Files
sanctum/src/mount.rs
T

990 lines
36 KiB
Rust

use std::convert::Infallible;
use std::net::SocketAddr;
use std::path::Path;
#[cfg(unix)]
use std::process::Command;
use std::sync::atomic::Ordering;
use std::time::{SystemTime, UNIX_EPOCH};
use anyhow::{bail, Context, Result};
use dav_server::{fakels::FakeLs, DavHandler};
use hyper::server::conn::http1;
use hyper::service::service_fn;
use hyper_util::rt::TokioIo;
use tokio::net::TcpListener;
use tokio::sync::watch;
use tracing::{debug, warn};
use zeroize::Zeroizing;
use crate::crypto::mnemonic_to_dek;
use crate::storage::Database;
use crate::ui;
use crate::vfs::SanctumFs;
/// Authentifizierungsmethode für das Einbinden eines Containers: Entweder Master-Passwort oder 24-Wort Notfallschlüssel.
#[derive(Debug, Clone)]
pub enum ContainerAuth {
Password(Zeroizing<String>),
RecoveryKey(Zeroizing<String>),
}
/// Hilfsfunktion zur Formatierung des Laufwerksbuchstabens (z. B. 'S' -> "S:")
pub fn format_drive(drive_letter: char) -> String {
format!("{}:", drive_letter.to_ascii_uppercase())
}
/// Trennt ein Windows-Netzlaufwerk via WNetCancelConnection2W bzw. Unix-Mountpoint via gio.
pub fn unmount_drive(drive_letter: char) -> Result<()> {
#[cfg(windows)]
{
crate::windows::unmount_drive_wnet(drive_letter)
}
#[cfg(unix)]
{
let _ = drive_letter;
Ok(())
}
#[cfg(not(any(windows, unix)))]
{
let _ = drive_letter;
Ok(())
}
}
/// Bindet ein Windows-Netzlaufwerk via in-process WNetAddConnection2W ein (R-05, kein Token in argv)
/// bzw. unter Unix via `gio mount dav://127.0.0.1:<PORT>/`.
fn run_mount_command(drive_letter: char, port: u16, session_token: &str) -> Result<()> {
#[cfg(windows)]
{
crate::windows::mount_drive_wnet(drive_letter, port, session_token)
}
#[cfg(unix)]
{
let dav_url = format!("dav://127.0.0.1:{}/", port);
let _ = Command::new("gio").args(["mount", &dav_url]).output();
let _ = (drive_letter, session_token);
Ok(())
}
#[cfg(not(any(windows, unix)))]
{
let _ = (drive_letter, port, session_token);
Ok(())
}
}
/// Startet den WebDAV-Server für den Sanctum-Container und bindet ihn als Netzlaufwerk (Windows) bzw. VFS (Linux) ein.
pub async fn mount_container(
container_path: &Path,
drive_letter: char,
mount_point: Option<&Path>,
requested_port: Option<u16>,
auth: ContainerAuth,
open_explorer: bool,
enable_tray: bool,
idle_timeout: Option<u64>,
lock_on_screen_lock: bool,
anti_leak: bool,
stealth: bool,
) -> Result<()> {
let drive_str = format_drive(drive_letter);
let _ = &drive_str;
let _ = mount_point;
let _ = open_explorer;
let _ = enable_tray;
let _ = lock_on_screen_lock;
if !container_path.exists() {
bail!(
"Containerdatei '{}' existiert nicht.",
container_path.display()
);
}
if !stealth {
println!();
ui::step(1, 4, "📦", "Öffne Container & verifiziere Header...");
}
let db = Database::open(container_path).context("Konnte Container-Datenbank nicht öffnen")?;
let meta = db
.read_meta()
.context("Konnte Container-Header nicht lesen")?;
let (dek, carrier_dek, carrier_node_id, version, vault_id) = match auth {
ContainerAuth::Password(ref password) => {
if !stealth {
ui::step(
2,
4,
"🔑",
"Leite KEK via Argon2id ab (konstante Zeit über alle Slots)...",
);
}
match meta.authenticate(password) {
Some(keys) => {
if !stealth {
ui::step(
3,
4,
"🔓",
"Master-Passwort erfolgreich verifiziert & DEK entschlüsselt!",
);
}
let vault_id = keys.slot_id();
let ver = keys.version();
let c_dek = keys.carrier_dek();
let c_nid = keys.carrier_node_id();
(keys.0, c_dek, c_nid, ver, vault_id)
}
None => {
bail!("Ungültiges Master-Passwort oder Container beschädigt");
}
}
}
ContainerAuth::RecoveryKey(ref phrase) => {
if !stealth {
ui::step(2, 4, "🔑", "Dekodiere DEK aus 24-Wort Notfallschlüssel...");
}
let dek = mnemonic_to_dek(phrase).context("Ungültiger 24-Wort Notfallschlüssel")?;
if !stealth {
ui::step(3, 4, "🔓", "Notfallschlüssel erfolgreich verifiziert!");
}
let carrier_node_id = db.find_carrier_node_id()?.unwrap_or(0);
let (carrier_dek, final_carrier_node_id, vault_id) = if carrier_node_id > 0 {
let slot_id = crate::recovery::detect_recovery_key_slot(&db, &dek, meta.version)?;
if slot_id == 1 {
if !stealth {
println!(" [i] Der angegebene Notfallschlüssel gehört zum Hidden-Vault (Slot 1).");
println!(" Für den Zugriff auf die Trägerdatei wird das Passwort des Standard-Vaults benötigt.");
}
let decoy_pass =
rpassword::prompt_password("Master-Passwort für Standard-Vault eingeben: ")
.context("Fehler beim Einlesen des Standard-Vault Passworts")?;
let decoy_keys = meta.authenticate(&decoy_pass).ok_or_else(|| {
anyhow::anyhow!("Ungültiges Passwort für Standard-Vault.")
})?;
(Some(decoy_keys.dek().clone()), Some(carrier_node_id), 1)
} else {
(None, Some(carrier_node_id), 0)
}
} else {
(None, None, 0)
};
(
dek,
carrier_dek,
final_carrier_node_id,
meta.version,
vault_id,
)
}
};
// S-06: Advisory Lock setzen, um parallele Mounts und schreibende Sync-Läufe abzuwehren
let _advisory_lock = db.acquire_advisory_lock_guard(false)?;
// 128-Bit Session-Token für Loopback-Schutz (CWE-306) & Anti-CSRF generieren
let mut token_bytes = [0u8; 16];
rand::RngCore::fill_bytes(&mut rand::rngs::OsRng, &mut token_bytes);
let session_token = hex::encode(token_bytes);
// WebDAV Filesystem und Handler konfigurieren (mit Anti-Leak Shield & Carrier-Routing)
let fs = SanctumFs::with_carrier(
db.clone(),
dek,
carrier_dek,
carrier_node_id,
version,
anti_leak,
vault_id,
);
let last_activity = fs.last_activity();
let dav_server = DavHandler::builder()
.filesystem(Box::new(fs))
.locksystem(FakeLs::new())
.build_handler();
// TCP-Port ermitteln und binden
let port_to_try = requested_port.unwrap_or(8443);
let listener = match TcpListener::bind(SocketAddr::from(([127, 0, 0, 1], port_to_try))).await {
Ok(l) => l,
Err(_) if requested_port.is_none() => {
TcpListener::bind(SocketAddr::from(([127, 0, 0, 1], 0)))
.await
.context("Konnte keinen lokalen TCP-Port binden")?
}
Err(e) => {
bail!("Konnte Port 127.0.0.1:{} nicht binden: {}", port_to_try, e);
}
};
let bound_addr = listener.local_addr()?;
let bound_port = bound_addr.port();
if !stealth {
#[cfg(windows)]
ui::step(
4,
4,
"🌐",
&format!(
"Starte WebDAV (Port {}) & binde Netzlaufwerk {} ein...",
bound_port, drive_str
),
);
#[cfg(not(windows))]
ui::step(
4,
4,
"🌐",
&format!(
"Starte WebDAV-Server auf Port {} & initialisiere VFS...",
bound_port
),
);
}
let (shutdown_tx, shutdown_rx) = watch::channel(false);
// Hyper HTTP Server Loop im Hintergrund starten
let server_handle = tokio::spawn(serve_webdav_loop(
listener,
dav_server,
session_token.clone(),
shutdown_rx,
));
// Netzlaufwerk bzw. Verzeichnis einbinden
if let Err(e) = run_mount_command(drive_letter, bound_port, &session_token) {
let _ = shutdown_tx.send(true);
let _ = server_handle.await;
return Err(e);
}
// Optional automatisch im Windows Explorer öffnen (visuelle Parität für Decoy und Hidden Vault)
#[cfg(windows)]
if open_explorer {
let _ = crate::windows::open_in_explorer(drive_letter);
}
// System-Tray Initialisierung (nur Windows)
#[cfg(windows)]
let (_tray_shutdown_tx, mut tray_shutdown_rx) = tokio::sync::mpsc::channel::<()>(1);
#[cfg(windows)]
let _tray = if enable_tray {
let icon_source = crate::windows::get_default_system_icon()
.unwrap_or(tray_item::IconSource::Resource(""));
let title = format!("Sanctum ({drive_str})");
match tray_item::TrayItem::new(&title, icon_source) {
Ok(mut tray) => {
let container_name = container_path
.file_name()
.unwrap_or_default()
.to_string_lossy()
.to_string();
let _ = tray.add_label(&format!("Sanctum: {drive_str} ({container_name})"));
let dl = drive_letter;
let _ = tray.add_menu_item("Im Explorer öffnen", move || {
let _ = crate::windows::open_in_explorer(dl);
});
let s_tx = _tray_shutdown_tx.clone();
let _ = tray.add_menu_item("Trennen & Beenden", move || {
let _ = s_tx.blocking_send(());
});
Some(tray)
}
Err(e) => {
debug!("System-Tray Icon konnte nicht erstellt werden: {e}");
None
}
}
} else {
None
};
// Inaktivitäts-Timer (Auto-Lock)
let (idle_shutdown_tx, mut idle_shutdown_rx) = tokio::sync::mpsc::channel::<()>(1);
if let Some(timeout_secs) = idle_timeout {
if timeout_secs > 0 {
let last_act = last_activity.clone();
let idle_tx = idle_shutdown_tx.clone();
tokio::spawn(async move {
let mut interval = tokio::time::interval(std::time::Duration::from_secs(1));
loop {
interval.tick().await;
let now = SystemTime::now()
.duration_since(UNIX_EPOCH)
.map(|d| d.as_secs())
.unwrap_or(0);
let last = last_act.load(Ordering::Relaxed);
if now.saturating_sub(last) >= timeout_secs {
let _ = idle_tx.send(()).await;
break;
}
}
});
}
}
// Windows-Sitzungssperre (Win + L Auto-Lock, nur Windows)
#[cfg(windows)]
let (session_lock_tx, mut session_lock_rx) = tokio::sync::mpsc::channel::<()>(1);
#[cfg(windows)]
let _session_monitor = if lock_on_screen_lock {
match crate::windows::start_session_lock_monitor(session_lock_tx) {
Ok(guard) => Some(guard),
Err(e) => {
warn!("Konnte Windows Session-Lock Monitor nicht aktivieren: {e}");
None
}
}
} else {
None
};
if stealth {
#[cfg(windows)]
println!("Sanctum: Netzlaufwerk {} bereit.", drive_str);
#[cfg(not(windows))]
println!("Sanctum: WebDAV-Server auf Port {} bereit.", bound_port);
} else {
println!();
println!("┌─────────────────────────────────────────────────────────────┐");
println!("│ ✔ Sanctum Container erfolgreich gemountet │");
println!("└─────────────────────────────────────────────────────────────┘");
println!();
println!(" • Container: {}", container_path.display());
#[cfg(windows)]
println!(
" • Netzlaufwerk: {} (im Windows Explorer bereit)",
ui::cyan(&drive_str)
);
#[cfg(not(windows))]
{
if let Some(mp) = mount_point {
println!(" • Mountpoint: {}", ui::cyan(&mp.display().to_string()));
} else {
println!(" • Modus: WebDAV Userland-VFS");
}
}
println!(
" • WebDAV-URL: http://127.0.0.1:{}/ (lokal geschützt)",
bound_port
);
#[cfg(not(windows))]
{
for line in format_linux_mount_instructions(bound_port, &session_token, mount_point) {
println!("{}", line);
}
}
if let Some(secs) = idle_timeout {
println!(" • Auto-Lock: Inaktivität nach {}s", secs);
}
#[cfg(windows)]
if lock_on_screen_lock {
println!(" • Sitzung: Automatisches Sperren bei Win + L aktiv");
}
if anti_leak {
#[cfg(windows)]
println!(" • Anti-Leak: Explorer-Metadatenfilter aktiv (Thumbs.db, desktop.ini blockiert)");
#[cfg(not(windows))]
println!(" • Anti-Leak: VFS-Metadatenfilter aktiv (.directory, .Trash, desktop.ini blockiert)");
}
#[cfg(windows)]
if enable_tray {
println!(" • System-Tray: Icon aktiv (Rechtsklick für Explorer/Trennen)");
}
println!();
#[cfg(windows)]
println!(
" [{}] Drücke [Ctrl+C] oder nutze das Tray-Icon zum Beenden.",
ui::yellow("Tipp")
);
#[cfg(not(windows))]
println!(
" [{}] Drücke [Ctrl+C] zum sicheren Beenden.",
ui::yellow("Tipp")
);
println!();
}
// Windows Console Close Monitor (CTRL_CLOSE_EVENT / CTRL_SHUTDOWN_EVENT, nur Windows)
#[cfg(windows)]
let (console_close_tx, mut console_close_rx) = tokio::sync::mpsc::channel::<()>(1);
#[cfg(windows)]
let _console_guard =
crate::windows::start_console_ctrl_monitor(console_close_tx, drive_letter).ok();
// Unix Signale (SIGTERM, SIGHUP)
#[cfg(unix)]
let mut sigterm =
tokio::signal::unix::signal(tokio::signal::unix::SignalKind::terminate()).ok();
#[cfg(unix)]
let mut sighup = tokio::signal::unix::signal(tokio::signal::unix::SignalKind::hangup()).ok();
// Warten auf Beendigungssignal (Ctrl+C, Tray-Klick, Inaktivität, Win+L, Konsolenfenster-Schließen)
#[cfg(windows)]
tokio::select! {
res = tokio::signal::ctrl_c() => {
let _ = res;
if !stealth {
println!();
println!(" {} Beendigungssignal (Ctrl+C) empfangen.", ui::yellow("[!]"));
}
}
Some(()) = console_close_rx.recv() => {
if !stealth {
println!();
println!(" {} Konsolenfenster wird geschlossen — sichere Trennung ausgeführt!", ui::yellow("[!]"));
}
}
Some(()) = tray_shutdown_rx.recv() => {
if !stealth {
println!();
println!(" {} Beendigungssignal aus System-Tray empfangen.", ui::yellow("[!]"));
}
}
Some(()) = session_lock_rx.recv() => {
if !stealth {
println!();
println!(" {} Windows-Sitzung gesperrt (Win + L) — Auto-Lock ausgelöst!", ui::yellow("[!]"));
}
}
Some(()) = idle_shutdown_rx.recv() => {
if !stealth {
println!();
println!(" {} Inaktivitäts-Timeout erreicht — Auto-Lock ausgelöst!", ui::yellow("[!]"));
}
}
}
#[cfg(unix)]
tokio::select! {
res = tokio::signal::ctrl_c() => {
let _ = res;
if !stealth {
println!();
println!(" {} Beendigungssignal (Ctrl+C) empfangen.", ui::yellow("[!]"));
}
}
_ = async {
match sigterm.as_mut() {
Some(s) => { s.recv().await; }
None => { std::future::pending::<()>().await; }
}
} => {
if !stealth {
println!();
println!(" {} Beendigungssignal (SIGTERM) empfangen.", ui::yellow("[!]"));
}
}
_ = async {
match sighup.as_mut() {
Some(s) => { s.recv().await; }
None => { std::future::pending::<()>().await; }
}
} => {
if !stealth {
println!();
println!(" {} Beendigungssignal (SIGHUP) empfangen.", ui::yellow("[!]"));
}
}
Some(()) = idle_shutdown_rx.recv() => {
if !stealth {
println!();
println!(" {} Inaktivitäts-Timeout erreicht — Auto-Lock ausgelöst!", ui::yellow("[!]"));
}
}
}
#[cfg(not(any(windows, unix)))]
tokio::select! {
res = tokio::signal::ctrl_c() => {
let _ = res;
if !stealth {
println!();
println!(" {} Beendigungssignal (Ctrl+C) empfangen.", ui::yellow("[!]"));
}
}
Some(()) = idle_shutdown_rx.recv() => {
if !stealth {
println!();
println!(" {} Inaktivitäts-Timeout erreicht — Auto-Lock ausgelöst!", ui::yellow("[!]"));
}
}
}
if stealth {
let _ = unmount_drive(drive_letter);
let _ = shutdown_tx.send(true);
let _ = server_handle.await;
if let Ok(freelist) = db.freelist_count() {
if freelist > 0 {
let _ = db.incremental_vacuum(None);
}
}
let _ = db.checkpoint();
#[cfg(windows)]
println!("Sanctum: Laufwerk {} getrennt und geschlossen.", drive_str);
#[cfg(not(windows))]
println!("Sanctum: Container geschlossen und WebDAV-Server beendet.");
} else {
#[cfg(windows)]
{
print!(
" {} Trenne Windows-Netzlaufwerk {} ... ",
ui::dim("[-]"),
drive_str
);
let _ = std::io::Write::flush(&mut std::io::stdout());
// Automatisches Unmount
if let Err(e) = unmount_drive(drive_letter) {
println!("{}", ui::yellow(&format!("Warnung ({e})")));
} else {
println!("{}", ui::green("OK"));
}
}
#[cfg(not(windows))]
{
print!(" {} Beende WebDAV-Server ... ", ui::dim("[-]"));
let _ = std::io::Write::flush(&mut std::io::stdout());
println!("{}", ui::green("OK"));
}
// HTTP Server beenden
let _ = shutdown_tx.send(true);
let _ = server_handle.await;
// Storage-Kompaktierung (Incremental Vacuum), falls freie Seiten existieren
if let Ok(freelist) = db.freelist_count() {
if freelist > 0 {
print!(
" {} Führe Storage-Kompaktierung aus ({} freie Seiten) ... ",
ui::dim("[-]"),
freelist
);
let _ = std::io::Write::flush(&mut std::io::stdout());
match db.incremental_vacuum(None) {
Ok(freed) => println!("{} ({} Seiten freigegeben)", ui::green("OK"), freed),
Err(e) => println!("{}", ui::yellow(&format!("Warnung ({e})"))),
}
}
}
// SQLite WAL Checkpoint erzwingen
print!(" {} Führe SQLite WAL-Checkpoint aus ... ", ui::dim("[-]"));
let _ = std::io::Write::flush(&mut std::io::stdout());
if let Err(e) = db.checkpoint() {
println!("{}", ui::red(&format!("Fehler ({e})")));
} else {
println!("{}", ui::green("OK"));
}
println!();
println!(
"{} Sanctum Container wurde sicher und vollständig geschlossen.",
ui::green("✔")
);
println!();
}
drop(db);
// S-10: Verifikation und Bereinigung von temporären SQLite WAL- und SHM-Dateien
let base_os = container_path.as_os_str().to_os_string();
let mut wal = base_os.clone();
wal.push("-wal");
let _ = std::fs::remove_file(wal);
let mut shm = base_os;
shm.push("-shm");
let _ = std::fs::remove_file(shm);
Ok(())
}
/// Überprüft, ob ein Host-Header exakt auf Loopback (127.0.0.1, localhost, [::1], ::1) zeigt (Anti-DNS-Rebinding & S-06).
/// Striktes Parsing von Host und Port ohne anfällige starts_with-Präfixprüfungen.
pub fn is_loopback_host(host_str: &str) -> bool {
let host_trimmed = host_str.trim().to_ascii_lowercase();
if host_trimmed.is_empty() {
return false;
}
if host_trimmed == "::1" {
return true;
}
let host_part = if host_trimmed.starts_with('[') {
// IPv6 bracketed: [::1] oder [::1]:port
if let Some(bracket_end) = host_trimmed.find(']') {
let inside = &host_trimmed[1..bracket_end];
let after = &host_trimmed[bracket_end + 1..];
if !after.is_empty() {
if !after.starts_with(':') {
return false;
}
if after[1..].parse::<u16>().is_err() {
return false;
}
}
inside
} else {
return false;
}
} else {
// IPv4 oder Hostname: localhost, localhost:8443, 127.0.0.1, 127.0.0.1:8443
if let Some((h, p)) = host_trimmed.rsplit_once(':') {
if p.parse::<u16>().is_ok() {
h
} else {
return false;
}
} else {
&host_trimmed
}
};
matches!(host_part, "127.0.0.1" | "localhost" | "::1")
}
/// Erzeugt die plattformspezifischen Linux-Mount-Anweisungen und Authentifizierungsdaten (M-03).
pub fn format_linux_mount_instructions(
port: u16,
token: &str,
mount_point: Option<&std::path::Path>,
) -> Vec<String> {
let mut lines = Vec::new();
lines.push(format!(
" • WebDAV-Auth: Benutzer: sanctum | Token: {}",
token
));
lines.push(format!(
" • gio Befehl: echo {} | gio mount dav://sanctum@127.0.0.1:{}/",
token, port
));
if let Some(mp) = mount_point {
lines.push(format!(
" • davfs2: mount -t davfs -o username=sanctum http://127.0.0.1:{}/ {}",
port,
mp.display()
));
} else {
lines.push(format!(
" • davfs2: mount -t davfs -o username=sanctum http://127.0.0.1:{}/ /mnt/sanctum",
port
));
}
lines
}
/// Maximale Anzahl gleichzeitiger Verbindungen zum lokalen WebDAV-Endpunkt (Schutz gegen Socket-Exhaustion).
const MAX_CONCURRENT_DAV_CONNECTIONS: usize = 64;
/// Timeout für das Lesen von HTTP-Headern (Schutz gegen Slowloris-Angriffe auf Loopback).
const HTTP_HEADER_READ_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(15);
/// Hilfsfunktion zur Validierung von HTTP Basic Auth.
/// Unterstützt Format `username:password` (wobei Passwort dem Session-Token entspricht).
/// SA-06: Verwendet strikten Constant-Time-Vergleich gegen Timing-Side-Channel-Angriffe.
pub fn check_basic_auth(auth_header: &str, expected_token: &str) -> bool {
let auth_str = auth_header.trim();
let encoded = if let Some(rest) = auth_str.strip_prefix("Basic ") {
rest
} else if let Some(rest) = auth_str.strip_prefix("basic ") {
rest
} else {
return false;
};
use base64::Engine;
let decoded_bytes = match base64::engine::general_purpose::STANDARD.decode(encoded.trim()) {
Ok(bytes) => bytes,
Err(_) => return false,
};
let decoded_str = match std::str::from_utf8(&decoded_bytes) {
Ok(s) => s,
Err(_) => return false,
};
use subtle::ConstantTimeEq;
if let Some((_user, pass)) = decoded_str.split_once(':') {
pass.as_bytes().ct_eq(expected_token.as_bytes()).into()
} else {
false
}
}
/// Hilfsfunktion zur Validierung des X-Sanctum-Token Headers.
/// SA-06: Verwendet strikten Constant-Time-Vergleich gegen Timing-Side-Channel-Angriffe.
pub fn check_token_header(headers: &hyper::HeaderMap, expected_token: &str) -> bool {
use subtle::ConstantTimeEq;
if let Some(val) = headers.get("X-Sanctum-Token") {
if let Ok(val_str) = val.to_str() {
return val_str
.trim()
.as_bytes()
.ct_eq(expected_token.as_bytes())
.into();
}
}
false
}
/// Prüft, ob eine URI oder deren Query-Parameter das sensible Session-Token enthält (SA-05 / CWE-598).
pub fn uri_contains_token(uri: &hyper::Uri, session_token: &str) -> bool {
if session_token.is_empty() {
return false;
}
uri.path().contains(session_token) || uri.query().unwrap_or("").contains(session_token)
}
/// Erzeugt eine standardkonforme HTTP 401 Unauthorized Antwort mit WWW-Authenticate Header.
fn unauthorized_response() -> hyper::Response<dav_server::body::Body> {
hyper::Response::builder()
.status(hyper::StatusCode::UNAUTHORIZED)
.header(hyper::header::WWW_AUTHENTICATE, "Basic realm=\"Sanctum\"")
.header(hyper::header::CONTENT_LENGTH, "0")
.body(dav_server::body::Body::empty())
.unwrap()
}
/// Führt die asynchrone WebDAV HTTP-Server-Schleife mit Header-basierter Authentifizierung & Host-Header Sicherheits-Middleware aus.
pub async fn serve_webdav_loop(
listener: TcpListener,
dav_server: DavHandler,
session_token: String,
mut shutdown_rx: watch::Receiver<bool>,
) {
let conn_semaphore =
std::sync::Arc::new(tokio::sync::Semaphore::new(MAX_CONCURRENT_DAV_CONNECTIONS));
loop {
tokio::select! {
res = listener.accept() => {
let (stream, _) = match res {
Ok(val) => val,
Err(e) => {
warn!("Verbindungsfehler im TCP-Listener: {e}");
continue;
}
};
// RT-01: Schutz gegen Connection-Starvation / Socket-Flooding (CWE-400)
let permit = match conn_semaphore.clone().try_acquire_owned() {
Ok(p) => p,
Err(_) => {
warn!(
"WebDAV-Verbindungslimit ({} aktive Verbindungen) erreicht: Wehre potenziellen Connection-Starvation-Angriff ab.",
MAX_CONCURRENT_DAV_CONNECTIONS
);
drop(stream);
continue;
}
};
let io = TokioIo::new(stream);
let handler = dav_server.clone();
let expected_token = session_token.clone();
tokio::spawn(async move {
let _permit = permit; // Permit wird bei Verbindungsende automatisch freigegeben
let service = service_fn(move |req| {
let h = handler.clone();
let token = expected_token.clone();
async move {
// 1. RT-02: Strikte Fail-Closed Host-Header Validierung (Anti-DNS-Rebinding & Anti-Spoofing)
let host_valid = match req.headers().get(hyper::header::HOST) {
Some(host_val) => match host_val.to_str() {
Ok(host_str) => is_loopback_host(host_str),
Err(_) => false,
},
None => false,
};
if !host_valid {
warn!(
"Abgewiesener Zugriff: Fehlender, ungültiger oder externer Host-Header ({:?})",
req.headers().get(hyper::header::HOST)
);
let res = hyper::Response::builder()
.status(hyper::StatusCode::FORBIDDEN)
.header(hyper::header::CONTENT_LENGTH, "0")
.body(dav_server::body::Body::empty())
.unwrap();
return Ok::<_, Infallible>(res);
}
// 2. SA-05: Verhindere Session-Token in Request-URI oder Query (CWE-598).
// Session-Tokens dürfen ausschließlich in HTTP-Headern übertragen werden.
if uri_contains_token(req.uri(), &token) {
warn!("Abgewiesener Zugriff: Session-Token in URI/Query übermittelt (SA-05 / CWE-598)");
let res = hyper::Response::builder()
.status(hyper::StatusCode::FORBIDDEN)
.header(hyper::header::CONTENT_LENGTH, "0")
.body(dav_server::body::Body::empty())
.unwrap();
return Ok::<_, Infallible>(res);
}
// 3. SA-05 & SA-06: Header-basierte Authentifizierung mit Constant-Time Token-Vergleich
// a) HTTP Basic Auth (Authorization: Basic ...)
// b) Header X-Sanctum-Token
let mut authenticated = false;
if let Some(auth_val) = req.headers().get(hyper::header::AUTHORIZATION) {
if let Ok(auth_str) = auth_val.to_str() {
if check_basic_auth(auth_str, &token) {
authenticated = true;
}
}
}
if !authenticated && check_token_header(req.headers(), &token) {
authenticated = true;
}
if !authenticated {
debug!("Abgewiesener unauthentifizierter Zugriff auf: {}", req.uri().path());
return Ok::<_, Infallible>(unauthorized_response());
}
Ok::<_, Infallible>(h.handle(req).await)
}
});
// RT-01: Header-Read-Timeout & TokioTimer zur aktiven Abwehr von Slowloris-Hanging-Sockets
let mut builder = http1::Builder::new();
builder.timer(hyper_util::rt::TokioTimer::new());
builder.header_read_timeout(HTTP_HEADER_READ_TIMEOUT);
if let Err(err) = builder.serve_connection(io, service).await {
debug!("HTTP-Verbindungsende: {:?}", err);
}
});
}
_ = shutdown_rx.changed() => {
debug!("WebDAV-Server-Task empfängt Shutdown-Signal.");
break;
}
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_is_loopback_host_validation() {
assert!(is_loopback_host("127.0.0.1"));
assert!(is_loopback_host("127.0.0.1:8443"));
assert!(is_loopback_host("localhost"));
assert!(is_loopback_host("localhost:8443"));
assert!(is_loopback_host("[::1]"));
assert!(is_loopback_host("[::1]:8443"));
// Abweisung externer Hosts oder DNS-Rebinding-Attacken
assert!(!is_loopback_host("evil.com"));
assert!(!is_loopback_host("attacker.local"));
assert!(!is_loopback_host("192.168.1.50"));
assert!(!is_loopback_host("10.0.0.1"));
assert!(!is_loopback_host(""));
}
#[test]
fn test_format_drive() {
assert_eq!(format_drive('s'), "S:");
assert_eq!(format_drive('Z'), "Z:");
}
#[test]
fn test_check_basic_auth() {
use base64::Engine;
let token = "deadbeefcafebabe0123456789abcdef";
let creds = format!("sanctum:{}", token);
let header_val = format!(
"Basic {}",
base64::engine::general_purpose::STANDARD.encode(creds)
);
assert!(check_basic_auth(&header_val, token));
// Kleingeschriebenes basic Präfix
let lower_header = format!(
"basic {}",
base64::engine::general_purpose::STANDARD.encode(format!("user:{}", token))
);
assert!(check_basic_auth(&lower_header, token));
// Falsches Token
let wrong_token_header = format!(
"Basic {}",
base64::engine::general_purpose::STANDARD.encode("sanctum:wrongtoken")
);
assert!(!check_basic_auth(&wrong_token_header, token));
// Ungültiges Base64 oder Format
assert!(!check_basic_auth("Basic !!!notbase64!!!", token));
assert!(!check_basic_auth("Bearer 12345", token));
assert!(!check_basic_auth("", token));
}
#[test]
fn test_check_token_header() {
let token = "deadbeefcafebabe0123456789abcdef";
let mut headers = hyper::HeaderMap::new();
assert!(!check_token_header(&headers, token));
headers.insert("X-Sanctum-Token", token.parse().unwrap());
assert!(check_token_header(&headers, token));
let mut wrong_headers = hyper::HeaderMap::new();
wrong_headers.insert("X-Sanctum-Token", "wrong".parse().unwrap());
assert!(!check_token_header(&wrong_headers, token));
}
#[test]
fn test_uri_contains_token_rejection() {
let token = "deadbeefcafebabe0123456789abcdef";
// Token im Pfad
let uri_path: hyper::Uri = format!("http://127.0.0.1:8443/{}/Photos/vacation.jpg", token)
.parse()
.unwrap();
assert!(uri_contains_token(&uri_path, token));
// Token im Query-String
let uri_query: hyper::Uri =
format!("http://127.0.0.1:8443/Photos/vacation.jpg?token={}", token)
.parse()
.unwrap();
assert!(uri_contains_token(&uri_query, token));
// Harmloser Pfad ohne Token
let uri_clean: hyper::Uri = "http://127.0.0.1:8443/Photos/vacation.jpg".parse().unwrap();
assert!(!uri_contains_token(&uri_clean, token));
// Leeres Token darf niemals matchen
assert!(!uri_contains_token(&uri_clean, ""));
}
#[test]
fn test_m03_format_linux_mount_instructions() {
let token = "fedcba9876543210fedcba9876543210";
let instructions = format_linux_mount_instructions(
8443,
token,
Some(std::path::Path::new("/mnt/secure")),
);
let all_text = instructions.join("\n");
assert!(all_text.contains("Benutzer: sanctum"));
assert!(all_text.contains(token));
assert!(all_text.contains("gio mount dav://sanctum@127.0.0.1:8443/"));
assert!(all_text.contains("mount -t davfs -o username=sanctum http://127.0.0.1:8443/ /mnt/secure"));
}
}