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 #include "../librpc/gen_ndr/netlogon.h"
  23
  24 extern userdom_struct current_user_info;
  25
  26 static bool canonicalize_connect_path(connection_struct *conn)
  27 {
  28 #ifdef REALPATH_TAKES_NULL
  29         bool ret;
  30         char *resolved_name = SMB_VFS_REALPATH(conn,conn->connectpath,NULL);
  31         if (!resolved_name) {
  32                 return false;
  33         }
  34         ret = set_conn_connectpath(conn,resolved_name);
  35         SAFE_FREE(resolved_name);
  36         return ret;
  37 #else
  38         char resolved_name_buf[PATH_MAX+1];
  39         char *resolved_name = SMB_VFS_REALPATH(conn,conn->connectpath,resolved_name_buf);
  40         if (!resolved_name) {
  41                 return false;
  42         }
  43         return set_conn_connectpath(conn,resolved_name);
  44 #endif /* REALPATH_TAKES_NULL */
  45 }
  46
  47 /****************************************************************************
  48  Ensure when setting connectpath it is a canonicalized (no ./ // or ../)
  49  absolute path stating in / and not ending in /.
  50  Observent people will notice a similarity between this and check_path_syntax :-).
  51 ****************************************************************************/
  52
  53 bool set_conn_connectpath(connection_struct *conn, const char *connectpath)
  54 {
  55         char *destname;
  56         char *d;
  57         const char *s = connectpath;
  58         bool start_of_name_component = true;
  59
  60         if (connectpath == NULL || connectpath[0] == '\0') {
  61                 return false;
  62         }
  63
  64         /* Allocate for strlen + '\0' + possible leading '/' */
  65         destname = (char *)SMB_MALLOC(strlen(connectpath) + 2);
  66         if (!destname) {
  67                 return false;
  68         }
  69         d = destname;
  70
  71         *d++ = '/'; /* Always start with root. */
  72
  73         while (*s) {
  74                 if (*s == '/') {
  75                         /* Eat multiple '/' */
  76                         while (*s == '/') {
  77                                 s++;
  78                         }
  79                         if ((d > destname + 1) && (*s != '\0')) {
  80                                 *d++ = '/';
  81                         }
  82                         start_of_name_component = True;
  83                         continue;
  84                 }
  85
  86                 if (start_of_name_component) {
  87                         if ((s[0] == '.') && (s[1] == '.') && (s[2] == '/' || s[2] == '\0')) {
  88                                 /* Uh oh - "/../" or "/..\0" ! */
  89
  90                                 /* Go past the ../ or .. */
  91                                 if (s[2] == '/') {
  92                                         s += 3;
  93                                 } else {
  94                                         s += 2; /* Go past the .. */
  95                                 }
  96
  97                                 /* If  we just added a '/' - delete it */
  98                                 if ((d > destname) && (*(d-1) == '/')) {
  99                                         *(d-1) = '\0';
 100                                         d--;
 101                                 }
 102
 103                                 /* Are we at the start ? Can't go back further if so. */
 104                                 if (d <= destname) {
 105                                         *d++ = '/'; /* Can't delete root */
 106                                         continue;
 107                                 }
 108                                 /* Go back one level... */
 109                                 /* Decrement d first as d points to the *next* char to write into. */
 110                                 for (d--; d > destname; d--) {
 111                                         if (*d == '/') {
 112                                                 break;
 113                                         }
 114                                 }
 115                                 /* We're still at the start of a name component, just the previous one. */
 116                                 continue;
 117                         } else if ((s[0] == '.') && ((s[1] == '\0') || s[1] == '/')) {
 118                                 /* Component of pathname can't be "." only - skip the '.' . */
 119                                 if (s[1] == '/') {
 120                                         s += 2;
 121                                 } else {
 122                                         s++;
 123                                 }
 124                                 continue;
 125                         }
 126                 }
 127
 128                 if (!(*s & 0x80)) {
 129                         *d++ = *s++;
 130                 } else {
 131                         size_t siz;
 132                         /* Get the size of the next MB character. */
 133                         next_codepoint(s,&siz);
 134                         switch(siz) {
 135                                 case 5:
 136                                         *d++ = *s++;
 137                                         /*fall through*/
 138                                 case 4:
 139                                         *d++ = *s++;
 140                                         /*fall through*/
 141                                 case 3:
 142                                         *d++ = *s++;
 143                                         /*fall through*/
 144                                 case 2:
 145                                         *d++ = *s++;
 146                                         /*fall through*/
 147                                 case 1:
 148                                         *d++ = *s++;
 149                                         break;
 150                                 default:
 151                                         break;
 152                         }
 153                 }
 154                 start_of_name_component = false;
 155         }
 156         *d = '\0';
 157
 158         /* And must not end in '/' */
 159         if (d > destname + 1 && (*(d-1) == '/')) {
 160                 *(d-1) = '\0';
 161         }
 162
 163         DEBUG(10,("set_conn_connectpath: service %s, connectpath = %s\n",
 164                 lp_servicename(SNUM(conn)), destname ));
 165
 166         string_set(&conn->connectpath, destname);
 167         SAFE_FREE(destname);
 168         return true;
 169 }
 170
 171 /****************************************************************************
 172  Load parameters specific to a connection/service.
 173 ****************************************************************************/
 174
 175 bool set_current_service(connection_struct *conn, uint16 flags, bool do_chdir)
 176 {
 177         int snum;
 178
 179         if (!conn)  {
 180                 last_conn = NULL;
 181                 return(False);
 182         }
 183
 184         conn->lastused_count++;
 185
 186         snum = SNUM(conn);
 187
 188         if (do_chdir &&
 189             vfs_ChDir(conn,conn->connectpath) != 0 &&
 190             vfs_ChDir(conn,conn->origpath) != 0) {
 191                 DEBUG(((errno!=EACCES)?0:3),("chdir (%s) failed, reason: %s\n",
 192                          conn->connectpath, strerror(errno)));
 193                 return(False);
 194         }
 195
 196         if ((conn == last_conn) && (last_flags == flags)) {
 197                 return(True);
 198         }
 199
 200         last_conn = conn;
 201         last_flags = flags;
 202
 203         /* Obey the client case sensitivity requests - only for clients that support it. */
 204         switch (lp_casesensitive(snum)) {
 205                 case Auto:
 206                         {
 207                                 /* We need this uglyness due to DOS/Win9x clients that lie about case insensitivity. */
 208                                 enum remote_arch_types ra_type = get_remote_arch();
 209                                 if ((ra_type != RA_SAMBA) && (ra_type != RA_CIFSFS)) {
 210                                         /* Client can't support per-packet case sensitive pathnames. */
 211                                         conn->case_sensitive = False;
 212                                 } else {
 213                                         conn->case_sensitive = !(flags & FLAG_CASELESS_PATHNAMES);
 214                                 }
 215                         }
 216                         break;
 217                 case True:
 218                         conn->case_sensitive = True;
 219                         break;
 220                 default:
 221                         conn->case_sensitive = False;
 222                         break;
 223         }
 224         return(True);
 225 }
 226
 227 static int load_registry_service(const char *servicename)
 228 {
 229         if (!lp_registry_shares()) {
 230                 return -1;
 231         }
 232
 233         if ((servicename == NULL) || (*servicename == '\0')) {
 234                 return -1;
 235         }
 236
 237         if (strequal(servicename, GLOBAL_NAME)) {
 238                 return -2;
 239         }
 240
 241         if (!process_registry_service(servicename)) {
 242                 return -1;
 243         }
 244
 245         return lp_servicenumber(servicename);
 246 }
 247
 248 void load_registry_shares(void)
 249 {
 250         DEBUG(8, ("load_registry_shares()\n"));
 251         if (!lp_registry_shares()) {
 252                 return;
 253         }
 254
 255         process_registry_shares();
 256
 257         return;
 258 }
 259
 260 /****************************************************************************
 261  Add a home service. Returns the new service number or -1 if fail.
 262 ****************************************************************************/
 263
 264 int add_home_service(const char *service, const char *username, const char *homedir)
 265 {
 266         int iHomeService;
 267
 268         if (!service || !homedir || homedir[0] == '\0')
 269                 return -1;
 270
 271         if ((iHomeService = lp_servicenumber(HOMES_NAME)) < 0) {
 272                 if ((iHomeService = load_registry_service(HOMES_NAME)) < 0) {
 273                         return -1;
 274                 }
 275         }
 276
 277         /*
 278          * If this is a winbindd provided username, remove
 279          * the domain component before adding the service.
 280          * Log a warning if the "path=" parameter does not
 281          * include any macros.
 282          */
 283
 284         {
 285                 const char *p = strchr(service,*lp_winbind_separator());
 286
 287                 /* We only want the 'user' part of the string */
 288                 if (p) {
 289                         service = p + 1;
 290                 }
 291         }
 292
 293         if (!lp_add_home(service, iHomeService, username, homedir)) {
 294                 return -1;
 295         }
 296
 297         return lp_servicenumber(service);
 298
 299 }
 300
 301 /**
 302  * Find a service entry.
 303  *
 304  * @param service is modified (to canonical form??)
 305  **/
 306
 307 int find_service(fstring service)
 308 {
 309         int iService;
 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(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 >= 0) {
 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 server_sock, int snum, fstring dev)
 428 {
 429         if (!lp_snum_ok(snum) ||
 430             !check_access(server_sock,
 431                           lp_hostsallow(snum), lp_hostsdeny(snum))) {
 432                 return NT_STATUS_ACCESS_DENIED;
 433         }
 434
 435         if (dev[0] == '?' || !dev[0]) {
 436                 if (lp_print_ok(snum)) {
 437                         fstrcpy(dev,"LPT1:");
 438                 } else if (strequal(lp_fstype(snum), "IPC")) {
 439                         fstrcpy(dev, "IPC");
 440                 } else {
 441                         fstrcpy(dev,"A:");
 442                 }
 443         }
 444
 445         strupper_m(dev);
 446
 447         if (lp_print_ok(snum)) {
 448                 if (!strequal(dev, "LPT1:")) {
 449                         return NT_STATUS_BAD_DEVICE_TYPE;
 450                 }
 451         } else if (strequal(lp_fstype(snum), "IPC")) {
 452                 if (!strequal(dev, "IPC")) {
 453                         return NT_STATUS_BAD_DEVICE_TYPE;
 454                 }
 455         } else if (!strequal(dev, "A:")) {
 456                 return NT_STATUS_BAD_DEVICE_TYPE;
 457         }
 458
 459         /* Behave as a printer if we are supposed to */
 460         if (lp_print_ok(snum) && (strcmp(dev, "A:") == 0)) {
 461                 fstrcpy(dev, "LPT1:");
 462         }
 463
 464         return NT_STATUS_OK;
 465 }
 466
 467 /*
 468  * Go through lookup_name etc to find the force'd group.
 469  *
 470  * Create a new token from src_token, replacing the primary group sid with the
 471  * one found.
 472  */
 473
 474 static NTSTATUS find_forced_group(bool force_user,
 475                                   int snum, const char *username,
 476                                   struct dom_sid *pgroup_sid,
 477                                   gid_t *pgid)
 478 {
 479         NTSTATUS result = NT_STATUS_NO_SUCH_GROUP;
 480         TALLOC_CTX *frame = talloc_stackframe();
 481         struct dom_sid group_sid;
 482         enum lsa_SidType type;
 483         char *groupname;
 484         bool user_must_be_member = False;
 485         gid_t gid;
 486
 487         groupname = talloc_strdup(talloc_tos(), lp_force_group(snum));
 488         if (groupname == NULL) {
 489                 DEBUG(1, ("talloc_strdup failed\n"));
 490                 result = NT_STATUS_NO_MEMORY;
 491                 goto done;
 492         }
 493
 494         if (groupname[0] == '+') {
 495                 user_must_be_member = True;
 496                 groupname += 1;
 497         }
 498
 499         groupname = talloc_string_sub(talloc_tos(), groupname,
 500                                       "%S", lp_servicename(snum));
 501         if (groupname == NULL) {
 502                 DEBUG(1, ("talloc_string_sub failed\n"));
 503                 result = NT_STATUS_NO_MEMORY;
 504                 goto done;
 505         }
 506
 507         if (!lookup_name_smbconf(talloc_tos(), groupname,
 508                          LOOKUP_NAME_ALL|LOOKUP_NAME_GROUP,
 509                          NULL, NULL, &group_sid, &type)) {
 510                 DEBUG(10, ("lookup_name_smbconf(%s) failed\n",
 511                            groupname));
 512                 goto done;
 513         }
 514
 515         if ((type != SID_NAME_DOM_GRP) && (type != SID_NAME_ALIAS) &&
 516             (type != SID_NAME_WKN_GRP)) {
 517                 DEBUG(10, ("%s is a %s, not a group\n", groupname,
 518                            sid_type_lookup(type)));
 519                 goto done;
 520         }
 521
 522         if (!sid_to_gid(&group_sid, &gid)) {
 523                 DEBUG(10, ("sid_to_gid(%s) for %s failed\n",
 524                            sid_string_dbg(&group_sid), groupname));
 525                 goto done;
 526         }
 527
 528         /*
 529          * If the user has been forced and the forced group starts with a '+',
 530          * then we only set the group to be the forced group if the forced
 531          * user is a member of that group.  Otherwise, the meaning of the '+'
 532          * would be ignored.
 533          */
 534
 535         if (force_user && user_must_be_member) {
 536                 if (user_in_group_sid(username, &group_sid)) {
 537                         sid_copy(pgroup_sid, &group_sid);
 538                         *pgid = gid;
 539                         DEBUG(3,("Forced group %s for member %s\n",
 540                                  groupname, username));
 541                 } else {
 542                         DEBUG(0,("find_forced_group: forced user %s is not a member "
 543                                 "of forced group %s. Disallowing access.\n",
 544                                 username, groupname ));
 545                         result = NT_STATUS_MEMBER_NOT_IN_GROUP;
 546                         goto done;
 547                 }
 548         } else {
 549                 sid_copy(pgroup_sid, &group_sid);
 550                 *pgid = gid;
 551                 DEBUG(3,("Forced group %s\n", groupname));
 552         }
 553
 554         result = NT_STATUS_OK;
 555  done:
 556         TALLOC_FREE(frame);
 557         return result;
 558 }
 559
 560 /****************************************************************************
 561   Create an auth_serversupplied_info structure for a connection_struct
 562 ****************************************************************************/
 563
 564 static NTSTATUS create_connection_server_info(struct smbd_server_connection *sconn,
 565                                               TALLOC_CTX *mem_ctx, int snum,
 566                                               struct auth_serversupplied_info *vuid_serverinfo,
 567                                               DATA_BLOB password,
 568                                               struct auth_serversupplied_info **presult)
 569 {
 570         if (lp_guest_only(snum)) {
 571                 return make_server_info_guest(mem_ctx, presult);
 572         }
 573
 574         if (vuid_serverinfo != NULL) {
 575
 576                 struct auth_serversupplied_info *result;
 577
 578                 /*
 579                  * This is the normal security != share case where we have a
 580                  * valid vuid from the session setup.                 */
 581
 582                 if (vuid_serverinfo->guest) {
 583                         if (!lp_guest_ok(snum)) {
 584                                 DEBUG(2, ("guest user (from session setup) "
 585                                           "not permitted to access this share "
 586                                           "(%s)\n", lp_servicename(snum)));
 587                                 return NT_STATUS_ACCESS_DENIED;
 588                         }
 589                 } else {
 590                         if (!user_ok_token(vuid_serverinfo->unix_name,
 591                                            vuid_serverinfo->info3->base.domain.string,
 592                                            vuid_serverinfo->ptok, snum)) {
 593                                 DEBUG(2, ("user '%s' (from session setup) not "
 594                                           "permitted to access this share "
 595                                           "(%s)\n",
 596                                           vuid_serverinfo->unix_name,
 597                                           lp_servicename(snum)));
 598                                 return NT_STATUS_ACCESS_DENIED;
 599                         }
 600                 }
 601
 602                 result = copy_serverinfo(mem_ctx, vuid_serverinfo);
 603                 if (result == NULL) {
 604                         return NT_STATUS_NO_MEMORY;
 605                 }
 606
 607                 *presult = result;
 608                 return NT_STATUS_OK;
 609         }
 610
 611         if (lp_security() == SEC_SHARE) {
 612
 613                 fstring user;
 614                 bool guest;
 615
 616                 /* add the sharename as a possible user name if we
 617                    are in share mode security */
 618
 619                 add_session_user(sconn, lp_servicename(snum));
 620
 621                 /* shall we let them in? */
 622
 623                 if (!authorise_login(sconn, snum,user,password,&guest)) {
 624                         DEBUG( 2, ( "Invalid username/password for [%s]\n",
 625                                     lp_servicename(snum)) );
 626                         return NT_STATUS_WRONG_PASSWORD;
 627                 }
 628
 629                 return make_serverinfo_from_username(mem_ctx, user, guest,
 630                                                      presult);
 631         }
 632
 633         DEBUG(0, ("invalid VUID (vuser) but not in security=share\n"));
 634         return NT_STATUS_ACCESS_DENIED;
 635 }
 636
 637
 638 /****************************************************************************
 639   Make a connection, given the snum to connect to, and the vuser of the
 640   connecting user if appropriate.
 641 ****************************************************************************/
 642
 643 connection_struct *make_connection_snum(struct smbd_server_connection *sconn,
 644                                         int snum, user_struct *vuser,
 645                                         DATA_BLOB password,
 646                                         const char *pdev,
 647                                         NTSTATUS *pstatus)
 648 {
 649         connection_struct *conn = NULL;
 650         struct smb_filename *smb_fname_cpath = NULL;
 651         fstring dev;
 652         int ret;
 653         bool on_err_call_dis_hook = false;
 654         bool claimed_connection = false;
 655         uid_t effuid;
 656         gid_t effgid;
 657         NTSTATUS status;
 658
 659         fstrcpy(dev, pdev);
 660
 661         *pstatus = share_sanity_checks(sconn->sock, snum, dev);
 662         if (NT_STATUS_IS_ERR(*pstatus)) {
 663                 goto err_root_exit;
 664         }
 665
 666         conn = conn_new(sconn);
 667         if (!conn) {
 668                 DEBUG(0,("Couldn't find free connection.\n"));
 669                 *pstatus = NT_STATUS_INSUFFICIENT_RESOURCES;
 670                 goto err_root_exit;
 671         }
 672
 673         conn->params->service = snum;
 674
 675         status = create_connection_server_info(sconn,
 676                 conn, snum, vuser ? vuser->server_info : NULL, password,
 677                 &conn->server_info);
 678
 679         if (!NT_STATUS_IS_OK(status)) {
 680                 DEBUG(1, ("create_connection_server_info failed: %s\n",
 681                           nt_errstr(status)));
 682                 *pstatus = status;
 683                 goto err_root_exit;
 684         }
 685
 686         if ((lp_guest_only(snum)) || (lp_security() == SEC_SHARE)) {
 687                 conn->force_user = true;
 688         }
 689
 690         add_session_user(sconn, conn->server_info->unix_name);
 691
 692         conn->num_files_open = 0;
 693         conn->lastused = conn->lastused_count = time(NULL);
 694         conn->used = True;
 695         conn->printer = (strncmp(dev,"LPT",3) == 0);
 696         conn->ipc = ( (strncmp(dev,"IPC",3) == 0) ||
 697                       ( lp_enable_asu_support() && strequal(dev,"ADMIN$")) );
 698
 699         /* Case options for the share. */
 700         if (lp_casesensitive(snum) == Auto) {
 701                 /* We will be setting this per packet. Set to be case
 702                  * insensitive for now. */
 703                 conn->case_sensitive = False;
 704         } else {
 705                 conn->case_sensitive = (bool)lp_casesensitive(snum);
 706         }
 707
 708         conn->case_preserve = lp_preservecase(snum);
 709         conn->short_case_preserve = lp_shortpreservecase(snum);
 710
 711         conn->encrypt_level = lp_smb_encrypt(snum);
 712
 713         conn->veto_list = NULL;
 714         conn->hide_list = NULL;
 715         conn->veto_oplock_list = NULL;
 716         conn->aio_write_behind_list = NULL;
 717
 718         conn->read_only = lp_readonly(SNUM(conn));
 719
 720         if (*lp_force_user(snum)) {
 721
 722                 /*
 723                  * Replace conn->server_info with a completely faked up one
 724                  * from the username we are forced into :-)
 725                  */
 726
 727                 char *fuser;
 728                 struct auth_serversupplied_info *forced_serverinfo;
 729
 730                 fuser = talloc_string_sub(conn, lp_force_user(snum), "%S",
 731                                           lp_servicename(snum));
 732                 if (fuser == NULL) {
 733                         *pstatus = NT_STATUS_NO_MEMORY;
 734                         goto err_root_exit;
 735                 }
 736
 737                 status = make_serverinfo_from_username(
 738                         conn, fuser, conn->server_info->guest,
 739                         &forced_serverinfo);
 740                 if (!NT_STATUS_IS_OK(status)) {
 741                         *pstatus = status;
 742                         goto err_root_exit;
 743                 }
 744
 745                 TALLOC_FREE(conn->server_info);
 746                 conn->server_info = forced_serverinfo;
 747
 748                 conn->force_user = True;
 749                 DEBUG(3,("Forced user %s\n", fuser));
 750         }
 751
 752         /*
 753          * If force group is true, then override
 754          * any groupid stored for the connecting user.
 755          */
 756
 757         if (*lp_force_group(snum)) {
 758
 759                 status = find_forced_group(
 760                         conn->force_user, snum, conn->server_info->unix_name,
 761                         &conn->server_info->ptok->user_sids[1],
 762                         &conn->server_info->utok.gid);
 763
 764                 if (!NT_STATUS_IS_OK(status)) {
 765                         *pstatus = status;
 766                         goto err_root_exit;
 767                 }
 768
 769                 /*
 770                  * We need to cache this gid, to use within
 771                  * change_to_user() separately from the conn->server_info
 772                  * struct. We only use conn->server_info directly if
 773                  * "force_user" was set.
 774                  */
 775                 conn->force_group_gid = conn->server_info->utok.gid;
 776         }
 777
 778         conn->vuid = (vuser != NULL) ? vuser->vuid : UID_FIELD_INVALID;
 779
 780         {
 781                 char *s = talloc_sub_advanced(talloc_tos(),
 782                                         lp_servicename(SNUM(conn)),
 783                                         conn->server_info->unix_name,
 784                                         conn->connectpath,
 785                                         conn->server_info->utok.gid,
 786                                         conn->server_info->sanitized_username,
 787                                         conn->server_info->info3->base.domain.string,
 788                                         lp_pathname(snum));
 789                 if (!s) {
 790                         *pstatus = NT_STATUS_NO_MEMORY;
 791                         goto err_root_exit;
 792                 }
 793
 794                 if (!set_conn_connectpath(conn,s)) {
 795                         TALLOC_FREE(s);
 796                         *pstatus = NT_STATUS_NO_MEMORY;
 797                         goto err_root_exit;
 798                 }
 799                 DEBUG(3,("Connect path is '%s' for service [%s]\n",s,
 800                          lp_servicename(snum)));
 801                 TALLOC_FREE(s);
 802         }
 803
 804         /*
 805          * New code to check if there's a share security descripter
 806          * added from NT server manager. This is done after the
 807          * smb.conf checks are done as we need a uid and token. JRA.
 808          *
 809          */
 810
 811         {
 812                 bool can_write = False;
 813
 814                 can_write = share_access_check(conn->server_info->ptok,
 815                                                lp_servicename(snum),
 816                                                FILE_WRITE_DATA);
 817
 818                 if (!can_write) {
 819                         if (!share_access_check(conn->server_info->ptok,
 820                                                 lp_servicename(snum),
 821                                                 FILE_READ_DATA)) {
 822                                 /* No access, read or write. */
 823                                 DEBUG(0,("make_connection: connection to %s "
 824                                          "denied due to security "
 825                                          "descriptor.\n",
 826                                           lp_servicename(snum)));
 827                                 *pstatus = NT_STATUS_ACCESS_DENIED;
 828                                 goto err_root_exit;
 829                         } else {
 830                                 conn->read_only = True;
 831                         }
 832                 }
 833         }
 834         /* Initialise VFS function pointers */
 835
 836         if (!smbd_vfs_init(conn)) {
 837                 DEBUG(0, ("vfs_init failed for service %s\n",
 838                           lp_servicename(snum)));
 839                 *pstatus = NT_STATUS_BAD_NETWORK_NAME;
 840                 goto err_root_exit;
 841         }
 842
 843 /* ROOT Activities: */
 844         /* explicitly check widelinks here so that we can correctly warn
 845          * in the logs. */
 846         widelinks_warning(snum);
 847
 848         /*
 849          * Enforce the max connections parameter.
 850          */
 851
 852         if ((lp_max_connections(snum) > 0)
 853             && (count_current_connections(lp_servicename(SNUM(conn)), True) >=
 854                 lp_max_connections(snum))) {
 855
 856                 DEBUG(1, ("Max connections (%d) exceeded for %s\n",
 857                           lp_max_connections(snum), lp_servicename(snum)));
 858                 *pstatus = NT_STATUS_INSUFFICIENT_RESOURCES;
 859                 goto err_root_exit;
 860         }
 861
 862         /*
 863          * Get us an entry in the connections db
 864          */
 865         if (!claim_connection(conn, lp_servicename(snum))) {
 866                 DEBUG(1, ("Could not store connections entry\n"));
 867                 *pstatus = NT_STATUS_INTERNAL_DB_ERROR;
 868                 goto err_root_exit;
 869         }
 870         claimed_connection = true;
 871
 872         /* Invoke VFS make connection hook - this must be the first
 873            filesystem operation that we do. */
 874
 875         if (SMB_VFS_CONNECT(conn, lp_servicename(snum),
 876                             conn->server_info->unix_name) < 0) {
 877                 DEBUG(0,("make_connection: VFS make connection failed!\n"));
 878                 *pstatus = NT_STATUS_UNSUCCESSFUL;
 879                 goto err_root_exit;
 880         }
 881
 882         /* Any error exit after here needs to call the disconnect hook. */
 883         on_err_call_dis_hook = true;
 884
 885         if ((!conn->printer) && (!conn->ipc)) {
 886                 conn->notify_ctx = notify_init(conn,
 887                                                sconn_server_id(sconn),
 888                                                sconn->msg_ctx,
 889                                                smbd_event_context(),
 890                                                conn);
 891         }
 892
 893         /*
 894          * Fix compatibility issue pointed out by Volker.
 895          * We pass the conn->connectpath to the preexec
 896          * scripts as a parameter, so attempt to canonicalize
 897          * it here before calling the preexec scripts.
 898          * We ignore errors here, as it is possible that
 899          * the conn->connectpath doesn't exist yet and
 900          * the preexec scripts will create them.
 901          */
 902
 903         (void)canonicalize_connect_path(conn);
 904
 905         /* Preexecs are done here as they might make the dir we are to ChDir
 906          * to below */
 907         /* execute any "root preexec = " line */
 908         if (*lp_rootpreexec(snum)) {
 909                 char *cmd = talloc_sub_advanced(talloc_tos(),
 910                                         lp_servicename(SNUM(conn)),
 911                                         conn->server_info->unix_name,
 912                                         conn->connectpath,
 913                                         conn->server_info->utok.gid,
 914                                         conn->server_info->sanitized_username,
 915                                         conn->server_info->info3->base.domain.string,
 916                                         lp_rootpreexec(snum));
 917                 DEBUG(5,("cmd=%s\n",cmd));
 918                 ret = smbrun(cmd,NULL);
 919                 TALLOC_FREE(cmd);
 920                 if (ret != 0 && lp_rootpreexec_close(snum)) {
 921                         DEBUG(1,("root preexec gave %d - failing "
 922                                  "connection\n", ret));
 923                         *pstatus = NT_STATUS_ACCESS_DENIED;
 924                         goto err_root_exit;
 925                 }
 926         }
 927
 928 /* USER Activites: */
 929         if (!change_to_user(conn, conn->vuid)) {
 930                 /* No point continuing if they fail the basic checks */
 931                 DEBUG(0,("Can't become connected user!\n"));
 932                 *pstatus = NT_STATUS_LOGON_FAILURE;
 933                 goto err_root_exit;
 934         }
 935
 936         effuid = geteuid();
 937         effgid = getegid();
 938
 939         /* Remember that a different vuid can connect later without these
 940          * checks... */
 941
 942         /* Preexecs are done here as they might make the dir we are to ChDir
 943          * to below */
 944
 945         /* execute any "preexec = " line */
 946         if (*lp_preexec(snum)) {
 947                 char *cmd = talloc_sub_advanced(talloc_tos(),
 948                                         lp_servicename(SNUM(conn)),
 949                                         conn->server_info->unix_name,
 950                                         conn->connectpath,
 951                                         conn->server_info->utok.gid,
 952                                         conn->server_info->sanitized_username,
 953                                         conn->server_info->info3->base.domain.string,
 954                                         lp_preexec(snum));
 955                 ret = smbrun(cmd,NULL);
 956                 TALLOC_FREE(cmd);
 957                 if (ret != 0 && lp_preexec_close(snum)) {
 958                         DEBUG(1,("preexec gave %d - failing connection\n",
 959                                  ret));
 960                         *pstatus = NT_STATUS_ACCESS_DENIED;
 961                         goto err_root_exit;
 962                 }
 963         }
 964
 965 #ifdef WITH_FAKE_KASERVER
 966         if (lp_afs_share(snum)) {
 967                 afs_login(conn);
 968         }
 969 #endif
 970
 971         /*
 972          * we've finished with the user stuff - go back to root
 973          * so the SMB_VFS_STAT call will only fail on path errors,
 974          * not permission problems.
 975          */
 976         change_to_root_user();
 977 /* ROOT Activites: */
 978
 979         /*
 980          * If widelinks are disallowed we need to canonicalise the connect
 981          * path here to ensure we don't have any symlinks in the
 982          * connectpath. We will be checking all paths on this connection are
 983          * below this directory. We must do this after the VFS init as we
 984          * depend on the realpath() pointer in the vfs table. JRA.
 985          */
 986         if (!lp_widelinks(snum)) {
 987                 if (!canonicalize_connect_path(conn)) {
 988                         DEBUG(0, ("canonicalize_connect_path failed "
 989                         "for service %s, path %s\n",
 990                                 lp_servicename(snum),
 991                                 conn->connectpath));
 992                         *pstatus = NT_STATUS_BAD_NETWORK_NAME;
 993                         goto err_root_exit;
 994                 }
 995         }
 996
 997         /* Add veto/hide lists */
 998         if (!IS_IPC(conn) && !IS_PRINT(conn)) {
 999                 set_namearray( &conn->veto_list, lp_veto_files(snum));
1000                 set_namearray( &conn->hide_list, lp_hide_files(snum));
1001                 set_namearray( &conn->veto_oplock_list, lp_veto_oplocks(snum));
1002                 set_namearray( &conn->aio_write_behind_list,
1003                                 lp_aio_write_behind(snum));
1004         }
1005         status = create_synthetic_smb_fname(talloc_tos(), conn->connectpath,
1006                                             NULL, NULL, &smb_fname_cpath);
1007         if (!NT_STATUS_IS_OK(status)) {
1008                 *pstatus = status;
1009                 goto err_root_exit;
1010         }
1011
1012         /* win2000 does not check the permissions on the directory
1013            during the tree connect, instead relying on permission
1014            check during individual operations. To match this behaviour
1015            I have disabled this chdir check (tridge) */
1016         /* the alternative is just to check the directory exists */
1017
1018         if ((ret = SMB_VFS_STAT(conn, smb_fname_cpath)) != 0 ||
1019             !S_ISDIR(smb_fname_cpath->st.st_ex_mode)) {
1020                 if (ret == 0 && !S_ISDIR(smb_fname_cpath->st.st_ex_mode)) {
1021                         DEBUG(0,("'%s' is not a directory, when connecting to "
1022                                  "[%s]\n", conn->connectpath,
1023                                  lp_servicename(snum)));
1024                 } else {
1025                         DEBUG(0,("'%s' does not exist or permission denied "
1026                                  "when connecting to [%s] Error was %s\n",
1027                                  conn->connectpath, lp_servicename(snum),
1028                                  strerror(errno) ));
1029                 }
1030                 *pstatus = NT_STATUS_BAD_NETWORK_NAME;
1031                 goto err_root_exit;
1032         }
1033         conn->base_share_dev = smb_fname_cpath->st.st_ex_dev;
1034
1035         string_set(&conn->origpath,conn->connectpath);
1036
1037         /* Figure out the characteristics of the underlying filesystem. This
1038          * assumes that all the filesystem mounted withing a share path have
1039          * the same characteristics, which is likely but not guaranteed.
1040          */
1041
1042         conn->fs_capabilities = SMB_VFS_FS_CAPABILITIES(conn, &conn->ts_res);
1043
1044         /*
1045          * Print out the 'connected as' stuff here as we need
1046          * to know the effective uid and gid we will be using
1047          * (at least initially).
1048          */
1049
1050         if( DEBUGLVL( IS_IPC(conn) ? 3 : 1 ) ) {
1051                 dbgtext( "%s (%s) ", get_remote_machine_name(),
1052                          conn->sconn->client_id.addr );
1053                 dbgtext( "%s", srv_is_signing_active(sconn) ? "signed " : "");
1054                 dbgtext( "connect to service %s ", lp_servicename(snum) );
1055                 dbgtext( "initially as user %s ",
1056                          conn->server_info->unix_name );
1057                 dbgtext( "(uid=%d, gid=%d) ", (int)effuid, (int)effgid );
1058                 dbgtext( "(pid %d)\n", (int)sys_getpid() );
1059         }
1060
1061         return(conn);
1062
1063   err_root_exit:
1064         TALLOC_FREE(smb_fname_cpath);
1065         /* We must exit this function as root. */
1066         if (geteuid() != 0) {
1067                 change_to_root_user();
1068         }
1069         if (on_err_call_dis_hook) {
1070                 /* Call VFS disconnect hook */
1071                 SMB_VFS_DISCONNECT(conn);
1072         }
1073         if (claimed_connection) {
1074                 yield_connection(conn, lp_servicename(snum));
1075         }
1076         if (conn) {
1077                 conn_free(conn);
1078         }
1079         return NULL;
1080 }
1081
1082 /****************************************************************************
1083  Make a connection to a service.
1084  *
1085  * @param service
1086 ****************************************************************************/
1087
1088 connection_struct *make_connection(struct smbd_server_connection *sconn,
1089                                    const char *service_in, DATA_BLOB password,
1090                                    const char *pdev, uint16 vuid,
1091                                    NTSTATUS *status)
1092 {
1093         uid_t euid;
1094         user_struct *vuser = NULL;
1095         fstring service;
1096         fstring dev;
1097         int snum = -1;
1098
1099         fstrcpy(dev, pdev);
1100
1101         /* This must ONLY BE CALLED AS ROOT. As it exits this function as
1102          * root. */
1103         if (!non_root_mode() && (euid = geteuid()) != 0) {
1104                 DEBUG(0,("make_connection: PANIC ERROR. Called as nonroot "
1105                          "(%u)\n", (unsigned int)euid ));
1106                 smb_panic("make_connection: PANIC ERROR. Called as nonroot\n");
1107         }
1108
1109         if (conn_num_open(sconn) > 2047) {
1110                 *status = NT_STATUS_INSUFF_SERVER_RESOURCES;
1111                 return NULL;
1112         }
1113
1114         if(lp_security() != SEC_SHARE) {
1115                 vuser = get_valid_user_struct(sconn, vuid);
1116                 if (!vuser) {
1117                         DEBUG(1,("make_connection: refusing to connect with "
1118                                  "no session setup\n"));
1119                         *status = NT_STATUS_ACCESS_DENIED;
1120                         return NULL;
1121                 }
1122         }
1123
1124         /* Logic to try and connect to the correct [homes] share, preferably
1125            without too many getpwnam() lookups.  This is particulary nasty for
1126            winbind usernames, where the share name isn't the same as unix
1127            username.
1128
1129            The snum of the homes share is stored on the vuser at session setup
1130            time.
1131         */
1132
1133         if (strequal(service_in,HOMES_NAME)) {
1134                 if(lp_security() != SEC_SHARE) {
1135                         DATA_BLOB no_pw = data_blob_null;
1136                         if (vuser->homes_snum == -1) {
1137                                 DEBUG(2, ("[homes] share not available for "
1138                                           "this user because it was not found "
1139                                           "or created at session setup "
1140                                           "time\n"));
1141                                 *status = NT_STATUS_BAD_NETWORK_NAME;
1142                                 return NULL;
1143                         }
1144                         DEBUG(5, ("making a connection to [homes] service "
1145                                   "created at session setup time\n"));
1146                         return make_connection_snum(sconn,
1147                                                     vuser->homes_snum,
1148                                                     vuser, no_pw,
1149                                                     dev, status);
1150                 } else {
1151                         /* Security = share. Try with
1152                          * current_user_info.smb_name as the username.  */
1153                         if (*current_user_info.smb_name) {
1154                                 fstring unix_username;
1155                                 fstrcpy(unix_username,
1156                                         current_user_info.smb_name);
1157                                 map_username(unix_username);
1158                                 snum = find_service(unix_username);
1159                         }
1160                         if (snum != -1) {
1161                                 DEBUG(5, ("making a connection to 'homes' "
1162                                           "service %s based on "
1163                                           "security=share\n", service_in));
1164                                 return make_connection_snum(sconn,
1165                                                             snum, NULL,
1166                                                             password,
1167                                                             dev, status);
1168                         }
1169                 }
1170         } else if ((lp_security() != SEC_SHARE) && (vuser->homes_snum != -1)
1171                    && strequal(service_in,
1172                                lp_servicename(vuser->homes_snum))) {
1173                 DATA_BLOB no_pw = data_blob_null;
1174                 DEBUG(5, ("making a connection to 'homes' service [%s] "
1175                           "created at session setup time\n", service_in));
1176                 return make_connection_snum(sconn,
1177                                             vuser->homes_snum,
1178                                             vuser, no_pw,
1179                                             dev, status);
1180         }
1181
1182         fstrcpy(service, service_in);
1183
1184         strlower_m(service);
1185
1186         snum = find_service(service);
1187
1188         if (snum < 0) {
1189                 if (strequal(service,"IPC$") ||
1190                     (lp_enable_asu_support() && strequal(service,"ADMIN$"))) {
1191                         DEBUG(3,("refusing IPC connection to %s\n", service));
1192                         *status = NT_STATUS_ACCESS_DENIED;
1193                         return NULL;
1194                 }
1195
1196                 DEBUG(3,("%s (%s) couldn't find service %s\n",
1197                         get_remote_machine_name(),
1198                         tsocket_address_string(
1199                                 sconn->remote_address, talloc_tos()),
1200                         service));
1201                 *status = NT_STATUS_BAD_NETWORK_NAME;
1202                 return NULL;
1203         }
1204
1205         /* Handle non-Dfs clients attempting connections to msdfs proxy */
1206         if (lp_host_msdfs() && (*lp_msdfs_proxy(snum) != '\0'))  {
1207                 DEBUG(3, ("refusing connection to dfs proxy share '%s' "
1208                           "(pointing to %s)\n",
1209                         service, lp_msdfs_proxy(snum)));
1210                 *status = NT_STATUS_BAD_NETWORK_NAME;
1211                 return NULL;
1212         }
1213
1214         DEBUG(5, ("making a connection to 'normal' service %s\n", service));
1215
1216         return make_connection_snum(sconn, snum, vuser,
1217                                     password,
1218                                     dev, status);
1219 }
1220
1221 /****************************************************************************
1222  Close a cnum.
1223 ****************************************************************************/
1224
1225 void close_cnum(connection_struct *conn, uint16 vuid)
1226 {
1227         file_close_conn(conn);
1228
1229         if (!IS_IPC(conn)) {
1230                 dptr_closecnum(conn);
1231         }
1232
1233         change_to_root_user();
1234
1235         DEBUG(IS_IPC(conn)?3:1, ("%s (%s) closed connection to service %s\n",
1236                                  get_remote_machine_name(),
1237                                  conn->sconn->client_id.addr,
1238                                  lp_servicename(SNUM(conn))));
1239
1240         /* Call VFS disconnect hook */
1241         SMB_VFS_DISCONNECT(conn);
1242
1243         yield_connection(conn, lp_servicename(SNUM(conn)));
1244
1245         /* make sure we leave the directory available for unmount */
1246         vfs_ChDir(conn, "/");
1247
1248         /* execute any "postexec = " line */
1249         if (*lp_postexec(SNUM(conn)) &&
1250             change_to_user(conn, vuid))  {
1251                 char *cmd = talloc_sub_advanced(talloc_tos(),
1252                                         lp_servicename(SNUM(conn)),
1253                                         conn->server_info->unix_name,
1254                                         conn->connectpath,
1255                                         conn->server_info->utok.gid,
1256                                         conn->server_info->sanitized_username,
1257                                         conn->server_info->info3->base.domain.string,
1258                                         lp_postexec(SNUM(conn)));
1259                 smbrun(cmd,NULL);
1260                 TALLOC_FREE(cmd);
1261                 change_to_root_user();
1262         }
1263
1264         change_to_root_user();
1265         /* execute any "root postexec = " line */
1266         if (*lp_rootpostexec(SNUM(conn)))  {
1267                 char *cmd = talloc_sub_advanced(talloc_tos(),
1268                                         lp_servicename(SNUM(conn)),
1269                                         conn->server_info->unix_name,
1270                                         conn->connectpath,
1271                                         conn->server_info->utok.gid,
1272                                         conn->server_info->sanitized_username,
1273                                         conn->server_info->info3->base.domain.string,
1274                                         lp_rootpostexec(SNUM(conn)));
1275                 smbrun(cmd,NULL);
1276                 TALLOC_FREE(cmd);
1277         }
1278
1279         conn_free(conn);
1280 }