2 Samba Unix/Linux SMB client utility editreg.c
3 Copyright (C) 2002 Richard Sharpe, rsharpe@richardsharpe.com
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
19 /*************************************************************************
21 A utility to edit a Windows NT/2K etc registry file.
23 Many of the ideas in here come from other people and software.
24 I first looked in Wine in misc/registry.c and was also influenced by
25 http://www.wednesday.demon.co.uk/dosreg.html
27 Which seems to contain comments from someone else. I reproduce them here
28 incase the site above disappears. It actually comes from
29 http://home.eunet.no/~pnordahl/ntpasswd/WinReg.txt.
31 The goal here is to read the registry into memory, manipulate it, and then
32 write it out if it was changed by any actions of the user.
34 The windows NT registry has 2 different blocks, where one can occur many
40 "regf" is obviosly the abbreviation for "Registry file". "regf" is the
41 signature of the header-block which is always 4kb in size, although only
42 the first 64 bytes seem to be used and a checksum is calculated over
43 the first 0x200 bytes only!
46 0x00000000 D-Word ID: ASCII-"regf" = 0x66676572
47 0x00000004 D-Word ???? //see struct REGF
48 0x00000008 D-Word ???? Always the same value as at 0x00000004
49 0x0000000C Q-Word last modify date in WinNT date-format
54 0x00000024 D-Word Offset of 1st key record
55 0x00000028 D-Word Size of the data-blocks (Filesize-4kb)
57 0x000001FC D-Word Sum of all D-Words from 0x00000000 to
58 0x000001FB //XOR of all words. Nigel
60 I have analyzed more registry files (from multiple machines running
61 NT 4.0 german version) and could not find an explanation for the values
62 marked with ???? the rest of the first 4kb page is not important...
66 I don't know what "hbin" stands for, but this block is always a multiple
69 Inside these hbin-blocks the different records are placed. The memory-
70 management looks like a C-compiler heap management to me...
75 0x0000 D-Word ID: ASCII-"hbin" = 0x6E696268
76 0x0004 D-Word Offset from the 1st hbin-Block
77 0x0008 D-Word Offset to the next hbin-Block
78 0x001C D-Word Block-size
80 The values in 0x0008 and 0x001C should be the same, so I don't know
81 if they are correct or swapped...
83 From offset 0x0020 inside a hbin-block data is stored with the following
87 0x0000 D-Word Data-block size //this size must be a
91 If the size field is negative (bit 31 set), the corresponding block
92 is free and has a size of -blocksize!
94 That does not seem to be true. All block lengths seem to be negative! (Richard Sharpe)
96 The data is stored as one record per block. Block size is a multiple
97 of 4 and the last block reaches the next hbin-block, leaving no room.
99 Records in the hbin-blocks
100 ==========================
104 The nk-record can be treated as a kombination of tree-record and
105 key-record of the win 95 registry.
109 The lf-record is the counterpart to the RGKN-record (the
114 The vk-record consists information to a single value.
118 sk (? Security Key ?) is the ACL of the registry.
122 The value-lists contain information about which values are inside a
123 sub-key and don't have a header.
127 The datas of the registry are (like the value-list) stored without a
130 All offset-values are relative to the first hbin-block and point to the
131 block-size field of the record-entry. to get the file offset, you have to add
132 the header size (4kb) and the size field (4 bytes)...
137 0x0000 Word ID: ASCII-"nk" = 0x6B6E
138 0x0002 Word for the root-key: 0x2C, otherwise 0x20 //key symbolic links 0x10. Nigel
139 0x0004 Q-Word write-date/time in windows nt notation
140 0x0010 D-Word Offset of Owner/Parent key
141 0x0014 D-Word number of sub-Keys
142 0x001C D-Word Offset of the sub-key lf-Records
143 0x0024 D-Word number of values
144 0x0028 D-Word Offset of the Value-List
145 0x002C D-Word Offset of the sk-Record
147 0x0030 D-Word Offset of the Class-Name //see NK structure for the use of these fields. Nigel
148 0x0044 D-Word Unused (data-trash) //some kind of run time index. Does not appear to be important. Nigel
149 0x0048 Word name-length
150 0x004A Word class-name length
156 0x0000 D-Word Offset 1st Value
157 0x0004 D-Word Offset 2nd Value
158 0x???? D-Word Offset nth Value
160 To determine the number of values, you have to look at the owner-nk-record!
165 0x0000 Word ID: ASCII-"vk" = 0x6B76
166 0x0002 Word name length
167 0x0004 D-Word length of the data //if top bit is set when offset contains data. Nigel
168 0x0008 D-Word Offset of Data
169 0x000C D-Word Type of value
171 0x0012 Word Unused (data-trash)
174 If bit 0 of the flag-word is set, a name is present, otherwise the value has no name (=default)
176 If the data-size is lower 5, the data-offset value is used to store the data itself!
181 0x0001 RegSZ: character string (in UNICODE!)
182 0x0002 ExpandSZ: string with "%var%" expanding (UNICODE!)
183 0x0003 RegBin: raw-binary value
184 0x0004 RegDWord: Dword
185 0x0007 RegMultiSZ: multiple strings, seperated with 0
191 0x0000 Word ID: ASCII-"lf" = 0x666C
192 0x0002 Word number of keys
193 0x0004 ???? Hash-Records
198 0x0000 D-Word Offset of corresponding "nk"-Record
199 0x0004 D-Word ASCII: the first 4 characters of the key-name, padded with 0's. Case sensitiv!
201 Keep in mind, that the value at 0x0004 is used for checking the data-consistency! If you change the
202 key-name you have to change the hash-value too!
204 //These hashrecords must be sorted low to high within the lf record. Nigel.
208 (due to the complexity of the SAM-info, not clear jet)
209 (This is just a security descriptor in the data. R Sharpe.)
213 0x0000 Word ID: ASCII-"sk" = 0x6B73
215 0x0004 D-Word Offset of previous "sk"-Record
216 0x0008 D-Word Offset of next "sk"-Record
217 0x000C D-Word usage-counter
218 0x0010 D-Word Size of "sk"-record in bytes
220 relative security desciptor. Nigel
221 ???? ???? Security and auditing settings...
224 The usage counter counts the number of references to this
225 "sk"-record. You can use one "sk"-record for the entire registry!
227 Windows nt date/time format
228 ===========================
229 The time-format is a 64-bit integer which is incremented every
230 0,0000001 seconds by 1 (I don't know how accurate it realy is!)
231 It starts with 0 at the 1st of january 1601 0:00! All values are
232 stored in GMT time! The time-zone is important to get the real
235 Common values for win95 and win-nt
236 ==================================
237 Offset values marking an "end of list", are either 0 or -1 (0xFFFFFFFF).
238 If a value has no name (length=0, flag(bit 0)=0), it is treated as the
240 If a value has no data (length=0), it is displayed as empty.
242 simplyfied win-3.?? registry:
243 =============================
246 | next rec. |---+ +----->+------------+
247 | first sub | | | | Usage cnt. |
248 | name | | +-->+------------+ | | length |
249 | value | | | | next rec. | | | text |------->+-------+
250 +-----------+ | | | name rec. |--+ +------------+ | xxxxx |
251 +------------+ | | value rec. |-------->+------------+ +-------+
252 v | +------------+ | Usage cnt. |
253 +-----------+ | | length |
254 | next rec. | | | text |------->+-------+
255 | first sub |------+ +------------+ | xxxxx |
260 Greatly simplyfied structure of the nt-registry:
261 ================================================
263 +---------------------------------------------------------------+
266 +---------+ +---------->+-----------+ +----->+---------+ |
267 | "nk" | | | lf-rec. | | | nk-rec. | |
268 | ID | | | # of keys | | | parent |---+
269 | Date | | | 1st key |--+ | .... |
270 | parent | | +-----------+ +---------+
272 | values |--------------------->+----------+
273 | SK-rec. |---------------+ | 1. value |--> +----------+
274 | class |--+ | +----------+ | vk-rec. |
275 +---------+ | | | .... |
276 v | | data |--> +-------+
277 +------------+ | +----------+ | xxxxx |
278 | Class name | | +-------+
281 +---------+ +---------+
282 +----->| next sk |--->| Next sk |--+
283 | +---| prev sk |<---| prev sk | |
284 | | | .... | | ... | |
285 | | +---------+ +---------+ |
288 | +--------------------+ |
289 +----------------------------------+
291 ---------------------------------------------------------------------------
293 Hope this helps.... (Although it was "fun" for me to uncover this things,
294 it took me several sleepless nights ;)
298 *************************************************************************/
303 #include <sys/types.h>
304 #include <sys/stat.h>
306 #include <sys/mman.h>
310 * These definitions are for the in-memory registry structure.
311 * It is a tree structure that mimics what you see with tools like regedit
315 * DateTime struct for Windows
318 typedef struct date_time_s
{
319 unsigned int low
, high
;
323 * Definition of a Key. It has a name, classname, date/time last modified,
324 * sub-keys, values, and a security descriptor
327 #define REG_ROOT_KEY 1
328 #define REG_SUB_KEY 2
330 typedef struct reg_key_s
{
331 char *name
; /* Name of the key */
333 int type
; /* One of REG_ROOT_KEY or REG_SUB_KEY */
334 NTTIME last_mod
; /* Time last modified */
335 struct reg_key_s
*owner
;
336 struct key_list_s
*sub_keys
;
337 struct val_list_s
*values
;
338 struct key_sec_desc_s
*security
;
342 * The KEY_LIST struct lists sub-keys.
345 typedef struct key_list_s
{
350 typedef struct val_key_s
{
355 void *data_blk
; /* Might want a separate block */
358 typedef struct val_list_s
{
364 #define MAXSUBAUTHS 15
367 typedef struct dom_sid_s
{
368 unsigned char ver
, auths
;
369 unsigned char auth
[6];
370 unsigned int sub_auths
[MAXSUBAUTHS
];
373 typedef struct ace_struct_s
{
374 unsigned char type
, flags
;
375 unsigned int perms
; /* Perhaps a better def is in order */
379 typedef struct acl_struct_s
{
380 unsigned short rev
, refcnt
;
381 unsigned short num_aces
;
385 typedef struct sec_desc_s
{
386 unsigned int rev
, type
;
387 DOM_SID
*owner
, *group
;
391 typedef struct key_sec_desc_s
{
392 struct key_sec_desc_s
*prev
, *next
;
399 * An API for accessing/creating/destroying items above
402 /* Make, delete keys */
404 int nt_delete_reg_key(REG_KEY
*key
)
411 * Create/delete key lists and add delete keys to/from a list, count the keys
416 * Create/delete value lists, add/delete values, count them
421 * Create/delete security descriptors, add/delete SIDS, count SIDS, etc.
422 * We reference count the security descriptors. Any new reference increments
423 * the ref count. If we modify an SD, we copy the old one, dec the ref count
424 * and make the change. We also want to be able to check for equality so
425 * we can reduce the number of SDs in use.
430 * Load and unload a registry file.
432 * Load, loads it into memory as a tree, while unload sealizes/flattens it
436 * Get the starting record for NT Registry file
439 /* A map of sk offsets in the regf to KEY_SEC_DESCs for quick lookup etc */
440 typedef struct sk_map_s
{
442 KEY_SEC_DESC
*key_sec_desc
;
446 * Where we keep all the regf stuff for one registry.
447 * This is the structure that we use to tie the in memory tree etc
448 * together. By keeping separate structs, we can operate on different
449 * registries at the same time.
450 * Currently, the SK_MAP is an array of mapping structure.
451 * Since we only need this on input and output, we fill in the structure
452 * as we go on input. On output, we know how many SK items we have, so
453 * we can allocate the structure as we need to.
454 * If you add stuff here that is dynamically allocated, add the
455 * appropriate free statements below.
458 #define REGF_REGTYPE_NONE 0
459 #define REGF_REGTYPE_NT 1
460 #define REGF_REGTYPE_W9X 2
462 typedef struct regf_struct_s
{
464 char *regfile_name
, *outfile_name
;
469 REG_KEY
*root
; /* Root of the tree for this file */
470 int sk_count
, sk_map_size
;
475 * Structures for dealing with the on-disk format of the registry
478 typedef unsigned int DWORD
;
479 typedef unsigned short WORD
;
481 #define REG_REGF_ID 0x66676572
483 typedef struct regf_block
{
484 DWORD REGF_ID
; /* regf */
492 DWORD first_key
; /* offset */
493 unsigned int dblk_size
;
494 DWORD uk7
[116]; /* 1 */
498 typedef struct hbin_sub_struct
{
503 #define REG_HBIN_ID 0x6E696268
505 typedef struct hbin_struct
{
506 DWORD HBIN_ID
; /* hbin */
514 HBIN_SUB_HDR hbin_sub_hdr
;
517 #define REG_NK_ID 0x6B6E
519 typedef struct nk_struct
{
537 char key_nam
[1]; /* Actual length determined by nam_len */
540 #define REG_SK_ID 0x6B73
542 typedef struct sk_struct
{
552 #define OFF(f) ((f) + 0x1000 + 4)
553 #define LOCN(f) (base + OFF(f))
555 typedef struct hash_struct
{
560 #define REG_LF_ID 0x666C
562 typedef struct lf_struct
{
565 struct hash_struct hr
[1]; /* Array of hash records, depending on key_count */
568 typedef DWORD VL_TYPE
[1]; /* Value list is an array of vk rec offsets */
570 #define REG_VK_ID 0x6B76
572 typedef struct vk_struct
{
575 DWORD dat_len
; /* If top-bit set, offset contains the data */
578 WORD flag
; /* =1, has name, else no name (=Default). */
580 char dat_name
[1]; /* Name starts here ... */
583 #define REG_TYPE_REGSZ 1
584 #define REG_TYPE_EXPANDSZ 2
585 #define REG_TYPE_BIN 3
586 #define REG_TYPE_DWORD 4
587 #define REG_TYPE_MULTISZ 7
589 #define OFF(f) ((f) + 0x1000 + 4)
590 #define LOCN(f) (base + OFF(f))
592 int nt_set_regf_input_file(REGF
*regf
, char *filename
)
594 return ((regf
->regfile_name
= strdup(filename
)) != NULL
);
597 int nt_set_regf_output_file(REGF
*regf
, char *filename
)
599 return ((regf
->outfile_name
= strdup(filename
)) != NULL
);
602 /* Create a regf structure and init it */
604 REGF
*nt_create_regf()
606 REGF
*tmp
= (REGF
*)malloc(sizeof(REGF
));
607 if (!tmp
) return tmp
;
608 bzero(tmp
, sizeof(REGF
));
612 /* Free all the bits and pieces ... Assumes regf was malloc'd */
613 /* If you add stuff to REGF, add the relevant free bits here */
614 int nt_free_regf(REGF
*regf
)
618 if (regf
->regfile_name
) free(regf
->regfile_name
);
619 if (regf
->outfile_name
) free(regf
->outfile_name
);
621 /* Free the mmap'd area */
623 if (regf
->base
) munmap(regf
->base
, regf
->sbuf
.st_size
);
625 close(regf
->fd
); /* Ignore the error :-) */
627 nt_delete_reg_key(regf
->root
); /* Free the tree */
629 regf
->sk_count
= regf
->sk_map_size
= 0;
635 /* Get the header of the registry
636 If the mmap'd area has not been allocated, then mmap the input file
638 int nt_get_regf_hdr(REGF
*regf
)
641 return -1; /* What about errors */
643 if (!regf
->regfile_name
)
644 return -1; /* What about errors */
646 if (!regf
->base
) { /* Try to mmap etc the file */
648 if ((regf
->fd
= open(regf
->regfile_name
, O_RDONLY
, 0000)) <0) {
649 return regf
->fd
; /* What about errors */
652 if (fstat(regf
->fd
, ®f
->sbuf
) < 0) {
656 regf
->base
= mmap(0, regf
->sbuf
.st_size
, PROT_READ
, MAP_SHARED
, regf
->fd
, 0);
658 if ((int)regf
->base
== 1) {
659 fprintf(stderr
, "Could not mmap file: %s, %s\n", regf
->regfile_name
,
666 * At this point, regf->base != NULL, and we should be able to read the
670 assert(regf
->base
!= NULL
);
677 int nt_get_hbin_hdr(REGF
*regf
, int hbin_offs
)
683 int nt_load_registry(REGF
*regf
)
689 if ((rc
= nt_get_regf_hdr(regf
)) < 0) {
699 * Main code from here on ...
704 fprintf(stderr
, "Usage: editreg <registryfile>\n");
705 fprintf(stderr
, "Version: 0.1\n\n");
708 int main(int argc
, char *argv
[])
717 if ((regf
= nt_create_regf()) == NULL
) {
718 fprintf(stderr
, "Could not create registry object: %s\n", strerror(errno
));
722 if (!nt_set_regf_input_file(regf
, argv
[1])) {
723 fprintf(stderr
, "Could not set name of registry file: %s, %s\n",
724 argv
[1], strerror(errno
));
728 /* Now, open it, and bring it into memory :-) */
730 if (nt_load_registry(regf
) < 0) {
731 fprintf(stderr
, "Could not load registry: %s\n", argv
[1]);