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 #include "smbd/globals.h"
  23
  24 extern bool global_machine_password_needs_changing;
  25
  26 static void construct_reply_common(struct smb_request *req, const char *inbuf,
  27                                    char *outbuf);
  28
  29 /* Accessor function for smb_read_error for smbd functions. */
  30
  31 /****************************************************************************
  32  Send an smb to a fd.
  33 ****************************************************************************/
  34
  35 bool srv_send_smb(int fd, char *buffer, bool do_encrypt)
  36 {
  37         size_t len;
  38         size_t nwritten=0;
  39         ssize_t ret;
  40         char *buf_out = buffer;
  41
  42         /* Sign the outgoing packet if required. */
  43         srv_calculate_sign_mac(buf_out);
  44
  45         if (do_encrypt) {
  46                 NTSTATUS status = srv_encrypt_buffer(buffer, &buf_out);
  47                 if (!NT_STATUS_IS_OK(status)) {
  48                         DEBUG(0, ("send_smb: SMB encryption failed "
  49                                 "on outgoing packet! Error %s\n",
  50                                 nt_errstr(status) ));
  51                         return false;
  52                 }
  53         }
  54
  55         len = smb_len(buf_out) + 4;
  56
  57         while (nwritten < len) {
  58                 ret = write_data(fd,buf_out+nwritten,len - nwritten);
  59                 if (ret <= 0) {
  60                         DEBUG(0,("Error writing %d bytes to client. %d. (%s)\n",
  61                                 (int)len,(int)ret, strerror(errno) ));
  62                         srv_free_enc_buffer(buf_out);
  63                         return false;
  64                 }
  65                 nwritten += ret;
  66         }
  67
  68         srv_free_enc_buffer(buf_out);
  69         return true;
  70 }
  71
  72 /*******************************************************************
  73  Setup the word count and byte count for a smb message.
  74 ********************************************************************/
  75
  76 int srv_set_message(char *buf,
  77                         int num_words,
  78                         int num_bytes,
  79                         bool zero)
  80 {
  81         if (zero && (num_words || num_bytes)) {
  82                 memset(buf + smb_size,'\0',num_words*2 + num_bytes);
  83         }
  84         SCVAL(buf,smb_wct,num_words);
  85         SSVAL(buf,smb_vwv + num_words*SIZEOFWORD,num_bytes);
  86         smb_setlen(buf,(smb_size + num_words*2 + num_bytes - 4));
  87         return (smb_size + num_words*2 + num_bytes);
  88 }
  89
  90 static bool valid_smb_header(const uint8_t *inbuf)
  91 {
  92         if (is_encrypted_packet(inbuf)) {
  93                 return true;
  94         }
  95         /*
  96          * This used to be (strncmp(smb_base(inbuf),"\377SMB",4) == 0)
  97          * but it just looks weird to call strncmp for this one.
  98          */
  99         return (IVAL(smb_base(inbuf), 0) == 0x424D53FF);
 100 }
 101
 102 /* Socket functions for smbd packet processing. */
 103
 104 static bool valid_packet_size(size_t len)
 105 {
 106         /*
 107          * A WRITEX with CAP_LARGE_WRITEX can be 64k worth of data plus 65 bytes
 108          * of header. Don't print the error if this fits.... JRA.
 109          */
 110
 111         if (len > (BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE)) {
 112                 DEBUG(0,("Invalid packet length! (%lu bytes).\n",
 113                                         (unsigned long)len));
 114                 return false;
 115         }
 116         return true;
 117 }
 118
 119 static NTSTATUS read_packet_remainder(int fd, char *buffer,
 120                                       unsigned int timeout, ssize_t len)
 121 {
 122         if (len <= 0) {
 123                 return NT_STATUS_OK;
 124         }
 125
 126         return read_socket_with_timeout(fd, buffer, len, len, timeout, NULL);
 127 }
 128
 129 /****************************************************************************
 130  Attempt a zerocopy writeX read. We know here that len > smb_size-4
 131 ****************************************************************************/
 132
 133 /*
 134  * Unfortunately, earlier versions of smbclient/libsmbclient
 135  * don't send this "standard" writeX header. I've fixed this
 136  * for 3.2 but we'll use the old method with earlier versions.
 137  * Windows and CIFSFS at least use this standard size. Not
 138  * sure about MacOSX.
 139  */
 140
 141 #define STANDARD_WRITE_AND_X_HEADER_SIZE (smb_size - 4 + /* basic header */ \
 142                                 (2*14) + /* word count (including bcc) */ \
 143                                 1 /* pad byte */)
 144
 145 static NTSTATUS receive_smb_raw_talloc_partial_read(TALLOC_CTX *mem_ctx,
 146                                                     const char lenbuf[4],
 147                                                     int fd, char **buffer,
 148                                                     unsigned int timeout,
 149                                                     size_t *p_unread,
 150                                                     size_t *len_ret)
 151 {
 152         /* Size of a WRITEX call (+4 byte len). */
 153         char writeX_header[4 + STANDARD_WRITE_AND_X_HEADER_SIZE];
 154         ssize_t len = smb_len_large(lenbuf); /* Could be a UNIX large writeX. */
 155         ssize_t toread;
 156         NTSTATUS status;
 157
 158         memcpy(writeX_header, lenbuf, 4);
 159
 160         status = read_socket_with_timeout(
 161                 fd, writeX_header + 4,
 162                 STANDARD_WRITE_AND_X_HEADER_SIZE,
 163                 STANDARD_WRITE_AND_X_HEADER_SIZE,
 164                 timeout, NULL);
 165
 166         if (!NT_STATUS_IS_OK(status)) {
 167                 return status;
 168         }
 169
 170         /*
 171          * Ok - now try and see if this is a possible
 172          * valid writeX call.
 173          */
 174
 175         if (is_valid_writeX_buffer((uint8_t *)writeX_header)) {
 176                 /*
 177                  * If the data offset is beyond what
 178                  * we've read, drain the extra bytes.
 179                  */
 180                 uint16_t doff = SVAL(writeX_header,smb_vwv11);
 181                 ssize_t newlen;
 182
 183                 if (doff > STANDARD_WRITE_AND_X_HEADER_SIZE) {
 184                         size_t drain = doff - STANDARD_WRITE_AND_X_HEADER_SIZE;
 185                         if (drain_socket(smbd_server_fd(), drain) != drain) {
 186                                 smb_panic("receive_smb_raw_talloc_partial_read:"
 187                                         " failed to drain pending bytes");
 188                         }
 189                 } else {
 190                         doff = STANDARD_WRITE_AND_X_HEADER_SIZE;
 191                 }
 192
 193                 /* Spoof down the length and null out the bcc. */
 194                 set_message_bcc(writeX_header, 0);
 195                 newlen = smb_len(writeX_header);
 196
 197                 /* Copy the header we've written. */
 198
 199                 *buffer = (char *)TALLOC_MEMDUP(mem_ctx,
 200                                 writeX_header,
 201                                 sizeof(writeX_header));
 202
 203                 if (*buffer == NULL) {
 204                         DEBUG(0, ("Could not allocate inbuf of length %d\n",
 205                                   (int)sizeof(writeX_header)));
 206                         return NT_STATUS_NO_MEMORY;
 207                 }
 208
 209                 /* Work out the remaining bytes. */
 210                 *p_unread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
 211                 *len_ret = newlen + 4;
 212                 return NT_STATUS_OK;
 213         }
 214
 215         if (!valid_packet_size(len)) {
 216                 return NT_STATUS_INVALID_PARAMETER;
 217         }
 218
 219         /*
 220          * Not a valid writeX call. Just do the standard
 221          * talloc and return.
 222          */
 223
 224         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
 225
 226         if (*buffer == NULL) {
 227                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
 228                           (int)len+4));
 229                 return NT_STATUS_NO_MEMORY;
 230         }
 231
 232         /* Copy in what we already read. */
 233         memcpy(*buffer,
 234                 writeX_header,
 235                 4 + STANDARD_WRITE_AND_X_HEADER_SIZE);
 236         toread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
 237
 238         if(toread > 0) {
 239                 status = read_packet_remainder(
 240                         fd, (*buffer) + 4 + STANDARD_WRITE_AND_X_HEADER_SIZE,
 241                         timeout, toread);
 242
 243                 if (!NT_STATUS_IS_OK(status)) {
 244                         DEBUG(10, ("receive_smb_raw_talloc_partial_read: %s\n",
 245                                    nt_errstr(status)));
 246                         return status;
 247                 }
 248         }
 249
 250         *len_ret = len + 4;
 251         return NT_STATUS_OK;
 252 }
 253
 254 static NTSTATUS receive_smb_raw_talloc(TALLOC_CTX *mem_ctx, int fd,
 255                                        char **buffer, unsigned int timeout,
 256                                        size_t *p_unread, size_t *plen)
 257 {
 258         char lenbuf[4];
 259         size_t len;
 260         int min_recv_size = lp_min_receive_file_size();
 261         NTSTATUS status;
 262
 263         *p_unread = 0;
 264
 265         status = read_smb_length_return_keepalive(fd, lenbuf, timeout, &len);
 266         if (!NT_STATUS_IS_OK(status)) {
 267                 DEBUG(10, ("receive_smb_raw: %s\n", nt_errstr(status)));
 268                 return status;
 269         }
 270
 271         if (CVAL(lenbuf,0) == 0 &&
 272                         min_recv_size &&
 273                         smb_len_large(lenbuf) > (min_recv_size + STANDARD_WRITE_AND_X_HEADER_SIZE) && /* Could be a UNIX large writeX. */
 274                         !srv_is_signing_active()) {
 275
 276                 return receive_smb_raw_talloc_partial_read(
 277                         mem_ctx, lenbuf, fd, buffer, timeout, p_unread, plen);
 278         }
 279
 280         if (!valid_packet_size(len)) {
 281                 return NT_STATUS_INVALID_PARAMETER;
 282         }
 283
 284         /*
 285          * The +4 here can't wrap, we've checked the length above already.
 286          */
 287
 288         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
 289
 290         if (*buffer == NULL) {
 291                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
 292                           (int)len+4));
 293                 return NT_STATUS_NO_MEMORY;
 294         }
 295
 296         memcpy(*buffer, lenbuf, sizeof(lenbuf));
 297
 298         status = read_packet_remainder(fd, (*buffer)+4, timeout, len);
 299         if (!NT_STATUS_IS_OK(status)) {
 300                 return status;
 301         }
 302
 303         *plen = len + 4;
 304         return NT_STATUS_OK;
 305 }
 306
 307 static NTSTATUS receive_smb_talloc(TALLOC_CTX *mem_ctx, int fd,
 308                                    char **buffer, unsigned int timeout,
 309                                    size_t *p_unread, bool *p_encrypted,
 310                                    size_t *p_len)
 311 {
 312         size_t len = 0;
 313         NTSTATUS status;
 314
 315         *p_encrypted = false;
 316
 317         status = receive_smb_raw_talloc(mem_ctx, fd, buffer, timeout,
 318                                         p_unread, &len);
 319         if (!NT_STATUS_IS_OK(status)) {
 320                 return status;
 321         }
 322
 323         if (is_encrypted_packet((uint8_t *)*buffer)) {
 324                 status = srv_decrypt_buffer(*buffer);
 325                 if (!NT_STATUS_IS_OK(status)) {
 326                         DEBUG(0, ("receive_smb_talloc: SMB decryption failed on "
 327                                 "incoming packet! Error %s\n",
 328                                 nt_errstr(status) ));
 329                         return status;
 330                 }
 331                 *p_encrypted = true;
 332         }
 333
 334         /* Check the incoming SMB signature. */
 335         if (!srv_check_sign_mac(*buffer, true)) {
 336                 DEBUG(0, ("receive_smb: SMB Signature verification failed on "
 337                           "incoming packet!\n"));
 338                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
 339         }
 340
 341         *p_len = len;
 342         return NT_STATUS_OK;
 343 }
 344
 345 /*
 346  * Initialize a struct smb_request from an inbuf
 347  */
 348
 349 void init_smb_request(struct smb_request *req,
 350                         const uint8 *inbuf,
 351                         size_t unread_bytes,
 352                         bool encrypted)
 353 {
 354         size_t req_size = smb_len(inbuf) + 4;
 355         /* Ensure we have at least smb_size bytes. */
 356         if (req_size < smb_size) {
 357                 DEBUG(0,("init_smb_request: invalid request size %u\n",
 358                         (unsigned int)req_size ));
 359                 exit_server_cleanly("Invalid SMB request");
 360         }
 361         req->cmd    = CVAL(inbuf, smb_com);
 362         req->flags2 = SVAL(inbuf, smb_flg2);
 363         req->smbpid = SVAL(inbuf, smb_pid);
 364         req->mid    = SVAL(inbuf, smb_mid);
 365         req->vuid   = SVAL(inbuf, smb_uid);
 366         req->tid    = SVAL(inbuf, smb_tid);
 367         req->wct    = CVAL(inbuf, smb_wct);
 368         req->vwv    = (uint16_t *)(inbuf+smb_vwv);
 369         req->buflen = smb_buflen(inbuf);
 370         req->buf    = (const uint8_t *)smb_buf(inbuf);
 371         req->unread_bytes = unread_bytes;
 372         req->encrypted = encrypted;
 373         req->conn = conn_find(req->tid);
 374         req->chain_fsp = NULL;
 375         req->chain_outbuf = NULL;
 376
 377         /* Ensure we have at least wct words and 2 bytes of bcc. */
 378         if (smb_size + req->wct*2 > req_size) {
 379                 DEBUG(0,("init_smb_request: invalid wct number %u (size %u)\n",
 380                         (unsigned int)req->wct,
 381                         (unsigned int)req_size));
 382                 exit_server_cleanly("Invalid SMB request");
 383         }
 384         /* Ensure bcc is correct. */
 385         if (((uint8 *)smb_buf(inbuf)) + req->buflen > inbuf + req_size) {
 386                 DEBUG(0,("init_smb_request: invalid bcc number %u "
 387                         "(wct = %u, size %u)\n",
 388                         (unsigned int)req->buflen,
 389                         (unsigned int)req->wct,
 390                         (unsigned int)req_size));
 391                 exit_server_cleanly("Invalid SMB request");
 392         }
 393         req->outbuf = NULL;
 394 }
 395
 396 static void process_smb(struct smbd_server_connection *conn,
 397                         uint8_t *inbuf, size_t nread, size_t unread_bytes,
 398                         bool encrypted);
 399
 400 static void smbd_deferred_open_timer(struct event_context *ev,
 401                                      struct timed_event *te,
 402                                      struct timeval _tval,
 403                                      void *private_data)
 404 {
 405         struct pending_message_list *msg = talloc_get_type(private_data,
 406                                            struct pending_message_list);
 407         TALLOC_CTX *mem_ctx = talloc_tos();
 408         uint8_t *inbuf;
 409
 410         inbuf = (uint8_t *)talloc_memdup(mem_ctx, msg->buf.data,
 411                                          msg->buf.length);
 412         if (inbuf == NULL) {
 413                 exit_server("smbd_deferred_open_timer: talloc failed\n");
 414                 return;
 415         }
 416
 417         /* We leave this message on the queue so the open code can
 418            know this is a retry. */
 419         DEBUG(5,("smbd_deferred_open_timer: trigger mid %u.\n",
 420                 (unsigned int)SVAL(msg->buf.data,smb_mid)));
 421
 422         process_smb(smbd_server_conn, inbuf,
 423                     msg->buf.length, 0,
 424                     msg->encrypted);
 425 }
 426
 427 /****************************************************************************
 428  Function to push a message onto the tail of a linked list of smb messages ready
 429  for processing.
 430 ****************************************************************************/
 431
 432 static bool push_queued_message(struct smb_request *req,
 433                                 struct timeval request_time,
 434                                 struct timeval end_time,
 435                                 char *private_data, size_t private_len)
 436 {
 437         int msg_len = smb_len(req->inbuf) + 4;
 438         struct pending_message_list *msg;
 439
 440         msg = TALLOC_ZERO_P(NULL, struct pending_message_list);
 441
 442         if(msg == NULL) {
 443                 DEBUG(0,("push_message: malloc fail (1)\n"));
 444                 return False;
 445         }
 446
 447         msg->buf = data_blob_talloc(msg, req->inbuf, msg_len);
 448         if(msg->buf.data == NULL) {
 449                 DEBUG(0,("push_message: malloc fail (2)\n"));
 450                 TALLOC_FREE(msg);
 451                 return False;
 452         }
 453
 454         msg->request_time = request_time;
 455         msg->encrypted = req->encrypted;
 456
 457         if (private_data) {
 458                 msg->private_data = data_blob_talloc(msg, private_data,
 459                                                      private_len);
 460                 if (msg->private_data.data == NULL) {
 461                         DEBUG(0,("push_message: malloc fail (3)\n"));
 462                         TALLOC_FREE(msg);
 463                         return False;
 464                 }
 465         }
 466
 467         msg->te = event_add_timed(smbd_event_context(),
 468                                   msg,
 469                                   end_time,
 470                                   smbd_deferred_open_timer,
 471                                   msg);
 472         if (!msg->te) {
 473                 DEBUG(0,("push_message: event_add_timed failed\n"));
 474                 TALLOC_FREE(msg);
 475                 return false;
 476         }
 477
 478         DLIST_ADD_END(deferred_open_queue, msg, struct pending_message_list *);
 479
 480         DEBUG(10,("push_message: pushed message length %u on "
 481                   "deferred_open_queue\n", (unsigned int)msg_len));
 482
 483         return True;
 484 }
 485
 486 /****************************************************************************
 487  Function to delete a sharing violation open message by mid.
 488 ****************************************************************************/
 489
 490 void remove_deferred_open_smb_message(uint16 mid)
 491 {
 492         struct pending_message_list *pml;
 493
 494         for (pml = deferred_open_queue; pml; pml = pml->next) {
 495                 if (mid == SVAL(pml->buf.data,smb_mid)) {
 496                         DEBUG(10,("remove_sharing_violation_open_smb_message: "
 497                                   "deleting mid %u len %u\n",
 498                                   (unsigned int)mid,
 499                                   (unsigned int)pml->buf.length ));
 500                         DLIST_REMOVE(deferred_open_queue, pml);
 501                         TALLOC_FREE(pml);
 502                         return;
 503                 }
 504         }
 505 }
 506
 507 /****************************************************************************
 508  Move a sharing violation open retry message to the front of the list and
 509  schedule it for immediate processing.
 510 ****************************************************************************/
 511
 512 void schedule_deferred_open_smb_message(uint16 mid)
 513 {
 514         struct pending_message_list *pml;
 515         int i = 0;
 516
 517         for (pml = deferred_open_queue; pml; pml = pml->next) {
 518                 uint16 msg_mid = SVAL(pml->buf.data,smb_mid);
 519
 520                 DEBUG(10,("schedule_deferred_open_smb_message: [%d] msg_mid = %u\n", i++,
 521                         (unsigned int)msg_mid ));
 522
 523                 if (mid == msg_mid) {
 524                         struct timed_event *te;
 525
 526                         DEBUG(10,("schedule_deferred_open_smb_message: scheduling mid %u\n",
 527                                 mid ));
 528
 529                         te = event_add_timed(smbd_event_context(),
 530                                              pml,
 531                                              timeval_zero(),
 532                                              smbd_deferred_open_timer,
 533                                              pml);
 534                         if (!te) {
 535                                 DEBUG(10,("schedule_deferred_open_smb_message: "
 536                                           "event_add_timed() failed, skipping mid %u\n",
 537                                           mid ));
 538                         }
 539
 540                         TALLOC_FREE(pml->te);
 541                         pml->te = te;
 542                         DLIST_PROMOTE(deferred_open_queue, pml);
 543                         return;
 544                 }
 545         }
 546
 547         DEBUG(10,("schedule_deferred_open_smb_message: failed to find message mid %u\n",
 548                 mid ));
 549 }
 550
 551 /****************************************************************************
 552  Return true if this mid is on the deferred queue.
 553 ****************************************************************************/
 554
 555 bool open_was_deferred(uint16 mid)
 556 {
 557         struct pending_message_list *pml;
 558
 559         for (pml = deferred_open_queue; pml; pml = pml->next) {
 560                 if (SVAL(pml->buf.data,smb_mid) == mid) {
 561                         return True;
 562                 }
 563         }
 564         return False;
 565 }
 566
 567 /****************************************************************************
 568  Return the message queued by this mid.
 569 ****************************************************************************/
 570
 571 struct pending_message_list *get_open_deferred_message(uint16 mid)
 572 {
 573         struct pending_message_list *pml;
 574
 575         for (pml = deferred_open_queue; pml; pml = pml->next) {
 576                 if (SVAL(pml->buf.data,smb_mid) == mid) {
 577                         return pml;
 578                 }
 579         }
 580         return NULL;
 581 }
 582
 583 /****************************************************************************
 584  Function to push a deferred open smb message onto a linked list of local smb
 585  messages ready for processing.
 586 ****************************************************************************/
 587
 588 bool push_deferred_smb_message(struct smb_request *req,
 589                                struct timeval request_time,
 590                                struct timeval timeout,
 591                                char *private_data, size_t priv_len)
 592 {
 593         struct timeval end_time;
 594
 595         if (req->unread_bytes) {
 596                 DEBUG(0,("push_deferred_smb_message: logic error ! "
 597                         "unread_bytes = %u\n",
 598                         (unsigned int)req->unread_bytes ));
 599                 smb_panic("push_deferred_smb_message: "
 600                         "logic error unread_bytes != 0" );
 601         }
 602
 603         end_time = timeval_sum(&request_time, &timeout);
 604
 605         DEBUG(10,("push_deferred_open_smb_message: pushing message len %u mid %u "
 606                   "timeout time [%u.%06u]\n",
 607                   (unsigned int) smb_len(req->inbuf)+4, (unsigned int)req->mid,
 608                   (unsigned int)end_time.tv_sec,
 609                   (unsigned int)end_time.tv_usec));
 610
 611         return push_queued_message(req, request_time, end_time,
 612                                    private_data, priv_len);
 613 }
 614
 615 struct idle_event {
 616         struct timed_event *te;
 617         struct timeval interval;
 618         char *name;
 619         bool (*handler)(const struct timeval *now, void *private_data);
 620         void *private_data;
 621 };
 622
 623 static void smbd_idle_event_handler(struct event_context *ctx,
 624                                     struct timed_event *te,
 625                                     struct timeval now,
 626                                     void *private_data)
 627 {
 628         struct idle_event *event =
 629                 talloc_get_type_abort(private_data, struct idle_event);
 630
 631         TALLOC_FREE(event->te);
 632
 633         DEBUG(10,("smbd_idle_event_handler: %s %p called\n",
 634                   event->name, event->te));
 635
 636         if (!event->handler(&now, event->private_data)) {
 637                 DEBUG(10,("smbd_idle_event_handler: %s %p stopped\n",
 638                           event->name, event->te));
 639                 /* Don't repeat, delete ourselves */
 640                 TALLOC_FREE(event);
 641                 return;
 642         }
 643
 644         DEBUG(10,("smbd_idle_event_handler: %s %p rescheduled\n",
 645                   event->name, event->te));
 646
 647         event->te = event_add_timed(ctx, event,
 648                                     timeval_sum(&now, &event->interval),
 649                                     smbd_idle_event_handler, event);
 650
 651         /* We can't do much but fail here. */
 652         SMB_ASSERT(event->te != NULL);
 653 }
 654
 655 struct idle_event *event_add_idle(struct event_context *event_ctx,
 656                                   TALLOC_CTX *mem_ctx,
 657                                   struct timeval interval,
 658                                   const char *name,
 659                                   bool (*handler)(const struct timeval *now,
 660                                                   void *private_data),
 661                                   void *private_data)
 662 {
 663         struct idle_event *result;
 664         struct timeval now = timeval_current();
 665
 666         result = TALLOC_P(mem_ctx, struct idle_event);
 667         if (result == NULL) {
 668                 DEBUG(0, ("talloc failed\n"));
 669                 return NULL;
 670         }
 671
 672         result->interval = interval;
 673         result->handler = handler;
 674         result->private_data = private_data;
 675
 676         if (!(result->name = talloc_asprintf(result, "idle_evt(%s)", name))) {
 677                 DEBUG(0, ("talloc failed\n"));
 678                 TALLOC_FREE(result);
 679                 return NULL;
 680         }
 681
 682         result->te = event_add_timed(event_ctx, result,
 683                                      timeval_sum(&now, &interval),
 684                                      smbd_idle_event_handler, result);
 685         if (result->te == NULL) {
 686                 DEBUG(0, ("event_add_timed failed\n"));
 687                 TALLOC_FREE(result);
 688                 return NULL;
 689         }
 690
 691         DEBUG(10,("event_add_idle: %s %p\n", result->name, result->te));
 692         return result;
 693 }
 694
 695 static void smbd_sig_term_handler(struct tevent_context *ev,
 696                                   struct tevent_signal *se,
 697                                   int signum,
 698                                   int count,
 699                                   void *siginfo,
 700                                   void *private_data)
 701 {
 702         exit_server_cleanly("termination signal");
 703 }
 704
 705 void smbd_setup_sig_term_handler(void)
 706 {
 707         struct tevent_signal *se;
 708
 709         se = tevent_add_signal(smbd_event_context(),
 710                                smbd_event_context(),
 711                                SIGTERM, 0,
 712                                smbd_sig_term_handler,
 713                                NULL);
 714         if (!se) {
 715                 exit_server("failed to setup SIGTERM handler");
 716         }
 717 }
 718
 719 static void smbd_sig_hup_handler(struct tevent_context *ev,
 720                                   struct tevent_signal *se,
 721                                   int signum,
 722                                   int count,
 723                                   void *siginfo,
 724                                   void *private_data)
 725 {
 726         change_to_root_user();
 727         DEBUG(1,("Reloading services after SIGHUP\n"));
 728         reload_services(False);
 729 }
 730
 731 void smbd_setup_sig_hup_handler(void)
 732 {
 733         struct tevent_signal *se;
 734
 735         se = tevent_add_signal(smbd_event_context(),
 736                                smbd_event_context(),
 737                                SIGHUP, 0,
 738                                smbd_sig_hup_handler,
 739                                NULL);
 740         if (!se) {
 741                 exit_server("failed to setup SIGHUP handler");
 742         }
 743 }
 744
 745 /****************************************************************************
 746  Do all async processing in here. This includes kernel oplock messages, change
 747  notify events etc.
 748 ****************************************************************************/
 749
 750 static void async_processing(void)
 751 {
 752         DEBUG(10,("async_processing: Doing async processing.\n"));
 753
 754         process_aio_queue();
 755
 756         process_kernel_oplocks(smbd_messaging_context());
 757
 758         /* Do the aio check again after receive_local_message as it does a
 759            select and may have eaten our signal. */
 760         /* Is this till true? -- vl */
 761         process_aio_queue();
 762 }
 763
 764 /****************************************************************************
 765   Do a select on an two fd's - with timeout.
 766
 767   If a local udp message has been pushed onto the
 768   queue (this can only happen during oplock break
 769   processing) call async_processing()
 770
 771   If a pending smb message has been pushed onto the
 772   queue (this can only happen during oplock break
 773   processing) return this next.
 774
 775   If the first smbfd is ready then read an smb from it.
 776   if the second (loopback UDP) fd is ready then read a message
 777   from it and setup the buffer header to identify the length
 778   and from address.
 779   Returns False on timeout or error.
 780   Else returns True.
 781
 782 The timeout is in milliseconds
 783 ****************************************************************************/
 784
 785 static NTSTATUS smbd_server_connection_loop_once(struct smbd_server_connection *conn)
 786 {
 787         fd_set r_fds, w_fds;
 788         int selrtn;
 789         struct timeval to;
 790         int maxfd = 0;
 791
 792         to.tv_sec = SMBD_SELECT_TIMEOUT;
 793         to.tv_usec = 0;
 794
 795         /*
 796          * Setup the select fd sets.
 797          */
 798
 799         FD_ZERO(&r_fds);
 800         FD_ZERO(&w_fds);
 801
 802         /*
 803          * Ensure we process oplock break messages by preference.
 804          * We have to do this before the select, after the select
 805          * and if the select returns EINTR. This is due to the fact
 806          * that the selects called from async_processing can eat an EINTR
 807          * caused by a signal (we can't take the break message there).
 808          * This is hideously complex - *MUST* be simplified for 3.0 ! JRA.
 809          */
 810
 811         if (oplock_message_waiting()) {
 812                 DEBUG(10,("receive_message_or_smb: oplock_message is waiting.\n"));
 813                 async_processing();
 814                 /*
 815                  * After async processing we must go and do the select again, as
 816                  * the state of the flag in fds for the server file descriptor is
 817                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 818                  */
 819                 return NT_STATUS_RETRY;
 820         }
 821
 822         /*
 823          * Are there any timed events waiting ? If so, ensure we don't
 824          * select for longer than it would take to wait for them.
 825          */
 826
 827         {
 828                 struct timeval now;
 829                 GetTimeOfDay(&now);
 830
 831                 event_add_to_select_args(smbd_event_context(), &now,
 832                                          &r_fds, &w_fds, &to, &maxfd);
 833         }
 834
 835         /* Process a signal and timed events now... */
 836         if (run_events(smbd_event_context(), 0, NULL, NULL)) {
 837                 return NT_STATUS_RETRY;
 838         }
 839
 840         {
 841                 int sav;
 842                 START_PROFILE(smbd_idle);
 843
 844                 selrtn = sys_select(maxfd+1,&r_fds,&w_fds,NULL,&to);
 845                 sav = errno;
 846
 847                 END_PROFILE(smbd_idle);
 848                 errno = sav;
 849         }
 850
 851         if (run_events(smbd_event_context(), selrtn, &r_fds, &w_fds)) {
 852                 return NT_STATUS_RETRY;
 853         }
 854
 855         /* if we get EINTR then maybe we have received an oplock
 856            signal - treat this as select returning 1. This is ugly, but
 857            is the best we can do until the oplock code knows more about
 858            signals */
 859         if (selrtn == -1 && errno == EINTR) {
 860                 async_processing();
 861                 /*
 862                  * After async processing we must go and do the select again, as
 863                  * the state of the flag in fds for the server file descriptor is
 864                  * indeterminate - we may have done I/O on it in the oplock processing. JRA.
 865                  */
 866                 return NT_STATUS_RETRY;
 867         }
 868
 869         /* Check if error */
 870         if (selrtn == -1) {
 871                 /* something is wrong. Maybe the socket is dead? */
 872                 return map_nt_error_from_unix(errno);
 873         }
 874
 875         /* Did we timeout ? */
 876         if (selrtn == 0) {
 877                 return NT_STATUS_RETRY;
 878         }
 879
 880         /* should not be reached */
 881         return NT_STATUS_INTERNAL_ERROR;
 882 }
 883
 884 /*
 885  * Only allow 5 outstanding trans requests. We're allocating memory, so
 886  * prevent a DoS.
 887  */
 888
 889 NTSTATUS allow_new_trans(struct trans_state *list, int mid)
 890 {
 891         int count = 0;
 892         for (; list != NULL; list = list->next) {
 893
 894                 if (list->mid == mid) {
 895                         return NT_STATUS_INVALID_PARAMETER;
 896                 }
 897
 898                 count += 1;
 899         }
 900         if (count > 5) {
 901                 return NT_STATUS_INSUFFICIENT_RESOURCES;
 902         }
 903
 904         return NT_STATUS_OK;
 905 }
 906
 907 /****************************************************************************
 908  We're terminating and have closed all our files/connections etc.
 909  If there are any pending local messages we need to respond to them
 910  before termination so that other smbds don't think we just died whilst
 911  holding oplocks.
 912 ****************************************************************************/
 913
 914 void respond_to_all_remaining_local_messages(void)
 915 {
 916         /*
 917          * Assert we have no exclusive open oplocks.
 918          */
 919
 920         if(get_number_of_exclusive_open_oplocks()) {
 921                 DEBUG(0,("respond_to_all_remaining_local_messages: PANIC : we have %d exclusive oplocks.\n",
 922                         get_number_of_exclusive_open_oplocks() ));
 923                 return;
 924         }
 925
 926         process_kernel_oplocks(smbd_messaging_context());
 927
 928         return;
 929 }
 930
 931
 932 /*
 933 These flags determine some of the permissions required to do an operation
 934
 935 Note that I don't set NEED_WRITE on some write operations because they
 936 are used by some brain-dead clients when printing, and I don't want to
 937 force write permissions on print services.
 938 */
 939 #define AS_USER (1<<0)
 940 #define NEED_WRITE (1<<1) /* Must be paired with AS_USER */
 941 #define TIME_INIT (1<<2)
 942 #define CAN_IPC (1<<3) /* Must be paired with AS_USER */
 943 #define AS_GUEST (1<<5) /* Must *NOT* be paired with AS_USER */
 944 #define DO_CHDIR (1<<6)
 945
 946 /*
 947    define a list of possible SMB messages and their corresponding
 948    functions. Any message that has a NULL function is unimplemented -
 949    please feel free to contribute implementations!
 950 */
 951 static const struct smb_message_struct {
 952         const char *name;
 953         void (*fn)(struct smb_request *req);
 954         int flags;
 955 } smb_messages[256] = {
 956
 957 /* 0x00 */ { "SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE},
 958 /* 0x01 */ { "SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE},
 959 /* 0x02 */ { "SMBopen",reply_open,AS_USER },
 960 /* 0x03 */ { "SMBcreate",reply_mknew,AS_USER},
 961 /* 0x04 */ { "SMBclose",reply_close,AS_USER | CAN_IPC },
 962 /* 0x05 */ { "SMBflush",reply_flush,AS_USER},
 963 /* 0x06 */ { "SMBunlink",reply_unlink,AS_USER | NEED_WRITE },
 964 /* 0x07 */ { "SMBmv",reply_mv,AS_USER | NEED_WRITE },
 965 /* 0x08 */ { "SMBgetatr",reply_getatr,AS_USER},
 966 /* 0x09 */ { "SMBsetatr",reply_setatr,AS_USER | NEED_WRITE},
 967 /* 0x0a */ { "SMBread",reply_read,AS_USER},
 968 /* 0x0b */ { "SMBwrite",reply_write,AS_USER | CAN_IPC },
 969 /* 0x0c */ { "SMBlock",reply_lock,AS_USER},
 970 /* 0x0d */ { "SMBunlock",reply_unlock,AS_USER},
 971 /* 0x0e */ { "SMBctemp",reply_ctemp,AS_USER },
 972 /* 0x0f */ { "SMBmknew",reply_mknew,AS_USER},
 973 /* 0x10 */ { "SMBcheckpath",reply_checkpath,AS_USER},
 974 /* 0x11 */ { "SMBexit",reply_exit,DO_CHDIR},
 975 /* 0x12 */ { "SMBlseek",reply_lseek,AS_USER},
 976 /* 0x13 */ { "SMBlockread",reply_lockread,AS_USER},
 977 /* 0x14 */ { "SMBwriteunlock",reply_writeunlock,AS_USER},
 978 /* 0x15 */ { NULL, NULL, 0 },
 979 /* 0x16 */ { NULL, NULL, 0 },
 980 /* 0x17 */ { NULL, NULL, 0 },
 981 /* 0x18 */ { NULL, NULL, 0 },
 982 /* 0x19 */ { NULL, NULL, 0 },
 983 /* 0x1a */ { "SMBreadbraw",reply_readbraw,AS_USER},
 984 /* 0x1b */ { "SMBreadBmpx",reply_readbmpx,AS_USER},
 985 /* 0x1c */ { "SMBreadBs",reply_readbs,AS_USER },
 986 /* 0x1d */ { "SMBwritebraw",reply_writebraw,AS_USER},
 987 /* 0x1e */ { "SMBwriteBmpx",reply_writebmpx,AS_USER},
 988 /* 0x1f */ { "SMBwriteBs",reply_writebs,AS_USER},
 989 /* 0x20 */ { "SMBwritec", NULL,0},
 990 /* 0x21 */ { NULL, NULL, 0 },
 991 /* 0x22 */ { "SMBsetattrE",reply_setattrE,AS_USER | NEED_WRITE },
 992 /* 0x23 */ { "SMBgetattrE",reply_getattrE,AS_USER },
 993 /* 0x24 */ { "SMBlockingX",reply_lockingX,AS_USER },
 994 /* 0x25 */ { "SMBtrans",reply_trans,AS_USER | CAN_IPC },
 995 /* 0x26 */ { "SMBtranss",reply_transs,AS_USER | CAN_IPC},
 996 /* 0x27 */ { "SMBioctl",reply_ioctl,0},
 997 /* 0x28 */ { "SMBioctls", NULL,AS_USER},
 998 /* 0x29 */ { "SMBcopy",reply_copy,AS_USER | NEED_WRITE },
 999 /* 0x2a */ { "SMBmove", NULL,AS_USER | NEED_WRITE },
1000 /* 0x2b */ { "SMBecho",reply_echo,0},
1001 /* 0x2c */ { "SMBwriteclose",reply_writeclose,AS_USER},
1002 /* 0x2d */ { "SMBopenX",reply_open_and_X,AS_USER | CAN_IPC },
1003 /* 0x2e */ { "SMBreadX",reply_read_and_X,AS_USER | CAN_IPC },
1004 /* 0x2f */ { "SMBwriteX",reply_write_and_X,AS_USER | CAN_IPC },
1005 /* 0x30 */ { NULL, NULL, 0 },
1006 /* 0x31 */ { NULL, NULL, 0 },
1007 /* 0x32 */ { "SMBtrans2",reply_trans2, AS_USER | CAN_IPC },
1008 /* 0x33 */ { "SMBtranss2",reply_transs2, AS_USER},
1009 /* 0x34 */ { "SMBfindclose",reply_findclose,AS_USER},
1010 /* 0x35 */ { "SMBfindnclose",reply_findnclose,AS_USER},
1011 /* 0x36 */ { NULL, NULL, 0 },
1012 /* 0x37 */ { NULL, NULL, 0 },
1013 /* 0x38 */ { NULL, NULL, 0 },
1014 /* 0x39 */ { NULL, NULL, 0 },
1015 /* 0x3a */ { NULL, NULL, 0 },
1016 /* 0x3b */ { NULL, NULL, 0 },
1017 /* 0x3c */ { NULL, NULL, 0 },
1018 /* 0x3d */ { NULL, NULL, 0 },
1019 /* 0x3e */ { NULL, NULL, 0 },
1020 /* 0x3f */ { NULL, NULL, 0 },
1021 /* 0x40 */ { NULL, NULL, 0 },
1022 /* 0x41 */ { NULL, NULL, 0 },
1023 /* 0x42 */ { NULL, NULL, 0 },
1024 /* 0x43 */ { NULL, NULL, 0 },
1025 /* 0x44 */ { NULL, NULL, 0 },
1026 /* 0x45 */ { NULL, NULL, 0 },
1027 /* 0x46 */ { NULL, NULL, 0 },
1028 /* 0x47 */ { NULL, NULL, 0 },
1029 /* 0x48 */ { NULL, NULL, 0 },
1030 /* 0x49 */ { NULL, NULL, 0 },
1031 /* 0x4a */ { NULL, NULL, 0 },
1032 /* 0x4b */ { NULL, NULL, 0 },
1033 /* 0x4c */ { NULL, NULL, 0 },
1034 /* 0x4d */ { NULL, NULL, 0 },
1035 /* 0x4e */ { NULL, NULL, 0 },
1036 /* 0x4f */ { NULL, NULL, 0 },
1037 /* 0x50 */ { NULL, NULL, 0 },
1038 /* 0x51 */ { NULL, NULL, 0 },
1039 /* 0x52 */ { NULL, NULL, 0 },
1040 /* 0x53 */ { NULL, NULL, 0 },
1041 /* 0x54 */ { NULL, NULL, 0 },
1042 /* 0x55 */ { NULL, NULL, 0 },
1043 /* 0x56 */ { NULL, NULL, 0 },
1044 /* 0x57 */ { NULL, NULL, 0 },
1045 /* 0x58 */ { NULL, NULL, 0 },
1046 /* 0x59 */ { NULL, NULL, 0 },
1047 /* 0x5a */ { NULL, NULL, 0 },
1048 /* 0x5b */ { NULL, NULL, 0 },
1049 /* 0x5c */ { NULL, NULL, 0 },
1050 /* 0x5d */ { NULL, NULL, 0 },
1051 /* 0x5e */ { NULL, NULL, 0 },
1052 /* 0x5f */ { NULL, NULL, 0 },
1053 /* 0x60 */ { NULL, NULL, 0 },
1054 /* 0x61 */ { NULL, NULL, 0 },
1055 /* 0x62 */ { NULL, NULL, 0 },
1056 /* 0x63 */ { NULL, NULL, 0 },
1057 /* 0x64 */ { NULL, NULL, 0 },
1058 /* 0x65 */ { NULL, NULL, 0 },
1059 /* 0x66 */ { NULL, NULL, 0 },
1060 /* 0x67 */ { NULL, NULL, 0 },
1061 /* 0x68 */ { NULL, NULL, 0 },
1062 /* 0x69 */ { NULL, NULL, 0 },
1063 /* 0x6a */ { NULL, NULL, 0 },
1064 /* 0x6b */ { NULL, NULL, 0 },
1065 /* 0x6c */ { NULL, NULL, 0 },
1066 /* 0x6d */ { NULL, NULL, 0 },
1067 /* 0x6e */ { NULL, NULL, 0 },
1068 /* 0x6f */ { NULL, NULL, 0 },
1069 /* 0x70 */ { "SMBtcon",reply_tcon,0},
1070 /* 0x71 */ { "SMBtdis",reply_tdis,DO_CHDIR},
1071 /* 0x72 */ { "SMBnegprot",reply_negprot,0},
1072 /* 0x73 */ { "SMBsesssetupX",reply_sesssetup_and_X,0},
1073 /* 0x74 */ { "SMBulogoffX",reply_ulogoffX, 0}, /* ulogoff doesn't give a valid TID */
1074 /* 0x75 */ { "SMBtconX",reply_tcon_and_X,0},
1075 /* 0x76 */ { NULL, NULL, 0 },
1076 /* 0x77 */ { NULL, NULL, 0 },
1077 /* 0x78 */ { NULL, NULL, 0 },
1078 /* 0x79 */ { NULL, NULL, 0 },
1079 /* 0x7a */ { NULL, NULL, 0 },
1080 /* 0x7b */ { NULL, NULL, 0 },
1081 /* 0x7c */ { NULL, NULL, 0 },
1082 /* 0x7d */ { NULL, NULL, 0 },
1083 /* 0x7e */ { NULL, NULL, 0 },
1084 /* 0x7f */ { NULL, NULL, 0 },
1085 /* 0x80 */ { "SMBdskattr",reply_dskattr,AS_USER},
1086 /* 0x81 */ { "SMBsearch",reply_search,AS_USER},
1087 /* 0x82 */ { "SMBffirst",reply_search,AS_USER},
1088 /* 0x83 */ { "SMBfunique",reply_search,AS_USER},
1089 /* 0x84 */ { "SMBfclose",reply_fclose,AS_USER},
1090 /* 0x85 */ { NULL, NULL, 0 },
1091 /* 0x86 */ { NULL, NULL, 0 },
1092 /* 0x87 */ { NULL, NULL, 0 },
1093 /* 0x88 */ { NULL, NULL, 0 },
1094 /* 0x89 */ { NULL, NULL, 0 },
1095 /* 0x8a */ { NULL, NULL, 0 },
1096 /* 0x8b */ { NULL, NULL, 0 },
1097 /* 0x8c */ { NULL, NULL, 0 },
1098 /* 0x8d */ { NULL, NULL, 0 },
1099 /* 0x8e */ { NULL, NULL, 0 },
1100 /* 0x8f */ { NULL, NULL, 0 },
1101 /* 0x90 */ { NULL, NULL, 0 },
1102 /* 0x91 */ { NULL, NULL, 0 },
1103 /* 0x92 */ { NULL, NULL, 0 },
1104 /* 0x93 */ { NULL, NULL, 0 },
1105 /* 0x94 */ { NULL, NULL, 0 },
1106 /* 0x95 */ { NULL, NULL, 0 },
1107 /* 0x96 */ { NULL, NULL, 0 },
1108 /* 0x97 */ { NULL, NULL, 0 },
1109 /* 0x98 */ { NULL, NULL, 0 },
1110 /* 0x99 */ { NULL, NULL, 0 },
1111 /* 0x9a */ { NULL, NULL, 0 },
1112 /* 0x9b */ { NULL, NULL, 0 },
1113 /* 0x9c */ { NULL, NULL, 0 },
1114 /* 0x9d */ { NULL, NULL, 0 },
1115 /* 0x9e */ { NULL, NULL, 0 },
1116 /* 0x9f */ { NULL, NULL, 0 },
1117 /* 0xa0 */ { "SMBnttrans",reply_nttrans, AS_USER | CAN_IPC },
1118 /* 0xa1 */ { "SMBnttranss",reply_nttranss, AS_USER | CAN_IPC },
1119 /* 0xa2 */ { "SMBntcreateX",reply_ntcreate_and_X, AS_USER | CAN_IPC },
1120 /* 0xa3 */ { NULL, NULL, 0 },
1121 /* 0xa4 */ { "SMBntcancel",reply_ntcancel, 0 },
1122 /* 0xa5 */ { "SMBntrename",reply_ntrename, AS_USER | NEED_WRITE },
1123 /* 0xa6 */ { NULL, NULL, 0 },
1124 /* 0xa7 */ { NULL, NULL, 0 },
1125 /* 0xa8 */ { NULL, NULL, 0 },
1126 /* 0xa9 */ { NULL, NULL, 0 },
1127 /* 0xaa */ { NULL, NULL, 0 },
1128 /* 0xab */ { NULL, NULL, 0 },
1129 /* 0xac */ { NULL, NULL, 0 },
1130 /* 0xad */ { NULL, NULL, 0 },
1131 /* 0xae */ { NULL, NULL, 0 },
1132 /* 0xaf */ { NULL, NULL, 0 },
1133 /* 0xb0 */ { NULL, NULL, 0 },
1134 /* 0xb1 */ { NULL, NULL, 0 },
1135 /* 0xb2 */ { NULL, NULL, 0 },
1136 /* 0xb3 */ { NULL, NULL, 0 },
1137 /* 0xb4 */ { NULL, NULL, 0 },
1138 /* 0xb5 */ { NULL, NULL, 0 },
1139 /* 0xb6 */ { NULL, NULL, 0 },
1140 /* 0xb7 */ { NULL, NULL, 0 },
1141 /* 0xb8 */ { NULL, NULL, 0 },
1142 /* 0xb9 */ { NULL, NULL, 0 },
1143 /* 0xba */ { NULL, NULL, 0 },
1144 /* 0xbb */ { NULL, NULL, 0 },
1145 /* 0xbc */ { NULL, NULL, 0 },
1146 /* 0xbd */ { NULL, NULL, 0 },
1147 /* 0xbe */ { NULL, NULL, 0 },
1148 /* 0xbf */ { NULL, NULL, 0 },
1149 /* 0xc0 */ { "SMBsplopen",reply_printopen,AS_USER},
1150 /* 0xc1 */ { "SMBsplwr",reply_printwrite,AS_USER},
1151 /* 0xc2 */ { "SMBsplclose",reply_printclose,AS_USER},
1152 /* 0xc3 */ { "SMBsplretq",reply_printqueue,AS_USER},
1153 /* 0xc4 */ { NULL, NULL, 0 },
1154 /* 0xc5 */ { NULL, NULL, 0 },
1155 /* 0xc6 */ { NULL, NULL, 0 },
1156 /* 0xc7 */ { NULL, NULL, 0 },
1157 /* 0xc8 */ { NULL, NULL, 0 },
1158 /* 0xc9 */ { NULL, NULL, 0 },
1159 /* 0xca */ { NULL, NULL, 0 },
1160 /* 0xcb */ { NULL, NULL, 0 },
1161 /* 0xcc */ { NULL, NULL, 0 },
1162 /* 0xcd */ { NULL, NULL, 0 },
1163 /* 0xce */ { NULL, NULL, 0 },
1164 /* 0xcf */ { NULL, NULL, 0 },
1165 /* 0xd0 */ { "SMBsends",reply_sends,AS_GUEST},
1166 /* 0xd1 */ { "SMBsendb", NULL,AS_GUEST},
1167 /* 0xd2 */ { "SMBfwdname", NULL,AS_GUEST},
1168 /* 0xd3 */ { "SMBcancelf", NULL,AS_GUEST},
1169 /* 0xd4 */ { "SMBgetmac", NULL,AS_GUEST},
1170 /* 0xd5 */ { "SMBsendstrt",reply_sendstrt,AS_GUEST},
1171 /* 0xd6 */ { "SMBsendend",reply_sendend,AS_GUEST},
1172 /* 0xd7 */ { "SMBsendtxt",reply_sendtxt,AS_GUEST},
1173 /* 0xd8 */ { NULL, NULL, 0 },
1174 /* 0xd9 */ { NULL, NULL, 0 },
1175 /* 0xda */ { NULL, NULL, 0 },
1176 /* 0xdb */ { NULL, NULL, 0 },
1177 /* 0xdc */ { NULL, NULL, 0 },
1178 /* 0xdd */ { NULL, NULL, 0 },
1179 /* 0xde */ { NULL, NULL, 0 },
1180 /* 0xdf */ { NULL, NULL, 0 },
1181 /* 0xe0 */ { NULL, NULL, 0 },
1182 /* 0xe1 */ { NULL, NULL, 0 },
1183 /* 0xe2 */ { NULL, NULL, 0 },
1184 /* 0xe3 */ { NULL, NULL, 0 },
1185 /* 0xe4 */ { NULL, NULL, 0 },
1186 /* 0xe5 */ { NULL, NULL, 0 },
1187 /* 0xe6 */ { NULL, NULL, 0 },
1188 /* 0xe7 */ { NULL, NULL, 0 },
1189 /* 0xe8 */ { NULL, NULL, 0 },
1190 /* 0xe9 */ { NULL, NULL, 0 },
1191 /* 0xea */ { NULL, NULL, 0 },
1192 /* 0xeb */ { NULL, NULL, 0 },
1193 /* 0xec */ { NULL, NULL, 0 },
1194 /* 0xed */ { NULL, NULL, 0 },
1195 /* 0xee */ { NULL, NULL, 0 },
1196 /* 0xef */ { NULL, NULL, 0 },
1197 /* 0xf0 */ { NULL, NULL, 0 },
1198 /* 0xf1 */ { NULL, NULL, 0 },
1199 /* 0xf2 */ { NULL, NULL, 0 },
1200 /* 0xf3 */ { NULL, NULL, 0 },
1201 /* 0xf4 */ { NULL, NULL, 0 },
1202 /* 0xf5 */ { NULL, NULL, 0 },
1203 /* 0xf6 */ { NULL, NULL, 0 },
1204 /* 0xf7 */ { NULL, NULL, 0 },
1205 /* 0xf8 */ { NULL, NULL, 0 },
1206 /* 0xf9 */ { NULL, NULL, 0 },
1207 /* 0xfa */ { NULL, NULL, 0 },
1208 /* 0xfb */ { NULL, NULL, 0 },
1209 /* 0xfc */ { NULL, NULL, 0 },
1210 /* 0xfd */ { NULL, NULL, 0 },
1211 /* 0xfe */ { NULL, NULL, 0 },
1212 /* 0xff */ { NULL, NULL, 0 }
1213
1214 };
1215
1216 /*******************************************************************
1217  allocate and initialize a reply packet
1218 ********************************************************************/
1219
1220 static bool create_outbuf(TALLOC_CTX *mem_ctx, struct smb_request *req,
1221                           const char *inbuf, char **outbuf, uint8_t num_words,
1222                           uint32_t num_bytes)
1223 {
1224         /*
1225          * Protect against integer wrap
1226          */
1227         if ((num_bytes > 0xffffff)
1228             || ((num_bytes + smb_size + num_words*2) > 0xffffff)) {
1229                 char *msg;
1230                 if (asprintf(&msg, "num_bytes too large: %u",
1231                              (unsigned)num_bytes) == -1) {
1232                         msg = CONST_DISCARD(char *, "num_bytes too large");
1233                 }
1234                 smb_panic(msg);
1235         }
1236
1237         *outbuf = TALLOC_ARRAY(mem_ctx, char,
1238                                smb_size + num_words*2 + num_bytes);
1239         if (*outbuf == NULL) {
1240                 return false;
1241         }
1242
1243         construct_reply_common(req, inbuf, *outbuf);
1244         srv_set_message(*outbuf, num_words, num_bytes, false);
1245         /*
1246          * Zero out the word area, the caller has to take care of the bcc area
1247          * himself
1248          */
1249         if (num_words != 0) {
1250                 memset(*outbuf + smb_vwv0, 0, num_words*2);
1251         }
1252
1253         return true;
1254 }
1255
1256 void reply_outbuf(struct smb_request *req, uint8 num_words, uint32 num_bytes)
1257 {
1258         char *outbuf;
1259         if (!create_outbuf(req, req, (char *)req->inbuf, &outbuf, num_words,
1260                            num_bytes)) {
1261                 smb_panic("could not allocate output buffer\n");
1262         }
1263         req->outbuf = (uint8_t *)outbuf;
1264 }
1265
1266
1267 /*******************************************************************
1268  Dump a packet to a file.
1269 ********************************************************************/
1270
1271 static void smb_dump(const char *name, int type, const char *data, ssize_t len)
1272 {
1273         int fd, i;
1274         char *fname = NULL;
1275         if (DEBUGLEVEL < 50) {
1276                 return;
1277         }
1278
1279         if (len < 4) len = smb_len(data)+4;
1280         for (i=1;i<100;i++) {
1281                 if (asprintf(&fname, "/tmp/%s.%d.%s", name, i,
1282                              type ? "req" : "resp") == -1) {
1283                         return;
1284                 }
1285                 fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0644);
1286                 if (fd != -1 || errno != EEXIST) break;
1287         }
1288         if (fd != -1) {
1289                 ssize_t ret = write(fd, data, len);
1290                 if (ret != len)
1291                         DEBUG(0,("smb_dump: problem: write returned %d\n", (int)ret ));
1292                 close(fd);
1293                 DEBUG(0,("created %s len %lu\n", fname, (unsigned long)len));
1294         }
1295         SAFE_FREE(fname);
1296 }
1297
1298 /****************************************************************************
1299  Prepare everything for calling the actual request function, and potentially
1300  call the request function via the "new" interface.
1301
1302  Return False if the "legacy" function needs to be called, everything is
1303  prepared.
1304
1305  Return True if we're done.
1306
1307  I know this API sucks, but it is the one with the least code change I could
1308  find.
1309 ****************************************************************************/
1310
1311 static connection_struct *switch_message(uint8 type, struct smb_request *req, int size)
1312 {
1313         int flags;
1314         uint16 session_tag;
1315         connection_struct *conn = NULL;
1316
1317         errno = 0;
1318
1319         /* Make sure this is an SMB packet. smb_size contains NetBIOS header
1320          * so subtract 4 from it. */
1321         if (!valid_smb_header(req->inbuf)
1322             || (size < (smb_size - 4))) {
1323                 DEBUG(2,("Non-SMB packet of length %d. Terminating server\n",
1324                          smb_len(req->inbuf)));
1325                 exit_server_cleanly("Non-SMB packet");
1326         }
1327
1328         if (smb_messages[type].fn == NULL) {
1329                 DEBUG(0,("Unknown message type %d!\n",type));
1330                 smb_dump("Unknown", 1, (char *)req->inbuf, size);
1331                 reply_unknown_new(req, type);
1332                 return NULL;
1333         }
1334
1335         flags = smb_messages[type].flags;
1336
1337         /* In share mode security we must ignore the vuid. */
1338         session_tag = (lp_security() == SEC_SHARE)
1339                 ? UID_FIELD_INVALID : req->vuid;
1340         conn = req->conn;
1341
1342         DEBUG(3,("switch message %s (pid %d) conn 0x%lx\n", smb_fn_name(type),
1343                  (int)sys_getpid(), (unsigned long)conn));
1344
1345         smb_dump(smb_fn_name(type), 1, (char *)req->inbuf, size);
1346
1347         /* Ensure this value is replaced in the incoming packet. */
1348         SSVAL(req->inbuf,smb_uid,session_tag);
1349
1350         /*
1351          * Ensure the correct username is in current_user_info.  This is a
1352          * really ugly bugfix for problems with multiple session_setup_and_X's
1353          * being done and allowing %U and %G substitutions to work correctly.
1354          * There is a reason this code is done here, don't move it unless you
1355          * know what you're doing... :-).
1356          * JRA.
1357          */
1358
1359         if (session_tag != last_session_tag) {
1360                 user_struct *vuser = NULL;
1361
1362                 last_session_tag = session_tag;
1363                 if(session_tag != UID_FIELD_INVALID) {
1364                         vuser = get_valid_user_struct(session_tag);
1365                         if (vuser) {
1366                                 set_current_user_info(
1367                                         vuser->server_info->sanitized_username,
1368                                         vuser->server_info->unix_name,
1369                                         pdb_get_domain(vuser->server_info
1370                                                        ->sam_account));
1371                         }
1372                 }
1373         }
1374
1375         /* Does this call need to be run as the connected user? */
1376         if (flags & AS_USER) {
1377
1378                 /* Does this call need a valid tree connection? */
1379                 if (!conn) {
1380                         /*
1381                          * Amazingly, the error code depends on the command
1382                          * (from Samba4).
1383                          */
1384                         if (type == SMBntcreateX) {
1385                                 reply_nterror(req, NT_STATUS_INVALID_HANDLE);
1386                         } else {
1387                                 reply_doserror(req, ERRSRV, ERRinvnid);
1388                         }
1389                         return NULL;
1390                 }
1391
1392                 if (!change_to_user(conn,session_tag)) {
1393                         reply_nterror(req, NT_STATUS_DOS(ERRSRV, ERRbaduid));
1394                         remove_deferred_open_smb_message(req->mid);
1395                         return conn;
1396                 }
1397
1398                 /* All NEED_WRITE and CAN_IPC flags must also have AS_USER. */
1399
1400                 /* Does it need write permission? */
1401                 if ((flags & NEED_WRITE) && !CAN_WRITE(conn)) {
1402                         reply_nterror(req, NT_STATUS_MEDIA_WRITE_PROTECTED);
1403                         return conn;
1404                 }
1405
1406                 /* IPC services are limited */
1407                 if (IS_IPC(conn) && !(flags & CAN_IPC)) {
1408                         reply_doserror(req, ERRSRV,ERRaccess);
1409                         return conn;
1410                 }
1411         } else {
1412                 /* This call needs to be run as root */
1413                 change_to_root_user();
1414         }
1415
1416         /* load service specific parameters */
1417         if (conn) {
1418                 if (req->encrypted) {
1419                         conn->encrypted_tid = true;
1420                         /* encrypted required from now on. */
1421                         conn->encrypt_level = Required;
1422                 } else if (ENCRYPTION_REQUIRED(conn)) {
1423                         if (req->cmd != SMBtrans2 && req->cmd != SMBtranss2) {
1424                                 exit_server_cleanly("encryption required "
1425                                         "on connection");
1426                                 return conn;
1427                         }
1428                 }
1429
1430                 if (!set_current_service(conn,SVAL(req->inbuf,smb_flg),
1431                                          (flags & (AS_USER|DO_CHDIR)
1432                                           ?True:False))) {
1433                         reply_doserror(req, ERRSRV, ERRaccess);
1434                         return conn;
1435                 }
1436                 conn->num_smb_operations++;
1437         }
1438
1439         /* does this protocol need to be run as guest? */
1440         if ((flags & AS_GUEST)
1441             && (!change_to_guest() ||
1442                 !check_access(smbd_server_fd(), lp_hostsallow(-1),
1443                               lp_hostsdeny(-1)))) {
1444                 reply_doserror(req, ERRSRV, ERRaccess);
1445                 return conn;
1446         }
1447
1448         smb_messages[type].fn(req);
1449         return req->conn;
1450 }
1451
1452 /****************************************************************************
1453  Construct a reply to the incoming packet.
1454 ****************************************************************************/
1455
1456 static void construct_reply(char *inbuf, int size, size_t unread_bytes, bool encrypted)
1457 {
1458         connection_struct *conn;
1459         struct smb_request *req;
1460
1461         chain_size = 0;
1462
1463         if (!(req = talloc(talloc_tos(), struct smb_request))) {
1464                 smb_panic("could not allocate smb_request");
1465         }
1466         init_smb_request(req, (uint8 *)inbuf, unread_bytes, encrypted);
1467         req->inbuf  = (uint8_t *)talloc_move(req, &inbuf);
1468
1469         conn = switch_message(req->cmd, req, size);
1470
1471         if (req->unread_bytes) {
1472                 /* writeX failed. drain socket. */
1473                 if (drain_socket(smbd_server_fd(), req->unread_bytes) !=
1474                                 req->unread_bytes) {
1475                         smb_panic("failed to drain pending bytes");
1476                 }
1477                 req->unread_bytes = 0;
1478         }
1479
1480         if (req->outbuf == NULL) {
1481                 return;
1482         }
1483
1484         if (CVAL(req->outbuf,0) == 0) {
1485                 show_msg((char *)req->outbuf);
1486         }
1487
1488         if (!srv_send_smb(smbd_server_fd(),
1489                         (char *)req->outbuf,
1490                         IS_CONN_ENCRYPTED(conn)||req->encrypted)) {
1491                 exit_server_cleanly("construct_reply: srv_send_smb failed.");
1492         }
1493
1494         TALLOC_FREE(req);
1495
1496         return;
1497 }
1498
1499 /****************************************************************************
1500  Process an smb from the client
1501 ****************************************************************************/
1502
1503 static void process_smb(struct smbd_server_connection *conn,
1504                         uint8_t *inbuf, size_t nread, size_t unread_bytes,
1505                         bool encrypted)
1506 {
1507         int msg_type = CVAL(inbuf,0);
1508
1509         DO_PROFILE_INC(smb_count);
1510
1511         DEBUG( 6, ( "got message type 0x%x of len 0x%x\n", msg_type,
1512                     smb_len(inbuf) ) );
1513         DEBUG( 3, ( "Transaction %d of length %d (%u toread)\n", trans_num,
1514                                 (int)nread,
1515                                 (unsigned int)unread_bytes ));
1516
1517         if (msg_type != 0) {
1518                 /*
1519                  * NetBIOS session request, keepalive, etc.
1520                  */
1521                 reply_special((char *)inbuf);
1522                 goto done;
1523         }
1524
1525         show_msg((char *)inbuf);
1526
1527         construct_reply((char *)inbuf,nread,unread_bytes,encrypted);
1528
1529         trans_num++;
1530
1531 done:
1532         conn->num_requests++;
1533
1534         /* The timeout_processing function isn't run nearly
1535            often enough to implement 'max log size' without
1536            overrunning the size of the file by many megabytes.
1537            This is especially true if we are running at debug
1538            level 10.  Checking every 50 SMBs is a nice
1539            tradeoff of performance vs log file size overrun. */
1540
1541         if ((conn->num_requests % 50) == 0 &&
1542             need_to_check_log_size()) {
1543                 change_to_root_user();
1544                 check_log_size();
1545         }
1546 }
1547
1548 /****************************************************************************
1549  Return a string containing the function name of a SMB command.
1550 ****************************************************************************/
1551
1552 const char *smb_fn_name(int type)
1553 {
1554         const char *unknown_name = "SMBunknown";
1555
1556         if (smb_messages[type].name == NULL)
1557                 return(unknown_name);
1558
1559         return(smb_messages[type].name);
1560 }
1561
1562 /****************************************************************************
1563  Helper functions for contruct_reply.
1564 ****************************************************************************/
1565
1566 void add_to_common_flags2(uint32 v)
1567 {
1568         common_flags2 |= v;
1569 }
1570
1571 void remove_from_common_flags2(uint32 v)
1572 {
1573         common_flags2 &= ~v;
1574 }
1575
1576 static void construct_reply_common(struct smb_request *req, const char *inbuf,
1577                                    char *outbuf)
1578 {
1579         srv_set_message(outbuf,0,0,false);
1580
1581         SCVAL(outbuf, smb_com, req->cmd);
1582         SIVAL(outbuf,smb_rcls,0);
1583         SCVAL(outbuf,smb_flg, FLAG_REPLY | (CVAL(inbuf,smb_flg) & FLAG_CASELESS_PATHNAMES));
1584         SSVAL(outbuf,smb_flg2,
1585                 (SVAL(inbuf,smb_flg2) & FLAGS2_UNICODE_STRINGS) |
1586                 common_flags2);
1587         memset(outbuf+smb_pidhigh,'\0',(smb_tid-smb_pidhigh));
1588
1589         SSVAL(outbuf,smb_tid,SVAL(inbuf,smb_tid));
1590         SSVAL(outbuf,smb_pid,SVAL(inbuf,smb_pid));
1591         SSVAL(outbuf,smb_uid,SVAL(inbuf,smb_uid));
1592         SSVAL(outbuf,smb_mid,SVAL(inbuf,smb_mid));
1593 }
1594
1595 void construct_reply_common_req(struct smb_request *req, char *outbuf)
1596 {
1597         construct_reply_common(req, (char *)req->inbuf, outbuf);
1598 }
1599
1600 /*
1601  * How many bytes have we already accumulated up to the current wct field
1602  * offset?
1603  */
1604
1605 size_t req_wct_ofs(struct smb_request *req)
1606 {
1607         size_t buf_size;
1608
1609         if (req->chain_outbuf == NULL) {
1610                 return smb_wct - 4;
1611         }
1612         buf_size = talloc_get_size(req->chain_outbuf);
1613         if ((buf_size % 4) != 0) {
1614                 buf_size += (4 - (buf_size % 4));
1615         }
1616         return buf_size - 4;
1617 }
1618
1619 /*
1620  * Hack around reply_nterror & friends not being aware of chained requests,
1621  * generating illegal (i.e. wct==0) chain replies.
1622  */
1623
1624 static void fixup_chain_error_packet(struct smb_request *req)
1625 {
1626         uint8_t *outbuf = req->outbuf;
1627         req->outbuf = NULL;
1628         reply_outbuf(req, 2, 0);
1629         memcpy(req->outbuf, outbuf, smb_wct);
1630         TALLOC_FREE(outbuf);
1631         SCVAL(req->outbuf, smb_vwv0, 0xff);
1632 }
1633
1634 /****************************************************************************
1635  Construct a chained reply and add it to the already made reply
1636 ****************************************************************************/
1637
1638 void chain_reply(struct smb_request *req)
1639 {
1640         size_t smblen = smb_len(req->inbuf);
1641         size_t already_used, length_needed;
1642         uint8_t chain_cmd;
1643         uint32_t chain_offset;  /* uint32_t to avoid overflow */
1644
1645         uint8_t wct;
1646         uint16_t *vwv;
1647         uint16_t buflen;
1648         uint8_t *buf;
1649
1650         if (IVAL(req->outbuf, smb_rcls) != 0) {
1651                 fixup_chain_error_packet(req);
1652         }
1653
1654         /*
1655          * Any of the AndX requests and replies have at least a wct of
1656          * 2. vwv[0] is the next command, vwv[1] is the offset from the
1657          * beginning of the SMB header to the next wct field.
1658          *
1659          * None of the AndX requests put anything valuable in vwv[0] and [1],
1660          * so we can overwrite it here to form the chain.
1661          */
1662
1663         if ((req->wct < 2) || (CVAL(req->outbuf, smb_wct) < 2)) {
1664                 goto error;
1665         }
1666
1667         /*
1668          * Here we assume that this is the end of the chain. For that we need
1669          * to set "next command" to 0xff and the offset to 0. If we later find
1670          * more commands in the chain, this will be overwritten again.
1671          */
1672
1673         SCVAL(req->outbuf, smb_vwv0, 0xff);
1674         SCVAL(req->outbuf, smb_vwv0+1, 0);
1675         SSVAL(req->outbuf, smb_vwv1, 0);
1676
1677         if (req->chain_outbuf == NULL) {
1678                 /*
1679                  * In req->chain_outbuf we collect all the replies. Start the
1680                  * chain by copying in the first reply.
1681                  *
1682                  * We do the realloc because later on we depend on
1683                  * talloc_get_size to determine the length of
1684                  * chain_outbuf. The reply_xxx routines might have
1685                  * over-allocated (reply_pipe_read_and_X used to be such an
1686                  * example).
1687                  */
1688                 req->chain_outbuf = TALLOC_REALLOC_ARRAY(
1689                         req, req->outbuf, uint8_t, smb_len(req->outbuf) + 4);
1690                 if (req->chain_outbuf == NULL) {
1691                         goto error;
1692                 }
1693                 req->outbuf = NULL;
1694         } else {
1695                 if (!smb_splice_chain(&req->chain_outbuf,
1696                                       CVAL(req->outbuf, smb_com),
1697                                       CVAL(req->outbuf, smb_wct),
1698                                       (uint16_t *)(req->outbuf + smb_vwv),
1699                                       0, smb_buflen(req->outbuf),
1700                                       (uint8_t *)smb_buf(req->outbuf))) {
1701                         goto error;
1702                 }
1703                 TALLOC_FREE(req->outbuf);
1704         }
1705
1706         /*
1707          * We use the old request's vwv field to grab the next chained command
1708          * and offset into the chained fields.
1709          */
1710
1711         chain_cmd = CVAL(req->vwv+0, 0);
1712         chain_offset = SVAL(req->vwv+1, 0);
1713
1714         if (chain_cmd == 0xff) {
1715                 /*
1716                  * End of chain, no more requests from the client. So ship the
1717                  * replies.
1718                  */
1719                 smb_setlen((char *)(req->chain_outbuf),
1720                            talloc_get_size(req->chain_outbuf) - 4);
1721                 if (!srv_send_smb(smbd_server_fd(), (char *)req->chain_outbuf,
1722                                   IS_CONN_ENCRYPTED(req->conn)
1723                                   ||req->encrypted)) {
1724                         exit_server_cleanly("chain_reply: srv_send_smb "
1725                                             "failed.");
1726                 }
1727                 return;
1728         }
1729
1730         /*
1731          * Check if the client tries to fool us. The request so far uses the
1732          * space to the end of the byte buffer in the request just
1733          * processed. The chain_offset can't point into that area. If that was
1734          * the case, we could end up with an endless processing of the chain,
1735          * we would always handle the same request.
1736          */
1737
1738         already_used = PTR_DIFF(req->buf+req->buflen, smb_base(req->inbuf));
1739         if (chain_offset < already_used) {
1740                 goto error;
1741         }
1742
1743         /*
1744          * Next check: Make sure the chain offset does not point beyond the
1745          * overall smb request length.
1746          */
1747
1748         length_needed = chain_offset+1; /* wct */
1749         if (length_needed > smblen) {
1750                 goto error;
1751         }
1752
1753         /*
1754          * Now comes the pointer magic. Goal here is to set up req->vwv and
1755          * req->buf correctly again to be able to call the subsequent
1756          * switch_message(). The chain offset (the former vwv[1]) points at
1757          * the new wct field.
1758          */
1759
1760         wct = CVAL(smb_base(req->inbuf), chain_offset);
1761
1762         /*
1763          * Next consistency check: Make the new vwv array fits in the overall
1764          * smb request.
1765          */
1766
1767         length_needed += (wct+1)*sizeof(uint16_t); /* vwv+buflen */
1768         if (length_needed > smblen) {
1769                 goto error;
1770         }
1771         vwv = (uint16_t *)(smb_base(req->inbuf) + chain_offset + 1);
1772
1773         /*
1774          * Now grab the new byte buffer....
1775          */
1776
1777         buflen = SVAL(vwv+wct, 0);
1778
1779         /*
1780          * .. and check that it fits.
1781          */
1782
1783         length_needed += buflen;
1784         if (length_needed > smblen) {
1785                 goto error;
1786         }
1787         buf = (uint8_t *)(vwv+wct+1);
1788
1789         req->cmd = chain_cmd;
1790         req->wct = wct;
1791         req->vwv = vwv;
1792         req->buflen = buflen;
1793         req->buf = buf;
1794
1795         switch_message(chain_cmd, req, smblen);
1796
1797         if (req->outbuf == NULL) {
1798                 /*
1799                  * This happens if the chained command has suspended itself or
1800                  * if it has called srv_send_smb() itself.
1801                  */
1802                 return;
1803         }
1804
1805         /*
1806          * We end up here if the chained command was not itself chained or
1807          * suspended, but for example a close() command. We now need to splice
1808          * the chained commands' outbuf into the already built up chain_outbuf
1809          * and ship the result.
1810          */
1811         goto done;
1812
1813  error:
1814         /*
1815          * We end up here if there's any error in the chain syntax. Report a
1816          * DOS error, just like Windows does.
1817          */
1818         reply_nterror(req, NT_STATUS_DOS(ERRSRV, ERRerror));
1819         fixup_chain_error_packet(req);
1820
1821  done:
1822         if (!smb_splice_chain(&req->chain_outbuf,
1823                               CVAL(req->outbuf, smb_com),
1824                               CVAL(req->outbuf, smb_wct),
1825                               (uint16_t *)(req->outbuf + smb_vwv),
1826                               0, smb_buflen(req->outbuf),
1827                               (uint8_t *)smb_buf(req->outbuf))) {
1828                 exit_server_cleanly("chain_reply: smb_splice_chain failed\n");
1829         }
1830         TALLOC_FREE(req->outbuf);
1831
1832         smb_setlen((char *)(req->chain_outbuf),
1833                    talloc_get_size(req->chain_outbuf) - 4);
1834
1835         show_msg((char *)(req->chain_outbuf));
1836
1837         if (!srv_send_smb(smbd_server_fd(), (char *)req->chain_outbuf,
1838                           IS_CONN_ENCRYPTED(req->conn)||req->encrypted)) {
1839                 exit_server_cleanly("construct_reply: srv_send_smb failed.");
1840         }
1841 }
1842
1843 /****************************************************************************
1844  Check if services need reloading.
1845 ****************************************************************************/
1846
1847 void check_reload(time_t t)
1848 {
1849         time_t printcap_cache_time = (time_t)lp_printcap_cache_time();
1850
1851         if(last_smb_conf_reload_time == 0) {
1852                 last_smb_conf_reload_time = t;
1853                 /* Our printing subsystem might not be ready at smbd start up.
1854                    Then no printer is available till the first printers check
1855                    is performed.  A lower initial interval circumvents this. */
1856                 if ( printcap_cache_time > 60 )
1857                         last_printer_reload_time = t - printcap_cache_time + 60;
1858                 else
1859                         last_printer_reload_time = t;
1860         }
1861
1862         if (mypid != getpid()) { /* First time or fork happened meanwhile */
1863                 /* randomize over 60 second the printcap reload to avoid all
1864                  * process hitting cupsd at the same time */
1865                 int time_range = 60;
1866
1867                 last_printer_reload_time += random() % time_range;
1868                 mypid = getpid();
1869         }
1870
1871         if (t >= last_smb_conf_reload_time+SMBD_RELOAD_CHECK) {
1872                 reload_services(True);
1873                 last_smb_conf_reload_time = t;
1874         }
1875
1876         /* 'printcap cache time = 0' disable the feature */
1877
1878         if ( printcap_cache_time != 0 )
1879         {
1880                 /* see if it's time to reload or if the clock has been set back */
1881
1882                 if ( (t >= last_printer_reload_time+printcap_cache_time)
1883                         || (t-last_printer_reload_time  < 0) )
1884                 {
1885                         DEBUG( 3,( "Printcap cache time expired.\n"));
1886                         reload_printers();
1887                         last_printer_reload_time = t;
1888                 }
1889         }
1890 }
1891
1892 static void smbd_server_connection_write_handler(struct smbd_server_connection *conn)
1893 {
1894         /* TODO: make write nonblocking */
1895 }
1896
1897 static void smbd_server_connection_read_handler(struct smbd_server_connection *conn)
1898 {
1899         uint8_t *inbuf = NULL;
1900         size_t inbuf_len = 0;
1901         size_t unread_bytes = 0;
1902         bool encrypted = false;
1903         TALLOC_CTX *mem_ctx = talloc_tos();
1904         NTSTATUS status;
1905
1906         /* TODO: make this completely nonblocking */
1907
1908         status = receive_smb_talloc(mem_ctx, smbd_server_fd(),
1909                                     (char **)(void *)&inbuf,
1910                                     0, /* timeout */
1911                                     &unread_bytes,
1912                                     &encrypted,
1913                                     &inbuf_len);
1914         if (NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
1915                 goto process;
1916         }
1917         if (NT_STATUS_IS_ERR(status)) {
1918                 exit_server_cleanly("failed to receive smb request");
1919         }
1920         if (!NT_STATUS_IS_OK(status)) {
1921                 return;
1922         }
1923
1924 process:
1925         process_smb(conn, inbuf, inbuf_len, unread_bytes, encrypted);
1926 }
1927
1928 static void smbd_server_connection_handler(struct event_context *ev,
1929                                            struct fd_event *fde,
1930                                            uint16_t flags,
1931                                            void *private_data)
1932 {
1933         struct smbd_server_connection *conn = talloc_get_type(private_data,
1934                                               struct smbd_server_connection);
1935
1936         if (flags & EVENT_FD_WRITE) {
1937                 smbd_server_connection_write_handler(conn);
1938         } else if (flags & EVENT_FD_READ) {
1939                 smbd_server_connection_read_handler(conn);
1940         }
1941 }
1942
1943
1944 /****************************************************************************
1945 received when we should release a specific IP
1946 ****************************************************************************/
1947 static void release_ip(const char *ip, void *priv)
1948 {
1949         char addr[INET6_ADDRSTRLEN];
1950
1951         if (strcmp(client_socket_addr(get_client_fd(),addr,sizeof(addr)), ip) == 0) {
1952                 /* we can't afford to do a clean exit - that involves
1953                    database writes, which would potentially mean we
1954                    are still running after the failover has finished -
1955                    we have to get rid of this process ID straight
1956                    away */
1957                 DEBUG(0,("Got release IP message for our IP %s - exiting immediately\n",
1958                         ip));
1959                 /* note we must exit with non-zero status so the unclean handler gets
1960                    called in the parent, so that the brl database is tickled */
1961                 _exit(1);
1962         }
1963 }
1964
1965 static void msg_release_ip(struct messaging_context *msg_ctx, void *private_data,
1966                            uint32_t msg_type, struct server_id server_id, DATA_BLOB *data)
1967 {
1968         release_ip((char *)data->data, NULL);
1969 }
1970
1971 #ifdef CLUSTER_SUPPORT
1972 static int client_get_tcp_info(struct sockaddr_storage *server,
1973                                struct sockaddr_storage *client)
1974 {
1975         socklen_t length;
1976         if (server_fd == -1) {
1977                 return -1;
1978         }
1979         length = sizeof(*server);
1980         if (getsockname(server_fd, (struct sockaddr *)server, &length) != 0) {
1981                 return -1;
1982         }
1983         length = sizeof(*client);
1984         if (getpeername(server_fd, (struct sockaddr *)client, &length) != 0) {
1985                 return -1;
1986         }
1987         return 0;
1988 }
1989 #endif
1990
1991 /*
1992  * Send keepalive packets to our client
1993  */
1994 static bool keepalive_fn(const struct timeval *now, void *private_data)
1995 {
1996         if (!send_keepalive(smbd_server_fd())) {
1997                 DEBUG( 2, ( "Keepalive failed - exiting.\n" ) );
1998                 return False;
1999         }
2000         return True;
2001 }
2002
2003 /*
2004  * Do the recurring check if we're idle
2005  */
2006 static bool deadtime_fn(const struct timeval *now, void *private_data)
2007 {
2008         if ((conn_num_open() == 0)
2009             || (conn_idle_all(now->tv_sec))) {
2010                 DEBUG( 2, ( "Closing idle connection\n" ) );
2011                 messaging_send(smbd_messaging_context(), procid_self(),
2012                                MSG_SHUTDOWN, &data_blob_null);
2013                 return False;
2014         }
2015
2016         return True;
2017 }
2018
2019 /*
2020  * Do the recurring log file and smb.conf reload checks.
2021  */
2022
2023 static bool housekeeping_fn(const struct timeval *now, void *private_data)
2024 {
2025         change_to_root_user();
2026
2027         /* update printer queue caches if necessary */
2028         update_monitored_printq_cache();
2029
2030         /* check if we need to reload services */
2031         check_reload(time(NULL));
2032
2033         /* Change machine password if neccessary. */
2034         attempt_machine_password_change();
2035
2036         /*
2037          * Force a log file check.
2038          */
2039         force_check_log_size();
2040         check_log_size();
2041         return true;
2042 }
2043
2044 /****************************************************************************
2045  Process commands from the client
2046 ****************************************************************************/
2047
2048 void smbd_process(void)
2049 {
2050         TALLOC_CTX *frame = talloc_stackframe();
2051         char remaddr[INET6_ADDRSTRLEN];
2052
2053         smbd_server_conn = talloc_zero(smbd_event_context(), struct smbd_server_connection);
2054         if (!smbd_server_conn) {
2055                 exit_server("failed to create smbd_server_connection");
2056         }
2057
2058         /* Ensure child is set to blocking mode */
2059         set_blocking(smbd_server_fd(),True);
2060
2061         set_socket_options(smbd_server_fd(),"SO_KEEPALIVE");
2062         set_socket_options(smbd_server_fd(), lp_socket_options());
2063
2064         /* this is needed so that we get decent entries
2065            in smbstatus for port 445 connects */
2066         set_remote_machine_name(get_peer_addr(smbd_server_fd(),
2067                                               remaddr,
2068                                               sizeof(remaddr)),
2069                                               false);
2070         reload_services(true);
2071
2072         /*
2073          * Before the first packet, check the global hosts allow/ hosts deny
2074          * parameters before doing any parsing of packets passed to us by the
2075          * client. This prevents attacks on our parsing code from hosts not in
2076          * the hosts allow list.
2077          */
2078
2079         if (!check_access(smbd_server_fd(), lp_hostsallow(-1),
2080                           lp_hostsdeny(-1))) {
2081                 char addr[INET6_ADDRSTRLEN];
2082
2083                 /*
2084                  * send a negative session response "not listening on calling
2085                  * name"
2086                  */
2087                 unsigned char buf[5] = {0x83, 0, 0, 1, 0x81};
2088                 DEBUG( 1, ("Connection denied from %s\n",
2089                            client_addr(get_client_fd(),addr,sizeof(addr)) ) );
2090                 (void)srv_send_smb(smbd_server_fd(),(char *)buf,false);
2091                 exit_server_cleanly("connection denied");
2092         }
2093
2094         static_init_rpc;
2095
2096         init_modules();
2097
2098         if (!init_account_policy()) {
2099                 exit_server("Could not open account policy tdb.\n");
2100         }
2101
2102         if (*lp_rootdir()) {
2103                 if (chroot(lp_rootdir()) != 0) {
2104                         DEBUG(0,("Failed changed root to %s\n", lp_rootdir()));
2105                         exit_server("Failed to chroot()");
2106                 }
2107                 DEBUG(0,("Changed root to %s\n", lp_rootdir()));
2108         }
2109
2110         /* Setup oplocks */
2111         if (!init_oplocks(smbd_messaging_context()))
2112                 exit_server("Failed to init oplocks");
2113
2114         /* Setup aio signal handler. */
2115         initialize_async_io_handler();
2116
2117         /* register our message handlers */
2118         messaging_register(smbd_messaging_context(), NULL,
2119                            MSG_SMB_FORCE_TDIS, msg_force_tdis);
2120         messaging_register(smbd_messaging_context(), NULL,
2121                            MSG_SMB_RELEASE_IP, msg_release_ip);
2122         messaging_register(smbd_messaging_context(), NULL,
2123                            MSG_SMB_CLOSE_FILE, msg_close_file);
2124
2125         if ((lp_keepalive() != 0)
2126             && !(event_add_idle(smbd_event_context(), NULL,
2127                                 timeval_set(lp_keepalive(), 0),
2128                                 "keepalive", keepalive_fn,
2129                                 NULL))) {
2130                 DEBUG(0, ("Could not add keepalive event\n"));
2131                 exit(1);
2132         }
2133
2134         if (!(event_add_idle(smbd_event_context(), NULL,
2135                              timeval_set(IDLE_CLOSED_TIMEOUT, 0),
2136                              "deadtime", deadtime_fn, NULL))) {
2137                 DEBUG(0, ("Could not add deadtime event\n"));
2138                 exit(1);
2139         }
2140
2141         if (!(event_add_idle(smbd_event_context(), NULL,
2142                              timeval_set(SMBD_SELECT_TIMEOUT, 0),
2143                              "housekeeping", housekeeping_fn, NULL))) {
2144                 DEBUG(0, ("Could not add housekeeping event\n"));
2145                 exit(1);
2146         }
2147
2148 #ifdef CLUSTER_SUPPORT
2149
2150         if (lp_clustering()) {
2151                 /*
2152                  * We need to tell ctdb about our client's TCP
2153                  * connection, so that for failover ctdbd can send
2154                  * tickle acks, triggering a reconnection by the
2155                  * client.
2156                  */
2157
2158                 struct sockaddr_storage srv, clnt;
2159
2160                 if (client_get_tcp_info(&srv, &clnt) == 0) {
2161
2162                         NTSTATUS status;
2163
2164                         status = ctdbd_register_ips(
2165                                 messaging_ctdbd_connection(),
2166                                 &srv, &clnt, release_ip, NULL);
2167
2168                         if (!NT_STATUS_IS_OK(status)) {
2169                                 DEBUG(0, ("ctdbd_register_ips failed: %s\n",
2170                                           nt_errstr(status)));
2171                         }
2172                 } else
2173                 {
2174                         DEBUG(0,("Unable to get tcp info for "
2175                                  "CTDB_CONTROL_TCP_CLIENT: %s\n",
2176                                  strerror(errno)));
2177                 }
2178         }
2179
2180 #endif
2181
2182         max_recv = MIN(lp_maxxmit(),BUFFER_SIZE);
2183
2184         smbd_server_conn->fde = event_add_fd(smbd_event_context(),
2185                                              smbd_server_conn,
2186                                              smbd_server_fd(),
2187                                              EVENT_FD_READ,
2188                                              smbd_server_connection_handler,
2189                                              smbd_server_conn);
2190         if (!smbd_server_conn->fde) {
2191                 exit_server("failed to create smbd_server_connection fde");
2192         }
2193
2194         TALLOC_FREE(frame);
2195
2196         while (True) {
2197                 NTSTATUS status;
2198
2199                 frame = talloc_stackframe_pool(8192);
2200
2201                 errno = 0;
2202
2203                 status = smbd_server_connection_loop_once(smbd_server_conn);
2204                 if (!NT_STATUS_EQUAL(status, NT_STATUS_RETRY) &&
2205                     !NT_STATUS_IS_OK(status)) {
2206                         DEBUG(3, ("smbd_server_connection_loop_once failed: %s,"
2207                                   " exiting\n", nt_errstr(status)));
2208                         break;
2209                 }
2210
2211                 TALLOC_FREE(frame);
2212         }
2213
2214         exit_server_cleanly(NULL);
2215 }