/*
 * Unix SMB/CIFS implementation.
 * Windows NT registry I/O library
 * Copyright (c) Gerald (Jerry) Carter               2005
 *
 * 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.
 */

/************************************************************
 * Most of this information was obtained from 
 * http://www.wednesday.demon.co.uk/dosreg.html
 * Thanks Nigel!
 ***********************************************************/


#ifndef _REGFIO_H
#define _REGFIO_H

/* Macros */
 
#define REGF_BLOCKSIZE		0x1000
#define REGF_ALLOC_BLOCK	0x1000

/* header sizes for various records */

#define REGF_HDR_SIZE		4
#define HBIN_HDR_SIZE		4
#define HBIN_HEADER_REC_SIZE	0x24
#define REC_HDR_SIZE		2

#define REGF_OFFSET_NONE	0xffffffff

/* Flags for the vk records */

#define VK_FLAG_NAME_PRESENT	0x0001
#define VK_DATA_IN_OFFSET	0x80000000

/* NK record macros */

#define NK_TYPE_LINKKEY		0x0010
#define NK_TYPE_NORMALKEY	0x0020
#define NK_TYPE_ROOTKEY		0x002c

#define HBIN_STORE_REF(x, y)	{ x->hbin = y; y->ref_count++ };
#define HBIN_REMOVE_REF(x, y)	{ x->hbin = NULL; y->ref_count-- /* if the count == 0; we can clean up */ };


/* HBIN block */
struct regf_hbin;
typedef struct regf_hbin {
	struct regf_hbin *prev, *next;
	uint32 file_off;		/* my offset in the registry file */
	uint32 free_off;		/* offset to free space within the hbin record */
	uint32 free_size;		/* amount of data left in the block */
	int ref_count;			/* how many active records are pointing to this block (not used currently) */
	
	char   header[HBIN_HDR_SIZE];	/* "hbin" */
	uint32 first_hbin_off;		/* offset from first hbin block */
	uint32 block_size;		/* block size of this blockually a multiple of 4096Kb) */

	prs_struct ps;			/* data */

	BOOL dirty;			/* has this hbin block been modified? */
} REGF_HBIN;

/* ??? List -- list of key offsets and hashed names for consistency */

typedef struct {
	uint32 nk_off;
	uint8 keycheck[sizeof(uint32)];
} REGF_HASH_REC;

typedef struct {
	REGF_HBIN *hbin;	/* pointer to HBIN record (in memory) containing this nk record */
	uint32 hbin_off;	/* offset from beginning of this hbin block */
	uint32 rec_size;	/* ((start_offset - end_offset) & 0xfffffff8) */

	char header[REC_HDR_SIZE];
	uint16 num_keys;
	REGF_HASH_REC *hashes;
} REGF_LF_REC;

/* Key Value */

typedef struct {
	REGF_HBIN *hbin;	/* pointer to HBIN record (in memory) containing this nk record */
	uint32 hbin_off;	/* offset from beginning of this hbin block */
	uint32 rec_size;	/* ((start_offset - end_offset) & 0xfffffff8) */
	uint32 rec_off;		/* offset stored in the value list */
	
	char header[REC_HDR_SIZE];
	char *valuename;
	uint32 data_size;
	uint32 data_off;
	uint8  *data;
	uint32 type;
	uint16 flag;
} REGF_VK_REC;


/* Key Security */
struct _regf_sk_rec;

typedef struct _regf_sk_rec {
	struct _regf_sk_rec *next, *prev;
	REGF_HBIN *hbin;	/* pointer to HBIN record (in memory) containing this nk record */
	uint32 hbin_off;	/* offset from beginning of this hbin block */
	uint32 rec_size;	/* ((start_offset - end_offset) & 0xfffffff8) */

	uint32 sk_off;		/* offset parsed from NK record used as a key
				   to lookup reference to this SK record */

	char header[REC_HDR_SIZE];
	uint32 prev_sk_off;
	uint32 next_sk_off;
	uint32 ref_count;
	uint32 size;
	SEC_DESC *sec_desc;
} REGF_SK_REC;

/* Key Name */ 

typedef struct {
	REGF_HBIN *hbin;	/* pointer to HBIN record (in memory) containing this nk record */
	uint32 hbin_off;	/* offset from beginning of this hbin block */
	uint32 subkey_index;	/* index to next subkey record to return */
	uint32 rec_size;	/* ((start_offset - end_offset) & 0xfffffff8) */
	
	/* header information */
	
	char header[REC_HDR_SIZE];
	uint16 key_type;
	NTTIME mtime;
	uint32 parent_off;	/* back pointer in registry hive */
	uint32 classname_off;	
	char *classname;
	char *keyname;

	/* max lengths */

	uint32 max_bytes_subkeyname;		/* max subkey name * 2 */
	uint32 max_bytes_subkeyclassname;	/* max subkey classname length (as if) */
	uint32 max_bytes_valuename;		/* max valuename * 2 */
	uint32 max_bytes_value;			/* max value data size */

	/* unknowns */

	uint32 unk_index;			/* nigel says run time index ? */
	
	/* children */
	
	uint32 num_subkeys;
	uint32 subkeys_off;	/* hash records that point to NK records */	
	uint32 num_values;
	uint32 values_off;	/* value lists which point to VK records */
	uint32 sk_off;		/* offset to SK record */
	
	/* link in the other records here */
	
	REGF_LF_REC subkeys;
	REGF_VK_REC *values;
	REGF_SK_REC *sec_desc;
	
} REGF_NK_REC;

/* REGF block */
 
typedef struct {
	/* run time information */

	int fd;				/* file descriptor */
	int open_flags;			/* flags passed to the open() call */
	TALLOC_CTX *mem_ctx;		/* memory context for run-time file access information */
	REGF_HBIN *block_list;		/* list of open hbin blocks */

	/* file format information */

	char   header[REGF_HDR_SIZE];	/* "regf" */
	uint32 data_offset;		/* offset to record in the first (or any?) hbin block */
	uint32 last_block;		/* offset to last hbin block in file */
	uint32 checksum;		/* XOR of bytes 0x0000 - 0x01FB */
	NTTIME mtime;
	
	REGF_SK_REC *sec_desc_list;	/* list of security descriptors referenced by NK records */

	/* unknowns used to simply writing */
	
	uint32 unknown1;
	uint32 unknown2;
	uint32 unknown3;
	uint32 unknown4;
	uint32 unknown5;
	uint32 unknown6;
	
} REGF_FILE;

/* Function Declarations */
 
REGF_FILE*    regfio_open( const char *filename, int flags, int mode );
int           regfio_close( REGF_FILE *r );

REGF_NK_REC*  regfio_rootkey( REGF_FILE *file );
REGF_NK_REC*  regfio_fetch_subkey( REGF_FILE *file, REGF_NK_REC *nk );
REGF_NK_REC*  regfio_write_key ( REGF_FILE *file, const char *name,
                                 REGVAL_CTR *values, REGSUBKEY_CTR *subkeys,
                                 SEC_DESC *sec_desc, REGF_NK_REC *parent );


#endif	/* _REGFIO_H */