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 struct auth_context *negprot_global_auth_context;
  24 extern int smb_echo_count;
  25
  26 static enum smb_read_errors smb_read_error = SMB_READ_OK;
  27
  28 /*
  29  * Size of data we can send to client. Set
  30  *  by the client for all protocols above CORE.
  31  *  Set by us for CORE protocol.
  32  */
  33 int max_send = BUFFER_SIZE;
  34 /*
  35  * Size of the data we can receive. Set by us.
  36  * Can be modified by the max xmit parameter.
  37  */
  38 int max_recv = BUFFER_SIZE;
  39
  40 SIG_ATOMIC_T reload_after_sighup = 0;
  41 SIG_ATOMIC_T got_sig_term = 0;
  42 extern bool global_machine_password_needs_changing;
  43 extern int max_send;
  44
  45 /* Accessor function for smb_read_error for smbd functions. */
  46
  47 enum smb_read_errors *get_srv_read_error(void)
  48 {
  49         return &smb_read_error;
  50 }
  51
  52 /****************************************************************************
  53  Send an smb to a fd.
  54 ****************************************************************************/
  55
  56 bool srv_send_smb(int fd, char *buffer, bool do_encrypt)
  57 {
  58         size_t len;
  59         size_t nwritten=0;
  60         ssize_t ret;
  61         char *buf_out = buffer;
  62
  63         /* Sign the outgoing packet if required. */
  64         srv_calculate_sign_mac(buf_out);
  65
  66         if (do_encrypt) {
  67                 NTSTATUS status = srv_encrypt_buffer(buffer, &buf_out);
  68                 if (!NT_STATUS_IS_OK(status)) {
  69                         DEBUG(0, ("send_smb: SMB encryption failed "
  70                                 "on outgoing packet! Error %s\n",
  71                                 nt_errstr(status) ));
  72                         return false;
  73                 }
  74         }
  75
  76         len = smb_len(buf_out) + 4;
  77
  78         while (nwritten < len) {
  79                 ret = write_data(fd,buf_out+nwritten,len - nwritten);
  80                 if (ret <= 0) {
  81                         DEBUG(0,("Error writing %d bytes to client. %d. (%s)\n",
  82                                 (int)len,(int)ret, strerror(errno) ));
  83                         srv_free_enc_buffer(buf_out);
  84                         return false;
  85                 }
  86                 nwritten += ret;
  87         }
  88
  89         srv_free_enc_buffer(buf_out);
  90         return true;
  91 }
  92
  93 /*******************************************************************
  94  Setup the word count and byte count for a smb message.
  95 ********************************************************************/
  96
  97 int srv_set_message(char *buf,
  98                         int num_words,
  99                         int num_bytes,
 100                         bool zero)
 101 {
 102         if (zero && (num_words || num_bytes)) {
 103                 memset(buf + smb_size,'\0',num_words*2 + num_bytes);
 104         }
 105         SCVAL(buf,smb_wct,num_words);
 106         SSVAL(buf,smb_vwv + num_words*SIZEOFWORD,num_bytes);
 107         smb_setlen(buf,(smb_size + num_words*2 + num_bytes - 4));
 108         return (smb_size + num_words*2 + num_bytes);
 109 }
 110
 111 static bool valid_smb_header(const uint8_t *inbuf)
 112 {
 113         if (is_encrypted_packet(inbuf)) {
 114                 return true;
 115         }
 116         return (strncmp(smb_base(inbuf),"\377SMB",4) == 0);
 117 }
 118
 119 /* Socket functions for smbd packet processing. */
 120
 121 static bool valid_packet_size(size_t len)
 122 {
 123         /*
 124          * A WRITEX with CAP_LARGE_WRITEX can be 64k worth of data plus 65 bytes
 125          * of header. Don't print the error if this fits.... JRA.
 126          */
 127
 128         if (len > (BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE)) {
 129                 DEBUG(0,("Invalid packet length! (%lu bytes).\n",
 130                                         (unsigned long)len));
 131                 if (len > BUFFER_SIZE + (SAFETY_MARGIN/2)) {
 132
 133                         /*
 134                          * Correct fix. smb_read_error may have already been
 135                          * set. Only set it here if not already set. Global
 136                          * variables still suck :-). JRA.
 137                          */
 138
 139                         cond_set_smb_read_error(get_srv_read_error(),
 140                                                 SMB_READ_ERROR);
 141                         return false;
 142                 }
 143         }
 144         return true;
 145 }
 146
 147 static ssize_t read_packet_remainder(int fd,
 148                                         char *buffer,
 149                                         unsigned int timeout,
 150                                         ssize_t len)
 151 {
 152         ssize_t ret;
 153
 154         if(len <= 0) {
 155                 return len;
 156         }
 157
 158         ret = read_socket_with_timeout(fd, buffer, len, len, timeout,
 159                                        get_srv_read_error());
 160
 161         if (ret != len) {
 162                 cond_set_smb_read_error(get_srv_read_error(),
 163                                         SMB_READ_ERROR);
 164                 return -1;
 165         }
 166
 167         return len;
 168 }
 169
 170 /****************************************************************************
 171  Attempt a zerocopy writeX read. We know here that len > smb_size-4
 172 ****************************************************************************/
 173
 174 /*
 175  * Unfortunately, earlier versions of smbclient/libsmbclient
 176  * don't send this "standard" writeX header. I've fixed this
 177  * for 3.2 but we'll use the old method with earlier versions.
 178  * Windows and CIFSFS at least use this standard size. Not
 179  * sure about MacOSX.
 180  */
 181
 182 #define STANDARD_WRITE_AND_X_HEADER_SIZE (smb_size - 4 + /* basic header */ \
 183                                 (2*14) + /* word count (including bcc) */ \
 184                                 1 /* pad byte */)
 185
 186 static ssize_t receive_smb_raw_talloc_partial_read(TALLOC_CTX *mem_ctx,
 187                                         const char lenbuf[4],
 188                                         int fd,
 189                                         char **buffer,
 190                                         unsigned int timeout,
 191                                         size_t *p_unread)
 192 {
 193         /* Size of a WRITEX call (+4 byte len). */
 194         char writeX_header[4 + STANDARD_WRITE_AND_X_HEADER_SIZE];
 195         ssize_t len = smb_len_large(lenbuf); /* Could be a UNIX large writeX. */
 196         ssize_t toread;
 197         ssize_t ret;
 198
 199         memcpy(writeX_header, lenbuf, sizeof(lenbuf));
 200
 201         ret = read_socket_with_timeout(fd, writeX_header + 4,
 202                                        STANDARD_WRITE_AND_X_HEADER_SIZE,
 203                                        STANDARD_WRITE_AND_X_HEADER_SIZE,
 204                                        timeout, get_srv_read_error());
 205
 206         if (ret != STANDARD_WRITE_AND_X_HEADER_SIZE) {
 207                 cond_set_smb_read_error(get_srv_read_error(),
 208                                         SMB_READ_ERROR);
 209                 return -1;
 210         }
 211
 212         /*
 213          * Ok - now try and see if this is a possible
 214          * valid writeX call.
 215          */
 216
 217         if (is_valid_writeX_buffer((uint8_t *)writeX_header)) {
 218                 /*
 219                  * If the data offset is beyond what
 220                  * we've read, drain the extra bytes.
 221                  */
 222                 uint16_t doff = SVAL(writeX_header,smb_vwv11);
 223                 ssize_t newlen;
 224
 225                 if (doff > STANDARD_WRITE_AND_X_HEADER_SIZE) {
 226                         size_t drain = doff - STANDARD_WRITE_AND_X_HEADER_SIZE;
 227                         if (drain_socket(smbd_server_fd(), drain) != drain) {
 228                                 smb_panic("receive_smb_raw_talloc_partial_read:"
 229                                         " failed to drain pending bytes");
 230                         }
 231                 } else {
 232                         doff = STANDARD_WRITE_AND_X_HEADER_SIZE;
 233                 }
 234
 235                 /* Spoof down the length and null out the bcc. */
 236                 set_message_bcc(writeX_header, 0);
 237                 newlen = smb_len(writeX_header);
 238
 239                 /* Copy the header we've written. */
 240
 241                 *buffer = (char *)TALLOC_MEMDUP(mem_ctx,
 242                                 writeX_header,
 243                                 sizeof(writeX_header));
 244
 245                 if (*buffer == NULL) {
 246                         DEBUG(0, ("Could not allocate inbuf of length %d\n",
 247                                   (int)sizeof(writeX_header)));
 248                         cond_set_smb_read_error(get_srv_read_error(),
 249                                                 SMB_READ_ERROR);
 250                         return -1;
 251                 }
 252
 253                 /* Work out the remaining bytes. */
 254                 *p_unread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
 255
 256                 return newlen + 4;
 257         }
 258
 259         if (!valid_packet_size(len)) {
 260                 return -1;
 261         }
 262
 263         /*
 264          * Not a valid writeX call. Just do the standard
 265          * talloc and return.
 266          */
 267
 268         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
 269
 270         if (*buffer == NULL) {
 271                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
 272                           (int)len+4));
 273                 cond_set_smb_read_error(get_srv_read_error(),
 274                                         SMB_READ_ERROR);
 275                 return -1;
 276         }
 277
 278         /* Copy in what we already read. */
 279         memcpy(*buffer,
 280                 writeX_header,
 281                 4 + STANDARD_WRITE_AND_X_HEADER_SIZE);
 282         toread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
 283
 284         if(toread > 0) {
 285                 ret = read_packet_remainder(fd,
 286                         (*buffer) + 4 + STANDARD_WRITE_AND_X_HEADER_SIZE,
 287                                         timeout,
 288                                         toread);
 289                 if (ret != toread) {
 290                         return -1;
 291                 }
 292         }
 293
 294         return len + 4;
 295 }
 296
 297 static ssize_t receive_smb_raw_talloc(TALLOC_CTX *mem_ctx,
 298                                         int fd,
 299                                         char **buffer,
 300                                         unsigned int timeout,
 301                                         size_t *p_unread)
 302 {
 303         char lenbuf[4];
 304         ssize_t len,ret;
 305         int min_recv_size = lp_min_receive_file_size();
 306
 307         set_smb_read_error(get_srv_read_error(),SMB_READ_OK);
 308         *p_unread = 0;
 309
 310         len = read_smb_length_return_keepalive(fd, lenbuf,
 311                         timeout, get_srv_read_error());
 312         if (len < 0) {
 313                 DEBUG(10,("receive_smb_raw: length < 0!\n"));
 314
 315                 /*
 316                  * Correct fix. smb_read_error may have already been
 317                  * set. Only set it here if not already set. Global
 318                  * variables still suck :-). JRA.
 319                  */
 320
 321                 cond_set_smb_read_error(get_srv_read_error(),SMB_READ_ERROR);
 322                 return -1;
 323         }
 324
 325         if (CVAL(lenbuf,0) == 0 &&
 326                         min_recv_size &&
 327                         smb_len_large(lenbuf) > min_recv_size && /* Could be a UNIX large writeX. */
 328                         !srv_is_signing_active()) {
 329
 330                 return receive_smb_raw_talloc_partial_read(mem_ctx,
 331                                                         lenbuf,
 332                                                         fd,
 333                                                         buffer,
 334                                                         timeout,
 335                                                         p_unread);
 336         }
 337
 338         if (!valid_packet_size(len)) {
 339                 return -1;
 340         }
 341
 342         /*
 343          * The +4 here can't wrap, we've checked the length above already.
 344          */
 345
 346         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
 347
 348         if (*buffer == NULL) {
 349                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
 350                           (int)len+4));
 351                 cond_set_smb_read_error(get_srv_read_error(),SMB_READ_ERROR);
 352                 return -1;
 353         }
 354
 355         memcpy(*buffer, lenbuf, sizeof(lenbuf));
 356
 357         ret = read_packet_remainder(fd, (*buffer)+4, timeout, len);
 358         if (ret != len) {
 359                 return -1;
 360         }
 361
 362         return len + 4;
 363 }
 364
 365 static ssize_t receive_smb_talloc(TALLOC_CTX *mem_ctx,
 366                                 int fd,
 367                                 char **buffer,
 368                                 unsigned int timeout,
 369                                 size_t *p_unread,
 370                                 bool *p_encrypted)
 371 {
 372         ssize_t len;
 373
 374         *p_encrypted = false;
 375
 376         len = receive_smb_raw_talloc(mem_ctx, fd, buffer, timeout, p_unread);
 377
 378         if (len < 0) {
 379                 return -1;
 380         }
 381
 382         if (is_encrypted_packet((uint8_t *)*buffer)) {
 383                 NTSTATUS status = srv_decrypt_buffer(*buffer);
 384                 if (!NT_STATUS_IS_OK(status)) {
 385                         DEBUG(0, ("receive_smb_talloc: SMB decryption failed on "
 386                                 "incoming packet! Error %s\n",
 387                                 nt_errstr(status) ));
 388                         cond_set_smb_read_error(get_srv_read_error(),
 389                                         SMB_READ_BAD_DECRYPT);
 390                         return -1;
 391                 }
 392                 *p_encrypted = true;
 393         }
 394
 395         /* Check the incoming SMB signature. */
 396         if (!srv_check_sign_mac(*buffer, true)) {
 397                 DEBUG(0, ("receive_smb: SMB Signature verification failed on "
 398                           "incoming packet!\n"));
 399                 cond_set_smb_read_error(get_srv_read_error(),SMB_READ_BAD_SIG);
 400                 return -1;
 401         }
 402
 403         return len;
 404 }
 405
 406 /*
 407  * Initialize a struct smb_request from an inbuf
 408  */
 409
 410 void init_smb_request(struct smb_request *req,
 411                         const uint8 *inbuf,
 412                         size_t unread_bytes,
 413                         bool encrypted)
 414 {
 415         size_t req_size = smb_len(inbuf) + 4;
 416         /* Ensure we have at least smb_size bytes. */
 417         if (req_size < smb_size) {
 418                 DEBUG(0,("init_smb_request: invalid request size %u\n",
 419                         (unsigned int)req_size ));
 420                 exit_server_cleanly("Invalid SMB request");
 421         }
 422         req->flags2 = SVAL(inbuf, smb_flg2);
 423         req->smbpid = SVAL(inbuf, smb_pid);
 424         req->mid    = SVAL(inbuf, smb_mid);
 425         req->vuid   = SVAL(inbuf, smb_uid);
 426         req->tid    = SVAL(inbuf, smb_tid);
 427         req->wct    = CVAL(inbuf, smb_wct);
 428         req->unread_bytes = unread_bytes;
 429         req->encrypted = encrypted;
 430         req->conn = conn_find(req->tid);
 431
 432         /* Ensure we have at least wct words and 2 bytes of bcc. */
 433         if (smb_size + req->wct*2 > req_size) {
 434                 DEBUG(0,("init_smb_request: invalid wct number %u (size %u)\n",
 435                         (unsigned int)req->wct,
 436                         (unsigned int)req_size));
 437                 exit_server_cleanly("Invalid SMB request");
 438         }
 439         /* Ensure bcc is correct. */
 440         if (((uint8 *)smb_buf(inbuf)) + smb_buflen(inbuf) > inbuf + req_size) {
 441                 DEBUG(0,("init_smb_request: invalid bcc number %u "
 442                         "(wct = %u, size %u)\n",
 443                         (unsigned int)smb_buflen(inbuf),
 444                         (unsigned int)req->wct,
 445                         (unsigned int)req_size));
 446                 exit_server_cleanly("Invalid SMB request");
 447         }
 448         req->inbuf  = inbuf;
 449         req->outbuf = NULL;
 450 }
 451
 452 /****************************************************************************
 453  structure to hold a linked list of queued messages.
 454  for processing.
 455 ****************************************************************************/
 456
 457 static struct pending_message_list *deferred_open_queue;
 458
 459 /****************************************************************************
 460  Function to push a message onto the tail of a linked list of smb messages ready
 461  for processing.
 462 ****************************************************************************/
 463
 464 static bool push_queued_message(struct smb_request *req,
 465                                 struct timeval request_time,
 466                                 struct timeval end_time,
 467                                 char *private_data, size_t private_len)
 468 {
 469         int msg_len = smb_len(req->inbuf) + 4;
 470         struct pending_message_list *msg;
 471
 472         msg = TALLOC_ZERO_P(NULL, struct pending_message_list);
 473
 474         if(msg == NULL) {
 475                 DEBUG(0,("push_message: malloc fail (1)\n"));
 476                 return False;
 477         }
 478
 479         msg->buf = data_blob_talloc(msg, req->inbuf, msg_len);
 480         if(msg->buf.data == NULL) {
 481                 DEBUG(0,("push_message: malloc fail (2)\n"));
 482                 TALLOC_FREE(msg);
 483                 return False;
 484         }
 485
 486         msg->request_time = request_time;
 487         msg->end_time = end_time;
 488         msg->encrypted = req->encrypted;
 489
 490         if (private_data) {
 491                 msg->private_data = data_blob_talloc(msg, private_data,
 492                                                      private_len);
 493                 if (msg->private_data.data == NULL) {
 494                         DEBUG(0,("push_message: malloc fail (3)\n"));
 495                         TALLOC_FREE(msg);
 496                         return False;
 497                 }
 498         }
 499
 500         DLIST_ADD_END(deferred_open_queue, msg, struct pending_message_list *);
 501
 502         DEBUG(10,("push_message: pushed message length %u on "
 503                   "deferred_open_queue\n", (unsigned int)msg_len));
 504
 505         return True;
 506 }
 507
 508 /****************************************************************************
 509  Function to delete a sharing violation open message by mid.
 510 ****************************************************************************/
 511
 512 void remove_deferred_open_smb_message(uint16 mid)
 513 {
 514         struct pending_message_list *pml;
 515
 516         for (pml = deferred_open_queue; pml; pml = pml->next) {
 517                 if (mid == SVAL(pml->buf.data,smb_mid)) {
 518                         DEBUG(10,("remove_sharing_violation_open_smb_message: "
 519                                   "deleting mid %u len %u\n",
 520                                   (unsigned int)mid,
 521                                   (unsigned int)pml->buf.length ));
 522                         DLIST_REMOVE(deferred_open_queue, pml);
 523                         TALLOC_FREE(pml);
 524                         return;
 525                 }
 526         }
 527 }
 528
 529 /****************************************************************************
 530  Move a sharing violation open retry message to the front of the list and
 531  schedule it for immediate processing.
 532 ****************************************************************************/
 533
 534 void schedule_deferred_open_smb_message(uint16 mid)
 535 {
 536         struct pending_message_list *pml;
 537         int i = 0;
 538
 539         for (pml = deferred_open_queue; pml; pml = pml->next) {
 540                 uint16 msg_mid = SVAL(pml->buf.data,smb_mid);
 541                 DEBUG(10,("schedule_deferred_open_smb_message: [%d] msg_mid = %u\n", i++,
 542                         (unsigned int)msg_mid ));
 543                 if (mid == msg_mid) {
 544                         DEBUG(10,("schedule_deferred_open_smb_message: scheduling mid %u\n",
 545                                 mid ));
 546                         pml->end_time.tv_sec = 0;
 547                         pml->end_time.tv_usec = 0;
 548                         DLIST_PROMOTE(deferred_open_queue, pml);
 549                         return;
 550                 }
 551         }
 552
 553         DEBUG(10,("schedule_deferred_open_smb_message: failed to find message mid %u\n",
 554                 mid ));
 555 }
 556
 557 /****************************************************************************
 558  Return true if this mid is on the deferred queue.
 559 ****************************************************************************/
 560
 561 bool open_was_deferred(uint16 mid)
 562 {
 563         struct pending_message_list *pml;
 564
 565         for (pml = deferred_open_queue; pml; pml = pml->next) {
 566                 if (SVAL(pml->buf.data,smb_mid) == mid) {
 567                         return True;
 568                 }
 569         }
 570         return False;
 571 }
 572
 573 /****************************************************************************
 574  Return the message queued by this mid.
 575 ****************************************************************************/
 576
 577 struct pending_message_list *get_open_deferred_message(uint16 mid)
 578 {
 579         struct pending_message_list *pml;
 580
 581         for (pml = deferred_open_queue; pml; pml = pml->next) {
 582                 if (SVAL(pml->buf.data,smb_mid) == mid) {
 583                         return pml;
 584                 }
 585         }
 586         return NULL;
 587 }
 588
 589 /****************************************************************************
 590  Function to push a deferred open smb message onto a linked list of local smb
 591  messages ready for processing.
 592 ****************************************************************************/
 593
 594 bool push_deferred_smb_message(struct smb_request *req,
 595                                struct timeval request_time,
 596                                struct timeval timeout,
 597                                char *private_data, size_t priv_len)
 598 {
 599         struct timeval end_time;
 600
 601         if (req->unread_bytes) {
 602                 DEBUG(0,("push_deferred_smb_message: logic error ! "
 603                         "unread_bytes = %u\n",
 604                         (unsigned int)req->unread_bytes ));
 605                 smb_panic("push_deferred_smb_message: "
 606                         "logic error unread_bytes != 0" );
 607         }
 608
 609         end_time = timeval_sum(&request_time, &timeout);
 610
 611         DEBUG(10,("push_deferred_open_smb_message: pushing message len %u mid %u "
 612                   "timeout time [%u.%06u]\n",
 613                   (unsigned int) smb_len(req->inbuf)+4, (unsigned int)req->mid,
 614                   (unsigned int)end_time.tv_sec,
 615                   (unsigned int)end_time.tv_usec));
 616
 617         return push_queued_message(req, request_time, end_time,
 618                                    private_data, priv_len);
 619 }
 620
 621 struct idle_event {
 622         struct timed_event *te;
 623         struct timeval interval;
 624         char *name;
 625         bool (*handler)(const struct timeval *now, void *private_data);
 626         void *private_data;
 627 };
 628
 629 static void idle_event_handler(struct event_context *ctx,
 630                                struct timed_event *te,
 631                                const struct timeval *now,
 632                                void *private_data)
 633 {
 634         struct idle_event *event =
 635                 talloc_get_type_abort(private_data, struct idle_event);
 636
 637         TALLOC_FREE(event->te);
 638
 639         if (!event->handler(now, event->private_data)) {
 640                 /* Don't repeat, delete ourselves */
 641                 TALLOC_FREE(event);
 642                 return;
 643         }
 644
 645         event->te = event_add_timed(ctx, event,
 646                                     timeval_sum(now, &event->interval),
 647                                     event->name,
 648                                     idle_event_handler, event);
 649
 650         /* We can't do much but fail here. */
 651         SMB_ASSERT(event->te != NULL);
 652 }
 653
 654 struct idle_event *event_add_idle(struct event_context *event_ctx,
 655                                   TALLOC_CTX *mem_ctx,
 656                                   struct timeval interval,
 657                                   const char *name,
 658                                   bool (*handler)(const struct timeval *now,
 659                                                   void *private_data),
 660                                   void *private_data)
 661 {
 662         struct idle_event *result;
 663         struct timeval now = timeval_current();
 664
 665         result = TALLOC_P(mem_ctx, struct idle_event);
 666         if (result == NULL) {
 667                 DEBUG(0, ("talloc failed\n"));
 668                 return NULL;
 669         }
 670
 671         result->interval = interval;
 672         result->handler = handler;
 673         result->private_data = private_data;
 674
 675         if (!(result->name = talloc_asprintf(result, "idle_evt(%s)", name))) {
 676                 DEBUG(0, ("talloc failed\n"));
 677                 TALLOC_FREE(result);
 678                 return NULL;
 679         }
 680
 681         result->te = event_add_timed(event_ctx, result,
 682                                      timeval_sum(&now, &interval),
 683                                      result->name,
 684                                      idle_event_handler, result);
 685         if (result->te == NULL) {
 686                 DEBUG(0, ("event_add_timed failed\n"));
 687                 TALLOC_FREE(result);
 688                 return NULL;
 689         }
 690
 691         return result;
 692 }
 693
 694 /****************************************************************************
 695  Do all async processing in here. This includes kernel oplock messages, change
 696  notify events etc.
 697 ****************************************************************************/
 698
 699 static void async_processing(fd_set *pfds)
 700 {
 701         DEBUG(10,("async_processing: Doing async processing.\n"));
 702
 703         process_aio_queue();
 704
 705         process_kernel_oplocks(smbd_messaging_context(), pfds);
 706
 707         /* Do the aio check again after receive_local_message as it does a
 708            select and may have eaten our signal. */
 709         /* Is this till true? -- vl */
 710         process_aio_queue();
 711
 712         if (got_sig_term) {
 713                 exit_server_cleanly("termination signal");
 714         }
 715
 716         /* check for sighup processing */
 717         if (reload_after_sighup) {
 718                 change_to_root_user();
 719                 DEBUG(1,("Reloading services after SIGHUP\n"));
 720                 reload_services(False);
 721                 reload_after_sighup = 0;
 722         }
 723 }
 724
 725 /****************************************************************************
 726  Add a fd to the set we will be select(2)ing on.
 727 ****************************************************************************/
 728
 729 static int select_on_fd(int fd, int maxfd, fd_set *fds)
 730 {
 731         if (fd != -1) {
 732                 FD_SET(fd, fds);
 733                 maxfd = MAX(maxfd, fd);
 734         }
 735
 736         return maxfd;
 737 }
 738
 739 /****************************************************************************
 740   Do a select on an two fd's - with timeout.
 741
 742   If a local udp message has been pushed onto the
 743   queue (this can only happen during oplock break
 744   processing) call async_processing()
 745
 746   If a pending smb message has been pushed onto the
 747   queue (this can only happen during oplock break
 748   processing) return this next.
 749
 750   If the first smbfd is ready then read an smb from it.
 751   if the second (loopback UDP) fd is ready then read a message
 752   from it and setup the buffer header to identify the length
 753   and from address.
 754   Returns False on timeout or error.
 755   Else returns True.
 756
 757 The timeout is in milliseconds
 758 ****************************************************************************/
 759
 760 static bool receive_message_or_smb(TALLOC_CTX *mem_ctx,
 761                                 char **buffer,
 762                                 size_t *buffer_len,
 763                                 int timeout,
 764                                 size_t *p_unread,
 765                                 bool *p_encrypted)
 766 {
 767         fd_set r_fds, w_fds;
 768         int selrtn;
 769         struct timeval to;
 770         int maxfd = 0;
 771         ssize_t len;
 772
 773         *p_unread = 0;
 774         set_smb_read_error(get_srv_read_error(),SMB_READ_OK);
 775
 776  again:
 777
 778         if (timeout >= 0) {
 779                 to.tv_sec = timeout / 1000;
 780                 to.tv_usec = (timeout % 1000) * 1000;
 781         } else {
 782                 to.tv_sec = SMBD_SELECT_TIMEOUT;
 783                 to.tv_usec = 0;
 784         }
 785
 786         /*
 787          * Note that this call must be before processing any SMB
 788          * messages as we need to synchronously process any messages
 789          * we may have sent to ourselves from the previous SMB.
 790          */
 791         message_dispatch(smbd_messaging_context());
 792
 793         /*
 794          * Check to see if we already have a message on the deferred open queue
 795          * and it's time to schedule.
 796          */
 797         if(deferred_open_queue != NULL) {
 798                 bool pop_message = False;
 799                 struct pending_message_list *msg = deferred_open_queue;
 800
 801                 if (timeval_is_zero(&msg->end_time)) {
 802                         pop_message = True;
 803                 } else {
 804                         struct timeval tv;
 805                         SMB_BIG_INT tdif;
 806
 807                         GetTimeOfDay(&tv);
 808                         tdif = usec_time_diff(&msg->end_time, &tv);
 809                         if (tdif <= 0) {
 810                                 /* Timed out. Schedule...*/
 811                                 pop_message = True;
 812                                 DEBUG(10,("receive_message_or_smb: queued message timed out.\n"));
 813                         } else {
 814                                 /* Make a more accurate select timeout. */
 815                                 to.tv_sec = tdif / 1000000;
 816                                 to.tv_usec = tdif % 1000000;
 817                                 DEBUG(10,("receive_message_or_smb: select with timeout of [%u.%06u]\n",
 818                                         (unsigned int)to.tv_sec, (unsigned int)to.tv_usec ));
 819                         }
 820                 }
 821
 822                 if (pop_message) {
 823
 824                         *buffer = (char *)talloc_memdup(mem_ctx, msg->buf.data,
 825                                                         msg->buf.length);
 826                         if (*buffer == NULL) {
 827                                 DEBUG(0, ("talloc failed\n"));
 828                                 set_smb_read_error(get_srv_read_error(),SMB_READ_ERROR);
 829                                 return False;
 830                         }
 831                         *buffer_len = msg->buf.length;
 832                         *p_encrypted = msg->encrypted;
 833
 834                         /* We leave this message on the queue so the open code can
 835                            know this is a retry. */
 836                         DEBUG(5,("receive_message_or_smb: returning deferred open smb message.\n"));
 837                         return True;
 838                 }
 839         }
 840
 841         /*
 842          * Setup the select fd sets.
 843          */
 844
 845         FD_ZERO(&r_fds);
 846         FD_ZERO(&w_fds);
 847
 848         /*
 849          * Ensure we process oplock break messages by preference.
 850          * We have to do this before the select, after the select
 851          * and if the select returns EINTR. This is due to the fact
 852          * that the selects called from async_processing can eat an EINTR
 853          * caused by a signal (we can't take the break message there).
 854          * This is hideously complex - *MUST* be simplified for 3.0 ! JRA.
 855          */
 856
 857         if (oplock_message_waiting(&r_fds)) {
 858                 DEBUG(10,("receive_message_or_smb: oplock_message is waiting.\n"));
 859                 async_processing(&r_fds);
 860                 /*
 861                  * After async processing we must go and do the select again, as
 862                  * the state of the flag in fds for the server file descriptor is
 863                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 864                  */
 865                 goto again;
 866         }
 867
 868         /*
 869          * Are there any timed events waiting ? If so, ensure we don't
 870          * select for longer than it would take to wait for them.
 871          */
 872
 873         {
 874                 struct timeval now;
 875                 GetTimeOfDay(&now);
 876
 877                 event_add_to_select_args(smbd_event_context(), &now,
 878                                          &r_fds, &w_fds, &to, &maxfd);
 879         }
 880
 881         if (timeval_is_zero(&to)) {
 882                 /* Process a timed event now... */
 883                 if (run_events(smbd_event_context(), 0, NULL, NULL)) {
 884                         goto again;
 885                 }
 886         }
 887
 888         {
 889                 int sav;
 890                 START_PROFILE(smbd_idle);
 891
 892                 maxfd = select_on_fd(smbd_server_fd(), maxfd, &r_fds);
 893                 maxfd = select_on_fd(oplock_notify_fd(), maxfd, &r_fds);
 894
 895                 selrtn = sys_select(maxfd+1,&r_fds,&w_fds,NULL,&to);
 896                 sav = errno;
 897
 898                 END_PROFILE(smbd_idle);
 899                 errno = sav;
 900         }
 901
 902         if (run_events(smbd_event_context(), selrtn, &r_fds, &w_fds)) {
 903                 goto again;
 904         }
 905
 906         /* if we get EINTR then maybe we have received an oplock
 907            signal - treat this as select returning 1. This is ugly, but
 908            is the best we can do until the oplock code knows more about
 909            signals */
 910         if (selrtn == -1 && errno == EINTR) {
 911                 async_processing(&r_fds);
 912                 /*
 913                  * After async processing we must go and do the select again, as
 914                  * the state of the flag in fds for the server file descriptor is
 915                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 916                  */
 917                 goto again;
 918         }
 919
 920         /* Check if error */
 921         if (selrtn == -1) {
 922                 /* something is wrong. Maybe the socket is dead? */
 923                 set_smb_read_error(get_srv_read_error(),SMB_READ_ERROR);
 924                 return False;
 925         }
 926
 927         /* Did we timeout ? */
 928         if (selrtn == 0) {
 929                 set_smb_read_error(get_srv_read_error(),SMB_READ_TIMEOUT);
 930                 return False;
 931         }
 932
 933         /*
 934          * Ensure we process oplock break messages by preference.
 935          * This is IMPORTANT ! Otherwise we can starve other processes
 936          * sending us an oplock break message. JRA.
 937          */
 938
 939         if (oplock_message_waiting(&r_fds)) {
 940                 async_processing(&r_fds);
 941                 /*
 942                  * After async processing we must go and do the select again, as
 943                  * the state of the flag in fds for the server file descriptor is
 944                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 945                  */
 946                 goto again;
 947         }
 948
 949         len = receive_smb_talloc(mem_ctx, smbd_server_fd(),
 950                                 buffer, 0, p_unread, p_encrypted);
 951
 952         if (len == -1) {
 953                 return False;
 954         }
 955
 956         *buffer_len = (size_t)len;
 957
 958         return True;
 959 }
 960
 961 /*
 962  * Only allow 5 outstanding trans requests. We're allocating memory, so
 963  * prevent a DoS.
 964  */
 965
 966 NTSTATUS allow_new_trans(struct trans_state *list, int mid)
 967 {
 968         int count = 0;
 969         for (; list != NULL; list = list->next) {
 970
 971                 if (list->mid == mid) {
 972                         return NT_STATUS_INVALID_PARAMETER;
 973                 }
 974
 975                 count += 1;
 976         }
 977         if (count > 5) {
 978                 return NT_STATUS_INSUFFICIENT_RESOURCES;
 979         }
 980
 981         return NT_STATUS_OK;
 982 }
 983
 984 /****************************************************************************
 985  We're terminating and have closed all our files/connections etc.
 986  If there are any pending local messages we need to respond to them
 987  before termination so that other smbds don't think we just died whilst
 988  holding oplocks.
 989 ****************************************************************************/
 990
 991 void respond_to_all_remaining_local_messages(void)
 992 {
 993         /*
 994          * Assert we have no exclusive open oplocks.
 995          */
 996
 997         if(get_number_of_exclusive_open_oplocks()) {
 998                 DEBUG(0,("respond_to_all_remaining_local_messages: PANIC : we have %d exclusive oplocks.\n",
 999                         get_number_of_exclusive_open_oplocks() ));
1000                 return;
1001         }
1002
1003         process_kernel_oplocks(smbd_messaging_context(), NULL);
1004
1005         return;
1006 }
1007
1008
1009 /*
1010 These flags determine some of the permissions required to do an operation
1011
1012 Note that I don't set NEED_WRITE on some write operations because they
1013 are used by some brain-dead clients when printing, and I don't want to
1014 force write permissions on print services.
1015 */
1016 #define AS_USER (1<<0)
1017 #define NEED_WRITE (1<<1) /* Must be paired with AS_USER */
1018 #define TIME_INIT (1<<2)
1019 #define CAN_IPC (1<<3) /* Must be paired with AS_USER */
1020 #define AS_GUEST (1<<5) /* Must *NOT* be paired with AS_USER */
1021 #define DO_CHDIR (1<<6)
1022
1023 /*
1024    define a list of possible SMB messages and their corresponding
1025    functions. Any message that has a NULL function is unimplemented -
1026    please feel free to contribute implementations!
1027 */
1028 static const struct smb_message_struct {
1029         const char *name;
1030         void (*fn_new)(struct smb_request *req);
1031         int flags;
1032 } smb_messages[256] = {
1033
1034 /* 0x00 */ { "SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE},
1035 /* 0x01 */ { "SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE},
1036 /* 0x02 */ { "SMBopen",reply_open,AS_USER },
1037 /* 0x03 */ { "SMBcreate",reply_mknew,AS_USER},
1038 /* 0x04 */ { "SMBclose",reply_close,AS_USER | CAN_IPC },
1039 /* 0x05 */ { "SMBflush",reply_flush,AS_USER},
1040 /* 0x06 */ { "SMBunlink",reply_unlink,AS_USER | NEED_WRITE },
1041 /* 0x07 */ { "SMBmv",reply_mv,AS_USER | NEED_WRITE },
1042 /* 0x08 */ { "SMBgetatr",reply_getatr,AS_USER},
1043 /* 0x09 */ { "SMBsetatr",reply_setatr,AS_USER | NEED_WRITE},
1044 /* 0x0a */ { "SMBread",reply_read,AS_USER},
1045 /* 0x0b */ { "SMBwrite",reply_write,AS_USER | CAN_IPC },
1046 /* 0x0c */ { "SMBlock",reply_lock,AS_USER},
1047 /* 0x0d */ { "SMBunlock",reply_unlock,AS_USER},
1048 /* 0x0e */ { "SMBctemp",reply_ctemp,AS_USER },
1049 /* 0x0f */ { "SMBmknew",reply_mknew,AS_USER},
1050 /* 0x10 */ { "SMBcheckpath",reply_checkpath,AS_USER},
1051 /* 0x11 */ { "SMBexit",reply_exit,DO_CHDIR},
1052 /* 0x12 */ { "SMBlseek",reply_lseek,AS_USER},
1053 /* 0x13 */ { "SMBlockread",reply_lockread,AS_USER},
1054 /* 0x14 */ { "SMBwriteunlock",reply_writeunlock,AS_USER},
1055 /* 0x15 */ { NULL, NULL, 0 },
1056 /* 0x16 */ { NULL, NULL, 0 },
1057 /* 0x17 */ { NULL, NULL, 0 },
1058 /* 0x18 */ { NULL, NULL, 0 },
1059 /* 0x19 */ { NULL, NULL, 0 },
1060 /* 0x1a */ { "SMBreadbraw",reply_readbraw,AS_USER},
1061 /* 0x1b */ { "SMBreadBmpx",reply_readbmpx,AS_USER},
1062 /* 0x1c */ { "SMBreadBs",reply_readbs,AS_USER },
1063 /* 0x1d */ { "SMBwritebraw",reply_writebraw,AS_USER},
1064 /* 0x1e */ { "SMBwriteBmpx",reply_writebmpx,AS_USER},
1065 /* 0x1f */ { "SMBwriteBs",reply_writebs,AS_USER},
1066 /* 0x20 */ { "SMBwritec", NULL,0},
1067 /* 0x21 */ { NULL, NULL, 0 },
1068 /* 0x22 */ { "SMBsetattrE",reply_setattrE,AS_USER | NEED_WRITE },
1069 /* 0x23 */ { "SMBgetattrE",reply_getattrE,AS_USER },
1070 /* 0x24 */ { "SMBlockingX",reply_lockingX,AS_USER },
1071 /* 0x25 */ { "SMBtrans",reply_trans,AS_USER | CAN_IPC },
1072 /* 0x26 */ { "SMBtranss",reply_transs,AS_USER | CAN_IPC},
1073 /* 0x27 */ { "SMBioctl",reply_ioctl,0},
1074 /* 0x28 */ { "SMBioctls", NULL,AS_USER},
1075 /* 0x29 */ { "SMBcopy",reply_copy,AS_USER | NEED_WRITE },
1076 /* 0x2a */ { "SMBmove", NULL,AS_USER | NEED_WRITE },
1077 /* 0x2b */ { "SMBecho",reply_echo,0},
1078 /* 0x2c */ { "SMBwriteclose",reply_writeclose,AS_USER},
1079 /* 0x2d */ { "SMBopenX",reply_open_and_X,AS_USER | CAN_IPC },
1080 /* 0x2e */ { "SMBreadX",reply_read_and_X,AS_USER | CAN_IPC },
1081 /* 0x2f */ { "SMBwriteX",reply_write_and_X,AS_USER | CAN_IPC },
1082 /* 0x30 */ { NULL, NULL, 0 },
1083 /* 0x31 */ { NULL, NULL, 0 },
1084 /* 0x32 */ { "SMBtrans2",reply_trans2, AS_USER | CAN_IPC },
1085 /* 0x33 */ { "SMBtranss2",reply_transs2, AS_USER},
1086 /* 0x34 */ { "SMBfindclose",reply_findclose,AS_USER},
1087 /* 0x35 */ { "SMBfindnclose",reply_findnclose,AS_USER},
1088 /* 0x36 */ { NULL, NULL, 0 },
1089 /* 0x37 */ { NULL, NULL, 0 },
1090 /* 0x38 */ { NULL, NULL, 0 },
1091 /* 0x39 */ { NULL, NULL, 0 },
1092 /* 0x3a */ { NULL, NULL, 0 },
1093 /* 0x3b */ { NULL, NULL, 0 },
1094 /* 0x3c */ { NULL, NULL, 0 },
1095 /* 0x3d */ { NULL, NULL, 0 },
1096 /* 0x3e */ { NULL, NULL, 0 },
1097 /* 0x3f */ { NULL, NULL, 0 },
1098 /* 0x40 */ { NULL, NULL, 0 },
1099 /* 0x41 */ { NULL, NULL, 0 },
1100 /* 0x42 */ { NULL, NULL, 0 },
1101 /* 0x43 */ { NULL, NULL, 0 },
1102 /* 0x44 */ { NULL, NULL, 0 },
1103 /* 0x45 */ { NULL, NULL, 0 },
1104 /* 0x46 */ { NULL, NULL, 0 },
1105 /* 0x47 */ { NULL, NULL, 0 },
1106 /* 0x48 */ { NULL, NULL, 0 },
1107 /* 0x49 */ { NULL, NULL, 0 },
1108 /* 0x4a */ { NULL, NULL, 0 },
1109 /* 0x4b */ { NULL, NULL, 0 },
1110 /* 0x4c */ { NULL, NULL, 0 },
1111 /* 0x4d */ { NULL, NULL, 0 },
1112 /* 0x4e */ { NULL, NULL, 0 },
1113 /* 0x4f */ { NULL, NULL, 0 },
1114 /* 0x50 */ { NULL, NULL, 0 },
1115 /* 0x51 */ { NULL, NULL, 0 },
1116 /* 0x52 */ { NULL, NULL, 0 },
1117 /* 0x53 */ { NULL, NULL, 0 },
1118 /* 0x54 */ { NULL, NULL, 0 },
1119 /* 0x55 */ { NULL, NULL, 0 },
1120 /* 0x56 */ { NULL, NULL, 0 },
1121 /* 0x57 */ { NULL, NULL, 0 },
1122 /* 0x58 */ { NULL, NULL, 0 },
1123 /* 0x59 */ { NULL, NULL, 0 },
1124 /* 0x5a */ { NULL, NULL, 0 },
1125 /* 0x5b */ { NULL, NULL, 0 },
1126 /* 0x5c */ { NULL, NULL, 0 },
1127 /* 0x5d */ { NULL, NULL, 0 },
1128 /* 0x5e */ { NULL, NULL, 0 },
1129 /* 0x5f */ { NULL, NULL, 0 },
1130 /* 0x60 */ { NULL, NULL, 0 },
1131 /* 0x61 */ { NULL, NULL, 0 },
1132 /* 0x62 */ { NULL, NULL, 0 },
1133 /* 0x63 */ { NULL, NULL, 0 },
1134 /* 0x64 */ { NULL, NULL, 0 },
1135 /* 0x65 */ { NULL, NULL, 0 },
1136 /* 0x66 */ { NULL, NULL, 0 },
1137 /* 0x67 */ { NULL, NULL, 0 },
1138 /* 0x68 */ { NULL, NULL, 0 },
1139 /* 0x69 */ { NULL, NULL, 0 },
1140 /* 0x6a */ { NULL, NULL, 0 },
1141 /* 0x6b */ { NULL, NULL, 0 },
1142 /* 0x6c */ { NULL, NULL, 0 },
1143 /* 0x6d */ { NULL, NULL, 0 },
1144 /* 0x6e */ { NULL, NULL, 0 },
1145 /* 0x6f */ { NULL, NULL, 0 },
1146 /* 0x70 */ { "SMBtcon",reply_tcon,0},
1147 /* 0x71 */ { "SMBtdis",reply_tdis,DO_CHDIR},
1148 /* 0x72 */ { "SMBnegprot",reply_negprot,0},
1149 /* 0x73 */ { "SMBsesssetupX",reply_sesssetup_and_X,0},
1150 /* 0x74 */ { "SMBulogoffX",reply_ulogoffX, 0}, /* ulogoff doesn't give a valid TID */
1151 /* 0x75 */ { "SMBtconX",reply_tcon_and_X,0},
1152 /* 0x76 */ { NULL, NULL, 0 },
1153 /* 0x77 */ { NULL, NULL, 0 },
1154 /* 0x78 */ { NULL, NULL, 0 },
1155 /* 0x79 */ { NULL, NULL, 0 },
1156 /* 0x7a */ { NULL, NULL, 0 },
1157 /* 0x7b */ { NULL, NULL, 0 },
1158 /* 0x7c */ { NULL, NULL, 0 },
1159 /* 0x7d */ { NULL, NULL, 0 },
1160 /* 0x7e */ { NULL, NULL, 0 },
1161 /* 0x7f */ { NULL, NULL, 0 },
1162 /* 0x80 */ { "SMBdskattr",reply_dskattr,AS_USER},
1163 /* 0x81 */ { "SMBsearch",reply_search,AS_USER},
1164 /* 0x82 */ { "SMBffirst",reply_search,AS_USER},
1165 /* 0x83 */ { "SMBfunique",reply_search,AS_USER},
1166 /* 0x84 */ { "SMBfclose",reply_fclose,AS_USER},
1167 /* 0x85 */ { NULL, NULL, 0 },
1168 /* 0x86 */ { NULL, NULL, 0 },
1169 /* 0x87 */ { NULL, NULL, 0 },
1170 /* 0x88 */ { NULL, NULL, 0 },
1171 /* 0x89 */ { NULL, NULL, 0 },
1172 /* 0x8a */ { NULL, NULL, 0 },
1173 /* 0x8b */ { NULL, NULL, 0 },
1174 /* 0x8c */ { NULL, NULL, 0 },
1175 /* 0x8d */ { NULL, NULL, 0 },
1176 /* 0x8e */ { NULL, NULL, 0 },
1177 /* 0x8f */ { NULL, NULL, 0 },
1178 /* 0x90 */ { NULL, NULL, 0 },
1179 /* 0x91 */ { NULL, NULL, 0 },
1180 /* 0x92 */ { NULL, NULL, 0 },
1181 /* 0x93 */ { NULL, NULL, 0 },
1182 /* 0x94 */ { NULL, NULL, 0 },
1183 /* 0x95 */ { NULL, NULL, 0 },
1184 /* 0x96 */ { NULL, NULL, 0 },
1185 /* 0x97 */ { NULL, NULL, 0 },
1186 /* 0x98 */ { NULL, NULL, 0 },
1187 /* 0x99 */ { NULL, NULL, 0 },
1188 /* 0x9a */ { NULL, NULL, 0 },
1189 /* 0x9b */ { NULL, NULL, 0 },
1190 /* 0x9c */ { NULL, NULL, 0 },
1191 /* 0x9d */ { NULL, NULL, 0 },
1192 /* 0x9e */ { NULL, NULL, 0 },
1193 /* 0x9f */ { NULL, NULL, 0 },
1194 /* 0xa0 */ { "SMBnttrans",reply_nttrans, AS_USER | CAN_IPC },
1195 /* 0xa1 */ { "SMBnttranss",reply_nttranss, AS_USER | CAN_IPC },
1196 /* 0xa2 */ { "SMBntcreateX",reply_ntcreate_and_X, AS_USER | CAN_IPC },
1197 /* 0xa3 */ { NULL, NULL, 0 },
1198 /* 0xa4 */ { "SMBntcancel",reply_ntcancel, 0 },
1199 /* 0xa5 */ { "SMBntrename",reply_ntrename, AS_USER | NEED_WRITE },
1200 /* 0xa6 */ { NULL, NULL, 0 },
1201 /* 0xa7 */ { NULL, NULL, 0 },
1202 /* 0xa8 */ { NULL, NULL, 0 },
1203 /* 0xa9 */ { NULL, NULL, 0 },
1204 /* 0xaa */ { NULL, NULL, 0 },
1205 /* 0xab */ { NULL, NULL, 0 },
1206 /* 0xac */ { NULL, NULL, 0 },
1207 /* 0xad */ { NULL, NULL, 0 },
1208 /* 0xae */ { NULL, NULL, 0 },
1209 /* 0xaf */ { NULL, NULL, 0 },
1210 /* 0xb0 */ { NULL, NULL, 0 },
1211 /* 0xb1 */ { NULL, NULL, 0 },
1212 /* 0xb2 */ { NULL, NULL, 0 },
1213 /* 0xb3 */ { NULL, NULL, 0 },
1214 /* 0xb4 */ { NULL, NULL, 0 },
1215 /* 0xb5 */ { NULL, NULL, 0 },
1216 /* 0xb6 */ { NULL, NULL, 0 },
1217 /* 0xb7 */ { NULL, NULL, 0 },
1218 /* 0xb8 */ { NULL, NULL, 0 },
1219 /* 0xb9 */ { NULL, NULL, 0 },
1220 /* 0xba */ { NULL, NULL, 0 },
1221 /* 0xbb */ { NULL, NULL, 0 },
1222 /* 0xbc */ { NULL, NULL, 0 },
1223 /* 0xbd */ { NULL, NULL, 0 },
1224 /* 0xbe */ { NULL, NULL, 0 },
1225 /* 0xbf */ { NULL, NULL, 0 },
1226 /* 0xc0 */ { "SMBsplopen",reply_printopen,AS_USER},
1227 /* 0xc1 */ { "SMBsplwr",reply_printwrite,AS_USER},
1228 /* 0xc2 */ { "SMBsplclose",reply_printclose,AS_USER},
1229 /* 0xc3 */ { "SMBsplretq",reply_printqueue,AS_USER},
1230 /* 0xc4 */ { NULL, NULL, 0 },
1231 /* 0xc5 */ { NULL, NULL, 0 },
1232 /* 0xc6 */ { NULL, NULL, 0 },
1233 /* 0xc7 */ { NULL, NULL, 0 },
1234 /* 0xc8 */ { NULL, NULL, 0 },
1235 /* 0xc9 */ { NULL, NULL, 0 },
1236 /* 0xca */ { NULL, NULL, 0 },
1237 /* 0xcb */ { NULL, NULL, 0 },
1238 /* 0xcc */ { NULL, NULL, 0 },
1239 /* 0xcd */ { NULL, NULL, 0 },
1240 /* 0xce */ { NULL, NULL, 0 },
1241 /* 0xcf */ { NULL, NULL, 0 },
1242 /* 0xd0 */ { "SMBsends",reply_sends,AS_GUEST},
1243 /* 0xd1 */ { "SMBsendb", NULL,AS_GUEST},
1244 /* 0xd2 */ { "SMBfwdname", NULL,AS_GUEST},
1245 /* 0xd3 */ { "SMBcancelf", NULL,AS_GUEST},
1246 /* 0xd4 */ { "SMBgetmac", NULL,AS_GUEST},
1247 /* 0xd5 */ { "SMBsendstrt",reply_sendstrt,AS_GUEST},
1248 /* 0xd6 */ { "SMBsendend",reply_sendend,AS_GUEST},
1249 /* 0xd7 */ { "SMBsendtxt",reply_sendtxt,AS_GUEST},
1250 /* 0xd8 */ { NULL, NULL, 0 },
1251 /* 0xd9 */ { NULL, NULL, 0 },
1252 /* 0xda */ { NULL, NULL, 0 },
1253 /* 0xdb */ { NULL, NULL, 0 },
1254 /* 0xdc */ { NULL, NULL, 0 },
1255 /* 0xdd */ { NULL, NULL, 0 },
1256 /* 0xde */ { NULL, NULL, 0 },
1257 /* 0xdf */ { NULL, NULL, 0 },
1258 /* 0xe0 */ { NULL, NULL, 0 },
1259 /* 0xe1 */ { NULL, NULL, 0 },
1260 /* 0xe2 */ { NULL, NULL, 0 },
1261 /* 0xe3 */ { NULL, NULL, 0 },
1262 /* 0xe4 */ { NULL, NULL, 0 },
1263 /* 0xe5 */ { NULL, NULL, 0 },
1264 /* 0xe6 */ { NULL, NULL, 0 },
1265 /* 0xe7 */ { NULL, NULL, 0 },
1266 /* 0xe8 */ { NULL, NULL, 0 },
1267 /* 0xe9 */ { NULL, NULL, 0 },
1268 /* 0xea */ { NULL, NULL, 0 },
1269 /* 0xeb */ { NULL, NULL, 0 },
1270 /* 0xec */ { NULL, NULL, 0 },
1271 /* 0xed */ { NULL, NULL, 0 },
1272 /* 0xee */ { NULL, NULL, 0 },
1273 /* 0xef */ { NULL, NULL, 0 },
1274 /* 0xf0 */ { NULL, NULL, 0 },
1275 /* 0xf1 */ { NULL, NULL, 0 },
1276 /* 0xf2 */ { NULL, NULL, 0 },
1277 /* 0xf3 */ { NULL, NULL, 0 },
1278 /* 0xf4 */ { NULL, NULL, 0 },
1279 /* 0xf5 */ { NULL, NULL, 0 },
1280 /* 0xf6 */ { NULL, NULL, 0 },
1281 /* 0xf7 */ { NULL, NULL, 0 },
1282 /* 0xf8 */ { NULL, NULL, 0 },
1283 /* 0xf9 */ { NULL, NULL, 0 },
1284 /* 0xfa */ { NULL, NULL, 0 },
1285 /* 0xfb */ { NULL, NULL, 0 },
1286 /* 0xfc */ { NULL, NULL, 0 },
1287 /* 0xfd */ { NULL, NULL, 0 },
1288 /* 0xfe */ { NULL, NULL, 0 },
1289 /* 0xff */ { NULL, NULL, 0 }
1290
1291 };
1292
1293 /*******************************************************************
1294  allocate and initialize a reply packet
1295 ********************************************************************/
1296
1297 void reply_outbuf(struct smb_request *req, uint8 num_words, uint32 num_bytes)
1298 {
1299         /*
1300          * Protect against integer wrap
1301          */
1302         if ((num_bytes > 0xffffff)
1303             || ((num_bytes + smb_size + num_words*2) > 0xffffff)) {
1304                 char *msg;
1305                 asprintf(&msg, "num_bytes too large: %u",
1306                          (unsigned)num_bytes);
1307                 smb_panic(msg);
1308         }
1309
1310         if (!(req->outbuf = TALLOC_ARRAY(
1311                       req, uint8,
1312                       smb_size + num_words*2 + num_bytes))) {
1313                 smb_panic("could not allocate output buffer\n");
1314         }
1315
1316         construct_reply_common((char *)req->inbuf, (char *)req->outbuf);
1317         srv_set_message((char *)req->outbuf, num_words, num_bytes, false);
1318         /*
1319          * Zero out the word area, the caller has to take care of the bcc area
1320          * himself
1321          */
1322         if (num_words != 0) {
1323                 memset(req->outbuf + smb_vwv0, 0, num_words*2);
1324         }
1325
1326         return;
1327 }
1328
1329
1330 /*******************************************************************
1331  Dump a packet to a file.
1332 ********************************************************************/
1333
1334 static void smb_dump(const char *name, int type, const char *data, ssize_t len)
1335 {
1336         int fd, i;
1337         char *fname = NULL;
1338         if (DEBUGLEVEL < 50) {
1339                 return;
1340         }
1341
1342         if (len < 4) len = smb_len(data)+4;
1343         for (i=1;i<100;i++) {
1344                 asprintf(&fname, "/tmp/%s.%d.%s", name, i,
1345                                 type ? "req" : "resp");
1346                 if (!fname) {
1347                         return;
1348                 }
1349                 fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0644);
1350                 if (fd != -1 || errno != EEXIST) break;
1351         }
1352         if (fd != -1) {
1353                 ssize_t ret = write(fd, data, len);
1354                 if (ret != len)
1355                         DEBUG(0,("smb_dump: problem: write returned %d\n", (int)ret ));
1356                 close(fd);
1357                 DEBUG(0,("created %s len %lu\n", fname, (unsigned long)len));
1358         }
1359         SAFE_FREE(fname);
1360 }
1361
1362 /****************************************************************************
1363  Prepare everything for calling the actual request function, and potentially
1364  call the request function via the "new" interface.
1365
1366  Return False if the "legacy" function needs to be called, everything is
1367  prepared.
1368
1369  Return True if we're done.
1370
1371  I know this API sucks, but it is the one with the least code change I could
1372  find.
1373 ****************************************************************************/
1374
1375 static connection_struct *switch_message(uint8 type, struct smb_request *req, int size)
1376 {
1377         int flags;
1378         uint16 session_tag;
1379         connection_struct *conn = NULL;
1380
1381         static uint16 last_session_tag = UID_FIELD_INVALID;
1382
1383         errno = 0;
1384
1385         /* Make sure this is an SMB packet. smb_size contains NetBIOS header
1386          * so subtract 4 from it. */
1387         if (!valid_smb_header(req->inbuf)
1388             || (size < (smb_size - 4))) {
1389                 DEBUG(2,("Non-SMB packet of length %d. Terminating server\n",
1390                          smb_len(req->inbuf)));
1391                 exit_server_cleanly("Non-SMB packet");
1392         }
1393
1394         if (smb_messages[type].fn_new == NULL) {
1395                 DEBUG(0,("Unknown message type %d!\n",type));
1396                 smb_dump("Unknown", 1, (char *)req->inbuf, size);
1397                 reply_unknown_new(req, type);
1398                 return NULL;
1399         }
1400
1401         flags = smb_messages[type].flags;
1402
1403         /* In share mode security we must ignore the vuid. */
1404         session_tag = (lp_security() == SEC_SHARE)
1405                 ? UID_FIELD_INVALID : req->vuid;
1406         conn = req->conn;
1407
1408         DEBUG(3,("switch message %s (pid %d) conn 0x%lx\n", smb_fn_name(type),
1409                  (int)sys_getpid(), (unsigned long)conn));
1410
1411         smb_dump(smb_fn_name(type), 1, (char *)req->inbuf, size);
1412
1413         /* Ensure this value is replaced in the incoming packet. */
1414         SSVAL(req->inbuf,smb_uid,session_tag);
1415
1416         /*
1417          * Ensure the correct username is in current_user_info.  This is a
1418          * really ugly bugfix for problems with multiple session_setup_and_X's
1419          * being done and allowing %U and %G substitutions to work correctly.
1420          * There is a reason this code is done here, don't move it unless you
1421          * know what you're doing... :-).
1422          * JRA.
1423          */
1424
1425         if (session_tag != last_session_tag) {
1426                 user_struct *vuser = NULL;
1427
1428                 last_session_tag = session_tag;
1429                 if(session_tag != UID_FIELD_INVALID) {
1430                         vuser = get_valid_user_struct(session_tag);
1431                         if (vuser) {
1432                                 set_current_user_info(&vuser->user);
1433                         }
1434                 }
1435         }
1436
1437         /* Does this call need to be run as the connected user? */
1438         if (flags & AS_USER) {
1439
1440                 /* Does this call need a valid tree connection? */
1441                 if (!conn) {
1442                         /*
1443                          * Amazingly, the error code depends on the command
1444                          * (from Samba4).
1445                          */
1446                         if (type == SMBntcreateX) {
1447                                 reply_nterror(req, NT_STATUS_INVALID_HANDLE);
1448                         } else {
1449                                 reply_doserror(req, ERRSRV, ERRinvnid);
1450                         }
1451                         return NULL;
1452                 }
1453
1454                 if (!change_to_user(conn,session_tag)) {
1455                         reply_nterror(req, NT_STATUS_DOS(ERRSRV, ERRbaduid));
1456                         return conn;
1457                 }
1458
1459                 /* All NEED_WRITE and CAN_IPC flags must also have AS_USER. */
1460
1461                 /* Does it need write permission? */
1462                 if ((flags & NEED_WRITE) && !CAN_WRITE(conn)) {
1463                         reply_nterror(req, NT_STATUS_MEDIA_WRITE_PROTECTED);
1464                         return conn;
1465                 }
1466
1467                 /* IPC services are limited */
1468                 if (IS_IPC(conn) && !(flags & CAN_IPC)) {
1469                         reply_doserror(req, ERRSRV,ERRaccess);
1470                         return conn;
1471                 }
1472         } else {
1473                 /* This call needs to be run as root */
1474                 change_to_root_user();
1475         }
1476
1477         /* load service specific parameters */
1478         if (conn) {
1479                 if (req->encrypted) {
1480                         conn->encrypted_tid = true;
1481                         /* encrypted required from now on. */
1482                         conn->encrypt_level = Required;
1483                 } else if (ENCRYPTION_REQUIRED(conn)) {
1484                         uint8 com = CVAL(req->inbuf,smb_com);
1485                         if (com != SMBtrans2 && com != SMBtranss2) {
1486                                 exit_server_cleanly("encryption required "
1487                                         "on connection");
1488                                 return conn;
1489                         }
1490                 }
1491
1492                 if (!set_current_service(conn,SVAL(req->inbuf,smb_flg),
1493                                          (flags & (AS_USER|DO_CHDIR)
1494                                           ?True:False))) {
1495                         reply_doserror(req, ERRSRV, ERRaccess);
1496                         return conn;
1497                 }
1498                 conn->num_smb_operations++;
1499         }
1500
1501         /* does this protocol need to be run as guest? */
1502         if ((flags & AS_GUEST)
1503             && (!change_to_guest() ||
1504                 !check_access(smbd_server_fd(), lp_hostsallow(-1),
1505                               lp_hostsdeny(-1)))) {
1506                 reply_doserror(req, ERRSRV, ERRaccess);
1507                 return conn;
1508         }
1509
1510         smb_messages[type].fn_new(req);
1511         return req->conn;
1512 }
1513
1514 /****************************************************************************
1515  Construct a reply to the incoming packet.
1516 ****************************************************************************/
1517
1518 static void construct_reply(char *inbuf, int size, size_t unread_bytes, bool encrypted)
1519 {
1520         uint8 type = CVAL(inbuf,smb_com);
1521         connection_struct *conn;
1522         struct smb_request *req;
1523
1524         chain_size = 0;
1525         file_chain_reset();
1526         reset_chain_p();
1527
1528         if (!(req = talloc(talloc_tos(), struct smb_request))) {
1529                 smb_panic("could not allocate smb_request");
1530         }
1531         init_smb_request(req, (uint8 *)inbuf, unread_bytes, encrypted);
1532
1533         conn = switch_message(type, req, size);
1534
1535         if (req->unread_bytes) {
1536                 /* writeX failed. drain socket. */
1537                 if (drain_socket(smbd_server_fd(), req->unread_bytes) !=
1538                                 req->unread_bytes) {
1539                         smb_panic("failed to drain pending bytes");
1540                 }
1541                 req->unread_bytes = 0;
1542         }
1543
1544         if (req->outbuf == NULL) {
1545                 return;
1546         }
1547
1548         if (CVAL(req->outbuf,0) == 0) {
1549                 show_msg((char *)req->outbuf);
1550         }
1551
1552         if (!srv_send_smb(smbd_server_fd(),
1553                         (char *)req->outbuf,
1554                         IS_CONN_ENCRYPTED(conn)||req->encrypted)) {
1555                 exit_server_cleanly("construct_reply: srv_send_smb failed.");
1556         }
1557
1558         TALLOC_FREE(req);
1559
1560         return;
1561 }
1562
1563 /****************************************************************************
1564  Process an smb from the client
1565 ****************************************************************************/
1566
1567 static void process_smb(char *inbuf, size_t nread, size_t unread_bytes, bool encrypted)
1568 {
1569         static int trans_num;
1570         int msg_type = CVAL(inbuf,0);
1571
1572         DO_PROFILE_INC(smb_count);
1573
1574         if (trans_num == 0) {
1575                 char addr[INET6_ADDRSTRLEN];
1576
1577                 /* on the first packet, check the global hosts allow/ hosts
1578                 deny parameters before doing any parsing of the packet
1579                 passed to us by the client.  This prevents attacks on our
1580                 parsing code from hosts not in the hosts allow list */
1581
1582                 if (!check_access(smbd_server_fd(), lp_hostsallow(-1),
1583                                   lp_hostsdeny(-1))) {
1584                         /* send a negative session response "not listening on calling name" */
1585                         static unsigned char buf[5] = {0x83, 0, 0, 1, 0x81};
1586                         DEBUG( 1, ( "Connection denied from %s\n",
1587                                 client_addr(get_client_fd(),addr,sizeof(addr)) ) );
1588                         (void)srv_send_smb(smbd_server_fd(),(char *)buf,false);
1589                         exit_server_cleanly("connection denied");
1590                 }
1591         }
1592
1593         DEBUG( 6, ( "got message type 0x%x of len 0x%x\n", msg_type,
1594                     smb_len(inbuf) ) );
1595         DEBUG( 3, ( "Transaction %d of length %d (%u toread)\n", trans_num,
1596                                 (int)nread,
1597                                 (unsigned int)unread_bytes ));
1598
1599         if (msg_type != 0) {
1600                 /*
1601                  * NetBIOS session request, keepalive, etc.
1602                  */
1603                 reply_special(inbuf);
1604                 return;
1605         }
1606
1607         show_msg(inbuf);
1608
1609         construct_reply(inbuf,nread,unread_bytes,encrypted);
1610
1611         trans_num++;
1612 }
1613
1614 /****************************************************************************
1615  Return a string containing the function name of a SMB command.
1616 ****************************************************************************/
1617
1618 const char *smb_fn_name(int type)
1619 {
1620         const char *unknown_name = "SMBunknown";
1621
1622         if (smb_messages[type].name == NULL)
1623                 return(unknown_name);
1624
1625         return(smb_messages[type].name);
1626 }
1627
1628 /****************************************************************************
1629  Helper functions for contruct_reply.
1630 ****************************************************************************/
1631
1632 static uint32 common_flags2 = FLAGS2_LONG_PATH_COMPONENTS|FLAGS2_32_BIT_ERROR_CODES;
1633
1634 void add_to_common_flags2(uint32 v)
1635 {
1636         common_flags2 |= v;
1637 }
1638
1639 void remove_from_common_flags2(uint32 v)
1640 {
1641         common_flags2 &= ~v;
1642 }
1643
1644 void construct_reply_common(const char *inbuf, char *outbuf)
1645 {
1646         srv_set_message(outbuf,0,0,false);
1647
1648         SCVAL(outbuf,smb_com,CVAL(inbuf,smb_com));
1649         SIVAL(outbuf,smb_rcls,0);
1650         SCVAL(outbuf,smb_flg, FLAG_REPLY | (CVAL(inbuf,smb_flg) & FLAG_CASELESS_PATHNAMES));
1651         SSVAL(outbuf,smb_flg2,
1652                 (SVAL(inbuf,smb_flg2) & FLAGS2_UNICODE_STRINGS) |
1653                 common_flags2);
1654         memset(outbuf+smb_pidhigh,'\0',(smb_tid-smb_pidhigh));
1655
1656         SSVAL(outbuf,smb_tid,SVAL(inbuf,smb_tid));
1657         SSVAL(outbuf,smb_pid,SVAL(inbuf,smb_pid));
1658         SSVAL(outbuf,smb_uid,SVAL(inbuf,smb_uid));
1659         SSVAL(outbuf,smb_mid,SVAL(inbuf,smb_mid));
1660 }
1661
1662 /****************************************************************************
1663  Construct a chained reply and add it to the already made reply
1664 ****************************************************************************/
1665
1666 void chain_reply(struct smb_request *req)
1667 {
1668         static char *orig_inbuf;
1669
1670         /*
1671          * Dirty little const_discard: We mess with req->inbuf, which is
1672          * declared as const. If maybe at some point this routine gets
1673          * rewritten, this const_discard could go away.
1674          */
1675         char *inbuf = CONST_DISCARD(char *, req->inbuf);
1676         int size = smb_len(req->inbuf)+4;
1677
1678         int smb_com1, smb_com2 = CVAL(inbuf,smb_vwv0);
1679         unsigned smb_off2 = SVAL(inbuf,smb_vwv1);
1680         char *inbuf2;
1681         int outsize2;
1682         int new_size;
1683         char inbuf_saved[smb_wct];
1684         char *outbuf = (char *)req->outbuf;
1685         size_t outsize = smb_len(outbuf) + 4;
1686         size_t outsize_padded;
1687         size_t ofs, to_move;
1688
1689         struct smb_request *req2;
1690         size_t caller_outputlen;
1691         char *caller_output;
1692
1693         /* Maybe its not chained, or it's an error packet. */
1694         if (smb_com2 == 0xFF || SVAL(outbuf,smb_rcls) != 0) {
1695                 SCVAL(outbuf,smb_vwv0,0xFF);
1696                 return;
1697         }
1698
1699         if (chain_size == 0) {
1700                 /* this is the first part of the chain */
1701                 orig_inbuf = inbuf;
1702         }
1703
1704         /*
1705          * We need to save the output the caller added to the chain so that we
1706          * can splice it into the final output buffer later.
1707          */
1708
1709         caller_outputlen = outsize - smb_wct;
1710
1711         caller_output = (char *)memdup(outbuf + smb_wct, caller_outputlen);
1712
1713         if (caller_output == NULL) {
1714                 /* TODO: NT_STATUS_NO_MEMORY */
1715                 smb_panic("could not dup outbuf");
1716         }
1717
1718         /*
1719          * The original Win95 redirector dies on a reply to
1720          * a lockingX and read chain unless the chain reply is
1721          * 4 byte aligned. JRA.
1722          */
1723
1724         outsize_padded = (outsize + 3) & ~3;
1725
1726         /*
1727          * remember how much the caller added to the chain, only counting
1728          * stuff after the parameter words
1729          */
1730         chain_size += outsize_padded - smb_wct;
1731
1732         /*
1733          * work out pointers into the original packets. The
1734          * headers on these need to be filled in
1735          */
1736         inbuf2 = orig_inbuf + smb_off2 + 4 - smb_wct;
1737
1738         /* remember the original command type */
1739         smb_com1 = CVAL(orig_inbuf,smb_com);
1740
1741         /* save the data which will be overwritten by the new headers */
1742         memcpy(inbuf_saved,inbuf2,smb_wct);
1743
1744         /* give the new packet the same header as the last part of the SMB */
1745         memmove(inbuf2,inbuf,smb_wct);
1746
1747         /* create the in buffer */
1748         SCVAL(inbuf2,smb_com,smb_com2);
1749
1750         /* work out the new size for the in buffer. */
1751         new_size = size - (inbuf2 - inbuf);
1752         if (new_size < 0) {
1753                 DEBUG(0,("chain_reply: chain packet size incorrect "
1754                          "(orig size = %d, offset = %d)\n",
1755                          size, (int)(inbuf2 - inbuf) ));
1756                 exit_server_cleanly("Bad chained packet");
1757                 return;
1758         }
1759
1760         /* And set it in the header. */
1761         smb_setlen(inbuf2, new_size - 4);
1762
1763         DEBUG(3,("Chained message\n"));
1764         show_msg(inbuf2);
1765
1766         if (!(req2 = talloc(talloc_tos(), struct smb_request))) {
1767                 smb_panic("could not allocate smb_request");
1768         }
1769         init_smb_request(req2, (uint8 *)inbuf2,0, req->encrypted);
1770
1771         /* process the request */
1772         switch_message(smb_com2, req2, new_size);
1773
1774         /*
1775          * We don't accept deferred operations in chained requests.
1776          */
1777         SMB_ASSERT(req2->outbuf != NULL);
1778         outsize2 = smb_len(req2->outbuf)+4;
1779
1780         /*
1781          * Move away the new command output so that caller_output fits in,
1782          * copy in the caller_output saved above.
1783          */
1784
1785         SMB_ASSERT(outsize_padded >= smb_wct);
1786
1787         /*
1788          * "ofs" is the space we need for caller_output. Equal to
1789          * caller_outputlen plus the padding.
1790          */
1791
1792         ofs = outsize_padded - smb_wct;
1793
1794         /*
1795          * "to_move" is the amount of bytes the secondary routine gave us
1796          */
1797
1798         to_move = outsize2 - smb_wct;
1799
1800         if (to_move + ofs + smb_wct + chain_size > max_send) {
1801                 smb_panic("replies too large -- would have to cut");
1802         }
1803
1804         /*
1805          * In the "new" API "outbuf" is allocated via reply_outbuf, just for
1806          * the first request in the chain. So we have to re-allocate it. In
1807          * the "old" API the only outbuf ever used is the global OutBuffer
1808          * which is always large enough.
1809          */
1810
1811         outbuf = TALLOC_REALLOC_ARRAY(NULL, outbuf, char,
1812                                       to_move + ofs + smb_wct);
1813         if (outbuf == NULL) {
1814                 smb_panic("could not realloc outbuf");
1815         }
1816
1817         req->outbuf = (uint8 *)outbuf;
1818
1819         memmove(outbuf + smb_wct + ofs, req2->outbuf + smb_wct, to_move);
1820         memcpy(outbuf + smb_wct, caller_output, caller_outputlen);
1821
1822         /*
1823          * copy the new reply header over the old one but preserve the smb_com
1824          * field
1825          */
1826         memmove(outbuf, req2->outbuf, smb_wct);
1827         SCVAL(outbuf, smb_com, smb_com1);
1828
1829         /*
1830          * We've just copied in the whole "wct" area from the secondary
1831          * function. Fix up the chaining: com2 and the offset need to be
1832          * readjusted.
1833          */
1834
1835         SCVAL(outbuf, smb_vwv0, smb_com2);
1836         SSVAL(outbuf, smb_vwv1, chain_size + smb_wct - 4);
1837
1838         if (outsize_padded > outsize) {
1839
1840                 /*
1841                  * Due to padding we have some uninitialized bytes after the
1842                  * caller's output
1843                  */
1844
1845                 memset(outbuf + outsize, 0, outsize_padded - outsize);
1846         }
1847
1848         smb_setlen(outbuf, outsize2 + chain_size - 4);
1849
1850         /*
1851          * restore the saved data, being careful not to overwrite any data
1852          * from the reply header
1853          */
1854         memcpy(inbuf2,inbuf_saved,smb_wct);
1855
1856         SAFE_FREE(caller_output);
1857         TALLOC_FREE(req2);
1858
1859         return;
1860 }
1861
1862 /****************************************************************************
1863  Setup the needed select timeout in milliseconds.
1864 ****************************************************************************/
1865
1866 static int setup_select_timeout(void)
1867 {
1868         int select_timeout;
1869
1870         select_timeout = SMBD_SELECT_TIMEOUT*1000;
1871
1872         if (print_notify_messages_pending()) {
1873                 select_timeout = MIN(select_timeout, 1000);
1874         }
1875
1876         return select_timeout;
1877 }
1878
1879 /****************************************************************************
1880  Check if services need reloading.
1881 ****************************************************************************/
1882
1883 void check_reload(time_t t)
1884 {
1885         static pid_t mypid = 0;
1886         static time_t last_smb_conf_reload_time = 0;
1887         static time_t last_printer_reload_time = 0;
1888         time_t printcap_cache_time = (time_t)lp_printcap_cache_time();
1889
1890         if(last_smb_conf_reload_time == 0) {
1891                 last_smb_conf_reload_time = t;
1892                 /* Our printing subsystem might not be ready at smbd start up.
1893                    Then no printer is available till the first printers check
1894                    is performed.  A lower initial interval circumvents this. */
1895                 if ( printcap_cache_time > 60 )
1896                         last_printer_reload_time = t - printcap_cache_time + 60;
1897                 else
1898                         last_printer_reload_time = t;
1899         }
1900
1901         if (mypid != getpid()) { /* First time or fork happened meanwhile */
1902                 /* randomize over 60 second the printcap reload to avoid all
1903                  * process hitting cupsd at the same time */
1904                 int time_range = 60;
1905
1906                 last_printer_reload_time += random() % time_range;
1907                 mypid = getpid();
1908         }
1909
1910         if (reload_after_sighup || (t >= last_smb_conf_reload_time+SMBD_RELOAD_CHECK)) {
1911                 reload_services(True);
1912                 reload_after_sighup = False;
1913                 last_smb_conf_reload_time = t;
1914         }
1915
1916         /* 'printcap cache time = 0' disable the feature */
1917
1918         if ( printcap_cache_time != 0 )
1919         {
1920                 /* see if it's time to reload or if the clock has been set back */
1921
1922                 if ( (t >= last_printer_reload_time+printcap_cache_time)
1923                         || (t-last_printer_reload_time  < 0) )
1924                 {
1925                         DEBUG( 3,( "Printcap cache time expired.\n"));
1926                         reload_printers();
1927                         last_printer_reload_time = t;
1928                 }
1929         }
1930 }
1931
1932 /****************************************************************************
1933  Process any timeout housekeeping. Return False if the caller should exit.
1934 ****************************************************************************/
1935
1936 static bool timeout_processing(int *select_timeout,
1937                                time_t *last_timeout_processing_time)
1938 {
1939         time_t t;
1940
1941         if (*get_srv_read_error() == SMB_READ_EOF) {
1942                 DEBUG(3,("timeout_processing: End of file from client (client has disconnected).\n"));
1943                 return false;
1944         }
1945
1946         if (*get_srv_read_error() == SMB_READ_ERROR) {
1947                 DEBUG(3,("timeout_processing: receive_smb error (%s) Exiting\n",
1948                         strerror(errno)));
1949                 return false;
1950         }
1951
1952         if (*get_srv_read_error() == SMB_READ_BAD_SIG) {
1953                 DEBUG(3,("timeout_processing: receive_smb error bad smb signature. Exiting\n"));
1954                 return false;
1955         }
1956
1957         *last_timeout_processing_time = t = time(NULL);
1958
1959         /* become root again if waiting */
1960         change_to_root_user();
1961
1962         /* check if we need to reload services */
1963         check_reload(t);
1964
1965         if(global_machine_password_needs_changing &&
1966                         /* for ADS we need to do a regular ADS password change, not a domain
1967                                         password change */
1968                         lp_security() == SEC_DOMAIN) {
1969
1970                 unsigned char trust_passwd_hash[16];
1971                 time_t lct;
1972
1973                 /*
1974                  * We're in domain level security, and the code that
1975                  * read the machine password flagged that the machine
1976                  * password needs changing.
1977                  */
1978
1979                 /*
1980                  * First, open the machine password file with an exclusive lock.
1981                  */
1982
1983                 if (secrets_lock_trust_account_password(lp_workgroup(), True) == False) {
1984                         DEBUG(0,("process: unable to lock the machine account password for \
1985 machine %s in domain %s.\n", global_myname(), lp_workgroup() ));
1986                         return True;
1987                 }
1988
1989                 if(!secrets_fetch_trust_account_password(lp_workgroup(), trust_passwd_hash, &lct, NULL)) {
1990                         DEBUG(0,("process: unable to read the machine account password for \
1991 machine %s in domain %s.\n", global_myname(), lp_workgroup()));
1992                         secrets_lock_trust_account_password(lp_workgroup(), False);
1993                         return True;
1994                 }
1995
1996                 /*
1997                  * Make sure someone else hasn't already done this.
1998                  */
1999
2000                 if(t < lct + lp_machine_password_timeout()) {
2001                         global_machine_password_needs_changing = False;
2002                         secrets_lock_trust_account_password(lp_workgroup(), False);
2003                         return True;
2004                 }
2005
2006                 /* always just contact the PDC here */
2007
2008                 change_trust_account_password( lp_workgroup(), NULL);
2009                 global_machine_password_needs_changing = False;
2010                 secrets_lock_trust_account_password(lp_workgroup(), False);
2011         }
2012
2013         /* update printer queue caches if necessary */
2014
2015         update_monitored_printq_cache();
2016
2017         /*
2018          * Now we are root, check if the log files need pruning.
2019          * Force a log file check.
2020          */
2021         force_check_log_size();
2022         check_log_size();
2023
2024         /* Send any queued printer notify message to interested smbd's. */
2025
2026         print_notify_send_messages(smbd_messaging_context(), 0);
2027
2028         /*
2029          * Modify the select timeout depending upon
2030          * what we have remaining in our queues.
2031          */
2032
2033         *select_timeout = setup_select_timeout();
2034
2035         return True;
2036 }
2037
2038 /****************************************************************************
2039  Process commands from the client
2040 ****************************************************************************/
2041
2042 void smbd_process(void)
2043 {
2044         time_t last_timeout_processing_time = time(NULL);
2045         unsigned int num_smbs = 0;
2046         size_t unread_bytes = 0;
2047
2048         max_recv = MIN(lp_maxxmit(),BUFFER_SIZE);
2049
2050         while (True) {
2051                 int select_timeout = setup_select_timeout();
2052                 int num_echos;
2053                 char *inbuf;
2054                 size_t inbuf_len;
2055                 bool encrypted = false;
2056                 TALLOC_CTX *frame = talloc_stackframe_pool(8192);
2057
2058                 errno = 0;
2059
2060                 /* Did someone ask for immediate checks on things like blocking locks ? */
2061                 if (select_timeout == 0) {
2062                         if(!timeout_processing(&select_timeout,
2063                                                &last_timeout_processing_time))
2064                                 return;
2065                         num_smbs = 0; /* Reset smb counter. */
2066                 }
2067
2068                 run_events(smbd_event_context(), 0, NULL, NULL);
2069
2070                 while (!receive_message_or_smb(talloc_tos(), &inbuf, &inbuf_len,
2071                                                 select_timeout,
2072                                                 &unread_bytes,
2073                                                 &encrypted)) {
2074                         if(!timeout_processing(&select_timeout,
2075                                                &last_timeout_processing_time))
2076                                 return;
2077                         num_smbs = 0; /* Reset smb counter. */
2078                 }
2079
2080
2081                 /*
2082                  * Ensure we do timeout processing if the SMB we just got was
2083                  * only an echo request. This allows us to set the select
2084                  * timeout in 'receive_message_or_smb()' to any value we like
2085                  * without worrying that the client will send echo requests
2086                  * faster than the select timeout, thus starving out the
2087                  * essential processing (change notify, blocking locks) that
2088                  * the timeout code does. JRA.
2089                  */
2090                 num_echos = smb_echo_count;
2091
2092                 process_smb(inbuf, inbuf_len, unread_bytes, encrypted);
2093
2094                 TALLOC_FREE(inbuf);
2095
2096                 if (smb_echo_count != num_echos) {
2097                         if(!timeout_processing( &select_timeout, &last_timeout_processing_time))
2098                                 return;
2099                         num_smbs = 0; /* Reset smb counter. */
2100                 }
2101
2102                 num_smbs++;
2103
2104                 /*
2105                  * If we are getting smb requests in a constant stream
2106                  * with no echos, make sure we attempt timeout processing
2107                  * every select_timeout milliseconds - but only check for this
2108                  * every 200 smb requests.
2109                  */
2110
2111                 if ((num_smbs % 200) == 0) {
2112                         time_t new_check_time = time(NULL);
2113                         if(new_check_time - last_timeout_processing_time >= (select_timeout/1000)) {
2114                                 if(!timeout_processing(
2115                                            &select_timeout,
2116                                            &last_timeout_processing_time))
2117                                         return;
2118                                 num_smbs = 0; /* Reset smb counter. */
2119                                 last_timeout_processing_time = new_check_time; /* Reset time. */
2120                         }
2121                 }
2122
2123                 /* The timeout_processing function isn't run nearly
2124                    often enough to implement 'max log size' without
2125                    overrunning the size of the file by many megabytes.
2126                    This is especially true if we are running at debug
2127                    level 10.  Checking every 50 SMBs is a nice
2128                    tradeoff of performance vs log file size overrun. */
2129
2130                 if ((num_smbs % 50) == 0 && need_to_check_log_size()) {
2131                         change_to_root_user();
2132                         check_log_size();
2133                 }
2134                 TALLOC_FREE(frame);
2135         }
2136 }