Crate aws_ssm_bridge 

A Rust implementation of the AWS Systems Manager Session Manager protocol.

The official session-manager-plugin is a CLI binary. This is a library: open sessions, stream bytes, and forward ports from inside your own async application, with no subprocess and no plugin to install.

use aws_ssm_bridge::SessionBuilder;
use futures_util::StreamExt;

let session = SessionBuilder::new("i-0123456789abcdef0").start().await?;
session.wait_ready().await?;

let mut output = session.output();
session.send(&b"uname -a\r"[..]).await?;

while let Some(chunk) = output.next().await {
    print!("{}", String::from_utf8_lossy(&chunk));
}
session.terminate().await?;

What you get

Capability	Where
Shell and command sessions	Session, documents
TCP port forwarding (smux-multiplexed)	PortForwarder
End-to-end KMS session encryption	crypto (feature kms)
Interactive terminal	InteractiveShell (feature interactive)
Automatic reconnection	ReconnectingSession
Many concurrent sessions	SessionPool
Metrics hooks	metrics

Session lifetime

A Session is either running or closed, and every way it can end — terminate, the agent hanging up, a dead network, a protocol violation — resolves Session::closed and records a CloseReason. Build on that signal rather than polling:

tokio::select! {
    () = session.closed() => {
        eprintln!("session ended: {}", session.close_reason().unwrap());
    }
    _ = do_work(&session) => {}
}

Ordering and delivery

The protocol layer handles sequencing, acknowledgement, retransmission and reordering, so Session::send and Session::output behave like an ordered, lossless byte stream. Message boundaries are an artefact of chunking and carry no meaning.

Feature flags

Feature	Default	Effect
interactive	yes	terminal and InteractiveShell; pulls in crossterm
kms	yes	KMS session encryption; pulls in aws-sdk-kms and aes-gcm
python	no	PyO3 bindings
extension-module	no	Link the bindings as a Python extension module; set by maturin

Without kms, a session whose account requires encrypted sessions fails the handshake with an explicit error rather than downgrading to plaintext.

extension-module is separate from python because it leaves the CPython symbols for the interpreter to resolve at load time: correct for a wheel, fatal for a test binary. --all-features therefore does not link; name the features you want.

Not affiliated with AWS

This is an independent implementation, not endorsed by or sponsored by Amazon Web Services, Inc.

Re-exports

pub use builder::SessionBuilder;

pub use documents::SessionType;

pub use documents::SsmDocument;

pub use errors::Error;

pub use errors::Result;

pub use metrics::MetricsRecorder;

pub use mux::SmuxConfig;

pub use mux::SmuxSession;

pub use mux::SmuxStream;

pub use pool::PoolConfig;

pub use pool::PoolStats;

pub use pool::SessionPool;

pub use port_forward::PortForwardConfig;

pub use port_forward::PortForwarder;

pub use reconnect::ReconnectConfig;

pub use reconnect::ReconnectEvent;

pub use reconnect::ReconnectingSession;

pub use session::CloseReason;

pub use session::DocumentSpec;

pub use session::Session;

pub use session::SessionConfig;

pub use session::SessionManager;

pub use shutdown::install_signal_handlers;

pub use shutdown::ShutdownSignal;

pub use interactive::InteractiveConfig;

pub use interactive::InteractiveShell;

pub use terminal::TerminalSize;

Modules

ack

Reliable delivery: acknowledgements, retransmission and RTT estimation.

binary_protocol

The AWS SSM Session Manager binary wire format.

builder

Fluent construction of sessions.

crypto

KMS session encryption (AES-256-GCM).

documents

Typed wrappers for the AWS-managed Session Manager documents.

errors

Error types for aws-ssm-bridge.

handshake

The SSM agent handshake.

interactive

A complete interactive shell, terminal and all.

metrics

Optional metrics hooks.

mux

smux v1 stream multiplexing over one SSM data channel.

pool

Managing many concurrent sessions.

port_forward

Local TCP port forwarding over an SSM session.

reconnect

A session that rebuilds itself when the connection drops.

session

Session lifecycle: starting, using and ending an SSM session.

shutdown

Cooperative cancellation for long-running session work.

terminal

Terminal plumbing for interactive sessions.

Structs

OutputStream

A borrowed view of the session’s output stream.

Enums

EndpointPolicy

Which WebSocket endpoints the client is willing to connect to.

Constants

VERSION

The version of this crate.