0.4.0: XOR encryption + memory optimization

- Optional XOR encryption is now available in lonelyradio and monolib
- lonelyradio was optimized to use less TCP calls and less memory copies
- New program: monoloader - music downloader for lonelyradio
- New monolib function - get_track() for downloading track (as samples),
  not playing
- lonelyradio and monolib are using extensible Writer and Reader enums
  to provide ability to use lonelyradio with different transport
  protocols or encryption
- Add lonelyradio_types crate to share types

Signed-off-by: Ivan Bushchik <ivabus@ivabus.dev>

Cargo.toml

@@ -1,10 +1,16 @@
 [workspace]
-members = ["monoclient", "monolib"]
+members = [
+    "lonelyradio_types",
+    "monoclient",
+    "monolib",
+    "monoloader",
+    "platform/gtk",
+]
 
 [package]
 name = "lonelyradio"
 description = "TCP radio for lonely ones"
-version = "0.3.0"
+version = "0.4.0"
 edition = "2021"
 license = "MIT"
 authors = ["Ivan Bushchik <ivabus@ivabus.dev>"]
@@ -36,6 +42,8 @@ async-stream = "0.3.5"
 tokio-stream = { version = "0.1.15", features = ["sync"] }
 futures-util = "0.3.30"
 samplerate = "0.2.4"
+lonelyradio_types = { path = "./lonelyradio_types" }
+once_cell = "1.19.0"
 
 [profile.release]
 opt-level = 3

README.md

@@ -21,11 +21,13 @@ cargo build -r
 ## Run
 
 ```
-lonelyradio [-a <ADDRESS:PORT>] <MUSIC_FOLDER> [-p] [-w]
+lonelyradio <MUSIC_FOLDER> [-a <ADDRESS:PORT>] [-p] [-w] [-m|--max-samplerate M]
 ```
 
 All files (recursively) will be shuffled and played back. Public log will be displayed to stdout, private to stderr.
 
+`-m|--max-samplerate M` will resample tracks which samplerate exceeds M to M
+
 ### Clients
 
 [monoclient](./monoclient) is a recommended CLI client for lonelyradio that uses [monolib](./monolib)

lonelyradio_types/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "lonelyradio_types"
+version = "0.4.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+serde = { version = "1.0.197", features = ["derive"] }

lonelyradio_types/src/lib.rs

@@ -0,0 +1,29 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Deserialize, Serialize, Clone, Debug, PartialEq)]
+pub enum Message {
+	T(TrackMetadata),
+	F(FragmentMetadata),
+}
+
+#[derive(Deserialize, Serialize, Clone, Debug, PartialEq)]
+pub struct TrackMetadata {
+	pub track_length_secs: u64,
+	pub track_length_frac: f32,
+	pub channels: u16,
+	pub sample_rate: u32,
+	pub title: String,
+	pub album: String,
+	pub artist: String,
+}
+
+#[derive(Deserialize, Serialize, Clone, Debug, PartialEq)]
+pub struct FragmentMetadata {
+	// In samples
+	pub length: u64,
+}
+
+#[derive(Deserialize, Serialize, Clone, Debug, PartialEq)]
+pub struct SessionSettings {
+	pub gzip: bool,
+}

monoclient/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "monoclient"
-version = "0.3.0"
+version = "0.4.0"
 edition = "2021"
 license = "MIT"
 

monoclient/src/main.rs

@@ -3,6 +3,7 @@ use crossterm::cursor::MoveToColumn;
 use crossterm::style::Print;
 use crossterm::terminal::{Clear, ClearType};
 use std::io::{stdout, IsTerminal};
+use std::path::PathBuf;
 use std::time::{Duration, Instant};
 
 #[derive(Parser)]
@@ -13,12 +14,20 @@ struct Args {
 	/// Do not use backspace control char
 	#[arg(short)]
 	no_backspace: bool,
+
+	#[arg(long)]
+	xor_key_file: Option<PathBuf>,
 }
 
 fn main() {
 	let mut args = Args::parse();
 	args.no_backspace |= !std::io::stdout().is_terminal();
-	std::thread::spawn(move || monolib::run(&args.address));
+	std::thread::spawn(move || {
+		monolib::run(
+			&args.address,
+			args.xor_key_file.map(|key| std::fs::read(key).expect("Failed to read preshared key")),
+		)
+	});
 	while monolib::get_metadata().is_none() {}
 	let mut md = monolib::get_metadata().unwrap();
 	let mut track_start = Instant::now();
@@ -35,9 +44,13 @@ fn main() {
 		))
 	)
 	.unwrap();
+	let mut track_length = md.track_length_secs as f64 + md.track_length_frac as f64;
+	let mut next_md = md.clone();
 	loop {
-		if monolib::get_metadata().unwrap() != md {
-			md = monolib::get_metadata().unwrap();
+		if monolib::get_metadata().unwrap() != md
+			&& track_length <= (Instant::now() - track_start).as_secs_f64()
+		{
+			md = next_md.clone();
 			crossterm::execute!(stdout(), Clear(ClearType::CurrentLine), MoveToColumn(0)).unwrap();
 			print!(
 				"Playing: {} - {} - {} (0:00 / {}:{:02})",
@@ -49,6 +62,9 @@ fn main() {
 			);
 			track_start = Instant::now();
 			seconds_past = 0;
+			track_length = md.track_length_secs as f64 + md.track_length_frac as f64
+		} else if next_md == md {
+			next_md = monolib::get_metadata().unwrap();
 		}
 		if (Instant::now() - track_start).as_secs() > seconds_past && !args.no_backspace {
 			seconds_past = (Instant::now() - track_start).as_secs();

monolib/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "monolib"
-version = "0.3.0"
+version = "0.4.0"
 edition = "2021"
 license = "MIT"
 description = "A library implementing the lonely radio audio streaming protocol"
@@ -15,4 +15,4 @@ crate-type = ["staticlib", "cdylib", "rlib"]
 rodio = { version = "0.17.3", default-features = false }
 byteorder = "1.5.0"
 rmp-serde = "1.1.2"
-serde = { version = "1.0.197", features = ["derive"] }
+lonelyradio_types = { path = "../lonelyradio_types" }

monolib/src/c.rs

@@ -7,10 +7,13 @@ use std::ffi::{CStr, CString};
 #[allow(clippy::not_unsafe_ptr_arg_deref)]
 pub extern "C" fn c_start(server: *const c_char) {
 	let serv = unsafe { CStr::from_ptr(server) };
-	run(match serv.to_str() {
+	run(
+		match serv.to_str() {
 			Ok(s) => s,
 			_ => "",
-	})
+		},
+		None,
+	)
 }
 
 #[no_mangle]
@@ -69,7 +72,7 @@ pub extern "C" fn c_get_metadata_title() -> *mut c_char {
 pub extern "C" fn c_get_metadata_length() -> *mut c_float {
 	let md = MD.read().unwrap();
 	match md.as_ref() {
-		Some(md) => &mut (md.length as c_float / md.sample_rate as c_float),
+		Some(md) => &mut (md.track_length_secs as c_float + md.track_length_frac as c_float),
 		None => &mut 0.0,
 	}
 }

monolib/src/lib.rs

@@ -16,20 +16,21 @@
 
 /// Functions, providing C-like API
 pub mod c;
+mod reader;
 
-use byteorder::ByteOrder;
+use byteorder::{LittleEndian, ReadBytesExt};
+use lonelyradio_types::{Message, TrackMetadata};
 use rodio::buffer::SamplesBuffer;
 use rodio::{OutputStream, Sink};
-use serde::Deserialize;
-use std::io::Read;
+use std::io::BufReader;
 use std::net::TcpStream;
 use std::sync::RwLock;
 use std::time::Instant;
 
-const CACHE_SIZE: usize = 500;
+const CACHE_SIZE: usize = 32;
 
 static SINK: RwLock<Option<Sink>> = RwLock::new(None);
-static MD: RwLock<Option<Metadata>> = RwLock::new(None);
+static MD: RwLock<Option<TrackMetadata>> = RwLock::new(None);
 static STATE: RwLock<State> = RwLock::new(State::NotStarted);
 
 /// Player state
@@ -42,22 +43,6 @@ pub enum State {
 	Paused = 3,
 }
 
-/// Track metadata
-#[derive(Deserialize, Clone, Debug, PartialEq)]
-pub struct Metadata {
-	/// Fragment length
-	pub length: u64,
-	/// Total track length
-	pub track_length_secs: u64,
-	pub track_length_frac: f32,
-	pub channels: u16,
-	// Yep, no more interpolation
-	pub sample_rate: u32,
-	pub title: String,
-	pub album: String,
-	pub artist: String,
-}
-
 /// Play/pauses playback
 pub fn toggle() {
 	let mut state = crate::STATE.write().unwrap();
@@ -81,6 +66,9 @@ pub fn toggle() {
 /// Stops playback
 pub fn stop() {
 	let mut state = STATE.write().unwrap();
+	if *state == State::NotStarted {
+		return;
+	}
 	*state = State::Resetting;
 
 	let sink = SINK.read().unwrap();
@@ -99,7 +87,7 @@ pub fn get_state() -> State {
 	*STATE.read().unwrap()
 }
 
-pub fn get_metadata() -> Option<Metadata> {
+pub fn get_metadata() -> Option<TrackMetadata> {
 	MD.read().unwrap().clone()
 }
 
@@ -130,8 +118,37 @@ fn watching_sleep(dur: f32) -> bool {
 	false
 }
 
+/// Download track as samples
+pub fn get_track(server: &str, xor_key: Option<Vec<u8>>) -> Option<(TrackMetadata, Vec<i16>)> {
+	let mut stream = BufReader::new(match xor_key {
+		Some(k) => reader::Reader::XorEncrypted(TcpStream::connect(server).unwrap(), k, 0),
+		None => reader::Reader::Unencrypted(TcpStream::connect(server).unwrap()),
+	});
+
+	let mut samples = vec![];
+	let mut md: Option<TrackMetadata> = None;
+	loop {
+		let recv_md: Message = rmp_serde::from_read(&mut stream).expect("Failed to parse message");
+		match recv_md {
+			Message::T(tmd) => {
+				if md.is_some() {
+					break;
+				}
+				md = Some(tmd);
+			}
+			Message::F(fmd) => {
+				let mut buf = vec![0; fmd.length as usize];
+				stream.read_i16_into::<LittleEndian>(&mut buf).unwrap();
+				samples.append(&mut buf);
+			}
+		}
+	}
+
+	md.map(|md| (md, samples))
+}
+
 /// Starts playing at "server:port"
-pub fn run(server: &str) {
+pub fn run(server: &str, xor_key: Option<Vec<u8>>) {
 	let mut state = STATE.write().unwrap();
 	if *state == State::Playing || *state == State::Paused {
 		return;
@@ -139,7 +156,11 @@ pub fn run(server: &str) {
 	*state = State::Playing;
 	drop(state);
 
-	let mut stream = TcpStream::connect(server).unwrap();
+	let mut stream = BufReader::new(match xor_key {
+		Some(k) => reader::Reader::XorEncrypted(TcpStream::connect(server).unwrap(), k, 0),
+		None => reader::Reader::Unencrypted(TcpStream::connect(server).unwrap()),
+	});
+
 	let mut sink = SINK.write().unwrap();
 	let (_stream, stream_handle) = OutputStream::try_default().unwrap();
 
@@ -148,16 +169,15 @@ pub fn run(server: &str) {
 	*sink = Some(audio_sink);
 	drop(sink);
 
-	let mut buffer = [0u8; 2];
 	let mut samples = Vec::with_capacity(8192);
 	loop {
-		let recv_md: Metadata =
-			rmp_serde::from_read(&stream).expect("Failed to parse track metadata");
-
+		let recv_md: Message = rmp_serde::from_read(&mut stream).expect("Failed to parse message");
+		match recv_md {
+			Message::T(tmd) => {
 				let mut md = MD.write().unwrap();
-		*md = Some(recv_md.clone());
-		drop(md);
-		for _ in 0..recv_md.length {
+				*md = Some(tmd.clone());
+			}
+			Message::F(fmd) => {
 				while *STATE.read().unwrap() == State::Paused {
 					std::thread::sleep(std::time::Duration::from_secs_f32(0.25))
 				}
@@ -165,17 +185,21 @@ pub fn run(server: &str) {
 					_stop();
 					return;
 				}
-
-			if stream.read_exact(&mut buffer).is_err() {
+				let mut samples_i16 = vec![0; fmd.length as usize];
+				if stream.read_i16_into::<LittleEndian>(&mut samples_i16).is_err() {
 					return;
 				};
-			samples.push(byteorder::LittleEndian::read_i16(&buffer[..2]) as f32 / 32768.0);
-		}
+				samples.append(
+					&mut samples_i16.iter().map(|sample| *sample as f32 / 32767.0).collect(),
+				);
+
 				// Sink's thread is detached from main thread, so we need to synchronize with it
 				// Why we should synchronize with it?
 				// Let's say, that if we don't synchronize with it, we would have
 				// a lot (no upper limit, actualy) of buffered sound, waiting for playing in sink
 				let sink = SINK.read().unwrap();
+				let md = MD.read().unwrap();
+				let md = md.as_ref().unwrap();
 				if let Some(sink) = sink.as_ref() {
 					while sink.len() >= CACHE_SIZE {
 						// Sleeping exactly one buffer and watching for reset signal
@@ -184,20 +208,21 @@ pub fn run(server: &str) {
 								sink.len() as f32 - 2.0
 							} else {
 								0.25
-					} * recv_md.length as f32
-						/ recv_md.sample_rate as f32
-						/ 2.0,
+							} * fmd.length as f32 / md.sample_rate as f32
+								/ 4.0,
 						) {
 							_stop();
 							return;
 						}
 					}
 					sink.append(SamplesBuffer::new(
-				recv_md.channels,
-				recv_md.sample_rate,
+						md.channels,
+						md.sample_rate,
 						samples.as_slice(),
 					));
 					samples.clear();
 				}
 			}
 		}
+	}
+}

monolib/src/reader.rs

@@ -0,0 +1,25 @@
+use std::{io, net::TcpStream};
+
+pub(crate) enum Reader {
+	Unencrypted(TcpStream),
+	XorEncrypted(TcpStream, Vec<u8>, u64),
+}
+
+impl io::Read for Reader {
+	fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+		match self {
+			Self::Unencrypted(s) => s.read(buf),
+			Self::XorEncrypted(s, key, n) => {
+				let out = s.read(buf);
+				if let Ok(i) = &out {
+					for k in buf.iter_mut().take(*i) {
+						*k ^= key[*n as usize];
+						*n += 1;
+						*n %= key.len() as u64;
+					}
+				}
+				out
+			}
+		}
+	}
+}

monoloader/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "monoloader"
+version = "0.4.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+monolib = { path = "../monolib" }
+clap = { version = "4.4.18", features = ["derive"] }
+hound = "3.5.1"

monoloader/src/main.rs

@@ -0,0 +1,38 @@
+use clap::Parser;
+use std::path::PathBuf;
+
+#[derive(Parser)]
+struct Args {
+	/// Remote address
+	address: String,
+
+	#[arg(long)]
+	xor_key_file: Option<PathBuf>,
+}
+
+fn main() {
+	let args = Args::parse();
+	let (md, samples) = monolib::get_track(
+		&args.address,
+		args.xor_key_file.map(|key| std::fs::read(key).expect("Failed to read preshared key")),
+	)
+	.unwrap();
+	println!(
+		"Downloaded: {} - {} - {} ({} MB)",
+		md.artist,
+		md.album,
+		md.title,
+		samples.len() as f32 * 2.0 / 1024.0 / 1024.0
+	);
+	let spec = hound::WavSpec {
+		channels: md.channels,
+		sample_rate: md.sample_rate,
+		bits_per_sample: 16,
+		sample_format: hound::SampleFormat::Int,
+	};
+	let mut writer =
+		hound::WavWriter::create(format!("{} - {}.wav", md.artist, md.title), spec).unwrap();
+	let mut writer_i16 = writer.get_i16_writer(samples.len() as u32);
+	samples.iter().for_each(|s| writer_i16.write_sample(*s));
+	writer_i16.flush().unwrap();
+}

src/decode.rs

@@ -1,6 +1,8 @@
 use std::path::{Path, PathBuf};
 
+use async_stream::stream;
 use clap::Parser;
+use futures_util::Stream;
 use symphonia::core::audio::SampleBuffer;
 use symphonia::core::codecs::CODEC_TYPE_NULL;
 use symphonia::core::io::MediaSourceStream;
@@ -75,7 +77,7 @@ pub async fn get_meta(file_path: &Path) -> (u16, u32, Time) {
 }
 
 /// Getting samples
-pub async fn decode_file(file_path: PathBuf, tx: tokio::sync::mpsc::Sender<Vec<i16>>) {
+pub fn decode_file_stream(file_path: PathBuf) -> impl Stream<Item = Vec<i16>> {
 	let args = Args::parse();
 	let file = Box::new(std::fs::File::open(&file_path).unwrap());
 	let mut hint = Hint::new();
@@ -102,6 +104,7 @@ pub async fn decode_file(file_path: PathBuf, tx: tokio::sync::mpsc::Sender<Vec<i
 		.make(&track.codec_params, &Default::default())
 		.expect("unsupported codec");
 	let track_id = track.id;
+	stream! {
 		loop {
 			let packet = match format.next_packet() {
 				Ok(packet) => packet,
@@ -120,8 +123,9 @@ pub async fn decode_file(file_path: PathBuf, tx: tokio::sync::mpsc::Sender<Vec<i
 							SampleBuffer::<f32>::new(decoded.capacity() as u64, *decoded.spec());
 						byte_buf.copy_interleaved_ref(decoded);
 
-					tx.send(
-						samplerate::convert(
+						// About Samplerate struct:
+						// We are downsampling, not upsampling, so we should be fine
+						yield (samplerate::convert(
 								spec.rate,
 								args.max_samplerate,
 								spec.channels.count(),
@@ -130,16 +134,14 @@ pub async fn decode_file(file_path: PathBuf, tx: tokio::sync::mpsc::Sender<Vec<i
 							)
 							.unwrap()
 							.iter()
-						.map(|x| (*x * 32767.0) as i16)
-						.collect(),
-					)
-					.await
-					.unwrap();
+							.map(|x| (*x * 32768.0) as i16)
+							.collect());
+
 					} else {
 						let mut byte_buf =
 							SampleBuffer::<i16>::new(decoded.capacity() as u64, *decoded.spec());
 						byte_buf.copy_interleaved_ref(decoded);
-					tx.send(byte_buf.samples().to_vec()).await.unwrap();
+						yield (byte_buf.samples().to_vec());
 					}
 					continue;
 				}
@@ -150,3 +152,4 @@ pub async fn decode_file(file_path: PathBuf, tx: tokio::sync::mpsc::Sender<Vec<i
 			}
 		}
 	}
+}

src/main.rs

@@ -1,4 +1,5 @@
 mod decode;
+mod writer;
 
 use std::path::Path;
 use std::path::PathBuf;
@@ -9,16 +10,17 @@ use clap::Parser;
 use futures_util::pin_mut;
 use lofty::Accessor;
 use lofty::TaggedFileExt;
+use lonelyradio_types::{FragmentMetadata, Message, TrackMetadata};
+use once_cell::sync::Lazy;
 use rand::prelude::*;
-use serde::Serialize;
-use tokio::io::AsyncWriteExt;
+use std::io::Write;
 use tokio::net::{TcpListener, TcpStream};
-use tokio::sync::mpsc;
 use tokio_stream::Stream;
 use tokio_stream::StreamExt;
 use walkdir::DirEntry;
+use writer::Writer;
 
-use crate::decode::decode_file;
+use crate::decode::decode_file_stream;
 use crate::decode::get_meta;
 
 #[derive(Parser)]
@@ -35,50 +37,58 @@ struct Args {
 
 	#[arg(short, long, default_value = "96000")]
 	max_samplerate: u32,
+
+	#[arg(long)]
+	xor_key_file: Option<PathBuf>,
 }
 
-#[derive(Serialize, Clone)]
-struct SentMetadata {
-	/// Fragment length
-	length: u64,
-	/// Total track length
-	track_length_secs: u64,
-	track_length_frac: f32,
-	channels: u16,
-	sample_rate: u32,
-	title: String,
-	album: String,
-	artist: String,
+static KEY: Lazy<Option<Arc<Vec<u8>>>> = Lazy::new(|| {
+	let args = Args::parse();
+	if let Some(path) = args.xor_key_file {
+		let key = std::fs::read(path).expect("Failed to read preshared key");
+		Some(Arc::new(key))
+	} else {
+		None
 	}
+});
 
-async fn stream_samples(
+async fn stream_track(
 	samples_stream: impl Stream<Item = Vec<i16>>,
 	war: bool,
-	md: SentMetadata,
-	s: &mut TcpStream,
+	md: TrackMetadata,
+	s: &mut Writer,
 ) -> bool {
 	pin_mut!(samples_stream);
 
-	while let Some(samples) = samples_stream.next().await {
-		let mut md = md.clone();
-		md.length = samples.len() as u64;
-		if s.write_all(rmp_serde::to_vec(&md).unwrap().as_slice()).await.is_err() {
-			return true;
-		}
-		for sample in samples {
-			if s.write_all(
-				&(if war {
-					sample.signum() * 32767
-				} else {
-					sample
-				}
-				.to_le_bytes()),
-			)
-			.await
-			.is_err()
-			{
+	if s.write_all(rmp_serde::to_vec(&Message::T(md)).unwrap().as_slice()).is_err() {
 		return true;
 	};
+
+	while let Some(mut _samples) = samples_stream.next().await {
+		let md = Message::F(FragmentMetadata {
+			length: _samples.len() as u64,
+		});
+		if s.write_all(rmp_serde::to_vec(&md).unwrap().as_slice()).is_err() {
+			return true;
+		}
+
+		if war {
+			_samples.iter_mut().for_each(|sample| {
+				*sample = sample.signum() * 32767;
+			});
+		}
+		// Launching lonelyradio on the router moment
+		if cfg!(target_endian = "big") {
+			_samples.iter_mut().for_each(|sample| {
+				*sample = sample.to_le();
+			});
+		}
+
+		// Sowwy about that
+		let (_, samples, _) = unsafe { _samples.align_to::<u8>() };
+
+		if s.write_all(samples).is_err() {
+			return true;
 		}
 	}
 	false
@@ -117,10 +127,24 @@ fn track_valid(track: &Path) -> bool {
 	true
 }
 
-async fn stream(mut s: TcpStream, tracklist: Arc<Vec<PathBuf>>) {
+async fn stream(s: TcpStream, tracklist: Arc<Vec<PathBuf>>) {
 	let args = Args::parse();
-	s.set_nodelay(true).unwrap();
-
+	let s = s.into_std().unwrap();
+	s.set_nonblocking(false).unwrap();
+	let mut s = if args.xor_key_file.is_some() {
+		Writer::XorEncrypted(
+			s,
+			match &*KEY {
+				Some(a) => a.clone(),
+				_ => {
+					unreachable!()
+				}
+			},
+			0,
+		)
+	} else {
+		Writer::Unencrypted(s)
+	};
 	loop {
 		let track = tracklist.choose(&mut thread_rng()).unwrap().clone();
 
@@ -163,23 +187,16 @@ async fn stream(mut s: TcpStream, tracklist: Arc<Vec<PathBuf>>) {
 			);
 		}
 		let (channels, sample_rate, time) = get_meta(track.as_path()).await;
-		let (tx, mut rx) = mpsc::channel::<Vec<i16>>(8192);
-		tokio::spawn(decode_file(track, tx));
-		let stream = async_stream::stream! {
-			while let Some(item) = rx.recv().await {
-				yield item;
-			}
-		};
-		if stream_samples(
+		let stream = decode_file_stream(track);
+		if stream_track(
 			stream,
 			args.war,
-			SentMetadata {
+			TrackMetadata {
+				track_length_frac: time.frac as f32,
+				track_length_secs: time.seconds,
 				album,
 				artist,
 				title,
-				length: 0,
-				track_length_frac: time.frac as f32,
-				track_length_secs: time.seconds,
 				sample_rate,
 				channels,
 			},

src/writer.rs

@@ -0,0 +1,59 @@
+use std::{
+	borrow::BorrowMut,
+	io,
+	net::{SocketAddr, TcpStream},
+	sync::Arc,
+};
+
+pub(crate) enum Writer {
+	Unencrypted(TcpStream),
+	XorEncrypted(TcpStream, Arc<Vec<u8>>, u64),
+}
+
+impl io::Write for Writer {
+	fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+		match self {
+			Self::Unencrypted(s) => s.write(buf),
+			Self::XorEncrypted(s, key, n) => {
+				for mut k in buf.iter().copied() {
+					k ^= key[*n as usize];
+					*n += 1;
+					*n %= key.len() as u64;
+					s.write_all(&[k])?;
+				}
+				Ok(buf.len())
+			}
+		}
+	}
+	fn write_all(&mut self, buf: &[u8]) -> io::Result<()> {
+		match self {
+			Self::Unencrypted(s) => s.write_all(buf),
+			Self::XorEncrypted(s, key, n) => s.write_all(
+				&buf.iter()
+					.borrow_mut()
+					.copied()
+					.map(|mut k| {
+						k ^= key[*n as usize];
+						*n += 1;
+						*n %= key.len() as u64;
+						k
+					})
+					// I don't like it
+					.collect::<Vec<u8>>(),
+			),
+		}
+	}
+	fn flush(&mut self) -> io::Result<()> {
+		match self {
+			Self::XorEncrypted(s, _, _) | Self::Unencrypted(s) => s.flush(),
+		}
+	}
+}
+
+impl Writer {
+	pub fn peer_addr(&self) -> io::Result<SocketAddr> {
+		match self {
+			Self::XorEncrypted(s, _, _) | Self::Unencrypted(s) => s.peer_addr(),
+		}
+	}
+}