source3/smbd/service.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    service (connection) opening and closing
   5    Copyright (C) Andrew Tridgell 1992-1998
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 extern int DEBUGLEVEL;
  25
  26 extern struct timeval smb_last_time;
  27 extern int case_default;
  28 extern BOOL case_preserve;
  29 extern BOOL short_case_preserve;
  30 extern BOOL case_mangle;
  31 extern BOOL case_sensitive;
  32 extern BOOL use_mangled_map;
  33 extern fstring remote_machine;
  34 extern userdom_struct current_user_info;
  35 extern fstring remote_machine;
  36
  37
  38 /****************************************************************************
  39 load parameters specific to a connection/service
  40 ****************************************************************************/
  41 BOOL become_service(connection_struct *conn,BOOL do_chdir)
  42 {
  43         extern char magic_char;
  44         static connection_struct *last_conn;
  45         int snum;
  46
  47         if (!conn)  {
  48                 last_conn = NULL;
  49                 return(False);
  50         }
  51
  52         conn->lastused = smb_last_time.tv_sec;
  53
  54         snum = SNUM(conn);
  55
  56         if (do_chdir &&
  57             vfs_ChDir(conn,conn->connectpath) != 0 &&
  58             vfs_ChDir(conn,conn->origpath) != 0) {
  59                 DEBUG(0,("chdir (%s) failed\n",
  60                          conn->connectpath));
  61                 return(False);
  62         }
  63
  64         if (conn == last_conn)
  65                 return(True);
  66
  67         last_conn = conn;
  68
  69         case_default = lp_defaultcase(snum);
  70         case_preserve = lp_preservecase(snum);
  71         short_case_preserve = lp_shortpreservecase(snum);
  72         case_mangle = lp_casemangle(snum);
  73         case_sensitive = lp_casesensitive(snum);
  74         magic_char = lp_magicchar(snum);
  75         use_mangled_map = (*lp_mangled_map(snum) ? True:False);
  76         return(True);
  77 }
  78
  79 /****************************************************************************
  80  Add a home service. Returns the new service number or -1 if fail.
  81 ****************************************************************************/
  82
  83 int add_home_service(char *service, char *homedir)
  84 {
  85         int iHomeService;
  86         int iService;
  87         fstring new_service;
  88         char *usr_p = NULL;
  89
  90         if (!service || !homedir)
  91                 return -1;
  92
  93         if ((iHomeService = lp_servicenumber(HOMES_NAME)) < 0)
  94                 return -1;
  95
  96         /*
  97          * If this is a winbindd provided username, remove
  98          * the domain component before adding the service.
  99          * Log a warning if the "path=" parameter does not
 100          * include any macros.
 101          */
 102
 103         fstrcpy(new_service, service);
 104
 105         if ((usr_p = strchr(service,*lp_winbind_separator())) != NULL)
 106                 fstrcpy(new_service, usr_p+1);
 107
 108         lp_add_home(new_service,iHomeService,homedir);
 109         iService = lp_servicenumber(new_service);
 110
 111         return iService;
 112 }
 113
 114 /****************************************************************************
 115  Find a service entry. service is always in dos codepage.
 116 ****************************************************************************/
 117
 118 int find_service(char *service)
 119 {
 120    int iService;
 121
 122    all_string_sub(service,"\\","/",0);
 123
 124    iService = lp_servicenumber(service);
 125
 126    /* now handle the special case of a home directory */
 127    if (iService < 0)
 128    {
 129       char *phome_dir = get_user_home_dir(service);
 130
 131       if(!phome_dir)
 132       {
 133         /*
 134          * Try mapping the servicename, it may
 135          * be a Windows to unix mapped user name.
 136          */
 137         if(map_username(service))
 138           phome_dir = get_user_home_dir(service);
 139       }
 140
 141       DEBUG(3,("checking for home directory %s gave %s\n",service,
 142             phome_dir?phome_dir:"(NULL)"));
 143
 144       iService = add_home_service(service,phome_dir);
 145    }
 146
 147    /* If we still don't have a service, attempt to add it as a printer. */
 148    if (iService < 0)
 149    {
 150       int iPrinterService;
 151
 152       if ((iPrinterService = lp_servicenumber(PRINTERS_NAME)) >= 0)
 153       {
 154          char *pszTemp;
 155
 156          DEBUG(3,("checking whether %s is a valid printer name...\n", service));
 157          pszTemp = PRINTCAP;
 158          if ((pszTemp != NULL) && pcap_printername_ok(service, pszTemp))
 159          {
 160             DEBUG(3,("%s is a valid printer name\n", service));
 161             DEBUG(3,("adding %s as a printer service\n", service));
 162             lp_add_printer(service,iPrinterService);
 163             iService = lp_servicenumber(service);
 164             if (iService < 0)
 165                DEBUG(0,("failed to add %s as a printer service!\n", service));
 166          }
 167          else
 168             DEBUG(3,("%s is not a valid printer name\n", service));
 169       }
 170    }
 171
 172    /* Check for default vfs service?  Unsure whether to implement this */
 173    if (iService < 0)
 174    {
 175    }
 176
 177    /* just possibly it's a default service? */
 178    if (iService < 0)
 179    {
 180      char *pdefservice = lp_defaultservice();
 181      if (pdefservice && *pdefservice &&
 182          !strequal(pdefservice,service) &&
 183          !strstr(service,".."))
 184      {
 185        /*
 186         * We need to do a local copy here as lp_defaultservice()
 187         * returns one of the rotating lp_string buffers that
 188         * could get overwritten by the recursive find_service() call
 189         * below. Fix from Josef Hinteregger <joehtg@joehtg.co.at>.
 190         */
 191        pstring defservice;
 192        pstrcpy(defservice, pdefservice);
 193        iService = find_service(defservice);
 194        if (iService >= 0)
 195        {
 196          all_string_sub(service,"_","/",0);
 197          iService = lp_add_service(service,iService);
 198        }
 199      }
 200    }
 201
 202    if (iService >= 0)
 203      if (!VALID_SNUM(iService))
 204      {
 205        DEBUG(0,("Invalid snum %d for %s\n",iService,service));
 206        iService = -1;
 207      }
 208
 209    if (iService < 0)
 210      DEBUG(3,("find_service() failed to find service %s\n", service));
 211
 212    return (iService);
 213 }
 214
 215
 216 /****************************************************************************
 217   make a connection to a service
 218 ****************************************************************************/
 219 connection_struct *make_connection(char *service,char *user,char *password, int pwlen, char *dev,uint16 vuid, int *ecode)
 220 {
 221         int snum;
 222         struct passwd *pass = NULL;
 223         BOOL guest = False;
 224         BOOL force = False;
 225         connection_struct *conn;
 226         int ret;
 227
 228         strlower(service);
 229
 230         snum = find_service(service);
 231         if (snum < 0) {
 232                 if (strequal(service,"IPC$") || strequal(service,"ADMIN$")) {
 233                         DEBUG(3,("refusing IPC connection\n"));
 234                         *ecode = ERRnoipc;
 235                         return NULL;
 236                 }
 237
 238                 DEBUG(0,("%s (%s) couldn't find service %s\n",
 239                          remote_machine, client_addr(), service));
 240                 *ecode = ERRnosuchshare;
 241                 return NULL;
 242         }
 243
 244         if (strequal(service,HOMES_NAME)) {
 245                 if (*user && Get_Pwnam(user,True)) {
 246                         fstring dos_username;
 247                         fstrcpy(dos_username, user);
 248                         unix_to_dos(dos_username, True);
 249                         return(make_connection(dos_username,user,password,
 250                                                pwlen,dev,vuid,ecode));
 251                 }
 252
 253                 if(lp_security() != SEC_SHARE) {
 254                         if (validated_username(vuid)) {
 255                                 fstring dos_username;
 256                                 fstrcpy(user,validated_username(vuid));
 257                                 fstrcpy(dos_username, user);
 258                                 unix_to_dos(dos_username, True);
 259                                 return(make_connection(dos_username,user,password,pwlen,dev,vuid,ecode));
 260                         }
 261                 } else {
 262                         /* Security = share. Try with current_user_info.smb_name
 263                          * as the username.  */
 264                         if(*current_user_info.smb_name) {
 265                                 fstring dos_username;
 266                                 fstrcpy(user,current_user_info.smb_name);
 267                                 fstrcpy(dos_username, user);
 268                                 unix_to_dos(dos_username, True);
 269                                 return(make_connection(dos_username,user,password,pwlen,dev,vuid,ecode));
 270                         }
 271                 }
 272         }
 273
 274         if (!lp_snum_ok(snum) ||
 275             !check_access(smbd_server_fd(),
 276                           lp_hostsallow(snum), lp_hostsdeny(snum))) {
 277                 *ecode = ERRaccess;
 278                 return NULL;
 279         }
 280
 281         /* you can only connect to the IPC$ service as an ipc device */
 282         if (strequal(service,"IPC$") || strequal(service,"ADMIN$"))
 283                 pstrcpy(dev,"IPC");
 284
 285         if (*dev == '?' || !*dev) {
 286                 if (lp_print_ok(snum)) {
 287                         pstrcpy(dev,"LPT1:");
 288                 } else {
 289                         pstrcpy(dev,"A:");
 290                 }
 291         }
 292
 293         /* if the request is as a printer and you can't print then refuse */
 294         strupper(dev);
 295         if (!lp_print_ok(snum) && (strncmp(dev,"LPT",3) == 0)) {
 296                 DEBUG(1,("Attempt to connect to non-printer as a printer\n"));
 297                 *ecode = ERRinvdevice;
 298                 return NULL;
 299         }
 300
 301         /* Behave as a printer if we are supposed to */
 302         if (lp_print_ok(snum) && (strcmp(dev, "A:") == 0)) {
 303                 pstrcpy(dev, "LPT1:");
 304         }
 305
 306         /* lowercase the user name */
 307         strlower(user);
 308
 309         /* add it as a possible user name if we
 310            are in share mode security */
 311         if (lp_security() == SEC_SHARE) {
 312                 add_session_user(service);
 313         }
 314
 315         /* shall we let them in? */
 316         if (!authorise_login(snum,user,password,pwlen,&guest,&force,vuid)) {
 317                 DEBUG( 2, ( "Invalid username/password for %s [%s]\n", service, user ) );
 318                 *ecode = ERRbadpw;
 319                 return NULL;
 320         }
 321
 322         conn = conn_new();
 323         if (!conn) {
 324                 DEBUG(0,("Couldn't find free connection.\n"));
 325                 *ecode = ERRnoresource;
 326                 return NULL;
 327         }
 328
 329         /* find out some info about the user */
 330         pass = smb_getpwnam(user,True);
 331
 332         if (pass == NULL) {
 333                 DEBUG(0,( "Couldn't find account %s\n",user));
 334                 *ecode = ERRbaduid;
 335                 conn_free(conn);
 336                 return NULL;
 337         }
 338
 339         conn->read_only = lp_readonly(snum);
 340
 341
 342         {
 343                 pstring list;
 344                 StrnCpy(list,lp_readlist(snum),sizeof(pstring)-1);
 345                 pstring_sub(list,"%S",service);
 346
 347                 if (user_in_list(user,list))
 348                         conn->read_only = True;
 349
 350                 StrnCpy(list,lp_writelist(snum),sizeof(pstring)-1);
 351                 pstring_sub(list,"%S",service);
 352
 353                 if (user_in_list(user,list))
 354                         conn->read_only = False;
 355         }
 356
 357         /* admin user check */
 358
 359         /* JRA - original code denied admin user if the share was
 360            marked read_only. Changed as I don't think this is needed,
 361            but old code left in case there is a problem here.
 362         */
 363         if (user_in_list(user,lp_admin_users(snum))
 364 #if 0
 365             && !conn->read_only
 366 #endif
 367             ) {
 368                 conn->admin_user = True;
 369                 DEBUG(0,("%s logged in as admin user (root privileges)\n",user));
 370         } else {
 371                 conn->admin_user = False;
 372         }
 373
 374         conn->force_user = force;
 375         conn->vuid = vuid;
 376         conn->uid = pass->pw_uid;
 377         conn->gid = pass->pw_gid;
 378         safe_strcpy(conn->client_address, client_addr(), sizeof(conn->client_address)-1);
 379         conn->num_files_open = 0;
 380         conn->lastused = time(NULL);
 381         conn->service = snum;
 382         conn->used = True;
 383         conn->printer = (strncmp(dev,"LPT",3) == 0);
 384         conn->ipc = ((strncmp(dev,"IPC",3) == 0) || strequal(dev,"ADMIN$"));
 385         conn->dirptr = NULL;
 386         conn->veto_list = NULL;
 387         conn->hide_list = NULL;
 388         conn->veto_oplock_list = NULL;
 389         string_set(&conn->dirpath,"");
 390         string_set(&conn->user,user);
 391         conn->nt_user_token = NULL;
 392
 393         /*
 394          * If force user is true, then store the
 395          * given userid and also the primary groupid
 396          * of the user we're forcing.
 397          */
 398
 399         if (*lp_force_user(snum)) {
 400                 struct passwd *pass2;
 401                 pstring fuser;
 402                 pstrcpy(fuser,lp_force_user(snum));
 403
 404                 /* Allow %S to be used by force user. */
 405                 pstring_sub(fuser,"%S",service);
 406
 407                 pass2 = (struct passwd *)Get_Pwnam(fuser,True);
 408                 if (pass2) {
 409                         conn->uid = pass2->pw_uid;
 410                         conn->gid = pass2->pw_gid;
 411                         string_set(&conn->user,fuser);
 412                         fstrcpy(user,fuser);
 413                         conn->force_user = True;
 414                         DEBUG(3,("Forced user %s\n",fuser));
 415                 } else {
 416                         DEBUG(1,("Couldn't find user %s\n",fuser));
 417                 }
 418         }
 419
 420         /* admin users always run as uid=0 */
 421         if (conn->admin_user) {
 422                 conn->uid = 0;
 423         }
 424
 425 #ifdef HAVE_GETGRNAM
 426         /*
 427          * If force group is true, then override
 428          * any groupid stored for the connecting user.
 429          */
 430
 431         if (*lp_force_group(snum)) {
 432                 gid_t gid;
 433                 pstring gname;
 434                 pstring tmp_gname;
 435                 BOOL user_must_be_member = False;
 436
 437                 StrnCpy(tmp_gname,lp_force_group(snum),sizeof(pstring)-1);
 438
 439                 if (tmp_gname[0] == '+') {
 440                         user_must_be_member = True;
 441                         StrnCpy(gname,&tmp_gname[1],sizeof(pstring)-2);
 442                 } else {
 443                         StrnCpy(gname,tmp_gname,sizeof(pstring)-1);
 444                 }
 445                 /* default service may be a group name          */
 446                 pstring_sub(gname,"%S",service);
 447                 gid = nametogid(gname);
 448
 449                 if (gid != (gid_t)-1) {
 450                         /*
 451                          * If the user has been forced and the forced group starts
 452                          * with a '+', then we only set the group to be the forced
 453                          * group if the forced user is a member of that group.
 454                          * Otherwise, the meaning of the '+' would be ignored.
 455                          */
 456                         if (conn->force_user && user_must_be_member) {
 457                                 if (user_in_group_list( user, gname )) {
 458                                                 conn->gid = gid;
 459                                                 DEBUG(3,("Forced group %s for member %s\n",gname,user));
 460                                 }
 461                         } else {
 462                                 conn->gid = gid;
 463                                 DEBUG(3,("Forced group %s\n",gname));
 464                         }
 465                 } else {
 466                         DEBUG(1,("Couldn't find group %s\n",gname));
 467                 }
 468         }
 469 #endif /* HAVE_GETGRNAM */
 470
 471         {
 472                 pstring s;
 473                 pstrcpy(s,lp_pathname(snum));
 474                 standard_sub_conn(conn,s);
 475                 string_set(&conn->connectpath,s);
 476                 DEBUG(3,("Connect path is %s\n",s));
 477         }
 478
 479         /* groups stuff added by ih */
 480         conn->ngroups = 0;
 481         conn->groups = NULL;
 482
 483         /* Find all the groups this uid is in and
 484            store them. Used by become_user() */
 485         initialise_groups(conn->user, conn->uid, conn->gid);
 486         get_current_groups(&conn->ngroups,&conn->groups);
 487
 488         /* check number of connections */
 489         if (!claim_connection(conn,
 490                               lp_servicename(SNUM(conn)),
 491                               lp_max_connections(SNUM(conn)),
 492                               False)) {
 493                 DEBUG(1,("too many connections - rejected\n"));
 494                 *ecode = ERRnoresource;
 495                 conn_free(conn);
 496                 return NULL;
 497         }
 498
 499         conn->nt_user_token = create_nt_token(conn->uid, conn->gid,
 500                                               conn->ngroups, conn->groups,
 501                                               guest);
 502
 503         /*
 504          * New code to check if there's a share security descripter
 505          * added from NT server manager. This is done after the
 506          * smb.conf checks are done as we need a uid and token. JRA.
 507          */
 508
 509         {
 510                 BOOL can_write = share_access_check(conn, snum, vuid, FILE_WRITE_DATA);
 511
 512                 if (!can_write) {
 513                         if (!share_access_check(conn, snum, vuid, FILE_READ_DATA)) {
 514                                 /* No access, read or write. */
 515                                 *ecode = ERRaccess;
 516                                 DEBUG(0,( "make_connection: connection to %s denied due to security descriptor.\n",
 517                                         service ));
 518                                 conn_free(conn);
 519                                 return NULL;
 520                         } else {
 521                                 conn->read_only = True;
 522                         }
 523                 }
 524         }
 525         /* Initialise VFS function pointers */
 526
 527         if (*lp_vfsobj(SNUM(conn))) {
 528
 529 #ifdef HAVE_LIBDL
 530
 531             /* Loadable object file */
 532
 533             if (!vfs_init_custom(conn)) {
 534                 DEBUG(0, ("vfs_init failed\n"));
 535                     conn_free(conn);
 536                         return NULL;
 537             }
 538 #else
 539             DEBUG(0, ("No libdl present - cannot use VFS objects\n"));
 540             conn_free(conn);
 541             return NULL;
 542 #endif
 543
 544         } else {
 545
 546             /* Normal share - initialise with disk access functions */
 547
 548             vfs_init_default(conn);
 549         }
 550
 551         /* execute any "root preexec = " line */
 552         if (*lp_rootpreexec(SNUM(conn))) {
 553                 pstring cmd;
 554                 pstrcpy(cmd,lp_rootpreexec(SNUM(conn)));
 555                 standard_sub_conn(conn,cmd);
 556                 DEBUG(5,("cmd=%s\n",cmd));
 557                 ret = smbrun(cmd,NULL);
 558                 if (ret != 0 && lp_rootpreexec_close(SNUM(conn))) {
 559                         DEBUG(1,("preexec gave %d - failing connection\n", ret));
 560                         conn_free(conn);
 561                         *ecode = ERRsrverror;
 562                         return NULL;
 563                 }
 564         }
 565
 566         if (!become_user(conn, conn->vuid)) {
 567                 DEBUG(0,("Can't become connected user!\n"));
 568                 yield_connection(conn,
 569                                  lp_servicename(SNUM(conn)),
 570                                  lp_max_connections(SNUM(conn)));
 571                 conn_free(conn);
 572                 *ecode = ERRbadpw;
 573                 return NULL;
 574         }
 575
 576         if (vfs_ChDir(conn,conn->connectpath) != 0) {
 577                 DEBUG(0,("%s (%s) Can't change directory to %s (%s)\n",
 578                          remote_machine, conn->client_address,
 579                          conn->connectpath,strerror(errno)));
 580                 unbecome_user();
 581                 yield_connection(conn,
 582                                  lp_servicename(SNUM(conn)),
 583                                  lp_max_connections(SNUM(conn)));
 584                 conn_free(conn);
 585                 *ecode = ERRnosuchshare;
 586                 return NULL;
 587         }
 588
 589         string_set(&conn->origpath,conn->connectpath);
 590
 591 #if SOFTLINK_OPTIMISATION
 592         /* resolve any soft links early */
 593         {
 594                 pstring s;
 595                 pstrcpy(s,conn->connectpath);
 596                 vfs_GetWd(conn,s);
 597                 string_set(&conn->connectpath,s);
 598                 vfs_ChDir(conn,conn->connectpath);
 599         }
 600 #endif
 601
 602         add_session_user(user);
 603
 604         /* execute any "preexec = " line */
 605         if (*lp_preexec(SNUM(conn))) {
 606                 pstring cmd;
 607                 pstrcpy(cmd,lp_preexec(SNUM(conn)));
 608                 standard_sub_conn(conn,cmd);
 609                 ret = smbrun(cmd,NULL);
 610                 if (ret != 0 && lp_preexec_close(SNUM(conn))) {
 611                         DEBUG(1,("preexec gave %d - failing connection\n", ret));
 612                         conn_free(conn);
 613                         *ecode = ERRsrverror;
 614                         return NULL;
 615                 }
 616         }
 617
 618         /*
 619          * Print out the 'connected as' stuff here as we need
 620          * to know the effective uid and gid we will be using.
 621          */
 622
 623         if( DEBUGLVL( IS_IPC(conn) ? 3 : 1 ) ) {
 624                 dbgtext( "%s (%s) ", remote_machine, conn->client_address );
 625                 dbgtext( "connect to service %s ", lp_servicename(SNUM(conn)) );
 626                 dbgtext( "as user %s ", user );
 627                 dbgtext( "(uid=%d, gid=%d) ", (int)geteuid(), (int)getegid() );
 628                 dbgtext( "(pid %d)\n", (int)sys_getpid() );
 629         }
 630
 631         /* we've finished with the sensitive stuff */
 632         unbecome_user();
 633
 634         /* Add veto/hide lists */
 635         if (!IS_IPC(conn) && !IS_PRINT(conn)) {
 636                 set_namearray( &conn->veto_list, lp_veto_files(SNUM(conn)));
 637                 set_namearray( &conn->hide_list, lp_hide_files(SNUM(conn)));
 638                 set_namearray( &conn->veto_oplock_list, lp_veto_oplocks(SNUM(conn)));
 639         }
 640
 641         /* Invoke VFS make connection hook */
 642
 643         if (conn->vfs_ops.connect) {
 644                 if (conn->vfs_ops.connect(conn, service, user) < 0)
 645                         return NULL;
 646         }
 647
 648         return(conn);
 649 }
 650
 651
 652 /****************************************************************************
 653 close a cnum
 654 ****************************************************************************/
 655 void close_cnum(connection_struct *conn, uint16 vuid)
 656 {
 657         DirCacheFlush(SNUM(conn));
 658
 659         unbecome_user();
 660
 661         DEBUG(IS_IPC(conn)?3:1, ("%s (%s) closed connection to service %s\n",
 662                                  remote_machine,conn->client_address,
 663                                  lp_servicename(SNUM(conn))));
 664
 665         if (conn->vfs_ops.disconnect != NULL) {
 666
 667             /* Call VFS disconnect hook */
 668
 669             conn->vfs_ops.disconnect(conn);
 670
 671         }
 672
 673         yield_connection(conn,
 674                          lp_servicename(SNUM(conn)),
 675                          lp_max_connections(SNUM(conn)));
 676
 677         file_close_conn(conn);
 678         dptr_closecnum(conn);
 679
 680         /* execute any "postexec = " line */
 681         if (*lp_postexec(SNUM(conn)) &&
 682             become_user(conn, vuid))  {
 683                 pstring cmd;
 684                 pstrcpy(cmd,lp_postexec(SNUM(conn)));
 685                 standard_sub_conn(conn,cmd);
 686                 smbrun(cmd,NULL);
 687                 unbecome_user();
 688         }
 689
 690         unbecome_user();
 691         /* execute any "root postexec = " line */
 692         if (*lp_rootpostexec(SNUM(conn)))  {
 693                 pstring cmd;
 694                 pstrcpy(cmd,lp_rootpostexec(SNUM(conn)));
 695                 standard_sub_conn(conn,cmd);
 696                 smbrun(cmd,NULL);
 697         }
 698         conn_free(conn);
 699 }