/* Copyright (C) 2017 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.

 */

use std::os::raw::c_int;

use crate::dns::dns::*;

use crate::dns::log::*;

use crate::lua::*;

#[no_mangle]

pub extern "C" fn SCDnsLuaGetTxId(clua: &mut CLuaState, tx: &mut DNSTransaction) -> c_int {

    let lua = LuaState { lua: clua };

    lua.pushinteger(tx.tx_id() as i64);

    return 1;

}

#[no_mangle]

pub extern "C" fn SCDnsLuaGetRrname(clua: &mut CLuaState, tx: &mut DNSTransaction) -> c_int {

    let lua = LuaState { lua: clua };

    if let Some(request) = &tx.request {

        if let Some(query) = request.queries.first() {

            lua.pushstring(&String::from_utf8_lossy(&query.name.value));

            return 1;

        }

    } else if let Some(response) = &tx.response {

        if let Some(query) = response.queries.first() {

            lua.pushstring(&String::from_utf8_lossy(&query.name.value));

            return 1;

        }

    }

    return 0;

}

#[no_mangle]

pub extern "C" fn SCDnsLuaGetRcode(clua: &mut CLuaState, tx: &mut DNSTransaction) -> c_int {

    let lua = LuaState { lua: clua };

    lua.pushinteger(tx.rcode() as i64);

    return 1;

}

#[no_mangle]

pub extern "C" fn SCDnsLuaGetRcodeString(clua: &mut CLuaState, tx: &mut DNSTransaction) -> c_int {

    let lua = LuaState { lua: clua };

    lua.pushstring(&dns_rcode_string(tx.rcode()));

    return 1;

}

#[no_mangle]

pub extern "C" fn SCDnsLuaGetQueryTable(clua: &mut CLuaState, tx: &mut DNSTransaction) -> c_int {

    let lua = LuaState { lua: clua };

    let mut i: i64 = 0;

    // Create table now to be consistent with C that always returns

    // table even in the absence of any authorities.

    lua.newtable();

    // We first look in the request for queries. However, if there is

    // no request, check the response for queries.

    if let Some(request) = &tx.request {

        for query in &request.queries {

            lua.pushinteger(i);

            i += 1;

            lua.newtable();

            lua.pushstring("type");

            lua.pushstring(&dns_rrtype_string(query.rrtype));

            lua.settable(-3);

            lua.pushstring("rrname");

            lua.pushstring(&String::from_utf8_lossy(&query.name.value));

            lua.settable(-3);

            lua.settable(-3);

        }

    } else if let Some(response) = &tx.response {

        for query in &response.queries {

            lua.pushinteger(i);

            i += 1;

            lua.newtable();

            lua.pushstring("type");

            lua.pushstring(&dns_rrtype_string(query.rrtype));

            lua.settable(-3);

            lua.pushstring("rrname");

            lua.pushstring(&String::from_utf8_lossy(&query.name.value));

            lua.settable(-3);

            lua.settable(-3);

        }

    }

    // Again, always return 1 to be consistent with C, even if the

    // table is empty.

    return 1;

}

#[no_mangle]

pub extern "C" fn SCDnsLuaGetAnswerTable(clua: &mut CLuaState, tx: &mut DNSTransaction) -> c_int {

    let lua = LuaState { lua: clua };

    let mut i: i64 = 0;

    // Create table now to be consistent with C that always returns

    // table even in the absence of any authorities.

    lua.newtable();

    if let Some(response) = &tx.response {

        for answer in &response.answers {

            lua.pushinteger(i);

            i += 1;

            lua.newtable();

            lua.pushstring("type");

            lua.pushstring(&dns_rrtype_string(answer.rrtype));

            lua.settable(-3);

            lua.pushstring("ttl");

            lua.pushinteger(answer.ttl as i64);

            lua.settable(-3);

            lua.pushstring("rrname");

            lua.pushstring(&String::from_utf8_lossy(&answer.name.value));

            lua.settable(-3);

            // All rdata types are pushed to "addr" for backwards compatibility

            match &answer.data {

                DNSRData::A(ref bytes) | DNSRData::AAAA(ref bytes) => {

                    if !bytes.is_empty() {

                        lua.pushstring("addr");

                        lua.pushstring(&dns_print_addr(bytes));

                        lua.settable(-3);

                    }

                }

                DNSRData::CNAME(name)

                | DNSRData::MX(name)

                | DNSRData::NS(name)

                | DNSRData::PTR(name) => {

                    if !name.value.is_empty() {

                        lua.pushstring("addr");

                        lua.pushstring(&String::from_utf8_lossy(&name.value));

                        lua.settable(-3);

                    }

                }

                DNSRData::TXT(ref txt) => {

                    if !txt.is_empty() {

                        lua.pushstring("addr");

                        let combined = txt

                            .iter()

                            .map(|s| String::from_utf8_lossy(s))

                            .collect::<Vec<_>>()

                            .join(" ");

                        lua.pushstring(&combined);

                        lua.settable(-3);

                    }

                }

                DNSRData::NULL(ref bytes)

                | DNSRData::Unknown(ref bytes) => {

                    if !bytes.is_empty() {

                        lua.pushstring("addr");

                        lua.pushstring(&String::from_utf8_lossy(bytes));

                        lua.settable(-3);

                    }

                }

                DNSRData::SOA(ref soa) => {

                    if !soa.mname.value.is_empty() {

                        lua.pushstring("addr");

                        lua.pushstring(&String::from_utf8_lossy(&soa.mname.value));

                        lua.settable(-3);

                    }

                }

                DNSRData::SSHFP(ref sshfp) => {

                    lua.pushstring("addr");

                    lua.pushstring(&String::from_utf8_lossy(&sshfp.fingerprint));

                    lua.settable(-3);

                }

                DNSRData::SRV(ref srv) => {

                    lua.pushstring("addr");

                    lua.pushstring(&String::from_utf8_lossy(&srv.target.value));

                    lua.settable(-3);

                }

                DNSRData::OPT(ref opt) => {

                    if !opt.is_empty() {

                        lua.pushstring("addr");

                        for option in opt.iter() {

                            lua.pushstring(&String::from_utf8_lossy(&option.code.to_be_bytes()));

                            lua.pushstring(&String::from_utf8_lossy(&option.data));

                        }

                        lua.settable(-3);

                    }

                }

            }

            lua.settable(-3);

        }

    }

    // Again, always return 1 to be consistent with C, even if the

    // table is empty.

    return 1;

}

#[no_mangle]

pub extern "C" fn SCDnsLuaGetAuthorityTable(

    clua: &mut CLuaState, tx: &mut DNSTransaction,

) -> c_int {

    let lua = LuaState { lua: clua };

    let mut i: i64 = 0;

    // Create table now to be consistent with C that always returns

    // table even in the absence of any authorities.

    lua.newtable();

    if let Some(response) = &tx.response {

        for answer in &response.authorities {

            lua.pushinteger(i);

            i += 1;

            lua.newtable();

            lua.pushstring("type");

            lua.pushstring(&dns_rrtype_string(answer.rrtype));

            lua.settable(-3);

            lua.pushstring("ttl");

            lua.pushinteger(answer.ttl as i64);

            lua.settable(-3);

            lua.pushstring("rrname");

            lua.pushstring(&String::from_utf8_lossy(&answer.name.value));

            lua.settable(-3);

            lua.settable(-3);

        }

    }

    // Again, always return 1 to be consistent with C, even if the

    // table is empty.

    return 1;

}