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