From d5154f0a5da5971df3a3ab4ea1d499f2bd4cafda Mon Sep 17 00:00:00 2001
From: Martin Michelsen <fuzziqersoftware+g@gmail.com>
Date: Tue, 4 Oct 2022 23:42:49 -0700
Subject: [PATCH] close proxy session early if client intentionally disconnects

---
 src/ProxyCommands.cc | 9 ++++++++-
 src/ProxyServer.cc   | 4 ++++
 src/ProxyServer.hh   | 1 +
 3 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/ProxyCommands.cc b/src/ProxyCommands.cc
index 977f2a14..de9f9c5a 100644
--- a/src/ProxyCommands.cc
+++ b/src/ProxyCommands.cc
@@ -114,6 +114,12 @@ static HandlerResult S_invalid(shared_ptr<ServerState>,
   return HandlerResult::Type::SUPPRESS;
 }
 
+static HandlerResult C_05(shared_ptr<ServerState>,
+    ProxyServer::LinkedSession& session, uint16_t, uint32_t, string&) {
+  session.close_on_disconnect = true;
+  return HandlerResult::Type::FORWARD;
+}
+
 static HandlerResult S_97(shared_ptr<ServerState>,
     ProxyServer::LinkedSession& session, uint16_t, uint32_t flag, string&) {
   // If the client has already received a 97 command, block this one and
@@ -1303,6 +1309,7 @@ static HandlerResult C_V123_A0_A1(shared_ptr<ServerState>,
   // For licensed sessions, send them back to newserv's main menu instead of
   // going to the remote server's ship/block select menu
   session.send_to_game_server();
+  session.close_on_disconnect = true;
   return HandlerResult::Type::SUPPRESS;
 }
 
@@ -1316,7 +1323,7 @@ static on_command_t handlers[0x100][6][2] = {
 /* 02 */ {{S_V123P_02_17, nullptr}, {S_V123P_02_17, nullptr},      {S_V123P_02_17, nullptr},      {S_V123P_02_17, nullptr},      {S_V123P_02_17, nullptr},      {nullptr,      nullptr}},
 /* 03 */ {{S_invalid,     nullptr}, {nullptr,       nullptr},      {nullptr,       nullptr},      {nullptr,       nullptr},      {nullptr,       nullptr},      {S_B_03,       nullptr}},
 /* 04 */ {{nullptr,       nullptr}, {S_V123_04,     nullptr},      {S_V123_04,     nullptr},      {S_V123_04,     nullptr},      {S_V123_04,     nullptr},      {nullptr,      nullptr}},
-/* 05 */ {{nullptr,       nullptr}, {nullptr,       nullptr},      {nullptr,       nullptr},      {nullptr,       nullptr},      {nullptr,       nullptr},      {nullptr,      nullptr}},
+/* 05 */ {{nullptr,       C_05},    {nullptr,       C_05},         {nullptr,       C_05},         {nullptr,       C_05},         {nullptr,       C_05},         {nullptr,      C_05}},
 /* 06 */ {{nullptr,       nullptr}, {S_V123_06,     C_06},         {S_V123_06,     C_06},         {S_V123_06,     C_06},         {S_V123_06,     C_06},         {nullptr,      C_06}},
 /* 07 */ {{nullptr,       nullptr}, {nullptr,       nullptr},      {nullptr,       nullptr},      {nullptr,       nullptr},      {nullptr,       nullptr},      {nullptr,      nullptr}},
 /* 08 */ {{nullptr,       nullptr}, {nullptr,       nullptr},      {nullptr,       nullptr},      {nullptr,       nullptr},      {nullptr,       nullptr},      {nullptr,      nullptr}},
diff --git a/src/ProxyServer.cc b/src/ProxyServer.cc
index 389303ab..73bef8d3 100644
--- a/src/ProxyServer.cc
+++ b/src/ProxyServer.cc
@@ -469,6 +469,7 @@ ProxyServer::LinkedSession::LinkedSession(
       TerminalFormat::FG_YELLOW,
       TerminalFormat::FG_RED),
     local_port(local_port),
+    close_on_disconnect(false),
     remote_ip_crc(0),
     enable_remote_ip_crc_patch(false),
     version(version),
@@ -660,6 +661,9 @@ void ProxyServer::LinkedSession::on_error(Channel& ch, short events) {
       session->send_to_game_server("The server has\ndisconnected.");
     }
     session->disconnect();
+    if (session->close_on_disconnect) {
+      session->server->delete_session(session->id);
+    }
   }
 }
 
diff --git a/src/ProxyServer.hh b/src/ProxyServer.hh
index c2275627..2b7ee125 100644
--- a/src/ProxyServer.hh
+++ b/src/ProxyServer.hh
@@ -45,6 +45,7 @@ public:
     Channel server_channel;
     uint16_t local_port;
     struct sockaddr_storage next_destination;
+    bool close_on_disconnect;
 
     uint8_t prev_server_command_bytes[6];
     uint32_t remote_ip_crc;