/*********************************************************/
/*  toksvc: a framework-native token broker service      */
/*  Copyright (C) 2020  SysDeer Technologies, LLC        */
/*  Released under GPLv2 and GPLv3; see COPYING.TOKSVC.  */
/*********************************************************/

#include <psxtypes/psxtypes.h>
#include <ntapi/ntapi.h>

#include <toksvc/toksvc.h>
#include "toksvc_daemon_impl.h"
#include "toksvc_driver_impl.h"
#include "toksvc_log_impl.h"

#define  TOKS_VTBL_ELEMENTS   TOKS_DAEMON_OPCODE_CAP - TOKS_DAEMON_OPCODE_BASE

#define  TOKS_OPCODE_IDX(IDX) TOKS_DAEMON_ ## IDX - TOKS_DAEMON_OPCODE_BASE
#define  TOKS_HANDLER(IDX,fn) [TOKS_OPCODE_IDX(IDX)] = fn


static toks_daemon_routine * toks_daemon_vtbl[TOKS_VTBL_ELEMENTS] = {
	TOKS_HANDLER(CONNECT,       toks_daemon_connect),
	TOKS_HANDLER(CIDQUERY,      toks_daemon_cidquery),
	TOKS_HANDLER(TTYSIGNAL,     toks_daemon_signal),
	TOKS_HANDLER(ACQUIRE,       toks_daemon_acquire),
	TOKS_HANDLER(RELEASE,       toks_daemon_release),
	TOKS_HANDLER(CANCEL,        toks_daemon_cancel),
	TOKS_HANDLER(ABORT,         toks_daemon_abort),
	TOKS_HANDLER(IOCTL,         toks_daemon_ioctl),
};

static toks_daemon_routine * toks_client_vtbl[TOKS_VTBL_ELEMENTS] = {
	TOKS_HANDLER(CONNECT,       toks_daemon_connect),
	TOKS_HANDLER(CIDQUERY,      toks_daemon_cidquery),
	TOKS_HANDLER(TTYSIGNAL,     toks_daemon_signal),
};

static void toks_daemon_ctrlpid_abort(struct toks_daemon_ctx * dctx)
{
	void *			hport;
	struct _nt_tty_sync_msg	msg;

	hport = dctx->hport_internal_client;

	ntapi->tt_aligned_block_memset(
		&msg,0,sizeof(msg));

	msg.header.msg_type	= NT_LPC_NEW_MESSAGE;
	msg.header.data_size	= sizeof(msg.data);
	msg.header.msg_size	= sizeof(msg);
	msg.data.ttyinfo.opcode	= TOKS_DAEMON_ABORT;

	ntapi->zw_request_wait_reply_port(
		hport,&msg,&msg);
}

static int32_t toks_daemon_ctrlpid_wait(void * rapunzel)
{
	struct toks_daemon_ctx * dctx;

	dctx = (struct toks_daemon_ctx *)rapunzel;

	ntapi->zw_set_event(
		dctx->hswap,0);

	ntapi->zw_wait_for_single_object(
		dctx->hctrl,
		NT_SYNC_NON_ALERTABLE,
		0);

	toks_daemon_ctrlpid_abort(dctx);

	return ntapi->zw_terminate_thread(
		NT_CURRENT_THREAD_HANDLE,
		NT_STATUS_REMOTE_DISCONNECT);

}

static int32_t toks_daemon_ctrlpid_instance(struct toks_daemon_ctx * dctx)
{
	int32_t			status;
	nt_thread_params	params;
	nt_cid			cid;
	nt_oa			oa;

	if ((dctx->ctrlpid == 0) && (dctx->csyspid == 0))
		return NT_STATUS_SUCCESS;

	if (dctx->ctrlpid) {
		dctx->reqtokpid = dctx->ctrlpid;

		if ((status = toks_daemon_pidopen(dctx)))
			return status;

		dctx->csyspid = dctx->reqsyspid;
	}

	oa.len      = sizeof(oa);
	oa.root_dir = 0;
	oa.obj_name = 0;
	oa.obj_attr = 0;
	oa.sec_desc = 0;
	oa.sec_qos  = 0;

	cid.process_id = dctx->csyspid;
	cid.thread_id  = 0;

	if ((status = ntapi->zw_open_process(
			&dctx->hctrl,
			NT_PROCESS_SYNCHRONIZE,
			&oa,&cid)))
		return status;

	if ((status = ntapi->tt_create_private_event(
			&dctx->hswap,
			NT_NOTIFICATION_EVENT,
			NT_EVENT_NOT_SIGNALED)))
		return status;

	ntapi->tt_aligned_block_memset(
		&params,0,sizeof(params));

	params.hprocess		  = NT_CURRENT_PROCESS_HANDLE;
	params.start		  = toks_daemon_ctrlpid_wait;
	params.arg                = dctx;
	params.stack_size_commit  = 4 * 1024;
	params.stack_size_reserve = 4 * 1024;
	params.creation_flags	  = NT_CREATE_LOCAL_THREAD;

	if ((status = ntapi->tt_create_thread(&params))) {
		ntapi->zw_close(dctx->hctrl);
		ntapi->zw_close(dctx->hswap);
		return status;
	}

	status = ntapi->zw_wait_for_single_object(
		dctx->hswap,
		NT_SYNC_NON_ALERTABLE,
		0);

	ntapi->zw_close(dctx->hswap);
	ntapi->zw_close(params.hthread);

	if (status) {
		ntapi->zw_close(dctx->hctrl);
		return status;
	}

	return NT_STATUS_SUCCESS;
}

int32_t __stdcall toks_daemon_loop(void * ctx)
{
	struct toks_daemon_ctx *	dctx;
	toks_daemon_routine **		svcvtbl;
	nt_rtdata *			rtdata;

	nt_tty_port_msg *		request;
	nt_tty_port_msg *		reply;

	intptr_t			port_id;
	int32_t				opcode;
	int32_t				status;

	/* runtime data */
	if (ntapi->tt_get_runtime_data(&rtdata,0))
		return NT_STATUS_INTERNAL_ERROR;

	/* daemon context and controlling (system) process */
	dctx = (struct toks_daemon_ctx *)ctx;

	dctx->ctrlpid = toks_get_driver_ctrlpid(dctx->driver_ctx);
	dctx->csyspid = toks_get_driver_csyspid(dctx->driver_ctx);
	dctx->ftokens = toks_get_driver_ntokens(dctx->driver_ctx);

	svcvtbl = (dctx->driver_ctx->cctx->drvflags & TOKS_DRIVER_MODE_SERVER)
		? toks_daemon_vtbl
		: toks_client_vtbl;

	if (svcvtbl == toks_daemon_vtbl)
		if ((status = toks_daemon_ctrlpid_instance(dctx)))
			ntapi->zw_terminate_process(
				NT_CURRENT_PROCESS_HANDLE,
				status);

	/* service synchronization */
	if (rtdata->hsync) {
		ntapi->zw_set_event(rtdata->hsync,0);
		ntapi->zw_close(rtdata->hsync);
	}

	/* service info */
	if (svcvtbl == toks_daemon_vtbl)
		toks_log_service_info(dctx);

	/* init */
	request = &dctx->request;
	reply   = &dctx->reply;

	ntapi->tt_aligned_block_memset(
		request,0,sizeof(*request));

	/* get first message */
	ntapi->zw_reply_wait_receive_port(
		dctx->hport_daemon,
		&port_id,
		0,(nt_port_message *)request);

	/* message loop */
	do {
		switch (request->header.msg_type) {
			case NT_LPC_REQUEST:
			case NT_LPC_DATAGRAM:
				opcode = request->ttyinfo.opcode;
				break;

			case NT_LPC_CONNECTION_REQUEST:
				opcode = TOKS_DAEMON_CONNECT;
				break;

			default:
				opcode = -1;
				break;
		}

		/* dispatch */
		dctx->opcode = opcode;
		dctx->noise++;

		request->syncinfo.ipcsvc.keys.padding = 0;

		if (svcvtbl == toks_daemon_vtbl)
			toks_log_lpc_request(
				dctx,request);

		ntapi->tt_aligned_block_memcpy(
			(uintptr_t *)reply,
			(uintptr_t *)request,
			sizeof(*reply));

		reply->header.msg_type = NT_LPC_REPLY;

		switch (opcode) {
			case TOKS_DAEMON_IOCTL:
				break;

			default:
				reply->ttyinfo.opdata = reply->header.msg_id;
		}

		if ((opcode >= TOKS_DAEMON_OPCODE_BASE) && (opcode < TOKS_DAEMON_OPCODE_CAP)) {
			opcode -= TOKS_DAEMON_OPCODE_BASE;
			reply->ttyinfo.status = svcvtbl[opcode]
				? svcvtbl[opcode](dctx)
				: NT_STATUS_NOT_IMPLEMENTED;
		} else {
			reply->ttyinfo.status   = NT_STATUS_LPC_INVALID_CONNECTION_USAGE;
		}

		if (svcvtbl == toks_daemon_vtbl)
			toks_log_lpc_reply(
				dctx,reply);

		ntapi->tt_aligned_block_memset(
			request,0,sizeof(*request));

		if (!reply->ttyinfo.opdata)
			ntapi->zw_reply_wait_receive_port(
				dctx->hport_daemon,
				&port_id,
				0,&request->header);
		else if (reply->header.client_id.process_id == rtdata->cid_self.process_id)
			ntapi->zw_reply_wait_receive_port(
				dctx->hport_daemon,
				&port_id,
				&reply->header,
				&request->header);
		else {
			ntapi->zw_reply_port(
				dctx->hport_daemon,
				&reply->header);

			ntapi->zw_reply_wait_receive_port(
				dctx->hport_daemon,
				&port_id,
				0,&request->header);
		}
	} while (request->header.msg_id);

	return NT_STATUS_INTERNAL_ERROR;
}