From aaf882656086171e0711c62f9817b9bd22b3472d Mon Sep 17 00:00:00 2001
From: Cecylia Bocovich <cohosh@torproject.org>
Date: Wed, 23 Oct 2024 09:38:14 -0400
Subject: [PATCH] Add proxy event for when client has connected

This enables the usage of callbacks that will be called when a client
has opened a data channel connection to the proxy.
---
 common/event/interface.go | 8 ++++++++
 proxy/lib/snowflake.go    | 1 +
 2 files changed, 9 insertions(+)

diff --git a/common/event/interface.go b/common/event/interface.go
index 38dd6d7..f7001ba 100644
--- a/common/event/interface.go
+++ b/common/event/interface.go
@@ -67,6 +67,14 @@ func (e EventOnProxyStarting) String() string {
 	return "Proxy starting"
 }
 
+type EventOnProxyClientConnected struct {
+	SnowflakeEvent
+}
+
+func (e EventOnProxyClientConnected) String() string {
+	return fmt.Sprintf("client connected")
+}
+
 type EventOnProxyConnectionOver struct {
 	SnowflakeEvent
 	InboundTraffic  int64
diff --git a/proxy/lib/snowflake.go b/proxy/lib/snowflake.go
index 9041f60..442e013 100644
--- a/proxy/lib/snowflake.go
+++ b/proxy/lib/snowflake.go
@@ -449,6 +449,7 @@ func (sf *SnowflakeProxy) makePeerConnectionFromOffer(
 
 		dc.OnOpen(func() {
 			log.Printf("Data Channel %s-%d open\n", dc.Label(), dc.ID())
+			sf.EventDispatcher.OnNewSnowflakeEvent(event.EventOnProxyClientConnected{})
 
 			if sf.OutboundAddress != "" {
 				selectedCandidatePair, err := pc.SCTP().Transport().ICETransport().GetSelectedCandidatePair()