source/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 2 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, write to the Free Software
  22  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23  */
  24
  25
  26 #include "includes.h"
  27
  28 static TALLOC_CTX *ctx;
  29
  30 enum acl_mode {SMB_ACL_DELETE, SMB_ACL_MODIFY, SMB_ACL_ADD, SMB_ACL_SET, SMB_ACL_VIEW };
  31
  32 struct perm_value {
  33         const char *perm;
  34         uint32 mask;
  35 };
  36
  37 /* These values discovered by inspection */
  38
  39 static const struct perm_value special_values[] = {
  40         { "R", SEC_RIGHTS_FILE_READ },
  41         { "W", SEC_RIGHTS_FILE_WRITE },
  42         { "X", SEC_RIGHTS_FILE_EXECUTE },
  43         { "D", SEC_STD_DELETE },
  44         { "P", SEC_STD_WRITE_DAC },
  45         { "O", SEC_STD_WRITE_OWNER },
  46         { NULL, 0 },
  47 };
  48
  49 #define SEC_RIGHTS_DIR_CHANGE ( SEC_RIGHTS_DIR_READ|SEC_STD_DELETE|SEC_RIGHTS_DIR_WRITE|SEC_DIR_TRAVERSE )
  50
  51 static const struct perm_value standard_values[] = {
  52         { "READ",   SEC_RIGHTS_DIR_READ|SEC_DIR_TRAVERSE },
  53         { "CHANGE", SEC_RIGHTS_DIR_CHANGE },
  54         { "FULL",   SEC_RIGHTS_DIR_ALL },
  55         { NULL, 0 },
  56 };
  57
  58 /********************************************************************
  59  print an ACE on a FILE
  60 ********************************************************************/
  61
  62 static void print_ace(FILE *f, SEC_ACE *ace)
  63 {
  64         const struct perm_value *v;
  65         int do_print = 0;
  66         uint32 got_mask;
  67
  68         fprintf(f, "%s:", sid_string_static(&ace->trustee));
  69
  70         /* Ace type */
  71
  72         if (ace->type == SEC_ACE_TYPE_ACCESS_ALLOWED) {
  73                 fprintf(f, "ALLOWED");
  74         } else if (ace->type == SEC_ACE_TYPE_ACCESS_DENIED) {
  75                 fprintf(f, "DENIED");
  76         } else {
  77                 fprintf(f, "%d", ace->type);
  78         }
  79
  80         /* Not sure what flags can be set in a file ACL */
  81
  82         fprintf(f, "/%d/", ace->flags);
  83
  84         /* Standard permissions */
  85
  86         for (v = standard_values; v->perm; v++) {
  87                 if (ace->access_mask == v->mask) {
  88                         fprintf(f, "%s", v->perm);
  89                         return;
  90                 }
  91         }
  92
  93         /* Special permissions.  Print out a hex value if we have
  94            leftover bits in the mask. */
  95
  96         got_mask = ace->access_mask;
  97
  98  again:
  99         for (v = special_values; v->perm; v++) {
 100                 if ((ace->access_mask & v->mask) == v->mask) {
 101                         if (do_print) {
 102                                 fprintf(f, "%s", v->perm);
 103                         }
 104                         got_mask &= ~v->mask;
 105                 }
 106         }
 107
 108         if (!do_print) {
 109                 if (got_mask != 0) {
 110                         fprintf(f, "0x%08x", ace->access_mask);
 111                 } else {
 112                         do_print = 1;
 113                         goto again;
 114                 }
 115         }
 116 }
 117
 118 /********************************************************************
 119  print a ascii version of a security descriptor on a FILE handle
 120 ********************************************************************/
 121
 122 static void sec_desc_print(FILE *f, SEC_DESC *sd)
 123 {
 124         uint32 i;
 125
 126         fprintf(f, "REVISION:%d\n", sd->revision);
 127
 128         /* Print owner and group sid */
 129
 130         fprintf(f, "OWNER:%s\n", sid_string_static(sd->owner_sid));
 131
 132         fprintf(f, "GROUP:%s\n", sid_string_static(sd->group_sid));
 133
 134         /* Print aces */
 135         for (i = 0; sd->dacl && i < sd->dacl->num_aces; i++) {
 136                 SEC_ACE *ace = &sd->dacl->aces[i];
 137                 fprintf(f, "ACL:");
 138                 print_ace(f, ace);
 139                 fprintf(f, "\n");
 140         }
 141
 142 }
 143
 144 /********************************************************************
 145     parse an ACE in the same format as print_ace()
 146 ********************************************************************/
 147
 148 static BOOL parse_ace(SEC_ACE *ace, const char *orig_str)
 149 {
 150         char *p;
 151         const char *cp;
 152         fstring tok;
 153         unsigned int atype = 0;
 154         unsigned int aflags = 0;
 155         unsigned int amask = 0;
 156         DOM_SID sid;
 157         SEC_ACCESS mask;
 158         const struct perm_value *v;
 159         char *str = SMB_STRDUP(orig_str);
 160
 161         if (!str) {
 162                 return False;
 163         }
 164
 165         ZERO_STRUCTP(ace);
 166         p = strchr_m(str,':');
 167         if (!p) {
 168                 printf("ACE '%s': missing ':'.\n", orig_str);
 169                 SAFE_FREE(str);
 170                 return False;
 171         }
 172         *p = '\0';
 173         p++;
 174         /* Try to parse numeric form */
 175
 176         if (sscanf(p, "%i/%i/%i", &atype, &aflags, &amask) == 3 &&
 177             string_to_sid(&sid, str)) {
 178                 goto done;
 179         }
 180
 181         /* Try to parse text form */
 182
 183         if (!string_to_sid(&sid, str)) {
 184                 printf("ACE '%s': failed to convert '%s' to SID\n",
 185                         orig_str, str);
 186                 SAFE_FREE(str);
 187                 return False;
 188         }
 189
 190         cp = p;
 191         if (!next_token(&cp, tok, "/", sizeof(fstring))) {
 192                 printf("ACE '%s': failed to find '/' character.\n",
 193                         orig_str);
 194                 SAFE_FREE(str);
 195                 return False;
 196         }
 197
 198         if (strncmp(tok, "ALLOWED", strlen("ALLOWED")) == 0) {
 199                 atype = SEC_ACE_TYPE_ACCESS_ALLOWED;
 200         } else if (strncmp(tok, "DENIED", strlen("DENIED")) == 0) {
 201                 atype = SEC_ACE_TYPE_ACCESS_DENIED;
 202         } else {
 203                 printf("ACE '%s': missing 'ALLOWED' or 'DENIED' entry at '%s'\n",
 204                         orig_str, tok);
 205                 SAFE_FREE(str);
 206                 return False;
 207         }
 208
 209         /* Only numeric form accepted for flags at present */
 210         /* no flags on share permissions */
 211
 212         if (!(next_token(&cp, tok, "/", sizeof(fstring)) &&
 213               sscanf(tok, "%i", &aflags) && aflags == 0)) {
 214                 printf("ACE '%s': bad integer flags entry at '%s'\n",
 215                         orig_str, tok);
 216                 SAFE_FREE(str);
 217                 return False;
 218         }
 219
 220         if (!next_token(&cp, tok, "/", sizeof(fstring))) {
 221                 printf("ACE '%s': missing / at '%s'\n",
 222                         orig_str, tok);
 223                 SAFE_FREE(str);
 224                 return False;
 225         }
 226
 227         if (strncmp(tok, "0x", 2) == 0) {
 228                 if (sscanf(tok, "%i", &amask) != 1) {
 229                         printf("ACE '%s': bad hex number at '%s'\n",
 230                                 orig_str, tok);
 231                         SAFE_FREE(str);
 232                         return False;
 233                 }
 234                 goto done;
 235         }
 236
 237         for (v = standard_values; v->perm; v++) {
 238                 if (strcmp(tok, v->perm) == 0) {
 239                         amask = v->mask;
 240                         goto done;
 241                 }
 242         }
 243
 244         p = tok;
 245
 246         while(*p) {
 247                 BOOL found = False;
 248
 249                 for (v = special_values; v->perm; v++) {
 250                         if (v->perm[0] == *p) {
 251                                 amask |= v->mask;
 252                                 found = True;
 253                         }
 254                 }
 255
 256                 if (!found) {
 257                         printf("ACE '%s': bad permission value at '%s'\n",
 258                                 orig_str, p);
 259                         SAFE_FREE(str);
 260                         return False;
 261                 }
 262                 p++;
 263         }
 264
 265         if (*p) {
 266                 SAFE_FREE(str);
 267                 return False;
 268         }
 269
 270  done:
 271         mask = amask;
 272         init_sec_ace(ace, &sid, atype, mask, aflags);
 273         SAFE_FREE(str);
 274         return True;
 275 }
 276
 277
 278 /********************************************************************
 279 ********************************************************************/
 280
 281 static SEC_DESC* parse_acl_string(TALLOC_CTX *mem_ctx, const char *szACL, size_t *sd_size )
 282 {
 283         SEC_DESC *sd = NULL;
 284         SEC_ACE *ace;
 285         SEC_ACL *acl;
 286         int num_ace;
 287         const char *pacl;
 288         int i;
 289
 290         if ( !szACL )
 291                 return NULL;
 292
 293         pacl = szACL;
 294         num_ace = count_chars( pacl, ',' ) + 1;
 295
 296         if ( !(ace = TALLOC_ZERO_ARRAY( mem_ctx, SEC_ACE, num_ace )) )
 297                 return NULL;
 298
 299         for ( i=0; i<num_ace; i++ ) {
 300                 char *end_acl = strchr_m( pacl, ',' );
 301                 fstring acl_string;
 302
 303                 strncpy( acl_string, pacl, MIN( PTR_DIFF( end_acl, pacl ), sizeof(fstring)-1) );
 304                 acl_string[MIN( PTR_DIFF( end_acl, pacl ), sizeof(fstring)-1)] = '\0';
 305
 306                 if ( !parse_ace( &ace[i], acl_string ) )
 307                         return NULL;
 308
 309                 pacl = end_acl;
 310                 pacl++;
 311         }
 312
 313         if ( !(acl = make_sec_acl( mem_ctx, NT4_ACL_REVISION, num_ace, ace )) )
 314                 return NULL;
 315
 316         sd = make_sec_desc( mem_ctx, SEC_DESC_REVISION, SEC_DESC_SELF_RELATIVE,
 317                 NULL, NULL, NULL, acl, sd_size);
 318
 319         return sd;
 320 }
 321
 322 /* add an ACE to a list of ACEs in a SEC_ACL */
 323 static BOOL add_ace(TALLOC_CTX *mem_ctx, SEC_ACL **the_acl, SEC_ACE *ace)
 324 {
 325         SEC_ACL *new_ace;
 326         SEC_ACE *aces;
 327         if (! *the_acl) {
 328                 return (((*the_acl) = make_sec_acl(mem_ctx, 3, 1, ace)) != NULL);
 329         }
 330
 331         if (!(aces = SMB_CALLOC_ARRAY(SEC_ACE, 1+(*the_acl)->num_aces))) {
 332                 return False;
 333         }
 334         memcpy(aces, (*the_acl)->aces, (*the_acl)->num_aces * sizeof(SEC_ACE));
 335         memcpy(aces+(*the_acl)->num_aces, ace, sizeof(SEC_ACE));
 336         new_ace = make_sec_acl(mem_ctx,(*the_acl)->revision,1+(*the_acl)->num_aces, aces);
 337         SAFE_FREE(aces);
 338         (*the_acl) = new_ace;
 339         return True;
 340 }
 341
 342 /* The MSDN is contradictory over the ordering of ACE entries in an ACL.
 343    However NT4 gives a "The information may have been modified by a
 344    computer running Windows NT 5.0" if denied ACEs do not appear before
 345    allowed ACEs. */
 346
 347 static int ace_compare(SEC_ACE *ace1, SEC_ACE *ace2)
 348 {
 349         if (sec_ace_equal(ace1, ace2))
 350                 return 0;
 351
 352         if (ace1->type != ace2->type)
 353                 return ace2->type - ace1->type;
 354
 355         if (sid_compare(&ace1->trustee, &ace2->trustee))
 356                 return sid_compare(&ace1->trustee, &ace2->trustee);
 357
 358         if (ace1->flags != ace2->flags)
 359                 return ace1->flags - ace2->flags;
 360
 361         if (ace1->access_mask != ace2->access_mask)
 362                 return ace1->access_mask - ace2->access_mask;
 363
 364         if (ace1->size != ace2->size)
 365                 return ace1->size - ace2->size;
 366
 367         return memcmp(ace1, ace2, sizeof(SEC_ACE));
 368 }
 369
 370 static void sort_acl(SEC_ACL *the_acl)
 371 {
 372         uint32 i;
 373         if (!the_acl) return;
 374
 375         qsort(the_acl->aces, the_acl->num_aces, sizeof(the_acl->aces[0]), QSORT_CAST ace_compare);
 376
 377         for (i=1;i<the_acl->num_aces;) {
 378                 if (sec_ace_equal(&the_acl->aces[i-1], &the_acl->aces[i])) {
 379                         int j;
 380                         for (j=i; j<the_acl->num_aces-1; j++) {
 381                                 the_acl->aces[j] = the_acl->aces[j+1];
 382                         }
 383                         the_acl->num_aces--;
 384                 } else {
 385                         i++;
 386                 }
 387         }
 388 }
 389
 390
 391 static int change_share_sec(TALLOC_CTX *mem_ctx, const char *sharename, char *the_acl, enum acl_mode mode)
 392 {
 393         SEC_DESC *sd;
 394         SEC_DESC *old = NULL;
 395         size_t sd_size = 0;
 396         uint32 i, j;
 397
 398         if (mode != SMB_ACL_SET) {
 399             if (!(old = get_share_security( mem_ctx, sharename, &sd_size )) ) {
 400                 fprintf(stderr, "Unable to retrieve permissions for share [%s]\n", sharename);
 401                 return -1;
 402             }
 403         }
 404
 405         if ( (mode != SMB_ACL_VIEW) && !(sd = parse_acl_string(mem_ctx, the_acl, &sd_size )) ) {
 406                 fprintf( stderr, "Failed to parse acl\n");
 407                 return -1;
 408         }
 409
 410         switch (mode) {
 411         case SMB_ACL_VIEW:
 412                 sec_desc_print( stdout, old);
 413                 return 0;
 414         case SMB_ACL_DELETE:
 415             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 416                 BOOL found = False;
 417
 418                 for (j=0;old->dacl && j<old->dacl->num_aces;j++) {
 419                     if (sec_ace_equal(&sd->dacl->aces[i], &old->dacl->aces[j])) {
 420                         uint32 k;
 421                         for (k=j; k<old->dacl->num_aces-1;k++) {
 422                             old->dacl->aces[k] = old->dacl->aces[k+1];
 423                         }
 424                         old->dacl->num_aces--;
 425                         found = True;
 426                         break;
 427                     }
 428                 }
 429
 430                 if (!found) {
 431                 printf("ACL for ACE:");
 432                 print_ace(stdout, &sd->dacl->aces[i]);
 433                 printf(" not found\n");
 434                 }
 435             }
 436
 437             break;
 438         case SMB_ACL_MODIFY:
 439             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 440                 BOOL found = False;
 441
 442                 for (j=0;old->dacl && j<old->dacl->num_aces;j++) {
 443                     if (sid_equal(&sd->dacl->aces[i].trustee,
 444                         &old->dacl->aces[j].trustee)) {
 445                         old->dacl->aces[j] = sd->dacl->aces[i];
 446                         found = True;
 447                     }
 448                 }
 449
 450                 if (!found) {
 451                     printf("ACL for SID %s not found\n", sid_string_static(&sd->dacl->aces[i].trustee));
 452                 }
 453             }
 454
 455             if (sd->owner_sid) {
 456                 old->owner_sid = sd->owner_sid;
 457             }
 458
 459             if (sd->group_sid) {
 460                 old->group_sid = sd->group_sid;
 461             }
 462             break;
 463         case SMB_ACL_ADD:
 464             for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
 465                 add_ace(mem_ctx, &old->dacl, &sd->dacl->aces[i]);
 466             }
 467             break;
 468         case SMB_ACL_SET:
 469             old = sd;
 470             break;
 471         }
 472
 473         /* Denied ACE entries must come before allowed ones */
 474         sort_acl(old->dacl);
 475
 476         if ( !set_share_security( sharename, old ) ) {
 477             fprintf( stderr, "Failed to store acl for share [%s]\n", sharename );
 478             return 2;
 479         }
 480         return 0;
 481 }
 482
 483 /********************************************************************
 484   main program
 485 ********************************************************************/
 486
 487 int main(int argc, const char *argv[])
 488 {
 489         int opt;
 490         int retval = 0;
 491         enum acl_mode mode = SMB_ACL_SET;
 492         static char *the_acl = NULL;
 493         fstring sharename;
 494         BOOL force_acl = False;
 495         int snum;
 496         poptContext pc;
 497         BOOL initialize_sid = False;
 498         struct poptOption long_options[] = {
 499                 POPT_AUTOHELP
 500                 { "remove", 'r', POPT_ARG_STRING, &the_acl, 'r', "Delete an ACE", "ACL" },
 501                 { "modify", 'm', POPT_ARG_STRING, &the_acl, 'm', "Modify an acl", "ACL" },
 502                 { "add", 'a', POPT_ARG_STRING, &the_acl, 'a', "Add an ACE", "ACL" },
 503                 { "replace", 'R', POPT_ARG_STRING, &the_acl, 'R', "Set share mission ACL", "ACLS" },
 504                 { "view", 'v', POPT_ARG_NONE, NULL, 'v', "View current share permissions" },
 505                 { "machine-sid", 'M', POPT_ARG_NONE, NULL, 'M', "Initialize the machine SID" },
 506                 { "force", 'F', POPT_ARG_NONE, NULL, 'F', "Force storing the ACL", "ACLS" },
 507                 POPT_COMMON_SAMBA
 508                 { NULL }
 509         };
 510
 511         if ( !(ctx = talloc_init("main")) ) {
 512                 fprintf( stderr, "Failed to initialize talloc context!\n");
 513                 return -1;
 514         }
 515
 516         /* set default debug level to 1 regardless of what smb.conf sets */
 517         setup_logging( "sharesec", True );
 518         DEBUGLEVEL_CLASS[DBGC_ALL] = 1;
 519         dbf = x_stderr;
 520         x_setbuf( x_stderr, NULL );
 521
 522         pc = poptGetContext("sharesec", argc, argv, long_options, 0);
 523
 524         poptSetOtherOptionHelp(pc, "sharename\n");
 525
 526         while ((opt = poptGetNextOpt(pc)) != -1) {
 527                 switch (opt) {
 528                 case 'r':
 529                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 530                         mode = SMB_ACL_DELETE;
 531                         break;
 532
 533                 case 'm':
 534                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 535                         mode = SMB_ACL_MODIFY;
 536                         break;
 537
 538                 case 'a':
 539                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 540                         mode = SMB_ACL_ADD;
 541                         break;
 542                 case 'R':
 543                         the_acl = smb_xstrdup(poptGetOptArg(pc));
 544                         mode = SMB_ACL_SET;
 545                         break;
 546
 547                 case 'v':
 548                         mode = SMB_ACL_VIEW;
 549                         break;
 550
 551                 case 'F':
 552                         force_acl = True;
 553                         break;
 554
 555                 case 'M':
 556                         initialize_sid = True;
 557                         break;
 558                 }
 559         }
 560
 561         setlinebuf(stdout);
 562
 563         load_case_tables();
 564
 565         lp_load( dyn_CONFIGFILE, False, False, False, True );
 566
 567         /* check for initializing secrets.tdb first */
 568
 569         if ( initialize_sid ) {
 570                 DOM_SID *sid = get_global_sam_sid();
 571
 572                 if ( !sid ) {
 573                         fprintf( stderr, "Failed to retrieve Machine SID!\n");
 574                         return 3;
 575                 }
 576
 577                 printf ("%s\n", sid_string_static( sid ) );
 578                 return 0;
 579         }
 580
 581         if ( mode == SMB_ACL_VIEW && force_acl ) {
 582                 fprintf( stderr, "Invalid combination of -F and -v\n");
 583                 return -1;
 584         }
 585
 586         /* get the sharename */
 587
 588         if(!poptPeekArg(pc)) {
 589                 poptPrintUsage(pc, stderr, 0);
 590                 return -1;
 591         }
 592
 593         fstrcpy(sharename, poptGetArg(pc));
 594
 595         snum = lp_servicenumber( sharename );
 596
 597         if ( snum == -1 && !force_acl ) {
 598                 fprintf( stderr, "Invalid sharename: %s\n", sharename);
 599                 return -1;
 600         }
 601
 602         retval = change_share_sec(ctx, sharename, the_acl, mode);
 603
 604         talloc_destroy(ctx);
 605
 606         return retval;
 607 }