/********************************************************/
/*  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 <ntapi/nt_memory.h>
#include <ntapi/nt_process.h>
#include <ntapi/ntapi.h>
#include "ntapi_impl.h"

typedef struct _nt_process_basic_information nt_pbi;

int32_t __stdcall __ntapi_tt_create_remote_runtime_data(
	__in		void *			hprocess,
	__in_out	nt_runtime_data_block *	rtblock)
{
	int32_t			status;

	size_t			bytes_written;
	nt_pbi			rpbi;
	nt_process_parameters *	rprocess_params;
	nt_unicode_string	rcmd_line;
	uint32_t		runtime_arg_hash;
	nt_runtime_data *	rtdata;
	void *			hserver;

	#if (__SIZEOF_POINTER__ == 4)
	wchar16_t		runtime_arg[8] = {
		'i','n','t','e','g','r','a','l'};
	#elif (__SIZEOF_POINTER__ == 8)
	wchar16_t		runtime_arg[16] = {
		'i','n','t','e','g','r','a','l',
		'-','r','u','n','t','i','m','e'};
	#endif

	/* validation */
	if (!hprocess)
		return NT_STATUS_INVALID_PARAMETER_1;
	else if (!rtblock)
		return NT_STATUS_INVALID_PARAMETER_2;
	else if (!rtblock->addr)
		return NT_STATUS_INVALID_PARAMETER_2;
	else if (!rtblock->size)
		return NT_STATUS_INVALID_PARAMETER_2;

	runtime_arg_hash = __ntapi->tt_buffer_crc32(
		0,
		(char *)runtime_arg,
		sizeof(runtime_arg));

	/* obtain process information */
	if ((status = __ntapi->zw_query_information_process(
			hprocess,
			NT_PROCESS_BASIC_INFORMATION,
			(void *)&rpbi,
			sizeof(nt_process_basic_information),
			0)))
		return status;

	if ((status = __ntapi->zw_read_virtual_memory(
			hprocess,
			pe_va_from_rva(
				rpbi.peb_base_address,
				(uintptr_t)&(((nt_peb *)0)->process_params)),
			(char *)&rprocess_params,
			sizeof(uintptr_t),
			&bytes_written)))
		return status;

	if ((status = __ntapi->zw_read_virtual_memory(
			hprocess,
			&rprocess_params->command_line,
			(char *)&rcmd_line,
			sizeof(nt_unicode_string),
			&bytes_written)))
		return status;

	if (rcmd_line.buffer == 0)
		return NT_STATUS_BUFFER_TOO_SMALL;

	if (rcmd_line.strlen < sizeof(runtime_arg) + 4*sizeof(wchar16_t))
		return NT_STATUS_INVALID_USER_BUFFER;

	if ((status = __ntapi->zw_read_virtual_memory(
			hprocess,
			pe_va_from_rva(
				rcmd_line.buffer,
				rcmd_line.strlen - sizeof(runtime_arg)),
			(char *)&runtime_arg,
			sizeof(runtime_arg),
			&bytes_written)))
		return status;

	/* verify remote process compatibility */
	runtime_arg_hash ^= __ntapi->tt_buffer_crc32(
		0,(char *)runtime_arg,
		sizeof(runtime_arg));

	if (runtime_arg_hash)
		return NT_STATUS_INVALID_SIGNATURE;

	/* remote block */
	rtblock->remote_size = rtblock->size;

	if ((status = __ntapi->zw_allocate_virtual_memory(
			hprocess,
			&rtblock->remote_addr,
			0,
			&rtblock->remote_size,
			NT_MEM_RESERVE | NT_MEM_COMMIT,
			NT_PAGE_READWRITE)))
		return status;

	/* session handles */
	rtdata    = 0;
	hserver   = 0;

	if (rtblock->flags & NT_RUNTIME_DATA_DUPLICATE_SESSION_HANDLES) {
		rtdata    = (nt_runtime_data *)rtblock->addr;
		hserver = rtdata->hserver;

		if ((status = __ntapi->zw_duplicate_object(
				NT_CURRENT_PROCESS_HANDLE,
				hserver,
				hprocess,
				&rtdata->hserver,
				0,0,
				NT_DUPLICATE_SAME_ATTRIBUTES
				|NT_DUPLICATE_SAME_ACCESS)))
			return status;
	}

	/* copy local block to remote process */
	status = __ntapi->zw_write_virtual_memory(
		hprocess,
		rtblock->remote_addr,
		(char *)rtblock->addr,
		rtblock->size,
		&bytes_written);

	/* restore rtdata */
	if (rtdata)
		rtdata->hserver = hserver;

	/* verify above remote write */
	if (status)
		return status;

	/* runtime_arg */
	__ntapi->tt_uintptr_to_hex_utf16(
		(uintptr_t)rtblock->remote_addr,
		runtime_arg);

	/* update remote runtime arg */
	status = __ntapi->zw_write_virtual_memory(
		hprocess,
		pe_va_from_rva(
			rcmd_line.buffer,
			rcmd_line.strlen - sizeof(runtime_arg)),
		(char *)&runtime_arg,
		sizeof(runtime_arg),
		&bytes_written);

	if (status)
		__ntapi->zw_free_virtual_memory(
			hprocess,
			&rtblock->remote_addr,
			&rtblock->remote_size,
			NT_MEM_RELEASE);

	return status;
}