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         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         char *buf_out;
 168
 169         /* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
 170         if (cli->fd == -1) {
 171                 return False;
 172         }
 173
 174         cli_calculate_sign_mac(cli);
 175
 176         status = cli_encrypt_message(cli, &buf_out);
 177         if (!NT_STATUS_IS_OK(status)) {
 178                 close(cli->fd);
 179                 cli->fd = -1;
 180                 cli->smb_rw_error = WRITE_ERROR;
 181                 DEBUG(0,("Error in encrypting client message. Error %s\n",
 182                         nt_errstr(status) ));
 183                 return False;
 184         }
 185
 186         len = smb_len(buf_out) + 4;
 187
 188         while (nwritten < len) {
 189                 ret = write_socket(cli->fd,buf_out+nwritten,len - nwritten);
 190                 if (ret <= 0) {
 191                         cli_free_enc_buffer(cli, buf_out);
 192                         close(cli->fd);
 193                         cli->fd = -1;
 194                         cli->smb_rw_error = WRITE_ERROR;
 195                         DEBUG(0,("Error writing %d bytes to client. %d (%s)\n",
 196                                 (int)len,(int)ret, strerror(errno) ));
 197                         return False;
 198                 }
 199                 nwritten += ret;
 200         }
 201
 202         cli_free_enc_buffer(cli, buf_out);
 203
 204         /* Increment the mid so we can tell between responses. */
 205         cli->mid++;
 206         if (!cli->mid) {
 207                 cli->mid++;
 208         }
 209         return True;
 210 }
 211
 212 /****************************************************************************
 213  Setup basics in a outgoing packet.
 214 ****************************************************************************/
 215
 216 void cli_setup_packet(struct cli_state *cli)
 217 {
 218         cli->rap_error = 0;
 219         SSVAL(cli->outbuf,smb_pid,cli->pid);
 220         SSVAL(cli->outbuf,smb_uid,cli->vuid);
 221         SSVAL(cli->outbuf,smb_mid,cli->mid);
 222         if (cli->protocol > PROTOCOL_CORE) {
 223                 uint16 flags2;
 224                 if (cli->case_sensitive) {
 225                         SCVAL(cli->outbuf,smb_flg,0x0);
 226                 } else {
 227                         /* Default setting, case insensitive. */
 228                         SCVAL(cli->outbuf,smb_flg,0x8);
 229                 }
 230                 flags2 = FLAGS2_LONG_PATH_COMPONENTS;
 231                 if (cli->capabilities & CAP_UNICODE)
 232                         flags2 |= FLAGS2_UNICODE_STRINGS;
 233                 if ((cli->capabilities & CAP_DFS) && cli->dfsroot)
 234                         flags2 |= FLAGS2_DFS_PATHNAMES;
 235                 if (cli->capabilities & CAP_STATUS32)
 236                         flags2 |= FLAGS2_32_BIT_ERROR_CODES;
 237                 if (cli->use_spnego)
 238                         flags2 |= FLAGS2_EXTENDED_SECURITY;
 239                 SSVAL(cli->outbuf,smb_flg2, flags2);
 240         }
 241 }
 242
 243 /****************************************************************************
 244  Setup the bcc length of the packet from a pointer to the end of the data.
 245 ****************************************************************************/
 246
 247 void cli_setup_bcc(struct cli_state *cli, void *p)
 248 {
 249         set_message_bcc(cli->outbuf, PTR_DIFF(p, smb_buf(cli->outbuf)));
 250 }
 251
 252 /****************************************************************************
 253  Initialise credentials of a client structure.
 254 ****************************************************************************/
 255
 256 void cli_init_creds(struct cli_state *cli, const char *username, const char *domain, const char *password)
 257 {
 258         fstrcpy(cli->domain, domain);
 259         fstrcpy(cli->user_name, username);
 260         pwd_set_cleartext(&cli->pwd, password);
 261         if (!*username) {
 262                 cli->pwd.null_pwd = True;
 263         }
 264
 265         DEBUG(10,("cli_init_creds: user %s domain %s\n", cli->user_name, cli->domain));
 266 }
 267
 268 /****************************************************************************
 269  Set the signing state (used from the command line).
 270 ****************************************************************************/
 271
 272 void cli_setup_signing_state(struct cli_state *cli, int signing_state)
 273 {
 274         if (signing_state == Undefined)
 275                 return;
 276
 277         if (signing_state == False) {
 278                 cli->sign_info.allow_smb_signing = False;
 279                 cli->sign_info.mandatory_signing = False;
 280                 return;
 281         }
 282
 283         cli->sign_info.allow_smb_signing = True;
 284
 285         if (signing_state == Required)
 286                 cli->sign_info.mandatory_signing = True;
 287 }
 288
 289 /****************************************************************************
 290  Initialise a client structure. Always returns a malloc'ed struct.
 291 ****************************************************************************/
 292
 293 struct cli_state *cli_initialise(void)
 294 {
 295         struct cli_state *cli = NULL;
 296
 297         /* Check the effective uid - make sure we are not setuid */
 298         if (is_setuid_root()) {
 299                 DEBUG(0,("libsmb based programs must *NOT* be setuid root.\n"));
 300                 return NULL;
 301         }
 302
 303         cli = SMB_MALLOC_P(struct cli_state);
 304         if (!cli) {
 305                 return NULL;
 306         }
 307
 308         ZERO_STRUCTP(cli);
 309
 310         cli->port = 0;
 311         cli->fd = -1;
 312         cli->cnum = -1;
 313         cli->pid = (uint16)sys_getpid();
 314         cli->mid = 1;
 315         cli->vuid = UID_FIELD_INVALID;
 316         cli->protocol = PROTOCOL_NT1;
 317         cli->timeout = 20000; /* Timeout is in milliseconds. */
 318         cli->bufsize = CLI_BUFFER_SIZE+4;
 319         cli->max_xmit = cli->bufsize;
 320         cli->outbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
 321         cli->inbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
 322         cli->oplock_handler = cli_oplock_ack;
 323         cli->case_sensitive = False;
 324         cli->smb_rw_error = 0;
 325
 326         cli->use_spnego = lp_client_use_spnego();
 327
 328         cli->capabilities = CAP_UNICODE | CAP_STATUS32 | CAP_DFS;
 329
 330         /* Set the CLI_FORCE_DOSERR environment variable to test
 331            client routines using DOS errors instead of STATUS32
 332            ones.  This intended only as a temporary hack. */
 333         if (getenv("CLI_FORCE_DOSERR"))
 334                 cli->force_dos_errors = True;
 335
 336         if (lp_client_signing())
 337                 cli->sign_info.allow_smb_signing = True;
 338
 339         if (lp_client_signing() == Required)
 340                 cli->sign_info.mandatory_signing = True;
 341
 342         if (!cli->outbuf || !cli->inbuf)
 343                 goto error;
 344
 345         if ((cli->mem_ctx = talloc_init("cli based talloc")) == NULL)
 346                 goto error;
 347
 348         memset(cli->outbuf, 0, cli->bufsize);
 349         memset(cli->inbuf, 0, cli->bufsize);
 350
 351
 352 #if defined(DEVELOPER)
 353         /* just because we over-allocate, doesn't mean it's right to use it */
 354         clobber_region(FUNCTION_MACRO, __LINE__, cli->outbuf+cli->bufsize, SAFETY_MARGIN);
 355         clobber_region(FUNCTION_MACRO, __LINE__, cli->inbuf+cli->bufsize, SAFETY_MARGIN);
 356 #endif
 357
 358         /* initialise signing */
 359         cli_null_set_signing(cli);
 360
 361         cli->initialised = 1;
 362
 363         return cli;
 364
 365         /* Clean up after malloc() error */
 366
 367  error:
 368
 369         SAFE_FREE(cli->inbuf);
 370         SAFE_FREE(cli->outbuf);
 371         SAFE_FREE(cli);
 372         return NULL;
 373 }
 374
 375 /****************************************************************************
 376  External interface.
 377  Close an open named pipe over SMB. Free any authentication data.
 378  Returns False if the cli_close call failed.
 379  ****************************************************************************/
 380
 381 BOOL cli_rpc_pipe_close(struct rpc_pipe_client *cli)
 382 {
 383         BOOL ret;
 384
 385         if (!cli) {
 386                 return False;
 387         }
 388
 389         ret = cli_close(cli->cli, cli->fnum);
 390
 391         if (!ret) {
 392                 DEBUG(1,("cli_rpc_pipe_close: cli_close failed on pipe %s, "
 393                          "fnum 0x%x "
 394                          "to machine %s.  Error was %s\n",
 395                          cli->pipe_name,
 396                          (int) cli->fnum,
 397                          cli->cli->desthost,
 398                          cli_errstr(cli->cli)));
 399         }
 400
 401         if (cli->auth.cli_auth_data_free_func) {
 402                 (*cli->auth.cli_auth_data_free_func)(&cli->auth);
 403         }
 404
 405         DEBUG(10,("cli_rpc_pipe_close: closed pipe %s to machine %s\n",
 406                 cli->pipe_name, cli->cli->desthost ));
 407
 408         DLIST_REMOVE(cli->cli->pipe_list, cli);
 409         talloc_destroy(cli->mem_ctx);
 410         return ret;
 411 }
 412
 413 /****************************************************************************
 414  Close all pipes open on this session.
 415 ****************************************************************************/
 416
 417 void cli_nt_pipes_close(struct cli_state *cli)
 418 {
 419         struct rpc_pipe_client *cp, *next;
 420
 421         for (cp = cli->pipe_list; cp; cp = next) {
 422                 next = cp->next;
 423                 cli_rpc_pipe_close(cp);
 424         }
 425 }
 426
 427 /****************************************************************************
 428  Shutdown a client structure.
 429 ****************************************************************************/
 430
 431 void cli_shutdown(struct cli_state *cli)
 432 {
 433         cli_nt_pipes_close(cli);
 434
 435         /*
 436          * tell our peer to free his resources.  Wihtout this, when an
 437          * application attempts to do a graceful shutdown and calls
 438          * smbc_free_context() to clean up all connections, some connections
 439          * can remain active on the peer end, until some (long) timeout period
 440          * later.  This tree disconnect forces the peer to clean up, since the
 441          * connection will be going away.
 442          *
 443          * Also, do not do tree disconnect when cli->smb_rw_error is DO_NOT_DO_TDIS
 444          * the only user for this so far is smbmount which passes opened connection
 445          * down to kernel's smbfs module.
 446          */
 447         if ( (cli->cnum != (uint16)-1) && (cli->smb_rw_error != DO_NOT_DO_TDIS ) ) {
 448                 cli_tdis(cli);
 449         }
 450
 451         SAFE_FREE(cli->outbuf);
 452         SAFE_FREE(cli->inbuf);
 453
 454         cli_free_signing_context(cli);
 455         cli_free_encryption_context(cli);
 456
 457         data_blob_free(&cli->secblob);
 458         data_blob_free(&cli->user_session_key);
 459
 460         if (cli->mem_ctx) {
 461                 talloc_destroy(cli->mem_ctx);
 462                 cli->mem_ctx = NULL;
 463         }
 464
 465         if (cli->fd != -1) {
 466                 close(cli->fd);
 467         }
 468         cli->fd = -1;
 469         cli->smb_rw_error = 0;
 470
 471         SAFE_FREE(cli);
 472 }
 473
 474 /****************************************************************************
 475  Set socket options on a open connection.
 476 ****************************************************************************/
 477
 478 void cli_sockopt(struct cli_state *cli, const char *options)
 479 {
 480         set_socket_options(cli->fd, options);
 481 }
 482
 483 /****************************************************************************
 484  Set the PID to use for smb messages. Return the old pid.
 485 ****************************************************************************/
 486
 487 uint16 cli_setpid(struct cli_state *cli, uint16 pid)
 488 {
 489         uint16 ret = cli->pid;
 490         cli->pid = pid;
 491         return ret;
 492 }
 493
 494 /****************************************************************************
 495  Set the case sensitivity flag on the packets. Returns old state.
 496 ****************************************************************************/
 497
 498 BOOL cli_set_case_sensitive(struct cli_state *cli, BOOL case_sensitive)
 499 {
 500         BOOL ret = cli->case_sensitive;
 501         cli->case_sensitive = case_sensitive;
 502         return ret;
 503 }
 504
 505 /****************************************************************************
 506 Send a keepalive packet to the server
 507 ****************************************************************************/
 508
 509 BOOL cli_send_keepalive(struct cli_state *cli)
 510 {
 511         if (cli->fd == -1) {
 512                 DEBUG(3, ("cli_send_keepalive: fd == -1\n"));
 513                 return False;
 514         }
 515         if (!send_keepalive(cli->fd)) {
 516                 close(cli->fd);
 517                 cli->fd = -1;
 518                 DEBUG(0,("Error sending keepalive packet to client.\n"));
 519                 return False;
 520         }
 521         return True;
 522 }
 523
 524 /****************************************************************************
 525  Send/receive a SMBecho command: ping the server
 526 ****************************************************************************/
 527
 528 BOOL cli_echo(struct cli_state *cli, unsigned char *data, size_t length)
 529 {
 530         char *p;
 531
 532         SMB_ASSERT(length < 1024);
 533
 534         memset(cli->outbuf,'\0',smb_size);
 535         set_message(cli->outbuf,1,length,True);
 536         SCVAL(cli->outbuf,smb_com,SMBecho);
 537         SSVAL(cli->outbuf,smb_tid,65535);
 538         SSVAL(cli->outbuf,smb_vwv0,1);
 539         cli_setup_packet(cli);
 540         p = smb_buf(cli->outbuf);
 541         memcpy(p, data, length);
 542         p += length;
 543
 544         cli_setup_bcc(cli, p);
 545
 546         cli_send_smb(cli);
 547         if (!cli_receive_smb(cli)) {
 548                 return False;
 549         }
 550
 551         if (cli_is_error(cli)) {
 552                 return False;
 553         }
 554         return True;
 555 }