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 /*
  24  * Size of data we can send to client. Set
  25  *  by the client for all protocols above CORE.
  26  *  Set by us for CORE protocol.
  27  */
  28 int max_send = BUFFER_SIZE;
  29 /*
  30  * Size of the data we can receive. Set by us.
  31  * Can be modified by the max xmit parameter.
  32  */
  33 int max_recv = BUFFER_SIZE;
  34
  35 SIG_ATOMIC_T reload_after_sighup = 0;
  36 SIG_ATOMIC_T got_sig_term = 0;
  37 extern bool global_machine_password_needs_changing;
  38 extern int max_send;
  39
  40 /* Accessor function for smb_read_error for smbd functions. */
  41
  42 /****************************************************************************
  43  Send an smb to a fd.
  44 ****************************************************************************/
  45
  46 bool srv_send_smb(int fd, char *buffer, bool do_encrypt)
  47 {
  48         size_t len;
  49         size_t nwritten=0;
  50         ssize_t ret;
  51         char *buf_out = buffer;
  52
  53         /* Sign the outgoing packet if required. */
  54         srv_calculate_sign_mac(buf_out);
  55
  56         if (do_encrypt) {
  57                 NTSTATUS status = srv_encrypt_buffer(buffer, &buf_out);
  58                 if (!NT_STATUS_IS_OK(status)) {
  59                         DEBUG(0, ("send_smb: SMB encryption failed "
  60                                 "on outgoing packet! Error %s\n",
  61                                 nt_errstr(status) ));
  62                         return false;
  63                 }
  64         }
  65
  66         len = smb_len(buf_out) + 4;
  67
  68         while (nwritten < len) {
  69                 ret = write_data(fd,buf_out+nwritten,len - nwritten);
  70                 if (ret <= 0) {
  71                         DEBUG(0,("Error writing %d bytes to client. %d. (%s)\n",
  72                                 (int)len,(int)ret, strerror(errno) ));
  73                         srv_free_enc_buffer(buf_out);
  74                         return false;
  75                 }
  76                 nwritten += ret;
  77         }
  78
  79         srv_free_enc_buffer(buf_out);
  80         return true;
  81 }
  82
  83 /*******************************************************************
  84  Setup the word count and byte count for a smb message.
  85 ********************************************************************/
  86
  87 int srv_set_message(char *buf,
  88                         int num_words,
  89                         int num_bytes,
  90                         bool zero)
  91 {
  92         if (zero && (num_words || num_bytes)) {
  93                 memset(buf + smb_size,'\0',num_words*2 + num_bytes);
  94         }
  95         SCVAL(buf,smb_wct,num_words);
  96         SSVAL(buf,smb_vwv + num_words*SIZEOFWORD,num_bytes);
  97         smb_setlen(buf,(smb_size + num_words*2 + num_bytes - 4));
  98         return (smb_size + num_words*2 + num_bytes);
  99 }
 100
 101 static bool valid_smb_header(const uint8_t *inbuf)
 102 {
 103         if (is_encrypted_packet(inbuf)) {
 104                 return true;
 105         }
 106         /*
 107          * This used to be (strncmp(smb_base(inbuf),"\377SMB",4) == 0)
 108          * but it just looks weird to call strncmp for this one.
 109          */
 110         return (IVAL(smb_base(inbuf), 0) == 0x424D53FF);
 111 }
 112
 113 /* Socket functions for smbd packet processing. */
 114
 115 static bool valid_packet_size(size_t len)
 116 {
 117         /*
 118          * A WRITEX with CAP_LARGE_WRITEX can be 64k worth of data plus 65 bytes
 119          * of header. Don't print the error if this fits.... JRA.
 120          */
 121
 122         if (len > (BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE)) {
 123                 DEBUG(0,("Invalid packet length! (%lu bytes).\n",
 124                                         (unsigned long)len));
 125                 return false;
 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, 4);
 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                         DEBUG(10, ("receive_smb_raw_talloc_partial_read: %s\n",
 256                                    nt_errstr(status)));
 257                         return status;
 258                 }
 259         }
 260
 261         *len_ret = len + 4;
 262         return NT_STATUS_OK;
 263 }
 264
 265 static NTSTATUS receive_smb_raw_talloc(TALLOC_CTX *mem_ctx, int fd,
 266                                        char **buffer, unsigned int timeout,
 267                                        size_t *p_unread, size_t *plen)
 268 {
 269         char lenbuf[4];
 270         size_t len;
 271         int min_recv_size = lp_min_receive_file_size();
 272         NTSTATUS status;
 273
 274         *p_unread = 0;
 275
 276         status = read_smb_length_return_keepalive(fd, lenbuf, timeout, &len);
 277         if (!NT_STATUS_IS_OK(status)) {
 278                 DEBUG(10, ("receive_smb_raw: %s\n", nt_errstr(status)));
 279                 return status;
 280         }
 281
 282         if (CVAL(lenbuf,0) == 0 &&
 283                         min_recv_size &&
 284                         smb_len_large(lenbuf) > min_recv_size && /* Could be a UNIX large writeX. */
 285                         !srv_is_signing_active()) {
 286
 287                 return receive_smb_raw_talloc_partial_read(
 288                         mem_ctx, lenbuf, fd, buffer, timeout, p_unread, plen);
 289         }
 290
 291         if (!valid_packet_size(len)) {
 292                 return NT_STATUS_INVALID_PARAMETER;
 293         }
 294
 295         /*
 296          * The +4 here can't wrap, we've checked the length above already.
 297          */
 298
 299         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
 300
 301         if (*buffer == NULL) {
 302                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
 303                           (int)len+4));
 304                 return NT_STATUS_NO_MEMORY;
 305         }
 306
 307         memcpy(*buffer, lenbuf, sizeof(lenbuf));
 308
 309         status = read_packet_remainder(fd, (*buffer)+4, timeout, len);
 310         if (!NT_STATUS_IS_OK(status)) {
 311                 return status;
 312         }
 313
 314         *plen = len + 4;
 315         return NT_STATUS_OK;
 316 }
 317
 318 static NTSTATUS receive_smb_talloc(TALLOC_CTX *mem_ctx, int fd,
 319                                    char **buffer, unsigned int timeout,
 320                                    size_t *p_unread, bool *p_encrypted,
 321                                    size_t *p_len)
 322 {
 323         size_t len = 0;
 324         NTSTATUS status;
 325
 326         *p_encrypted = false;
 327
 328         status = receive_smb_raw_talloc(mem_ctx, fd, buffer, timeout,
 329                                         p_unread, &len);
 330         if (!NT_STATUS_IS_OK(status)) {
 331                 return status;
 332         }
 333
 334         if (is_encrypted_packet((uint8_t *)*buffer)) {
 335                 status = srv_decrypt_buffer(*buffer);
 336                 if (!NT_STATUS_IS_OK(status)) {
 337                         DEBUG(0, ("receive_smb_talloc: SMB decryption failed on "
 338                                 "incoming packet! Error %s\n",
 339                                 nt_errstr(status) ));
 340                         return status;
 341                 }
 342                 *p_encrypted = true;
 343         }
 344
 345         /* Check the incoming SMB signature. */
 346         if (!srv_check_sign_mac(*buffer, true)) {
 347                 DEBUG(0, ("receive_smb: SMB Signature verification failed on "
 348                           "incoming packet!\n"));
 349                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
 350         }
 351
 352         *p_len = len;
 353         return NT_STATUS_OK;
 354 }
 355
 356 /*
 357  * Initialize a struct smb_request from an inbuf
 358  */
 359
 360 void init_smb_request(struct smb_request *req,
 361                         const uint8 *inbuf,
 362                         size_t unread_bytes,
 363                         bool encrypted)
 364 {
 365         size_t req_size = smb_len(inbuf) + 4;
 366         /* Ensure we have at least smb_size bytes. */
 367         if (req_size < smb_size) {
 368                 DEBUG(0,("init_smb_request: invalid request size %u\n",
 369                         (unsigned int)req_size ));
 370                 exit_server_cleanly("Invalid SMB request");
 371         }
 372         req->cmd    = CVAL(inbuf, smb_com);
 373         req->flags2 = SVAL(inbuf, smb_flg2);
 374         req->smbpid = SVAL(inbuf, smb_pid);
 375         req->mid    = SVAL(inbuf, smb_mid);
 376         req->vuid   = SVAL(inbuf, smb_uid);
 377         req->tid    = SVAL(inbuf, smb_tid);
 378         req->wct    = CVAL(inbuf, smb_wct);
 379         req->vwv    = (uint16_t *)(inbuf+smb_vwv);
 380         req->buflen = smb_buflen(inbuf);
 381         req->buf    = (const uint8_t *)smb_buf(inbuf);
 382         req->unread_bytes = unread_bytes;
 383         req->encrypted = encrypted;
 384         req->conn = conn_find(req->tid);
 385         req->chain_fsp = NULL;
 386
 387         /* Ensure we have at least wct words and 2 bytes of bcc. */
 388         if (smb_size + req->wct*2 > req_size) {
 389                 DEBUG(0,("init_smb_request: invalid wct number %u (size %u)\n",
 390                         (unsigned int)req->wct,
 391                         (unsigned int)req_size));
 392                 exit_server_cleanly("Invalid SMB request");
 393         }
 394         /* Ensure bcc is correct. */
 395         if (((uint8 *)smb_buf(inbuf)) + req->buflen > inbuf + req_size) {
 396                 DEBUG(0,("init_smb_request: invalid bcc number %u "
 397                         "(wct = %u, size %u)\n",
 398                         (unsigned int)req->buflen,
 399                         (unsigned int)req->wct,
 400                         (unsigned int)req_size));
 401                 exit_server_cleanly("Invalid SMB request");
 402         }
 403         req->inbuf  = inbuf;
 404         req->outbuf = NULL;
 405 }
 406
 407 /****************************************************************************
 408  structure to hold a linked list of queued messages.
 409  for processing.
 410 ****************************************************************************/
 411
 412 static struct pending_message_list *deferred_open_queue;
 413
 414 /****************************************************************************
 415  Function to push a message onto the tail of a linked list of smb messages ready
 416  for processing.
 417 ****************************************************************************/
 418
 419 static bool push_queued_message(struct smb_request *req,
 420                                 struct timeval request_time,
 421                                 struct timeval end_time,
 422                                 char *private_data, size_t private_len)
 423 {
 424         int msg_len = smb_len(req->inbuf) + 4;
 425         struct pending_message_list *msg;
 426
 427         msg = TALLOC_ZERO_P(NULL, struct pending_message_list);
 428
 429         if(msg == NULL) {
 430                 DEBUG(0,("push_message: malloc fail (1)\n"));
 431                 return False;
 432         }
 433
 434         msg->buf = data_blob_talloc(msg, req->inbuf, msg_len);
 435         if(msg->buf.data == NULL) {
 436                 DEBUG(0,("push_message: malloc fail (2)\n"));
 437                 TALLOC_FREE(msg);
 438                 return False;
 439         }
 440
 441         msg->request_time = request_time;
 442         msg->end_time = end_time;
 443         msg->encrypted = req->encrypted;
 444
 445         if (private_data) {
 446                 msg->private_data = data_blob_talloc(msg, private_data,
 447                                                      private_len);
 448                 if (msg->private_data.data == NULL) {
 449                         DEBUG(0,("push_message: malloc fail (3)\n"));
 450                         TALLOC_FREE(msg);
 451                         return False;
 452                 }
 453         }
 454
 455         DLIST_ADD_END(deferred_open_queue, msg, struct pending_message_list *);
 456
 457         DEBUG(10,("push_message: pushed message length %u on "
 458                   "deferred_open_queue\n", (unsigned int)msg_len));
 459
 460         return True;
 461 }
 462
 463 /****************************************************************************
 464  Function to delete a sharing violation open message by mid.
 465 ****************************************************************************/
 466
 467 void remove_deferred_open_smb_message(uint16 mid)
 468 {
 469         struct pending_message_list *pml;
 470
 471         for (pml = deferred_open_queue; pml; pml = pml->next) {
 472                 if (mid == SVAL(pml->buf.data,smb_mid)) {
 473                         DEBUG(10,("remove_sharing_violation_open_smb_message: "
 474                                   "deleting mid %u len %u\n",
 475                                   (unsigned int)mid,
 476                                   (unsigned int)pml->buf.length ));
 477                         DLIST_REMOVE(deferred_open_queue, pml);
 478                         TALLOC_FREE(pml);
 479                         return;
 480                 }
 481         }
 482 }
 483
 484 /****************************************************************************
 485  Move a sharing violation open retry message to the front of the list and
 486  schedule it for immediate processing.
 487 ****************************************************************************/
 488
 489 void schedule_deferred_open_smb_message(uint16 mid)
 490 {
 491         struct pending_message_list *pml;
 492         int i = 0;
 493
 494         for (pml = deferred_open_queue; pml; pml = pml->next) {
 495                 uint16 msg_mid = SVAL(pml->buf.data,smb_mid);
 496                 DEBUG(10,("schedule_deferred_open_smb_message: [%d] msg_mid = %u\n", i++,
 497                         (unsigned int)msg_mid ));
 498                 if (mid == msg_mid) {
 499                         DEBUG(10,("schedule_deferred_open_smb_message: scheduling mid %u\n",
 500                                 mid ));
 501                         pml->end_time.tv_sec = 0;
 502                         pml->end_time.tv_usec = 0;
 503                         DLIST_PROMOTE(deferred_open_queue, pml);
 504                         return;
 505                 }
 506         }
 507
 508         DEBUG(10,("schedule_deferred_open_smb_message: failed to find message mid %u\n",
 509                 mid ));
 510 }
 511
 512 /****************************************************************************
 513  Return true if this mid is on the deferred queue.
 514 ****************************************************************************/
 515
 516 bool open_was_deferred(uint16 mid)
 517 {
 518         struct pending_message_list *pml;
 519
 520         for (pml = deferred_open_queue; pml; pml = pml->next) {
 521                 if (SVAL(pml->buf.data,smb_mid) == mid) {
 522                         return True;
 523                 }
 524         }
 525         return False;
 526 }
 527
 528 /****************************************************************************
 529  Return the message queued by this mid.
 530 ****************************************************************************/
 531
 532 struct pending_message_list *get_open_deferred_message(uint16 mid)
 533 {
 534         struct pending_message_list *pml;
 535
 536         for (pml = deferred_open_queue; pml; pml = pml->next) {
 537                 if (SVAL(pml->buf.data,smb_mid) == mid) {
 538                         return pml;
 539                 }
 540         }
 541         return NULL;
 542 }
 543
 544 /****************************************************************************
 545  Function to push a deferred open smb message onto a linked list of local smb
 546  messages ready for processing.
 547 ****************************************************************************/
 548
 549 bool push_deferred_smb_message(struct smb_request *req,
 550                                struct timeval request_time,
 551                                struct timeval timeout,
 552                                char *private_data, size_t priv_len)
 553 {
 554         struct timeval end_time;
 555
 556         if (req->unread_bytes) {
 557                 DEBUG(0,("push_deferred_smb_message: logic error ! "
 558                         "unread_bytes = %u\n",
 559                         (unsigned int)req->unread_bytes ));
 560                 smb_panic("push_deferred_smb_message: "
 561                         "logic error unread_bytes != 0" );
 562         }
 563
 564         end_time = timeval_sum(&request_time, &timeout);
 565
 566         DEBUG(10,("push_deferred_open_smb_message: pushing message len %u mid %u "
 567                   "timeout time [%u.%06u]\n",
 568                   (unsigned int) smb_len(req->inbuf)+4, (unsigned int)req->mid,
 569                   (unsigned int)end_time.tv_sec,
 570                   (unsigned int)end_time.tv_usec));
 571
 572         return push_queued_message(req, request_time, end_time,
 573                                    private_data, priv_len);
 574 }
 575
 576 struct idle_event {
 577         struct timed_event *te;
 578         struct timeval interval;
 579         char *name;
 580         bool (*handler)(const struct timeval *now, void *private_data);
 581         void *private_data;
 582 };
 583
 584 static void idle_event_handler(struct event_context *ctx,
 585                                struct timed_event *te,
 586                                const struct timeval *now,
 587                                void *private_data)
 588 {
 589         struct idle_event *event =
 590                 talloc_get_type_abort(private_data, struct idle_event);
 591
 592         TALLOC_FREE(event->te);
 593
 594         if (!event->handler(now, event->private_data)) {
 595                 /* Don't repeat, delete ourselves */
 596                 TALLOC_FREE(event);
 597                 return;
 598         }
 599
 600         event->te = event_add_timed(ctx, event,
 601                                     timeval_sum(now, &event->interval),
 602                                     event->name,
 603                                     idle_event_handler, event);
 604
 605         /* We can't do much but fail here. */
 606         SMB_ASSERT(event->te != NULL);
 607 }
 608
 609 struct idle_event *event_add_idle(struct event_context *event_ctx,
 610                                   TALLOC_CTX *mem_ctx,
 611                                   struct timeval interval,
 612                                   const char *name,
 613                                   bool (*handler)(const struct timeval *now,
 614                                                   void *private_data),
 615                                   void *private_data)
 616 {
 617         struct idle_event *result;
 618         struct timeval now = timeval_current();
 619
 620         result = TALLOC_P(mem_ctx, struct idle_event);
 621         if (result == NULL) {
 622                 DEBUG(0, ("talloc failed\n"));
 623                 return NULL;
 624         }
 625
 626         result->interval = interval;
 627         result->handler = handler;
 628         result->private_data = private_data;
 629
 630         if (!(result->name = talloc_asprintf(result, "idle_evt(%s)", name))) {
 631                 DEBUG(0, ("talloc failed\n"));
 632                 TALLOC_FREE(result);
 633                 return NULL;
 634         }
 635
 636         result->te = event_add_timed(event_ctx, result,
 637                                      timeval_sum(&now, &interval),
 638                                      result->name,
 639                                      idle_event_handler, result);
 640         if (result->te == NULL) {
 641                 DEBUG(0, ("event_add_timed failed\n"));
 642                 TALLOC_FREE(result);
 643                 return NULL;
 644         }
 645
 646         return result;
 647 }
 648
 649 /****************************************************************************
 650  Do all async processing in here. This includes kernel oplock messages, change
 651  notify events etc.
 652 ****************************************************************************/
 653
 654 static void async_processing(fd_set *pfds)
 655 {
 656         DEBUG(10,("async_processing: Doing async processing.\n"));
 657
 658         process_aio_queue();
 659
 660         process_kernel_oplocks(smbd_messaging_context(), pfds);
 661
 662         /* Do the aio check again after receive_local_message as it does a
 663            select and may have eaten our signal. */
 664         /* Is this till true? -- vl */
 665         process_aio_queue();
 666
 667         if (got_sig_term) {
 668                 exit_server_cleanly("termination signal");
 669         }
 670
 671         /* check for sighup processing */
 672         if (reload_after_sighup) {
 673                 change_to_root_user();
 674                 DEBUG(1,("Reloading services after SIGHUP\n"));
 675                 reload_services(False);
 676                 reload_after_sighup = 0;
 677         }
 678 }
 679
 680 /****************************************************************************
 681  Add a fd to the set we will be select(2)ing on.
 682 ****************************************************************************/
 683
 684 static int select_on_fd(int fd, int maxfd, fd_set *fds)
 685 {
 686         if (fd != -1) {
 687                 FD_SET(fd, fds);
 688                 maxfd = MAX(maxfd, fd);
 689         }
 690
 691         return maxfd;
 692 }
 693
 694 /****************************************************************************
 695   Do a select on an two fd's - with timeout.
 696
 697   If a local udp message has been pushed onto the
 698   queue (this can only happen during oplock break
 699   processing) call async_processing()
 700
 701   If a pending smb message has been pushed onto the
 702   queue (this can only happen during oplock break
 703   processing) return this next.
 704
 705   If the first smbfd is ready then read an smb from it.
 706   if the second (loopback UDP) fd is ready then read a message
 707   from it and setup the buffer header to identify the length
 708   and from address.
 709   Returns False on timeout or error.
 710   Else returns True.
 711
 712 The timeout is in milliseconds
 713 ****************************************************************************/
 714
 715 static NTSTATUS receive_message_or_smb(TALLOC_CTX *mem_ctx, char **buffer,
 716                                        size_t *buffer_len,
 717                                        size_t *p_unread, bool *p_encrypted)
 718 {
 719         fd_set r_fds, w_fds;
 720         int selrtn;
 721         struct timeval to;
 722         int maxfd = 0;
 723         size_t len = 0;
 724         NTSTATUS status;
 725
 726         *p_unread = 0;
 727
 728  again:
 729
 730         to.tv_sec = SMBD_SELECT_TIMEOUT;
 731         to.tv_usec = 0;
 732
 733         /*
 734          * Note that this call must be before processing any SMB
 735          * messages as we need to synchronously process any messages
 736          * we may have sent to ourselves from the previous SMB.
 737          */
 738         message_dispatch(smbd_messaging_context());
 739
 740         /*
 741          * Check to see if we already have a message on the deferred open queue
 742          * and it's time to schedule.
 743          */
 744         if(deferred_open_queue != NULL) {
 745                 bool pop_message = False;
 746                 struct pending_message_list *msg = deferred_open_queue;
 747
 748                 if (timeval_is_zero(&msg->end_time)) {
 749                         pop_message = True;
 750                 } else {
 751                         struct timeval tv;
 752                         int64_t tdif;
 753
 754                         GetTimeOfDay(&tv);
 755                         tdif = usec_time_diff(&msg->end_time, &tv);
 756                         if (tdif <= 0) {
 757                                 /* Timed out. Schedule...*/
 758                                 pop_message = True;
 759                                 DEBUG(10,("receive_message_or_smb: queued message timed out.\n"));
 760                         } else {
 761                                 /* Make a more accurate select timeout. */
 762                                 to.tv_sec = tdif / 1000000;
 763                                 to.tv_usec = tdif % 1000000;
 764                                 DEBUG(10,("receive_message_or_smb: select with timeout of [%u.%06u]\n",
 765                                         (unsigned int)to.tv_sec, (unsigned int)to.tv_usec ));
 766                         }
 767                 }
 768
 769                 if (pop_message) {
 770
 771                         *buffer = (char *)talloc_memdup(mem_ctx, msg->buf.data,
 772                                                         msg->buf.length);
 773                         if (*buffer == NULL) {
 774                                 DEBUG(0, ("talloc failed\n"));
 775                                 return NT_STATUS_NO_MEMORY;
 776                         }
 777                         *buffer_len = msg->buf.length;
 778                         *p_encrypted = msg->encrypted;
 779
 780                         /* We leave this message on the queue so the open code can
 781                            know this is a retry. */
 782                         DEBUG(5,("receive_message_or_smb: returning deferred open smb message.\n"));
 783                         return NT_STATUS_OK;
 784                 }
 785         }
 786
 787         /*
 788          * Setup the select fd sets.
 789          */
 790
 791         FD_ZERO(&r_fds);
 792         FD_ZERO(&w_fds);
 793
 794         /*
 795          * Ensure we process oplock break messages by preference.
 796          * We have to do this before the select, after the select
 797          * and if the select returns EINTR. This is due to the fact
 798          * that the selects called from async_processing can eat an EINTR
 799          * caused by a signal (we can't take the break message there).
 800          * This is hideously complex - *MUST* be simplified for 3.0 ! JRA.
 801          */
 802
 803         if (oplock_message_waiting(&r_fds)) {
 804                 DEBUG(10,("receive_message_or_smb: oplock_message is waiting.\n"));
 805                 async_processing(&r_fds);
 806                 /*
 807                  * After async processing we must go and do the select again, as
 808                  * the state of the flag in fds for the server file descriptor is
 809                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 810                  */
 811                 goto again;
 812         }
 813
 814         /*
 815          * Are there any timed events waiting ? If so, ensure we don't
 816          * select for longer than it would take to wait for them.
 817          */
 818
 819         {
 820                 struct timeval now;
 821                 GetTimeOfDay(&now);
 822
 823                 event_add_to_select_args(smbd_event_context(), &now,
 824                                          &r_fds, &w_fds, &to, &maxfd);
 825         }
 826
 827         if (timeval_is_zero(&to)) {
 828                 /* Process a timed event now... */
 829                 if (run_events(smbd_event_context(), 0, NULL, NULL)) {
 830                         goto again;
 831                 }
 832         }
 833
 834         {
 835                 int sav;
 836                 START_PROFILE(smbd_idle);
 837
 838                 maxfd = select_on_fd(smbd_server_fd(), maxfd, &r_fds);
 839                 maxfd = select_on_fd(oplock_notify_fd(), maxfd, &r_fds);
 840
 841                 selrtn = sys_select(maxfd+1,&r_fds,&w_fds,NULL,&to);
 842                 sav = errno;
 843
 844                 END_PROFILE(smbd_idle);
 845                 errno = sav;
 846         }
 847
 848         if (run_events(smbd_event_context(), selrtn, &r_fds, &w_fds)) {
 849                 goto again;
 850         }
 851
 852         /* if we get EINTR then maybe we have received an oplock
 853            signal - treat this as select returning 1. This is ugly, but
 854            is the best we can do until the oplock code knows more about
 855            signals */
 856         if (selrtn == -1 && errno == EINTR) {
 857                 async_processing(&r_fds);
 858                 /*
 859                  * After async processing we must go and do the select again, as
 860                  * the state of the flag in fds for the server file descriptor is
 861                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 862                  */
 863                 goto again;
 864         }
 865
 866         /* Check if error */
 867         if (selrtn == -1) {
 868                 /* something is wrong. Maybe the socket is dead? */
 869                 return map_nt_error_from_unix(errno);
 870         }
 871
 872         /* Did we timeout ? */
 873         if (selrtn == 0) {
 874                 goto again;
 875         }
 876
 877         /*
 878          * Ensure we process oplock break messages by preference.
 879          * This is IMPORTANT ! Otherwise we can starve other processes
 880          * sending us an oplock break message. JRA.
 881          */
 882
 883         if (oplock_message_waiting(&r_fds)) {
 884                 async_processing(&r_fds);
 885                 /*
 886                  * After async processing we must go and do the select again, as
 887                  * the state of the flag in fds for the server file descriptor is
 888                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 889                  */
 890                 goto again;
 891         }
 892
 893         /*
 894          * We've just woken up from a protentially long select sleep.
 895          * Ensure we process local messages as we need to synchronously
 896          * process any messages from other smbd's to avoid file rename race
 897          * conditions. This call is cheap if there are no messages waiting.
 898          * JRA.
 899          */
 900         message_dispatch(smbd_messaging_context());
 901
 902         status = receive_smb_talloc(mem_ctx, smbd_server_fd(), buffer, 0,
 903                                     p_unread, p_encrypted, &len);
 904
 905         if (!NT_STATUS_IS_OK(status)) {
 906                 return status;
 907         }
 908
 909         *buffer_len = len;
 910
 911         return NT_STATUS_OK;
 912 }
 913
 914 /*
 915  * Only allow 5 outstanding trans requests. We're allocating memory, so
 916  * prevent a DoS.
 917  */
 918
 919 NTSTATUS allow_new_trans(struct trans_state *list, int mid)
 920 {
 921         int count = 0;
 922         for (; list != NULL; list = list->next) {
 923
 924                 if (list->mid == mid) {
 925                         return NT_STATUS_INVALID_PARAMETER;
 926                 }
 927
 928                 count += 1;
 929         }
 930         if (count > 5) {
 931                 return NT_STATUS_INSUFFICIENT_RESOURCES;
 932         }
 933
 934         return NT_STATUS_OK;
 935 }
 936
 937 /****************************************************************************
 938  We're terminating and have closed all our files/connections etc.
 939  If there are any pending local messages we need to respond to them
 940  before termination so that other smbds don't think we just died whilst
 941  holding oplocks.
 942 ****************************************************************************/
 943
 944 void respond_to_all_remaining_local_messages(void)
 945 {
 946         /*
 947          * Assert we have no exclusive open oplocks.
 948          */
 949
 950         if(get_number_of_exclusive_open_oplocks()) {
 951                 DEBUG(0,("respond_to_all_remaining_local_messages: PANIC : we have %d exclusive oplocks.\n",
 952                         get_number_of_exclusive_open_oplocks() ));
 953                 return;
 954         }
 955
 956         process_kernel_oplocks(smbd_messaging_context(), NULL);
 957
 958         return;
 959 }
 960
 961
 962 /*
 963 These flags determine some of the permissions required to do an operation
 964
 965 Note that I don't set NEED_WRITE on some write operations because they
 966 are used by some brain-dead clients when printing, and I don't want to
 967 force write permissions on print services.
 968 */
 969 #define AS_USER (1<<0)
 970 #define NEED_WRITE (1<<1) /* Must be paired with AS_USER */
 971 #define TIME_INIT (1<<2)
 972 #define CAN_IPC (1<<3) /* Must be paired with AS_USER */
 973 #define AS_GUEST (1<<5) /* Must *NOT* be paired with AS_USER */
 974 #define DO_CHDIR (1<<6)
 975
 976 /*
 977    define a list of possible SMB messages and their corresponding
 978    functions. Any message that has a NULL function is unimplemented -
 979    please feel free to contribute implementations!
 980 */
 981 static const struct smb_message_struct {
 982         const char *name;
 983         void (*fn)(struct smb_request *req);
 984         int flags;
 985 } smb_messages[256] = {
 986
 987 /* 0x00 */ { "SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE},
 988 /* 0x01 */ { "SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE},
 989 /* 0x02 */ { "SMBopen",reply_open,AS_USER },
 990 /* 0x03 */ { "SMBcreate",reply_mknew,AS_USER},
 991 /* 0x04 */ { "SMBclose",reply_close,AS_USER | CAN_IPC },
 992 /* 0x05 */ { "SMBflush",reply_flush,AS_USER},
 993 /* 0x06 */ { "SMBunlink",reply_unlink,AS_USER | NEED_WRITE },
 994 /* 0x07 */ { "SMBmv",reply_mv,AS_USER | NEED_WRITE },
 995 /* 0x08 */ { "SMBgetatr",reply_getatr,AS_USER},
 996 /* 0x09 */ { "SMBsetatr",reply_setatr,AS_USER | NEED_WRITE},
 997 /* 0x0a */ { "SMBread",reply_read,AS_USER},
 998 /* 0x0b */ { "SMBwrite",reply_write,AS_USER | CAN_IPC },
 999 /* 0x0c */ { "SMBlock",reply_lock,AS_USER},
1000 /* 0x0d */ { "SMBunlock",reply_unlock,AS_USER},
1001 /* 0x0e */ { "SMBctemp",reply_ctemp,AS_USER },
1002 /* 0x0f */ { "SMBmknew",reply_mknew,AS_USER},
1003 /* 0x10 */ { "SMBcheckpath",reply_checkpath,AS_USER},
1004 /* 0x11 */ { "SMBexit",reply_exit,DO_CHDIR},
1005 /* 0x12 */ { "SMBlseek",reply_lseek,AS_USER},
1006 /* 0x13 */ { "SMBlockread",reply_lockread,AS_USER},
1007 /* 0x14 */ { "SMBwriteunlock",reply_writeunlock,AS_USER},
1008 /* 0x15 */ { NULL, NULL, 0 },
1009 /* 0x16 */ { NULL, NULL, 0 },
1010 /* 0x17 */ { NULL, NULL, 0 },
1011 /* 0x18 */ { NULL, NULL, 0 },
1012 /* 0x19 */ { NULL, NULL, 0 },
1013 /* 0x1a */ { "SMBreadbraw",reply_readbraw,AS_USER},
1014 /* 0x1b */ { "SMBreadBmpx",reply_readbmpx,AS_USER},
1015 /* 0x1c */ { "SMBreadBs",reply_readbs,AS_USER },
1016 /* 0x1d */ { "SMBwritebraw",reply_writebraw,AS_USER},
1017 /* 0x1e */ { "SMBwriteBmpx",reply_writebmpx,AS_USER},
1018 /* 0x1f */ { "SMBwriteBs",reply_writebs,AS_USER},
1019 /* 0x20 */ { "SMBwritec", NULL,0},
1020 /* 0x21 */ { NULL, NULL, 0 },
1021 /* 0x22 */ { "SMBsetattrE",reply_setattrE,AS_USER | NEED_WRITE },
1022 /* 0x23 */ { "SMBgetattrE",reply_getattrE,AS_USER },
1023 /* 0x24 */ { "SMBlockingX",reply_lockingX,AS_USER },
1024 /* 0x25 */ { "SMBtrans",reply_trans,AS_USER | CAN_IPC },
1025 /* 0x26 */ { "SMBtranss",reply_transs,AS_USER | CAN_IPC},
1026 /* 0x27 */ { "SMBioctl",reply_ioctl,0},
1027 /* 0x28 */ { "SMBioctls", NULL,AS_USER},
1028 /* 0x29 */ { "SMBcopy",reply_copy,AS_USER | NEED_WRITE },
1029 /* 0x2a */ { "SMBmove", NULL,AS_USER | NEED_WRITE },
1030 /* 0x2b */ { "SMBecho",reply_echo,0},
1031 /* 0x2c */ { "SMBwriteclose",reply_writeclose,AS_USER},
1032 /* 0x2d */ { "SMBopenX",reply_open_and_X,AS_USER | CAN_IPC },
1033 /* 0x2e */ { "SMBreadX",reply_read_and_X,AS_USER | CAN_IPC },
1034 /* 0x2f */ { "SMBwriteX",reply_write_and_X,AS_USER | CAN_IPC },
1035 /* 0x30 */ { NULL, NULL, 0 },
1036 /* 0x31 */ { NULL, NULL, 0 },
1037 /* 0x32 */ { "SMBtrans2",reply_trans2, AS_USER | CAN_IPC },
1038 /* 0x33 */ { "SMBtranss2",reply_transs2, AS_USER},
1039 /* 0x34 */ { "SMBfindclose",reply_findclose,AS_USER},
1040 /* 0x35 */ { "SMBfindnclose",reply_findnclose,AS_USER},
1041 /* 0x36 */ { NULL, NULL, 0 },
1042 /* 0x37 */ { NULL, NULL, 0 },
1043 /* 0x38 */ { NULL, NULL, 0 },
1044 /* 0x39 */ { NULL, NULL, 0 },
1045 /* 0x3a */ { NULL, NULL, 0 },
1046 /* 0x3b */ { NULL, NULL, 0 },
1047 /* 0x3c */ { NULL, NULL, 0 },
1048 /* 0x3d */ { NULL, NULL, 0 },
1049 /* 0x3e */ { NULL, NULL, 0 },
1050 /* 0x3f */ { NULL, NULL, 0 },
1051 /* 0x40 */ { NULL, NULL, 0 },
1052 /* 0x41 */ { NULL, NULL, 0 },
1053 /* 0x42 */ { NULL, NULL, 0 },
1054 /* 0x43 */ { NULL, NULL, 0 },
1055 /* 0x44 */ { NULL, NULL, 0 },
1056 /* 0x45 */ { NULL, NULL, 0 },
1057 /* 0x46 */ { NULL, NULL, 0 },
1058 /* 0x47 */ { NULL, NULL, 0 },
1059 /* 0x48 */ { NULL, NULL, 0 },
1060 /* 0x49 */ { NULL, NULL, 0 },
1061 /* 0x4a */ { NULL, NULL, 0 },
1062 /* 0x4b */ { NULL, NULL, 0 },
1063 /* 0x4c */ { NULL, NULL, 0 },
1064 /* 0x4d */ { NULL, NULL, 0 },
1065 /* 0x4e */ { NULL, NULL, 0 },
1066 /* 0x4f */ { NULL, NULL, 0 },
1067 /* 0x50 */ { NULL, NULL, 0 },
1068 /* 0x51 */ { NULL, NULL, 0 },
1069 /* 0x52 */ { NULL, NULL, 0 },
1070 /* 0x53 */ { NULL, NULL, 0 },
1071 /* 0x54 */ { NULL, NULL, 0 },
1072 /* 0x55 */ { NULL, NULL, 0 },
1073 /* 0x56 */ { NULL, NULL, 0 },
1074 /* 0x57 */ { NULL, NULL, 0 },
1075 /* 0x58 */ { NULL, NULL, 0 },
1076 /* 0x59 */ { NULL, NULL, 0 },
1077 /* 0x5a */ { NULL, NULL, 0 },
1078 /* 0x5b */ { NULL, NULL, 0 },
1079 /* 0x5c */ { NULL, NULL, 0 },
1080 /* 0x5d */ { NULL, NULL, 0 },
1081 /* 0x5e */ { NULL, NULL, 0 },
1082 /* 0x5f */ { NULL, NULL, 0 },
1083 /* 0x60 */ { NULL, NULL, 0 },
1084 /* 0x61 */ { NULL, NULL, 0 },
1085 /* 0x62 */ { NULL, NULL, 0 },
1086 /* 0x63 */ { NULL, NULL, 0 },
1087 /* 0x64 */ { NULL, NULL, 0 },
1088 /* 0x65 */ { NULL, NULL, 0 },
1089 /* 0x66 */ { NULL, NULL, 0 },
1090 /* 0x67 */ { NULL, NULL, 0 },
1091 /* 0x68 */ { NULL, NULL, 0 },
1092 /* 0x69 */ { NULL, NULL, 0 },
1093 /* 0x6a */ { NULL, NULL, 0 },
1094 /* 0x6b */ { NULL, NULL, 0 },
1095 /* 0x6c */ { NULL, NULL, 0 },
1096 /* 0x6d */ { NULL, NULL, 0 },
1097 /* 0x6e */ { NULL, NULL, 0 },
1098 /* 0x6f */ { NULL, NULL, 0 },
1099 /* 0x70 */ { "SMBtcon",reply_tcon,0},
1100 /* 0x71 */ { "SMBtdis",reply_tdis,DO_CHDIR},
1101 /* 0x72 */ { "SMBnegprot",reply_negprot,0},
1102 /* 0x73 */ { "SMBsesssetupX",reply_sesssetup_and_X,0},
1103 /* 0x74 */ { "SMBulogoffX",reply_ulogoffX, 0}, /* ulogoff doesn't give a valid TID */
1104 /* 0x75 */ { "SMBtconX",reply_tcon_and_X,0},
1105 /* 0x76 */ { NULL, NULL, 0 },
1106 /* 0x77 */ { NULL, NULL, 0 },
1107 /* 0x78 */ { NULL, NULL, 0 },
1108 /* 0x79 */ { NULL, NULL, 0 },
1109 /* 0x7a */ { NULL, NULL, 0 },
1110 /* 0x7b */ { NULL, NULL, 0 },
1111 /* 0x7c */ { NULL, NULL, 0 },
1112 /* 0x7d */ { NULL, NULL, 0 },
1113 /* 0x7e */ { NULL, NULL, 0 },
1114 /* 0x7f */ { NULL, NULL, 0 },
1115 /* 0x80 */ { "SMBdskattr",reply_dskattr,AS_USER},
1116 /* 0x81 */ { "SMBsearch",reply_search,AS_USER},
1117 /* 0x82 */ { "SMBffirst",reply_search,AS_USER},
1118 /* 0x83 */ { "SMBfunique",reply_search,AS_USER},
1119 /* 0x84 */ { "SMBfclose",reply_fclose,AS_USER},
1120 /* 0x85 */ { NULL, NULL, 0 },
1121 /* 0x86 */ { NULL, NULL, 0 },
1122 /* 0x87 */ { NULL, NULL, 0 },
1123 /* 0x88 */ { NULL, NULL, 0 },
1124 /* 0x89 */ { NULL, NULL, 0 },
1125 /* 0x8a */ { NULL, NULL, 0 },
1126 /* 0x8b */ { NULL, NULL, 0 },
1127 /* 0x8c */ { NULL, NULL, 0 },
1128 /* 0x8d */ { NULL, NULL, 0 },
1129 /* 0x8e */ { NULL, NULL, 0 },
1130 /* 0x8f */ { NULL, NULL, 0 },
1131 /* 0x90 */ { NULL, NULL, 0 },
1132 /* 0x91 */ { NULL, NULL, 0 },
1133 /* 0x92 */ { NULL, NULL, 0 },
1134 /* 0x93 */ { NULL, NULL, 0 },
1135 /* 0x94 */ { NULL, NULL, 0 },
1136 /* 0x95 */ { NULL, NULL, 0 },
1137 /* 0x96 */ { NULL, NULL, 0 },
1138 /* 0x97 */ { NULL, NULL, 0 },
1139 /* 0x98 */ { NULL, NULL, 0 },
1140 /* 0x99 */ { NULL, NULL, 0 },
1141 /* 0x9a */ { NULL, NULL, 0 },
1142 /* 0x9b */ { NULL, NULL, 0 },
1143 /* 0x9c */ { NULL, NULL, 0 },
1144 /* 0x9d */ { NULL, NULL, 0 },
1145 /* 0x9e */ { NULL, NULL, 0 },
1146 /* 0x9f */ { NULL, NULL, 0 },
1147 /* 0xa0 */ { "SMBnttrans",reply_nttrans, AS_USER | CAN_IPC },
1148 /* 0xa1 */ { "SMBnttranss",reply_nttranss, AS_USER | CAN_IPC },
1149 /* 0xa2 */ { "SMBntcreateX",reply_ntcreate_and_X, AS_USER | CAN_IPC },
1150 /* 0xa3 */ { NULL, NULL, 0 },
1151 /* 0xa4 */ { "SMBntcancel",reply_ntcancel, 0 },
1152 /* 0xa5 */ { "SMBntrename",reply_ntrename, AS_USER | NEED_WRITE },
1153 /* 0xa6 */ { NULL, NULL, 0 },
1154 /* 0xa7 */ { NULL, NULL, 0 },
1155 /* 0xa8 */ { NULL, NULL, 0 },
1156 /* 0xa9 */ { NULL, NULL, 0 },
1157 /* 0xaa */ { NULL, NULL, 0 },
1158 /* 0xab */ { NULL, NULL, 0 },
1159 /* 0xac */ { NULL, NULL, 0 },
1160 /* 0xad */ { NULL, NULL, 0 },
1161 /* 0xae */ { NULL, NULL, 0 },
1162 /* 0xaf */ { NULL, NULL, 0 },
1163 /* 0xb0 */ { NULL, NULL, 0 },
1164 /* 0xb1 */ { NULL, NULL, 0 },
1165 /* 0xb2 */ { NULL, NULL, 0 },
1166 /* 0xb3 */ { NULL, NULL, 0 },
1167 /* 0xb4 */ { NULL, NULL, 0 },
1168 /* 0xb5 */ { NULL, NULL, 0 },
1169 /* 0xb6 */ { NULL, NULL, 0 },
1170 /* 0xb7 */ { NULL, NULL, 0 },
1171 /* 0xb8 */ { NULL, NULL, 0 },
1172 /* 0xb9 */ { NULL, NULL, 0 },
1173 /* 0xba */ { NULL, NULL, 0 },
1174 /* 0xbb */ { NULL, NULL, 0 },
1175 /* 0xbc */ { NULL, NULL, 0 },
1176 /* 0xbd */ { NULL, NULL, 0 },
1177 /* 0xbe */ { NULL, NULL, 0 },
1178 /* 0xbf */ { NULL, NULL, 0 },
1179 /* 0xc0 */ { "SMBsplopen",reply_printopen,AS_USER},
1180 /* 0xc1 */ { "SMBsplwr",reply_printwrite,AS_USER},
1181 /* 0xc2 */ { "SMBsplclose",reply_printclose,AS_USER},
1182 /* 0xc3 */ { "SMBsplretq",reply_printqueue,AS_USER},
1183 /* 0xc4 */ { NULL, NULL, 0 },
1184 /* 0xc5 */ { NULL, NULL, 0 },
1185 /* 0xc6 */ { NULL, NULL, 0 },
1186 /* 0xc7 */ { NULL, NULL, 0 },
1187 /* 0xc8 */ { NULL, NULL, 0 },
1188 /* 0xc9 */ { NULL, NULL, 0 },
1189 /* 0xca */ { NULL, NULL, 0 },
1190 /* 0xcb */ { NULL, NULL, 0 },
1191 /* 0xcc */ { NULL, NULL, 0 },
1192 /* 0xcd */ { NULL, NULL, 0 },
1193 /* 0xce */ { NULL, NULL, 0 },
1194 /* 0xcf */ { NULL, NULL, 0 },
1195 /* 0xd0 */ { "SMBsends",reply_sends,AS_GUEST},
1196 /* 0xd1 */ { "SMBsendb", NULL,AS_GUEST},
1197 /* 0xd2 */ { "SMBfwdname", NULL,AS_GUEST},
1198 /* 0xd3 */ { "SMBcancelf", NULL,AS_GUEST},
1199 /* 0xd4 */ { "SMBgetmac", NULL,AS_GUEST},
1200 /* 0xd5 */ { "SMBsendstrt",reply_sendstrt,AS_GUEST},
1201 /* 0xd6 */ { "SMBsendend",reply_sendend,AS_GUEST},
1202 /* 0xd7 */ { "SMBsendtxt",reply_sendtxt,AS_GUEST},
1203 /* 0xd8 */ { NULL, NULL, 0 },
1204 /* 0xd9 */ { NULL, NULL, 0 },
1205 /* 0xda */ { NULL, NULL, 0 },
1206 /* 0xdb */ { NULL, NULL, 0 },
1207 /* 0xdc */ { NULL, NULL, 0 },
1208 /* 0xdd */ { NULL, NULL, 0 },
1209 /* 0xde */ { NULL, NULL, 0 },
1210 /* 0xdf */ { NULL, NULL, 0 },
1211 /* 0xe0 */ { NULL, NULL, 0 },
1212 /* 0xe1 */ { NULL, NULL, 0 },
1213 /* 0xe2 */ { NULL, NULL, 0 },
1214 /* 0xe3 */ { NULL, NULL, 0 },
1215 /* 0xe4 */ { NULL, NULL, 0 },
1216 /* 0xe5 */ { NULL, NULL, 0 },
1217 /* 0xe6 */ { NULL, NULL, 0 },
1218 /* 0xe7 */ { NULL, NULL, 0 },
1219 /* 0xe8 */ { NULL, NULL, 0 },
1220 /* 0xe9 */ { NULL, NULL, 0 },
1221 /* 0xea */ { NULL, NULL, 0 },
1222 /* 0xeb */ { NULL, NULL, 0 },
1223 /* 0xec */ { NULL, NULL, 0 },
1224 /* 0xed */ { NULL, NULL, 0 },
1225 /* 0xee */ { NULL, NULL, 0 },
1226 /* 0xef */ { NULL, NULL, 0 },
1227 /* 0xf0 */ { NULL, NULL, 0 },
1228 /* 0xf1 */ { NULL, NULL, 0 },
1229 /* 0xf2 */ { NULL, NULL, 0 },
1230 /* 0xf3 */ { NULL, NULL, 0 },
1231 /* 0xf4 */ { NULL, NULL, 0 },
1232 /* 0xf5 */ { NULL, NULL, 0 },
1233 /* 0xf6 */ { NULL, NULL, 0 },
1234 /* 0xf7 */ { NULL, NULL, 0 },
1235 /* 0xf8 */ { NULL, NULL, 0 },
1236 /* 0xf9 */ { NULL, NULL, 0 },
1237 /* 0xfa */ { NULL, NULL, 0 },
1238 /* 0xfb */ { NULL, NULL, 0 },
1239 /* 0xfc */ { NULL, NULL, 0 },
1240 /* 0xfd */ { NULL, NULL, 0 },
1241 /* 0xfe */ { NULL, NULL, 0 },
1242 /* 0xff */ { NULL, NULL, 0 }
1243
1244 };
1245
1246 /*******************************************************************
1247  allocate and initialize a reply packet
1248 ********************************************************************/
1249
1250 bool create_outbuf(TALLOC_CTX *mem_ctx, const char *inbuf, char **outbuf,
1251                    uint8_t num_words, uint32_t num_bytes)
1252 {
1253         /*
1254          * Protect against integer wrap
1255          */
1256         if ((num_bytes > 0xffffff)
1257             || ((num_bytes + smb_size + num_words*2) > 0xffffff)) {
1258                 char *msg;
1259                 if (asprintf(&msg, "num_bytes too large: %u",
1260                              (unsigned)num_bytes) == -1) {
1261                         msg = CONST_DISCARD(char *, "num_bytes too large");
1262                 }
1263                 smb_panic(msg);
1264         }
1265
1266         *outbuf = TALLOC_ARRAY(mem_ctx, char,
1267                                smb_size + num_words*2 + num_bytes);
1268         if (*outbuf == NULL) {
1269                 return false;
1270         }
1271
1272         construct_reply_common(inbuf, *outbuf);
1273         srv_set_message(*outbuf, num_words, num_bytes, false);
1274         /*
1275          * Zero out the word area, the caller has to take care of the bcc area
1276          * himself
1277          */
1278         if (num_words != 0) {
1279                 memset(*outbuf + smb_vwv0, 0, num_words*2);
1280         }
1281
1282         return true;
1283 }
1284
1285 void reply_outbuf(struct smb_request *req, uint8 num_words, uint32 num_bytes)
1286 {
1287         char *outbuf;
1288         if (!create_outbuf(req, (char *)req->inbuf, &outbuf, num_words,
1289                            num_bytes)) {
1290                 smb_panic("could not allocate output buffer\n");
1291         }
1292         req->outbuf = (uint8_t *)outbuf;
1293 }
1294
1295
1296 /*******************************************************************
1297  Dump a packet to a file.
1298 ********************************************************************/
1299
1300 static void smb_dump(const char *name, int type, const char *data, ssize_t len)
1301 {
1302         int fd, i;
1303         char *fname = NULL;
1304         if (DEBUGLEVEL < 50) {
1305                 return;
1306         }
1307
1308         if (len < 4) len = smb_len(data)+4;
1309         for (i=1;i<100;i++) {
1310                 if (asprintf(&fname, "/tmp/%s.%d.%s", name, i,
1311                              type ? "req" : "resp") == -1) {
1312                         return;
1313                 }
1314                 fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0644);
1315                 if (fd != -1 || errno != EEXIST) break;
1316         }
1317         if (fd != -1) {
1318                 ssize_t ret = write(fd, data, len);
1319                 if (ret != len)
1320                         DEBUG(0,("smb_dump: problem: write returned %d\n", (int)ret ));
1321                 close(fd);
1322                 DEBUG(0,("created %s len %lu\n", fname, (unsigned long)len));
1323         }
1324         SAFE_FREE(fname);
1325 }
1326
1327 /****************************************************************************
1328  Prepare everything for calling the actual request function, and potentially
1329  call the request function via the "new" interface.
1330
1331  Return False if the "legacy" function needs to be called, everything is
1332  prepared.
1333
1334  Return True if we're done.
1335
1336  I know this API sucks, but it is the one with the least code change I could
1337  find.
1338 ****************************************************************************/
1339
1340 static connection_struct *switch_message(uint8 type, struct smb_request *req, int size)
1341 {
1342         int flags;
1343         uint16 session_tag;
1344         connection_struct *conn = NULL;
1345
1346         static uint16 last_session_tag = UID_FIELD_INVALID;
1347
1348         errno = 0;
1349
1350         /* Make sure this is an SMB packet. smb_size contains NetBIOS header
1351          * so subtract 4 from it. */
1352         if (!valid_smb_header(req->inbuf)
1353             || (size < (smb_size - 4))) {
1354                 DEBUG(2,("Non-SMB packet of length %d. Terminating server\n",
1355                          smb_len(req->inbuf)));
1356                 exit_server_cleanly("Non-SMB packet");
1357         }
1358
1359         if (smb_messages[type].fn == NULL) {
1360                 DEBUG(0,("Unknown message type %d!\n",type));
1361                 smb_dump("Unknown", 1, (char *)req->inbuf, size);
1362                 reply_unknown_new(req, type);
1363                 return NULL;
1364         }
1365
1366         flags = smb_messages[type].flags;
1367
1368         /* In share mode security we must ignore the vuid. */
1369         session_tag = (lp_security() == SEC_SHARE)
1370                 ? UID_FIELD_INVALID : req->vuid;
1371         conn = req->conn;
1372
1373         DEBUG(3,("switch message %s (pid %d) conn 0x%lx\n", smb_fn_name(type),
1374                  (int)sys_getpid(), (unsigned long)conn));
1375
1376         smb_dump(smb_fn_name(type), 1, (char *)req->inbuf, size);
1377
1378         /* Ensure this value is replaced in the incoming packet. */
1379         SSVAL(req->inbuf,smb_uid,session_tag);
1380
1381         /*
1382          * Ensure the correct username is in current_user_info.  This is a
1383          * really ugly bugfix for problems with multiple session_setup_and_X's
1384          * being done and allowing %U and %G substitutions to work correctly.
1385          * There is a reason this code is done here, don't move it unless you
1386          * know what you're doing... :-).
1387          * JRA.
1388          */
1389
1390         if (session_tag != last_session_tag) {
1391                 user_struct *vuser = NULL;
1392
1393                 last_session_tag = session_tag;
1394                 if(session_tag != UID_FIELD_INVALID) {
1395                         vuser = get_valid_user_struct(session_tag);
1396                         if (vuser) {
1397                                 set_current_user_info(
1398                                         vuser->server_info->sanitized_username,
1399                                         vuser->server_info->unix_name,
1400                                         pdb_get_fullname(vuser->server_info
1401                                                          ->sam_account),
1402                                         pdb_get_domain(vuser->server_info
1403                                                        ->sam_account));
1404                         }
1405                 }
1406         }
1407
1408         /* Does this call need to be run as the connected user? */
1409         if (flags & AS_USER) {
1410
1411                 /* Does this call need a valid tree connection? */
1412                 if (!conn) {
1413                         /*
1414                          * Amazingly, the error code depends on the command
1415                          * (from Samba4).
1416                          */
1417                         if (type == SMBntcreateX) {
1418                                 reply_nterror(req, NT_STATUS_INVALID_HANDLE);
1419                         } else {
1420                                 reply_doserror(req, ERRSRV, ERRinvnid);
1421                         }
1422                         return NULL;
1423                 }
1424
1425                 if (!change_to_user(conn,session_tag)) {
1426                         reply_nterror(req, NT_STATUS_DOS(ERRSRV, ERRbaduid));
1427                         remove_deferred_open_smb_message(req->mid);
1428                         return conn;
1429                 }
1430
1431                 /* All NEED_WRITE and CAN_IPC flags must also have AS_USER. */
1432
1433                 /* Does it need write permission? */
1434                 if ((flags & NEED_WRITE) && !CAN_WRITE(conn)) {
1435                         reply_nterror(req, NT_STATUS_MEDIA_WRITE_PROTECTED);
1436                         return conn;
1437                 }
1438
1439                 /* IPC services are limited */
1440                 if (IS_IPC(conn) && !(flags & CAN_IPC)) {
1441                         reply_doserror(req, ERRSRV,ERRaccess);
1442                         return conn;
1443                 }
1444         } else {
1445                 /* This call needs to be run as root */
1446                 change_to_root_user();
1447         }
1448
1449         /* load service specific parameters */
1450         if (conn) {
1451                 if (req->encrypted) {
1452                         conn->encrypted_tid = true;
1453                         /* encrypted required from now on. */
1454                         conn->encrypt_level = Required;
1455                 } else if (ENCRYPTION_REQUIRED(conn)) {
1456                         if (req->cmd != SMBtrans2 && req->cmd != SMBtranss2) {
1457                                 exit_server_cleanly("encryption required "
1458                                         "on connection");
1459                                 return conn;
1460                         }
1461                 }
1462
1463                 if (!set_current_service(conn,SVAL(req->inbuf,smb_flg),
1464                                          (flags & (AS_USER|DO_CHDIR)
1465                                           ?True:False))) {
1466                         reply_doserror(req, ERRSRV, ERRaccess);
1467                         return conn;
1468                 }
1469                 conn->num_smb_operations++;
1470         }
1471
1472         /* does this protocol need to be run as guest? */
1473         if ((flags & AS_GUEST)
1474             && (!change_to_guest() ||
1475                 !check_access(smbd_server_fd(), lp_hostsallow(-1),
1476                               lp_hostsdeny(-1)))) {
1477                 reply_doserror(req, ERRSRV, ERRaccess);
1478                 return conn;
1479         }
1480
1481         smb_messages[type].fn(req);
1482         return req->conn;
1483 }
1484
1485 /****************************************************************************
1486  Construct a reply to the incoming packet.
1487 ****************************************************************************/
1488
1489 static void construct_reply(char *inbuf, int size, size_t unread_bytes, bool encrypted)
1490 {
1491         connection_struct *conn;
1492         struct smb_request *req;
1493
1494         chain_size = 0;
1495
1496         if (!(req = talloc(talloc_tos(), struct smb_request))) {
1497                 smb_panic("could not allocate smb_request");
1498         }
1499         init_smb_request(req, (uint8 *)inbuf, unread_bytes, encrypted);
1500
1501         conn = switch_message(req->cmd, req, size);
1502
1503         if (req->unread_bytes) {
1504                 /* writeX failed. drain socket. */
1505                 if (drain_socket(smbd_server_fd(), req->unread_bytes) !=
1506                                 req->unread_bytes) {
1507                         smb_panic("failed to drain pending bytes");
1508                 }
1509                 req->unread_bytes = 0;
1510         }
1511
1512         if (req->outbuf == NULL) {
1513                 return;
1514         }
1515
1516         if (CVAL(req->outbuf,0) == 0) {
1517                 show_msg((char *)req->outbuf);
1518         }
1519
1520         if (!srv_send_smb(smbd_server_fd(),
1521                         (char *)req->outbuf,
1522                         IS_CONN_ENCRYPTED(conn)||req->encrypted)) {
1523                 exit_server_cleanly("construct_reply: srv_send_smb failed.");
1524         }
1525
1526         TALLOC_FREE(req);
1527
1528         return;
1529 }
1530
1531 /****************************************************************************
1532  Process an smb from the client
1533 ****************************************************************************/
1534
1535 static void process_smb(char *inbuf, size_t nread, size_t unread_bytes, bool encrypted)
1536 {
1537         static int trans_num;
1538         int msg_type = CVAL(inbuf,0);
1539
1540         DO_PROFILE_INC(smb_count);
1541
1542         DEBUG( 6, ( "got message type 0x%x of len 0x%x\n", msg_type,
1543                     smb_len(inbuf) ) );
1544         DEBUG( 3, ( "Transaction %d of length %d (%u toread)\n", trans_num,
1545                                 (int)nread,
1546                                 (unsigned int)unread_bytes ));
1547
1548         if (msg_type != 0) {
1549                 /*
1550                  * NetBIOS session request, keepalive, etc.
1551                  */
1552                 reply_special(inbuf);
1553                 return;
1554         }
1555
1556         show_msg(inbuf);
1557
1558         construct_reply(inbuf,nread,unread_bytes,encrypted);
1559
1560         trans_num++;
1561 }
1562
1563 /****************************************************************************
1564  Return a string containing the function name of a SMB command.
1565 ****************************************************************************/
1566
1567 const char *smb_fn_name(int type)
1568 {
1569         const char *unknown_name = "SMBunknown";
1570
1571         if (smb_messages[type].name == NULL)
1572                 return(unknown_name);
1573
1574         return(smb_messages[type].name);
1575 }
1576
1577 /****************************************************************************
1578  Helper functions for contruct_reply.
1579 ****************************************************************************/
1580
1581 static uint32 common_flags2 = FLAGS2_LONG_PATH_COMPONENTS|FLAGS2_32_BIT_ERROR_CODES;
1582
1583 void add_to_common_flags2(uint32 v)
1584 {
1585         common_flags2 |= v;
1586 }
1587
1588 void remove_from_common_flags2(uint32 v)
1589 {
1590         common_flags2 &= ~v;
1591 }
1592
1593 void construct_reply_common(const char *inbuf, char *outbuf)
1594 {
1595         srv_set_message(outbuf,0,0,false);
1596
1597         SCVAL(outbuf,smb_com,CVAL(inbuf,smb_com));
1598         SIVAL(outbuf,smb_rcls,0);
1599         SCVAL(outbuf,smb_flg, FLAG_REPLY | (CVAL(inbuf,smb_flg) & FLAG_CASELESS_PATHNAMES));
1600         SSVAL(outbuf,smb_flg2,
1601                 (SVAL(inbuf,smb_flg2) & FLAGS2_UNICODE_STRINGS) |
1602                 common_flags2);
1603         memset(outbuf+smb_pidhigh,'\0',(smb_tid-smb_pidhigh));
1604
1605         SSVAL(outbuf,smb_tid,SVAL(inbuf,smb_tid));
1606         SSVAL(outbuf,smb_pid,SVAL(inbuf,smb_pid));
1607         SSVAL(outbuf,smb_uid,SVAL(inbuf,smb_uid));
1608         SSVAL(outbuf,smb_mid,SVAL(inbuf,smb_mid));
1609 }
1610
1611 void construct_reply_common_req(struct smb_request *req, char *outbuf)
1612 {
1613         return construct_reply_common((char *)req->inbuf, outbuf);
1614 }
1615
1616 /****************************************************************************
1617  Construct a chained reply and add it to the already made reply
1618 ****************************************************************************/
1619
1620 void chain_reply(struct smb_request *req)
1621 {
1622         static char *orig_inbuf;
1623
1624         /*
1625          * Dirty little const_discard: We mess with req->inbuf, which is
1626          * declared as const. If maybe at some point this routine gets
1627          * rewritten, this const_discard could go away.
1628          */
1629         char *inbuf = CONST_DISCARD(char *, req->inbuf);
1630         int size = smb_len(req->inbuf)+4;
1631
1632         int smb_com1, smb_com2 = CVAL(inbuf,smb_vwv0);
1633         unsigned smb_off2 = SVAL(inbuf,smb_vwv1);
1634         char *inbuf2;
1635         int outsize2;
1636         int new_size;
1637         char inbuf_saved[smb_wct];
1638         char *outbuf = (char *)req->outbuf;
1639         size_t outsize = smb_len(outbuf) + 4;
1640         size_t outsize_padded;
1641         size_t padding;
1642         size_t ofs, to_move;
1643
1644         struct smb_request *req2;
1645         size_t caller_outputlen;
1646         char *caller_output;
1647
1648         /* Maybe its not chained, or it's an error packet. */
1649         if (smb_com2 == 0xFF || SVAL(outbuf,smb_rcls) != 0) {
1650                 SCVAL(outbuf,smb_vwv0,0xFF);
1651                 return;
1652         }
1653
1654         if (chain_size == 0) {
1655                 /* this is the first part of the chain */
1656                 orig_inbuf = inbuf;
1657         }
1658
1659         /*
1660          * We need to save the output the caller added to the chain so that we
1661          * can splice it into the final output buffer later.
1662          */
1663
1664         caller_outputlen = outsize - smb_wct;
1665
1666         caller_output = (char *)memdup(outbuf + smb_wct, caller_outputlen);
1667
1668         if (caller_output == NULL) {
1669                 /* TODO: NT_STATUS_NO_MEMORY */
1670                 smb_panic("could not dup outbuf");
1671         }
1672
1673         /*
1674          * The original Win95 redirector dies on a reply to
1675          * a lockingX and read chain unless the chain reply is
1676          * 4 byte aligned. JRA.
1677          */
1678
1679         outsize_padded = (outsize + 3) & ~3;
1680         padding = outsize_padded - outsize;
1681
1682         /*
1683          * remember how much the caller added to the chain, only counting
1684          * stuff after the parameter words
1685          */
1686         chain_size += (outsize_padded - smb_wct);
1687
1688         /*
1689          * work out pointers into the original packets. The
1690          * headers on these need to be filled in
1691          */
1692         inbuf2 = orig_inbuf + smb_off2 + 4 - smb_wct;
1693
1694         /* remember the original command type */
1695         smb_com1 = CVAL(orig_inbuf,smb_com);
1696
1697         /* save the data which will be overwritten by the new headers */
1698         memcpy(inbuf_saved,inbuf2,smb_wct);
1699
1700         /* give the new packet the same header as the last part of the SMB */
1701         memmove(inbuf2,inbuf,smb_wct);
1702
1703         /* create the in buffer */
1704         SCVAL(inbuf2,smb_com,smb_com2);
1705
1706         /* work out the new size for the in buffer. */
1707         new_size = size - (inbuf2 - inbuf);
1708         if (new_size < 0) {
1709                 DEBUG(0,("chain_reply: chain packet size incorrect "
1710                          "(orig size = %d, offset = %d)\n",
1711                          size, (int)(inbuf2 - inbuf) ));
1712                 exit_server_cleanly("Bad chained packet");
1713                 return;
1714         }
1715
1716         /* And set it in the header. */
1717         smb_setlen(inbuf2, new_size - 4);
1718
1719         DEBUG(3,("Chained message\n"));
1720         show_msg(inbuf2);
1721
1722         if (!(req2 = talloc(talloc_tos(), struct smb_request))) {
1723                 smb_panic("could not allocate smb_request");
1724         }
1725         init_smb_request(req2, (uint8 *)inbuf2,0, req->encrypted);
1726         req2->chain_fsp = req->chain_fsp;
1727
1728         /* process the request */
1729         switch_message(smb_com2, req2, new_size);
1730
1731         /*
1732          * We don't accept deferred operations in chained requests.
1733          */
1734         SMB_ASSERT(req2->outbuf != NULL);
1735         outsize2 = smb_len(req2->outbuf)+4;
1736
1737         /*
1738          * Move away the new command output so that caller_output fits in,
1739          * copy in the caller_output saved above.
1740          */
1741
1742         SMB_ASSERT(outsize_padded >= smb_wct);
1743
1744         /*
1745          * "ofs" is the space we need for caller_output. Equal to
1746          * caller_outputlen plus the padding.
1747          */
1748
1749         ofs = outsize_padded - smb_wct;
1750
1751         /*
1752          * "to_move" is the amount of bytes the secondary routine gave us
1753          */
1754
1755         to_move = outsize2 - smb_wct;
1756
1757         if (to_move + ofs + smb_wct + chain_size > max_send) {
1758                 smb_panic("replies too large -- would have to cut");
1759         }
1760
1761         /*
1762          * In the "new" API "outbuf" is allocated via reply_outbuf, just for
1763          * the first request in the chain. So we have to re-allocate it. In
1764          * the "old" API the only outbuf ever used is the global OutBuffer
1765          * which is always large enough.
1766          */
1767
1768         outbuf = TALLOC_REALLOC_ARRAY(NULL, outbuf, char,
1769                                       to_move + ofs + smb_wct);
1770         if (outbuf == NULL) {
1771                 smb_panic("could not realloc outbuf");
1772         }
1773
1774         req->outbuf = (uint8 *)outbuf;
1775
1776         memmove(outbuf + smb_wct + ofs, req2->outbuf + smb_wct, to_move);
1777         memcpy(outbuf + smb_wct, caller_output, caller_outputlen);
1778
1779         /*
1780          * copy the new reply header over the old one but preserve the smb_com
1781          * field
1782          */
1783         memmove(outbuf, req2->outbuf, smb_wct);
1784         SCVAL(outbuf, smb_com, smb_com1);
1785
1786         /*
1787          * We've just copied in the whole "wct" area from the secondary
1788          * function. Fix up the chaining: com2 and the offset need to be
1789          * readjusted.
1790          */
1791
1792         SCVAL(outbuf, smb_vwv0, smb_com2);
1793         SSVAL(outbuf, smb_vwv1, chain_size + smb_wct - 4);
1794
1795         if (padding != 0) {
1796
1797                 /*
1798                  * Due to padding we have some uninitialized bytes after the
1799                  * caller's output
1800                  */
1801
1802                 memset(outbuf + outsize, 0, padding);
1803         }
1804
1805         smb_setlen(outbuf, outsize2 + caller_outputlen + padding - 4);
1806
1807         /*
1808          * restore the saved data, being careful not to overwrite any data
1809          * from the reply header
1810          */
1811         memcpy(inbuf2,inbuf_saved,smb_wct);
1812
1813         SAFE_FREE(caller_output);
1814         TALLOC_FREE(req2);
1815
1816         /*
1817          * Reset the chain_size for our caller's offset calculations
1818          */
1819
1820         chain_size -= (outsize_padded - smb_wct);
1821
1822         return;
1823 }
1824
1825 /****************************************************************************
1826  Check if services need reloading.
1827 ****************************************************************************/
1828
1829 void check_reload(time_t t)
1830 {
1831         static pid_t mypid = 0;
1832         static time_t last_smb_conf_reload_time = 0;
1833         static time_t last_printer_reload_time = 0;
1834         time_t printcap_cache_time = (time_t)lp_printcap_cache_time();
1835
1836         if(last_smb_conf_reload_time == 0) {
1837                 last_smb_conf_reload_time = t;
1838                 /* Our printing subsystem might not be ready at smbd start up.
1839                    Then no printer is available till the first printers check
1840                    is performed.  A lower initial interval circumvents this. */
1841                 if ( printcap_cache_time > 60 )
1842                         last_printer_reload_time = t - printcap_cache_time + 60;
1843                 else
1844                         last_printer_reload_time = t;
1845         }
1846
1847         if (mypid != getpid()) { /* First time or fork happened meanwhile */
1848                 /* randomize over 60 second the printcap reload to avoid all
1849                  * process hitting cupsd at the same time */
1850                 int time_range = 60;
1851
1852                 last_printer_reload_time += random() % time_range;
1853                 mypid = getpid();
1854         }
1855
1856         if (reload_after_sighup || (t >= last_smb_conf_reload_time+SMBD_RELOAD_CHECK)) {
1857                 reload_services(True);
1858                 reload_after_sighup = False;
1859                 last_smb_conf_reload_time = t;
1860         }
1861
1862         /* 'printcap cache time = 0' disable the feature */
1863
1864         if ( printcap_cache_time != 0 )
1865         {
1866                 /* see if it's time to reload or if the clock has been set back */
1867
1868                 if ( (t >= last_printer_reload_time+printcap_cache_time)
1869                         || (t-last_printer_reload_time  < 0) )
1870                 {
1871                         DEBUG( 3,( "Printcap cache time expired.\n"));
1872                         reload_printers();
1873                         last_printer_reload_time = t;
1874                 }
1875         }
1876 }
1877
1878 /****************************************************************************
1879  Process commands from the client
1880 ****************************************************************************/
1881
1882 void smbd_process(void)
1883 {
1884         unsigned int num_smbs = 0;
1885         size_t unread_bytes = 0;
1886
1887         char addr[INET6_ADDRSTRLEN];
1888
1889         /*
1890          * Before the first packet, check the global hosts allow/ hosts deny
1891          * parameters before doing any parsing of packets passed to us by the
1892          * client. This prevents attacks on our parsing code from hosts not in
1893          * the hosts allow list.
1894          */
1895
1896         if (!check_access(smbd_server_fd(), lp_hostsallow(-1),
1897                           lp_hostsdeny(-1))) {
1898                 /*
1899                  * send a negative session response "not listening on calling
1900                  * name"
1901                  */
1902                 unsigned char buf[5] = {0x83, 0, 0, 1, 0x81};
1903                 DEBUG( 1, ("Connection denied from %s\n",
1904                            client_addr(get_client_fd(),addr,sizeof(addr)) ) );
1905                 (void)srv_send_smb(smbd_server_fd(),(char *)buf,false);
1906                 exit_server_cleanly("connection denied");
1907         }
1908
1909         max_recv = MIN(lp_maxxmit(),BUFFER_SIZE);
1910
1911         while (True) {
1912                 NTSTATUS status;
1913                 char *inbuf = NULL;
1914                 size_t inbuf_len = 0;
1915                 bool encrypted = false;
1916                 TALLOC_CTX *frame = talloc_stackframe_pool(8192);
1917
1918                 errno = 0;
1919
1920                 run_events(smbd_event_context(), 0, NULL, NULL);
1921
1922                 status = receive_message_or_smb(
1923                         talloc_tos(), &inbuf, &inbuf_len,
1924                         &unread_bytes, &encrypted);
1925
1926                 if (!NT_STATUS_IS_OK(status)) {
1927                         DEBUG(3, ("receive_message_or_smb failed: %s, "
1928                                   "exiting\n", nt_errstr(status)));
1929                         return;
1930                 }
1931
1932                 process_smb(inbuf, inbuf_len, unread_bytes, encrypted);
1933
1934                 TALLOC_FREE(inbuf);
1935
1936                 num_smbs++;
1937
1938                 /* The timeout_processing function isn't run nearly
1939                    often enough to implement 'max log size' without
1940                    overrunning the size of the file by many megabytes.
1941                    This is especially true if we are running at debug
1942                    level 10.  Checking every 50 SMBs is a nice
1943                    tradeoff of performance vs log file size overrun. */
1944
1945                 if ((num_smbs % 50) == 0 && need_to_check_log_size()) {
1946                         change_to_root_user();
1947                         check_log_size();
1948                 }
1949                 TALLOC_FREE(frame);
1950         }
1951 }