source3/smbd/service.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    service (connection) opening and closing
   4    Copyright (C) Andrew Tridgell 1992-1998
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "smbd/globals.h"
  22
  23 extern userdom_struct current_user_info;
  24
  25 static bool canonicalize_connect_path(connection_struct *conn)
  26 {
  27 #ifdef REALPATH_TAKES_NULL
  28         bool ret;
  29         char *resolved_name = SMB_VFS_REALPATH(conn,conn->connectpath,NULL);
  30         if (!resolved_name) {
  31                 return false;
  32         }
  33         ret = set_conn_connectpath(conn,resolved_name);
  34         SAFE_FREE(resolved_name);
  35         return ret;
  36 #else
  37         char resolved_name_buf[PATH_MAX+1];
  38         char *resolved_name = SMB_VFS_REALPATH(conn,conn->connectpath,resolved_name_buf);
  39         if (!resolved_name) {
  40                 return false;
  41         }
  42         return set_conn_connectpath(conn,resolved_name);
  43 #endif /* REALPATH_TAKES_NULL */
  44 }
  45
  46 /****************************************************************************
  47  Ensure when setting connectpath it is a canonicalized (no ./ // or ../)
  48  absolute path stating in / and not ending in /.
  49  Observent people will notice a similarity between this and check_path_syntax :-).
  50 ****************************************************************************/
  51
  52 bool set_conn_connectpath(connection_struct *conn, const char *connectpath)
  53 {
  54         char *destname;
  55         char *d;
  56         const char *s = connectpath;
  57         bool start_of_name_component = true;
  58
  59         if (connectpath == NULL || connectpath[0] == '\0') {
  60                 return false;
  61         }
  62
  63         /* Allocate for strlen + '\0' + possible leading '/' */
  64         destname = SMB_MALLOC(strlen(connectpath) + 2);
  65         if (!destname) {
  66                 return false;
  67         }
  68         d = destname;
  69
  70         *d++ = '/'; /* Always start with root. */
  71
  72         while (*s) {
  73                 if (*s == '/') {
  74                         /* Eat multiple '/' */
  75                         while (*s == '/') {
  76                                 s++;
  77                         }
  78                         if ((d > destname + 1) && (*s != '\0')) {
  79                                 *d++ = '/';
  80                         }
  81                         start_of_name_component = True;
  82                         continue;
  83                 }
  84
  85                 if (start_of_name_component) {
  86                         if ((s[0] == '.') && (s[1] == '.') && (s[2] == '/' || s[2] == '\0')) {
  87                                 /* Uh oh - "/../" or "/..\0" ! */
  88
  89                                 /* Go past the ../ or .. */
  90                                 if (s[2] == '/') {
  91                                         s += 3;
  92                                 } else {
  93                                         s += 2; /* Go past the .. */
  94                                 }
  95
  96                                 /* If  we just added a '/' - delete it */
  97                                 if ((d > destname) && (*(d-1) == '/')) {
  98                                         *(d-1) = '\0';
  99                                         d--;
 100                                 }
 101
 102                                 /* Are we at the start ? Can't go back further if so. */
 103                                 if (d <= destname) {
 104                                         *d++ = '/'; /* Can't delete root */
 105                                         continue;
 106                                 }
 107                                 /* Go back one level... */
 108                                 /* Decrement d first as d points to the *next* char to write into. */
 109                                 for (d--; d > destname; d--) {
 110                                         if (*d == '/') {
 111                                                 break;
 112                                         }
 113                                 }
 114                                 /* We're still at the start of a name component, just the previous one. */
 115                                 continue;
 116                         } else if ((s[0] == '.') && ((s[1] == '\0') || s[1] == '/')) {
 117                                 /* Component of pathname can't be "." only - skip the '.' . */
 118                                 if (s[1] == '/') {
 119                                         s += 2;
 120                                 } else {
 121                                         s++;
 122                                 }
 123                                 continue;
 124                         }
 125                 }
 126
 127                 if (!(*s & 0x80)) {
 128                         *d++ = *s++;
 129                 } else {
 130                         size_t siz;
 131                         /* Get the size of the next MB character. */
 132                         next_codepoint(s,&siz);
 133                         switch(siz) {
 134                                 case 5:
 135                                         *d++ = *s++;
 136                                         /*fall through*/
 137                                 case 4:
 138                                         *d++ = *s++;
 139                                         /*fall through*/
 140                                 case 3:
 141                                         *d++ = *s++;
 142                                         /*fall through*/
 143                                 case 2:
 144                                         *d++ = *s++;
 145                                         /*fall through*/
 146                                 case 1:
 147                                         *d++ = *s++;
 148                                         break;
 149                                 default:
 150                                         break;
 151                         }
 152                 }
 153                 start_of_name_component = false;
 154         }
 155         *d = '\0';
 156
 157         /* And must not end in '/' */
 158         if (d > destname + 1 && (*(d-1) == '/')) {
 159                 *(d-1) = '\0';
 160         }
 161
 162         DEBUG(10,("set_conn_connectpath: service %s, connectpath = %s\n",
 163                 lp_servicename(SNUM(conn)), destname ));
 164
 165         string_set(&conn->connectpath, destname);
 166         SAFE_FREE(destname);
 167         return true;
 168 }
 169
 170 /****************************************************************************
 171  Load parameters specific to a connection/service.
 172 ****************************************************************************/
 173
 174 bool set_current_service(connection_struct *conn, uint16 flags, bool do_chdir)
 175 {
 176         int snum;
 177
 178         if (!conn)  {
 179                 last_conn = NULL;
 180                 return(False);
 181         }
 182
 183         conn->lastused_count++;
 184
 185         snum = SNUM(conn);
 186
 187         if (do_chdir &&
 188             vfs_ChDir(conn,conn->connectpath) != 0 &&
 189             vfs_ChDir(conn,conn->origpath) != 0) {
 190                 DEBUG(((errno!=EACCES)?0:3),("chdir (%s) failed, reason: %s\n",
 191                          conn->connectpath, strerror(errno)));
 192                 return(False);
 193         }
 194
 195         if ((conn == last_conn) && (last_flags == flags)) {
 196                 return(True);
 197         }
 198
 199         last_conn = conn;
 200         last_flags = flags;
 201
 202         /* Obey the client case sensitivity requests - only for clients that support it. */
 203         switch (lp_casesensitive(snum)) {
 204                 case Auto:
 205                         {
 206                                 /* We need this uglyness due to DOS/Win9x clients that lie about case insensitivity. */
 207                                 enum remote_arch_types ra_type = get_remote_arch();
 208                                 if ((ra_type != RA_SAMBA) && (ra_type != RA_CIFSFS)) {
 209                                         /* Client can't support per-packet case sensitive pathnames. */
 210                                         conn->case_sensitive = False;
 211                                 } else {
 212                                         conn->case_sensitive = !(flags & FLAG_CASELESS_PATHNAMES);
 213                                 }
 214                         }
 215                         break;
 216                 case True:
 217                         conn->case_sensitive = True;
 218                         break;
 219                 default:
 220                         conn->case_sensitive = False;
 221                         break;
 222         }
 223         return(True);
 224 }
 225
 226 static int load_registry_service(const char *servicename)
 227 {
 228         if (!lp_registry_shares()) {
 229                 return -1;
 230         }
 231
 232         if ((servicename == NULL) || (*servicename == '\0')) {
 233                 return -1;
 234         }
 235
 236         if (strequal(servicename, GLOBAL_NAME)) {
 237                 return -2;
 238         }
 239
 240         if (!process_registry_service(servicename)) {
 241                 return -1;
 242         }
 243
 244         return lp_servicenumber(servicename);
 245 }
 246
 247 void load_registry_shares(void)
 248 {
 249         DEBUG(8, ("load_registry_shares()\n"));
 250         if (!lp_registry_shares()) {
 251                 return;
 252         }
 253
 254         process_registry_shares();
 255
 256         return;
 257 }
 258
 259 /****************************************************************************
 260  Add a home service. Returns the new service number or -1 if fail.
 261 ****************************************************************************/
 262
 263 int add_home_service(const char *service, const char *username, const char *homedir)
 264 {
 265         int iHomeService;
 266
 267         if (!service || !homedir || homedir[0] == '\0')
 268                 return -1;
 269
 270         if ((iHomeService = lp_servicenumber(HOMES_NAME)) < 0) {
 271                 if ((iHomeService = load_registry_service(HOMES_NAME)) < 0) {
 272                         return -1;
 273                 }
 274         }
 275
 276         /*
 277          * If this is a winbindd provided username, remove
 278          * the domain component before adding the service.
 279          * Log a warning if the "path=" parameter does not
 280          * include any macros.
 281          */
 282
 283         {
 284                 const char *p = strchr(service,*lp_winbind_separator());
 285
 286                 /* We only want the 'user' part of the string */
 287                 if (p) {
 288                         service = p + 1;
 289                 }
 290         }
 291
 292         if (!lp_add_home(service, iHomeService, username, homedir)) {
 293                 return -1;
 294         }
 295
 296         return lp_servicenumber(service);
 297
 298 }
 299
 300 /**
 301  * Find a service entry.
 302  *
 303  * @param service is modified (to canonical form??)
 304  **/
 305
 306 int find_service(fstring service)
 307 {
 308         int iService;
 309         struct smbd_server_connection *sconn = smbd_server_conn;
 310
 311         all_string_sub(service,"\\","/",0);
 312
 313         iService = lp_servicenumber(service);
 314
 315         /* now handle the special case of a home directory */
 316         if (iService < 0) {
 317                 char *phome_dir = get_user_home_dir(talloc_tos(), service);
 318
 319                 if(!phome_dir) {
 320                         /*
 321                          * Try mapping the servicename, it may
 322                          * be a Windows to unix mapped user name.
 323                          */
 324                         if(map_username(sconn, service))
 325                                 phome_dir = get_user_home_dir(
 326                                         talloc_tos(), service);
 327                 }
 328
 329                 DEBUG(3,("checking for home directory %s gave %s\n",service,
 330                         phome_dir?phome_dir:"(NULL)"));
 331
 332                 iService = add_home_service(service,service /* 'username' */, phome_dir);
 333         }
 334
 335         /* If we still don't have a service, attempt to add it as a printer. */
 336         if (iService < 0) {
 337                 int iPrinterService;
 338
 339                 if ((iPrinterService = lp_servicenumber(PRINTERS_NAME)) < 0) {
 340                         iPrinterService = load_registry_service(PRINTERS_NAME);
 341                 }
 342                 if (iPrinterService) {
 343                         DEBUG(3,("checking whether %s is a valid printer name...\n", service));
 344                         if (pcap_printername_ok(service)) {
 345                                 DEBUG(3,("%s is a valid printer name\n", service));
 346                                 DEBUG(3,("adding %s as a printer service\n", service));
 347                                 lp_add_printer(service, iPrinterService);
 348                                 iService = lp_servicenumber(service);
 349                                 if (iService < 0) {
 350                                         DEBUG(0,("failed to add %s as a printer service!\n", service));
 351                                 }
 352                         } else {
 353                                 DEBUG(3,("%s is not a valid printer name\n", service));
 354                         }
 355                 }
 356         }
 357
 358         /* Check for default vfs service?  Unsure whether to implement this */
 359         if (iService < 0) {
 360         }
 361
 362         if (iService < 0) {
 363                 iService = load_registry_service(service);
 364         }
 365
 366         /* Is it a usershare service ? */
 367         if (iService < 0 && *lp_usershare_path()) {
 368                 /* Ensure the name is canonicalized. */
 369                 strlower_m(service);
 370                 iService = load_usershare_service(service);
 371         }
 372
 373         /* just possibly it's a default service? */
 374         if (iService < 0) {
 375                 char *pdefservice = lp_defaultservice();
 376                 if (pdefservice && *pdefservice && !strequal(pdefservice,service) && !strstr_m(service,"..")) {
 377                         /*
 378                          * We need to do a local copy here as lp_defaultservice()
 379                          * returns one of the rotating lp_string buffers that
 380                          * could get overwritten by the recursive find_service() call
 381                          * below. Fix from Josef Hinteregger <joehtg@joehtg.co.at>.
 382                          */
 383                         char *defservice = SMB_STRDUP(pdefservice);
 384
 385                         if (!defservice) {
 386                                 goto fail;
 387                         }
 388
 389                         /* Disallow anything except explicit share names. */
 390                         if (strequal(defservice,HOMES_NAME) ||
 391                                         strequal(defservice, PRINTERS_NAME) ||
 392                                         strequal(defservice, "IPC$")) {
 393                                 SAFE_FREE(defservice);
 394                                 goto fail;
 395                         }
 396
 397                         iService = find_service(defservice);
 398                         if (iService >= 0) {
 399                                 all_string_sub(service, "_","/",0);
 400                                 iService = lp_add_service(service, iService);
 401                         }
 402                         SAFE_FREE(defservice);
 403                 }
 404         }
 405
 406         if (iService >= 0) {
 407                 if (!VALID_SNUM(iService)) {
 408                         DEBUG(0,("Invalid snum %d for %s\n",iService, service));
 409                         iService = -1;
 410                 }
 411         }
 412
 413   fail:
 414
 415         if (iService < 0)
 416                 DEBUG(3,("find_service() failed to find service %s\n", service));
 417
 418         return (iService);
 419 }
 420
 421
 422 /****************************************************************************
 423  do some basic sainity checks on the share.
 424  This function modifies dev, ecode.
 425 ****************************************************************************/
 426
 427 static NTSTATUS share_sanity_checks(int snum, fstring dev)
 428 {
 429
 430         if (!lp_snum_ok(snum) ||
 431             !check_access(smbd_server_fd(),
 432                           lp_hostsallow(snum), lp_hostsdeny(snum))) {
 433                 return NT_STATUS_ACCESS_DENIED;
 434         }
 435
 436         if (dev[0] == '?' || !dev[0]) {
 437                 if (lp_print_ok(snum)) {
 438                         fstrcpy(dev,"LPT1:");
 439                 } else if (strequal(lp_fstype(snum), "IPC")) {
 440                         fstrcpy(dev, "IPC");
 441                 } else {
 442                         fstrcpy(dev,"A:");
 443                 }
 444         }
 445
 446         strupper_m(dev);
 447
 448         if (lp_print_ok(snum)) {
 449                 if (!strequal(dev, "LPT1:")) {
 450                         return NT_STATUS_BAD_DEVICE_TYPE;
 451                 }
 452         } else if (strequal(lp_fstype(snum), "IPC")) {
 453                 if (!strequal(dev, "IPC")) {
 454                         return NT_STATUS_BAD_DEVICE_TYPE;
 455                 }
 456         } else if (!strequal(dev, "A:")) {
 457                 return NT_STATUS_BAD_DEVICE_TYPE;
 458         }
 459
 460         /* Behave as a printer if we are supposed to */
 461         if (lp_print_ok(snum) && (strcmp(dev, "A:") == 0)) {
 462                 fstrcpy(dev, "LPT1:");
 463         }
 464
 465         return NT_STATUS_OK;
 466 }
 467
 468 /*
 469  * Go through lookup_name etc to find the force'd group.
 470  *
 471  * Create a new token from src_token, replacing the primary group sid with the
 472  * one found.
 473  */
 474
 475 static NTSTATUS find_forced_group(bool force_user,
 476                                   int snum, const char *username,
 477                                   DOM_SID *pgroup_sid,
 478                                   gid_t *pgid)
 479 {
 480         NTSTATUS result = NT_STATUS_NO_SUCH_GROUP;
 481         TALLOC_CTX *frame = talloc_stackframe();
 482         DOM_SID group_sid;
 483         enum lsa_SidType type;
 484         char *groupname;
 485         bool user_must_be_member = False;
 486         gid_t gid;
 487
 488         groupname = talloc_strdup(talloc_tos(), lp_force_group(snum));
 489         if (groupname == NULL) {
 490                 DEBUG(1, ("talloc_strdup failed\n"));
 491                 result = NT_STATUS_NO_MEMORY;
 492                 goto done;
 493         }
 494
 495         if (groupname[0] == '+') {
 496                 user_must_be_member = True;
 497                 groupname += 1;
 498         }
 499
 500         groupname = talloc_string_sub(talloc_tos(), groupname,
 501                                       "%S", lp_servicename(snum));
 502         if (groupname == NULL) {
 503                 DEBUG(1, ("talloc_string_sub failed\n"));
 504                 result = NT_STATUS_NO_MEMORY;
 505                 goto done;
 506         }
 507
 508         if (!lookup_name_smbconf(talloc_tos(), groupname,
 509                          LOOKUP_NAME_ALL|LOOKUP_NAME_GROUP,
 510                          NULL, NULL, &group_sid, &type)) {
 511                 DEBUG(10, ("lookup_name_smbconf(%s) failed\n",
 512                            groupname));
 513                 goto done;
 514         }
 515
 516         if ((type != SID_NAME_DOM_GRP) && (type != SID_NAME_ALIAS) &&
 517             (type != SID_NAME_WKN_GRP)) {
 518                 DEBUG(10, ("%s is a %s, not a group\n", groupname,
 519                            sid_type_lookup(type)));
 520                 goto done;
 521         }
 522
 523         if (!sid_to_gid(&group_sid, &gid)) {
 524                 DEBUG(10, ("sid_to_gid(%s) for %s failed\n",
 525                            sid_string_dbg(&group_sid), groupname));
 526                 goto done;
 527         }
 528
 529         /*
 530          * If the user has been forced and the forced group starts with a '+',
 531          * then we only set the group to be the forced group if the forced
 532          * user is a member of that group.  Otherwise, the meaning of the '+'
 533          * would be ignored.
 534          */
 535
 536         if (force_user && user_must_be_member) {
 537                 if (user_in_group_sid(username, &group_sid)) {
 538                         sid_copy(pgroup_sid, &group_sid);
 539                         *pgid = gid;
 540                         DEBUG(3,("Forced group %s for member %s\n",
 541                                  groupname, username));
 542                 } else {
 543                         DEBUG(0,("find_forced_group: forced user %s is not a member "
 544                                 "of forced group %s. Disallowing access.\n",
 545                                 username, groupname ));
 546                         result = NT_STATUS_MEMBER_NOT_IN_GROUP;
 547                         goto done;
 548                 }
 549         } else {
 550                 sid_copy(pgroup_sid, &group_sid);
 551                 *pgid = gid;
 552                 DEBUG(3,("Forced group %s\n", groupname));
 553         }
 554
 555         result = NT_STATUS_OK;
 556  done:
 557         TALLOC_FREE(frame);
 558         return result;
 559 }
 560
 561 /****************************************************************************
 562   Create an auth_serversupplied_info structure for a connection_struct
 563 ****************************************************************************/
 564
 565 static NTSTATUS create_connection_server_info(struct smbd_server_connection *sconn,
 566                                               TALLOC_CTX *mem_ctx, int snum,
 567                                               struct auth_serversupplied_info *vuid_serverinfo,
 568                                               DATA_BLOB password,
 569                                               struct auth_serversupplied_info **presult)
 570 {
 571         if (lp_guest_only(snum)) {
 572                 return make_server_info_guest(mem_ctx, presult);
 573         }
 574
 575         if (vuid_serverinfo != NULL) {
 576
 577                 struct auth_serversupplied_info *result;
 578
 579                 /*
 580                  * This is the normal security != share case where we have a
 581                  * valid vuid from the session setup.                 */
 582
 583                 if (vuid_serverinfo->guest) {
 584                         if (!lp_guest_ok(snum)) {
 585                                 DEBUG(2, ("guest user (from session setup) "
 586                                           "not permitted to access this share "
 587                                           "(%s)\n", lp_servicename(snum)));
 588                                 return NT_STATUS_ACCESS_DENIED;
 589                         }
 590                 } else {
 591                         if (!user_ok_token(vuid_serverinfo->unix_name,
 592                                            pdb_get_domain(vuid_serverinfo->sam_account),
 593                                            vuid_serverinfo->ptok, snum)) {
 594                                 DEBUG(2, ("user '%s' (from session setup) not "
 595                                           "permitted to access this share "
 596                                           "(%s)\n",
 597                                           vuid_serverinfo->unix_name,
 598                                           lp_servicename(snum)));
 599                                 return NT_STATUS_ACCESS_DENIED;
 600                         }
 601                 }
 602
 603                 result = copy_serverinfo(mem_ctx, vuid_serverinfo);
 604                 if (result == NULL) {
 605                         return NT_STATUS_NO_MEMORY;
 606                 }
 607
 608                 *presult = result;
 609                 return NT_STATUS_OK;
 610         }
 611
 612         if (lp_security() == SEC_SHARE) {
 613
 614                 fstring user;
 615                 bool guest;
 616
 617                 /* add the sharename as a possible user name if we
 618                    are in share mode security */
 619
 620                 add_session_user(sconn, lp_servicename(snum));
 621
 622                 /* shall we let them in? */
 623
 624                 if (!authorise_login(sconn, snum,user,password,&guest)) {
 625                         DEBUG( 2, ( "Invalid username/password for [%s]\n",
 626                                     lp_servicename(snum)) );
 627                         return NT_STATUS_WRONG_PASSWORD;
 628                 }
 629
 630                 return make_serverinfo_from_username(mem_ctx, user, guest,
 631                                                      presult);
 632         }
 633
 634         DEBUG(0, ("invalid VUID (vuser) but not in security=share\n"));
 635         return NT_STATUS_ACCESS_DENIED;
 636 }
 637
 638
 639 /****************************************************************************
 640   Make a connection, given the snum to connect to, and the vuser of the
 641   connecting user if appropriate.
 642 ****************************************************************************/
 643
 644 connection_struct *make_connection_snum(struct smbd_server_connection *sconn,
 645                                         int snum, user_struct *vuser,
 646                                         DATA_BLOB password,
 647                                         const char *pdev,
 648                                         NTSTATUS *pstatus)
 649 {
 650         connection_struct *conn;
 651         struct smb_filename *smb_fname_cpath = NULL;
 652         fstring dev;
 653         int ret;
 654         char addr[INET6_ADDRSTRLEN];
 655         bool on_err_call_dis_hook = false;
 656         NTSTATUS status;
 657
 658         fstrcpy(dev, pdev);
 659
 660         if (NT_STATUS_IS_ERR(*pstatus = share_sanity_checks(snum, dev))) {
 661                 return NULL;
 662         }
 663
 664         conn = conn_new(sconn);
 665         if (!conn) {
 666                 DEBUG(0,("Couldn't find free connection.\n"));
 667                 *pstatus = NT_STATUS_INSUFFICIENT_RESOURCES;
 668                 return NULL;
 669         }
 670
 671         conn->params->service = snum;
 672
 673         status = create_connection_server_info(sconn,
 674                 conn, snum, vuser ? vuser->server_info : NULL, password,
 675                 &conn->server_info);
 676
 677         if (!NT_STATUS_IS_OK(status)) {
 678                 DEBUG(1, ("create_connection_server_info failed: %s\n",
 679                           nt_errstr(status)));
 680                 *pstatus = status;
 681                 conn_free(conn);
 682                 return NULL;
 683         }
 684
 685         if ((lp_guest_only(snum)) || (lp_security() == SEC_SHARE)) {
 686                 conn->force_user = true;
 687         }
 688
 689         add_session_user(sconn, conn->server_info->unix_name);
 690
 691         safe_strcpy(conn->client_address,
 692                         client_addr(get_client_fd(),addr,sizeof(addr)),
 693                         sizeof(conn->client_address)-1);
 694         conn->num_files_open = 0;
 695         conn->lastused = conn->lastused_count = time(NULL);
 696         conn->used = True;
 697         conn->printer = (strncmp(dev,"LPT",3) == 0);
 698         conn->ipc = ( (strncmp(dev,"IPC",3) == 0) ||
 699                       ( lp_enable_asu_support() && strequal(dev,"ADMIN$")) );
 700
 701         /* Case options for the share. */
 702         if (lp_casesensitive(snum) == Auto) {
 703                 /* We will be setting this per packet. Set to be case
 704                  * insensitive for now. */
 705                 conn->case_sensitive = False;
 706         } else {
 707                 conn->case_sensitive = (bool)lp_casesensitive(snum);
 708         }
 709
 710         conn->case_preserve = lp_preservecase(snum);
 711         conn->short_case_preserve = lp_shortpreservecase(snum);
 712
 713         conn->encrypt_level = lp_smb_encrypt(snum);
 714
 715         conn->veto_list = NULL;
 716         conn->hide_list = NULL;
 717         conn->veto_oplock_list = NULL;
 718         conn->aio_write_behind_list = NULL;
 719
 720         conn->read_only = lp_readonly(SNUM(conn));
 721         conn->admin_user = False;
 722
 723         if (*lp_force_user(snum)) {
 724
 725                 /*
 726                  * Replace conn->server_info with a completely faked up one
 727                  * from the username we are forced into :-)
 728                  */
 729
 730                 char *fuser;
 731                 struct auth_serversupplied_info *forced_serverinfo;
 732
 733                 fuser = talloc_string_sub(conn, lp_force_user(snum), "%S",
 734                                           lp_servicename(snum));
 735                 if (fuser == NULL) {
 736                         conn_free(conn);
 737                         *pstatus = NT_STATUS_NO_MEMORY;
 738                         return NULL;
 739                 }
 740
 741                 status = make_serverinfo_from_username(
 742                         conn, fuser, conn->server_info->guest,
 743                         &forced_serverinfo);
 744                 if (!NT_STATUS_IS_OK(status)) {
 745                         conn_free(conn);
 746                         *pstatus = status;
 747                         return NULL;
 748                 }
 749
 750                 TALLOC_FREE(conn->server_info);
 751                 conn->server_info = forced_serverinfo;
 752
 753                 conn->force_user = True;
 754                 DEBUG(3,("Forced user %s\n", fuser));
 755         }
 756
 757         /*
 758          * If force group is true, then override
 759          * any groupid stored for the connecting user.
 760          */
 761
 762         if (*lp_force_group(snum)) {
 763
 764                 status = find_forced_group(
 765                         conn->force_user, snum, conn->server_info->unix_name,
 766                         &conn->server_info->ptok->user_sids[1],
 767                         &conn->server_info->utok.gid);
 768
 769                 if (!NT_STATUS_IS_OK(status)) {
 770                         conn_free(conn);
 771                         *pstatus = status;
 772                         return NULL;
 773                 }
 774
 775                 /*
 776                  * We need to cache this gid, to use within
 777                  * change_to_user() separately from the conn->server_info
 778                  * struct. We only use conn->server_info directly if
 779                  * "force_user" was set.
 780                  */
 781                 conn->force_group_gid = conn->server_info->utok.gid;
 782         }
 783
 784         conn->vuid = (vuser != NULL) ? vuser->vuid : UID_FIELD_INVALID;
 785
 786         {
 787                 char *s = talloc_sub_advanced(talloc_tos(),
 788                                         lp_servicename(SNUM(conn)),
 789                                         conn->server_info->unix_name,
 790                                         conn->connectpath,
 791                                         conn->server_info->utok.gid,
 792                                         conn->server_info->sanitized_username,
 793                                         pdb_get_domain(conn->server_info->sam_account),
 794                                         lp_pathname(snum));
 795                 if (!s) {
 796                         conn_free(conn);
 797                         *pstatus = NT_STATUS_NO_MEMORY;
 798                         return NULL;
 799                 }
 800
 801                 if (!set_conn_connectpath(conn,s)) {
 802                         TALLOC_FREE(s);
 803                         conn_free(conn);
 804                         *pstatus = NT_STATUS_NO_MEMORY;
 805                         return NULL;
 806                 }
 807                 DEBUG(3,("Connect path is '%s' for service [%s]\n",s,
 808                          lp_servicename(snum)));
 809                 TALLOC_FREE(s);
 810         }
 811
 812         /*
 813          * New code to check if there's a share security descripter
 814          * added from NT server manager. This is done after the
 815          * smb.conf checks are done as we need a uid and token. JRA.
 816          *
 817          */
 818
 819         {
 820                 bool can_write = False;
 821
 822                 can_write = share_access_check(conn->server_info->ptok,
 823                                                lp_servicename(snum),
 824                                                FILE_WRITE_DATA);
 825
 826                 if (!can_write) {
 827                         if (!share_access_check(conn->server_info->ptok,
 828                                                 lp_servicename(snum),
 829                                                 FILE_READ_DATA)) {
 830                                 /* No access, read or write. */
 831                                 DEBUG(0,("make_connection: connection to %s "
 832                                          "denied due to security "
 833                                          "descriptor.\n",
 834                                           lp_servicename(snum)));
 835                                 conn_free(conn);
 836                                 *pstatus = NT_STATUS_ACCESS_DENIED;
 837                                 return NULL;
 838                         } else {
 839                                 conn->read_only = True;
 840                         }
 841                 }
 842         }
 843         /* Initialise VFS function pointers */
 844
 845         if (!smbd_vfs_init(conn)) {
 846                 DEBUG(0, ("vfs_init failed for service %s\n",
 847                           lp_servicename(snum)));
 848                 conn_free(conn);
 849                 *pstatus = NT_STATUS_BAD_NETWORK_NAME;
 850                 return NULL;
 851         }
 852
 853         if ((!conn->printer) && (!conn->ipc)) {
 854                 conn->notify_ctx = notify_init(conn, server_id_self(),
 855                                                smbd_messaging_context(),
 856                                                smbd_event_context(),
 857                                                conn);
 858         }
 859
 860 /* ROOT Activities: */
 861         /* explicitly check with lp_widelinks() instead of using
 862          * lp_safe_widelinks() here so that we can correctly warn
 863          * in the logs. */
 864         if (lp_unix_extensions() && lp_widelinks(snum)) {
 865                 DEBUG(0,("Share '%s' has wide links and unix extensions enabled. "
 866                         "These parameters are incompatible. "
 867                         "Wide links will be disabled for this share.\n",
 868                         lp_servicename(snum) ));
 869         }
 870
 871         /*
 872          * Enforce the max connections parameter.
 873          */
 874
 875         if ((lp_max_connections(snum) > 0)
 876             && (count_current_connections(lp_servicename(SNUM(conn)), True) >=
 877                 lp_max_connections(snum))) {
 878
 879                 DEBUG(1, ("Max connections (%d) exceeded for %s\n",
 880                           lp_max_connections(snum), lp_servicename(snum)));
 881                 conn_free(conn);
 882                 *pstatus = NT_STATUS_INSUFFICIENT_RESOURCES;
 883                 return NULL;
 884         }
 885
 886         /*
 887          * Get us an entry in the connections db
 888          */
 889         if (!claim_connection(conn, lp_servicename(snum), 0)) {
 890                 DEBUG(1, ("Could not store connections entry\n"));
 891                 conn_free(conn);
 892                 *pstatus = NT_STATUS_INTERNAL_DB_ERROR;
 893                 return NULL;
 894         }
 895
 896         /*
 897          * Fix compatibility issue pointed out by Volker.
 898          * We pass the conn->connectpath to the preexec
 899          * scripts as a parameter, so attempt to canonicalize
 900          * it here before calling the preexec scripts.
 901          * We ignore errors here, as it is possible that
 902          * the conn->connectpath doesn't exist yet and
 903          * the preexec scripts will create them.
 904          */
 905
 906         (void)canonicalize_connect_path(conn);
 907
 908         /* Preexecs are done here as they might make the dir we are to ChDir
 909          * to below */
 910         /* execute any "root preexec = " line */
 911         if (*lp_rootpreexec(snum)) {
 912                 char *cmd = talloc_sub_advanced(talloc_tos(),
 913                                         lp_servicename(SNUM(conn)),
 914                                         conn->server_info->unix_name,
 915                                         conn->connectpath,
 916                                         conn->server_info->utok.gid,
 917                                         conn->server_info->sanitized_username,
 918                                         pdb_get_domain(conn->server_info->sam_account),
 919                                         lp_rootpreexec(snum));
 920                 DEBUG(5,("cmd=%s\n",cmd));
 921                 ret = smbrun(cmd,NULL);
 922                 TALLOC_FREE(cmd);
 923                 if (ret != 0 && lp_rootpreexec_close(snum)) {
 924                         DEBUG(1,("root preexec gave %d - failing "
 925                                  "connection\n", ret));
 926                         yield_connection(conn, lp_servicename(snum));
 927                         conn_free(conn);
 928                         *pstatus = NT_STATUS_ACCESS_DENIED;
 929                         return NULL;
 930                 }
 931         }
 932
 933 /* USER Activites: */
 934         if (!change_to_user(conn, conn->vuid)) {
 935                 /* No point continuing if they fail the basic checks */
 936                 DEBUG(0,("Can't become connected user!\n"));
 937                 yield_connection(conn, lp_servicename(snum));
 938                 conn_free(conn);
 939                 *pstatus = NT_STATUS_LOGON_FAILURE;
 940                 return NULL;
 941         }
 942
 943         /* Remember that a different vuid can connect later without these
 944          * checks... */
 945
 946         /* Preexecs are done here as they might make the dir we are to ChDir
 947          * to below */
 948
 949         /* execute any "preexec = " line */
 950         if (*lp_preexec(snum)) {
 951                 char *cmd = talloc_sub_advanced(talloc_tos(),
 952                                         lp_servicename(SNUM(conn)),
 953                                         conn->server_info->unix_name,
 954                                         conn->connectpath,
 955                                         conn->server_info->utok.gid,
 956                                         conn->server_info->sanitized_username,
 957                                         pdb_get_domain(conn->server_info->sam_account),
 958                                         lp_preexec(snum));
 959                 ret = smbrun(cmd,NULL);
 960                 TALLOC_FREE(cmd);
 961                 if (ret != 0 && lp_preexec_close(snum)) {
 962                         DEBUG(1,("preexec gave %d - failing connection\n",
 963                                  ret));
 964                         *pstatus = NT_STATUS_ACCESS_DENIED;
 965                         goto err_root_exit;
 966                 }
 967         }
 968
 969         /*
 970          * If widelinks are disallowed we need to canonicalise the connect
 971          * path here to ensure we don't have any symlinks in the
 972          * connectpath. We will be checking all paths on this connection are
 973          * below this directory. We must do this after the VFS init as we
 974          * depend on the realpath() pointer in the vfs table. JRA.
 975          */
 976         if (!lp_safe_widelinks(snum)) {
 977                 if (!canonicalize_connect_path(conn)) {
 978                         DEBUG(0, ("canonicalize_connect_path failed "
 979                         "for service %s, path %s\n",
 980                                 lp_servicename(snum),
 981                                 conn->connectpath));
 982                         *pstatus = NT_STATUS_BAD_NETWORK_NAME;
 983                         goto err_root_exit;
 984                 }
 985         }
 986
 987 #ifdef WITH_FAKE_KASERVER
 988         if (lp_afs_share(snum)) {
 989                 afs_login(conn);
 990         }
 991 #endif
 992
 993         /* Add veto/hide lists */
 994         if (!IS_IPC(conn) && !IS_PRINT(conn)) {
 995                 set_namearray( &conn->veto_list, lp_veto_files(snum));
 996                 set_namearray( &conn->hide_list, lp_hide_files(snum));
 997                 set_namearray( &conn->veto_oplock_list, lp_veto_oplocks(snum));
 998                 set_namearray( &conn->aio_write_behind_list,
 999                                 lp_aio_write_behind(snum));
1000         }
1001
1002         /* Invoke VFS make connection hook - do this before the VFS_STAT call
1003            to allow any filesystems needing user credentials to initialize
1004            themselves. */
1005
1006         if (SMB_VFS_CONNECT(conn, lp_servicename(snum),
1007                             conn->server_info->unix_name) < 0) {
1008                 DEBUG(0,("make_connection: VFS make connection failed!\n"));
1009                 *pstatus = NT_STATUS_UNSUCCESSFUL;
1010                 goto err_root_exit;
1011         }
1012
1013         /* Any error exit after here needs to call the disconnect hook. */
1014         on_err_call_dis_hook = true;
1015
1016         status = create_synthetic_smb_fname(talloc_tos(), conn->connectpath,
1017                                             NULL, NULL, &smb_fname_cpath);
1018         if (!NT_STATUS_IS_OK(status)) {
1019                 *pstatus = status;
1020                 goto err_root_exit;
1021         }
1022
1023         /* win2000 does not check the permissions on the directory
1024            during the tree connect, instead relying on permission
1025            check during individual operations. To match this behaviour
1026            I have disabled this chdir check (tridge) */
1027         /* the alternative is just to check the directory exists */
1028         if ((ret = SMB_VFS_STAT(conn, smb_fname_cpath)) != 0 ||
1029             !S_ISDIR(smb_fname_cpath->st.st_ex_mode)) {
1030                 if (ret == 0 && !S_ISDIR(smb_fname_cpath->st.st_ex_mode)) {
1031                         DEBUG(0,("'%s' is not a directory, when connecting to "
1032                                  "[%s]\n", conn->connectpath,
1033                                  lp_servicename(snum)));
1034                 } else {
1035                         DEBUG(0,("'%s' does not exist or permission denied "
1036                                  "when connecting to [%s] Error was %s\n",
1037                                  conn->connectpath, lp_servicename(snum),
1038                                  strerror(errno) ));
1039                 }
1040                 *pstatus = NT_STATUS_BAD_NETWORK_NAME;
1041                 goto err_root_exit;
1042         }
1043
1044         string_set(&conn->origpath,conn->connectpath);
1045
1046 #if SOFTLINK_OPTIMISATION
1047         /* resolve any soft links early if possible */
1048         if (vfs_ChDir(conn,conn->connectpath) == 0) {
1049                 TALLOC_CTX *ctx = talloc_tos();
1050                 char *s = vfs_GetWd(ctx,s);
1051                 if (!s) {
1052                         *status = map_nt_error_from_unix(errno);
1053                         goto err_root_exit;
1054                 }
1055                 if (!set_conn_connectpath(conn,s)) {
1056                         *status = NT_STATUS_NO_MEMORY;
1057                         goto err_root_exit;
1058                 }
1059                 vfs_ChDir(conn,conn->connectpath);
1060         }
1061 #endif
1062
1063         /* Figure out the characteristics of the underlying filesystem. This
1064          * assumes that all the filesystem mounted withing a share path have
1065          * the same characteristics, which is likely but not guaranteed.
1066          */
1067
1068         conn->fs_capabilities = SMB_VFS_FS_CAPABILITIES(conn, &conn->ts_res);
1069
1070         /*
1071          * Print out the 'connected as' stuff here as we need
1072          * to know the effective uid and gid we will be using
1073          * (at least initially).
1074          */
1075
1076         if( DEBUGLVL( IS_IPC(conn) ? 3 : 1 ) ) {
1077                 dbgtext( "%s (%s) ", get_remote_machine_name(),
1078                          conn->client_address );
1079                 dbgtext( "%s", srv_is_signing_active(smbd_server_conn) ? "signed " : "");
1080                 dbgtext( "connect to service %s ", lp_servicename(snum) );
1081                 dbgtext( "initially as user %s ",
1082                          conn->server_info->unix_name );
1083                 dbgtext( "(uid=%d, gid=%d) ", (int)geteuid(), (int)getegid() );
1084                 dbgtext( "(pid %d)\n", (int)sys_getpid() );
1085         }
1086
1087         /* we've finished with the user stuff - go back to root */
1088         change_to_root_user();
1089         return(conn);
1090
1091   err_root_exit:
1092         TALLOC_FREE(smb_fname_cpath);
1093         change_to_root_user();
1094         if (on_err_call_dis_hook) {
1095                 /* Call VFS disconnect hook */
1096                 SMB_VFS_DISCONNECT(conn);
1097         }
1098         yield_connection(conn, lp_servicename(snum));
1099         conn_free(conn);
1100         return NULL;
1101 }
1102
1103 /****************************************************************************
1104  Make a connection to a service.
1105  *
1106  * @param service
1107 ****************************************************************************/
1108
1109 connection_struct *make_connection(struct smbd_server_connection *sconn,
1110                                    const char *service_in, DATA_BLOB password,
1111                                    const char *pdev, uint16 vuid,
1112                                    NTSTATUS *status)
1113 {
1114         uid_t euid;
1115         user_struct *vuser = NULL;
1116         fstring service;
1117         fstring dev;
1118         int snum = -1;
1119         char addr[INET6_ADDRSTRLEN];
1120
1121         fstrcpy(dev, pdev);
1122
1123         /* This must ONLY BE CALLED AS ROOT. As it exits this function as
1124          * root. */
1125         if (!non_root_mode() && (euid = geteuid()) != 0) {
1126                 DEBUG(0,("make_connection: PANIC ERROR. Called as nonroot "
1127                          "(%u)\n", (unsigned int)euid ));
1128                 smb_panic("make_connection: PANIC ERROR. Called as nonroot\n");
1129         }
1130
1131         if (conn_num_open(sconn) > 2047) {
1132                 *status = NT_STATUS_INSUFF_SERVER_RESOURCES;
1133                 return NULL;
1134         }
1135
1136         if(lp_security() != SEC_SHARE) {
1137                 vuser = get_valid_user_struct(sconn, vuid);
1138                 if (!vuser) {
1139                         DEBUG(1,("make_connection: refusing to connect with "
1140                                  "no session setup\n"));
1141                         *status = NT_STATUS_ACCESS_DENIED;
1142                         return NULL;
1143                 }
1144         }
1145
1146         /* Logic to try and connect to the correct [homes] share, preferably
1147            without too many getpwnam() lookups.  This is particulary nasty for
1148            winbind usernames, where the share name isn't the same as unix
1149            username.
1150
1151            The snum of the homes share is stored on the vuser at session setup
1152            time.
1153         */
1154
1155         if (strequal(service_in,HOMES_NAME)) {
1156                 if(lp_security() != SEC_SHARE) {
1157                         DATA_BLOB no_pw = data_blob_null;
1158                         if (vuser->homes_snum == -1) {
1159                                 DEBUG(2, ("[homes] share not available for "
1160                                           "this user because it was not found "
1161                                           "or created at session setup "
1162                                           "time\n"));
1163                                 *status = NT_STATUS_BAD_NETWORK_NAME;
1164                                 return NULL;
1165                         }
1166                         DEBUG(5, ("making a connection to [homes] service "
1167                                   "created at session setup time\n"));
1168                         return make_connection_snum(sconn,
1169                                                     vuser->homes_snum,
1170                                                     vuser, no_pw,
1171                                                     dev, status);
1172                 } else {
1173                         /* Security = share. Try with
1174                          * current_user_info.smb_name as the username.  */
1175                         if (*current_user_info.smb_name) {
1176                                 fstring unix_username;
1177                                 fstrcpy(unix_username,
1178                                         current_user_info.smb_name);
1179                                 map_username(sconn, unix_username);
1180                                 snum = find_service(unix_username);
1181                         }
1182                         if (snum != -1) {
1183                                 DEBUG(5, ("making a connection to 'homes' "
1184                                           "service %s based on "
1185                                           "security=share\n", service_in));
1186                                 return make_connection_snum(sconn,
1187                                                             snum, NULL,
1188                                                             password,
1189                                                             dev, status);
1190                         }
1191                 }
1192         } else if ((lp_security() != SEC_SHARE) && (vuser->homes_snum != -1)
1193                    && strequal(service_in,
1194                                lp_servicename(vuser->homes_snum))) {
1195                 DATA_BLOB no_pw = data_blob_null;
1196                 DEBUG(5, ("making a connection to 'homes' service [%s] "
1197                           "created at session setup time\n", service_in));
1198                 return make_connection_snum(sconn,
1199                                             vuser->homes_snum,
1200                                             vuser, no_pw,
1201                                             dev, status);
1202         }
1203
1204         fstrcpy(service, service_in);
1205
1206         strlower_m(service);
1207
1208         snum = find_service(service);
1209
1210         if (snum < 0) {
1211                 if (strequal(service,"IPC$") ||
1212                     (lp_enable_asu_support() && strequal(service,"ADMIN$"))) {
1213                         DEBUG(3,("refusing IPC connection to %s\n", service));
1214                         *status = NT_STATUS_ACCESS_DENIED;
1215                         return NULL;
1216                 }
1217
1218                 DEBUG(3,("%s (%s) couldn't find service %s\n",
1219                         get_remote_machine_name(),
1220                         client_addr(get_client_fd(),addr,sizeof(addr)),
1221                         service));
1222                 *status = NT_STATUS_BAD_NETWORK_NAME;
1223                 return NULL;
1224         }
1225
1226         /* Handle non-Dfs clients attempting connections to msdfs proxy */
1227         if (lp_host_msdfs() && (*lp_msdfs_proxy(snum) != '\0'))  {
1228                 DEBUG(3, ("refusing connection to dfs proxy share '%s' "
1229                           "(pointing to %s)\n",
1230                         service, lp_msdfs_proxy(snum)));
1231                 *status = NT_STATUS_BAD_NETWORK_NAME;
1232                 return NULL;
1233         }
1234
1235         DEBUG(5, ("making a connection to 'normal' service %s\n", service));
1236
1237         return make_connection_snum(sconn, snum, vuser,
1238                                     password,
1239                                     dev, status);
1240 }
1241
1242 /****************************************************************************
1243  Close a cnum.
1244 ****************************************************************************/
1245
1246 void close_cnum(connection_struct *conn, uint16 vuid)
1247 {
1248         file_close_conn(conn);
1249
1250         if (!IS_IPC(conn)) {
1251                 dptr_closecnum(conn);
1252         }
1253
1254         change_to_root_user();
1255
1256         DEBUG(IS_IPC(conn)?3:1, ("%s (%s) closed connection to service %s\n",
1257                                  get_remote_machine_name(),
1258                                  conn->client_address,
1259                                  lp_servicename(SNUM(conn))));
1260
1261         /* Call VFS disconnect hook */
1262         SMB_VFS_DISCONNECT(conn);
1263
1264         yield_connection(conn, lp_servicename(SNUM(conn)));
1265
1266         /* make sure we leave the directory available for unmount */
1267         vfs_ChDir(conn, "/");
1268
1269         /* execute any "postexec = " line */
1270         if (*lp_postexec(SNUM(conn)) &&
1271             change_to_user(conn, vuid))  {
1272                 char *cmd = talloc_sub_advanced(talloc_tos(),
1273                                         lp_servicename(SNUM(conn)),
1274                                         conn->server_info->unix_name,
1275                                         conn->connectpath,
1276                                         conn->server_info->utok.gid,
1277                                         conn->server_info->sanitized_username,
1278                                         pdb_get_domain(conn->server_info->sam_account),
1279                                         lp_postexec(SNUM(conn)));
1280                 smbrun(cmd,NULL);
1281                 TALLOC_FREE(cmd);
1282                 change_to_root_user();
1283         }
1284
1285         change_to_root_user();
1286         /* execute any "root postexec = " line */
1287         if (*lp_rootpostexec(SNUM(conn)))  {
1288                 char *cmd = talloc_sub_advanced(talloc_tos(),
1289                                         lp_servicename(SNUM(conn)),
1290                                         conn->server_info->unix_name,
1291                                         conn->connectpath,
1292                                         conn->server_info->utok.gid,
1293                                         conn->server_info->sanitized_username,
1294                                         pdb_get_domain(conn->server_info->sam_account),
1295                                         lp_rootpostexec(SNUM(conn)));
1296                 smbrun(cmd,NULL);
1297                 TALLOC_FREE(cmd);
1298         }
1299
1300         conn_free(conn);
1301 }