914 lines
32 KiB
Rust
914 lines
32 KiB
Rust
use std::borrow::Cow;
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use std::collections::HashMap;
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use std::fs;
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use std::sync::Arc;
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use base64::engine::general_purpose::STANDARD as BASE64_STANDARD;
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use base64::Engine;
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use russh::client::{self, Config, Handle};
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use russh::keys::agent::{client::AgentClient, AgentIdentity};
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use russh::keys::{decode_secret_key, key::PrivateKeyWithHashAlg, PrivateKey};
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use russh::{kex, ChannelMsg, Preferred};
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use tokio::io::{AsyncReadExt, AsyncWriteExt};
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use tokio::net::TcpListener;
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use tokio::sync::Mutex;
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use tokio::task::JoinHandle;
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use tokio::time::{Duration, MissedTickBehavior};
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use crate::models::connection::SshTunnelConfig;
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use super::file_validator::validate_file_path;
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/// Initial delay between SSH reconnect attempts.
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const INITIAL_RECONNECT_DELAY: Duration = Duration::from_secs(5);
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/// Maximum delay for exponential backoff.
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const MAX_RECONNECT_DELAY: Duration = Duration::from_secs(60);
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/// Maximum number of consecutive reconnect attempts before giving up.
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const MAX_RECONNECT_ATTEMPTS: u32 = 10;
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/// How often an idle local listener verifies that the SSH session still answers.
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const IDLE_SESSION_CHECK_INTERVAL: Duration = Duration::from_secs(30);
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/// Maximum time to wait for an explicit SSH ping response.
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const IDLE_SESSION_PING_TIMEOUT: Duration = Duration::from_secs(10);
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struct SshClient;
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impl client::Handler for SshClient {
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type Error = russh::Error;
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async fn check_server_key(
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&mut self,
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_server_public_key: &russh::keys::ssh_key::PublicKey,
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) -> Result<bool, Self::Error> {
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Ok(true)
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}
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}
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fn ssh_client_config() -> Config {
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let mut preferred = Preferred::default();
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let mut kex = preferred.kex.into_owned();
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for algorithm in [kex::ECDH_SHA2_NISTP256, kex::ECDH_SHA2_NISTP384, kex::ECDH_SHA2_NISTP521, kex::DH_G14_SHA1] {
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if !kex.contains(&algorithm) {
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kex.push(algorithm);
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}
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}
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preferred.kex = Cow::Owned(kex);
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Config { nodelay: true, keepalive_interval: Some(Duration::from_secs(30)), preferred, ..Default::default() }
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}
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#[allow(clippy::too_many_arguments)]
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async fn connect_and_authenticate(
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ssh_host: &str,
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ssh_port: u16,
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ssh_user: &str,
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ssh_password: &str,
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ssh_key_path: &str,
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ssh_key_passphrase: &str,
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use_ssh_agent: bool,
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ssh_agent_sock_path: &str,
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connect_timeout_secs: u64,
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) -> Result<Handle<SshClient>, String> {
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let config = Arc::new(ssh_client_config());
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let connect_timeout = Duration::from_secs(connect_timeout_secs);
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let mut session =
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tokio::time::timeout(connect_timeout, client::connect(config, (ssh_host, ssh_port), SshClient {}))
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.await
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.map_err(|_| format!("SSH connection timed out ({connect_timeout_secs}s)"))?
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.map_err(|e| format!("SSH connection failed: {e}"))?;
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if !ssh_key_path.is_empty() {
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// Validate SSH key file path
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validate_file_path(ssh_key_path, |_| false)?;
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let passphrase = if ssh_key_passphrase.is_empty() { None } else { Some(ssh_key_passphrase) };
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let key_pair =
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load_ssh_private_key(ssh_key_path, passphrase).map_err(|e| format!("Failed to load SSH key: {e}"))?;
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let auth_res = tokio::time::timeout(
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connect_timeout,
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session.authenticate_publickey(
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ssh_user,
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PrivateKeyWithHashAlg::new(
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Arc::new(key_pair),
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session.best_supported_rsa_hash().await.ok().flatten().flatten(),
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),
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),
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)
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.await
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.map_err(|_| format!("SSH key auth timed out ({connect_timeout_secs}s)"))?
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.map_err(|e| format!("SSH key auth failed: {e}"))?;
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if !auth_res.success() {
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return Err("SSH public key authentication failed".to_string());
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}
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} else if !ssh_password.is_empty() {
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let auth_res = tokio::time::timeout(connect_timeout, session.authenticate_password(ssh_user, ssh_password))
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.await
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.map_err(|_| format!("SSH password auth timed out ({connect_timeout_secs}s)"))?
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.map_err(|e| format!("SSH password auth failed: {e}"))?;
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if !auth_res.success() {
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return Err("SSH password authentication failed".to_string());
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}
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} else if use_ssh_agent {
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match try_authenticate_with_agent(&mut session, ssh_user, ssh_agent_sock_path, &connect_timeout).await {
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Ok(()) => {}
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Err(agent_err) => return Err(agent_err),
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}
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} else {
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return Err("No SSH authentication method provided (password, key, or ssh-agent)".to_string());
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}
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Ok(session)
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}
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/// Try to authenticate using ssh-agent identities. Returns `Ok(())` on success,
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/// or an error describing why agent auth failed (unavailable, no identities, all rejected).
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async fn try_authenticate_with_agent(
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session: &mut Handle<SshClient>,
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ssh_user: &str,
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ssh_agent_sock_path: &str,
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connect_timeout: &Duration,
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) -> Result<(), String> {
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#[cfg(unix)]
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let mut agent = if ssh_agent_sock_path.is_empty() {
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match AgentClient::connect_env().await {
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Ok(a) => a,
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Err(e) => {
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return Err(format!("No SSH password or key provided, and ssh-agent is unavailable: {e}"));
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}
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}
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} else {
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match AgentClient::connect_uds(ssh_agent_sock_path).await {
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Ok(a) => a,
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Err(e) => {
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return Err(format!(
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"No SSH password or key provided, and ssh-agent at '{}' is unavailable: {e}",
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ssh_agent_sock_path
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));
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}
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}
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};
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#[cfg(windows)]
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let mut agent = {
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let stream = pageant::PageantStream::new()
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.await
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.map_err(|e| format!("No SSH password or key provided, and ssh-agent (Pageant) is unavailable: {e}"))?;
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AgentClient::connect(stream)
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};
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let identities = match agent.request_identities().await {
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Ok(ids) if ids.is_empty() => {
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return Err("No SSH password or key provided, and ssh-agent has no identities".to_string());
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}
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Ok(ids) => ids,
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Err(e) => {
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return Err(format!("No SSH password or key provided, and ssh-agent request failed: {e}"));
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}
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};
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let hash_alg = session.best_supported_rsa_hash().await.ok().flatten().flatten();
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let auth_result = tokio::time::timeout(*connect_timeout, async {
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for identity in identities {
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let result = match &identity {
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AgentIdentity::PublicKey { key, .. } => {
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session.authenticate_publickey_with(ssh_user, key.clone(), hash_alg, &mut agent).await
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}
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AgentIdentity::Certificate { certificate, .. } => {
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session.authenticate_certificate_with(ssh_user, certificate.clone(), hash_alg, &mut agent).await
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}
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};
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match result {
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Ok(auth_res) if auth_res.success() => return Ok(()),
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Ok(_) => continue,
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Err(e) => {
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log::debug!("SSH agent identity ({}) auth failed: {e}", identity.comment());
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continue;
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}
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}
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}
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Err("No SSH password or key provided, and no ssh-agent identity was accepted".to_string())
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})
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.await;
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match auth_result {
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Ok(Ok(())) => Ok(()),
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Ok(Err(e)) => Err(e),
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Err(_) => Err("No SSH password or key provided, and ssh-agent auth timed out".to_string()),
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}
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}
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fn load_ssh_private_key(path: &str, passphrase: Option<&str>) -> Result<PrivateKey, String> {
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let secret = fs::read_to_string(path).map_err(|e| e.to_string())?;
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match decode_secret_key(&secret, passphrase) {
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Ok(key) => Ok(key),
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Err(err) if is_ssh_key_character_encoding_error(&err.to_string()) => {
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let sanitized = sanitize_unencrypted_openssh_comment(&secret)?;
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decode_secret_key(&sanitized, passphrase).map_err(|retry_err| retry_err.to_string())
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}
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Err(err) => Err(err.to_string()),
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}
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}
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fn is_ssh_key_character_encoding_error(error: &str) -> bool {
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error.contains("SshKey: character encoding invalid")
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}
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fn sanitize_unencrypted_openssh_comment(secret: &str) -> Result<String, String> {
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const BEGIN: &str = "-----BEGIN OPENSSH PRIVATE KEY-----";
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const END: &str = "-----END OPENSSH PRIVATE KEY-----";
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if !secret.lines().any(|line| line == BEGIN) {
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return Err("SSH key comment encoding is invalid and the key is not an OpenSSH private key".to_string());
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}
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let body = secret.lines().filter(|line| !line.starts_with("-----")).collect::<String>();
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let mut bytes =
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BASE64_STANDARD.decode(body.as_bytes()).map_err(|e| format!("OpenSSH key base64 decode failed: {e}"))?;
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sanitize_unencrypted_openssh_comment_bytes(&mut bytes)?;
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Ok(format!("{BEGIN}\n{}\n{END}\n", BASE64_STANDARD.encode(bytes)))
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}
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fn sanitize_unencrypted_openssh_comment_bytes(bytes: &mut Vec<u8>) -> Result<(), String> {
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const AUTH_MAGIC: &[u8] = b"openssh-key-v1\0";
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if !bytes.starts_with(AUTH_MAGIC) {
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return Err("OpenSSH key header is invalid".to_string());
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}
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let mut pos = AUTH_MAGIC.len();
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let ciphername = read_ssh_string(bytes, &mut pos)?;
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if ciphername != b"none" {
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return Err("SSH key comment encoding is invalid and encrypted OpenSSH keys cannot be sanitized".to_string());
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}
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let _kdfname = read_ssh_string(bytes, &mut pos)?;
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let _kdfoptions = read_ssh_string(bytes, &mut pos)?;
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let key_count = read_u32(bytes, &mut pos)?;
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if key_count != 1 {
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return Err("OpenSSH keys with multiple private keys are unsupported".to_string());
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}
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let _public_key = read_ssh_string(bytes, &mut pos)?;
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let private_blob_len_pos = pos;
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let private_blob = read_ssh_string(bytes, &mut pos)?;
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let patched_private_blob = sanitize_private_blob_comment(private_blob)?;
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let patched_private_blob_len = (patched_private_blob.len() as u32).to_be_bytes();
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bytes.splice(private_blob_len_pos..pos, patched_private_blob_len.into_iter().chain(patched_private_blob));
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Ok(())
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}
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fn sanitize_private_blob_comment(blob: &[u8]) -> Result<Vec<u8>, String> {
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let unpadded_end = blob
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.len()
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.checked_sub(openssh_padding_len(blob)?)
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.ok_or_else(|| "OpenSSH private key padding is invalid".to_string())?;
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let comment_len_pos = find_trailing_ssh_string_len_pos(&blob[..unpadded_end])
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.ok_or_else(|| "OpenSSH private key comment field was not found".to_string())?;
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let mut patched = Vec::with_capacity(blob.len());
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patched.extend_from_slice(&blob[..comment_len_pos]);
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patched.extend_from_slice(&0u32.to_be_bytes());
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let padding_len = padding_len_for_block(patched.len(), 8);
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for value in 1..=padding_len {
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patched.push(value as u8);
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}
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Ok(patched)
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}
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fn openssh_padding_len(bytes: &[u8]) -> Result<usize, String> {
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for len in (1..=16).rev() {
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if bytes.len() >= len
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&& bytes[bytes.len() - len..].iter().enumerate().all(|(index, byte)| *byte == (index + 1) as u8)
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{
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return Ok(len);
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}
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}
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Err("OpenSSH private key padding is invalid".to_string())
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}
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fn find_trailing_ssh_string_len_pos(bytes: &[u8]) -> Option<usize> {
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(8..bytes.len().saturating_sub(3)).rev().find(|pos| {
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let Some(len_bytes) = bytes.get(*pos..*pos + 4) else {
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return false;
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};
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let len = u32::from_be_bytes(len_bytes.try_into().expect("slice length checked")) as usize;
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pos.checked_add(4).and_then(|value| value.checked_add(len)) == Some(bytes.len())
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})
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}
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fn padding_len_for_block(len: usize, block_size: usize) -> usize {
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let remainder = len % block_size;
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if remainder == 0 {
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block_size
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} else {
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block_size - remainder
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}
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}
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fn read_ssh_string<'a>(bytes: &'a [u8], pos: &mut usize) -> Result<&'a [u8], String> {
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let len = read_u32(bytes, pos)? as usize;
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let end = pos.checked_add(len).ok_or_else(|| "OpenSSH key field length is invalid".to_string())?;
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if end > bytes.len() {
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return Err("OpenSSH key field is truncated".to_string());
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}
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let value = &bytes[*pos..end];
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*pos = end;
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Ok(value)
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}
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fn read_u32(bytes: &[u8], pos: &mut usize) -> Result<u32, String> {
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let end = pos.checked_add(4).ok_or_else(|| "OpenSSH key field length is invalid".to_string())?;
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let value = bytes.get(*pos..end).ok_or_else(|| "OpenSSH key field is truncated".to_string())?;
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*pos = end;
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Ok(u32::from_be_bytes(value.try_into().map_err(|_| "OpenSSH key field length is invalid".to_string())?))
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}
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/// Accept connections on the local listener and forward them through the SSH session.
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/// Returns when the SSH session dies (listener error or session.is_closed()).
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async fn forward_loop(session: &Handle<SshClient>, listener: &TcpListener, remote_host: &str, remote_port: u16) {
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let mut idle_check = tokio::time::interval(IDLE_SESSION_CHECK_INTERVAL);
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idle_check.set_missed_tick_behavior(MissedTickBehavior::Delay);
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loop {
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let accepted = tokio::select! {
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result = listener.accept() => result,
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_ = idle_check.tick() => {
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if session.is_closed() {
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log::warn!("SSH session closed while tunnel was idle");
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break;
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}
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match tokio::time::timeout(IDLE_SESSION_PING_TIMEOUT, session.send_ping()).await {
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Ok(Ok(())) => continue,
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Ok(Err(e)) => {
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log::warn!("SSH idle ping failed: {e}");
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break;
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}
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Err(_) => {
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log::warn!("SSH idle ping timed out");
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break;
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}
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}
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}
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};
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let (mut stream, peer_addr) = match accepted {
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Ok(v) => v,
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Err(e) => {
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log::error!("SSH tunnel listener error: {e}");
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break;
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}
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};
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|
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// Check session health before opening a new channel
|
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if session.is_closed() {
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log::warn!("SSH session closed, exiting forward loop");
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break;
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}
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|
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let mut channel = match session
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.channel_open_direct_tcpip(
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remote_host,
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remote_port.into(),
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peer_addr.ip().to_string(),
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peer_addr.port().into(),
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)
|
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.await
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{
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Ok(c) => c,
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Err(e) => {
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log::error!("SSH direct-tcpip failed: {e}");
|
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break;
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}
|
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};
|
|
|
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tokio::spawn(async move {
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let mut buf = vec![0u8; 65536];
|
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let mut stream_closed = false;
|
|
|
|
loop {
|
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tokio::select! {
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r = stream.read(&mut buf), if !stream_closed => {
|
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match r {
|
|
Ok(0) => {
|
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stream_closed = true;
|
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let _ = channel.eof().await;
|
|
}
|
|
Ok(n) => {
|
|
if channel.data(&buf[..n]).await.is_err() {
|
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break;
|
|
}
|
|
}
|
|
Err(_) => break,
|
|
}
|
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}
|
|
msg = channel.wait() => {
|
|
match msg {
|
|
Some(ChannelMsg::Data { ref data }) => {
|
|
if stream.write_all(data).await.is_err() {
|
|
break;
|
|
}
|
|
}
|
|
Some(ChannelMsg::Eof) | None => break,
|
|
_ => {}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
});
|
|
}
|
|
}
|
|
|
|
/// Main tunnel task: runs the forward loop and automatically reconnects
|
|
/// the SSH session when it drops. The local TcpListener survives across
|
|
/// reconnections so the tunnel appears continuously available to clients.
|
|
/// Uses exponential backoff for reconnect attempts and gives up after
|
|
/// MAX_RECONNECT_ATTEMPTS to avoid log storms from permanent failures.
|
|
#[allow(clippy::too_many_arguments)]
|
|
async fn tunnel_reconnect_loop(
|
|
mut session: Handle<SshClient>,
|
|
connect_host: String,
|
|
connect_port: u16,
|
|
ssh_user: String,
|
|
ssh_password: String,
|
|
ssh_key_path: String,
|
|
ssh_key_passphrase: String,
|
|
use_ssh_agent: bool,
|
|
ssh_agent_sock_path: String,
|
|
connect_timeout_secs: u64,
|
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listener: TcpListener,
|
|
remote_host: String,
|
|
remote_port: u16,
|
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) {
|
|
loop {
|
|
log::info!("SSH tunnel active: {}:{} -> {}:{}", connect_host, connect_port, remote_host, remote_port);
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|
|
|
forward_loop(&session, &listener, &remote_host, remote_port).await;
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|
|
|
log::warn!("SSH tunnel connection lost ({}:{}), reconnecting...", connect_host, connect_port);
|
|
|
|
// Reconnect with exponential backoff
|
|
let mut delay = INITIAL_RECONNECT_DELAY;
|
|
let mut attempts: u32 = 0;
|
|
|
|
loop {
|
|
if attempts >= MAX_RECONNECT_ATTEMPTS {
|
|
log::error!(
|
|
"SSH tunnel ({connect_host}:{connect_port}): max reconnect attempts ({MAX_RECONNECT_ATTEMPTS}) exhausted, giving up"
|
|
);
|
|
return;
|
|
}
|
|
|
|
tokio::time::sleep(delay).await;
|
|
|
|
match connect_and_authenticate(
|
|
&connect_host,
|
|
connect_port,
|
|
&ssh_user,
|
|
&ssh_password,
|
|
&ssh_key_path,
|
|
&ssh_key_passphrase,
|
|
use_ssh_agent,
|
|
&ssh_agent_sock_path,
|
|
connect_timeout_secs,
|
|
)
|
|
.await
|
|
{
|
|
Ok(new_session) => {
|
|
session = new_session;
|
|
log::info!(
|
|
"SSH tunnel reconnected to {}:{} (attempt {})",
|
|
connect_host,
|
|
connect_port,
|
|
attempts + 1
|
|
);
|
|
break;
|
|
}
|
|
Err(e) => {
|
|
attempts += 1;
|
|
log::error!(
|
|
"SSH reconnect failed ({}:{}, attempt {attempts}/{MAX_RECONNECT_ATTEMPTS}): {e}",
|
|
connect_host,
|
|
connect_port,
|
|
);
|
|
// Exponential backoff: double the delay, cap at MAX_RECONNECT_DELAY
|
|
delay = std::cmp::min(delay * 2, MAX_RECONNECT_DELAY);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
struct TunnelEntry {
|
|
handles: Vec<JoinHandle<()>>,
|
|
local_port: u16,
|
|
}
|
|
|
|
#[cfg(test)]
|
|
#[derive(Debug, Clone, PartialEq, Eq)]
|
|
struct PlannedTunnel {
|
|
connect_host: String,
|
|
connect_port: u16,
|
|
remote_host: String,
|
|
remote_port: u16,
|
|
}
|
|
|
|
pub struct TunnelManager {
|
|
tunnels: Mutex<HashMap<String, TunnelEntry>>,
|
|
}
|
|
|
|
impl Default for TunnelManager {
|
|
fn default() -> Self {
|
|
Self::new()
|
|
}
|
|
}
|
|
|
|
impl TunnelManager {
|
|
pub fn new() -> Self {
|
|
Self { tunnels: Mutex::new(HashMap::new()) }
|
|
}
|
|
|
|
#[allow(clippy::too_many_arguments)]
|
|
pub async fn start_tunnel(
|
|
&self,
|
|
connection_id: &str,
|
|
ssh_host: &str,
|
|
ssh_port: u16,
|
|
ssh_user: &str,
|
|
ssh_password: &str,
|
|
ssh_key_path: &str,
|
|
ssh_key_passphrase: &str,
|
|
use_ssh_agent: bool,
|
|
ssh_agent_sock_path: &str,
|
|
connect_timeout_secs: u64,
|
|
remote_host: &str,
|
|
remote_port: u16,
|
|
expose_to_lan: bool,
|
|
) -> Result<u16, String> {
|
|
// Check cache under lock to avoid race with concurrent callers.
|
|
// Also evict stale entries whose background task has exited.
|
|
{
|
|
let mut tunnels = self.tunnels.lock().await;
|
|
if let Some(port) = Self::get_active_port(&mut tunnels, connection_id) {
|
|
return Ok(port);
|
|
}
|
|
}
|
|
// Slow SSH connection — do this outside the lock.
|
|
let (handle, local_port) = spawn_tunnel(
|
|
ssh_host,
|
|
ssh_port,
|
|
ssh_user,
|
|
ssh_password,
|
|
ssh_key_path,
|
|
ssh_key_passphrase,
|
|
use_ssh_agent,
|
|
ssh_agent_sock_path,
|
|
connect_timeout_secs,
|
|
remote_host,
|
|
remote_port,
|
|
expose_to_lan,
|
|
)
|
|
.await?;
|
|
|
|
// Re-check under lock: another caller may have beaten us.
|
|
let mut tunnels = self.tunnels.lock().await;
|
|
if let Some(port) = Self::get_active_port(&mut tunnels, connection_id) {
|
|
// Another task already created a live tunnel; abort ours.
|
|
handle.abort();
|
|
return Ok(port);
|
|
}
|
|
tunnels.insert(connection_id.to_string(), TunnelEntry { handles: vec![handle], local_port });
|
|
Ok(local_port)
|
|
}
|
|
|
|
/// Returns the local port for a cached tunnel entry, or `None` if the entry
|
|
/// is stale (all background handles have exited).
|
|
fn get_active_port(tunnels: &mut HashMap<String, TunnelEntry>, connection_id: &str) -> Option<u16> {
|
|
let entry = tunnels.get(connection_id)?;
|
|
if entry.handles.iter().all(|h| h.is_finished()) {
|
|
tunnels.remove(connection_id);
|
|
return None;
|
|
}
|
|
Some(entry.local_port)
|
|
}
|
|
|
|
pub async fn start_chain(
|
|
&self,
|
|
connection_id: &str,
|
|
hops: &[SshTunnelConfig],
|
|
remote_host: &str,
|
|
remote_port: u16,
|
|
) -> Result<u16, String> {
|
|
if hops.is_empty() {
|
|
return Err("No SSH tunnel hops configured".to_string());
|
|
}
|
|
// Check cache under lock; evict stale entries.
|
|
{
|
|
let mut tunnels = self.tunnels.lock().await;
|
|
if let Some(port) = Self::get_active_port(&mut tunnels, connection_id) {
|
|
return Ok(port);
|
|
}
|
|
}
|
|
|
|
let mut handles = Vec::new();
|
|
let mut next_connect_endpoint: Option<(String, u16)> = None;
|
|
let mut final_local_port = 0;
|
|
|
|
for (index, hop) in hops.iter().enumerate() {
|
|
let is_last = index + 1 == hops.len();
|
|
let (connect_host, connect_port) =
|
|
next_connect_endpoint.clone().unwrap_or_else(|| (hop.host.clone(), hop.port));
|
|
let (target_host, target_port) = if is_last {
|
|
(remote_host.to_string(), remote_port)
|
|
} else {
|
|
(hops[index + 1].host.clone(), hops[index + 1].port)
|
|
};
|
|
|
|
let (handle, local_port) = spawn_tunnel(
|
|
&connect_host,
|
|
connect_port,
|
|
&hop.user,
|
|
&hop.password,
|
|
&hop.key_path,
|
|
&hop.key_passphrase,
|
|
hop.use_ssh_agent,
|
|
&hop.ssh_agent_sock_path,
|
|
effective_hop_timeout(hop),
|
|
&target_host,
|
|
target_port,
|
|
is_last && hop.expose_lan,
|
|
)
|
|
.await
|
|
.map_err(|err| format!("SSH hop {} failed: {err}", index + 1))?;
|
|
|
|
handles.push(handle);
|
|
final_local_port = local_port;
|
|
next_connect_endpoint = Some(("127.0.0.1".to_string(), local_port));
|
|
}
|
|
|
|
// Re-check under lock: another caller may have beaten us.
|
|
let mut tunnels = self.tunnels.lock().await;
|
|
if let Some(port) = Self::get_active_port(&mut tunnels, connection_id) {
|
|
for handle in handles {
|
|
handle.abort();
|
|
}
|
|
return Ok(port);
|
|
}
|
|
tunnels.insert(connection_id.to_string(), TunnelEntry { handles, local_port: final_local_port });
|
|
Ok(final_local_port)
|
|
}
|
|
|
|
pub async fn local_port(&self, connection_id: &str) -> Option<u16> {
|
|
self.tunnels.lock().await.get(connection_id).map(|entry| entry.local_port)
|
|
}
|
|
|
|
pub async fn stop_tunnel(&self, connection_id: &str) {
|
|
if let Some(entry) = self.tunnels.lock().await.remove(connection_id) {
|
|
for handle in entry.handles {
|
|
handle.abort();
|
|
}
|
|
}
|
|
}
|
|
|
|
pub async fn stop_tunnels_with_prefix(&self, connection_id_prefix: &str) {
|
|
let mut tunnels = self.tunnels.lock().await;
|
|
let keys: Vec<String> = tunnels.keys().filter(|key| key.starts_with(connection_id_prefix)).cloned().collect();
|
|
for key in keys {
|
|
if let Some(entry) = tunnels.remove(&key) {
|
|
for handle in entry.handles {
|
|
handle.abort();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
#[allow(clippy::too_many_arguments)]
|
|
async fn spawn_tunnel(
|
|
connect_host: &str,
|
|
connect_port: u16,
|
|
ssh_user: &str,
|
|
ssh_password: &str,
|
|
ssh_key_path: &str,
|
|
ssh_key_passphrase: &str,
|
|
use_ssh_agent: bool,
|
|
ssh_agent_sock_path: &str,
|
|
connect_timeout_secs: u64,
|
|
remote_host: &str,
|
|
remote_port: u16,
|
|
expose_to_lan: bool,
|
|
) -> Result<(JoinHandle<()>, u16), String> {
|
|
let local_port = portpicker::pick_unused_port().ok_or("No available port")?;
|
|
|
|
let bind_addr = if expose_to_lan { "0.0.0.0" } else { "127.0.0.1" };
|
|
let listener =
|
|
TcpListener::bind((bind_addr, local_port)).await.map_err(|e| format!("Failed to bind local port: {e}"))?;
|
|
|
|
// Initial connection: fail fast on bad credentials
|
|
let session = connect_and_authenticate(
|
|
connect_host,
|
|
connect_port,
|
|
ssh_user,
|
|
ssh_password,
|
|
ssh_key_path,
|
|
ssh_key_passphrase,
|
|
use_ssh_agent,
|
|
ssh_agent_sock_path,
|
|
connect_timeout_secs,
|
|
)
|
|
.await?;
|
|
|
|
let handle = tokio::spawn(tunnel_reconnect_loop(
|
|
session,
|
|
connect_host.to_string(),
|
|
connect_port,
|
|
ssh_user.to_string(),
|
|
ssh_password.to_string(),
|
|
ssh_key_path.to_string(),
|
|
ssh_key_passphrase.to_string(),
|
|
use_ssh_agent,
|
|
ssh_agent_sock_path.to_string(),
|
|
connect_timeout_secs,
|
|
listener,
|
|
remote_host.to_string(),
|
|
remote_port,
|
|
));
|
|
|
|
Ok((handle, local_port))
|
|
}
|
|
|
|
fn effective_hop_timeout(hop: &SshTunnelConfig) -> u64 {
|
|
if hop.connect_timeout_secs == 0 {
|
|
crate::models::connection::default_ssh_connect_timeout_secs()
|
|
} else {
|
|
hop.connect_timeout_secs
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
fn plan_chain(
|
|
hops: &[SshTunnelConfig],
|
|
remote_host: &str,
|
|
remote_port: u16,
|
|
local_ports: &[u16],
|
|
) -> Vec<PlannedTunnel> {
|
|
let mut planned = Vec::new();
|
|
let mut next_connect_endpoint: Option<(String, u16)> = None;
|
|
for (index, hop) in hops.iter().enumerate() {
|
|
let is_last = index + 1 == hops.len();
|
|
let (connect_host, connect_port) =
|
|
next_connect_endpoint.clone().unwrap_or_else(|| (hop.host.clone(), hop.port));
|
|
let (target_host, target_port) = if is_last {
|
|
(remote_host.to_string(), remote_port)
|
|
} else {
|
|
(hops[index + 1].host.clone(), hops[index + 1].port)
|
|
};
|
|
planned.push(PlannedTunnel { connect_host, connect_port, remote_host: target_host, remote_port: target_port });
|
|
if let Some(local_port) = local_ports.get(index) {
|
|
next_connect_endpoint = Some(("127.0.0.1".to_string(), *local_port));
|
|
}
|
|
}
|
|
planned
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::{
|
|
effective_hop_timeout, openssh_padding_len, plan_chain, read_ssh_string,
|
|
sanitize_unencrypted_openssh_comment_bytes, ssh_client_config, PlannedTunnel, TunnelManager,
|
|
};
|
|
use crate::models::connection::{default_ssh_connect_timeout_secs, SshTunnelConfig};
|
|
|
|
fn push_u32(bytes: &mut Vec<u8>, value: u32) {
|
|
bytes.extend_from_slice(&value.to_be_bytes());
|
|
}
|
|
|
|
fn push_ssh_string(bytes: &mut Vec<u8>, value: &[u8]) {
|
|
push_u32(bytes, value.len() as u32);
|
|
bytes.extend_from_slice(value);
|
|
}
|
|
|
|
fn padded_private_blob(comment: &[u8]) -> Vec<u8> {
|
|
let mut blob = Vec::new();
|
|
push_u32(&mut blob, 7);
|
|
push_u32(&mut blob, 7);
|
|
blob.extend_from_slice(b"fake-private-key");
|
|
push_ssh_string(&mut blob, comment);
|
|
for value in 1..=(8 - (blob.len() % 8)) {
|
|
blob.push(value as u8);
|
|
}
|
|
blob
|
|
}
|
|
|
|
fn openssh_container(private_blob: &[u8]) -> Vec<u8> {
|
|
let mut bytes = b"openssh-key-v1\0".to_vec();
|
|
push_ssh_string(&mut bytes, b"none");
|
|
push_ssh_string(&mut bytes, b"none");
|
|
push_ssh_string(&mut bytes, b"");
|
|
push_u32(&mut bytes, 1);
|
|
push_ssh_string(&mut bytes, b"fake-public-key");
|
|
push_ssh_string(&mut bytes, private_blob);
|
|
bytes
|
|
}
|
|
|
|
fn hop(id: &str, host: &str, port: u16) -> SshTunnelConfig {
|
|
SshTunnelConfig {
|
|
id: id.to_string(),
|
|
name: String::new(),
|
|
enabled: true,
|
|
host: host.to_string(),
|
|
port,
|
|
user: "user".to_string(),
|
|
password: "secret".to_string(),
|
|
key_path: String::new(),
|
|
key_passphrase: String::new(),
|
|
connect_timeout_secs: 5,
|
|
expose_lan: false,
|
|
use_ssh_agent: false,
|
|
ssh_agent_sock_path: String::new(),
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn chain_plan_routes_each_hop_to_next_endpoint() {
|
|
let hops = vec![hop("a", "bastion-a", 22), hop("b", "bastion-b", 2200)];
|
|
|
|
let planned = plan_chain(&hops, "db.internal", 5432, &[41001, 41002]);
|
|
|
|
assert_eq!(
|
|
planned,
|
|
vec![
|
|
PlannedTunnel {
|
|
connect_host: "bastion-a".to_string(),
|
|
connect_port: 22,
|
|
remote_host: "bastion-b".to_string(),
|
|
remote_port: 2200,
|
|
},
|
|
PlannedTunnel {
|
|
connect_host: "127.0.0.1".to_string(),
|
|
connect_port: 41001,
|
|
remote_host: "db.internal".to_string(),
|
|
remote_port: 5432,
|
|
},
|
|
]
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn zero_hop_timeout_uses_default() {
|
|
let mut tunnel = hop("a", "bastion-a", 22);
|
|
tunnel.connect_timeout_secs = 0;
|
|
|
|
assert_eq!(effective_hop_timeout(&tunnel), default_ssh_connect_timeout_secs());
|
|
}
|
|
|
|
#[test]
|
|
fn ssh_client_config_keeps_legacy_kex_after_safe_defaults() {
|
|
let config = ssh_client_config();
|
|
let kex = config.preferred.kex;
|
|
let curve25519_index = kex.iter().position(|algorithm| *algorithm == russh::kex::CURVE25519).unwrap();
|
|
let ecdh_index = kex.iter().position(|algorithm| *algorithm == russh::kex::ECDH_SHA2_NISTP256).unwrap();
|
|
let group14_sha1_index = kex.iter().position(|algorithm| *algorithm == russh::kex::DH_G14_SHA1).unwrap();
|
|
|
|
assert!(curve25519_index < ecdh_index);
|
|
assert!(ecdh_index < group14_sha1_index);
|
|
}
|
|
|
|
#[test]
|
|
fn sanitizes_invalid_openssh_private_key_comment() {
|
|
let mut key = openssh_container(&padded_private_blob(&[0xff, 0xfe, b'a']));
|
|
|
|
sanitize_unencrypted_openssh_comment_bytes(&mut key).unwrap();
|
|
|
|
let mut pos = b"openssh-key-v1\0".len();
|
|
assert_eq!(read_ssh_string(&key, &mut pos).unwrap(), b"none");
|
|
let _kdfname = read_ssh_string(&key, &mut pos).unwrap();
|
|
let _kdfoptions = read_ssh_string(&key, &mut pos).unwrap();
|
|
pos += 4;
|
|
let _public_key = read_ssh_string(&key, &mut pos).unwrap();
|
|
let private_blob = read_ssh_string(&key, &mut pos).unwrap();
|
|
let unpadded_end = private_blob.len() - openssh_padding_len(private_blob).unwrap();
|
|
let comment_len_pos = unpadded_end - 4;
|
|
|
|
assert_eq!(&private_blob[comment_len_pos..unpadded_end], &0u32.to_be_bytes());
|
|
}
|
|
|
|
#[tokio::test]
|
|
async fn local_port_reuses_existing_chain_entry() {
|
|
let manager = TunnelManager::new();
|
|
|
|
assert_eq!(manager.local_port("missing").await, None);
|
|
manager.stop_tunnel("missing").await;
|
|
}
|
|
}
|