From e745141b512761921e777ac107a22d3ac54172c5 Mon Sep 17 00:00:00 2001
From: Christian Ulrich <christian@ulrich.earth>
Date: Sun, 23 Aug 2020 15:17:19 +0200
Subject: [PATCH] have to resend ACK, not SYN+ACK

---
 tcp_syni.nim | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tcp_syni.nim b/tcp_syni.nim
index f3be199..4e51ac8 100644
--- a/tcp_syni.nim
+++ b/tcp_syni.nim
@@ -80,7 +80,7 @@ proc captureSeqNumbers(puncher: TcpSyniPuncher, rawFd: AsyncFD,
           break
   await cb(seqNums)
 
-proc captureAndResendSynAck(puncher: TcpSyniPuncher, rawFd: AsyncFD) {.async.} =
+proc captureAndResendAck(puncher: TcpSyniPuncher, rawFd: AsyncFD) {.async.} =
   while true:
     let packet = await rawFd.recv(4000)
     if packet == "":
@@ -90,7 +90,7 @@ proc captureAndResendSynAck(puncher: TcpSyniPuncher, rawFd: AsyncFD) {.async.} =
        parsed.ipAddrSrc == puncher.srcIp and
        parsed.tcpPortSrc.int == puncher.srcPort.int and
        parsed.ipAddrDst == puncher.dstIp and
-       parsed.tcpFlags == {SYN, ACK}:
+       parsed.tcpFlags == {ACK}:
       for port in puncher.dstPorts:
         if parsed.tcpPortDst.int == port.int:
           let ipPacket = IpPacket(protocol: tcp,
@@ -158,9 +158,9 @@ proc connect*(puncher: TcpSyniPuncher,
               progressCb: PunchProgressCb): Future[AsyncSocket] {.async.} =
   let iface = fromIpAddress(puncher.srcIp)
   let captureSeqFd = setupEthernetCapturingSocket(iface)
-  let captureSynAckFd = setupEthernetCapturingSocket(iface)
+  let captureAckFd = setupEthernetCapturingSocket(iface)
   asyncCheck puncher.captureSeqNumbers(captureSeqFd, progressCb)
-  asyncCheck puncher.captureAndResendSynAck(captureSynAckFd)
+  asyncCheck puncher.captureAndResendAck(captureAckFd)
   await puncher.addFirewallRules()
   try:
     result = await puncher.connectParallel()