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                         return(make_connection(dos_username,user,password,
 249                                                pwlen,dev,vuid,ecode));
 250                 }
 251
 252                 if(lp_security() != SEC_SHARE) {
 253                         if (validated_username(vuid)) {
 254                                 fstring dos_username;
 255                                 fstrcpy(user,validated_username(vuid));
 256                                 fstrcpy(dos_username, user);
 257                                 return(make_connection(dos_username,user,password,pwlen,dev,vuid,ecode));
 258                         }
 259                 } else {
 260                         /* Security = share. Try with current_user_info.smb_name
 261                          * as the username.  */
 262                         if(*current_user_info.smb_name) {
 263                                 fstring dos_username;
 264                                 fstrcpy(user,current_user_info.smb_name);
 265                                 fstrcpy(dos_username, user);
 266                                 return(make_connection(dos_username,user,password,pwlen,dev,vuid,ecode));
 267                         }
 268                 }
 269         }
 270
 271         if (!lp_snum_ok(snum) ||
 272             !check_access(smbd_server_fd(),
 273                           lp_hostsallow(snum), lp_hostsdeny(snum))) {
 274                 *ecode = ERRaccess;
 275                 return NULL;
 276         }
 277
 278         /* you can only connect to the IPC$ service as an ipc device */
 279         if (strequal(service,"IPC$") || strequal(service,"ADMIN$"))
 280                 pstrcpy(dev,"IPC");
 281
 282         if (*dev == '?' || !*dev) {
 283                 if (lp_print_ok(snum)) {
 284                         pstrcpy(dev,"LPT1:");
 285                 } else {
 286                         pstrcpy(dev,"A:");
 287                 }
 288         }
 289
 290         /* if the request is as a printer and you can't print then refuse */
 291         strupper(dev);
 292         if (!lp_print_ok(snum) && (strncmp(dev,"LPT",3) == 0)) {
 293                 DEBUG(1,("Attempt to connect to non-printer as a printer\n"));
 294                 *ecode = ERRinvdevice;
 295                 return NULL;
 296         }
 297
 298         /* Behave as a printer if we are supposed to */
 299         if (lp_print_ok(snum) && (strcmp(dev, "A:") == 0)) {
 300                 pstrcpy(dev, "LPT1:");
 301         }
 302
 303         /* lowercase the user name */
 304         strlower(user);
 305
 306         /* add it as a possible user name if we
 307            are in share mode security */
 308         if (lp_security() == SEC_SHARE) {
 309                 add_session_user(service);
 310         }
 311
 312         /* shall we let them in? */
 313         if (!authorise_login(snum,user,password,pwlen,&guest,&force,vuid)) {
 314                 DEBUG( 2, ( "Invalid username/password for %s [%s]\n", service, user ) );
 315                 *ecode = ERRbadpw;
 316                 return NULL;
 317         }
 318
 319         conn = conn_new();
 320         if (!conn) {
 321                 DEBUG(0,("Couldn't find free connection.\n"));
 322                 *ecode = ERRnoresource;
 323                 return NULL;
 324         }
 325
 326         /* find out some info about the user */
 327         pass = smb_getpwnam(user,True);
 328
 329         if (pass == NULL) {
 330                 DEBUG(0,( "Couldn't find account %s\n",user));
 331                 *ecode = ERRbaduid;
 332                 conn_free(conn);
 333                 return NULL;
 334         }
 335
 336         conn->read_only = lp_readonly(snum);
 337
 338
 339         {
 340                 pstring list;
 341                 StrnCpy(list,lp_readlist(snum),sizeof(pstring)-1);
 342                 pstring_sub(list,"%S",service);
 343
 344                 if (user_in_list(user,list))
 345                         conn->read_only = True;
 346
 347                 StrnCpy(list,lp_writelist(snum),sizeof(pstring)-1);
 348                 pstring_sub(list,"%S",service);
 349
 350                 if (user_in_list(user,list))
 351                         conn->read_only = False;
 352         }
 353
 354         /* admin user check */
 355
 356         /* JRA - original code denied admin user if the share was
 357            marked read_only. Changed as I don't think this is needed,
 358            but old code left in case there is a problem here.
 359         */
 360         if (user_in_list(user,lp_admin_users(snum))
 361 #if 0
 362             && !conn->read_only
 363 #endif
 364             ) {
 365                 conn->admin_user = True;
 366                 DEBUG(0,("%s logged in as admin user (root privileges)\n",user));
 367         } else {
 368                 conn->admin_user = False;
 369         }
 370
 371         conn->force_user = force;
 372         conn->vuid = vuid;
 373         conn->uid = pass->pw_uid;
 374         conn->gid = pass->pw_gid;
 375         safe_strcpy(conn->client_address, client_addr(), sizeof(conn->client_address)-1);
 376         conn->num_files_open = 0;
 377         conn->lastused = time(NULL);
 378         conn->service = snum;
 379         conn->used = True;
 380         conn->printer = (strncmp(dev,"LPT",3) == 0);
 381         conn->ipc = ((strncmp(dev,"IPC",3) == 0) || strequal(dev,"ADMIN$"));
 382         conn->dirptr = NULL;
 383         conn->veto_list = NULL;
 384         conn->hide_list = NULL;
 385         conn->veto_oplock_list = NULL;
 386         string_set(&conn->dirpath,"");
 387         string_set(&conn->user,user);
 388         conn->nt_user_token = NULL;
 389
 390         /*
 391          * If force user is true, then store the
 392          * given userid and also the primary groupid
 393          * of the user we're forcing.
 394          */
 395
 396         if (*lp_force_user(snum)) {
 397                 struct passwd *pass2;
 398                 pstring fuser;
 399                 pstrcpy(fuser,lp_force_user(snum));
 400
 401                 /* Allow %S to be used by force user. */
 402                 pstring_sub(fuser,"%S",service);
 403
 404                 pass2 = (struct passwd *)Get_Pwnam(fuser,True);
 405                 if (pass2) {
 406                         conn->uid = pass2->pw_uid;
 407                         conn->gid = pass2->pw_gid;
 408                         string_set(&conn->user,fuser);
 409                         fstrcpy(user,fuser);
 410                         conn->force_user = True;
 411                         DEBUG(3,("Forced user %s\n",fuser));
 412                 } else {
 413                         DEBUG(1,("Couldn't find user %s\n",fuser));
 414                 }
 415         }
 416
 417         /* admin users always run as uid=0 */
 418         if (conn->admin_user) {
 419                 conn->uid = 0;
 420         }
 421
 422 #ifdef HAVE_GETGRNAM
 423         /*
 424          * If force group is true, then override
 425          * any groupid stored for the connecting user.
 426          */
 427
 428         if (*lp_force_group(snum)) {
 429                 gid_t gid;
 430                 pstring gname;
 431                 pstring tmp_gname;
 432                 BOOL user_must_be_member = False;
 433
 434                 StrnCpy(tmp_gname,lp_force_group(snum),sizeof(pstring)-1);
 435
 436                 if (tmp_gname[0] == '+') {
 437                         user_must_be_member = True;
 438                         StrnCpy(gname,&tmp_gname[1],sizeof(pstring)-2);
 439                 } else {
 440                         StrnCpy(gname,tmp_gname,sizeof(pstring)-1);
 441                 }
 442                 /* default service may be a group name          */
 443                 pstring_sub(gname,"%S",service);
 444                 gid = nametogid(gname);
 445
 446                 if (gid != (gid_t)-1) {
 447                         /*
 448                          * If the user has been forced and the forced group starts
 449                          * with a '+', then we only set the group to be the forced
 450                          * group if the forced user is a member of that group.
 451                          * Otherwise, the meaning of the '+' would be ignored.
 452                          */
 453                         if (conn->force_user && user_must_be_member) {
 454                                 if (user_in_group_list( user, gname )) {
 455                                                 conn->gid = gid;
 456                                                 DEBUG(3,("Forced group %s for member %s\n",gname,user));
 457                                 }
 458                         } else {
 459                                 conn->gid = gid;
 460                                 DEBUG(3,("Forced group %s\n",gname));
 461                         }
 462                 } else {
 463                         DEBUG(1,("Couldn't find group %s\n",gname));
 464                 }
 465         }
 466 #endif /* HAVE_GETGRNAM */
 467
 468         {
 469                 pstring s;
 470                 pstrcpy(s,lp_pathname(snum));
 471                 standard_sub_conn(conn,s);
 472                 string_set(&conn->connectpath,s);
 473                 DEBUG(3,("Connect path is %s\n",s));
 474         }
 475
 476         /* groups stuff added by ih */
 477         conn->ngroups = 0;
 478         conn->groups = NULL;
 479
 480         /* Find all the groups this uid is in and
 481            store them. Used by become_user() */
 482         initialise_groups(conn->user, conn->uid, conn->gid);
 483         get_current_groups(&conn->ngroups,&conn->groups);
 484
 485         /* check number of connections */
 486         if (!claim_connection(conn,
 487                               lp_servicename(SNUM(conn)),
 488                               lp_max_connections(SNUM(conn)),
 489                               False)) {
 490                 DEBUG(1,("too many connections - rejected\n"));
 491                 *ecode = ERRnoresource;
 492                 conn_free(conn);
 493                 return NULL;
 494         }
 495
 496         conn->nt_user_token = create_nt_token(conn->uid, conn->gid,
 497                                               conn->ngroups, conn->groups,
 498                                               guest);
 499
 500         /*
 501          * New code to check if there's a share security descripter
 502          * added from NT server manager. This is done after the
 503          * smb.conf checks are done as we need a uid and token. JRA.
 504          */
 505
 506         {
 507                 BOOL can_write = share_access_check(conn, snum, vuid, FILE_WRITE_DATA);
 508
 509                 if (!can_write) {
 510                         if (!share_access_check(conn, snum, vuid, FILE_READ_DATA)) {
 511                                 /* No access, read or write. */
 512                                 *ecode = ERRaccess;
 513                                 DEBUG(0,( "make_connection: connection to %s denied due to security descriptor.\n",
 514                                         service ));
 515                                 conn_free(conn);
 516                                 return NULL;
 517                         } else {
 518                                 conn->read_only = True;
 519                         }
 520                 }
 521         }
 522         /* Initialise VFS function pointers */
 523
 524         if (!vfs_init(conn)) {
 525                 DEBUG(0, ("vfs_init failed for service %s\n", lp_servicename(SNUM(conn))));
 526                 conn_free(conn);
 527                 return NULL;
 528         }
 529
 530         /* execute any "root preexec = " line */
 531         if (*lp_rootpreexec(SNUM(conn))) {
 532                 pstring cmd;
 533                 pstrcpy(cmd,lp_rootpreexec(SNUM(conn)));
 534                 standard_sub_conn(conn,cmd);
 535                 DEBUG(5,("cmd=%s\n",cmd));
 536                 ret = smbrun(cmd,NULL);
 537                 if (ret != 0 && lp_rootpreexec_close(SNUM(conn))) {
 538                         DEBUG(1,("preexec gave %d - failing connection\n", ret));
 539                         conn_free(conn);
 540                         *ecode = ERRsrverror;
 541                         return NULL;
 542                 }
 543         }
 544
 545         if (!become_user(conn, conn->vuid)) {
 546                 DEBUG(0,("Can't become connected user!\n"));
 547                 yield_connection(conn,
 548                                  lp_servicename(SNUM(conn)),
 549                                  lp_max_connections(SNUM(conn)));
 550                 conn_free(conn);
 551                 *ecode = ERRbadpw;
 552                 return NULL;
 553         }
 554
 555         if (vfs_ChDir(conn,conn->connectpath) != 0) {
 556                 DEBUG(0,("%s (%s) Can't change directory to %s (%s)\n",
 557                          remote_machine, conn->client_address,
 558                          conn->connectpath,strerror(errno)));
 559                 unbecome_user();
 560                 yield_connection(conn,
 561                                  lp_servicename(SNUM(conn)),
 562                                  lp_max_connections(SNUM(conn)));
 563                 conn_free(conn);
 564                 *ecode = ERRnosuchshare;
 565                 return NULL;
 566         }
 567
 568         string_set(&conn->origpath,conn->connectpath);
 569
 570 #if SOFTLINK_OPTIMISATION
 571         /* resolve any soft links early */
 572         {
 573                 pstring s;
 574                 pstrcpy(s,conn->connectpath);
 575                 vfs_GetWd(conn,s);
 576                 string_set(&conn->connectpath,s);
 577                 vfs_ChDir(conn,conn->connectpath);
 578         }
 579 #endif
 580
 581         add_session_user(user);
 582
 583         /* execute any "preexec = " line */
 584         if (*lp_preexec(SNUM(conn))) {
 585                 pstring cmd;
 586                 pstrcpy(cmd,lp_preexec(SNUM(conn)));
 587                 standard_sub_conn(conn,cmd);
 588                 ret = smbrun(cmd,NULL);
 589                 if (ret != 0 && lp_preexec_close(SNUM(conn))) {
 590                         DEBUG(1,("preexec gave %d - failing connection\n", ret));
 591                         conn_free(conn);
 592                         *ecode = ERRsrverror;
 593                         return NULL;
 594                 }
 595         }
 596
 597         /*
 598          * Print out the 'connected as' stuff here as we need
 599          * to know the effective uid and gid we will be using.
 600          */
 601
 602         if( DEBUGLVL( IS_IPC(conn) ? 3 : 1 ) ) {
 603                 dbgtext( "%s (%s) ", remote_machine, conn->client_address );
 604                 dbgtext( "connect to service %s ", lp_servicename(SNUM(conn)) );
 605                 dbgtext( "as user %s ", user );
 606                 dbgtext( "(uid=%d, gid=%d) ", (int)geteuid(), (int)getegid() );
 607                 dbgtext( "(pid %d)\n", (int)sys_getpid() );
 608         }
 609
 610         /* we've finished with the sensitive stuff */
 611         unbecome_user();
 612
 613         /* Add veto/hide lists */
 614         if (!IS_IPC(conn) && !IS_PRINT(conn)) {
 615                 set_namearray( &conn->veto_list, lp_veto_files(SNUM(conn)));
 616                 set_namearray( &conn->hide_list, lp_hide_files(SNUM(conn)));
 617                 set_namearray( &conn->veto_oplock_list, lp_veto_oplocks(SNUM(conn)));
 618         }
 619
 620         /* Invoke VFS make connection hook */
 621
 622         if (conn->vfs_ops.connect) {
 623                 if (conn->vfs_ops.connect(conn, service, user) < 0)
 624                         return NULL;
 625         }
 626
 627         return(conn);
 628 }
 629
 630
 631 /****************************************************************************
 632 close a cnum
 633 ****************************************************************************/
 634 void close_cnum(connection_struct *conn, uint16 vuid)
 635 {
 636         DirCacheFlush(SNUM(conn));
 637
 638         unbecome_user();
 639
 640         DEBUG(IS_IPC(conn)?3:1, ("%s (%s) closed connection to service %s\n",
 641                                  remote_machine,conn->client_address,
 642                                  lp_servicename(SNUM(conn))));
 643
 644         if (conn->vfs_ops.disconnect != NULL) {
 645
 646             /* Call VFS disconnect hook */
 647
 648             conn->vfs_ops.disconnect(conn);
 649
 650         }
 651
 652         yield_connection(conn,
 653                          lp_servicename(SNUM(conn)),
 654                          lp_max_connections(SNUM(conn)));
 655
 656         file_close_conn(conn);
 657         dptr_closecnum(conn);
 658
 659         /* execute any "postexec = " line */
 660         if (*lp_postexec(SNUM(conn)) &&
 661             become_user(conn, vuid))  {
 662                 pstring cmd;
 663                 pstrcpy(cmd,lp_postexec(SNUM(conn)));
 664                 standard_sub_conn(conn,cmd);
 665                 smbrun(cmd,NULL);
 666                 unbecome_user();
 667         }
 668
 669         unbecome_user();
 670         /* execute any "root postexec = " line */
 671         if (*lp_rootpostexec(SNUM(conn)))  {
 672                 pstring cmd;
 673                 pstrcpy(cmd,lp_rootpostexec(SNUM(conn)));
 674                 standard_sub_conn(conn,cmd);
 675                 smbrun(cmd,NULL);
 676         }
 677         conn_free(conn);
 678 }
 679
 680