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

/*  ntapi: Native API core library                      */

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

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

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

#include <psxtypes/psxtypes.h>

#include <pemagine/pemagine.h>

#include <ntapi/nt_status.h>

#include <ntapi/nt_object.h>

#include <ntapi/nt_thread.h>

#include <ntapi/nt_process.h>

#include <ntapi/nt_string.h>

#include <ntapi/ntapi.h>

#include "ntapi_impl.h"

#define __PROCESS_PARAMS_GUARD_PAGE_SIZE  (0x1000)

int32_t	__stdcall __ntapi_tt_create_remote_process_params(

	__in	void *				hprocess,

	__out 	nt_process_parameters **	rprocess_params,

	__in	nt_unicode_string *		image_file,

	__in	nt_unicode_string *		dll_path		__optional,

	__in	nt_unicode_string *		current_directory	__optional,

	__in	nt_unicode_string *		command_line		__optional,

	__in	wchar16_t *			environment 		__optional,

	__in	nt_unicode_string *		window_title		__optional,

	__in	nt_unicode_string *		desktop_info		__optional,

	__in	nt_unicode_string *		shell_info		__optional,

	__in	nt_unicode_string *		runtime_data		__optional)

{

	#define __ALIGN_ALLOC_SIZE \

		process_params.alloc_size += sizeof(uintptr_t) - 1; \

		process_params.alloc_size /= sizeof(uintptr_t); \

		process_params.alloc_size *= sizeof(uintptr_t);

	int32_t		status;

	ptrdiff_t	d_image;

	ptrdiff_t	d_dll_path;

	ptrdiff_t	d_cwd;

	ptrdiff_t	d_cmd_line;

	ptrdiff_t	d_environment;

	ptrdiff_t	d_runtime;

	/*

	ptrdiff_t	d_wnd_title;

	ptrdiff_t	d_desktop;

	ptrdiff_t	d_shell;

	*/

	wchar16_t *	wch;

	size_t		env_block_size;

	size_t		params_block_size;

	size_t		bytes_written;

	nt_process_parameters	process_params;

	nt_process_parameters *	params_block;

	nt_process_parameters *	rparams_block;

	nt_process_parameters *	params_default;

	/* unused params */

	(void)window_title;

	(void)desktop_info;

	(void)shell_info;

	/* make the compiler happy */

	d_image		= 0;

	d_dll_path	= 0;

	d_cwd		= 0;

	d_cmd_line	= 0;

	d_environment	= 0;

	d_runtime	= 0;

	env_block_size	= 0;

	/* initialize */

	__ntapi->tt_aligned_block_memset(

		&process_params,

		0,sizeof(nt_process_parameters));

	/* allow for extended structures (newer OS versions) */

	process_params.alloc_size = sizeof(nt_process_parameters)

					+ 8 * sizeof(uintptr_t);

	params_default = ((nt_peb *)pe_get_peb_address())->process_params;

	/* image_file */

	if (image_file) {

		/* check alignment and sanity */

		if ((uintptr_t)image_file->buffer % sizeof(uintptr_t))

			return NT_STATUS_INVALID_PARAMETER_2;

		else if (image_file->maxlen < image_file->strlen)

			return NT_STATUS_INVALID_PARAMETER_2;

		process_params.image_file_name.strlen = image_file->strlen;

		process_params.image_file_name.maxlen = image_file->maxlen;

		/* store offset and update alloc_size */

		d_image = process_params.alloc_size;

		process_params.alloc_size += image_file->maxlen;

		__ALIGN_ALLOC_SIZE;

	}

	/* dll_path */

	if (!dll_path)

		dll_path = &(params_default->dll_path);

	if (dll_path) {

		/* check alignment and sanity */

		if ((uintptr_t)dll_path->buffer % sizeof(uintptr_t))

			return NT_STATUS_INVALID_PARAMETER_3;

		else if (dll_path->maxlen < dll_path->strlen)

			return NT_STATUS_INVALID_PARAMETER_3;

		process_params.dll_path.strlen = dll_path->strlen;

		process_params.dll_path.maxlen = dll_path->maxlen;

		/* store offset and update alloc_size */

		d_dll_path = process_params.alloc_size;

		process_params.alloc_size += dll_path->maxlen;

		__ALIGN_ALLOC_SIZE;

	}

	/* current_directory */

	if (!current_directory)

		current_directory = &(params_default->cwd_name);

	if (current_directory) {

		/* check alignment and sanity */

		if ((uintptr_t)current_directory->buffer % sizeof(uintptr_t))

			return NT_STATUS_INVALID_PARAMETER_4;

		else if (current_directory->maxlen < current_directory->strlen)

			return NT_STATUS_INVALID_PARAMETER_4;

		process_params.cwd_name.strlen = current_directory->strlen;

		process_params.cwd_name.maxlen = current_directory->maxlen;

		/* store offset and update alloc_size */

		d_cwd = process_params.alloc_size;

		process_params.alloc_size += current_directory->maxlen;

		__ALIGN_ALLOC_SIZE;

	}

	/* command_line */

	if (command_line) {

		/* check alignment and sanity */

		if ((uintptr_t)command_line->buffer % sizeof(uintptr_t))

			return NT_STATUS_INVALID_PARAMETER_5;

		else if (command_line->maxlen < command_line->strlen)

			return NT_STATUS_INVALID_PARAMETER_5;

		process_params.command_line.strlen = command_line->strlen;

		process_params.command_line.maxlen = command_line->maxlen;

		/* store offset and update alloc_size */

		d_cmd_line = process_params.alloc_size;

		process_params.alloc_size += command_line->maxlen;

		__ALIGN_ALLOC_SIZE;

	}

	/* environment */

	if (environment) {

		/* check alignment */

		if ((uintptr_t)environment % sizeof(uintptr_t))

			return NT_STATUS_INVALID_PARAMETER_6;

		/* obtain size of environment block */

		wch = environment;

		while (*wch) {

			/* reach the end of the current variable */

			while (*wch++)

			/* proceed to the next variable */

			wch++;

		}

		env_block_size = (uintptr_t)wch - (uintptr_t)environment;

		/* store offset and update alloc_size */

		d_environment = process_params.alloc_size;

		process_params.alloc_size += (uint32_t)env_block_size;

		process_params.alloc_size += __PROCESS_PARAMS_GUARD_PAGE_SIZE;

		__ALIGN_ALLOC_SIZE;

	}

	/* runtime_data */

	if (runtime_data) {

		/* check alignment and sanity */

		if ((uintptr_t)runtime_data->buffer % sizeof(uintptr_t))

			return NT_STATUS_INVALID_PARAMETER_5;

		else if (runtime_data->maxlen < runtime_data->strlen)

			return NT_STATUS_INVALID_PARAMETER_5;

		process_params.runtime_data.strlen = runtime_data->strlen;

		process_params.runtime_data.maxlen = runtime_data->maxlen;

		/* store offset and update alloc_size */

		d_runtime = process_params.alloc_size;

		process_params.alloc_size += runtime_data->maxlen;

		__ALIGN_ALLOC_SIZE;

	}

	/* allocate local and remote process parameters blocks */

	params_block = (nt_process_parameters *)0;

	rparams_block = (nt_process_parameters *)0;

	process_params.used_size = process_params.alloc_size;

	params_block_size = process_params.alloc_size;

	/* local block */

	status = __ntapi->zw_allocate_virtual_memory(

		NT_CURRENT_PROCESS_HANDLE,

		(void **)&params_block,

		0,

		&params_block_size,

		NT_MEM_COMMIT,

		NT_PAGE_READWRITE);

	if (status != NT_STATUS_SUCCESS)

		return status;

	process_params.alloc_size = (uint32_t)params_block_size;

	__ntapi->tt_aligned_block_memset(params_block,0,params_block_size);

	/* remote block */

	status = __ntapi->zw_allocate_virtual_memory(

		hprocess,

		(void **)&rparams_block,

		0,

		&params_block_size,

		NT_MEM_RESERVE | NT_MEM_COMMIT,

		NT_PAGE_READWRITE);

	if (status != NT_STATUS_SUCCESS) {

		__ntapi->zw_free_virtual_memory(

			NT_CURRENT_PROCESS_HANDLE,

			(void **)&params_block,

			(size_t *)&process_params.alloc_size,

			NT_MEM_RELEASE);

		return status;

	}

	/* copy the process_params structure */

	__ntapi->tt_aligned_memcpy_utf16(

		(uintptr_t *)params_block,

		(uintptr_t *)&process_params,

		sizeof(nt_process_parameters));

	/* image_file */

	if (image_file) {

		params_block->image_file_name.buffer =

			(uint16_t *)pe_va_from_rva(rparams_block,d_image);

		__ntapi->tt_aligned_memcpy_utf16(

			(uintptr_t *)pe_va_from_rva(params_block,d_image),

			(uintptr_t *)image_file->buffer,

			image_file->strlen);

	}

	/* dll_path */

	if (dll_path) {

		params_block->dll_path.buffer =

			(uint16_t *)pe_va_from_rva(rparams_block,d_dll_path);

		__ntapi->tt_aligned_memcpy_utf16(

			(uintptr_t *)pe_va_from_rva(params_block,d_dll_path),

			(uintptr_t *)dll_path->buffer,

			dll_path->strlen);

	}

	/* current_directory */

	if (current_directory) {

		params_block->cwd_name.buffer =

			(uint16_t *)pe_va_from_rva(rparams_block,d_cwd);

		__ntapi->tt_aligned_memcpy_utf16(

			(uintptr_t *)pe_va_from_rva(params_block,d_cwd),

			(uintptr_t *)current_directory->buffer,

			current_directory->strlen);

	}

	/* command_line */

	if (command_line) {

		params_block->command_line.buffer =

			(uint16_t *)pe_va_from_rva(rparams_block,d_cmd_line);

		__ntapi->tt_aligned_memcpy_utf16(

			(uintptr_t *)pe_va_from_rva(params_block,d_cmd_line),

			(uintptr_t *)command_line->buffer,

			command_line->strlen);

	}

	/* environment */

	if (environment) {

		params_block->environment =

			(wchar16_t *)pe_va_from_rva(rparams_block,d_environment);

		__ntapi->tt_aligned_memcpy_utf16(

			(uintptr_t *)pe_va_from_rva(params_block,d_environment),

			(uintptr_t *)environment,

			env_block_size);

	}

	/* runtime_data */

	if (runtime_data) {

		params_block->runtime_data.buffer =

			(uint16_t *)pe_va_from_rva(rparams_block,d_runtime);

		__ntapi->tt_aligned_memcpy_utf16(

			(uintptr_t *)pe_va_from_rva(params_block,d_runtime),

			(uintptr_t *)runtime_data->buffer,

			runtime_data->strlen);

	}

	params_block->flags = 1; /* normalized */

	/* copy the local params block to the remote process */

	status = __ntapi->zw_write_virtual_memory(

		hprocess,

		rparams_block,

		(char *)params_block,

		process_params.alloc_size,

		&bytes_written);

	if (status != NT_STATUS_SUCCESS)

		return status;

	/* free the local params block */

	__ntapi->zw_free_virtual_memory(

		NT_CURRENT_PROCESS_HANDLE,

		(void **)&params_block,

		(size_t *)&process_params.alloc_size,

		NT_MEM_RELEASE);

	/* all done */

	*rprocess_params = rparams_block;

	return NT_STATUS_SUCCESS;

}