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