source3/libsmb/clientgen.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    SMB client generic functions
   4    Copyright (C) Andrew Tridgell 1994-1998
   5    Copyright (C) Jeremy Allison 2007.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22
  23 /*******************************************************************
  24  Setup the word count and byte count for a client smb message.
  25 ********************************************************************/
  26
  27 int cli_set_message(char *buf,int num_words,int num_bytes,bool zero)
  28 {
  29         if (zero && (num_words || num_bytes)) {
  30                 memset(buf + smb_size,'\0',num_words*2 + num_bytes);
  31         }
  32         SCVAL(buf,smb_wct,num_words);
  33         SSVAL(buf,smb_vwv + num_words*SIZEOFWORD,num_bytes);
  34         smb_setlen(buf,smb_size + num_words*2 + num_bytes - 4);
  35         return (smb_size + num_words*2 + num_bytes);
  36 }
  37
  38 /****************************************************************************
  39  Change the timeout (in milliseconds).
  40 ****************************************************************************/
  41
  42 unsigned int cli_set_timeout(struct cli_state *cli, unsigned int timeout)
  43 {
  44         unsigned int old_timeout = cli->timeout;
  45         cli->timeout = timeout;
  46         return old_timeout;
  47 }
  48
  49 /****************************************************************************
  50  Change the port number used to call on.
  51 ****************************************************************************/
  52
  53 void cli_set_port(struct cli_state *cli, int port)
  54 {
  55         cli->port = port;
  56 }
  57
  58 /****************************************************************************
  59  convenience routine to find if we negotiated ucs2
  60 ****************************************************************************/
  61
  62 bool cli_ucs2(struct cli_state *cli)
  63 {
  64         return ((cli->capabilities & CAP_UNICODE) != 0);
  65 }
  66
  67
  68 /****************************************************************************
  69  Read an smb from a fd ignoring all keepalive packets.
  70  The timeout is in milliseconds
  71
  72  This is exactly the same as receive_smb except that it never returns
  73  a session keepalive packet (just as receive_smb used to do).
  74  receive_smb was changed to return keepalives as the oplock processing means this call
  75  should never go into a blocking read.
  76 ****************************************************************************/
  77
  78 static ssize_t client_receive_smb(struct cli_state *cli, size_t maxlen)
  79 {
  80         size_t len;
  81
  82         for(;;) {
  83                 NTSTATUS status;
  84
  85                 set_smb_read_error(&cli->smb_rw_error, SMB_READ_OK);
  86
  87                 status = receive_smb_raw(cli->fd, cli->inbuf, cli->bufsize,
  88                                         cli->timeout, maxlen, &len);
  89                 if (!NT_STATUS_IS_OK(status)) {
  90                         DEBUG(10,("client_receive_smb failed\n"));
  91                         show_msg(cli->inbuf);
  92
  93                         if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
  94                                 set_smb_read_error(&cli->smb_rw_error,
  95                                                    SMB_READ_EOF);
  96                                 return -1;
  97                         }
  98
  99                         if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT)) {
 100                                 set_smb_read_error(&cli->smb_rw_error,
 101                                                    SMB_READ_TIMEOUT);
 102                                 return -1;
 103                         }
 104
 105                         set_smb_read_error(&cli->smb_rw_error, SMB_READ_ERROR);
 106                         return -1;
 107                 }
 108
 109                 /*
 110                  * I don't believe len can be < 0 with NT_STATUS_OK
 111                  * returned above, but this check doesn't hurt. JRA.
 112                  */
 113
 114                 if ((ssize_t)len < 0) {
 115                         return len;
 116                 }
 117
 118                 /* Ignore session keepalive packets. */
 119                 if(CVAL(cli->inbuf,0) != SMBkeepalive) {
 120                         break;
 121                 }
 122         }
 123
 124         if (cli_encryption_on(cli)) {
 125                 NTSTATUS status = cli_decrypt_message(cli);
 126                 if (!NT_STATUS_IS_OK(status)) {
 127                         DEBUG(0, ("SMB decryption failed on incoming packet! Error %s\n",
 128                                 nt_errstr(status)));
 129                         cli->smb_rw_error = SMB_READ_BAD_DECRYPT;
 130                         return -1;
 131                 }
 132         }
 133
 134         show_msg(cli->inbuf);
 135         return len;
 136 }
 137
 138 /****************************************************************************
 139  Recv an smb.
 140 ****************************************************************************/
 141
 142 bool cli_receive_smb(struct cli_state *cli)
 143 {
 144         ssize_t len;
 145
 146         /* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
 147         if (cli->fd == -1)
 148                 return false;
 149
 150  again:
 151         len = client_receive_smb(cli, 0);
 152
 153         if (len > 0) {
 154                 /* it might be an oplock break request */
 155                 if (!(CVAL(cli->inbuf, smb_flg) & FLAG_REPLY) &&
 156                     CVAL(cli->inbuf,smb_com) == SMBlockingX &&
 157                     SVAL(cli->inbuf,smb_vwv6) == 0 &&
 158                     SVAL(cli->inbuf,smb_vwv7) == 0) {
 159                         if (cli->oplock_handler) {
 160                                 int fnum = SVAL(cli->inbuf,smb_vwv2);
 161                                 unsigned char level = CVAL(cli->inbuf,smb_vwv3+1);
 162                                 if (!cli->oplock_handler(cli, fnum, level)) {
 163                                         return false;
 164                                 }
 165                         }
 166                         /* try to prevent loops */
 167                         SCVAL(cli->inbuf,smb_com,0xFF);
 168                         goto again;
 169                 }
 170         }
 171
 172         /* If the server is not responding, note that now */
 173         if (len < 0) {
 174                 DEBUG(0, ("Receiving SMB: Server stopped responding\n"));
 175                 close(cli->fd);
 176                 cli->fd = -1;
 177                 return false;
 178         }
 179
 180         if (!cli_check_sign_mac(cli, cli->inbuf)) {
 181                 /*
 182                  * If we get a signature failure in sessionsetup, then
 183                  * the server sometimes just reflects the sent signature
 184                  * back to us. Detect this and allow the upper layer to
 185                  * retrieve the correct Windows error message.
 186                  */
 187                 if (CVAL(cli->outbuf,smb_com) == SMBsesssetupX &&
 188                         (smb_len(cli->inbuf) > (smb_ss_field + 8 - 4)) &&
 189                         (SVAL(cli->inbuf,smb_flg2) & FLAGS2_SMB_SECURITY_SIGNATURES) &&
 190                         memcmp(&cli->outbuf[smb_ss_field],&cli->inbuf[smb_ss_field],8) == 0 &&
 191                         cli_is_error(cli)) {
 192
 193                         /*
 194                          * Reflected signature on login error.
 195                          * Set bad sig but don't close fd.
 196                          */
 197                         cli->smb_rw_error = SMB_READ_BAD_SIG;
 198                         return true;
 199                 }
 200
 201                 DEBUG(0, ("SMB Signature verification failed on incoming packet!\n"));
 202                 cli->smb_rw_error = SMB_READ_BAD_SIG;
 203                 close(cli->fd);
 204                 cli->fd = -1;
 205                 return false;
 206         };
 207         return true;
 208 }
 209
 210 /****************************************************************************
 211  Read the data portion of a readX smb.
 212  The timeout is in milliseconds
 213 ****************************************************************************/
 214
 215 ssize_t cli_receive_smb_data(struct cli_state *cli, char *buffer, size_t len)
 216 {
 217         NTSTATUS status;
 218
 219         set_smb_read_error(&cli->smb_rw_error, SMB_READ_OK);
 220
 221         status = read_socket_with_timeout(
 222                 cli->fd, buffer, len, len, cli->timeout, NULL);
 223         if (NT_STATUS_IS_OK(status)) {
 224                 return len;
 225         }
 226
 227         if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
 228                 set_smb_read_error(&cli->smb_rw_error, SMB_READ_EOF);
 229                 return -1;
 230         }
 231
 232         if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT)) {
 233                 set_smb_read_error(&cli->smb_rw_error, SMB_READ_TIMEOUT);
 234                 return -1;
 235         }
 236
 237         set_smb_read_error(&cli->smb_rw_error, SMB_READ_ERROR);
 238         return -1;
 239 }
 240
 241 static ssize_t write_socket(int fd, const char *buf, size_t len)
 242 {
 243         ssize_t ret=0;
 244
 245         DEBUG(6,("write_socket(%d,%d)\n",fd,(int)len));
 246         ret = write_data(fd,buf,len);
 247
 248         DEBUG(6,("write_socket(%d,%d) wrote %d\n",fd,(int)len,(int)ret));
 249         if(ret <= 0)
 250                 DEBUG(0,("write_socket: Error writing %d bytes to socket %d: ERRNO = %s\n",
 251                         (int)len, fd, strerror(errno) ));
 252
 253         return(ret);
 254 }
 255
 256 /****************************************************************************
 257  Send an smb to a fd.
 258 ****************************************************************************/
 259
 260 bool cli_send_smb(struct cli_state *cli)
 261 {
 262         size_t len;
 263         size_t nwritten=0;
 264         ssize_t ret;
 265         char *buf_out = cli->outbuf;
 266         bool enc_on = cli_encryption_on(cli);
 267
 268         /* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
 269         if (cli->fd == -1)
 270                 return false;
 271
 272         cli_calculate_sign_mac(cli, cli->outbuf);
 273
 274         if (enc_on) {
 275                 NTSTATUS status = cli_encrypt_message(cli, cli->outbuf,
 276                                                       &buf_out);
 277                 if (!NT_STATUS_IS_OK(status)) {
 278                         close(cli->fd);
 279                         cli->fd = -1;
 280                         cli->smb_rw_error = SMB_WRITE_ERROR;
 281                         DEBUG(0,("Error in encrypting client message. Error %s\n",
 282                                 nt_errstr(status) ));
 283                         return false;
 284                 }
 285         }
 286
 287         len = smb_len(buf_out) + 4;
 288
 289         while (nwritten < len) {
 290                 ret = write_socket(cli->fd,buf_out+nwritten,len - nwritten);
 291                 if (ret <= 0) {
 292                         if (enc_on) {
 293                                 cli_free_enc_buffer(cli, buf_out);
 294                         }
 295                         close(cli->fd);
 296                         cli->fd = -1;
 297                         cli->smb_rw_error = SMB_WRITE_ERROR;
 298                         DEBUG(0,("Error writing %d bytes to client. %d (%s)\n",
 299                                 (int)len,(int)ret, strerror(errno) ));
 300                         return false;
 301                 }
 302                 nwritten += ret;
 303         }
 304
 305         if (enc_on) {
 306                 cli_free_enc_buffer(cli, buf_out);
 307         }
 308
 309         /* Increment the mid so we can tell between responses. */
 310         cli->mid++;
 311         if (!cli->mid)
 312                 cli->mid++;
 313         return true;
 314 }
 315
 316 /****************************************************************************
 317  Send a "direct" writeX smb to a fd.
 318 ****************************************************************************/
 319
 320 bool cli_send_smb_direct_writeX(struct cli_state *cli,
 321                                 const char *p,
 322                                 size_t extradata)
 323 {
 324         /* First length to send is the offset to the data. */
 325         size_t len = SVAL(cli->outbuf,smb_vwv11) + 4;
 326         size_t nwritten=0;
 327         struct iovec iov[2];
 328
 329         /* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
 330         if (cli->fd == -1) {
 331                 return false;
 332         }
 333
 334         if (client_is_signing_on(cli)) {
 335                 DEBUG(0,("cli_send_smb_large: cannot send signed packet.\n"));
 336                 return false;
 337         }
 338
 339         iov[0].iov_base = cli->outbuf;
 340         iov[0].iov_len = len;
 341         iov[1].iov_base = CONST_DISCARD(char *, p);
 342         iov[1].iov_len = extradata;
 343
 344         nwritten = write_data_iov(cli->fd, iov, 2);
 345         if (nwritten < (len + extradata)) {
 346                 close(cli->fd);
 347                 cli->fd = -1;
 348                 cli->smb_rw_error = SMB_WRITE_ERROR;
 349                 DEBUG(0,("Error writing %d bytes to client. (%s)\n",
 350                          (int)(len+extradata), strerror(errno)));
 351                 return false;
 352         }
 353
 354         /* Increment the mid so we can tell between responses. */
 355         cli->mid++;
 356         if (!cli->mid)
 357                 cli->mid++;
 358         return true;
 359 }
 360
 361 /****************************************************************************
 362  Setup basics in a outgoing packet.
 363 ****************************************************************************/
 364
 365 void cli_setup_packet_buf(struct cli_state *cli, char *buf)
 366 {
 367         uint16 flags2;
 368         cli->rap_error = 0;
 369         SIVAL(buf,smb_rcls,0);
 370         SSVAL(buf,smb_pid,cli->pid);
 371         memset(buf+smb_pidhigh, 0, 12);
 372         SSVAL(buf,smb_uid,cli->vuid);
 373         SSVAL(buf,smb_mid,cli->mid);
 374
 375         if (cli->protocol <= PROTOCOL_CORE) {
 376                 return;
 377         }
 378
 379         if (cli->case_sensitive) {
 380                 SCVAL(buf,smb_flg,0x0);
 381         } else {
 382                 /* Default setting, case insensitive. */
 383                 SCVAL(buf,smb_flg,0x8);
 384         }
 385         flags2 = FLAGS2_LONG_PATH_COMPONENTS;
 386         if (cli->capabilities & CAP_UNICODE)
 387                 flags2 |= FLAGS2_UNICODE_STRINGS;
 388         if ((cli->capabilities & CAP_DFS) && cli->dfsroot)
 389                 flags2 |= FLAGS2_DFS_PATHNAMES;
 390         if (cli->capabilities & CAP_STATUS32)
 391                 flags2 |= FLAGS2_32_BIT_ERROR_CODES;
 392         if (cli->use_spnego)
 393                 flags2 |= FLAGS2_EXTENDED_SECURITY;
 394         SSVAL(buf,smb_flg2, flags2);
 395 }
 396
 397 void cli_setup_packet(struct cli_state *cli)
 398 {
 399         cli_setup_packet_buf(cli, cli->outbuf);
 400 }
 401
 402 /****************************************************************************
 403  Setup the bcc length of the packet from a pointer to the end of the data.
 404 ****************************************************************************/
 405
 406 void cli_setup_bcc(struct cli_state *cli, void *p)
 407 {
 408         set_message_bcc(cli->outbuf, PTR_DIFF(p, smb_buf(cli->outbuf)));
 409 }
 410
 411 /****************************************************************************
 412  Initialise credentials of a client structure.
 413 ****************************************************************************/
 414
 415 void cli_init_creds(struct cli_state *cli, const char *username, const char *domain, const char *password)
 416 {
 417         fstrcpy(cli->domain, domain);
 418         fstrcpy(cli->user_name, username);
 419         pwd_set_cleartext(&cli->pwd, password);
 420         if (!*username) {
 421                 cli->pwd.null_pwd = true;
 422         }
 423
 424         DEBUG(10,("cli_init_creds: user %s domain %s\n", cli->user_name, cli->domain));
 425 }
 426
 427 /****************************************************************************
 428  Initialise a client structure. Always returns a malloc'ed struct.
 429  Set the signing state (used from the command line).
 430 ****************************************************************************/
 431
 432 struct cli_state *cli_initialise_ex(int signing_state)
 433 {
 434         struct cli_state *cli = NULL;
 435         bool allow_smb_signing = false;
 436         bool mandatory_signing = false;
 437
 438         /* Check the effective uid - make sure we are not setuid */
 439         if (is_setuid_root()) {
 440                 DEBUG(0,("libsmb based programs must *NOT* be setuid root.\n"));
 441                 return NULL;
 442         }
 443
 444         cli = TALLOC_ZERO_P(NULL, struct cli_state);
 445         if (!cli) {
 446                 return NULL;
 447         }
 448
 449         cli->port = 0;
 450         cli->fd = -1;
 451         cli->cnum = -1;
 452         cli->pid = (uint16)sys_getpid();
 453         cli->mid = 1;
 454         cli->vuid = UID_FIELD_INVALID;
 455         cli->protocol = PROTOCOL_NT1;
 456         cli->timeout = 20000; /* Timeout is in milliseconds. */
 457         cli->bufsize = CLI_BUFFER_SIZE+4;
 458         cli->max_xmit = cli->bufsize;
 459         cli->outbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
 460         cli->inbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
 461         cli->oplock_handler = cli_oplock_ack;
 462         cli->case_sensitive = false;
 463         cli->smb_rw_error = SMB_READ_OK;
 464
 465         cli->use_spnego = lp_client_use_spnego();
 466
 467         cli->capabilities = CAP_UNICODE | CAP_STATUS32 | CAP_DFS;
 468
 469         /* Set the CLI_FORCE_DOSERR environment variable to test
 470            client routines using DOS errors instead of STATUS32
 471            ones.  This intended only as a temporary hack. */
 472         if (getenv("CLI_FORCE_DOSERR"))
 473                 cli->force_dos_errors = true;
 474
 475         if (lp_client_signing()) {
 476                 allow_smb_signing = true;
 477         }
 478
 479         if (lp_client_signing() == Required) {
 480                 mandatory_signing = true;
 481         }
 482
 483         if (signing_state != Undefined) {
 484                 allow_smb_signing = true;
 485         }
 486
 487         if (signing_state == false) {
 488                 allow_smb_signing = false;
 489                 mandatory_signing = false;
 490         }
 491
 492         if (signing_state == Required) {
 493                 mandatory_signing = true;
 494         }
 495
 496         if (!cli->outbuf || !cli->inbuf)
 497                 goto error;
 498
 499         memset(cli->outbuf, 0, cli->bufsize);
 500         memset(cli->inbuf, 0, cli->bufsize);
 501
 502
 503 #if defined(DEVELOPER)
 504         /* just because we over-allocate, doesn't mean it's right to use it */
 505         clobber_region(FUNCTION_MACRO, __LINE__, cli->outbuf+cli->bufsize, SAFETY_MARGIN);
 506         clobber_region(FUNCTION_MACRO, __LINE__, cli->inbuf+cli->bufsize, SAFETY_MARGIN);
 507 #endif
 508
 509         /* initialise signing */
 510         cli->sign_info.allow_smb_signing = allow_smb_signing;
 511         cli->sign_info.mandatory_signing = mandatory_signing;
 512         cli_null_set_signing(cli);
 513
 514         cli->initialised = 1;
 515
 516         return cli;
 517
 518         /* Clean up after malloc() error */
 519
 520  error:
 521
 522         SAFE_FREE(cli->inbuf);
 523         SAFE_FREE(cli->outbuf);
 524         SAFE_FREE(cli);
 525         return NULL;
 526 }
 527
 528 struct cli_state *cli_initialise(void)
 529 {
 530         return cli_initialise_ex(Undefined);
 531 }
 532
 533 /****************************************************************************
 534  Close all pipes open on this session.
 535 ****************************************************************************/
 536
 537 void cli_nt_pipes_close(struct cli_state *cli)
 538 {
 539         while (cli->pipe_list != NULL) {
 540                 /*
 541                  * No TALLOC_FREE here!
 542                  */
 543                 talloc_free(cli->pipe_list);
 544         }
 545 }
 546
 547 /****************************************************************************
 548  Shutdown a client structure.
 549 ****************************************************************************/
 550
 551 void cli_shutdown(struct cli_state *cli)
 552 {
 553         cli_nt_pipes_close(cli);
 554
 555         /*
 556          * tell our peer to free his resources.  Wihtout this, when an
 557          * application attempts to do a graceful shutdown and calls
 558          * smbc_free_context() to clean up all connections, some connections
 559          * can remain active on the peer end, until some (long) timeout period
 560          * later.  This tree disconnect forces the peer to clean up, since the
 561          * connection will be going away.
 562          *
 563          * Also, do not do tree disconnect when cli->smb_rw_error is SMB_DO_NOT_DO_TDIS
 564          * the only user for this so far is smbmount which passes opened connection
 565          * down to kernel's smbfs module.
 566          */
 567         if ( (cli->cnum != (uint16)-1) && (cli->smb_rw_error != SMB_DO_NOT_DO_TDIS ) ) {
 568                 cli_tdis(cli);
 569         }
 570
 571         SAFE_FREE(cli->outbuf);
 572         SAFE_FREE(cli->inbuf);
 573
 574         cli_free_signing_context(cli);
 575         data_blob_free(&cli->secblob);
 576         data_blob_free(&cli->user_session_key);
 577
 578         if (cli->fd != -1) {
 579                 close(cli->fd);
 580         }
 581         cli->fd = -1;
 582         cli->smb_rw_error = SMB_READ_OK;
 583
 584         TALLOC_FREE(cli);
 585 }
 586
 587 /****************************************************************************
 588  Set socket options on a open connection.
 589 ****************************************************************************/
 590
 591 void cli_sockopt(struct cli_state *cli, const char *options)
 592 {
 593         set_socket_options(cli->fd, options);
 594 }
 595
 596 /****************************************************************************
 597  Set the PID to use for smb messages. Return the old pid.
 598 ****************************************************************************/
 599
 600 uint16 cli_setpid(struct cli_state *cli, uint16 pid)
 601 {
 602         uint16 ret = cli->pid;
 603         cli->pid = pid;
 604         return ret;
 605 }
 606
 607 /****************************************************************************
 608  Set the case sensitivity flag on the packets. Returns old state.
 609 ****************************************************************************/
 610
 611 bool cli_set_case_sensitive(struct cli_state *cli, bool case_sensitive)
 612 {
 613         bool ret = cli->case_sensitive;
 614         cli->case_sensitive = case_sensitive;
 615         return ret;
 616 }
 617
 618 /****************************************************************************
 619 Send a keepalive packet to the server
 620 ****************************************************************************/
 621
 622 bool cli_send_keepalive(struct cli_state *cli)
 623 {
 624         if (cli->fd == -1) {
 625                 DEBUG(3, ("cli_send_keepalive: fd == -1\n"));
 626                 return false;
 627         }
 628         if (!send_keepalive(cli->fd)) {
 629                 close(cli->fd);
 630                 cli->fd = -1;
 631                 DEBUG(0,("Error sending keepalive packet to client.\n"));
 632                 return false;
 633         }
 634         return true;
 635 }
 636
 637 /**
 638  * @brief: Collect a echo reply
 639  * @param[in] req       The corresponding async request
 640  *
 641  * There might be more than one echo reply. This helper pulls the reply out of
 642  * the data stream. If all expected replies have arrived, declare the
 643  * async_req done.
 644  */
 645
 646 static void cli_echo_recv_helper(struct async_req *req)
 647 {
 648         struct cli_request *cli_req;
 649         uint8_t wct;
 650         uint16_t *vwv;
 651         uint16_t num_bytes;
 652         uint8_t *bytes;
 653         NTSTATUS status;
 654
 655         status = cli_pull_reply(req, &wct, &vwv, &num_bytes, &bytes);
 656         if (!NT_STATUS_IS_OK(status)) {
 657                 async_req_nterror(req, status);
 658                 return;
 659         }
 660
 661         cli_req = talloc_get_type_abort(req->private_data, struct cli_request);
 662
 663         if ((num_bytes != cli_req->data.echo.data.length)
 664             || (memcmp(cli_req->data.echo.data.data, bytes,
 665                        num_bytes) != 0)) {
 666                 async_req_nterror(req, NT_STATUS_INVALID_NETWORK_RESPONSE);
 667                 return;
 668         }
 669
 670         cli_req->data.echo.num_echos -= 1;
 671
 672         if (cli_req->data.echo.num_echos == 0) {
 673                 client_set_trans_sign_state_off(cli_req->cli, cli_req->mid);
 674                 async_req_done(req);
 675                 return;
 676         }
 677
 678         return;
 679 }
 680
 681 /**
 682  * @brief Send SMBEcho requests
 683  * @param[in] mem_ctx   The memory context to put the async_req on
 684  * @param[in] ev        The event context that will call us back
 685  * @param[in] cli       The connection to send the echo to
 686  * @param[in] num_echos How many times do we want to get the reply?
 687  * @param[in] data      The data we want to get back
 688  * @retval The async request
 689  */
 690
 691 struct async_req *cli_echo_send(TALLOC_CTX *mem_ctx, struct event_context *ev,
 692                                 struct cli_state *cli, uint16_t num_echos,
 693                                 DATA_BLOB data)
 694 {
 695         uint16_t vwv[1];
 696         uint8_t *data_copy;
 697         struct async_req *result;
 698         struct cli_request *req;
 699
 700         SSVAL(vwv, 0, num_echos);
 701
 702         data_copy = (uint8_t *)talloc_memdup(mem_ctx, data.data, data.length);
 703         if (data_copy == NULL) {
 704                 return NULL;
 705         }
 706
 707         result = cli_request_send(mem_ctx, ev, cli, SMBecho, 0, 1, vwv, 0,
 708                                   data.length, data.data);
 709         if (result == NULL) {
 710                 TALLOC_FREE(data_copy);
 711                 return NULL;
 712         }
 713         req = talloc_get_type_abort(result->private_data, struct cli_request);
 714
 715         client_set_trans_sign_state_on(cli, req->mid);
 716
 717         req->data.echo.num_echos = num_echos;
 718         req->data.echo.data.data = talloc_move(req, &data_copy);
 719         req->data.echo.data.length = data.length;
 720
 721         req->recv_helper.fn = cli_echo_recv_helper;
 722
 723         return result;
 724 }
 725
 726 /**
 727  * Get the result out from an echo request
 728  * @param[in] req       The async_req from cli_echo_send
 729  * @retval Did the server reply correctly?
 730  */
 731
 732 NTSTATUS cli_echo_recv(struct async_req *req)
 733 {
 734         return async_req_simple_recv_ntstatus(req);
 735 }
 736
 737 /**
 738  * @brief Send/Receive SMBEcho requests
 739  * @param[in] mem_ctx   The memory context to put the async_req on
 740  * @param[in] ev        The event context that will call us back
 741  * @param[in] cli       The connection to send the echo to
 742  * @param[in] num_echos How many times do we want to get the reply?
 743  * @param[in] data      The data we want to get back
 744  * @retval Did the server reply correctly?
 745  */
 746
 747 NTSTATUS cli_echo(struct cli_state *cli, uint16_t num_echos, DATA_BLOB data)
 748 {
 749         TALLOC_CTX *frame = talloc_stackframe();
 750         struct event_context *ev;
 751         struct async_req *req;
 752         NTSTATUS status = NT_STATUS_NO_MEMORY;
 753
 754         if (cli->fd_event != NULL) {
 755                 /*
 756                  * Can't use sync call while an async call is in flight
 757                  */
 758                 cli_set_error(cli, NT_STATUS_INVALID_PARAMETER);
 759                 goto fail;
 760         }
 761
 762         ev = event_context_init(frame);
 763         if (ev == NULL) {
 764                 goto fail;
 765         }
 766
 767         req = cli_echo_send(frame, ev, cli, num_echos, data);
 768         if (req == NULL) {
 769                 goto fail;
 770         }
 771
 772         while (req->state < ASYNC_REQ_DONE) {
 773                 event_loop_once(ev);
 774         }
 775
 776         status = cli_echo_recv(req);
 777
 778  fail:
 779         TALLOC_FREE(frame);
 780         return status;
 781 }
 782
 783 /**
 784  * Is the SMB command able to hold an AND_X successor
 785  * @param[in] cmd       The SMB command in question
 786  * @retval Can we add a chained request after "cmd"?
 787  */
 788 bool is_andx_req(uint8_t cmd)
 789 {
 790         switch (cmd) {
 791         case SMBtconX:
 792         case SMBlockingX:
 793         case SMBopenX:
 794         case SMBreadX:
 795         case SMBwriteX:
 796         case SMBsesssetupX:
 797         case SMBulogoffX:
 798         case SMBntcreateX:
 799                 return true;
 800                 break;
 801         default:
 802                 break;
 803         }
 804
 805         return false;
 806 }