source3/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         BOOL enc_on = cli_encryption_on(cli);
 171
 172         /* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
 173         if (cli->fd == -1) {
 174                 return False;
 175         }
 176
 177         cli_calculate_sign_mac(cli);
 178
 179         if (enc_on) {
 180                 NTSTATUS status = cli_encrypt_message(cli, &buf_out);
 181                 if (!NT_STATUS_IS_OK(status)) {
 182                         close(cli->fd);
 183                         cli->fd = -1;
 184                         cli->smb_rw_error = WRITE_ERROR;
 185                         DEBUG(0,("Error in encrypting client message. Error %s\n",
 186                                 nt_errstr(status) ));
 187                         return False;
 188                 }
 189         }
 190
 191         len = smb_len(buf_out) + 4;
 192
 193         while (nwritten < len) {
 194                 ret = write_socket(cli->fd,buf_out+nwritten,len - nwritten);
 195                 if (ret <= 0) {
 196                         if (enc_on) {
 197                                 cli_free_enc_buffer(cli, buf_out);
 198                         }
 199                         close(cli->fd);
 200                         cli->fd = -1;
 201                         cli->smb_rw_error = WRITE_ERROR;
 202                         DEBUG(0,("Error writing %d bytes to client. %d (%s)\n",
 203                                 (int)len,(int)ret, strerror(errno) ));
 204                         return False;
 205                 }
 206                 nwritten += ret;
 207         }
 208
 209         cli_free_enc_buffer(cli, buf_out);
 210
 211         /* Increment the mid so we can tell between responses. */
 212         cli->mid++;
 213         if (!cli->mid) {
 214                 cli->mid++;
 215         }
 216         return True;
 217 }
 218
 219 /****************************************************************************
 220  Setup basics in a outgoing packet.
 221 ****************************************************************************/
 222
 223 void cli_setup_packet(struct cli_state *cli)
 224 {
 225         cli->rap_error = 0;
 226         SSVAL(cli->outbuf,smb_pid,cli->pid);
 227         SSVAL(cli->outbuf,smb_uid,cli->vuid);
 228         SSVAL(cli->outbuf,smb_mid,cli->mid);
 229         if (cli->protocol > PROTOCOL_CORE) {
 230                 uint16 flags2;
 231                 if (cli->case_sensitive) {
 232                         SCVAL(cli->outbuf,smb_flg,0x0);
 233                 } else {
 234                         /* Default setting, case insensitive. */
 235                         SCVAL(cli->outbuf,smb_flg,0x8);
 236                 }
 237                 flags2 = FLAGS2_LONG_PATH_COMPONENTS;
 238                 if (cli->capabilities & CAP_UNICODE)
 239                         flags2 |= FLAGS2_UNICODE_STRINGS;
 240                 if ((cli->capabilities & CAP_DFS) && cli->dfsroot)
 241                         flags2 |= FLAGS2_DFS_PATHNAMES;
 242                 if (cli->capabilities & CAP_STATUS32)
 243                         flags2 |= FLAGS2_32_BIT_ERROR_CODES;
 244                 if (cli->use_spnego)
 245                         flags2 |= FLAGS2_EXTENDED_SECURITY;
 246                 SSVAL(cli->outbuf,smb_flg2, flags2);
 247         }
 248 }
 249
 250 /****************************************************************************
 251  Setup the bcc length of the packet from a pointer to the end of the data.
 252 ****************************************************************************/
 253
 254 void cli_setup_bcc(struct cli_state *cli, void *p)
 255 {
 256         set_message_bcc(cli->outbuf, PTR_DIFF(p, smb_buf(cli->outbuf)));
 257 }
 258
 259 /****************************************************************************
 260  Initialise credentials of a client structure.
 261 ****************************************************************************/
 262
 263 void cli_init_creds(struct cli_state *cli, const char *username, const char *domain, const char *password)
 264 {
 265         fstrcpy(cli->domain, domain);
 266         fstrcpy(cli->user_name, username);
 267         pwd_set_cleartext(&cli->pwd, password);
 268         if (!*username) {
 269                 cli->pwd.null_pwd = True;
 270         }
 271
 272         DEBUG(10,("cli_init_creds: user %s domain %s\n", cli->user_name, cli->domain));
 273 }
 274
 275 /****************************************************************************
 276  Set the signing state (used from the command line).
 277 ****************************************************************************/
 278
 279 void cli_setup_signing_state(struct cli_state *cli, int signing_state)
 280 {
 281         if (signing_state == Undefined)
 282                 return;
 283
 284         if (signing_state == False) {
 285                 cli->sign_info.allow_smb_signing = False;
 286                 cli->sign_info.mandatory_signing = False;
 287                 return;
 288         }
 289
 290         cli->sign_info.allow_smb_signing = True;
 291
 292         if (signing_state == Required)
 293                 cli->sign_info.mandatory_signing = True;
 294 }
 295
 296 /****************************************************************************
 297  Initialise a client structure. Always returns a malloc'ed struct.
 298 ****************************************************************************/
 299
 300 struct cli_state *cli_initialise(void)
 301 {
 302         struct cli_state *cli = NULL;
 303
 304         /* Check the effective uid - make sure we are not setuid */
 305         if (is_setuid_root()) {
 306                 DEBUG(0,("libsmb based programs must *NOT* be setuid root.\n"));
 307                 return NULL;
 308         }
 309
 310         cli = SMB_MALLOC_P(struct cli_state);
 311         if (!cli) {
 312                 return NULL;
 313         }
 314
 315         ZERO_STRUCTP(cli);
 316
 317         cli->port = 0;
 318         cli->fd = -1;
 319         cli->cnum = -1;
 320         cli->pid = (uint16)sys_getpid();
 321         cli->mid = 1;
 322         cli->vuid = UID_FIELD_INVALID;
 323         cli->protocol = PROTOCOL_NT1;
 324         cli->timeout = 20000; /* Timeout is in milliseconds. */
 325         cli->bufsize = CLI_BUFFER_SIZE+4;
 326         cli->max_xmit = cli->bufsize;
 327         cli->outbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
 328         cli->inbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
 329         cli->oplock_handler = cli_oplock_ack;
 330         cli->case_sensitive = False;
 331         cli->smb_rw_error = 0;
 332
 333         cli->use_spnego = lp_client_use_spnego();
 334
 335         cli->capabilities = CAP_UNICODE | CAP_STATUS32 | CAP_DFS;
 336
 337         /* Set the CLI_FORCE_DOSERR environment variable to test
 338            client routines using DOS errors instead of STATUS32
 339            ones.  This intended only as a temporary hack. */
 340         if (getenv("CLI_FORCE_DOSERR"))
 341                 cli->force_dos_errors = True;
 342
 343         if (lp_client_signing())
 344                 cli->sign_info.allow_smb_signing = True;
 345
 346         if (lp_client_signing() == Required)
 347                 cli->sign_info.mandatory_signing = True;
 348
 349         if (!cli->outbuf || !cli->inbuf)
 350                 goto error;
 351
 352         if ((cli->mem_ctx = talloc_init("cli based talloc")) == NULL)
 353                 goto error;
 354
 355         memset(cli->outbuf, 0, cli->bufsize);
 356         memset(cli->inbuf, 0, cli->bufsize);
 357
 358
 359 #if defined(DEVELOPER)
 360         /* just because we over-allocate, doesn't mean it's right to use it */
 361         clobber_region(FUNCTION_MACRO, __LINE__, cli->outbuf+cli->bufsize, SAFETY_MARGIN);
 362         clobber_region(FUNCTION_MACRO, __LINE__, cli->inbuf+cli->bufsize, SAFETY_MARGIN);
 363 #endif
 364
 365         /* initialise signing */
 366         cli_null_set_signing(cli);
 367
 368         cli->initialised = 1;
 369
 370         return cli;
 371
 372         /* Clean up after malloc() error */
 373
 374  error:
 375
 376         SAFE_FREE(cli->inbuf);
 377         SAFE_FREE(cli->outbuf);
 378         SAFE_FREE(cli);
 379         return NULL;
 380 }
 381
 382 /****************************************************************************
 383  External interface.
 384  Close an open named pipe over SMB. Free any authentication data.
 385  Returns False if the cli_close call failed.
 386  ****************************************************************************/
 387
 388 BOOL cli_rpc_pipe_close(struct rpc_pipe_client *cli)
 389 {
 390         BOOL ret;
 391
 392         if (!cli) {
 393                 return False;
 394         }
 395
 396         ret = cli_close(cli->cli, cli->fnum);
 397
 398         if (!ret) {
 399                 DEBUG(1,("cli_rpc_pipe_close: cli_close failed on pipe %s, "
 400                          "fnum 0x%x "
 401                          "to machine %s.  Error was %s\n",
 402                          cli->pipe_name,
 403                          (int) cli->fnum,
 404                          cli->cli->desthost,
 405                          cli_errstr(cli->cli)));
 406         }
 407
 408         if (cli->auth.cli_auth_data_free_func) {
 409                 (*cli->auth.cli_auth_data_free_func)(&cli->auth);
 410         }
 411
 412         DEBUG(10,("cli_rpc_pipe_close: closed pipe %s to machine %s\n",
 413                 cli->pipe_name, cli->cli->desthost ));
 414
 415         DLIST_REMOVE(cli->cli->pipe_list, cli);
 416         talloc_destroy(cli->mem_ctx);
 417         return ret;
 418 }
 419
 420 /****************************************************************************
 421  Close all pipes open on this session.
 422 ****************************************************************************/
 423
 424 void cli_nt_pipes_close(struct cli_state *cli)
 425 {
 426         struct rpc_pipe_client *cp, *next;
 427
 428         for (cp = cli->pipe_list; cp; cp = next) {
 429                 next = cp->next;
 430                 cli_rpc_pipe_close(cp);
 431         }
 432 }
 433
 434 /****************************************************************************
 435  Shutdown a client structure.
 436 ****************************************************************************/
 437
 438 void cli_shutdown(struct cli_state *cli)
 439 {
 440         cli_nt_pipes_close(cli);
 441
 442         /*
 443          * tell our peer to free his resources.  Wihtout this, when an
 444          * application attempts to do a graceful shutdown and calls
 445          * smbc_free_context() to clean up all connections, some connections
 446          * can remain active on the peer end, until some (long) timeout period
 447          * later.  This tree disconnect forces the peer to clean up, since the
 448          * connection will be going away.
 449          *
 450          * Also, do not do tree disconnect when cli->smb_rw_error is DO_NOT_DO_TDIS
 451          * the only user for this so far is smbmount which passes opened connection
 452          * down to kernel's smbfs module.
 453          */
 454         if ( (cli->cnum != (uint16)-1) && (cli->smb_rw_error != DO_NOT_DO_TDIS ) ) {
 455                 cli_tdis(cli);
 456         }
 457
 458         SAFE_FREE(cli->outbuf);
 459         SAFE_FREE(cli->inbuf);
 460
 461         cli_free_signing_context(cli);
 462         cli_free_encryption_context(cli);
 463
 464         data_blob_free(&cli->secblob);
 465         data_blob_free(&cli->user_session_key);
 466
 467         if (cli->mem_ctx) {
 468                 talloc_destroy(cli->mem_ctx);
 469                 cli->mem_ctx = NULL;
 470         }
 471
 472         if (cli->fd != -1) {
 473                 close(cli->fd);
 474         }
 475         cli->fd = -1;
 476         cli->smb_rw_error = 0;
 477
 478         SAFE_FREE(cli);
 479 }
 480
 481 /****************************************************************************
 482  Set socket options on a open connection.
 483 ****************************************************************************/
 484
 485 void cli_sockopt(struct cli_state *cli, const char *options)
 486 {
 487         set_socket_options(cli->fd, options);
 488 }
 489
 490 /****************************************************************************
 491  Set the PID to use for smb messages. Return the old pid.
 492 ****************************************************************************/
 493
 494 uint16 cli_setpid(struct cli_state *cli, uint16 pid)
 495 {
 496         uint16 ret = cli->pid;
 497         cli->pid = pid;
 498         return ret;
 499 }
 500
 501 /****************************************************************************
 502  Set the case sensitivity flag on the packets. Returns old state.
 503 ****************************************************************************/
 504
 505 BOOL cli_set_case_sensitive(struct cli_state *cli, BOOL case_sensitive)
 506 {
 507         BOOL ret = cli->case_sensitive;
 508         cli->case_sensitive = case_sensitive;
 509         return ret;
 510 }
 511
 512 /****************************************************************************
 513 Send a keepalive packet to the server
 514 ****************************************************************************/
 515
 516 BOOL cli_send_keepalive(struct cli_state *cli)
 517 {
 518         if (cli->fd == -1) {
 519                 DEBUG(3, ("cli_send_keepalive: fd == -1\n"));
 520                 return False;
 521         }
 522         if (!send_keepalive(cli->fd)) {
 523                 close(cli->fd);
 524                 cli->fd = -1;
 525                 DEBUG(0,("Error sending keepalive packet to client.\n"));
 526                 return False;
 527         }
 528         return True;
 529 }
 530
 531 /****************************************************************************
 532  Send/receive a SMBecho command: ping the server
 533 ****************************************************************************/
 534
 535 BOOL cli_echo(struct cli_state *cli, unsigned char *data, size_t length)
 536 {
 537         char *p;
 538
 539         SMB_ASSERT(length < 1024);
 540
 541         memset(cli->outbuf,'\0',smb_size);
 542         set_message(cli->outbuf,1,length,True);
 543         SCVAL(cli->outbuf,smb_com,SMBecho);
 544         SSVAL(cli->outbuf,smb_tid,65535);
 545         SSVAL(cli->outbuf,smb_vwv0,1);
 546         cli_setup_packet(cli);
 547         p = smb_buf(cli->outbuf);
 548         memcpy(p, data, length);
 549         p += length;
 550
 551         cli_setup_bcc(cli, p);
 552
 553         cli_send_smb(cli);
 554         if (!cli_receive_smb(cli)) {
 555                 return False;
 556         }
 557
 558         if (cli_is_error(cli)) {
 559                 return False;
 560         }
 561         return True;
 562 }