bd77bb41df
Like suggested by RFC 2663, reprogram the dissolve timeout of a TCP link state to 2 times the maximum segment lifetime (by default 1 minute) when receiving a matching packet with the FIN flag set, or with the ACK flag set to acknowledge a FIN of the remote side. Mark a link state as closed (no further reprogramming of the dissolve timeout) and set the dissolve timeout to 2 times the maximum segment lifetime when receiving a packet with the RESET flag set. Issue #2953
286 lines
7.7 KiB
C++
286 lines
7.7 KiB
C++
/*
|
|
* \brief State tracking for UDP/TCP connections
|
|
* \author Martin Stein
|
|
* \date 2016-08-19
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2016-2017 Genode Labs GmbH
|
|
*
|
|
* This file is part of the Genode OS framework, which is distributed
|
|
* under the terms of the GNU Affero General Public License version 3.
|
|
*/
|
|
|
|
/* Genode includes */
|
|
#include <net/tcp.h>
|
|
|
|
/* local includes */
|
|
#include <link.h>
|
|
#include <configuration.h>
|
|
|
|
using namespace Net;
|
|
using namespace Genode;
|
|
|
|
|
|
/******************
|
|
** Link_side_id **
|
|
******************/
|
|
|
|
constexpr size_t Link_side_id::data_size()
|
|
{
|
|
return sizeof(src_ip) + sizeof(src_port) +
|
|
sizeof(dst_ip) + sizeof(dst_port);
|
|
}
|
|
|
|
|
|
bool Link_side_id::operator == (Link_side_id const &id) const
|
|
{
|
|
return memcmp(id.data_base(), data_base(), data_size()) == 0;
|
|
}
|
|
|
|
|
|
bool Link_side_id::operator > (Link_side_id const &id) const
|
|
{
|
|
return memcmp(id.data_base(), data_base(), data_size()) > 0;
|
|
}
|
|
|
|
|
|
/***************
|
|
** Link_side **
|
|
***************/
|
|
|
|
Link_side::Link_side(Domain &domain,
|
|
Link_side_id const &id,
|
|
Link &link)
|
|
:
|
|
_domain(domain), _id(id), _link(link)
|
|
{
|
|
if (link.config().verbose()) {
|
|
log("[", domain, "] new ", l3_protocol_name(link.protocol()),
|
|
" link ", is_client() ? "client" : "server", ": ", *this);
|
|
}
|
|
}
|
|
|
|
|
|
Link_side const &Link_side::find_by_id(Link_side_id const &id) const
|
|
{
|
|
if (id == _id) {
|
|
return *this; }
|
|
|
|
bool const side = id > _id;
|
|
Link_side *const link_side = Avl_node<Link_side>::child(side);
|
|
if (!link_side) {
|
|
throw Link_side_tree::No_match(); }
|
|
|
|
return link_side->find_by_id(id);
|
|
}
|
|
|
|
|
|
void Link_side::print(Output &output) const
|
|
{
|
|
Genode::print(output, "src ", src_ip(), ":", src_port(),
|
|
" dst ", dst_ip(), ":", dst_port());
|
|
}
|
|
|
|
|
|
bool Link_side::is_client() const
|
|
{
|
|
return this == &_link.client();
|
|
}
|
|
|
|
|
|
/********************
|
|
** Link_side_tree **
|
|
********************/
|
|
|
|
Link_side const &Link_side_tree::find_by_id(Link_side_id const &id) const
|
|
{
|
|
Link_side *const link_side = first();
|
|
if (!link_side) {
|
|
throw No_match(); }
|
|
|
|
return link_side->find_by_id(id);
|
|
}
|
|
|
|
|
|
/**********
|
|
** Link **
|
|
**********/
|
|
|
|
void Link::print(Output &output) const
|
|
{
|
|
Genode::print(output, "CLN ", _client, " SRV ", _server);
|
|
}
|
|
|
|
|
|
Link::Link(Interface &cln_interface,
|
|
Link_side_id const &cln_id,
|
|
Pointer<Port_allocator_guard> srv_port_alloc,
|
|
Domain &srv_domain,
|
|
Link_side_id const &srv_id,
|
|
Timer::Connection &timer,
|
|
Configuration &config,
|
|
L3_protocol const protocol,
|
|
Microseconds const dissolve_timeout)
|
|
:
|
|
_config(config),
|
|
_client_interface(cln_interface),
|
|
_server_port_alloc(srv_port_alloc),
|
|
_dissolve_timeout(timer, *this, &Link::_handle_dissolve_timeout),
|
|
_dissolve_timeout_us(dissolve_timeout),
|
|
_protocol(protocol),
|
|
_client(cln_interface.domain(), cln_id, *this),
|
|
_server(srv_domain, srv_id, *this)
|
|
{
|
|
_client_interface.links(_protocol).insert(this);
|
|
_client.domain().links(_protocol).insert(&_client);
|
|
_server.domain().links(_protocol).insert(&_server);
|
|
_dissolve_timeout.schedule(_dissolve_timeout_us);
|
|
}
|
|
|
|
|
|
void Link::_handle_dissolve_timeout(Duration)
|
|
{
|
|
dissolve();
|
|
_client_interface.links(_protocol).remove(this);
|
|
_client_interface.dissolved_links(_protocol).insert(this);
|
|
}
|
|
|
|
|
|
void Link::dissolve()
|
|
{
|
|
_client.domain().links(_protocol).remove(&_client);
|
|
_server.domain().links(_protocol).remove(&_server);
|
|
if (_config().verbose()) {
|
|
log("Dissolve ", l3_protocol_name(_protocol), " link: ", *this); }
|
|
|
|
try {
|
|
if (_config().verbose()) {
|
|
log("Free ", l3_protocol_name(_protocol),
|
|
" port ", _server.dst_port(),
|
|
" at ", _server.domain(),
|
|
" that was used by ", _client.domain());
|
|
}
|
|
_server_port_alloc().free(_server.dst_port());
|
|
}
|
|
catch (Pointer<Port_allocator_guard>::Invalid) { }
|
|
}
|
|
|
|
|
|
void Link::handle_config(Domain &cln_domain,
|
|
Domain &srv_domain,
|
|
Pointer<Port_allocator_guard> srv_port_alloc,
|
|
Configuration &config)
|
|
{
|
|
Microseconds dissolve_timeout_us(0);
|
|
switch (_protocol) {
|
|
case L3_protocol::TCP: dissolve_timeout_us = config.tcp_idle_timeout(); break;
|
|
case L3_protocol::UDP: dissolve_timeout_us = config.udp_idle_timeout(); break;
|
|
case L3_protocol::ICMP: dissolve_timeout_us = config.icmp_idle_timeout(); break;
|
|
default: throw Interface::Bad_transport_protocol();
|
|
}
|
|
_dissolve_timeout_us = dissolve_timeout_us;
|
|
_dissolve_timeout.schedule(_dissolve_timeout_us);
|
|
|
|
_client.domain().links(_protocol).remove(&_client);
|
|
_server.domain().links(_protocol).remove(&_server);
|
|
|
|
_config = config;
|
|
_client._domain = cln_domain;
|
|
_server._domain = srv_domain;
|
|
_server_port_alloc = srv_port_alloc;
|
|
|
|
cln_domain.links(_protocol).insert(&_client);
|
|
srv_domain.links(_protocol).insert(&_server);
|
|
|
|
if (config.verbose()) {
|
|
log("[", cln_domain, "] update link client: ", _client);
|
|
log("[", srv_domain, "] update link server: ", _server);
|
|
}
|
|
}
|
|
|
|
|
|
/**************
|
|
** Tcp_link **
|
|
**************/
|
|
|
|
Tcp_link::Tcp_link(Interface &cln_interface,
|
|
Link_side_id const &cln_id,
|
|
Pointer<Port_allocator_guard> srv_port_alloc,
|
|
Domain &srv_domain,
|
|
Link_side_id const &srv_id,
|
|
Timer::Connection &timer,
|
|
Configuration &config,
|
|
L3_protocol const protocol)
|
|
:
|
|
Link(cln_interface, cln_id, srv_port_alloc, srv_domain, srv_id, timer,
|
|
config, protocol, config.tcp_idle_timeout())
|
|
{ }
|
|
|
|
|
|
void Tcp_link::_tcp_packet(Tcp_packet &tcp,
|
|
Peer &sender,
|
|
Peer &receiver)
|
|
{
|
|
if (_state == State::CLOSED) {
|
|
return; }
|
|
|
|
if (tcp.rst()) {
|
|
_state = State::CLOSED;
|
|
} else {
|
|
if (tcp.fin()) {
|
|
sender.fin = true;
|
|
_state = State::CLOSING;
|
|
}
|
|
if (receiver.fin && tcp.ack()) {
|
|
receiver.fin_acked = true;
|
|
if (sender.fin_acked) {
|
|
_state = State::CLOSED; }
|
|
else {
|
|
_state = State::CLOSING; }
|
|
}
|
|
}
|
|
if (_state == State::OPEN) {
|
|
_packet();
|
|
} else {
|
|
_dissolve_timeout.schedule(
|
|
Microseconds(_config().tcp_max_segm_lifetime().value << 1));
|
|
}
|
|
}
|
|
|
|
|
|
/**************
|
|
** Udp_link **
|
|
**************/
|
|
|
|
Udp_link::Udp_link(Interface &cln_interface,
|
|
Link_side_id const &cln_id,
|
|
Pointer<Port_allocator_guard> srv_port_alloc,
|
|
Domain &srv_domain,
|
|
Link_side_id const &srv_id,
|
|
Timer::Connection &timer,
|
|
Configuration &config,
|
|
L3_protocol const protocol)
|
|
:
|
|
Link(cln_interface, cln_id, srv_port_alloc, srv_domain, srv_id, timer,
|
|
config, protocol, config.udp_idle_timeout())
|
|
{ }
|
|
|
|
|
|
/***************
|
|
** Icmp_link **
|
|
***************/
|
|
|
|
Icmp_link::Icmp_link(Interface &cln_interface,
|
|
Link_side_id const &cln_id,
|
|
Pointer<Port_allocator_guard> srv_port_alloc,
|
|
Domain &srv_domain,
|
|
Link_side_id const &srv_id,
|
|
Timer::Connection &timer,
|
|
Configuration &config,
|
|
L3_protocol const protocol)
|
|
:
|
|
Link(cln_interface, cln_id, srv_port_alloc, srv_domain, srv_id, timer,
|
|
config, protocol, config.icmp_idle_timeout())
|
|
{ }
|