fix(gateway): resolve TCP Connection Reset issue on Keep-Alive clients

Author: yinheli

src/gateway/nat.rs

@@ -9,10 +9,13 @@ use tokio::sync::{RwLock, mpsc::UnboundedSender};
 
 use moka::future::Cache;
 
+use std::collections::hash_map::DefaultHasher;
+use std::hash::{Hash, Hasher};
+
 pub struct Nat {
     nat_type: Type,
-    cache: Cache<u32, Arc<Session>>,
-    mapping: Arc<RwLock<BiMap<u32, u16>>>,
+    cache: Cache<u64, Arc<Session>>,
+    mapping: Arc<RwLock<BiMap<u64, u16>>>,
 }
 
 pub enum Type {
@@ -32,8 +35,8 @@ pub struct Session {
 impl Nat {
     pub fn new(nat_type: Type, tx: Option<UnboundedSender<u16>>) -> Self {
         let ttl = match nat_type {
-            Type::Tcp => Duration::from_secs(60),
-            Type::Udp => Duration::from_secs(20),
+            Type::Tcp => Duration::from_secs(600),
+            Type::Udp => Duration::from_secs(60),
         };
 
         let mapping = Arc::new(RwLock::new(BiMap::new()));
@@ -53,7 +56,12 @@ impl Nat {
         dst_addr: Ipv4Addr,
         dst_port: u16,
     ) -> Result<Session, Error> {
-        let addr_key = u32::from_be_bytes(src_addr.octets()) + src_port as u32;
+        let mut hasher = DefaultHasher::new();
+        src_addr.hash(&mut hasher);
+        src_port.hash(&mut hasher);
+        dst_addr.hash(&mut hasher);
+        dst_port.hash(&mut hasher);
+        let addr_key = hasher.finish();
 
         if let Some(session) = self.cache.get(&addr_key).await {
             return Ok(*session);
@@ -121,13 +129,13 @@ impl Nat {
 
     fn new_cache(
         ttl: Duration,
-        mapping: Arc<RwLock<BiMap<u32, u16>>>,
+        mapping: Arc<RwLock<BiMap<u64, u16>>>,
         tx: Option<UnboundedSender<u16>>,
-    ) -> Cache<u32, Arc<Session>> {
+    ) -> Cache<u64, Arc<Session>> {
         Cache::builder()
             .max_capacity(5000)
             .time_to_idle(ttl)
-            .eviction_listener(move |addr_key: Arc<u32>, session: Arc<Session>, _cause| {
+            .eviction_listener(move |addr_key: Arc<u64>, session: Arc<Session>, _cause| {
                 let mapping = mapping.clone();
                 let tx = tx.clone();
                 tokio::task::spawn(async move {
@@ -141,7 +149,7 @@ impl Nat {
             .build()
     }
 
-    async fn get_addr_key_by_port_fast(&self, nat_port: &u16) -> Option<u32> {
+    async fn get_addr_key_by_port_fast(&self, nat_port: &u16) -> Option<u64> {
         let mapping = self.mapping.read().await;
         mapping.get_by_right(nat_port).copied()
     }