source/libsmb/clientgen.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    SMB client generic functions
   4    Copyright (C) Andrew Tridgell 1994-1998
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "includes.h"
  22
  23 extern int smb_read_error;
  24
  25 /****************************************************************************
  26  Change the timeout (in milliseconds).
  27 ****************************************************************************/
  28
  29 unsigned int cli_set_timeout(struct cli_state *cli, unsigned int timeout)
  30 {
  31         unsigned int old_timeout = cli->timeout;
  32         cli->timeout = timeout;
  33         return old_timeout;
  34 }
  35
  36 /****************************************************************************
  37  Change the port number used to call on.
  38 ****************************************************************************/
  39
  40 int cli_set_port(struct cli_state *cli, int port)
  41 {
  42         cli->port = port;
  43         return port;
  44 }
  45
  46 /****************************************************************************
  47  Read an smb from a fd ignoring all keepalive packets. Note that the buffer
  48  *MUST* be of size BUFFER_SIZE+SAFETY_MARGIN.
  49  The timeout is in milliseconds
  50
  51  This is exactly the same as receive_smb except that it never returns
  52  a session keepalive packet (just as receive_smb used to do).
  53  receive_smb was changed to return keepalives as the oplock processing means this call
  54  should never go into a blocking read.
  55 ****************************************************************************/
  56
  57 static BOOL client_receive_smb(struct cli_state *cli)
  58 {
  59         BOOL ret;
  60         int fd = cli->fd;
  61         char *buffer = cli->inbuf;
  62         unsigned int timeout = cli->timeout;
  63
  64         for(;;) {
  65                 ret = receive_smb_raw(fd, buffer, timeout);
  66
  67                 if (!ret) {
  68                         DEBUG(10,("client_receive_smb failed\n"));
  69                         show_msg(buffer);
  70                         return ret;
  71                 }
  72
  73                 /* Ignore session keepalive packets. */
  74                 if(CVAL(buffer,0) != SMBkeepalive)
  75                         break;
  76         }
  77
  78         if (cli_encryption_on(cli)) {
  79                 NTSTATUS status = cli_decrypt_message(cli);
  80                 if (!NT_STATUS_IS_OK(status)) {
  81                         DEBUG(0, ("SMB decryption failed on incoming packet! Error %s\n",
  82                                 nt_errstr(status)));
  83                         cli->smb_rw_error = READ_BAD_DECRYPT;
  84                         close(cli->fd);
  85                         cli->fd = -1;
  86                         return False;
  87                 }
  88         }
  89         show_msg(buffer);
  90         return ret;
  91 }
  92
  93 /****************************************************************************
  94  Recv an smb.
  95 ****************************************************************************/
  96
  97 BOOL cli_receive_smb(struct cli_state *cli)
  98 {
  99         BOOL ret;
 100
 101         /* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
 102         if (cli->fd == -1)
 103                 return False;
 104
 105  again:
 106         ret = client_receive_smb(cli);
 107
 108         if (ret) {
 109                 /* it might be an oplock break request */
 110                 if (!(CVAL(cli->inbuf, smb_flg) & FLAG_REPLY) &&
 111                     CVAL(cli->inbuf,smb_com) == SMBlockingX &&
 112                     SVAL(cli->inbuf,smb_vwv6) == 0 &&
 113                     SVAL(cli->inbuf,smb_vwv7) == 0) {
 114                         if (cli->oplock_handler) {
 115                                 int fnum = SVAL(cli->inbuf,smb_vwv2);
 116                                 unsigned char level = CVAL(cli->inbuf,smb_vwv3+1);
 117                                 if (!cli->oplock_handler(cli, fnum, level)) return False;
 118                         }
 119                         /* try to prevent loops */
 120                         SCVAL(cli->inbuf,smb_com,0xFF);
 121                         goto again;
 122                 }
 123         }
 124
 125         /* If the server is not responding, note that now */
 126         if (!ret) {
 127                 DEBUG(0, ("Receiving SMB: Server stopped responding\n"));
 128                 cli->smb_rw_error = smb_read_error;
 129                 close(cli->fd);
 130                 cli->fd = -1;
 131                 return ret;
 132         }
 133
 134         if (!cli_check_sign_mac(cli)) {
 135                 DEBUG(0, ("SMB Signature verification failed on incoming packet!\n"));
 136                 cli->smb_rw_error = READ_BAD_SIG;
 137                 close(cli->fd);
 138                 cli->fd = -1;
 139                 return False;
 140         }
 141
 142         return True;
 143 }
 144
 145 static ssize_t write_socket(int fd, const char *buf, size_t len)
 146 {
 147         ssize_t ret=0;
 148
 149         DEBUG(6,("write_socket(%d,%d)\n",fd,(int)len));
 150         ret = write_data(fd,buf,len);
 151
 152         DEBUG(6,("write_socket(%d,%d) wrote %d\n",fd,(int)len,(int)ret));
 153         if(ret <= 0)
 154                 DEBUG(0,("write_socket: Error writing %d bytes to socket %d: ERRNO = %s\n",
 155                         (int)len, fd, strerror(errno) ));
 156
 157         return(ret);
 158 }
 159
 160 /****************************************************************************
 161  Send an smb to a fd.
 162 ****************************************************************************/
 163
 164 BOOL cli_send_smb(struct cli_state *cli)
 165 {
 166         size_t len;
 167         size_t nwritten=0;
 168         ssize_t ret;
 169         char *buf_out = cli->outbuf;
 170
 171         /* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
 172         if (cli->fd == -1) {
 173                 return False;
 174         }
 175
 176         cli_calculate_sign_mac(cli);
 177
 178         if (cli_encryption_on(cli)) {
 179                 NTSTATUS status = cli_encrypt_message(cli, &buf_out);
 180                 if (!NT_STATUS_IS_OK(status)) {
 181                         close(cli->fd);
 182                         cli->fd = -1;
 183                         cli->smb_rw_error = WRITE_ERROR;
 184                         DEBUG(0,("Error in encrypting client message. Error %s\n",
 185                                 nt_errstr(status) ));
 186                         return False;
 187                 }
 188         }
 189
 190         len = smb_len(buf_out) + 4;
 191
 192         while (nwritten < len) {
 193                 ret = write_socket(cli->fd,buf_out+nwritten,len - nwritten);
 194                 if (ret <= 0) {
 195                         cli_free_enc_buffer(cli, buf_out);
 196                         close(cli->fd);
 197                         cli->fd = -1;
 198                         cli->smb_rw_error = WRITE_ERROR;
 199                         DEBUG(0,("Error writing %d bytes to client. %d (%s)\n",
 200                                 (int)len,(int)ret, strerror(errno) ));
 201                         return False;
 202                 }
 203                 nwritten += ret;
 204         }
 205
 206         cli_free_enc_buffer(cli, buf_out);
 207
 208         /* Increment the mid so we can tell between responses. */
 209         cli->mid++;
 210         if (!cli->mid) {
 211                 cli->mid++;
 212         }
 213         return True;
 214 }
 215
 216 /****************************************************************************
 217  Setup basics in a outgoing packet.
 218 ****************************************************************************/
 219
 220 void cli_setup_packet(struct cli_state *cli)
 221 {
 222         cli->rap_error = 0;
 223         SSVAL(cli->outbuf,smb_pid,cli->pid);
 224         SSVAL(cli->outbuf,smb_uid,cli->vuid);
 225         SSVAL(cli->outbuf,smb_mid,cli->mid);
 226         if (cli->protocol > PROTOCOL_CORE) {
 227                 uint16 flags2;
 228                 if (cli->case_sensitive) {
 229                         SCVAL(cli->outbuf,smb_flg,0x0);
 230                 } else {
 231                         /* Default setting, case insensitive. */
 232                         SCVAL(cli->outbuf,smb_flg,0x8);
 233                 }
 234                 flags2 = FLAGS2_LONG_PATH_COMPONENTS;
 235                 if (cli->capabilities & CAP_UNICODE)
 236                         flags2 |= FLAGS2_UNICODE_STRINGS;
 237                 if ((cli->capabilities & CAP_DFS) && cli->dfsroot)
 238                         flags2 |= FLAGS2_DFS_PATHNAMES;
 239                 if (cli->capabilities & CAP_STATUS32)
 240                         flags2 |= FLAGS2_32_BIT_ERROR_CODES;
 241                 if (cli->use_spnego)
 242                         flags2 |= FLAGS2_EXTENDED_SECURITY;
 243                 SSVAL(cli->outbuf,smb_flg2, flags2);
 244         }
 245 }
 246
 247 /****************************************************************************
 248  Setup the bcc length of the packet from a pointer to the end of the data.
 249 ****************************************************************************/
 250
 251 void cli_setup_bcc(struct cli_state *cli, void *p)
 252 {
 253         set_message_bcc(cli->outbuf, PTR_DIFF(p, smb_buf(cli->outbuf)));
 254 }
 255
 256 /****************************************************************************
 257  Initialise credentials of a client structure.
 258 ****************************************************************************/
 259
 260 void cli_init_creds(struct cli_state *cli, const char *username, const char *domain, const char *password)
 261 {
 262         fstrcpy(cli->domain, domain);
 263         fstrcpy(cli->user_name, username);
 264         pwd_set_cleartext(&cli->pwd, password);
 265         if (!*username) {
 266                 cli->pwd.null_pwd = True;
 267         }
 268
 269         DEBUG(10,("cli_init_creds: user %s domain %s\n", cli->user_name, cli->domain));
 270 }
 271
 272 /****************************************************************************
 273  Set the signing state (used from the command line).
 274 ****************************************************************************/
 275
 276 void cli_setup_signing_state(struct cli_state *cli, int signing_state)
 277 {
 278         if (signing_state == Undefined)
 279                 return;
 280
 281         if (signing_state == False) {
 282                 cli->sign_info.allow_smb_signing = False;
 283                 cli->sign_info.mandatory_signing = False;
 284                 return;
 285         }
 286
 287         cli->sign_info.allow_smb_signing = True;
 288
 289         if (signing_state == Required)
 290                 cli->sign_info.mandatory_signing = True;
 291 }
 292
 293 /****************************************************************************
 294  Initialise a client structure. Always returns a malloc'ed struct.
 295 ****************************************************************************/
 296
 297 struct cli_state *cli_initialise(void)
 298 {
 299         struct cli_state *cli = NULL;
 300
 301         /* Check the effective uid - make sure we are not setuid */
 302         if (is_setuid_root()) {
 303                 DEBUG(0,("libsmb based programs must *NOT* be setuid root.\n"));
 304                 return NULL;
 305         }
 306
 307         cli = SMB_MALLOC_P(struct cli_state);
 308         if (!cli) {
 309                 return NULL;
 310         }
 311
 312         ZERO_STRUCTP(cli);
 313
 314         cli->port = 0;
 315         cli->fd = -1;
 316         cli->cnum = -1;
 317         cli->pid = (uint16)sys_getpid();
 318         cli->mid = 1;
 319         cli->vuid = UID_FIELD_INVALID;
 320         cli->protocol = PROTOCOL_NT1;
 321         cli->timeout = 20000; /* Timeout is in milliseconds. */
 322         cli->bufsize = CLI_BUFFER_SIZE+4;
 323         cli->max_xmit = cli->bufsize;
 324         cli->outbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
 325         cli->inbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
 326         cli->oplock_handler = cli_oplock_ack;
 327         cli->case_sensitive = False;
 328         cli->smb_rw_error = 0;
 329
 330         cli->use_spnego = lp_client_use_spnego();
 331
 332         cli->capabilities = CAP_UNICODE | CAP_STATUS32 | CAP_DFS;
 333
 334         /* Set the CLI_FORCE_DOSERR environment variable to test
 335            client routines using DOS errors instead of STATUS32
 336            ones.  This intended only as a temporary hack. */
 337         if (getenv("CLI_FORCE_DOSERR"))
 338                 cli->force_dos_errors = True;
 339
 340         if (lp_client_signing())
 341                 cli->sign_info.allow_smb_signing = True;
 342
 343         if (lp_client_signing() == Required)
 344                 cli->sign_info.mandatory_signing = True;
 345
 346         if (!cli->outbuf || !cli->inbuf)
 347                 goto error;
 348
 349         if ((cli->mem_ctx = talloc_init("cli based talloc")) == NULL)
 350                 goto error;
 351
 352         memset(cli->outbuf, 0, cli->bufsize);
 353         memset(cli->inbuf, 0, cli->bufsize);
 354
 355
 356 #if defined(DEVELOPER)
 357         /* just because we over-allocate, doesn't mean it's right to use it */
 358         clobber_region(FUNCTION_MACRO, __LINE__, cli->outbuf+cli->bufsize, SAFETY_MARGIN);
 359         clobber_region(FUNCTION_MACRO, __LINE__, cli->inbuf+cli->bufsize, SAFETY_MARGIN);
 360 #endif
 361
 362         /* initialise signing */
 363         cli_null_set_signing(cli);
 364
 365         cli->initialised = 1;
 366
 367         return cli;
 368
 369         /* Clean up after malloc() error */
 370
 371  error:
 372
 373         SAFE_FREE(cli->inbuf);
 374         SAFE_FREE(cli->outbuf);
 375         SAFE_FREE(cli);
 376         return NULL;
 377 }
 378
 379 /****************************************************************************
 380  External interface.
 381  Close an open named pipe over SMB. Free any authentication data.
 382  Returns False if the cli_close call failed.
 383  ****************************************************************************/
 384
 385 BOOL cli_rpc_pipe_close(struct rpc_pipe_client *cli)
 386 {
 387         BOOL ret;
 388
 389         if (!cli) {
 390                 return False;
 391         }
 392
 393         ret = cli_close(cli->cli, cli->fnum);
 394
 395         if (!ret) {
 396                 DEBUG(1,("cli_rpc_pipe_close: cli_close failed on pipe %s, "
 397                          "fnum 0x%x "
 398                          "to machine %s.  Error was %s\n",
 399                          cli->pipe_name,
 400                          (int) cli->fnum,
 401                          cli->cli->desthost,
 402                          cli_errstr(cli->cli)));
 403         }
 404
 405         if (cli->auth.cli_auth_data_free_func) {
 406                 (*cli->auth.cli_auth_data_free_func)(&cli->auth);
 407         }
 408
 409         DEBUG(10,("cli_rpc_pipe_close: closed pipe %s to machine %s\n",
 410                 cli->pipe_name, cli->cli->desthost ));
 411
 412         DLIST_REMOVE(cli->cli->pipe_list, cli);
 413         talloc_destroy(cli->mem_ctx);
 414         return ret;
 415 }
 416
 417 /****************************************************************************
 418  Close all pipes open on this session.
 419 ****************************************************************************/
 420
 421 void cli_nt_pipes_close(struct cli_state *cli)
 422 {
 423         struct rpc_pipe_client *cp, *next;
 424
 425         for (cp = cli->pipe_list; cp; cp = next) {
 426                 next = cp->next;
 427                 cli_rpc_pipe_close(cp);
 428         }
 429 }
 430
 431 /****************************************************************************
 432  Shutdown a client structure.
 433 ****************************************************************************/
 434
 435 void cli_shutdown(struct cli_state *cli)
 436 {
 437         cli_nt_pipes_close(cli);
 438
 439         /*
 440          * tell our peer to free his resources.  Wihtout this, when an
 441          * application attempts to do a graceful shutdown and calls
 442          * smbc_free_context() to clean up all connections, some connections
 443          * can remain active on the peer end, until some (long) timeout period
 444          * later.  This tree disconnect forces the peer to clean up, since the
 445          * connection will be going away.
 446          *
 447          * Also, do not do tree disconnect when cli->smb_rw_error is DO_NOT_DO_TDIS
 448          * the only user for this so far is smbmount which passes opened connection
 449          * down to kernel's smbfs module.
 450          */
 451         if ( (cli->cnum != (uint16)-1) && (cli->smb_rw_error != DO_NOT_DO_TDIS ) ) {
 452                 cli_tdis(cli);
 453         }
 454
 455         SAFE_FREE(cli->outbuf);
 456         SAFE_FREE(cli->inbuf);
 457
 458         cli_free_signing_context(cli);
 459         cli_free_encryption_context(cli);
 460
 461         data_blob_free(&cli->secblob);
 462         data_blob_free(&cli->user_session_key);
 463
 464         if (cli->mem_ctx) {
 465                 talloc_destroy(cli->mem_ctx);
 466                 cli->mem_ctx = NULL;
 467         }
 468
 469         if (cli->fd != -1) {
 470                 close(cli->fd);
 471         }
 472         cli->fd = -1;
 473         cli->smb_rw_error = 0;
 474
 475         SAFE_FREE(cli);
 476 }
 477
 478 /****************************************************************************
 479  Set socket options on a open connection.
 480 ****************************************************************************/
 481
 482 void cli_sockopt(struct cli_state *cli, const char *options)
 483 {
 484         set_socket_options(cli->fd, options);
 485 }
 486
 487 /****************************************************************************
 488  Set the PID to use for smb messages. Return the old pid.
 489 ****************************************************************************/
 490
 491 uint16 cli_setpid(struct cli_state *cli, uint16 pid)
 492 {
 493         uint16 ret = cli->pid;
 494         cli->pid = pid;
 495         return ret;
 496 }
 497
 498 /****************************************************************************
 499  Set the case sensitivity flag on the packets. Returns old state.
 500 ****************************************************************************/
 501
 502 BOOL cli_set_case_sensitive(struct cli_state *cli, BOOL case_sensitive)
 503 {
 504         BOOL ret = cli->case_sensitive;
 505         cli->case_sensitive = case_sensitive;
 506         return ret;
 507 }
 508
 509 /****************************************************************************
 510 Send a keepalive packet to the server
 511 ****************************************************************************/
 512
 513 BOOL cli_send_keepalive(struct cli_state *cli)
 514 {
 515         if (cli->fd == -1) {
 516                 DEBUG(3, ("cli_send_keepalive: fd == -1\n"));
 517                 return False;
 518         }
 519         if (!send_keepalive(cli->fd)) {
 520                 close(cli->fd);
 521                 cli->fd = -1;
 522                 DEBUG(0,("Error sending keepalive packet to client.\n"));
 523                 return False;
 524         }
 525         return True;
 526 }
 527
 528 /****************************************************************************
 529  Send/receive a SMBecho command: ping the server
 530 ****************************************************************************/
 531
 532 BOOL cli_echo(struct cli_state *cli, unsigned char *data, size_t length)
 533 {
 534         char *p;
 535
 536         SMB_ASSERT(length < 1024);
 537
 538         memset(cli->outbuf,'\0',smb_size);
 539         set_message(cli->outbuf,1,length,True);
 540         SCVAL(cli->outbuf,smb_com,SMBecho);
 541         SSVAL(cli->outbuf,smb_tid,65535);
 542         SSVAL(cli->outbuf,smb_vwv0,1);
 543         cli_setup_packet(cli);
 544         p = smb_buf(cli->outbuf);
 545         memcpy(p, data, length);
 546         p += length;
 547
 548         cli_setup_bcc(cli, p);
 549
 550         cli_send_smb(cli);
 551         if (!cli_receive_smb(cli)) {
 552                 return False;
 553         }
 554
 555         if (cli_is_error(cli)) {
 556                 return False;
 557         }
 558         return True;
 559 }