Merge remote-tracking branch 'origin/feat/ssh-session-call-protocol-bridge'

This commit is contained in:
2026-06-09 10:56:57 +00:00
5 changed files with 333 additions and 19 deletions

View File

@@ -1,3 +1,7 @@
use std::io;
use tokio::io::{AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt};
use crate::call::envelope::EventEnvelope;
pub fn encode(envelope: &EventEnvelope) -> Vec<u8> {
@@ -58,6 +62,73 @@ pub enum FrameDecodeError {
Json(#[from] serde_json::Error),
}
pub struct FrameFramedReader<S> {
stream: S,
buf: Vec<u8>,
}
impl<S> FrameFramedReader<S>
where
S: AsyncRead + Unpin,
{
pub fn new(stream: S) -> Self {
Self {
stream,
buf: Vec::with_capacity(4096),
}
}
pub async fn read_frame(&mut self) -> io::Result<Option<EventEnvelope>> {
loop {
if self.buf.len() >= 4 {
let len = u32::from_be_bytes([self.buf[0], self.buf[1], self.buf[2], self.buf[3]])
as usize;
let total = 4 + len;
if self.buf.len() >= total {
let body = &self.buf[4..total];
match serde_json::from_slice(body) {
Ok(envelope) => {
self.buf.drain(..total);
return Ok(Some(envelope));
}
Err(e) => {
self.buf.drain(..total);
return Err(io::Error::new(io::ErrorKind::InvalidData, e));
}
}
}
}
let mut tmp = [0u8; 4096];
match self.stream.read(&mut tmp).await {
Ok(0) => return Ok(None),
Ok(n) => self.buf.extend_from_slice(&tmp[..n]),
Err(e) => return Err(e),
}
}
}
}
pub struct FrameFramedWriter<S> {
stream: S,
}
impl<S> FrameFramedWriter<S>
where
S: AsyncWrite + Unpin,
{
pub fn new(stream: S) -> Self {
Self { stream }
}
pub async fn write_frame(&mut self, envelope: &EventEnvelope) -> io::Result<()> {
let frame = encode(envelope);
self.stream.write_all(&frame).await?;
self.stream.flush().await?;
Ok(())
}
}
#[cfg(test)]
mod tests {
use super::*;

View File

@@ -18,7 +18,9 @@ pub use context::OperationContext;
pub use env::OperationEnv;
pub use envelope::EventEnvelope;
pub use events::{CALL_ABORTED, CALL_COMPLETED, CALL_ERROR, CALL_REQUESTED, CALL_RESPONDED};
pub use frame::{decode, decode_with_remainder, encode, FrameDecodeError};
pub use frame::{
decode, decode_with_remainder, encode, FrameDecodeError, FrameFramedReader, FrameFramedWriter,
};
pub use pending::PendingRequestMap;
pub use registry::{Handler, OperationRegistry, OperationRegistryBuilder};
pub use response::{CallError, ResponseEnvelope};

View File

@@ -35,7 +35,7 @@ pub use http::HttpInterface;
pub use pairs::{is_valid_pair, TransportKindBase, VALID_TRANSPORT_INTERFACE_PAIRS};
pub use raw_framing::{RawFramingInterface, RawFramingSession};
pub use session::{InterfaceEvent, InterfaceSession};
pub use ssh::{SshInterface, SshSession};
pub use ssh::{ControlChannelBridge, SshInterface, SshSession};
pub trait TransportStream: AsyncRead + AsyncWrite + Unpin + Send + 'static {}

View File

@@ -9,13 +9,18 @@ use russh::keys::ssh_key::HashAlg;
use russh::server::{self, Config};
use russh::Channel;
use russh::ChannelId;
use tokio::sync::mpsc;
use crate::auth::identity::{Identity, IdentityProvider};
use crate::call::frame::{FrameFramedReader, FrameFramedWriter};
use crate::call::EventEnvelope;
use crate::config::DynamicConfig;
use crate::interface::session::{InterfaceEvent, InterfaceSession};
use crate::interface::{StreamInterface, StreamInterfaceConfig, TransportStream};
use crate::server::control_channel::{ControlChannelRouter, ALKNET_PREFIX};
use crate::server::control_channel::{
ControlChannelHandler, ControlChannelRouter, DuplexStream, ALKNET_CONTROL_DESTINATION,
ALKNET_PREFIX,
};
use crate::server::rate_limit::{AuthAttemptLimiter, ConnectionRateLimiter};
use crate::transport::TransportKind;
@@ -30,6 +35,8 @@ struct SshHandler {
auth_limiter: AuthAttemptLimiter,
authenticated_identity: Option<Identity>,
control_channel_router: ControlChannelRouter,
bridge_event_tx: Option<mpsc::Sender<InterfaceEvent>>,
bridge_envelope_rx: Option<mpsc::Receiver<EventEnvelope>>,
connected_at: Instant,
}
@@ -76,6 +83,8 @@ impl SshHandler {
auth_limiter: AuthAttemptLimiter::new(max_auth_attempts),
authenticated_identity: None,
control_channel_router: ControlChannelRouter::without_handler(),
bridge_event_tx: None,
bridge_envelope_rx: None,
connected_at: Instant::now(),
}
}
@@ -85,6 +94,20 @@ impl SshHandler {
self.control_channel_router = router;
self
}
fn with_bridge_channels(
mut self,
event_tx: mpsc::Sender<InterfaceEvent>,
envelope_rx: mpsc::Receiver<EventEnvelope>,
) -> Self {
self.bridge_event_tx = Some(event_tx);
self.bridge_envelope_rx = Some(envelope_rx);
self
}
fn has_control_channel_bridge(&self) -> bool {
self.bridge_event_tx.is_some() && self.bridge_envelope_rx.is_some()
}
}
impl Drop for SshHandler {
@@ -176,12 +199,37 @@ impl server::Handler for SshHandler {
_session: &mut server::Session,
) -> Result<bool, Self::Error> {
if host_to_connect.starts_with(ALKNET_PREFIX) {
if !self.control_channel_router.has_handler() {
return Ok(false);
}
let _ = channel;
if host_to_connect == ALKNET_CONTROL_DESTINATION && self.has_control_channel_bridge() {
let event_tx = self.bridge_event_tx.take().unwrap();
let envelope_rx = self.bridge_envelope_rx.take().unwrap();
let identity = self.authenticated_identity.clone();
tokio::spawn(async move {
let stream = channel.into_stream();
let (read_half, write_half) = tokio::io::split(stream);
run_control_channel_bridge(
read_half,
write_half,
identity,
event_tx,
envelope_rx,
)
.await;
});
let _ = (originator_address, originator_port);
return Ok(true);
}
if self.control_channel_router.has_handler() {
if let Some(handler) = self.control_channel_router.take_handler() {
let stream: Box<dyn DuplexStream> = Box::new(channel.into_stream());
tokio::spawn(async move {
handler.handle_channel(stream).await;
});
}
let _ = (originator_address, originator_port);
return Ok(true);
}
return Ok(false);
}
let identity = self
.authenticated_identity
@@ -529,6 +577,9 @@ impl SshInterface {
let identity_provider = Arc::clone(&ssh_config.auth);
let _forwarding = Arc::clone(&ssh_config.forwarding);
let (event_tx, event_rx) = mpsc::channel::<InterfaceEvent>(256);
let (envelope_tx, envelope_rx) = mpsc::channel::<EventEnvelope>(256);
let handler = SshHandler::new(
Arc::clone(&self.dynamic),
identity_provider,
@@ -537,7 +588,8 @@ impl SshInterface {
transport,
Arc::clone(&self.connection_limiter),
self.max_auth_attempts,
);
)
.with_bridge_channels(event_tx, envelope_rx);
let running = server::run_stream(Arc::clone(&self.config), stream, handler).await?;
let handle = running.handle();
@@ -548,6 +600,8 @@ impl SshInterface {
Ok(SshSession {
handle,
_join: join,
event_rx,
envelope_tx,
})
}
}
@@ -576,6 +630,8 @@ impl StreamInterface for SshInterface {
pub struct SshSession {
handle: server::Handle,
_join: tokio::task::JoinHandle<()>,
event_rx: mpsc::Receiver<InterfaceEvent>,
envelope_tx: mpsc::Sender<EventEnvelope>,
}
impl SshSession {
@@ -586,26 +642,95 @@ impl SshSession {
#[async_trait]
impl InterfaceSession for SshSession {
/// Stub for Phase 1 — always returns `None`.
///
/// TODO: Bridge `alknet-control:0` channel events to call protocol
/// `InterfaceEvent` frames. Planned for Phase 2/3.
async fn recv(&mut self) -> Option<InterfaceEvent> {
None
self.event_rx.recv().await
}
/// Stub for Phase 1 — accepts silently and discards.
///
/// TODO: Bridge outgoing `EventEnvelope` frames to the SSH channel
/// established by the call protocol. Planned for Phase 2/3.
async fn send(&mut self, _envelope: EventEnvelope) -> Result<()> {
Ok(())
async fn send(&mut self, envelope: EventEnvelope) -> Result<()> {
self.envelope_tx
.send(envelope)
.await
.map_err(|_| anyhow::anyhow!("control channel bridge closed"))
}
}
async fn run_control_channel_bridge<R, W>(
read_half: R,
write_half: W,
identity: Option<Identity>,
event_tx: mpsc::Sender<InterfaceEvent>,
mut envelope_rx: mpsc::Receiver<EventEnvelope>,
) where
R: tokio::io::AsyncRead + Unpin,
W: tokio::io::AsyncWrite + Unpin,
{
let mut reader = FrameFramedReader::new(read_half);
let mut writer = FrameFramedWriter::new(write_half);
loop {
tokio::select! {
frame = reader.read_frame() => {
match frame {
Ok(Some(envelope)) => {
let event = match &identity {
Some(id) => InterfaceEvent::with_identity(envelope, id.clone()),
None => InterfaceEvent::new(envelope),
};
if event_tx.send(event).await.is_err() {
return;
}
}
Ok(None) => return,
Err(_) => return,
}
}
envelope = envelope_rx.recv() => {
match envelope {
Some(envelope) => {
if writer.write_frame(&envelope).await.is_err() {
return;
}
}
None => return,
}
}
}
}
}
pub struct ControlChannelBridge {
identity: Option<Identity>,
}
impl ControlChannelBridge {
pub fn new(identity: Option<Identity>) -> Self {
Self { identity }
}
}
#[async_trait]
impl ControlChannelHandler for ControlChannelBridge {
async fn handle_channel(&self, stream: Box<dyn DuplexStream>) {
let (event_tx, _event_rx) = mpsc::channel::<InterfaceEvent>(256);
let (_envelope_tx, envelope_rx) = mpsc::channel::<EventEnvelope>(256);
let identity = self.identity.clone();
let (read_half, write_half) = tokio::io::split(stream);
tokio::spawn(run_control_channel_bridge(
read_half,
write_half,
identity,
event_tx,
envelope_rx,
));
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::call::frame::{FrameFramedReader, FrameFramedWriter};
use tokio::io::duplex;
#[test]
fn ssh_interface_constructs_with_config() {
@@ -742,4 +867,116 @@ mod tests {
let result = iface.accept(stream, &raw_config).await;
assert!(result.is_err());
}
#[tokio::test]
async fn ssh_session_round_trip_event_envelope() {
let (client, server) = duplex(4096);
let (event_tx, mut event_rx) = mpsc::channel::<InterfaceEvent>(256);
let (envelope_tx, envelope_rx) = mpsc::channel::<EventEnvelope>(256);
let identity = Identity {
id: "SHA256:test".to_string(),
scopes: vec![],
resources: std::collections::HashMap::new(),
};
let identity_clone = identity.clone();
let (server_read, server_write) = tokio::io::split(server);
tokio::spawn(run_control_channel_bridge(
server_read,
server_write,
Some(identity_clone),
event_tx,
envelope_rx,
));
let (client_read, client_write) = tokio::io::split(client);
let mut client_reader = FrameFramedReader::new(client_read);
let mut client_writer = FrameFramedWriter::new(client_write);
let envelope = EventEnvelope::call_requested("req-1", serde_json::json!({"op": "test"}));
client_writer.write_frame(&envelope).await.unwrap();
let received_event =
tokio::time::timeout(std::time::Duration::from_secs(2), event_rx.recv())
.await
.unwrap()
.unwrap();
assert_eq!(received_event.envelope, envelope);
assert_eq!(received_event.identity.as_ref().unwrap().id, "SHA256:test");
let response = EventEnvelope::call_responded("req-1", serde_json::json!({"result": 42}));
envelope_tx.send(response.clone()).await.unwrap();
let read_back = tokio::time::timeout(
std::time::Duration::from_secs(2),
client_reader.read_frame(),
)
.await
.unwrap()
.unwrap()
.unwrap();
assert_eq!(read_back, response);
}
#[tokio::test]
async fn ssh_session_recv_without_identity() {
let (client, server) = duplex(4096);
let (event_tx, mut event_rx) = mpsc::channel::<InterfaceEvent>(256);
let (_envelope_tx, envelope_rx) = mpsc::channel::<EventEnvelope>(256);
let (server_read, server_write) = tokio::io::split(server);
tokio::spawn(run_control_channel_bridge(
server_read,
server_write,
None,
event_tx,
envelope_rx,
));
let (client_read, client_write) = tokio::io::split(client);
let mut client_writer = FrameFramedWriter::new(client_write);
let _client_reader = FrameFramedReader::new(client_read);
let envelope = EventEnvelope::call_requested("req-2", serde_json::json!({"op": "no-id"}));
client_writer.write_frame(&envelope).await.unwrap();
let received_event =
tokio::time::timeout(std::time::Duration::from_secs(2), event_rx.recv())
.await
.unwrap()
.unwrap();
assert_eq!(received_event.envelope, envelope);
assert!(received_event.identity.is_none());
}
#[tokio::test]
async fn control_channel_router_with_handler_routes_data() {
let called = std::sync::Arc::new(std::sync::atomic::AtomicBool::new(false));
let called_clone = called.clone();
struct TrackingHandler {
called: std::sync::Arc<std::sync::atomic::AtomicBool>,
}
#[async_trait]
impl ControlChannelHandler for TrackingHandler {
async fn handle_channel(&self, _stream: Box<dyn DuplexStream>) {
self.called.store(true, std::sync::atomic::Ordering::SeqCst);
}
}
let router = ControlChannelRouter::with_handler(Box::new(TrackingHandler {
called: called_clone,
}));
assert!(router.has_handler());
let (_client, server) = duplex(64);
let stream: Box<dyn DuplexStream> = Box::new(server);
let result = router.route(stream).await;
assert!(result.is_ok());
assert!(called.load(std::sync::atomic::Ordering::SeqCst));
}
}

View File

@@ -60,6 +60,10 @@ impl ControlChannelRouter {
)),
}
}
pub fn take_handler(&mut self) -> Option<Box<dyn ControlChannelHandler>> {
self.handler.take()
}
}
#[cfg(test)]