/********************************************************/

/*  ntapi: Native API core library                      */

/*  Copyright (C) 2013--2021  SysDeer Technologies, LLC */

/*  Released under GPLv2 and GPLv3; see COPYING.NTAPI.  */

/********************************************************/

#include <ntapi/ntapi.h>

#include <ntapi/nt_file.h>

#include "ntapi_impl.h"

int32_t __stdcall __ntapi_tt_open_physical_parent_directory(

	__out	void **		hparent,

	__in	void *		hdir,

	__out	void *		buffer,

	__in	uint32_t	buffer_size,

	__in	uint32_t	oattr,

	__in	uint32_t	desired_access,

	__in	uint32_t	share_access,

	__in	uint32_t	open_options,

	__out	int *		reserved)

{

	int32_t			status;

	nt_oa			oa;

	nt_iosb			iosb;

	wchar16_t *		wch;

	wchar16_t *		root;

	nt_unicode_string *	path;

	uint32_t		len;

	int			mup;

	uintptr_t		addr;

	uintptr_t		addr_cap;

	(void)reserved;

	addr     = (uintptr_t)buffer;

	addr_cap = addr + buffer_size;

	addr += 0xf;

	addr |= 0xf;

	addr ^= 0xf;

	path        = (nt_unicode_string *)addr;

	buffer_size = addr_cap - addr;

	if ((status = __ntapi->zw_query_object(

			hdir,

			NT_OBJECT_NAME_INFORMATION,

			path,

			buffer_size,

			&len)))

		return status;

	/* integrity */

	if (len == sizeof(nt_unicode_string))

		return NT_STATUS_BAD_FILE_TYPE;

	/* device root directory */

	root = path->buffer;

	wch  = path->buffer + (path->strlen / sizeof(uint16_t));

	if ((wch < &root[8])

			|| (root[0] != '\\')

			|| (root[1] != 'D') || (root[2] != 'e')

			|| (root[3] != 'v') || (root[4] != 'i')

			|| (root[5] != 'c') || (root[6] != 'e')

			|| (root[7] != '\\'))

		return NT_STATUS_INTERNAL_ERROR;

	mup = (wch > &root[11])

		&& (root[8]=='M')

		&& (root[9]=='u')

		&& (root[10]=='p')

		&& (root[11]=='\\');

	root = mup ? &root[12] : &root[8];

	for (; (root

		root++;

	if (root == wch)

		return NT_STATUS_INTERNAL_ERROR;

	if (mup)

		for (root++; (root

			root++;

	if (root == wch)

		return NT_STATUS_INTERNAL_ERROR;

	if (&root[1] == wch)

		return NT_STATUS_MORE_PROCESSING_REQUIRED;

	if (wch[-1] == '\\')

		wch--;

	/* physical parent directory path */

	for (root++; (wch>=root) && (wch[-1]!='\\'); )

		wch--;

	path->strlen = (uint16_t)(wch - path->buffer) * sizeof(uint16_t);

	path->maxlen = 0;

	/* oa */

	oa.len = sizeof(nt_oa);

	oa.root_dir = 0;

	oa.obj_name = path;

	oa.obj_attr = oattr,

	oa.sec_desc = 0;

	oa.sec_qos  = 0;

	/* default access */

	desired_access = desired_access

		? desired_access

		: NT_SEC_SYNCHRONIZE | NT_FILE_READ_ATTRIBUTES | NT_FILE_READ_ACCESS;

	/* open parent directory */

	return __ntapi->zw_open_file(

		hparent,

		desired_access,

		&oa,&iosb,

		share_access,

		open_options | NT_FILE_DIRECTORY_FILE);

}