/* Copyright (C) 2015 Open Information Security Foundation

 *

 * You can copy, redistribute or modify this Program under the terms of

 * the GNU General Public License version 2 as published by the Free

 * Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * version 2 along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA

 * 02110-1301, USA.

 */

#include "suricata-common.h"

#include "app-layer-dnp3.h"

#include "app-layer-dnp3-objects.h"

#include "lua.h"

#include "lualib.h"

#include "lauxlib.h"

#include "util-lua.h"

#include "util-lua-common.h"

#include "util-lua-dnp3.h"

#include "util-lua-dnp3-objects.h"

/**

 * \brief Helper macro to push key and integer value onto a table.

 */

#define LUA_PUSHT_INT(l, k, v) do {             \

        lua_pushliteral(luastate, k);           \

        lua_pushinteger(luastate, v);           \

        lua_settable(luastate, -3);             \

    } while (0);

static void SCLuaPushTableBoolean(lua_State *L, const char *key, bool val)

{

    lua_pushstring(L, key);

    lua_pushboolean(L, val);

    lua_settable(L, -3);

}

static void DNP3PushPoints(lua_State *luastate, DNP3Object *object)

{

    DNP3Point *point;

    int i = 1;

    TAILQ_FOREACH(point, object->points, next) {

        lua_pushinteger(luastate, i++);

        lua_newtable(luastate);

        lua_pushliteral(luastate, "index");

        lua_pushinteger(luastate, point->index);

        lua_settable(luastate, -3);

        DNP3PushPoint(luastate, object, point);

        lua_settable(luastate, -3);

    }

}

static void DNP3PushObjects(lua_State *luastate, DNP3ObjectList *objects)

{

    DNP3Object *object = NULL;

    int i = 1;

    TAILQ_FOREACH(object, objects, next) {

        lua_pushinteger(luastate, i++);

        lua_newtable(luastate);

        lua_pushliteral(luastate, "group");

        lua_pushinteger(luastate, object->group);

        lua_settable(luastate, -3);

        lua_pushliteral(luastate, "variation");

        lua_pushinteger(luastate, object->variation);

        lua_settable(luastate, -3);

        lua_pushliteral(luastate, "points");

        lua_newtable(luastate);

        DNP3PushPoints(luastate, object);

        lua_settable(luastate, -3);

        lua_settable(luastate, -3);

    }

}

static void DNP3PushLinkHeader(lua_State *luastate, DNP3LinkHeader *header)

{

    LUA_PUSHT_INT(luastate, "len", header->len);

    LUA_PUSHT_INT(luastate, "control", header->control);

    LUA_PUSHT_INT(luastate, "dst", header->dst);

    LUA_PUSHT_INT(luastate, "src", header->src);

    LUA_PUSHT_INT(luastate, "crc", header->crc);

}

static void DNP3PushApplicationHeader(lua_State *luastate,

    DNP3ApplicationHeader *header)

{

    LUA_PUSHT_INT(luastate, "control", header->control);

    LUA_PUSHT_INT(luastate, "function_code", header->function_code);

}

static void DNP3PushRequest(lua_State *luastate, DNP3Transaction *tx)

{

    /* Link header. */

    lua_pushliteral(luastate, "link_header");

    lua_newtable(luastate);

    DNP3PushLinkHeader(luastate, &tx->lh);

    lua_settable(luastate, -3);

    /* Transport header. */

    LUA_PUSHT_INT(luastate, "transport_header", tx->th);

    /* Application header. */

    lua_pushliteral(luastate, "application_header");

    lua_newtable(luastate);

    DNP3PushApplicationHeader(luastate, &tx->ah);

    lua_settable(luastate, -3);

    lua_pushliteral(luastate, "objects");

    lua_newtable(luastate);

    DNP3PushObjects(luastate, &tx->objects);

    lua_settable(luastate, -3);

}

static void DNP3PushResponse(lua_State *luastate, DNP3Transaction *tx)

{

    /* Link header. */

    lua_pushliteral(luastate, "link_header");

    lua_newtable(luastate);

    DNP3PushLinkHeader(luastate, &tx->lh);

    lua_settable(luastate, -3);

    /* Transport header. */

    LUA_PUSHT_INT(luastate, "transport_header", tx->th);

    /* Application header. */

    lua_pushliteral(luastate, "application_header");

    lua_newtable(luastate);

    DNP3PushApplicationHeader(luastate, &tx->ah);

    lua_settable(luastate, -3);

    /* Internal indicators. */

    LUA_PUSHT_INT(luastate, "indicators", tx->iin.iin1 << 8 | tx->iin.iin2);

    lua_pushliteral(luastate, "objects");

    lua_newtable(luastate);

    DNP3PushObjects(luastate, &tx->objects);

    lua_settable(luastate, -3);

}

static int DNP3GetTx(lua_State *luastate)

{

    if (!LuaStateNeedProto(luastate, ALPROTO_DNP3)) {

        return LuaCallbackError(luastate, "error: protocol not dnp3");

    }

    DNP3Transaction *tx = LuaStateGetTX(luastate);

    if (tx == NULL) {

        return LuaCallbackError(luastate, "error: no tx");

    }

    lua_newtable(luastate);

    lua_pushliteral(luastate, "tx_num");

    lua_pushinteger(luastate, tx->tx_num);

    lua_settable(luastate, -3);

    SCLuaPushTableBoolean(luastate, "is_request", tx->is_request);

    if (tx->is_request) {

        lua_pushliteral(luastate, "request");

        lua_newtable(luastate);

        SCLuaPushTableBoolean(luastate, "done", tx->done);

        SCLuaPushTableBoolean(luastate, "complete", tx->complete);

        DNP3PushRequest(luastate, tx);

        lua_settable(luastate, -3);

    } else {

        lua_pushliteral(luastate, "response");

        lua_newtable(luastate);

        SCLuaPushTableBoolean(luastate, "done", tx->done);

        SCLuaPushTableBoolean(luastate, "complete", tx->complete);

        DNP3PushResponse(luastate, tx);

        lua_settable(luastate, -3);

    }

    return 1;

}

static const struct luaL_Reg dnp3lib[] = {

    // clang-format off

    { "get_tx", DNP3GetTx, },

    { NULL, NULL, }

    // clang-format on

};

int SCLuaLoadDnp3Lib(lua_State *L)

{

    luaL_newlib(L, dnp3lib);

    return 1;

}