diff --git a/include/boost/asio/ssl/detail/impl/engine.ipp b/include/boost/asio/ssl/detail/impl/engine.ipp
index 9142a5df3..29948d5f5 100644
--- a/include/boost/asio/ssl/detail/impl/engine.ipp
+++ b/include/boost/asio/ssl/detail/impl/engine.ipp
@@ -17,6 +17,7 @@
 
 #include <boost/asio/detail/config.hpp>
 
+#include <boost/asio/detail/assert.hpp>
 #include <boost/asio/detail/throw_error.hpp>
 #include <boost/asio/error.hpp>
 #include <boost/asio/ssl/detail/engine.hpp>
@@ -274,8 +275,15 @@ engine::want engine::perform(int (engine::* op)(void*, std::size_t),
     ec = boost::asio::error::eof;
     return want_nothing;
   }
+  else if (ssl_error == SSL_ERROR_ZERO_RETURN)
+  {
+    ec = boost::asio::error::eof;
+    return want_nothing;
+  }
   else
   {
+    BOOST_ASIO_ASSERT(result > 0);
+    //if(result <= 0) std::cerr << "result <= 0, ssl_error = " << ssl_error << std::endl;
     ec = boost::system::error_code();
     return want_nothing;
   }