Save SSH passwords in Windows Credential Manager and auto-type at prompt

src-tauri/Cargo.toml

@@ -18,6 +18,10 @@ tauri = { version = "2", features = [] }
 tauri-plugin-clipboard-manager = "2"
 tauri-plugin-opener = "2"
 
+# Saved-credential storage (Windows Credential Manager / DPAPI).
+keyring-core = "1"
+windows-native-keyring-store = "1"
+
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 

src-tauri/src/commands.rs

@@ -3,7 +3,8 @@
 use base64::{engine::general_purpose::STANDARD as B64, Engine as _};
 use tauri::{AppHandle, Manager};
 
-use crate::hosts::{self, SshHost};
+use crate::creds;
+use crate::hosts::{self, SshHost, SshHostView};
 use crate::pty::{list_wsl_distros, PaneId, PtyManager, SpawnSpec};
 
 const WORKSPACE_FILE: &str = "workspace.json";
@@ -92,11 +93,47 @@ pub async fn load_workspace(app: AppHandle) -> Result<Option<String>, String> {
 }
 
 #[tauri::command]
-pub async fn list_ssh_hosts(app: AppHandle) -> Result<Vec<SshHost>, String> {
-    hosts::load(&app).map_err(|e| e.to_string())
+pub async fn list_ssh_hosts(app: AppHandle) -> Result<Vec<SshHostView>, String> {
+    let raw = hosts::load(&app).map_err(|e| e.to_string())?;
+    Ok(raw
+        .into_iter()
+        .map(|h| {
+            let has_password = creds::has(&h.id);
+            SshHostView { host: h, has_password }
+        })
+        .collect())
 }
 
 #[tauri::command]
 pub async fn save_ssh_hosts(app: AppHandle, hosts: Vec<SshHost>) -> Result<(), String> {
+    // Sweep orphaned credentials: any host id that existed before this call
+    // but isn't in the new list gets its keyring entry deleted. Saves the
+    // frontend from having to diff and call delete_host_password itself.
+    if let Ok(prior) = crate::hosts::load(&app) {
+        let new_ids: std::collections::HashSet<&str> =
+            hosts.iter().map(|h| h.id.as_str()).collect();
+        for old in &prior {
+            if !new_ids.contains(old.id.as_str()) {
+                if let Err(e) = creds::delete(&old.id) {
+                    tracing::warn!("orphan credential cleanup failed for {}: {e}", old.id);
+                }
+            }
+        }
+    }
     crate::hosts::save(&app, &hosts).map_err(|e| e.to_string())
 }
+
+#[tauri::command]
+pub async fn set_host_password(host_id: String, password: String) -> Result<(), String> {
+    creds::set(&host_id, &password).map_err(|e| e.to_string())
+}
+
+#[tauri::command]
+pub async fn delete_host_password(host_id: String) -> Result<(), String> {
+    creds::delete(&host_id).map_err(|e| e.to_string())
+}
+
+#[tauri::command]
+pub async fn has_host_password(host_id: String) -> Result<bool, String> {
+    Ok(creds::has(&host_id))
+}

src-tauri/src/creds.rs

@@ -0,0 +1,46 @@
+//! Saved SSH-host credentials. Backed by Windows Credential Manager via
+//! `keyring-core` + `windows-native-keyring-store` — passwords are DPAPI-
+//! encrypted at rest and scoped to the user account. Never written to
+//! disk in plaintext, never logged, never sent to the frontend.
+
+use anyhow::{Context, Result};
+use keyring_core::{Entry, Error as KeyringError};
+
+const SERVICE: &str = "tiletopia";
+
+fn target_for(host_id: &str) -> String {
+    format!("ssh-host:{host_id}")
+}
+
+fn entry(host_id: &str) -> Result<Entry> {
+    Entry::new(SERVICE, &target_for(host_id))
+        .with_context(|| format!("create keyring entry for {host_id}"))
+}
+
+pub fn set(host_id: &str, password: &str) -> Result<()> {
+    entry(host_id)?
+        .set_password(password)
+        .with_context(|| format!("write credential for {host_id}"))
+}
+
+pub fn get(host_id: &str) -> Result<Option<String>> {
+    match entry(host_id)?.get_password() {
+        Ok(p) => Ok(Some(p)),
+        Err(KeyringError::NoEntry) => Ok(None),
+        Err(e) => Err(anyhow::Error::from(e)
+            .context(format!("read credential for {host_id}"))),
+    }
+}
+
+pub fn delete(host_id: &str) -> Result<()> {
+    match entry(host_id)?.delete_credential() {
+        Ok(()) => Ok(()),
+        Err(KeyringError::NoEntry) => Ok(()),
+        Err(e) => Err(anyhow::Error::from(e)
+            .context(format!("delete credential for {host_id}"))),
+    }
+}
+
+pub fn has(host_id: &str) -> bool {
+    matches!(get(host_id), Ok(Some(_)))
+}

src-tauri/src/hosts.rs

@@ -10,6 +10,18 @@ use tauri::{AppHandle, Manager};
 
 const HOSTS_FILE: &str = "hosts.json";
 
+/// What `list_ssh_hosts` returns: the saved host plus a flag derived from
+/// keyring (true iff a password is stored under this host's id). The flag
+/// is read-only — saving a host doesn't touch the credential store. See
+/// the dedicated set/delete password commands for that.
+#[derive(Debug, Clone, Serialize)]
+pub struct SshHostView {
+    #[serde(flatten)]
+    pub host: SshHost,
+    #[serde(rename = "hasPassword")]
+    pub has_password: bool,
+}
+
 /// One saved host. Fields beyond `hostname` are optional; ssh.exe will fall
 /// back to `~/.ssh/config` and its own defaults for anything we don't pass.
 #[derive(Debug, Clone, Serialize, Deserialize)]

src-tauri/src/lib.rs

@@ -1,6 +1,7 @@
 //! Library entry point. `main.rs` calls `run()`.
 
 mod commands;
+mod creds;
 mod hosts;
 mod pty;
 
@@ -15,6 +16,16 @@ pub fn run() {
         .with_writer(std::io::stderr)
         .try_init();
 
+    // keyring-core 1.x requires explicit store registration before any
+    // Entry::new() call. We're Windows-only so the Credential Manager
+    // backend is the only choice. Failure here means SSH passwords won't
+    // be retrievable — log and continue (host configs still work without
+    // saved passwords; users just see the prompt and type it manually).
+    match windows_native_keyring_store::Store::new() {
+        Ok(store) => keyring_core::set_default_store(store),
+        Err(e) => tracing::warn!("keyring store init failed: {e}"),
+    }
+
     tauri::Builder::default()
         .plugin(tauri_plugin_clipboard_manager::init())
         .plugin(tauri_plugin_opener::init())
@@ -29,6 +40,9 @@ pub fn run() {
             commands::load_workspace,
             commands::list_ssh_hosts,
             commands::save_ssh_hosts,
+            commands::set_host_password,
+            commands::delete_host_password,
+            commands::has_host_password,
         ])
         .run(tauri::generate_context!())
         .expect("error while running tauri application");

src-tauri/src/pty.rs

@@ -5,6 +5,8 @@
 use std::collections::HashMap;
 use std::io::{Read, Write};
 use std::sync::atomic::{AtomicU64, Ordering};
+use std::sync::Arc;
+use std::time::{Duration, Instant};
 
 use anyhow::{anyhow, Context, Result};
 use base64::{engine::general_purpose::STANDARD as B64, Engine as _};
@@ -13,6 +15,8 @@ use portable_pty::{native_pty_system, CommandBuilder, MasterPty, PtySize};
 use serde::{Deserialize, Serialize};
 use tauri::{AppHandle, Emitter};
 
+use crate::creds;
+
 pub type PaneId = u64;
 
 /// Discriminated union describing what to spawn into a fresh PTY. Serialized
@@ -35,9 +39,19 @@ pub enum SpawnSpec {
         jump_host: Option<String>,
         #[serde(rename = "extraArgs")]
         extra_args: Option<Vec<String>>,
+        /// SshHost.id (if any) — backend uses this to fetch a saved
+        /// password from keyring at spawn time. Never sent back to the
+        /// frontend.
+        #[serde(rename = "hostId")]
+        host_id: Option<String>,
     },
 }
 
+/// Type alias for the shared writer handle. Wrapped in Arc<Mutex<>> so the
+/// reader thread can also take it briefly to autotype a saved password at
+/// the SSH prompt.
+type SharedWriter = Arc<Mutex<Box<dyn Write + Send>>>;
+
 /// What we keep alive for each spawned PTY.
 ///
 /// `master` stays in scope to keep the PTY alive; we never write through it
@@ -46,7 +60,7 @@ pub enum SpawnSpec {
 struct PaneHandle {
     #[allow(dead_code)]
     master: Box<dyn MasterPty + Send>,
-    writer: Box<dyn Write + Send>,
+    writer: SharedWriter,
     #[allow(dead_code)]
     child: Box<dyn portable_pty::Child + Send + Sync>,
 }
@@ -84,6 +98,21 @@ impl PtyManager {
             })
             .context("openpty failed")?;
 
+        // Look up any saved password BEFORE building the command (cheap, no
+        // bytes-on-the-wire involved). If this is an SSH spawn with a host
+        // id and the user has stored a credential, the reader thread will
+        // autotype it when ssh prompts.
+        let saved_password = match &spec {
+            SpawnSpec::Ssh { host_id: Some(id), .. } => match creds::get(id) {
+                Ok(p) => p,
+                Err(e) => {
+                    tracing::warn!("keyring lookup for {id} failed: {e}");
+                    None
+                }
+            },
+            _ => None,
+        };
+
         let (cmd, spawn_err) = build_command(&spec)?;
         let child = pair.slave.spawn_command(cmd).context(spawn_err)?;
 
@@ -93,10 +122,11 @@ impl PtyManager {
             .master
             .try_clone_reader()
             .context("try_clone_reader failed")?;
-        let writer = pair
+        let writer_raw = pair
             .master
             .take_writer()
             .context("take_writer failed")?;
+        let writer: SharedWriter = Arc::new(Mutex::new(writer_raw));
 
         let id = self.next_id.fetch_add(1, Ordering::Relaxed);
 
@@ -104,16 +134,19 @@ impl PtyManager {
             id,
             PaneHandle {
                 master: pair.master,
-                writer,
+                writer: writer.clone(),
                 child,
             },
         );
 
-        // Reader thread: pump bytes -> base64 -> emit.
+        // Reader thread: pump bytes -> base64 -> emit. Also handles the
+        // password-prompt autotype state machine if `saved_password` is set.
         let app_for_reader = app.clone();
         let event_name = format!("pane://{id}/data");
+        let writer_for_reader = writer.clone();
         std::thread::spawn(move || {
             let mut buf = [0u8; 8192];
+            let mut pw_state = PasswordState::from(saved_password);
             loop {
                 match reader.read(&mut buf) {
                     Ok(0) => {
@@ -122,6 +155,10 @@ impl PtyManager {
                         break;
                     }
                     Ok(n) => {
+                        // Try to autotype before emitting so we don't wait
+                        // on the renderer; pw_state mutates here.
+                        pw_state.observe(&buf[..n], &writer_for_reader, id);
+
                         let chunk_b64 = B64.encode(&buf[..n]);
                         if let Err(e) =
                             app_for_reader.emit(&event_name, DataChunk { b64: chunk_b64 })
@@ -142,12 +179,16 @@ impl PtyManager {
     }
 
     pub fn write(&self, id: PaneId, bytes: &[u8]) -> Result<()> {
-        let mut panes = self.panes.lock();
-        let pane = panes
-            .get_mut(&id)
-            .ok_or_else(|| anyhow!("no pane with id {id}"))?;
-        pane.writer.write_all(bytes).context("pty write failed")?;
-        pane.writer.flush().ok();
+        let writer = {
+            let panes = self.panes.lock();
+            let pane = panes
+                .get(&id)
+                .ok_or_else(|| anyhow!("no pane with id {id}"))?;
+            pane.writer.clone()
+        };
+        let mut w = writer.lock();
+        w.write_all(bytes).context("pty write failed")?;
+        w.flush().ok();
         Ok(())
     }
 
@@ -279,6 +320,80 @@ fn build_command(spec: &SpawnSpec) -> Result<(CommandBuilder, &'static str)> {
     }
 }
 
+// ---- password-prompt autotype ----------------------------------------------
+
+/// How long after spawn we keep watching for a password prompt. If nothing
+/// matches in this window, we disarm and never autotype — so a remote shell
+/// that prints "password" hours later can't get our credential injected.
+const PASSWORD_AUTOTYPE_WINDOW: Duration = Duration::from_secs(30);
+/// Sliding window of recent PTY output we scan for the prompt. Keeps the
+/// scan bounded; matches don't need much context.
+const PROMPT_SCAN_TAIL: usize = 256;
+
+enum PasswordState {
+    Disabled,
+    Armed {
+        password: String,
+        deadline: Instant,
+        tail: Vec<u8>,
+    },
+}
+
+impl PasswordState {
+    fn from(password: Option<String>) -> Self {
+        match password {
+            None => Self::Disabled,
+            Some(p) => Self::Armed {
+                password: p,
+                deadline: Instant::now() + PASSWORD_AUTOTYPE_WINDOW,
+                tail: Vec::with_capacity(PROMPT_SCAN_TAIL * 2),
+            },
+        }
+    }
+
+    /// Called for each chunk of PTY output. Mutates state — once we write
+    /// the password (or time out) the state collapses to Disabled and this
+    /// becomes a no-op for the rest of the connection.
+    fn observe(&mut self, chunk: &[u8], writer: &SharedWriter, pane_id: PaneId) {
+        let (password, tail, deadline) = match self {
+            PasswordState::Disabled => return,
+            PasswordState::Armed { password, tail, deadline } => (password, tail, deadline),
+        };
+
+        if Instant::now() > *deadline {
+            *self = PasswordState::Disabled;
+            return;
+        }
+
+        tail.extend_from_slice(chunk);
+        if tail.len() > PROMPT_SCAN_TAIL {
+            let drop = tail.len() - PROMPT_SCAN_TAIL;
+            tail.drain(..drop);
+        }
+
+        if !looks_like_password_prompt(tail) {
+            return;
+        }
+
+        // Match — write the password + Enter, then collapse to Disabled.
+        let mut w = writer.lock();
+        if let Err(e) = w.write_all(password.as_bytes()) {
+            tracing::warn!("pane {pane_id}: password autotype write failed: {e}");
+        }
+        let _ = w.write_all(b"\n");
+        let _ = w.flush();
+        *self = PasswordState::Disabled;
+    }
+}
+
+fn looks_like_password_prompt(buf: &[u8]) -> bool {
+    // OpenSSH prompts: `<user>@<host>'s password:`, `Permission denied,
+    // please try again. password:`, `Enter passphrase for key '...':`.
+    // Lowercase the recent tail and substring-match — cheap and good enough.
+    let s = String::from_utf8_lossy(buf).to_ascii_lowercase();
+    s.contains("password:") || s.contains("passphrase")
+}
+
 // ---- distro enumeration -----------------------------------------------------
 
 /// Run a process without flashing a console window on Windows.