- Introduced `relay_dual_lock_race_harness_security_tests.rs` to validate user liveness during lock hold and release cycles.
- Added `relay_quota_extended_attack_surface_security_tests.rs` to cover various quota scenarios including positive, negative, edge cases, and adversarial conditions.
- Implemented `relay_quota_lock_eviction_lifecycle_tdd_tests.rs` to ensure proper eviction of stale entries and lifecycle management of quota locks.
- Created `relay_quota_lock_eviction_stress_security_tests.rs` to stress test the eviction mechanism under high churn conditions.
- Enhanced `relay_quota_lock_pressure_adversarial_tests.rs` to verify reclaiming of unreferenced entries after explicit eviction.
- Developed `relay_quota_retry_allocation_latency_security_tests.rs` to benchmark and validate latency and allocation behavior under contention.
This commit introduces a comprehensive set of improvements to enhance
the security, reliability, and configurability of the proxy server,
specifically targeting adversarial resilience and high-load concurrency.
Security & Cryptography:
- Zeroize MTProto cryptographic key material (`dec_key`, `enc_key`)
immediately after use to prevent memory leakage on early returns.
- Move TLS handshake replay tracking after full policy/ALPN validation
to prevent cache poisoning by unauthenticated probes.
- Add `proxy_protocol_trusted_cidrs` configuration to restrict PROXY
protocol headers to trusted networks, rejecting spoofed IPs.
Adversarial Resilience & DoS Mitigation:
- Implement "Tiny Frame Debt" tracking in the middle-relay to prevent
CPU exhaustion from malicious 0-byte or 1-byte frame floods.
- Add `mask_relay_max_bytes` to strictly bound unauthenticated fallback
connections, preventing the proxy from being abused as an open relay.
- Add a 5ms prefetch window (`mask_classifier_prefetch_timeout_ms`) to
correctly assemble and classify fragmented HTTP/1.1 and HTTP/2 probes
(e.g., `PRI * HTTP/2.0`) before routing them to masking heuristics.
- Prevent recursive masking loops (FD exhaustion) by verifying the mask
target is not the proxy's own listener via local interface enumeration.
Concurrency & Reliability:
- Eliminate executor waker storms during quota lock contention by replacing
the spin-waker task with inline `Sleep` and exponential backoff.
- Roll back user quota reservations (`rollback_me2c_quota_reservation`)
if a network write fails, preventing Head-of-Line (HoL) blocking from
permanently burning data quotas.
- Recover gracefully from idle-registry `Mutex` poisoning instead of
panicking, ensuring isolated thread failures do not break the proxy.
- Fix `auth_probe_scan_start_offset` modulo logic to ensure bounds safety.
Testing:
- Add extensive adversarial, timing, fuzzing, and invariant test suites
for both the client and handshake modules.
- Introduced `handshake_real_bug_stress_tests.rs` to validate TLS and MTProto handshake behaviors under various conditions, including ALPN rejection and session ID handling.
- Implemented tests to ensure replay cache integrity and proper handling of malicious input without panicking.
- Added `handshake_timing_manual_bench_tests.rs` for performance benchmarking of user authentication paths, comparing preferred user handling against full user scans in both MTProto and TLS contexts.
- Included timing-sensitive tests to measure the impact of SNI on handshake performance.
- Introduced client TLS record wrapping tests to ensure correct handling of empty and oversized payloads.
- Added integration tests for middle relay to validate quota saturation behavior under concurrent pressure.
- Implemented high-risk security tests covering various payload scenarios, including alignment checks and boundary conditions.
- Developed length cast hardening tests to verify proper handling of wire lengths and overflow conditions.
- Created quota overflow lock tests to ensure stable behavior under saturation and reclaim scenarios.
- Refactored existing middle relay security tests for improved clarity and consistency in lock handling.
- Enhanced linting rules in `src/proxy/mod.rs` to enforce stricter code quality checks in production.
- Updated hash functions in `src/proxy/middle_relay.rs` for better efficiency.
- Added new security tests in `src/proxy/tests/middle_relay_stub_completion_security_tests.rs` to validate desynchronization behavior.
- Removed ignored test stubs in `src/proxy/tests/middle_relay_security_tests.rs` to clean up the test suite.
- Improved error handling and code readability in various transport modules, including `src/transport/middle_proxy/config_updater.rs` and `src/transport/middle_proxy/pool.rs`.
- Introduced new padding functions in `src/stream/frame_stream_padding_security_tests.rs` to ensure consistent behavior across different implementations.
- Adjusted TLS stream validation in `src/stream/tls_stream.rs` for better boundary checking.
- General code cleanup and dead code elimination across multiple files to enhance maintainability.
- Bump versions of several dependencies in Cargo.toml for improved functionality and security, including:
- socket2 to 0.6
- nix to 0.31
- toml to 1.0
- x509-parser to 0.18
- dashmap to 6.1
- rand to 0.10
- reqwest to 0.13
- notify to 8.2
- ipnetwork to 0.21
- webpki-roots to 1.0
- criterion to 0.8
- Introduce `OnceLock` for secure random number generation in multiple modules to ensure thread safety and reduce overhead.
- Refactor random number generation calls to use the new `RngExt` trait methods for consistency and clarity.
- Add new PNG files for architectural documentation.
- Introduced regression tests for relay quota wake liveness to ensure proper handling of contention and wake events.
- Added adversarial tests to validate the behavior of the quota system under stress and contention scenarios.
- Implemented security tests for the TLS stream to verify the preservation of pending plaintext during state transitions.
- Enhanced the pool writer tests to ensure proper quarantine behavior and validate the removal of writers from the registry.
- Included fuzz testing to assess the robustness of the quota and TLS handling mechanisms against unexpected inputs and states.
- Introduced `relay_quota_boundary_blackhat_tests.rs` to validate behavior under quota limits, including edge cases and adversarial conditions.
- Added `relay_quota_model_adversarial_tests.rs` to ensure quota management maintains integrity during bidirectional communication and various load scenarios.
- Created `relay_quota_overflow_regression_tests.rs` to address overflow issues and ensure that quota limits are respected during aggressive data transmission.
- Implemented `route_mode_coherence_adversarial_tests.rs` to verify the consistency of route mode transitions and timestamp management across different relay modes.
- Renamed test functions in `client_tls_clienthello_truncation_adversarial_tests.rs` to remove "but_leaks" suffix for clarity.
- Added new tests in `direct_relay_business_logic_tests.rs` to validate business logic for data center resolution and scope hints.
- Introduced tests in `direct_relay_common_mistakes_tests.rs` to cover common mistakes in direct relay configurations.
- Added security tests in `direct_relay_security_tests.rs` to ensure proper handling of symlink and parent swap scenarios.
- Created `direct_relay_subtle_adversarial_tests.rs` to stress test concurrent logging and validate scope hint behavior.
- Implemented `relay_quota_lock_pressure_adversarial_tests.rs` to test quota lock behavior under high contention and stress.
- Updated `relay_security_tests.rs` to include quota lock contention tests ensuring proper behavior under concurrent access.
- Introduced `ip_tracker_hotpath_adversarial_tests.rs` to validate the performance and correctness of the IP tracking logic under various scenarios.
- Implemented tests for masking shape classifier resistance against threshold attacks, ensuring that blurring reduces accuracy and increases overlap between classes.
- Added tests for masking shape guard functionality, verifying that it maintains expected behavior under various conditions, including timeout paths and clean EOF scenarios.
- Introduced helper functions for calculating accuracy and handling timing samples to support the new tests.
- Ensured that the masking shape hardening configuration is properly utilized in tests to validate its effectiveness.
- Introduced red-team expected-fail tests for client masking shape hardening.
- Added integration tests for masking AB envelope blur to improve obfuscation.
- Implemented masking security tests to validate the behavior of masking under various conditions.
- Created tests for masking shape above-cap blur to ensure proper functionality.
- Developed adversarial tests for masking shape hardening to evaluate robustness against attacks.
- Added timing normalization security tests to assess the effectiveness of timing obfuscation.
- Implemented red-team expected-fail tests for timing side-channel vulnerabilities.
- Removed assertions for expected client hello messages in multiple TLS fallback tests to streamline the test logic.
- Updated the tests to focus on verifying the trailing TLS records received after the fallback.
- Enhanced the masking functionality by adding shape hardening features, including dynamic padding based on sent data size.
- Modified the relay_to_mask function to accommodate new parameters for shape hardening.
- Updated masking security tests to reflect changes in the relay_to_mask function signature.
- Rename MAX_TLS_RECORD_SIZE to MAX_TLS_PLAINTEXT_SIZE for clarity.
- Rename MAX_TLS_CHUNK_SIZE to MAX_TLS_CIPHERTEXT_SIZE to reflect its purpose.
- Deprecate old constants in favor of new ones.
- Update various parts of the codebase to use the new constants, including validation checks and tests.
- Add new tests to ensure compliance with RFC 8446 regarding TLS record sizes.
- Refactor existing tests to improve clarity and specificity in naming.
- Introduce new tests for minimum and maximum TLS ClientHello sizes, ensuring proper masking behavior for malformed probes.
- Implement differential timing tests to compare latency between malformed TLS and plain web requests, ensuring similar performance characteristics.
- Add adversarial tests for truncated TLS ClientHello probes, verifying that even malformed traffic is masked as legitimate responses.
- Enhance the overall test suite for robustness against probing attacks, focusing on edge cases and potential vulnerabilities in TLS handling.
- Introduced multiple adversarial tests for MTProto handshake to ensure robustness against replay attacks, invalid mutations, and concurrent flooding.
- Implemented a function to build proxy headers based on the specified version, improving the handling of masking protocols.
- Added tests to validate the behavior of the masking functionality under various conditions, including unknown proxy protocol versions and oversized payloads.
- Enhanced relay tests to ensure stability and performance under high load and half-close scenarios.
This commit introduces the `into_inner_with_pending_plaintext` method to the `FakeTlsReader` struct. This method allows users to extract the underlying reader along with any pending plaintext data that may have been buffered during the TLS reading process. The method handles the state transition and ensures that any buffered data is returned as a vector, facilitating easier management of plaintext data in TLS streams.
Исправлена критическая логическая ошибка в цепочке Fake TLS -> MTProto.
Ранее при валидном TLS-хендшейке, но неверном MTProto-пакете, прокси
ошибочно передавал в маскирующий релей обернутый (FakeTls) поток.
Теперь транспорт корректно разворачивается (unwrap) до сырого сокета
через .into_inner(), обеспечивая полную прозрачность (wire-transparency)
для DPI и маскирующего бэкенда.
Security & Hardening:
- Логика приведена в соответствие с требованиями OWASP ASVS L2 (V5: Validation, Sanitization and Encoding).
- Реализовано поведение "fail-closed": при любой ошибке верификации прокси мимикрирует под обычный веб-сервер, не раскрывая своей роли.
- Улучшена диагностика и логирование состояний аутентификации для защиты от активного пробинга.
Adversarial Testing (Black-hat mindset):
- Добавлен отдельный пакет `client_tls_mtproto_fallback_security_tests.rs` (18+ тестов).
- Покрыты сценарии: хаос-фрагментация (побайтовая нарезка TLS-записей), record-splitting,
half-close состояния, сбросы бэкенда и replay-pressure.
- В `client_adversarial_tests.rs` добавлено 10+ тестов на "злые" гонки (race conditions),
утечки лимитов по IP и проверку изоляции состояний параллельных сессий.
- Все 832 теста проходят (passed) в locked-режиме.
- Introduced a new test module for middle relay idle policy security tests, covering various scenarios including soft mark, hard close, and grace periods.
- Implemented functions to create crypto readers and encrypt data for testing.
- Enhanced the Stats struct to include counters for relay idle soft marks, hard closes, pressure evictions, and protocol desync closes.
- Added corresponding increment and retrieval methods for the new stats fields.
Alexey