From 055fb51ed9c1b44bcc790613b71720e85aeaf83d Mon Sep 17 00:00:00 2001
From: RPRX <63339210+rprx@users.noreply.github.com>
Date: Fri, 5 Mar 2021 12:06:37 +0000
Subject: [PATCH] Apply UDPOverride to Freedom Outbound PacketReader

---
 proxy/freedom/freedom.go | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/proxy/freedom/freedom.go b/proxy/freedom/freedom.go
index 7a8c336a..95ba4fdc 100644
--- a/proxy/freedom/freedom.go
+++ b/proxy/freedom/freedom.go
@@ -169,7 +169,7 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 		if destination.Network == net.Network_TCP {
 			reader = buf.NewReader(conn)
 		} else {
-			reader = NewPacketReader(conn)
+			reader = NewPacketReader(conn, UDPOverride)
 		}
 		if err := buf.Copy(reader, output, buf.UpdateActivity(timer)); err != nil {
 			return newError("failed to process response").Base(err)
@@ -185,7 +185,7 @@ func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer inte
 	return nil
 }
 
-func NewPacketReader(conn net.Conn) buf.Reader {
+func NewPacketReader(conn net.Conn, UDPOverride net.Destination) buf.Reader {
 	iConn := conn
 	statConn, ok := iConn.(*internet.StatCouterConnection)
 	if ok {
@@ -199,6 +199,7 @@ func NewPacketReader(conn net.Conn) buf.Reader {
 		return &PacketReader{
 			PacketConnWrapper: c,
 			Counter:           counter,
+			UDPOverride:       UDPOverride,
 		}
 	}
 	return &buf.PacketReader{Reader: conn}
@@ -207,6 +208,7 @@ func NewPacketReader(conn net.Conn) buf.Reader {
 type PacketReader struct {
 	*internet.PacketConnWrapper
 	stats.Counter
+	UDPOverride net.Destination
 }
 
 func (r *PacketReader) ReadMultiBuffer() (buf.MultiBuffer, error) {
@@ -223,6 +225,12 @@ func (r *PacketReader) ReadMultiBuffer() (buf.MultiBuffer, error) {
 		Port:    net.Port(d.(*net.UDPAddr).Port),
 		Network: net.Network_UDP,
 	}
+	if r.UDPOverride.Address != nil {
+		b.UDP.Address = r.UDPOverride.Address
+	}
+	if r.UDPOverride.Port != 0 {
+		b.UDP.Port = r.UDPOverride.Port
+	}
 	if r.Counter != nil {
 		r.Counter.Add(int64(n))
 	}