Exception in async_server_base/async_connection during port scanning (nmap) #677
Description
When boost::network::http::server is listening for new connections, it sometimes throws the following exception from it's run() method (or asio::io_service::run()) when the host is being port scanned using nmap:
boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<std::system_error>>
remote_endpoint: Transport endpoint is not connected
After the exception servers stops accepting connections even if event loop is restarted and has to be stop()'ed and `listen()``ed again. In my tests, depending on the system, this may happen every time the host in nmap'ed or require several consequent nmaps.
This bug actually has already been reported (issue #360), but for an old version of cpp-netlib and there was no activity, so i decided to open a new issue. I am experiencing this problem with cpp-netlib 0.12.0.
I have fixed the issue in my project with the following patch. I am unsure if i have fixed it the right way (for example, i might have introduced breaking API change in stream_handler::remote_endpoint()), but if it is ok, i can send a pull request.
diff --git a/boost/network/protocol/http/server/async_connection.hpp b/boost/network/protocol/http/server/async_connection.hpp
index 915c6fb..eca2f68 100644
--- a/boost/network/protocol/http/server/async_connection.hpp
+++ b/boost/network/protocol/http/server/async_connection.hpp
@@ -462,11 +462,18 @@ struct async_connection
enum state_t { method, uri, version, headers };
void start() {
- typename ostringstream<Tag>::type ip_stream;
- ip_stream << socket_.remote_endpoint().address().to_string() << ':'
- << socket_.remote_endpoint().port();
- request_.source = ip_stream.str();
- read_more(method);
+ std::error_code ec;
+ auto remote_endpoint = socket_.remote_endpoint(ec);
+
+ if (ec) {
+ error_encountered = in_place<std::system_error>(ec);
+ } else {
+ typename ostringstream<Tag>::type ip_stream;
+ ip_stream << remote_endpoint.address().to_string() << ':'
+ << remote_endpoint.port();
+ request_.source = ip_stream.str();
+ read_more(method);
+ }
}
void read_more(state_t state) {
diff --git a/boost/network/protocol/stream_handler.hpp b/boost/network/protocol/stream_handler.hpp
index 16fafc6..9d82706 100644
--- a/boost/network/protocol/stream_handler.hpp
+++ b/boost/network/protocol/stream_handler.hpp
@@ -109,11 +109,11 @@ struct stream_handler {
}
}
- tcp_socket::endpoint_type remote_endpoint() const {
+ tcp_socket::endpoint_type remote_endpoint(std::error_code& ec) const {
if (ssl_enabled) {
- return ssl_sock_->next_layer().remote_endpoint();
+ return ssl_sock_->next_layer().remote_endpoint(ec);
} else {
- return tcp_sock_->remote_endpoint();
+ return tcp_sock_->remote_endpoint(ec);
}
}