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 #include "../librpc/gen_ndr/srv_dfs.h"
  24 #include "../librpc/gen_ndr/srv_dssetup.h"
  25 #include "../librpc/gen_ndr/srv_echo.h"
  26 #include "../librpc/gen_ndr/srv_eventlog.h"
  27 #include "../librpc/gen_ndr/srv_initshutdown.h"
  28 #include "../librpc/gen_ndr/srv_lsa.h"
  29 #include "../librpc/gen_ndr/srv_netlogon.h"
  30 #include "../librpc/gen_ndr/srv_ntsvcs.h"
  31 #include "../librpc/gen_ndr/srv_samr.h"
  32 #include "../librpc/gen_ndr/srv_spoolss.h"
  33 #include "../librpc/gen_ndr/srv_srvsvc.h"
  34 #include "../librpc/gen_ndr/srv_svcctl.h"
  35 #include "../librpc/gen_ndr/srv_winreg.h"
  36 #include "../librpc/gen_ndr/srv_wkssvc.h"
  37
  38 extern bool global_machine_password_needs_changing;
  39
  40 static void construct_reply_common(struct smb_request *req, const char *inbuf,
  41                                    char *outbuf);
  42
  43 /* Accessor function for smb_read_error for smbd functions. */
  44
  45 /****************************************************************************
  46  Send an smb to a fd.
  47 ****************************************************************************/
  48
  49 bool srv_send_smb(int fd, char *buffer,
  50                   bool do_signing, uint32_t seqnum,
  51                   bool do_encrypt,
  52                   struct smb_perfcount_data *pcd)
  53 {
  54         size_t len = 0;
  55         size_t nwritten=0;
  56         ssize_t ret;
  57         char *buf_out = buffer;
  58
  59         if (do_signing) {
  60                 /* Sign the outgoing packet if required. */
  61                 srv_calculate_sign_mac(smbd_server_conn, buf_out, seqnum);
  62         }
  63
  64         if (do_encrypt) {
  65                 NTSTATUS status = srv_encrypt_buffer(buffer, &buf_out);
  66                 if (!NT_STATUS_IS_OK(status)) {
  67                         DEBUG(0, ("send_smb: SMB encryption failed "
  68                                 "on outgoing packet! Error %s\n",
  69                                 nt_errstr(status) ));
  70                         goto out;
  71                 }
  72         }
  73
  74         len = smb_len(buf_out) + 4;
  75
  76         ret = write_data(fd,buf_out+nwritten,len - nwritten);
  77         if (ret <= 0) {
  78                 DEBUG(0,("Error writing %d bytes to client. %d. (%s)\n",
  79                          (int)len,(int)ret, strerror(errno) ));
  80                 srv_free_enc_buffer(buf_out);
  81                 goto out;
  82         }
  83
  84         SMB_PERFCOUNT_SET_MSGLEN_OUT(pcd, len);
  85         srv_free_enc_buffer(buf_out);
  86 out:
  87         SMB_PERFCOUNT_END(pcd);
  88         return true;
  89 }
  90
  91 /*******************************************************************
  92  Setup the word count and byte count for a smb message.
  93 ********************************************************************/
  94
  95 int srv_set_message(char *buf,
  96                         int num_words,
  97                         int num_bytes,
  98                         bool zero)
  99 {
 100         if (zero && (num_words || num_bytes)) {
 101                 memset(buf + smb_size,'\0',num_words*2 + num_bytes);
 102         }
 103         SCVAL(buf,smb_wct,num_words);
 104         SSVAL(buf,smb_vwv + num_words*SIZEOFWORD,num_bytes);
 105         smb_setlen(buf,(smb_size + num_words*2 + num_bytes - 4));
 106         return (smb_size + num_words*2 + num_bytes);
 107 }
 108
 109 static bool valid_smb_header(const uint8_t *inbuf)
 110 {
 111         if (is_encrypted_packet(inbuf)) {
 112                 return true;
 113         }
 114         /*
 115          * This used to be (strncmp(smb_base(inbuf),"\377SMB",4) == 0)
 116          * but it just looks weird to call strncmp for this one.
 117          */
 118         return (IVAL(smb_base(inbuf), 0) == 0x424D53FF);
 119 }
 120
 121 /* Socket functions for smbd packet processing. */
 122
 123 static bool valid_packet_size(size_t len)
 124 {
 125         /*
 126          * A WRITEX with CAP_LARGE_WRITEX can be 64k worth of data plus 65 bytes
 127          * of header. Don't print the error if this fits.... JRA.
 128          */
 129
 130         if (len > (BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE)) {
 131                 DEBUG(0,("Invalid packet length! (%lu bytes).\n",
 132                                         (unsigned long)len));
 133                 return false;
 134         }
 135         return true;
 136 }
 137
 138 static NTSTATUS read_packet_remainder(int fd, char *buffer,
 139                                       unsigned int timeout, ssize_t len)
 140 {
 141         if (len <= 0) {
 142                 return NT_STATUS_OK;
 143         }
 144
 145         return read_fd_with_timeout(fd, buffer, len, len, timeout, NULL);
 146 }
 147
 148 /****************************************************************************
 149  Attempt a zerocopy writeX read. We know here that len > smb_size-4
 150 ****************************************************************************/
 151
 152 /*
 153  * Unfortunately, earlier versions of smbclient/libsmbclient
 154  * don't send this "standard" writeX header. I've fixed this
 155  * for 3.2 but we'll use the old method with earlier versions.
 156  * Windows and CIFSFS at least use this standard size. Not
 157  * sure about MacOSX.
 158  */
 159
 160 #define STANDARD_WRITE_AND_X_HEADER_SIZE (smb_size - 4 + /* basic header */ \
 161                                 (2*14) + /* word count (including bcc) */ \
 162                                 1 /* pad byte */)
 163
 164 static NTSTATUS receive_smb_raw_talloc_partial_read(TALLOC_CTX *mem_ctx,
 165                                                     const char lenbuf[4],
 166                                                     int fd, char **buffer,
 167                                                     unsigned int timeout,
 168                                                     size_t *p_unread,
 169                                                     size_t *len_ret)
 170 {
 171         /* Size of a WRITEX call (+4 byte len). */
 172         char writeX_header[4 + STANDARD_WRITE_AND_X_HEADER_SIZE];
 173         ssize_t len = smb_len_large(lenbuf); /* Could be a UNIX large writeX. */
 174         ssize_t toread;
 175         NTSTATUS status;
 176
 177         memcpy(writeX_header, lenbuf, 4);
 178
 179         status = read_fd_with_timeout(
 180                 fd, writeX_header + 4,
 181                 STANDARD_WRITE_AND_X_HEADER_SIZE,
 182                 STANDARD_WRITE_AND_X_HEADER_SIZE,
 183                 timeout, NULL);
 184
 185         if (!NT_STATUS_IS_OK(status)) {
 186                 return status;
 187         }
 188
 189         /*
 190          * Ok - now try and see if this is a possible
 191          * valid writeX call.
 192          */
 193
 194         if (is_valid_writeX_buffer((uint8_t *)writeX_header)) {
 195                 /*
 196                  * If the data offset is beyond what
 197                  * we've read, drain the extra bytes.
 198                  */
 199                 uint16_t doff = SVAL(writeX_header,smb_vwv11);
 200                 ssize_t newlen;
 201
 202                 if (doff > STANDARD_WRITE_AND_X_HEADER_SIZE) {
 203                         size_t drain = doff - STANDARD_WRITE_AND_X_HEADER_SIZE;
 204                         if (drain_socket(smbd_server_fd(), drain) != drain) {
 205                                 smb_panic("receive_smb_raw_talloc_partial_read:"
 206                                         " failed to drain pending bytes");
 207                         }
 208                 } else {
 209                         doff = STANDARD_WRITE_AND_X_HEADER_SIZE;
 210                 }
 211
 212                 /* Spoof down the length and null out the bcc. */
 213                 set_message_bcc(writeX_header, 0);
 214                 newlen = smb_len(writeX_header);
 215
 216                 /* Copy the header we've written. */
 217
 218                 *buffer = (char *)TALLOC_MEMDUP(mem_ctx,
 219                                 writeX_header,
 220                                 sizeof(writeX_header));
 221
 222                 if (*buffer == NULL) {
 223                         DEBUG(0, ("Could not allocate inbuf of length %d\n",
 224                                   (int)sizeof(writeX_header)));
 225                         return NT_STATUS_NO_MEMORY;
 226                 }
 227
 228                 /* Work out the remaining bytes. */
 229                 *p_unread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
 230                 *len_ret = newlen + 4;
 231                 return NT_STATUS_OK;
 232         }
 233
 234         if (!valid_packet_size(len)) {
 235                 return NT_STATUS_INVALID_PARAMETER;
 236         }
 237
 238         /*
 239          * Not a valid writeX call. Just do the standard
 240          * talloc and return.
 241          */
 242
 243         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
 244
 245         if (*buffer == NULL) {
 246                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
 247                           (int)len+4));
 248                 return NT_STATUS_NO_MEMORY;
 249         }
 250
 251         /* Copy in what we already read. */
 252         memcpy(*buffer,
 253                 writeX_header,
 254                 4 + STANDARD_WRITE_AND_X_HEADER_SIZE);
 255         toread = len - STANDARD_WRITE_AND_X_HEADER_SIZE;
 256
 257         if(toread > 0) {
 258                 status = read_packet_remainder(
 259                         fd, (*buffer) + 4 + STANDARD_WRITE_AND_X_HEADER_SIZE,
 260                         timeout, toread);
 261
 262                 if (!NT_STATUS_IS_OK(status)) {
 263                         DEBUG(10, ("receive_smb_raw_talloc_partial_read: %s\n",
 264                                    nt_errstr(status)));
 265                         return status;
 266                 }
 267         }
 268
 269         *len_ret = len + 4;
 270         return NT_STATUS_OK;
 271 }
 272
 273 static NTSTATUS receive_smb_raw_talloc(TALLOC_CTX *mem_ctx, int fd,
 274                                        char **buffer, unsigned int timeout,
 275                                        size_t *p_unread, size_t *plen)
 276 {
 277         char lenbuf[4];
 278         size_t len;
 279         int min_recv_size = lp_min_receive_file_size();
 280         NTSTATUS status;
 281
 282         *p_unread = 0;
 283
 284         status = read_smb_length_return_keepalive(fd, lenbuf, timeout, &len);
 285         if (!NT_STATUS_IS_OK(status)) {
 286                 DEBUG(10, ("receive_smb_raw: %s\n", nt_errstr(status)));
 287                 return status;
 288         }
 289
 290         if (CVAL(lenbuf,0) == 0 && min_recv_size &&
 291             (smb_len_large(lenbuf) > /* Could be a UNIX large writeX. */
 292                 (min_recv_size + STANDARD_WRITE_AND_X_HEADER_SIZE)) &&
 293             !srv_is_signing_active(smbd_server_conn)) {
 294
 295                 return receive_smb_raw_talloc_partial_read(
 296                         mem_ctx, lenbuf, fd, buffer, timeout, p_unread, plen);
 297         }
 298
 299         if (!valid_packet_size(len)) {
 300                 return NT_STATUS_INVALID_PARAMETER;
 301         }
 302
 303         /*
 304          * The +4 here can't wrap, we've checked the length above already.
 305          */
 306
 307         *buffer = TALLOC_ARRAY(mem_ctx, char, len+4);
 308
 309         if (*buffer == NULL) {
 310                 DEBUG(0, ("Could not allocate inbuf of length %d\n",
 311                           (int)len+4));
 312                 return NT_STATUS_NO_MEMORY;
 313         }
 314
 315         memcpy(*buffer, lenbuf, sizeof(lenbuf));
 316
 317         status = read_packet_remainder(fd, (*buffer)+4, timeout, len);
 318         if (!NT_STATUS_IS_OK(status)) {
 319                 return status;
 320         }
 321
 322         *plen = len + 4;
 323         return NT_STATUS_OK;
 324 }
 325
 326 static NTSTATUS receive_smb_talloc(TALLOC_CTX *mem_ctx, int fd,
 327                                    char **buffer, unsigned int timeout,
 328                                    size_t *p_unread, bool *p_encrypted,
 329                                    size_t *p_len,
 330                                    uint32_t *seqnum)
 331 {
 332         size_t len = 0;
 333         NTSTATUS status;
 334
 335         *p_encrypted = false;
 336
 337         status = receive_smb_raw_talloc(mem_ctx, fd, buffer, timeout,
 338                                         p_unread, &len);
 339         if (!NT_STATUS_IS_OK(status)) {
 340                 return status;
 341         }
 342
 343         if (is_encrypted_packet((uint8_t *)*buffer)) {
 344                 status = srv_decrypt_buffer(*buffer);
 345                 if (!NT_STATUS_IS_OK(status)) {
 346                         DEBUG(0, ("receive_smb_talloc: SMB decryption failed on "
 347                                 "incoming packet! Error %s\n",
 348                                 nt_errstr(status) ));
 349                         return status;
 350                 }
 351                 *p_encrypted = true;
 352         }
 353
 354         /* Check the incoming SMB signature. */
 355         if (!srv_check_sign_mac(smbd_server_conn, *buffer, seqnum)) {
 356                 DEBUG(0, ("receive_smb: SMB Signature verification failed on "
 357                           "incoming packet!\n"));
 358                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
 359         }
 360
 361         *p_len = len;
 362         return NT_STATUS_OK;
 363 }
 364
 365 /*
 366  * Initialize a struct smb_request from an inbuf
 367  */
 368
 369 void init_smb_request(struct smb_request *req,
 370                         const uint8 *inbuf,
 371                         size_t unread_bytes,
 372                         bool encrypted)
 373 {
 374         struct smbd_server_connection *sconn = smbd_server_conn;
 375         size_t req_size = smb_len(inbuf) + 4;
 376         /* Ensure we have at least smb_size bytes. */
 377         if (req_size < smb_size) {
 378                 DEBUG(0,("init_smb_request: invalid request size %u\n",
 379                         (unsigned int)req_size ));
 380                 exit_server_cleanly("Invalid SMB request");
 381         }
 382         req->cmd    = CVAL(inbuf, smb_com);
 383         req->flags2 = SVAL(inbuf, smb_flg2);
 384         req->smbpid = SVAL(inbuf, smb_pid);
 385         req->mid    = SVAL(inbuf, smb_mid);
 386         req->seqnum = 0;
 387         req->vuid   = SVAL(inbuf, smb_uid);
 388         req->tid    = SVAL(inbuf, smb_tid);
 389         req->wct    = CVAL(inbuf, smb_wct);
 390         req->vwv    = (uint16_t *)(inbuf+smb_vwv);
 391         req->buflen = smb_buflen(inbuf);
 392         req->buf    = (const uint8_t *)smb_buf(inbuf);
 393         req->unread_bytes = unread_bytes;
 394         req->encrypted = encrypted;
 395         req->conn = conn_find(sconn,req->tid);
 396         req->chain_fsp = NULL;
 397         req->chain_outbuf = NULL;
 398         req->done = false;
 399         smb_init_perfcount_data(&req->pcd);
 400
 401         /* Ensure we have at least wct words and 2 bytes of bcc. */
 402         if (smb_size + req->wct*2 > req_size) {
 403                 DEBUG(0,("init_smb_request: invalid wct number %u (size %u)\n",
 404                         (unsigned int)req->wct,
 405                         (unsigned int)req_size));
 406                 exit_server_cleanly("Invalid SMB request");
 407         }
 408         /* Ensure bcc is correct. */
 409         if (((uint8 *)smb_buf(inbuf)) + req->buflen > inbuf + req_size) {
 410                 DEBUG(0,("init_smb_request: invalid bcc number %u "
 411                         "(wct = %u, size %u)\n",
 412                         (unsigned int)req->buflen,
 413                         (unsigned int)req->wct,
 414                         (unsigned int)req_size));
 415                 exit_server_cleanly("Invalid SMB request");
 416         }
 417
 418         req->outbuf = NULL;
 419 }
 420
 421 static void process_smb(struct smbd_server_connection *conn,
 422                         uint8_t *inbuf, size_t nread, size_t unread_bytes,
 423                         uint32_t seqnum, bool encrypted,
 424                         struct smb_perfcount_data *deferred_pcd);
 425
 426 static void smbd_deferred_open_timer(struct event_context *ev,
 427                                      struct timed_event *te,
 428                                      struct timeval _tval,
 429                                      void *private_data)
 430 {
 431         struct pending_message_list *msg = talloc_get_type(private_data,
 432                                            struct pending_message_list);
 433         TALLOC_CTX *mem_ctx = talloc_tos();
 434         uint16_t mid = SVAL(msg->buf.data,smb_mid);
 435         uint8_t *inbuf;
 436
 437         inbuf = (uint8_t *)talloc_memdup(mem_ctx, msg->buf.data,
 438                                          msg->buf.length);
 439         if (inbuf == NULL) {
 440                 exit_server("smbd_deferred_open_timer: talloc failed\n");
 441                 return;
 442         }
 443
 444         /* We leave this message on the queue so the open code can
 445            know this is a retry. */
 446         DEBUG(5,("smbd_deferred_open_timer: trigger mid %u.\n",
 447                 (unsigned int)mid ));
 448
 449         /* Mark the message as processed so this is not
 450          * re-processed in error. */
 451         msg->processed = true;
 452
 453         process_smb(smbd_server_conn, inbuf,
 454                     msg->buf.length, 0,
 455                     msg->seqnum, msg->encrypted, &msg->pcd);
 456
 457         /* If it's still there and was processed, remove it. */
 458         msg = get_open_deferred_message(mid);
 459         if (msg && msg->processed) {
 460                 remove_deferred_open_smb_message(mid);
 461         }
 462 }
 463
 464 /****************************************************************************
 465  Function to push a message onto the tail of a linked list of smb messages ready
 466  for processing.
 467 ****************************************************************************/
 468
 469 static bool push_queued_message(struct smb_request *req,
 470                                 struct timeval request_time,
 471                                 struct timeval end_time,
 472                                 char *private_data, size_t private_len)
 473 {
 474         int msg_len = smb_len(req->inbuf) + 4;
 475         struct pending_message_list *msg;
 476
 477         msg = TALLOC_ZERO_P(NULL, struct pending_message_list);
 478
 479         if(msg == NULL) {
 480                 DEBUG(0,("push_message: malloc fail (1)\n"));
 481                 return False;
 482         }
 483
 484         msg->buf = data_blob_talloc(msg, req->inbuf, msg_len);
 485         if(msg->buf.data == NULL) {
 486                 DEBUG(0,("push_message: malloc fail (2)\n"));
 487                 TALLOC_FREE(msg);
 488                 return False;
 489         }
 490
 491         msg->request_time = request_time;
 492         msg->seqnum = req->seqnum;
 493         msg->encrypted = req->encrypted;
 494         msg->processed = false;
 495         SMB_PERFCOUNT_DEFER_OP(&req->pcd, &msg->pcd);
 496
 497         if (private_data) {
 498                 msg->private_data = data_blob_talloc(msg, private_data,
 499                                                      private_len);
 500                 if (msg->private_data.data == NULL) {
 501                         DEBUG(0,("push_message: malloc fail (3)\n"));
 502                         TALLOC_FREE(msg);
 503                         return False;
 504                 }
 505         }
 506
 507         msg->te = event_add_timed(smbd_event_context(),
 508                                   msg,
 509                                   end_time,
 510                                   smbd_deferred_open_timer,
 511                                   msg);
 512         if (!msg->te) {
 513                 DEBUG(0,("push_message: event_add_timed failed\n"));
 514                 TALLOC_FREE(msg);
 515                 return false;
 516         }
 517
 518         DLIST_ADD_END(deferred_open_queue, msg, struct pending_message_list *);
 519
 520         DEBUG(10,("push_message: pushed message length %u on "
 521                   "deferred_open_queue\n", (unsigned int)msg_len));
 522
 523         return True;
 524 }
 525
 526 /****************************************************************************
 527  Function to delete a sharing violation open message by mid.
 528 ****************************************************************************/
 529
 530 void remove_deferred_open_smb_message(uint16 mid)
 531 {
 532         struct pending_message_list *pml;
 533
 534         for (pml = deferred_open_queue; pml; pml = pml->next) {
 535                 if (mid == SVAL(pml->buf.data,smb_mid)) {
 536                         DEBUG(10,("remove_deferred_open_smb_message: "
 537                                   "deleting mid %u len %u\n",
 538                                   (unsigned int)mid,
 539                                   (unsigned int)pml->buf.length ));
 540                         DLIST_REMOVE(deferred_open_queue, pml);
 541                         TALLOC_FREE(pml);
 542                         return;
 543                 }
 544         }
 545 }
 546
 547 /****************************************************************************
 548  Move a sharing violation open retry message to the front of the list and
 549  schedule it for immediate processing.
 550 ****************************************************************************/
 551
 552 void schedule_deferred_open_smb_message(uint16 mid)
 553 {
 554         struct pending_message_list *pml;
 555         int i = 0;
 556
 557         for (pml = deferred_open_queue; pml; pml = pml->next) {
 558                 uint16 msg_mid = SVAL(pml->buf.data,smb_mid);
 559
 560                 DEBUG(10,("schedule_deferred_open_smb_message: [%d] msg_mid = %u\n", i++,
 561                         (unsigned int)msg_mid ));
 562
 563                 if (mid == msg_mid) {
 564                         struct timed_event *te;
 565
 566                         if (pml->processed) {
 567                                 /* A processed message should not be
 568                                  * rescheduled. */
 569                                 DEBUG(0,("schedule_deferred_open_smb_message: LOGIC ERROR "
 570                                         "message mid %u was already processed\n",
 571                                         msg_mid ));
 572                                 continue;
 573                         }
 574
 575                         DEBUG(10,("schedule_deferred_open_smb_message: scheduling mid %u\n",
 576                                 mid ));
 577
 578                         te = event_add_timed(smbd_event_context(),
 579                                              pml,
 580                                              timeval_zero(),
 581                                              smbd_deferred_open_timer,
 582                                              pml);
 583                         if (!te) {
 584                                 DEBUG(10,("schedule_deferred_open_smb_message: "
 585                                           "event_add_timed() failed, skipping mid %u\n",
 586                                           mid ));
 587                         }
 588
 589                         TALLOC_FREE(pml->te);
 590                         pml->te = te;
 591                         DLIST_PROMOTE(deferred_open_queue, pml);
 592                         return;
 593                 }
 594         }
 595
 596         DEBUG(10,("schedule_deferred_open_smb_message: failed to find message mid %u\n",
 597                 mid ));
 598 }
 599
 600 /****************************************************************************
 601  Return true if this mid is on the deferred queue and was not yet processed.
 602 ****************************************************************************/
 603
 604 bool open_was_deferred(uint16 mid)
 605 {
 606         struct pending_message_list *pml;
 607
 608         for (pml = deferred_open_queue; pml; pml = pml->next) {
 609                 if (SVAL(pml->buf.data,smb_mid) == mid && !pml->processed) {
 610                         return True;
 611                 }
 612         }
 613         return False;
 614 }
 615
 616 /****************************************************************************
 617  Return the message queued by this mid.
 618 ****************************************************************************/
 619
 620 struct pending_message_list *get_open_deferred_message(uint16 mid)
 621 {
 622         struct pending_message_list *pml;
 623
 624         for (pml = deferred_open_queue; pml; pml = pml->next) {
 625                 if (SVAL(pml->buf.data,smb_mid) == mid) {
 626                         return pml;
 627                 }
 628         }
 629         return NULL;
 630 }
 631
 632 /****************************************************************************
 633  Function to push a deferred open smb message onto a linked list of local smb
 634  messages ready for processing.
 635 ****************************************************************************/
 636
 637 bool push_deferred_smb_message(struct smb_request *req,
 638                                struct timeval request_time,
 639                                struct timeval timeout,
 640                                char *private_data, size_t priv_len)
 641 {
 642         struct timeval end_time;
 643
 644         if (req->unread_bytes) {
 645                 DEBUG(0,("push_deferred_smb_message: logic error ! "
 646                         "unread_bytes = %u\n",
 647                         (unsigned int)req->unread_bytes ));
 648                 smb_panic("push_deferred_smb_message: "
 649                         "logic error unread_bytes != 0" );
 650         }
 651
 652         end_time = timeval_sum(&request_time, &timeout);
 653
 654         DEBUG(10,("push_deferred_open_smb_message: pushing message len %u mid %u "
 655                   "timeout time [%u.%06u]\n",
 656                   (unsigned int) smb_len(req->inbuf)+4, (unsigned int)req->mid,
 657                   (unsigned int)end_time.tv_sec,
 658                   (unsigned int)end_time.tv_usec));
 659
 660         return push_queued_message(req, request_time, end_time,
 661                                    private_data, priv_len);
 662 }
 663
 664 struct idle_event {
 665         struct timed_event *te;
 666         struct timeval interval;
 667         char *name;
 668         bool (*handler)(const struct timeval *now, void *private_data);
 669         void *private_data;
 670 };
 671
 672 static void smbd_idle_event_handler(struct event_context *ctx,
 673                                     struct timed_event *te,
 674                                     struct timeval now,
 675                                     void *private_data)
 676 {
 677         struct idle_event *event =
 678                 talloc_get_type_abort(private_data, struct idle_event);
 679
 680         TALLOC_FREE(event->te);
 681
 682         DEBUG(10,("smbd_idle_event_handler: %s %p called\n",
 683                   event->name, event->te));
 684
 685         if (!event->handler(&now, event->private_data)) {
 686                 DEBUG(10,("smbd_idle_event_handler: %s %p stopped\n",
 687                           event->name, event->te));
 688                 /* Don't repeat, delete ourselves */
 689                 TALLOC_FREE(event);
 690                 return;
 691         }
 692
 693         DEBUG(10,("smbd_idle_event_handler: %s %p rescheduled\n",
 694                   event->name, event->te));
 695
 696         event->te = event_add_timed(ctx, event,
 697                                     timeval_sum(&now, &event->interval),
 698                                     smbd_idle_event_handler, event);
 699
 700         /* We can't do much but fail here. */
 701         SMB_ASSERT(event->te != NULL);
 702 }
 703
 704 struct idle_event *event_add_idle(struct event_context *event_ctx,
 705                                   TALLOC_CTX *mem_ctx,
 706                                   struct timeval interval,
 707                                   const char *name,
 708                                   bool (*handler)(const struct timeval *now,
 709                                                   void *private_data),
 710                                   void *private_data)
 711 {
 712         struct idle_event *result;
 713         struct timeval now = timeval_current();
 714
 715         result = TALLOC_P(mem_ctx, struct idle_event);
 716         if (result == NULL) {
 717                 DEBUG(0, ("talloc failed\n"));
 718                 return NULL;
 719         }
 720
 721         result->interval = interval;
 722         result->handler = handler;
 723         result->private_data = private_data;
 724
 725         if (!(result->name = talloc_asprintf(result, "idle_evt(%s)", name))) {
 726                 DEBUG(0, ("talloc failed\n"));
 727                 TALLOC_FREE(result);
 728                 return NULL;
 729         }
 730
 731         result->te = event_add_timed(event_ctx, result,
 732                                      timeval_sum(&now, &interval),
 733                                      smbd_idle_event_handler, result);
 734         if (result->te == NULL) {
 735                 DEBUG(0, ("event_add_timed failed\n"));
 736                 TALLOC_FREE(result);
 737                 return NULL;
 738         }
 739
 740         DEBUG(10,("event_add_idle: %s %p\n", result->name, result->te));
 741         return result;
 742 }
 743
 744 static void smbd_sig_term_handler(struct tevent_context *ev,
 745                                   struct tevent_signal *se,
 746                                   int signum,
 747                                   int count,
 748                                   void *siginfo,
 749                                   void *private_data)
 750 {
 751         exit_server_cleanly("termination signal");
 752 }
 753
 754 void smbd_setup_sig_term_handler(void)
 755 {
 756         struct tevent_signal *se;
 757
 758         se = tevent_add_signal(smbd_event_context(),
 759                                smbd_event_context(),
 760                                SIGTERM, 0,
 761                                smbd_sig_term_handler,
 762                                NULL);
 763         if (!se) {
 764                 exit_server("failed to setup SIGTERM handler");
 765         }
 766 }
 767
 768 static void smbd_sig_hup_handler(struct tevent_context *ev,
 769                                   struct tevent_signal *se,
 770                                   int signum,
 771                                   int count,
 772                                   void *siginfo,
 773                                   void *private_data)
 774 {
 775         change_to_root_user();
 776         DEBUG(1,("Reloading services after SIGHUP\n"));
 777         reload_services(False);
 778 }
 779
 780 void smbd_setup_sig_hup_handler(void)
 781 {
 782         struct tevent_signal *se;
 783
 784         se = tevent_add_signal(smbd_event_context(),
 785                                smbd_event_context(),
 786                                SIGHUP, 0,
 787                                smbd_sig_hup_handler,
 788                                NULL);
 789         if (!se) {
 790                 exit_server("failed to setup SIGHUP handler");
 791         }
 792 }
 793
 794 static NTSTATUS smbd_server_connection_loop_once(struct smbd_server_connection *conn)
 795 {
 796         fd_set r_fds, w_fds;
 797         int selrtn;
 798         struct timeval to;
 799         int maxfd = 0;
 800
 801         to.tv_sec = SMBD_SELECT_TIMEOUT;
 802         to.tv_usec = 0;
 803
 804         /*
 805          * Setup the select fd sets.
 806          */
 807
 808         FD_ZERO(&r_fds);
 809         FD_ZERO(&w_fds);
 810
 811         /*
 812          * Are there any timed events waiting ? If so, ensure we don't
 813          * select for longer than it would take to wait for them.
 814          */
 815
 816         {
 817                 struct timeval now;
 818                 GetTimeOfDay(&now);
 819
 820                 event_add_to_select_args(smbd_event_context(), &now,
 821                                          &r_fds, &w_fds, &to, &maxfd);
 822         }
 823
 824         /* Process a signal and timed events now... */
 825         if (run_events(smbd_event_context(), 0, NULL, NULL)) {
 826                 return NT_STATUS_RETRY;
 827         }
 828
 829         {
 830                 int sav;
 831                 START_PROFILE(smbd_idle);
 832
 833                 selrtn = sys_select(maxfd+1,&r_fds,&w_fds,NULL,&to);
 834                 sav = errno;
 835
 836                 END_PROFILE(smbd_idle);
 837                 errno = sav;
 838         }
 839
 840         if (run_events(smbd_event_context(), selrtn, &r_fds, &w_fds)) {
 841                 return NT_STATUS_RETRY;
 842         }
 843
 844         /* Check if error */
 845         if (selrtn == -1) {
 846                 /* something is wrong. Maybe the socket is dead? */
 847                 return map_nt_error_from_unix(errno);
 848         }
 849
 850         /* Did we timeout ? */
 851         if (selrtn == 0) {
 852                 return NT_STATUS_RETRY;
 853         }
 854
 855         /* should not be reached */
 856         return NT_STATUS_INTERNAL_ERROR;
 857 }
 858
 859 /*
 860  * Only allow 5 outstanding trans requests. We're allocating memory, so
 861  * prevent a DoS.
 862  */
 863
 864 NTSTATUS allow_new_trans(struct trans_state *list, int mid)
 865 {
 866         int count = 0;
 867         for (; list != NULL; list = list->next) {
 868
 869                 if (list->mid == mid) {
 870                         return NT_STATUS_INVALID_PARAMETER;
 871                 }
 872
 873                 count += 1;
 874         }
 875         if (count > 5) {
 876                 return NT_STATUS_INSUFFICIENT_RESOURCES;
 877         }
 878
 879         return NT_STATUS_OK;
 880 }
 881
 882 /*
 883 These flags determine some of the permissions required to do an operation
 884
 885 Note that I don't set NEED_WRITE on some write operations because they
 886 are used by some brain-dead clients when printing, and I don't want to
 887 force write permissions on print services.
 888 */
 889 #define AS_USER (1<<0)
 890 #define NEED_WRITE (1<<1) /* Must be paired with AS_USER */
 891 #define TIME_INIT (1<<2)
 892 #define CAN_IPC (1<<3) /* Must be paired with AS_USER */
 893 #define AS_GUEST (1<<5) /* Must *NOT* be paired with AS_USER */
 894 #define DO_CHDIR (1<<6)
 895
 896 /*
 897    define a list of possible SMB messages and their corresponding
 898    functions. Any message that has a NULL function is unimplemented -
 899    please feel free to contribute implementations!
 900 */
 901 static const struct smb_message_struct {
 902         const char *name;
 903         void (*fn)(struct smb_request *req);
 904         int flags;
 905 } smb_messages[256] = {
 906
 907 /* 0x00 */ { "SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE},
 908 /* 0x01 */ { "SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE},
 909 /* 0x02 */ { "SMBopen",reply_open,AS_USER },
 910 /* 0x03 */ { "SMBcreate",reply_mknew,AS_USER},
 911 /* 0x04 */ { "SMBclose",reply_close,AS_USER | CAN_IPC },
 912 /* 0x05 */ { "SMBflush",reply_flush,AS_USER},
 913 /* 0x06 */ { "SMBunlink",reply_unlink,AS_USER | NEED_WRITE },
 914 /* 0x07 */ { "SMBmv",reply_mv,AS_USER | NEED_WRITE },
 915 /* 0x08 */ { "SMBgetatr",reply_getatr,AS_USER},
 916 /* 0x09 */ { "SMBsetatr",reply_setatr,AS_USER | NEED_WRITE},
 917 /* 0x0a */ { "SMBread",reply_read,AS_USER},
 918 /* 0x0b */ { "SMBwrite",reply_write,AS_USER | CAN_IPC },
 919 /* 0x0c */ { "SMBlock",reply_lock,AS_USER},
 920 /* 0x0d */ { "SMBunlock",reply_unlock,AS_USER},
 921 /* 0x0e */ { "SMBctemp",reply_ctemp,AS_USER },
 922 /* 0x0f */ { "SMBmknew",reply_mknew,AS_USER},
 923 /* 0x10 */ { "SMBcheckpath",reply_checkpath,AS_USER},
 924 /* 0x11 */ { "SMBexit",reply_exit,DO_CHDIR},
 925 /* 0x12 */ { "SMBlseek",reply_lseek,AS_USER},
 926 /* 0x13 */ { "SMBlockread",reply_lockread,AS_USER},
 927 /* 0x14 */ { "SMBwriteunlock",reply_writeunlock,AS_USER},
 928 /* 0x15 */ { NULL, NULL, 0 },
 929 /* 0x16 */ { NULL, NULL, 0 },
 930 /* 0x17 */ { NULL, NULL, 0 },
 931 /* 0x18 */ { NULL, NULL, 0 },
 932 /* 0x19 */ { NULL, NULL, 0 },
 933 /* 0x1a */ { "SMBreadbraw",reply_readbraw,AS_USER},
 934 /* 0x1b */ { "SMBreadBmpx",reply_readbmpx,AS_USER},
 935 /* 0x1c */ { "SMBreadBs",reply_readbs,AS_USER },
 936 /* 0x1d */ { "SMBwritebraw",reply_writebraw,AS_USER},
 937 /* 0x1e */ { "SMBwriteBmpx",reply_writebmpx,AS_USER},
 938 /* 0x1f */ { "SMBwriteBs",reply_writebs,AS_USER},
 939 /* 0x20 */ { "SMBwritec", NULL,0},
 940 /* 0x21 */ { NULL, NULL, 0 },
 941 /* 0x22 */ { "SMBsetattrE",reply_setattrE,AS_USER | NEED_WRITE },
 942 /* 0x23 */ { "SMBgetattrE",reply_getattrE,AS_USER },
 943 /* 0x24 */ { "SMBlockingX",reply_lockingX,AS_USER },
 944 /* 0x25 */ { "SMBtrans",reply_trans,AS_USER | CAN_IPC },
 945 /* 0x26 */ { "SMBtranss",reply_transs,AS_USER | CAN_IPC},
 946 /* 0x27 */ { "SMBioctl",reply_ioctl,0},
 947 /* 0x28 */ { "SMBioctls", NULL,AS_USER},
 948 /* 0x29 */ { "SMBcopy",reply_copy,AS_USER | NEED_WRITE },
 949 /* 0x2a */ { "SMBmove", NULL,AS_USER | NEED_WRITE },
 950 /* 0x2b */ { "SMBecho",reply_echo,0},
 951 /* 0x2c */ { "SMBwriteclose",reply_writeclose,AS_USER},
 952 /* 0x2d */ { "SMBopenX",reply_open_and_X,AS_USER | CAN_IPC },
 953 /* 0x2e */ { "SMBreadX",reply_read_and_X,AS_USER | CAN_IPC },
 954 /* 0x2f */ { "SMBwriteX",reply_write_and_X,AS_USER | CAN_IPC },
 955 /* 0x30 */ { NULL, NULL, 0 },
 956 /* 0x31 */ { NULL, NULL, 0 },
 957 /* 0x32 */ { "SMBtrans2",reply_trans2, AS_USER | CAN_IPC },
 958 /* 0x33 */ { "SMBtranss2",reply_transs2, AS_USER | CAN_IPC },
 959 /* 0x34 */ { "SMBfindclose",reply_findclose,AS_USER},
 960 /* 0x35 */ { "SMBfindnclose",reply_findnclose,AS_USER},
 961 /* 0x36 */ { NULL, NULL, 0 },
 962 /* 0x37 */ { NULL, NULL, 0 },
 963 /* 0x38 */ { NULL, NULL, 0 },
 964 /* 0x39 */ { NULL, NULL, 0 },
 965 /* 0x3a */ { NULL, NULL, 0 },
 966 /* 0x3b */ { NULL, NULL, 0 },
 967 /* 0x3c */ { NULL, NULL, 0 },
 968 /* 0x3d */ { NULL, NULL, 0 },
 969 /* 0x3e */ { NULL, NULL, 0 },
 970 /* 0x3f */ { NULL, NULL, 0 },
 971 /* 0x40 */ { NULL, NULL, 0 },
 972 /* 0x41 */ { NULL, NULL, 0 },
 973 /* 0x42 */ { NULL, NULL, 0 },
 974 /* 0x43 */ { NULL, NULL, 0 },
 975 /* 0x44 */ { NULL, NULL, 0 },
 976 /* 0x45 */ { NULL, NULL, 0 },
 977 /* 0x46 */ { NULL, NULL, 0 },
 978 /* 0x47 */ { NULL, NULL, 0 },
 979 /* 0x48 */ { NULL, NULL, 0 },
 980 /* 0x49 */ { NULL, NULL, 0 },
 981 /* 0x4a */ { NULL, NULL, 0 },
 982 /* 0x4b */ { NULL, NULL, 0 },
 983 /* 0x4c */ { NULL, NULL, 0 },
 984 /* 0x4d */ { NULL, NULL, 0 },
 985 /* 0x4e */ { NULL, NULL, 0 },
 986 /* 0x4f */ { NULL, NULL, 0 },
 987 /* 0x50 */ { NULL, NULL, 0 },
 988 /* 0x51 */ { NULL, NULL, 0 },
 989 /* 0x52 */ { NULL, NULL, 0 },
 990 /* 0x53 */ { NULL, NULL, 0 },
 991 /* 0x54 */ { NULL, NULL, 0 },
 992 /* 0x55 */ { NULL, NULL, 0 },
 993 /* 0x56 */ { NULL, NULL, 0 },
 994 /* 0x57 */ { NULL, NULL, 0 },
 995 /* 0x58 */ { NULL, NULL, 0 },
 996 /* 0x59 */ { NULL, NULL, 0 },
 997 /* 0x5a */ { NULL, NULL, 0 },
 998 /* 0x5b */ { NULL, NULL, 0 },
 999 /* 0x5c */ { NULL, NULL, 0 },
1000 /* 0x5d */ { NULL, NULL, 0 },
1001 /* 0x5e */ { NULL, NULL, 0 },
1002 /* 0x5f */ { NULL, NULL, 0 },
1003 /* 0x60 */ { NULL, NULL, 0 },
1004 /* 0x61 */ { NULL, NULL, 0 },
1005 /* 0x62 */ { NULL, NULL, 0 },
1006 /* 0x63 */ { NULL, NULL, 0 },
1007 /* 0x64 */ { NULL, NULL, 0 },
1008 /* 0x65 */ { NULL, NULL, 0 },
1009 /* 0x66 */ { NULL, NULL, 0 },
1010 /* 0x67 */ { NULL, NULL, 0 },
1011 /* 0x68 */ { NULL, NULL, 0 },
1012 /* 0x69 */ { NULL, NULL, 0 },
1013 /* 0x6a */ { NULL, NULL, 0 },
1014 /* 0x6b */ { NULL, NULL, 0 },
1015 /* 0x6c */ { NULL, NULL, 0 },
1016 /* 0x6d */ { NULL, NULL, 0 },
1017 /* 0x6e */ { NULL, NULL, 0 },
1018 /* 0x6f */ { NULL, NULL, 0 },
1019 /* 0x70 */ { "SMBtcon",reply_tcon,0},
1020 /* 0x71 */ { "SMBtdis",reply_tdis,DO_CHDIR},
1021 /* 0x72 */ { "SMBnegprot",reply_negprot,0},
1022 /* 0x73 */ { "SMBsesssetupX",reply_sesssetup_and_X,0},
1023 /* 0x74 */ { "SMBulogoffX",reply_ulogoffX, 0}, /* ulogoff doesn't give a valid TID */
1024 /* 0x75 */ { "SMBtconX",reply_tcon_and_X,0},
1025 /* 0x76 */ { NULL, NULL, 0 },
1026 /* 0x77 */ { NULL, NULL, 0 },
1027 /* 0x78 */ { NULL, NULL, 0 },
1028 /* 0x79 */ { NULL, NULL, 0 },
1029 /* 0x7a */ { NULL, NULL, 0 },
1030 /* 0x7b */ { NULL, NULL, 0 },
1031 /* 0x7c */ { NULL, NULL, 0 },
1032 /* 0x7d */ { NULL, NULL, 0 },
1033 /* 0x7e */ { NULL, NULL, 0 },
1034 /* 0x7f */ { NULL, NULL, 0 },
1035 /* 0x80 */ { "SMBdskattr",reply_dskattr,AS_USER},
1036 /* 0x81 */ { "SMBsearch",reply_search,AS_USER},
1037 /* 0x82 */ { "SMBffirst",reply_search,AS_USER},
1038 /* 0x83 */ { "SMBfunique",reply_search,AS_USER},
1039 /* 0x84 */ { "SMBfclose",reply_fclose,AS_USER},
1040 /* 0x85 */ { NULL, NULL, 0 },
1041 /* 0x86 */ { NULL, NULL, 0 },
1042 /* 0x87 */ { NULL, NULL, 0 },
1043 /* 0x88 */ { NULL, NULL, 0 },
1044 /* 0x89 */ { NULL, NULL, 0 },
1045 /* 0x8a */ { NULL, NULL, 0 },
1046 /* 0x8b */ { NULL, NULL, 0 },
1047 /* 0x8c */ { NULL, NULL, 0 },
1048 /* 0x8d */ { NULL, NULL, 0 },
1049 /* 0x8e */ { NULL, NULL, 0 },
1050 /* 0x8f */ { NULL, NULL, 0 },
1051 /* 0x90 */ { NULL, NULL, 0 },
1052 /* 0x91 */ { NULL, NULL, 0 },
1053 /* 0x92 */ { NULL, NULL, 0 },
1054 /* 0x93 */ { NULL, NULL, 0 },
1055 /* 0x94 */ { NULL, NULL, 0 },
1056 /* 0x95 */ { NULL, NULL, 0 },
1057 /* 0x96 */ { NULL, NULL, 0 },
1058 /* 0x97 */ { NULL, NULL, 0 },
1059 /* 0x98 */ { NULL, NULL, 0 },
1060 /* 0x99 */ { NULL, NULL, 0 },
1061 /* 0x9a */ { NULL, NULL, 0 },
1062 /* 0x9b */ { NULL, NULL, 0 },
1063 /* 0x9c */ { NULL, NULL, 0 },
1064 /* 0x9d */ { NULL, NULL, 0 },
1065 /* 0x9e */ { NULL, NULL, 0 },
1066 /* 0x9f */ { NULL, NULL, 0 },
1067 /* 0xa0 */ { "SMBnttrans",reply_nttrans, AS_USER | CAN_IPC },
1068 /* 0xa1 */ { "SMBnttranss",reply_nttranss, AS_USER | CAN_IPC },
1069 /* 0xa2 */ { "SMBntcreateX",reply_ntcreate_and_X, AS_USER | CAN_IPC },
1070 /* 0xa3 */ { NULL, NULL, 0 },
1071 /* 0xa4 */ { "SMBntcancel",reply_ntcancel, 0 },
1072 /* 0xa5 */ { "SMBntrename",reply_ntrename, AS_USER | NEED_WRITE },
1073 /* 0xa6 */ { NULL, NULL, 0 },
1074 /* 0xa7 */ { NULL, NULL, 0 },
1075 /* 0xa8 */ { NULL, NULL, 0 },
1076 /* 0xa9 */ { NULL, NULL, 0 },
1077 /* 0xaa */ { NULL, NULL, 0 },
1078 /* 0xab */ { NULL, NULL, 0 },
1079 /* 0xac */ { NULL, NULL, 0 },
1080 /* 0xad */ { NULL, NULL, 0 },
1081 /* 0xae */ { NULL, NULL, 0 },
1082 /* 0xaf */ { NULL, NULL, 0 },
1083 /* 0xb0 */ { NULL, NULL, 0 },
1084 /* 0xb1 */ { NULL, NULL, 0 },
1085 /* 0xb2 */ { NULL, NULL, 0 },
1086 /* 0xb3 */ { NULL, NULL, 0 },
1087 /* 0xb4 */ { NULL, NULL, 0 },
1088 /* 0xb5 */ { NULL, NULL, 0 },
1089 /* 0xb6 */ { NULL, NULL, 0 },
1090 /* 0xb7 */ { NULL, NULL, 0 },
1091 /* 0xb8 */ { NULL, NULL, 0 },
1092 /* 0xb9 */ { NULL, NULL, 0 },
1093 /* 0xba */ { NULL, NULL, 0 },
1094 /* 0xbb */ { NULL, NULL, 0 },
1095 /* 0xbc */ { NULL, NULL, 0 },
1096 /* 0xbd */ { NULL, NULL, 0 },
1097 /* 0xbe */ { NULL, NULL, 0 },
1098 /* 0xbf */ { NULL, NULL, 0 },
1099 /* 0xc0 */ { "SMBsplopen",reply_printopen,AS_USER},
1100 /* 0xc1 */ { "SMBsplwr",reply_printwrite,AS_USER},
1101 /* 0xc2 */ { "SMBsplclose",reply_printclose,AS_USER},
1102 /* 0xc3 */ { "SMBsplretq",reply_printqueue,AS_USER},
1103 /* 0xc4 */ { NULL, NULL, 0 },
1104 /* 0xc5 */ { NULL, NULL, 0 },
1105 /* 0xc6 */ { NULL, NULL, 0 },
1106 /* 0xc7 */ { NULL, NULL, 0 },
1107 /* 0xc8 */ { NULL, NULL, 0 },
1108 /* 0xc9 */ { NULL, NULL, 0 },
1109 /* 0xca */ { NULL, NULL, 0 },
1110 /* 0xcb */ { NULL, NULL, 0 },
1111 /* 0xcc */ { NULL, NULL, 0 },
1112 /* 0xcd */ { NULL, NULL, 0 },
1113 /* 0xce */ { NULL, NULL, 0 },
1114 /* 0xcf */ { NULL, NULL, 0 },
1115 /* 0xd0 */ { "SMBsends",reply_sends,AS_GUEST},
1116 /* 0xd1 */ { "SMBsendb", NULL,AS_GUEST},
1117 /* 0xd2 */ { "SMBfwdname", NULL,AS_GUEST},
1118 /* 0xd3 */ { "SMBcancelf", NULL,AS_GUEST},
1119 /* 0xd4 */ { "SMBgetmac", NULL,AS_GUEST},
1120 /* 0xd5 */ { "SMBsendstrt",reply_sendstrt,AS_GUEST},
1121 /* 0xd6 */ { "SMBsendend",reply_sendend,AS_GUEST},
1122 /* 0xd7 */ { "SMBsendtxt",reply_sendtxt,AS_GUEST},
1123 /* 0xd8 */ { NULL, NULL, 0 },
1124 /* 0xd9 */ { NULL, NULL, 0 },
1125 /* 0xda */ { NULL, NULL, 0 },
1126 /* 0xdb */ { NULL, NULL, 0 },
1127 /* 0xdc */ { NULL, NULL, 0 },
1128 /* 0xdd */ { NULL, NULL, 0 },
1129 /* 0xde */ { NULL, NULL, 0 },
1130 /* 0xdf */ { NULL, NULL, 0 },
1131 /* 0xe0 */ { NULL, NULL, 0 },
1132 /* 0xe1 */ { NULL, NULL, 0 },
1133 /* 0xe2 */ { NULL, NULL, 0 },
1134 /* 0xe3 */ { NULL, NULL, 0 },
1135 /* 0xe4 */ { NULL, NULL, 0 },
1136 /* 0xe5 */ { NULL, NULL, 0 },
1137 /* 0xe6 */ { NULL, NULL, 0 },
1138 /* 0xe7 */ { NULL, NULL, 0 },
1139 /* 0xe8 */ { NULL, NULL, 0 },
1140 /* 0xe9 */ { NULL, NULL, 0 },
1141 /* 0xea */ { NULL, NULL, 0 },
1142 /* 0xeb */ { NULL, NULL, 0 },
1143 /* 0xec */ { NULL, NULL, 0 },
1144 /* 0xed */ { NULL, NULL, 0 },
1145 /* 0xee */ { NULL, NULL, 0 },
1146 /* 0xef */ { NULL, NULL, 0 },
1147 /* 0xf0 */ { NULL, NULL, 0 },
1148 /* 0xf1 */ { NULL, NULL, 0 },
1149 /* 0xf2 */ { NULL, NULL, 0 },
1150 /* 0xf3 */ { NULL, NULL, 0 },
1151 /* 0xf4 */ { NULL, NULL, 0 },
1152 /* 0xf5 */ { NULL, NULL, 0 },
1153 /* 0xf6 */ { NULL, NULL, 0 },
1154 /* 0xf7 */ { NULL, NULL, 0 },
1155 /* 0xf8 */ { NULL, NULL, 0 },
1156 /* 0xf9 */ { NULL, NULL, 0 },
1157 /* 0xfa */ { NULL, NULL, 0 },
1158 /* 0xfb */ { NULL, NULL, 0 },
1159 /* 0xfc */ { NULL, NULL, 0 },
1160 /* 0xfd */ { NULL, NULL, 0 },
1161 /* 0xfe */ { NULL, NULL, 0 },
1162 /* 0xff */ { NULL, NULL, 0 }
1163
1164 };
1165
1166 /*******************************************************************
1167  allocate and initialize a reply packet
1168 ********************************************************************/
1169
1170 static bool create_outbuf(TALLOC_CTX *mem_ctx, struct smb_request *req,
1171                           const char *inbuf, char **outbuf, uint8_t num_words,
1172                           uint32_t num_bytes)
1173 {
1174         /*
1175          * Protect against integer wrap
1176          */
1177         if ((num_bytes > 0xffffff)
1178             || ((num_bytes + smb_size + num_words*2) > 0xffffff)) {
1179                 char *msg;
1180                 if (asprintf(&msg, "num_bytes too large: %u",
1181                              (unsigned)num_bytes) == -1) {
1182                         msg = CONST_DISCARD(char *, "num_bytes too large");
1183                 }
1184                 smb_panic(msg);
1185         }
1186
1187         *outbuf = TALLOC_ARRAY(mem_ctx, char,
1188                                smb_size + num_words*2 + num_bytes);
1189         if (*outbuf == NULL) {
1190                 return false;
1191         }
1192
1193         construct_reply_common(req, inbuf, *outbuf);
1194         srv_set_message(*outbuf, num_words, num_bytes, false);
1195         /*
1196          * Zero out the word area, the caller has to take care of the bcc area
1197          * himself
1198          */
1199         if (num_words != 0) {
1200                 memset(*outbuf + smb_vwv0, 0, num_words*2);
1201         }
1202
1203         return true;
1204 }
1205
1206 void reply_outbuf(struct smb_request *req, uint8 num_words, uint32 num_bytes)
1207 {
1208         char *outbuf;
1209         if (!create_outbuf(req, req, (char *)req->inbuf, &outbuf, num_words,
1210                            num_bytes)) {
1211                 smb_panic("could not allocate output buffer\n");
1212         }
1213         req->outbuf = (uint8_t *)outbuf;
1214 }
1215
1216
1217 /*******************************************************************
1218  Dump a packet to a file.
1219 ********************************************************************/
1220
1221 static void smb_dump(const char *name, int type, const char *data, ssize_t len)
1222 {
1223         int fd, i;
1224         char *fname = NULL;
1225         if (DEBUGLEVEL < 50) {
1226                 return;
1227         }
1228
1229         if (len < 4) len = smb_len(data)+4;
1230         for (i=1;i<100;i++) {
1231                 if (asprintf(&fname, "/tmp/%s.%d.%s", name, i,
1232                              type ? "req" : "resp") == -1) {
1233                         return;
1234                 }
1235                 fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0644);
1236                 if (fd != -1 || errno != EEXIST) break;
1237         }
1238         if (fd != -1) {
1239                 ssize_t ret = write(fd, data, len);
1240                 if (ret != len)
1241                         DEBUG(0,("smb_dump: problem: write returned %d\n", (int)ret ));
1242                 close(fd);
1243                 DEBUG(0,("created %s len %lu\n", fname, (unsigned long)len));
1244         }
1245         SAFE_FREE(fname);
1246 }
1247
1248 /****************************************************************************
1249  Prepare everything for calling the actual request function, and potentially
1250  call the request function via the "new" interface.
1251
1252  Return False if the "legacy" function needs to be called, everything is
1253  prepared.
1254
1255  Return True if we're done.
1256
1257  I know this API sucks, but it is the one with the least code change I could
1258  find.
1259 ****************************************************************************/
1260
1261 static connection_struct *switch_message(uint8 type, struct smb_request *req, int size)
1262 {
1263         int flags;
1264         uint16 session_tag;
1265         connection_struct *conn = NULL;
1266         struct smbd_server_connection *sconn = smbd_server_conn;
1267
1268         errno = 0;
1269
1270         /* Make sure this is an SMB packet. smb_size contains NetBIOS header
1271          * so subtract 4 from it. */
1272         if (!valid_smb_header(req->inbuf)
1273             || (size < (smb_size - 4))) {
1274                 DEBUG(2,("Non-SMB packet of length %d. Terminating server\n",
1275                          smb_len(req->inbuf)));
1276                 exit_server_cleanly("Non-SMB packet");
1277         }
1278
1279         if (smb_messages[type].fn == NULL) {
1280                 DEBUG(0,("Unknown message type %d!\n",type));
1281                 smb_dump("Unknown", 1, (char *)req->inbuf, size);
1282                 reply_unknown_new(req, type);
1283                 return NULL;
1284         }
1285
1286         flags = smb_messages[type].flags;
1287
1288         /* In share mode security we must ignore the vuid. */
1289         session_tag = (lp_security() == SEC_SHARE)
1290                 ? UID_FIELD_INVALID : req->vuid;
1291         conn = req->conn;
1292
1293         DEBUG(3,("switch message %s (pid %d) conn 0x%lx\n", smb_fn_name(type),
1294                  (int)sys_getpid(), (unsigned long)conn));
1295
1296         smb_dump(smb_fn_name(type), 1, (char *)req->inbuf, size);
1297
1298         /* Ensure this value is replaced in the incoming packet. */
1299         SSVAL(req->inbuf,smb_uid,session_tag);
1300
1301         /*
1302          * Ensure the correct username is in current_user_info.  This is a
1303          * really ugly bugfix for problems with multiple session_setup_and_X's
1304          * being done and allowing %U and %G substitutions to work correctly.
1305          * There is a reason this code is done here, don't move it unless you
1306          * know what you're doing... :-).
1307          * JRA.
1308          */
1309
1310         if (session_tag != sconn->smb1.sessions.last_session_tag) {
1311                 user_struct *vuser = NULL;
1312
1313                 sconn->smb1.sessions.last_session_tag = session_tag;
1314                 if(session_tag != UID_FIELD_INVALID) {
1315                         vuser = get_valid_user_struct(sconn, session_tag);
1316                         if (vuser) {
1317                                 set_current_user_info(
1318                                         vuser->server_info->sanitized_username,
1319                                         vuser->server_info->unix_name,
1320                                         pdb_get_domain(vuser->server_info
1321                                                        ->sam_account));
1322                         }
1323                 }
1324         }
1325
1326         /* Does this call need to be run as the connected user? */
1327         if (flags & AS_USER) {
1328
1329                 /* Does this call need a valid tree connection? */
1330                 if (!conn) {
1331                         /*
1332                          * Amazingly, the error code depends on the command
1333                          * (from Samba4).
1334                          */
1335                         if (type == SMBntcreateX) {
1336                                 reply_nterror(req, NT_STATUS_INVALID_HANDLE);
1337                         } else {
1338                                 reply_nterror(req, NT_STATUS_NETWORK_NAME_DELETED);
1339                         }
1340                         return NULL;
1341                 }
1342
1343                 if (!change_to_user(conn,session_tag)) {
1344                         DEBUG(0, ("Error: Could not change to user. Removing "
1345                             "deferred open, mid=%d.\n", req->mid));
1346                         reply_nterror(req, NT_STATUS_DOS(ERRSRV, ERRbaduid));
1347                         return conn;
1348                 }
1349
1350                 /* All NEED_WRITE and CAN_IPC flags must also have AS_USER. */
1351
1352                 /* Does it need write permission? */
1353                 if ((flags & NEED_WRITE) && !CAN_WRITE(conn)) {
1354                         reply_nterror(req, NT_STATUS_MEDIA_WRITE_PROTECTED);
1355                         return conn;
1356                 }
1357
1358                 /* IPC services are limited */
1359                 if (IS_IPC(conn) && !(flags & CAN_IPC)) {
1360                         reply_nterror(req, NT_STATUS_ACCESS_DENIED);
1361                         return conn;
1362                 }
1363         } else {
1364                 /* This call needs to be run as root */
1365                 change_to_root_user();
1366         }
1367
1368         /* load service specific parameters */
1369         if (conn) {
1370                 if (req->encrypted) {
1371                         conn->encrypted_tid = true;
1372                         /* encrypted required from now on. */
1373                         conn->encrypt_level = Required;
1374                 } else if (ENCRYPTION_REQUIRED(conn)) {
1375                         if (req->cmd != SMBtrans2 && req->cmd != SMBtranss2) {
1376                                 exit_server_cleanly("encryption required "
1377                                         "on connection");
1378                                 return conn;
1379                         }
1380                 }
1381
1382                 if (!set_current_service(conn,SVAL(req->inbuf,smb_flg),
1383                                          (flags & (AS_USER|DO_CHDIR)
1384                                           ?True:False))) {
1385                         reply_nterror(req, NT_STATUS_ACCESS_DENIED);
1386                         return conn;
1387                 }
1388                 conn->num_smb_operations++;
1389         }
1390
1391         /* does this protocol need to be run as guest? */
1392         if ((flags & AS_GUEST)
1393             && (!change_to_guest() ||
1394                 !check_access(smbd_server_fd(), lp_hostsallow(-1),
1395                               lp_hostsdeny(-1)))) {
1396                 reply_nterror(req, NT_STATUS_ACCESS_DENIED);
1397                 return conn;
1398         }
1399
1400         smb_messages[type].fn(req);
1401         return req->conn;
1402 }
1403
1404 /****************************************************************************
1405  Construct a reply to the incoming packet.
1406 ****************************************************************************/
1407
1408 static void construct_reply(char *inbuf, int size, size_t unread_bytes,
1409                             uint32_t seqnum, bool encrypted,
1410                             struct smb_perfcount_data *deferred_pcd)
1411 {
1412         connection_struct *conn;
1413         struct smb_request *req;
1414
1415         if (!(req = talloc(talloc_tos(), struct smb_request))) {
1416                 smb_panic("could not allocate smb_request");
1417         }
1418
1419         init_smb_request(req, (uint8 *)inbuf, unread_bytes, encrypted);
1420         req->inbuf  = (uint8_t *)talloc_move(req, &inbuf);
1421         req->seqnum = seqnum;
1422
1423         /* we popped this message off the queue - keep original perf data */
1424         if (deferred_pcd)
1425                 req->pcd = *deferred_pcd;
1426         else {
1427                 SMB_PERFCOUNT_START(&req->pcd);
1428                 SMB_PERFCOUNT_SET_OP(&req->pcd, req->cmd);
1429                 SMB_PERFCOUNT_SET_MSGLEN_IN(&req->pcd, size);
1430         }
1431
1432         conn = switch_message(req->cmd, req, size);
1433
1434         if (req->unread_bytes) {
1435                 /* writeX failed. drain socket. */
1436                 if (drain_socket(smbd_server_fd(), req->unread_bytes) !=
1437                                 req->unread_bytes) {
1438                         smb_panic("failed to drain pending bytes");
1439                 }
1440                 req->unread_bytes = 0;
1441         }
1442
1443         if (req->done) {
1444                 TALLOC_FREE(req);
1445                 return;
1446         }
1447
1448         if (req->outbuf == NULL) {
1449                 return;
1450         }
1451
1452         if (CVAL(req->outbuf,0) == 0) {
1453                 show_msg((char *)req->outbuf);
1454         }
1455
1456         if (!srv_send_smb(smbd_server_fd(),
1457                         (char *)req->outbuf,
1458                         true, req->seqnum+1,
1459                         IS_CONN_ENCRYPTED(conn)||req->encrypted,
1460                         &req->pcd)) {
1461                 exit_server_cleanly("construct_reply: srv_send_smb failed.");
1462         }
1463
1464         TALLOC_FREE(req);
1465
1466         return;
1467 }
1468
1469 /****************************************************************************
1470  Process an smb from the client
1471 ****************************************************************************/
1472 static void process_smb(struct smbd_server_connection *conn,
1473                         uint8_t *inbuf, size_t nread, size_t unread_bytes,
1474                         uint32_t seqnum, bool encrypted,
1475                         struct smb_perfcount_data *deferred_pcd)
1476 {
1477         int msg_type = CVAL(inbuf,0);
1478
1479         DO_PROFILE_INC(smb_count);
1480
1481         DEBUG( 6, ( "got message type 0x%x of len 0x%x\n", msg_type,
1482                     smb_len(inbuf) ) );
1483         DEBUG( 3, ( "Transaction %d of length %d (%u toread)\n", trans_num,
1484                                 (int)nread,
1485                                 (unsigned int)unread_bytes ));
1486
1487         if (msg_type != 0) {
1488                 /*
1489                  * NetBIOS session request, keepalive, etc.
1490                  */
1491                 reply_special((char *)inbuf);
1492                 goto done;
1493         }
1494
1495         if (smbd_server_conn->allow_smb2) {
1496                 if (smbd_is_smb2_header(inbuf, nread)) {
1497                         smbd_smb2_first_negprot(smbd_server_conn, inbuf, nread);
1498                         return;
1499                 }
1500                 smbd_server_conn->allow_smb2 = false;
1501         }
1502
1503         show_msg((char *)inbuf);
1504
1505         construct_reply((char *)inbuf,nread,unread_bytes,seqnum,encrypted,deferred_pcd);
1506         trans_num++;
1507
1508 done:
1509         conn->smb1.num_requests++;
1510
1511         /* The timeout_processing function isn't run nearly
1512            often enough to implement 'max log size' without
1513            overrunning the size of the file by many megabytes.
1514            This is especially true if we are running at debug
1515            level 10.  Checking every 50 SMBs is a nice
1516            tradeoff of performance vs log file size overrun. */
1517
1518         if ((conn->smb1.num_requests % 50) == 0 &&
1519             need_to_check_log_size()) {
1520                 change_to_root_user();
1521                 check_log_size();
1522         }
1523 }
1524
1525 /****************************************************************************
1526  Return a string containing the function name of a SMB command.
1527 ****************************************************************************/
1528
1529 const char *smb_fn_name(int type)
1530 {
1531         const char *unknown_name = "SMBunknown";
1532
1533         if (smb_messages[type].name == NULL)
1534                 return(unknown_name);
1535
1536         return(smb_messages[type].name);
1537 }
1538
1539 /****************************************************************************
1540  Helper functions for contruct_reply.
1541 ****************************************************************************/
1542
1543 void add_to_common_flags2(uint32 v)
1544 {
1545         common_flags2 |= v;
1546 }
1547
1548 void remove_from_common_flags2(uint32 v)
1549 {
1550         common_flags2 &= ~v;
1551 }
1552
1553 static void construct_reply_common(struct smb_request *req, const char *inbuf,
1554                                    char *outbuf)
1555 {
1556         srv_set_message(outbuf,0,0,false);
1557
1558         SCVAL(outbuf, smb_com, req->cmd);
1559         SIVAL(outbuf,smb_rcls,0);
1560         SCVAL(outbuf,smb_flg, FLAG_REPLY | (CVAL(inbuf,smb_flg) & FLAG_CASELESS_PATHNAMES));
1561         SSVAL(outbuf,smb_flg2,
1562                 (SVAL(inbuf,smb_flg2) & FLAGS2_UNICODE_STRINGS) |
1563                 common_flags2);
1564         memset(outbuf+smb_pidhigh,'\0',(smb_tid-smb_pidhigh));
1565
1566         SSVAL(outbuf,smb_tid,SVAL(inbuf,smb_tid));
1567         SSVAL(outbuf,smb_pid,SVAL(inbuf,smb_pid));
1568         SSVAL(outbuf,smb_uid,SVAL(inbuf,smb_uid));
1569         SSVAL(outbuf,smb_mid,SVAL(inbuf,smb_mid));
1570 }
1571
1572 void construct_reply_common_req(struct smb_request *req, char *outbuf)
1573 {
1574         construct_reply_common(req, (char *)req->inbuf, outbuf);
1575 }
1576
1577 /*
1578  * How many bytes have we already accumulated up to the current wct field
1579  * offset?
1580  */
1581
1582 size_t req_wct_ofs(struct smb_request *req)
1583 {
1584         size_t buf_size;
1585
1586         if (req->chain_outbuf == NULL) {
1587                 return smb_wct - 4;
1588         }
1589         buf_size = talloc_get_size(req->chain_outbuf);
1590         if ((buf_size % 4) != 0) {
1591                 buf_size += (4 - (buf_size % 4));
1592         }
1593         return buf_size - 4;
1594 }
1595
1596 /*
1597  * Hack around reply_nterror & friends not being aware of chained requests,
1598  * generating illegal (i.e. wct==0) chain replies.
1599  */
1600
1601 static void fixup_chain_error_packet(struct smb_request *req)
1602 {
1603         uint8_t *outbuf = req->outbuf;
1604         req->outbuf = NULL;
1605         reply_outbuf(req, 2, 0);
1606         memcpy(req->outbuf, outbuf, smb_wct);
1607         TALLOC_FREE(outbuf);
1608         SCVAL(req->outbuf, smb_vwv0, 0xff);
1609 }
1610
1611 /****************************************************************************
1612  Construct a chained reply and add it to the already made reply
1613 ****************************************************************************/
1614
1615 void chain_reply(struct smb_request *req)
1616 {
1617         size_t smblen = smb_len(req->inbuf);
1618         size_t already_used, length_needed;
1619         uint8_t chain_cmd;
1620         uint32_t chain_offset;  /* uint32_t to avoid overflow */
1621
1622         uint8_t wct;
1623         uint16_t *vwv;
1624         uint16_t buflen;
1625         uint8_t *buf;
1626
1627         if (IVAL(req->outbuf, smb_rcls) != 0) {
1628                 fixup_chain_error_packet(req);
1629         }
1630
1631         /*
1632          * Any of the AndX requests and replies have at least a wct of
1633          * 2. vwv[0] is the next command, vwv[1] is the offset from the
1634          * beginning of the SMB header to the next wct field.
1635          *
1636          * None of the AndX requests put anything valuable in vwv[0] and [1],
1637          * so we can overwrite it here to form the chain.
1638          */
1639
1640         if ((req->wct < 2) || (CVAL(req->outbuf, smb_wct) < 2)) {
1641                 goto error;
1642         }
1643
1644         /*
1645          * Here we assume that this is the end of the chain. For that we need
1646          * to set "next command" to 0xff and the offset to 0. If we later find
1647          * more commands in the chain, this will be overwritten again.
1648          */
1649
1650         SCVAL(req->outbuf, smb_vwv0, 0xff);
1651         SCVAL(req->outbuf, smb_vwv0+1, 0);
1652         SSVAL(req->outbuf, smb_vwv1, 0);
1653
1654         if (req->chain_outbuf == NULL) {
1655                 /*
1656                  * In req->chain_outbuf we collect all the replies. Start the
1657                  * chain by copying in the first reply.
1658                  *
1659                  * We do the realloc because later on we depend on
1660                  * talloc_get_size to determine the length of
1661                  * chain_outbuf. The reply_xxx routines might have
1662                  * over-allocated (reply_pipe_read_and_X used to be such an
1663                  * example).
1664                  */
1665                 req->chain_outbuf = TALLOC_REALLOC_ARRAY(
1666                         req, req->outbuf, uint8_t, smb_len(req->outbuf) + 4);
1667                 if (req->chain_outbuf == NULL) {
1668                         goto error;
1669                 }
1670                 req->outbuf = NULL;
1671         } else {
1672                 /*
1673                  * Update smb headers where subsequent chained commands
1674                  * may have updated them.
1675                  */
1676                 SCVAL(req->chain_outbuf, smb_tid, CVAL(req->outbuf, smb_tid));
1677                 SCVAL(req->chain_outbuf, smb_uid, CVAL(req->outbuf, smb_uid));
1678
1679                 if (!smb_splice_chain(&req->chain_outbuf,
1680                                       CVAL(req->outbuf, smb_com),
1681                                       CVAL(req->outbuf, smb_wct),
1682                                       (uint16_t *)(req->outbuf + smb_vwv),
1683                                       0, smb_buflen(req->outbuf),
1684                                       (uint8_t *)smb_buf(req->outbuf))) {
1685                         goto error;
1686                 }
1687                 TALLOC_FREE(req->outbuf);
1688         }
1689
1690         /*
1691          * We use the old request's vwv field to grab the next chained command
1692          * and offset into the chained fields.
1693          */
1694
1695         chain_cmd = CVAL(req->vwv+0, 0);
1696         chain_offset = SVAL(req->vwv+1, 0);
1697
1698         if (chain_cmd == 0xff) {
1699                 /*
1700                  * End of chain, no more requests from the client. So ship the
1701                  * replies.
1702                  */
1703                 smb_setlen((char *)(req->chain_outbuf),
1704                            talloc_get_size(req->chain_outbuf) - 4);
1705
1706                 if (!srv_send_smb(smbd_server_fd(), (char *)req->chain_outbuf,
1707                                   true, req->seqnum+1,
1708                                   IS_CONN_ENCRYPTED(req->conn)
1709                                   ||req->encrypted,
1710                                   &req->pcd)) {
1711                         exit_server_cleanly("chain_reply: srv_send_smb "
1712                                             "failed.");
1713                 }
1714                 TALLOC_FREE(req->chain_outbuf);
1715                 req->done = true;
1716                 return;
1717         }
1718
1719         /* add a new perfcounter for this element of chain */
1720         SMB_PERFCOUNT_ADD(&req->pcd);
1721         SMB_PERFCOUNT_SET_OP(&req->pcd, chain_cmd);
1722         SMB_PERFCOUNT_SET_MSGLEN_IN(&req->pcd, smblen);
1723
1724         /*
1725          * Check if the client tries to fool us. The request so far uses the
1726          * space to the end of the byte buffer in the request just
1727          * processed. The chain_offset can't point into that area. If that was
1728          * the case, we could end up with an endless processing of the chain,
1729          * we would always handle the same request.
1730          */
1731
1732         already_used = PTR_DIFF(req->buf+req->buflen, smb_base(req->inbuf));
1733         if (chain_offset < already_used) {
1734                 goto error;
1735         }
1736
1737         /*
1738          * Next check: Make sure the chain offset does not point beyond the
1739          * overall smb request length.
1740          */
1741
1742         length_needed = chain_offset+1; /* wct */
1743         if (length_needed > smblen) {
1744                 goto error;
1745         }
1746
1747         /*
1748          * Now comes the pointer magic. Goal here is to set up req->vwv and
1749          * req->buf correctly again to be able to call the subsequent
1750          * switch_message(). The chain offset (the former vwv[1]) points at
1751          * the new wct field.
1752          */
1753
1754         wct = CVAL(smb_base(req->inbuf), chain_offset);
1755
1756         /*
1757          * Next consistency check: Make the new vwv array fits in the overall
1758          * smb request.
1759          */
1760
1761         length_needed += (wct+1)*sizeof(uint16_t); /* vwv+buflen */
1762         if (length_needed > smblen) {
1763                 goto error;
1764         }
1765         vwv = (uint16_t *)(smb_base(req->inbuf) + chain_offset + 1);
1766
1767         /*
1768          * Now grab the new byte buffer....
1769          */
1770
1771         buflen = SVAL(vwv+wct, 0);
1772
1773         /*
1774          * .. and check that it fits.
1775          */
1776
1777         length_needed += buflen;
1778         if (length_needed > smblen) {
1779                 goto error;
1780         }
1781         buf = (uint8_t *)(vwv+wct+1);
1782
1783         req->cmd = chain_cmd;
1784         req->wct = wct;
1785         req->vwv = vwv;
1786         req->buflen = buflen;
1787         req->buf = buf;
1788
1789         switch_message(chain_cmd, req, smblen);
1790
1791         if (req->outbuf == NULL) {
1792                 /*
1793                  * This happens if the chained command has suspended itself or
1794                  * if it has called srv_send_smb() itself.
1795                  */
1796                 return;
1797         }
1798
1799         /*
1800          * We end up here if the chained command was not itself chained or
1801          * suspended, but for example a close() command. We now need to splice
1802          * the chained commands' outbuf into the already built up chain_outbuf
1803          * and ship the result.
1804          */
1805         goto done;
1806
1807  error:
1808         /*
1809          * We end up here if there's any error in the chain syntax. Report a
1810          * DOS error, just like Windows does.
1811          */
1812         reply_nterror(req, NT_STATUS_DOS(ERRSRV, ERRerror));
1813         fixup_chain_error_packet(req);
1814
1815  done:
1816         /*
1817          * This scary statement intends to set the
1818          * FLAGS2_32_BIT_ERROR_CODES flg2 field in req->chain_outbuf
1819          * to the value req->outbuf carries
1820          */
1821         SSVAL(req->chain_outbuf, smb_flg2,
1822               (SVAL(req->chain_outbuf, smb_flg2) & ~FLAGS2_32_BIT_ERROR_CODES)
1823               | (SVAL(req->outbuf, smb_flg2) & FLAGS2_32_BIT_ERROR_CODES));
1824
1825         /*
1826          * Transfer the error codes from the subrequest to the main one
1827          */
1828         SSVAL(req->chain_outbuf, smb_rcls, SVAL(req->outbuf, smb_rcls));
1829         SSVAL(req->chain_outbuf, smb_err, SVAL(req->outbuf, smb_err));
1830
1831         if (!smb_splice_chain(&req->chain_outbuf,
1832                               CVAL(req->outbuf, smb_com),
1833                               CVAL(req->outbuf, smb_wct),
1834                               (uint16_t *)(req->outbuf + smb_vwv),
1835                               0, smb_buflen(req->outbuf),
1836                               (uint8_t *)smb_buf(req->outbuf))) {
1837                 exit_server_cleanly("chain_reply: smb_splice_chain failed\n");
1838         }
1839         TALLOC_FREE(req->outbuf);
1840
1841         smb_setlen((char *)(req->chain_outbuf),
1842                    talloc_get_size(req->chain_outbuf) - 4);
1843
1844         show_msg((char *)(req->chain_outbuf));
1845
1846         if (!srv_send_smb(smbd_server_fd(), (char *)req->chain_outbuf,
1847                           true, req->seqnum+1,
1848                           IS_CONN_ENCRYPTED(req->conn)||req->encrypted,
1849                           &req->pcd)) {
1850                 exit_server_cleanly("construct_reply: srv_send_smb failed.");
1851         }
1852         TALLOC_FREE(req->chain_outbuf);
1853         req->done = true;
1854 }
1855
1856 /****************************************************************************
1857  Check if services need reloading.
1858 ****************************************************************************/
1859
1860 void check_reload(time_t t)
1861 {
1862         time_t printcap_cache_time = (time_t)lp_printcap_cache_time();
1863
1864         if(last_smb_conf_reload_time == 0) {
1865                 last_smb_conf_reload_time = t;
1866                 /* Our printing subsystem might not be ready at smbd start up.
1867                    Then no printer is available till the first printers check
1868                    is performed.  A lower initial interval circumvents this. */
1869                 if ( printcap_cache_time > 60 )
1870                         last_printer_reload_time = t - printcap_cache_time + 60;
1871                 else
1872                         last_printer_reload_time = t;
1873         }
1874
1875         if (mypid != getpid()) { /* First time or fork happened meanwhile */
1876                 /* randomize over 60 second the printcap reload to avoid all
1877                  * process hitting cupsd at the same time */
1878                 int time_range = 60;
1879
1880                 last_printer_reload_time += random() % time_range;
1881                 mypid = getpid();
1882         }
1883
1884         if (t >= last_smb_conf_reload_time+SMBD_RELOAD_CHECK) {
1885                 reload_services(True);
1886                 last_smb_conf_reload_time = t;
1887         }
1888
1889         /* 'printcap cache time = 0' disable the feature */
1890
1891         if ( printcap_cache_time != 0 )
1892         {
1893                 /* see if it's time to reload or if the clock has been set back */
1894
1895                 if ( (t >= last_printer_reload_time+printcap_cache_time)
1896                         || (t-last_printer_reload_time  < 0) )
1897                 {
1898                         DEBUG( 3,( "Printcap cache time expired.\n"));
1899                         reload_printers();
1900                         last_printer_reload_time = t;
1901                 }
1902         }
1903 }
1904
1905 static void smbd_server_connection_write_handler(struct smbd_server_connection *conn)
1906 {
1907         /* TODO: make write nonblocking */
1908 }
1909
1910 static void smbd_server_connection_read_handler(struct smbd_server_connection *conn)
1911 {
1912         uint8_t *inbuf = NULL;
1913         size_t inbuf_len = 0;
1914         size_t unread_bytes = 0;
1915         bool encrypted = false;
1916         TALLOC_CTX *mem_ctx = talloc_tos();
1917         NTSTATUS status;
1918         uint32_t seqnum;
1919
1920         /* TODO: make this completely nonblocking */
1921
1922         status = receive_smb_talloc(mem_ctx, smbd_server_fd(),
1923                                     (char **)(void *)&inbuf,
1924                                     0, /* timeout */
1925                                     &unread_bytes,
1926                                     &encrypted,
1927                                     &inbuf_len, &seqnum);
1928         if (NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
1929                 goto process;
1930         }
1931         if (NT_STATUS_IS_ERR(status)) {
1932                 exit_server_cleanly("failed to receive smb request");
1933         }
1934         if (!NT_STATUS_IS_OK(status)) {
1935                 return;
1936         }
1937
1938 process:
1939         process_smb(conn, inbuf, inbuf_len, unread_bytes,
1940                     seqnum, encrypted, NULL);
1941 }
1942
1943 static void smbd_server_connection_handler(struct event_context *ev,
1944                                            struct fd_event *fde,
1945                                            uint16_t flags,
1946                                            void *private_data)
1947 {
1948         struct smbd_server_connection *conn = talloc_get_type(private_data,
1949                                               struct smbd_server_connection);
1950
1951         if (flags & EVENT_FD_WRITE) {
1952                 smbd_server_connection_write_handler(conn);
1953         } else if (flags & EVENT_FD_READ) {
1954                 smbd_server_connection_read_handler(conn);
1955         }
1956 }
1957
1958
1959 /****************************************************************************
1960 received when we should release a specific IP
1961 ****************************************************************************/
1962 static void release_ip(const char *ip, void *priv)
1963 {
1964         char addr[INET6_ADDRSTRLEN];
1965         char *p = addr;
1966
1967         client_socket_addr(get_client_fd(),addr,sizeof(addr));
1968
1969         if (strncmp("::ffff:", addr, 7) == 0) {
1970                 p = addr + 7;
1971         }
1972
1973         if ((strcmp(p, ip) == 0) || ((p != addr) && strcmp(addr, ip) == 0)) {
1974                 /* we can't afford to do a clean exit - that involves
1975                    database writes, which would potentially mean we
1976                    are still running after the failover has finished -
1977                    we have to get rid of this process ID straight
1978                    away */
1979                 DEBUG(0,("Got release IP message for our IP %s - exiting immediately\n",
1980                         ip));
1981                 /* note we must exit with non-zero status so the unclean handler gets
1982                    called in the parent, so that the brl database is tickled */
1983                 _exit(1);
1984         }
1985 }
1986
1987 static void msg_release_ip(struct messaging_context *msg_ctx, void *private_data,
1988                            uint32_t msg_type, struct server_id server_id, DATA_BLOB *data)
1989 {
1990         release_ip((char *)data->data, NULL);
1991 }
1992
1993 #ifdef CLUSTER_SUPPORT
1994 static int client_get_tcp_info(struct sockaddr_storage *server,
1995                                struct sockaddr_storage *client)
1996 {
1997         socklen_t length;
1998         if (server_fd == -1) {
1999                 return -1;
2000         }
2001         length = sizeof(*server);
2002         if (getsockname(server_fd, (struct sockaddr *)server, &length) != 0) {
2003                 return -1;
2004         }
2005         length = sizeof(*client);
2006         if (getpeername(server_fd, (struct sockaddr *)client, &length) != 0) {
2007                 return -1;
2008         }
2009         return 0;
2010 }
2011 #endif
2012
2013 /*
2014  * Send keepalive packets to our client
2015  */
2016 static bool keepalive_fn(const struct timeval *now, void *private_data)
2017 {
2018         if (!send_keepalive(smbd_server_fd())) {
2019                 DEBUG( 2, ( "Keepalive failed - exiting.\n" ) );
2020                 return False;
2021         }
2022         return True;
2023 }
2024
2025 /*
2026  * Do the recurring check if we're idle
2027  */
2028 static bool deadtime_fn(const struct timeval *now, void *private_data)
2029 {
2030         struct smbd_server_connection *sconn = smbd_server_conn;
2031         if ((conn_num_open(sconn) == 0)
2032             || (conn_idle_all(sconn, now->tv_sec))) {
2033                 DEBUG( 2, ( "Closing idle connection\n" ) );
2034                 messaging_send(smbd_messaging_context(), procid_self(),
2035                                MSG_SHUTDOWN, &data_blob_null);
2036                 return False;
2037         }
2038
2039         return True;
2040 }
2041
2042 /*
2043  * Do the recurring log file and smb.conf reload checks.
2044  */
2045
2046 static bool housekeeping_fn(const struct timeval *now, void *private_data)
2047 {
2048         change_to_root_user();
2049
2050         /* update printer queue caches if necessary */
2051         update_monitored_printq_cache();
2052
2053         /* check if we need to reload services */
2054         check_reload(time(NULL));
2055
2056         /* Change machine password if neccessary. */
2057         attempt_machine_password_change();
2058
2059         /*
2060          * Force a log file check.
2061          */
2062         force_check_log_size();
2063         check_log_size();
2064         return true;
2065 }
2066
2067 /****************************************************************************
2068  Process commands from the client
2069 ****************************************************************************/
2070
2071 void smbd_process(void)
2072 {
2073         TALLOC_CTX *frame = talloc_stackframe();
2074         char remaddr[INET6_ADDRSTRLEN];
2075
2076         if (lp_maxprotocol() == PROTOCOL_SMB2 &&
2077             lp_security() != SEC_SHARE) {
2078                 smbd_server_conn->allow_smb2 = true;
2079         }
2080
2081         /* Ensure child is set to blocking mode */
2082         set_blocking(smbd_server_fd(),True);
2083
2084         set_socket_options(smbd_server_fd(),"SO_KEEPALIVE");
2085         set_socket_options(smbd_server_fd(), lp_socket_options());
2086
2087         /* this is needed so that we get decent entries
2088            in smbstatus for port 445 connects */
2089         set_remote_machine_name(get_peer_addr(smbd_server_fd(),
2090                                               remaddr,
2091                                               sizeof(remaddr)),
2092                                               false);
2093         reload_services(true);
2094
2095         /*
2096          * Before the first packet, check the global hosts allow/ hosts deny
2097          * parameters before doing any parsing of packets passed to us by the
2098          * client. This prevents attacks on our parsing code from hosts not in
2099          * the hosts allow list.
2100          */
2101
2102         if (!check_access(smbd_server_fd(), lp_hostsallow(-1),
2103                           lp_hostsdeny(-1))) {
2104                 char addr[INET6_ADDRSTRLEN];
2105
2106                 /*
2107                  * send a negative session response "not listening on calling
2108                  * name"
2109                  */
2110                 unsigned char buf[5] = {0x83, 0, 0, 1, 0x81};
2111                 DEBUG( 1, ("Connection denied from %s\n",
2112                            client_addr(get_client_fd(),addr,sizeof(addr)) ) );
2113                 (void)srv_send_smb(smbd_server_fd(),(char *)buf, false,
2114                                    0, false, NULL);
2115                 exit_server_cleanly("connection denied");
2116         }
2117
2118         static_init_rpc;
2119
2120         init_modules();
2121
2122         smb_perfcount_init();
2123
2124         if (!init_account_policy()) {
2125                 exit_server("Could not open account policy tdb.\n");
2126         }
2127
2128         if (*lp_rootdir()) {
2129                 if (chroot(lp_rootdir()) != 0) {
2130                         DEBUG(0,("Failed to change root to %s\n", lp_rootdir()));
2131                         exit_server("Failed to chroot()");
2132                 }
2133                 if (chdir("/") == -1) {
2134                         DEBUG(0,("Failed to chdir to / on chroot to %s\n", lp_rootdir()));
2135                         exit_server("Failed to chroot()");
2136                 }
2137                 DEBUG(0,("Changed root to %s\n", lp_rootdir()));
2138         }
2139
2140         if (!srv_init_signing(smbd_server_conn)) {
2141                 exit_server("Failed to init smb_signing");
2142         }
2143
2144         /* Setup oplocks */
2145         if (!init_oplocks(smbd_messaging_context()))
2146                 exit_server("Failed to init oplocks");
2147
2148         /* Setup aio signal handler. */
2149         initialize_async_io_handler();
2150
2151         /* register our message handlers */
2152         messaging_register(smbd_messaging_context(), NULL,
2153                            MSG_SMB_FORCE_TDIS, msg_force_tdis);
2154         messaging_register(smbd_messaging_context(), NULL,
2155                            MSG_SMB_RELEASE_IP, msg_release_ip);
2156         messaging_register(smbd_messaging_context(), NULL,
2157                            MSG_SMB_CLOSE_FILE, msg_close_file);
2158
2159         /*
2160          * Use the default MSG_DEBUG handler to avoid rebroadcasting
2161          * MSGs to all child processes
2162          */
2163         messaging_deregister(smbd_messaging_context(),
2164                              MSG_DEBUG, NULL);
2165         messaging_register(smbd_messaging_context(), NULL,
2166                            MSG_DEBUG, debug_message);
2167
2168         if ((lp_keepalive() != 0)
2169             && !(event_add_idle(smbd_event_context(), NULL,
2170                                 timeval_set(lp_keepalive(), 0),
2171                                 "keepalive", keepalive_fn,
2172                                 NULL))) {
2173                 DEBUG(0, ("Could not add keepalive event\n"));
2174                 exit(1);
2175         }
2176
2177         if (!(event_add_idle(smbd_event_context(), NULL,
2178                              timeval_set(IDLE_CLOSED_TIMEOUT, 0),
2179                              "deadtime", deadtime_fn, NULL))) {
2180                 DEBUG(0, ("Could not add deadtime event\n"));
2181                 exit(1);
2182         }
2183
2184         if (!(event_add_idle(smbd_event_context(), NULL,
2185                              timeval_set(SMBD_SELECT_TIMEOUT, 0),
2186                              "housekeeping", housekeeping_fn, NULL))) {
2187                 DEBUG(0, ("Could not add housekeeping event\n"));
2188                 exit(1);
2189         }
2190
2191 #ifdef CLUSTER_SUPPORT
2192
2193         if (lp_clustering()) {
2194                 /*
2195                  * We need to tell ctdb about our client's TCP
2196                  * connection, so that for failover ctdbd can send
2197                  * tickle acks, triggering a reconnection by the
2198                  * client.
2199                  */
2200
2201                 struct sockaddr_storage srv, clnt;
2202
2203                 if (client_get_tcp_info(&srv, &clnt) == 0) {
2204
2205                         NTSTATUS status;
2206
2207                         status = ctdbd_register_ips(
2208                                 messaging_ctdbd_connection(),
2209                                 &srv, &clnt, release_ip, NULL);
2210
2211                         if (!NT_STATUS_IS_OK(status)) {
2212                                 DEBUG(0, ("ctdbd_register_ips failed: %s\n",
2213                                           nt_errstr(status)));
2214                         }
2215                 } else
2216                 {
2217                         DEBUG(0,("Unable to get tcp info for "
2218                                  "CTDB_CONTROL_TCP_CLIENT: %s\n",
2219                                  strerror(errno)));
2220                 }
2221         }
2222
2223 #endif
2224
2225         smbd_server_conn->nbt.got_session = false;
2226
2227         smbd_server_conn->smb1.negprot.max_recv = MIN(lp_maxxmit(),BUFFER_SIZE);
2228
2229         smbd_server_conn->smb1.sessions.done_sesssetup = false;
2230         smbd_server_conn->smb1.sessions.max_send = BUFFER_SIZE;
2231         smbd_server_conn->smb1.sessions.last_session_tag = UID_FIELD_INVALID;
2232         /* users from session setup */
2233         smbd_server_conn->smb1.sessions.session_userlist = NULL;
2234         /* workgroup from session setup. */
2235         smbd_server_conn->smb1.sessions.session_workgroup = NULL;
2236         /* this holds info on user ids that are already validated for this VC */
2237         smbd_server_conn->smb1.sessions.validated_users = NULL;
2238         smbd_server_conn->smb1.sessions.next_vuid = VUID_OFFSET;
2239         smbd_server_conn->smb1.sessions.num_validated_vuids = 0;
2240 #ifdef HAVE_NETGROUP
2241         smbd_server_conn->smb1.sessions.my_yp_domain = NULL;
2242 #endif
2243
2244         conn_init(smbd_server_conn);
2245         if (!init_dptrs(smbd_server_conn)) {
2246                 exit_server("init_dptrs() failed");
2247         }
2248
2249         smbd_server_conn->smb1.fde = event_add_fd(smbd_event_context(),
2250                                                   smbd_server_conn,
2251                                                   smbd_server_fd(),
2252                                                   EVENT_FD_READ,
2253                                                   smbd_server_connection_handler,
2254                                                   smbd_server_conn);
2255         if (!smbd_server_conn->smb1.fde) {
2256                 exit_server("failed to create smbd_server_connection fde");
2257         }
2258
2259         TALLOC_FREE(frame);
2260
2261         while (True) {
2262                 NTSTATUS status;
2263
2264                 frame = talloc_stackframe_pool(8192);
2265
2266                 errno = 0;
2267
2268                 status = smbd_server_connection_loop_once(smbd_server_conn);
2269                 if (!NT_STATUS_EQUAL(status, NT_STATUS_RETRY) &&
2270                     !NT_STATUS_IS_OK(status)) {
2271                         DEBUG(3, ("smbd_server_connection_loop_once failed: %s,"
2272                                   " exiting\n", nt_errstr(status)));
2273                         break;
2274                 }
2275
2276                 TALLOC_FREE(frame);
2277         }
2278
2279         exit_server_cleanly(NULL);
2280 }
2281
2282 bool req_is_in_chain(struct smb_request *req)
2283 {
2284         if (req->vwv != (uint16_t *)(req->inbuf+smb_vwv)) {
2285                 /*
2286                  * We're right now handling a subsequent request, so we must
2287                  * be in a chain
2288                  */
2289                 return true;
2290         }
2291
2292         if (!is_andx_req(req->cmd)) {
2293                 return false;
2294         }
2295
2296         if (req->wct < 2) {
2297                 /*
2298                  * Okay, an illegal request, but definitely not chained :-)
2299                  */
2300                 return false;
2301         }
2302
2303         return (CVAL(req->vwv+0, 0) != 0xFF);
2304 }