When using xhttp (UoT) mode on Android, the underlying TcpStream was
not protected with VpnService.protect(fd). This caused the TCP connection
to be routed back into the TUN interface, creating an infinite routing
loop and failing the connection immediately.
Added Android-specific socket protection to the TcpStream in connect_xhttp.
This fixes xhttp/UoT mode on mobile networks.
The core bug: server sent 5 TLS records in server_hello but client only
read the first one (ServerHello), then passed remaining bytes (CCS + fake
records) into RealityStream. RealityStream saw 0x14 (CCS) != 0x17 and
immediately returned an error, killing the connection.
Changes:
- reality.rs: append ChangeCipherSpec after ClientHello (RFC 8446 D.4)
export REALITY_SERVER_HANDSHAKE_RECORDS=5 constant
- xhttp.rs: drain all 5 server handshake records before creating RealityStream
- uot.rs: rebuild server_hello as proper 5-record TLS 1.3 flight:
ServerHello + CCS + fake EE (108B) + fake Cert (812B) + fake Fin (52B)
drain client CCS from raw stream before wrapping in RealityStream
- ostp-server/relay.rs: remove DNS port 53 interception — DNS queries
now pass through to the actual DNS server as regular TCP connections
- ostp-client/native_handler.rs (Windows): add explicit gateway/32 route
via real interface BEFORE setting default route via TUN to prevent loop
- ostp-client/native_handler.rs (Linux): properly detect real gateway and
add default route via TUN with metric 10 after server IP exclusion
- Remove redundant extra DNS host routes from Windows setup script
- Boxed HandshakeState in NoiseSession to reduce enum variant sizes
- Used is_ok() instead of let Ok(_) pattern
- Applied automatic clippy fixes for minor warnings
TUN Interface:
- Fixed adapter name to always be 'ostp_tun' by cleaning up stale
adapters before launch (prevents 'ostp_tun 2', 'ostp_tun 3', etc.)
- Parallelized route setup with tun2socks launch to save ~3 seconds
- Replaced fixed 2-second sleep with adapter readiness polling
- Added -NoProfile to all PowerShell calls for faster execution
Speed:
- Reduced handshake timeout from 10s to 5s
- Reduced tun2socks spawn buffer from 300ms to 0 (removed)
GUI:
- Added i18n support: English and Russian translations
- Language toggle button in header (EN/RU)
- Merged 'IP Ranges' field into 'Bypass IPs / CIDR Ranges'
- Removed separate IP ranges field
- All static text uses data-i18n attributes
- Status messages, labels, toasts all translated
- Replaced alert() calls with toast notifications
CI/CD:
- Added separate GUI build job for Windows x64 and arm64
- Produces ostp-windows-gui-{arch}.zip with: ostp-gui.exe + wintun.dll + tun2socks.exe
- Uses Tauri CLI v2 for build
Applied Kerckhoffs's principle: the protocol's security and obfuscation
now depend SOLELY on the access key. An adversary who reverse-engineers
the binary cannot build a DPI filter without knowing the key.
Changes:
- Replaced hardcoded salt string ('-ostp-psk-salt') with HKDF-SHA256.
The salt is now derived from the key hash itself — no protocol-specific
strings remain in the binary.
- Unified all secret derivation into derive_all_secrets() which produces
PSK, obfuscation key, and handshake padding range from a single HKDF
invocation.
- Handshake padding range is now key-derived: different access keys
produce different size distributions (min: 16-79, max: +48..+175).
A universal size-based filter is impossible without the key.
- HKDF-SHA256 (RFC 5869) implemented inline using existing hmac+sha2
dependencies — no new crate required.
What remains identifiable in the binary:
- 'Noise_NNpsk0_25519_ChaChaPoly_BLAKE2s' — standard Noise pattern
string, shared with many other projects, NOT OSTP-specific.
- Generic HMAC/SHA-256/ChaCha20-Poly1305 code — standard crypto
primitives used by millions of applications.
DPI/TSPU resistance:
- Handshake packets now padded with 32-128 random bytes (prevents size
fingerprinting — previously every handshake was exactly 52 bytes)
- Frame header reserved bytes randomized instead of always 0 (prevents
known-plaintext oracle inside encrypted payload)
- Padding jitter cap increased from 96 to 256 bytes for better traffic
pattern masking
GUI Windows app (tunnel/proxy not starting):
- CRITICAL: Added CREATE_NO_WINDOW flag to all reg.exe calls in sysproxy.rs.
In Tauri GUI context (no console window), Command::new('reg') was silently
failing because there was no attached console. This prevented the Windows
system proxy from being enabled.
- Added ProxyOverride bypass list (localhost;127.*;10.*;192.168.*;<local>)
to prevent proxy loop for local traffic
- Added comprehensive logging for all registry operations
- Set initial connection_state to 1 (connecting) instead of 0 — prevents
UI polling from immediately flipping back to 'disconnected' before the
handshake has a chance to begin
Code quality:
- Fixed log file paths: log_to_core_file() and log_to_file() now write next
to the executable instead of CWD. In GUI context, CWD could be
C:\Windows\System32, causing write failures or misplaced log files.
ostp-gui:
- GUI-01: Config parsing now strips JSONC comments via json_comments
crate, matching CLI behavior. Previously failed on any commented config.
- GUI-02: stop_tunnel now properly aborts the JoinHandle with a 2s
timeout instead of silently dropping it.
ostp-jni (Android SDK):
- JNI-01: Replaced all .unwrap() calls in JNI functions with safe
null_mut fallback. JNI functions must never panic.
- JNI-02: Added missing exclusions, multiplex, debug fields to
Kotlin SDK Config.toNativeJson(). Without these, serde deserialization
on the native side could fail or use wrong defaults.
- JNI-03: Replaced shutdown_background() with shutdown_timeout(3s)
to allow proper task cleanup and port unbinding.
- JNI-04: Updated Kotlin log string matchers to match professionalized
messages (Connection established, TUN tunnel established, etc.)
TUN handlers:
- TUN-01: Windows TUN cleanup guard now resets DNS via netsh. Previously
the custom DNS server remained configured after disconnect, causing
complete DNS resolution failure.
- Unified all remaining [ostp-client] log prefixes to [ostp] across
wintun_handler.rs, linux_handler.rs, and proxy.rs.
- Unified log prefix to [ostp] across all modules (was [OSTP Core],
[ostp-server], [ostp-client], [client], [bridge])
- Removed informal/casual phrasing from all user-visible messages
- Startup messages are clean and concise (mode, server, status)
- Error messages are actionable without being alarming
- Essential server logs (client connect/disconnect) always visible
- Essential client logs (connection status, errors) always visible
- TUN tunnel messages consistent across Windows and Linux
- Removed noisy eprintln from UDP reader hot path
- Status format: [ostp] Status: Connected (rtt=12.3ms)
Critical fixes (6):
- protocol.rs: in_flight_count() now counts only retransmittable Data frames,
not Ack/Nack control frames — eliminates false backpressure under load
- protocol.rs: NACK is now rate-limited to once per 30ms — prevents
retransmission storm during normal UDP jitter
- protocol.rs: zombie frames exceeding max_retries+4 are evicted each tick —
prevents unbounded memory growth and stale retransmits
- protocol.rs: Closing state now processes final in-flight packets instead
of silently dropping them — prevents data loss at session teardown
- server/lib.rs: stream_tx changed from bounded(10000) to unbounded_channel —
prevents TCP-reader collapse during Speedtest with 50+ streams
- bridge.rs: liveness timeout raised from 30s to 60s — prevents false
reconnect during heavy Speedtest load
Medium fixes (8):
- protocol.rs: ACK range truncation preserves cumulative range (index 0)
- bridge.rs: Ping now uses send_datagram() for correct TURN wrapping
- dispatcher.rs: replay_cache hard-capped at 100k entries (DoS protection)
- dispatcher.rs: old addr cleaned from addr_to_session on roaming
- server/lib.rs: TCP connect_target() now has 10s timeout
- config.rs: TURN section parsed during hot-reload
- proxy.rs: HTTP header parsing uses 512-byte chunks instead of 1-byte reads
- proxy.rs: stream_id wrap-around skips active IDs to prevent collision
- runner.rs: is_essential_log matches actual log strings from bridge.rs
Other:
- kex.rs: clearly marked as dead PQ stub (not used by protocol)
- README.md + README.ru.md: complete rewrite with architecture diagram
- docs/en/specification.md: updated ARQ section with all new semantics
ospab