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-rw-r--r--src/server/binding.rs150
-rw-r--r--src/server/mod.rs3
-rw-r--r--src/server/resolver.rs165
-rw-r--r--src/server/server.rs73
4 files changed, 0 insertions, 391 deletions
diff --git a/src/server/binding.rs b/src/server/binding.rs
deleted file mode 100644
index 1c69651..0000000
--- a/src/server/binding.rs
+++ /dev/null
@@ -1,150 +0,0 @@
-use std::{
- net::{IpAddr, SocketAddr},
- sync::Arc,
-};
-
-use crate::packet::{buffer::PacketBuffer, Packet, Result};
-use tokio::{
- io::{AsyncReadExt, AsyncWriteExt},
- net::{TcpListener, TcpStream, UdpSocket},
-};
-use tracing::trace;
-
-pub enum Binding {
- UDP(Arc<UdpSocket>),
- TCP(TcpListener),
-}
-
-impl Binding {
- pub async fn udp(addr: SocketAddr) -> Result<Self> {
- let socket = UdpSocket::bind(addr).await?;
- Ok(Self::UDP(Arc::new(socket)))
- }
-
- pub async fn tcp(addr: SocketAddr) -> Result<Self> {
- let socket = TcpListener::bind(addr).await?;
- Ok(Self::TCP(socket))
- }
-
- pub fn name(&self) -> &str {
- match self {
- Binding::UDP(_) => "UDP",
- Binding::TCP(_) => "TCP",
- }
- }
-
- pub async fn connect(&mut self) -> Result<Connection> {
- match self {
- Self::UDP(socket) => {
- let mut buf = [0; 512];
- let (_, addr) = socket.recv_from(&mut buf).await?;
- Ok(Connection::UDP(socket.clone(), addr, buf))
- }
- Self::TCP(socket) => {
- let (stream, _) = socket.accept().await?;
- Ok(Connection::TCP(stream))
- }
- }
- }
-}
-
-pub enum Connection {
- UDP(Arc<UdpSocket>, SocketAddr, [u8; 512]),
- TCP(TcpStream),
-}
-
-impl Connection {
- pub async fn read_packet(&mut self) -> Result<Packet> {
- let data = self.read().await?;
- let mut packet_buffer = PacketBuffer::new(data);
-
- let packet = Packet::from_buffer(&mut packet_buffer)?;
- Ok(packet)
- }
-
- pub async fn write_packet(self, mut packet: Packet) -> Result<()> {
- let mut packet_buffer = PacketBuffer::new(Vec::new());
- packet.write(&mut packet_buffer)?;
-
- self.write(packet_buffer.buf).await?;
- Ok(())
- }
-
- pub async fn request_packet(&self, mut packet: Packet, dest: (IpAddr, u16)) -> Result<Packet> {
- let mut packet_buffer = PacketBuffer::new(Vec::new());
- packet.write(&mut packet_buffer)?;
-
- let data = self.request(packet_buffer.buf, dest).await?;
- let mut packet_buffer = PacketBuffer::new(data);
-
- let packet = Packet::from_buffer(&mut packet_buffer)?;
- Ok(packet)
- }
-
- async fn read(&mut self) -> Result<Vec<u8>> {
- trace!("Reading DNS packet");
- match self {
- Self::UDP(_, _, src) => Ok(Vec::from(*src)),
- Self::TCP(stream) => {
- let size = stream.read_u16().await?;
- let mut buf = Vec::with_capacity(size as usize);
- stream.read_buf(&mut buf).await?;
- Ok(buf)
- }
- }
- }
-
- async fn write(self, mut buf: Vec<u8>) -> Result<()> {
- trace!("Returning DNS packet");
- match self {
- Self::UDP(socket, addr, _) => {
- if buf.len() > 512 {
- buf[2] = buf[2] | 0x03;
- socket.send_to(&buf[0..512], addr).await?;
- } else {
- socket.send_to(&buf, addr).await?;
- }
- Ok(())
- }
- Self::TCP(mut stream) => {
- stream.write_u16(buf.len() as u16).await?;
- stream.write(&buf[0..buf.len()]).await?;
- Ok(())
- }
- }
- }
-
- async fn request(&self, buf: Vec<u8>, dest: (IpAddr, u16)) -> Result<Vec<u8>> {
- match self {
- Self::UDP(_socket, _addr, _src) => {
- let local_addr = "[::]:0".parse::<SocketAddr>()?;
- let socket = UdpSocket::bind(local_addr).await?;
- socket.send_to(&buf, dest).await?;
-
- let mut buf = [0; 512];
- socket.recv_from(&mut buf).await?;
-
- Ok(Vec::from(buf))
- }
- Self::TCP(_stream) => {
- let mut stream = TcpStream::connect(dest).await?;
- stream.write_u16((buf.len()) as u16).await?;
- stream.write_all(&buf[0..buf.len()]).await?;
-
- stream.readable().await?;
- let size = stream.read_u16().await?;
- let mut buf = Vec::with_capacity(size as usize);
- stream.read_buf(&mut buf).await?;
-
- Ok(buf)
- }
- }
- }
-
- // fn pb(buf: &[u8]) {
- // for i in 0..buf.len() {
- // print!("{:02X?} ", buf[i]);
- // }
- // println!("");
- // }
-}
diff --git a/src/server/mod.rs b/src/server/mod.rs
deleted file mode 100644
index 25076ef..0000000
--- a/src/server/mod.rs
+++ /dev/null
@@ -1,3 +0,0 @@
-mod binding;
-mod resolver;
-pub mod server;
diff --git a/src/server/resolver.rs b/src/server/resolver.rs
deleted file mode 100644
index 464620c..0000000
--- a/src/server/resolver.rs
+++ /dev/null
@@ -1,165 +0,0 @@
-use super::binding::Connection;
-use crate::{
- config::Config,
- packet::{
- query::QueryType, question::DnsQuestion, result::ResultCode, Packet,
- Result,
- }, get_time,
-};
-use async_recursion::async_recursion;
-use moka::future::Cache;
-use std::{net::IpAddr, sync::Arc, time::Duration};
-use tracing::{error, trace};
-
-pub struct Resolver {
- request_id: u16,
- connection: Connection,
- config: Arc<Config>,
- cache: Cache<DnsQuestion, (Packet, u64)>,
-}
-
-impl Resolver {
- pub fn new(
- request_id: u16,
- connection: Connection,
- config: Arc<Config>,
- cache: Cache<DnsQuestion, (Packet, u64)>,
- ) -> Self {
- Self {
- request_id,
- connection,
- config,
- cache,
- }
- }
-
- async fn lookup_cache(&mut self, qname: &str, qtype: QueryType) -> Option<Packet> {
- let question = DnsQuestion::new(qname.to_string(), qtype);
- let Some((packet, date)) = self.cache.get(&question) else {
- return None
- };
-
- let now = get_time();
- let diff = Duration::from_millis(now - date).as_secs() as u32;
-
- for answer in &packet.answers {
- let ttl = answer.get_ttl();
- if diff > ttl {
- self.cache.invalidate(&question).await;
- return None
- }
- }
-
- trace!("Found cached value for {qtype:?} {qname}");
-
- Some(packet)
- }
-
- async fn lookup(&mut self, qname: &str, qtype: QueryType, server: (IpAddr, u16)) -> Packet {
- let mut packet = Packet::new();
-
- packet.header.id = self.request_id;
- packet.header.questions = 1;
- packet.header.recursion_desired = true;
- packet
- .questions
- .push(DnsQuestion::new(qname.to_string(), qtype));
-
- let packet = match self.connection.request_packet(packet, server).await {
- Ok(packet) => packet,
- Err(e) => {
- error!("Failed to complete nameserver request: {e}");
- let mut packet = Packet::new();
- packet.header.rescode = ResultCode::SERVFAIL;
- packet
- }
- };
-
- packet
- }
-
- #[async_recursion]
- async fn recursive_lookup(&mut self, qname: &str, qtype: QueryType) -> Packet {
- let question = DnsQuestion::new(qname.to_string(), qtype);
- let mut ns = self.config.get_fallback_ns().clone();
-
- if let Some(packet) = self.lookup_cache(qname, qtype).await { return packet }
-
- loop {
- trace!("Attempting lookup of {qtype:?} {qname} with ns {ns}");
-
- let ns_copy = ns;
-
- let server = (ns_copy, 53);
- let response = self.lookup(qname, qtype, server).await;
-
- if !response.answers.is_empty() && response.header.rescode == ResultCode::NOERROR {
- self.cache.insert(question, (response.clone(), get_time())).await;
- return response;
- }
-
- if response.header.rescode == ResultCode::NXDOMAIN {
- self.cache.insert(question, (response.clone(), get_time())).await;
- return response;
- }
-
- if let Some(new_ns) = response.get_resolved_ns(qname) {
- ns = new_ns;
- continue;
- }
-
- let new_ns_name = match response.get_unresolved_ns(qname) {
- Some(x) => x,
- None => {
- self.cache.insert(question, (response.clone(), get_time())).await;
- return response
- },
- };
-
- let recursive_response = self.recursive_lookup(new_ns_name, QueryType::A).await;
-
- if let Some(new_ns) = recursive_response.get_random_a() {
- ns = new_ns;
- } else {
- self.cache.insert(question, (response.clone(), get_time())).await;
- return response;
- }
- }
- }
-
- pub async fn handle_query(mut self) -> Result<()> {
- let mut request = self.connection.read_packet().await?;
-
- let mut packet = Packet::new();
- packet.header.id = request.header.id;
- packet.header.recursion_desired = true;
- packet.header.recursion_available = true;
- packet.header.response = true;
-
- if let Some(question) = request.questions.pop() {
- trace!("Received query: {question:?}");
-
- let result = self.recursive_lookup(&question.name, question.qtype).await;
- packet.questions.push(question.clone());
- packet.header.rescode = result.header.rescode;
-
- for rec in result.answers {
- trace!("Answer: {rec:?}");
- packet.answers.push(rec);
- }
- for rec in result.authorities {
- trace!("Authority: {rec:?}");
- packet.authorities.push(rec);
- }
- for rec in result.resources {
- trace!("Resource: {rec:?}");
- packet.resources.push(rec);
- }
- } else {
- packet.header.rescode = ResultCode::FORMERR;
- }
-
- self.connection.write_packet(packet).await?;
- Ok(())
- }
-}
diff --git a/src/server/server.rs b/src/server/server.rs
deleted file mode 100644
index e006bb1..0000000
--- a/src/server/server.rs
+++ /dev/null
@@ -1,73 +0,0 @@
-use moka::future::Cache;
-use std::net::SocketAddr;
-use std::sync::Arc;
-use std::time::Duration;
-use tokio::task::JoinHandle;
-use tracing::{error, info};
-
-use crate::config::Config;
-use crate::packet::question::DnsQuestion;
-use crate::packet::{Result, Packet};
-
-use super::binding::Binding;
-use super::resolver::Resolver;
-
-pub struct Server {
- addr: SocketAddr,
- config: Arc<Config>,
- cache: Cache<DnsQuestion, (Packet, u64)>,
-}
-
-impl Server {
- pub async fn new(config: Config) -> Result<Self> {
- let addr = format!("[::]:{}", config.get_port()).parse::<SocketAddr>()?;
- let cache = Cache::builder()
- .time_to_live(Duration::from_secs(60 * 60))
- .max_capacity(1_000)
- .build();
- Ok(Self {
- addr,
- config: Arc::new(config),
- cache,
- })
- }
-
- pub async fn run(&self) -> Result<()> {
- let tcp = Binding::tcp(self.addr).await?;
- let tcp_handle = self.listen(tcp);
-
- let udp = Binding::udp(self.addr).await?;
- let udp_handle = self.listen(udp);
-
- info!("Fallback DNS Server is set to: {:?}", self.config.get_fallback_ns());
- info!("Listening for TCP and UDP traffic on [::]:{}", self.config.get_port());
-
- tokio::join!(tcp_handle)
- .0
- .expect("Failed to join tcp thread");
- tokio::join!(udp_handle)
- .0
- .expect("Failed to join udp thread");
- Ok(())
- }
-
- fn listen(&self, mut binding: Binding) -> JoinHandle<()> {
- let config = self.config.clone();
- let cache = self.cache.clone();
- tokio::spawn(async move {
- let mut id = 0;
- loop {
- let Ok(connection) = binding.connect().await else { continue };
- info!("Received request on {}", binding.name());
-
- let resolver = Resolver::new(id, connection, config.clone(), cache.clone());
-
- if let Err(err) = resolver.handle_query().await {
- error!("{} request {} failed: {:?}", binding.name(), id, err);
- };
-
- id += 1;
- }
- })
- }
-}