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 #include "popt_common.h"
  27 #include "../libcli/security/security.h"
  28 #include "passdb/machine_sid.h"
  29
  30 static TALLOC_CTX *ctx;
  31
  32 enum acl_mode { SMB_ACL_DELETE,
  33                 SMB_ACL_MODIFY,
  34                 SMB_ACL_ADD,
  35                 SMB_ACL_SET,
  36                 SMB_SD_DELETE,
  37                 SMB_ACL_VIEW };
  38
  39 struct perm_value {
  40         const char *perm;
  41         uint32 mask;
  42 };
  43
  44 /* These values discovered by inspection */
  45
  46 static const struct perm_value special_values[] = {
  47         { "R", SEC_RIGHTS_FILE_READ },
  48         { "W", SEC_RIGHTS_FILE_WRITE },
  49         { "X", SEC_RIGHTS_FILE_EXECUTE },
  50         { "D", SEC_STD_DELETE },
  51         { "P", SEC_STD_WRITE_DAC },
  52         { "O", SEC_STD_WRITE_OWNER },
  53         { NULL, 0 },
  54 };
  55
  56 #define SEC_RIGHTS_DIR_CHANGE ( SEC_RIGHTS_DIR_READ|SEC_STD_DELETE|\
  57                                 SEC_RIGHTS_DIR_WRITE|SEC_DIR_TRAVERSE )
  58
  59 static const struct perm_value standard_values[] = {
  60         { "READ",   SEC_RIGHTS_DIR_READ|SEC_DIR_TRAVERSE },
  61         { "CHANGE", SEC_RIGHTS_DIR_CHANGE },
  62         { "FULL",   SEC_RIGHTS_DIR_ALL },
  63         { NULL, 0 },
  64 };
  65
  66 /********************************************************************
  67  print an ACE on a FILE
  68 ********************************************************************/
  69
  70 static void print_ace(FILE *f, struct security_ace *ace)
  71 {
  72         const struct perm_value *v;
  73         int do_print = 0;
  74         uint32 got_mask;
  75
  76         fprintf(f, "%s:", sid_string_tos(&ace->trustee));
  77
  78         /* Ace type */
  79
  80         if (ace->type == SEC_ACE_TYPE_ACCESS_ALLOWED) {
  81                 fprintf(f, "ALLOWED");
  82         } else if (ace->type == SEC_ACE_TYPE_ACCESS_DENIED) {
  83                 fprintf(f, "DENIED");
  84         } else {
  85                 fprintf(f, "%d", ace->type);
  86         }
  87
  88         /* Not sure what flags can be set in a file ACL */
  89
  90         fprintf(f, "/%d/", ace->flags);
  91
  92         /* Standard permissions */
  93
  94         for (v = standard_values; v->perm; v++) {
  95                 if (ace->access_mask == v->mask) {
  96                         fprintf(f, "%s", v->perm);
  97                         return;
  98                 }
  99         }
 100
 101         /* Special permissions.  Print out a hex value if we have
 102            leftover bits in the mask. */
 103
 104         got_mask = ace->access_mask;
 105
 106  again:
 107         for (v = special_values; v->perm; v++) {
 108                 if ((ace->access_mask & v->mask) == v->mask) {
 109                         if (do_print) {
 110                                 fprintf(f, "%s", v->perm);
 111                         }
 112                         got_mask &= ~v->mask;
 113                 }
 114         }
 115
 116         if (!do_print) {
 117                 if (got_mask != 0) {
 118                         fprintf(f, "0x%08x", ace->access_mask);
 119                 } else {
 120                         do_print = 1;
 121                         goto again;
 122                 }
 123         }
 124 }
 125
 126 /********************************************************************
 127  print an ascii version of a security descriptor on a FILE handle
 128 ********************************************************************/
 129
 130 static void sec_desc_print(FILE *f, struct security_descriptor *sd)
 131 {
 132         uint32 i;
 133
 134         fprintf(f, "REVISION:%d\n", sd->revision);
 135
 136         /* Print owner and group sid */
 137
 138         fprintf(f, "OWNER:%s\n", sid_string_tos(sd->owner_sid));
 139
 140         fprintf(f, "GROUP:%s\n", sid_string_tos(sd->group_sid));
 141
 142         /* Print aces */
 143         for (i = 0; sd->dacl && i < sd->dacl->num_aces; i++) {
 144                 struct security_ace *ace = &sd->dacl->aces[i];
 145                 fprintf(f, "ACL:");
 146                 print_ace(f, ace);
 147                 fprintf(f, "\n");
 148         }
 149 }
 150
 151 /********************************************************************
 152  parse an ACE in the same format as print_ace()
 153 ********************************************************************/
 154
 155 static bool parse_ace(struct security_ace *ace, const char *orig_str)
 156 {
 157         char *p;
 158         const char *cp;
 159         char *tok;
 160         unsigned int atype = 0;
 161         unsigned int aflags = 0;
 162         unsigned int amask = 0;
 163         struct dom_sid sid;
 164         uint32_t mask;
 165         const struct perm_value *v;
 166         char *str = SMB_STRDUP(orig_str);
 167         TALLOC_CTX *frame = talloc_stackframe();
 168
 169         if (!str) {
 170                 TALLOC_FREE(frame);
 171                 return False;
 172         }
 173
 174         ZERO_STRUCTP(ace);
 175         p = strchr_m(str,':');
 176         if (!p) {
 177                 fprintf(stderr, "ACE '%s': missing ':'.\n", orig_str);
 178                 SAFE_FREE(str);
 179                 TALLOC_FREE(frame);
 180                 return False;
 181         }
 182         *p = '\0';
 183         p++;
 184         /* Try to parse numeric form */
 185
 186         if (sscanf(p, "%i/%i/%i", &atype, &aflags, &amask) == 3 &&
 187             string_to_sid(&sid, str)) {
 188                 goto done;
 189         }
 190
 191         /* Try to parse text form */
 192
 193         if (!string_to_sid(&sid, str)) {
 194                 fprintf(stderr, "ACE '%s': failed to convert '%s' to SID\n",
 195                         orig_str, str);
 196                 SAFE_FREE(str);
 197                 TALLOC_FREE(frame);
 198                 return False;
 199         }
 200
 201         cp = p;
 202         if (!next_token_talloc(frame, &cp, &tok, "/")) {
 203                 fprintf(stderr, "ACE '%s': failed to find '/' character.\n",
 204                         orig_str);
 205                 SAFE_FREE(str);
 206                 TALLOC_FREE(frame);
 207                 return False;
 208         }
 209
 210         if (strncmp(tok, "ALLOWED", strlen("ALLOWED")) == 0) {
 211                 atype = SEC_ACE_TYPE_ACCESS_ALLOWED;
 212         } else if (strncmp(tok, "DENIED", strlen("DENIED")) == 0) {
 213                 atype = SEC_ACE_TYPE_ACCESS_DENIED;
 214         } else {
 215                 fprintf(stderr, "ACE '%s': missing 'ALLOWED' or 'DENIED' "
 216                         "entry at '%s'\n", orig_str, tok);
 217                 SAFE_FREE(str);
 218                 TALLOC_FREE(frame);
 219                 return False;
 220         }
 221
 222         /* Only numeric form accepted for flags at present */
 223         /* no flags on share permissions */
 224
 225         if (!(next_token_talloc(frame, &cp, &tok, "/") &&
 226               sscanf(tok, "%i", &aflags) && aflags == 0)) {
 227                 fprintf(stderr, "ACE '%s': bad integer flags entry at '%s'\n",
 228                         orig_str, tok);
 229                 SAFE_FREE(str);
 230                 TALLOC_FREE(frame);
 231                 return False;
 232         }
 233
 234         if (!next_token_talloc(frame, &cp, &tok, "/")) {
 235                 fprintf(stderr, "ACE '%s': missing / at '%s'\n",
 236                         orig_str, tok);
 237                 SAFE_FREE(str);
 238                 TALLOC_FREE(frame);
 239                 return False;
 240         }
 241
 242         if (strncmp(tok, "0x", 2) == 0) {
 243                 if (sscanf(tok, "%i", &amask) != 1) {
 244                         fprintf(stderr, "ACE '%s': bad hex number at '%s'\n",
 245                                 orig_str, tok);
 246                         TALLOC_FREE(frame);
 247                         SAFE_FREE(str);
 248                         return False;
 249                 }
 250                 goto done;
 251         }
 252
 253         for (v = standard_values; v->perm; v++) {
 254                 if (strcmp(tok, v->perm) == 0) {
 255                         amask = v->mask;
 256                         goto done;
 257                 }
 258         }
 259
 260         p = tok;
 261
 262         while(*p) {
 263                 bool found = False;
 264
 265                 for (v = special_values; v->perm; v++) {
 266                         if (v->perm[0] == *p) {
 267                                 amask |= v->mask;
 268                                 found = True;
 269                         }
 270                 }
 271
 272                 if (!found) {
 273                         fprintf(stderr, "ACE '%s': bad permission value at "
 274                                 "'%s'\n", orig_str, p);
 275                         TALLOC_FREE(frame);
 276                         SAFE_FREE(str);
 277                         return False;
 278                 }
 279                 p++;
 280         }
 281
 282         if (*p) {
 283                 TALLOC_FREE(frame);
 284                 SAFE_FREE(str);
 285                 return False;
 286         }
 287
 288  done:
 289         mask = amask;
 290         init_sec_ace(ace, &sid, atype, mask, aflags);
 291         SAFE_FREE(str);
 292         TALLOC_FREE(frame);
 293         return True;
 294 }
 295
 296
 297 /********************************************************************
 298 ********************************************************************/
 299
 300 static struct security_descriptor* parse_acl_string(TALLOC_CTX *mem_ctx, const char *szACL, size_t *sd_size )
 301 {
 302         struct security_descriptor *sd = NULL;
 303         struct security_ace *ace;
 304         struct security_acl *theacl;
 305         int num_ace;
 306         const char *pacl;
 307         int i;
 308
 309         if ( !szACL )
 310                 return NULL;
 311
 312         pacl = szACL;
 313         num_ace = count_chars( pacl, ',' ) + 1;
 314
 315         if ( !(ace = talloc_zero_array( mem_ctx, struct security_ace, num_ace )) )
 316                 return NULL;
 317
 318         for ( i=0; i<num_ace; i++ ) {
 319                 char *end_acl = strchr_m( pacl, ',' );
 320                 fstring acl_string;
 321
 322                 strncpy( acl_string, pacl, MIN( PTR_DIFF( end_acl, pacl ), sizeof(fstring)-1) );
 323                 acl_string[MIN( PTR_DIFF( end_acl, pacl ), sizeof(fstring)-1)] = '\0';
 324
 325                 if ( !parse_ace( &ace[i], acl_string ) )
 326                         return NULL;
 327
 328                 pacl = end_acl;
 329                 pacl++;
 330         }
 331
 332         if ( !(theacl = make_sec_acl( mem_ctx, NT4_ACL_REVISION, num_ace, ace )) )
 333                 return NULL;
 334
 335         sd = make_sec_desc( mem_ctx, SD_REVISION, SEC_DESC_SELF_RELATIVE,
 336                 NULL, NULL, NULL, theacl, sd_size);
 337
 338         return sd;
 339 }
 340
 341 /* add an ACE to a list of ACEs in a struct security_acl */
 342 static bool add_ace(TALLOC_CTX *mem_ctx, struct security_acl **the_acl, struct security_ace *ace)
 343 {
 344         struct security_acl *new_ace;
 345         struct security_ace *aces;
 346         if (! *the_acl) {
 347                 return (((*the_acl) = make_sec_acl(mem_ctx, 3, 1, ace)) != NULL);
 348         }
 349
 350         if (!(aces = SMB_CALLOC_ARRAY(struct security_ace, 1+(*the_acl)->num_aces))) {
 351                 return False;
 352         }
 353         memcpy(aces, (*the_acl)->aces, (*the_acl)->num_aces * sizeof(struct
 354         security_ace));
 355         memcpy(aces+(*the_acl)->num_aces, ace, sizeof(struct security_ace));
 356         new_ace = make_sec_acl(mem_ctx,(*the_acl)->revision,1+(*the_acl)->num_aces, aces);
 357         SAFE_FREE(aces);
 358         (*the_acl) = new_ace;
 359         return True;
 360 }
 361
 362 /* The MSDN is contradictory over the ordering of ACE entries in an ACL.
 363    However NT4 gives a "The information may have been modified by a
 364    computer running Windows NT 5.0" if denied ACEs do not appear before
 365    allowed ACEs. */
 366
 367 static int ace_compare(struct security_ace *ace1, struct security_ace *ace2)
 368 {
 369         if (sec_ace_equal(ace1, ace2))
 370                 return 0;
 371
 372         if (ace1->type != ace2->type)
 373                 return ace2->type - ace1->type;
 374
 375         if (dom_sid_compare(&ace1->trustee, &ace2->trustee))
 376                 return dom_sid_compare(&ace1->trustee, &ace2->trustee);
 377
 378         if (ace1->flags != ace2->flags)
 379                 return ace1->flags - ace2->flags;
 380
 381         if (ace1->access_mask != ace2->access_mask)
 382                 return ace1->access_mask - ace2->access_mask;
 383
 384         if (ace1->size != ace2->size)
 385                 return ace1->size - ace2->size;
 386
 387         return memcmp(ace1, ace2, sizeof(struct security_ace));
 388 }
 389
 390 static void sort_acl(struct security_acl *the_acl)
 391 {
 392         uint32 i;
 393         if (!the_acl) return;
 394
 395         TYPESAFE_QSORT(the_acl->aces, the_acl->num_aces, ace_compare);
 396
 397         for (i=1;i<the_acl->num_aces;) {
 398                 if (sec_ace_equal(&the_acl->aces[i-1], &the_acl->aces[i])) {
 399                         int j;
 400                         for (j=i; j<the_acl->num_aces-1; j++) {
 401                                 the_acl->aces[j] = the_acl->aces[j+1];
 402                         }
 403                         the_acl->num_aces--;
 404                 } else {
 405                         i++;
 406                 }
 407         }
 408 }
 409
 410
 411 static int change_share_sec(TALLOC_CTX *mem_ctx, const char *sharename, char *the_acl, enum acl_mode mode)
 412 {
 413         struct security_descriptor *sd = NULL;
 414         struct security_descriptor *old = NULL;
 415         size_t sd_size = 0;
 416         uint32 i, j;
 417
 418         if (mode != SMB_ACL_SET && mode != SMB_SD_DELETE) {
 419             if (!(old = get_share_security( mem_ctx, sharename, &sd_size )) ) {
 420                 fprintf(stderr, "Unable to retrieve permissions for share "
 421                         "[%s]\n", sharename);
 422                 return -1;
 423             }
 424         }
 425
 426         if ( (mode != SMB_ACL_VIEW && mode != SMB_SD_DELETE) &&
 427             !(sd = parse_acl_string(mem_ctx, the_acl, &sd_size )) ) {
 428                 fprintf( stderr, "Failed to parse acl\n");
 429                 return -1;
 430         }
 431
 432         switch (mode) {
 433         case SMB_ACL_VIEW:
 434                 sec_desc_print( stdout, old);
 435                 return 0;
 436         case SMB_ACL_DELETE:
 437             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 438                 bool found = False;
 439
 440                 for (j=0;old->dacl && j<old->dacl->num_aces;j++) {
 441                     if (sec_ace_equal(&sd->dacl->aces[i], &old->dacl->aces[j])) {
 442                         uint32 k;
 443                         for (k=j; k<old->dacl->num_aces-1;k++) {
 444                             old->dacl->aces[k] = old->dacl->aces[k+1];
 445                         }
 446                         old->dacl->num_aces--;
 447                         found = True;
 448                         break;
 449                     }
 450                 }
 451
 452                 if (!found) {
 453                 printf("ACL for ACE:");
 454                 print_ace(stdout, &sd->dacl->aces[i]);
 455                 printf(" not found\n");
 456                 }
 457             }
 458             break;
 459         case SMB_ACL_MODIFY:
 460             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 461                 bool found = False;
 462
 463                 for (j=0;old->dacl && j<old->dacl->num_aces;j++) {
 464                     if (dom_sid_equal(&sd->dacl->aces[i].trustee,
 465                         &old->dacl->aces[j].trustee)) {
 466                         old->dacl->aces[j] = sd->dacl->aces[i];
 467                         found = True;
 468                     }
 469                 }
 470
 471                 if (!found) {
 472                     printf("ACL for SID %s not found\n",
 473                            sid_string_tos(&sd->dacl->aces[i].trustee));
 474                 }
 475             }
 476
 477             if (sd->owner_sid) {
 478                 old->owner_sid = sd->owner_sid;
 479             }
 480
 481             if (sd->group_sid) {
 482                 old->group_sid = sd->group_sid;
 483             }
 484             break;
 485         case SMB_ACL_ADD:
 486             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 487                 add_ace(mem_ctx, &old->dacl, &sd->dacl->aces[i]);
 488             }
 489             break;
 490         case SMB_ACL_SET:
 491             old = sd;
 492             break;
 493         case SMB_SD_DELETE:
 494             if (!delete_share_security(sharename)) {
 495                 fprintf( stderr, "Failed to delete security descriptor for "
 496                          "share [%s]\n", sharename );
 497                 return -1;
 498             }
 499             return 0;
 500         }
 501
 502         /* Denied ACE entries must come before allowed ones */
 503         sort_acl(old->dacl);
 504
 505         if ( !set_share_security( sharename, old ) ) {
 506             fprintf( stderr, "Failed to store acl for share [%s]\n", sharename );
 507             return 2;
 508         }
 509         return 0;
 510 }
 511
 512 /********************************************************************
 513   main program
 514 ********************************************************************/
 515
 516 int main(int argc, const char *argv[])
 517 {
 518         int opt;
 519         int retval = 0;
 520         enum acl_mode mode = SMB_ACL_SET;
 521         static char *the_acl = NULL;
 522         fstring sharename;
 523         bool force_acl = False;
 524         int snum;
 525         poptContext pc;
 526         bool initialize_sid = False;
 527         struct poptOption long_options[] = {
 528                 POPT_AUTOHELP
 529                 { "remove", 'r', POPT_ARG_STRING, &the_acl, 'r', "Remove ACEs", "ACL" },
 530                 { "modify", 'm', POPT_ARG_STRING, &the_acl, 'm', "Modify existing ACEs", "ACL" },
 531                 { "add", 'a', POPT_ARG_STRING, &the_acl, 'a', "Add ACEs", "ACL" },
 532                 { "replace", 'R', POPT_ARG_STRING, &the_acl, 'R', "Overwrite share permission ACL", "ACLS" },
 533                 { "delete", 'D', POPT_ARG_NONE, NULL, 'D', "Delete the entire security descriptor" },
 534                 { "view", 'v', POPT_ARG_NONE, NULL, 'v', "View current share permissions" },
 535                 { "machine-sid", 'M', POPT_ARG_NONE, NULL, 'M', "Initialize the machine SID" },
 536                 { "force", 'F', POPT_ARG_NONE, NULL, 'F', "Force storing the ACL", "ACLS" },
 537                 POPT_COMMON_SAMBA
 538                 { NULL }
 539         };
 540
 541         if ( !(ctx = talloc_stackframe()) ) {
 542                 fprintf( stderr, "Failed to initialize talloc context!\n");
 543                 return -1;
 544         }
 545
 546         /* set default debug level to 1 regardless of what smb.conf sets */
 547         setup_logging( "sharesec", DEBUG_STDERR);
 548
 549         load_case_tables();
 550
 551         lp_set_cmdline("log level", "1");
 552
 553         pc = poptGetContext("sharesec", argc, argv, long_options, 0);
 554
 555         poptSetOtherOptionHelp(pc, "sharename\n");
 556
 557         while ((opt = poptGetNextOpt(pc)) != -1) {
 558                 switch (opt) {
 559                 case 'r':
 560                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 561                         mode = SMB_ACL_DELETE;
 562                         break;
 563
 564                 case 'm':
 565                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 566                         mode = SMB_ACL_MODIFY;
 567                         break;
 568
 569                 case 'a':
 570                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 571                         mode = SMB_ACL_ADD;
 572                         break;
 573
 574                 case 'R':
 575                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 576                         mode = SMB_ACL_SET;
 577                         break;
 578
 579                 case 'D':
 580                         mode = SMB_SD_DELETE;
 581                         break;
 582
 583                 case 'v':
 584                         mode = SMB_ACL_VIEW;
 585                         break;
 586
 587                 case 'F':
 588                         force_acl = True;
 589                         break;
 590
 591                 case 'M':
 592                         initialize_sid = True;
 593                         break;
 594                 }
 595         }
 596
 597         setlinebuf(stdout);
 598
 599         lp_load_with_registry_shares( get_dyn_CONFIGFILE(), False, False, False,
 600                                       True );
 601
 602         /* check for initializing secrets.tdb first */
 603
 604         if ( initialize_sid ) {
 605                 struct dom_sid *sid = get_global_sam_sid();
 606
 607                 if ( !sid ) {
 608                         fprintf( stderr, "Failed to retrieve Machine SID!\n");
 609                         return 3;
 610                 }
 611
 612                 printf ("%s\n", sid_string_tos( sid ) );
 613                 return 0;
 614         }
 615
 616         if ( mode == SMB_ACL_VIEW && force_acl ) {
 617                 fprintf( stderr, "Invalid combination of -F and -v\n");
 618                 return -1;
 619         }
 620
 621         /* get the sharename */
 622
 623         if(!poptPeekArg(pc)) {
 624                 poptPrintUsage(pc, stderr, 0);
 625                 return -1;
 626         }
 627
 628         fstrcpy(sharename, poptGetArg(pc));
 629
 630         snum = lp_servicenumber( sharename );
 631
 632         if ( snum == -1 && !force_acl ) {
 633                 fprintf( stderr, "Invalid sharename: %s\n", sharename);
 634                 return -1;
 635         }
 636
 637         retval = change_share_sec(ctx, sharename, the_acl, mode);
 638
 639         talloc_destroy(ctx);
 640
 641         return retval;
 642 }