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