From 97519bf76c634e775689f6105cc683fa62138d60 Mon Sep 17 00:00:00 2001
From: vyzo <vyzo@hackzen.org>
Date: Sat, 28 Mar 2020 12:22:57 +0200
Subject: [PATCH] better handling of message originating from self but
 forwarded by another peer

---
 pubsub.go | 14 ++++++++------
 tracer.go |  1 +
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/pubsub.go b/pubsub.go
index a4f86e9..b0a88ed 100644
--- a/pubsub.go
+++ b/pubsub.go
@@ -832,6 +832,14 @@ func (p *PubSub) pushMsg(msg *Message) {
 		return
 	}
 
+	// reject messages claiming to be from ourselves but not locally published
+	self := p.host.ID()
+	if peer.ID(msg.GetFrom()) == self && src != self {
+		log.Debugf("dropping message claiming to be from self but forwarded from %s", src)
+		p.tracer.RejectMessage(msg, rejectSelfOrigin)
+		return
+	}
+
 	// have we already seen and validated this message?
 	id := p.msgID(msg.Message)
 	if p.seenMessage(id) {
@@ -849,12 +857,6 @@ func (p *PubSub) pushMsg(msg *Message) {
 }
 
 func (p *PubSub) publishMessage(msg *Message) {
-	self := p.host.ID()
-	if peer.ID(msg.GetFrom()) == self && msg.ReceivedFrom != self {
-		// we don't publish messages claiming to be from us but not published by ourselves
-		return
-	}
-
 	p.tracer.DeliverMessage(msg)
 	p.notifySubs(msg)
 	p.rt.Publish(msg)
diff --git a/tracer.go b/tracer.go
index 613d70e..63277d4 100644
--- a/tracer.go
+++ b/tracer.go
@@ -33,6 +33,7 @@ const (
 	rejectValidationQueueFull = "validation queue full"
 	rejectValidationThrottled = "validation throttled"
 	rejectValidationFailed    = "validation failed"
+	rejectSelfOrigin          = "self originated message"
 )
 
 type basicTracer struct {