From 5e99c9f87405b99bfd558445dc6768d5edb6afd5 Mon Sep 17 00:00:00 2001
From: "Remy D. Farley" <one-d-wide@protonmail.com>
Date: Wed, 3 Apr 2024 14:20:05 +0000
Subject: [PATCH] add no-proxy mode

---
 src/args.rs     |  10 +++++
 src/lib.rs      |   3 ++
 src/no_proxy.rs | 109 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 122 insertions(+)
 create mode 100644 src/no_proxy.rs

diff --git a/src/args.rs b/src/args.rs
index 309f7d0..e7df38c 100644
--- a/src/args.rs
+++ b/src/args.rs
@@ -249,6 +249,14 @@ impl std::fmt::Display for ArgProxy {
 
 impl ArgProxy {
     pub fn from_url(s: &str) -> Result<ArgProxy> {
+        if s == "none" {
+            return Ok(ArgProxy {
+                proxy_type: ProxyType::None,
+                addr: "0.0.0.0:0".parse().unwrap(),
+                credentials: None,
+            });
+        }
+
         let e = format!("`{s}` is not a valid proxy URL");
         let url = url::Url::parse(s).map_err(|_| Error::from(&e))?;
         let e = format!("`{s}` does not contain a host");
@@ -299,6 +307,7 @@ pub enum ProxyType {
     Socks4,
     #[default]
     Socks5,
+    None,
 }
 
 impl std::fmt::Display for ProxyType {
@@ -307,6 +316,7 @@ impl std::fmt::Display for ProxyType {
             ProxyType::Socks4 => write!(f, "socks4"),
             ProxyType::Socks5 => write!(f, "socks5"),
             ProxyType::Http => write!(f, "http"),
+            ProxyType::None => write!(f, "none"),
         }
     }
 }
diff --git a/src/lib.rs b/src/lib.rs
index 6a8f699..e2701fe 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,6 +1,7 @@
 use crate::{
     directions::{IncomingDataEvent, IncomingDirection, OutgoingDirection},
     http::HttpManager,
+    no_proxy::NoProxyManager,
     session_info::{IpProtocol, SessionInfo},
     virtual_dns::VirtualDns,
 };
@@ -42,6 +43,7 @@ mod dump_logger;
 mod error;
 mod http;
 mod mobile_api;
+mod no_proxy;
 mod proxy_handler;
 mod session_info;
 mod socks;
@@ -81,6 +83,7 @@ where
         ProxyType::Socks5 => Arc::new(SocksProxyManager::new(server_addr, V5, key)) as Arc<dyn ProxyHandlerManager>,
         ProxyType::Socks4 => Arc::new(SocksProxyManager::new(server_addr, V4, key)) as Arc<dyn ProxyHandlerManager>,
         ProxyType::Http => Arc::new(HttpManager::new(server_addr, key)) as Arc<dyn ProxyHandlerManager>,
+        ProxyType::None => Arc::new(NoProxyManager::new(server_addr)) as Arc<dyn ProxyHandlerManager>,
     };
 
     let mut ipstack_config = ipstack::IpStackConfig::default();
diff --git a/src/no_proxy.rs b/src/no_proxy.rs
new file mode 100644
index 0000000..99c4dbf
--- /dev/null
+++ b/src/no_proxy.rs
@@ -0,0 +1,109 @@
+use crate::{
+    directions::{IncomingDataEvent, IncomingDirection, OutgoingDataEvent, OutgoingDirection},
+    proxy_handler::{ProxyHandler, ProxyHandlerManager},
+    session_info::SessionInfo,
+};
+use std::{collections::VecDeque, net::SocketAddr, sync::Arc};
+use tokio::sync::Mutex;
+
+struct NoProxyHandler {
+    info: SessionInfo,
+    domain_name: Option<String>,
+    client_outbuf: VecDeque<u8>,
+    server_outbuf: VecDeque<u8>,
+    udp_associate: bool,
+}
+
+#[async_trait::async_trait]
+impl ProxyHandler for NoProxyHandler {
+    fn get_session_info(&self) -> SessionInfo {
+        self.info
+    }
+
+    fn get_domain_name(&self) -> Option<String> {
+        self.domain_name.clone()
+    }
+
+    async fn push_data(&mut self, event: IncomingDataEvent<'_>) -> std::io::Result<()> {
+        let IncomingDataEvent { direction, buffer } = event;
+        match direction {
+            IncomingDirection::FromServer => {
+                self.client_outbuf.extend(buffer.iter());
+            }
+            IncomingDirection::FromClient => {
+                self.server_outbuf.extend(buffer.iter());
+            }
+        }
+        Ok(())
+    }
+
+    fn consume_data(&mut self, dir: OutgoingDirection, size: usize) {
+        let buffer = match dir {
+            OutgoingDirection::ToServer => &mut self.server_outbuf,
+            OutgoingDirection::ToClient => &mut self.client_outbuf,
+        };
+        buffer.drain(0..size);
+    }
+
+    fn peek_data(&mut self, dir: OutgoingDirection) -> OutgoingDataEvent {
+        let buffer = match dir {
+            OutgoingDirection::ToServer => &mut self.server_outbuf,
+            OutgoingDirection::ToClient => &mut self.client_outbuf,
+        };
+        OutgoingDataEvent {
+            direction: dir,
+            buffer: buffer.make_contiguous(),
+        }
+    }
+
+    fn connection_established(&self) -> bool {
+        true
+    }
+
+    fn data_len(&self, dir: OutgoingDirection) -> usize {
+        match dir {
+            OutgoingDirection::ToServer => self.server_outbuf.len(),
+            OutgoingDirection::ToClient => self.client_outbuf.len(),
+        }
+    }
+
+    fn reset_connection(&self) -> bool {
+        false
+    }
+
+    fn get_udp_associate(&self) -> Option<SocketAddr> {
+        self.udp_associate.then_some(self.info.dst)
+    }
+}
+
+pub(crate) struct NoProxyManager {
+    server: SocketAddr,
+}
+
+#[async_trait::async_trait]
+impl ProxyHandlerManager for NoProxyManager {
+    async fn new_proxy_handler(
+        &self,
+        info: SessionInfo,
+        domain_name: Option<String>,
+        udp_associate: bool,
+    ) -> std::io::Result<Arc<Mutex<dyn ProxyHandler>>> {
+        Ok(Arc::new(Mutex::new(NoProxyHandler {
+            info,
+            domain_name,
+            client_outbuf: VecDeque::default(),
+            server_outbuf: VecDeque::default(),
+            udp_associate,
+        })))
+    }
+
+    fn get_server_addr(&self) -> SocketAddr {
+        self.server
+    }
+}
+
+impl NoProxyManager {
+    pub(crate) fn new(server: SocketAddr) -> Self {
+        Self { server }
+    }
+}