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