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