Aborted data should not be passed to recv function

append_paylaod is no longer needed.

Author: GreaterFire

docs/config.md

@@ -16,7 +16,6 @@ In this page, we will look at the config file of trojan. Trojan uses [`JSON`](ht
     "password": [
         "password1"
     ],
-    "append_payload": true,
     "log_level": 1,
     "ssl": {
         "verify": true,
@@ -47,7 +46,6 @@ In this page, we will look at the config file of trojan. Trojan uses [`JSON`](ht
 - `remote_addr`: server address (hostname)
 - `remote_port`: server port
 - `password`: password used for verification (only the first password in the array will be used)
-- `append_payload`: whether to append the first packet to trojan request. It can reduce length patterns of sessions, but may cause stability issues, in which case set it to `false`. For example, if you are running trojan server and trojan client on the same machine, you should set this option to `false`, because there is a race condition at the time the client receives its first packet.
 - `log_level`: how much log to dump. 0: ALL; 1: INFO; 2: WARN; 3: ERROR; 4: FATAL; 5: OFF.
 - `ssl`: `SSL` specific configurations
     - `verify`: whether to verify `SSL` certificate **STRONGLY RECOMMENDED**
@@ -81,7 +79,6 @@ This forward config is for port forwarding. Everything is the same as the client
     "password": [
         "password1"
     ],
-    "append_payload": true,
     "udp_timeout": 60,
     "log_level": 1,
     "ssl": {

examples/client.json-example

@@ -7,7 +7,6 @@
     "password": [
         "password1"
     ],
-    "append_payload": true,
     "log_level": 1,
     "ssl": {
         "verify": true,

examples/forward.json-example

@@ -9,7 +9,6 @@
     "password": [
         "password1"
     ],
-    "append_payload": true,
     "udp_timeout": 60,
     "log_level": 1,
     "ssl": {

src/clientsession.cpp

@@ -60,7 +60,10 @@ void ClientSession::start() {
 void ClientSession::in_async_read() {
     auto self = shared_from_this();
     in_socket.async_read_some(boost::asio::buffer(in_read_buf, MAX_LENGTH), [this, self](const boost::system::error_code error, size_t length) {
-        if (error && error != boost::asio::error::operation_aborted) {
+        if (error == boost::asio::error::operation_aborted) {
+            return;
+        }
+        if (error) {
             destroy();
             return;
         }
@@ -106,7 +109,10 @@ void ClientSession::out_async_write(const string &data) {
 void ClientSession::udp_async_read() {
     auto self = shared_from_this();
     udp_socket.async_receive_from(boost::asio::buffer(udp_read_buf, MAX_LENGTH), udp_recv_endpoint, [this, self](const boost::system::error_code error, size_t length) {
-        if (error && error != boost::asio::error::operation_aborted) {
+        if (error == boost::asio::error::operation_aborted) {
+            return;
+        }
+        if (error) {
             destroy();
             return;
         }
@@ -211,17 +217,9 @@ void ClientSession::in_sent() {
         }
         case REQUEST: {
             status = CONNECT;
+            in_async_read();
             if (is_udp) {
-                in_async_read();
-            }
-            if (config.append_payload) {
-                if (is_udp) {
-                    udp_async_read();
-                } else {
-                    in_async_read();
-                }
-            } else {
-                first_packet_recv = true;
+                udp_async_read();
             }
             auto self = shared_from_this();
             resolver.async_resolve(config.remote_addr, to_string(config.remote_port), [this, self](const boost::system::error_code error, tcp::resolver::results_type results) {

src/config.cpp

@@ -59,7 +59,6 @@ void Config::populate(const ptree &tree) {
         string p = item.second.get_value<string>();
         password[SHA224(p)] = p;
     }
-    append_payload = tree.get("append_payload", true);
     udp_timeout = tree.get("udp_timeout", 60);
     log_level = static_cast<Log::Level>(tree.get("log_level", 1));
     ssl.verify = tree.get("ssl.verify", true);

src/config.h

@@ -39,7 +39,6 @@ class Config {
     std::string target_addr;
     uint16_t target_port;
     std::map<std::string, std::string> password;
-    bool append_payload;
     int udp_timeout;
     Log::Level log_level;
     class SSLConfig {

src/forwardsession.cpp

@@ -54,11 +54,7 @@ void ForwardSession::start() {
         }
     }
     out_write_buf = TrojanRequest::generate(config.password.cbegin()->first, config.target_addr, config.target_port, true);
-    if (config.append_payload) {
-        in_async_read();
-    } else {
-        first_packet_recv = true;
-    }
+    in_async_read();
     Log::log_with_endpoint(in_endpoint, "forwarding to " + config.target_addr + ':' + to_string(config.target_port) + " via " + config.remote_addr + ':' + to_string(config.remote_port), Log::INFO);
     auto self = shared_from_this();
     resolver.async_resolve(config.remote_addr, to_string(config.remote_port), [this, self](const boost::system::error_code error, tcp::resolver::results_type results) {
@@ -123,7 +119,10 @@ void ForwardSession::start() {
 void ForwardSession::in_async_read() {
     auto self = shared_from_this();
     in_socket.async_read_some(boost::asio::buffer(in_read_buf, MAX_LENGTH), [this, self](const boost::system::error_code error, size_t length) {
-        if (error && error != boost::asio::error::operation_aborted) {
+        if (error == boost::asio::error::operation_aborted) {
+            return;
+        }
+        if (error) {
             destroy();
             return;
         }

tests/LinuxSmokeTest/client.json

@@ -7,7 +7,6 @@
     "password": [
         "linux-smoke-test-password"
     ],
-    "append_payload": false,
     "log_level": 0,
     "ssl": {
         "verify": true,

tests/LinuxSmokeTest/fake-client.json

@@ -7,7 +7,6 @@
     "password": [
         "wrong-password"
     ],
-    "append_payload": false,
     "log_level": 0,
     "ssl": {
         "verify": true,

tests/LinuxSmokeTest/forward.json

@@ -9,7 +9,6 @@
     "password": [
         "linux-smoke-test-password"
     ],
-    "append_payload": false,
     "udp_timeout": 60,
     "log_level": 0,
     "ssl": {