From 169e5d33cd97533bcd5e679ec6e1401a2c4571f5 Mon Sep 17 00:00:00 2001
From: Jeff Becker <jeff@lokinet.io>
Date: Thu, 27 Apr 2023 19:15:58 -0400
Subject: [PATCH] Redo wire protocol race condition fix.

In commit a76acd49560f9845c2ad9a839364f2834afc7756 we attempted to fix
issues on service nodes that related to spamming service nodes with
traffc, but this caused a regression where clients could not connect
to the network.

However, we also did something idiotic with the protocol handshake.
The handshake logic was modified and caused client connections to
fail. This was due to a change in how we decided what a timed out
session is. We redo the close bug and revert the change to the
protocol handshake.

(cherry picked from commit b0b6e2b198ba32e8c5641e99494d2874b2243b8f)
---
 llarp/iwp/session.cpp   | 9 ++++-----
 llarp/iwp/session.hpp   | 1 -
 llarp/router/router.cpp | 4 ++--
 3 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/llarp/iwp/session.cpp b/llarp/iwp/session.cpp
index 75f2356a5..c8c7e7fa8 100644
--- a/llarp/iwp/session.cpp
+++ b/llarp/iwp/session.cpp
@@ -144,6 +144,8 @@ namespace llarp
     void
     Session::EncryptAndSend(ILinkSession::Packet_t data)
     {
+      if (m_State == State::Closed)
+        return;
       m_EncryptNext.emplace_back(std::move(data));
       TriggerPump();
       if (!IsEstablished())
@@ -179,12 +181,9 @@ namespace llarp
         return;
       auto close_msg = CreatePacket(Command::eCLOS, 0, 16, 16);
       m_Parent->UnmapAddr(m_RemoteAddr);
-      m_State = State::Closed;
-      if (m_SentClosed.test_and_set())
-        return;
       EncryptAndSend(std::move(close_msg));
-
       LogInfo(m_Parent->PrintableName(), " closing connection to ", m_RemoteAddr);
+      m_State = State::Closed;
     }
 
     bool
@@ -355,7 +354,7 @@ namespace llarp
     bool
     Session::TimedOut(llarp_time_t now) const
     {
-      if (m_State == State::Ready)
+      if (m_State == State::Ready || m_State == State::LinkIntro)
       {
         return now > m_LastRX
             && now - m_LastRX
diff --git a/llarp/iwp/session.hpp b/llarp/iwp/session.hpp
index 210a37a1e..1e0e6b3c4 100644
--- a/llarp/iwp/session.hpp
+++ b/llarp/iwp/session.hpp
@@ -206,7 +206,6 @@ namespace llarp
 
       std::atomic_flag m_PlaintextEmpty;
       llarp::thread::Queue<CryptoQueue_t> m_PlaintextRecv;
-      std::atomic_flag m_SentClosed;
 
       void
       EncryptWorker(CryptoQueue_t msgs);
diff --git a/llarp/router/router.cpp b/llarp/router/router.cpp
index c1d8e8595..9313f03cc 100644
--- a/llarp/router/router.cpp
+++ b/llarp/router/router.cpp
@@ -482,8 +482,8 @@ namespace llarp
       LogError("RC is invalid, not saving");
       return false;
     }
-    if (m_isServiceNode)
-      _nodedb->Put(_rc);
+    if (IsServiceNode())
+      _nodedb->Put(rc());
     QueueDiskIO([&]() { HandleSaveRC(); });
     return true;
   }