source/lib/substitute.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    string substitution functions
   4    Copyright (C) Andrew Tridgell 1992-2000
   5    Copyright (C) Gerald Carter   2006
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21
  22 #include "includes.h"
  23
  24 extern struct current_user current_user;
  25
  26 userdom_struct current_user_info;
  27 fstring remote_proto="UNKNOWN";
  28
  29 /**
  30  * Set the 'local' machine name
  31  * @param local_name the name we are being called
  32  * @param if this is the 'final' name for us, not be be changed again
  33  */
  34
  35 static char *local_machine;
  36
  37 void free_local_machine_name(void)
  38 {
  39         SAFE_FREE(local_machine);
  40 }
  41
  42 bool set_local_machine_name(const char *local_name, bool perm)
  43 {
  44         static bool already_perm = false;
  45         char *tmp_local_machine = NULL;
  46         char addr[INET6_ADDRSTRLEN];
  47         size_t len;
  48
  49         tmp_local_machine = SMB_STRDUP(local_name);
  50         if (!tmp_local_machine) {
  51                 return false;
  52         }
  53         trim_char(tmp_local_machine,' ',' ');
  54
  55         /*
  56          * Windows NT/2k uses "*SMBSERVER" and XP uses "*SMBSERV"
  57          * arrggg!!!
  58          */
  59
  60         if (strequal(tmp_local_machine, "*SMBSERVER") ||
  61                         strequal(tmp_local_machine, "*SMBSERV") )  {
  62                 SAFE_FREE(local_machine);
  63                 local_machine = SMB_STRDUP(client_socket_addr(get_client_fd(),
  64                                         addr, sizeof(addr)) );
  65                 SAFE_FREE(tmp_local_machine);
  66                 return local_machine ? true : false;
  67         }
  68
  69         if (already_perm) {
  70                 return true;
  71         }
  72
  73         SAFE_FREE(local_machine);
  74         len = strlen(tmp_local_machine);
  75         local_machine = SMB_CALLOC_ARRAY(char, len+1);
  76         if (!local_machine) {
  77                 SAFE_FREE(tmp_local_machine);
  78                 return false;
  79         }
  80         /* alpha_strcpy includes the space for the terminating nul. */
  81         alpha_strcpy(local_machine,tmp_local_machine,
  82                         SAFE_NETBIOS_CHARS,len+1);
  83         strlower_m(local_machine);
  84         SAFE_FREE(tmp_local_machine);
  85
  86         already_perm = perm;
  87
  88         return true;
  89 }
  90
  91 const char *get_local_machine_name(void)
  92 {
  93         if (!local_machine || !*local_machine) {
  94                 return global_myname();
  95         }
  96
  97         return local_machine;
  98 }
  99
 100 /**
 101  * Set the 'remote' machine name
 102  * @param remote_name the name our client wants to be called by
 103  * @param if this is the 'final' name for them, not be be changed again
 104  */
 105
 106 static char *remote_machine;
 107
 108 bool set_remote_machine_name(const char *remote_name, bool perm)
 109 {
 110         static bool already_perm = False;
 111         char *tmp_remote_machine;
 112         size_t len;
 113
 114         if (already_perm) {
 115                 return true;
 116         }
 117
 118         tmp_remote_machine = SMB_STRDUP(remote_name);
 119         if (!tmp_remote_machine) {
 120                 return false;
 121         }
 122         trim_char(tmp_remote_machine,' ',' ');
 123
 124         SAFE_FREE(remote_machine);
 125         len = strlen(tmp_remote_machine);
 126         remote_machine = SMB_CALLOC_ARRAY(char, len+1);
 127         if (!remote_machine) {
 128                 SAFE_FREE(tmp_remote_machine);
 129                 return false;
 130         }
 131
 132         /* alpha_strcpy includes the space for the terminating nul. */
 133         alpha_strcpy(remote_machine,tmp_remote_machine,
 134                         SAFE_NETBIOS_CHARS,len+1);
 135         strlower_m(remote_machine);
 136         SAFE_FREE(tmp_remote_machine);
 137
 138         already_perm = perm;
 139
 140         return true;
 141 }
 142
 143 const char *get_remote_machine_name(void)
 144 {
 145         return remote_machine ? remote_machine : "";
 146 }
 147
 148 /*******************************************************************
 149  Setup the string used by %U substitution.
 150 ********************************************************************/
 151
 152 static char *smb_user_name;
 153
 154 void sub_set_smb_name(const char *name)
 155 {
 156         char *tmp;
 157         size_t len;
 158         bool is_machine_account = false;
 159
 160         /* don't let anonymous logins override the name */
 161         if (!name || !*name) {
 162                 return;
 163         }
 164
 165         tmp = SMB_STRDUP(name);
 166         if (!tmp) {
 167                 return;
 168         }
 169         trim_char(tmp, ' ', ' ');
 170         strlower_m(tmp);
 171
 172         len = strlen(tmp);
 173
 174         if (len == 0) {
 175                 SAFE_FREE(tmp);
 176                 return;
 177         }
 178
 179         /* long story but here goes....we have to allow usernames
 180            ending in '$' as they are valid machine account names.
 181            So check for a machine account and re-add the '$'
 182            at the end after the call to alpha_strcpy().   --jerry  */
 183
 184         if (tmp[len-1] == '$') {
 185                 is_machine_account = True;
 186         }
 187
 188         SAFE_FREE(smb_user_name);
 189         smb_user_name = SMB_CALLOC_ARRAY(char, len+1);
 190         if (!smb_user_name) {
 191                 SAFE_FREE(tmp);
 192                 return;
 193         }
 194
 195         /* alpha_strcpy includes the space for the terminating nul. */
 196         alpha_strcpy(smb_user_name, tmp,
 197                         SAFE_NETBIOS_CHARS,
 198                         len+1);
 199
 200         SAFE_FREE(tmp);
 201
 202         if (is_machine_account) {
 203                 len = strlen(smb_user_name);
 204                 smb_user_name[len-1] = '$';
 205         }
 206 }
 207
 208 static const char *get_smb_user_name(void)
 209 {
 210         return smb_user_name ? smb_user_name : "";
 211 }
 212
 213 /*******************************************************************
 214  Setup the strings used by substitutions. Called per packet. Ensure
 215  %U name is set correctly also.
 216
 217  smb_name must be sanitized by alpha_strcpy
 218 ********************************************************************/
 219
 220 void set_current_user_info(const char *smb_name, const char *unix_name,
 221                            const char *full_name, const char *domain)
 222 {
 223         fstrcpy(current_user_info.smb_name, smb_name);
 224         fstrcpy(current_user_info.unix_name, unix_name);
 225         fstrcpy(current_user_info.full_name, full_name);
 226         fstrcpy(current_user_info.domain, domain);
 227
 228         /* The following is safe as current_user_info.smb_name
 229          * has already been sanitised in register_existing_vuid. */
 230
 231         sub_set_smb_name(current_user_info.smb_name);
 232 }
 233
 234 /*******************************************************************
 235  Return the current active user name.
 236 *******************************************************************/
 237
 238 const char *get_current_username(void)
 239 {
 240         if (current_user_info.smb_name[0] == '\0' ) {
 241                 return get_smb_user_name();
 242         }
 243
 244         return current_user_info.smb_name;
 245 }
 246
 247 /*******************************************************************
 248  Given a pointer to a %$(NAME) in p and the whole string in str
 249  expand it as an environment variable.
 250  Return a new allocated and expanded string.
 251  Based on code by Branko Cibej <branko.cibej@hermes.si>
 252  When this is called p points at the '%' character.
 253  May substitute multiple occurrencies of the same env var.
 254 ********************************************************************/
 255
 256 static char * realloc_expand_env_var(char *str, char *p)
 257 {
 258         char *envname;
 259         char *envval;
 260         char *q, *r;
 261         int copylen;
 262
 263         if (p[0] != '%' || p[1] != '$' || p[2] != '(') {
 264                 return str;
 265         }
 266
 267         /*
 268          * Look for the terminating ')'.
 269          */
 270
 271         if ((q = strchr_m(p,')')) == NULL) {
 272                 DEBUG(0,("expand_env_var: Unterminated environment variable [%s]\n", p));
 273                 return str;
 274         }
 275
 276         /*
 277          * Extract the name from within the %$(NAME) string.
 278          */
 279
 280         r = p + 3;
 281         copylen = q - r;
 282
 283         /* reserve space for use later add %$() chars */
 284         if ( (envname = (char *)SMB_MALLOC(copylen + 1 + 4)) == NULL ) {
 285                 return NULL;
 286         }
 287
 288         strncpy(envname,r,copylen);
 289         envname[copylen] = '\0';
 290
 291         if ((envval = getenv(envname)) == NULL) {
 292                 DEBUG(0,("expand_env_var: Environment variable [%s] not set\n", envname));
 293                 SAFE_FREE(envname);
 294                 return str;
 295         }
 296
 297         /*
 298          * Copy the full %$(NAME) into envname so it
 299          * can be replaced.
 300          */
 301
 302         copylen = q + 1 - p;
 303         strncpy(envname,p,copylen);
 304         envname[copylen] = '\0';
 305         r = realloc_string_sub(str, envname, envval);
 306         SAFE_FREE(envname);
 307
 308         return r;
 309 }
 310
 311 /*******************************************************************
 312 *******************************************************************/
 313
 314 static char *longvar_domainsid( void )
 315 {
 316         DOM_SID sid;
 317         fstring tmp;
 318         char *sid_string;
 319
 320         if ( !secrets_fetch_domain_sid( lp_workgroup(), &sid ) ) {
 321                 return NULL;
 322         }
 323
 324         sid_string = SMB_STRDUP( sid_to_fstring( tmp, &sid ) );
 325
 326         if ( !sid_string ) {
 327                 DEBUG(0,("longvar_domainsid: failed to dup SID string!\n"));
 328         }
 329
 330         return sid_string;
 331 }
 332
 333 /*******************************************************************
 334 *******************************************************************/
 335
 336 struct api_longvar {
 337         const char *name;
 338         char* (*fn)( void );
 339 };
 340
 341 static struct api_longvar longvar_table[] = {
 342         { "DomainSID",          longvar_domainsid },
 343         { NULL,                 NULL }
 344 };
 345
 346 static char *get_longvar_val( const char *varname )
 347 {
 348         int i;
 349
 350         DEBUG(7,("get_longvar_val: expanding variable [%s]\n", varname));
 351
 352         for ( i=0; longvar_table[i].name; i++ ) {
 353                 if ( strequal( longvar_table[i].name, varname ) ) {
 354                         return longvar_table[i].fn();
 355                 }
 356         }
 357
 358         return NULL;
 359 }
 360
 361 /*******************************************************************
 362  Expand the long smb.conf variable names given a pointer to a %(NAME).
 363  Return the number of characters by which the pointer should be advanced.
 364  When this is called p points at the '%' character.
 365 ********************************************************************/
 366
 367 static char *realloc_expand_longvar(char *str, char *p)
 368 {
 369         fstring varname;
 370         char *value;
 371         char *q, *r;
 372         int copylen;
 373
 374         if ( p[0] != '%' || p[1] != '(' ) {
 375                 return str;
 376         }
 377
 378         /* Look for the terminating ')'.*/
 379
 380         if ((q = strchr_m(p,')')) == NULL) {
 381                 DEBUG(0,("realloc_expand_longvar: Unterminated environment variable [%s]\n", p));
 382                 return str;
 383         }
 384
 385         /* Extract the name from within the %(NAME) string.*/
 386
 387         r = p+2;
 388         copylen = MIN( (q-r), (sizeof(varname)-1) );
 389         strncpy(varname, r, copylen);
 390         varname[copylen] = '\0';
 391
 392         if ((value = get_longvar_val(varname)) == NULL) {
 393                 DEBUG(0,("realloc_expand_longvar: Variable [%s] not set.  Skipping\n", varname));
 394                 return str;
 395         }
 396
 397         /* Copy the full %(NAME) into envname so it can be replaced.*/
 398
 399         copylen = MIN( (q+1-p),(sizeof(varname)-1) );
 400         strncpy( varname, p, copylen );
 401         varname[copylen] = '\0';
 402         r = realloc_string_sub(str, varname, value);
 403         SAFE_FREE( value );
 404
 405         /* skip over the %(varname) */
 406
 407         return r;
 408 }
 409
 410 /*******************************************************************
 411  Patch from jkf@soton.ac.uk
 412  Added this to implement %p (NIS auto-map version of %H)
 413 *******************************************************************/
 414
 415 static const char *automount_path(const char *user_name)
 416 {
 417         TALLOC_CTX *ctx = talloc_tos();
 418         const char *server_path;
 419
 420         /* use the passwd entry as the default */
 421         /* this will be the default if WITH_AUTOMOUNT is not used or fails */
 422
 423         server_path = talloc_strdup(ctx, get_user_home_dir(ctx, user_name));
 424         if (!server_path) {
 425                 return "";
 426         }
 427
 428 #if (defined(HAVE_NETGROUP) && defined (WITH_AUTOMOUNT))
 429
 430         if (lp_nis_home_map()) {
 431                 const char *home_path_start;
 432                 char *automount_value = automount_lookup(ctx, user_name);
 433
 434                 if(automount_value && strlen(automount_value) > 0) {
 435                         home_path_start = strchr_m(automount_value,':');
 436                         if (home_path_start != NULL) {
 437                                 DEBUG(5, ("NIS lookup succeeded. "
 438                                         "Home path is: %s\n",
 439                                         home_path_start ?
 440                                                 (home_path_start+1):""));
 441                                 server_path = talloc_strdup(ctx,
 442                                                         home_path_start+1);
 443                                 if (!server_path) {
 444                                         server_path = "";
 445                                 }
 446                         }
 447                 } else {
 448                         /* NIS key lookup failed: default to
 449                          * user home directory from password file */
 450                         DEBUG(5, ("NIS lookup failed. Using Home path from "
 451                         "passwd file. Home path is: %s\n", server_path ));
 452                 }
 453         }
 454 #endif
 455
 456         DEBUG(4,("Home server path: %s\n", server_path));
 457         return server_path;
 458 }
 459
 460 /*******************************************************************
 461  Patch from jkf@soton.ac.uk
 462  This is Luke's original function with the NIS lookup code
 463  moved out to a separate function.
 464 *******************************************************************/
 465
 466 static const char *automount_server(const char *user_name)
 467 {
 468         TALLOC_CTX *ctx = talloc_tos();
 469         const char *server_name;
 470         const char *local_machine_name = get_local_machine_name();
 471
 472         /* use the local machine name as the default */
 473         /* this will be the default if WITH_AUTOMOUNT is not used or fails */
 474         if (local_machine_name && *local_machine_name) {
 475                 server_name = talloc_strdup(ctx, local_machine_name);
 476         } else {
 477                 server_name = talloc_strdup(ctx, global_myname());
 478         }
 479
 480         if (!server_name) {
 481                 return "";
 482         }
 483
 484 #if (defined(HAVE_NETGROUP) && defined (WITH_AUTOMOUNT))
 485         if (lp_nis_home_map()) {
 486                 char *p;
 487                 char *srv;
 488                 char *automount_value = automount_lookup(ctx, user_name);
 489                 if (!automount_value) {
 490                         return "";
 491                 }
 492                 srv = talloc_strdup(ctx, automount_value);
 493                 if (!srv) {
 494                         return "";
 495                 }
 496                 p = strchr_m(srv, ':');
 497                 if (!p) {
 498                         return "";
 499                 }
 500                 *p = '\0';
 501                 server_name = srv;
 502                 DEBUG(5, ("NIS lookup succeeded.  Home server %s\n",
 503                                         server_name));
 504         }
 505 #endif
 506
 507         DEBUG(4,("Home server: %s\n", server_name));
 508         return server_name;
 509 }
 510
 511 /****************************************************************************
 512  Do some standard substitutions in a string.
 513  len is the length in bytes of the space allowed in string str. If zero means
 514  don't allow expansions.
 515 ****************************************************************************/
 516
 517 void standard_sub_basic(const char *smb_name, const char *domain_name,
 518                         char *str, size_t len)
 519 {
 520         char *s;
 521
 522         if ( (s = alloc_sub_basic( smb_name, domain_name, str )) != NULL ) {
 523                 strncpy( str, s, len );
 524         }
 525
 526         SAFE_FREE( s );
 527
 528 }
 529
 530 /****************************************************************************
 531  Do some standard substitutions in a string.
 532  This function will return an allocated string that have to be freed.
 533 ****************************************************************************/
 534
 535 char *talloc_sub_basic(TALLOC_CTX *mem_ctx, const char *smb_name,
 536                        const char *domain_name, const char *str)
 537 {
 538         char *a, *t;
 539
 540         if ( (a = alloc_sub_basic(smb_name, domain_name, str)) == NULL ) {
 541                 return NULL;
 542         }
 543         t = talloc_strdup(mem_ctx, a);
 544         SAFE_FREE(a);
 545         return t;
 546 }
 547
 548 /****************************************************************************
 549 ****************************************************************************/
 550
 551 char *alloc_sub_basic(const char *smb_name, const char *domain_name,
 552                       const char *str)
 553 {
 554         char *b, *p, *s, *r, *a_string;
 555         fstring pidstr, vnnstr;
 556         char addr[INET6_ADDRSTRLEN];
 557         const char *local_machine_name = get_local_machine_name();
 558         TALLOC_CTX *tmp_ctx = NULL;
 559
 560         /* workaround to prevent a crash while looking at bug #687 */
 561
 562         if (!str) {
 563                 DEBUG(0,("alloc_sub_basic: NULL source string!  This should not happen\n"));
 564                 return NULL;
 565         }
 566
 567         a_string = SMB_STRDUP(str);
 568         if (a_string == NULL) {
 569                 DEBUG(0, ("alloc_sub_basic: Out of memory!\n"));
 570                 return NULL;
 571         }
 572
 573         tmp_ctx = talloc_stackframe();
 574
 575         for (b = s = a_string; (p = strchr_m(s, '%')); s = a_string + (p - b)) {
 576
 577                 r = NULL;
 578                 b = a_string;
 579
 580                 switch (*(p+1)) {
 581                 case 'U' :
 582                         r = strdup_lower(smb_name);
 583                         if (r == NULL) {
 584                                 goto error;
 585                         }
 586                         a_string = realloc_string_sub(a_string, "%U", r);
 587                         break;
 588                 case 'G' : {
 589                         struct passwd *pass;
 590                         r = SMB_STRDUP(smb_name);
 591                         if (r == NULL) {
 592                                 goto error;
 593                         }
 594                         pass = Get_Pwnam_alloc(tmp_ctx, r);
 595                         if (pass != NULL) {
 596                                 a_string = realloc_string_sub(
 597                                         a_string, "%G",
 598                                         gidtoname(pass->pw_gid));
 599                         }
 600                         TALLOC_FREE(pass);
 601                         break;
 602                 }
 603                 case 'D' :
 604                         r = strdup_upper(domain_name);
 605                         if (r == NULL) {
 606                                 goto error;
 607                         }
 608                         a_string = realloc_string_sub(a_string, "%D", r);
 609                         break;
 610                 case 'I' : {
 611                         int offset = 0;
 612                         client_addr(get_client_fd(), addr, sizeof(addr));
 613                         if (strnequal(addr,"::ffff:",7)) {
 614                                 offset = 7;
 615                         }
 616                         a_string = realloc_string_sub(a_string, "%I",
 617                                                       addr + offset);
 618                         break;
 619                 }
 620                 case 'i':
 621                         a_string = realloc_string_sub( a_string, "%i",
 622                                         client_socket_addr(get_client_fd(), addr, sizeof(addr)) );
 623                         break;
 624                 case 'L' :
 625                         if ( StrnCaseCmp(p, "%LOGONSERVER%", strlen("%LOGONSERVER%")) == 0 ) {
 626                                 break;
 627                         }
 628                         if (local_machine_name && *local_machine_name) {
 629                                 a_string = realloc_string_sub(a_string, "%L", local_machine_name);
 630                         } else {
 631                                 a_string = realloc_string_sub(a_string, "%L", global_myname());
 632                         }
 633                         break;
 634                 case 'N':
 635                         a_string = realloc_string_sub(a_string, "%N", automount_server(smb_name));
 636                         break;
 637                 case 'M' :
 638                         a_string = realloc_string_sub(a_string, "%M", client_name(get_client_fd()));
 639                         break;
 640                 case 'R' :
 641                         a_string = realloc_string_sub(a_string, "%R", remote_proto);
 642                         break;
 643                 case 'T' :
 644                         a_string = realloc_string_sub(a_string, "%T", current_timestring(tmp_ctx, False));
 645                         break;
 646                 case 'a' :
 647                         a_string = realloc_string_sub(a_string, "%a",
 648                                         get_remote_arch_str());
 649                         break;
 650                 case 'd' :
 651                         slprintf(pidstr,sizeof(pidstr)-1, "%d",(int)sys_getpid());
 652                         a_string = realloc_string_sub(a_string, "%d", pidstr);
 653                         break;
 654                 case 'h' :
 655                         a_string = realloc_string_sub(a_string, "%h", myhostname());
 656                         break;
 657                 case 'm' :
 658                         a_string = realloc_string_sub(a_string, "%m",
 659                                                       remote_machine
 660                                                       ? remote_machine
 661                                                       : "");
 662                         break;
 663                 case 'v' :
 664                         a_string = realloc_string_sub(a_string, "%v", SAMBA_VERSION_STRING);
 665                         break;
 666                 case 'w' :
 667                         a_string = realloc_string_sub(a_string, "%w", lp_winbind_separator());
 668                         break;
 669                 case '$' :
 670                         a_string = realloc_expand_env_var(a_string, p); /* Expand environment variables */
 671                         break;
 672                 case '(':
 673                         a_string = realloc_expand_longvar( a_string, p );
 674                         break;
 675                 case 'V' :
 676                         slprintf(vnnstr,sizeof(vnnstr)-1, "%u", get_my_vnn());
 677                         a_string = realloc_string_sub(a_string, "%V", vnnstr);
 678                         break;
 679                 default:
 680                         break;
 681                 }
 682
 683                 p++;
 684                 SAFE_FREE(r);
 685
 686                 if (a_string == NULL) {
 687                         goto done;
 688                 }
 689         }
 690
 691         goto done;
 692
 693 error:
 694         SAFE_FREE(a_string);
 695
 696 done:
 697         TALLOC_FREE(tmp_ctx);
 698         return a_string;
 699 }
 700
 701 /****************************************************************************
 702  Do some specific substitutions in a string.
 703  This function will return an allocated string that have to be freed.
 704 ****************************************************************************/
 705
 706 char *talloc_sub_specified(TALLOC_CTX *mem_ctx,
 707                         const char *input_string,
 708                         const char *username,
 709                         const char *domain,
 710                         uid_t uid,
 711                         gid_t gid)
 712 {
 713         char *a_string;
 714         char *ret_string = NULL;
 715         char *b, *p, *s;
 716         TALLOC_CTX *tmp_ctx;
 717
 718         if (!(tmp_ctx = talloc_new(mem_ctx))) {
 719                 DEBUG(0, ("talloc_new failed\n"));
 720                 return NULL;
 721         }
 722
 723         a_string = talloc_strdup(tmp_ctx, input_string);
 724         if (a_string == NULL) {
 725                 DEBUG(0, ("talloc_sub_specified: Out of memory!\n"));
 726                 goto done;
 727         }
 728
 729         for (b = s = a_string; (p = strchr_m(s, '%')); s = a_string + (p - b)) {
 730
 731                 b = a_string;
 732
 733                 switch (*(p+1)) {
 734                 case 'U' :
 735                         a_string = talloc_string_sub(
 736                                 tmp_ctx, a_string, "%U", username);
 737                         break;
 738                 case 'u' :
 739                         a_string = talloc_string_sub(
 740                                 tmp_ctx, a_string, "%u", username);
 741                         break;
 742                 case 'G' :
 743                         if (gid != -1) {
 744                                 a_string = talloc_string_sub(
 745                                         tmp_ctx, a_string, "%G",
 746                                         gidtoname(gid));
 747                         } else {
 748                                 a_string = talloc_string_sub(
 749                                         tmp_ctx, a_string,
 750                                         "%G", "NO_GROUP");
 751                         }
 752                         break;
 753                 case 'g' :
 754                         if (gid != -1) {
 755                                 a_string = talloc_string_sub(
 756                                         tmp_ctx, a_string, "%g",
 757                                         gidtoname(gid));
 758                         } else {
 759                                 a_string = talloc_string_sub(
 760                                         tmp_ctx, a_string, "%g", "NO_GROUP");
 761                         }
 762                         break;
 763                 case 'D' :
 764                         a_string = talloc_string_sub(tmp_ctx, a_string,
 765                                                      "%D", domain);
 766                         break;
 767                 case 'N' :
 768                         a_string = talloc_string_sub(
 769                                 tmp_ctx, a_string, "%N",
 770                                 automount_server(username));
 771                         break;
 772                 default:
 773                         break;
 774                 }
 775
 776                 p++;
 777                 if (a_string == NULL) {
 778                         goto done;
 779                 }
 780         }
 781
 782         /* Watch out, using "mem_ctx" here, so all intermediate stuff goes
 783          * away with the TALLOC_FREE(tmp_ctx) further down. */
 784
 785         ret_string = talloc_sub_basic(mem_ctx, username, domain, a_string);
 786
 787  done:
 788         TALLOC_FREE(tmp_ctx);
 789         return ret_string;
 790 }
 791
 792 /****************************************************************************
 793 ****************************************************************************/
 794
 795 static char *alloc_sub_advanced(const char *servicename, const char *user,
 796                          const char *connectpath, gid_t gid,
 797                          const char *smb_name, const char *domain_name,
 798                          const char *str)
 799 {
 800         char *a_string, *ret_string;
 801         char *b, *p, *s;
 802
 803         a_string = SMB_STRDUP(str);
 804         if (a_string == NULL) {
 805                 DEBUG(0, ("alloc_sub_advanced: Out of memory!\n"));
 806                 return NULL;
 807         }
 808
 809         for (b = s = a_string; (p = strchr_m(s, '%')); s = a_string + (p - b)) {
 810
 811                 b = a_string;
 812
 813                 switch (*(p+1)) {
 814                 case 'N' :
 815                         a_string = realloc_string_sub(a_string, "%N", automount_server(user));
 816                         break;
 817                 case 'H': {
 818                         char *h;
 819                         if ((h = get_user_home_dir(talloc_tos(), user)))
 820                                 a_string = realloc_string_sub(a_string, "%H", h);
 821                         TALLOC_FREE(h);
 822                         break;
 823                 }
 824                 case 'P':
 825                         a_string = realloc_string_sub(a_string, "%P", connectpath);
 826                         break;
 827                 case 'S':
 828                         a_string = realloc_string_sub(a_string, "%S", servicename);
 829                         break;
 830                 case 'g':
 831                         a_string = realloc_string_sub(a_string, "%g", gidtoname(gid));
 832                         break;
 833                 case 'u':
 834                         a_string = realloc_string_sub(a_string, "%u", user);
 835                         break;
 836
 837                         /* Patch from jkf@soton.ac.uk Left the %N (NIS
 838                          * server name) in standard_sub_basic as it is
 839                          * a feature for logon servers, hence uses the
 840                          * username.  The %p (NIS server path) code is
 841                          * here as it is used instead of the default
 842                          * "path =" string in [homes] and so needs the
 843                          * service name, not the username.  */
 844                 case 'p':
 845                         a_string = realloc_string_sub(a_string, "%p",
 846                                                       automount_path(servicename));
 847                         break;
 848
 849                 default:
 850                         break;
 851                 }
 852
 853                 p++;
 854                 if (a_string == NULL) {
 855                         return NULL;
 856                 }
 857         }
 858
 859         ret_string = alloc_sub_basic(smb_name, domain_name, a_string);
 860         SAFE_FREE(a_string);
 861         return ret_string;
 862 }
 863
 864 /*
 865  * This obviously is inefficient and needs to be merged into
 866  * alloc_sub_advanced...
 867  */
 868
 869 char *talloc_sub_advanced(TALLOC_CTX *mem_ctx,
 870                           const char *servicename, const char *user,
 871                           const char *connectpath, gid_t gid,
 872                           const char *smb_name, const char *domain_name,
 873                           const char *str)
 874 {
 875         char *a, *t;
 876
 877         if (!(a = alloc_sub_advanced(servicename, user, connectpath, gid,
 878                                      smb_name, domain_name, str))) {
 879                 return NULL;
 880         }
 881         t = talloc_strdup(mem_ctx, a);
 882         SAFE_FREE(a);
 883         return t;
 884 }
 885
 886
 887 void standard_sub_advanced(const char *servicename, const char *user,
 888                            const char *connectpath, gid_t gid,
 889                            const char *smb_name, const char *domain_name,
 890                            char *str, size_t len)
 891 {
 892         char *s;
 893
 894         s = alloc_sub_advanced(servicename, user, connectpath,
 895                                gid, smb_name, domain_name, str);
 896
 897         if ( s ) {
 898                 strncpy( str, s, len );
 899                 SAFE_FREE( s );
 900         }
 901 }
 902
 903 /****************************************************************************
 904  Do some standard substitutions in a string.
 905 ****************************************************************************/
 906
 907 char *standard_sub_conn(TALLOC_CTX *ctx, connection_struct *conn, const char *str)
 908 {
 909         return talloc_sub_advanced(ctx,
 910                                 lp_servicename(SNUM(conn)),
 911                                 conn->server_info->unix_name,
 912                                 conn->connectpath,
 913                                 conn->server_info->utok.gid,
 914                                 get_smb_user_name(),
 915                                 "",
 916                                 str);
 917 }