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 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         /* if we get EINTR then maybe we have received an oplock
 857            signal - treat this as select returning 1. This is ugly, but
 858            is the best we can do until the oplock code knows more about
 859            signals */
 860         if (selrtn == -1 && errno == EINTR) {
 861                 async_processing(&r_fds);
 862                 /*
 863                  * After async processing we must go and do the select again, as
 864                  * the state of the flag in fds for the server file descriptor is
 865                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 866                  */
 867                 goto again;
 868         }
 869
 870         /* Check if error */
 871         if (selrtn == -1) {
 872                 /* something is wrong. Maybe the socket is dead? */
 873                 return map_nt_error_from_unix(errno);
 874         }
 875
 876         /* Did we timeout ? */
 877         if (selrtn == 0) {
 878                 return NT_STATUS_IO_TIMEOUT;
 879         }
 880
 881         /*
 882          * Ensure we process oplock break messages by preference.
 883          * This is IMPORTANT ! Otherwise we can starve other processes
 884          * sending us an oplock break message. JRA.
 885          */
 886
 887         if (oplock_message_waiting(&r_fds)) {
 888                 async_processing(&r_fds);
 889                 /*
 890                  * After async processing we must go and do the select again, as
 891                  * the state of the flag in fds for the server file descriptor is
 892                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 893                  */
 894                 goto again;
 895         }
 896
 897         status = receive_smb_talloc(mem_ctx, smbd_server_fd(), buffer, 0,
 898                                     p_unread, p_encrypted, &len);
 899
 900         if (!NT_STATUS_IS_OK(status)) {
 901                 return status;
 902         }
 903
 904         *buffer_len = len;
 905
 906         return NT_STATUS_OK;
 907 }
 908
 909 /*
 910  * Only allow 5 outstanding trans requests. We're allocating memory, so
 911  * prevent a DoS.
 912  */
 913
 914 NTSTATUS allow_new_trans(struct trans_state *list, int mid)
 915 {
 916         int count = 0;
 917         for (; list != NULL; list = list->next) {
 918
 919                 if (list->mid == mid) {
 920                         return NT_STATUS_INVALID_PARAMETER;
 921                 }
 922
 923                 count += 1;
 924         }
 925         if (count > 5) {
 926                 return NT_STATUS_INSUFFICIENT_RESOURCES;
 927         }
 928
 929         return NT_STATUS_OK;
 930 }
 931
 932 /****************************************************************************
 933  We're terminating and have closed all our files/connections etc.
 934  If there are any pending local messages we need to respond to them
 935  before termination so that other smbds don't think we just died whilst
 936  holding oplocks.
 937 ****************************************************************************/
 938
 939 void respond_to_all_remaining_local_messages(void)
 940 {
 941         /*
 942          * Assert we have no exclusive open oplocks.
 943          */
 944
 945         if(get_number_of_exclusive_open_oplocks()) {
 946                 DEBUG(0,("respond_to_all_remaining_local_messages: PANIC : we have %d exclusive oplocks.\n",
 947                         get_number_of_exclusive_open_oplocks() ));
 948                 return;
 949         }
 950
 951         process_kernel_oplocks(smbd_messaging_context(), NULL);
 952
 953         return;
 954 }
 955
 956
 957 /*
 958 These flags determine some of the permissions required to do an operation
 959
 960 Note that I don't set NEED_WRITE on some write operations because they
 961 are used by some brain-dead clients when printing, and I don't want to
 962 force write permissions on print services.
 963 */
 964 #define AS_USER (1<<0)
 965 #define NEED_WRITE (1<<1) /* Must be paired with AS_USER */
 966 #define TIME_INIT (1<<2)
 967 #define CAN_IPC (1<<3) /* Must be paired with AS_USER */
 968 #define AS_GUEST (1<<5) /* Must *NOT* be paired with AS_USER */
 969 #define DO_CHDIR (1<<6)
 970
 971 /*
 972    define a list of possible SMB messages and their corresponding
 973    functions. Any message that has a NULL function is unimplemented -
 974    please feel free to contribute implementations!
 975 */
 976 static const struct smb_message_struct {
 977         const char *name;
 978         void (*fn_new)(struct smb_request *req);
 979         int flags;
 980 } smb_messages[256] = {
 981
 982 /* 0x00 */ { "SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE},
 983 /* 0x01 */ { "SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE},
 984 /* 0x02 */ { "SMBopen",reply_open,AS_USER },
 985 /* 0x03 */ { "SMBcreate",reply_mknew,AS_USER},
 986 /* 0x04 */ { "SMBclose",reply_close,AS_USER | CAN_IPC },
 987 /* 0x05 */ { "SMBflush",reply_flush,AS_USER},
 988 /* 0x06 */ { "SMBunlink",reply_unlink,AS_USER | NEED_WRITE },
 989 /* 0x07 */ { "SMBmv",reply_mv,AS_USER | NEED_WRITE },
 990 /* 0x08 */ { "SMBgetatr",reply_getatr,AS_USER},
 991 /* 0x09 */ { "SMBsetatr",reply_setatr,AS_USER | NEED_WRITE},
 992 /* 0x0a */ { "SMBread",reply_read,AS_USER},
 993 /* 0x0b */ { "SMBwrite",reply_write,AS_USER | CAN_IPC },
 994 /* 0x0c */ { "SMBlock",reply_lock,AS_USER},
 995 /* 0x0d */ { "SMBunlock",reply_unlock,AS_USER},
 996 /* 0x0e */ { "SMBctemp",reply_ctemp,AS_USER },
 997 /* 0x0f */ { "SMBmknew",reply_mknew,AS_USER},
 998 /* 0x10 */ { "SMBcheckpath",reply_checkpath,AS_USER},
 999 /* 0x11 */ { "SMBexit",reply_exit,DO_CHDIR},
1000 /* 0x12 */ { "SMBlseek",reply_lseek,AS_USER},
1001 /* 0x13 */ { "SMBlockread",reply_lockread,AS_USER},
1002 /* 0x14 */ { "SMBwriteunlock",reply_writeunlock,AS_USER},
1003 /* 0x15 */ { NULL, NULL, 0 },
1004 /* 0x16 */ { NULL, NULL, 0 },
1005 /* 0x17 */ { NULL, NULL, 0 },
1006 /* 0x18 */ { NULL, NULL, 0 },
1007 /* 0x19 */ { NULL, NULL, 0 },
1008 /* 0x1a */ { "SMBreadbraw",reply_readbraw,AS_USER},
1009 /* 0x1b */ { "SMBreadBmpx",reply_readbmpx,AS_USER},
1010 /* 0x1c */ { "SMBreadBs",reply_readbs,AS_USER },
1011 /* 0x1d */ { "SMBwritebraw",reply_writebraw,AS_USER},
1012 /* 0x1e */ { "SMBwriteBmpx",reply_writebmpx,AS_USER},
1013 /* 0x1f */ { "SMBwriteBs",reply_writebs,AS_USER},
1014 /* 0x20 */ { "SMBwritec", NULL,0},
1015 /* 0x21 */ { NULL, NULL, 0 },
1016 /* 0x22 */ { "SMBsetattrE",reply_setattrE,AS_USER | NEED_WRITE },
1017 /* 0x23 */ { "SMBgetattrE",reply_getattrE,AS_USER },
1018 /* 0x24 */ { "SMBlockingX",reply_lockingX,AS_USER },
1019 /* 0x25 */ { "SMBtrans",reply_trans,AS_USER | CAN_IPC },
1020 /* 0x26 */ { "SMBtranss",reply_transs,AS_USER | CAN_IPC},
1021 /* 0x27 */ { "SMBioctl",reply_ioctl,0},
1022 /* 0x28 */ { "SMBioctls", NULL,AS_USER},
1023 /* 0x29 */ { "SMBcopy",reply_copy,AS_USER | NEED_WRITE },
1024 /* 0x2a */ { "SMBmove", NULL,AS_USER | NEED_WRITE },
1025 /* 0x2b */ { "SMBecho",reply_echo,0},
1026 /* 0x2c */ { "SMBwriteclose",reply_writeclose,AS_USER},
1027 /* 0x2d */ { "SMBopenX",reply_open_and_X,AS_USER | CAN_IPC },
1028 /* 0x2e */ { "SMBreadX",reply_read_and_X,AS_USER | CAN_IPC },
1029 /* 0x2f */ { "SMBwriteX",reply_write_and_X,AS_USER | CAN_IPC },
1030 /* 0x30 */ { NULL, NULL, 0 },
1031 /* 0x31 */ { NULL, NULL, 0 },
1032 /* 0x32 */ { "SMBtrans2",reply_trans2, AS_USER | CAN_IPC },
1033 /* 0x33 */ { "SMBtranss2",reply_transs2, AS_USER},
1034 /* 0x34 */ { "SMBfindclose",reply_findclose,AS_USER},
1035 /* 0x35 */ { "SMBfindnclose",reply_findnclose,AS_USER},
1036 /* 0x36 */ { NULL, NULL, 0 },
1037 /* 0x37 */ { NULL, NULL, 0 },
1038 /* 0x38 */ { NULL, NULL, 0 },
1039 /* 0x39 */ { NULL, NULL, 0 },
1040 /* 0x3a */ { NULL, NULL, 0 },
1041 /* 0x3b */ { NULL, NULL, 0 },
1042 /* 0x3c */ { NULL, NULL, 0 },
1043 /* 0x3d */ { NULL, NULL, 0 },
1044 /* 0x3e */ { NULL, NULL, 0 },
1045 /* 0x3f */ { NULL, NULL, 0 },
1046 /* 0x40 */ { NULL, NULL, 0 },
1047 /* 0x41 */ { NULL, NULL, 0 },
1048 /* 0x42 */ { NULL, NULL, 0 },
1049 /* 0x43 */ { NULL, NULL, 0 },
1050 /* 0x44 */ { NULL, NULL, 0 },
1051 /* 0x45 */ { NULL, NULL, 0 },
1052 /* 0x46 */ { NULL, NULL, 0 },
1053 /* 0x47 */ { NULL, NULL, 0 },
1054 /* 0x48 */ { NULL, NULL, 0 },
1055 /* 0x49 */ { NULL, NULL, 0 },
1056 /* 0x4a */ { NULL, NULL, 0 },
1057 /* 0x4b */ { NULL, NULL, 0 },
1058 /* 0x4c */ { NULL, NULL, 0 },
1059 /* 0x4d */ { NULL, NULL, 0 },
1060 /* 0x4e */ { NULL, NULL, 0 },
1061 /* 0x4f */ { NULL, NULL, 0 },
1062 /* 0x50 */ { NULL, NULL, 0 },
1063 /* 0x51 */ { NULL, NULL, 0 },
1064 /* 0x52 */ { NULL, NULL, 0 },
1065 /* 0x53 */ { NULL, NULL, 0 },
1066 /* 0x54 */ { NULL, NULL, 0 },
1067 /* 0x55 */ { NULL, NULL, 0 },
1068 /* 0x56 */ { NULL, NULL, 0 },
1069 /* 0x57 */ { NULL, NULL, 0 },
1070 /* 0x58 */ { NULL, NULL, 0 },
1071 /* 0x59 */ { NULL, NULL, 0 },
1072 /* 0x5a */ { NULL, NULL, 0 },
1073 /* 0x5b */ { NULL, NULL, 0 },
1074 /* 0x5c */ { NULL, NULL, 0 },
1075 /* 0x5d */ { NULL, NULL, 0 },
1076 /* 0x5e */ { NULL, NULL, 0 },
1077 /* 0x5f */ { NULL, NULL, 0 },
1078 /* 0x60 */ { NULL, NULL, 0 },
1079 /* 0x61 */ { NULL, NULL, 0 },
1080 /* 0x62 */ { NULL, NULL, 0 },
1081 /* 0x63 */ { NULL, NULL, 0 },
1082 /* 0x64 */ { NULL, NULL, 0 },
1083 /* 0x65 */ { NULL, NULL, 0 },
1084 /* 0x66 */ { NULL, NULL, 0 },
1085 /* 0x67 */ { NULL, NULL, 0 },
1086 /* 0x68 */ { NULL, NULL, 0 },
1087 /* 0x69 */ { NULL, NULL, 0 },
1088 /* 0x6a */ { NULL, NULL, 0 },
1089 /* 0x6b */ { NULL, NULL, 0 },
1090 /* 0x6c */ { NULL, NULL, 0 },
1091 /* 0x6d */ { NULL, NULL, 0 },
1092 /* 0x6e */ { NULL, NULL, 0 },
1093 /* 0x6f */ { NULL, NULL, 0 },
1094 /* 0x70 */ { "SMBtcon",reply_tcon,0},
1095 /* 0x71 */ { "SMBtdis",reply_tdis,DO_CHDIR},
1096 /* 0x72 */ { "SMBnegprot",reply_negprot,0},
1097 /* 0x73 */ { "SMBsesssetupX",reply_sesssetup_and_X,0},
1098 /* 0x74 */ { "SMBulogoffX",reply_ulogoffX, 0}, /* ulogoff doesn't give a valid TID */
1099 /* 0x75 */ { "SMBtconX",reply_tcon_and_X,0},
1100 /* 0x76 */ { NULL, NULL, 0 },
1101 /* 0x77 */ { NULL, NULL, 0 },
1102 /* 0x78 */ { NULL, NULL, 0 },
1103 /* 0x79 */ { NULL, NULL, 0 },
1104 /* 0x7a */ { NULL, NULL, 0 },
1105 /* 0x7b */ { NULL, NULL, 0 },
1106 /* 0x7c */ { NULL, NULL, 0 },
1107 /* 0x7d */ { NULL, NULL, 0 },
1108 /* 0x7e */ { NULL, NULL, 0 },
1109 /* 0x7f */ { NULL, NULL, 0 },
1110 /* 0x80 */ { "SMBdskattr",reply_dskattr,AS_USER},
1111 /* 0x81 */ { "SMBsearch",reply_search,AS_USER},
1112 /* 0x82 */ { "SMBffirst",reply_search,AS_USER},
1113 /* 0x83 */ { "SMBfunique",reply_search,AS_USER},
1114 /* 0x84 */ { "SMBfclose",reply_fclose,AS_USER},
1115 /* 0x85 */ { NULL, NULL, 0 },
1116 /* 0x86 */ { NULL, NULL, 0 },
1117 /* 0x87 */ { NULL, NULL, 0 },
1118 /* 0x88 */ { NULL, NULL, 0 },
1119 /* 0x89 */ { NULL, NULL, 0 },
1120 /* 0x8a */ { NULL, NULL, 0 },
1121 /* 0x8b */ { NULL, NULL, 0 },
1122 /* 0x8c */ { NULL, NULL, 0 },
1123 /* 0x8d */ { NULL, NULL, 0 },
1124 /* 0x8e */ { NULL, NULL, 0 },
1125 /* 0x8f */ { NULL, NULL, 0 },
1126 /* 0x90 */ { NULL, NULL, 0 },
1127 /* 0x91 */ { NULL, NULL, 0 },
1128 /* 0x92 */ { NULL, NULL, 0 },
1129 /* 0x93 */ { NULL, NULL, 0 },
1130 /* 0x94 */ { NULL, NULL, 0 },
1131 /* 0x95 */ { NULL, NULL, 0 },
1132 /* 0x96 */ { NULL, NULL, 0 },
1133 /* 0x97 */ { NULL, NULL, 0 },
1134 /* 0x98 */ { NULL, NULL, 0 },
1135 /* 0x99 */ { NULL, NULL, 0 },
1136 /* 0x9a */ { NULL, NULL, 0 },
1137 /* 0x9b */ { NULL, NULL, 0 },
1138 /* 0x9c */ { NULL, NULL, 0 },
1139 /* 0x9d */ { NULL, NULL, 0 },
1140 /* 0x9e */ { NULL, NULL, 0 },
1141 /* 0x9f */ { NULL, NULL, 0 },
1142 /* 0xa0 */ { "SMBnttrans",reply_nttrans, AS_USER | CAN_IPC },
1143 /* 0xa1 */ { "SMBnttranss",reply_nttranss, AS_USER | CAN_IPC },
1144 /* 0xa2 */ { "SMBntcreateX",reply_ntcreate_and_X, AS_USER | CAN_IPC },
1145 /* 0xa3 */ { NULL, NULL, 0 },
1146 /* 0xa4 */ { "SMBntcancel",reply_ntcancel, 0 },
1147 /* 0xa5 */ { "SMBntrename",reply_ntrename, AS_USER | NEED_WRITE },
1148 /* 0xa6 */ { NULL, NULL, 0 },
1149 /* 0xa7 */ { NULL, NULL, 0 },
1150 /* 0xa8 */ { NULL, NULL, 0 },
1151 /* 0xa9 */ { NULL, NULL, 0 },
1152 /* 0xaa */ { NULL, NULL, 0 },
1153 /* 0xab */ { NULL, NULL, 0 },
1154 /* 0xac */ { NULL, NULL, 0 },
1155 /* 0xad */ { NULL, NULL, 0 },
1156 /* 0xae */ { NULL, NULL, 0 },
1157 /* 0xaf */ { NULL, NULL, 0 },
1158 /* 0xb0 */ { NULL, NULL, 0 },
1159 /* 0xb1 */ { NULL, NULL, 0 },
1160 /* 0xb2 */ { NULL, NULL, 0 },
1161 /* 0xb3 */ { NULL, NULL, 0 },
1162 /* 0xb4 */ { NULL, NULL, 0 },
1163 /* 0xb5 */ { NULL, NULL, 0 },
1164 /* 0xb6 */ { NULL, NULL, 0 },
1165 /* 0xb7 */ { NULL, NULL, 0 },
1166 /* 0xb8 */ { NULL, NULL, 0 },
1167 /* 0xb9 */ { NULL, NULL, 0 },
1168 /* 0xba */ { NULL, NULL, 0 },
1169 /* 0xbb */ { NULL, NULL, 0 },
1170 /* 0xbc */ { NULL, NULL, 0 },
1171 /* 0xbd */ { NULL, NULL, 0 },
1172 /* 0xbe */ { NULL, NULL, 0 },
1173 /* 0xbf */ { NULL, NULL, 0 },
1174 /* 0xc0 */ { "SMBsplopen",reply_printopen,AS_USER},
1175 /* 0xc1 */ { "SMBsplwr",reply_printwrite,AS_USER},
1176 /* 0xc2 */ { "SMBsplclose",reply_printclose,AS_USER},
1177 /* 0xc3 */ { "SMBsplretq",reply_printqueue,AS_USER},
1178 /* 0xc4 */ { NULL, NULL, 0 },
1179 /* 0xc5 */ { NULL, NULL, 0 },
1180 /* 0xc6 */ { NULL, NULL, 0 },
1181 /* 0xc7 */ { NULL, NULL, 0 },
1182 /* 0xc8 */ { NULL, NULL, 0 },
1183 /* 0xc9 */ { NULL, NULL, 0 },
1184 /* 0xca */ { NULL, NULL, 0 },
1185 /* 0xcb */ { NULL, NULL, 0 },
1186 /* 0xcc */ { NULL, NULL, 0 },
1187 /* 0xcd */ { NULL, NULL, 0 },
1188 /* 0xce */ { NULL, NULL, 0 },
1189 /* 0xcf */ { NULL, NULL, 0 },
1190 /* 0xd0 */ { "SMBsends",reply_sends,AS_GUEST},
1191 /* 0xd1 */ { "SMBsendb", NULL,AS_GUEST},
1192 /* 0xd2 */ { "SMBfwdname", NULL,AS_GUEST},
1193 /* 0xd3 */ { "SMBcancelf", NULL,AS_GUEST},
1194 /* 0xd4 */ { "SMBgetmac", NULL,AS_GUEST},
1195 /* 0xd5 */ { "SMBsendstrt",reply_sendstrt,AS_GUEST},
1196 /* 0xd6 */ { "SMBsendend",reply_sendend,AS_GUEST},
1197 /* 0xd7 */ { "SMBsendtxt",reply_sendtxt,AS_GUEST},
1198 /* 0xd8 */ { NULL, NULL, 0 },
1199 /* 0xd9 */ { NULL, NULL, 0 },
1200 /* 0xda */ { NULL, NULL, 0 },
1201 /* 0xdb */ { NULL, NULL, 0 },
1202 /* 0xdc */ { NULL, NULL, 0 },
1203 /* 0xdd */ { NULL, NULL, 0 },
1204 /* 0xde */ { NULL, NULL, 0 },
1205 /* 0xdf */ { NULL, NULL, 0 },
1206 /* 0xe0 */ { NULL, NULL, 0 },
1207 /* 0xe1 */ { NULL, NULL, 0 },
1208 /* 0xe2 */ { NULL, NULL, 0 },
1209 /* 0xe3 */ { NULL, NULL, 0 },
1210 /* 0xe4 */ { NULL, NULL, 0 },
1211 /* 0xe5 */ { NULL, NULL, 0 },
1212 /* 0xe6 */ { NULL, NULL, 0 },
1213 /* 0xe7 */ { NULL, NULL, 0 },
1214 /* 0xe8 */ { NULL, NULL, 0 },
1215 /* 0xe9 */ { NULL, NULL, 0 },
1216 /* 0xea */ { NULL, NULL, 0 },
1217 /* 0xeb */ { NULL, NULL, 0 },
1218 /* 0xec */ { NULL, NULL, 0 },
1219 /* 0xed */ { NULL, NULL, 0 },
1220 /* 0xee */ { NULL, NULL, 0 },
1221 /* 0xef */ { NULL, NULL, 0 },
1222 /* 0xf0 */ { NULL, NULL, 0 },
1223 /* 0xf1 */ { NULL, NULL, 0 },
1224 /* 0xf2 */ { NULL, NULL, 0 },
1225 /* 0xf3 */ { NULL, NULL, 0 },
1226 /* 0xf4 */ { NULL, NULL, 0 },
1227 /* 0xf5 */ { NULL, NULL, 0 },
1228 /* 0xf6 */ { NULL, NULL, 0 },
1229 /* 0xf7 */ { NULL, NULL, 0 },
1230 /* 0xf8 */ { NULL, NULL, 0 },
1231 /* 0xf9 */ { NULL, NULL, 0 },
1232 /* 0xfa */ { NULL, NULL, 0 },
1233 /* 0xfb */ { NULL, NULL, 0 },
1234 /* 0xfc */ { NULL, NULL, 0 },
1235 /* 0xfd */ { NULL, NULL, 0 },
1236 /* 0xfe */ { NULL, NULL, 0 },
1237 /* 0xff */ { NULL, NULL, 0 }
1238
1239 };
1240
1241 /*******************************************************************
1242  allocate and initialize a reply packet
1243 ********************************************************************/
1244
1245 void reply_outbuf(struct smb_request *req, uint8 num_words, uint32 num_bytes)
1246 {
1247         /*
1248          * Protect against integer wrap
1249          */
1250         if ((num_bytes > 0xffffff)
1251             || ((num_bytes + smb_size + num_words*2) > 0xffffff)) {
1252                 char *msg;
1253                 asprintf(&msg, "num_bytes too large: %u",
1254                          (unsigned)num_bytes);
1255                 smb_panic(msg);
1256         }
1257
1258         if (!(req->outbuf = TALLOC_ARRAY(
1259                       req, uint8,
1260                       smb_size + num_words*2 + num_bytes))) {
1261                 smb_panic("could not allocate output buffer\n");
1262         }
1263
1264         construct_reply_common((char *)req->inbuf, (char *)req->outbuf);
1265         srv_set_message((char *)req->outbuf, num_words, num_bytes, false);
1266         /*
1267          * Zero out the word area, the caller has to take care of the bcc area
1268          * himself
1269          */
1270         if (num_words != 0) {
1271                 memset(req->outbuf + smb_vwv0, 0, num_words*2);
1272         }
1273
1274         return;
1275 }
1276
1277
1278 /*******************************************************************
1279  Dump a packet to a file.
1280 ********************************************************************/
1281
1282 static void smb_dump(const char *name, int type, const char *data, ssize_t len)
1283 {
1284         int fd, i;
1285         char *fname = NULL;
1286         if (DEBUGLEVEL < 50) {
1287                 return;
1288         }
1289
1290         if (len < 4) len = smb_len(data)+4;
1291         for (i=1;i<100;i++) {
1292                 asprintf(&fname, "/tmp/%s.%d.%s", name, i,
1293                                 type ? "req" : "resp");
1294                 if (!fname) {
1295                         return;
1296                 }
1297                 fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0644);
1298                 if (fd != -1 || errno != EEXIST) break;
1299         }
1300         if (fd != -1) {
1301                 ssize_t ret = write(fd, data, len);
1302                 if (ret != len)
1303                         DEBUG(0,("smb_dump: problem: write returned %d\n", (int)ret ));
1304                 close(fd);
1305                 DEBUG(0,("created %s len %lu\n", fname, (unsigned long)len));
1306         }
1307         SAFE_FREE(fname);
1308 }
1309
1310 /****************************************************************************
1311  Prepare everything for calling the actual request function, and potentially
1312  call the request function via the "new" interface.
1313
1314  Return False if the "legacy" function needs to be called, everything is
1315  prepared.
1316
1317  Return True if we're done.
1318
1319  I know this API sucks, but it is the one with the least code change I could
1320  find.
1321 ****************************************************************************/
1322
1323 static connection_struct *switch_message(uint8 type, struct smb_request *req, int size)
1324 {
1325         int flags;
1326         uint16 session_tag;
1327         connection_struct *conn = NULL;
1328
1329         static uint16 last_session_tag = UID_FIELD_INVALID;
1330
1331         errno = 0;
1332
1333         /* Make sure this is an SMB packet. smb_size contains NetBIOS header
1334          * so subtract 4 from it. */
1335         if (!valid_smb_header(req->inbuf)
1336             || (size < (smb_size - 4))) {
1337                 DEBUG(2,("Non-SMB packet of length %d. Terminating server\n",
1338                          smb_len(req->inbuf)));
1339                 exit_server_cleanly("Non-SMB packet");
1340         }
1341
1342         if (smb_messages[type].fn_new == NULL) {
1343                 DEBUG(0,("Unknown message type %d!\n",type));
1344                 smb_dump("Unknown", 1, (char *)req->inbuf, size);
1345                 reply_unknown_new(req, type);
1346                 return NULL;
1347         }
1348
1349         flags = smb_messages[type].flags;
1350
1351         /* In share mode security we must ignore the vuid. */
1352         session_tag = (lp_security() == SEC_SHARE)
1353                 ? UID_FIELD_INVALID : req->vuid;
1354         conn = req->conn;
1355
1356         DEBUG(3,("switch message %s (pid %d) conn 0x%lx\n", smb_fn_name(type),
1357                  (int)sys_getpid(), (unsigned long)conn));
1358
1359         smb_dump(smb_fn_name(type), 1, (char *)req->inbuf, size);
1360
1361         /* Ensure this value is replaced in the incoming packet. */
1362         SSVAL(req->inbuf,smb_uid,session_tag);
1363
1364         /*
1365          * Ensure the correct username is in current_user_info.  This is a
1366          * really ugly bugfix for problems with multiple session_setup_and_X's
1367          * being done and allowing %U and %G substitutions to work correctly.
1368          * There is a reason this code is done here, don't move it unless you
1369          * know what you're doing... :-).
1370          * JRA.
1371          */
1372
1373         if (session_tag != last_session_tag) {
1374                 user_struct *vuser = NULL;
1375
1376                 last_session_tag = session_tag;
1377                 if(session_tag != UID_FIELD_INVALID) {
1378                         vuser = get_valid_user_struct(session_tag);
1379                         if (vuser) {
1380                                 set_current_user_info(&vuser->user);
1381                         }
1382                 }
1383         }
1384
1385         /* Does this call need to be run as the connected user? */
1386         if (flags & AS_USER) {
1387
1388                 /* Does this call need a valid tree connection? */
1389                 if (!conn) {
1390                         /*
1391                          * Amazingly, the error code depends on the command
1392                          * (from Samba4).
1393                          */
1394                         if (type == SMBntcreateX) {
1395                                 reply_nterror(req, NT_STATUS_INVALID_HANDLE);
1396                         } else {
1397                                 reply_doserror(req, ERRSRV, ERRinvnid);
1398                         }
1399                         return NULL;
1400                 }
1401
1402                 if (!change_to_user(conn,session_tag)) {
1403                         reply_nterror(req, NT_STATUS_DOS(ERRSRV, ERRbaduid));
1404                         return conn;
1405                 }
1406
1407                 /* All NEED_WRITE and CAN_IPC flags must also have AS_USER. */
1408
1409                 /* Does it need write permission? */
1410                 if ((flags & NEED_WRITE) && !CAN_WRITE(conn)) {
1411                         reply_nterror(req, NT_STATUS_MEDIA_WRITE_PROTECTED);
1412                         return conn;
1413                 }
1414
1415                 /* IPC services are limited */
1416                 if (IS_IPC(conn) && !(flags & CAN_IPC)) {
1417                         reply_doserror(req, ERRSRV,ERRaccess);
1418                         return conn;
1419                 }
1420         } else {
1421                 /* This call needs to be run as root */
1422                 change_to_root_user();
1423         }
1424
1425         /* load service specific parameters */
1426         if (conn) {
1427                 if (req->encrypted) {
1428                         conn->encrypted_tid = true;
1429                         /* encrypted required from now on. */
1430                         conn->encrypt_level = Required;
1431                 } else if (ENCRYPTION_REQUIRED(conn)) {
1432                         uint8 com = CVAL(req->inbuf,smb_com);
1433                         if (com != SMBtrans2 && com != SMBtranss2) {
1434                                 exit_server_cleanly("encryption required "
1435                                         "on connection");
1436                                 return conn;
1437                         }
1438                 }
1439
1440                 if (!set_current_service(conn,SVAL(req->inbuf,smb_flg),
1441                                          (flags & (AS_USER|DO_CHDIR)
1442                                           ?True:False))) {
1443                         reply_doserror(req, ERRSRV, ERRaccess);
1444                         return conn;
1445                 }
1446                 conn->num_smb_operations++;
1447         }
1448
1449         /* does this protocol need to be run as guest? */
1450         if ((flags & AS_GUEST)
1451             && (!change_to_guest() ||
1452                 !check_access(smbd_server_fd(), lp_hostsallow(-1),
1453                               lp_hostsdeny(-1)))) {
1454                 reply_doserror(req, ERRSRV, ERRaccess);
1455                 return conn;
1456         }
1457
1458         smb_messages[type].fn_new(req);
1459         return req->conn;
1460 }
1461
1462 /****************************************************************************
1463  Construct a reply to the incoming packet.
1464 ****************************************************************************/
1465
1466 static void construct_reply(char *inbuf, int size, size_t unread_bytes, bool encrypted)
1467 {
1468         uint8 type = CVAL(inbuf,smb_com);
1469         connection_struct *conn;
1470         struct smb_request *req;
1471
1472         chain_size = 0;
1473         file_chain_reset();
1474         reset_chain_p();
1475
1476         if (!(req = talloc(talloc_tos(), struct smb_request))) {
1477                 smb_panic("could not allocate smb_request");
1478         }
1479         init_smb_request(req, (uint8 *)inbuf, unread_bytes, encrypted);
1480
1481         conn = switch_message(type, req, size);
1482
1483         if (req->unread_bytes) {
1484                 /* writeX failed. drain socket. */
1485                 if (drain_socket(smbd_server_fd(), req->unread_bytes) !=
1486                                 req->unread_bytes) {
1487                         smb_panic("failed to drain pending bytes");
1488                 }
1489                 req->unread_bytes = 0;
1490         }
1491
1492         if (req->outbuf == NULL) {
1493                 return;
1494         }
1495
1496         if (CVAL(req->outbuf,0) == 0) {
1497                 show_msg((char *)req->outbuf);
1498         }
1499
1500         if (!srv_send_smb(smbd_server_fd(),
1501                         (char *)req->outbuf,
1502                         IS_CONN_ENCRYPTED(conn)||req->encrypted)) {
1503                 exit_server_cleanly("construct_reply: srv_send_smb failed.");
1504         }
1505
1506         TALLOC_FREE(req);
1507
1508         return;
1509 }
1510
1511 /****************************************************************************
1512  Process an smb from the client
1513 ****************************************************************************/
1514
1515 static void process_smb(char *inbuf, size_t nread, size_t unread_bytes, bool encrypted)
1516 {
1517         static int trans_num;
1518         int msg_type = CVAL(inbuf,0);
1519
1520         DO_PROFILE_INC(smb_count);
1521
1522         if (trans_num == 0) {
1523                 char addr[INET6_ADDRSTRLEN];
1524
1525                 /* on the first packet, check the global hosts allow/ hosts
1526                 deny parameters before doing any parsing of the packet
1527                 passed to us by the client.  This prevents attacks on our
1528                 parsing code from hosts not in the hosts allow list */
1529
1530                 if (!check_access(smbd_server_fd(), lp_hostsallow(-1),
1531                                   lp_hostsdeny(-1))) {
1532                         /* send a negative session response "not listening on calling name" */
1533                         static unsigned char buf[5] = {0x83, 0, 0, 1, 0x81};
1534                         DEBUG( 1, ( "Connection denied from %s\n",
1535                                 client_addr(get_client_fd(),addr,sizeof(addr)) ) );
1536                         (void)srv_send_smb(smbd_server_fd(),(char *)buf,false);
1537                         exit_server_cleanly("connection denied");
1538                 }
1539         }
1540
1541         DEBUG( 6, ( "got message type 0x%x of len 0x%x\n", msg_type,
1542                     smb_len(inbuf) ) );
1543         DEBUG( 3, ( "Transaction %d of length %d (%u toread)\n", trans_num,
1544                                 (int)nread,
1545                                 (unsigned int)unread_bytes ));
1546
1547         if (msg_type != 0) {
1548                 /*
1549                  * NetBIOS session request, keepalive, etc.
1550                  */
1551                 reply_special(inbuf);
1552                 return;
1553         }
1554
1555         show_msg(inbuf);
1556
1557         construct_reply(inbuf,nread,unread_bytes,encrypted);
1558
1559         trans_num++;
1560 }
1561
1562 /****************************************************************************
1563  Return a string containing the function name of a SMB command.
1564 ****************************************************************************/
1565
1566 const char *smb_fn_name(int type)
1567 {
1568         const char *unknown_name = "SMBunknown";
1569
1570         if (smb_messages[type].name == NULL)
1571                 return(unknown_name);
1572
1573         return(smb_messages[type].name);
1574 }
1575
1576 /****************************************************************************
1577  Helper functions for contruct_reply.
1578 ****************************************************************************/
1579
1580 static uint32 common_flags2 = FLAGS2_LONG_PATH_COMPONENTS|FLAGS2_32_BIT_ERROR_CODES;
1581
1582 void add_to_common_flags2(uint32 v)
1583 {
1584         common_flags2 |= v;
1585 }
1586
1587 void remove_from_common_flags2(uint32 v)
1588 {
1589         common_flags2 &= ~v;
1590 }
1591
1592 void construct_reply_common(const char *inbuf, char *outbuf)
1593 {
1594         srv_set_message(outbuf,0,0,false);
1595
1596         SCVAL(outbuf,smb_com,CVAL(inbuf,smb_com));
1597         SIVAL(outbuf,smb_rcls,0);
1598         SCVAL(outbuf,smb_flg, FLAG_REPLY | (CVAL(inbuf,smb_flg) & FLAG_CASELESS_PATHNAMES));
1599         SSVAL(outbuf,smb_flg2,
1600                 (SVAL(inbuf,smb_flg2) & FLAGS2_UNICODE_STRINGS) |
1601                 common_flags2);
1602         memset(outbuf+smb_pidhigh,'\0',(smb_tid-smb_pidhigh));
1603
1604         SSVAL(outbuf,smb_tid,SVAL(inbuf,smb_tid));
1605         SSVAL(outbuf,smb_pid,SVAL(inbuf,smb_pid));
1606         SSVAL(outbuf,smb_uid,SVAL(inbuf,smb_uid));
1607         SSVAL(outbuf,smb_mid,SVAL(inbuf,smb_mid));
1608 }
1609
1610 /****************************************************************************
1611  Construct a chained reply and add it to the already made reply
1612 ****************************************************************************/
1613
1614 void chain_reply(struct smb_request *req)
1615 {
1616         static char *orig_inbuf;
1617
1618         /*
1619          * Dirty little const_discard: We mess with req->inbuf, which is
1620          * declared as const. If maybe at some point this routine gets
1621          * rewritten, this const_discard could go away.
1622          */
1623         char *inbuf = CONST_DISCARD(char *, req->inbuf);
1624         int size = smb_len(req->inbuf)+4;
1625
1626         int smb_com1, smb_com2 = CVAL(inbuf,smb_vwv0);
1627         unsigned smb_off2 = SVAL(inbuf,smb_vwv1);
1628         char *inbuf2;
1629         int outsize2;
1630         int new_size;
1631         char inbuf_saved[smb_wct];
1632         char *outbuf = (char *)req->outbuf;
1633         size_t outsize = smb_len(outbuf) + 4;
1634         size_t outsize_padded;
1635         size_t ofs, to_move;
1636
1637         struct smb_request *req2;
1638         size_t caller_outputlen;
1639         char *caller_output;
1640
1641         /* Maybe its not chained, or it's an error packet. */
1642         if (smb_com2 == 0xFF || SVAL(outbuf,smb_rcls) != 0) {
1643                 SCVAL(outbuf,smb_vwv0,0xFF);
1644                 return;
1645         }
1646
1647         if (chain_size == 0) {
1648                 /* this is the first part of the chain */
1649                 orig_inbuf = inbuf;
1650         }
1651
1652         /*
1653          * We need to save the output the caller added to the chain so that we
1654          * can splice it into the final output buffer later.
1655          */
1656
1657         caller_outputlen = outsize - smb_wct;
1658
1659         caller_output = (char *)memdup(outbuf + smb_wct, caller_outputlen);
1660
1661         if (caller_output == NULL) {
1662                 /* TODO: NT_STATUS_NO_MEMORY */
1663                 smb_panic("could not dup outbuf");
1664         }
1665
1666         /*
1667          * The original Win95 redirector dies on a reply to
1668          * a lockingX and read chain unless the chain reply is
1669          * 4 byte aligned. JRA.
1670          */
1671
1672         outsize_padded = (outsize + 3) & ~3;
1673
1674         /*
1675          * remember how much the caller added to the chain, only counting
1676          * stuff after the parameter words
1677          */
1678         chain_size += outsize_padded - smb_wct;
1679
1680         /*
1681          * work out pointers into the original packets. The
1682          * headers on these need to be filled in
1683          */
1684         inbuf2 = orig_inbuf + smb_off2 + 4 - smb_wct;
1685
1686         /* remember the original command type */
1687         smb_com1 = CVAL(orig_inbuf,smb_com);
1688
1689         /* save the data which will be overwritten by the new headers */
1690         memcpy(inbuf_saved,inbuf2,smb_wct);
1691
1692         /* give the new packet the same header as the last part of the SMB */
1693         memmove(inbuf2,inbuf,smb_wct);
1694
1695         /* create the in buffer */
1696         SCVAL(inbuf2,smb_com,smb_com2);
1697
1698         /* work out the new size for the in buffer. */
1699         new_size = size - (inbuf2 - inbuf);
1700         if (new_size < 0) {
1701                 DEBUG(0,("chain_reply: chain packet size incorrect "
1702                          "(orig size = %d, offset = %d)\n",
1703                          size, (int)(inbuf2 - inbuf) ));
1704                 exit_server_cleanly("Bad chained packet");
1705                 return;
1706         }
1707
1708         /* And set it in the header. */
1709         smb_setlen(inbuf2, new_size - 4);
1710
1711         DEBUG(3,("Chained message\n"));
1712         show_msg(inbuf2);
1713
1714         if (!(req2 = talloc(talloc_tos(), struct smb_request))) {
1715                 smb_panic("could not allocate smb_request");
1716         }
1717         init_smb_request(req2, (uint8 *)inbuf2,0, req->encrypted);
1718
1719         /* process the request */
1720         switch_message(smb_com2, req2, new_size);
1721
1722         /*
1723          * We don't accept deferred operations in chained requests.
1724          */
1725         SMB_ASSERT(req2->outbuf != NULL);
1726         outsize2 = smb_len(req2->outbuf)+4;
1727
1728         /*
1729          * Move away the new command output so that caller_output fits in,
1730          * copy in the caller_output saved above.
1731          */
1732
1733         SMB_ASSERT(outsize_padded >= smb_wct);
1734
1735         /*
1736          * "ofs" is the space we need for caller_output. Equal to
1737          * caller_outputlen plus the padding.
1738          */
1739
1740         ofs = outsize_padded - smb_wct;
1741
1742         /*
1743          * "to_move" is the amount of bytes the secondary routine gave us
1744          */
1745
1746         to_move = outsize2 - smb_wct;
1747
1748         if (to_move + ofs + smb_wct + chain_size > max_send) {
1749                 smb_panic("replies too large -- would have to cut");
1750         }
1751
1752         /*
1753          * In the "new" API "outbuf" is allocated via reply_outbuf, just for
1754          * the first request in the chain. So we have to re-allocate it. In
1755          * the "old" API the only outbuf ever used is the global OutBuffer
1756          * which is always large enough.
1757          */
1758
1759         outbuf = TALLOC_REALLOC_ARRAY(NULL, outbuf, char,
1760                                       to_move + ofs + smb_wct);
1761         if (outbuf == NULL) {
1762                 smb_panic("could not realloc outbuf");
1763         }
1764
1765         req->outbuf = (uint8 *)outbuf;
1766
1767         memmove(outbuf + smb_wct + ofs, req2->outbuf + smb_wct, to_move);
1768         memcpy(outbuf + smb_wct, caller_output, caller_outputlen);
1769
1770         /*
1771          * copy the new reply header over the old one but preserve the smb_com
1772          * field
1773          */
1774         memmove(outbuf, req2->outbuf, smb_wct);
1775         SCVAL(outbuf, smb_com, smb_com1);
1776
1777         /*
1778          * We've just copied in the whole "wct" area from the secondary
1779          * function. Fix up the chaining: com2 and the offset need to be
1780          * readjusted.
1781          */
1782
1783         SCVAL(outbuf, smb_vwv0, smb_com2);
1784         SSVAL(outbuf, smb_vwv1, chain_size + smb_wct - 4);
1785
1786         if (outsize_padded > outsize) {
1787
1788                 /*
1789                  * Due to padding we have some uninitialized bytes after the
1790                  * caller's output
1791                  */
1792
1793                 memset(outbuf + outsize, 0, outsize_padded - outsize);
1794         }
1795
1796         smb_setlen(outbuf, outsize2 + chain_size - 4);
1797
1798         /*
1799          * restore the saved data, being careful not to overwrite any data
1800          * from the reply header
1801          */
1802         memcpy(inbuf2,inbuf_saved,smb_wct);
1803
1804         SAFE_FREE(caller_output);
1805         TALLOC_FREE(req2);
1806
1807         return;
1808 }
1809
1810 /****************************************************************************
1811  Setup the needed select timeout in milliseconds.
1812 ****************************************************************************/
1813
1814 static int setup_select_timeout(void)
1815 {
1816         int select_timeout;
1817
1818         select_timeout = SMBD_SELECT_TIMEOUT*1000;
1819
1820         if (print_notify_messages_pending()) {
1821                 select_timeout = MIN(select_timeout, 1000);
1822         }
1823
1824         return select_timeout;
1825 }
1826
1827 /****************************************************************************
1828  Check if services need reloading.
1829 ****************************************************************************/
1830
1831 void check_reload(time_t t)
1832 {
1833         static pid_t mypid = 0;
1834         static time_t last_smb_conf_reload_time = 0;
1835         static time_t last_printer_reload_time = 0;
1836         time_t printcap_cache_time = (time_t)lp_printcap_cache_time();
1837
1838         if(last_smb_conf_reload_time == 0) {
1839                 last_smb_conf_reload_time = t;
1840                 /* Our printing subsystem might not be ready at smbd start up.
1841                    Then no printer is available till the first printers check
1842                    is performed.  A lower initial interval circumvents this. */
1843                 if ( printcap_cache_time > 60 )
1844                         last_printer_reload_time = t - printcap_cache_time + 60;
1845                 else
1846                         last_printer_reload_time = t;
1847         }
1848
1849         if (mypid != getpid()) { /* First time or fork happened meanwhile */
1850                 /* randomize over 60 second the printcap reload to avoid all
1851                  * process hitting cupsd at the same time */
1852                 int time_range = 60;
1853
1854                 last_printer_reload_time += random() % time_range;
1855                 mypid = getpid();
1856         }
1857
1858         if (reload_after_sighup || (t >= last_smb_conf_reload_time+SMBD_RELOAD_CHECK)) {
1859                 reload_services(True);
1860                 reload_after_sighup = False;
1861                 last_smb_conf_reload_time = t;
1862         }
1863
1864         /* 'printcap cache time = 0' disable the feature */
1865
1866         if ( printcap_cache_time != 0 )
1867         {
1868                 /* see if it's time to reload or if the clock has been set back */
1869
1870                 if ( (t >= last_printer_reload_time+printcap_cache_time)
1871                         || (t-last_printer_reload_time  < 0) )
1872                 {
1873                         DEBUG( 3,( "Printcap cache time expired.\n"));
1874                         reload_printers();
1875                         last_printer_reload_time = t;
1876                 }
1877         }
1878 }
1879
1880 /****************************************************************************
1881  Process any timeout housekeeping. Return False if the caller should exit.
1882 ****************************************************************************/
1883
1884 static void timeout_processing(int *select_timeout,
1885                                time_t *last_timeout_processing_time)
1886 {
1887         time_t t;
1888
1889         *last_timeout_processing_time = t = time(NULL);
1890
1891         /* become root again if waiting */
1892         change_to_root_user();
1893
1894         /* check if we need to reload services */
1895         check_reload(t);
1896
1897         if(global_machine_password_needs_changing &&
1898                         /* for ADS we need to do a regular ADS password change, not a domain
1899                                         password change */
1900                         lp_security() == SEC_DOMAIN) {
1901
1902                 unsigned char trust_passwd_hash[16];
1903                 time_t lct;
1904
1905                 /*
1906                  * We're in domain level security, and the code that
1907                  * read the machine password flagged that the machine
1908                  * password needs changing.
1909                  */
1910
1911                 /*
1912                  * First, open the machine password file with an exclusive lock.
1913                  */
1914
1915                 if (secrets_lock_trust_account_password(lp_workgroup(), True) == False) {
1916                         DEBUG(0,("process: unable to lock the machine account password for \
1917 machine %s in domain %s.\n", global_myname(), lp_workgroup() ));
1918                         return;
1919                 }
1920
1921                 if(!secrets_fetch_trust_account_password(lp_workgroup(), trust_passwd_hash, &lct, NULL)) {
1922                         DEBUG(0,("process: unable to read the machine account password for \
1923 machine %s in domain %s.\n", global_myname(), lp_workgroup()));
1924                         secrets_lock_trust_account_password(lp_workgroup(), False);
1925                         return;
1926                 }
1927
1928                 /*
1929                  * Make sure someone else hasn't already done this.
1930                  */
1931
1932                 if(t < lct + lp_machine_password_timeout()) {
1933                         global_machine_password_needs_changing = False;
1934                         secrets_lock_trust_account_password(lp_workgroup(), False);
1935                         return;
1936                 }
1937
1938                 /* always just contact the PDC here */
1939
1940                 change_trust_account_password( lp_workgroup(), NULL);
1941                 global_machine_password_needs_changing = False;
1942                 secrets_lock_trust_account_password(lp_workgroup(), False);
1943         }
1944
1945         /* update printer queue caches if necessary */
1946
1947         update_monitored_printq_cache();
1948
1949         /*
1950          * Now we are root, check if the log files need pruning.
1951          * Force a log file check.
1952          */
1953         force_check_log_size();
1954         check_log_size();
1955
1956         /* Send any queued printer notify message to interested smbd's. */
1957
1958         print_notify_send_messages(smbd_messaging_context(), 0);
1959
1960         /*
1961          * Modify the select timeout depending upon
1962          * what we have remaining in our queues.
1963          */
1964
1965         *select_timeout = setup_select_timeout();
1966
1967         return;
1968 }
1969
1970 /****************************************************************************
1971  Process commands from the client
1972 ****************************************************************************/
1973
1974 void smbd_process(void)
1975 {
1976         time_t last_timeout_processing_time = time(NULL);
1977         unsigned int num_smbs = 0;
1978         size_t unread_bytes = 0;
1979
1980         max_recv = MIN(lp_maxxmit(),BUFFER_SIZE);
1981
1982         while (True) {
1983                 int select_timeout = setup_select_timeout();
1984                 int num_echos;
1985                 char *inbuf = NULL;
1986                 size_t inbuf_len = 0;
1987                 bool encrypted = false;
1988                 TALLOC_CTX *frame = talloc_stackframe_pool(8192);
1989
1990                 errno = 0;
1991
1992                 /* Did someone ask for immediate checks on things like blocking locks ? */
1993                 if (select_timeout == 0) {
1994                         timeout_processing(&select_timeout,
1995                                            &last_timeout_processing_time);
1996                         num_smbs = 0; /* Reset smb counter. */
1997                 }
1998
1999                 run_events(smbd_event_context(), 0, NULL, NULL);
2000
2001                 while (True) {
2002                         NTSTATUS status;
2003
2004                         status = receive_message_or_smb(
2005                                 talloc_tos(), &inbuf, &inbuf_len,
2006                                 select_timeout, &unread_bytes, &encrypted);
2007
2008                         if (NT_STATUS_IS_OK(status)) {
2009                                 break;
2010                         }
2011
2012                         if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT)) {
2013                                 timeout_processing(
2014                                         &select_timeout,
2015                                         &last_timeout_processing_time);
2016                                 continue;
2017                         }
2018
2019                         DEBUG(3, ("receive_message_or_smb failed: %s, "
2020                                   "exiting\n", nt_errstr(status)));
2021                         return;
2022
2023                         num_smbs = 0; /* Reset smb counter. */
2024                 }
2025
2026
2027                 /*
2028                  * Ensure we do timeout processing if the SMB we just got was
2029                  * only an echo request. This allows us to set the select
2030                  * timeout in 'receive_message_or_smb()' to any value we like
2031                  * without worrying that the client will send echo requests
2032                  * faster than the select timeout, thus starving out the
2033                  * essential processing (change notify, blocking locks) that
2034                  * the timeout code does. JRA.
2035                  */
2036                 num_echos = smb_echo_count;
2037
2038                 process_smb(inbuf, inbuf_len, unread_bytes, encrypted);
2039
2040                 TALLOC_FREE(inbuf);
2041
2042                 if (smb_echo_count != num_echos) {
2043                         timeout_processing(&select_timeout,
2044                                            &last_timeout_processing_time);
2045                         num_smbs = 0; /* Reset smb counter. */
2046                 }
2047
2048                 num_smbs++;
2049
2050                 /*
2051                  * If we are getting smb requests in a constant stream
2052                  * with no echos, make sure we attempt timeout processing
2053                  * every select_timeout milliseconds - but only check for this
2054                  * every 200 smb requests.
2055                  */
2056
2057                 if ((num_smbs % 200) == 0) {
2058                         time_t new_check_time = time(NULL);
2059                         if(new_check_time - last_timeout_processing_time >= (select_timeout/1000)) {
2060                                 timeout_processing(
2061                                         &select_timeout,
2062                                         &last_timeout_processing_time);
2063                                 num_smbs = 0; /* Reset smb counter. */
2064                                 last_timeout_processing_time = new_check_time; /* Reset time. */
2065                         }
2066                 }
2067
2068                 /* The timeout_processing function isn't run nearly
2069                    often enough to implement 'max log size' without
2070                    overrunning the size of the file by many megabytes.
2071                    This is especially true if we are running at debug
2072                    level 10.  Checking every 50 SMBs is a nice
2073                    tradeoff of performance vs log file size overrun. */
2074
2075                 if ((num_smbs % 50) == 0 && need_to_check_log_size()) {
2076                         change_to_root_user();
2077                         check_log_size();
2078                 }
2079                 TALLOC_FREE(frame);
2080         }
2081 }