Trial decrypt for old versions of the request packet

auth/callback.go

@@ -107,10 +107,19 @@ func (m *Manager) handleRequest(cmixMsg format.Message,
 	jww.TRACE.Printf("handleRequest ECRPAYLOAD: %v", baseFmt.GetEcrPayload())
 	jww.TRACE.Printf("handleRequest MAC: %v", cmixMsg.GetMac())
 
+	ecrPayload := baseFmt.GetEcrPayload()
 	success, payload := cAuth.Decrypt(myHistoricalPrivKey,
-		partnerPubKey, baseFmt.GetEcrPayload(),
+		partnerPubKey, ecrPayload,
 		cmixMsg.GetMac(), grp)
 
+	if !success {
+		jww.WARN.Printf("Attempting to decrypt old request packet...")
+		ecrPayload = append(ecrPayload, baseFmt.GetVersion())
+		success, payload = cAuth.Decrypt(myHistoricalPrivKey,
+			partnerPubKey, ecrPayload,
+			cmixMsg.GetMac(), grp)
+	}
+
 	if !success {
 		jww.WARN.Printf("Received auth request failed " +
 			"its mac check")