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

/*  pemagination: a (virtual) tour into portable bits and executable bytes   */

/*  Copyright (C) 2013--2017  Z. Gilboa                                      */

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

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

#include <psxtypes/psxtypes.h>

#include <pemagine/pemagine.h>

#include "pe_os.h"

static int32_t pe_get_device_dos_drive_letter(

	void *			hntdll,

	os_zw_query_object *	zw_query_object,

	uintptr_t *		dbuffer,

	uint32_t		dbufsize,

	wchar16_t *		devname,

	size_t			devnamelen,

	wchar16_t *		letter)

{

	int32_t			status;

	void *			hdevice;

	int			sigh;

	size_t			idx;

	size_t			cap;

	uint32_t		len;

	struct os_oa		oa;

	struct os_iosb		iosb;

	wchar16_t *		src;

	wchar16_t *		dst;

	struct pe_unicode_str	path;

	struct pe_unicode_str * dpath;

	os_zw_open_file *	zw_open_file;

	os_zw_close *		zw_close;

	wchar16_t		namebuf[8] = {

				'\\','?','?','\\',

				'X',':','\\',0};

	unsigned char		letters[26] = {

				'C','Z','Y','X','W','V',

				'E','H','F','G','D','I',

				'P','Q','R','S','T','U',

				'J','K','L','M','N','O',

				'A','B'};

	/* init */

	if (!(zw_open_file = (os_zw_open_file *)pe_get_procedure_address(

			hntdll,"ZwOpenFile")))

		return OS_STATUS_INTERNAL_ERROR;

	if (!(zw_close = (os_zw_close *)pe_get_procedure_address(

			hntdll,"ZwClose")))

		return OS_STATUS_INTERNAL_ERROR;

	/* path */

	path.buffer = namebuf;

	path.strlen = 7 * sizeof(wchar16_t);

	path.maxlen = 0;

	/* oa */

	oa.len      = sizeof(struct os_oa);

	oa.root_dir = 0;

	oa.obj_name = &pat;;

	oa.obj_attr = 0;

	oa.sec_desc = 0;

	oa.sec_qos  = 0;

	/* just a few rounds of submissiveness */

	for (sigh=0; sigh<26; sigh++) {

		namebuf[4] = letters[sigh];

		status = zw_open_file(

			&hdevice,

			OS_SEC_SYNCHRONIZE

				| OS_FILE_READ_ATTRIBUTES

				| OS_FILE_READ_ACCESS,

			&oa,&iosb,

			OS_FILE_SHARE_READ

				| OS_FILE_SHARE_WRITE

				| OS_FILE_SHARE_DELETE,

			OS_FILE_DIRECTORY_FILE);

		if (status == OS_STATUS_SUCCESS) {

			status = zw_query_object(

				hdevice,

				OS_OBJECT_NAME_INFORMATION,

				dbuffer,dbufsize,&len;;

			if (status == OS_STATUS_SUCCESS) {

				dpath = (struct pe_unicode_str *)dbuffer;

				src = devname;

				dst = dpath->buffer;

				idx = 0;

				cap = devnamelen / sizeof(wchar16_t);

				for (; idx

					idx++;

				if (idx==cap && dst[idx]=='\\') {

					zw_close(hdevice);

					*letter = letters[sigh];

					return OS_STATUS_SUCCESS;

				}

			}

			zw_close(hdevice);

		}

	}

	return OS_STATUS_NOT_SUPPORTED;

}

int32_t pe_load_framework_loader(

	void **					baseaddr,

	struct pe_framework_runtime_data *	rtdata,

	uintptr_t *				buffer,

	uint32_t				bufsize,

	uint32_t *				flags)

{

	int32_t			status;

	struct pe_unicode_str	path;

	struct pe_unicode_str *	npath;

	uintptr_t		addr;

	uintptr_t *		dbuffer;

	uint32_t		dbufsize;

	wchar16_t *		ldrdir;

	wchar16_t *		slash;

	wchar16_t *		wch;

	wchar16_t *		cap;

	wchar16_t		letter;

	uint32_t		len;

	int			mup;

	void *			hntdll;

	os_zw_query_object *	zw_query_object;

	os_ldr_load_dll *	ldr_load_dll;

	/* init */

	if (!(hntdll = pe_get_ntdll_module_handle()))

		return OS_STATUS_INTERNAL_ERROR;

	if (!(zw_query_object = (os_zw_query_object *)pe_get_procedure_address(

			hntdll,"ZwQueryObject")))

		return OS_STATUS_INTERNAL_ERROR;

	if (!(ldr_load_dll = (os_ldr_load_dll *)pe_get_procedure_address(

			hntdll,"LdrLoadDll")))

		return OS_STATUS_INTERNAL_ERROR;

	/* loader native path */

	if ((status = zw_query_object(

			rtdata->hloader,

			OS_OBJECT_NAME_INFORMATION,

			buffer,bufsize,&len)))

		return status;

	/* integrity */

	if (len == sizeof(struct pe_unicode_str))

		return OS_STATUS_BAD_FILE_TYPE;

	/* first sigh */

	npath = (struct pe_unicode_str *)buffer;

	wch = npath->buffer;

	cap = npath->buffer + (npath->strlen / sizeof(wchar16_t));

	if ((cap < &wch[8])

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

			|| (wch[1] != 'D')

			|| (wch[2] != 'e')

			|| (wch[3] != 'v')

			|| (wch[4] != 'i')

			|| (wch[5] != 'c')

			|| (wch[6] != 'e')

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

		return OS_STATUS_NOT_SUPPORTED;

	mup = (cap > &wch[11])

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

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

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

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

	slash = mup ? &wch[12] : &wch[8];

	for (; (*slash != '\\') && (slash < cap); )

		slash++;

	if (slash == cap)

		return OS_STATUS_INTERNAL_ERROR;

	if (mup)

		for (++slash; (*slash != '\\') && (slash < cap); )

			slash++;

	if (slash == cap)

		return OS_STATUS_INTERNAL_ERROR;

	/* second sigh */

	addr  = (uintptr_t)cap;

	addr += sizeof(uintptr_t) - 1;

	addr /= sizeof(uintptr_t);

	addr *= sizeof(uintptr_t);

	dbuffer   = (uintptr_t *)addr;

	dbufsize  = bufsize;

	dbufsize -= (dbuffer - buffer) * sizeof(uintptr_t);

	if ((status = pe_get_device_dos_drive_letter(

			hntdll,

			zw_query_object,

			dbuffer,dbufsize,

			npath->buffer,

			(slash - npath->buffer) * sizeof(wchar16_t),

			&letter)))

		return status;

	slash    = &slash[-2];

	slash[0] = letter;

	slash[1] = ':';

	path.buffer = slash;

	path.strlen = (cap - slash) * sizeof(wchar16_t);

	/* third sigh */

	for (slash=cap; (slash > path.buffer) && (*slash != '\\'); )

		slash--;

	if (slash == path.buffer)

		return OS_STATUS_INTERNAL_ERROR;

	ldrdir = path.buffer;

	*slash = 0;

	path.strlen -= (++slash - ldrdir) * sizeof(wchar16_t);

	path.maxlen  = path.strlen;

	path.buffer  = slash;

	/* hoppla */

	return ldr_load_dll(

		ldrdir,flags,

		&path,baseaddr);

}