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_SD_DELETE,
  34                 SMB_ACL_VIEW };
  35
  36 struct perm_value {
  37         const char *perm;
  38         uint32 mask;
  39 };
  40
  41 /* These values discovered by inspection */
  42
  43 static const struct perm_value special_values[] = {
  44         { "R", SEC_RIGHTS_FILE_READ },
  45         { "W", SEC_RIGHTS_FILE_WRITE },
  46         { "X", SEC_RIGHTS_FILE_EXECUTE },
  47         { "D", SEC_STD_DELETE },
  48         { "P", SEC_STD_WRITE_DAC },
  49         { "O", SEC_STD_WRITE_OWNER },
  50         { NULL, 0 },
  51 };
  52
  53 #define SEC_RIGHTS_DIR_CHANGE ( SEC_RIGHTS_DIR_READ|SEC_STD_DELETE|\
  54                                 SEC_RIGHTS_DIR_WRITE|SEC_DIR_TRAVERSE )
  55
  56 static const struct perm_value standard_values[] = {
  57         { "READ",   SEC_RIGHTS_DIR_READ|SEC_DIR_TRAVERSE },
  58         { "CHANGE", SEC_RIGHTS_DIR_CHANGE },
  59         { "FULL",   SEC_RIGHTS_DIR_ALL },
  60         { NULL, 0 },
  61 };
  62
  63 /********************************************************************
  64  print an ACE on a FILE
  65 ********************************************************************/
  66
  67 static void print_ace(FILE *f, SEC_ACE *ace)
  68 {
  69         const struct perm_value *v;
  70         int do_print = 0;
  71         uint32 got_mask;
  72
  73         fprintf(f, "%s:", sid_string_tos(&ace->trustee));
  74
  75         /* Ace type */
  76
  77         if (ace->type == SEC_ACE_TYPE_ACCESS_ALLOWED) {
  78                 fprintf(f, "ALLOWED");
  79         } else if (ace->type == SEC_ACE_TYPE_ACCESS_DENIED) {
  80                 fprintf(f, "DENIED");
  81         } else {
  82                 fprintf(f, "%d", ace->type);
  83         }
  84
  85         /* Not sure what flags can be set in a file ACL */
  86
  87         fprintf(f, "/%d/", ace->flags);
  88
  89         /* Standard permissions */
  90
  91         for (v = standard_values; v->perm; v++) {
  92                 if (ace->access_mask == v->mask) {
  93                         fprintf(f, "%s", v->perm);
  94                         return;
  95                 }
  96         }
  97
  98         /* Special permissions.  Print out a hex value if we have
  99            leftover bits in the mask. */
 100
 101         got_mask = ace->access_mask;
 102
 103  again:
 104         for (v = special_values; v->perm; v++) {
 105                 if ((ace->access_mask & v->mask) == v->mask) {
 106                         if (do_print) {
 107                                 fprintf(f, "%s", v->perm);
 108                         }
 109                         got_mask &= ~v->mask;
 110                 }
 111         }
 112
 113         if (!do_print) {
 114                 if (got_mask != 0) {
 115                         fprintf(f, "0x%08x", ace->access_mask);
 116                 } else {
 117                         do_print = 1;
 118                         goto again;
 119                 }
 120         }
 121 }
 122
 123 /********************************************************************
 124  print an ascii version of a security descriptor on a FILE handle
 125 ********************************************************************/
 126
 127 static void sec_desc_print(FILE *f, SEC_DESC *sd)
 128 {
 129         uint32 i;
 130
 131         fprintf(f, "REVISION:%d\n", sd->revision);
 132
 133         /* Print owner and group sid */
 134
 135         fprintf(f, "OWNER:%s\n", sid_string_tos(sd->owner_sid));
 136
 137         fprintf(f, "GROUP:%s\n", sid_string_tos(sd->group_sid));
 138
 139         /* Print aces */
 140         for (i = 0; sd->dacl && i < sd->dacl->num_aces; i++) {
 141                 SEC_ACE *ace = &sd->dacl->aces[i];
 142                 fprintf(f, "ACL:");
 143                 print_ace(f, ace);
 144                 fprintf(f, "\n");
 145         }
 146 }
 147
 148 /********************************************************************
 149  parse an ACE in the same format as print_ace()
 150 ********************************************************************/
 151
 152 static bool parse_ace(SEC_ACE *ace, const char *orig_str)
 153 {
 154         char *p;
 155         const char *cp;
 156         char *tok;
 157         unsigned int atype = 0;
 158         unsigned int aflags = 0;
 159         unsigned int amask = 0;
 160         DOM_SID sid;
 161         uint32_t mask;
 162         const struct perm_value *v;
 163         char *str = SMB_STRDUP(orig_str);
 164         TALLOC_CTX *frame = talloc_stackframe();
 165
 166         if (!str) {
 167                 TALLOC_FREE(frame);
 168                 return False;
 169         }
 170
 171         ZERO_STRUCTP(ace);
 172         p = strchr_m(str,':');
 173         if (!p) {
 174                 fprintf(stderr, "ACE '%s': missing ':'.\n", orig_str);
 175                 SAFE_FREE(str);
 176                 TALLOC_FREE(frame);
 177                 return False;
 178         }
 179         *p = '\0';
 180         p++;
 181         /* Try to parse numeric form */
 182
 183         if (sscanf(p, "%i/%i/%i", &atype, &aflags, &amask) == 3 &&
 184             string_to_sid(&sid, str)) {
 185                 goto done;
 186         }
 187
 188         /* Try to parse text form */
 189
 190         if (!string_to_sid(&sid, str)) {
 191                 fprintf(stderr, "ACE '%s': failed to convert '%s' to SID\n",
 192                         orig_str, str);
 193                 SAFE_FREE(str);
 194                 TALLOC_FREE(frame);
 195                 return False;
 196         }
 197
 198         cp = p;
 199         if (!next_token_talloc(frame, &cp, &tok, "/")) {
 200                 fprintf(stderr, "ACE '%s': failed to find '/' character.\n",
 201                         orig_str);
 202                 SAFE_FREE(str);
 203                 TALLOC_FREE(frame);
 204                 return False;
 205         }
 206
 207         if (strncmp(tok, "ALLOWED", strlen("ALLOWED")) == 0) {
 208                 atype = SEC_ACE_TYPE_ACCESS_ALLOWED;
 209         } else if (strncmp(tok, "DENIED", strlen("DENIED")) == 0) {
 210                 atype = SEC_ACE_TYPE_ACCESS_DENIED;
 211         } else {
 212                 fprintf(stderr, "ACE '%s': missing 'ALLOWED' or 'DENIED' "
 213                         "entry at '%s'\n", orig_str, tok);
 214                 SAFE_FREE(str);
 215                 TALLOC_FREE(frame);
 216                 return False;
 217         }
 218
 219         /* Only numeric form accepted for flags at present */
 220         /* no flags on share permissions */
 221
 222         if (!(next_token_talloc(frame, &cp, &tok, "/") &&
 223               sscanf(tok, "%i", &aflags) && aflags == 0)) {
 224                 fprintf(stderr, "ACE '%s': bad integer flags entry at '%s'\n",
 225                         orig_str, tok);
 226                 SAFE_FREE(str);
 227                 TALLOC_FREE(frame);
 228                 return False;
 229         }
 230
 231         if (!next_token_talloc(frame, &cp, &tok, "/")) {
 232                 fprintf(stderr, "ACE '%s': missing / at '%s'\n",
 233                         orig_str, tok);
 234                 SAFE_FREE(str);
 235                 TALLOC_FREE(frame);
 236                 return False;
 237         }
 238
 239         if (strncmp(tok, "0x", 2) == 0) {
 240                 if (sscanf(tok, "%i", &amask) != 1) {
 241                         fprintf(stderr, "ACE '%s': bad hex number at '%s'\n",
 242                                 orig_str, tok);
 243                         TALLOC_FREE(frame);
 244                         SAFE_FREE(str);
 245                         return False;
 246                 }
 247                 goto done;
 248         }
 249
 250         for (v = standard_values; v->perm; v++) {
 251                 if (strcmp(tok, v->perm) == 0) {
 252                         amask = v->mask;
 253                         goto done;
 254                 }
 255         }
 256
 257         p = tok;
 258
 259         while(*p) {
 260                 bool found = False;
 261
 262                 for (v = special_values; v->perm; v++) {
 263                         if (v->perm[0] == *p) {
 264                                 amask |= v->mask;
 265                                 found = True;
 266                         }
 267                 }
 268
 269                 if (!found) {
 270                         fprintf(stderr, "ACE '%s': bad permission value at "
 271                                 "'%s'\n", orig_str, p);
 272                         TALLOC_FREE(frame);
 273                         SAFE_FREE(str);
 274                         return False;
 275                 }
 276                 p++;
 277         }
 278
 279         if (*p) {
 280                 TALLOC_FREE(frame);
 281                 SAFE_FREE(str);
 282                 return False;
 283         }
 284
 285  done:
 286         mask = amask;
 287         init_sec_ace(ace, &sid, atype, mask, aflags);
 288         SAFE_FREE(str);
 289         TALLOC_FREE(frame);
 290         return True;
 291 }
 292
 293
 294 /********************************************************************
 295 ********************************************************************/
 296
 297 static SEC_DESC* parse_acl_string(TALLOC_CTX *mem_ctx, const char *szACL, size_t *sd_size )
 298 {
 299         SEC_DESC *sd = NULL;
 300         SEC_ACE *ace;
 301         SEC_ACL *theacl;
 302         int num_ace;
 303         const char *pacl;
 304         int i;
 305
 306         if ( !szACL )
 307                 return NULL;
 308
 309         pacl = szACL;
 310         num_ace = count_chars( pacl, ',' ) + 1;
 311
 312         if ( !(ace = TALLOC_ZERO_ARRAY( mem_ctx, SEC_ACE, num_ace )) )
 313                 return NULL;
 314
 315         for ( i=0; i<num_ace; i++ ) {
 316                 char *end_acl = strchr_m( pacl, ',' );
 317                 fstring acl_string;
 318
 319                 strncpy( acl_string, pacl, MIN( PTR_DIFF( end_acl, pacl ), sizeof(fstring)-1) );
 320                 acl_string[MIN( PTR_DIFF( end_acl, pacl ), sizeof(fstring)-1)] = '\0';
 321
 322                 if ( !parse_ace( &ace[i], acl_string ) )
 323                         return NULL;
 324
 325                 pacl = end_acl;
 326                 pacl++;
 327         }
 328
 329         if ( !(theacl = make_sec_acl( mem_ctx, NT4_ACL_REVISION, num_ace, ace )) )
 330                 return NULL;
 331
 332         sd = make_sec_desc( mem_ctx, SEC_DESC_REVISION, SEC_DESC_SELF_RELATIVE,
 333                 NULL, NULL, NULL, theacl, sd_size);
 334
 335         return sd;
 336 }
 337
 338 /* add an ACE to a list of ACEs in a SEC_ACL */
 339 static bool add_ace(TALLOC_CTX *mem_ctx, SEC_ACL **the_acl, SEC_ACE *ace)
 340 {
 341         SEC_ACL *new_ace;
 342         SEC_ACE *aces;
 343         if (! *the_acl) {
 344                 return (((*the_acl) = make_sec_acl(mem_ctx, 3, 1, ace)) != NULL);
 345         }
 346
 347         if (!(aces = SMB_CALLOC_ARRAY(SEC_ACE, 1+(*the_acl)->num_aces))) {
 348                 return False;
 349         }
 350         memcpy(aces, (*the_acl)->aces, (*the_acl)->num_aces * sizeof(SEC_ACE));
 351         memcpy(aces+(*the_acl)->num_aces, ace, sizeof(SEC_ACE));
 352         new_ace = make_sec_acl(mem_ctx,(*the_acl)->revision,1+(*the_acl)->num_aces, aces);
 353         SAFE_FREE(aces);
 354         (*the_acl) = new_ace;
 355         return True;
 356 }
 357
 358 /* The MSDN is contradictory over the ordering of ACE entries in an ACL.
 359    However NT4 gives a "The information may have been modified by a
 360    computer running Windows NT 5.0" if denied ACEs do not appear before
 361    allowed ACEs. */
 362
 363 static int ace_compare(SEC_ACE *ace1, SEC_ACE *ace2)
 364 {
 365         if (sec_ace_equal(ace1, ace2))
 366                 return 0;
 367
 368         if (ace1->type != ace2->type)
 369                 return ace2->type - ace1->type;
 370
 371         if (sid_compare(&ace1->trustee, &ace2->trustee))
 372                 return sid_compare(&ace1->trustee, &ace2->trustee);
 373
 374         if (ace1->flags != ace2->flags)
 375                 return ace1->flags - ace2->flags;
 376
 377         if (ace1->access_mask != ace2->access_mask)
 378                 return ace1->access_mask - ace2->access_mask;
 379
 380         if (ace1->size != ace2->size)
 381                 return ace1->size - ace2->size;
 382
 383         return memcmp(ace1, ace2, sizeof(SEC_ACE));
 384 }
 385
 386 static void sort_acl(SEC_ACL *the_acl)
 387 {
 388         uint32 i;
 389         if (!the_acl) return;
 390
 391         qsort(the_acl->aces, the_acl->num_aces, sizeof(the_acl->aces[0]), QSORT_CAST ace_compare);
 392
 393         for (i=1;i<the_acl->num_aces;) {
 394                 if (sec_ace_equal(&the_acl->aces[i-1], &the_acl->aces[i])) {
 395                         int j;
 396                         for (j=i; j<the_acl->num_aces-1; j++) {
 397                                 the_acl->aces[j] = the_acl->aces[j+1];
 398                         }
 399                         the_acl->num_aces--;
 400                 } else {
 401                         i++;
 402                 }
 403         }
 404 }
 405
 406
 407 static int change_share_sec(TALLOC_CTX *mem_ctx, const char *sharename, char *the_acl, enum acl_mode mode)
 408 {
 409         SEC_DESC *sd = NULL;
 410         SEC_DESC *old = NULL;
 411         size_t sd_size = 0;
 412         uint32 i, j;
 413
 414         if (mode != SMB_ACL_SET && mode != SMB_SD_DELETE) {
 415             if (!(old = get_share_security( mem_ctx, sharename, &sd_size )) ) {
 416                 fprintf(stderr, "Unable to retrieve permissions for share "
 417                         "[%s]\n", sharename);
 418                 return -1;
 419             }
 420         }
 421
 422         if ( (mode != SMB_ACL_VIEW && mode != SMB_SD_DELETE) &&
 423             !(sd = parse_acl_string(mem_ctx, the_acl, &sd_size )) ) {
 424                 fprintf( stderr, "Failed to parse acl\n");
 425                 return -1;
 426         }
 427
 428         switch (mode) {
 429         case SMB_ACL_VIEW:
 430                 sec_desc_print( stdout, old);
 431                 return 0;
 432         case SMB_ACL_DELETE:
 433             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 434                 bool found = False;
 435
 436                 for (j=0;old->dacl && j<old->dacl->num_aces;j++) {
 437                     if (sec_ace_equal(&sd->dacl->aces[i], &old->dacl->aces[j])) {
 438                         uint32 k;
 439                         for (k=j; k<old->dacl->num_aces-1;k++) {
 440                             old->dacl->aces[k] = old->dacl->aces[k+1];
 441                         }
 442                         old->dacl->num_aces--;
 443                         found = True;
 444                         break;
 445                     }
 446                 }
 447
 448                 if (!found) {
 449                 printf("ACL for ACE:");
 450                 print_ace(stdout, &sd->dacl->aces[i]);
 451                 printf(" not found\n");
 452                 }
 453             }
 454             break;
 455         case SMB_ACL_MODIFY:
 456             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 457                 bool found = False;
 458
 459                 for (j=0;old->dacl && j<old->dacl->num_aces;j++) {
 460                     if (sid_equal(&sd->dacl->aces[i].trustee,
 461                         &old->dacl->aces[j].trustee)) {
 462                         old->dacl->aces[j] = sd->dacl->aces[i];
 463                         found = True;
 464                     }
 465                 }
 466
 467                 if (!found) {
 468                     printf("ACL for SID %s not found\n",
 469                            sid_string_tos(&sd->dacl->aces[i].trustee));
 470                 }
 471             }
 472
 473             if (sd->owner_sid) {
 474                 old->owner_sid = sd->owner_sid;
 475             }
 476
 477             if (sd->group_sid) {
 478                 old->group_sid = sd->group_sid;
 479             }
 480             break;
 481         case SMB_ACL_ADD:
 482             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 483                 add_ace(mem_ctx, &old->dacl, &sd->dacl->aces[i]);
 484             }
 485             break;
 486         case SMB_ACL_SET:
 487             old = sd;
 488             break;
 489         case SMB_SD_DELETE:
 490             if (!delete_share_security(sharename)) {
 491                 fprintf( stderr, "Failed to delete security descriptor for "
 492                          "share [%s]\n", sharename );
 493                 return -1;
 494             }
 495             return 0;
 496         }
 497
 498         /* Denied ACE entries must come before allowed ones */
 499         sort_acl(old->dacl);
 500
 501         if ( !set_share_security( sharename, old ) ) {
 502             fprintf( stderr, "Failed to store acl for share [%s]\n", sharename );
 503             return 2;
 504         }
 505         return 0;
 506 }
 507
 508 /********************************************************************
 509   main program
 510 ********************************************************************/
 511
 512 int main(int argc, const char *argv[])
 513 {
 514         int opt;
 515         int retval = 0;
 516         enum acl_mode mode = SMB_ACL_SET;
 517         static char *the_acl = NULL;
 518         fstring sharename;
 519         bool force_acl = False;
 520         int snum;
 521         poptContext pc;
 522         bool initialize_sid = False;
 523         struct poptOption long_options[] = {
 524                 POPT_AUTOHELP
 525                 { "remove", 'r', POPT_ARG_STRING, &the_acl, 'r', "Remove ACEs", "ACL" },
 526                 { "modify", 'm', POPT_ARG_STRING, &the_acl, 'm', "Modify existing ACEs", "ACL" },
 527                 { "add", 'a', POPT_ARG_STRING, &the_acl, 'a', "Add ACEs", "ACL" },
 528                 { "replace", 'R', POPT_ARG_STRING, &the_acl, 'R', "Overwrite share permission ACL", "ACLS" },
 529                 { "delete", 'D', POPT_ARG_NONE, NULL, 'D', "Delete the entire security descriptor" },
 530                 { "view", 'v', POPT_ARG_NONE, NULL, 'v', "View current share permissions" },
 531                 { "machine-sid", 'M', POPT_ARG_NONE, NULL, 'M', "Initialize the machine SID" },
 532                 { "force", 'F', POPT_ARG_NONE, NULL, 'F', "Force storing the ACL", "ACLS" },
 533                 POPT_COMMON_SAMBA
 534                 { NULL }
 535         };
 536
 537         if ( !(ctx = talloc_stackframe()) ) {
 538                 fprintf( stderr, "Failed to initialize talloc context!\n");
 539                 return -1;
 540         }
 541
 542         /* set default debug level to 1 regardless of what smb.conf sets */
 543         setup_logging( "sharesec", True );
 544         DEBUGLEVEL_CLASS[DBGC_ALL] = 1;
 545         dbf = x_stderr;
 546         x_setbuf( x_stderr, NULL );
 547
 548         pc = poptGetContext("sharesec", argc, argv, long_options, 0);
 549
 550         poptSetOtherOptionHelp(pc, "sharename\n");
 551
 552         while ((opt = poptGetNextOpt(pc)) != -1) {
 553                 switch (opt) {
 554                 case 'r':
 555                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 556                         mode = SMB_ACL_DELETE;
 557                         break;
 558
 559                 case 'm':
 560                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 561                         mode = SMB_ACL_MODIFY;
 562                         break;
 563
 564                 case 'a':
 565                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 566                         mode = SMB_ACL_ADD;
 567                         break;
 568
 569                 case 'R':
 570                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 571                         mode = SMB_ACL_SET;
 572                         break;
 573
 574                 case 'D':
 575                         mode = SMB_SD_DELETE;
 576                         break;
 577
 578                 case 'v':
 579                         mode = SMB_ACL_VIEW;
 580                         break;
 581
 582                 case 'F':
 583                         force_acl = True;
 584                         break;
 585
 586                 case 'M':
 587                         initialize_sid = True;
 588                         break;
 589                 }
 590         }
 591
 592         setlinebuf(stdout);
 593
 594         load_case_tables();
 595
 596         lp_load( get_dyn_CONFIGFILE(), False, False, False, True );
 597
 598         /* check for initializing secrets.tdb first */
 599
 600         if ( initialize_sid ) {
 601                 DOM_SID *sid = get_global_sam_sid();
 602
 603                 if ( !sid ) {
 604                         fprintf( stderr, "Failed to retrieve Machine SID!\n");
 605                         return 3;
 606                 }
 607
 608                 printf ("%s\n", sid_string_tos( sid ) );
 609                 return 0;
 610         }
 611
 612         if ( mode == SMB_ACL_VIEW && force_acl ) {
 613                 fprintf( stderr, "Invalid combination of -F and -v\n");
 614                 return -1;
 615         }
 616
 617         /* get the sharename */
 618
 619         if(!poptPeekArg(pc)) {
 620                 poptPrintUsage(pc, stderr, 0);
 621                 return -1;
 622         }
 623
 624         fstrcpy(sharename, poptGetArg(pc));
 625
 626         snum = lp_servicenumber( sharename );
 627
 628         if ( snum == -1 && !force_acl ) {
 629                 fprintf( stderr, "Invalid sharename: %s\n", sharename);
 630                 return -1;
 631         }
 632
 633         retval = change_share_sec(ctx, sharename, the_acl, mode);
 634
 635         talloc_destroy(ctx);
 636
 637         return retval;
 638 }