lokinet/llarp/link/link_manager.hpp
dr7ana 61718464ae zero cost exception handling my ass
- rework bootstrap loading to move all logic into BootstrapList object
- ability to parse lists and dicts of bootstraps implemented
- netid parsing refers to the correct fallback
- cross your fingers boys here we go
2024-01-31 07:54:12 -08:00

480 lines
14 KiB
C++

#pragma once
#include "connection.hpp"
#include <llarp/constants/path.hpp>
#include <llarp/crypto/crypto.hpp>
#include <llarp/messages/common.hpp>
#include <llarp/path/transit_hop.hpp>
#include <llarp/router_contact.hpp>
#include <llarp/util/compare_ptr.hpp>
#include <llarp/util/decaying_hashset.hpp>
#include <llarp/util/logging.hpp>
#include <llarp/util/priority_queue.hpp>
#include <quic.hpp>
#include <atomic>
#include <set>
#include <unordered_map>
namespace
{
static auto quic_cat = llarp::log::Cat("lokinet.quic");
} // namespace
namespace llarp
{
struct LinkManager;
class NodeDB;
using conn_open_hook = oxen::quic::connection_established_callback;
using conn_closed_hook = oxen::quic::connection_closed_callback;
using stream_open_hook = oxen::quic::stream_open_callback;
using stream_closed_hook = oxen::quic::stream_close_callback;
using keep_alive = oxen::quic::opt::keep_alive;
using inbound_alpns = oxen::quic::opt::inbound_alpns;
using outbound_alpns = oxen::quic::opt::outbound_alpns;
inline const keep_alive ROUTER_KEEP_ALIVE{10s};
inline const keep_alive CLIENT_KEEP_ALIVE{0s};
namespace alpns
{
inline const auto SN_ALPNS = "SERVICE_NODE"_us;
inline const auto C_ALPNS = "CLIENT"_us;
inline const inbound_alpns SERVICE_INBOUND{{SN_ALPNS, C_ALPNS}};
inline const outbound_alpns SERVICE_OUTBOUND{{SN_ALPNS}};
inline const inbound_alpns CLIENT_INBOUND{};
inline const outbound_alpns CLIENT_OUTBOUND{{C_ALPNS}};
} // namespace alpns
namespace link
{
struct Connection;
struct Endpoint
{
Endpoint(std::shared_ptr<oxen::quic::Endpoint> ep, LinkManager& lm);
std::shared_ptr<oxen::quic::Endpoint> endpoint;
LinkManager& link_manager;
/** Connection containers:
- service_conns: holds all connections where the remote (from the perspective
of the local lokinet instance) is a service node. This means all relay to
relay connections are held here; clients will also hold their connections to
relays here as well
- client_conns: holds all connections wehre the remote is a client. This is only
used by service nodes to store their client connections
*/
std::unordered_map<RouterID, std::shared_ptr<link::Connection>> service_conns;
std::unordered_map<RouterID, std::shared_ptr<link::Connection>> client_conns;
std::shared_ptr<link::Connection>
get_conn(const RouterID&) const;
std::shared_ptr<link::Connection>
get_service_conn(const RouterID&) const;
bool
have_conn(const RouterID& remote) const;
bool
have_client_conn(const RouterID& remote) const;
bool
have_service_conn(const RouterID& remote) const;
std::pair<size_t, size_t>
num_in_out() const;
size_t
num_connected(bool clients_only) const;
template <typename... Opt>
bool
establish_connection(
const oxen::quic::RemoteAddress& remote, const RemoteRC& rc, Opt&&... opts);
void
for_each_connection(std::function<void(link::Connection&)> func);
void
close_connection(RouterID rid);
private:
const bool _is_service_node;
};
} // namespace link
enum class SessionResult
{
Establish,
Timeout,
RouterNotFound,
InvalidRouter,
NoLink,
EstablishFail
};
constexpr std::string_view
ToString(SessionResult sr)
{
return sr == llarp::SessionResult::Establish ? "success"sv
: sr == llarp::SessionResult::Timeout ? "timeout"sv
: sr == llarp::SessionResult::NoLink ? "no link"sv
: sr == llarp::SessionResult::InvalidRouter ? "invalid router"sv
: sr == llarp::SessionResult::RouterNotFound ? "not found"sv
: sr == llarp::SessionResult::EstablishFail ? "establish failed"sv
: "???"sv;
}
template <>
constexpr inline bool IsToStringFormattable<SessionResult> = true;
struct PendingMessage
{
std::string body;
std::optional<std::string> endpoint = std::nullopt;
std::function<void(oxen::quic::message)> func = nullptr;
RouterID rid;
bool is_control = false;
PendingMessage(std::string b) : body{std::move(b)}
{}
PendingMessage(
std::string b, std::string ep, std::function<void(oxen::quic::message)> f = nullptr)
: body{std::move(b)}, endpoint{std::move(ep)}, func{std::move(f)}, is_control{true}
{}
};
using MessageQueue = std::deque<PendingMessage>;
struct Router;
struct LinkManager
{
public:
static std::unique_ptr<LinkManager>
make(Router& r);
bool
send_control_message(
const RouterID& remote,
std::string endpoint,
std::string body,
std::function<void(oxen::quic::message)> = nullptr);
bool
send_data_message(const RouterID& remote, std::string data);
Router&
router() const
{
return _router;
}
private:
explicit LinkManager(Router& r);
bool
send_control_message_impl(
const RouterID& remote,
std::string endpoint,
std::string body,
std::function<void(oxen::quic::message)> = nullptr);
friend struct link::Endpoint;
std::atomic<bool> is_stopping;
// sessions to persist -> timestamp to end persist at
std::unordered_map<RouterID, llarp_time_t> persisting_conns;
// holds any messages we attempt to send while connections are establishing
std::unordered_map<RouterID, MessageQueue> pending_conn_msg_queue;
// when establishing a connection, the rid of the remote is placed here to be cross-
// checked by the tls verification callback
std::map<RouterID, RemoteRC> rids_pending_verification;
// in the interim of verifying an outbound connection and the creation of its link::Connection
// object, we store the rid and rc here
std::map<RouterID, RemoteRC> verified_rids;
util::DecayingHashSet<RouterID> clients{path::DEFAULT_LIFETIME};
std::shared_ptr<NodeDB> node_db;
oxen::quic::Address addr;
Router& _router;
const bool _is_service_node;
// FIXME: Lokinet currently expects to be able to kill all network functionality before
// finishing other shutdown things, including destroying this class, and that is all in
// Network's destructor, so we need to be able to destroy it before this class.
std::unique_ptr<oxen::quic::Network> quic;
std::shared_ptr<oxen::quic::GNUTLSCreds> tls_creds;
link::Endpoint ep;
void
recv_data_message(oxen::quic::dgram_interface& dgi, bstring dgram);
void
recv_control_message(oxen::quic::message msg);
std::shared_ptr<oxen::quic::BTRequestStream>
make_control(oxen::quic::connection_interface& ci, const RouterID& rid);
void
on_inbound_conn(oxen::quic::connection_interface& ci);
void
on_outbound_conn(oxen::quic::connection_interface& ci);
void
on_conn_open(oxen::quic::connection_interface& ci);
void
on_conn_closed(oxen::quic::connection_interface& ci, uint64_t ec);
std::shared_ptr<oxen::quic::Endpoint>
startup_endpoint();
void
register_commands(
std::shared_ptr<oxen::quic::BTRequestStream>& s,
const RouterID& rid,
bool client_only = false);
public:
const link::Endpoint&
endpoint() const
{
return ep;
}
const oxen::quic::Address&
local()
{
return addr;
}
void
gossip_rc(const RouterID& last_sender, const RemoteRC& rc);
void
handle_gossip_rc(oxen::quic::message m);
void
fetch_rcs(
const RouterID& source,
std::string payload,
std::function<void(oxen::quic::message m)> func);
void
handle_fetch_rcs(oxen::quic::message m);
void
fetch_router_ids(
const RouterID& via, std::string payload, std::function<void(oxen::quic::message m)> func);
void
handle_fetch_router_ids(oxen::quic::message m);
void
fetch_bootstrap_rcs(
const RemoteRC& source,
std::string payload,
std::function<void(oxen::quic::message m)> func);
void
handle_fetch_bootstrap_rcs(oxen::quic::message m);
bool
have_connection_to(const RouterID& remote) const;
bool
have_service_connection_to(const RouterID& remote) const;
bool
have_client_connection_to(const RouterID& remote) const;
void
test_reachability(const RouterID& rid, conn_open_hook, conn_closed_hook);
void
connect_to(const RouterID& router, conn_open_hook = nullptr);
void
connect_to(const RemoteRC& rc, conn_open_hook = nullptr, conn_closed_hook = nullptr);
void
close_connection(RouterID rid);
void
stop();
void
set_conn_persist(const RouterID& remote, llarp_time_t until);
std::pair<size_t, size_t>
num_in_out() const;
size_t
get_num_connected(bool clients_only = false) const;
size_t
get_num_connected_clients() const;
bool
is_service_node() const;
void
check_persisting_conns(llarp_time_t now);
util::StatusObject
extract_status() const;
void
init();
void
for_each_connection(std::function<void(link::Connection&)> func);
// Attempts to connect to a number of random routers.
//
// This will try to connect to *up to* num_conns routers, but will not
// check if we already have a connection to any of the random set, as making
// that thread safe would be slow...I think.
void
connect_to_random(int num_conns, bool client_only = false);
/// always maintain this many client connections to other routers
int client_router_connections = 4;
private:
// DHT messages
void
handle_find_name(std::string_view body, std::function<void(std::string)> respond); // relay
void
handle_find_intro(std::string_view body, std::function<void(std::string)> respond); // relay
void
handle_publish_intro(std::string_view body, std::function<void(std::string)> respond); // relay
// Path messages
void
handle_path_build(oxen::quic::message, const RouterID& from); // relay
void handle_path_latency(oxen::quic::message); // relay
void handle_path_transfer(oxen::quic::message); // relay
// Exit messages
void handle_obtain_exit(oxen::quic::message); // relay
void handle_update_exit(oxen::quic::message); // relay
void handle_close_exit(oxen::quic::message); // relay
// Misc
void handle_convo_intro(oxen::quic::message);
// These requests come over a path (as a "path_control" request),
// may or may not need to make a request to another relay,
// then respond (onioned) back along the path.
std::unordered_map<
std::string_view,
void (LinkManager::*)(std::string_view body, std::function<void(std::string)> respond)>
path_requests = {
{"find_name"sv, &LinkManager::handle_find_name},
{"publish_intro"sv, &LinkManager::handle_publish_intro},
{"find_intro"sv, &LinkManager::handle_find_intro}};
// these requests are direct, i.e. not over a path;
// the rest are relay->relay
std::unordered_map<
std::string_view,
void (LinkManager::*)(std::string_view body, std::function<void(std::string)> respond)>
direct_requests = {
{"publish_intro"sv, &LinkManager::handle_publish_intro},
{"find_intro"sv, &LinkManager::handle_find_intro}};
// Path relaying
void
handle_path_control(oxen::quic::message, const RouterID& from);
void
handle_inner_request(
oxen::quic::message m, std::string payload, std::shared_ptr<path::TransitHop> hop);
// DHT responses
void handle_find_name_response(oxen::quic::message);
void handle_find_intro_response(oxen::quic::message);
void handle_publish_intro_response(oxen::quic::message);
// Path responses
void handle_path_latency_response(oxen::quic::message);
void handle_path_transfer_response(oxen::quic::message);
// Exit responses
void handle_obtain_exit_response(oxen::quic::message);
void handle_update_exit_response(oxen::quic::message);
void handle_close_exit_response(oxen::quic::message);
/**
Clients register 0 endpoints
- nobody is making requests to clients
*/
};
namespace link
{
template <typename... Opt>
bool
Endpoint::establish_connection(
const oxen::quic::RemoteAddress& remote, const RemoteRC& rc, Opt&&... opts)
{
try
{
const auto& rid = rc.router_id();
log::critical(logcat, "Establishing connection to RID:{}", rid);
bool is_snode = link_manager.is_service_node();
auto conn_interface = endpoint->connect(
remote,
link_manager.tls_creds,
is_snode ? ROUTER_KEEP_ALIVE : CLIENT_KEEP_ALIVE,
std::forward<Opt>(opts)...);
// add to service conns
auto [itr, b] = service_conns.emplace(rid, nullptr);
auto control_stream = conn_interface->template open_stream<oxen::quic::BTRequestStream>(
[this, rid = rid](oxen::quic::Stream&, uint64_t error_code) {
log::warning(
logcat,
"BTRequestStream closed unexpectedly (ec:{}); closing outbound connection...",
error_code);
close_connection(rid);
});
log::critical(logcat, "Opened BTStream (ID:{})", control_stream->stream_id());
assert(control_stream->stream_id() == 0);
link_manager.register_commands(control_stream, rid);
itr->second = std::make_shared<link::Connection>(conn_interface, control_stream, true);
log::critical(logcat, "Outbound connection to RID:{} added to service conns...", rid);
return true;
}
catch (...)
{
log::error(quic_cat, "Error: failed to establish connection to {}", remote);
return false;
}
}
} // namespace link
} // namespace llarp