nostr-rs-relay/src/server.rs
2022-12-18 13:44:28 -06:00

709 lines
32 KiB
Rust

//! Server process
use crate::close::Close;
use crate::close::CloseCmd;
use crate::config::{Settings, VerifiedUsersMode};
use crate::conn;
use crate::db;
use crate::db::SubmittedEvent;
use crate::error::{Error, Result};
use crate::event::Event;
use crate::event::EventCmd;
use crate::info::RelayInfo;
use crate::nip05;
use crate::notice::Notice;
use crate::subscription::Subscription;
use futures::SinkExt;
use futures::StreamExt;
use governor::{Jitter, Quota, RateLimiter};
use http::header::HeaderMap;
use hyper::header::ACCEPT;
use hyper::service::{make_service_fn, service_fn};
use hyper::upgrade::Upgraded;
use hyper::{
header, server::conn::AddrStream, upgrade, Body, Request, Response, Server, StatusCode,
};
use serde::{Deserialize, Serialize};
use serde_json::json;
use std::collections::HashMap;
use std::convert::Infallible;
use std::net::SocketAddr;
use std::path::Path;
use std::sync::mpsc::Receiver as MpscReceiver;
use std::time::Duration;
use std::time::Instant;
use tokio::runtime::Builder;
use tokio::sync::broadcast::{self, Receiver, Sender};
use tokio::sync::mpsc;
use tokio::sync::oneshot;
use tokio_tungstenite::WebSocketStream;
use tracing::*;
use tungstenite::error::CapacityError::MessageTooLong;
use tungstenite::error::Error as WsError;
use tungstenite::handshake;
use tungstenite::protocol::Message;
use tungstenite::protocol::WebSocketConfig;
/// Handle arbitrary HTTP requests, including for WebSocket upgrades.
async fn handle_web_request(
mut request: Request<Body>,
pool: db::SqlitePool,
settings: Settings,
remote_addr: SocketAddr,
broadcast: Sender<Event>,
event_tx: tokio::sync::mpsc::Sender<SubmittedEvent>,
shutdown: Receiver<()>,
) -> Result<Response<Body>, Infallible> {
match (
request.uri().path(),
request.headers().contains_key(header::UPGRADE),
) {
// Request for / as websocket
("/", true) => {
trace!("websocket with upgrade request");
//assume request is a handshake, so create the handshake response
let response = match handshake::server::create_response_with_body(&request, || {
Body::empty()
}) {
Ok(response) => {
//in case the handshake response creation succeeds,
//spawn a task to handle the websocket connection
tokio::spawn(async move {
//using the hyper feature of upgrading a connection
match upgrade::on(&mut request).await {
//if successfully upgraded
Ok(upgraded) => {
// set WebSocket configuration options
let config = WebSocketConfig {
max_message_size: settings.limits.max_ws_message_bytes,
max_frame_size: settings.limits.max_ws_frame_bytes,
..Default::default()
};
//create a websocket stream from the upgraded object
let ws_stream = WebSocketStream::from_raw_socket(
//pass the upgraded object
//as the base layer stream of the Websocket
upgraded,
tokio_tungstenite::tungstenite::protocol::Role::Server,
Some(config),
)
.await;
let user_agent = get_header_string("user-agent", request.headers());
// determine the remote IP from headers if the exist
let header_ip = settings
.network
.remote_ip_header
.as_ref()
.and_then(|x| get_header_string(x, request.headers()));
// use the socket addr as a backup
let remote_ip =
header_ip.unwrap_or_else(|| remote_addr.ip().to_string());
let client_info = ClientInfo {
remote_ip,
user_agent,
};
// spawn a nostr server with our websocket
tokio::spawn(nostr_server(
pool,
client_info,
settings,
ws_stream,
broadcast,
event_tx,
shutdown,
));
}
// todo: trace, don't print...
Err(e) => println!(
"error when trying to upgrade connection \
from address {} to websocket connection. \
Error is: {}",
remote_addr, e
),
}
});
//return the response to the handshake request
response
}
Err(error) => {
warn!("websocket response failed");
let mut res =
Response::new(Body::from(format!("Failed to create websocket: {}", error)));
*res.status_mut() = StatusCode::BAD_REQUEST;
return Ok(res);
}
};
Ok::<_, Infallible>(response)
}
// Request for Relay info
("/", false) => {
// handle request at root with no upgrade header
// Check if this is a nostr server info request
let accept_header = &request.headers().get(ACCEPT);
// check if application/nostr+json is included
if let Some(media_types) = accept_header {
if let Ok(mt_str) = media_types.to_str() {
if mt_str.contains("application/nostr+json") {
// build a relay info response
debug!("Responding to server info request");
let rinfo = RelayInfo::from(settings.info);
let b = Body::from(serde_json::to_string_pretty(&rinfo).unwrap());
return Ok(Response::builder()
.status(200)
.header("Content-Type", "application/nostr+json")
.header("Access-Control-Allow-Origin", "*")
.body(b)
.unwrap());
}
}
}
Ok(Response::builder()
.status(200)
.header("Content-Type", "text/plain")
.body(Body::from("Please use a Nostr client to connect."))
.unwrap())
}
(_, _) => {
//handle any other url
Ok(Response::builder()
.status(StatusCode::NOT_FOUND)
.body(Body::from("Nothing here."))
.unwrap())
}
}
}
fn get_header_string(header: &str, headers: &HeaderMap) -> Option<String> {
headers
.get(header)
.and_then(|x| x.to_str().ok().map(|x| x.to_string()))
}
// return on a control-c or internally requested shutdown signal
async fn ctrl_c_or_signal(mut shutdown_signal: Receiver<()>) {
let mut term_signal = tokio::signal::unix::signal(tokio::signal::unix::SignalKind::terminate())
.expect("could not define signal");
loop {
tokio::select! {
_ = shutdown_signal.recv() => {
info!("Shutting down webserver as requested");
// server shutting down, exit loop
break;
},
_ = tokio::signal::ctrl_c() => {
info!("Shutting down webserver due to SIGINT");
break;
},
_ = term_signal.recv() => {
info!("Shutting down webserver due to SIGTERM");
break;
},
}
}
}
/// Start running a Nostr relay server.
pub fn start_server(settings: Settings, shutdown_rx: MpscReceiver<()>) -> Result<(), Error> {
trace!("Config: {:?}", settings);
// do some config validation.
if !Path::new(&settings.database.data_directory).is_dir() {
error!("Database directory does not exist");
return Err(Error::DatabaseDirError);
}
let addr = format!(
"{}:{}",
settings.network.address.trim(),
settings.network.port
);
let socket_addr = addr.parse().expect("listening address not valid");
// address whitelisting settings
if let Some(addr_whitelist) = &settings.authorization.pubkey_whitelist {
info!(
"Event publishing restricted to {} pubkey(s)",
addr_whitelist.len()
);
}
// check if NIP-05 enforced user verification is on
if settings.verified_users.is_active() {
info!(
"NIP-05 user verification mode:{:?}",
settings.verified_users.mode
);
if let Some(d) = settings.verified_users.verify_update_duration() {
info!("NIP-05 check user verification every: {:?}", d);
}
if let Some(d) = settings.verified_users.verify_expiration_duration() {
info!("NIP-05 user verification expires after: {:?}", d);
}
if let Some(wl) = &settings.verified_users.domain_whitelist {
info!("NIP-05 domain whitelist: {:?}", wl);
}
if let Some(bl) = &settings.verified_users.domain_blacklist {
info!("NIP-05 domain blacklist: {:?}", bl);
}
}
// configure tokio runtime
let rt = Builder::new_multi_thread()
.enable_all()
.thread_name("tokio-ws")
// limit concurrent SQLite blocking threads
.max_blocking_threads(settings.limits.max_blocking_threads)
.on_thread_start(|| {
debug!("started new thread");
})
.on_thread_stop(|| {
debug!("stopping thread");
})
.build()
.unwrap();
// start tokio
rt.block_on(async {
let broadcast_buffer_limit = settings.limits.broadcast_buffer;
let persist_buffer_limit = settings.limits.event_persist_buffer;
let verified_users_active = settings.verified_users.is_active();
let db_min_conn = settings.database.min_conn;
let db_max_conn = settings.database.max_conn;
let settings = settings.clone();
info!("listening on: {}", socket_addr);
// all client-submitted valid events are broadcast to every
// other client on this channel. This should be large enough
// to accomodate slower readers (messages are dropped if
// clients can not keep up).
let (bcast_tx, _) = broadcast::channel::<Event>(broadcast_buffer_limit);
// validated events that need to be persisted are sent to the
// database on via this channel.
let (event_tx, event_rx) = mpsc::channel::<SubmittedEvent>(persist_buffer_limit);
// establish a channel for letting all threads now about a
// requested server shutdown.
let (invoke_shutdown, shutdown_listen) = broadcast::channel::<()>(1);
// create a channel for sending any new metadata event. These
// will get processed relatively slowly (a potentially
// multi-second blocking HTTP call) on a single thread, so we
// buffer requests on the channel. No harm in dropping events
// here, since we are protecting against DoS. This can make
// it difficult to setup initial metadata in bulk, since
// overwhelming this will drop events and won't register
// metadata events.
let (metadata_tx, metadata_rx) = broadcast::channel::<Event>(4096);
// start the database writer thread. Give it a channel for
// writing events, and for publishing events that have been
// written (to all connected clients).
db::db_writer(
settings.clone(),
event_rx,
bcast_tx.clone(),
metadata_tx.clone(),
shutdown_listen,
)
.await;
info!("db writer created");
// create a nip-05 verifier thread; if enabled.
if settings.verified_users.mode != VerifiedUsersMode::Disabled {
let verifier_opt =
nip05::Verifier::new(metadata_rx, bcast_tx.clone(), settings.clone());
if let Ok(mut v) = verifier_opt {
if verified_users_active {
tokio::task::spawn(async move {
info!("starting up NIP-05 verifier...");
v.run().await;
});
}
}
}
// listen for (external to tokio) shutdown request
let controlled_shutdown = invoke_shutdown.clone();
tokio::spawn(async move {
info!("control message listener started");
match shutdown_rx.recv() {
Ok(()) => {
info!("control message requesting shutdown");
controlled_shutdown.send(()).ok();
}
Err(std::sync::mpsc::RecvError) => {
// FIXME: spurious error on startup?
debug!("shutdown requestor is disconnected");
}
};
});
// listen for ctrl-c interruupts
let ctrl_c_shutdown = invoke_shutdown.clone();
// listener for webserver shutdown
let webserver_shutdown_listen = invoke_shutdown.subscribe();
tokio::spawn(async move {
tokio::signal::ctrl_c().await.unwrap();
info!("shutting down due to SIGINT (main)");
ctrl_c_shutdown.send(()).ok();
});
// build a connection pool for sqlite connections
let pool = db::build_pool(
"client query",
&settings,
rusqlite::OpenFlags::SQLITE_OPEN_READ_ONLY
| rusqlite::OpenFlags::SQLITE_OPEN_SHARED_CACHE,
db_min_conn,
db_max_conn,
true,
);
// A `Service` is needed for every connection, so this
// creates one from our `handle_request` function.
let make_svc = make_service_fn(|conn: &AddrStream| {
let svc_pool = pool.clone();
let remote_addr = conn.remote_addr();
let bcast = bcast_tx.clone();
let event = event_tx.clone();
let stop = invoke_shutdown.clone();
let settings = settings.clone();
async move {
// service_fn converts our function into a `Service`
Ok::<_, Infallible>(service_fn(move |request: Request<Body>| {
handle_web_request(
request,
svc_pool.clone(),
settings.clone(),
remote_addr,
bcast.clone(),
event.clone(),
stop.subscribe(),
)
}))
}
});
let server = Server::bind(&socket_addr)
.serve(make_svc)
.with_graceful_shutdown(ctrl_c_or_signal(webserver_shutdown_listen));
// run hyper in this thread. This is why the thread does not return.
if let Err(e) = server.await {
eprintln!("server error: {}", e);
}
});
Ok(())
}
/// Nostr protocol messages from a client
#[derive(Deserialize, Serialize, Clone, PartialEq, Eq, Debug)]
#[serde(untagged)]
pub enum NostrMessage {
/// An `EVENT` message
EventMsg(EventCmd),
/// A `REQ` message
SubMsg(Subscription),
/// A `CLOSE` message
CloseMsg(CloseCmd),
}
/// Convert Message to NostrMessage
fn convert_to_msg(msg: String, max_bytes: Option<usize>) -> Result<NostrMessage> {
let parsed_res: Result<NostrMessage> = serde_json::from_str(&msg).map_err(|e| e.into());
match parsed_res {
Ok(m) => {
if let NostrMessage::EventMsg(_) = m {
if let Some(max_size) = max_bytes {
// check length, ensure that some max size is set.
if msg.len() > max_size && max_size > 0 {
return Err(Error::EventMaxLengthError(msg.len()));
}
}
}
Ok(m)
}
Err(e) => {
debug!("proto parse error: {:?}", e);
debug!("parse error on message: {}", msg.trim());
Err(Error::ProtoParseError)
}
}
}
/// Turn a string into a NOTICE message ready to send over a WebSocket
fn make_notice_message(notice: Notice) -> Message {
let json = match notice {
Notice::Message(ref msg) => json!(["NOTICE", msg]),
Notice::EventResult(ref res) => json!(["OK", res.id, res.status.to_bool(), res.msg]),
};
Message::text(json.to_string())
}
struct ClientInfo {
remote_ip: String,
user_agent: Option<String>,
}
/// Handle new client connections. This runs through an event loop
/// for all client communication.
async fn nostr_server(
pool: db::SqlitePool,
client_info: ClientInfo,
settings: Settings,
mut ws_stream: WebSocketStream<Upgraded>,
broadcast: Sender<Event>,
event_tx: mpsc::Sender<SubmittedEvent>,
mut shutdown: Receiver<()>,
) {
// the time this websocket nostr server started
let orig_start = Instant::now();
// get a broadcast channel for clients to communicate on
let mut bcast_rx = broadcast.subscribe();
// Track internal client state
let mut conn = conn::ClientConn::new(client_info.remote_ip);
// subscription creation rate limiting
let mut sub_lim_opt = None;
// 100ms jitter when the rate limiter returns
let jitter = Jitter::up_to(Duration::from_millis(100));
let sub_per_min_setting = settings.limits.subscriptions_per_min;
if let Some(sub_per_min) = sub_per_min_setting {
if sub_per_min > 0 {
trace!("Rate limits for sub creation ({}/min)", sub_per_min);
let quota_time = core::num::NonZeroU32::new(sub_per_min).unwrap();
let quota = Quota::per_minute(quota_time);
sub_lim_opt = Some(RateLimiter::direct(quota));
}
}
// Use the remote IP as the client identifier
let cid = conn.get_client_prefix();
// Create a channel for receiving query results from the database.
// we will send out the tx handle to any query we generate.
// this has capacity for some of the larger requests we see, which
// should allow the DB thread to release the handle earlier.
let (query_tx, mut query_rx) = mpsc::channel::<db::QueryResult>(20000);
// Create channel for receiving NOTICEs
let (notice_tx, mut notice_rx) = mpsc::channel::<Notice>(128);
// last time this client sent data (message, ping, etc.)
let mut last_message_time = Instant::now();
// ping interval (every 5 minutes)
let default_ping_dur = Duration::from_secs(settings.network.ping_interval_seconds.into());
// disconnect after 20 minutes without a ping response or event.
let max_quiet_time = Duration::from_secs(60 * 20);
let start = tokio::time::Instant::now() + default_ping_dur;
let mut ping_interval = tokio::time::interval_at(start, default_ping_dur);
// maintain a hashmap of a oneshot channel for active subscriptions.
// when these subscriptions are cancelled, make a message
// available to the executing query so it knows to stop.
let mut running_queries: HashMap<String, oneshot::Sender<()>> = HashMap::new();
// for stats, keep track of how many events the client published,
// and how many it received from queries.
let mut client_published_event_count: usize = 0;
let mut client_received_event_count: usize = 0;
debug!("new client connection (cid: {}, ip: {:?})", cid, conn.ip());
if let Some(ua) = client_info.user_agent {
debug!("cid: {}, user-agent: {:?}", cid, ua);
}
loop {
tokio::select! {
_ = shutdown.recv() => {
info!("Close connection down due to shutdown, client: {}, ip: {:?}, connected: {:?}", cid, conn.ip(), orig_start.elapsed());
// server shutting down, exit loop
break;
},
_ = ping_interval.tick() => {
// check how long since we talked to client
// if it has been too long, disconnect
if last_message_time.elapsed() > max_quiet_time {
debug!("ending connection due to lack of client ping response");
break;
}
// Send a ping
ws_stream.send(Message::Ping(Vec::new())).await.ok();
},
Some(notice_msg) = notice_rx.recv() => {
ws_stream.send(make_notice_message(notice_msg)).await.ok();
},
Some(query_result) = query_rx.recv() => {
// database informed us of a query result we asked for
let subesc = query_result.sub_id.replace('"', "");
if query_result.event == "EOSE" {
let send_str = format!("[\"EOSE\",\"{}\"]", subesc);
ws_stream.send(Message::Text(send_str)).await.ok();
} else {
client_received_event_count += 1;
// send a result
let send_str = format!("[\"EVENT\",\"{}\",{}]", subesc, &query_result.event);
ws_stream.send(Message::Text(send_str)).await.ok();
}
},
// TODO: consider logging the LaggedRecv error
Ok(global_event) = bcast_rx.recv() => {
// an event has been broadcast to all clients
// first check if there is a subscription for this event.
for (s, sub) in conn.subscriptions() {
if !sub.interested_in_event(&global_event) {
continue;
}
// TODO: serialize at broadcast time, instead of
// once for each consumer.
if let Ok(event_str) = serde_json::to_string(&global_event) {
debug!("sub match for client: {}, sub: {:?}, event: {:?}",
cid, s,
global_event.get_event_id_prefix());
// create an event response and send it
let subesc = s.replace('"', "");
ws_stream.send(Message::Text(format!("[\"EVENT\",\"{}\",{}]", subesc, event_str))).await.ok();
} else {
warn!("could not serialize event: {:?}", global_event.get_event_id_prefix());
}
}
},
ws_next = ws_stream.next() => {
// update most recent message time for client
last_message_time = Instant::now();
// Consume text messages from the client, parse into Nostr messages.
let nostr_msg = match ws_next {
Some(Ok(Message::Text(m))) => {
convert_to_msg(m,settings.limits.max_event_bytes)
},
Some(Ok(Message::Binary(_))) => {
ws_stream.send(
make_notice_message(Notice::message("binary messages are not accepted".into()))).await.ok();
continue;
},
Some(Ok(Message::Ping(_) | Message::Pong(_))) => {
// get a ping/pong, ignore. tungstenite will
// send responses automatically.
continue;
},
Some(Err(WsError::Capacity(MessageTooLong{size, max_size}))) => {
ws_stream.send(
make_notice_message(Notice::message(format!("message too large ({} > {})",size, max_size)))).await.ok();
continue;
},
None |
Some(Ok(Message::Close(_)) |
Err(WsError::AlreadyClosed | WsError::ConnectionClosed |
WsError::Protocol(tungstenite::error::ProtocolError::ResetWithoutClosingHandshake)))
=> {
debug!("websocket close from client (cid: {}, ip: {:?})",cid, conn.ip());
break;
},
Some(Err(WsError::Io(e))) => {
// IO errors are considered fatal
warn!("IO error (cid: {}, ip: {:?}): {:?}", cid, conn.ip(), e);
break;
}
x => {
// default condition on error is to close the client connection
info!("unknown error (cid: {}, ip: {:?}): {:?} (closing conn)", cid, conn.ip(), x);
break;
}
};
// convert ws_next into proto_next
match nostr_msg {
Ok(NostrMessage::EventMsg(ec)) => {
// An EventCmd needs to be validated to be converted into an Event
// handle each type of message
let evid = ec.event_id().to_owned();
let parsed : Result<Event> = Result::<Event>::from(ec);
match parsed {
Ok(e) => {
let id_prefix:String = e.id.chars().take(8).collect();
debug!("successfully parsed/validated event: {:?} (cid: {})", id_prefix, cid);
// check if the event is too far in the future.
if e.is_valid_timestamp(settings.options.reject_future_seconds) {
// Write this to the database.
let submit_event = SubmittedEvent { event: e.clone(), notice_tx: notice_tx.clone() };
event_tx.send(submit_event).await.ok();
client_published_event_count += 1;
} else {
info!("client: {} sent a far future-dated event", cid);
if let Some(fut_sec) = settings.options.reject_future_seconds {
let msg = format!("The event created_at field is out of the acceptable range (+{}sec) for this relay.",fut_sec);
let notice = Notice::invalid(e.id, &msg);
ws_stream.send(make_notice_message(notice)).await.ok();
}
}
},
Err(e) => {
info!("client sent an invalid event (cid: {})", cid);
ws_stream.send(make_notice_message(Notice::invalid(evid, &format!("{}", e)))).await.ok();
}
}
},
Ok(NostrMessage::SubMsg(s)) => {
debug!("subscription requested (cid: {}, sub: {:?})", cid, s.id);
// subscription handling consists of:
// * check for rate limits
// * registering the subscription so future events can be matched
// * making a channel to cancel to request later
// * sending a request for a SQL query
// Do nothing if the sub already exists.
if !conn.has_subscription(&s) {
if let Some(ref lim) = sub_lim_opt {
lim.until_ready_with_jitter(jitter).await;
}
let (abandon_query_tx, abandon_query_rx) = oneshot::channel::<()>();
match conn.subscribe(s.clone()) {
Ok(()) => {
// when we insert, if there was a previous query running with the same name, cancel it.
if let Some(previous_query) = running_queries.insert(s.id.to_owned(), abandon_query_tx) {
previous_query.send(()).ok();
}
// start a database query. this spawns a blocking database query on a worker thread.
db::db_query(s, cid.to_owned(), pool.clone(), query_tx.clone(), abandon_query_rx).await;
},
Err(e) => {
info!("Subscription error: {} (cid: {}, sub: {:?})", e, cid, s.id);
ws_stream.send(make_notice_message(Notice::message(format!("Subscription error: {}", e)))).await.ok();
}
}
} else {
info!("client sent duplicate subscription, ignoring (cid: {}, sub: {:?})", cid, s.id);
}
},
Ok(NostrMessage::CloseMsg(cc)) => {
// closing a request simply removes the subscription.
let parsed : Result<Close> = Result::<Close>::from(cc);
if let Ok(c) = parsed {
// check if a query is currently
// running, and remove it if so.
let stop_tx = running_queries.remove(&c.id);
if let Some(tx) = stop_tx {
tx.send(()).ok();
}
// stop checking new events against
// the subscription
conn.unsubscribe(&c);
} else {
info!("invalid command ignored");
ws_stream.send(make_notice_message(Notice::message("could not parse command".into()))).await.ok();
}
},
Err(Error::ConnError) => {
debug!("got connection close/error, disconnecting cid: {}, ip: {:?}",cid, conn.ip());
break;
}
Err(Error::EventMaxLengthError(s)) => {
info!("client sent event larger ({} bytes) than max size (cid: {})", s, cid);
ws_stream.send(make_notice_message(Notice::message("event exceeded max size".into()))).await.ok();
},
Err(Error::ProtoParseError) => {
info!("client sent event that could not be parsed (cid: {})", cid);
ws_stream.send(make_notice_message(Notice::message("could not parse command".into()))).await.ok();
},
Err(e) => {
info!("got non-fatal error from client (cid: {}, error: {:?}", cid, e);
},
}
},
}
}
// connection cleanup - ensure any still running queries are terminated.
for (_, stop_tx) in running_queries {
stop_tx.send(()).ok();
}
info!(
"stopping client connection (cid: {}, ip: {:?}, sent: {} events, recv: {} events, connected: {:?})",
cid,
conn.ip(),
client_published_event_count,
client_received_event_count,
orig_start.elapsed()
);
}