Line data Source code
1 : /// A stand-alone program that routes connections, e.g. from
2 : /// `aaa--bbb--1234.external.domain` to `aaa.bbb.internal.domain:1234`.
3 : ///
4 : /// This allows connecting to pods/services running in the same Kubernetes cluster from
5 : /// the outside. Similar to an ingress controller for HTTPS.
6 : use std::{net::SocketAddr, sync::Arc};
7 :
8 : use crate::context::RequestContext;
9 : use crate::metrics::{Metrics, ThreadPoolMetrics};
10 : use crate::protocol2::ConnectionInfo;
11 : use crate::proxy::{copy_bidirectional_client_compute, run_until_cancelled, ErrorSource};
12 : use crate::stream::{PqStream, Stream};
13 : use crate::tls::TlsServerEndPoint;
14 : use anyhow::{anyhow, bail, ensure, Context};
15 : use clap::Arg;
16 : use futures::future::Either;
17 : use futures::TryFutureExt;
18 : use itertools::Itertools;
19 : use rustls::crypto::ring;
20 : use rustls::pki_types::PrivateKeyDer;
21 : use tokio::io::{AsyncRead, AsyncWrite};
22 : use tokio::net::TcpListener;
23 : use tokio_util::sync::CancellationToken;
24 : use tracing::{error, info, Instrument};
25 : use utils::project_git_version;
26 : use utils::sentry_init::init_sentry;
27 :
28 : project_git_version!(GIT_VERSION);
29 :
30 0 : fn cli() -> clap::Command {
31 0 : clap::Command::new("Neon proxy/router")
32 0 : .version(GIT_VERSION)
33 0 : .arg(
34 0 : Arg::new("listen")
35 0 : .short('l')
36 0 : .long("listen")
37 0 : .help("listen for incoming client connections on ip:port")
38 0 : .default_value("127.0.0.1:4432"),
39 0 : )
40 0 : .arg(
41 0 : Arg::new("tls-key")
42 0 : .short('k')
43 0 : .long("tls-key")
44 0 : .help("path to TLS key for client postgres connections")
45 0 : .required(true),
46 0 : )
47 0 : .arg(
48 0 : Arg::new("tls-cert")
49 0 : .short('c')
50 0 : .long("tls-cert")
51 0 : .help("path to TLS cert for client postgres connections")
52 0 : .required(true),
53 0 : )
54 0 : .arg(
55 0 : Arg::new("dest")
56 0 : .short('d')
57 0 : .long("destination")
58 0 : .help("append this domain zone to the SNI hostname to get the destination address")
59 0 : .required(true),
60 0 : )
61 0 : }
62 :
63 0 : pub async fn run() -> anyhow::Result<()> {
64 0 : let _logging_guard = crate::logging::init().await?;
65 0 : let _panic_hook_guard = utils::logging::replace_panic_hook_with_tracing_panic_hook();
66 0 : let _sentry_guard = init_sentry(Some(GIT_VERSION.into()), &[]);
67 0 :
68 0 : Metrics::install(Arc::new(ThreadPoolMetrics::new(0)));
69 0 :
70 0 : let args = cli().get_matches();
71 0 : let destination: String = args
72 0 : .get_one::<String>("dest")
73 0 : .expect("string argument defined")
74 0 : .parse()?;
75 :
76 : // Configure TLS
77 0 : let (tls_config, tls_server_end_point): (Arc<rustls::ServerConfig>, TlsServerEndPoint) = match (
78 0 : args.get_one::<String>("tls-key"),
79 0 : args.get_one::<String>("tls-cert"),
80 : ) {
81 0 : (Some(key_path), Some(cert_path)) => {
82 0 : let key = {
83 0 : let key_bytes = std::fs::read(key_path).context("TLS key file")?;
84 :
85 0 : let mut keys =
86 0 : rustls_pemfile::pkcs8_private_keys(&mut &key_bytes[..]).collect_vec();
87 0 :
88 0 : ensure!(keys.len() == 1, "keys.len() = {} (should be 1)", keys.len());
89 : PrivateKeyDer::Pkcs8(
90 0 : keys.pop()
91 0 : .expect("keys should not be empty")
92 0 : .context(format!("Failed to read TLS keys at '{key_path}'"))?,
93 : )
94 : };
95 :
96 0 : let cert_chain_bytes = std::fs::read(cert_path)
97 0 : .context(format!("Failed to read TLS cert file at '{cert_path}.'"))?;
98 :
99 0 : let cert_chain: Vec<_> = {
100 0 : rustls_pemfile::certs(&mut &cert_chain_bytes[..])
101 0 : .try_collect()
102 0 : .with_context(|| {
103 0 : format!("Failed to read TLS certificate chain from bytes from file at '{cert_path}'.")
104 0 : })?
105 : };
106 :
107 : // needed for channel bindings
108 0 : let first_cert = cert_chain.first().context("missing certificate")?;
109 0 : let tls_server_end_point = TlsServerEndPoint::new(first_cert)?;
110 :
111 0 : let tls_config =
112 0 : rustls::ServerConfig::builder_with_provider(Arc::new(ring::default_provider()))
113 0 : .with_protocol_versions(&[&rustls::version::TLS13, &rustls::version::TLS12])
114 0 : .context("ring should support TLS1.2 and TLS1.3")?
115 0 : .with_no_client_auth()
116 0 : .with_single_cert(cert_chain, key)?
117 0 : .into();
118 0 :
119 0 : (tls_config, tls_server_end_point)
120 : }
121 0 : _ => bail!("tls-key and tls-cert must be specified"),
122 : };
123 :
124 : // Start listening for incoming client connections
125 0 : let proxy_address: SocketAddr = args
126 0 : .get_one::<String>("listen")
127 0 : .expect("string argument defined")
128 0 : .parse()?;
129 0 : info!("Starting sni router on {proxy_address}");
130 0 : let proxy_listener = TcpListener::bind(proxy_address).await?;
131 :
132 0 : let cancellation_token = CancellationToken::new();
133 0 :
134 0 : let main = tokio::spawn(task_main(
135 0 : Arc::new(destination),
136 0 : tls_config,
137 0 : tls_server_end_point,
138 0 : proxy_listener,
139 0 : cancellation_token.clone(),
140 0 : ));
141 0 : let signals_task = tokio::spawn(crate::signals::handle(cancellation_token, || {}));
142 0 :
143 0 : // the signal task cant ever succeed.
144 0 : // the main task can error, or can succeed on cancellation.
145 0 : // we want to immediately exit on either of these cases
146 0 : let signal = match futures::future::select(signals_task, main).await {
147 0 : Either::Left((res, _)) => crate::error::flatten_err(res)?,
148 0 : Either::Right((res, _)) => return crate::error::flatten_err(res),
149 : };
150 :
151 : // maintenance tasks return `Infallible` success values, this is an impossible value
152 : // so this match statically ensures that there are no possibilities for that value
153 : match signal {}
154 0 : }
155 :
156 0 : async fn task_main(
157 0 : dest_suffix: Arc<String>,
158 0 : tls_config: Arc<rustls::ServerConfig>,
159 0 : tls_server_end_point: TlsServerEndPoint,
160 0 : listener: tokio::net::TcpListener,
161 0 : cancellation_token: CancellationToken,
162 0 : ) -> anyhow::Result<()> {
163 0 : // When set for the server socket, the keepalive setting
164 0 : // will be inherited by all accepted client sockets.
165 0 : socket2::SockRef::from(&listener).set_keepalive(true)?;
166 :
167 0 : let connections = tokio_util::task::task_tracker::TaskTracker::new();
168 :
169 0 : while let Some(accept_result) =
170 0 : run_until_cancelled(listener.accept(), &cancellation_token).await
171 : {
172 0 : let (socket, peer_addr) = accept_result?;
173 :
174 0 : let session_id = uuid::Uuid::new_v4();
175 0 : let tls_config = Arc::clone(&tls_config);
176 0 : let dest_suffix = Arc::clone(&dest_suffix);
177 0 :
178 0 : connections.spawn(
179 0 : async move {
180 0 : socket
181 0 : .set_nodelay(true)
182 0 : .context("failed to set socket option")?;
183 :
184 0 : info!(%peer_addr, "serving");
185 0 : let ctx = RequestContext::new(
186 0 : session_id,
187 0 : ConnectionInfo {
188 0 : addr: peer_addr,
189 0 : extra: None,
190 0 : },
191 0 : crate::metrics::Protocol::SniRouter,
192 0 : "sni",
193 0 : );
194 0 : handle_client(ctx, dest_suffix, tls_config, tls_server_end_point, socket).await
195 0 : }
196 0 : .unwrap_or_else(|e| {
197 0 : // Acknowledge that the task has finished with an error.
198 0 : error!("per-client task finished with an error: {e:#}");
199 0 : })
200 0 : .instrument(tracing::info_span!("handle_client", ?session_id)),
201 : );
202 : }
203 :
204 0 : connections.close();
205 0 : drop(listener);
206 0 :
207 0 : connections.wait().await;
208 :
209 0 : info!("all client connections have finished");
210 0 : Ok(())
211 0 : }
212 :
213 : const ERR_INSECURE_CONNECTION: &str = "connection is insecure (try using `sslmode=require`)";
214 :
215 0 : async fn ssl_handshake<S: AsyncRead + AsyncWrite + Unpin>(
216 0 : ctx: &RequestContext,
217 0 : raw_stream: S,
218 0 : tls_config: Arc<rustls::ServerConfig>,
219 0 : tls_server_end_point: TlsServerEndPoint,
220 0 : ) -> anyhow::Result<Stream<S>> {
221 0 : let mut stream = PqStream::new(Stream::from_raw(raw_stream));
222 :
223 0 : let msg = stream.read_startup_packet().await?;
224 : use pq_proto::FeStartupPacket::SslRequest;
225 :
226 0 : match msg {
227 : SslRequest { direct: false } => {
228 0 : stream
229 0 : .write_message(&pq_proto::BeMessage::EncryptionResponse(true))
230 0 : .await?;
231 :
232 : // Upgrade raw stream into a secure TLS-backed stream.
233 : // NOTE: We've consumed `tls`; this fact will be used later.
234 :
235 0 : let (raw, read_buf) = stream.into_inner();
236 0 : // TODO: Normally, client doesn't send any data before
237 0 : // server says TLS handshake is ok and read_buf is empty.
238 0 : // However, you could imagine pipelining of postgres
239 0 : // SSLRequest + TLS ClientHello in one hunk similar to
240 0 : // pipelining in our node js driver. We should probably
241 0 : // support that by chaining read_buf with the stream.
242 0 : if !read_buf.is_empty() {
243 0 : bail!("data is sent before server replied with EncryptionResponse");
244 0 : }
245 0 :
246 0 : Ok(Stream::Tls {
247 0 : tls: Box::new(
248 0 : raw.upgrade(tls_config, !ctx.has_private_peer_addr())
249 0 : .await?,
250 : ),
251 0 : tls_server_end_point,
252 : })
253 : }
254 0 : unexpected => {
255 0 : info!(
256 : ?unexpected,
257 0 : "unexpected startup packet, rejecting connection"
258 : );
259 0 : stream
260 0 : .throw_error_str(ERR_INSECURE_CONNECTION, crate::error::ErrorKind::User)
261 0 : .await?
262 : }
263 : }
264 0 : }
265 :
266 0 : async fn handle_client(
267 0 : ctx: RequestContext,
268 0 : dest_suffix: Arc<String>,
269 0 : tls_config: Arc<rustls::ServerConfig>,
270 0 : tls_server_end_point: TlsServerEndPoint,
271 0 : stream: impl AsyncRead + AsyncWrite + Unpin,
272 0 : ) -> anyhow::Result<()> {
273 0 : let mut tls_stream = ssl_handshake(&ctx, stream, tls_config, tls_server_end_point).await?;
274 :
275 : // Cut off first part of the SNI domain
276 : // We receive required destination details in the format of
277 : // `{k8s_service_name}--{k8s_namespace}--{port}.non-sni-domain`
278 0 : let sni = tls_stream.sni_hostname().ok_or(anyhow!("SNI missing"))?;
279 0 : let dest: Vec<&str> = sni
280 0 : .split_once('.')
281 0 : .context("invalid SNI")?
282 : .0
283 0 : .splitn(3, "--")
284 0 : .collect();
285 0 : let port = dest[2].parse::<u16>().context("invalid port")?;
286 0 : let destination = format!("{}.{}.{}:{}", dest[0], dest[1], dest_suffix, port);
287 0 :
288 0 : info!("destination: {}", destination);
289 :
290 0 : let mut client = tokio::net::TcpStream::connect(destination).await?;
291 :
292 : // doesn't yet matter as pg-sni-router doesn't report analytics logs
293 0 : ctx.set_success();
294 0 : ctx.log_connect();
295 0 :
296 0 : // Starting from here we only proxy the client's traffic.
297 0 : info!("performing the proxy pass...");
298 :
299 0 : match copy_bidirectional_client_compute(&mut tls_stream, &mut client).await {
300 0 : Ok(_) => Ok(()),
301 0 : Err(ErrorSource::Client(err)) => Err(err).context("client"),
302 0 : Err(ErrorSource::Compute(err)) => Err(err).context("compute"),
303 : }
304 0 : }
|
