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 "system/filesys.h"
  22 #include "system/passwd.h" /* uid_wrapper */
  23 #include "../lib/tsocket/tsocket.h"
  24 #include "smbd/smbd.h"
  25 #include "smbd/globals.h"
  26 #include "../librpc/gen_ndr/netlogon.h"
  27 #include "../libcli/security/security.h"
  28 #include "printing/pcap.h"
  29 #include "passdb/lookup_sid.h"
  30 #include "auth.h"
  31 #include "lib/param/loadparm.h"
  32 #include "messages.h"
  33
  34 static bool canonicalize_connect_path(connection_struct *conn)
  35 {
  36         bool ret;
  37         char *resolved_name = SMB_VFS_REALPATH(conn,conn->connectpath);
  38         if (!resolved_name) {
  39                 return false;
  40         }
  41         ret = set_conn_connectpath(conn,resolved_name);
  42         SAFE_FREE(resolved_name);
  43         return ret;
  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 = (char *)talloc_size(conn, 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(talloc_tos(), SNUM(conn)), destname ));
 164
 165         talloc_free(conn->connectpath);
 166         conn->connectpath = destname;
 167         /* Ensure conn->cwd is initialized - start as conn->connectpath. */
 168         TALLOC_FREE(conn->cwd);
 169         conn->cwd = talloc_strdup(conn, conn->connectpath);
 170         if (!conn->cwd) {
 171                 return false;
 172         }
 173         return true;
 174 }
 175
 176 /****************************************************************************
 177  Load parameters specific to a connection/service.
 178 ****************************************************************************/
 179
 180 bool set_current_service(connection_struct *conn, uint16 flags, bool do_chdir)
 181 {
 182         int snum;
 183
 184         if (!conn)  {
 185                 last_conn = NULL;
 186                 return(False);
 187         }
 188
 189         conn->lastused_count++;
 190
 191         snum = SNUM(conn);
 192
 193         if (do_chdir &&
 194             vfs_ChDir(conn,conn->connectpath) != 0 &&
 195             vfs_ChDir(conn,conn->origpath) != 0) {
 196                 DEBUG(((errno!=EACCES)?0:3),("chdir (%s) failed, reason: %s\n",
 197                          conn->connectpath, strerror(errno)));
 198                 return(False);
 199         }
 200
 201         if ((conn == last_conn) && (last_flags == flags)) {
 202                 return(True);
 203         }
 204
 205         last_conn = conn;
 206         last_flags = flags;
 207
 208         /* Obey the client case sensitivity requests - only for clients that support it. */
 209         switch (lp_casesensitive(snum)) {
 210                 case Auto:
 211                         {
 212                                 /* We need this uglyness due to DOS/Win9x clients that lie about case insensitivity. */
 213                                 enum remote_arch_types ra_type = get_remote_arch();
 214                                 if ((ra_type != RA_SAMBA) && (ra_type != RA_CIFSFS)) {
 215                                         /* Client can't support per-packet case sensitive pathnames. */
 216                                         conn->case_sensitive = False;
 217                                 } else {
 218                                         conn->case_sensitive = !(flags & FLAG_CASELESS_PATHNAMES);
 219                                 }
 220                         }
 221                         break;
 222                 case True:
 223                         conn->case_sensitive = True;
 224                         break;
 225                 default:
 226                         conn->case_sensitive = False;
 227                         break;
 228         }
 229         return(True);
 230 }
 231
 232 /****************************************************************************
 233  do some basic sainity checks on the share.
 234  This function modifies dev, ecode.
 235 ****************************************************************************/
 236
 237 static NTSTATUS share_sanity_checks(const struct tsocket_address *remote_address,
 238                                     const char *rhost,
 239                                     int snum,
 240                                     fstring dev)
 241 {
 242         char *raddr;
 243
 244         raddr = tsocket_address_inet_addr_string(remote_address,
 245                                                  talloc_tos());
 246         if (raddr == NULL) {
 247                 return NT_STATUS_NO_MEMORY;
 248         }
 249
 250         if (!lp_snum_ok(snum) ||
 251             !allow_access(lp_hostsdeny(snum), lp_hostsallow(snum),
 252                           rhost, raddr)) {
 253                 return NT_STATUS_ACCESS_DENIED;
 254         }
 255
 256         if (dev[0] == '?' || !dev[0]) {
 257                 if (lp_print_ok(snum)) {
 258                         fstrcpy(dev,"LPT1:");
 259                 } else if (strequal(lp_fstype(talloc_tos(), snum), "IPC")) {
 260                         fstrcpy(dev, "IPC");
 261                 } else {
 262                         fstrcpy(dev,"A:");
 263                 }
 264         }
 265
 266         if (!strupper_m(dev)) {
 267                 DEBUG(2,("strupper_m %s failed\n", dev));
 268                 return NT_STATUS_INVALID_PARAMETER;
 269         }
 270
 271         if (lp_print_ok(snum)) {
 272                 if (!strequal(dev, "LPT1:")) {
 273                         return NT_STATUS_BAD_DEVICE_TYPE;
 274                 }
 275         } else if (strequal(lp_fstype(talloc_tos(), snum), "IPC")) {
 276                 if (!strequal(dev, "IPC")) {
 277                         return NT_STATUS_BAD_DEVICE_TYPE;
 278                 }
 279         } else if (!strequal(dev, "A:")) {
 280                 return NT_STATUS_BAD_DEVICE_TYPE;
 281         }
 282
 283         /* Behave as a printer if we are supposed to */
 284         if (lp_print_ok(snum) && (strcmp(dev, "A:") == 0)) {
 285                 fstrcpy(dev, "LPT1:");
 286         }
 287
 288         return NT_STATUS_OK;
 289 }
 290
 291 /*
 292  * Go through lookup_name etc to find the force'd group.
 293  *
 294  * Create a new token from src_token, replacing the primary group sid with the
 295  * one found.
 296  */
 297
 298 static NTSTATUS find_forced_group(bool force_user,
 299                                   int snum, const char *username,
 300                                   struct dom_sid *pgroup_sid,
 301                                   gid_t *pgid)
 302 {
 303         NTSTATUS result = NT_STATUS_NO_SUCH_GROUP;
 304         TALLOC_CTX *frame = talloc_stackframe();
 305         struct dom_sid group_sid;
 306         enum lsa_SidType type;
 307         char *groupname;
 308         bool user_must_be_member = False;
 309         gid_t gid;
 310
 311         groupname = lp_force_group(talloc_tos(), snum);
 312         if (groupname == NULL) {
 313                 DEBUG(1, ("talloc_strdup failed\n"));
 314                 result = NT_STATUS_NO_MEMORY;
 315                 goto done;
 316         }
 317
 318         if (groupname[0] == '+') {
 319                 user_must_be_member = True;
 320                 groupname += 1;
 321         }
 322
 323         groupname = talloc_string_sub(talloc_tos(), groupname,
 324                                       "%S", lp_servicename(talloc_tos(), snum));
 325         if (groupname == NULL) {
 326                 DEBUG(1, ("talloc_string_sub failed\n"));
 327                 result = NT_STATUS_NO_MEMORY;
 328                 goto done;
 329         }
 330
 331         if (!lookup_name_smbconf(talloc_tos(), groupname,
 332                          LOOKUP_NAME_ALL|LOOKUP_NAME_GROUP,
 333                          NULL, NULL, &group_sid, &type)) {
 334                 DEBUG(10, ("lookup_name_smbconf(%s) failed\n",
 335                            groupname));
 336                 goto done;
 337         }
 338
 339         if ((type != SID_NAME_DOM_GRP) && (type != SID_NAME_ALIAS) &&
 340             (type != SID_NAME_WKN_GRP)) {
 341                 DEBUG(10, ("%s is a %s, not a group\n", groupname,
 342                            sid_type_lookup(type)));
 343                 goto done;
 344         }
 345
 346         if (!sid_to_gid(&group_sid, &gid)) {
 347                 DEBUG(10, ("sid_to_gid(%s) for %s failed\n",
 348                            sid_string_dbg(&group_sid), groupname));
 349                 goto done;
 350         }
 351
 352         /*
 353          * If the user has been forced and the forced group starts with a '+',
 354          * then we only set the group to be the forced group if the forced
 355          * user is a member of that group.  Otherwise, the meaning of the '+'
 356          * would be ignored.
 357          */
 358
 359         if (force_user && user_must_be_member) {
 360                 if (user_in_group_sid(username, &group_sid)) {
 361                         sid_copy(pgroup_sid, &group_sid);
 362                         *pgid = gid;
 363                         DEBUG(3,("Forced group %s for member %s\n",
 364                                  groupname, username));
 365                 } else {
 366                         DEBUG(0,("find_forced_group: forced user %s is not a member "
 367                                 "of forced group %s. Disallowing access.\n",
 368                                 username, groupname ));
 369                         result = NT_STATUS_MEMBER_NOT_IN_GROUP;
 370                         goto done;
 371                 }
 372         } else {
 373                 sid_copy(pgroup_sid, &group_sid);
 374                 *pgid = gid;
 375                 DEBUG(3,("Forced group %s\n", groupname));
 376         }
 377
 378         result = NT_STATUS_OK;
 379  done:
 380         TALLOC_FREE(frame);
 381         return result;
 382 }
 383
 384 /****************************************************************************
 385   Create an auth_session_info structure for a connection_struct
 386 ****************************************************************************/
 387
 388 static NTSTATUS create_connection_session_info(struct smbd_server_connection *sconn,
 389                                               TALLOC_CTX *mem_ctx, int snum,
 390                                               struct auth_session_info *session_info,
 391                                               struct auth_session_info **presult)
 392 {
 393         struct auth_session_info *result;
 394
 395         if (lp_guest_only(snum)) {
 396                 return make_session_info_guest(mem_ctx, presult);
 397         }
 398
 399         /*
 400          * This is the normal security != share case where we have a
 401          * valid vuid from the session setup.                 */
 402
 403         if (security_session_user_level(session_info, NULL) < SECURITY_USER) {
 404                 if (!lp_guest_ok(snum)) {
 405                         DEBUG(2, ("guest user (from session setup) "
 406                                   "not permitted to access this share "
 407                                   "(%s)\n", lp_servicename(talloc_tos(), snum)));
 408                         return NT_STATUS_ACCESS_DENIED;
 409                 }
 410         } else {
 411                 if (!user_ok_token(session_info->unix_info->unix_name,
 412                                    session_info->info->domain_name,
 413                                    session_info->security_token, snum)) {
 414                         DEBUG(2, ("user '%s' (from session setup) not "
 415                                   "permitted to access this share "
 416                                   "(%s)\n",
 417                                   session_info->unix_info->unix_name,
 418                                   lp_servicename(talloc_tos(), snum)));
 419                         return NT_STATUS_ACCESS_DENIED;
 420                 }
 421         }
 422
 423         result = copy_session_info(mem_ctx, session_info);
 424         if (result == NULL) {
 425                 return NT_STATUS_NO_MEMORY;
 426         }
 427
 428         *presult = result;
 429         return NT_STATUS_OK;
 430 }
 431
 432 /****************************************************************************
 433   set relavent user and group settings corresponding to force user/group
 434   configuration for the given snum.
 435 ****************************************************************************/
 436
 437 NTSTATUS set_conn_force_user_group(connection_struct *conn, int snum)
 438 {
 439         NTSTATUS status;
 440
 441         if (*lp_force_user(talloc_tos(), snum)) {
 442
 443                 /*
 444                  * Replace conn->session_info with a completely faked up one
 445                  * from the username we are forced into :-)
 446                  */
 447
 448                 char *fuser;
 449                 char *sanitized_username;
 450                 struct auth_session_info *forced_serverinfo;
 451                 bool guest;
 452
 453                 fuser = talloc_string_sub(conn, lp_force_user(talloc_tos(), snum), "%S",
 454                                           lp_const_servicename(snum));
 455                 if (fuser == NULL) {
 456                         return NT_STATUS_NO_MEMORY;
 457                 }
 458
 459                 guest = security_session_user_level(conn->session_info, NULL) < SECURITY_USER;
 460
 461                 status = make_session_info_from_username(
 462                         conn, fuser,
 463                         guest,
 464                         &forced_serverinfo);
 465                 if (!NT_STATUS_IS_OK(status)) {
 466                         return status;
 467                 }
 468
 469                 /* We don't want to replace the original sanitized_username
 470                    as it is the original user given in the connect attempt.
 471                    This is used in '%U' substitutions. */
 472                 sanitized_username = discard_const_p(char,
 473                         forced_serverinfo->unix_info->sanitized_username);
 474                 TALLOC_FREE(sanitized_username);
 475                 forced_serverinfo->unix_info->sanitized_username =
 476                         talloc_move(forced_serverinfo->unix_info,
 477                                 &conn->session_info->unix_info->sanitized_username);
 478
 479                 TALLOC_FREE(conn->session_info);
 480                 conn->session_info = forced_serverinfo;
 481
 482                 conn->force_user = true;
 483                 DEBUG(3,("Forced user %s\n", fuser));
 484         }
 485
 486         /*
 487          * If force group is true, then override
 488          * any groupid stored for the connecting user.
 489          */
 490
 491         if (*lp_force_group(talloc_tos(), snum)) {
 492
 493                 status = find_forced_group(
 494                         conn->force_user, snum, conn->session_info->unix_info->unix_name,
 495                         &conn->session_info->security_token->sids[1],
 496                         &conn->session_info->unix_token->gid);
 497
 498                 if (!NT_STATUS_IS_OK(status)) {
 499                         return status;
 500                 }
 501
 502                 /*
 503                  * We need to cache this gid, to use within
 504                  * change_to_user() separately from the conn->session_info
 505                  * struct. We only use conn->session_info directly if
 506                  * "force_user" was set.
 507                  */
 508                 conn->force_group_gid = conn->session_info->unix_token->gid;
 509         }
 510
 511         return NT_STATUS_OK;
 512 }
 513
 514 /****************************************************************************
 515   Setup the share access mask for a connection.
 516 ****************************************************************************/
 517
 518 static void create_share_access_mask(connection_struct *conn, int snum)
 519 {
 520         const struct security_token *token = conn->session_info->security_token;
 521
 522         share_access_check(token,
 523                         lp_servicename(talloc_tos(), snum),
 524                         MAXIMUM_ALLOWED_ACCESS,
 525                         &conn->share_access);
 526
 527         if (!CAN_WRITE(conn)) {
 528                 conn->share_access &=
 529                         ~(SEC_FILE_WRITE_DATA | SEC_FILE_APPEND_DATA |
 530                           SEC_FILE_WRITE_EA | SEC_FILE_WRITE_ATTRIBUTE |
 531                           SEC_DIR_DELETE_CHILD );
 532         }
 533
 534         if (security_token_has_privilege(token, SEC_PRIV_SECURITY)) {
 535                 conn->share_access |= SEC_FLAG_SYSTEM_SECURITY;
 536         }
 537         if (security_token_has_privilege(token, SEC_PRIV_RESTORE)) {
 538                 conn->share_access |= (SEC_RIGHTS_PRIV_RESTORE);
 539         }
 540         if (security_token_has_privilege(token, SEC_PRIV_BACKUP)) {
 541                 conn->share_access |= (SEC_RIGHTS_PRIV_BACKUP);
 542         }
 543         if (security_token_has_privilege(token, SEC_PRIV_TAKE_OWNERSHIP)) {
 544                 conn->share_access |= (SEC_STD_WRITE_OWNER);
 545         }
 546 }
 547
 548 /****************************************************************************
 549   Make a connection, given the snum to connect to, and the vuser of the
 550   connecting user if appropriate.
 551 ****************************************************************************/
 552
 553 static NTSTATUS make_connection_snum(struct smbd_server_connection *sconn,
 554                                         connection_struct *conn,
 555                                         int snum, struct user_struct *vuser,
 556                                         const char *pdev)
 557 {
 558         struct smb_filename *smb_fname_cpath = NULL;
 559         fstring dev;
 560         int ret;
 561         bool on_err_call_dis_hook = false;
 562         uid_t effuid;
 563         gid_t effgid;
 564         NTSTATUS status;
 565
 566         fstrcpy(dev, pdev);
 567
 568         status = share_sanity_checks(sconn->remote_address,
 569                                        sconn->remote_hostname,
 570                                        snum,
 571                                        dev);
 572         if (NT_STATUS_IS_ERR(status)) {
 573                 goto err_root_exit;
 574         }
 575
 576         conn->params->service = snum;
 577
 578         status = create_connection_session_info(sconn,
 579                 conn, snum, vuser->session_info,
 580                 &conn->session_info);
 581
 582         if (!NT_STATUS_IS_OK(status)) {
 583                 DEBUG(1, ("create_connection_session_info failed: %s\n",
 584                           nt_errstr(status)));
 585                 goto err_root_exit;
 586         }
 587
 588         if (lp_guest_only(snum)) {
 589                 conn->force_user = true;
 590         }
 591
 592         conn->num_files_open = 0;
 593         conn->lastused = conn->lastused_count = time(NULL);
 594         conn->printer = (strncmp(dev,"LPT",3) == 0);
 595         conn->ipc = ( (strncmp(dev,"IPC",3) == 0) ||
 596                       ( lp_enable_asu_support() && strequal(dev,"ADMIN$")) );
 597
 598         /* Case options for the share. */
 599         if (lp_casesensitive(snum) == Auto) {
 600                 /* We will be setting this per packet. Set to be case
 601                  * insensitive for now. */
 602                 conn->case_sensitive = False;
 603         } else {
 604                 conn->case_sensitive = (bool)lp_casesensitive(snum);
 605         }
 606
 607         conn->case_preserve = lp_preservecase(snum);
 608         conn->short_case_preserve = lp_shortpreservecase(snum);
 609
 610         conn->encrypt_level = lp_smb_encrypt(snum);
 611
 612         conn->veto_list = NULL;
 613         conn->hide_list = NULL;
 614         conn->veto_oplock_list = NULL;
 615         conn->aio_write_behind_list = NULL;
 616
 617         conn->read_only = lp_readonly(SNUM(conn));
 618
 619         status = set_conn_force_user_group(conn, snum);
 620         if (!NT_STATUS_IS_OK(status)) {
 621                 goto err_root_exit;
 622         }
 623
 624         conn->vuid = vuser->vuid;
 625
 626         {
 627                 char *s = talloc_sub_advanced(talloc_tos(),
 628                                         lp_servicename(talloc_tos(), SNUM(conn)),
 629                                         conn->session_info->unix_info->unix_name,
 630                                         conn->connectpath,
 631                                         conn->session_info->unix_token->gid,
 632                                         conn->session_info->unix_info->sanitized_username,
 633                                         conn->session_info->info->domain_name,
 634                                         lp_pathname(talloc_tos(), snum));
 635                 if (!s) {
 636                         status = NT_STATUS_NO_MEMORY;
 637                         goto err_root_exit;
 638                 }
 639
 640                 if (!set_conn_connectpath(conn,s)) {
 641                         TALLOC_FREE(s);
 642                         status = NT_STATUS_NO_MEMORY;
 643                         goto err_root_exit;
 644                 }
 645                 DEBUG(3,("Connect path is '%s' for service [%s]\n",s,
 646                          lp_servicename(talloc_tos(), snum)));
 647                 TALLOC_FREE(s);
 648         }
 649
 650         /*
 651          * New code to check if there's a share security descripter
 652          * added from NT server manager. This is done after the
 653          * smb.conf checks are done as we need a uid and token. JRA.
 654          *
 655          */
 656
 657         create_share_access_mask(conn, snum);
 658
 659         if ((conn->share_access & FILE_WRITE_DATA) == 0) {
 660                 if ((conn->share_access & FILE_READ_DATA) == 0) {
 661                         /* No access, read or write. */
 662                         DEBUG(0,("make_connection: connection to %s "
 663                                  "denied due to security "
 664                                  "descriptor.\n",
 665                                  lp_servicename(talloc_tos(), snum)));
 666                         status = NT_STATUS_ACCESS_DENIED;
 667                         goto err_root_exit;
 668                 } else {
 669                         conn->read_only = True;
 670                 }
 671         }
 672         /* Initialise VFS function pointers */
 673
 674         if (!smbd_vfs_init(conn)) {
 675                 DEBUG(0, ("vfs_init failed for service %s\n",
 676                           lp_servicename(talloc_tos(), snum)));
 677                 status = NT_STATUS_BAD_NETWORK_NAME;
 678                 goto err_root_exit;
 679         }
 680
 681 /* ROOT Activities: */
 682         /* explicitly check widelinks here so that we can correctly warn
 683          * in the logs. */
 684         widelinks_warning(snum);
 685
 686         /*
 687          * Enforce the max connections parameter.
 688          */
 689
 690         if ((lp_max_connections(snum) > 0)
 691             && (count_current_connections(lp_servicename(talloc_tos(), SNUM(conn)), True) >=
 692                 lp_max_connections(snum))) {
 693
 694                 DEBUG(1, ("Max connections (%d) exceeded for %s\n",
 695                           lp_max_connections(snum),
 696                           lp_servicename(talloc_tos(), snum)));
 697                 status = NT_STATUS_INSUFFICIENT_RESOURCES;
 698                 goto err_root_exit;
 699         }
 700
 701         /* Invoke VFS make connection hook - this must be the first
 702            filesystem operation that we do. */
 703
 704         if (SMB_VFS_CONNECT(conn, lp_servicename(talloc_tos(), snum),
 705                             conn->session_info->unix_info->unix_name) < 0) {
 706                 DEBUG(0,("make_connection: VFS make connection failed!\n"));
 707                 status = NT_STATUS_UNSUCCESSFUL;
 708                 goto err_root_exit;
 709         }
 710
 711         /* Any error exit after here needs to call the disconnect hook. */
 712         on_err_call_dis_hook = true;
 713
 714         if ((!conn->printer) && (!conn->ipc) &&
 715             lp_change_notify(conn->params)) {
 716                 if (sconn->notify_ctx == NULL) {
 717                         sconn->notify_ctx = notify_init(
 718                                 sconn, sconn->msg_ctx, sconn->ev_ctx);
 719                 }
 720                 if (sconn->sys_notify_ctx == NULL) {
 721                         sconn->sys_notify_ctx = sys_notify_context_create(
 722                                 sconn, sconn->ev_ctx);
 723                 }
 724         }
 725
 726         if (lp_kernel_oplocks(snum)) {
 727                 init_kernel_oplocks(conn->sconn);
 728         }
 729
 730         /*
 731          * Fix compatibility issue pointed out by Volker.
 732          * We pass the conn->connectpath to the preexec
 733          * scripts as a parameter, so attempt to canonicalize
 734          * it here before calling the preexec scripts.
 735          * We ignore errors here, as it is possible that
 736          * the conn->connectpath doesn't exist yet and
 737          * the preexec scripts will create them.
 738          */
 739
 740         (void)canonicalize_connect_path(conn);
 741
 742         /* Preexecs are done here as they might make the dir we are to ChDir
 743          * to below */
 744         /* execute any "root preexec = " line */
 745         if (*lp_rootpreexec(talloc_tos(), snum)) {
 746                 char *cmd = talloc_sub_advanced(talloc_tos(),
 747                                         lp_servicename(talloc_tos(), SNUM(conn)),
 748                                         conn->session_info->unix_info->unix_name,
 749                                         conn->connectpath,
 750                                         conn->session_info->unix_token->gid,
 751                                         conn->session_info->unix_info->sanitized_username,
 752                                         conn->session_info->info->domain_name,
 753                                         lp_rootpreexec(talloc_tos(), snum));
 754                 DEBUG(5,("cmd=%s\n",cmd));
 755                 ret = smbrun(cmd,NULL);
 756                 TALLOC_FREE(cmd);
 757                 if (ret != 0 && lp_rootpreexec_close(snum)) {
 758                         DEBUG(1,("root preexec gave %d - failing "
 759                                  "connection\n", ret));
 760                         status = NT_STATUS_ACCESS_DENIED;
 761                         goto err_root_exit;
 762                 }
 763         }
 764
 765 /* USER Activites: */
 766         if (!change_to_user(conn, conn->vuid)) {
 767                 /* No point continuing if they fail the basic checks */
 768                 DEBUG(0,("Can't become connected user!\n"));
 769                 status = NT_STATUS_LOGON_FAILURE;
 770                 goto err_root_exit;
 771         }
 772
 773         effuid = geteuid();
 774         effgid = getegid();
 775
 776         /* Remember that a different vuid can connect later without these
 777          * checks... */
 778
 779         /* Preexecs are done here as they might make the dir we are to ChDir
 780          * to below */
 781
 782         /* execute any "preexec = " line */
 783         if (*lp_preexec(talloc_tos(), snum)) {
 784                 char *cmd = talloc_sub_advanced(talloc_tos(),
 785                                         lp_servicename(talloc_tos(), SNUM(conn)),
 786                                         conn->session_info->unix_info->unix_name,
 787                                         conn->connectpath,
 788                                         conn->session_info->unix_token->gid,
 789                                         conn->session_info->unix_info->sanitized_username,
 790                                         conn->session_info->info->domain_name,
 791                                         lp_preexec(talloc_tos(), snum));
 792                 ret = smbrun(cmd,NULL);
 793                 TALLOC_FREE(cmd);
 794                 if (ret != 0 && lp_preexec_close(snum)) {
 795                         DEBUG(1,("preexec gave %d - failing connection\n",
 796                                  ret));
 797                         status = NT_STATUS_ACCESS_DENIED;
 798                         goto err_root_exit;
 799                 }
 800         }
 801
 802 #ifdef WITH_FAKE_KASERVER
 803         if (lp_afs_share(snum)) {
 804                 afs_login(conn);
 805         }
 806 #endif
 807
 808         /*
 809          * we've finished with the user stuff - go back to root
 810          * so the SMB_VFS_STAT call will only fail on path errors,
 811          * not permission problems.
 812          */
 813         change_to_root_user();
 814 /* ROOT Activites: */
 815
 816         /*
 817          * If widelinks are disallowed we need to canonicalise the connect
 818          * path here to ensure we don't have any symlinks in the
 819          * connectpath. We will be checking all paths on this connection are
 820          * below this directory. We must do this after the VFS init as we
 821          * depend on the realpath() pointer in the vfs table. JRA.
 822          */
 823         if (!lp_widelinks(snum)) {
 824                 if (!canonicalize_connect_path(conn)) {
 825                         DEBUG(0, ("canonicalize_connect_path failed "
 826                         "for service %s, path %s\n",
 827                                 lp_servicename(talloc_tos(), snum),
 828                                 conn->connectpath));
 829                         status = NT_STATUS_BAD_NETWORK_NAME;
 830                         goto err_root_exit;
 831                 }
 832         }
 833
 834         /* Add veto/hide lists */
 835         if (!IS_IPC(conn) && !IS_PRINT(conn)) {
 836                 set_namearray( &conn->veto_list,
 837                                lp_veto_files(talloc_tos(), snum));
 838                 set_namearray( &conn->hide_list,
 839                                lp_hide_files(talloc_tos(), snum));
 840                 set_namearray( &conn->veto_oplock_list,
 841                                lp_veto_oplocks(talloc_tos(), snum));
 842                 set_namearray( &conn->aio_write_behind_list,
 843                                 lp_aio_write_behind(talloc_tos(), snum));
 844         }
 845         status = create_synthetic_smb_fname(talloc_tos(), conn->connectpath,
 846                                             NULL, NULL, &smb_fname_cpath);
 847         if (!NT_STATUS_IS_OK(status)) {
 848                 goto err_root_exit;
 849         }
 850
 851         /* win2000 does not check the permissions on the directory
 852            during the tree connect, instead relying on permission
 853            check during individual operations. To match this behaviour
 854            I have disabled this chdir check (tridge) */
 855         /* the alternative is just to check the directory exists */
 856
 857         if ((ret = SMB_VFS_STAT(conn, smb_fname_cpath)) != 0 ||
 858             !S_ISDIR(smb_fname_cpath->st.st_ex_mode)) {
 859                 if (ret == 0 && !S_ISDIR(smb_fname_cpath->st.st_ex_mode)) {
 860                         DEBUG(0,("'%s' is not a directory, when connecting to "
 861                                  "[%s]\n", conn->connectpath,
 862                                  lp_servicename(talloc_tos(), snum)));
 863                 } else {
 864                         DEBUG(0,("'%s' does not exist or permission denied "
 865                                  "when connecting to [%s] Error was %s\n",
 866                                  conn->connectpath,
 867                                  lp_servicename(talloc_tos(), snum),
 868                                  strerror(errno) ));
 869                 }
 870                 status = NT_STATUS_BAD_NETWORK_NAME;
 871                 goto err_root_exit;
 872         }
 873         conn->base_share_dev = smb_fname_cpath->st.st_ex_dev;
 874
 875         talloc_free(conn->origpath);
 876         conn->origpath = talloc_strdup(conn, conn->connectpath);
 877
 878         /* Figure out the characteristics of the underlying filesystem. This
 879          * assumes that all the filesystem mounted withing a share path have
 880          * the same characteristics, which is likely but not guaranteed.
 881          */
 882
 883         conn->fs_capabilities = SMB_VFS_FS_CAPABILITIES(conn, &conn->ts_res);
 884
 885         /*
 886          * Print out the 'connected as' stuff here as we need
 887          * to know the effective uid and gid we will be using
 888          * (at least initially).
 889          */
 890
 891         if( DEBUGLVL( IS_IPC(conn) ? 3 : 1 ) ) {
 892                 dbgtext( "%s (%s) ", get_remote_machine_name(),
 893                          tsocket_address_string(conn->sconn->remote_address,
 894                                                 talloc_tos()) );
 895                 dbgtext( "%s", srv_is_signing_active(sconn) ? "signed " : "");
 896                 dbgtext( "connect to service %s ",
 897                          lp_servicename(talloc_tos(), snum) );
 898                 dbgtext( "initially as user %s ",
 899                          conn->session_info->unix_info->unix_name );
 900                 dbgtext( "(uid=%d, gid=%d) ", (int)effuid, (int)effgid );
 901                 dbgtext( "(pid %d)\n", (int)getpid() );
 902         }
 903
 904         return status;
 905
 906   err_root_exit:
 907
 908         TALLOC_FREE(smb_fname_cpath);
 909         /* We must exit this function as root. */
 910         if (geteuid() != 0) {
 911                 change_to_root_user();
 912         }
 913         if (on_err_call_dis_hook) {
 914                 /* Call VFS disconnect hook */
 915                 SMB_VFS_DISCONNECT(conn);
 916         }
 917         return status;
 918 }
 919
 920 /****************************************************************************
 921  Make a connection to a service from SMB1. Internal interface.
 922 ****************************************************************************/
 923
 924 static connection_struct *make_connection_smb1(struct smbd_server_connection *sconn,
 925                                         NTTIME now,
 926                                         int snum, struct user_struct *vuser,
 927                                         const char *pdev,
 928                                         NTSTATUS *pstatus)
 929 {
 930         struct smbXsrv_tcon *tcon;
 931         NTSTATUS status;
 932         struct connection_struct *conn;
 933
 934         status = smb1srv_tcon_create(sconn->conn, now, &tcon);
 935         if (!NT_STATUS_IS_OK(status)) {
 936                 DEBUG(0,("make_connection_smb1: Couldn't find free tcon %s.\n",
 937                          nt_errstr(status)));
 938                 *pstatus = status;
 939                 return NULL;
 940         }
 941
 942         conn = conn_new(sconn);
 943         if (!conn) {
 944                 TALLOC_FREE(tcon);
 945
 946                 DEBUG(0,("make_connection_smb1: Couldn't find free connection.\n"));
 947                 *pstatus = NT_STATUS_INSUFFICIENT_RESOURCES;
 948                 return NULL;
 949         }
 950
 951         conn->cnum = tcon->global->tcon_wire_id;
 952         conn->tcon = tcon;
 953
 954         *pstatus = make_connection_snum(sconn,
 955                                         conn,
 956                                         snum,
 957                                         vuser,
 958                                         pdev);
 959         if (!NT_STATUS_IS_OK(*pstatus)) {
 960                 conn_free(conn);
 961                 TALLOC_FREE(tcon);
 962                 return NULL;
 963         }
 964
 965         tcon->global->share_name = lp_servicename(tcon->global, SNUM(conn));
 966         if (tcon->global->share_name == NULL) {
 967                 conn_free(conn);
 968                 TALLOC_FREE(tcon);
 969                 *pstatus = NT_STATUS_NO_MEMORY;
 970                 return NULL;
 971         }
 972         tcon->global->session_global_id =
 973                 vuser->session->global->session_global_id;
 974
 975         tcon->compat = talloc_move(tcon, &conn);
 976         tcon->status = NT_STATUS_OK;
 977
 978         *pstatus = smbXsrv_tcon_update(tcon);
 979         if (!NT_STATUS_IS_OK(*pstatus)) {
 980                 TALLOC_FREE(tcon);
 981                 return NULL;
 982         }
 983
 984         return tcon->compat;
 985 }
 986
 987 /****************************************************************************
 988  Make a connection to a service from SMB2. External SMB2 interface.
 989  We must set cnum before claiming connection.
 990 ****************************************************************************/
 991
 992 connection_struct *make_connection_smb2(struct smbd_server_connection *sconn,
 993                                         struct smbXsrv_tcon *tcon,
 994                                         int snum,
 995                                         struct user_struct *vuser,
 996                                         const char *pdev,
 997                                         NTSTATUS *pstatus)
 998 {
 999         connection_struct *conn = conn_new(sconn);
1000         if (!conn) {
1001                 DEBUG(0,("make_connection_smb2: Couldn't find free connection.\n"));
1002                 *pstatus = NT_STATUS_INSUFFICIENT_RESOURCES;
1003                 return NULL;
1004         }
1005
1006         conn->cnum = tcon->global->tcon_wire_id;
1007         conn->tcon = tcon;
1008
1009         *pstatus = make_connection_snum(sconn,
1010                                         conn,
1011                                         snum,
1012                                         vuser,
1013                                         pdev);
1014         if (!NT_STATUS_IS_OK(*pstatus)) {
1015                 conn_free(conn);
1016                 return NULL;
1017         }
1018         return conn;
1019 }
1020
1021 /****************************************************************************
1022  Make a connection to a service. External SMB1 interface.
1023  *
1024  * @param service
1025 ****************************************************************************/
1026
1027 connection_struct *make_connection(struct smbd_server_connection *sconn,
1028                                    NTTIME now,
1029                                    const char *service_in,
1030                                    const char *pdev, uint64_t vuid,
1031                                    NTSTATUS *status)
1032 {
1033         uid_t euid;
1034         struct user_struct *vuser = NULL;
1035         char *service = NULL;
1036         fstring dev;
1037         int snum = -1;
1038
1039         fstrcpy(dev, pdev);
1040
1041         /* This must ONLY BE CALLED AS ROOT. As it exits this function as
1042          * root. */
1043         if (!non_root_mode() && (euid = geteuid()) != 0) {
1044                 DEBUG(0,("make_connection: PANIC ERROR. Called as nonroot "
1045                          "(%u)\n", (unsigned int)euid ));
1046                 smb_panic("make_connection: PANIC ERROR. Called as nonroot\n");
1047         }
1048
1049         if (conn_num_open(sconn) > 2047) {
1050                 *status = NT_STATUS_INSUFF_SERVER_RESOURCES;
1051                 return NULL;
1052         }
1053
1054         vuser = get_valid_user_struct(sconn, vuid);
1055         if (!vuser) {
1056                 DEBUG(1,("make_connection: refusing to connect with "
1057                          "no session setup\n"));
1058                 *status = NT_STATUS_ACCESS_DENIED;
1059                 return NULL;
1060         }
1061
1062         /* Logic to try and connect to the correct [homes] share, preferably
1063            without too many getpwnam() lookups.  This is particulary nasty for
1064            winbind usernames, where the share name isn't the same as unix
1065            username.
1066
1067            The snum of the homes share is stored on the vuser at session setup
1068            time.
1069         */
1070
1071         if (strequal(service_in,HOMES_NAME)) {
1072                 if (vuser->homes_snum == -1) {
1073                         DEBUG(2, ("[homes] share not available for "
1074                                   "this user because it was not found "
1075                                   "or created at session setup "
1076                                   "time\n"));
1077                         *status = NT_STATUS_BAD_NETWORK_NAME;
1078                         return NULL;
1079                 }
1080                 DEBUG(5, ("making a connection to [homes] service "
1081                           "created at session setup time\n"));
1082                 return make_connection_smb1(sconn, now,
1083                                             vuser->homes_snum,
1084                                             vuser,
1085                                             dev, status);
1086         } else if ((vuser->homes_snum != -1)
1087                    && strequal(service_in,
1088                                lp_servicename(talloc_tos(), vuser->homes_snum))) {
1089                 DEBUG(5, ("making a connection to 'homes' service [%s] "
1090                           "created at session setup time\n", service_in));
1091                 return make_connection_smb1(sconn, now,
1092                                             vuser->homes_snum,
1093                                             vuser,
1094                                             dev, status);
1095         }
1096
1097         service = talloc_strdup(talloc_tos(), service_in);
1098         if (!service) {
1099                 *status = NT_STATUS_NO_MEMORY;
1100                 return NULL;
1101         }
1102
1103         if (!strlower_m(service)) {
1104                 DEBUG(2, ("strlower_m %s failed\n", service));
1105                 *status = NT_STATUS_INVALID_PARAMETER;
1106                 return NULL;
1107         }
1108
1109         snum = find_service(talloc_tos(), service, &service);
1110         if (!service) {
1111                 *status = NT_STATUS_NO_MEMORY;
1112                 return NULL;
1113         }
1114
1115         if (snum < 0) {
1116                 if (strequal(service,"IPC$") ||
1117                     (lp_enable_asu_support() && strequal(service,"ADMIN$"))) {
1118                         DEBUG(3,("refusing IPC connection to %s\n", service));
1119                         *status = NT_STATUS_ACCESS_DENIED;
1120                         return NULL;
1121                 }
1122
1123                 DEBUG(3,("%s (%s) couldn't find service %s\n",
1124                         get_remote_machine_name(),
1125                         tsocket_address_string(
1126                                 sconn->remote_address, talloc_tos()),
1127                         service));
1128                 *status = NT_STATUS_BAD_NETWORK_NAME;
1129                 return NULL;
1130         }
1131
1132         /* Handle non-Dfs clients attempting connections to msdfs proxy */
1133         if (lp_host_msdfs() && (*lp_msdfs_proxy(talloc_tos(), snum) != '\0'))  {
1134                 DEBUG(3, ("refusing connection to dfs proxy share '%s' "
1135                           "(pointing to %s)\n",
1136                         service, lp_msdfs_proxy(talloc_tos(), snum)));
1137                 *status = NT_STATUS_BAD_NETWORK_NAME;
1138                 return NULL;
1139         }
1140
1141         DEBUG(5, ("making a connection to 'normal' service %s\n", service));
1142
1143         return make_connection_smb1(sconn, now, snum, vuser,
1144                                     dev, status);
1145 }
1146
1147 /****************************************************************************
1148  Close a cnum.
1149 ****************************************************************************/
1150
1151 void close_cnum(connection_struct *conn, uint64_t vuid)
1152 {
1153         file_close_conn(conn);
1154
1155         if (!IS_IPC(conn)) {
1156                 dptr_closecnum(conn);
1157         }
1158
1159         change_to_root_user();
1160
1161         DEBUG(IS_IPC(conn)?3:1, ("%s (%s) closed connection to service %s\n",
1162                                  get_remote_machine_name(),
1163                                  tsocket_address_string(conn->sconn->remote_address,
1164                                                         talloc_tos()),
1165                                  lp_servicename(talloc_tos(), SNUM(conn))));
1166
1167         /* Call VFS disconnect hook */
1168         SMB_VFS_DISCONNECT(conn);
1169
1170         /* make sure we leave the directory available for unmount */
1171         vfs_ChDir(conn, "/");
1172
1173         /* execute any "postexec = " line */
1174         if (*lp_postexec(talloc_tos(), SNUM(conn)) &&
1175             change_to_user(conn, vuid))  {
1176                 char *cmd = talloc_sub_advanced(talloc_tos(),
1177                                         lp_servicename(talloc_tos(), SNUM(conn)),
1178                                         conn->session_info->unix_info->unix_name,
1179                                         conn->connectpath,
1180                                         conn->session_info->unix_token->gid,
1181                                         conn->session_info->unix_info->sanitized_username,
1182                                         conn->session_info->info->domain_name,
1183                                         lp_postexec(talloc_tos(), SNUM(conn)));
1184                 smbrun(cmd,NULL);
1185                 TALLOC_FREE(cmd);
1186                 change_to_root_user();
1187         }
1188
1189         change_to_root_user();
1190         /* execute any "root postexec = " line */
1191         if (*lp_rootpostexec(talloc_tos(), SNUM(conn)))  {
1192                 char *cmd = talloc_sub_advanced(talloc_tos(),
1193                                         lp_servicename(talloc_tos(), SNUM(conn)),
1194                                         conn->session_info->unix_info->unix_name,
1195                                         conn->connectpath,
1196                                         conn->session_info->unix_token->gid,
1197                                         conn->session_info->unix_info->sanitized_username,
1198                                         conn->session_info->info->domain_name,
1199                                         lp_rootpostexec(talloc_tos(), SNUM(conn)));
1200                 smbrun(cmd,NULL);
1201                 TALLOC_FREE(cmd);
1202         }
1203
1204         conn_free(conn);
1205 }