source3/utils/sharesec.c

   1 /*
   2  *  Unix SMB/Netbios implementation.
   3  *  Utility for managing share permissions
   4  *
   5  *  Copyright (C) Tim Potter                    2000
   6  *  Copyright (C) Jeremy Allison                2000
   7  *  Copyright (C) Jelmer Vernooij               2003
   8  *  Copyright (C) Gerald (Jerry) Carter         2005.
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 3 of the License, or
  13  *  (at your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful,
  16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  *  GNU General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License
  21  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  22  */
  23
  24
  25 #include "includes.h"
  26
  27 static TALLOC_CTX *ctx;
  28
  29 enum acl_mode { SMB_ACL_DELETE,
  30                 SMB_ACL_MODIFY,
  31                 SMB_ACL_ADD,
  32                 SMB_ACL_SET,
  33                 SMB_ACL_VIEW };
  34
  35 struct perm_value {
  36         const char *perm;
  37         uint32 mask;
  38 };
  39
  40 /* These values discovered by inspection */
  41
  42 static const struct perm_value special_values[] = {
  43         { "R", SEC_RIGHTS_FILE_READ },
  44         { "W", SEC_RIGHTS_FILE_WRITE },
  45         { "X", SEC_RIGHTS_FILE_EXECUTE },
  46         { "D", SEC_STD_DELETE },
  47         { "P", SEC_STD_WRITE_DAC },
  48         { "O", SEC_STD_WRITE_OWNER },
  49         { NULL, 0 },
  50 };
  51
  52 #define SEC_RIGHTS_DIR_CHANGE ( SEC_RIGHTS_DIR_READ|SEC_STD_DELETE|\
  53                                 SEC_RIGHTS_DIR_WRITE|SEC_DIR_TRAVERSE )
  54
  55 static const struct perm_value standard_values[] = {
  56         { "READ",   SEC_RIGHTS_DIR_READ|SEC_DIR_TRAVERSE },
  57         { "CHANGE", SEC_RIGHTS_DIR_CHANGE },
  58         { "FULL",   SEC_RIGHTS_DIR_ALL },
  59         { NULL, 0 },
  60 };
  61
  62 /********************************************************************
  63  print an ACE on a FILE
  64 ********************************************************************/
  65
  66 static void print_ace(FILE *f, SEC_ACE *ace)
  67 {
  68         const struct perm_value *v;
  69         int do_print = 0;
  70         uint32 got_mask;
  71
  72         fprintf(f, "%s:", sid_string_tos(&ace->trustee));
  73
  74         /* Ace type */
  75
  76         if (ace->type == SEC_ACE_TYPE_ACCESS_ALLOWED) {
  77                 fprintf(f, "ALLOWED");
  78         } else if (ace->type == SEC_ACE_TYPE_ACCESS_DENIED) {
  79                 fprintf(f, "DENIED");
  80         } else {
  81                 fprintf(f, "%d", ace->type);
  82         }
  83
  84         /* Not sure what flags can be set in a file ACL */
  85
  86         fprintf(f, "/%d/", ace->flags);
  87
  88         /* Standard permissions */
  89
  90         for (v = standard_values; v->perm; v++) {
  91                 if (ace->access_mask == v->mask) {
  92                         fprintf(f, "%s", v->perm);
  93                         return;
  94                 }
  95         }
  96
  97         /* Special permissions.  Print out a hex value if we have
  98            leftover bits in the mask. */
  99
 100         got_mask = ace->access_mask;
 101
 102  again:
 103         for (v = special_values; v->perm; v++) {
 104                 if ((ace->access_mask & v->mask) == v->mask) {
 105                         if (do_print) {
 106                                 fprintf(f, "%s", v->perm);
 107                         }
 108                         got_mask &= ~v->mask;
 109                 }
 110         }
 111
 112         if (!do_print) {
 113                 if (got_mask != 0) {
 114                         fprintf(f, "0x%08x", ace->access_mask);
 115                 } else {
 116                         do_print = 1;
 117                         goto again;
 118                 }
 119         }
 120 }
 121
 122 /********************************************************************
 123  print an ascii version of a security descriptor on a FILE handle
 124 ********************************************************************/
 125
 126 static void sec_desc_print(FILE *f, SEC_DESC *sd)
 127 {
 128         uint32 i;
 129
 130         fprintf(f, "REVISION:%d\n", sd->revision);
 131
 132         /* Print owner and group sid */
 133
 134         fprintf(f, "OWNER:%s\n", sid_string_tos(sd->owner_sid));
 135
 136         fprintf(f, "GROUP:%s\n", sid_string_tos(sd->group_sid));
 137
 138         /* Print aces */
 139         for (i = 0; sd->dacl && i < sd->dacl->num_aces; i++) {
 140                 SEC_ACE *ace = &sd->dacl->aces[i];
 141                 fprintf(f, "ACL:");
 142                 print_ace(f, ace);
 143                 fprintf(f, "\n");
 144         }
 145 }
 146
 147 /********************************************************************
 148  parse an ACE in the same format as print_ace()
 149 ********************************************************************/
 150
 151 static bool parse_ace(SEC_ACE *ace, const char *orig_str)
 152 {
 153         char *p;
 154         const char *cp;
 155         char *tok;
 156         unsigned int atype = 0;
 157         unsigned int aflags = 0;
 158         unsigned int amask = 0;
 159         DOM_SID sid;
 160         uint32_t mask;
 161         const struct perm_value *v;
 162         char *str = SMB_STRDUP(orig_str);
 163         TALLOC_CTX *frame = talloc_stackframe();
 164
 165         if (!str) {
 166                 TALLOC_FREE(frame);
 167                 return False;
 168         }
 169
 170         ZERO_STRUCTP(ace);
 171         p = strchr_m(str,':');
 172         if (!p) {
 173                 printf("ACE '%s': missing ':'.\n", orig_str);
 174                 SAFE_FREE(str);
 175                 TALLOC_FREE(frame);
 176                 return False;
 177         }
 178         *p = '\0';
 179         p++;
 180         /* Try to parse numeric form */
 181
 182         if (sscanf(p, "%i/%i/%i", &atype, &aflags, &amask) == 3 &&
 183             string_to_sid(&sid, str)) {
 184                 goto done;
 185         }
 186
 187         /* Try to parse text form */
 188
 189         if (!string_to_sid(&sid, str)) {
 190                 printf("ACE '%s': failed to convert '%s' to SID\n",
 191                         orig_str, str);
 192                 SAFE_FREE(str);
 193                 TALLOC_FREE(frame);
 194                 return False;
 195         }
 196
 197         cp = p;
 198         if (!next_token_talloc(frame, &cp, &tok, "/")) {
 199                 printf("ACE '%s': failed to find '/' character.\n",
 200                         orig_str);
 201                 SAFE_FREE(str);
 202                 TALLOC_FREE(frame);
 203                 return False;
 204         }
 205
 206         if (strncmp(tok, "ALLOWED", strlen("ALLOWED")) == 0) {
 207                 atype = SEC_ACE_TYPE_ACCESS_ALLOWED;
 208         } else if (strncmp(tok, "DENIED", strlen("DENIED")) == 0) {
 209                 atype = SEC_ACE_TYPE_ACCESS_DENIED;
 210         } else {
 211                 printf("ACE '%s': missing 'ALLOWED' or 'DENIED' entry at '%s'\n",
 212                         orig_str, tok);
 213                 SAFE_FREE(str);
 214                 TALLOC_FREE(frame);
 215                 return False;
 216         }
 217
 218         /* Only numeric form accepted for flags at present */
 219         /* no flags on share permissions */
 220
 221         if (!(next_token_talloc(frame, &cp, &tok, "/") &&
 222               sscanf(tok, "%i", &aflags) && aflags == 0)) {
 223                 printf("ACE '%s': bad integer flags entry at '%s'\n",
 224                         orig_str, tok);
 225                 SAFE_FREE(str);
 226                 TALLOC_FREE(frame);
 227                 return False;
 228         }
 229
 230         if (!next_token_talloc(frame, &cp, &tok, "/")) {
 231                 printf("ACE '%s': missing / at '%s'\n",
 232                         orig_str, tok);
 233                 SAFE_FREE(str);
 234                 TALLOC_FREE(frame);
 235                 return False;
 236         }
 237
 238         if (strncmp(tok, "0x", 2) == 0) {
 239                 if (sscanf(tok, "%i", &amask) != 1) {
 240                         printf("ACE '%s': bad hex number at '%s'\n",
 241                                 orig_str, tok);
 242                         TALLOC_FREE(frame);
 243                         SAFE_FREE(str);
 244                         return False;
 245                 }
 246                 goto done;
 247         }
 248
 249         for (v = standard_values; v->perm; v++) {
 250                 if (strcmp(tok, v->perm) == 0) {
 251                         amask = v->mask;
 252                         goto done;
 253                 }
 254         }
 255
 256         p = tok;
 257
 258         while(*p) {
 259                 bool found = False;
 260
 261                 for (v = special_values; v->perm; v++) {
 262                         if (v->perm[0] == *p) {
 263                                 amask |= v->mask;
 264                                 found = True;
 265                         }
 266                 }
 267
 268                 if (!found) {
 269                         printf("ACE '%s': bad permission value at '%s'\n",
 270                                 orig_str, p);
 271                         TALLOC_FREE(frame);
 272                         SAFE_FREE(str);
 273                         return False;
 274                 }
 275                 p++;
 276         }
 277
 278         if (*p) {
 279                 TALLOC_FREE(frame);
 280                 SAFE_FREE(str);
 281                 return False;
 282         }
 283
 284  done:
 285         mask = amask;
 286         init_sec_ace(ace, &sid, atype, mask, aflags);
 287         SAFE_FREE(str);
 288         TALLOC_FREE(frame);
 289         return True;
 290 }
 291
 292
 293 /********************************************************************
 294 ********************************************************************/
 295
 296 static SEC_DESC* parse_acl_string(TALLOC_CTX *mem_ctx, const char *szACL, size_t *sd_size )
 297 {
 298         SEC_DESC *sd = NULL;
 299         SEC_ACE *ace;
 300         SEC_ACL *acl;
 301         int num_ace;
 302         const char *pacl;
 303         int i;
 304
 305         if ( !szACL )
 306                 return NULL;
 307
 308         pacl = szACL;
 309         num_ace = count_chars( pacl, ',' ) + 1;
 310
 311         if ( !(ace = TALLOC_ZERO_ARRAY( mem_ctx, SEC_ACE, num_ace )) )
 312                 return NULL;
 313
 314         for ( i=0; i<num_ace; i++ ) {
 315                 char *end_acl = strchr_m( pacl, ',' );
 316                 fstring acl_string;
 317
 318                 strncpy( acl_string, pacl, MIN( PTR_DIFF( end_acl, pacl ), sizeof(fstring)-1) );
 319                 acl_string[MIN( PTR_DIFF( end_acl, pacl ), sizeof(fstring)-1)] = '\0';
 320
 321                 if ( !parse_ace( &ace[i], acl_string ) )
 322                         return NULL;
 323
 324                 pacl = end_acl;
 325                 pacl++;
 326         }
 327
 328         if ( !(acl = make_sec_acl( mem_ctx, NT4_ACL_REVISION, num_ace, ace )) )
 329                 return NULL;
 330
 331         sd = make_sec_desc( mem_ctx, SEC_DESC_REVISION, SEC_DESC_SELF_RELATIVE,
 332                 NULL, NULL, NULL, acl, sd_size);
 333
 334         return sd;
 335 }
 336
 337 /* add an ACE to a list of ACEs in a SEC_ACL */
 338 static bool add_ace(TALLOC_CTX *mem_ctx, SEC_ACL **the_acl, SEC_ACE *ace)
 339 {
 340         SEC_ACL *new_ace;
 341         SEC_ACE *aces;
 342         if (! *the_acl) {
 343                 return (((*the_acl) = make_sec_acl(mem_ctx, 3, 1, ace)) != NULL);
 344         }
 345
 346         if (!(aces = SMB_CALLOC_ARRAY(SEC_ACE, 1+(*the_acl)->num_aces))) {
 347                 return False;
 348         }
 349         memcpy(aces, (*the_acl)->aces, (*the_acl)->num_aces * sizeof(SEC_ACE));
 350         memcpy(aces+(*the_acl)->num_aces, ace, sizeof(SEC_ACE));
 351         new_ace = make_sec_acl(mem_ctx,(*the_acl)->revision,1+(*the_acl)->num_aces, aces);
 352         SAFE_FREE(aces);
 353         (*the_acl) = new_ace;
 354         return True;
 355 }
 356
 357 /* The MSDN is contradictory over the ordering of ACE entries in an ACL.
 358    However NT4 gives a "The information may have been modified by a
 359    computer running Windows NT 5.0" if denied ACEs do not appear before
 360    allowed ACEs. */
 361
 362 static int ace_compare(SEC_ACE *ace1, SEC_ACE *ace2)
 363 {
 364         if (sec_ace_equal(ace1, ace2))
 365                 return 0;
 366
 367         if (ace1->type != ace2->type)
 368                 return ace2->type - ace1->type;
 369
 370         if (sid_compare(&ace1->trustee, &ace2->trustee))
 371                 return sid_compare(&ace1->trustee, &ace2->trustee);
 372
 373         if (ace1->flags != ace2->flags)
 374                 return ace1->flags - ace2->flags;
 375
 376         if (ace1->access_mask != ace2->access_mask)
 377                 return ace1->access_mask - ace2->access_mask;
 378
 379         if (ace1->size != ace2->size)
 380                 return ace1->size - ace2->size;
 381
 382         return memcmp(ace1, ace2, sizeof(SEC_ACE));
 383 }
 384
 385 static void sort_acl(SEC_ACL *the_acl)
 386 {
 387         uint32 i;
 388         if (!the_acl) return;
 389
 390         qsort(the_acl->aces, the_acl->num_aces, sizeof(the_acl->aces[0]), QSORT_CAST ace_compare);
 391
 392         for (i=1;i<the_acl->num_aces;) {
 393                 if (sec_ace_equal(&the_acl->aces[i-1], &the_acl->aces[i])) {
 394                         int j;
 395                         for (j=i; j<the_acl->num_aces-1; j++) {
 396                                 the_acl->aces[j] = the_acl->aces[j+1];
 397                         }
 398                         the_acl->num_aces--;
 399                 } else {
 400                         i++;
 401                 }
 402         }
 403 }
 404
 405
 406 static int change_share_sec(TALLOC_CTX *mem_ctx, const char *sharename, char *the_acl, enum acl_mode mode)
 407 {
 408         SEC_DESC *sd = NULL;
 409         SEC_DESC *old = NULL;
 410         size_t sd_size = 0;
 411         uint32 i, j;
 412
 413         if (mode != SMB_ACL_SET) {
 414             if (!(old = get_share_security( mem_ctx, sharename, &sd_size )) ) {
 415                 fprintf(stderr, "Unable to retrieve permissions for share [%s]\n", sharename);
 416                 return -1;
 417             }
 418         }
 419
 420         if ( (mode != SMB_ACL_VIEW) && !(sd = parse_acl_string(mem_ctx, the_acl, &sd_size )) ) {
 421                 fprintf( stderr, "Failed to parse acl\n");
 422                 return -1;
 423         }
 424
 425         switch (mode) {
 426         case SMB_ACL_VIEW:
 427                 sec_desc_print( stdout, old);
 428                 return 0;
 429         case SMB_ACL_DELETE:
 430             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 431                 bool found = False;
 432
 433                 for (j=0;old->dacl && j<old->dacl->num_aces;j++) {
 434                     if (sec_ace_equal(&sd->dacl->aces[i], &old->dacl->aces[j])) {
 435                         uint32 k;
 436                         for (k=j; k<old->dacl->num_aces-1;k++) {
 437                             old->dacl->aces[k] = old->dacl->aces[k+1];
 438                         }
 439                         old->dacl->num_aces--;
 440                         found = True;
 441                         break;
 442                     }
 443                 }
 444
 445                 if (!found) {
 446                 printf("ACL for ACE:");
 447                 print_ace(stdout, &sd->dacl->aces[i]);
 448                 printf(" not found\n");
 449                 }
 450             }
 451
 452             break;
 453         case SMB_ACL_MODIFY:
 454             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 455                 bool found = False;
 456
 457                 for (j=0;old->dacl && j<old->dacl->num_aces;j++) {
 458                     if (sid_equal(&sd->dacl->aces[i].trustee,
 459                         &old->dacl->aces[j].trustee)) {
 460                         old->dacl->aces[j] = sd->dacl->aces[i];
 461                         found = True;
 462                     }
 463                 }
 464
 465                 if (!found) {
 466                     printf("ACL for SID %s not found\n",
 467                            sid_string_tos(&sd->dacl->aces[i].trustee));
 468                 }
 469             }
 470
 471             if (sd->owner_sid) {
 472                 old->owner_sid = sd->owner_sid;
 473             }
 474
 475             if (sd->group_sid) {
 476                 old->group_sid = sd->group_sid;
 477             }
 478             break;
 479         case SMB_ACL_ADD:
 480             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 481                 add_ace(mem_ctx, &old->dacl, &sd->dacl->aces[i]);
 482             }
 483             break;
 484         case SMB_ACL_SET:
 485             old = sd;
 486             break;
 487         }
 488
 489         /* Denied ACE entries must come before allowed ones */
 490         sort_acl(old->dacl);
 491
 492         if ( !set_share_security( sharename, old ) ) {
 493             fprintf( stderr, "Failed to store acl for share [%s]\n", sharename );
 494             return 2;
 495         }
 496         return 0;
 497 }
 498
 499 /********************************************************************
 500   main program
 501 ********************************************************************/
 502
 503 int main(int argc, const char *argv[])
 504 {
 505         int opt;
 506         int retval = 0;
 507         enum acl_mode mode = SMB_ACL_SET;
 508         static char *the_acl = NULL;
 509         fstring sharename;
 510         bool force_acl = False;
 511         int snum;
 512         poptContext pc;
 513         bool initialize_sid = False;
 514         struct poptOption long_options[] = {
 515                 POPT_AUTOHELP
 516                 { "remove", 'r', POPT_ARG_STRING, &the_acl, 'r', "Delete an ACE", "ACL" },
 517                 { "modify", 'm', POPT_ARG_STRING, &the_acl, 'm', "Modify an acl", "ACL" },
 518                 { "add", 'a', POPT_ARG_STRING, &the_acl, 'a', "Add an ACE", "ACL" },
 519                 { "replace", 'R', POPT_ARG_STRING, &the_acl, 'R', "Set share mission ACL", "ACLS" },
 520                 { "view", 'v', POPT_ARG_NONE, NULL, 'v', "View current share permissions" },
 521                 { "machine-sid", 'M', POPT_ARG_NONE, NULL, 'M', "Initialize the machine SID" },
 522                 { "force", 'F', POPT_ARG_NONE, NULL, 'F', "Force storing the ACL", "ACLS" },
 523                 POPT_COMMON_SAMBA
 524                 { NULL }
 525         };
 526
 527         if ( !(ctx = talloc_stackframe()) ) {
 528                 fprintf( stderr, "Failed to initialize talloc context!\n");
 529                 return -1;
 530         }
 531
 532         /* set default debug level to 1 regardless of what smb.conf sets */
 533         setup_logging( "sharesec", True );
 534         DEBUGLEVEL_CLASS[DBGC_ALL] = 1;
 535         dbf = x_stderr;
 536         x_setbuf( x_stderr, NULL );
 537
 538         pc = poptGetContext("sharesec", argc, argv, long_options, 0);
 539
 540         poptSetOtherOptionHelp(pc, "sharename\n");
 541
 542         while ((opt = poptGetNextOpt(pc)) != -1) {
 543                 switch (opt) {
 544                 case 'r':
 545                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 546                         mode = SMB_ACL_DELETE;
 547                         break;
 548
 549                 case 'm':
 550                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 551                         mode = SMB_ACL_MODIFY;
 552                         break;
 553
 554                 case 'a':
 555                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 556                         mode = SMB_ACL_ADD;
 557                         break;
 558                 case 'R':
 559                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 560                         mode = SMB_ACL_SET;
 561                         break;
 562
 563                 case 'v':
 564                         mode = SMB_ACL_VIEW;
 565                         break;
 566
 567                 case 'F':
 568                         force_acl = True;
 569                         break;
 570
 571                 case 'M':
 572                         initialize_sid = True;
 573                         break;
 574                 }
 575         }
 576
 577         setlinebuf(stdout);
 578
 579         load_case_tables();
 580
 581         lp_load( get_dyn_CONFIGFILE(), False, False, False, True );
 582
 583         /* check for initializing secrets.tdb first */
 584
 585         if ( initialize_sid ) {
 586                 DOM_SID *sid = get_global_sam_sid();
 587
 588                 if ( !sid ) {
 589                         fprintf( stderr, "Failed to retrieve Machine SID!\n");
 590                         return 3;
 591                 }
 592
 593                 printf ("%s\n", sid_string_tos( sid ) );
 594                 return 0;
 595         }
 596
 597         if ( mode == SMB_ACL_VIEW && force_acl ) {
 598                 fprintf( stderr, "Invalid combination of -F and -v\n");
 599                 return -1;
 600         }
 601
 602         /* get the sharename */
 603
 604         if(!poptPeekArg(pc)) {
 605                 poptPrintUsage(pc, stderr, 0);
 606                 return -1;
 607         }
 608
 609         fstrcpy(sharename, poptGetArg(pc));
 610
 611         snum = lp_servicenumber( sharename );
 612
 613         if ( snum == -1 && !force_acl ) {
 614                 fprintf( stderr, "Invalid sharename: %s\n", sharename);
 615                 return -1;
 616         }
 617
 618         retval = change_share_sec(ctx, sharename, the_acl, mode);
 619
 620         talloc_destroy(ctx);
 621
 622         return retval;
 623 }