summaryrefslogtreecommitdiff
path: root/source3/utils/profiles.c
blob: afaa83f63846e86e8a8e8b236878814eb7b95ad4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
/* 
   Samba Unix/Linux SMB client utility profiles.c 
   Copyright (C) 2002 Richard Sharpe, rsharpe@richardsharpe.com
   Copyright (C) 2003 Jelmer Vernooij (conversion to popt)

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
 
/*************************************************************************
                                                       
 A utility to report and change SIDs in registry files 
                                     
 Many of the ideas in here come from other people and software. 
 I first looked in Wine in misc/registry.c and was also influenced by
 http://www.wednesday.demon.co.uk/dosreg.html

 Which seems to contain comments from someone else. I reproduce them here
 incase the site above disappears. It actually comes from 
 http://home.eunet.no/~pnordahl/ntpasswd/WinReg.txt. 

The windows NT registry has 2 different blocks, where one can occure many
times...

the "regf"-Block
================
 
"regf" is obviously the abbreviation for "Registry file". "regf" is the
signature of the header-block which is always 4kb in size, although only
the first 64 bytes seem to be used and a checksum is calculated over
the first 0x200 bytes only!

Offset            Size      Contents
0x00000000      D-Word      ID: ASCII-"regf" = 0x66676572
0x00000004      D-Word      ???? //see struct REGF
0x00000008      D-Word      ???? Always the same value as at 0x00000004
0x0000000C      Q-Word      last modify date in WinNT date-format
0x00000014      D-Word      1
0x00000018      D-Word      3
0x0000001C      D-Word      0
0x00000020      D-Word      1
0x00000024      D-Word      Offset of 1st key record
0x00000028      D-Word      Size of the data-blocks (Filesize-4kb)
0x0000002C      D-Word      1
0x000001FC      D-Word      Sum of all D-Words from 0x00000000 to
0x000001FB  //XOR of all words. Nigel

I have analyzed more registry files (from multiple machines running
NT 4.0 german version) and could not find an explanation for the values
marked with ???? the rest of the first 4kb page is not important...

the "hbin"-Block
================
I don't know what "hbin" stands for, but this block is always a multiple
of 4kb in size.

Inside these hbin-blocks the different records are placed. The memory-
management looks like a C-compiler heap management to me...

hbin-Header
===========
Offset      Size      Contents
0x0000      D-Word      ID: ASCII-"hbin" = 0x6E696268
0x0004      D-Word      Offset from the 1st hbin-Block
0x0008      D-Word      Offset to the next hbin-Block
0x001C      D-Word      Block-size

The values in 0x0008 and 0x001C should be the same, so I don't know
if they are correct or swapped...

From offset 0x0020 inside a hbin-block data is stored with the following
format:

Offset      Size      Contents
0x0000      D-Word      Data-block size    //this size must be a
multiple of 8. Nigel
0x0004      ????      Data
 
If the size field is negative (bit 31 set), the corresponding block
is free and has a size of -blocksize!

The data is stored as one record per block. Block size is a multiple
of 4 and the last block reaches the next hbin-block, leaving no room.

Records in the hbin-blocks
==========================

nk-Record

      The nk-record can be treated as a kombination of tree-record and
      key-record of the win 95 registry.

lf-Record

      The lf-record is the counterpart to the RGKN-record (the
      hash-function)

vk-Record

      The vk-record consists information to a single value.

sk-Record

      sk (? Security Key ?) is the ACL of the registry.

Value-Lists

      The value-lists contain information about which values are inside a
      sub-key and don't have a header.

Datas

      The datas of the registry are (like the value-list) stored without a
      header.

All offset-values are relative to the first hbin-block and point to the
block-size field of the record-entry. to get the file offset, you have to add
the header size (4kb) and the size field (4 bytes)...

the nk-Record
=============
Offset      Size      Contents
0x0000      Word      ID: ASCII-"nk" = 0x6B6E
0x0002      Word      for the root-key: 0x2C, otherwise 0x20  //key symbolic links 0x10. Nigel
0x0004      Q-Word      write-date/time in windows nt notation
0x0010      D-Word      Offset of Owner/Parent key
0x0014      D-Word      number of sub-Keys
0x001C      D-Word      Offset of the sub-key lf-Records
0x0024      D-Word      number of values
0x0028      D-Word      Offset of the Value-List
0x002C      D-Word      Offset of the sk-Record

0x0030      D-Word      Offset of the Class-Name //see NK structure for the use of these fields. Nigel
0x0044      D-Word      Unused (data-trash)  //some kind of run time index. Does not appear to be important. Nigel
0x0048      Word      name-length
0x004A      Word      class-name length
0x004C      ????      key-name

the Value-List
==============
Offset      Size      Contents
0x0000      D-Word      Offset 1st Value
0x0004      D-Word      Offset 2nd Value
0x????      D-Word      Offset nth Value

To determine the number of values, you have to look at the owner-nk-record!

Der vk-Record
=============
Offset      Size      Contents
0x0000      Word      ID: ASCII-"vk" = 0x6B76
0x0002      Word      name length
0x0004      D-Word      length of the data   //if top bit is set when offset contains data. Nigel
0x0008      D-Word      Offset of Data
0x000C      D-Word      Type of value
0x0010      Word      Flag
0x0012      Word      Unused (data-trash)
0x0014      ????      Name

If bit 0 of the flag-word is set, a name is present, otherwise the value has no name (=default)

If the data-size is lower 5, the data-offset value is used to store the data itself!

The data-types
==============
Wert      Beteutung
0x0001      RegSZ:             character string (in UNICODE!)
0x0002      ExpandSZ:   string with "%var%" expanding (UNICODE!)
0x0003      RegBin:           raw-binary value
0x0004      RegDWord:   Dword
0x0007      RegMultiSZ:      multiple strings, separated with 0
                  (UNICODE!)

The "lf"-record
===============
Offset      Size      Contents
0x0000      Word      ID: ASCII-"lf" = 0x666C
0x0002      Word      number of keys
0x0004      ????      Hash-Records

Hash-Record
===========
Offset      Size      Contents
0x0000      D-Word      Offset of corresponding "nk"-Record
0x0004      D-Word      ASCII: the first 4 characters of the key-name, padded with 0's. Case sensitiv!

Keep in mind, that the value at 0x0004 is used for checking the data-consistency! If you change the 
key-name you have to change the hash-value too!

//These hashrecords must be sorted low to high within the lf record. Nigel.

The "sk"-block
==============
(due to the complexity of the SAM-info, not clear jet)

Offset      Size      Contents
0x0000      Word      ID: ASCII-"sk" = 0x6B73
0x0002      Word      Unused
0x0004      D-Word      Offset of previous "sk"-Record
0x0008      D-Word      Offset of next "sk"-Record
0x000C      D-Word      usage-counter
0x0010      D-Word      Size of "sk"-record in bytes
????                                             //standard self
relative security desciptor. Nigel
????  ????      Security and auditing settings...
????

The usage counter counts the number of references to this
"sk"-record. You can use one "sk"-record for the entire registry!

Windows nt date/time format
===========================
The time-format is a 64-bit integer which is incremented every
0,0000001 seconds by 1 (I don't know how accurate it realy is!)
It starts with 0 at the 1st of january 1601 0:00! All values are
stored in GMT time! The time-zone is important to get the real
time!

Common values for win95 and win-nt
==================================
Offset values marking an "end of list", are either 0 or -1 (0xFFFFFFFF).
If a value has no name (length=0, flag(bit 0)=0), it is treated as the
"Default" entry...
If a value has no data (length=0), it is displayed as empty.

simplyfied win-3.?? registry:
=============================

+-----------+
| next rec. |---+                      +----->+------------+
| first sub |   |                      |      | Usage cnt. |
| name      |   |  +-->+------------+  |      | length     |
| value     |   |  |   | next rec.  |  |      | text       |------->+-------+
+-----------+   |  |   | name rec.  |--+      +------------+        | xxxxx |
   +------------+  |   | value rec. |-------->+------------+        +-------+
   v               |   +------------+         | Usage cnt. |
+-----------+      |                          | length     |
| next rec. |      |                          | text       |------->+-------+
| first sub |------+                          +------------+        | xxxxx |
| name      |                                                       +-------+
| value     |
+-----------+    

Greatly simplyfied structure of the nt-registry:
================================================
   
+---------------------------------------------------------------+
|                                                               |
v                                                               |
+---------+     +---------->+-----------+  +----->+---------+   |
| "nk"    |     |           | lf-rec.   |  |      | nk-rec. |   |
| ID      |     |           | # of keys |  |      | parent  |---+
| Date    |     |           | 1st key   |--+      | ....    |
| parent  |     |           +-----------+         +---------+
| suk-keys|-----+
| values  |--------------------->+----------+
| SK-rec. |---------------+      | 1. value |--> +----------+
| class   |--+            |      +----------+    | vk-rec.  |
+---------+  |            |                      | ....     |
             v            |                      | data     |--> +-------+
      +------------+      |                      +----------+    | xxxxx |
      | Class name |      |                                      +-------+
      +------------+      |
                          v
          +---------+    +---------+
   +----->| next sk |--->| Next sk |--+
   |  +---| prev sk |<---| prev sk |  |
   |  |   | ....    |    | ...     |  |
   |  |   +---------+    +---------+  |
   |  |         ^          |          |
      |         +----------+          |
      +-------------------------------+

---------------------------------------------------------------------------

Hope this helps....  (Although it was "fun" for me to uncover this things,
                  it took me several sleepless nights ;)

            B.D.

*************************************************************************/
#include "includes.h"
#include <stdio.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <sys/mman.h>

typedef unsigned int DWORD;
typedef unsigned short WORD;

#define REG_REGF_ID 0x66676572

typedef struct regf_block {
  DWORD REGF_ID;     /* regf */
  DWORD uk1;
  DWORD uk2;
  DWORD tim1, tim2;
  DWORD uk3;             /* 1 */
  DWORD uk4;             /* 3 */
  DWORD uk5;             /* 0 */
  DWORD uk6;             /* 1 */
  DWORD first_key;       /* offset */
  unsigned int dblk_size;
  DWORD uk7[116];        /* 1 */
  DWORD chksum;
} REGF_HDR;

typedef struct hbin_sub_struct {
  DWORD dblocksize;
  char data[1];
} HBIN_SUB_HDR;

#define REG_HBIN_ID 0x6E696268

typedef struct hbin_struct {
  DWORD HBIN_ID; /* hbin */
  DWORD next_off;
  DWORD prev_off;
  DWORD uk1;
  DWORD uk2;
  DWORD uk3;
  DWORD uk4;
  DWORD blk_size;
  HBIN_SUB_HDR hbin_sub_hdr;
} HBIN_HDR;

#define REG_NK_ID 0x6B6E

typedef struct nk_struct {
  WORD NK_ID;
  WORD type;
  DWORD t1, t2;
  DWORD uk1;
  DWORD own_off;
  DWORD subk_num;
  DWORD uk2;
  DWORD lf_off;
  DWORD uk3;
  DWORD val_cnt;
  DWORD val_off;
  DWORD sk_off;
  DWORD clsnam_off;
} NK_HDR;

#define REG_SK_ID 0x6B73

typedef struct sk_struct {
  WORD SK_ID;
  WORD uk1;
  DWORD prev_off;
  DWORD next_off;
  DWORD ref_cnt;
  DWORD rec_size;
  char sec_desc[1];
} SK_HDR;

typedef struct sec_desc_rec {
  WORD rev;
  WORD type;
  DWORD owner_off;
  DWORD group_off;
  DWORD sacl_off;
  DWORD dacl_off;
} MY_SEC_DESC;

typedef struct ace_struct {
    unsigned char type;
    unsigned char flags;
    unsigned short length;
    unsigned int perms;
    DOM_SID trustee;
} ACE;

typedef struct acl_struct {
  WORD rev;
  WORD size;
  DWORD num_aces;
  ACE *aces;   /* One or more ACEs */
} ACL;

#define OFF(f) (0x1000 + (f) + 4) 

static void print_sid(DOM_SID *sid);

int verbose = 1;
DOM_SID old_sid, new_sid;
int change = 0, new = 0;

/* Compare two SIDs for equality */
static int my_sid_equal(DOM_SID *s1, DOM_SID *s2)
{
  int sa1, sa2;

  if (s1->sid_rev_num != s2->sid_rev_num) return 0;

  sa1 = s1->num_auths; sa2 = s2->num_auths;

  if (sa1 != sa2) return 0;

  return !memcmp((char *)&s1->id_auth, (char *)&s2->id_auth,
		6 + sa1 * 4);

}

/*
 * Quick and dirty to read a SID in S-1-5-21-x-y-z-rid format and 
 * construct a DOM_SID
 */
static int get_sid(DOM_SID *sid, const unsigned char *sid_str)
{
  int i = 0, auth;
  const unsigned char *lstr; 

  if (strncmp(sid_str, "S-1-5", 5)) {
    fprintf(stderr, "Does not conform to S-1-5...: %s\n", sid_str);
    return 0;
  }

  /* We only allow strings of form S-1-5... */

  sid->sid_rev_num = 1;
  sid->id_auth[5] = 5;

  lstr = sid_str + 5;

  while (1) {
    if (!lstr || !lstr[0] || sscanf(lstr, "-%u", &auth) == 0) {
      if (i < 4) {
	fprintf(stderr, "Not of form -d-d...: %s, %u\n", lstr, i);
	return 0;
      }
      sid->num_auths=i;
      print_sid(sid);
      return 1;
    }

    SIVAL(&sid->sub_auths[i], 0, auth);
    i++;
    lstr = strchr(lstr + 1, '-'); 
  }

  return 1;
}

/* 
 * Replace SID1, component by component with SID2
 * Assumes will never be called with unequal length SIDS
 * so only touches 21-x-y-z-rid portion
 * This routine does not need to deal with endianism as 
 * long as the incoming SIDs are both in the same (LE) format.
 */
static void change_sid(DOM_SID *s1, DOM_SID *s2)
{
  int i;
  
  for (i=0; i<s1->num_auths; i++) {
    s1->sub_auths[i] = s2->sub_auths[i];
  }
}

static void print_sid(DOM_SID *sid)
{
  int i, comps = sid->num_auths;
  fprintf(stdout, "S-%u-%u", sid->sid_rev_num, sid->id_auth[5]);

  for (i = 0; i < comps; i++) {

    fprintf(stdout, "-%u", IVAL(&sid->sub_auths[i],0));

  }
  fprintf(stdout, "\n");
}

static void process_sid(DOM_SID *sid, DOM_SID *o_sid, DOM_SID *n_sid) 
{
  int i;
  if (my_sid_equal(sid, o_sid)) {

    for (i=0; i<sid->num_auths; i++) {
      sid->sub_auths[i] = n_sid->sub_auths[i];

    }

  }

}

static void process_acl(ACL *acl, const char *prefix)
{
  int ace_cnt, i;
  ACE *ace;

  ace_cnt = IVAL(&acl->num_aces, 0);
  ace = (ACE *)&acl->aces;
  if (verbose) fprintf(stdout, "%sACEs: %u\n", prefix, ace_cnt);
  for (i=0; i<ace_cnt; i++) {
    if (verbose) fprintf(stdout, "%s  Perms: %08X, SID: ", prefix,
			 IVAL(&ace->perms, 0));
    if (change)
      process_sid(&ace->trustee, &old_sid, &new_sid);
    print_sid(&ace->trustee);
    ace = (ACE *)((char *)ace + SVAL(&ace->length, 0));
  }
} 

int main(int argc, char *argv[])
{
  int opt;
  int fd, start = 0;
  char *base;
  struct stat sbuf;
  REGF_HDR *regf_hdr;
  HBIN_HDR *hbin_hdr;
  NK_HDR *nk_hdr;
  SK_HDR *sk_hdr;
  DWORD first_sk_off, sk_off;
  MY_SEC_DESC *sec_desc;
  int *ptr;
  struct poptOption long_options[] = {
	  POPT_AUTOHELP
	  { "verbose", 'v', POPT_ARG_NONE, NULL, 'v', "Sets verbose mode" },
	  { "change-sid", 'c', POPT_ARG_STRING, NULL, 'c', "Provides SID to change" },
	  { "new-sid", 'n', POPT_ARG_STRING, NULL, 'n', "Provides SID to change to" },
	  { 0, 0, 0, 0 }
  };

  poptContext pc;

  pc = poptGetContext("profiles", argc, (const char **)argv, long_options, 
					  POPT_CONTEXT_KEEP_FIRST);

  poptSetOtherOptionHelp(pc, "<profilefile>");

  /*
   * Now, process the arguments
   */

  while ((opt = poptGetNextOpt(pc)) != -1) {
    switch (opt) {
	case 'c':
		change = 1;
		if (!get_sid(&old_sid, poptGetOptArg(pc))) {
			fprintf(stderr, "Argument to -c should be a SID in form of S-1-5-...\n");
			poptPrintUsage(pc, stderr, 0);
			exit(254);
		}
		break;

	case 'n':
		new = 1;
		if (!get_sid(&new_sid, poptGetOptArg(pc))) {
			fprintf(stderr, "Argument to -n should be a SID in form of S-1-5-...\n");
			poptPrintUsage(pc, stderr, 0);
			exit(253);
		}

		break;

	case 'v':
		verbose++;
		break;
	}
  }

  if (!poptPeekArg(pc)) {
	  poptPrintUsage(pc, stderr, 0);
	  exit(1);
  }

  if ((!change & new) || (change & !new)) {
	  fprintf(stderr, "You must specify both -c and -n if one or the other is set!\n");
	  poptPrintUsage(pc, stderr, 0);
	  exit(252);
  }

  poptGetArg(pc); /* To get argv[0] */

  fd = open(poptPeekArg(pc), O_RDWR, 0000);

  if (fd < 0) {
    fprintf(stderr, "Could not open %s: %s\n", poptPeekArg(pc), 
	strerror(errno));
    exit(2);
  }

  if (fstat(fd, &sbuf) < 0) {
    fprintf(stderr, "Could not stat file %s, %s\n", poptPeekArg(pc),
	strerror(errno));
    exit(3);
  }

  /*
   * Now, mmap the file into memory, check the header and start
   * dealing with the records. We are interested in the sk record
   */
  start = 0;
  base = mmap(&start, sbuf.st_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);

  if ((int)base == -1) {
    fprintf(stderr, "Could not mmap file: %s, %s\n", poptPeekArg(pc),
	strerror(errno));
    exit(4);
  }

  /*
   * In what follows, and in places above, in order to work on both LE and
   * BE platforms, we have to use the Samba macros to extract SHORT, LONG
   * and associated UNSIGNED quantities from the data in the mmap'd file.
   * NOTE, however, that we do not need to do anything with memory
   * addresses that we construct from pointers in our address space.
   * For example, 
   *
   *    sec_desc = (MY_SEC_DESC *)&(sk_hdr->sec_desc[0]);
   *
   * is simply taking the address of a structure we already have the address
   * of in our address space, while, the fields within it, will have to 
   * be accessed with the macros:
   *
   * owner_sid = (DOM_SID *)(&sk_hdr->sec_desc[0] + 
   *                         IVAL(&sec_desc->owner_off, 0));
   *
   * Which is pulling out an offset and adding it to an existing pointer.
   *
   */

  regf_hdr = (REGF_HDR *)base;

  if (verbose) fprintf(stdout, "Registry file size: %u\n", (unsigned int)sbuf.st_size);

  if (IVAL(&regf_hdr->REGF_ID, 0) != REG_REGF_ID) {
    fprintf(stderr, "Incorrect Registry file (doesn't have header ID): %s\n", poptPeekArg(pc));
    exit(5);
  }

  if (verbose) fprintf(stdout, "First Key Off: %u, Data Block Size: %u\n",
		       IVAL(&regf_hdr->first_key, 0), 
		       IVAL(&regf_hdr->dblk_size, 0));

  hbin_hdr = (HBIN_HDR *)(base + 0x1000); /* No need for Endian stuff */

  /*
   * This should be the hbin_hdr 
   */

  if (IVAL(&hbin_hdr->HBIN_ID, 0) != REG_HBIN_ID) {
    fprintf(stderr, "Incorrect hbin hdr: %s\n", poptPeekArg(pc));
    exit(6);
  } 

  if (verbose) fprintf(stdout, "Next Off: %u, Prev Off: %u\n", 
		       IVAL(&hbin_hdr->next_off, 0), 
		       IVAL(&hbin_hdr->prev_off, 0));

  nk_hdr = (NK_HDR *)(base + 0x1000 + IVAL(&regf_hdr->first_key, 0) + 4);

  if (SVAL(&nk_hdr->NK_ID, 0) != REG_NK_ID) {
    fprintf(stderr, "Incorrect NK Header: %s\n", poptPeekArg(pc));
    exit(7);
  }

  sk_off = first_sk_off = IVAL(&nk_hdr->sk_off, 0);
  if (verbose) {
    fprintf(stdout, "Type: %0x\n", SVAL(&nk_hdr->type, 0));
    fprintf(stdout, "SK Off    : %o\n", (0x1000 + sk_off + 4));  
  }

  sk_hdr = (SK_HDR *)(base + 0x1000 + sk_off + 4);

  do {
    DOM_SID *owner_sid, *group_sid;
    ACL *sacl, *dacl;
    if (SVAL(&sk_hdr->SK_ID, 0) != REG_SK_ID) {
      fprintf(stderr, "Incorrect SK Header format: %08X\n", 
	      (0x1000 + sk_off + 4));
      exit(8);
    }
    ptr = (int *)sk_hdr;
    if (verbose) fprintf(stdout, "Off: %08X, Refs: %u, Size: %u\n",
			 sk_off, IVAL(&sk_hdr->ref_cnt, 0), 
			 IVAL(&sk_hdr->rec_size, 0));

    sec_desc = (MY_SEC_DESC *)&(sk_hdr->sec_desc[0]);
    owner_sid = (DOM_SID *)(&sk_hdr->sec_desc[0] +
			    IVAL(&sec_desc->owner_off, 0));
    group_sid = (DOM_SID *)(&sk_hdr->sec_desc[0] + 
			    IVAL(&sec_desc->group_off, 0));
    sacl = (ACL *)(&sk_hdr->sec_desc[0] + 
		   IVAL(&sec_desc->sacl_off, 0));
    dacl = (ACL *)(&sk_hdr->sec_desc[0] + 
		   IVAL(&sec_desc->dacl_off, 0));
    if (verbose)fprintf(stdout, "  Owner SID: "); 
    if (change) process_sid(owner_sid, &old_sid, &new_sid);
    if (verbose) print_sid(owner_sid);
    if (verbose) fprintf(stdout, "  Group SID: "); 
    if (change) process_sid(group_sid, &old_sid, &new_sid);
    if (verbose) print_sid(group_sid);
    fprintf(stdout, "  SACL: ");
    if (!sec_desc->sacl_off) { /* LE zero == BE zero */
      if (verbose) fprintf(stdout, "NONE\n");
    }
    else 
      process_acl(sacl, "    ");
    if (verbose) fprintf(stdout, "  DACL: ");
    if (!sec_desc->dacl_off) {
      if (verbose) fprintf(stdout, "NONE\n");
    }
    else 
      process_acl(dacl, "    ");
    sk_off = IVAL(&sk_hdr->prev_off, 0);
    sk_hdr = (SK_HDR *)(base + OFF(IVAL(&sk_hdr->prev_off, 0)));
  } while (sk_off != first_sk_off);

  munmap(base, sbuf.st_size); 

  poptFreeContext(pc);

  close(fd);
  return 0;
}