change server ID from `u8` to a string

prototypes/quic_demo/README.md

@@ -24,6 +24,8 @@ The end-to-end testing above is the happy path. Try these sadder cases:
 
 # Network protocol
 
+(This section is out of date. It describes an older version)
+
 For the prototype, all control messages are fixed 4-byte messages at the
 start of bidirectional streams.
 

prototypes/quic_demo/src/bin/quic_demo_client.rs

@@ -11,7 +11,7 @@ struct Opt {
 	#[structopt (long)]
 	local_tcp_port: Option <u16>,
 	#[structopt (long)]
-	client_id: Option <String>,
+	client_id: Option <PeerId>,
 	#[structopt (long)]
 	server_id: Option <PeerId>,
 }
@@ -36,7 +36,7 @@ async fn main () -> anyhow::Result <()> {
 		..
 	} = protocol::p2_connect_to_p3 (&endpoint, &relay_addr, &client_id).await?;
 	
-	let server_id = opt.server_id.unwrap_or (43);
+	let server_id = opt.server_id.unwrap_or_else (|| "bogus_server".to_string ());
 	
 	let listener = TcpListener::bind (("127.0.0.1", local_tcp_port)).await?;
 	
@@ -45,13 +45,14 @@ async fn main () -> anyhow::Result <()> {
 	loop {
 		let (tcp_socket, _) = listener.accept ().await?;
 		let connection = connection.clone ();
+		let server_id = server_id.clone ();
 		
 		tokio::spawn (async move {
 			let (local_recv, local_send) = tcp_socket.into_split ();
 			
 			debug! ("Starting PTTH connection");
 			
-			let (relay_send, relay_recv) = protocol::p2_connect_to_p5 (&connection, server_id).await?;
+			let (relay_send, relay_recv) = protocol::p2_connect_to_p5 (&connection, &server_id).await?;
 			
 			trace! ("Relaying bytes...");
 			

prototypes/quic_demo/src/bin/quic_demo_end_server.rs

@@ -27,12 +27,12 @@ async fn main () -> anyhow::Result <()> {
 	
 	trace! ("Connecting to relay server");
 	
-	let server_id = opt.server_id.unwrap_or (43);
+	let server_id = opt.server_id.unwrap_or_else (|| "bogus_server".to_string ());
 	
 	let quinn::NewConnection {
 		mut bi_streams,
 		..
-	} = protocol::p4_connect_to_p3 (&endpoint, &relay_addr, server_id).await?;
+	} = protocol::p4_connect_to_p3 (&endpoint, &relay_addr, &server_id).await?;
 	
 	trace! ("Accepting bi streams from P3");
 	

prototypes/quic_demo/src/bin/quic_demo_relay_server.rs

@@ -277,11 +277,12 @@ async fn handle_p4_connection (
 	
 	{
 		let mut p4_server_proxies = relay_state.p4_server_proxies.lock ().await;
-		p4_server_proxies.insert (server_id, p4_state);
+		p4_server_proxies.insert (server_id.clone (), p4_state);
 	}
 	
 	while let Some (req) = rx.recv ().await {
 		let connection = connection.clone ();
+		let server_id = server_id.clone ();
 		
 		tokio::spawn (async move {
 			let RequestP2ToP4 {

prototypes/quic_demo/src/protocol.rs

@@ -10,7 +10,7 @@ use quinn::{
 
 use crate::prelude::*;
 
-pub type PeerId = u8;
+pub type PeerId = String;
 const MAX_ID_LENGTH: usize = 128;
 
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
@@ -50,7 +50,7 @@ pub async fn p2_connect_to_p3 (
 
 pub async fn p2_connect_to_p5 (
 	connection: &quinn::Connection,
-	server_id: PeerId,
+	server_id: &str,
 ) -> Result <(SendStream, RecvStream)>
 {
 	let (mut send, mut recv) = connection.open_bi ().await?;
@@ -59,7 +59,8 @@ pub async fn p2_connect_to_p5 (
 	
 	let cmd_type = Command::CONNECT_P2_TO_P4.0;
 	
-	send.write_all (&[cmd_type, server_id, 0, 0]).await?;
+	send.write_all (&[cmd_type, 0, 0, 0]).await?;
+	send_lv_string (&mut send, &server_id).await?;
 	
 	expect_exact_response (&mut recv, [Command::OKAY.0, cmd_type, 0, 0]).await
 	.context ("P2 didn't get OK response when asking P3 to connect P2 to P4")?;
@@ -82,7 +83,7 @@ pub enum P3Peer {
 }
 
 pub struct P2ClientProxy {
-	pub id: String,
+	pub id: PeerId,
 }
 
 pub struct P4ServerProxy {
@@ -101,14 +102,13 @@ pub async fn p3_accept_peer (
 	Ok (match command {
 		Command::CONNECT_P2_TO_P3 => {
 			let id = recv_lv_string (recv, MAX_ID_LENGTH).await?;
-			
 			debug! ("Client-side proxy (P2) connected, ID {}", id);
 			P3Peer::P2ClientProxy (P2ClientProxy {
 				id,
 			})
 		},
 		Command::CONNECT_P4_TO_P3 => {
-			let id = buf [1];
+			let id = recv_lv_string (recv, MAX_ID_LENGTH).await?;
 			debug! ("Server-side proxy (P4) connected, ID {}", id);
 			P3Peer::P4ServerProxy (P4ServerProxy {
 				id,
@@ -173,8 +173,12 @@ pub async fn p3_accept_p2_stream (
 	let cmd_type = buf [0];
 	
 	Ok (match Command (cmd_type) {
-		Command::CONNECT_P2_TO_P4 => P2ToP3Stream::ConnectP2ToP4 {
+		Command::CONNECT_P2_TO_P4 => {
-			server_id: buf [1],
+			let server_id = recv_lv_string (recv, MAX_ID_LENGTH).await?;
+			
+			P2ToP3Stream::ConnectP2ToP4 {
+				server_id,
+			}
 		},
 		_ => bail! ("Invalid command type while P3 was accepting a new bi stream from P2"),
 	})
@@ -191,14 +195,19 @@ pub async fn p3_authorize_p2_to_p4_connection (
 pub async fn p4_connect_to_p3 (
 	endpoint: &quinn::Endpoint,
 	relay_addr: &std::net::SocketAddr,
-	server_id: PeerId,
+	server_id: &str,
 ) -> Result <quinn::NewConnection> 
 {
+	if server_id.as_bytes ().len () > MAX_ID_LENGTH {
+		bail! ("Server ID is longer than MAX_ID_LENGTH");
+	}
+	
 	let new_conn = endpoint.connect (relay_addr, "localhost")?.await?;
 	let (mut send, mut recv) = new_conn.connection.open_bi ().await?;
 	let cmd_type = Command::CONNECT_P4_TO_P3.0;
 	
-	send.write_all (&[cmd_type, server_id, 0, 0]).await?;
+	send.write_all (&[cmd_type, 0, 0, 0]).await?;
+	send_lv_string (&mut send, server_id).await?;
 	
 	expect_exact_response (&mut recv, [Command::OKAY.0, cmd_type, 0, 0]).await
 	.context ("P4 didn't get OK response when connecting to P3")?;
@@ -208,7 +217,7 @@ pub async fn p4_connect_to_p3 (
 
 pub enum P3ToP4Stream {
 	NewPtthConnection {
-		client_id: String,
+		client_id: PeerId,
 	}
 }