From be1ac67d16de8a838e11ef19d850a4a241f71a27 Mon Sep 17 00:00:00 2001
From: alemidev <me@alemi.dev>
Date: Sun, 22 Jan 2023 19:41:07 +0100
Subject: [PATCH] feat: super cheap hack to fallback to microsoft

---
 Cargo.toml            |  1 +
 src/main.rs           | 10 +++++++---
 src/routes/session.rs | 34 ++++++++++++++++++++++++++++++----
 3 files changed, 38 insertions(+), 7 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 700d99c..b47808f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,6 +10,7 @@ clap = { version = "4", features = ["derive"] }
 tokio = { version = "1.24.2", features = ["full"] }
 sea-orm = { version = "0.10", features = [ "sqlx-postgres", "sqlx-sqlite", "runtime-tokio-rustls", "macros" ] }
 axum = "0.6.2"
+reqwest = { version = "0.11", features = ["json"] }
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 tracing-subscriber = "0.3"
diff --git a/src/main.rs b/src/main.rs
index d7f1423..9b75628 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -16,7 +16,7 @@ use tracing::{info, metadata::LevelFilter};
 
 use crate::routes::{
 	auth::{authenticate, validate, refresh},
-	session::{join, has_joined, profile},
+	session::{join, has_joined_wrapper, profile},
 };
 
 /// Reimplementation of legacy auth server for minecraft
@@ -33,6 +33,10 @@ struct ConfigArgs {
 	/// Valid time for join requests, in seconds
 	#[arg(short, long, default_value_t = 10)]
 	time_window: u32,
+
+	/// Enable join request fallback to Microsoft
+	#[arg(long)]
+	fallback: bool,
 }
 
 #[derive(Clone)]
@@ -76,14 +80,14 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
 		.route("/auth/refresh", post(refresh)) //in: token out: refreshed token
 		// SESSION
 		.route("/session/minecraft/join", post(join))
-		.route("/session/minecraft/hasJoined", get(has_joined))
+		.route("/session/minecraft/hasJoined", get(has_joined_wrapper))
 		.route("/session/minecraft/profile/:user_id", get(profile))
 		// CUSTOM
 		.route("/register", post(register_tmp))
 		.fallback(fallback_route)
 		.with_state(AppState { store, db, cfg });
 
-	info!(target: "MAIN", "serving app...");
+	info!(target: "MAIN", "serving Yggdrasil on {}", &addr);
 
 	axum::Server::bind(&addr)
 		.serve(app.into_make_service())
diff --git a/src/routes/session.rs b/src/routes/session.rs
index 7e83205..1037c7d 100644
--- a/src/routes/session.rs
+++ b/src/routes/session.rs
@@ -29,10 +29,36 @@ pub async fn join(State(state): State<AppState>, Json(payload): Json<proto::Join
 	}
 }
 
-pub async fn has_joined(State(state): State<AppState>, Query(query): Query<HashMap<String, String>>) -> Result<Json<proto::JoinResponse>, StatusCode> {
-	let username = query.get("username").unwrap().clone();
-	let server_id = query.get("serverId").unwrap();
-	info!(target: "SESSION", "[HAS_JOINED] called with user:{} server:{}", username, server_id);
+pub async fn has_joined_wrapper(State(state): State<AppState>, Query(query): Query<HashMap<String, String>>) -> Result<Json<proto::JoinResponse>, StatusCode> {
+	let username  = query.get("username").ok_or(StatusCode::UNPROCESSABLE_ENTITY)?;
+	let server_id = query.get("serverId").ok_or(StatusCode::UNPROCESSABLE_ENTITY)?;
+	let user_ip   = query.get("ip");
+
+	match has_joined_local(&state, username, server_id, user_ip).await {
+		Ok(r) => Ok(r),
+		Err(e) => {
+			if state.cfg.fallback {
+				Ok(has_joined_microsoft(&state, username, server_id, user_ip).await?)
+			} else {
+				Err(e)
+			}
+		}
+	}
+}
+
+pub async fn has_joined_microsoft(_state: &AppState, username: &String, server_id: &String, _user_ip: Option<&String>) -> Result<Json<proto::JoinResponse>, StatusCode> {
+	Ok(
+		Json( // TODO don't do it with a format!!!
+			reqwest::get(format!("https://sessionserver.mojang.com/session/minecraft/hasJoined?username={}&serverId={}", username, server_id)) 
+				.await.map_err(|_| StatusCode::SERVICE_UNAVAILABLE)?
+				.json::<proto::JoinResponse>()
+				.await.map_err(|_| StatusCode::UNAUTHORIZED)?
+		)
+	)
+}
+
+pub async fn has_joined_local(state: &AppState, username: &String, server_id: &String, user_ip: Option<&String>) -> Result<Json<proto::JoinResponse>, StatusCode> {
+	info!(target: "SESSION", "[HAS_JOINED] called with user:{} server:{} ip:{:?}", username, server_id, user_ip);
 
 	let user = entities::user::Entity::find().filter(
 		entities::user::Column::Name.eq(username.clone())