Files
RuDS/crates/bds-server/src/transport.rs

524 lines
18 KiB
Rust

use std::collections::HashMap;
use std::net::{IpAddr, Ipv4Addr, SocketAddr};
use std::path::PathBuf;
use std::sync::Arc;
use std::thread::JoinHandle;
use std::time::Duration;
use anyhow::{Context, Result, anyhow};
use bds_core::engine::mcp::McpHttpServer;
use russh::keys::PublicKey;
use russh::server::{Auth, ChannelOpenHandle, Handler, Msg, Server, Session};
use russh::{Channel, ChannelId};
use tokio::io::{AsyncBufReadExt as _, AsyncWrite, AsyncWriteExt as _, BufReader};
use crate::auth::KeyMaterial;
use crate::host::{ApplicationHost, ApplicationSession};
use crate::protocol::{Command, PROTOCOL_VERSION, Request, SUBSYSTEM, ServerMessage};
#[derive(Debug, Clone)]
pub struct ServerConfig {
pub database_path: PathBuf,
pub data_root: PathBuf,
pub bind: IpAddr,
pub port: u16,
pub mcp_port: u16,
}
impl ServerConfig {
pub fn local(database_path: PathBuf, data_root: PathBuf) -> Self {
Self {
database_path,
data_root,
bind: IpAddr::V4(Ipv4Addr::LOCALHOST),
port: 2222,
mcp_port: 0,
}
}
pub fn from_environment(database_path: PathBuf, data_root: PathBuf) -> Result<Self> {
let mut config = Self::local(database_path, data_root);
if let Some(bind) = std::env::var_os("BDS_SSH_BIND") {
config.bind = bind
.to_string_lossy()
.parse()
.context("BDS_SSH_BIND must be an IP address")?;
}
if let Some(port) = std::env::var_os("BDS_SSH_PORT") {
config.port = port
.to_string_lossy()
.parse()
.context("BDS_SSH_PORT must be a TCP port")?;
}
Ok(config)
}
}
pub struct ServerRuntime {
address: SocketAddr,
key_material: KeyMaterial,
host: ApplicationHost,
shutdown: Option<tokio::sync::oneshot::Sender<()>>,
thread: Option<JoinHandle<Result<()>>>,
_mcp: McpHttpServer,
}
impl ServerRuntime {
pub fn start(config: ServerConfig) -> Result<Self> {
let key_material = KeyMaterial::ensure(&config.data_root)?;
let host = ApplicationHost::start(config.database_path.clone(), config.data_root.clone())?;
let server_host = host.clone();
let mcp = McpHttpServer::start(config.database_path, config.mcp_port)?;
let forward_address = mcp.address();
let listener =
std::net::TcpListener::bind((config.bind, config.port)).with_context(|| {
format!(
"could not bind the RuDS SSH server to {}:{}",
config.bind, config.port
)
})?;
listener.set_nonblocking(true)?;
let address = listener.local_addr()?;
let host_key = key_material.host_key()?;
let auth = key_material.clone();
let (shutdown, shutdown_rx) = tokio::sync::oneshot::channel();
let thread = std::thread::Builder::new()
.name("bds-ssh-server".into())
.spawn(move || -> Result<()> {
let runtime = tokio::runtime::Builder::new_multi_thread()
.worker_threads(2)
.enable_all()
.build()?;
runtime.block_on(async move {
let listener = tokio::net::TcpListener::from_std(listener)?;
let ssh_config = Arc::new(russh::server::Config {
inactivity_timeout: Some(Duration::from_secs(60 * 60)),
auth_rejection_time: Duration::from_millis(500),
auth_rejection_time_initial: Some(Duration::ZERO),
keys: vec![host_key],
nodelay: true,
..Default::default()
});
let mut factory = ServerFactory {
auth,
host: server_host,
forward_address,
};
let running = factory.run_on_socket(ssh_config, &listener);
let handle = running.handle();
tokio::spawn(async move {
let _ = shutdown_rx.await;
handle.shutdown("RuDS server is shutting down".into());
});
running.await.map_err(anyhow::Error::from)
})
})?;
Ok(Self {
address,
key_material,
host,
shutdown: Some(shutdown),
thread: Some(thread),
_mcp: mcp,
})
}
pub fn address(&self) -> SocketAddr {
self.address
}
pub fn key_material(&self) -> &KeyMaterial {
&self.key_material
}
pub fn application_host(&self) -> ApplicationHost {
self.host.clone()
}
pub fn stop(mut self) -> Result<()> {
self.shutdown.take();
if let Some(thread) = self.thread.take() {
thread
.join()
.map_err(|_| anyhow!("RuDS SSH server thread panicked"))??;
}
Ok(())
}
}
impl Drop for ServerRuntime {
fn drop(&mut self) {
self.shutdown.take();
if let Some(thread) = self.thread.take() {
let _ = thread.join();
}
}
}
struct ServerFactory {
auth: KeyMaterial,
host: ApplicationHost,
forward_address: SocketAddr,
}
impl Server for ServerFactory {
type Handler = ConnectionHandler;
fn new_client(&mut self, _peer_addr: Option<SocketAddr>) -> Self::Handler {
ConnectionHandler {
auth: self.auth.clone(),
host: self.host.clone(),
forward_address: self.forward_address,
channels: HashMap::new(),
}
}
}
struct ConnectionHandler {
auth: KeyMaterial,
host: ApplicationHost,
forward_address: SocketAddr,
channels: HashMap<ChannelId, Channel<Msg>>,
}
impl Handler for ConnectionHandler {
type Error = anyhow::Error;
async fn auth_publickey(&mut self, _user: &str, key: &PublicKey) -> Result<Auth, Self::Error> {
Ok(if self.auth.authorizes(key)? {
Auth::Accept
} else {
Auth::reject()
})
}
async fn channel_open_session(
&mut self,
channel: Channel<Msg>,
reply: ChannelOpenHandle,
_session: &mut Session,
) -> Result<(), Self::Error> {
self.channels.insert(channel.id(), channel);
reply.accept().await;
Ok(())
}
async fn pty_request(
&mut self,
channel: ChannelId,
_term: &str,
_col_width: u32,
_row_height: u32,
_pix_width: u32,
_pix_height: u32,
_modes: &[(russh::Pty, u32)],
session: &mut Session,
) -> Result<(), Self::Error> {
session.channel_success(channel)?;
Ok(())
}
async fn subsystem_request(
&mut self,
channel: ChannelId,
name: &str,
session: &mut Session,
) -> Result<(), Self::Error> {
if name != SUBSYSTEM {
session.channel_failure(channel)?;
return Ok(());
}
let Some(channel) = self.channels.remove(&channel) else {
session.channel_failure(channel)?;
return Ok(());
};
let application = self.host.session()?;
session.channel_success(channel.id())?;
tokio::spawn(async move {
let _ = run_protocol(channel, application).await;
});
Ok(())
}
async fn shell_request(
&mut self,
channel: ChannelId,
session: &mut Session,
) -> Result<(), Self::Error> {
let Some(channel) = self.channels.remove(&channel) else {
session.channel_failure(channel)?;
return Ok(());
};
let application = self.host.session()?;
session.channel_success(channel.id())?;
tokio::spawn(async move {
let _ = run_terminal_session(channel, application).await;
});
Ok(())
}
async fn channel_open_direct_tcpip(
&mut self,
channel: Channel<Msg>,
host_to_connect: &str,
port_to_connect: u32,
_originator_address: &str,
_originator_port: u32,
reply: ChannelOpenHandle,
_session: &mut Session,
) -> Result<(), Self::Error> {
let permitted_host = matches!(host_to_connect, "127.0.0.1" | "localhost" | "::1");
if !permitted_host || port_to_connect != u32::from(self.forward_address.port()) {
return Ok(());
}
let Ok(mut target) = tokio::net::TcpStream::connect(self.forward_address).await else {
return Ok(());
};
reply.accept().await;
tokio::spawn(async move {
let mut stream = channel.into_stream();
let _ = tokio::io::copy_bidirectional(&mut stream, &mut target).await;
});
Ok(())
}
}
async fn run_protocol(channel: Channel<Msg>, mut application: ApplicationSession) -> Result<()> {
let (read, mut write) = tokio::io::split(channel.into_stream());
let mut lines = BufReader::new(read).lines();
let mut interval = tokio::time::interval(Duration::from_millis(100));
loop {
tokio::select! {
line = lines.next_line() => {
let Some(line) = line? else { break };
let response = if line.len() > 1024 * 1024 {
ServerMessage::Error { id: String::new(), code: "request_too_large".into(), message: "remote request exceeds 1 MiB".into() }
} else {
match serde_json::from_str::<Request>(&line) {
Ok(request) => application.handle(request),
Err(error) => ServerMessage::Error { id: String::new(), code: "invalid_request".into(), message: error.to_string() },
}
};
write_message(&mut write, &response).await?;
}
_ = interval.tick() => {
for message in application.pending() {
write_message(&mut write, &message).await?;
}
}
}
}
Ok(())
}
async fn write_message(
write: &mut (impl AsyncWrite + Unpin),
message: &ServerMessage,
) -> Result<()> {
let mut encoded = serde_json::to_vec(message)?;
encoded.push(b'\n');
write.write_all(&encoded).await?;
write.flush().await?;
Ok(())
}
async fn run_terminal_session(
mut channel: Channel<Msg>,
mut application: ApplicationSession,
) -> Result<()> {
let locale = application.locale().to_owned();
let hello = application.handle(Request {
id: "terminal-hello".into(),
command: Command::Hello {
protocol_version: PROTOCOL_VERSION,
},
});
if matches!(hello, ServerMessage::Error { .. }) {
return Err(anyhow!("terminal protocol negotiation failed"));
}
let projects = application.handle(Request {
id: "terminal-projects".into(),
command: Command::ListProjects,
});
let project_names = match projects {
ServerMessage::Response { result, .. } => result
.as_array()
.into_iter()
.flatten()
.filter_map(|project| project.get("name").and_then(|name| name.as_str()))
.collect::<Vec<_>>()
.join("\r\n"),
_ => String::new(),
};
let banner = terminal_banner(&locale, &project_names);
channel.data(banner.as_bytes()).await?;
let mut interval = tokio::time::interval(Duration::from_millis(250));
loop {
tokio::select! {
message = channel.wait() => match message {
Some(russh::ChannelMsg::Data { data }) if data.iter().any(|byte| matches!(byte, b'q' | 3)) => {
channel.close().await?;
break;
}
None | Some(russh::ChannelMsg::Close) => break,
_ => {}
},
_ = interval.tick() => {
let updates = application.pending();
if !updates.is_empty() {
let status = format!("\r\n[{} update{}]\r\n", updates.len(), if updates.len() == 1 { "" } else { "s" });
channel.data(status.as_bytes()).await?;
}
}
}
}
Ok(())
}
fn terminal_banner(locale: &str, projects: &str) -> String {
let locale = bds_core::i18n::normalize_language(locale);
let title = bds_core::i18n::translate(locale, "remoteTerminal.serverTitle");
let available = bds_core::i18n::translate(locale, "remoteTerminal.availableProjects");
let quit = bds_core::i18n::translate(locale, "remoteTerminal.quit");
let projects = if projects.is_empty() { "" } else { projects };
format!("\x1b[2J\x1b[H{title}\r\n\r\n{available}:\r\n{projects}\r\n\r\n{quit}\r\n")
}
#[cfg(test)]
mod tests {
use super::*;
use crate::auth::ClientKeyMaterial;
use crate::client::{DesktopClient, RemoteTarget};
use bds_core::db::Database;
use std::fs;
use std::thread;
#[test]
fn defaults_to_loopback_and_external_binding_requires_an_explicit_value() {
let config = ServerConfig::local("db".into(), "data".into());
assert_eq!(config.bind, IpAddr::V4(Ipv4Addr::LOCALHOST));
assert_eq!(config.port, 2222);
}
#[test]
fn terminal_banner_uses_the_server_locale_and_only_terminal_control_bytes() {
let banner = terminal_banner("de", "Blog");
assert!(banner.starts_with("\x1b[2J\x1b[H"));
assert!(banner.contains("RuDS-Serversitzung"));
assert!(banner.contains("Blog"));
assert!(!banner.contains('{'));
}
#[test]
fn real_ssh_authentication_revocation_reconnect_events_and_shutdown() {
let root = tempfile::tempdir().unwrap();
let server_data = root.path().join("server");
let client_data = root.path().join("client");
let unknown_data = root.path().join("unknown");
fs::create_dir_all(&server_data).unwrap();
let database_path = server_data.join("bds.db");
let db = Database::open(&database_path).unwrap();
db.migrate().unwrap();
let project_dir = root.path().join("blog");
let project = bds_core::engine::project::create_project(
db.conn(),
"Remote Blog",
Some(project_dir.to_str().unwrap()),
)
.unwrap();
bds_core::engine::settings::set(
db.conn(),
bds_core::engine::settings::UI_LANGUAGE_KEY,
"fr",
)
.unwrap();
let runtime = ServerRuntime::start(ServerConfig {
database_path,
data_root: server_data.clone(),
bind: IpAddr::V4(Ipv4Addr::LOCALHOST),
port: 0,
mcp_port: 0,
})
.unwrap();
let target = RemoteTarget {
user: "author".into(),
host: runtime.address().ip().to_string(),
port: runtime.address().port(),
};
let unknown = match DesktopClient::connect(target.clone(), &unknown_data) {
Ok(_) => panic!("unknown key authenticated"),
Err(error) => error,
};
assert!(
unknown
.to_string()
.contains("public-key authentication failed")
);
let identity = ClientKeyMaterial::ensure(&client_data).unwrap();
let public_key = fs::read_to_string(&identity.public_key_path).unwrap();
fs::write(&runtime.key_material().authorized_keys_path, &public_key).unwrap();
let first = DesktopClient::connect(target.clone(), &client_data).unwrap();
let second = DesktopClient::connect(target.clone(), &client_data).unwrap();
assert_eq!(first.server_locale(), "fr");
assert_eq!(second.server_locale(), "fr");
assert_eq!(first.list_projects().unwrap()[0].name, "Remote Blog");
first.open_project(&project.id).unwrap();
second.open_project(&project.id).unwrap();
let _ = first.drain_events();
let _ = second.drain_events();
first
.call(
"posts",
"create",
vec![serde_json::json!({"title":"Over SSH","content":"body"})],
)
.unwrap();
thread::sleep(Duration::from_millis(250));
assert_eq!(domain_event_count(&first.drain_events(), &project.id), 1);
assert_eq!(domain_event_count(&second.drain_events(), &project.id), 1);
assert_eq!(
bds_core::db::queries::post::list_posts_by_project(db.conn(), &project.id)
.unwrap()
.len(),
1
);
// Revocation affects new authentication attempts immediately without
// corrupting an already authenticated session.
fs::write(&runtime.key_material().authorized_keys_path, "").unwrap();
first.ping().unwrap();
second.disconnect().unwrap();
let revoked = match DesktopClient::connect(target.clone(), &client_data) {
Ok(_) => panic!("revoked key authenticated"),
Err(error) => error,
};
assert!(
revoked
.to_string()
.contains("public-key authentication failed")
);
fs::write(&runtime.key_material().authorized_keys_path, public_key).unwrap();
let reconnected = DesktopClient::connect(target, &client_data).unwrap();
reconnected.ping().unwrap();
reconnected.disconnect().unwrap();
runtime.stop().unwrap();
assert!(first.ping().is_err());
first.disconnect().unwrap();
}
fn domain_event_count(messages: &[ServerMessage], project_id: &str) -> usize {
messages
.iter()
.filter(|message| {
matches!(message, ServerMessage::Event { event, .. } if event.project_id() == Some(project_id))
})
.count()
}
}