needs_changing = False;
1954                 TALLOC_FREE(lock);
1955         }
1956
1957         /* update printer queue caches if necessary */
1958
1959         update_monitored_printq_cache();
1960
1961         /*
1962          * Now we are root, check if the log files need pruning.
1963          * Force a log file check.
1964          */
1965         force_check_log_size();
1966         check_log_size();
1967
1968         /* Send any queued printer notify message to interested smbd's. */
1969
1970         print_notify_send_messages(smbd_messaging_context(), 0);
1971
1972         /*
1973          * Modify the select timeout depending upon
1974          * what we have remaining in our queues.
1975          */
1976
1977         *select_timeout = setup_select_timeout();
1978
1979         return;
1980 }
1981
1982 /****************************************************************************
1983  Process commands from the client
1984 ****************************************************************************/
1985
1986 void smbd_process(void)
1987 {
1988         time_t last_timeout_processing_time = time(NULL);
1989         unsigned int num_smbs = 0;
1990         size_t unread_bytes = 0;
1991
1992         max_recv = MIN(lp_maxxmit(),BUFFER_SIZE);
1993
1994         while (True) {
1995                 int select_timeout = setup_select_timeout();
1996                 int num_echos;
1997                 char *inbuf = NULL;
1998                 size_t inbuf_len = 0;
1999                 bool encrypted = false;
2000                 TALLOC_CTX *frame = talloc_stackframe_pool(8192);
2001
2002                 errno = 0;
2003
2004                 /* Did someone ask for immediate checks on things like blocking locks ? */
2005                 if (select_timeout == 0) {
2006                         timeout_processing(&select_timeout,
2007                                            &last_timeout_processing_time);
2008                         num_smbs = 0; /* Reset smb counter. */
2009                 }
2010
2011                 run_events(smbd_event_context(), 0, NULL, NULL);
2012
2013                 while (True) {
2014                         NTSTATUS status;
2015
2016                         status = receive_message_or_smb(
2017                                 talloc_tos(), &inbuf, &inbuf_len,
2018                                 select_timeout, &unread_bytes, &encrypted);
2019
2020                         if (NT_STATUS_IS_OK(status)) {
2021                                 break;
2022                         }
2023
2024                         if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT)) {
2025                                 timeout_processing(
2026                                         &select_timeout,
2027                                         &last_timeout_processing_time);
2028                                 continue;
2029                         }
2030
2031                         DEBUG(3, ("receive_message_or_smb failed: %s, "
2032                                   "exiting\n", nt_errstr(status)));
2033                         return;
2034
2035                         num_smbs = 0; /* Reset smb counter. */
2036                 }
2037
2038
2039                 /*
2040                  * Ensure we do timeout processing if the SMB we just got was
2041                  * only an echo request. This allows us to set the select
2042                  * timeout in 'receive_message_or_smb()' to any value we like
2043                  * without worrying that the client will send echo requests
2044                  * faster than the select timeout, thus starving out the
2045                  * essential processing (change notify, blocking locks) that
2046                  * the timeout code does. JRA.
2047                  */
2048                 num_echos = smb_echo_count;
2049
2050                 process_smb(inbuf, inbuf_len, unread_bytes, encrypted);
2051
2052                 TALLOC_FREE(inbuf);
2053
2054                 if (smb_echo_count != num_echos) {
2055                         timeout_processing(&select_timeout,
2056                                            &last_timeout_processing_time);
2057                         num_smbs = 0; /* Reset smb counter. */
2058                 }
2059
2060                 num_smbs++;
2061
2062                 /*
2063                  * If we are getting smb requests in a constant stream
2064                  * with no echos, make sure we attempt timeout processing
2065                  * every select_timeout milliseconds - but only check for this
2066                  * every 200 smb requests.
2067                  */
2068
2069                 if ((num_smbs % 200) == 0) {
2070                         time_t new_check_time = time(NULL);
2071                         if(new_check_time - last_timeout_processing_time >= (select_timeout/1000)) {
2072                                 timeout_processing(
2073                                         &select_timeout,
2074                                         &last_timeout_processing_time);
2075                                 num_smbs = 0; /* Reset smb counter. */
2076                                 last_timeout_processing_time = new_check_time; /* Reset time. */
2077                         }
2078                 }
2079
2080                 /* The timeout_processing function isn't run nearly
2081                    often enough to implement 'max log size' without
2082                    overrunning the size of the file by many megabytes.
2083                    This is especially true if we are running at debug
2084                    level 10.  Checking every 50 SMBs is a nice
2085                    tradeoff of performance vs log file size overrun. */
2086
2087                 if ((num_smbs % 50) == 0 && need_to_check_log_size()) {
2088                         change_to_root_user();
2089                         check_log_size();
2090                 }
2091                 TALLOC_FREE(frame);
2092         }
2093 }