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 pstring sesssetup_user;
  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             dos_ChDir(conn->connectpath) != 0 &&
  58             dos_ChDir(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 /****************************************************************************
  81   find a service entry
  82 ****************************************************************************/
  83 int find_service(char *service)
  84 {
  85    int iService;
  86
  87    all_string_sub(service,"\\","/",0);
  88
  89    iService = lp_servicenumber(service);
  90
  91    /* now handle the special case of a home directory */
  92    if (iService < 0)
  93    {
  94       char *phome_dir = get_user_home_dir(service);
  95
  96       if(!phome_dir)
  97       {
  98         /*
  99          * Try mapping the servicename, it may
 100          * be a Windows to unix mapped user name.
 101          */
 102         if(map_username(service))
 103           phome_dir = get_user_home_dir(service);
 104       }
 105
 106       DEBUG(3,("checking for home directory %s gave %s\n",service,
 107             phome_dir?phome_dir:"(NULL)"));
 108
 109       if (phome_dir)
 110       {
 111         int iHomeService;
 112         if ((iHomeService = lp_servicenumber(HOMES_NAME)) >= 0)
 113         {
 114           lp_add_home(service,iHomeService,phome_dir);
 115           iService = lp_servicenumber(service);
 116         }
 117       }
 118    }
 119
 120    /* If we still don't have a service, attempt to add it as a printer. */
 121    if (iService < 0)
 122    {
 123       int iPrinterService;
 124
 125       if ((iPrinterService = lp_servicenumber(PRINTERS_NAME)) >= 0)
 126       {
 127          char *pszTemp;
 128
 129          DEBUG(3,("checking whether %s is a valid printer name...\n", service));
 130          pszTemp = PRINTCAP;
 131          if ((pszTemp != NULL) && pcap_printername_ok(service, pszTemp))
 132          {
 133             DEBUG(3,("%s is a valid printer name\n", service));
 134             DEBUG(3,("adding %s as a printer service\n", service));
 135             lp_add_printer(service,iPrinterService);
 136             iService = lp_servicenumber(service);
 137             if (iService < 0)
 138                DEBUG(0,("failed to add %s as a printer service!\n", service));
 139          }
 140          else
 141             DEBUG(3,("%s is not a valid printer name\n", service));
 142       }
 143    }
 144
 145    /* Check for default vfs service?  Unsure whether to implement this */
 146    if (iService < 0)
 147    {
 148    }
 149
 150    /* just possibly it's a default service? */
 151    if (iService < 0)
 152    {
 153      char *pdefservice = lp_defaultservice();
 154      if (pdefservice && *pdefservice &&
 155          !strequal(pdefservice,service) &&
 156          !strstr(service,".."))
 157      {
 158        /*
 159         * We need to do a local copy here as lp_defaultservice()
 160         * returns one of the rotating lp_string buffers that
 161         * could get overwritten by the recursive find_service() call
 162         * below. Fix from Josef Hinteregger <joehtg@joehtg.co.at>.
 163         */
 164        pstring defservice;
 165        pstrcpy(defservice, pdefservice);
 166        iService = find_service(defservice);
 167        if (iService >= 0)
 168        {
 169          all_string_sub(service,"_","/",0);
 170          iService = lp_add_service(service,iService);
 171        }
 172      }
 173    }
 174
 175    if (iService >= 0)
 176      if (!VALID_SNUM(iService))
 177      {
 178        DEBUG(0,("Invalid snum %d for %s\n",iService,service));
 179        iService = -1;
 180      }
 181
 182    if (iService < 0)
 183      DEBUG(3,("find_service() failed to find service %s\n", service));
 184
 185    return (iService);
 186 }
 187
 188
 189 /****************************************************************************
 190   make a connection to a service
 191 ****************************************************************************/
 192 connection_struct *make_connection(char *service,char *user,char *password, int pwlen, char *dev,uint16 vuid, int *ecode)
 193 {
 194         int snum;
 195         struct passwd *pass = NULL;
 196         BOOL guest = False;
 197         BOOL force = False;
 198         connection_struct *conn;
 199         int ret;
 200
 201         strlower(service);
 202
 203         snum = find_service(service);
 204         if (snum < 0) {
 205                 if (strequal(service,"IPC$")) {
 206                         DEBUG(3,("refusing IPC connection\n"));
 207                         *ecode = ERRnoipc;
 208                         return NULL;
 209                 }
 210
 211                 DEBUG(0,("%s (%s) couldn't find service %s\n",
 212                          remote_machine, client_addr(), service));
 213                 *ecode = ERRinvnetname;
 214                 return NULL;
 215         }
 216
 217         if (strequal(service,HOMES_NAME)) {
 218                 if (*user && Get_Pwnam(user,True)) {
 219                         fstring dos_username;
 220                         fstrcpy(dos_username, user);
 221                         unix_to_dos(dos_username, True);
 222                         return(make_connection(dos_username,user,password,
 223                                                pwlen,dev,vuid,ecode));
 224                 }
 225
 226                 if(lp_security() != SEC_SHARE) {
 227                         if (validated_username(vuid)) {
 228                                 fstring dos_username;
 229                                 fstrcpy(user,validated_username(vuid));
 230                                 fstrcpy(dos_username, user);
 231                                 unix_to_dos(dos_username, True);
 232                                 return(make_connection(dos_username,user,password,pwlen,dev,vuid,ecode));
 233                         }
 234                 } else {
 235                         /* Security = share. Try with sesssetup_user
 236                          * as the username.  */
 237                         if(*sesssetup_user) {
 238                                 fstring dos_username;
 239                                 fstrcpy(user,sesssetup_user);
 240                                 fstrcpy(dos_username, user);
 241                                 unix_to_dos(dos_username, True);
 242                                 return(make_connection(dos_username,user,password,pwlen,dev,vuid,ecode));
 243                         }
 244                 }
 245         }
 246
 247         if (!lp_snum_ok(snum) ||
 248             !check_access(smbd_server_fd(),
 249                           lp_hostsallow(snum), lp_hostsdeny(snum))) {
 250                 *ecode = ERRaccess;
 251                 return NULL;
 252         }
 253
 254         /* you can only connect to the IPC$ service as an ipc device */
 255         if (strequal(service,"IPC$"))
 256                 pstrcpy(dev,"IPC");
 257
 258         if (*dev == '?' || !*dev) {
 259                 if (lp_print_ok(snum)) {
 260                         pstrcpy(dev,"LPT1:");
 261                 } else {
 262                         pstrcpy(dev,"A:");
 263                 }
 264         }
 265
 266         /* if the request is as a printer and you can't print then refuse */
 267         strupper(dev);
 268         if (!lp_print_ok(snum) && (strncmp(dev,"LPT",3) == 0)) {
 269                 DEBUG(1,("Attempt to connect to non-printer as a printer\n"));
 270                 *ecode = ERRinvdevice;
 271                 return NULL;
 272         }
 273
 274         /* lowercase the user name */
 275         strlower(user);
 276
 277         /* add it as a possible user name */
 278         add_session_user(service);
 279
 280         /* shall we let them in? */
 281         if (!authorise_login(snum,user,password,pwlen,&guest,&force,vuid)) {
 282                 DEBUG( 2, ( "Invalid username/password for %s\n", service ) );
 283                 *ecode = ERRbadpw;
 284                 return NULL;
 285         }
 286
 287         conn = conn_new();
 288         if (!conn) {
 289                 DEBUG(0,("Couldn't find free connection.\n"));
 290                 *ecode = ERRnoresource;
 291                 conn_free(conn);
 292                 return NULL;
 293         }
 294
 295         /* find out some info about the user */
 296         pass = Get_Pwnam(user,True);
 297
 298         if (pass == NULL) {
 299                 DEBUG(0,( "Couldn't find account %s\n",user));
 300                 *ecode = ERRbaduid;
 301                 conn_free(conn);
 302                 return NULL;
 303         }
 304
 305         conn->read_only = lp_readonly(snum);
 306
 307         {
 308                 pstring list;
 309                 StrnCpy(list,lp_readlist(snum),sizeof(pstring)-1);
 310                 pstring_sub(list,"%S",service);
 311
 312                 if (user_in_list(user,list))
 313                         conn->read_only = True;
 314
 315                 StrnCpy(list,lp_writelist(snum),sizeof(pstring)-1);
 316                 pstring_sub(list,"%S",service);
 317
 318                 if (user_in_list(user,list))
 319                         conn->read_only = False;
 320         }
 321
 322         /* admin user check */
 323
 324         /* JRA - original code denied admin user if the share was
 325            marked read_only. Changed as I don't think this is needed,
 326            but old code left in case there is a problem here.
 327         */
 328         if (user_in_list(user,lp_admin_users(snum))
 329 #if 0
 330             && !conn->read_only
 331 #endif
 332             ) {
 333                 conn->admin_user = True;
 334                 DEBUG(0,("%s logged in as admin user (root privileges)\n",user));
 335         } else {
 336                 conn->admin_user = False;
 337         }
 338
 339         conn->force_user = force;
 340         conn->vuid = vuid;
 341         conn->uid = pass->pw_uid;
 342         conn->gid = pass->pw_gid;
 343         safe_strcpy(conn->client_address, client_addr(), sizeof(conn->client_address)-1);
 344         conn->num_files_open = 0;
 345         conn->lastused = time(NULL);
 346         conn->service = snum;
 347         conn->used = True;
 348         conn->printer = (strncmp(dev,"LPT",3) == 0);
 349         conn->ipc = (strncmp(dev,"IPC",3) == 0);
 350         conn->dirptr = NULL;
 351         conn->veto_list = NULL;
 352         conn->hide_list = NULL;
 353         conn->veto_oplock_list = NULL;
 354         string_set(&conn->dirpath,"");
 355         string_set(&conn->user,user);
 356
 357         conn->vfs_conn = (struct vfs_connection_struct *)
 358             malloc(sizeof(struct vfs_connection_struct));
 359
 360         if (conn->vfs_conn == NULL) {
 361             DEBUG(0, ("No memory to create vfs_connection_struct"));
 362             return NULL;
 363         }
 364
 365         ZERO_STRUCTP(conn->vfs_conn);
 366
 367         /* Copy across relevant data from connection struct */
 368
 369         conn->vfs_conn->printer = conn->printer;
 370         conn->vfs_conn->ipc = conn->ipc;
 371         conn->vfs_conn->read_only = conn->read_only;
 372         conn->vfs_conn->admin_user = conn->admin_user;
 373
 374         pstrcpy(conn->vfs_conn->dirpath, conn->dirpath);
 375         pstrcpy(conn->vfs_conn->connectpath, conn->connectpath);
 376         pstrcpy(conn->vfs_conn->origpath, conn->origpath);
 377
 378         pstrcpy(conn->vfs_conn->service, service);
 379         pstrcpy(conn->vfs_conn->user, conn->user);
 380
 381         conn->vfs_conn->uid = conn->uid;
 382         conn->vfs_conn->gid = conn->gid;
 383         conn->vfs_conn->ngroups = conn->ngroups;
 384         if (conn->vfs_conn->ngroups != 0) {
 385                 conn->vfs_conn->groups = (gid_t *)memdup(conn->groups,
 386                                                          conn->ngroups * sizeof(gid_t));
 387         } else {
 388                 conn->vfs_conn->groups = NULL;
 389         }
 390
 391         /* Initialise VFS function pointers */
 392
 393         if (*lp_vfsobj(SNUM(conn))) {
 394
 395 #ifdef HAVE_LIBDL
 396
 397             /* Loadable object file */
 398
 399             if (!vfs_init_custom(conn)) {
 400                 return NULL;
 401             }
 402 #else
 403             DEBUG(0, ("No libdl present - cannot use VFS objects\n"));
 404             conn_free(conn);
 405             return NULL;
 406 #endif
 407
 408         } else {
 409
 410             /* Normal share - initialise with disk access functions */
 411
 412             vfs_init_default(conn);
 413         }
 414
 415         /*
 416          * If force user is true, then store the
 417          * given userid and also the primary groupid
 418          * of the user we're forcing.
 419          */
 420
 421         if (*lp_force_user(snum)) {
 422                 struct passwd *pass2;
 423                 pstring fuser;
 424                 pstrcpy(fuser,lp_force_user(snum));
 425
 426                 /* Allow %S to be used by force user. */
 427                 pstring_sub(fuser,"%S",service);
 428
 429                 pass2 = (struct passwd *)Get_Pwnam(fuser,True);
 430                 if (pass2) {
 431                         conn->uid = pass2->pw_uid;
 432                         conn->gid = pass2->pw_gid;
 433                         string_set(&conn->user,fuser);
 434                         fstrcpy(user,fuser);
 435                         conn->force_user = True;
 436                         DEBUG(3,("Forced user %s\n",fuser));
 437                 } else {
 438                         DEBUG(1,("Couldn't find user %s\n",fuser));
 439                 }
 440         }
 441
 442 #ifdef HAVE_GETGRNAM
 443         /*
 444          * If force group is true, then override
 445          * any groupid stored for the connecting user.
 446          */
 447
 448         if (*lp_force_group(snum)) {
 449                 struct group *gptr;
 450                 pstring gname;
 451                 pstring tmp_gname;
 452                 BOOL user_must_be_member = False;
 453
 454                 StrnCpy(tmp_gname,lp_force_group(snum),sizeof(pstring)-1);
 455
 456                 if (tmp_gname[0] == '+') {
 457                         user_must_be_member = True;
 458                         StrnCpy(gname,&tmp_gname[1],sizeof(pstring)-2);
 459                 } else {
 460                         StrnCpy(gname,tmp_gname,sizeof(pstring)-1);
 461                 }
 462                 /* default service may be a group name          */
 463                 pstring_sub(gname,"%S",service);
 464                 gptr = (struct group *)getgrnam(gname);
 465
 466                 if (gptr) {
 467                         /*
 468                          * If the user has been forced and the forced group starts
 469                          * with a '+', then we only set the group to be the forced
 470                          * group if the forced user is a member of that group.
 471                          * Otherwise, the meaning of the '+' would be ignored.
 472                          */
 473                         if (conn->force_user && user_must_be_member) {
 474                                 int i;
 475                                 for (i = 0; gptr->gr_mem[i] != NULL; i++) {
 476                                         if (strcmp(user,gptr->gr_mem[i]) == 0) {
 477                                                 conn->gid = gptr->gr_gid;
 478                                                 DEBUG(3,("Forced group %s for member %s\n",gname,user));
 479                                                 break;
 480                                         }
 481                                 }
 482                         } else {
 483                                 conn->gid = gptr->gr_gid;
 484                                 DEBUG(3,("Forced group %s\n",gname));
 485                         }
 486                 } else {
 487                         DEBUG(1,("Couldn't find group %s\n",gname));
 488                 }
 489         }
 490 #endif /* HAVE_GETGRNAM */
 491
 492         {
 493                 pstring s;
 494                 pstrcpy(s,lp_pathname(snum));
 495                 standard_sub_conn(conn,s);
 496                 string_set(&conn->connectpath,s);
 497                 DEBUG(3,("Connect path is %s\n",s));
 498         }
 499
 500         /* groups stuff added by ih */
 501         conn->ngroups = 0;
 502         conn->groups = NULL;
 503
 504         if (!IS_IPC(conn)) {
 505                 /* Find all the groups this uid is in and
 506                    store them. Used by become_user() */
 507                 setup_groups(conn->user,conn->uid,conn->gid,
 508                              &conn->ngroups,&conn->groups);
 509
 510                 /* check number of connections */
 511                 if (!claim_connection(conn,
 512                                       lp_servicename(SNUM(conn)),
 513                                       lp_max_connections(SNUM(conn)),
 514                                       False)) {
 515                         DEBUG(1,("too many connections - rejected\n"));
 516                         *ecode = ERRnoresource;
 517                         conn_free(conn);
 518                         return NULL;
 519                 }
 520
 521                 if (lp_status(SNUM(conn)))
 522                         claim_connection(conn,"",
 523                                          MAXSTATUS,False);
 524         } /* IS_IPC */
 525
 526         /* execute any "root preexec = " line */
 527         if (*lp_rootpreexec(SNUM(conn))) {
 528                 pstring cmd;
 529                 pstrcpy(cmd,lp_rootpreexec(SNUM(conn)));
 530                 standard_sub_conn(conn,cmd);
 531                 DEBUG(5,("cmd=%s\n",cmd));
 532                 ret = smbrun(cmd,NULL,False);
 533                 if (ret != 0 && lp_rootpreexec_close(SNUM(conn))) {
 534                         DEBUG(1,("preexec gave %d - failing connection\n", ret));
 535                         conn_free(conn);
 536                         *ecode = ERRsrverror;
 537                         return NULL;
 538                 }
 539         }
 540
 541         if (!become_user(conn, conn->vuid)) {
 542                 DEBUG(0,("Can't become connected user!\n"));
 543                 if (!IS_IPC(conn)) {
 544                         yield_connection(conn,
 545                                          lp_servicename(SNUM(conn)),
 546                                          lp_max_connections(SNUM(conn)));
 547                         if (lp_status(SNUM(conn))) {
 548                                 yield_connection(conn,"",MAXSTATUS);
 549                         }
 550                 }
 551                 conn_free(conn);
 552                 *ecode = ERRbadpw;
 553                 return NULL;
 554         }
 555
 556         if (dos_ChDir(conn->connectpath) != 0) {
 557                 DEBUG(0,("Can't change directory to %s (%s)\n",
 558                          conn->connectpath,strerror(errno)));
 559                 unbecome_user();
 560                 if (!IS_IPC(conn)) {
 561                         yield_connection(conn,
 562                                          lp_servicename(SNUM(conn)),
 563                                          lp_max_connections(SNUM(conn)));
 564                         if (lp_status(SNUM(conn)))
 565                                 yield_connection(conn,"",MAXSTATUS);
 566                 }
 567                 conn_free(conn);
 568                 *ecode = ERRinvnetname;
 569                 return NULL;
 570         }
 571
 572         string_set(&conn->origpath,conn->connectpath);
 573
 574 #if SOFTLINK_OPTIMISATION
 575         /* resolve any soft links early */
 576         {
 577                 pstring s;
 578                 pstrcpy(s,conn->connectpath);
 579                 dos_GetWd(s);
 580                 string_set(&conn->connectpath,s);
 581                 dos_ChDir(conn->connectpath);
 582         }
 583 #endif
 584
 585         add_session_user(user);
 586
 587         /* execute any "preexec = " line */
 588         if (*lp_preexec(SNUM(conn))) {
 589                 pstring cmd;
 590                 pstrcpy(cmd,lp_preexec(SNUM(conn)));
 591                 standard_sub_conn(conn,cmd);
 592                 ret = smbrun(cmd,NULL,False);
 593                 if (ret != 0 && lp_preexec_close(SNUM(conn))) {
 594                         DEBUG(1,("preexec gave %d - failing connection\n", ret));
 595                         conn_free(conn);
 596                         *ecode = ERRsrverror;
 597                         return NULL;
 598                 }
 599         }
 600
 601         /*
 602          * Print out the 'connected as' stuff here as we need
 603          * to know the effective uid and gid we will be using.
 604          */
 605
 606         if( DEBUGLVL( IS_IPC(conn) ? 3 : 1 ) ) {
 607                 dbgtext( "%s (%s) ", remote_machine, conn->client_address );
 608                 dbgtext( "connect to service %s ", lp_servicename(SNUM(conn)) );
 609                 dbgtext( "as user %s ", user );
 610                 dbgtext( "(uid=%d, gid=%d) ", (int)geteuid(), (int)getegid() );
 611                 dbgtext( "(pid %d)\n", (int)sys_getpid() );
 612         }
 613
 614         /* we've finished with the sensitive stuff */
 615         unbecome_user();
 616
 617         /* Add veto/hide lists */
 618         if (!IS_IPC(conn) && !IS_PRINT(conn)) {
 619                 set_namearray( &conn->veto_list, lp_veto_files(SNUM(conn)));
 620                 set_namearray( &conn->hide_list, lp_hide_files(SNUM(conn)));
 621                 set_namearray( &conn->veto_oplock_list, lp_veto_oplocks(SNUM(conn)));
 622         }
 623
 624         /* Invoke VFS make connection hook */
 625
 626         if (conn->vfs_ops.connect) {
 627             if (conn->vfs_ops.connect(conn->vfs_conn, service, user) < 0) {
 628                 return NULL;
 629             }
 630         }
 631
 632         return(conn);
 633 }
 634
 635
 636 /****************************************************************************
 637 close a cnum
 638 ****************************************************************************/
 639 void close_cnum(connection_struct *conn, uint16 vuid)
 640 {
 641         DirCacheFlush(SNUM(conn));
 642
 643         unbecome_user();
 644
 645         DEBUG(IS_IPC(conn)?3:1, ("%s (%s) closed connection to service %s\n",
 646                                  remote_machine,conn->client_address,
 647                                  lp_servicename(SNUM(conn))));
 648
 649         if (conn->vfs_ops.disconnect != NULL) {
 650
 651             /* Call VFS disconnect hook */
 652
 653             conn->vfs_ops.disconnect();
 654
 655         }
 656
 657         yield_connection(conn,
 658                          lp_servicename(SNUM(conn)),
 659                          lp_max_connections(SNUM(conn)));
 660
 661         if (lp_status(SNUM(conn)))
 662                 yield_connection(conn,"",MAXSTATUS);
 663
 664         file_close_conn(conn);
 665         dptr_closecnum(conn);
 666
 667         /* execute any "postexec = " line */
 668         if (*lp_postexec(SNUM(conn)) &&
 669             become_user(conn, vuid))  {
 670                 pstring cmd;
 671                 pstrcpy(cmd,lp_postexec(SNUM(conn)));
 672                 standard_sub_conn(conn,cmd);
 673                 smbrun(cmd,NULL,False);
 674                 unbecome_user();
 675         }
 676
 677         unbecome_user();
 678         /* execute any "root postexec = " line */
 679         if (*lp_rootpostexec(SNUM(conn)))  {
 680                 pstring cmd;
 681                 pstrcpy(cmd,lp_rootpostexec(SNUM(conn)));
 682                 standard_sub_conn(conn,cmd);
 683                 smbrun(cmd,NULL,False);
 684         }
 685         conn_free(conn);
 686 }