From f1dcd96e42990d5d506cd9215f246353fd4b1d63 Mon Sep 17 00:00:00 2001
From: Andrea Bondavalli <andrea.bondavalli74@gmail.com>
Date: Wed, 25 Nov 2020 12:46:51 +0100
Subject: [PATCH] Fix for incorrect SAP packets TTL This fixes issue #25

---
 daemon/sap.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/daemon/sap.cpp b/daemon/sap.cpp
index 51d9ccb..804940d 100644
--- a/daemon/sap.cpp
+++ b/daemon/sap.cpp
@@ -51,6 +51,14 @@ bool SAP::set_multicast_interface(const std::string& interface_ip) {
     BOOST_LOG_TRIVIAL(error) << "sap::enable_loopback option " << ec.message();
     return false;
   }
+
+  /* https://tools.ietf.org/html/rfc2974  ttl = 255 */
+  boost::asio::ip::multicast::hops ttl_option(255);
+  socket_.set_option(ttl_option, ec);
+  if (ec) {
+    BOOST_LOG_TRIVIAL(error) << "sap::hops/ttl option " << ec.message();
+    return false;
+  }
   return true;
 }