/**
* Copyright (c) 2018 Cornell University.
*
* Author: Ted Yin <[email protected]>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is furnished to do
* so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#ifndef _SALTICIDAE_NETWORK_H
#define _SALTICIDAE_NETWORK_H
#include "salticidae/event.h"
#include "salticidae/netaddr.h"
#include "salticidae/msg.h"
#include "salticidae/conn.h"
namespace salticidae {
template<typename ClassType, typename ReturnType, typename... Args, typename... FArgs>
inline auto handler_bind(ReturnType(ClassType::* f)(Args...), FArgs&&... fargs) {
return std::function<ReturnType(Args...)>(std::bind(f, std::forward<FArgs>(fargs)...));
}
/** Network of nodes who can send async messages. */
template<typename OpcodeType>
class MsgNetwork: public ConnPool {
public:
using Msg = MsgBase<OpcodeType>;
/* match lambdas */
template<typename T>
struct callback_traits:
public callback_traits<decltype(&T::operator())> {};
/* match plain functions */
template<typename ReturnType, typename MsgType, typename ConnType>
struct callback_traits<ReturnType(MsgType, ConnType)> {
using ret_type = ReturnType;
using conn_type = ConnType;
using msg_type = typename std::remove_reference<MsgType>::type;
};
/* match function pointers */
template<typename ReturnType, typename... Args>
struct callback_traits<ReturnType(*)(Args...)>:
public callback_traits<ReturnType(Args...)> {};
/* match const member functions */
template<typename ClassType, typename ReturnType, typename... Args>
struct callback_traits<ReturnType(ClassType::*)(Args...) const>:
public callback_traits<ReturnType(Args...)> {};
/* match member functions */
template<typename ClassType, typename ReturnType, typename... Args>
struct callback_traits<ReturnType(ClassType::*)(Args...)>:
public callback_traits<ReturnType(Args...)> {};
class Conn: public ConnPool::Conn {
friend MsgNetwork;
enum MsgState {
HEADER,
PAYLOAD
};
Msg msg;
MsgState msg_state;
MsgNetwork *get_net() {
return static_cast<MsgNetwork *>(get_pool());
}
protected:
#ifdef SALTICIDAE_MSG_STAT
mutable size_t nsent;
mutable size_t nrecv;
#endif
public:
Conn(): msg_state(HEADER)
#ifdef SALTICIDAE_MSG_STAT
, nsent(0), nrecv(0)
#endif
{}
#ifdef SALTICIDAE_MSG_STAT
size_t get_nsent() const { return nsent; }
size_t get_nrecv() const { return nrecv; }
void clear_nsent() const { nsent = 0; }
void clear_nrecv() const { nrecv = 0; }
#endif
protected:
void on_read() override;
void on_setup() override {}
void on_teardown() override {}
};
using conn_t = RcObj<Conn>;
#ifdef SALTICIDAE_MSG_STAT
class msg_stat_by_opcode_t:
public std::unordered_map<typename Msg::opcode_t,
std::pair<uint32_t, size_t>> {
public:
void add(const Msg &msg) {
auto &p = this->operator[](msg.get_opcode());
p.first++;
p.second += msg.get_length();
}
};
#endif
private:
std::unordered_map<
typename Msg::opcode_t,
std::function<void(const Msg &msg, conn_t conn)>> handler_map;
protected:
#ifdef SALTICIDAE_MSG_STAT
mutable msg_stat_by_opcode_t sent_by_opcode;
mutable msg_stat_by_opcode_t recv_by_opcode;
#endif
ConnPool::Conn *create_conn() override { return new Conn(); }
public:
MsgNetwork(const EventContext &ec,
int max_listen_backlog,
double conn_server_timeout,
size_t seg_buff_size):
ConnPool(ec, max_listen_backlog,
conn_server_timeout,
seg_buff_size) {}
template<typename Func>
typename std::enable_if<std::is_constructible<
typename callback_traits<Func>::msg_type, DataStream &&>::value>::type
reg_handler(Func handler) {
using callback_t = callback_traits<Func>;
handler_map[callback_t::msg_type::opcode] = [handler](const Msg &msg, conn_t conn) {
handler(typename callback_t::msg_type(msg.get_payload()),
static_pointer_cast<typename callback_t::conn_type::type>(conn));
};
}
template<typename MsgType>
void send_msg(const MsgType &msg, conn_t conn);
using ConnPool::listen;
#ifdef SALTICIDAE_MSG_STAT
msg_stat_by_opcode_t &get_sent_by_opcode() const {
return sent_by_opcode;
}
msg_stat_by_opcode_t &get_recv_by_opcode() const {
return recv_by_opcode;
}
#endif
conn_t connect(const NetAddr &addr) {
return static_pointer_cast<Conn>(ConnPool::connect(addr));
}
};
/** Simple network that handles client-server requests. */
template<typename OpcodeType>
class ClientNetwork: public MsgNetwork<OpcodeType> {
using MsgNet = MsgNetwork<OpcodeType>;
using Msg = typename MsgNet::Msg;
std::unordered_map<NetAddr, typename MsgNet::conn_t> addr2conn;
public:
class Conn: public MsgNet::Conn {
friend ClientNetwork;
ClientNetwork *get_net() {
return static_cast<ClientNetwork *>(ConnPool::Conn::get_pool());
}
public:
Conn() = default;
protected:
void on_setup() override;
void on_teardown() override;
};
using conn_t = RcObj<Conn>;
protected:
ConnPool::Conn *create_conn() override { return new Conn(); }
public:
ClientNetwork(const EventContext &ec,
int max_listen_backlog = 10,
double conn_server_timeout = 0,
size_t seg_buff_size = 4096):
MsgNet(ec, max_listen_backlog,
conn_server_timeout,
seg_buff_size) {}
template<typename MsgType>
void send_msg(const MsgType &msg, const NetAddr &addr);
conn_t connect(const NetAddr &addr) = delete;
};
class PeerNetworkError: public SalticidaeError {
using SalticidaeError::SalticidaeError;
};
/** Peer-to-peer network where any two nodes could hold a bi-diretional message
* channel, established by either side. */
template<typename OpcodeType = uint8_t,
OpcodeType OPCODE_PING = 0xf0,
OpcodeType OPCODE_PONG = 0xf1>
class PeerNetwork: public MsgNetwork<OpcodeType> {
using MsgNet = MsgNetwork<OpcodeType>;
using Msg = typename MsgNet::Msg;
public:
enum IdentityMode {
IP_BASED,
IP_PORT_BASED
};
class Conn: public MsgNet::Conn {
friend PeerNetwork;
NetAddr peer_id;
Event ev_timeout;
PeerNetwork *get_net() {
return static_cast<PeerNetwork *>(ConnPool::Conn::get_pool());
}
public:
Conn() = default;
const NetAddr &get_peer() { return peer_id; }
protected:
void on_close() override {
ev_timeout.clear();
MsgNet::Conn::on_close();
}
void on_setup() override;
void on_teardown() override;
};
using conn_t = RcObj<Conn>;
private:
struct Peer {
/** connection addr, may be different due to passive mode */
NetAddr addr;
/** the underlying connection, may be invalid when connected = false */
conn_t conn;
Event ev_ping_timer;
Event ev_retry_timer;
bool ping_timer_ok;
bool pong_msg_ok;
bool connected;
Peer() = delete;
Peer(NetAddr addr, conn_t conn, const EventContext &ec):
addr(addr), conn(conn),
ev_ping_timer(
Event(ec, -1, 0, std::bind(&Peer::ping_timer, this, _1, _2))),
connected(false) {}
~Peer() {}
Peer &operator=(const Peer &) = delete;
Peer(const Peer &) = delete;
void ping_timer(evutil_socket_t, short);
void reset_ping_timer();
void send_ping();
void clear_all_events() {
if (ev_ping_timer)
ev_ping_timer.del();
}
void reset_conn(conn_t conn);
};
std::unordered_map <NetAddr, BoxObj<Peer>> id2peer;
std::vector<NetAddr> peer_list;
IdentityMode id_mode;
double retry_conn_delay;
double ping_period;
double conn_timeout;
uint16_t listen_port;
struct MsgPing {
static const OpcodeType opcode;
DataStream serialized;
uint16_t port;
MsgPing(uint16_t port) {
serialized << htole(port);
}
MsgPing(DataStream &&s) {
s >> port;
port = letoh(port);
}
};
struct MsgPong {
static const OpcodeType opcode;
DataStream serialized;
uint16_t port;
MsgPong(uint16_t port) {
serialized << htole(port);
}
MsgPong(DataStream &&s) {
s >> port;
port = letoh(port);
}
};
void msg_ping(MsgPing &&msg, conn_t conn);
void msg_pong(MsgPong &&msg, conn_t conn);
void reset_conn_timeout(conn_t conn);
bool check_new_conn(conn_t conn, uint16_t port);
void start_active_conn(const NetAddr &paddr);
protected:
ConnPool::Conn *create_conn() override { return new Conn(); }
virtual double gen_conn_timeout() {
return gen_rand_timeout(retry_conn_delay);
}
public:
PeerNetwork(const EventContext &ec,
int max_listen_backlog = 10,
double retry_conn_delay = 2,
double conn_server_timeout = 2,
size_t seg_buff_size = 4096,
double ping_period = 30,
double conn_timeout = 180,
IdentityMode id_mode = IP_PORT_BASED):
MsgNet(ec, max_listen_backlog,
conn_server_timeout,
seg_buff_size),
id_mode(id_mode),
retry_conn_delay(retry_conn_delay),
ping_period(ping_period),
conn_timeout(conn_timeout) {}
void add_peer(const NetAddr &paddr);
const conn_t get_peer_conn(const NetAddr &paddr) const;
template<typename MsgType>
void send_msg(const MsgType &msg, const Peer *peer);
template<typename MsgType>
void send_msg(const MsgType &msg, const NetAddr &paddr);
void listen(NetAddr listen_addr);
bool has_peer(const NetAddr &paddr) const;
const std::vector<NetAddr> &all_peers() const;
conn_t connect(const NetAddr &addr) {
return static_pointer_cast<Conn>(ConnPool::connect(addr));
}
};
template<typename OpcodeType>
void MsgNetwork<OpcodeType>::Conn::on_read() {
auto &recv_buffer = read();
auto mn = get_net();
while (get_fd() != -1)
{
if (msg_state == Conn::HEADER)
{
if (recv_buffer.size() < Msg::header_size) break;
/* new header available */
bytearray_t data = recv_buffer.pop(Msg::header_size);
msg = Msg(data.data());
msg_state = Conn::PAYLOAD;
}
if (msg_state == Conn::PAYLOAD)
{
size_t len = msg.get_length();
if (recv_buffer.size() < len) break;
/* new payload available */
bytearray_t data = recv_buffer.pop(len);
msg.set_payload(std::move(data));
msg_state = Conn::HEADER;
if (!msg.verify_checksum())
{
SALTICIDAE_LOG_WARN("checksums do not match, dropping the message");
return;
}
auto it = mn->handler_map.find(msg.get_opcode());
if (it == mn->handler_map.end())
SALTICIDAE_LOG_WARN("unknown opcode: %s",
get_hex(msg.get_opcode()).c_str());
else /* call the handler */
{
SALTICIDAE_LOG_DEBUG("got message %s from %s",
std::string(msg).c_str(),
std::string(*this).c_str());
it->second(msg, static_pointer_cast<Conn>(self()));
#ifdef SALTICIDAE_MSG_STAT
nrecv++;
mn->recv_by_opcode.add(msg);
#endif
}
}
}
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::Peer::reset_conn(conn_t new_conn) {
if (conn != new_conn)
{
if (conn)
{
SALTICIDAE_LOG_DEBUG("moving send buffer");
new_conn->move_send_buffer(conn);
SALTICIDAE_LOG_INFO("terminating old connection %s", std::string(*conn).c_str());
conn->terminate();
}
addr = new_conn->get_addr();
conn = new_conn;
}
clear_all_events();
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::Conn::on_setup() {
auto pn = get_net();
assert(!ev_timeout);
ev_timeout = Event(pn->ec, -1, 0, [this](evutil_socket_t, short) {
SALTICIDAE_LOG_INFO("peer ping-pong timeout");
this->terminate();
});
/* the initial ping-pong to set up the connection */
auto conn = static_pointer_cast<Conn>(this->self());
pn->reset_conn_timeout(conn);
pn->MsgNet::send_msg(MsgPing(pn->listen_port), conn);
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::Conn::on_teardown() {
auto pn = get_net();
auto it = pn->id2peer.find(peer_id);
if (it == pn->id2peer.end()) return;
auto p = it->second.get();
if (this != p->conn.get()) return;
p->ev_ping_timer.del();
p->connected = false;
p->conn = nullptr;
SALTICIDAE_LOG_INFO("connection lost %s for %s",
std::string(*this).c_str(),
std::string(peer_id).c_str());
p->ev_retry_timer = Event(pn->ec, -1, 0,
[pn, peer_id = this->peer_id](evutil_socket_t, short) {
pn->start_active_conn(peer_id);
});
p->ev_retry_timer.add_with_timeout(pn->gen_conn_timeout());
}
template<typename O, O _, O __>
bool PeerNetwork<O, _, __>::check_new_conn(conn_t conn, uint16_t port) {
if (conn->peer_id.is_null())
{ /* passive connections can eventually have ids after getting the port
number in IP_BASED_PORT mode */
assert(id_mode == IP_PORT_BASED);
conn->peer_id.ip = conn->get_addr().ip;
conn->peer_id.port = port;
}
auto p = id2peer.find(conn->peer_id)->second.get();
if (p->connected)
{
if (conn != p->conn)
{
conn->terminate();
return true;
}
return false;
}
p->reset_conn(conn);
p->connected = true;
p->reset_ping_timer();
p->send_ping();
if (p->connected)
SALTICIDAE_LOG_INFO("PeerNetwork: established connection with %s via %s",
std::string(conn->peer_id).c_str(), std::string(*conn).c_str());
return false;
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::msg_ping(MsgPing &&msg, conn_t conn_) {
auto conn = static_pointer_cast<Conn>(conn_);
uint16_t port = msg.port;
SALTICIDAE_LOG_INFO("ping from %s, port %u", std::string(*conn).c_str(), ntohs(port));
if (check_new_conn(conn, port)) return;
auto p = id2peer.find(conn->peer_id)->second.get();
send_msg(MsgPong(this->listen_port), p);
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::msg_pong(MsgPong &&msg, conn_t conn_) {
auto conn = static_pointer_cast<Conn>(conn_);
auto it = id2peer.find(conn->peer_id);
if (it == id2peer.end())
{
SALTICIDAE_LOG_WARN("pong message discarded");
return;
}
auto p = it->second.get();
uint16_t port = msg.port;
if (check_new_conn(conn, port)) return;
p->pong_msg_ok = true;
if (p->ping_timer_ok)
{
p->reset_ping_timer();
p->send_ping();
}
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::listen(NetAddr listen_addr) {
MsgNet::listen(listen_addr);
listen_port = listen_addr.port;
this->reg_handler(handler_bind(&PeerNetwork::msg_ping, this, _1, _2));
this->reg_handler(handler_bind(&PeerNetwork::msg_pong, this, _1, _2));
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::start_active_conn(const NetAddr &addr) {
auto p = id2peer.find(addr)->second.get();
if (p->connected) return;
auto conn = static_pointer_cast<Conn>(connect(addr));
assert(p->conn == nullptr);
p->conn = conn;
conn->peer_id = addr;
if (id_mode == IP_BASED)
conn->peer_id.port = 0;
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::add_peer(const NetAddr &addr) {
auto it = id2peer.find(addr);
if (it != id2peer.end())
throw PeerNetworkError("peer already exists");
id2peer.insert(std::make_pair(addr, new Peer(addr, nullptr, this->ec)));
peer_list.push_back(addr);
start_active_conn(addr);
}
template<typename O, O _, O __>
const typename PeerNetwork<O, _, __>::conn_t
PeerNetwork<O, _, __>::get_peer_conn(const NetAddr &paddr) const {
auto it = id2peer.find(paddr);
if (it == id2peer.end())
throw PeerNetworkError("peer does not exist");
return it->second->conn;
}
template<typename O, O _, O __>
bool PeerNetwork<O, _, __>::has_peer(const NetAddr &paddr) const {
return id2peer.count(paddr);
}
template<typename OpcodeType>
template<typename MsgType>
void MsgNetwork<OpcodeType>::send_msg(const MsgType &_msg, conn_t conn) {
Msg msg(_msg);
bytearray_t msg_data = msg.serialize();
SALTICIDAE_LOG_DEBUG("wrote message %s to %s",
std::string(msg).c_str(),
std::string(*conn).c_str());
conn->write(std::move(msg_data));
#ifdef SALTICIDAE_MSG_STAT
conn->nsent++;
sent_by_opcode.add(msg);
#endif
}
template<typename O, O _, O __>
template<typename MsgType>
void PeerNetwork<O, _, __>::send_msg(const MsgType &msg, const Peer *peer) {
if (peer->connected)
MsgNet::send_msg(msg, peer->conn);
else
SALTICIDAE_LOG_DEBUG("dropped");
}
template<typename O, O _, O __>
template<typename MsgType>
void PeerNetwork<O, _, __>::send_msg(const MsgType &msg, const NetAddr &addr) {
auto it = id2peer.find(addr);
if (it == id2peer.end())
{
SALTICIDAE_LOG_ERROR("sending to non-existing peer: %s",
std::string(addr).c_str());
throw PeerNetworkError("peer does not exist");
}
send_msg(msg, it->second.get());
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::Peer::reset_ping_timer() {
assert(ev_ping_timer);
ev_ping_timer.del();
ev_ping_timer.add_with_timeout(
gen_rand_timeout(conn->get_net()->ping_period));
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::reset_conn_timeout(conn_t conn) {
assert(conn->ev_timeout);
conn->ev_timeout.del();
conn->ev_timeout.add_with_timeout(conn_timeout);
SALTICIDAE_LOG_INFO("reset timeout %.2f", conn_timeout);
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::Peer::send_ping() {
auto pn = conn->get_net();
ping_timer_ok = false;
pong_msg_ok = false;
pn->reset_conn_timeout(conn);
pn->send_msg(MsgPing(pn->listen_port), this);
}
template<typename O, O _, O __>
void PeerNetwork<O, _, __>::Peer::ping_timer(evutil_socket_t, short) {
ping_timer_ok = true;
if (pong_msg_ok)
{
reset_ping_timer();
send_ping();
}
}
template<typename O, O _, O __>
const std::vector<NetAddr> &PeerNetwork<O, _, __>::all_peers() const {
return peer_list;
}
template<typename OpcodeType>
void ClientNetwork<OpcodeType>::Conn::on_setup() {
assert(this->get_mode() == Conn::PASSIVE);
const auto &addr = this->get_addr();
auto cn = get_net();
cn->addr2conn.erase(addr);
cn->addr2conn.insert(
std::make_pair(addr,
static_pointer_cast<Conn>(this->self())));
}
template<typename OpcodeType>
void ClientNetwork<OpcodeType>::Conn::on_teardown() {
assert(this->get_mode() == Conn::PASSIVE);
get_net()->addr2conn.erase(this->get_addr());
}
template<typename OpcodeType>
template<typename MsgType>
void ClientNetwork<OpcodeType>::send_msg(const MsgType &msg, const NetAddr &addr) {
auto it = addr2conn.find(addr);
if (it == addr2conn.end()) return;
MsgNet::send_msg(msg, it->second);
}
template<typename O, O OPCODE_PING, O _>
const O PeerNetwork<O, OPCODE_PING, _>::MsgPing::opcode = OPCODE_PING;
template<typename O, O _, O OPCODE_PONG>
const O PeerNetwork<O, _, OPCODE_PONG>::MsgPong::opcode = OPCODE_PONG;
}
#endif