From a1840b322176a87c585dfb8b680799b41f45682f Mon Sep 17 00:00:00 2001
From: Marten Seemann <martenseemann@gmail.com>
Date: Thu, 2 Jan 2020 14:36:25 +0800
Subject: [PATCH] fix unmarshaling of transport parameters from session tickets

---
 internal/handshake/crypto_setup.go         | 8 +++++++-
 internal/handshake/transport_parameters.go | 3 +--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/internal/handshake/crypto_setup.go b/internal/handshake/crypto_setup.go
index 9f5aa1c3a..c4ca769cc 100644
--- a/internal/handshake/crypto_setup.go
+++ b/internal/handshake/crypto_setup.go
@@ -491,7 +491,13 @@ func (h *cryptoSetup) accept0RTT(sessionTicketData []byte) bool {
 		h.logger.Debugf("Unmarshaling transport parameters from session ticket failed: %s", err.Error())
 		return false
 	}
-	return h.ourParams.ValidFor0RTT(&tp)
+	valid := h.ourParams.ValidFor0RTT(&tp)
+	if valid {
+		h.logger.Debugf("Accepting 0-RTT.")
+	} else {
+		h.logger.Debugf("Transport parameters changed. Rejecting 0-RTT.")
+	}
+	return valid
 }
 
 func (h *cryptoSetup) handlePostHandshakeMessage() {
diff --git a/internal/handshake/transport_parameters.go b/internal/handshake/transport_parameters.go
index 4ab0826f4..d97ee2d10 100644
--- a/internal/handshake/transport_parameters.go
+++ b/internal/handshake/transport_parameters.go
@@ -413,8 +413,7 @@ func (p *TransportParameters) UnmarshalFromSessionTicket(data []byte) error {
 	if version != transportParameterMarshalingVersion {
 		return fmt.Errorf("unknown transport parameter marshaling version: %d", version)
 	}
-	tp := &TransportParameters{}
-	return tp.Unmarshal(data[len(data)-r.Len():], protocol.PerspectiveServer)
+	return p.Unmarshal(data[len(data)-r.Len():], protocol.PerspectiveServer)
 }
 
 // ValidFor0RTT checks if the transport parameters match those saved in the session ticket.